• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.385-388
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• 1999

A new frequency-variant equivalent circuit model of power/ground plane is presented. The equivalent circuit is modeled with grid cells. The circuit parameters of each cell were extracted by using Fasthenry. To verify the developed circuit model, its s-parameters are compared with the measured s-parameters 〔2〕 and the full-wave simulation-based s-parameters. Consequently, it is shown that our frequency-variant equivalent circuit model can accurately predict imperfect ground effects under the high frequency operation of electronic package.

• 한국데이터정보과학회:학술대회논문집
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• 2002.06a
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• pp.17-22
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• 2002

Availability is an important characteristic of a repairable component. Iyer(1992) obtained the 'limiting efficiency'(not the `steady state availability') of the age-dependent minimal repair model which was first considered by Block et al.(1985). However the existence of the steady state availability of the model has not been reported. In this note, the existence of the steady state availability of the model is shown and a brief remark on the importance of the property is given.

• Journal of the Korean Home Economics Association
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• v.31 no.2
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• pp.15-25
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• 1993

This article studied on price dispersion of food market in Kwangju. Both item and market basket price dispersion were surveyed, and this price dispersion was compared with the perceptive price dispersion. This survey was conducted from April. 8.1992 to 22. On findings, price dispersion is very big in item and market basket. Most Consumers' perception was inaccurate and typically underestimated. This findings suggest that consumers are victims of contributors to informally imperfect markets.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.517-522
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• 2000

When a real robot manipulator is mathematically modeled. uncertainties are not avoidable. The uncertainties are often nonlinear and time-varying. The uncertain factors collie from imperfect knowledge ok system parameters. payload change. friction. external disturbance. and etc. In this paper. we propose a class of robust hybrid controls of manipulators without knowing the exact stiffness and provide the stability analysis. Simulation results are provided to show the effectiveness of the algorithms.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.545-547
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• 1998

Scab disease of Aralia elata (Miq.) Seemann occurred severely in Kangwon province, Korea. First, brown spots were formed on leaves and enlarged along vein. The infected leaves including petiole and midrib were twisted forming scab and died eventually. Also the disease infected twigs and trunks of the tree forming scab. Conidia, ascospores and asci developed in locule were observed in the infected tissue. The causal organism of the scab disease of Araliae elata was isolated and identified as Elsinoe araliae Yamamoto (imperfect stage: Sphaceloma araliae Jenkins) based on the morphological and cultural characteristics, and pathogenic test.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.283-284
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• 2007

In this paper we introduce a compensation of nonlinearity Heterodyne laser interferometer. The Laser Interferometer is used for length measurement in various industries. However, it has nonlinearity error caused by the imperfect optical equipment. This acts as an obstacle in the measurement improvement. We propose an adaptive error compensation using least mean square(LMS) to improve precision.

• Journal of Korean Institute of Industrial Engineers
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• v.22 no.3
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• pp.473-483
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• 1996

For situations where there are several markets with different price/cost structures, economic complete inspection plans are developed for determining the market to ship the product to. Two complete inspection plans are considered; the plan based on the performance variable of interest, and the plan based on a variable which is correlated with the performance variable. Profit models are constructed which involve selling price, cost incurred by imperfect quality, and quality inspection cost. Methods of finding the optimal complete inspection plans are presented and a numerical example is given.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.119-126
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• 1997

본 논문에서는 제품을 생산하는 도중에 생산체계의 상태가 관리상태에서 이상상태로 전이될 수 있는 불완전한 생산체계에 있어서의 경제적 생산주기 결정모형을 다룬다. 생산체계가 관리 상태에 머무는 생산시간이 지수분포를 따른다는 가정하에서 전체 현금흐름의 현재가치를 생산 주기의 함수로 유도하고, 이 함수를 최대화하는 경제적 생산주기의 근사해를 구한다. 근사해에서 출발하여 최적해를 찾아 내는 간단한 알고리즘을 개발하고, 이를 적용한 수치예를 보인다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.375-375
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• 2004

• Journal of the Korean Data and Information Science Society
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• v.9 no.1
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• pp.89-94
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• 1998

We shall propose several Bayes estimators for reliability of a two-unit hot standby system with the imperfect switch based upon a complete sample of failure times observed from an exponential distribution, and the proposed reliability Bayesian estimators are compared numerically each other in sense of mean squared error.