• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
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• pp.348-350
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• 2006

In this paper, we design a new controller for an ultra-precision positioning system. In general, time optimal control enables to reach a target position faster than others. However it shows a weakness to chattering effect. In order to solve the problem, a new control algorithm based on sliding mode control is proposed. The suggested controller is composed of LQR control and sliding mode control. By performing some simulations, we prove that the proposed controller is more robust than time optimal control under the circumstance of parameter uncertainties and external disturbances.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.381-382
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• 2018

무접합 나노선 터널 전계 효과 트렌지스터(junctionless nanowire tunnel field-effect transistor; JLNW-TFET)에서 소스(p+), 채널(i), 드레인(n) 물질으로 실리콘 및 게르마늄을 사용하여 이 구조에 대한 문턱전압 이하 기울기(subthreshold swings; SS)와 구동전류를 관찰했다. 소스-채널을 게르마늄-실리콘일 때 실리콘-실리콘, 실리콘-게르마늄, 게르마늄-게르마늄 구조보다 구동전류가 최대 1000배 증가하였고, 실리콘-실리콘 구조가 다른 구조에 비해 최소 SS가 최대 5배 이상 감소하였다.

• 한국응용과학기술학회지
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• 제4권1호
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• pp.91-97
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• 1987

Because of its more complete hydrolysis and rapid absorption, MCT is expected its usefulness in the diets of patients with malabsorption syndrom. Also, several authors reported that serum cholesterol level was lower after MCT feedings. In this study, rate of each experimental group were fed for 4weeks with 20％ MCT, 20％ corn oil, mixed diet of 10％ MCT and 10％ corn oil, mixed diet of 17％ corn oil and 3％ shortening. After experimental diet, it was measured to growth rate and serum cholesterol, triglyceride and phospholipid level. The results were as follows; 1. The body weight gain was the lowest in MCT group and others were lower than control group. 2. Serum total cholesterol level was the lowest in corn oil group and others were significantly lower than control group. Free cholesterol level was lower in all experimental groups than control group too. 3. Serum HDL-cholesterol level was significantly higher in all experimental groups than control group. 4. The ratio of VLDL, LDL-Cholesterol to HDL-Cholesterol was significantly lower in all experimental groups than control group. 5. Serum triglyceride level was higher in all experimental groups than control group. Serum phospholipid level was significantly in only mixed diet group of corn oil and shortening than control group. 6. The ratio of total cholesterol to phospholipid was significantly lower in corn oil diet group than control group.

• International Journal of Control, Automation, and Systems
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• 제3권spc2호
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• pp.341-345
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• 2005

Part-I of this two-part paper develops an optimal algorithm for transient stability control to coordinate the preventive actions and emergency actions for a subset of contingencies with an identical unstable mode. In this portion, several subsets of contingencies having dissimilar unstable modes are dealt with. Preventive actions benefiting a subset of contingencies may go against the stability of others, thus coordination among the optimal schemes for individual subsets is necessary. The coordination can be achieved by replacing some preventive actions with contingency-specified emergency actions. It is formulated as a classical model of economic dispatch with stability constraints and stability control costs. Such an optimal algorithm is proposed based on the algorithm in Part-I of the paper and is verified by simulations on a Chinese power system.

• 교육녹색환경연구
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• 제6권2호
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• pp.53-65
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• 2007

Our society is changing into the society of knowledge and information since the advent of 21st century. This may require that schooling need to have a new paradigm. Korea has already entered into the aging society with the help of various population control policies such as birth control from 1960s, and is expecting to go into the so called ultra- aging society. Elementary and middle schools have been facing the rapid decrease in the number of students since the mid-1980s, which high schools are now confronting with. The present study investigates how to effectively utilize extra classrooms at schools. The present study offers eight basic directions that may help establish the utilization planning of extra classrooms. One direction is offering an appropriate space utilization environment, another is to present a plan for having special classrooms. Others are having multi-purpose classrooms, management on the unified rooms for library and audio-visual teaching, securing facilities rooms for the school staff. And others are the planning of the diversion of living space for improving sanitation and the provision of meals, the necessity of the extension or rebuilding of school buildings for other uses according to school development schemes, the utilization planning for community residents to which each school belong.

• 한국분무공학회지
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• 제20권3호
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• pp.149-155
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• 2015

With increasing of GDP, the registration number of passenger cars has exceeded 20 million last year in Korea. Especially, the registration number of the diesel engine vehicles has been increasing. However, the WHO(World Health Organization) IARC (International Agency for Research on Cancer) has reported that diesel engine exhaust gas is an one of HAPs, which has carcinogenic for human, and they have designated it to Group 1. To solve this problem, exhaust gas from diesel engines has to be controlled. Thus, it has been controlling by European regulatory standard in Korea. On the other hand, in order to meet the enhanced emission regulations, all manufacturing company applied $NO_x$ control device to vehicles such as EGR (Exhaust Gas Recirculation), SCR (Selective Catalytic Reduction) and so on. However, these devices (EGR, SCR) were operated by difference reaction mechanism respectively, and the composition of exhaust gas would be differenced from that of them. In this study, it was conducted to evaluate variety characteristics on changing of exhaust gas composition by each $NO_x$ control device, and the heavy duty diesel trucks were chosen as experimental vehicles. From the result, it revealed that vehicles (with EGR) were discharged higher THC as 52.5% than that of others (with SCR). However, it did not followed that trend, in the case of CO; it was discharged as 57.2% lower than that of others (with SCR). In the future, these data would be used to apply to efficient $NO_x$ control device for meeting to EURO 6.

• 환경위생공학
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• 제7권1호
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• pp.35-44
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• 1992

This paper included the preventive measures and the prospect of lake eutrophication in korea. All pollution control techniques must be applied after the characteristics of the lakes are surveyed sufficlenty, Most of Korean lakes are the large man-made ones and their characteristics are different from those of natural ones in foreign nation. Some of many techniques for natural lakes can be applied in our lakes also, others must be revised. Lake water quality can be ameliorated only by systematic researches and technologies because lake ecosystem is very complicated. It is impossible to improve water quality with fragmentary and shortterm projects.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.995-1000
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• 2002

This paper presents general concept of DC switch gear(DCSWGR). Normally, DCSWGR consist of Digital protection unit(DPU), High Speed Circuit Breaker(HSCB), Disconnect Switch (DS), Programmable Logic Control(PLC), Auxiliary Relays and etc. Most of the components has its special characteristics and their interface between each others are various and complex. In this paper every constituent general design are preceded and interface between each component are examined. And also DCSWGR operation logic with logical diagram including interlock signal are introduced.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.312-314
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• 2001

Whenever the accidents occur in the rail way areas, their prompt recovery is very important. The individual way has been used to resolve these accident by direct visiting the site and reporting to others of the person who cares for these cases. As a result, we are planing to operate the MTS (Multimedia Transmission System) for a timely information's transmission to the related peoples in the central control center by transforming the picture information on the accident-site to the digital information.

• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1279-1284
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• 2005

The effects of 3 different strains of Japanese koji (Aspergillus oryzae, A. sojae and A. awamori) in the solid-state fermentation (SSF) of sugarcane bagasse mixed with wheat bran on chemical composition, energy, in vivo digestibility and preference of the fermented bagasse feeds (FBF) in goats were investigated. Diets consisted of lucerne hay cube (basal diet) and unfermented bagasse feed (control), FBF with A. oryzae (O), FBF with A. sojae (S) or FBF with A. awamori (A), which were mixed in a total ration of 7:3 (w/w DM). Three Nubian does were fed each of the diets, i.e. control, O, S and A in the 4 consecutive periods for digestion trials (21-day each). The goats were also used for preference trials (30-min each) of O, S and A. The O was significantly higher in CP content than others (p<0.05). The crude fiber (CF), ADF and cellulose contents of control were significantly lower than those of other diets (p<0.05). The S had significantly higher CF digestibility than control (p<0.05), and it revealed the largest value of all. Digestibilities of NDF, ADF and cellulose in S were significantly higher than those of control (about 10, 18 and 18%, respectively, p<0.05). The DE of S was significantly higher than that of others (p<0.05), though there were no significant differences in DCP and TDN between control and S. The results of preference trials demonstrated that the average intake rate was not significantly different among diets, but O and S are likely to be preferable to A (p<0.1). It was concluded that the SSF of bagasse feeds by Japanese koji can improve the fiber digestion, especially NDF, ADF or cellulose in goats, and there is a marked effect in the feed containing A. sojae, which may lead to the improvement of DE.