Purpose of the Space Network Ground Segment Sustainment (SGSS) is to implement a new modern ground segment that will enable the NASA Space Network (SN) to deliver high quality services to the SN community for the future The key SGSS Goals: (1) Re-engineer the SN ground segment (2) Enable cost efficiencies in the operability and maintainability of the broader SN.

关键词：空间通信；地面支持系统；系统工程；系统兼容性

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The objective of this project is the extension of the Parallel Tools Platform (PTP) for applying it to peta-scale systems. PTP is an integrated development environment for parallel applications. It comprises code analysis, performance tuning, parallel debugging and system monitoring. The contribution of the ulich Supercomputing Centre (JSC) aims to provide a scalable solution for system monitoring of supercomputers. This includes the development of a new communication protocol for exchanging status data between the target remote system and the client running PTP. The communication has to work for high latency. PTP needs to be implemented robustly and should hide the complexity of the supercomputer's architecture in order to provide a transparent access to various remote systemerent systems, because PTP functions as abstraction layer between parallel application developer and compute resources. The common requirement for all PTP components is that they have to interact with the remote supercomputer. E.g. applications are built remotely and performance tools are attached to job submissions and their output data resides on the remote system. Status data has to be collected by evaluating outputs of the remote job scheduler and the parallel debugger needs to control an application executed on the supercomputer. The challenge is to provide this functionality for peta-scale systems in real-time.

关键词：电脑；并行处理器；计算机体系结构；计算机通讯

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Matrix multiplication is one of the most fundamental algorithmic problems in numerical linear algebra, distributed computing, scientific computing, and high-performance computing. Parallelization of matrix multiplication has been extensively studied (e.g., 21, 12, 24, 2, 51, 39, 36, 23, 45, 61). It has been addressed using many theoretical approaches, algorithmic tools, and software engineering methods in order to optimize performance and obtain faster and more efficient parallel algorithms and implementations. To design efficient parallel algorithms, it is necessary not only to load balance the computation, but also to minimize the time spent communicating between processors. The interprocessor communication costs are in many cases significantly higher than the computational costs. Moreover, hardware trends predict that more problems will become communication-bound in the future 38, 35. Even matrix multiplication, which is widely considered to be computation-bound, becomes communication-bound when a given problem is run on sufficiently many processors.

关键词：算法;分布式数据处理;软件工程;通信

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 Communication delays in distributed environments is an important and challenging problem that has not been adequately addressed. Communication delays are particularly insidious in air traffic control, and space and military operations, where communication and information sharing are paramount to team success. For the purposes of this research, we define communication delay as the time interval between a team member speaking a message (sender) and when another team member (recipient) hears it. The goal of this research is to better understand the effect of communication delays on team collaboration and team processes to maximize distributed team performance. This paper will explore the issue of communication delays in network-enabled environments, and describe an experiment developed to better understand the effects of communication delays on distributed team member trust, shared understanding, and satisfaction. Research questions are as follows: (1) What effect do audio communication delays have on distributed team trust, shared understanding (task accuracy), satisfaction, and cognitive workload; and (2) What effect does a video channel have on distributed team trust, satisfaction, and team member cognitive workload, when team member communication is delayed. For the purposes of this research, we will focus on synchronous audio and video communication technologies.

关键词：息交流；局域网；语音传输；通信网络

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Coordination with utility owners during the project development and delivery process involves multiple activities, such as requesting and collecting data about the location and characteristics of existing facilities to identifying and analyzing utility conflicts, coordinating with utility stakeholders for the resolution of those utility conflicts, preparing and executing utility agreements, coordinating and inspecting utility adjustments, and coordinating reimbursements and audits. Effective communication, cooperation, and coordination among utility stakeholders are critical to keeping transportation projects on schedule. Unfortunately, these elements are frequently lacking during project development and delivery to allow for the adoption of cost-effective solution strategies. This report documents the results of research completed to develop strategies to improve the participation and response of utility owners in the project development and delivery process. To achieve this objective, the researchers (1) reviewed strategies that the Texas Department of Transportation (TxDOT) and other agencies use to engage utility owners, (2) developed a set of strategies designed to optimize utility owner participation, (3) conducted stakeholder meetings and workshops to gauge the potential acceptability of these strategies, and (4) developed recommendations for changes to business processes and procedures. The four sets of strategies are: (1) modernization of the utility process, (2) utility conflict matrix approach, (3) streamlining and standardization of utility cost data submissions, and (4) core skill training on utility topics.

关键词：公用事业；权的方式（陆运）；冲突管理；交通运输系统

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This 2013 Measuring Broadband America February Report contains the most recent results from the Federal Communication Commissions (FCC) Measuring Broadband America program. This program, whose first results were published in August 2011, is an ongoing, rigorous, nationwide study of residential broadband performance in the United States. This study, like those conducted before, involves actual performance tests for thousands of subscribers of Internet Service Providers (ISPs) serving well over 80 percent of the residential market. Our initial Measuring Broadband America Report presented the first broad-scale study of actual consumer broadband performance throughout the United States. This effort was followed approximately a year later by a second report, released in July 2012, and now the present report. As explained in the accompanying Technical Appendix, each report in this series is based on measurements taken during a single reference month that has been chosen to represent a typical usage period for the average consumer. The reference month for the first report was March 2011, and the collection period for the second report, initially set for March 2011, was shifted to April 2012 to ensure collection of a sufficient amount of valid data. The reference month for this report is September 2012, five months after the previous testing period. As such, we present this as a supplemental report, noting that substantive network change is best measured in years, not months. Going forward, we plan to repeat testing each year in the month of September, and transition to annual reporting. In this report, we are pleased to include results on satellite technology for the first time, based on test results collected from ViaSat, a major satellite services provider. While in the past we have collected and released raw data on satellite performance, we have not reported on test results from this technology, as we recognized that the industry was on the verge of a major transition. In 2011, the satellite industry began launching a new generation of satellites offering performance as much as 100 times superior to the previous generation, leading to the entry of new satellite-based broadband providers. Consequently, we are now able to include comparisons between satellite and wireline technologies in this report.

关键词：电信；宽带；通信；互联网服务提供商（ISP）

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Traditional approaches to networking and security operate with static metrics and a black-and-white approach to decision-making. With the advent of network-centric environments and the emerging consideration of the impact of social networks on communications networks, we are forced to better understand how these additional factors can be used to improve networking services without assuming an unacceptable amount of risk. In this paper, we consider the implementation of trust metrics into various network protocols and security services. Our trust metric considers the impact of parameters of communication, information, and social networks. Using these parameters, we have developed composite trust metrics and applied them to the decision-making process within these protocols to replace the traditional approaches. The goal is to allow these trust-based protocols to operate in the gray area to improve performance and the range of operating conditions. We have studied tradeoffs between performance and security and trust and risk to identify optimal operating conditions of networks to maximize performance in several networking applications.

关键词：指挥和控制系统；通信网络；通信协议；计算机网络安全

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CO2 hydrogenation to olefins and ethylene oligomerization was investigated in efforts to improve catalyst composition and reaction conditions needed for scale-up. The hydrogenation of CO2 to hydrocarbons is investigated over -alumina-supported iron-based catalysts modified with manganese and potassium promoters and a silica-stabilized coating under fixed-bed reactor conditions to produce unsaturated hydrocarbons as feedstock chemicals for jet fuel synthesis. The stabilizer is introduced by impregnating the K/Mn/Fe on Al2O3 catalyst with tetraethylorthosilicate (TEOS) to minimize the deactivating effects of water on catalyst activity in CO2 hydrogenation. The K/Mn/Fe on Al2O3 catalyst modified with the TEOS and reduced in CO produced a lighter end fraction of olefins compared with the catalyst reduced in H2. To increase the chain length of the olefins formed in the CO2 hydrogenation step, investigation of oligomerization reaction is conducted in a separate experiment, where pure ethylene is used as a model olefin. Ethylene oligomerization over pelletized amorphous silica-alumina (ASA)-supported Ni catalysts demonstrated high conversion and selectivity towards the jet fuel fraction (C8-C16) at very low MHSV.

关键词：加氢；二氧化碳；氢；两步骤过程

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The Enhanced Cybersecurity Services (ECS) is a voluntary program based on the sharing of indicators of malicious cyber activity between Department of Homeland Security (DHS) and participating Commercial Service Providers. The purpose of the program is to assist the owners and operators of critical infrastructure to enhance the protection of their systems from unauthorized access, exploitation, or data exfiltration through a voluntary information sharing program. ECS consists of the operational processes and security oversight required to share unclassified and classified cyber threat indicators with companies that provide internet, network, and communication services to enable those companies to enhance their services to protect U.S. Critical Infrastructure entities. ECS is intended to support U.S. Critical Infrastructure, however, pending deployment of EINSTEIN intrusion prevention capabilities, ECS may also be used to provide equivalent protection to participating Federal civilian Executive Branch agencies. The National Protection and Programs Directorate (NPPD) is conducting this Privacy Impact Assessment (PIA) because personally identifiable information (PII) may be collected. This PIA consolidates and serves as a replacement to the DHS/NPPD/PIA-021 National Cyber Security Division Joint Cybersecurity Services Pilot PIA, published on January 13, 2012, and the DHS/NPPD/PIA-021(a) National Cyber Security Division Joint Cybersecurity Services Program (JCSP), Defense Industrial Base (DIB) Enhanced Cybersecurity Services (DECS) PIA Update, published on July 18, 2012.

关键词：电脑安全；隐私保护；计算机网络；通讯；信息安全

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We use x-ray spectroscopy and density functional theory to investigate the hydrogenation-induced electronic structure changes in graphene on Pt(111). The atom-specific properties of the spectroscopy allow for a direct projection of the band structure onto the carbon atoms; this was compared with the calculated density of states. Instead of the generally expected band opening behavior, we observe states at the Fermi level in the carbon-projected density of states. Hydrogenation is accompanied by pinning of the graphene to the substrate through the formation of local CPt bonds which cause the graphene layer to become metallic upon hydrogenation.

关键词：加氢；可逆；石墨烯

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