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Impedance calculation for ferrite inserts

Description: Passive ferrite inserts were used to compensate the space charge impedance in high intensity space charge dominated accelerators. They study the narrowband longitudinal impedance of these ferrite inserts. they find that the shunt impedance and the quality factor for ferrite inserts are inversely proportional to the imaginary part of the permeability of ferrite materials. They also provide a recipe for attaining a truly passive space charge impedance compensation and avoiding narrowband microwave instabilities.
Date: January 1, 2005
Creator: Breitzmann, S. C.; Lee, S. Y. & Ng, K. Y.
Partner: UNT Libraries Government Documents Department
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Design and Experimental Results for the S825 Airfoil; Period of Performance: 1998-1999

Description: A 17%-thick, natural-laminar-flow airfoil, the S825, for the 75% blade radial station of 20- to 40-meter, variable-speed and variable-pitch (toward feather), horizontal-axis wind turbines has been designed and analyzed theoretically and verified experimentally in the NASA Langley Low-Turbulence Pressure Tunnel. The two primary objectives of high maximum lift, relatively insensitive to roughness and low-profile drag have been achieved. The airfoil exhibits a rapid, trailing-edge stall, which does not meet the design goal of a docile stall. The constraints on the pitching moment and the airfoil thickness have been satisfied. Comparisons of the theoretical and experimental results generally show good agreement.
Date: January 1, 2005
Creator: Somers, D. M.
Partner: UNT Libraries Government Documents Department
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Final Report Providing the Design for Low-Cost Wireless Current Transducer and Electric Power Sensor Prototype

Description: This report describes the design and development of a wireless current transducer and electric power sensor prototype. The report includes annotated schematics of the power sensor circuitry and the printed circuit board. The application program used to illustrate the functionality of the wireless sensors is described in this document as well.
Date: January 31, 2005
Creator: Kintner-Meyer, Michael CW; Burghard, Brion J. & Reid, Larry D.
Partner: UNT Libraries Government Documents Department
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Designer Nanocellular Materials for Laser Targets and Other DNT Applications

Description: Overview. This document and the accompanying manuscripts summarize the technical accomplishments of our one-year LDRD-ER effort, a project that has since been incorporated into a larger LDRD-SI for FY05. The objective of this effort was to develop a predictive synthetic capability for the preparation of materials with cellular architectures (sub-micron pore or cell sizes and relative densities less than 10% of full density) not attainable by conventional methods. The ability to reliably prepare these nanocellular materials and control their bulk physical properties (e.g. mechanical strength) would be a considerable advance in the areas of porous materials and its impact would cut across many existing LLNL investments. One significant area related to the Laboratory mission that would benefit is the design of new materials for high energy density physics (HEDP) targets. Current synthetic techniques do not allow for the preparation of foams that meet all of the current and projected compositional and mechanical requirements of these experiments. This project focused on two main types of materials: inorganic sol-gel materials and nanocellular metal foams. The following sections describe the project goals for these two types of materials as well as the progress made towards these goals in FY04. These sections also provide context for the three publications that have been included in this final report.
Date: January 7, 2005
Creator: Satcher, J. H. Jr.; Hsiung, L. M.; Baumann, T. F.; Maxwell, R. S.; Chinn, S. C.; Hodge, A. M. et al.
Partner: UNT Libraries Government Documents Department
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S829 Airfoil; Period of Performance: 1994--1995

Description: A 16%-thick, natural-laminar-flow airfoil, the S829, for the tip region of 20- to 40-meter-diameter, stall-regulated, horizontal-axis wind turbines has been designed and analyzed theoretically. The two primary objectives of restrained maximum lift, insensitive to roughness, and low profile drag have been achieved. The constraints on the pitching moment and the airfoil thickness have been satisfied. The airfoil should exhibit a docile stall.
Date: January 1, 2005
Creator: Somers, D. M.
Partner: UNT Libraries Government Documents Department
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S827 and S828 Airfoils; Period of Performance: 1994--1995

Description: A family of thick, natural-laminar-flow airfoils, the S827 and S828, for 40- to 50-meter, stall -regulated, horizontal-axis wind turbines has been designed and analyzed theoretically. The two primary objectives of restrained maximum lift, insensitive to roughness, and low profile drag have been achieved. The constraints on the pitching moments and the airfoil thicknesses have been satisfied. The airfoils should exhibit docile stalls.
Date: January 1, 2005
Creator: Somers, D. M.
Partner: UNT Libraries Government Documents Department
open access

AeroDyn Theory Manual

Description: AeroDyn is a set of routines used in conjunction with an aeroelastic simulation code to predict the aerodynamics of horizontal axis wind turbines. These subroutines provide several different models whose theoretical bases are described in this manual. AeroDyn contains two models for calculating the effect of wind turbine wakes: the blade element momentum theory and the generalized dynamic-wake theory. Blade element momentum theory is the classical standard used by many wind turbine designers and generalized dynamic wake theory is a more recent model useful for modeling skewed and unsteady wake dynamics. When using the blade element momentum theory, various corrections are available for the user, such as incorporating the aerodynamic effects of tip losses, hub losses, and skewed wakes. With the generalized dynamic wake, all of these effects are automatically included. Both of these methods are used to calculate the axial induced velocities from the wake in the rotor plane. The user also has the option of calculating the rotational induced velocity. In addition, AeroDyn contains an important model for dynamic stall based on the semi-empirical Beddoes-Leishman model. This model is particularly important for yawed wind turbines. Another aerodynamic model in AeroDyn is a tower shadow model based on potential flow around a cylinder and an expanding wake. Finally, AeroDyn has the ability to read several different formats of wind input, including single-point hub-height wind files or multiple-point turbulent winds.
Date: January 1, 2005
Creator: Moriarty, P. J. & Hansen, A. C.
Partner: UNT Libraries Government Documents Department
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Science & Technology Review March 2005

Description: This issue of Science and Technology Review has the following articles: (1) Enhanced National Security through International Research Collaborations--Commentary by Stephen G. Cochran; (2) Building Networks of Trust through Collaborative Science--Livermore scientists are leading collaborative science and technology projects with colleagues from Central and South Asia and the Middle East; (3) Tracing the Steps in Nuclear Material Trafficking--The Laboratory.s nuclear science expertise is helping to thwart the illicit trafficking of nuclear material; (4) Looking at Earth in Action--Geophysicists at Livermore are using laboratory experiments to examine such issues as how best to store nuclear wastes and how to mitigate the effects of greenhouse gases; and (5) Gamma-Ray Bursts Shower the Universe with Metals--Computer models indicate that gamma-ray bursts from dying stars may be important sources of elements such as iron, zinc, titanium, and copper.
Date: January 25, 2005
Creator: Henson, V E
Partner: UNT Libraries Government Documents Department
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CITRIC ACID AS A SET RETARDER FOR CALCIUM ALUMINATE PHOSPHATE CEMENTS.

Description: Citric acid added as set retarder significantly contributed to enhancing the setting temperature and to extending the thickening time of a calcium aluminate phosphate (CaP) geothermal cement slurry consisting of calcium aluminate cement (CAC) as the base reactant and sodium polyphosphate (NaP) solution as the acid reactant. The set-retarding activity of citric acid was due to the uptake of Ca{sup 2+} ions from the CAC by carboxylic acid groups within the citric acid. This uptake led to the precipitation of a Ca-complexed carboxylate compound as a set-retarding barrier layer on the CAC grains' surfaces. However, this barrier layer was vulnerable to disintegration by the attack of free Ca{sup 2+} ions from CAC, and also to degradation at elevated temperature, thereby promoting the generation of exothermic energy from acid-base reactions between the CAC and NaP after the barrier was broken. The exothermic reaction energy that was promoted in this way minimized the loss in strength of the citric acid-retarded cement. The phase composition assembled in both retarded and non-retarded cements after autoclaving at 180 C encompassed three reaction products, hydroxyapatite (HOAp), hydrogrossular and boehmite, which are responsible for strengthening the autoclaved cement. The first two reaction products were susceptible to reactions with sulfuric acid and sodium sulfate to form crystalline bassanite scale as the corrosion product. The boehmite phase possessed a great resistance to acid and sulfate. Although the bassanite scales clinging to the cement's surfaces were the major factor governing the loss in weight, they served in protecting the cement from further acid- and sulfate-corrosion until their spallation eventually occurred. Nevertheless, the repetitive processes of HOAp and hydrogrossular {yields} bassanite {yields} spallation played an important role in extending the useful lifetime of CaP cement in a low pH environment at 180 C.
Date: January 1, 2005
Creator: SUGAMA,T. & BROTHERS, L. E.
Partner: UNT Libraries Government Documents Department
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Effects of Airfoil Thickness and Maximum Lift Coefficient on Roughness Sensitivity: 1997--1998

Description: A matrix of airfoils has been developed to determine the effects of airfoil thickness and the maximum lift to leading-edge roughness. The matrix consists of three natural-laminar-flow airfoils, the S901, S902, and S903, for wind turbine applications. The airfoils have been designed and analyzed theoretically and verified experimentally in the Pennsylvania State University low-speed, low-turbulence wind tunnel. The effect of roughness on the maximum life increases with increasing airfoil thickness and decreases slightly with increasing maximum lift. Comparisons of the theoretical and experimental results generally show good agreement.
Date: January 1, 2005
Creator: Somers, D. M.
Partner: UNT Libraries Government Documents Department
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Grid-Connected Inverter Anti-Islanding Test Results for General Electric Inverter-Based Interconnection Technology

Description: This report covers testing of General Electric-proposed anti-islanding schemes. The objectives were to: (1) Validate the effectiveness of the proposed anti-islanding schemes; (2) Conduct parametric evaluation of the schemes with respect to control settings and load conditions, including controller gains, load power levels, and load quality factors; and (3) Examine the ability of the distributed resource to ride through a low-voltage condition on the utility grid.
Date: January 1, 2005
Creator: Ye, Z.; Dame, M. & Kroposki, B.
Partner: UNT Libraries Government Documents Department
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Testing of the OBO Bettermann Peak Current Sensor System for Lawrence Livermore National Laboratory

Description: During summer 2004 we studied the reliability of the OBO Bettermann peak current sensor (PCS) monitoring system - (1) credit card-type cards with magnetic strips and (2) a card reader. Three methods were used to generate current for testing the PCS system: (1) a Keytek current generator (2) a capacitor discharge, and (3) rocket triggered lightning. The data obtained from the cards were compared with oscilloscope measurements of the generated currents. Additionally, we tested for nearby natural and nearby rocket triggered lightning by placing cards on an airport runway lighting system lightning-protection counterpoise, on power line grounds, and on the lightning-protection system of an explosive storage igloo at Camp Blanding Army National Guard Base. In all experiments exposed cards were read multiple times to test the consistency of the measurement. Each card read zero before each experiment. The Keytek current generator produced a maximum peak current of 5 kA which was unrecorded by the PCS system despite the OBO Bettermann claim that currents larger than 3 kA could be recorded. Three cards were exposed to triggered lightning current and gave proper results (the PCS card measurement deviated less than +- 2 kA from the peak current value measured by research equipment). Cards exposed to the current of the capacitor discharge, which was initiated by triggering a spark gap, generally yielded current readings about four times higher than the actual value, but proper readings were observed with some card orientations and locations. Two of the 7 cards tested with the Keytek and 4 of the 17 cards placed on the explosive storage igloo and on the runway counterpoise yielded non-zero current on some readings and zero current on other readings, while all other cards in those locations produced zero current for all readings of the card. The cause of the apparently …
Date: January 10, 2005
Creator: Schoene, J; Uman, M A; Aurele, M; Rambo, K J; Jerauld, J E & Schnetzer, G
Partner: UNT Libraries Government Documents Department
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Self-Assembly Ce Oxide/Organopolysiloxane Composite Coatings.

Description: A self-assembly composite synthesis technology was used to put together a Ce(OH){sub 3}-dispersed poly-acetamide-acetoxyl methyl-propylsiloxane (PAAMPA) organometallic polymer. Three spontaneous reactions were involved; condensation, amidation, and acetoxylation, between the Ce acetate and aminopropylsilane triol (APST) at 150 C. An increase in temperature to 200 C led to the in-situ phase transformation of Ce(OH){sub 3} into Ce{sub 2}O{sub 3} in the PAAMPA matrix. A further increase to 250 C caused oxidative degradation of the PAAMPA, thereby generating copious fissures in the composite. We assessed the potential of Ce(OH){sub 3}/ and Ce{sub 2}O{sub 3}/ PAAMPA composite materials as corrosion-preventing coatings for carbon steel and aluminum. The Ce{sub 2}O{sub 3} composite coating displayed better performance in protecting both metals against NaCl-caused corrosion than did the Ce(OH){sub 3} composite. Using this coating formed at 200 C, we demonstrated that the following four factors played an essential role in further mitigating the corrosion of the metals: First was a minimum susceptibility of coating's surface to moisture; second was an enhanced densification of the coating layer; third was the retardation of the cathodic oxygen reduction reaction at the metal's corrosion sites due to the deposition of Ce{sub 2}O{sub 3} as a passive film over the metal's surface; and, fourth was its good adherence to metals. The last two factors contributed to minimizing the cathodic delamination of coating film from the metal's surface. We also noted that the affinity of the composite with the surface of aluminum was much stronger than that with steel. Correspondingly, the rate of corrosion of aluminum was reduced as much as two orders of magnitude by a nanoscale thick coating. In contrast, its ability to reduce the corrosion rate of steel was lower than one order of magnitude.
Date: January 1, 2005
Creator: Sugama, T.; Sabatini, R. & Gawlik, K.
Partner: UNT Libraries Government Documents Department
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Appendix D-12A Building 332C Waste Accumulation Area

Description: This appendix is designed to provide information specific to the Building 332C Waste Accumulation Area (B-332C WAA), a waste storage area. This appendix is not designed to be used as a sole source of information. All general information that is not specific to the B-332C WAA is included in the Contingency Plan for Waste Accumulation Areas, dated July 2004, and should be referenced. The B-332C WAA is located in the southwest quadrant of the LLNL Main Site in Building 332, Room 1330. Hazardous and mixed wastes may be stored at the B-332C WAA for 90 days or less, until transferred to the appropriate Radioactive and Hazardous Waste Management (RHWM) facility or other permitted treatment, storage or disposal facility (TSDF). Radioactive waste may also be stored at the WAA. The design storage capacity of this WAA is 2,200 gallons.
Date: January 21, 2005
Creator: Chase, Dawn
Partner: UNT Libraries Government Documents Department
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Preliminary Authorization Basis Document For the Proposed Biological Safety Level 3 (BSL-3) Facility (B368) at Lawrence Livermore National Laboratory Revision 2

Description: The Lawrence Livermore National Laboratory Integrated Safety Management (ISM) System Description (LLNL 2002) and the Task Plan for the Preparation of Authorization Basis Documentation for the proposed Biosafety Level 3 Laboratory at Lawrence Livermore National Laboratory (DOE 2002a) require a PABD be prepared for the proposed BSL-3 Facility. NNSA-OAK approval is required prior to its construction. This Preliminary Authorization Basis Documentation (PABD) formalizes and documents the hazard evaluation and its results for the Biosafety level 3 (BSL-3) facility. The PABD for the proposed BSL-3 facility provides the following information: (1) BSL-3 facility's site description; (2) general description of the BSL-3 facility and its operations; (3) identification of facility hazards; (4) generic hazard analysis; (5) identification of controls important to safety; and (6) safety management programs. The PABD characterizes the level of intrinsic potential hazard associated with a facility and provides the basis for its hazard classification. The hazard classification determines the level of safety documentation required and the level of review and approval for the safety analysis. The hazards of primary concern associated with the BSL-3 facility are biological. The hazard classification is determined by comparing facility inventories of biological materials and activities with the BSL-3 threshold established by the Centers for Disease Control and Prevention (CDC) and the National Institutes of Health (NIH) for BSL-3 facilities.
Date: January 4, 2005
Creator: Altenbach, T & Nguyen, S
Partner: UNT Libraries Government Documents Department
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Advanced Photon Source Activity Report 2003: Report of Work Conducted at the APS, January 2003-December 2003, Synchrotron x-ray diffraction at the APS, Sector 16 (HPCAT)

Description: We present here the summary of the results of our studies using the APS synchrotron beamline IDB Sector 16 (HPCAT). Optical calibration of pressure sensors for high pressures and temperatures: The high-pressure ruby scale for static measurements is well established to at least 100 GPa (about 5% accuracy), however common use of this and other pressure scales at high temperature is clearly based upon unconfirmed assumptions. Namely that high temperature does not affect observed room temperature pressure derivatives. The establishment of a rigorous pressure scale along with the identification of appropriate pressure gauges (i.e. stable in the high P-T environment and easy to use) is important for securing the absolute accuracy of fundamental experimental science where results guide the development of our understanding of planetary sciences, geophysics, chemistry at extreme conditions, etc. X-ray diffraction in formic acid under high pressure: Formic acid (HCOOH) is common in the solar system; it is a potential component of the Galilean satellites. Despite this, formic acid has not been well-studied at high temperatures and pressures. A phase diagram of formic acid at planetary interior pressures and temperatures will add to the understanding of planetary formation and the potential for life on Europa. Formic acid (unlike most simple organic acids) forms low-temperature crystal structures characterized by infinite hydrogen-bonded chains of molecules. The behavior of these hydrogen bonds at high pressure is of great interest. Our current research fills this need.
Date: January 27, 2005
Creator: Goncharov, A F; Zaug, J M & Crowhurst, J C
Partner: UNT Libraries Government Documents Department
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Metal-Containing Organic and Carbon Aerogels for Hydrogen Storage

Description: This document and the accompanying manuscript summarize the technical accomplishments of our one-year LDRD-ER effort. Hydrogen storage and hydrogen fuel cells are important components of the 2003 Hydrogen Fuel Initiative focused on the reduction of America's dependence on oil. To compete with oil as an energy source, however, one must be able to transport and utilize hydrogen at or above the target set by DOE (6 wt.% H{sub 2}) for the transportation sector. Other than liquid hydrogen, current technology falls well short of this DOE target. As a result, a variety of materials have recently been investigated to address this issue. Carbon nanostructures have received significant attention as hydrogen storage materials due to their low molecular weight, tunable microporosity and high specific surface areas. For example, the National Renewable Energy Laboratory (NREL) achieved 5 to 10 wt.% H{sub 2} storage using metal-doped carbon nanotubes. That study showed that the intimate mix of metal nanoparticles with graphitic carbon resulted in the unanticipated hydrogen adsorption at near ambient conditions. The focus of our LDRD effort was the investigation of metal-doped carbon aerogels (MDCAs) as hydrogen storage materials. In addition to their low mass densities, continuous porosities and high surface areas, these materials are promising candidates for hydrogen storage because MDCAs contain a nanometric mix of metal nanoparticles and graphitic nanostructures. For FY04, our goals were to: (1) prepare a variety of metal-doped CAs (where the metal is cobalt, nickel or iron) at different densities and carbonization temperatures, (2) characterize the microstructure of these materials and (3) initiate hydrogen adsorption/desorption studies to determine H2 storage properties of these materials. Since the start of this effort, we have successfully prepared and characterized Ni- and Co-doped carbon aerogels at different densities and carbonization temperatures. The bulk of this work is described in the attached manuscript …
Date: January 10, 2005
Creator: Satcher, J. H. Jr.; Baumann, T. F. & Herberg, J. L.
Partner: UNT Libraries Government Documents Department
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S904 and S905 Airfoils: May 1998--January 1999

Description: A family of natural-laminar-flow airfoils, the S904 and S905, for cooling-tower fans has been designed and analyzed theoretically. The two primary objectives of high maximum lift, relatively insensitive to roughness, and low profile drag have been achieved. The constraint on the lift a zero angle of attack has not been satisfied. The constraints on the pitching moment and the airfoil thicknesses have essentially been satisfied. The airfoils should exhibit docile stalls.
Date: January 1, 2005
Creator: Somers, D. M.
Partner: UNT Libraries Government Documents Department
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Attempts to Produce D2-Gas-Filled Be Shells

Description: We have attempted to fabricate some 0.5 mm diameter D{sub 2}-gas-filled Be shells by coating gas-filled PVA-coated GDP mandrels with Cu-doped Be. We find that during the coating all (or most) of the gas leaks out. This is likely due to either small cracks or holes in the coating that are formed at the earliest points and are maintained during the thickness build-up of the coating, and/or to some level of intrinsic porosity in the coating. This memo documents our efforts.
Date: January 14, 2005
Creator: Cook, B; McElfresh, M; Alford, C; Fought, E & Letts, S
Partner: UNT Libraries Government Documents Department
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R&D Advancement, Technology Diffusion, and Impact on Evaluation of Public R&D

Description: In a 2001 report titled ''Research at DOE: Was It Worth It?'', a National Research Council (NRC) committee defined a set of simplifying rules to estimate the net economic benefits from technologies supported by the Department of Energy (DOE). This NREL paper evaluates the efficacy of the NRC rules compared to published literature on acceleration of technology introduction into markets, technology diffusion, and infrastructure change. It also offers considerations for revisions of the rules that call for the use of technology and sector-specific data, advanced forecasting techniques, and sensitivity analysis to test the robustness of the methodology.
Date: January 1, 2005
Creator: Moore, M. C.; Arent, D. J. & Norland, D.
Partner: UNT Libraries Government Documents Department
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Results of LLNL's Participation in the 16th OPCW Proficiency Test

Description: The Sixteenth Official OPCW Proficiency Test started in October 2004. The samples were prepared by scientists affiliated with the Forensic Science Center at the Lawrence Livermore National Laboratory in Livermore, California, USA. The work was funded by the US Department of Energy. The test scenario and the spiking and background chemicals were discussed and agreed in advance with the OPCW. The samples were prepared in accordance with ''Work Instruction for the Preparation of Test Samples for OPCW Proficiency Tests'' (Document No.: QDOC/LAB/WI/PT2). The preparation of the test samples and their analysis are described in this report.
Date: January 24, 2005
Creator: Gregg, H. R. & Alcaraz, A.
Partner: UNT Libraries Government Documents Department
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FY04 Engineering Technology Reports Laboratory Directed Research and Development

Description: This report summarizes the science and technology research and development efforts in Lawrence Livermore National Laboratory's Engineering Directorate for FY2004, and exemplifies Engineering's more than 50-year history of developing the technologies needed to support the Laboratory's missions. Engineering has been a partner in every major program and project at the Laboratory throughout its existence and has prepared for this role with a skilled workforce and the technical resources developed through venues like the Laboratory Directed Research and Development Program (LDRD). This accomplishment is well summarized by Engineering's mission: ''Enable program success today and ensure the Laboratory's vitality tomorrow''. Engineering's investment in technologies is carried out through two programs, the ''Tech Base'' program and the LDRD program. LDRD is the vehicle for creating those technologies and competencies that are cutting edge. These require a significant level of research or contain some unknown that needs to be fully understood. Tech Base is used to apply technologies to a Laboratory need. The term commonly used for Tech Base projects is ''reduction to practice''. Therefore, the LDRD report covered here has a strong research emphasis. Areas that are presented all fall into those needed to accomplish our mission. For FY2004, Engineering's LDRD projects were focused on mesoscale target fabrication and characterization, development of engineering computational capability, material studies and modeling, remote sensing and communications, and microtechnology and nanotechnology for national security applications. Engineering's five Centers, in partnership with the Division Leaders and Department Heads, are responsible for guiding the long-term science and technology investments for the Directorate. The Centers represent technologies that have been identified as critical for the present and future work of the Laboratory, and are chartered to develop their respective areas. Their LDRD projects are the key resources to attain this competency, and, as such, nearly all of Engineering's portfolio falls …
Date: January 27, 2005
Creator: Sharpe, R M
Partner: UNT Libraries Government Documents Department
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