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41.
Canonical correlation analysis (CCA) is one of popular statistical methodologies in multivariate analysis, especially, in studying relation of two sets of variables. However, if sample sizes are smaller than the maximum of the dimensions of two sets of variables, it is not plausible to construct canonical coefficient matrices due to failure of inverting sample covariance matrices. In this article, we develop a two step procedure of CCA implemented in such situation. For this, seeded dimension reduction is adapted into CCA. Numerical studies confirm the approach, and two real data analyses are presented. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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The design variable tolerance effects on the natural frequency variance of constrained multi-body systems in dynamic equilibrium are investigated in this study. Monte-Carlo simulation is often employed for such investigations, but it is known to have serious drawbacks. Excessive amount of computation time needs to be consumed since a large number of evaluations are usually required for the method. Furthermore, the solution accuracy cannot be always guaranteed in spite of the excessive amount of computation time. In order to overcome such drawbacks, a method employing eigenvalue sensitivity information is proposed to obtain the variance of natural frequency in this study. In order to verify the accuracy and the efficiency of the method, some numerical examples of multi-body systems in dynamic equilibrium are solved and the results are compared to those obtained by an analytical method and Monte-Carlo simulation. 相似文献
44.
The planar laser-induced fluorescence (PLIF) imaging method was used to perform flow visualization and quantitative planar
thermometry in shock tube flow fields using toluene as a fluorescence tracer in nitrogen. Fluorescence quantum yield values
needed to quantify PLIF images were measured in a static cell at low pressures (<1 bar) for various toluene partial pressures
in nitrogen bath gas. Images behind incident and reflected shocks were taken in the core flow away from regions affected by
boundary layers. Temperature measurements from these images were successfully compared with predicted values using ideal shock
equations. Measured temperatures ranged between 296 and 800 K and pressures between 0.15 and 1.5 atm. The average temperature
discrepancies between measurements and the predicted values behind the incident and reflected shocks were 1.6 and 3.6%, respectively.
Statistical analyses were also conducted to calculate the temperature measurement uncertainty as a function of image resolution.
The technique was also applied to the study of more complex supersonic flows, specifically the interaction of a moving shock
with a wedge. Measured temperatures agreed well with the results of numerical simulations in all inviscid regions, and all
pertinent features of the single Mach reflection were resolved. 相似文献
45.
Investigation of the effect of electron cyclotron heating on runaway generation in the KSTAR tokamak
Z.Y. Chen W.C. KimA.C. England S.W. YoonK.D. Lee Y.S. LeeJ.W. Yoo Y.W. YuY.K. Oh J.G. KwakM. Kwon 《Physics letters. A》2011,375(26):2569-2572
Wave enhanced runaway generation is expected to play an important role in the conversion of plasma current into runaway current during major disruptions. The fast electrons created by electron cyclotron heating (ECH) were used to study this issue in KSTAR. It is found that the fast electrons driven by ECH can enhance runaway production in the flat top phase with high loop voltage. The runaway current in disruptions was not enhanced by the ECH produced fast electron population due to the strong magnetic fluctuations which inhibited the generation of runaway electrons. It is found that a complete loss of existing REs during thermal quench has occurred in KSTAR limiter configuration discharges. 相似文献
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We present an integrated algorithm on a Eulerian grid, for multimaterial simulations of energetic and inert materials modelled by non-ideal equations of state. We employ high-resolution shock capturing numerical algorithms for each material inside its domain and use an overlap domain method across the interface, maintained by a recently developed, hybrid, level-set algorithm. For applications to condensed explosives we implement a non-ideal, wide-ranging equation of state and reaction rate law. For inert materials, like plastic, metal, water, etc., we implement a (linear in the pressure) Mie–Grüneisen, (U p ?U s ), equation of state. We present a series of verifications of the integrated multimaterial code and show validations against experiment. We show examples of simulations of various experiments associated with real or planned experiments, some of which contain energetic materials (specifically the condensed explosives PBX-9502 and PBX-9501). 相似文献
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