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排序方式: 共有10000条查询结果,搜索用时 62 毫秒
991.
The paper firstly defined the remote sensing information quantification, analyzed the necessity of developing remote sensing quantification, figured out the application guidelines requirement, and pointed out the importance of quantification research. Then taking the remote sensing application research of CBERS-02 data quantification as the example, the paper described the whole quantification system of “remotely sensed digital signal-radiation information-field parameter inversion”. Finally the paper gave the prospect for the development trend of the quantitative remote sensing. 相似文献
992.
993.
Jan Paca Eva Klapkova Martin Halecky Kim Jones Carlos Riccardo Soccol 《Clean Technologies and Environmental Policy》2007,9(1):69-74
The removal of a mixture of painting solvents from waste air using a biofiltration process was evaluated in this project.
The pollutants removed included hydrophobic (aromatic hydrocarbons) and hydrophilic (water soluble ketones and esters) compounds.
A trickle bed reactor with a defined immobilized mixed culture on polyethylene Pall rings was utilized in this biodegradation
study. The removal efficiencies (RE) of the individual groups of pollutants during loading experiments were determined. An
increase of the aromatic hydrocarbons loading resulted in a drop of their REAROM with no effect on the RE value of ketones. The overloading of ketones caused a rapid drop in REAROM and a small drop in REKET. To achieve a restoration of the biocatalyst degradation properties after the increase in loading, an addition of phosphate
to the aqueous medium was implemented which successfully restored the removal efficiency. 相似文献
994.
We have studied the effect of illumination on the current-voltage characteristics and the temperature dependence of conductivity of MnGaInS4 single crystals. Under illumination, the current in a sample was 104–105 times the dark value. It is established that the light-induced current buildup is due to the carrier release from the traps filled under illumination. The energy positions of levels are determined. 相似文献
995.
S. W. Cheong E. J. Hilinski A. D. Rollett 《Metallurgical and Materials Transactions A》2003,34(6):1321-1327
This article attempts to determine the mechanisms governing the grain growth process that occurs during lamination annealing
of a cold-rolled, motor-lamination (CRML) steel. A new simulation approach linking a Monte Carlo model with electron backscatter
diffraction (EBSD) scans used as input has been employed to incorporate the effects of crystallographic texture on the simulated
grain growth process. The results from the texture analysis and the computer simulation of the grain growth process indicate
that both stored energy driven grain growth and anisotropic grain boundary growth influence the overall grain growth occurring
during lamination annealing. 相似文献
996.
A semiautomated electron backscatter diffraction technique for extracting reliable twin statistics 总被引:2,自引:0,他引:2
B. L. Henrie T. A. Mason B. L. Hansen 《Metallurgical and Materials Transactions A》2004,35(12):3745-3751
A framework has been developed for extracting reliable twin statistics from a deformed microstructure using crystallographic
twin identification techniques with spatially correlated electron backscatter diffraction (EBSD) data. The key features of
this analysis are the use of the mathematical definition of twin relationships, the inclination of the common K
1 plane at a twin boundary, and the correct identification of the parent orientation in a parent/twin pair. Methods for identifying
the parent in a parent/twin pair will be briefly discussed and compared. Twin area fractions are then categorized by operative
twin systems, number of active twin variants in each system, and corrected twin widths. These statistics are reported here
for α-zirconium samples deformed in quasi-static four-point bend beams and in a 100 m/s Taylor cylinder impact test. Analysis of
the statistics also begins to reveal the roles that deformation rate and relative orientation of the boundary conditions to
the material’s symmetry axes play in determining the twinning activity that accommodates the imposed boundary conditions.
These improved twin statistics can help quantify the deformation processes in materials that deform by twinning as well as
serve to provide better validation of proposed models of the deformation processes. 相似文献
997.
Twenty-five years of natural coordinates 总被引:3,自引:0,他引:3
Javier García de Jalón 《Multibody System Dynamics》2007,18(1):15-33
In the early eighties, the author and co-workers created and further developed the natural coordinates to describe the motion
of 2-D and 3-D multibody systems. Natural coordinates do not need angles or angular parameters to define orientation, leading
to constant inertia matrices and to the simplest form of the constraint equations. Natural coordinates are composed by the
Cartesian coordinates of some points and the Cartesian components of some unit vectors distributed on the different bodies
of the system. The points and vectors can be located in the joints, being shared by contiguous bodies, decreasing or even
eliminating the need to set joint constraints and reducing the total number of variables. However, other authors prefer not
to share variables in order to get even simpler equations and to keep a bigger decoupling of equations, which is preferable
in some cases.
In this paper the history of natural coordinates is reviewed, as well as the main contributions coming from other research
groups. In the second part of the paper some application areas in which natural coordinates can be particularly advantageous
are examined.
Commemorative Contribution. 相似文献
998.
Dynamic neural networks with different time-scales include the aspects of fast and slow phenomenons. Some applications require
that the equilibrium points of the designed networks are stable. In this paper, the passivity-based approach is used to derive
stability conditions for dynamic neural networks with different time-scales. Several stability properties, such as passivity,
asymptotic stability, input-to-state stability and bounded input bounded output stability, are guaranteed in certain senses.
A numerical example is also given to demonstrate the effectiveness of the theoretical results. 相似文献
999.
Gloria Galan-Marin Enrique Merida-Casermeiro Domingo Lopez-Rodriguez 《Neural Processing Letters》2007,26(2):133-143
Detection of isomorphism among kinematic chains is essential in mechanical design, but difficult and computationally expensive.
It has been shown that both traditional methods and previously presented neural networks still have a lot to be desired in
aspects such as simplifying procedure of identification and adapting automatic computation. Therefore, a new algorithm based
on a competitive Hopfield network is developed for automatic computation in the kinematic chain isomorphism problem. The neural
approach provides directly interpretable solutions and does not demand tuning of parameters. We have tested the algorithm
by solving problems reported in the recent mechanical literature. Simulation results show the effectiveness of the network
that rapidly identifies isomorphic kinematic chains. 相似文献
1000.
Motion picture films are susceptible to local degradations such as dust spots. Other deteriorations are global such as intensity
and spatial jitter. It is obvious that motion needs to be compensated for before the detection/correction of such local and
dynamic defects. Therefore, we propose a hierarchical motion estimation method ideally suited for high resolution film sequences.
This recursive block-based motion estimator relies on an adaptive search strategy and Radon projections to improve processing
speed. The localization of dust particles then becomes straightforward. Thus, it is achieved by simple inter-frame differences
between the current image and motion compensated successive and preceding frames. However, the detection of spatial and intensity
jitter requires a specific process taking advantage of the high temporal correlation in the image sequence. In this paper,
we present our motion compensation-based algorithms for removing dust spots, spatial and intensity jitter in degraded motion
pictures. Experimental results are presented showing the usefulness of our motion estimator for film restoration at reasonable
computational costs.
Received: 9 July 2000 / Accepted: 13 January 2002
Correspondence to:S. Boukir 相似文献