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51.
The computational Grid is currently gaining in popularity, and it enables computers scattered all over the world to be connected
by the Internet as if they are part of a large computational infrastructure. While the computational Grid gathers more and
more computational resources and the number of the applications for the computational Grid is increasing, load balancing for
the computational Grid is still not effective enough. Because the computers are connected by a wide area network on the computational
Grid, the significant communication latency and the frequency of large wave throughputs make it difficult to achieve effective
load balancing. Thus, in this paper, we propose an algorithm to predict networking loads on the computational Grid to make
the use of computational resources more efficient. The proposed algorithm based on the Markov model is evaluated using an
actual networking load. As a result, the Markov model based algorithm offers the most accurate predictions compared with the
related work.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
52.
树上秘密共享体制的信息率 总被引:1,自引:0,他引:1
研究以树G为通道结构的秘密共享体制的最优信息率ρ(G)。得到了ρ(G)=2/3的要条件。证明了ρ(G)不会介于实数区间(3/5,2/3)中,给出了以树G的阶数表示的ρ(G)的下界,求出两类具有某种结构的树的最优信息率。 相似文献
53.
This paper addresses the problem of routing and wavelength assignment of bit-rate-differentiated optical services in a hybrid network. Hybrid optical networks are composed of resources, such as fiber links and photonic/electronic switches, that vary in their capabilities and transmission qualities. These networks are also responsible for the realization of optical services with varying quality-of-service (QoS) guarantees. In such networks, it is required to have a cost-effective assignment of the optical and electronic resources to these services in order to maximize the revenue of the network operator. This paper deals with optical services that are defined according to their tolerance to transmission impairments. We first divide the provisioning problem into two phases: (1) routing and (2) wavelength assignment and regeneration reservation. In the routing phase, a set of k-routes are generated to select from in the second phase, where each route optimizes a specific aspect of the problem (e.g., number of hops, maximum accumulated noise, etc.). The second phase, using the information about the resources along each route, attempts at finding the best wavelength allocation on that route such that the signal quality meets the service-level agreement (SLA). The second phase also uses the minimum number of regenerator ports on intermediate nodes for the purpose of wavelength translation and signal clean-up. Comparisons of the above scheme with a probing-based method, reveal substantial enhancements to the blocking performance with a maximum running time increase of 60%. In addition, the use of multiple routes provides higher reduction in the blocking probability over single-routing schemes. Moreover, the proposed, non-pessimistic, provisioning approach has a major impact on reducing the regeneration budget of the network. 相似文献
54.
Mobile Commerce: Framework,Applications and Networking Support 总被引:16,自引:2,他引:14
Advances in e-commerce have resulted in significant progress towards strategies, requirements, and development of e-commerce applications. However, nearly all e-commerce applications envisioned and developed so far assume fixed or stationary users with wired infrastructure. We envision many new e-commerce applications that will be possible and significantly benefit from emerging wireless and mobile networks. To allow designers, developers, and researchers to strategize and create mobile commerce applications, we propose a four-level integrated framework for mobile commerce. Since there are potentially an unlimited number of mobile commerce applications, we attempt to identify several important classes of applications such as mobile financial applications, mobile inventory management, proactive service management, product location and search, and wireless re-engineering. We discuss how to successfully define, architect, and implement the necessary hardware/software infrastructure in support of mobile commerce. Also, to make mobile commerce applications a reality, we address networking requirements, discuss support from wireless carriers, and present some open research problems. 相似文献
55.
内容中心网络作为一种新型的未来网络体系架构被提出,以满足当前互联网信息共享的需求。内容中心网络使用类似域名的层次化名字结构对内容进行标识、路由和查找。由于互联网中内容众多,使用名字前缀构建的路由表,比传统的IP路由表大2~5个数量级,且由于名字查找依旧遵循最长前缀匹配原则,使得实现高速名字查找是一个富有挑战性的难题。分析了名字查找的技术挑战、实施难点,介绍了主要技术方法以及当前在名字查找领域的主要研究成果。 相似文献
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Jiann‐Liang Chen Shih‐Wei Liu Szu‐Lin Wu Ming‐Chiao Chen 《International Journal of Communication Systems》2011,24(9):1150-1162
Owing to limited wireless network resources, network applications must provide an adaptive quality‐guaranteed service to satisfy user requirements. Different applications are associated with different quality of service (QoS) concerns, as well as different QoS control parameters. This work presents an adaptive QoS algorithm by discussing the QoS specifications of three wireless access technologies, i.e. 3G, WiMAX and WiFi. Based on cross‐layer and cognition concepts, these environmental parameters are integrated with the sensing of spectral and received signal strength from a cognitive radio paradigm. An adaptive QoS algorithm is then proposed to select the optimal access network for services. Simulation results indicate that the proposed adaptive QoS algorithm outperforms available ones in real‐time applications. Compared with traditional algorithms, the proposed algorithm reduces not only the average delay time and jitter for VoIP services to 0.16 s and 0.09 ms, respectively, but also the packet loss ratio for high‐definition video streaming by 3.4%. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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