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991.
基于Novozhilov理论连续弯箱位移参数的动态Bayes估计 总被引:2,自引:0,他引:2
推导了基于Novozhilov理论的简支弯箱有限曲条控制方程,并结合柔度法解决了连续弯箱的求解问题.建立了连续弯箱位移参数的动态Bayes误差函数,推导了相应的动态Bayes均值和方差表达式,提出步长的一维自动寻优方案后,结合共轭梯度法研究了连续弯箱位移参数的动态Bayes估计方法,同时给出了连续弯箱位移参数具体估计步骤.通过典型算例分析,总结了连续弯箱位移参数先验信息准确性判定方法及位移参数动态Bayes随机估计的其它重要结论. 相似文献
992.
一类热传导问题源项识别的快速稳定算法 总被引:1,自引:0,他引:1
利用正算子的性质和Lax-Milgram定理,将一维热传导方程源项识别问题转化为适定的、第二类Volterra方程的求解,给出一个新的快速稳定算法,并进行理论分析.采用两种实现后验准则的新途径,在输入数据的误差水平已知和未知的情况下,快速地决定正则参数.数值实验证实了算法的有效性. 相似文献
993.
The time domain parameter laenuncauon memoa oi me iounuauon-structure interaction system is presented. On the basis of building the computation mode and the motion equation of the foundation-structure interaction system, the system parameter identification method was established by using the extended Kalman filter (EKF) technique and taking the unknown parameters in the system as the augment state variables. And the time parameter identification process of the foundation-structure interaction system was implemented by using the data of the layer foundation-storehouse interaction system model test on the large vibration platform. The computation result shows that the established parameter identification method can induce good parameter estimation. 相似文献
994.
提出地基-结构相互作用系统的时域参数识别方法.在建立地基-结构相互作用的计算模式和运动方程的基础上,运用扩展的卡尔曼滤波技术,将相互作用系统中的参数作为增加的状态变量,建立了该系统的时域参数识别方法.并依据大型振动台条件下的层状地基-贮仓结构相互作用系统的模型试验数据,实施了地基-结构相互作用系统时域参数识别的全过程.计算结果表明,该方法产生良好的参数估计. 相似文献
995.
We study the quantum fluctuations of the charge and current of two L-C dissipative mesoscopic circuit with the mutual inductance in the vacuum state.Our results show that the system state will evolve to a squeezed coherent state under the effect of external source.We find that the squeezing amplitude parameter is relative to the parameters of circuit and the mutual-inductance coefficient in the existence of dissipation.When the circuit has no dissipation or there is complete coupling between two meshes,the squeezing amplitude parameter only depends on the capacitance‘s ratio. 相似文献
996.
ZHANG De-Hai 《理论物理通讯》2002,38(2):253-255
The evolution of the quintessence in various stages of the universe, i.e., the radiation-, matter-, and quintessence-dominated stages, is closely related with the tracking
behavior and the deceleration parameter of the universe. We gave the explicit relation between the equation-of-state of the quintessence in the epoch of the matter-quintessence equality and the
inverse power index of the quintessence potential, obtained the constraint
on this potential parameter coming from the present deceleration parameter,
i.e., a low inverse power index. We point out that the low inverse power-law
potential with a single term cannot work for the tracking solution. In
order to have both of the tracker and the suitable deceleration parameter it
is necessary to introduce at least two terms in the quintessence potential.
We give the future evolution of the quintessential universe. 相似文献
997.
IntroductionIn 1 990 ,Ott,GrebogiandYorke (OGY)introducedtheconceptofcontrolofchaosandgaveamethodforcontrollingchaos,knownastheOGYmethod[1].AfterOGY ,manyothermethodsforcontrollingchaoshavebeendeveloped[2 - 8].Otherrelatedtopics,suchasnoiseeffectsandoptimizationofthecontrol,havealsobeeninvestigated[9- 12 ].TheOGYmethodconsidersthemapξn+ 1=Fp(ξn) ,ξ∈R2 ,wherep∈Risaparameter,whichhasasaddleatacertainvalueoftheparameter.Thereforethereareaone_dimensionalstablemanifoldandaone_dimension… 相似文献
998.
Henning Fernau Rolf Niedermeier 《Journal of Algorithms in Cognition, Informatics and Logic》2001,38(2):374
The constraint bipartite vertex cover problem (CBVC for short) is as follows: given a bipartite graph G with n vertices and two positive integers k1, k2, is there a vertex cover taking at most k1 vertices from one and at most k2 vertices from the other vertex set of G? CBVC is NP-complete. It formalizes the spare allocation problem for reconfigurable arrays, an important problem from VLSI manufacturing. We provide a nontrivial so-called fixed parameter algorithm for CBVC, running in O(1.3999k1 + k2 + (k1 + k2)n) time. Our algorithm is efficient and practical for small values of k1 and k2, as occurring in applications. The analysis of the search tree is based on a novel bonus point system: after the processing of the search tree (which takes time exponential in k), a polynomial-time final analysis follows. Parts of the computation that would be normally done within the search-tree phase can be postponed; nevertheless, knowledge about the size of those parts can be used to reduce the length of the search paths (and hence the depth of the search tree as a whole) by a sort of bonus points. 相似文献
999.
The modelling of one kind of nonlinear parabolic distributed parameter control system with moving boundary, which had extensive
applications was presented. Two methods were used to investigate the basic characteristics of the system: 1) transforming
the system in the variable domain into that in the fixed domain; 2) transforming the distributed parameter system into the
lumped parameter system. It is found that there are two critical values for the control variable: the larger one determines
whether or not the boundary would move, while the smaller one determines whether or not the boundary would stop automatically.
For one-dimensional system of planar, cylindrical and spherical cases the definite solution problem can be expressed as a
unified form. By means of the computer simulation the open-loop control system and close-cycle feedback control system have
been investigated. Numerical results agree well with theoretical results. The computer simulation shows that the system is
well posed, stable, measurable and controllable.
Foundation item: the National Natural Science Foundation of China (59936140)
Biographies:ZHOU Jian-jun (1953-); XU Yan-hou (1933-) 相似文献
1000.