Abstract: The present invention provides an electroluminescent compound of one of following formulas Formula 1 and Formula 2. Another aspect of the invention is an electroluminescent device including a first electrode; a second electrode facing the first electrode; and at least one organic material layer between the first and second electrodes, wherein one or more of the at least one organic material layer includes the electroluminescent compound.

Abstract: The present invention provides an electroluminescent compound of one of following formulas Formula 1 and Formula 2. Another aspect of the invention is an electroluminescent device including a first electrode; a second electrode facing the first electrode; and at least one organic material layer between the first and second electrodes, wherein one or more of the at least one organic material layer includes the electroluminescent compound.

Abstract: The present invention provides a novel azo compound having a quenching ability for the material that exhibits a luminescent phenomenon at an excited energy level, a quencher comprising the novel azo compound, a use of the quencher and a method for preparing the azo compound. The quencher according to the present invention may exhibit excellent characteristics in a wavelength absorption region.

Abstract: The present invention relates to an oligonucleotide structure and a method for preparing the same and, more particularly, to an oligonucleotide structure in which a polymer compound is linked to an oligonucleotide via a covalent bond to improve in vivo stability of the oligonucleotide and cellular delivery efficiency of the oligonucleotide; and to a method for preparing the same.

Abstract: The present invention relates to an oligonucleotide structure and a method for preparing the same and, more particularly, to an oligonucleotide structure in which a polymer compound is linked to an oligonucleotide via a covalent bond to improve in vivo stability of the oligonucleotide and cellular delivery efficiency of the oligonucleotide; and to a method for preparing the same.

Abstract: The present invention provides a novel azo compound having a quenching ability for the material that exhibits a luminescent phenomenon at an excited energy level, a quencher comprising the novel azo compound, a use of the quencher and a method for preparing the azo compound. The quencher according to the present invention may exhibit excellent characteristics in a wavelength absorption region.

Abstract: The present invention provides a double-stranded RNA structure, which comprises a polymer compound covalently bonded to a double-helix oligo RNA useful for the treatment of diseases, particularly cancer, in order to enhance the delivery of the double-helix oligo RNA, and further comprises a target-specific ligand bonded thereto, a preparation method thereof, and a technique of delivering the double-helix oligo RNA in a target-specific manner using the RNA structure. A nanoparticle composed of the ligand-bonded double-helix oligo RNA structures can efficiently deliver the double-helix oligo RNA to a target, and thus can exhibit the activity of the double-helix oligo RNA even when the double-helix oligo RNA is administered at a relatively low concentration. Also, it can prevent the non-specific delivery of the double-helix oligo RNA into other organs and cells.

Abstract: A communication method and apparatus using a virtual sink node in a wireless sensor network, in which location information about a destination node is acquired by a source node. If the location of the destination node is out of a transmission range of the source node, data including the location information about the destination node are transmitted from the source node to one of nodes adjacent to the source node, where the one node is typically closest to the destination node. The data are transmitted from the one node to another one of nodes adjacent to the one node, where another node is closest to the destination node, until the destination node is located within a transmission range of the one node. If the destination node is located within the transmission range of the one node, the data are transmitted from the one node to the destination node.

Abstract: A mobility management system and method is provided for efficiently support mobility to an IPv6 based LoWpan. The mobility management method for Internet Protocol version 6 (IPv6) based personal area network (PAN) moving with a mobile router according to the present invention includes detecting, at a mobile terminal, movement of the mobile router; determining whether the movement is an intra-network movement or an inter-network movement, transmitting, when the movement is an intra-network movement, a neighbor discovery request message to a gateway of a currently attached network and receiving a neighbor discovery response message containing a temporary address transmitted by the gateway in response to the neighbor discovery request message. When the movement is an inter-network movement, the gateway receives the binding acknowledgement message from a home agent and establishes a bidirectional tunnel with the home agent.

Abstract: A method and apparatus for a sensor network having a plurality of reference nodes and a sensor node that enables the sensor node to compute a relative position through transmission range control and position mapping. In transmission range control, each reference node sends location information signals to the sensor node while varying transmission power. In position mapping, the sensor node forms a grid of vertical and horizontal lines corresponding to a square area defined by the neighboring reference nodes, extracts coordinates of intersections in the grid belonging to a shared region between areas covered by location information signals of various transmit power levels from the neighboring reference nodes, and sets the position of the sensor node to the middle points of the extracted coordinates. Each reference node sends a location information signal when a random backoff time expires after reception of a location information request signal.

Abstract: A method and system for transmitting data from a base station to a mobile station in a wireless communication system using a multiple hop relay scheme is In a multi-hop system having a plurality of nodes, performing bidirectional data transmission between the nodes comprises: grouping the plurality of nodes into a first node group to a fourth node group, and assigning data transmission intervals to the grouped node groups at each frame, the data transmission intervals dividing each frame in time; receiving, by a second group node, data from an upper group node at a first frame and, at the same time, receiving, by a third group node, data from a lower group node; and transmitting by the second group node data to the upper group node at a second frame and, at the same time, transmitting by the third group node data to the lower group node.

Abstract: A method for performing communication in the wireless sensor network is disclosed. The upper node transmits a beacon message to the lower nodes, wherein the beacon message distinguishes an indirect transmission interval, in which the upper node transmits downlink data to the plurality of lower nodes, from a direct transmission interval adjacent to the indirect transmission interval, in which the upper node receives uplink data from the plurality of lower nodes. The lower nodes determine the indirect transmission interval and the direct transmission interval from the received beacon message. The downlink data is transmitted from the upper node to the lower nodes in the indirect transmission interval. The uplink data is transmitted from the lower nodes to the upper node in the direct transmission interval. When communication is performed between the upper node and the lower nodes, the data can be efficiently transmitted from the upper node to the lower nodes.

Abstract: A packet transmission method for a WPAN that for alleviating traffic concentration in an active period and improving network throughput by controlling packet transmission timing in the active period. A packet transmission method for a wireless personal area network including a coordinator operating with a specific duty cycle and a plurality of devices includes determining, when a packet is generated, whether there is another packet waiting to be sent; determining, if there is no other packet waiting to be sent, whether the network is in an inactive period; setting, when network is in an inactive period, a backoff time; and sending the packet when the backoff time has expired. The packet transmission method controls an initial backoff value adaptively to a duty cycle of the network.

Abstract: A medium access control (MAC) frame provision method establishes security in an IEEE 802.15.4 network. A MAC frame is generated, which includes a MAC header, a payload field, and a frame check sequence (FCS) field, the payload field including relevant main data according to a frame type defined in the MAC header. A disguised decoy data sequence number (DSN) is generated and inserted into the MAC header. A real DSN, which is a corresponding transmission sequence number of the MAC frame, is generated and inserted into the payload field. The MAC frame is transmitted, including the encrypted payload field, to a counterpart node. A MAC ACK frame acknowledges reception of the transmitted MAC frame; and a DSN is compared in the received MAC ACK frame with the real DSN. An authentication of the counterpart node is performed when the received MAC ACK frame is equal to the real DSN.

Abstract: A method is provided for registering a mobile router in an Internet Protocol version 6 over Low power Wireless Personal Area Network (6LoWPAN) network. The mobile router detects movement into a wireless network through the reception of a beacon message, and sends a Router Solicitation (RS) message requesting registration in the wireless network to a gateway. The gateway acquires an address of the mobile router from the RS message, stores the acquired address, assigns a new address to be used in the wireless network to the mobile router, and sends a Router Advertisement (RA) message with assigned address information and gateway address information, to the mobile router. The mobile router acquires the assigned address information and the gateway address information from the RA message.

Abstract: A method is provided for supporting mobility of a Mobile Node (MN) in a multi-hop Internet Protocol (IP) network, in which an MN that has moved from a source Personal Area Network (PAN) to a target PAN, sends a Router Solicitation (RS) message with an option for requesting its profile to a gateway of the target PAN, and receives a Router Advertisement (RA) message from the gateway in response to the RS message. The RA message includes a home prefix of the MN as the requested profile. The method supports mobility of MNs, enables unicast communication, and facilitates efficient use of the network.

Abstract: A system and method for exactly estimating a volume of traffic is provided when packets are transferred within the network. The system and method receive data packets from clients through a plurality of router-for-clients, and creating a flow information packet for estimating information about a flow, transfer the data packets and the created flow information packet to the destination router-for-client via a router-for-relay, calculate information about the traffic of a flow at the destination router-for-client through the flow information packets transferred from the router-for-clients, and estimate a volume of the traffic. Thus, the system and method can estimate the volume of the traffic on the network with respect to the aggregated flow defined by the router pair connected to the terminal or the external network when the traffic is actually introduced into the network, instead of the flows of each terminal and each destination.

Abstract: A hybrid channel assignment method comprising the steps of negotiating among routers to select one router to act as a central server; collecting, at the selected router, information on an entire network transmitted from the other routers, and assigning channels based upon the information on the entire network; and reassigning channels of respective routers based upon dynamically-changing traffic characteristics. The hybrid channel assignment method can assign channels using both centralized processing and distributed processing in order to ensure optimally correct channel assignment consistent with present traffic characteristics. This as a result can prevent network resources from being wasted and also increase network capacity, thereby optimizing effective use of the network resources.

Abstract: A mobility header compression method and system for an IPv6-based LoWPAN is provided for supporting IPv6 mobility to the IPv6-based LoWPAN checks a packet carrying data and a first and a second headers containing transmission information about the data to determine whether the second header contains a compressed Internet Protocol version 6 (IPv6) information. When the second header contains a compressed IPv6 information, ands followed by a mobility header, a mobility support-indicative field of the first header is set to indicate that the second header is followed by the mobility header and the rest of the fields of the second header are compressed except for the mobility header-indicative field. A mobility information-indicative field of the mobility header is set to indicate inclusion of mobility information; and the rest of the fields of the mobility header are compressed except for the mobility information-indicative field.

Abstract: A communication terminal and method is provided for improving channel utilization efficiency in a wireless sensor network using contention-based channel access mechanism is disclosed. The communication method according to the present invention comprises initializing, when a packet transmission is required, a contention window to a size; resetting, when a channel is assessed to be busy, the size of the contention window in a hybrid expansion mode; and attempting, when the channel is assessed to be idle, the packet transmission through the channel.