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LED密码算法是2011年提出的超轻量级密码算法,主要是为资源受限下物联网加密应用研发的.轻量级密码算法结构相对简单,更容易被旁路攻击成功.随机掩码是一种有效抗旁路攻击的方法,在深入LED密码算法结构研究的基础上,提出一种全随机掩码的LED密码算法CMLED.论述了CMLED算法的设计方法,从形式化方面给出了抗高阶旁路攻击选择掩码的原则.同时,对全随机掩码的CMLED与原始算法进行了硬件资源占用与加密效率对比,实验表明CMLED仍然可以高效地在智能卡上实现. 相似文献
24.
When an organisation chooses a system to make regular broadcasts to a changing user base, there is an inevitable trade off
between the number of keys a user must store and the number of keys used in the broadcast. The Complete Subtree and Subset
Difference Revocation Schemes were proposed as efficient solutions to this problem. However, all measurements of the broadcast
size have been in terms of upper bounds on the worst-case. Also, the bound on the latter scheme is only relevant for small
numbers of revoked users, despite the fact that both schemes allow any number of such users. Since the broadcast size can
be critical for limited memory devices, we aid comparative analysis of these important techniques by establishing the worst-case
broadcast size for both revocation schemes.
相似文献
25.
Jean-Sébastien Coron 《Designs, Codes and Cryptography》2009,50(1):115-133
The first practical identity based encryption (IBE) scheme was published by Boneh and Franklin at Crypto 2001, based on the
elliptic curve pairing. Since that time, many other IBE schemes have been published. In this paper, we describe a variant
of Boneh-Franklin with a tight reduction in the random oracle model. Our new scheme is quite efficient compared to existing
schemes; moreover, upgrading from Boneh-Franklin to our new scheme is straightforward.
相似文献
26.
Stephan Ramon Garcia 《Journal of Mathematical Analysis and Applications》2007,335(2):941-947
If C is a conjugation (an isometric, conjugate-linear involution) on a separable complex Hilbert space H, then T∈B(H) is called C-symmetric if T=CT∗C. In this note we prove that each C-symmetric contraction T is the mean of two C-symmetric unitary operators. We discuss several corollaries and an application to the Friedrichs operator of a planar domain. 相似文献
27.
针对传统的ElGamal加密机制不能抵抗自主选择密文攻击的问题,通过引入安全Hash函数和伪随机数发生函数给出了一种新的增强ElGamal加密机制.结果表明,该机制不仅能够抵抗自主选择密文攻击,且由于伪随机数发生函数的引入,解决了加密过程中随机数的暴露问题.该机制加密过程需要两次模幂运算,解密过程仅需一次模幂运算.完全适合于对安全性要求较高但是对系统资源要求消耗低的应用环境. 相似文献
28.
By using sequences generated from fractional-order hyperchaotic systems, a color image encryption scheme is investigated. Firstly, a plain image, which is known to users in advance, is chosen as a secret key to confuse the original image. Then, the confused image is encrypted by the sequences generated from the fractional-order hyperchaotic systems. With this simple encryption method, we can get an encrypted image that is fully scrambled and diused. For chaos-based image cryptosystems, this encryption scheme enhances the security and improves the eectiveness. Furthermore, the cryptosystem resists the dierential attack. Experiments show that the algorithm is suitable for image encryption, and some statistical tests are provided to show the high security in the end 相似文献
30.
《Communications in Nonlinear Science & Numerical Simulation》2014,19(10):3735-3744
This paper deals with a synchronization scheme for two fractional chaotic systems which is applied in image encryption. Based on Pecora and Carroll (PC) synchronization, fractional-order Lorenz-like system forms a master–slave configuration, and the sufficient conditions are derived to realize synchronization between these two systems via the Laplace transformation theory. An image encryption algorithm is introduced where the original image is encoded by a nonlinear function of a fractional chaotic state. Simulation results show that the original image is well masked in the cipher texts and recovered successfully through chaotic signals. Further, the cryptanalysis is conducted in detail through histogram, information entropy, key space and sensitivity to verify the high security. 相似文献