Abstract: According to one embodiment, a spatial position measurement apparatus, includes: a transmission unit configured to transmit an ultrasonic wave accompanying with a transmission source identifiable from three or more transmission sensors provided on a first object; a detection unit configured to detect the ultrasonic wave received by two or more reception sensors provided on a second object; a distance calculation unit configured to calculate distances between the transmission sensors and the reception sensors based on propagation time of the ultrasonic wave; and a coordinate calculation unit configured to calculate, in a coordinate system where a position of one group out of a group of the transmission sensors and a group of the reception sensors is fixed, positional coordinates of another group based on the distances.

Abstract: According an embodiment, a liquid storage system comprises a tank for storing liquid fuel, a vent pipe for providing communication between outside of the tank and a gas space above a level of liquid fuel in the tank, a nonflammable gas supplying apparatus for supplying the gas space with nonflammable gases, a pressure control apparatus installed in the vent pipe to operate responsively to the pressure difference between the gas space and atmospheric pressure so as to limit a pressure in the gas space to a predetermined range. The pressure control apparatus introduces ambient air outside the tank into the gas space through the vent pipe when a pressure in the gas space is lower than a predetermined lower limit, and discharge a gas from the gas space out of the tank through the vent pipe when a pressure in the gas space is higher than a predetermined upper limit.

Abstract: According an embodiment, a liquid storage system comprises a tank for storing liquid fuel, a vent pipe for providing communication between outside of the tank and a gas space above a level of liquid fuel in the tank, a nonflammable gas supplying apparatus for supplying the gas space with nonflammable gases, a pressure control apparatus installed in the vent pipe to operate responsively to the pressure difference between the gas space and atmospheric pressure so as to limit a pressure in the gas space to a predetermined range. The pressure control apparatus introduces ambient air outside the tank into the gas space through the vent pipe when a pressure in the gas space is lower than a predetermined lower limit, and discharge a gas from the gas space out of the tank through the vent pipe when a pressure in the gas space is higher than a predetermined upper limit.

Abstract: According to one embodiment, a spatial position measurement apparatus, includes: a transmission unit configured to transmit an ultrasonic wave accompanying with a transmission source identifiable from three or more transmission sensors provided on a first object; a detection unit configured to detect the ultrasonic wave received by two or more reception sensors provided on a second object; a distance calculation unit configured to calculate distances between the transmission sensors and the reception sensors based on propagation time of the ultrasonic wave; and a coordinate calculation unit configured to calculate, in a coordinate system where a position of one group out of a group of the transmission sensors and a group of the reception sensors is fixed, positional coordinates of another group based on the distances.

Abstract: According to one embodiment, a spatial position measurement apparatus, includes: a transmission unit configured to transmit an ultrasonic wave accompanying with a transmission source identifiable from three or more transmission sensors provided on a first object; a detection unit configured to detect the ultrasonic wave received by two or more reception sensors provided on a second object; a distance calculation unit configured to calculate distances between the transmission sensors and the reception sensors based on propagation time of the ultrasonic wave; and a coordinate calculation unit configured to calculate, in a coordinate system where a position of one group out of a group of the transmission sensors and a group of the reception sensors is fixed, positional coordinates of another group based on the distances.

Abstract: According to one embodiment, a spatial position measurement apparatus, includes: a transmission unit configured to transmit an ultrasonic wave accompanying with a transmission source identifiable from three or more transmission sensors provided on a first object; a detection unit configured to detect the ultrasonic wave received by two or more reception sensors provided on a second object; a distance calculation unit configured to calculate distances between the transmission sensors and the reception sensors based on propagation time of the ultrasonic wave; and a coordinate calculation unit configured to calculate, in a coordinate system where a position of one group out of a group of the transmission sensors and a group of the reception sensors is fixed, positional coordinates of another group based on the distances.