• Steel and Composite Structures
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• 제2권3호
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• pp.195-208
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• 2002

Elasticity solutions to the boundary-value problems of dynamic response under transverse asymmetric load of cross-ply shallow cylindrical panels are presented. The shell panel is simply supported along all four sides and has finite length. The highly coupled partial differential equations are reduced to ordinary differential equations with constant coefficients by means of trigonometric function expansion in the circumferential and axial directions. The resulting ordinary differential equations are solved by Galerkin finite element method. Numerical examples are presented for two (0/90 deg.) and three (0/90/0 deg.) laminations under dynamic loading.

• 소성∙가공
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• 제29권2호
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• pp.113-117
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• 2020

Various parameters are involved in the frictional behavior of steel sheet during stamping. We performed various tests in order to investigate the influence of tool surface texture directionality upon the resulting friction in sheet forming processes. Four different tools were manufactured which gave us a range of roughness for both parallel and transverse texture directions. Each of the tools was examined in flat type friction tests under identical test conditions. The tool with the transverse surface texture produces significantly lower levels of friction than the tool with parallel texture direction. Considering the lubrication mechanism associated with transverse texture, one can imagine the lubricant being constantly supplied from the reservoir of the micro valley to the point of contact and hence producing the lower levels of friction seen.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.165-168
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• 1998

This paper describes the characteristics of CT-2 radio wave propagation at 900MHz range. Typical cell coverage of CT-2 based on picocellular design provides a 200m radius. The five sites of urban regions of Kwang Ju city were chosen to characterize propagation in various environments. On the basis of cell coverage data measured with field strength meter, average 75% of telepoint service was retained and it was lack 25% of overall gain. In some sites telepoint service was limited to two of four directions around a station. If specially designed collinear antenna with specific directivities are used in these shadow area, improved results will be acquired.

• 복식문화연구
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• 제16권4호
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• pp.595-608
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• 2008

Although Korean apparel companies have transformed dramatically from contractors to sourcing companies thanks to the rapid growth of local market, relatively little work has been done identifying the determinants and the patterns of global sourcing activities of Korean companies. The purpose of this study was to outline a conceptual model that may be used to organize and guide global sourcing activities of Korean apparel manufacturers and retailers. The conceptual model identified four important factors, cost factor, strategic non-cost factor, firm's internal factor, and global factor, which affect global sourcing strategies and help predict how companies conduct various sourcing activities. The model also identified two sourcing patterns, outsourcing and intra-firm sourcing. In developing the model, literature review on how manufacturers and retailers in diverse areas including global apparel sourcing was conducted. Managerial implications and directions far future study were offered as well.

• 한국컴퓨터정보학회논문지
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• 제23권7호
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• pp.121-129
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• 2018

Since 2005, POSCO has been conducting continuous innovation activities using its own innovation methodology, QSS + (Quick Six Sigma Plus). Recently, the effectiveness of QSS + has been decreased owing to the different needs and purposes for each group. The purpose of this study is to compare the weights of the QSS + factors using AHP analysis. QSS + factors consist of two levels. The high level consists of 7 items : 'Master Plan, Waste Zero Activity, Daily Improvement Activity, Talent Development, Project Activity, Initiative/Encouragement activity'. The low level consists of 3 items '5S, My Machine, My M&S' for Daily Improvement Activity. As a result, we found that there was a difference between the weights of the four groups. We suggest the effective QSS + directions to improve the quality of POSCO.

• 산업기술연구
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• 제24권B호
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• pp.29-36
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• 2004

The wind and wind-induced dynamic wind pressures fluctuate irregularly according to time and space. In this study, the proper orthogonal decomposition(POD) technique is applied to wind pressures acting on a tall tower model, and the following results are found: the along-wind and across-wind forces can be reconstructed by only four dominant POD modes, and the reconstructed errors are 4.71% and 22%, respectively for across-wind and along-wind directions. The physical meanings for dominant modes are also presented in the paper. The POD analysis can compress complex wind pressure data only by a few dominant modes and interpret spatio-temporal characteristics of wind pressure by novel way while existing statistical methods do not have such benefits.

• 품질경영학회지
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• 제42권4호
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• pp.529-542
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• 2014

Purpose: Eight goals in Millennium Development Goals (MDGs) and temporary 12 goals in Sustainable Development Goals (SDGs) as the UN projects are investigated in detail. Methods: Investigation of statistics for life qualities, diseases, and life costs. Results: By examining the shortcomings of MDGs, temporary goals of SDGs are suggested. In addition, four countermeasures are recommended for further consideration. Conclusion: It is necessary to cooperate MDGs with more interest and prepare the new age for SDGs by compensating the shortcomings of MDGs. Finally, this paper suggests creative directions for SDGs which will be supposed to start in 2016.

• 한국초등과학교육학회지:초등과학교육
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• 제26권2호
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• pp.201-208
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• 2007

The purpose of this study was to analyze the structure and type of prospective elementary school teachers' scientific hypotheses generated on zoological tasks. The subjects were 18 prospective elementary school teachers. Four zoological hypothesis generation tasks were developed and administered to the subjects. After being presented with the zoological situations of the tasks, the subjects were asked to generate causal questions and scientific hypotheses. The scientific hypotheses were analyzed by the inductive approach. The results of this study showed that the hypotheses contained explicans and explicanda. The explicans were divided into two parts: 'what' and 'how'. In some cases, additional explanations were attached to the 'what' section. In addition, the hypotheses were classified into 9 types. The number of explicanda, the pattern of explicans, and the number of explicans were used as criteria for classification purposes. This study also discussed the implications of these findings for future directions in teaching and teaming in science education.

• 한국공간구조학회논문집
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• 제15권3호
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• pp.61-68
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• 2015

A study on BRP(Building Rapid Printing) technology is in an initial stage although general 3d printers are being developed in a great speed and with fruitful outputs. Even some laboratories in advanced countries have difficulties in their research due to many technological restrictions and have not produced a practical output yet. This paper proposed distinct directions in which the research of this aera should be developed and this manifested four areas - printing speed, reinforcing tech, material tech and nozzle tech and those areas were proposed with concrete development alternatives and objects.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.1147-1150
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• 2003

When a braun tube becomes wider, one of the major problems to be experienced is the non-uniform coating along the four diagonal directions on its surface. This non-uniformity in the coating thickness has a deep relation with the fluid flow on the surface of a braun tube. In order to control the fluid flow properly, we install the plate to block fluid flow at the corner of a braun tube. In the present study, we investigate the effects of the geometry of plate to control the fluid flow and coating uniformity and determine the optimal shape of plate to improve the quality of coating uniformity.