37 research outputs found

    Swiss Standards for Existing Structures

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    In January 2011, the Swiss Society of Engineers and Architects (SIA) published a series of standards for existing structures. The standard entitled 'existing structures-bases for examination and interventions' specifies the principles, the terminology and the appropriate methodology for dealing with existing structures. This standard is complemented by a series of standards which treat specific items regarding 'actions on existing structures', 'existing concrete, steel, composite, timber and masonry structures' as well as 'geotechnical aspects of existing structures'. It is expected that these standards will provide effective solutions on questions such as higher live loads, accidental actions or the restoration and improvement of the durability of existing structures. This paper highlights major principles, in particular those related to risk-based safety, proportionality of interventions and updating of variables. Methodological aspects of the main activities, that is, examination of structures and intervention measures, are described

    New European Technical Rules for the Assessment and Retrofitting of Existing Structures.

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    The consideration of sustainability aspects in the construction sector jointly with considerable economic interests have been the main impulse to include the work item of assessment and retrofitting of existing structures in the Mandate M/515 with a high priority. The new European technical rules will be developed using the existing organization of CEN/TC250. The present report has been worked out in the frame of CEN/TC250/WG2 activities. The report encompasses: Part I introduces the policy framework and the CEN/TC250 initiative. Part II is a collation of the different existing National regulations and standards in Europe with regard to existing structures. Part III gives a prospect for CEN guidance for the assessment and retrofitting of existing structures. Having in mind the stepwise procedure for preparation of CEN Technical Documents, the contents of Part III is broader, covers more aspects, and includes more information than the normative technical recommendations. In particular, key issues are identified that require resolution and a summary of different national perspectives is provided rather than seeking to resolve all difficult technical issues during the first work step. The report presents scientific and technical background intended to stimulate debate and serves as a basis for further work to achieve a harmonized European view on the assessment and retrofitting of existing structures.JRC.G.4-European laboratory for structural assessmen

    Valuing flood disasters using the life satisfaction approach

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    This paper argues that life satisfaction data can be used to value natural disasters. We discuss the strengths of this approach, compare it to traditional methods and apply it to estimate and monetize utility losses caused by floods in 16 European countries between 1973 and 1998. Using combined cross-section and time-series data, we find a negative impact of floods on life satisfaction that is sizeable, robust and significant. The estimates are comparable to price discounts found in housing markets. In an exploratory analysis, we find that risk transfer mechanisms such as mandatory insurance have large mitigating effects

    EEG-fMRI Signal Coupling Is Modulated in Subjects With Mild Cognitive Impairment and Amyloid Deposition

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    Cognitive impairment indicates disturbed brain physiology which can be due to various mechanisms including Alzheimer's pathology. Combined functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) recordings (EEG-fMRI) can assess the interplay between complementary measures of brain activity and EEG changes to be localized to specific brain regions. We used a two-step approach, where we first examined changes related to a syndrome of mild cognitive impairment irrespective of pathology and then studied the specific impact of amyloid pathology. After detailed clinical and neuropsychological characterization as well as a positron emission tomography (PET) scans with the tracer 11-[C]-Pittsburgh Compound B to estimate cerebral amyloid deposition, 14 subjects with mild cognitive impairment (MCI) (mean age 75.6 SD: 8.9) according to standard criteria and 21 cognitively healthy controls (HCS) (mean age 71.8 SD: 4.2) were assessed with EEG-fMRI. Thalamo-cortical alpha-fMRI signal coupling was only observed in HCS. Additional EEG-fMRI signal coupling differences between HCS and MCI were observed in parts of the default mode network, salience network, fronto-parietal network, and thalamus. Individuals with significant cerebral amyloid deposition (amyloid-positive MCI and HCS combined compared to amyloid-negative HCS) displayed abnormal EEG-fMRI signal coupling in visual, fronto-parietal regions but also in the parahippocampus, brain stem, and cerebellum. This finding was paralleled by stronger absolute fMRI signal in the parahippocampus and weaker absolute fMRI signal in the inferior frontal gyrus in amyloid-positive subjects. We conclude that the thalamocortical coupling in the alpha band in HCS more closely reflects previous findings observed in younger adults, while in MCI there is a clearly aberrant coupling in several networks dominated by an anticorrelation in the posterior cingulate cortex. While these findings may broadly indicate physiological changes in MCI, amyloid pathology was specifically associated with abnormal fMRI signal responses and disrupted coupling between brain oscillations and fMRI signal responses, which especially involve core regions of memory: the hippocampus, para-hippocampus, and lateral prefrontal cortex.ISSN:1663-436

    Why does unemployment hurt the employed? Evidence from the life satisfaction gap between the public and the privat sector

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    High rates of unemployment entail substantial costs to the working population in terms of reduced subjective well-being. This paper studies the importance of individual economic security, in particular job security, in workers’ well-being by exploiting sector-specific institutional differences in the exposure to economic shocks. Public servants have stricter dismissal protection and face a lower risk of their organization’s bankruptcy than private sector employees. The empirical results for individual panel data for Germany and repeated cross-sectional data for the United States and the European Union show that the sensitivity of subjective well-being to fluctuations in unemployment rates is much lower in the public sector than in the private. This suggests that increased economic insecurity constitutes an important welfare loss associated with high general unemployment

    Disaster, Aid, and Preferences: The Long-run Impact of the Tsunami on Giving in Sri Lanka

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    Do natural disasters produce effects on preferences of victims in the long run? We test the impact of the tsunami shock on generosity of a sample of Sri Lankan affected/unaffected microfinance borrowers seven years after the event.Specifically, we test the effect of the shock at the extensive margin by comparing damaged with non-damaged individuals in terms of giving and expected giving in a dictator game. Moreover, at the intensive margin, we compare the participants based on the amount of damage experienced and recovery aid received. The advantage of this last comparison is that differences in observables between the groups are minimized. We reduce further identification problems by selecting a random sample of damaged and non-damaged borrowers belonging to the same microfinance organization who are, therefore, likely to share some important common traits that are usually unobservable to researchers. We complete our identification strategy with weighted least squares, instrumental variable estimates and a sensitivity analysis on the exogeneity assumption.The main findings of the paper support the hypothesis that the shock affects participants' preferences in the long run. First, the tsunami negatively affects generosity at the extensive margin as those who suffered at least one damage give and expect less than those who did not. Second, while large recovery assistance does not directly affect giving and expected giving, it increases especially the latter indirectly, i.e., when interacted with the number of damages.Our results reconcile that part of the literature showing evidence of natural shocks having a detrimental effect on social preferences (Fleming, Chong, Alberto, & Bejarano, 2011; Cassar, Grosjean, & Whitt, 2013) with that supporting, instead, a positive link (Solnit, 2009; Whitt & Wilson, 2007; Cassar, Healy, & Von Kessler, 2011). Furthermore, since our study focuses on the long-run impact of a natural disaster, previous results on short-run effects are not necessarily inconsistent with ours

    Valuing Public Goods: The Life Satisfaction Approach

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    "This paper discusses a novel approach to elicit people's preferences fornpublic goods, namely the life satisfaction approach. Reported subjective well-beingndata are used to directly evaluate utility consequences of public goods. The strengthsnof this approach are compared to traditional approaches and identification issues arenaddressed. Moreover, it is applied to estimate utility losses caused by terroristnactivities in France, the UK and the Republic of Ireland. Terrorism in these countriesndepresses life satisfaction in a sizeable and robust way. However, the calculation ofnthe trade-off between terrorism and income requires improved measurement of thenmarginal utility of income.
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