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1.
A simple parameter estimation procedure, designated as integration-based estimation (IBE), was introduced to determine the hydraulic properties of an aquifer using slug test models subjected to certain flow geometries such as radial and spherical flows. The basic idea behind the proposed IBE approach is to link an integration value at pre-defined normalized head levels for field data with that of a theoretical type curve. The IBE method removes the need for the implementation of the classical graphical matching process which would be ineffective to acquire aquifer parameters for non-ideal aquifer conditions. As the second aspect of this study, a new decision tool was suggested to determine the suitable slug test model to be utilized for the site data since diagnosing the flow character properly is of crucial importance for following a convenient analysis procedure. The estimation performance and limitation of the proposed IBE method were tested for several slug test scenarios including radial and spherical flow models with a number of synthetically generated data sets as well as a field application. Results reveal that the IBE together with the identification methodology not only is able to retrieve aquifer parameters as reliable as the existing techniques in the literature but also diagnoses the flow character precisely as demonstrated in this study.  相似文献   
2.
Astronomy Letters - We present LTE analysis of high resolution optical spectra for the B-type abundance standard candidate HD 35039 (HR 1765, 22 Ori) with an ambigous binary nature. The spectra...  相似文献   
3.
Coastal areas of the world are under treat due to the conflicting requirements of functions such as habitation and/or recreation, which affect the strategic asset of coastal scenery itself. Coastal managers, together with planners, need coastal landscape inventories, where the quality of coastal scenery is a part of the inventory. In order to provide an evidence-based approach for sound coastal management decisions, [Ergin et al., 2004] and [Ergin et al., 2006] developed a novel technique ‘coastal scenic evaluation’ (CSE), which addresses the evaluation of coastal scenery. The CSE technique utilizes fuzzy logic to derive values obtained from a checklist of 26 physical and human parameters. The methodology enables the calculation of an evaluation index (D), which categorizes the scenic values of coastal sites into five distinct classes. Using this technique, coastal scenic evaluations were carried out at 34 selected sites on the Western Black Sea coast of Turkey. Based on the calculated D values, a five-class differentiation was obtained for the selected sites, to provide baseline information for any envisaged subsequent management plans for these areas.  相似文献   
4.
Summary Contour maps of any meteorological variable cannot give radius or area of influences around the measurement station by considering the records at surrounding sites. The main purpose of this paper is to propose a trigonometric point cumulative semivariogram (TPCSV) concept for deciding on a spatial dependence function and then its use for regional prediction. The TPCSV provides a unique opportunity for the establishment of a regional objective prediction method whereby the radius of influence helps to predict wind velocity at any site by using the weighted averages. The spatial correlations and weightings are obtained through the TPCSV provided that the distance between two sites is known. If the slope of TPCSV is greater than 80° after some distance, then beyond this distance the regional correlation is considered as negligible. The implementation of the proposed methodology is presented for 68 wind velocity measurement stations in Turkey. The proposed method yields the least prediction error compared with other objective methodologies. It is seen that areas of influence at Central Anatolia are generally bigger than coastal areas of Turkey.  相似文献   
5.
This study introduces artificial neural networks (ANNs) for the estimation of land surface temperature (LST) using meteorological and geographical data in Turkey (26?C45°E and 36?C42°N). A generalized regression neural network (GRNN) was used in the network. In order to train the neural network, meteorological and geographical data for the period from January 2002 to December 2002 for 10 stations (Adana, Afyon, Ankara, Eski?ehir, ?stanbul, ?zmir, Konya, Malatya, Rize, Sivas) spread over Turkey were used as training (six stations) and testing (four stations) data. Latitude, longitude, elevation and mean air temperature are used in the input layer of the network. Land surface temperature is the output. However, land surface temperature has been estimated as monthly mean by using NOAA-AVHRR satellite data in the thermal range over 10 stations in Turkey. The RMSE between the estimated and ground values for monthly mean with ANN temperature(LSTANN) and Becker and Li temperature(LSTB-L) method values have been found as 0.077?K and 0.091?K (training stations), 0.045?K and 0.003?K (testing stations), respectively.  相似文献   
6.
We present an LTE analysis of high resolution echelle optical spectra obtained with the 3.9-m Anglo-Australian Telescope (AAT) and the UCLES spectrograph for a B1Ib high galactic latitude supergiant HD119608. A fresh determination of the atmospheric parameters using line-blanketed LTE model atmospheres and spectral synthesis provided Teff = 23 300 ± 1000 K, log g = 3.0 ± 0.3, and the microturbulent velocity ξ = 6.0 ± 1.0 kms?1 and [Fe/H] = 0.16. The rotational velocity of the star was derived fromC, O, N, Al, and Fe lines as v sin i = 55.8 ± 1.3 kms?1. Elemental abundances were obtained for 10 different species. He, Al, and P abundances of the star were determined for the first time. In the spectra, hot post-AGB status as well as the Pop I characteristics of the star were examined. The approximately solar carbon and oxygen abundances, along with mild excess in helium and nitrogen abundances do not stipulate a CNO processed surface composition, hence a hot post-AGB status. The LTE abundances analysis also indicates solar sulphur and moderately enriched magnesium abundances. The average abundances of B dwarfs of well studied OB associations and Population I stars show a striking resemblance to abundances obtained for HD119608 in this study. This may imply a runaway status for the star.  相似文献   
7.
Saudi Arabia possesses numerous low-grade gold deposits and many occurrences are located in the Arabian Shield. Currently, there are five operating gold mines and major plans are underway to develop three gold mining regions in various parts of the shield. Because of the presence of numerous deposits and a significant amount of investments earmarked for the development of these deposits by the Saudi Government during the last few years, Saudi Arabia is expected to become one of the leading gold producers in the world. This paper starts with an introduction of gold mineralization and mining activities in the Arabian Shield in a historical perspective. This is followed by a brief review of geology and the geological importance of the Arabian Shield as a host for various types of gold deposits. The latter part of the paper discusses the statistical distribution of gold grades and its impact on cutoff grade variations on the gold reserves and their mining potentials. Finally, considering the lognormal distribution of gold grades and reduction in cutoff grades, it is demonstrated how some of the previously classified uneconomic resources can be gradually converted into mineable reserves with increasing proportions.  相似文献   
8.
In the semi-arid steppe rangelands of Central Turkey, Festuca valesiaca and Thymus sipyleus ssp rosulans have become the dominant species on degraded pastures. We hypothesized that decreases in species richness and abundance are correlated with increasing prevalence of these two species. Therefore, our objectives were to determine whether there are patterns in examined vegetation; how dominant species contribute to these patterns; and how patterns differ between grazed and ungrazed vegetation. We determined that protection from grazing increased species richness. Grazing significantly changed composition through decreasing total plant, forb, grass and F. valesiaca covers, while substantially increasing T. sipyleus cover. Topography, soil and grazing appear to impact the dominance of plant communities where F. valesiaca and T. sipyleus prevail. These two dominant species had a significant effect in shaping vegetation patterns. Based on regression analysis, alterations in species richness with changes in cover of forbs and shrubs were evident, and spatial heterogeneity of F. valesiaca and T. sipyleus indicated unstable vegetative patterns in heavily grazed pastures and successional changes in protected pastures. Our study results identify F. valesiaca and T. sipyleus as indicator species of vegetation suppression in condition assessments of degraded steppe rangelands.  相似文献   
9.
Within the framework of the National Marine Geological and Geophysical Program, we re‐examined deep vertical electrical sounding (VES) data. The data, measured in 1968 by the General Directorate of Mineral Research and Exploration (MTA) of Turkey with the aim of exploring the deep resistivity structure of the Dikili–Bergama region, focus on the geothermal potential. The geoelectrical resistivity survey was conducted using a Schlumberger array with a maximum electrode half‐spacing of 4.5 km. The two‐dimensional (2D) inversion was utilized to interpret the VES data that were collected along 15‐ to 30‐km profiles. The 2D resistivity–depth cross‐sections obtained show very low resistivity values near the Dikili and Kaynarca hot springs. The 2D inversion results also indicate the presence of fault zones striking nearly N–S and E–W, and fault‐bounded graben‐horst structures that show promising potential for geothermal field resources. The 2D gravity model, which is in good agreement with the density variation of the region, supports the resistivity structure revealed by 2D inversion. The lithology information obtained from the borehole near Kaynarca also confirms the results of the resistivity interpretation and the density model.  相似文献   
10.
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