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61.
A density-based partitioning strategy is proposed for large domain networks in order to deal with the scalability issue found in autonomic networks considering, as a scenario, the autonomic Quality of Service (QoS) management context. The approach adopted focus as on obtaining dense network partitions having more paths for a given vertices set in the domain. It is demonstrated that dense partitions improve autonomic processing scalability, for instance, reducing routing process complexity. The solution looks for a significant trade-off between partition autonomic algorithm execution time and path selection quality in large domains. Simulation scenarios for path selection execution time are presented and discussed. Authors argue that autonomic networks may benefit from the dense partition approach proposed by achieving scalable, efficient and near real-time support for autonomic management systems. 相似文献
62.
63.
Pflieger D Gonnet F de la Fuente van Bentem S Hirt H de la Fuente A 《Mass spectrometry reviews》2011,30(2):268-297
Proteomes are intricate. Typically, thousands of proteins interact through physical association and post-translational modifications (PTMs) to give rise to the emergent functions of cells. Understanding these functions requires one to study proteomes as "systems" rather than collections of individual protein molecules. The abstraction of the interacting proteome to "protein networks" has recently gained much attention, as networks are effective representations, that lose specific molecular details, but provide the ability to see the proteome as a whole. Mostly two aspects of the proteome have been represented by network models: proteome-wide physical protein-protein-binding interactions organized into Protein Interaction Networks (PINs), and proteome-wide PTM relations organized into Protein Signaling Networks (PSNs). Mass spectrometry (MS) techniques have been shown to be essential to reveal both of these aspects on a proteome-wide scale. Techniques such as affinity purification followed by MS have been used to elucidate protein-protein interactions, and MS-based quantitative phosphoproteomics is critical to understand the structure and dynamics of signaling through the proteome. We here review the current state-of-the-art MS-based analytical pipelines for the purpose to characterize proteome-scale networks. 相似文献
64.
M. J. Annen R. Kizhappali P. W. Carr A. McCormick 《Journal of Materials Science》1994,29(23):6123-6130
Polymerization-induced colloid aggregation is used to synthesize spheres of narrow size distribution which are porous aggregates of ZrO2 colloids. Variation of the reaction pH has been investigated to determine the optimum rate of polymerization of the urea-formaldehyde resin. At the optimum rate, a colloid packing structure is formed where a balance of high porosity and high strength of the aggregates is achieved. This optimum coincides with the maximum yield of the 5 m sintered (polymer-free) particles. Particles synthesized at pH values below the optimum are mechanically weak; some are hollow spheres. Variation of the pore structure, and thus colloid packing structure, is elucidated by nitrogen adsorption and apparent density measurements. Differences on either side of the optimum pH are related to the efficiency of polymer-bridge formation between colloids. 相似文献
65.
66.
Marialucia Gallorini Viviana di Giacomo Valentina Di Valerio Monica Rapino Domenico Bosco Andrea Travan Mara Di Giulio Roberta Di Pietro Sergio Paoletti Amelia Cataldi Silvia Sancilio 《Journal of materials science. Materials in medicine》2016,27(12):186
Silver-based products have been proven to be effective in retarding and preventing bacterial growth since ancient times. In the field of restorative dentistry, the use of silver ions/nanoparticles has been explored to counteract bacterial infections, as silver can destroy bacterial cell walls by reacting with membrane proteins. However, it is also cytotoxic towards eukaryotic cells, which are capable of internalizing nanoparticles. In this work, we investigated the biological effects of Chitlac-nAg, a colloidal system based on a modified chitosan (Chitlac), administered for 24–48?h to a co-culture of primary human gingival fibroblasts and Streptococcus mitis in the presence of saliva, developed to mimic the microenvironment of the oral cavity. We sought to determine its efficiency to combat oral hygiene-related diseases without affecting eukaryotic cells. Cytotoxicity, reactive oxygen species production, apoptosis induction, nanoparticles uptake, and lysosome and autophagosome metabolism were evaluated. In vitro results show that Chitlac-nAg does not exert cytotoxic effects on human gingival fibroblasts, which seem to survive through a homoeostasis mechanism involving autophagy. That suggests that the novel biomaterial Chitlac-nAg could be a promising tool in the field of dentistry. 相似文献
67.
Exploring the power of shared memory communication objects and models, and the limits of distributed computability are among the most exciting research areas of distributed computing. In that spirit, this paper focuses on a problem that has received considerable interest since its introduction in 1987, namely the renaming problem. It was the first non-trivial problem known to be solvable in an asynchronous distributed system despite process failures. Many algorithms for renaming and variants of renaming have been proposed, and sophisticated lower bounds have been proved, that have been a source of new ideas of general interest to distributed computing. It has consequently acquired a paradigm status in distributed fault-tolerant computing.In the renaming problem, processes start with unique initial names taken from a large name space, then deciding new names such that no two processes decide the same new name and the new names are from a name space that is as small as possible.This paper presents an introduction to the renaming problem in shared memory systems, for non-expert readers. It describes both algorithms and lower bounds. Also, it discusses strong connections relating renaming and other important distributed problems such as set agreement and symmetry breaking. 相似文献
68.
Sergio S��nchez Garc��a Ana G��mez Oliva Emilia P��rez Belleboni Iv��n Pau de la Cruz 《International Journal of Information Security》2011,10(6):351-372
At present, many countries allow citizens or entities to interact with the government outside the telematic environment through
a legal representative who is granted powers of representation. However, if the interaction takes place through the Internet,
only primitive mechanisms of representation are available, and these are mainly based on non-dynamic offline processes that
do not enable quick and easy identity delegation. This paper proposes a system of dynamic delegation of identity between two
generic entities that can solve the problem of delegated access to the telematic services provided by public authorities.
The solution herein is based on the generation of a delegation token created from a proxy certificate that allows the delegating
entity to delegate identity to another on the basis of a subset of its attributes as delegator, while also establishing in
the delegation token itself restrictions on the services accessible to the delegated entity and the validity period of delegation.
Further, the paper presents the mechanisms needed to either revoke a delegation token or to check whether a delegation token
has been revoked. Implications for theory and practice and suggestions for future research are discussed. 相似文献
69.
Privacy in geo-social networks: proximity notification with untrusted service providers and curious buddies 总被引:2,自引:0,他引:2
Sergio Mascetti Dario Freni Claudio Bettini X. Sean Wang Sushil Jajodia 《The VLDB Journal The International Journal on Very Large Data Bases》2011,20(4):541-566
A major feature of the emerging geo-social networks is the ability to notify a user when any of his friends (also called buddies)
happens to be geographically in proximity. This proximity service is usually offered by the network itself or by a third party service provider (SP) using location data acquired from the
users. This paper provides a rigorous theoretical and experimental analysis of the existing solutions for the location privacy
problem in proximity services. This is a serious problem for users who do not trust the SP to handle their location data and
would only like to release their location information in a generalized form to participating buddies. The paper presents two
new protocols providing complete privacy with respect to the SP and controllable privacy with respect to the buddies. The
analytical and experimental analysis of the protocols takes into account privacy, service precision, and computation and communication
costs, showing the superiority of the new protocols compared to those appeared in the literature to date. The proposed protocols
have also been tested in a full system implementation of the proximity service. 相似文献
70.
A non-intrusive estimation for high-quality Internet TV services 总被引:1,自引:0,他引:1
Alberto?Fraga Laura?Pozueco Xabiel?Garcia Pa?edaEmail author Roberto?García David?Melendi Sergio?Cabrero 《Multimedia Tools and Applications》2011,54(3):569-588
This paper presents a non-intrusive estimator for Internet TV services based on streaming technology. Analyzing the video
packets received by the client application, the estimator is capable of selecting the most suitable encoding bitrate for the
available bandwidth in the end-to-end path. The estimator has been integrated in a real client/server architecture and evaluated
with different network traffic situations. The results of the performed evaluation have revealed the stability and adaptation
speed as the best qualities of our proposal. 相似文献