• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.884-888
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• 2005

The interests of the government and civil business owner against the Light rail transit are increasing, it may be caused by the enterprise conception which does not consider a city circumstance that the construction plan is insensitively performed. This article present the forecast method of minimum transportation demand which secures a profitability. If It is in advance investigated the number of passenger using the existing traffic system of the area, it will be possible that the LRT project is planned on a realistic basis.

• 한국항공운항학회지
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• 제17권2호
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• pp.18-22
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• 2009

In this study, we surveyed the operating status of the Light Sport Aircraft(LSA) in Korea, and reviewed the minimum requirements of the airpark for LSA in other countries. Based on the information, we presented the airpark standards to ensure the safe take-off, landing, and operation of LSA in Korea.

• 한국도로학회논문집
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• 제19권3호
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• pp.45-55
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• 2017

PURPOSES: The objective of this study is to estimate required minimum spacing between Freeway IC for high-speed roadways. METHODS : Since high-speed roadways with over 140 km/h design speed do not exist in Korea, VISSIM Simulation Program was used for analysis. Acceleration noise and conflicts were selected for Evaluation Index. Standard deviation size for acceleration and deceleration was calculated by VISSIM to estimate acceleration noise. Conflicts were produced in areas between Freeway IC with SSAM. RESULTS : As a result, required minimum spacing was 6 km for acceleration noise analysis, while 5 km was deducted for conflict analysis. For Model Evaluation, with SAS, conflicts did not show much difference in 5~6 km area by 90% confidence interval. CONCLUSIONS : For acceleration noise, results showed lacking in its discrimination between index per Minimum Spacing. However, conflicts were valid in difference; required minimum spacing was 5 km by validation result.

• 한국항공운항학회지
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• 제29권2호
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• pp.94-99
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• 2021

UTM is an air traffic management ecosystem under development for autonomously controlled operations of UAS by the FAA, NASA, other federal partner agencies, and industry. They are collaboratively exploring concepts of operation, data exchange requirements, and a supporting framework to enable multiple UAS operations beyond visual line-of-sight at altitudes under AGL 500ft in airspace where air traffic services are not provided. Minimum Safe Altitude is a generic expression, used in various cases to denote an altitude below which it is unsafe to fly owing to presence of terrain or obstacles. The European drone regulation mentions that the UAS is maintained within 120 metres from the closest point of the surface of the earth during flight, except when overflying an obstacle. This study attempted to develop a minimum flight altitude database system. Based on domestic and international rules and regulations on setting the minimum flight altitude it is expected that it can be applied to the operation of aircraft and unmanned aerial system in UTM environments for specific area in Korea.

• 한국대기환경학회지
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• 제12권1호
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• pp.55-66
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• 1996

One-hour average concentrations of ground-level ozone from around 80 monitoring stations in Korea during 1991 to 1993 were analyzed to examine characteristics of the ozone concentration variations. Two types of variations were observed: one was for the Capital area typified by Kwanghwmun, and the other was for the south and east seashore region typified by Tongkwangyang. In the Capital area including Seoul, Inchon, Kyonggi-do and Chunchon, mean daily 1-hout maximum was the highest in June following high monthly averages in spring. But frequent precipitation prevented further rise of daily maximum in July and August even though there were frequent episodes of high concentration exceeding 100ppb. In the south and east seashore region, average concentration was the highest throughout the year, and daily maximum and minimum simultaneously changed owing to small contributions from photochemical reactions. The typical annual variation was spring peak, summer down, and fall rise. Spring peak accompanied an usual observations of background variations at remote sites in the Northern Hemisphere. Riess of average and daily maximum with lower daily minimum in fall were attributable to photochemical reactions.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2012년도 춘계학술발표대회논문집
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• pp.449-450
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• 2012

오늘날 컴퓨터와 정보통신 기술에 의해 생성된 디지털 맵(map)은 다양한 분야에서 응용 활용되고 있다. 이에 디지털 맵 제작 기술의 발전과 함께 선형 단순화(line simplification) 기법에 대한 연구가 활발하게 진행되고 있다. 이에 본 논문은 라인의 형상을 최대한 보존하기 위하여 최소영역오차(minimum area error, MAE) 구간을 이용한 혼합형 선형 단순화 기법을 제안한다. 기존의 선형 단순화 기법과의 비교 실험을 통하여, 제안하는 기법의 성능이 우수함을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.407-409
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• 2002

This paper proposes a process using the load shedding scenario method that determines the minimum local load shedding quantity considering the local DLC(Direct Load Control) potentials. So this method is applied to Kyung-In area and determined the load shedding of this area with comparison to its DLC potentials.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.139-142
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• 2005

Kim and Lee(2005) suggested Minimum Entropy Deconvolution(MED) to estimate the temporal sequence of the relative recharge. However this study by Kim and Lee(2005) was just related to the verification of the conceptual approach with MED. In this study, we try to characterize the applicability of MED in the case of spatially heterogeneous recharge (distance from recharge area). Simulated results were recorded with some specific sampling points. Estimated results from this study show higher than 0.8 in cross-correlation with the original recharge sequence.

• 한국통신학회논문지
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• 제33권5A호
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• pp.500-508
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• 2008

Direct-sequence ultra-wideband(DS-UWB) system is being considered as one of promising transmission technologies for wireless personal area networks(WPANs). Due to relatively low spreading factors and huge bandwidth of transmit signal, a DS-UWB receiver needs to be equipped not only with a rake receiver but also with an equalizer, of which the equalizer is not required for traditional direct-sequence code division multiple access(DS-CDMA) systems. The number of rake fingers is limited in practice, influencing the performance of the subsequent equalizer. In this paper, we derive a decision feedback equalizer(DFE) for DS-UWB systems based on the minimum mean square error(MMSE) criterion, and investigate the impact of various parameters on the DFE performance in realistic scenarios. In particular, we propose an approach to improving the performance of the DFE using additional channel estimates for multipaths not combined in the rake receiver, and discuss how the accuracy of channel estimation affects desirable DFE configuration. Moreover, we present simulation results that show the impact of turbo equalization on the DFE performance.

• 대한교통학회지
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• 제12권3호
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• pp.15-27
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• 1994

A mathematical model and its solution algorithm are proposed for computing the capacity of terminal control area. The model is built based on dynamics of aircraft flying on pre-established approach path and its solution algorithm employs a numerical method. The model computes the minimum separation of two aircraft at the entry fix of the terminal control area, which assures that air traffic separation rules are not violated during the approach phase, thereby computes the capacity. The model might be applied for designing approach paths for a new airport, for rearranging paths of an existing airport or establishing approach control procedures.