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1.
Mark Blackham 《Journal of Archaeological Method and Theory》1998,5(2):165-207
The primary objective of relative dating techniques is to determine a reliable sequence of archaeological deposits. This task
becomes more difficult whenever our research steps beyond individual sites to the study of intercommunity relationships because
we need to develop some means of associating unconnected deposits in time. Radiocarbon dating, as a stand-alone method, cannot
always be used to draw reliable correlations between sites. The relevance of archaeological dates, including absolute dates,
relies ultimately on the determination of artifact or sample associations and their respective superpositional relationships.
The Unitary Association Method of Relative Dating is an alternative to seriation methods that is less susceptible to spatial
variation and offers analytical strengths needed for regional chronological analyses. 相似文献
2.
Xinzheng Lu Yuan Tian Song Cen Hong Guan Linlin Xie Lisha Wang 《Journal of Earthquake Engineering》2018,22(9):1662-1682
Shear walls are important lateral force-resistant components of tall buildings. Hence, a reliable numerical model that can accurately represent the mechanical characteristics and large deformations of shear walls is critical for realistic collapse simulation of tall buildings. Based on the theory of generalized conforming element, a high-performance quadrilateral flat shell element, NLDKGQ, accounting for the large deformation using the updated Lagrangian formulation, is proposed herein and implemented in OpenSees. The reliability of NLDKGQ is validated using classical benchmark problems and reinforced concrete specimens. In addition, its capability in simulating the collapse of a tall building is also demonstrated. 相似文献
3.
Solution strategies are presented to address three potential problems in the empirical derivation of fragility functions from empirical data using the maximum likelihood method. The first strategy addresses the case of fragility curves that cross, the second strategy incorporates demand uncertainty in fragility derivation from post-earthquake reconnaissance data, and the third strategy provides a framework for the resolution of conflict between empirical data and expert opinions. The advantages and disadvantages of the proposed solution strategies are discussed and their use is demonstrated by way of suitable illustrative examples. 相似文献
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In this paper, the Member Discrete Element Method (MDEM) is modified and perfected for three aspects: the algorithm itself, loading and computational efficiency, and to accurately and quantitatively simulate the progressive collapse for large-span spatial steel structures. In addition, the corresponding computational programs are compiled. First, from the perspective of the method, a meshing principle for discrete element models is determined, a treatment for material nonlinearity and strain rate effect is proposed, and a damping model is established. Next, the Displacement Method is introduced to determine the multi-support excitation for the MDEM, and then motion equations of particles under multi-support excitation are derived. On this basis, the specific process of gravitational field loading is presented. Furthermore, parallel implementation strategies for the MDEM based on OpenMP are constructed. Finally, the collapse simulation of a 1/3.5-scaled single-layer reticulated dome shaking table test model under multi-support excitation is carried out. The comparison demonstrates that the ultimate load and failure mode as well as the complete collapse time of the numerical results are consistent with the experimentally measured responses, and the configuration variations from member buckling and local depression until collapse failure are fully captured. Moreover, the displacement time-history curves obtained using MDEM are almost identical to the experimental measurements, and there is a nuance only in the amplitude. It is verified that MDEM is capable of precisely addressing the collapse failure for large-span spatial steel structures. Additionally, the failure mechanism for structures of this type is naturally revealed. 相似文献
6.
Numerous local, regional and family historians in the nineteenthand early twentieth century collected oral narrations and conductedinterviews as a form to document information that otherwisemight have never been preserved. Family historians, in particular,not only practiced interviewing relatives for family histories,but also encouraged the practice in how-to-do manuals amongtheir peers. While advocating the practice, family historiansalso reflected about the value of "traditionary evidence" collectedthrough interviews and other means. These reflections by familyhistorians mirrored the discussions about the value of traditionsand memories as historical sources among several professionalhistorians at the time. These reflections were shaped by a modernizedunderstanding of tradition, which combined a reverential approachto the authoritarian element of tradition with a critical approachquestioning the validity of tradition. In this context, oralhistory was both a tool to negotiate the value of traditionand a mirror to the contemporary understanding of tradition. 相似文献
7.
James H. Barrett 《International Journal of Osteoarchaeology》1993,3(1):1-18
Past approaches to the Weight Method (use of the weight of excavated bone assemblages to evaluate the relative potential meat yield of the animals from which they came) are critically reviewed. They do not account for both inter-taxon and intra-taxon variability in the relationship between bone weight and total body or soft tissue weight. Critics of the Weight Method have assumed that these problems are insurmountable. It is argued here that they can be overcome practically. Solutions lie in the integration of classic Weight Method approaches, which assume a consistent ratio of bone weight to body weight between different taxonomic and size groups, with the understanding of animal scaling provided by studies of skeletal mass allometry. Allometric equations derived from original data (regarding cod, Gadus morhua) and available from published sources (regarding mammals and birds) are used to illustrate this argument. Three practical approaches to the Weight Method are suggested and briefly explored, using bone weight data from Earls' Bu, a Norse site in Orkney, Scotland, as a case study. 相似文献
8.
Ahmad Fathi Arjang Sadeghi M. R. Emami Azadi 《International Journal of Architectural Heritage》2020,14(6):795-810
ABSTRACTHistoric heritage buildings are a part of historic basis of each society and an economic resource. Therefore, preserving and maintenance of these buildings are cultural, economic and social demand. This research investigates the seismic performance of a historical building named Arg of Tabriz (Arge Alishah) that dates back to 14th century and is located at the city center of Tabriz (NW of Iran). Static, modal, and finally nonlinear dynamic (time history) analysis were performed by both “Considering Soil-Structure Interaction (SSI)” and “fixed base (ignoring SSI)” Cases.It is found from the results that, SSI extremely affects mode shapes and their frequencies and depending on the frequency content of the records, can has an incremental or decremental effect on structural responses. As expected, the building of Arg could carry gravity loads easily and despite its stability against earthquake loading in fixed base case, showed a weakness (especially in eastern and western walls direction) and overturned when it was analyzed in SSI case because of yielding of the surrounding soil. 相似文献
9.
Michael Quinn 《History of European Ideas》2017,43(1):11-33
ABSTRACTThe goal of this paper is to locate indirect legislation within Bentham’s art of legislation, and to distinguish it, as far as possible, from direct legislation. Along the way, some parallels are drawn between indirect legislation on the one hand, and the Nudge theory of Thaler and Sunstein on the other. It will be argued that many expedients categorized by Bentham as indirect legislation are simultaneously exercises of direct legislation. Another set of indirect expedients act on knowledge, and involve efforts to eliminate asymmetries of information between potential offender and potential victim by providing official standards and disseminating a plethora of factual information. Other forms of indirect legislation threaten the coherence of Bentham’s theory of law, firstly by regarding all government actions as exercises in legislation, and secondly by turning the formers of public opinion into legislators. Insofar as some forms of indirect legislation operate by sleight of hand, they conflict with Bentham’s commitment to transparency in the exercise of public power, reflecting a tension between reality and appearance which runs through his thought. 相似文献
10.
In this article, a Simulink simulation block with the finite element function is developed on the basis of S-function and implemented as the numerical substructure of real-time dynamic hybrid testing. Thereby, a real-time dynamic hybrid testing system coupling finite element calculation and shaking table testing is achieved. Using the developed system, a shear frame mounted on the soil foundation is tested, in which the shear frame is simulated as the physical model and the foundation is simulated as the finite element model with 132 degrees of freedom. Several cases of the dynamic behavior of soil-structure interaction are studied. 相似文献