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71.
Gülhan Özbayoğlu A. Murat Özbayoğlu M. Evren Özbayoğlu 《International Journal of Mineral Processing》2008
In this research, different techniques for the estimation of coal HGI values are studied. Data from 163 sub-bituminous coals from Turkey are used by featuring 11 coal parameters, which include proximate analysis, group maceral analysis and rank. Non-linear regression and neural network techniques are used for predicting the HGI values for the specified coal parameters. Results indicate that a hybrid network which is a combination of 4 separate neural networks gave the most accurate HGI prediction and all of the neural network models outperformed non-linear regression in the estimation process. 相似文献
72.
The aim of this study was to do a preliminary assessment of the hydrochemical and microbial groundwater quality of the West
Thrace region. Forty samples of groundwater collected from Edirne (Site 1) to Gelibolu (Site 2) were assessed for their suitability
for human consumption. As3− was non-detectable in all the groundwater and Zn2+, Pb2+, F−, Cu2+, NH4+, Cn− PO43− and Cl− were all below their respective European Union drinking water directive (EU-DWD) and Turkish food codex-drinking water directive
(TFC-DWD). Maximum Acceptable Concentrations (MAC) Ni2+, Pb2+, Cd2+, Mg2+, Mn2+, and Ca2+ levels were detected in upper maximum acceptable concentrations 77.5, 42.5, 35.0, 50.0, 50.0, and 32.5% of the groundwater
samples, respectively. However, in terms of Cr3+, Ni2+ and Pb2+, the differences between groundwaters of Sites 1 and 2 were significant (p < 0.05). Eight water samples (20%) had HPC exceeding the EU and Turkish water directive limit 20 CFU (Colony Forming Unit)/ml
in drinking water and the maximum bacteria count recorded was 44 CFU/ml. Total coliforms, thermotolerant coliforms, E. coli, Enterococcus spp., Salmonella sp., Staphylococcus spp. and P. aeruginosa were detected in 25, 17.5, 15, 47.5, 15, 27.5, and 15% of the groundwater samples, respectively. Furthermore, heavy metals
and trace elements were found after chemical analyzes in most samples. The pollution of groundwater come from a variety of
sources, Meric and Ergene rivers, including land application of agricultural chemicals and organics wastes, infiltration of
irrigation water, septic tanks, and infiltration of effluent from sewage treatment plants, pits, lagoons and ponds used storage. 相似文献
73.
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76.
A new approach to use AHP in landslide susceptibility mapping: a case study at Yenice (Karabuk, NW Turkey) 总被引:9,自引:4,他引:5
This study aimed to investigate the parameter effects in preparing landslide susceptibility maps with a data-driven approach and to adapt this approach to analytical hierarchy process (AHP). For this purpose, at the first stage, landslide inventory of an area located in the Western Black Sea region of Turkey covering approximately 567?km2 was prepared, and a total of 101 landslides were mapped. In order to assess the landslide susceptibility, a total of 13 parameters were considered as the input parameters: slope, aspect, plan curvature, topographical elevation, vegetation cover index, land use, distance to drainage, distance to roads, distance to structural elements, distance to ridges, stream power index, sediment transport capacity index, and wetness index. AHP was selected as the major assessment methodology since the adapted approach and AHP work in data pairs. Adapted to AHP, a similarity relation?Cbased approach, namely landslide relation indicator (LRI) for parameter selection method, was also proposed. AHP and parametric effect analyses were performed by the proposed approach, and seven landslide susceptibility maps were produced. Among these maps, the best performance was gathered from the landslide susceptibility map produced by 9 parameter combinations using area under curve (AUC) approach. For this map, the AUC value was calculated as 0.797, while the others ranged between 0.686 and 0.771. According to this map, 38.3?% of the study area was classified as having very low, 8.5?% as low, 15.0?% as moderate, 20.3?% as high, and 17.9?% as very high landslide susceptibility, respectively. Based on the overall assessments, the proposed approach in this study was concluded as objective and applicable and yielded reasonable results. 相似文献
77.
S. Reis A. Yalcin M. Atasoy R. Nisanci T. Bayrak M. Erduran C. Sancar S. Ekercin 《Environmental Earth Sciences》2012,66(7):2063-2073
The northeast part of Turkey is prone to landslides because of the climatic conditions, as well as geologic and geomorphologic
characteristics of the region. Especially, frequent landslides in the Rize province often result in significant damage to
people and property. Therefore, in order to mitigate the damage from landslides and help the planners in selecting suitable
locations for implementing development projects, especially in large areas, it is necessary to scientifically assess susceptible
areas. In this study, the frequency ratio method and the analytical hierarchy process (AHP) were used to produce susceptibility
maps. Especially, AHP gives best results because of allowing better structuring of various components, including both objective
and subjective aspects and comparing them by a logical and thorough method, which involves a matrix-based pairwise comparison
of the contribution of different factors for landslide. For this purpose, lithology, slope angle, slope aspect, land cover,
distance to stream, drainage density, and distance to road were considered as landslide causal factors for the study area.
The processing of multi-geodata sets was carried out in a raster GIS environment. Lithology was derived from the geological
database and additional field studies; slope angle, slope aspect, distance to stream, distance to road and drainage density
were invented from digital elevation models; land cover was produced from remote sensing imagery. In the end of study, the
results of the analysis were verified using actual landslide location data. The validation results showed satisfactory agreement
between the susceptibility map and the existing data on landslide locations. 相似文献
78.
A Simplified Failure Criterion for Intact Rocks Based on Rock Type and Uniaxial Compressive Strength 总被引:2,自引:1,他引:1
Jiayi Shen Rafael Jimenez Murat Karakus Chaoshui Xu 《Rock Mechanics and Rock Engineering》2014,47(2):357-369
The uniaxial compressive strength (UCS) of intact rock, which can be estimated using relatively straightforward and cost-effective techniques, is one of the most practical rock properties used in rock engineering. Thus, constitutive laws to represent the strength and behavior of (intact) rock frequently use it, along with additional intrinsic rock properties. Although triaxial tests can be employed to obtain best-fit failure criterion parameters that provide best strength predictions, they are more expensive and require time-consuming procedures; as a consequence, they are often not readily available at early stages of a project. Based on the analysis of an extensive triaxial test database for intact rocks, we propose a simplified empirical failure criterion in which rock strength at failure is expressed in terms of confining stress and UCS, with a new parameter which can be directly estimated from the UCS for a specified rock type in the absence of triaxial test data. Performance of the proposed failure criterion is then tested for validation against experimental data for eight rock types. The results show that strengths of intact rock estimated by the proposed failure criterion are in good agreement with experimental test data, with small discrepancies between estimated and measurements strengths. Therefore, the proposed criterion can be useful for preliminary (triaxial) strength estimation of intact rocks when triaxial tests data are not available. 相似文献
79.
Adem Bayram Hızır Önsoy Murat İhsan Kömürcü Mehmet Tüfekçi 《Environmental Earth Sciences》2014,72(8):2849-2860
This paper aims to reveal the reciprocal influence of Kürtün Dam and wastewaters from the settlements on the water quality in the stream Har?it, NE Turkey. Several key water-quality indicators were measured: water temperature (T), pH, dissolved oxygen (DO), electrical conductivity, water hardness, chemical oxygen demand (COD), ammonium nitrogen (NH4 +–N), nitrite nitrogen (NO2 ?–N), nitrate nitrogen (NO3 ?–N), total Kjeldahl nitrogen (TKN), total nitrogen (TN), orthophosphate phosphorus (PO4 3?–P), and methylene blue active substances (MBAS). The monitoring and sampling studies were conducted every 15 days from March 2009 to February 2010 at two stations selected in the upstream and downstream of the Kürtün Dam. It was concluded that the Kürtün Dam Lake had a high-quality water in terms of T, pH, DO, COD, NH4 +–N, NO2 ?–N and NO3 ?–N values, but slightly polluted water with respect to TKN, PO4 3?–P, and MBAS according to the Turkish Water Pollution Control Regulation. The dam improved the stream water quality by increasing the DO concentration, and decreasing the NO2 ?–N and PO4 3?–P concentrations thanks to its hydraulic residence time despite the wastewater discharge by the nearby settlements. However, the wastewater discharge deteriorated the stream water quality increasing the COD, NH4 +–N, NO3 ––N, and TN concentrations. 相似文献
80.
Ibrahim Sönmez Ahmet Emre Tekeli Erdem Erdi Fatih Demir Murat Arslan 《Arabian Journal of Geosciences》2014,7(8):3389-3398
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