• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.486-486
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• 2006

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2001년도 제2회 생물정보학 국제심포지엄
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• pp.103-127
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• 2001

Gene expression studies require statistical experimental designs and validation before laboratory confirmation. Various clustering approaches, such as hierarchical, Kmeans, SOM are commonly used for unsupervised learning in gene expression data. Several classification methods, such as gene voting, SVM, or discriminant analysis are used for supervised lerning, where well-defined response classification is possible. Estimating gene-condition interaction effects require advanced, computationally-intensive statistical approaches.

• 대한산업공학회지
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• 제29권2호
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• pp.179-189
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• 2003

Gate poly-silicon critical dimension is a prime characteristic of a metal-oxide-semiconductor field effect transistor. It is important to achieve the uniformity of gate poly-silicon critical dimension in order that a semiconductor device has acceptable electrical test characteristics as well as a semiconductor wafer fabrication process has a competitive net-die-per-wafer yield. However, on gate poly-silicon critical dimension, the complexity associated with a semiconductor wafer fabrication process entails hierarchical variance components according to run-to-run, wafer-to-wafer and even die-to-die production unit changes. Specifically, estimates of the hierarchical variance components are required not only for disclosing dominant sources of the variation but also for testing the wafer-level uniformity. In this paper, two experimental designs, a two-stage nested design and a randomized complete block design are considered in order to estimate the hierarchical variance components. Since gate poly-silicon critical dimensions are collected from fixed die positions within wafers, a factor representing die positions can be regarded as fixed in linear statistical models for the designs. In this context, the two-stage nested design also checks the wafer-level uniformity taking all sampled runs into account. In more detail, using variance estimates derived from randomized complete block designs, Duncan's multiple range test examines the wafer-level uniformity for each run. Consequently, a framework presented in this study could provide guidelines to practitioners on estimating the hierarchical variance components and testing the wafer-level uniformity in parallel for any characteristics concerned in semiconductor wafer fabrication processes. Statistical analysis is illustrated for an experimental dataset from a real pilot semiconductor wafer fabrication process.

• 한국문헌정보학회지
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• 제25권
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• pp.325-341
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• 1993

The experimental method, when carried out properly, is the most powerful way of seeking answers to research questions. The purpose of this study is to provide practical and theoretical insights as well as to discuss technical skills needed to design and implement the experimental research in library and information science. The levels of empirical research methods, the logic and types of the experimental designs, the application status of the experimental methods through content analysis of the published papers, and strategies to plan the research and to collect and analyze data are examined. This study also brings suggestions how experimental research can be made more meaningful and puts emphasis on the need of the research method education in library and information science field.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
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• pp.580-593
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• 1998

2차 반응표면분석을 위한 부분합성계획은 실험 비용이 많이 들거나, 실험 자체가 어려워서 시간의 소비가 많은 경우, 실험오차의 독립추정이 가능할 때 효과적이다. 반응표면분석에서는 회전성과 기울기 회전성을 만족하는 것이 중요하다. 따라서 본 논문에서는 회전성과 기울기 회전성의 관점에서 부분합성계획을 살펴보고 또한 인자의 수와 중심점의 수가 변함에 따라서 어떤 a(중심에서 축점까지의 거리)의 값이 최적의 실험계획이 되도록 하는지를 연구하였다.

• Child Health Nursing Research
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• 제23권3호
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• pp.300-311
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• 2017

Purpose: There are many forest and outdoor programs being offered but systematic reviews of effects are lacking. This study was done to identify content, format, and strategies of forest therapy programs for elementary school students. Methods: Literature search using keywords in English and Korean was performed using 6 electronic databases in December 2016. Search participants were elementary school students and interventions conducted in the forest. Seventeen forest therapy studies were selected for evaluation. Risk of Bias Assessment tool for non-randomized study was used for quality assessment. Results: All studies were quasi-experimental designs. Forest therapy programs included various activities in forests such as experience of five senses, meditation in the forest, walking in the forest, ecological play, observation of animals and insects. All studies used psychosocial health variables and forest healing programs had positive effects on sociality, depression, anxiety, self-esteem, stress, aggression, anger, and school adjustment. Limitations of these studies were vague reporting of the study, lack of ethical review and rigorous research designs. Conclusion: Forest therapy for elementary school child can be an effective way to improve psychosocial health. Future studies with rigorous study designs are needed to assess long-term effects of forest therapy on physical and psychosocial health.

• International Journal of Fluid Machinery and Systems
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• 제3권2호
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• pp.150-159
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• 2010

Laidback fan shaped film-cooling hole is formulated numerically and optimized with the help of three-dimensional numerical analysis, surrogate methods, and the multi-objective evolutionary algorithm. As Pareto optimal front produces a set of optimal solutions, the trends of objective functions with design variables are predicted by hybrid multi-objective evolutionary algorithm. The problem is defined by four geometric design variables, the injection angle of the hole, the lateral expansion angle of the diffuser, the forward expansion angle of the hole, and the ratio of the length to the diameter of the hole, to maximize the film-cooling effectiveness compromising with the aerodynamic loss. The objective function values are numerically evaluated through Reynolds- averaged Navier-Stokes analysis at the designs that are selected through the Latin hypercube sampling method. Using these numerical simulation results, the Response Surface Approximation model are constructed for each objective function and a hybrid multi-objective evolutionary algorithm is applied to obtain the Pareto optimal front. The clustered points from Pareto optimal front were evaluated by flow analysis. These designs give enhanced objective function values in comparison with the experimental designs.

• JSTS:Journal of Semiconductor Technology and Science
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• 제15권5호
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• pp.437-444
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• 2015

In simulation-based circuit optimization, many simulation runs may be wasted while evaluating infeasible designs, i.e. the designs that do not meet the constraints. To avoid such a waste, this paper investigates the use of support vector machine (SVM) classifiers in predicting the design's feasibility prior to simulation and the optimal selection of the SVM parameters, namely, the Gaussian kernel shape parameter ${\gamma}$ and the misclassification penalty parameter C. These parameters affect the complexity as well as the accuracy of the model that SVM represents. For instance, the higher ${\gamma}$ is good for detailed modeling and the higher C is good for rejecting noise in the training set. However, our empirical study shows that a low ${\gamma}$ value is preferable due to the high spatial correlation among the circuit design candidates while C has negligible impacts due to the smooth and clean constraint boundaries of most circuit designs. The experimental results with an LC-tank oscillator example show that an optimal selection of these parameters can improve the prediction accuracy from 80 to 98% and model complexity by $10{\times}$.

• 한국지능시스템학회논문지
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• 제19권6호
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• pp.814-820
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• 2009

일반 12-키 휴대폰 키패드의 알파벳 배치 방식은 한두 가지로 통일되어 있다. 대개 하나의 키에 여러 개의 알파벳을 순서가 있게 배치한다. 영문을 입력할 때 우리나라를 포함한 비영어권 국가에서는 대부분 멀티탭(multi-tap) 방식을 사용하는데, 이 멀티탭 방식에서는 같은 키를 반복해서 눌러야 다음 알파벳을 입력할 수 있게 된다. 본 논문에서는 멀티탭 방식으로 다양한 상황의 영문 데이터를 입력할 때 필요한 키 누름 횟수를 최소화하는 키패드를 디자인한다. 제안한 유전 알고리즘을 이용해 최적의 키패드를 디자인할 수 있었다. 키의 개수는 최소 8개에서 최대 12개까지를 사용하며 알파벳 순서를 유지한 것과 그렇지 않은 키패드 디자인에 대해 다양하게 실험하였고, 결과적으로 모든 경우에 개선된 키패드 디자인을 도출 해냈다.

• 한국실내디자인학회논문집
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• 제18권3호
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• pp.84-92
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• 2009

Sociological, technical, and organizational changes have affected the culture of business in many ways. These changes are now encouraging new concepts in the workplace environment such as emotional approaches for a more creative and humanistic workplace let alone enhancing image of the company. The aim of this study is to understand current situations of common office areas and serve as a stepping stone for designing more creative and stimulating work environments. The study first examines concepts of new office designs in our modem society, then defines categories such as territorial fuzziness, eco-friendly, fun and play. Secondly, by using content analysis as research tool the researchers have investigated how the conceptual categories and detailed design presentation methods are shown in workplace designs in Korea. Scope of study is limited to 39 office design projects from 2002-2008 presented in the Korean monthly magazine 'Interiors'. As results. territorial fuzziness was found to be most popular method while play the least. For application wise, meeting rooms, rest area and hallways were places where these concepts appear the most. Even though, these new approaches in office designs can be found in our domestic offices, still more experimental and active approach seems to be needed.