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1.
    
When it comes to existing buildings, the estimation of the structural residual bearing capacity is required to evaluate the potential for reuse/conversion. The level of detail and accuracy of surveys dramatically affect structural diagnostics. In order to optimise the experimental survey process, a simulation of the structural life-cycle may be useful.

Based on a previously developed approach of Monte Carlo simulation implemented with a damage law for the life-cycle analysis of newly designed constructions, this paper presents the method application to a historic roof steel structure. It aims to identify critical situations, assess the residual life of the system, and plan possible retrofit strategies for the building conversion.

The case study is a steel frame roof structure of the ex pig abattoir within the complex of the municipal slaughterhouse in Monza (close to Milan, Northern Italy) and protected from the Cultural Heritage Authority. The life-cycle of the structure is here investigated over different stages of the building lifespan along with the damages caused by aging and negligence. The construction was built in 1902, and abandoned in 1984. Therefore, the periods analysed are: from construction to disuse and from disuse to today. The second phase of life, still on going, has significantly sped up the degradation.

The probabilistic evaluation of failure times is discussed and the possible interventions scenarios in terms of costs, and after-maintenance reliability and safety are investigated.  相似文献   


2.
Recent growth in the number of school choice programs across the country has ignited debate on the stratifying effects of these programs. In the context of interdistrict open enrollment, this paper analyzes—both theoretically and empirically—how choice programs affect stratification levels through the mechanisms of (i) the relative characteristics of program participants and nonparticipants and (ii) the schooling choices of different groups of program participants. The theoretical analysis uses Monte Carlo simulation techniques to analyze a hypothetical world where interdistrict choice is available to students in three school districts that are allowed to vary in student composition, the type of students who take advantage of the interdistrict choice program, and schooling choices of students who open enroll. The results of these simulations provide an understanding of the conditions under which an interdistrict open enrollment program leads to increases, decreases, or no changes in stratification levels. The empirical analysis uses data from the universe of students attending Colorado public schools in 2009–10 to examine how the state's interdistrict choice program affects stratification levels. It also analyzes the factors responsible for any increases or decreases in stratification and finds both participation patterns and differences in schooling decisions across groups to play important roles. The paper concludes with a discussion of its implications for research and policy.  相似文献   

3.
4.
    
At the time of the discovery of the Newport medieval ship, it proved impossible to date the timbers used in its original construction through dendrochronology. Associated British timbers and artefacts provided dating to the mid 15th century, with the latter pointing to strong Iberian connections. The development of regional oak ring‐width chronologies in the Basque Country, and their extension back in time to overlap with the ring‐width mean developed for the Newport Ship, has allowed absolute dating and provenance of timbers used in its original construction. Further research is required to clarify the geographical source of the timbers and to develop a high‐resolution network of tree‐ring data for the region.  相似文献   

5.
  总被引:1,自引:0,他引:1  
Much of the current conflict literature attempts to explain the occurrence of violence as the result of determinants exogenous to the conflict process. This paper takes a different approach and analyzes how violence in civil wars spreads in space and time, drawing on earlier work on micro-diffusion of violence in criminology as well as high resolution conflict data. Two general scenarios are distinguished in our analysis: the relocation and the escalation of conflict. Relocation diffusion corresponds to a shift in the location of violence, whereas escalation diffusion refers to the spatial expansion of the conflict site. We argue that unconventional warfare in civil wars without demarcated front lines should primarily lead to the second type of pattern. We describe an extension to a joint count statistic to measure both diffusion types in conflict event data. Monte Carlo simulation allows for the establishment of a baseline for the frequency of contiguous conflict events under the assumption of independence, and thus provides a significance test for the observed patterns. Our results suggest that violence in civil wars exhibits patterns of diffusion, and in particular, that these patterns are primarily of the escalation type, driven by the dynamic expansion of the scope of the conflict.  相似文献   

6.
This paper provides the results of the dendrochronological analyses of seven wood samples from the Ottoman fortress of Seddülbahir on the Gallipoli Peninsula or Turkey. It concludes that the trees were cut in the late spring of 1656. The data collected allows the first building phase of the fortress to be securely dated. By bringing together the dendrochronological results with various archival records about the fortress, a more precise building chronology for the fortress can be reconstructed. The probable initial period of construction was between 1656 and 1661.  相似文献   

7.
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   

8.
As part of a research project on medieval trade and maritime transportation in the former Norwegian province of Bohuslän, western Sweden, a dendrochronological analysis of the so‐called Mollö cog was undertaken. The wreck, which was first salvaged in 1980, was previously dated by 14C analysis. Since this provided a nearly 400‐year time‐span for the building of the vessel, a more precise dating was considered essential. In conjunction with dendrochronological sampling, several features not previously reported were recorded. This paper presents the find, the research history and the results of the dendrochronological investigation. © 2012 The Authors  相似文献   

9.
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   

10.
    
This paper examines the possibilities of creating quantified models of past human activities in both time and space. The study area lies in the south‐eastern Czech Republic and western Slovakia. The spatio‐temporal model of behavioural categories was calculated with the help of Monte Carlo simulations and statistical testing. One of the main advantages of our approach is that it admits the probabilistic nature of input data, quantifies them and provides probabilistic results comparable with other proxies. It also presents a less biased way of how archaeological data from regions and periods with low numbers of 14C datings can be incorporated into models of past population dynamics.  相似文献   

11.
Exchanges of material objects often play a pivotal role in the trajectories of political, social, and economic development for ancient societies, but the study can be challenging because of the complexity of exchange. Multiple forms of exchange co-exist in ancient societies including market exchange and social exchange such as gift-giving. A further complicating factor is that different exchange systems such as redistribution and central place market exchange can result in the same regional spatial patterning of artifacts. Recent innovations in identifying exchange systems use network expectations for spatial, contextual, and distributional information to help distinguish between social exchanges such as gift-giving versus market exchange using household inventories. I introduce a Monte Carlo computer simulation to evaluate network expectations for alternative exchange mechanisms, using a case study of decorated ceramics from 65 residential inventories from the center of Sauce and its hinterland during the Middle Postclassic period (1200–1350 A.D.) in southcentral Veracruz, Mexico. Using these new tools, I identify the coexistence of several exchange systems operating simultaneously. The methods developed here demonstrate the potential of using network expectations to refine existing methods to identify different exchange systems that can be applied to other complex ancient economies.  相似文献   

12.
    
The period around 50 000–35 000 years ago constitutes one of the most debated research issues in European archaeology of the Palaeolithic. In this time period, the transition from the Middle to the Upper Palaeolithic took place. Locally, in different areas of Europe, this shift is recorded in so‐called transitional assemblages. The eastern fringe of these transitional assemblages is represented by the Jerzmanowician, the unit described on the basis of a lithic assemblage from Nietoperzowa Cave (Poland). The unit is a part of a European transitional complex called the Lincombian–Ranisian–Jerzmanowician. Up to now, the radiocarbon dates presented in the literature have only allowed us to set the age of the Jerzmanowician at c.40 000–45 000 ka cal bp . In this study, we present 42 new radiocarbon dates. We attempt to set the archaeological record of the Jerzmanowician from Nietoperzowa Cave in an accurate chronological framework, based on Bayesian statistical processing of radiocarbon dates. We conclude that the lower boundary of layer 6 in Nietoperzowa Cave can be statistically located in the range 44 000–42 000 cal bp and the upper limit for the Jerzmanowician is estimated to c.31 000 cal bp . New data raises a question on the correlation with upper layer 4. In the light of the new chronology, the attribution of the archaeological inventory from layer 4 to the Jerzmanowician seems questionable.  相似文献   

13.
    
The Malara (Anuru Bay A) Macassan trepang‐processing site was investigated from 2008 to 2010, to test two chronological models of the timing of cultural contact between north‐west Arnhem Land and South‐East Asia. Currently, the models of contact between South‐East Asian people and Australian Indigenous people are a “long model” of pre‐Macassan and Macassan contact (>200 years) and a “short model” of only Macassan contact (<120 years). The aims of this study were to assess when the site was first occupied, when intensification of site use occurred and when the site was abandoned. This assessment was undertaken by radiocarbon dating of the major trepang‐processing features, the two burials at the site and several other occupation areas. Bayesian analysis of the 18 radiocarbon dates gives 80% probability that Indonesians first used the site around AD 1637. Trepang processing intensified during the middle to late eighteenth century, consistent with the known expansion of the Macassan trepang trade. There is a final occupation and processing phase in the late nineteenth century. We discuss issues regarding the “old” radiocarbon dates from trepang‐processing sites. We argue that our investigations support the “long model” of cultural contact between Asian visitors and local Indigenous groups.  相似文献   

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