• Journal of Communications and Networks
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• v.11 no.4
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• pp.327-336
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• 2009

Geographic routing has been considered as an attractive approach in wireless sensor networks, since it routes data packets by using location information rather than global topology information. In geographic routing schemes, packets are usually sent along the boundary of a hole by face routing to detour the hole. As result, all data flows which need to detour the hole are concentrated on the boundary of the hole. This hole detour scheme results in much more energy consumption for nodes at the hole boundary, and the energy exhaustion of hole boundary nodes enlarges the holes. This is referred to as a hole diffusion problem. The perimeter mode may also lead to data collisions on the hole boundary nodes if multiple data flows need to bypass a hole simultaneously. In this paper, we propose a hole modeling and detour scheme for geographic routing in wire-less sensor networks. Our hole modeling and detour scheme can efficiently prevent hole diffusion, avoid the local minimum problem faced by geographic routing protocols, and reduce data collisions on the hole boundary nodes. Simulation results show that the proposed scheme is superior to the other protocols in terms of control overhead, average delivery delay and energy consumption.

• Journal of the Korean Geographical Society
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• v.31 no.1
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• pp.38-48
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• 1996

Value objectives have been relatively neglected in geography education. Then in this study I reviewed some value objectives and their contents which have been discussed in geographic education and curriculum in secondary education. Value objectives which are reviewed in geographic education, are regional consciousness, loving home country and nation, international understanding and citizenship, art of landscape, natural and environmental beauty, and human right. But values objectives in geography curriculum are included value incalculation: national development, participation in economic development, etc.. Namely development education is more emphasized than individual life and experience in geographic education. Value objectives should be on the basis of social education and citizenship education for geographic education. Futhermore, it is required to develop teaching methods which help student's socialization and social competence through geography education focused on value objectives and their content.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.4
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• pp.22-33
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• 2006

The objective of this paper is to discuss geographic information policies and strategies of British government and suggest effective policies for Korea National GIS project GIS that has been implemented geographic information infrastructures into public sectors and private markets for the last ten years. To obtain the research aim, this paper reviews the main factors of the Britain GIS project such as distribution structure and process of GI markets, government policies and strategies that are led by Ordnance Survey, most leading mapping agency in the UK. In conclusion, some issues have been explored with reference to the experiences of the Britain GIS projects. The first of these is the nature of geographic information and the second concerns the notion of the circulation policies of spatial data, and the last proposes Korea GIS policies and strategies for successful geographic information and spatial data implementation. The findings of the analysis of the Britain GIS development indicate that a shift began to take place from central government coordinate toward more extensive utilization of private and commercial sectors. This reflects both the increasing importance of geospatial data circulation in all levels of GIS stakeholders. Finally these discussions are particularly to be the issues where multi-agency collaboration of Korea government is concerned and can take the form of joint ventures by consortiums of both involving data producers and data users in order to increase commercial participation for value-added geospatial items, and to encourage both research and development sectors with low or free price policies.

• Journal of the Korean GEO-environmental Society
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• v.14 no.2
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• pp.19-29
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• 2013

The objective of this study is to develop a new GIS Model for calculating the hydrological geographic parameters efficiently using ArcGIS ModelBuilder. To evaluate the applicability of the new GIS Model, hydrological geographic parameters calculated by WMS and HEC-GeoHMS were compared with 5 geographic parameters from the new GIS Model. 18 reservoirs in Chungdo-gun were selected for this study. Hydrological geographic parameters used in this study are watershed area, stream length, watershed slope, stream slope and curve number. As the results of this study, the average relative error of 5 geographic parameters from all watersheds is shown more than 10.00%. In the results by the new GIS Model, hydrological geographic parameters are better efficiently and accurately to evaluate than those existing models.

• Journal of Cadastre & Land InformatiX
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• v.47 no.2
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• pp.201-212
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• 2017

The purpose of this study is to identify the problems of the present status of the Jeollanamdo's geographical name task by analyzing it and to suggest ways to improve it. For this purpose, the theoretical review including the definition of the geographical name as the subject of the study is conducted. Also, by analyzing the current structure of geographical name, the enactment and improvement of the ordinance of the committee on geographical name, and the management of committee on geographical name etc, the problems of the geographical name task are derived and suggestions for improvement are proposed. The results of this study are as follows: First, as a plan to improve the professionalism of the organization and the officer in charge of the geographical name task, this study suggests the unification of the department in charge of geographical name task, the specialization of the official in charge, and the development of training and teaching materials related to the geographic name task. Secondly, in order to improve the ordinance and the management of the committee on geographical name, this study suggests the enactment and improvement of the ordinance of committee on geographical name, the guidance and the supervision of the establishment and operation of the committee on geographic name, the simplification of procedures of establishing and changing geographical name, and enactment of geographic name a Law.

• Journal of the Korean Association of Geographic Information Studies
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• v.1 no.2
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• pp.56-66
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• 1998

The primary goal of the database design is to organize a large amount of data effectively in users and systems view point. Effective design of a database is very important for processing applications efficiently. In this paper, we discuss database design for an urban geographic information system that effectively maintains the cadastral and planimetric information. We first collect and analyze the requirements for the target urban geographic information system and then perform database design for these requirements. Our database design is based on the object-oriented approach that has rich expressive power and good reusability in comparison with the traditional relational approach. Especially, we employ the OMT, one of the most widely-used object-oriented models. We expect that our result would be helpful in building large databases for urban geographic information systems practically.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.9B
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• pp.847-856
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• 2009

In geographic routing for wireless sensor networks, sources need the location of sinks destined for delivering their data packets. Most of the existing geographic routing protocols merely assume that the sources can get the locations of sinks by some location service. How source nodes find out the location of sinks is not easy. In this paper, we propose a sink location dissemination scheme in geographic routing for wireless sensor networks. In this scheme, a source node and a sink node send sink location announcement and query messages along two paths respectively by geographic routing. The node located on the crossing point of the two paths informs the source about the sink location. Then the source can send data packet to the sink by geographic routing. How to guarantee that these two paths have at least one crossing point in any irregular profile of sensor network is the challenge of this paper Simulation results show that our protocol is significantly superior to other protocols in terms of energy consumption and control overhead.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.2
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• pp.87-96
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• 2004

When watershed spatial database is constructed from DEM, hydrological geographic characteristics of watershed can be easily extracted. And the characteristics can be assigned and managed as the attribute of spatial database. In this study the scheme of constructing framework spatial database which is basic information for managing watershed information is examined. We established framework spatial data and defined the relationship of the data. And framework spatial database of test site was constructed. In this study, HyGIS(Hydrological Geographic Information System) which is developed by domestic technology for making hydrological spatial data and developing water resources system is used. Hydrological geographic characteristics and spatial data is extracted by HyGIS. And the data from HyGIS is used for constructing framework spatial database of test site. Finally, this study suggests the strategy of constructing framework spatial database for developing watershed management system based on river network.

• Journal of the Speleological Society of Korea
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• no.72
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• pp.37-46
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• 2006

The purpose of this study is to provide a basic theory of photogeography. There is a close relationship between photos and fine arts, but lots of differences. For examples photos are arts of cognition, analytic media and time. Geographic photos are photos useful for geography. Geographic-photos are a kinds of academic photos which deals with special meaning of geographic phenomena and cognition of the certain area. According to the nature the photos available for geography, can be grouped into geographic photos and general photos. Geographical ideas, photographical skills and artistic senses are necessary to the photogeographers. Geographic photos are useful for research and educational Purpose. The aspect of research is related to the systematic geography, for example ; geomorphology, historical geography etc. In conclusion, to the photo geographer the geographic idea is more necessary than the skill of photography.

• Journal of the Korean association of regional geographers
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• v.10 no.3
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• pp.579-591
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• 2004

Recently more emphasis thinking is domain-specific by cognitive psychologists, because problem solving needs domain-specific knowledge. Improving students' geographical thinking should ensure that geographic skills are used when developing teaching-leaming objectives. Knowledge is undoubtedly important, but for the purpose of the teaching of geography thinking, skills are critical. The purpose of this paper is to make specification of geographic skills as a frame of reference for instructional objectives. Based on cognitive psychology, this paper examined the interdependence relationship between thinking and knowledge. Next, we attempt to conceptualize high order geographical thinking and relatively lower order geographic skills and to explore specification of geographic skills in complex thinking strategical perspectives.