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1.
本文对青海古代各历史时期的文化遗址及文物进行了分析与探讨,提出了青海古代文化遗址有着分布的集中性、石器时代的完整性以及多元结构的民族文化特点;论证了以上特点是由地理环境及历史的各民族文化活动所致。 相似文献
2.
迄今已有2 700多年历史的铜鼓,是南方少数民族地区节日、喜庆、兵事、婚丧、祭祀、礼乐等场合使用的一种重器。为了对锈蚀状况做出科学的现状评估,为器物保护修复技术路线的制定和修复工作的开展提供科学指导,对玉林市博物馆馆藏7件铜鼓综合运用了体视显微镜、金相显微镜、激光显微拉曼光谱仪(RS)和环境扫描电镜及能谱仪(ESEM-EDAX)等仪器进行了金相组织和合金成分分析以及锈蚀产物的分析。分析结果显示:7件器物皆为泥范铸造成型,未见热、冷加工处理现象。7件铜鼓皆为铅锡青铜合金,总体呈低锡高铅的特点。组织形态呈典型α固溶体树枝晶偏析,锡含量处于6.0%~12.2%,分布较为集中,处于中等含量水平(5%≤Sn15%);铅含量处于14.4%~28.2%,铅含量普遍较高且分布较为集中,处于中高铅(10%≤Pb15%)和高铅含量(Pb≥15%)水平,合金中高铅含量配比应为工匠有意合金配比选择;铜鼓的腐蚀类型为α固溶体富铜相优先腐蚀,保存环境主要是富氧、少氯,铜鼓表面锈蚀产物主要为绿色孔雀石和蓝色蓝铜矿以及氧化物,有少量白色白铅矿。在保护修复工作中对于这些无害锈可保留,不予处理,并注重防氧。对于铜鼓表面夹杂泥土,需进行清洗去除。研究结果可为器物保护修复技术路线的制定和修复工作的开展提供科学指导。 相似文献
3.
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
4.
Dario Musolino 《Journal of Cultural Geography》2018,35(2):251-273
ABSTRACTGeographers interested in how entrepreneurs perceive locational environments have studied their mental maps in several European countries, within the theoretical framework provided by behavioral approach. Such studies have typically employed quantitative techniques, but qualitative studies are relatively new to this line of research. In this article, I examine the mental maps of entrepreneurs in Italy by using a mixture of qualitative and quantitative methods. I present and discuss the qualitative outcomes of this research, focusing in particular on the explanatory location factors and the key influences on the mental maps of entrepreneurs. What emerges is the realization that entrepreneurs are far from being fully rational economic actors, who exploit optimally all information and who are driven only by objective considerations. Rather, their views are also affected by subjective factors, individual’s own insights, commonplaces, stereotypes, and prejudices, particularly with reference to the southern regions of Italy (Mezzogiorno), and of other peripheral areas. 相似文献
5.
Based on a study in four Norwegian cities (Oslo, Stavanger/Sandnes, Bergen and Trondheim) differing in size and centre structure, this article illuminates how residential and workplace location, local-area density and transit accessibility influence different aspects of travel behaviour. We find strong effects of residential and workplace distance to the city centre on overall driving distances and commuting distances. We also find clear effects of local area densities around residences and workplaces on the choice of car as a travel mode, along with less pronounced effects of the distance from dwellings and workplaces to the city centre. In the cities with the best developed transit provision, we also see clear effects of transit accessibility at the residence on the propensity of choosing the car as travel mode. The results provide strong support of Norwegian national policies of urban densification as a planning strategy to curb the growth in urban motoring. However, although the influences of urban structure on travel show many similarities across the four cities, there are also important differences reflecting variations in centre structure (predominantly mono- or polycentric) and population size. The magnitude of the influences of various urban structural characteristics on travel behaviour are thus highly context-dependent. 相似文献
6.
7.
Richard Dyson 《Family & Community History》2018,21(1):3-14
This article examines the wealthier inhabitants of Croydon in the late sixteenth and early seventeenth centuries, focusing on differences in wealth, ownership of property and social relationships. Using wills and subsidy lists, four broad categories of people were identified: gentlemen, yeomen, tradesmen and craftsmen and widows. There was no simple gradation of wealth between these groups; although gentlemen were generally among the richest subsidy payers, yeomen and tradesmen could also figure. In terms of social relationships and the ownership of property, there were differences. Gentlemen tended to marry within their own social group, appoint other gentlemen as overseers in their wills and were more likely to own land outside Croydon. The social relationships of yeomen and tradesmen/craftsmen were more focused on the town itself, as were their land purchases. Two groups of individuals can therefore be seen, not one homogenous entity as some scholars have argued. 相似文献
8.
Henk M. van der Velde Johanna A. A. Bos Gert L. Kortekaas Frieda S. Zuidhoff 《Environmental Archaeology》2018,23(4):389-402
ABSTRACTThis paper will examine settlement location during the Iron Age in the northeast part of the Netherlands, an area shaped by Pleistocene geology. In recent years, a number of Late Iron Age/Early Roman settlements situated on the low lying slopes of sand ridges and nearby stream ridges revealed traces of an earlier Iron Age occupation. Palynological data revealed that this part of the landscape was used by humans before it was transformed into an area of settlement. An analysis of excavation data from two key sites at Denekamp-De Borchert and Groningen-Helpermaar, as well as other known sites, lead to the conclusion that the transformation of ‘peripheral landscapes’ into permanent settlement locations was preceded by a phase of arable cultivation which left no trace of permanent habitation. It is also suggested that the impact of human behaviour on the natural landscape in the Early and Middle Iron Age was much bigger than previously anticipated. When excavating this type of settlement areas dating to the Late Iron Age, archaeologists must be aware that only of a small group of archaeological features exist. The proposed model for the choice of settlement location may be more widespread, because of similarities in landscape between the study area presented here and other landscapes in Northwest-Europe (e.g. parts of Germany and Denmark). 相似文献
9.
Carla Ceraldi Maria Lippiello Claudio D’ambra Andrea Prota 《International Journal of Architectural Heritage》2018,12(3):362-375
ABSTRACTThe employment of timber pegs in timber structure joints is a widespread technology in the field of timber frame building in the United States, where the Timber Frame Engineering Council has published a special Standard to supplement the National Design Specification for Wood Construction. The authors have been studying the possibility of supplementing the Eurocode 5 design formulas, thought for timber joints with metal connectors, with specifications needed for a reliable design when employing timber pegs. The field of application envisaged is that of restoring timber structures and results obtained until now are quite encouraging. In this step of the research, more attention has been paid to deformation process: fir and chestnut samples have been tested to determine their dowel-bearing behavior with steel and ash timber peg while double-shear plane joints made of the same wood species, and fastened with steel as well as timber pegs, have been analyzed. 相似文献
10.
In the context of changing demand for fire services, spatial optimisation of fire coverage has attracted little scholarly attention despite its potential to improve emergency response and to inform future service planning for fire stations. Drawing on small area population forecasts, this paper extends the application of the Maximum Coverage Location Model to compute and delineate the spatial coverage of current and proposed new fire stations to align with population growth estimates for Brisbane, Australia. Our results reveal important gaps in fire cover that are likely to emerge as a result of predicted population growth, the spatial patterns of which varies across the Brisbane metropolitan area. We draw on these results to delineate a series of new potential sites for fire stations to ameliorate the reduction in spatial coverage as a consequence of predicted population growth demonstrating the utility of our analytic approach for decision‐making and operational planning in the fire services. 相似文献