• Title/Summary/Keyword: SPATIAL SCALE

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Spatial Autocorrelation Analysis among Subpopulations of Salix koriyanagi in Swampy Area at the Namgang River, Korea (남강 습지에 분포하는 키버들 집단의 공간적 상관 분석)

  • Huh, Man-Kyu
    • Journal of Life Science
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    • v.18 no.10
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    • pp.1325-1330
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    • 2008
  • Salix koriyanagi is a deciduous shrub and native to Korea. The spatial distribution of multilocus allelic frequencies and geographical distances of the natural population in upper swampy area at the Namgang River in Korea were studied. The species showed a significant positive and negative spatial autocorrelation according to geographical distances as measured by Moran's I. Genetic similarity of individuals was found among subpopulations at up to a scale of a 12 m distance, and this was partly due to a combination of allelic frequencies, and therefore, a significant spatial autocorrelation was composed of a scale of 12 m intervals. Within S. koriyanagi in swampy area at the Namgang River, a strong spatial structure was observed for allozyme markers, indicating a migration within subpopulations.

Spatial Autocorrelation Analysis among Subpopulations of Salix koriyanagi in Swampy Area at the Namgang River, Korea (남강 습지에 분포하는 키버들 집단의 공간적 상관 분석)

  • Huh, Man-Kyu
    • Journal of Life Science
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    • v.18 no.11
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    • pp.1465-1470
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    • 2008
  • Salix koriyanagi is a deciduous shrub and native to Korea. The spatial distribution of multilocus allelic frequencies and geographical distances of the natural population in upper swampy area at the Namgang River in Korea were studied. The species showed a significant positive and negative spatial autocorrelation according to geographical distances as measured by Moran's I. Genetic similarity of individuals was found among subpopulations at up to a scale of a 12 m distance, and this was partly due to a combination of allelic frequencies, and therefore, a significant spatial autocorrelation was composed of a scale of 12 m intervals. Within S. koriyanagi in swampy area at the Namgang River, a strong spatial structure was observed for allozyme markers, indicating a migration within subpopulations.

Evaluation of Biodiversity Based on Changes of Spatial Scale -A Case Study of Baekdudaegan Area in Kangwondo- (공간스케일 변화에 따른 생물다양성 평가 -강원도 백두대간 보호구역을 대상으로-)

  • Sim, Woodam;Park, Jinwoo;Lee, Jungsoo
    • Journal of Forest and Environmental Science
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    • v.30 no.1
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    • pp.91-100
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    • 2014
  • This research was conducted on the conservation area of Baekdudaegan, Kangwondo under the purpose of evaluating bio-diversity according to the changes of spatial scale, using GIS data and spatial filtering method. The diversity index was calculated based on the information of species of The $5^{th}$ forest type map using Shannon-weaver index (H'), evenness index ($E_i$) and richness index ($R_i$). The diversity index was analyzed and compared according to the changes of 12 spatial scales from Kernel size $3{\times}3$ to $73{\times}73$ and basin unit. As for H' and $R_i$, spatial scale increased as diversity index decreased, while $E_i$ decreases gradually. H' and $R_i$ was highest; each 1.1 and 0.6, when the Kernel size was $73{\times}73$, while $E_i$ was 0.2, the lowest. When you look at according to the basin unit, for large basin unit, 'YeongDong' region shows higher diversity index than 'YeongSeo' region. For middle basin unit, 'Gangneung Namdaecheon' region, and for small basin unit, 'Gangneung Namdaecheon' and 'Gangneung Ohbongdaem' region shows high diversity index. When you look at the relationship between diversity index and Geographic factors, H' shows positive relation to curvature and sunshine factor while shows negative to elevation, slope, hillshade, and wetness index. Also $E_i$ was similar to the relationship between H' and Geographic factor. Meanwhile, $R_i$ shows positive relationship to curvature and sunshine factor, while negative to elevation, slope, hillshade, and wetness index. macro unit diversity index evaluation was possible through the GIS data and spatial filtering, and it can be a good source for local biosphere conservation policy making.

A Study on the Sensibility Evaluation Criteria of a Spatial Environment - Focusing on an interior spatial environment - (공간환경의 감성평가척도에 관한 연구 - 인테리어 공간 환경을 중심으로 -)

  • Han, Myoung-Heum;Oh, In-Wook
    • Korean Institute of Interior Design Journal
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    • v.19 no.4
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    • pp.3-10
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    • 2010
  • The purpose of this study is to select and analyze words that represent various emotional states towards a spatial environment. Selecting appropriate words for the sensibility evaluation of a spatial environment is a process of constructing sensibility indicators, so that an accurate selection of sensibility words is very important. To collect basic words for this study, words for expressing sensation, emotional states, and sensibility regarding a spatial environment have been collected first via free association and a literature review of previous studies. In the second stage, the selected words are refined. Fifteen evaluators have participated in the first process of refining words, 140 college students participated in the second process, and than the final list of 277 refined words has been selected. During the third stage, 15 specialists were asked to evaluate the appropriateness of sensibility evaluation words, for that 7 point-scale has been applied. Then, 99 words with an average point of 4.55 or more and a standard deviation of 1.55 or lower were selected. After investigating the similarity in the meanings of the selected words, 55 pairs of contrasting words have been selected as a final list of sensibility evaluation words. During this last stage, 307 college students majoring in related fields were asked to evaluate the appropriateness of sensibility evaluation words for a spatial environment, and 7 point-scale was obtained. A factor analysis, cluster analysis, and multidimensional analysis have been conducted on the data obtained from these survey. According to the results of the factor analysis, the eight important factors are obtained from the sensibility evaluation criteria of a spatial environment(form, texture, function, value, comfort, aesthetics, atmosphere, and affinity). The factors obtained from this study can be used in the beginning stage of evaluating the sensibility factors of a spatial environment. In addition, the results of this study can be used as basic data when constructing a list of evaluation indicators to select various complex sensibility words for a space; or as general indicators when evaluating various spatial design factors.

Design and Implementation of a Large-Scale Spatial Reasoner Using MapReduce Framework (맵리듀스 프레임워크를 이용한 대용량 공간 추론기의 설계 및 구현)

  • Nam, Sang Ha;Kim, In Cheol
    • KIPS Transactions on Software and Data Engineering
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    • v.3 no.10
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    • pp.397-406
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    • 2014
  • In order to answer the questions successfully on behalf of the human in DeepQA environments such as Jeopardy! of the American quiz show, the computer is required to have the capability of fast temporal and spatial reasoning on a large-scale commonsense knowledge base. In this paper, we present a scalable spatial reasoning algorithm for deriving efficiently new directional and topological relations using the MapReduce framework, one of well-known parallel distributed computing environments. The proposed reasoning algorithm assumes as input a large-scale spatial knowledge base including CSD-9 directional relations and RCC-8 topological relations. To infer new directional and topological relations from the given spatial knowledge base, it performs the cross-consistency checks as well as the path-consistency checks on the knowledge base. To maximize the parallelism of reasoning computations according to the principle of the MapReduce framework, we design the algorithm to partition effectively the large knowledge base into smaller ones and distribute them over multiple computing nodes at the map phase. And then, at the reduce phase, the algorithm infers the new knowledge from distributed spatial knowledge bases. Through experiments performed on the sample knowledge base with the MapReduce-based implementation of our algorithm, we proved the high performance of our large-scale spatial reasoner.

Optimal Spatial Scale for Land Use Change Modelling : A Case Study in a Savanna Landscape in Northern Ghana (지표피복변화 연구에서 최적의 공간스케일의 문제 : 가나 북부지역의 사바나 지역을 사례로)

  • Nick van de Giesen;Paul L. G. Vlek;Park Soo Jin
    • Journal of the Korean Geographical Society
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    • v.40 no.2 s.107
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    • pp.221-241
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    • 2005
  • Land Use and Land Cover Changes (LUCC) occur over a wide range of space and time scales, and involve complex natural, socio-economic, and institutional processes. Therefore, modelling and predicting LUCC demands an understanding of how various measured properties behave when considered at different scales. Understanding spatial and temporal variability of driving forces and constraints on LUCC is central to understanding the scaling issues. This paper aims to 1) assess the heterogeneity of land cover change processes over the landscape in northern Ghana, where intensification of agricultural activities has been the dominant land cover change process during the past 15 years, 2) characterise dominant land cover change mechanisms for various spatial scales, and 3) identify the optimal spatial scale for LUCC modelling in a savanna landscape. A multivariate statistical method was first applied to identify land cover change intensity (LCCI), using four time-sequenced NDVI images derived from LANDSAT scenes. Three proxy land use change predictors: distance from roads, distance from surface water bodies, and a terrain characterisation index, were regressed against the LCCI using a multi-scale hierarchical adaptive model to identify scale dependency and spatial heterogeneity of LUCC processes. High spatial associations between the LCCI and land use change predictors were mostly limited to moving windows smaller than 10$\times$10km. With increasing window size, LUCC processes within the window tend to be too diverse to establish clear trends, because changes in one part of the window are compensated elsewhere. This results in a reduced correlation between LCCI and land use change predictors at a coarser spatial extent. The spatial coverage of 5-l0km is incidentally equivalent to a village or community area in the study region. In order to reduce spatial variability of land use change processes for regional or national level LUCC modelling, we suggest that the village level is the optimal spatial investigation unit in this savanna landscape.

The Development Process and Spatial Characteristics of Sino-South Korean Cross-border Small-scale Trade (한.중 소무역의 변화 과정과 공간적 특성)

  • Jang, Young-Jin
    • Journal of the Korean Geographical Society
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    • v.45 no.5
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    • pp.628-646
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    • 2010
  • The subject of this research is the small-scale trade between South Korea and China (this trade is a so-called shuttle trade.) This research attempts to find the background to the emergence of the Sino-South Korean (cross-border) small-scale trade and the role of travel routes between the two countries. This research also aims to identify the development process of the bilateral small-scale trade by studying the scale of the small-scale trade and the organization of small-scale traders. Moreover, this research tries to discover the spatial characteristics of the interregional small-scale trade by reviewing the characteristics of traded goods; process of export and import and nodes of small-scale trade. To accomplish aforementioned purposes, the author discussed the relations between small-scale traders and maritime companies. The author also studied the internal change in the small-scale trade by focusing on the reinforcement of the regulation against the small-scale trade. Lastly, the author cited the case of the Soviet Union and middle-eastern Europe, which tremendously expanded the small-scale trades in the 1980s, in order to explain the growth of the Sino-South Korean small-scale trade.

Spatial Analyses and Modeling of Landsacpe Dynamics (지표면 변화 탐색 및 예측 시스템을 위한 공간 모형)

  • 정명희;윤의중
    • Spatial Information Research
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    • v.11 no.3
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    • pp.227-240
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    • 2003
  • The primary focus of this study is to provide a general methodology which can be utilized to understand and analyze environmental issues such as long term ecosystem dynamics and land use/cover change by development of 2D dynamic landscape models and model-based simulation. Change processes in land cover and ecosystem function can be understood in terms of the spatial and temporal distribution of land cover resources. In development of a system to understand major processes of change and obtain predictive information, first of all, spatial heterogeneity is to be taken into account because landscape spatial pattern affects on land cover change and interaction between different land cover types. Therefore, the relationship between pattern and processes is to be included in the research. Landscape modeling requires different approach depending on the definition, assumption, and rules employed for mechanism behind the processes such as spatial event process, land degradation, deforestration, desertification, and change in an urban environment. The rule-based models are described in the paper for land cover change by natural fires. Finally, a case study is presented as an example using spatial modeling and simulation to study and synthesize patterns and processes at different scales ranging from fine-scale to global scale.

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Residual spatial autocorrelation in macroecological and biogeographical modeling: a review

  • Gaspard, Guetchine;Kim, Daehyun;Chun, Yongwan
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.191-201
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    • 2019
  • Macroecologists and biogeographers continue to predict the distribution of species across space based on the relationship between biotic processes and environmental variables. This approach uses data related to, for example, species abundance or presence/absence, climate, geomorphology, and soils. Researchers have acknowledged in their statistical analyses the importance of accounting for the effects of spatial autocorrelation (SAC), which indicates a degree of dependence between pairs of nearby observations. It has been agreed that residual spatial autocorrelation (rSAC) can have a substantial impact on modeling processes and inferences. However, more attention should be paid to the sources of rSAC and the degree to which rSAC becomes problematic. Here, we review previous studies to identify diverse factors that potentially induce the presence of rSAC in macroecological and biogeographical models. Furthermore, an emphasis is put on the quantification of rSAC by seeking to unveil the magnitude to which the presence of SAC in model residuals becomes detrimental to the modeling process. It turned out that five categories of factors can drive the presence of SAC in model residuals: ecological data and processes, scale and distance, missing variables, sampling design, and assumptions and methodological approaches. Additionally, we noted that more explicit and elaborated discussion of rSAC should be presented in species distribution modeling. Future investigations involving the quantification of rSAC are recommended in order to understand when rSAC can have an adverse effect on the modeling process.