Abstract: In a ship control system of one embodiment, a route command unit outputs a route command including a target ship position and a target bow direction of a ship. An information detector detects ship information including an actual ship position and an actual bow direction of a ship. An external force vector estimation unit estimates an external force vector received by a ship, using the ship information and a hull motion model related to a hull motion of the ship. A control command unit controls both rotational frequency of a main engine and a rudder angle of a ship, based on the route command, the ship information, and the external force vector.

Abstract: A ship monitoring system includes: a shipboard information processing apparatus and including a shipboard communication unit and an information acquisition unit; and a support information processing apparatus and including: a support side communication unit capable of communicating with the shipboard communication unit; a time lag identification unit; and a state prediction unit. The time lag identification unit identifies a time from transmission of the ship motion information from the shipboard communication unit to reception of the ship motion information by the support side communication unit as a reception time lag. The state prediction unit inputs the ship motion information and the reception time lag to a ship motion model related to the ship motion of the ship to predict a motion state of the ship ahead of a motion state of the ship indicated by the ship motion information by a period of time based on the reception time lag.

Abstract: In a ship control system of one embodiment, a main engine controller performs, when controlling the rotational frequency of a main engine based on a target ship speed of a ship, feedback control of an actual ship speed of the ship to perform ship speed control for bringing the actual ship speed closer to the target ship speed. A turning judgment unit judges whether or not the ship will turn. A control change unit performs, when the turning judgment unit has judged that the ship will turn, lowering processing for lowering the responsiveness of the ship speed control.

Abstract: An audio teleconferencing apparatus which permits two-way communications between more than two parties without the necessity of complete switching and does not allow a loss to increase in a communication channel of a particular speaker. The audio teleconferencing apparatus further comprises more than two line interface circuits, each provided with a voice activity detector for detecting voice activity in a received speech signal, a received-speech variable loss for inserting a loss into a speech receiving path when the received speech signal is voice non-active, and a sending-speech variable loss for inserting a loss in a speech signal transmission or sending path when the speech to be sent is voice-active, whereby a certain loss is inserted in any four-wire multiplex loop in the line interface circuit.

Abstract: A synchronizing system in a digital communication line comprises a plurality of local switches for storing at least one digital line and monitoring a first piece of busy information when a clock source is already present, the local switches, if a first new clock source occurs while the first busy information is indicating no busy state, being capable of transmitting a master right request to turn the busy information to the busy state and to specify the first new clock source as a master clock and, on receiving a master right specification with respect to the master right request, being capable of outputting the first new clock source as the master clock; and a master switch connected to the plurality local switches in a star manner, by a link transmission line for transmitting control information including the master clock, master right request and master right specification, for monitoring a second piece of busy information indicating a busy state, the master switch, if a second new clock source occurs whil