全文获取类型
收费全文 | 170篇 |
免费 | 5篇 |
专业分类
化学 | 40篇 |
晶体学 | 2篇 |
力学 | 15篇 |
数学 | 83篇 |
物理学 | 35篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2016年 | 6篇 |
2015年 | 10篇 |
2014年 | 10篇 |
2013年 | 11篇 |
2012年 | 7篇 |
2011年 | 10篇 |
2010年 | 10篇 |
2009年 | 9篇 |
2008年 | 6篇 |
2007年 | 8篇 |
2006年 | 9篇 |
2005年 | 6篇 |
2004年 | 5篇 |
2003年 | 5篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有175条查询结果,搜索用时 46 毫秒
1.
This paper proposes a perturbation-based heuristic for the capacitated multisource Weber problem. This procedure is based on an effective use of borderline customers. Several implementations are considered and the two most appropriate are then computationally enhanced by using a reduced neighbourhood when solving the transportation problem. Computational results are presented using data sets from the literature, originally used for the uncapacitated case, with encouraging results. 相似文献
2.
Barbu Vlad Stefan Beltaief Slim Pergamenchtchikov Serguei 《Annals of the Institute of Statistical Mathematics》2022,74(5):925-955
Annals of the Institute of Statistical Mathematics - In this paper we study generalized semi-Markov high dimension regression models in continuous time, observed at fixed discrete time moments. The... 相似文献
3.
Barbu Vlad Stefan Beltaief Slim Pergamenshchikov Sergey 《Statistical Inference for Stochastic Processes》2019,22(2):187-231
Statistical Inference for Stochastic Processes - We consider the nonparametric robust estimation problem for regression models in continuous time with semi-Markov noises. An adaptive model... 相似文献
4.
5.
Jamil Salhi James MacLaurin Salwa Toumi 《Stochastics An International Journal of Probability and Stochastic Processes》2018,90(1):49-60
In this paper we obtain a time-uniform propagation estimate for a system of interacting diffusion processes. Using a well defined metric function h , our result guarantees a time-uniform estimate for the convergence of a class of interacting stochastic differential equations towards their mean field limit, under conditions that ensure that the decay associated to the internal dynamics term dominates the interaction and noise terms. Our result should have diverse applications, particularly in neuroscience, and allows for models more elaborate than the one of Wilson and Cowan. In particular, the internal dynamics need not be that of linear decay. 相似文献
6.
Nesrine Mechi Ismahen Ben Khemis Houcine Dhaou Slim Zghal Abdelmottaleb Ben Lamine 《Chinese Journal of Physics (Taipei)》2018,56(2):449-467
The Mg50Ni45Cr5 alloy for hydrogen storage is prepared by mechanical alloying. First, using the X-ray diffraction (XRD) and the scanning electron microscopy (SEM) we examine the morphology and the structure of the substrate. The obtained results highlight the effectiveness of this alloy in loading hydrogen as it is a nanocrystalline and a ductile one. Second, we attempt to justify these expectations using the statistical physic, precisely the model monolayer with two levels of energy, in modeling a hydrogen absorption and desorption isotherms on Mg50Ni45Cr5 alloy at four temperatures T?=?275?K, T?=?300?K, T?=?325?K and T?=?350?K. The model has six physicochemical parameters deduced from the fitting of the isotherms, they are divided by two categories of steric and energetic parameters. Thanks to these parameters we compare the absorption and desorption processes, in order to highlight the hysteresis phenomenon encountered during the hydrogen sorption. 相似文献
7.
Well-known as a hazardous compound, nitrite constitute a real threat to the public health. So, there is a pressing need to detect and quantify them in different matrix. Even though conventional analytical methods can be used to address this issue, electrochemistry allows a fast, sensitive, and efficient analysis. Conducting polymers continue to raise great interest among scientific communities due to their properties. Moreover, their combination with carbon nanomaterials, or metallic nanoparticles improves their properties, and provides great results. In this paper, we will focus on some revealing works devoted to the electrochemical detection of nitrite using this kind of materials. 相似文献
8.
The concept of ‘nested methods’ is adopted to solve the location-routeing problem. Unlike the sequential and iterative approaches, in this method we treat the routeing element as a sub-problem within the larger problem of location. Efficient techniques that take into account the above concept and which use a neighbourhood structure inspired from computational geometry are presented. A simple version of tabu search is also embedded into our methods to improve the solutions further. Computational testing is carried out on five sets of problems of 400 customers with five levels of depot fixed costs, and the results obtained are encouraging. 相似文献
9.
H.A. Slim 《Nuclear Physics B》1981,177(1):172-188
Using the ansatz of Delbourgo and Salam for the vertex function in quantum electrodynamics, we find approximations to the spectral functions of the electron propagator for covariant gauges. The consistency with the integral relations for the change of the exact spectral functions under covariant gauge transformations is investigated. The approximated spectral functions appear not to be gauge covariant in general. 相似文献
10.
B. Ortaç A. Hideur M. Brunel T. Chartier M. Salhi H. Leblond F. Sanchez 《Applied physics. B, Lasers and optics》2003,77(6-7):589-594
The properties of an ytterbium-doped double-clad fiber laser, passively mode-locked by nonlinear polarization rotation are investigated in this work. Cartographies of mode-locking regime versus halfwave plates orientations are presented for several values of the total cavity dispersion and for different pump powers. Bistability between the continuous and the mode-locking regimes is pointed out. The effect of the total group velocity dispersion is described with a master mode-locking equation. PACS 42.55.Wd; 42.65.Re 相似文献