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81.
Graphic and metric information about the site and its environment and about the different structures and artefacts located are indispensable for the optimal management of an archaeological excavation. A Geographic Information System (GIS) proves useful in managing and analysing information and data obtained from different sources. Two techniques of data capture, Terrestrial Laser Scanning (TLS) and close range photogrammetry, are used to generate accurate and high-resolution 3D models of a cave, the silos and a combustion structure at the Can Sadurní site (Begues, NE Spain). This site is especially noteworthy on account of its complete stratigraphy of the Catalonian Holocene. The capture and processing of the photogrammetric and TLS data used to generate 3D models are discussed in detail. These models cannot be obtained by classic archaeological techniques since the record is made layer by layer, approximately one decimetre apart, with the result that the information between the layers is lost. Our findings highlight the potential of these techniques for obtaining accurate and photorealistic models that facilitate a complete analysis of the available information at an archaeological site.  相似文献   
82.
The modelling of past settlement and landscape structure from incomplete evidence is a well-established archaeological agenda. This paper highlights a model of spatial interaction and settlement evolution that has long been popular in urban geography and which was first applied to model historical settlement hierarchies some twenty-five years ago, but whose use since then for archaeological purposes has been very limited. Via a case study from Bronze Age Crete, we extend the analytical range of this model by suggesting ways in which it can (a) remain effective in the presence of missing data, (b) be given a stronger grounding in the physical landscape, and/or (c) be used to consider the evolutionary trajectory of settlements and physical routes over time.  相似文献   
83.
Three Santacrucian borhyaenoids, Cladosictis patagonica, Pseudonotictis pusillus and Sipalocyon gracilis, are analyzed from a functional-adaptive perspective. Five extant placentals and one marsupial model are also examined in order to interpret the locomotor adaptations of these fossils. Pseudonotictis pusillus is the smallest of the Santacrucian borhyaenoids and is known from fragmentary remains; from its small size, dental specializations and elbow anatomy, this species was certainly not far ecologically from an extant weasel. The postcranium of Sipalocyon gracilis, although poorly known, suggests climbing capabilities, and the pseudo-opposable pollex indicates skilful manipulative behaviour. Cladosictis patagonica was an active predatory form, short-legged and able to climb, although it was a less specialized arboreal form than the contemporaneous Prothylacinus patagonicus; the proportions of its limbs recall that of a living South American marten, the tayra. The pseudo-opposable pollex of Cladosictis, as in Sipalocyon, indicates skilful manipulative behaviour.  相似文献   
84.
To analyze social network data using standard statistical approaches is to risk incorrect inference. The dependencies among observations implied in a network conceptualization undermine standard assumptions of the usual general linear models. One of the most quickly expanding areas of social and policy network methodology is the development of statistical modeling approaches that can accommodate such dependent data. In this article, we review three network statistical methods commonly used in the current literature: quadratic assignment procedures, exponential random graph models (ERGMs), and stochastic actor‐oriented models. We focus most attention on ERGMs by providing an illustrative example of a model for a strategic information network within a local government. We draw inferences about the structural role played by individuals recognized as key innovators and conclude that such an approach has much to offer in analyzing the policy process.  相似文献   
85.
The principal aim of this work is to investigate whether protein sources in human diets in early Anglo-Saxon (5th-7th century AD) England varied with geographic location, or with respect to age or sex. The methodology used was analysis of δ15N and δ13C in human bone collagen from 76 adult skeletons from a total of 18 different cemeteries located in inland, riverine and coastal environments. In order to control for the possible effects of socio-economic status on diet, only high status individuals, as identified by grave goods, were studied. Data were analysed using statistical manipulation of the raw results and using IsoSource (Phillips and Gregg, 2003), a mathematical treatment which models the composition of the protein part of human diets using bone stable isotope ratios when the isotopic values for potential protein sources are known or can reasonably be inferred. The results suggest that protein sources varied little according to geographic location and that terrestrial foods dominated at all locations. However there were some subtle patterns. Slightly elevated δ13C in skeletons from coastal locations, and δ15N in those from riverine sites may indicate that communities in these locations made greater use of marine and freshwater resources respectively. If this is correct then it demonstrates that 5th-7th century communities made some use of wild resources even within a predominantly agrarian economy. In general the analysis of the raw data and the IsoSource results were mutually supportive, and this work demonstrates the value of this twin-pronged approach to analysis of human bone stable isotope data.  相似文献   
86.
Under what conditions do citizens demand punishment of corrupt government officials or actions? Citizens' demands complement and motivate government actions. Studies suggest, however, that citizens' demands are weak and not credible. This paper considers that credible demands are the outcomes of strategic interaction between citizen groups. The results from experimental surveys in Australia and the United States show citizens' demands are credible across various conditions, including size of participants or groups, and regardless of whether they suffer losses from corruption, or whether other participants suffer losses from corruption. This paper makes three contributions. Firstly, it delineates a theoretical model that predicts concerted action. This is a useful alternative to extant treatments that generally report outcomes where coordination problems and free-ridership undermine citizens' concerted action and credibility. Secondly, experimental results clarify several conditions under which citizens' demands are credible, that is, when citizens act in concert to demand punishment. Thirdly, the consistent results across Australia and the US where individualism is high provide useful baselines for further studies.

公民们在什么情况下会要求惩治腐败的政府官员和腐败行为?研究证明,公民的要求虚弱而不可靠。本文认为可靠的要求来自公民群体间的战略互动。澳大利亚和美国的实验调查表明,公民的要求可靠与否取决于诸如参与者或群体规模等条件,而不论他们是否从腐败中受损,或别人是否从腐败中受损。本文有以下三点贡献。第一,勾画了预测腐败的模型。目前的方法报告了协调问题和免费搭车消弱公民协调行动和工信度的结果。该模型可为替代方法。第二,实验结果表明在一些情况下公民的要求是可靠的,那就是,当公民协调一致要求惩治腐败的时候。第三,个人主义发达的澳大利亚和美国的调查结果可以成为进一步研究的基点。  相似文献   
87.
A continuous damage model and different simplified numerical strategies are proposed to simulate the behaviour of reinforced concrete (R/C) walls subjected to earthquake ground motions. For 2D modelling of R/C walls controlled primarily by bending, an Euler multilayered beam element is adopted. For 3D problems, a multifibre Timoshenko beam element having higher order interpolation functions has been developed. Finally, for walls with a small slenderness ratio we use the Equivalent Reinforced Concrete model. For each case, comparison with experimental results of R/C walls tested on shaking table or reaction wall shows the advantages but also the limitations of the approach.  相似文献   
88.
In the search for robust constitutive models suitable for reproducing the performance of bridge piers during a seismic event, this paper details the simulation of the cyclic responses of four rectangular hollow section R/C bridge piers. These four R/C bridge piers were built at scale 1/2.5 and tested experimentally. Both tall and short piers are considered, covering situations where bending or shear are of relevance. Furthermore, the four piers were reinforced according to rather different design strategies: (I) the first is a 30-year-old bridge designed without allowance to the seismic action, and (ii) the second is a bridge fulfilling the EC8 provisions. The detailed constitutive model that provides the numerical predictions includes two submodels: one with two scalar damage variables, reproducing the tensile and compressive degradations of concrete, and the other is based on the Giuffre-Menegotto-Pinto formulation, simulating the cyclic behaviour of the re-inforcement. The Damage Mechanics submodel is implemented at the Gauss points of the finite elements that discretize the concrete, whereas the steel submodel is implemented on the 2-noded truss elements adopted for the rebars. A comparison between the numerical and the experimental results is discussed in detail in this paper.  相似文献   
89.
The primary focus of a structural shake table system is the accurate reproduction of acceleration records for testing. However, many systems deliver variable and less than optimal performance, particularly when reproducing large near-field seismic events that require extreme table performance. Improved identification and control methods are developed for large hydraulic servo-actuated shake table systems that can exhibit unacceptable tracking response for large, near-field seismic testing. The research is presented in the context of a 5-tonne shake table facility at the University of Canterbury that is of typical design. The system is identified using a frequency response approach that accounts for the actual magnitudes and frequencies of motion encountered in seismic testing. The models and methods developed are experimentally verified and the impact of different feedback variables such as acceleration, velocity and displacement are examined.

The methods show that shake table control in testing large near-field seismic events is often a trade off between accurate tracking and nonlinear velocity saturation of the hydraulic valves that can result in severe acceleration spikes. Control methods are developed to improve performance and include both acceleration and displacement feedback to reduce the acceleration spikes, and record modification, where the reference signal is modified to conform to the shake table's operational parameters. Results show record modification gives exact tracking for near-field ground motions, and optimal system response for reference signals with velocity components greater then the system capabilities. Overall, the research presents a methodology for simple effective identification, modelling, diagnosis and control of structural shake table systems that can be readily generalised and applied to any similar facility.  相似文献   
90.
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