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Description: GEORGE is an automatic high-speed electronic digital computer designed and constructed by ANL. Operating features of GEORGE are described, and a practical set of instructions is given that will enable a prospective user to construct codes, operate the machine and its auxiliary equipment, use the basic routines available in the routine library, and decide whether a particular problem is suitable on the basis of capacity, speeds and auxiliary equipment. (W.D.M.)
Date: May 1, 1959
Creator: Kassel, L.
Partner: UNT Libraries Government Documents Department


Description: Protruding rocket antennas of low silhouette are examined using transmission-line concepts. The theory was developed specifically for nondissipative terminations and line sections; however, the formulas are readily generalized to include ohmic losses in the lines and terminations. Adaptive computations may be made for conductors other than circular and the theory may be used to analyze antennas of other missiles. (J.R.D.)
Date: November 20, 1958
Creator: King, R.W.P.; Harrison, C.W. Jr. & Denton, D.H. Jr.
Partner: UNT Libraries Government Documents Department

Direct-Write Precision Resistors for Ceramic Packages

Description: A direct-write approach to f abricate high precision resistors is reported. Special attention is paid to the effect of print thickrw;s on the resistance value of buried resistors after a low temperature co-firing process. The results show that the direct-write approach provides a superior line definition and thickness control over a traditional screen printing process. Microstructural analysis indicates that there is an interdiffused layer developed between the resistor material and the low temperature co-fired ceramic substrate. These observations are consistent with electrical IIH.SUKHIlentS which show that resistance increases as the effective cross-sectional area is reduced. Th: resistance data show that the standard deviations for resistors printed on a 6" x 6" area are 59Z0 and 15$Z0 for the direct-write and the screen-printed patterns, respectively.
Date: November 30, 1998
Creator: Dai, S.; Dimos, D.; Huang, R.F.; Rodriguez, M.A.; Wilcox, D. & Yang, P.
Partner: UNT Libraries Government Documents Department

A Brief Discussion of Radiation Hardening of CMOS Microelectronics

Description: Commercial microchips work well in their intended environments. However, generic microchips will not fimction correctly if exposed to sufficient amounts of ionizing radiation, the kind that satellites encounter in outer space. Modern CMOS circuits must overcome three specific concerns from ionizing radiation: total-dose, single-event, and dose-rate effects. Minority-carrier devices such as bipolar transistors, optical receivers, and solar cells must also deal with recombination-generation centers caused by displacement damage, which are not major concerns for majority-carrier CMOS devices. There are ways to make the chips themselves more resistant to radiation. This extra protection, called radiation hardening, has been called both a science and an art. Radiation hardening requires both changing the designs of the chips and altering the ways that the chips are manufactured.
Date: December 18, 1998
Creator: Myers, D.R.
Partner: UNT Libraries Government Documents Department

Detection and Measurement of Nuclear Radiation

Description: The technique of radiation characterization is reviewed, with particular emphasis on new methods and their practi-cal aspects. Each type of detector is discussed in terms of its principle of operation and its applicability to various problems in counting and spectrometry. Auxiliary electronic instrumentation and the function of each instrument are described in general terms. Other topics discussed include low-level counting, absolute counting, and the mounting of radioactive sources. (137 references.) (C.H.)
Date: December 1, 1961
Creator: O'Kelley, G. D.
Partner: UNT Libraries Government Documents Department

Automotive Vehicle Sensors

Description: This report is an introduction to the field of automotive vehicle sensors. It contains a prototype data base for companies working in automotive vehicle sensors, as well as a prototype data base for automotive vehicle sensors. A market analysis is also included.
Date: September 1995
Creator: Sheen, S. H.; Raptis, A. C. & Moscynski, M. J.
Partner: UNT Libraries Government Documents Department

MEMS inertial sensors with integral rotation means.

Description: The state-of-the-art of inertial micro-sensors (gyroscopes and accelerometers) has advanced to the point where they are displacing the more traditional sensors in many size, power, and/or cost-sensitive applications. A factor limiting the range of application of inertial micro-sensors has been their relatively poor bias stability. The incorporation of an integral sensitive axis rotation capability would enable bias mitigation through proven techniques such as indexing, and foster the use of inertial micro-sensors in more accuracy-sensitive applications. Fabricating the integral rotation mechanism in MEMS technology would minimize the penalties associated with incorporation of this capability, and preserve the inherent advantages of inertial micro-sensors.
Date: September 1, 2003
Creator: Kohler, Stewart M.
Partner: UNT Libraries Government Documents Department

Microfabrication with femtosecond laser processing : (A) laser ablation of ferrous alloys, (B) direct-write embedded optical waveguides and integrated optics in bulk glasses.

Description: At Sandia National Laboratories, miniaturization dominates future hardware designs, and technologies that address the manufacture of micro-scale to nano-scale features are in demand. Currently, Sandia is developing technologies such as photolithography/etching (e.g. silicon MEMS), LIGA, micro-electro-discharge machining (micro-EDM), and focused ion beam (FIB) machining to fulfill some of the component design requirements. Some processes are more encompassing than others, but each process has its niche, where all performance characteristics cannot be met by one technology. For example, micro-EDM creates highly accurate micro-scale features but the choice of materials is limited to conductive materials. With silicon-based MEMS technology, highly accurate nano-scale integrated devices are fabricated but the mechanical performance may not meet the requirements. Femtosecond laser processing has the potential to fulfill a broad range of design demands, both in terms of feature resolution and material choices, thereby improving fabrication of micro-components. One of the unique features of femtosecond lasers is the ability to ablate nearly all materials with little heat transfer, and therefore melting or damage, to the surrounding material, resulting in highly accurate micro-scale features. Another unique aspect to femtosecond radiation is the ability to create localized structural changes thought nonlinear absorption processes. By scanning the focal point within transparent material, we can create three-dimensional waveguides for biological sensors and optical components. In this report, we utilized the special characteristics of femtosecond laser processing for microfabrication. Special emphasis was placed on the laser-material interactions to gain a science-based understanding of the process and to determine the process parameter space for laser processing of metals and glasses. Two areas were investigated, including laser ablation of ferrous alloys and direct-write optical waveguides and integrated optics in bulk glass. The effects of laser and environmental parameters on such aspects as removal rate, feature size, feature definition, and ablation angle during the ablation ...
Date: November 1, 2004
Creator: Guo, Junpeng; McDaniel, Karen Lynn; Palmer, Jeremy Andrew; Yang, Pin; Griffith, Michelle Lynn; Vawter, Gregory Allen et al.
Partner: UNT Libraries Government Documents Department

Hyper-spectral scanner design and analysis

Description: This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). An earlier project produced rough designs for key components of a compact hyper-spectral sensor for environmental and ecological measurements. Such sensors could be deployed on unmanned vehicles, aircraft, or satellites for measurements important to agriculture, the environment, and ecologies. This represents an important advance in remote sensing. Motorola invited us to propose an add-on, proof-of-principle sensor for their Comet satellite, whose primary mission is to demonstrate a channel of the IRIDIUM satellite communications system. Our project converted the preliminary designs from the previous effort into final designs for the telescope, camera, computer and interfaces that constitute the hyper-spectral scanning sensor. The work concentrated on design, fabrication, preliminary integration, and testing of the electronic circuit boards for the computer, data compression board, and interface board for the camera-computer and computer-modulator (transmitter) interfaces.
Date: June 1, 1996
Creator: Canavan, G.; Moses, J. & Smith, R.
Partner: UNT Libraries Government Documents Department

Monitoring energy use of copiers to determine program design and potential savings for the Energy Star Copier program

Description: In the past five years, considerable attention has been focused on the electricity use of office equipment in commercial office buildings. Several groups have monitored energy use of PCs, monitors, printers and fax machines. However, little attention has been paid to monitoring energy use of copiers. Procedures for testing energy usage and usage profiles of copiers are needed to make valid comparisons between machines and to determine overall energy use and potential energy savings. In this paper, the authors present a method to analyze the energy use and usage profiles of copiers. This method is determined through long-term measurements from a Watt-hour meter connected to the copier and by measuring light flashes from the copier. Energy use from the copier can also be estimated by using a test procedure developed by Dandridge. Results from using the long term monitoring methods will be presented for several different sized copiers, and compared to the estimated energy use derived from the American Society for Testing and Materials (ASTM) method. After summarizing these results, the authors determine criteria for a program to recognize energy-efficient copiers. These criteria were submitted as an Energy Star Copier program to the Environmental Protection Agency (EPA). The new Energy Star Copier Program was announced in July 1995, with criteria based on these suggestions. Using the final Energy Star Copier program criteria and this data, the authors determine potential future savings for the program. The ability to automatically turn the copier off at night is the greatest energy-saving feature most copiers can have. The best way to reduce overall office costs is to have the copier set automatically to make double-sided copies.
Date: August 1, 1996
Creator: Dandridge, C.B.; Norford, L.K. & Nordman, B.
Partner: UNT Libraries Government Documents Department

Power electronics and electric machinery challenges and opportunities in electric and hybrid vehicles

Description: The development of power electronics and electric machinery presents significant challenges to the advancement of electric and hybrid vehicles. Electronic components and systems development for vehicle applications have progressed from the replacement of mechanical systems to the availability of features that can only be realized through interacting electronic controls and devices. Near-term applications of power electronics in vehicles will enable integrated powertrain controls, integrated chassis system controls, and navigation and communications systems. Future applications of optimized electric machinery will enable highly efficient and lightweight systems. This paper will explore the areas where research and development is required to ensure the continued development of power electronics and electric machines to meet the rigorous demands of automotive applications. Additionally, recent advances in automotive related power electronics and electric machinery at Oak Ridge National Laboratory will be explained. 3 refs., 5 figs.
Date: June 1, 1997
Creator: Adams, D.J.; Hsu, J.S.; Young, R.W. & Peng, F.Z.
Partner: UNT Libraries Government Documents Department

Predicting Electronic Failure from Smoke

Description: Smoke can cause electronic equipment to fail through increased leakage currents and shorts. Sandia National Laboratories is studying the increased leakage currents caused by smoke with varying characteristics. The objective is to develop models to predict the failure of electronic equipment exposed to smoke. This requires the collection of data on the conductivity of smoke and knowledge of critical electrical systems that control high-consequence operations. We have found that conductivity is a function of the type of fuel, how it is burned, and smoke density. Video recordings of highly biased dc circuits exposed in a test chamber show that during a fire, smoke is attracted to high voltages and can build fragile carbon bridges that conduct leakage currents. The movement of air breaks the bridges, so the conductivity decreases after the fire is extinguished and the test chamber is vented. During the fire, however, electronic equipment may not operate correctly, leading to problems for critical operations dependent on electronic control. The potential for electronic failure is highly dependent on the type of electrical circuit, and Sandia National Laboratories plans to include electrical circuit modeling in the failure models.
Date: January 15, 1999
Creator: Tanaka, T.J.
Partner: UNT Libraries Government Documents Department

Fabrication, measurement, and alignment uniformity analysis of linear arrays of optical fibers

Description: Techniques were developed for assembling a linear array of optical fibers between two silicon plates and polishing the fiber ends in a plane perpendicular to the fiber axis. The silicon plates contained etched V-grooves for capturing the fibers. Optical fibers from two sources were evaluated, along with silicon plates supplied by two sources. Most of the arrays were assembled by epoxy bonding, but some effort was made to form a eutectic bond using gold metallized fibers with gold-coated silicon plates. Measurements were made of the uniformity of spacing of the fiber mode field centers in the linear array. The work was performed to develop a multi-fiber linear array connector to couple optical signals to and from optoelectronic devices.
Date: June 1, 1997
Creator: Klingsporn, P.E.
Partner: UNT Libraries Government Documents Department

NASA Boeing 757 HIRF test series low power on-the-ground tests

Description: The data acquisition phase of a program intended to provide data for the validation of computational, analytical, and experimental techniques for the assessment of electromagnetic effects in commercial transports; for the checkout of instrumentation for following test programs; and for the support of protection engineering of airborne systems has been completed. Funded by the NASA Fly-By-Light/ Power-By-Wire Program, the initial phase involved on-the-ground electromagnetic measurements using the NASA Boeing 757 and was executed in the LESLI Facility at the USAF Phillips Laboratory. The major participants in this project were LLNL, NASA Langley Research Center, Phillips Laboratory, and UIE, Inc. The tests were performed over a five week period during September through November, 1994. Measurements were made of the fields coupled into the aircraft interior and signals induced in select structures and equipment under controlled illumination by RF fields. A characterization of the ground was also performed to permit ground effects to be included in forthcoming validation exercises. This report and the associated test plan that is included as an appendix represent a definition of the overall on-the-ground test program. They include descriptions of the test rationale, test layout, and samples of the data. In this report, a detailed description of each executed test is provided, as is the data identification (data id) relating the specific test with its relevant data files. Samples of some inferences from the data that will be useful in protection engineering and EM effects mitigation are also presented. The test plan which guided the execution of the tests, a test report by UIE Inc., and the report describing the concrete pad characterization are included as appendices.
Date: August 1, 1996
Creator: Poggio, A.J.; Pennock, S.T.; Zacharias, R.A.; Avalle, C.A. & Carney, H.L.
Partner: UNT Libraries Government Documents Department