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991.
Taguchi's data programming techniques in synergy with data analysis tactics based on artificial neural networks have been fruitful in illuminating intricate manufacturing phenomena. We present a non-parametric approach to treat multi-response multi-factorial datasets created with Taguchi's orthogonal-array samplers. Replicated response datasets are compressed utilizing the signal to noise ratio and then they are homogenized by simple rank-ordering. The multiple response layout is reduced to the more tractable uni-response arrangement by using the super-ranking concept to enact the fusing of the individual responses. The ‘ranked-and-fused’ dataset is subjected to conversion by linear and three-layer perceptrons. The performance of a group of examined effects is assessed according to the perceptrons’ sensitivity analysis output. Using Wilcoxon's one-sample test, statistical significance is assigned to the accumulated ranking scores obtainable from a series of independent perceptron runs. We discuss the efficiency status for each of the two engaged perceptron options on affecting prediction accuracy as well as the influence of data fusion on the SNR-compressed datasets. Our robust neurocomputing solver is elucidated in a concurrent screening of three foam characteristics which are encountered in popular solar-collector assembly operations. Seven controlling factors were profiled and it was found that the temperature of the polyol additive is the sole statistically predominant effect. Finally, through our industrial paradigm, we illustrate the superiority of the fusing principle for downsizing stochastically multiple characteristics and thus gaining faster and more accurate perceptron predictions. We show that the proposed method outperforms the outcomes obtained by the desirability analysis. We identify the points of superiority to the crisper resolution in locating effect dominance accompanied with recovered stochastic significance. 相似文献
992.
泵站机组测温系统是监视、保护机组机电部分安全运行的重要系统。测温热电阻的测量原理是测温热电阻值随测点温度变化而变化,根据反馈电压的大小,测量出热电阻阻值,从而计算出测点温度,测温热电阻的常见故障是热电阻的短路和断路,有效地检测测温系统中经常出现的故障并及时处理,是泵站安全运行的有力保障。 相似文献
993.
《Journal of the European Ceramic Society》2014,34(5):1365-1373
In this work, Al2O3 self-flowing castables (SFCs) were produced based on various cement contents. The SFCs were sintered at 1273 K, 1573 K and 1773 K and the exhibited properties were experimentally determined. Among the properties determined in this work are bulk density (BD), apparent porosity (AP), water absorption (WA), cold crushing strength (CCS), modulus of rupture (MOR) and fracture toughness (KIC). It is found that additions of 5% cement lead to SFCs with maximum MOR and KIC values after firing at 1773 K. Firing at 1573 K leads to a reduction in both, MOR and KIC. In SFC containing 3% cement, maximum KIC values of 3.53 MPa m1/2 were achieved after firing at 1573 K. In the low cement SFCs (1 wt%) after firing at 1773 K the exhibited KIC values were below those obtained in either the SFC-3 or SFC-5, but they were significantly high (3.43 MPa m1/2). 相似文献
994.
利用基于密度泛函理论的第一性原理研究了黄铜矿CuCrS2的电子结构。结果表明:CuCrS2是一种半金属铁磁体,其半金属隙为0.18eV。每个CuCrS2分子的磁矩为3.00μB,Cr原子是分子磁矩的主要贡献者。晶胞体积变化时,各原子磁矩呈现不同的变化趋势,但Cr原子仍为分子磁矩的主要来源,晶胞体积增大5%和10%时,CuCrS2依然能表现出良好的半金属性。 相似文献
995.
The aim of this study was to investigate the usefulness of combined application of quality by design tools such as central composite design (CCD), response surface methodology (RSM), and artificial neural networks (ANN) in the characterization, modeling, and optimizaton of spray drying of a poorly soluble drug : cyclodextrin complex. Models were developed by RSM and ANN from different pools of data. The model with best predictability was the ANN multilayer perceptron (MLP)1 model developed from the largest group of data (R 2 for response yield 0.854, moisture content 0.886). On the other hand, analysis of equations derived from the application of RSM contributed in better understanding the complex relationships between input and output variables. By application of a desirability function approach, optimal process parameters that resulted in the best process yield (86%) and minimal moisture content in the powder (3.3%) were established (25% feed concentration, 180°C inlet air temperature, 10% pump speed). 相似文献
996.
In this paper, we numerically study particle formation in the rapid expansion of supercritical solution (RESS) process in a two dimensional, axisymmetric geometry, for a benzoic acid + CO2 system. The fluid is described by the classical Navier–Stokes equation, with the thermodynamic pressure being replaced by a generalized pressure tensor. Homogenous particle nucleation, transport, condensation and coagulation are described by a general dynamic equation, which is solved using the method of moments. The results show that the maximal nucleation rate and number density occurs near the nozzle exit, and particle precipitation inside the nozzle might not be ignored. Particles grow mainly across the shocks. Fluid in the shear layer of the jet shows a relatively low temperature, high nucleation rate, and carries particles with small sizes. On the plate, particles within the jet have smaller average size and higher geometric mean, while particles outside the jet shows a larger average size and a lower geometric mean. Increasing the preexpansion temperature will increase both the average particle size and standard deviation. The preexpansion pressure does not show a monotonic dependency with the average particle size. Increasing the distance between the plate and the nozzle exit might decrease the particle size. For all the cases in this paper, the average particle size on the plate is on the order of tens of nanometers. 相似文献
997.
998.
999.
为调动学生自主学习兴趣,培养其解决工程实际问题的能力和创新能力,我们对化工原理课程(理论课、实验课和课程设计)的授课方式等进行了改进,即在教师的配备、教学内容及时间的设置上,进行了改进,并提出了改进的具体措施,取得了成效。 相似文献
1000.