CN101344937A - Water traffic risk evaluation and prediction method based on geographic information system - Google Patents

Abstract

The invention relates to a method for assessing and forecasting marine traffic risk on the basis of the geographic information system; the method comprises the steps of: taking the present and future situations of navigation risk in a certain water area as a research object, analyzing the features of navigation environment in the water area according to the past and present traffic situation of the water area, establishing a model for assessing and forecasting the risk of collision and stranding accidents by combining the features of marine traffic accidents in the water area, and assessing the influence of the change of navigation conditions in the water area on the navigation environment in the water area, as well as the corresponding navigation risks, thereby visually manifesting the geographic distribution of the risks in the water area and carrying out the dynamic forecasting of the marine traffic risk in the water area in future. The method avoids the simplification in assessments only by using qualitative evaluation and has the features of gridding and dynamic development. The application of the method can not only visually reflect the geographic distribution of the marine traffic risks, but also forecast the situation of navigation environment risks in future.

Description

Waterborne traffic risk assessment and Forecasting Methodology based on Geographic Information System

Technical field

The invention belongs to the Traffic Information Engineering ﹠ Control technical field, is a kind of waterborne traffic risk assessment and Forecasting Methodology based on Geographic Information System specifically.

Background technology

Along with the development of boats and ships maximization and the maneuverability variation that causes thus, ever-increasing volume of vessel traffic, the transportation of dangerous cargo and to the potential threat of marine environment, the management of vessel traffic have become in the world each harbour water area and have extensively adopted and reduce one of effective measures of waterborne traffic risk.

The classic method of handling risk on the sea-freight circle is the reply of passivity: just take measures after accident generation or problem appearance.The very important point is exactly for the decision maker: recognize the limited of resource thereby will anatomize the relevant risk of problem rather than take a certain measure rashly, otherwise bring lower effect with very high cost often.In order to reduce the waterborne traffic risk to greatest extent, should take the initiative method-decision in the face of risk of reply (proactive) of decision maker.USCG (USCG) is defined as " decision in the face of risk ": the information of one or more aftermaths is organically organized and produced a recapitulative orderly system aid decision making person and formulate more rational control measures.The distinguishing feature that decision in the face of risk is different from the tradition decision-making is exactly a possibility of having considered one or more aftermath.

Because the resource-constrained that improves navigation safety at sea, traffic efficiency and protect the marine environment, the necessity that decision in the face of risk is formulated for maritime policy, rules is conspicuous.If these Limited resources can not be by reasonable distribution, such as with the low-risk problem of expensive solution, then high risk problem will be deficient in resources and deal with.The application of decision in the face of risk will address this problem; it is by the venture analysis of science; the risk information that forms a series of architectures and logicality is for decision maker's reference, also reduces the perils of the sea, protects the marine environment to greatest extent and improve traffic efficiency strong decision tool is provided for effective and reasonable distribution limited resources simultaneously.

Navigation environment waterborne is a system that is formed by multiple factor interaction.System safety engineering is the nearest new branch of science that developed rapidly in 50 years, and it is the subject of a door systemization, is to stride knowledge class, synthetic engineering interdisciplinary.It is in the ascendant aspect the research of boats and ships transportation safety.The method of safety system engineering research safety problem mainly is: the theory of applied science knowledge, systems engineering and method are gone to differentiate, are predicted, the various phenomenons of existing unsafe factor and contingent accident in elimination or the control system, thereby the accident that system is taken place under the constraint of factors such as certain loss, efficient is minimized, and promptly reaches the best safety volt attitude under this condition.Risk assessment is that the risk status of system is carried out quantitatively or qualitatively estimating and evaluating.Its basic goal is whether judgement system reaches the Security Target of regulation or do not meet safety requirements, and according to evaluation result, system is adjusted take that some is perfect, steps up security.

At present, Evaluation of Traffic Safety field Japan occupies an leading position on the water.Great bright to have proposed with behaviour's ship difficulty be the navigation environment risk evaluating method of index as holt, boats and ships grasped the ship characteristic change the behaviour's ship degree of difficulty that the influence of behaviour's ship ability is come the whole marine site of quantitative evaluation with the condition of ship type, captain, the depth of water and wind; New well health husband has proposed the influence that quantizes to the natural environmental elements of behaviour's ship ability, and the subjectivity of having verified these indexs and behaviour's ship person is grasped the relation of ship sensation, be of the influence of each key element of objective judgement, and take some countermeasures and improve navigation environment foundation is provided navigation peace gold; Aboveground glad three from two aspect quantitative Treatment the potential risk factor in certain waters, the one, how many ship's navigations has with chance that its ship can be met during this waters, the 2nd, can meet to behaviour ship person to have increased how many burdens at every turn, and with this as the index of the ship's navigation potential danger level under this navigation environment of quantificational expression etc.

Domestic navigation environmental safety assessment waterborne is from the angle of selecting for use to mathematical method, roughly can be divided into two classes at present: a class is to use mathematical methods such as theory of probability and mathematical statistics to set up precise math model, and this method is adopted in the navigation safety evaluation work of inland waters at present basically; Another kind of method is under the incomplete situation of system information, when being difficult to set up precise math model, adopts the method for fuzzy mathematics or gray system theory that system is carried out A+E.Just utilize fuzzy mathematics theory that the assessment of the navigational hazard degree of Water of Xiamen Port has been carried out inquiring into research as Chinese scholar professor Wu Zhaolin.But above evaluation method all is from integral body, can not can not carry out performance prediction to this waters specific to a certain specific region.Below just respectively said method is carried out the generality analysis.

(1) safety index evaluation assessment

General statistical study promptly counts waterborne traffic accident number of packages or the weighting accident conversion number of packages (giving weight coefficient as the grade by accident) that a variety of causes causes, and asks for the number percent that accident that a variety of causes causes accounts for the total number of packages of accident.Mathematical Statistics Analysis is promptly carried out regretional analysis, principal component analysis and correlation analysis etc. to the accident that a variety of causes causes.About the danger level problem of China navigable internal waterways in use, many scholars and maritime affairs administrative authority are that calculate on the basis with the number of packages of the actual accident that takes place in this waters all at present.When using mathematical statistic method that system is carried out assay, require to have certain sample size, along with the increase of sample statistic and when reaching some, frequency distribution just presents stability, and its model and evaluation result are just more reliable.Though said method has been brought into play vital role in the traffic hazard quantitative test work on the water, but also there is certain limitation: at first, the statistics a variety of causes causes the number of packages of accident can only represent the how much absolute of numerical value, does not reflect the degree of contact that all kinds of reasons and accident take place well; Secondly, the sample size that the Mathematical Statistics Analysis method requires is big, and requires that sample distribution is preferably arranged, and it is bigger that the casualty data that has accumulated in real work will satisfy the above-mentioned requirements difficulty.In addition, for the variation of the danger level of predicting the environmental change institute association of opening the navigation or air flight in the future, adopt this method also to be difficult to achieve the goal.

(2) gray system theory

Since first piece of gray system paper " control problem of gray system " that nineteen eighty-two Chinese scholar professor Deng Julong delivers, gray system theory receives domestic and international academia and numerous working peoples' very big concern.In control theory, complete clear and definite system is called white system with information, and the system of information the unknown is called darky system, and partial information is clear and definite, and the indefinite system of partial information is called gray system." INFORMATION OF INCOMPLETE " is the basic meaning of " ash ", and from different occasions, different angles are seen, the implication of " ash " can also be amplified, and gray system theory has proposed a kind of new systematic analytic method, i.e. association analysis method.It is the similar or different degree according to developing state between the factor, the method for coming correlation degree between the measurement factor.Because association analysis is to perform an analysis by development trend, therefore, do not need the typical distribution rule to the undue requirement that how much do not have of sample size yet, calculated amount is little, even the situation of ten variablees (sequence) also can hand computation; And unlikely quantized result and the inconsistent situation of qualitative analysis that the degree of association occurs.Gray system theory is general, and what solve is that system information is familiar with incomplete system, and it can be by carrying out more deep analysis and research to understanding systematicly less information to system.Because the navigation environmental system is the complicated system that is made of multifactor, at present also not fully aware of to the mutual relationship effect between each key element of system, the small probability and the data that add the waterborne traffic accident in addition are difficult to reasons such as collection, cause them both not have simple physics prototype and mathematics prototype, its internal mechanism relation also is a fuzzy uncertain.They all meet the notion of gray system at aspects such as cross correlation effect, degree and data aggregations.Therefore gray system theory is being adopted by many scholars aspect the risk factor analysis of navigation environment.But gray system theory also is not ripe theoretical system, also has many incomplete places.For example, practical problems is used gray theory, adopt different nondimensionalization methods, the conclusion difference, this just is difficult to the convincing conclusion that draws with correlation analysis.In addition, the degree of association can only embody the positive correlation of data rows, can not embody negative correlativing relation, so can not replace related coefficient with the degree of association, the factor analysis method in can not replacing adding up with association analysis method.To some practical problems, also must adopt various statistical analysis techniques such as regretional analysis, principal component analysis (PCA), orthogonal design.

(3) fuzzy mathematics

Fuzzy mathematics is nineteen sixty-five to add the control expert L A. of Ni Fuliya university bundle moral by the U.S. at first to propose.This subject has obtained development rapidly over 40 years.China introduces and studies this subject twenties years only, but because fuzzy mathematics has stronger vitality and seepage force, so development is very rapid.Fuzzy mathematics is the mathematics that has " ambiguity " phenomenon with mathematical method research and processing.The basic skills of fuzzy mathematics evaluation is to select the several factors that will consider from the things of being passed judgment on, take all factors into consideration this things and set up assessment indicator system about the influence of each factor, determine the evaluation criterion of each index factor according to the needs of actual evaluation, determine the subordinate function of each index factor and carry out single factor evaluation.According to the different weights of each factor, use the method and the corresponding principle of subsidiarity of blurring mapping principle, fuzzy diagnosis then, set up the mathematical model of comprehensive evaluation, mathematical model realizes the comprehensive evaluation work to research object according to this.The risk assessment study in the waters of coastal port navigation at present adopts the mode of fuzzy mathematics more, but several evaluation methods of more than referring to all are from integral body, can not be specific to a certain specific region, can't intuitively embody the regional risk difference of certain specific bodies of water, can not carry out performance prediction this waters traffic risk.

Summary of the invention

The objective of the invention is mode, on the basis of enriching full and accurate navigation environmental history data waterborne, set up mathematical model, and a kind of navigation environment gridding based on Geographic Information System, the risk assessment and the Forecasting Methodology of mobilism are provided based on fuzzy mathematics.

To achieve these goals, the method applied in the present invention is: present situation and future with a certain waters navigation risk are research object, according to this waters history and current traffic, analyze the feature of the navigation environment in waters, in conjunction with this waters waterborne traffic accident characteristic, set up collision, grounding accident risk assessment and forecast model, estimate influence and accordingly the open the navigation or air flight risk of the variation of waters navigation condition to the generation of waters navigation environment, embody the geographic distribution of waters risk intuitively, and the waterborne traffic risk in future is carried out performance prediction.

The present invention has avoided those superficialization of only estimating with quilitative method to a certain extent, has the characteristics of gridding, mobilism.Application of the present invention not only can reflect the geographic distribution of waterborne traffic risk intuitively, and can predict following navigation environmental risk situation, make maritime affairs competent authority, pilot and related management department can get information about the risk situation of zones of different, realize the rationalization of resources allocation.Simultaneously to ensureing that the harbour water area has good navigation environment and navigation order, to ensureing that safety of traffic on water has very strong realistic meaning and directive significance.

Description of drawings

Fig. 1 is embodiment of the invention visibility and collision accident match graph of a relation.

Fig. 2 is embodiment of the invention wind-force and collision accident match graph of a relation.

Fig. 3 is venture analysis of embodiment of the invention ship collision and prediction flow process.

Fig. 4 is Calculation of Ship Grounding's risk assessment of embodiment of the invention waters and prediction flow process.

Embodiment

The present invention is described in further detail below in conjunction with drawings and Examples.

The present invention is by to PORT OF TIANJIN waterborne traffic accident and vessel traffic historical data are carried out statistics and analysis at length in recent years, determine waters, PORT OF TIANJIN traffic hazard characterization factor, proposed risk evaluating method, the geographic distribution of waters, PORT OF TIANJIN ship collision and stranded risk has been studied based on grid cell.Concrete implementation step is as follows:

Set up ship collision risk assessment and forecast model:

First step: utilize traffic study, history data collection and expert to ask method such as visit in the research waters and obtain Ship Types distributions in research waters, yardstick distribution, velocity distribution, meeting distance (different Ship's Dimension), the volume of traffic distributions, traffic flow Density Distribution, channel span, understand data and data such as chance angle, geography information, local safety of traffic on water regulation;

Second step: geography information and navigation channel situation in conjunction with the research waters use MapinfoProfessional software that the gridding processing is carried out in the waters.With regard to each cell volume of vessel traffic distribution, yardstick distribution, velocity distribution, traffic flow Density Distribution, meeting chance angle etc. are carried out refinement;

Third step: the relation of the factor such as research waters visibility, wind-force and Ship's Dimension and Collision Accidents of Ships is determined by methods such as data fittings;

Wherein:

A, set up collision accident and visibility relation:

Visibility and collision accident information (seeing Table-1) that investigation is obtained

Table-1 PORT OF TIANJIN waters collision accident and visibility relation table

Above-mentioned data are carried out the match (see figure 1)

General?model?Exp1：f(x)＝a□exp(b□x)

Coefficients(with?95％confidence?bounds)：

a＝10.62 b＝-0.8904

f(v)＝10.62□exp(-0.8904□v)

The result: match is good;

SSE (error of fitting quadratic sum): 0.1847;

R-square (coefficient of multiple determination): 0.9958;

Adjusted R-square (the coefficient of determination): 0.9936 through adjusting;

RMSE (root-mean-square error): 0.3039

Therefore, ship collision visibility factor in waters, PORT OF TIANJIN is:

In the formula: the ship collision visibility factor of waters, V-PORT OF TIANJIN;

V-visibility (in the sea);

V _wWaters ,-PORT OF TIANJIN ship collision visibility weight.

B, set up the relation of collision accident and wind:

Investigate wind and the collision accident relevant information of obtaining (seeing Table-2) in the PORT OF TIANJIN.

Table 2 PORT OF TIANJIN waters collision accident and wind-force relation table

Above-mentioned data are carried out the match (see figure 2), and the result is as follows:

General?model?Exp1：f(x)＝a□exp(b□x)

Coefficients(with?95％confidence?bounds)：

a＝0.1118 b＝0.7451

f(w)＝0.1118□exp(0.7451□w)

The result: match is good;

SSE (error of fitting quadratic sum): 12.08;

R-square (coefficient of multiple determination): 0.9913;

Adjusted R-square (the coefficient of determination): 0.9891 through adjusting;

RMSE (root-mean-square error): 1.738

Therefore, waters, the PORT OF TIANJIN ship collision wind effect factor is:

In the formula: the ship collision wind effect factor of waters, W-PORT OF TIANJIN;

W-wind-force (level);

W _wWaters ,-PORT OF TIANJIN ship collision wind effect weight.

C, set up collision accident and Ship's Dimension relation:

Investigate Ship's Dimension and the collision accident relevant information of obtaining (seeing Table-3) in the PORT OF TIANJIN.

Table 3 PORT OF TIANJIN waters collision accident and Ship's Dimension relation table

Owing to can't carry out good match to above-mentioned data, waters, PORT OF TIANJIN ship collision/scale affects factor expression is:

T _j＝(0.297t _j1+0.102t _j2+0.237t _j3+0.363t _j4)×T _w

In the formula: T _j: waters, the j cell PORT OF TIANJIN ship collision/scale affects factor;

t _J1: 0～5000 ton of boats and ships proportion of j cell;

t _J2: 5000～10000 tons of boats and ships proportions of j cell;

t _J3: 10000～20000 tons of boats and ships proportions of j cell;

t _J4: the j cell is the boats and ships proportion more than 20000 tons;

T _w: the Ship's Dimension weight;

The 4th step: waters ,～PORT OF TIANJIN in 2005 in 2003 transport information that investigation is collected is handled the encounter rate that calculates each cell, and calculate waters ,～PORT OF TIANJIN in 2005 in 2003 ship collision frequency according to factors such as waters, PORT OF TIANJIN visibility, wind-force and Ship's Dimensions.Use Mapinfo Professional software that the geographic distribution of risk of collision is shown then;

The 5th step: use the collision accident geographic distribution of 2003～2005 years PORT OF TIANJIN reality that model is verified, the 3rd jetty is very big to waters concentration of vessel between the East Turkistan dike, and by more from the berth boats and ships, very easily form Meeting Situation, so this section waters accident generation number is maximum with the main channel boats and ships; More from the waters port berth between first jetty to the, three jettys, the boats and ships number of turnover is also more, also is the accident-prone area.

Through contrast, consistent result that model has reflected and actual accidents distributes proves that this model is scientific and reasonable, can be used to predict the PORT OF TIANJIN ship collision risk with the year two thousand twenty in 2010.

The 6th step: the simulation result of the comprehensive port of utilization ship collision forecast model analyzing and processing boat analogue system, predict 2010 and waters, the year two thousand twenty PORT OF TIANJIN ship collision frequency.

Set up Calculation of Ship Grounding's risk assessment and forecast model:

The PORT OF TIANJIN main channel be the turnover PORT OF TIANJIN must through the road, be waters, PORT OF TIANJIN vessel traffic close quarters.The historical waterborne traffic casualty data in PORT OF TIANJIN shows that grounding accident mostly occurs at the shallow water area of main channel both sides, so waters, PORT OF TIANJIN Calculation of Ship Grounding's risk investigation mainly is the stranded risks of assessment boats and ships in the main channel navigation.

Its concrete steps are:

Step 1: utilize traffic study, history data collection and expert to ask method such as visit in the research waters and obtain data and data such as the depth of water distribution in research waters, Ship Types distribution, yardstick distribution, velocity distribution, volume of traffic distribution, traffic flow Density Distribution, channel span, geography information, local safety of traffic on water regulation;

Step 2: with regard to each cell volume of vessel traffic distribution, yardstick distribution, velocity distribution, traffic flow Density Distribution, depth of water distribution, channel span etc. are analyzed, calculated the stranded frequency of each cell;

Waters, PORT OF TIANJIN Calculation of Ship Grounding's frequency computation part model

$F_G=\underset{i=1}{\overset{U}{\mathrm{\&Sigma;}}}\underset{k=1}{\overset{T}{\mathrm{\&Sigma;}}}\underset{l=1}{\overset{S}{\mathrm{\&Sigma;}}}{N}_{\mathrm{ikl}}*\underset{W_{\mathrm{ikl}}}{\overset{\&infin;}{\&Integral;}}\frac{1}{\sqrt{2\mathrm{\&pi;}}\mathrm{\&sigma;}}{e}^{-\frac{{\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="A20071016837600182.png"\; state="\{\{state\}\}">X</figure-callout>}}^2}{{2\mathrm{\&sigma;}}^2}}\mathrm{dX}*F_1*{\mathrm{<figure-callout\; id="2"\; label="F"\; filenames="A20071016837600182.png"\; state="\{\{state\}\}">F</figure-callout>}}_2$

In the formula: the quantity of U=grid cell,

T=Ship Types number of categories,

S=Ship's Dimension number of categories,

N _Ik1In=the i master unit lattice, the boats and ships quantity of the 1st class yardstick in the k class boats and ships,

W _Ik1In=the i pair unit lattice, if the drauht of the 1st class yardstick is less than the depth of water in the k class boats and ships, apart from the middle of fairway distance,

F ₁=visibility influences parameter,

F ₂=windage parameter.

Step 3: waters ,～PORT OF TIANJIN in 2005 in 2003 transport information that investigation is collected is handled and calculated according to above-mentioned model, try to achieve～PORT OF TIANJIN in 2005 in 2003 waters Calculation of Ship Grounding's frequency distribution.

Step 4: from Calculation of Ship Grounding's frequency cells lattice distribution as can be seen, waters, PORT OF TIANJIN Calculation of Ship Grounding's risk mainly concentrates in the cell of main channel adjacent water, and especially 9+000～22+000 waters (cell 0 to cell Z), the Calculation of Ship Grounding's risk is higher.The actual geographical location map of contrast PORT OF TIANJIN grounding accident, according to the place that the higher relatively waters of the Calculation of Ship Grounding's frequency of above-mentioned Model Calculation Calculation of Ship Grounding's accident of lucky past few years just takes place frequently, this has verified this model.

Step 5: the simulation result of the comprehensive port of utilization Calculation of Ship Grounding's forecast model analyzing and processing boat analogue system, predict 2010 and waters, the year two thousand twenty PORT OF TIANJIN Calculation of Ship Grounding's frequency.

The content that is not described in detail in this instructions belongs to this area professional and technical personnel's known prior art.

Claims (5)

1, a kind of waterborne traffic risk assessment and Forecasting Methodology based on Geographic Information System, the method that is adopted is: present situation and future with a certain waters navigation risk are research object, according to this waters history and current traffic, analyze the feature of the navigation environment in waters, in conjunction with this waters waterborne traffic accident characteristic, set up ship collision, Calculation of Ship Grounding's accident risk assessment and forecast model, estimate influence and accordingly the open the navigation or air flight risk of the variation of waters navigation condition to the generation of waters navigation environment, embody the geographic distribution of waters risk intuitively, and the waterborne traffic risk in future is carried out performance prediction.

2, waterborne traffic risk assessment and Forecasting Methodology based on Geographic Information System as claimed in claim 1, it is characterized in that: the step of setting up ship collision risk assessment and forecast model is:

First step: utilize in the research waters traffic study, history data collection and expert ask method such as visit obtain Ship Types distributions in research waters, yardstick distribution, velocity distribution, meeting distance, the volume of traffic distributions, traffic flow Density Distribution, channel span, can the chance angle, geography information, local safety of traffic on water data and the data stipulated;

Second step: the geography information in combination research waters and navigation channel situation are used MapinfoProfessional software that gridding is carried out in the waters and are handled, and with regard to each cell volume of vessel traffic distribution, yardstick distribution, velocity distribution, traffic flow Density Distribution, meeting chance angle etc. are carried out refinement;

Third step: the relation of the factor such as research waters visibility, wind-force and Ship's Dimension and Collision Accidents of Ships is determined by data fitting method;

The 4th step: this waters transport information in recent years that investigation is collected is handled the encounter rate that calculates each cell, and calculate this waters ship collision frequency in recent years according to factors such as this waters visibility, wind-force and Ship's Dimensions, use Mapinfo Professional software that the geographic distribution of risk of collision is shown then;

The 5th step: use actual in recent years collision accident geographic distribution that model is verified;

The 6th step: the simulation result of the comprehensive port of utilization ship collision forecast model analyzing and processing boat analogue system, prediction is this waters ship collision frequency in the future.

3, waterborne traffic risk assessment and Forecasting Methodology based on Geographic Information System as claimed in claim 1, it is characterized in that: the step of setting up Calculation of Ship Grounding's risk assessment and forecast model is:

Step 1: utilize traffic study, history data collection and expert to ask method such as visit in the research waters and obtain data and data such as the depth of water distribution in research waters, Ship Types distribution, yardstick distribution, velocity distribution, volume of traffic distribution, traffic flow Density Distribution, channel span, geography information, local safety of traffic on water regulation;

Step 2: with regard to each cell volume of vessel traffic distribution, yardstick distribution, velocity distribution, traffic flow Density Distribution, depth of water distribution, channel span etc. are analyzed, calculated the stranded frequency of each cell;

Step 3: this waters transport information in recent years that investigation is collected is handled and calculated according to above-mentioned model, try to achieve this waters Calculation of Ship Grounding's frequency distribution in the future.

4, waterborne traffic risk assessment and Forecasting Methodology based on Geographic Information System as claimed in claim 2 is characterized in that: the relation of the factor such as waters visibility, wind-force and Ship's Dimension and Collision Accidents of Ships determines that method is in the third step:

The ship collision visibility factor is:

In the formula: the ship collision visibility factor of V-waters;

V-visibility (in the sea);

V _w-this waters ship collision visibility weight;

The ship collision windage factor is:

In the formula: this waters ship collision wind effect factor of W-;

W-wind-force (level);

W _w-this waters ship collision wind effect weight;

Ship collision/scale affects factor expression is:

T _j＝(0.297t _j1+0.102t _j2+0.237t _j3+0.363t _j4)×T _w

In the formula: T _j: this waters ship collision/scale affects factor of j cell;

t _J1: 0～5000 ton of boats and ships proportion of j cell;

Tj ₂: 5000～10000 tons of boats and ships proportions of j cell;

t _J3: 10000～20000 tons of boats and ships proportions of j cell;

t _J4: the j cell is the boats and ships proportion more than 20000 tons;

T _w: the Ship's Dimension weight.

5, waterborne traffic risk assessment and Forecasting Methodology based on Geographic Information System as claimed in claim 3, it is characterized in that: Calculation of Ship Grounding's frequency computation part model is in the step 2:

$F_G=\underset{i=1}{\overset{U}{\mathrm{\&Sigma;}}}\underset{k=1}{\overset{T}{\mathrm{\&Sigma;}}}\underset{l=1}{\overset{S}{\mathrm{\&Sigma;}}}{N}_{\mathrm{ikl}}*\underset{W_{\mathrm{ikl}}}{\overset{\&infin;}{\&Integral;}}\frac{1}{\sqrt{2\mathrm{\&pi;}}\mathrm{\&sigma;}}{e}^{-\frac{X^2}{{2\mathrm{\&sigma;}}^2}}\mathrm{dX}*F_1*F_2$

In the formula: the quantity of U=grid cell,

T=Ship Types number of categories,

S=Ship's Dimension number of categories,

N _Ik1In=the i master unit lattice, the boats and ships quantity of the 1st class yardstick in the k class boats and ships,

W _Ik1In=the i pair unit lattice, if the drauht of the 1st class yardstick is less than the depth of water in the k class boats and ships, apart from the middle of fairway distance,

F ₁=visibility influences parameter,

F ₂=windage parameter.

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