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41.
This work was aimed at developing a practical and simple settlement estimation of shallow foundation on liquefiable deposits. The study conducted a centrifuge test, a series of comprehensive numerical analysis, back analysis, equation calibration, and verification with data from not only centrifuge test but also the literature. It finally proposed a quick calculation method based on Meyerhof’s settlement equation (1965). A two-dimensional numerical analysis, named ALID, (Analysis for Liquefaction-induced Deformation), was employed for obtaining settlement of shallow foundations on liquefiable soils with different relative densities under various seismic conditions. Its performance was first verified through a centrifuge test conducted in this study. Then, the developed method based on Meyerhof’s settlement equation was employed, and a new parameter, NLR, was proposed to present the strength of liquefied soils by replacing N value in the original equation. The NLR was obtained through back analysis of the numerical results and modified accordingly after comparison with the data from the literature. This paper, finally, demonstrated the practical use of the proposed method involving NLR by predicting 199 sets of liquefaction-induced settlement of shallow foundation reported in the past, including a latest most liquefaction-induced settlement of a house in 0206 earthquake on February 6, 2016, in Taiwan.  相似文献   
42.
Abstract

Before timber and stone houses were introduced to northern regions, varieties of turf houses were the most commonly used architecture. These houses had a wooden structure encapsulated in a shell constructed of grass turf. The different ethnic groups of the north built their houses in different styles and constructions, but the general principle was the same. The Norse of North Norway and also on the North Atlantic islands had a tendency to build their houses on top of the ruins of previous houses. After a few centuries this arrangement produced a settlement mound of highly organic soil. In the research literature, both the turf architecture and the settlement mounds have been described as adaptations to and a function of marginality and lack of timber. This paper reports an effort to test the idea that turf houses on top of settlement mounds may have been a finely tuned ecological system that made use of the capacity of organic soil to produce heat.  相似文献   
43.
Abstract

The Early Metal Period (1800 cal BC–AD 300) of the Finnish inland regions is characterized by a scarcity of archaeological remains. Its latest stages, in particular, have proved to be difficult to interpret. This paper discusses the continuity of settlement in the Early Metal Period as indicated by archaeological survey and pollen-analytical data. The study area is situated in Repovesi National Park in southeastern Finland. The pollen analysis was constructed from a sediment sequence taken from Lake Katajajärvi. The archaeological survey data from Repovesi National Park supports earlier hypotheses of the small number of Early Metal Period sites. In the pollen data, the first anthropogenic impact is recorded from about 2600 BC onwards, with weak signs of cultivation around 2370 BC. From around 1900 BC onwards a clear change in tree, shrub and herb pollen percentages indicates anthropogenic impact, possibly grazing, in the area. The pollen-analytical results also revealed a cultivation period of about 900 years at the end of the Early Metal Period, providing proof of continuity in settlement during a period characterized by a scarcity of archaeological material. A new beginning of cultivation from cal AD 1160 to 1250 onwards can be considered as indicating population growth, developing settlements and the colonization of new areas. The results from Repovesi are challenging from an archaeological point of view, because they represent slash-and-burn cultivation that appears to have been practised in total wilderness conditions. Comparison of the Lake Katajajärvi results with other areas raises new questions that call for a discussion of early slash-and-burn cultivation in new perspective.  相似文献   
44.
This article proposes that anthropologists and historians of colonialism, landscape and the colonial construction of chieftaincy in Africa should examine particular case studies in more detail to elicit the complex social and material processes implicit in such notions. In particular it focuses upon the colonial conflation of the notions of settlement nucleation and sedentism in the period of the Bechuanaland Protectorate in Botswana (1885–1966), processes of material change, and the position of Tswana chiefs with regard to settlement and authority. The perceived “failure” of the Tawana chiefs in Ngamiland District to exert settlement control over the dispersed population is analyzed through detailed colonial records of conflict to argue that what failed was the colonial construction of chieftaincy itself, as well as the colonial imagination of landscape in Africa. The article’s emphasis upon the materiality of dwelling in the landscape also seeks to convince historians and anthropologists alike of the vast research potential of material culture in the analysis of colonial histories, social and cultural change, and indigenous notions of modernity.  相似文献   
45.
The archaeological reconstruction of ancient states requires consistent regional measures of state-directed power and influence. This paper presents data from a series of systematic archaeological surveys in the Cusco region of highland Peru to evaluate patterns of influence by the Wari state during a period of colonization from ca. AD 600–1000. We discuss interpretive debates over the nature and intensity of Wari social power, suggesting that site-based studies can be contextualized meaningfully using our large-scale dataset, which offers settlement patterns at varying distances (0–70 km) from Pikillacta, a Wari administrative center. We discuss local settlement patterns before and during Wari colonization, as well as the distribution of Wari pottery and local Wari-influenced wares. We then use a geographic information systems analysis of travel time from key sites to evaluate the broad regional distribution patterns of local and Wari ceramic styles. Although the regional survey data do not inform us reliably about all kinds of social power, we conclude that the Wari cultural, economic, and political influence over the Cusco region was limited and discontinuous—an example of colonization that resembles the practices of other early states.  相似文献   
46.
Radial systems of spoke-like pathways, often termed “hollow ways,” are frequently found surrounding mounded tell sites in northern Mesopotamia and have been explained as the product of a particular set of land use practices involving dry-farming agriculture and intensive ovicaprid pastoralism. Yet while similar subsistence strategies were very common across the Near East throughout much of the Holocene, classic hollow ways have only been previously documented in a small region and articulate almost exclusively with sites of the third millennium BC. This paper presents newly discovered hollow ways in western Syria and southwestern Iran, made possible through analysis of an online database of declassified, Cold War-era CORONA satellite imagery. The association of these previously undocumented ancient roads with archaeological sites dating to the Iron Age, Roman/late Roman and early medieval periods, suggests that the land use practices which produced radial route systems may have been quite widespread. Taking into account the wide geographic and temporal distribution of hollow ways, analysis explores various aspects of the agro-pastoral systems that disparate communities may have shared. Results confirm some aspects existing models of hollow way formation, while offering some refinements in terms of the roles that settlement organization, agricultural land use and pastoral strategies play.  相似文献   
47.
中原龙山城址的聚落考古学研究   总被引:9,自引:4,他引:5  
在夏商周文明发祥的中原地区,诸多龙山城址已具早期城市性质,并形成了以城址为中心、明显具有不稳定性和对抗性特点的扇形聚落群布局结构.其中聚落群同盟组织的存在可能是扇形聚落群成立的社会基础,而导致扇形聚落群及其同盟组织发生的原因则应是中原地区居民所面临的巨大生存压力.  相似文献   
48.
张一平 《史学月刊》2000,(1):111-115
20世纪的世界已是一个整体,各国各民族都是世界整体的各个局部,各个重大事件都是世界历史链条上的各个环节。不应孤立地考察某个历史事件或某一国家的命运,而应从世界整体历史的角度,去把握历史事件的内在联系。李植栴主编的《20世纪世界史》的突出特点,就在于整体研究。但该有所忽视的是,世界历史整体与外部环境的关系。  相似文献   
49.
易溶盐富集是陕西西安大雁塔砖体表面风化、结构破坏、强度衰减的主要原因。为分析盐害对大雁塔砖体结构、强度的影响机理,采用以饱和硫酸钠溶液为介质,对大雁塔砖体进行易溶盐结晶循环模拟劣化试验。在Na2SO4反复结晶、溶解过程中,测定试样的质量、波速及单轴抗压强度等指标,分析其变化规律。结果表明,在盐害作用下,试验砖体表现出与塔体表面类似的风化破坏现象;Na2SO4晶体在试样孔隙内不断发育,晶体挤压效应导致孔隙率增大,内部结构破损;质量、波速、单轴抗压强度随循环的次数呈先增加后减小的变化规律。砖体对盐害耐受力约为砖体质量的0.5%。  相似文献   
50.
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