KR20130125391A - Method of searching for unsteady dust source position of dustfall - Google Patents

Abstract

At the coordinate points p in the first and second source search areas γ (i _M ) and γ (i _N ) having evaluation centers i _M , i _N as starting points and having a central axis extending in the direction of the wind direction of the representative wind direction WD. evaluation points in i _M, multiplied by a central axis perpendicular to the cross-sectional area S _p1, factor B ₁ to S _p2 of the oscillation of the i _N original search range for calculating the home oscillation amount E _1, E _2, and assumes the oscillation amount of E _1, A method for searching for an abnormal oscillation source position of the falling out stock, which determines whether the ratio of E ₂ is within a predetermined range.

Description

METHODS OF SEARCHING FOR UNSTEADY DUST SOURCE POSITION OF DUSTFALL}

The present invention relates to a technique for searching for an oscillation source of falling dust in the atmosphere.

This application claims priority based on Japanese Patent Application No. 2011-108105 for which it applied to Japan on May 13, 2011, and Japanese Patent Application No. 2012-057297 for which it applied in Japan on March 14, 2012. The contents thereof are used herein.

When a nuclear power plant is destroyed by an accident, grasping the behavior of radioactive sedimentation spreading around from a plurality of radio oscillation facilities is an important industrial problem in recent years. In addition, falling sales occur in various industries such as agriculture and forestry. Falling sales from the natural world, such as sand dunes, cannot be ignored. When there are a large number of oscillation sources that can be the source of falling sales, as a effect on the "measured value of the falling sales amount" at the evaluation point of falling sales, the technique which analyzes which contribution source contributes largely, It is important in managing these falling sales and taking measures.

From this point of view, Patent Literatures 1 to 4 disclose techniques for evaluating the amount of sold out of a plurality of sources from the amount of sold out sold measured at the evaluation point, that is, a technique for searching for a major source of falling sold out.

First, Patent Literature 1 discloses the following technique. That is, a model suitable for simulation is selected from input conditions such as atmospheric conditions, weather data, and terrain data in the evaluation range of air pollutant diffusion. Furthermore, the adjustment input parameter is selected from the measured value according to this input condition. Then, input data is generated from the analysis conditions of the selected model and the selected adjustment input parameters, the simulation is performed, the deviation between the result and the emission source measured value data is calculated, and the emission source corresponding to the data having the minimum deviation is selected. Estimate.

Further, Patent Document 2 discloses the following technique. That is, in the atmospheric observation station, the normal emissions emitted from the source during the period in which the atmospheric chemical concentration measured in advance does not exhibit abnormally high concentrations, and the chemicals emitted from the source during the period during which the chemical concentrations in the atmosphere show abnormal high concentrations. In case of abnormality, emissions are obtained. And the source which causes the abnormal high density | concentration of the chemical substance in air | atmosphere is identified by finding the solution which the sum of the squares of the normal discharge | emission (ordinary discharge | elapsed discharge | emission) is minimum.

In addition, Patent Literature 3 discloses the following technique. That is, the amount of scattering dust and the direction of the wind direction are measured at a pitch of a predetermined time at a plurality of arbitrary measurement points around the plurality of dust generation points over a suitable period. Next, the average amount of scattering dust is calculated for each wind direction in the measurement points from the amount of scattering dust and the direction of wind direction obtained. Next, on the map including a plurality of dust generation points and a plurality of measurement points, a plurality of wind direction directions with a large amount of average scattering dust are plotted around each measurement point. Next, the dust generation point where the intersection point of the wind direction directions from each measurement location which were constructed is located, or when the direction of wind direction from each measurement point is substantially corresponded, the dust generation point on the map which exists in the wind direction direction It is specified as a source of scattering dust.

In patent document 4, the following technique is disclosed. That is, one or a plurality of portable self-supporting multi-sensing units for measuring the air pollution of a plurality of items are remotely controlled via a wireless or wired network to measure the air pollution of the plurality of items, and the measurement data is collected. Display.

In addition, when evaluating the density | concentration of the falling-off dust at an evaluation point from the generation amount of the dust at the generation source, a plume type is used normally. The plume type (plum model) is a kind of diffusion type and expresses the advection and diffusion as the flow of smoke. The normal solution of the concentration distribution is obtained when the wind, diffusion coefficient, and emission are made constant. Diffusion equation is a theoretical calculation formula for estimating the state that contaminants emitted from the source to the air are diffused and diffused under constant weather conditions, and for estimating the concentration of the pollutants in the environment. Supervision, 1997, Oriental Pavilion (Tokyo), p. 196]. In Patent Document 5, a standard plume equation (1) is shown as an atmospheric diffusion model of gas from a point source without adsorption on the ground surface.

…(1)

... (One)

Here, the meaning of the symbol of the formula (1) is as follows. In addition, the meaning of these symbols is the same also in the following description. The following symbols are all SI unit systems.

x, y, z: Three-dimensional Cartesian coordinates of the evaluation point (gas origin as origin)

x: coordinate value corresponding to the direction in which the plume center axis extends on the horizontal plane

y: Coordinate value of a direction perpendicular to the direction in which the plume center axis extends on the horizontal plane (in the following description, this direction is referred to as a "horizontal direction" as necessary).

z: coordinate in the vertical direction

C: gas concentration at the evaluation point (x, y, z) [kg / m 3, or m 3 / L]

Q _P : Generated amount of gas [㎏ / s, or ㎥ / s]

WS: Wind speed [m / s]

He: Height [m] from the ground surface of the gas generating source

σ _y , σ _z : Plume diffusion width [m] (the standard deviation of the gas concentration distribution in the direction perpendicular to the flow of gas, respectively, in the horizontal direction and in the vertical direction)

Non-Patent Literature 1 and Non-Patent Literature 2 show a plume equation (2) relating to gas having adsorption on the ground surface and fine particles (SPM: Suspended Particulate Matter) having a small drop rate.

…(2)

... (2)

Here, (alpha) of Formula (2) is represented by the following Formula (3).

…(3)

... (3)

The meaning of the symbol of Formula (3) is as follows. In addition, the meaning of these symbols is the same also in the following description.

V _d : Deposition speed [m / s]

V _s : Falling speed [m / s] (for SPM, 0 for gas)

Here, σ _y and σ _z are characteristic values for indicating the "plum diffusion width" in the direction perpendicular to the plume central axis, and the concentration becomes the standard deviation when assuming the concentration distribution of the Gaussian distribution in the plume center axis vertical direction. The distance between the point and the plume's central axis is used.

In addition, a plum type is not limited to what was shown by Formula (1). For example, Non-Patent Document 3 discloses a plume equation in which a double Gaussian distribution of concentration is assumed and a curve is used for the plume central axis.

The characteristics common to these plume expressions are, firstly, the concentration values of specific concentration evaluation points are expressed by a function expression such as the coordinate values of the evaluation point and the source, the speed of occurrence at the source, weather conditions such as wind direction and wind speed, and the result. Is uniquely given. Second, in the concentration calculation, assuming the central axis, "plum" is formed which forms a high concentration region characterized by "plum diffusion width" σ _y and σ _z around the central axis. Comparing the plume method with another method, the numerical analysis method of numerically solving a plurality of simultaneous physics equations and calculating the concentration value of a specific concentration evaluation point has a point or calculation result for calculating the concentration without assuming a plume. It is different from plum type in that it is not unique. In addition, since the concentration value of a specific concentration evaluation point is obtained by simply varying the evaluation point, the coordinate value of the source, the occurrence speed at the source, and weather conditions such as the wind direction and the wind speed, the multiple regression equation and the plum are not assumed. It is not an expression.

Here, "term multiplied by (alpha)" in Formula (2) inverts the shape of the distribution of the gas or SPM in the vertical direction symmetrically on the ground surface, so that gas or SPM is retained without adsorption above the ground surface. The effect is expressed, and the effect of adsorption to the index of gas and SPM is adjusted by the magnitude of α. In addition, in the following description, the "term multiplied by (alpha)" in Formula (2) is called "surface surface antireflection" as needed.

In addition, Patent Literature 6 discloses the following technique as a technique for measuring the amount of falling sales at an evaluation point in a short period of about 10 minutes. That is, the measurement of mass is continuously carried out separately for coarse particles and microparticles by using a funnel-shaped particle collecting port having an open upper side, an air flow path circulating in the measuring device, and an inertial classifier disposed in the middle of the air flow path. Do it. Then, from the measured value of the mass of the coarse particles, the change in the dropping speed of the falling dust in the air is calculated.

However, the above-described prior art has the following problems.

That is, as a 1st problem, the thing of the object searched for a generation source is not falling-out.

For example, in the technique of patent documents 1-4, the object which searches for a generation source is gas. In the technique of patent document 3, only the SPM is contained in the target which searches for a generation source. SPM is a much smaller particle compared to falling dust (by definition, SPM is a particle having a diameter of 10 μm or less), and the behavior of diffusion in the atmosphere is substantially the behavior of the gas except for generating a fine particle settling. Is equivalent to

On the other hand, falling dust is a much larger sold particle | grains than the SPM (particle of about 10 micrometers or more in diameter), and the fall speed is extremely large. For this reason, the behavior of the diffusion of the falling dust in the atmosphere is greatly influenced by the falling rate of the particles. Therefore, the behavior of the diffusion of the falling dust is significantly different from that of the gas.

In addition, the quantity of the drop-off sold as the object of observation and management here is the deposition amount of the drop-off sold to the ground surface. In the technologies of Patent Documents 1 to 4, since the gas and the SPM concentration at the evaluation point are to be observed and managed, the deposition rate of gas and SPM on the ground surface can not be directly known. Certainly, since the deposition rate V _d is described in the above formula (2), if the deposition rate V _d can be accurately provided, it is possible to convert the concentration of the gas and the SPM on the evaluation point into the deposition amount on the ground surface. Do.

However, as described in Non-Patent Document 1, the deposition rate V _d of the SPM fluctuates greatly under the influence of the surface state and turbulence of the atmosphere. In addition, a method of generally giving a deposition rate of gas has not been developed. Therefore, to accurately provide values of the deposition rate V _d, and in fact is very difficult, it is targeted to drop sold in the technology of Patent Document 1 to 4, it is difficult, at least quantitatively.

As a second problem, there has conventionally been no method for searching for an oscillation source for falling sales. This is based on the premise of the search of a generation source in a horizontal plane (surface surface), as represented by patent document 3 in the conventional search method of a generation source. For this reason, in the conventional method for searching for a generation source, it is difficult to treat the generation source of the falling dust, which has a large drop rate V _s of the particles and a problem of the amount of deposition on the ground surface, in three dimensions. In particular, in the case of the method of extending the search line of the generation source from the evaluation point in the wind direction as disclosed in Patent Document 3, the surface surface reflection (α · exp [− (He + z−V _s x) in Equation (2). / WS) ² / 2σ _z ² ]) is difficult to deal with quantitatively and in general, and therefore, an effective method for associating a search line of a source with a plume expression has not been proposed.

As a third problem, in the above-described prior art, a procedure for presuming the position of the source and the amount of outline generated therein is essential when searching for the source.

For example, in the techniques of Patent Documents 1 and 2, first, the relationship between the amount of generation at an arbitrary source and the concentration at an arbitrary evaluation point for all of the sources and all the evaluation points assumed in advance is determined by the above- As a function of weather conditions. Next, the parameters of the function (σ _y , Q _P, etc.) are adjusted by the optimization method so that the difference between the measured value of the concentration at all the evaluation points and the predicted value of the concentration is minimized. Therefore, at least, it is necessary to give the position of all the generation sources beforehand. In addition, in order to ensure the validity of the calculation process of an optimization method, it is generally preferable to give the generation amount of the outline in each generation source as an initial condition beforehand. This is because, in the optimization problem, when an initial condition extremely dissociated from the actual condition is given, the solution may converge at a local stability point that is significantly different from the actual condition.

In addition, in the technique of patent document 3, after assuming the generation | occurrence | production point of several dusts (SPM), etc., the density | concentration of SPM in several surrounding evaluation points etc. is measured for a long time, and each evaluation within this period. The mean value of the concentration of the SPM for each wind direction is obtained at the point, and in the wind direction of the wind direction in which the mean value of the SPM concentration is the largest, the source search lines are extended in the horizontal plane (surface) from a plurality of evaluation points, and these source search lines are It is determined that the point which coincides with any one of the generation points of dust SPM among the intersections which mutually crossed each other is a generation place where the generation amount of dust SPM is large.

In addition, in the technique of patent document 4, since it is assumed that a measuring instrument is installed in the vicinity of the assumed generation source, the generation source should be known beforehand.

However, in the case where there are a large number of sources, it is difficult to actually grasp all of the locations of these sources and the amount of outline generation in advance, which is difficult in practice and, if possible, requires huge resources and is not suitable. In addition, the source of oscillation may not be accessible in the first place, such as an accident at a nuclear power plant. Therefore, in the technique of patent documents 1-4, there exists a problem that it can apply effectively only in the environment where the number of generation | generation sources is very few or it can grasp | generate generation | occurrence | production amount of generation | generation sources sufficiently correctly.

As a fourth problem, in the prior art, the source to be searched is basically a normal source in which the generation amount does not fluctuate in time, or a quasi-normal oscillation source in which the generation amount only fluctuates slightly in the vicinity of the time average value. .

For example, in the technique of patent documents 1 and 2, in order to apply an optimization method, generally, the number of evaluation points should be set more than the number of parameters which can be adjusted among functions, such as a plume type to which it applies. This is because, if the number of adjustable parameters is substantially larger than the number of evaluation points, the solution obtained is generally not uniquely determined and therefore is broken as a method.

In addition, when a large number of sources exist, the number of evaluation points is often set to be smaller than the number of sources in view of economics. Even in such a case, if the generation source is limited to a normal generation source (that is, the generation amount Q _P is not an adjustable parameter), the measurement value of the number of generation sources or more can be determined by using the measurement values at evaluation points at a plurality of different times. Can be secured and optimization methods can be applied. On the other hand, when the generation amount Q _P is to apply the techniques of Patent Documents 1 and 2 with respect to an unusually large variations in, the abnormal source, the generation amount Q _P, should be as adjustable parameters. For this reason, when a large number of generation sources are to be searched, it is necessary to provide an extremely large number of evaluation points exceeding the number of generation sources, which is not practical from the viewpoint of economics.

In addition, in the technique of patent document 3, the density | concentration data of SPM of the evaluation point collected discretely within the period of two months or more is averaged, and a generation source is searched for. Therefore, the generation source is limited to the normal generation source.

In addition, in the technique of patent document 4, since an evaluation point is arrange | positioned in the vicinity of the assumed generation source, an abnormal generation source can be searched in principle. However, in this technique, when gas from a plurality of sources reaches a specific evaluation point at the same time, a method for determining which of the plurality of sources is an excellent source is not disclosed, and all assumed The establishment of an evaluation point in the vicinity of a generation source is not described. Therefore, it is possible to search for an abnormal oscillation source in this technique only when the distance between the generating sources is far enough so as not to influence each other. In other words, this technique can be applied only when the source and the evaluation point correspond one-to-one substantially.

However, in the actual generation source, the generation amount is generally large, and fluctuates with time. Therefore, in the prior art, which targets only a normal source or a source in which the source and the evaluation point correspond one-to-one, there is a problem that it cannot be sufficiently applied to the search for a real source.

In addition, when the sold out is radioactive, the radiation dose such as α-ray, β-ray, or γ-ray of the sold-out can be measured by the method disclosed in patent documents 7-9.

Japanese Patent Application Publication No. 2003-255055 Japanese Patent Application Publication No. 2005-292041 Japanese Patent Application Laid-open No. 2004-170112 Japanese Patent Application Publication No. 2003-281671 Japanese Patent Application Publication No. 2007-122365 Japanese Patent Application Publication No. 2008-224332 Japanese Patent Application Laid-open No. Hei 8-327741 Japanese Patent Application Laid-open No. Hei 7-35900 Japanese Patent Application Publication No. 2009-63510

Suspended particulate matter measures examination society (Ministry of Environment, Air Conservation Bureau air regulation section supervision): Floating particulate matter pollution prediction manual, Oriental Hall publication, 1997 Shinichi Okamoto: Lecture on Atmospheric Environment Prediction, Kyosei, 2001 United States Environment protection agency: EPA-454 / R-03-004, 2004

This invention is made | formed in view of the above circumstances, and an object of this invention is to search efficiently and accurately the oscillation source of the falling dust which an oscillation amount (rate of occurrence of falling sales in an oscillation source) changes abnormally.

In order to solve the said subject, as a result of the inventor's research, it came to invent the following solution.

(1) The searching method of the abnormal oscillation source position of the drop-off sold out according to the first aspect of the present invention includes at least two different times with the i _t- th time for each period Δt _d as the time t _d (i _t ). The drop sale is collected in the period T _d (i _t ) which is the period from the time t _d (i _t -1) to the time t _d (i _t ) at the evaluation point described above, and the amount of the drop sale amount M per unit time is measured. In the step of setting the sold-out amount for obtaining the value and in each of the respective evaluation points, the wind direction is continuously measured in the period T _d (i _t ) with a period Δt _wint shorter than the period Δt _d , and the period T _d Wind velocity is continuously measured in the period Δt _wint in the period T _d (i _t ) in each of the representative wind direction deriving steps for deriving the representative wind direction WD in (i _t ) and each of the evaluation points. , deriving the representative wind speed of deriving the representative wind speed WS in the period t _{d (t} i) Jung, in each of the vicinity of the respective evaluation points, in succession to the period Δt _wint the period T _d (i _t) measuring the falling speed of the drop sold out, and in the period T _d (i _t) It has a representative fall speed derivation process for deriving a representative fall speed V _s , and a central axis extending in the wind direction of the representative wind direction WD with the first evaluation point i _M as a starting point, and searching for a dropout generating source around the central axis. A first falling dust generating source search region γ (i _M ) which forms an area width and has a range of a distance from the central axis to the falling dust generating source searching area width in a vertical direction; and the first evaluation point i _M and It is different from the first evaluation point i _N at the same time having a central axis that is the starting point, and extended in the upwind direction of the representative wind direction WD, the drop around the central axis sold source Tam The vertical direction to form a region width from said central axis to a second drop sold source search area γ (i _N) to set descent sold source search area setting step of which the distance area, the range of up to the descending sold source search area width And a coordinate point p included in both of the first drop sale source search region γ (i _M ) and the second drop sale source search region γ (i _N ), and a first point between the first evaluation point i _M. A distance calculating step of calculating a distance L _d (i _M ) and a second distance L _d (i _N ) between the coordinate point p and the second evaluation point i _N , and the first coordinate point including the coordinate point p Cross-sectional area of the first oscillation source search area in the vertical plane of the drop dust generating source search area central axis Cross-sectional area of the first oscillation source search area center axis vertical cross-sectional area S _p1 and the second drop dust generating source search including the coordinate point p spirit A cross-sectional area calculating step of calculating a second oscillation source search area central axis vertical cross-sectional area S _p2 of the cross section of the second drop dust generating source search area in the vertical plane of the inverse central axis using the drop dust generating source search area width, respectively; _Computing a first hypothesis oscillation amount E ₁ proportional to the first oscillation source search area central axis vertical cross-sectional area S _p1 , and a second hypothesis oscillation amount E ₂ proportional to the second oscillation source search area central axis vertical cross-sectional area S _p2 . Any one of the first hypothetical oscillation amounts E ₁ and the second calculated in the oscillation amount calculation step is calculated for all combinations of the oscillation amount calculation step and all the drop-fall generation source search areas including the coordinate point p. The coordinate point p is judged to be an abnormal oscillation source of falling sales when the ratios of the assumption oscillation amounts E ₂ are all within a predetermined upper and lower threshold values, and the oscillation calculation step The coordinate point p is not an abnormal oscillation source of falling sales if the ratio between any one of the first household oscillation amounts E ₁ and the second household oscillation amounts E ₂ calculated in is outside the predetermined upper and lower threshold values. At the same time, when the coordinate point p is not included in either the first drop sale source search area and the second drop sale source search area, the determination of an abnormal source of drop sale at the coordinate point p is not performed. In the plume-type, the plume spreading width at the second distance L _d (i _N ) on the plume center axis is defined as the plume center axis in the plume type. The calculated plume spreading width is used as the dropout generating source search region width.

In the representative wind direction derivation step, the representative wind direction WD may be derived as an average value of the measured values of the wind direction in the period T _d (i _t ).

In the representative wind speed derivation step, the representative wind speed WS may be derived as an average value of the measured values of the wind speed in the period T _d (i _t ).

In the representative falling speed derivation step, the representative falling speed V _s may be derived as an average value of the measured values of the falling speed of the falling dust in the period T _d (i _t ).

(2) As a 2nd aspect of this invention, in the searching method of the abnormal oscillation source position of the falling dust of the said 1st aspect, the said center of gravity of the said falling dust generating source search area is made into the horizontal direction of the said wind direction as a horizontal component. And a value V _s / WS obtained by dividing the representative drop rate V _s of the drop sale by the representative wind speed WS as a vertical gradient, and in the plume equation, the central axis of the drop sale source search area is defined as the plume center axis. The second distance on the plume central axis, using the horizontal plume spreading width σ _y at the second distance L _d (i _N ) on the plume central axis as the horizontal component of the width of the falling dust generating source search region. The vertical plume spreading width σ _z in L _d (i _N ) may be used as a vertical component of the width of the falling dust generating source search region.

(3) As a 3rd aspect of this invention, the horizontal plume spreading | diffusion width (s) _y and the perpendicular | vertical plume spreading | diffusion width in the searching method of the abnormal oscillation source position of the falling-out dust of the said 1st form or the said 2nd form σ _z , the distance x from the source on the center axis of the plume, the amount of oscillation Q _P , the representative velocity WS, the constant B and the horizontal plume spreading width σ _y and the plume plume spreading width σ _z Equations (1) and (2) below (where the units are all SI units), which express the sold concentration C (x) at a distance x on the central axis using the range,

(플룸 범위 내) …(1)

(In plume range)… (One)

(플룸 범위 밖) …(2)

(Outside the plumb range)… (2)

May be used as the plume type.

(4) As a third aspect of the present invention, there is provided a method of searching for the abnormal oscillation source location of the drop sold according to the third aspect, of the horizontal plume spreading width σ _y, and the vertical direction of the plume spreading width σ _z, than An ellipse whose length is twice as long and whose length is shorter as 2 times may be a plume cross-sectional shape perpendicular to the plume central axis, and the inside of the ellipse may be within the plume range.

(5) As a 4th aspect of this invention, in the search method of the abnormal oscillation source position of the drop-off sold out in any one of said 1st form-said 4th aspect, the said evaluation is within the said period T _d (i _t ). The method further includes a sediment type classification process for measuring the radiation dose of the falling dust sample collected at the point, and classifying the falling dust for each sold species based on the measured intensity of the radiation dose. The mass of the falling dust of the portion corresponding to any one of the sold out kinds classified in the species sorting step may be set as the falling selling amount M.

According to each of the above forms, it is possible to efficiently and accurately search for the oscillation source of the falling dust whose oscillation amount changes abnormally.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of the plume projected in the horizontal plane which concerns on embodiment of this invention.
It is a figure which shows an example of the plume projected in the perpendicular plane which concerns on embodiment of this invention.
3 is a flowchart for explaining an example of the process of the oscillation source search apparatus according to the embodiment of the present invention.
4 is a diagram illustrating an example of the oscillation source search area according to the embodiment of the present invention.

(Features of the embodiment of the present invention)

First, the characteristic of embodiment of this invention is demonstrated.

The 1st characteristic of embodiment of this invention is the point which can search the oscillation source of a drop sale by measuring the drop sale directly at an evaluation point.

According to a second aspect of the embodiment of the present invention, in the search for the oscillation source of falling dust, the oscillation source search area extending from the evaluation point in the wind direction direction is correlated with the plume expression to determine the oscillation amount in the oscillation source candidate. Information can be obtained.

Specifically, as described above, in the prior art, the handling of the ground surface reflection (α · exp [− (He + z−V _s x / WS) ² / 2σ _z ² ]) in the formula (2) is difficult. It was. For this reason, it was thought that it is difficult to correlate the oscillation source search line extended from an evaluation point to a wind direction with a plume type. However, as a result of the investigation by the present inventors, it has been found that this surface surface problem is a problem because the prior art mainly targets gas or SPM. If the drop is sold out, because due to the falling speed of the particle size, the deposition rate V _d ≒ falling speed V _s, the influence of reflection at the surface can be considered to be small and, α = 0. Therefore, the air diffusion equation (plum type) for the drop-off sold out is as shown in the following equation (4) by substituting alpha = 0 in equation (2).

…(4)

... (4)

Here, when coordinate transformation is performed by the following formula (5), Formula (4) becomes like following formula (6).

…(5)

... (5)

…(6)

... (6)

Here, the coordinate transformation from z to Z by Equation (5) is based on the origin (oscillation source) as the origin, and in the wind direction, at an incidence angle of tan ⁻¹ [V _s (particle drop speed) / WS (wind speed)]. It corresponds to setting the central axis of the sold out plume in the vertical plane, and defining the density with this central axis as the Z axis.

The plume diffusion width σ _y is the standard deviation of the concentration distribution in the y direction. The plume diffusion width σ _z is the standard deviation of the concentration distribution in the z direction. In addition, the normal, «WS V _s, in terms of V _s «WS, z direction may be considered substantially equal to the Z direction. In most cases, the concentration distribution in the y and z directions can be regarded as a normal distribution if there is no influence of reflection on the ground surface. At this time, the concentration values at y = σ _y and Z = σ _z are 60% of the maximum concentration value, whereas the concentration values at y = 2σ _y and Z = 2σ _z are 13% of the maximum concentration value. It is only That is, in the region of y> σ _y and Z> σ _z , the concentration drops rapidly. Therefore, in embodiment of this invention, it is assumed that following formula (7a) and formula (7b) are assumed as a plume formula.

(플룸 범위 내) …(7a)

(In plume range)… (7a)

(플룸 범위 밖) …(7b)

(Outside the plumb range)… (7b)

Here, the meaning of the symbol of Formula (7a) is as follows.

B: proportional constant

In the present method, since the equation (7a) has only a relative value as a problem, an arbitrary value (for example, 1) may be given to the proportional constant B.

In addition, a plume range means the area | region on the side of a center axis rather than the position where the density | concentration when a Gaussian distribution is assumed for the density | concentration distribution of a plume perpendicular direction like Formula (4) shows the value of the standard deviation of concentration distribution. Alternatively, an ellipse in which the longer side of the σ _y and the sigma _z is shorter than the longer axis and the shorter side is shortened to the plume cross-sectional shape may be made within the plume range. In addition, it is good also as a range of the following formula (8) more simply. On the other hand, outside the plume range means an area outside the plume range.

또한

…(8)

Also

... (8)

Here, σ _y and σ _z are functions of the distance L ₀ from the oscillation source and the period Δt _d (σ _y [L ₀ , Δt _d ], σ _z [L ₀ , Δt _d ]). σ _y and σ _z are check or plotted values obtained by fixing Δt _d (which is taken as a reference period), using Pasquill-Gifford, Briggs, or the like described in Non-Patent Document 1 And empirically correct the influence of Δt _d . A method for correcting the influence of Δt _{d in} an empirical formula is to multiply σ _y by ([Δt _d used in actuality / [Δt _d of reference net time]) ^P as σ _y .

Given the sold type and the sold particle diameter, the particle drop velocity V _s is determined as the end velocity, so the dropping amount M (x) is obtained by multiplying the concentration C (x) by the particle drop velocity V _s . , Can be expressed by the formula (9b).

(플룸 범위 내) …(9a)

(In plume range)… (9a)

(플룸 범위 밖) …(9b)

(Outside the plumb range)… (9b)

In the formula (9a), under the condition of a constant wind speed, the local drop-off amount M (x) within the plume range is determined only by the oscillation amount Q _P and the plume diffusion width σ _y and σ _z . In addition, the value of the plume spreading width (sigma) _y and (sigma) _z can be expressed as a function of x and Gippford described in Nonpatent literature 1 as a function of x and a gaseous-phase condition, for example. Therefore, under constant oscillation source conditions, and also under constant weather conditions, the amount of the drop sale amount M (x) at a specific evaluation point can be expressed only by the distance x from the specific oscillation source.

Next, using Formula (9), the existence range of an oscillation source in a specific evaluation point is considered.

1 shows from two oscillation sources i _o1 , i _o2 present at the position x '= L ₀ on the global coordinate system x', y '(surface) in a horizontal plane with a specific evaluation point i _M as origin O, sweating plume α (i _o1) to the evaluation points _M i and the same horizontal plane and a view projected onto the α (i _o2). At this time, the wind direction WD is the negative direction of x '. The positions of the plumes α (i _o1 ) and α (i _o2 ) are at x '= 0, where the respective center axes 10a and 10b coincide with the ground surface, and the horizontal ends of the plumes [plumb α (i _{In o1} ), the plumes α (i _o1 ) and α (i _o2 ) are arranged so that the negative end of y 'and the positive end of y' in the plume α (i _o2 ) pass through the origin O. From the oscillation sources i _o1 and i _o2 where the arrangement of the plumes α (i _o1 ) and α (i _o2 ) is set to x = L ₀ , the plumes α (i _o1 ) and α (i _o2 ) are the evaluation points i _M The location of the limit that can be reached. That is, the position of the oscillation source i _o1 is the limit position on the positive side of y ', and the position of the oscillation source i _o2 is the limit position on the negative side of y'.

The spreading width σ _y at x '= 0 of the plumes α (i _o1 ) and α (i _o2 ) is σ _y (L ₀ ). Therefore, the half width of the distance between the oscillation sources i _o1 and i _o2 in x '= L ₀ is σ _y (L ₀ ), that is, x' = of the plumes α (i _o1 ) and α (i _o2 ). It corresponds to the diffusion width σ _y at zero. Here, when estimating the positions of the oscillation sources i _o1 and i _o2 when the drop sale is measured at the evaluation point i _M , the ranges in which the oscillation sources i _o1 and i _o2 may exist in the horizontal plane are origin O and is the oscillation source i _o1 point line and the origin O and source oscillation i _o2 point line region γ (i _M) sandwiched by passing through the passing through of the (a region that is shown by oblique lines). This region γ (i _M ) is the oscillation source search region.

However, the value of the oscillation source i _o1, x '= L ₀ to position i _o2 may be any. Therefore, at the arbitrary x 'position, the half width of the range in the y' direction of the oscillation sources i _o1 and i _o2 that can reach the evaluation point i _M is always? _Y (x '). That is, the half-width in the y 'direction of the oscillation source search region γ (i _M ) is, for example, the same as that of σ _y on the same horizontal plane as the oscillation source in the plume equation of Expression (6). Therefore, that the oscillation source search in the horizontal surface area γ (i _M) is expressed as a function of distance only from the evaluation point i _M on the evaluation point i of the center shaft 11 extending in the upwind direction of the representative direction of the wind from the _M Can be set by the search area width.

FIG. 2 shows an evaluation point i from two oscillation sources i _o3 , i _o4 , which exist at the position of x '= L ₀ on the global coordinate system x', z in a vertical plane with the specific evaluation point i _M as the origin O; sweating plume α (i _o3) in the _M and the same vertical plane, and a view projected onto the α (i _o4).

Basically, in the same manner as described with reference to FIG. 1, the oscillation source search range γ (i _M ) is set. At this time, the width of the oscillation source search range γ (i _M ) is represented by the spreading width σ _z (x ′).

In addition, since the falling sales fall, in the vertical section, the central axes 10a, 10b of the plume α [i _o3 , α (i _o4 ) and the central axis 11 of the oscillation source search region γ (i _M ), _{^{θ (= tan -1 (V s}} / WS)] is inclined by an angle. Therefore, the upwind point of the direction of the evaluation point _M i, i _o3 oscillation source, the evaluation point i _M i from drop sold to reach _o4 What can be done is limited to what oscillated in the area | region of one part of the area | region extended in the wind direction from evaluation point i _M. In this way, the source search area gamma (i _M ) is extended in the wind direction from evaluation point i _M. In the search method of the oscillation source, the limit of the range of the distance in the wind direction is a thinking method that does not exist in the conventional method, and the present method can define the oscillation source search area gamma (i _M ). Advantageous over the conventional method.

The simple and quantitative representation of the oscillation source search region γ (i _M ) modified from the plume equation of the above-mentioned drop-off amount is not feasible with a plume expression based on a conventional gas or SPM. the sold-out to drop, falling speed V _s is the first time made possible by the relatively large series of insight performed after the target to.

In addition, this invention is not limited only to using the plume formula of Formula (9). For example, if accurate measurement can be made in advance so that the influence of the surface reflections can be accurately expressed, the correction of the sigma _z term in the equation (9) is appropriately applied based on the plume expression with the surface reflections left. You may also

The third characteristic of the embodiment of the present invention is that the oscillation source and the oscillation amount do not necessarily need to be assumed in advance. Since the oscillation source in reality is often not known in advance in both the position and the oscillation amount, the method of the embodiment of the present invention is advantageous in that the oscillation source can be searched based on the reality.

The 4th characteristic of embodiment of this invention is the point which can specify an abnormal oscillation source. In the method of the embodiment of the present invention, the main oscillation in the time period is performed every acquisition cycle of the positive measured value of the drop sale, or every time for several consecutive cycles of the acquisition cycle of the positive measured value of the drop sale. You can specify a circle. Therefore, this can be grasped | ascertained if it is an abnormal oscillation source which fluctuates on the time scale more than several cycles of the acquisition cycle of the measured value of the falling-off quantity. In addition, the number of evaluation points required when specifying the abnormal oscillation source is sufficiently smaller than the number of potential oscillation sources.

The fifth feature of the embodiment of the present invention is that the falling dust collected at the evaluation point is classified into radioactive dropping dust or non-radioactive dropping dust so that the abnormal oscillation source of the radioactive dropping dust is not approached to the radioactive oscillating source. It is the point which can be specified using the falling-sold measurement data from a place.

EMBODIMENT OF THE INVENTION Below, preferred embodiment of this invention is described in detail, referring drawings. In addition, in this specification and drawing, the description which overlaps by attaching | subjecting the same code | symbol about the component which has a substantially same functional structure is abbreviate | omitted.

(1st embodiment)

First, the first embodiment of the present invention will be described.

The drop sale amount (mass of drop sale) is measured for each period Δt _d by the drop sale amount measuring means (apparatus), and the measured value of the drop sale amount is output for each period Δt _d . Let t _d (i _t ) be the time at which the drop out amount is output from the drop out amount measurement means. The time (period) from the time t _d (i _t -1) to the time t _d (i _t ) is defined as "period T _d (i _t )". Here, i _t is an integer which increments by 1, making 0 the time which started the measurement of falling out sales. In the present embodiment, the source of the falling dust in each "period T _d (i _t )" is specified, and an oscillation source having a time scale (that is, oscillation duration time) equal to or greater than the period Δt _d is used as a search target. do.

Further, in the three-dimensional area where the oscillation source can be searched, a rectangular coordinate system of x, y, and z is set, and n _x , n _y , n _z coordinate components are provided on each coordinate axis, respectively. It is assumed that the three-dimensional space is represented by n _x x n _y x n _z coordinate points p. Here, the coordinate point p represents a coordinate point where each coordinate component is i _x th, i _y th and i _z th, respectively. The position of each coordinate point is written Sc (i _x , i _y , i _z ) as a position vector from the origin using the order i _x , i _y , i _z of the coordinate components on each coordinate axis. At each coordinate point p, any one of "oscillation source", "not oscillation source", and "undecided" is set as the oscillation source determination mode.

An example of the process (oscillation source search processing) of the oscillation source search apparatus at the time of searching for an oscillation source is demonstrated using the flowchart of FIG. The oscillation source search apparatus is realized by using, for example, a computing device such as a CPU, a memory, a hard disc drive (HDD), and an information processing device (for example, a commercial personal computer (PC)) equipped with various interfaces. do. For example, the flowchart of FIG. 3 is translated into a computer program executable using a programming language such as C language, and stored in advance in an HDD or the like. At the time of execution of the oscillation source search processing in the information processing apparatus, the executable computer program stored in the HDD or the like is read and started by a computing device such as a CPU, and the CPU based on the instruction of the executable computer program is executed. It is realized by sequentially executing computing devices such as the above. The start timing of the oscillation source search process may be started by a hand input or may be automatically started periodically. As described above, the oscillation source search apparatus of the present embodiment searches for the oscillation source of the dropout sold out in the "period T _d (i _t )" at a certain time.

In the oscillation source search apparatus, necessary input information such as positional information such as an evaluation point and a coordinate point, measured values such as a drop sale amount, a wind direction, and a wind speed, and an analysis value relating to the type of sold out may include a keyboard connected to an information processing device, Using the console screen, etc., it can input in advance by manpower. The input information entered is stored in the HDD or the like and appropriately read in accordance with the progress of the oscillation source search processing.

In the oscillation source search apparatus, calculation results such as abnormal oscillation source determination results and oscillation amounts for the calculated specific coordinate points can be stored in the HDD or the like and displayed on the console screen or the like.

In addition, even if part or all of the process of the said oscillation source search apparatus is replaced by other means, such as a hand calculation, there is no problem at all.

First, a 1st process is demonstrated.

In step S101, the oscillation source search apparatus initializes the oscillation source determination mode to "undecided" at all coordinate points p.

Next, in step S102, the oscillation source search apparatus is the "representative wind speed WS, the representative wind direction WD, and all evaluation points (evaluation point is distinguished by number i) in" period T _d (i _t ). " The falling-off amount M (i) at n _M ≥ i ≥ 1 and the representative falling speed V _s ′ of the falling-off particles are set (input). In this embodiment, for example, in this step S102, a sold-out amount setting process, a representative wind direction derivation process, a representative wind speed derivation process, and a representative fall speed derivation process are performed.

Here, the falling-off amount M (i) can be measured, for example, by setting the period Δt _d as 10 minutes, for example, using the continuous falling-off system described in Patent Document 6. Wind direction and wind speed, for example, by using a propeller type wind anemometer commercially available, period Δt _d than the short period Δt _wint may be a value measured in (e.g. cycles per second). The spatial resolution of the wind direction is, for example, at 1 ° intervals. The representative wind direction WD and the representative wind speed WS can use the average value of the "wind direction, the measured value of a wind speed" in "period T _d ", respectively, for example. Alternatively, as the representative wind direction WD and the representative wind speed WS, the instantaneous measured values of the wind direction and the wind speed may be layered, and a layered value for generating a mode value in the "period T _d " may be used.

The wind vane and anemometer are installed in the vicinity of the dropout management point i. Here, "the vicinity of the descent-sold management point i" should just be a range which shows a high correlation with the wind direction and the wind speed in the air above the descent-sold out management point i, for example, descent-sold management point i It can be a horizontal distance within 1 km from. In an area where the topography is monotonous and the wind direction and wind speed distribution are small, the horizontal distance above this may be near the dropout control point i. In addition, the height of the measurement point of wind direction and wind speed can employ | adopt 10 m from the ground surface which is the measurement height recommended by the Meteorological Agency, for example. When the height of the assumed oscillation source is sufficiently higher than 10 m, for example, the height between the ground surface and the oscillation source height may be the height of the measurement point.

It may also be employed as the "period T _{d (t} i)" by using the drop sold samples collected in the rating point, the falling speed V _s representative of the measured average drop velocity, and drop it on a sold particle. As a measuring method of the falling velocity of a falling-off sample, the following method is mentioned, for example. In other words, by emitting a drop sold sample from the upper side of the hermetically sealed container, and each measuring the amount of time that the individual drop sold particles reach the container bottom, and dividing the falling away by falling time, a representative drop speed V _s of the drop sold particles You can get it. In order to detect that the individual falling-off particles have reached the bottom of the container, the bottom of the container is irradiated continuously with sheet-shaped laser light in the horizontal direction, and the scattered light generated when the falling-off is passed through this laser light is lighted. A method such as detection by a detector can be employed.

As a method for calculating the representative drop rate V _s from the drop speeds of the individual drop-off particles, the drop time corresponding to the time when 50% of the drop-out particles in the number of all drop-out particles reaches the bottom of the container is sold out. a falling speed of the drop sold particles according to the representative of the falling speed V _s of the particles can be employed. Alternatively, in the case where the approximate density and shape of the drop sale is known in advance, the representative drop rate V _s of the drop sale particles can be calculated by simply measuring the particle size distribution of the drop sale sample. As a method to calculate the fall speed V _s representative of the descent sold particles from the particle size of the drop sold, for example, it can be used on the following Stokes' end of the speed of the formula (10).

…(10)

... (10)

Here, the meaning of the symbol of Formula (10) is as follows (all are SI units).

g: gravity acceleration [m / s ² ]

D _p : Particle diameter [m]

ρ _P , ρ _f : Density of particles and fluids [㎏ / ㎥]

C _R : Resistance coefficient [-] (various checks are indicated depending on particle shape)

Next, in step S103, the oscillation source search apparatus calculates the position in the horizontal plane (for example, ground elevation 1.5m) of all the evaluation points i as position vector P (i) which shows the position from the origin of the said coordinate system. do.

In step S104, the oscillation source search apparatus sets the oscillation source search area gamma (i) for each evaluation point i at every evaluation point i. 4 is a diagram illustrating an example of the oscillation source search region γ (i). An example of a method of setting the oscillation source search region γ (i) will be described with reference to FIG. 4. In this embodiment, for example, in this step S104, the dropout generation source search area setting step is executed.

In Figure 4, γ _(M i) is the oscillation source search area γ (i _M) indicated by digesting each of the coordinate components according to Figs. 2 and 3, a graphical representation in the drawings of sheets 1 by the isometric projection. In FIG. 4, two evaluation points i _M and i _N are provided on the absolute coordinates (x ', y', z), and these evaluation points i _M and i _N are used as starting points, and in the wind direction of the representative wind direction WD. At the elevation angle [theta] [= tan ^-1 (V _s / WS)], the central axes of the oscillation source search areas gamma (i _M ) and gamma (i _N ) are set. The oscillation source search area is set to form an elliptical cross section around the center axis with a width of 2σ _y in the horizontal direction and 2σ _z in the vertical direction.

Next, a 2nd process and a 3rd process are demonstrated. In the second step and the third step, the determination of the oscillation source is performed at the specific evaluation point i (= i _M ) at the specific coordinate point p (the oscillation source determination mode is set to either one). If necessary, similar evaluation is performed by changing the evaluation point i and the coordinate point p.

In the second step, first, in step S105, the oscillation source search apparatus selects an unselected evaluation point i as the first evaluation point i _M.

Next, in step S106, the oscillation source search apparatus selects an unselected thing among the coordinate points p.

Next, in step S107, the oscillation source search apparatus determines the position vector Sc (i _x , i _y , i _z ) of the coordinate point p. Coordinate position of point p vector Sc is, to the origin of the coordinate axis as the starting point and each coordinate component is i _x th, i _y-th, points (that is, p points) serving as i _z second axis dividing point of each of the end point Set it. Here, the first oscillation source search area γ (i _M ) with respect to the first evaluation point i _M is referred to as the first oscillation source search area γ (i _M ), and the second oscillation source search area with respect to the second evaluation point i _N is described. γ (i _N ) is called the second oscillation source search region γ (i _N ).

Next, in step S108, the oscillation source search device selects an unselected evaluation point i as the second evaluation point i _N.

Next, in step S109, the oscillation source search apparatus determines whether the first evaluation point i _M selected in step S105 and the second evaluation point i _N selected in step S108 are the same positions. As a result of this determination, when the 1st evaluation point i _M and the 2nd evaluation point i _N are in a different position, it progresses to step S110. On the other hand, when the 1st evaluation point i _M and the 2nd evaluation point i _N are the same position, step S110-S118 are abbreviate | omitted and it progresses to step S119 mentioned later.

Proceeding to step S110, the oscillation source search apparatus includes the coordinate point p selected in step S106 in both the first oscillation source search region γ (i _M ) and the second oscillation source search region γ (i _N ), In addition, it is determined whether or not the oscillation source determination mode of the coordinate point p selected in step S106 satisfies an oscillation source determination condition of a mode other than "not an oscillation source".

As a result of this determination, when the oscillation source determination condition is satisfied (all), the coordinate point p selected in step S106 may be an oscillation source. This state of satisfying the oscillation source determination condition is shown in Fig. 4 in the common region 41 (illustrated by diagonal lines) of the first oscillation source search region γ (i _M ) and the second oscillation source search region γ (i _N ). Area) corresponds to a state where the coordinate point p exists. In this way, when the oscillation source determination condition is satisfied, the process proceeds to step S111. On the other hand, when an oscillation source determination condition is not satisfied, step S111-S118 are abbreviate | omitted and it progresses to step S119 mentioned later.

Proceeding to step S111, the oscillation source search device steps the same as the first (shortest) distance L _d (i _M ) between the coordinate point p selected in step S106 and the first evaluation point i _M selected in step S105. The second (shortest) distance L _d (i _N ) between the coordinate point p selected in S106 and the second evaluation point i _N selected in step S108 is respectively calculated. In this embodiment, for example, the distance calculation step is executed in this step S108.

The first distance L _d (i _M ) between the coordinate point p and the first evaluation point i _M is, for example, the end point of the vector P (i _M ) of the first evaluation point i _M and the position vector of the coordinate point p. It is calculated as the norm of the vector connecting the end points of Sc to each other. The same applies to the calculation method of the second distance L _d (i _N ) between the coordinate point p and the second evaluation point i _N.

Next, in step S112, the oscillation source search apparatus includes the first central axis vertical cross-sectional area S _p1 of the first oscillation source search region γ (i _M ) with respect to the first evaluation point i _M at the coordinate point p. , The second central axis vertical cross-sectional area S _p2 of the second oscillation source search region γ (i _N ) relating to the second evaluation point i _N at the coordinate point p is calculated. First oscillation source search area γ (i _M) first center axis perpendicular to the cross-sectional area S _p1 and the second oscillation source search area γ second central axis method of calculating a vertical cross-sectional area S _p2 of (i _N) of the, e.g. The cross-sectional area is defined as the area of the ellipse in which the larger value is set as the major axis length and the larger value as the minor axis is used as the major axis length among the diffusion widths σ _y [L _d ] and σ _z [L _d ]. It can be calculated by calculating. In this embodiment, this cross-sectional area calculation process is implement | achieved, for example in this step S112.

Next, in step S113, the oscillation source search apparatus estimates from the "first hypothetical oscillation amount E ₁ at the coordinate point p selected in step S106" estimated from the first evaluation point i _M and the second evaluation point i _N. The "second assumption oscillation amount E ₂ at the coordinate point p selected in step S106" is calculated. In this embodiment, for example, this oscillation amount calculating step is executed in step S113. The first assumption oscillation amount E ₁ is calculated using, for example, equation (11a), and the second assumption oscillation amount E ₂ is calculated, for example, using equation (11b).

…(11a)

... (11a)

…(11b)

... (11b)

In Formulas (11a) and (11b), B ₁ is a coefficient. Formulas (11a) and (11b) correspond to that in the general plume, the concentration at the local is proportional to the amount of generation at the source and inversely proportional to the plume cross-sectional area at the local. In other words, if the coordinate point p selected in step S106 is the oscillation source, the concentration inversely proportional to the plume cross-sectional area at the first evaluation point i _M and the second evaluation point i _N is detected. Thus, the amount of generation at the source will be inversely proportional to the plume cross-sectional area at the first evaluation point i _M and the second evaluation point i _N.

B ₁ of formulas (11a) and (11b) is a coefficient that must be changed by a number of parameters, such as weather conditions. However, as described below, in the present embodiment, only the ratio of the first assumption oscillation amount E ₁ and the second assumption oscillation amount E ₂ is used in the determination of the oscillation source. Further, since the first home oscillation amount E ₁ and E ₂ is the amount of oscillation the second home, based on a calculation of data in the same time, the weather conditions that the assumption is common. Thus, as In a simple way to this embodiment, it is possible to set the B ₁ as a constant.

In the third step, first, in step S114, the oscillation source search unit is configured to calculate the ratio R of the first home oscillation amount E ₁ and E _2, the second home oscillating amount. E ₁ / E ₂ may be sufficient as the ratio R of 1st home oscillation amount E ₁ and 2nd home oscillation amount E ₂ , or E ₂ / E ₁ may be sufficient as it.

Next, in step S115, the oscillation source search apparatus determines whether the coordinate point p selected in step S106 is an oscillation source. Specifically, the oscillation source search apparatus determines whether the ratio R between the first household oscillation amount E ₁ and the second household oscillation amount E ₂ is within a range of a preset upper and lower threshold value (R _max ≧ R ≥ R _min ). do. In this embodiment, for example, in step S110 and step S115, an oscillation source determination process is performed. As a result of this determination, if the ratio R between the first hypothetical oscillation amount E ₁ and the second hypothetical oscillation amount E ₂ is within a range of a preset upper and lower threshold value, the coordinate point p selected in step S106 is determined as "oscillation source". . On the other hand, if the ratio R between the first assumption oscillation amount E ₁ and the second assumption oscillation amount E ₂ is outside the range of a preset upper and lower threshold value, the coordinate point p selected in step S106 is determined to be "not an oscillation source".

1 should be included in the range between the upper and lower thresholds of the ratio R of the first hypothetical oscillation amount E ₁ and the second hypothetical oscillation amount E ₂ , but a method of setting the upper and lower threshold values is required for abnormal oscillation source determination. What is necessary is just to set suitably according to the precision to make. That is, if it intends to cover the abnormal oscillation source which exists even a little possibility, what is necessary is just to set a wide range of upper and lower thresholds (for example, setting a lower limit threshold value of 0.1 and an upper limit threshold value of 10). Alternatively, if it is desired to extract only the point where the possibility of abnormal oscillation is extremely high, the upper and lower threshold ranges may be narrowly set (for example, the lower threshold is set to 0.8 and the upper threshold is set to 1.2).

The basis of this determination method is as follows. Time-scale variation amount of the oscillation from the period Δt _d or more abnormal oscillation source, by definition, "duration T _{d (t} i)" within a sufficiently small. Therefore, as long as the amount of oscillation is searched for a large oscillator, that is, a main oscillator, as compared with other oscillators, the drop-off sold out from the main oscillator can be reached during the period "T _d (i _t )". It is considered to be dominant in the evaluation point i. At this time, if there are a plurality of evaluation points i that can be reached during the "period T _d (i _t )", the amount of falling sales observed at these evaluation points i is an oscillation source (coordinate point p) and each evaluation point i. Depending on the function of the distance between (ie, plume), they will exhibit a constant ratio to each other. Therefore, the coordinate point p which satisfies this condition has high possibility as a main oscillation source. Therefore, when the ratio R of the 1st hypothetical oscillation amount E ₁ and the 2nd hypothetical oscillation amount E ₂ is within the range of a preset upper and lower threshold value, it is determined that the coordinate point p selected in step S106 is "oscillation source".

On the other hand, if the ratio of the amount of falling sales observed at the evaluation point i is significantly different from the value calculated from the plume equation, the coordinate point p selected in step S106 is a plurality of evaluation points i in the "period T _d (i _t )". Even if the coordinate point p existing at the position where the falling-out can reach, it is likely that it is a false oscillation source. Therefore, when the ratio R between the first home oscillation amount E ₁ and the second home oscillation amount E _{2 is out} of the predetermined upper and lower threshold values, it is determined that the coordinate point p selected in step S106 is not the "oscillation source".

As a result of this determination, when the coordinate point p selected in step S106 is not an oscillation source, it progresses to step S116. On the other hand, when the coordinate point p selected in step S106 is an oscillation source, it progresses to step S117 mentioned later.

Proceeding to step S116, the oscillation source search apparatus sets the oscillation source determination mode of the coordinate point p selected in step S106 to "not oscillation source." The process then proceeds to step S119 described later.

On the other hand, when it progresses to step S117, the oscillation source search apparatus sets the oscillation source determination mode of the coordinate point p selected in step S106 to "oscillation source." In this embodiment, for example, in this step S117, the oscillation source setting step is executed.

Next, in step S118, the oscillation source search apparatus calculates the estimated oscillation amount in the coordinate point p determined as "oscillation source." The estimated oscillation amount can be, for example, an average value of all hypothetical oscillation amounts E used in the oscillation source determination (step S115) at the coordinate point p determined as the "oscillation source". The flow then advances to step S119.

Proceeding to step S119, the oscillation source search apparatus determines whether all evaluation points i have been selected. As a result of this determination, when all the evaluation points i have not been selected, it returns to step S108. On the other hand, when all evaluation points i are selected, it progresses to step S120.

Proceeding to step S120, the oscillation source search apparatus determines whether all coordinate points p have been selected. As a result of this determination, when all the coordinate points p are not selected, it returns to step S106. On the other hand, when all the coordinate points p are selected, it progresses to step S121.

Proceeding to step S121, the oscillation source search apparatus determines whether all evaluation points i have been selected. As a result of this determination, when all the evaluation points i have not been selected, it returns to step S105. On the other hand, when all the evaluation points i are selected, it progresses to step S122.

Proceeding to step S122, the oscillation source search apparatus displays the position of the oscillation source and the estimated oscillation amount in the oscillation source. Then, the process according to the flowchart of FIG. 3 is terminated. In addition, it may not be determined that all the coordinate points p are oscillation sources. In this case, in step S122, the oscillation source search device displays the effect. In addition, although all the coordinate points p and all evaluation points i _M and i _N are selected here, it does not necessarily need to be like this, You may make them select them. In this case, at the coordinate point p which is not the target of the oscillation source determination (the determination of step S115), "undecided" of the initial value remains as the oscillation source determination mode. In addition, you may complete a process at the time of obtaining an oscillation source.

As described above, the evaluation from the point p to the source of the search area that extends in the upwind direction, by introducing a way of thinking of a flat rumsik, the oscillation at the location and source of the source of the time scale period or more Δt _d, drop sold It is possible to accurately specify the quantity. Therefore, by measuring the drop-out sales at a few evaluation points, it becomes possible to efficiently and accurately search for the oscillation source including the abnormal oscillation source.

(Second Embodiment)

Next, a second embodiment of the present invention will be described.

When it is known that the oscillation source is limited to the height near the ground surface, the oscillation source search area is set not in the three-dimensional area as in the first embodiment but in the horizontal plane (in the two-dimensional area), The process of searching for the source of oscillation can be simplified.

Specifically, in step S104 of FIG. 3, the oscillation source search apparatus determines the inclination in the vertical direction of the central axis of the first oscillation source search region γ (i _M ) and the second oscillation source search region γ (i _N ). omitted and screen (the above-described elevation angle θ of 0 ° to), the first oscillation source search area γ (i _M) and a second oscillation source search area γ _(N i) a 2-D.

The position vectors P and Sc in steps S103 and S107 are also two-dimensional vectors in which the vertical components are omitted.

However, even when the first oscillation source search area γ (i _M ) and the second oscillation source search area γ (i _N ) are two-dimensional in this manner, when calculating the amount of oscillation at the coordinate point p, the sold-out plume It is necessary to consider the effect of diffusion in the vertical direction. For this reason, in step S112, it is necessary to calculate the 1st central axis vertical cross-sectional area S _p1 of a 1st oscillation source search area, and the 2nd central axis vertical cross-sectional area S _p2 of a 2nd oscillation source search area. The first central axis vertical cross-sectional area S _p1 of the first oscillation source search region and the second central axis vertical cross-sectional area S _p2 of the second oscillation source search region are calculated from the previously calculated " first distance L _d (i _M ) _Quot ;, the horizontal diffusion width? _Y [L _d ] of the drop-out particles at the distance L _d (i _N ) can be set to the radius of the circle. Or "the first distance L corresponding to the" diffusion width σ _y [L _d ] of the horizontal direction "of the drop-off sold particles at the first distance L _d (i _M ) and the second distance L _d (i _N ). _d (i _M), the second distance L _d (i _N) by using the "in the vertical direction of spread width σ _z [L _d]" of the drop sold particles in, a major axis and a minor axis 2 × σ _y or 2 × It is good also as a cross section of an ellipse set to (sigma) _Z.

By such handling, the calculation load required for searching for the oscillation source can be reduced.

(Third Embodiment)

Next, a third embodiment of the present invention will be described.

The radiation of the falling dust collected at the evaluation point is measured, and based on the intensity, the individual falling dust particles (or samples) or the whole falling dust particles (samples) are classified as radioactive drop dust or non-radioactive drop dust. In addition, it is possible to search for an abnormal oscillation source of the radioactive dropout (or nonradioactive dropout) targeting only the radioactive dropout sale (or the nonradioactive dropout sale).

A well-known method can be used for the measuring method of the radiation intensity of falling fallout. For example, the method described in patent documents 7-9 can be used.

In classification of drop sold sample based on the radiation intensity, for example, the period T _{d (t} i) [time t _d of time (duration) until time t _{d (t} i) from _(t i -1)] Each falling dust particle in the sample collected at each evaluation point is separated by one, and each radiation intensity is measured. When the radiation intensity is above a predetermined threshold value, the falling sold-out particles having the radiation intensity are radioactive falling dust. In addition, it can classify other than non-radioactive falling-out. Since the mass of the whole sample is measured as a drop sale amount, the ratio of the number of radioactive drops sold to the mass of the whole sample (= [number of radioactive drops sold ÷ (number of radioactive drops sold + number of non-radioactive drops sold)) ]) Can be used as the mass of the radioactive dripping stock in this sample. Alternatively, the radiation intensity of the entire sample of the collected specific drop-off particles is measured, and when the radiation intensity is greater than or equal to a predetermined threshold value, the mass of the entire sample is defined as the mass of the radioactive drop-off particulate, and in other cases, the sample The mass of the whole may be made into the mass of a non-radioactive fall-out sold-out. In step S102 of FIG. 3, the mass (or the mass of non-radioactive falling dust) of the radioactive falling dust obtained in this way is set as the falling-off amount M (i). And an "oscillation source", "not an oscillation source", and "undetermination" are set for the radioactive drop sold-out (or non-radioactive drop sold-out).

By such handling, for example, an abnormal oscillation source of radioactive fallout can be specified using the dropout measurement data from a remote place without approaching the radioactive oscillation source. In addition, about which radioactive dropout and non-radioactive fallout are made into the search target of an oscillation source, For example, before starting the flowchart of FIG. 3, using the keyboard, console screen, etc. which were connected to the information processing apparatus, It can be set (input) by manpower in advance.

In addition, embodiment of this invention demonstrated above can be implement | achieved by a computer executing a program. The computer-readable recording medium on which the program is recorded, and computer program products such as the program, can also be applied as an embodiment of the present invention. As the recording medium, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

As mentioned above, although preferred embodiment of this invention was described and demonstrated, these are illustrations of the invention to the last and are not to be considered limited at all, Addition, deletion, substitution, and other change are a range which does not deviate from the meaning of this invention. It is possible. That is, this invention is not limited only by embodiment mentioned above.

INDUSTRIAL APPLICABILITY The present invention can be broadly applied to a method for searching for an oscillation source of a drop sold-out in which the oscillation amount (rate of occurrence of drop-out in the oscillation source) fluctuates abnormally in a nuclear power plant or the like, Efficient and accurate search.

i: evaluation point
p: oscillator (coordinate)
WD: Wind Direction
α: plume of falling sales
γ: oscillation source search range
10: central axis of plume
11: center axis of oscillation source search area
41: common area between oscillator source search areas

Claims (10)

Period to the second time _t i of every Δt _d to the time t _{d (t} i), each of the other at least two evaluation points, the time t _d t _d time _(t i) from (i _t -1) A sold out amount setting step of collecting falling sales in a period T _d (i _t ), which is a period up to, and obtaining a measured value of the falling out sales amount M per unit time;
Wherein in each of the vicinity of the respective evaluation points, the period T _d (i _t) representative of the wind direction in the cycle continuously measures the wind direction in a short period Δt _wint than Δt _d in, and in the period T _d (i _t) Representative wind direction derivation process to derive WD,
In each of the vicinity of the respective evaluation points, the period T _d measured by the cycle continuously wind a Δt _{wi nt} in (i _t), and deriving the representative wind speed WS in the period T _d (i _t) Representative wind speed derivation process,
In each of the vicinity of the respective evaluation points, the period T _d (i _t) representative of the said period T _d (i _t) the measurement period the falling speed of the drop sold successively with Δt _{wi nt,} and the A representative drop speed deriving process for deriving a drop speed V _s ,
It has a center axis | shaft extended as the wind direction of the said representative wind direction WD, and makes the fall-out sales source search area width around the said center axis | shaft, and sets it as the starting point at the 1st evaluation point i _M , and sells it to the perpendicular direction from the said center axis | shaft. The first drop-fall generation source search area gamma (i _M ) having the range of the distance to the source search area width as an area, and the second evaluation point i _N different from the first evaluation point i _M as starting points. The area having the central axis extending in the wind direction of the wind direction WD, and at the same time forming the width of the falling dust generating source search area around the central axis, the area of the distance from the central axis to the width of the falling dust generating source search area in the vertical direction as an area. A dropping dust source source search region setting step of setting a second drop dust generating source search region γ (i _N ) to be performed;
The first distance L between the coordinate point p included in both of the first drop-fall generating source search region γ (i _M ) and the second drop-fall generating source search region γ (i _N ) and the first evaluation point i _M. a distance calculation step of calculating _d (i _M ) and a second distance L _d (i _N ) between the coordinate point p and the second evaluation point i _N ;
A first oscillation source search area central axis vertical cross-sectional area S _p1 of a cross-sectional area of the first drop dust generation source search area in a vertical plane of the central axis of the first drop dust generating source search area including the coordinate point p, and the coordinate point p A second oscillation source search area center axis vertical cross-sectional area S _p2 of the cross-sectional area of the second drop sale source search area in the vertical plane of the central axis of the second drop sale source search area including a; Cross-sectional area calculation step
Calculate a first hypothesis oscillation amount E ₁ proportional to the first oscillation source search area central axis vertical cross-sectional area S _p1 , and a second hypothesis oscillation amount E ₂ proportional to the second oscillation source search area central axis vertical cross-sectional area S _p2 Oscillation quantity calculation process to do,
With respect to all combinations of all the falling dust generating source search areas including the coordinate point p, the one of the first assumption oscillation amount E ₁ and the second assumption oscillation amount E ₂ calculated in the oscillation amount calculating step is calculated. If all of the ratios are within a range of a predetermined upper and lower threshold value, the coordinate point p is judged to be an abnormal oscillation source of falling dust, and on the other hand, any one of the first assumption oscillation amounts E ₁ calculated in the oscillation amount calculating step. If the ratio of the second hypothesis oscillation amount E ₂ is outside the range of a predetermined upper and lower threshold, it is determined that the coordinate point p is not an abnormal oscillation source of the drop sale, and the coordinate point p searches for the first drop sale source. An oscillation source plate which does not determine an abnormal oscillation source of the falling sales at the coordinate point p, when it is not included in either the area or the second falling sales source search area. A step,
In the plume formula, the plume spreading width at the second distance L _d (i _N ) on the plume center axis is calculated using the center of gravity of the falling dust generating source search region as the plume center axis, and the calculated plume spreading is calculated. The width | variety is used as the said falling-sold out source search area width | variety, The abnormality oscillation source position search method of falling-sold out. The said representative wind direction derivation process WHEREIN: The abnormal wind fall fall-out of the said representative wind direction WD is derived as an average value of the measured value of the said wind direction in the said period T _d (i _t ). How to navigate the source location. 2. The abnormality in falling sales of claim 1, wherein in the representative wind speed derivation step, the representative wind speed WS is derived as an average value of the measured value of the wind speed in the period T _d (i _t ). How to navigate the source location. Claim that according to one of the preceding claims, in the representative falling speed derivation process, which is derived as the mean value of the representative falling speed V _s, the period T _d (i _t) the drop in the drop measurements of speed of the sold-out of the A method for searching for an abnormal oscillation source position for falling sold out. The central axis of the descent dust generating source search region is a horizontal component of the wind direction, and the value V _s / WS obtained by dividing the representative falling velocity V _s of the dripping _dust by the representative wind speed WS is vertical. As a gradient,
In the flat rumsik, the central axis the drop sold source search area in the plume central axis, said second distance L _d (i _N) and the horizontal direction of the plume the lower the spreading width σ _y in on the plume center axis The vertical direction plume spreading width σ _z at the second distance L _d (i _N ) on the plume center axis is used as a horizontal component of the width of the source of dust source search area, and is used as a vertical component of the width of the falling dust source search area. A method for searching for an abnormal oscillation source position of falling out, characterized in that it is used. 2. The horizontal plume spreading width σ _y , the vertical plume spreading width σ _z , the distance x from the source on the plume central axis, the oscillation amount Q _P , the representative velocity WS, the constant B, and the horizontal The following equations (1) and (2) expressing the sold concentration C (x) at a distance x on the central axis using a plume range defined using the directional plume spreading width σ _y and the vertical directional plume spreading width σ _z . (Unit is all SI unit),

(In plume range)… (One)

(Outside the plumb range)… (2)
It is used as the said plume type, The search method of the abnormal oscillation source position of falling out. The ellipse according to claim 6, wherein an ellipse in which the longer side is set to two times and the shorter side is set to the shorter of the horizontal plume spreading width σ _y and the vertical plume spreading width σ _z . A plumbing cross-sectional shape perpendicular to the central axis, wherein the inside of the ellipse is within the plume range. The horizontal plume spreading width σ _y , the vertical plume spreading width σ _z , the distance x from the source on the plume central axis, the oscillation amount Q _P , the representative velocity WS, the constant B, and the horizontal. The following equations (1) and (2) expressing the sold concentration C (x) at a distance x on the central axis using a plume range defined using the directional plume spreading width σ _y and the vertical directional plume spreading width σ _z . (Unit is all SI unit),

(In plume range)… (One)

(Outside the plumb range)… (2)
It is used as the said plume type, The search method of the abnormal oscillation source position of falling out. 9. The method of claim 8 wherein the horizontal plume spreading width σ _y, and the vertical direction of the plume spreading width σ _z wherein the longer and twice the side of the long axis, wherein the elliptically as speed twice the shorter side flume A plumbing cross-sectional shape perpendicular to the central axis, wherein the inside of the ellipse is within the plume range. The radiation dose of the falling-off sample collected at the evaluation point within the period T _d (i _t ) is measured, and the drop is based on the intensity of the measured radiation dose. It further has a sold out sorting process for classifying sold out for each sold out kind,
An abnormal oscillation source of falling dust, wherein the mass of falling dust of a portion corresponding to any one of the sold out kinds classified in the sold out species sorting step among the collected falling dust samples is the falling selling amount M. How to navigate the location.

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