• Title/Summary/Keyword: Urban Image

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A Study on Utilizing 1:1,000 Digital Topographic Data for Urban Landuse Classification (도시지역 토지이용분류를 위한 1:1,000 수치지형도 활용에 관한 연구)

  • Min, Sookjoo;Kim, Kyehyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.1D
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    • pp.149-156
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    • 2006
  • Existing method of landuse classification using aerial photographs or field survey requires relatively higher amount of time and cost due to necessary manual work. Especially in urban area where the pattern of landuse is densely aggregated, a landuse classification using satellite image is more complex. In this background, this study proposes a landuse classification method to utilize 1:1,000 digital topographic data and IKONOS satellite image. To prove the possibility of this method, the method was applied to Seoul metropolitan area. The results shows the total accuracy of approximately 95% and 14 landuse classes extracted. Based on the results from the pilot study, this method is applicable to landuse classification in urban area.

A Study on the Correlation between Spatial Distance and Cognitive Intensity of High-rise Buildings - Focusing on High-rise Buildings of More than 30 Stories in Seoul - (초고층 랜드마크의 공간적 거리 및 인지강도와의 상관성 분석 - 서울시 30층 이상 고층건물을 대상으로 -)

  • Byeon, Jae-Sang;Im, Seung-Bin;Joo, Shin-Ha
    • Journal of the Korean Institute of Landscape Architecture
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    • v.35 no.4
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    • pp.90-104
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    • 2007
  • Landmarks like high-rise building are one of the important elements for the enhancement of city identity and provides the hierarchy of city streets, playing a central and symbolic role in cities. Research on physical attribute of landmarks, such as height, distance, location and shape, which are suitable for a city scale, can help a city create a distinct image and maintain comprehensible structure. To achieve this purpose, it is necessary to understand the spatial and cognitive characteristics of a landmark for the establishment and management of it. The results of this study can be summarized as follows: 1. The level of representativeness of a landmark increases in proportion to the degree of cognitive intensity on it. The relation between representativeness and cognitive intensity can be explained as the log-function as follows: Log(the number of people who respond "It has representativeness")=$-1.2579+1.5908{\times}$(cognitive intensity); 2. There are a few differences based on the attributes of respondents: while gender has no distinct influence, residential period and age show statistically meaningful influence on cognitive intensity of a vertical landmark Cognitive intensity of an individual landmarks especially, differs according to the class of main users. Because of frequent changes in occupation or employment, respondents consider the distance from a residential area more important than the distance from a working area in evaluating cognitive intensity of landmarks; 3. landmark can be classified into two kinds: a district landmark and an urban landmark A district landmark is closely connected with physical attributes of the landmark itself, such as distance, size and height. An urban landmark is mainly related to cognitive attributes such as the image and identity of a city as a whole. As a result, the landmark analysis data in this research provides spatial order and identity in a city. It is difficult to establish and reinforce the image of a city as a single element ike a landmark. However, withy steady follow-up research, this study could be seen as a systematic and logical model to improve urban landscape and image.

Visual Impact Factor and Preference Image of Urban Stream Landscape (도시 소하천 경관의 시각적 선호 이미지와 영향요인)

  • Kim, Dae-Hyun;Kim, Dae-Soo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.2 no.4
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    • pp.9-15
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    • 1999
  • The purpose of this study was to investigate factors and variables which have significant effects on visual preference of urban stream in Taejon city and to suggest design & management information for urban stream. These works consist of two phases. First, we tested the Hyechon college students' visual preference for 36 spots of urban stream slide and then selected 10 spots slide by the Sturges' formula. Second, we analyzed factors and variables of visual preference of urban stream using the semantic differential scale method and then processed using descriptive analysis, factor analysis and multiple linear regression analysis. The major findings of this study can be summarized as follows. 1. The difference of landscape adjectives between the highest score of visual preference slide (No.10) and the lowest score of visual preference slide (No.2) was cleanness. 2. Three factors, the nature, the cleanness and the movement, were derived from the factor analysis. 3. Factors covering the visual preference of urban stream have been found to be the landscape of urban stream, the nature, the cleanness, and the movement. The visual preference factors of urban stream need to be considered in creating or restoring the ecological urban stream landscape.

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Building Change Detection Methodology in Urban Area from Single Satellite Image (단일위성영상 기반 도심지 건물변화탐지 방안)

  • Seunghee Kim;Taejung Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.5_4
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    • pp.1097-1109
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    • 2023
  • Urban is an area where small-scale changes to individual buildings occur frequently. An existing urban building database requires periodic updating to increase its usability. However, there are limitations in data collection for building changes over a wide urban. In this study, we check the possibility of detecting building changes and updating a building database by using satellite images that can capture a wide urban region by a single image. For this purpose, building areas in a satellite image are first extracted by projecting 3D coordinates of building corners available in a building database onto the image. Building areas are then divided into roof and facade areas. By comparing textures of the roof areas projected, building changes such as height change or building removal can be detected. New height values are estimated by adjusting building heights until projected roofs align to actual roofs observed in the image. If the projected image appeared in the image while no building is observed, it corresponds to a demolished building. By checking buildings in the original image whose roofs and facades areas are not projected, new buildings are identified. Based on these results, the building database is updated by the three categories of height update, building deletion, or new building creation. This method was tested with a KOMPSAT-3A image over Incheon Metropolitan City and Incheon building database available in public. Building change detection and building database update was carried out. Updated building corners were then projected to another KOMPSAT-3 image. It was confirmed that building areas projected by updated building information agreed with actual buildings in the image very well. Through this study, the possibility of semi-automatic building change detection and building database update based on single satellite image was confirmed. In the future, follow-up research is needed on technology to enhance computational automation of the proposed method.

PPK GNSS System based UAV Photogrammetry for Construction of Urban Disaster Prevention Information (도시방재정보 구축을 위한 PPK GNSS 기반의 무인항공사진측량)

  • Park, Joon Kyu;Kim, Min Gyu
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.4
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    • pp.355-362
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    • 2017
  • Recently, UAV(Unmanned Aerial Vehicle) have been utilized in various fields, including surveys, mapping, and spatial analysis, depending on the increase in demand for spatial information and UAV is receiving a lot of attention due to rapid data acquisition and economic viability. In this study, the applicability of UAV image images was analyzed for urban disaster prevention. UAV images were acquired for the study area and digital surface model and ortho image were generated through data processing. Also, the process using PPK(Post Processed Kinematic) GNSS method is compared with existing method. Through the research, it was able to effectively deploy urban disaster prevention information about the target area, and displayed the effectiveness of the methods for efficient comparison with existing unmanned aerial photogrammetry. If the PPK technique is applied to thethe disaster prevention field, it is expected that the work flow in the field of rapid data acquisition and disaster prevention data construction can be greatly improved.

Land Use Feature Extraction and Sprawl Development Prediction from Quickbird Satellite Imagery Using Dempster-Shafer and Land Transformation Model

  • Saharkhiz, Maryam Adel;Pradhan, Biswajeet;Rizeei, Hossein Mojaddadi;Jung, Hyung-Sup
    • Korean Journal of Remote Sensing
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    • v.36 no.1
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    • pp.15-27
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    • 2020
  • Accurate knowledge of land use/land cover (LULC) features and their relative changes over upon the time are essential for sustainable urban management. Urban sprawl growth has been always also a worldwide concern that needs to carefully monitor particularly in a developing country where unplanned building constriction has been expanding at a high rate. Recently, remotely sensed imageries with a very high spatial/spectral resolution and state of the art machine learning approaches sent the urban classification and growth monitoring to a higher level. In this research, we classified the Quickbird satellite imagery by object-based image analysis of Dempster-Shafer (OBIA-DS) for the years of 2002 and 2015 at Karbala-Iraq. The real LULC changes including, residential sprawl expansion, amongst these years, were identified via change detection procedure. In accordance with extracted features of LULC and detected trend of urban pattern, the future LULC dynamic was simulated by using land transformation model (LTM) in geospatial information system (GIS) platform. Both classification and prediction stages were successfully validated using ground control points (GCPs) through accuracy assessment metric of Kappa coefficient that indicated 0.87 and 0.91 for 2002 and 2015 classification as well as 0.79 for prediction part. Detail results revealed a substantial growth in building over fifteen years that mostly replaced by agriculture and orchard field. The prediction scenario of LULC sprawl development for 2030 revealed a substantial decline in green and agriculture land as well as an extensive increment in build-up area especially at the countryside of the city without following the residential pattern standard. The proposed method helps urban decision-makers to identify the detail temporal-spatial growth pattern of highly populated cities like Karbala. Additionally, the results of this study can be considered as a probable future map in order to design enough future social services and amenities for the local inhabitants.

Analysis of Heat Island Characteristics Considering Urban Space at Nighttime (도시공간을 고려한 야간시간대의 열섬특성 분석)

  • Song, Bong-Geun;Park, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.1
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    • pp.133-143
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    • 2012
  • The purpose of this study is to investigate the characteristics of urban heat island considering urban space at nighttime. We used to analyze landuse and landcover data of 1:1,000 scale, DTM, and surface temperature extracted ASTER image satellite of nighttime. According to the analytical results, heat intensity in single-family residential is higher than that in industrial area, public facility area, and commercial area because the anthropogenic heat by energy consumption is released. Likewise, the temperature difference were big in the buildings of industrial area depending on operating hours. Meanwhile, green and river area had cooling impacts mitigating the urban heat island. Therefore, we have to mitigate heat intensity through constructing green space and waterfront area. As mentioned above, we think that the results of this study will be used as base data for effective spatial planning when formulating development planning to mitigate urban heat island at nighttime.

Estimation of Storage Capacity using Topographical Shape of Sand-bar and High Resolution Image in Urban Stream (도시하천의 지형태 자료와 영상정보를 이용한 수체적 시험평가)

  • Lee, Hyun Seok;Lee, Geun Sang
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.3D
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    • pp.445-450
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    • 2008
  • Recently, environmental and ecological approaches is in progress in urban stream, especially the guarantee of instream flow becomes very important. In this paper, it is suggested that water volume estimation method utilizing the topographical shape data obtained by field investigation and satellite image to manage the urban stream efficiently. The data obtained at Gap River is the study area are analysed and those results are as belows. First, surveying to investigate topographic shape characteristics of urban stream is carried out. In details, the gradient characteristics from water surface to bottom in case of sand area and in case of grass area are 0.013 and 0.065 respectively. In conclusion, the gradient characteristic of grass area is five times bigger than that of sand area. Besides, IKONOS image is classified by spectrum analysis and Minimum Distance Method and the sand area extraction method by the generalization method as Median filter is suggested to calculate water volume. Finally, mapping process on the sand area extracted from the topographical shape field data in river and satellite images is carried out by the GIS spatial analysis. And on the assumption that the water level was 1m at that time when satellite image was taken, the water volume was $225,258m^3$. It is clarified that the effect of water volume improvement was about 10.5% in comparison with water volume that had no consideration on the gradient characteristics of sand-bar.

A Study on Preference Characteristics and Evaluation Factors of View by Layout Types of Apartment Houses (공동주택 배치유형별 경관 선호특성과 평가요인에 관한 연구)

  • Bong, Jong-Jin;Park, Hyang-Yong;Jeong, Hak-Gyun;Yoo, Chang-Geun;Cho, Yong-Joon
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2004.11a
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    • pp.239-244
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    • 2004
  • Large-scaled apartment housing complex at outskirts of downtown which has direct influence on urban view concentrated on improving the space outside the complex like spatial composition of individual plan design, but neglected the contribution of urban view. However, as people's orientation toward urban areas was changed to quality from quantity, concerns on urban view have been gradually increased and planning of apartment housing has been extended to complex with view contributing to urban people as a factor composing the city in resident centered spatial composition. This study is therefore to examine the characteristics of view components of 13 apartment housing complexes at Sangmu District in Gwangju Metropolitan City and their influences on evaluating view image.

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The 3rd National Conference Of Professional engineers - Urban Public Design & Convergence City for City Competitiveness (제3회 전국기술사대회 특집(3차분) - 도시경쟁력을 위한 도시공간 디자인과 컨버전스 도시 - 도시계획 -)

  • Suh, Jeong-Yeal
    • Journal of the Korean Professional Engineers Association
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    • v.42 no.6
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    • pp.31-35
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    • 2009
  • This paper aims to draw out the practical lessons for City Brand as aspect of urban spatial by urban regeneration project in Korea. Image of the City and City Brand is the most important element for the competitiveness of modern cities. This paper discusses the guide line or strategy of City Brand, its current status in Korea. It also examines the present Urban Regeneration in Korea, identifies the problems encountered in implementation, and suggests the solutions for strengthening urban competitiveness such as a City Brand. Also it emphasized that well planned invisible and physical environments, including story and land-mark facilities, are also crucial in making City Brand more attractive and competitive.

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