全文获取类型
收费全文 | 118篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
化学 | 20篇 |
晶体学 | 1篇 |
力学 | 9篇 |
数学 | 71篇 |
物理学 | 7篇 |
无线电 | 12篇 |
出版年
2023年 | 1篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 6篇 |
2015年 | 2篇 |
2014年 | 12篇 |
2013年 | 16篇 |
2012年 | 3篇 |
2011年 | 3篇 |
2010年 | 5篇 |
2009年 | 9篇 |
2008年 | 4篇 |
2007年 | 6篇 |
2006年 | 6篇 |
2005年 | 5篇 |
2004年 | 3篇 |
2003年 | 7篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1991年 | 1篇 |
排序方式: 共有120条查询结果,搜索用时 0 毫秒
1.
We provide a rigorous derivation of an asymptotic formula for perturbations in the eigenvalues caused by the presence of a finite number of inhomogeneities of small diameter with conductivity different from the background conductivity. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
2.
Mohammed Boutayeb Soufiane El Imadi El Mokhtar Essassi Nour-Eddine Es-Safi Lahcen El Ammari 《合成通讯》2013,43(14):2130-2137
New pyrazolo[1.5.4-de]quinoxaline derivatives were prepared by the action of 7-aminoindazole 1 on diethyl and dimethyl acetylene dicarboxylates. The structures of the obtained compounds and the direction of cyclization were investigated through a crystallographic study of compound 2. Further alkylation, hydrogenation, and bromination were also explored. The action of potassium thiocyanate on the obtained halo product led to a tetracyclic compound of 1.3-thiazolo[3.4-a]pyrazolo[1.5.4-de]quinoxaline series. 相似文献
3.
Ben Haj Belkacem Oussama Ammari Mohamed Lassaad Bouallegue Ridha 《Wireless Personal Communications》2017,96(4):5587-5601
Wireless Personal Communications - This paper presents an analytical investigation on the effect of nonlinear high-power amplifiers on the physical layer security of multiple-input-multiple-output... 相似文献
4.
Habib Ammari Hyeonbae Kang Eunjoo Kim Hyundae Lee Kaouthar Louati 《Studies in Applied Mathematics》2009,122(1):85-104
The vibration behavior of structures can be characterized in terms of resonance frequencies and mode shapes, which describe properties of the tested object in a global way but do not, in general, provide information about structural details. Following an asymptotic formalism, in much the same spirit as the work in [ 3 ] and recent text [ 1 ], we develop an efficient method to address the inverse problem of identifying an internal corrosive part of small Hausdorff measure in a two-dimensional structure by vibration analysis. The viability of our reconstruction method is documented by a variety of numerical results from synthetic, noiseless and noisy data. 相似文献
5.
We establish an asymptotic expansion of the steady-state voltage potentials in the presence of a diametrically small conductivity inhomogeneity that is nearly touching the boundary. Our asymptotic formula extends those already derived for a small inhomogeneity far away from the boundary and is expected to lead to very effective algorithms, aimed at determining location and certain properties of the shape of a small inhomogeneity that is nearly touching the boundary based on boundary measurements. Viability of the asymptotic formula is documented by numerical examples. 相似文献
6.
7.
We consider the inverse problem of identifying locations and certain properties of the shapes of small elastic inclusions
in a homogeneous background medium from dynamic boundary measurements for a finite interval in time. Using particular background
solutions as weights, we present an asymptotic method based on appropriate averaging of the dynamic boundary measurements
and propose non-iterative algorithms for solving our inverse problem. 相似文献
8.
We consider for the inverse problem of identifying locations and certain properties of the shapes of small dielectric inhomogeneities in a homogeneous background medium from boundary measurements on part of the boundary or dynamic boundary measurements for a finite time interval. Using as weights particular background solutions we develop asymptotic methods based on appropriate averaging of the data. To cite this article: H. Ammari, A.G. Ramm, C. R. Mecanique 330 (2002) 199–205. 相似文献
9.
Adaptive modulation and decision feedback equalization for frequency‐selective MIMO channels 下载免费PDF全文
Mohamed Lassaad Ammari Kalthoum Zaouali Paul Fortier 《International Journal of Communication Systems》2014,27(11):3323-3338
In this paper, an adaptive modulation scheme for the multiple‐input multiple‐output (MIMO) frequency‐selective channels is investigated. We consider a scenario with precoded block‐based transceivers over spatially correlated Rayleigh multipath MIMO channels. To eliminate the inter‐block interference, the zero‐padding is used. The receiver is equipped with a MIMO minimum‐mean‐squared‐error decision feedback equalizer. The precoder aims to force each subchannel to have an identical signal‐to‐interference‐plus‐noise ratio (SINR). To adjust the constellation size, the unbiased mean square error at the equalizer output is sent back to the transmitter. To simplify our analysis, the feedback channel is considered as instantaneous and error free. We first derive the probability density function of the overall SINR for flat fading and frequency‐selective channels. On the basis of the probability density function of the upper bound of the SINR, we evaluate the system performance. We present accurate closed‐form expressions of the average spectral efficiency, the average bit error rate and the outage probability. The derived expressions are compared with Monte Carlo simulation results. Furthermore, we analyze the effect of the channel spatial correlation. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
10.
Habib Ammari Hyeonbae Kang Hyundae Lee Mikyoung Lim 《Communications in Mathematical Physics》2013,317(2):485-502
The aim of this paper is to extend the method of Ammari et al. (Commun. Math. Phys., 2012) to scattering problems. We construct very effective near-cloaking structures for the scattering problem at a fixed frequency. These new structures are, before using the transformation optics, layered structures and are designed so that their first scattering coefficients vanish. Inside the cloaking region, any target has near-zero scattering cross section for a band of frequencies. We analytically show that our new construction significantly enhances the cloaking effect for the Helmholtz equation. 相似文献