• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.95-97
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• 2007

In this paper, we propose the optimal lag size which is optimize the performance of the fixed-lag minimum variance FIR smoother. Since the performance of estimation is represented with two Riccati equation and the nonlinear equation of lag size, it is difficult to obtain the optimal lag size. Therefore, we consider the optimal lag size for the scalar system and the numerical example is provided to demonstrate the proposed algorithm.

• 응용통계연구
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• 제3권2호
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• pp.55-77
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• 1990

지금까지의 단일 block size를 전제로 한 E-optimal block design들을 다수 block size로 확 장하는 문제를 종합 정리하고(Lee & Jacroux(1987) 참조), 이를 토대로 기존의 단일 block size를 갖는 block design의 table들을 이용하여 여러 block size의 종류들 중에서 우선 실용 도가 가장 높은 경우인 두 가지 상이한 block size를 갖는 새로운 E-optimal block design의 table을 제작하였음.

• 한국정밀공학회지
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• 제14권7호
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• pp.49-58
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• 1997

In process planning for pocket machining, the selection of tool size, tool path, overlap distance, and the calculation of machining time are very important factors to obtain the optimal process planning result. Among those factors, the tool size is the most important one because the others depend on tool size. And also, it is not easy to determine the optimal tool size even though the shape of pocket is simple. Therefore, the optimal selection of tool size is the most essential task in process planning for machining a pocket. This paper presents a method for selecting optimal toos in pocket machining. The branch and bound method is applied to select the optimal tools which minimize the machining time by using the range of feasible tools and the breadth-first search.

• Journal of Electrical Engineering and Technology
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• 제11권6호
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• pp.1582-1589
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• 2016

In this paper the integration of Distributed Generation (DG) in radial distribution system is investigated by computing the optimal site and size of DG to be placed. An analytical expression based on equivalent current injection has been derived by utilizing topological structure of radial distribution system to find optimal size of DG to minimize losses. In the presented formulation, the optimal DG placement is obtained without repeatedly computing the load flow. The proposed formulation can be used to find the optimal size of all types of DGs namely Type-I, Type-II, Type-III and Type-IV DGs. The investigations are carried out on IEEE 33-bus and 69-bus radial distribution systems. The optimal DG placement results into reduction in active and reactive power losses and improvement in voltage profile of the buses.

• 소성∙가공
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• 제15권5호
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• pp.347-353
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• 2006

The delivery system such as sprue, runner and gate is a waste of resin in injection molding operation. In this study the reduction of runner size has been investigated using injection molding CAE softwares, Moldflow and Moldex3D, and commercial CFD Softwares, Fluent and Polyflow. To verify the computational results experiment was performed. There were three considerations in deciding optimal runner size in this study: minimum pressure at the gate that makes resin fully filled in the cavity, minimum runner size that compensates shrinkage of resin in the cavity, and frozen layer thickness formed in the runner during injection. Through the computer simulations the optimal runner size that satisfies those three considerations has been decided. Although the computational results among the softwares were slightly different, it was enough to predict the optimal runner size. The previous runner diameter was 8 mm and predicted optimal size was 5 mm. This was verified by injection molding experiment. Thus, the way of CAE application in deciding optimal runner size adapted in this study would be appropriated.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.363-366
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• 2006

The delivery system such as sprue, runner and gate is a waste of resin in injection molding operation. In this study the reduction of runner size has been investigated using injection molding CAE softwares, Moldflow and Moldex, and commercial CFD Softwares, Fluent and Polyflow. To verify the computational results experiment was performed. There were three considerations in deciding optimal runner size in this study: minimum pressure at the gate that makes resin fully filled in the cavity, minimum runner size that compensates shrinkage of resin in the cavity, and frozen layer thickness formed in the runner during injection. Through the computer simulations the optimal runner size that satisfies those three considerations has been decided. Although the computational results among the softwares were slightly different, it was enough to predict, the optimal runner size. The previous runner diameter was 8 mm and predicted optimal size was 5 mm. This was verified by injection molding experiment. Thus, the way of CAE application in deciding optimal runner size adapted in this study would be appropriated.

• 수산경영론집
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• 제43권1호
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• pp.1-9
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• 2012

Based on Clark and Munro's theory of dynamic optimization between fishery resources and production, this study is aimed to take an empirical analysis of optimal production level to the Danish Seine fishery under the sandfish stock rebuilding plan. For empirical analysis, it examined the optimal fish stock size, production and fishing effort levels and it also made an additional evaluation of optimal production changes on main variables by sensitivity analyses. When a 4% of the discount rate is assumed, the optimal sandfish production of Danish Seine fishery would be 3,049 t, and the sandfish optimal stock size is evaluated to be 19,016 t. In addition, the optimal fishing effort is estimated to be 4,368 days. Accordingly, to achieve the optimal production level, current fishing efforts should be reduced while the fish stock size should be increased up to the optimal level.

• 산업경영시스템학회지
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• 제18권35호
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• pp.39-46
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• 1995

This study is to find the optimal lot size method in the distribution system. In general, the lot size methods used in the distribution system is the same as the methods of the MRP system. The lot size methods used in this study are LFL, EoQ, LTC and POQ.. Resulting in case study, LTC is the optimal lot size method in the distribution system. In distribution system, VRP and VSP shall be investgated.

• The Korean Journal of Ecology
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• 제21권5_1호
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• pp.409-418
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• 1998

A molel study was conducted to determine the optimal sample size for the analysis of the aquatic insect community in a stream reach of the Pangtae Creek, Kangwon-do in October 1995 and may 1996. The results showed that the required minimum sample size varied and depended on the purposes of the community analysis. Acoording to the Species: Area Curve method, at least 16 Surber samplings ($30{\times}30cm$) were required in a stream reach in each spring and fall survey. The species diversity index did not vary significantly as the sample size increased. Based on the coefficient of variation analysis, the minimum sample sizes of 10 were required in order to compare seasonal differences of the community in the study area. Considering the static community structure of aquatic insects, including both species numbers and individual numbers of aquatic insects, 11 and 7 samplings were optimal sizes for the fall and spring survey, respectively. We concluded that 12 Surber samplings from 3 riffle-pool sequences (4 samplings at each riffle-pool sequence) would be required in a stream reach (length 1 km) to obtain reliable as well as cost efficient data. Our model showed that the optimal sample size should be determined by interactions between minimum sample size, the degree of data reliability, and cost efficiency.

• 전기학회논문지
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• 제57권4호
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• pp.551-559
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• 2008

Increase in power consumption can cause a serious stability problem of an electric power system without construction of new power plants or transmission lines. Also, it can generate large power loss of the system. In costly and environmentally effective manner to avoid constructing the new infrastructures such as power plants and transmission lines, etc, the distributed generation(DG) has paid great attentions so far as a solution for the above problem. Selection of optimal location and size of the DG is the necessary process to maintain the stability and reliability of existing system effectively. However, the systematic and cardinal rule for this issue is still open question. In this paper, the method to determine optimal location of the DG is proposed by considering power loss when the DG is connected to an electric power grid. Also, optimal size of not only the corresponding single DG but also the multi-DGs is determined with the proposed systematic approach. The IEEE benchmark 30-bus test system is analyzed to evaluate the feasibility and effectiveness of the proposed method.