• 한국의류산업학회지
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• 제16권1호
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• pp.43-54
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• 2014

In textile industry, needs for various weave drafts have been increased to produce high qualified textile goods. One of disadvantages of traditional textile industry was spending time and money on manual sampling. Nowadays, however, weave draft design and sampling using CAD programs reduce these consumption efficiently. Therefore, this study aimed to provide high qualified woven fabrics by weave draft designs influenced by geometric patterns. First, We analyzed geometric patterns, except for dot, stripe, and checks, in fashion collections from 2009 to 2014 S/S. Then, based on these analyses, design concepts were decided. Third, weave drafts influenced by geometric patterns were designed with weave CAD program, TEX PRO 10.0 by Youngwoo CNI inc. Forth, We simulated fabrics woven by new drafts using CAD programs, depending on fibers, yarns, density of woven, colors, and finishes. Unclassified geometric patterns would be expressed by small size patterns that influenced by retro moods, square patterns with various color variation, zigzag lines, and pieces of puzzles. Three design concepts were decided as greenness, neoclassic, and romantic chic. Thus, geometric patterns for printing were created as drafts for general looms, and one repeat of each draft were provided. According to the design concepts, we designed 13 fabrics with 4 geometric patterns weaving drafts. All Drafts were designed with CAD programs. Finally, same drafts were simulated as woven fabrics for both S/S and F/W seasons by changing each element, such as fiber, yarns, density, colors, and finishes.

• 대한수학교육학회지:학교수학
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• 제8권4호
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• pp.441-463
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• 2006

본 연구에서는, 초등학생들이 생활 주변의 자료수집이 필요한 상황에서 자료를 수집하기 위하여 어떤 설계를 하여 표본을 설정하는지, 조사한 자료를 효율적으로 분석하기 위하여 표 또는 그래프 등의 도구를 어떻게 이용하고 어떠한 결과를 얻는가를 알아보았다. 이를 위하여 자료 수집이 필요한 상황에서 자료 수집과 설계 및 조사에 관하여 학생들이 논의와 시행착오를 통하여 찾아가도록 지도 및 관찰하였다. 그래서 통계 자료를 정리하고 결과분석을 하는 수업을 통해서 초등학교 6학년 학생들의 표본 개념의 이해 수준이 향상되고, 자료 분석을 위하여 표와 그래프를 더 잘 이용하게 됨을 확인하였다.

• 지역사회간호학회지
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• 제21권4호
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• pp.532-540
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• 2010

Purpose: The purpose of this study was to compare similarities and differences in research trends for community health nursing between Korea and Japan. Methods: Comparison was made in terms of research design, data collection and sampling method, and key concepts from community health nursing research by literature review. We analyzed original articles from representative Journals covering community health nursing research from 2004 to 2008. Results: We found that research design was quite different between the two countries. Quantitative research design was dominant in Korea, while qualitative and qualitative research designs were used equally in Japan. In particular, outcome research was found only in Korean papers. Conclusion: Based on the comparison, the following recommendations are suggested related to the strengths and weaknesses of research concepts and methods observed in each country. It is suggested that future collaboration should be undertaken especially to improve the diversity of research design and method. More diverse research designs should be used in both countries. Particularly in today‘s aged society, evidence-based research and outcome research are needed for community health nursing in both countries.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.113-116
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• 2008

This work presents numerical optimization for design of staggered arrays of dimples printed on opposite surfaces of a cooling channel with a fast and elitist Non-Dominated Sorting of Genetic Algorithm (NSGA-II) of multi-objective optimization. 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 three non-dimensional geometric design variables composed of dimpled channel height, dimple print diameter, dimple spacing and dimple depth to maximize heat transfer rate compromising with pressure drop. Twenty designs generated by Latin hypercube sampling were evaluated by Reynolds-averaged Navier-Stokes solver and the evaluated objectives were used to construct Pareto optimal front through hybrid multi-objective evolutionary algorithm. The optimum designs were grouped by k-mean clustering technique and some of the clustered points were evaluated by flow analysis. With increase in dimple depth, heat transfer rate increases and at the same time pressure drop also increases, while opposite behavior is obtained for the dimple spacing. The heat transfer performance is related to the vertical motion of the flow and the reattachment length in the dimple.

• Ocean Systems Engineering
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• 제9권2호
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• pp.111-133
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• 2019

Flow through a scaled horizontal axis marine current turbine was numerically simulated after validation and the turbine design was optimized. The computational fluid dynamics (CFD) code Ansys-CFX 16.1 for numerical modeling, an in-house blade element momentum (BEM) code for analytical modeling and an in-house surrogate-based optimization (SBO) code were used to find an optimal turbine design. The blade-pitch angle (${\theta}$) and the number of rotor blades (NR) were taken as design variables. A single objective optimization approach was utilized in the present work. The defined objective function was the turbine's power coefficient ($C_P$). A $3{\times}3$ full-factorial sampling technique was used to define the sample space. This sampling technique gave different turbine designs, which were further evaluated for the objective function by solving the Reynolds-Averaged Navier-Stokes equations (RANS). Finally, the SBO technique with search algorithm produced an optimal design. It is found that the optimal design has improved the objective function by 26.5%. This article presents the solution approach, analysis of the turbine flow field and the predictability of various surrogate based techniques.

• 유통과학연구
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• 제20권5호
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• pp.49-64
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• 2022

Purpose: This research aims to determine the quality of online store designs that make consumers who use online market board applications have the urge to make impulse buying. This research was conducted because impulse buying is the most common buying behavior. Research design, data and methodology: This research used non-probability sampling. The sample size was 195 respondents from the distribution and service industries by applying a purposive sampling technique. The data collection technique employed a questionnaire distributed online according to predetermined criteria: mobile device users who accessed the online market board application and made at least one purchase in the last six months. The data analysis method utilized was structural equation modeling (SEM). Results: The findings revealed that usability, functionality, and sociability factors affected hedonic and utilitarian search. Furthermore, these findings proved that hedonic search affected impulse buying drives. In contrast, the utilitarian search did not affect impulse buying drives. Conclusions: The usability, functionality, and sociability factors supported hedonic and utilitarian searches. Consumer information security increased consumer confidence in an online store because it was considered to protect matters related to their privacy. The hedonic search also increased impulse buying drives. Consumers prefer to use their spare time to search through online market board applications, which provide many attractive promos.

• 한국통계학회:학술대회논문집
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• 한국통계학회 2002년도 춘계 학술발표회 논문집
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• pp.19-24
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• 2002

The two-way balanced one-level rotation design has been discussed (Park, Kim and Choi, 2001), where the two-way balancing is done on interview time in monthly sample and rotation group. We extend it to three-way balanced multi-level design under the most general rotation system. The three-way balancing is accomplished on interview time not only in monthly sample and rotation group but also in recall time. We present the necessary condition and rotation algorithm which guarantee the three-way balancing. We propose multi-level composite estimators (MCE) from this design and derive their variances and mean squared errors (MSE), assuming the correlation from the measurements of the same sample unit and three types of biases in monthly sample.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2632-2635
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• 2003

This paper designs a software signal generator for the new GPS L2 civil signal. The CM/CL code and the message structure of L2CS described in GPS ICD PPIRN-200C-007 are used in designing the signal generator. The output of the GPS signal generator is designed as the sampled IF data with the sampling frequency 5.7MHz and stored in the binary data format. By analyzing both the spectrum characteristics of the output signal and the correlation properties of the CM/CL code, the validation of the designed GPS signal generator is shown. It should be mentioned that the modeling of the GPS satellite constellation and the error sources remains for implementing the software space segment of GPS.

• Journal of Magnetics
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• 제19권1호
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• pp.78-83
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• 2014

This paper proposes an efficient reliability-based optimization method for designing a superconducting magnetic energy system in presence of uncertainty. To evaluate the probability of failure of constraints, samplingbased reliability analysis method is employed, where Monte Carlo simulation is incorporated into dynamic Kriging models. Its main feature is to drastically reduce the numbers of iterative designs and computer simulations during the optimization process without sacrificing the accuracy of reliability analysis. Through comparison with existing methods, the validity of the proposed method is examined with the TEAM Workshop Problem 22.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.405-411
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• 1998

An iterative numerical computational algorithm is presented to design a plate of shell element subjected to membrane and flexural forces. Based on equilibrium consideration, equations for capacities of top and bottom reinforcements in two orthogonal directions have been derived. The amount of reinforcement is determined locally, i. e., for each sampling point, from the equilibrium between applied and internal forces. One case of design is performed for a hyperbolic paraboloid saddle shell (originally used by Lin and Scordelis) to check the design strength against a consistent design load, therefore, to verify the adequacy of design practice for reinforced concrete shells. Based on nonlinear analyses performed, the analytically calculated ultimate load exceeded the design ultimate load from 14-43% for an analysis with relatively low to high tension stiffening, ${\gamma}$ =5~20 cases. For these cases, the design method gives a lower bound on the ultimate load with respect to Lower bound theorem. This shows the adequacy of the current practice at least for this saddle shell case studied. To generalize the conclusion many more designs-analyses are performed with different shell configurations.