• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1549-1551
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• 2002

현재 게이트 길이가 100nm 이하의 MOSFET 소자를 구현할 때 가장 대두되는 문제인 short channel effect를 억제하는 방법으로 제안된 소자 중 하나가 double gate (DG) silicon-on-insulator (SOI) MOSFET이다. 그러나 DG SOI MOSFET는 두 게이트간의 align과 threshold voltage control 문제가 있다. 본 논문에서는 DG SOI MOSFET에서 이상적으로 게이트가 align된 구조와 back 게이트가 front 게이트보다 긴 non-align된 구조가 subthreshold 동작 영역에서 impact ionization에 미치는 영향에 대해 시뮬레이션을 통하여 비교 분석하였다. 그 결과 게이트가 이상적으로 align된 구조보다 back 게이트가 front 게이트보다 긴 non-align된 구조가 게이트와 드레인이 overlap된 영역에서 impact ionization이 증가하였으며 게이트가 각각 n+ 폴리실리콘과 p+ 폴리실리콘을 가진 소자에서 두 게이트가 같은 work function을 가진 소자보다 높은 impact generation rate을 가짐을 알 수 있었다.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E4
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• pp.215-221
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• 2002

The real-time modeling system, named AirWatch System, has been developed to evaluate the environmental impact from a large source. It consists of stack TMS (TeleMetering System) that measures the emission data from the source, AWS (Automatic Weather Station) that monitors the weather data and computer system with the dispersion modeling software. The modeling theories used in the system are Gaussian plume and puff models. The Gaussian plume model is used for the dispersion in the simple terrain with a point meteorological data while the puff model is for the dispersion in complex terrain with three dimensional wind fields. The AirWatch System predicts the impact of the emitted pollutants from the large source on the near-by environment on the real -time base and the alarm is issued to control the emission rate if the calculated concentrations exceed the modeling significance level.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.522-522
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• 2000

In this paper, two pre-filtering techniques are presented for accurately estimating the impact location of a loose part. The reason why a pre-filterng technique Is necessary in a Loose Part Monitoring System is that the effects of background noise on the signal to noise ratio (SNR) can be reduced considerably resulting in improved estimation accuracy. The first method is to take d moving average operation in the time domain. The second one is to adopt band-pass filters designed in the frequency domain such as a Butterworth filter, Chebyshev filter I & II and an Elliptic Filter. To show the effectiveness, the impact test data (signals) from the YGN3 power plant are first preprocessed and then used to estimate the loose pan impact position. Resultantly. we observed that SNR is much improved and the average estimation error is below 7.5%.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.113-125
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• 1998

The amount of mercury emitted from an incinerator depends on the properties of waste, combustion condition, and control devices. Mercury concentration in air proportionates to the increase of incinerator installation. The purpose of this study is to provide a method for determination of mercury emission factor which can predict the amount of mercury emitted from each incinerator specifically. Case study was performed for N municipal waste incinerator. Based on the method presented in this paper, we obtained mercury emission factor as 1.85~1.95 g Hg/t at N Municipal Waste Incinerator and this result was regarded as reasonable when compared with existing mercury emission factor in reference cases. Fluorescent lamps turned out to be the most important source(44.4%) of mercury in municipal waste and its amount will tend to increase, while batteries become less significant. In addition, medical waste is one of the major source of mercury.

• Journal of Environmental Impact Assessment
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• v.18 no.6
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• pp.411-417
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• 2009

Lately the master plan for the Four Major Rivers Restoration Project has been released by the Ministry of Land and Maritime Affairs and relevant ministries. According to the master plan compared with the interim report made on 15 December 2008, the number of weirs for irrigation has increased from 5 to 16, the amount of dredging has increased from 220 million cubic metres to 570 million cubic metres, and the total cost estimated has increased from 14 trillion won to 22 trillion won. A critical review of the master plan by some research group will be summarized focused upon budget, objectives, securing water resource, dredging, and flood control etc. After various experts' forums and field surveys, it is concluded that the government should implement a joint-research program on assessing the impact of the project together with experts and citizens' groups as co-partners, in order to truly save or restore the four major rivers.

• Journal of Environmental Impact Assessment
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• v.22 no.5
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• pp.529-536
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• 2013

인도네시아 정부의 아젠다21은 지속가능한 환경을 유지하기 위한 노력을 지원하는 정부-기업-시민 3자 시스템이다. 국가의 경제개발과 환경적 조화를 이루는 것이 중요하다는 것을 보여주는 국가의 의지이다. 인도네시아는 대기질 관리가 매우 중요하며 도시대기질관리전략은 1992년 대도시환경개성프로그램으로 채택되었다. 도시대기질프로그램(UAQP)는 '푸른하늘'을 목표로 하며 UAQP는 각 전략단계에 대기오염의 원인을 찾아내고 실행전략으로 유도한다. 아젠다21을 대기질 유지를 위해 수행하는 좋은 예이며 푸른하늘전략은 지속가능한 환경을 유지하기 위한 중요한 프로그램이다.

• Journal of Biosystems Engineering
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• v.22 no.1
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• pp.49-58
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• 1997

Finding of internal quality is crucial for getting under control quality of watermelon after harvest. A maturity sensing device of watermelon using repulsion characteristics was developed and evaluated. In this study, five different sensing probes were used to detect the physical changes after impact on watermelons. Total 15 watermelons were tested and evaluated into two classes: ripe and unripe. It was difficult to detect the overripe watermelons using the proposed sensor. Therefore, the results showed that the developed sensor could be used to separate unripe watermelons after harvest. The results from this study are summarized as follows. 1. It was successful to distinguish between the ripe and unripe watermelon by sensing the elastic characteristics on impact. 2. The hemisphere was best for the shape of sensing part because the hemisphere concentrate stress in impact part. 3. Among the five type developed sensor, the 1, 2, 3. 5-type sensor showed good character in distinguishing between ripe and unripe watermelon.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.237-238
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• 2016

Rework is a major cause that adversely affects the performance of a construction project, such as schedule delay or cost overrun. In order to prevent rework, research has been mainly conducted to analyze the cause of rework, but limited to quantitatively measure cost of rework and analyze its impact on project performance. Therefore, this paper aims to analyze impact of rework cost using 369 rework items collected from 3 construction site. This research is expected to accurately determine control target of rework and to improve efficiency of business operations in construction project.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.249-250
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• 2018

To control the floor noise generated in the apartment building, a method of reinforcing the floor at the floor is applied. However, since existing buildings are difficult to reinforce upper generations, the ceilings of lower generations should be reinforced. The purpose of this study is to analyze the reduction effect by measuring the impact noise after reinforcing the floor soundproofing material on the ceiling of the existing building. In order to ensure the economical efficiency and flame retardancy of the products used as building interior materials, the existing polyurethane foam was impregnated with mineral to prepare test specimens and attached to the concrete slab surface. As a result, it was shown that heavy impact sound can reduce 2dB~5dB and light impact sound can reduce 4~8dB.

• Journal of the Korea Safety Management & Science
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• v.3 no.1
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• pp.127-137
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• 2001

Because of the inherent flexibility in their design for improved material properties, composites have wide applications in aerospace vehicles and automobiles. The purpose of this study is to investigate the energy absorption characteristics of CFRf (Carbon Fiber Reinforced Plastics) tubes on static and impact tests. Static compression tests have been carried out using the static testing machine(Shin-gang buckling testing machine) and impact compression tests have been carried out using the vertical crushing testing machine. When such tubes were subjected to crushing loads, the response is complex and depends on the interaction between the different mechanisms that control the crushing process. The collapse characteristics and energy absorption were examined. Trigger and interlaminar number affect the energy absorption capability of CFRP tubes.