• Title/Summary/Keyword: Urban Change

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The extraction method for the best vegetation distribution zone using satellite images in urban area

  • Jo, Myung-Hee;Kim, Sung-Jae;Lee, Kwang-Jae
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.908-910
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    • 2003
  • In this paper the extraction method for the best suitable green vegetation area in urban area, Daegu, Korea, was developed using satellite images (1994, 1999, Landsat TM). For this, the GIS overlay analysis of GVI (Green Vegetation Index), SBI (Soil Brightness index), NWI (None-Such wetness Index) was performed to estimate the best suitable green vegetation area. Also, the statistical documents, algorithm and Tasseled-Cap index were used to recognize the change of land cover such as cultivation area, urban area, and damaged area. Through the result of this study, it is possible to monitor the large sized reclamation of land by drainage or damaged area by forest fires. Moreover, information with the change of green vegetation and the status of cultivation by GVI, but also moisture content by percentage by NWI and surface class by SBI can be obtained.

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Long-term Estimation and Mitigation of Urban Development Impact on Watershed Hydrology (도시개발로 인한 장기 수문변화 예측과 저감 방안)

  • Jeon, Ji-Hong;Jang, Joo Bok;Kim, Tae-Dong;Choi, Donghyuk
    • Journal of the Korean Society of Urban Environment
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    • v.18 no.4
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    • pp.419-428
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    • 2018
  • This study is aimed at estimating and mitigating the impact of urban development on watershed hydrology for new town experienced with dramatical change of land use from rural to urban. The climate change scenario, representative concentration pathway (RCP), revealed direct response of runoff depth to precipitation, which increased until year 2100. The types of areas for urban use in addition to climate change affected the efficiencies of bioretention, applied as a low impact development (LID). Combining different areas for urban use suggested that a possible approach to mitigate the urban development impact on watershed hydrology by supplementing captured rainfall potential from area to area and attenuating peak discharge and retarding its time of concentration.

Cellular Automata Based Urban Landuse Change Modeling Considering Development Density (개발밀도를 고려한 셀룰러 오토마타 기반의 도시 토지이용 변화 모델링)

  • Cho, Dae-Heon
    • Journal of the Korean Geographical Society
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    • v.43 no.1
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    • pp.117-133
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    • 2008
  • Although development density control has received murk attention in urban planning, there has been little research on empirical methods that can examine local changes in development density. Recently, attempts have been made to develop cellular automata (CA) models that can be applied to urban landuse change. This paper aims to develop an extended landuse change model based on urban CA considering development density. The proposed model not only includes density control component in a model framework, but also directly estimates local density changes in land use. The developed model was applied to the study area, which was a part of central Seoul. The calibration of the model was carried out over the period $1900s\sim2000s$ using parcel-based land use data and related variables The results of the calibrated model have been tested by comparison with actual landuse data, and have demonstrated that the developed model can produce realistic simulations of urban landuse changes. But model output is dependent on the spacio-temporal resolution of input data. Further research is necessary to improve the calibration procedure and methods for evaluating model validity.

The Study of Landscape Fragmentation for the Urban Landscape Planning (도시경관계획수립을 위한 경관파편화에 관한 연구)

  • Jung, Sung-Gwan;Oh, Jeong-Hak;Park, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.6 no.3
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    • pp.11-20
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    • 2003
  • Many-sided approach methods are being demanded to solve environmental problems in urban areas. One of these methods will be to manage forests scattered in urban areas efficiently. This paper is to grasp the change of land use and landscape indices in Mt. Ap, Daegu, and to analyze the change of landscape structure. Mt. Ap is near Daegu Metropolitan, so under unnatural interferences of human activity persistently. The results of above analysis run as follows: First, the north of the case area is connected to forest, and keeps stable equilibrium ecologically, while the other parts of it suffer from rural exodus and side effects of urbanization which has been completed since 1980. Second, according to the area-rate change of each landscape element, a cultivated areas has been converted into urban one, especially Pinus densiflora forests and paddy fields into mixed forests and urban areas. Finally, most of plantations have been converted into deciduous forests and mixed forests in failure of adaption of plants in burned areas rather than owing to factitious interference.

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SENSITIVITY OF THE KEUM RIVER BASIN TO CLIMATE CHANGE

  • Kim, Young-Oh;Seo, Yong-Won;Lee, Seung-Hyun;Lee, Dong-Ryul
    • Water Engineering Research
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    • v.1 no.4
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    • pp.267-277
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    • 2000
  • This study reports an examination of the sensitivity of water resources in the Keum River basin to climate change. Assuming a doubling in $CO_2$ concentrations, a cooperative study provided four climate change scenarios for this study, which have been translated into temperature and precipitation scenarios on a basin scale. The study utilized these temperature and precipitation data for each climate change scenario as inputs to the NWS-PC model to generate the corresponding streamflow scenario over the Keum River basin. A reservoir simulation model for the Dae-Chung Dam in the Keum River basin has been developed with an object-oriented simulation environment, STELLA. For each streamflow scenario, the performance of the reservoir was assessed in terms of reliability, resiliency, and vulnerability. Although the simulation results are heavily dependent on the choice of the climate change scenarios, the following conclusions can be clearly concluded: (1) the future streamflow over the Dae-Chung Dam tends to decease during the dry period, which seriously increases competitive water use issues and (2) flood control issues predominate under the $2CO_2$-High case.

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A Study on Urban Change Detection Using D-DSM from Stereo Satellite Data

  • Jang, Yeong Jae;Oh, Kwan Young;Lee, Kwang Jae;Oh, Jae Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.5
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    • pp.389-395
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    • 2019
  • Unlike aerial images covering small region, satellite data show high potential to detect urban scale geospatial changes. The change detection using satellite images can be carried out using single image or stereo images. The single image approach is based on radiometric differences between two images of different times. It has limitations to detect building level changes when the significant occlusion and relief displacement appear in the images. In contrast, stereo satellite data can be used to generate DSM (Digital Surface Model) that contain information of relief-corrected objects. Therefore, they have high potential for the object change detection. Therefore, we carried out a study for the change detection over an urban area using stereo satellite data of two different times. First, the RPC correction was performed for two DSMs generation via stereo image matching. Then, D-DSM (Differential DSM) was generated by differentiating two DSMs. The D-DSM was used for the topographic change detection and the performance was checked by applying different height thresholds to D-DSM.

Object-based Building Change Detection from LiDAR Data and Digital Map Using Adaptive Overlay Threshold (적응적 중첩 임계치를 이용한 LiDAR 자료와 수치지도의 객체기반 건물변화탐지)

  • Lee, Sang-Yeop;Lee, Jeong-Ho;Han, Su-Hee;Choi, Jae-Wan;Kim, Yong-Il
    • Journal of Korean Society for Geospatial Information Science
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    • v.19 no.3
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    • pp.49-56
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    • 2011
  • Because urban areas change rapidly, it is necessary to reflect urban changes in a digital map database in a timely manner. To address these issues, LiDAR data was used to detect changes in urban area buildings. The purpose of this study is to detect object-based building change using LiDAR data and existing digital maps, and classify change types. In the study, we classified change type using overlay and shape comparison with building layer of the digital maps and point-based extracted building outline from the LiDAR data. When applying the overlay method, we were able to increase the accuracy and objectivity of the change detection process throughout an adaptive threshold applied to each object. In the experiments, it was demonstrated that classifying and detecting changes in urban areas using the proposed method can provide superior classification accuracy compared with the existing methodology.

Change Detection of Urban Development over Large Area using KOMPSAT Optical Imagery (KOMPSAT 광학영상을 이용한 광범위지역의 도시개발 변화탐지)

  • Han, Youkyung;Kim, Taeheon;Han, Soohee;Song, Jeongheon
    • Korean Journal of Remote Sensing
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    • v.33 no.6_3
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    • pp.1223-1232
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    • 2017
  • This paper presents an approach to detect changes caused by urban development over a large area using KOMPSAT optical images. In order to minimize the radiometric dissimilarities between the images acquired at different times, we apply the grid-based rough radiometric correction as a preprocessing to detect changes in a large area. To improve the accuracy of the change detection results for urban development, we mask-out non-interest areas such as water and forest regions by the use of land-cover map provided by the Ministry of Environment. The Change Vector Analysis(CVA) technique is applied to detect changes caused by urban development. To confirm the effectiveness of the proposed approach, a total of three study sites from Sejong City is constructed by combining KOMPSAT-2 images acquired on May 2007 and May 2016 and a KOMPSAT-3 image acquired on March 2014. As a result of the change detection accuracy evaluation for the study site generated from the KOMPSAT-2 image acquired on May 2007 and the KOMPSAT-3 image acquired on March 2014, the overall accuracy of change detection was about 91.00%. It is demonstrated that the proposed method is able to effectively detect urban development changes in a large area.

A Study on the Change of the Urban Heat Island Structure in Busan Metropolitan Area, Korea (부산지역의 도시열섬 구조 변화에 관한 연구)

  • Kim, Hyunsu;Seok, Hyun-Bae;Kim, Yoo-Keun
    • Journal of Environmental Science International
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    • v.23 no.11
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    • pp.1807-1820
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    • 2014
  • The spatial and temporal changes of the annual mean urban heat island(UHI) intensity were investigated using near surface temperature data measured at 16 automatic weather systems(AWS) in Busan metropolitan area(BMA) during the 11-yr period, from 2000 to 2010. For nighttime, the annual mean UHI intensity at Dongnae(U1) in 2000 was weaker than it in 2010. However the change of the annual mean UHI intensity at Daeyeon(U2) during 11 years was different from it at U1. The annual frequency of the UHI intensity over $5^{\circ}C$ considerably increased at U2 and decreased at U1 during 11 years. The center of the UHI also spatially shifted southward with Daeyeon and Haeundae in BMA. It would be caused by the increase of urban area, population-density and transportation near U2 and by the decrease of them near U1. We found that the spatial and temporal differences of the UHI intensity have coincided with changes of land-use, population density and transportation in BMA.

A Nutrition Survey of Urban Elderly in Seoul with the Analysis of Deitary Attitude after Retirement (서울시내 거주 노인의 영양섭취실태 및 식생활태도 조사연구 -은퇴한 노인을 중심으로-)

  • 강남이
    • Journal of Nutrition and Health
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    • v.19 no.1
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    • pp.52-65
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    • 1986
  • This study deals with the conditions of nutritional intake of the urban elderly (age sixty years and older). This study analysis is based on factors that are influenced on the prevalent conditions of dietary-intake of the urban elderly either it be for better ment of health or desire. The method of this research was based on the interview-survey with questinaire in the Seoul area. In comparison to the surveys taken of the rural society and the urban slum elderly the urban elderly standard nutritional requirements was higher. Of the standard nutritional requrieemtns the twomen's nutrition intake was higher than of the men. But still the problem of malnutrition existed in the urban elderly both men and women at the probability nutritional deficienty rate higher than 30%. The food intake frequency factors which might influence the condition of nutritional intake was significant more than condition of eating. Another important factors of the conditions of nutritioal intake of the urban elderly are one's self-consciousness of health and degree of one's will change . In healthy case of the aged, their will was almost maintained and hand -grip strength was high when they had regular meal with their family . For elderl with the lower academic career and the one with more satisfactory to his meal, their wills didn't change before or after retirement. The objectiveness of this survey is to convince the elderly that the problems of nutritional deficiency can only be solved by reeducation and to improve their nutritional diet to have the enjoyments of a healtheir elderly life.

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