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51.
Interoperability is becoming essential for the today’s geographic information systems. Geographic information is usually available as datasets stored in databases and accessible via GIS. However, these information sources are increasingly heterogeneous and show differences in data formats, database schema and object concepts. To satisfy the increased demand for the use and sharing of geographic data in common applications, considering the heterogeneity and the methods to support interoperability are required by the GIS community. The implementation of Spatial Data Infrastructure (SDI) such as the European INSPIRE (Infrastructure for Spatial Information in the European Community) enables accessibility and the sharing of geographic data and interoperability among the systems. In addition to this, traditional GIS systems perform spatial queries using a keyword-based method. However, this approach remains incapable of fully expressing the users' needs due to a lack of geographic concepts (semantics) in the dataset. Different terms may refer to similar concepts, while the same terms may refer to different concepts. This causes semantic heterogeneity in the dataset. In this context, the most promising approach is the implementation of geospatial semantics by means of ontology in the geospatial dataset to overcome this kind of ambiguity. The aim of this research is to investigate the implementation of INSPIRE as a SDI standard and the use of Semantic Technology to empower the traditional GIS approach. In this regard, a public transportation geoportal has been developed for the experimental investigation which uses a revised sample transportation data complaint with the INSPIRE Transport Network Data Theme and a developed Transportation Ontology Domain, including concepts, relationships and individuals to provide a semantic spatial search.  相似文献   
52.
Western Turkey is one of the most spectacular regions of widespread, active continental extension in the world. The most prominent structures of this region are E–W trending Gediz and Büyük Menderes Grabens. Geothermal activity around city of Manisa in Gediz Graben has been investigated by many researchers and many geothermal boreholes were drilled in order to produce electricity. In the middle of May 2012, a geothermal blowout occurred 150 m away from the deep drilling (depth 1,100 m), in Alkan village of Ala?ehir resort in city of Manisa. After that, four big blowouts took place at the same area and thermal water had been diverted to Alkan stream for almost 4 months. The boron (B) and Fe levels of thermal water are 87 and 11.2 ppm where the background B and Fe values of topsoil vary between 0.2–1.5 ppm and 3.08–5.63 ppm, respectively. The objective of this study was to utilize joint magnetic susceptibility and VLF-R investigations to determine possibly contaminated area with B, related to high Fe level on the topsoil and thermal water in the subterranean layers. It is observed that magnetic susceptibility values vary between 500 and 790 cgs (×10?6) in the vicinity of blowouts and 150–340 cgs (×10?6) at a distance of 50 m around, where the background average value is 20 cgs (×10?6), by using the data collected at 346 stations. Besides, the VLF-R studies were carried out along 18 profiles at three different frequencies. Laterally constrained two-layer inversion was applied to each station; in addition to the inversion of all profiles for each frequency, all lines were stacked, 2-D resistivity maps were obtained, and the contaminated area was determined approximately as 35,000 m2. The results show not only satisfactory agreement between magnetic susceptibility and VLF-R data, but also provide fast and valued interpretation of geochemical and geophysical properties of the geothermal contaminated area.  相似文献   
53.
Validation of the active fire monitoring (FIR) product from Spinning Enhanced Visible and Infrared Imager sensor of Meteosat Second Generation satellite is performed over Turkey. Ground truth data from the Ministry of Environment and Forestry for the years 2007, 2008, and 2009 is used by taking the active fire months of April–September into consideration. The contingency tables are obtained on a monthly basis and categorical statistics of probability of detection (POD) and false alarm rate (FAR) are derived. The results are introduced for each subclass, namely probable, possible, and combined cases. The highest POD amounts of 8.5, 1.93, and 9.4 % are obtained for the possible, probable, and combined cases, respectively, with the lowest FAR amounts of 70.9, 4.5, and 86.1 % for the same categories. FIR product validation with respect to predefined burnt area thresholds is introduced in the second part of the study in order to investigate burnt area effect in active fire detection. Increasing POD values with respect to burnt area amount is obtained with relatively higher values in probable than possible type. On the other hand, FAR variation is observed to be not correlated with the burnt area amount.  相似文献   
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This paper presents the effects of addition of lime and lime along with gypsum on the compressibility behavior of two class F fly ashes. Since the fly ashes develop strength and exhibit lower compression, consolidation testing with conventional duration of load increment may not be appropriate. Hence, an attempt has been made to assess the minimum duration of load increment necessary to study the compressibility characteristics of such materials. Thus compressibility behavior of fly ashes with additives has been studied using conventional consolidation test with different durations of load increments varying from 30 min to 48 h. The results obtained indicated that 30 min of duration of load increment can be used to assess the compressibility behavior of such materials. The effect of lime which reduces the compression is seen to be maximum from the results obtained with the duration of load increment of 30 min but gradually reduces with higher durations of load increment. It has also been observed that the rate of decrease in the compressibility is maximum up to 2.5% lime and gradual thereafter. The compressibility of lime treated fly ashes further reduces when gypsum is incorporated, the optimum gypsum percentage being 2.5. This reduction in the compressibility of fly ashes enhanced by incorporating lime and gypsum makes them versatile in the construction of embankments and for structural fills, particularly reducing the time required in between laying of each lift.  相似文献   
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Remotely sensed data may provide easy access for monitoring the spatial separation and obtaining the hydrodynamic characteristics of turbid freshwater plumes created by river flow in the marine environment. Traditional methods are time consuming and require great effort to produce sufficient data. In this project, integrated research has been carried out on a river to demonstrate the utility of remote sensing (RS) technology for studying fundamental theoretical properties of turbulent mixtures. The Filyos River mouth, located on the Black Sea coast of Turkey, is the research area. Flow properties, such as the horizontal dispersion coefficient, have been calculated (using Landsat TM sensor images taken on two different dates). The effects of the plume on the morphology of neighbouring beaches are also examined. This study shows the utility of RS technology for generating quantitative data and better defining the hydraulic behaviour of a river with high turbidity. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
58.
Bodies of magnesite-rich rocks (magnesite ± talc ± quartz ± dolomite), locally containing emerald deposits, occur within the Swat Valley. These rocks, part of the Indus suture mélange group, are distributed mostly along contacts of serpentinized ultramafic rocks with carbonate ± graphite-bearing metasedimentary rocks. Their field association, petrographic details, mineralogical composition and geochemical characteristics show that they likely formed due to carbonate alteration of previously serpentinized ultramafic rocks by CO2-bearing fluids released as a result of metamorphism of spatially associated, originally sedimentary rocks of the Indo-Pakistan plate.Locally, late-stage hydrothermal activity affected these highly fissile magnesite-rich rocks to produce veins and stockworks of quartz as well as emerald, Cr-rich tourmaline and Cr, Ni-rich muscovite. Detailed petrographic and mineral chemical investigations suggest that all three Cr-bearing silicates are genetically related and their Cr, as well as Ni and Mg found in Cr-rich muscovite and Cr-rich tourmaline, was derived from the original ultramafic protoliths.Detailed geochemical comparison reveals that relative to non-mineralized sections, magnesite-rich rocks in mineralized zones show significant enrichment in B and Be as well as As, Pb, Zr, Rb, Ba, W, Sn, Sr and Y. Boron and Be enrichment in these rocks appears to be structurally controlled. More extreme B and Be enrichment is evident in small granitic dikes cutting granite gneisses and in Miocene leucogranitic stocks at Malakand 45 km southwest. These geochemical features argue strongly for a leucogranite-associated source for Be-transporting fluids to the emerald's host rocks.  相似文献   
59.
To determine whether the inclusion of spatial neighbourhood comparison factors in Preference Modelling allows spatial decision support systems (SDSSs) to better address spatial equity, we introduce Spatial Preference Modelling (SPM). To evaluate the effectiveness of this model in addressing equity, various standardisation functions in both Non-Spatial Preference Modelling and SPM are compared. The evaluation involves applying the model to a resource location-allocation problem for transport infrastructure in the Special Province of Yogyakarta in Indonesia. We apply Amartya Sen’s Capability Approach to define opportunity to mobility as a non-income indicator. Using the extended Moran’s I interpretation for spatial equity, we evaluate the distribution output regarding, first, ‘the spatial distribution patterns of priority targeting for allocation’ (SPT) and, second, ‘the effect of new distribution patterns after location-allocation’ (ELA). The Moran’s I index of the initial map and its comparison with six patterns for SPT as well as ELA consistently indicates that the SPM is more effective for addressing spatial equity. We conclude that the inclusion of spatial neighbourhood comparison factors in Preference Modelling improves the capability of SDSS to address spatial equity. This study thus proposes a new formal method for SDSS with specific attention on resource location-allocation to address spatial equity.  相似文献   
60.
The purpose of this study was to investigate the capabilities of different landslide susceptibility methods by comparing their results statistically and spatially to select the best method that portrays the susceptibility zones for the Ulus district of the Bart?n province (northern Turkey). Susceptibility maps based on spatial regression (SR), linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), logistic regression (LR) method, and artificial neural network method (ANN) were generated, and the effect of each geomorphological parameter was determined. The landslide inventory map digitized from previous studies was used as a base map for landslide occurrence. All of the analyses were implemented with respect to landslides classified as rotational, active, and deeper than 5 m. Three different sets of data were used to produce nine explanatory variables (layers). The study area was divided into grids of 90 m × 90 m, and the ‘seed cell’ technique was applied to obtain statistically balanced population distribution over landslide inventory area. The constructed dataset was divided into two datasets as training and test. The initial assessment consisted of multicollinearity of explanatory variables. Empirical information entropy analysis was implemented to quantify the spatial distribution of the outcomes of these methods. Results of the analyses were validated by using success rate curve (SRC) and prediction rate curve (PRC) methods. Additionally, statistical and spatial comparisons of the results were performed to determine the most suitable susceptibility zonation method in this large-scale study area. In accordance with all these comparisons, it is concluded that ANN was the best method to represent landslide susceptibility throughout the study area with an acceptable processing time.  相似文献   
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