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71.
Ashesh K. Sinha W.J. Zhang M.K. Tiwari 《Engineering Applications of Artificial Intelligence》2012,25(8):1628-1643
This article is betrothed to serve as a continuation of the emerging swarm techniques to solve supply chain problems. Our aim is to map some of the pressing research challenges contributed by the artificial intelligence community and to develop an improved algorithm: Co-evolutionary immuno-particle swarm optimisation with penetrated hyper-mutation (COIPSO-PHM). In this paper, we proposed a new algorithm which uses clonal selection approach in particle swarm optimisation by embedding co-evolutionary theory to solve the problem of inventory replenishment in distributed plant–warehouse–retailer system. Constraint handling is explicitly taken care by implanting augmented lagrangian concept. To demonstrate the efficiency of the algorithm, its performance are evaluated and compared on 10 benchmarked problems (made constrained problem via random initialisation in the infeasible zone) including functions with uni-modalities as well as multi-modalities. The result follows shows superior performance of the algorithm in every respect. 相似文献
72.
VA Belitser TV Varetskaia SN Tsynkalovskaia LA Tsariuk LI Shevchenko 《Canadian Metallurgical Quarterly》1976,48(4):521-532
A new diagnostic method to determine fibrinogen and fibrin splitting products is based on the fact that high-molecular fragments acting as specific inhibitors of fibrin self-assembly compose these products. Fibrinogen and fibrin splitting products are detected and determined quantitatively by prolongation of coagulation time in the test with the standard monomeric fibrin. The number of units of anticoagulating activity in the studied urine are the results of the determinations. Sensitivity of the method if necessary may be increased by adding of a certain amount of the fibrinogen and fibrin splitting products to the test that makes a favourable background for the action of the products. The method is rather sensitive, reliable and simple. It may be used in ordinary clinical laboratories. The method proved to be quite satisfactory when testing renal diseases at the clinic. It is of great significance for early detection of the transplanted kidney rejection. The new method is compared with the known immunological method which consist in determination of the inhibitory effect of the fibrinogen and fibrin splitting products on agglutination of erythrocytes of specific antibodies; the erythrocytes being subjected to "tanning" and "loading" with fibrinogen. A satisfactory correlation is found between the results of two methods. 相似文献
73.
This paper analyses the stability of a parametrically excited double pendulum rotating in the horizontal plane. The equations of motion for such a system contain time varying periodic coefficients. Floquet theory and the method of Hill's determinant are used to evaluate the stability of the linearized system. Stability charts are obtained for various sets of damping, parametric excitation, and rotation parameters. Several resonance conditions are found, and it is shown that the system stability can be significantly altered due to the rotation. Such systems can be used as preliminary models for studying the lag dynamics and control of helicopter blades and other gyroscopic systems. 相似文献
74.
Avinash kumar Agrawal Shrawan Kumar Singh Shailendra Sinha Mritunjay Kumar Shukla 《Sadhana》2004,29(3):275-284
In diesel engines, NOx formation is a highly temperature-dependent phenomenon and takes place when the temperature in the
combustion chamber exceeds 2000 K. Therefore, in order to reduce NOx emissions in the exhaust, it is necessary to keep peak
combustion temperatures under control.
One simple way of reducing the NOx emission of a diesel engine is by late injection of fuel into the combustion chamber. This
technique is effective but increases fuel consumption by 10–15%, which necessitates the use of more effective NOx reduction
techniques like exhaust gas recirculation (EGR). Re-circulating part of the exhaust gas helps in reducing NOx, but appreciable
paniculate emissions are observed at high loads, hence there is a trade-off between NOx and smoke emission. To get maximum
benefit from this trade-off, a paniculate trap may be used to reduce the amount of unburnt particulates in EGR, which in turn
reduce the paniculate emission also.
An experimental investigation was conducted to observe the effect of exhaust gas re-circulation on the exhaust gas temperatures
and exhaust opacity. The experimental setup for the proposed experiments was developed on a two-cylinder, direct injection,
air-cooled, compression ignition engine. A matrix of experiments was conducted for observing the effect of different quantities
of EGR on exhaust gas temperatures and opacity 相似文献
75.
A theoretical model has been developed to study the local heat transfer coefficient of a condensing vapour in the presence of a noncondensable gas, where the gas/vapour mixture is flowing downward inside a vertical tube. The two-phase heat transfer is analysed using an annular flow pattern with a liquid film at the tube wall and a turbulent gas/vapour core. The gas/vapour core is modeled using the analogy between heat and mass transfer. The model incorporates Nusselt equation with McAdams modifier and Blangetti model for calculating the film heat transfer coefficient, Moody and Wallis correlations to account for film waviness effect on gas/vapour boundary layer. The suction effect due to condensation, developing flow and property variation of the gas phase is also considered. A comparative study of heat transfer coefficient and vapour mass flow rate has been made with various models to account for condensate film resistance and condensate film roughness. Results show that for very high Reynolds number, the condensation heat transfer coefficient is higher than the film heat transfer coefficient. 相似文献
76.
In this paper, the influence of single walled carbon nano tubes (SWCNTs) addition on the tribological properties of the polyimide
(PI) films on silicon substrate was studied. PI films, with and without SWCNTs, were spin coated onto the Si surface. Coefficient
of friction and wear durability were characterized using a ball-on-disk tribometer by employing a 4 mm diameter Si3N4 ball sliding against the film, at a contact pressure of ∼370 MPa, and a sliding velocity of 0.042 ms−1. Water contact angle, AFM topography, and nano-indentation tests were conducted to study the physical and mechanical properties
of the films. SWCNTs marginally increased the water contact angle of PI film. The addition of SWCNTs to PI has increased the
hardness and elastic modulus of pristine PI films by 60–70%. The coefficient of friction of PI films increased slightly (∼20%)
after the addition of SWCNTs, whereas, there was at least two-fold increase in the wear life of the film based on the film
failure condition of coefficient of friction higher than 0.3. However, the film did not show any sign of wear even after 100,000
cycles of rotation indicating its robustness. This increase in the wear durability due to the addition of the SWCNTs is believed
to be because of the improvement in the load-bearing capacity of the composite film and sliding induced microstructural changes
of the composite film. 相似文献
77.
The performance of an idealized step slider bearing with a viscoelastic lubricant is investigated theoretically. The elasticity of the lubricant is characterized by a dimensionless number α. The effects of the elasticity of the lubricant on the pressure, load-bearing capacity, frictional resistance, coefficient of friction and maximum film thickness were studied in detail and are presented in several graphs and tables. 相似文献
78.
We consider a nonstatic, spin-polarized cylindrically symmetric perfect fluid distribution in the Einstein-Cartan theory and obtain the field equations. These field equations are solved using the Ray–Smalley energy-momentum tensor. 相似文献
79.
For 32/22 nm technology nodes and below, double patterning (DP) lithography has become the most promising interim solutions due to the delay in the deployment of next generation lithography (e.g., EUV). DP requires the partitioning of the layout patterns into two different masks, a procedure called layout decomposition. Layout decomposition is a key computational step that is necessary for double patterning technology. Existing works on layout decomposition are all single-threaded, which is not scalable in runtime and/or memory for large industrial layouts. This paper presents the first window-based parallel layout decomposition methods for improving both runtime and memory consumption. Experimental results are promising and show the presented parallel layout decomposition methods obtain upto 21× speedup in runtime and upto 7.5×reduction in peak memory consumption with acceptable solution quality. 相似文献
80.
A new approach is proposed for determining the robust stability of discrete-time systems where each coefficient of the characteristic polynomial can take any value between specified lower and upper bounds. It is based on the use of Rouche's theorem in the theory of complex variables. 相似文献