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Mehmet Ali Yüzer 《European Planning Studies》2004,12(4):551-561
This article describes the main features of a Land Use Cellular Automata Model (LUCAM) developed within the scope a Ph.D. thesis by using both physical and socio‐economic data and on the basis of the relationships between the smallest cellular function and other functions that vary according to the fractal structure of settlements. An assessment of the research findings is also included. The article has five sections: Following the introduction, the evolution of land use models, in particular Cellular Automata (CA) based land use models, is described. Then, the main features of LUCAM are presented, and the basics of the criteria used in determining the model parameters is described. The model developed, which can easily be used in computer environments, aims to minimize the calculation time in growth estimation processes, and thus become a widely used tool. In this article, the model was applied to the settlement of Bursa (Turkey), and the results obtained were assessed. The conclusion section offers general guidelines on the use of the model and discusses the advantages of employing the model in CA based studies that are likely to emerge in the future. 相似文献
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抗战初期的南调命令是国民党在发展和维护它的华中敌后利益,尤其是大别山根据地利益的过程中提出来的.由于抗战的新形势,国民党对在失去大举"剿共"手段之后的策略选择和反共部署,其实并没有多少及时而深入的考虑,尤其因为共产国际五月指示以来共产党在华中采取攻势策略,国民党更显缺乏心理和策略准备,南调命令最终在国民党内外重重阻力下不了了之.但是,这并不意味着它在国共关系史上没有产生实际的影响.在皖南,国共都因为南调命令而发生了策略变化,两党由此不可避免地开始积累矛盾,直至事变发生. 相似文献
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Wild or domesticated: DNA analysis of ancient water buffalo remains from north China 总被引:1,自引:0,他引:1
Dongya Y. Yang Li Liu Xingcan Chen Camilla F. Speller 《Journal of archaeological science》2008,35(10):2778-2785
Recent zooarchaeological studies on water buffalo (Bubalus sp.) remains from China and south Asia question the traditional view that water buffalo were first domesticated in Neolithic China over 7000 years ago. The results from several recent population genetic studies of modern domesticated buffalo (Bubalus bubalis) are not consistent with each other, placing the original center of buffalo's domestication in south Asia, southeast Asia, or China. This paper reports a study using an ancient DNA approach to analyze water buffalo remains from Neolithic sites in north China to investigate their affinities with modern domesticated water buffalo, and to shed light on the origin of modern domesticated water buffalo in China.A 169 bp fragment of D-loop mitochondrial DNA was successfully amplified and verified for 13 of 24 bone samples obtained from seven archaeological sites along the Wei River valley in Shaanxi Province, China. The bone samples which yielded positive DNA can be dated to 8000–3600 cal. BP. The phylogenetic analysis of the obtained DNA sequences along with modern water buffalo sequences indicated that the ancient water buffalos were not the direct ancestor of modern domesticated water buffalo. However, the phylogenetic analysis, along with BLAST searches of these ancient DNA sequences, did demonstrate their relatedness to water buffalo more so than to any other bovid species, confirming the existence of indigenous wild (but now extinct) water buffalo species (B. mephistopheles) in ancient China.The DNA analysis of these ancient remains failed to establish direct links between modern domesticated water buffalo (B. bubalis) and indigenous water buffalo (B. mephistopheles) from ancient China. If further DNA studies of more ancient remains from other regions of China confirm the observation of solely indigenous water buffalo species in ancient China, it would suggest modern water buffalo might not have been first domesticated in China. 相似文献
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Y. FernndezJalvo B. SnchezChilln P. Andrews S. FernndezLpez L. Alcal Martínez 《Archaeometry》2002,44(3):353-361
The aim of this paper is to provide a summary of structural or surface modifications of vertebrate bone remains in continental palaeoenvironments that may have repercussions on their chemical composition. Both before and after burial, a different set of physical, chemical and biological agencies may produce modifications of the bone morphological structure and/or bone chemical composition. Several of these morphological modifications are diagnostic of particular agents, which otherwise may not be noticed or identified in a fossil association. In order to understand diagenesis, those events that occurred before final burial have to be considered, as they may strongly modify the bone morphological structure and influence post–burial changes. 相似文献
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RECENT CHANGES IN THE PATTERN OF FARMING IN ICELAND 总被引:1,自引:0,他引:1
I. Y. ASHWELL 《The Canadian geographer》1963,7(4):174-181