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1.
本文采用因子生态分析方法剖析多伦多都市区的居住空间结构。主成分分析表明,家庭构成、年龄构成、职业构成是形成城市居住分异的主要因素。聚类分析表明,家庭构成和年龄构成的分异呈同心园格局,职业构成的分异呈扇形格局。形成这种居住分异格局的机制包括动力机制、管理机制和行为机制三个方面。  相似文献   
2.
The paper reports the results of a research project aimed at the characterization of the floor bedding mortars of two Roman houses in Aquileia (north‐eastern Italy), the Domus delle Bestie Ferite and the Domus di Tito Macro. Seventy floor bedding mortars of the two domus were selected and almost half were fully minero‐petrographically characterized by means of optical microscopy operated in transmitted light (OM‐TL), X‐ray powder diffraction analyses coupled with quantitative phase analysis by means of the Rietveld method (XRPD‐QPA) and scanning electron microscopy with EDS microanalysis (SEM–EDS). The results indicate an evolution of the mortar preparation techniques over time in the mosaic of both houses. The materials are compared to the traditional Roman recipes for specific construction techniques.  相似文献   
3.
青花瓷器产地判别研究   总被引:2,自引:0,他引:2  
本项研究以江西省景德镇、云南省玉溪、建水、福建省平和的青花瓷器为主,结合香港清代碗窑以及德国、日本、泰国的现代青花瓷器,用能量色散X射线荧光(EDXRF)分析方法,在无损的情况下对其元素含量进行分析,得到了Ti、Mn、Fe、Co、Ni、Cu、Zn、Ga、Pb、Rb、Sr、Y、Zr13个元素的含量结果。用主成分分析方法对数据进行处理,利用第1主成分、第2主成分、第3主成分在三维座标系中绘制散点图,所得类群关系与已知情况完全相符。研究结果表明本文的研究方法可用于青花瓷器的产地判别。  相似文献   
4.
东部地区流动人口城市融入的比较研究   总被引:2,自引:0,他引:2  
田明  薄俊丽 《人文地理》2014,29(1):43-48
以东部地区城市特色比较明显的6个城市的问卷调查为基础,结合中国的实际情况构建了衡量流动人口城市融入的指标体系,通过主成分分析对6个城市流动人口的城市融入程度进行了比较。研究发现6个城市流动人口融入程度存在着明显的差异,环渤海的青岛和沈阳流动人口的城市融入程度最高,而珠江三角洲地区的东莞和长三角的温州流动人口的城市融入程度最低,介于两者之间的是长江三角洲地区的无锡和京津冀地区的北京。总体而言,北方城市流动人口的融入程度总体上要高于南方城市。流动人口城市融入程度的差异反映了城市特色或性质的不同。城市规模、城市所在区域的文化特色、城市经济特征、流动人口在总人口中的比例都是影响城市融入的重要因素。对于南北方流动人口城市融入的差异,方言具有很大的影响,推广普通话有利于流动人口的城市融入。  相似文献   
5.
The most common grass phytoliths from “Zambezian” miombos are described here for the first time. Their potential for long term preservation in sediments makes them a useful tool in the reconstruction of ancient plant communities and plant/human interactions. We processed 60 plant samples (26 identified genera and species), with an average of 300 phytoliths counted per sample to a total of 18,586. Forty-seven morphotypes were described as per the International Code for Phytolith Nomenclature, with exceptions, including forty-five discreet shapes and two articulated forms, which can be used as comparative reference materials. We conducted three forms of statistical analyses: Discriminant Analysis, Cluster Analysis, and Principal Component Analysis. The highest biomineral content was recorded among the Bambuseae and Paniceae, while the lowest silica production is detected in the Cynodonteae tribe. Typologically, the subfamily Panicoideae yielded 50% of the types reported here, 32% are from the Chloridoideae, 12% from the Bambusoideae, and 8% from the Arundinoideae sensu lato. Overall, the idealized Zambezian Poaceae phytolith spectrum is dominated by a small subset of Poaceae short cells, which include five morphotypes conventionally associated with Panicoid grasses (Bilobate concave outer margin long shaft, Bilobate concave outer margin short shaft, Bilobate convex outer margin long shaft, Bilobate convex outer margin short shaft, Cross), one morphotype commonly seen in Chloridoid taxa (saddle), and two types that appear across subfamily boundaries (tower, tower horned). The next logical step to take in regional phytolith research is the account of phytoliths deposited in soils underneath living plants, for they represent the interface between existing vegetation communities and the inevitably distorted fossil assemblages that the paleobotanist uses for environmental reconstruction.  相似文献   
6.
In artefact compositional studies, the selection of variables to use in analysis is unavoidable. Given this ubiquity, surprisingly little attention has been paid to ways in which variables might be selected. After arguing the case for the importance of variable selection, two systematic approaches to making a choice, which have had little or no application in archaeometry, are discussed and illustrated. One, based on the use of principal components, is appropriate if structure in the data is not known. The other, based on the use of classification trees, is applicable when there are known or assumed groups in the data.  相似文献   
7.
The 2011 great Japan Tohoku earthquake is not only the most devastating but also, one of the best recorded earthquakes in the history of seismology. A thorough study of strong motion characteristics of this earthquake is conducted using 20 well established ground motion parameters (GMPs). The behaviour of these parameters with fault distance and average shear wave velocity is examined and attenuation relationships are developed using the 1172 surface level strong motion records. In addition, all GMPs are categorized on a statistical basis using principal component analysis, which is further used to rate the damage potential of ground motion records.  相似文献   
8.
Issues related to multi-components seismic response analysis are critically reviewed and their implications with respect to the current codified approaches are studied. The issues specifically addressed are: (1) the directions of earthquake forces to excite a structure when the direction of the potential epicenter is known; (2) different commonly used combination rules to obtain the critical response when responses are available in different directions; and (3) the applicability of the combination rules for elastic and inelastic analyses. Based on an extensive parametric study consisting of three-dimensional 1-, 3-, 8-, and 15- story buildings made of moment-resisting steel frames and 20 recorded earthquakes, it is observed that the principal components produce larger responses than the normal components. The 30% and SSRS rules generally underestimate the axial loads in columns. The 30% combination rule is slightly better than the SSRS rule. For both rules, the uncertainty in the estimation of the axial loads in terms of COV is very large (about 25%). The statistics obtained for axial loads and total base shear indicate that the combination rules are applicable for both elastic and inelastic cases. The critical response could be obtained for an orientation different from that of the principal components. The differences are found to be slightly greater for the scaled earthquakes producing a considerable inelastic behavior. Considering the enormous amount of efforts needed to address the directionality effect, it is believed that the responses obtained by the principal components will be acceptable in most cases; however, for critical structures the components should be rotated to obtain the critical responses.  相似文献   
9.
Aerial photography has made the single most important contribution to our improved appreciation of the density, diversity and distribution of archaeological sites in Britain since World War Two. This is particularly the case for areas of intensive lowland agriculture where ploughed-out sites are known mainly from marks in the crops growing above them. However, reconnaissance for such cropmarks is not equally effective throughout the lowlands, because of the particular conditions of drier weather, well-drained soils and arable agriculture required before they become visible, and is highly unpredictable.  相似文献   
10.
中亚国家独立前后跨国民族的迁移对其民族结构的影响   总被引:2,自引:0,他引:2  
本文对中亚各国民族结构主体民族化的状况进行了分析研究。认为在中亚国家政局动荡、经济陷于危机的形势下,民族结构的主体民族化有利于各国暂时缓解民族矛盾和稳定政局,有利于暂时缓解失业带来的社会压力;然而从长远的发展角度来看,它侵蚀了中亚社会稳定的基石,不利于中亚各国社会的长治久安,破坏了良性的社会结构,加速了中亚社会的分化。  相似文献   
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