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41.
Y. Liu D. Lin C. Cheng H. Chen T. Jiang 《International Journal of Communication Systems》2014,27(11):3223-3231
In 2009, Lee and Chang proposed an electronic t‐out‐of‐n lottery protocol over the Internet based on the Chinese remainder theorem and blind signature. However, a security flaw exists in Lee–Chang's protocol that the lottery agent and the malicious purchaser can collude to control the winning result, which is unfair for the honest participants. On the basis of a verifiable random number generated by using the Lagrange interpolation formula over a finite field, an improved t‐out‐of‐n e‐lottery protocol is proposed, which guarantees that each participant can generate the winning result equally. The improved protocol achieves public verifiability and fairness without a trusted third party and a delaying function, which makes it more robust and more efficient. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
42.
基于Dempster-Shafer证据理论的信任评估模型 总被引:8,自引:0,他引:8
从网格的动态性、分布性、不确定性等特征出发,参考社会学的人际信任关系结构,提出了一种基于Dempster-Shafer证据理论(简称D-S理论)的信任评估模型.该模型根据网格节点间的历史交易记录,给出“直接信任”的形式化描述,建立网格节点信任推荐机制,并利用D-S理论对证据进行组合,从而得到“间接信任”.然后将直接信任和间接信任进一步组合为“综合信任”,从而有效实现信任信息的融合.将本文提出的信任度评估方法应用到调度算法中,结果证明了该信任模型的可行性和实用性. 相似文献
43.
蔡东汉 《武汉大学学报(理学版)》1998,(1)
得到一个具有可解内生人口出生率的Cass-Koopmans经济增长模型.给出此模型在不同劳动和资本的结合方式下存在唯一最优增长轨道和稳态解的条件.最后讨论存在多重最优增长轨道和多重稳态解的可能性态和文中主要结果的经济意义. 相似文献
44.
和叶肉相比,叶肉原生质体的K含量下降,Fe, Zn, Mn, Cu等元素的含量则显著升高,游离ABA水平显著较高;碱性过氧化物酶活性明显下降.以上事实表明,叶肉细胞的脱壁措施会使细胞原生质体的生理、、生化状况产生显著变化. 相似文献
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人工免疫系统方法中的否定选择(NS)算法已广泛应用于病毒防护、入侵检测、垃圾邮件检测等.然而,由于当前的计算机中不存在类似\"免疫器官\"的硬件部件,无法对NS算法的运行提供保护,可能造成其运行过程遭受恶意干扰,成熟检测器和中间变量遭受篡改,进而导致其检测结果不可信.借鉴自然免疫系统的组成和原理,提出一种基于可信根的计算机终端免疫模型(TRBCTIM),引入可信计算技术中的可信根作为\"免疫器官\",对NS算法实施保护.采用无干扰可信模型理论对新模型进行分析,并通过构建新模型的原型系统来进行性能实验.理论分析及实验结果表明,新模型能够确保NS算法的运行过程和检测结果可信. 相似文献
48.
Liquan Chen Ziyan Zhang Mengnan Zhao Kunliang Yu Suhui Liu 《Entropy (Basel, Switzerland)》2022,24(11)
As the foundation of quantum secure communication, the quantum key distribution (QKD) network is impossible to construct by using the operation mechanism of traditional networks. In the meantime, most of the existing QKD network routing schemes do not fit some specific quantum key practicality scenarios. Aiming at the special scenario of high concurrency and large differences in application requirements, we propose a new quantum key distribution network routing scheme based on application priority ranking (APR-QKDN). Firstly, the proposed APR-QKDN scheme comprehensively uses the application’s priority, the total amount of key requirements, and the key update rate for prioritizing a large number of concurrent requests. The resource utilization and service efficiency of the network are improved by adjusting the processing order of requests. Secondly, the queuing strategy of the request comprehensively considers the current network resource situation. This means the same key request may adopt different evaluation strategies based on different network resource environments. Finally, the performance of the APR-QKDN routing scheme is compared with the existing schemes through simulation experiments. The results show that the success rate of application key requests of the APR-QKDN routing scheme is improved by at least 5% in the scenario of high concurrency. 相似文献
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Since the guarantee of trustiness is considered inadequate in traditional software development methods, software developed using these methods lacks effective measures for ensuring its trustiness. Combining agent technique with the support of trusted computing provided by TPM, a trust shell based constitution model of trusted software (TSCMTS) is demonstrated, trust shell ensures the trustiness of software logically. The concept of Trust Engine is proposed, which extends the “chain of trust” of TCG into application, and cooperates with TPM to perform integrity measurement for software entity to ensure the static trustiness; Data Structure called trust view is defined to represent the characteristic of software behavior. For the purpose of improving the accuracy of trustiness constraints, a strategy for determining the weights of characteristic attributes based on information entropy is proposed. Simulation experiments illustrate that the trustiness of software developed by the TSCMTS is improved effectively without performance degradation. 相似文献