Abstract: A computer system has a normal mode for performing its work in a normal and regular manner and a standby mode which progresses to a power saving mode after storing information about the state of the work in process in a memory.

Abstract: An adaptive modulation scheme relating to an RA problem for maximizing the transmission rates of all users for maximum transmission rates in an OFDMA system including some users requiring to use services at fixed data rates. The scheme proposes introduction of an adaptive modulation using linear programming into an existing scheme for a system including a single kind of users, thereby enabling simultaneous execution of the adaptive modulation for all users in a system including two kinds of users. Further, the invention proposes another scheme of sequentially allocating subchannels to the users when the fixed transmission rate has a sufficiently small value, in order to reduce the complexity.

Abstract: A disk drive including a tray on which a disk cartridge is mounted and is loaded into and unloaded from a main body; a guide formed on the tray; and an opening and closing member installed to be elastically connected to the guide. The opening and closing member has a second gear that rotates a rotating wheel by meshing with a first gear; and a first protrusion formed on one end of a second gear and to temporarily rotate the rotating wheel so that the first and second gears can mesh. The guide pushes the first protrusion during loading/unloading of the tray so that the first protrusion and the latch do not come in contact with each other.

Abstract: An optical disk player with improved opening and closing of a door, transport of a tray, and an improved pivoting structure of a chassis to pivot a turntable. The optical disk player includes: a body; a tray to move in and out of the body so as to transport an optical disk; a chassis installed to pivot inside the body; an optical pickup, which is installed to be able to move back and forth in the chassis, to record/reproduce information onto/from the optical disk that is rotatably placed on the turntable; a cover installed on a front of the body, the cover including: a door holder with an aperture through which the tray moves; a door to be able to slide along the door holder so as to open and close the aperture; and a cam driving device to activate the tray, to pivot the chassis, and to open and close the door by sliding.

Abstract: An optical disc includes a substrate having micro-embossments, in which flat portions referred to as lands, and track guides, referred to as hills, and which protrude from the surfaces of the flat portions are formed. A reflective layer is formed on the substrate, a dielectric layer is formed on the reflective layer, a recording layer is formed on the dielectric layer, and a protective layer is formed on the recording layer. Thus, the lands and hills on the substrate of the optical disc enable disc fabrication to more easily facilitate manufacturing of the optical disc. Accordingly, tracks of the disc can be narrowed, to thereby enhance a recording density of the optical disc.

Abstract: A disk drive including a tray and an opener. The tray includes a disk cartridge mounted thereon and is loaded into and unloaded from a main body. The opener is installed in the main body and elastically contacts a guide formed on the tray. The opener includes a second gear and a first protrusion. The second gear rotates a rotating wheel when in contact with a first gear. The first protrusion formed on a first end of the second gear temporarily rotates the rotating wheel so that the first and second gears can mesh. The guide has a first cam that moves the opener such that the first protrusion does not interfere with the latch when the tray is loaded/unloaded.

Abstract: In the ICI cancellation method for OFDM communication system, a receiver performs channel estimation using pilot subcarriers included in transmission signals transmitted from at least one transmitter. The transmitter generates the transmission signal in which pilot subcarriers and data subcarriers are regularly arranged, performs preceding on the transmission signal, modulates the pre-coded transmission signal into an OFDM symbol, and transmits the OFDM symbol. The receiver receives the OFDM symbol; demodulates the OFDM symbol, detects the pilot subcarriers from a demodulated signal, estimates channels using the pilot subcarriers, and restores the transmission signal using the estimated channels.

Abstract: A communication method in an FH-OFDM communication system having a plurality of BSs is provided. A predetermined number of pilot pattern groups are generated, each pilot pattern group having a predetermined number of different pilot patterns for pilot transmission. The pilot patterns in each of the pilot pattern groups are mapped to different FH sequence sets. The pilot patterns and FH sequence sets are assigned to the BSs so that MSs within the service areas of the BSs can identify the BSs.

Abstract: A code acquisition device securing reliable code acquisition and reducing a time required for a code acquisition procedure. In the device, a sampler samples an input signal, and a searcher continuously searches for a spreading code used for the sampled signal until the phase of the spreading code is acquired. A verifier verifies whether the phase of the spreading code used for the sampled signal is acquired, according to the search result of the searcher. The searcher initializes and restart the verifier whenever the phase of the spreading code is searched.

Abstract: An optical disc includes a substrate having micro-embossments, in which flat portions referred to as lands, and track guides, referred to as hills, and which protrude from the surfaces of the flat portions are formed. A reflective layer is formed on the substrate, a dielectric layer is formed on the reflective layer, a recording layer is formed on the dielectric layer, and a protective layer is formed on the recording layer. Thus, the lands and hills on the substrate of the optical disc enable disc fabrication to more easily facilitate manufacturing of the optical disc. Accordingly, tracks of the disc can be narrowed, to thereby enhance a recording density of the optical disc.

Abstract: An actuator for an optical pickup having a base on which a holder is fixed, a bobbin, a support member, and a magnetic circuit. Pluralities of installation holes are formed in the bobbin such that a plurality of objective lenses to record and/or reproduce optical discs having different recording densities are installed at different heights. The support member has one end coupled to the bobbin and the other end coupled to the holder movably supports the bobbin. The magnetic circuit drives the bobbin in focusing and tracking directions. The magnetic circuit is divided into a first magnetic circuit to drive the objective lenses in the focusing direction, and a second magnetic circuit to drive the objective lenses in the tracking direction, thereby reducing the weight of a moving portion.

Abstract: An actuator for an optical pickup having a base on which a holder is fixed, a bobbin, a support member, and a magnetic circuit. A plurality of installation holes are formed in the bobbin such that a plurality of objective lenses to record and/or reproduce optical discs having different recording densities are installed at different heights. The support member has one end coupled to the bobbin and the other end coupled to the holder movably supports the bobbin. The magnetic circuit drives the bobbin in focusing and tracking directions. The magnetic circuit is divided into a first magnetic circuit to drive the objective lenses in the focusing direction, and a second magnetic circuit to drive the objective lenses in the tracking direction, thereby reducing the weight of a moving portion.

Abstract: A disk cartridge which includes a case having an upper wall, a lower wall, and a sidewall, which form an inner receiving space in which a disk is inserted, an opening formed in at least one of the upper wall and lower wall of the case to allow a recording/reproducing unit of a disk drive to access the disk therethrough, and an inlet hole formed at the sidewall of the case to allow the disk to be inserted into and withdrawn from the case therethrough.

Abstract: Disclosed is an adaptive receiving MIMO (multi input and multi output) system and method which decides a symbol detecting order so as to estimate the symbol having the minimum summation of weights of least square errors at the time of estimating the symbol for respective equalizers provided in parallel by the number of transmit antennas, and updates filter tap coefficients based on the RLS algorithm according to the detecting orders. Therefore, the filter tap coefficients are directly updated without tracking channels in the time-varying channel environment, and accordingly, detection performance very similar to those of the channel tracking and conventional V-BLAST scheme is provided with reduced complexity.

Abstract: A disk clamping apparatus for a disk player includes a turntable for receiving a disk, a disk clamper which clamps the disk placed on the turntable, and first and second magnetic bodies which are mounted in the corresponding turntable and the disk clamper and provide a clamping force to the disk by acting a reciprocal magnetic force on the turntable and the disk clamper. The first and second magnetic bodies are opposite to each other and partially overlap each other. In the disk clamping apparatus having the above structure, the variation in a clamping force caused by the variation in thickness of disks, received by the disk clamping apparatus, is very small. Accordingly, clamping and de-clamping of the disks having different thickness can be smoothly performed.

Abstract: An optical pickup apparatus having compatibility with a recodable compact disk (CD-R) and a digital video disk (DVD), which uses a wavelength of one of a first light beam and a second light beam according to the recording medium to be used. In the optical pickup apparatus, laser light sources emit a first light beam having a relatively shorter wavelength for the. DVD and a second light beam having a longer wavelength for the CD-R, respectively. An objective lens has a predetermined focal length in accordance with the position of an information recording surface in the DVD. An optical path control unit controls the path of light beams so that the light beam emitted from one of the laser light sources is directed to the objective lens and the light output from the objective lens is directed to the optical detection unit.

Abstract: A disk cartridge includes a case which contains a disk, and a shutter which opens/closes at least one opening formed in the case. The shutter is configured to be foldable around upper and lower surfaces of the case, and slides on the upper and lower surfaces of the case to open/close the opening. Since the shutter opens/closes the opening while being folded around the upper and lower surfaces of the case, a movable distance of the shutter for opening/closing the opening can be fully accommodated even though the size of the disk cartridge is reduced. In addition, applying the configuration of the shutter to a double-sided disk cartridge prevents an inflow of dust from entering into the double-sided disk cartridge since the shutter closes an opening, which is not in use, during a recording/reproducing operation.

Abstract: An apparatus for adaptively modulating/demodulating signals in a multi-input multi-output (MIMO) system having a layered time-space architecture detector and a method thereof is disclosed. The apparatus includes: a bit and power allocation information calculator for deciding an equivalent channel gain in a reverse order of Vertical-Bell laboratories Space Time (V-BLAST) based on MIMO channel information feedbacked from a receiver and determining the number of bits and transmission power to be transmitted to each transmitting antenna by using the equivalent channel gain; and adaptive modulation means for modulating signal of each layer with corresponding modulation method based on the determined number of bits and transmitting power, controlling the transmitting power and transmitting the adaptively modulated signal through each transmitting antenna.

Abstract: An actuator for an optical pickup includes a base, a holder fixed to the base, a moving portion on which an objective lens for focusing incident light onto a disc and a liquid crystal panel for correcting spherical aberration are mounted, a magnetic driving portion which drives the moving portion in a radial direction and in a focusing direction relative to the disc, and a connection section which includes a first connection part which serves as an electrical connection path of a signal used to drive the magnetic driving portion and has at least four wires, and a second connection part electrically independent of the first connection part, which serves as an electrical connection path of a signal used to drive the liquid crystal panel, and has wires, and which supports the moving portion to be movable with respect to the holder.

Abstract: A method for adaptively allocating resource can be simply implemented for reducing degradation of performance by effectively separating operations of sub-channel and time slot allocation and selection of modulation method and sequentially processing each of operations. A method for adaptively allocating resource in a communication system to sequentially process sub-carrier/time slot allocation and modulation method selection efficiently includes the step of a) computing average channel gains of sub-carriers/time slots for each user by using channel gains of sub-carriers/time slots for each user; b) computing average numbers of bits for each user by using required data rates and average channel gains of sub-carriers/time slots for each user; c) computing the number of sub-carriers/time slots allocated to each user and allocating the sub-carriers/time slots to each user; and d) selecting a modulation method with respect to each sub-carrier/time slot.