We conducted this review to determine the merits of an allegation that VA was transmitting sensitive data, including Personally Identifiable Information (PII) and internal network routing information, over unencrypted telecommunications carrier networks. The VA Midwest Health Care Network, also known as the Veterans Integrated Service Network (VISN) 23 within the Veterans Health Administration, serves more than 400,000 veterans enrolled to receive medical care residing in Iowa, Minnesota, Nebraska, North Dakota, South Dakota and portions of Illinois, Kansas, Missouri, Wisconsin, and Wyoming. In May 2012, a complainant contacted the VA Office of Inspector General (OIG) Hotline, alleging that certain VA medical centers (VAMCs) were transmitting sensitive information, including PII and internal network routing information, over unencrypted telecommunications carrier networks. More specifically, the complainant indicated that unencrypted data were transmitted among various VAMC networks using the South Dakota Network, which functions as the local telecommunications carrier network.The complainant alleged that these security violations occurred at VAMCs located in Fort Meade, SD; Omaha, NE; and Sioux Falls, SD, which are in VISN 23. To determine the merits of this Hotline allegation, we visited the three VAMCs identified in the complaint letter. We interviewed VA's Office of Information and Technology (OIT) personnel to gain an understanding of existing data transmission practices and associated controls.

关键词：退伍军人（军事人员）;通信网络;计算机通信;数据传输

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The integration of Unmanned Aircraft Systems (UAS) in the National Airspace represents new operational concepts required in civil aviation. These new concepts are evolving as the nation moves toward the Next Generation Air Transportation System (NextGen) under the leadership of the Joint Planning and Development Office (JPDO), and through ongoing work by the Federal Aviation Administration (FAA). The desire and ability to fly UAS in the National Air Space (NAS) in the near term has increased dramatically, and this multi-agency effort to develop and implement a national plan to successfully address the challenges of UAS access to the NAS in a safe and timely manner is well underway. As part of the effort to integrate UAS in the National Airspace, NASA Glenn Research Center is currently involved with providing research into Communications systems and Communication system operations in order to assist with developing requirements for this implementation. In order to provide data and information regarding communication systems performance that will be necessary, NASA GRC is tasked with developing and executing plans for simulations of candidate future UAS command and control communications, in line with architectures and communications technologies being developed and/or proposed by NASA and relevant aviation organizations (in particular, RTCA SC-203). The simulations and related analyses will provide insight into the ability of proposed communications technologies and system architectures to enable safe operation of UAS, meeting UAS in the NAS project goals (including performance requirements, scalability, and interoperability), and ultimately leading to a determination of the ability of NextGen communication systems to accommodate UAS. This presentation, compiled by the NASA GRC team, will provide a view of the overall planned simulation effort and objectives, a description of the simulation concept and status of the design and development that has occurred to date.

关键词：飞机通讯；通信网络；无线电通信；无人驾驶飞机系统

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The building blocks of emerging Petascale massively parallel processing (MPP) systems are multi-core processors with four or more cores as a single processing element and a customized network interface. The resulting memory and communication hierarchy of these platforms are now exposed to application developers and end users by creating a hierarchical or multi-core aware message-passing (MPI) programming interface and by providing a handful of runtime, tunable parameters that allows mapping and control of MPI tasks and message handling. We characterize performance of MPI communication patterns and present strategies for optimizing applications performance on Cray XT series systems that are composed of contemporary AMD processors and a proprietary network infrastructure. We highlight dependencies in its memory and network subsystems, which could influence production-level applications performance. We demonstrate that MPI micro-benchmarks could mislead an application developer or end user since these benchmarks often do not expose the interplay between memory allocation and usage in the user space, which depends on the number of tasks or cores and workload characteristics. Our studies show performance improvements compared to the default options for our target scientific benchmarks and production-level applications.

关键词：通信;并行编程;基准;通讯执行情况;内存

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Mobile devices have, in many ways, replaced traditional desktops in usability, usefulness, and availability. Improvements to computational power, battery life, device capabilities, and user experience will continue to drive people to stop using desktops and solely use mobile devices. Applications are vital to maximize usefulness of these devices. Development of these applications proceeds with a rapidity that surpasses the development pace of the devices themselves. Current methods are inadequate when attempting to verify and validate the behavior of the applications to ensure they perform correctly as the customer expect and correctly with respect to the software specifications. The current V&V methods are limited to environments that do not reflect the typical operational environment for mobile devices. These methods lead to false beliefs that the results of V&V tests prove correctness of the software, when they are only proving that the software works in a non-mobile environment. To solve this problem, we propose that application log files be used to capture the execution behavior while operating in their typical environment. The log file along with customer requirements, represented formally as statechart assertions, will provide a mechanism to conduct automated V&V on the behavior of the application while it was operating in its planned, mobile environment.

关键词：行为;移动通信系统;预期寿命（使用寿命）;验证

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The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCAN) Testbed on the International Space Station (ISS) will provide experimenters an opportunity to develop and demonstrate experimental waveforms in space. The GD SDR platform and initial waveform were characterized on the ground before launch and the data will be compared to the data that will be collected during on-orbit operations. A desired function of the SDR is to estimate the received signal to noise ratio (SNR), which would enable experimenters to better determine on-orbit link conditions. The GD SDR does not have an SNR estimator, but it does have an analog and a digital automatic gain control (AGC). The AGCs can be used to estimate the SDR input power which can be converted into a SNR. Tests were conducted to characterize the AGC response to changes in SDR input power and temperature. This purpose of this paper is to describe the tests that were conducted, discuss the results showing how the AGCs relate to the SDR input power, and provide recommendations for AGC testing and characterization.

关键词：自动增益控制;表征;无线电通信;空间通信;空间导航

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With a focus on complex environments,the present paper describes a new algorithm in scale changed object tracking through color feature.Mean shift (MS) iterative procedure is the best color-based algorithm to find the location of an object.The algorithm performance is not acceptable once tracking scale changed objects in complex environments.In this paper,the main aim is to improve the MS method,using corrected background-weighted histogram (CBWH) algorithm to reduce the interference of background in target localization.To fit the object scale change,the sum of gradient mode (SGM) is employed.The experimental results show that the proposed method is superior to the traditional mean shift tracking in the following aspects:1) it provides consistent object tracking throughout the video; 2) it is not influenced by the tracked objects scale changes; 3) it is less prone to the background clutter.

关键词：目标跟踪;均值漂移;背景资料;梯度模式的总和;通信

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To improve the efficiency of communications among unmanned systems, the research focused on the novel use of asymmetric polarized MIMO and network availability. The dissertation objective was to maintain the highest network availability for a mobile ad hoc network with heterogeneous communication capabilities. Using a hybrid dual-polarized Rayleigh fading channel model, asymmetric antenna configurations were studied in simulation for bit error rate and capacity. For a 1 x 1 configuration, polarization reciprocity was used to exploit the polarized channel knowledge, thereby maximizing received uplink power. The optimum gains to maximize uplink capacity were also derived for varying channel cross-polarization values. Larger configurations of 2 x 1 and 2 x 2 were investigated, including overlays of orthogonal space-time block coding, which improved diversity performance in the polarized channels. Extending these link results to realistic scenarios with unmanned systems, a reference point group mobility model including large-scale propagation was proposed to compute the network availability. Another scenario detailed robot exploration of unknown environments, which included large-scale path loss models. While deploying the network, the factors of exploration strategies, signal thresholds and routing were shown to impact the availability metric. Lastly, four extensible formation models were analyzed for their influence on network availability.

关键词：无线通信的天线配置;不对称；渠道；通信和无线电系统;配置;

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The indoor communications is a new market in the future.This Article introduces one data transmission system based with OFDM signals.The overview of the communication system and synchronization theory background will be introduced.The simulation results shown in this article implies that this OFDM system achieves excellent performance for indoor wireless communication.

关键词：室内无线通信；数据传输系统；OFDM；同步

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Mobile devices, such as smart phones and tablets, typically need to support multiple security objectives: confidentiality, integrity, and availability. To achieve these objectives, mobile devices should be secured against a variety of threats. The purpose of this publication is to help organizations centrally manage the security of mobile devices. Laptops are out of the scope of this publication, as are mobile devices with minimal computing capability, such as basic cell phones. This publication provides recommendations for selecting, implementing, and using centralized management technologies, and it explains the security concerns inherent in mobile device use and provides recommendations for securing mobile devices throughout their life cycles. The scope of this publication includes securing both organization-provided and personally-owned (bring your own device, BYOD) mobile devices.

关键词：信息安全；移动设备；管理计划和控制;可用性；通信安全

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Advancing technologies in smallsats provide remote sensing and communications capabilities achievable with a constellation of satellites at a reasonable cost to meet military needs. Like any other nation looking for a cheap but effective solution in that area, Turkey might also benefit from a replacement of its remote sensing assets. Currently, Turkish Armed Forces rely on a limited number of reconnaissance aircraft and Unmanned Aerial Vehicles, which do not provide real-time or near real-time remote sensing capabilities. Near real-time remote sensing needs for the Turkish warfighter dictates that the Turkish Armed Forces reach that capability as soon as possible. Likewise, replacing its conventional communication radios with satellite communication devices would also fulfill its warfighter needs. While current communication devices have physical limitations in Turkey's mountainous terrain and the surrounding seas, satellite communication capability would provide a wider coverage, and for specific frequencies, it might provide better resistance to jamming and interference. For the benefit of the Turkish Armed Forces' communications needs, a satellite constellation must be optimized such that effective coverage will be achieved with the least number of satellites to provide a reasonable cost. In this study, satellite constellation optimization for the Turkish Armed Forces will be achieved using Analytical Graphics, Inc.'s Systems Tool Kit software for simulation and analysis of several possible communications and remote sensing satellite constellations covering Turkish territory and surrounding seas. The Concept of Operations (CONOPS) for a smallsat constellation will be described and an optimized smallsat constellation will be modeled using STK software. The resulting data will be analyzed and discussed in the form of a recommendation that would benefit the Turkish Armed Forces.

关键词：通信；卫星通讯；计算机程序；计算机模拟

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