• Journal of radiological science and technology
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• v.30 no.3
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• pp.237-243
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• 2007

Phantoms are very necessary for quality assurance of radio nuclides imaging systems to maintain standards and to ensure reproducibility of test. General quality assurance and instrument quality control are essential in every hospital. The human tissue equivalent materials are aluminum, areryl, water and epoxy..etc. It is very important to select optimum equivalant materials for a phantoms in QC. Especially, paraffin is very similar with human soft tissue in X or Gamma-ray physical characteristics and easy to buy with economically. We made a paraffin thyroid phantom and compare with thyroid areryl phantom, also used commercially in practice. Two small size cold spots(3 and 6 mm diameter) and a hot spot(3 mm diameter) embeded in paraffin phantom. And imaged with $^{99m}TcO_4$ by camera for analysis about spatial resolution and noise at the hot and cold spots. We got some results as below : 1. No difference in counting rate and noise between both arcryl and paraffin thyroid phantoms. 2. The best spatial resolution can be seen 6 cm distance between pinhole collimator and thyroid phantoms(arcryl and paraffin). 3. More optimal spatial resolution could acquired in paraffin thyroid phantom. Paraffin is very similar with human soft tissue in atomic number, density and relative absorbtion function, and can be shaped easily what we wanted. So we can recommendation paraffin as quality assurance phantom because its usefulness, economical benefit and purchasability.

• Journal of the Korean GEO-environmental Society
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• v.15 no.6
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• pp.17-29
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• 2014

A remedial investigation was conducted at five military training ranges in northern Gyeonggi province to collect information necessary for the design of on-site treatment facilities for the abatement of explosive compounds release to the environment. These information includes (i) identification of dominant explosive compounds in each range, (ii) discharge/migration routes, and (iii) contaminant distribution in particle size fraction and settling velocity of the soils. The results of investigation showed that TNT and RDX are the major contaminants but the extent of contamination varied depending on the types of military training practices and topography of the site. RDX was also detected in the subsurface soil and in the nearby stream within the training ranges, suggesting release of contaminants to streams. The median concentrations of explosives in the surface soil were less than 20 mg/kg despite several 'hot spots' in which explosives concentrations often exceeds several hundred mg/kg. The average clay contents in the soil of target area was less than 5 % compared to 12 % in the control, indicating loss of smaller particles by surface runoff during rainfall due to lack of vegetative land cover. Analysis of explosive compounds and particle size distribution showed that the amount of explosive compounds in soil particles smaller than 0.075 mm was less than 10 % of the total. Settling column tests also revealed that the quantity of explosive compounds in the liquid phase of the effluent was greater than that in the solid phase. Therefore, pre-treatment of particulate matter in surface runoff of shooting range with a simple settling basin and subsequent effluent treatment with planted constructed wetlands as polishing stage for explosives in the aqueous phase would provide the shooting ranges with a self-standing, sustainable, green solution.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.3
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• pp.54-69
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• 2023

This study investigated the distribution of users in urban parks to overcome the limitations of existing research, which made it difficult to determine where data came was collected. It aimed to provide implications for park planning and management based on user distribution using mobile signal data. Five urban parks in Seongdong-gu, Seoul, with various physical characteristics, were selected. Mobile signal data provided by the Seoul Big Data Campus was used to identify the distribution of user inflow through hot spot analysis per park. The relationship between urban context and park influence area was derived. Seoul Forest (P1) and Seongsu Park (P3), which have a high proportion of commercial spaces around the park, showed wider user hotspots compared to Eungbong Park (P2), Dokseodang Park (P4), and Daehyunsan Park (P5), which were located in residential areas. Parks with a significant presence of commercial spaces had a broader influence, while parks with larger sizes and gentle slopes exhibited wider influence areas. This study proposed a novel data-based approach to urban park planning and management based on the inflow distribution of park users. Through this research, valuable insights were derived that could be utilized for urban park planning and management, aiming to enhance the effectiveness and efficiency of park utilization.

• Journal of Korean Society of Transportation
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• v.31 no.4
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• pp.47-57
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• 2013

This study aims at analyzing transportation equity between geographical areas of Gyonggi Province, by taking both the transportation infrastructure and travel behavior into account. Indicators of transportation infrastructure include the indices of road infrastructure, transit infrastructure and regional characteristics. Travel behavior concerns information from bus card data on a survey day. The hot-spot analysis conducted included spatial cluster analysis and global/local regression analyses. The analysis results identified geographical areas of four different classes of transportation equity, from the area with high level infrastructure surrounded by the areas with high level infrastructure (HH) to the area with low level surrounded by the areas with low level (LL). The area of HH type showed big numbers of passengers, trips and transfers, whereas the area of LL type shows big figures of internal trip frequency, travel time, travel distance, travel speed and transit fare. Global regression analysis showed that number of passengers, number of transfers, number of internal trips and mean travel speed are important to the level of transportation infrastructure. GWR with these four significant variables significantly improved the AICs and ANOVA results, which implies that the infrastructure is likely explained by travel characteristics differently between geographical areas in Gyonggi Province.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.3
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• pp.36-45
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• 2018

Cemeteries in the United States are frequently observed near residential areas in cities even though they are spaces for the dead. However, it has not been fully studied when and how cemeteries were formed in the process of urbanization. Thus, this research aimed to investigate the spatial structure and historical change of cemeteries in Seattle due to urbanization, focusing on the contextual relationship between cemeteries and the surroundings according to two time periods: the early formation period of cemeteries in Seattle and the current period. For this, a mixed method was taken in this paper that combined historical analysis based on old references and historic maps with cluster analysis using GIS. In conclusion, the research found that early cemeteries of Seattle in downtown areas were introduced as by-products of urban formation, but the cemeteries in the suburbs were established ahead of urban growth and neighborhood development. In addition, Seattle's cemeteries not only showed a similar locational pattern to Seattle's shopping centers, but also were positively associated with population distribution given the Hot Spot Analysis. In other words, Seattle's cemeteries were originally located in rural areas, but later came to be located in urban areas, sustaining the landscape of American rural cemeteries.

• Journal of the Korean Regional Science Association
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• v.36 no.2
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• pp.37-49
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• 2020

Currently, the average aging rate has reached 14.8% in our country, despite the residents are aging or over the average aging rate has reached 31.8% with a population of less than 100,000. Various convenience facilities are concentrated in the town center, causing inconvenience to use. The main purpose of this study is to analyze the accessability of living convenience facilities in this area. This study builds on the population aging of the research target area and distribution of living facilities for the elderly based on MDIS data of the regional survey of the National Agriculture, Forestry and Fishing Survey of the National Statistical Office, and QGIS was used to visualize the status of the elderly, distribution of convenience facilities for the elderly, hot spot maps, and distance analysis, and also technical statistical analysis was conducted. As a result of the analysis, it was confirmed that the distribution and distance of living convenience facilities for the elderly in the area where the elderly lived a lot was located in a location that caused severe inconvenience to the use of the elderly. This suggests the necessity of the change facilities type and spatial reorganization by raising the need for space policy changes on the spatial distribution of elderly convenience facilities, reflecting the serious aging of small towns such as the study area.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.4
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• pp.194-207
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• 2011

This study tries to find the possibility to prevent crime by improving urban spatial environment through the analysis of spatial environment property that mutually coincides or differs by comparing the place where crime actually occurs and the place where citizen is afraid of crime. The method of study is as follows. First, the ontents scope and method of study was established by theoretic investigation of case study related to crime. Second, as crime cannot be prevented by police power only, CPSCP(Citizen Participation System for Crime Prevention) was developed so that all citizen can cooperatively participate in the crime prevention anytime and anywhere. Third, the data on the place where people feel fear in the region was collected by directly indicating the place where citizen is afraid of crime in the space by utilizing CPSCP. Fourth, the place where crime actually occurs and the place where citizen is afraid of crime are redundantly analyzed for comparative analysis of 2 places. The result shows that environmental design improving physical environment of urban space is necessary to prevent crime and to eliminate the fear of crime. The CPSCP developed by this study which will be advanced to U-crime prevention system will contribute to making citizen's own neighborhood a smart safety city autonomously.

• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.187-202
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• 2021

This study examined the effectiveness of wind corridor construction by analyzing the thermal environment, cold air generation, ventilation, and geographical characteristics to improve urban thermal environment and establish the basis for specialized strategy in Changwon-si, Gyeongsangnam-do. Using spatial analysis and remote sensing techniques, surface temperature, land cover and land use, wind field, and slope were measured and through this, a wind corridor analysis model was constructed. As a result of the analysis as of 2020, Changwon-si generally has land cover characteristics that are advantageous for the generation of cold air, but the temperature in most urban areas is the highest, and the temperature in areas such as north Changwon area, Jinbukmyeon, Ung-dong, and Ungcheon-dong are relatively high. There was a typical trend of high average wind speed in mountain regions and low average wind speed in urban areas. Accordingly, the north Changwon area, the former Changwon downtown area, the Hogye-ri and Pyeongseong-ri areas, and the Changpo Bay area are derived as vulnerable areas to thermal environment, and various measures to reduce temperature and improve air quality that the inflow of cold air into the area considering the characteristics of each area and securing wind ventilation between the surrounding mountains, reservoirs, and park areas were proposed.

• Journal of the Korean Geographical Society
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• v.42 no.2 s.119
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• pp.243-257
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• 2007

This paper aims to analyze fear of crime which is considered socio-psychologically important in our daily lives from a geographical point of view. Especially, the spatial patterns of the fear of crime which were analyzed in the area of Youngtong in Suwon city. First, this paper takes a look at the correlation between the incidence of crime and the fear of crime. Most people feel fear in actual crime scenes, but they do not always coincide with place where people feel the high level of fear. Fear of crime is closely connected with physical environments as well as the incidence of crime. The level of fear is high in places where the light is dark, unfrequented paths, especially in parks and around mountains. Several factors which have effects on fear of crime operate differently upon place. Second, a survey which measures the fear of crime was quantitatively analyzed. Factor analysis was employed to find out whether questions are appropriate for measuring the fear of crime as well as to reduce the amount of data so that more exact result can be derived from the data. Through the factor analysis, seven factors were extracted and it is found that a factor of incivility accounts for 24.032% of variance. Other factors which affect fear of crime are community cohesion, warning, incidence of crime, victimization, morality and authority.

• Journal of Forest and Environmental Science
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• v.34 no.6
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• pp.461-471
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• 2018

In this study, the deforestation and forest degradation areas have been obtained in Myanmar using a land cover lamp (LCM) and a tree cover map (TCM) to get the $CO_2$ potential reduction and the strength of occurrence was evaluated by using the geostatistical technique. By applying a multiple criteria decision-making method to the regions having high strength of occurrence for the $CO_2$ potential reduction for the deforestation and forest degradation areas, the priority was selected for candidate lands for REDD+ project. The areas of deforestation and forest degradation were 609,690ha and 43,515ha each from 2010 to 2015. By township, Mong Kung had the highest among the area of deforestation with 3,069ha while Thlangtlang had the highest in the area of forest degradation with 9,213 ha. The number of $CO_2$ potential reduction hotspot areas among the deforestation areas was 15, taking up the $CO_2$ potential reduction of 192,000 ton in average, which is 6 times higher than that of all target areas. Especially, the township of Hsipaw inside the Shan region had a $CO_2$ potential reduction of about 772,000 tons, the largest reduction potential among the hotpot areas. There were many $CO_2$ potential reduction hot spot areas among the forest degradation area in the eastern part of the target region and has the $CO_2$ potential reduction of 1,164,000 tons, which was 27 times higher than that of the total area. AHP importance analysis showed that the topographic characteristic was 0.41 (0.40 for height from surface, 0.29 for the slope and 0.31 for the distance from water area) while the geographical characteristic was 0.59 (0.56 for the distance from road, 0.56 for the distance from settlement area and 0.19 for the distance from Capital). Yawunghwe, Kalaw, and Hsi Hseng were selected as the preferred locations for the REDD+ candidate region for the deforestation area while Einme, Tiddim, and Falam were selected as the preferred locations for the forest degradation area.