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In this article, the mechanical behavior of a Jiangsu marine clay was investigated by drained triaxial tests, traixial rheological tests, and one-dimensional compression and swelling tests. A visco-plastic model, the Bingham model combining two yield surfaces model, was proposed to describe the time-dependent deformation behaviors of the marine clay. The governing equation of Biot's consolidation theory for the visco-plastic soil is solved using a finite element code which incorporates the visco-plastic model. Using the finite element method, settlements of a typical embankment on the Lianxu expressway in China are calculated. Settlement calculations using the visco-plastic model are in agreement with the measured settlements in the field. The results demonstrate that the visco-plastic model is appropriate for calculating the visco-plastic deformations of Jiangsu marine clay. Theoretical and experimental studies show that the visco-plastic deformation of Jiangsu marine clay is substantial.  相似文献   
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ABSTRACT

In 2013, the International Association of Hydrological Sciences (IAHS) launched the hydrological decade 2013–2022 with the theme “Panta Rhei: Change in Hydrology and Society”. The decade recognizes the urgency of hydrological research to understand and predict the interactions of society and water, to support sustainable water resource use under changing climatic and environmental conditions. This paper reports on the first Panta Rhei biennium 2013–2015, providing a comprehensive resource that describes the scope and direction of Panta Rhei. We bring together the knowledge of all the Panta Rhei working groups, to summarize the most pressing research questions and how the hydrological community is progressing towards those goals. We draw out interconnections between different strands of research, and reflect on the need to take a global view on hydrology in the current era of human impacts and environmental change. Finally, we look back to the six driving science questions identified at the outset of Panta Rhei, to quantify progress towards those aims.
Editor D. Koutsoyiannis; Associate editor not assigned  相似文献   
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Abstract

The estimation of flood damage is an important component for risk-oriented flood design, risk mapping, financial appraisals and comparative risk analyses. However, research on flood-loss modelling, especially in the commercial sector, has not gained much attention so far. Therefore, extensive data about flood losses were collected for affected companies via telephone surveys after the floods of 2002, 2005 and 2006 in Germany. Potential loss determining factors were analysed. The new Flood Loss Estimation MOdel for the commercial sector (FLEMOcs) was developed on the basis of 642 loss cases. Losses are estimated depending on water depth, sector and company size as well as precaution and contamination. The model can be applied to the micro-scale, i.e. to single production sites as well as to the meso-scale, i.e. land-use units, thus enabling its countrywide application.

Citation Kreibich, H., Seifert, I., Merz, B. & Thieken, A. H. (2010) Development of FLEMOcs – a new model for the estimation of flood losses in the commercial sector. Hydrol. Sci. J. 55(8), 1302–1314.  相似文献   
25.
Abstract

The estimation of flood loss is difficult, especially in the commercial sector, because of its great inhomogeneity. However, the reliability of loss modelling is fairly unknown, since flood-loss models are scarcely validated. The newly developed Flood Loss Estimation MOdel for the commercial sector (FLEMOcs) was validated on the micro-scale using a leave-one-out cross-validation procedure. Additionally, different meso-scale loss functions were compared. Meso-scale model application was undertaken in 19 municipalities which were affected during the 2002 flood in Germany. Model results were compared with the results of three other loss models, as well as with official loss records. The micro-scale validation shows very good results, with no bias and mean absolute errors between 23 and 31%. The meso-scale validation indicates that FLEMOcs provides good results, especially in large areas with many affected companies where high losses are expected.

Citation Seifert, I., Kreibich, H., Merz, B. & Thieken, A. H. (2010) Application and validation of FLEMOcs – a flood-loss estimation model for the commercial sector. Hydrol. Sci. J. 55(8), 1315–1324.  相似文献   
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The inner shelves of active, energetic continental margins are frequently defined as regions of sediment segregation and fine-sediment bypassing. The Waiapu River, North Island, New Zealand presents an opportunity to study fine-sediment segregation and strata formation in a spatially constrained, highly energetic, aggradational setting, with one of the highest sediment yields on earth. We present evidence that the inner shelf of the Waiapu River plays a significant role in both the fate of fine-grained (<63 μm) riverine sediments and the formation of continental margin stratigraphy. Results obtained from high-resolution interferometric bathymetry and high-frequency seismic mapping ground-truthed by cores show significant stratigraphic spatial variation preserved on the Waiapu inner shelf. This spatial variation is likely controlled by spatially-distinct sediment deposition and resuspension processes as well as antecedent geology. Two distinct depositional regions are interpreted as: (1) surface plume-dominated with partial resuspension, characterized by acoustically transparent seismic reflection profiles and muddy sands; and (2) event-layer dominated, characterized by thickly laminated sediments. A modern-day bathymetric low overlying an observed paleochannel may influence the fate of hyperpycnal flows transiting the shelf via bathymetric steering. Fining-upward sequences found over the entire shelf are interpreted to represent deforestation-induced sedimentation that has overwhelmed the ability of the energetic system to resuspend and segregate fine sediments. We conclude that the primary control on strata formation on the inner shelf of the Waiapu River is local sediment supply.  相似文献   
27.
The study objective was to analyse how capitalized and non-capitalized resource rents act as mechanisms of innovation in nature-based tourism within a centre–periphery context dominated by distance, instability, and dependency. The authors studied 55 out of 64 businesses engaged in tourism in Nordkapp Municipality in Norway in the period 2002–2012. Data were collected from a survey, interviews, and empirical observations, and then analysed using both deductive and inductive methodological approaches. The main findings were that tourism in the Nordkapp Municipality had suffered from a lack of local innovation initiatives caused by the capitalized resource rent of tourism to North Cape and its leakage. Nevertheless, local tourism had increased partly because of the inclusion of new and more attractive products, due to the open-access, non-capitalized resource management in fishing tourism that operated simultaneously with the closed and capitalized context of North Cape tourism. The authors conclude that this open-access regime of fishing tourism stimulated innovation and further development of coastal tourism, and even affected traditional North Cape tourism. Non-capitalized resource rent had not leaked out because it had not been collected by external companies and because it had acted as an innovation mechanism on the periphery.  相似文献   
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Successful species conservation typically results in conflicts between wildlife protection and economic uses of natural resources as in fisheries and aquaculture. This article shows why managing these conflicts require a more comprehensive approach than currently pursued by endangered species conservation programmes. Against the background of several case studies focussing on wildlife conflicts in European waters this article derives two challenges for institutional response: First, the question of mandate—which societal actor initiates management related processes that require multiple actors to collaborate? Second, how can continuous processes of collaboration be sustained?  相似文献   
30.
Conservation Development (CD) is a land-use tool to reduce the impacts of development on natural resources, yetthe use of CD is highly variable. We used a collaborative conservation model to examine factors influencing adoption and implementation to improve the future application of CD. We interviewed 2–3 individuals including planners, board members, and developers (n?=?46) from 16 rural communities in the intermountain west and northeast U.S. Motivations to preserve rural character or comply with state statutes drove adoption. Greater capacity such as outside expertise, model regulations, and iterative revisions of ordinances was associated with stronger ordinances. Adoption processes including ample dialog across diverse constituents, especially those overseeing subdivision development, facilitated higher rates of implementation. Concerns over open space management, lack of successful CD examples, and inexperience with CD posed barriers to implementation. Understanding social context revealed the strengths and shortcomings of CD and provided guidance for strategically engaging communities in private lands conservation.  相似文献   
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