Abstract: In a voltage controlled oscillator, a voltage controlled oscillating part includes a resonance circuit, a differential amplifying circuit and an active load. The resonance circuit generates a resonance signal. The differential amplifying circuit feeds back the resonance signal from the resonance circuit and outputs two oscillation signals having a phase difference of 180°. The active load controls gain of the oscillation signals generated in the differential amplifying circuit. Further, an automatic amplitude controlling part converts the oscillation signals into a direct voltage and compares the direct voltage with a preset reference voltage to output a control voltage for determining a resistance value of the active load. The invention effectively adjusts amplitude of the oscillation signals outputted and reduces phase noise resulting from noise components induced by current source in case of switching of the differential amplitude circuit.

Abstract: The invention provides a low divide ratio programmable frequency divider of a fractional-N type applied to a digital MOPLL tuner and a method thereof. In the invention, a divide ratio assigner assigns divide data as a main divide ratio and a pulse swallow value according to a first or a second dividing operation mode in response to a mode selection signal. A prescaler operates on the first or second divide operation mode in response to the mode selection signal. Also, a main counter divides a frequency from the prescaler by the main divide ratio. Further, a pulse swallow counter counts a clock of the main counter while outputting a pulse swallow signal to the prescaler. The pulse swallow signal has a swallow level if a counting value corresponds to the pulse swallow value, and a non-swallow level if the counting value does not correspond to the pulse swallow value.

Abstract: A heat pump air conditioner includes an outdoor unit for heating use only for supplementing heating capacity when additional heating capacity must be provided to the heating capacity of an outdoor unit for heating and cooling in a heating mode. Since the outdoor unit for heating use only is installed independent from the outdoor units for heating and cooling use, such that the outdoor unit for heating use only can supplement the heating capacity only when the additional heating capacity is required in addition to the heating capacity of the outdoor units for heating and cooling use in the heating mode, in order to correspond to the heating load in cold climes, there is no need to install an outdoor unit having larger heating capacity than the required heating capacity. Thus, costs for installation and management are reduced.

Abstract: Disclosed herein is a method for operating an air conditioner which is capable of achieving the effective operation of a plurality of indoor units. The method comprises the steps of: a) receiving operating state information of the indoor units connected to one outdoor unit; b) determining whether or not the amount of refrigerant to be distributed into the indoor units needs to be regulated, based on the operating state information of the indoor units; and c) regulating the amount of the refrigerant to be distributed into the indoor units.

Abstract: An indoor unit of an air conditioner is disclosed. The air conditioner is an apparatus that cools or heats an indoor space by circulating refrigerant in one direction or another. The indoor unit of the air conditioner comprises a case spaced apart from the ceiling of a room by a predetermined distance, an indoor heat exchanger provided in the case to heat or cool the room, and a fan and fan motor provided in the case to suction and discharge air.

Abstract: A multi-unit air conditioner is disclosed. The multi-unit air conditioner includes an outdoor unit comprising at least two compressors, a plurality of indoor units connected to the outdoor unit, a plurality of oil separators each connected to an associated one of the compressors to separate oil from a refrigerant discharged from the associated compressor, an oil storage for storing the oil separated from each oil separator, a plurality of oil supplying tubes each having one end connected to the oil storage, and the other end connected to an associated one of the compressors to supply the oil stored in the oil storage to the associated compressor, and adjusters each arranged at an associated one of the oil supplying tubes to adjust an amount of oil supplied from the oil storage to an associated one of the compressors in accordance with an oil storage state of the associated compressor.

Abstract: A system and method for transmitting data by a base station in a multiple access communication system including a plurality of sub-channels, each of which includes a predetermined number of sub-carrier bands, the sub-carrier bands being divided from an entire frequency band. The method includes the steps of: dividing input data streams in a unit of the sub-channels corresponding to each terminal into a plurality of data sequences based on a predetermined length; spreading each of the data sequences by a distinct spread spectrum code, respectively; summing and parallel-converting the spread data; hopping each frequency of the parallel-converted data in the unit of the sub-channels based on a frequency hopping pattern allocated to each of the terminals in advance; performing an inverse fast Fourier transform with respect to the hopped parallel-converted data; and transmitting the transformed data.

Abstract: A method for forming a groove-shaped nanopattern, which involves the steps of forming a thin film of supramolecules on a substrate, inducing the self-assembly of the supramolecules by annealing to form regular structures, and applying UV to the formed regular structures of supramolecules. A method for fabricating a CNT nanoarray is also described, which includes the step of forming a regular metal catalyst array for synthesizing CNT using a formed nanopattern of supramolecules as a mask, and then synthesizing CNT vertically. In another aspect, a method is described for fabricating a CNT-bionanoarray, which involves attaching a bioreceptor to the fabricated CNT array.

Abstract: The present invention relates to a method and apparatus for detecting STBC-OFDM signals in time-variant channels. The method includes a step of demodulating STBC-OFDM modulation signals into OFDM reception symbols using Fast Fourier Transform (FFT); a step of estimating a frequency response for each sub-channel; an STBC decoding step of calculating decision variables determining the A transmit data symbols that are transmitted during the B OFDM symbol periods for each sub-channel; and a step of determining the transmit data symbols based on the decision variables calculated at the STBC decoding step. In this case, the decision variables are calculated using a linear equation that allows a squared Euclidean distance from OFDM reception symbols, which are demodulated during the B symbol periods, to have a local minimum for each decision variable when the STBC encoding and the frequency responses estimated during the B OFDM symbol periods are applied.

Abstract: The present invention relates to mass production method for three-dimensional micro structure and especially to the mass production method for three-dimensional metal micro structure having high aspect ratio. According to the present invention, the manufacturing of the three-dimensional micro structure having high aspect ratio is possible, which was impossible with the prior art of MEMS or LIGA. Especially, micro structure with complex shape can be obtained through dividing into layers and depositing the layers. Micro structure with any shape can be obtained with the method according to the present invention.