Abstract: A read method of a semiconductor memory device includes performing a read operation on target cells by using a first read voltage, terminating the read operation on the target cells if, as a result of the read operation on the target cells, error correction is feasible, performing a read operation on first cells next to the target cells along a first direction if, as a result of the read operation on the target cells, error correction is unfeasible, performing the read operation again on the target cells by selecting one of a plurality of read voltages in response to a result of the read operation on the first cells and by using the selected read voltage for reading data of the target cells, and terminating the read operation on the target cells if error correction is feasible.

Abstract: A programming method of a nonvolatile memory device includes inputting even data and odd data to be programmed into even memory cells coupled to even bit lines and odd memory cells coupled to odd bit lines, respectively, setting a sense signal as a first sense signal or a second sense signal having a lower voltage level than the first sense signal, based on odd data of odd memory cells adjacent to each of the even memory cells to be programmed, programming the even data into the even memory cells by supplying a program voltage, performing a program verify operation on each of the even memory cells in response to the set sense signal, and programming the odd data into the odd memory cells by supplying a program voltage.

Abstract: A frequency tunable filter comprises a housing having a plurality of walls therein defining a plurality of cavities; a cover mounted on the housing; a plurality of resonators contained in the cavities; at least one sliding member located between the cover and the resonators; and a plurality of metal tuning elements attached to a lower part of the sliding member, wherein frequency tuning is performed by sliding of the sliding member.

Abstract: A tunable filter for expanding tuning range includes: a housing, which has multiple cavities defined by partitions; a resonator contained in the cavity; at least one sliding member installed over the resonator; a main cover coupled to an upper portion of the housing; and at least one tuning element coupled to a lower portion of the sliding member and made of a metallic material. Tuning is accomplished by a sliding motion of the sliding member, and the resonator includes a cylindrical first conductor and a second conductor coupled to an upper portion of the cylindrical conductor, where a cross section of the second conductor is shaped as a circle with a portion removed such that an area of overlap between the tuning element and the second conductor is varied according to a sliding of the tuning element.

Abstract: A frequency-tunable filter using a sliding system is disclosed. The frequency-tunable filter includes: a housing, in which a multiple number of cavities are defined by partitions; a sub-cover, which is coupled to an upper portion of the housing and in which a guide groove is formed; at least one sliding member installed in the guide groove; a main cover coupled to an upper portion of the sub-cover; a resonator held in the cavity; and at least one tuning element coupled to a lower portion of the sliding member to be inserted inside the housing, where tuning is achieved by a sliding movement of the sliding member, and at least one first guide member is coupled to at least one side surface of the sliding member such that the first guide member guides a sliding movement by way of contact with the side surface of the guide groove.

Abstract: A frequency tunable filter comprises a housing having a plurality of walls therein defining a plurality of cavities; a cover mounted on the housing; a plurality of resonators contained in the cavities; at least one sliding member located between the cover and the resonators; and a plurality of metal tuning elements attached to a lower part of the sliding member, wherein frequency tuning is performed by sliding of the sliding member.

Abstract: Disclosed is a system and method for producing a sound having a certain frequency range to maintain laying hens in more stable and comfortable conditions. The system comprises a basic wave generator for generating a pair of first basic waves having the same phase and a pair of second basic waves having opposite phases, a relaxation wave generator for generating a pair of relaxation waves by combining the pair of first basic waves and the pair of second basic waves with time, a modulator for generating a pair of relaxation sounds by modulating the pair of relaxation waves with a sound wave having an audible frequency, and an audio output unit composed of two left and right parts such that stereo sound is outputted, for receiving the pair of relaxation sounds and outputting the pair of relaxation sounds to the left and right parts, respectively.

Abstract: A method for fabricating a semiconductor laser diode includes the steps of forming a double hetero structured semiconductor layer on a substrate, forming a dielectric layer on the double hetero structured semiconductor layer, selectively etching the dielectric layer to expose a portion of the double hetero structured semiconductor layer, selectively removing the exposed semiconductor layer using the dielectric layer as a mask by liquid phase etching, and re growing a semiconductor layer on the etched portion by liquid phase epitaxy.