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4881.姿态的氩的相对导航传感器套件在模拟飞行条件下的测量性能
[计算机、通信和其他电子设备制造业,铁路、船舶、航空航天和其他运输设备制造业] [2013-12-21]
Argon is a flight-ready sensor suite with two visual cameras, a flash LIDAR, an on- board flight computer, and associated electronics. Argon was designed to provide sensing capabilities for relative navigation during proximity, rendezvous, and docking operations between spacecraft. A rigorous ground test campaign assessed the performance capability of the Argon navigation suite to measure the relative pose of high-fidelity satellite mock-ups during a variety of simulated rendezvous and proximity maneuvers facilitated by robot manipulators in a variety of lighting conditions representative of the orbital environment. A brief description of the Argon suite and test setup are given as well as an analysis of the performance of the system in simulated proximity and rendezvous operations.
关键词:传感器;计算机;飞行控制;导航仪器;航天器
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4882.用ApacheThrift简化可扩展的云软件开发
[信息传输、软件和信息技术服务业] [2013-12-21]
Apache Thrift is a framework that enables scalable cross-language development, resulting in unambiguous communication among components in cloud environments. This article introduces the ideas around Thrift (an interface definition for remote procedure call with multilanguage bindings), and then demonstrates Thrift in a multilanguage client and server application.
关键词:Apache Thrift;云环境;可伸缩性
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4883.交通能源未来系列:预计生物质能将作为燃料和能源利用在一个成熟的市场。
[电力、热力、燃气及水生产和供应业] [2013-12-21]
The viability of biomass as transportation fuel depends upon the allocation of limited resources for fuel, power, and products. By focusing on mature markets, this report identifies how biomass is projected to be most economically used in the long term and the implications for greenhouse gas(GHG) emissions and petroleum use.
关键词:生物质能;燃料;交通运输;替代燃料;经济分析;能源需求;燃油消耗,温室效应;石油
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4884.玻璃:旧材料制造业的未来
[非金属矿物制品业,计算机、通信和其他电子设备制造业] [2013-12-21]
Traditional assembly line manufacturing is speculative, costly and environmentally unsustainable. It is speculative because it commits substantial resources—energy, materials, shipping, handling, stocking and displaying—without a guaranteed sale. It is costly because each of these resources—material, process, people and place—involves expense not encountered when a product is manufactured at the time of sale. It is environmentally unsustainable because, no matter how much recycling is done, not using the resources unless actually needed is always a better path. Three-dimensional printing is currently of great commercial interest as it can be employed to manufacture parts on-demand economically and without the significant cost & environmental downsides, i.e. inventory and waste, associated with traditional manufacturing processes. Herein, we describe the formulation of a novel water-based material which can be used in a traditional 3D printer extrusion process to create optically transparent glass-based objects. Such objects have a wide range of applications including, but not wholly limited to: security printing using color & coating effects, protective films and coatings, electronic codes readable by smartphones, tablets or touch screens. Additional all glass objects traditionally manufactured by the so called kiln glass method can be generated by this type of 3D printing making it interesting for the high end market of art objects.
关键词:胶体;挤压;3D打印
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4885.在PureApplication系统部署脚本包的IBM模式实验室快速入门指南:安装微软DynamicsCRMv2011
[信息传输、软件和信息技术服务业] [2013-12-21]
This guide gets you started with a typical installation for Microsoft? Dynamics? CRM v2011 using a script package and defines the requirements of this automation in IBM? PureApplication? System.
关键词:脚本包;Dynamics CRM v2011;IBM模式实验室
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4886.泛型编程中不应使用锁的原因
[信息传输、软件和信息技术服务业] [2013-12-21]
Locks are the most widely used synchronization mechanism for threads. It is well-known that naive use of locks can easily lead to program failures through deadlock. Such deadlock is usually avoided through careful lock ordering. We argue that this approach is incompatible with several increasingly important programming practices that rely on libraries invoking ("calling-back") essentially unknown client code. Template-based generic programming in C++ is probably the most extreme in its use of call-backs, in that often almost every operator used in a generic function is potentially defined by client code. Template functions are essential to C++. Much of the standard library consists of template functions and classes. We expect the same to be increasingly true for libraries designed for concurrency that support synchronization. We argue that if locks are used for synchronization in such code we have no reliable methodology for avoiding deadlock; we need an alternate synchronization mechanism. We argue that transactional memory can extract us from this predicament. Unlike much of the debate surrounding transactional memory, we do not start with a focus on performance. We argue instead that transactional memory provides a desperately needed programmability improvement, which we have learned how to implement with sufficient performance to make it viable.
关键词:锁;互斥;泛型编程;模板;事务内存;僵局
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4887.MEMS真空电场传感器的表征技术
[电气机械和器材制造业,计算机、通信和其他电子设备制造业] [2013-12-21]
An accurate calibration of an electric-field sensor is difficult to carry out due to challenges involved in generating a uniform electric field over the sensor volume. Additionally, capacitive coupling between the field source and the sensors and related instrumentation tends to distort the measured field further. Sensor characterization includes not only calibration, but also determination of the frequency response (both magnitude and phase), noise power spectral density, dynamic range, and linearity. In this paper, we discuss characterization techniques for an unpackaged microelectromechanical systems (MEMS) electric field sensor in a vacuum chamber. The use of oppositely charged square plates at a spacing of half the plate width is advised by the IEEE 1308-1994 standard for generation of a uniform electric field. Previously, the U.S. Army Research Laboratory (ARL) has shown that by employing guard tubes in the construction of an electric field generating chamber, the fringing fields can be controlled, and the spacing between the endplates can be increased while maintaining a uniform field. A similar, smaller apparatus for generating a uniform axial electric field was constructed to fit into a vacuum bell jar. The considerations and techniques for minimizing error due to fringing and distortion from metal conductors will be presented, along with the techniques and laboratory equipment used for characterizing the sensor.
关键词:传感器;电气领域;探测器;微机电系统;真空
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4888.自旋的进动有机磁性传感器
[电气机械和器材制造业,计算机、通信和其他电子设备制造业] [2013-12-21]
SRI International, in collaboration with Professor Jing Shih of the University of California-Riverside (UCR), Professor Nathan Newman of Arizona State University (ASU), and Professor Edmond Nowak of the University of Delaware (UD), has been funded (from June 2009 through September 2012) through ONR Contract (N00014-09-C-0292) to fabricate a magnetic sensor with a half-metallic ferromagnet (FM) contact and polymers and demonstrate its sensing capability. In this study we considered La0.7Sr0..3MnO3 (LSMO) and CoFe50Al25Si25 (CFAS) alloys for half-metallic FM contacts and poly(3,4-ethylenedioxythiophene) (PEDOT ) and poly- 3(hexylthiophene) (P3HT) for polymers. Room temperature operation of this ultrasensitive device requires half-metallic ferromagnetic contacts with high Curie temperature (Tc), ultra-lowmobility polymer with very high doping density, nano-scale trenches, successful charge and spin injection into polymers from FM half-metal contacts, and spin precession in polymers. The FM films for vertical and lateral devices were grown at UCR and ASU, respectively. Most device fabrication was carried out at SRI, while magnetic and noise measurements were performed at ASU and UD.
关键词:传感器;磁探测器
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4889.生物医学工程中心研究年报,第2卷
[医药制造业] [2013-12-21]
The Center for Biomedical Engineering Research, CBER, is an interdisciplinary center whose mission is to provide engineering science and clinical technology to reduce the impact of disease on the everyday life of individuals. It was created to provide an appropriate forum and infrastructure to promote the interaction of biomedical researchers from the university and the medical community. As such, CBER serves as a research umbrella under which investigators from a variety of fields can work together.
关键词:生物医药;医学研究;临床医学
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4890.一种混合页面布局百富集成和NSM
[信息传输、软件和信息技术服务业] [2013-12-21]
Prior work on in-page record formats has contrasted the "N-ary storage model" (NSM) and the "partition attributes across" (PAX) format. The former is the traditional standard page layout whereas the latter "exhibits superior cache and memory bandwidth utilization" [ADH 01], e.g., in data warehouse queries with large scans. Unfortunately, space management within each page is more complex due to the mini-pages in the PAX layout. "Borrowing" space from one mini-page for another requires moving an entire mini-page. In contrast, the NSM format simply grows a slot array and the data space from opposite ends of the page until all space is occupied. The present paper explores a hybrid page layout (HPL) that aims to combine the advantages of NSM and PAX. Predicate evaluation in large scan queries have the same number of cache faults as PAX, and space management uses two data areas growing towards each other. Moreover, the design defines a continuum between NSM and PAX in order to support both efficient scans and efficient insertions and updates. This design is equally applicable to cache lines within RAM memory (the original design goal of PAX) and to small pages on flash storage within large disk pages. Our experimental evaluation is based on an implementation in the former environment. It demonstrates that the HPL design scans almost as fast as the scan-optimized PAX layout and updates almost as fast as the update-optimized NSM layout, i.e., it is competitive with both in their best use cases.
关键词:数据库;存储管理器;百富;NSM;混合页面布局(HPL);页面布局