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81.
In this paper we study a class of CQ Horn functions introduced in Boros et al. (Ann Math Artif Intell 57(3–4):249–291, 2010). We prove that given a CQ Horn function f, the maximal number of pairwise disjoint essential sets of implicates of f equals the minimum number of clauses in a CNF representing f. In other words, we prove that the maximum number of pairwise disjoint essential sets of implicates of f constitutes a tight lower bound on the size (the number of clauses) of any CNF representation of f. 相似文献
82.
When programmers need to modify third‐party applications, they frequently do not have access to their source code. In such cases, DLL injection and API hooking are techniques that can be used to modify applications without intervening into their source code. The commonly used varieties of injection and hooking approaches have many practical limitations: they are inconvenient for a programmer to implement, do not work reliably in conjunction with all applications and with certain low‐level machine instructions. In this paper we present two novel approaches to DLL injection and API hooking, which we call Debugger‐aided DLL injection and Single Instruction Hooking. Our approaches overcome the limitations of the state‐of‐the art approaches. Despite incurring greater execution times, our approach allows extending of the applications in situations where the comparable approaches fail. As such, it has a notable practical value for beneficial practical applications of injection and hooking approaches, which are present in malware detection programs and computer security tools. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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84.
Petra Punčochářová-Pořízková Jiří Fürst Jaromír Horáček Karel Kozel 《Mathematics and computers in simulation》2010
This study deals with a numerical solution of a 2D unsteady flow of a compressible viscous fluid in a channel for low inlet airflow velocity. The unsteadiness of the flow is caused by a prescribed periodic motion of a part of the channel wall with large amplitudes, nearly closing the channel during oscillations. The channel is a simplified model of the glottal space in the human vocal tract and the flow can represent a model of airflow coming from the trachea, through the glottal region with periodically vibrating vocal folds, and to the human vocal tract. 相似文献
85.
86.
Urban environments possess many regularities which can be efficiently exploited for 3D dense reconstruction from multiple
widely separated views. We present an approach utilizing properties of piecewise planarity and restricted number of plane
orientations to suppress reconstruction and matching ambiguities causing failures of standard dense stereo methods. We formulate
the problem of the 3D reconstruction in MRF framework built on an image pre-segmented into superpixels. Using this representation,
we propose novel photometric and superpixel boundary consistency terms explicitly derived from superpixels and show that they
overcome many difficulties of standard pixel-based formulations and handle favorably problematic scenarios containing many
repetitive structures and no or low textured regions. We demonstrate our approach on several wide-baseline scenes demonstrating
superior performance compared to previously proposed methods. 相似文献
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89.
N. Lilić I. Obradović A. Cvjetić 《Engineering Applications of Artificial Intelligence》2010,23(4):453-462
Analysis of safety in surface coal mines represents a very complex process. Published studies on mine safety analysis are usually based on research related to accidents statistics and hazard identification with risk assessment within the mining industry. Discussion in this paper is focused on the application of AI methods in the analysis of safety in mining environment. Complexity of the subject matter requires a high level of expert knowledge and great experience. The solution was found in the creation of a hybrid system PROTECTOR, whose knowledge base represents a formalization of the expert knowledge in the mine safety field. The main goal of the system is the estimation of mining environment as one of the significant components of general safety state in a mine. This global goal is subdivided into a hierarchical structure of subgoals where each subgoal can be viewed as the estimation of a set of parameters (gas, dust, climate, noise, vibration, illumination, geotechnical hazard) which determine the general mine safety state and category of hazard in mining environment. Both the hybrid nature of the system and the possibilities it offers are illustrated through a case study using field data related to an existing Serbian surface coal mine. 相似文献
90.
We investigated intrinsic noise in plasmonic sensors caused by adsorption and desorption of gaseous analytes on the sensor
surface. We analyzed a general situation when there is a larger number of different analyte species. We applied our model
to calculate various analyte mixtures, including some environmental pollutants, toxic and dangerous substances. The spectral
density of mean square refractive index fluctuations follows a dependence similar to that of generation-recombination noise
in photodetectors, flat at lower frequencies and sharply decreasing at higher. Some of the calculated noise levels are well
within the detection range of conventional surface plasmon resonance sensors. An AD noise peak is observed in temperature
dependence of mean square refractive index fluctuations, thus sensor operating temperature may be optimized to obtain larger
signal to noise ratio. A significant property of AD noise is its rise with the decreasing plasmon sensor area, which means
that it will be even more pronounced in modern nanoplasmonic devices. Our consideration is valid both for conventional surface
plasmon resonance devices and for general nanoplasmonic devices. 相似文献