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11.
In this paper, a novel stochastic two-sided U-type assembly line balancing (STUALB) procedure, an algorithm based on the genetic algorithm and a heuristic priority rule-based procedure to solve STUALB problem are proposed. With this new proposed assembly line design, all advantages of both two-sided assembly lines and U-type assembly lines are combined. Due to the variability of the real-life conditions, stochastic task times are also considered in the study. The proposed approach aims to minimise the number of positions (i.e. the U-type assembly line length) as the primary objective and to minimise the number of stations (i.e. the number of operators) as a secondary objective for a given cycle time. An example problem is solved to illustrate the proposed approach. In order to evaluate the efficiency of the proposed algorithm, test problems taken from the literature are used. The experimental results show that the proposed approach performs well. 相似文献
12.
M. O. Petrushkov M. A. Putyato I. B. Chistokhin B. R. Semyagin E. A. Emel’yanov M. Yu. Esin T. A. Gavrilova A. V. Vasev V. V. Preobrazhenskii 《Technical Physics Letters》2018,44(7):612-614
An original technology of zinc diffusion into InP via a narrow gap is described, which allows reproducible formation of p–n junctions with preset depth of doping and retained surface morphology of the doped layers. Using the proposed method, desired charge carrier distribution profiles in Zn-doped InP layers were obtained. It has been experimentally confirmed that the method of cross-sectional scanning electron microscopy allows to precision measure of the zinc diffusion depth. 相似文献
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14.
Micro-milling performance of AISI 304 stainless steel using Taguchi method and fuzzy logic modelling
In this study, micro-milling of AISI 304 stainless steel with ball nose end mill was conducted using Taguchi method. The influences of spindle speed, feed rate and depth of cut on tool wear, cutting forces and surface roughness were examined. Taguchi’s signal to noise ratio was utilized to optimize the output responses. The influence of control parameters on output responses was determined by analysis of variance. In this study, the models describing the relationship between the independent variables and the dependent variables were also established by using regression and fuzzy logic. Efficiency of both models was determined by analyzing correlation coefficients and by comparing with experimental values. The results showed that both regression and fuzzy logic modelling could be efficiently utilized for the prediction of tool wear, cutting forces and surface roughness in micro-milling of AISI 304 stainless steel. 相似文献
15.
V. F. Savchenko L. V. Makhnach I. I. Emel’yanova V. V. Pan’kov 《Inorganic Materials》2006,42(7):788-793
The formation of LaSrNiO4-and LaSrScO4-based solid solutions with the general stoichiometry LaSrNi1 ? x ScxO4 (0 < x < 1) has been studied in air at temperatures from 700 to 1300°C. According to x-ray diffraction results, the former solid solutions exist in the composition range 0 < x ≤ 0.2. Their lattice parameters have been determined, and their resistivity and thermoelectric power have been measured as functions of temperature. Oxygen release and absorption measurements at temperatures from 20 to 1000°C and oxygen partial pressures from 2 to 330 Pa suggest that the presence of scandium has a stabilizing effect on the oxygen sublattice of the solid solutions. The possible mechanisms of this effect are discussed. 相似文献
16.
Experimental investigation of the current-induced breakage of metal-coated polymer films 总被引:1,自引:0,他引:1
We have experimentally studied the phenomenon of current-induced breakage of thin (∼20-to 30-nm-thick) metal films deposited
onto poly(ethylene terephthalate) (PETP) and poly(propylene) (PP) substrates. Two mechanisms leading to the current-induced
breakage of the metal film are established, which are characterized by different average threshold current densities: j
H ∼ 1.5 × 1010 A/m2 and j
L ∼ 0.7 × 1010 A/m2. The possible nature of these mechanisms is discussed. 相似文献
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A. M. Emel’yanov 《Semiconductors》2013,47(1):110-115
The experimental results and model representations of the edge electroluminescence of two published studies for small-area silicon p +-n diodes heavily doped with boron are analyzed. In one of these studies it was assumed that edge electroluminescence appears in the p + region of the diode, and in the other, in the n region of the diode. In the latter case, it was demonstrated that electroluminescence indeed arose in the n region and was caused predominantly by the radiative recombination of free excitons. It is shown that similar model concepts are also applicable to the other study. Based on several independent experimental studies (of edge photoluminescence, electroluminescence, and radiation absorption by free carriers), it is demonstrated that the linear or close-to-linear dependences of the edge-luminescence intensity on the excitation intensity, observed in single-crystal silicon at high injection levels, are caused by the close-to-linear dependences of the exciton concentration on the free-carrier concentration. The results of this study extend the capability of luminescence methods for determining the carrier lifetimes to the region of high injection levels. 相似文献