• 한국전자파학회논문지
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• 제18권9호
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• pp.1077-1082
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• 2007

본 논문에서는 3${\sim}$10 GHz대 통신용 초광대역 시스템이 3.5 GHz대 고정(fixed) WiMAX(Worldwide Interoperability for Microwave Access)에 미치는 간섭 영향에 대해 고찰하였고, WiMAX에 미치는 잠정적인 간섭을 줄이기 위해 초광대역 시스템의 송신 전력을 제어하는 방법을 제안하였으며, 몬테카를로 시스템 레벨 시뮬레이션을 통해 간섭 저감 효과를 분석하였다. 간섭 영향은 단위 면적 1$km^2$내에 존재하는 다수의 초광대역 시스템과 단일 WiMAX 수신기를 가정하였을 때, 초광대역 시스템의 간섭에 의한 WiMAX의 outage 확률로 평가하였으며, 결과의 일례로써 초광대역 시스템의 밀도가 20$devices/km^2$이고 송신 전력 제어 동적 출력 범위가 30 dB일 때, 송신 전력 제어 방법을 적용한 경우 간섭 저감 방법을 적용하지 않는 경우보다 초광대역 시스템의 간섭에 의한 WiMAX의 outage 확률이 42 % 감소되는 효과를 보였다. 결론적으로 제안된 송신 전력 제어 방법은 초광대역 시스템이 WiMAX에 미치는 간섭 영향을 저감시린 수 있음을 보였다.

• 한국방재학회 논문집
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• 제7권5호
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• pp.111-118
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• 2007

최근에 들어와 가로등에 의한 감전사고가 지속적으로 발생하고 있다. 특히 집중호우로 인해 가로등이 침수될 경우 누전에 의한 감전 사고는 매우 높다. 전기감전사고가 발생할 경우 사고전압을 분석해 보면 주로 220V의 저압시설물에서 발생되고 있으나 이에 대한 위험성을 충분히 인식하지 못하고 있는 실정이다. 가로등 시설물의 사용전압 220V는 주로 일반인이 쉽게 접촉할 수 있는 도로변에 시설되어 있기 때문에 감전사고의 위험성은 매우 높은 편이다. 그러나 가로등 침수로 인해 누전이 발생했을 경우 누전체에서의 거리변화에 따른 수중전위분포가 인체에 미치는 영향을 연구하는 사례는 미약한 실정이다. 본 논문에서는 수중에서 누전이 발생했을 경우에 인체에 미치는 영향과 수중전위분포를 분석하고 수중에서 누전체와의 거리 및 깊이에 따른 변화가 어떻게 인체에 영향을 주는지 실험을 통하여 감전경로와 감전메카니즘을 비교 분석하고자 한다.

• 한국방재학회 논문집
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• 제7권1호통권24호
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• pp.67-72
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• 2007

본 연구에서는 토사에 대한 질량보존의 법칙을 이용하여 자연유역 내 토양의 침식 및 퇴적 잠재능을 산정할 수 있는 모델을 개발하였다. 이 프로그램은 각 셀 별 토사에 대한 질량보존의 법칙을 적용하여 GIS환경하에서 구동 가능하도록 구성되어있으며 셀 별 토사발생량은 RUSLE 공식을 이용하여 산정하였다. 토양의 침식 및 퇴적 잠재능은 토사의 유출량과 유입량의 차에 의해 각 셀이 침식되거나 퇴적된다는 질량보존의 법칙을 이용하여 산정하였다. 질량보존의 법칙을 적용하기 위한 셀 별 토사유출량은 토사발생량과 토사전달률을 곱하여 산정하였으며 이 토사 유출량이 흐름방향 알고리즘에 의해 결정되는 하류 셀의 토사유입량이 된다. 본 연구에서 개발된 모델을 이용하여 국내 소유역에 대해 적용하였으며 그 결과를 실측치와 비교함으로써 모델을 검증하였다.

• 환경정책연구
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• 제8권4호
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• pp.171-198
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• 2009

국가 온실가스 감축목표 설정과 더불어 이를 어떻게 달성해야 하는 이른바, 부문 간 책임배분의 문제는 주요 국가과제 중 하나다. 본 연구에서는 책임배분의 원칙 및 기준을 설정하고 할당지수를 이용해 부문 간 책임배분방안을 제시하였다. 주요 기준으로서 부문 간 저감잠재성, 배출증가율, 지불능력을 고려하였다. 본 연구에서는 저감잠재성만을 기준으로 할당할 경우와 비교분석하고 매우 상이한 결과를 도출될 수 있음을 제시하였다. 본 연구에서 제시한 방법론은 비용효율적인 동시에 사회적으로 수용 가능한 책임배분을 제시한 것으로서, 향후 국민경제 파급효과 분석 등을 거쳐 보다 면밀히 검토되어야 할 것이다.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.775-778
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• 2008

In general, forecast tsunami heights announced for tsunami warning are computed by using a linear tsunami model with coarse grids which leads the underestimation of inundation area. Thus, an accurate tsunami inundation map corresponding to the forecast tsunami height is indispensible for an emergency evacuation plan. A practical way to construct a relatively accurate tsunami inundation map was proposed in this study for the quantitative forecast of inundation area. This procedure can be introduced as in the followings: The fault dislocations of potential tsunami sources generating a specific tsunami height near an interested area are found by using a linear tsunami model. Based on these fault dislocations, maximum inundation envelops of the interested area are computed and illustrated by using nonlinear inundation numerical model. In this study, the tsunami inundation map for Imwon area was constructed according to 11 potential tsunami sources, and the validity of this process was examined.

• Earthquakes and Structures
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• 제20권3호
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• pp.337-351
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• 2021

On September 12, 2016, the Gyeongju earthquake occurred in the south-eastern region of the Korean peninsula. The event was ranked as the largest magnitude earthquake (=5.8) since instrumental recording was started by the Korean Metrological Administration (KMA) in 1978. The objective of this study is to provide information obtained from the 2016 Gyeongju earthquake and to propose a procedure estimating seismic risk of a typical old RC building for past and potential earthquakes. Ground motions are simulated using the point source model at 4941 grid locations in the Korean peninsula that resulted from the Gyeongju earthquake and from potential future earthquakes with the same hypocenter considering different soil conditions. Nonlinear response history analyses are conducted for each grid location using a three-story gravity-designed reinforced concrete (RC) frame that most closely represents conventional old school and public buildings. Then, contour maps are constructed to present the seismic risk associated with this building for the Gyeongju earthquake and potential future scenario earthquakes. These contour maps can be useful in the development of a mitigation plan for potential earthquake damage to school and public buildings at all grid locations on the Korean peninsula.

• 산업경영시스템학회지
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• 제45권4호
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• pp.21-30
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• 2022

To mitigate the environmental impacts of the energy sector, the government of South Korea has made a continuous effort to facilitate the development and commercialization of renewable energy. As a result, the efficiency of renewable energy plants is not a consideration in the potential site selection process. To contribute to the overall sustainability of this increasingly important sector, this study utilizes the Black-Scholes model to evaluate the economic value of potential sites for off-site wind farms, while analyzing the environmental mitigation of these potential sites in terms of carbon emission reduction. In order to incorporate the importance of flexibility and uncertainty factors in the evaluation process, this study has developed a site evaluation model focused on system dynamics and real option approaches that compares the expected revenue and expected cost during the life cycle of off-site wind farm sites. Using sensitivity analysis, this study further investigates two uncertainty factors (namely, investment cost and wind energy production) on the economic value and carbon emission reduction of potential wind farm locations.

• 한국환경복원기술학회지
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• 제26권6호
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• pp.21-32
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• 2023

The Environmental Impact Assessment (EIA) plays a pivotal role in predicting the potential environmental impacts of proposed developments and planning appropriate mitigation measures to minimize effects on species. However, as concerns over biodiversity loss rise, there's ongoing debate about the efficacy of these mitigation plans. In this study, we utilized data from EIAs and post-environmental impact surveys to understand the trends in biodiversity during construction and operation phases. By examining 30 urban development projects, we categorized species richness indices of mammals, birds, amphibians, and reptiles into pre-construction, during construction, and post-construction operational stages. The biodiversity trends were analyzed based on the rate of change in these indices. The results revealed three distinct biodiversity change patterns: (A) An initial increase in biodiversity indices post-development, followed by a gradual decline over time; (B) a sustained increase in biodiversity as a result of mitigation measures; and (C) a continuous decline in biodiversity post-development. Furthermore, all species exhibited a higher rate of biodiversity decline during the construction phase compared to the operational phase, with mammals showing the most significant rate of change. Notably, the biodiversity change rate during operation was generally lower than during construction. In particular, mammals seemed to be most influenced by mitigation measures, displaying the smallest rate of change. This study provides empirical evidence on the efficacy of mitigation measures and deliberates on ways to enhance their effectiveness in minimizing the adverse impacts of urban development on biodiversity. These findings can serve as foundational data for addressing terrestrial biodiversity reduction.

• 국제초고층학회논문집
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• 제7권1호
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• pp.85-93
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• 2018

The design of a supertall building poses many challenges to the architect and engineer. Using Jeddah Tower as a case study; this paper intends to discuss a few of those challenges specifically related to the arrangement of programmed spaces in the tower, their functional connection by means of the vertical transportation system and physical connection with shafts which introduces the potential for stack effect in the building. The measures applied in response to and mitigation of these issues are discussed.

• 한국도로학회논문집
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• 제17권6호
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• pp.117-126
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• 2015

PURPOSES : This study prioritizes potential technology for establishing a safe work zone environment on roadways. We consider almost all conceivable technologies that enable mitigation of unexpected accidents for both road workers and drivers. METHODS : This study suggests a methodology to set the priority of potential technology for establishing a safe work zone environment by using the analytical hierarchy process (AHP). For this purpose, the AHP structure was first developed. Thereafter, a web-based survey was conducted to collect experts' opinions. Based on the survey results, weights associated with the relevant criteria of the developed structure were estimated. With the consistency index (CI) and consistency ratio (CR), we verified the estimated weights. In addition, a sensitivity analysis was performed to confirm whether the estimated weights were reliable. We finally proposed the priority for potential technology for establishing a safe work zone environment on roadways. RESULTS : In the first level, safety technology has the highest priority, and real-time information delivery for work zone, hazard warning for drivers, and temporal automated operation for traffic facilities were selected in the second level of hierarchy. CONCLUSIONS : The results imply that establishing the priority will be useful to establish a future road map for improving the work environment for road workers and drivers by employing appropriate protection facilities and developing safety systems.