• Title/Summary/Keyword: Geographic variation

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Lessons from the Application of GIS for Local Government - Some Examples from Korea and Australia - (지방자치단체에서의 GIS 활용에 대한 제언 - 한국과 호주에서의 사례연구를 중심으로 -)

  • Peterson, Jim;Kim, Chang Hwan;Yoo, Jae Yong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.5 no.3
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    • pp.107-117
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    • 2002
  • Public policy responses to the digital/information revolution and the micro-economic reforms that it facilitates have inspired exploration of the scope for local government implementation of digital spatial data handling(DSDH) of information relating to, among other things, asset inventory, environmental and utility management, address management, and planning. The results from these explorations are such that few doubt the value of bringing the public policies to practice, but diffusion rate and pattern of the approaches demonstrated by the scoping experiments will reflect institutional/cultural matters, indicators of the relative significance of which might be at least partly predicted from appraisal of case studies. This argument is exemplified by reference to case studies in adoption of DSDH by local government organizations in Korea and in Australia.

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A Study on Spatial Statistical Perspective for Analyzing Spatial Phenomena in the Framework of GIS: an Empirical Example using Spatial Scan Statistic for Detecting Spatial Clusters of Breast Cancer Incidents (공간현상 분석을 위한 GIS 기반의 공간통계적 접근방법에 관한 고찰: 공간 군집지역 탐색을 위한 공간검색통계량의 실증적 사례분석)

  • Lee, Gyoung-Ju;Kweon, Ihl
    • Spatial Information Research
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    • v.20 no.1
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    • pp.81-90
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    • 2012
  • When analyzing geographical phenomena, two properties need to be considered. One is the spatial dependence structure and the other is a variation or an uncertainty inhibited in a geographic space. Two problems are encountered due to the properties. Firstly, spatial dependence structure, which is conceptualized as spatial autocorrelation, generates heterogeneous geographic landscape in a spatial process. Secondly, generic statistics, although suitable for dealing with stochastic uncertainty, tacitly ignores location information im plicit in spatial data. GIS is a versatile tool for manipulating locational information, while spatial statistics are suitable for investigating spatial uncertainty. Therefore, integrating spatial statistics to GIS is considered as a plausible strategy for appropriately understanding geographic phenomena of interest. Geographic hot-spot analysis is a key tool for identifying abnormal locations in many domains (e.g., criminology, epidemiology, etc.) and is one of the most prominent applications by utilizing the integration strategy. The article aims at reviewing spatial statistical perspective for analyzing spatial processes in the framework of GIS by carrying out empirical analysis. Illustrated is the analysis procedure of using spatial scan statistic for detecting clusters in the framework of GIS. The empirical analysis targets for identifying spatial clusters of breast cancer incidents in Erie and Niagara counties, New York.

Genetic Diversify and Population Structure of Two Korean Pond Frog Species, Rana nigromaculata and R. plancyi (Anura, Ranidae), with a Survey of Temporal Genetic Variation in R. nigromaculata

  • Suh-Yung Yang;Jong-Bum Kim;Mi-Sook Min;Jae-Hwa Suh
    • Animal cells and systems
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    • v.3 no.3
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    • pp.275-283
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    • 1999
  • Korean R. plancyi occupies a restricted area in western South Korea and shows a relatively low level of genic variability (%P=15.2, Ho=0.052, He=0.048). In contrast, R. nigromaculata is broadly distributed in South Korea. The observed low level of variability of R. nigromaculata (%P=14.3, Ho=0.042, He=0.043) is probably due to its recent colonization. Populations of R. nigromaculata exhibited considerable genetic differentiation (F$_{sT}$=0.149) and low level of gene flow (Nm=1.427) among populations, compared to those of R. Plancyi (F$_{sTF$_{sT}$}$=0.096, Nm=2.354), which occupies a restricted area. The observed levels of gene flow among populations of R. nigromaculata (Nm=1.427) over a broad geographic range is relatively higher than other amphibian species. The high level of gene flow is probably the result of the high dispersal abilities of R. nigromaculata. A survey of temporal genic variation of R. nigromaculata showed that there was no significant change on the overall average genetic diversity from 1978 (average He=0.044) to 1997 (average He=0.040). Wright's F-statistics also indicated no significant genetic differentiation from 1978 (F$_{sT}$=0.118) to 1997 (F$_{sT}$=0.108). This suggests that the environmental change appears to have had little influence on the genetic composition of R. nigromaculata in the study areas during the past 20 years. The low level of temporal variation might be due to the result of high dispersal abilities and wide migration range of this species.

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Morphological Variation of Two Cultivated Types of Perilla Crop from Different Areas of China

  • Ma, Shi Jun;Lee, Ju Kyong
    • Horticultural Science & Technology
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    • v.35 no.4
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    • pp.510-522
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    • 2017
  • To better understand the morphological variation for Perilla crop in different areas of China, we studied the morphological variation in 87 accessions (84 cultivated var. frutescens and three cultivated var. crispa) from high latitude (Northeast China) and middle latitude (North and Northwest China) areas of China by examining seven quantitative and 10 qualitative characters. Analysis of the morphological variation determined that there was significant morphological differences in five quantitative traits between cultivated var. frutescens and cultivated var. crispa, including effective number of branches (QN2), number of internodes (QN3), number of branches (QN4), length of the largest inflorescence (QN5), and days from germination to flowering (QN7). However, two quantitative traits-plant height and number of florets of the largest inflorescence-did not show any significant differences between cultivated var. frutescens and cultivated var. crispa. In addition, significant differences for six quantitative traits were found between the accessions of cultivated var. frutescens originating from high and middle latitude areas in China, which included QN2, QN3, QN5, number of florets of the largest inflorescence (QN6), and QN7. Principal components analysis (PCA) identified five quantitative characters [plant height (QN1), QN2, QN3, QN4, QN7] and six qualitative characters [fragrance of plant (QL1), color of reverse side of leaf (QL3), degree of pubescence (QL5), color of flower (QL6), shape of leaf (QL7), and hardness of seed (QL10)] that contributed to the positive direction on the first axis. The other quantitative and qualitative characters contributed to the negative direction on the first axis. Most accessions of cultivated var. frutescens and cultivated var. crispa were clearly separated by the first axis. In addition, most accessions of cultivated var. frutescens are from high latitude and middle latitude areas that were clearly separated by the first axis, except for several accessions. The findings from this study will provide useful information towards understanding the morphological variation of Perilla crop according to geographical distribution in high and middle latitude regions of China.

Genetic Variation of Taenia Pisiformis Collected from Sichuan, China, Based on the Mitochondrial Cytochrome b gene

  • Yang, Deying;Ren, Yongjun;Fu, Yan;Xie, Yue;Nie, Huaming;Nong, Xiang;Gu, Xiaobin;Wang, Shuxian;Peng, Xuerong;Yang, Guangyou
    • Parasites, Hosts and Diseases
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    • v.51 no.4
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    • pp.449-452
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    • 2013
  • Taenia pisiformis is one of the most important parasites of canines and rabbits. T. pisiformis cysticercus (the larval stage) causes severe damage to rabbit breeding, which results in huge economic losses. In this study, the genetic variation of T. pisiformis was determined in Sichuan Province, China. Fragments of the mitochondrial cytochrome b (cytb) (922 bp) gene were amplified in 53 isolates from 8 regions of T. pisiformis. Overall, 12 haplotypes were found in these 53 cytb sequences. Molecular genetic variations showed 98.4% genetic variation derived from intra-region. $F_{ST}$ and Nm values suggested that 53 isolates were not genetically differentiated and had low levels of genetic diversity. Neutrality indices of the cytb sequences showed the evolution of T. pisiformis followed a neutral mode. Phylogenetic analysis revealed no correlation between phylogeny and geographic distribution. These findings indicate that 53 isolates of T. pisiformis keep a low genetic variation, which provide useful knowledge for monitoring changes in parasite populations for future control strategies.

Two-dimensional Inundation Analysis Using Stochastic Rainfall Variation and Geographic Information System (추계학적 강우변동생성 기법과 GIS를 연계한 2차원 침수해석)

  • Lee, Jin-Young;Cho, Wan-Hee;Han, Kun-Yeun;Ahn, Ki-Hong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.1
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    • pp.101-113
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    • 2010
  • Recently actual rainfall pattern is decreasing rainy days and increasing in rainfall intensity and the frequency of flood occurrence is also increased. To consider recent situation, Engineers use deterministic methods like a PMP(Probable Maximum Precipitation). If design storm wouldn't occur, increasing of design criteria is extravagant. In addition, the biggest structure cause trouble with residents and environmental problem. And then it is necessary to study considering probability of rainfall parameter in each sub-basin for design of water structure. In this study, stochastic rainfall patterns are generated by using log-ratio method, Johnson system and multivariate Monte Carlo simulation. Using the stochastic rainfall patterns, hydrological analysis, hydraulic analysis and 2nd flooding analysis were performed based on GIS for their applicability. The results of simulations are similar to the actual damage area so the methodology of this study should be used about making a flood risk map or regidental shunting rout map against the region.

Development of Severity-Adjustment Model for Length of Stay in Hospital for Percutaneous Coronary Interventions (관상동맥중재술 환자의 재원일수 중증도 보정 모형 개발)

  • Nam, Mun-Hee;Kang, Sung-Hong;Lim, Ji-Hye
    • The Journal of the Korea Contents Association
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    • v.11 no.9
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    • pp.372-383
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    • 2011
  • Our study was carried out to develop the severity-adjustment model for length of stay in hospital for percutaneous coronary interventions so that we would analysis the factors on the variation in length of stay(LOS). The subjects were 1,011 percutaneous coronary interventions inpatients of the Korean National Hospital Discharge In-depth Injury Survey 2004-2006 data. The data were analyzed using t-test and ANOVA and the severity-adjustment model was developed using data mining technique. After yielding the standardized value of the difference between crude and expected length of stay, we analysed the variation of length of stay for percutaneous coronary interventions. There was variation of LOS in regional differences, size of sickbed and insurance type. The variation of length of stay controlling the case mix or severity of illness can be explained the factors of provider. This supply factors in LOS variations should be more studied for individual practice style or patient management practices and healthcare resources or environment. We expect that the severity-adjustment model using administrative databases should be more adapted in other diseases in practical.

Population Genetic Structure of Potentilla discolor Bunge, Rosaceae in Korea (한국내 솜양지꽃의 집단 유전 구조)

  • Huh, Man-Kyu
    • Journal of Life Science
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    • v.16 no.6
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    • pp.898-903
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    • 2006
  • The genetic diversity and population structure of fifteen Potentilla discolor Bunge populations in Korea were determined using genetic variations at 19 allozyme loci. Fourteen of the 19 loci (73.7%) showed detectable polymorphism. Genetic diversity at the species level and at the population level was high ($H_{ES}\;=\;0.215$, $H_{EP}\;=\;0.196$, respectively), whereas the extent of the population divergence was relatively low $(G_{ST}\;=\;0.069)$. Total genetic diversity values $(H_T)$ varied between 0.0 and 0.656, giving an average overall polymorphic loci of 0.292. The interlocus variation of genetic diversity within populations $(H_S)$ was high (0.274). On a per locus basis, the proportion of total genetic variation due to differences among populations $(G_{ST})$ ranged from 0.010 for Pgm-2 to 0.261 for Pgd-2 with a mean of 0.069, indicating that about 6.9% of the total allozyme variation was among populations. Wide geographic ranges, perennial herbaceous nature and the persistence of multiple generations are associated with the high level of genetic variation in P. discolor. The estimate of gene flow based on $G_{ST}$ was high among Korean populations of P. discolor (Nm = 3.36).

Genetic Variation in the Natural Populations of Korean Stewartia (Stewartia koreana Nakai) Based on I-SSR Analysis (I-SSR 분석에 의한 노각나무 천연집단의 유전변이)

  • Yang Byeung-Hoon;Koo Yeong-Bon;Park Yong-Goo;Han Sang-Don
    • Korean Journal of Plant Resources
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    • v.19 no.1
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    • pp.189-195
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    • 2006
  • We investigated the genetic variation in Stewartia koreana Nakai by examining 61 I-SSR amplicons in 120 individuals distributed among six natural populations in Korea. The overall percentage of polymorphic I-SSR amplicons was 81.9% and mean number of amplicons per I-SSR primer was 12.2. Levels of genetic diversity within 6 populations were similar each other[Shannon's Index $0.358{\sim}0.467$(mean: 0.407)]. The Mt. Obong population had the highest level of genetic diversity and was most distinctive from the other populations. Most variation existed among individuals within population(88.2%). Genetic differentiation among populations(${\phi}_{ST}$) was 0.118. The UPGMA dendrogram based on the genetic distance failed in showing decisive geographic relationships.

Genetic Diversity and Population Structure of Potentilla freyniana in Korea (한국내 세잎양지꽃의 유전적 다양성과 집단구조)

  • Huh, Man-Kyu
    • Journal of Life Science
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    • v.17 no.7 s.87
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    • pp.877-881
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    • 2007
  • The genetic diversity and population structure of Potentilla freyniana in Korea were determined using genetic variations at 19 allozyme loci. Thirteen of the 19 loci (68.4%) showed detectable polymorphism. Genetic diversity at the population level was high ($H_{EP}$ = 0.270). Total genetic diversity values ($H_T$) varied between 0.190 and 0.584, giving an average overall polymorphic loci of 0.371. The interlocus variation of genetic diversity within populations ($H_S$) was high (0.354). On a per locus basis, the proportion of total genetic variation due to differences among populations ($G_{ST}$) ranged from 0.008 for Fe-2 to 0.310 for Gpi with a mean of 0.065, indicating that about 6.5% of the total allozyme variation was among populations. Wide geographic ranges, perennial herbaceous nature and the persistence of multiple generations are associated with the high level of genetic variation in P. freyniana. The estimate of gene flow based on $G_{ST}$, was high among Korean populations of P. freyniana (Nm =3.57). Although P. freyniana usually propagated by asexually-produced ramets, I could not rule out the possibility that sexual reproduction occurred at a low rate because each ramet may produce terminal flowers.