• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.307-310
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• 2005

우리는 레일리 페이딩 채널에서 다중 전송 안테나를 사용한 전송 방식을 택한 Alamouti 방식의 전송쌍 에러 확률(Pairwise error probability)을 사용해서 시스템의 성능을 분석해 보았다. 데이터는 시공간 블록 코딩을 사용해서 전송 안테나에 n 개의 배열로 전송되어졌다. 각각의 수신안테나의 수신 신호는 채널의 상태에 따라 변형된 n개의 송신 신호들의 선형결합으로 수신된다. 최대 가능도 복호 알고리즘(Maximum likelihood decoding algorithm)은 신호를 다시 재결합하는 간단한 방법을 사용하였다. 이러한 방식은 시공간 블록코드의 직교적인 성질을 이용한 것이고, 수신기에서의 수신신호가 선형결합이라는 것을 바탕으로 한 것이다. 모의실험을 통해서 시공간 블록 코딩을 사용하고, 다중 안테나를 사용한 시스템에서 우리가 분석한 결과를 확인했다.

• Applied Chemistry for Engineering
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• v.2 no.3
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• pp.222-228
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• 1991

The cmc values of the arbitrary surfactants were estimated by the method of the multivarial explanation by the computer that put in the suitable score of the various kinds of the structural unit. The 1.00 in the total. We can obtain reasonably accurate cmc values for the surfactant with the simple molecular structure.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2017.06a
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• pp.59-62
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• 2017

본 논문에서는 평균 밝기 부분에 가중치 맵으로써 감마 변환에 기반한 선형 결합을 제안하고자 한다. 기존의 패치를 기반으로 한 가중치 맵은 평균 밝기 부분에서 영상 내 밝기 값이 한쪽으로 치우쳐 영상의 밝은 부분이 과포화 상태가 되어 세부 정보가 손실되는 단점이 있다. 이에 본 논문에서는 전역적 및 지역적 영상의 평균 밝기 값을 이용하여 감마 변환된 값을 선형 결합 시켜줌으로써 영역 내 세부 정보를 보존시키고 주관적 화질을 향상시켰다. 실험을 통해 결과를 분석하고 성능을 비교하여 기존 알고리듬에 비해 제안한 알고리듬이 우수함을 증명하였다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.2
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• pp.324-330
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• 1990

In this study, in order to perform dynamic design of machine tools reasonably and effectively, a method was formulated to be applicable to the damped structures connected by joints having elasticity and damping by using substructure synthesis method. And a nonlinear solution method was proposed and it formulates the nonlinear parts by describing functions and uses the reducing transformation matrix by the substructure synthesis method. The results of frequency response analysis of a machine tool, where an NC lathe was partitioned by three parts of spindle, housing and bed-base part and the nonlinearity of bearing parts between spindle and housing was modelled, showed force dependency of the response.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.12
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• pp.2240-2246
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• 2007

Optically coupled linear isolation amplifier requires special care to avoid oscillation in actual applications. In this paper methods to analyze the frequency characteristics of the amplifier are proposed to reveal the cause of oscillation and to provide design guidelines. The loop gain of the amplifier obtained through the equivalent circuit model shows that the phase margin is too small to ensure stable operations. Methods to get non-oscillatory response are proposed and the resulting frequency responses are analyzed. The common method adding a small capacitor to the amplifier is shown to degrade the frequency bandwidth. The frequency response of output voltage explains the need of filter capacitor in output stage. The usefulness of the method is verified through experiments.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10a
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• pp.397-400
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• 2001

본 논문에서는 운전 단계중의 상용소프트웨어 성장활용을 설명한 수 있고 또 현장 고장 데이타로부터 활용성장을 예측하는데 관계되는 인자를 결합할 수 있는 새로운 모델을 개발한다. 이 모델은 상용 소프트웨어의 실제 황용이 시간의 멱수 함수로 나타난다는 가정으로부터 생기는 웨이블 분포에 근거한다. 선형신뢰도모델은 잔여결함의 평균크기와 작업량이 일정하고 겉보기 결함밀도가 실제 결함밀도와 동일하다는 가정 하에 유도된다. 기하학적모델은 결함을 수정함에 따라 평균결합크기가 기하학적으로 감소한다는 가정에 있어서 파이가 있다. 한편, Rayleigh모델은 잔여 결함의 평균크기가 시간에 따라 선형적으로 감소한다는 가정에 있어서 차이가 있다. 본 논문에서는 소프트웨어의 신뢰도 요인의 거동을 가정하여 이러한 다양성을 수용하기 위한 모델링을 하였다.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.6
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• pp.781-786
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• 2008

In this paper, we propose a novel approach predicting the fluctuation of stock index by finding a relation in various stock indexes that are represented by linear combinations. The important points are to select stock indexes related to predicting indexes and to find the proper relations in them. Since it is unattainable to use entire stock indexes relation, we used only data that are closely associated with each other. We used Genetic Algorithm(GA) to find the most suitable stock-index relation. We simulated the investment in years from 2005 to 2007 with each real index. Finally we verified that the investment money increased 230 percents by the proposed method.

• The Korean Journal of Applied Statistics
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• v.19 no.3
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• pp.535-544
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• 2006

We consider use of Bootstrap calibration in the problem of setting a confidence interval for a linear combination of variance components. Based on the the modified large sample(MLS) method by Graybill and Wang(1980), Bootstrap Calibration is applied to improve the coverage probability of the MLS confidence bound when the experiment is balanced and coefficients of a linear combination are positive. Performance of the proposed confidence bound in small sample is investigated by simulation studies.

• Journal of KIISE:Software and Applications
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• v.30 no.7_8
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• pp.744-751
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• 2003

A hybrid least square Support Vector Machine combined with First Principle(FP) knowledge is proposed. We compare hybrid least square Support Vector Machine(HLS-SVM) with early proposed models such as Hybrid Neural Network(HNN) and HNN with Extended Kalman Filter(HNN-EKF). In the training and validation stage HLS-SVM shows similar performance with HNN-EKF but better than HNN, whereas, in the testing stage, it shows three times better than HNN-EKF, hundred times better than HNN model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.7
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• pp.715-722
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• 2016

In this paper, by applying the linear least squared error algorithm, we derive an estimation technique for three dimensional target location when a number of radars are used in detecting a target. The proposed technique is then enhanced by combining GPS information and by assigning variable weights to information sources. The enhanced performance of proposed techniques is confirmed via simulation. It is also observed from simulation results that the performance is robust to the uncertainty of information.