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61.
62.
The Global Earthquake Vulnerability Estimation System (GEVES): an approach for earthquake risk assessment for insurance applications 总被引:4,自引:0,他引:4
Robin Spence Emily So Sarah Jenny Hervé Castella Michael Ewald Edmund Booth 《Bulletin of Earthquake Engineering》2008,6(3):463-483
For the insurance and reinsurance industries, earthquake loss estimation is crucial not only to adequately price its product
but also to manage the accumulation risk in the face of the ever-increasing exposure in highly seismic regions. Changes in
the built environment and a continuously evolving earthquake science make it a necessity for the industry to constantly refine
earthquake loss estimation models. In particular, it has been recognized for a long time that the vulnerability of buildings
to ground shaking is a key parameter in any earthquake risk model. Current methods tend either to rely on the limited historical
damage and loss data or on the numerical simulation of the response of individual buildings to the ground-shaking produced
by earthquakes. Although both methods have their advantages and pitfalls, we are proposing here a simple solution, using transparent
input data, that can be realistically used for the needs of the insurance and reinsurance industry, whether detailed information
about the insured structures is available or not. The resulting product is known as GEVES (Global Earthquake Vulnerability
Estimation System). It is primarily intended for evaluating the mean damage ratio (MDR) suffered by a portfolio of buildings
classified by use, under the action of a given earthquake scenario (i.e. an earthquake of given size at a given distance from
the portfolio of buildings). A key assumption was that macroseismic intensity rather than spectral displacement would be the
basis of loss estimation. The paper describes the model with emphasis on its structure and the justification for the assumptions
made. In addition to a new set of earthquake vulnerability functions, the paper also provides recommendations on some aspects
of the earthquake hazard, in particular about how to define macroseismic intensity at the site of interest, for a given earthquake
scenario. This paper also discusses validation of the GEVES model against calculated vulnerability approaches, and the treatment
of uncertainty within the model. 相似文献
63.
Bernard Bingen Jenny Andersson Ulf Soederlund Charlotte Moeller 《《幕》》2008,31(1):29-34
During the Mesoproterozoic, central Fennoscandia and Laurentia (Greenland) were characterized by a weakly extensional stress regime, as evident from episodic rapakivi granites, dolerite dykes, continental rift intrusives, sandstone basins and continental flood basalts. Along the southwestern active margin of Fennoscandia, the 1.64-1.52 Ga Gothian and 1.52-1.48 Ga Telemarkian accretionary events resulted in oceanwards continental growth. The 1.47-1.42 Ga Hallandian- Danopolonian event included high-grade metamorphism and granite magmatism in southern Fennoscandia. The pre-Sveconorwegian 1.34-1.14 Ga period is characterized by bimodal magmatism associated with sedimentation, possibly reflecting transcurrent tectonics. The Sveconorwegian orogeny involved polyphase imbrication of terranes between 1.14 and 0.97 Ga, as a result of a collision between Baltica and another major plate, followed by relaxation and post-collisional magmatism between 0. 96 and 0. 90 Ga. Recent geologic data support classical models restoring the Sveconorwegian belt directly to the east of the Grenville belt of Laurentia at 1.0 Ga. Fragments of Paleo-to Mesoproterozoic crust showing late Grenvillian-Sveconorwegian (1.00-0.92 Ga) magmatism and/or metamorphism are exposed in several tectonic levels in the Caledonides of Scandinavia, Svalbard and East Greenland, on both sides of the inferred Iapetus suture. Linking these fragments into a coherent late-Grenvillian tectonic model, however, require additional study. 相似文献
64.
The toxicity of a number of new anti-fouling paints, claimed to function by physical means and not by leakage of toxic substances, have been tested on two common organisms in the Baltic Sea, i.e., the red macro alga Ceramium tenuicorne and the copepod Nitocra spinipes. In order to compare the toxicity between the paints a ranking system was developed based on the EC50- and LC50-values. The results showed a wide span in toxicity with the most toxic paints ranked 160 times more toxic than the ones ranked least toxic.
Also, TBT, irgarol and diuron, which have been used as active ingredients in traditional anti-fouling paints, were used to evaluate the sensitivity of the two test organisms. The results showed that the test organisms were equally sensitive to the substances as similar organisms in earlier studies.
In conclusion, the ranking system presented in this study permits ranking and comparison of total toxicity of complex mixtures. 相似文献
65.
Bojan Šavrič Bernhard Jenny 《International journal of geographical information science》2014,28(12):2373-2389
The recently introduced adaptive composite map projection technique changes the projection to the geographic area shown on a map. It is meant as a replacement for the commonly used web Mercator projection, which grossly distorts areas when representing the entire world. The original equal-area version of the adaptive composite map projection technique uses the Lambert azimuthal projection for regional maps and three alternative projections for world maps. Adaptive composite map projections can include a variety of other equal-area projections when the transformation between the Lambert azimuthal and the world projections uses Wagner’s method. To select the most suitable pseudocylindrical projection, the distortion characteristics of a pseudocylindrical projection family are analyzed, and a user study among experts in the area of map projections is carried out. Based on the results of the distortion analysis and the user study, a new pseudocylindrical projection is recommended for extending adaptive composite map projections. The new projection is equal-area throughout the transformation to the Lambert azimuthal projection and has better distortion characteristics then small-scale projections currently included in the adaptive composite map projection technique. 相似文献
66.
Hedman JE Rüdel H Gercken J Bergek S Strand J Quack M Appelberg M Förlin L Tuvikene A Bignert A 《Marine pollution bulletin》2011,62(10):2015-2029
The implementation of the EU Marine Strategy Framework Directive necessitates the development of common criteria and methodological standards for marine environmental monitoring and assessment across Europe. Eelpout (Zoarces viviparus) is proposed as a key indicator organism in the Baltic and North Sea regions. This benthic fish species is widely used in ecotoxicological studies and as a bioindicator of local pollution due to its stationary behavior. Eelpout is included in the environmental monitoring program of several Baltic States, covering both chemical and biological effects measurements, and samples have been archived in environmental specimen banks for >15 years. A method for evaluating the frequency of larval aberrations has been suggested as a standardized assessment tool. The large scientific knowledge-base and considerable experience of long-term chemical and biological effects monitoring and specimen banking, make eelpout a suitable species for the assessment of Good Environmental Status in the Baltic and North Seas. 相似文献
67.
Brooke E. Marston Bernhard Jenny 《International journal of geographical information science》2013,27(7):1144-1165
Relief shading is the most common type of cartographic relief representation for print and digital maps. Manual relief shading results in informative and visually pleasing representations of terrain, but it is time consuming and expensive to produce. Current analytical relief shading can be created quickly, but the resulting maps are not as aesthetically appealing and do not show landscape features in an explicit manner. This article introduces an automated digital method that produces shaded relief with locally adjusted illumination directions to simulate the techniques and cartographic principles of manual relief shading. Ridgelines and valley lines are derived from a digital terrain model, vectorized, and used in a diffusion curve algorithm. A graph analysis generalizes the lines before using them for diffusion curve shading. The direction of illumination is adjusted based on the spatial orientation of ridgelines and valley lines. The diffusion curve shading is combined with standard analytical relief shading to create a final diffusion relief shading image. Similar to manual relief shading, major landforms and the structure of the terrain are more clearly shown in the diffusion relief shading. The presented method best highlights major landforms in terrain characterized by sharp, clearly defined ridges and valleys. 相似文献
68.
Barbara Wohlfarth Francesco Muschitiello Sarah L. Greenwood August Andersson Malin Kylander Rienk H. Smittenberg Margret Steinthorsdottir Jenny Watson Nicola J. Whitehouse 《Boreas: An International Journal of Quaternary Research》2017,46(2):143-161
The Last Termination (19 000–11 000 a BP) with its rapid and distinct climate shifts provides a perfect laboratory to study the nature and regional impact of climate variability. The sedimentary succession from the ancient lake at Hässeldala Port in southern Sweden with its distinct Lateglacial/early Holocene stratigraphy (>14.1–9.5 cal. ka BP) is one of the few chronologically well‐constrained, multi‐proxy sites in Europe that capture a variety of local and regional climatic and environmental signals. Here we present Hässeldala's multi‐proxy records (lithology, geochemistry, pollen, diatoms, chironomids, biomarkers, hydrogen isotopes) in a refined age model and place the observed changes in lake status, catchment vegetation, summer temperatures and hydroclimate in a wider regional context. Reconstructed mean July temperatures increased between c. 14.1 and c. 13.1 cal. ka BP and subsequently declined. This latter cooling coincided with drier hydroclimatic conditions that were probably associated with a freshening of the Nordic Seas and started a few hundred years before the onset of Greenland Stadial 1 (c. 12.9 cal. ka BP). Our proxies suggest a further shift towards colder and drier conditions as late as c. 12.7 cal. ka BP, which was followed by the establishment of a stadial climate regime (c. 12.5–11.8 cal. ka BP). The onset of warmer and wetter conditions preceded the Holocene warming over Greenland by c. 200 years. Hässeldala's proxies thus highlight the complexity of environmental and hydrological responses across abrupt climate transitions in northern Europe. 相似文献
69.
Peter J. Swedlund Jenny G. Webster Gordon M. Miskelly 《Geochimica et cosmochimica acta》2009,73(6):1548-43
Adsorption of Cu2+, Zn2+, Cd2+, and Pb2+ onto goethite is enhanced in the presence of sulfate. This effect, which has also been observed on ferrihydrite, is not predicted by the diffuse layer model (DLM) using adsorption constants derived from single sorbate systems. However, by including ternary surface complexes with the stoichiometry FeOHMSO4, where FeOH is a surface adsorption site and M2+ is a cation, the effect of SO42− on cation adsorption was accurately predicted for the range of cation, goethite and SO42− concentrations studied. While the DLM does not provide direct molecular scale insights into adsorption reactions there are several properties of ternary complexes that are evident from examining trends in their formation constants. There is a linear relationship between ternary complex formation constants and cation adsorption constants, which is consistent with previous spectroscopic evidence indicating ternary complexes involve cation binding to the oxide surface. Comparing the data from this work to previous studies on ferrihydrite suggests that ternary complex formation on ferrihydrite involves complexes with the same or similar structure as those observed on goethite. In addition, it is evident that ternary complex formation constants are larger where there is a stronger metal-ligand interaction. This is also consistent with spectroscopic studies of goethite-M2+-SO42− and phthalate systems showing surface species with metal-ligand bonding. Recommended values of ternary complex formation constants for use in SO4-rich environments, such as acid mine drainage, are presented. 相似文献
70.
Microbial decomposition experiments were used to characterize changes in the amino acid and amino sugar yields and compositions of natural marine substrates during early diagenesis in seawater. On average, 63% of added carbon and 68% of added nitrogen were removed within the first 30 days of decomposition. In all cases, amino acid utilization accounted for a substantial fraction of the removed C and N. Carbon-normalized amino acid yields decreased to less than 50% of their starting values and most of this change occurred within the first 10 days of decomposition. Increases in the concentrations of amino sugars and decreases in the GlcN:GalN ratio in particulate organic matter (POM) illustrated the significance of microbial production during the decomposition of added substrates. Changes in the mol % composition of amino acids during early diagenesis were substantial but highly variable with substrate. Previous survey data collected from the same region were used in conjunction with the experimental data to investigate the utility of several established amino acid-based indices of organic matter diagenesis. This comparison showed that a combination of these degradation indexes is most effective for describing the diagenetic state of dissolved organic matter (DOM). Carbon-normalized amino acid yields were found to be the most effective indicator for early diagenesis. Relative abundances of amino acids were effective indicators of intermediate stages of diagenesis and the mol % composition of the non-protein amino acid γ-Aba (γ-aminobutyric acid) was an effective indicator of advanced DOM diagenesis. 相似文献