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A Statistical Characterization of Electroexplosive Devices Relevant to Electromagnetic Compatibility Assessment

Description: Abstract: Electroexplosive devices (EEDs) are electrically fired explosive initiators used in a wide variety of applications. The nature of most of these applications requires that the devices function with near certainty when required and remain inactive otherwise. Recent concern with pulsed electromagnetic interference (EMI) and nuclear electromagnetic pulse (EMP) made apparent the lack of methodology for assessing EED vulnerability. A new and rigorous approach for characterizing EED firing levels is developed in the context of statistical linear models and is demonstrated in this paper. We combine statistical theory and methodology with thermodynamic modeling to determine the probability that an EED, of a particular type, fires when excited by a pulse of a given width and amplitude. The results can be applied to any type of EED for which the hot-wire explosive binder does not melt below the firing temperature. Included are methods.for assessing model validity and for obtaining probability plots, called "Firing Likelihood Plots". A method of measuring the thermal time constant of an EED is given. This parameter is necessary to evaluate the effect of a train of pulses. These statistical methods are both more general and more efficient than previous methods for EED assessment. The results provide information which is crucial for evaluating the effects of currents induced by impulsive electromagnetic fields of short duration relative to the EEDs thermal time constant.
Date: May 1986
Creator: Friday, Dennis S. & Adams, John W.
Partner: UNT Libraries Government Documents Department

Electromagnetic Compatibility and Interference Metrology

Description: From abstract: The material included in this report is intended for a short course on electromagnetic compatibility/interference (EMC/EMI) metrology to be offered jointly by the staff of the Fields Characterization Group (723.03) and the Interference Characterization Group (723.04) of the Electromagnetic Fields Division (723). The purpose of this short course is to present a review of some of the radiated EMC/EMI measurement methods, to which the National Bureau of Standards (NBS) at Boulder, Colorado, has made significant contributions during the past two decades.
Date: July 1986
Creator: Ma, Mark T. & Kanda, M.
Partner: UNT Libraries Government Documents Department

60-day waste compatibility safety issues and final results for TX-244 grab samples

Description: Three grab samples (244-TX-96-1, 244-TX-96-2, and 244-TX-96-3) were taken from Riser 8 of Tank 241-TX-244 on October 18, 1996, and received by 222-S Laboratory on October 18, 1996. These samples were analyzed in accordance with Compatibility Grab Sampling and Analysis Plan (TSAP) and Data Quality Objectives for Tank Farms Waste Compatibility Program (DQO) in support ofthe Waste Compatibility Program. Notifications were made in accordance with TSAP for pH and OH- analyses. Upon further review, the pH notification was deemed unnecessary, as the notification limit did not apply to this tank.
Date: February 5, 1997
Creator: Nuzum, J. L.
Partner: UNT Libraries Government Documents Department

Rapid thermal outgassing of component samples

Description: This paper/presentation describes the rapid thermal outgassing tests that were ran to provide an inventory of all gasses present in the weld channel during the weld. The component samples tested were of all materials that are exposed to the channel during the temperature excursion due to the welding operation. The temperature ramps were determined from previous weld tests. The test equipment, test procedures, and the data collection system is described. They present the data and their interpretation of it.
Date: March 26, 1999
Creator: Beat, T G & Moffitt, K
Partner: UNT Libraries Government Documents Department

Cladding Alloys for Fluoride Salt Compatibility

Description: This report provides an overview of several candidate technologies for cladding nickel-based corrosion protection layers onto high-temperature structural alloys. The report also provides a brief overview of the welding and weld performance issues associated with joining nickel-clad nickel-based alloys. From the available techniques, two cladding technologies were selected for initial evaluation. The first technique is a line-of-sight method that would be useful for cladding large structures such as vessel interiors or large piping. The line-of-sight method is a laser-based surface cladding technique in which a high-purity nickel powder mixed into a polymer binder is first sprayed onto the surface, baked, and then rapidly melted using a high-power laser. The second technique is a vapor phase technique based on the nickel-carbonyl process that is suitable for cladding inaccessible surfaces such as the interior surfaces of heat exchangers. An initial evaluation for performed on the quality of nickel claddings processed using the two selected cladding techniques.
Date: June 1, 2011
Creator: Muralidharan, Govindarajan; Wilson, Dane F; Walker, Larry R; Santella, Michael L & Holcomb, David Eugene
Partner: UNT Libraries Government Documents Department

Design of Racetrack Coils for High Field Dipole Magnets

Description: The magnet group at LBNL is currently in the process of developing high-field accelerator magnets for use in future colliders. One of the primary challenges is to provide a design which is cost-effective and simple to manufacture, at the same time resulting in good training performance and field quality adequate for accelerator operation. Recent studies have focused on a racetrack geometry that has the virtues of simplicity and conductor compatibility. The results have been applied to the design of a series of prototype high-field magnets based on Nb{sub 3}Sn conductor.
Date: September 8, 2000
Creator: Sabbi, G.; Caspi, S.; Gourlay, S.A.; Hafalia, R.; Jackson, A.; Lietzke, A. et al.
Partner: UNT Libraries Government Documents Department

Ductility Characterization of U-6Nb and Ta-W Alloys

Description: We have previously evaluated the ductility behaviors of U-6Nb and pure Ta. One important observation was that both alloys have very stable necking ductility independent of test conditions. In contrast, uniform ductility varied significantly depending upon strain rates and temperatures. In general, higher strain rate and lower temperature reduce the uniform ductility. Using literature data, we have developed two dynamic ductility models to predict the ductility behaviors of pure-Ta and water-quenched U-6Nb respectively under extreme conditions. In this study we further evaluate the aging effect on U-6Nb and the W-addition effect on Ta. For U-6Nb, the objective is to determine whether or not the ductility degradation by low-temperature aging mostly measured in quasi-static condition can still be observed under dynamic loading (high strain rate) condition. For Ta-W alloys, the focus is to identify the key control parameter so that the optimal condition of high-strength/high-ductility of Ta-10W can be achieved for certain defense-related applications.
Date: September 15, 2006
Creator: Sun, T & Cervantes, O
Partner: UNT Libraries Government Documents Department

LIP: The Livermore Interpolation Package, Version 1.4

Description: This report describes LIP, the Livermore Interpolation Package. Because LIP is a stand-alone version of the interpolation package in the Livermore Equation of State (LEOS) access library, the initials LIP alternatively stand for the 'LEOS Interpolation Package'. LIP was totally rewritten from the package described in [1]. In particular, the independent variables are now referred to as x and y, since the package need not be restricted to equation of state data, which uses variables {rho} (density) and T (temperature). LIP is primarily concerned with the interpolation of two-dimensional data on a rectangular mesh. The interpolation methods provided include piecewise bilinear, reduced (12-term) bicubic, and bicubic Hermite (biherm). There is a monotonicity-preserving variant of the latter, known as bimond. For historical reasons, there is also a biquadratic interpolator, but this option is not recommended for general use. A birational method was added at version 1.3. In addition to direct interpolation of two-dimensional data, LIP includes a facility for inverse interpolation (at present, only in the second independent variable). For completeness, however, the package also supports a compatible one-dimensional interpolation capability. Parametric interpolation of points on a two-dimensional curve can be accomplished by treating the components as a pair of one-dimensional functions with a common independent variable. LIP has an object-oriented design, but it is implemented in ANSI Standard C for efficiency and compatibility with existing applications. First, a 'LIP interpolation object' is created and initialized with the data to be interpolated. Then the interpolation coefficients for the selected method are computed and added to the object. Since version 1.1, LIP has options to instead estimate derivative values or merely store data in the object. (These are referred to as 'partial setup' options.) It is then possible to pass the object to functions that interpolate or invert the interpolant at an ...
Date: July 6, 2011
Creator: Fritsch, F N
Partner: UNT Libraries Government Documents Department

LIP: The Livermore Interpolation Package, Version 1.3

Description: This report describes LIP, the Livermore Interpolation Package. Because LIP is a stand-alone version of the interpolation package in the Livermore Equation of State (LEOS) access library, the initials LIP alternatively stand for the ''LEOS Interpolation Package''. LIP was totally rewritten from the package described in [1]. In particular, the independent variables are now referred to as x and y, since the package need not be restricted to equation of state data, which uses variables {rho} (density) and T (temperature). LIP is primarily concerned with the interpolation of two-dimensional data on a rectangular mesh. The interpolation methods provided include piecewise bilinear, reduced (12-term) bicubic, and bicubic Hermite (biherm). There is a monotonicity-preserving variant of the latter, known as bimond. For historical reasons, there is also a biquadratic interpolator, but this option is not recommended for general use. A birational method was added at version 1.3. In addition to direct interpolation of two-dimensional data, LIP includes a facility for inverse interpolation (at present, only in the second independent variable). For completeness, however, the package also supports a compatible one-dimensional interpolation capability. Parametric interpolation of points on a two-dimensional curve can be accomplished by treating the components as a pair of one-dimensional functions with a common independent variable. LIP has an object-oriented design, but it is implemented in ANSI Standard C for efficiency and compatibility with existing applications. First, a ''LIP interpolation object'' is created and initialized with the data to be interpolated. Then the interpolation coefficients for the selected method are computed and added to the object. Since version 1.1, LIP has options to instead estimate derivative values or merely store data in the object. (These are referred to as ''partial setup'' options.) It is then possible to pass the object to functions that interpolate or invert the interpolant at an ...
Date: January 4, 2011
Creator: Fritsch, F N
Partner: UNT Libraries Government Documents Department

Early lessons from deployment of IFC compatible software

Description: The Industry Foundation Classes (IFC) model of the International Alliance for Interoperability (IAI)-an object data model of buildings-is in its seventh year of development. The last three releases of the model (IFC 1.5.1, 2.0 and 2x) have been implemented by a number of ''mission critical'' industry applications. The deployment of such software in real life projects is just starting. The author is exploring lessons from early deployment that are related to end user and general industry readiness for software interoperability, project model population with data and issues with compatibility of project data, built-in limitations in applications and in the data model, exchange file size and the selection of interoperable software for a project, as well as benefits attainable today from the use of interoperable software. He concludes that software interoperability is beginning to work in this industry, although not as smoothly as first expected.
Date: May 1, 2002
Creator: Bazjanac, V.
Partner: UNT Libraries Government Documents Department

Qualitative Reasoning for Additional Die Casting Applications

Description: If manufacturing incompatibility of a product can be evaluated at the early product design stage, the designers can modify their design to reduce the effect of potential manufacturing problems. This will result in fewer manufacturing problems, less redsign, less expensive tooling, lower cost, better quality, and shorter development time. For a given design, geometric reasoning can predict qualitatively the behaviors of a physical manufacturing process by representing and reasoning with incomplete knowledge of the physical phenomena. It integrates a design with manufacturing processes to help designers simultaneously consider design goals and manufacturing constraints during the early design stage. The geometric reasoning approach can encourage design engineers to qualitatively evaluate the compatibility of their design with manufacturing limitations and requirements.
Date: May 28, 2003
Creator: Miller, R. Allen; Cui, Dehua & Ma, Yuming
Partner: UNT Libraries Government Documents Department

Challenges in the Packaging of MEMS

Description: The packaging of Micro-Electro-Mechanical Systems (MEMS) is a field of great importance to anyone using or manufacturing sensors, consumer products, or military applications. Currently much work has been done in the design and fabrication of MEMS devices but insufficient research and few publications have been completed on the packaging of these devices. This is despite the fact that packaging is a very large percentage of the total cost of MEMS devices. The main difference between IC packaging and MEMS packaging is that MEMS packaging is almost always application specific and greatly affected by its environment and packaging techniques such as die handling, die attach processes, and lid sealing. Many of these aspects are directly related to the materials used in the packaging processes. MEMS devices that are functional in wafer form can be rendered inoperable after packaging. MEMS dies must be handled only from the chip sides so features on the top surface are not damaged. This eliminates most current die pick-and-place fixtures. Die attach materials are key to MEMS packaging. Using hard die attach solders can create high stresses in the MEMS devices, which can affect their operation greatly. Low-stress epoxies can be high-outgassing, which can also affect device performance. Also, a low modulus die attach can allow the die to move during ultrasonic wirebonding resulting to low wirebond strength. Another source of residual stress is the lid sealing process. Most MEMS based sensors and devices require a hermetically sealed package. This can be done by parallel seam welding the package lid, but at the cost of further induced stress on the die. Another issue of MEMS packaging is the media compatibility of the packaged device. MEMS unlike ICS often interface with their environment, which could be high pressure or corrosive. The main conclusion we can draw about MEMS ...
Date: March 26, 1999
Creator: Malshe, A.P.; Singh, S.B.; Eaton, W.P.; O'Neal, C.; Brown, W.D. & Miller, W.M.
Partner: UNT Libraries Government Documents Department

60-Day waste compatibility safety issues and final results for AY-102 grab samples

Description: Four grab samples (2AY-96-15, 2AY-96-16, 2AY-96-17, and 2AY-96-18) were taken from Riser 15D of Tank 241-AY-102 on October 8, 1996, and received by 222-S Laboratory on October 8, 1996. These samples were analyzed in accordance with Compatibility Grab Sampling and Analysis Plan (TSAP) and Data Quality Objectives for Tank Farms Waste Compatibility Program (DQO) in support of the Waste Compatibility Program. No notifications were required based on sample results.
Date: January 31, 1997
Creator: Nuzum, J.L.
Partner: UNT Libraries Government Documents Department

Materials Compatibility and Migration in Polymer Systems

Description: This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The purpose of this project to study the effects of materials migration by direct measurement of the diffusion and convective migration processes in complex polymeric materials and to develop appropriate predictive models. The use of isotopically tagged probe molecules to measure in-situ the diffusion of water in estane was demonstrated. A special environmental cell with a thin window was fabricated to enable real time measurements to be made under realistic conditions simulating actual operating parameters. Depth profiles were measured quantitatively using ion beam methods available at the Los Alamos Ion Beam Materials Laboratory. The Williams-Landau-Ferry model was adopted as a general expression for diffusion of a volatile material in a polymer. This model contains both thermal activation and free-volume change effects to account for the changes in polymeric structure with temperature and physical properties as embodied in the glass-transition temperature. A theoretical simulation of water migration in polyurethane was performed and compared to the ideal 1-D, constant temperature, constant-boundary concentration test problem, for which an analytical solution is known. The transport code works properly and indicates that time steps on the order of 10 minutes are permissible, which is the order of the time required to collect data for one measurement in the ion beam.
Date: July 10, 1999
Creator: Maggiore, C.J. & Valone, S.
Partner: UNT Libraries Government Documents Department

COMPLEXITY AT MESOSCALE

Description: Through three examples the authors illustrate some of the concepts and ingredients required for pattern formation at mesoscopic scales. Two examples built on microscopic models where mesoscopic patterns emerge from homogeneous ground states driven into instability by external forcing. In contrast, the third example builds on a mesoscopic phenomenological Ginzburg-Landan type model of solid-solid structural phase transition. Here, mesoscopic textures emerge as a result of competing length scales arising from the constraints of elastic compatibility.
Date: December 1, 2000
Creator: BISHOP, A.; RASMUSSEN, K. & AL, ET
Partner: UNT Libraries Government Documents Department

CRT compatibility evaluation of LX-16 and Halthane 73-18

Description: A preliminary compatibility study was carried out between the plastic-bonded PETN-based high explosive LX-16 and the adhesive Halthane 73-18. The work, based on the Chemical Reactivity Test (CRT), used non-standard times and temperatures to find conditions corresponding to accelerated decomposition. This study is a prequel to a more comprehensive isothermal and thermal cycling study that will include both material evaluation and test fire.
Date: August 24, 1999
Creator: Foltz, M F; Reyes, P & Foster, P A
Partner: UNT Libraries Government Documents Department