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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

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

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

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


Description: Hanford Atomic Production Operation specification guides for instruments, radiation detection instruments, instrumentation, thermocouples, orifices, process control instruments, and electronic design are presented. Details of this manual are given in TID-4100(Suppl.). (N.W.R.)
Date: January 1, 1963
Partner: UNT Libraries Government Documents Department

Spray Cooling with HFC-134a and HFO-1234yf for Thermal Management of Automotive Power Electronics

Description: This study aims to experimentally investigate the spray cooling characteristics for active two-phase cooling of automotive power electronics. Tests are conducted on a small-scale, closed loop spray cooling system featuring a pressure atomized spray nozzle. Two types of refrigerants, HFC-134a (R-134a) and HFO-1234yf, are selected as the working fluids. The test section (heater), made out of oxygen-free copper, has a 1-cm2 plain, smooth surface prepared following a consistent procedure, and would serve as a baseline case. Matching size thick film resistors, attached onto the copper heaters, generate heat and simulate high heat flux power electronics devices. The tests are conducted by controlling the heat flux in increasing steps, and recording the corresponding steady-state temperatures to obtain cooling curves. The working fluid is kept at room temperature level (22oC). Performance comparisons are made based on heat transfer coefficient (HTC) and critical heat flux (CHF) values. Effects of spray characteristics and liquid flow rates on the cooling performance are investigated with the selected coolants. Three types of commercially available nozzles that generate full-cone sprays with fine droplets are utilized in the tests. Effect of liquid flow rate is evaluated varying flow rates at 2, 3, 4 ml/s. The experimental results obtained from this study provide a framework for spray cooling performance with the current and next-generation refrigerants aimed for advanced thermal management of automotive power electronics.
Date: December 2015
Creator: Yaddanapudi, Satvik Janardhan
Partner: UNT Libraries

Second Line of Defense Help Desk: Electronic Maintenance Reports - Local Maintenance Provider User Guide Rev. 1

Description: The Electronic Maintenance Report forms present a uniform dataset for analysis of Sustainability metrics. These forms collect readily minable data while allowing the attachment of site-specific checklists or other supporting files for review by the Sustainability Manager and Program Management.
Date: December 14, 2011
Creator: Leigh, Richard J.
Partner: UNT Libraries Government Documents Department


Description: High resolution mass spectrometers are specialized systems that allow researchers to determine the exact mass of samples to four significant digits by using magnetic and electronic sector mass analyzers. Many of the systems in use today at research laboratories and universities were designed and built more than two decades ago. The manufacturers of these systems have abandoned the support for some of the mass spectrometers and parts to power and control them have become scarce or obsolete. The Savannah River National Laboratory has been involved in the upgrade of the electronics and software for these legacy machines. The Electronics Upgrade of High Resolution Mass Spectrometers consists of assembling high-end commercial instrumentation from reputable manufacturers with a minimal amount of customization to replace the electronics for the older systems. By taking advantage of advances in instrumentation, precise magnet control can be achieved using high resolution current sources and continuous feedback from a high resolution hall-effect probe. The custom equipment include a precision voltage divider/summing amplifier chassis, high voltage power supply chassis and a chassis for controlling the voltage emission for the mass spectrometer source tube. The upgrade package is versatile enough to interface with valve control, vacuum and other instrumentation. Instrument communication is via a combination of Ethernet and traditional IEEE-488 GPIB protocols. The system software upgrades include precision control, feedback and spectral waveform analysis tools.
Date: March 10, 2008
Creator: Mcintosh, J & Joe Cordaro, J
Partner: UNT Libraries Government Documents Department


Description: Thesis submitted to University of Tennessee, Knoxville. A double time- of-flight apparatus constructed for measurements on fission fragments is described, and the theory and procedures for the measurements are outlined. The accuracy of the technique, limitations of the apparatus, and physical factors affecting the measurements are analyzed. 44 references. (D.C.W.)
Date: September 13, 1963
Creator: Mruk, W.F.
Partner: UNT Libraries Government Documents Department


Description: Progress is reported on instrumentation and controls. Topics covered include: electronic systems and components, semiconductor research, radiation monitoring systems, radiation-detectlon instruments and components, data handling and computation, process instrumentation and control systems, process instrumentation development, reactor instrumentation and controls, and support for highvoltage accelerator program. Separate abstracts were prepared for each topic. (M.C.G.)
Date: February 1, 1963
Partner: UNT Libraries Government Documents Department