• 한국산업융합학회 논문집
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• 제10권4호
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• pp.227-233
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• 2007

In case of design of a rectifier to supply high current, To select switching frequency of semiconductor switches affect absolutely the design of the LC filter value in an power conversion circuit. The conventional rectifier by using MOSFET is no use in high current equipments because of small drain-source current. To solve this problem, this paper proposes to design of high capacity rectifier by parallel driving of MOSFET in the single half bridge DC-DC converter. This method can be able to develop high current rectifier by distributed drain-source current. The proposed scheme is able to expect a decrease in size, weight and cost of production by decreasing the LC filter value and increasing maximumly the switching frequency. The validity of the proposed parallel driving strategy is verified through computer-aided simulations and experimental results.

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2005년도 춘계 학술발표대회 논문집
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• pp.252-253
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• 2005

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1065-1072
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• 2010

Case studies published in Korea versus the low ground fault is applied on the bridge based on theory or experience in the design of pile bearing capacity by the value of the expression is designed to conduct field tests Disclosure Load bearing capacity value, the result of applying a reasonable construction cost savings of approximately 10 eokyeowon Has, in the design of site investigation was insufficient to require additional efforts. Apply the appropriate value from the extra support in the design of accurate ground survey and air speed to cut the budget and social technology can ensure the reliability was unknown.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.659-662
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• 2006

플랜트 산업은 2004년도 기준 해외 건설 수주액의 70%를 차지하는 매우 중요한 산업이다. 플랜트 산업의 기술력은 일부 시설관련 상세설계와 시공부문의 경쟁력을 확보한 상태이다. 그러나 플랜트 산업 가운데 고부가가치 창출이 가능한 기획, 기본설계 기술이 미흡하여 기술력 향상이 필요하다. 따라서 고부가가치 창출이 가능한 기획, 기본설계 기술 경쟁력을 향상시키기 위하여 플랜트 설계를 위한 표준코드의 문제점 및 개선방향을 제시하고자 한다.

• 대한안전경영과학회지
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• 제19권4호
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• pp.209-219
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• 2017

Logistics companies want to be competitive companies in fierce logistics market and are worrying about securing of differentiated competitiveness for it. The standards judging if logistics industry maintains the competitiveness are based on the satisfaction of users due to the well-established service system that can response not only economic feasibility of logistics costs such as transportation costs, storage costs, unloading charges, information costs, etc. but also diversity and upgradability of logistics needs. Therefore, this study focuses on seeking of service quality improvements with VBSD(Value Based Service Design) model focusing on customer value factors based on Kano model and QFD based service design approach from angles of customer value improvement and service costs reduction.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 B
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• pp.509-511
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• 1998

Design of fuzzy logic controllers encounters difficulties in the selection of optimized membership function and fuzzy rule base, which is traditionally achieved by tedious trial-and-error process. In this paper We proposed a new method to generate fuzzy logic controllers throught genetic algorithm(GA). The controller design space is coded in base-7 strings chromosomes, where each bit gene matches the 7 discrete fuzzy value. The developed approach is subsequently applied to the design of proportional plus integral type fuzzy controller for a do-servo motor control system. It was presented in discrete fuzzy linguistic value, and used a membership function with Gaussian curve. The performance of this control system is demonstrated higher than that of a conventional PID controller and fuzzy logic controller(FLC).

• 설비공학논문집
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• 제27권12호
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• pp.639-644
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• 2015

This study reviews the discharge coefficient for thermal buoyancy natural ventilation through experimentation. We measure the air velocity at the outlet, which is needed to derive the discharge coefficient and to compare with the theoretical value. When a temperature difference exists between the inside and outside of the building, the measured discharge coefficient differs from the theoretical value with a maximum difference of 12%. The size and position of the openings have little effect on the discharge coefficient. For practical application, the theoretical discharge coefficient can be used with little modification.

• Structural Engineering and Mechanics
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• 제6권5호
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• pp.543-554
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• 1998

Space truss structures may be fabricated in any of several common grid configurations. With different configurations, the truss performance varies considerably affecting both its competitiveness and suitability for specific applications. The work presented in this paper is an assessment of the most commonly adopted truss configurations and their effect on truss characteristics such as the stiffness/weight value, member stress distribution, number of joints and members, degree of redundancy and cost. The study is parametric and covers wide variations of truss aspect ratios, boundary conditions and span/depth ratios. The results of this study could be of significant value to the design of space truss structures.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.1491-1492
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• 2010

• 한국정밀공학회지
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• 제29권6호
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• pp.607-612
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• 2012

The wear problem of wheel flange occurs at sharp curves of rail. This paper proposes a procedure for optimum design of a wheel profile wherein flange wear is reduced by improving an interaction between wheel and rail. Application of optimization method to design problem mainly depends on characteristics of design space. This paper compared local optimization method with global optimization according to sensitivity value of objective function for design variables to find out which optimization method is appropriable to minimize wear of wheel flange. Wheel profile is created by a piecewise cubic Hermite interpolating polynomial and dynamic performances are analyzed by a railway dynamic analysis program, VAMPIRE. From the optimization results, it is verified that the global optimization method such as genetic algorithm is more suitable to wheel profile optimization than the local optimization of SQP (Sequential Quadratic Programming) in case of considering the lack of empirical knowledge for initial design value.