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991.
The quantum 1/f noise theory has been developed in the last two decades and has been applied to 1/f noise suppression in various electronic devices. This theory derives fundamental quantum fluctuations present in the elementary processes of physics at the level of the quantum mechanical cross sections and process rates. This paper demonstrates the basic simplicity of the theory with an elementary physical derivation followed by a short derivation of the conventional quantum 1/f effect in second quantization, for an arbitrary number of particles N defining the scattered current in the final state. A new derivation of the coherent quantum 1/f effect is also included. No adjustable parameters are present in the quantum 1/f theory. Practical applications to semiconductor materials, p-n junctions, SQUID's and quartz resonators are presented. Optimal design principles based on the quantum 1/f theory are described and explained 相似文献
992.
A new analytical model is described for the pentode-like region of the characteristics of recessed-gate SIT structures. The model allows one to investigate the transition from saturating characteristics of long channel JFET's to nonsaturating behavior of SIT devices, taking into account realistic device geometry 相似文献
993.
The device parameters of overgrown silicon permeable base transistors (PBT's) have been systematically investigated by two dimensional drift diffusion simulations and analytical calculations. Hence some design rules arise for optimizing the high frequency performance of PBT's. The calculations indicate the source-drain distance as the essential PBT parameter, which should be kept below 200 nm in order to expect unity-current-gain frequencies fT over 50 GHZ. In addition, PBT's with buried monocrystalline CoSi2-gates have been fabricated by high dose cobalt ion implantation through a grid-like mask into MOS-compatible n-type Si(100). Measurements revealed a transconductance of 70 mS/mm and a f T value of 6 GHz. The comparison between measured and simulated output characteristics shows good agreement 相似文献
994.
Bellens R. de Schrijver E. Van den Bosch G. Groeseneken G. Heremans P. Maes H.E. 《Electron Devices, IEEE Transactions on》1994,41(3):413-419
A continued fast interface trap generation is observed in n-channel MOS transistors after termination of the hot-carrier stress. The magnitude of this post-stress effect is strongly dependent on the conditions of the preceding stress, on the post-stress conditions and on the process parameters. For measurements at 293 K, a simple model is proposed which is based on the release of hydrogen by the thermal detrapping of holes, and which can explain the observed dependencies. The importance of the post-stress Dit-generation is illustrated for the case of dynamic stress conditions where it can lead to an apparently deviating degradation behavior 相似文献
995.
Matsuoka F. Kasai K. Oyamatsu H. Kinugawa M. Maeguchi K. 《Electron Devices, IEEE Transactions on》1994,41(3):420-426
A guideline for n- fully gate overlapped (FOLD) structure design optimization has been studied. From the viewpoint of reliability, the greatest reduction in substrate current directly leads to the most reliable n- design for the FOLD structure. The current path modulation phenomenon due to the trapped charge at the n - extension region dominates the hot-carrier induced characteristics change for conventional lightly doped drain (LDD) structure with side-wall spacer. This phenomenon is minimized in the FOLD structure due to its higher controllability of the gate electrode than the LDD structure at the n- extension region. Furthermore, it was also confirmed that the 0.3 μm optimized FOLD structure can achieve high circuit performance at 3.3 V operation, maintaining hot-carrier resistance 相似文献
996.
Lugosi G. Pawlak M. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1994,40(2):475-481
The posterior-probability estimate of the classification error rate of some nonparametric classification rules is studied. The variance of the estimator is shown to have same remarkable distribution-free properties for the k-nearest neighbor, kernel, and histogram rules. We also investigate the bias of the estimate and establish its consistency and upper bounds. The version of the estimate calculated from an independent set of unclassified patterns is also considered 相似文献
997.
This paper presents an overview of the ways in which self-esteem operates in employee communication. As they develop effective communication skills, managers need to consider the consequence of stress on employee self-esteem and performance. Persons with high self-esteem are less likely to experience workplace demands as stressful and are better able to respond effectively to those demands. This paper discusses the relationship among self-esteem, occupational stress, and communication quality, then recommends ways in which self-esteem can be enhanced through employee communication 相似文献
998.
There is a rising interest within the world community in what is occurring in professional communication in Russia, and in the social and market opportunities that will appear there in the future. We live in a world in which the pace of change is more rapid than at any time in our history. The most important aspect of this change is the fact that we are making a transition to a democratic society at the same time as we are in the process of establishing the principles of a market economy. Russia is a country with enormous reserves of raw materials, vast territories, and rich intellectual resources. And now, as Russia is experiencing a painful transition to a market economy, the nation's economic potential becomes more and more dependent on the sophistication of its infrastructure. That is the reason why the information technologies and professional communication have become key factors of social progress. The Russian centers of research and industry are widely dispersed geographically, in such cities as Vladivostok, Irkutsk, Novosibirsk, Tomsk, Ekaterinburg, Saint Petersburg and Moscow. The last three or four years have seen a sharp increase in the demands for business information, electronic mail and communications for far-flung business and financial operations 相似文献
999.
1000.
Tsong-Ho Wu Kobrinski H. Ghosal D. Lakshman T.V. 《Selected Areas in Communications, IEEE Journal on》1994,12(1):79-87
The viability of distributed control restoration using digital cross-connect systems (DCS) depends on its capability for restoring services within specified time requirements, and its economics for providing restoration compared to other alternatives. The authors report a Bellcore study for the impact of the DCS architecture on distributed restoration. This study concludes that currently proposed distributed control DCS self-healing schemes may not meet the 2 second restoration objective for large metropolitan local exchange carrier's networks, regardless of the distributed algorithm used, if the present DCS system architecture which uses serial message processing and serial path cross-connection remains unchanged. They also discuss several DCS architecture enhancement options, including a parallel processing/cross-connect DCS architecture, which may improve the service restoration time 相似文献