• Nuclear Engineering and Technology
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• 제56권6호
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• pp.2039-2049
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• 2024

The radioactive pollutant could migrate to the downstream urban area under the action of atmospheric dispersion due to the turbulent mixing under actual pollution accidents. A scenario in which radioactive contaminants from the upstream (for example, a nearshore nuclear power plant accident) migrates to the downstream urban blocks have been considered in this study. Numerical simulations using computational fluid dynamics (CFD) are then conducted to investigate the effects of the urban morphology (building packing density and layout) on the atmospheric dispersion of radioactive pollutants in this scenario. The building packing density and structure can significantly affect urban areas' mean flow pattern and the turbulent kinetic energy (TKE). The flow pattern and the TKE distribution influence the radioactive pollution dispersion. It is found that the radioactive pollution at the urban canyons is significantly affected by the vertical transport at the canyon. A comparison of the distributions of radioactive and traditional non-radioactive pollutants is also provided.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.591-592
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• 2007

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2010년도 춘계학술대회 논문집
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• pp.189-191
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• 2010

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2004년도 Sharing Experience of Human and Ecological Risk Assessment and Management in Asia/Pacific Region
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• pp.40-40
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• 2004

• Structural Engineering and Mechanics
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• 제30권3호
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• pp.351-368
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• 2008

The purpose of this paper is to propose a simple analysis method of axial deformation of base-isolation rubber bearings in a building subjected to earthquake loading and present its applicability to the analysis of the bound of the aspect ratio of base-isolated buildings. The base shear coefficient is introduced as a key parameter for the bound analysis. The bound of the aspect ratio of base-isolated buildings is analyzed based on the relationship of the following four quantities; (i) ultimate state of the tensile stress of rubber bearings based on a proposed simple recursive analysis for seismic loading, (ii) ultimate state of drift of the base-isolation story for seismic loading, (iii) ultimate state of the axial compressive stress of rubber bearings under dead loads, (iv) prediction of the overturning moment at the base for seismic loading. In particular, a new recursive analysis method of axial deformation of rubber bearings is presented taking into account the nonlinear tensile behavior of rubber bearings and it is shown that the relaxation of the constraint on the ultimate state of the tensile stress of rubber bearings increases the limiting aspect ratio.

• 한국터널지하공간학회 논문집
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• 제19권1호
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• pp.11-27
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• 2017

서울시 등의 국내 주요 도심은 지역적 팽창에 따라 도로망 체계가 급격하게 발전하였고 도시민이 안락하고 풍요로운 생활을 영위하도록 전력, 통신, 상수도, 하수도, 냉 난방관로, 가스관 등이 무분별하게 개별 매설되었으며 비효율적으로 개별 관리되고 있다. 국토계획법에서는 Life-Line을 공동 수용함으로써 도로의 반복 굴착을 줄이고 도시 미관의 개선, 포장 내구성 향상에 따른 주행성능 향상 그리고 원활한 교통소통 등을 기대하는 도시계획 시설물로 공동구를 정의하고 있다. 최근 기존 도심지의 재정비 측면에서 쾌적한 도시공간 조성, 지하공간 이용 효율과 도로관리 효율 향상, 지진 및 도로함몰에 대한 재난안전성, 스마트 그리드와 전기자동차 보급과 같은 미래 생활환경 변화에 대한 신속한 대응 등을 기대할 수 있는 기존 도심지의 공동구 설치 필요성이 증가하고 있으나 국내에 설치된 모든 공동구는 신도시 개발에 따라 계획된 Life-Line을 모두 수용하도록 설치한 개착식 공동구 형태이다. 기존 도심지에서는 현재 가동중인 모든 Life-line을 모두 수용할 수 없으므로 도심지 유형별 공동구 설치 타당성 평가시스템을 활용한 설계용량 최적화 등의 새로운 연구가 필요하다. 본 연구는 신도시 공동구를 탈피하고 기존 도심지를 대상으로 평가지표에 의한 정량적 평가모델을 제시 하는 등 유형별 타당성 평가시스템을 세분화하며 정량적 평가시스템의 구현이 가능한 프로그램을 개발해 궁극적으로 도심지 공동구 활성화에 기여하고자 한다.

• 한국지리정보학회지
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• 제17권2호
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• pp.1-14
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• 2014

본 연구에서는 효율적인 도시 관리를 위하여 대구시 도시공간구조의 시계열적 공간변화 특성을 도시계획과 연계하여 분석하였다. Getis-Ord $G_i^*$ 방법론을 활용하여 1970년부터 2010년까지 대구시의 도시성장과정을 분석한 결과, 대구시는 도시성장단계 중에서 역도시화 단계에 해당하는 것을 확인하였다. 하지만 대구시는 도시계획적 차원에서 다핵도시를 지향함으로써 역도시화가 나타난 2000 이후의 도시성장단계는 더 이상 전통적인 이론으로 설명하기 어려웠다. 이에 2000년 이후 다핵권역의 세부적인 공간구조변화를 분석하기 위하여 인구, 지가, 고용 요인의 변화를 바키측 정치를 이용하여 분석하였다. 분석결과 대구시는 다핵화가 진행 중이었으며 도심권역과 칠곡권역은 분산형, 안심 달서권역은 집중형, 성서권역은 집중 분산형태로의 공간구조변화가 나타났다. 지역에 따라 다른 도시공간구조를 나타내는 도시의 효율적인 관리를 위해서는 권역별 특성을 고려한 도시계획과 개발계획이 필요한 것으로 판단된다.

• 국제초고층학회논문집
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• 제12권2호
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• pp.179-193
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• 2023

It is undeniable that urban greenspace is the soul of a city. Conventional urban greenspace such as parks, community gardens, playgrounds etc. located within a city reduce the negative effects of pollution, play a major role in the survival of the urban ecosystem, and promote healthy lifestyles. Today, 55% of the world's population lives in urban areas, which is expected to increase to 68% by 2050. Projections show that urbanization and the gradual migration to urban areas combined with the fast growth of the world's population, could add another 2.5 billion people to urban areas by 2050 and almost 90% of this increase will take place in Asia(UN, 2018). As a result, many plots in the cities are and will continue to be occupied with buildings to provide residential support to the increased population. This will dangerously decrease urban greenspaces. Moreover, worldwide, food crisis, energy crisis, and social crisis is posing a great threat to the existence of mankind. Additionally, the COVID - 19 has introduced a new lifestyle where from work culture to community configuration has drastically transformed. In this scenario, residential buildings will have to serve more than just providing privacy and shelter. As urban greenspaces are being occupied by concrete residential buildings, these buildings will have to compensate for the percentage of urban green they are destroying and the issues they are imposing in the process. The goal of this thesis is to design, architecturally define and, categorize comprehensive 'sustainable Greenspace'(S.G.S) for the multi-family housing scenario. These will be different than the conventional green (veranda, rooftop green) we commonly see in residential buildings. An old, dilapidated apartment building will be the target of remodeling to fulfill the purpose of this thesis.

• 한국환경과학회지
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• 제25권1호
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• pp.31-40
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• 2016

The purpose of this study was to analyse the runoff characteristics of non-point pollution sources in an urban watershed and determine the effectiveness of newly installed riverwater treatment system to reduce water pollution caused by storm runoff in the urban watershed. The results of this study showed that the levels of BOD5 and suspended solid were highly influenced by first-flush effect and the pollutant load of those two parameters were also very high in the urban watershed. Meanwhile, the effectiveness of riverwater treatment system to reduce the levels of BOD5 and suspended solid was relatively high, but those to reduce the levels of T-N and T-P was low, which needs some additional unit treatment process such as filtration and coagulation. Nonetheless, the riverwater treatment system tested was relatively simple in installation and operation, effective in removing many water pollutants and, most importantly, does not require much space as other treatment systems, so it could be an attractive alternative option to reduce riverwater pollution caused by storm runoff in urban watersheds.

• 대한원격탐사학회지
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• 제36권4호
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• pp.609-626
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• 2020

Satellite-based land surface temperature (LST) has been used as one of the major parameters in various climate and environmental models. Especially, Moderate Resolution Imaging Spectroradiometer (MODIS) LST is the most widely used satellite-based LST product due to its spatiotemporal coverage (1 km spatial and sub-daily temporal resolutions) and longevity (> 20 years). However, there is an increasing demand for LST products with finer spatial resolution (e.g., 10-250 m) over regions such as urban areas. Therefore, various methods have been proposed to produce high-resolution MODIS-like LST less than 250 m (e.g., 100 m). The purpose of this review is to provide a comprehensive overview of recent research trends and challenges for the downscaling of MODIS LST. Based on the recent literature survey for the past decade, the downscaling techniques classified into three groups-kernel-driven, fusion-based, and the combination of kernel-driven and fusion-based methods-were reviewed with their pros and cons. Then, five open issues and challenges were discussed: uncertainty in LST retrievals, low thermal contrast, the nonlinearity of LST temporal change, cloud contamination, and model generalization. Future research directions of LST downscaling were finally provided.