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171.
172.
R. Chavan G. Chitarin R.S. Delogu A. Encheva A. Gallo E.R. Hodgson L.C. Ingesson A. Le-Luyer J.B. Lister Ph. Moreau J.-M. Moret S. Peruzzo J. Roméro D.S. Testa M. Toussaint G. Vayakis R. Vila 《Fusion Engineering and Design》2009,84(2-6):295-299
The current status of the ITER magnetics diagnostic is summarised. The various risks are discussed on the basis of when they could be present during ITER operation and appropriate mitigation is reviewed. An implementation risk or common mode operation failure risk to the magnetic diagnostic can only be mitigated by diversity. All identified risks are being handled with ongoing research and development to minimise these risks. A reasonable level of design and manufacturing diversity has been therefore introduced in the procurement and installation plans, in order to optimise overall reliability avoiding dispersion of resources. 相似文献
173.
Observers can recognize other people from their movements. What is interesting is that observers are best able to recognize their own movements. Enhanced visual sensitivity to self-generated movement may reflect the contribution of motor planning processes to the visual analysis of human action. An alternative view is that enhanced visual sensitivity to self-motion results from extensive experience seeing one's own limbs move. To investigate this alternative explanation, participants viewed point-light actors from first-person egocentric and third-person allocentric viewpoints. Although observers routinely see their own actions from the first-person view, participants were unable to identify egocentric views of their own actions. Conversely, with little real-world experience seeing themselves from third-person views, participants readily identified their own actions from allocentric views. When viewing allocentric displays, participants accurately identified both front and rear views of their own actions. Because people have little experience observing themselves from behind or from third-person views, these findings suggest that visual learning cannot account for enhanced visual sensitivity to self-generated action. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
174.
Dinesh Prasad D. R. Bhaskar A. K. Singh 《Analog Integrated Circuits and Signal Processing》2009,61(3):309-313
An universal multi input single output type multifunction biquad is proposed. The proposed configuration employs only one
current differencing transconductance amplifier as the active element, two capacitors and three resistors. The circuit realizes
all five filter functions (i.e. Low Pass, High Pass, Band Pass, Notch and All Pass) without changing the circuit topology.
The natural frequency ω0 is independently and electronically tunable. The workability of the proposed multifunction biquad has been verified using
SPICE simulation. 相似文献
175.
Gayatri Prasad Kamalesh Prasad Ramavatar Meena A. K. Siddhanta 《Journal of Materials Science》2009,44(15):4062-4068
A hybrid material was prepared from the hot water soluble sulphated polysaccharide of the green seaweed Chaetomorpha antennina (CMsps) and polymethyl methacrylate (PMMA) by radical polymerization in aqueous medium under microwave irradiation. An insoluble
material was formed with the progress of the polymerization. The product was characterized by the IR spectrum and elemental
analysis, as well as by acid hydrolysis followed by mass spectrum of the hydrolysate of the hybrid CMsps–PMMA for confirming the insertion of PMMA. Comprehensive characterization of the product included TGA, XRD, ESI-MS and BET
surface analysis. The hybrid material was porous, and formed gel in water–DMSO mixture. It had the crystallinity index of
0.122, and had BET pore diameter of 3.71 nm, a size which is far larger than the molecular diameters of common natural gases
and zeolites (0.5–1.0 nm). This material may be useful in the domain of certain adsorption and catalytic applications. 相似文献
176.
Durga Prasad Muni Nikhil R Pal Jyotirmoy Das 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(1):106-117
This paper presents an online feature selection algorithm using genetic programming (GP). The proposed GP methodology simultaneously selects a good subset of features and constructs a classifier using the selected features. For a c-class problem, it provides a classifier having c trees. In this context, we introduce two new crossover operations to suit the feature selection process. As a byproduct, our algorithm produces a feature ranking scheme. We tested our method on several data sets having dimensions varying from 4 to 7129. We compared the performance of our method with results available in the literature and found that the proposed method produces consistently good results. To demonstrate the robustness of the scheme, we studied its effectiveness on data sets with known (synthetically added) redundant/bad features. 相似文献
177.
Arvind Prasad Hani Nenein Kelly Conlon 《Metallurgical and Materials Transactions A》2006,37(5):1589-1596
A new technique is introduced to quantify microsegregation during rapid solidification. The quantification involves calculation
of the average solute solubility in the primary phase during solidification of an Al-Cu binary alloy. The calculation is based
on using volume percent eutectic and weight percent of second phase (in the eutectic), which were obtained experimentally.
Neutron diffraction experiments and stereology calculation on scanning electron microscope images were done on impulse atomized
Al-Cu alloys of three compositions (nominal), 5 wt pct Cu, 10 wt pct Cu, and 17 wt pct Cu, atomized under N2 and He gas. Neutron diffraction experiments yielded weight percent CuAl2 data and stereology yielded volume percent eutectic data. These two data were first used to determine the weight percent
eutectic. Using the weight percent eutectic and weight percent CuAl2 in mass and volume balance equations, the average solute solubility in the primary phase could be calculated. The experimental
results of the amount of eutectic, tomography results from previous work, and results from the calculations suggest that the
atomized droplets are in metastable state during the nucleation undercooling of the primary phase, and the effect of metastability
propagates through to the eutectic formation stage. The metastable effect is more pronounced in alloys with higher solute
composition. 相似文献
178.
Anand R. Prasad 《Wireless Personal Communications》2006,37(3-4):187-211
The future of telecommunications is to reach mass population in all regions of the world with services that will benefit humankind leading to the betterment of its and all life in our planet. Telecommunications and its services have to and will become part of life as is breathing to mankind. This future is by far not achieved and for some time to come whatever we develop there is always a next step to it. After all, that keeps our world going.Currently we are again at that stage of work on future generation communications where these words have not yet achieved a consensus. In this paper let us look at the crystal ball and try to materialize at least in words what we see in it [1–20].We first define fourth generation (4G) communication system and beyond 3G (B3G). Then we look at the requirements for future generation communications from the perspective of the users, the operators, and the service providers. Next the technologies that should and are being developed to materialize the future generation are discussed. A dip is also taken into the ongoing standardization or pre-standardization efforts. At first the introduction section tries to raise questions on the “future”.Prof. Dr. Ramjee Prasad, while being a father always there for his children, is also a visionary and a leader in the field of telecommunications. It is with pride and honour that I write in this paper, on the occasion of 60th birthday of my father, my thoughts of the future of telecommunications. I owe to him and my mother the knowledge that I present and the future that I have written of. It is from the spark that they had put in me that this vision of future was created thus the title “the future re-visited”. Disclaimer: This paper reflects opinion of the author not of NTT DoCoMo or DoCoMo Euro-Labs.
Anand Raghawa Prasad Senior Member IEEE, project manager network level security model group, DoCoMo Euro-Labs, Munich, Germany was born in Ranchi, India. He received his Ph.D. degree in the field of WLANs: protocols, security and deployment and MSc (Ir.) degree in the field of Self Similarity in ATM Network Traffic from Delft University of Technology, The Netherlands, in 2003 and 1996, respectively. From 1996 to 1998 he worked as research engineer and later project leader in Uniden Corporation, Tokyo, Japan. From 1998 to 2000, he was distinguished member of technical staff and worked as systems architect for IEEE 802.11 based WLANs (WaveLAN and ORiNOCO) in Lucent Technologies, Nieuwegein, The Netherlands. Subsequently, he was technical director at Genista Corporation, Tokyo, Japan, and technical advisor of PCOM:I3, Aalborg, Denmark. He was a voting member of IEEE 802.11 and he is an active participant of 3GPP. In addition to his publications in journals, international conferences and chapters in books, he has 20$+$ patent applications in the field of wireless communications and has co-edited a book titled “WLAN Systems and Wireless IP for Next Generation Communications” and co-authored a book on “Wireless LANs and Wireless IP: Security, Mobility, QoS and Mobile Network Integration” both published by Artech House in 2002 and 2005 respectively. He is writing a book on “Security in Wireless Networks and Mobile Platforms” to be published in August 2006. He has participated in organizing of various International Conferences including VTC, PIMRC and WPMC. He was a guest editor of a special issue on “Security for Next Generation Communications” of the Springer Journal on Wireless Personal Communications and he is a guest editor of a special issue on “Seamless Handover in Next Generation Wireless/Mobile Communications” of Wireless Personal Communications. 相似文献
179.
180.
D. G. Kuberkar N. A. Shah M. R. Gonal R. Prasad R. G. Kulkarni 《Journal of Superconductivity》2000,13(1):37-40
It has been reported that, by adding equal amounts of CaO and CuO to non superconducting La3Ba3Cu6O
z
(La-336), a series of superconductors with nominal compositions La3Ca
y
Ba3Cu6+y
O
z
were prepared with maximum Ton
c 80K. Similar studies on addition of CaO and CuO in nonsuperconducting LaBaCu2O
z
(La-112) resulted into superconducting LaCaBaCu3O
z
(La-1113). To date no attempt has been made to synthesize La2CaBa2Cu5O
z
(La-2125) superconducting phase by addition of CaO and CuO to non superconducting La2Ba2Cu4O
z
(La-224) system. Also no reports are published to study the effect of replacing larger La3+-ions (1.01Å) by smaller rare earth ions viz Y3+(0.89Å), Er3+(0.91Å), Gd3+(0.91Å) on the structural and superconducting properties of (La2–x
R
x
)Ba2(Ca
y
Cu4+y
)O
z
(LRBCaC); 0.0 x 0.5; y=2x system. In this paper, we report the method of synthesis, structural and superconducting property characterization using X-ray diffraction, oxygen content measurements using iodometry, resistivity measurements using d.c. four probe technique and a.c. susceptibility measurements in the temperature range RT to 15K. Also a comparative study, on the evolution of superconducting phase with Ca-concentration for different rare earth substitutions for LRBCaC system in the context of hole doping mechanism, is carried out. 相似文献