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The creation of earthquake hazard maps requires various datasets with selected attenuation relations. Based on the selected attenuation relation, the calculation time varies from half an hour to a couple of days. The length of time needed to create an earthquake hazard map also depends on the resolution of the resulting map. The time gets longer as the resolution of the resulting earthquake hazard map gets higher. The basic form of an attenuation relation requires complex calculation algorithms including geospatial information related to the region of interest. Nowadays, next-generation attenuation (NGA) models are introduced to generate more realistic earthquake hazard maps. However, the more complex the attenuation relation is, the longer time will be required to create a hazard map. This paper offers a new method to create high-resolution earthquake hazard maps, faster than using traditional attenuation relation methods, by using an analytic hierarchy process of spatial multi-criteria decision analysis and geographic information systems. This method has been generated and tested for the city of Istanbul. The resulting maps are compared with the earthquake hazard maps created for the city of Istanbul by using the NGA model of Boore and Atkinson (in Boore–Atkinson NGA ground motion relations for the geometric mean horizontal component of peak and spectral ground motion parameters (trans: Engineering Co, University of California B). Pacific Earthquake Engineering Research Center 2007). A second output of this paper is a map of the elements at risk (EaR) for the population and buildings of Istanbul, and the introduction of a new approach of net elements at risk (NEaR). 相似文献
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AbstractExtracting built-up areas from remote sensing data like Landsat 8 satellite is a challenge. We have investigated it by proposing a new index referred as built-up land features extraction index (BLFEI). The BLFEI index takes advantage of its simplicity and good separability between the four major component of urban system, namely built-up, barren, vegetation and water. The histogram overlap method and the spectral discrimination index (SDI) are used to study separability. BLFEI index uses the two bands of infrared shortwaves, the red and green bands of the visible spectrum. OLI imagery of Algiers, Algeria, was used to extract built-up areas through BLFEI and some new previously developed built-up indices used for comparison. The water areas are masked out leading to Otsu’s thresholding algorithm to automatically find the optimal value for extracting built-up land from waterless regions. BLFEI, the new index improved the separability by 25% and the accuracy by 5%. 相似文献
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The aim of this article is to investigate the dynamical behaviour ofmultiphase atmospheric chemical mechanisms. Reducing procedures areapplied to a multiphase chemical box model including gas-phasereactions, aqueous-phase reactions and interfacial mass transfer. The lumping of species is computed in an automatic wayusing an efficient algorithm (apla). The computed lumped species arerelated to the fast behaviour of chemical and microphysical processessuch as Chapman cycle, ionic dissociations within the cloud drops andinterfacial Henry's equilibria. Depending on some parameters (liquidwater content, droplet radius) mixed lumped species (including both phases) may also becomputed. We show the existence of hierarchical reduced models due to the existence ofmultiple timescales. We use a special algorithm (dan2) in order tosolve the reduced models. Such models are accurate and the relative errorremains under the threshold of 1%. The speed-up is up to a factor 5comparedwith a fully implicit method (Gear) for the same accuracy. The key pointis that it provides a good qualitative understanding for the behaviourof the kinetic scheme. 相似文献
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In the well-log data processing, the principal advantage of the nuclear magnetic resonance (NMR) method is the measurement of fluid volume and pore size distribution without resorting to parameters such as rock resistivity. Preliminary processing of the well-log data allowed first to have the petrophysical parameters and then to evaluate the performances of the transverse relaxation time T 2 NMR. Petrophysical parameters such as the porosity of the formation as well as the effective permeability can be estimated without having recourse the fluid type. The well-log data of five wells were completed during the construction of intelligent models in the Saharan oil field Oued Mya Basin in order to assess the reliability of the developed models. Data processing of NMR combined with conventional well data was performed by artificial intelligence. First, the support vector regression method was applied to a sandy clay reservoir with a model based on the prediction of porosity and permeability. NMR parameters estimated using intelligent systems, i.e., fuzzy logic (FL) model, back propagation neural network (BP-NN), and support vector machine, with conventional well-log data are combined with those of NMR, resulting in a good estimation of porosity and permeability. The results obtained during the processing are then compared to the FL and NN regression models performed by the regression method during the validation stage. They show that the correlation coefficients R 2 estimated vary between 0.959 and 0.964, corresponding to the root mean square error values of 0.20 and 0.15. 相似文献
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A coal mine panel claimed to infringe on a permit boundary, or to create an hazard after subsidence has been the subject of lawsuits. We study at the Soma–Darkale coalfield (Manisa, Turkey), the footprint of a lignite coal mine panel at a depth of about 150–200 m by mapping all of the surface fractures we could observe, and by developing a post-subsidence density model that we verified through gravity measurements with positive Bouguer anomaly. With the analysis of the fracture map and the gravity data, we were able to identify the footprint of a mine panel from the effect of the anomalous mass due to denser overburden material filling up the space after the extraction of less-dense lignite. Whereas, using empirical methods like the so-called “limit line approach” to evaluate the extent of the area where mining can have subsidence-induced surface fracturing, one could not recognize for certain infringement of permit boundaries. The orientations of the fractures we mapped at the ground surface, the Bouguer gravity map, and a test borehole indicated the presence and dimensions of a coal panel in dispute. The presented approach based on gravity method and fracture observations may be an example to help settle conflicts related to the position of the longwall mine panel. 相似文献
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Resisting urban renewal in Istanbul 总被引：1，自引：1，他引：0
Ozan Karaman 《Urban geography》2013,34(2):290-310
In this article I examine grassroots responses to state-directed urban renewal in two poor neighborhoods in Istanbul. Through detailed analysis of resident perspectives and urban association tactics, I explore various factors that shape the trajectories of resistance to urban renewal, including solidarity networks, levels of participation and trust in local neighborhood associations, strength of neighborhood identity, extra-local support, and the traditions and channels of negotiation with state actors. I argue that these factors are articulated by a distinct “politics of compensation”—a term that I borrow from Ananya Roy—that is particular to the contemporary neoliberal condition. I find that grassroots mobilizations in Istanbul do not necessarily operate in opposition to neoliberalism; in fact, many struggles remain within the conceptual space of neoliberalism and its cost-benefit calculations. These findings contribute to the emerging literature on struggles against urban renewal in the global south. 相似文献
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