• Title/Summary/Keyword: Geographic locations

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Application of GIS to the Universal Soil Loss Equation for Quantifying Rainfall Erosion in Forest Watersheds (산림유역의 토양유실량(土壤流失量) 예측을 위한 지리정보(地理情報)시스템의 범용토양유실식(汎用土壤流失式)(USLE)에의 적용)

  • Lee, Kyu Sung
    • Journal of Korean Society of Forest Science
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    • v.83 no.3
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    • pp.322-330
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    • 1994
  • The Universal Soil Loss Equation (USLE) has been widely used to predict long-term soil loss by incorporating several erosion factors, such as rainfall, soil, topography, and vegetation. This study is aimed to introduce the LISLE within geographic information system(GIS) environment. The Kwangneung Experimental Forest located in Kyongki Province was selected for the study area. Initially, twelve years of hourly rainfall records that were collected from 1982 to 1993 were processed to obtain the rainfall factor(R) value for the LISLE calculation. Soil survey map and topographic map of the study area were digitized and subsequent input values(K, L, S factors) were derived. The cover type and management factor (C) values were obtained from the classification of Landsat Thematic Mapper(CM) satellite imagery. All these input values were geographically registered over a common map coordinate with $25{\times}25m^2$ ground resolution. The USLE was calculated for every grid location by selecting necessary input values from the digital base maps. Once the LISLE was calculated, the resultant soil loss values(A) were represented by both numerical values and map format. Using GIS to run the LISLE, it is possible to pent out the exact locations where soil loss potential is high. In addition, this approach can be a very effective tool to monitor possible soil loss hazard under the situations of forest changes, such as conversion of forest lands to other uses, forest road construction, timber harvesting, and forest damages caused by fire, insect, and diseases.

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Phylogenetic Analysis of env Gene V3-V5 Region of HIV-1 Subtype A Isolates from Korean (한국인 HIV 감염자에서 분리된 HIV-1 Subtype A의 env 유전자 V3-V5 부위의 계통적 분석)

  • Lee, Joo-Shil;Kim, Eun-Young;Kang, Chun;Nam, Jeong-Gu;Lee, Sung-Rae;Koo, Bon-Ki;Shin, Yung-Oh
    • The Journal of Korean Society of Virology
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    • v.29 no.2
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    • pp.119-127
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    • 1999
  • Phylogenetic analysis was conducted to monitor transmission of HIV and to investigate the genetic structure of primary isolates from 12 HIV-1 subtype A infected Koreans. The individuals infected with subtype A viruses had been diagnosed as HIV-1 seropositives during the period 1987 to 1995 and blood samples have been collected from 1991 to 1997. DNA of each individual was isolated from uncultured or cultured peripheral blood mononuclear cells. V3-V5 (0.7 kb) fragment of HIV-1 env gene was amplified by nested polymerase chain reaction and the PCR products were sequenced. The mean value of the divergence of nucleotide of HIV-1 env V3-V5 fragment was $17.0{\pm}4.06%$ ($8.6{\sim}25.8%$) within HIV-1 subtype A isolates from Koreans. This diversity was higher than those of African isolates ($13.7{\pm}2.66%$). In the phylogenetic tree, Korean subtype A isolates were not grouped together, but intermingled into African isolates. The results of this study suggested that HIV-1 subtype A variants be introduced from multiple sites of Africa into Korea and the big genetic diversity of Korea HIV-1 subtype A isolates may be further influenced by the range of geographic locations in which the infection occurred rather than the elapsed time between infection and collection of samples and the disease progression.

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Estimation of Climatological Precipitation of North Korea by Using a Spatial Interpolation Scheme (지형기후학적 공간내삽에 의한 북한지역 강수기후도 작성)

  • Yun Jin-Il
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.2 no.1
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    • pp.16-23
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    • 2000
  • A topography-precipitation relationship derived from the southern part of Korean Peninsula was applied to North Korea where climate stations are few and widely separated. Two hundred and seventy seven rain gauge stations of South Korea were classified into 8 different groups depending on the slope orientation (aspect) of the region they are located. Monthly precipitation averaged over 10 year period (1986-1995) was regressed to topographical variables of the station locations. A 'trend precipitation' for each gauge station was extracted from the precipitation surface interpolated from the monthly precipitation data of 24 standard stations of the Korea Meteorological Administration and used as a substitute for y-axis intercept of the regression equation. These regression models were applied to the corresponding regions of North Korea, which were identified by slope orientation, to obtain monthly precipitation surface for the aspect regions. 'Trend precipitation' from the 10 year data of 27 North Korean standard stations was also used in the model calculation. Output grids for each aspect region were mosaicked to form the monthly and annual precipitation surface with a 1km$\times$1km resolution for the entire territory of North Korea. Spatially averaged annual precipitation of North Korea was 938 mm with the standard deviation of 246 mm.

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k-Interest Places Search Algorithm for Location Search Map Service (위치 검색 지도 서비스를 위한 k관심지역 검색 기법)

  • Cho, Sunghwan;Lee, Gyoungju;Yu, Kiyun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.4
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    • pp.259-267
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    • 2013
  • GIS-based web map service is all the more accessible to the public. Among others, location query services are most frequently utilized, which are currently restricted to only one keyword search. Although there increases the demand for the service for querying multiple keywords corresponding to sequential activities(banking, having lunch, watching movie, and other activities) in various locations POI, such service is yet to be provided. The objective of the paper is to develop the k-IPS algorithm for quickly and accurately querying multiple POIs that internet users input and locating the search outcomes on a web map. The algorithm is developed by utilizing hierarchical tree structure of $R^*$-tree indexing technique to produce overlapped geometric regions. By using recursive $R^*$-tree index based spatial join process, the performance of the current spatial join operation was improved. The performance of the algorithm is tested by applying 2, 3, and 4 multiple POIs for spatial query selected from 159 keyword set. About 90% of the test outcomes are produced within 0.1 second. The algorithm proposed in this paper is expected to be utilized for providing a variety of location-based query services, of which demand increases to conveniently support for citizens' daily activities.

Quantitative Analysis of the Periodicity of Dirofilaria immitis in Dogs with Various Microfilarial Densities (개심장사상충의 정기 출현성에 관한 정량적 분석)

  • Park Son-Il;Lee Hong-soo;Ahn So-jeo;Jeoung Seok-young;Kim Doo
    • Journal of Veterinary Clinics
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    • v.22 no.2
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    • pp.79-83
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    • 2005
  • Six dogs including 4 dogs living in different geographic locations of Kangwon province and 2 client-owned dogs were used to determine the periodicity of microfilariae of D. immitis using a trigonometric model. The calculated periodicity index was ranged from 25.6 to $95.5\%$ with mean of $57.6\%$, and the estimated hour of peak was approximately 21:00 hrs (range, 20:04-21:29 hrs) and minimum counts at 09:00 hrs (range, 08:04 - 09:29 hrs). Correlation coefficient between the observed and the expected count from the model varies depending on dogs, ranging from 6.4 to $49.2\%$. Based on this study, the periodicity of microfilariae of D. immitis was considered as nocturnally sub-periodic for all dogs employed. This result is in consistent with previous report in peak hour but different in minimal hour, indicating that further studies on the periodicity need to be performed to better understanding the dynamics of the periodicity and to help practitioners in the choice of the time for examination of the dogs.

Behavior of Nutrients along the Salinity Gradients in the Seomjin River Estuary (섬진강 하구역에서 염분경사에 따른 영양염의 거동)

  • KWON Kee-Young;MOON Chang-Ho;YANG Han-Seob
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.3
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    • pp.199-206
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    • 2001
  • Behavior of nutrients along the salinity gradients in the Seomjin River estuary was investigated in March July, September and November, 1999. Sampling sites were set based on the surface salinity during each cruise rather than geographic locations. The results suggest that source of nitrate and silicate was the Seomjin River discharge, while that of nitrite and phosphate was waste disposal from the Gwangynng Bay near the mouth of Seomjin River estuary. Ammonia was supplied inside the estuary at the region about $6\~8$ km far from Nancho Island. Strong removal behavior of some nutrient such as ammonia, phosphate and silicate was observed at $5\~15$ psu salinity area in November, where high concentrations of $chlorophyll\;a\;(>8{\mu}g/L$) occurred. High N : P ratios and entirely removal of phosphate at chlorophyll a peak region suggest that phosphate is the limiting factor for phytoplankton growth. Relatively high ratios of Rb to Ra (Rb: Fluorescence before acidification, Ra: Fluorescence after acidification) at $5\~15$ psu salinity region in November indicate that phytoplankton were in good physiological condition.

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Spatial Location Modeling for the Efficient Placements of the Super WiFi Facilities Utilizing White Spaces (화이트 스페이스를 활용한 슈퍼 와이파이 시설의 효율적 배치를 위한 공간 입지 모델링)

  • Lee, Gunhak;Kim, Kamyoung
    • Journal of the Korean Geographical Society
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    • v.48 no.2
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    • pp.259-271
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    • 2013
  • This paper addresses the efficient facility placements to adopt a super WiFi network, taking significant considerations as the next generation 'information highway'. Since the super WiFi has a wider geographic coverage by utilizing the white spaces of TV broadcasting which are empty and available frequencies for the wireless communications, it would play an important role in releasing digital divide of the internet access for low populated or mountainous areas. The purpose of this paper is to explore systematic and efficient spatial plans for the super WiFi. For doing this, we applied optimal location covering models to Gurye-gun, Jeonlanamdo. From the application, we presented optimal locations for super WiFi facilities and significant analytical results, such as the tradeoff between the number of facilities and coverage and marginal coverage for establishing super WiFi network. The results of this research would be usefully utilized for decision makers who wish to adopt a super WiFi, to extend wireless networks in a city or build a regional infrastructure of wireless facilities.

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The Analysis of Spatial Distribution of Gifted Education Units in Seoul (서울시 영재교육기관의 공간적 분포특성 분석)

  • Kim, Sungyeun;Lee, Seon-Young
    • Journal of Gifted/Talented Education
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    • v.25 no.5
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    • pp.711-729
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    • 2015
  • The purposes of this study are to derive the regions in Seoul that lack gifted education units by analyzing the spatial distribution of the units and to investigate the factors related to the unit locations. The gifted education units are divided into the three following types: the first type is a gifted class at a school, the second type is a gifted education center at a provincial office of education, and the third type is a gifted education center at a university. The results of using a GIS-based spatial analysis were as follows. First, a buffering analysis showed that even though there were gifted educational blind spots in Jongno-gu and in parts of the outskirts of Seoul, the spatial distribution of gifted education units in Seoul seemed homogeneous because they were too small. Second, a special quotient analysis showed that there was a hub unit of gifted education in Guro-gu. Third, an analysis of local Moran's Index showed that Jung-gu was a cold spot and Songa-gu was a hot spot. Fourth, a correlation analysis investigated that the number of gifted education units had generally no statistically significant relationship with economic factors. These results will help to improve the efficiency and equity of the management of the gifted education units in Seoul that will be established or expanded in the future.

Study on Developing Program for Efficient Landscape Woody Plants Management - Mainly Focused on the Development of a Tree Inventory System - (조경수목의 효율적 관리를 위한 프로그램 개발에 관한 연구 - 관리대장(Tree Inventory) 개발을 중심으로 -)

  • 조영환;곽행구
    • Journal of the Korean Institute of Landscape Architecture
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    • v.24 no.4
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    • pp.1-22
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    • 1997
  • This paper was focused on the efficient management of landscape woody plants, and concerned itself with their important role in the urban environment. Based on the philosophy that there is nothing that can be done without an inventory, the purpose of this study was to develop an inventory system and iris proper application to a site for establishing a management plan Two different approaches were used, The first was to make a newly structured inventory system through collecting, analyzing, and evaluating various types of inventories used in Korea, the U. S. A., and Japan. The second approach was to apply a newly designed inventory system to the case study area. using GIS 'as a tool of spacial analysis and statistics for making decisions. The results could be summarized as follows; 1. In Korea, most of the Landscape Woozy Plants Inventories had datas which represented possession of trees, and only the work which they had done according to their traditional ways, There was no data related to the conditions, management needs, and site conditions of individual trees, This is essential information for organizing an inventory system . 2. There needs to be data which is balanced, containing tree characteristics and site characteristics. Through such information the management needs could be adjusted properly. The inventory list described in this paper was determined by botanical identity, placement condition, condition of tree, and types of work for maintaining as well as improving the condition of each tree One of the most important things was to determine the location data of each tree so as to compare data with other trees. The data gained from the field survey still had some problems because of lack of scientific method for supporting objective views, and because of actual situations, especially in the field of evaluating site conditions and management needs. All data should be revised to fit a computer data management system , if possible 3. The GIS(Geographic Information System) application showed good performance in handling inventory data for decision making. All the data used for the GIS application was divided into location and non-spatial data. Using the location data, it was easy to find the exact location of each tree on the monitor and on the maps generated by the computer even in the actual managed trite, along with various attribute data. Therefore it could be said that the entire management plan should start from data of individual trees with their exact locations, for making concrete management goals through actual budget planning.

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Associations between Exposure to Unhealthy Food Outlets Within Residential District and Obesity: Using Data from 2013 Census on Establishments and 2013-2014 Korea National Health and Nutrition Examination Survey (거주지 주변의 식품환경과 비만의 관련성 연구: 2013 전국사업체조사와 2013-2014 국민건강영양조사 자료를 이용하여)

  • Kim, Yoonjung;Han, Sung Nim
    • Korean Journal of Community Nutrition
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    • v.21 no.5
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    • pp.463-476
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    • 2016
  • Objectives: Environmental, social and personal factors influence eating patterns. This study aimed to investigate the relationship between unhealthy food outlets within a residential area and obesity using nationally representative Korean survey data and data from the Census on Establishments. Methods: Data on the food intakes and socioeconomic variables of a total of 9,978 adults aged ${\geq}19$ years were obtained from the 2013-2014 Korea National Health and Nutrition Examination Survey. Geographic locations of restaurants were obtained from the 2013 Census on Establishments in Korea. Administrative area was categorized into tertiles of count of unhealthy food outlets based on the distribution of number of unhealthy food outlets among all urban (Dong) and rural (Eup or Myun) administrative districts in Korea. Multilevel logistic regressions model were used to assess the association between the number of unhealthy food outlets and obesity. Results: People living in the district with the highest count of unhealthy food outlets had higher intakes of fat (45.8 vs. 44.4 g/day), sodium (4,142.6 vs. 3,949.8 mg/day), and vitamin A (753.7 vs. $631.6 {\mu}gRE/day$) compared to those living in the district with the lowest count of unhealthy food outlets. A higher count of unhealthy food outlets was positively associated with frequent consumption of instant noodles, pizza, hamburgers and sandwiches, sweets and sour pork or pork cutlets, fried chicken, snacks, and cookies. Higher exposure to unhealthy food outlets was associated with increased odds of obesity (1st vs. 3rd tertile; OR 1.689; 95% CI 1.098-2.599). Conclusions: A high count of unhealthy food outlets within a residential area is positively associated with the prevalence of obesity in Korea. The results suggest that food environmental factors affects the health outcomes and interventions aiming to restrict the availability of unhealthy food outlets in local neighborhoods may be a useful obesity prevention strategy.