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Re-engineering Ethics: Pushing Philosophy Outside of its Comfort Zone at the APPE Annual Meeting (open access)

Re-engineering Ethics: Pushing Philosophy Outside of its Comfort Zone at the APPE Annual Meeting

This article discusses ethics and pushing philosophy outside of its comfort zone at the Association for Practical and Professional Ethics (APPE) annual meeting.
Date: March 27, 2013
Creator: Barr, Kelli R. & Lu, Wenlong
System: The UNT Digital Library
Coordination Chemistry of 4-Methyl-2,6,7-trioxa-1-phosphabicyclo[2,2,1]heptane: Preparation and Characterization of Ru(II) Complexes (open access)

Coordination Chemistry of 4-Methyl-2,6,7-trioxa-1-phosphabicyclo[2,2,1]heptane: Preparation and Characterization of Ru(II) Complexes

Article discussing preparation and characterization of Ru(II) complexes.
Date: March 27, 2012
Creator: Joslin, Evan E.; McMullin, Claire L.; Gunnoe, T. Brent; Cundari, Thomas R., 1964-; Sabat, Michal & Myers, William H.
System: The UNT Digital Library
Ultimate strength of carbon nanotubes: A theoretical study (open access)

Ultimate strength of carbon nanotubes: A theoretical study

Article on a theoretical study of the ultimate strength of carbon nanotubes.
Date: March 27, 2002
Creator: Zhao, Qingzhong; Buongiorno Nardelli, Marco & Bernholc, Jerry
System: The UNT Digital Library
Dynamic Conductance of Carbon Nanotubes (open access)

Dynamic Conductance of Carbon Nanotubes

Article on dynamic conductance of carbon nanotubes.
Date: March 27, 2000
Creator: Roland, Christopher; Buongiorno Nardelli, Marco; Wang, Jian & Guo, Hong
System: The UNT Digital Library
Nurse Aide Decision Making in Nursing Homes: Factors Affecting Empowerment (open access)

Nurse Aide Decision Making in Nursing Homes: Factors Affecting Empowerment

Article on nurse aide decision making in nursing homes and the factors affecting empowerment.
Date: March 27, 2013
Creator: Chaudhuri, Tanni & Yeatts, Dale E., 1952-
System: The UNT Digital Library
Solubility in Binary Solvent Mixtures: Anthracene Dissolved in Alcohol + Acetonitrile Mixtures at 298.2 K (open access)

Solubility in Binary Solvent Mixtures: Anthracene Dissolved in Alcohol + Acetonitrile Mixtures at 298.2 K

Article on the solubility in binary solvent mixtures and anthracene dissolved in alcohol + acetonitrile mixtures at 298.2 K.
Date: March 27, 2003
Creator: Monárrez, Cassandra I.; Woo, Jee H.; Taylor, Priscilla G.; Tran, Anh M. & Acree, William E. (William Eugene)
System: The UNT Digital Library
Energetic charged particle beams for disablement of mines (open access)

Energetic charged particle beams for disablement of mines

LLNL has an ongoing program of weapons disablement using energetic charged particle beams; this program combines theoretical and experimental expertise in accelerators, high-energy and nuclear physics, plasma physics and hydrodynamics to simulate/measure effects of electron and proton beams on weapons. This paper reviews work by LLNL, LANL and NSWC on detonating sensitive and insensitive high explosives and land mines using high-current electron beams. Computer simulations are given. 20--160 MeV electron beams incident on wet/dry soils are being studied, along with electron beam propagation in air. Compact high current, high energy accelerators are being developed for mine clearing. Countermine missions of interest are discussed. 25 refs., 9 figs.
Date: March 27, 1995
Creator: Wuest, C.R.
System: The UNT Digital Library
Efficient computation of periodic and nonperiodic Green`s functions in layered media using the MPIE (open access)

Efficient computation of periodic and nonperiodic Green`s functions in layered media using the MPIE

The mixed potential integral equation (MPIE) formulation is convenient for problems involving layered media because potential quantities involve low order singularities, in comparison to field quantities. For nonperiodic problems, the associated Green`s potentials involve spectral integrals of the Sommerfeld type, in the periodic case, discrete sums over sampled values of the same spectra are required. When source and observation points are in the same or in adjacent layers, the convergence of both representations is enhanced by isolating the direct and quasi-static image contributions associated with the nearby layers. In the periodic case, the convergence of direct and image contributions may be rapidly accelerated by means of the Ewadd method.
Date: March 27, 1998
Creator: Wilton, D. R.; Jackson, D. R. & Champagne, N. J.
System: The UNT Digital Library
Multilayer ultra high gradient insulator technology (open access)

Multilayer ultra high gradient insulator technology

We are investigating a novel insulator concept which involves the use of alternating layers of conductors and insulators with periods less than 1 mm. These structures perform many times better (about 1.5 to 4 times higher breakdown electric field) than conventional insulators in long pulse, short pulse, and alternating polarity applications. We present our ongoing studies investigating the degradation of the breakdown electric field resulting from surface roughness, the effect of gas pressure, and the performance of the insulator structure under bi-polar stress. Further, we present our initial modeling studies.
Date: March 27, 1998
Creator: Sampayan, S. E.; Vitello, P. A.; Krogh, M. L. & Elizondo, J. M.
System: The UNT Digital Library
The gene identification problem: An overview for developers (open access)

The gene identification problem: An overview for developers

The gene identification problem is the problem of interpreting nucleotide sequences by computer, in order to provide tentative annotation on the location, structure, and functional class of protein-coding genes. This problem is of self-evident importance, and is far from being fully solved, particularly for higher eukaryotes, Thus it is not surprising that the number of algorithm and software developers working in this area is rapidly increasing. The present paper is an overview of the field, with an emphasis on eukaryotes, for such developers.
Date: March 27, 1995
Creator: Fickett, J.W.
System: The UNT Digital Library
A comparison of interface tracking methods (open access)

A comparison of interface tracking methods

In this Paper we provide a direct comparison of several important algorithms designed to track fluid interfaces. In the process we propose improved criteria by which these methods are to be judged. We compare and contrast the behavior of the following interface tracking methods: high order monotone capturing schemes, level set methods, volume-of-fluid (VOF) methods, and particle-based (particle-in-cell, or PIC) methods. We compare these methods by first applying a set of standard test problems, then by applying a new set of enhanced problems designed to expose the limitations and weaknesses of each method. We find that the properties of these methods are not adequately assessed until they axe tested with flows having spatial and temporal vorticity gradients. Our results indicate that the particle-based methods are easily the most accurate of those tested. Their practical use, however, is often hampered by their memory and CPU requirements. Particle-based methods employing particles only along interfaces also have difficulty dealing with gross topology changes. Full PIC methods, on the other hand, do not in general have topology restrictions. Following the particle-based methods are VOF volume tracking methods, which are reasonably accurate, physically based, robust, low in cost, and relatively easy to implement. Recent enhancements …
Date: March 27, 1995
Creator: Kothe, D.B. & Rider, W. J.
System: The UNT Digital Library
Analysis of soil-structure interaction due to ambient vibration (open access)

Analysis of soil-structure interaction due to ambient vibration

This paper presents the results of a study to evaluate the effects of soil-structure interaction (SSI) on the ambient vibration response of the switchyard/target area (S/TA) buildings at the National Ignition Facility (NIF) presently under construction at the Lawrence Livermore National Laboratory (LLNL) in Livermore, California. This laser facility houses optical and other special equipment whose alignment stability is sensitive to vibrations caused by ambient vibrations or other vibrating sources. In evaluating the deformations and displacements of the S/TA structures, the contribution of the SSI to the overall system flexibility can be very significant. The present study examines the results of fixed-base and SSI analyses of these massive stiff structures to develop an understanding of the potential contribution of SSI to the overall system displacements and deformations. A simple procedure using a set of factors is recommended for scaling the results of fixed-base analyses to approximately account for SSI effects.
Date: March 27, 1998
Creator: Tabatabaie, M., Sommer, S.C.
System: The UNT Digital Library
Security services negotiation through OAM cells (open access)

Security services negotiation through OAM cells

As described in contribution AF99-0335, it is interesting that new security services and mechanisms are allowed to be negotiated during a connection in progress. To do that, new ''negotiation OAM cells'' dedicated to security should be defined, as well as some acknowledgment cells allowing negotiation OAM cells to be exchanged reliably. Remarks which were given at the New Orleans meeting regarding those cell formats are taken into account. This contribution presents some baseline text describing the format of the negotiation and acknowledgment cells, and the using of those cells. All the modifications brought to the specifications are reversible using the Word tools.
Date: March 27, 2000
Creator: LAURENT,MARYLINE & TARMAN,THOMAS D.
System: The UNT Digital Library
Automated analysis of failure event data (open access)

Automated analysis of failure event data

This paper focuses on fully automated analysis of failure event data in the concept and early development stage of a semiconductor-manufacturing tool. In addition to presenting a wide range of statistical and machine-specific performance information, algorithms have been developed to examine reliability growth and to identify major contributors to unreliability. These capabilities are being implemented in a new software package called Reliadigm. When coupled with additional input regarding repair times and parts availability, the analysis software also provides spare parts inventory optimization based on genetic optimization methods. The type of question to be answered is: If this tool were placed with a customer for beta testing, what would be the optimal spares kit to meet equipment reliability goals for the lowest cost? The new algorithms are implemented in Windows{reg_sign} software and are easy to apply. This paper presents a preliminary analysis of failure event data from three IDEA machines currently in development. The paper also includes an optimal spare parts kit analysis.
Date: March 27, 2000
Creator: Hennessy, Corey; Freerks, Fred; Campbell, James E. & Thompson, Bruce M.
System: The UNT Digital Library
Optical pulse generation using fiber lasers and integrated optics (open access)

Optical pulse generation using fiber lasers and integrated optics

We have demonstrated an optical pulse forming system using fiber and integrated optics, and have designed a multiple-output system for a proposed fusion laser facility. Our approach is an advancement over previous designs for fusion lasers, and an unusual application of fiber lasers and integrated optics.
Date: March 27, 1995
Creator: Wilcox, R. B.; Browning, D. F.; Burkhart, S. C. & VanWonterghem, B. W.
System: The UNT Digital Library
Mevva ion source operated in purely gaseous mode (open access)

Mevva ion source operated in purely gaseous mode

We have operated a vacuum arc ion source in such a way as to form beams of purely gaseous ions. The vacuum arc configuration that is conventionally used to produce intense beams of metal ions was altered so as to form gaseous ion beams, with only minimal changes to the external circuitry and no changes at all internally to the ion source. In our experiments we formed beams from oxygen (O{sup +} and O{sub 2}{sup +}), nitrogen (N{sup +} and N{sub 2}{sup +}), argon (Ar{sup +}) and carbon dioxide (C{sup +}, CO{sub 2}{sup +}, O{sup +} and O{sub 2}{sup +}) at extraction voltage of 2 to 50 kV. We used a pulsed mode of operation, with beam pulses approximately 50 milliseconds long and repetition rate 10 pulses per second, for a duty cycle of about 50%. Downstream ion beam current as measured by a 5 cm diameter Faraday cup was typically 0.5 mA pulse or about 250 {micro}A time averaged. This time averaged beam current is very similar to that obtained for metal ions when the source is operated in the usual vacuum arc mode. Here we describe the modifications made to the source and the results of our investigations.
Date: March 27, 2003
Creator: Yushkov, G.Y.; MacGill, R.A. & Brown, I. G.
System: The UNT Digital Library
Dimming Every Light Cheaply (open access)

Dimming Every Light Cheaply

This paper discusses the successful development and testing of the first ballast/IBECS network interface that will allow commercially-available controllable ballasts to be operated from the Internet via IBECS (Integrated Building Environmental Communications System). The interface, which is expected to cost original equipment manufacturers (OEMs) only about $1-2/unit, has been hardened so that it is impervious to electronic noise generated by most 0-10 VDC controllable ballasts.
Date: March 27, 2002
Creator: Rubinstein, Francis; Pettler, Peter & Jennings, Judith
System: The UNT Digital Library
Wingridder - an interactive grid generator for TOUGH2 (open access)

Wingridder - an interactive grid generator for TOUGH2

The TOUGH (Transport Of Unsaturated Groundwater and Heat) family of codes has great flexibility in handling the variety of grid information required to describe a complex subsurface system. However, designing and generating such a grid can be a tedious and error-prone process. This is especially true when the number of cells and connections is very large. As a user-friendly, efficient, and effective grid generating software, WinGridder has been developed for designing, generating, and visualizing (at various spatial scales) numerical grids used in reservoir simulations and groundwater modeling studies. It can save mesh files for TOUGH family codes. It can also output additional grid information for various purposes in either graphic format or plain text format. It has user-friendly graphical user interfaces, along with an easy-to-use interactive design and plot tools. Many important features, such as inclined faults and offset, layering structure, local refinements, and embedded engineering structures, can be represented in the grid.
Date: March 27, 2003
Creator: Pan, Lehua
System: The UNT Digital Library
Performance of the CDF Online Silicon Vertex Tracker (open access)

Performance of the CDF Online Silicon Vertex Tracker

The Online Silicon Vertex Tracker (SVT) is the new trigger processor dedicated to the 2-D reconstruction of charged particle trajectories at the Level 2 of the CDF trigger. The SVT links the digitized pulse heights found within the Silicon Vertex detector to the tracks reconstructed in the Central Outer Tracker by the Level 1 fast track finder. Preliminary tests of the system took place during the October 2000 commissioning run of the Tevatron Collider. During the April-October 2001 data taking it was possible to evaluate the performance of the system. In this paper we review the tracking algorithms implemented in the SVT and we report on the performance achieved during the early phase of run II.
Date: March 27, 2002
Creator: al., R. Carosi et
System: The UNT Digital Library
Estimation of fatigue crack initiation in austenitic stainless steels in LWR environments. (open access)

Estimation of fatigue crack initiation in austenitic stainless steels in LWR environments.

None
Date: March 27, 2002
Creator: Chopra, O. K.
System: The UNT Digital Library
Rotational hysteresis of exchange-spring magnets. (open access)

Rotational hysteresis of exchange-spring magnets.

We highlight our experimental studies and micromagnetic simulations of the rotational hysteresis in exchange-spring magnets. Magneto-optical imaging and torque magnetometry measurements for SmCo/Fe exchange-spring films with uniaxial in-plane anisotropy show that the magnetization rotation created in the magnetically soft Fe layer by a rotating magnetic field is hysteretic. The rotational hysteresis is due to the reversal of the chirality of the spin spiral structure. Micromagnetic simulations reveal two reversal modes of the chirality, one at low fields due to an in-plane untwisting of the spiral, and the other, at high fields, due to an out-of-plane fanning of the spiral.
Date: March 27, 2002
Creator: Jiang, J. S.; Bader, S. D.; Kaper, H.; Leaf, G. K.; Shull, R. D.; Shapiro, A. J. et al.
System: The UNT Digital Library
Mechanism of fatigue crack initiation in austenitic stainless steels in LWR environments. (open access)

Mechanism of fatigue crack initiation in austenitic stainless steels in LWR environments.

This paper examines the mechanism of fatigue crack initiation in austenitic stainless steels (SSs) in light water reactor (LWR) coolant environments. The effects of key material and loading variables, such as strain amplitude, strain rate, temperature, level of dissolved oxygen in water, and material heat treatment on the fatigue lives of wrought and cast austenitic SSs in air and LWR environments have been evaluated. The influence of reactor coolant environments on the formation and growth of fatigue cracks in polished smooth SS specimens is discussed. Crack length as a function of fatigue cycles was determined in air and LWR environments. The results indicate that decreased fatigue lives of these steels are caused primarily by the effects of the environment on the growth of cracks <200 {micro}m and, to a lesser extent, on enhanced growth rates of longer cracks. A detailed metallographic examination of fatigue test specimens was performed to characterize the fracture morphology. Exploratory fatigue tests were conducted to enhance our understanding of the effects of surface micropits or minor differences in the surface oxide on fatigue crack initiation.
Date: March 27, 2002
Creator: Chopra, O. K.
System: The UNT Digital Library
Case Study: The ''Office of Real Soon Now'' for Visualization (open access)

Case Study: The ''Office of Real Soon Now'' for Visualization

A variation on the ''Office of Real Soon Now'' has been designed and deployed at Lawrence Livermore National Laboratory (LLNL). The ASCI VIEWS (VIEWS) program [1], the element of the program developing tools for data management and visualization, is investigating a variety of display technologies, motivated in part by the large size, high resolution, and complexity of data sets that ASCI users frequently explore and analyze. While large, tiled displays have been well received at LLNL, availability and ease-of-use problems have motivated exploration of alternatives [2]. The ''Office of Real Soon Now'' Project [3, 4, 5] at the University of North Carolina at Chapel Hill (UNC) has built ''low fidelity'' versions of the ''Office of the Future'' [6, 7] that can be installed in users' offices now. At UNC, the Office of Real Soon Now installations use only a small number of relatively inexpensive projectors,generally two or three, that limit resolution and features. These projectors are connected to Microsoft Windows PCs or Apple computers that are used for daily activities, such as reading email, writing papers, and debugging programs. Even though the UNC faculty involved are predominantly computer graphics researchers, these display systems are used mainly for text-oriented applications [5]. …
Date: March 27, 2002
Creator: Uselton, S.P.
System: The UNT Digital Library
Finite Element Output Bounds for Hyperbolic Problems (open access)

Finite Element Output Bounds for Hyperbolic Problems

We propose a Neumann-subproblem a posteriori finite element error bound technique for linear stationary scalar advection problems. The method is similar in many respects to the previous output bound technique developed for elliptic problems. In the new approach, however, the primal residual is enhanced with a streamline diffusion term. We first formulate the bound algorithm, with particular emphasis on the proof of the bounding properties; then, we provide numerical results for an illustrative example.
Date: March 27, 2000
Creator: Machiels, L.
System: The UNT Digital Library