KR102230942B1 - Radon monitor with concentration compension function by a multiple linear regression and Compensation method thereof - Google Patents

Abstract

The present invention relates to a radon meter, and more particularly, to a radon meter having a concentration correction function by multiple linear regression and a correction method thereof. To this end, the sample air 156 is introduced into the chamber 150; A radon sensor 160 provided on one side of the chamber 150 to detect the concentration of radon from the sample air 156; A temperature sensor 140 for detecting the temperature of the sample air 156; A humidity sensor 170 for detecting the humidity of the sample air 156; Correction means for correcting the concentration of radon in multiple linear regression based on temperature and humidity; A radon meter having a concentration correction function by multiple linear regression, characterized in that it comprises a display 112 for outputting the corrected radon concentration is provided.

Description

Radon monitor with concentration compension function by a multiple linear regression and Compensation method thereof

The present invention relates to a radon meter, and more particularly, to a radon meter having a concentration correction function by multiple linear regression and a correction method thereof.

Radium is generated in the process of naturally decaying uranium or thorium contained in substances existing in nature into lead, and when this radium decays, radon is produced. Radon is colorless, odorless and tasteless, and is an inert gas that is nine times heavier than air. Among the numerous isotopes of radon, radon 222 has a relatively long half-life of 3.82 days, compared to other isotopes, and because it can stay in the air for a sufficient period of time, it can move farther and accumulate indoors. Radon 222 occupies the highest proportion of radon isotopes, and is therefore primarily the target of radon measurement. Radon occurs 80-90% in the soil and diffuses through pores in the soil or is released from the ground and ores of buildings. The discharged radon flows into the room through cracks in old buildings, joints, and gaps in drainage pipes. Also seasonally, radon concentration changes due to changes in temperature and humidity.

If the radon concentration stays in the body for a long time due to the increase in indoor radon concentration, the probability of radon decay in the body increases, and the radon decay in the body causes DNA mutation, causing lung cancer. 82% of the radiation a person is exposed to annually is due to natural radiation, most of which is radon. It is known through statistics that if the indoor radon concentration can be properly controlled, the probability of developing lung cancer can be suppressed by as much as 30%. Risk, according to civil Guide (A Citizen's Guide to Radon) for radon by the US EPA published, in the case of smokers living in the interior space is kept constant in the 370Bq / m ³ recommendations based on radon concentration, about 62% of lung cancer There is said to be Radon is one of the substances that humans must pay attention to as they are very closely related and have a high risk in our lives.

However, such radon cannot be detected by the human five senses, and the presence and concentration of radon can be determined only through a measuring device. There are passive radon meter products such as charcoal canister, filled film ionizer, and alpha secret detector, but these require at least 3 days to collect radon gas, and the concentration cannot be checked in real time. There is a necessary drawback.

To solve this problem, automatic radon meters that can check the concentration of radon in real time have been developed. German SARAD's RTM 2200, RTM 1688-2, DOSEman, DURRIGE's RAD7, Airthings' canary, Safety Siren's Siren pro 3, domestic FTLAB's RD200, FRD400, FRD1600, etc. In the case of professional use, the price range is high, ranging from 1 million won to 20 million won, and even for low-end households, the price is over 200,000 won.

1 is a schematic block diagram of such a conventional portable simple radon meter, and FIG. 2 is a circuit diagram of the radon sensor 60 in FIG. 1. 1 and 2, a through hole through which the sample air 56 can flow is formed in the lower portion of the chamber 50, and the radon ions contained in the sample air 56 are the radon sensor 60 During collision, the output voltage 68 fluctuates in a pulse form. For this, the radon sensor 60 uses a semiconductor-type PIN PHOTO diode 64.

The control unit 30 counts the pulse voltage output from the radon sensor 60 and outputs a concentration of radon proportional to the count.

However, such a portable simple radon meter 10 is inexpensive, and instead of being easy to carry, a concentration error is large and a lot of time (eg, 48 hours) is required for measurement. In other words, when the measurement started, no concentration value could be obtained for 48 hours, and I had to wait and wait.

On the other hand, the precision radon meter 80 (refer to FIG. 4, brand name "RAD7") is large, heavy, and expensive equipment, but can measure radon concentration very accurately. Therefore, the radon concentration of the precision radon measuring instrument 80 is highly trusted worldwide, and the concentration of the output radon is regarded as a standard value, and is used for calibration of other radon measuring instruments.

Meanwhile, the simple radon measuring device 10 or the precision radon measuring device 80 as shown in FIG. 1 is very sensitive to the temperature and humidity of the sample air. In order to solve this problem, the precision radon meter 80 has a separate configuration for lowering humidity and maintaining a constant temperature by providing a dehumidifying filter at the inlet side.

However, it is difficult to provide a separate dehumidifying filter or a thermostat in the portable simple radon meter 10 as shown in FIG. 1. Therefore, in the portable simple radon meter 10, there is a vicious cycle in which the measurement accuracy is further lowered due to the influence of temperature and humidity.

1. Development of high sensitivity radon detectors (Nuclear Instruments and Methods in Physics Research A 421 (1999) 334-341). Y. Takeuchi et al. 2.The influence of enviromental parameters in electrostatic cell radon monitor response (Applied Radiation and Isotopes 61 (2004) 243-247), V. Roca et al. 3.A very low-cost alpha-particle spectrometer (Meas. Sci. Technol. 19 (2008) 057001), Vujo.

Accordingly, the present invention has been conceived to solve the above problems, and an object of the present invention is to develop a low-cost portable and simple distribution type radon meter using an inexpensive semiconductor device such as a pin photo diode, multiple linear regression analysis It is to provide a radon meter having a concentration correction function by multiple linear regression that can greatly improve the radon concentration measurement accuracy of a radon meter by correcting the change in radon concentration according to temperature and humidity, and a correction method thereof.

However, the technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems that are not mentioned are clearly to those of ordinary skill in the technical field to which the present invention belongs from the following description. It will be understandable.

In order to achieve the above technical problem, the sample air 156 is introduced into the chamber 150; A radon sensor 160 provided on one side of the chamber 150 to detect the concentration of radon from the sample air 156; A temperature sensor 140 for detecting the temperature of the sample air 156; A humidity sensor 170 for detecting the humidity of the sample air 156; Correction means for correcting the concentration of radon in multiple linear regression based on temperature and the humidity; A radon meter having a concentration correction function by multiple linear regression, characterized in that it comprises a display 112 for outputting the corrected radon concentration is provided.

In addition, the radon sensor 160 includes a pin photo diode 64.

In addition, the radon sensor 160 outputs the number of collisions of radon ions colliding with the pin photodiode 65 as a count (n), and the correction means determines the concentration of radon based on the count (n), temperature, and humidity. Correct.

In addition, the correction means corrects the concentration of radon by the following equation,

Here, count (n) is a natural number, temperature is in °C, and relative humidity is in %.

In addition, the radon measuring device 100 is a portable simple radon measuring device, and the radon measuring device 100 is a target model to correct the output of the precision radon measuring device 80 that measures the concentration with relatively more precision.

Further, at the lower portion of the chamber 150, a through hole 154 formed so that the sample air 156 can be introduced; And a filter 152 that blocks the inflow of light into the through hole 154.

In addition, the radon sensor 160, the temperature sensor 140, the humidity sensor 170, the correction means and the display 112; further includes a control unit 130 for controlling, the control unit 130 is calibrated during the measurement The concentration of radon is output to the display 112.

An object of the present invention as described above is another category, wherein the sample air 156 flows into the chamber 150 for a predetermined period of time, and the radon sensor 160 counts (n) the number of collisions of radon ions (S100). ); The temperature sensor 140 detects the temperature of the sample air 156, and the humidity sensor 170 detects the humidity of the sample air 156 (S120); A step (S140) of correcting the concentration of radon in multiple linear regressions based on the count (n), the temperature, and the humidity by the correction means (S140); And storing the corrected radon concentration in the memory 120 and outputting it to the display 112 (S160) by the control unit 130; It can also be achieved by the method of correcting the concentration of.

In addition, when the corrected radon concentration is greater than or equal to the reference value, the alarm unit 118 further includes a step S180 of outputting a warning sound.

In addition, the predetermined period is in the range of 1 hour to 72 hours.

In addition, the correction step (S140) corrects the concentration of the radon by the following equation,

Here, count (n) is a natural number, temperature is in °C, and relative humidity is in %.

In addition, the controller 130 may output the corrected radon concentration to the display 112 even during measurement.

According to an embodiment of the present invention, a change in radon concentration according to temperature and humidity can be corrected without a separate dehumidification filter or thermostat. Therefore, although it is an inexpensive portable simple radon meter, it has a characteristic that can exhibit measurement accuracy comparable to that of a precision radon meter.

However, the effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those of ordinary skill in the art from the following description. I will be able to.

The following drawings attached in the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the present invention to be described later. It is limited only to and should not be interpreted.
1 is a schematic block diagram of a conventional portable simple radon meter;
2 is a circuit diagram of the radon sensor 60 in FIG. 1,
3 is an internal photograph of a radon measuring device having a concentration correction function by multiple linear regression, as an embodiment of the present invention;
4 is a photograph of experimenting with the radon measuring instrument and the precision radon measuring instrument shown in FIG. 3 under the same conditions;
5 is a schematic block diagram of the radon meter shown in FIG. 3;
6 is a flowchart showing a method of calibrating a radon meter having a concentration correction function by multiple linear regression according to an embodiment of the present invention;
7A to 7C are scatter plots showing temperature correlation with radon concentration using Spearman correlation coefficient under conditions for each relative humidity,
7D to 7F are scatter plots showing the correlation of relative humidity to radon concentration using the Spearman correlation coefficient under temperature-specific conditions,
8 is a graph showing the normalized sensitivity change of the radon meter for each relative humidity.
9A is a graph of RMSE of radon concentration values calculated by simple linear regression,
9B is an RMSE graph of randon concentration values calculated by multiple linear regression according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. However, since the description of the present invention is merely an embodiment for structural or functional description, the scope of the present invention should not be construed as being limited by the embodiments described in the text. That is, since the embodiments can be variously changed and have various forms, the scope of the present invention should be understood to include equivalents capable of realizing the technical idea. In addition, since the object or effect presented in the present invention does not mean that a specific embodiment should include all or only such effects, the scope of the present invention should not be understood as being limited thereto.

The meaning of the terms described in the present invention should be understood as follows.

Terms such as "first" and "second" are used to distinguish one component from other components, and the scope of rights is not limited by these terms. For example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component. When a component is referred to as being "connected" to another component, it should be understood that although it may be directly connected to the other component, another component may exist in the middle. On the other hand, when a component is referred to as being "directly connected" to another component, it should be understood that there is no other component in the middle. On the other hand, other expressions describing the relationship between components, that is, "between" and "just between" or "neighboring to" and "directly neighboring to" should be interpreted as well.

Singular expressions are to be understood as including plural expressions unless the context clearly indicates otherwise, and terms such as "comprises" or "have" refer to the specified features, numbers, steps, actions, components, parts, or these. It is to be understood that it is intended to designate that a combination exists and does not preclude the presence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the field to which the present invention belongs, unless otherwise defined. Terms defined in commonly used dictionaries should be interpreted as having meanings in the context of related technologies, and cannot be interpreted as having an ideal or excessively formal meaning unless explicitly defined in the present invention.

Example of Configuration

Hereinafter, a configuration of a preferred embodiment will be described in detail with reference to the accompanying drawings. 3 is a picture of the inside of a radon meter 10 having a concentration correction function by multiple linear regression as an embodiment of the present invention. As shown in FIG. 3, a chamber 50 is provided on a substrate (not numbered), a control unit 130 is mounted, and an LCD display 112 is provided on one side.

4 is a photograph of an experiment of the radon meter and the precision radon meter shown in FIG. 3 under the same conditions. As shown in Fig. 4, the radon measuring device 100 and the precision radon measuring device 80 of the present invention are simultaneously measured in the same experimental space 90 to compare the radon concentration.

5 is a schematic block diagram of the radon meter 100 shown in FIG. 3. As shown in Fig. 5, the radon meter 100 is approximately a chamber 150, an alarm unit 118, a memory 120, a display 112, a power supply unit 114, a communication unit 116, a temperature sensor 140 ), and a humidity sensor 170.

The interior of the chamber 150 is emptied by a predetermined volume, and a plurality of through holes 154 are formed in the lower substrate. A mesh filter 152 for blocking the inflow of light is further installed in the through hole 154. The inner surface of the chamber 150 includes an ion coating layer to activate radon ions and promote collision with the radon sensor 160.

The radon sensor 160 includes a pin photo diode 64 as shown in FIG. 2. The configuration of the pin photo diode 64, the resistor 66, the ground, and the output voltage 68 through the Vout terminal is a known circuit, so a detailed description thereof will be omitted. The radon sensor 160 may be packaged and present in a semiconductor-like form.

The alarm unit 118 is a component for giving a warning when the displayed radon concentration is greater than or equal to a reference value. The alarm unit 118 may be composed of a buzzer, a speaker, a warning light, a warning LED, and the like.

The memory 120 is equipped with a concentration correction program and an operating program, and functions to temporarily store the measured concentration. To this end, the memory 120 may be implemented as a flash memory, RAM and ROM, SSD, microSD card, or the like.

The display 112 is a component that displays the operating state of the radon meter 100 and the corrected concentration. The display 112 may be implemented as an LCD, a seven-segment diode, or an OLED.

The power supply unit 114 is a component that supplies power to the entire radon meter 100. The power supply unit 114 may include a terminal to which external power is connected, and may be implemented as a battery or a secondary battery.

The communication unit 116 is used to transmit the measured concentration data to an external device or to update the firmware. When the communication unit 116 is wired, it may be RS-232, USB, LAN cable, RJ45, or the like. When the communication unit 116 is wireless, it may include a Wi-Fi, 4G, 5G communication network, wireless Internet, Zigbee, infrared, Bluetooth, a low-power beacon communication module, and the like.

The temperature sensor 140 measures the ambient temperature at a place where the sample air 156 and/or the radon measuring device 100 is provided.

The humidity sensor 170 measures the surrounding (relative) humidity at the place where the sample air 156 and/or the radon meter 100 is provided.

Example operation

Hereinafter, the operation of the preferred embodiment will be described in detail with reference to the accompanying drawings. 6 is a flowchart illustrating a method of calibrating a radon meter having a concentration correction function by multiple linear regression according to an embodiment of the present invention. As shown in FIG. 6, first, sample air 156 flows into the chamber 150 for a predetermined period (eg, 48 hours), and the radon sensor 160 counts (n) the number of collisions of radon ions ( S100). The sample air 156 flows into the chamber 150 through the through hole 154, and the radon ions in the sample air 156 collide with the pin photo diode 64 of the radon sensor 160, and the output voltage 68 ) To create a pulse waveform.

After shaping the pulse waveform, the controller 130 counts (counts) the number of pulses (n). Accordingly, when the concentration of radon ions contained in the sample air 156 is high, the count increases, and when the concentration is low, the count decreases.

Then, the temperature sensor 140 detects the temperature of the sample air 156, and the humidity sensor 170 detects the humidity of the sample air 156 (S120). The detected temperature and relative humidity are transmitted to the control unit 130.

Then, the correction means corrects the concentration of radon in multiple linear regression based on the count (n), temperature and humidity (S140). At this time, the correction is made by [Equation 4].

[Equation 4]

Here, the count (n) is a natural number (n=0, 1, 2, 3...), the temperature is in °C, and the relative humidity is in %.

Then, the control unit 130 stores the concentration of radon corrected by [Equation 4] in the memory 120 and outputs it to the display 112 (S160).

And, if the corrected radon concentration is ^{more than the reference value (370Bq/m 3} ), the alarm unit 118 outputs a warning sound (S180).

In addition, the control unit 130 may output the corrected radon concentration according to [Equation 4] to the display 112 in real time based on the input count (n), temperature, and humidity, even during measurement.

Example of Experiment method

Hereinafter, experiments and experimental results of a preferred embodiment will be described in detail with reference to the accompanying drawings. FIG. 4 is a photograph of an experiment of the radon measuring instrument 100 and the precision radon measuring instrument 80 shown in FIG. 3 under the same conditions. As shown in FIG. 4, the precision radon meter 80 used high-precision "RAD7" to measure the reference radon concentration. The radon meter 100 and the precision radon meter 80 of the present invention measured the value of the radon count (n) at 1 hour intervals. The temperature sensor 140 and the humidity sensor 170 measured temperature and relative humidity at 1-minute intervals, respectively, and calculated an average value in 1-hour increments. The experiment was carried out 9 times as shown in [Table 1], and 72 hours were measured for each experiment.

10℃ 20℃ 30℃ RH 20% Experiment(1) Experiment(2) Experiment(3) RH 50% Experiment(4) Experiment(5) Experiment(6) RH 80% Experiment(7) Experiment(8) Experiment(9)

As shown in [Table 1], in order to find out the change in radon concentration according to changes in temperature and humidity, the relationship between temperature and relative humidity on radon concentration was determined by calculating the scattering point and Spearman correlation coefficient of temperature and relative humidity. For statistical analysis, the SPSS18 program was used.

The value obtained by dividing CPD (Cycle Per Day), which represents the number of times the radon meter 100 counts during the day, by the average radon concentration value for the day, represents the sensitivity (CPD/Bqm-3) of the radon meter. And, by calculating the sensitivity (CPD/Bqm-3) of the radon meter 100 at each temperature and relative humidity condition for 72 hours of data used in each temperature and relative humidity condition of [Table 1], The effect of changes in temperature and relative humidity on the sensitivity of the radon meter 100 was evaluated.

A simple linear regression equation for converting the radon count (n) value of the radon meter 100 into a radon concentration value without correction of temperature and relative humidity was obtained as shown in [Equation 1].

And, the radon concentration measurement value of the precision radon measuring instrument 80 according to the change in temperature and relative humidity targeting the 48-hour average data of the data obtained through the temperature and relative humidity correction experiment and the radon measuring instrument calculated by [Equation 1] Multilinear regression analysis is performed with the difference between the measured values of radon concentration in (100) as the dependent variable, temperature and relative humidity as independent variables, and the radon concentration to which the correction according to the temperature and relative humidity values is applied is calculated. The regression equation was generated as in [Equation 2].

Example of Experiment result

The effect of temperature and relative humidity on the indoor radon concentration change is as follows.

Experiment Temperature(℃) Relative humidity (%) Radon Count (n) Radon concentration (Bqm-3) Experiment(1)
Experiment(2)
Experiment(3) 9.99±0.37
21.14±0.62
29.97±0.69 19.66±0.90
20.18±1.18
21.54±0.62 1.06±0.73
0.85±0.78
0.69±0.72 59.39±9.56
51.84±7.14
45.07±9.69 Experiment(4)
Experiment(5)
Experiment(6) 9.59±0.50
19.90±0.49
31.12±0.41 50.92±1.03
50.28±0.86
49.56±1.05 0.85±0.76
0.69±0.62
0.57±0.60 63.14±10.53
56.32±9.85
46.73±7.66 Experiment(7)
Experiment(8)
Experiment(9) 10.08±0.39
20.56±0.55
29.56±0.72 79.58±0.63
80.39±1.12
81.10±0.84 0.82±0.76
0.68±0.77
0.51±0.60 68.34±10.74
59.31±7.85
49.04±9.26

[Table 2] shows the mean±SD values of the temperature, relative humidity, radon counter (n), and radon concentration measured for each 72 hours in a total of 9 experiments. As shown in [Table 2], it can be seen that the temperature and relative humidity were kept constant under the conditions set during the experiment.

Spearman
Correlation coefficient Temperature and radon concentration Humidity and radon concentration 20% relative humidity
(n=216) 50% relative humidity
(n=216) 80% relative humidity
(n=216) Temperature 10℃
(n=216) Temperature 20℃
(n=216) Temperature 30℃
(n=216) r -0.49 -0.54 -0.56 0.23 0.32 0.09 p-value ≤0.01 ≤0.01 ≤0.01 ≤0.01 ≤0.01 0.17

And, [Table 3] shows the Spearman correlation coefficient between temperature and relative humidity and radon concentration in each temperature and relative humidity condition. (1) For both temperature and radon concentration, r=-0.49 when the relative humidity is 20% at p-value≤0.01, r=-0.54 when the relative humidity is 50%, and r=- when the relative humidity is 80% It was 0.56. This indicates that there is a negative correlation between the two variables under all relative humidity conditions. And (2) In the case of relative humidity and radon concentration, when the temperature is 10 degrees and 20 degrees, r=0.23 and r=0.32, respectively, showed that there was a weak positive correlation between the two variables, but when the temperature was 30 degrees, There was no statistically significant correlation from p=0.172 to r=0.093.

7A to 7C are scatter plots showing the temperature correlation with the radon concentration using the Spearman correlation coefficient under conditions for each relative humidity, and FIGS. 7D to 7F are relative to the radon concentration using the Spearman correlation coefficient at each temperature It is a scatter plot showing the humidity correlation. As can be seen through the scatter plots shown in FIGS. 7A to 7F, the correlation between the temperature and the relative humidity with respect to the radon concentration was confirmed under each temperature and relative humidity condition described by the Spearman correlation coefficient.

In addition, the influence of temperature and relative humidity on the sensitivity of the radon meter 100 is as follows.

Relative humidity (%) 20 50 80 Temperature(℃) 10 0.429 (1.437) 0.325 (1.089) 0.291 (0.994) 20 0.393 (1.318) 0.298 (1.000) 0.275 (0.943) 30 0.373 (1.249) 0.293 (0.983) 0.253 (0.923)

[Table 4] shows the change in sensitivity (CPD/Bqm-3) of the radon meter 100 for each relative humidity and temperature. Through the sensitivity value normalized based on the sensitivity value at a temperature of 20 degrees and a relative humidity of 50%, it can be seen that the sensitivity of the radon meter 100 is significantly affected by the change in relative humidity than the temperature. The more sensitive it is, the higher the sensitivity.

8 is a graph showing the normalized sensitivity change of the radon meter for each relative humidity. As shown in FIG. 8, it can be seen that the sensitivity decreases as the relative humidity increases in all temperature conditions, and in particular, when the relative humidity increases from 20% to 50%, it can be seen that the sensitivity decreases significantly (the sensitivity is 0.90 to 1.00). In addition, as the temperature increases, the sensitivity tends to decrease under the same relative humidity condition, but it can be seen that the effect is relatively small compared to the relative humidity.

Temperature and humidity correction of the radon meter 100 using multiple regression analysis are as follows.

variable Adjusted R ² RMSE(Bq/m ³ ) Beta Standardized
Beta P-value Constant 0.995 11.645 -8.065 - - Radon count 92.735 0.997 <0.001

[Table 5] is the result of simple linear regression analysis for the experimental data (n=235) averaged for 48 hours, A high R ² value of 0.995 and a low RMSE (Root Mean Square Error) value of 11.645 were shown.

[Equation 3] represents a linear regression equation for converting the radon count (n) value of the radon meter 100 calculated by linear regression analysis into radon concentration.

variable Adjusted R ² RMSE(Bq/m ³ ) Beta Standardized
Beta P-value Constant 0.802 5.665 -42.075 - - Temperature 0.586 0.385 <0.001 Humidity 0.421 0.810 <0.001

[Table 6] targets data obtained by averaging data measured through temperature and relative humidity correction experiments for 48 hours (n=225), between the radon concentration of the precision radon meter 80 and the radon concentration of the radon meter 100 This is a multilinear regression analysis between the difference value of and temperature and relative humidity. As a result, a high R ² value of 0.802 and a low RMSE value of 5.665 were shown.

Here, radon count (n) is a natural number, temperature is in °C, and relative humidity is in %. Accordingly, [Equation 4] represents a multiple linear regression equation for correcting the radon concentration using the radon count value, temperature, and relative humidity measurement value of the radon meter 100 calculated through multiple linear regression analysis.

Experiment Measuring conditions RMSE(Bq/m3) Temperature Relative humidity Simple linear regression Multiple linear regression Experiment (1) (n=25) 9.99 19.66 32.622 5.849 Experiment (2) (n=25) 21.14 20.18 21.224 10.071 Experiment (3) (n=25) 29.97 21.54 18.289 3.709 Experiment (4) (n=25) 9.59 50.92 14.673 5.033 Experiment (5) (n=25) 19.90 50.28 2.821 8.530 Experiment (6) (n=25) 31.12 49.66 3.241 1.566 Experiment (7) (n=25) 10.08 79.58 5.723 3.896 Experiment (8) (n=25) 20.56 80.39 4.858 2.559 Experiment (9) (n=25) 29.56 81.10 6.783 3.653 Sum (n=255) 20.20 50.37 15.582 5.627

[Table 7] is a comparison of the RMSE of the simple linear regression equation and the multiple linear regression equation calculated from each experimental result. For the total experimental results (n=255), RMSE of the radon concentration value calculated by the simple linear regression equation is 15.582, and the RMSE of the radon concentration value calculated by the multiple linear regression equation is 5.627. From this, it can be seen that the RMSE was greatly reduced by the correction using the temperature and relative humidity values.

9A is a graph of RMSE of radon concentration values calculated by simple linear regression, and FIG. 9B is a graph of RMSE of randon concentration values calculated by multiple linear regression according to the present invention. 9A and 9B, in the case of the simple linear regression equation of FIG. 9A, the RMSE was the lowest at a temperature of 20 degrees and a relative humidity of 50%, and the highest RMSE was shown at a temperature of 10 degrees and a relative humidity of 20%.

In the case of the multiple linear regression equation as shown in FIG. 9B, it can be seen that the overall RMSE is lower than that of the simple linear regression equation. In particular, when the relative humidity is 50% and the temperature is 10 degrees, it can be seen that the RMSE is significantly reduced compared to the simple linear regression equation.

Detailed description of the preferred embodiments of the present invention disclosed as described above has been provided to enable those skilled in the art to implement and practice the present invention. Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the scope of the present invention. For example, a person skilled in the art may use the components described in the above-described embodiments in a manner that combines them with each other. Accordingly, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The present invention may be embodied in other specific forms without departing from the spirit and essential features of the present invention. Therefore, the detailed description above should not be construed as restrictive in all respects and should be considered as illustrative. The scope of the present invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention. The invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. In addition, the embodiments may be configured by combining claims that do not have an explicit citation relationship in the claims, or may be included as new claims by amendment after filing.

10: radon meter,
12: display,
14: power supply,
16: communication department,
18: alarm unit,
20: memory,
50: chamber,
54: through hole,
56: sample air,
60: radon sensor,
62: radon ion,
64: pin photo diode,
66: resistance,
68: output voltage,
80: precision radon meter,
90: experiment space,
100: radon meter,
112: display,
114: power supply,
116: communication department,
118: alarm unit,
120: memory,
130: control unit,
140: temperature sensor,
150: chamber,
152: mesh filter,
154: through hole,
156: sample air,
160: radon sensor,
170: humidity sensor.

Claims (12)

A chamber 150 into which the sample air 156 is introduced;
A radon sensor 160 provided on one side of the chamber 150 to detect the concentration of radon from the sample air 156;
A temperature sensor 140 for detecting the temperature of the sample air 156;
A humidity sensor 170 for detecting the humidity of the sample air 156;
Correction means for correcting the concentration of radon in multiple linear regressions based on the temperature and the humidity;
Includes; a display 112 for outputting the corrected radon concentration,
The radon sensor 160 includes a pin photo diode 64,
The radon sensor 160 outputs the number of collisions of radon ions colliding with the pin photo diode 65 as a count (n),
The correction means corrects the concentration of radon by the following equation based on the count (n), the temperature and the humidity,

Here, the count (n) is a natural number, temperature is a unit of °C, a radon meter having a concentration correction function by multiple linear regression, characterized in that the unit of %. delete delete delete The method of claim 1,
The radon meter 100 is a portable simple radon meter,
The radon measuring device 100 is a radon measuring instrument having a concentration correction function by multiple linear regression, characterized in that the target model to correct the output of the precision radon measuring instrument 80 that measures the concentration relatively more precisely. The method of claim 1,
In the lower part of the chamber 150,
A through hole 154 formed to allow the sample air 156 to flow in; And
A radon meter having a concentration correction function by multiple linear regression, characterized in that a filter (152) for blocking the inflow of light into the through hole (154). The method of claim 1,
The radon sensor 160, the temperature sensor 140, the humidity sensor 170, the correction means and the display 112; further comprises a control unit 130 for controlling,
The control unit 130 outputs the corrected radon concentration to the display 112 even during measurement. A radon meter having a concentration correction function by multiple linear regression. The sample air 156 is introduced into the chamber 150 for 1 hour to 72 hours, and the radon sensor 160 counts (n) the number of collisions of radon ions (S100);
The temperature sensor 140 detects the temperature of the sample air 156, and the humidity sensor 170 detects the humidity of the sample air 156 (S120);
A step of correcting the concentration of radon in multiple linear regression based on the count (n), the temperature, and the humidity (S140); And
The control unit 130 stores the corrected radon concentration in the memory 120 and outputs it to the display 112 (S160); Including,
The correction step (S140) corrects the concentration of the radon by the following equation,

Here, the count (n) is a natural number, temperature is in °C unit, the relative humidity is a concentration correction method of a radon meter having a concentration correction function by multiple linear regression, characterized in that the unit of %. The method of claim 8,
When the corrected radon concentration is greater than or equal to a reference value, the alarm unit 118 outputs a warning sound (S180). delete delete The method of claim 8,
The control unit 130 outputs the corrected radon concentration to the display 112 even during measurement.

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