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41.
Combining geographic information system, multicriteria evaluation techniques and fuzzy logic in siting MSW landfills 总被引:2,自引:0,他引:2
Alexandra Gemitzi Vassilios A. Tsihrintzis Evangelos Voudrias Christos Petalas George Stravodimos 《Environmental Geology》2007,51(5):797-811
This study presents a methodology for siting municipal solid waste landfills, coupling geographic information systems (GIS),
fuzzy logic, and multicriteria evaluation techniques. Both exclusionary and non-exclusionary criteria are used. Factors, i.e.,
non-exclusionary criteria, are divided in two distinct groups which do not have the same level of trade off. The first group
comprises factors related to the physical environment, which cannot be expressed in terms of monetary cost and, therefore,
they do not easily trade off. The second group includes those factors related to human activities, i.e., socioeconomic factors,
which can be expressed as financial cost, thus showing a high level of trade off. GIS are used for geographic data acquisition
and processing. The analytical hierarchy process (AHP) is the multicriteria evaluation technique used, enhanced with fuzzy
factor standardization. Besides assigning weights to factors through the AHP, control over the level of risk and trade off
in the siting process is achieved through a second set of weights, i.e., order weights, applied to factors in each factor
group, on a pixel-by-pixel basis, thus taking into account the local site characteristics. The method has been applied to
Evros prefecture (NE Greece), an area of approximately 4,000 km2. The siting methodology results in two intermediate suitability maps, one related to environmental and the other to socioeconomic
criteria. Combination of the two intermediate maps results in the final composite suitability map for landfill siting. 相似文献
42.
Polychlorinated biphenyls (PCBs) are the main constituents of clophen (the liquid of the electric transformers and capacitors)
and have been characterized as potential human carcinogens. PCBs can be a hazardous contaminant of soil and groundwater. We
used the mathematical model variably saturated 2D flow and transport (VS2DT model) to simulate the transport of PCBs from
the soil surface to groundwater for a time period of 30 years. We also used a mathematical model to simulate the colloid-facilitated
PCB transport, under saturated flow conditions. The results showed that PCBs dissolved in water cannot be transported to large
depths in unsaturated soils, because of their strong sorption onto soil and low solubility in water. For soils with very low
or no organic matter content, PCB transport is much faster and the probability of groundwater contamination is much higher.
PCBs can partition to colloids originating from dissolved organic matter in groundwater. Colloid-facilitated PCB transport
is faster compared to PCB transport in aqueous solution with no colloids present. 相似文献
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Yield frequency spectra and seismic design of code‐compatible RC structures: an illustrative example
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The seismic design of an eight‐story reinforced concrete space frame building is undertaken using a yield frequency spectra (YFS) performance‐based approach. YFS offer a visual representation of the entire range of a system's performance in terms of the mean annual frequency (MAF) of exceeding arbitrary global ductility or displacement levels versus the base shear strength. As such, the YFS framework can establish the required base shear and corresponding first‐mode period to satisfy arbitrary performance objectives for any structure that may be approximated by a single‐degree‐of‐freedom system with given yield displacement and capacity curve shape. For the eight‐story case study building, deformation checking is the governing limit state. A conventional code‐based design was performed using seismic intensities tied to the desired MAF for safety checking. Then, the YFS‐based approach was employed to redesign the resulting structure working backwards from the desired MAF of response (rather than intensity) to estimate an appropriate value of seismic intensity for use within a typical engineering design process. For this high‐seismicity and high‐importance midrise building, a stiffer system with higher base shear strength was thus derived. Moreover, performance assessment via incremental dynamic analysis showed that while the code‐design did not meet the required performance objective, the YFS‐based redesign needed only pushover analysis results to offer a near‐optimal design outcome. The rapid convergence of the method in a single design/analysis iteration emphasized its efficiency and practicability as a design aid for practical application. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
45.
The implications of the earthquakes that took place in the central Ionian Islands in 2014 (Cephalonia, M w6.1, M w5.9) and 2015 (Lefkas, M w6.4) are described based on repeat measurements of the local GPS networks in Cephalonia and Ithaca, and the available continuous GPS stations in the broader area. The Lefkas earthquake occurred on a branch of the Cephalonia Transform Fault, affecting Cephalonia with SE displacements gradually decreasing from north (~100 mm) to south (~10 mm). This earthquake revealed a near N–S dislocation boundary separating Paliki Peninsula in western Cephalonia from the rest of the island, as well as another NW–SE trending fault that separates kinematically the northern and southern parts of Paliki. Strain field calculations during the interseismic period (2014–2015) indicate compression between Ithaca and Cephalonia, while extension appears during the following co-seismic period (2015–2016) including the 2015 Lefkas earthquake. Additional tectonically active zones with differential kinematic characteristics were also identified locally. 相似文献
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Ioannis Kastanas Andreas Georgiou Panagiotis Zavros Evangelos Akylas 《Central European Journal of Geosciences》2014,6(1):79-87
This study presents an integrated method for the estimation and analysis of potential wind-energy resources in Cyprus, which is applied at selected sites on the western side of the island. Firstly, a statistical analysis of wind speed and direction data was conducted at six meteorological stations in western Cyprus, establishing daily, monthly and annual variations of wind speed. Also examined were the Weibull distributions of the wind at each site. These wind statistics serve as the basis for estimating corrected statistical distributions over the extended study areas, which were calculated using the Wind Atlas Analysis and Application Program (WAsP) that modifies wind flow estimates based on local topographic effects. As a result, a geographic and wind-resource database was formulated around each station. Aggregation of this data using statistical weighting methods allows the extrapolation of observed results and the visualization for selected hours of the day over the western part of Cyprus. The results indicate the strong influence of the sea-breeze on the island’s wind potential, and identify a number of areas of higher wind-energy potential suitable for wind-resource exploitation. It is hoped that both the methodology applied and results obtained can be further used by potential investors and wind-energy developers. 相似文献
48.
Andreas Nikolaidis Georgios C. Georgiou Diofantos Hadjimitsis Evangelos Akylas 《Central European Journal of Geosciences》2014,6(1):27-41
The Data Interpolating Empirical Orthogonal Functions method is a special technique based on Empirical Orthogonal Functions and developed to reconstruct missing data from satellite images, which is especially useful for filling in missing data from geophysical fields. Successful experiments in the Western Mediterranean encouraged extension of the application eastwards using a similar experimental implementation. The present study summarizes the experimental work done, the implementation of the method and its ability to reconstruct the sea-surface temperature fields over the Eastern Mediterranean basin, and specifically in the Levantine Sea. L3 type Satellite Sea-surface Temperature data has been used and reprocessed in order to recover missing information from cloudy images. Data reconstruction with this method proved to be extremely effective, even when using a relatively small number of time steps, and markedly accelerated the procedure. A detailed comparison with the two oceanographic models proves the accuracy of the method and the validity of the reconstructed fields. 相似文献
49.
Vassiliki Kotroni Evangelos Floros Konstantinos Lagouvardos Goran Pejanovic Luka Ilic Momcilo Zivkovic 《Earth Science Informatics》2010,3(4):209-218
Weather forecasting is based on the use of numerical weather prediction (NWP) models that are able to perform the necessary
calculations that describe/predict the major atmospheric processes. One common problem in weather forecasting derives from
the uncertainty related to the chaotic behaviour of the atmosphere. A solution to that problem is to perform in addition to
“deterministic” forecasts, “stochastic” forecasts that provide an estimate of the prediction skill. A computationally feasible
approach towards this aim is to perform “ensemble forecasts”. Indeed, in the frame of SEE-GRID-SCI EU funded project a Regional
scale Multi-model, Multi-analysis ensemble forecasting system (REFS) was built and ported on the Grid infrastructure. REFS
is based on the use of four limited area models (namely BOLAM, MM5, ETA, and NMM) that are run using a multitude of initial
and boundary conditions over the Mediterranean. This paper presents the tools and procedures followed for developing this
application at a production level. 相似文献
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