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951.
We present a toolbox that enables access to real robotics and automation (R&A) equipment from the MATLAB shell. If used in conjunction with a robotics toolbox, it will extend significantly their application, i.e., besides robotic simulation and data analysis, the user can interact online with the equipment he or she is using. This article briefly presents the software architecture adopted and how it was used to generate the MATLAB MEX files presented. It then exemplifies application to two types of equipment, complemented with a generic manipulation example using a robotic gripper. The utilization of this tool with force control experiments is also briefly explored 相似文献
952.
Jeon J.H. Kim H.S. Boo G.N. Song J.S. Lee E.W. Park H.W. 《Multimedia Tools and Applications》2000,11(2):197-214
A real-time MPEG-2 video codec system, called the KAIST image computing system (KICS), was developed using multiple multimedia video processors (MVP, TMS320C80). The number of computations and optimum implementation of the MPEG-2 algorithm were analyzed for real-time processing. An MVP simulator was used to perform the timing analysis for the real-time MPEG-2 encoding and decoding, and it verified the design of the KICS. Task partitioning and mapping of the MPEG-2 algorithm to multiple MVPs were performed based on load-balancing, minimum data I/O, and the properties of the MVP. The KICS uses five MVPs for MPEG-2 real-time encoding of a main profile at the main level whereas it uses three MVPs for real-time decoding. 相似文献
953.
This paper introduces a novel neurofuzzy system based on polynomial fuzzy neural network (PFNN) architecture. A PFNN consists
of a set of if-then rules with appropriate membership functions (MFs) whose parameters are optimized via a hybrid genetic
algorithm. A polynomial neural network is employed in the defuzzification scheme to improve output performance and to select
appropriate rules. A performance criterion for model selection is defined to overcome the overfitting problem in the modeling
procedure. For a performance assessment of the PFNN inference system, two well-known problems are employed for a comparison
with other methods. The results of these comparisons show that the PFNN inference system out-performs the other methods and
exhibits robustness characteristics.
This work was presented in part at the Fourth International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–22, 1999 相似文献
954.
955.
Lee WH 《Applied optics》1984,23(23):4280-4284
Charge coupled device (CCD) image sensors are currently used in many image processing applications such as facsimile and bar code reading. Because the photodetectors in the device have finite areas, the output signal from the CCD image sensor is only an approximation to the sampled value of the image. In this paper we discuss the reconstruction of bar codes from the imperfect CCD signal by digital signal processing techniques. Schemes for encoding digital data in the form of bar codes are also discussed. 相似文献
956.
Lawrence E. Matson Helmut Erhart Moonyong Lee Robert A. Rapp 《Metallurgical and Materials Transactions A》1984,15(12):2241-2246
In situ oxidation of polycrystalline iron at 1200 °C and
atm has revealed symmetrical square growth pits in the wustite scale. The pit walls are nominally oriented with the {110}
planes of the wustite lattice but are dissociated into macro- and microledges consisting of {100}-type planes. Such growth
pits intrude into the wustite scale at the gas/oxide interface, and at the oxide/metal interface small oxide nodules intrude
into the metal. After sufficiently long oxidation times at 1200 °C, rate control should shift from oxidant arrival to cation
volume diffusion, and pits are then destabilized and a planar morphology is achieved. 相似文献
957.
Several superlattices (SL's) with different layer thicknesses, grown by molecular beam epitaxy (MBE), were disordered via low temperature (550?600°C) Zn diffusions to investigate layer thickness effects on both the Zn diffusion process and the Al-Ga interdiffusion process. The Zn diffusion coefficients were measured using secondary ion mass spectroscopy (SIMS) and Auger electron spectroscopy (AES) and found to be ?10?12 cm2/sec, increasing somewhat with decreasing layer thickness. The activation energy for the Zn diffusion process ranged from 3.1 eV for an 1100Å/period SL to 2.1 eV for a 320Å/period SL. The Al-Ga interdiffusion coefficient and the activation energy associated with the interdiffusion process were calculated from AES depth profiles. The coefficient is on the order of 10?16 cm2/sec and the activation energy is approximately 1 eV, independent of the SL layer thickness. 相似文献
958.
A generalized correlation is developed for the viscosity and thermal conductivity of isotropic fluids under high pressures (up to 200 MPa) and low temperatures (down to 85 K). Two known observations have been taken into consideration in the development of the correlation. First, the Alder correction factors for the Enskog theory values of transport coefficients obtained from molecular dynamics simulations for hard sphere fluids are incorporated. The inclusion of these corrections in the theory makes it possible to describe correctly the density dependence of the hard sphere viscosity and thermal conductivity at high pressures. The hydrodynamic cage effect, which is manifested in the molecular motions of dense fluid systems, is thus correctly accounted for. Second, the generalized Eucken relation, which relates the thermal conductivity to the viscosity, is incorporated. As a consequence, an internally consistent correlation is obtained, which can adequately predict the behavior of the thermal conductivity from given values of viscosity. Tests on simple fluids, such as argon, krypton, etc., show that the correlation is valid within a few percent for the entire fluid range where experimental data are available for comparison, and also along the vapor-liquid saturation line, with the exclusion of the critical region. Furthermore, since the variables appearing in the theory are in reduced form, a corresponding states correlation is established for isotropic fluids. 相似文献
959.
During liquid phase sintering solid particles move about within the liquid and make contact with each other. Microstructural
examination of liquid phase sintered alloys clearly indicates that some of these contacts lead to particle coalescence even
in systems in which wetting of the solid by the liquid is presumed to occur. Under these circumstances, the grain boundary
formed by the particles must have a rather low energy and hence, misorientation. In this study, attention is directed at the
problem of calculating the probability of a collision between particles that lead to the formation of a low angle grain boundary
and hence, coalescence. By making simple but physically plausible assumptions about the nature of low angle grain boundaries,
the coalescence probabilityp
c
can be determined as a function of a parameterθ where θ =
withγ
SL
=solid-liquid surface energy,γ
ss
= average solid-solid grain boundary energy and У is the angular extent of the energy cusp associated with a low angle grain
boundary. A simple analytical expression ofp
c
,p
c
= 0.1θ (1-cosθ) is derived and found to be in excellent agreement with other techniques for calculatingp
c
for values ofθ ≲ 10 deg, the range most probable for liquid phase sintered alloys. Some discussion of the accuracy and assumptions of the
present model is also given. 相似文献
960.
In this paper, we extend the binary Gray code to symbolic Gray code. We then show that this symbolic Gray code can be used as a multikey hashing function for storing symbolic records. The record stored at location k and the record stored at location k + 1 will be nearest neighbors if this hashing function is used. Thus, this symbolic Gray code hashing function exhibits some kind of clustering property which will group similar records together. This property is a desirable property for designing nearest neighbor searching (also called best match searching) systems. There are many other interesting properties of this hashing function. For instance, there exists an address-to-key transformation which can be used to determine the record stored at certain location k if this hashing function is used. Besides, if there are totally M records, we only have to reserve exactly M locations; there are no collisions and wasting of memory storage. At the end of this paper, it is shown that the resulting file exhibits the multiple-attribute tree structure. 相似文献