• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.17 no.2
• /
• pp.18-22
• /
• 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.

• International Journal of Highway Engineering
• /
• v.19 no.3
• /
• pp.45-55
• /
• 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.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.29 no.2
• /
• pp.94-99
• /
• 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.

• Journal of Korean Society for Atmospheric Environment
• /
• v.12 no.1
• /
• pp.55-66
• /
• 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.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2012.05a
• /
• pp.449-450
• /
• 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.

• Proceedings of the KIEE Conference
• /
• 2002.07a
• /
• pp.407-409
• /
• 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.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2005.04a
• /
• pp.139-142
• /
• 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.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.5A
• /
• pp.500-508
• /
• 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.

• Journal of Korean Society of Transportation
• /
• v.12 no.3
• /
• pp.15-27
• /
• 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.

• Journal of People, Plants, and Environment
• /
• v.22 no.6
• /
• pp.641-651
• /
• 2019

The purpose of this study is to derive institutional improvement methods for promoting the Damaged Area Restoration Project in greenbelts. The current status of greenbelts in Gyeonggi-do, where greenbelts are extensively distributed was analyzed, and the relevant laws and regulations were reviewed to suggest measures to promote the restoration project. The area of damaged areas within greenbelts in Gyeonggi-do was 6,121,024 m², accounting for about 0.52% of the total area of greenbelts, and more than 80% was found to be located in Namyangju (55.49%), Hanam (16.48%), and Siheung (8.68%). Various measures to improve the policy were examined as follows: reducing the minimum size of the restoration project area; adjusting baseline of recognizing range of damaged areas; introducing the right of claim for land sale; allowing long-term unexecuted urban parks to be replaced as alternative sites for parks and green spaces; simplifying administrative procedures; and allowing public participation. All of them are expected to promote the restoration project within greenbelts. In results, when the minimum size of area for the restoration project was reduced from 10,000 m² into 5,000 m², 3,000 m² and 2,000 m², the ratio of the number of combinable lots to the total number of lots increased from 4.4% to 18.8%, 38.8%, and 55.9% respectively in Namyangju. Morever, when the recognizable ranges of the restoration project were extended to the structures obtaining building permit as of March 30, 2016 and obtaining use approvals before December, 2017, the number of applicable lots increased by 5.1% and 9.2% respectively.