• Title/Summary/Keyword: Urban climate

검색결과 906건 처리시간 0.035초

포항시의 집합 주거공간에 있어서 외장재 및 도로 구성재료가 인체 온열 쾌적성에 미치는 영향 (The Effect of the Materials of an Outer Wall and the Paved Street on Human Thermal Comfort in a Housing Complex in Pohang City)

  • 정창원;김경대;최영식
    • 한국산업융합학회 논문집
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    • 제4권3호
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    • pp.319-327
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    • 2001
  • The objective of this study is to clarify the effect of thermal radiation environments on human thermal comfort, depending on different canyon types and surface materials on the human thermal comfort in a housing complex in Pohang city, Korea. For this purpose, the operative temperature and new effective temperature were calculated based on the modified mean radiant temperature of canyon models variated by the existence of direct radiation existence, surface materials, and the width and length of the street spaces in a housing complex. These indices for the canyon have been calculated from the meteorological data of Pohang city, which include air temperature, relative humidity, air velocity, global solar radiation and cloud. And the monthly averages of these climate factors measured at noon have been used. The results are as follows: (1) It is revealed that the short-wave radiosity reached the human body is affected by direct solar radiation and surface materials, and the long-wave radiosity by canyon types. (2) The existence of direct solar radiation, the kinds of surface materials and canyon types affect operative temperature($OT_n$) and new effective temperature($ET^*{_n}$). (3) The analysis of the human heat balance in the canyon indicates that the influence of radiation on human body is marc likely to be affected by the existence of direct solar radiation on human model.

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SWMM을 이용한 도시화유역 불투수율 변화에 따른 강우유출특성 분석 (Analysis of Rainfall-Runoff Characteristics on Impervious Cover Changes using SWMM in an Urbanized Watershed)

  • 오동근;정세웅;류인구;강문성
    • 한국물환경학회지
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    • 제26권1호
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    • pp.61-70
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    • 2010
  • The increase of impervious cover (IC) in a watershed is known as an important factor causing alteration of water cycle, deterioration of water quality and biological communities of urban streams. The study objective was to assess the impact of IC changes on the surface runoff characteristics of Kap Stream basin located in Geum river basin (Korea) using the Storm Water Management Model (SWMM). SWMM was calibrated and verified using the flow data observed at outlet of the watershed with 8 days interval in 2007 and 2008. According to the analysis of Landsat satellite imagery data every 5 years from 1975 to 2000, the IC of the watershed has linearly increased from 4.9% to 10.5% during last 25 years. The validated model was applied to simulate the runoff flow rates from the watershed with different IC rates every five years using the climate forcing data of 2007 and 2008. The simulation results indicated that the increase of IC area in the watershed has resulted in the increase of peak runoff and reduction of travel time during flood events. The flood flow ($Q_{95}$) and normal flow ($Q_{180}$) rates of Kap Stream increased with the IC rate. However, the low flow ($Q_{275}$) and drought flow ($Q_{355}$) rates showed no significant difference. Thus the subsurface flow simulation algorithm of the model needs to be revisited for better assessment of the impact of impervious cover on the long-term runoff process.

우리나라의 기온상승-도시효과인가 지구온난화인가 (Urbanization Effect on the Observed Warming in Korea during the Recent Half Century)

  • 윤진일
    • 한국농림기상학회지
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    • 제4권1호
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    • pp.58-63
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    • 2002
  • 1951-1980 평년기온 대비 1971-2000 평년기온 상승을 남한지역 14개 관측소 소재 시군의 1966년 대비 1990년의 인구증가 자연대수값에 회귀시켜 통계적으로 유의한 관계식을 얻었다. 이 관계식을 이용하여 도시화에 따른 승온효과를 제거할 경우, 순수한 지구 온난화 효과는 12월부터 4월 사이의 한후기에만 인정되며, 나머지 계절에는 나타나지 않았다. 남한지역의 한후기 일평균기온은 지구온난화에 의해 최대 0.6$^{\circ}C$까지 상승하였으며 일최저기온보다 일최고기온 상승폭이 컸다. 도시화에 따른 승온효과는 최대 0.3$^{\circ}C$에서 0.5$^{\circ}C$로 연 중(4월 제외) 고르게 나타났지만, 주로 일최저기온의 상승을 주도하였고 일최고기온 상승에는 거의 영향이 없었다.

식생캐노피모델을 통한 저관리 조방형 옥상녹화시스템의 열해석 전산모의에 관한 연구 (A study on thermal simulation for extensive green roof system using a plant canopy model)

  • 김태한
    • 한국환경복원기술학회지
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    • 제15권2호
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    • pp.137-147
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    • 2012
  • GRS is an effective urban ecology restoration technique that can manage a variety of environmental functions such as ecological restoration, rainwater spill control and island heat effect from a low-impact development standpoint that can be utilized in new construction and retrofits. Recently, quantitative evaluation studies, both domestic and abroad, in the areas related to these functions, including near-earth surface climate phenomenon, heavy rainwater regulation, thermal environment of buildings, have been actively underway, and there is a trend to standardize in the form of technological standards. In particular, centered on the advanced European countries, studies of standardizing the specific insulation capability of buildings with green system that comprehensively includes the green roof, from the perspective of replacing the exterior materials of existing buildings, are in progress. The limitation of related studies in the difficulties associated with deriving results that reflect material characteristics of continuously evolving systems due in part to not having sufficiently considered the main components of green system, mechanisms of vegetation, soils. This study attempts to derive, through EnergyPlus, the effects that the vegetation-related indicators such as vegetation height, FCV, etc. have on building energy load, by interpreting vegetation and soil mechanisms through plant canopy model and using an ecological standard indicator LAI that represent the condition of plant growth. Through this, the interpretations that assume green roof system as simple heat insulation will be complemented and a more practical building energy performance evaluation method that reflects numerical methods for heat fluxes phenomena that occur between ecology restoration systems comprised of plants and soil and the ambient space.

도시 수변공간 재생을 위한 정책 사례연구 -한강변 관리 기본계획과 런던 템즈 게이트웨이 광역 재생사업을 중심으로- (Policy case study for urban waterfront regeneration -Focused on Han River management foundation plan and London Thames gateway regeneration project-)

  • 홍순재;김승인
    • 디지털융복합연구
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    • 제14권8호
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    • pp.479-485
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    • 2016
  • 2007년에 시행된 런던 템즈 게이트웨이 광역 재생사업은 런던동부 켄트 에섹스로 연결된 템즈강 하류 구역을 배경으로 기후변화 인구밀도 주거문제 녹지조성 지역 불균형 교통문제 등을 해결하기 위해 추진한 사업이다. 사업 운영에 있어서 총 16개의 사업지구 분할과 시행기관선정으로 자치성 부여와 지자체 연계를 충실히 수행하였으며, 개발과 보존의 가치를 균형 있게 추진한 성공적인 수변공간 재생사례로 평가된다. 본 연구는 자연성 토지이용 접근성 도시경관을 골자로 한 2015년 한강변 관리 기본계획과 런던 템즈 게이트웨이 광역 재생 사업을 비교하여 다음의 결론을 도출하였다. 첫째, 현 서울시 계획안이 서울의 문제를 포괄적으로 인식하는 확산적 사고로의 검토가 필요하다. 둘째, 한강과 인접하는 지자체 및 중앙정부와의 포괄적 운영방안의 제시가 필요하다. 셋째, 수변공간을 적극적으로 활용하는 운송수단의 제시를 통해 서울의 교통문제 개선에 대한 대책마련이 필요하다.

빅데이터를 활용한 지방정부 재난안전 거버넌스 -서울시를 중심으로- (The Study on Local Government's Disaster Safety Governance using Big Data)

  • 김영미
    • 디지털융복합연구
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    • 제15권1호
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    • pp.61-67
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    • 2017
  • 시민의 안전을 위협하는 재난 재해 테러 등과 같은 긴급 상황이 발생할 경우 신속 하고 효과적인 재난안전관리체계가 구축 운영되기 위해서는 이에 맞는 적절한 대응이 필요하다. 각 재난관리 및 대응에 관련된 중앙부처뿐만 아니라 지방자치단체, 시민단체, 개인 등 모두가 상호 명확한 역할분담 하에 신속하게 대응하고 복구를 위한 통합업무 수행체계가 이행되어야 할 것이다. 서울시의 경우 기후변화에 따른 자연재난의 증가 가능성과, 테러위협의 확대, 도심의 노후화 및 산업고도화에 의한 대형재난 발생 위험성이 점점 높아지고 있어 재난 예방과 대응을 위한 효과적인 재난관리체계 구축이 시급한 실정이다. 본 연구에서는 거버넌스 관점을 적용하여 서울시의 부처간 조직체계 및 실행과정, 대응단계의 체계화를 중심으로 재난 대응체계와 재난현장에서의 지휘체계 등의 대응방안을 모색하였다.

Corporate Social Responsibility and the Pricing of Seasoned Equity Offerings: Does Executive Firm-Related Wealth Matter?

  • PHAM, Hong Chuong;NGO, Duc Anh;LE, Ha Thanh;NGUYEN, Thiet Thanh
    • The Journal of Asian Finance, Economics and Business
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    • 제7권8호
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    • pp.297-308
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    • 2020
  • This study exemines the roles of corporate social activity (CSR) and executive compensation structure on the pricing of seasoned equity offerings (SEOs) with special focus on the role of CSR in reducing the level of information asymmetry between managers and future shareholders of issuing firms through SEOs. This study also investigates the interaction between executive compensation structure and CSR on the discounting of SEOs. We use a sample of 2,102 seasoned equity offerings of U.S. firms with CSR scores from 1995 to 2015 in our OLS fixed effect regression analysis. The results show that issuing firms with high CSR are more likely to expericence a lower degree of the SEO discount. The results also document a positive association between CSR and a high proportion of equity-based compensation of issuing firms' executives. The findings of this paper confirm that CSR attenuates the impact of information asymmetry and the pre-SEO price uncertainty on the pricing of the offers and hence the SEO discount. Furthermore, CSR reinforces the impact of executive firm-related wealth on the discounting of seasoned equity offerings. It appears that firm-related wealth motivates managers to actively engage in reducing information asymmetry activities before SEOs, thereby decreasing the SEO discount.

우리나라 지역별 기온변화 특성 (A Study on the Air Temperature Changes and Regional Characteristics in South Korea)

  • 김태룡
    • 통합자연과학논문집
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    • 제2권2호
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    • pp.131-167
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    • 2009
  • Global warming is regarded as one of the most critical issues that should be taken care of by the entire global community as it threatens the survival of mankind. South Korea, in particular, undergoes faster warming than the average rate of global warming. South Korea has revealed various warming rates and trends being surrounded by sea on three sides and having complex terrains dominated by mountains. The rates vary according to regions and their urbanization and industrialization. Differences also derive from seasons and weather elements. Changes to the highest, mean, and lowest temperature are also different according to the characteristics of regions and observatories, which is more apparent where the force of artificial weather applies. In an urban area, temperature gaps tend to decrease as the lowest temperature rises more than the highest temperature. Meanwhile, temperature gaps grow further in a coastal or country region where the force of artificial weather is small and the force of natural weather prevails. In this study, the investigator analyzed the changes to the weather elements of 11 observation spots that had gone through no changes in terms of observation environment since 1961, were consecutively observed, and had the quality of their observation data monitored on an ongoing basis. Using the results, I tried to identify natural and artificial causes affecting certain spots. Located on the east coast of the Asian Continent, South Korea sees weather changing very dynamically. Having huge influences on our weather, China has achieved very rapid industrialization for the last 30 years and produced more and more greenhouse gases and air pollution due to large-size development projects. All those phenomena affect our weather system in significant ways. Global warming continues due to various reasons with regional change differences. Thus the analysis results of the study will hopefully serve as basic data of weather statistics with which to set up countermeasures against climate changes.

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하수터널의 콘크리트 라이닝 부식 방지공법 선정방법에 관한 고찰 (Selection of concrete lining corrosion protection method for large sewer tunnels)

  • 문준식;이성준
    • 한국터널지하공간학회 논문집
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    • 제16권4호
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    • pp.347-360
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    • 2014
  • 최근 기후변화로 인한 도시침수와 합류식 하수관거 월류수 (combined sewer overflow)로부터 처리되지 않은 하수의 하천유입, 그리고 그에 따른 하천의 오염의 방지를 위해 지하방수로/저류조 겸용의 대형 하수터널의 건설이 증가하고 있다. 이러한 대형 하수터널의 경우 대부분 콘크리트 라이닝을 적용하고 있지만 하수관거 내에서 발생되는 황화수소($H_2S$)로 인하여 콘크리트가 부식될 수 있으므로 이에 대한 적절한 보호공이 필요하다. 본 논문에서는 최소 100년의 수명을 고려하여 설계된 대형 하수터널의 콘크리트라이닝 부식을 방지하기 위해 여러 공법들을 소개하고 각 공법의 일반적인 장단점과 설계 사례를 설명하였다. 하지만 대형 하수터널 라이닝의 부식방지 공법들의 적용 실적이 부족하여 부식방지 공법을 적용한 터널설계 대안에 대한 객관적인 평가가 쉽지 않다. 따라서 본 논문은 설계 사례연구를 통해 콘크리트 라이닝 부식방지 공법선정 프로세스를 소개하였다.

Ground surface changes detection using interferometric synthetic aperture radar

  • Foong, Loke Kok;Jamali, Ali;Lyu, Zongjie
    • Smart Structures and Systems
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    • 제26권3호
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    • pp.277-290
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    • 2020
  • Disasters, including earthquakes and landslides, have enormous economic and social losses besides their impact on environmental disruption. Iran, and particularly its Western part, is known as an earthquake susceptible area due to numerous strong ground motions. Studying ecological changes due to climate change can improve the public and expert sector's awareness and response to future disastrous events. Synthetic Aperture Radar (SAR) data and Interferometric Synthetic Aperture Radar (InSAR) technologies are appropriate tools for modeling and surface deformation modeling. This paper proposes an efficient approach to detect ground deformation changes using Sentinel-1A. The focal point of this research is to map the ground surface deformation modeling is presented using InSAR technology over Sarpol-e Zahab on 25th November 2018 as a study case. For surface deformation modeling and detection of the ground movement due to earthquake SARPROZ in MATLAB programming language is used and discussed. Results show that there is a general ground movement due to the Sarpol-e Zahab earthquake between -7 millimeter to +18 millimeter in the study area. This research verified previous researches on the advanced image analysis techniques employed for mapping ground movement, where InSAR provides a reliable tool for assisting engineers and the decision-maker in choosing proper policies in a time of disasters. Based on the result, 574 out of 682 damaged buildings and infrastructures due to the 2017 Sarpol-e Zahab earthquake have moved from -2 to +17 mm due to the 2018 earthquake with a magnitude of 6.3 Richter. Results show that mountainous areas have suffered land subsidence, where urban areas had land uplift.