• Title/Summary/Keyword: geographic environment

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Storage Feature-Based Watermarking Algorithm with Coordinate Values Preservation for Vector Line Data

  • Zhou, Qifei;Ren, Na;Zhu, Changqing;Tong, Deyu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.7
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    • pp.3475-3496
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    • 2018
  • Most of current watermarking algorithms for GIS vector data embed copyright information by means of modifying the coordinate values, which will do harm to its quality and accuracy. To preserve the fidelity of vector line data and protect its copyright at the same time, a lossless watermarking algorithm is proposed based on storage feature in this paper. Firstly, the superiority of embedding watermark based on storage feature is demonstrated theoretically and technically. Then, the basic concepts and operations on storage feature have been defined including length and angle of the polyline feature. In the process of embedding watermark, the watermark information is embedded into directions of polyline feature by the quantitative mechanism, while the positions of embedding watermark are determined by the feature length. Hence, the watermark can be extracted by the same geometric features without original data or watermark. Finally, experiments have been conducted to show that coordinate values remain unchanged after embedding watermark. Moreover, experimental results are presented to illustrate the effectiveness of the method.

An Adaptive Watermark Detection Algorithm for Vector Geographic Data

  • Wang, Yingying;Yang, Chengsong;Ren, Na;Zhu, Changqing;Rui, Ting;Wang, Dong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.1
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    • pp.323-343
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    • 2020
  • With the rapid development of computer and communication techniques, copyright protection of vector geographic data has attracted considerable research attention because of the high cost of such data. A novel adaptive watermark detection algorithm is proposed for vector geographic data that can be used to qualitatively analyze the robustness of watermarks against data addition attacks. First, a watermark was embedded into the vertex coordinates based on coordinate mapping and quantization. Second, the adaptive watermark detection model, which is capable of calculating the detection threshold, false positive error (FPE) and false negative error (FNE), was established, and the characteristics of the adaptive watermark detection algorithm were analyzed. Finally, experiments were conducted on several real-world vector maps to show the usability and robustness of the proposed algorithm.

The Building of the Environmental and Geographic Information System Based upon the Administrative Boundary (행정구역기반 환경지리정보시스템 구축방안)

  • Cho, Deokho;Bae, Min-Ki
    • Journal of the Korean Association of Geographic Information Studies
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    • v.8 no.1
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    • pp.96-113
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    • 2005
  • The goal of this study is to build the environmental and geographic information system according to the administrative territory in Gyeongbuk province in order to resolve the mismatch between the environment attribute information and geographic information system. In order to do that, this study reviews the characteristics of local geographic information system and environmental attribute information. After that, this paper tries to figure out the way of integration between geographic and environmental informations using the administrative unit code. The result of this study can provide the basic database for building the environmental policy and improve the reality of policy analysis because this method can provide the environmental attribute database with the administrative territory information. And it will contribute to improve the environmental management system and to build the other attribute databases for the local government.

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Simulating Pedestrian Evacuation Using Geographic Information Technologies

  • Jingjing, Shi;Hui, Lin
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.414-416
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    • 2003
  • Pedestrian assemblage is now a normal phenomenon in modern cities. To maintain an unblocked traffic situation, protect the pedestrians' safety and make preparedness for any emergencies is an important task for police department. Modeling pedestrian dynamics and simulating evacuation process can provide useful information for make accurate decisions. In this paper, by virtue of geographic information technologies, the authors proposed a conceptual framework to simulate pedestrian dynamics and evacuation in an open urban environment.

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The Geographic Environment of Hwaam Cave Area

  • Hong, Chung-Ryol;Won, Pyong-Kwan
    • Journal of the speleological society of Korea
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    • no.4
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    • pp.23-32
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    • 1996
  • The geographic environment means the general state of the environment in the area. Especially, which means the generation cause, the development process of the cave, and the validity of cave development and conservation in the side of the place of the cave. This study put emphasis on lying in which place Hwaam cave in Tong-myon, Chong son-gun, Kangwondo is situated and having in which stand is in comparison with other districts, and how the geological structure which determine the cave forming cause is.(omitted)

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Geographic variation in the acoustic signals of black-billed magpies (Pica pica) in South Korea and Japan

  • Lee, Sang-Im;Lee, Sun-Hee;Nam, Hyun-Young;Choe, Jae-Chun
    • Journal of Ecology and Environment
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    • v.34 no.2
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    • pp.167-174
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    • 2011
  • Black-billed magpies (Pica pica) are a highly sedentary species due to their short and round wings, which are not adequate for long distance flights. We investigated geographic variation in the vocal signals of magpies residing in South Korea and Japan (subspecies sericea). Based on the magpie's limited dispersal ability, we predicted that the variation in vocal signals of black-billed magpies could be explained by geographic barriers such as mountain ranges and straits. We analyzed four-syllable chatter calls of magpies from five localities in South Korea, which are separated by mountain ranges (Seoul, Daejeon, Daegu, Gwangju, and Busan), and two island localities separated from the mainland by straits (Jeju in Korea and Saga in Japan). We found significant differences in the characteristics of magpie chatter calls recorded in the seven localities, and the variation pattern was independent among the variables. Mainland-island differentiation and north-south differentiation were observed. In general, magpies on Saga were the most distinctive. North-south differentiation was observed among the Korean mainland localities. However, the pattern was not related to the presence of putative geographic barriers. We hypothesize that the patterns of geographic variation in the structure of magpie chatter calls residing in South Korea might have been shaped by a sudden expansion of magpies followed by low level of local isolation, which may have led to vocal differentiation. Along with elucidating the vocal environment of Korean magpie populations, more extensive sampling is needed to clarify the functional aspects of geographic variation in the vocal signals of Korean magpies.

Assessment of 3-Dimensional Sunshine Environment Using Geographical Information System Data around Pukyong National University (부경대학교 주변 지역의 지리정보시스템 자료를 이용한 3차원 일조 환경 평가)

  • Kim, Eun-Ryoung;Park, Soo-Jin;Kim, Jae-Jin;Nam, Kyung-Yeub
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.3
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    • pp.116-131
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    • 2014
  • In this study, sunshine environment in an urban area is analyzed using a numerical model which considers sunshine-duration blocking by topography and buildings. The numerical model used in this study has an improvement in the algorithm detecting sunshine duration in the model domain. The main improvement in the algorithm is to detect sunshine duration using all the surfaces of any grid cell(the previous model uses the center of any grid cell). The improvement in the algorithm gives more accurate evaluation of sunshine duration at corner surfaces of buildings. Using the improvement model and geographic information system(GIS) data, sunshine environment is analysed at an building-congested area in Busan for a week in four seasons. The results show that sunshine duration can be much changed by apartment complexes, high-rise buildings, topography in the model domain.

Analysis of Regional Environment in the Nak-Dong River Watershed using Geographic Information System (지리정보시스템을 이용한 낙동강 유역권의 광역환경분석)

  • Jung, Sung-Kwan;Park, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.3 no.1
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    • pp.12-22
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    • 2000
  • Recently urbanization and industrialization around the Nak-dong river watershed have lead to the regional environmental problems. In this viewpoint, we took up variables which were related to watershed environment, and found out spatial and environmental properties of the Nak-dong river using factor analysis, ANOVA test and geographic information system. The results may be summarized as follows; three common factors which were named as urban, agricultural and industrial pollutant factor extracted from statistical methods. Spatial distribution of watershed environment could be found by connection attributes of factor scores derived from factor analysis to digital map using GIS. According to the results, distribution of pollutant sources were concentrated in the main stream of the Nak-dong river and its tributaries, Kum-ho river. So it is necessary to manage the watershed environment in due consideration of environmental carrying capacity.

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A Land Capability Analysis in Kyungsan, Korea Using Geographic Information System (지리정보시스템(GIS)을 이용한 경산시의 토지잠재력 분석)

  • 오정학;정성관
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.3
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    • pp.34-44
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    • 1998
  • The purpose of this study is to provide the basic data for land use in the future, which result from analyzing land use, obtained after studying on the natural environment by Geographic Information System and Remote Sensing. The results of this study are as follows : ·According to the classification of land-cover, agricultural land use is relatively prominent except for overall natural covering. According to the average value of Green Vegetation Index class, the average value of GVI is 3.0, and 45% of the regions have relatively good condition of floral state. ·With a view to natural environment, the survey shows that the altitude of 90% of the total areas is below 400m, and most of them are flattened or moderately-inclined area. Therefore, this region has a good condition to be used for development. · The area for the first class in preservation degree of natural scenery of Namcheon-Myun is 2.3% of the total areas. According to the results about unstable areas on all sides, unstable districs are distributed in so small-scale units that they will be safe from some damages drawn by developing activity. But we have to consider every aspects for the future development of them. In this study, the natural environment-variables are regarded firstly, and effective designation of the land with natural environment is researched too. However, to establish more practical developing plan, ecological and human variables should be regarded.

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