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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.
Why do larger countries have more armed conflict? This paper surveys three sets of hypotheses put forward in the conflict literature regarding the relationship between the size and location of population groups. These hypotheses are based on population mass and concentrations, distances, and some residual state-level characteristics. The hypotheses are tested with a new dataset – ACLED (Armed Conflict Location and Events Dataset) – that disaggregates internal conflicts into individual events. The analysis covers 14 countries in Central Africa. The conflict event data are juxtaposed with geographically disaggregated data on populations, distance to capitals, borders, and road networks. The paper develops a statistical method to analyze these types of data. The analysis shows that the risk of conflict events increases with local population size, and is particularly large in highly populous locations within a country. We find only a moderate difference in conflict-proneness between areas located close to or far from a country's capital, except when combined with population concentration: Conflict events cluster particularly strongly in larger population concentrations that are distant from the capital, such as the Eastern provinces of the Democratic Republic of Congo.  相似文献   

3.
    
Under what conditions do protests occur in civil wars? Evidence from case studies suggests that protests can indeed play an important role in contexts of civil wars, with civilians using respective tactics both against the state and rebels. We argue that localities experiencing armed clashes are likely to see protest events in the same month. Civilians conduct protests due to battle-related changes in the local opportunity structures and grievances related to losses experienced through collateral damage. Using spatially disaggregated data on protest and battle events in African civil wars, we find support for our hypothesis that battles trigger civilian protests. This effect is robust to the inclusion of a comprehensive list of confounding variables and alternative model specifications, including the use of different temporal and spatial units. Our findings highlight the role of the civilian population and the spatial relationship between war events and protests in civil wars.  相似文献   

4.
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   

5.
For proponents of the view that anthropogenic climate change will become a ‘threat multiplier’ for instability in the decades ahead, the Syrian civil war has become a recurring reference point, providing apparently compelling evidence that such conflict effects are already with us. According to this view, human-induced climatic change was a contributory factor in the extreme drought experienced within Syria prior to its civil war; this drought in turn led to large-scale migration; and this migration in turn exacerbated the socio-economic stresses that underpinned Syria's descent into war. This article provides a systematic interrogation of these claims, and finds little merit to them. Amongst other things it shows that there is no clear and reliable evidence that anthropogenic climate change was a factor in Syria's pre-civil war drought; that this drought did not cause anywhere near the scale of migration that is often alleged; and that there exists no solid evidence that drought migration pressures in Syria contributed to civil war onset. The Syria case, the article finds, does not support ‘threat multiplier’ views of the impacts of climate change; to the contrary, we conclude, policymakers, commentators and scholars alike should exercise far greater caution when drawing such linkages or when securitising climate change.  相似文献   

6.
This paper investigates spatial associations between environmental change and violence in Darfur. Long-term variations in the geographical distribution of water and vegetative resources can foster migration from areas with decreasing levels of resource availability to areas with increasing levels. Rising ethnic diversity and resource competition can, in turn, escalate the risk of violence in areas of high in-migration. This paper employs a multimethod approach to investigate this hypothesis. Qualitative evidence is used to demonstrate the plausibility of the argument for the case of Darfur. The quantitative analysis is based on information retrieved from satellite imagery on long-term vegetation change and the spatial distribution of attacks on villages in the early phase of the civil war (2003–2005). The findings indicate that violence has been more likely and intense in areas that experienced increasing availability of water and vegetative resources during the 20 years prior to the civil war.  相似文献   

7.
This paper explores the practice and the political context of war rapes in the former Yugoslavia (1992-1995) and in the Greek Civil War (1946-1949). It argues that conceptions about accountability and expected gender roles may lead social actors to commit atrocities that transgress the moral codes of their own society, while condemning their victims to silence. On the other hand, a change in the political context may undermine the impunity enjoyed by the perpetrators and ultimately lead war rape victims to break their silence and bear witness. This argument is illustrated by a detailed analysis of one particular interview, in which a woman raped during the Greek Civil War decided to break her silence fifty years after the event. The interview material offers the opportunity to explore the effects of trauma and the multiple ways in which war rape victims may try to cope with past trauma and give meaning to a shattered life.  相似文献   

8.
How does violent mobilization affect post-conflict elections? This article studies the impact that violent collective mobilization has on local electoral behavior after domestic conflict. We argue that post-conflict democratic politics at the local level can be dramatically affected by local experience of civil war. The use of violence during the war and especially local political entrepreneurs who have emerged from the conflict can influence post-violent politics. We use as case-study the civil war that took place in Italy during the last phase of World War II. Using new spatially disaggregated data on armed groups' location and violent episodes, we assess the impact of the violent mobilization on the 1946 elections, which took place after the conflict. We find that partisans' mobilization and, more weakly, Nazi-Fascist violent acts influenced local politics, shifting votes towards more radical positions. Our findings hold across numerous robustness checks.  相似文献   

9.
王金虎 《史学月刊》2007,2(8):72-78
美国内战期间,南部邦联财政政策的主要目标是筹措资金。为达到此目的,南部邦联政府采取了征税和发行国库券与债券等措施。由于通过征税获得的财政收入微乎其微,南部邦联政府的财政资金便主要依靠发行国库券和债券。此举固然使得南部邦联政府短期获得一部分可支配资金,但由于南部邦联没有坚实雄厚的财政基础,又得不到外来有力的资金援助和支持,因此南部邦联财政政策并未实现既定目标,反而引发了通货膨胀和物价飞涨,加剧了南部邦联的民心涣散,最终加速了南部邦联的失败。  相似文献   

10.
    
Populations are affected by shocks of different kinds, and wars, a priori, may be among the most prominent. This article studies the effect of the Spanish Civil War (1936–1939) shock on the distribution of population, especially on cities. One of the main contributions of this study is that it underlines the importance of distinguishing between winning and losing sides, an aspect which until now has been largely overlooked. While previous research on war shocks has also tended to be concerned with inter-state wars, this paper concentrates on a civil war. We take advantage of a new, long-term, annual data set. Our results show that, overall, the Spanish Civil War did not have a significant effect on city growth. However, we also find a significant and negative effect in the growth of cities that aligned themselves with the losing side. These results are robust to heterogeneity in the effect of the war shock, measured as war severity and duration. Although short lived, the temporary effect on growth results in a permanent effect on the size of cities on the losing side.  相似文献   

11.
    
Why doesn't Africa have more self-determination movements? Given the prevalence of weak states, artificial borders, and high ethnic diversity, one might expect that the majority of African rebel groups would pursue self-determination outcomes. Yet, the data indicate that most rebel groups have attempted to capture the state in center-seeking conflicts rather than to break off a piece of it. Why? In this study, we argue that the exogenously determined territorial size of the country in which new groups emerge shapes whether groups pursue center-seeking or self-determination outcomes. We argue that the size of the territory determines the overall cohesion of the state, which then shapes the political imagination of the group, affecting how an emerging rebel group conceives of itself and its constituents relative to the state. We also argue that the size of the territory shapes the perceived feasibility of either center-seeking or self-determination outcomes. Drawing from a recent dataset on rebel group emergence, we find support that rebel groups emerging in large states are more likely to seek self-determination than rebel groups in small states. We test multiple alternative arguments and find that our results are robust to them as well as additional testing specifications.  相似文献   

12.
    
This paper introduces a new method for finding causal relationships in spatiotemporal event data with potential applications in conflict research, criminology, and epidemiology. The method analyzes how different types of interventions affect subsequent levels of reactive events. Sliding spatiotemporal windows and statistical matching are used for robust and clean causal inference. Thereby, two well-described empirical problems in establishing causal relationships in event data analysis are resolved: the modifiable areal unit problem and selection bias. The paper presents the method formally and demonstrates its effectiveness in Monte Carlo simulations and an empirical example by showing how instances of civilian assistance to US forces changed in response to indiscriminate insurgent violence in Iraq.  相似文献   

13.
The role of education in political socialisation and the importance of terrorism discourses in promoting (or silencing) certain interests have long been acknowledged. This study combines both themes by asking: How do school textbooks, sanctioned by states that are violently challenged by internal opposition, discuss the issue of terrorism? I draw on, and contribute to, four distinct, yet related streams of research: critical geopolitics, critical terrorism studies, geographies of education, and young people's geographies. Simultaneously, while most work on the topic focuses on individual cases (typically of Western countries), I conduct the first comparative analysis of twelve countries from different world regions: China, Egypt, India, Kenya, Nigeria, Papua New Guinea, Peru, Philippines, Russia, Spain, Sri Lanka and Turkey. Contrary to recent claims, considerable heterogeneity persists regarding geopolitical imaginations of terrorism, while US-coined discourses are only infrequently adapted. However, there is still recognisable functionalist convergence as the states under analysis utilise their control of the education system in their internal struggles, mainly by portraying their opponents as evil, by ascribing a positive identity to themselves, and by calling for support by their citizens (including restrictions of human rights and democracy).  相似文献   

14.
    
How do flows of internally displaced persons (IDPs) affect wartime violence? We argue that government and rebel forces respond to IDP flows in different ways, which condition where and when they employ violence. State responses are driven by the need to identify insurgents and their civilian supporters, and depend on how much information they have about where IDPs are coming from and where they are seeking to resettle. Rebel responses are driven by their need to monitor and control civilian movements, which leads to more violence against civilians in transit areas heavily trafficked by IDPs. Drawing on novel subnational data from Syria, we employ social network analysis to examine migration flow characteristics beyond aggregate IDP inflows and outflows. We find that the greater the local clustering of IDP flows – i.e., the less complex and diverse displacement movements are – the more pro-government combatants are able to detect IDPs’ origins and destinations, and the higher the number of civilian killings. Transit locations, meanwhile, become epicenters of rebel violence against civilians. While scholars have found that more information about civilian behavior causes combatants to employ more selective violence, our results suggest that more information about displacement prompts more collective violence from governments. The findings also indicate that governments respond to IDP flows after movement, whereas rebels respond to IDP flows during movement. This underscores the importance of focusing on how armed groups respond to displacement flows in order to better understand the consequences of population movements in wartime.  相似文献   

15.
    
The militarisation of conservation involves the integration of conservation, security and counterinsurgency through violent and armed strategies, or ‘war, by conservation’. We describe a militarised conservation practice in which a marine protected area was established by the state and supported by international actors in a region of ongoing ethnic and military conflict as a case of conservation, by war. Conservation and security actors actively criminalise artisanal fishing communities in Gulf of Mannar Marine National Park in India. The harvest of sea cucumbers, marine species of commercial value historically traded between the Indian state of Tamil Nadu and Sri Lanka, was banned and has become the target of militarised action. When the Sri Lankan civil war broke out in 1983, sea cucumber trade turned into a security concern as the same sea routes were also being used for trafficking arms, ammunition, and other contraband. Tamil Nadu was geographically and logistically involved in the civil war due to ethnic ties. The Sri Lankan civil war and its social and political consequences on the neighbouring state of Tamil Nadu due to ethnic ties is a fitting case of the nexus of conservation and security in a marine context. Based on ethnographic fieldwork and interviews conducted with artisanal fishers and conservation and security actors, we show that violent political conflict provided the justification for securitisation of conservation. As the state focuses its conservation efforts on the marine protected area, commercial fisheries detrimental to fisheries and biodiversity conservation continue. Marine protected areas allow the state to achieve its security outcomes even as it fails to meet its conservation goals due to non-local drivers of declines in species populations. Trans-boundary marine environments are particularly difficult to govern due to the dynamic nature of the seascape. The materiality of the sea and the conservation-security nexus results in the creation of a violent maritime space.  相似文献   

16.
    
As information networks catalyse local incidents into international crises, as global events appear and disappear on multiple screens at an accelerated pace and as a war of images displaces the image of war, it becomes increasingly difficult to understand the rapidly changing nature of global violence within the confines of security studies. Phase-shifting with each media intervention from states to sub-states, local to global, public to private, organised to chaotic and virtual to real—and back again—global violence superpositions into a quantum war that requires new transdisciplinary, transnational and transmedial approaches.  相似文献   

17.
Abstract

Abraham Lincoln's presidency was defined and dominated by war, yet Lincoln himself had very little direct experience with warfare; nor had the American presidency been truly tested by war when he took office. Lincoln had to negotiate very difficult political and constitutional terrain as he waged the Civil War: issues of executive authority, constitutional powers and their limitations, and the nature of civil liberties during war constantly bedeviled him. His guiding principle in all these matters, and the greatest lesson we can learn from him today, was his flexibility and his pragmatism.  相似文献   

18.
This paper examines the spatial transmission and rate of propagation of three infectious diseases (enteric fever, smallpox and yellow fever) in times of war and peace in Cuba between 1895 and 1898. For the three diseases studied, the analysis will demonstrate that, compared with peacetime, the Cuban Insurrection caused increased epidemiological integration of the settlement system of Cuba, acceleration of the spatial processes of disease transmission and a marked change in the geographical drift of infectious disease activity. While the first two findings may be attributed to the heightened levels of population mixing that accompanied the insurrection, the third implies that hostilities fundamentally altered the spatial courses of diseases. These changes transcended stark biases in the predisposition to infection among Spanish soldiers (to yellow fever) and Cuban civilians (to smallpox). Finally, it is shown that the military were the prime agents causing contrasts in the epidemiological experience of Cuba between war and peace.  相似文献   

19.
    
Tree‐ring dating involves matching sequences of ring widths from undated timbers to dated sequences known as ‘master’ chronologies. Conventionally, the undated timbers (from a building or woodland) are sequentially matched against one another, using t‐tests to identify the relative offsets with the ‘best’ match, thus producing a ’site’ chronology. A date estimate is obtained when this is matched to a local master chronology of known calendar age. Many tree‐ring sequences in the UK produce rather low t‐values and are thus declared not to have a ‘best’ match to a master chronology. Motivated by this and the routine use of Bayesian statistical methods to provide a probabilistic approach to radiocarbon dating, this paper investigates the practicality of Bayesian dendrochronology. We explore a previously published model for the relationship between ring widths and the underlying climatic signal, implementing it within the Bayesian framework via a simulation‐based approach. Probabilities for a match at each offset are produced, removing the need to identify a single ‘best’ match. The Bayesian model proves successful at matching in both simulated and real examples.  相似文献   

20.
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