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101.
将竞争机理引入网络的自动波产生与传播过程中,提出自动波竞争神经网络(ACNN)模型,并成功地应用于求解单源最短路问题,给出了基于ACNN的最短路求解算法. 与其他神经网络最短路算法相比,基于ACNN的最短路算法具有网络所需的神经元数目少、神经元及网络的结构简单、易于软硬件的实现、以及全并行方式计算等特点,可用于求解非对称赋权图的最短路径树问题,且其计算时间(迭代次数)仅正比于最短路径上的跃点数,与赋权图的复杂度、路径总长、边长的精度、通路总数等因素无关. 计算机仿真结果表明该算法的有效性和快速求解能力.
关键词:
单源最短路问题
自动波竞争神经网络
脉冲耦合神经网络 相似文献
102.
103.
M. Faber A. N. Ivanov N. I. Troitskaya 《International Journal of Theoretical Physics》2007,46(1):143-148
We evaluate the evolution operator Z
Reg(R
2,R
1) introduced by Diakonov and Petrov for the definition of the Wilson loop in terms of a path integral over gauge degrees of
freedom. We use the procedure suggested by Diakonov and Petrov (Physics Letters B
224 (1989) 131) and show that the evolution operator vanishes.
PACS numbers: 11.10.-z; 11.15.-q; 12.38.-t; 12.38.Aw; 12.90.+b. 相似文献
104.
105.
106.
107.
Liu Hui-jun 《Frontiers of Physics in China》2007,2(2):171-177
We review our density functional study of oxygen adsorption on the outer surface of 4 ? single-wall carbon nanotubes, which
have been recently synthesized using a templating method. The stability of these 4 ? tubes under ambient conditions is investigated
by the nudged elastic band technique and further confirmed by the experimentally measured Raman spectra. Different adsorption
pictures of singlet O2 could be used to select a single chirality from a mixture of these ultra-small radius tubes.
相似文献
108.
This study proposes a common path interference optical system for the measurement of refractive indices and thickness of uniaxial crystal material. The measurement system comprises an accurate Mach–Zehnder laser interferometer, a single-axis rotary stepping motor, and a computer. The laser interferometer is composed of a single-frequency He–Ne laser, two-beam splitters and two reflectors. The Mach–Zehnder laser interferometer measures the optical length difference by using its linear measurement accuracy. The proposed solution procedure enables both the refractive indices and the thickness of the optical waveplate to be obtained. The proposed design differs from conventional designs in that it does not use a heterodyne modulator with a lock-in technique. It is shown that the refractive indices and thickness of the tested optical elements can be measured rapidly and accurately. 相似文献
109.
The identification of tyre induced vehicle interior noise 总被引:2,自引:0,他引:2
Sound transmission into a vehicle is classified as either airborne or structure borne sound. From the point view of noise control, the reduction of noise transferred by different paths requires different solutions. Coherence function analysis is often used to identify transmission paths. However it can be difficult to separate the airborne from structure borne components. The principle of acoustic reciprocity offers a convenient method for overcoming this difficulty. The principal states that the transfer function between an acoustic volume velocity source and an acoustic receiver is independent of a reversal of the position of source and receiver. The work done on this study involves exciting a stationary tyre and measuring the surface velocity of the tyre at a number of discrete points. The acoustic transfer functions between each point on the tyre and a receiver point are measured reciprocally. Two sets of measurements are then combined to yield a measure of the sound pressure due to a point force on the tyre via the acoustic transmission path only. This technique also provides information on the relative contributions of various regions of the tyre wall to the resultant noise. Also the sound radiation characteristics, the horn effect, and resonance at the wheel housing are identified through the reciprocal measurement. 相似文献
110.
Marta Sanz-Solé 《Journal of Functional Analysis》2008,255(1):255-281
We consider a stochastic wave equation in space dimension three driven by a noise white in time and with an absolutely continuous correlation measure given by the product of a smooth function and a Riesz kernel. Let pt,x(y) be the density of the law of the solution u(t,x) of such an equation at points (t,x)∈]0,T]×R3. We prove that the mapping (t,x)?pt,x(y) owns the same regularity as the sample paths of the process {u(t,x),(t,x)∈]0,T]×R3} established in [R.C. Dalang, M. Sanz-Solé, Hölder-Sobolev regularity of the solution to the stochastic wave equation in dimension three, Mem. Amer. Math. Soc., in press]. The proof relies on Malliavin calculus and more explicitly, the integration by parts formula of [S. Watanabe, Lectures on Stochastic Differential Equations and Malliavin Calculus, Tata Inst. Fund. Res./Springer-Verlag, Bombay, 1984] and estimates derived from it. 相似文献