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41.
针对如何提高车辆自组织网络无线信道资源利用率问题,提出了一种分布式车辆间通信信道接入控制算法,该算法具体表示为利用中国余数定理设计一种用户保障协议序列,车辆节点(亦称用户)依据该协议序列决定其对通信信道的接入,无需基站或中心节点的协调,所设计的协议序列确保每个车辆节点在一个序列周期内至少成功发送一次数据.仿真结果表明,采用本文提出的协议序列控制算法比无反馈时隙ALOHA接入控制算法具有更小的传输时延,能够满足车辆自组织网络通信实时性的要求. 相似文献
42.
如何对已有的异构系统进行统一的用户及权限管理是军工行业在系统集成中的一个难点。分析了目前军工企业内部各应用系统分散式认证的种种弊端,利用单点登录技术构建了基于两级登录的身份认证框架,并对其中的关键技术进行了深入研究,最后将研究成果用于实际系统集成中,验证了其实用性和有效性。 相似文献
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44.
《Journal of Location Based Services》2013,7(3-4):141-178
ABSTRACTDisclosing the current location of a person can seriously affect their privacy, but many apps request location information to provide location-based services. Simultaneously, these apps provide only crude controls for location privacy settings (sharing all or nothing). There is an ongoing discussion about rights of users regarding their location privacy (e.g. in the context of the General Data Protection Regulation – GDPR). GDPR requires data collectors to notify users about data collection and to provide them with opt-out options. To address these requirements, we propose a set of user interface (UI) controls for fine-grained management of location privacy settings based on privacy theory (Westin), privacy by design principles and general UI design principles. The UI notifies users about the state of location data sharing and provides controls for adjusting location sharing preferences. It addresses three key issues: whom to share location with, when to share it, and where to share it. Results of a user study (N=23) indicate that (1) the proposed interface led to a greater sense of control, that (2) it was usable and well received, and that (3) participants were keen on using it in real life. Our findings can inform the development of interfaces to manage location privacy. 相似文献
45.
Jie Lian Yun Liu Zhen-Jiang Zhang Jun-Jun Cheng Fei Xiong 《电子科技学刊:英文版》2012,10(4):368-377
Based on user’s in-degree distribution, traditional ranking algorithms of user’s weight usually neglect the considerations of the differences among user’s followers and the features of user’s tweets. In order to analyze the factors which impact on user’s weight, under the analysis of the data collected from SINA Microblog network, this paper discovers that user influence and active degrees are the dominant factors for this issue. The proposed algorithm evaluates user influence by user’s follower number, the influence of user’s followers and the reciprocity between users. User’s active degree is modeled by user’s participation and the quality of user’s tweets. The models are tested by different data groups to confirm the parameters for the final calculation. Eventually, this paper compares the computational results with the user’s ranking order given by the SINA official application. The performance of this algorithm presents a stronger stability on the fluctuant range of the value of user’s weight. 相似文献
46.
移动网络中数据业务关键性能指标KPI探讨 总被引:1,自引:0,他引:1
移动网络的性能评估是网络规划和优化建设的前提,数据业务的迅速发展为移动网络的性能评估提出新的课题,当前评价数据业务网络的关键性能指标主要有吞吐量、时延等,从网络的容量和质量角度出发提出每用户平均吞吐量和网络资源利用率两个关键性能指标,并分别进行理论分析,为数据业务网络的性能评估提供参考依据。 相似文献
47.
介绍一种在乡镇有线电视网络单独经营核算环境下,县级广播电视系统利用宽带数据平台搭建有线电视用户信息集中管理和收视费银行代收的有线电视用户收费管理系统,该系统具有良好的扩展性,它的应用提高了用户管理人员的工作效率,提升了用户管理水平。 相似文献
48.
User Independent Paging Scheme for Mobile IP 总被引:1,自引:0,他引:1
Jiang Xie 《Wireless Networks》2006,12(2):145-158
Multi-step paging has been widely proposed in personal communications services (PCS) systems to reduce the signaling overheads.
Similar ideas can be applied to Mobile IP to provide IP paging services. However, current proposed multi-step paging schemes
are user dependent under which the partition of paging areas and the selection of paging sequence are different for each user.
The performance of a user dependent paging scheme for individual users may be affected by many factors. It is often difficult
to achieve perfect performance for each user. In addition, when multiple users are paged at the same time, user dependent
paging schemes may consume significant system resources. This paper introduces a user independent paging scheme where the
paging criterion is not based on individual user information. The goal of user independent paging is to provide satisfactory
overall performance of the whole system, when personalized optimal performance for each user is hard to obtain. The user independent
paging scheme is proposed for IP mobility for its easy implementation and convenient combination with paging request aggregation.
The paging criterion adopted is the mobility rate of each subnet determined by the aggregated movements of all mobile users.
In order to implement the proposed scheme, a concept of “semi-idle state” is introduced and the detailed solution for obtaining
mobility rate is presented. Analytical results show that when paging one user at a time, the performance of the proposed user
independent paging scheme is comparable to that of the paging schemes based on perfect knowledge of user movement statistics.
When paging multiple users simultaneously and when the knowledge on individual user behavior is not perfectly accurate, the
proposed scheme has remarkable advantages in terms of reducing the overall paging cost.
Jiang Xie received her B.E. degree from Tsinghua University, Beijing, China, in 1997, M.Phil. degree from Hong Kong University of Science
and Technology in 1999, and M.S. and Ph.D. degrees from Georgia Institute of Technology in 2002 and 2004, respectively, all
in electrical engineering. She is currently an assistant professor with the Department of Electrical and Computer Engineering
at the University of North Carolina-Charlotte. Her current research interests include resource and mobility management of
wireless networks,QoS provisioning, and next-generation Internet. She is a member of IEEE and ACM. 相似文献
49.
50.
基于嵌入式GUI雷达控制系统人机界面设计 总被引:1,自引:0,他引:1
将嵌入式图形用户界面(GUI)技术引入到现代雷达控制系统的人机界面设计中。分析了嵌入式GUI的技术特点和体系结构(包括配置、核心、色彩管理、字体、虚拟帧缓冲、事件驱动、窗口管理等模块),论述了采用这种技术的必要性与可行性,并以Qt/GUI为例,详细介绍了开发原理、步骤和方法。采用嵌入式GUI进行人机界面设计后,能够提高设备的开发效率、丰富人机交互信息。 相似文献