• Title/Summary/Keyword: Spatial point pattern analysis

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Spatial distribution patterns of old-growth forest of dioecious tree Torreya nucifera in rocky Gotjawal terrain of Jeju Island, South Korea

  • Shin, Sookyung;Lee, Sang Gil;Kang, Hyesoon
    • Journal of Ecology and Environment
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    • v.41 no.8
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    • pp.223-234
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    • 2017
  • Background: Spatial structure of plants in a population reflects complex interactions of ecological and evolutionary processes. For dioecious plants, differences in reproduction cost between sexes and sizes might affect their spatial distribution. Abiotic heterogeneity may also affect adaptation activities, and result in a unique spatial structure of the population. Thus, we examined sex- and size-related spatial distributions of old-growth forest of dioecious tree Torreya nucifera in extremely heterogeneous Gotjawal terrain of Jeju Island, South Korea. Methods: We generated a database of location, sex, and size (DBH) of T. nucifera trees for each quadrat ($160{\times}300m$) in each of the three sites previously defined (quadrat A, B, C in Site I, II, and III, respectively). T. nucifera trees were categorized into eight groups based on sex (males vs. females), size (small vs. large trees), and sex by size (small vs. large males, and small vs. large females) for spatial point pattern analysis. Univariate and bivariate spatial analyses were conducted. Results: Univariate spatial analysis showed that spatial patterns of T. nucifera trees differed among the three quadrats. In quadrat A, individual trees showed random distribution at all scales regardless of sex and size groups. When assessing univariate patterns for sex by size groups in quadrat B, small males and small females were distributed randomly at all scales whereas large males and large females were clumped. All groups in quadrat C were clustered at short distances but the pattern changed as distance was increased. Bivariate spatial analyses testing the association between sex and size groups showed that spatial segregation occurred only in quadrat C. Males and females were spatially independent at all scales. However, after controlling for size, males and females were spatially separated. Conclusions: Diverse spatial patterns of T. nucifera trees across the three sites within the Torreya Forest imply that adaptive explanations are not sufficient for understanding spatial structure in this old-growth forest. If so, the role of Gotjawal terrain in terms of creating extremely diverse microhabitats and subsequently stochastic processes of survival and mortality of trees, both of which ultimately determine spatial patterns, needs to be further examined.

Applying the L-index for Analyzing the Density of Point Features (점사상 밀도 분석을 위한 L-지표의 적용)

  • Lee, Byoung-Kil
    • Spatial Information Research
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    • v.16 no.2
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    • pp.237-247
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    • 2008
  • Statistical analysis of the coordinate information is regarded as one of the major GIS functions. Among them, one of the most fundamental analysis is density analysis of point features. For analyzing the density appropriately, determining the search radius, kernel radius, has critical importance. In this study, using L-index, known as its usefulness for choosing the kernel radius in previous researches, radius for density analysis of various point features are estimated, and the behavior of L-index is studied based on the estimated results. As results, L-index is not suitable to determine the search radius for the point features that are evenly distributed with small clusters, because the pattern of the L-index is depends on the size of the study area. But for the point features with small number of highly clustered areas, L-index is suitable, because the pattern of the L-index is not affected by the size of study area.

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Spatial Point Pattern Analysis of Riparian Tree Distribution After the 2020 Summer Extreme Flood in the Seomjin River (2020년 여름 섬진강 대홍수 이후 하천 수목 분포에 대한 공간 점 패턴 분석)

  • Lee, Keonhak;Cho, Eunsuk;Cho, Jonghun;Lee, Cheolho;Kim, Hwirae;Baek, Donghae;Kim, Won;Cho, Kang-Hyun;Kim, Daehyun
    • Ecology and Resilient Infrastructure
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    • v.9 no.2
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    • pp.83-92
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    • 2022
  • The 2020 summer extreme flood severely disturbed the riparian ecosystem of the Seomjin River. Some trees were killed by the flood impact, whereas others have recovered through epicormic regeneration after the disturbance. At the same time, several tree individuals newly germinated. This research aimed to explain the recovery of the riparian ecosystem by spatial proximity between each tree individual of different characteristics, such as "dead", "recovered", and "newly germinated". A spatial point pattern analysis based on K and g-functions revealed that the newly germinated trees and the existing trees were distributed in the spatially clumping patterns. However, further detailed analysis revealed that the new trees were statistically less attracted to the recovered trees than the dead trees, implying competitive interactions hidden in the facilitative interactions. Habitat amelioration by the existing trees positively affected the growth of the new trees, while "living" existing trees were competing with the new trees for resources. This research is expected to provide new knowledge in this era of rapid climate change, which likely induces stronger and more frequent natural disturbance than before. Environmental factors have been widely used for ecosystem modeling, but species interactions, represented by the relative spatial distribution of plant individuals, are also valuable factors explaining ecosystem dynamics.

A study on the Transformation Process of Traditional Small City Structure in Jeollabuk-Do (근대(近代) 도시화(都市化)에 따른 전라도(全羅道) 전통(傳統) 소도읍(小都邑)의 공간구조변화과정(空間構造變化過程) 연구(硏究))

  • Lee, Kyung-Chan
    • Journal of architectural history
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    • v.11 no.3 s.31
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    • pp.21-34
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    • 2002
  • This study is to analyse the transformation process of spatial structure of traditional small city structure in Jeollabuk-Do in the process of modern urbanization between 19th century and the year 2000. The small cities, IM-PI, YONG-AN, YEO-SAN, OK-GOO, GO-SAN, MU-JANG, GUM-MA, GO-BU, which have been local administrative center in CHO-SUN dynasty, have role of local administrative center of subdivision of country-myon, except OK-GOO. The method of this study is to investigate the transformation process of spatial structural elements of with the actual field surveys, the analysis of Gunhyun map made in 1872, land registration maps in 1910s and 2000, and various topological maps. The elements of analysis are the topological site and geographical situation conditions, the urbanized areas, the street systems, the function of streets, the focal points of urban land use, the land use systems, and the location of major facilities such as administration facilities, markets, bus terminals. The analytical point of view and the results are as follows. There is strong relationship between the transformation of internal matrix route system and the growth pattern of urbanized areas, Especially on the contrary to the matrix route with East-West direction which has the role of checking the growth of urbanized area, the South-North direction route acts as the leading line of the growth. The focal points structure of urban land use shows transformation process from the point of central space of administrative district in front of Nae-A, to the access point to administrative district or to the access point to housing and neighborhood commercial area. From the point of functional area structure and major facilities location, line-type commercial area is developed along the line of central axis route and access route to administrative district. Especially direction of the growth of commercial area is strongly connected with the interrelationship between the study area and its neighboring cities. Pattern of commercial district development is varied with the direction of matrix route. That is, commercial district, which shows one side development pattern along the East-West direction route, is developed on both sides of street along the South-North direction route.

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Displacement Measurement of Multi-Point Using a Pattern Recognition from Video Signal (영상 신호에서 패턴인식을 이용한 다중 포인트 변위측정)

  • Jeon, Hyeong-Seop;Choi, Young-Chul;Park, Jong-Won
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.11a
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    • pp.675-680
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    • 2008
  • This paper proposes a way to measure the displacement of a multi-point by using a pattern recognition from video signal. Generally in measuring displacement, gab sensor, which is a displacement sensor, is used. However, it is difficult to measure displacement by using a common sensor in places where it is unsuitable to attach a sensor, such as high-temperature areas or radioactive places. In this kind of places, non-contact methods should be used to measure displacement and in this study, images of CCD camera were used. When displacement is measure by using camera images, it is possible to measure displacement with a non-contact method. It is simple to install and multi-point displacement measuring device so that it is advantageous to solve problems of spatial constraints.

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An Analysis of the Visual Preference on Parallax Space by Blockage Pattern and Ratio (차폐유형과 차폐도를 달리한 패럴랙스(Parallax) 공간의 시각 선호도)

  • Rho, Jae-Hyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.35 no.2 s.121
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    • pp.55-63
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    • 2007
  • The purpose of this study is to create a planting design for progressive realization. For this, visual preferences as measured via questionnaire were evaluated by the Scenic Beauty Estimation(SBE) and paired comparison methods. The results can be summarized as follows. Through photo observation, the average visual blockage ratio was 38% and the range of degree of the visual blockage ratio was $30{\sim}50%$. The sketch simulation and filtered pattern received the highest preference score and fumed out to be the most practical pattern out of all the patterns evaluated. Also, in the sketch simulation, the high preference values were observed for a distance of 9 to 12m from the view point to the blockage tree with a D/H ratio of 2. The preference score significantly decreased with the increase of the visual blockage ratio having a turning point at $30{\sim}35%$ of the visual blockage ratio, even though the distance parameters were more important than the visual blockage ratio in the scores. An outstanding view must be handled properly to be preserved or accentuated. Framed, open, enclosed, screened or filtered pattern views should be completely revealed only from their best vantage point, not given away at first glimpse. It this sense, parallax spatial beauty with trees could be improved through the visual aspects of plan arrangements and seems to be an effective design technique for landscape planning and planting design.

Analysis of Propagation Characteristics of a Song Sung when Weeding a Rice in Chungcheongbuk-do Using the Geomorphic Elements: The Case of Short Bang-a and Sangsa ryu (지형요소를 활용한 충북 논매기소리의 전파 특성 분석: 짧은방아 및 상사류를 사례로)

  • Park, Hyun-Su;JANG, Dong-Ho
    • Journal of The Geomorphological Association of Korea
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    • v.23 no.2
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    • pp.61-70
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    • 2016
  • This study intended to analyze the spatial distribution of two types of weeding song (Short Bang-a and Sangsa ryu) and how geomorphic elements influence the propagation of the songs in Chungcheongbuk-do area. The distribution of the two types of song was mapped as point data. According to the result, both types showed similar distribution pattern. In order to figure out the reason of this similarity, the distribution pattern of songs was analyzed at various scales based on geomorphic elements including river, mountain and lineament. The result showed that most of distribution pattern of songs followed the lineament direction. Also, the spatial continuity among mountain that was formed by large and small lineament in various directions could be the path of the cultural diffusion. If the lineament with same direction does not intersect other lineament that have different direction, spatial continuity would be blocked. Consequently it was confirmed that propagation of songs has not spread smoothly.

Innovation Policies and Locational Competitiveness : Lessons from Singapore

  • Ebner, Alexander
    • Journal of Technology Innovation
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    • v.12 no.2
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    • pp.47-66
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    • 2004
  • The relationship between innovation policies and locational competitiveness has emerged as an important area in the analysis of economic development, reflecting both the centralisation and decentralisation of globalising economic activities. The underlying spatial and institutional components are subject to a pattern of cumulative causation in which strategic interventions of policy actors exercise a decisive role in shaping competitive advantages, while promoting interactions with local and foreign partners both from the private and public sectors. The Singaporean development experience illustrated these strategic interdependencies of innovation policies and locational competitiveness. Based on her role as a manufacturing and service hub, Singapore is viewed as an infrastructural nodal point which is interconnected to global production networks. Paralleling efforts in the domain of technological innovation, Singapore's policies for locational competitiveness aim at an adaptive harmonisation of the needs of international investors with local developmental objectives. This orientation characterises also current efforts in promoting Singapore as a knowledge agglomeration with a distinct science base, expanding R&D operations and an innovation-driven pattern of economic development. In conclusion, the locational rationale of Singapore's innovation policies provides lessons for dealing with the spatial and institutional implications of technological globalisation.

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An Analysis on the Change Pattern of Spatio-Temporal Land Price in Gongju City Using the Geostatistical Methods (공간통계를 이용한 공주시의 시공간적 지가변화패턴 분석)

  • Kim, Jung-Hee
    • Journal of Korean Society for Geospatial Information Science
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    • v.20 no.1
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    • pp.93-99
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    • 2012
  • This study aims to identify spatio-temporal land price change pattern in Gongju city including the area incorporated and surrounding area depending on the Multifunctional Administrative City Construction. For this, GIS data was built by calculating the average land price each 209 Dong and Ri by the time of the year 2000, 2005 and 2010 based on. The first, the change in the land price was to identify in the 5-year intervals through a kriging interpolation as a kind of geostatistical techniques. The second, a trend analysis was conducted to know directional change pattern of the east-west axis and the north-south axis. Finally, the weighted mean center was calculated by the land price at a weight to examine moving direction on the center point of land price, point of view. The result is that the land price change pattern appeared visible higher growth on the eastern built in the Multifunctional Administrative City, moving direction on the center point of the land price appeared that the phenomenon was concentrated in the northeastern area.

Spatial-Temporal Frough Analysis of South Korea Based On Neural Networks (신경망을 이용한 우리나라의 시공 간적 가뭄의 해석)

  • 신현석
    • Proceedings of the Korea Water Resources Association Conference
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    • 1998.05b
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    • pp.7-13
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    • 1998
  • A methodology to analyze and quantify regional meteorological drough based on annual precipitation data has been introduced in this paper In this study, based on posterior probability estimator and Bayesian classifier in Spatial Analysis Neural Network ISANN), point drought probabilities categorized as extreme, severe, mild, and non drought events has been defined, and a Bayesian Drought Severity Index (BPSI) has been introduced to classify the region of interest into four drought serverities. For example, the proposed methodology has been applied to analyze the regional drought of South Korea. This is a new method to classify and quantify the spatial or regional drought based on neural network pattern recognition technique and the results show that it may be apprepriate and valuable to analyze the spatial drought.

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