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所属行业:信息传输、软件和信息技术服务业

  • 36261.移动自组网的有效通讯:战术通信移动自组织网络路由方案的分析

    [信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-07-28]

    Warfighting based on Commander s Intent and Mission Tactics will remain the foundation of command and control, but the information structure that supports Marine Corps tactical units will continuously undergo changes based on developments in information technology. Mobile Ad Hoc Networking is one of the information technology developments that the Marine Corps is currently studying. Mobile Ad Hoc Network s (MANETs) are infrastructureless, highly mobile communications and their multi-hop routing capabilities have the potential to reliably and robustly extend existing networks to the tactical edge. There are many challenges to MANET implementation however, including management of the dynamic physical topology, and the efficient use of limited spectral and energy resources. One platform being tested by the Marine Corps utilizes a time-division multiple access (TDMA) scheme combined with Barrage Relaying to ensure robust communications. Other schemes for MANETs employ intelligent-routing protocols. This thesis examines those protocols and identifies the parameters needed to implement a tactical MANET routing scheme. The findings of this research advance understanding of MANETs and the elements necessary to enable their use in support of tactical communications; bringing the Marine Corps closer to its goal of lightweight and efficient tactical communications.
    关键词:网络;路由;战术通信;通信和无线电系统;基础(结构)
  • 36262.基于修正的背景加权直方图均值漂移和卡尔曼滤波的对象跟踪

    [信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-07-28]

    The classical mean shift (MS) algorithm is the best color-based method for object tracking.However,in the real environment it presents some limitations,especially under the presence of noise,objects with partial and full occlusions in complex environments.In order to deal with these problems,this paper proposes a reliable object tracking algorithm using corrected background-weighted histogram (CBWH) and the Kalman filter (KF) based on the MS method.The experimental results show that the proposed method is superior to the traditional MS tracking in the following aspects:1) it provides consistent object tracking throughout the video; 2) it is not influenced by the objects with partial and full occlusions; 3) it is less prone to the background clutter.
    关键词:目标跟踪;均值漂移;背景资料;卡尔曼滤波器;通信
  • 36263.QR分解与列主的避免通信排名揭示

    [信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-07-28]

    In this paper we introduce CARRQR, a communication avoiding rank revealing QR factorization with tournament pivoting. We show that CARRQR reveals the numerical rank of a matrix in an analogous way to QR factorization with column pivoting (QRCP). Although the upper bound of a quantity involved in the characterization of a rank revealing factorization is worse for CARRQR than for QRCP, our numerical experiments on a set of challenging matrices show that this upper bound is very pessimistic, and CARRQR is an effective tool in revealing the rank in practical problems. Our main motivation for introducing CARRQR is that it minimizes data transfer, modulo poly- logarithmic factors, on both sequential and parallel machines, while previous factorizations as QRCP are communication sub-optimal and require asymptotically more communication than CARRQR. Hence CARRQR is expected to have a better performance on current and future computers, where communication is a major bottleneck that highly impacts the performance of an algorithm.
    关键词:通信;数据传输;QR分解;通信优化算法
  • 36264.商用车安全应用的性能要求进展—最终报告201006-201103

    [计算机、通信和其他电子设备制造业,信息传输、软件和信息技术服务业] [2014-07-28]

    The U.S. Department of Transportation is conducting research to accelerate the widespread adoption of vehicle-to-vehicle (V2V) technology in commercial vehicles such as heavy trucks and buses. The widespread deployment of V2V safety is dependent on understanding the effectiveness of safety applications. The objective of this study was to determine the high-level performance requirements for potential V2V safety applications that are appropriate for commercial vehicles. This objective was accomplished via a 9-month project that involved reviewing literature covering collision avoidance systems currently available on heavy commercial vehicles, interviewing commercial vehicle industry representatives (manufacturers, suppliers, and fleet operators) to determine suitable crash avoidance technologies for the V2V communication, and identifying and developing high-level performance requirements for the selected commercial vehicle safety applications.
    关键词:通信;商业车辆安全;碰撞避免技术性能要求;防撞系统
  • 36265.无线电通信中继系统的进化

    [计算机、通信和其他电子设备制造业,信息传输、软件和信息技术服务业] [2014-07-28]

    Providing long-distance non-line-of-sight control for unmanned ground robots has long been recognized as a problem, considering the nature of the required high-bandwidth radio links. In the early 2000s, the DARPA Mobile Autonomous Robot Software (MARS) program funded the Space and Naval Warfare Systems Center (SSC) Pacific to demonstrate a capability for autonomous mobile communication relaying on a number of Pioneer laboratory robots. This effort also resulted in the development of ad hoc networking radios and software that were later leveraged in the development of a more practical and logistically simpler system, the Automatically Deployed Communication Relays (ADCR). Funded by the Joint Ground Robotics Enterprise and internally by SSC Pacific, several generations of ADCR systems introduced increasingly more capable hardware and software for automatic maintenance of communication links through deployment of static relay nodes from mobile robots. This capability was finally tapped in 2010 to fulfill an urgent need from theater. 243 kits of ruggedized, robot- deployable communication relays were produced and sent to Afghanistan to extend the range of EOD and tactical ground robots in 2012. This paper provides a summary of the evolution of the radio relay technology at SSC Pacific, and then focuses on the latest two stages, the Manually-Deployed Communication Relays and the latest effort to automate the deployment of these ruggedized and fielded relay nodes.
    关键词:无线电中继系统;通信和无线电系统;特设网状网络;无线电链路
  • 36266.驾车时使用的移动设备—美国和七个欧洲国家

    [信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-07-28]

    Road traffic crashes are a global public health problem, contributing to an estimated 1.3 million deaths annually (1). Known risk factors for road traffic crashes and related injuries and deaths include speed, alcohol, nonuse of restraints, and nonuse of helmets. More recently, driver distraction has become an emerging concern (2). To assess the prevalence of mobile device use while driving in Belgium, France, Germany, the Netherlands, Portugal, Spain, the United Kingdom (UK), and the United States, CDC analyzed data from the 2011 EuroPNStyles and HealthStyles surveys. Prevalence estimates for self-reported talking on a cell phone while driving and reading or sending text or e-mail messages while driving were calculated. This report describes the results of that analysis, which indicated that, among drivers ages 1864 years, the prevalence of talking on a cell phone while driving at least once in the past 30 days ranged from 21in the UK to 69in the United States, and the prevalence of drivers who had read or sent text or e-mail messages while driving at least once in the past 30 days ranged from 15in Spain to 31in Portugal and the United States. Lessons learned from successful road safety efforts aimed at reducing other risky driving behaviors, such as seat belt nonuse and alcohol-impaired driving, could be helpful to the United States and other countries in addressing this issue (2,3). Strategies such as legislation combined with high-visibility enforcement and public education campaigns deserve further research to determine their effectiveness in reducing mobile device use while driving. Additionally, the role of emerging vehicle and mobile communication technologies in reducing distracted drivingrelated crashes should be explored.
    关键词:移动设备;分心驾驶;交通事故;通信
  • 36267.混合DSRC-PCMS信息系统扫雪作业和施工区的发展

    [信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-07-28]

    Congestion and hazardous traffic situations for the drivers on the road can occur around work zones and snowplow operation during the winter season due to low visibility. An information warning system for such environments can improve traffic mobility and thereby driver safety. Intelligent transportation systems (ITS) and other related technologies are being aggressively pursued to devise such automated traffic-information systems. Dedicated short-range communication (DSRC) has been considered as a key enabling wireless communication technology to realize such automated traffic warning systems. DSRC-based traffic-information systems use vehicle-to-vehicle (V2V) and/or vehicle-to-infrastructure (V2I) communication using DSRC technology to acquire and disseminate travel safety information. To take advantage of the disseminated information messages, a vehicle needs to be equipped with DSRC technology.
    关键词:车安全;通信系统;信息系统;无线通信
  • 36268.应用纳米材料的分层问题的优化算法:最终技术报告(R.M.刘易斯)

    [其他制造业,信息传输、软件和信息技术服务业] [2014-07-28]

    The broad research objective of the overall project was the development of multi-scale optimization approaches to aid in the design of energy storage systems. More specically, we focused on the development of optimization methods that operate on different physical length-scales for optimizing the internal structure of nanoporous materials. Potential applications include electrical supercapacitors and hydrogen storage systems. The optimization algorithms we have developed can be applied to more general hierarchical design problems arising from the design of complex systems.
    关键词:储氢;纳米材料;分层问题;优化算法;技术报告
  • 36269.计算科学:蜻蜓密钥交换协议的安全性分析

    [信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-07-28]

    ragonfly is a password authenticated key exchange protocol that has been submitted to the Internet Engineering Task Force as a candidate standard for general internet use. We analyzed the security of this protocol and devised an attack that is capable of extracting both the session key and password from an honest party. This attack was then implemented and experiments were performed to determine the time-scale required to successfully complete the attack.
    关键词:数据处理;攻击;认证;通信协议
  • 36270.应用抽象的通信意图以提高便携性和生产力

    [信息传输、软件和信息技术服务业] [2014-07-28]

    Programming with communication libraries such as the Message Passing Interface (MPI) obscures the high-level intent of the communication in an application and makes static communication analysis difficult to do. Compilers are unaware of communication libraries’ specifics, leading to the exclusion of communication patterns from any automated analysis and optimizations. To overcome this, communication patterns can be expressed at higher-levels of abstraction and incrementally added to existing MPI applications. In this paper, we propose the use of directives to clearly express the communication intent of an application in a way that is not specific to a given communication library. Our communication directives allow programmers to express communication among processes in a portable way, giving hints to the compiler on regions of computations that can be overlapped with communication and relaxing communication constraints on the ordering, completion and synchronization of the communication imposed by specific libraries such as MPI. The directives can then be translated by the compiler into message passing calls that efficiently implement the intended pattern and be targeted to multiple communication libraries. Thus far, we have used the directives to express point-to-point communication patterns in C, C++ and Fortran applications, and have translated them to MPI and SHMEM.
    关键词:分布式数据处理;计算机通讯;编程语言;通信
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