• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.201-207
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• 2007

At an early design stage of rail track, dynamic analyses using a standard vehicle model of ADAMS/Rail are employed. In the real field, it is very difficult to find an optimal solution on the designing of rail track considering future operating vehicles because the construction of rail track should be done in the advance of vehicle selection and operation. Using a standard vehicle model of ADAMS/Rail, however the better selection among designed rail tracks is possible by comparing the dynamic analysis.

• 한국정보통신학회논문지
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• 제12권6호
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• pp.1128-1133
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• 2008

상황인식(Context-aware)은 인간-컴퓨터 상호작용의 단점을 극복하기 위한 방법으로써 많은 주목을 받고 있다. 본 논문에서는 UoC(Ubiquitous system on Chip)로 구현될 수 있는 상황인식 시스템 구조를 제안한다. 본 논문은 유비쿼터스 컴퓨팅 시스템을 구현하기 위해 CRS(Context Recognition Switch)와 DOS(Dynamic and Optimal Standard)의 개념을 포함한 Pre-processor, HPSP(High Performance Signal Processor), Network Topology Processor의 부분으로 구성된 UoC Architecture를 제안한다. 또한, IEEE 802.15.4 WPAN(Wireless Personal Area Network) Standard에 의해 구현된 UoC를 보여준다. 제안된 상황인식 기반의 UoC Architecture는 주거 환경에서 컨텍스트를 인식하여 사용자를 지원하는 지능형 이동 로봇 등에 적용될 수 있을 것이다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.361-364
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• 2008

최근 언제 어디서나 컴퓨팅이 가능한 Ubiquitous Computing System 을 구현하기 위한 연구가 활발히 진행되고 있다. 또한, 이를 구현하기 위해 사용자의 상황에 따라 최적의 서비스를 제공하기 위한 상황인식 (Context-awareness) 컴퓨팅 기술 또한 많은 연구가 진행되고 있다. 본 논문에서는 Ubiquitous Computing System 을 구현하기 위해 복합 센서로부터 입력되는 다양한 상황 정보에 대해 CRS(Context Recognition Switch) 개념을 포함하여 보다 정확하고 빠르게 사용자의 상황 정보를 추출하게 된다. 또한 제안된 DOS(Dynamic and Optimal Standard) 개념으로부터 노드의 고유 속성을 분석하여 특화된 시스템 서비스가 가능한는 IEEE 802.15.4 WPAN Standard 기반의 UoC(Ubiquitous system on Chip) Architecture 를 제안하였다.

• Communications for Statistical Applications and Methods
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• 제16권4호
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• pp.595-603
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• 2009

통상적으로 표준적인 최적배분은 층별 조사비용을 고려하여 표본을 배분한다. 만일 조사단위당 비용이 서로 다를 경우 보다 현실적인 배분방법을 고려할 필요가 있다. 즉, 개별 조사단위의 특성에 따라 이익비용비를 최대로 하는 단위를 먼저 표본으로 고려하는 동적배분을 고려하였다. 이러한 관점에서 층별 표본수를 배분하고, 배분된 표본규모에 따라 임의로 표본을 선정하는 방식인 표준적인 최적배분과는 차이가 있다. 이 논문은 약물오용, 낙태, 알콜중독 등과 같은 민감한 특성을 조사하는 층화확률화 응답기법에 대해 각 층별로 표본을 배분할 경우 최적 동적배분을 고려하여 보다 현실적인 문제를 해결하고자 하였으며, 수치적 예제를 통해 동적배분 방법의 효과성을 증명하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1281-1284
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• 1997

In this article, the configuration of weight lifer is analyzed using manipulibility polytope. After modeling body as 7-link redundant robot, optimal joint angles during first stage are searched by dynamic programmi technique and compared with standard reference data.

• Journal of Electrical Engineering and Technology
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• 제12권4호
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• pp.1386-1396
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• 2017

In this paper, a new approach is proposed to select the optimal sitting and sizing of distributed solar photovoltaic generation (SPVG) in a radial electrical distribution systems (EDS) considering load/generation uncertainties. Here, distributed generations (DGs) allocation problem is modeled as optimization problem with network loss based objective function under various equality and inequality constrains in an uncertain environment. A boundary power flow is utilized to address the uncertainties in load/generation forecasts. This approach facilitates the consideration of random uncertainties in forecast having no statistical history. Uncertain solar irradiance is modeled by beta distribution function (BDF). The resulted optimization problem is solved by a new Dynamic Harmony Search Algorithm (DHSA). Dynamic band width (DBW) based DHSA is proposed to enhance the search space and dynamically adjust the exploitation near the optimal solution. Proposed approach is demonstrated for two standard IEEE radial distribution systems under different scenarios.

• 한국통신학회논문지
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• 제33권6A호
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• pp.666-675
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• 2008

현재 IEEE 802.22에서는 스펙트럼 사용 효율을 높이고 새로운 무선 통신 서비스 도입을 용이하게 하기 위한 연구가 활발히 진행되고 있다. 또한 TV 대역을 대상으로 주파수를 공유하고자 하는 Cognitive Radio를 적용한 WRAN 시스템에 대한 표준화가 진행되고 있다. 본 논문에서는 WRAN 시스템에서의 주파수 효율과 채널 용량을 극대화하구 인접 셀 간 간섭을 최소화할 수 있도록 하는 효율적인 주파수 할당 기법과 최적 전력 제어 기법인 PCPWF(Partial Constant Power Water Filling)을 제시하였다. 또한 제안된 동적 셀 설계(dynamic cell plan)를 통해 가용할 수 있는 채널을 효율적으로 할당하여 전체 시스템의 데이터 처리율(throughput)과 형평성을 극대화하였으며, 제안된 기법의 효용성을 검증하기 위해서 시뮬레이션 결과도 수록하였다.

• Journal of Electrical Engineering and Technology
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• 제10권1호
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• pp.56-63
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• 2015

The optimization is an important role in wide geographical distribution of electrical power market, finding the optimum solution for the operation and design of power systems has become a necessity with the increasing cost of raw materials, depleting energy resources and the ever growing demand for electrical energy. In this paper, the real coded biogeography based optimization is proposed to minimize the operating cost with optimal setting of equality and inequality constraints of thermal power system. The proposed technique aims to improve the real coded searing ability, unravel the prematurity of solution and enhance the population assortment of the biogeography based optimization algorithm by using adaptive Gaussian mutation. This algorithm is demonstrated on the standard IEEE-30 bus system and the comparative results are made with existing population based methods.

• 한국전문물리치료학회지
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• 제11권1호
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• pp.35-43
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• 2004

There were two purposes of this study. The first was to research the effects of standard and fixed-split keyboards on wrist posture and movements during word processing. The second was to select optimal computer input devices in order to prevent cummulative trauma disorder in the wrist region. The group of subjects consisted of thirteen healthy men and women who all agreed to participate in this study. Kinematic data was measured from both wrist flexion and extension, and wrist radial and ulnar deviation during a 20 minute period of word processing work. The measuring tool was an electrical goniometer, and was produced by Biometrics Cooperation. The results were as follows: 1. The wrist flexion and extension at resting starting position were not significantly different (p>.05), however the angle of radial and ulnar deviation were significantly different in standard and split keyboard use during word processing (p<.05). 2. In the initial 10 minutes, the dynamic angle of wrist flexion and extension were not significantly different (p>.05), however the dynamic angle of radial and ulnar deviation was significantly different in standard and split keyboard use during word processing (p<.05). These results suggest that the split keyboard is more optimal than the standard keyboard, because it prevented excessive ulnar deviation during word processing.

• 한국국방경영분석학회지
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• 제24권2호
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• pp.130-145
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• 1998

This paper is concerned with the optimization of a system reliability. Two kinds of the reliability model for optimal allocation of parallel redundancy are considered. The algorithm for solving the optimal redundancy problem is proposed by the use of dynamic programming(DP) method. The problem is approached with a standard DP formulation and the DP algorithm is applied to the model and then the optimal solution is found by the backtracking method. The method is applicable to the models having no constraints or having a cost constraint subject to a specified minimum requirement of the system reliability. A consequence of this study is that the developed computer program package are implemental for the optimization of the system reliability.