• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.180-184
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• 1998

Recently the performance of CO2 arc welding machine has been advanced significantly through the adoption of inverter circuit topology which made it possible to control the waveform of welding current and thus to suppress the spatter generation. However, the optimum waveform is still uncertain. As a first step for figuring out the promising waveforms, this study was performed to set-up the experimental system for studying the effect of waveform variables. The overal system is controlled digital controller using single chip microprocessor of 80C196KC. As a result of performance test of this system, it was demonstrated all of the waveform variables could be set individually and the generated spatter is reduced compare to conventional inverter arc welding machine.

• 아시안잔디학회지
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• 제7권1호
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• pp.13-18
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• 1993

Much attention has been given recently to solve the environmental contamination in golf courses Changing to culture practice rather than chemical practice that depends on pesticides and fertilizers is a hot issue in golf courses or grasslands. Organic soil conditioners improve soil-plant envirormental conditions rich in physical properties. In this study, measuring systems to evaluate soil conditioning effects were set up for on-site purpose. After establishing the methodology for evaluating soil conditioner effects, 2 kinds of organic conditioners were rested for examination. The systems for the methodology included a set of simulating equipment for field capacity, an impact type soil column compactor, and an infiltration-percolation system. Test results using the systems showed bulk density and infiltration rate of mixed soil were decreased at highter rates of conditioner, but total porocities were increased. Increased porocities were most capillary pore space which has a positive effect on soil water potential. The systems and methodology in this study seem to have an efficiency to measure the effects of soil conditioner on site purpose.

• 무역상무연구
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• 제40권
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• pp.33-63
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• 2008

This study introduces the adoption of the logistics industry by the Korean government as a threshold of overcoming economic difficulties. The core contents of the National Logistics Plans (2001-2020) which contain the basic principles of the logistics policies of the Korean government and its aim to be an 'Excellent Nation of Logistics' is introduced. The economic effect of the logistics policies implemented between 2001 and 2005, (the period of the first Medium-term Logistics Plan according to the National Logistics Plans (2001-2020) set up by the Korean government at the end of 2000) is estimated through input-output analysis. The input-output analysis result is as follows: the total output effect is 8,856 billion won of which indirect output effect is 3,982.9 billion won; indirect output effect comes mainly from real estate and business services, non-metal products, metal products, electrical and electronics products, finance and insurance, wholesale and retail, petroleum and coal; the total amount of value-added effect is 3,376 billion won and total import effect is 726 billion won. Employment effect including self-employed and unpaid family supporters with paid laborers is 79,203.7 people of which paid laborers comprise 67,547.7 people.

• 정보저장시스템학회논문집
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• 제8권2호
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• pp.39-43
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• 2012

In spite of many advantages, the practical application of the thin film solar cell is restricted due to its low efficiency compared with the bulk type solar cells. This study intends to adopt the surface plasmon effect using nano particles to solve the low efficiency problem in thin film solar cells. By inserting Ag nano-particles in the absorbing layer of a thin film solar cell, the poynting vector value of the absorbing layer is increased due to the strong energy field. Increasing the value may give thin film solar cells chance to absorb more energy from the incident beam so that the efficiency of the thin film solar cell can be improved. In this work, we have designed the optimal shape of Ag nano-particle in the absorbing laser of a basic type thin film solar cell using the finite element analysis commercial package COMSOL. Design parameters are set to the particle diameter and the distance between each Ag nano-particle and by changing those parameters using the full factorial design variable set-up, we can determine optimal design of Ag nano-particles for maximizing the poynting vector value in the absorbing layer.

• 한국약용작물학회지
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• 제20권5호
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• pp.315-319
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• 2012

This study was conducted to select plant growth regulators effective at ginseng berry set inhibition to help root growth in Korean ginseng (Panax ginseng C. A. Meyer). PGRs (ethephon, gibberellic acid, maleic hydrazide, coumarin) were applied to field grown 5-year-old Korean ginseng between one and two times, before and during bloom in 2009, 2010. The number of treatment was more effective in ginseng berry set inhibition when used two times compared with one time in GA 1,000 ppm, MH (5,000, 10,000 ppm), coumarin (5,000, 10,000 ppm) treatment. According to treatment period of plant growth regulator, ginseng berry set inhibition rate from 20days before flowering date to 5days after blooming was the highest in MH 5000 ppm showing 99.9% and the lowest in GA 100 ppm showing 32.8%. The spray treatments of Ethephon (50, 150 ppm) and MH (5,000, 10,000 ppm) from 20 days before the flowering bloom up to 5 days before, and coumarin (5,000, 10,000 ppm) from 20 days to 6 days and before blooming that induced the inhibitory effect more than 90% after 12 weeks. Considering ginseng berry set inhibition characteristics and treatment period ethephon and coumarin was important about applied period but, MH treatment appeared to effective ginseng berry set inhibition regardless of treatment period.

• 기록학연구
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• 제18호
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• pp.37-89
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• 2008

국회의 기록관리체제는 1999년에 기록물관리법이 제정되면서 대폭 개편되었다. 원래 국회는 총무과, 의안과, 속기과 등에서 영구보존기록물을 관리하였으나 기록물관리법이 제정되면서 국회기록물의 보존체제가 크게 개편되었다. 1948년 국회가 설립된 이래로 최초로 전문적인 기록물관리부서로서 국회기록보존소가 설치되었고, "국회기록물관리규칙"의 제정을 계기로 의안과, 속기과 등의 기록물 보존권한이 부정되었다. 이에 따라 국회기록보존소는 종전 국회사무처와 국회도서관의 각 부서에 분산되어 있던 기록물의 수집 보존 등의 업무를 모두 관할하게 되어 국회의 종합적인 기록물 수집 보존 및 편찬 부서로서의 위상을 확보하였다. 기록물관리법의 제정과 국회기록물관리체제의 개편은 한국국가기록관리체제가 헌법기관에서 어떻게 구현되는지를 잘 보여주는 사례이다. 기록물관리법의 제정 이전에는 "정부공문서규정" 등이 행정부의 기록관리에 관한 법령이었으나 이 같은 규정을 국회에까지 적용할 의무는 없었다. 그러나 1999년에 '법률'의 형식으로 기록물관리법이 제정되면서 국회는 기록물관리법의 시행을 위한 후속조치가 필요하게 되었다. 국회는 이 같은 후속조치의 일환으로서 국회기록보존소 설치와 "국회기록물관리규칙" 등의 개선작업을 추진하였다. 이 연구에서는 기록물관리법이 국회에 어떠한 영향을 미쳤고 국회는 기록물관리법의 국회 시행에 어떻게 대응하였으며 국회기록물 관리실태가 어떻게 개편되었는지를 중심으로 분석하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.802-805
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• 2007

The exhaust system, including a muffler, is one of the major sources to generate the radiated noise of construction equipment. The muffler is generally known that it reduces the exhaust noise level, but it sometimes increases the noise level because of the flow effect inside a muffler. So, it is required to consider the flow effect inside a muffler to reduce the exhaust noise level of construction equipment. In this paper, an experimental method to consider a quantitative flow effect inside a muffler was set up through a series of tests. Finally, the experimental result was verified through the flow noise analysis using CFD analysis result. These results make it possible to understand the dynamic characteristics of the flow noise and to design the low noise muffler for the construction equipment.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 추계종합학술대회
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• pp.669-672
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• 2000

This paper presents the methodology which analyze the effect of harmonics in power system. Considering the effect of less-harmonics, economic life and system loss, we have made the comprehensive countermeasure. According to the results of studying harmonics diagnosis and countermeasure, the following problems are pinpointed: protection of power system double investment space of the field. Therefore, in the initial stage, the countermeasure of harmonics trouble are set up. h a results, the following work has been done: $\circled1$ Generation source of harmonics and it's effect into en power system $\circled2$ Review of law related to harmonics, $\circled3$ Countermeasures to reduce the harmonics

• 한국조리학회지
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• 제14권4호
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• pp.217-231
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• 2008

The purpose of this study is to examine how the perceived physical environments of hotel kitchens influence cooking employees' internal responses. According to the analysis results of this study, except Hypothesis 2 which was rejected in this study, all the hypotheses were partially accepted. These results support the research hypotheses of this study that comfort, spatiality, and convenience as physical environments will have significant effects on emotional response and cognitive response. Also, equipment use as convenience had statistically significant effects on both emotional response and cognitive response whereas working environment as comfort and kitchen circulation and working space as spatiality had no effect. Therefore, kitchen environment should be set up in the direction of guaranteeing kitchen convenience to the maximum, and the further researches on the constituent factors which have no effect on emotional response and cognitive response should be proceeded continuously.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.376-379
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• 2010

Bubble rising phenomenon is widely founded in many industrial applications such as a stream generator in power plant. Many experimental and numerical researches have been already performed to predict dynamic behavior of the bubble rising process. Recently numerical approaches are getting popular since it can offer much detailed information which is almost impossible to obtain from the experiments. Rising bubble could penetrate through the top free surface which makes the problem much more complicate in addition to the phase changing effect even with latest numerical techniques. In this paper, the top free surface effect on rising bubble has been investigated. The gas-liquid interface was explicitly tracked using high-order Level Contour Reconstruction Method(LCRM) which is a hybridization of Front-Tracking and Level-Set method. Break-up behavior of rising bubble at free surface showed different characteristics with initial diameter of bubble.