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Is there a limit to bioretention effectiveness? Evaluation of stormwater bioretention treatment using a lumped urban ecohydrologic model and ecologically based design criteria 下载免费PDF全文
Olivia M. Wright Erkan Istanbulluoglu Richard R. Horner Curtis L. DeGasperi Jim Simmonds 《水文研究》2018,32(15):2318-2334
In this study, we developed the urban ecohydrology model (UEM) to investigate the role of bioretention on watershed water balance, runoff production, and streamflow variability. UEM partitions the land surface into pervious, impervious, and bioretention cell fractions. Soil moisture and vegetation dynamics are simulated in pervious areas and bioretention cells using a lumped ecohydrological approach. Bioretention cells receive runoff from a fraction of impervious areas. The model is calibrated in an urban headwater catchment near Seattle, WA, USA, using hourly weather data and streamflow observations for 3 years. The calibrated model is first used to investigate the relationship between streamflow variability and bioretention cell size that receives runoff from different values of impervious area in the watershed. Streamflow variability is quantified by 2 indices, high pulse count (HPC), which quantifies the number of flow high pulses in a water year above a threshold, and high pulse range (HPR), which defines the time over which the pulses occurred. Low values of these indices are associated with improved stream health. The effectiveness of the modelled bioretention facilities are measured by their influence on reducing HPC and HPR and on flow duration curves in comparison with modelled fully forested conditions. We used UEM to examine the effectiveness of bioretention cells under rainfall regimes that are wetter and drier than the study area in an effort to understand linkages between the degree of urbanization, climate, and design bioretention cell size to improve inferred stream health conditions. In all model simulations, limits to the reduction of HPC and HPR indicators were reached as the size of bioretention cells grew. Bioretention was more effective as the rainfall regime gets drier. Results may guide bioretention design practices and future studies to explore climate change impacts on bioretention design and management. 相似文献
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The motion response prediction of offshore structures may be carried out using time domain or frequency domain models or model tests. The frequency domain analysis uses the simplified, linearised form of the motion equations and it is very economical. The time domain analysis, unlike frequency domain models, is adequate to deal with non-linearities such as viscous damping and mooring forces, but it requires sophisticated solution techniques and it is expensive to employ. For moored semisubmersibles time domain techniques must be employed since there are strong nonlinearities in the system due to mooring line stiffness and damping and viscous drag forces. In the first part of this paper a time domain model to predict the dynamic response of a semi-submersibles are developed and the effect of thrusters and mooring line damping are incorporated into the time domain model. In the second part time domain simulations are carried out to find the total extreme motions and mooring forces. 相似文献
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B. Albayrak G. Djurašević S. Selam M. Yilmaz S. Erkapić O. Aksu T. Tanriverdi 《Astrophysics and Space Science》2005,296(1-4):293-296
BVR light curves of the recently discovered eclipsing binary V351 Peg were studied to derive the preliminary physical parameters
of the system. The light curves were obtained at the TüBİTAK* – Turkish National Observatory (TUG) during three nights in
August, 2003. The solutions were made using Djurašević’s inverse problem method. V351 Peg is a system in an overcontact configuration
(f
over∼ 21 %) with a relatively small temperature difference between the components ΔT ≈ 20 K. The results suggest a significant mass and energy transfer from the more massive primary onto the less massive secondary.
The hot area on the less massive star, near the neck region, can be considered as a consequence of this mass and energy exchange
between the components through the connecting neck of the common envelope.
TüBİTAK: The Scientific and Technical Research Council of Turkey. 相似文献
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The effect of the sampling strategies on the landslide susceptibility mapping by conditional probability and artificial neural networks 总被引:4,自引:2,他引:2
Işık Yilmaz 《Environmental Earth Sciences》2010,60(3):505-519
This study presented herein compares the effect of the sampling strategies by means of landslide inventory on the landslide
susceptibility mapping. The conditional probability (CP) and artificial neural networks (ANN) models were applied in Sebinkarahisar
(Giresun–Turkey). Digital elevation model was first constructed using a geographical information system software and parameter
maps affecting the slope stability such as geology, faults, drainage system, topographical elevation, slope angle, slope aspect,
topographic wetness index, stream power index and normalized difference vegetation index were considered. In the last stage
of the analyses, landslide susceptibility maps were produced applying different sampling strategies such as; scarp, seed cell
and point. The maps elaborated were then compared by means of their validations. Scarp sampling strategy gave the best results
than the point, whereas the scarp and seed cell methods can be evaluated relatively similar. Comparison of the landslide susceptibility
maps with known landslide locations indicated that the higher accuracy was obtained for ANN model using the scarp sampling
strategy. The results obtained in this study also showed that the CP model can be used as a simple tool in assessment of the
landslide susceptibility, because input process, calculations and output process are very simple and can be readily understood. 相似文献
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H. Gonca Coskun Ozlem Gulergun Levent Yilmaz 《International Journal of Applied Earth Observation and Geoinformation》2006
In this study, remote sensing (RS) with computer-based geographic information systems (GIS) techniques are used as a tool for monitoring the water basin area and water quality in Istanbul's relatively less polluted and comparatively less destroyed catchment of the metropolis drinking water dam reservoir named Terkos. It is necessary to work with recent data to be able to identify the effects of urbanization on the water quality of the Terkos dam catchment area that supplies drinking water to the metropolis. RS is an important tool to monitor water quality and urban terrain. For this aim, a project has been initiated at the Technical University Remote Sensing Laboratory, under the Istanbul Water and Sewerage Administration (ISKI) sponsorship in Istanbul. The project uses SPOT-PAN, XS and IRS-1C/D PAN and satellite data of 1993 and 2000 for urban analysis and Landsat-TM and LISS-III satellite data of 1992 and 2000 for water quality. For calibration and validation, ground truth samples are collected from the experimental area. The RS data was converted into the UTM coordinate system and image enhancement and classification techniques are used. Raster data is converted to vector data to assess the study area for analyzing in GIS for the purpose of planning and decision-making on protected water basin zones. As a result of monitoring land use and water quality changes, recommendations are made for planning and management of the protected environment of the Terkos catchment protected area. Measuring land use change is a very important issue for controlling the future development of the basin, GIS techniques are performed and results are illustrated in established models on the four protected zones of Terkos water basin. 相似文献
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Mount Hasan is a double-peaked stratovolcano, located in Central Anatolia, Turkey. The magmas erupted from this multi-caldera complex range from basalt to rhyolite, but are dominated by andesite and dacite. Two terminal cones (Big Mt. Hasan and Small Mt. Hasan) culminate at 3253 m and 3069 m respectively. There are four evolutionary stages in the history of the volcanic complex (stage 1: Kecikalesi volcano, 13 Ma, stage 2: Palaeovolcano, 7 Ma, stage 3: Mesovolcano and stage 4: Neovolcano). The eruptive products consist of lava flows, lava domes, and pyroclastic rocks. The later include ignimbrites, phreatomagmatic intrusive breccias and nuées ardentes, sometimes reworked as lahars. The total volume is estimated to be 354 km3, the area extent 760 km2. Textural and mineralogical data suggest that both magma mixing and fractional crystallization were involved in the generation of the andesites and dacites. The magmas erupted from the central volcanoes show a transition with time from tholeite to calc-alkaline. Three generations of basaltic strombolian cones and lava flows were emplaced contemporaneously with the central volcanoes. The corresponding lavas are alkaline with a sodic tendency. 相似文献