• KIEAE Journal
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• 제5권1호
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• pp.11-18
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• 2005

The optimized HVAC system design in tall buildings enable owners to save unnecessary energy consumption and residents to have comfort environments. The purpose of this study is to develop design process for optimized HVAC system design in tall buildings. As basic researches, literature researches and case studies of HVAC system design in tall buildings were performed. Survey was processed among expert in the field and key considerations on HVAC system design were drew as conclusions. With these conclusions, studies were performed on effects of wind velocity, outdoor air temperature, and solar radiation that are main factors of load calculation in tall buildings. Finally, air-tightness and stack effect were analyzed and estimated by literature studies, field measurements and computer simulations.

• 콘크리트학회논문집
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• 제21권6호
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• pp.745-752
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• 2009

이 논문에서는 과산화수소를 사용한 경량기포콘크리트의 최적배합비를 제안하고 있다. 최적배합을 도출하기 위해 상용프로그램인 MINITAB을 사용하여 실험계획법을 적용하였다. 통계적 분석방법은 반응표면분석법 중 하나인 Box Behnken(B-B)계획법으로 하였다. 실험시 고려한 영향인자로는 단위시멘트량, 물시멘트비, 과산화수소비를 설정하였다. 분산분석에 따르면 경화상태에서 경량기포콘크리트의 물시멘트비와 과산화수소비는 절건밀도, 압축강도, 휨강도에 유의차가 있고, 단위시멘트량은 절건밀도에만 유의차가 있는 것으로 나타났다. 반응표면분석의 결과에서 과산화수소를 사용한 경량기포콘크리트의 최적배합비는 단위시멘트량 800 kg/$m^3$, 물시멘트비 44.33%, 과산화수소비 10%로 도출되었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.501-504
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• 1995

A Simultaneous optimal design of structural and control system of a semi-active suspension is applied on a helf-car model in this paper. Suspension stiffnesses and dampings are selected as structural design parameters and damping forces of variable dampers as controller parameters. Sence this optimization problem is of large discontinuous space, conventional exhaustive methods are not enough. So we here try out an approach using Genetic Algorithm for our problem. Through numerical simulation work, the performance of the simultaneously optimized system was tested and showed meaningful improvement over the partially optimized ones.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.523-524
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• 2009

본 연구는 최근 부각되고 있는 지속가능성능 평가를 내구성 설계에 도입하여 염해를 입은 RC구조 물의 목표 내용연수를 달성하기 위한 최적 보수 내구성 설계기법의 가능성에 대하여 살펴보고자 한다.

• 전자공학회논문지A
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• 제31A권4호
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• pp.106-115
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• 1994

This paper presents the design of a technology mapping system for optimizing delays of combinational and synchronous sequential logic circuits. The proposed system performs delay optimization for combinational logic circuits by remapping, buffering, and gate merging methods through the correct delay calculation in which the loading values are considered. To get time optimized synchronous sequential circuits, heuristic algorithms are proposed. The proposed algorithms reallocate registers by considering the critical path characteristics. Experimental results show that the proposed system produces a more optimized technology mapping for MCNC benchmarks compared with mis-II.

• 대한전기학회논문지
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• 제43권6호
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• pp.1020-1026
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• 1994

This paper presents a technique to optimize the shape of waveguide components in H-plane. The technique utilizes the numerical optimization process which employs the vector finite element method. In the optimization process, the sensitivity of an objective function with respect to design variables is computed by introducting adjoint variables, which makes the computation easy. The steepest descent method is then employed to update design variables. As a numerical example, an H-plane waveguide teejunction was considered to obtain optimized shape. Comparison between the initial and optimized shape was made.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1999년도 학술발표대회 논문집 제18권 2호
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• pp.237-242
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• 1999

In this study, a design method using plane actuator is developed to make new speaker system, whose shape is much thinner than that of conventional loudspeaker. Piezofilm(PVDF) is used as plane actuator of flat speaker. To avoid the distortion of sound radiated from flat speaker, the frequency response of radiated sound to be flat is taken as the design objective. The electrode pattern and orientation angle of piezofilm actuator is optimized to satisfy the design objective. The formulation is based on the coupled finite element and boundary element method. Genetic algorithm is used in the optimization process, which is useful in the optimization of discrete design variables. Frequency response with optimized piezofilm actuator is made flat enough to satisfy the design objective. For the enhancement of sound power, double-layered piezofilm actuators are also considered. The sound power with double-layered actuator becomes larger than that with single-layered actuator as expected.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.949-950
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• 2011

There are various ways of optimizing rotor design of Interior Permanent Magnet Synchronous Motors(IPMSM). In this paper, the best optimized design value was found by varying the Bridge thickness of PM in the rotor and changing Rib. The set design values were torque, 5 harmonics, 7 harmonics, and safety factor. Also, in order to make practical design value easily and quickly for optimization, Box-Behnken of Response Surface Method(RSM) method was used. Therefore, IPMSM resulted an optimized design model with high torque, low harmonics, and constant value of safety factor.

• 전기학회논문지
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• 제56권4호
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• pp.699-704
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• 2007

In this paper, optimized model was designed for the starting characteristic of the Single-Phase Line-Start Permanent Magnet Synchronous Motor by using the Design of Experiment. A field pole angle, thickness and distance from center axis of permanent magnet were selected as design factor. We executed the transient state characteristic analysis of 8 test models. The transient state characteristic analysis was executed by using the 2 dimensional Finite Element Method and the Time Difference Method. We checked the fact that the selected design factor affected starting characteristic of the Line-Start Permanent Magnet Synchronous Motor. Depend on this result we found the optimized design point by using the response optimization.

• 한국CDE학회논문집
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• 제17권4호
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• pp.246-252
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• 2012

The piping route of hydraulic hose is designed with avoiding interferences to surrounding components. However, in a real practice, the piping route is mostly decided with an expert's experiences on site due to the complexity of design. Thus, this paper proposes a design methodology of the optimized route of a hose. We use NURBS representation to describe the piping route, which is possible to be locally modified, and an energy minimization method is applied to avoid interferences to the surroundings. In other words, the NURBS curve describing a piping route is modified to meet the desired positions from minimizing the perturbation of the control points, and the strain energy of the curve is then optimized to make the curve natural. The proposed method is implemented and its feasibility is validated using the commercial CAD software, CATIA V5.