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1.
Information‐Centric Networking (ICN) has been accepted to overcome some weaknesses of the current Internet architecture, showing that “what is being exchanged” is more important than “who are exchanging information.” Given the inadequate considerations on Quality of Service (QoS) and energy saving in ICN routing, we propose in this paper a routing algorithm to enhance the two aspects. At first, on one hand, Cauchy distribution is used as a fuzzy model to evaluate users' QoS requirements, such as bandwidth, delay, and error rate; on the other hand, we formulate energy saving problem to evaluate the green quality of routing algorithm. Then, we design a link selection approach by considering QoS and energy saving, which belongs to a multi‐objective decision problem resolved by intelligent drops algorithm. Finally, we implement the proposed algorithm and compare it with the famous adaptive forwarding mechanism in terms of some significant metrics, and the experimental results reveal that the proposed algorithm is more efficient.  相似文献   
2.
The piecewise linear method (PLM) based on time operator splitting is used to solve the unsteady compressible Euler equations describing the two-dimensional flow around and through a straight wall inlet placed stationary in a rapidly rotating supersonic flow. The PLM scheme is formulated as a Lagrangian step followed by an Eulerian remap. The inhomogeneous terms in the Euler equations written in cylindrical coordinates are first removed by Sod's method and the resulting set of equations is further reduced to two sets of one-dimensional Lagrangian equations, using time operator splitting. The numerically generated flow fields are presented for different values of the back pressure imposed at the downstream exit of the inlet nozzle. An oblique shock wave is formed in front of the almost whole portion of the inlet entrance, the incoming streamlines being deflected towards the higher pressure side after passing through the oblique shock wave and then bending down to the lower pressure side. A reverse flow appears inside the inlet nozzle owing to the recovery pressure of the incoming streams being lower than the back pressure of the inlet nozzle.  相似文献   
3.
We propose in this paper a self-organized monitoring architecture for mobile ad-hoc networks based on a selective scheme where subsets of nodes are managed. These nodes are determined based on their network behavior in order to favor subsets of well-connected nodes. The key idea is to relax the requirements of the management plane, and to use these manageable subsets to monitor the performance of the overall network. We therefore propose a new performance metric to be monitored, in order to estimate the capability of ad-hoc nodes to communicate end-to-end in the network. Extensive simulations show how different parameters affect this metric.  相似文献   
4.
Wireless ad hoc networks are temporary formed, infrastructureless networks. Due to the unstable channel conditions and network connectivity, their characteristics impose serious challenges in front of network designers. The layering approach to network design does not fit the ad hoc environment well. Therefore, various cross-layering approaches, where protocol layers actively interact, exchange inherent layer information and fine tune their parameters according to the network status are becoming increasingly popular. This paper presents an in-depth analysis of the latest cross-layering approaches for wireless ad hoc networks supported by several examples. A special emphasis is put on the link and network layer related cross-layer designs. Several link adaptation and efficient service discovery schemes are elaborated through analytical and simulation studies. Their performance shows the potentials of the cross-layering for boosting system characteristics in wireless ad hoc networks. Liljana Gavrilovska currently holds a position of full professor at Faculty of Electrical Engineering, University “St. Cyril and Metodij” – Skopje, Macedonia. She is chief of Telecommunications Laboratory and teaches undergraduate courses in telecommunication networks, data transmission and switching and traffic theory, and graduate courses in wireless, mobile and personal networks, teletraffic engineering and planning, and broadband multiservices networks. In 2000 she joined the Center for PersonKommunikation, Aalborg University, Denmark, as a visiting professor and during 2001--2002 she held a position of associate research professor at the same university. Currently she holds a part-time position of associated research professor with Center for Teleinfrastructur (CTIF). Prof. Gavrilovska was involved in several EU (ACTS ASAP, IST PACWOMAN, MAGNET, TEMPUS) and national/international projects. She published numerous conference and journal papers and participated in several workshops. At the moment she is working on the book “Ad Hoc Networking Towards Seamless Communications” together with prof. R. Prasad. Her research interests include wireless and personal area networks, ad hoc networking, networking protocols, traffic analysis, QoS, and optimization techniques. She is a senior member of IEEE and serves as a Chair of Macedonian Communication Chapter.  相似文献   
5.
To provide responsive information services in a ubiquitous computing environment, service software and system development are indispensable. A component-based ubiquitous information system with a JAIN (Java APIs for Integrated Networks) platform to achieve seamless transmissions and reach-everywhere communications was designed in our research. In this development, numerous ubiquitous service modules were identified: location management, roaming, mobile IP and WAP networking. These component-based network modules were constructed using a component composition language with component specification and interface definition, running on top of a distributed service architecture using a JAIN platform to distribute the ubiquitous information services to mobile users. Two applications, Wireless-Application-Protocol (WAP) Mail and Video-on-Demand (VoD) services, show that the JAIN-like platform with the developed networking components effectively fills the gap for application developers between mobile appliances and various kinds of ubiquitous information services.  相似文献   
6.
针对信息中心网络提供面向业务类型的差异化服务的问题,该文提出一种元模块承载的差异化服务模型(DSM3)。DSM3定义了基础网络控制功能单元元模块,通过匹配不同的元模块组合串实例来承载不同特征需求的业务类型;并将元模块组合过程视为业务策略实例组合串业务承载路径的二级映射问题,重点设计了针对实时业务、非实时流媒体业务和用户自产生业务的路由计算类元模块实例。仿真表明,DSM3通过少量额外控制开销,降低了上述3种业务的平均响应时延,提高了网络节点缓存命中率,实现了对于差异化服务需求的支持。  相似文献   
7.
战斗机航空电子系统最新的发展趋势-网络化   总被引:7,自引:3,他引:4  
梁德文 《电讯技术》2008,48(6):93-97
在分析未来战斗机面临的空中作战特点以及战斗机航空电子系统发展现状的基础上,根据未来信息化战争对航空电子系统发展需求的重大变化,提出未来战斗机航空电子系统在完成从"三代综合化"向"四代综合化"的转变以后,重点是朝着"网络化"方向发展的观点,并重点分析外军为实现这种网络化所采取的技术措施。  相似文献   
8.
针对物联传感网络由于数据类型不一致造成散粒噪声.提出一种物联传感网络散粒噪声过滤的自适应线性权值算法.提取物联传感网络散粒噪声特征参数,对上述参数进行线性变换,获取噪声关联特征参数自适应线性权值,完成物联传感网络散粒噪声过滤.实验表明,该算法能够有效过滤物联传感网络中的散粒噪声,取得了令人满意的结果.  相似文献   
9.
Although WeChat has recently spawned significant resolutions in technology-mediated social contact and interpersonal communication, the research regarding the social and psychological impacts of the newly emerging technology is relatively few. The primary purpose of the current empirical research is to unearth whether and how WeChat interaction could enhance overseas students’ sense of subjective well-being by concentrating on social integration, bridging relationships, and bonding relationships. Using web-based data of 228 Chinese subjects, the obtained results reveal that the time spent on WeChat significantly and directly impacts users’ subjective well-being. Additionally, the findings demonstrate that social integration, bridging relationships, bonding relationships are all significant predictors to subjective well-being. Furthermore, the perceptions of social integration and social capital could play the crucial mediating roles in the connection between WeChat use and the dependent variable of subjective well-being. Therefore, these outcomes may shed light on a more nuanced comprehending of the influence of the new social media interaction on sojourner’s social adaption and overall life quality in the digital age.  相似文献   
10.
An efficient disparity estimation algorithm for multi-view video sequences, recorded by a two-dimensional camera array in which the cameras are spaced equidistantly, is presented. Because of the strong geometrical relationship among views, the disparity vectors of a certain view can for most blocks be derived from the disparity vectors of other views. A frame constructed using that idea is called a D frame in this work. Three new prediction schemes which contain D frames are proposed for encoding 5 × 3 multi-view video sequences. The schemes are applied to several multi-view image sequences taken from a camera-array and they are compared in terms of quality, bit-rate and complexity. The experimental results show that the proposed prediction schemes significantly decrease the complexity of the encoder at a very low cost of quality and/or bit-rate.  相似文献   
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