Abstract: Disclosed herein are a method for providing a composite image based on optical transparency and an apparatus for the same. The method includes supplying first light of a first light source for projecting a virtual image and second light of a second light source for tracking eye gaze of a user to multiple point lights based on an optical waveguide; adjusting the degree of light concentration of any one of the first light and the second light based on a micro-lens array and outputting the first light or the second light, of which the degree of light concentration is adjusted; tracking the eye gaze of the user by collecting the second light reflected from the pupil of the user based on the optical waveguide; and combining an external image with the virtual image based on the tracked eye gaze and providing the combined image to the user.

Abstract: Disclosed is a self-calibration method and apparatus for an array antenna system. According to an embodiment of the present disclosure, a correction method of an array antenna system includes: deriving, at a first time, a correction factor Ri,j for a path connecting an i-th (i is an integer equal to or greater than one and equal to or less than m) transmission antenna and a j-th (j is an integer equal to or greater than one and equal to or less than n) reception antenna; deriving, at a second time, a calibration factor {circumflex over (Q)}i,j for the path connecting the i-th transmission antenna and the j-th reception antenna; and performing, based on the {circumflex over (Q)}i,j, calibration on the path connecting the i-th transmission antenna and the j-th reception antenna.

Abstract: The present invention relates to a device and a method for simulating 3D printing and more particularly, to a simulation technology which is able for a producer or a user to predict and correct a 3D model through previews shown when the 3D model displayed in a monitor is outputted by a 3D printer.

Abstract: Provided is a method of transmitting and receiving a frame for a multi-user multiple-input and multiple-output (MU-MIMO) communication in an access point (AP), the method including transmitting, to each of a plurality of stations (STAs), an uplink multi-user request (UL MU request) frame requesting transmission of a data frame, and receiving, from each of the plurality of STAs, the data frame during an identical period of time based on an identical reception intensity, wherein the UL MU request frame includes at least one of information on a transmission time of the data frame and information on a reception intensity of the data frame in the AP.

Abstract: Provided is a method and apparatus for efficient aggregation scheduling in a wireless local area network (WLAN) system, the apparatus including a delay setting unit to set a required delay time for each access category (AC), a storing unit to store a traffic identification (TID) of a packet in a queue of a corresponding AC when the packet arrives, a delay time calculator to calculate a maximum delay time predicted when the packet arriving at the queue is configured to be an A-MPDU and the configured A-MPDU is transmitted, and an A-MPDU configuring unit to compare the calculated maximum delay time and the required delay time, and configure a corresponding A-MPDU when the calculated maximum delay time is greater than the required delay time.

Abstract: A device to device (D2D) communication method based on a partial device control is disclosed. According to the present invention, the D2D communication method and, particularly, to a partial device control method for D2D communication a relates to, and provides a D2D resource allocation and release method, a D2D HARQ process operating method, a link adaptation method comprising D2D link power control and adaptive modulation and coding (AMC), a D2D control information signaling method, a CSI reporting method for D2D communication, and contents of a CSI report. The present invention can enhance the advantages of and compensate for the disadvantages of both methods through the combination of a base station control a base station control type D2D communication method and a device control type D2D communication method.

Abstract: A burst-mode optical amplification apparatus and method is provided. The burst-mode optical amplification apparatus includes a gain saturation signal generator configured to generate a gain saturation signal for gain stabilization based on an incoming input optical signal; a wavelength multiplexer configured to wavelength multiplex the incoming input optical signal and the gain saturation signal; and an optical amplifier configured to amplify both the wavelength-multiplexed input optical signal and the wavelength-multiplexed gain saturation signal. The apparatus may further include a time delay module configured to synchronize the input optical signal and the gain saturation signal by delaying the transmission time of the input optical signal, taking into consideration the processing time needed by the gain saturation signal generator to generate the gain saturation signal.

Abstract: A protection switching method and apparatus based on a memory control in a packet transport system are provided. The protection switching method may perform hardware-based protection switching based on a type of path failures that occur. The protection switching method may perform protection switching for each of an Automatic Protection Switching (APS) frame or a Loss of Continuity (LoC)/Clear Loss of Continuity (CLoC) message received via an interface unit from a packet processor, a LoC/CLoC message received via a local bus interface from a host processor, an APS frame generation command input via the local bus interface from protection software (SW) of the host processor, and an APS frame generation command input via another interface unit from the protection SW.

Abstract: Disclosed are channel management methods in a multicarrier structure in a mobile communication system. Uplink (UL) and downlink (DL) channel management methods in a carrier aggregation environment are used as the channel management methods. In DL, a base station determines a component carrier (CC) of an unstable radio channel state, stops data retransmission by the CC, and notifies a terminal of retransmission stop. In UL, the base station determines a CC of an unstable radio channel state and instructs the terminal to stop data retransmission by the CC, and the terminal stops the data retransmission and initializes a retransmission buffer.

Abstract: A method and apparatus for scanning a channel in a wireless local area network (WLAN) system may be disclosed including, extracting at least one target channel from among a plurality of channels present in at least one frequency band, based on channel scanning record information, generating a basic service set (BSS) existing information element (IE) including at least one BSS existing channel bitmap indicating information associated with a channel in which at least one access point (AP) exists, based on channel information received from at least one neighboring station (STA), determining a scanning rank of the at least one target channel, using the BSS existing channel IE, and identifying a target AP through scanning the at least one target channel, based on the scanning rank.

Abstract: There is provided a high frequency transceiver appropriate for ultra low power and high frequency characteristics. The high frequency transmitting device includes a voltage controlled oscillator configured to provide an oscillation signal; and a power amplifier configured to multiply the oscillation signal by an integer to generate a carrier signal, mix the carrier signal and a baseband signal to generate a mixed signal, and amplify power of the mixed signal.

Abstract: Disclosed are a white box encryption apparatus and method. The white box encryption method includes performing an encryption operation using a plurality of white box encryption tables for each of a plurality of rounds, and mixing arrangement of result tables output for each round.

Abstract: An IP packet forwarding server forwards an IP data packet between a user terminal and a machine-type communications (MTC) device allocated with a private internet protocol (IP). Such an IP packet forwarding server allocates a call identifier for connection between the user terminal and the MTC device, sets up a packet call to the MTC device and the user terminal using the call identifier, obtains packet forwarding information while setting up the packet call to the MTC device and the user terminal, and forwards an IP data packet between the MTC device and the user terminal using the packet forwarding information.

Abstract: Provided are a method and apparatus for evaluating the effectiveness of a test case used for a program test on the basis of error detection capability. The method includes: receiving a target program used for evaluating the effectiveness of the test case; generating an error program by inputting errors to the target program; detecting the errors by executing the test case on the generated error program; and calculating evaluation points of the test case using a ratio of the number of the detected errors to the number of the input errors. Thus, the capability of the test case used for a program test to detect errors can be evaluated.

Abstract: Provided is an apparatus for generating a ranging binary code sequence at a high-speed, and a method thereof. The apparatus includes: an initial register value generator for generating initial register values of minimum valid ranging codes; a storage for storing the generated initial register values of the valid ranging codes(?K, where K is the ranging value transmitted by base station); a binary code sequence generator for generating a binary code sequence of a corresponding ranging code; and a procedure for incrementally updating the initial register values as receiving the new ranging code from base station.

Abstract: A method for controlling a security channel for reducing system load by extending the use period of a security association key is provided. In this method, an upper bit initial value of an initialization vector of an encryption algorithm and a using range thereof are shared between a transmitting side and a receiving side when a security channel is created. Then, a secure association is created between a transmitting side and a receiving side by setting an association number, a next packet number which is a lower bit value of an initialization vector, and a secure association key. Afterward, a packet number is modified whenever a frame is transmitted until all of packet numbers are used. When all packet numbers are used, the upper bit value of the initialization vector changes.

Abstract: An apparatus for moving the center of gravity of a robot, and a system and method using the apparatus are provided. The apparatus includes a weight conveyor with a conveyed weight weighing a predetermined amount and disposed within the main body of the robot. The conveyed weight is conveyed in a predetermined direction to move the center of gravity of the robot, thus allowing a non-driven caster of the robot to surmount obstacles in its path and not become stuck while the robot is moving.

Abstract: Disclosed is an encoding/decoding apparatus of a HARQ system using LDPC codes. A first LDPC code encoding apparatus encodes input information data and transmits the encoded data to the decoding apparatus. An interleaver interleaves the input information data. A second LDPC code encoder in parallel with the first LDPC code encoder performs LDPC code encoding on an output of the interleaver so as to transmit it to the decoding apparatus. The first LDPC code encoder transmits an output signal to the decoding apparatus at odd numbered retransmissions in response to a retransmission request from the decoding apparatus, and the second LDPC code encoder transmits an output signal to the decoding apparatus at even numbered retransmissions in response to the retransmission request from the decoding apparatus.

Abstract: A method for file deletion and recovery against system failures in a database management system comprising steps of deleting files listed in a pending action list during a transaction commit process, writing a non-atomic file deletion as an atomic operation into a log and recovering uncompleted file deletion during restart recovery by using the log is disclosed. When system failures occur during file deletion in a database management system, resources of which releasing is interrupted by failures are released perfectly through recovery step, so it is advantageous in that coherency of data is maintained and efficiency of storage device arises.

Abstract: A telephone system is provided with a receiver equipped to enable a hearing-impair person to receive a telephone call through bone-conduction and air-conduction hearing.