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81.
Deformation models for image recognition 总被引:2,自引:0,他引:2
Keysers D Deselaers T Gollan C Ney H 《IEEE transactions on pattern analysis and machine intelligence》2007,29(8):1422-1435
We present the application of different nonlinear image deformation models to the task of image recognition. The deformation models are especially suited for local changes as they often occur in the presence of image object variability. We show that, among the discussed models, there is one approach that combines simplicity of implementation, low-computational complexity, and highly competitive performance across various real-world image recognition tasks. We show experimentally that the model performs very well for four different handwritten digit recognition tasks and for the classification of medical images, thus showing high generalization capacity. In particular, an error rate of 0.54 percent on the MNIST benchmark is achieved, as well as the lowest reported error rate, specifically 12.6 percent, in the 2005 international ImageCLEF evaluation of medical image specifically categorization. 相似文献
82.
The Dynamics of Syntactic Knowledge 总被引:1,自引:0,他引:1
The syntactic approach to epistemic logic avoids the logicalomniscience problem by taking knowledge as primary rather thanas defined in terms of possible worlds. In this study, we combinethe syntactic approach with modal logic, using transition systemsto model reasoning. We use two syntactic epistemic modalities:knowing at least a set of formulae and knowingat most a set of formulae. We are particularly interestedin models restricting the set of formulae known by an agentat a point in time to be finite. The resulting systems are investigatedfrom the point of view of axiomatization and complexity. Weshow how these logics can be used to formalise non-omniscientagents who know some inference rules, and study their relationshipto other systems of syntactic epistemic logics, such as Ågotnesand Walicki (2004, Proc. 2nd EUMAS, pp. 110), Alechinaet al. (2004, Proc. 3rd AAMAS, pp. 601613), Duc (1997,J. Logic Comput., 7, 633648). 相似文献
83.
Burwick T 《Neural computation》2006,18(2):356-380
Using an oscillatory network model that combines classical network models with phase dynamics, we demonstrate how the superposition catastrophe of pattern recognition may be avoided in the context of phase models. The model is designed to meet two requirements: on and off states should correspond, respectively, to high and low phase velocities, and patterns should be retrieved in coherent mode. Nonoverlapping patterns can be simultaneously active with mutually different phases. For overlapping patterns, competition can be used to reduce coherence to a subset of patterns. The model thereby solves the superposition problem. 相似文献
84.
Pradeep K. Nalla Roland J. Weiss Prakash Peranandam Jürgen Ruf Thomas Kropf Wolfgang Rosenstiel 《Electronic Notes in Theoretical Computer Science》2006,135(2):47
In this paper we describe an algorithm for distributed, BDD-based bounded property checking and its implementation in the verification tool SymC. The distributed algorithm verifies larger models and returns results faster than the sequential version.The core algorithm distributes partitions of the state set to computation nodes after reaching a threshold size. The nodes proceed with image computation on the nodes asynchronously. The main scalability problem of this scheme is the overlap of state set partitions. We present static and dynamic overlap reduction techniques. 相似文献
85.
86.
87.
The absorption, metabolism, and excretion of lanatoside C were studied in hospitalized subjects following oral administration of the tritiated drug. Previous reports of an unusual double peak in plasma levels of radioactivity were confirmed. Fifty plasma samples taken from 31 patients showed that an average of 74% of the radioactive material was digoxin and its metabolites. There was little or no lanatoside C in 36 of the 50 samples of plasma. Similar results were obtained for urine radioactivity. The results confirm that lanatoside C is converted to "digoxin" in the gut prior to absorption as previously proposed by us. "Digoxin" refers to digoxin and its breakdown products, namely, digoxigenin and its mono- and didigitoxosides. According to these proposals, the conversion to "digoxin" takes place partly as a result of acid hydrolysis in the gut and partly by the action of bacteria in the intestine. The effects of concurrent administration of antacid therapy, anticholinergic therapy, and food on the fate of oral lanatoside C were separately studied. There were no significant differences between groups with respect to the amount of radioactive material absorbed or excreted, but there were marked qualitative differences in the plasma profiles. There was a statistically significant increase in the time to the first peak in plasma radioactivity in patients concurrently receiving either food or anticholinergic therapy and there was a significant decrease in the relative height of the first peak in patients treated concurrently with antacid. 相似文献
88.
Thomas H. Alden 《Metallurgical and Materials Transactions A》1977,8(11):1675-1679
According to the theory of thermally-activated deformation, the plastic strain rate equality
will hold in a load relaxation experiment, wheret = 0 is de-fined as the time at which the crosshead stops. In this theory, plastic flow is intrinsically time dependent and
its rate is controlled by interaction of glide dislocations with thermal obstacles(e.g. forest dislocations). The strain rate equation is of the form
and att = 0 none of these variables changes instantaneously. Measurements reported here for [111] aluminum single crystals indicate
that this prediction is wrong. The ratio
is near zero at low stress and approaches unity only at high stress. This result is predicted if plastic strain itself is
time-independent (athermal), as in the author’s recent theory. Time-dependent strain is then the result of thermal changes
in structure, namely loss (recovery) and rearrangement of obstacle dislocations. Experi-ments were also done to test further
the essential hypothesis of Hart’s recent formula-tion of an equation of state for plastic deformation-namely that each distinct
σ-@#@
curve derived from load relaxation data corresponds to a unique “hardness” state and that re-covery does not occur. Significant
differences were observed in the 77 K strsss-strain curves for 295 K relaxed and unrelaxed samples which indicate that substantial
loss and some rearrangement of dislocations has occurred during the relaxation. It is concluded from both experiments that
load relaxation in aluminum is a manifestation of recovery creep and cannot be taken as evidence for a plastic equation of
state. 相似文献
89.
Thomas P. L. Roellig James R. Houck 《Journal of Infrared, Millimeter and Terahertz Waves》1983,4(3):299-309
A new, 1-mm-continuum, bolometer detector system has been constructed employing internal adsorption pumping of He-3 to reach an operating temperature close to 0.4 K. The system spectral bandwidth is 800 to 1200 μm. Although the system was originally designed to be used on the 5-m Hale telescope, it has also been successfully used on the 4-m Anglo-Australian telescope and on the 10-m dish at Owens Valley, California. At the 5-m Hale telescope, the system has a full width-half maximum (FWHM) beam size of 55t" and an instantaneous noise-equivalent flux density of 6 \({{Jy} \mathord{\left/ {\vphantom {{Jy} {\sqrt {Hz} }}} \right. \kern-0em} {\sqrt {Hz} }}\) in good weather. 相似文献
90.
The design of two custom sample holders with a spherical cavity for commercial vibrating sample magnetometer systems is described. For such cavities, the magnetization M[over ->] and the internal magnetic field H(i)[over ->] of a sample are both homogeneous. Consequently, the material parameter M(H(i)) of a sample can be determined even for liquids and powders with a high magnetic susceptibility. 相似文献