• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2384-2389
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• 2007

The 2nd order response surface method (RSM) has been carried out to get optimum thermal design for enhanced heat transfer on square channel with bleed holes. The RSM was used as an optimization technique with Reynolds-averaged navier-stokes equation. Turbulence model for heat transfer analysis used RNG k-epsilon model. The wall function used enhanced wall function. Numerical local heat transfer coefficients were similar to the experimental tendency. Two design variables such as attack angle of rib (${\alpha}$), rib pitch-to-rib height ratio (p/e) were chosen. Operation condition considered bleeding ratio per bleed hole ($BR_{hole}$). A response surface were constructed by the design variables and operation condition. As a result, adjusted $R^2$ was more than 0.9. Optimization results of various objective function were similar to heat transfer in channel with and without bleed flow. But friction factor was lower than channel without bleed flow.

• 대한조선학회 특별논문집
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• 대한조선학회 2005년도 특별논문집
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• pp.144-150
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• 2005

The size of ship is being larger than the past in the shipping industry thanks to the increased quantity of goods transported by ship. Therefore, HHIC (Hanjin Heavy industries & Construction co., LTD) invented innovative construction method, so called 'DAM', to build a ship which is longer than the length of the HHIC's dry dock. On Erection at the sea by the application of DAM Method, Squeezing & Detachment of A/F film may occur as a result of the wave and the constriction between A/F film pre-applied on the side shell and DAM's Rubber Packing. Thus, the test for finding the minimum curing time of A/F film was performed to protect Squeezing & Detachment of A/F film on the hull. To verify the soundness of paint and to find the optimum condition during the erection period of the DAM, laboratory test was carried out under no immersion condition through the application of various coatings on the Rubber Packing. And two methods were selected from the results of laboratory test for actual MOCK-UP Test. In addition, the test for the film profile per temperature of silicone A/F coat and the film Squeezing was performed.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.329-334
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• 2006

Rail clamps are mechanical components installed to fix the container crane to its bottoms from wind blast or slip. Rail clamps should be designed to survive the harsh wind loading condition. In this study, the jaw structure that is one part of wedge-typed rail clamp is optimized, considering strength under the severe wind loading condition. According to the classification of structural optimization, the structural optimization of a jaw belongs to shape optimization. In the conventional structural optimization methods, they have difficulties in defining complex shape design variables and preventing mesh distortions. To overcome the difficulties, the metamodel using kriging interpolation method is introduced, replacing true response by approximate one. This research presents the shape optimization of a jaw using iterative kriging interpolation models and simulated annealing algorithm. The new kriging models are iteratively constructed by refining the former kriging models. This process is continued until the convergence criteria are satisfied. The optimum results obtained by the suggested method are compared with those obtained by the DOE (design of experiments) and VT (variation technology) methods built in ANSYS WORKBENCH.

• 대한기계학회논문집
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• 제14권5호
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• pp.1059-1068
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• 1990

본 연구에서는 4변이 단순지지되고 보강재가 등간격으로 조밀하게 배치된 편 면직교보강평판에 조합하중이 작용하는 경우 최소중량화에 따른 최적설계변수들을 비 선형 최적화기법인 미분벡터유영법(gradient projection method)에 의하여 산정한다. 설계제한조건으로 전체좌굴응력, 평판및 보강재의 국부좌굴응력, 각부의 항복응력제한 그리고 설계변수들의 상, 하한치의 제한등을 설정하고 전체좌굴에 대한 지배방정식으 로 등가의 직교이방성 평판의 좌굴에 관한 평형방정식을 사용한다. 직교 보강의 경 우 기존연구결과와 비교, 분석하여 본 해석의 유용성을 입증하고 조합하중의 작용에 따른 대칭경사보강의 효율성도 검토한다.

• 센서학회지
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• 제6권3호
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• pp.245-251
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• 1997

제세동기는 심장마비가 진행되는 동안 발생하는 심장의 '심실세동'으로 알려진 발작적인 떨림을 제거하기 위해서 환자의 심장에 전기적 충격을 주는 의료기기이다. 본 연구에서는 제세동기에 개발 및 성능개선시 고려되어야 할 전기회로 각 요소 값들을 컴퓨터 시뮬레이션을 통하여 결정하였고, 이를 근거로 하여 제세동기를 개발하였으며, 제세동기 분석기를 통하여 개발된 제세동기의 성능을 시험하였다. 구체적으로, 심장의 심실세동을 제거하기 위하여 필요한 에너지 레벨, 전류의 크기, 횡흉부 저항 등과 같은 요소들간의 관계를 구명하였고, 제세동기 전기회로의 성능을 예측 분석하여 최적의 방전파형을 얻기 위한 회로소자의 매개변수 값 범위를 결정하였으며, 제세동기 성능분석기를 이용하여 개발된 제세동기의 성능을 시험하였다.

• 한국식품영양과학회지
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• 제32권4호
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• pp.544-548
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• 2003

매실을 사용하여 초산을 생산하기 위하여 알콜 농도, 발효온도, 당 농도의 3변수와 5수준의 fractional factorial design에 의하여 RSM computer program을 사용하여 최적 발효조건을 조사하였다. 초산함량에 대한 회귀분석결과, $R^2$는 0.9462로 높게 나타났다. 알콜 농도 8.76%, 발효 온도 26.27$^{\circ}C$, 당농도 8.42%에서 발효하는 것이 초산 생성을 위하여 가장 양호하였으며, 이 조건에서의 초산 생성 예상치는 3.23%이었다.

• 한국정밀공학회지
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• 제23권6호
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• pp.136-142
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• 2006

Optimization of the aircraft panel assembly constructed by skin and stringers is investigated. For the design of panel assembly of the aircraft structure, it is necessary to determine the best shape of the stringer which accomplishes lowest weight under the condition of no instability. A panel assembly can fail in a variety of instability modes under compression. Overall modes of flexure or torsion can occur and these can interact in a combined flexural/torsion mode. Flexure and torsion can occur symmetrically or anti-symmetrically. Local instabilities can also occur. The local instabilities considered in this paper are buckling of the free and attached flanges, the stiffener web and the inter-rivet buckling. A program is developed to find out critical load for each instability mode at the specific stringer shape. Based on the developed program, optimization is performed to find optimum stringer shape. The developed instability analysis program is not adequate for sensitivity analysis, therefore RSM (Response Surface Method) is utilized instead to model weight and instability constraints. Since the problem has many local minimum, Genetic algorithm is utilized to find global optimum.

• 한국식품조리과학회지
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• 제23권6호
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• pp.954-960
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• 2007

The study was designed to determine optimum extraction conditions, by the factorial design of 3 variables and 3 levels using an a RSM program. To determine the optimal conditions for the extraction of black tea with chamomile, the experimental design was applied. The independent factors were the extraction temperature ($60^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$), extraction time (2 min, 4 min, 6 min), and chamomile addition (0.3%, 1.0%, 1.7%). By the RSM (response surface methodology) analysis of the black tea with chamomile extraction, we found that the extraction temperature greatly affected the extraction yield, brix, pH, and reducing sugar, caffeine, theobromine and theophillin contents. The optimum extraction time, temperature, and chamomile content were 4 min, $90^{\circ}C$, and $1.6{\sim}1.7%$, respectively.

• 한국콘텐츠학회논문지
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• 제11권8호
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• pp.468-474
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• 2011

연료전지에 사용되는 백금촉매 제조 공정상의 변수로서 환원제를 사용 하였다. 환원조절 횟수, 환원온도, 환원제의 양 그리고 공정시간의 네 가지의 제어인자에 변화를 주어 입자의 크기와 ICP 수율 등의 촉매 구조에 관한 최적화의 평가를 위해 six sigma 의 design of experiment 기법을 사용하여 각각의 변수간의 최적점을 확인해 보았다. 부분요인배치를 통해 입자크기 2.2nm 이하와 ICP수율 75% 이상의 촉매제조를 위하여 도출된 결과로서 주된 제어인자는 환원 시간과 환원 온도로서 밝혀졌고 각 변수의 최적 조건으로서는 환원조절횟수 1회, 환원온도 $67-88^{\circ}C$, 환원제의 양 0.5ml 그리고 10분의 공정시간에서 최적화가 이루어졌다.

• Korean Journal of Acupuncture
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• 제25권3호
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• pp.15-27
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• 2008

Objectives : The objective of the current study is to optimize an acupoint electrical property measurement system by using the procedures and strengths of the Taguchi method. Methods : Taguchi method was applied in the optimization of the acupoint electrical property measurement system, as in the following steps: (1) determine evaluation index; (2) execute the 1st gage R&R; (3) identify controllable and uncontrollable factors; (4) design Taguchi crossed array layout; (5) execute experiments according to trial conditions; (6) analyze testing results; (7) determine optimum run; (8) execute the 2nd gage R&R; (9) confirm optimum run. Results : The results showed that electrodes with larger diameter and efferent electric current, with music played, can produce the larger different electrical conductivity between the acupoints and the non-acupoints under various conditions. Taguchi process optimization improved repeatability and reproducibility of the acupoint electrical property measurement system. Conclusions : In the optimized condition, repeatability and reproducibility of the acupoint electrical property measurement system was acceptable.