Abstract: A network alignment method comprises the steps of: receiving two networks as inputs and performing a neural network operation respectively, vectorizing a plurality of nodes of each of the two networks; calculating a dual-perception similarity based on an embedding similarity between the vectorized nodes of each of the two networks, and a Tversky similarity representing a ratio of the number of previously aligned nodes included in a neighboring node to the normalized number of neighboring nodes of each combined node when configuring a node pair by combining nodes that are not aligned in the two networks; and selecting node pairs to be aligned among a plurality of nodes of the two networks based on the dual-perception similarity, thereby partially aligning the two networks so that the number of node pairs aligned in the two networks gradually increases according to the dual-perception similarity updated according to the two partially aligned networks.

Abstract: A recommendation apparatus separately extracts a positive graph and a negative graph representing the user's preference and non-preference for each item from the bipartite graph representing the relationship between users and items obtained using evaluation data, and vectorizes a plurality of nodes corresponding to users and items based on each of the extracted positive graph and negative graph and embeds them in a common virtual embedding space to recommend items that the user would prefer by considering not only preferences but also non-preferences of similar users for items.

Abstract: A device for completing a social network using an artificial neural network includes: a neural network unit configured to receive a target network having unrevealed missing nodes as input, infer the connections of the missing nodes with a neural network, and output multiple candidate complete networks according to various node sequences; and a selection unit configured to select one of the candidate complete networks outputted by the neural network unit, where the neural network unit outputs the candidate complete networks by using weights of a graph-generating neural network that has learned graph structures of reference networks having attributes similar to those of the target network, and the selection unit uses connection probability vectors obtained from the learned graph-generating neural network to select the candidate complete network probabilistically having a structure closest to that of the target network based on the connection probability vectors.

Abstract: A method and device for completing a social network using an artificial neural network are disclosed. The disclosed device includes: a neural network unit configured to receive a target network having unrevealed missing nodes as input, infer the connections of the missing nodes with a neural network, and output multiple candidate complete networks according to various node sequences; and a selection unit configured to select one of the candidate complete networks outputted by the neural network unit, where the neural network unit outputs the candidate complete networks by using weights of a graph-generating neural network that has learned graph structures of reference networks having attributes similar to those of the target network, and the selection unit uses connection probability vectors obtained from the learned graph-generating neural network to select the candidate complete network probabilistically having a structure closest to that of the target network based on the connection probability vectors.

Abstract: A communication system configured to send data using an interference alignment scheme is disclosed herein. The disclosed communication system includes an MS and a BS. The disclosed BS sends data using a transmission beamforming matrix that minimizes intra-cell interference. The disclosed MS receives the data using a reception beamforming matrix that minimizes inter-cell interference. The BS sends information about a reference beamforming matrix to the MS, and sends a pilot signal to the MS using the reference beamforming matrix. The MS estimates an effective channel using the reference beamforming matrix, and calculates the intensity of an interference signal from an interference BS.

Abstract: A communication system configured to send data using an interference alignment scheme is disclosed herein. The disclosed communication system includes an MS and a BS. The disclosed BS sends data using a transmission beamforming matrix that minimizes intra-cell interference. The disclosed MS receives the data using a reception beamforming matrix that minimizes inter-cell interference. The BS sends information about a reference beamforming matrix to the MS, and sends a pilot signal to the MS using the reference beamforming matrix. The MS estimates an effective channel using the reference beamforming matrix, and calculates the intensity of an interference signal from an interference BS.

Abstract: A method of setting a packet transmission path in a wireless communication network and a network apparatus using the same are provided. A method of setting a packet transmission path includes setting N?1 routing regions including at least one node between a source node and a destination node based on a predetermined N number of hops, N denoting an integer greater than or equal to two, and determining a node in each of the routing regions as a relay node based on a channel gain.

Abstract: An apparatus and a method for canceling interference using a space-frequency block coding in a multi-antenna system. The method includes confirming a code for coding to minimize a Pairwise Error Probability (PEP) of a transmit signal of which the PEP is maximized according to a time variation; and coding the transmit signal with the code and transmitting the coded signal via at least two antennas. Accordingly, the interference cancellation can be accomplished while lowering the complexity of the receiver without degrading the spectral efficiency.

Abstract: Provided are a system and a method for transmitting/receiving data in a communication system. The method includes calculating a processing matrix of a transmission unit for transmitting data, a processing matrix of a reception unit for receiving the data, a channel matrix formed by a plurality of transmission antennas and a plurality of reception antennas, and a parameter of the transmission data, when the data to be transmitted to the plurality of reception antennas via the plurality of transmission antennas is generated; determining a minimum value of a Minimum Mean Square Error (MMSE) according to the calculated matrixes and parameter; and transmitting/receiving the data using an MMSE multiplexing scheme based on the determined minimum MMSE value.

Abstract: An apparatus and a method for efficient resource allocation using a cognitive radio communication in Orthogonal Frequency Division Multiple Access (OFDMA)-based moving networks are provided. The method includes determining a minimum transmit power value of the MRS, which enables the internal terminal to have a receive Signal to Interference and Noise Ratio (SINR) greater than a first threshold; determining a transmit power value of the MRS by taking into account the determined minimum transmit power value; determining a transmit power value of the MRS per cellular terminal, which is transmittable at maximum while exerting interference less than a second threshold on a corresponding cellular terminal; searching one or more cellular terminals having the maximum transmittable transmit power value determined per cellular terminal greater than the determined transmit power value; and borrowing and allocating a resource allocated to the searched cellular terminal to the internal terminal.

Abstract: Disclosed is a method for acquiring synchronization in a mobile communication system using an Orthogonal Frequency Division Multiplexing (OFDM) scheme. The method includes modeling a power delay profile in time-varying frequency selective fading channel conditions by a specific function; detecting a log probability distribution function of a timing offset and a frequency offset in consideration of a correlation between a received signal and the received multi-path signal in the time-varying frequency selective fading channel conditions having the power delay profile modeled as the specific function; and estimating a timing offset and a frequency offset which maximize the log probability distribution function of the timing offset and the frequency offset.

Abstract: An apparatus and a method for efficient resource allocation using a cognitive radio communication in Orthogonal Frequency Division Multiple Access (OFDMA)-based moving networks are provided. The method includes determining a minimum transmit power value of the MRS, which enables the internal terminal to have a receive Signal to Interference and Noise Ratio (SINR) greater than a first threshold; determining a transmit power value of the MRS by taking into account the determined minimum transmit power value; determining a transmit power value of the MRS per cellular terminal, which is transmittable at maximum while exerting interference less than a second threshold on a corresponding cellular terminal; searching one or more cellular terminals having the maximum transmittable transmit power value determined per cellular terminal greater than the determined transmit power value; and borrowing and allocating a resource allocated to the searched cellular terminal to the internal terminal.

Abstract: A method of setting a packet transmission path in a wireless communication network and a network apparatus using the same are provided. A method of setting a packet transmission path includes setting N?1 routing regions including at least one node between a source node and a destination node based on a predetermined N number of hops, N denoting an integer greater than or equal to two, and determining a node in each of the routing regions as a relay node based on a channel gain.

Abstract: An apparatus and a method for canceling interference using a space-frequency block coding in a multi-antenna system. The method includes confirming a code for coding to minimize a Pairwise Error Probability (PEP) of a transmit signal of which the PEP is maximized according to a time variation; and coding the transmit signal with the code and transmitting the coded signal via at least two antennas. Accordingly, the interference cancellation can be accomplished while lowering the complexity of the receiver without degrading the spectral efficiency.

Abstract: Provided are a system and a method for transmitting/receiving data in a communication system. The method includes calculating a processing matrix of a transmission unit for transmitting data, a processing matrix of a reception unit for receiving the data, a channel matrix formed by a plurality of transmission antennas and a plurality of reception antennas, and a parameter of the transmission data, when the data to be transmitted to the plurality of reception antennas via the plurality of transmission antennas is generated; determining a minimum value of a Minimum Mean Square Error (MMSE) according to the calculated matrixes and parameter; and transmitting/receiving the data using an MMSE multiplexing scheme based on the determined minimum MMSE value.

Abstract: Disclosed is a method for acquiring synchronization in a mobile communication system using an Orthogonal Frequency Division Multiplexing (OFDM) scheme. The method includes modeling a power delay profile in time-varying frequency selective fading channel conditions by a specific function; detecting a log probability distribution function of a timing offset and a frequency offset in consideration of a correlation between a received signal and the received multi-path signal in the time-varying frequency selective fading channel conditions having the power delay profile modeled as the specific function; and estimating a timing offset and a frequency offset which maximize the log probability distribution function of the timing offset and the frequency offset.

Abstract: Disclosed is a method for estimating a frequency offset in a mobile communication system that divides a predetermined frequency band by a time division scheme to transmit data signals or divides an entire frequency band into a plurality of sub-frequency bands to transmit the data signals. The method includes the steps of modeling a fast fading channel by one of a linear equation and a polynomial equation; and applying the model to a variable for the channel after performing the modeling and estimating the channel and the frequency offset based on a joint maximum likelihood using a training sequence.

Abstract: A method of transmitting a signal by using an Adaptive Modulation and Coding scheme in a Frequency Hopping-Orthogonal Frequency Division Multiplexing Access communication system capable of dividing total frequency bands into a plurality of sub-carrier bands and including a plurality of sub-channels, which are sets of predetermined sub-carrier bands, and a plurality of cells. The method includes the steps of allocating a predetermined number of sub-channels as AMC sub-channels per each cell matching with predetermined conditions in order to apply the AMC scheme to the AMC sub-channels, and allocating remaining sub-channels except for the AMC sub-channels as FH-OFDMA sub-channels in order to apply an FH-OFDMA scheme to the FH-OFDMA sub-channels.

Abstract: A handoff method in a mobile communication system using frequency hopping-orthogonal frequency division multiplexing (FH-OFDM). A mobile host predicts a handoff according to strength of transmission power of a currently serving base station, reserves a physical channel required for the handoff associated with at least one candidate base station, selects a handoff target base station from the at least one candidate base station, releases a channel with the serving base station, and performs data communication with the target base station through the reserved physical channel.