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1.
This paper develops a view of vulnerability attempting to capture a constitutive dimension of most disasters, that is their radically surprising moment. Therefore, it builds a conceptual framework, which captures the moment of surprise itself, as well as, its consequences for people by developing a dynamic and actor-oriented understanding of vulnerability. It begins with an outline about how to observe and explain vulnerability by offering a brief overview of how the discussion on vulnerability has evolved over the last 30 years or so. In a second step, the interrelation of knowledge, ignorance and vulnerability is specified. Therefore, a basic understanding of surprises is developed, which is then further distinguished in everyday surprises and ‘radical surprises’. The theoretical argument is substantiated by a case study on a city in Germany, which was severely affected by the 2002 August flood. The paper concludes with some more general implications for the discussion on the interrelation of local knowledge, the dynamics of vulnerability and the occurrence of ‘radical surprises’.  相似文献   

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In this paper, a new methodology is developed for optimization of water and waste load allocation in reservoir–river systems considering the existing uncertainties in reservoir inflow, waste loads and water demands. A stochastic dynamic programming (SDP) model is used to optimize reservoir operation considering the inflow uncertainty, and another model called PSO-SA is developed and linked with the SDP model for optimizing water and waste load allocation in downstream river. In the PSO-SA model, a particle swarm optimization technique with a dynamic penalty function for handling the constraints is used to optimize water and waste load allocation policies. Also, a simulated annealing technique is utilized for determining the upper and lower bounds of constraints and objective function considering the existing uncertainties. As the proposed water and waste load allocation model has a considerable run-time, some powerful soft computing techniques, namely, Regression tree Induction (named M5P), fuzzy K-nearest neighbor, Bayesian network, support vector regression and an adaptive neuro-fuzzy inference system, are trained and validated using the results of the proposed methodology to develop real-time water and waste load allocation rules. To examine the efficiency and applicability of the methodology, it is applied to the Dez reservoir–river system in the south-western part of Iran.  相似文献   

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In this work, a talc and vermiculite mine from the province of Córdoba (Argentina) was investigated with special emphasis on the occurrence of asbestiform and non-asbestiform phases. The meta-ultramafic rock was studied by a multimethodological approach, complementing field studies with petrographic-mineralogical, compositional and morphological analyses. Samples were examined by stereomicroscopy, polarizing light microscopy, SEM–EDS, XRD, DSC-TGA and FTIR. Complementary, compositional and textural analyses were performed with FE-SEM–EDS and EPMA. Talc-rich veins with a laminar and fibrous appearance were at first recognized. However, the fibrous morphology observed both in the field and by microscopy is due to an apparent habit because of the sample orientation. To avoid erroneous interpretations, studies by secondary electron images (SEM) are fundamental to carrying out this type of analysis. Tremolite was identified in different zones of the outcrop; however, only ~40% of the crystals located in the vermiculite zone have dimensions to be considered as asbestiform fibres in the range of respirable particles. In these types of complex deposits affected by superimposed metamorphic, igneous and deformational events, multimethodological approaches are necessary to develop models of occurrence of asbestiform morphologies that may be applicable to other with similar characteristics.  相似文献   

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The alluvial aquifer of the Alto Guadalquivir River is one of the most important shallow aquifers in Jaén, Spain. It is located in the central-eastern part of the province, and its groundwater resources are used mainly for crop irrigation in an agriculture-dominated area. Hydrochemical and water-quality data obtained through a 2-year sampling (2004–2006) and analysis program indicate that nitrate pollution is a serious problem affecting groundwater due to the use of nitrogen (N)-fertilizers in agriculture. During the study, 231 water samples were collected from wells and springs to determine water chemistry and the extent of nitrate pollution. The concentration of nitrate in groundwater ranged from 1.25 to 320.88 mg/l. Considerable seasonal fluctuations in groundwater quality were observed as a consequence of agricultural practices and other factors such as annual rainfall distribution and the Guadalquivir River flow regime. The chemical composition of the water is not only influenced by agricultural practices, but also by interaction with the alluvial sediments. The dissolution of evaporites accounts for part of the Na+, K+, Cl, SO4 2−, Mg2+, and Ca2+, but other processes, such as calcite precipitation and dedolomitization, also contribute to groundwater chemistry.  相似文献   

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With 60% of the world’s population living within the coastal zone, coastal erosion is considered as a global problem. The coasts of the Maltese Islands hold a variety of formations resulting from coastal erosion. Beach nourishment is one of the protective measures taken against coastal erosion. This paper focuses on two of the nourished beaches within the Maltese Islands, St George’s Bay (St Julians) and Pretty Bay (Birżebbuġa), that have undergone extensive sand augmentation during the past decades and looks at the extent of how coastal erosion and beach replenishment may have influenced public perception. Through a triangulation of interviews, it seeks to understand the views of beach users, researchers, representatives, and beach managers. It presents divergences in interviewee opinions and ideas on St George’s Bay and Pretty Bay and illustrates that public perception tends to reflect the type of urban area surrounding each replenished beach. Recommendations and suggestions are also presented to promote awareness towards coastal processes and their impacts.

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8.
Chen  Tzu-Ling  Paris  Larry 《Natural Hazards》2022,111(3):2627-2647
Natural Hazards - Major earthquakes in a given location are unpredictable, infrequent, and often fatal. Using data from a previous earthquake disaster, this study explores the relationship between...  相似文献   

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The geomorphology of the Lar Valley in the Northeast of Tehran, the Capital of Iran, is under the geological influence of the Central Alborz, in which the different geological formations are folded and thrust, time and again over each other by faults, creating the heights. The Damavand volcano is located to the east of Lar Valley, appearing in the heights of Alborz at the point of deviation in the structural strike of Alborz chain and along the faults during the quaternary period. The physiographic, landslide phenomenon, rock fall, valleys, water courses and alluvial fans in the Lar Valley were reviewed and studied according to aerial photographs, satellite images and field observations from the aspect of their susceptibility to the impact of faults. The results indicate that 80% of the peaks and high mountains in Lar Valley are created and influenced by the action of overthrust faults. Ninety percent of the land and rock sinking are located in the intermediate regions between the faults, and they are believed to be the results of fault impacts. Seven out of the nine cases of landslide in Lar are located on or in the margin of the faults depicting the latter’s influence. The floor ratios of eight valleys were calculated and it was determined that in addition to the impacts of faults on creating the valleys, the situation of most of these along the margins of the faults as well as seven valleys are influenced by faults. The slope of rivulets and auxiliary rivers and their angles in relation to each other and the main river were calculated. The results showed that seven rivulets were under the influence of faults. Fifty-nine percent of the alluvial fans in Lar Valley were greatly influenced by faults, whereas 49% were under their normal impact. The supposition in this study is that the results can be used to identify faults and their characteristics.  相似文献   

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The contemporary technological advancements of the twenty-first century are introducing paradigm shifts in every aspect of life. The “Smart City” concept has also brought the latest emerging technologies and their applications to the urban areas. The integration of Nano-technological devices collecting and transmitting data coupled with the availability and penetration of high-speed internet will only raise this potential by providing an easy way to receive and send real-time data more swiftly. The devices could also be connected with each other via the internet under the Internet of Things (IoT), making it possible to establish the machine to machine (M2M) communication between them. This large amount of urban Big Data can also deploy machine learning assisted techniques to ensure robust and precise urban analysis for getting significant insights and desired simulations ensuring the proper deployment as well as utilization of the phenomenon of Urban Intelligence. As the cities are entitled to become “Smart” in due course of time, these Information and Communication Technologies (ICTs) will play a major role in improving the efficiency and effectiveness of urban services and management. Due to their highly versatile and adaptable nature, these technologies can be linked with different components of Smart City thereby enhancing the efficiency and capability of the existing urban systems. This paper discusses the emerging concept of the Internet of Things (IoT) and other associated technologies within the context of contemporary urban scenarios through relevant case studies. It further presents crucial insights based on the influence of these technologies as well as their associated challenges while also exploring the implications of the concepts like ‘Super City’ on the cities of tomorrow.

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12.
Miao  Cheng  Ding  Mingtao 《Natural Hazards》2017,85(2):1135-1150
Natural Hazards - After the 2008 Wenchuan earthquake, secondary geological disasters occurred frequently and caused huge economic losses in the upper reaches of Min River. In this paper,...  相似文献   

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Eucrites are basaltic meteorites that cooled rapidly but are in many instances thermally metamorphosed and impact brecciated. The exact timing of these events remains unclear. In this study, Ni isotopic compositions and Fe/Ni elemental ratios are presented for two non-cumulate eucrites, Bouvante and Juvinas, including mineral separates from the latter. The samples are characterized by variable, well-resolved 60Ni-excesses consistent with the former presence of live 60Fe (t1/2 = 2.62 Ma) at the time of eucrite crystallization. A significant fraction of Ni with a terrestrial-like composition appears to be surface correlated. This Ni may be the product of terrestrial contamination or was introduced by a chondritic impactor during brecciation. Altogether, the data provide evidence for a complex and probably multi-stage history of Fe and/or Ni redistribution, which impedes the interpretation of the chronological data.  相似文献   

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International Journal of Earth Sciences - The Southern Brasília Orogen is a Neoproterozoic belt that occurs along the southernmost border of the São Francisco Craton where the...  相似文献   

15.
The crustal section beneath amphibolite Nied?wied? Massif (Fore-Sudetic Block in NE Bohemian Massif), modelled on the basis of geological and seismic data, is dominated by gneisses with subordinate granites (upper and middle crust) and melagabbros (lower crust). The geotherm was calculated based on the chemical analyses of the heat-producing elements in the rocks forming the crust and the measurements of their density and heat conductivity. The results were verified by heat flow calculations based on temperature measurements from 1,600?m deep well in the Nied?wied? Massif and by temperature–depth estimates in mantle xenoliths coming from the nearby ca. 4.5?My basanite plug in Lutynia. The paleoclimate-corrected heat flow in the Nied?wied? Massif is 69.5?mW?m?2, and the mantle heat flow is 28?mW?m?2. The mantle beneath the Massif was located marginally relative to the areas of intense Cenozoic thermal rejuvenation connected with alkaline volcanism. This results in geotherm which is representative for lithosphere parts located at the margins of zones of continental alkaline volcanism and at its waning stages. The lithosphere–asthenosphere boundary (LAB) beneath Nied?wied? is located between 90 and 100?km depth and supposedly the rheological change at LAB is not related to the appearance of melt.  相似文献   

16.
 RedSanders in their natural distribution occur almost exclusively in quartzites and shales. This indicates the geobotanical response to these rock types in the semi-arid tract of the southeastern portion of Andhra Pradesh in the tropical dry deciduous forests of Chittoor, Cuddapah and Nellore districts. Thus Red Sanders are important from a commercial point of view and also a useful tool to demarcate stratigraphic formations. Received: 27 April 1998 · Accepted: 21 July 1998  相似文献   

17.
This paper explores the links between a strategic policy, urban consolidation, and house prices by examining the changes in the mix of housing and in house price for the period 1991–2004. We contend that urban consolidation could be seen as a source of additional supply, (which might be expected to be felt in lower prices and so contribute to a local policy objective) but also as a stimulus to demand (by developers who could bid up the price of lots where it was understood more housing could be built). Analyses were carried out at the metropolitan and sub-regional scales using correlation tests. The research finds very weak statistical connections, and concludes that this policy has not been associated with price changes.  相似文献   

18.
Geological mapping of an unexposed area can be supported by indirect methods. Among these, the use of mushrooms as geobotanical indicators and the shallow-penetration electromagnetic VLF method proved to be useful in the Bükk Mountains. Mushrooms have not been applied to geological mapping before. Common species like Boletus edulis and Leccinum aurantiacum are correlated with siliciclastic and magmatic formations while Calocybe gambosa is correlated with limestone. The validity of this correlation observed in the eastern part of the Bükk Mts. was controlled on a site where there was an indicated (by the mushrooms only) but unexposed occurrence of siliciclastic rocks not mapped before. The extent and structure of this occurrence were explored with the VLF survey and a trial-and-error method was applied for the interpretation. This case study presented here demonstrates the effectiveness of the combination of these relatively simple and inexpensive methods.  相似文献   

19.
Noto is an important Baroque urban center in south-eastern Sicily, which was completely reconstructed after the severe earthquake of 1693. Most of its monuments and historic buildings were built in Pietra di Noto stone, a pale cream calcarenite, quarried in outcrops located near the city. This stone, still currently used as building material, is undergoing many forms of alteration and degradation, which cause significant damage to monuments. In this study, three commercial protective products were tested on some Noto calcarenite samples from quarries, with the aim of assessing their protective effectiveness. In particular, petrographic analyses by optical microscopy were carried out for textural characterization of the stone materials. Capillary water absorption, porosimetric and colorimetric procedures, UV radiation and salt crystallization aging tests were performed to better evaluate interactions between protective products and substrate.  相似文献   

20.
Severe stone deterioration is evident at the Cologne cathedral. In particular, the “Drachenfels” trachyte, which was the building material of the medieval construction period, shows significant structural deterioration as well as massive formation of gypsum crusts. The present article investigates crust formation on limestone, sandstone, and volcanic rock from the Cologne cathedral as well as from the Xanten and Altenberg cathedrals. These three buildings, showing varying degrees of deterioration, are located in different areas and exposed to varying industrial, urban, and rural pollution. Thin laminar and black framboidal crusts form on calcareous as well as silicate stone. The lack of a significant intrinsic calcium and sulfur source for the formation of the gypsum crusts on the Drachenfels trachyte indicates major extrinsic environmental impact: a sufficient offer of SO x from pollutant fluxes as well as external calcium sources (e.g., pollution, mortars, neighboring calcite stones). Chemical analyses reveal strong gypsum enrichment within the crusts as well as higher concentrations of lead and other pollutants (arsenic, antimony, bismuth, tin, etc.), which generally can be linked to traffic and industry. The formation of weathering crusts in an industrial environment is clearly distinguishable from that in rural areas. Scanning electron microscopy observations confirm that the total amount of pollution is less at the Altenberg cathedral than at the Cologne and Xanten cathedrals. XRF analyses show that the formation of gypsum occurs in lower amounts at Altenberg. This correlates well with the measured SO2 content and the intensity of the decay at the different locations. Furthermore, the different types of crusts, e.g., framboidal and laminar, can be differentiated and assigned to the different locations. The black weathering crusts on the silicate Drachenfels trachyte contribute to the degradation of the historic building material. They enhance mechanical moisture-related deterioration processes and the decay by chemical corrosion of rock-forming minerals. Although SO2 concentrations in air have shown a strong decrease over the past 30 years, degradation in connection with weathering crusts is still observed. This indicates that not only contemporary or recent emissions, but also past pollutant concentrations have to be considered.  相似文献   

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