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131.
Several biclustering algorithms have been proposed in different fields of microarray data analysis. We present a new approach that improves their performance in using the ensemble methods. An ensemble biclustering is considered and formalized by a problem of binary triclustering. We propose a simple and efficient algorithm to solve it. To illustrate the interest of our ensemble approach, numerical experiments are performed on both artificial and real datasets with two biclustering algorithms commonly used in bioinformatics. 相似文献
132.
Mohamed Djendi Author Vitae 《Computers & Electrical Engineering》2012,38(4):938-952
This paper addresses the field of stereophonic acoustic echo cancellation (SAEC) by adaptive filtering algorithms. Recently, we have proposed a new version of the fast Newton transversal FNTF algorithm for SAEC applications. In this paper, we propose an efficient modification of this algorithm for the same applications. This new algorithm uses a new proposed and simplified numerical stabilization technique and takes into account the cross-correlation between the inputs of the channels. The basic idea is to introduce a small nonlinearity into each channel that has the effect of reducing the inter-channel coherence while not being noticeable for speech due to self masking. The complexity of the proposed algorithm does not alter the complexity of the original version and is kept less than half the complexity of the fastest two-channel FTF filter version. Simulation results and comparisons with the extended two-channel normalized least mean square NLMS and FTF algorithms are presented. 相似文献
133.
134.
There is an increasing recognition for the need to develop high quality use case models from the professional and academic communities. Quality in use case models is of particular importance when they are utilized within a use case driven development process, whereby every aspect of development is driven by the models and influenced by their quality. Many practitioners and researchers have provided guidelines, suggestions and techniques to construct high quality use case models. This invaluable body of knowledge is disseminated across numerous literature resources. Without unifying this knowledge into one resource, it cannot be expected that a use case modeler would be fully aware of the entire body of knowledge and benefitting from it. This paper presents a systematic review that was conducted in order to identify and amalgamate this knowledge. The amalgamated knowledge is presented in a unified form, specifically as a set of 26 anti-patterns, which modelers can use to improve the quality of their models. 相似文献
135.
Two modified electrodes (Pb/PbO2 and C/PbO2) were prepared by electrodepositing a lead oxide layer on lead and carbon sub-strates. These modified electrodes were used as anodes for the generation of sodium hypochlorite (NaOCl) from sodium chloride solution. Different operating conditions and factors affecting the treatment process of NaOCl generation, including current density, pH values, con-ductive electrolytes, and electrolysis time, were studied and optimized. By comparison the C/PbO2 electrode shows a higher efficiency than the Pb/PbO2 electrode for the generation of NaOCl. 相似文献
136.
Hussain Shareef Azah Mohamed Saifunizam Abd. Khalid Mohd Wazir Mustafa 《中南工业大学学报(英文版)》2012,19(1):179-186
A multivariable regression (MVR) approach is proposed to identify the real power transfer between generators and loads. Based
on solved load flow results, it first uses modified nodal equation method (MNE) to determine real power contribution from
each generator to loads. Then, the results of MNE method and load flow information are utilized to determine suitable regression
coefficients using MVR model to estimate the power transfer. The 25-bus equivalent system of south Malaysia is utilized as
a test system to illustrate the effectiveness of the MVR output compared to that of the MNE method. The error of the estimate
of MVR method ranges from 0.001 4 to 0.007 9. Furthermore, when compared to MNE method, MVR method computes generator contribution
to loads within 26.40 ms whereas the MNE method takes 360 ms for the calculation of same real power transfer allocation. Therefore,
MVR method is more suitable for real time power transfer allocation. 相似文献
137.
138.
139.
Etch-pit (EP) technique and transmission electron microscopy (TEM) have been used to investigate the subgrain size, , as a function of applied shear stress, , during high-temperature creep of aluminium. Examination of thin foils, prepared from deformed specimens, in the electron microscope shows the presence of very large equiaxed sub-grains that approximate those observed in etch-pit photographs. By measuring the average subgrain size from transmission micrographs of representative areas of the foils, two observations are made. First, the average subgrain size is smaller than that determined from etch-pit procedure, but exhibits the same stress dependence: /b (/G)– where b is the Burgers vector and G is the shear modulus. Second, the TEM subgrain size data of aluminium and those of other metals and alloys, when plotted in the normalized form of /Gb against /Gb on a logarithmic scale, where is the stacking-fault energy of the material, fall within a narrow, horizontal band, confirming earlier reports that the subgrain size is insensitive to stacking-fault energy. 相似文献
140.
P.C-H. Chan D.G. Retzloff R. Mohamed B. Berdouzi C. Chicone D. Offin 《Chemical Engineering Communications》1987,57(1):105-138
The dynamical behavior for two parallel reactions in a continuous stirred tank reactor (CSTR) is considered. The global maximum number of steady states is five. Stability conditions are obtained. When the steady state is unique and unstable, a circulating attractor is proven to exist. The orbit structure is numerically found to consist of periodic orbits and chaotic behavior. 相似文献