• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.98-106
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• 2021

The paper deals with comparative study on sensitivity analysis using various methods regarding to design of experiments for structure design of an active type DSF (Deck support frame) that was developed for float-over installation of offshore plant. The thickness sizing variables of structure member of the active type DSF were considered the design factors. The output responses were defined from the weight and the strength performances. Various methods such as orthogonal array design, Box-Behnken design, and Latin hypercube design were applied to the comparative study. In order to evaluate the approximation performance of the design space exploration according to the design of experiments, response surface method was generated for each design of experiment, and the accuracy characteristics of the approximation were reviewed. The design enhancement results such as numerical costs, weight minimization, etc. via the design of experiment methods were compared to the results of the best design. The orthogonal array design method represented the most improved results for the structure design of the active type DSF.

• Electronics and Telecommunications Trends
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• v.3 no.1
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• pp.3-23
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• 1988

VLSI 설계시 응용되는 CAD 기술중 배선과 관련된 내용에 대해 기술동향을 소개하였다. 특히, 미로법, 선분탐색법, 채널배선법에 대하여 연구의 발전과정, 연구내용, 현황 등을 상세히 기술하였으며, 반주문형 설계시 많이 이용되는 개략 배선법에 대해서도 기술하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.164-164
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• 2010

점광원 가정법은 광학계의 초점거리를 LED die 표면의 중심점으로 설정하고 LED 패키지의 발산형태는 이상적인 점광원으로 가정하여 설계하는 방법이며, 가초점 설계법은 focal smear라고 불리우는 초점영역의 가초점을 기준점으로 잡아 설계를 시행하는 방법이다. 실제 LED에서 빛이 발산하는 부분은 점광원이 아닌 부피를 가지고 있는 형태이기 때문에 점이외의 면에서 발생하는 오차와 가초점 영역 설정을 통한 설계는 결과에 오차를 발생시키게 된다. 따라서 구조 분석 실험 장비를 이용한 LED내부 구조를 분석한 후 이를 시뮬레이션 설계에 적용한 결과 기존 설계법에 비해 약 5%의 오차범위를 줄일 수 있었다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.2
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• pp.23-27
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• 2003

Using pervious two-dimensional reflector design method, the three-dimensional reflector design method is developed for extrusion molding HID specular reflector optical design, Using this method, a HID reflector for tunnel was developed and estimated its performance.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.6
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• pp.19-25
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• 2007

We studied prism design method for actual light source that have bulk in order to accomplish particular intensity distribution. When we know incidence angle and try to send ray to given direction, numerical formula that yields prism vertical angle, and then vertical angles were calculated sequentially. After analyzing problem that supposing to point light source, supplemented this and derived applicable prism design method on bulk light source. The intensity distribution and efficiency that came out by each design results were compared and analyzed, we got improved results through supplemented design method.

• Journal of the Korean GEO-environmental Society
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• v.20 no.11
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• pp.11-22
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• 2019

Limit state design (LSD) and allowable stress design (ASD) are two main types of soil nailing design methodologies. In the LSD method, stability is determined by applying individual coefficients to ground strength, working load and etc. The ASD method calculates the safety factor and compares it with the minimum safety factor to determine the stability. The global design trend of soil nailing system is changing from the ASD method to the LSD method. The design method in Korea still adopts the ASD philosophy while others mostly do the limit state design. In this study, four soil nail design methods, 'FHWA GEC 7' in U.S. (2015), 'Clouterre' in France (1991), 'Soil nailing - best practice guidance' in U.K. (2005), 'Geoguide 7' in Hongkong (2008), and 'Design guide for slope in construction work' in Korea (2016) were applied to the evaluation of the stability and the results were analyzed comparatively in brief. It is revealed that the design method of 'the overall stability of soil nail walls' in Korea is the most conservative and next those by FHWA, Clouterre and CIRIA become more conservative in order. However, the difference of results obtained from FHWA and Clouterre is negligible. Also, this study found out that efforts to improve domestic design criterion are needed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.15-18
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• 2003

무전극 형광램프는 발광하는 부분의 사이즈가 크고 광원의 특성상 점광원으로 볼 수 없기 때문에 효율적인 광학기구를 설계하기 어렵다. 특히 반사판 설계시 반사광이 램프로 재흡수 되는 것을 고려하여야 한다. 본 논문은 무전극 형광램프에 대하여 반사광이 램프로 재흡수 되는 것을 막고 효율을 높이며 목표배광에 맞출 수 있는 2차원 축대칭형 반사판 설계법을 제시하였다. 그리고 이 설계법의 문제점과 해결방법에 대하여 고찰하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.1
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• pp.37-43
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• 2010

In this paper, a reliability-based design optimization is developed for the topology design of linear structures using a performance measure approach. Spatial domain is discretized using three dimensional Reissner-Mindlin plate elements and design variable is taken as the material property of each element. A continuum based adjoint variable method is employed for the efficient computation of sensitivity with respect to the design and random variables. The performance measure approach of RBDO is employed to evaluate the probabilistic constraints. The topology optimizationproblem is formulated to have probabilistic displacement constraints. The uncertainties such as material property and external loads are considered. Numerical examples show that the developed topology optimization method could effectively yield a reliable design, comparing with the other methods such as deterministic, safety factor, and worst case approaches.

• The Korean Journal of Applied Statistics
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• v.26 no.4
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• pp.581-594
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• 2013

A group sequential design can end a clinical trial early if a confirmed efficacy or a futility of study medication is found during clinical trials. Adaptation can adjust the design of clinical trials based on accumulated data. The key to this methodology is considered to control the overall type 1 error rate while maintaining the integrity of clinical trials. The estimation would be more complex and the sample size calculation will be more difficult if the clinical trials have repeated measurement data. Lee et al. (2002) suggested a repeated observation case by using the independent increments properties of the interim test statistics and investigated the properties of the proposed confidence interval based on the stage-wise ordering. This study extend Lee et al. (2002) to adaptive group sequential design. We suggest test statistics for the adaptation as redesigning the second stage of clinical trials and induce the stage-wise confidence interval of parameter of interests. The simulation will help to confirm the suggested method.

• International Journal of Highway Engineering
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• v.9 no.3
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• pp.91-100
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• 2007

The most important thing for driver's safety on the road is equipment of crash cushion as a vehicle protection safety facility. But development of crash cushion is defective because there's no rational and reality way of design. And also without an alternative plan, it rely on crash test hereby it suffers a great economic loss and wastes time. This study that uses data of cash test proves the suitability of single degree of freedom which considers the safety of passengers about three-dimensional complicated Crash Analysis. As the study analyzes the conduct of crash cushion, it want to develop the effective method of design on Single Degree of Freedom Crash Cushion. And it presents the way of crash cushion design through making a crash analysis model with single degree of freedom. To verify the validness of the crash cushion plan, with single degree of freedom plan, we make the level CC2 crash cushion and execute the crash test. A performance test brings satisfied result and a plan of single degree of freedom crash cushion is proven as an one of the way to be a good system which can design crash cushion.