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71.
一类含时变分布时滞的退化中立型系统的鲁棒稳定性(英文) 总被引:1,自引:0,他引:1
考虑含分布时滞的退化中立型系统的鲁棒稳定性.利用算子Ω的稳定性和线性矩阵不等式得到一个新的鲁棒稳定性判据,本判据将中立型时滞、时变离散时滞、时变分布时滞和退化中立型系统一起考虑,相比已有文献具有较低的保守性.利用Matlab可以验证本判据的有效性. 相似文献
72.
73.
74.
Qu Chen Jiang-Hai Qian Liang Zhu Ding-Ding Han 《Journal of Applied Analysis & Computation》2016,6(1):30-37
We introduce temporal effect to the classical Kleinberg model and study how it affects the spatial structure of optimal transport network. The initial network is built from a regular $d$-dimensional lattice added by shortcuts with probability $p(r_{ij})\sim r_{ij}^{-\alpha} $ , where $r_{ij}$ is the geometric distance between node $i$ and $j$. By assigning each shortcut an energy $E=r \cdot \tau$, a link with length $r$ survives within period $\tau$,which leads the network to a decaying dynamics of constantly losing long-range links. We find new optimal transport in the dynamical system for $\alpha=\frac{3}{4}d$ , in contrast to any other result in static systems. The conclusion does not depend on the information
used for navigation, being based on local or global knowledge of the network, which indicates the possibility of the optimal design for general transport dynamics in the time-varying network. 相似文献
75.
This paper discusses the performance of controlled linear dynamic systems that use time-varying feedforward signals and time-varying linear-quadratic (LQ) feedback gains. Such a time-varying LQ controller can bring a dynamic system to a desired final state in roughly half the time required by a time-invariant LQ controller, since it pushes at both ends, i.e., it uses significant control effort near the end of the maneuver, as well as at the beginning, to meet the specified end conditions; there is no overshoot and no settling time. This requires a more complex controller and some care with the high gains near the final time. A MATLAB3 code is listed that synthesizes and simulates zero-order-hold time-varying LQ controllers. The precision landing of a helicopter using four controls is treated as an example. 相似文献
76.
In this paper, autocovariance nonstationary time series is clearly defined on a family of time series. We propose three types
of TVPAR (time-varying parameter auto-regressive) models: the full order TVPAR model, the time-unvarying order TVPAR model
and the time-varying order TVPAR model for autocovariance nonstationary time series. Related minimum AIC (Akaike information
criterion) estimations are carried out.
This work was supported by the Doctoral Research Fund of the Ministry of Education, China (Grant No. 20040285008), and Grant-in-Aid
for Scientific Research (B), the Ministry of Education, Science, Sports and Culture, Japan, 2005 (Grant No. 17300228) 相似文献
77.
This article presents an original method for evaluating thedissipative effect in SDOF systems due to the transient phenomenongenerated by time-varying forcing frequencies. The main contributionlies in the use of an event dimension, as additional dimension, andEinstein's method for highlighting and proving the existence of adamping term in the equation of the motion. The variational problem ofthe metric of a pseudo-Riemannian space gives the geodesic equations andthe equation of the motion. The application is concerned with aspring-pendulum system and the associated experimental investigationpermits validating the method proposed. The influence of the variationof the forcing frequency is highlighted using two different load cases:it is shown that the damping depends on the forcing frequency variation. 相似文献
78.
79.
In this paper, the problem of an exponential stability for time-delay systems with interval time-varying delays and nonlinear
perturbations is investigated. Based on the Lyapunov method, a new delay-dependent criterion for exponential stability is
established in terms of LMI (linear matrix inequalities). Numerical examples are carried out to support the effectiveness
of our results. 相似文献
80.
We study the properties of the tvGARCH(1, 1) model (1.8) with logistic coefficients. We obtain conditions for the existence
of an L
p
-bounded solution (p ⩾ 0) of Eq. (1.8). For p ⩾ 4, we prove an exponential decay of the lagged correlation function and the central limit theorem for partial sums of the
squared tvGARCH(1, 1) process under similar conditions as in the stationary case. In the second part of the paper, we study
the (weak) tail index of the tvGARCH(1, 1) model. 相似文献