Patent Publication Number: US-2016224585-A1

Title: Controller, worker terminal, information deletion method, and program

Description:
TECHNICAL FIELD 
     The present disclosure relates to a controller, a worker terminal, an information deletion method, and a program. 
     BACKGROUND ART 
     Recently, home network systems that have various electrical devices connected to one another based on a predetermined communication standard are becoming more prevalent in ordinary homes. According to such home network systems, electrical devices, such as an air conditioner, a lighting device, a rice cooker, an IH cooking device, and an air dehumidifier, are communicably connected with a controller, and the electrical devices are manageable (for example, integration of amount of power consumption, and control in accordance with schedule) via the controller. 
     According to such home network systems, at the time of, for example, an initial installation work, a worker actually activates an electrical device, and carries out an adjustment that includes a set-up, and a general operation check. When a check result does not show any problem, the worker hands over the system to a user after deletion (including initialization) of information like measurement data from the controller. That is, because of an activation prior to the hand-over, an amount of power consumption, and the like of an electrical device is measured, and such measurement data (for example, an integrated power amount) is stored in the controller, and thus the worker initializes such information. In addition, after the system is handed over, there are cases in which the user makes a replace purchase of the electrical device. At the time of maintenance work for such electrical device replacement, the worker deletes information from the controller after the installation of the new replacement electrical device and an operation check thereof. 
     For example, Patent Literature 1 discloses, as a conventional technology to delete information while performing maintenance work, and the like, a power management system that facilitates a deletion of information. According to this power management system, when an operation to change a user is given, necessary information for the maintenance of equipment (for example, a record of an amount of power generation and a total operation time) is left for the next user who will take over the system, and only information relating to the former user (for example, an amount of power consumption and an amount of purchase and sale power) is deleted. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: Unexamined Japanese Patent Application Kokai Publication No. 2013-045376 
     SUMMARY OF INVENTION 
     Technical Problem 
     According to the technology disclosed in Patent Literature 1, since a general user is capable of giving an operation to change the user, information may be deleted against the will of the user. When, for example, incorrect password is entered multiple times, the power management system disclosed in Patent Literature 1 deletes even the information on the current user because of a function that does not allow the current user to review information on the previous user. In addition, at the time of an installation work and of a maintenance work, when the worker should give an operation to change the user prior to the hand-over of the system, if the worker forgets to carry out such an operation, information that should normally be deleted still remains after the hand-over. Hence, the measurement data to be managed may become inaccurate, and personal information, and the like, may be revealed to a third party. 
     The present disclosure is made in view of the aforementioned circumstances, and an objective of the present disclosure is to provide a controller, a worker terminal, an information deletion method, and a program that are capable of appropriately deleting information while enhancing a security. 
     Solution to Problem 
     In order to accomplish the above objective, a controller according to the present disclosure is configured to manage an electrical device installed in a residence, the controller including: 
     a communicator configured to communicate with a worker terminal operated by a worker, or a user terminal operated by a user; 
     an authenticator configured to authenticate the worker terminal to be communicated with the communicator; 
     a command executing processor configured to execute a process in accordance with a command transmitted from the worker terminal authenticated by the authenticator or the user terminal; and 
     a memory configured to store various pieces of information relating to the electrical device, 
     in which: 
     the command executing processor is configured to, only when the command is transmitted from the worker terminal authenticated by the authenticator and is for instructing a deletion of information defined in accordance with a work, delete the instructed information among the pieces of information stored in the memory. 
     Advantageous Effects of Invention 
     According to the present disclosure, information can be appropriately deleted while enhancing security. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram illustrating an example structure of a home network system according to an embodiment of the present disclosure; 
         FIG. 2  is a block diagram illustrating an example structure of a worker terminal; 
         FIG. 3  is a schematic diagram illustrating an example work screen; 
         FIG. 4  is a block diagram illustrating an example structure of a user terminal; 
         FIG. 5  is a block diagram illustrating an example structure of a controller; 
         FIG. 6  is a schematic diagram illustrating example unique information and personal information stored in a memory; 
         FIG. 7  is a schematic diagram illustrating example measurement data stored in the memory; 
         FIG. 8  is a sequence diagram illustrating an example basic sequence between the worker terminal and the controller; 
         FIG. 9  is a sequence diagram illustrating a specific example of the basic sequence; 
         FIG. 10  is a block diagram illustrating an example structure of a worker terminal according to a second embodiment of the present disclosure; 
         FIG. 11  is a schematic diagram illustrating example work procedure information stored in a memory; 
         FIG. 12  is a schematic diagram illustrating example measurement data according to a third embodiment of the present disclosure; and 
         FIG. 13  is a graph for explaining an integrated power amount when an offset value is applied. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments of the present disclosure is explained below. In the following explanation, in order to facilitate understanding, example embodiments in which the present disclosure is applied to a controller, and the like, is explained, but the present disclosure is also applicable to information processing devices, such as various computers, PDAs, and mobile phones. That is, embodiments explained below are merely intended to explain, and are not intended to limit the scope and spirit of the present disclosure. Hence, a person of ordinary skill in the art can adopt an embodiment in which each of or all of components are replaced with equivalents, and such embodiment is also within the scope and spirit of the present disclosure. 
     First Embodiment 
       FIG. 1  is a block diagram illustrating an example structure of a home network system  1  according to a first embodiment of the present disclosure. This home network system  1  is, as an example, a system that manages each electrical device  5  installed in a residence H, and includes a worker terminal  2 , a user terminal  3 , a controller  4 , and the multiple electrical devices  5 . Among those components, the controller  4  and each of the electrical devices  5  are communicably connected with each other via an in-home network  9  (for example, wired or wireless network). In addition, the worker terminal  2  and the controller  4 , and, the user terminal  3  and the controller  4  are also communicably connected with each other via, for example, a wireless LAN. Note that the worker terminal  2  and the user terminal  3  may be also communicably connected to the controller  4  via the in-home network  9 . 
     The worker terminal  2  is, for example, a mobile terminal, such as a tablet terminal or a smartphone, and is utilized by a worker who carries out an installation work of the electrical device  5  and a maintenance work thereof. Note that the installation work is a work carried out before the home network system  1  is handed over to a user, and for example, the worker actually activates the electrical device  5 , and carries out an adjustment including a set-up and a general operation check. Also note that the maintenance work is a work carried out when, for example, the user makes a replacement purchase of the electrical device  5  after the home network system  1  is handed over to such a user, and for example, the worker installs the new replacement electrical device  5  and carries out an operation check thereof. An example structure of the worker terminal  2  utilized at the time of those works is explained below with reference to  FIG. 2  which is a block diagram. As illustrated in the figure, the worker terminal  2  includes a communicator  21 , display unit  22 , input unit  23 , a data memory  24 , and a control unit  25 . 
     The communicator  21  includes, for example, an interface for a wireless LAN connection that conforms to Wi-Fi (registered trademark) standards, and performs data communication with the controller  4  under the control of the control unit  25 . 
     The display unit  22  includes a liquid crystal panel or the like, and displays various screens, and the like under the control of the control unit  25 . More specifically, the display unit  22  displays a work screen  220  illustrated in  FIG. 3 . This work screen  220  is, for example, a screen presented when the worker carries out an installation work of the electrical device  5 , and includes, for example, a dropdown list  221  to select the device, a dropdown list  222  to select a command to be transmitted to the controller  4 , and a button  223  to instruct a transmission of the selected command Note that the details of the command to be transmitted to the controller  4  are explained further below together with the control unit  25  (worker command transmitting processor  252 ). 
     Referring back to  FIG. 2 , the input unit  23  includes a touch panel, a touch pad, and the like, and accepts an operation input made by the user. When, for example, the input unit  23  is a touch panel, an electrostatic capacitance sensor which is a transparent plate component, and which detects a change in electrostatic capacitance is laid over on a liquid crystal display. When this electrostatic capacitance sensor detects a contact (pressing force) to a touchscreen (display screen of liquid crystal display for user) by a fingertip of the user or a dedicated pen, information on such a position (coordinate data) is output to the control unit  25 . The control unit  25  determines the details of the operation given by the user based on the position information. When the user carries out an input operation via the input unit  23 , signals in accordance with the details of the operation are supplied to the control unit  25 . 
     The data memory  24  has a role of a so-called secondary memory device (auxiliary memory device), and includes, for example, a non-volatile readable and writable semiconductor memory like a flash memory. The data memory  24  stores terminal authentication information  241  that is necessary for an authentication of the worker terminal  2 . This terminal authentication information  241  is information indicating that the local device is the “worker terminal” In addition, the data memory  24  stores, for example, a program to be executed by the control unit  25 . 
     The control unit  25  includes a Central Processing Unit (CPU), a Read Only Memory (ROM), a Random Access Memory (RAM), and the like (all unillustrated), and controls each of the above-explained components. The control unit  25  includes, as a functional structure, an authentication requesting processor  251 , a worker command transmitting processor  252 , and a response receiving processor  253 . These functions are realized by the CPU which utilizes the RAM as a work memory, and which executes various programs as needed stored in the ROM and the data memory  24 . 
     The authentication requesting processor  251  requests the controller  4  to authenticate the terminal via the communicator  21 . That is, the authentication requesting processor  251  requests the controller  4  to authenticate the worker terminal  2  so as to permit only the worker (worker terminal  2 ) to transmit worker commands Next, the authentication requesting processor  251  reads the terminal authentication information  241  from the data memory  24 , and transmits the read information to the controller  4 . Note that the details of the authentication of the worker terminal  2  are explained further below together with the controller  4  (control unit  43 ). 
     The worker command transmitting processor  252  transmits worker commands by the worker that instruct the controller  4  to perform necessary operations during the installation work and in the maintenance work. More specifically, when a command is selected via the dropdown list  222 , and the button  223  that instructs a transmission of the command is pressed by the worker in the work screen  220  illustrated in  FIG. 3 , the worker command transmitting processor  252  transmits the corresponding worker command to the controller  4 . 
     During the installation work, for example, the worker command transmitting processor  252  transmits a command to set up the electrical device  5 , a command to check the operation of the electrical device  5 , and a command to delete (initialize) measurement data on the electrical device  5 . Note that because of the activation of the electrical device  5  during the installation work, an amount of power consumption, and the like of the electrical device  5  has already been measured, and the measurement data (for example, integrated power amount) has already been stored in the controller  4  (data memory  42  is explained further below), a command to delete the measurement data is a command to initialize such measurement data. In addition, in the case of the maintenance work, the worker command transmitting processor  252  transmits, for example, a command to set up the new replacement electrical device  5 , a command to check the operation of the electrical device  5 , and a command to delete information unique to the former electrical device, and user&#39;s personal information relating to the former electrical device  5 . Note that those commands are merely examples, and can be changed as needed in accordance with the details of the installation work and those of the maintenance work. 
     The response receiving processor  253  receives a response to be transmitted by the controller  4  and corresponding to the worker command transmitted to the controller  4  by the worker command transmitting processor  252 . For example, the response receiving processor  253  receives a response like an execution result by the controller  4  that has executed an operation instructed in the worker command. 
     Referring back to  FIG. 1 , the user terminal  3  is a mobile terminal, such as a tablet terminal or a smartphone, and is utilized by the user like a resident of the residence H. Note that the user terminal  3  is not limited to such a mobile terminal, and may be a stationary terminal. As for an example structure of the user terminal  3 , an explanation is given with reference to  FIG. 4  which is a block diagram. As illustrated in the figure, the user terminal  3  includes a communicator  31 , display unit  32 , input unit  33 , a data memory  34 , and a control unit  35 . 
     The communicator  31  includes, for example, an interface for a wireless LAN connection that conforms to Wi-Fi (registered trademark) standards, and performs data communication with the controller  4  under the control of the control unit  35 . Note that the communication by the communicator  31  is not limited to the wireless communication, and communication via a wire like a wired LAN is also acceptable. 
     The display unit  32  includes a liquid crystal panel, and the like, and displays various screens, and the like under the control of the control unit  35 . For example, the display unit  32  displays an activation status screen with respect to the electrical device  5  that is managed by the controller  4 . 
     The input unit  33  includes a touch panel, a touch pad, and the like, and accepts an operation input made by the user. 
     The data memory  34  has a role of a so-called secondary memory device (auxiliary memory device), and includes, for example, a non-volatile readable and writable semiconductor memory like a flash memory. The data memory  34  stores a program to be executed by the control unit  35 , and various information necessary to execute the program. Note that the data memory  34  does not contain the terminal authentication information  241  stored in the worker terminal  2  (data memory  24 ). That is, a terminal authentication from the user terminal  3  is disabled. 
     The control unit  35  includes a CPU, a ROM, a RAM, and the like (all unillustrated), and controls each of the above-explained components. The control unit  35  includes, as a functional structure, a user command transmitting processor  351 , and a response receiving processor  352 . Those functions are realized by the CPU which utilizes the RAM as a work memory and which executes various programs as needed stored in the ROM and the data memory  34 . 
     The user command transmitting processor  351  transmits a user command that instructs, from the user, the operation to be executed by the controller  4 . For example, the user command transmitting processor  351  transmits a command to turn ON or OFF the electrical device  5 , a command to display the operation status of the electrical device  5 , and a command to change the operation of the electrical device  5 . Note that those commands are merely examples, and can be changed as needed in accordance with the type of the electrical device  5 . However, the commands to be transmitted by the user command transmitting processor  351  contain no worker command to be transmitted by the worker terminal  2  (worker command transmitting processor  252 ) as explained above. That is, the user command transmitting processor  351  is unable to transmit the command to delete the measurement data on the electrical device  5 , and the command to delete the information unique to the electrical device  5  and the user&#39;s personal information relating to the electrical device  5 . 
     The response receiving processor  352  receives a response to be transmitted by the controller  4  and corresponding to the user command transmitted to the controller  4  by the user command transmitting processor  351 . For example, the response receiving processor  352  receives a response like an execution result by the controller  4  that has executed an operation instructed in the worker command. 
     Referring back to  FIG. 1 , the controller  4  is, for example, a Home Energy Management System (HEMS) controller, and controls the entire home network system  1 . An example structure of the controller  4  is explained below with reference to  FIG. 5  which is a block diagram. As illustrated in the figure, the controller  4  includes a communicator  41 , a data memory  42 , and a control unit  43 . 
     The communicator  41  performs data communication with each electrical device  5  via the in-home network  9 . In addition, the communicator  41  performs data communication with the worker terminal  2  and the user terminal  3  via a wireless LAN, or the like. 
     The data memory  42  has a role of a so-called secondary memory device (auxiliary memory device), and includes, for example, a non-volatile readable and writable semiconductor memory like a flash memory. The data memory  42  stores device information  421 , and measurement data  422  both explained further below. In addition to these pieces of information, the data memory  42  stores a program, and the like to be executed by the control unit  43 . 
     First, an explanation is given of the device information  421  with reference to  FIG. 6 .  FIG. 6  is a schematic diagram illustrating example device information  421 . This device information  421  contains the information unique to the electrical device  5  and the user&#39;s personal information relating to the electrical device  5 . The information unique to the electrical device  5  is, for example, a device ID or a MAC address. In addition to these pieces of information, installation location information on the device and an IP address thereof may be further contained. Conversely, the user&#39;s personal information relating to the electrical device  5  is, for example, a name of the device (for example, a name set by the user) or a usage record. In addition to these pieces of information, a login ID of the user, a password, and further a combination of secret question and answer when the user forgets the password, and the like may be also contained. Note that such device information  421  is merely an example, and can be changed as needed in accordance with the type of the electrical device  5 . 
     Next, the measurement data  422  is explained with reference to  FIG. 7 .  FIG. 7  is a schematic diagram illustrating example measurement data  422 . This measurement data  422  contains an integrated power amount obtained by integrating the amount of power consumption of the electrical device  5 . In addition to such information, the measurement data  422  may further contain a cumulative activation time obtained by cumulating the activation time of the electrical device  5 . Note that such measurement data  422  is merely an example, and can be changed as needed in accordance with the type of the electrical device  5 . 
     Referring back to  FIG. 5 , the control unit  43  includes a CPU, a ROM, a RAM, and the like (all unillustrated), and controls each component explained above. The control unit  43  includes, as a functional structure, a worker terminal authenticator  431 , a command receiving processor  432 , a command executing processor  433 , and a response transmitting processor  434 . The functions of these components are realized by the CPU which utilizes the RAM as a work memory, and which executes various programs stored in the ROM or the data memory  42  as needed. 
     The worker terminal authenticator  431  authenticates the worker terminal  2  in accordance with a request. When, for example, an authentication request is transmitted from the worker terminal  2  (above-explained authentication requesting processor  251 ), the worker terminal authenticator  431  requests the worker terminal  2  to transmit information indicating the “worker terminal” Next, the worker terminal authenticator  431  checks, after transmission of the terminal authentication information  241  from the worker terminal  2 , the validity, and the like of such information, thereby authenticating the worker terminal  2 . 
     The command receiving processor  432  receives a command transmitted from the worker terminal  2  or the user terminal  3 . That is, the command receiving processor  432  receives the worker command transmitted from the worker terminal  2 , and also receives the user command transmitted from the user terminal  3 . 
     The command executing processor  433  executes an operation in accordance with a command received by the command receiving processor  432 . When, for example, the worker command is received by the command receiving processor  432 , the command executing processor  433  executes an operation necessary during the installation work or the maintenance work in accordance with the received worker command. As an example, in accordance with the command that instructs deletion (initialization) of measurement data (measurement data  422 ), the command executing processor  433  initializes the measurement data  422  stored in the data memory  42 . In addition, in accordance with the command that instructs deletion of the information unique to the former electrical device  5  and the user&#39;s personal information relating to the former electrical device  5 , the command executing processor  433  deletes the device information  421  stored in the data memory  42 . Note that in the case of the command that instructs deletion of such information, information to be deleted is defined beforehand in accordance with the installation work and the maintenance work. For example, in the case of the installation work, the measurement data  422  is the information to be deleted, while in the case of the maintenance work, the device information  421  is the information to be deleted. Hence, the command executing processor  433  deletes the instructed information among the pieces of information stored in the data memory  42  only when the received command is a command that instructs deletion of information defined in accordance with the work. Conversely, when the user command is received by the command receiving processor  432 , the command executing processor  433  controls the electrical device  5 , and reads information therefrom in accordance with such a user command. 
     Note that the command executing processor  433  executes an operation in accordance with the worker command only when the worker command is transmitted from the worker terminal  2  that has been authenticated by the worker terminal authenticator  431 . If the worker command is transmitted from the user terminal  3  that has not been authenticated by the worker terminal authenticator  431 , the command executing processor  433  transmits an error response from the response transmitting processor  434  which are explained further below without executing the instructed operation. 
     The response transmitting processor  434  transmits a response in accordance with the executed operation by the above-explained command executing processor  433  to the transmission originator (worker terminal  2  or user terminal  3 ) of the command. When, for example, the command executing processor  433  has executed the worker command, the response transmitting processor  434  transmits an execution result thereof to the worker terminal  2 . Likewise, when the command executing processor  433  has executed the user command, the response transmitting processor  434  transmits an execution result thereof to the user terminal  3 . 
     An explanation is given below of an operation of the home network system  1  with reference to  FIG. 8  and  FIG. 9 .  FIG. 8  is a sequence diagram illustrating an example basic sequence between the worker terminal  2  and the controller  4 , while  FIG. 9  is a sequence diagram illustrating a specific example of the basic sequence. 
     First, the basic sequence between the worker terminal  2  and the controller  4  is explained with reference to  FIG. 8 . First of all, the worker terminal  2  requests (Sq 101 ) a terminal authentication to the controller  4 . That is, the authentication requesting processor  251  requests the terminal authentication so as to permit the local worker terminal  2  to transmit the worker command. 
     When accepting the request for the terminal authentication (Sq 102 ), the controller  4  requests (Sq 103 ) the worker terminal  2  to transmit terminal authentication information (terminal authentication information  241  explained above). That is, the worker terminal authenticator  431  requests information indicating the “worker terminal” to the worker terminal  2 . 
     The worker terminal  2  transmits (Sq 104 ) the terminal authentication information (terminal authentication information  241 ) to the controller  4 . That is, the authentication requesting processor  251  reads the terminal authentication information  241  from the data memory  24 , and transmits the read information to the controller  4 . 
     The controller  4  authenticates (Sq 105 ) the worker terminal  2 . That is, after checking the validity, and the like of the received terminal authentication information  241 , the worker terminal authenticator  431  authenticates the worker terminal  2 . Next, the controller  4  permits (Sq 106 ) the worker terminal  2  to transmit the worker command. 
     Upon this permission-giving operation, the worker terminal  2  transmits (Sq 107 ) the worker command to the controller  4 . The controller  4  executes (Sq 108 ) an operation in accordance with the received worker command, and then transmits (Sq 109 ) a response to the worker terminal  2 . 
     Next, such interactive operations from Sq 107  to Sq 109  are explained more specifically with reference to  FIG. 9 .  FIG. 9  illustrates, as an example, a sequence when a command that instructs deletion (initialization) of the measurement data  422  is transmitted to the controller  4  during the installation work by the worker. 
     The worker terminal  2  transmits (Sq 107 ) the initialization command of the measurement data  422  to the controller  4 . That is, the worker command transmitting processor  252  transmits the command to initialize the measurement data  422  to the controller  4  since the amount of power consumption, and the like of the electrical device  5  is already measured through the activation of the electrical device  5  during the installation work, and the measurement data  422  is already stored in the data memory  42  of the controller  4 . 
     The controller  4  initializes (Sq 108 ) the measurement data (measurement data  422 ) in accordance with the received initialization command That is, the command executing processor  433  initializes the measurement data  422  stored in the data memory  42 . Next, the controller  4  transmits (Sq 109 ), to the worker terminal  2 , a response to the effect that the initialization of the measurement data  422  has completed. That is, the response transmitting processor  434  transmits, to the worker terminal  2 , a response indicating that the measurement data  422  in the data memory  42  has been initialized. 
     With reference to  FIG. 9 , explanation is given of the worker command (initialization command) transmitted during the installation work as an example, but other obtainment transmitted during the maintenance work are likewise processed. When, for example, during the maintenance work, a command that instructs deletion of the information unique to the former electrical device  5  or the user&#39;s personal information relating to the former electrical device  5  is transmitted in Sq 107  from the worker terminal  2 , the command executing processor  433  deletes (Sq 108 ) the device information  421  stored in the data memory  42 . Next, the response transmitting processor  434  transmits, to the worker terminal  2 , a response indicating that the deletion of the device information  421  has completed. 
     Such interactive operations between the worker terminal  2  and the controller  4  come into effect based on an assumption that the terminal authentication has been carried out successfully. Hence, for example, the user terminal  3  that has not undergone a terminal authentication does not transmit a worker command to the controller  4 . That is, the device information  421  and the measurement data  422  both stored in the controller  4  (data memory  42 ) are not deleted against the will of the user who operates the user terminal  3 . In addition, even if the user terminal  3  transmits a worker command, since such a user terminal has not undergone the terminal authentication, as explained above, the command executing processor  433  causes the response transmitting processor  434  to return an error response without executing the instructed operation. That is, a dishonest act (for example, falsification of information affecting billing) of the user becomes preventable. Consequently, appropriate deletion of information is enabled while enhancing a security. 
     Second Embodiment 
     According to the first embodiment, the worker command is transmitted from the worker terminal  2  to the controller  4 , and the controller  4  is capable of, for example, deleting (including initialization) information in the data memory  42  in accordance with such a worker command. However, because of, for example, an operation mistake by the worker, the work may conclude without a transmission, from the worker terminal  2  to the controller  4 , of a worker command necessary during the installation work or the maintenance work. Hence, a work procedure for the worker may be managed at the end of the worker terminal  2 . 
     In a second embodiment, as illustrated in  FIG. 10 , the worker terminal  2  differs from the worker terminal  2  of the first embodiment in that a work procedure information  242  is further stored in the data memory  24 . The work procedure information  242  is information that defines the sequential work details, and as an example, as illustrated in  FIG. 11 , the work procedure information  242  contains a number, a work detail, a worker command, and a completion-indicating flag. In this  FIG. 11 , the sequential work details at the time of installation work are defined, and the work details are presented to the worker in the order of number (ascending order). When the worker carries out the defined operation in accordance with the presented work details, a corresponding worker command is transmitted to the controller  4  from the worker command transmitting processor  252 . Next, when the response receiving processor  253  receives a normal response, the completion-indicating flag is set. In addition, when all completion-indicating flags in the work procedure information  242  are not set yet, the worker terminal  2  does not accept a completion of the work. 
     As explained above, according to the second embodiment, the work procedure for the worker is managed based on the work procedure information  242 , and thus a work procedure forgotten by the worker, and the like, is preventable. In addition, according to the second embodiment, explanation is given of an example case in which the work procedure information  242  is stored in the worker terminal  2  (data memory  24 ) to manage the work procedure for the worker, but such work procedure information  242  may be stored in the controller  4  (data memory  42 ), and the work procedure for the worker may be managed mainly by the controller  4 . Still further, both the worker terminal  2  and the controller  4  may store the work procedure information  242 , and may manage the work procedure for the worker by a mutual check up with each other. 
     Third Embodiment 
     In the first embodiment, and the like, explanation is given of an example case in which the measurement data  422  stored in the controller  4  (data memory  42 ) at the time of installation work of the electrical device  5  is initialized. However, for the purpose of maintenance, and the like for the electrical device  5 , information measured from the initial activation should be preferably left continuously in some cases. Hence, the measurement data  422  may be initialized so as to leave information from the initial activation. 
     In a third embodiment, as illustrated in  FIG. 12 , the controller  4  (data memory  42 ) differs from the controller  4  of the first embodiment in that the measurement data  422  containing an offset value is stored. As for the offset value in  FIG. 12 , when the measurement data  422  is initialized, a value of an integrated power amount at this time point is set. Note that at this time, the integrated power amount remains unchanged. That is, unlike the first embodiment in which the integrated power amount in the measurement data  422  is directly initialized, the offset value to be subtracted therefrom is updated to the same value, and thus the current integrated power amount obtained by the subtraction is initialized. 
     This is explained more specifically with reference to  FIG. 13 , and provided that the initialization command of the measurement data  422  is transmitted to the controller  4  from the worker terminal  2  at a time t 1  in accordance with the completion of the installation work. In this case, the controller  4  (command executing processor  433 ) sets an integrated power amount p 1  at the time point t 1  to be the offset value in  FIG. 12 . That is, the current integrated power amount obtained by the subtraction becomes the integrated power amount−the offset value (that is, p 1 −p 1 ), thus initialized to zero. Subsequently, the integrated power amount increases in accordance with the use by the user. Next, provided that, at a time t 2 , an obtaining command of the current integrated power amount is transmitted from the user terminal  3  to the controller  4 . In this case, the controller  4  (command executing processor  433 ) obtains the current integrated power amount based on the integrated power amount−the offset value (that is, p 2 −p 1 ), and transmits the obtained current integrated power amount to the user terminal  3 . 
     As explained above, according to the third embodiment, information containing the offset value to be subtracted from the integrated power amount is contained in the measurement data  422 , and when the measurement data  422  is initialized, the integrated power amount in the measurement data  422  is not directly initialized, but the offset value is updated to the value that is equal to the integrated power amount, and thus the current integrated power amount obtained by subtraction is initialized Hence, information measured from the initial activation of the electrical device  5  is left continuously, and thus such information is available for the maintenance work, and the like. Conversely, for the user (user terminal  3 ), the current integrated power amount obtained by subtracting the offset value from the integrated power amount in the measurement data  422  is transmitted, and thus data measured in accordance with the use by the user is appropriately providable. 
     In the foregoing embodiments, explanation is given of an example case in which the present disclosure is applied to the controller  4 , and the like, but the present disclosure is realizable by not only a special-purpose system but also a normal computer system. For example, the controller  4  that executes the above-explained process may be configured by distributing a computer program to carry out the above-explained operations in a manner stored in a non-transitory computer-readable recording medium (for example, a flexible disk, a CD-ROM, or a DVD-ROM), and by installing the computer program in a computer. In addition, the controller  4  may be configured by storing the computer program in a storage device of a server device on a communication network like the Internet, and by downloading the computer program to a normal computer system. 
     In addition, when the functions of the controller  4  are shared by an Operating System (OS) and an application program, or are realized by a cooperative work of the OS with the application program, only the application program portion may be stored in a non-transitory recording medium or a storage device. 
     Still further, the computer program may be superimposed on carrier waves, and may be distributed via a communication network. For example, the computer program may be posted on a Bulletin Board System (BBS) on a communication network, and may be distributed via the network. Next, the computer program may be launched, and executed like other application programs under the control of the OS to enable execution of the above-explained processes. 
     INDUSTRIAL APPLICABILITY 
     The present disclosure is appropriately applicable to a controller, a worker terminal, an information deletion method, and a program which are capable of appropriately deleting information while enhancing a security. 
     REFERENCE SIGNS LIST 
     
         
         
           
               1  Home network system 
               2  Worker terminal 
               3  User terminal 
               4  Controller 
               5  Electrical device 
               9  In-home network 
               21 ,  31 ,  41  Communicator 
               22 ,  32  Display unit 
               23 ,  33  Input unit 
               24 ,  34 ,  42  Data memory 
               25 ,  35 ,  43  Control unit