http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
A New Hybrid Genetic Algorithm for Nonlinear Channel Blind Equalization
Han, Soowhan,Lee, Imgeun,Han, Changwook Korean Institute of Intelligent Systems 2004 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.4 No.3
In this study, a hybrid genetic algorithm merged with simulated annealing is presented to solve nonlinear channel blind equalization problems. The equalization of nonlinear channels is more complicated one, but it is of more practical use in real world environments. The proposed hybrid genetic algorithm with simulated annealing is used to estimate the output states of nonlinear channel, based on the Bayesian likelihood fitness function, instead of the channel parameters. By using the desired channel states derived from these estimated output states of the nonlinear channel, the Bayesian equalizer is implemented to reconstruct transmitted symbols. In the simulations, binary signals are generated at random with Gaussian noise. The performance of the proposed method is compared with those of a conventional genetic algorithm(GA) and a simplex GA. In particular, we observe a relatively high accuracy and fast convergence of the method.
A New Hybrid Genetic Algorithm for Nonlinear Channel Blind Equalization
Soowhan Han,Imgeun Lee,Changwook Han 한국지능시스템학회 2004 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.4 No.3
In this study, a hybrid genetic algorithm merged with simulated annealing is presented to solve nonlinear channel blind equalization problems. The equalization of nonlinear channels is more complicated one, but it is of more practical use in real world environments. The proposed hybrid genetic algorithm with simulated annealing is used to estimate the output states of nonlinear channel, based on the Bayesian likelihood fitness function, instead of the channel parameters. By using the desired channel states derived from these estimated output states of the nonlinear channel, the Bayesian equalizer is implemented to reconstruct transmitted symbols. In the simulations, binary signals are generated at random with Gaussian noise. The performance of the proposed method is compared with those of a conventional genetic algorithm(GA) and a simplex GA. In particular, we observe a relatively high accuracy and fast convergence of the method.
김창욱,윤성렬,한승희,나재훈,이창재 광운대학교 신기술연구소 1998 신기술연구소논문집 Vol.27 No.-
합금박막형 자기기록매체의 제작방법은 스퍼터링과 무전해 도금방법이 주로 이용되고 있으며, 미국이나 일본등에서는 스퍼터링 방법에 비하여 대량생산이 용이하고. 도금조건에 따라 다양한 특성의 합금박막을 제조할 수있는 무전해 도금방법을 이용한 합금자성박막에 대하여 많은 연구를 하고 있지만 국내에서는 이에 관한 연구가매우 미약한 실정이다. 따라서 이 연구에서는 차아인산이수소나트륨을 환원제로 사용한 무전해 도금법을 이용하여 corning glass 2948 유리기판 위에 Co-W-P 도금충을 제조할 때, pH 및 온도에 따른 석출속도, 합금조성 및 미세구조와 자기적 특성을 고찰하였다 무전해 Co-W-P 도금충의 경우는 자기적 특성에서 보자력은 5000e, 각형비는 0.6 정도의 경향을 보였지만, 결정배향에 있어서는 α-Co (0002) 방향으로 우선 배향하여 수직자화벡터를 형성함을 확인할 수 있었으며, 합금조성에 있어 인(P)의 함량은 0.8±0.2%로 일정하였고, W의 석출량은 Na_2W0_4의 농도가 증가할수록 증가하여 0.1mol/L일 때 20%이였다 수소가스를 이용한 환원분위기에서100℃간격으로 1시간씩 400℃까지 열처리에 따른 자기적 특성과 미세구조의 변화를 확인하여 본 결과Co-W-P 는 열처리에 따라 표면의 평활도는 향상되었지만, 자기적 특성과 미세구조에는 아무런 변화가 없었다. Usually sputtering and electroless plating methods were used for manufacturing metal-alloy thin film magnetic memory devices. Since electroless plating method has many merits in mass production and product variety compared to sputtering method, many researches about electroless plating have been Performed in the United State of America and Japan. However, electroless plating method has not much been studied in Korea. In these respects the purpose of this research is manufacturing Co-W-P alloy thin film on the corning glass 2948 by electroless plating method using sodium hypophosphite as a reductant, and analyzing deposition rate. alloy composition. microstructure, and magnetic characteristics at various pH's and temperatures. For Co-W-P alloy thin film. coercive force was 5000e and squareness was 0.6. For crystal orientation, (0002) orientation of α-Co was dominatly found. Then we could confirm the formation of perpendicular magnetization. The content of P was constant at 0.8±0.2% and the content of W increased as the concentration of Na_2W0_4 increased. When the concentration ofNa_2W0_4 was 0.1 mol/L. the composition of W was 20%. We observed the changes of magnetic characteristics and microstructure of thin film depositions of Co-W-P by the heat treatment. For heat treatment, the temperature was increased step by step to l00℃, 200℃. 300℃, and 400℃.and it took 1 hour at each step in the reductive condition of hydrogen gas. By the heat treatment. flatness of surface was improved, but there were no changes on the magnetic characteristics and the microstructures.
Ab initio study on the carbon nanotube with various degrees of functionalization
Cho, Eunae,Kim, Hanchul,Kim, Changwook,Han, Seungwu Elsevier 2006 Chemical physics letters Vol.419 No.1
<P><B>Abstract</B></P><P>We present our ab initio results on carbon nanotubes functionalized with dichlorocarbene (CCl<SUB>2</SUB>). We find that the electronic properties of carbon nanotubes are significantly modified depending on the site of [2+1] cycloaddition. The random addition of dichlorocarbene is found to reduce the band gap of semiconducting nanotubes while those of metallic nanotubes are increased. This is related to the quasi-bound states within the energy gap originated from dichlorocarbene, which are revealed at the large supercell calculation.</P>