• Title/Summary/Keyword: Land Boundary

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COASTLINE DETECTION USING COHERENCE MAP OF ERS TANDEM DATA

  • Kim, Myung-Ki;Park, Jeong-Won;Choi, Jung-Hyun;Jung, Hyung-Sup
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.368-371
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    • 2006
  • A coastline is the boundary between land and ocean masses. Knowledge of coastline is essential for autonomous navigation, geographical exploration, coastal erosion monitoring and modelling, water line change, etc. Many methods have been researched to extract coastlines from the synthetic aperture radar (SAR) and optic images. Most methods were based on the intensity contrast between land and sea regions. However, in these methods, a coastline detection task was very difficult because of insufficient intensity contrast and the ambiguity in distinguishing coastline from other object line. In this paper, we propose an efficient method for the delineation of coastline using interferometric coherence values estimated from ERS tandem pair. The proposed method uses the facts that a tandem pair of ERS is acquired from a time interval of an accurate day and that the coherent and incoherent values in coherence map are land and water, respectively. The coherence map was generated from ERS tandem pair, filtered by MAP filter, and divided into land and water by the determination of threshold value that is based on the bimodality of the histogram. Finally, a coastline was detected by delineating the boundary pixels. There was a good visual match between the detected coastline and the manually contoured line. The interferometric coherence map will be helpful to identify land and water regions easily, and can be used to many applications that are related with a coastline.

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A Study on Korea Inland Wetland Boundary Delineation (한국 내륙습지 경계설정에 대한 제언)

  • Moon, Sang-Kyun;Koo, Bon-Hak
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.17 no.2
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    • pp.15-30
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    • 2014
  • Systematic management of wetlands should be a priority to build the data for the extent and distribution of wetlands all over the country. However there are no clear guidelines for the wetland boundary delineation, so researchers have to determine the boundary of wetlands in each different way. As a result, it is very difficult to identify the extent and distribution of wetlands. This study proposes applicable criteria of setting boundary of wetlands which consider their wetland vegetation and geographical characteristics, according to wetland classification. The proposed site in this study is selected wetlands that represent each wetland type and have been ecologically well preserved like the wetland protected areas. GIS data for setting the boundary of wetlands selected were land-cover maps, aerial photographs, high resolution satellite images, and digital topographic maps. In this study, 'wetland unit determination' of the Washington State Wetlands Rating System(WSDE, 1993) and the concept of 'Wetland and Deep-water Habitats' was suggested by Wetland Delineation Manual(USACE, 1987) were used as criteria for setting the boundary of wetlands. As a result, it was found that the boundary of wetlands could be, in general, set consistently. Also, it seemed possible to set systematic and standardized boundary of wetlands and to provide more objective data for establishing national wetland policies, if maps of wetlands are made and an investigation of wetlands is implemented according to the criteria.

Spatial Pattern of Environmental loadings on Border Region of Gyeonggi Province (경기도 접경지역 환경부하의 공간적 특성 분석)

  • 류호상;김상빈
    • Journal of the Economic Geographical Society of Korea
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    • v.7 no.2
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    • pp.157-170
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    • 2004
  • The Boundary Region in Gyeonggi Province has environmental vulnerability due to the increasing development pressure although usually regarded as an ecologically well-preserved region. This paper is aimed to analyze the status of environmental loading on natural resources of the Boundary Region in Gyeonggi Province through investigating land-use conversion pattern during the past 15 years(1985-2000), the attitude of the local community towards conservation policy, and the status of environmental treatment facilities for water quality management. The results are as follows. Firstly, the development pressure has been focused upon the southwestern part of the Boundary Region in Gyeonggi Province such as Gimpo, Paju, Dongduocheon, and Yangju since 1995. Secondly, local residents' strong aversion exists towards the conservation policy led by the government because of their underdevelopment. Finally, the risk of environmental degradation is high because the region is not equipped with adequate environmental treatment facilities for water quality management. The status of environmental loading in the Boundary Region suggests the necessity to establish a well-designed management plan for natural resources in this area.

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Seismic Evaluation of RC Special Shear Wall with Improved Reinforcement Details in Boundary Elements (경계요소의 횡보강근 상세를 개선한 RC 특수전단벽의 내진성능 평가)

  • Chun, Young-Soo
    • Land and Housing Review
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    • v.3 no.2
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    • pp.195-202
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    • 2012
  • This paper summarizes the seismic performance of two shear walls with different reinforcement details in boundary elements. One is a special shear wall designed by KBC2009 and the other is a shear wall with improved reinforcement details in boundary elements, which is a newly proposed type of special shear wall. Experimental tests under cyclic reversed loading were carried out with two 2/3 scale shear walls which were modelled from the lower part of seismic-resisting shear wall in 22-stories wall-slab apartment building. The experimental results show that seismic performance of shear wall with improved reinforcement details was almost similar to that of special shear wall with respect to the moment-drift ratio. However, energy dissipation capacity and ductility were slightly different. Also, shear wall with improved reinforcement details in boundary elements satisfied the inter-story drift limit of 1.5% from KBC2009.

An Urbanization Effect of Ruralto-Urban Land Conversion Under the Uruguay Round Agricultural Free Trade Policy : The Case of Korea (UR농산물개방에 따른 도.농 토지전용의 공간적 파급효과)

  • 최막중
    • Journal of the Korean Regional Science Association
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    • v.11 no.1
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    • pp.61-78
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    • 1995
  • This study begins with a question of what spatial impact international trade policy would have following the Uruguay Round, particularly focusing on agricultural trade liberalization in Korea. Based upon the neoclassical urban economic model, it first identifies the channel in which agricultural market opening can ultimately affect both rural and urban are as; $\circled1$ Free trade will depress domestic price of agricultural products, $\circled2$ which will in turn depreciate agricultural land price. $\circled3$ The decrease in marginal supply cost for urban land will then facilitate urban sprawl, provided that the government relaxes restrictions on urban-rural land conversion. Theoretical analysis is further refined by empirical considerations that distinguish agricultural land value solely for production purpose from that for future urban, uses, and that distinguish the urbanization effect caused by the fall in the supply cost of urban land from that caused by the existing high level of demand. Utilizing the estimate of bid-price for paddy field derived from the revenue-cost relationship of rice production, simulation results show that the urban-rural boundary under trade liberalization can expand outward up to 70-85km radius in the Seoul metropolitan area, suggesting the emergency of a metropolis or even a megalopolis which extends from Seoul to the central part of the country. Since the geographic extent of urbanization effect can vary depending upon the urban spatial structure, however, it is recommended that the redevelopment option in the built - up area should always be tied up with the issue of whether to deregulate rural-to-urban land conversion.

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Adaptive Contrast Stretching for Land Observation in Cloudy Low Resolution Satellite Imagery

  • Lee, Hwa-Seon;Lee, Kyu-Sung
    • Korean Journal of Remote Sensing
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    • v.28 no.3
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    • pp.287-296
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    • 2012
  • Although low spatial resolution satellite images like MODIS and GOCI can be important to observe land surface, it is often difficult to visually interpret the imagery because of the low contrast by prevailing cloud covers. We proposed a simple and adaptive stretching algorithm to enhance image contrast over land areas in cloudy images. The proposed method is basically a linear algorithm that stretches only non-cloud pixels. The adaptive linear stretch method uses two values: the low limit (L) from image statistics and upper limit (U) from low boundary value of cloud pixels. The cloud pixel value was automatically determined by pre-developed empirical function for each spectral band. We used MODIS and GOCI images having various types of cloud distributions and coverage. The adaptive contrast stretching method was evaluated by both visual interpretation and statistical distribution of displayed brightness values.

Extracting Land Cover Map and Boundary Line between Land and Sea from Hyperspectral Imagery (하이퍼스펙트럴 영상으로부터 객체기반 영상분류방법에 의한 토지피복도 및 수애선 추출)

  • Lee, Jin-Duk;Bhang, Kon-Joon;Joo, Young-Don;Han, Seung-Hee
    • Proceedings of the Korea Contents Association Conference
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    • 2014.11a
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    • pp.69-70
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    • 2014
  • 연안지역에 대한 항공 하이퍼스펙트럴 영상으로부터 객체기반 분류방법을 이용하여 토지피복분류를 수행하고 기존에 주로 사용되어온 화소기반 분류기법에 의한 결과와 비교하였으며, 생성된 토지피복도로부터 해륙경계선인 수애선벡터를 용이하게 추출하는 방법을 제시하였다.

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Correlations between Spatial Distribution of Alien Plants and Land Cover - Focused on National Ecosystem Survey - (외래식물의 공간분포와 토지피복간의 상관성 연구 - 전국자연환경조사 자료를 중심으로 -)

  • Jung, Tae-Jun;Shin, Hyun-Chul;Shin, Young-Kyu;Kim, Myung-Jin
    • Journal of Environmental Impact Assessment
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    • v.22 no.5
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    • pp.455-466
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    • 2013
  • The aim of this study is to seek application plans of National Ecosystem Survey database based on comparison and examination of feasible analysis methods for distribution characteristics of alien plants. In order to set up a correlation analysis method between alien plants and environmental factors, we had reviewed the 3rd National Ecosystem Survey guide book and consequently, two kinds of analysis method were tested. One was 1/25,000 scale map boundary based analysis and the other was representative mountain area based analysis. In this study we restricted the research area to select reliable surveyed database from whole "2011 National Ecosystem Survey flora database" according to two major criteria. First, an area defined by 1/25,000 scale map boundary and representative mountain area where the number of surveyed flora records should be within top 20%. Second, land cover map should also be built up inside that area. As a result, 25 map boundaries and 25 representative mountain areas were extracted to be analyzed. To limit a boundary for every representative mountain area we had analyzed distribution of environmental factors around that area by manual inspection with SPOT-5 remote sensed satellite image then designated 3km buffer zone from each alien plant location in that area. After then, naturalized index (NI) and urbanized index (UI) was calculated and correlations analysis was carried out. With the result of correlation analysis by map boundary only agricultural land area showed significant value of r (0.4~0.6, correlated) and the rest of factors did not. In the case of representative mountain area, the result showed that agricultural land, road and forest area showed significant value of r (0.6~0.8, highly correlated) which was corresponding to existing researches. Therefore, representative mountain area based method is preferable when using the alien plants database of National Ecosystem Survey for species distribution analysis. And also, considering the way of database utilization is strongly suggested at the first stage of survey planning for promoting active use of national ecosystem survey database.

Effectiveness Analysis According to the Affiliation of Linear SOC Projects and Cadastral Resurvey Project (선형 SOC 사업과 지적재조사측량의 연계에 따른 효과 분석)

  • Lee, Byoungkil;Yoon, Jong Sung;Son, Jong Young
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.spc4_2
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    • pp.393-400
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    • 2014
  • "Master Plan of Cadastral Resurvey Project" aims to put the governmental budget of 1.3 trillion Won into the cadastral resurvey project until 2030 that reflects the preliminary feasibility study, conducted by government at 2012. The cadastral Resurvey, which takes 78.8% of the expenses in the project, has to take an critical role for earning the most effective results from the project. The cadastral confirmation surveying take up almost 13% of the project and is controlled under the areal SOC(Social Overhead Capital) projects in current "Master Plan of Cadastral Resurvey Project". Also, the affiliations of cadastral resurvey and linear SOC projects are expected to bring advanced results, although those are excluded from cadastral confirmation surveying. For linear SOC projects, the land division survey is conducted by using boundary stakes in boundary survey, while the cadastral resurvey is conducted within the SOC project area, after the completion of the project. In this study, we could conclude that cadastral resurvey results with the world geodetic system from boundary survey at the point of land division could be produced without the duplication of land division and cadastral resurvey. As a result, the expected benefits are 73,877 parcels and 4,078 million won, annually.

A Study on the Amendment of Criteria for Establishment of Area damaged by the Airport Noise : Drawing a Boundary Line of the Damaged Area (항공기소음피해지역 설정 기준의 개선방안에 관한 고찰 : 피해지역 경계선 획정에 관하여)

  • Lee, Jun-Ho;Lee, Ki-Ho
    • Journal of Environmental Science International
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    • v.18 no.10
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    • pp.1143-1153
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    • 2009
  • The purpose of this study is to propose an appropriate method for marking out a boundary line of area damaged by aircraft noise. In an actual situation, there are many gaps between the boundary line of aircraft noise contour and the boundary line of an occupant of a house. Three cases faced in practice are considered in this study. Case I is considered the land number together with sub-number. The Tong and Ban (the residential district number in Korea) are considered in Case II. In Case III, the configuration of ground is examined. The authors expect that the authority of aviation affairs should choose one of these cases and put in force in the near future.