The Experts below are selected from a list of 72216 Experts worldwide ranked by ideXlab platform
Satoru Morita - One of the best experts on this subject based on the ideXlab platform.
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Crossovers in scale-free networks on Geographical Space
Physical Review E, 2006Co-Authors: Satoru MoritaAbstract:Complex networks are characterized by several topological properties: degree distribution, clustering coefficient, average shortest path length, etc. Using a simple model to generate scale-free networks embedded on Geographical Space, we analyze the relationship between topological properties of the network and attributes (fitness and location) of the vertices in the network. We find there are two crossovers for varying the scaling exponent of the fitness distribution.
R Hootsmans - One of the best experts on this subject based on the ideXlab platform.
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continuous classification in soil survey spatial correlation confusion and boundaries
Geoderma, 1997Co-Authors: P A Burrough, P F M Van Gaans, R HootsmansAbstract:This article traces the development of conceptual paradigms of soil classification and mapping from the pre-1960's model of crisp classes in attribute Space linked to crisply delineated mapping units in Geographical Space, to modern approaches using fuzzy classification and geostatistical interpolation for simultaneously handling continuous variation in both attributes and location. Continuous classification yields a separate map of class membership values for every class the dominance of any class at each location can be expressed by a confusion index, CI. If spatial correlation is strong, zones of high CI are concentrated in narrow Geographical transition zones between locally dominant classes: these zones can be refined to delineate automatically classspecific boundaries. If spatial correlation in membership values is weak then broad zones of large values of CI occur all over the map. Simulation modelling and two case studies demonstrate that contiguity in Geographical Space is more important for successful mapping than attribute class compactness. The studies show that soil information systems must take the spatial aspects of soil variation into account; further improvements in identifying and mapping significant soil groupings should be possible using numerical models of soil processes together with the methods presented here.
Alberto Antonioni - One of the best experts on this subject based on the ideXlab platform.
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a growing social network model in Geographical Space
Journal of Statistical Mechanics: Theory and Experiment, 2017Co-Authors: Alberto Antonioni, Marco TomassiniAbstract:In this work we propose a new model for the generation of social networks that includes their often ignored spatial aspects. The model is a growing one and links are created either taking Space into account, or disregarding Space and only considering the degree of target nodes. These two effects can be mixed linearly in arbitrary proportions through a parameter. We numerically show that for a given range of the combination parameter, and for given mean degree, the generated network class shares many important statistical features with those observed in actual social networks, including the spatial dependence of connections. Moreover, we show that the model provides a good qualitative fit to some measured social networks.
Venera Ferrito - One of the best experts on this subject based on the ideXlab platform.
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Geographical and morphological variation within and between colour phases in coris julis l 1758 a protogynous marine fish
Biological Journal of The Linnean Society, 2011Co-Authors: Carmelo Fruciano, Concetta Tigano, Venera FerritoAbstract:The possible differences between sexes in patterns of morphological variation in Geographical Space have been explored only in gonochorist freshwater species. We explored patterns of body shape variation in Geographical Space in a marine sequential hermaphrodite species, Coris julis (L. 1758), analyzing variation both within and between colour phases, through the use of geometric morphometrics and spatially-explicit statistical analyses. We also tested for the association of body shape with two environmental variables: temperature and chlorophyll a concentration, as obtained from time-series of satellite-derived data. Both colour phases showed a significant morphological variation in Geographical Space and patterns of variation divergent between phases. Although the morphological variation was qualitatively similar, individuals in the initial colour phase showed a more marked variation than individuals in the terminal phase. Body shape showed a weak but significant correlation with environmental variables, which was more pronounced in primary specimens.
Xu Zhigang - One of the best experts on this subject based on the ideXlab platform.
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Analytical Scheme on Scale-Structure of Geographical Space
Progress in geography, 2004Co-Authors: Xu ZhigangAbstract:The analytical scheme on scale-structure of Geographical Space is one of the most important fields in the study of Geographical Space. Based on scale concepts from geography and landscape ecology, and applying hierachical theory, the paper discusses the issue on macro-, middle- and basic- scales. A spatial hierachical order is primarily setup to present structures and functions of Geographical Space. The order can be used to reflect spatial structure com-ponents of epigeosphere on different scale levels and their transformation among different levels. The order will help us to find out inherent causes and their forming ways of kinds of Geographical phenomena on the basic scale, and to explore representation of different regional Geographical phenomena and their dynamic mechanism of changing process on the middle scale. Traditional geography has advantage to research macro-Space with disadvantage for micro-scale. The reasonable cognition for the hierachical order will be useful for Geographical studies on combination of macro mechanism and micro function. It will also be foundation for integration of qualitative and quantitative methods in modern geography.
