Abstract: A CATV station apparatus 100 subjects received optical signals to processes of optical-electrical conversion, signal separation, coupling, and demodulation for obtaining an uplink signal. A received photocurrent monitoring section 170 compares a received photocurrent at a optical receiving section 110 with a predetermined reference current. If the received photocurrent is equal to or higher than the reference current, an amplifying section 130 amplifies a signal output from a signal separating section 120 at a predetermined level. If the received photocurrent is lower than the reference current, on the other hand, it is determined that a non-linear phenomenon, such as stimulated Brillouin scattering, has occurred in an optical fiber 200. The amplifying section 130 then outputs a signal at a level which does not affect, even after being coupled with other signals, communications performed by other optical transmission systems.

Abstract: The invention provides a NOx removal system for use in a boiler for realizing further reduction in NOx. Loading means for loading a reducing agent is provided at the outlet of a gas passageway in the boiler body, and a NOx removal catalyst is provided downstream of the loading means.

Abstract: A NOx removal system for boilers in which the need for any special heat retention means or any warming means is eliminated. Ammonia jet nozzles are disposed on a gas passage of a boiler or flue, and ammonia generating means connected to the jet nozzles is disposed within the flue.

Abstract: A light emitting section 12 outputs an optical signal having an intensity corresponding to a transmission timing signal 81, the optical signal modulated based on a radio transmission signal 82. A received photocurrent detection section 22 detects an intensity of an optical signal received by a light receiving section 21. In accordance with the detected intensity, a high frequency amplification section 23 amplifies the output signal of the light receiving section 21, and a transmission timing signal reconstruction section 24 reconstructs the transmission timing signal. The use of the light emitting section 12 outputting no optical signal in a non-transmission state and the use of the high frequency amplification section 23 outputting no signal in the non-transmission state allow noise caused in an antenna side base station 20 in the non-transmission state to be reduced.

Abstract: A method for controlling a NOx removal system in which reductant supply is adjusted according to combustion level in a boiler (1) in which the combustion level is controlled in multiple stages. For a decrease of the combustion level, the reductant supply is kept lower than a level corresponding to a changeover-target combustion level for a period of a set time from the changeover of the combustion level. Thus, when the reductant supply is changed over in response to a changeover of combustion level, the reductant can be prevented from flowing outside as it is unreacted.

Abstract: An optical coaxial hybrid transmission system capable of quickly achieving high-speed Internet access at low cost without making any substantial changes to a transmission path of the existing system is provided. In this system, m-channel communications signals having frequencies of f1 to fm (Hz) corresponding to micro-cells 51 are converted into optical signals having different wavelengths by communications signal optical transmitters 102. These optical signals are wavelength-multiplexed by a communications signal wavelength multiplexer 103, and then wavelength-multiplexed by a video/communications signal wavelength multiplexer 104 with an optical signal modulated with a video signal. The resultant wavelength-multiplexed optical signal is transmitted to a node 30. In the node 30, the wavelength-multiplex optical signal is demultiplexed, and the video signal and the communications signals are frequency-multiplexed for transmission to the corresponding micro-cells 51.

Abstract: In an optical transmission apparatus including an external optical modulator for modulating an optical carrier from a light source with an electrical signal, bias voltage applied to the external optical modulator is accurately adapted to fluctuations in optimal bias voltage due to DC drift. A bias voltage control circuit controls bias voltage applied by a bias voltage applier to an external optical modulator so as to minimize an amount of second order distortion included in an optical signal from the external optical modulator and caused by non-linearity thereof.

Abstract: In optical transmission of a radio-frequency signal such as a microwave signal and millimeter-wave signal, a radio-frequency circuit for distortion compensation results in complex adjustment and very expensive. For betterment, the radio-frequency transmitter with the function of distortion compensation of the present invention takes the following structure.

Abstract: A NOx removal system for boilers in which the need for any special heat retention means or any warming means is eliminated. Ammonia jet nozzles 7 are disposed on a gas passage (5) of a boiler (1) or flue (6), and ammonia generating means (8) connected to the jet nozzles (7) is disposed within the flue (6).

Abstract: A method for controlling a NOx removal system in which reductant supply is adjusted according to combustion level in a boiler (1) in which the combustion level is controlled in multiple stages. For a decrease of the combustion level, the reductant supply is kept lower than a level corresponding to a changeover-target combustion level for a period of a set time from the changeover of the combustion level. Thus, when the reductant supply is changed over in response to a changeover of combustion level, the reductant can be prevented from flowing outside as it is unreacted.

Abstract: A signal including an RF signal and a code division multiple access signal is transmitted so that, in relation to both of the RF signal and the code division multiple access signal, a receiving end can obtain a signal having sufficiently larger power as compared with noise and with no distortion. In order to attain this object, a separation part separates the signal into the RF signal and the code division multiple access signal at a sending end. An amplification part amplifies the RF signal with an amplification factor related to its power. An amplification part amplifies the code division multiple access signal with an amplification factor related to its power. A combination part combines the amplified RF signal and the amplified code division multiple access signal with each other.

Abstract: The invention provides an ammonia generating apparatus which is high in efficiency of heat transfer and compact. The ammonia generating apparatus includes a urea water introducing part, a flow passage for urea water to flow therethrough, and heating means, wherein the flow passage is connected to the urea water introducing part, and the heating means heats urea water present within the flow passage.

Abstract: The invention provides a NOx removal system for use in a boiler for realizing further reduction in NOx. Loading means for loading a reducing agent is provided at the outlet of a gas passageway in the boiler body, and a NOx removal catalyst is provided downstream of the loading means.

Abstract: In an optical transmission apparatus including an external optical modulator for modulating an optical carrier from a light source with an electrical signal, bias voltage applied to the external optical modulator is accurately adapted to fluctuations in optimal bias voltage due to DC drift. A bias voltage control circuit 150 controls bias voltage applied by a bias voltage applier 105 to an external optical modulator 110 so as to minimize an amount of second order distortion included in an optical signal from the external optical modulator 110 and caused by non-linearity thereof.

Abstract: The method for producing an aluminum wheel rim comprises axially pressing a thin walled cylindrical aluminum or aluminum alloy material under the action of compressive stress acting thereon through tapered portions of a die and a punch cooperating therewith in a press machine so that the diameter of the material is enlarged so as to form the required configuration of the rim, while the wall thickness of the material is increased at positions where compressive stress is applied through the tapered portions of the die and the punch thereby increasing the mechanical strength of the material at positions where otherwise weakening tends to occur due to the thinning of the wall thickness of the material by the roll working thereof. In order to successfully carry out the method, it is preferred to select the ratio H/D of the height H of the material with respect to the inner diameter D thereof to be equal to or less than 1.