• Title/Summary/Keyword: urban feature

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A Study on Determining Control Points and Surveying Feature Points for Geo-Referencing of Terrestrial LiDAR Data in Urban Areas (도심지 지상 LiDAR 자료의 Geo-Referencing을 위한 기준점 선정 및 특징점 측량 방안 연구)

  • Park, Hyo-Keun;Han, Soo-Hee;Cho, Hyung-Sig;Kim, Sung-Hoon;Sohn, Hong-Gyoo;Heo, Joon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.1
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    • pp.179-186
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    • 2010
  • In this research, an effective method for absolute positioning of feature points is proposed, which is applicable to geo-referencing of terrestrial LiDAR data scanned in dense urban areas. GPS positioning, common in absolute positioning, is apt to fail in the presence of signal disturbancein dense urban circumstances, while traditional surveying methods, including traversing and leveling, are generally more costly for wider areas. The idea is that reference points, marked on top of buildings, are surveyed by GPS positioning and then feature points are relatively positioned from the reference points. The present method, if laser scanning is accompanied, gets two advantages; one is that less feature points need to be surveyed because they can be substituredby reference points, and the other is that laser scanning can be more stably carried out. The present method was shown, from the experiments, to be cost-effective against traditional ones.

Enhanced Urban Information Recognition through Correction of Shadow Effects (그림자효과 보정을 통한 향상된 도시정보 인식)

  • 손홍규;윤공현;박효근
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2003.04a
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    • pp.187-190
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    • 2003
  • Due to complexity of diverse features in urban area, accurate feature extraction is laborious task in aerial and satellite imagery. Especially occlusion by buildings, and image distortion of shadow effects make processing more difficult work. In this study, algorithm was presented to correct of shadow effects in aerial color images. This algorithm enables user to accurately interpretate urban information by correction of shadow effects in aerial color images

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The Verandah: Hong Kong's Contribution to a Southeast Asian and China-coast Urban Design

  • Faure, David
    • Journal of East-Asian Urban History
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    • v.3 no.1
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    • pp.139-160
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    • 2021
  • The verandah was a common feature of Chinese multi-storeyed houses in Southeast Asia and China. This paper argues that while an earlier version of a narrow walkway might have had its origin in Singapore, the building of an extension on the upper floors encroaching the airspace over the road skirting the building was an arrangement allowed by the colonial Hong Kong government in compensation to landlords for space devoted to ventilation. As the introduction of reinforced concrete allowed buildings to become taller, the more attractive it was to developers to incorporate the verandah design.

Revitalization of Rural Community in Less Favored Area Through Rural-Urban Exchange - Focusing on Satoyama Management Activity -

  • Miyake, Yasunari
    • Journal of Korean Society of Rural Planning
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    • v.15 no.3
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    • pp.89-97
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    • 2009
  • In less favored areas, it is getting more difficult to manage Satoyama according to aging of rural residents and depopulation. Some support of urban residents are necessary for management of Satoyama. In this paper, the role of Satoyama management activities was clarified through the analysis of the feature of activities for managing Satoyama. The questionnaire and interview surveys were done in order to clarify the actual conditions for management of Satoyama and activities of urban residents who are participating in NPO in Hyogo Prefecture. The results of analysis are as follows. (1)The form of rural-urban exchange in Satoyama is different in each Satoyama. (2)The urban residents are contributing to the region very much on both sides of the manager and the visitor in Satoyama. (3)Many urban residents visit Satoyama for the purpose of enjoying the variety of nature and culture programs in rural area. (4)There are some urban residents who participate in activities for managing Satoyama even if Satoyama is far from their residence. So it is important for rural residents to arrange the condition that they can visit rural area without difficulty.

High-resolution Simulation of Meteorological Fields over the Coastal Area with Urban Buildings (건물효과를 고려한 연안도시지역 고해상도 기상모델링)

  • Hwang, Mi-Kyoung;Kim, Yoo-Keun;Oh, In-Bo;Kang, Yoon-Hee
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.2
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    • pp.137-150
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    • 2010
  • A meso-urban meteorological model (Urbanized MM5; uMM5) with urban canopy parameterization (UCP) was applied to the high-resolution simulation of meteorological fields in a complex coastal urban area and the assessment of urban impacts. Multi-scale simulations with the uMM5 in the innermost domain (1-km resolution) covering the Busan metropolitan region were performed during a typical sea breeze episode (4~8 August 2006) with detailed fine-resolution inputs (urban morphology, land-use/land-cover sub-grid distribution, and high-quality digital elevation model data sets). An additional simulation using the standard MM5 was also conducted to identify the effects of urban surface properties under urban meteorological conditions. Results showed that the uMM5 reproduced well the urban thermal and dynamic environment and captured well the observed feature of sea breeze. When comparison with simulations of the standard MM5, it was found that the uMM5 better reproduced urban impacts on temperature (especially at nighttime) and urban wind flows: roughness-induced deceleration and UHI (Urban Heat Island)-induced convergence.

3D Line Segment Detection using a New Hybrid Stereo Matching Technique (새로운 하이브리드 스테레오 정합기법에 의한 3차원 선소추출)

  • 이동훈;우동민;정영기
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.4
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    • pp.277-285
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    • 2004
  • We present a new hybrid stereo matching technique in terms of the co-operation of area-based stereo and feature-based stereo. The core of our technique is that feature matching is carried out by the reference of the disparity evaluated by area-based stereo. Since the reference of the disparity can significantly reduce the number of feature matching combinations, feature matching error can be drastically minimized. One requirement of the disparity to be referenced is that it should be reliable to be used in feature matching. To measure the reliability of the disparity, in this paper, we employ the self-consistency of the disunity Our suggested technique is applied to the detection of 3D line segments by 2D line matching using our hybrid stereo matching, which can be efficiently utilized in the generation of the rooftop model from urban imagery. We carry out the experiments on our hybrid stereo matching scheme. We generate synthetic images by photo-realistic simulation on Avenches data set of Ascona aerial images. Experimental results indicate that the extracted 3D line segments have an average error of 0.5m and verify our proposed scheme. In order to apply our method to the generation of 3D model in urban imagery, we carry out Preliminary experiments for rooftop generation. Since occlusions are occurred around the outlines of buildings, we experimentally suggested multi-image hybrid stereo system, based on the fusion of 3D line segments. In terms of the simple domain-specific 3D grouping scheme, we notice that an accurate 3D rooftop model can be generated. In this context, we expect that an extended 3D grouping scheme using our hybrid technique can be efficiently applied to the construction of 3D models with more general types of building rooftops.

A Study on the Residential Satisfaction of Indoor Environment of Urban Traditional House in Gyeongju (도시형한옥의 실내 환경에 대한 주거 만족도 분석)

  • Choi, Moo-Hyun
    • Journal of the Korean Institute of Rural Architecture
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    • v.13 no.3
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    • pp.99-106
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    • 2011
  • The purpose of this paper is to examine their degree of housing satisfaction in Gyeongju, focused on indoor environment of urban traditional houses. Mostly built during time period from 1930's to 1980's in Seoak-dong, Bomun-dong, Namsan-dong, Sajeong-dong, and Hwangnam-dong, Gyeongju' Hanok reveals the evolutionary development to fit into the urban settlement. Urban traditional house has important meaning as a type of residence maintaining tradition of Korean residential culture, and it is the study's first goal to derive developable element by analyzing the characteristics of urban traditional house focusing on such a feature. Residents in 5 districts in Gyeongju were classified and the self-administered questionnaires were provided to them. 187 papers were used for final analysis. The data for general trend of satisfaction was seek for after its average and standard variation were calculated.

Application of Urban Hydrologic Monitoring System for Urban Runoff Analysis (도시유출해석을 위한 도시수문 모니터링 기법 적용)

  • Seo, Kyu-Woo
    • Journal of the Korean Society of Hazard Mitigation
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    • v.5 no.2 s.17
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    • pp.37-44
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    • 2005
  • It reflects well feature of slope that is characteristic of urban river basin of Busan local. In this study, process various hydrological data and basin details data which is collected through basin basis data, hydrological monitoring system(EMS-DEU) and automatic water level equipment(AWS-DEU) for urban flood disaster prevention and use as basin input data of ILLUDAS, SWMM and HEC-HMS in order to examine outflow feature of experiment basin and then use in reservoir design of experiment basin through calibration and verification about HEC-HMS. Inserted design rainfall for 30 years that is design criteria of creek into HEC-HMS and then calculated design floods according to change aspect of the impermeable rate. Capacity of reservoir was determined on the outflow mass curve. Designed detention pond(volume $54,000m^3$) at last outlet upper stream of experiment basin, after designing reservoir. It could be confirmed that the peak flow was reduced resulting from examining outflow aspect. Designing reservoir must decrease outflow of urban areas.