Abstract: A drum-type washing machine employs a gasket water draining hose to enable used water to be discharged via the drainpipe, immediately following a washing or rinsing step. The drum-type washing machine includes a cabinet having a door; a tub for containing water, the tub having an entrance corresponding to the door of the cabinet; a gasket, connecting the door of the cabinet to the entrance of the tub, to prevent water contained in the tub from leaking outside the tub, the gasket having a first orifice provided at a bottom point thereof; a drainpipe, communicating with the tub, to discharge water contained in the tub, the drainpipe having a second orifice provided at one side thereof; and a water draining hose, communicating the first orifice with the second orifice, to discharge water via the drainpipe.

Abstract: Provided is a dispersion-shifted fiber for an optical parametric amplifier. The dispersion-shifted fiber is a silica-based optical fiber and has a large nonlinear coefficient and a small effective area. The dispersion-shifted fiber also reduces a bending loss and a splice loss due to a mode field diameter difference between it and a conventional single mode fiber. For this, the dispersion-shifted fiber comprises a rectangular core with a very small radius and a high refractive index, a depressed inner clad, and an outer clad with a ring. The core and/or the inner clad are/is doped with a heavy metal.

Abstract: Provided are a Raman amplifier and a Raman pumping method. A light source unit outputs a pumping light having a wavelength that periodically changes. A light intensity control unit varies a light intensity of the pumping light using the pumping light to improve the gain flatness of a Raman gain. A control unit directs the light intensity control unit to control the light intensity of the pumping light in synchronization with changes in the wavelength of the pumping light.

Abstract: A fuel cell system is disclosed. The fuel cell system includes a stack unit including a fuel electrode and an air electrode and generating electricity by an electrochemical reaction between hydrogen and oxygen; a fuel supply unit supplying hydrogen to the fuel electrode of the stack unit; an air supply unit supplying the air to the air electrode of the stack unit; and a residual gas storage unit storing residual hydrogen exhausted from the stack unit or the fuel supply unit and then supplying the residual hydrogen to the stack unit again or to another system requiring hydrogen. The residual gas storage unit of the fuel cell system allows residual hydrogen to re-supplied to the stack unit if necessary, so that a waste of raw materials for generating hydrogen can be reduced and thus a cost can be reduced.

Abstract: A long-wavelength band (L-band) optical amplifier capable of maintaining a gain constant, thereby providing a stable optical output even when an optical power or a wavelength of a signal input thereto changes. The optical amplifier includes an amplifier which amplifies an input signal, and an amplified spontaneous emission (ASE) reflector which reflects backward ASE generated by the amplifier so that the backward ASE is fed back to the amplifier.

Abstract: The present invention discloses an apparatus for suppressing stimulated Brillouin scattering and the method thereof that a threshold fiber input power is raised in order to prevent loss of an inputted light by stimulated Brillouin scattering being generated in a case that a signal having a strong intensity is inputted to the optical fiber and so a light signal having more strong intensity can be inputted to the optical fiber. The apparatus for suppressing the SBS includes a plurality of first transmission unit, each of which has a wavelength separation, for transmitting information signals through a signal channel; and a second transmission unit for generating and transmitting a supervisory signal of which a modulation frequency and an intensity generates a phase modulation to the plurality of information signals, through a supervisory channel.

Abstract: The present invention provides an optical transponder with an add/drop operation function of optical channels, which combines operating functions of adding and dropping type optical transponders in accordance with mounting of a digital wrapper to simultaneously process two optical channels. The optical transponder receives an optical signal, converts the optical signal into electrical signal, adds maintenance information, monitoring information, and error correction information to each of the converted signals, and detects the maintenance information, monitoring information, and errors contained in each of the signals. Furthermore The optical transponder corrects the detected errors, and transmits the signals having the maintenance information, monitoring information, and error correction information and the signals of which errors are corrected.

Abstract: Provided are an optical fiber amplification method and apparatus for controlling a gain. Initial values including target gains of first and second amplifications for an optical amplifier amplifying the input light signal are set. Power of the input light signal is measured and the power of first and second backward pump lights proceeding in the opposite direction to the input light signal is controlled based on the measured power. The input light signal is firstly amplified and a first amplification gain of the amplified light signal is calculated. Power of a first forward pump light proceeding in the same direction as the input light signal is controlled so that the first amplification gain can be substantially equal to the target gain of the first amplification. The firstly amplified light signal is secondly amplified and a second amplification gain with respect to the input light signal is calculated.

Abstract: The present invention provides an apparatus and method for compensating for the variation of a gain spectrum attributable to the temperature variation of a fiber amplifier, and a long-wavelength band dispersion-compensating hybrid amplifier equipped with the gain spectrum compensating apparatus. The apparatus includes a DCF located between a first amplification stage and a second amplification stage to compensate for dispersion of an optical signal output from the first amplification stage and perform Raman amplification of the optical signal using input pumping light; at least one pumping light provision means for providing forward or backward pumping light to the DCF; first and second temperature detection means for detecting temperature variations of the first and second amplification stages, respectively; and control means for controlling intensity of the pumping light of the pumping light provision means according to the detected temperature variations.

Abstract: Provided are a Raman amplifier and a Raman pumping method. A light source unit outputs a pumping light having a wavelength that periodically changes. A light intensity control unit varies a light intensity of the pumping light using the pumping light to improve the gain flatness of a Raman gain. A control unit directs the light intensity control unit to control the light intensity of the pumping light in synchronization with changes in the wavelength of the pumping light.

Abstract: A low-noise optical fiber amplifier for performing a long-distance optical transmission in a wavelength division multiplexing optical transmission apparatus is provided. This amplifier includes a first optical fiber amplifier having a pre-stage optical fiber, and a first coupler for supplying pump light to the pre-stage optical fiber; a dispersion compensating Raman amplifier (DCRA) connected to the first optical fiber amplifier and having a dispersion compensating optical fiber (DCF) that compensates for the dispersion accumulated in an optical line and generates a Raman gain, and a second coupler for supplying Raman pump light onto the DCF; and a second optical fiber amplifier connected to the DCRA, and including a post-stage optical fiber and a third coupler for supplying pump light onto the post-stage optical fiber. Accordingly, this optical fiber amplifier is used for terrestrial WDM optical transmission, and thus has remarkably low noise figure compared to the existing optical amplifiers.

Abstract: Optical fiber amplifier with wide input power dynamic range is employed to make a first gain block and an optical fiber pumped by Raman pump have opposite spectral gain profiles each other, thereby obtaining flat output gain profile. The optical fiber amplifier includes: a first and a second gain blocks, wherein each gain block has a gain medium and at least one optical pump; an optical fiber disposed between the first and the second gain blocks; a Raman pump for generating a pumping light; and a coupling means for coupling the pumping light to the optical fiber.

Abstract: The present invention provides an optical transponder with an add/drop operation function of optical channels, which combines operating functions of adding and dropping type optical transponders in accordance with mounting of a digital wrapper to simultaneously process two optical channels. The optical transponder receives an optical signal, converts the optical signal into electrical signal, adds maintenance information, monitoring information, and error correction information to each of the converted signals, and detects the maintenance information, monitoring information, and errors contained in each of the signals. Furthermore The optical transponder corrects the detected errors, and transmits the signals having the maintenance information, monitoring information, and error correction information and the signals of which errors are corrected.

Abstract: A method of controlling a combined washing and drying machine is provided, which decreases the time required for completing the overall process from washing to drying. The method includes steps of inputting an operational command; performing washing and rinsing steps according to the operational command; simultaneously performing a dewatering step and a first drying step after completion of the watering and rinsing steps; and performing a second drying step after completion of the dewatering step. The first drying step may include the driving of a pump, a fan, a heater, and a drum motor, while the second drying step may include the driving of a supply valve in addition to the pump, fan, heater, and drum motor.

Abstract: A method of controlling a drum-type washing machine facilitates the removal of laundry from the drum after the completion of a wash cycle, by controlling the rotational speed/direction of a drum motor so that a force is applied to the drum, thereby separating the laundry from the inner surface of the drum, which becomes adhered thereto during a dewatering step. The method includes steps performing a wash cycle by respectively completing washing, rinsing, and dewatering steps according to a wash course; controlling the driving of the motor, after completion of the dewatering step, to apply a force to the drum; stopping the driving of the motor to allow the motor to freewheel and slow to a stop; and detecting a rotational speed of the motor as the motor freewheels.

Abstract: A drum-type washing machine employs a gasket water draining hose to enable used water to be discharged via the drainpipe, immediately following a washing or rinsing step. The drum-type washing machine includes a cabinet having a door; a tub for containing water, the tub having an entrance corresponding to the door of the cabinet; a gasket, connecting the door of the cabinet to the entrance of the tub, to prevent water contained in the tub from leaking outside the tub, the gasket having a first orifice provided at a bottom point thereof, a drainpipe, communicating with the tub, to discharge water contained in the tub, the drainpipe having a second orifice provided at one side thereof; and a water draining hose, communicating the first orifice with the second orifice, to discharge water via the drainpipe.

Abstract: A tub assembly in a drum-type washing machine includes a tub body having a cylindrical shape forming front and rear edge portions; a ring-type tub cover coupled with the front edge portion of the tub body; a tub back, coupled with the rear edge portion of the tub body, comprised of an outer circumference wall rising vertically to a predetermined height with respect to an outer circumference of a circular panel forming a recessed space, the outer circumference wall in tight contact with the rear edge portion of the tub body; and a motor assembly loaded at the recessed space. The tub assembly enables a reduction in tub size and weight, by devising a construction that obviates the need for a bracket for fixing a bearing housing to a tub back and this minimizing a rearward protrusion of the bearing housing and tub back.

Abstract: An optical channel power equalizer for equalizing the per-channel power levels of a multi-channel optical signal is provided. The channel power equalizer includes an optical spectrum measurement unit that extracts a portion of the amplified optical signal and measures the per-channel power levels of the extracted optical signal; a controller that compares the measured power levels with a predetermined reference value, and determines to output the degrees of attenuation per channel based on differences between the measured per-channel power levels and the reference value; and a per-channel optical attenuation unit that attenuates the per-channel power levels of a plurality of input optical signals based on the degrees of attenuation and outputs the attenuated optical signals as the plurality of channels.

Abstract: A control device for controlling an electro-optic modulator which receives an optical input signal, modulates the optical input signal with an electrical input signal and a bias voltage signal, and outputs the modulated optical signal is provided. The control device includes: a light source for providing the optical input signal used for the optical modulation to the electro-optic modulator; an optical input measuring unit for measuring the intensity of the optical input signal outputted by the light source; an optical output measuring unit for measuring the intensity of the optical output signal outputted by the electro-optic modulator; and a controller for adjusting the bias voltage signal and the gain of the electrical input signal depending on the intensity of the optical input signal and the optical output signal measured respectively by the optical input measuring unit and the optical output measuring unit.

Abstract: Provided are an optical fiber amplification method and apparatus for controlling a gain. Initial values including target gains of first and second amplifications for an optical amplifier amplifying the input light signal are set. Power of the input light signal is measured and the power of first and second backward pump lights proceeding in the opposite direction to the input light signal is controlled based on the measured power. The input light signal is firstly amplified and a first amplification gain of the amplified light signal is calculated. Power of a first forward pump light proceeding in the same direction as the input light signal is controlled so that the first amplification gain can be substantially equal to the target gain of the first amplification. The firstly amplified light signal is secondly amplified and a second amplification gain with respect to the input light signal is calculated.