Abstract: A heat exchanger includes: refrigerant channels that extend in a first direction, are disposed along a second direction intersecting with the first direction, and are disposed along a third direction intersecting with the first direction and the second direction; and heat transfer tubes defining the refrigerant channels. One or both of a size of an outer edge and a size of an inner edge of the heat transfer tubes are different between a first position and a second position in the first direction. Outer surfaces of the heat transfer tubes each include a protrusion that protrudes in a direction intersecting with the first direction, and is in contact with an outer surface of one of the heat transfer tubes adjacent thereto in the second direction. The protrusion includes a concave portion extending along the third direction.

Abstract: The control section of a control apparatus executes a first control for operating a voltage application section such as to cause a current to flow in a first direction through a gas sensor in a first period, and a second control for operating the voltage application section such as to cause a current to flow in a second direction, opposite to the first direction, through the gas sensor in a second period. The control apparatus changes the length of at least one of the first period and the second period based on a comparison between a first measurement value, which is the absolute value of a value measured by a sweep measurement section during execution of the first control, and a second measurement value, which is the absolute value of a value measured by the sweep measurement section during execution of the second control.

Abstract: The control section of a control apparatus executes a first control for operating a voltage application section such as to cause a current to flow in a first direction through a gas sensor in a first period, and a second control for operating the voltage application section such as to cause a current to flow in a second direction, opposite to the first direction, through the gas sensor in a second period. The control apparatus changes the length of at least one of the first period and the second period based on a comparison between a first measurement value, which is the absolute value of a value measured by a sweep measurement section during execution of the first control, and a second measurement value, which is the absolute value of a value measured by the sweep measurement section during execution of the second control.

Abstract: A transmission system includes a plurality of nodes in which respective adjacent nodes are coupled by a first kind of optical fiber compatible with light in a first wavelength band or a second kind of optical fiber compatible with light in a second wavelength band, wherein each of the plurality of nodes includes a transmitting node that generates a wavelength-multiplexed optical signal in the first wavelength band by carrying out wavelength multiplexing of a plurality of optical signals and transmits the wavelength-multiplexed optical signal, a receiving node that demultiplexes the plurality of optical signals from the wavelength-multiplexed optical signal and receives the plurality of optical signals, and one or more relay nodes that relay the wavelength-multiplexed optical signal from the transmitting node to the receiving node through the first kind or the second kind of optical fiber.

Abstract: A transmission system includes a plurality of nodes in which respective adjacent nodes are coupled by a first kind of optical fiber compatible with light in a first wavelength band or a second kind of optical fiber compatible with light in a second wavelength band, wherein each of the plurality of nodes includes a transmitting node that generates a wavelength-multiplexed optical signal in the first wavelength band by carrying out wavelength multiplexing of a plurality of optical signals and transmits the wavelength-multiplexed optical signal, a receiving node that demultiplexes the plurality of optical signals from the wavelength-multiplexed optical signal and receives the plurality of optical signals, and one or more relay nodes that relay the wavelength-multiplexed optical signal from the transmitting node to the receiving node through the first kind or the second kind of optical fiber.

Abstract: In a solar heat collector, a bottom plate and a side plate of a case which is opened in an upper surface are formed of a vacuum thermal insulation material in which a core material is enveloped by a skin and a vacuum is created in an interior of the skin, the skin is formed by welding together circumferential edges of two metal panels which are disposed to face each other with the core material sandwiched therebetween, a plurality of line grooves are formed in the metal panels, and the two metal panels are disposed so that sides thereof from which bottoms of the line grooves protrude are oriented inwards with the core material sandwiched therebetween.

Abstract: In a solar heat collector, a bottom plate and a side plate of a case which is opened in an upper surface are formed of a vacuum thermal insulation material in which a core material is enveloped by a skin and a vacuum is created in an interior of the skin, the skin is formed by welding together circumferential edges of two metal panels which are disposed to face each other with the core material sandwiched therebetween, a plurality of line grooves are formed in the metal panels, and the two metal panels are disposed so that sides thereof from which bottoms of the line grooves protrude are oriented inwards with the core material sandwiched therebetween.

Abstract: An optical amplifying device disposed on a transmission path of a WDM signal includes an optical amplifier amplifying the WDM signal, a detecting unit detecting a change in a transmission wavelength count contained in the WDM signal and/or a change in light receiving level of the optical amplifier, a measuring unit measuring an optical signal to noise (SN) ratio of the WDM signal outputted from the optical amplifier, an update unit updating a reference value for evaluating the measurement value of the optical SN ratio obtained by the measuring unit when the detecting unit detects the change, a judging unit judging whether or not the measurement value deviates from an allowable range based on a reference value, and an output unit outputting an error of the optical amplifier if the measurement value deviates from the allowable range.

Abstract: An optical transmission system includes an optical wavelength branching unit that shifts a wavelength transmission band in the short-wavelength or long-wavelength directions based on a branching filter operation temperature, and performs a branching operation on a wavelength-multiplexed signal. A reception transponder performs decoding on an error correction code. An error correction monitoring unit gathers an error correction amount upon which a branching filter temperature control unit sets the branching filter operation temperature. A transmission transponder performs encoding on an error correction code. An optical wavelength combining unit shifts the wavelength transmission band in the opposite direction from the shifting direction based on a combining filter operation temperature, to perform a combining operation on optical signals and output a wavelength-multiplexed optical signal.

Abstract: The invention relates to a method of activating an optical communication system comprising a plurality of optical amplifiers having an optical amplifier, between optical transmission lines in which wavelength-division multiplex optical signals are transmitted. The method comprises steps of: generating a desired slope in a desired wavelength range of a gain wavelength curve of the optical amplifier; adjusting an output of the optical amplifier to a desired output level; performing the above two steps in a plurality of optical repeater stations, the steps being carried out in sequence from the first to the last optical repeater stations; and adjusting a level in each optical signal in the wavelength-division multiplex optical signal so as to have substantially constant optical signal-to-noise ratios in the optical signals to be received. Activating the optical communication system according to this procedure allows proper execution of gain slope compensation, output control, and pre-emphasis control.

Abstract: The present invention provides a hologram screen which is capable of preventing separation, and damage to, a hologram film and which permits the hologram film to be reused easily. The present invention relates to a hologram screen that is comprised of a hologram film having the function of diffracting the light projected from a projector, and first and second transparent members that together sandwich the hologram film from the front and back surfaces thereof so as to cover the same.

Abstract: An acceleration detecting device comprising a mass body inserted in a casing so as to be movable in the forward and backward direction, an elastic member for biasing the mass body backward, stationary contacts provided on the casing, moving contacts provided on the mass body, and auxiliary moving contacts also provided on the mass body, wherein the moving contacts contact with the stationary contacts when acceleration applied to the mass body causes the mass body to advance a predetermined distance against the bias of the elastic member, and when the mass body advances further and the mass body collides against the casing, the auxiliary moving contacts contact with the stationary contacts at the distal end of the range in which the mass body moves.

Abstract: An acceleration detecting device comprising a mass body inserted in a casing so as to be movable in the forward and backward direction, an elastic member for biasing the mass body backward, stationary contacts provided on the casing, moving contacts provided on the mass body, and auxiliary moving contacts also provided on the mass body, wherein the moving contacts contact with the stationary contacts when acceleration applied to the mass body causes the mass body to advance a predetermined distance against the bias of the elastic member, and when the mass body advances further and the mass body collides against the casing, the auxiliary moving contacts contact with the stationary contacts at the distal end of the range in which the mass body moves.

Abstract: An optical transmission system according to the present invention is directed to achieving higher transmission quality by improving AWG transmission characteristics. An optical wavelength branching unit shifts a wavelength transmission band in the short-wavelength direction or the long-wavelength direction based on a branching filter operation temperature, and performs a branching operation on a wavelength-multiplexed signal. A reception transponder performs decoding on an error correction code. An error correction monitoring unit gathers an error correction amount. A branching filter temperature control unit sets the branching filter operation temperature based on the error correction amount. A transmission transponder performs encoding on an error correction code.

Abstract: A display apparatus according to one aspect of the first invention includes: an irradiating unit for generating signal light which records information to be displayed; a light-transmitting type screen (or hologram screen) which transmits the signal light input by the irradiating unit to an observer; and a reflection preventing member provided to either both sides, i.e., observer's side and rear side, or any one side, of the light-transmitting type screen (or hologram screen).

Abstract: An image information displaying system comprises a transparent support, a hologram screen attached to the transparent support, a radiation unit for radiating image information on the hologram screen, a sensor for detecting the ambient condition within the viewing angle of the hologram screen, and a controller for controlling the radiation unit based on the signal from the sensor. The image information displaying system, which is inexpensive, long in service life, superior in eye-catching effect and low in running cost, consumes less energy and is controlled by a central control unit connected thereto through a communication line. The lower-end of the hologram screen is 80 to 180 cm from the floor level.

Abstract: The present invention discloses a fault indicator circuit in a system having a plurality of circuit blocks each provided with an individual power source. Each of the circuit blocks needs to indicate a fault when a fault occurs in the individual power source of the circuit block. The fault indicator circuit of the present invention includes a fault indicator which performs fault indication in response to a fault indication control signal from the circuit block having the fault or one of the other circuit blocks. When a fault occurs in the individual power source of a circuit block, the fault indicator performs fault indication by means of power supplied from the individual power source of one of the other circuit blocks. An input determiner which reduces the level of the fault indicator control signal outputted from one of the other circuit blocks is disposed at the input terminal of a gate circuit into which the fault indication control signal is inputted from one of the other circuit blocks.

Abstract: An image information displaying system comprises a transparent support, a hologram screen attached to the transparent support, a radiation unit for radiating image information on the hologram screen, a sensor for detecting the ambient condition within the viewing angle of the hologram screen, and a controller for controlling the radiation unit based on the signal from the sensor. The image information displaying system, which is inexpensive, long in service life, superior in eye-catching effect and low in running cost, consumes less energy and is controlled by a central control unit connected thereto through a communication line. The lower end of the hologram screen is 80 to 180 cm from the floor level.

Abstract: The invention relates to a method of activating an optical communication system comprising a plurality of optical amplifiers having an optical amplifier, between optical transmission lines in which wavelength-division multiplex optical signals are transmitted. The method comprises steps of: generating a desired slope in a desired wavelength range of a gain wavelength curve of the optical amplifier; adjusting an output of the optical amplifier to a desired output level; performing the above two steps in a plurality of optical repeater stations, the steps being carried out in sequence from the first to the last optical repeater stations; and adjusting a level in each optical signal in the wavelength-division multiplex optical signal so as to have substantially constant optical signal-to-noise ratios in the optical signals to be received. Activating the optical communication system according to this procedure allows proper execution of gain slope compensation, output control, and pre-emphasis control.

Abstract: The present invention provides a hologram screen which is capable of preventing separation, and damage to, a hologram film and which permits the hologram film to be reused easily. The present invention relates to a hologram screen that is comprised of a hologram film having the function of diffracting the light projected from a projector, and first and second transparent members that together sandwich the hologram film from the front and back surfaces thereof so as to cover the same.