Abstract:
A method of and an authentication server for distributing a key are disclosed. According to an embodiment of the present invention, the method of distributing a key, which is distributed by an authentication server connected with wireless terminals through a communication network, for encrypting and decrypting data in accordance with providing a service can include: obtaining characteristic information by decrypting encrypted characteristic information that has been received from each of n number of wireless terminals; generating a random key; generating a group key used for encrypting and decrypting data in accordance with providing a service; and generating a distribution key by using the random key, the group key and the characteristic information, and transmitting the distribution key to each wireless terminal.
Abstract:
Disclosed is a block copolymer formed by coupling the following components with each other: (a) a copolymer (A) of a polyethylene glycol (PEG) type compound with a biodegradable polymer; and (b) at least one oligomer (B) selected from the group consisting of poly(β-amino ester) and poly(amido amine). A method for preparing the same block copolymer, and a polymeric hydrogel type drug composition comprising the temperature and pH-sensitive block copolymer and a physiologically active substance that can be encapsulated with the block copolymer are also disclosed. The multiblock copolymer is obtained by copolymerization of a pH-sensitive poly(β-amino ester) and/or poly(amido amine) type oligomer, a hydrophilic and temperature-sensitive polyethylene glycol type compound and a hydrophobic and biodegradable polymer. Therefore, the block copolymer can form a polymeric hydrogel structure due to its amphiphilicity resulting from the combination of a hydrophilic group and a hydrophobic group in the copolymer and ionization characteristics depending on pH variations, and thus can be used as a drug carrier for target-directed drug delivery depending on pH variations in the body.
Abstract:
A frequency synchronization apparatus includes: a correlating unit that obtains a first correlation value by correlating a known reference guard interval of an OFDM symbol and a reference copy interval corresponding to the reference guard interval, and obtains a second correlation value by correlating the estimate guard interval and an estimate copy interval corresponding to the estimate guard interval; a determining unit that compares the first and second correlation values to determine a first case where the first correlation value is larger by a pre-set magnification than the second correlation value, a second case where the second correlation value is larger by a pre-set magnification than the first correlation value, and a third case which is not the first case nor the second case; and a frequency offset estimating unit that estimates a frequency offset by using a correlation value corresponding to any one of the first to third.
Abstract:
Disclosed herein is a manufacturing method of metal oxide nanostructure, including the steps of: (S1) supplying a precursor containing a first metal, a precursor containing a second metal and oxygen onto a substrate; (S2) forming an amorphous second metal oxide layer on the substrate; (S3) forming first nuclei containing the first metal as a main component and second nuclei containing the second metal as a main component on the substrate; (S4) converting the first nuclei into single crystalline seed layers spaced apart from each other and converting the second nuclei into amorphous layers surrounding the first nuclei; and (S5) selectively forming rods on the seed layers and then growing the rods.The manufacturing method of metal oxide nanostructure is advantageous in that the area and thickness of an amorphous layer can be controlled by controlling the flow rate of the main component of the amorphous layer and the flow rate of the main component of the single crystalline seed layer, thereby controlling the density and diameter of the seed layer.
Abstract:
The present invention relates to a novel function of Msx1 protein for inhibiting tumor angiogenesis and metastasis by targeting mTOR (mammalian target of rapamycin) signaling pathway, and for treating a cancer in a subject. Particularly, Msx1 suppresses mTOR through a direct interaction with mTOR, resulting in the inhibition of angiogenesis. The Msx1 significantly suppresses tumor angiogenesis that is necessary for the growth, invasion, and metastasis of solid tumors. Ad-Msx1 can be used to effectively inhibit tumor metastasis by suppressing angiogenesis, tumor cell invasion, and migration.
Abstract:
The reclosing control device configured to perform a reclosing control in case of a fault in a transmission line. Further, the reclosing control device includes a voltage detection unit configured to detect a faulted phase voltage waveform and extract a harmonic component contained in the faulted phase voltage waveform; a HR calculating unit configured to calculate ratio values between even harmonics and odd harmonics based on the extracted harmonic component; and a reclosing control unit configured to determine whether or not an arc is finally extinguished based on the calculated ratio value and perform a reclosing control depending on a result of the determination.
Abstract:
Disclosed herein is a user interface apparatus and control method for the control of service robots. The user interface apparatus for the control of service robots includes an interaction server, an index block, and a robot control server. The interaction server receives control commands to control a service robot from a user, analyzes the control commands, and outputs the results of the analysis to the user. The index block determines the degree of difficulty of each of the analyzed control commands. The robot control server determines the operating mode of the service robot depending on the analyzed control command and the degree of difficulty, and controls the service robot in the determined operating mode.
Abstract:
The present invention relates to a block copolymer formed by coupling the following components with each other, as well as a hydrogel composition comprising the block copolymer and a hydrogel formed from the composition: (a) a copolymer of a polyethylene glycol (PEG)-based compound with a biodegradable polymer; and (b) a sulfonamide-based oligomer. The inventive block copolymer shows the sol-gel transition behavior sensitive to changes in not only temperature but also pH. Thus, the inventive block copolymer overcomes the shortcomings of temperature-sensitive copolymers, form a more strong and stable hydrogel, and is stable in vivo. Accordingly, the inventive block copolymer can be used in various applications in the medical and drug delivery fields.
Abstract:
The present invention relates to a novel graphene oxide reducing agent and a method for manufacturing a reduced graphene oxide from graphene oxide using same. More particularly, in the present invention, the reduced graphene oxide is manufactured by reducing a graphene oxide using a reducing agent containing a halogen element, and is applicable as an electric conductor, a semiconductor, and an insulator in various fields.
Abstract:
There is provided an integrated control method for eliminating a low frequency ripple in a power conversion system for a fuel cell, more particularly, a control method of a power conversion system capable of eliminating a low frequency ripple, controlling a DC link voltage, and controlling an output power and a system using the same control method. A power conversion system (PCS) that converts an output of a DC power supply received from an external power supply includes a converter that converts a voltage of the input power supply; an inverter that converts an output voltage of the converter into an AC voltage; and a converter control module that outputs a PWM signal for controlling a switch of the converter, and after receiving a power instruction value, the converter control module generates the PWM signal for controlling the converter based on the power instruction value.