• Journal of Korean Society of Coastal and Ocean Engineers
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• v.7 no.2
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• pp.156-162
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• 1995

A numerical method for a 2-D oil boom model considering the flexibility of skirt has been developed The neater is assumed rigid and the skirt is tensioned membrane having a point mass at its end The fluid motion is potential. The kinematic condition which demands the continuity of the displacement is imposed at the joint between the floater and the skirt. The dynamic condition for the point mass is imposed at the bottom end of the skirt. The numerical method is based on the Green's function method in the frame of linear potential theory. It finds it's solution simultaneously from the total system of three equations, integral equation, the equation of motion of the floater and the equilibrium equation of the deformation of the skirt. Integral equation is derived by applying the Green's theorem to radiation potential and Green's function. Proper descretization of those three equations leads to the system of a linear algebraic equation. Due to the flexibility of skirt the motion of floater can be diminished in some range of wave frequency and furthermore the mechanism of resonance of the oil boom can be changed. The motion responses of various oil booms have been compared varying the length of the skirt and the point mass. The numerical method has been validated indirectly from the good correspondence between the motion responses of the flexible skirt model and the rigid skirt model in low frequency limit.

• Korea journal of population studies
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• v.8 no.1
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• pp.47-65
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• 1985

Three stages of population growth during last forty years affected differently to the labor force and employment in Korea. The first impact of rapid population growth on the labor force occured after the end of World War II. Sudden growth of population due to repartriation and refugees directly increased the labor force. Deteriorating labor market conditions were caused not only by the explosive labor supply but also by the shortage of employment opportunities due to a lack of productive facilities. This severe excess supply of labor continued until the early 196Os. Population growth in the second stage which caused by high fertility during the post Korean War baby boom period induced an eventual increase in the labor supply with time lag of more than fifteen years. Younger persons born during baby boom period were flooded the labor market. Fortunately, job opportunities were expanded more rapidly than the labor force supply because high rates of economic growth and speedy industrialization were continued until the later half of 1970s. Unemployment, therefore, decreased dramatically during this period. The effect of third stage which is characterized as mitigated population growth due to birth control has appeared in the labor market since late 1970s. The growth rate of labor force has been going down and the proportion of younger workers was also been decreasing. From the early 1980s, furthermore, partial disharmony between supply of and demand for the younger workers is closing up. Less educated younger workers who works at low wage are lacking while more educated youngers who want to work at high wage are being excess, because a lot of younger prefer higher education rather than productive job. It is expected that the structural inharmony will be diversified in the future in Korea. The labor force will be changed to middleaged, highly educated and womenized till year 2000, and, after then, to old-aged. On the demand side, industries and jobs will transferred to be labor-saving and soft. These structural changes of labor supply and demand will not matching in time. Aggregate supply of labor force will be steadily increasing more rapidly than aggregate demand for labor until year 2000, and this trend will continue to the first one or two decades of the 2lth century because the persons born dufing the baby boom pariod are being eligible couples in recent. Therefore, conclusion is that appropriate manpower development policy as well as sustained birth control policy is necessary for harmonizing the structural unbalance and the disequilibrium between aggregate labor supply and demand in the future.

• The Journal of Korean Medical History
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• v.15 no.2
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• pp.101-108
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• 2002

"DongYangEuiYak" is a magazine that was published three times to reconstruct Korean medicine. Publishing the magazine was leaded by excutives of the East and West Medicine Research Society, especially Kim younghun and Cho hunyoung. The magazine contains reconstruction of Korean medicine, medical history, pulse, herb, Sasang medicine and etc, in depth. Editorial department of "DongYangEuiYak" tried to boom Korean medicine and reeducate the people working in Korean medicine field by answering reader's questions and medical counselling articles and articles in correspondence course form. Studing courses and founding herb town after the publishment of "DongYangEuiYak", reflects well the culminated atmosphere of Korean medicine.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.11a
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• pp.201-204
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• 2000

It seems that the \"fuzzy boom\" which began with its applications has calmed down and fallen into decay at least in Korea. But many foreign researchers say the research related to fuzzy theory has been only running its right course. In this paper, we discuss the trend and direction of reaserch related to fuzzy theory. The search trend is obtained through the analysis of the papers of the latest 10years papers in the journals of three societies: KFIS, SOFT and IFSA.

• Journal of the KSME
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• v.20 no.1
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• pp.40-51
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• 1980

근래 음향학(acoustics)이 기계공학과의 일전정과목으로 등장하여 일시 미국에서 과학공학종의 취직난이 있었을 때에도 음향학전공생들은 직장을 얻게되었다. 연이나 음향학과 유체역학의 상 호관념은 그 기초적연구에서나 응용에서는 특수한 항공공학계에서 관심을 둔 분유소음(jet noise) (Blumenthal, Russell과 Streckenabach(1975)과 Banerian(1978) 참조) Sonic boom(Carlson과 Maglieri(1972) 참조) 또 미해군에서 주목한 흐름의 소음 (flow noise) 같은 부분이외에는 별로 큰 진전을 보지못하고 있다. 그러므로 음향하종에게나 유체역학전문가에게는 많은 과제가 남 겨있다. 음향은 유역에 변화를 일으키고 흐름의 특성을 변시키므로 이 문제에 대하여 유체역학 견지로써 알아보고져 한다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.264-270
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• 2003

우리나라의 방제작업은 주로 소형 동력분무기를 이용한 것으로서 총포형 노즐을 사용한다. 그러나 이 방법은 농약의 살포량 조절이 어렵고 불균일한 살포로 방제효과가 높지 못하여 개선이 요구된다. 또한 필요량보다 많이 뿌려 흘러내릴 정도로 살포하므로 환경에 악영향을 미칠 가능성이 높고, 농산물 안정성에도 불신을 초래하고 있다. 붐방제기는 이런 요구에 부응하는 대체 방제기계이지만, 우리나라에서는 수도작용을 중심으로 보급되었다. (중략)

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.83-89
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• 2003

붐방제기는 분무관에 일정한 간격으로 노즐이 설치되어 있으며 목표물 바로 위에서 농약을 직접 살포할 수 있다. 따라서 비산의 위험성이 적고 작업폭이 넓기 때문에 포장능률도 높은 장점이 있다. 또한 방제작업에 영향을 미치는 방제속도, 살포폭, 노즐 배출량, 노즐 압력 등을 최적으로 유지할 수 있는 자동제어 시스템을 채택할 수 있어 최적량의 농약을 균일하고 유효하게 살포할 수 있다. (중략)

• Journal of Agricultural Extension & Community Development
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• v.11 no.1
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• pp.139-159
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• 2004

Since 1990s, the countrysides in Seoul Metropolitan Area have been exposed to the unprecedented forces like developing telecommunication technology, the boom of exurban housing, increasing concern about food quality. While these new forces are restructuring the social and spatial pattern of countryside, a legal regulation can be assumed as exerting an overarching moulding power. This paper shows how the legal regulation works in the restructuring rurality.

• Proceedings of the KIEE Conference
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• 2003.07e
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• pp.127-131
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• 2003

We have investigated about kinds of the equipment according to use. They have many kinds of equipments, namely conductive cloths, insulated gloves, conductive shoes, insulated sticks, swivel boom, fittings and insulator cradles etc. We have suggested about use of equipments, basic functions and shapes.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.6-8
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• 2004

A big boom in nanocomposites research has landed also in Japan. As a virtual 'center of excellence' in composites technology there, ACE TeC of ISTA/JAXA has led pioneering portions of nanocomposites research particularly in mechanical properties oriented applications. An overview of research activities based on nano-technologies in ACE TeC/JAXA will be given first and some remarkable results will be introduced briefly.