• 조명전기설비학회논문지
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• 제27권9호
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• pp.62-73
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• 2013

In this paper, a new linear synchronous motor - permanent magnet double-sided synchronous motor with perpendicular arrangement (PMDLSM), was proposed. It was designed to account for the drawbacks of conventional linear motors, such as the normal force and end effects. The detent force and the thrust were analyzed for different combinations of primary core modules and magnet poles of the machine, and the optimum combination was made. The characteristics of the perpendicular PMDLSM were analyzed by finite element method, and the experiments agreed well with the analysis.

• 한국건축시공학회지
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• 제12권3호
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• pp.358-368
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• 2012

On most construction sites, the arrangement of tower cranes is decided by site engineers based on their own experience, which can cause cost overruns and delays in the lifting work. Although many researchers have conducted studies on tower crane arrangement using computer modeling and knowledge-based expert systems as well as mathematical models, no research has aimed to develop an algorithm to identify an optimum solution among several alternatives for installation areas of tower cranes satisfying the conditions of lifting work. The objective of this study is to develop an automatic arrangement algorithm for tower cranes used in high-rise apartment construction. First, as a new concept, a possible installation area of tower cranes was suggested. Second, after proposing several alternatives based on the installation points suggested in this study, an algorithm analyzing the economic feasibility of tower cranes was developed considering the rental, installation and removal costs. Third, a case study was conducted to prove the validity of the developed algorithm for selecting and installing an effective set of tower cranes at minimum cost.

• 대한조선학회논문집
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• 제34권4호
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• pp.84-90
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• 1997

무개형 콘테이너 선박에 대한 구조 설계 과정에 최적화 기법을 적용하여 최적 구조 시스템을 개발하였다. 중앙 단면 설계 기법으로는 L.R rules을 이용하였고 목적 함수는 중앙 단면 모든 종강도 부재 단면적의 합, 즉 최소 중량을 선택하였다. 최적화 기법으로는 직접탐색법에 SUMT방법을 결합시켜 사용하였다. 최소 중량 설계를 수행한 결과 실적선과 비교하여 8.0%의 중량감소를 보인 최적화 설계를 도출하였다.

• 한국터널지하공간학회 논문집
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• 제18권6호
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• pp.569-579
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• 2016

국내 터널 갱구사면에 안정성을 확보하기 위한 사면보강은 앵커, 쏘일네일 및 록볼트 등을 이용한 다양한 공법이 사용되고 있다. 갱구 사면보강공법 및 보강재 배치, 보강재 길이 등을 선정하기 위해서는 시행착오법 등 시간이 많이 소요되기도 하며, 최적조건의 상태가 선정되었는지에 대한 검증이 쉽지 않은 경우도 발생한다. 본 연구에서는 FLAC3D 프로그램에 내장된 FISH 언어를 사용해서, 차분진화 알고리즘(DEA)을 적용한 최적화기법을 개발하였다. 갱구사면 보강공법 중에 쏘일네일링 공법에 대한 데이터베이스를 구축한 후, FLAC3D 해석을 통한 안전율 기반의 최적보강배치 계획을 선정할 수 있도록 하였다. 수치해석 결과, 완전조합(FC)에 비해서 DEA 기반의 최적화기법이 해석회수가 8배 정도 감소함을 확인하였다. 갱구 사면보강 설계 시 개발된 시스템을 활용하면, 최적보강배치 계획을 상대적으로 쉽게 선정할 수 있을 것으로 기대된다.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2001년도 춘계학술발표대회 논문집
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• pp.117-120
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• 2001

This study is a preliminary research to develop design principles for environmentally friendly housing. The purposes of study are to investigate the literatures related passive design for summer and theory of ventilation, to analyze the indoor airflow patterns in traditional Korean house during summer, and to propose the design factors for effective passive cooling system. The analysis for airflow patterns was focused on the ‘An bang’and the ‘Dae Chung’in the ‘An Chae’of a traditional house located in Seoul. Field measurements of air temperature and air velocity were carried out at 30 different measuring points with 8 different window-opening conditions. The measurements were taken on the hottest summer days in August 2000. It is concluded that from an environmentally friendly standpoint design factors to control indoor thermal environment by a passive cooling system during the summer are as follows; ceiling structure has thermal performance like a time-lag effect, optimum height and length of eaves which can prevent sunlight and divert airflow toward the sitting level, building arrangement acceptable the prevailing wind, strategic window arrangement which makes cross ventilation possible (especially north-south) at the sitting level, window opening condition which is possible to intersect two cross-ventilation stream at the main living areas, northward windows remaining in shade to create the air pressure difference, and planning building shape like a bracket that has optimum width and depth.

• Journal of Welding and Joining
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• 제12권3호
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• pp.71-81
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• 1994

Laser cutting is experiencing a rising worldwide acceptance in the industry. Expert systems are necessary for the systematic arrangement and searching of experimental data existing in journal papers, job handbooks, etc.. This paper proposes an expert system for the selection of the appropriate laser cutting variables from the available database. Optimum cutting conditions according to the given cutting velocity were searched and qualitative comments which are difficult to be used as database variables were shown at each velocity using the binary and fuzzy inference. These comments could be informative to unskilled operators of the laser cutting process. Typical cutting conditions of the mild steel and stainless steel were included and the working range and quality variations were displayed graphically. The proposed algorithm was implemented in an IBM compatible personal computer as an expert system for CO$_{2}$ laser cutting to derive the optimum cutting conditions by using the turbo prolog.

• 설비공학논문집
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• 제11권5호
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• pp.700-708
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• 1999

The optimum dimple shape and arrangement in the channel of a plate heat exchanger with staggered dimples are proposed in this study. Four important geometric parameters are selected as design variables, the pressure drop and heat transfer characteristics are examined in the channel of plate heat exchangers. The optimization is accomplished by minimizing the global criterion function which consists of the correlations of Nusselt number and pressure drop. The optimum geometric parameters were found at the dimensionless dimple distance (L) of 0.272, the dimensionless dimple angle ($\beta$) of 0.44, the dimensionless dimple volume (V) of 0.106 and the dimensionless dimple pitch (G) of 0.195. It is found that the heat transfer and pressure drop of the optimum model are increased by approximately 227.9% and 32.9%, respectively, compared to those of the base model.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.639-644
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• 2006

The outlet temperature of gas cooler has a great effect on the efficiency of carbon dioxide heat pump system. In order to obtain a small approach temperature difference at gas cooler, near-counter flow type heat exchanger has been proposed, and larger heat transfer area is demanded. The optimum design of gas cooler involving the analysis of trade-offs between heat transfer performance and cost is desirable. In this study, the effects of geometric parameters, such as the circuit arrangement, tube diameter, transverse tube spacing, longitudinal tube spacing and the number of tube rows and fin spacing on the performance of heat transfer were investigated using the developed model. This study suggested various simulation results for optimum designs of gas cooler.

• 반도체디스플레이기술학회지
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• 제10권4호
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• pp.101-106
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• 2011

There are various methods in the flat panel display manufacture. The cost reduction effect is very big in case of using the screen printing method. The screen printing method is much used in the process of forming PDP barrier and can apply to the process of arranging the pillars for maintaining the vacuum gap of the vacuum glazing panel. The pillar which is one of the core elements for comprising vacuum glazing maintains the vacuum gap overcoming the vacuum pressure difference with the atmospheric pressure generated in vacuum glazing. At the same time, the deformation phenomenon by vacuum pressure is relived. In this paper, by using FEM about three considered in the pillar design and arrangement kinds of limiting factors, the simulation was performed. The pillar optimum arrangement method at within the maximum allowable tensile stress and heat transfer coefficients according to the arrangement try to be presented based upon the analyzed result data review and this validity tries to be verified by FEM.

• 대한조선학회논문집
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• 제47권6호
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• pp.792-802
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• 2010

A plastic analysis method is commonly used in ship and offshore structural system to utilize the ultimate strength. In this paper, the basic principle of plastic analysis method is applied to ship grillages such as transverse oil-tight bulkheads. The main emphasis is placed on the optimum arrangement of grillage system to give minimum weight. Additional parametric study is carried out to find the effect of various arrangement of grillage system. The above methods are applied to oil-tight bulkhead design, and results are compared with the existing one.