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121.
一种基于智能卡的双向身份认证方案 总被引:1,自引:0,他引:1
计算机网络的普及使更多的资源和应用可以利用网络远程获得,所以身份认证问题成为网络安全研究中的重要课题。当前主要的身份认证方法有以下几种:基于口令的身份认证;基于生物特征的身份认证;基于智能卡的身份认证以及几种方式的混合认证。结合密码学和智能卡技术的身份认证方案也被多次提出,许多专家和学者还提出了多种改进的方案。但是,这些方案均会出现一些不可避免的漏洞。针对多种方案的漏洞,该文提出了一种在智能卡中引入公钥密码算法的认证方案,并对其安全性进行了分析,该方案的安全性和优越性也在文中得到体现。 相似文献
122.
123.
In three‐party password‐based key exchange protocol, a client is allowed to share a human‐memorable password with a trusted server such that two clients can negotiate a session key to communicate with each other secretly. Recently, many three‐party password‐based key exchange protocols have been developed. However, these proposed schemes cannot simultaneously achieve security and efficiency. Based on elliptic curve cryptography (ECC), this paper will propose a new simple three‐party password‐based authenticated key exchange scheme. The proposed method not only reduces computation cost for remote users and a trusted server but also is more efficient than previously proposed schemes. It is better suited for resource constrained devices, such as smart cards or mobile units. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
124.
为了使计算机网络更好地为人类服务,必须很好地解决网络的信息安全问题。数字水印是实现版权保护的有效办法,但目前尚没有一个算法能够真正经得住攻击者所有种类的攻击。笔者通过对攻击原理进行分析,提出解决的对策,重点介绍了利用双水印技术对抗解释攻击的方法。了解这些攻击以及可能还会有的新的攻击方法将助于我们设计出更好的水印方案。 相似文献
125.
凌云 《微电子学与计算机》2011,28(9)
研究了网络抗攻击问题.针对网络节点在传输过程中,当在节点密钥没有及时、快速更新的情况下,网络节点会失去密钥保护,容易受到来自外部的攻击,造成网络安全隐患.文中提出了一种基于改进Feistel算法的数据加密技术.通过把传统的抗攻击密钥分成四个层次,层次之间相互关联,分层更新计算,使得网络节点密钥能够快速更新,加强网络安全性.实验结果表明,新算法在节点密钥更新速度上,大大加快,增加了网络节点的安全性,取得了很好的效果. 相似文献
126.
HUANG Jing-jing JIANG Ting 《中国邮电高校学报(英文版)》2014,21(5):76-82
The technology of 60 GHz radio is considered promising for providing fast connectivity and gigabit data rate. One of the main challenges to its secure indoor transmission is how to generate secret keys between communication devices. To investigate this issue, The authors develop an efficient mechanism of secret key generation exploiting multipath relative delay based on 60 GHz standard channel models. The comparison of key-mismatch probability between line-of-sight (LOS) and non-line-of-sight (NLOS) environments is considered. Verification of the proposed scheme is conducted. Simulation shows that the number of extracted multipath components proportionally did affect key generation rate and key-mismatch probability. It also indicates that communicating transceivers have a slightly lower key-mismatch probability in NLOS condition than in LOS condition. Moreover, in comparison to the existing approach of using received signal amplitude as a common random source, the mechanism can achieve better performance in key agreement. 相似文献
127.
针对人们对无线通信网络的功能和安全越来越高的要求,提出基于EC_DH交换密钥和基于RSA交换密钥的扩展WTLS(Wireless Transport Layer Security)协议。首先分析WAP安全架构中WTLS的安全性问题,然后根据数据的机密性、完整性以及在移动电话和其它无线终端中完成授权鉴定,在此基础上针对漏洞提出解决方案,改进后的协议增加了一个颁发证书的过程。最后通过案例证明本协议的安全性。结果表明,WTLS协议是一个更高安全性的协议,在无线通信网络中有着重要的价值和研究意义。 相似文献
128.
In this work cellulose acetate (CA) nanostructures were synthesized using electrospinning process. Silver nanoparticles (Ag NPs) were synthesized using silver nitrate as the starting precursor, ethanol as solvent and polyvinyl pyrolydone (PVP) as capping agent. The Ag NPs were added to the cellulose acetate (CA) nanostructures before and after CA electrospinning. The obtained CA and Ag-CA composite were characterized by various techniques such as, Fourier Transform Infrared (FTIR) spectroscopy, Raman Spectroscopy, Scanning electron microscopy (SEM) and Differential Scanning Calorimetry (DSC). It was found that Ag NPs can be effectively coated on or embedded into the electrospun CA and the PVP can lead to noticeable change in morphology and structure. 相似文献
129.
The emergence of quantum computer will threaten the security of existing public-key cryptosystems, including the Diffie Hellman key exchange protocol, encryption scheme and etc, and it makes the study of resistant quantum cryptography very urgent. This motivate us to design a new key exchange protocol and eneryption scheme in this paper. Firstly, some acknowledged mathematical problems was introduced, such as ergodic matrix problem and tensor decomposition problem, the two problems have been proved to NPC hard. From the computational complexity prospective, NPC problems have been considered that there is no polynomial-time quantum algorithm to solve them. From the algebraic structures prospective, non-commutative cryptography has been considered to resist quantum. The matrix and tensor operator we adopted also satisfied with this non-commutative algebraic structures, so they can be used as candidate problems for resisting quantum from perspective of computational complexity theory and algebraic structures. Secondly, a new problem was constructed based on the introduced problems in this paper, then a key exchange protocol and a public key encryption scheme were proposed based on it. Finally the security analysis, efficiency, recommended parameters, performance evaluation and etc. were also been given. The two schemes has the following characteristics, provable security,security bits can be scalable, to achieve high efficiency, quantum resistance, and etc. 相似文献
130.