• 한국인터넷방송통신학회논문지
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• 제22권1호
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• pp.35-43
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• 2022

본 논문에서는 10W급 MMIC를 결합하여 20W급으로 상향시킨 단위 전력 증폭기를 8-way 공간결합기와 결합하여 100W급 SSPA를 제작하는 연구를 진행하였다. SSPA는 TWTA에 비해 상대적으로 낮은 단일 소자의 출력으로 높은 출력을 충족하기 위해 저손실, 고효율의 결합 기술을 필요로 한다. 본 논문에서 설계 및 제작된 SSPA는 20dB 이상의 반사 손실과 94% 이상의 우수한 결합효율을 갖는 8-way 공간결합기에 20W급 고출력증폭모듈 8대를 장착하여 100W급 SSPA로 제작되었다. -10dBm 인가시 20kHz 20%에서 112.2~169.8W, 400kHz 40%에서 125.9~173.8W, 800kHz 40%에서 117.5~162.2W로 나타나 PRF 3가지 조건에서 모두 이득 60dB 이상과 100W 이상의 성능을 보였다.

• International Journal of Contents
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• 제7권4호
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• pp.77-83
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• 2011

This paper is an inquiry into the human sensibility on view from high-rise housing in a viewpoint of architectural environment design that pay attention to multi-family high-rise housing which is becomes a trend in recent years. And this paper is the fundamental approach for applying this result to later architectural environmental plan of multi-family high-rise housing. In this paper, we used repertory grid method as a cognitive psychological way of analysis and eye mark recorder measurement experiments as a physiological way of examination. In the conclusions, examined human sensibilities on views-focused on the analysis result of eye mark recorder measurement experiments through repertory grid method that are carried on the main subject-and described problems after this and possibilities in the same time.

• 한국주거학회논문집
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• 제6권1호
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• pp.19-29
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• 1995

This study is to analyze the effect of neighborhood commercial facilities on the homeproduction activities and the family expenditure(or household work time). For this purpose. data are collected by using questionnaires distributed to 522 housewives in Seoul. The results shows that in the highly goods-intensive environment. the way of homeproduction is goods-intensive. Market dependence of the family is affected by homeproduction predisposition. income. and husband's job. Household work dependence of the .family is affected by neighborhood facility environment. family type. income. and house value. Low home production supportability is apparent in the high family income. full-time housewives and low job status of housewife. On the other hand. high homeproduction supportability is apparent in the moderate income and high job status of housewife. As a result. housewives have much time and money resourses are not well supported by the neighborhood facility environment.

• 한국산업융합학회 논문집
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• 제9권1호
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• pp.73-78
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• 2006

Constructing a long, linear structure such as a high-way may cause the break-up of the natural ecology by cutting off the trails of animals. We could observe 12 kinds of mammals, 49 kinds of birds and 10 kinds of amphibia and reptilia at the research area. With this research, we were so sure of the necessity of building ecological corridors to prevent the ecological break-up of wild animals that we studied the building and maintaining of 3 types of ecological corridors; tunnel types, over-bridge type and line type.

• 한국대기환경학회지
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• 제11권2호
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• pp.153-162
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• 1995

As exhaust emission standards for new passenger cars amended in 1987 have become more stringent, vehicle manufacturers have employed three-way catalyst in order to meet these requirements. The purpose of this study was to gather informations on new emission control systems in customer use for in-use vehicles from the 1987 through 1992 model years were capable of achieving low exhaust emission levels although high levels do occur due to defects, deterioration or maladjustments with the emission control equipment. The vehicles with closed loop electronic control fuel injection system emitted low exhaust emission, but the carburetor control system equipped vehicles emitted high exhaust emissions and the high mileage vehicles exhibited higher average emissions than low mileage vehicles. It was also found that the useful life of 80, 000km is very important to maintain the low emission levels within customer service period.

• 한국자동차공학회논문집
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• 제3권2호
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• pp.122-129
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• 1995

This is an experimental study on the chassis dynamometer and high way road testing during a severe winter and summer season. Results obtained to compare with the ultrasonic fuel feeding system and conventional fuel system in diesel automobile engine. The results were as followers in case of the ultrasonic fuel feeding system. 1. In chassis dynamometer testing during given vehicle speeds, output were increased from 4.6 to 11.43%, brake specific fuel consumption were increased from 6 to 19%, smoke were decreased from 16.7 to 50%. 2. The running fuel consumption ratio in high way road test were decreased by 15.3% at a severe summer and 20.2% at a severe winter.

• 대한정형도수물리치료학회지
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• 제29권2호
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• pp.39-48
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• 2023

Background: The position of pitcher requires a lot of repetitive motion, and because of this, it is known that not only professional baseball players, but also middle and high school players are frequently exposed to injuries in baseball. The purpose of this study is to examine the differences in upper extremity muscle activity during repeated pitching and the activity of each muscle during repeated pitching by analyzing middle and high school pitchers, divided into groups by age. Methods: Twenty participants (10 middle school male students and 10 high school male students) were recruited for this research. The outcome measures included neuromuscular motor control, including the upper trapezius (UT), triceps brachii (TB), deltoid (DT), latissimus dorsi (LD), biceps brachii (BB), pectoralis major(PM), extensor carpi radialis(ER), and flexor carpi radialis (FR). Results: The two-way analysis of varaince (ANOVA) was used to compare the muscle activity variables between the middle school and high school students. The one-way ANOVA was used to compare the muscle activity variables within time differences each groups. Conclusion: Our results provided promising clinical evidence that guide for upper extremity muscles to increase pitching efficiency in middle and high school base ball players.

• 천문학회보
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• 제39권2호
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• pp.77.2-77.2
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• 2014

Questions of how our Milky Way evolves through the interaction with its environment have been constantly raised. One particularly interesting question is how the metallicity would change as our Milky Way goes through collision with HVCs. Because of the possibility of HVCs providing fuel for star formation in the Galactic disk, we simulate the collision between HVCs and the Galactic disk. More specifically, we trace how the Galactic metallicity changes throughout the process of HVCs colliding with our Milky Way based upon a specific scenario that HVCs are primordial gas left-overs from an ancient galaxy formation. Such mixing between metal-rich gas (disk) and metal-poor HVC can be traced by running numerical simulations with the FLASH code due to its capability of tracking down the abundance change of a specific element such as carbon at each time step of the hydrodynamic evolution. As for now, we give how this mixing depends on model parameters that we choose such as collision speed, initial metallicities, temperature and so on.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.398-401
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• 2001

There is explosive increase of traffic with economic growth and high level of civilization, and the increase causes so many complicated traffic problems. To solve these problem, the best way is expansion of road. bridges and some kind of traffic establishments. But this way need so many investment of time and money. So We must use the bounded roads and bounded establishments very effective way. To do so we have to gather the information about the road, vehicles, and etc. In this study, I will introduce you the way of gathering the information about vehicles, and transferring database server.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.86-92
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• 2010

A metal diaphragm compressor has been widely used for supplying a high pressures gas. This compressor mainly consists of gas oil space and metal diaphragm. Gas sucked in the gas space is compressed by an oscillating metal diaphragm existed between the gas and oil space. A non-return discharge and suction check-valve are components of the compressor that draw off the compressed oil and gas. Those components are self-actuated by differential pressures. Therefore, the rapid response and stable operating conditions are required. In the present study, to find out the dynamic behavior of the suction, discharge valve and diaphragm compressor, the unsteady flow field has been investigated numerically by using the unsteady two-way FSI (Fluid Structure Interaction) simulation method, $k-{\omega}$ turbulent model and mesh deformation.