Abstract: A power conversion device includes a power converter connected between a multi-phase alternating-current circuit and a direct-current circuit, and a control device to control the power converter. The control device detects an unbalanced component indicating a voltage unbalanced component or a current unbalanced component of the alternating-current circuit and limits a magnitude of an alternating current flowing between the power converter and the alternating-current circuit based on the unbalanced component.

Abstract: An objective of the present invention is to use a calculation model to calculate, with good accuracy, behavior of electromagnetic waves within an actual service area. Provided is a radio environment evaluation method that includes constructing, within a computer resource, a structural model for an electromagnetic wave scatterer, and when calculating a characteristic of an electromagnetic field by using the structural model and a ray that simulates a radio wave traveling straight through real space, correcting, in accordance with electromagnetic wave vector measurement data for real space, a state of a polygon included in the structural model.

Abstract: A receiver mounted on a vehicle moving on a route manages an operation profile that stores data in which a section that is a part of the route and a communication quality in the section are associated, and can receive a first traffic and a second traffic having a lower priority than the first traffic. The receiver determines a section having a good communication quality to a transmission section where the second traffic can be transmitted with reference to the operation profile, and generates control information for controlling transmission of the second traffic not to hinder transmission of the first traffic when the vehicle is located in the transmission section.

Abstract: It is provided a communication device which transfers a signal, comprising: an arithmetic device configured to execute predetermined processing; a storage device accessible from the arithmetic device; a log collection module configured to collect first type logs from at least one of the communication device or an equipment coupled to the communication device; an alert generation module configured to generate alert when one of the collected the first type logs satisfies a predetermined condition; and a failure cause candidate determination module configured to determine failure cause candidates in response to the generated alert, and output, to the log collection module, an additional log collection request for collecting second type logs in an additional log collection order that is set based on the determined failure cause candidates.

Abstract: A processor of a sensor device performs measurement processing by one or a plurality of sensors and transmission processing of sensor data generated by the measurement processing. The sensor device includes a processing routine table that stores a processing routine configured to include, corresponding to an identifier for identifying processing performed by a processor, a type of the processing, an execution trigger of the processing, and trigger information that prescribes a trigger for transmitting the sensor data. The processor controls processing in a processing routine of the processing routine table, based on trigger information, so that the sensor data subjected to measurement processing is immediately transmitted, or temporarily stored in a buffer and transmitted after a predetermined time.

Abstract: A monitoring system includes a plurality of sensor terminals installed for a target to be measured, a base station wirelessly communicating with the sensor terminals, and a calculator communicable with the base station. The sensor terminal includes a sensor element which acquires vibration information of a target to be measured, an arithmetic unit which performs an arithmetic operation for data including the vibration information of the sensor element, and a wireless communication unit. The arithmetic unit performs a reduction process for reducing an amount of data of the sensor element. The wireless communication unit transmits data processed by the arithmetic unit to the base station. After the transmitted data is received, the base station transmits it to the calculator. The calculator includes a signal processing unit. The signal processing unit complements the reduction-processed data to acquire vibration information, and averages the vibration information for a predetermined period of time.

Abstract: A receiver mounted on a vehicle moving on a route manages an operation profile that stores data in which a section that is a part of the route and a communication quality in the section are associated, and can receive a first traffic and a second traffic having a lower priority than the first traffic. The receiver determines a section having a good communication quality to a transmission section where the second traffic can be transmitted with reference to the operation profile, and generates control information for controlling transmission of the second traffic not to hinder transmission of the first traffic when the vehicle is located in the transmission section.

Abstract: An object of the present invention is to prevent wrong registration due to an operation error and an input error in installation work of a sensor device. A terminal acquires a first identifier which the sensor device has and further, acquires positional information using a positioning device. The terminal transmits the first identifier and the positional information respectively acquired to a management server. The sensor device transmits a second identifier held by itself to the management server. The management server correlates the second identifier and the positional information when the management server judges that the first identifier and the second identifier are located in predetermined relation, registers them in a storage, and the management server notifies the sensor device of a result of the judgment.

Abstract: A management server 103 holds a parameter of a sensor device 101 and change management information related to a change in the parameter, and transmits the changed parameter and the change management information to the sensor device. The sensor device 101 holds the parameter and the change management information transmitted from the management server, and transmits the change management information to the management server together with measurement data. The management server collates the received change management information and preliminarily-held change management information to determine the change in the parameter on the basis of a result of the collation.

Abstract: An object of the present invention is to improve an antenna for IoT services intended for things that constitute an internal space. There is provided an antenna device including an antenna and a dielectric body. In an internal space which is constituted by plural faces including a first face which is an electrically conductive body, the antenna device is adapted to have a shape to be fit inside a hole in the first face. The antenna device is installed, not protruding from the hole to an outer space. The antenna and the dielectric body are placed in series between the internal space and the outer space.

Abstract: An antenna device includes a conductive manhole cover for partitioning an internal space of a manhole and an external space, a wireless device installed in the internal space, and a base station that is installed in the external space and transfers a radio wave with respect to the wireless device. When a notch portion is formed on the edge of the manhole cover and the manhole cover is attached to an opening of the manhole, a slot-shaped void is formed. By using this void as a slot antenna, radio waves from the wireless device can be re-emitted to the external space. With such a configuration, it is not necessary to specially prepare a slot antenna, and a low-cost antenna device can be realized.

Abstract: A processor 204 of a sensor device performs measurement processing by one or a plurality of sensors 203 and transmission processing of sensor data generated by the measurement processing. The sensor device includes a processing routine table 211 that stores a processing routine configured to include, corresponding to an identifier for identifying processing performed by a processor, a type of the processing, an execution trigger of the processing, and trigger information that prescribes a trigger for transmitting the sensor data. The processor controls processing in a processing routine of the processing routine table, based on trigger information, so that the sensor data subjected to measurement processing is immediately transmitted, or temporarily stored in a buffer 212 and transmitted after a predetermined time.

Abstract: A communication device that performs bidirectional multiplex communication between a plurality of slave communication devices and the communication device is provided with: a first port connected to one end section of a transmission line to which the slave communication devices are connected; a second port connected to the other end section of the transmission line; and a current detection unit connected to the first port and the second port. An operation voltage is supplied from the communication device to the slave communication devices, a change of the quantity of a current flowing in the first port and/or the second port is detected by means of the current detection unit, and on the basis of the current quantity change, occurrence of disconnection in the transmission line is detected.

Abstract: A management server 103 holds a parameter of a sensor device 101 and change management information related to a change in the parameter, and transmits the changed parameter and the change management information to the sensor device. The sensor device 101 holds the parameter and the change management information transmitted from the management server, and transmits the change management information to the management server together with measurement data. The management server collates the received change management information and preliminarily-held change management information to determine the change in the parameter on the basis of a result of the collation.

Abstract: A monitoring system includes a plurality of sensor terminals installed for a target to be measured, a base station wirelessly communicating with the sensor terminals, and a calculator communicable with the base station. The sensor terminal includes a sensor element which acquires vibration information of a target to be measured, an arithmetic unit which performs an arithmetic operation for data including the vibration information of the sensor element, and a wireless communication unit. The arithmetic unit performs a reduction process for reducing an amount of data of the sensor element. The wireless communication unit transmits data processed by the arithmetic unit to the base station. After the transmitted data is received, the base station transmits it to the calculator. The calculator includes a signal processing unit. The signal processing unit complements the reduction-processed data to acquire vibration information, and averages the vibration information for a predetermined period of time.

Abstract: An object of the present invention is to prevent wrong registration due to an operation error and an input error in installation work of a sensor device. A terminal acquires a first identifier which the sensor device has and further, acquires positional information using a positioning device. The terminal transmits the first identifier and the positional information respectively acquired to a management server. The sensor device transmits a second identifier held by itself to the management server. The management server correlates the second identifier and the positional information when the management server judges that the first identifier and the second identifier are located in predetermined relation, registers them in a storage, and the management server notifies the sensor device of a result of the judgment.

Abstract: An object of the present invention is to improve an antenna for IoT services intended for things that constitute an internal space. There is provided an antenna device including an antenna and a dielectric body. In an internal space which is constituted by plural faces including a first face which is an electrically conductive body, the antenna device is adapted to have a shape to be fit inside a hole in the first face. The antenna device is installed, not protruding from the hole to an outer space. The antenna and the dielectric body are placed in series between the internal space and the outer space.

Abstract: Provided is a method for effectively suppressing packet losses by burst losses without an increase in delay by adaptively or fixedly changing a size of an FEC encoded block even when the number of packets per unit time is small. Each communication device 101 includes a transmitting unit 102 and a receiving unit 103. The transmitting unit 102 has a function of calculating forward error correction (FEC) codes based on the number of packets per encoding time and a value of a burst loss time of a network line. The receiving unit 103 decodes an FEC encoded packet and measures line quality information of the network for transmission to the transmitting unit 102. The transmitting unit 102 transmits the packets at equal intervals for as long as it is required for encoding, and can change a system for calculating FEC based on the burst loss time and the encoding time.

Abstract: It is necessary to increase the scale of a sensor network to achieve high resource exploration efficiency. On the other hand, since there are increasing needs to extend the area of an exploration region and to detect deeper geological stratum and crust structures more accurately, the large-scale sensor network needs to be operated for a long period of several weeks or longer. In order to solve the problem, a sensor unit needs to be turned on always to perform measurement always. However, an auxiliary measurement unit is activated intermittently since the auxiliary measurement unit needs to acquire data at necessary timings only. On the other hand, during collection and transmission of data and charging of a battery, a sensor terminal detects whether power is supplied from a data collection and charging device and automatically turns off the sensor unit and the auxiliary measurement unit to activate a data transmission unit.

Abstract: Provided are a device, a system, and a method in which redundancy is changed in accordance with a line state, and thus the optimal redundancy can be set while the current settings are compared to the previous settings. A communication device measures line quality information from a received packet, and generates a redundancy change instruction based on information regarding a line. In a case where the communication device acquires line quality information for the second and subsequent times, the communication device compares the previous redundancy change instruction and the previous line quality information, to the current line quality information, and sets redundancy. Thus, it is possible to suppress the occurrence of congestion and satisfy a target value of the line quality, and to search for a condition which causes the redundancy to be the minimum.