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Spatial Indexing with a Scale Dimension [chapter]

Mike HÖrhammer, Michael Freeston
1999 Lecture Notes in Computer Science  
By adding a scale dimension to the schema we make the index structure explicitly "aware" of the scale of a spatial object.  ...  In our performance measurements on databases with up to 40 million spatial objects, the introduction of a scale dimension decreased I/O by up to 4 orders of magnitude.  ...  With a scale dimension, the index structure itself is given the ability to consider only spatial objects that are sufficiently large-scale with respect to the query scale.  ... 
doi:10.1007/3-540-48482-5_6 fatcat:ggxhvzjam5fq7beahi3omnm2qm

Derivation of Correlation Dimension from Spatial Autocorrelation Functions [article]

Yanguang Chen
2021 arXiv   pre-print
However, if a spatial correlation is based on self-organized evolution, complex structure, and the distributions without characteristic scale, the eigenvalue will be ineffective.  ...  Spatial autocorrelation coefficients such as Moran's index proved to be an eigenvalue of the spatial correlation matrixes.  ...  As a matter of fact, the diagonals represent the self-correlation of spatial elements in a geographical system, e.g., city A with city A, city B with city B.  ... 
arXiv:1901.03837v4 fatcat:nqgketgqzra3hhv4z7ei3vvepq

QUANTIFYING EFFECTS OF CHANGING SPATIAL SCALE ON SPATIAL ENTROPY INDEX: USE OF FRACTAL DIMENSION

C. J. Wang, H. R. Zhao, D. M. Huang
2019 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
The result indicates that Spatial Entropy index shows a robust fractal feature, and it decreases as the spatial scale (or grain size) becomes lager in a moderate degree.  ...  A recent development is Spatial Entropy index (Hs), and it has been validated as flexible and effective in landscape pattern analysis.  ...  Slope a is then transformed into a fractal dimension measure, which indicates to what extent a certain landscape metric is sensitive to changes of the spatial scales.  ... 
doi:10.5194/isprs-archives-xlii-4-w20-83-2019 fatcat:5sqotg6kcrcnncmyrgflxvyjre

Incorporating Landscape Scaling Relations into Catchment Classification for Optimizing Ecological Management

Yingxiang Peng, Xinliang Liu, Yi Wang
2022 Sustainability  
Category I with a large relief and less anthropogenic disturbance had higher spatially non-stationary relationship, while categories II, III, and IV, with varying degrees of relatively small relief and  ...  strong intensities of anthropogenic disturbance, had a lower spatial heterogeneity of the landscape scaling relation.  ...  Compared with the scale effect and its spatial variating strength of the 12-landscape metrics, ED, DIVISION, and LSI had a strong scale effect, and these scale effects also had a large spatial variation  ... 
doi:10.3390/su14095408 fatcat:54zkczbsqjcktcn376macp56eu

Modeling Urban Growth and Form with Spatial Entropy [article]

Yanguang Chen
2020 arXiv   pre-print
Thus, for a given spatial measurement scale, fractal dimension can often be replaced by entropy for simplicity.  ...  Second, a series of indexes based on spatial entropy can be used to characterize urban form. Further, multifractal dimension spectrums can be generalized to spatial entropy spectrums.  ...  Linshan Huang of Peking University for providing spatial datasets of Beijing's land use.  ... 
arXiv:2005.02272v2 fatcat:wccjxpbxwvcabfegxyn3dhiciy

Spatial Heterogeneity of Mechanical Impedance of Atypical Chernozem: The Ecological Approach

Alexander Zhukov, Galina Gadorozhnaya
2016 Ekológia (Bratislava)  
Dimension 1 correlated with a thermal climate indicator value, a hygromorphs index, an abundance of steppe species and meadow species.  ...  Dimension 2 correlated with a continental climate indicator value, carbonate content in the soil and the soil trophicity index (capacity of the soil for plant nutrition).  ...  Along with other indicator values, the steppe plant and meadow plant canopy projection cover is the main important index to explain dimension 2.  ... 
doi:10.1515/eko-2016-0021 fatcat:jghhdb235bhvxaz2koydvwzhbi

Spatial analysis of cities using Renyi entropy and fractal parameters

Yanguang Chen, Jian Feng
2017 Chaos, Solitons & Fractals  
This study indicates that fractal dimension and spatial entropy can be combined to produce a new methodology for spatial analysis of city development.  ...  Based on this finding, a set of useful spatial indexes termed dummy multifractal parameters are defined for geographical analysis.  ...  They are just multi-scale indexes of spatial structure bearing an analogy with multifractal parameters in fractal geometry.  ... 
doi:10.1016/j.chaos.2017.10.018 fatcat:sr3pckwlwrczdl2tvcghedar4u

Scaling Effect on the Relationship between Landscape Pattern and Land Surface Temperature

Hua Liu, Qihao Weng
2009 Photogrammetric Engineering and Remote Sensing  
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING M a r c h 2 0 0 9 291 Hua Liu is with the  ...  Each LULC and LST image was resampled to eight spatial scales: 15, 30, 60, 90, 120, 250, 500, and 1,000 m.  ...  Acknowledgments This research was supported by National Science Foundation (BCS-0521734) for a project entitled "Role of Urban Canopy Composition and Structure in Determining Heat Islands: A Synthesis  ... 
doi:10.14358/pers.75.3.291 fatcat:3qfrh736g5ezfjds6z7n7v3nxu

Gossip-Based Indexing Ring Topology for 2-Dimension Spatial Data in Overlay Networks

Z.Q. Zou, Y. Wang, B. Hu, R.C. Wang
2012 Procedia Engineering  
This article presents a new indexing overlay networks, named 2D-Ring, which is the ring topology based on gossip for 2-dimension spatial data.  ...  In such way, the problem of 2-dimension spatial data indexing is converted to the problem of searching peers in the 2D-Ring.  ...  First, we introduce a new algorithm based on gossip, which can construct a spatial data indexing overlay networks, named 2D-Ring. Second, we design a large-scale spatial information indexing method.  ... 
doi:10.1016/j.proeng.2012.01.561 fatcat:pgq5gzpek5f6zcv2kjwttadmhq

Exploring Residential Heterogeneity through Multiscalar Lens: A Case Study of Hangzhou, China

Qinshi Huang, Weixuan Song, Liyan Liu, Chunhui Liu, Xinyi Zhang, Ge He, Jun Yang
2021 Complexity  
The pattern, process, and mechanism of residential heterogeneity vary significantly with different geographical scales.  ...  Taking Hangzhou city as an example, a multiscalar method was proposed based on the information entropy theory to estimate residential heterogeneity and its scale sensitivity.  ...  Here, we use the information entropy index (H) and spatial information entropy index (H), combining with exposure isolation index (xPx) and spatial exposure isolation index (xPx), to assess the residential  ... 
doi:10.1155/2021/3798183 fatcat:e5tchey6drbfxhwxww4htxx5lu

The Spatial Distribution Characteristics of the Cultivated Land Quality in the Diluvial Fan Terrain of the Arid Region: A Case Study of Jimsar County, Xinjiang, China

Yang Sheng, Weizhong Liu, Hailiang Xu, Xianchao Gao
2021 Land  
comprehensive evaluation method and constructs a comprehensive evaluation index system for cultivated land quality on account of three dimensions, namely soil properties, farming conditions, and natural  ...  Based on the case study of diluvial fan terrain in Jimsar County, Xinjiang in the arid region of Northwest China, this study utilizes a geographic information system spatial analysis and a multifactor  ...  interpolation methods of three dimensions with large-scale cultivated land.  ... 
doi:10.3390/land10090896 fatcat:wqvaulgkmbaxpdcjs4gngnprom

Similarity search in content-based multimedia retrieval using spatial grid files

Adil Alpkocak, Esen Ozkarahan, C.-C. Jay Kuo, Shih-Fu Chang, Sethuraman Panchanathan
1998 Multimedia Storage and Archiving Systems III  
In this paper, we introduce a new file structure called Spatial Grid File (SGF). This file structure enables to index multimedia objects by different and independent high-dimensional feature vectors.  ...  Therefore, a multimedia information system must employ multiple search and indexing mechanisms due to integration of multiple search modalities such as querying for search and for indexing, keywords and  ...  Each axis (dimension) of SGF is called linear scale, which is organized as an object class with its data and method parts.  ... 
doi:10.1117/12.325809 fatcat:w337o44uarefxdxehieo23ov5e

Global and local spatial indices of urban segregation

F. F. Feitosa, G. Câmara, A. M. V. Monteiro, T. Koschitzki, M. P. S. Silva
2007 International Journal of Geographical Information Science  
This paper proposes global spatial indices of segregation that capture interaction among population groups at different scales.  ...  The proposed indices are illustrated using an artificial dataset and a case study of socio-economic segregation in São José dos Campos (SP, Brazil).  ...  Spatial isolation index of family heads with income greater than 20 MW. 15 > Q ( Spatial isolation index of family heads with 15 years of schooling or more. 0 Q ( Spatial isolation index of family heads  ... 
doi:10.1080/13658810600911903 fatcat:bjnwd7drizf23jvl3bwhp2wqri

Examining the Satellite-Detected Urban Land Use Spatial Patterns Using Multidimensional Fractal Dimension Indices

Hao Wu, Yurong Sun, Wenzhong Shi, Xiaoling Chen, Dongjie Fu
2013 Remote Sensing  
than any single fractal dimension index.  ...  Due to the nonlinear features associated with land use spatial patterns, it is currently necessary to provide some distinct analysis methods to analyze them across a range of remote sensing imagery resolutions  ...  lacunarity dimension to solve the typical modifiable areal unit problem associated with the scale effects of lacunarity index.  ... 
doi:10.3390/rs5105152 fatcat:delblpaq6nejxeyjqmgeftjcfq

The vegetation cycle in West Africa from AVHRR–NDVI data: Horizons of predictability versus spatial scales

S. Mangiarotti, P. Mazzega, P. Hiernaux, E. Mougin
2010 Remote Sensing of Environment  
The predictability of the vegetation cycle is analyzed as a function of the spatial scale over West Africa during the period 1982-2004.  ...  The times series are then embedded in a low-dimensional pseudo-phase space using a system of time delayed coordinates.  ...  Based on a French initiative, AMMA was built by an international scientific group and is currently funded by a large number of agencies, especially from France, the UK, the USA and Africa.  ... 
doi:10.1016/j.rse.2010.04.010 fatcat:lv6ygiztjneapjereohycp5aw4
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