• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.869-874
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• 2004

Digital TV broadcasting's resolution or tone quality is very excellent than analog broadcasting and has many advantages including various multimedia functions such as home shopping, home banking, internet search, telecommuting, VOD, etc. In this study, it is essential to analyze the regional electromagnetic environment before Digital TV broadcasting, and therefore we analyzed Busan area's limitation using ETRI propagation model. For maintaining high-quality Digital TV signals, we measure electric field intensity wide and far in Busan including mountains area and high-rise buildings. Generally, it has lower value by a standard ETRI propagation model than simulated value about standard model, but distribution pattern are similar with it. Compared theoretical values with the measured results, they have similar values for flat area but very different values for crowded city area and mountains area So we conclude that ETRI propagation model and theoretical model are not suitable for Busan in a free space.

• Journal of the Korea Knowledge Information Technology Society
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• v.12 no.1
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• pp.69-78
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• 2017

KOIN (Korean medicine 人, http://www.koin.re.kr) is a Korean medicine knowledge portal developed for users who are interested in Korean medicine to share relevant information. The purpose of the present study is to seek methods for advancing the quality of the contents and services of KOIN to secure future users of the portal services before fully initiating the KOIN service. The crowd testing method was applied to test the functionality and usability of the current KOIN service, and domestic and international websites providing similar services were investigated and analyzed. About 150 errors were found in this functional testing procedure, but the identified functional problems were all corrected. An average score of 3.33 was calculated in the usability test, in which the reliability and the playfulness showed the highest and lowest score, respectively. We in this paper surveyed the 15 relevant websites with respect to KOIN in the traditional medicine and the modern medicine fields. The strengths and weaknesses of similar websites were analyzed to improve the KOIN services. In particular, it is shown that the evidence-based Korean medicine knowledge is KOIN's biggest strength. Users' needs and demand for the KOIN services will be continuously gathered to provide the Korean medicine knowledge services that the users require.

• Spatial Information Research
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• v.19 no.4
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• pp.21-31
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• 2011

As large scaled natural or man-made disasters being increased, the demand for rapid responses for such emergent situations also has been ever-increasing. These responses need to acquire spatial information of each individual site rapidly for more effective management of the situations. Therefore, we are developing a close-range real-time aerial monitoring system based on a low altitude unmanned helicopter. This system can acquire airborne sensory data in real-time and generate rapidly geospatial information. The system consists of two main parts: aerial and ground parts. The aerial part includes an aerial platform equipped with multi-sensor(cameras, a laser scanner, a GPS receiver, an IMU) and sensor supporting modules. The ground part includes a ground vehicle, a receiving system to receive sensory data in real-time and a processing system to generate the geospatial information rapidly. Development and testing of the individual modules and subsystems have been almost completed. Integration of the modules and subsystems is now in progress. In this paper, we w ill introduce our system, explain intermediate results, and discuss expected outcome.

• Spatial Information Research
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• v.21 no.4
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• pp.15-24
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• 2013

Recently, as the spatial information and various multimedia are fused together, the demand for the high value-added spatial information contents and the necessity of technology for spatial information security are increasing. However, since the current security policy is being managed independently by each system, there is a problem with unreliable or costly to modify or revise the security policy. Such problems occur frequently in the process of coordination or integration of the spatial information management systems that are used in public institutions and private companies. Therefore, in this paper, the access control system that could provide an integrated security policy for many spatial platforms and systems with expandable grammar and semantics was designed and implemented based on GeoXACML proposed by OGC. As the GeoXACML-based access control system designed and implemented in this paper follows the international standard specifications, it provides high portability and interoperability. Finally, in this paper, the efficiency of the system was proved by applying it to a virtual scenario on the military area requiring the access control.

• Spatial Information Research
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• v.12 no.4 s.31
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• pp.299-305
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• 2004

According to the facility of effective search and user-friendly access to various spatial data by building GIS, the demand for application of information and social effect has been increased. To meet such domestic demands, it has become necessary to develop local, regional, and global SDI(Spatial Data Infrastructure) which can support discovery, access, and use of spatial information in the decision-making process. Many developed countries are implementing and managing GSDI in accordance with their state and purpose. There are two typical international cases; U.S. Geospatial One-Stop and European Geo-Portal. These systems are observed the international standards so they provide standardization and interoperability of GI. In domestic cases, however, each sector is managing separately geospatial data management systems. From this point of view, this paper proposed implementation approaches of GOS that can provide interchange of geospatial information between supplier and user. This paper focused on standardization, considered technical and political factors and analyzed two cases of GOS such as U.S. and Europe cases into our spatial information environments. It is possible to search and access geospatial data effectively by introducing GOS. In addition, it is possible to promote popularization of geospatial information and development of GIS industy.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.1
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• pp.78-92
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• 2019

This study aims to evaluate the efficiency in the provision of employment services for the middle-aged by using spatial analysis in GIS. Based on location information of employment service institutions, we find service areas of the institutions and calculate regional rates of duplication and exclusion in terms of spatial coverage of the employment services. Taking into account potential demand for employment services, the regions with high priority in the provision of the services are identified. Among the regions, those with high exclusion rate of the services are designated as the regions of insufficient service level. Results indicate that Namyangju-si is a representative region of insufficient employment service level. To improve efficiency in the provision of employment services, we suggest to relocate employment service institutions that have been located in a region of high duplication rate such as Siheung-si, Danwon-gu, Gangnam-gu, Songpa-gu into the locality of Namyangju-si.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.84-99
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• 2021

As the micro-mobility market grows, the demand for route guidance, that includes uphill information as well, is increasing. Since the climbing angle depends on the electric motor uesed, it is necessary to establish an uphill road DB according to the threshold standard. Although road alignment information is a very important element in the basic information of the roads, there is no information currently on the longitudinal slope in the road digital map. The High Definition(HD) map which is being built as a preparation for the era of autonomous vehicles has the altitude value, unlike the existing standard node link system. However, the HD map is very insufficient because it has the altitude value only for some sections of the road network. This paper, hence, intends to propose a method to generate the road longitudinal slope using currently available data. We developed a method of computing the longitudinal slope by combining the digital elevation model and the standard link system. After creating an altitude at the road link point divided by 4m based on the Seoul road network, we calculated individual slope per unit distance of the road. After designating a representative slope for each road link, we have extracted the very steep road that cannot be climbed with personal mobility and the slippery roads that cannot be used during heavy snowfall. We additionally described errors in the altitude values due to surrounding terrain and the issues related to the slope calculation method. In the future, we expect that the road longitudinal slope information will be used as basic data that can be used for various convergence analyses.

• Korean Journal of Remote Sensing
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• v.39 no.5_4
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• pp.1165-1172
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• 2023

Recently, Korea has declared carbon neutrality by 2050. The Korea Forest Service is promoting the precision and high technology of forest resource surveys. As such, the demand for forest resource management is increasing, and the need to build a digital twin of forest space is increasing. However, to date, digital twin has only built and provided virtual city services, which are city and nationwide digital twin environments. Three-dimensional digital twin services targeting forest space are not operated and provided. Therefore, in this study, we aimed to implement a forest digital twin environment to provide 3D forest spatial information services corresponding to vertical information such as tree-level height and thorax diameter. By lightweighting realistic 3D tree models and applying 3D Tiles, we confirmed the feasibility of implementing a forest digital twin environment for 3D forest spatial information services. Through continuous research, we plan to implement a forest digital twin that can deploy and service 3D tree models for trees nationwide, including street trees in urban areas. This is expected to enable the development of forest digital twin services for forest resource management.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.205-214
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• 2015

Rapid urbanization and industrialization have caused increased demand for underground structures such as cable, and other utility tunnels. Recently, it has become very difficult to construct new underground structures in downtown areas because of civil complaints, and engineering problems related to insufficient information about existing underground structures, cable tunnels in particular. This lack of information about the location and direction-of-travel of cable tunnels is causing many problems. To solve these problems, this study was focused on the use of geophysical exploration of the ground in a way that is theoretically, different from previous electrical resistivity surveys. An electric field analysis was performed on the ground with cable tunnels using Gauss' law and the Laplace equation. The electrical resistivity equation, which is a function of the cable tunnel direction, the cable tunnel location, and the electrical conductivity of the cable tunnel, can be obtained through electrical field analysis. A field test was performed for the verification of this theoretical approach. A field test results provided meaningful data.

• Journal of Korean Society of Transportation
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• v.25 no.6
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• pp.197-208
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• 2007

Enormously sized buildings are appearing world-wide with the advancement of construction techniques. Large-scaled and complicated structures will have increased difficulties for dealing with safety, and will demand well-matched safety measures. This research introduced up-to-date techniques and systems which are applied in buildings in foreign nations. Furthermore, it proposed s direct guidance plan for buildings in case of fire. Since it is possible to install wireless sensor networks which detect fires or effects of fire, the plan makes use of this information. Accordingly, the authors completed a direct guidance plan that was based on omnidirectional guidance lights. It is possible to select a route with concern about both time and capacity with a concept of a non-dominated path. Finally, case studies showed that quickest path algorithms were effective for guiding efficient dispersion routes and in case of restriction of certain links in preferred paths due to temperature and smoke, it was possible to avoid relevant links and to restrict demand in the network application. Consequently, the algorithms were able to maximize safety and minimize evacuation time, which were the purposes of this study.