JP2019075623A - Group communication system, terminal device, position information notification method, and program - Google Patents

Abstract

To provide a group communication system and the like that can appropriately disclose positional information while protecting privacy.SOLUTION: A secret area determination unit 442 determines a secret area to be kept secret and a secret level in its terminal on the basis of multiple pieces of positional information determined by a positioning unit 441. A disclosure positional information generation unit 443 generates disclosure positional information obtained by adjusting current positional information on the basis of a positional relationship between the current positional information determined by the positioning unit 441 and the secret area determined by the secret area determination unit 442 and the secret level. A transmission/reception unit 420 transmits the disclosure positional information generated by the disclosure positional information generation unit 443 to a management server and receives disclosure positional information on another user terminal 400 transmitted from the management server. A display unit 450 displays a map screen on which an image representing the other user terminal 400 is disposed on a map on the basis of the disclosure positional information received by the transmission/reception unit 420.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a group communication system, a terminal device, a position information notification method, and a program capable of appropriately disclosing position information while protecting privacy.

  Conventionally, SNS (Social Networking Service) using a smart phone etc. is used widely. In such SNSs, it is possible not only to send and receive messages, but also to share location information with each other.

  As a prior art of a system that shares location information, for example, Patent Literature 1 discloses a stroller rental that allows users to share location information of users (members) who are using a stroller by using SNS. The invention of the system is disclosed.

JP 2017-49777 A

In the stroller / rental system and the like of Patent Document 1 described above, when the location information is set to be notified, location information indicating the location is disclosed to other users no matter where the user is. Will be notified).
In addition, important places such as a home, a school, a work place, etc. are basically concealed areas to be concealed, and it is desirable not to disclose such positional information, especially between users who are not close.

  Therefore, when the user is at home or the like, it is necessary to manually change the setting so as not to notify the position information, which is extremely troublesome. A place such as a home may be registered in advance, and the setting may be automatically switched so as not to notify position information when the user approaches such a registered place.

However, even if the notification about the position information is automatically switched, if a place where the position information is not notified is specified, it may be predicted that the place is a home or the like. For example, if it has a function of storing position information and displaying a movement locus, the blank area in the movement locus (that is, the area from when the movement locus is once interrupted until the movement locus starts again) It will also be possible to identify. And if such a blank area is frequently checked in the same place, it will be easily predicted that the place is at home or the like.
That is, even if the location information is not notified only to the registered place such as the home, there is a problem that the home or the like may be predicted from the location information without the notification.

  The present invention was made in view of the above situation, and provides a group communication system, a terminal device, a position information notification method, and a program capable of appropriately disclosing position information while protecting privacy. To aim.

The group communication system according to the present invention is
A group communication system in which a plurality of terminal devices and a server device that manages group communication between the terminal devices are communicably connected via a network,
A specifying unit that specifies a concealment degree to which position information in each of the terminal devices should be concealed based on history information including position information measured by each of the terminal devices;
A generation unit configured to generate open position information in which current position information in each of the terminal devices is adjusted based on the degree of secrecy of each of the terminal devices specified by the specifying unit;
A providing unit that provides the public position information of each of the terminal devices generated by the generation unit to the other terminal devices forming a group;
And the like.

  According to the present invention, location information can be appropriately disclosed while protecting privacy.

FIG. 1 is a block diagram showing an example of the entire configuration of a group communication system according to an embodiment of the present invention. It is a schematic diagram which shows an example of the management information memorize | stored in management DB. FIG. 2 is a block diagram showing an example of a schematic configuration of a typical information processing apparatus in which a management server and a user terminal are realized. It is a block diagram showing a schematic structure of a user terminal concerning this embodiment. It is a schematic diagram which shows an example of user information. (A) is a schematic diagram which shows an example of the map image displayed on the user terminal of the user X, (b) is a schematic diagram which shows an example of the map image displayed on the user terminal of the user Y. FIG. It is a flowchart for demonstrating the open location information notification process which concerns on this embodiment. It is a flowchart for demonstrating the open position information manual change process which concerns on this embodiment. (A), (b) is a schematic diagram for demonstrating the mode of operation at the time of changing a publication | presentation positional information manually. It is a block diagram which shows the outline | summary structure of the management server which concerns on other embodiment. It is a schematic diagram which shows an example of the user setting information memorize | stored in management DB.

Hereinafter, embodiments of the present invention will be described. In the following, an embodiment in which the present invention is applied to a group communication system using a smartphone or the like will be described to facilitate understanding, but in addition to this, for example, a notebook type personal computer, a game device, a PDA (Personal The present invention can be similarly applied to an information processing apparatus such as Digital Assistant).
That is, the embodiments described below are for the purpose of illustration, and do not limit the scope of the present invention. Therefore, although one skilled in the art can adopt an embodiment in which each or all of these elements are replaced with equivalent ones, these embodiments are also included in the scope of the present invention.

(overall structure)
In the group communication system 100 according to the embodiment of the present invention, as shown in FIG. 1, the management server 200 and the management DB 300 are connected, and the management server 200 and the user terminal 400 via the Internet 900. It is configured to be communicably connected.
Although simplified in the drawing, it is assumed that a large number of user terminals 400 exist depending on the user who uses them.

  The management server 200 is, for example, a server device (computer for server) or the like, and groups each user terminal 400 (more specifically, a user who operates the user terminal 400) using the management DB 300, and a message in the group And share location information.

The management DB 300 is a database necessary to manage group communication, and stores management information 301 and the like.
For example, as shown in FIG. 2, the management information 301 includes a user ID 301a, a nickname 301b, an icon ID 301c, a group ID 301d, a current position 301e, and message information 301f.
The icon ID 301 c is identification information of an icon displayed to indicate the current position of another user terminal 400 in a map screen (map screen displayed on the user terminal 400) described later. The group ID 301 d is identification information of a group to which the user belongs (in the case where the user belongs to a plurality of groups, a plurality of identification information). The current position 301 e is open position information, which will be described later, and is information obtained by appropriately adjusting the position information measured by the user terminal 400. The message information 301 f is information for accumulating messages transmitted and received among users in a group.

  Note that such a management DB 300 may be included in the management server 200. That is, the management server 200 may be provided with a storage unit (a storage device 504 or the like to be described later), and the storage unit may manage the management information 301.

  Returning to FIG. 1, the user terminal 400 is, for example, a smart phone etc., accesses the management server 200 via the Internet 900, and other user terminals 400 (more specifically, other user terminals 400 in the same group) Receive a message sent from the terminal, or transmit a message directed to another user terminal 400. In addition, the user terminal 400 accesses the management server 200, receives the disclosure position information of the other user terminal 400 (the current position 301e in the management information 301 described above), and transmits the disclosure position information of itself. As described later, the public location information of one's own is appropriately adjusted in consideration of the concealed area to be concealed such as home, school, work, etc. and the degree of concealment (the degree to which the concealed area should be concealed). There is.

(Schematic Configuration of Information Processing Apparatus)
A management server 200 according to an embodiment of the present invention and a typical information processing apparatus 500 in which the user terminal 400 is realized will be described.

  As shown in FIG. 3, the information processing apparatus 500 includes a central processing unit (CPU) 501, a read only memory (ROM) 502, a random access memory (RAM) 503, a storage device 504, and a display device 505. A communication device 506, an operation device 507, and a positioning device 508 are provided.

  The CPU 501 controls the overall operation of the information processing apparatus 500, is connected to each component, and exchanges control signals and data.

  An IPL (Initial Program Loader) to be executed immediately after power on is recorded in the ROM 502, and when this is executed, a predetermined program is read to the RAM 503, and execution of the program by the CPU 501 is started.

  A RAM 503 is used to temporarily store data and programs, and retains programs and data read from the storage device 504, and other data necessary for communication.

  The storage device 504 is a solid state drive (SSD), a hard disk, or the like, and stores various data. For example, the storage device 504 stores an operating system program, various applications, accompanying data, and the like necessary for controlling the operation of the entire information processing apparatus 500.

  The display device 505 includes, for example, a display device such as a liquid crystal display (LCD), a video random access memory (VRAM) storing image information to be displayed on the display device, and image processing for processing the image information. It is comprised including a part. The image processing unit processes the data read from the storage device 504 and the data processed by the CPU 501, and stores the processed data in the VRAM to generate image information.

  The communication device 506 performs wireless communication using a mobile communication network or a wireless LAN. The communication device 506 may perform wired communication using a wired LAN or the like.

  The operation device 507 is a touch screen, a touch pad, a button, a keyboard, a mouse, or the like, and receives an operation of the user. Note that the user's operation may be accepted by voice.

The positioning device 508 receives, for example, signals transmitted from a plurality of GPS (Global Positioning System) satellites, and measures the current position of the information processing device 500 at predetermined timings.
Note that instead of using such GPS satellites, the positioning device 508 may measure the current position of the information processing device 500 using radio wave strength (reception strength and the like) from a plurality of base stations.

Hereinafter, the configuration and the like of the user terminal 400 realized in the information processing apparatus 500 will be described with reference to FIGS. 4 to 6. When the information processing apparatus 500 is powered on, a program to function as the user terminal 400 (terminal apparatus according to the present invention) is executed, and the user terminal 400 according to the present embodiment is realized.
The management server 200 is similarly realized in the information processing apparatus 500, and as will be described later, necessary processing is also performed in the management server 200. Here, with respect to the most characteristic user terminal 400 in the present embodiment, explain.

(Outline configuration of user terminal)
FIG. 4 is a schematic view showing a schematic configuration of the user terminal 400 according to the present embodiment. As illustrated, the user terminal 400 includes an operation reception unit 410, a transmission / reception unit 420, a storage unit 430, a control unit 440, and a display unit 450.

The operation accepting unit 410 accepts various operations from the user. For example, the operation receiving unit 410 receives an operation from the user based on, for example, information obtained from a touch screen or the like.
The operation device 507 or the like described above can function as such an operation reception unit 410.

The transmission / reception unit 420 accesses the management server 200 via the Internet 900, receives a message sent from another user terminal 400 (more specifically, another user terminal 400 in the same group), or receives another user Send a message to the terminal 400. In addition, the user terminal 400 accesses the management server 200 and receives the disclosure position information of the other user terminal 400, and the disclosure position information of itself (the disclosure position information generated by the disclosure position information generation unit 443 described later) Send
Note that the above-described communication device 506 or the like can function as such a transmission / reception unit 420.

  The storage unit 430 stores, for example, user information 431, position information group 432, open position information 433, and message information 434.

The user information 431 is information on the user operating the user terminal 400, and includes information as shown in FIG. 5 as an example.
That is, the user information 431 includes the user ID 431a, the password 431b, the concealed area 431c, the concealment degree 431d, and the like.
Note that the secret area 431 c is information (for example, a rectangular shape) indicating the range of the area (for example, a place such as a home, a school, a work place or the periphery thereof) specified as the area to be concealed by the secret area identification unit 442 described later. Upper left position and lower right position in the range of In addition, the degree of confidentiality 431 d is a value (for example, a value of 1 to 10, 1 being the lowest and 10 the highest) indicating the degree of confidentiality with respect to the confidential area 431 c.

Returning to FIG. 4, the position information group 432 is information in which the current position (that is, unadjusted position information) of the user terminal 400 measured by the positioning unit 441 described later is accumulated. In the position information group 432, information corresponding to the latest fixed period (for example, one month) is stored in association with the date and time of positioning (more specifically, the date and time to the second). That is, from the position information group 432, the movement trajectory (movement history) of the user within a predetermined period can be traced.
Also, the disclosure position information 433 is disclosure position information on another user terminal 400 (more specifically, another user terminal 400 in the same group) received from the management server 200. The release position information 433 may also store release position information of the own terminal (release position information generated by the release position information generation unit 443).
The message information 434 is information for accumulating a message received from the management server 200 or a message sent to the management server 200 addressed to another user terminal 400. That is, it is information of a message stored on the user terminal 400 side.

In addition to this, the storage unit 430 also stores map data, icon data, and the like necessary for generating a map screen to be described later.
The above-described RAM 503, the storage device 504, and the like can function as such a storage unit 430.

  Control unit 440 controls the entire user terminal 400. The control unit 440 includes, for example, a positioning unit 441, a hidden area specifying unit 442, an open position information generating unit 443, a screen generation unit 444, a correlation specifying unit 445, a group management unit 446, and the like.

The positioning unit 441 measures the position information of the user terminal 400. For example, the positioning unit 441 receives signals transmitted from a plurality of GPS satellites every predetermined time (10 seconds as an example), and detects the correct current position of the user terminal 400. In addition to the signals from such GPS satellites, the positioning unit 441 detects the current position according to the strength of a plurality of radio waves transmitted from a mobile communication base station, a wireless communication access point, or the like. May be
The positioning unit 441 stores the measured position information in the storage unit 430 (position information group 432) in association with the measured date and time.

The concealed area identifying unit 442 identifies the concealed area to be concealed and the degree of concealment. For example, the secret area identification unit 442 statistically processes the information for a fixed period accumulated in the position information group 432, and is an area that is visited frequently to a certain degree, and the average and median values of the stay time are defined time (as an example The area longer than 3 hours) is determined to be a place such as a home, a school, a work place or the vicinity thereof, and specified as a confidential area to be concealed. At that time, the concealed area identifying unit 442 identifies a concealed area such as a home, a school, a work, etc. in consideration of the day of the week, a public holiday, the time, etc., and according to the home, the school, the work etc. Identify
Specifically, normally, areas that visit frequently during the daytime on weekdays and have a long stay time are identified as secret areas because they are schools and offices, and the degree of secrecy is specified as 8 (higher value) Ru. In addition, regions that are frequently visited regardless of weekdays and holidays, and have a long stay time in the time zone including night, are homes, so they are identified as secret areas and the degree of concealment is identified as 10 (maximum value). In addition, if it is a user who works at night, etc., since the day and the night are reversed, the concealed area identification unit 442 determines, for example, the workplace and the home from the length of stay, etc., and conceals them. Identify as a region etc. In addition, without specifically determining home, school, work, etc., areas that satisfy certain conditions are identified as concealed areas, and the degree of concealment is identified according to the number of times of visits, the cumulative stay time, etc. It is also good.
The concealed area identifying unit 442 stores information indicating the identified range of the concealed area in the concealed area 431 c in the user information 431 and stores a value indicating the identified concealment degree in the concealment degree 431 d.

The open position information generation unit 443 appropriately adjusts the position information measured by the positioning unit 441 according to the concealed area 431 c and the concealment degree 431 d to generate open position information.
For example, the open position information generation unit 443 determines whether the position information (that is, the current position) measured by the positioning unit 441 is in any of the concealed areas 431c in the user information 431, and any of the concealed areas If it is determined that the position is within 431 c, the position information determined by the positioning unit 441 is shifted by a predetermined value according to the corresponding degree of concealment 431 d, and open position information adjusted to be outside the concealed area is generated.
The adjustment method of the position information, for example, randomly selects latitude and longitude (or both) in the position information, and randomly adds / subtracts a predetermined value corresponding to the confidentiality degree 431 d (corresponding concealment degree 431 d) to / from that value. Generate public location information shifted out of the secret area. In addition, the adjustment method of position information is not limited to such a method of performing addition and subtraction randomly, and can be changed as appropriate. For example, the disclosure position information adjusted so as to be outside the concealed area may be generated by shifting a predetermined direction according to the degree of concealment 431 d in a predetermined direction. Alternatively, only the azimuth may be randomly determined, the azimuth may be shifted by a predetermined value according to the degree of concealment 431d, and release position information adjusted to be outside the concealed area may be generated. Other than this, position information (outside the secret area) which has been measured in the past may be used as the open position information. In this case, privacy is protected by providing a time lag. Also, the open position information may be generated by shifting the position information from the measured position information at random (such as λ of Poisson distribution).
Also, if the position information measured by the positioning unit 441 is out of range from any of the concealed areas 431c from the beginning, the open position information generation unit 443 does not adjust the position information, and is used as the open position information as it is. Do. In addition, even if the measured position information is out of the range of the concealed area 431c, if the moving direction of the user (user terminal 400) is directed to the concealed area 431c, the disclosed position information generation unit 443 determines the degree of concealment The adjusted release position information may be generated by using some value of 431 d or the like. For example, when a certain distance is away from the concealed area 431c, the disclosure position information generation unit 443 generates disclosure position information adjusted using a value of 1/10 of the degree of concealment degree 431d, and eventually, the concealment area As the 431 c is approached, the disclosure position information adjusted using values with an increased ratio such as 1/5, 1/2, 3/4 of the confidentiality degree 431 d is generated, etc. Even if it exists, you may generate the publication position information adjusted suitably.

In addition to this, the open position information generation unit 443 unconditionally sets the position information measured by the positioning unit 441 to a predetermined amount (for example, a value arbitrarily set by the user even if it is out of the range of the concealed area 431c). Minute) shifted public location information may be generated.
Thus, the disclosure position information generated by the disclosure position information generation unit 443 is transmitted to the management server 200 by the transmission / reception unit 420, and the current position 301e (target current position 301e) in the management information 301 of FIG. 2 described above. Is stored as

The screen generation unit 444 generates various screens for group communication. For example, the screen generation unit 444 generates a map screen as shown in FIGS. 6 (a) and 6 (b).
FIG. 6A is an example of a map screen generated by the screen generation unit 444 of the user terminal 400 of the user X (nickname “ΔΔ flower child”). On the other hand, FIG. 6B is an example of a map screen generated by the screen generation unit 444 of the user terminal 400 of the user Y (nickname “○ Taro”).
That is, the screen generation unit 444 arranges the icons of the other user terminals 400 excluding the own terminal in the same group at corresponding positions on the map based on the disclosure position information 433 stored in the storage unit 430. Generate a map screen. That is, in the user terminal 400 of the user X, as shown in FIG. 6A, the screen generation unit 444 displays the icon ICO1 of the user Y and the icon ICO2 of the user Z (nickname “□□ Saburo”) respectively. In accordance with the disclosed position information, the map screen is displayed on which the messages MSG1 and MSG2 exchanged between the user Y and the user X are displayed while being arranged at the corresponding position on the map.

On the other hand, in the user terminal 400 of the user Y, as shown in FIG. 6B, the screen generation unit 444 displays the icon ICO3 of the user X and the icon ICO2 of the user Z according to the respective disclosure position information. It arrange | positions on the corresponding position on a map, and the map screen which displayed message MSG1, MSG2 exchanged between the user Y and the user X is produced | generated.
In FIG. 6B, as an example, even when user X's home is at the position indicated by point A in the figure and user X is at home with his own user terminal 400, the user terminal of user Y At 400, a map screen is displayed in which the icon ICO3 of the user X is disposed at a position largely deviated from the point A. For example, in the user terminal 400 of the user X, the point A and the periphery thereof are stored in the concealed area 431 c, and 10 (maximum value) is stored in the corresponding concealment degree 431 d. Therefore, the disclosure position information generation unit 443 generates the disclosure position information adjusted to be outside the concealed area by largely shifting the positioned position information according to the degree of concealment 431d. Then, after the disclosure position information adjusted in such a manner is sent to the management server 200, the disclosure position information is sent to the user terminal 400 of the user Y and stored in the storage unit 430 as the disclosure position information 433 of the user X.
Therefore, in the user terminal 400 of the user Y, the screen generation unit 444 displays the map screen in which the icon ICO3 of the user X is disposed at a position largely deviated from the point A as shown in FIG. become.

  Although the icons ICO1 to ICO3 are used to represent the position of the user in the example of FIGS. 6A and 6B, the position of the user may be represented using another image. For example, the user's position may be represented using another image such as a user's face image (face photograph), pictograms, symbols, and the like.

  Returning to FIG. 4, the correlation specifying unit 445 may, for example, determine the frequency (for example, the number of messages per unit time) of messages exchanged between users (between the own terminal and another user terminal 400). The strength of the correspondence between the users (that is, the closeness) is calculated by appropriately analyzing the contents of the above, and the correlation between the users is specified based thereon.

The group management unit 446 creates a new group or cancels the group according to the correlation identified by the correlation identification unit 445.
For example, when the closeness between the correlated users (the own terminal and the other user terminal 400) specified by the correlation specifying unit 445 exceeds the reference value, the own terminal and the other user terminal 400 are newly added. Into separate groups (split into separate groups).
Also, conversely, when the closeness between the users who have already configured the group (the own terminal and the other user terminal 400) falls below the minimum value, the group management unit 446 cancels the group. The target of releasing the group may be limited to the group automatically created by the group management unit 446.

  In addition, when the closeness between the correlated users (the own terminal and the other user terminal 400) specified by the correlation specifying unit 445 exceeds the reference value, the open position information generation unit 443 described above For the other user terminals 400, the disclosure position information may be generated by adjusting the value of the degree of concealment 431d.

  In this case, in order to create a new group from the correlation between users (between the own terminal and another user terminal 400), for example, a small group is automatically selected from among a large group according to closeness User-friendliness is improved, such as being generated. Moreover, since the value of the degree of secrecy is automatically changed according to closeness or the like, usability is further improved.

In addition to this, control unit 440 appropriately performs a process of displaying a menu, changing a screen display, and the like according to the operation accepted by operation accepting unit 410.
The CPU 501, the positioning device 508, and the like described above can function as the control unit 440 configured as described above.

The display unit 450 displays the map screen and the like generated by the screen generation unit 444 described above. That is, if it is the user terminal 400 of the user X, the display unit 450 displays a map screen as shown in FIG. If the user terminal 400 is the user Y, the display unit 450 displays a map screen as shown in FIG.
Note that the display device 505 or the like described above can function as such a display unit 450.

(Operation of user terminal)
Hereinafter, the operation of the user terminal 400 having such a configuration will be described with reference to FIG.
FIG. 7 is a flowchart showing the flow of the disclosed position information notification process according to the present embodiment. In addition, a secret area such as a home, a school, and a work place in user terminal 400 and a concealment degree have already been identified, and information indicating the range of the concealed area is stored in concealment area 431 c of user information 431. It is assumed that a value indicating the degree is stored in 431 d.

First, the user terminal 400 measures position information (step S11).
That is, control unit 440 (positioning unit 441) receives signals sent from a plurality of GPS satellites, and detects the correct current position of user terminal 400.

The user terminal 400 determines whether the measured position information is within the secret area (step S12).
That is, control unit 440 determines whether or not the position information (that is, the current position of user terminal 400) measured in step S11 is in any of secret areas 431c.

When the user terminal 400 determines that the measured position information is within the secret area (step S12; Yes), the user terminal 400 adjusts the position information according to the degree of concealment corresponding to the secret area to generate open position information. (Step S13).
That is, control unit 440 (release position information generation unit 443) shifts the position information measured in step S11 by a predetermined value according to concealment degree 431d, and generates release position information adjusted to be outside the concealed area. .
Specifically, the control unit 440 randomly selects the latitude and longitude (or both) in the position information, randomly adds and subtracts a predetermined value according to the degree of concealment 431 d to or from that value, and shifts the position outside the concealed area Generate information. In addition to this, the control unit 440 may generate disclosure position information that is adjusted to be outside the concealed area by shifting the predetermined direction according to the concealment degree 431 d in a predetermined direction. Alternatively, only the azimuth may be randomly determined, the azimuth may be shifted by a predetermined value according to the degree of concealment 431d, and release position information adjusted to be outside the concealed area may be generated. In addition, position information (outside the secret area) positioned in the past may be used as the open position information. In this case, privacy is protected by providing a time lag. Also, the open position information may be generated by shifting the position information from the measured position information at random (such as λ of Poisson distribution).

On the other hand, when it is determined that the measured position information is not within the concealed area (is outside the concealed area) (step S12; No), the user terminal 400 directly uses the position information measured in step S11 as the disclosed position information. (Step S14).
That is, since the control unit 440 is outside the secret area, the control unit 440 sets the position information as it is as the open position information without adjusting it.
If the movement direction of the user (user terminal 400) is directed to the secret area 431c even if the measured position information is out of the range of the secret area 431c, the control unit 440 determines what the degree of concealment 431d is. The adjusted release position information may be generated using, for example, the value of the rule. For example, when a certain distance is away from the concealed area 431 c, the control unit 440 generates open position information adjusted using a value of 1/10 of the concealed degree 431 d, and eventually approaches the concealed area 431 c. As a result, the disclosure location information adjusted using values obtained by increasing the ratio, such as 1/5, 1/2, and 3/4 of the degree of confidentiality 431 d, may be generated, etc., even if it is outside the range of the confidential area 431 c. The published position information adjusted appropriately may be generated.
In addition to this, even if the control unit 440 is out of the range of the secret area 431 c, the control unit 440 may generate open position information unconditionally shifting the position information measured by the positioning unit 441 by a predetermined amount.

The user terminal 400 transmits the generated open position information to the management server 200 (step S15).
In other words, control unit 440 can adjust the position information to the open position information (for example, the open position information shifted from within the concealed area to the outside of the hidden area) or the open position information as the position information (for example, the hidden area from the beginning) The external disclosure position information) and the like are transmitted to the management server 200 through the transmission / reception unit 420.

The user terminal 400 determines whether an application for group communication (application program) has ended (step S16).
If the user terminal 400 determines that the application has not ended (Step S16; No), the process returns to Step S11 described above.

  On the other hand, when it is determined that the application has ended (step S16; Yes), the user terminal 400 ends the disclosure position information notification process of FIG. 7.

With such open position information notification processing, the degree of concealment in which the position information in the user terminal 400 should be concealed is specified based on the history information including the position information, and based on the degree of concealment, the position information which is the current position is Adjustments are made as appropriate, and public location information is generated. For example, if the position information is within the concealed area of the user, the disclosed position information shifted out of the concealed area according to the degree of concealment is generated and transmitted to the management server 200.
Then, when such open position information is sent to another user terminal 400 and a map screen is generated, for example, as shown in FIG. 6 (b), it deviates greatly from a secret area (point A at home). The icon ICO3 is displayed at the position on the map. Therefore, it becomes extremely difficult for another user to predict the other party's (nickname “ΔΔ Hanako”) 's home.

  As a result, location information can be appropriately disclosed while protecting privacy.

In the above embodiment, as shown in FIGS. 6 (a) and 6 (b), only the icons of the other users (other user terminals 400) are arranged and displayed on the map, and the own icon (the icon of the own terminal Although the case where) is not displayed has been described, the own icon may be displayed on the map screen together with the icons of other users. Then, the disclosure position information of the own terminal may be changed according to the user moving the own icon arbitrarily.
Hereinafter, processing when changing the disclosure position information of the own terminal according to the moved own icon will be described with reference to FIG.

  FIG. 8 is a flowchart showing the flow of the open position information manual change process according to the present embodiment. In order to facilitate the description, the user X has just started using the group communication system 100 (only recently joined the group of user Y and user Z), and a secret area etc. has not yet been identified. The following description will be given assuming that (the concealed area 431 c and the concealment degree 431 d are blank).

First, the user terminal 400 displays its own icon at the corresponding position on the map according to the disclosure position information (that is, the disclosure position information of the own terminal) transmitted to the management server 200 (step S21).
For example, in the user terminal 400 of the user X, the control unit 440 is, as shown in FIG. 9A, based on the disclosure position information (at this point, the position information becomes the disclosure position information as it is). Display the icon ICO4 at the corresponding position on the map.
FIG. 9A is an example of a map screen generated by the screen generation unit 444 of the user terminal 400 of the user X (nickname “ΔΔ flower child”). That is, in the user terminal 400 of the user X, the screen generation unit 444 opens the icon ICO1 of the user Y (nickname "○ Taro") and the icon ICO2 of the user Z (nickname "□□ Saburo") to each other According to position information, while arrange | positioning in the corresponding position on a map, according to the open position information of an own terminal, the map screen which arrange | positions the self-icon ICO4 in the corresponding position on a map is produced | generated.

Returning to FIG. 8, the user terminal 400 determines whether or not there has been an operation on the own icon (step S <b> 22).
That is, control unit 440 determines whether operation accepting unit 410 has accepted a flick operation or the like to self icon ICO 4 as shown in FIG. 9A.
If the user terminal 400 determines that there has been no operation to the own icon (step S22; No), the process proceeds to step S26 described later.

On the other hand, when it is determined that there has been an operation on the own icon (Step S22; Yes), the user terminal 400 changes the disclosure position information according to the amount of movement of the own icon (Step S23).
For example, as shown in FIG. 9B, when the own icon ICO 4 is moved from the point A, which is the original arrangement position, as shown by the arrow, the control unit 440 changes the disclosure position information by the amount of the movement. Do.

Further, in response to the movement of the icon ICO 4 itself, the control unit 440 registers information on the concealed area and the degree of concealment (step S24).
For example, the concealed area identifying unit 442 registers, in the concealed area 431c, the range indicating the point A, which is the original arrangement position, and its periphery, and registers a value corresponding to the movement amount of the own icon ICO4 in the concealment degree 431d. . As described above, since the point A and the periphery thereof are registered in the concealed area 431c and the degree to be concealed is also registered in the concealment degree 431d, if the position information thus measured is within the concealed area, the position information is The disclosure position information is generated that is shifted according to the degree of secrecy 431 d and adjusted to be outside the secrecy area.

  Returning to FIG. 8, the user terminal 400 transmits the changed disclosure position information to the management server 200 (step S25).

The user terminal 400 determines whether the application of group communication has ended (step S26).
If the user terminal 400 determines that the application has not ended (Step S26; No), the process returns to Step S21 described above.

  On the other hand, when it is determined that the application has ended (step S26; Yes), the user terminal 400 ends the disclosure position information manual change process of FIG.

  According to such a disclosure position information manual change process, the user can easily change the disclosure position information by operating the own icon. For example, even when the user's current position (public position information) is not registered as a secret area, etc., the public position information can be freely changed and registered as a secret area according to the manual operation. In addition, by displaying the own icon, it is possible for the user terminal 400 on the opposite side to know at which position on the map the own icon is arranged on the map, so that when the message is exchanged, the habit does not fit Nothing happened.

  Thus, in the user terminal 400 of the present embodiment, location information can be appropriately disclosed while protecting privacy.

(Other embodiments)
In the above embodiment, the case where each user terminal 400 generates its own disclosure position information has been described, but the management server 200 may appropriately generate disclosure position information of each user terminal 400. .

  FIG. 10 is a block diagram showing an example of a schematic configuration of a management server 200 according to another embodiment. The management server 200 manages group communication using the management DB 300 and appropriately generates open position information of each user terminal 400.

In FIG. 10, the management DB 300 stores management information 301, user setting information 302, and the like.
The management information 301 has the same configuration as that of FIG. 2 described above. In addition, as the current position 301e, as will be described later, a position appropriately generated by the management server 200 (public position information generation unit 232) is stored.

Further, as shown in FIG. 11, the user setting information 302 includes a user ID 302a, a position information group 302b, a concealed area 302c, and a concealment degree 302d.
The position information group 302 b is information in which position information (correct current position) transmitted from the user terminal 400 is stored for each user terminal 400. In the position information group 302b, information for the last fixed period (for example, one month) is accumulated in association with the date and time of positioning (more specifically, the date and time up to the second). That is, from this position information group 302b, the movement trajectory (movement history) of the user within a fixed period can be traced for each user terminal 400.
In addition, as described later, the secret area 302 c is a range of a secret area (for example, a place such as a home, a school, a work place or the periphery thereof) specified according to each user by the management server 200 (the secret area specification unit 231). Information (as one example, upper left point position and lower right point position in the range of a rectangular shape).
The degree of secrecy 302d is a value (for example, a value of 1 to 10, 1 being the lowest and 10 the highest) indicating the degree of secrecy of the secrecy area 302c.

  Note that such a management DB 300 may be included in the management server 200. That is, the management server 200 may be provided with a storage unit (the storage device 504 in FIG. 3 and the like described above), and the storage unit may manage the management information 301 and the user setting information 302.

  Returning to FIG. 10, the management server 200 includes a receiving unit 210, a transmitting unit 220, and a control unit 230.

The receiving unit 210 receives various information sent from the user terminal 400 via the Internet 900.
For example, the receiving unit 210 sequentially receives position information (unadjusted position information) sent from each user terminal 400. The received position information is accumulated in position information group 302b (position information group 302b corresponding to the user) in the user setting information 302 in FIG. In addition to this, the receiving unit 210 also receives a message or the like addressed to another user terminal 400 from the user terminal 400.

The transmission unit 220 transmits various types of information to the user terminal 400 via the Internet 900.
For example, the transmitting unit 220 transmits, to the user terminal 400, the disclosure position information generated by the disclosure position information generating unit 232 described later. In addition to this, the transmission unit 220 also transmits a message or the like from another user terminal 400 to the user terminal 400.

  The control unit 230 controls the entire management server 200. The control unit 230 includes, for example, a hidden area specifying unit 231, an open position information generating unit 232, a correlation specifying unit 233, a group management unit 234, and the like.

The concealed area identifying unit 231 identifies, for each user, the concealed area to be concealed and the concealment degree thereof. For example, the concealed area identifying unit 231 performs statistical processing on the information for a fixed period accumulated in the position information group 302b in the user setting information 302 in FIG. A region where the median is longer than a prescribed time (for example, 3 hours) is determined to be a place such as a home, a school, a work place or the periphery thereof, and is specified as a hidden region to be concealed. At that time, the concealed area identifying unit 231 identifies a concealed area such as a home, a school, a work, etc. in consideration of the day of the week, a public holiday, the time, etc., and according to the home, the school, the work etc. Identify
Specifically, normally, areas that visit frequently during the daytime on weekdays and have a long stay time are identified as secret areas because they are schools and offices, and the degree of secrecy is specified as 8 (higher value) Ru. In addition, regions that are frequently visited regardless of weekdays and holidays, and have a long stay time in the time zone including night, are homes, so they are identified as secret areas and the degree of concealment is identified as 10 (maximum value). In addition, if it is a user who works at night, etc., since the day and night are reversed, the concealed area identification unit 231 determines, for example, the workplace and the home from the length of stay, etc., and conceals them. Identify as a region etc. In addition, without specifically determining home, school, work, etc., areas that satisfy certain conditions are identified as concealed areas, and the degree of concealment is identified according to the number of times of visits, the cumulative stay time, etc. It is also good.
The concealed area identifying unit 231 stores information indicating the identified range of the concealed area in the concealed area 302 c in the user setting information 302 and stores a value indicating the identified concealment degree in the concealment degree 302 d.

The disclosure position information generation unit 232 appropriately adjusts the position information sent from the user terminal 400 according to the concealed area 302 c and the degree of concealment 302 d for each user terminal 400, and generates disclosure position information.
For example, the open position information generation unit 232 determines whether the position information (that is, the current position of the user terminal 400) sent from the user terminal 400 is in the secret area 302c (in the secret area 302c of the user). If it discriminate | determines and it discriminate | determines that it is in the secret area 302c, the position information received from the user terminal 400 will be shifted by the predetermined value according to the corresponding concealment degree 302d, and the open position information adjusted to be outside the secret area will be generated. .
The adjustment method of the position information, for example, randomly selects latitude and longitude (or both) in the position information, and randomly adds or subtracts a predetermined value corresponding to the degree of concealment 302d (corresponding degree of concealment 302d) to that value. Generate public location information shifted out of the secret area. In addition, the adjustment method of position information is not limited to such a method of performing addition and subtraction randomly, and can be changed as appropriate. For example, the disclosure position information adjusted so as to be outside the concealed area may be generated by shifting a predetermined direction according to the degree of secrecy 302d in a predetermined direction. Alternatively, only the azimuth may be randomly determined, the azimuth may be shifted by a predetermined value according to the degree of secrecy 302d, and release position information adjusted to be outside the concealed area may be generated. Other than this, position information (outside the secret area) which has been measured in the past may be used as the open position information. In this case, privacy is protected by providing a time lag. Also, the open position information may be generated by shifting the position information from the measured position information at random (such as λ of Poisson distribution).
Also, if the position information sent from the user terminal 400 is out of range from any concealed area 302 c (any concealed area 302 c of the user) from the beginning, the disclosed position information generation unit 232 determines the position information Without adjusting it, as it is with public location information. In addition, even if the measured position information is out of the range of the concealed area 302c, if the moving direction of the user (user terminal 400) is directed to the concealed area 302c, the disclosed position information generation unit 232 determines the degree of concealment The adjusted disclosure position information may be generated by using, for example, some value of 302 d. For example, when a certain distance is away from the concealed area 302c, the disclosure position information generation unit 232 generates disclosure position information adjusted using a value of 1/10 of the degree of secrecy 302d, and eventually, the concealed area The public location information is adjusted using values obtained by increasing the ratio, such as 1/5, 1/2, 3/4 of the degree of secrecy 302d, as it gets closer to 302c, etc. Even if it exists, you may generate the publication position information adjusted suitably.
In addition to this, the open position information generation unit 232 may generate open position information obtained by unconditionally shifting the position information received from the user terminal 400 by a predetermined amount even if it is out of the range of the secret area 302c. .
Thus, the disclosure position information generated by the disclosure position information generation unit 232 is stored as the current position 301 e (the current position 301 e of the object) in the management information 301 of FIG. 2 described above, and then belongs to the same group. Are transmitted to user terminals 400 of other users.

  The correlation specifying unit 233 responds to the user, for example, by appropriately analyzing the frequency of messages exchanged between users (the user terminals 400) (for example, the number of messages per unit time) and the content of the message. The strength of the relationship (that is, closeness) is calculated, and based on it, the correlation between users is specified.

The group management unit 234 creates a new group or cancels the group according to the correlation identified by the correlation identification unit 233.
For example, when the closeness between the correlated users (the user terminals 400) specified by the correlation specifying unit 233 exceeds the reference value, the users are divided into new groups (the groups are divided into different groups). ).
Also, conversely, when the closeness between the users (the user terminals 400) who have already formed the group falls below the minimum value, the group management unit 234 cancels the group. The target of releasing the group may be limited to the group automatically created by the group management unit 234.

That is, the group management unit 234 adds a newly assigned group ID to the group ID 301 d in the management information 301 of FIG. 2 for each user whose familiarity exceeds the reference value. At this time, the group management unit 234 may set the group ID to be numbered to a special number system so that it can be identified from the group ID that the group has high affinity.
For each user terminal 400 belonging to a group having such high closeness, the above-mentioned open position information generation unit 232, for example, lowers the value of the degree of secrecy 302d, and even if they are within the secrecy area, Some degree of accurate published location information may be generated. That is, when the closeness between users increases, the value of the degree of secrecy 302d is automatically lowered, and even when each other is in the secrecy area, the disclosure position information is sent to the other party with high accuracy up to a certain degree It will be.

As described above, also in the other embodiments, the degree of concealment in which the position information in the user terminal 400 should be concealed is specified based on the history information including the position information, and the position information indicating the current position is appropriately determined based on the degree of concealment The adjustment is performed, and the management server 200 generates the disclosure position information. For example, if the position information is within the concealed area of the user, open position information shifted outside the concealed area according to the degree of concealment is generated and transmitted to another user terminal 400.
Then, in the other user terminal 400, for example, as shown in FIG. 6B, the icon ICO3 is displayed at a position on the map that is largely deviated from the secret area (point A at home). Therefore, it becomes extremely difficult for another user to predict the other party's (nickname “ΔΔ Hanako”) 's home.
As a result, location information can be appropriately disclosed while protecting privacy.

  Moreover, in order to create a new group from the correlation between users (the user terminals 400), for example, a small group is automatically generated according to closeness among large groups, etc. Improve. Moreover, since the value of the degree of secrecy is automatically changed according to closeness or the like, usability is further improved.

In the above embodiment, the case where the disclosure position information generation unit 443 and the disclosure position information generation unit 232 generate disclosure position information whose position information is appropriately adjusted has been described, but such adjusted disclosure position information Instead of using it, the size when displaying the icon may be changed to protect privacy.
For example, in the secret area, the size of the icon may be displayed large to make it difficult to understand the position on the map represented by the icon.

  Although the above embodiment has described the case of using the dedicated user terminal 400 and the management server 200, an operation program for defining the operation of such a user terminal 400 and the management server 200 may be an existing personal computer, an information terminal device, etc. It is also possible to cause the personal computer to function as the user terminal 400 or the management server 200 by applying to

  Also, the distribution method of such a program is arbitrary, and may be distributed by being stored in a computer readable recording medium such as a CD-ROM, a DVD, a MO (Magneto Optical Disc), a memory card, etc. It may be distributed via a communication network such as the Internet.

(Summary)
The group communication system according to the first aspect of the present invention is a group communication system in which a plurality of terminal devices (user terminals such as smart phones) and a server device (management server) are communicably connected via a network. And a specifying unit, a generating unit, and a providing unit.

The identifying unit identifies the degree of concealment of the position information in each of the terminal devices based on the history information including the position information measured by each of the terminal devices. Further, the generation unit generates open position information in which the current position information in each of the terminal devices is adjusted, based on the degree of secrecy of each of the terminal devices specified by the identification unit.
Then, the providing unit provides the open position information of each of the terminal devices generated by the generating unit to the other terminal devices forming the group.

As described above, the degree of concealment in which the position information in the terminal apparatus should be concealed is specified based on the history information including the position information, and the disclosed position information in which the position information that is the current position is appropriately adjusted based on the degree of concealment Is generated. For example, if the position information is within the concealed area of the user (terminal device), the disclosed position information shifted out of the concealed area according to the degree of concealment is generated and transmitted to the other terminal device.
As a result, location information can be appropriately disclosed while protecting privacy.

  A terminal device (user terminal) according to a second aspect of the present invention is a management server that manages group communication between the terminal devices, and each terminal device communicably connected via a network, and the positioning unit , A generation unit, a transmission unit, a reception unit, and a display unit.

  That is, as in the group communication system according to the first aspect, the terminal device according to the second aspect can appropriately disclose position information while protecting privacy.

In the terminal device, the identifying unit identifies the concealed area to be concealed in the own terminal and the concealment degree based on the history information, and the generating unit determines the current position information and the concealed area determined by the positioning unit. The open position information may be generated by adjusting the current position information on the basis of the positional relationship with and the degree of concealment.
In this case, the concealed area to be concealed and the concealment degree are specified, and if the current position information is within the concealed area, it is possible to generate the disclosure position information shifted out of the concealed area according to the concealment degree.

Further, in the above-mentioned terminal device, when the current position information measured by the positioning unit is within the concealed area, the generation unit shifts the current position information according to the degree of concealment and adjusts so as to be outside the concealed area. Public location information may be generated.
In this case, it is possible to generate the disclosure position information appropriately shifted according to the degree of concealment.

In addition, in the terminal device, the generation unit may shift the current position information and adjust the position when the current position information measured by the positioning unit is outside the concealed area but is approaching the concealed area. Information may be generated.
In this case, even outside the secret area, it is possible to generate appropriately shifted public location information.

Further, the terminal device further includes an operation receiving unit for receiving an operation on the image displayed on the display unit, and the display unit further displays an image representing the own terminal on the map based on the disclosure position information generated by the generation unit. When the operation receiving unit receives an operation on the image representing the own terminal, the generation unit may generate the disclosure position information whose position is changed according to the operation.
In this case, the open position information can be easily changed by operating the image representing the own terminal.

Further, in the terminal device, a plurality of terminal devices including the self terminal are compared based on the correlation specifying unit that specifies the correlation between the self terminal and another terminal device, and the correlation specified by the correlation specifying unit. And a group management unit for grouping.
In this case, terminal devices can be grouped automatically.

Further, the terminal device further includes a correlation specifying unit that specifies a correlation between the own terminal and another terminal device, and the generation unit is a terminal having the correlation specified by the correlation specifying unit and the other terminal When the intimacy degree with the device exceeds the reference value, the other terminal device may generate the disclosure position information with a reduced degree of secrecy.
In this case, as the closeness degree is increased, more accurate disclosure location information can be provided to the other party's terminal device.

Further, in the above terminal device, the closeness between the own terminal and another terminal device is specified based on the frequency of messages mutually sent in group communication or the contents of mutually sent messages. May be
In this case, the closeness is determined only by exchanging messages, and the disclosure position information of the accuracy corresponding thereto is transmitted and received.

  A position information notification method according to a third aspect of the present invention is a position information notification in a management server that manages group communication between terminal devices and each terminal device (user terminal) communicably connected via a network. The method comprises positioning, identifying, generating, transmitting, receiving and displaying.

  That is, the location information notification method according to the third aspect can appropriately publish location information while protecting privacy, as in the group communication system according to the first aspect.

  A program according to a fourth aspect of the present invention includes a management server that manages group communication between computers, and a positioning unit, a specifying unit, a generating unit, and a transmitting unit for each computer communicably connected via a network. , Function as a receiver and a display.

  That is, as in the group communication system according to the first aspect, the program according to the fourth aspect can appropriately disclose position information while protecting privacy.

  As described above, according to the present invention, it is possible to provide a group communication system, a terminal device, a position information notification method, and a program capable of appropriately disclosing position information while protecting privacy.

100 group communication system 200 management server 210 reception unit 220 transmission unit 230 control unit 231 concealed area identification unit 232 open position information generation unit 233 correlation identification unit 234 group management unit 300 management DB
301 management information 302 user setting information 400 user terminal 410 operation reception unit 420 transmission / reception unit 430 storage unit 431 user information 432 position information group 433 open position information 434 message information 440 control unit 441 positioning unit 442 concealed area identification unit 443 open position information generation Part 444 Screen generation part 445 Correlation specifying part 446 Group management part 450 Display part 500 Information processing device 501 CPU
502 ROM
503 RAM
504 storage device 505 display device 506 communication device 507 operation device 508 positioning device 900 Internet

Claims (11)

A group communication system in which a plurality of terminal devices and a server device that manages group communication between the terminal devices are communicably connected via a network,
A specifying unit that specifies a concealment degree to which position information in each of the terminal devices should be concealed based on history information including position information measured by each of the terminal devices;
A generation unit configured to generate open position information in which current position information in each of the terminal devices is adjusted based on the degree of secrecy of each of the terminal devices specified by the specifying unit;
A providing unit that provides the public position information of each of the terminal devices generated by the generation unit to the other terminal devices forming a group;
A group communication system comprising: A management server that manages group communication between terminal devices, and each terminal device communicably connected via a network,
A positioning unit that measures position information of the own terminal;
A specifying unit that specifies a concealment degree to which the position information should be concealed in the own terminal based on history information including the position information measured by the positioning unit;
A generation unit configured to generate open position information in which the current position information determined by the positioning unit is adjusted based on the degree of concealment determined by the identification unit;
A transmitter configured to transmit the open position information generated by the generator to the management server;
A receiving unit that receives the open position information about another terminal apparatus sent from the management server;
A display unit for displaying a map screen in which an image representing another terminal device is arranged on a map based on the open position information received by the reception unit;
A terminal device comprising: The specifying unit specifies a concealed area to be concealed in the own terminal and the concealment degree based on the history information;
The generation unit generates open position information in which the current position information is adjusted based on the position relationship between the current position information measured by the positioning unit and the secret area, and the concealment degree.
The terminal device according to claim 2, characterized in that: The generation unit shifts the current position information according to the degree of concealment when the current position information measured by the positioning unit is within the concealed area, and adjusts the position information to be outside the concealed area Generate location information,
The terminal device according to claim 3, characterized in that: The generation unit generates disclosure position information adjusted by shifting the current position information when the current position information measured by the positioning unit is approaching the secret area even if the current position information is outside the secret area Do,
The terminal device according to claim 3, characterized in that: It further comprises an operation accepting unit that accepts an operation on the image displayed on the display unit,
The display unit displays a map screen in which an image representing the own terminal is further arranged on a map based on the open position information generated by the generation unit.
The generation unit generates the disclosure position information whose position is changed according to the operation when the operation reception unit receives an operation on an image representing the own terminal.
The terminal device according to any one of claims 2 to 5, characterized in that: A correlation specifying unit that specifies a correlation between the own terminal and another terminal device;
A group management unit that groups a plurality of terminal devices including an own terminal based on the correlation specified by the correlation specification unit;
The terminal device according to any one of claims 2 to 6, further comprising: And a correlation specifying unit that specifies the correlation between the own terminal and another terminal device,
The generation unit is configured to, when the degree of closeness between the own terminal having a correlation specified by the correlation specifying unit and another terminal apparatus exceeds a reference value, the degree of concealment with respect to the other terminal apparatus Generate public location information with lowered
The terminal device according to any one of claims 2 to 6, characterized in that: The closeness between the own terminal and another terminal apparatus is specified based on the frequency of messages sent to each other in group communication or the contents of messages sent to each other.
The terminal device according to claim 8, characterized in that: A management server that manages group communication between terminal devices, and a method of notifying location information in each terminal device communicably connected via a network,
A positioning step of positioning position information of the own terminal;
A specifying step of specifying a concealment degree to which the position information should be concealed in the own terminal based on history information including the position information measured in the positioning step;
A generation step of generating open position information in which the current position information measured in the positioning step is adjusted based on the degree of concealment specified in the specifying step;
A transmitting step of transmitting the open position information generated in the generating step to the management server;
A receiving step of receiving the open position information about another terminal apparatus sent from the management server;
A display step of displaying a map screen in which an image representing another terminal device is arranged on a map based on the open position information received in the reception step;
A position information notification method comprising: A management server that manages group communication between computers, and each computer communicably connected via a network,
Positioning unit that measures the position information of its own computer,
A specifying unit that specifies a concealment degree to which the position information should be concealed in the own computer based on history information including the position information measured by the positioning unit;
A generation unit configured to generate open position information in which the current position information determined by the positioning unit is adjusted based on the degree of concealment determined by the identification unit;
A transmitter configured to transmit the open position information generated by the generator to the management server;
A receiving unit that receives the open position information about another computer sent from the management server;
A display unit for displaying a map screen in which an image representing another computer is arranged on a map based on the open position information received by the receiving unit;
A program characterized by acting as

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