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排序方式: 共有5057条查询结果,搜索用时 343 毫秒
51.
James Mammen Devavrat Shah 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(3):1108-1116
Grossglauser and Tse (2001) introduced a mobile random network model where each node moves independently on a unit disk according to a stationary uniform distribution and showed that a throughput of Theta(1) is achievable. El Gamal, Mammen, Prabhakar, and Shah (2004) showed that the delay associated with this throughput scales as Theta(nlogn), when each node moves according to an independent random walk. In a later work, Diggavi, Grossglauser, and Tse (2002) considered a random network on a sphere with a restricted mobility model, where each node moves along a randomly chosen great circle on the unit sphere. They showed that even with this one-dimensional restriction on mobility, constant throughput scaling is achievable. Thus, this particular mobility restriction does not affect the throughput scaling. This raises the question whether this mobility restriction affects the delay scaling. This correspondence studies the delay scaling at Theta(1) throughput for a random network with restricted mobility. First, a variant of the scheme presented by Diggavi, Grossglauser, and Tse (2002) is presented and it is shown to achieve Theta(1) throughput using different (and perhaps simpler) techniques. The exact order of delay scaling for this scheme is determined, somewhat surprisingly, to be of Theta(nlogn), which is the same as that without the mobility restriction. Thus, this particular mobility restriction does not affect either the maximal throughput scaling or the corresponding delay scaling of the network. This happens because under this 1-D restriction, each node is in the proximity of every other node in essentially the same manner as without this restriction 相似文献
52.
Mardia K.V. Wei Qian Shah D. de Souza K.M.A. 《IEEE transactions on pattern analysis and machine intelligence》1997,19(9):1035-1042
Based on deformable templates, the paper formulates an integrated and flexible Bayesian recognition system of multiple occluded objects. Various local dependence properties of the model are obtained to reduce the computational cost with the increase in the number of objects. Numerical results for a synthetic image and for a real image of mushrooms are discussed 相似文献
53.
Eskildsen L. Goldstein E.L. Andrejco M. Curtis L. Shah V. Mahoney D. Zah C.E. Lin C. 《Electronics letters》1993,29(23):2040-2041
Phase-induced intensity noise from weak multiple reflectors is evaluated theoretically and experimentally in amplifier cascades without isolators. Rayleigh backscattering alone significantly limits the number of amplifiers in the span. Theory and experiment agree closely for a six-amplifier cascade.<> 相似文献
54.
JL Shah 《Canadian Metallurgical Quarterly》1998,53(10):1032-1033
55.
We examined the effect of meprin A, the major matrix degrading metalloproteinase in rat kidney, on the laminin-nidogen complex. N-terminal sequence information from the most abundant 55 kDa fragment revealed that it was a breakdown product of nidogen rather than laminin. In comparison with over 50 nidogen cleavage sites produced by other proteases, the meprin A-induced nidogen cleavage site at amino acid position 899-900, a glutamine-glycine site in the G3 domain, is unique. In addition, these data demonstrate that meprin A degrades the G3 domain of nidogen even in the presence of laminin binding, which usually accords protection from proteolytic degradation. Meprin A also degraded purified nidogen into similar breakdown products. Given that the tubular basement membrane is located on the basilar side of the cell, the location of meprin A on the apical brush border makes it difficult to envision a role for meprin A in injury-induced basement membrane component breakdown. Thus, we examined the possibility that following renal tubular epithelial cell injury, meprin A undergoes a translocation to reach the underlying basement membrane. After renal ischemia-reperfusion there was a marked alteration in meprin A staining with meprin A now distributed throughout the renal tubular cell cytoplasm and directly adherent to the tubular basement membrane. This was in contrast to the usual linear staining of the brush border of tubules in the corticomedullary junction. These data provide unequivocal evidence that following injury, meprin A undergoes redistribution and/or adherence to the tubular basement membrane. Since in our in vitro studies, we identified a distinct meprin-induced 55 kDa nidogen breakdown product, the urine was also examined for the presence of nidogen degradation products after rat renal ischemia-reperfusion injury. Western blots showed a marked increase in the urinary 55 kDa nidogen fragment as early as the first day following ischemia-reperfusion injury and continuing for six days. Taken together, these in vivo data strongly support the notion that the nidogen breakdown products are the result of partial degradation of tubular basement membrane by meprin A following renal tubular ischemia-reperfusion injury. 相似文献
56.
SJ Simpson S Shah M Comiskey YP de Jong B Wang E Mizoguchi AK Bhan C Terhorst 《Canadian Metallurgical Quarterly》1998,187(8):1225-1234
57.
Touqeer Haseeb Zaman Shakir Amin Rashid Hussain Mudassar Al-Turjman Fadi Bilal Muhammad 《The Journal of supercomputing》2021,77(12):14053-14089
The Journal of Supercomputing - The Internet of Things is a rapidly evolving technology in which interconnected computing devices and sensors share data over the network to decipher different... 相似文献
58.
Khan Muhammad Hussain Saleem Zainab Ahmad Muhammad Sohaib Ahmed Ayaz Hamail Mazzara Manuel Raza Rana Aamir 《Neural computing & applications》2021,33(21):14507-14521
Neural Computing and Applications - Preserving red-chili quality is of utmost importance in which the authorities demand quality techniques to detect, classify, and prevent it from impurities. For... 相似文献
59.
One of the important aspects in achieving better performance for transient stability assessment (TSA) of power systems employing
computational intelligence (CI) techniques is by incorporating feature reduction techniques. For small power system the number
of features may be small but when larger systems are considered the number of features increased as the size of the systems
increases. Apart from employing faster CI techniques to achieve faster and accurate TSA of power system, feature reduction
techniques are needed in reducing the input features while preserving the needed information so as to make faster training
of the CI technique. This paper presents feature reductions techniques used, namely correlation analysis and principle component
analysis, in reducing number of input features presented to two CI techniques for TSA, namely probabilistic neural network
(PNN) and least squares support vector machines (LS-SVM). The proposed feature reduction techniques are implemented and tested
on the IEEE 39-bus test system and 87-bus Malaysia’s power system. Numerical results are presented to demonstrate the performance
of the feature reduction techniques and its effects on the accuracies and time taken for training the two CI techniques. 相似文献
60.
Erik Cambria Marco Grassi Amir Hussain Catherine Havasi 《Multimedia Tools and Applications》2012,59(2):557-577
In a world in which millions of people express their opinions about commercial products in blogs, wikis, fora, chats and social networks, the distillation of knowledge from this huge amount of unstructured information can be a key factor for marketers who want to create an image or identity in the minds of their customers for their product, brand or organization. Opinion mining for product positioning, in fact, is getting a more and more popular research field but the extraction of useful information from social media is not a simple task. In this work we merge AI and Semantic Web techniques to extract, encode and represent this unstructured information. In particular, we use Sentic Computing, a multi-disciplinary approach to opinion mining and sentiment analysis, to semantically and affectively analyze text and encode results in a semantic aware format according to different web ontologies. Eventually we represent this information as an interconnected knowledge base which is browsable through a multi-faceted classification website. 相似文献