This report describes an engineering project for the preparation of test and analysis plans for selected mechanical components. The test plans are designed to provide data useful for the reliability prediction of mechanical components during the design phase of a system.

关键词：机械基础件；机械组件；工程项目测试与分析

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Due to the uniquely harsh lunar surface environment, terrestrial test activities may not adequately represent abrasive wear by lunar dust likely to be experienced in mechanical systems used in lunar exploration. Testing to identify potential moving mechanism problems has recently begun within the NASA Engineering and Safety Center Mechanical Systems Lunar Dust Assessment activity in coordination with the Exploration Technology and Development Program Dust Management Project, and these complimentary efforts will be described. Specific concerns about differences between simulant and lunar dust, and procedures for mechanical component testing with lunar simulant will be considered. In preparing for long term operations within a dusty lunar environment, the three fundamental approaches to keeping mechanical equipment functioning are dust avoidance, dust removal, and dust tolerance, with some combination of the three likely to be found in most engineering designs. Methods to exclude dust from contact with mechanical components would constitute mitigation by dust avoidance, so testing seals for dust exclusion efficacy as a function of particle size provides useful information for mechanism design. Dust of particle size less than a micron is not well documented for impact on lunar mechanical components. Therefore, creating a standardized lunar dust simulant in the particulate size range of ca. 0.1 to 1.0 micrometer is useful for testing effects on mechanical components such as bearings, gears, seals, bushings, and other moving mechanical assemblies. Approaching actual wear testing of mechanical components, it is beneficial to first establish relative wear rates caused by dust on commonly used mechanical component materials. The wear mode due to dust within mechanical components, such as abrasion caused by dust in grease(s), needs to be considered, as well as the effects of vacuum, lunar thermal cycle, and electrostatics on wear rate.

关键词：机械基础件；机械组件；月球表面

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To achieve the goal of the proposal, we created nano-structured surfaces to increase the pixel density and hence resolution of the opto- electronic sensor array by a factor of 3 in each direction, x and y. The proof of concept of this mathematical framework in the visible part of the optical spectrum was published in 2 journal articles (both published in Applied Physics Letters). In addition to this, we also experimentally applied the same concept to IR part of the optical spectrum and thus demonstrated the feasibility of our approach for IR focal plane arrays. these results will be presented at SPIE Defense, Security and Sensing Conference in April 2012.

关键词：传感器；红外探测器；光电；算法；数字系统；焦平面阵列的高分辨率；数学计算；纳米结构；成像；共振的金属亚波长孔；更高分辨率的传感器阵列

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An electric current sensor based on Faraday rotation effect in optical fiber was developedfor measuring aircraft lightning current. Compared to traditional sensors, the design hasmany advantages including the ability to measure total current and to conform to structuregeometries. The sensor is also small, light weight, non-conducting, safe from interference,and free of hysteresis and saturation. Potential applications include characterization oflightning current waveforms, parameters and paths, and providing environmental data foraircraft certifications. In an optical fiber as the sensing medium, light polarization rotateswhen exposed to a magnetic field in the direction of light propagation. By forming closedfiber loops around a conductor and applying Ampere’s law, measuring the total lightrotation yields the enclosed current. A reflective polarimetric scheme is used, wherepolarization change is measured after the polarized light travels round-trip through the sensing fiber. The sensor system was evaluated measuring rocket-triggered lightning overthe 2011 summer. Early results compared very well against a reference current shuntresistor, demonstrating the sensor’s accuracy and feasibility in a lightning environment.While later comparisons show gradually increasing amplitude deviations for anundetermined cause, the overall waveforms still compared very well.

关键词：传感器；光纤传感器

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The report was prepared for the International Energy Agency (IEA) Hydrogen Program and represents the result of subtask C, Annex 10 - Photoproduction of Hydrogen. The concept of using solar energy to drive the conversion of water into hydrogen and oxygen has been examined, from the standpoints of potential and ideal efficiencies, measurement of (and how to calculate) solar hydrogen production efficiencies, a survey of the state-of-the-art, and a technological assessment of various solar hydrogen options. The analysis demonstrates that the ideal limit of the conversion efficiency for 1 sun irradiance is (approximately)31for a single photosystem scheme and (approximately)42for a dual photosystem scheme. However, practical considerations indicate that real efficiencies will not likely exceed (approximately)10and (approximately)16for single and dual photosystem schemes, respectively. Four types of solar photochemical hydrogen systems have been identified: photochemical systems, semiconductor systems, photobiological systems, and hybrid and other systems.

关键词：太阳能；制氢；氢光电化学电池；光伏电池

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This guide helps you get started with a typical run of the Windows? OS Preparation V1 Script Package and defines the requirements of this automation in IBM? PureApplication? System.

关键词：PureApplication；IBM模式实验室；Windows操作系统；脚本包V1

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This project assessed the biomedical and toxicological literature for evidence of hormesis, its frequency in the literature and its underlying mechanistic foundation. This work was supported by the continued development of the hormesis database and the conduct of a high level international conference on hormesis held annually. Particular focus was given to the area of neuroscience and hormesis in the literature assessment. Fourteen manuscripts concerning hormesis and neuroscience have been accepted for publication in the journal Critical Reviews in Toxicology and will be published in 2008.

关键词：生物医药；辐射；数据库

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Technoeconomic work for IH2 and lifecycle analysis(LCA) work has also been completed as part of this DOE study and shows IH2 technology can convert biomass to gasoline and diesel blending components for less than $2.00/gallon with greater than 90reduction in greenhouse gas. As a result of the work completed in this DOE project, a joint development agreement with CRI Catalyst Company to license the IH2 technology.

关键词：生物质；汽油柴油；加氢燃料；温室气体；氢气加氢裂解；石油运输燃料

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The response of anisotropic pigment particle suspensions to externally applied electric fields has been explored for possible application in reflective display technologies. Three different types of pigment particle were suspended in dodecane using a polymeric stabiliser and showed Schlieren textures between crossed polarisers at high concentrations (>25-30 wt%), indicating the formation of colloidal nematic phases. Orientational order parameters were determined by X-ray scattering and the influence of polydispersity on the values is discussed. X-ray scattering measurements also demonstrated a change in the structure factor consistent with the onset of a colloidal nematic phase. In addition, the pigment particles were dispersed into various liquid crystal hosts at low concentrations (<5 wt%) with and without the presence of mesogenic mimic stabilisers. However, the influence of these stabilisers on orientational ordering could not be confirmed. The electro-induced ordering determined via scattering was related to the electro-optical response of each suspension using a simple model. The particles in nematic hosts showed a high degree of orientational ordering at lower electric field strengths but also showed a reduction in stability. Although these systems have shown strong orientational ordering, the optical response has been limited by the intrinsic shape of the pigment particles and the distribution of the transition dipoles moments within them. Nevertheless, the feasibility of developing materials for display applications has been demonstrated.

关键词：各向异性颜料纳米粒子；胶体；液晶；X射线散射；电场对齐

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We have designed computer memories that can shift a long user-specified contiguous region a short, fixed distance in constant time. Such memories make possible complementary co-designed software that not only improves performance but also simplifies and unifies solutions to fundamental computing problems including sorting, searching, and data management.

关键词：内存；软件；数据管理

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