• 선박안전
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• 통권33호
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• pp.53-62
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• 2012

펌프는 산업 및 건설현장에 급수, 냉난방 및 산업공정에서 다양하게 사용되고 있으며, 전체 국가 전력의 약 20%를 소비하고 있다. 하지만 에너지 낭비요소에 대한 관리는 거의 이루어지지 않고 있는 실정이다. 따라서 만일 효율이 저하된 상태로 펌프가 운전된다면 그의 에너지 낭비는 대단히 크게 된다. 펌프의 경우 초기 구입비용에 비해 사용하면서 발생하는 전력비용이 대단히 크기 때문에 이러한 낭비를 줄이기 위해서는 펌프의 효율을 정기적으로 측정하여 펌프의 운전 상태를 진단함으로써 펌프의 최적운전상태 및 교환주기 등을 제시할 수 있을 것이다. 본 연구에서는 펌프의 효율측정을 위해 열역학적 방법과 수력학적 방법(전통적인 방법)의 두 가지 방법으로 측정할 수 있는 장비에 대해서 소개하고 실제 펌프의 효율을 계산하여 그 유효성을 확인하였다.

• 대한설비공학회지:설비저널
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• 제10권4호
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• pp.297-303
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• 1981

Optimal design of shell and tube heat exchanger system with the working fluids which may condense outside the tubes has been carried out under specified inlet and outlet conditions. Independent variables such as number of parallel series, tube diameter, distribution pitch, tube side pressure loss, baffle cut and shell side pressure loss as well as dependent variables such as shell diameter, number of tubes, number of serial series and number of baffles were all characterized according to the standard. Exhaustive search method was used to construct a computer program together with the calculation of heat transfer rate by LMTD method. stress analysis of maj or parts was made to examine their dimensions satisfying heat transfer and pressure loss requirements. Cost estimation based on the installation, operation and maintenance was also made, A few representative variables, heat transfer area, shell diameter and pressure loss, were used to express cost function, finally giving the optimal selection of all tentative solutions.

• 대한설비공학회지:설비저널
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• 제12권4호
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• pp.264-274
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• 1983

Two-dimensional jet flows into a couple of confined rectangular enclosures such as an Ondol flue channel and their flow distributions were analyzed by numerical graphics : rectangular space in one enclosure is vacated and the other has 8 rectangular small posts. Both enclosures have a protruded inlet nozzle and on outlet on its center line. Steady state incompressible laminar viscous flow was assumed. The primitive forms of Navier-Stokes equations and continuity equation in a cartesian coordinate system were solved numerically by the Marker and Cell method for Reynolds numbers of 5, 10, 20, 30 and 40. From the numerical graphics it was found that the flow regions in both enclosures were devided into tow parts ; one part was the jet flow localized in a narrow center region of the enclosure and the other part was the very slow recirculating flow occupying the rest of the flow region in the enclosures. However there were a little differences in the shapes of jet flow in both enclosures for Reynolds numbers of 5 and 10 and also in the shapes of recirculating flows in both enclosures for all Reynolds number. Also it was found that waving flow appeared right before the outlet at Reynolds number of 20 and more.

• Journal of Nutrition and Health
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• 제38권2호
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• pp.161-172
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• 2005

Children regard newspapers and magazines as the important source of information. Because informations about diet in the newspaper and magazines are regarded as good, it is necessary to find out whether informations provided to children are correct. Thus, this study shows the present situation of informations on diet by monitoring 3 newspapers (Kids. Chosun, Kids. Donga, Kids. Hankook) and 2 magazines (Earinee - Dongsan, Sae-But) for children. This study focused on the quantitative and the qualitative analysis for articles and advertisements. For the quantity, rate and number were calculated. For the quality, the accuracy was analyzed. Result of this study were as follow; Analyzed the number of articles and advertisements on diet, there are 2 times more number of advertisements (339 cases) than that of articles (180 cases) in the newspaper. There are slightly more number of advertisements (24 cases) than that of articles (18 cases) in the magazine. Most of advertisements are about processed foods and children' favorite foods. Especially, the advertisement of processed foods are ranked first by the quantity with 245 cases (75%) in the newspaper. In the magazine, 10 cases (42%) are about processed foods. About source of advertisements on diet informations in the newspaper, there are 300 cases (86.7%) without evidence based data and 34 cases (9.8%) of interview with entertainers, from the total 346 cases. In the magazine, there are high rate of cases without evidence based data and interview with entertainers. For the evaluation of the information about diet in the newspaper, there are 148 cases (19.7%) with no clear guidance and position, some cases with advertisements for specific products and etc. Discordance between subjects and contents, and emphasis of specified field or some parts are found from the total 750 cases. About the accuracy of contents, from the total 180 cases in the newspaper, 99 cases (55%) are inappropriate and 19 cases (10.6%) are appropriate. In magazines from the total 18 cases, 7 cases (38.9%) are inappropriate and 11 cases (61.1 %) are appropriate. With these results, we can conclude that informations about diet in newspapers and magazine for children needs improvement. Therefore, for newspapers and magazines contents should be reported scienifically by inspecting contents and by taking professional advice, in order to spread the accurate information about diet. Also, there are need to manage the systematic monitoring, for children. (Korean J Nutrition 38(2): 161～172, 2005)

• 복식
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• 제51권8호
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• pp.93-110
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• 2001

The present study attempted to compare the behavioral patterns and attitudes of American and Korean female students toward apparel ads in magazines in relation to their physical self-concept. The study used a self-administered questionnaire. The sample consisted of 730 female students majoring in the fields related to clothing and textiles : 310 American students at six colleges and universities located in the west, northeast and southwest parts of the U.S., and 412 Korean students at four Seoul-based universities. Likert scales were used for most measures with 1=never or very unimportant and 5 =always or very important. Physical self-concept was measured on the basis of W. S. Jung's Standardized Self-concept Test and Tennessee Self-concept Scale. Surreys were back translated for validity. Percentage, t-test, Contingency Tables and Chi-square were used for the analysis of the data. Results are as follows : (1) Korean students read more magazines than U.S. students, however, Vogue was the most popular for both groups. (2) Those with a high sense of Physical self-concept read more magazines. for both countries. (3) American students'attitudes toward apparel ads in magazines were similar, regardless of whether their sense of physical self-concept was high or low. For Koreans, those with higher sense of physical self-concept showed greater interest in magazine ads, consulted magazines for fashion trends, found ads more useful, and more often expressed satisfaction with the ads, than the lower self-concept group. (4) Korean students cited a lack of information in ads while American students felt body types of models were unrealistic. Both Koreans and Americans in the higher self-concept group expressed a greater level of dissatisfaction with apparel ads in magazines. (5) Advertisers should attempt to again a deeper understanding of the socio-psychological characteristics of their readership as self-concept appears to be related to several magazine readership attitudes and behaviors. Magazines targeting Americans might consider the importance of coordination and merchandising. Apparel ads targeting Korean should consider the importance of company ads.

• 화훼연구
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• 제16권1호
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• pp.7-11
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• 2008

본 연구는 화훼장식에서 대나무의 다양한 활용을 위해 2001년부터 2006년까지 월간잡지 플레르(Fleur)와 국제꽃장식대회의 대나무 작품 108개를 토대로 조사하였다. 대나무의 사용부위에 따른 사용빈도와 작업형태, 조형형태, 그리고 작품 안에서 대나무의 배열 기법을 분석하였다. 대나무의 사용부위는 줄기가 전체 작품에서 90%를 차지하였다. 줄기가 사용된 97작품 중에서 국제 꽃 장식 대회는 매년 4월에 열리는 특성으로 대회에 나온 20작품을 제외한 월간 잡지 '플레르(Fleur)'의 77작품을 월별로 분석한 결과, 월별 대나무가 쓰인 작품의 수는 새해의 시작인 1~2월과 한여름인 7~8월이 가장 많았다. 줄기를 사용한 97작품에서 줄기가 사용된 형태를 조사 분석한 결과, 가공하지 않고 자연그대로 사용한 작품이 63%로 나타났다. 작품 속에서 대나무의 배열 기법은 수직 병렬형이 48%로 가장 많았다. 기타는 수직, 수평, 사선에 포함되지 않는 원형의 작품들을 분류한 것이다. 대나무가 쓰인 작품의 작업유형은 테이블장식을 포함한 50% 이상이 공간장식의 형태를 나타내었다. 대나무가 소재로 쓰인 작품의 조형 형태는 장식적 형태가 64%, 그래픽적 형태가 30%, 선형적 형태가 4%로 나타났다.

• 기술사
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• 제14권2호
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• pp.52-61
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• 1981

In Korea Small-medium Companies Constitutes 96.5% of all of the mining and manufacturing industries, about 35.7% of the total production of value added business, an average of 35% of the actual export of industrial goods and 47.6% of employment since present at the end of 1979. Now then Small-medium Industry Companies organization style constitutes 78.6% of a form of private company and 81.2% of the total on an small scale under 50 persons inregular employee. Specially, the trouble of business management of the mining and manufacturing Companies in Korea are constituted average 28.3% of production management ill the worst trouble of business management from 1973 to 1979 and small-medium industry Companies are the same of about more than 30% of production management in the trouble of business management. In this cases, the status of production management is effected by small-medium industry companies are the style of non-system and non-organization, but then 13parts in production management operations have the many trouble problems. In this circumstances a change for the better of production management operations in small medium industry companies are suggested the application effects and achievement points of production management, it is suggested a kind of variety and a small quantity, production management system of small-medium industry Company. And then Industrial Engineering technics is applied systematic route and the company grow more than better its physical condition for the improve productivity applied system approach for production management. There for the chapter 4-5 of this paper treats of a rational production management system approach, it make a emphatic major point of high level of economic growth of small medium Industry enterprise.

• 항공우주산업기술동향
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• 제8권2호
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• pp.124-135
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• 2010

2009년 4월 27일 일본과 미국은 항공기 및 부품의 감항성인증을 상호수락하기 위한 항공안전협정(BASA) 및 감항성이행절차(IPA)를 체결하였다. 항공안전협정이 해당 민간항공당국이 수행해야 하는 법적 책임을 경감시키지는 않는다. 다만, 역량있는 상대국가의 감항당국이 해당 민간항공당국을 대신하여 자국의 항공기 인증제도에 필적할 만한 방법으로 수행한 인증기능을 인정하는 방법을 통하여, 해당 민간항공당국은 적합성판정을 함에 있어서 대체방법으로 활용하는 것이다. 이를 통해 항공안전협정은 안전을 저해하지 않으면서 여러 국가의 인증에 소요되는 비용과 시간을 경감시키면서 교역을 촉진하는 데 기여하고 있는 것이다. 본 논문에서는 가장 최근에 미국과 BASA를 체결한 일본의 항공기 인증제도 및 항공안전협정 체결 현황에 대하여 제시한다.

• 한국농공학회지
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• 제18권1호
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• pp.4021-4037
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• 1976

This paper describes the actual experiments of the error propagation and studies of analytical photogrammetry using the simulation method in which we can find the causes of the errors. These studies and the results give the valuable data which are very effective for systematically controlling the errors in aerial triangulation. The main contents in my paper are as follows: 1. Dose the scale errors in the successive models in the form of normal distribution appear when the observation errors propagate in the form of normal distribution\ulcorner 2. In what form does this scale error propagation in the actual model appear\ulcorner 3. When the causes of the scale error propagation are found, is the evaluation standard determined normally\ulcorner 4. What degree of influence is there form the constant errors\ulcorner I have done several experiments using the simulation method technique to solve the complicated error propgation of aerial triangulation which is the effective means to research the relations between cause and effect. In this paper, the studies have concentrated on the following points of simulation experiments. (1) The first part descries how we can produce the soft program of the simulation experiment. (2) The second part is the method propagating the errors in the simulation models and the kinds of errors. (3) The final part is the most important; that is the analyzing and evaluation of control during actual work. From the above-mentioned points, it is said that these studies are a very important development in the field of controlling and managing aerial photogrammetry and especially in the case of error propagation, we can clearly find the causes of the errors and steps and parts of errors generated when we use these techniques.

• 한국농공학회지
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• 제39권4호
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• pp.90-97
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• 1997

Field inspections and laboratory tests for 31 agricultural reservoirs in Kyungki province were performed to provide basic data for maintenance and rehabilitation of agricultural reservoirs and to evaluate structural degradation of agricultural reservoirs Results of the study are as follows : 1) From survey's results of embankments, signs of settlement and lateral movement are appeared in 17 reservoirs. Crest settlement of 20~80cm, downstream settlement of 10~90cm, and 20~160cm lateral movement of embankments are detected from settlement and movement analysis of 17 reservoirs. Crest and downstream settlements and lateral movement are greatly occurred in 20 ~ 40 years after embankment construction. 2) About 39% of total reservoirs shows seepage problems occurred in the lower part of berm and retaining wall located between embankment and spillway. Probability of seepage problems is higher at retaining wall than others. 3) Concrete strength estimated by Schmidt hammer in structures of reservoirs is a range of 100~l50kgf/$cm^2$ and average deviation of concrete strength is about l0kgf/$cm^2$. Strength difference$({\delta}S)$ between compressive strength estimated by Schmidt hammer and uniaxial compressive strength of concrete core is about $\pm$100kgf/$cm^2$. This difference is due to absence or presence of reinforced bar in concrete core, variable length of concrete core and limitation of Schmidt hammer. 4) About 68% of total reservoirs shows leaching, 58% alkali-aggregate reaction and 71 % abrasion/frost. Leaching, alkali-aggregate reaction and abrasion/frost occurred in most reservoirs when passed 10 years after construction of structure parts.