Communication, i.e., moving data, between levels of a memory hierarchy or between parallel processors on a network, can greatly dominate the cost of computation, so algorithms that minimize communication can run much faster (and use less energy) than algorithms that do not. Motivated by this, attainable communication lower bounds were established in [12, 13, 4] for a variety of algorithms including matrix computations.The resultapplies to recursive programs, irregular iteration spaces, sparse matrices, and other data structures as long asthe computation can be logically mapped to loops and indexed data structure accesses. We also discuss whenoptimal algorithms exist that attain the lower bounds; this leads to new asymptotically faster algorithms forseveral problems.

关键词：通讯；最优算法；程序；最小通信；矩阵乘法

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The Commissioninstituted this investigation on January 4, 2011, based on a complaint filed by Rambus Inc. of Sunnyvale, California (Rambus), alleging a violation of section 337 in the importation, sale for importation, and sale Withinthe United States after importation of certain semiconductor chips and products containing the same. 76 Fed. Reg. 384 (Jan. 4, 2011). The complaint alleged the infringement of various claims of patents including U.S. Patent Nos. 6,470,405; 6,591,353; 7,287,109 (collectively, the Barth patents); and Nos. 7,602,857; and 7,715,494 (collectively, the Dally patents). The Barth patents share a common specification, as do the Dally patents.

关键词：电子信息；半导体；芯片；产品

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This report covers work done for the Director's Research Initiative (DSI) on Gallium Nitride (GaN) High Power Electronics (HPE) in which GaN devices are assessed in comparison to those fabricated from silicon carbide (SiC). We show that for low power applications (less than 1500 V) GaN diodes should have a lower on-resistance, and therefore less loss, than their SiC counterparts because the critical breakdown field and electron mobility are larger. We expect this will also be true for HPE GaN high electron mobility transistors (HEMTs) compared to SiC metal-oxide-semiconductor field effect transistors (MOSFETs). Although a few GaN devices have been made that have properties that exceed those made from SiC, these devices cannot yet be manufactured. Our work suggests the dominant problem is contamination of the metal-organic chemical vapor deposition (MOCVD) films by the carbon in the trimethyl gallium (TMGa). We suggest a better alternative is to grow the films by hydride vapor phase epitaxy (HVPE), which requires that conducting GaN substrates be grown to reduce the on-resistance (RON-SP) for the back side diodes. We also show that dislocations appear to strongly affect diode properties such as the ideality factor, but their effect on the breakdown voltage appears to be a less significant problem than was previously thought.

关键词：电子信息；电子；氮化镓；晶体管；二级管

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This report summarizes general activity including updates to the National Cyber Awareness System in February 2012. It includes current activity updates, alerts, and bulletins, in addition to other newsworthy events or highlights.

关键词：电子信息；计算机；美国；总结

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This report summarizes general activity including updates to the National Cyber Awareness System in April 2012. It includes current activity updates, alerts, and bulletins, in addition to other newsworthy events or highlights.

关键词：电子信息；计算机；美国；总结

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This report summarizes general activity including updates to the National Cyber Alert System in January 2012. It includes current activity updates, technical and non-technical cyber security alerts, and cyber security bulletins, in addition to other newsworthy events or highlights.

关键词：电子信息；计算机；美国；总结

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This report summarizes general activity including updates to the National Cyber Awareness System in March 2012. It includes current activity updates, alerts, and bulletins, in addition to other newsworthy events or highlights.

关键词：电子信息；计算机；美国；总结

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In late August through mid-December 2010, the Census Bureau conducted a field test of new and revised content in the 2010 American Community Survey (ACS) Content Test. The results of that testing will determine the content to be incorporated into production ACS starting in 2013. Computer ownership and Internet subscription questions need to be added into the American Community Survey due to legislative changes. The Broadband Data Improvement Act requires that the Secretary of Commerce, in consultation with the Federal Communications Commission, expand the ACS to elicit information from residential households to determine whether they own or use computers at their address, whether they subscribe to an Internet service and, if so, whether they subscribe to dial-up or broadband Internet service at that address. The goal of this project is to evaluate the two versions of computer ownership and Internet subscription questions in the 2010 ACS Content Test to help determine which one will ultimately go into ACS production starting in 2013.

关键词：电子信息；计算机；互联网；内容评估

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This report summarizes general activity including updates to the National Cyber Awareness System in May 2012. It includes current activity updates, alerts, and bulletins, in addition to other newsworthy events or highlights.

关键词：电子信息；计算机；美国；总结

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The Simulation Interoperability Standards Organization (SISO) Smackdown is a two-year old annual event held at the 2012 Spring Simulation Interoperability Workshop (SIW). A primary objective of the Smackdown event is to provide college students with hands-on experience in developing distributed simulations using High Level Architecture (HLA). Participating for the second time, the University of Alabama in Huntsville (UAHuntsville) deployed four federates, two federates simulated a communications server and a lunar communications satellite with a radio. The other two federates generated 3D computer graphics displays for the communication satellite constellation and for the surface based lunar resupply mission. Using the Light-Weight Java Graphics Library, the satellite display federate presented a lunar-texture mapped sphere of the moon and four Telemetry Data Relay Satellites (TDRS), which received object attributes from the lunar communications satellite federate to drive their motion. The surface mission display federate was an enhanced version of the federate developed by ForwardSim, Inc. for the 2011 Smackdown simulation. Enhancements included a dead-reckoning algorithm and a visual indication of which communication satellite was in line of sight of Hadley Rille. This paper concentrates on these two federates by describing the functions, algorithms, HLA object attributes received from other federates, development experiences and recommendations for future, participating Smackdown teams.

关键词：电子信息；计算机；三维；攻击波

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