JP2018182436A - Terminal device, radio communication system comprising the same, program to be executed by computer, and computer-readable storage medium recording program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a terminal device capable of uploading sensing results to a server while reducing load on a communication network.SOLUTION: A sensor 15 detects sensor data and outputs the detected sensor data to a control unit 14, and a GPS 16 detects the position of a terminal device 10 and outputs it to the control unit 14. The control unit 14 associates time information at the time of receiving the sensor data from the sensor 15 and the position information with the sensor data, and stores these associated data in a storage unit 17. The control unit 14 reads the sensor data from the storage unit 17, determines sensor data with a degree of confidence above a threshold among the read sensor data, and outputs the determined sensor data to a communication unit 13. The communication unit 13 transmits the sensor data received from the control unit 14 to a server via an antenna 12.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a terminal device, a wireless communication system including the same, a program for causing a computer to execute, and a computer readable recording medium storing the program.

  By sensing the temperature and humidity, the degree of air pollution, the availability of frequencies, etc. with a large number of sensors over a wide area, it can be used for weather forecasting, air pollution surveys, installation plans of wireless base stations, and the like.

  However, installing a large number of devices equipped with sensors over a wide area requires a great deal of cost for installation and maintenance of the devices, resulting in a large barrier to realization.

  Therefore, focusing on mobile terminals such as smartphones carried by humans and performing sensing using sensors mounted on those terminals, it is called participatory sensing or cloud sensing that realizes wide-area sensing at relatively low cost. One form of sensing has recently been proposed and is beginning to be used.

  As participatory sensing, those described in Patent Documents 1 and 2 are known. In this participatory sensing, it is conceivable to use cellular communication (for example, LTE: Long Term Evolution) in order to upload data sensed by each terminal to a server.

Unexamined-Japanese-Patent No. 2015-200862 JP, 2014-013556, A

  However, in order to achieve wide-area sensing, many terminals are required, and uploading data sensed by many terminals to a server has a problem that the cellular communication is heavily loaded.

  Therefore, according to the embodiment of the present invention, there is provided a terminal device capable of uploading a sensing result to a server while reducing the load on the communication network.

  Further, according to the embodiment of the present invention, there is provided a wireless communication system including a terminal device capable of uploading a sensing result to a server while reducing load on the communication network.

  Furthermore, according to the embodiment of the present invention, a program for reducing the load on the communication network and causing the computer to execute uploading of the sensing result to the server is provided.

  Furthermore, according to the embodiment of the present invention, there is provided a computer readable recording medium recording a program for causing a computer to execute uploading of sensing results to a server by reducing load on a communication network.

(Configuration 1)
According to the embodiment of the present invention, the terminal device includes the sensor, the processing means, and the transmission means. The sensor detects sensor data. The processing means performs a determination process of determining, as sensor data to be transmitted to the server, sensor data whose reliability of the sensor data is equal to or higher than a threshold among the detected sensor data. The transmitting means transmits the determined sensor data to the server.

  According to configuration 1, the terminal device transmits, to the server, sensor data whose reliability is equal to or higher than the threshold value among the detected sensor data.

  Therefore, the load on the communication network can be reduced and sensor data can be uploaded to the server.

(Configuration 2)
In Configuration 1, the processing unit aggregates a plurality of sensor data when there are a plurality of sensor data whose reliability of the sensor data is equal to or more than a threshold. The transmitting means transmits the aggregated sensor data to the server.

  According to configuration 2, the number of sensor data transmitted to the server is reduced.

  Therefore, the amount of data can be reduced compared to the case where each terminal device transmits all of the plurality of detected sensor data to the server.

(Configuration 3)
In Configuration 1, when the terminal device on which the processing unit is mounted receives sensor data from another terminal device, the processing unit determines the reliability of the sensor data received from the other terminal device, and the sensor data detected by the sensor. A sum of reliability is calculated, and when the calculated sum is equal to or greater than a threshold value, sensor data received from another terminal device and sensor data detected by the sensor are aggregated. The transmitting means transmits the aggregated sensor data to the server.

  According to configuration 3, the number of terminal devices that transmit sensor data to the server is reduced, and the number of sensor data transmitted to the server is reduced.

  Therefore, the load on the communication network can be further reduced.

(Configuration 4)
In Configuration 3, when the rank of the terminal device on which the self terminal is mounted is higher than the ranks of other terminal devices, the transmission means transmits the aggregated sensor data to the server.

  According to configuration 4, the number of terminal devices that transmit sensor data to the server is reduced.

  Thus, the load on the communication network can be reduced.

(Configuration 5)
In Configuration 1, sensor data is defined by position information indicating a detected position and time information indicating a detected time. The processing means uses, as the reliability of the sensor data, a weighted sum of the position reliability indicating the reliability of the position at which the sensor data is detected and the time reliability indicating the reliability of the time at which the sensor data is detected. Perform the decision process.

  According to configuration 5, the reliability of the sensor data is determined based on the position and time at which the sensor data is detected.

  Therefore, the reliability can be uniquely determined even for a plurality of sensor data, and the sensor data to be transmitted to the server can be easily determined.

(Configuration 6)
In configuration 5, the position reliability at a certain position decreases as the distance to the position of the sensor data detected by the sensor increases, and increases as the distance to the position of the sensor data detected by the sensor decreases.

  Also, the time reliability at a certain time decreases as the absolute value of the difference from the sensor data detected by the sensor increases, and the absolute value of the difference from the sensor data detected by the sensor decreases. According to

  According to the configuration 6, with respect to the position and time of the sensor data to be detected, in the position and time close thereto, the reliability of the sensor data becomes high and the possibility of being transmitted to the server increases.

  Therefore, position and near-time sensor data can be collected.

(Configuration 7)
Further, according to the embodiment of the present invention, the wireless communication system includes a terminal device and a server. The terminal device includes the terminal device according to any one of Configurations 1 to 6. The server receives sensor data from the terminal device and holds the received sensor data.

  According to configuration 7, it is possible to reduce the communication load when the terminal device uploads sensor data to the server.

(Configuration 8)
Furthermore, according to the embodiment of the present invention, the program causes the processing means to transmit to the server the sensor data whose reliability of the sensor data is equal to or higher than the threshold among the sensor data detected by the sensor. A first step of performing determination processing to determine
The transmitting means is a program for causing the computer to execute the second step of transmitting a part of the sensor data determined in the first step to the server.

  According to the configuration 8, by causing the computer to execute the program, sensor data having a reliability higher than or equal to the threshold among the detected sensor data is transmitted to the server.

  Therefore, the load on the communication network can be reduced and sensor data can be uploaded to the server.

(Configuration 9)
In Configuration 8, the processing means, in the first step, aggregates a plurality of sensor data when there are a plurality of sensor data whose reliability of the sensor data is equal to or greater than a threshold. In the second step, the transmitting means transmits the aggregated sensor data to the server.

  According to configuration 9, by causing the computer to execute the program, the number of sensor data to be transmitted to the server is reduced.

  Therefore, the amount of data can be reduced compared to the case where each terminal device transmits all of the plurality of detected sensor data to the server.

(Configuration 10)
In the configuration 8, when the terminal device on which the processing device is mounted receives sensor data from the other terminal device in the first step, the processing means determines the reliability of the sensor data received from the other terminal device by the sensor The sum of the reliability of the detected sensor data is calculated, and when the calculated sum is equal to or greater than the threshold value, sensor data received from another terminal device and sensor data detected by the sensor are aggregated. In the second step, the transmitting means transmits the aggregated sensor data to the server.

  According to configuration 10, by causing the computer to execute the program, the number of terminal devices transmitting sensor data to the server is reduced, and the number of sensor data transmitted to the server is reduced.

  Therefore, the load on the communication network can be further reduced.

(Configuration 11)
In configuration 10, in the second step, the transmitting means transmits the aggregated sensor data to the server when the rank of the terminal device mounted with itself is higher than the rank of the other terminal devices.

  According to the configuration 11, by causing the computer to execute the program, the number of terminal devices that transmit sensor data to the server is reduced.

  Thus, the load on the communication network can be reduced.

(Configuration 12)
In configuration 8, sensor data is defined by position information indicating a detected position and time information indicating a detected time. In the first step, the processing means includes a sensor that is a weighted sum of a position reliability indicating the reliability of the position at which the sensor data is detected and a time reliability indicating the reliability of the time at which the sensor data is detected. It performs decision processing using it as the reliability of data.

  According to configuration 12, by causing the computer to execute the program, the reliability of the sensor data is determined based on the position and time at which the sensor data is detected.

  Therefore, the reliability can be uniquely determined even for a plurality of sensor data of different types, and the sensor data to be transmitted to the server can be easily determined.

(Configuration 13)
In configuration 12, the position reliability at a certain position decreases as the distance to the position of the sensor data detected by the sensor increases, and increases as the distance to the position of the sensor data detected by the sensor decreases. Also, the time reliability at a certain time decreases as the absolute value of the difference from the sensor data detected by the sensor increases, and the absolute value of the difference from the sensor data detected by the sensor decreases. According to

  According to the configuration 13, by causing the computer to execute the program, with respect to the position and time of the sensor data to be detected, in the position and time close thereto, the sensor data becomes highly reliable and is transmitted to the server The possibilities increase.

  Therefore, position and near-time sensor data can be collected.

(Configuration 14)
Furthermore, a recording medium according to the embodiment of the present invention is a computer readable recording medium recording the program according to any one of constitution 8 to constitution 13.

  Sensor data can be uploaded to the server with reduced load on the network.

FIG. 1 is a schematic view of a wireless communication system according to an embodiment of the present invention. It is the schematic of the terminal device shown in FIG. It is the schematic of the server shown in FIG. It is a conceptual diagram which shows the preservation | save format of sensor data. It is a conceptual diagram of a cell. It is a conceptual diagram of a time slot. It is a figure for demonstrating the reliability function of sensor data. It is a figure which shows the example of a reliability function. It is a figure for demonstrating in detail the effective range of sensor data. It is a diagram illustrating a block of sensor data r _i exists. It is a figure which shows the reliability of the block to which sensor data belong. It is a figure which shows the reliability of the block to which sensor data belong. It is a figure which shows the total result which totaled the calculation result of reliability. It is a figure which shows the example of the aggregation method of sensor data. It is a figure which shows the kind of communication between terminals. It is a conceptual diagram of communication between terminals. It is a figure which shows the flowchart for demonstrating operation | movement of terminal device p, q and the server 60. FIG. It is a figure which shows the flowchart for demonstrating the intensive process of sensor data. FIG. 19 is a diagram showing a flowchart for explaining the detailed operation of step S21 shown in FIG. 18; FIG. 19 is a diagram showing a flowchart for explaining the detailed operation of step S22 shown in FIG. 18; FIG. 19 is a diagram showing a flowchart for explaining another detailed operation of step S22 shown in FIG. 18; It is a figure which shows the flowchart for demonstrating the transmission operation of a Hello packet. It is a figure which shows the flowchart for demonstrating the operation | movement of the receiving side terminal of a Hello packet, and a transmitting side terminal. It is a figure which shows the flowchart for demonstrating the detailed operation | movement of FIG.23 S46. FIG. 25 is a diagram showing a flowchart for describing the detailed operation of step S462 shown in FIG. 24.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding portions are denoted by the same reference characters and description thereof will not be repeated.

  FIG. 1 is a schematic view of a wireless communication system according to an embodiment of the present invention. Referring to FIG. 1, a wireless communication system 100 according to the embodiment of the present invention includes terminal devices 1 to 10, wireless base stations 20, 30, 40, a network 50, and a server 60.

  The terminal devices 1 to 10 and the radio base stations 20, 30, 40 are disposed in the radio communication space.

  Each of the terminal devices 1 to 10 includes, for example, a smartphone, a mobile phone, a wearable device, a communication device fixed at a predetermined position, and the like, and participates in type sensing that detects sensor data using a sensor mounted on itself. It is a terminal device to perform.

  Each of the terminal devices 1 to 10 may be moved by a person, for example, may be installed and moved in a vehicle such as a bus or a private car.

  Then, the user of the terminal devices 1 to 10 may cause the terminal devices 1 to 10 to participate in the wireless communication system 100 by volunteering, or receive some reward to cause the terminal devices 1 to 10 to participate in the wireless communication system 100 It is also good.

  By doing this, compared to the case where a fixed sensor is installed for sensing with respect to the environment, the cost due to the installation or operation of the sensor can be reduced, and sensor data can be sensed in a wide range as a person moves. .

  Further, each of the terminal devices 1 to 10 has a function of performing wireless communication using a short range wireless communication system, and a wireless communication system different from the short range wireless communication system (in the embodiment of the present invention, “wireless server for server And transmitting the sensor data to the server 60 via the wireless base station (any of the wireless base stations 20, 30, 40).

  The short distance wireless communication system is, for example, Bluetooth (registered trademark) LE (Low Energy), WiFi Direct, or the like. However, the short-distance wireless communication system is not limited to these, and any wireless communication system may be used as long as it can wirelessly communicate between the terminal devices 1 to 10.

  The server wireless communication system is generally a wireless communication system capable of performing wireless communication between the terminal devices 1 to 10 and the server 60 via the network 50. The server wireless communication system is, for example, LTE, W-CDMA (Wideband Code Division Multiple Access), or the like. However, the server wireless communication system is not limited to these, and any wireless communication system can be used as long as it can wirelessly communicate between the terminal devices 1 to 10 and the server 60 via the network 50. It may be.

  Each of the terminal devices 1 to 10 is assigned a rank Rk. Therefore, each of the terminal devices 1 to 10 holds the rank Rk.

  Each of the terminal devices 1 to 10 periodically broadcasts a Hello packet including its own address and the rank Rk using the short distance wireless communication system.

Each of the terminal devices 1 to 10 detects, for example, air temperature, humidity, air pressure, CO ₂ , PM 2.5, illuminance, ultraviolet light intensity, noise, radio frequency and the like, and the detected air temperature and humidity as sensor data Hold.

  Each of the terminal devices 1 to 10 detects the position and time when the sensor data is detected, and holds position information indicating the detected position and time information indicating the detected time in association with the sensor data Do.

  Then, each of the terminal devices 1 to 10 transmits a part of the detected sensor data, position information and time information to the server 60 using the server wireless communication system based on the reliability of the sensor data by a method described later. Send.

  Also, each of the terminal devices 1 to 10 receives the Hello packet from another terminal device, and detects the other terminal device by detecting an address included in the received Hello packet. Then, when each of the terminal devices 1 to 10 detects another terminal device, the sensor data, the position information and the time information detected by itself are transmitted to the other terminal device using a short distance wireless communication system by a method described later. It transmits or receives sensor data, position information and time information detected by another terminal device from the other terminal device using the short distance wireless communication system.

  A terminal device that has received sensor data and the like from another terminal device through inter-terminal communication described later determines whether it is possible to combine sensor data detected by itself and sensor data received from another terminal device. .

  Then, when it is determined that the sensor data can be aggregated, the terminal device that has received the sensor data and the like from another terminal device aggregates the plurality of sensor data by a method described later.

  When the plurality of sensor data are aggregated, each of the terminal devices 1 to 10 transmits the aggregated sensor data, position information, and time information to the server 60 using the server wireless communication system.

  Each of the radio base stations 20, 30, 40 is connected to the network 50. The wireless base stations 20, 30, 40 may perform wireless communication by the same server wireless communication system, or may perform wireless communication by different server wireless communication systems.

  Each of the wireless base stations 20, 30, 40 receives sensor data, position information and time information from the terminal device (at least one of the terminal devices 1 to 10) using the server wireless communication system and receives the sensor data, position information and time information Sensor data, position information and time information are transmitted to the server 60 via the network 50.

  The server 60 receives sensor data, position information and time information from the radio base station (at least one of the radio base stations 20, 30, 40) via the network, and the received sensor data, position information and time information Hold.

  FIG. 2 is a schematic view of the terminal device 1 shown in FIG. Referring to FIG. 2, the terminal device 1 includes antennas 11 and 12, a communication unit 13, a control unit 14, a sensor 15, a GPS (Global Positioning System) 16, and a storage unit 17.

  The communication unit 13 receives the Hello packet from another terminal apparatus via the antenna 11, and outputs the received Hello packet to the control unit 14.

  The communication unit 13 receives a Hello packet including the address of the terminal device 1 and the rank Rk from the control unit 14 and broadcasts the received Hello packet via the antenna 11 using the short distance wireless communication system.

  The communication unit 13 receives the packet PKT_1 including sensor data and the like from the control unit 14, and transmits the received packet PKT_1 to the destination terminal apparatus via the antenna 11 using the short-range wireless communication system.

  The communication unit 13 receives the packet PKT_1 from another terminal apparatus via the antenna 11 using the short distance wireless communication system, and outputs the received packet PKT_1 to the control unit 14.

  The communication unit 13 receives the packet PKT_2 including the collected sensor data from the control unit 14, and transmits the received packet PKT_2 to the server 60 via the antenna 12 using the server wireless communication system.

  The control unit 14 incorporates a timer. The control unit 14 holds the address of the terminal device 1 and the rank Rk assigned to the terminal device 1.

  When it is time to detect sensor data, the control unit 14 controls the sensor 15 to detect the sensor data, and controls the GPS 16 to detect the position.

  When the control unit 14 receives sensor data from the sensor 15 and receives position information indicating the position of the terminal device 1 from GPS, the control unit 14 detects the time when the sensor data and the position information are received. Then, the control unit 14 stores the sensor data, the position information, and the time information indicating the time in the storage unit 17 in association with each other.

  The control unit 14 receives the Hello packet from the communication unit 13, and detects the address and the rank Rk from the received Hello packet. Then, based on the detected address, the control unit 14 detects another terminal device capable of wireless communication with the terminal device 1 using the short distance wireless communication system. Thereby, the control unit 14 detects another terminal device that has encountered the terminal device 1.

  In addition, the control unit 14 determines whether to transmit the sensor data detected by the terminal device 1 to another terminal device based on the detected rank Rk. More specifically, when the rank Rk detected from the Hello packet is larger than the rank Rk of the terminal device 1, the control unit 14 determines that the sensor data detected by the terminal device 1 should be transmitted to another terminal device Do. On the other hand, when the rank Rk detected from the Hello packet is equal to or less than the rank Rk of the terminal device 1, the control unit 14 determines that the sensor data detected by the terminal device 1 should not be transmitted to another terminal device.

  When the control unit 14 determines that the sensor data detected by the terminal device 1 should be transmitted to another terminal device, data in which the address of the terminal device 1 and the sensor data, the position information, and the time information are associated with each other Are generated, and the packet PKT_1 including the generated data and the address of the destination terminal device is generated, and the generated packet PKT_1 is output to the communication unit 13.

  The control unit 14 determines whether or not sensor data should be transmitted to the server 60 by a method described later, and when it is determined that the sensor data should be transmitted to the server 60, the sensor data detected by the terminal device 1 and And / or aggregate sensor data received from another terminal device by a method described later. Then, the control unit 14 generates a packet PKT_2 including the aggregated sensor data, and outputs the generated packet PKT_2 to the communication unit 13.

  The sensor 15 detects sensor data in accordance with control from the control unit 14, and outputs the detected sensor data to the control unit 14.

  The GPS 16 detects the position of the terminal device 1 according to the control from the control unit 14, and outputs position information indicating the detected position to the control unit 14.

  The storage unit 17 stores sensor data, position information, and time information in association with one another.

  Each of the terminal devices 2 to 10 shown in FIG. 1 also has the same configuration as the terminal device 1 shown in FIG.

  FIG. 3 is a schematic view of the server 60 shown in FIG. Referring to FIG. 3, server 60 includes a communication unit 61, a control unit 62, and a storage unit 63.

  The communication unit 61 detects sensor data and / or aggregated sensor data (aggregated) detected by the terminal devices 1 to 10 via the wireless base station (at least one of the wireless base stations 20, 30, 40) and the network 50. Sensor data) and outputs the received sensor data and / or aggregated sensor data to the control unit 62.

  The control unit 62 receives sensor data and / or aggregated sensor data from the communication unit 61, and stores the received sensor data and / or aggregated sensor data in the storage unit 63.

  The storage unit 63 stores sensor data and / or aggregated sensor data received from the control unit 62.

FIG. 4 is a conceptual view showing a storage format of sensor data. Referring to FIG. 4, sensor data name _{N_r} i (i is a positive integer), the time information time _(r i), the position information pos _{(r i)} and sensor data _{r i} are associated with each other.

The time information time (r _i ) is represented by the format YYYY / MM / DD / HH / SS. YYYY represents a year, MM represents a month, DD represents a day, HH represents a hour, and SS represents a minute.

The position information pos _{(r i)} is represented by longitude and latitude.

  The format of the sensor data may be anything. For example, the sensor data may be single data such as temperature, or may be tabular data such as signal strength for each frequency band.

FIG. 5 is a conceptual view of a cell. Referring to FIG. 5, the entire space to be detected sensor data (e.g., Japanese entire area) was divided in a grid pattern, a plurality of cells _{c 1, c 2, ···,} c L (L is , And an integer of 2 or more).

Each of the plurality of cells c ₁ , c ₂ ,..., C _L is, for example, a rectangle. The position of the center of gravity of each cell c ₁ , c ₂ ,..., C _L is referred to as the “representative position” of that cell.

FIG. 6 is a conceptual view of time slots. Referring to FIG. 6, time slots t ₀ , t ₁ ,... In which time is divided by a constant interval T _par are defined. The fixed interval T _par is, for example, 100 seconds or 5 minutes. The time at the midpoint of each time slot t ₀ , t ₁ ,... Is referred to as the “representative time” of that time slot.

In the embodiment of the present invention, a pair (c _i , t _j ) of a cell c _i and a certain time slot t _j (j is a positive integer) is a “space-time block” (or simply “block”) Say.

Then, when sensor data _{r k} is the pos _{(r k)} ∈ C _i to the cell _{c i,} and a time _{(r k)} ∈t _j with respect to the time slot _{t j,} block _{(c i} , T _j ) is called “the block to which r _k belongs” and is written as blk (r _k ). That is, when the position information pos sensor data _{r k (r k)} is included in the cell _{c i,} and the sensor data _{r k} of time information time _{(r k)} is included in time slot _{t j,} block _{(c i} , T _j ) is called “the block blk (r _k ) to which r _k belongs”.

[Reliability of sensor data]
The reliability of sensor data will be described. The sensor data _{r i,} a function that gives the confidence in the block _{b j} is referred to as a "reliability function", denoted rel _(r i, _{b j)} and.

FIG. 7 is a diagram for explaining the reliability function of sensor data. Referring to FIG. 7, each cube represents a block. The reliability function has the largest value in the block blk (r _k ) to which the sensor data r _k belongs, and approaches “0” for blocks farther from the block blk (r _k ). And the reliability determined by the reliability function consists of a real value of 0 or more and 1 or less.

  In FIG. 7, darker blocks represent higher reliability, and lighter blocks represent lower reliability.

In FIG. 7, each block is defined by a cell c _i and a time slot t _j (ie, defined by (c _i , t _j )), so the blocks arranged in the xy plane are cells c _i is the different blocks, blocks that are arranged in the time direction, the time slot t _j are different block.

Therefore, for blocks blk (r _i ) having the same cell c _i , blocks (c _i , t _{j -1} ), (c _i , t _j ), (c _i , t _{j + 1} ) having different time slots t _j , ... are defined.

FIG. 8 is a diagram showing an example of the reliability function. Referring to FIG. 8, the reliability function rel _(r i, _{b j),} when the d = 0, "1" becomes a value that linearly decreases as d increases. Then, the reliability function rel _(r i, _{b j),} when the d ≧ c, becomes "0". Here, c is a parameter.

Thus, the reliability function rel _(r i, _{b j),} in the range of d is 0 ≦ d <c, d is the value linearly decreases as the large and d is equal to or higher than c, the value It becomes "0".

Then, in the embodiment of the present invention, the reliability function rel ^space (r _i , b _j ) for the ^space and the reliability function rel ^time (r _i , b _j ) for the time are defined. In the embodiments of the invention, said reliability function _{^{rel space (r i, b j}} ) reliability determined by the "position confidence", the reliability function _{^{rel time (r i, b j}} ) The reliability determined by is called "time reliability".

Reliability function ^{_{rel space (r i, b j}} ) is expressed by the following equation.

In equation (1), c ₁ is a parameter, and d ₁ is a position pos (r _i ) of sensor data r _i and a representative of cell c _i of block b _j (= (c _i , t _j )) Represents the Euclidean distance to the position.

Reliability function ^{_{rel space (r i, b j}} ) , when the Euclidean distance _d 1 = 0, the value is "1", according to a longer Euclid distance _{d 1,} the value is linearly reduced. Then, the reliability function ^{_{rel space (r i, b j}} ) , when the Euclidean distance _{d 1} is _{c 1} or more, to "0".

It is the Euclidean distance _d 1 = 0 has a position sensor data _{r i} is detected, the representative position of the blocks _{b j} to sensor data _{r i} belongs indicates that equal, the reliability function ^{rel space} _{(r i} , B _j ) have the largest value (ie, the value is "1").

Further, the reliability function ^{_{rel time (r i, b j}} ) is expressed by the following equation.

In the formula (2), _{c 2} is a parameter, _{d 2} is the time of the time at which sensor data _{r i} is detected, the sensor data _{r i} belongs blocks _{b j (= (c i,} t j)) It represents the absolute value of the difference from the representative time of the slot t _j .

Reliability function ^{_{rel time (r i, b j}} ) , when the absolute value _d 2 = 0, "1", and the the absolute value _{d 2} is increased, the value is linearly reduced. Then, the reliability function ^{_{rel space (r i, b j}} ) , when the absolute value _{d 2} is _{c 2} or more, becomes "0".

It is an absolute value _d 2 = 0, the time the sensor data _{r i} is detected, the representative time of the time slot _{t j} of sensor data _{r i} belongs blocks _{b j (= (c i,} t j)) Since is equal, the reliability function rel ^time (r _i , b _j ) has the largest value (ie, the value is “1”).

Then, the reliability function rel _(r i, _{b j)} is expressed by the following equation.

  In equation (3), α is a weighting coefficient and is a real number satisfying 0 ≦ α ≦ 1.

Thus, the reliability function rel _(r i, _{b j)} is the reliability function ^{_{rel space (r i, b j}} ) and, expressed confidence function ^{_{rel time (r i, b j}} ) by the weighted sum of Ru.

  As a result, when weighting the reliability of space more than the reliability of time, setting α to a value larger than 0.5 and weighting the reliability of time more than the reliability of space Sets α to a value smaller than 0.5, and sets α to 0.5 when equally weighting the space reliability and the time reliability.

The parameter _c 1, _{c 2} may vary depending on the type of sensor data _{r i.}

In the above, the reliability function ^{_{rel space (r i, b j}} ) , the value according to the Euclidean distance _{d 1} is larger linearly decreases, the reliability function ^{_{rel time (r i, b j}} ) is Although it has been described that the value linearly decreases as the absolute value d ₂ increases, the embodiment of the present invention is not limited to this, and the reliability function rel ^space (r _i , b _j ) is the Euclidean distance d _as long as ₁ the value according to increases becomes smaller, may be any function, the reliability function ^{_{rel time (r i, b j}} ) , the value becomes smaller as the absolute value _{d 2} is greater As long as it is a thing, it may be any function.

FIG. 9 is a diagram for describing the effective range of sensor data in detail. Referring to FIG. 9, (either the terminal apparatus 10) terminal device detects sensor data r _i in cell c ₀ by itself exists, other than the cell (cell c ₀ present in the circle CIR In cell c), let r _i be assumed to give an estimate of the value of the sensor data in each cell (cell other than cell c ₀ ) with a certain degree of confidence.

Then, when the position and time of sensor data _{r i} detected in cell _{c 0} is represented by a respective position information pos _{(r i)} and time information time _{(r i),} other than the cell _{c 0} in a circle CIR cell It is estimated that the position and time of the sensor data r _i estimated in step are also represented by position information pos (r _i ) and time information time (r _i ), respectively. The area of the circle CIR is an area whose reliability is greater than "0". Therefore, the circle CIR is a circle whose radius is c ₁ described above.

Although FIG. 9 shows cells in the xy plane, since the cells also extend in the time direction, in fact, each cell in a sphere whose range of reliability is larger than “0” The sensor data r _{i at} is a candidate for uploading to the server 60.

Figure 10 is a diagram showing a block of sensor data r _i exists. FIG. 10 shows a block in which sensor data r _{0 to} r ₅ detected in the same time slot exist in a certain terminal device.

Referring to FIG. 10, sensor data _r 0 ~r _5, respectively, belong to the block _{blk (r 0) ~blk (r} 5).

11 and 12 show the reliability of the block to which the sensor data belongs. Note that FIG. 11A shows a diagram for calculating the reliability of the sensor data r ₀ belonging to the block blk (r ₀ ) shown in FIG. 10, and FIG. FIG. 11C is a diagram for calculating the reliability of the sensor data r ₂ belonging to the block blk (r ₂ ), and FIG. 11C shows the reliance on the sensor data r ₄ belonging to the block blk (r ₄ ) shown in FIG. Fig. 6 shows a diagram for calculating the degree. Then, in FIG. 11, for the sake of simplicity, the reliability of the block adjacent in the time direction is regarded as "0".

  For the sake of simplicity, it is assumed that the reliability calculation is performed as follows.

  (1) The reliability of the block to which the sensor data belongs is set to "1".

  (2) The reliability of a block in which cells are adjacent vertically and horizontally around the block to which sensor data belongs is set to "0.5".

  (3) The reliability of blocks other than the above is set to "0".

As a result, the calculation result of the reliability of the sensor data r ₀ belonging to the block blk (r ₀ ) is as shown in FIG. Further, the calculation result of the reliability regarding the sensor data r ₂ belonging to the block blk (r ₂ ) is as shown in (b) of FIG. Furthermore, the calculation result of the reliability of the sensor data r ₄ belonging to the block blk (r ₄ ) is as shown in (c) of FIG.

(A) of FIG. 12 shows a diagram for calculating a reliability related to sensor data _{r 3} belonging to the block blk _{(r 3)} shown in FIG. 10, (b) in FIG. 12, block blk shown in FIG. 10 FIG. 12 shows a diagram for calculating the reliability of sensor data r ₁ belonging to (r ₁ ), and FIG. 12C shows the reliability of sensor data r ₅ belonging to block blk (r ₅ ) shown in FIG. The figure for calculating is shown.

When calculating the reliability according to the above (1) to (3), the calculation result of the reliability relating to sensor data _{r 3} belonging to the block blk _{(r 3)} is as shown in FIG. 12 (a). The calculation result of the reliability of the sensor data r ₁ belonging to the block blk (r ₁ ) is as shown in (b) of FIG. Further, the calculation result of the reliability relating to sensor data _{r 5} belonging to the block blk _{(r 5)} is as shown in FIG. 12 (c).

FIG. 13 is a diagram showing a tally result obtained by tallying the calculation result of the reliability. Referring to FIG. 13, the reliability of sensor data r ₀ belonging to block blk (r ₀ ) is the block blk shown in (a) to (c) of FIG. 11 and (a) to (c) of FIG. The sum of the reliability values described in r ₀ ) yields 1 + 0.5 + 0.5 + 0 + 0 + 0 = 2.0.

  Similarly, the sum of the reliability values of sensor data belonging to all blocks is as shown in FIG.

Here, the aggregation processing candidate block set is B, the aggregation target sensor data set of block b _j is D (b _j ), the reliability of block b _j is R (b _j ), and the threshold value of reliability is Let R _thresh and let U _max be the maximum upload data number.

The aggregation process candidate block set B is a set of blocks to be candidates for the aggregation process. The aggregation target sensor data set D (b _j ) is a set of sensor data for performing the aggregation process on the block b _j . The reliability R (b _j ) is a numerical value for determining whether or not the sensor data after aggregation of the block b _j is to be uploaded to the server 60. Threshold _{R thresh} the reliability of the block _{b j} R _{(b j)} is equal to the threshold value _{R thresh} above, blocks _{b j} sensor data after aggregation to determine be uploaded to the server 60 It is a reference value. Maximum upload data number U _max, when each terminal 10 uploads the sensor data r _i to the server 60, a sensor number data which can not be exceeded.

As shown in FIG. 13, the total value of the reliability of the sensor data _{r i} belonging to each block (i.e., the reliability of the block R _(b j)) when obtaining the threshold _{R thresh} more reliability R (b sensor data r _i after aggregation block having a _j) determines to upload to the server 60.

_Assuming that the threshold value R _thresh is, for example, 2.0, in the case shown in FIG. 13, the sensor after aggregation of the blocks blk (r ₀ ), blk (r ₂ ), blk (r ₃ ), blk (r ₄ ) It is decided to upload data to the server 60.

The reliability R (blk (r ₀ )) (= 2.0) of the block blk (r ₀ ) is the reliability (= 1) based on the sensor data r ₀ and the reliability (= ₀ ) based on the sensor data r ₂ .5) and the reliability (= 0.5) based on the sensor data r ₄ , the aggregation target sensor data set D (blk (r ₀ )) is D (blk (r ₀ )) = {R ₀ , r ₂ , r ₄ }.

Also, the reliability R (blk (r ₂ )) (= 2.0) of the block blk (r ₂ ) is the reliability (= 1) based on the sensor data r ₂ and the reliability (based on the sensor data r ₀ ) = 0.5), (since the sum of the = 0.5), the aggregation target sensor data set D (blk _(r 2) reliability based on sensor data _{r 3)} is, D (blk _{(r 2} )) = a _{{r 0, r 2, r} 3}.

Furthermore, the reliability R (blk (r ₃ )) (= 2.5) of the block blk (r ₃ ) is the reliability (= 1) based on the sensor data r ₃ and the reliability (based on the sensor data r ₂ ) = 0.5), the reliability based on the sensor data _{r 4} and (= 0.5) are the sum of the confidence level based on the sensor data _{r 1} (= 0.5), the aggregation target sensor data set D _{(blk (r} 3)) becomes _{D (blk (r 3))} = {r 1, r 2, r 3, r 4}.

Furthermore, the reliability R (blk (r ₄ )) (= 2.5) of the block blk (r ₄ ) is the reliability (= 1) based on the sensor data r ₄ and the reliability (based on the sensor data r ₀ ) = 0.5), the reliability based on the sensor data _{r 3} and (= 0.5) are the sum of the confidence level based on the sensor data _{r 5} (= 0.5), the aggregation target sensor data set D (blk (r ₄ )) becomes D (blk (r ₃ )) = {r ₀ , r ₃ , r ₄ , r ₅ }.

  Describe aggregation of sensor data. There are two methods of aggregation processing for aggregating sensor data.

(Method 1)
Method 1, reliability is equal to the threshold _{R thresh} more, always, be used in the case that you want to collect the sensor data _{r i.}

(Method 2)
Scheme 2, want reliability collects the highest possible sensor data r _i, the number of sensor data r _i being uploaded to the server 60 is used when would like kept below the maximum upload data number U _max.

  Then, the operator of the system decides which of the methods 1 and 2 to use.

Figure 14 is a diagram showing an example of a grouping method sensor data r _i. Referring to FIG. 14, in the case of aggregating _two sensor data r ₁ and r ₂ by taking the maximum value, the aggregated sensor data after aggregation are time slot t _j , cell c _j and 33.1. Consists of a value.

Thus, the two sensor data _r 1, _{r 2} is aggregated into a single sensor data.

The method for aggregating sensor data r _i is not limited to taking the maximum value, taking the minimum value, taking the average value, and may be that like taking the median value.

As described above, aggregation target sensor data set D (blk (r ₀ )) = {r ₀ , r ₂ , r ₄ }, aggregation target sensor data set D (blk (r ₂ )) = {r ₀ , r ₂ , R ₃ }, aggregation target sensor data set D (blk (r ₃ )) = {r ₁ , r ₂ , r ₃ , r ₄ } and aggregation target sensor data set D (blk (r ₄ )) = {r ₀ , R ₃ , r ₄ , r ₅ }, the aggregation target sensor data set D (blk (r ₀ )), D (blk (r ₂ )), D (blk (r ₃ )), D (blk ( a plurality of sensor data r _i included in each of r _4)), is aggregated by aggregation method described above. Then, the aggregated sensor data r _i aggregated is uploaded to the server 60.

Each of the terminal devices 1 to 10 obtains the reliability R (b _j ) of the block b _j based on the reliability of each sensor data r _i by the above-described method, and the reliability R (threshold value _thresh or more) b _j) to aggregate sensor data set D _{(b j)} of the block having the uploading to the server 60.

In the above, the reliability R (b _j ) of the block b _j is obtained based on the reliability of the sensor data r _i detected in different cells c _i of the same time slot t _j , and the threshold R _thresh or more is obtained. In the above description, the sensor data set D (b _j ) of blocks having the reliability R (b _j ) of 1 is aggregated and uploaded to the server 60. However, in practice, detection is performed in different cells and / or different time slots. The reliability R (b _j ) of the block b _j is calculated based on the reliability of each sensor data r _i , and if the calculated reliability R (b _j ) is equal to or higher than the threshold R _thresh , the aggregation target sensor aggregates by the method described above a plurality of sensor data included in the data set D, up sensor data r _i was the aggregate to the server 60 To load.

Although the reliability of the block b _j has been described above as being determined according to the above (1) to (3), it is actually determined by the equations (1) to (3). In this case, even between blocks adjacent in a diagonal direction, it may determine the reliability by on the basis of the sensor data r _i Equation (1) to (3).

In the above, if the sensor data _{r i} the reliability R _{(b j)} is included in the aggregation target sensor data set D of blocks _{b j} is the threshold value _{R thresh} or _{(b j)} is plural, terminals each device 10 has been described to be uploaded to the server 60 by aggregating a plurality of sensor data _{r i,} aggregation of the reliability R _{(b j)} is the threshold _{R thresh} more blocks _{b j} If sensor data _{r i} included in the target sensor data set D _{(b j)} is one, each of the terminal device 10 is uploaded to the server 60 without aggregate sensor data _{r i.}

[Terminal communication]
FIG. 15 is a diagram showing the type of inter-terminal communication. In the embodiment of the present invention, two terminal devices mutually detect the address of the other party, and the two terminal devices mutually transmit and receive their own sensor data to the other party's terminal device using the short distance wireless communication system. This is called "inter-terminal communication".

  Referring to (a) of FIG. 15, the terminal devices p and q directly perform wireless communication with each other to detect the other terminal device. Then, the terminal devices p and q directly transmit and receive sensor data to each other.

  Referring to (b) of FIG. 15, the terminal devices p and q mutually detect the other terminal device via the wireless base station AP. Then, the terminal devices p and q directly transmit and receive sensor data mutually without passing through the radio base station AP.

  Referring to (c) of FIG. 15, the terminal devices p and q mutually detect the other terminal device via the wireless base station AP. Then, the terminal devices p and q mutually transmit and receive sensor data via the wireless base station AP. That is, the terminal devices p and q mutually detect the other terminal device and mutually transmit and receive sensor data via the radio base station AP.

  Thus, the "terminal-to-terminal communication" in the embodiment of the present invention includes the three systems shown in FIG.

Assign rank
Next, the method of assigning the rank Rk will be described.

  The physical address (for example, the MAC address) of the wireless interface of the terminal device is converted into an integer value to obtain a rank Rk. For example, “12: 34: 56: 78: 9 a: bc” is converted to “20015998343868”, and “20015998343868” is assigned to the terminal apparatus as a rank Rk.

  The allocation method of rank Rk may be other than this allocation method, and in general, any allocation as long as ranks Rk allocated to terminals 1 to 10 can be mutually identified. It may be a method.

  Note that the rank Rk does not necessarily have to be a numerical value, and conceptually, it may be an element of the “half-order set”. The "semi-ordered set" refers to a set in which two elements belonging to the set have a fixed order and one having an unordered order.

[Sensing timing of sensor data]
The timing of sensing sensor data is, for example, a predetermined cycle (for example, once every 10 minutes, once an hour, once a day, etc.), and is determined according to the type of sensor data. Timing etc. are assumed.

FIG. 16 is a conceptual diagram of communication between terminals. Referring to FIG. 16, terminal device p holds rank Rk = 2. Then, the terminal apparatus p detects sensor data _{r i} in a given cell _{c i} and a time slot _{t j.} Also, the terminal device q holds the rank Rk = 3. The terminal device q detects sensor data _{r i + 1} in a cell _{c i + 1} and a time slot _{t j + 1.}

  Thereafter, the terminal devices p and q move into the area REG1, and receive the Hello packet from the other terminal device. Then, the terminal device p detects the address Add_q of the terminal device q and the rank Rk = 3 from the Hello packet received from the terminal device q. The terminal device q also detects the address Add_p of the terminal device p and the rank Rk = 2 from the Hello packet received from the terminal device p.

Thereafter, the terminal apparatus p transmits sensor data r _i itself are detected to the terminal device q, terminal q receives the sensor data r _i. Also, the terminal device q transmits the sensor data ri _{+ 1} detected by itself to the terminal device p, and the terminal device p receives the sensor data ri _{+ 1} .

By this, each of the terminal devices p and q holds the sensor data r _i and r _{i + 1} . Then, the terminal device p obtains the reliability R (b _j ) in each block b _j from the sensor data r _i and the sensor data r _{i +1} .

Then, the terminal device p determines whether the reliability R (b _j ) in each block b _j is _{equal to} or higher than the threshold R _thresh , and the reliability R (b _j ) is _{equal to} or higher than the threshold R _thresh . when it is determined that the sensor data r _i and the sensor data r _{i + 1} aggregates by the method described above, to upload sensor data that aggregate to the server 60.

Incidentally, when the reliability R _{(b j)} is determined to be smaller than the threshold value _{R thresh,} terminal p uploads sensor data aggregated sensor data _{r i} and the sensor data _{r i + 1} to the server 60 Stop that.

Terminal q may, in the same manner as the terminal device p, uploaded to the server 60 to aggregate sensor data r _i and the sensor data r _{i + 1,} or sensor data r _i, r i + ₁ sensor data aggregated to the server 60 Stop uploading.

A terminal p is calculated reliability R _{(b j),} if both the reliability R of the terminal device q is calculated _{(b j)} is the threshold value _{R thresh} above, sensor data _{r i, r} i _{+ 1} is , terminal p, but are aggregated by both q is uploaded to the server 60, the terminal apparatus p is determined reliability R (b _j), the terminal device q the reliability R (b _j) and the obtained If only one of them is equal to or greater than the threshold value R _thresh , the sensor data r _i and r _{i + 1} are uploaded to the server 60 by only _one of the terminal devices p and q. Therefore, the load given to the network 50 can be reduced.

Terminal p, q for holding the sensor data _{r i,} the _{r i + 1,} the sensor data _r i by the following methods _may upload _{r i + 1} to the server 60.

That is, among the terminal devices p and q, the terminal device (one of the terminal devices p and q) having the highest rank Rk uploads the sensor data r _i and r _{i + 1} to the server 60.

In this case, the terminal device p, since rank Rk = 3 received from the terminal device q is higher than its own rank Rk = 2, the sensor data r _i itself are detected when encountering the terminal device q to the terminal device q send and delete the sensor data r _i by itself to hold, to stop the upload to the server 60. On the other hand, since the terminal device q has its own rank Rk = 3 higher than the rank Rk = 2 received from the terminal device p, it transmits the sensor data ri _{+ 1} detected by the terminal device p to the terminal device p at the time of encounter with the terminal device p. it suppresses the, then uploaded to the sensor data r _i and sensor data r _{i + 1} and the server 60 aggregates the received from the terminal apparatus p. This can reduce the load applied to the network 50.

The number of terminal devices performing inter-terminal communication in the region REG1 is not limited to two, and may be three or more. In this case, three or more terminal devices, self send and receive each other sensor data r _i detected, obtains the reliability R (b _j) of each block from the transmitted and received sensor data, the reliability R (b _j The sensor data r _i is aggregated and uploaded to the server 60 for a block whose) is greater than or _equal to the threshold R _thresh . Of the three or more terminal devices may be uploaded only terminal device having the highest rank Rk is to aggregate sensor data r _i to the server 60.

  FIG. 17 is a flowchart for explaining the operations of the terminal devices p and q and the server 60. The terminal device p is any of the terminal devices 1 to 10, and the terminal device q is a terminal device different from the terminal device p among the terminal devices 1 to 10.

Referring to FIG. 17, sensor 15 of terminal device p periodically senses sensor data r _p (steps S1 to S3), and outputs the sensed sensor data r _p to control unit 14.

When receiving the sensor data r _p from the sensor 15, the control unit 14 detects the time when the sensor data r _p is received based on the timer, and generates time information time (r _p ) indicating the detected time. Do. Further, the control unit 14 receives, from the GPS 16, the position information pos (r _p ) when the sensor data r _p is received. Then, the control unit 14 stores the sensor data r _p , the time information time (r _p ), and the position information pos (r _p ) in the storage unit 17 in association with each other.

Meanwhile, the sensor 15 of the terminal device q also periodically senses the sensor data r _q (steps S4 to S6), and outputs the sensed sensor data r _q to the control unit 14. Then, the control unit 14 of the terminal device _{q associates} the sensor data r _q , time information time (r _q ) and position information pos (r _q ) with each other in the same manner as the control unit 14 of the terminal device p It is stored in the unit 17.

  Then, the terminal devices p and q mutually detect the other terminal and perform inter-terminal communication (steps S7 and S8).

Thereafter, the sensor 15 of the terminal device p senses the sensor data r _p (step S9), and outputs the sensed sensor data r _p to the control unit 14. The control unit 14 of the terminal device p stores the sensor data r _p , the time information time (r _p ) and the position information pos (r _p ) in the storage unit 17 in association with one another by the above-described method.

Then, the control unit 14 of the terminal device p aggregates the sensor data r _p stored in the storage unit 17 and outputs the collected sensor data r _p to the communication unit 13. The communication unit 13 collects the collected sensor data The r _p is uploaded to the server 60 via the antenna 12 (step S10).

On the other hand, after step S8, the sensor 15 of the terminal device q senses the sensor data r _q (step S11), and outputs the sensed sensor data r _q to the control unit 14. The control unit 14 of the terminal device q stores the sensor data r _q , the time information time (r _q ) and the position information pos (r _q ) in the storage unit 17 in association with one another by the above-described method.

Then, the control unit 14 of the terminal device q aggregates the sensor data r _q stored in the storage unit 17 and outputs the collected sensor data r _q to the communication unit 13, and the communication unit 13 collects the collected sensor data r _q is uploaded to the server 60 via the antenna 12 (step S12).

The communication unit 61 of the server 60 (step S13) which receives the sensor data _{r q} from the terminal q, receives the sensor data _{r p} from the terminal device p (step S14). Then, the communication unit 61 of the server 60 outputs the received sensor data r _p and r _q to the control unit 62, and the control unit 62 stores the sensor data r _p and r _q received from the communication unit 61. Store in

After step S10, the sensor 15 of the terminal device p senses the sensor data r _p (step S15), and outputs the sensed sensor data r _p to the control unit 14. The control unit 14 of the terminal device p stores the sensor data r _p , the time information time (r _p ) and the position information pos (r _p ) in the storage unit 17 in association with one another by the above-described method.

In addition, after step S12, the sensor 15 of the terminal device q senses the sensor data r _q (step S16), and outputs the sensed sensor data r _q to the control unit 14. The control unit 14 of the terminal device q stores the sensor data r _q , the time information time (r _q ) and the position information pos (r _q ) in the storage unit 17 in association with one another by the above-described method.

  The terminal devices p and q and the server 60 repeatedly execute the operation described above.

  As a result, each of the terminal devices p and q aggregates the sensed sensor data and uploads it to the server 60 (that is, uploads a part of the sensed sensor data to the server 60), so the load given to the network 50 is achieved. It can be reduced.

FIG. 18 is a diagram showing a flowchart for explaining the sensor data aggregation process. Referring to FIG. 18, when the aggregation processing of sensor data _{r i} is started, the control unit 14 of the terminal device 10 performs the pre-process aggregation (step S21). Then, the control unit 14 of the terminal devices 1 to 10 performs aggregation processing (step S22). Thereafter, the control unit 14 of the terminal device 10 outputs the sensor data r _i that aggregates to the communication unit 13, the communication unit 13 stores the sensor data r _i received from the control unit 14 to the transmission buffer, antenna all sensor data _{r i} in the transmission buffer through the 12 to upload to the server 60 (step S23). This completes the aggregation process.

  FIG. 19 is a flowchart for explaining the detailed operation of step S21 shown in FIG.

  Referring to FIG. 19, when aggregation processing is started, control unit 14 of terminal devices 1 to 10 sets aggregation processing candidate block set B to “0” (step S211), and sets i = 0. (Step S212).

Then, the control unit 14 of the terminal devices 1 to 10 extracts all blocks b _j whose reliability function rel (r _i , b _j ) is larger than “0” with respect to the sensor data r _i (step S213). In this case, the control unit 14 of the terminal devices 1 to 10 extracts all of the blocks b _j included in the circle CIR shown in FIG. 9, and sets the total number of the extracted blocks b _j as Jmax.

Thereafter, the control unit 14 of the terminal devices 1 to 10 sets j = 0 (step S214), and determines whether the block b _j is included in the aggregation processing candidate block set B (step S215).

When it is determined in step S215 that the block b _j is not included in the aggregation processing candidate block set B, the control unit 14 of the terminal devices 1 to 10 sets the aggregation target sensor data set D (b _j ) to “0”. The reliability R (b _j ) of the block b _j is set to “0”, the union of the aggregation process candidate block set B and the block b _j is calculated, and the calculated union is the aggregation process candidate block Set B (step S216).

When it is determined in step S215 that the block b _j is included in the aggregation processing candidate block set B, or after step S216, the control unit 14 of the terminal device 1 to 10 collects the aggregation target sensor data set D (b _j ) And the sensor data r _i are calculated, and the calculated sum set is set as the aggregation target sensor data set D (b _j ), and the reliability R (b _j ) of the block b _j and the reliability function rel ( The sum of r _i and b _j ) is calculated, and the calculated sum is set as the reliability R (b _j ) of the block b _j (step S217).

Thereafter, the control unit 14 of the terminal devices 1 to 10 determines whether j = Jmax (step S218). Note that Jmax is the total number of blocks b _j extracted in step S213.

  If it is determined in step S218 that j = Jmax is not satisfied, the control unit 14 of each of the terminal devices 1 to 10 sets j = j + 1 (step S219). After that, the series of operations proceeds to step S215, and steps S215 to S219 are repeatedly executed until it is determined in step S218 that j = Jmax.

  Then, if it is determined in step S218 that j = Jmax, the control unit 14 of each of the terminal devices 1 to 10 determines whether i = Imax (step S220). Note that Imax is the total number of sensor data to be consolidated.

  When it is determined in step S220 that i is not i = Imax, the control unit 14 of each of the terminal devices 1 to 10 sets i = i + 1 (step S221). Thereafter, the series of operations proceeds to step S213, and steps S213 to S221 are repeatedly executed until it is determined in step S220 that i = Imax.

  When it is determined in step S220 that i = Imax, the series of operations proceeds to step S22 shown in FIG.

Setting D (b _j ) = 0, R (b _j ) = 0 and B = B∪ {b _j } in step S216 is a flowchart for performing pre-processing of aggregation in the flowchart shown in FIG. Because it is to initialize.

Further, in step _{S217, D (b j) =} D (b j) to set the ∪ _{{r i}} is for the purpose of the object of aggregate sensor data _{r i, R (b j)} = R ( The reason that b _j ) + rel (r _i , b _j ) is set is to update the reliability R (b _j ) by subjecting the sensor data r _i to aggregation. Then, by repeatedly executing step S217, as described in FIG. 10 to FIG. 12, the reliability R (b _j ) of each block b _j is determined by the reliability function rel (r _i , b _j ) The sum of Jmax reliabilities in the block b _j is calculated, and the aggregation target sensor data set D (b _j ) has the reliability in the block b _j that is larger than “0” among the Jmax reliabilities. consists of all of the sensor data _{r i.}

Therefore, for all the sensor data r _i, by executing the flowchart shown in FIG. 19, the aggregation process candidate block set B necessary for aggregation processing, aggregation target sensor data set D (b _j), and the reliability R (b _j ) Is determined.

  FIG. 20 is a flowchart for explaining the detailed operation of step S22 shown in FIG. The flowchart shown in FIG. 20 is a flowchart for explaining the detailed operation of the aggregation process (step S22 in FIG. 18) in the above-described method 1.

  Referring to FIG. 20, in step S21 of FIG. 18, when the aggregation pre-processing ends, the control unit 14 of the terminal devices 1 to 10 sets j = 0 (step S222).

Then, the control unit 14 of the terminal devices 1 to 10 determines whether the reliability R (b _j ) of the block b _j is _{equal to} or more than the threshold R _thresh (step S223).

When it is determined in step S223 that the reliability R (b _j ) of the block b _j is _{equal to} or greater than the threshold R _thresh , the control unit 14 of the terminal device 1 to 10 collects the aggregation target sensor data set D (b _j ) to be for all sensor data r _i belonging to execute the aggregate operation (step S224).

Then, the control unit 14 of the terminal device 10 outputs the sensor data _{r i} that aggregates to the communication unit 13, the communication unit 13 adds the sensor data _{r i} which is integrated into the transmission buffer (step S225).

When it is determined in step S223 that the reliability R (b _j ) of the block b _j is not greater than or _equal to the threshold R _thresh , or after step S225, the control unit 14 of the terminal devices 1 to 10 sets j = Jmax. It is determined whether there is any (step S226).

  When it is determined in step S226 that j = Jmax is not satisfied, the control unit 14 of each of the terminal devices 1 to 10 sets j = j + 1 (step S227). Thereafter, the series of operations proceeds to step S223, and steps S223 to S227 are repeatedly executed until it is determined in step S226 that j = Jmax.

  When it is determined in step S226 that j = Jmax, the series of operations proceeds to step S23 in FIG.

By executing the flowchart shown in FIG. 20, sensor data _{r i} belonging to the block _{b j} with a threshold _{R thresh} more reliability R _{(b j)} is added to the transmission buffer are aggregated. After that, step S23 of FIG. 18 is executed, all the sensor data r _i in the transmission buffer is uploaded to the server 60.

  FIG. 21 is a flowchart illustrating another detailed operation of step S22 shown in FIG. The flowchart shown in FIG. 21 is a flowchart for explaining the detailed operation of the aggregation process (step S22 in FIG. 18) in the above-described method 2. The flowchart shown in FIG. 21 is obtained by replacing steps S222 and S223 of the flowchart shown in FIG. 20 with steps S228 and S229 and replacing steps S226 and S227 of the flowchart shown in FIG. 20 with step S230. This is the same as the flowchart shown in FIG.

Referring to FIG. 21, in step S21 of FIG. 18, when the aggregation pre-processing ends, the control unit 14 of the terminal devices 1 to 10 sets n = 0 (step S228). Here, n is a positive integer, is the number of sensor data r _i to be uploaded to the server 60.

After step S228, the control unit 14 of the terminal device 10, the number n of sensor data _{r i} to be uploaded to the server 60 determines whether greater than the maximum upload speed _{U max} (step S229).

In step S229, when the number n of sensor data _{r i} to be uploaded to the server 60 is not greater than the maximum upload speed _{U max,} the steps S224, S225 described above is sequentially executed.

Then, after step S225, the control unit 14 of the terminal devices 1 to 10 sets n = n + 1 (step S230). Thereafter, the series of operations proceeds to step S229, in step S229, until the number n of sensor data _{r i} to be uploaded to the server 60 is determined to be greater than the maximum upload speed _{U max,} step S229, S224, S225 , S230 is repeatedly executed.

Then, in step S229, the number n of sensor data _{r i} to be uploaded to the server 60 is determined to be greater than the maximum upload speed _{U max,} a series of operations proceeds to step S23 in FIG. 18.

Even if the number of sensor data r _i belonging to the aggregation target sensor data set D (b _j) is one, the flow chart shown in FIG. 20 or 21 is executed. In this case, since the aggregation operation includes taking the maximum value, taking the minimum value, taking the median value, and the like as described above, there is no problem in performing step S224.

  FIG. 22 is a diagram showing a flowchart for explaining the hello packet transmission operation.

  Referring to FIG. 22, when the transmission operation of the Hello packet is started, the control unit 14 of each of the terminal devices 1 to 10 receives the address of the terminal device (one of the terminal devices 1 to 10) on which the terminal device 1 is mounted. A Hello packet including the rank Rk is generated, and the generated Hello packet is output to the communication unit 13.

  Then, the communication unit 13 of the terminal devices 1 to 10 broadcasts the Hello packet received from the control unit 14 via the antenna 11 using the short distance wireless communication system (step S31).

  Thereafter, the control unit 14 of the terminal devices 1 to 10 stands by for a fixed time (step S32).

  Then, each of the terminal devices 1 to 10 repeatedly executes steps S31 and S32 to periodically broadcast a Hello packet.

  FIG. 23 is a diagram showing a flowchart for explaining the operation of the reception side terminal and the transmission side terminal of the Hello packet.

  Referring to FIG. 23, when a series of operations are started, communication unit 13 of the reception side terminal of the Hello packet receives the Hello packet via antenna 11 (step S41), and controls the received Hello packet. Output to unit 14.

  Then, the control unit 14 of the terminal on the receiving side of the Hello packet receives the Hello packet from the communication unit 13. Thereafter, the control unit 14 of the terminal on the receiving side of the Hello packet generates a Hello packet including the address of the terminal apparatus on which the self packet is mounted and the rank Rk, and outputs the generated Hello packet to the communication unit 13.

  The communication unit 13 of the terminal on the receiving side of the Hello packet receives the Hello packet from the control unit 14, and transmits the received Hello packet via the antenna 11. That is, the communication unit 13 of the terminal on the receiving side of the Hello packet transmits the information of the own terminal to the transmission source terminal (destination terminal) of the Hello packet (step S42).

  The communication unit 13 of the transmitting terminal of the Hello packet receives the information (= Hello packet) of the other terminal from the other terminal via the antenna 11 (step S43), and the received information (= Hello packet) of the other terminal is received. It outputs to the control unit 14.

  Thereafter, the control unit 14 of the transmission side terminal of the Hello packet generates a Hello packet including the address of the terminal apparatus on which the self packet is mounted and the rank Rk, and outputs the generated Hello packet to the communication unit 13.

  Then, the communication unit 13 of the transmission side terminal of the Hello packet receives the Hello packet from the control unit 14, and transmits the received Hello packet via the antenna 11. That is, the communication unit 13 of the transmission side terminal of the hello packet transmits the information (Hello packet) of the own terminal to the opposite terminal (step S44).

  The communication unit 13 of the terminal on the receiving side of the Hello packet receives the information (= Hello packet) of the other terminal from the other terminal via the antenna 11 (step S45), and the received information (= Hello packet) of the other terminal It outputs to the control unit 14.

Then, the control unit 14 of the reception side terminal of the Hello packet, and outputs sensor data _{r i} to the communication unit 13, the communication unit 13 executes transmission processing (step S46).

The communication unit 13 of the transmitting terminal of the Hello packet, via the antenna 11 receives the sensor data _{r i} from the partner terminal (step S47), and outputs sensor data _{r i} where the received to the control unit 14.

Thereafter, the control unit 14 of the transmitting terminal of the Hello packet, and outputs sensor data _{r i} to the communication unit 13, the communication unit 13 executes transmission processing (step S48).

The communication unit 13 of the receiving terminal of the Hello packet, via the antenna 11 receives the sensor data _{r i} from the partner terminal (step S49), and outputs sensor data _{r i} where the received to the control unit 14.

  After step S48, the operation of the transmitting terminal of the hello packet ends, and after step S49, the operation of the receiving terminal of the hello packet ends.

  FIG. 24 is a flowchart for explaining the detailed operation of step S46 of FIG.

  Referring to FIG. 24, after step S45 in FIG. 23, the control unit 14 of the terminal on the receiving side of the Hello packet sets i = 0 (step S461).

Then, the control unit 14 of the reception side terminal of the Hello packet, if the sensor data r _i is better partner terminal is held is determined to be appropriate, and outputs sensor data r _i to the communication unit 13. Then, the communication unit 13 of the receiving terminal of the Hello packet, receives the sensor data _{r i} from the control unit 14, adds the received sensor data _{r i} to the transmission buffer. That is, the reception side terminal of the Hello packet, if the sensor data r _i is better partner terminal is held is determined to be appropriate, to add a sensor data r _i to the transmit buffer (step S462).

  Then, the control unit 14 of the reception side terminal of the hello packet determines whether i = Imax (step S463).

  When it is determined in step S463 that i is not i = Imax, the control unit 14 of the receiving terminal of the Hello packet sets i = i + 1 (step S464). Thereafter, the series of operations proceeds to step S462, and steps S462 to S464 are repeatedly executed until it is determined in step S463 that i = Imax.

Then, in step S463, when it is determined that the i = Imax, the communication unit 13 of the receiving terminal of the Hello packet, transmits the sensor data _{r i} in the transmission buffer through the antenna 11 to the other terminal (step S465).

  Thereafter, the series of operations proceeds to step S47 in FIG.

  The operation of step S48 in FIG. 23 is also executed in accordance with the flowchart shown in FIG.

  FIG. 25 shows a flowchart for explaining the detailed operation of step S462 shown in FIG.

  Referring to FIG. 25, after step S461 in FIG. 24, the control unit 14 of the terminal on the Hello packet receiving side determines whether the rank Rk of the own terminal is smaller than the rank Rk of the other terminal (step S4621). ).

In step S4621, when the rank Rk of the terminal is determined to be less than the rank Rk of the counterpart terminal, the control unit 14 of the reception side terminal of the Hello packet, and outputs sensor data _{r i} to the communication unit 13, the communication unit 13 adds the sensor data _{r i} received from the control unit 14 to the transmit buffer (S4622).

On the other hand, in step S4621, when the rank Rk of the terminal is determined to not less than the rank Rk opponent terminal, the receiving terminal of the Hello packet, stops transmission to the other terminal of the sensor data r _i (step S4623).

  Then, after step S4622, the series of operations proceeds to step S463 of FIG. 24, and after step S4623, the series of operations proceeds to step S48 of FIG.

According to the flowchart shown in FIG. 25, when the rank Rk of the terminal is determined to be less than the rank Rk of the partner terminal, sensor data _{r i} is added to the transmit buffer (step S4621 "YES", the step S4622 (Refer to step S465 in FIG. 24).

Meanwhile, when the rank Rk of the terminal is determined to not less than the rank Rk opponent terminal, transmission to the partner terminal of sensor data r _i is stopped (see step S4623). This is due to the following reason. If it is determined that the rank Rk of the own terminal is not smaller than the rank Rk of the opposite terminal, the rank Rk of the own terminal is higher than the rank Rk of the opposite terminal, and the rank Rk of the own terminal is equal to the rank Rk of the opposite terminal. There is the same case. If rank Rk of the terminal is greater than the rank Rk opponent terminal, the host terminal so should upload sensor data r _i to the server 60, it transmits to the other terminal of the sensor data r _i is stopped. Also, if the rank Rk of the terminal is the same as the rank Rk partner terminal, both own terminal and the mating terminal, respectively, so should upload sensor data r _i which self holds the server 60, the sensor Transmission of the data r _{i to} the other terminal is stopped.

Thus, determination of whether the sensor data r _i is better partner terminal is held is appropriate is performed using the rank Rk assigned to each terminal device 10.

Note that determines whether the sensor data _{r i} is better partner terminal is held is appropriate is not limited to the rank Rk assigned to each terminal device 10, in Japanese Patent Application No. 2016-196933 by the present inventors As described, it may be determined that the terminal expected to be closer to the dwell point holds sensor data.

  The inter-terminal communication in steps S7 and S8 shown in FIG. 17 is executed according to the flowcharts shown in FIGS. Further, the aggregation of steps S10 and S12 shown in FIG. 17 and the uploading to the server 60 are executed according to the flowcharts shown in FIG. 18, FIG. 19 and FIG. 20 (or FIG. 21).

Then, when the sensor data detected by the own terminal and the sensor data received from the other terminal by inter-terminal communication are aggregated, the reliability of the sensor data detected by the own terminal in step S223 of FIG. From the reliability of the received sensor data, the sum R (b _j ) of the reliability in each block is determined, and it is determined whether the calculated sum R (b _j ) is _{equal to} or greater than the threshold R _thresh Ru.

When it is determined that the total sum R (b _j ) is _{equal to} or greater than the threshold value R _thresh , steps S224 and S225 are sequentially executed. On the other hand, when it is determined that the sum R (b _j ) is not greater than or _equal to the threshold R _thresh , steps S224 and S225 are not performed (that is, sensor data is not uploaded to the server 60).

  In the embodiment of the present invention, the operations of the terminal devices 1 to 10 may be realized by software.

  In this case, each of the terminal devices 1 to 10 includes a central processing unit (CPU), a read only memory (ROM), and a random access memory (RAM).

  The ROM of each of the terminal devices 1 to 10 corresponds to steps S1 to S3, S7, S9, S10 and S15 of the flowchart shown in FIG. 17 (steps S21 to S23 of the flowchart shown in FIG. 18 and steps S221 to S221 in the flowchart shown in FIG. Step S221, steps S222 to S227 of the flowchart shown in FIG. 20 (or steps S228, S229, S224, S225, S230 of the flowchart shown in FIG. 21), steps S31 and S32 of the flowchart shown in FIG. Steps S41, S42, S45, S46, S49 (or steps S43, S44, S47, S48 of the flowchart shown in FIG. 23, steps S461 to S465 of the flowchart shown in FIG. 24, and steps of the flowchart shown in FIG. Storing program Prog_A comprising a containing up S4621~S4623).

  Further, the ROM of each of the terminal devices 1 to 10 corresponds to steps S4 to S6, S8, S11, S12 and S16 of the flowchart shown in FIG. 17 (steps S21 to S23 of the flowchart shown in FIG. Steps S222 to S227 of the flowchart shown in FIG. 20 (or steps S228, S229, S224, S225, S230 of the flowchart shown in FIG. 21), steps S31 and S32 of the flowchart shown in FIG. Steps S41, S42, S45, S46, S49 (or Steps S43, S44, S47, S48 of the flowchart shown in FIG. 23), Steps S461 to S465 of the flowchart shown in FIG. 24, and the flowchart shown in FIG. Storing program Prog_B comprising including) the steps S4621～S4623.

  The RAM temporarily stores intermediate results of the operation.

Then, CPU reads out and executes a program prog_a (or program PROG_B) from ROM, the method described above, to upload sensor data _{r i} to the server 60.

  Also, the program Prog_A (or the program Prog_B) may be distributed by being recorded on a recording medium such as a CD or a DVD.

When mounting the recording medium recording the program prog_a (or program PROG_B) to the personal computer, CPU, executes the recording medium by reading the program prog_a (or program PROG_B), by the method described above, the server 60 the sensor data _{r i} Upload to

  Therefore, the recording medium recording the program Prog_A (or the program Prog_B) is a computer (CPU) readable recording medium.

In the embodiments of the invention, the control unit 14 to determine the sensor data r _i to be uploaded to the server 60 by the method described above, among the sensor data r _i detected by the sensor 15, the reliability of the sensor data There constituting the "processing means" for performing determination processing for determining the sensor data to be transmitted sensor data r _i is greater than or equal to the threshold value to the server 60.

Further, in embodiments of the present invention, a communication unit 13 for transmitting the sensor data r _i to the server 60, the sensor data r _i determined by the control unit 14 transmits to the server 60 constitute the "transmission means" .

In the above, by dividing the detected spatial sensor data r _i in cell c _i, when uploading the divided cell c _i, and the sensor data r _i detected by the time slot t _j to the server 60 by the above-described method has been described, in the embodiment of the present invention is not limited thereto, without defining a cell c _i and the time slot t _j, the position information indicating the detected position of the sensor data r _i pos and (r _i) , holds the time information indicating time detecting the sensor data r _i time (r _i) in association with the sensor data r _i, of the sensor data r _i that its retention, sensor data to be uploaded to the server 60 determined by the above-described method, the position information pos (r _i) and time information to aggregate sensor data the determined along with the time _{(r i)} as long as you want to upload to the server 60.

  Therefore, the terminal device according to the embodiment of the present invention is a sensor that detects sensor data, and among the detected sensor data, sensor data that transmits sensor data whose sensor data reliability is equal to or higher than a threshold to the server And the transmission means for transmitting the determined sensor data to the server.

  If the terminal device includes the sensor, the processing means, and the transmission means, among the detected sensor data, the sensor data whose reliability is equal to or more than the threshold value is transmitted to the server to load the communication network. It is because it can reduce.

  Further, the wireless communication system according to the embodiment of the present invention may include the above-described terminal device and a server that receives sensor data from the terminal device and holds the received sensor data.

  If the wireless communication system includes the terminal device and the server, it is possible to reduce the communication load when the terminal device transmits sensor data to the server.

Furthermore, in the program according to the embodiment of the present invention, the processing means determines, as sensor data to be transmitted to the server, sensor data having a reliability of the sensor data equal to or higher than a threshold among sensor data detected by the sensor. A first step of performing determination processing;
The transmission means may be a program for causing the computer to execute the second step of transmitting a part of the sensor data determined in the first step to the server.

  If the program causes the computer to execute the first and second steps, among the detected sensor data, sensor data whose reliability is equal to or higher than the threshold value is transmitted to the server, and the load on the communication network can be reduced. It is.

  It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

  The present invention is applied to a terminal device, a wireless communication system including the same, a program to be executed by a computer, and a computer readable recording medium recording the program.

  1 to 10 terminal devices, 11, 12 antennas, 13, 61 communication units, 14, 62 control units, 15 sensors, 16 GPS 17, 63 storage units, 20, 30, 40 wireless base stations, 50 networks, 60 servers, 100 Wireless communication system.

Claims (14)

Sensors that detect sensor data,
Processing means for performing a determination process of determining sensor data having a reliability of the sensor data equal to or greater than a threshold among the detected sensor data as sensor data to be transmitted to the server;
And a transmitting unit configured to transmit the determined sensor data to the server. The processing unit aggregates a plurality of sensor data when there are a plurality of sensor data whose reliability of the sensor data is equal to or greater than a threshold value,
The terminal device according to claim 1, wherein the transmission unit transmits the aggregated sensor data to the server. When the terminal device on which the processing unit is mounted receives sensor data from another terminal device, the processing means may measure the reliability of the sensor data received from the other terminal device and the reliability of the sensor data detected by the sensor. Calculating a sum of the degree of freedom, and when the calculated sum is equal to or greater than a threshold, aggregating sensor data received from the other terminal device and sensor data detected by the sensor;
The terminal device according to claim 1, wherein the transmission unit transmits the aggregated sensor data to the server.   The terminal device according to claim 3, wherein the transmitting unit transmits the aggregated sensor data to the server when the rank of the terminal device on which the terminal device is mounted is higher than the rank of another terminal device. The sensor data is defined by position information indicating a detected position and time information indicating a detected time,
The processing means includes a weighted sum of a position reliability indicating the reliability of the position at which the sensor data is detected and a time reliability indicating the reliability of the time at which the sensor data is detected. The terminal device according to claim 1, wherein the determination process is performed using the reliability. The position reliability decreases as the distance between the position of the sensor data detected in the other terminal device and the position of the sensor data detected by the sensor increases, and the sensor detected in the other terminal device The higher the distance between the data position and the sensor data position detected by the sensor, the higher the
The time reliability becomes lower as the absolute value of the difference between the time of sensor data detected in the other terminal device and the time of sensor data detected by the sensor becomes larger, and detection is performed in the other terminal device The terminal device according to claim 5, wherein as the absolute value of the difference between the time of the detected sensor data and the time of the sensor data detected by the sensor decreases, it increases. The terminal device according to any one of claims 1 to 6, and
A wireless communication system, comprising: sensor data received from the terminal device; and a server holding the received sensor data. A first step of performing a determination process of determining, as sensor data to be transmitted to the server, sensor data having a reliability of the sensor data equal to or greater than a threshold among the sensor data detected by the sensor;
A program for causing a computer to execute a second step in which transmitting means transmits the sensor data determined in the first step to the server. In the first step, the processing means aggregates a plurality of sensor data when there are a plurality of sensor data whose reliability of the sensor data is equal to or greater than a threshold value,
The program for causing a computer to execute according to claim 8, wherein in the second step, the transmission means transmits the aggregated sensor data to the server. In the first step, when the terminal device on which the processing unit is mounted receives sensor data from another terminal device, the processing means uses reliability of sensor data received from the other terminal device, and the sensor A sum of reliability of detected sensor data is calculated, and when the calculated sum is equal to or greater than a threshold value, sensor data received from the other terminal device and sensor data detected by the sensor are aggregated And
The program for causing a computer to execute according to claim 8, wherein in the second step, the transmission means transmits the aggregated sensor data to the server.   11. The method according to claim 10, wherein, in the second step, the transmitting unit transmits the aggregated sensor data to the server when the rank of the terminal device on which the self terminal is mounted is higher than the rank of another terminal device. A program for causing a computer as described to execute. The sensor data is defined by position information indicating a detected position and time information indicating a detected time,
In the first step, the processing means includes a position reliability indicating a reliability of the position at which the sensor data is detected, and a time reliability indicating a reliability of the time at which the sensor data is detected. The program according to claim 8, wherein the determination process is performed using a weighted sum as the reliability of the sensor data. The position reliability decreases as the distance between the position of the sensor data detected in the other terminal device and the position of the sensor data detected by the sensor increases, and the sensor detected in the other terminal device The higher the distance between the data position and the sensor data position detected by the sensor, the higher the
The time reliability becomes lower as the absolute value of the difference between the time of sensor data detected in the other terminal device and the time of sensor data detected by the sensor becomes larger, and detection is performed in the other terminal device The program according to claim 12, wherein the absolute value of the difference between the detected sensor data time and the sensor data time detected by the sensor decreases.   A computer readable recording medium recording the program according to any one of claims 8 to 13.

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