• Title/Summary/Keyword: spatial distribution pattern

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Selection of Spatial Regression Model Using Point Pattern Analysis

  • Shin, Hyun Su;Lee, Sang-Kyeong;Lee, Byoungkil
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.3
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    • pp.225-231
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    • 2014
  • When a spatial regression model that uses kernel density values as a dependent variable is applied to retail business data, a unique model cannot be selected because kernel density values change following kernel bandwidths. To overcome this problem, this paper suggests how to use the point pattern analysis, especially the L-index to select a unique spatial regression model. In this study, kernel density values of retail business are computed by the bandwidth, the distance of the maximum L-index and used as the dependent variable of spatial regression model. To test this procedure, we apply it to meeting room business data in Seoul, Korea. As a result, a spatial error model (SEM) is selected between two popular spatial regression models, a spatial lag model and a spatial error model. Also, a unique SEM based on the real distribution of retail business is selected. We confirm that there is a trade-off between the goodness of fit of the SEM and the real distribution of meeting room business over the bandwidth of maximum L-index.

Spatial Distribution Pattern of Ascotis selenaria (Lepidoptera: Geometridae) larvae in a Small-Scale of Citrus Orchard (소규모 감귤원에서 네눈쑥가지나방 유충의 공간분포 특성에 대한 이해)

  • Choi, Kyung San;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.52 no.3
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    • pp.243-248
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    • 2013
  • This study was conducted to understand the settlement process of Ascotis selenaria larvae into citrus orchards with respect to oviposition site and analysis of the spatial distribution pattern of the larvae. A. selenaria eggs were not found on citrus trees in field and green house, but not on citrus trees in the field. A. selenaria larvae showed a significant clump distribution in the greenhouse. In the open citrus field, the index of dispersion was around 1.0 in most cases, with a weak clumping degree. However, the d-statistic was between -1.96 and 1.96, indicating a statistically significant random distribution. In addition, the Green's index (a clumping index) was very low in all cases, even though the clump distribution was accepted. for most samples, the probability distribution of larval frequency in the field satisfied the probability distribution functions of Poisson (random pattern) and the negative binomial (clump pattern) distribution. In addition, the temporal distribution of the larvae in the open field showed a pattern which was formed by colonizers from outside oviposition sites. Further, the difference in larval spatial distribution between field and greenhouse orchards was discussed.

Analysis of Urban Distribution Pattern with Satellite Imagery

  • Roh, Young-Hee;Jeong, Jae-Joon
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.616-619
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    • 2007
  • Nowadays, urbanized area expands its boundary, and distribution of urbanized area is gradually transformed into more complicated pattern. In Korea, SMA(Seoul Metropolitan Area) has outstanding urbanized area since 1950s. But it is ambiguous whether urban distribution is clustered or dispersed. This study aims to show the way in which expansion of urbanized area impacts on spatial distribution pattern of urbanized area. We use quadrat analysis, nearest-neighbor analysis and fractal analysis to know distribution pattern of urbanized area in time-series urban growth. The quadrat analysis indicates that distribution pattern of urbanized area is clustered but the cohesion is gradually weakened. And the nearest-neighbor analysis shows that point patterns are changed that urbanized area distribution pattern is progressively changed from clustered pattern into dispersed pattern. The fractal dimension analysis shows that 1972's distribution dimension is 1.428 and 2000's dimension is 1.777. Therefore, as time goes by, the complexity of urbanized area is more increased through the years. As a result, we can show that the cohesion of the urbanized area is weakened and complicated.

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A Spatial Analysis on the Formation and Dissolution of Start-up Firms in the Seoul Metropolitan Region (수도권 창업기업의 생멸에 대한 공간분포 패턴 분석)

  • Yi, Chang-Hyo
    • Journal of Cadastre & Land InformatiX
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    • v.45 no.1
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    • pp.241-256
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    • 2015
  • The purpose of this paper is to verify the spatial distribution difference between formation and dissolution of start-up firms related to life-cycle. For this purpose, a Korean business directories and information on business closures were used, and location information, starting time, and closure time of start-up firms in the Seoul metropolitan region from 2007 to 2009 were generated in this study. It applied The spatial distribution analysis methods on the formation and dissolution of the start-up firms included Barcki measurements and global spatial autocorrelation. The total number of start-up firms was 5,810, and their five-year survival rate was 77.25%. The dissolution pattern of the start-up firms was dispersed more than their formation pattern in each of the Seoul metropolitan regions, the city of Seoul, and the city of Incheon-Gyeonggi province. In addition, differences between the formation and dissolution patterns according to size and industry category of the firms were confirmed.

Missing Pattern Analysis of the GOCI-I Optical Satellite Image Data

  • Jeon, Ho-Kun;Cho, Hong Yeon
    • Ocean and Polar Research
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    • v.44 no.2
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    • pp.179-190
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    • 2022
  • Data missing in optical satellite images caused by natural variations have been a crucial barrier in observing the status of marine surfaces. Although there have been many attempts to fill the gaps of non-observation, there is little research to analyze the ratio of missing grids to overall sea grids and their seasonal patterns. This report introduces the method of quantifying the distribution of missing points and then shows how the missing points have spatial correlation and seasonal trends. Both temporal and spatial integration methods are compared to assess the effectiveness of reducing missing data. The temporal integration shows more outstanding performance than the spatial integration. Moran's I and K-function with statistical hypothesis testing show that missing grids are clustered and there is a non-random distribution from daily integration. The result of the seasonality test for Moran's I through a periodogram shows dependency on full-year, half-year, and quarter-year periods respectively. These analysis results can be used to deduce appropriate integration periods with permissible estimation errors.

Analysis for Dispersal and Spatial Pattern of Metcalfa pruinosa (Hemiptera: Flatidae) in Southern Sweet Persimmon Orchard (남부지방 단감원에서 미국선녀벌레의 분산 및 공간분포 분석)

  • Park, Bueyong;Kim, Min-Jung;Lee, Sang-Ku;Kim, Gil-Hah
    • Korean journal of applied entomology
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    • v.58 no.4
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    • pp.291-297
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    • 2019
  • Since Metcalfa pruinosa was first reported in Koera, it has continually caused damage to sweet persimmon orchard in southern part of Korea. Metcafa pruinosa exist not only in farmland but also in forest areas, and are difficult to control due to the influx of individuals from near forest. M. pruinosa has been occurred in orchard and its surroundings because of various host range. Thus, it has been difficult to decide spatial range and control time for efficient management. In this study, occurrence and dispersal pattern of M. pruinosa in persimmon orchard were surveyed using clear sticky traps, and spatial patterns were analyzed with SADIE(Spatial Analysis by Distance IndicEs), based on location information at sticky traps. Spatial association between survey time was also analyzed to identify when the spatial pattern changed. In sweet persimmon orchard, M. pruinosa mainly dispersed in mid to late May, when the first instar hatches, and in August, emerging season of adult. The first instar nymphs hatched in mid-May were randomly distributed in orchard, but distribution was changed to aggregative pattern after dispersed surroundings of orchard. Adults showed random distribution pattern after immigration to orchard again. These tendency was also observed in density change at orchard and its surroundings, and matched to actual density of M. pruinosa in sweet persimmon trees.

Prediction of Rock Fragmentation and Design of Blasting Pattern based on 3-D Spatial Distribution of Rock Factor (발파암 계수의 3차원 공간 분포에 기초한 암석 파쇄도 예측 및 발파 패턴 설계)

  • Shim Hyun-Jin;Seo Jong-Seok;Ryu Dong-Woo
    • Tunnel and Underground Space
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    • v.15 no.4 s.57
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    • pp.264-274
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    • 2005
  • The optimum blasting pattern to excavate a quarry efficiently and economically can be determined based on the minimum production cost which is generally estimated according to rock fragmentation. Therefore it is a critical problem to predict fragment size distribution of blasted rocks over an entire quarry. By comparing various prediction models, it can be ascertained that the result obtained from Kuz-Ram model relatively coincides with that of field measurements. Kuz-Ram model uses the concept of rock factor to signify conditions of rock mass such as block size, rock jointing, strength and others. For the evaluation of total production cost, it is imperative to estimate 3-D spatial distribution of rock factor for the entire quarry. In this study, a sequential indicator simulation technique is adopted for estimation of spatial distribution of rock factor due to its higher reproducibility of spatial variability and distribution models than Kriging methods. Further, this can reduce the uncertainty of predictor using distribution information of sample data The entire quarry is classified into three types of rock mass and optimum blasting pattern is proposed for each type based on 3-D spatial distribution of rock factor. In addition, plane maps of rock factor distribution for each ground levels is provided to estimate production costs for each process and to make a plan for an optimum blasting pattern.

A Study on the Realization of Variable Spatial Filtering Detector with Multi-Value Weighting Function (계측용 공간필터의 가변적 다치화된 가중치 실현에 관한 연구)

  • Jeong, Jun-Ik;Han, Young-Bae;Go, Hyun-Min;Rho, Do-Hwan
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.481-483
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    • 1998
  • In general, spatial filtering method was proposed to simplify measurement system through parallel Processing hardware. Spatial filtering is a method of detection that we can get a spatial pattern information, as we process a special space pattern, to say, as we process spatial parallel process by using the spatial weighting function. The important processing characteristics will be depended in according to how ire design a spatial weighting function, a spatial sensitive distribution. The form of the weighting function which is realized from the generally used spatial filtering is fixed and the weighting value was already became a binary-value. In this paper, we propose a new method in order to construct adaptive measurement systems. This method is a weighting function design to make multi-valued and variable.

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Spatial Distribution Pattern of Users by the Types of Use Activity at Lawn Areas in Park (공원잔디공간의 이용활동유형별 공간분포특성에 관한 연구)

  • 암봉훈
    • Asian Journal of Turfgrass Science
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    • v.10 no.1
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    • pp.13-20
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    • 1996
  • This study was carried out to investigate the characteristics of spatial distributon patterns of users by each type of recreational activities at lawn areas in the parks. Study sites were lawn areas at Kyungju World and Seorabul Plaza in Bomun Resort Complex in Kyungju, Korea. Space types by each recreation activities are Repose Type, Sports Type, Play Type and Strolling Type. Main results are as follows ; 1. Sport Type activities were mainly distributed at the central areas of each lawn areas. 2.The density of Sports Type activities were affected by the form of lawn areas. For natural control of excess dynamic activities, Complex Form has more advantage in the distribution of dynamic activities. So, as the form of lawn areas in the parks, complex form is more desirable. 3.Repose Typo activities were distributed at marginal areas of lawns and surrounding woods. These, the static activities, were affected by Edge Effect in spatial distribution of activities. 4.Play Typo activities also were distributed at marginal areas of lawns. It was also affected by Edge Effect in spatial distribution. 5.Strolling Type activities were distributed evenly over all lawn areas.

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The Campus of University Earthquake Disaster Prevention Planning - The Research of Spatial Pattern Based on GIS

  • Mi, Shan;Piao, Yong-Ji;Zhang, Rui;Cho, Tae-Dong
    • Journal of Environmental Science International
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    • v.23 no.7
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    • pp.1213-1221
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    • 2014
  • In the background of rapid urbanization and frequent earthquakes, earthquake disaster prevention planning has become an important topic of current research. Universities are irreplaceable disaster shelter, as they are public institutions with a lot of open space. This article puts forward the concept of "disaster prevention campus". With the refuge behavioral and psychological characteristics of people in the campus when the earthquake happens, it integrated uses GIS spatial analysis technique, takes Shandong Agricultural University as an example, and studies the spatial pattern of earthquake disaster prevention planning in campus from five aspects. The aspects include building distribution, population distribution, analysis of service radius, infrastructure configuration and choice of the optimal refuge path. On the basis of researches above, reform proposals and specific strategies are put forward to build the safe and harmonious disaster prevention campus.