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51.
Jairo A. Valcárcel Miguel G. Mora Omar D. Cardona Lluis G. Pujades Alex H. Barbat Gabriel A. Bernal 《Natural Hazards》2013,69(1):845-868
This article presents a methodology for an estimate of the benefit cost ratio of the seismic risk reduction in buildings portfolio at broadscale, for a world region, allowing comparing the results obtained for the countries belonging to that region. This methodology encompasses (1) the generation of a set of random seismic events and the evaluation of the spectral accelerations at the buildings location; (2) the estimation of the buildings built area, the economic value, as well as the classification in structural typologies; (3) the development of vulnerability curves for each typology; (4) the estimation of the annual average loss of the buildings portfolio in the current conditions as well as in the case of a hypothetical structural intervention. The benefit cost ratio is estimated as the difference between the estimates of the present value of these two annual average losses, divided by the retrofitting costs. This methodology has been applied to the portfolio of public schools of 14 countries of Latin America and the Caribbean, for evaluating the feasibility of the seismic risk reduction at a national scale. 相似文献
52.
Mineralogy and Petrology - The Berlins Porphyry located on the South Island of New Zealand provides an opportunity to examine iron concretions formed in a subterranean system. Specifically, an... 相似文献
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54.
Modeling Wing Crack Extension: Implications for the Ingredients of Discrete Element Model 总被引:1,自引:0,他引:1
In this study, we investigate what basic mechanisms a Discrete Element Model should have in order to reproduce the realistic wing crack extension, a widely observed phenomenon in uni-axial compression of brittle material with pre-existed crack. Using our Discrete Element Model—the Lattice Solid Model, we study how cracks propagate when different force-displacement laws are emplyed. Our results suggest that the basic features of crack propagation observed in laboratories cannot be reproduced under the following circumstances: 1) When only normal forces between two bonded particles exist and particle rotation is prohibited; 2) normal and shear stiffnesses are present and particle rotation is prohibited; 3) normal, shear stiffnesses and particle rotation are present and bending (rolling) stiffness is absent. Only when normal, shear and bending stiffness exist and particle rotation is permitted, is it possible to reproduce laboratory tests. We conclude that particle rotations and rolling resistance play a significant role and cannot be neglected while modeling such phenomenon. The effects of friction in the crack plane and confining pressure on extension of the cracks are also discussed. 相似文献
55.
Due to deleterious effects on non-target organisms, the use of organotin compounds on boat hulls of small vessels (<25 m) has been widely prohibited. The International Maritime Organisation (IMO) resolved that the complete prohibition on organotin compounds acting as biocides in antifouling systems should commence in 2008. As a result of restrictions on the use of organotin based paints, other antifouling formulations containing organic biocides have been utilised. This survey was conducted to assess the contamination of replacement biocides in the marine environment following the ban of TBT-based paints. Surface sediments samples were collected in the major ports and marinas along the France Mediterranean coastline (Cote d’Azur) and analysed for organotin compounds, Irgarol 1051, Sea-nine 211TM, Chlorothalonil, Dichlofluanid and Folpet. Every port and marina exhibited high levels of organotin compounds, with concentrations in sediments ranging from 37 ng Sn g−1dry wt in Menton Garavan to over 4000 ng Sn g−1dry wt close to the ship chandler within the port of Villefranche-sur-Mer. TBT degradation indexes suggested that fresh inputs are still made. Among the other antifoulants monitored, only Irgarol 1051 exhibited measurable concentrations in almost every port, with concentrations ranging from 40 ng g−1dry wt (Cannes) to almost 700 ng g−1dry wt (Villefranche-sur-Mer, ship chandler). 相似文献
56.
de Mora S Tolosa I Fowler SW Villeneuve JP Cassi R Cattini C 《Marine pollution bulletin》2010,60(12):2323-2349
The composition and spatial distribution of various petroleum hydrocarbons (PHs), comprising both aliphatic and polycyclic aromatic hydrocarbons (PAHs), and selected chlorinated pesticides and PCBs were measured in biota and coastal sediments from seven countries in the Persian Gulf and the Gulf of Oman (Bahrain, Iran, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates). Evidence of extensive marine contamination with respect to organochlorinated compounds and PHs was not observed. Only one site, namely the BAPCO oil refinery in Bahrain, was considered to be chronically contaminated. Comparison of the results from this survey for Σ DDTs and Σ PCBs in rock oysters from the Gulf of Oman with similar measurements made at the same locations over the past two decades indicates a temporal trend of overall decreasing Σ PCB concentrations in oysters, whereas Σ DDTs levels have little changed during that period. 相似文献
57.
Awad Hassoup Mostafa Toni M. M. F. Shokry A. M. A. Helal Emad K. Mohamed 《Arabian Journal of Geosciences》2016,9(4):313
The 19 October 2012 earthquake (M L = 5.1) occurred in the northern continental margin of Egypt within the Nile Cone at latitude 32.35° N and longitude 31.27° E. The quake was felt over a wide area in north Egypt and East Mediterranean countries, but no casualties have been reported. This area had experienced the large earthquake (Ms = 6.7) of 12 September 1955. The fault plane solution of the 19 October 2012 earthquake is here presented based on the digital seismograms recorded by the Egyptian National Seismological Network (ENSN) and other regional seismic stations. The analysis is carried out using the well-known techniques of first motion polarities of P-wave and the amplitude ratios of P-, SH-, and SV-waves with lower hemisphere projection. The fault plane solution based on the first P-wave onset demonstrates a left lateral strike-slip faulting mechanism, while the solution based on both P-wave polarities and amplitude ratios of P-, SH-, and SV-waves reveals a reverse fault with strike-slip component trending NW–SE to NE–SW, in conformity with the N–S compression along the Hellenic Arc convergence zone. Following the Brune’s model, the source dynamic parameters for the 19 October 2012 earthquake are estimated as corner frequency = 1.47 Hz, fault radius = 0.7 km, stress drop = 22.1 MPa, seismic moment = 2.80E + 16 Nm, and moment magnitude M w = 4.9. These parameters may provide important quantitative information for the seismic hazard assessment studies. 相似文献
58.
Specialisation changes in European regions: the role played by externalities across regions 总被引:1,自引:1,他引:0
This paper seeks to determine the factors underpinning changes in regional specialisation patterns in the European Union between
1991 and 2002. First, we consider a set of determinants previously identified in the regional literature, including agglomeration
effects and other specific regional factors (business cycle, amount of investment, etc.). However, we then also take into
account the fact that the evolution in a region’s specialisation pattern may be affected by the specialisation behaviour of
other regions. Thus, not only do we consider the pattern of evolution in a region’s most proximate neighbours but we also
examine that of their regional peers, i.e., regions with a similar specialisation pattern independent of their location. Notwithstanding,
our empirical evidence indicates that physical distance still plays a very significant, and even more influential, role than
similarity in specialisation. 相似文献
59.
Mabel C. Marulanda Omar D. Cardona Miguel G. Mora Alex H. Barbat 《Natural Hazards》2014,74(3):2071-2088
Understanding and evaluating disaster risk due to natural hazard events such as earthquakes creates powerful incentives for countries to develop planning options and tools to reduce potential damages. The use of models for earthquake risk evaluation allows obtaining outputs such as the loss exceedance curve, the expected annual loss and the probable maximum loss, which are probabilistic metrics useful for risk analyses, for designing strategies for risk reduction and mitigation, for emergency response strategies and for risk financing. This article presents, based on probabilistic risk models, the design and implementation of a risk transfer instrument to cover the private buildings of the city of Manizales, Colombia. This voluntary collective instrument provides financial protection to both, the estate tax payers and the low-income homeowners through a cross-subsidy strategy; besides, it promotes not only the insurance culture but also the solidarity of the community. The city administration and the insurance industry are promoting this program using the mechanism of the property tax payment. This collective insurance helps the government to access key resources for low-income householders recovery and improve disaster risk management at local level. 相似文献
60.