• 제목/요약/키워드: cost Index

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수요예측에 오차를 고려한 신뢰도 지수 산정에 관한 연구 (A STUDY ON THE GENERATING SYSTEM RELIABILITY INDEX EVALUATION WITH CONSIDERING THE LOAD FORECASTING UNCERTAINTY)

  • 송길영;김용하;차준;오광해
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 하계학술대회 논문집
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    • pp.402-405
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    • 1991
  • This paper represents a new method for computing reliability indices by using Large Deviation method which is one of the probabilistic production cost simulations. The reliability measures are based on the models used for the loads and for the generating unit failure states. In computing these measures it has been tacitly assumed that the values of all parameters in the models are precisely known. In fact, however, some of these values must often be chosen with a considerable degree of uncertainty involved. This is particularly true for the forecast peak loads in the load model, where there is an inherent uncertainty in the method of forecasting, which are frequently based on insufficient statistics. In this paper, the effect of load forecasting uncertainty on the LOLP(Loss of Load Probability), is investigated. By applying the Large Deviation method to the IEEE Rilability Test System, it is verified that the proposed method is generally very accurate and very fast for computing system reliability indices.

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TACT 공정관리 시스템 개발 및 적용 사례 (Development and Application of TACT Management System)

  • 김재호;서상욱;김선국;김창덕;이현수
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2003년도 학술대회지
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    • pp.126-134
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    • 2003
  • 건설산업의 환경변화와 정보기술의 발달에 따라 건설사업 효율성 향상의 필요성이 커지고 있다. 그러나 건설사업의 효율성 제고를 위한 관리시스템의 필수요건이 되는 성과측정 도구는 여전히 부족한 실정이다. 한편, 공정관리의 경우, 공사수행 결과로 나타나는 시간, 비용, 진도율 등의 실적위주로 관리되고 있으며, 진행단계에서의 전체 작업간의 연속적 흐름에 대한 관리는 제대로 이루어지지 못하고 있다. 따라서 본 연구에서는 건축공사의 계획단계에서부터 진행단계, 최종 평가에 이르는 프로세스의 시스템화를 시도하였고, 특히 택트 공정관리의 시스템화를 통하여 공사수행 과정 중의 마감공사 수행 정도를 측정할 수 있는 지표를 개발하고 이를 활용하는 방안을 제시하였다.

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양면 지문 입력 방법 (A Double-Sided Fingerprint Sensing Method)

  • 심재창;김세영;최미순;김익동
    • 한국멀티미디어학회논문지
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    • 제11권3호
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    • pp.323-330
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    • 2008
  • 본 논문에서는 지문입력에서 회전에 의한 오차를 줄이는 방법으로 기존의 지문 입력기를 개선한 새로운 지문 입력 방법을 제안한다. 일반적인 지문 센서는 센서 위에 손가락을 올려서 지문 영상을 획득하는데 주의를 해도 회전이 발생하여 인식률에 영향을 미친다. 개선된 입력 방법은 엄지와 검지의 사이에 지문입력기를 두어 회전을 최소화하는 방법이다. 반도체 지문 입력기를 양쪽으로 부착하여 엄지와 검지를 동시에 집게 형태로 쥐어서 지문을 입력하는 방법이다. 이 방법은 지문을 획득할 때 마다 거의 같은 각도를 유지한다. 실험결과 제안된 방법이 인식률이 향상되었다. 단점으로는 하드웨어 비용이 더 추가 된다.

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초등학생의 올바른 식습관 형성을 위한 영양교육 사이트 개발 (Development of Computer-Aided Nutritional Education Program for the School Children)

  • 허은실;이경혜
    • Journal of Nutrition and Health
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    • 제35권7호
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    • pp.791-799
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    • 2002
  • The performance of educational program for preventive nutrition is more beneficial for children than for the adults based on the cost reduction and the effect of this education. Also children's education helps them to grow and to live as a healthy adult. The purpose of this study is to solve the nutritional problem in children by developing nutrition education program for children and correct their nutritional problems. The characteristics of this program (www.food79.net) are the customized program for grade level based on the level of learning ability, the various education method such as game, cooking practice, and quiz, animation, and the self educated method by managing children's meal management as the result. The contents of this site are constructed not only for children but also for parents, the teachers and the school dietitians to increasing educational effect. The children room consists of food tower, nutrition kingdom, calculation of obesity index, food information, nutrient exploration, cooking world, and evaluation of dietary life. In the room for dietitian and teachers include the contents of the easy gymnastics, nutrition counseling methods, the teaching plans for nutrition education, and the information interchange corner. The third room for parents is constructed of nutrition evaluation, food 114, correction of living habits, and free discussion. Through this site, we are expecting to contribute to national health promotion by correcting the food habits of children.

배전지능화 시스템을 위한 배전계통 구분개폐기 교체 우선순위 결정에 관한 연구 (A Study on the Prioritization of Sectional Switchgear Replacement for Intelligent Distribution Automation in Distribution System)

  • 성인제;채희석;문종필;서인용;김재철
    • 조명전기설비학회논문지
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    • 제29권9호
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    • pp.51-58
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    • 2015
  • Intelligent distribution automation system includes operating a switchgear of distribution system remotely when switchgear are not available to operate quickly. This system makes it possible to reduce the interrupt time. It also aims to improve the reliability of customers. Currently, Intelligent distribution automation improves the reliability by replacing manual switchgear, which is installed as sectional switchgear. However the prioritization of the replacement for the switchgear is required for its intellectualization. Many studies have been conducted related with prioritization of switchgear replacement. But it is difficult to interpret and apply to the power distribution system. That is because most of the studies just considers customer numbers for prioritizing the replacement. In this paper presents an algorithm to determine the intelligent swichgear replacement priority considering customer number, load quantity and interruption cost. Further, this algorithm is verified by using system reliability index.

농촌 고령자 공동시설지원 시범사업 주민만족도 조사 연구 (A Study on the Inhabitant's Satisfaction of Community Facilities Demonstration Project for Rural Elderly)

  • 김진환;박중신;송서호
    • 한국농촌건축학회논문집
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    • 제17권4호
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    • pp.9-16
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    • 2015
  • This study examined the current conditions of the community facilities constructed by demonstration project for rural elderly that were promoted for the last two years by the ministry of agriculture, food and rural affairs. The type of community facilities are community living home, community food service facility and small bath house. And it was accomplished satisfaction survey for analyzing the effects of demonstration project focused on inhabitants and users of community facilities constructed by demonstration project. The results are as follows. First, The satisfaction index of community facilities was evaluated high level in generally. Second, Inhabitants and users of facilities were presented high level satisfaction in humanity sector, especially. Third, It should be to establish maintenance and management plan such as supporting of linkage program and operation cost for secure the sustainability. Consequently, the implementation of community facilities demonstration project to improve the living conditions of rural elderly is entirely appropriate. The results of this study were considered to promoting demonstration project for improving quality of the facilities and securing effectiveness of the project.

Sparse Signal Recovery via Tree Search Matching Pursuit

  • Lee, Jaeseok;Choi, Jun Won;Shim, Byonghyo
    • Journal of Communications and Networks
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    • 제18권5호
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    • pp.699-712
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    • 2016
  • Recently, greedy algorithm has received much attention as a cost-effective means to reconstruct the sparse signals from compressed measurements. Much of previous work has focused on the investigation of a single candidate to identify the support (index set of nonzero elements) of the sparse signals. Well-known drawback of the greedy approach is that the chosen candidate is often not the optimal solution due to the myopic decision in each iteration. In this paper, we propose a tree search based sparse signal recovery algorithm referred to as the tree search matching pursuit (TSMP). Two key ingredients of the proposed TSMP algorithm to control the computational complexity are the pre-selection to put a restriction on columns of the sensing matrix to be investigated and the tree pruning to eliminate unpromising paths from the search tree. In numerical simulations of Internet of Things (IoT) environments, it is shown that TSMP outperforms conventional schemes by a large margin.

CO2 배출량을 고려한 가용송전용량 계산에 관한 연구 (Available Transfer Capability Evaluation Considering CO2 Emissions Using Multi-Objective Particle Swarm Optimization)

  • 천이경;김문겸;류재근;박종근
    • 전기학회논문지
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    • 제59권6호
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    • pp.1017-1024
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    • 2010
  • Under the Kyoto Protocol many countries have been requested to participate in emissions trading with the assigned $CO_2$ emissions. In this environment, it is inevitable to change the system and market operation in deregulated power systems, and then ensuring safety margin is becoming more important for balancing system security, economy and $CO_2$ emissions. Nowadays, available transfer capability (ATC) is a key index of the remaining capability of a transmission system for future transactions. This paper presents a novel approach to the ATC evaluation with $CO_2$ emissions using multi-objective particle swarm optimization (MOPSO) technique. This technique evolves a multi-objective version of PSO by proposing redefinition of global best and local best individuals in multi-objective optimization domain. The optimal power flow (OPF) method using MOPSO is suggested to solve multi-objective functions including fuel cost and $CO_2$ emissions simultaneously. To show its efficiency and effectiveness, the results of the proposed method is comprehensively realized by a comparison with the ATC which is not including $CO_2$ emissions for the IEEE 30-bus system, and is found to be quite promising.

Coordinated Voltage and Reactive Power Control Strategy with Distributed Generator for Improving the Operational Efficiency

  • Jeong, Ki-Seok;Lee, Hyun-Chul;Baek, Young-Sik;Park, Ji-Ho
    • Journal of Electrical Engineering and Technology
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    • 제8권6호
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    • pp.1261-1268
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    • 2013
  • This study proposes a voltage and reactive coordinative control strategy with distributed generator (DG) in a distribution power system. The aim is to determine the optimum dispatch schedules for an on-load tap changer (OLTC), distributed generator settings and all shunt capacitor switching on the load and DG generation profile in a day. The proposed method minimizes the real power losses and improves the voltage profile using squared deviations of bus voltages. The results indicate that the proposed method reduces the real losses and voltage fluctuations and improve receiving power factor. This paper proposes coordinated voltage and reactive power control methods that adjust optimal control values of capacitor banks, OLTC, and the AVR of DGs by using a voltage sensitivity factor (VSF) and dynamic programming (DP) with branch-and-bound (B&B) method. To avoid the computational burden, we try to limit the possible states to 24 stages by using a flexible searching space at each stage. Finally, we will show the effectiveness of the proposed method by using operational cost of real power losses and voltage deviation factor as evaluation index for a whole day in a power system with distributed generators.

최적화 기법을 이용한 점탄성물질의 분수차 미분모델 물성계수 추정 (Identification of Fractional-derivative-model Parameters of Viscoelastic Materials Using an Optimization Technique)

  • 김선용;이두호
    • 한국소음진동공학회논문집
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    • 제16권12호
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    • pp.1192-1200
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    • 2006
  • Viscoelastic damping materials are widely used to reduce noise and vibration because of its low cost and easy implementation, for examples, on the body structure of passenger cars, air planes, electric appliances and ships. To design the damped structures, the material property such as elastic modulus and loss factor is essential information. The four-parameter fractional derivative model well describes the dynamic characteristics of the viscoelastic damping materials with respect to both frequency and temperature. However, the identification procedure of the four-parameter is very time-consuming one. In this study a new identification procedure of the four-parameters is proposed by using an FE model and a gradient-based numerical search algorithm. The identification procedure goes two sequential steps to make measured frequency response functions(FRF) coincident with simulated FRFs: the first one is a peak alignment step and the second one is an amplitude adjustment step. A numerical example shows that the proposed method is useful in identifying the viscoelastic material parameters of fractional derivative model.