WO2022085870A1 - Device and method for providing forest fire risk index - Google Patents

Device and method for providing forest fire risk index Download PDF

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WO2022085870A1
WO2022085870A1 PCT/KR2021/000833 KR2021000833W WO2022085870A1 WO 2022085870 A1 WO2022085870 A1 WO 2022085870A1 KR 2021000833 W KR2021000833 W KR 2021000833W WO 2022085870 A1 WO2022085870 A1 WO 2022085870A1
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index
soil moisture
ffmc
forest fire
data
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PCT/KR2021/000833
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French (fr)
Korean (ko)
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권춘근
이병두
김성용
임정호
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대한민국(산림청 국립산림과학원장)
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Publication of WO2022085870A1 publication Critical patent/WO2022085870A1/en

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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00Fire alarms; Alarms responsive to explosion
    • G08B17/005Fire alarms; Alarms responsive to explosion for forest fires, e.g. detecting fires spread over a large or outdoors area
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/24Earth materials
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/24Earth materials
    • G01N33/246Earth materials for water content
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01WMETEOROLOGY
    • G01W1/00Meteorology
    • G01W1/02Instruments for indicating weather conditions by measuring two or more variables, e.g. humidity, pressure, temperature, cloud cover or wind speed
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01WMETEOROLOGY
    • G01W1/00Meteorology
    • G01W1/10Devices for predicting weather conditions
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01WMETEOROLOGY
    • G01W1/00Meteorology
    • G01W1/14Rainfall or precipitation gauges
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06NCOMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS
    • G06N20/00Machine learning
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06QINFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q50/00Information and communication technology [ICT] specially adapted for implementation of business processes of specific business sectors, e.g. utilities or tourism
    • G06Q50/10Services
    • G06Q50/26Government or public services
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00Fire alarms; Alarms responsive to explosion
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B31/00Predictive alarm systems characterised by extrapolation or other computation using updated historic data

Definitions

  • the present invention relates to an apparatus and method for providing a forest fire risk index, and more particularly, an apparatus for generating a forest fire risk index model optimized for the Korean peninsula, and predicting a forest fire risk index for a forecast date using the generated forest fire risk index model and methods.
  • This study is related to the establishment of an integrated forest fire risk forecasting system (No. 1405004074) using meteorological big data conducted under the supervision of the National Institute of Forest Science with the funds of the Korea Forest Service for 2018-2020.
  • An object of the present invention is to provide an apparatus and method for providing a forest fire risk index for generating a forest fire risk index model optimized for the Korean Peninsula, and predicting a forest fire risk index for a forecast date using the generated forest fire risk index model. there is.
  • the device for providing a forest fire risk index obtains a forest fire risk index using a forest fire frequent area map, a modified Fine Fuel Moisture Code (FFMC), a drought index, and a monthly weight.
  • Forest Fire Risk Index Acquisition Department and, based on the forest fire risk index obtained through the forest fire risk index acquisition unit, a forecasting unit for obtaining a forest fire risk index value for a forecast date; includes, wherein the monthly weight is obtained based on all wildfires that have occurred in the past Using the ratio of the number of forest fires per month, the greater the number of forest fires per month, the greater the weight.
  • the forest fire risk index acquisition unit may obtain the forest fire risk index through the formula (the wildfire frequent area map + 0.5) * (the modified FFMC) * (1.5 - the drought index) * (the monthly weight). there is.
  • the modified FFMC is, in the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content of the day calculated using relative humidity, precipitation measured at noon, temperature, and wind speed, FFMC initial value , the coefficient of the equation for calculating the precipitation reference value, the FFMC reference value, and the drying rate is corrected, the coefficient of the equation for calculating the moisture content of the previous day is corrected, the coefficient of the equation for calculating the FFMC value using the minimum moisture content is corrected, and at noon
  • the accumulated precipitation per day is used instead of the measured precipitation, and the precipitation reference value may be larger than that of the conventional FFMC.
  • a drought index obtaining unit for obtaining the drought index by using the soil moisture index downscaled to a grid size of 1 km, a Normalized Different Water Index (NDWI), and a Temperature Condition Index (TCI); may further include.
  • the drought index obtaining unit may obtain the drought index through the formula 0.4 * (the downscaled soil moisture index) + 0.3 * (the NDWI) + 0.3 * (the TCI).
  • a soil moisture index downscaling model is created, It may further include; a soil moisture index acquisition unit for obtaining the downscaled soil moisture index by inputting the input variable converted to the grid size into the soil moisture index downscaling model.
  • the soil moisture index acquisition unit using the data upscaled to a grid size of 25 km as training data, the TRMM precipitation data, the ASCAT soil moisture data, the NDVI, the LST, and the DEM as input variables, Using the GLDAS soil moisture data as an output variable, a first soil moisture index downscaling model is created, and the TRMM precipitation data, the NDVI, the LST and A second soil moisture index downscaling model is generated using the DEM as an input variable and the GLDAS soil moisture data as an output variable, and the input variable converted to a grid size of 1 km is used as the first soil moisture index downscaling model to obtain a first soil moisture index downscaled to a grid size of 1 km by inputting into A second soil moisture index may be obtained, and the part missing from the first soil moisture index may be replaced with the second soil moisture index to obtain the downscaled soil moisture index.
  • a method for providing a forest fire risk index according to a preferred embodiment of the present invention for achieving the above object is a method for providing a forest fire risk index performed by a device for providing a forest fire risk index, a forest fire frequent area map, a modified FFMC (Fine Fuel Moisture) Code), obtaining a forest fire risk index using the drought index and monthly weight; and, based on the wildfire risk index, obtaining a forest fire risk index value for a forecast date, wherein the monthly weight is based on all forest fires that have occurred in the past. The higher the number of forest fires per month, the greater the weight.
  • FFMC Fast Fuel Moisture
  • the forest fire risk index acquisition step is to obtain the forest fire risk index through the formula (the wildfire frequent area map + 0.5) * (the modified FFMC) * (1.5 - the drought index) * (the monthly weight) can be made of
  • the modified FFMC is, in the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content of the day calculated using relative humidity, precipitation measured at noon, temperature, and wind speed, FFMC initial value , the coefficient of the equation for calculating the precipitation reference value, the FFMC reference value, and the drying rate is corrected, the coefficient of the equation for calculating the moisture content of the previous day is corrected, the coefficient of the equation for calculating the FFMC value using the minimum moisture content is corrected, and at noon
  • the accumulated precipitation per day is used instead of the measured precipitation, and the precipitation reference value may be larger than that of the conventional FFMC.
  • the method may further include; obtaining the drought index using a soil moisture index downscaled to a grid size of 1 km, a Normalized Different Water Index (NDWI), and a Temperature Condition Index (TCI).
  • NDWI Normalized Different Water Index
  • TCI Temperature Condition Index
  • a soil moisture index downscaling model is created, The method may further include inputting the input variable converted into a grid size into the soil moisture index downscaling model to obtain the downscaled soil moisture index.
  • the computer program according to a preferred embodiment of the present invention for achieving the above technical problem is stored in a computer-readable recording medium and executes any one of the methods for providing the forest fire risk index described above on the computer.
  • the apparatus and method for providing a forest fire risk index by generating a forest fire risk index model optimized for the Korean Peninsula, and predicting the forest fire risk index for the forecast date using the generated forest fire risk index model, Damage can be minimized through efficient on-site forest fire preparation (forward deployment of firefighting resources, etc.)
  • FIG. 1 is a block diagram illustrating an apparatus for providing a forest fire risk index according to a preferred embodiment of the present invention.
  • FIG. 2 is a view for explaining a soil moisture index downscaling model according to a preferred embodiment of the present invention.
  • FIG. 3 is a view for explaining the results of the soil moisture index downscaling model according to a preferred embodiment of the present invention.
  • FIG. 4 is a view for explaining the results of the soil moisture index downscaling model excluding the ASCAT soil moisture data according to a preferred embodiment of the present invention.
  • FIG. 5 is a view for explaining the final downscaled soil moisture index according to a preferred embodiment of the present invention.
  • the left side of FIG. 5 shows the results of the first soil moisture index downscaling model, and the right side of FIG. 5 shows the first It shows that the missing part in the result of the soil moisture index downscaling model is replaced with the result of the second soil moisture index downscaling model.
  • FIG. 6 is a view for explaining a drought factor according to a preferred embodiment of the present invention.
  • FIG. 7 is a diagram for explaining a result of a drought index model to which weights are applied according to a preferred embodiment of the present invention.
  • FIG. 8 is a view for explaining a map of a forest fire frequent area according to a preferred embodiment of the present invention.
  • FIG. 9 is a view for explaining the reason for using the FFMC as a factor of the forest fire risk index according to a preferred embodiment of the present invention. (b) compares FFMC with the number of wildfires by 10 days in 2015.
  • FIG. 10 is a view for explaining a result of comparing the spatial distribution of a modified FFMC according to a preferred embodiment of the present invention and a conventional FFMC.
  • 11 is a view for explaining a result of comparing the number of forest fires per month between the modified FFMC and the conventional FFMC according to a preferred embodiment of the present invention.
  • FIG. 12 is a view for explaining a drought index used to obtain a forest fire risk index according to a preferred embodiment of the present invention.
  • FIG. 13 is a view for explaining a first monthly weight used to obtain a forest fire risk index according to a preferred embodiment of the present invention.
  • FIG. 14 is a diagram for explaining a second monthly weight used to obtain a forest fire risk index according to a preferred embodiment of the present invention.
  • 15 is a flowchart for explaining a method for providing a forest fire risk index according to a preferred embodiment of the present invention.
  • first and second are for distinguishing one component from other components, and the scope of rights should not be limited by these terms.
  • a first component may be termed a second component, and similarly, a second component may also be termed a first component.
  • identification symbols eg, a, b, c, etc.
  • each step is clearly Unless a specific order is specified, the order may differ from the specified order. That is, each step may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.
  • ' ⁇ unit' as used herein means software or a hardware component such as a field-programmable gate array (FPGA) or ASIC, and ' ⁇ unit' performs certain roles.
  • '-part' is not limited to software or hardware.
  • ' ⁇ ' may be configured to reside on an addressable storage medium or may be configured to refresh one or more processors.
  • ' ⁇ ' indicates components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data structures and variables.
  • the functions provided in the components and ' ⁇ units' may be combined into a smaller number of components and ' ⁇ units' or further separated into additional components and ' ⁇ units'.
  • FIG. 1 is a block diagram illustrating an apparatus for providing a forest fire risk index according to a preferred embodiment of the present invention.
  • the apparatus 100 for providing a forest fire risk index generates a forest fire risk index model optimized for the Korean Peninsula, and uses the generated forest fire risk index model to predict forest fire risk for a forecast date. predict the index.
  • the forest fire risk index providing apparatus 100 may include a soil moisture index obtaining unit 110 , a drought index obtaining unit 130 , a forest fire risk index obtaining unit 150 , and a forecasting unit 170 .
  • the soil moisture index acquisition unit 110 is based on a machine learning algorithm, TRMM (Tropical Rainfall Measuring Mission) precipitation data, ASCAT (Advanced SCATterometter) soil moisture data, NDVI (Normalized Difference Vegetation Index), LST (Land Surface Temperature) and A soil moisture index downscaling model is generated using a digital elevation model (DEM) as an input variable and global land data assimilation system (GLDAS) soil moisture data as an output variable.
  • TRMM Temporal Rainfall Measuring Mission
  • ASCAT Advanced SCATterometter
  • NDVI Normalized Difference Vegetation Index
  • LST Land Surface Temperature
  • a soil moisture index downscaling model is generated using a digital elevation model (DEM) as an input variable and global land data assimilation system (GLDAS) soil moisture data as an output variable.
  • DEM digital elevation model
  • GDAS global land data assimilation system
  • the machine learning algorithm may use one of a random forest (RF), support vector regression (SVR), and an artificial neural network (ANN).
  • RF random forest
  • SVR support vector regression
  • ANN artificial neural network
  • the present invention can generate a soil moisture index downscaling model using a random forest (RF).
  • the soil moisture index acquisition unit 110 uses, as training data, the upscaled data to a grid size of 25 km, which is the same as the grid size of the GLDAS soil moisture data, as training data for the unity of spatial resolution between the data. create
  • the soil moisture index acquisition unit 110 obtains the soil moisture index downscaled to the grid size of 1 km by inputting the input variable converted to the 1km grid size to the soil moisture index downscaling model.
  • the soil moisture index acquisition unit 110 uses the data upscaled to a grid size of 25 km as training data, and uses TRMM precipitation data, ASCAT soil moisture data, NDVI, LST and DEM as input variables, Using the GLDAS soil moisture data as an output variable, a first soil moisture index downscaling model may be generated.
  • the soil moisture index acquisition unit 110 uses the upscaled data to a grid size of 25 km as training data, TRMM precipitation data, NDVI, LST, and DEM as input variables, and GLDAS soil moisture data as output variables. , it is possible to generate a second soil moisture index downscaling model. That is, the soil moisture index acquisition unit 110 may generate the second soil moisture index downscaling model by using the remaining input variables except for the ASCAT soil moisture data among the input variables of the first soil moisture index downscaling model.
  • the soil moisture index acquisition unit 110 inputs the input variable converted to a grid size of 1 km into the first soil moisture index downscaling model to obtain a first soil moisture index downscaled to a grid size of 1 km,
  • the input variable converted to a grid size of 1 km is input to the second soil moisture index downscaling model to obtain a second soil moisture index downscaled to a grid size of 1 km, and the missing part in the first soil moisture index is the second
  • the final soil moisture index downscaled to a grid size of 1 km can be obtained.
  • the drought index acquisition unit 130 uses the soil moisture index downscaled to a grid size of 1 km obtained through the soil moisture index acquisition unit 110, NDWI (Normalized Different Water Index), and TCI (Temperature Condition Index) during drought get an index
  • the drought index obtaining unit 130 may obtain the drought index through the following equation.
  • Drought Index 0.4 * (Downscaled Soil Moisture Index) + 0.3 * (NDWI) + 0.3 * (TCI)
  • the drought index acquisition unit 130 may acquire the drought index by using the downscaled soil moisture index, NDWI, and TCI, which are factors showing a high correlation with drought among the following drought-related factors.
  • TRMM Tropical Rainfall Measuring Mission 1 (accumulated precipitation per week) / TRMM 2 (accumulated precipitation in 2 weeks)
  • the drought index acquisition unit 130 may obtain three drought indices through the following three equations, and obtain an average value of the obtained three drought indices as the final drought index.
  • Drought index 0.4 * (downscaled soil moisture index) + 0.2 * (NDWI) + 0.4 * (TRMM)
  • Drought index 0.3 * (downscaled soil moisture index) + 0.2 * (NDWI) + 0.3 * (TRMM) + 0.1 * (TCI)
  • the drought index obtaining unit 130 may generate a drought index model using the One-Class SVM, and may obtain the drought index using the generated drought index model, but the drought index obtaining unit 130 according to the present invention ) obtains the drought index through the above equation.
  • the drought index acquisition unit 130 obtains the first drought index through Equation 1 above using the downscaled soil moisture index, NDWI, and TCI, and uses the One-Class SVM to generate the drought index model.
  • a second drought index may be obtained through the process, and an average value of the obtained first and second drought indexes may be obtained as a final drought index.
  • the drought index acquisition unit 130 may use the average value of the three drought indices obtained through Equations 1 to 3 above as the first drought index.
  • the forest fire risk index acquisition unit 150 obtains a forest fire risk index using the drought index and monthly weights obtained through the forest fire frequent area map, the modified Fine Fuel Moisture Code (FFMC), and the drought index acquisition unit 130 .
  • FFMC Fine Fuel Moisture Code
  • the monthly weight may be given a greater weight as the number of monthly forest fires increases, using the ratio of the number of monthly wildfires obtained based on all forest fires that have occurred in the past.
  • the monthly weight is the first monthly weight that gives a greater weight as the number of monthly wildfires increases according to the ratio of the number of monthly wildfires based on all forest fires that have occurred in the past It may be a second monthly weight that weights only a specific month (March- May) with the highest number of cases.
  • the present invention can obtain a forest fire risk index by using the first monthly weight.
  • the modified FFMC is the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content of the day calculated using the relative humidity, precipitation measured at noon, temperature, and wind speed.
  • FFMC the coefficient of the formula for calculating the FFMC initial value, the precipitation reference value, the FFMC reference value and the drying rate is modified in the conventional FFMC, the coefficient of the formula calculating the moisture content of the previous day is modified, and the minimum moisture content is used
  • the forest fire risk index acquisition unit 150 may acquire the forest fire risk index through the following equation.
  • Wildfire Risk Index (Wildfire Hotspot Map + 0.5) * (Adjusted FFMC) * (1.5 - Drought Index) * (Monthly Weighted)
  • the forest fire risk index acquisition unit 150 obtains the first forest fire risk index through the above formula using the “first monthly weight” as the monthly weight, and uses the “second monthly weight” as the monthly weight to obtain the above
  • the second wildfire risk index is obtained through the ceremony, and the average value of the obtained first wildfire risk index and the second wildfire risk index may be obtained as the final forest fire risk index.
  • the forecasting unit 170 acquires a forest fire risk index value for the forecast date based on the forest fire risk index obtained through the forest fire risk index obtaining unit 150 .
  • GLDAS Global Land Data Assimilation System
  • ASCAT Advanced SCATterometter
  • NDVI Normalized Difference Vegetation Index
  • GLDAS used as soil moisture data is a data assimilation data system based on three surface models of Mosaic, Arthur, and Community Land Model.
  • Arthur model was used among the three surface models.
  • the Arthur model provided the moisture data of the 1 cm ⁇ 10 cm soil layer with a spatial resolution of 25 km 4 times a day (03, 09, 15, and 12:00), and the corresponding soil moisture data (m 3 /m 3 ) was averaged daily and used.
  • MOD13A2 which is 16-day synthetic NDVI data with 1 km spatial resolution calculated from MODIS (Moderate Resolution Imaging Spectroradiometer) of Terra satellite
  • MOD11A2 output which is 8-day synthetic LST data with 1 km spatial resolution
  • the DEM used the global DEM data of the Shuttle Radar Topography Mission (SRTM) with a spatial resolution of 90 m.
  • TRMM 3B42 daily data with a spatial resolution of 25 km were accumulated over a period of 5 and 7 days, respectively.
  • the soil moisture field observation data (%) provided by the Agricultural Promotion Agency was used to validate the model after unit conversion to m 3 /m 3 . All data except field observation data were used after masking in the range of the study area.
  • FIG. 2 is a view for explaining a soil moisture index downscaling model according to a preferred embodiment of the present invention.
  • a downscaling model for soil moisture detailing was developed using various machine learning and artificial intelligence techniques.
  • three techniques were used, respectively: random forest (RF), support vector regression analysis (SVR), and artificial neural network (ANN).
  • the downscaling model was developed for each technique by setting the GLDAS soil moisture data as the dependent variable and setting a total of five data except the soil moisture field observation data as independent variables. For the unity of spatial resolution between data, all input data were applied to model building after upscaling to a spatial resolution of 25 km, the same grid size as GLDAS. After that, the 5 input data converted to the 1km grid size is applied to the developed model to finally obtain the downscaling soil moisture result of the 1km grid.
  • the model was constructed by dividing the training data and the validation data by dividing the data from 2013 to 2014 at a ratio of 8:2, and additionally 10-fold cross-validation was performed with data for the same period.
  • the soil moisture downscaling result produced through each model was verified by comparing it with the field observation soil moisture data of the Agricultural Promotion Administration.
  • FIG. 3 is a view for explaining the results of the soil moisture index downscaling model according to a preferred embodiment of the present invention.
  • Figure 4 is a view for explaining the results of the soil moisture index downscaling model excluding the ASCAT soil moisture data according to a preferred embodiment of the present invention
  • Figure 5 is the final downscaled soil moisture index according to a preferred embodiment of the present invention
  • the left side of FIG. 5 shows the results of the first soil moisture index downscaling model
  • the right side of FIG. 5 shows the missing part from the results of the first soil moisture index downscaling model with the second soil moisture index It represents substitution with the result of the downscaling model.
  • the main factors that cause wildfires in Korea include misfires of mountain climbers and cigarette butts, and the occurrence of wildfires due to drought is extremely rare. However, if a forest fire occurs during a drought, the damage (area) may be increased. Therefore, in the present invention, the correlation between drought and forest fires was analyzed using data on actual wildfire occurrence of 1 ha or more from 2013 to 2018. Later, satellite data available in real time were used to develop the forest fire risk index.
  • the drought-related factors used include the above-mentioned soil moisture downscaling data, NDDI (Normalized Different Drought Index), NDWI (Normalized Different Water Index) 5, 6, 7 (Divided into 5, 6, 7 depending on the use of SWIR band) , NMDI (Normalized Multi-band Drought Index), TCI (Temperature Condition Index), VCI (Vegetation Condition Index), TRMM 1 and 2 (accumulated precipitation for one and two weeks) data.
  • NDDI Normalized Different Drought Index
  • NDWI Normalized Different Water Index
  • TCI Tempo Condition Index
  • VCI Vegetation Condition Index
  • TRMM 1 and 2 accumulated precipitation for one and two weeks
  • NDDI (NDVI - NDWI) / (NDVI + NDWI)
  • NDWI (band2 - SWIR) / (band2 + SWIR)
  • NMDI (band2 - (band6 - band7)) / (band2 + (band6-band7))
  • FIG. 6 is a view for explaining a drought factor according to a preferred embodiment of the present invention.
  • a drought index model was developed by applying a weight to the drought factor selected through correlation analysis and by applying One-Class SVM, one of the types of machine learning. Indices were developed using soil moisture, NDWI, TCI, NMDI, and TRMM, which showed a high correlation.
  • 7 is a diagram for explaining a result of a drought index model to which weights are applied according to a preferred embodiment of the present invention.
  • 7 shows the results of each scheme for actual wildfire occurrence, Schemes 4 and 5 including precipitation factors showed a severe drought state compared to other schemes, and showed a drought state irrespective of the area damaged by the forest fire. However, even in areas where wildfires did not occur, drought conditions were indicated.
  • TCI has a relatively large correlation compared to NMDI
  • Scheme 2 without precipitation factors and Scheme 4 and 5 with precipitation factors were used for forest fire risk index development.
  • One-Class SVM uses a hyperplane to classify one class and outliers in the same way as the existing binary classification and multi-classification SVMs. Based on the margin support vectors, internal vectors are assigned a class, and external vectors are identified as outliers.
  • FIG. 8 is a view for explaining a map of a forest fire frequent area according to a preferred embodiment of the present invention.
  • the map of areas prone to forest fires is a numerical map of location information for all wildfires (10,560 cases) that occurred from 1991 to 2015. Based on this location information, density analysis is performed to identify areas of concern where wildfires may occur frequently. This is the selected map.
  • the average distance method and nearest neighbor analysis were performed to estimate the average distance between forest fires, and the density function first suggested by Kernel was used to finally select the area with a high incidence of forest fires.
  • FIG. 9 is a view for explaining the reason for using the FFMC as a factor of the forest fire risk index according to a preferred embodiment of the present invention. (b) compares FFMC with the number of wildfires by 10 days in 2015.
  • the Canada Fire Weather Index is calculated using weather information such as temperature, relative humidity, wind speed, and precipitation.
  • ISI Initial Spread Index
  • BUI Building Up Index
  • FFMC predicts the moisture content of the fine fuel in the forest above ground
  • DMC predicts the humidity of the surface fuel layer in the forest
  • DC predicts the likelihood of seasonal drought and geological formation by predicting the moisture of deep organic matter layers and coarse fuel in the ground
  • ISI is calculated by combining FFMC and wind speed factors.
  • FFMC predicts the moisture content of fine fuel using temperature, relative humidity, wind speed, and precipitation information, and the range is 0 to 99. A higher number means a higher probability of ignition.
  • FFMC has a higher correlation than CFWI, which is the final index, and as a result of predicting the probability of forest fire with a regression analysis model using FFMC, it has a statistical significance of 5% ( Park Heung-seok et al., 2009).
  • DWI Dynamic Weather Index
  • FFMC was more suitable for Korea than CFWI, and FFMC was used in the present invention. decided to do
  • FIG. 10 is a view for explaining the result of comparing the spatial distribution of the modified FFMC according to the preferred embodiment of the present invention and the conventional FFMC
  • FIG. 11 is the modified FFMC according to the preferred embodiment of the present invention and the conventional FFMC It is a diagram to explain the result of comparing with the number of forest fires per month.
  • FFMC is more suitable for Korea than CFWI, so that FFMC is used in the present invention.
  • FFMC was developed in the 1970s and has been continuously updated since then, and in order to create a more accurate forest fire risk index model, the process of optimizing the existing FFMC for the Korean environment was carried out.
  • FFMC calculates the equilibrium moisture content, drying rate, and minimum moisture content of the day using relative humidity, precipitation, temperature, and wind speed data, and finally calculates the FFMC. Accordingly, in the present invention, FFMC was optimized by modifying some coefficients according to the Korean environment.
  • the formula coefficients for calculating the FFMC initial value, the precipitation standard value, the FFMC standard value, and the drying rate were modified, and the coefficients of the formula for calculating the moisture content of the previous day and the formula for calculating the FFMC using the minimum amount were modified.
  • the coefficients were modified within the range of each coefficient, and the optimal coefficients were found by comparing with the number and area of wildfires in Korea.
  • the existing FFMC used precipitation measured at noon, but in the present invention, daily accumulated precipitation was used to make a daily FFMC.
  • the precipitation reference value was increased by changing the precipitation data from instantaneous precipitation to cumulative precipitation.
  • the FFMC 10 is a result of comparing the spatial distribution of the existing FFMC and the optimized FFMC (that is, the modified FFMC according to the present invention), and since precipitation determines the degree of drying and is an important variable in FFMC calculation, the FFMC most simulates the pattern of precipitation. I could see that a lot was followed.
  • the FFMC was modified to suit the Korean environment, and the existing FFMC, which was heavily biased in the amount of precipitation, was modified to affect it more gently.
  • CDF Cumulative Distribution Function
  • wildfire area > 50ha ⁇ 50 ha ⁇ 10ha ⁇ 1 ha existing FFMC FFMC average 87.0244 86.0494 83.8506 80.9751 CDF average 0.769 0.791 0.575 0.429 optimized FFMC FFMC average 60.9135 58.9741 51.8598 49.2367 CDF average 0.972 0.978 0.960 0.924
  • the average CDF value of the optimized FFMC was higher than 0.9, and the larger the damage area, the higher the average CDF value.
  • the FFMC modified for the Korean environment, was fused with the map of areas prone to forest fires and the drought index to develop a Fire Risk Index (FRI) suitable for the Korean environment.
  • the existing Canadian Forest Fire Hazard Index (CFWI) calculation method is generated by multiplying a function for wind and FFMC, a function for DMC and DC, and a coefficient as follows.
  • CFWI coefficient * f(wind,FFMC) * f(DMC,DC)
  • the forest fire risk index (FRI) was developed using the revised FFMC (revised FFMC), drought idx, and forest fire frequent area map (frequency) as coefficients as follows, and considering the seasonal characteristics A process for giving a different weight (temporal weight) for each month has been added.
  • FRI (frequency + 0.5) * (revised FFMC) * (1.5 - drought idx) * (temporal weight)
  • the constant added to the forest fire frequency and drought idx is to prevent the situation in which FRI becomes 0 when multiplied when each indices has a minimum value of 0.
  • FIG. 12 is a view for explaining a drought index used to obtain a forest fire risk index according to a preferred embodiment of the present invention.
  • the method of giving the monthly weight is the method of giving weight so that the larger the number of monthly occurrences, the greater the FRI value (FRI_M1) and the monthly forest fire Two methods were tested (FRI_M2), in which only March to May with the highest number of occurrences were weighted.
  • FRI_M1 and FRI_M2 were multiplied by monthly weights to consider seasonal characteristics.
  • CDF analysis was performed similarly to comparing the existing FFMC and the modified FFMC. A probability that is less than or equal to a certain value.
  • the FFMC and FRI of all wildfire pixels and non-wildfire pixels were calculated for the days of wildfires from 2014 to 2017, and then the CDF values of the wildfire pixels were averaged and derived as shown in [Table 3] below.
  • FIGS. 13 and 14 show the forest fire risk index (DWI) provided by the existing forest fire risk forecasting system of the Forestry Academy of the Korea Forest Service.
  • DWI forest fire risk index
  • 15 is a flowchart for explaining a method for providing a forest fire risk index according to a preferred embodiment of the present invention.
  • the apparatus 100 for providing a forest fire risk index may obtain a soil moisture index downscaled to a grid size of 1 km based on a machine learning algorithm ( S110 ).
  • the forest fire risk index providing device 100 is based on a machine learning algorithm, with TRMM precipitation data, ASCAT soil moisture data, NDVI, LST, and DEM as input variables, and soil moisture with GLDAS soil moisture data as output variables.
  • the machine learning algorithm may use one of random forest (RF), support vector regression (SVR), and artificial neural network (ANN).
  • RF random forest
  • SVR support vector regression
  • ANN artificial neural network
  • the present invention can generate a soil moisture index downscaling model using a random forest (RF).
  • the forest fire risk index providing device 100 uses, as training data, the upscaling data to a grid size of 25 km, which is the same as the grid size of the GLDAS soil moisture data, as training data for the unity of spatial resolution between the data, and the soil moisture index downscaling model create Then, the forest fire risk index providing apparatus 100 obtains a soil moisture index downscaled to a grid size of 1 km by inputting an input variable converted to a grid size of 1 km into a soil moisture index downscaling model.
  • the forest fire risk index providing device 100 uses the data upscaled to a grid size of 25 km as training data, TRMM precipitation data, ASCAT soil moisture data, NDVI, LST and DEM as input variables, Using the GLDAS soil moisture data as an output variable, a first soil moisture index downscaling model may be generated. And, the forest fire risk index providing device 100 uses the data upscaled to a grid size of 25 km as training data, TRMM precipitation data, NDVI, LST, and DEM as input variables, and GLDAS soil moisture data as output variables. , it is possible to generate a second soil moisture index downscaling model.
  • the forest fire risk index providing device 100 inputs the input variable converted to the grid size of 1 km into the first soil moisture index downscaling model to obtain the first soil moisture index downscaled to the grid size of 1 km,
  • the input variable converted to a grid size of 1 km is input to the second soil moisture index downscaling model to obtain a second soil moisture index downscaled to a grid size of 1 km, and the missing part in the first soil moisture index is the second
  • the final soil moisture index downscaled to a grid size of 1 km can be obtained.
  • the forest fire risk index providing apparatus 100 may obtain a drought index by using the soil moisture index, NDWI, and TCI downscaled to a grid size of 1 km (S130).
  • the forest fire risk index providing apparatus 100 may obtain the drought index through the equation 0.4 * (downscaled soil moisture index) + 0.3 * (NDWI) + 0.3 * (TCI).
  • the apparatus 100 for providing the forest fire risk index may obtain a forest fire risk index by using the wildfire frequent area map, the modified FFMC, the drought index, and the monthly weight (S150).
  • the apparatus 100 for providing the forest fire risk index may obtain the forest fire risk index through the equation (wildfire frequent area map + 0.5) * (modified FFMC) * (1.5 - drought index) * (monthly weight).
  • the monthly weight may be given a greater weight as the number of monthly forest fires increases, using the ratio of the number of monthly wildfires obtained based on all forest fires that have occurred in the past.
  • the modified FFMC is the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content of the day calculated using the relative humidity, precipitation measured at noon, temperature, and wind speed.
  • FFMC the coefficient of the formula for calculating the FFMC initial value, the precipitation reference value, the FFMC reference value and the drying rate is modified in the conventional FFMC, the coefficient of the formula calculating the moisture content of the previous day is modified, and the minimum moisture content is used
  • the forest fire risk index providing apparatus 100 obtains a forest fire risk index value for the forecast date based on the acquired wildfire risk index (S170).
  • the present invention is not necessarily limited to this embodiment. That is, within the scope of the object of the present invention, all the components may operate by selectively combining one or more.
  • all of the components may be implemented as one independent hardware, but a part or all of each component is selectively combined to perform some or all of the functions combined in one or a plurality of hardware program modules It may be implemented as a computer program having
  • such a computer program is stored in a computer readable media such as a USB memory, a CD disk, a flash memory, etc., read and executed by a computer, thereby implementing the embodiment of the present invention.
  • the recording medium of the computer program may include a magnetic recording medium, an optical recording medium, and the like.

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Abstract

A device and a method for providing a forest fire risk index, according to a preferred embodiment of the present invention, generate a forest fire risk index model optimized for the Korean Peninsula, and forecast a forest fire risk index for a forecast date by using the generated forest fire risk index model, and thus minimize damage through efficient on-site forest fire preparations (forward deployment of fire-extinguishing resources, and the like) and, further, can reduce the frequency of forest fires by providing necessary information for forest fire prevention.

Description

산불 위험 지수 제공 장치 및 방법Device and method for providing wildfire risk index
본 발명은 산불 위험 지수 제공 장치 및 방법에 관한 것으로서, 더욱 상세하게는 한반도에 최적화된 산불 위험 지수 모델을 생성하고, 생성된 산불 위험 지수 모델을 이용하여 예보일에 대한 산불 위험 지수를 예보하는 장치 및 방법에 관한 것이다. 본 연구는 2018~2020년도 산림청의 재원으로 국립산림과학원 주관으로 수행된 기상 빅데이터를 활용한 산불위험 통합예보 체계 구축(No. 1405004074)과 관련된다.The present invention relates to an apparatus and method for providing a forest fire risk index, and more particularly, an apparatus for generating a forest fire risk index model optimized for the Korean peninsula, and predicting a forest fire risk index for a forecast date using the generated forest fire risk index model and methods. This study is related to the establishment of an integrated forest fire risk forecasting system (No. 1405004074) using meteorological big data conducted under the supervision of the National Institute of Forest Science with the funds of the Korea Forest Service for 2018-2020.
기후 변화로 인한 한반도 내의 건조 일수가 증가함에 따라 연중 산불 발생 기간이 길어지는 등 산불 위험이 고조되고 있어 산불 위험 예측 정보를 사전에 제공할 필요성이 대두되고 있다.As the number of dry days in the Korean Peninsula increases due to climate change, the risk of forest fires is increasing, such as a longer period of wildfires throughout the year.
본 발명이 이루고자 하는 목적은, 한반도에 최적화된 산불 위험 지수 모델을 생성하고, 생성된 산불 위험 지수 모델을 이용하여 예보일에 대한 산불 위험 지수를 예보하는 산불 위험 지수 제공 장치 및 방법을 제공하는 데 있다.An object of the present invention is to provide an apparatus and method for providing a forest fire risk index for generating a forest fire risk index model optimized for the Korean Peninsula, and predicting a forest fire risk index for a forecast date using the generated forest fire risk index model. there is.
본 발명의 명시되지 않은 또 다른 목적들은 하기의 상세한 설명 및 그 효과로부터 용이하게 추론할 수 있는 범위 내에서 추가적으로 고려될 수 있다.Other objects not specified in the present invention may be additionally considered within the scope that can be easily inferred from the following detailed description and effects thereof.
상기의 목적을 달성하기 위한 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 장치는, 산불 다발 지역 지도, 수정된 FFMC(Fine Fuel Moisture Code), 가뭄 지수 및 월별 가중치를 이용하여 산불 위험 지수를 획득하는 산불 위험 지수 획득부; 및 상기 산불 위험 지수 획득부를 통해 획득한 상기 산불 위험 지수를 기반으로, 예보일에 대한 산불 위험 지수 값을 획득하는 예보부;를 포함하며, 상기 월별 가중치는, 과거에 발생한 모든 산불을 기반으로 획득한 월별 산불 발생 건수 비율을 이용하여, 월별 산불 발생 건수가 많을수록 더 큰 가중치가 부여된다.The device for providing a forest fire risk index according to a preferred embodiment of the present invention for achieving the above object obtains a forest fire risk index using a forest fire frequent area map, a modified Fine Fuel Moisture Code (FFMC), a drought index, and a monthly weight. Forest Fire Risk Index Acquisition Department; And, based on the forest fire risk index obtained through the forest fire risk index acquisition unit, a forecasting unit for obtaining a forest fire risk index value for a forecast date; includes, wherein the monthly weight is obtained based on all wildfires that have occurred in the past Using the ratio of the number of forest fires per month, the greater the number of forest fires per month, the greater the weight.
여기서, 상기 산불 위험 지수 획득부는, 식 (상기 산불 다발 지역 지도 + 0.5) * (상기 수정된 FFMC) * (1.5 - 상기 가뭄 지수) * (상기 월별 가중치)를 통해 상기 산불 위험 지수를 획득할 수 있다.Here, the forest fire risk index acquisition unit may obtain the forest fire risk index through the formula (the wildfire frequent area map + 0.5) * (the modified FFMC) * (1.5 - the drought index) * (the monthly weight). there is.
여기서, 상기 수정된 FFMC는, 상대 습도, 정오에 측정한 강수량, 온도, 풍속을 이용하여 계산된 당일의 평형 수분량, 건조율 및 최소 수분량을 기반으로 FFMC를 산출하는 종래의 FFMC에서, FFMC 초기값, 강수량 기준값, FFMC 기준값 및 건조율을 계산하는 식의 계수가 수정되고, 전날 수분량을 계산하는 식의 계수가 수정되며, 최소 수분량을 이용하여 FFMC 값을 계산하는 식의 계수가 수정되고, 정오에 측정한 강수량이 아닌 하루 누적 강수량이 이용되며, 강수량 기준값이 종래의 FFMC보다 커질 수 있다.Here, the modified FFMC is, in the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content of the day calculated using relative humidity, precipitation measured at noon, temperature, and wind speed, FFMC initial value , the coefficient of the equation for calculating the precipitation reference value, the FFMC reference value, and the drying rate is corrected, the coefficient of the equation for calculating the moisture content of the previous day is corrected, the coefficient of the equation for calculating the FFMC value using the minimum moisture content is corrected, and at noon The accumulated precipitation per day is used instead of the measured precipitation, and the precipitation reference value may be larger than that of the conventional FFMC.
여기서, 1km의 격자 크기로 다운스케일링된 토양 수분 지수, NDWI(Normalized Different Water Index) 및 TCI(Temperature Condition Index)를 이용하여 상기 가뭄 지수를 획득하는 가뭄 지수 획득부;를 더 포함할 수 있다.Here, a drought index obtaining unit for obtaining the drought index by using the soil moisture index downscaled to a grid size of 1 km, a Normalized Different Water Index (NDWI), and a Temperature Condition Index (TCI); may further include.
여기서, 상기 가뭄 지수 획득부는, 식 0.4 * (상기 다운스케일링된 토양 수분 지수) + 0.3 * (상기 NDWI) + 0.3 * (상기 TCI)을 통해 상기 가뭄 지수를 획득할 수 있다.Here, the drought index obtaining unit may obtain the drought index through the formula 0.4 * (the downscaled soil moisture index) + 0.3 * (the NDWI) + 0.3 * (the TCI).
여기서, 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, 기계 학습 알고리즘을 기반으로, TRMM(Tropical Rainfall Measuring Mission) 강수 자료, ASCAT(Advanced SCATterometter) 토양 수분 자료, NDVI(Normalised Difference Vegetation Index), LST(Land Surface Temperature) 및 DEM(digital Elevation Model)을 입력 변수로 하고, GLDAS(Global Land Data Assimilation System) 토양 수분 자료를 출력 변수로 하는, 토양 수분 지수 다운스케일링 모델을 생성하고, 1km의 격자 크기로 변환된 상기 입력 변수를 상기 토양 수분 지수 다운스케일링 모델에 입력하여 상기 다운스케일링된 토양 수분 지수를 획득하는 토양 수분 지수 획득부;를 더 포함할 수 있다.Here, using data upscaled to a grid size of 25 km as training data, based on a machine learning algorithm, TRMM (Tropical Rainfall Measuring Mission) precipitation data, ASCAT (Advanced SCATterometter) soil moisture data, NDVI (Normalized Difference Vegetation Index) ), Land Surface Temperature (LST), and Digital Elevation Model (DEM) as input variables, and Global Land Data Assimilation System (GLDAS) soil moisture data as output variables, a soil moisture index downscaling model is created, It may further include; a soil moisture index acquisition unit for obtaining the downscaled soil moisture index by inputting the input variable converted to the grid size into the soil moisture index downscaling model.
여기서, 상기 토양 수분 지수 획득부는, 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, 상기 TRMM 강수 자료, 상기 ASCAT 토양 수분 자료, 상기 NDVI, 상기 LST 및 상기 DEM을 입력 변수로 하고, 상기 GLDAS 토양 수분 자료를 출력 변수로 하는, 제1 토양 수분 지수 다운스케일링 모델을 생성하고, 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, 상기 TRMM 강수 자료, 상기 NDVI, 상기 LST 및 상기 DEM을 입력 변수로 하고, 상기 GLDAS 토양 수분 자료를 출력 변수로 하는, 제2 토양 수분 지수 다운스케일링 모델을 생성하며, 1km의 격자 크기로 변환된 입력 변수를 상기 제1 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 제1 토양 수분 지수를 획득하고, 1km의 격자 크기로 변환된 입력 변수를 상기 제2 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 제2 토양 수분 지수를 획득하며, 제1 토양 수분 지수에서 누락된 부분은 상기 제2 토양 수분 지수로 대체하여 상기 다운스케일링된 토양 수분 지수를 획득할 수 있다.Here, the soil moisture index acquisition unit, using the data upscaled to a grid size of 25 km as training data, the TRMM precipitation data, the ASCAT soil moisture data, the NDVI, the LST, and the DEM as input variables, Using the GLDAS soil moisture data as an output variable, a first soil moisture index downscaling model is created, and the TRMM precipitation data, the NDVI, the LST and A second soil moisture index downscaling model is generated using the DEM as an input variable and the GLDAS soil moisture data as an output variable, and the input variable converted to a grid size of 1 km is used as the first soil moisture index downscaling model to obtain a first soil moisture index downscaled to a grid size of 1 km by inputting into A second soil moisture index may be obtained, and the part missing from the first soil moisture index may be replaced with the second soil moisture index to obtain the downscaled soil moisture index.
상기의 목적을 달성하기 위한 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 방법은, 산불 위험 지수 제공 장치에 의해 수행되는 산불 위험 지수 제공 방법으로서, 산불 다발 지역 지도, 수정된 FFMC(Fine Fuel Moisture Code), 가뭄 지수 및 월별 가중치를 이용하여 산불 위험 지수를 획득하는 단계; 및 상기 산불 위험 지수를 기반으로, 예보일에 대한 산불 위험 지수 값을 획득하는 단계;를 포함하며, 상기 월별 가중치는, 과거에 발생한 모든 산불을 기반으로 획득한 월별 산불 발생 건수 비율을 이용하여, 월별 산불 발생 건수가 많을수록 더 큰 가중치가 부여된다.A method for providing a forest fire risk index according to a preferred embodiment of the present invention for achieving the above object is a method for providing a forest fire risk index performed by a device for providing a forest fire risk index, a forest fire frequent area map, a modified FFMC (Fine Fuel Moisture) Code), obtaining a forest fire risk index using the drought index and monthly weight; and, based on the wildfire risk index, obtaining a forest fire risk index value for a forecast date, wherein the monthly weight is based on all forest fires that have occurred in the past. The higher the number of forest fires per month, the greater the weight.
여기서, 상기 산불 위험 지수 획득 단계는, 식 (상기 산불 다발 지역 지도 + 0.5) * (상기 수정된 FFMC) * (1.5 - 상기 가뭄 지수) * (상기 월별 가중치)를 통해 상기 산불 위험 지수를 획득하는 것으로 이루어질 수 있다.Here, the forest fire risk index acquisition step is to obtain the forest fire risk index through the formula (the wildfire frequent area map + 0.5) * (the modified FFMC) * (1.5 - the drought index) * (the monthly weight) can be made of
여기서, 상기 수정된 FFMC는, 상대 습도, 정오에 측정한 강수량, 온도, 풍속을 이용하여 계산된 당일의 평형 수분량, 건조율 및 최소 수분량을 기반으로 FFMC를 산출하는 종래의 FFMC에서, FFMC 초기값, 강수량 기준값, FFMC 기준값 및 건조율을 계산하는 식의 계수가 수정되고, 전날 수분량을 계산하는 식의 계수가 수정되며, 최소 수분량을 이용하여 FFMC 값을 계산하는 식의 계수가 수정되고, 정오에 측정한 강수량이 아닌 하루 누적 강수량이 이용되며, 강수량 기준값이 종래의 FFMC보다 커질 수 있다.Here, the modified FFMC is, in the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content of the day calculated using relative humidity, precipitation measured at noon, temperature, and wind speed, FFMC initial value , the coefficient of the equation for calculating the precipitation reference value, the FFMC reference value, and the drying rate is corrected, the coefficient of the equation for calculating the moisture content of the previous day is corrected, the coefficient of the equation for calculating the FFMC value using the minimum moisture content is corrected, and at noon The accumulated precipitation per day is used instead of the measured precipitation, and the precipitation reference value may be larger than that of the conventional FFMC.
여기서, 1km의 격자 크기로 다운스케일링된 토양 수분 지수, NDWI(Normalized Different Water Index) 및 TCI(Temperature Condition Index)를 이용하여 상기 가뭄 지수를 획득하는 단계;를 더 포함할 수 있다.Here, the method may further include; obtaining the drought index using a soil moisture index downscaled to a grid size of 1 km, a Normalized Different Water Index (NDWI), and a Temperature Condition Index (TCI).
여기서, 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, 기계 학습 알고리즘을 기반으로, TRMM(Tropical Rainfall Measuring Mission) 강수 자료, ASCAT(Advanced SCATterometter) 토양 수분 자료, NDVI(Normalised Difference Vegetation Index), LST(Land Surface Temperature) 및 DEM(digital Elevation Model)을 입력 변수로 하고, GLDAS(Global Land Data Assimilation System) 토양 수분 자료를 출력 변수로 하는, 토양 수분 지수 다운스케일링 모델을 생성하고, 1km의 격자 크기로 변환된 상기 입력 변수를 상기 토양 수분 지수 다운스케일링 모델에 입력하여 상기 다운스케일링된 토양 수분 지수를 획득하는 단계;를 더 포함할 수 있다.Here, using data upscaled to a grid size of 25 km as training data, based on a machine learning algorithm, TRMM (Tropical Rainfall Measuring Mission) precipitation data, ASCAT (Advanced SCATterometter) soil moisture data, NDVI (Normalized Difference Vegetation Index) ), Land Surface Temperature (LST), and Digital Elevation Model (DEM) as input variables, and Global Land Data Assimilation System (GLDAS) soil moisture data as output variables, a soil moisture index downscaling model is created, The method may further include inputting the input variable converted into a grid size into the soil moisture index downscaling model to obtain the downscaled soil moisture index.
상기의 기술적 과제를 달성하기 위한 본 발명의 바람직한 실시예에 따른 컴퓨터 프로그램은 컴퓨터로 읽을 수 있는 기록 매체에 저장되어 상기한 산불 위험 지수 제공 방법 중 어느 하나를 컴퓨터에서 실행시킨다.The computer program according to a preferred embodiment of the present invention for achieving the above technical problem is stored in a computer-readable recording medium and executes any one of the methods for providing the forest fire risk index described above on the computer.
본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 장치 및 방법에 의하면, 한반도에 최적화된 산불 위험 지수 모델을 생성하고, 생성된 산불 위험 지수 모델을 이용하여 예보일에 대한 산불 위험 지수를 예보함으로써, 현장의 효율적 산불 대비(진화 자원의 전진 배치 등)를 통해 피해를 최소화하고, 나아가 산불 예방에 필요한 정보를 제공하여 산불 발생 빈도를 줄일 수 있다.According to the apparatus and method for providing a forest fire risk index according to a preferred embodiment of the present invention, by generating a forest fire risk index model optimized for the Korean Peninsula, and predicting the forest fire risk index for the forecast date using the generated forest fire risk index model, Damage can be minimized through efficient on-site forest fire preparation (forward deployment of firefighting resources, etc.)
본 발명의 효과들은 이상에서 언급한 효과들로 제한되지 않으며, 언급되지 않은 또 다른 효과들은 아래의 기재로부터 통상의 기술자에게 명확하게 이해될 수 있을 것이다.Effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.
도 1은 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 장치를 설명하기 위한 블록도이다.1 is a block diagram illustrating an apparatus for providing a forest fire risk index according to a preferred embodiment of the present invention.
도 2는 본 발명의 바람직한 실시예에 따른 토양 수분 지수 다운스케일링 모델을 설명하기 위한 도면이다.2 is a view for explaining a soil moisture index downscaling model according to a preferred embodiment of the present invention.
도 3은 본 발명의 바람직한 실시예에 따른 토양 수분 지수 다운스케일링 모델의 결과를 설명하기 위한 도면이다.3 is a view for explaining the results of the soil moisture index downscaling model according to a preferred embodiment of the present invention.
도 4는 본 발명의 바람직한 실시예에 따른 ASCAT 토양 수분 자료를 제외한 토양 수분 지수 다운스케일링 모델의 결과를 설명하기 위한 도면이다.4 is a view for explaining the results of the soil moisture index downscaling model excluding the ASCAT soil moisture data according to a preferred embodiment of the present invention.
도 5는 본 발명의 바람직한 실시예에 따른 최종 다운스케일링된 토양 수분 지수를 설명하기 위한 도면으로, 도 5의 좌측은 제1 토양 수분 지수 다운스케일링 모델의 결과를 나타내고, 도 5의 우측은 제1 토양 수분 지수 다운스케일링 모델의 결과에서 누락된 부분을 제2 토양 수분 지수 다운스케일링 모델의 결과로 대체한 것을 나타낸다.5 is a view for explaining the final downscaled soil moisture index according to a preferred embodiment of the present invention. The left side of FIG. 5 shows the results of the first soil moisture index downscaling model, and the right side of FIG. 5 shows the first It shows that the missing part in the result of the soil moisture index downscaling model is replaced with the result of the second soil moisture index downscaling model.
도 6은 본 발명의 바람직한 실시예에 따른 가뭄 인자를 설명하기 위한 도면이다.6 is a view for explaining a drought factor according to a preferred embodiment of the present invention.
도 7은 본 발명의 바람직한 실시예에 따른 가중치를 적용한 가뭄 지수 모델의 결과를 설명하기 위한 도면이다.7 is a diagram for explaining a result of a drought index model to which weights are applied according to a preferred embodiment of the present invention.
도 8은 본 발명의 바람직한 실시예에 따른 산불 다발 지역 지도를 설명하기 위한 도면이다.8 is a view for explaining a map of a forest fire frequent area according to a preferred embodiment of the present invention.
도 9는 본 발명의 바람직한 실시예에 따른 FFMC를 산불 위험 지수의 팩터로 이용한 이유를 설명하기 위한 도면으로, 도 9의 (a)는 FFMC를 2015년 월별 산불 개수와 비교한 것이고, 도 9의 (b)는 FFMC를 2015년 10일별 산불 개수와 비교한 것이다.9 is a view for explaining the reason for using the FFMC as a factor of the forest fire risk index according to a preferred embodiment of the present invention. (b) compares FFMC with the number of wildfires by 10 days in 2015.
도 10은 본 발명의 바람직한 실시예에 따른 수정된 FFMC와 종래의 FFMC의 공간적 분포를 비교한 결과를 설명하기 위한 도면이다.10 is a view for explaining a result of comparing the spatial distribution of a modified FFMC according to a preferred embodiment of the present invention and a conventional FFMC.
도 11은 본 발명의 바람직한 실시예에 따른 수정된 FFMC와 종래의 FFMC를 월별 산불 개수와 비교한 결과를 설명하기 위한 도면이다.11 is a view for explaining a result of comparing the number of forest fires per month between the modified FFMC and the conventional FFMC according to a preferred embodiment of the present invention.
도 12는 본 발명의 바람직한 실시예에 따른 산불 위험 지수의 획득에 이용되는 가뭄 지수를 설명하기 위한 도면이다.12 is a view for explaining a drought index used to obtain a forest fire risk index according to a preferred embodiment of the present invention.
도 13은 본 발명의 바람직한 실시예에 따른 산불 위험 지수의 획득에 이용되는 제1 월별 가중치를 설명하기 위한 도면이다.13 is a view for explaining a first monthly weight used to obtain a forest fire risk index according to a preferred embodiment of the present invention.
도 14는 본 발명의 바람직한 실시예에 따른 산불 위험 지수의 획득에 이용되는 제2 월별 가중치를 설명하기 위한 도면이다.14 is a diagram for explaining a second monthly weight used to obtain a forest fire risk index according to a preferred embodiment of the present invention.
도 15는 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 방법을 설명하기 위한 흐름도이다.15 is a flowchart for explaining a method for providing a forest fire risk index according to a preferred embodiment of the present invention.
이하, 첨부된 도면을 참조하여 본 발명의 실시 예를 상세히 설명한다. 본 발명의 이점 및 특징, 그리고 그것들을 달성하는 방법은 첨부되는 도면과 함께 상세하게 후술되어 있는 실시 예들을 참조하면 명확해질 것이다. 그러나 본 발명은 이하에서 게시되는 실시예들에 한정되는 것이 아니라 서로 다른 다양한 형태로 구현될 수 있으며, 단지 본 실시예들은 본 발명의 게시가 완전하도록 하고, 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자에게 발명의 범주를 완전하게 알려주기 위해 제공되는 것이며, 본 발명은 청구항의 범주에 의해 정의될 뿐이다. 명세서 전체에 걸쳐 동일 참조 부호는 동일 구성 요소를 지칭한다.Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention, and a method for achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments published below, but may be implemented in various different forms, and only these embodiments make the publication of the present invention complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.
다른 정의가 없다면, 본 명세서에서 사용되는 모든 용어(기술 및 과학적 용어를 포함)는 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자에게 공통적으로 이해될 수 있는 의미로 사용될 수 있을 것이다. 또 일반적으로 사용되는 사전에 정의되어 있는 용어들은 명백하게 특별히 정의되어 있지 않는 한 이상적으로 또는 과도하게 해석되지 않는다.Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly defined in particular.
본 명세서에서 "제1", "제2" 등의 용어는 하나의 구성요소를 다른 구성요소로부터 구별하기 위한 것으로, 이들 용어들에 의해 권리범위가 한정되어서는 아니 된다. 예를 들어, 제1 구성요소는 제2 구성요소로 명명될 수 있고, 유사하게 제2 구성요소도 제1 구성요소로 명명될 수 있다.In the present specification, terms such as “first” and “second” are for distinguishing one component from other components, and the scope of rights should not be limited by these terms. For example, a first component may be termed a second component, and similarly, a second component may also be termed a first component.
본 명세서에서 각 단계들에 있어 식별부호(예를 들어, a, b, c 등)는 설명의 편의를 위하여 사용되는 것으로 식별부호는 각 단계들의 순서를 설명하는 것이 아니며, 각 단계들은 문맥상 명백하게 특정 순서를 기재하지 않는 이상 명기된 순서와 다르게 일어날 수 있다. 즉, 각 단계들은 명기된 순서와 동일하게 일어날 수도 있고 실질적으로 동시에 수행될 수도 있으며 반대의 순서대로 수행될 수도 있다.In the present specification, identification symbols (eg, a, b, c, etc.) in each step are used for convenience of description, and identification symbols do not describe the order of each step, and each step is clearly Unless a specific order is specified, the order may differ from the specified order. That is, each step may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.
본 명세서에서, "가진다", "가질 수 있다", "포함한다" 또는 "포함할 수 있다"등의 표현은 해당 특징(예: 수치, 기능, 동작, 또는 부품 등의 구성요소)의 존재를 가리키며, 추가적인 특징의 존재를 배제하지 않는다.In this specification, expressions such as “have”, “may have”, “include” or “may include” indicate the existence of a corresponding feature (eg, a numerical value, function, operation, or component such as a part). and does not exclude the presence of additional features.
또한, 본 명세서에 기재된 '~부'라는 용어는 소프트웨어 또는 FPGA(field-programmable gate array) 또는 ASIC과 같은 하드웨어 구성요소를 의미하며, '~부'는 어떤 역할들을 수행한다. 그렇지만 '~부'는 소프트웨어 또는 하드웨어에 한정되는 의미는 아니다. '~부'는 어드레싱할 수 있는 저장 매체에 있도록 구성될 수도 있고 하나 또는 그 이상의 프로세서들을 재생시키도록 구성될 수도 있다. 따라서, 일 예로서 '~부'는 소프트웨어 구성요소들, 객체지향 소프트웨어 구성요소들, 클래스 구성요소들 및 태스크 구성요소들과 같은 구성요소들과, 프로세스들, 함수들, 속성들, 프로시저들, 서브루틴들, 프로그램 코드의 세그먼트들, 드라이버들, 펌웨어, 마이크로코드, 회로, 데이터 구조들 및 변수들을 포함한다. 구성요소들과 '~부'들 안에서 제공되는 기능은 더 작은 수의 구성요소들 및 '~부'들로 결합되거나 추가적인 구성요소들과 '~부'들로 더 분리될 수 있다.In addition, the term '~ unit' as used herein means software or a hardware component such as a field-programmable gate array (FPGA) or ASIC, and '~ unit' performs certain roles. However, '-part' is not limited to software or hardware. '~' may be configured to reside on an addressable storage medium or may be configured to refresh one or more processors. Accordingly, as an example, '~' indicates components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data structures and variables. The functions provided in the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'.
이하에서 첨부한 도면을 참조하여 본 발명에 따른 산불 위험 지수 제공 장치 및 방법의 바람직한 실시예에 대해 상세하게 설명한다.Hereinafter, a preferred embodiment of the apparatus and method for providing a forest fire risk index according to the present invention will be described in detail with reference to the accompanying drawings.
먼저, 도 1을 참조하여 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 장치에 대하여 설명한다.First, an apparatus for providing a forest fire risk index according to a preferred embodiment of the present invention will be described with reference to FIG. 1 .
도 1은 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 장치를 설명하기 위한 블록도이다.1 is a block diagram illustrating an apparatus for providing a forest fire risk index according to a preferred embodiment of the present invention.
도 1을 참조하면, 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 장치(100)는 한반도에 최적화된 산불 위험 지수 모델을 생성하고, 생성된 산불 위험 지수 모델을 이용하여 예보일에 대한 산불 위험 지수를 예보한다.Referring to FIG. 1 , the apparatus 100 for providing a forest fire risk index according to a preferred embodiment of the present invention generates a forest fire risk index model optimized for the Korean Peninsula, and uses the generated forest fire risk index model to predict forest fire risk for a forecast date. predict the index.
이를 위해, 산불 위험 지수 제공 장치(100)는 토양 수분 지수 획득부(110), 가뭄 지수 획득부(130), 산불 위험 지수 획득부(150) 및 예보부(170)를 포함할 수 있다.To this end, the forest fire risk index providing apparatus 100 may include a soil moisture index obtaining unit 110 , a drought index obtaining unit 130 , a forest fire risk index obtaining unit 150 , and a forecasting unit 170 .
토양 수분 지수 획득부(110)는 기계 학습 알고리즘을 기반으로, TRMM(Tropical Rainfall Measuring Mission) 강수 자료, ASCAT(Advanced SCATterometter) 토양 수분 자료, NDVI(Normalised Difference Vegetation Index), LST(Land Surface Temperature) 및 DEM(digital Elevation Model)을 입력 변수로 하고, GLDAS(Global Land Data Assimilation System) 토양 수분 자료를 출력 변수로 하는, 토양 수분 지수 다운스케일링 모델을 생성한다.The soil moisture index acquisition unit 110 is based on a machine learning algorithm, TRMM (Tropical Rainfall Measuring Mission) precipitation data, ASCAT (Advanced SCATterometter) soil moisture data, NDVI (Normalized Difference Vegetation Index), LST (Land Surface Temperature) and A soil moisture index downscaling model is generated using a digital elevation model (DEM) as an input variable and global land data assimilation system (GLDAS) soil moisture data as an output variable.
여기서, 기계 학습 알고리즘은 랜덤 포레스트(random forest, RF), 서포트 벡터 회귀 분석(support vector regression, SVR) 및 인공 신경망(Artifical Neural Network, ANN) 중 하나를 이용할 수 있다. 특히, 본 발명은 랜덤 포레스트(RF)를 이용하여 토양 수분 지수 다운스케일링 모델을 생성할 수 있다.Here, the machine learning algorithm may use one of a random forest (RF), support vector regression (SVR), and an artificial neural network (ANN). In particular, the present invention can generate a soil moisture index downscaling model using a random forest (RF).
이때, 토양 수분 지수 획득부(110)는 자료 간 공간 해상도의 통일성을 위해, GLDAS 토양 수분 자료의 격자 크기와 동일한 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여 토양 수분 지수 다운스케일링 모델을 생성한다.At this time, the soil moisture index acquisition unit 110 uses, as training data, the upscaled data to a grid size of 25 km, which is the same as the grid size of the GLDAS soil moisture data, as training data for the unity of spatial resolution between the data. create
그리고, 토양 수분 지수 획득부(110)는 1km의 격자 크기로 변환된 입력 변수를 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 토양 수분 지수를 획득한다.Then, the soil moisture index acquisition unit 110 obtains the soil moisture index downscaled to the grid size of 1 km by inputting the input variable converted to the 1km grid size to the soil moisture index downscaling model.
보다 자세하게 설명하면, 토양 수분 지수 획득부(110)는 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, TRMM 강수 자료, ASCAT 토양 수분 자료, NDVI, LST 및 DEM을 입력 변수로 하고, GLDAS 토양 수분 자료를 출력 변수로 하는, 제1 토양 수분 지수 다운스케일링 모델을 생성할 수 있다.In more detail, the soil moisture index acquisition unit 110 uses the data upscaled to a grid size of 25 km as training data, and uses TRMM precipitation data, ASCAT soil moisture data, NDVI, LST and DEM as input variables, Using the GLDAS soil moisture data as an output variable, a first soil moisture index downscaling model may be generated.
그리고, 토양 수분 지수 획득부(110)는 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, TRMM 강수 자료, NDVI, LST 및 DEM을 입력 변수로 하고, GLDAS 토양 수분 자료를 출력 변수로 하는, 제2 토양 수분 지수 다운스케일링 모델을 생성할 수 있다. 즉, 토양 수분 지수 획득부(110)는 제1 토양 수분 지수 다운스케일링 모델의 입력 변수들 중에서 ASCAT 토양 수분 자료를 제외한 나머지 입력 변수들을 이용하여 제2 토양 수분 지수 다운스케일링 모델을 생성할 수 있다.Then, the soil moisture index acquisition unit 110 uses the upscaled data to a grid size of 25 km as training data, TRMM precipitation data, NDVI, LST, and DEM as input variables, and GLDAS soil moisture data as output variables. , it is possible to generate a second soil moisture index downscaling model. That is, the soil moisture index acquisition unit 110 may generate the second soil moisture index downscaling model by using the remaining input variables except for the ASCAT soil moisture data among the input variables of the first soil moisture index downscaling model.
그런 다음, 토양 수분 지수 획득부(110)는 1km의 격자 크기로 변환된 입력 변수를 제1 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 제1 토양 수분 지수를 획득하고, 1km의 격자 크기로 변환된 입력 변수를 제2 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 제2 토양 수분 지수를 획득하며, 제1 토양 수분 지수에서 누락된 부분은 제2 토양 수분 지수로 대체하여 1km의 격자 크기로 다운스케일링된 최종 토양 수분 지수를 획득할 수 있다.Then, the soil moisture index acquisition unit 110 inputs the input variable converted to a grid size of 1 km into the first soil moisture index downscaling model to obtain a first soil moisture index downscaled to a grid size of 1 km, The input variable converted to a grid size of 1 km is input to the second soil moisture index downscaling model to obtain a second soil moisture index downscaled to a grid size of 1 km, and the missing part in the first soil moisture index is the second By substituting the soil moisture index, the final soil moisture index downscaled to a grid size of 1 km can be obtained.
가뭄 지수 획득부(130)는 토양 수분 지수 획득부(110)를 통해 획득된 1km의 격자 크기로 다운스케일링된 토양 수분 지수, NDWI(Normalized Different Water Index) 및 TCI(Temperature Condition Index)를 이용하여 가뭄 지수를 획득한다.The drought index acquisition unit 130 uses the soil moisture index downscaled to a grid size of 1 km obtained through the soil moisture index acquisition unit 110, NDWI (Normalized Different Water Index), and TCI (Temperature Condition Index) during drought get an index
즉, 가뭄 지수 획득부(130)는 아래의 식을 통해 가뭄 지수를 획득할 수 있다.That is, the drought index obtaining unit 130 may obtain the drought index through the following equation.
가뭄 지수 = 0.4 * (다운스케일링된 토양 수분 지수) + 0.3 * (NDWI) + 0.3 * (TCI)Drought Index = 0.4 * (Downscaled Soil Moisture Index) + 0.3 * (NDWI) + 0.3 * (TCI)
보다 자세하게 설명하면, 가뭄 지수 획득부(130)는 아래의 가뭄 관련 인자들 중에서 가뭄과 높은 상관성을 보인 인자들인 다운스케일링된 토양 수분 지수, NDWI 및 TCI를 이용하여 가뭄 지수를 획득할 수 있다.In more detail, the drought index acquisition unit 130 may acquire the drought index by using the downscaled soil moisture index, NDWI, and TCI, which are factors showing a high correlation with drought among the following drought-related factors.
- 1km의 격자 크기로 다운스케일링된 토양 수분 지수- Soil moisture index downscaled to a grid size of 1 km
- NDDI(Normalized Different Drought Index)- NDDI (Normalized Different Drought Index)
- NDWI(Normalized Different Water Index)- NDWI (Normalized Different Water Index)
- NMDI(Normalized Multi-band Drought Index)- NMDI (Normalized Multi-band Drought Index)
- TCI(Temperature Condition Index)- TCI (Temperature Condition Index)
- VCI(Vegetation Condition Index)- VCI (Vegetation Condition Index)
- TRMM(Tropical Rainfall Measuring Mission) 1(1주 누적 강수량) / TRMM 2(2주 누적 강수량)- TRMM (Tropical Rainfall Measuring Mission) 1 (accumulated precipitation per week) / TRMM 2 (accumulated precipitation in 2 weeks)
물론, 가뭄 지수 획득부(130)는 아래와 같은 3개의 식을 통해 3개의 가뭄 지수를 획득하고, 획득한 3개의 가뭄 지수의 평균값을 최종 가뭄 지수로 획득할 수 있도 있다.Of course, the drought index acquisition unit 130 may obtain three drought indices through the following three equations, and obtain an average value of the obtained three drought indices as the final drought index.
- 식 1 : 위에서 설명한 가뭄 지수 식- Equation 1: The drought exponential equation described above
- 식 2 : 가뭄 지수 = 0.4 * (다운스케일링된 토양 수분 지수) + 0.2 * (NDWI) + 0.4 * (TRMM)- Equation 2: Drought index = 0.4 * (downscaled soil moisture index) + 0.2 * (NDWI) + 0.4 * (TRMM)
- 식 3 : 가뭄 지수 = 0.3 * (다운스케일링된 토양 수분 지수) + 0.2 * (NDWI) + 0.3 * (TRMM) + 0.1 * (TCI)- Equation 3: Drought index = 0.3 * (downscaled soil moisture index) + 0.2 * (NDWI) + 0.3 * (TRMM) + 0.1 * (TCI)
한편, 가뭄 지수 획득부(130)는 One-Class SVM을 이용하여 가뭄 지수 모델을 생성하고, 생성된 가뭄 지수 모델을 이용하여 가뭄 지수를 획득할 수도 있으나, 본 발명에 따른 가뭄 지수 획득부(130)는 위의 식을 통해 가뭄 지수를 획득한다.On the other hand, the drought index obtaining unit 130 may generate a drought index model using the One-Class SVM, and may obtain the drought index using the generated drought index model, but the drought index obtaining unit 130 according to the present invention ) obtains the drought index through the above equation.
물론, 가뭄 지수 획득부(130)는 다운스케일링된 토양 수분 지수, NDWI 및 TCI를 이용하여 위의 식 1을 통해 제1 가뭄 지수를 획득하고, One-Class SVM을 이용하여 생성된 가뭄 지수 모델을 통해 제2 가뭄 지수를 획득하며, 획득한 제1 가뭄 지수 및 제2 가뭄 지수의 평균값을 최종 가뭄 지수로 획득할 수도 있다. 이때, 가뭄 지수 획득부(130)는 위의 식 1 ~ 식 3을 통해 획득된 3개의 가뭄 지수의 평균값을 제1 가뭄 지수로 이용할 수 있다.Of course, the drought index acquisition unit 130 obtains the first drought index through Equation 1 above using the downscaled soil moisture index, NDWI, and TCI, and uses the One-Class SVM to generate the drought index model. A second drought index may be obtained through the process, and an average value of the obtained first and second drought indexes may be obtained as a final drought index. In this case, the drought index acquisition unit 130 may use the average value of the three drought indices obtained through Equations 1 to 3 above as the first drought index.
산불 위험 지수 획득부(150)는 산불 다발 지역 지도, 수정된 FFMC(Fine Fuel Moisture Code), 가뭄 지수 획득부(130)를 통해 획득된 가뭄 지수 및 월별 가중치를 이용하여 산불 위험 지수를 획득한다. The forest fire risk index acquisition unit 150 obtains a forest fire risk index using the drought index and monthly weights obtained through the forest fire frequent area map, the modified Fine Fuel Moisture Code (FFMC), and the drought index acquisition unit 130 .
여기서, 월별 가중치는 과거에 발생한 모든 산불을 기반으로 획득한 월별 산불 발생 건수 비율을 이용하여, 월별 산불 발생 건수가 많을수록 더 큰 가중치가 부여될 수 있다. 예컨대, 월별 가중치는 과거에 발생한 모든 산불을 기반으로 월별 산불 발생 건수 비율에 따라 월별 산불 발생 건수가 많을 수록 더 큰 가중치를 부여하는 제1 월별 가중치이거나, 과거에 발생한 모든 산불을 기반으로 월별 산불 발생 건수가 가장 많은 특정 월(3월~5월)에만 가중치를 부여하는 제2 월별 가중치일 수 있다. 특히, 본 발명은 제1 월별 가중치를 이용하여 산불 위험 지수를 획득할 수 있다.Here, the monthly weight may be given a greater weight as the number of monthly forest fires increases, using the ratio of the number of monthly wildfires obtained based on all forest fires that have occurred in the past. For example, the monthly weight is the first monthly weight that gives a greater weight as the number of monthly wildfires increases according to the ratio of the number of monthly wildfires based on all forest fires that have occurred in the past It may be a second monthly weight that weights only a specific month (March-May) with the highest number of cases. In particular, the present invention can obtain a forest fire risk index by using the first monthly weight.
그리고, 수정된 FFMC는 상대 습도, 정오에 측정한 강수량, 온도, 풍속을 이용하여 계산된 당일의 평형 수분량, 건조율 및 최소 수분량을 기반으로 FFMC를 산출하는 종래의 FFMC에서, 강수 영향 범위을 수정한 FFMC를 말한다. 즉, 수정된 FFMC는 종래의 FFMC에서, FFMC 초기값, 강수량 기준값, FFMC 기준값 및 건조율을 계산하는 식의 계수가 수정되고, 전날 수분량을 계산하는 식의 계수가 수정되며, 최소 수분량을 이용하여 FFMC 값을 계산하는 식의 계수가 수정되고, 정오에 측정한 강수량이 아닌 하루 누적 강수량이 이용되며, 강수량 기준값이 종래의 FFMC보다 커진 FFMC를 말한다.And, the modified FFMC is the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content of the day calculated using the relative humidity, precipitation measured at noon, temperature, and wind speed. say FFMC. That is, in the modified FFMC, the coefficient of the formula for calculating the FFMC initial value, the precipitation reference value, the FFMC reference value and the drying rate is modified in the conventional FFMC, the coefficient of the formula calculating the moisture content of the previous day is modified, and the minimum moisture content is used It refers to an FFMC in which the coefficient of the equation for calculating the FFMC value is modified, the accumulated precipitation per day is used instead of the precipitation measured at noon, and the precipitation reference value is larger than that of the conventional FFMC.
즉, 산불 위험 지수 획득부(150)는 아래의 식을 통해 산불 위험 지수를 획득할 수 있다.That is, the forest fire risk index acquisition unit 150 may acquire the forest fire risk index through the following equation.
산불 위험 지수 = (산불 다발 지역 지도 + 0.5) * (수정된 FFMC) * (1.5 - 가뭄 지수) * (월별 가중치)Wildfire Risk Index = (Wildfire Hotspot Map + 0.5) * (Adjusted FFMC) * (1.5 - Drought Index) * (Monthly Weighted)
이때, 산불 위험 지수 획득부(150)는 월별 가중치로 "제1 월별 가중치"를 이용하여 위의 식을 통해 제1 산불 위험 지수를 획득하고, 월변 가중치로 "제2 월별 가중치"를 이용하여 위의 식을 통해 제2 산불 위험 지수를 획득하며, 획득한 제1 산불 위험 지수 및 제2 산불 위험 지수의 평균값을 최종 산불 위험 지수로 획득할 수도 있다.At this time, the forest fire risk index acquisition unit 150 obtains the first forest fire risk index through the above formula using the “first monthly weight” as the monthly weight, and uses the “second monthly weight” as the monthly weight to obtain the above The second wildfire risk index is obtained through the ceremony, and the average value of the obtained first wildfire risk index and the second wildfire risk index may be obtained as the final forest fire risk index.
예보부(170)는 산불 위험 지수 획득부(150)를 통해 획득한 산불 위험 지수를 기반으로, 예보일에 대한 산불 위험 지수 값을 획득한다.The forecasting unit 170 acquires a forest fire risk index value for the forecast date based on the forest fire risk index obtained through the forest fire risk index obtaining unit 150 .
그러면, 도 2 내지 도 5를 참조하여 본 발명의 바람직한 실시예에 따른 토양 수분 지수 다운스케일링 모델에 대하여 보다 자세하게 설명한다.Then, a soil moisture index downscaling model according to a preferred embodiment of the present invention will be described in more detail with reference to FIGS. 2 to 5 .
본 발명에서는 한반도의 토양 수분 다운스케일링을 수행하기 위하여 2013년 ~ 2015년 기간 동안의 GLDAS(Global Land Data Assimilation System) 토양 수분 자료, ASCAT(Advanced SCATterometter) 토양 수분 자료, NDVI(Normalised Difference Vegetation Index), LST(Land Surface Temperature), DEM(Digital Elevation Model), 일간 TRMM(Tropical Rainfall Measuring Mission) 강수 자료를 사용한 5일, 7일 누적 강수량 자료를 사용하여 토양 수분 지수 다운스케일링 모델 구축 후 토양 수분 현장 관측 자료로 모델을 검증하였다.In the present invention, GLDAS (Global Land Data Assimilation System) soil moisture data, ASCAT (Advanced SCATterometter) soil moisture data, NDVI (Normalized Difference Vegetation Index), Field observation data of soil moisture after constructing a soil moisture index downscaling model using 5-day and 7-day cumulative precipitation data using LST (Land Surface Temperature), DEM (Digital Elevation Model), and daily TRMM (Tropical Rainfall Measuring Mission) precipitation data to verify the model.
먼저, 토양 수분 자료로 사용한 GLDAS는 Mosaic, Noah, 및 Community Land Model의 세 가지 지표 모델을 기반으로 한 자료 동화 데이터 시스템으로 본 발명에서는 세 지표 모델 중 Noah 모델을 사용하였다. Noah 모델은 25km 공간 해상도의 1cm ~ 10cm 토양층의 수분 자료를 일별 4회(03, 09, 15, 12시) 제공하여, 해당 토양수분 자료(m3/m3)를 일별로 평균하여 사용하였다. ASCAT에서 산출되는 토양 수분 자료는 하루 동안의 ascending, descending pass 자료를 일별로 평균하여 사용하였다. 보조 변수로 Terra 위성의 MODIS(Moderate resolution Imaging Spectroradiometer)로부터 산출되는 1km 공간 해상도의 16일 합성 NDVI 자료인 MOD13A2와 1km 공간 해상도의 8일 합성 LST 자료인 MOD11A2 산출물을 사용하였다. 또한, DEM은 90m의 공간 해상도를 갖는 SRTM(Shuttle Radar Topography Mission)의 전 지구 DEM 자료를 사용하였다. 강수량 자료의 경우 25km의 공간 해상도를 갖는 TRMM 3B42 일간 자료를 각각 5일, 7일 동안의 기간으로 누적하여 사용하였다. 농업진흥청에서 제공하는 토양 수분 현장 관측 자료(%)는 m3/m3로의 단위 변환 이후 모델의 검증을 위해 사용되었다. 현장 관측 자료를 제외한 모든 자료는 연구 지역 범위로 masking 후 사용되었으며, 단 LST와 NDVI 산출물의 경우 모자이크 이후 마스킹하여 사용하였다.First, GLDAS used as soil moisture data is a data assimilation data system based on three surface models of Mosaic, Noah, and Community Land Model. In the present invention, Noah model was used among the three surface models. The Noah model provided the moisture data of the 1 cm ~ 10 cm soil layer with a spatial resolution of 25 km 4 times a day (03, 09, 15, and 12:00), and the corresponding soil moisture data (m 3 /m 3 ) was averaged daily and used. For soil moisture data calculated by ASCAT, daily ascending and descending pass data were averaged and used. As auxiliary variables, MOD13A2, which is 16-day synthetic NDVI data with 1 km spatial resolution calculated from MODIS (Moderate Resolution Imaging Spectroradiometer) of Terra satellite, and MOD11A2 output, which is 8-day synthetic LST data with 1 km spatial resolution, was used. In addition, the DEM used the global DEM data of the Shuttle Radar Topography Mission (SRTM) with a spatial resolution of 90 m. In the case of precipitation data, TRMM 3B42 daily data with a spatial resolution of 25 km were accumulated over a period of 5 and 7 days, respectively. The soil moisture field observation data (%) provided by the Agricultural Promotion Agency was used to validate the model after unit conversion to m 3 /m 3 . All data except field observation data were used after masking in the range of the study area.
도 2는 본 발명의 바람직한 실시예에 따른 토양 수분 지수 다운스케일링 모델을 설명하기 위한 도면이다.2 is a view for explaining a soil moisture index downscaling model according to a preferred embodiment of the present invention.
도 2를 참조하면, 본 발명에서는 다양한 기계 학습 및 인공지능 기법을 활용하여 토양 수분 상세화를 위한 다운스케일링 모델을 개발하였다. 사용된 기계 학습 및 인공지능 방법으로는 랜덤 포레스트(RF), 서포트 벡터 회귀 분석(SVR) 및 ㅇ인공 신경망(ANN)의 세 가지 기법이 각각 사용되었다. GLDAS 토양 수분 자료를 종속 변수로 설정하고, 토양 수분 현장 관측 자료를 제외한 총 5개의 자료를 독립 변수로 설정하여 각 기법별로 다운스케일링 모델을 개발하였다. 자료 간 공간 해상도의 통일성을 위하여 모든 입력 자료는 GLDAS와 같은 격자 크기인 25km의 공간 해상도로 업스케일링 후 모델 구축에 적용되었다. 이후, 개발된 모델에 1km 격자 크기로 변환한 5개의 입력 자료를 적용하여 최종적으로 1km 격자의 다운스케일링 토양 수분 결과를 얻게 된다. 본 발명에서는 2013년 ~ 2014년 자료를 8:2의 비율로 훈련 자료와 검증 자료를 나누어 모델을 구축하고 추가적으로 동일한 기간 동안의 자료로 10-fold 교차 검증을 수행하였다. 또한, 각 모델을 통해 생산된 토양 수분 다운스케일링 결과는 농업진흥청의 현장 관측 토양 수분 자료와 비교하여 검증하였다.Referring to FIG. 2 , in the present invention, a downscaling model for soil moisture detailing was developed using various machine learning and artificial intelligence techniques. As the machine learning and artificial intelligence methods used, three techniques were used, respectively: random forest (RF), support vector regression analysis (SVR), and artificial neural network (ANN). The downscaling model was developed for each technique by setting the GLDAS soil moisture data as the dependent variable and setting a total of five data except the soil moisture field observation data as independent variables. For the unity of spatial resolution between data, all input data were applied to model building after upscaling to a spatial resolution of 25 km, the same grid size as GLDAS. After that, the 5 input data converted to the 1km grid size is applied to the developed model to finally obtain the downscaling soil moisture result of the 1km grid. In the present invention, the model was constructed by dividing the training data and the validation data by dividing the data from 2013 to 2014 at a ratio of 8:2, and additionally 10-fold cross-validation was performed with data for the same period. In addition, the soil moisture downscaling result produced through each model was verified by comparing it with the field observation soil moisture data of the Agricultural Promotion Administration.
도 3은 본 발명의 바람직한 실시예에 따른 토양 수분 지수 다운스케일링 모델의 결과를 설명하기 위한 도면이다.3 is a view for explaining the results of the soil moisture index downscaling model according to a preferred embodiment of the present invention.
한반도 지역 내 토양 수분 지수 다운스케일링 모델에 대하여 최적의 기법을 찾아보고자 세 가지 기법(RF, SVR, 및 ANN)을 이용하여 다운스케일링 모델을 개발 후 비교하였다. 도 3은 각 모델의 토양 수분 다운스케일링 결과를 산점도(scatter plot)로 나타낸 것으로, RF, ANN, SVR의 순서로 실제 변수의 값과 모델의 예측 값 사이의 상관계수 값이 컸으며, RMSE(Root Mean Square Error) 또한 값이 작게 나타났다. 특히, 교차 검증에 관한 산점도에서 RF 결과의 분포가 가장 좁게 나타났다. 세 모델 모두 전체적으로 높은 토양 수분 값에 대해서는 실제보다 낮게 예측하고 낮은 토양 수분 값에 대해서는 높게 예측하는 경향이 있었다. 이에, 본 발명에 따른 토양 수분 지수 다운스케일링 모델은 RF를 이용하여 생성하였다.To find the optimal method for the soil moisture index downscaling model in the Korean Peninsula, three methods (RF, SVR, and ANN) were used to develop and compare the downscaling model. 3 is a scatter plot showing the soil moisture downscaling results of each model. In the order of RF, ANN, and SVR, the correlation coefficient value between the actual variable value and the model predicted value was large, and the RMSE (Root Mean Square Error) also showed a small value. In particular, the distribution of RF results was the narrowest in the scatterplot related to cross-validation. All three models tended to predict lower-than-actual values for high soil moisture values and high for low soil moisture values overall. Accordingly, the soil moisture index downscaling model according to the present invention was generated using RF.
도 4는 본 발명의 바람직한 실시예에 따른 ASCAT 토양 수분 자료를 제외한 토양 수분 지수 다운스케일링 모델의 결과를 설명하기 위한 도면이고, 도 5는 본 발명의 바람직한 실시예에 따른 최종 다운스케일링된 토양 수분 지수를 설명하기 위한 도면으로, 도 5의 좌측은 제1 토양 수분 지수 다운스케일링 모델의 결과를 나타내고, 도 5의 우측은 제1 토양 수분 지수 다운스케일링 모델의 결과에서 누락된 부분을 제2 토양 수분 지수 다운스케일링 모델의 결과로 대체한 것을 나타낸다.Figure 4 is a view for explaining the results of the soil moisture index downscaling model excluding the ASCAT soil moisture data according to a preferred embodiment of the present invention, Figure 5 is the final downscaled soil moisture index according to a preferred embodiment of the present invention As a diagram for explaining , the left side of FIG. 5 shows the results of the first soil moisture index downscaling model, and the right side of FIG. 5 shows the missing part from the results of the first soil moisture index downscaling model with the second soil moisture index It represents substitution with the result of the downscaling model.
토양 수분 지수 다운스케일링 모델의 결과가 제주도 지역과 일부 해안선 근처에 대해 누락되는 것을 확인할 수 있다. 이는 입력 변수로 사용된 25km 공간 해상도의 ASCAT 토양 수분 자료의 값 여부에 따른 것이다. 해당 누락 문제를 해결하기 위하여 위에서 언급한 토양 수분 다운스케일링 방법에서 ASCAT을 입력 변수에서 제외한 총 4개의 입력 변수로 토양 수분 지수 다운스케일링 모델을 추가로 구축하여, 원 모델에서 ASCAT 자료로 인해 누락되는 부분을 추가 모델의 결과값으로 대체하고자 하였다. 도 4 및 도 5는 각각 추가 모델의 결과 성능과 토양 수분 지도 예시를 보여주고 있다.It can be seen that the results of the soil moisture index downscaling model are missing for the Jeju Island area and near some coastlines. This depends on the value of ASCAT soil moisture data with a spatial resolution of 25 km used as an input variable. In order to solve the omission problem, a soil moisture index downscaling model was additionally built with a total of four input variables excluding ASCAT from the input variables in the soil moisture downscaling method mentioned above, and the part missing due to ASCAT data in the original model was to be replaced with the result of the additional model. 4 and 5 show examples of the resultant performance and soil moisture map of the additional model, respectively.
각 토양 수분 지수 다운스케일링 모델의 결과를 검증하기 위하여 농업진흥청에서 제공하는 현장 관측 기반의 토양 수분 자료와 비교 검증을 수행하였다. 검증에 사용된 관측소의 토양 수분 자료는 토양 수분 지수 다운스케일링 모델의 결과와 검증하기 위하여 시계열 분석을 수행하였다. 시계열 분석 수행 결과, 관측소 모두 토양 수분의 증감 패턴이 유사하게 나타나는 것을 확인하였다.To verify the results of each soil moisture index downscaling model, comparison verification was performed with soil moisture data based on field observations provided by the Agricultural Promotion Administration. Time series analysis was performed to verify the soil moisture data of the observatory used for verification with the results of the soil moisture index downscaling model. As a result of time series analysis, it was confirmed that the soil moisture increase/decrease pattern was similar at all observation stations.
그러면, 도 6 및 도 7을 참조하여 본 발명의 바람직한 실시예에 따른 가뭄 지수에 대하여 보다 자세하게 설명한다.Then, the drought index according to a preferred embodiment of the present invention will be described in more detail with reference to FIGS. 6 and 7 .
우리나라에서 산불이 발생하는 주요 인자로는 입산자 실화, 담배꽁초 등이 있으며 가뭄으로 인한 산불 발생은 극히 드물다. 하지만, 가뭄의 상태일 때 산불이 발생하게 되면 그 피해(면적)가 가중될 수 있다. 따라서, 본 발명에서는 2013년부터 2018년까지 1ha 이상인 실제 산불 발생 자료를 이용하여 가뭄과 산불의 상관성을 분석하였다. 추후, 산불 위험 지수 개발에 사용하기 위해 실시간으로 가용한 위성 자료를 이용하였다. 사용된 가뭄 관련 인자로는 위에서 언급한 토양 수분 다운스케일링 자료와 NDDI(Normalized Different Drought Index), NDWI(Normalized Different Water Index) 5, 6, 7(SWIR band 사용에 따라 5, 6, 7로 나뉨), NMDI(Normalized Multi-band Drought Index), TCI(Temperature Condition Index), VCI(Vegetation Condition Index), TRMM 1, 2(1주 및 2주 누적 강수량) 자료이다. 아래의 식은 MODIS를 기반(MODIS band 기준)으로 나타내어 졌다.The main factors that cause wildfires in Korea include misfires of mountain climbers and cigarette butts, and the occurrence of wildfires due to drought is extremely rare. However, if a forest fire occurs during a drought, the damage (area) may be increased. Therefore, in the present invention, the correlation between drought and forest fires was analyzed using data on actual wildfire occurrence of 1 ha or more from 2013 to 2018. Later, satellite data available in real time were used to develop the forest fire risk index. The drought-related factors used include the above-mentioned soil moisture downscaling data, NDDI (Normalized Different Drought Index), NDWI (Normalized Different Water Index) 5, 6, 7 (Divided into 5, 6, 7 depending on the use of SWIR band) , NMDI (Normalized Multi-band Drought Index), TCI (Temperature Condition Index), VCI (Vegetation Condition Index), TRMM 1 and 2 (accumulated precipitation for one and two weeks) data. The formula below is expressed based on MODIS (based on MODIS band).
NDDI = (NDVI - NDWI) / (NDVI + NDWI)NDDI = (NDVI - NDWI) / (NDVI + NDWI)
NDWI = (band2 - SWIR) / (band2 + SWIR)NDWI = (band2 - SWIR) / (band2 + SWIR)
NMDI = (band2 - (band6 - band7)) / (band2 + (band6-band7))NMDI = (band2 - (band6 - band7)) / (band2 + (band6-band7))
도 6은 본 발명의 바람직한 실시예에 따른 가뭄 인자를 설명하기 위한 도면이다.6 is a view for explaining a drought factor according to a preferred embodiment of the present invention.
산불 발생 면적이 1 ha 이상(도 6의 좌측), 10 ha 이상(도 6의 우측)인 기준으로 각 인자 및 지수의 값 분포를 분석해본 결과 도 6과 같은 결과를 나타내었다. 값이 1에 가까울수록 가뭄이 아닌 상태를, 0에 가까울수록 가뭄이 심각함을 의미한다. 1 ha이상에서는 1주 누적 강수량(TRMM 1)과 2주 누적 강수량(TRMM 2) 값의 범위가 가장 가뭄 현상을 잘 나타내었고, 순서대로 토양 수분(SM), NDWI 등이 상관성 있는 분포를 보였다. NDDI와 NMDI, VCI는 비가뭄에 가까운 값을 보여 산불 발생에는 상관성이 떨어지는 것을 보였다(도 6의 좌측). 10 ha 이상에도 1 ha와 같은 상관성을 보였으며 상대적으로 비가뭄인 경우가 적었다(도 6의 우측). 산불 면적이 50 ha 이상인 경우(13건) 각 인자별 평균값은 토양 수분이 0.37, NDDI 0.49, NDWI 5 0.32, NDWI 6 0.28, NDWI 7 0.38, NMDI 0.41, TCI 0.45, VCI 0.56, TRMM 1 0.01, TRMM 2 0.02를 나타내는 등 가뭄과 더 큰 상관성을 나타내었다.As a result of analyzing the value distribution of each factor and index based on a forest fire occurrence area of 1 ha or more (left side of FIG. 6) and 10 ha or more (right side of FIG. 6), the same results as those of FIG. 6 were obtained. A value closer to 1 means a non-drought state, and a value closer to 0 means more severe drought. Above 1 ha, the range of 1-week cumulative precipitation (TRMM 1) and 2-week cumulative precipitation (TRMM 2) values showed the most drought phenomenon, and soil moisture (SM) and NDWI showed a correlation distribution in that order. NDDI, NMDI, and VCI showed values close to non-drought, indicating that the correlation was poor with the occurrence of forest fires (left side of FIG. 6). It showed the same correlation as 1 ha even at more than 10 ha, and relatively few cases of non-drought (right side of FIG. 6). For forest fire area of 50 ha or more (13 cases), the average value for each factor is soil moisture 0.37, NDDI 0.49, NDWI 5 0.32, NDWI 6 0.28, NDWI 7 0.38, NMDI 0.41, TCI 0.45, VCI 0.56, TRMM 1 0.01, TRMM 2 showed a greater correlation with drought, such as 0.02.
본 발명에서는 상관성 분석을 통해 선정된 가뭄 인자에 가중치(weight)를 적용하는 방식과 기계 학습 종류 중 하나인 One-Class SVM을 적용하여 가뭄 지수 모델의 개발을 수행하였다. 높은 상관성을 보였던 토양 수분, NDWI, TCI, NMDI, TRMM을 이용하여 지수를 개발하였다.In the present invention, a drought index model was developed by applying a weight to the drought factor selected through correlation analysis and by applying One-Class SVM, one of the types of machine learning. Indices were developed using soil moisture, NDWI, TCI, NMDI, and TRMM, which showed a high correlation.
(1) 가중치 적용(1) weighting
상관성 분석을 통해 강수 인자가 가장 큰 영향이 있는 것으로 나타났다. 하지만, 강수량의 경우는 강수의 발생 유무에 따라 가뭄 지수가 극값을 나타내고 공간적으로 모든 지역에 가뭄 혹은 비가뭄을 나타내므로 가뭄 지수 개발에 필수적으로 사용하는 것은 적합하지 않은 것으로 판단되었다. 따라서, 아래의 [표 1]과 같이, 강수량 다음으로 상관성이 높았던 토양 수분 및 NDWI를 기준으로 다른 인자와 조합하였다.Through correlation analysis, it was found that the precipitation factor had the greatest influence. However, in the case of precipitation, the drought index shows an extreme value depending on whether or not precipitation occurs, and drought or non-drought in all regions spatially, so it was judged not to be necessarily used for the development of the drought index. Therefore, as shown in [Table 1] below, soil moisture and NDWI, which had the highest correlation after precipitation, were combined with other factors.
SchemeScheme EquationEquation
1One 0.7 * 토양 수분 지수 + 0.3 * NDWI0.7 * Soil Moisture Index + 0.3 * NDWI
22 0.4 * 토양 수분 지수 + 0.3 * NDWI + 0.3 * TCI0.4 * Soil Moisture Index + 0.3 * NDWI + 0.3 * TCI
33 0.4 * 토양 수분 지수 + 0.3 * NDWI + 0.3 * NMDI0.4 * Soil Moisture Index + 0.3 * NDWI + 0.3 * NMDI
44 0.4 * 토양 수분 지수 + 0.2 * NDWI + 0.4 * TRMM0.4 * Soil Moisture Index + 0.2 * NDWI + 0.4 * TRMM
55 0.3 * 토양 수분 지수 + 0.2 * NDWI + 0.3 * TRMM + 0.1 * TCI0.3 * Soil Moisture Index + 0.2 * NDWI + 0.3 * TRMM + 0.1 * TCI
도 7은 본 발명의 바람직한 실시예에 따른 가중치를 적용한 가뭄 지수 모델의 결과를 설명하기 위한 도면이다. 도 7은 실제 산불 발생에 대한 각 Scheme별 결과를 나타낸 것으로, 강수량 인자가 포함된 Scheme 4와 5는 다른 Scheme에 비해 심각한 가뭄 상태를 나타내었으며, 산불 피해 면적에 상관없이 가뭄 상태를 나타내었다. 하지만, 산불이 발생하지 않은 지역에 대해서도 가뭄 상태를 나타내었다. 또한, NMDI에 비해 TCI가 상대적으로 큰 상관성이 있으므로, 산불 위험 지수 개발에 강수 인자가 포함되어 있지 않은 Scheme 2와 강수 인자가 포함된 Scheme 4와 5를 산불 위험 지수 개발에 사용하였다.7 is a diagram for explaining a result of a drought index model to which weights are applied according to a preferred embodiment of the present invention. 7 shows the results of each scheme for actual wildfire occurrence, Schemes 4 and 5 including precipitation factors showed a severe drought state compared to other schemes, and showed a drought state irrespective of the area damaged by the forest fire. However, even in areas where wildfires did not occur, drought conditions were indicated. In addition, since TCI has a relatively large correlation compared to NMDI, Scheme 2 without precipitation factors and Scheme 4 and 5 with precipitation factors were used for forest fire risk index development.
(2) One-Class SVM 적용(2) One-Class SVM application
One-Class SVM은 기존의 이진 분류 및 다중 분류 SVM과 동일하게 초평면(hyperplane)을 이용하여 one class와 아웃 라이어를 구분한다. Margin Support vectors를 기준으로 내부 vectors는 class가 할당되고, 외부에 있는 vectors는 아웃 라이어로 구분된다.One-Class SVM uses a hyperplane to classify one class and outliers in the same way as the existing binary classification and multi-classification SVMs. Based on the margin support vectors, internal vectors are assigned a class, and external vectors are identified as outliers.
기존의 이진 분류를 사용하여 기계 학습 모델을 개발할 경우 산불 비발생 샘플 추출에 대한 개발자의 주관적인 견해가 포함되므로, 본 발명에서는 One-Class SVM을 통해 산불 발생과 관련된 가뭄 지수 개발을 시도하였다. kernel function은 Gaussian을 이용하였으며, 모델을 통해 산출된 스코어를 노멀라이징하여 결과를 도출하였다. 좁은 범위의 노멀라이징(One-Class SVM 1, 최소 : 0, 최대 : 0.5)과 넓은 범위의 노멀라이징(One-Class SVM 2, 최소 : 0, 최대 : 0.1)을 나누어 결과를 비교하였다. 비교 결과, 산불 피해 면적이 작을수록 One-Class SVM 모델은 비가뭄인 상태를 나타내었으며, 가중치를 적용했을 때보다 비가뭄의 면적이 높았다. 하지만, 앞서 언급했듯이 우리나라의 산불 발생은 대체적으로 인적 발화로 인한 것이므로 비가뭄인 상태에서 산불이 발생할 수 있다. 따라서, One-Class SVM의 결과 또한 산불 위험 지수 개발에 테스트하였다.When developing a machine learning model using the existing binary classification, the developer's subjective opinion on the sample extraction of non-existing forest fires is included, so in the present invention, we tried to develop a drought index related to the occurrence of forest fires through One-Class SVM. The kernel function used Gaussian, and the result was derived by normalizing the score calculated through the model. The results were compared by dividing the narrow range normalization (One-Class SVM 1, min: 0, max: 0.5) and wide range normalization (One-Class SVM 2, min: 0, max: 0.1). As a result of comparison, the smaller the area damaged by forest fires, the more non-drought in the One-Class SVM model, and the area of non-drought was higher than when weight was applied. However, as mentioned above, the occurrence of forest fires in Korea is largely due to human ignition, so wildfires can occur in the absence of drought. Therefore, the results of the One-Class SVM were also tested in the development of a forest fire risk index.
그러면, 도 8 내지 도 14를 참조하여 본 발명의 바람직한 실시예에 따른 산불 위험 지수에 대하여 보다 자세하게 설명한다.Then, the forest fire risk index according to a preferred embodiment of the present invention will be described in more detail with reference to FIGS. 8 to 14 .
도 8은 본 발명의 바람직한 실시예에 따른 산불 다발 지역 지도를 설명하기 위한 도면이다.8 is a view for explaining a map of a forest fire frequent area according to a preferred embodiment of the present invention.
산불에 취약한 곳의 정보를 추가하기 위해서 국립산림과학원에서 제공하는 산불 다발 지역 지도를 사용하였다. 산불 다발 지역 지도는 1991년부터 2015년까지 발생한 모든 산불(10,560건)에 대해 위치 정보를 수치 지도화한 자료로써, 이러한 위치 정보를 토대로 밀도 분석을 실시하여 산불이 자주 발생할 수 있는 우려 대상 지역을 선정한 지도이다. 산불 발생 다발 지역을 선정하기 위하여 평균 거리법과 최근린 분석 등을 실시하여 산불 간의 평균적인 거리를 추정하였고, Kernel이 최초 제시한 밀도 함수에 의해 산불 다발 지역을 최종적으로 선정하였다. 산불 발생 원인은 크게 입산자 실화, 논/밭두렁 소각, 쓰레기 소각, 성묘객 실화, 담뱃불 실화, 기타 등 6가지로 구분하였다. 1991년부터 2015년까지 연평균 422건의 산불이 발생하여 매년 2,102ha의 산림이 연소 되었으며, 가장 많은 산불이 발생했던 해는 2001년으로 총 778건의 산불이 발생하였고 960ha의 산림이 전소되었다. 산불 발생 건수가 가장 많은 지역은 부산광역시(477건)이었으며, 이어 서울(412건), 인천(391건), 울산(350건), 대구(285건), 대전(263건), 광주(203건) 등 대도시권역에서 산불 발생빈도가 높게 나타났다(도 8 참조). 월별로 산불이 가장 많이 발생한 시기는 4월로 3,250건의 산불이 발생하여 전체의 30.8%를 차지하였다. 원인별 산불 통계 현황을 보면 입산자 실화로 인한 산불이 4,392건으로 전체 산불 건수의 41.6%를 차지하였으며, 뒤를 이어 논/밭두렁 소각이 1,952건으로 18.5%, 쓰레기 소각이 830건(7.9%), 담뱃불 실화가 813건(7.7%) 순이었다.In order to add information on places vulnerable to wildfires, a map of areas prone to forest fires provided by the National Academy of Forestry and Science was used. The map of areas prone to forest fires is a numerical map of location information for all wildfires (10,560 cases) that occurred from 1991 to 2015. Based on this location information, density analysis is performed to identify areas of concern where wildfires may occur frequently. This is the selected map. In order to select an area with a high incidence of forest fires, the average distance method and nearest neighbor analysis were performed to estimate the average distance between forest fires, and the density function first suggested by Kernel was used to finally select the area with a high incidence of forest fires. The causes of forest fires were divided into six categories: true stories of mountain climbers, incineration of paddy fields/field headlands, incineration of garbage, true stories of cemetery guests, true stories of cigarette fires, and others. From 1991 to 2015, an annual average of 422 wildfires occurred, and 2,102 ha of forest was burned every year. The region with the highest number of wildfires was Busan Metropolitan City (477 cases), followed by Seoul (412 cases), Incheon (391 cases), Ulsan (350 cases), Daegu (285 cases), Daejeon (263 cases), and Gwangju (203 cases). case), the incidence of wildfires was high in metropolitan areas (see Fig. 8). The period when the most wildfires occurred by month was April, with 3,250 wildfires taking place, accounting for 30.8% of the total. Looking at the statistical status of forest fires by cause, 4,392 cases of wildfires caused by mishaps by mountain climbers accounted for 41.6% of the total forest fires, followed by incineration of paddy fields/bedheads at 1,952 cases (18.5%), garbage incineration (830 cases (7.9%), and cigarette fires). was followed by 813 cases (7.7%).
도 9는 본 발명의 바람직한 실시예에 따른 FFMC를 산불 위험 지수의 팩터로 이용한 이유를 설명하기 위한 도면으로, 도 9의 (a)는 FFMC를 2015년 월별 산불 개수와 비교한 것이고, 도 9의 (b)는 FFMC를 2015년 10일별 산불 개수와 비교한 것이다.9 is a view for explaining the reason for using the FFMC as a factor of the forest fire risk index according to a preferred embodiment of the present invention. (b) compares FFMC with the number of wildfires by 10 days in 2015.
캐나다 산불 기상 지수(Canada Fire Weather Index, CFWI)는 기온, 상대 습도, 풍속, 강수량과 같은 기상 정보를 이용하여 산출한 FFMC(Fine Fuel Moisture Code), DMC(Duff Moisture Code), DC(Drought Code), ISI(Initial Spread Index), BUI(Build Up Index) 정보를 종합하여 산출하는 기상 지수이다. FFMC는 지상의 임내 미세 연료의 수분량을 지수화하여 예측하며, DMC는 임내 표층 연료 층의 습도를 예측한다. DC는 깊은 유기물층과 지중의 굵은 연료의 수분을 예측함으로써 계절적인 가뭄과 지중화의 가능성을 예측하며, ISI는 FFMC와 풍속 인자를 결합하여 산출한다. 이 중 FFMC는 기온, 상대 습도, 풍속, 강수량 정보를 이용하여 미세 연료의 수분량을 예측하며, 범위는 0 ~ 99이다. 숫자가 클수록 발화 가능성이 높다는 것을 의미한다. 기존 연구 중 CFWI를 우리나라에 적용했을 때 최종 산출 지수인 CFWI보다 FFMC가 상관관계가 높으며, FFMC를 이용한 회귀분석 모형으로 산불 발생 확률을 예측한 결과 5% 수준의 통계적인 유의성을 가진다는 연구 결과(박흥석 외, 2009)가 있다. CFWI와 FFMC를 우리나라 기존 산불 지수인 DWI(Daily Weather Index)와 2015년 산불 기준으로 비교하였을 때(도 9 참조), FFMC가 CFWI보다 우리나라에 더 적합함을 알 수 있었으며, 본 발명에서는 FFMC를 사용하기로 결정하였다.The Canada Fire Weather Index (CFWI) is calculated using weather information such as temperature, relative humidity, wind speed, and precipitation. , ISI (Initial Spread Index), and BUI (Build Up Index) information is a meteorological index calculated by synthesizing information. FFMC predicts the moisture content of the fine fuel in the forest above ground, and DMC predicts the humidity of the surface fuel layer in the forest. DC predicts the likelihood of seasonal drought and geological formation by predicting the moisture of deep organic matter layers and coarse fuel in the ground, and ISI is calculated by combining FFMC and wind speed factors. Among them, FFMC predicts the moisture content of fine fuel using temperature, relative humidity, wind speed, and precipitation information, and the range is 0 to 99. A higher number means a higher probability of ignition. Among existing studies, when CFWI is applied to Korea, FFMC has a higher correlation than CFWI, which is the final index, and as a result of predicting the probability of forest fire with a regression analysis model using FFMC, it has a statistical significance of 5% ( Park Heung-seok et al., 2009). When CFWI and FFMC were compared with DWI (Daily Weather Index), an existing forest fire index in Korea, based on the 2015 forest fire (see FIG. 9), it was found that FFMC was more suitable for Korea than CFWI, and FFMC was used in the present invention. decided to do
도 10은 본 발명의 바람직한 실시예에 따른 수정된 FFMC와 종래의 FFMC의 공간적 분포를 비교한 결과를 설명하기 위한 도면이고, 도 11은 본 발명의 바람직한 실시예에 따른 수정된 FFMC와 종래의 FFMC를 월별 산불 개수와 비교한 결과를 설명하기 위한 도면이다.10 is a view for explaining the result of comparing the spatial distribution of the modified FFMC according to the preferred embodiment of the present invention and the conventional FFMC, and FIG. 11 is the modified FFMC according to the preferred embodiment of the present invention and the conventional FFMC It is a diagram to explain the result of comparing with the number of forest fires per month.
위에서 도 9를 통해 CFWI보다 FFMC가 우리나라에 더 적합함을 파악하여 FFMC를 본 발명에서 사용하기로 결정하였다. FFMC는 1970년대 개발되어서 이후 계속해서 업데이트해서 사용되고 있는 중이며, 보다 정확한 산불 위험 지수 모델의 생성을 위해서 기존 FFMC를 우리나라 환경에 최적화하는 과정을 진행하였다. FFMC는 상대 습도, 강수량, 온도, 풍속 자료를 이용해 당일의 평형 수분량, 건조율, 최소 수분량 등을 계산하여 최종적으로 FFMC를 산출한다. 이에 따라, 본 발명에서도 우리나라 환경에 맞춰 일부 계수를 수정하여 FFMC를 최적화하였다. 즉, FFMC 초기값, 강수량 기준값, FFMC 기준값, 건조율을 계산하는 식 계수를 수정하였으며, 전날 수분량을 계산하는 식과 최소 분량을 이용해 FFMC를 계산하는 식의 계수를 수정하였다. 1970년대 개발된 최초의 식과 현재 사용하고 있는 식을 비교해 계수들의 범위를 정한 후, 각 계수들의 범위 안에서 계수들을 수정하면서 우리나라 산불 개수와 면적과 비교하여서 최적의 계수들로 찾아내었다. 기존 FFMC는 정오 때 측정한 강수량을 사용하였지만, 본 발명에서는 daily FFMC를 만들기 때문에 하루 누적 강수량을 사용하였다. 강수량 자료를 순간 강수량에서 누적 강수량으로 바꿔서 사용함으로써 강수량 기준값을 증가시켰다. 도 10은 기존 FFMC와 최적화된 FFMC(즉, 본 발명에 따른 수정된 FFMC)의 공간적 분포를 비교한 결과로서, 강수량이 건조 정도를 결정하고 FFMC 계산에 중요한 변수이기 때문에 FFMC가 강수량의 패턴을 가장 많이 따르는 것을 확인할 수 있었다. FFMC를 우리나라 환경에 맞게 수정하면서 강수량에 많이 치우쳐진 기존 FFMC를 보다 완만하게 영향을 줄 수 있도록 수정하였다.Through FIG. 9, it was determined that FFMC is more suitable for Korea than CFWI, so that FFMC is used in the present invention. FFMC was developed in the 1970s and has been continuously updated since then, and in order to create a more accurate forest fire risk index model, the process of optimizing the existing FFMC for the Korean environment was carried out. FFMC calculates the equilibrium moisture content, drying rate, and minimum moisture content of the day using relative humidity, precipitation, temperature, and wind speed data, and finally calculates the FFMC. Accordingly, in the present invention, FFMC was optimized by modifying some coefficients according to the Korean environment. That is, the formula coefficients for calculating the FFMC initial value, the precipitation standard value, the FFMC standard value, and the drying rate were modified, and the coefficients of the formula for calculating the moisture content of the previous day and the formula for calculating the FFMC using the minimum amount were modified. After determining the range of coefficients by comparing the first formula developed in the 1970s with the formula currently used, the coefficients were modified within the range of each coefficient, and the optimal coefficients were found by comparing with the number and area of wildfires in Korea. The existing FFMC used precipitation measured at noon, but in the present invention, daily accumulated precipitation was used to make a daily FFMC. The precipitation reference value was increased by changing the precipitation data from instantaneous precipitation to cumulative precipitation. 10 is a result of comparing the spatial distribution of the existing FFMC and the optimized FFMC (that is, the modified FFMC according to the present invention), and since precipitation determines the degree of drying and is an important variable in FFMC calculation, the FFMC most simulates the pattern of precipitation. I could see that a lot was followed. The FFMC was modified to suit the Korean environment, and the existing FFMC, which was heavily biased in the amount of precipitation, was modified to affect it more gently.
도 11은 기존 FFMC와 최적화된 FFMC를 우리나라 산불 개수와 비교한 결과로서, 기존 FFMC에 비해서 최적화된 FFMC가 시계열을 더 잘 보여주는 것을 알 수 있다(보라색 화살표 참고).11 is a result of comparing the existing FFMC and the optimized FFMC with the number of wildfires in Korea, and it can be seen that the optimized FFMC shows the time series better than the existing FFMC (refer to the purple arrow).
아래의 [표 2]와 같이, 기존 FFMC와 최적화된 FFMC를 각 산불이 발생한 날에 대하여 모든 산불 픽셀과 산불이 일어나지 않은 픽셀의 FFMC 지수를 계산한 후 산불 픽셀들의 CDF(Cumulative Distribution Function) 값을 평균하여 도출한 후 비교하였다. CDF는 어떤 확률 분포에 대해서 확률 변수가 특정 값보다 작거나 같은 확률로, 예를 들어, CDF가 0.95라면 상위 5 %에 해당하는 높은 지수이다. 기존 FFMC와 최적화된 FFMC 값 분포가 다르기 때문에, 이를 비교하기 위하여 각 지수 값을 CDF로 변환하여 정확도를 분석하였다.As shown in [Table 2] below, the CDF (Cumulative Distribution Function) value of the wildfire pixels was calculated after calculating the FFMC index of all wildfire pixels and non-fired pixels for each wildfire day for the existing FFMC and the optimized FFMC. The average was derived and then compared. CDF is the probability that a random variable is less than or equal to a certain value for a certain probability distribution, for example, if the CDF is 0.95, it is a high index corresponding to the top 5%. Since the distribution of the existing FFMC and the optimized FFMC value is different, each index value was converted into a CDF and the accuracy was analyzed for comparison.
산불 면적wildfire area >= 50ha>= 50ha < 50ha< 50 ha < 10ha< 10ha < 1ha< 1 ha
기존existing
FFMCFFMC
FFMC 평균FFMC average 87.024487.0244 86.049486.0494 83.850683.8506 80.975180.9751
CDF 평균CDF average 0.7690.769 0.7910.791 0.5750.575 0.4290.429
최적화된optimized
FFMCFFMC
FFMC 평균FFMC average 60.913560.9135 58.974158.9741 51.859851.8598 49.236749.2367
CDF 평균CDF average 0.9720.972 0.9780.978 0.9600.960 0.9240.924
기존 FFMC에 비하여 최적화된 FFMC의 평균 CDF 값이 0.9 이상의 높은 값으로 나타났으며, 피해 면적이 큰 산불일수록 CDF 평균값이 높은 경향을 보였다. 이를 통해, 최적화된 FFMC가 기존 FFMC보다 우리나라에 더 적합함을 알 수 있다. 우리나라 환경에 맞게 수정된 FFMC를 산불 다발 지역 지도, 가뭄 지수와 융합하여 우리나라 환경에 맞는 산불 위험 지수(Firk Risk Index, FRI)를 개발하였다. 기존의 캐나다 산불 위험 지수(CFWI)의 산출 방식은 아래와 같이 바람과 FFMC에 관한 함수, DMC와 DC에 관한 함수 그리고 계수를 곱하여 생성된다.Compared to the existing FFMC, the average CDF value of the optimized FFMC was higher than 0.9, and the larger the damage area, the higher the average CDF value. Through this, it can be seen that the optimized FFMC is more suitable for Korea than the existing FFMC. The FFMC, modified for the Korean environment, was fused with the map of areas prone to forest fires and the drought index to develop a Fire Risk Index (FRI) suitable for the Korean environment. The existing Canadian Forest Fire Hazard Index (CFWI) calculation method is generated by multiplying a function for wind and FFMC, a function for DMC and DC, and a coefficient as follows.
CFWI = coefficient * f(wind,FFMC) * f(DMC,DC)CFWI = coefficient * f(wind,FFMC) * f(DMC,DC)
따라서, 본 발명에 따른 산불 위험 지수(FRI)는 아래와 같이 수정된 FFMC(revised FFMC), 가뭄 지수(drought idx), 그리고 산불 다발 지역 지도(frequency)를 계수처럼 이용하여 개발되었으며, 계절별 특성을 고려해주기 위하여 월별로 다른 가중치(temporal weight)를 주기 위한 과정이 추가되었다.Therefore, the forest fire risk index (FRI) according to the present invention was developed using the revised FFMC (revised FFMC), drought idx, and forest fire frequent area map (frequency) as coefficients as follows, and considering the seasonal characteristics A process for giving a different weight (temporal weight) for each month has been added.
FRI = (frequency + 0.5) * (revised FFMC) * (1.5 - drought idx) * (temporal weight)FRI = (frequency + 0.5) * (revised FFMC) * (1.5 - drought idx) * (temporal weight)
여기서, 산불 다발 지역 지도(frequency)와 가뭄 지수(drought idx)에 더해지는 상수는 각 지수들이 최소 0의 값을 가지는 경우 곱해주었을 때 FRI가 0이 되는 상황을 방지하기 위한 것으로, 여러 가지 상수들을 CDF 분석, 같은 날의 모든 픽셀 중 상위 몇% 에 속하는지에 대한 분석을 통하여 산불 발생을 가장 잘 모의한다고 판단된 상수를 최종적으로 이용하였다.Here, the constant added to the forest fire frequency and drought idx is to prevent the situation in which FRI becomes 0 when multiplied when each indices has a minimum value of 0. Through analysis and analysis of how many percent of all pixels on the same day belong to, the constant determined to best simulate the occurrence of a forest fire was finally used.
도 12는 본 발명의 바람직한 실시예에 따른 산불 위험 지수의 획득에 이용되는 가뭄 지수를 설명하기 위한 도면이다.12 is a view for explaining a drought index used to obtain a forest fire risk index according to a preferred embodiment of the present invention.
도 12는 앞서 개발된 산불 발생 관련 가뭄 지수들을 산불(Fire)과 비산불(Nonfire) 픽셀들에 대하여 분포를 비교한 것으로, 앞서 개발된 다양한 가뭄 지수가 산불 위험 지수를 개발하는 데에 시험되었으며, 그 중 가장 유의미한 결과를 보여주었던 가뭄 지수들의 분포를 나타내었다. 본 가뭄 지수들을 이용하여 산불 위험 지수를 도출한 이후 CDF 및 상위%를 분석한 결과, 가뭄 지수 중 Scheme 2가 산불 위험 지수 개발에 있어 가장 적합한 것으로 판단되었다. 이에, 본 발명에 따른 산불 위험 지수의 획득에 이용되는 가뭄 지수는 가중치를 적용한 가뭄 지수들 중에서 Scheme 2에 따른 가뭄 지수를 이용하였다.12 is a comparison of the distribution of the previously developed forest fire-related drought indices for wildfire and nonfire pixels, and various previously developed drought indices were tested to develop a forest fire risk index, Among them, the distribution of drought indices that showed the most significant results is shown. After deriving the forest fire risk index using these drought indices, as a result of analyzing the CDF and the top percent, Scheme 2 among the drought indices was judged to be the most suitable for the development of the forest fire risk index. Accordingly, the drought index used to obtain the forest fire risk index according to the present invention was a drought index according to Scheme 2 among drought indices to which a weight was applied.
월별 가중치(temporal weight)를 주는 방법은 2014년부터 2017년까지 발생한 모든 산불에 대하여 월별 발생 건수 비율에 따라 월별 발생 건수가 많을수록 더 큰 FRI 값을 가질 수 있도록 가중치를 주는 방법(FRI_M1)과 월별 산불 발생 건수가 가장 많은 3월 ~ 5월만 가중치를 주는 방법(FRI_M2) 두 가지를 시험하였다.The method of giving the monthly weight (temporal weight) is the method of giving weight so that the larger the number of monthly occurrences, the greater the FRI value (FRI_M1) and the monthly forest fire Two methods were tested (FRI_M2), in which only March to May with the highest number of occurrences were weighted.
FRI에 계절별 특성을 고려하기 위하여 월별 가중치를 곱해준 FRI_M1과 FRI_M2의 적합성을 판단하기 위하여, 기존 FFMC와 수정된 FFMC를 비교하였던 것과 마찬가지로 CDF 분석을 실시하였으며, CDF는 어떤 확률 분포에 대해서 확률 변수가 특정 값보다 작거나 같은 확률을 의미한다. 비교를 위하여 2014년부터 2017년동안 산불이 발생한 날에 대하여 모든 산불 픽셀과 비산불 픽셀의 FFMC와 FRI를 계산한 후, 아래의 [표 3]과 같이 산불 픽셀들의 CDF 값을 평균하여 도출하였다.To determine the suitability of FRI_M1 and FRI_M2, which were multiplied by monthly weights to consider seasonal characteristics, CDF analysis was performed similarly to comparing the existing FFMC and the modified FFMC. A probability that is less than or equal to a certain value. For comparison, the FFMC and FRI of all wildfire pixels and non-wildfire pixels were calculated for the days of wildfires from 2014 to 2017, and then the CDF values of the wildfire pixels were averaged and derived as shown in [Table 3] below.
산불 면적wildfire area >= 50ha>= 50ha < 50ha< 50 ha < 10ha< 10ha < 1ha< 1 ha
기존existing
FFMCFFMC
CDF 평균CDF average 0.7690.769 0.7910.791 0.5750.575 0.4290.429
수정된Modified
FFMCFFMC
CDF 평균CDF average 0.9720.972 0.9780.978 0.9600.960 0.9240.924
FRI_M1FRI_M1 CDF 평균CDF average 0.9450.945 0.9940.994 0.9530.953 0.8950.895
FRI_M2FRI_M2 CDF 평균CDF average 0.9590.959 0.9790.979 0.9740.974 0.9280.928
그 결과 기존 FFMC 보다 눈에 띄게 수치가 향상된 것을 확인할 수 있었으며 수정된 FFMC와 비교했을 때에도 FRI가 수정된 FFMC와 비슷하거나 혹은 더 높은 수치를 보여주고 있으므로 비산불 픽셀보다 산불 픽셀들의 FRI 값이 높은 것으로 해석할 수 있다. 모든 연구 기간이 아닌 산불이 발생한 당일에 한하여 공간적인 모의 정확성을 파악하기 위하여, 각 산불의 FFMC, FRI가 전국의 산불 위험 지수 중 상위 몇% 에 속하는지 분석해 보았다. 그 결과, 아래의 [표 4]와 같이, 기존 FFMC에 비하여 FRI의 상위 5% 내에 속하는 산불의 비율이 약 2배 가까이 증가하였으며, 상위 40% 이내의 산불은 58.55%에서 평균 67.91% 수준으로 증가하였다.As a result, it was confirmed that the value was significantly improved compared to the existing FFMC, and when compared with the modified FFMC, the FRI showed similar or higher values to the modified FFMC, so it was found that the FRI value of the wildfire pixels was higher than that of the non-wildfire pixels. can be interpreted In order to understand the spatial simulation accuracy only on the day of the wildfire, not during the entire study period, the FFMC and FRI of each forest fire were analyzed to be among the top percent of the national forest fire risk index. As a result, as shown in [Table 4] below, compared to the existing FFMC, the proportion of forest fires within the top 5% of FRIs has increased by nearly double, and the forest fires within the top 40% increased from 58.55% to an average of 67.91%. did
상위%difference% <= 5%<= 5% <= 10%<= 10% <= 20%<= 20% <= 30%<= 30% <= 40%<= 40% <= 50%<= 50% > 50%> 50% 총계sum
기존existing
FFMCFFMC
12.13412.134 10.43410.434 14.44814.448 12.18112.181 9.3489.348 8.5938.593 32.86132.861 100100
FRI_M1FRI_M1 20.60820.608 10.16110.161 16.14416.144 11.72811.728 9.4979.497 7.0287.028 24.83424.834 100100
FRI_M2FRI_M2 20.56020.560 10.44610.446 15.90715.907 11.72811.728 9.5449.544 7.0287.028 24.78624.786 100100
도 13은 본 발명의 바람직한 실시예에 따른 산불 위험 지수의 획득에 이용되는 제1 월별 가중치를 설명하기 위한 도면이고, 도 14는 본 발명의 바람직한 실시예에 따른 산불 위험 지수의 획득에 이용되는 제2 월별 가중치를 설명하기 위한 도면이다.도 13과 도 14는 기존의 산림청 산림과학원 산불 위험 예보 시스템에서 제공하고 있는 산불 위험 지수(DWI)를 본 발명에서 제안된 산불 위험 지수 중 월별 산불 발생 건수가 많을수록 FRI가 더 높은 값을 가질 수 있도록 가중치를 준 모델(FRI_M1) 및 산불 발생 건수가 가장 많았던 3월 ~ 5월에 대하여 가중치를 준 모델(FRI_M2)과 2014년부터 2017년까지의 우리나라 산불 개수와 비교한 결과로서, FRI_M1과 FRI_M2 모두 DWI에 비하여 월별 산불 발생 건수의 상승 및 하강 시계열 패턴과 잘 일치하는 부분을 보여주었으며, 특히 FRI_M1의 경우 기존의 산불 위험 지수(DWI)에 비해서 본 발명에 따른 산불 위험 지수(FRI)가 월별 산불 발생 건수가 보여주는 시계열과 더욱 잘 일치하는 것을 알 수 있다(보라색 상자 참고). 이에, 본 발명에 따른 산불 위험 지수의 획득에 이용되는 월별 가중치는 월별 산불 발생 건수가 많을수록 FRI가 더 높은 값을 가질 수 있도록 가중치를 준 제1 월별 가중치를 이용하였다.13 is a view for explaining a first monthly weight used to obtain a forest fire risk index according to a preferred embodiment of the present invention, Figure 14 is a second used to obtain a forest fire risk index according to a preferred embodiment of the present invention 2 It is a diagram for explaining the monthly weight. FIGS. 13 and 14 show the forest fire risk index (DWI) provided by the existing forest fire risk forecasting system of the Forestry Academy of the Korea Forest Service. The model (FRI_M1) weighted so that FRI has a higher value as the number increases, and the model weighted for March to May when the number of wildfires occurred the most (FRI_M2), and the number of wildfires in Korea from 2014 to 2017 As a result of comparison, both FRI_M1 and FRI_M2 showed good agreement with the rising and falling time series patterns in the number of monthly forest fires compared to DWI. It can be seen that the risk index (FRI) is in better agreement with the time series of monthly wildfire occurrences (see purple box). Therefore, as the monthly weight used to obtain the forest fire risk index according to the present invention, the first monthly weight weighted so that the FRI has a higher value as the number of monthly forest fires increases was used.
그러면, 도 15를 참조하여 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 방법에 대하여 설명한다.Then, a method for providing a forest fire risk index according to a preferred embodiment of the present invention will be described with reference to FIG. 15 .
도 15는 본 발명의 바람직한 실시예에 따른 산불 위험 지수 제공 방법을 설명하기 위한 흐름도이다.15 is a flowchart for explaining a method for providing a forest fire risk index according to a preferred embodiment of the present invention.
도 15를 참조하면, 산불 위험 지수 제공 장치(100)는 기계 학습 알고리즘을 기반으로, 1km의 격자 크기로 다운스케일링된 토양 수분 지수를 획득할 수 있다(S110).Referring to FIG. 15 , the apparatus 100 for providing a forest fire risk index may obtain a soil moisture index downscaled to a grid size of 1 km based on a machine learning algorithm ( S110 ).
즉, 산불 위험 지수 제공 장치(100)는 기계 학습 알고리즘을 기반으로, TRMM 강수 자료, ASCAT 토양 수분 자료, NDVI, LST 및 DEM을 입력 변수로 하고, GLDAS 토양 수분 자료를 출력 변수로 하는, 토양 수분 지수 다운스케일링 모델을 생성한다. 여기서, 기계 학습 알고리즘은 랜덤 포레스트(RF), 서포트 벡터 회귀 분석(SVR) 및 인공 신경망(ANN) 중 하나를 이용할 수 있다. 특히, 본 발명은 랜덤 포레스트(RF)를 이용하여 토양 수분 지수 다운스케일링 모델을 생성할 수 있다.That is, the forest fire risk index providing device 100 is based on a machine learning algorithm, with TRMM precipitation data, ASCAT soil moisture data, NDVI, LST, and DEM as input variables, and soil moisture with GLDAS soil moisture data as output variables. Create an exponential downscaling model. Here, the machine learning algorithm may use one of random forest (RF), support vector regression (SVR), and artificial neural network (ANN). In particular, the present invention can generate a soil moisture index downscaling model using a random forest (RF).
이때, 산불 위험 지수 제공 장치(100)는 자료 간 공간 해상도의 통일성을 위해, GLDAS 토양 수분 자료의 격자 크기와 동일한 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여 토양 수분 지수 다운스케일링 모델을 생성한다. 그리고, 산불 위험 지수 제공 장치(100)는 1km의 격자 크기로 변환된 입력 변수를 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 토양 수분 지수를 획득한다.At this time, the forest fire risk index providing device 100 uses, as training data, the upscaling data to a grid size of 25 km, which is the same as the grid size of the GLDAS soil moisture data, as training data for the unity of spatial resolution between the data, and the soil moisture index downscaling model create Then, the forest fire risk index providing apparatus 100 obtains a soil moisture index downscaled to a grid size of 1 km by inputting an input variable converted to a grid size of 1 km into a soil moisture index downscaling model.
보다 자세하게 설명하면, 산불 위험 지수 제공 장치(100)는 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, TRMM 강수 자료, ASCAT 토양 수분 자료, NDVI, LST 및 DEM을 입력 변수로 하고, GLDAS 토양 수분 자료를 출력 변수로 하는, 제1 토양 수분 지수 다운스케일링 모델을 생성할 수 있다. 그리고, 산불 위험 지수 제공 장치(100)는 25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, TRMM 강수 자료, NDVI, LST 및 DEM을 입력 변수로 하고, GLDAS 토양 수분 자료를 출력 변수로 하는, 제2 토양 수분 지수 다운스케일링 모델을 생성할 수 있다. 그런 다음, 산불 위험 지수 제공 장치(100)는 1km의 격자 크기로 변환된 입력 변수를 제1 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 제1 토양 수분 지수를 획득하고, 1km의 격자 크기로 변환된 입력 변수를 제2 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 제2 토양 수분 지수를 획득하며, 제1 토양 수분 지수에서 누락된 부분은 제2 토양 수분 지수로 대체하여 1km의 격자 크기로 다운스케일링된 최종 토양 수분 지수를 획득할 수 있다.More specifically, the forest fire risk index providing device 100 uses the data upscaled to a grid size of 25 km as training data, TRMM precipitation data, ASCAT soil moisture data, NDVI, LST and DEM as input variables, Using the GLDAS soil moisture data as an output variable, a first soil moisture index downscaling model may be generated. And, the forest fire risk index providing device 100 uses the data upscaled to a grid size of 25 km as training data, TRMM precipitation data, NDVI, LST, and DEM as input variables, and GLDAS soil moisture data as output variables. , it is possible to generate a second soil moisture index downscaling model. Then, the forest fire risk index providing device 100 inputs the input variable converted to the grid size of 1 km into the first soil moisture index downscaling model to obtain the first soil moisture index downscaled to the grid size of 1 km, The input variable converted to a grid size of 1 km is input to the second soil moisture index downscaling model to obtain a second soil moisture index downscaled to a grid size of 1 km, and the missing part in the first soil moisture index is the second By substituting the soil moisture index, the final soil moisture index downscaled to a grid size of 1 km can be obtained.
그런 다음, 산불 위험 지수 제공 장치(100)는 1km의 격자 크기로 다운스케일링된 토양 수분 지수, NDWI 및 TCI를 이용하여 가뭄 지수를 획득할 수 있다(S130).Then, the forest fire risk index providing apparatus 100 may obtain a drought index by using the soil moisture index, NDWI, and TCI downscaled to a grid size of 1 km (S130).
즉, 산불 위험 지수 제공 장치(100)는 식 0.4 * (다운스케일링된 토양 수분 지수) + 0.3 * (NDWI) + 0.3 * (TCI)를 통해 가뭄 지수를 획득할 수 있다.That is, the forest fire risk index providing apparatus 100 may obtain the drought index through the equation 0.4 * (downscaled soil moisture index) + 0.3 * (NDWI) + 0.3 * (TCI).
그러면, 산불 위험 지수 제공 장치(100)는 산불 다발 지역 지도, 수정된 FFMC, 가뭄 지수 및 월별 가중치를 이용하여 산불 위험 지수를 획득할 수 있다(S150).Then, the apparatus 100 for providing the forest fire risk index may obtain a forest fire risk index by using the wildfire frequent area map, the modified FFMC, the drought index, and the monthly weight (S150).
즉, 산불 위험 지수 제공 장치(100)는 식 (산불 다발 지역 지도 + 0.5) * (수정된 FFMC) * (1.5 - 가뭄 지수) * (월별 가중치)를 통해 산불 위험 지수를 획득할 수 있다.That is, the apparatus 100 for providing the forest fire risk index may obtain the forest fire risk index through the equation (wildfire frequent area map + 0.5) * (modified FFMC) * (1.5 - drought index) * (monthly weight).
여기서, 월별 가중치는 과거에 발생한 모든 산불을 기반으로 획득한 월별 산불 발생 건수 비율을 이용하여, 월별 산불 발생 건수가 많을수록 더 큰 가중치가 부여될 수 있다.Here, the monthly weight may be given a greater weight as the number of monthly forest fires increases, using the ratio of the number of monthly wildfires obtained based on all forest fires that have occurred in the past.
그리고, 수정된 FFMC는 상대 습도, 정오에 측정한 강수량, 온도, 풍속을 이용하여 계산된 당일의 평형 수분량, 건조율 및 최소 수분량을 기반으로 FFMC를 산출하는 종래의 FFMC에서, 강수 영향 범위을 수정한 FFMC를 말한다. 즉, 수정된 FFMC는 종래의 FFMC에서, FFMC 초기값, 강수량 기준값, FFMC 기준값 및 건조율을 계산하는 식의 계수가 수정되고, 전날 수분량을 계산하는 식의 계수가 수정되며, 최소 수분량을 이용하여 FFMC 값을 계산하는 식의 계수가 수정되고, 정오에 측정한 강수량이 아닌 하루 누적 강수량이 이용되며, 강수량 기준값이 종래의 FFMC보다 커진 FFMC를 말한다.And, the modified FFMC is the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content of the day calculated using the relative humidity, precipitation measured at noon, temperature, and wind speed. say FFMC. That is, in the modified FFMC, the coefficient of the formula for calculating the FFMC initial value, the precipitation reference value, the FFMC reference value and the drying rate is modified in the conventional FFMC, the coefficient of the formula calculating the moisture content of the previous day is modified, and the minimum moisture content is used It refers to an FFMC in which the coefficient of the equation for calculating the FFMC value is modified, the accumulated precipitation per day is used instead of the precipitation measured at noon, and the precipitation reference value is larger than that of the conventional FFMC.
이후, 산불 위험 지수 제공 장치(100)는 획득한 산불 위험 지수를 기반으로, 예보일에 대한 산불 위험 지수 값을 획득(S170).Thereafter, the forest fire risk index providing apparatus 100 obtains a forest fire risk index value for the forecast date based on the acquired wildfire risk index (S170).
이상에서 설명한 본 발명의 실시예를 구성하는 모든 구성요소들이 하나로 결합하거나 결합하여 동작하는 것으로 기재되어 있다고 해서, 본 발명이 반드시 이러한 실시예에 한정되는 것은 아니다. 즉, 본 발명의 목적 범위 안에서라면, 그 모든 구성요소들이 하나 이상으로 선택적으로 결합하여 동작할 수도 있다. 또한, 그 모든 구성요소들이 각각 하나의 독립적인 하드웨어로 구현될 수 있지만, 각 구성요소들의 그 일부 또는 전부가 선택적으로 조합되어 하나 또는 복수개의 하드웨어에서 조합된 일부 또는 전부의 기능을 수행하는 프로그램 모듈을 갖는 컴퓨터 프로그램으로서 구현될 수도 있다. 또한, 이와 같은 컴퓨터 프로그램은 USB 메모리, CD 디스크, 플래쉬 메모리 등과 같은 컴퓨터가 읽을 수 있는 기록 매체(Computer Readable Media)에 저장되어 컴퓨터에 의하여 읽혀지고 실행됨으로써, 본 발명의 실시예를 구현할 수 있다. 컴퓨터 프로그램의 기록 매체로서는 자기기록매체, 광 기록매체 등이 포함될 수 있다.Even though all the components constituting the embodiment of the present invention described above are described as being combined or operated in combination, the present invention is not necessarily limited to this embodiment. That is, within the scope of the object of the present invention, all the components may operate by selectively combining one or more. In addition, all of the components may be implemented as one independent hardware, but a part or all of each component is selectively combined to perform some or all of the functions combined in one or a plurality of hardware program modules It may be implemented as a computer program having In addition, such a computer program is stored in a computer readable media such as a USB memory, a CD disk, a flash memory, etc., read and executed by a computer, thereby implementing the embodiment of the present invention. The recording medium of the computer program may include a magnetic recording medium, an optical recording medium, and the like.
이상의 설명은 본 발명의 기술 사상을 예시적으로 설명한 것에 불과한 것으로서, 본 발명이 속하는 기술 분야에서 통상의 지식을 가진 자라면 본 발명의 본질적인 특성에서 벗어나지 않는 범위 내에서 다양한 수정, 변경 및 치환이 가능할 것이다. 따라서, 본 발명에 개시된 실시예 및 첨부된 도면들은 본 발명의 기술 사상을 한정하기 위한 것이 아니라 설명하기 위한 것이고, 이러한 실시예 및 첨부된 도면에 의하여 본 발명의 기술 사상의 범위가 한정되는 것은 아니다. 본 발명의 보호 범위는 아래의 청구범위에 의하여 해석되어야 하며, 그와 동등한 범위 내에 있는 모든 기술 사상은 본 발명의 권리범위에 포함되는 것으로 해석되어야 할 것이다.The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains may make various modifications, changes and substitutions within the scope without departing from the essential characteristics of the present invention. will be. Accordingly, the embodiments disclosed in the present invention and the accompanying drawings are for explaining, not limiting, the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments and the accompanying drawings . The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.
< 부호의 설명 >< Explanation of symbols >
100 : 산불 위험 지수 제공 장치,100: forest fire risk index providing device;
110 : 토양 수분 지수 획득부,110: soil moisture index acquisition unit,
130 : 가뭄 지수 획득부,130: drought index acquisition unit,
150 : 산불 위험 지수 획득부,150: forest fire risk index acquisition unit,
170 : 예보부170: forecast department

Claims (13)

  1. 산불 다발 지역 지도, 수정된 FFMC(Fine Fuel Moisture Code), 가뭄 지수 및 월별 가중치를 이용하여 산불 위험 지수를 획득하는 산불 위험 지수 획득부; 및a forest fire risk index acquisition unit that acquires a forest fire risk index using a map of a wildfire-prone area, a revised Fine Fuel Moisture Code (FFMC), a drought index, and a monthly weight; and
    상기 산불 위험 지수 획득부를 통해 획득한 상기 산불 위험 지수를 기반으로, 예보일에 대한 산불 위험 지수 값을 획득하는 예보부;a forecasting unit for obtaining a forest fire risk index value for a forecast date based on the forest fire risk index obtained through the forest fire risk index obtaining unit;
    를 포함하며,includes,
    상기 월별 가중치는, 과거에 발생한 모든 산불을 기반으로 획득한 월별 산불 발생 건수 비율을 이용하여, 월별 산불 발생 건수가 많을수록 더 큰 가중치가 부여되는,The monthly weight, using the ratio of the number of monthly wildfires obtained based on all forest fires that have occurred in the past, is given a greater weight as the number of monthly forest fires increases,
    산불 위험 지수 제공 장치.A device that provides a wildfire risk index.
  2. 제1항에서,In claim 1,
    상기 산불 위험 지수 획득부는,The forest fire risk index acquisition unit,
    식 (상기 산불 다발 지역 지도 + 0.5) * (상기 수정된 FFMC) * (1.5 - 상기 가뭄 지수) * (상기 월별 가중치)를 통해 상기 산불 위험 지수를 획득하는,Obtaining the forest fire risk index through the formula (the wildfire hot zone map + 0.5) * (the modified FFMC) * (1.5 - the drought index) * (the monthly weight),
    산불 위험 지수 제공 장치.A device that provides a wildfire risk index.
  3. 제1항에서,In claim 1,
    상기 수정된 FFMC는,The modified FFMC is,
    상대 습도, 정오에 측정한 강수량, 온도, 풍속을 이용하여 계산된 당일의 평형 수분량, 건조율 및 최소 수분량을 기반으로 FFMC를 산출하는 종래의 FFMC에서, FFMC 초기값, 강수량 기준값, FFMC 기준값 및 건조율을 계산하는 식의 계수가 수정되고, 전날 수분량을 계산하는 식의 계수가 수정되며, 최소 수분량을 이용하여 FFMC 값을 계산하는 식의 계수가 수정되고, 정오에 측정한 강수량이 아닌 하루 누적 강수량이 이용되며, 강수량 기준값이 종래의 FFMC보다 커진,In the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content for the day calculated using relative humidity, precipitation measured at noon, temperature, and wind speed, FFMC initial value, precipitation reference value, FFMC reference value and dry The coefficient of the equation for calculating the tuning is corrected, the coefficient of the equation for calculating the moisture content of the previous day is corrected, the coefficient of the equation for calculating the FFMC value using the minimum moisture content is corrected, and the cumulative precipitation per day, not the precipitation measured at noon is used, and the precipitation reference value is larger than that of the conventional FFMC,
    산불 위험 지수 제공 장치.A device that provides a wildfire risk index.
  4. 제1항에서,In claim 1,
    1km의 격자 크기로 다운스케일링된 토양 수분 지수, NDWI(Normalized Different Water Index) 및 TCI(Temperature Condition Index)를 이용하여 상기 가뭄 지수를 획득하는 가뭄 지수 획득부;a drought index acquisition unit configured to acquire the drought index using a soil moisture index downscaled to a grid size of 1 km, a Normalized Different Water Index (NDWI), and a Temperature Condition Index (TCI);
    를 더 포함하는 산불 위험 지수 제공 장치.A device for providing a forest fire risk index further comprising a.
  5. 제4항에서,In claim 4,
    상기 가뭄 지수 획득부는,The drought index acquisition unit,
    식 0.4 * (상기 다운스케일링된 토양 수분 지수) + 0.3 * (상기 NDWI) + 0.3 * (상기 TCI)을 통해 상기 가뭄 지수를 획득하는,Obtaining the drought index through the formula 0.4 * (the downscaled soil moisture index) + 0.3 * (the NDWI) + 0.3 * (the TCI),
    산불 위험 지수 제공 장치.A device that provides a wildfire risk index.
  6. 제4항에서,In claim 4,
    25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, 기계 학습 알고리즘을 기반으로, TRMM(Tropical Rainfall Measuring Mission) 강수 자료, ASCAT(Advanced SCATterometter) 토양 수분 자료, NDVI(Normalised Difference Vegetation Index), LST(Land Surface Temperature) 및 DEM(digital Elevation Model)을 입력 변수로 하고, GLDAS(Global Land Data Assimilation System) 토양 수분 자료를 출력 변수로 하는, 토양 수분 지수 다운스케일링 모델을 생성하고, 1km의 격자 크기로 변환된 상기 입력 변수를 상기 토양 수분 지수 다운스케일링 모델에 입력하여 상기 다운스케일링된 토양 수분 지수를 획득하는 토양 수분 지수 획득부;Using the data upscaled to a grid size of 25 km as training data, based on a machine learning algorithm, TRMM (Tropical Rainfall Measuring Mission) precipitation data, ASCAT (Advanced SCATterometter) soil moisture data, NDVI (Normalized Difference Vegetation Index), A Soil Moisture Index downscaling model is created using Land Surface Temperature (LST) and Digital Elevation Model (DEM) as input variables and Global Land Data Assimilation System (GLDAS) soil moisture data as output variables, and a grid size of 1 km a soil moisture index acquisition unit configured to obtain the downscaled soil moisture index by inputting the input variable converted to , into the soil moisture index downscaling model;
    를 더 포함하는 산불 위험 지수 제공 장치.A device for providing a forest fire risk index further comprising a.
  7. 제6항에서,In claim 6,
    상기 토양 수분 지수 획득부는,The soil moisture index acquisition unit,
    25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, 상기 TRMM 강수 자료, 상기 ASCAT 토양 수분 자료, 상기 NDVI, 상기 LST 및 상기 DEM을 입력 변수로 하고, 상기 GLDAS 토양 수분 자료를 출력 변수로 하는, 제1 토양 수분 지수 다운스케일링 모델을 생성하고,Using the data upscaled to a grid size of 25 km as training data, the TRMM precipitation data, the ASCAT soil moisture data, the NDVI, the LST, and the DEM are input variables, and the GLDAS soil moisture data are output variables. to create a first soil moisture index downscaling model,
    25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, 상기 TRMM 강수 자료, 상기 NDVI, 상기 LST 및 상기 DEM을 입력 변수로 하고, 상기 GLDAS 토양 수분 자료를 출력 변수로 하는, 제2 토양 수분 지수 다운스케일링 모델을 생성하며,Using the data upscaled to a grid size of 25 km as training data, the TRMM precipitation data, the NDVI, the LST, and the DEM are input variables, and the GLDAS soil moisture data are output variables, second soil moisture create an exponential downscaling model,
    1km의 격자 크기로 변환된 입력 변수를 상기 제1 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 제1 토양 수분 지수를 획득하고, 1km의 격자 크기로 변환된 입력 변수를 상기 제2 토양 수분 지수 다운스케일링 모델에 입력하여 1km의 격자 크기로 다운스케일링된 제2 토양 수분 지수를 획득하며, 제1 토양 수분 지수에서 누락된 부분은 상기 제2 토양 수분 지수로 대체하여 상기 다운스케일링된 토양 수분 지수를 획득하는,The input variable converted to a grid size of 1 km is input to the first soil moisture index downscaling model to obtain a first soil moisture index downscaled to a grid size of 1 km, and the input variable converted to a grid size of 1 km is the input variable. A second soil moisture index downscaled to a grid size of 1 km is obtained by inputting the second soil moisture index downscaling model, and the missing part in the first soil moisture index is replaced with the second soil moisture index to perform the downscaling. to obtain the soil moisture index,
    산불 위험 지수 제공 장치.A device that provides a wildfire risk index.
  8. 산불 위험 지수 제공 장치에 의해 수행되는 산불 위험 지수 제공 방법으로서,A method for providing a forest fire risk index performed by a device for providing a forest fire risk index, comprising:
    산불 다발 지역 지도, 수정된 FFMC(Fine Fuel Moisture Code), 가뭄 지수 및 월별 가중치를 이용하여 산불 위험 지수를 획득하는 단계; 및obtaining a forest fire risk index using a forest fire-prone area map, a revised Fine Fuel Moisture Code (FFMC), a drought index, and a monthly weight; and
    상기 산불 위험 지수를 기반으로, 예보일에 대한 산불 위험 지수 값을 획득하는 단계;obtaining a forest fire risk index value for a forecast date based on the forest fire risk index;
    를 포함하며,includes,
    상기 월별 가중치는, 과거에 발생한 모든 산불을 기반으로 획득한 월별 산불 발생 건수 비율을 이용하여, 월별 산불 발생 건수가 많을수록 더 큰 가중치가 부여되는,The monthly weight, using the ratio of the number of monthly wildfires obtained based on all forest fires that have occurred in the past, is given a greater weight as the number of monthly forest fires increases,
    를 포함하는 산불 위험 지수 제공 방법.A method of providing a wildfire risk index, including
  9. 제8항에서,In claim 8,
    상기 산불 위험 지수 획득 단계는,The forest fire risk index acquisition step is,
    식 (상기 산불 다발 지역 지도 + 0.5) * (상기 수정된 FFMC) * (1.5 - 상기 가뭄 지수) * (상기 월별 가중치)를 통해 상기 산불 위험 지수를 획득하는 것으로 이루어지는,Consists of obtaining the forest fire risk index through the formula (the wildfire hot zone map + 0.5) * (the modified FFMC) * (1.5 - the drought index) * (the monthly weight),
    산불 위험 지수 제공 방법.How to provide a wildfire risk index.
  10. 제8항에서,In claim 8,
    상기 수정된 FFMC는,The modified FFMC is,
    상대 습도, 정오에 측정한 강수량, 온도, 풍속을 이용하여 계산된 당일의 평형 수분량, 건조율 및 최소 수분량을 기반으로 FFMC를 산출하는 종래의 FFMC에서, FFMC 초기값, 강수량 기준값, FFMC 기준값 및 건조율을 계산하는 식의 계수가 수정되고, 전날 수분량을 계산하는 식의 계수가 수정되며, 최소 수분량을 이용하여 FFMC 값을 계산하는 식의 계수가 수정되고, 정오에 측정한 강수량이 아닌 하루 누적 강수량이 이용되며, 강수량 기준값이 종래의 FFMC보다 커진,In the conventional FFMC that calculates the FFMC based on the equilibrium moisture content, drying rate and minimum moisture content for the day calculated using relative humidity, precipitation measured at noon, temperature, and wind speed, FFMC initial value, precipitation reference value, FFMC reference value and dry The coefficient of the equation for calculating the tuning is corrected, the coefficient of the equation for calculating the moisture content of the previous day is corrected, the coefficient of the equation for calculating the FFMC value using the minimum moisture content is corrected, and the cumulative precipitation per day, not the precipitation measured at noon is used, and the precipitation reference value is larger than that of the conventional FFMC,
    산불 위험 지수 제공 방법.How to provide a wildfire risk index.
  11. 제8항에서,In claim 8,
    1km의 격자 크기로 다운스케일링된 토양 수분 지수, NDWI(Normalized Different Water Index) 및 TCI(Temperature Condition Index)를 이용하여 상기 가뭄 지수를 획득하는 단계;obtaining the drought index using a soil moisture index downscaled to a grid size of 1 km, a Normalized Different Water Index (NDWI), and a Temperature Condition Index (TCI);
    를 더 포함하는 산불 위험 지수 제공 방법.A method of providing a forest fire risk index further comprising:
  12. 제11항에서,In claim 11,
    25km의 격자 크기로 업스케일링한 자료를 훈련 데이터로 이용하여, 기계 학습 알고리즘을 기반으로, TRMM(Tropical Rainfall Measuring Mission) 강수 자료, ASCAT(Advanced SCATterometter) 토양 수분 자료, NDVI(Normalised Difference Vegetation Index), LST(Land Surface Temperature) 및 DEM(digital Elevation Model)을 입력 변수로 하고, GLDAS(Global Land Data Assimilation System) 토양 수분 자료를 출력 변수로 하는, 토양 수분 지수 다운스케일링 모델을 생성하고, 1km의 격자 크기로 변환된 상기 입력 변수를 상기 토양 수분 지수 다운스케일링 모델에 입력하여 상기 다운스케일링된 토양 수분 지수를 획득하는 단계;Using the data upscaled to a grid size of 25 km as training data, based on a machine learning algorithm, TRMM (Tropical Rainfall Measuring Mission) precipitation data, ASCAT (Advanced SCATterometter) soil moisture data, NDVI (Normalized Difference Vegetation Index), A Soil Moisture Index downscaling model is created using Land Surface Temperature (LST) and Digital Elevation Model (DEM) as input variables and Global Land Data Assimilation System (GLDAS) soil moisture data as output variables, and a grid size of 1 km obtaining the downscaled soil moisture index by inputting the input variable converted to , into the soil moisture index downscaling model;
    를 더 포함하는 산불 위험 지수 제공 방법.A method of providing a forest fire risk index further comprising:
  13. 제8항 내지 제12항 중 어느 한 항에 기재된 산불 위험 지수 제공 방법을 컴퓨터에서 실행시키기 위하여 컴퓨터로 읽을 수 있는 기록 매체에 저장된 컴퓨터 프로그램.A computer program stored in a computer-readable recording medium in order to execute the method for providing a forest fire risk index according to any one of claims 8 to 12 on a computer.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117152893A (en) * 2023-10-31 2023-12-01 广州市林业和园林科学研究院 Forest disaster prevention method and system
CN117422313A (en) * 2023-12-18 2024-01-19 中科星图智慧科技安徽有限公司 Method for predicting forest fire risk level by combining meteorological factors and soil factors
CN117516627A (en) * 2023-11-10 2024-02-06 鄄城县自然资源和规划局 Regional vegetation state monitoring system based on unmanned aerial vehicle data

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102532738B1 (en) * 2022-06-20 2023-05-17 메이사플래닛 주식회사 Apparatus and method for detecting a possibility of wildfire

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140027131A1 (en) * 2012-07-24 2014-01-30 The Boeing Company Wildfire arrest and prevention system
KR20150066052A (en) * 2013-12-06 2015-06-16 대한민국(산림청 국립산림과학원장) Method for forecasting big forest fire danger and the system
WO2019200743A1 (en) * 2018-04-17 2019-10-24 平安科技(深圳)有限公司 Forest fire prediction method, apparatus, computer device, and storage medium

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102108752B1 (en) * 2018-05-11 2020-05-28 대한민국 Method for realtime forest fire danger rating forecasting in north korea

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140027131A1 (en) * 2012-07-24 2014-01-30 The Boeing Company Wildfire arrest and prevention system
KR20150066052A (en) * 2013-12-06 2015-06-16 대한민국(산림청 국립산림과학원장) Method for forecasting big forest fire danger and the system
WO2019200743A1 (en) * 2018-04-17 2019-10-24 平安科技(深圳)有限公司 Forest fire prediction method, apparatus, computer device, and storage medium

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
KANG YOO-JIN, SU-MIN PARK, EUN-NA JANG, JUNG-HO IM, CHUN-GEUN KWON, SUK-JUN LEE: "Spatio-temporal enhancement of forest fire risk index using weather forecast and satellite data in South Korea", JOURNAL OF THE KOREAN ASSOCIATION OF GEOGRAPHIC INFORMATION STUDIES, vol. 22, no. 4, 31 December 2019 (2019-12-31), pages 116 - 130, XP055922792, ISSN: 1226-9719, DOI: 10.11108/kagis.2019.22.4.116 *
PARK SUMIN, BOKYUNG SON, JUNGHO IM: "Development of Satellite-based Drought Indices for Assessing Wildfire Risk ", KOREAN JOURNAL OF REMOTE SENSING, vol. 35, no. 6, 31 December 2019 (2019-12-31), pages 1285 - 1298, XP055922796, ISSN: 1225-6161, DOI: 10.7780/kjrs.2019.35.6.3.11 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117152893A (en) * 2023-10-31 2023-12-01 广州市林业和园林科学研究院 Forest disaster prevention method and system
CN117152893B (en) * 2023-10-31 2023-12-29 广州市林业和园林科学研究院 Forest disaster prevention method and system
CN117516627A (en) * 2023-11-10 2024-02-06 鄄城县自然资源和规划局 Regional vegetation state monitoring system based on unmanned aerial vehicle data
CN117516627B (en) * 2023-11-10 2024-05-07 鄄城县自然资源和规划局 Regional vegetation state monitoring system based on unmanned aerial vehicle data
CN117422313A (en) * 2023-12-18 2024-01-19 中科星图智慧科技安徽有限公司 Method for predicting forest fire risk level by combining meteorological factors and soil factors
CN117422313B (en) * 2023-12-18 2024-04-19 中科星图智慧科技安徽有限公司 Method for predicting forest fire risk level by combining meteorological factors and soil factors

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