JP7690652B2 - Search support system and search support method - Google Patents

Description

The present invention relates to a search support system and a search support method that can efficiently locate search subjects (hereinafter simply referred to as "subjects") such as lost children, elderly people, and animals.

Conventionally, there are known techniques for estimating the position of a target, such as a lost child or an animal. For example, Patent Document 1 discloses a position estimation device that acquires its own position (first position information), determines the distance between its own device and a transmitter based on a signal transmitted from the target's transmitter (first distance information), determines the position of another position estimation device (second position information) and the distance between the other position estimation device and the transmitter (second distance information), estimates the target's position based on the first position information, the first distance information, the second position information, and the second distance information, and outputs the estimated position.

JP 2018-124258 A

However, because the device in Patent Document 1 estimates the target's position from the relative positions of its own device and other position estimation devices, there are limitations to the accuracy of the estimation. This is because radio waves emitted from the transmitter may be diffracted by obstacles. As a result, even if a searcher goes to the estimated position, the target may not necessarily be present at this estimated position. In such cases, the searcher must thoroughly search all possible areas, which may take a long time to secure the target. In some cases, the target may be injured during the search.

The present invention has been made to solve the problems of the conventional technology described above, and aims to provide a search support system and a search support method that can efficiently secure a target person.

In order to solve the above problem, the present invention provides a search support system having a terminal device of a search requester requesting a search for a subject who is the subject of a search, a search information providing device that provides information related to the subject to the terminal device, a wireless tag carried by the subject, and a receiver that cooperates in the search for the subject , wherein when the receiver detects tag information of the wireless tag, it notifies the search information providing device of detection information including the detected tag information, the detection time of the tag information, position information of the device itself, and the distance and angle from the position of the device itself to the wireless tag, and the search information providing device stores within-display-range receiver management data including the position information of the receiver, a wireless tag signal receivable radius, and the ID of the wireless tag when the receiver detects the wireless tag, which are generated based on the detection information notified from the receiver, and the coordinate range of the area where the subject was located and the angle of the direction of movement from the coordinate range of the area where the subject was located, obtained based on the coordinates of the area where the subject was located at the specified time, the coordinates of the receiver at the specified time, and the coordinates of the receiver at the predetermined time going back a predetermined time interval from the specified time; a storage means for storing in the storage means display data storing the coordinate range of the area where the subject was located within a fixed time period in the past up to the specified time point and the angle of the direction of movement, obtained as an output of the first calculation means; and a notification means for notifying the terminal device of the contents of the display data, wherein the terminal device is equipped with a display means for displaying on a map the area where the subject was located within a fixed time period in the past up to the specified time point and the angle of the direction of movement in the form of an arrow having a width based on the radius of radio tag signal reception of the receiver, based on the contents of the display data .

In addition, in the above invention, the search information providing device further comprises: a presence tendency density function map in which presence tendency information representing the degree of the tendency of pedestrians to be present in an area is stored for each position coordinate with a preset value set as a probability value in the memory means; a storage means for storing time series information of the position coordinates, movement speed and movement direction of the wireless tag in the memory means; a generation means for performing statistical processing on the time series information stored in the memory means to generate a predicted position probability density function map; and a second calculation means for calculating a probability density function from the presence tendency density function map and the predicted position probability density function map, and the display means displays information regarding areas in which the subject is likely to be present from the specified time point onwards, based on the values of each area obtained as an output of the second calculation means, in a color-coded format on a map.
In the present invention, in the above-mentioned invention, the statistical processing includes determining an average value and a variance value and reflecting the average value and the variance value in the predicted position probability density function map.
In the present invention, in the above-mentioned invention, the statistical processing is performed by giving a high weight to data immediately before the time of prediction.
In addition, in the above invention, the present invention is characterized in that, in the statistical processing, the predicted movement speed is calculated as an average value for the entire section weighted by a short-term scalar value, and the predicted movement direction is calculated as an average value of the movement direction angle weighted by a short-term or long-term value.
In the above invention, the statistical processing includes calculating an average value of the predicted movement direction as an average value of a long-term vector, and calculating a variance value as a variance value of a short-term vector.

The present invention also provides a search support method in a search support system having a terminal device of a search requester requesting a search for a subject who is the subject of a search, a search information providing device providing information related to the subject to the terminal device, a wireless tag carried by the subject, and a receiver cooperating in the search for the subject, the method including a notification step of, when the receiver detects tag information of the wireless tag, notifying the search information providing device of detection information including the detected tag information, the detection time of the tag information, position information of the device itself, and the distance and angle from the position of the device itself to the wireless tag, a storage step of the search information providing device storing in a storage unit within-display-range receiver management data including the position information of the receiver, a wireless tag signal receivable radius , and an ID of the wireless tag when the receiver detects the wireless tag, the search information providing device storing in a storage unit within-display-range receiver management data including the wireless tag signal receivable radius of the receiver at a predetermined time point, the wireless tag signal receivable radius of the receiver, and the ID of the wireless tag when the receiver detects the wireless tag, the search information providing device storing in a storage unit within-display-range receiver management data including the wireless tag signal receivable radius of the receiver at a predetermined time point, the wireless tag signal receivable radius of the receiver at a predetermined time point, and the search information providing device stores in the memory unit display data obtained as an output of the first calculation step, the display data storing the coordinate range of the area where the subject was located within a certain time period in the past up to the specified time point and the angle of the direction of movement; a second notification step in which the search information providing device notifies the terminal device of the contents of the display data; and a display step in which the terminal device displays on a map, based on the contents of the display data, the area where the subject was located within a certain time period in the past up to the specified time point and the angle of the direction of movement in the form of an arrow having a width based on a radius of receivable a radio tag signal of the receiver .

The present invention allows for efficient securing of eligible individuals.

FIG. 1 is a diagram illustrating an overview of a search support system according to a first embodiment. FIG. 2 is a diagram showing a system configuration of the search support system according to the first embodiment. FIG. 3 is a diagram showing a configuration of the information aggregating server shown in FIG. FIG. 4 is a diagram showing an example of the wireless tag management data, the receiver management data, and the mobile receiver display setting data shown in FIG. FIG. 5 is a diagram showing an example of the detection information display setting data, the within-display-range receiver management data, and the display data shown in FIG. FIG. 6 is a diagram illustrating an example of image data according to the first embodiment. FIG. 7 is a flowchart (part 1) illustrating a processing procedure of the information aggregating server according to the first embodiment. FIG. 8 is a flowchart (part 2) illustrating the processing procedure of the information aggregating server according to the first embodiment. FIG. 9 is a flowchart (part 3) illustrating the processing procedure of the information aggregating server according to the first embodiment. FIG. 10 is a diagram illustrating an example of movement of a subject and placement of receivers according to the first embodiment. FIG. 11 is a diagram (part 1) showing an example of image data according to the first embodiment. FIG. 12 is a diagram (part 2) showing an example of image data according to the first embodiment. FIG. 13 is a diagram (part 3) showing an example of image data according to the first embodiment. FIG. 14 is a diagram illustrating an overview of a search support system according to the second embodiment. FIG. 15 is a diagram illustrating a configuration of an information aggregating server according to the second embodiment. FIG. 16 is a diagram showing an example of the receiver management data and the within-display-range receiver management data shown in FIG. FIG. 17 is a diagram showing an example of the display data shown in FIG. FIG. 18 is a diagram illustrating a method for identifying the moving direction of a subject according to the second embodiment. FIG. 19 is a diagram illustrating an example of image data according to the second embodiment. FIG. 20 is a flowchart (part 1) illustrating a processing procedure of the information aggregating server according to the second embodiment. FIG. 21 is a flowchart (part 2) illustrating the processing procedure of the information aggregating server according to the second embodiment. FIG. 22 is a flowchart (part 3) illustrating the processing procedure of the information aggregating server according to the second embodiment. FIG. 23 is a flowchart (part 4) illustrating the processing procedure of the information aggregating server according to the second embodiment. FIG. 24 is a diagram illustrating an example of display data during processing by the information aggregating server according to the second embodiment. FIG. 25 is a diagram (part 1) showing an example of image data according to the second embodiment. FIG. 26 is a diagram (part 2) showing an example of image data according to the second embodiment. FIG. 27 is a diagram (part 3) showing an example of image data according to the second embodiment. FIG. 28 is a diagram illustrating an overview of a search support system according to the third embodiment. FIG. 29 is a diagram for explaining a display method using a probability density function according to the third embodiment. FIG. 30 is a diagram illustrating an example of image data according to the third embodiment.

[Embodiment 1]
A search support system and a search support method according to the present embodiment 1 will be described in detail below. In the present embodiment 1, a searcher carrying a mobile receiver searches for a target person such as a lost child or an elderly person. The target person is assumed to carry a wireless tag that transmits radio waves for short-range wireless communication such as BLE (Bluetooth Low Energy; "Bluetooth" is a registered trademark).

<Outline of search support system according to embodiment 1>
First, an overview of the search support system according to the present embodiment 1 will be described. Fig. 1 is an explanatory diagram for explaining the overview of the search support system according to the present embodiment 1. Here, for convenience of explanation, a case will be shown in which an information aggregation server (HTTP server) generates image data in a bitmap format, and in response to an HTTP request by a web browser or an application on the mobile terminal of the searcher, the information aggregation server transmits the image data in the bitmap format to the mobile terminal of the searcher, and the image data is displayed on the operation display unit of the mobile terminal of the searcher.

The search support system includes a receiver carried by a collaborator (mobile body) who cooperates in the search for the target person, or a receiver installed on the collaborator's bicycle or automobile (hereinafter referred to as a "mobile receiver"), and a fixed receiver that is permanently installed in a predetermined location. In this embodiment, the mobile receiver and the fixed receiver are collectively referred to as the "receiver."

The receiver acquires the position coordinates of its own device measured by GPS (Global Positioning System) at preset intervals (e.g., 10 seconds) and notifies the acquired position coordinates together with the current time to an information aggregation server described below as receiver position data. In addition, when radio waves transmitted from a wireless tag carried by the subject are received, the receiver acquires the position coordinates of its own device measured by GPS, and notifies the acquired position coordinates and the wireless tag identification information (hereinafter referred to as "wireless tag ID") contained in the radio waves received from the wireless tag to the information aggregation server as detection information (detection data) together with the time the wireless tag ID was received.

The information aggregation server manages the receiver's position coordinates and time information included in the receiver position data received from the receiver in association with each other. The information aggregation server also manages the wireless tag ID, receiver's position coordinates, and time information included in the detection data received from the receiver in association with each other. When a search request for a target person is received from the searcher's mobile terminal, search information indicating the area in which the target person was present within a certain period of time (T2) in the past up to time t2 is generated based on the wireless tag ID, receiver's position coordinates, and time information, and the generated search information is transmitted to the mobile terminal. In other words, the information aggregation server makes it easy for the searcher to narrow down the search range by displaying an image of the area in which the target person was present within a certain period of time (T2) in the past up to time t2. In this embodiment 1, the period from a time a certain period of time back from a certain time t2 to time t2 is expressed as "a certain period of time in the past up to time t2".

For example, as an example of such search information, the image shown in FIG. 1 can be transmitted to a mobile terminal. This image includes a circular detectable area centered on the receiver's position coordinates according to the receiver's capabilities (for example, a receivable radius of several meters to several tens of meters). Here, if the receiver detects a wireless tag, the inside of the circle is colored 1 (for example, blue), and if it does not detect a wireless tag, the circle is colored 2 (for example, black). Also, the area where a wireless tag can be detected at each point to which the mobile receiver has moved within a certain period of time (T1) up to time t1 is colored 3 (for example, gray). Also, when the receiver detects a wireless tag within a certain period of time (T2) up to time t2, the circular boundary of the detectable area centered on the position coordinates of the detection point according to the receiver's capabilities is colored 4 (for example, navy blue).

As shown in FIG. 1, at time t1, the fixed receiver 1B detects the target person's wireless tag, while the other receivers do not detect the wireless tag (S1).

At time t2, the mobile receiver 1A detects the target person's wireless tag, while the other receivers do not. As a result, the color of the detectable area of the fixed receiver 1B changes from color 1 at time t1 to color 2 at time t2. In addition, because the fixed receiver 1B detected the target person's wireless tag within a certain period of time (T2) in the past up to time t2, the circular boundary of the detectable area of the fixed receiver 1B at time t2 changes to color 4 (S2).

At time t3, none of the receivers have detected the target person's wireless tag. As a result, the color of the detectable area of the mobile receiver 1A changes from color 1 at time t2 to color 2. Furthermore, because wireless tags were detected at the fixed receiver 1B and at two locations along the road within a certain period of time (T3) prior to time t3, the border color of the detectable circular area of the receiver at each time is displayed as color 4 (S3).

In this way, the search support system according to the first embodiment allows the searcher to narrow down the search area by providing the area in which the target person's wireless tag was present within a certain period of time in the past.

<System Configuration>
Next, the system configuration of the search support system according to the present embodiment 1 will be described. Fig. 2 is a diagram showing the system configuration of the search support system according to the present embodiment 1. The search support system shown in Fig. 2 is a system including a wireless tag 10, a fixed receiver 20, a mobile receiver 30, an information aggregation server 40, and a mobile terminal 50. The wireless tag 10 can communicate with the fixed receiver 20 and the mobile receiver 30 by BLE communication, and the fixed receiver 20, the mobile receiver 30, and the mobile terminal 50 can communicate with the information aggregation server 40 via the Internet. Note that a network other than the Internet can also be used.

The wireless tag 10 is a device carried by the subject and transmits its own wireless tag ID via BLE radio waves. Here, the wireless tag ID is transmitted every preset time (e.g., 10 seconds).

The fixed receiver 20 is installed in a building along a road, and is a device that receives BLE radio waves from the wireless tag 10. This fixed receiver 20 stores its own position coordinates measured by GPS and its own receiver ID, and transmits its own receiver ID, position coordinates, and current time to the information aggregation server 40 as receiver position data at preset intervals (e.g., 10 seconds). In addition, when a BLE radio wave is received, the wireless tag ID, receiver ID, its own position coordinates, and the reception time of the wireless tag ID carried on the BLE radio wave are transmitted to the information aggregation server 40 as detection data. Note that in this embodiment 1, multiple fixed receivers 20 may be referred to as fixed receivers 1B, 2B, and 3B.

The mobile receiver 30 is a mobile terminal such as a smartphone carried by a collaborator who cooperates in the search for the target person, and has a function of acquiring the position coordinates of the device by GPS and a function of receiving BLE radio waves. The receiver ID of the device is stored in the storage unit. A dedicated application is installed in the mobile receiver 30 in advance. The dedicated application transmits the receiver ID of the device, the position coordinates of the device acquired by GPS, and the current time to the information aggregation server 40 as receiver position data at preset intervals (e.g., 10 seconds). When the BLE radio waves are received, the wireless tag ID carried on the BLE radio waves, the receiver ID, the position coordinates of the device acquired by GPS, and the reception time of the wireless tag ID are transmitted to the information aggregation server 40 as detection data. In this embodiment 1, when multiple mobile receivers 30 are indicated, they may be written as mobile receivers 1A, 2A, and 3A.

The information aggregation server 40 is a server device that manages the location of the searcher, and transmits image data to the mobile terminal 50 in response to a "search request for the target person" from the mobile terminal 50 of the searcher. Specifically, when the information aggregation server 40 receives the receiver ID, location coordinates, and time information as receiver location data from the fixed receiver 20 and the mobile receiver 30, it stores this information in the storage unit. In addition, when the information aggregation server 40 receives the wireless tag ID, receiver ID, location coordinates, and reception time of the wireless tag ID as detection data from the fixed receiver 20 and the mobile receiver 30, it stores this information in the storage unit. Furthermore, when the information aggregation server 40 receives a search request from the mobile terminal 50, it generates an image showing the search information of the target person and transmits it to the mobile terminal 50. The search information includes the current detection situation, the movement area of the mobile receiver 30 within a certain period of time (T1) in the past up to time t1, and the situation detected by the fixed receiver 20 within a certain period of time (T2) in the past up to time t2.

The mobile terminal 50 is a terminal device such as a smartphone carried by a searcher (e.g., a family member of the target person) searching for the target person, and has a function of communicating with the information aggregation server 40 and a function of displaying images sent from the information aggregation server 40. Note that a search app can be installed in advance on this mobile terminal 50, but it is also possible to access the information aggregation server 40 (HTTP server) or the like using a web browser to make a search request and display images sent from the information aggregation server 40.

<Configuration of information aggregation server 40 according to the first embodiment>
Next, a configuration of the information aggregating server 40 shown in Fig. 2 will be described. Fig. 3 is a block diagram showing the configuration of the information aggregating server 40 shown in Fig. 2. As shown in Fig. 3, the information aggregating server 40 is connected to a display unit 41 and an input unit 42, and has a communication unit 43, a storage unit 44, and a control unit 45.

The display unit 41 is a display device such as a liquid crystal panel or a display device. The input unit 42 is an input device such as a keyboard or a mouse. The communication unit 43 is an interface unit for communicating with the fixed receiver 20, the mobile receiver 30, and the mobile terminal 50 via the Internet.

The memory unit 44 is a storage device such as a hard disk drive or non-volatile memory, and stores wireless tag management data 44a, receiver management data 44b, mobile receiver display setting data 44c, detection information display setting data 44d, display range receiver management data 44e, image data 44f, map data 44g, and display data 44h.

The wireless tag management data 44a is data that associates the subject ID, wireless tag ID, searcher ID, etc., related to the subject. The receiver management data 44b is data that associates the position coordinates of the receiver at each time, the wireless tag ID received by the receiver, etc.

The mobile receiver display setting data 44c is data indicating the display setting time of the mobile receiver 30. This is the display setting time for displaying on a map the detection area that the mobile receiver 30 covered for a certain period of time in the past. The detection information display setting data 44d is data indicating the display setting time of the detection information. The receiver management data within the display range 44e is data within the receiver management data 44b that is within the area requested to be searched by the mobile terminal 50.

Display data 44h is data consisting of the coordinates of the center point and radius of the receiver's detection range, etc., for drawing on a map the area of the presence of the subject for which a search request has been made from the mobile terminal 50. Map data 44g is color map data formed, for example, from RGB. Note that such map data 44g may also be an image in another format, such as a vector image. Image data 44f is image data that displays on a map the area of the presence of the subject for which a search request has been made from the mobile terminal 50. In this embodiment, display data 44h is generated once, and then image data 44f is generated from this display data 44h and map data 44g.

The control unit 45 is a control unit that performs overall control of the information aggregation server 40, and has a wireless tag management unit 45a, a receiver management unit 45b, a display setting unit 45c, an image data generation unit 45d, and an image data notification unit 45i. In practice, these programs are loaded into a CPU (Central Processing Unit) and executed, causing the wireless tag management unit 45a, the receiver management unit 45b, the display setting unit 45c, the image data generation unit 45d, and the image data notification unit 45i to execute processes corresponding to each of them.

The wireless tag management unit 45a is a processing unit that manages the wireless tag management data 44a. The wireless tag management unit 45a accepts the wireless tag ID, the target ID, the searcher ID, etc. from the input unit 42 and stores them in the wireless tag management data 44a.

The receiver management unit 45b is a processing unit that manages the receiver management data 44b. When the receiver management unit 45b receives receiver position data from the fixed receiver 20 and the mobile receiver 30, it stores the received wireless tag ID as "none" in the receiver management data 44b along with the time information, receiver ID, and position coordinates contained in the receiver position data. When the receiver management unit 45b receives detection data from the fixed receiver 20 and the mobile receiver 30, it stores the time of reception of the wireless tag ID contained in the detection data, the receiver ID, the position coordinates, and the received wireless tag ID in the receiver management data 44b.

The display setting unit 45c is a processing unit that manages the mobile receiver display setting data 44c and the detection information display setting data 44d. The display setting unit 45c accepts the mobile receiver display setting time and the detection information display setting time from the input unit 42, and stores them in the mobile receiver display setting data 44c and the detection information display setting data 44d. The image data notification unit 45i is a processing unit that notifies the mobile terminal 50 of the image data 44f.

The image data generating unit 45d is a processing unit that generates image data 44f, and has a display range data extracting unit 45e, a current information processing unit 45f, a mobile receiver past information processing unit 45g, a past detection information processing unit 45h, and a display data drawing unit 45j. The display range data extracting unit 45e is a processing unit that extracts data within the display range from the receiver management data 44b. The display range data extracting unit 45e extracts data that falls within the display range included in the search request from the mobile terminal 50 from the receiver management data 44b, and stores it in the display range receiver management data 44e.

The current information processing unit 45f is a processing unit that generates display data 44h including the current detection situation. The current information processing unit 45f extracts data from the within-display-range receiver management data 44e at the time immediately prior to the specified time t included in the search request. The current information processing unit 45f includes the position coordinates of the extracted data as the drawing coordinates, the reception radius as the drawing radius, and the received wireless tag ID as the wireless tag ID in the display data 44h together with the time of the extracted data and the receiver ID.

The current information processing unit 45f identifies the wireless tag ID of the target from the wireless tag management data 44a using the target ID or searcher ID included in the search request. If the wireless tag ID of the target is included in the received wireless tag ID of the extracted data, the current information processing unit 45f sets the area drawing color of the data to color 1, and if the wireless tag ID of the target is not included, sets the area drawing color of the data to color 2 and includes it in the display data 44h.

The mobile receiver past information processing unit 45g is a processing unit that processes the movement area of the mobile receiver 30 within a certain period of time (T1) in the past up to time t1 and includes it in the display data 44h. The mobile receiver past information processing unit 45g extracts data from the within-display-range receiver management data 44e that is earlier than the time immediately preceding the specified time t included in the search request and is obtained by subtracting the mobile receiver display setting time in the mobile receiver display setting data 44c from the specified time t.

The mobile receiver past information processing unit 45g searches for data extracted from the receiver management data within the display range 44e, and if it corresponds to the mobile receiver 30, it includes the area drawing color of the searched data as color 3, the position coordinates as drawing coordinates, the reception radius as drawing radius, together with the time of the searched data and the receiver ID in the display data 44h.

The past detection information processing unit 45h is a processing unit that processes the situation detected by the receiver within a certain period of time (T2) in the past up to time t2 and includes it in the display data 44h. The past detection information processing unit 45h extracts data from the within-display-range receiver management data 44e that is earlier than the time immediately preceding the specified time t included in the search request and is obtained by subtracting the detection information display setting time in the detection information display setting data 44d from the specified time t.

The past detection information processing unit 45h searches for data extracted from the receiver management data 44e within the display range, and if the received wireless tag ID includes the wireless tag ID of the target person, sets the border color to color 4, and includes the position coordinates of the searched data as the drawing coordinates and the reception radius as the drawing radius in the display data 44h together with the time and receiver ID of the searched data.

The display data drawing unit 45j is a processing unit that generates image data 44f from the display data 44h and the map data 44g. The display data drawing unit 45j generates image data 44f by drawing a circle with a center point at the drawing coordinates included in the display data 44h and a radius equal to the drawing radius, with the interior in a color corresponding to the area drawing color and the boundary in a color corresponding to the boundary color, overlaid on the map data 44g.

Next, an example of data stored in the memory unit 44 shown in Figure 3 will be described. Figures 4 and 5 are diagrams showing examples of the wireless tag management data 44a, receiver management data 44b, mobile receiver display setting data 44c, detection information display setting data 44d, within-display range receiver management data 44e, and display data 44h shown in Figure 3.

The wireless tag management data 44a shown in FIG. 4(a) shows the situation in which the subject ID "A101", subject name "Takken Taro", subject contact information "090-1234-5678", subject address "Shinjuku-ku, Tokyo...", searcher ID "B101", searcher name "Takken Hanako" and searcher contact information "080-2345-6789" are associated with the wireless tag ID "R001".

The receiver management data 44b shown in FIG. 4(b) shows a situation in which fixed/mobile "fixed", position coordinates "x1/y1", receiving radius "20m" and receiving wireless tag ID "none" are associated with receiver ID "101" at time "t1", fixed/mobile "fixed", position coordinates "x2/y2", receiving radius "20m" and receiving wireless tag ID "none" are associated with receiver ID "102" at time "t1", fixed/mobile "fixed", position coordinates "x3/y3", receiving radius "20m" and receiving wireless tag ID "R001" are associated with receiver ID "103" at time "t1", and fixed/mobile "mobile", position coordinates "x11/y11", receiving radius "5m" and receiving wireless tag ID "none" are associated with receiver ID "201" at time "t1".

The figure also shows a situation in which fixed/mobile "mobile", position coordinates "x21/y21", reception radius "5m" and reception wireless tag ID "none" are associated with receiver ID "202" at time "t1", fixed/mobile "mobile", position coordinates "x31/y31", reception radius "5m" and reception wireless tag ID "none" are associated with receiver ID "203" at time "t1", fixed/mobile "fixed", position coordinates "x1/y1", reception radius "20m" and reception wireless tag ID "none" are associated with receiver ID "101" at time "t2", and fixed/mobile "fixed", position coordinates "x2/y2", reception radius "20m" and reception wireless tag ID "none" are associated with receiver ID "102" at time "t2".

The figure also shows a situation in which fixed/mobile "fixed", position coordinates "x3/y3", reception radius "20m" and reception wireless tag ID "none" are associated with receiver ID "103" at time "t2", fixed/mobile "moving", position coordinates "x12/y12", reception radius "5m" and reception wireless tag ID "none" are associated with receiver ID "201" at time "t2", fixed/mobile "moving", position coordinates "x22/y22", reception radius "5m" and reception wireless tag ID "R001" are associated with receiver ID "203" at time "t2", fixed/mobile "moving", position coordinates "x32/y32", reception radius "5m" and reception wireless tag ID "none" are associated with receiver ID "203" at time "t2".

The mobile receiver display setting data 44c shown in FIG. 4(c) shows a situation where the mobile receiver display setting time is set to "1 minute." The detection information display setting data 44d shown in FIG. 5(a) shows a situation where the detection information display setting time is set to "5 minutes."

The display range receiver management data 44e shown in FIG. 5(b) shows a situation in which fixed/mobile "fixed", position coordinates "x1/y1", receiving radius "20m" and receiving wireless tag ID "none" are associated with receiver ID "101" at time "t1", fixed/mobile "fixed", position coordinates "x3/y3", receiving radius "20m" and receiving wireless tag ID "R001" are associated with receiver ID "103" at time "t1", fixed/mobile "moving", position coordinates "x11/y11", receiving radius "5m" and receiving wireless tag ID "none" are associated with receiver ID "201" at time "t1", and fixed/mobile "moving", position coordinates "x21/y21", receiving radius "5m" and receiving wireless tag ID "none" are associated with receiver ID "202" at time "t1".

The figure also shows a situation in which fixed/mobile "fixed", position coordinates "x1/y1", reception radius "20m" and receiving wireless tag ID "none" are associated with receiver ID "101" at time "t2", fixed/mobile "fixed", position coordinates "x3/y3", reception radius "20m" and receiving wireless tag ID "none" are associated with receiver ID "103" at time "t2", fixed/mobile "moving", position coordinates "x22/y22", reception radius "5m" and receiving wireless tag ID "R001" are associated with receiver ID "203" at time "t2", fixed/mobile "moving", position coordinates "x32/y32", reception radius "5m" and receiving wireless tag ID "none" are associated with receiver ID "203" at time "t2".

Next, an example of display data 44h will be described. Figure 5 (c) is a diagram showing an example of display data 44h. As shown in FIG. 5(c), the display data 44h includes data of the receiver ID "101", wireless tag ID "R001", drawing coordinates "x1/y1", drawing radius "20m", area drawing color "color 1", and boundary color "-" at time "t8", data of the receiver ID "102", wireless tag ID "none", drawing coordinates "x2/y2", drawing radius "20m", area drawing color "color 2", and boundary color "-" at time "t8", data of the receiver ID "103", wireless tag ID "R005", drawing coordinates "x3/y3", drawing radius "20m", area drawing color "color 2", and boundary color "-" at time "t8", and data of the receiver ID "201", wireless tag ID "none", drawing coordinates "x18/y18", drawing radius "5m", area drawing color "color 2", and boundary color "-" at time "t8".

It also includes data for the receiver ID "202", wireless tag ID "none", drawing coordinates "x28/y28", drawing radius "5m", area drawing color "color 2", and border color "-" at time "t8", data for the receiver ID "203", wireless tag ID "R001", drawing coordinates "x38/y38", drawing radius "5m", area drawing color "color 2", and border color "color 4" at time "t8", data for the receiver ID "201", wireless tag ID "none", drawing coordinates "x17/y17", drawing radius "5m", area drawing color "color 3", and border color "-" at time "t7", and data for the receiver ID "202", wireless tag ID "none", drawing coordinates "x27/y27", drawing radius "5m", area drawing color "color 3", and border color "-" at time "t7".

In addition, the data includes the receiver ID "203", wireless tag ID "none", drawing coordinates "x37/y37", drawing radius "5m", area drawing color "color 3", and border color "-" at time "t7", the data includes the receiver ID "102", wireless tag ID "R001", drawing coordinates "x2/y2", drawing radius "20m", area drawing color "-", and border color "color 4" at time "t3", the data includes the wireless tag ID "R001", drawing coordinates "x22/y22", drawing radius "5m", area drawing color "-", and border color "color 4" for the receiver ID "202" at time "t2", and the data includes the wireless tag ID "R001", drawing coordinates "x3/y3", drawing radius "20m", area drawing color "-", and border color "color 4" for the receiver ID "103" at time "t1".

Display of Image Data According to First Embodiment
Next, an example of image data 44f according to the first embodiment will be described. Fig. 6 is a diagram showing an example of image data 44f according to the first embodiment. First, the display data drawing unit 45j develops map data 44g on a bitmap memory, generates a circle on the bitmap memory with a center point set to the drawing coordinates included in the display data 44h and a radius set to the drawing radius so as to be overlaid thereon, and draws the area and boundary of the circle in colors corresponding to the area drawing color and boundary color included in the display data 44h, respectively.

Specifically, the fixed receiver 1B shown in FIG. 6 has data immediately prior to time t as a circle with center point "(x1, y1)" and radius "r1" and color "color 2" (e.g., black). The mobile receiver 1A has data immediately prior to time t as a circle with center point "(x18, y18)" and radius "r2" and color "color 1" (e.g., blue).

In addition, detection data that is earlier than the time t and is between time t and the time obtained by subtracting the detection information display setting time of the detection information display setting data 44d is set to the boundary part of a circle with center point "(x1, y1)" and radius "r1" and is set to color "color 4" (for example, navy blue).

In addition, multiple circles are displayed in succession as mobile receiver data that is older than the closest time t and is between time t and the time obtained by subtracting the mobile receiver display setting time in the mobile receiver display setting data 44c. For example, one of the continuously displayed mobile receivers 1A is a circle with a center point "(x12, y12)" and a radius of "r2", and is colored "color 3" (for example, gray). Note that when multiple circles are displayed overlapping each other, they are displayed overlapping with the circle with the newer time in front.

<Processing procedure of the information aggregating server 40 according to the first embodiment>
Next, the processing procedure of the information aggregating server 40 will be described. Figures 7 to 9 are flowcharts showing the processing procedure of the information aggregating server 40. As shown in the figures, when the information aggregating server 40 receives receiver position data or detection data from the fixed receiver 20 or the mobile receiver 30 (step S101; Yes), the information aggregating server 40 stores the received data in the receiver management data 44b (step S102).

If neither receiver position data nor detection data has been received from the fixed receiver 20 or mobile receiver 30 (step S101; No), or if a search request has not been received from the mobile terminal 50 (step S103; No), proceed to step S101. On the other hand, if a search request has been received from the mobile terminal 50 (step S103; Yes), data within the display range is extracted from the receiver management data 44b based on the display range included in the search request, and stored in the within-display-range receiver management data 44e (step S104).

Then, data at the time immediately prior to the specified time t included in the search request is extracted from the within-display-range receiver management data 44e (step S105), and the position coordinates of the extracted data are included in the display data 44h as drawing coordinates and the reception radius is included in the drawing radius (step S106).

The wireless tag ID of the target person is identified from the wireless tag management data 44a using the target person ID or searcher ID included in the search request (step S107), and the top-level data is extracted from the display data 44h (step S108).

If the wireless tag ID of the extracted data includes the wireless tag ID of the subject (step S109; Yes), the area drawing color is included in the display data 44h as color 1 (step S110); if the wireless tag ID of the subject is not included (step S109; No), the area drawing color is included in the display data 44h as color 2 (step S111).

Then, the next data is extracted from the display data 44h (step S112), and if there is next data (step S113; No), the process proceeds to step S109. If there is no next data (step S113; Yes), the topmost data is extracted from the display data 44h (step S114).

Data with the same time and receiver ID as the extracted data is identified within the display range receiver management data 44e, and the data one level above it is extracted (step S115).

If the receiver of the extracted data is a mobile receiver 30 (step S116; Yes), the area drawing color is set to color 3, and the position coordinates of the data are included as drawing coordinates and the reception radius is included as drawing radius in the display data 44h (step S117). If the receiver of the data is a fixed receiver 20 (step S116; No), proceed to step S118.

The data one level above the data is extracted from the display range receiver management data 44e (step S118), and if the time of the extracted data is after the time t minus the mobile receiver display setting time of the mobile receiver display setting data 44c (step S119; No), proceed to step S116.

If the time of the data is earlier than the time t minus the mobile receiver display setting time (step S119; Yes), the topmost data is extracted from the display data 44h (step S120).

Data with the same time and receiver ID as the extracted data is identified from within the display range receiver management data 44e, and the data one level above it is extracted (step S121).

If the wireless tag ID of the extracted data includes the wireless tag ID of the subject (step S122; Yes), the border color is set to color 4, and the position coordinates of the data are included in the display data 44h as the drawing coordinates and the reception radius is included as the drawing radius (step S123). If the wireless tag ID of the data does not include the wireless tag ID of the subject (step S122; No), proceed to step S124.

The data one level above the data is extracted from the display range receiver management data 44e (step S124), and if the time of the extracted data is after the time t minus the detection information display setting time of the detection information display setting data 44d (step S125; No), proceed to step S122.

If the time of the data is earlier than the time t minus the detection information display setting time (step S125; Yes), image data 44f is generated from the display data 44h and the map data 44g and transmitted to the mobile device 50 (step S126), and the process ends.

<Display example of image data 44f according to the first embodiment>
Next, a description will be given of a specific example of display of the image data 44f according to the present embodiment 1. Fig. 10 is a diagram showing an example of movement of a subject and placement of a receiver, which are the premise of a specific example of display of the image data 44f according to the present embodiment 1.

As shown in Figure 10, a subject (represented by a double white circle) carrying a wireless tag 10 moves along the route shown by the dashed line from time t1 to t9. The fixed receivers 20 have a receiving radius of several tens of meters, and are installed at the black circles on the map as fixed receiver 1B, fixed receiver 2B, and fixed receiver 3B. When the subject passes within the outer circle of the black circle, which represents the receiving radius of several tens of meters of the fixed receiver 20, the fixed receiver 20 detects the wireless tag 10.

Mobile receiver 30 has a receiving radius of 10 m or less, and mobile receiver 1A, mobile receiver 2A, and mobile receiver 3A (shown as black circles) each move independently. At time t4, the subject passes within the outer circle of the black circle representing the range of mobile receiver 1A's receiving radius of 10 m or less, so mobile receiver 1A detects wireless tag 10, and similarly, mobile receiver 2A detects wireless tag 10 at time t2, and mobile receiver 3A detects wireless tag 10 at time t3.

Next, an example of the display of image data 44f according to this embodiment 1 will be described. Figures 11 to 13 are diagrams showing an example of the display of image data 44f according to this embodiment 1. Figure 11 is an example of the display at time t1. The area drawing color of the fixed receiver 3B is color 1, indicating that a wireless tag 10 has been detected. The area drawing colors of the other receivers are color 2 or color 3, indicating a situation in which a wireless tag 10 has not been detected.

Figure 12 is an example display at time t2. The area drawing color of the detectable circular area of the mobile receiver 2A is color 1, indicating that a wireless tag 10 has been detected. The area drawing color of the other receivers is color 2 or color 3, indicating a situation in which the wireless tag 10 is not detected at time t2 or between the time obtained by subtracting the mobile receiver display setting time from time t2 and time t2. Note that the border color of the detectable circular area of the fixed receiver 3B is color 4, indicating a situation in which the wireless tag 10 is detected between the time obtained by subtracting the detection information display setting time from time t2 and time t2.

Figure 13 is an example display at time t9. The area drawing color of the detectable circular area for all receivers is color 2 or color 3, and shows a situation in which no wireless tag 10 is detected at time t9 or from the time obtained by subtracting the mobile receiver display setting time from time t9 to time t9. Note that for fixed receiver 1B, fixed receiver 2B, and fixed receiver 3B, as well as the four locations near intersections a, b, and c, the border color of the detectable circular area for the receiver at each time is color 4, showing a situation in which a wireless tag 10 is detected from the time obtained by subtracting the detection information display setting time from time t9 to time t9.

In this way, the search support system according to the first embodiment allows the searcher to narrow down the search area by providing the area in which the target person was present within a certain period of time (T2) up to time t2.

[Embodiment 2]
Incidentally, in the above embodiment 1, a case has been described in which the receiver can detect only the presence or absence of radio waves received from the wireless tag 10; however, the present invention is not limited to this, and when the receiver is capable of detecting the distance and direction to the wireless tag 10 based on the received radio waves, it can also be configured to provide the area and direction of movement in which the subject was present within a certain period of time (T2) in the past up to time t2.

In this second embodiment, we will explain a case where the receiver is able to detect the distance and direction to the wireless tag 10 using radio waves received, and the area and direction of movement of the subject within a certain period of time (T2) in the past up to time t2 are provided.

<Outline of search support system according to embodiment 2>
First, an overview of the search support system according to the second embodiment will be described. FIG. 14 is an explanatory diagram for explaining an overview of the search support system according to the second embodiment. First, the receiver notifies the information aggregation server 100 (described later) of its own device's position coordinates together with the current time as receiver position data at preset intervals. In addition, when the receiver receives radio waves transmitted from the wireless tag 10 carried by the subject, it notifies the information aggregation server 100 (described later) of its own device's position coordinates, wireless tag ID, reception distance, and reception angle as detection information (detection data).

The information aggregation server 100 associates the receiver's position coordinates and time information contained in the receiver position data received from the receiver, and manages them as receiver management data 111, which will be described later. The information aggregation server 100 also associates the receiver's position coordinates, wireless tag ID, reception distance, reception angle, and time information contained in the detection data received from the receiver, and manages them as receiver management data 111, which will be described later. When a search request for a target person is accepted from the searcher's mobile terminal 50, search information indicating the area and movement direction of the target person within a certain period of time (T2) in the past up to time t2 is generated based on the receiver management data 111, and the generated search information is transmitted to the mobile terminal 50.

For example, as an example of such search information, the image shown in FIG. 14 can be transmitted to the mobile terminal 50. In this image, when the receiver detects the wireless tag 10 at time t, within the area detectable by the receiver detecting the wireless tag 10, an area with a low probability of the subject existing is shown as a circle in color 5 (e.g. light blue), an area with a high probability of the subject existing is shown as a rounded rectangle in color 1 (e.g. blue), an area with a high probability of the subject existing detected between the time obtained by subtracting the detection information display setting time from time t and time t is shown as a rounded rectangle in color 4 (e.g. navy blue), and the direction of movement of the subject is shown as an arrow in color 6 (e.g. yellow).

In addition, when the receiver does not detect the wireless tag 10, it is colored 2 (e.g., black), and the detectable area at each point to which the mobile receiver 30 moves between time t minus the mobile receiver display setting time and time t is colored 3 (e.g., gray).

As shown in FIG. 14, at time t1, the fixed receiver 1B detects the target person's wireless tag 10, and there is a high probability that the target person is moving in a 180 degree direction within the area indicated by the rounded rectangle of color 1 (S11).

At time t2, there is a high probability that the mobile receiver 1A detected the target person's wireless tag 10 and moved in the 270 degree direction through the area shown by the rounded rectangle in color 1, and there is a high probability that the mobile receiver 1A moved in the 180 degree direction through the area shown by the rounded rectangle in color 4 near the fixed receiver 1B between the time obtained by subtracting the detection information display setting time from time t2 and time t2 (S12).

At time t3, the target's wireless tag 10 has not been detected, but there is a high probability that the target moved in each direction in the area indicated by the rounded rectangle in color 4 near the fixed receiver 1B and along the road between the time obtained by subtracting the detection information display setting time from time t3 and time t3 (S13).

In this way, the search support system according to the second embodiment allows the searcher to narrow down the search area by providing the area and direction in which the target person was present within a certain period of time (T2) in the past up to time t2 when the distance and direction to the wireless tag 10 can be detected by the radio waves received by the receiver.

<Configuration of information aggregation server 100 according to the second embodiment>
Next, a configuration of the information aggregating server 100 according to the second embodiment will be described. Fig. 15 is a block diagram showing the configuration of the information aggregating server 100 according to the second embodiment. Note that a description of the same functional units as those of the information aggregating server 40 shown in Fig. 3 will be omitted.

As shown in FIG. 15, the information aggregation server 100 is connected to a display unit 41 and an input unit 42, and has a communication unit 43, a memory unit 110, and a control unit 120.

The storage unit 110 is a storage device such as a hard disk drive or non-volatile memory, and stores wireless tag management data 44a, receiver management data 111, mobile receiver display setting data 44c, detection information display setting data 44d, receiver management data within display range 112, image data 113, map data 44g, display data 114, and flag data for generating display data 115.

The receiver management data 111 is data that associates the position coordinates of the receiver at each time, the wireless tag ID received by the receiver, the reception distance, the reception angle, etc. The receiver management data within the display range 112 is data within the receiver management data 111 for the area requested for search by the mobile terminal 50. The display data 114 is data consisting of the drawing coordinates of the center point of the detection range of the receiver, the drawing radius, the drawing shape, etc., for drawing on a map the presence area of the subject requested for search by the mobile terminal 50. The image data 113 is image data that displays on a map the presence area of the subject requested for search by the mobile terminal 50. In this embodiment 2, the display data 114 is generated once, and then the image data 113 is generated from this display data 114 and the map data 44g. The display data generation flag data 115 is data that indicates whether generation of display data indicating the moving direction has started and indicates the receiver ID that is being updated in the display data.

The control unit 120 is a control unit that performs overall control of the information aggregation server 100, and has a wireless tag management unit 45a, a receiver management unit 121, a display setting unit 45c, an image data generation unit 122, and an image data notification unit 45i. In practice, these programs are loaded into the CPU and executed, causing the wireless tag management unit 45a, the receiver management unit 121, the display setting unit 45c, the image data generation unit 122, and the image data notification unit 45i to execute processes corresponding to each of them.

The receiver management unit 121 is a processing unit that manages the receiver management data 111. When the receiver management unit 121 receives receiver position data from the fixed receiver 20 and the mobile receiver 30, it stores the received wireless tag ID as "none" in the receiver management data 111 along with the time information, receiver ID, and position coordinates contained in the receiver position data.

When the receiver management unit 121 receives detection data from the fixed receiver 20 and the mobile receiver 30, it stores the time when the wireless tag ID included in the detection data was received, the receiver ID, the position coordinates, the received wireless tag ID, the reception distance, the reception angle, etc. in the receiver management data 111.

The image data generation unit 122 is a processing unit that generates image data 113, and has a display range data extraction unit 123, a current information processing unit 124, a mobile receiver past information processing unit 45g, a detailed detection information processing unit 125, a coordinate calculation unit 126, a display data change processing unit 127, a movement direction calculation unit 128, and a display data drawing unit 129.

The within-display-range data extraction unit 123 is a processing unit that extracts data within the display range from the receiver management data 111. The within-display-range data extraction unit 123 extracts data that falls within the display range included in the search request from the mobile terminal 50 from the receiver management data 111, and stores the data in the within-display-range receiver management data 112.

The current information processing unit 124 is a processing unit that generates display data 114 including the current detection situation. The current information processing unit 124 extracts data from the within-display-range receiver management data 112 at the time immediately prior to the specified time t included in the search request. The current information processing unit 124 sets the shape to a circle, and includes the position coordinates of the extracted data as drawing coordinates 1 and the reception radius as a drawing radius in the display data 114.

The current information processing unit 124 identifies the wireless tag ID of the target from the wireless tag management data 44a using the target ID or searcher ID included in the search request. The current information processing unit 124 searches the display data 114, and if the received wireless tag ID includes the target's wireless tag ID, it sets the area drawing color of that data to color 5, and if the received wireless tag ID is "none", it includes the area drawing color of that data in the display data 114 as color 2.

The detailed detection information processing unit 125 is a processing unit that processes the situation detected by the fixed receiver 20 and the mobile receiver 30 within a certain period of time (T2) in the past up until time t2, and includes it in the display data 114. The detailed detection information processing unit 125 extracts data from the within-display-range receiver management data 112 that is earlier than the time immediately preceding the specified time t included in the search request and that is obtained by subtracting the detection information display setting time of the detection information display setting data 44d from the specified time t, and stores "not generated" in the movement direction data of the display data generation flag data 115.

The detailed detection information processing unit 125 searches for data extracted from the display range receiver management data 112, and if the received wireless tag ID includes the wireless tag ID of the target person and the lowest data in the display data 114 is different from the receiver ID of the extracted data, or if processing is handed over from the display data change processing unit 127, stores the receiver ID of the extracted data and "generated" in the display data generation flag data 115. The detailed detection information processing unit 125 sets the drawing shape to a circle, and includes the position coordinates of the received wireless tag 10 calculated by the coordinate calculation unit 126 as drawing coordinate 1 and 1/5 of the reception radius as a drawing radius in the display data 114. If the time of the extracted data is the same as t, the detailed detection information processing unit 125 sets the area drawing color to color 1 and includes it in the display data 114 as color 4 if it is different from t.

The detailed detection information processing unit 125 searches for the extracted data from the display range receiver management data 112, and if the received wireless tag ID includes the wireless tag ID of the target person and the receiver ID of the lowest data in the display data 114 is the same as the extracted data, it passes the processing to the display data change processing unit 127.

The coordinate calculation unit 126 is a processing unit that calculates the position coordinates of the wireless tag 10. The coordinate calculation unit 126 calculates the position coordinates of the wireless tag 10 from the reception distance and reception angle associated with the received wireless tag ID in the display range receiver management data 112.

If the movement direction data in the flag data 115 for generating display data is "not generated" or the receiver ID of the extracted data is different from the receiver ID being updated in the display data in the flag data 115 for generating display data, the display data change processing unit 127 passes the process to the detailed detection information processing unit 125.

If the movement direction data in the flag data 115 for generating display data is "already generated" and the receiver ID of the extracted data is the same as the receiver ID being updated in the display data in the flag data 115 for generating display data, the display data change processing unit 127 checks the shape of the lowest data in the display data 114.

If the shape of the lowest-level data in the display data 114 is a circle, the display data change processing unit 127 changes the drawing shape of that data to a rounded rectangle, resets the position coordinates calculated by the coordinate calculation unit 126 for the received wireless tag 10 as coordinate 2, and includes it in the display data 114. Using the midpoint coordinate and angle calculated by the movement direction calculation unit 128 using that data, the display data change processing unit 127 sets the midpoint coordinate as drawing coordinate 1, the drawing shape as an arrow and angle, and the area drawing color as color 6, which are included in the display data 114.

If the shape of the lowest data in the display data 114 is not a circle, the display data change processing unit 127 extracts the data one level above that data, resets the position coordinates calculated by the coordinate calculation unit 126 for the received wireless tag 10 as drawing coordinates 2 of that data, and includes it in the display data 114. Using the midpoint coordinate and angle calculated by the movement direction calculation unit 128 using the extracted data, the display data change processing unit 127 resets the midpoint coordinate of the lowest data in the display data 114 to drawing coordinates 1 and the drawing shape to an arrow with angle, and includes it in the display data 114.

The movement direction calculation unit 128 is a processing unit that calculates the position coordinates of the midpoint between two points and the angle from drawing coordinate 1 to drawing coordinate 2 based on the given drawing coordinate 1 and drawing coordinate 2.

Next, a specific example of data stored in the storage unit 110 of the information aggregation server 100 shown in FIG. 15 will be described. FIGS. 16 and 17 are diagrams showing examples of the receiver management data 111, within-display-range receiver management data 112, display data 114, and flag data for generating display data 115 shown in FIG. 15.

The receiver management data 111 shown in FIG. 16(a) associates fixed/moving "fixed", position coordinates "x1/y1", receiving radius "20 m", receiving wireless tag ID "R001", receiving distance "20 m" and receiving angle "300 degrees" with the receiver ID "101" at time "t1", and associates fixed/moving "fixed", position coordinates "x2/y2", receiving radius "20 m", receiving wireless tag ID "none", receiving distance "-" and receiving angle "300 degrees" with the receiver ID "102" at time "t1". The figure shows a situation in which fixed/moving "fixed", position coordinates "x3/y3", reception radius "20m", receiving wireless tag ID "none", reception distance "-" and reception angle "-" are associated with receiver ID "103" at time "t1", and fixed/moving "moving", position coordinates "x11/y11", reception radius "5m", receiving wireless tag ID "none", reception distance "-" and reception angle "-" are associated with receiver ID "201" at time "t1".

The figure also shows a situation in which fixed/moving "fixed", position coordinates "x1/y1", receiving radius "20m", receiving wireless tag ID "R001", receiving distance "15m" and receiving angle "240 degrees" are associated with receiver ID "101" at time "t1.4", fixed/moving "fixed", position coordinates "x1/y1", receiving radius "20m", receiving wireless tag ID "R001", receiving distance "20m" and receiving angle "210 degrees" are associated with receiver ID "101" at time "t1.5", and fixed/moving "fixed", position coordinates "x1/y1", receiving radius "20m", receiving wireless tag ID "none", receiving distance "-" and receiving angle "-" are associated with receiver ID "101" at time "t1.6".

In addition, fixed/mobile "moving", position coordinates "x21i/y21i", receiving radius "5m", receiving wireless tag ID "R001", receiving distance "5m" and receiving angle "330 degrees" are associated with receiver ID "202" at time "t1.8", and fixed/mobile "moving", position coordinates "x21j/y21j", receiving radius "5m", receiving wireless tag ID "R001", receiving distance "5m" and receiving angle "0 degrees" are associated with receiver ID "202" at time "t1.9". , the receiver ID "202" at time "t2" is associated with fixed/mobile "mobile", position coordinates "x22a/y22a", reception radius "5m", receiving wireless tag ID "R001", reception distance "5m" and reception angle "30 degrees", and the receiver ID "202" at time "t2.1" is associated with fixed/mobile "mobile", position coordinates "x22b/y22b", reception radius "5m", receiving wireless tag ID "none", reception distance "-" and reception angle "-".

The receiver management data 112 within the display range shown in FIG. 16(b) associates fixed/moving "fixed", position coordinates "x1/y1", receiving radius "20 m", receiving wireless tag ID "R001", receiving distance "20 m" and receiving angle "300 degrees" with the receiver ID "101" at time "t1", and associates fixed/moving "fixed", position coordinates "x3/y3", receiving radius "20 m", receiving wireless tag ID "none", receiving distance "-" and receiving angle "-" with the receiver ID "103" at time "t1". The figure shows a situation where the receiver ID "101" at time "t1.4" is associated with fixed/moving "fixed", position coordinates "x1/y1", receiving radius "20m", receiving wireless tag ID "R001", receiving distance "15m" and receiving angle "240 degrees", and the receiver ID "101" at time "t1.5" is associated with fixed/moving "fixed", position coordinates "x1/y1", receiving radius "20m", receiving wireless tag ID "R001", receiving distance "20m" and receiving angle "210 degrees".

In addition, the receiver ID "101" at time "t1.6" is associated with fixed/mobile "fixed", position coordinates "x1/y1", reception radius "20 m", reception wireless tag ID "none", reception distance "-" and reception angle "-", and the receiver ID "202" at time "t1.8" is associated with fixed/mobile "mobile", position coordinates "x21i/y21i", reception radius "5 m", reception wireless tag ID "R001", reception distance "5 m" and reception angle "330 degrees". This shows a situation in which the receiver ID "202" at time "t2" is associated with fixed/mobile "mobile", position coordinates "x21j/y21j", reception radius "5m", receiving wireless tag ID "R001", reception distance "5m" and reception angle "0 degrees", and the receiver ID "202" at time "t2" is associated with fixed/mobile "mobile", position coordinates "x22a/y22a", reception radius "5m", receiving wireless tag ID "R001", reception distance "5m" and reception angle "30 degrees".

The display data 114 shown in FIG. 17(a) includes data of the receiver ID "101", wireless tag ID "none", drawing coordinate 1 "x1/y1", drawing coordinate 2 "-", drawing radius "20m", area drawing color "color 2" and drawing shape "circle" at time "t8", data of the receiver ID "102", wireless tag ID "none", drawing coordinate 1 "x2/y2", drawing coordinate 2 "-", drawing radius "20m", area drawing color "color 2" and drawing shape "circle" at time "t8", data of the receiver ID "103", wireless tag ID "none", drawing coordinate 1 "x3/y2", drawing coordinate 2 "-", drawing radius "20m", area drawing color "color 2" and drawing shape "circle" at time "t8", It includes data for time "t8" of "201", wireless tag ID "none", drawing coordinate 1 "x18a/y18a", drawing coordinate 2 "-", drawing radius "5m", area drawing color "color 2", and drawing shape "circle", as well as data for time "t8" of "202", wireless tag ID "none", drawing coordinate 1 "x28a/y28a", drawing coordinate 2 "-", drawing radius "5m", area drawing color "color 2", and drawing shape "circle".

In addition, data for the receiver ID "203", wireless tag ID "R001", drawing coordinate 1 "x38a/y38a", drawing coordinate 2 "-", drawing radius "5m", area drawing color "color 5", and drawing shape "circle" at time "t8", and data for the receiver ID "201", wireless tag ID "none", drawing coordinate 1 "x17j/y17j", drawing coordinate 2 "-", drawing radius "5m", area drawing color "color 3", and drawing shape "circle" at time "t7.9", It includes data for time "t7.9" of receiver ID "202", wireless tag ID "none", drawing coordinate 1 "x27j/y27j", drawing coordinate 2 "-", drawing radius "5m", area drawing color "color 3", and drawing shape "circle", as well as data for time "t7.9" of receiver ID "203", wireless tag ID "none", drawing coordinate 1 "x37j/y37j", drawing coordinate 2 "-", drawing radius "5m", area drawing color "color 3", and drawing shape "circle".

In addition, data for the receiver ID "202", wireless tag ID "R001", drawing coordinate 1 "x22aa/y22aa", drawing coordinate 2 "x21ja/y21ja", drawing radius "1m", area drawing color "color 4", and drawing shape "rounded square" at time "t2", data for the receiver ID "202", wireless tag ID "R001", drawing coordinate 1 "x22ab/y22ab", drawing coordinate 2 "-", drawing radius "-", area drawing color "color 6", and drawing shape "arrow 180 degrees" at time "t2", It includes data for receiver ID "101", wireless tag ID "R001", drawing coordinate 1 "x11fa/y11fa", drawing coordinate 2 "x11ca/y11ca", drawing radius "4m", area drawing color "Color 4", and drawing shape "Rounded square" at time "t1.5", and data for receiver ID "101", wireless tag ID "R001", drawing coordinate 1 "x11fc/y11fc", drawing coordinate 2 "-", drawing radius "-", area drawing color "Color 6", and drawing shape "Arrow 270 degrees" at time "t1.5".

The flag data 115 for generating display data shown in FIG. 17(b) indicates a situation in which the movement direction data is "not generated" and the updating receiver ID in the display data is "202."

<Method for identifying the movement direction of a subject according to the second embodiment>
Next, a method for identifying the moving direction of a subject according to embodiment 2 will be described. Fig. 18 is a diagram showing a method for identifying the moving direction of a subject according to embodiment 2. As shown in Fig. 18, consider a case where a receiver with position coordinates "x1/y1" detects the wireless tag 10 of the subject at reception point A at time "t1.1", detects the wireless tag 10 of the subject at reception point B at time "t1.2", and detects the wireless tag 10 of the subject at reception point C at time "t1.3".

The detection data for reception point A is a reception distance of "19 m" and a reception angle of "70 degrees", the detection data for reception point B is a reception distance of "18 m" and a reception angle of "90 degrees", and the detection data for reception point C is a reception distance of "18 m" and a reception angle of "120 degrees".

Using the reception distance r and reception angle θ, the position coordinate “x1′/y1′” of the reception point from the position coordinate “x1/y1” of the receiver is expressed by the following equation.
x1'=x1+r×sinθ (Formula 1)
y1′=y1+r×cosθ (Formula 2)

When the position coordinates of each reception point are calculated using (Equation 1) and (Equation 2), the position coordinates of reception point A are "x1 + 17.9/y1 + 6.5", the position coordinates of reception point B are "x1 + 18/y1", and the position coordinates of reception point C are "x1 + 15.6/y1 - 9".

When the same receiver detects the target's wireless tag 10 consecutively, the first detected reception point and the last detected reception point are adopted, and these two points are used to calculate the target's direction of movement on the receiver and the midpoint between the two points to plot the direction of movement.

When a subject moves from point P "x/y" to point Q "x'/y'", the angle φ of the movement direction and the midpoint "x''/y''" are expressed by the following equations.
φ=arctan(x'-x/y'-y) (Formula 3)
x´´=(x´+x)/2 (Formula 4)
y′′=(y′+y)/2 (Equation 5)

The position coordinates of reception point A, which is the first reception point detected, are "x1 + 17.9/y1 + 6.5", and the position coordinates of reception point C, which is the last reception point detected, are "x1 + 15.6/y1 - 9". Therefore, when the angle φ of the movement direction and the position coordinates of the midpoint are calculated using (Equation 3), (Equation 4), and (Equation 5), the angle φ is "188 degrees" and the midpoint is "x1 + 16.75/y1 - 1.25".

Display of Image Data According to Second Embodiment
Next, an example of image data 113 according to the second embodiment will be described. Fig. 19 is a diagram showing an example of image data 113 according to the second embodiment. The display data drawing unit 129 develops map data 44g on a bitmap memory, and generates, on the bitmap memory, a rounded rectangle and an arrow whose center of gravity is the midpoint calculated from drawing coordinates 1 and 2 included in the display data 114, and a circle whose center is drawing coordinate 1 and whose radius is the drawing radius, so as to be overlaid thereon, and draws each area in the corresponding color.

Specifically, as shown in FIG. 19, when the shape included in the display data 114 is a "rounded rectangle" or an "arrow", the midpoint calculated from drawing coordinate 1 and drawing coordinate 2 is set as the center of gravity, the rounded rectangle is colored 1 (e.g., blue) or color 4 (e.g., navy blue), and the arrow is colored 6 (e.g., yellow).

Furthermore, the fixed receiver 1B is color 5 (e.g. light blue), and the mobile receiver 1A is color 2 (e.g. black) and color 3 (e.g. gray). When drawing figures in the bitmap memory in which the map data 44g is expanded, they are drawn in the following order of priority: "arrow", "rounded rectangle", and "circle", and are displayed at the front of the screen in the following order of priority: "arrow", "rounded rectangle", and "circle".

<Processing procedure of the information aggregation server 100 according to the second embodiment>
Next, a description will be given of the processing procedure of the information aggregating server 100 according to the present embodiment 2. Fig. 20 to Fig. 23 are flowcharts showing the processing procedure of the information aggregating server 100 according to the present embodiment 2. As shown in the figures, when the information aggregating server 40 receives receiver position data or detection data from the fixed receiver 20 or the mobile receiver 30 (step S201; Yes), the information aggregating server 40 stores the received data in the receiver management data 111 (step S202).

If neither receiver position data nor detection data has been received from the fixed receiver 20 or mobile receiver 30 (step S201; No), or if a search request has not been received from the mobile terminal 50 (step S203; No), the process proceeds to step S201. On the other hand, if a search request has been received from the mobile terminal 50 (step S203; Yes), data within the display range is extracted from the receiver management data 111 based on the display range included in the search request, and stored in the within-display-range receiver management data 112 (step S204).

Then, data at the time immediately prior to the specified time t included in the search request is extracted from the within-display-range receiver management data 112 (step S205), the shape is set to a circle, and the position coordinates of the extracted data are included in the display data 114 as drawing coordinates 1 and the reception radius as the drawing radius (step S206).

The wireless tag ID of the target person is identified from the wireless tag management data 44a using the target person ID or searcher ID included in the search request (step S207), and the top-level data is extracted from the display data 114 (step S208).

If the wireless tag ID of the extracted data is the wireless tag ID of the subject (step S209; Yes), the area drawing color is included in the display data 114 as color 5 (step S210); if the wireless tag ID of the subject is not included (step S209; No), the area drawing color is included in the display data 114 as color 2 (step S211).

Then, the next data is extracted from the display data 114 (step S212), and if there is next data (step S213; No), the process proceeds to step S209. If there is no next data (step S213; Yes), the topmost data is extracted from the display data 114 (step S214).

Data that has the same time and receiver ID as the extracted data is identified from within the display range receiver management data 112, and the data one level above it is extracted (step S215).

If the receiver of the extracted data is a fixed receiver 20 (step S216; No), proceed to step S218. If the receiver of the data is a mobile receiver 30 (step S216; Yes), the area drawing color is set to color 3, the position coordinates of the data are included as drawing coordinates 1, and the reception radius is included as the drawing radius in the display data 114 (step S217).

An example of the display data 114 at this point is shown in Figure 24 (a). As shown in Figure 24 (a), the display data 114 associates a wireless tag ID of "none", drawing coordinate 1 of "x17j/y17j", drawing coordinate 2 of "-", drawing radius of "5m", area drawing color of "color 3", and drawing shape of "circle" with a receiver ID of "201" at time "t7.9".

Next, the data one level above the data is extracted from the display range receiver management data 112 (step S218), and if the time of the extracted data is after the time t minus the mobile receiver display setting time of the mobile receiver display setting data 44c (step S219; No), the process proceeds to step S216.

If the time of the data is earlier than the time t minus the mobile receiver display setting time (step S219; Yes), the topmost data is extracted from the display data 114, the time of the extracted data is set to t, and "not generated" is stored in the movement direction data of the display data generation flag data 115 (step S220).

The data with time t is identified from the receiver management data 112 within the display range, and the lowest-ranked data is extracted from that (step S221). If the wireless tag ID of the extracted data is the wireless tag ID of the target person (step S222; Yes), the coordinates of the received wireless tag 10 are calculated (step S223).

Next, if the receiver ID of the lowest data in the display data 114 is not the same as that of the extracted data (step S224; No), the receiver ID of the extracted data and "Already generated" are stored in the flag data 115 for generating display data (step S225), and the drawing shape is set to a circle, and the position coordinates of the received wireless tag 10 are included as drawing coordinate 1 and 1/5 of the reception radius as the drawing radius, newly in the display data 114 (step S226).

If the time of the extracted data is t (step S227; Yes), the area drawing color is included in the new display data 114 as color 1 (step S228). If the time of the data is not t (step S227; No), the area drawing color is included in the new display data 114 as color 4 (step S229).

An example of the display data 114 at this point is shown in Figure 24 (b). As shown in Figure 24 (b), the display data 114 associates the wireless tag ID "R001", drawing coordinate 1 "x38aa/y38aa", drawing coordinate 2 "-", drawing radius "1m", area drawing color "color 1", and drawing shape "circle" with the receiver ID "203" at time "t8", and the wireless tag ID "R001", drawing coordinate 1 "x22aa/y22aa", drawing coordinate 2 "-", drawing radius "1m", area drawing color "color 4", and drawing shape "circle" with the receiver ID "202" at time "t2".

Next, if the wireless tag ID of the data extracted in step S221 is not the wireless tag ID of the subject (step S222; No), the receiver ID being updated in the display data of the flag data 115 for generating display data is compared with the receiver ID of the extracted data (step S230). If the comparison results are the same (step S230; Yes), the receiver ID being updated in the display data of the flag data 115 for generating display data is cleared (step S231), and the process proceeds to step S232. If the comparison results are different (step S230; No), the process proceeds to step S232.

Next, in the comparison in step S224, if the receiver ID of the lowest data in the display data 114 is the same as that of the extracted data (step S224; Yes), and the movement direction data of the flag data 115 for generating display data is "not generated" (step S235; Yes), or the receiver ID being updated in the display data of the flag data 115 for generating display data is not the same as the receiver ID of the extracted data (step S236; No), proceed to step S225.

In addition, if the comparison in step S224 finds that the receiver ID of the lowest data in the display data 114 is the same as that of the extracted data (step S224; Yes), and the movement direction data of the flag data 115 for generating display data is not "not generated" (step S235; No), and the receiver ID being updated in the display data of the flag data 115 for generating display data is the same as that of the extracted data (step S236; Yes), then the shape of the lowest data in the display data 114 is confirmed (step S237).

If the shape of the lowest-level data in the display data 114 is a circle (step S237; Yes), the shape of the lowest-level data in the display data 114 is changed to a rounded rectangle, and the position coordinates of the received wireless tag 10 are included in the display data 114 as drawing coordinates 2 (step S238).

The midpoint and angle between the two points are calculated using the drawing coordinate 1 and drawing coordinate 2 of that data (step S239). The time of that data is set as the time, the midpoint as drawing coordinate 1, the drawing shape as an arrow and angle, and the area drawing color as color 6, and these are newly included in the display data 114 (step S240), and the process proceeds to step S232.

An example of the display data 114 at this point is shown in Figure 24 (c). As shown in Figure 24 (c), the display data 114 associates the wireless tag ID "R001", drawing coordinate 1 "x22aa/y22aa", drawing coordinate 2 "x21ja/y21ja", drawing radius "1m", area drawing color "color 4", and drawing shape "rounded square" with the receiver ID "202" at time "t2". This is an update of drawing coordinate 2 and drawing shape for the data associated with the receiver ID "202" at time "t2" in the example of the display data 114 shown in Figure 24 (b) (step S238).

The display data 114 shown in FIG. 24(c) associates the wireless tag ID "R001", drawing coordinate 1 "x22ab/y22ab", drawing coordinate 2 "-", drawing radius "-", area drawing color "color 6", and drawing shape "arrow 180 degrees" with the receiver ID "202" at time "t2". This is data newly included in the display data 114 in step S240.

Next, in checking the shape of the lowest data in the display data 114 in step S237, if the shape of the data is not a circle (step S237; No), the position coordinates of the received wireless tag 10 are included in the display data 114 as drawing coordinates 2 in the data one level above the lowest data in the display data 114 (step S241).

The midpoint and angle between the two points are calculated using the drawing coordinate 1 and drawing coordinate 2 of the data (step S242). The midpoint is set as drawing coordinate 1, and the shape is an arrow with angle, and included in the lowest data in the display data 114 (step S243), and the process proceeds to step S232.

An example of the display data 114 at this point is shown in Figure 24 (c). As shown in Figure 24 (c), the display data 114 associates the wireless tag ID "R001", drawing coordinate 1 "x11fa/y11fa", drawing coordinate 2 "x11ca/y11ca", drawing radius "4m", area drawing color "color 4", and drawing shape "rounded square" with the receiver ID "101" at time "t1.5". This is after drawing coordinate 2 has been updated in step S241.

The display data 114 shown in FIG. 24(c) associates the wireless tag ID "R001", drawing coordinate 1 "x11fc/y11fc", drawing coordinate 2 "-", drawing radius "-", area drawing color "Color 6", and drawing shape "Arrow 270 degrees" with the receiver ID "101" at time "t1.5". This is the result of updating drawing coordinate 1 and drawing shape in step S243.

Next, in step S232, data one level above the extracted data is extracted from the within-display-range receiver management data 112 (step S232), and if the time of the extracted data is after the time t minus the detection information display setting time of the detection information display setting data 44d (step S233; No), the process proceeds to step S222.

If the time of the data is earlier than the time t minus the detection information display setting time (step S233; Yes), image data 113 is generated from the display data 114 and map data 44g and transmitted to the mobile device 50 (step S234), and the process ends.

<Display Example of Image Data 113 According to Second Embodiment>
Next, a description will be given of an example of the display of the image data 113 according to the second embodiment. Figures 25 to 27 are diagrams showing an example of the display of the image data 113 according to the second embodiment.

Figure 25 is an example display at time t2. The figure drawn over the detection area of the mobile receiver 2A is a rounded rectangle in color 1, indicating that the wireless tag 10 has been detected and that its movement direction is 290 degrees. The figure drawn over the detection area of the fixed receiver 3B is a rounded rectangle in color 4, indicating that the subject moved in the 180 degree direction between the time obtained by subtracting the detection information display setting time from time t2 and time t2.

Figure 26 is an example display at time t3. The figure drawn over the detection area of the mobile receiver 3A is a rounded rectangle in color 1, indicating that the wireless tag 10 has been detected and that its movement direction is 170 degrees. The figures drawn over the detection areas of the fixed receiver 3B and the mobile receiver 2A are rounded rectangles in color 4, indicating that the subject moved in the direction of the arrow between the time obtained by subtracting the detection information display setting time from time t2 and time t2.

Figure 27 is an example display at time t9. Each receiver is colored 2, indicating that it is not detecting the wireless tag 10. Note that the figures drawn superimposed on the detection areas of fixed receiver 1B, fixed receiver 2B, and fixed receiver 3B, as well as the figures drawn in two locations near intersection c, are rounded rectangles colored 4, indicating that the subject moved in the direction of the arrow between the time obtained by subtracting the detection information display setting time from time t2 and time t2.

In this way, the search support system according to the second embodiment allows the searcher to narrow down the search area by providing the area and movement direction in which the target person was present within a certain period of time (T2) up to time t2.

In the above-mentioned second embodiment, the generation of display data related to the movement direction of the subject is described as being performed by extracting corresponding data in time series from the receiver management data 112 within the display range. However, the present invention is not limited to this, and it is also possible to configure the system so as to extract corresponding data for each receiver and generate display data related to the movement direction of the subject.

Specifically, the receiver IDs included in the within-display-range receiver management data 112 are stored in the receiver list data without duplication. The top-level receiver ID in the receiver list data is extracted, and detection data for the target wireless tag ID associated with that receiver ID is extracted from the within-display-range receiver management data 112, and display data 114 relating to a circle or rounded-corner square shape is generated. This process is performed for all receiver IDs in the receiver list data.

Next, data with rounded rectangular shapes is extracted from the display data 114, the direction (angle) of movement of the subject is calculated from the drawing coordinates 1 and 2 of that data, and display data 114 with an arrow/angle shape is generated. This process is performed on all data with rounded rectangular shapes in the display data 114.

In this way, by extracting the relevant data for each receiver from the within-display-range receiver management data 112 and generating display data related to the target person's movement direction, and providing the area in which the target person was present and the direction of movement, the searcher can narrow down the search range.

[Embodiment 3]
In the above-mentioned first and second embodiments, the case where the area where the subject was present within a certain period of time (T2) in the past up to time t2 is clarified is described, but the present invention is not limited to this, and it is also possible to configure to provide information predicting the area where the subject is likely to be present from the present time onwards. Therefore, in the present third embodiment, the case where information predicting the area where the subject is likely to be present from the present time onwards is provided is described.

<Outline of search support system according to embodiment 3>
First, an overview of the search support system according to the third embodiment will be described. Fig. 28 is an explanatory diagram for explaining the overview of the search support system according to the third embodiment. As shown in Fig. 28, the position coordinates, moving speed and moving direction of the detected wireless tag 10 are stored using the display range receiver management data 112 (S21). Here, when the same receiver continuously detects the wireless tag 10 of the target person, the first detected reception point and the last detected reception point are adopted, and the moving speed is calculated from the time of these two points and the position coordinates of the wireless tag.

For example, if the reception point where the wireless tag 10 was first detected is at position coordinates "x1/y1" at time "t1" and the reception point where it was last detected is at position coordinates "x2/y2" at time "t2", then the velocity v is expressed by the following equation.
v=SQRT((x2-x1)^2+(y2-y1)^2)/(t2-t1) (Formula 6)
Here, "SQRT" represents the square root and "^2" represents the square.

Using the accumulated data, the predicted moving speed, predicted moving direction, and probability density function are calculated by statistical processing (S22), and the areas where the subject is highly likely to be present at the next sampling time are predicted (S23). Here, the areas indicated by colors 7, 8, and 9 indicate areas where the subject is highly likely to be present at the next sampling time.

Specifically, the predicted moving speed is the average value for the entire section weighted by a short-term scalar value. The weighting is such that the most recent data at the time of prediction is given a high weight. This is because walking speed is generally thought to change over a relatively short period of time depending on momentary mood, fatigue over time, the surrounding scenery, and other environmental conditions.

The predicted movement direction is the average of the movement direction angles weighted to short-term or long-term values. When the destination position is clear, the weighting is done by treating the movement vector as a long-term movement vector starting from the detection start point, and calculating the average and variance. This is because there is little fluctuation in the global direction, making it easier to narrow down the direction.

When the destination position is unclear, weighting is performed by weighting the most recent value of the direction angle of the short-term movement vector and calculating the average. This is because the more irregular the walking, the more difficult it is to narrow down the direction, and conversely, it is important to display a wide range of variation.

The direction of movement can also be predicted by calculating the average value of the long-term vector as the mean value and the variance of the short-term vector as the variance. This is because it makes it possible to narrow down the target direction while displaying a wide range of variation.

In addition, when displaying the probability density function, it can be displayed in a different color corresponding to each of the two types of prediction methods related to the direction of movement, or it can be configured to select one of them and display it.

The predicted location probability density function is calculated by using the predicted movement speed and predicted movement direction as the average value and a constant value as the variance value. Furthermore, the predicted location probability density function is multiplied by a presence tendency density function that sets a high presence tendency on roads and a low presence tendency off roads, and the probability density function is calculated by excluding areas where the receiver does not detect the presence of the wireless tag 10.

Assuming that the scalar velocity and direction angle follow a normal distribution or a von Mises distribution, respectively, the probability density function is used to predict the area where the subject is likely to be present at the next sampling time. The distribution can also be configured to be determined by machine learning.

<Display procedure using probability density function according to the third embodiment>
Next, a display method using the probability density function according to the present embodiment 3 will be described. Fig. 29 is a diagram for explaining a display method using the probability density function according to the present embodiment 3. First, as shown in Fig. 29(a), a probability density function is used to represent each position coordinate as a probability density function map.

Specifically, the probability density function indicates that for a position coordinate of "X coordinate 1/y", when y is the Y coordinate 1, it is "0.0162", when y is the Y coordinate 2, it is "0.0187", when y is the Y coordinate 3, it is "0.0201", when y is the Y coordinate 4, it is "0.0192", when y is the Y coordinate 5, it is "0.0149", when y is the Y coordinate 6, it is "0.0085", and when y is the Y coordinate 7, it is "0.0034".

In addition, for position coordinates of "X coordinate 2/y", if y is the Y coordinate 1, it is "0.0106", if y is the Y coordinate 2, it is "0.0169", if y is the Y coordinate 3, it is "0.0212", if y is the Y coordinate 4, it is "0.0234", if y is the Y coordinate 5, it is "0.0157", if y is the Y coordinate 6, it is "0.0156", and if y is the Y coordinate 7, it is "0.0051".

In addition, for position coordinates of "X coordinate 3/y", if y is the Y coordinate 1, it is "0.0085", if y is the Y coordinate 2, it is "0.0089", if y is the Y coordinate 3, it is "0.0129", if y is the Y coordinate 4, it is "0.0200", if y is the Y coordinate 5, it is "0.0250", if y is the Y coordinate 6, it is "0.0214", and if y is the Y coordinate 7, it is "0.0116".

In addition, for position coordinates of "X coordinate 4/y", if y is the Y coordinate 1, it is "0.0021", if y is the Y coordinate 2, it is "0.0027", if y is the Y coordinate 3, it is "0.0042", if y is the Y coordinate 4, it is "0.0143", if y is the Y coordinate 5, it is "0.0165", if y is the Y coordinate 6, it is "0.0240", and if y is the Y coordinate 7, it is "0.0103".

In addition, for a position coordinate of "X coordinate 5/y", if y is the Y coordinate 1, it is "0.0009", if y is the Y coordinate 2, it is "0.0004", if y is the Y coordinate 3, it is "0.0035", if y is the Y coordinate 4, it is "0.0115", if y is the Y coordinate 5, it is "0.0219", if y is the Y coordinate 6, it is "0.0242", and if y is the Y coordinate 7, it is "0.0156".

In addition, for position coordinates of "X coordinate 6/y", if y is the Y coordinate 1, it is "0.0012", if y is the Y coordinate 2, it is "0.0019", if y is the Y coordinate 3, it is "0.0035", if y is the Y coordinate 4, it is "0.0128", if y is the Y coordinate 5, it is "0.0153", if y is the Y coordinate 6, it is "0.0227", and if y is the Y coordinate 7, it is "0.0098".

In addition, for position coordinates of "X coordinate 7/y", if y is the Y coordinate 1, it is "0.0053", if y is the Y coordinate 2, it is "0.0062", if y is the Y coordinate 3, it is "0.0099", if y is the Y coordinate 4, it is "0.0166", if y is the Y coordinate 5, it is "0.0218", if y is the Y coordinate 6, it is "0.0192", and if y is the Y coordinate 7, it is "0.0106".

Next, the drawing map in Figure 29 (b) will be described. The drawing map is created by extracting position coordinates where the probability density function map value is 0.0150 or more, drawing position coordinates of 0.0240 or more in color 7 (e.g. dark green), position coordinates of 0.0200 or more and less than 0.240 in color 8 (e.g. green), and position coordinates of 0.0150 or more and less than 0.200 in color 9 (e.g. light green).

<Display example of image data 113 according to the third embodiment>
Next, an example of the display of the image data 113 according to the present embodiment 3 will be described. Fig. 30 is a diagram showing an example of the display of the image data 113 according to the present embodiment 3. Fig. 30 is a display example at time t3, which is obtained by adding an area where the subject is highly likely to be present at the next sampling time, calculated using a probability density function, to the display example at t3 according to the embodiment 2 (Fig. 26).

Areas with a high probability of the subject's location at the next sampling time are shown in colors 7, 8, and 9. This display example shows that there is an area with a high probability of the subject being present at the next sampling time, centered along the road 180 degrees from the position of the mobile receiver 3A.

In this way, the search support system according to the third embodiment can provide information that predicts the area in which the subject is likely to be located from the present time onward.

Note that the configurations illustrated in the above embodiments are merely functional schematics, and do not necessarily have to be physically configured as illustrated. In other words, the form of distribution and integration of each device is not limited to that illustrated, and all or part of the devices can be functionally or physically distributed and integrated in any unit depending on various loads, usage conditions, etc.

The search support system and search support method of the present invention are suitable for efficiently securing a target person.

1A, 2A, 3A, 30 Mobile receiver 1B, 2B, 3B, 20 Fixed receiver 10 Wireless tag 40 Information aggregation server 41 Display unit 42 Input unit 43 Communication unit 44 Memory unit 44a Wireless tag management data 44b Receiver management data 44c Mobile receiver display setting data 44d Detection information display setting data 44e Display range receiver management data 44f Image data 44g Map data 44h Display data 45 Control unit 45a Wireless tag management unit 45b Receiver management unit 45c Display setting unit 45d Image data generation unit 45e Display range data extraction unit 45f Current information processing unit 45g Mobile receiver past information processing unit 45h Past detection information processing unit 45i Image data notification unit 45j Display data drawing unit 50 Mobile terminal 100 Information aggregation server 110 Memory unit REFERENCE SIGNS LIST 111 Receiver management data 112 Display range receiver management data 113 Image data 114 Display data 115 Flag data for generating display data 120 Control unit 121 Receiver management unit 122 Image data generation unit 123 Display range data extraction unit 124 Current information processing unit 125 Detailed detection information processing unit 126 Coordinate calculation unit 127 Display data change processing unit 128 Movement direction calculation unit 129 Display data drawing unit

Claims (7)

A search support system having a terminal device of a search requester who requests a search for a person who is a search target, a search information providing device that provides information related to the person to the terminal device, a wireless tag carried by the person, and a receiver that cooperates in the search for the person,
The receiver includes :
When the tag information of the wireless tag is detected , the search information providing device is notified of detection information including the detected tag information, the detection time of the tag information, the position information of the device itself, and the distance and angle from the position of the device itself to the wireless tag ;
The search information providing device includes:
a storage means for storing within-display-range receiver management data including the position information of the receiver generated based on detection information notified from the receiver, a radio tag signal receivable radius, and an ID of the radio tag when the receiver detects the radio tag;
a first calculation means for calculating a coordinate range of an area where the subject exists and an angle of a moving direction from a coordinate range of an area where the subject exists obtained based on a radio tag signal receivable radius of the receiver at a predetermined time point, the coordinates where the receiver exists at the predetermined time point, and the coordinates where the receiver existed in the past going back a predetermined time interval from the predetermined time point;
a storage means for storing in said storage means display data that stores a coordinate range of an area in which said subject was present within a certain period of time in the past up to said predetermined time point, which is obtained as an output of said first calculation means, and an angle of said moving direction;
a notification means for notifying the terminal device of the contents of the display data;
Equipped with
The terminal device
A display means is provided for displaying on a map, based on the contents of the display data, the area in which the subject was present within a certain period of time up to the specified time point and the angle of the direction of movement of the subject, in the form of an arrow having a width based on the radius of radio tag signal reception of the receiver.
A search support system comprising: The search information providing device includes:
storing a presence tendency density function map in the storage means, the presence tendency information representing the degree of the presence tendency of pedestrians in the area being stored as a probability value for each position coordinate;
a storage means for storing time-series information of the position coordinates, the moving speed and the moving direction of the wireless tag in the storage means;
a generating means for generating a predicted position probability density function map by performing statistical processing on the time series information stored in the storage means;
a second calculation means for calculating a probability density function from the existence tendency density function map and the predicted position probability density function map;
Further equipped with
The display means is
The information regarding the area where the subject is likely to be present from the predetermined time point onward is displayed on a map in a color-coded format based on the value of each area obtained as an output of the second calculation means.
2. The search support system according to claim 1, 3. The search support system according to claim 2, wherein the statistical processing determines an average value and a variance value and reflects them in the predicted position probability density function map. 4. The search support system according to claim 3, wherein the statistical processing is performed by giving a high weight to data immediately before the time of prediction. The search support system according to claim 4, characterized in that in the statistical processing, the predicted movement speed is calculated as an average value for the entire section weighted by a short-term scalar value, and the predicted movement direction is calculated as an average value of a movement direction angle weighted by a short-term or long-term value. 6. A search support system according to claim 5, wherein in the statistical processing, an average value of the predicted movement direction is calculated as an average value of a long-term vector, and a variance value is calculated as a variance value of a short-term vector. A search support method in a search support system having a terminal device of a search requester requesting a search for a person who is a search target, a search information providing device that provides information related to the person to the terminal device, a wireless tag carried by the person, and a receiver that cooperates in the search for the person, comprising:
a notification step of notifying the search information providing device of detection information including the detected tag information, the detection time of the tag information, the position information of the own device, and the distance and angle from the position of the own device to the wireless tag , when the receiver detects the tag information of the wireless tag;
a storage step in which the search information providing device stores in a storage unit, within-display-range receiver management data including the position information of the receiver, the radio tag signal receivable radius, and the ID of the radio tag when the receiver detects the radio tag, the data being generated based on the detection information notified from the receiver;
a first calculation step in which the search information providing device calculates a coordinate range of an area in which the subject exists and an angle of a moving direction from a coordinate range of an area in which the subject exists, which is obtained based on a radio tag signal receivable radius of the receiver at a predetermined time point, the coordinates at which the receiver exists at the predetermined time point, and the coordinates at which the receiver existed in the past going back a predetermined time interval from the predetermined time point;
a first storage step in which the search information providing device stores in the storage unit display data that stores the range of coordinates of an area in which the subject was present within a certain period of time in the past up to the predetermined time point, the range being obtained as an output of the first calculation step, and an angle of the moving direction;
a second notification step of the search information providing device notifying the terminal device of the content of the display data;
a display step in which the terminal device displays, based on the contents of the display data, the area in which the subject person was present within a certain period of time up to the predetermined time point and the angle of the moving direction on a map in the form of an arrow having a width based on the radius of radio tag signal reception of the receiver;
A search support method comprising:

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