• Wind and Structures
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• 제22권1호
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• pp.89-106
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• 2016

With an aim to assess the wind damage to urban trees in more realistic conditions, the nonlinear dynamics of structured trees subjected to strong winds with different levels is investigated in the present paper. For the logical treatment of dynamical behavior of trees, material nonlinearities of green wood associated with tree biomechanics and geometric nonlinearity of tree configuration are included. Applying simulated fluctuating wind velocity to the numerical model, the dynamical behavior of the structured tree is explored. A comparative study against the linear dynamics analysis usually involved in the previous researches is carried out. The failure wind velocity of urban trees is then defined, whereby the failure percentages of the tree components are exposed. Numerical investigations reveal that the nonlinear dynamics analysis of urban trees results in a more accurate solution of wind-induced response than the classical linear dynamics analysis, where the nonlinear effect of the tree behavior gives rise to be strengthened as increasing of the levels of wind velocity, i.e., the amplitude of 10-min mean wind velocity. The study of relationship between the failure percentage and the failure wind velocity provides a new perspective towards the vulnerability assessment of urban trees likely to fail due to wind actions, which is potential to link with the practical engineering.

• 한국도로학회논문집
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• 제16권3호
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• pp.21-33
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• 2014

PURPOSES : This study presents a specific methodology for air dispersion analysis of urban areas methodology in accordance with urban planning and transport policy. METHODS : This study performed three alternatives including development density and public transit applying integrated urban model for the Delft city on Netherlands. Based on this result, the two types of air pollutant emissions($PM_{10}$, NOx) were calculated and analyzed the emission dispersion on that City. RESULTS : As a result, the quality of air near the City is better than that of current conditions showed that approximately from 2.1 to 7.9% according to alternatives. CONCLUSIONS : Air quality assessment in urban areas can be reasonably performed by applying a methodology when urban development and transport policy are considered.

• 한국수자원학회논문집
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• 제36권5호
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• pp.725-740
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• 2003

도시화에 따라 인구집중과 광역화로 인하여 자연환경이 크게 변화하였으며, 특히 인간의 활동은 새로운 유출양상을 가져오는 원인이 되었다. 본 연구에서는 도시의 개발에 따른 도시화 전$\cdot$후의 지형인자가 변화함으로써 야기되는 유출변화 특성을 해석하였다. 도시화유역에서의 유출에 ILLUDAS 모형을 이용하였으며, 다음과 같은 결론을 얻었다. 도시화 전$\cdot$후의 첨두발생시간을 살펴보면, 약 15∼35 분 정도 단축되었으며, 도시화 후의 첨두홍수량은 최대 60 % 정도 증가함을 알 수 있었다.

• 한국환경복원기술학회지
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• 제21권2호
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• pp.53-64
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• 2018

This study aims to quantitatively evaluate the conservation priorities of unexecuted urban parks in Seoul both from an ecological and public perspective. To this end, two methodologies, ecological network analysis based on graph and circuit theory and accessibility analysis, were employed in order to assess ecological connectivity of and public accessibility to unexecuted parks, respectively. This study applied linkage-mapping methods (shortest path and current flow betweenness centrality) of connectivity analysis to an integrated map of landscape permeability. The population-weighted accessibility to unexecuted parks was measured based on a negative exponential distance decay function. As a result, for both ecological connectivity and accessibility, Gwanaksan, Suraksan, and Bulamsan urban natural parks are found to be the most important (rank 1-3) to be conserved. For these sites, inner park areas with conservation priorities for connectivity and accessibility were identified. The findings of the study can be used for giving conservation priority to the unexecuted urban parks in terms of long-term sustainable urban planning.

• 한국환경복원기술학회지
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• 제21권1호
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• pp.73-82
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• 2018

Urban parks are important bird habitat in cities. Various studies have evaluated the habitat function of urban parks focused on field surveys. In this study, we performed applicability of NDVI obtained from Landsat 8 OLI image as a factor for spatial planning considered bird diversity. This study was classified with green boundary into three groups using NDVI's value. Environmental variables were calculated by the green area ratio of the surrounding area from 100m to 500m at each groups. The 20 environmental variables such as park area, park shape index, canopy of tree, etc. were derived, the regression analysis was performed as a dependent variable for the bird diversity of urban parks. As a result, the park area and the green area ratio of Group 3, classified high NDVI, within the 100m buffer were adopted as the variables in the regression model. In other words, it was confirmed that as the park becomes larger, the distribution of key green areas within a radius of 100m of the parks becomes higher, the diversity of bird species has increased. It was appropriate to use satellite image, NDVI to analyze species diversity in urban area.

• KIEAE Journal
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• 제14권3호
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• pp.15-21
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• 2014

In this study, we developed a modular rainwater infiltration system that can be applied for general purposes in urban areas to prepare for localized heavy rain caused by climatic change. This study also analyzed the system's effects on reducing runoff. An analysis of the system's effects on reducing runoff based on rainfall data and monitoring data obtained between September 2012 and December 2013 after the system was installed showed that approximately 20~22% of the runoff overflowed from the infiltration facility. Also, an analysis of the runoff that occurred during the monsoon season showed that 25% of the runoff overflowed through the storm sewer system of the urban area. These results show that the rainwater overflows after infiltrating the detention facility installed in the area during high-intensity rainfall of 100mm or higher or when precipitation is 100mm for 3~4 days without the prior rainfall. According to precipitation forecasts, torrential rainfall is becoming increasingly prevalent in Korea which is increasing the risk of floods. Therefore, the standards for storm sewer systems should be raised when planning and redeveloping urban areas, and not only should centralized facilities including sewer systems and rainwater pump facilities be increased, but a comprehensive plan should also be established for the water cycle of urban areas. This study indicates that decentralized rainwater management can be effective in an urban area and also indicates that the extended application of rainwater infiltration systems can offer eco-friendly urban development.

• 한국조경학회지
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• 제26권3호
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• pp.134-142
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• 1998

THe purpose of this study is to suggest the major determinants of visual preference in the outdoor spaces of urban office buildings. For this, the spatial image was analyzed by the factor analysis algorithm. The level of visual preferences was measured by a slide simulation test, and these data were analyzed by the multiple regressioni. The result of this study can be summarized as follows; Factors covering the spatial image were found to be 'mystery','changeability','coherence' and 'legibility'. T.V. was obtained as 58.4%. Outdoor spaces of urban office buildings were classified into four groups by the multi dimensional scaling method. As for the analysis of imageability in each spatial type, the factor scores of measuring high values were different for all types. Type II, IV obtained higher rank of visual preference and type III, I obtained lower. For all types, the factors of visual preference were found to be 'mystery','changeability','coherence' and 'legibility'. The visual preference determinants of urban setting focused on outdoor spaces of urban office buildings may be the major factors which must be considered in planning and designing as the functional basis for the quantitative analysis.

• 한국환경복원기술학회지
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• 제23권6호
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• pp.125-135
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• 2020

The uncontrolled urban expansion causes various social, economic problems and natural/environmental problems. Therefore, it is necessary to forecast urban expansion by identifying various factors related to urban expansion. This study aims to forecast it using a decision tree that is widely used in various areas. The study used geographic data such as the area of use, geographical data like elevation and slope, the environmental conservation value assessment map, and population density data for 2006 and 2018. It extracted the new urban expansion areas by comparing the residential, industrial, and commercial zones of the zoning in 2006 and 2018 and derived a decision tree using the 2006 data as independent variables. It is intended to forecast urban expansion in 2030 by applying the data for 2018 to the derived decision tree. The analysis result confirmed that the distance from the green area, the elevation, the grade of the environmental conservation value assessment map, and the distance from the industrial area were important factors in forecasting the urban area expansion. The AUC of 0.95051 showed excellent explanatory power in the ROC analysis performed to verify the accuracy. However, the forecast of the urban area expansion for 2018 using the decision tree was 15,459.98㎢, which was significantly different from the actual urban area of 4,144.93㎢ for 2018. Since many regions use decision tree to forecast urban expansion, they can be useful for identifying which factors affect urban expansion, although they are not suitable for forecasting the expansion of urban region in detail. Identifying such important factors for urban expansion is expected to provide information that can be used in future land, urban, and environmental planning.

• 한국지역지리학회지
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• 제3권2호
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• pp.227-253
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• 1997

21C는 문화 예술의 시대가 될 것임을 예고하고 있다. 따라서 전통적으로 지역을 연구해 온 지리학은 지역 문화에 대한 심층적 연구를 필요로 하게 되었다. 지역 문화를 밝힐 수 있는 중요한 것 중의 하나가 지역의 상징이다. 오늘날 지구 도시의 출현과 더불어 특히 도시 문화에 대한 연구는 시대적 요청이 되고 있다. 도시 문화를 도시의 상징 즉 한국 각 도시가 제정하고 있는 상징 노래(시가(市歌)), 상징새(시조(市鳥)), 상짐꽃(시화(市花)), 상징 나무(시목(市木))를 통해 분석하여 도시 상징의 공간 환경을 밝혀 보고자 한다. 한국 도시의 상징 노래를 분석해 보면 노래가사 속에는 공간 환경 요소를 포함하고 있는데, 그 중 지형 주로 산과 강의 명칭 그리고 해당 지역의 지명은 거의 모든 노래 가사 속에서 나타나고 있다. 이러한 공간 환경 요소들은 특정 도시의 정체성을 나타내 주며, 그 시민들의 통합성과 일체감을 불러일으키는 상징적 공간으로 볼 수 있다. 특히, 산 및 강과 관련된 지명은 국토의 70%가 산지지형인 우리나라에서는 풍수의 기본 요소로서 산 및 물과 관련된 상징적 공간으로 볼 수 있다. 지명 또한 그 지역의 이미지를 잘 나타내는 상징적 공간이 핀다. 한국 도시의 상징물 즉 상징새, 상징 나무, 상징꽃 분석을 통해 한국 도시의 상징물은 중복 제정이 많다. 특히 상위 계층의 상징물이 하위 계층에서 중복 제정되었다는 점이다. 이러한 상징물들은 우리 민족의 삶을 통해 내려온 상징의 공간 환경으로 볼 수 있으나, 해당 도시의 기후, 토양 등 공간 환경적 특성과 상관없이 중복 제정된 점과 정체성이 없는 외래종이 많은 점은 시대적으로 상징물을 재검토해야 할 필요성이 있다. 가장 지방적인 것이 가장 지구적인 것이 되어야 할 시대에 우리의 기후, 토양, 문화적 특성에 맞는 도시의 상징물을 정할 것이 요망된다.

• 한국농촌건축학회논문집
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• 제24권4호
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• pp.1-8
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• 2022

This study aims to investigate the gap in accessibility to urban planning facilities between living spheres in local small and medium-sized cities. In this study, OD data between administrative dongs of public transportation users was constructed to analyze the living shpere, and community analysis was conducted based on cohesion between data. As a result of the analysis, it was confirmed that a total of 10 clusters (mid-living areas) were formed, and the topographical difference between the 11 middle living areas established in the existing Jinju City Basic Plan and the single living areas were actively exchanged to form a community with other administrative dongs. Next, the analysis of the service area of urban planning facilities for mid-living areas was conducted based on the road network. As a result of analyzing the area accessible within 5, 10, and 15 minutes, educational facilities, public facilities, cultural facilities, tourism, and green facilities could be reached within 15 minutes in most mid-living areas. On the other hand, there were many areas where access to transportation facilities, medical facilities, and cultural facilities was difficult within 15 minutes. In particular, the accessibility of the outer living area and the central living area were different. To improve the quality of life of citizens, using urban planning facilities in Jinju-si and establishing related plans in urban basic plans, it is necessary to conduct a study on service areas through network analysis.