全文获取类型
收费全文 | 344篇 |
免费 | 15篇 |
国内免费 | 15篇 |
专业分类
化学 | 103篇 |
力学 | 4篇 |
数学 | 256篇 |
物理学 | 11篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 8篇 |
2017年 | 9篇 |
2016年 | 15篇 |
2015年 | 9篇 |
2014年 | 4篇 |
2013年 | 53篇 |
2012年 | 12篇 |
2011年 | 22篇 |
2010年 | 17篇 |
2009年 | 21篇 |
2008年 | 38篇 |
2007年 | 23篇 |
2006年 | 29篇 |
2005年 | 21篇 |
2004年 | 12篇 |
2003年 | 8篇 |
2002年 | 13篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 6篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1981年 | 2篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有374条查询结果,搜索用时 31 毫秒
41.
Donal O'Regan 《Journal of Mathematical Analysis and Applications》2006,324(2):1370-1380
In this paper we show that the solution set of certain Volterra inclusions defined between Fréchet spaces is a continuum. The proof relies on results in Banach spaces and on viewing a Fréchet space as a projective limit of a sequence of Banach spaces. 相似文献
42.
Donal O’Regan 《Rendiconti del Circolo Matematico di Palermo》2009,58(3):477-484
Several new fixed point results for permissible self extension type maps are presented in this paper. 相似文献
43.
The paper discusses the existence of positive solutions, dead core solutions and pseudodead core solutions of the singular
Dirichlet problem (ϕ(u′))′ = λf(t, u, u′), u(0) = u(T) = A. Here λ is the positive parameter, A > 0, f is singular at the value 0 of its first phase variable and may be singular at the value A of its first and at the value 0 of its second phase variable.
This work was supported by grant no. A100190703 of the Grant Agency of the Academy of Sciences of the Czech Republic and by
the Council of Czech Government MSM 6198959214. 相似文献
44.
We consider the following system of integral equations $${u_{i}(t)=\int\nolimits_{I} g_{i}(t, s)f(s, u_{1}(s), u_{2}(s), \cdots, u_{n}(s))ds, \quad t \in I, \ 1 \leq i\leq n}$$ where I is an interval of $\mathbb{R}$ . Our aim is to establish criteria such that the above system has a constant-sign periodic and almost periodic solution (u 1, u 2,…,u n ) when I is an infinite interval of $\mathbb{R}$ , and a constant-sign periodic solution when I is a finite interval of $\mathbb{R}$ . The above problem is also extended to that on $\mathbb{R}$ $$u_{i} {\left( t \right)} = {\int_\mathbb{R} {g_{i} {\left( {t,s} \right)}f_{i} {\left( {s,u_{1} {\left( s \right)},u_{2} {\left( s \right)}, \cdots ,u_{n} {\left( s \right)}} \right)}ds\quad t \in \mathbb{R},\quad 1 \leqslant i \leqslant n.} }$$ 相似文献
45.
Summary We discuss the existence or the existence and uniqueness of global and local -bounded variation (BV) solutions as well as continuous BV-solutions of nonlinear Hammerstein and Volterra-Hammerstein integral equations formulated in terms of the Lebesgue integral. Since the space of functions of bounded variation in the sense of Jordan is a proper subspace of functions of -bounded variation and for some class of functions , the space of functions of bounded -variation in the sense of Young is also a proper subspace of the space under consideration, our results extend known results in the literature. 相似文献
46.
Existence of Positive Solutions for Operator Equations and Applications to Semipositone Problems 总被引:2,自引:0,他引:2
In this paper we study the existence of positive solutions of the following operator equation in a Banach space E:
where G(x, λ) = λKFx+e0, K: E↦ E is a linear completely continuous operator, F: P↦ E is a nonlinear continuous , bounded operator, e0∈ E, λ is
a parameter and P is a cone of Banach space E. Since F is not assumed to be positive and e0 may be a negative element, the operator equation is a so-called semipositone problem. We prove that under certain super-linear
conditions on the operator F the operator equation has at least one positive solution for λ > 0 sufficiently small, and that under certain sub-linear
conditions on the operator F the operator equation has at least one positive solution for λ > 0 sufficiently large. In addition, we briefly outline an application of our results which simplify previous theorems in
the literature. 相似文献
47.
48.
We present a reasonable concept for solutions of non-instantaneous impulsive Cauchy problems with a ψ–Hilfer fractional derivative. Also, we provide a new sufficient condition for the existence, uniqueness, and stability of solutions for the given problem. 相似文献
49.
Yanan Zhao Xiaoying Zhang Donal O''Regan 《Journal of Applied Analysis & Computation》2019,9(6):2096-2110
We discuss the dynamic of a stochastic Susceptible-Infectious-Recovered-Susceptible (SIRS) epidemic model with nonlinear incidence rate.The crucial threshold $\tilde{R}_0$ is identified and this will determine the extinction and persistence of the epidemic when the noise is small. We also discuss the asymptotic behavior of the stochastic model around the endemic equilibrium of the corresponding deterministic system. When the noise is large, we find that a large noise intensity has the effect of suppressing the epidemic, so that it dies out. Finally, these results are illustrated by computer simulations. 相似文献
50.
We study existence and uniqueness of solutions for a general class of second order abstract differential equations with state-dependent delay. Some examples related to partial differential equations with state dependent delay are presented. 相似文献