Abstract: A communication system transmits relay data through a communication path including a plurality of sections in which different communication schemes are used. A relay communication device is provided between a first section and a second section which are adjacent sections. The relay communication device includes a receiving unit receiving the relay data from the first section through a frame of a first communication scheme, and a relaying unit configuring, in a frame of a second communication scheme used to transmit the relay data to a relay destination, signal quality information representing signal quality calculated for a physical link in each of the sections through which the relay data is transmitted before arriving at the relay communication device, and outputting the frame of the second communication scheme to the second section.

Abstract: A transfer device includes a detection unit configured to detect a sign of a failure in a link between transfer devices, and a management unit configured to update a routing table to lower a priority of a path via the link when the sign of the failure is detected by the detection unit.

Abstract: A transmission apparatus includes a control unit for carrying out processing to secure a resource for a standby system path in response to detection of a sign of failure in an active system path.

Abstract: Provided is a particulate alkaline earth metal ion adsorbent having a large adsorption capacity. The particulate alkaline earth metal ion adsorbent comprising: a potassium hydrogen dititanate hydrate represented by a chemical formula K2-xHxO·2TiO2·nH2O, wherein x is 0.5 or more and 1.3 or less, and n is greater than 0; and no binder, wherein the particulate alkaline earth metal ion adsorbent has a particle size range of 150 ?m or more and 1000 ?m or less.

Abstract: Provided are a cobalt ion adsorption material which has a large adsorption capacity and which tends not to generate fine powder, and a method for producing the same. This cobalt ion adsorption material is a powder with a particle diameter of 100-1,000 ?m, and contains 0.3-8.0 parts by mass of a binder constituted of a water-insoluble metal oxide or metal hydroxide fine particles with respect to 100 parts by mass of a cobalt adsorption main agent constituted of potassium hydrogen dititanate hydrate.

Abstract: A state estimating device includes a pre-processing unit and an estimating unit. The pre-processing unit acquires data representing at one or more of a phase of a signal transmitted from a transmission unit of a transmission device and received at a reception unit of another transmission device via a transmission path, a reception strength, a reception quality, a voltage after conversion into an electric signal, and a signal processing parameter used in reception processing, and processes the acquired data into feature data to be used for state estimation. The estimating unit estimates a state of the transmission path, an abnormal state of the transmission unit, or an abnormal state of the reception unit, on the basis of the feature data.

Abstract: There is provided an optical transmission system in which a plurality of optical transmission and reception apparatuses perform 1-to-N transmission and reception of optical signals (N is an integer equal to or greater than 1), the optical transmission system being configured to select a communication condition that includes at least a modulation scheme or a baud rate and is a communication condition when each of the optical transmission and reception apparatuses performs transmission and reception in accordance with a transmission line condition that is between any one first optical transmission and reception apparatus and each of second optical transmission and reception apparatuses, which are N grounds, other than the first optical transmission and reception apparatus.

Abstract: The present invention provides a particulate cobalt ion adsorbent which has a high adsorption capacity. A particulate cobalt ion adsorbent which contains potassium hydrogen dititanate hydrate represented by chemical formula K2-XHxO.2TiO2.nH2O (wherein x is 0.5 or more and 1.3 or less, and n is greater than 0), and no binder, wherein the particulate cobalt ion adsorbent has a particle size range of 150 ?m or more and 1000 ?m or less.

Abstract: An optical transmission system including an optical transmission device and an optical reception device that receives, via an optical transmission line, a signal transmitted from the optical transmission device, the optical transmission system including a transmission-mode selection unit that selects transmission mode information in descending order of priority out of transmission mode information, which is combinations of a plurality of parameters concerning transmission performance, the transmission mode information being a plurality of kinds of the transmission mode information common to the transmission performance of the optical transmission device and the optical reception device, a signal transmission unit that transmits, to the optical reception device, a signal modulated based on the selected transmission mode information, and a signal reception unit that receives the signal and modulates the received signal based on the transmission mode information selected by the transmission-mode selection unit.

Abstract: An optical amplification system includes: three or more nodes; a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of the connection between the nodes; an amplification light input unit configured to input amplification light to a core of the plurality of cores of the multi-core fiber; an amplification unit configured to amplify communication light transmitted through at least one core of the plurality of cores of the multi-core fiber using the amplification light, the amplification unit being provided in the nodes or between the nodes; and an amplification light coupling unit configured to couple the amplification light input by the amplification light input unit to the amplification unit.

Abstract: A transmission device includes a frame processing unit, a redundant channel processing unit, a transmission and reception unit, and a channel selection unit. The frame processing unit generates division frames, adds error detection signals to the division frames, and outputs the division frames to which the error detection signals are added to a plurality of data channels. The redundant channel processing unit generates, from the division frames, one or more redundant frames including restoration information that enables restoration of the division frames, and outputs the generated redundant frames to a data channel. The transmission and reception unit outputs the division frames and the redundant frames to a transmission line. The channel selection unit allocates the division frames and the redundant frames to allocable transmission and reception units.

Abstract: A communication system transmits relay data through a communication path including a plurality of sections in which different communication schemes are used. A relay communication device is provided between a first section and a second section which are adjacent sections. The relay communication device includes a receiving unit receiving the relay data from the first section through a frame of a first communication scheme, and a relaying unit configuring, in a frame of a second communication scheme used to transmit the relay data to a relay destination, signal quality information representing signal quality calculated for a physical link in each of the sections through which the relay data is transmitted before arriving at the relay communication device, and outputting the frame of the second communication scheme to the second section.

Abstract: There is provided an optical transmission system in which a plurality of optical transmission and reception apparatuses perform 1-to-N transmission and reception of optical signals (N is an integer equal to or greater than 1), the optical transmission system being configured to select a communication condition that includes at least a modulation scheme or a baud rate and is a communication condition when each of the optical transmission and reception apparatuses performs transmission and reception in accordance with a transmission line condition that is between any one first optical transmission and reception apparatus and each of second optical transmission and reception apparatuses, which are N grounds, other than the first optical transmission and reception apparatus.

Abstract: A state estimating device includes a pre-processing unit and an estimating unit. The pre-processing unit acquires data representing at one or more of a phase of a signal transmitted from a transmission unit of a transmission device and received at a reception unit of another transmission device via a transmission path, a reception strength, a reception quality, a voltage after conversion into an electric signal, and a signal processing parameter used in reception processing, and processes the acquired data into feature data to be used for state estimation. The estimating unit estimates a state of the transmission path, an abnormal state of the transmission unit, or an abnormal state of the reception unit, on the basis of the feature data.

Abstract: A transmission quality estimation system includes, three or more nodes and a transmission quality estimation device configured to estimate, transmission quality. A multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes. A node of the nodes includes a core connection unit configured to drop, add or relay light transmitted from, to or to each of to the plurality of cores of the multi-core fiber. The transmission quality estimation device includes an estimation unit configured to estimate transmission quality between the nodes on the basis of a transmission quality measurement light dropped by the core connection unit.

Abstract: A transmission quality estimation system includes, three or more nodes and a transmission quality estimation device configured to estimate, transmission quality. A multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes. A node of the nodes includes a core connection unit configured to drop, add or relay light transmitted from, to or to each of to the plurality of cores of the multi-core fiber. The transmission quality estimation device includes an estimation unit configured to estimate transmission quality between the nodes on the basis of a transmission quality measurement light dropped by the core connection unit.

Abstract: A communication system which includes: three or more nodes; a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes; a detection signal output unit configured to output a fault detection signal transmitted by the core provided in the multi-core fiber configured to connect together the nodes; and a fault detection unit configured to determine whether a fault has occurred between the nodes on the basis of a detection result of the fault detection signal.

Abstract: Accommodation design for wavelength and sub-? paths in a communication network is performed. If sub-? path accommodation is possible according to search for a wavelength path present in a single-hop logical route, the accommodation in the wavelength path is executed. If sub-? path accommodation is possible according to search for a wavelength path present in a multi-hop logical route, a logical route is selected based on the wavelength path and the sub-? path is accommodated in the wavelength path. Additionally, each physical route suitable for the sub-? path accommodation is searched for. If the route can accommodate a wavelength path set in a single-hop logical route by available wavelength allocation, the sub-? path is accommodated in the wavelength path. Furthermore, routes in consideration of overlapping of nodes, pipelines, and links and operation rate are selected based on information about the start and end nodes of each of redundant routes.

Abstract: Provided is a particulate alkaline earth metal ion adsorbent having a large adsorption capacity. The particulate alkaline earth metal ion adsorbent comprising: a potassium hydrogen dititanate hydrate represented by a chemical formula K2-xHxO.2TiO2.nH2O, wherein x is 0.5 or more and 1.3 or less, and n is greater than 0; and no binder, wherein the particulate alkaline earth metal ion adsorbent has a particle size range of 150 ?m or more and 1000 ?m or less.

Abstract: A communication system includes three or more nodes and a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of the connection between the nodes is provided. One node of the nodes is connected to the multi-core fiber and includes a connector configured to add and drop a signal to and from an allocated core exclusively allocated from among the cores as a communication path between the one node and another node of the nodes and/or configured to relay a signal transmitted through another core of the cores allocated for communication between other nodes in the multi-core fiber connected to the one node, and a relative positional relationship between a connection position of the allocated core in which a signal is added or dropped in the connector and a connection position of another core in which a signal is relayed in the connector is the same for all of the nodes connected to the multi-core fiber.