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901.
Ardesen is a settlement area which has been significantly damaged by frequent landslides which are caused by severe rainfalls and result in many casualties. In this study a landslide susceptibility map of Ardesen was prepared using the Analytical Hierarchy Process (AHP) with the help of Geographical Information Systems (GIS) and Digital Photogrametry Techniques (DPT). A landslide inventory, lithology–weathering, slope, aspect, land cover, shear strength, distance to the river, stream density and distance to the road thematics data layers were used to create the map. These layer maps are produced using field, laboratory and office studies, and by the use of GIS and DPT. The landslide inventory map is also required to determine the relationship between these maps and landslides using DPT. In the study field in the Hemsindere Formation there are units that have different weathering classes, and this significantly affects the shear strength of the soil. In this study, shear strength values are calculated in great detail with field and laboratory studies and an additional layer is evaluated with the help of the stability studies used to produce the landslide susceptibility map. Finally, an overlay analysis is carried out by evaluating the layers obtained according to their weight, and the landslide susceptibility map is produced. The study area was classified into five classes of relative landslide susceptibility, namely, very low, low, moderate, high, and very high. Based on this analysis, the area and percentage distribution of landslide susceptibility degrees were calculated and it was found that 28% of the region is under the threat of landslides. Furthermore, the landslide susceptibility map and the landslide inventory map were compared to determine whether the models produced are compatible with the real situation resulting in compatibility rate of 84%. The total numbers of dwellings in the study area were determined one by one using aerial photos and it was found that 30% of the houses, with a total occupancy of approximately 2,300 people, have a high or very high risk of being affected by landslides.  相似文献   
902.
The 1:500,000 geological, tectonic and hydrogeological maps of Switzerland have been updated using a new approach for a geographical information system (GIS). Geological, tectonic and hydrogeological data are combined in a single polygon data set. Specific data (point and line elements) are additionally represented on a separate GIS layer for each map respectively. The new 1:500,000 hydrogeological map of Switzerland consists of two different sheets. The first sheet provides information on the near-surface groundwater resources and qualitative estimates of their yield. The second sheet displays the groundwater resource vulnerability and the capacity of lateral contaminant transport. The 1:100,000 hydrogeological map of Switzerland shows the distribution and use of groundwater in a selected area. The near-surface consolidated and unconsolidated rocks are classified in this map according to their permeability and lithological and petrographical properties. The map is available as a pixel map.
Résumé  Les cartes aux 1:500,000 de la Suisse, portant sur la géologie, la tectonique et l’hydrogéologie, ont été mises à jour en utilisant une nouvelle approche pour un système d’information géographique (GIS, en anglais). Les données géologiques, tectoniques et hydrogéologiques ont été combinées sur un seul set de polygones. Les données plus spécifiques (points et lignes) sont représentées dans une couverture séparée, pour chaque carte respectivement. La nouvelle carte hydrogéologique de Suisse au 1:500,000 est constituée de deux différentes feuilles. La première feuille apporte des informations sur les ressources proches de la surface et sur leur rendement. La seconde feuille montre la vulnérabilité des ressources souterraines et le risque de pollution par transport latéral. La carte hydrogéologique de Suisse au 1:100,000 montre la distribution et l’utilisation de l’eau souterraine dans la région sélectionnée. Les roches consolidées ou meubles de sub-surface, sont classées au regard de leur perméabilité et de leurs propriétés lithologique et pétrographique. La carte est disponible pixellisée.

Resumen  Los mapas geológico, tectónico e hidrogeológico de Suiza a escala 1:500,000 han sido actualizados utilizando un nuevo enfoque para un sistema de información geográfico (SIG). Los datos geológicos, tectónicos e hidrogeológicos se combinan en un conjunto de datos en un solo polígono. Por otra parte, para cada uno de los mapas, los datos específicos (elementos puntuales y lineales) se representaron en una capa separa del SIG. El nuevo mapa hidrogeológico de Suiza a escala 1:500,000 contiene dos capas diferentes. La primera de ellas suministra información de los recursos hídricos subterráneos poco profundos y estimaciones cualitativas de sus rendimientos. La segunda capa muestra la vulnerabilidad de este recurso y el riesgo debido al transporte lateral de contaminantes. El mapa hidrogeológico de Suiza a escala 1:100,000 muestra la distribución y uso del agua subterránea en un área seleccionada. Los sedimentos consolidados y no consolidados cercanos a la superficie se clasifican en este mapa en función de su permeabilidad y propiedades litológicas y petrográficas. El mapa se encuentra disponible como un mapa de pixeles.
  相似文献   
903.
阐述了企业在信息化系统建设中,项目负责人如何整合内外部资源的经验和成功做法,怎样找到工作的切入点,以求工作的顺利开展。  相似文献   
904.
This paper explores the disciplining of non-human actors through the example of sustainable drainage systems (SuDS) managing surface water runoff. The lens of performativity is used to examine the move from pre-modern repressive forms of discipline, to mechanisms which attempt a more productive disciplinary engagement by finding space to reform water’s more unruly behaviours. After examining the problems with traditional disciplinary approaches to water of rapid transit and exile, the paper explores the implications of a move towards SuDS technology. This change is examined using a case study of Glasgow, Scotland, where there is an attempt to utilise less repressive disciplinary mechanisms and to find spaces in the city for surface water outside the hard drainage infrastructure. New approaches to the disciplining of urban water are conceptualised as being a performance of tension between water and those who would modify its behaviour.  相似文献   
905.
Geospatial Agents, Agents Everywhere . . .   总被引:1,自引:0,他引:1  
The use of the related terms “agent‐based”, “multi‐agent”, “software agent” and “intelligent agent” have witnessed significant growth in the Geographic Information Science (GIScience) literature in the past decade. These terms usually refer to both artificial life agents that simulate human and animal behavior and software agents that support human‐computer interactions. In this article we first comprehensively review both types of agents. Then we argue that both these categories of agents borrow from Artificial Intelligence (AI) research, requiring them to share the characteristics of and be similar to AI agents. We also argue that geospatial agents form a distinct category of AI agents because they are explicit about geography and geographic data models. Our overall goal is to first capture the diversity of, and then define and categorize GIScience agent research into geospatial agents, thereby capturing the diversity of agent‐oriented architectures and applications that have been developed in the recent past to present a holistic review of geospatial agents.  相似文献   
906.
Advances in sensor techniques, digital acquisition, communication and computing allowed establishment of the field of real-time seismology (Kanamori et al., 1997) and the design of earthquake information systems that provide rapid information on ground motion and potential damage in an area for which a ground motion estimation data base is available and where the inventory of buildings and infrastructure and its vulnerability to shaking is known. We discuss a system for the Romanian capital of Bucharest, where an early warning system with about 30 seconds lead time, shake maps and a sophisticated damage estimation tool for Bucharest have been developed in the frame of the Collaborative Research Center on Strong Earthquakes ().  相似文献   
907.
Numerical models of a sample nuclear power plant (NPP) reactor building, both conventionally constructed and equipped with seismic protective systems, are analysed for both safe shutdown and beyond‐design‐basis earthquake shaking at two coastal sites in the United States. Seismic demands on secondary systems are established for the conventional and seismically isolated NPPs. The reductions in secondary‐system acceleration and deformation demands afforded by the isolation systems are identified. Performance spaces are introduced as an alternate method for evaluating demands on secondary systems. The results show that isolation systems greatly reduce both the median and dispersion of seismic demands on secondary systems in NPPs. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
908.
The aim of this paper is to show a climatology of Mesoscale Convective Systems (MCS) in the NE of the Iberian Peninsula, on the basis of meteorological radar observations. Special attention was paid to those cases that have produced heavy rainfalls during the period 1996–2000. Identification of the MCS was undertaken using two procedures. Firstly, the precipitation structures at the lowest level were recognised by means of a 2D algorithm that distinguishes between convective and non-convective contribution. Secondly, the convective cells were identified using a 3D procedure quite similar to the SCIT (Storm Cell Identification and Tracking) algorithm that looks for the reflectivity cores in each radar volume. Finally, the convective cells (3D) were associated with the 2D structures (convective rainfall areas), in order to characterize the complete MCS. Once this methodology was presented the paper offers a proposal for classifying the precipitation systems, and particularly the MCS. 57 MCS structures were classified: 49% of them were identified as linearly well-organised systems, called TS (39%), LS (18%) and NS (43%). In addition to the classification, the following items were analysed for each MCS found: duration, season, time of day, area affected and direction of movement, and main radar parameters related with convection. The average features of those MCS show an area of about 25000 km2, Zmax values of 47 dBz, an echotop of 12 km, the maximum frequency at 12 UTC and early afternoon and a displacement towards E-NE. The study was completed by analysing the field at surface, the presence of a mesoscale low near the system and the quasi-stationary features of three cases related with heavy rainfalls. Maximum rainfall (more then 200 mm in 6 h) was related with the presence of a cyclone in combination with the production of a convective train effect.  相似文献   
909.
910.
We study protoplanetary disc evolution assuming that angular momentum transport is driven by gravitational instability at large radii, and magnetohydrodynamic (MHD) turbulence in the hot inner regions. At radii of the order of 1 au such discs develop a magnetically layered structure, with accretion occurring in an ionized surface layer overlying quiescent gas that is too cool to sustain MHD turbulence. We show that layered discs are subject to a limit cycle instability, in which accretion on to the protostar occurs in ∼104-yr bursts with ̇ ∼10−5 M yr−1, separated by quiescent intervals lasting ∼105 yr where ̇ ≈10−8 M yr−1. Such bursts could lead to repeated episodes of strong mass outflow in young stellar objects. The transition to this episodic mode of accretion occurs at an early epoch ( t ≪1 Myr), and the model therefore predicts that many young pre-main-sequence stars should have low rates of accretion through the inner disc. At ages of a few Myr, the discs are up to an order of magnitude more massive than the minimum-mass solar nebula, with most of the mass locked up in the quiescent layer of the disc at r ∼1 au. The predicted rate of low-mass planetary migration is reduced at the outer edge of the layered disc, which could lead to an enhanced probability of giant planet formation at radii of 1–3 au.  相似文献   
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