25,155 research outputs found

    Solid state microelectronics tolerant to radiation and high temperature

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    The 300 C electronics technology based on JFET thick film hybrids was tested up to 10 to the 9th power rad gamma (Si) and 10 to the 15th power neutrons/sq cm. Circuits and individual components from this technology all survived this total dose although some devices required 1 hour of annealing at 200 or 300 C to regain functionality. This technology used with real time annealing should function to levels greater than 10 to the 10th power rad gamma and 10 to the 16th power n/sq cm

    Extreme distributions of ground winds /3 to 150 meters/ at Cape Kennedy, Florida

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    Statistical analysis of wind distribution probabilities at Cape Kenned

    Development of stitching reinforcement for transport wing panels

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    The NASA Advanced Composites Technology (ACT) program has the objective of providing the technology required to obtain the full benefit of weight savings and performance improvements offered by composite primary aircraft structures. Achieving the objective is dependent upon developing composite materials and structures which are damage tolerant and economical to manufacture. Researchers are investigating stitching reinforcement combined with resin transfer molding to produce materials meeting the ACT program objective. Research is aimed at materials, processes, and structural concepts for application in both transport wings and fuselages, but the emphasis to date has been on wing panels. Empirical guidelines are being established for stitching reinforcement in structures designed for heavy loads. Results are presented from evaluation tests investigating stitching types, threads, and density (penetrations per square inch). Tension strength, compression strength, and compression after impact data are reported

    6D Muon Ionization Cooling with an Inverse Cyclotron

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    A large admittance sector cyclotron filled with LiH wedges surrounded by helium or hydrogen gas is explored. Muons are cooled as they spiral adiabatically into a central swarm. As momentum approaches zero, the momentum spread also approaches zero. Long bunch trains coalesce. Energy loss is used to inject the muons into the outer rim of the cyclotron. The density of material in the cyclotron decreases adiabatically with radius. The sector cyclotron magnetic fields are transformed into an azimuthally symmetric magnetic bottle in the center. Helium gas is used to inhibit muonium formation by positive muons. Deuterium gas is used to allow captured negative muons to escape via the muon catalyzed fusion process. The presence of ionized gas in the center may automatically neutralize space charge. When a bunch train has coalesced into a central swarm, it is ejected axially with an electric kicker pulse.Comment: Five pages. LaTeX, three postscript figure files. To appear in the AIP Conference Proceedings for COOL05: International Workshop on Beam Cooling, Galena, IL, 18-23 Sept. 200

    Protein Supplementation as Related to Sources of Protein for Growing-Finishing Lambs

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    The objective of this study was to evaluate commercially available sources of supplemental protein in diets for growing and finishing lambs. Supplements were selected to differ in protein in diets for growing and finishing lambs. Supplements were selected to differ in protein solubility and amino acid profile and were expected to be degraded at different rates in the rumen to furnish protein post-ruminally varying in dietary and bacterial origin. If the principles concerning these parameters reported by other investigators would be applicable, response in terms of growth and feed utilization would be a measure of the value of the supplements for productive purposes

    A systems approach to the engineering workforce

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    The engineering function, work force and associations should be viewed as a system, for an adequate understanding of the complex interactions involved, for development of coherent policies and for achieving optimal overall performance. Such an approach embraces professional, para-professional and other categories, and requires a coherent system of qualifications, education, occupational identifiers and role definitions. For engineering education, it facilitates effective design of educational programs for each category and educational articulation between them. For industry and society, it fosters work force effectiveness and harmony. The paper provides the basis for systematising the complex of elements that make up the engineering system.<br /

    Proposal for an IMLS Collection Registry and Metadata Repository

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    The University of Illinois at Urbana-Champaign proposes to design, implement, and research a collection-level registry and item-level metadata repository service that will aggregate information about digital collections and items of digital content created using funds from Institute of Museum and Library Services (IMLS) National Leadership Grants. This work will be a collaboration by the University Library and the Graduate School of Library and Information Science. All extant digital collections initiated or augmented under IMLS aegis from 1998 through September 30, 2005 will be included in the proposed collection registry. Item-level metadata will be harvested from collections making such content available using the Open Archives Initiative Protocol for Metadata Harvesting (OAI PMH). As part of this work, project personnel, in cooperation with IMLS staff and grantees, will define and document appropriate metadata schemas, help create and maintain collection-level metadata records, assist in implementing OAI compliant metadata provider services for dissemination of item-level metadata records, and research potential benefits and issues associated with these activities. The immediate outcomes of this work will be the practical demonstration of technologies that have the potential to enhance the visibility of IMLS funded online exhibits and digital library collections and improve discoverability of items contained in these resources. Experience gained and research conducted during this project will make clearer both the costs and the potential benefits associated with such services. Metadata provider and harvesting service implementations will be appropriately instrumented (e.g., customized anonymous transaction logs, online questionnaires for targeted user groups, performance monitors). At the conclusion of this project we will submit a final report that discusses tasks performed and lessons learned, presents business plans for sustaining registry and repository services, enumerates and summarizes potential benefits of these services, and makes recommendations regarding future implementations of these and related intermediary and end user interoperability services by IMLS projects.unpublishednot peer reviewe

    The counter-streaming instability in dwarf ellipticals with off-center nuclei

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    n many nucleated dwarf elliptical galaxies (dE,N's), the nucleus is offset by a significant fraction of the scale radius with respect to the center of the outer isophotes. Using a high-resolution N-body simulation, we demonstrate that the nucleus can be driven off-center by the m=1 counterstreaming instability, which is strong in flattened stellar systems with zero rotation. The model develops a nuclear offset on the order of 30% of the exponential scale length. We compare our numerical results with the photometry and kinematics of FCC 046, a Fornax Cluster dE,N with a nucleus offset by 1.2" we find good agreement between the model and FCC 046. We also discuss mechanisms that may cause counterrotation in dE,N's and conclude that the destruction of box orbits in an initially triaxial galaxy is the most promising.Comment: 5 pages, 4 figure

    Precision metering of microliter volumes of biological fluids in micro-gravity

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    Concepts were demonstrated and investigated for transferring accurately known and reproducible microliter volumes of biological fluids from sample container onto dry chemistry slides in microgravity environment. Specific liquid transfer tip designs were compared. Information was obtained for design of a liquid sample handling system to enable clinical chemical analysis in microgravity. Disposable pipet tips and pipet devices that were designed to transfer microliter volumes of biological fluid from a (test tube) sample container in 1-G environment were used during microgravity periods of parabolic trajectories of the KC-135 aircraft. The transfer process was recorded using charge coupled device camera and video cassette equipment. Metering behavior of water, a synthetic aqueous protein solution, and anticoagulated human blood was compared. Transfer of these liquids to 2 substrate materials representative of rapidly wettable and slowly wettable dry chemistry slide surface was compared

    A Qualitative Study of the Initiation and Continuation of Preschool Inclusion Programs

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    This is the publisher's version, also found here: http://cec.metapress.com/content/h13780v85427/?p=7691ebee5d054406b7e2d78120f572db&pi=25Initiation and continuation of preschool inclusion is a challenging task. Through interviews and focus groups of school district and special education personnel, researchers in this study examined how 5 programs in 1 Midwestern state provided such services. The investigation used a multiple-case study methodology to examine how these programs initiated and sustained inclusive services. Especially important to these programs were factors such as having a shared vision, utilizing key personnel, and developing a structure within which the program could work. [ABSTRACT FROM AUTHOR
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