JP2017182513A - Information leakage prevention system, information leakage prevention method, and mobile terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information leakage prevention technique capable of preventing information from leaking due to a mobile terminal carried around by a worker within an area being brought out.SOLUTION: A management device 3 comprises: a positional information generation unit 44 for generating positional information indicating the position of a mobile terminal 1 on the basis of a radio wave transmitted by the mobile terminal 1; and a positional information transmission unit 43 for transmitting the positional information to the mobile terminal 1. The mobile terminal 1 comprises: a storage unit 15 for storing object information which is an object of information leakage prevention; a positional information receiving unit 16 for receiving the positional information from the management device 3; and a retention delete processing unit 10 for executing a retention delete process to delete the object information retained in the storage unit 15 on the basis of the positional information or its reception state.SELECTED DRAWING: Figure 2

Description

  Embodiments described herein relate generally to an information leakage prevention technology including a portable terminal carried by an operator in an area and a management device that manages the portable terminal.

  2. Description of the Related Art Conventionally, there is a system that supports maintenance work of an operator at a work site such as a plant. Such a support system includes a central support device that stores information related to plant maintenance, and the central support device transmits necessary information to a portable terminal owned by each worker so as to improve work efficiency. I have to.

  In addition, there is a system in which RFIDs storing position data are provided at various locations on the work site, and the position data of the RFID is read by a worker with a portable terminal so that the position of the worker can be specified based on the position data. .

Japanese Patent No. 3477348 Japanese Patent No. 4340580

  In a conventional portable terminal used at a work site, various information such as an image photographed at the work site is stored in addition to information for supporting the work. However, when these pieces of information are confidentiality targets, there is a problem that if the portable terminal is taken out of the work area, the information that is the confidentiality target leaks.

  The embodiment of the present invention has been made in consideration of such circumstances, and an information leakage prevention technique capable of preventing information leakage from being taken out of a portable terminal carried by an operator in an area. The purpose is to provide.

  An information leakage prevention system according to an embodiment of the present invention is an information leakage prevention system including a portable terminal possessed by an operator in an area and a management device that manages the portable terminal, wherein the management device includes the portable device A position information generating unit that generates position information indicating the position of the portable terminal based on radio waves transmitted from the terminal; and a position information transmitting unit that transmits the position information to the portable terminal. Is stored in the storage unit based on the location information or its reception state, a storage unit that stores target information that is subject to information leakage prevention, a location information reception unit that receives the location information from the management device, A storage erasure processing section for executing a storage erasure process for erasing the target information therein.

  According to the embodiment of the present invention, there is provided an information leakage prevention technique capable of preventing information from being leaked by taking out a mobile terminal carried by an operator in an area.

The lineblock diagram showing the information leakage prevention system of a 1st embodiment. The block diagram which shows the information leakage prevention system of 1st Embodiment. The flowchart which shows the positional infomation transmission process of 1st Embodiment. The flowchart which shows the information leakage prevention process of 1st Embodiment. The block diagram which shows the information leakage prevention system of 2nd Embodiment. 9 is a flowchart showing buffer erasure processing according to the second embodiment. The flowchart which shows the work assistance information display process of 2nd Embodiment. The flowchart which shows the information leakage prevention process of 2nd Embodiment. The flowchart which shows the information leakage prevention process of 3rd Embodiment. The block diagram which shows the information leakage prevention system of 4th Embodiment.

(First embodiment)
Hereinafter, this embodiment is described based on an accompanying drawing. First, the information leakage prevention system of 1st Embodiment is demonstrated using FIGS. 1-4. The code | symbol 1 of FIG. 1 is a portable terminal which an operator has. These portable terminals 1 are used to provide each worker with work support information for supporting work when performing maintenance work on various devices provided in a nuclear power plant or the like.

  The portable terminal 1 of this embodiment illustrates a tablet type terminal. The mobile terminal 1 may be other movable information terminals such as a wearable terminal, a smartphone, a mobile phone, a notebook computer, and a small personal computer. Further, not only the same type of mobile terminal 1 but also various types of mobile terminals 1 may be used.

  In the present embodiment, the use of the portable terminal 1 for maintenance work of a nuclear power plant (nuclear power plant) is exemplified, but the portable terminal 1 is used for maintenance work of other plants such as a thermal power plant, a hydroelectric power plant, and a factory. May be used.

  As shown in FIG. 1, the information leakage prevention system of the present embodiment includes a plurality of portable terminals 1, a repeater 2 that receives radio waves transmitted from these portable terminals 1, and the repeater 2. And a management device 3 that manages the mobile terminal 1. In the present embodiment, a simplified configuration is used to help understanding, but devices other than these devices may be included. In addition, a configuration in which a plurality of repeaters 2 and management devices 3 are provided may be employed. Further, the mobile terminals 1 can communicate with each other wirelessly.

  Each portable terminal 1 and the repeater 2 are connected by wireless communication, and the repeater 2 and the management device 3 are connected by wireless communication. The repeater 2 is installed in the work area A or in the vicinity of the work area A. In addition, each mobile terminal 1 in the work area A performs wireless communication with the management device 3 via the repeater 2 at predetermined time intervals. The range in which the repeater 2 can perform wireless communication extends to the vicinity of the work area A. Therefore, the repeater 2 can communicate with the mobile terminal 1 located at a position away from the work area A by a predetermined range. In wireless communication, data to be transmitted / received, commands and others are encrypted.

  Note that the mobile terminal 1 and the management apparatus 3 have hardware resources such as a processor, and are configured by a computer that executes information processing using software by executing various programs. The mobile terminal 1 also includes a minimum network function for connecting to the management apparatus 3 (server), an information display function, and a GUI (Graphical User Interface) for an operator to input and output. Moreover, each part which comprises the portable terminal 1 is comprised as a digital circuit. In addition, each part which comprises the portable terminal 1 may be comprised with an analog circuit, FPGA (field-programmable gate array) etc. besides a digital circuit.

  In the present embodiment, a work area A where an operator works is set in advance. The work area A includes a plurality of work places, and the worker moves to each work place and works. Various devices are installed in the work area A. Information indicating the installation status of these devices and the operation status of the devices is a target of confidentiality. In addition, work support information such as map data in the work area A is transferred from the management device 3 to the portable terminal 1 through the repeater 2. Such work support information is also subject to confidentiality. When the map data in the work area A is displayed on the display unit 14 shown in FIG. 2 described later, the current position of the portable terminal 1 is shown on the map data.

  A predetermined outdoor range is set in the work area A of the present embodiment. 1 illustrates that one work area A is provided, a plurality of work areas A may be provided. Further, a part of one work area A and a part of another work area A may be set to overlap each other. A predetermined indoor range may be used as the work area A. Further, when indoor is set as the work area A, it may be set for each room of the building.

  In addition, the worker who has the mobile terminal 1 can move freely in the work area A. When a plurality of work areas A are set, each work area A may be freely moved, or the worker's action may be restricted for each work area A.

  As shown in FIG. 2, the mobile terminal 1 includes a CPU 10, a ROM 11, and a RAM 12. Furthermore, the portable terminal 1 includes a camera 13 that can capture a still image or a moving image, and a display unit 14 that can display various information.

  Note that the ROM 11 is a memory that can only read stored data, and is configured by a nonvolatile memory that can retain stored contents even when power supply is interrupted. The RAM 12 is a memory that can access stored data in any order, and is composed of a volatile memory that cannot retain the stored contents when the supply of power is interrupted.

  Note that the camera 13 incorporated in the portable terminal 1 is composed of a CCD, a CMOS, or the like. Moreover, you may use the camera 13 which can image infrared rays and a radiation according to a field condition. The display unit 14 includes a liquid crystal display, a plasma display, an organic EL display, a projector, and the like.

  Further, the mobile terminal 1 includes a memory card 15 that is not removable from the main body of the mobile terminal 1. The memory card 15 includes a nonvolatile memory (nonvolatile storage unit) as a storage unit. That is, the memory card 15 is a storage unit that can retain the stored contents even when the power supply is interrupted. In this memory card 15, data such as image data (image information) acquired by the camera 13, input data such as numerical values input by the worker to the portable terminal 1A, data such as work support information transmitted from the management device 3, That is, the acquisition data (target information) acquired in the work area A by the mobile terminal 1A is stored.

  In the present embodiment, the memory card 15 is illustrated as a storage unit that stores acquired data such as image data, input data, and work support information, but the storage unit may be configured by other devices. For example, the storage unit may be configured by a device such as an EEPROM, a flash ROM, or a hard disk as a nonvolatile memory.

  In this embodiment, the memory card 15 is not removable from the main body of the mobile terminal 1, but the memory card 15 may be removable. In that case, the information stored in the memory card 15 is stored in an encrypted state. The encrypted information can be decrypted only by the corresponding portable terminal 1. That is, even if the memory card 15 is detached from the portable terminal 1 and connected to another personal computer or the like, the stored information cannot be read. Note that when an operation for removing the memory card 15 is performed, for example, when an operation for unmounting the memory card 15 is performed, the information stored in the memory card 15 may be forcibly deleted.

  The mobile terminal 1 includes a wireless communication unit 16 for performing wireless communication with the repeater 2. In addition, the mobile terminal 1 includes a measurement unit 17 that measures the distance and direction that the mobile terminal 1 has moved. The measurement unit 17 includes an acceleration sensor and a gyroscope (orientation sensor) as a sensor that detects the movement distance and movement direction of the mobile terminal 1. Or you may detect the moving distance and moving direction of the portable terminal 1 using an image sensor. In addition, the mobile terminal 1 includes a time measuring unit 18 that measures time. Note that the timer unit 18 is composed of an RTC (real-time clock) or the like. In wireless communication, data such as image data to be transmitted / received, commands and others are encrypted.

  In addition, the mobile terminal 1 includes an input unit 19 that can be operated and input by an operator in order to receive various types of information and control instructions. The input unit 19 is a touch panel device integrated with the screen of the display unit 14. The operator can perform various input operations by touching the screen of the display unit 14. The input unit 19 may be a device such as a keyboard or a mouse, an input unit that can perform voice recognition, or an input unit that can perform image recognition including gesture recognition.

  The CPU 10 also includes a main processing unit 20 that performs various types of information processing related to the control of the mobile terminal 1, an information leakage prevention unit 21 for erasing various types of information stored in the memory card 15, and a position received from the management device 3. A position specifying unit 22 for specifying the current position of the mobile terminal 1 based on the information; a position correcting unit 23 for correcting the current position of the mobile terminal 1 based on the moving distance and the moving direction measured by the measuring unit 17; . In the present embodiment, the CPU 10 including the information leakage prevention unit 21 serves as a storage erasure processing unit that executes storage information processing described later.

  The information leakage prevention unit 21 according to the present embodiment acquires image data, input data, work support information, and the like stored in the memory card 15 when the portable terminal 1 possessed by the worker is taken out in the work area A. Control to erase data. Therefore, it is possible to prevent the acquired data from being taken out of the work area A, that is, the target information that is the target of confidentiality from being leaked.

  As shown in FIG. 2, the repeater 2 is transmitted from the control unit 30 that performs various information processing related to control, the wireless communication unit 31 that performs wireless communication with the mobile terminal 1 and the management device 3, and the mobile terminal 1. Terminal direction detection unit 32 that can detect the direction in which the mobile terminal 1 is located based on the radio wave, and terminal distance detection that can detect the distance to the mobile terminal 1 based on the radio wave transmitted from the mobile terminal 1 Unit 33.

  The antenna included in the wireless communication unit 31 includes a plurality of antennas, an antenna array arranged in a lattice shape, and the like. By receiving the radio wave transmitted from the portable terminal 1 with such an antenna unit and performing processing with the terminal direction detection unit 32, the reception intensity and propagation direction can be specified. That is, the terminal direction detection unit 32 can detect the direction in which the portable terminal 1 exists with the repeater 2 as a base point.

  Further, the terminal distance detection unit 33 is based on the difference between the time when the radio communication unit 31 receives the radio wave (pulse signal) of the mobile terminal 1 and the time when the radio wave is transmitted from the mobile terminal 1. The distance from 2 to the portable terminal 1 can be obtained. For example, the propagation distance L (= t × v) [m] can be obtained from the propagation time t [sec] and the propagation velocity v [m / sec] of the radio wave transmitted from the mobile terminal 1.

  The terminal direction detection unit 32 and the terminal distance detection unit 33 have an electronic circuit or software that specifies the transmission position of the radio wave from the reception direction of the radio wave transmitted from the mobile terminal 1. In addition, the repeater 2 transmits the detection value detected by the terminal direction detection unit 32 and the terminal distance detection unit 33 to the management device 3. Further, since each mobile terminal 1 performs wireless communication with the repeater 2 at predetermined time intervals, a detection value indicating the position of each mobile terminal 1 is transmitted to the management device 3 at predetermined time intervals. . In wireless communication, data such as detection values to be transmitted and received, commands, and others are encrypted.

  In the present embodiment, the position of the mobile terminal 1 is detected using one repeater 2, but a plurality of repeaters 2 corresponding to one work area A are provided. You may make it detect the position of the portable terminal 1 using the repeater 2. FIG.

  The repeater 2 of the present embodiment uses an identifier such as an SSID (Service Set Identifier), ESSID (Extended Service Set Identifier) or BSSID (Basic Service Set Identifier), a fixed identifier, or electronic authentication. The mobile terminals 1 that can communicate can be restricted.

  As shown in FIG. 2, the management device 3 includes a control unit 40 that performs various types of information processing related to control, a display unit 41 that can display various types of information, and an input unit 42 that can be operated and input by an administrator. A wireless communication unit 43 for performing wireless communication with the repeater 2, a terminal position specifying unit 44 for specifying the position of the portable terminal 1 based on the detection value transmitted from the repeater 2, and the portable terminal 1 A work support processing unit 45 that performs processing for transmitting work support information and the like.

  When the work support processing unit 45 receives a work support request transmitted from the mobile terminal 1, the work support processing unit 45 provides necessary work support information to the worker who owns the mobile terminal 1. For example, work support information is related to map data in work area A, documents related to plant maintenance and operation, manuals, instructions, worker positions, work schedules, and work places. Information and the like are included in the data file 45A.

  Further, instead of transmitting the data file 45A including the work support information, only image data for displaying the work support information may be transmitted. In this way, the volume of data transferred from the management device 3 to the portable terminal 1 can be reduced, and the transfer time is reduced. Further, since the data file 45A itself including the work support information is not stored in the mobile terminal 1, it is possible to prevent the data file 45A from being leaked.

  The terminal position specifying unit 44 specifies the position of the mobile terminal 1 based on the detection value transmitted from the repeater 2, and generates position information indicating the position of the mobile terminal 1. That is, the terminal position specifying unit 44 is a position information generating unit. And the wireless communication part 43 of the management apparatus 3 transmits this positional information, and the portable terminal 1 corresponding to this positional information receives positional information via the repeater 2. FIG. That is, the wireless communication unit 43 of the management device 3 is a position information transmission unit. The wireless communication unit 16 of the mobile terminal 1 that receives the position information is a position information receiving unit.

  In the mobile terminal 1 that has received the position information from the management device 3, the position specifying unit 22 specifies the current position based on the position information. The position specifying unit 22 includes an electronic circuit or software that specifies the position of the mobile terminal 1. Then, the position correcting unit 23 obtains the measured value measured by the measuring unit 17 and the distance and direction that the mobile terminal 1 has moved. Further, the position correcting unit 23 corrects the position information by adding the distance and direction of movement of the mobile terminal 1 to the position information after receiving the position information from the management device 3 based on the measurement value. Then, based on the position information corrected by the position correction unit 23, the current position of the mobile terminal 1 is specified again. In this way, the position of the mobile terminal 1 can be accurately specified even when the reception of the position information from the management device 3 is interrupted.

  For example, if an attempt is made to specify the position of the mobile terminal 1 based only on the measurement value measured by the measurement unit 17, an error in the measurement value of the measurement unit 17 is accumulated. The position may be significantly different from the actual current position. In the present embodiment, accurate position information is transmitted from the management device 3 at regular time intervals, so that an error in measurement values of the measurement unit 17 is not accumulated, and an accurate current position is always specified. Can do. In this way, it is possible to prevent the mobile terminal 1 from erroneously executing the storage erasure process even though the mobile terminal 1 is in the work area A.

  Even when the position information cannot be temporarily received from the management device 3 due to the presence of an obstacle that blocks radio waves, the mobile terminal 1 specifies the current position by the measurement unit 17 and the position correction unit 23. it can. Furthermore, even if a malicious worker puts the mobile terminal 1 in a box or the like that blocks radio waves and interferes with reception of position information, the mobile terminal 1 is currently connected by the measurement unit 17 and the position correction unit 23. The position can be specified. Therefore, even if the portable terminal 1 is taken out of the work area A in a state where the position information cannot be received, the portable terminal 1 can execute the memory erasure process.

  The ROM 11 of the portable terminal 1 stores area information indicating in advance which area is the work area A in the map data. The area information may be included in information transmitted from the management device 3. Further, the information leakage prevention unit 21 compares the position information with the area information indicating the preset work area A, and specifies whether or not the current position of the mobile terminal 1 is in the work area A.

  When the current position of the mobile terminal 1 cannot be specified within the work area A, that is, when the current position specified based on the position information is outside the work area A, various kinds of information stored in the memory card 15 are stored. A memory erasure process for erasing information (target information) is executed. In the present embodiment, since the current position of the mobile terminal 1 can be accurately specified, when the worker goes out of the work area A with the mobile terminal 1, the memory erasure process can be executed immediately. it can.

  In addition, the information leakage prevention unit 21 of the mobile terminal 1 executes the memory erasure process even when the position information is not received for a predetermined time. In the present embodiment, the timer 18 measures the time during which the next position information is not received after the previous position information is received. Then, when the time counted by the time measuring unit 18 is equal to or longer than a predetermined time, a memory erasure process is executed.

  In this way, even if the worker stops taking the portable terminal 1 and takes it out of the work area A, the storage erasure process is executed to erase various information stored in the portable terminal 1. Can do. In addition, since the administrator operates the management device 3 to stop the transmission of the position information, the storage erasure process is executed in the mobile terminal 1, so that the administrator who operates the management device 3 has a plurality of Even if the portable terminal 1 is in the work area A, various information stored in the portable terminal 1 can be erased collectively. If a malicious worker puts the mobile terminal 1 in a box or the like that blocks radio waves and interferes with reception of position information, the memory erasure process is performed when a specified time elapses after the radio waves are blocked. Therefore, various information stored in the mobile terminal 1 can be erased.

  In the present embodiment, it is not necessary for the administrator to check each portable terminal 1 taken out from the work area A, or for the operator to perform an operation of erasing the memory, and the work area A can be managed efficiently. It can be carried out. Therefore, the labor and burden of the operator is reduced, and the maintenance work of the plant can be efficiently performed while improving the security.

  Next, position information transmission processing executed by the management apparatus 3 will be described with reference to FIG. In the description of each step in the flowchart, for example, a portion described as “Step S11” is abbreviated as “S11”.

  First, the control unit 40 of the management device 3 determines whether or not communication with the mobile terminal 1 has been performed via the repeater 2 (S11). Here, when communication with the portable terminal 1 is not performed, the position information transmission process is terminated. On the other hand, when communication is performed with the mobile terminal 1, the terminal position specifying unit 44 determines the position of the mobile terminal 1 based on the detected value of the reception direction and the reception distance of the mobile terminal 1 transmitted from the repeater 2. The terminal position specifying unit 44 generates position information indicating the position of the portable terminal 1 (S12: position information generation step). Next, the wireless communication unit 43 transmits the position information to the repeater 2 (S13: position information transmission step). The position information is transmitted to the mobile terminal 1 via the repeater 2. Then, the position information transmission process ends.

  Next, information leakage prevention processing executed by the mobile terminal 1 will be described with reference to FIG. The mobile terminal 1 wirelessly communicates with the management device 3 via the repeater 2 at predetermined intervals, and receives location information from the management device 3 (location information reception step). Further, acquired data such as image data (image information) acquired by the camera 13, input data input by the worker to the portable terminal 1 </ b> A, work support information transmitted from the management device 3, and the like are stored in the memory card 15. (Memory step).

  First, the information leakage prevention unit 21 of the mobile terminal 1 determines whether or not the wireless communication unit 16 has received the position information transmitted from the management device 3 (S21). If no position information has been received, the process proceeds to S23 described later. On the other hand, if position information has been received, the process proceeds to S22.

  In S <b> 22, the position specifying unit 22 specifies the current position of the mobile terminal 1 based on the position information received from the management device 3. Then, the process proceeds to S25 described later.

  In S23, the information leakage prevention unit 21 refers to the time measuring unit 18, and after receiving the previous position information, whether or not the state where the next position information is not received has continued for a predetermined time or more, that is, the previous position information. It is determined whether or not a specified time has elapsed since the reception of. If the specified time has elapsed, the process proceeds to S26 described later. On the other hand, if the specified time has not elapsed, the process proceeds to S24.

  In S <b> 24, the position correction unit 23 acquires a measurement value indicating the distance and direction in which the mobile terminal 1 has moved from the measurement unit 17, and after receiving the previous position information, the position correction unit 23 indicates the distance and direction in which the mobile terminal 1 has moved. In addition, the position information is corrected. Then, the process proceeds to S25.

  In S25, the information leakage prevention unit 21 compares the position information with the area information indicating the preset work area A, and determines whether or not the current position of the mobile terminal 1 is within the work area A. Here, when the current position of the mobile terminal 1 is within the work area A, the information leakage prevention process is terminated. On the other hand, if the current position of the mobile terminal 1 is not in the work area A, the process proceeds to S26.

  In S26, when the current position of the mobile terminal 1 is not in the work area A in S25, or when the specified time has elapsed after receiving the previous position information in S23, the information leakage prevention unit 21 determines whether the memory card 15 A memory erasure process for erasing various information (object information) stored in the memory is executed (memory erasure step). Then, after the information is erased, the information leakage prevention process is terminated.

  In this way, the management device 3 executes the location information transmission process, and the mobile terminal 1 executes the information leakage prevention process, so that the mobile terminal 1 specifies the current location based on the location information specified by the management device 3. can do. In addition, the fact that the mobile terminal 1 can be specified in the work area A based on the position information is a condition for maintaining storage of various types of information (target information). Therefore, when the management device 3 stops the execution of the location information transmission process, the location information is not transmitted, and the memory erasure processing is executed in the mobile terminal 1, so that the administrator who operates the management device 3 Even if a plurality of mobile terminals 1 are in the work area A, various information stored in the mobile terminals 1 can be erased collectively.

  As described above, when the position of the mobile terminal 1 is not included in the work area A, that is, when the mobile terminal 1 is outside the work area A and when the position information cannot be received, the memory erasure process is executed and the target Information can be erased. Therefore, it is possible to prevent information from leaking when the portable terminal 1 carried by the worker in the work area A is taken out.

  Note that the mobile terminal 1 according to the first embodiment is in a standby state until position information is received from the management device 3 at the time of startup (when the power is turned on). And based on the positional information received from the management apparatus 3, when it determines with the position of the portable terminal 1 not being included in the work area A, or the state without receiving positional information continued over the regulation time. In this case, a storage erasure process for erasing various information (target information) stored in the memory card 15 is executed.

(Second Embodiment)
Next, an information leakage prevention system according to the second embodiment will be described with reference to FIGS. In addition, about the component same as the component shown by embodiment mentioned above, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  The portable terminal 1A of the second embodiment includes a minimum network function for connecting to the management apparatus 3A (server), an information display function, and a GUI (Graphical User Interface) for an operator to input and output. This portable terminal 1A is not provided with a device such as a memory card or a hard disk constituted by a nonvolatile memory that holds the acquired information. That is, the mobile terminal 1A is configured as a thin client terminal. And it is the system which made the portable terminal 1A perform the required minimum process and concentrated the process on the management apparatus 3A side.

  In addition, when using the existing product provided with the device comprised with a non-volatile memory as 1 A of portable terminals, while removing this device and working with the modification which removed the part for attaching or detaching a device, work Distribute

  Unlike the portable terminal 1 according to the first embodiment, the portable terminal 1A according to the second embodiment does not include the memory card 15. In the mobile terminal 1A of the second embodiment, image data (image information) acquired by the camera 13, input data such as numerical values input by the worker to the mobile terminal 1A, work support information transmitted from the management device 3A, and the like That is, the acquired data (target information) acquired in the work area A by the portable terminal 1A is stored in the RAM 12 (volatile storage unit).

  In the second embodiment, the work support information can be displayed only when the mobile terminal 1A is in the work area A. That is, when the portable terminal 1A is taken out of the work area A, the work support information cannot be displayed. Further, the work support information stored in the RAM 12 is deleted when a predetermined time has elapsed after being received from the management device 3A. Or you may delete, when 1 A of portable terminals display work assistance information, and predetermined time passes.

  Further, when shooting is performed with the camera 13 in the work area A, the image data is temporarily stored in the buffer area of the RAM 12. This image data is immediately transmitted to the management apparatus 3A. The input data is temporarily stored in the buffer area of the RAM 12 when the operator inputs it to the mobile terminal 1. And it transmits with respect to 3 A of management apparatuses after input. Note that the camera 13 that acquires image data (target information) in the work area A and the input unit 19 to which input data and the like are input are target information acquisition units. And the wireless communication part 16 which portable terminal 1A transmits these acquisition data (target information) to the management apparatus 3A via the repeater 2 becomes a target information transmission part.

  The management device 3A includes a received data storage unit 46 that stores received data such as image data and input data received from the mobile terminal 1A. The CPU 10 of the mobile terminal 1A includes a post-transmission erasure unit 24 that erases the transmitted data (buffer data) from the buffer area of the RAM 12 after transmitting the data to the management device 3A. In wireless communication, data such as image data to be transmitted / received, commands and others are encrypted.

  Also, the received data storage unit 46 of the management device 3A is a semiconductor storage device such as a semiconductor memory that is a nonvolatile memory, an optical storage device such as a CD, DVD, or BD, or a magnetic device such as a hard disk or a magnetic tape. It consists of a storage device of the type. Data stored in such a storage device is encrypted using a secret key encryption method or a public key encryption method. Therefore, information leakage can be prevented.

  In the second embodiment, since the acquired data (target information) acquired in the work area A is not constantly stored in the mobile terminal 1A (RAM 12), information leakage can be prevented. And the data acquired with 1 A of portable terminals can be memorize | stored and managed collectively by 3 A of management apparatuses.

  Note that when the worker who has the portable terminal 1A goes out of the work area A and the buffer data remains in the buffer area of the RAM 12 of the portable terminal 1A, the information leakage prevention unit 21 erases the buffer data. Perform the process. Since the buffer data is erased in this way, information leakage can be prevented. Further, the data to be deleted by the information leakage prevention unit 21 may delete not only image data and input data but also work support information transmitted from the management device 3A. In this way, it is possible to prevent leakage of image data, input data, work support information, etc. acquired in the work area A.

  The information leakage prevention unit 21 deletes only the buffer data from the data stored in the RAM 12, and does not delete other data, for example, data related to the OS and various software necessary for the operation of the mobile terminal 1A. I have to. Therefore, even if the portable terminal 1A is taken out of the work area A, the operation of the portable terminal 1A is continued. Further, outside the work area A, a warning prompting the worker to return to the work area A may be displayed on the display unit 14 of the mobile terminal 1A.

  Next, buffer erasure processing executed by the mobile terminal 1A will be described with reference to FIG. When image data, input data, or the like is acquired by the portable terminal 1A, the acquired data is temporarily stored in the buffer area of the RAM 12. First, the information leakage prevention unit 21 of the mobile terminal 1A determines whether there is acquired data in the buffer area of the RAM 12 (S31).

  Here, if there is no acquired data in the buffer area of the RAM 12, the buffer erasure process is terminated. On the other hand, if there is acquired data in the buffer area of the RAM 12, an acquired data transmission process for transmitting the acquired data to the management device 3A is executed (S32). For example, in the case of acquired data with a large capacity, it may take several seconds to transmit it. Note that the CPU 10 of the mobile terminal 1A can execute other processes in parallel even when the information leakage prevention unit 21 is executing the buffer erasure process.

  Next, the information leakage prevention unit 21 determines whether transmission of acquired data is completed (S33). If the acquisition data transmission has not been completed, the process returns to the acquisition data transmission process of S32. On the other hand, when the transmission of the acquired data is completed, the post-transmission erasure unit 24 executes a buffer data erasure process (memory erasure process) for erasing the acquired data stored in the buffer area of the RAM 12 (S34). Then, the buffer erasure process ends.

  Next, work support information display processing executed by the mobile terminal 1A will be described with reference to FIG. When the portable terminal 1A receives the work support information from the management device 3A, the work support information is stored in the buffer area of the RAM 12. First, the information leakage prevention unit 21 of the portable terminal 1A determines whether or not work support information has been received, that is, whether or not there is work support information in the buffer area of the RAM 12 (S41). Here, when the work support information is not received, the work support information display process is terminated. On the other hand, when the work support information is received, the process proceeds to S42.

  In S42, the information leakage prevention unit 21 compares the position information with the area information indicating the preset work area A, and determines whether or not the current position of the mobile terminal 1A is in the work area A. Here, when the current position of the portable terminal 1A is in the work area A, the work support information is displayed on the display unit 14 (S43). Then, the work support information display process ends. On the other hand, if the current position of the portable terminal 1A is not in the work area A, an error message is displayed on the display unit 14 (S44). Then, the work support information display process ends.

  The error message may be any message that alerts the operator, for example, “work support information cannot be displayed because it is outside work area A”. Furthermore, work support information may be displayed on the display unit 14 when the current position of the mobile terminal 1A returns to the work area A.

  Next, information leakage prevention processing executed by the mobile terminal 1A will be described with reference to FIG. The information leakage prevention process of the second embodiment differs from the information leakage prevention process of the first embodiment (see FIG. 4) only in steps S27 and S28, and the steps from S21 to S25 are the same as those of the first embodiment. This is the same step as the information leakage prevention process.

  In the second embodiment, if the current position of the portable terminal 1A is not in the work area A in S25, or if the specified time has elapsed after receiving the previous position information in S23, the process proceeds to S27. In S27, the information leakage prevention unit 21 determines whether or not there is buffer data in the buffer area of the RAM 12, that is, acquisition data such as image data, input data, and work support information. Here, if there is no buffer data in the buffer area of the RAM 12, the information leakage prevention process is terminated. On the other hand, if there is buffer data in the buffer area of the RAM 12, the information leakage prevention unit 21 executes a storage erasure process for erasing the buffer data stored in the buffer area of the RAM 12 (S28). Then, after erasing the buffer data, the information leakage prevention process is terminated.

(Third embodiment)
Next, the information leakage prevention process of 3rd Embodiment is demonstrated using FIG. Note that the mobile terminal 1A of the third embodiment has the same configuration as the mobile terminal 1A of the second embodiment. Also, the information leakage prevention process of the third embodiment differs from the information leakage prevention process (see FIG. 4) of the first embodiment only in the step S29, and the steps from S21 to S25 are the information of the first embodiment. This is the same step as the leakage prevention process.

  In the second embodiment, the process proceeds to S29 when the current position of the portable terminal 1A is not in the work area A in S25, or when the specified time has elapsed after receiving the previous position information in S23. In S29, the information leakage prevention unit 21 executes a shutdown process (memory erasure process) for turning off the mobile terminal 1A (S29). As described above, when the portable terminal 1A is shut down and turned off, acquired data such as image data, input data, and work support information stored in the RAM 12 is deleted.

  In this way, when the worker goes out of the work area A, the buffer data (target information) stored in the RAM 12 (storage unit) of the mobile terminal 1A is erased, so that information leakage can be prevented. . In addition, since the mobile terminal 1A is turned off outside the work area A, it is not possible to take a picture with the camera 13 or acquire work support information in the vicinity of the work area A. It can be prevented from being acquired.

  In the portable terminal 1A of the third embodiment, image data, input data, and the like need not be deleted from the buffer area of the RAM 12 after being transmitted to the management device 3A. Even if the buffer area of the RAM 12 remains, the data stored in the RAM 12 can be erased because the mobile terminal 1A is shut down when taken out of the work area A.

(Fourth embodiment)
Next, the information leakage prevention system of 4th Embodiment is demonstrated using FIG. In addition, about the component same as the component shown by embodiment mentioned above, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  The management device 3B according to the fourth embodiment generates a flow line information generating unit 47 that generates a flow line information including a route along which the mobile terminal 1 has moved, and a progress that generates progress information capable of grasping the progress of work at the work place. The information generation part 48, the work time calculation part 49 which calculates work time required in a predetermined work place, and the worker management database 50 for managing a worker are provided. Except for these configurations, the configuration is the same as that of the first embodiment.

  Note that the flow line information generation unit 47 continuously acquires the position information of each mobile terminal 1, so that the flow line information including the route traveled by the mobile terminal 1, that is, the worker who owns the mobile terminal 1. The flow line information (movement history) can be acquired. Then, the flow line information is displayed on the display unit 41. In this way, since the administrator can monitor the flow line of the worker using the management device 3B, it becomes easy to find a worker who moves suspiciously in the work area A. Further, not only the current flow line of the worker but also the flow line of the worker can be displayed retroactively.

  In addition, when there is an operator who stays in a specific place for a long time, the fact may be notified. Moreover, it is greatly different from the worker who often leaves the work place, the worker who takes a picture using the camera 13 outside the predetermined range, the worker who performs the input operation unrelated to the work, and other workers. If there is an operator who moves differently, the fact may be notified. Thus, in this embodiment, since the behavior of each worker can be managed, the administrator can manage the safety, health, number of workers, work efficiency, and suspicious behavior of the worker.

  In addition, the progress information generation unit 48 identifies the time when each portable terminal 1 existed at each work place in the work area A based on the flow line information generated by the flow line information generation unit 47, and Progress information that can grasp the progress of work is generated. Then, the progress information is displayed on the display unit 41. In this way, the administrator can grasp the progress of the work at the work place using the management device 3B.

  For example, the progress information generation unit 48 acquires the past and current positions of the worker who has the mobile terminal 1. Then, before starting the work, the current work place and the staying time at this work place are obtained. Furthermore, it collates with the plan value of the work plan. For example, the number of work places where work has been completed and the work time up to the present are obtained. Then, the work progress is quantitatively expressed as a percentage by calculating (number of finished work places) / (total number of work places) × 100, (work time up to now) / (plan value of work time) × 100. And you can ask online.

  Further, when a plurality of workers perform work, even if the work is the same, the work time required for the work may differ depending on the years of practical experience and skill of each worker. Therefore, the management device 3B of the fourth embodiment collects worker information including the number of years of practical experience of the worker and the progress information generated by the progress information generation unit 48 in the worker management database 50.

  Then, based on the information collected by the worker management database 50, the work time calculation unit 49 calculates the work time necessary for each worker before starting work at the predetermined work place. To do. The work time calculation unit 49 is an electronic circuit or software that obtains a relationship between years of practical experience and each work time.

  The work time calculation unit 49 creates a standard work time in consideration of the years of practical experience of each worker. For example, there is a method in which workers are classified according to years of practical experience, and the average working time of workers corresponding to each classification is used as the working time of workers of that classification. As a result, when an operator is determined at each work place, if the work is sequentially performed by all the workers, the work time of each worker is added to obtain the standard work time. In addition, if the work is performed in parallel by all the workers, the longest work time among the workers is set as the standard work time. This method is an example, and the standard work time may be created using other methods. In this way, the administrator can make a work plan suitable for the worker using the management device 3B. In addition, it is possible to make a construction plan with high work time accuracy at each work place.

  Although the information leakage prevention system according to the present embodiment has been described based on the first to fourth embodiments, the configuration applied in any one of the embodiments may be applied to other embodiments, You may combine the structure applied in each embodiment. For example, when the portable terminal is taken out of the work area, the process of erasing the storage content of the nonvolatile storage unit of the first embodiment and the process of erasing the storage content of the volatile storage unit of the second embodiment All the processes including the process of turning off the power of the portable terminal according to the third embodiment may be executed.

  Note that in the determination using the determination value such as the specified time of the present embodiment, the determination of “whether or not it is equal to or greater than the determination value” is performed, but this determination is also performed in the determination of “whether or not the determination value is exceeded”. The determination may be “whether it is less than or equal to the determination value”, or may be determination “whether it is less than the determination value”.

  In the present embodiment, it is desired to determine whether or not the current position of the mobile terminal 1 is within the work area A in S25 of the information leakage prevention process, but the current position of the mobile terminal 1 is outside the work area A. It may be determined whether or not it is in the range.

  Further, a predetermined range in the vicinity of the work area A is set as a determination hold area, and even if the portable terminal 1 is taken out of the work area A, the storage erase process is not immediately executed, and the area is outside the determination hold area. When the portable terminal 1 is taken out, the memory erasure process may be executed.

  In the present embodiment, the position information is corrected based on the moving distance and moving direction of the mobile terminal 1 measured by the measuring unit 17, but the position information is calculated based on the value measured by a satellite positioning system or the like. You may correct it.

  In the present embodiment, the position of the mobile terminal 1 is specified based on the terminal direction detection unit 32 and the terminal distance detection unit 33 included in the repeater 2 that relays transmission / reception of information between the mobile terminal 1 and the management device 3. However, the wireless device that transmits and receives information and the wireless device that specifies the position of the mobile terminal 1 may be different devices.

  Moreover, when specifying the position of the portable terminal 1 with the some repeater 2, what is necessary is just to provide either one of the terminal direction detection part 32 and the terminal distance detection part 33. FIG. For example, if the direction of the mobile terminal 1 can be specified by the terminal direction detection unit 32 of the two repeaters 2, the position of the mobile terminal 1 can be specified based on the distance between the repeaters 2 and the detected direction. Moreover, if the distance of the portable terminal 1 can be specified by the terminal distance detection unit 33 of the two repeaters 2, the position of the portable terminal 1 can be specified based on the distance between the repeaters 2 and the detected distance.

  In the present embodiment, the mobile terminal 1 communicates with the management apparatus 3 at regular intervals, but when an operator uses the mobile terminal 1 to request the management apparatus 3 to provide information. Only the configuration in which the mobile terminal 1 and the management device 3 communicate with each other may be used.

  The position information of this embodiment is coordinate information indicating the position on the map where the mobile terminal 1 is present. Note that the position information is not limited to the coordinate information, but may be specific information indicating whether the mobile terminal 1 is in the work area A, for example, or the mobile terminal 1 holds the storage of the target information. It may be permission information indicating whether to permit or not.

  In the present embodiment, image data acquired by the camera 13, input data input by the input unit 19, and acquired data such as work support information transmitted from the management device 3 are subject information to be kept confidential. However, information other than these may be target information. For example, input information such as numerical values measured in the work area A by a measuring instrument connected to the mobile terminal 1 may be target information, or information received from another mobile terminal 1 may be target information. .

  According to the embodiment described above, when the mobile terminal cannot be identified as being in the work area based on the position information or the reception state thereof, the memory erasure process for erasing the target information stored in the storage unit is executed. By doing so, it is possible to prevent information from being leaked by taking out the portable terminal carried by the worker in the work area.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, changes, and combinations can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Portable terminal, 2 ... Repeater, 3 ... Management apparatus, 13 ... Camera, 14 ... Display part, 15 ... Memory card, 16 ... Wireless communication part, 17 ... Measuring part, 18 ... Time measuring part, 19 ... Input part, DESCRIPTION OF SYMBOLS 20 ... Main process part, 21 ... Information leakage prevention part, 22 ... Position specification part, 23 ... Position correction part, 24 ... Erasing part after transmission, 30 ... Control part, 31 ... Wireless communication part, 32 ... Terminal direction detection part, 33 ... Terminal distance detection unit, 40 ... Control unit, 41 ... Display unit, 42 ... Input unit, 43 ... Wireless communication unit, 44 ... Terminal position specifying unit, 45 ... Work support processing unit, 46 ... Received data storage unit, 47 ... a flow line information generation unit, 48 ... a progress information generation unit, 49 ... an operation time calculation unit, 50 ... an operator management database.

Claims (14)

An information leakage prevention system comprising a portable terminal carried by an operator in an area and a management device for managing the portable terminal,
The management device
A position information generating unit that generates position information indicating the position of the mobile terminal based on radio waves transmitted from the mobile terminal;
A position information transmitter for transmitting the position information to the mobile terminal;
With
The portable terminal is
A storage unit for storing target information that is a target of information leakage prevention;
A location information receiving unit that receives the location information from the management device;
A storage erasure processing unit for executing a storage erasure process for erasing the target information stored in the storage unit based on the position information or a reception state thereof;
An information leakage prevention system comprising:   The information leakage prevention system according to claim 1, wherein the memory erasure processing unit erases the target information by an information leakage prevention unit when the mobile terminal cannot be identified as being in the area.   The memory erasure processing unit compares the position information with area information indicating the preset area, and executes the memory erasure processing when the position of the mobile terminal is not included in the area. The information leakage prevention system according to claim 1 or 2. The mobile terminal includes a timekeeping unit that times the time during which the position information is not received.
4. The memory erasure processing unit according to claim 1, wherein the memory erasure processing unit executes the memory erasure processing when the time measured by the time measuring unit is equal to or longer than a predetermined time. 5. Information leakage prevention system. The portable terminal is
A measuring unit for measuring the distance and direction the mobile terminal has moved;
A position correction unit that corrects the position information based on the distance and direction the portable terminal has moved after receiving the position information;
An information leakage prevention system according to any one of claims 1 to 4, further comprising: The portable terminal includes a nonvolatile storage unit that is the storage unit and can retain stored contents even when power supply is interrupted,
6. The information leakage prevention system according to claim 1, wherein the storage erasure processing unit executes the storage erasure processing for erasing the target information stored in the nonvolatile storage unit. The portable terminal includes a volatile storage unit that is the storage unit and cannot retain stored contents when power supply is interrupted,
The information leakage prevention system according to any one of claims 1 to 5, wherein the memory erasure processing unit executes the memory erasure processing to turn off the power of the mobile terminal. The portable terminal is
A volatile storage unit that is not capable of holding stored content when the supply of power is interrupted in the storage unit;
A target information acquisition unit for acquiring the target information in the area;
A target information transmission unit for transmitting the acquired target information to the management device;
A post-transmission erasure unit that erases the target information after transmission from the volatile storage unit;
With
6. The storage erasure processing unit executes the storage erasure processing for erasing the target information when the untransmitted target information is stored in the volatile storage unit. 1. The information leakage prevention system according to item 1.   9. The information according to claim 1, wherein the target information includes at least one of image information captured by a camera incorporated in the mobile terminal and work support information transmitted from the management device. 1. The information leakage prevention system according to item 1.   The said management apparatus is provided with the flow line information production | generation part which produces | generates the flow line information containing the path | route which the said portable terminal moved at least based on the said positional information. Information leakage prevention system.   The management device identifies progress time based on the flow line information and identifies the time when the portable terminal is present at the work place in the area, and generates progress information that can grasp the progress of work at the work place. The information leakage prevention system according to claim 10, further comprising a generation unit. The management device
A database that collects worker information including at least years of practical experience of the worker and the progress information;
Before starting work at a predetermined work place, a work time calculation unit for calculating work time required at this work place based on the information in the database;
The information leakage prevention system according to claim 11. An information leakage prevention method using a portable terminal carried by an operator in an area and a management device that manages the portable terminal,
A position information generating step in which the management device generates position information indicating the position of the mobile terminal based on radio waves transmitted from the mobile terminal;
A location information transmission step in which the management device transmits the location information to the mobile terminal;
A storage step in which the portable terminal stores target information that is a target of information leakage prevention;
A location information receiving step in which the mobile terminal receives the location information from the management device;
A storage erasure step for executing a memory erasure process for erasing the target information being memorized based on the position information or its reception state;
An information leakage prevention method comprising: A mobile terminal owned by an operator in the area,
A storage unit for storing target information that is a target of information leakage prevention;
A location information receiving unit that receives location information from the management device;
A storage erasure processing unit for executing a storage erasure process for erasing the target information stored in the storage unit based on the position information or a reception state thereof;
A portable terminal comprising:

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