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91.
92.
Three-dimensional (3-D) representations of urban regions have gained much attention because of recent developments in remote sensing and computer graphics technologies. In particular, textured 3-D building reconstruction for a variety of applications has been a popular research topic in recent years. In this study, we present the reconstruction of 3-D building models along with texture selection and mapping. Extracted two-dimensional building patches and normalized digital surface model (nDSM) data are used to generate the 3-D models. To build near-photorealistic 3-D models, the acquired geo-referenced facade textures are associated with the corresponding building facades using an automated GPS-assisted approach. On the other hand, the modelling and texture mapping of the roof structures were carried out manually. The study area is composed of eight housing estates (blocks), where a total of 110 buildings were analysed. The whole study area was modelled, with facade textures, in less than 1 min of processor running time with an acceptable level of accuracy. The texture mapping was carried out using MATLAB’s Virtual Reality Toolbox?. 相似文献
93.
Tributyltin and triphenyltin induce spermatogenesis in ovary of female abalone,Haliotis gigantea 总被引:1,自引:0,他引:1
Horiguchi T Kojima M Kaya M Matsuo T Shiraishi H Morita M Adachi Y 《Marine environmental research》2002,54(3-5):679-684
Two-month flow-through exposure experiments of tributyltin (TBT) and triphenyltin (TPhT) were conducted with abalone, Haliotis gigantea. Nominal concentrations of 100 ng TBT/l and 100 ng TPhT/l caused significant spermatogenesis in ovaries of exposed females. There were also significantly more contracted primary oocytes observed in females exposed to either TBT or TPhT than controls. The incidence of two types of unknown cells was also significant in females exposed to TPhT. No significant histological changes were observed in testis of exposed males. This ovarian spermatogenesis caused by TBT and/or TPhT resembles gastropod imposex. Remarkably high concentrations of TBT and TPhT were observed in the head (including central nervous system ganglia), compared to muscles concentrations. Accumulation of TBT and TPhT in the head may disturb reproductive hormonal regulators through neuropeptides released from ganglia. This, as well as possible aromatase inhibition, may be one of the inducers for spermatogenesis in the abalone ovaries. 相似文献
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95.
An artificial neural networks (ANN) model is developed to study the observed pattern of local scour at bridge piers using an FHWA (Federal Highway Administration) data set composed of 380 measurements at 56 bridges in 13 states. Various ANN estimates of observed pier scour depth on different choices of input variables are examined. Reducing the number of variables from 14 to 9 has negligible effect on the coefficient of determination, R2, (0.73 vs. 0.72). Further sensitivity analysis indicates that pier scour depth can be estimated using only four variables: pier shape and skew, flow depth and velocity with a coefficient of determination of 0.81, suggesting that inclusion of some variables actually diminishes the quality of ANN predictions of short term observed pattern of scour. The ANN estimates indicate that flow depth and flow velocity make up 66% of the coefficient of determination. 相似文献
96.
97.
Heavy metal pollution and acid drainage from the abandoned Balya Pb-Zn sulfide Mine,NW Anatolia,Turkey 总被引:5,自引:0,他引:5
Atilla?Aykol Murat?BudakogluEmail author Mustafa?Kumral Ali?H.Gultekin Melih?Turhan Vildan?Esenli Fuat?Yavuz Yuksel?Orgun 《Environmental Geology》2003,45(2):198-208
This study was conducted to determine the effects of the waste-rock dump (WRD) of the underground polymetallic Balya Mine on the Kocacay River and eventually on Lake Manyas in Turkey. Data presented in this paper include geochemical characteristics of various kinds of water (mine, surface and groundwater) and of suspended-particle samples in the vicinity of Balya. The more polluted mine waters have low pH and high conductivity, while high concentrations of Zn, Cd, Mn tend to be found in the dry and wet seasons. High concentrations of Pb, As, Cr, Cu and S appear only in the wet season. The sources of the heavy metal concentration within the Kocacay River are leached waste, surface run off, and overflow from the spillway of the WRD. To minimize the formation of acids and dissolved metal, and for the remediation of the harmful effects of extreme contamination conditions, it is recommended that lime or alkali materials and organic carbon be added to simulate the action of sulfate-reducing bacteria. 相似文献
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99.
Istanbul is the largest city in Turkey with an area of around 5750 km2 and a population of around 10.8 M (2000). In 1980, the population was only around 4.7 M and so has more than doubled in only 2 decades. In 2000, around 65% of the population were living on the European side of the city with its large industrial/commercial and trade centres. The population is increasing as a result of both births exceeding deaths and mass immigration. Consequently, planned and unplanned housing are increasing while green areas are decreasing in area. Monitoring urban growth will enable the Municipality of Istanbul to better manage this complex urban area. 相似文献
100.
Stochastic fractal (fGn and fBm) porosity and permeability fields are conditioned to given variogram, static (or hard), and multiwell pressure data within a Bayesian estimation framework. Because fGn distributions are normal/second-order stationary, it is shown that the Bayesian estimation methods based on the assumption of normal/second-order stationary distributions can be directly used to generate fGn porosity/permeability fields conditional to pressure data. However, because fBm is not second-order stationary, it is shown that such Bayesian estimation methods can be used with implementation of a pseudocovariance approach to generate fBm porosity/permeability fields conditional to multiwell pressure data. In addition, we provide methods to generate unconditional realizations of fBm/fGn fields honoring all variogram parameters. These unconditional realizations can then be conditioned to hard and pressure data observed at wells by using the randomized maximum likelihood method. Synthetic examples generated from one-, two-, and three-dimensional single-phase flow simulators are used to show the applicability of our methodology for generating realizations of fBm/fGn porosity and permeability fields conditioned to well-test pressure data and evaluating the uncertainty in reservoir performance predictions appropriately using these history-matched realizations. 相似文献