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91.
This paper presents a spatial decision support tool that implements the Ordered Weighted Averaging (OWA) method. OWA is a
family of multicriteria evaluation operators characterised by two sets of weights: criterion importance weights and order
weights. We propose a highly interactive way of choosing, modifying, and fine-tuning the decision strategy defined by the
order weights. This exploratory approach to OWA is supported by a graphical representation of the operator's behaviour in
terms of decision risk and tradeoff/dispersion between criteria. Our prototype implementation is based on the CommonGIS software,
and thus, Web-enabled and working with vector data. We successfully demonstrate online, exploratory support of spatial decision
strategies using a data set of skiing resorts in Wallis, Switzerland.
Received: 24 September 2002 / Accepted: 10 January 2003 相似文献
92.
Jacek W Kaminski David A Plummer Lori Neary John C McConnell Joanna Struzewska Lech Lobocki 《Physics and Chemistry of the Earth》2002,27(35):1517-1524
A three-dimensional air quality model (MC2-AQ) developed for studying oxidant chemistry on regional to urban scales over North America was adapted and implemented for European conditions. The modelling system is based on the Canadian Mesoscale Compressible Community (MC2) Model, a non-hydrostatic meteorological model, to which modules permitting on-line calculations of chemical transformations, anthropogenic and biogenic emissions, and deposition were added. The transport of chemical species is done on the same grid and with the same advection, convection, and diffusion schemes as are used for the meteorological fields. The developed model is highly flexible and was adapted to different scales by allowing for self-nesting. In this paper we present model results for a high-ozone episode, June 18–26, 2000, over Europe. The modelling system was able to reproduce general characteristics (growth, extent, and dissipation) of the pollution episode. Accumulation of ozone precursors during weak wind and high-temperature synoptic conditions was essential for episode formation. Subsequent episode development and advancement across Europe was driven by frontal systems. A stationary front associated with a low-pressure system over Ukraine prevented the further eastward transport of the polluted air mass. The episode was terminated after the passage of a cold front advecting relatively clean Atlantic air mass. 相似文献
93.
Virginia Souza‐Egipsy Jacek Wierzchos Carlos Sancho Anchel Belmonte Carmen Ascaso 《地球表面变化过程与地形》2004,29(13):1651-1661
Sandstone structural landscapes in the semi‐arid Torrollones de Gabarda area (Province of Huesca, NE Spain) are often covered by a well developed biological soil crust of lichens, mosses and cyanobacteria and black coatings on vertical surfaces. By using scanning electron microscopy with backscattered detector imaging, the biological soil crust studied evidenced high activity in the sandstone–crust interface. Processes such as physical disintegration, etching and dwelling as well as biomineralization by calcium oxalate and ?xation of mineral particles by extracellular polymeric substances were observed. On the horizontal sandstone surfaces these processes may cause the occurrence of gnammas and the development of a protective coating that favours intense ?aking when the crust is disturbed. On the sandstone cliffs, columnar and tafoni weathering development is clearly guided by the protective action of the biological soil crust. These qualitative observations are important to develop methodologies to address their quantitative importance in geomorphological processes in semi‐arid landscapes. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
94.
95.
Żaneta Polkowska Kamila Skarżyńska Tadeusz Górecki Jacek Namieśnik 《Journal of Atmospheric Chemistry》2006,53(3):211-236
Formaldehyde levels were determined in various forms of atmospheric precipitation (rain, snow, road and roof runoff, throughfall) and deposition (rime, hoarfrost, dew) collected over twelve months at various locations in two large urban agglomerations and along two highways. HCHO was found in 303 of 500 samples analyzed, with concentrations ranging from 0.05 to 10.7 mg/dm3. The results confirmed the significant effect of vehicular traffic on formaldehyde levels in various forms of wet deposition. Correlations of formaldehyde levels with other parameters commonly monitored in precipitation and/or deposition were also examined. No correlation was found between HCHO levels and rain volume. On the other hand, positive correlations were found for hydrogen peroxide, non-sea-salt sulphate, nitrate, ammonia, and total organic carbon (TOC). In addition, the effect of selected meteorological parameters (temperature, wind speed, wind direction, rainfall) on the concentration of formaldehyde in various forms of precipitation and runoff (road runoff, roof runoff, throughfall) was studied. The only correlation found was that between HCHO concentration and daily rainfall. 相似文献
96.
A series of analogue models are used to demonstrate how the multistage development of the Mid‐Polish Trough (MPT) could have been influenced by oblique basement strike–slip faults. Based on reinterpretation of palaeothickness, facies maps and published syntheses of the basin development, the following successive stages in the Mesozoic history of the south eastern part of the MPT were simulated in the models: (1) Oblique extension of the NW segment of the MPT connected with sinistral movement along the Holy Cross Fault (HCF, Early Triassic–latest Early Jurassic). (2) Oblique extension of both NW and SE segment of the MPT, parallel to the HCF (latest Early and Middle Jurassic). (3) Oblique extension of the SE segment of the MPT and much lesser extension of its NW segment connected with dextral movement along the HCF (Early Oxfordian–latest Early Kimmeridgian). (4) Oblique extension of the SE segment of the MPT and much lesser extension of its NW segment connected with dextral movement along the Zawiercie Fault (ZF, latest Early Kimmeridgian–Early Albian). (5) Oblique inversion of the NW segment of the MPT connected with dextral movement along the HCF (Early Albian–latest Cretaceous). (6) Oblique inversion of the SE segment of the MPT along the W–E direction (latest Cretaceous–Palaeogene). The different sense of movements of these two basement strike–slip faults (HCF and ZF) resulted in distinct segmentation of the basin and its SW margin by successive systems of extensional en‐echelon faults. The overall structure of this margin is controlled by the interference of the border normal faults with the en‐echelon fault systems related to successive stages of movement along the oblique strike–slip faults. This type of en‐echelon fault system is absent in the opposite NE‐margin of the basin, which was not affected by oblique strike–slip faults. The NE‐margin of the basin is outlined by a typical, steep and distinctly marked rift margin fault zone, dominated by normal and dip–slip/strike–slip faults parallel to its axis. Within the more extended segment of the basin, extensive intra‐rift faults and relay ramps develop, which produce topographic highs running across the basin. The change in the extension direction to less oblique relative to the basin axis resulted in restructuring of the fault systems. This change caused shifting of the basin depocentre to this margin. Diachronous inversion of the different segments of the basin in connection with movement along one of the oblique basement strike–slip faults resulted in formation of a pull‐apart sub‐basin in the uninverted SE‐segment of the basin. The results of the analogue models presented here inspire an overall kinematic model for the southeastern segment of the MPT as they provide a good explanation of the observed structures and the changes in the facies and palaeothickness patterns. 相似文献
97.
International Journal of Earth Sciences - Heat flow high −80 ± 10 mW/m2 in the northern western parts of the Western Canadian foreland basin is in large... 相似文献
98.
Monitoring of organic pollutants in coastal waters of the Gulf of Gdańsk, Southern Baltic 总被引:1,自引:0,他引:1
This paper presents an overview of changes in organic pollution of coastal waters of the Gulf of Gdańsk (Baltic Sea). Toxic pollutants including volatile organic compounds (VOC), volatile organohalogen compounds (VOX), chlorophenols, phenoxyacids, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were determined in seawater from the Gulf of Gdańsk coastal waters in the period 1996-2001. In the case of the Gulf of Gdańsk, non-conservative behaviour of VOC was observed due to random temporal and spatial of inputs along the Vistula estuary and to the dilution of VOC-enriched river water with seawater. The concentrations of VOX in seawater decreased throughout the period and the concentrations of VOX were in the range of few ng dm(-3) up to 250 ng dm(-3), similar to estuaries elsewhere. The average concentrations of chlorophenols and phenoxyacids were between 0.1 and 6.0 and 0.05 and 2.2 microg dm(-3), respectively. However, remarkably high concentrations of 2,4-dichlorophenol (6 microg dm(-3)) were obtained in samples collected from the Vistula River. Generally concentrations of PCBs did not exceed few ng dm(-3) with the exception of 1999, when all samples exhibited elevated concentrations of PCBs. In addition, higher concentrations of PCBs in the open sea compared to river waters suggested localised inputs. Due to the ability of most organic pollutants to bioaccumulate and biomagnify, especially the persistent organic pollutants, continued monitoring is of crucial importance for the health of marine life in the Gulf of Gdańsk. 相似文献
99.
Iwona Jozwik Jacek Jagielski Grzegorz Gawlik Przemyslaw Jozwik Renata Ratajczak Gerard Panczer Nathalie Moncoffre Anna Wajler Agata Sidorowicz Lionel Thomé 《Physics and Chemistry of Minerals》2016,43(6):439-445
A comparative study of damage accumulation in magnesium aluminate spinel (MgAl2O4) has been conducted using ionoluminescence (IL), cathodoluminescence (CL) and Rutherford Backscattering Spectrometry/channeling (RBS/C) techniques. MgAl2O4 single crystal and polycrystalline samples were irradiated with 320 keV Ar+ ions at fluencies ranging from 1 × 1012 to 2 × 1016 cm?2 in order to create various levels of radiation damage. RBS/C measurements provided quantitative data about damage concentration in the samples. These values were then compared to the luminescence measurements. The results obtained by IL and RBS/C methods demonstrate a two-step character of damage buildup process. The CL data analysis points to the three-step damage accumulation mechanism involving the first defect transformation at fluencies of about 1013 cm?2 and second at about 1015 cm?2. The rate of changes resulting from the formation of nonluminescent recombination centers is clearly nonlinear and cannot be described in terms of continuous accumulation of point defects. Both, IL and CL techniques, appear as new, complementary tools bringing new possibilities in the damage accumulation studies in single- and polycrystalline materials. 相似文献
100.
Heat flow increases northward along Intermontane Belt in the western Canadian Cordillera, as shown by geothermal differences
between Bowser and Nechako sedimentary basins, where geothermal gradients and heat flows are ∼30 mK/m and ∼90 mW/m2 compared to ∼32 mK/m and 70 –80 mW/m2, respectively. Sparse temperature profile data from these two sedimenatary basins are consistent with an isostatic model
of elevation and crustal parameters, which indicate that Bowser basin heat flow should be ∼20 mW/m2 greater than Nechako basin heat flow. Paleothermometric indicators record a significant northward increasing Eocene or older
erosional denudation, up to ∼7 km. None of the heat generation, tectonic reorganization at the plate margin, or erosional
denudation produce thermal effects of the type or magnitude that explain the north–south heat flow differences between Nechako
and Bowser basins. The more southerly Nechako basin, where heat flow is lower, has lower mean elevation, is less deeply eroded,
and lies opposite the active plate margin. In contrast, Bowser basin, where heat flow is higher, has higher mean elevation,
is more deeply eroded, and sits opposite a transform margin that succeeded the active margin ∼40 Ma. Differences between Bowser
and Nechako basins contrast with the tectonic history and erosion impacts on thermal state. Tectonic history and eroded sedimentary
thickness suggest that Bowser basin lithosphere is cooling and contracting relative to Nechako basin lithosphere. This effect
has reduced Bowser basin heat flow by ∼10–20 mW/m2 since ∼40 Ma. Neither can heat generation differences explain the northerly increasing Intermontane Belt heat flow. A lack
of extensional structures in the Bowser basin precludes basin and range-like extension. Therefore, another, yet an unspecified
mechanism perhaps associated with the Northern Cordilleran Volcanic Province, contributes additional heat. Bowser basin’s
paleogeothermal gradients were higher, ∼36 mK/m, before the Eocene and this might affect petroleum and metallogenic systems. 相似文献