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991.
The Web has evolved into a dominant digital medium for conducting many types of online transactions such as shopping, paying
bills, making travel plans, etc. Such transactions typically involve a number of steps spanning several Web pages. For sighted
users these steps are relatively straightforward to do with graphical Web browsers. But they pose tremendous challenges for
visually impaired individuals. This is because screen readers, the dominant assistive technology used by visually impaired
users, function by speaking out the screen’s content serially. Consequently, using them for conducting transactions can cause
considerable information overload. But usually one needs to browse only a small fragment of a Web page to do a step of a transaction
(e.g., choosing an item from a search results list). Based on this observation this paper presents a model-directed transaction
framework to identify, extract and aurally render only the “relevant” page fragments in each step of a transaction. The framework
uses a process model to encode the state of the transaction and a concept model to identify the page fragments relevant for
the transaction in that state. We also present algorithms to mine such models from click stream data generated by transactions
and experimental evidence of the practical effectiveness of our models in improving user experience when conducting online
transactions with non-visual modalities. 相似文献
992.
993.
SimRank has become an important similarity measure to rank web documents based on a graph model on hyperlinks. The existing
approaches for conducting SimRank computation adopt an iteration paradigm. The most efficient deterministic technique yields
O(n3)O\left(n^3\right) worst-case time per iteration with the space requirement O(n2)O\left(n^2\right), where n is the number of nodes (web documents). In this paper, we propose novel optimization techniques such that each iteration
takes O (min{ n ·m , nr })O \left(\min \left\{ n \cdot m , n^r \right\}\right) time and O ( n + m )O \left( n + m \right) space, where m is the number of edges in a web-graph model and r ≤ log2 7. In addition, we extend the similarity transition matrix to prevent random surfers getting stuck, and devise a pruning
technique to eliminate impractical similarities for each iteration. Moreover, we also develop a reordering technique combined
with an over-relaxation method, not only speeding up the convergence rate of the existing techniques, but achieving I/O efficiency
as well. We conduct extensive experiments on both synthetic and real data sets to demonstrate the efficiency and effectiveness
of our iteration techniques. 相似文献
994.
Underwater vehicle-manipulator systems (UVMS) are expected to play an important role in ocean exploration. It is considered
that UVMS will be operated by both automatic and manual control. We have proposed an automatic control method. In this article,
we propose a master-slave system for a UVMS. The effectiveness of the proposed master-slave control system is demonstrated
by using a floating underwater robot with a 2-link manipulator. 相似文献
995.
Ogier Maitre Frédéric Krüger Stéphane Querry Nicolas Lachiche Pierre Collet 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(2):261-279
EASEA is a framework designed to help non-expert programmers to optimize their problems by evolutionary computation. It allows
to generate code targeted for standard CPU architectures, GPGPU-equipped machines as well as distributed memory clusters.
In this paper, EASEA is presented by its underlying algorithms and by some example problems. Achievable speedups are also
shown onto different NVIDIA GPGPUs cards for different optimization algorithm families. 相似文献
996.
Wei-Lan Suo Bo Feng Zhi-Ping Fan 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(3):471-483
The decision making trial and evaluation laboratory (DEMATEL) method is a useful tool for analyzing correlations among factors
using crisp values. However, the crisp values are inadequate to model real-life situations due to the fuzziness and uncertainty
that are frequently involved in judgments of experts. The aim of this paper is to extend the DEMATEL method to an uncertain
linguistic environment. In this paper, the correlation information among factors provided by experts is in the form of uncertain
linguistic terms. A formula is first presented to transform correlation information from uncertain linguistic terms to trapezoidal
fuzzy numbers. Then, we aggregate the transformed correlation information of each expert into group information using the
operations of trapezoidal fuzzy numbers. The importance and classification of factors are determined via fuzzy matrix operations.
Furthermore, a causal diagram is constructed to vividly show the different roles of factors. Finally, an example is used to
illustrate the procedure of the proposed method. 相似文献
997.
In this paper, we propose a multi-agent learning system for the control of an intelligent robot, based on a model of the human
consciousnesses, including the ego. We pay attention to the intelligent learning processes of human beings. We try to give
a robot a high learning ability by modeling the roles of the human consciousnesses, including the ego. In most ordinary methods,
the instructions for learning are given from outside the system only. In the proposed method, the instructions are given not
only from outside, but also from inside (from other agents in the system). Therefore, the robot can learn efficiently because
it has more instructions than usual. The learning is also more flexible, since an agent learns by instructions from other
agents while the learning agent and one of the instructing agents exchange roles according to changes in the environment.
We experimentally verified that the proposed method is efficient by using an actual robot. 相似文献
998.
999.
Tae Hyon Kim Kiyohiro Goto Hiroki Igarashi Kazuyuki Kon Noritaka Sato Fumitoshi Matsuno 《Artificial Life and Robotics》2012,16(4):514-518
Recently, many research projects and competitions have attempted to find an autonomous mobile robot that can drive in the
real world. In this article, we consider a path-planning method for an autonomous mobile robot that would be safe in a real
environment. In such a case, it is very important for the robot to be able to identify its own position and orientation in
real time. Therefore, we applied a localization method based on a particle filter. Moreover, in order to improve the safety
of such autonomous locomotion, we improved the path-planning algorithm and the generation of the trajectory so that it can
consider a region with a limited maximum velocity. In order to demonstrate the validity of the proposed method, we participated
in the Real World Robot Challenge 2010. The experimental results are given. 相似文献
1000.
Ekrem Savaş 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(4):591-595
Quite recently, Sava? (Appl Math Lett 21:134–141, 2008), defined the lacunary statistical analogue for double sequence \(X=\{X_{k,l}\}\) of fuzzy numbers as follows: a double sequence \(X=\{X_{k,l}\}\) is said to be lacunary P-statistically convergent to \(X_{0}\) provided that for each \(\epsilon >0\) In this paper we introduce and study double lacunary \(\sigma\)-statistical convergence for sequence of fuzzy numbers and also we get some inclusion theorems.
相似文献
$ P-\lim_{r,s}\frac{1}{h_{r,s}}\left | \{(k,l)\in I_{r,s}: d(X_{k,l },X_0)\geq \epsilon\}\right|= 0. $