A Testing Platform for Validation of Overhead Conductor Aging Models and Understanding Thermal Limits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Irminger, Philip; Starke, Michael R; Dimitrovski, Aleksandar D

2014-01-01

Power system equipment manufacturers and researchers continue to experiment with novel overhead electric conductor designs that support better conductor performance and address congestion issues. To address the technology gap in testing these novel designs, Oak Ridge National Laboratory constructed the Powerline Conductor Accelerated Testing (PCAT) facility to evaluate the performance of novel overhead conductors in an accelerated fashion in a field environment. Additionally, PCAT has the capability to test advanced sensors and measurement methods for accessing overhead conductor performance and condition. Equipped with extensive measurement and monitoring devices, PCAT provides a platform to improve/validate conductor computer models and assess themore » performance of novel conductors. The PCAT facility and its testing capabilities are described in this paper.« less

Conductors for commercial MRI magnets beyond NbTi: requirements and challenges.

PubMed

Parizh, Michael; Lvovsky, Yuri; Sumption, Michael

2017-01-01

Magnetic Resonance Imaging (MRI), a powerful medical diagnostic tool, is the largest commercial application of superconductivity. The superconducting magnet is the largest and most expensive component of an MRI system. The magnet configuration is determined by competing requirements including optimized functional performance, patient comfort, ease of siting in a hospital environment, minimum acquisition and lifecycle cost including service. In this paper, we analyze conductor requirements for commercial MRI magnets beyond traditional NbTi conductors, while avoiding links to a particular magnet configuration or design decisions. Potential conductor candidates include MgB 2 , ReBCO and BSCCO options. The analysis shows that no MRI-ready non-NbTi conductor is commercially available at the moment. For some conductors, MRI specifications will be difficult to achieve in principle. For others, cost is a key barrier. In some cases, the prospects for developing an MRI-ready conductor are more favorable, but significant developments are still needed. The key needs include the development of, or significant improvements in: (a) conductors specifically designed for MRI applications, with form-fit-and-function readily integratable into the present MRI magnet technology with minimum modifications. Preferably, similar conductors should be available from multiple vendors; (b) conductors with improved quench characteristics, i.e. the ability to carry significant current without damage while in the resistive state; (c) insulation which is compatible with manufacturing and refrigeration technologies; (d) dramatic increases in production and long-length quality control, including large-volume conductor manufacturing technology. In-situ MgB 2 is, perhaps, the closest to meeting commercial and technical requirements to become suitable for commercial MRI. Conductor technology is an important, but not the only, issue in introduction of HTS / MgB 2 conductor into commercial MRI magnets. These new conductors, even when they meet the above requirements, will likely require numerous modifications and developments in the associated magnet technology.

Conductors for commercial MRI magnets beyond NbTi: requirements and challenges

NASA Astrophysics Data System (ADS)

Parizh, Michael; Lvovsky, Yuri; Sumption, Michael

2017-01-01

Magnetic resonance imaging (MRI), a powerful medical diagnostic tool, is the largest commercial application of superconductivity. The superconducting magnet is the largest and most expensive component of an MRI system. The magnet configuration is determined by competing requirements including optimized functional performance, patient comfort, ease of siting in a hospital environment, minimum acquisition and lifecycle cost including service. In this paper, we analyze conductor requirements for commercial MRI magnets beyond traditional NbTi conductors, while avoiding links to a particular magnet configuration or design decisions. Potential conductor candidates include MgB2, ReBCO and BSCCO options. The analysis shows that no MRI-ready non-NbTi conductor is commercially available at the moment. For some conductors, MRI specifications will be difficult to achieve in principle. For others, cost is a key barrier. In some cases, the prospects for developing an MRI-ready conductor are more favorable, but significant developments are still needed. The key needs include the development of, or significant improvements in: (a) conductors specifically designed for MRI applications, with form-fit-and-function readily integratable into the present MRI magnet technology with minimum modifications. Preferably, similar conductors should be available from multiple vendors; (b) conductors with improved quench characteristics, i.e. the ability to carry significant current without damage while in the resistive state; (c) insulation which is compatible with manufacturing and refrigeration technologies; (d) dramatic increases in production and long-length quality control, including large-volume conductor manufacturing technology. In-situ MgB2 is, perhaps, the closest to meeting commercial and technical requirements to become suitable for commercial MRI. Conductor technology is an important, but not the only, issue in introduction of HTS/MgB2 conductor into commercial MRI magnets. These new conductors, even when they meet the above requirements, will likely require numerous modifications and developments in the associated magnet technology.

Conductors for commercial MRI magnets beyond NbTi: requirements and challenges

PubMed Central

Parizh, Michael; Lvovsky, Yuri; Sumption, Michael

2016-01-01

Magnetic Resonance Imaging (MRI), a powerful medical diagnostic tool, is the largest commercial application of superconductivity. The superconducting magnet is the largest and most expensive component of an MRI system. The magnet configuration is determined by competing requirements including optimized functional performance, patient comfort, ease of siting in a hospital environment, minimum acquisition and lifecycle cost including service. In this paper, we analyze conductor requirements for commercial MRI magnets beyond traditional NbTi conductors, while avoiding links to a particular magnet configuration or design decisions. Potential conductor candidates include MgB2, ReBCO and BSCCO options. The analysis shows that no MRI-ready non-NbTi conductor is commercially available at the moment. For some conductors, MRI specifications will be difficult to achieve in principle. For others, cost is a key barrier. In some cases, the prospects for developing an MRI-ready conductor are more favorable, but significant developments are still needed. The key needs include the development of, or significant improvements in: (a) conductors specifically designed for MRI applications, with form-fit-and-function readily integratable into the present MRI magnet technology with minimum modifications. Preferably, similar conductors should be available from multiple vendors; (b) conductors with improved quench characteristics, i.e. the ability to carry significant current without damage while in the resistive state; (c) insulation which is compatible with manufacturing and refrigeration technologies; (d) dramatic increases in production and long-length quality control, including large-volume conductor manufacturing technology. In-situ MgB2 is, perhaps, the closest to meeting commercial and technical requirements to become suitable for commercial MRI. Conductor technology is an important, but not the only, issue in introduction of HTS / MgB2 conductor into commercial MRI magnets. These new conductors, even when they meet the above requirements, will likely require numerous modifications and developments in the associated magnet technology. PMID:28626340

[Measurement of the electric field of the heart in a homogeneous volume conductor].

PubMed

Tsukerman, B M; Titomir, L I

1975-01-01

The paper describes a technique and some results of experimental measurements of electrical potentials generated by an isolated dog heart in homogeneous conductor, drawing equipotential maps of the field, and calculating the characteristics of the dipole equivalent generator of the heart. The form of potential distribution on a spherical surface around the heart and its ideal orthogonal vectorcardiograms are discussed.

Modelling Near-Surface Metallic Clutter Without the Excruciating Pain

NASA Astrophysics Data System (ADS)

Downs, C. M.; Weiss, C. J.; Bach, J.; Williams, J. T.

2016-12-01

An ongoing problem in modeling electromagnetic (EM) interactions with the near-surface and related anthropogenic metal clutter is the large difference in length scale between the clutter dimensions and their resulting EM response. For example, observational evidence shows that cables, pipes and rail lines can have a strong influence far from where they are located, even in situations where these artefacts are volumetrically insignificant over the scale of the model. This poses a significant modeling problem for understanding geohazards in urban environments, for example, because of the very fine numerical discretization required for accurate representation of an artefact embedded in a larger computational domain. We adopt a sub-grid approximation and impose a boundary condition along grid edges to capture the vanishing fields of a perfect conductor. We work in a Cartesian system where the EM fields are solved via finite volumes in the frequency domain in terms of the Lorenz gauged magnetic vector (A) and electric scalar (Phi) potentials. The electric fied is given simply by A-grad(Phi), and set identically to zero along edges of the mesh that coincide with the center of long, slender metallic conductors. A simple extension to bulky artefacts like blocks or slabs involves endowing all such edges in their interior with the same "internal" boundary condition. In essence, we apply the "perfect electric conductor" boundary condition to select edges interior to the modeling domain. We note a few minor numerical consequences of this approach, namely: the zero-E field internal boundary condition destroys the symmetry of the finite volume coefficient matrix; and, the accuracy of the representation of the conducting artefact is restricted by the relatively coarse discretization mesh. The former is overcome with the use of preconditioned bi-conjugate gradient methods instead of the quasi-minimal-residual method. Both are matrix-free iterative solvers - thus avoiding unnecessary storage- and both exhibit generally good convergence for well-posed problems. The latter is more difficult to overcome without either modifying the mesh (potentially degrading the condition number of the coefficient matrix) or with novel mesh sub-gridding. Initial results show qualitative agreement with the expected physics.

A Mathematical Evaluation of the Core Conductor Model

PubMed Central

Clark, John; Plonsey, Robert

1966-01-01

This paper is a mathematical evaluation of the core conductor model where its three dimensionality is taken into account. The problem considered is that of a single, active, unmyelinated nerve fiber situated in an extensive, homogeneous, conducting medium. Expressions for the various core conductor parameters have been derived in a mathematically rigorous manner according to the principles of electromagnetic theory. The purpose of employing mathematical rigor in this study is to bring to light the inherent assumptions of the one dimensional core conductor model, providing a method of evaluating the accuracy of this linear model. Based on the use of synthetic squid axon data, the conclusion of this study is that the linear core conductor model is a good approximation for internal but not external parameters. PMID:5903155

A New Pulse Shape to Obtain Selective Small Fiber Activation by Anodal Blocking

DTIC Science & Technology

2001-10-25

anodal blocking a tripolar cuff electrode is most commonly used. When external stimulation is applied, the fiber membrane is depolarized close to...would be safer if somehow the charge per phase could be reduced. Charge reduction might be possible with the following idea: In a tripolar cuff...inhomogeneous and anisotropic volume conductor model [3]. A symmetrical tripolar cuff electrode with an inner diameter of 2 mm was placed around a

Research@ARL: Materials Modeling at Multiple Scales. Volume 3, Issue 2

DTIC Science & Technology

2014-07-01

possessing high ionic conductivity , low viscosity, and good thermal and electrochemical stability and, importantly, being compatible with electrodes. As... thermal and electrical properties. ARL conducts extensive research in graphene and other 2D materials such as BN, ZnO, and hybrid graphene-polyethylene...contribution at temperatures below 393 K. Thus, below 393 K, Li2EDC essentially acts as a single ion conductor . The isotropic ionic conductivity from MD

Skin Effect Modeling in Conductors of Arbitrary Shape Through a Surface Admittance Operator and the Contour Integral Method

NASA Astrophysics Data System (ADS)

Patel, Utkarsh R.; Triverio, Piero

2016-09-01

An accurate modeling of skin effect inside conductors is of capital importance to solve transmission line and scattering problems. This paper presents a surface-based formulation to model skin effect in conductors of arbitrary cross section, and compute the per-unit-length impedance of a multiconductor transmission line. The proposed formulation is based on the Dirichlet-Neumann operator that relates the longitudinal electric field to the tangential magnetic field on the boundary of a conductor. We demonstrate how the surface operator can be obtained through the contour integral method for conductors of arbitrary shape. The proposed algorithm is simple to implement, efficient, and can handle arbitrary cross-sections, which is a main advantage over the existing approach based on eigenfunctions, which is available only for canonical conductor's shapes. The versatility of the method is illustrated through a diverse set of examples, which includes transmission lines with trapezoidal, curved, and V-shaped conductors. Numerical results demonstrate the accuracy, versatility, and efficiency of the proposed technique.

Analysis of Lightning-induced Impulse Magnetic Fields in the Building with an Insulated Down Conductor

NASA Astrophysics Data System (ADS)

Du, Patrick Y.; Zhou, Qi-Bin

This paper presents an analysis of lightning-induced magnetic fields in a building. The building of concern is protected by the lightning protection system with an insulated down conductor. In this paper a system model for metallic structure of the building is constructed first using the circuit approach. The circuit model of the insulated down conductor is discussed extensively, and explicit expressions of the circuit parameters are presented. The system model was verified experimentally in the laboratory. The modeling approach is applied to analyze the impulse magnetic fields in a full-scale building during a direct lightning strike. It is found that the impulse magnetic field is significantly high near the down conductor. The field is attenuated if the down conductor is moved to a column in the building. The field can be reduced further if the down conductor is housed in an earthed metal pipe. Recommendations for protecting critical equipment against lightning-induced magnetic fields are also provided in the paper.

Generalized Fluid System Simulation Program, Version 5.0-Educational. Supplemental Information for NASA/TM-2011-216470. Supplement

NASA Technical Reports Server (NTRS)

Majumdar, A. K.

2011-01-01

The Generalized Fluid System Simulation Program (GFSSP) is a finite-volume based general-purpose computer program for analyzing steady state and time-dependent flow rates, pressures, temperatures, and concentrations in a complex flow network. The program is capable of modeling real fluids with phase changes, compressibility, mixture thermodynamics, conjugate heat transfer between solid and fluid, fluid transients, pumps, compressors and external body forces such as gravity and centrifugal. The thermofluid system to be analyzed is discretized into nodes, branches, and conductors. The scalar properties such as pressure, temperature, and concentrations are calculated at nodes. Mass flow rates and heat transfer rates are computed in branches and conductors. The graphical user interface allows users to build their models using the point, drag and click method; the users can also run their models and post-process the results in the same environment. The integrated fluid library supplies thermodynamic and thermo-physical properties of 36 fluids and 21 different resistance/source options are provided for modeling momentum sources or sinks in the branches. This Technical Memorandum illustrates the application and verification of the code through 12 demonstrated example problems. This supplement gives the input and output data files for the examples.

Development of termination and utilization concepts for flat conductor cables. Volume 2: Utilization of small gage wire round conductor cables

NASA Technical Reports Server (NTRS)

1972-01-01

The practical use of small-gage round wire for electrical wiring in manned air and space vehicle environments is discussed. The investigation consisted on a study of wire construction and candidate wire harness concepts, fabrication of small-gage wire harnesses, and verification of promising configurations by laboratory evaluation. The wire constructions selected for harness fabrication are described. Results of the laboratory evaluation are included.

Modeling the electrical resistance of gold film conductors on uniaxially stretched elastomeric substrates

NASA Astrophysics Data System (ADS)

Cao, Wenzhe; Görrn, Patrick; Wagner, Sigurd

2011-05-01

The electrical resistance of gold film conductors on polydimethyl siloxane substrates at stages of uniaxial stretching is measured and modeled. The surface area of a gold conductor is assumed constant during stretching so that the exposed substrate takes up all strain. Sheet resistances are calculated from frames of scanning electron micrographs by numerically solving for the electrical potentials of all pixels in a frame. These sheet resistances agree sufficiently well with values measured on the same conductors to give credence to the model of a stretchable network of gold links defined by microcracks.

Free Molecular Heat Transfer Programs for Setup and Dynamic Updating the Conductors in Thermal Desktop

NASA Technical Reports Server (NTRS)

Malroy, Eric T.

2007-01-01

The programs, arrays and logic structure were developed to enable the dynamic update of conductors in thermal desktop. The MatLab program FMHTPRE.m processes the Thermal Desktop conductors and sets up the arrays. The user needs to manually copy portions of the output to different input regions in Thermal Desktop. Also, Fortran subroutines are provided that perform the actual updates to the conductors. The subroutines are setup for helium gas, but the equations can be modified for other gases. The maximum number of free molecular conductors allowed is 10,000 for a given radiation task. Additional radiation tasks for FMHT can be generated to account for more conductors. Modifications to the Fortran subroutines may be warranted, when the mode of heat transfer is in the mixed or continuum mode. The FMHT Thermal Desktop model should be activated by using the "Case Set Manager" once the model is setup. Careful setup of the model is needed to avoid excessive solve times.

Fabrication and modeling of stretchable conductors for traumatic brain injury research

NASA Astrophysics Data System (ADS)

Cao, Wenzhe

Stretchable electronics are an emergent class of electronics that can retain their electric functionality under large mechanical deformation, such as stretching, bending and compression. Like traditional electric circuits, stretchable electronics rely on electrical conductors, but in this specific instance the conductors must also be stretchable. This thesis research had three goals: (1) fabricate elastically stretchable conductors that retain their electrical conductance when stretched by tens of percent of strain; (2) understand the underlying stretching mechanism of gold conductors on polydimethylsiloxane (PDMS) substrates; (3) produce a special device---a stretchable microelectrode array, which contains a matrix of stretchable conductors that enables a new approach to studying traumatic brain injury. We first developed and optimized the micro-fabrication process to make elastically stretchable thin gold film conductors on PDMS substrates. The conductors can retain electrical conduction while being stretched reversibly to 140% uniaxially and 16% radially. We further developed a fabrication process to encapsulate the conductors with either a commercially available photopatternable silicone (PPS) or with PDMS. 100 microm by 100 microm vias were patterned in the encapsulation layer to expose electrical contacts. PPS encapsulated conductors can be stretched uniaxially to 80%, and the PDMS encapsulated conductor can be stretched to ˜15%, without losing electrical conduction. We also introduced acrylate-based shape memory polymers (SMPs) as a new type of substrate for stretchable conductors. Their stiffness can be tuned by varying the monomer composition or by changing the ambient temperature. Thin gold film conductors deposited on pre-strained SMPs remain conductive when first stretched and then relaxed to their pre-strain value. Moreover, an SMP can also serve as a stretchable carrier to make pre-strained conductors on an overlying PDMS membrane. The resistance of gold conductors made on pre-strained PDMS changes less during stretching than that made on non-pre-strained PDMS substrate. We built a model of the electrical resistance in function of strain. The model is based on the topography of the thin gold film on PDMS. This model is a first attempt at predicting electrical resistance of stretchable thin gold film conductors. Lastly, we fabricated stretchable microelectrode arrays (SMEAs). They were utilized at Columbia University to study traumatic brain injury (TBI). Tissues cultured on SMEA remained viable for 19 days, and the electrodes were able to both stimulate and record neural tissue activity before, during and after stretching. Therefore SMEAs are able to bring together mechanical injury, electrophysiological recording and pharmacological studies. The SMEAs could serve as in vitro platforms for high throughput therapeutic screening and discovery for traumatic injury. The ability to reproducibly fabricate stretchable conductors using micro-fabrication technology will facilitate adoption by industry. The ability to understand the stretching mechanism will enable us to design more robust material systems. The SMEA prototypes demonstrate that stretchable conductors are practical, and their mechanical compatibility with biological systems also makes them candidates for use in biomedical devices.

Study on galloping behavior of iced eight bundle conductor transmission lines

NASA Astrophysics Data System (ADS)

Zhou, Linshu; Yan, Bo; Zhang, Liang; Zhou, Song

2016-02-01

Wind tunnel test was carried out to obtain the aerodynamic coefficients of an eight bundle conductor accreted with crescent-shaped ice. A user-defined cable element with torsional degree of freedom is developed in ABAQUS software to capture the torsional deformation of the iced conductors during galloping. By means of the user-defined cable element, different damping ratios in in-plane, out-of-plane and torsional directions of the conductors can be defined and the aerodynamic forces varying with their motion status can be exerted on the conductors conveniently when ABAQUS is used to simulate galloping of transmission lines. A wind tunnel test to model galloping of an iced eight bundle conductor segment was carried out, and the validity of the numerical simulation method is demonstrated by the agreement of the galloping orbit of the bundle conductor segment model recorded in the test and that by the numerical simulation. Furthermore, galloping behavior, including dynamic responses, galloping orbits, frequencies, vibration modes and amplitudes, of typical iced eight bundle conductor transmission lines in the cases of different span lengths, initial tensions in sub-conductors, wind velocities, angles of wind attack and damping ratios is studied, and the galloping behavior of the lines with internal resonance conditions is discussed. The obtained results may provide a fundamental tool for the development of anti-galloping techniques of eight bundle conductor transmission lines.

A new percolation model for composite solid electrolytes and dispersed ionic conductors

NASA Astrophysics Data System (ADS)

Risyad Hasyim, Muhammad; Lanagan, Michael T.

2018-02-01

Composite solid electrolytes (CSEs) including conductor/insulator composites known as dispersed ionic conductors (DICs) have motivated the development of novel percolation models that describe their conductivity. Despite the long history, existing models lack in one or more key areas: (1) rigorous foundation for their physical theory, (2) explanation for non-universal conductor-insulator transition, (3) classification of DICs, and (4) extension to frequency-domain. This work describes a frequency-domain effective medium approximation (EMA) of a bond percolation model for CSEs. The EMA is derived entirely from Maxwell’s equations and contains basic microstructure parameters. The model was applied successfully to several composite systems from literature. Simulations and fitting of literature data address these key areas and illustrate the interplay between space charge layer properties and bulk microstructure.

Effect of conductor geometry on source localization: Implications for epilepsy studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlitt, H.; Heller, L.; Best, E.

1994-07-01

We shall discuss the effects of conductor geometry on source localization for applications in epilepsy studies. The most popular conductor model for clinical MEG studies is a homogeneous sphere. However, several studies have indicated that a sphere is a poor model for the head when the sources are deep, as is the case for epileptic foci in the mesial temporal lobe. We believe that replacing the spherical model with a more realistic one in the inverse fitting procedure will improve the accuracy of localizing epileptic sources. In order to include a realistic head model in the inverse problem, we mustmore » first solve the forward problem for the realistic conductor geometry. We create a conductor geometry model from MR images, and then solve the forward problem via a boundary integral equation for the electric potential due to a specified primary source. One the electric potential is known, the magnetic field can be calculated directly. The most time-intensive part of the problem is generating the conductor model; fortunately, this needs to be done only once for each patient. It takes little time to change the primary current and calculate a new magnetic field for use in the inverse fitting procedure. We present the results of a series of computer simulations in which we investigate the localization accuracy due to replacing the spherical model with the realistic head model in the inverse fitting procedure. The data to be fit consist of a computer generated magnetic field due to a known current dipole in a realistic head model, with added noise. We compare the localization errors when this field is fit using a spherical model to the fit using a realistic head model. Using a spherical model is comparable to what is usually done when localizing epileptic sources in humans, where the conductor model used in the inverse fitting procedure does not correspond to the actual head.« less

Development of termination and utilization concepts for flat conductor cables. Volume 1: Development of low profile flat conductor cable connecting device and permanent splice

NASA Technical Reports Server (NTRS)

1972-01-01

The development of low-profile flat conductor cable (FCC) connecting device and FCC permanent splice methods are discussed. The design goal for the low-profile connecting device was to mate and unmate FCC harness to a typical spacecraft component with a maximum height of 3/8 in. The results indicate that the design, fabrication, and processing of the low-profile connecting device are feasible and practical. Some redesign will be required to achieve the goal of 3/8 in. Also, failures were experienced subsequent to salt spray and humidity exposure. Five different FCC permanent splice methods were considered. Subsequent to evaluation of these five methods, two design concepts were chosen for development tests.

Extraction of MOS VLSI (Very-Large-Scale-Integrated) Circuit Models Including Critical Interconnect Parasitics.

DTIC Science & Technology

1987-09-01

can be reduced substantially, compared to using numerical methods to model inter - " connect parasitics. Although some accuracy might be lost with...conductor widths and spacings listed in Table 2 1 , have been employed for simulation. In the first set of the simulations, planar dielectric inter ...model, there are no restrictions on the iumber ol diele-iric and conductors. andl the shape of the conductors and the dielectric inter - a.e,, In the

Water-level sensor and temperature-profile detector

DOEpatents

Not Available

1981-01-29

A temperature profile detector is described which comprises a surrounding length of metal tubing and an interior electrical conductor both constructed of high temperature high electrical resistance materials. A plurality of gas-filled expandable bellows made of electrically conductive material are positioned at spaced locations along a length of the conductors. The bellows are sealed and contain a predetermined volume of a gas designed to effect movement of the bellows from an open circuit condition to a closed circuit condition in response to monitored temperature changes sensed by each bellows.

Water level sensor and temperature profile detector

DOEpatents

Tokarz, Richard D.

1983-01-01

A temperature profile detector comprising a surrounding length of metal tubing and an interior electrical conductor both constructed of high temperature high electrical resistance materials. A plurality of gas-filled expandable bellows made of electrically conductive material is electrically connected to the interior electrical conductor and positioned within the length of metal tubing. The bellows are sealed and contain a predetermined volume of a gas designed to effect movement of the bellows from an open circuit condition to a closed circuit condition in response to monitored temperature changes sensed by each bellows.

Flat conductor cable for electrical packaging

NASA Technical Reports Server (NTRS)

Angele, W.

1972-01-01

Flat conductor cable (FCC) is relatively new, highly promising means for electrical packaging and system integration. FCC offers numerous desirable traits (weight, volume and cost savings, flexibility, high reliability, predictable and repeatable electrical characteristics) which make it extremely attractive as a packaging medium. FCC, today, finds wide application in everything from integration of lunar equipment to the packaging of electronics in nuclear submarines. Described are cable construction and means of termination, applicable specifications and standards, and total FCC systems. A list of additional sources of data is also included for more intensive study.

Practical fit functions for transport critical current versus field magnitude and angle data from (RE)BCO coated conductors at fixed low temperatures and in high magnetic fields

NASA Astrophysics Data System (ADS)

Hilton, D. K.; Gavrilin, A. V.; Trociewitz, U. P.

2015-07-01

Applications of (RE = Y, Gd)BCO coated conductors for the generation of high magnetic fields are increasing sharply, this while (RE)BCO coated conductors themselves are evolving rapidly. This article describes and demonstrates recently developed and applied mathematical models that systematically and comprehensively characterize the transport critical current angular dependence of a batch of (RE)BCO coated conductor in high magnetic fields at fixed temperatures with an uncertainty of 10% or better. The model development was based on analysis of experimental data sets from various published sources and coated conductors with different microstructures. These derivations directly are applicable to the accurate prediction of the performance in high magnetic fields of coils wound with (RE)BCO coated conductors. In particular, a nonlinear fit is discussed in this article of transport critical current at T = 4.2 K versus field and angle data. This fit was used to estimate the hysteresis losses of (RE)BCO coated conductors in high magnetic fields, and to design the inserts wound with such conductors of the all-superconducting 32 T magnet being constructed at the NHMFL. A series of such fits, recently developed at several fixed temperatures, continues to be used to simulate the quench behavior of that magnet.

Professional Orchestral Conductors' Use of Selected Teaching Behaviors in Rehearsal

ERIC Educational Resources Information Center

Whitaker, Jennifer A.

2017-01-01

This descriptive study examined professional conductors' use of rehearsal time in sequential pattern components, discussing task presentation targets, and using verbal imagery and modeling techniques. Commercially available videos of 15 professional conductors rehearsing prominent orchestras were scripted, coded, and timed for selected teaching…

Features of a SINDA/FLUINT model of a liquid oxygen supply line

NASA Astrophysics Data System (ADS)

Simmonds, Boris G.

1993-11-01

The modeling features used in a steady-state heat transfer problem using SINDA/FLUINT are described. The problem modeled is a 125 feet long, 3 inch diameter pipe, filled with liquid oxygen flow driven by a given pressure gradient. The pipe is fully insulated in five sections. Three sections of 1 inch thick spray-on foam and two sections of vacuum jacket. The model evaluates friction, turns losses and convection heat transfer between the fluid and the pipe wall. There is conduction through the foam insulation with temperature dependent thermal conductivity. The vacuum space is modeled with radiation and gas molecular conduction, if present, in the annular gap. Heat is transferred between the outer surface and surrounding ambient by natural convection and radiation; and, by axial conduction along the pipe and through the vacuum jacket spacers and welded seal flanges. The model makes extensive use of SINDA/FLUINT basic capabilities such as the GEN option for nodes and conductors (to generate groups of nodes or conductors), the SIV option (to generate single, temperature varying conductors), the SIM option (for multiple, temperature varying conductors) and the M HX macros for fluids (to generate strings of lumps, paths, and ties representing a diabatic duct). It calls subroutine CONTRN (returns the relative location in the G-array of a network conductor, given an actual conductor number) enabling an extensive manipulation of conductor (calculates an assignment of their values) with DO loops. Models like this illustrate to the new and even to the old SINDA/FLUINT user, features of the program that are not so obvious or known, and that are extremely handy when trying to take advantage of both, the automation of the DATA headers and make surgical modifications to specific parameters of the thermal or fluid elements in the OPERATIONS portion of the model.

Features of a SINDA/FLUINT model of a liquid oxygen supply line

NASA Technical Reports Server (NTRS)

Simmonds, Boris G.

1993-01-01

The modeling features used in a steady-state heat transfer problem using SINDA/FLUINT are described. The problem modeled is a 125 feet long, 3 inch diameter pipe, filled with liquid oxygen flow driven by a given pressure gradient. The pipe is fully insulated in five sections. Three sections of 1 inch thick spray-on foam and two sections of vacuum jacket. The model evaluates friction, turns losses and convection heat transfer between the fluid and the pipe wall. There is conduction through the foam insulation with temperature dependent thermal conductivity. The vacuum space is modeled with radiation and gas molecular conduction, if present, in the annular gap. Heat is transferred between the outer surface and surrounding ambient by natural convection and radiation; and, by axial conduction along the pipe and through the vacuum jacket spacers and welded seal flanges. The model makes extensive use of SINDA/FLUINT basic capabilities such as the GEN option for nodes and conductors (to generate groups of nodes or conductors), the SIV option (to generate single, temperature varying conductors), the SIM option (for multiple, temperature varying conductors) and the M HX macros for fluids (to generate strings of lumps, paths, and ties representing a diabatic duct). It calls subroutine CONTRN (returns the relative location in the G-array of a network conductor, given an actual conductor number) enabling an extensive manipulation of conductor (calculates an assignment of their values) with DO loops. Models like this illustrate to the new and even to the old SINDA/FLUINT user, features of the program that are not so obvious or known, and that are extremely handy when trying to take advantage of both, the automation of the DATA headers and make surgical modifications to specific parameters of the thermal or fluid elements in the OPERATIONS portion of the model.

Recent Progress of the Series-Connected Hybrid Magnet Projects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adkins, Todd; Bole, Scott

2010-01-01

The National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida has designed and is now constructing two Series Connected Hybrid (SCH) magnets, each connecting a superconducting outsert coil and a resistive Florida Bitter insert coil electrically in series. The SCH to be installed at the NHMFL will produce 36 T and provide 1 ppm maximum field inhomogeneity over a 1 cm diameter spherical volume. The SCH to be installed at the Helmholtz Center Berlin (HZB) in combination with a neutron source will produce 25 T to 30 T depending on the resistive insert. The two magnets have a common designmore » for their cable-in-conduit conductor (CICC) and superconducting outsert coils. The CICC outsert coil winding packs have an inner diameter of 0.6 m and contribute 13.1 T to the central field using three grades of CICC conductors. Each conductor grade carries 20 kA and employs the same type of Nb{sub 3}Sn superconducting wire, but each grade contains different quantities of superconducting wires, different cabling patterns and different aspect ratios. The cryostats and resistive insert coils for the two magnets are different. This paper discusses the progress in CIC conductor and coil fabrication over the last year including specification, qualification and production activities for wire, cable, conductor and coil processing.« less

Manufacturing and quality control of interconnecting wire harnesses, Volume 4

NASA Technical Reports Server (NTRS)

1972-01-01

The document covers interconnecting wire harnesses defined in the design standard, including type 8, flat conductor cable. Volume breadth covers installations of groups of harnesses in a major assembly and the associated post installation inspections and electrical tests. Knowledge gained through experience on the Saturn 5 program coupled with recent advances in techniques, materials, and processes was incorporated into this document.

Magnet Design with High B0 Homogeneity for Fast-Field-Cycling NMR Applications

NASA Astrophysics Data System (ADS)

Lips, O.; Privalov, A. F.; Dvinskikh, S. V.; Fujara, F.

2001-03-01

The design, construction, and performance of a low-inductance solenoidal coil with high B0 homogeneity for fast-field-cycling NMR is presented. It consists of six concentric layers. The conductor width is varied to minimize the B0 inhomogeneity in the volume of the sample. This is done using an algorithm which takes the real shape of the conductor directly into account. The calculated coil geometry can be manufactured easily using standard computerized numeric control equipment, which keeps the costs low. The coil is liquid cooled and produces a B0 field of 0.95 T at 800 A . The field inhomogeneity in a cylindrical volume (diameter 5 mm, length 10 mm) is about 10 ppm, and the inductance is 190 μH. Switching times below 200 μs can be achieved. During 6 months of operation the coil has shown good stability and reliability.

Performance analysis of radiation cooled dc transmission lines for high power space systems

NASA Technical Reports Server (NTRS)

Schwarze, G. E.

1985-01-01

As space power levels increase to meet mission objectives and also as the transmission distance between power source and load increases, the mass, volume, power loss, and operating voltage and temperature become important system design considerations. This analysis develops the dependence of the specific mass and percent power loss on hte power and voltage levels, transmission distance, operating temperature and conductor material properties. Only radiation cooling is considered since the transmission line is assumed to operate in a space environment. The results show that the limiting conditions for achieving low specific mass, percent power loss, and volume for a space-type dc transmission line are the permissible transmission voltage and operating temperature. Other means to achieve low specific mass include the judicious choice of conductor materials. The results of this analysis should be immediately applicable to power system trade-off studies including comparisons with ac transmission systems.

Design-Based Research as an Informal Learning Model for Choral Conductors

ERIC Educational Resources Information Center

Cooper, Naomi

2017-01-01

The number of community choirs continues to grow, and literature endorsing the benefits of choral singing for physical, mental and emotional health and well-being is rapidly expanding, meaning that the professional development of community choral conductors is in the public interest. However, research on choral conductor education remains limited.…

Assessment of conductor degradation in the ITER CS insert coil and implications for the ITER conductors

NASA Astrophysics Data System (ADS)

Mitchell, N.

2007-01-01

Nb3Sn cable in conduit-type conductors were expected to provide an efficient way of achieving large conductor currents at high field (up to 13 T) combined with good stability to electromagnetic disturbances due to the extensive helium contact area with the strands. Although ITER model coils successfully reached their design performance (Kato et al 2001 Fusion Eng. Des. 56/57 59-70), initial indications (Mitchell 2003 Fusion Eng. Des. 66-68 971-94) that there were unexplained performance shortfalls have been confirmed. Recent conductor tests (Pasztor et al 2004 IEEE Trans. Appl. Supercond. 14 1527-30) and modelling work (Mitchell 2005 Supercond. Sci. Technol. 18 396-404) suggest that the shortfalls are due to a combination of strand bending and filament fracture under the transverse magnetic loads. Using the new model, the extensive database from the ITER CS insert coil has been reassessed. A parametric fit based on a loss of filament area and n (the exponent of the power-law fit to the electric field) combined with a more rigorous consideration of the conductor field gradient has enabled the coil behaviour to be explained much more consistently than in earlier assessments, now fitting the Nb3Sn strain scaling laws when used with measurements of the conductor operating strain, including conditions when the insert coil current (and hence operating strain) were reversed. The coil superconducting performance also shows a fatigue-type behaviour consistent with recent measurements on conductor samples (Martovetsky et al 2005 IEEE Trans. Appl. Supercond. 15 1367-70). The ITER conductor design has already been modified compared to the CS insert, to increase the margin and provide increased resistance to the degradation, by using a steel jacket to provide thermal pre-compression to reduce tensile strain levels, reducing the void fraction from 36% to 33% and increasing the non-copper material by 25%. Test results are not yet available for the new design and performance predictions at present rely on models with limited verification.

Analytical investigation in bending characteristic of twisted stacked-tape cable conductor

NASA Astrophysics Data System (ADS)

Takayasu, Makoto; Chiesa, Luisa

2015-12-01

An analytical model to evaluate bending strains of a twisted stack-tape cable (TSTC) conductor has been developed. Through a comparison with experimental results obtained for a soldered 32-tape YBCO TSTC conductor, it has been found that a Perfect-Slip Model (PSM) taking into account the slipping between tapes in a stacked-tape cable during bending gives much better estimation of the bending performance compared to a No-Slip Model (NSM). In the PSM case the tapes can slip so that the internal longitudinal axial strain can be released. The longitudinal strains of compression and tension regions along the tape are balanced in one twist-pitch and cancel out evenly in a long cable. Therefore, in a cable the strains due to bending can be minimized. This is an important advantage of a TSTC conductor. The effect of the cable diameter size on the bending strain is also expected to be minor, and all tapes composing a TSTC conductor have the same strain response under bending, therefore the cable critical current can be characterized from a single tape behaviour.

Pulmonary function abnormalities associated with exposure to automobile exhaust in a diesel bus garage and roads.

PubMed

Chattopadhyay, B P; Alam, J; Roychowdhury, A

2003-01-01

In Kolkata city the road transports are maintained by private and Government organization. A major work force belonged to the State Transport Corporation (KSTC), Government of West-Bengal. The pollution caused by these vehicles affects the workers health and caused different types of respiratory problems. This study was undertaken to assess the pulmonary function status of these workers. City KSTC garage workers were investigated and categorically divided into two group: garage mechanics and the (2) those transporting the passengers (drivers and conductors). Vital capacity (VC), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) were recorded by Spirovit-SP-10 (Schiller Ltd, Switzerland) and Wright's Peak Flow Meter (UK) on 236 workers. The different flow volumes, FEV(1), FEV(1%), and flow rates, FEF(02-121), FEF(25-75%), etc. were calculated. The administrative people had higher PFT than the other categories. Drivers and conductors have almost equal mean PFT values but mechanical workers had slightly higher. PFT values according to different age ranges and duration of exposure showed gradual decrement as age and duration of exposure increased. Non-smokers had higher lung volumes compared to smokers and ex-smokers. Restrictive, obstructive and combined types of impairments were noticed in 28.4%, 1.7% and 2.9%, respectively, workers. The restrictive impairment was found to be 30.4% in conductors; 28.9% in drivers, 27.9% in mechanics and 21.7% in administration people. Obstructive type of impairment was found to be 2.9% in both drivers and conductors. The effect of pollution by dust and fumes may be responsible for these pulmonary function impairments, restrictive impairments being greater.

Computer simulation comparison of tripolar, bipolar, and spline Laplacian electrocadiogram estimators.

PubMed

Chen, T; Besio, W; Dai, W

2009-01-01

A comparison of the performance of the tripolar and bipolar concentric as well as spline Laplacian electrocardiograms (LECGs) and body surface Laplacian mappings (BSLMs) for localizing and imaging the cardiac electrical activation has been investigated based on computer simulation. In the simulation a simplified eccentric heart-torso sphere-cylinder homogeneous volume conductor model were developed. Multiple dipoles with different orientations were used to simulate the underlying cardiac electrical activities. Results show that the tripolar concentric ring electrodes produce the most accurate LECG and BSLM estimation among the three estimators with the best performance in spatial resolution.

Discussion of Source Reconstruction Models Using 3D MCG Data

NASA Astrophysics Data System (ADS)

Melis, Massimo De; Uchikawa, Yoshinori

In this study we performed the source reconstruction of magnetocardiographic signals generated by the human heart activity to localize the site of origin of the heart activation. The localizations were performed in a four compartment model of the human volume conductor. The analyses were conducted on normal subjects and on a subject affected by the Wolff-Parkinson-White syndrome. Different models of the source activation were used to evaluate whether a general model of the current source can be applied in the study of the cardiac inverse problem. The data analyses were repeated using normal and vector component data of the MCG. The results show that a distributed source model has the better accuracy in performing the source reconstructions, and that 3D MCG data allow finding smaller differences between the different source models.

Hierarchical Material Properties in Finite Element Analysis: The Oilfield Infrastructure Problem.

NASA Astrophysics Data System (ADS)

Weiss, C. J.; Wilson, G. A.

2017-12-01

Geophysical simulation of low-frequency electromagnetic signals within built environments such as urban centers and industrial landscapes facilities is a challenging computational problem because strong conductors (e.g., pipes, fences, rail lines, rebar, etc.) are not only highly conductive and/or magnetic relative to the surrounding geology, but they are very small in one or more of their physical length coordinates. Realistic modeling of such structures as idealized conductors has long been the standard approach; however this strategy carries with it computational burdens such as cumbersome implementation of internal boundary conditions, and limited flexibility for accommodating realistic geometries. Another standard approach is "brute force" discretization (often coupled with an equivalent medium model) whereby 100's of millions of voxels are used to represent these strong conductors, but at the cost of extreme computation times (and mesh design) for a simulation result when possible. To minimize these burdens, a new finite element scheme (Weiss, Geophysics, 2017) has been developed in which the material properties reside on a hierarchy of geometric simplicies (i.e., edges, facets and volumes) within an unstructured tetrahedral mesh. This allows thin sheet—like structures, such as subsurface fractures, to be economically represented by a connected set of triangular facets, for example, that freely conform to arbitrary "real world" geometries. The same holds thin pipe/wire-like structures, such as casings or pipelines. The hierarchical finite element scheme has been applied to problems in electro- and magnetostatics for oilfield problems where the elevated, but finite, conductivity and permeability of the steel-cased oil wells must be properly accounted for, yielding results that are otherwise unobtainable, with run times as low as a few 10s of seconds. Extension of the hierarchical finite element concept to broadband electromagnetics is presently underway, as are its implications for geophysical inversion.

The role of blood vessels in high-resolution volume conductor head modeling of EEG.

PubMed

Fiederer, L D J; Vorwerk, J; Lucka, F; Dannhauer, M; Yang, S; Dümpelmann, M; Schulze-Bonhage, A; Aertsen, A; Speck, O; Wolters, C H; Ball, T

2016-03-01

Reconstruction of the electrical sources of human EEG activity at high spatio-temporal accuracy is an important aim in neuroscience and neurological diagnostics. Over the last decades, numerous studies have demonstrated that realistic modeling of head anatomy improves the accuracy of source reconstruction of EEG signals. For example, including a cerebro-spinal fluid compartment and the anisotropy of white matter electrical conductivity were both shown to significantly reduce modeling errors. Here, we for the first time quantify the role of detailed reconstructions of the cerebral blood vessels in volume conductor head modeling for EEG. To study the role of the highly arborized cerebral blood vessels, we created a submillimeter head model based on ultra-high-field-strength (7T) structural MRI datasets. Blood vessels (arteries and emissary/intraosseous veins) were segmented using Frangi multi-scale vesselness filtering. The final head model consisted of a geometry-adapted cubic mesh with over 17×10(6) nodes. We solved the forward model using a finite-element-method (FEM) transfer matrix approach, which allowed reducing computation times substantially and quantified the importance of the blood vessel compartment by computing forward and inverse errors resulting from ignoring the blood vessels. Our results show that ignoring emissary veins piercing the skull leads to focal localization errors of approx. 5 to 15mm. Large errors (>2cm) were observed due to the carotid arteries and the dense arterial vasculature in areas such as in the insula or in the medial temporal lobe. Thus, in such predisposed areas, errors caused by neglecting blood vessels can reach similar magnitudes as those previously reported for neglecting white matter anisotropy, the CSF or the dura - structures which are generally considered important components of realistic EEG head models. Our findings thus imply that including a realistic blood vessel compartment in EEG head models will be helpful to improve the accuracy of EEG source analyses particularly when high accuracies in brain areas with dense vasculature are required. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Electrical Potential of Leaping Eels

PubMed Central

Catania, Kenneth C.

2017-01-01

When approached by a large, partially submerged conductor, electric eels (Electrophorus electricus) will often defend themselves by leaping from the water to directly shock the threat. Presumably, the conductor is interpreted as an approaching terrestrial or semiaquatic animal. In the course of this defensive behavior, eels first make direct contact with their lower jaw and then rapidly emerge from the water, ascending the conductor while discharging high-voltage volleys. In this study, the equivalent circuit that develops during this behavior was proposed and investigated. First, the electromotive force and internal resistance of four electric eels were determined. These values were then used to estimate the resistance of the water volume between the eel and the conductor by making direct measurements of current with the eel and water in the circuit. The resistance of the return path from the eel's lower jaw to the main body of water was then determined, based on voltage recordings, for each electric eel at the height of the defensive leap. Finally, the addition of a hypothetical target for the leaping defense was considered as part of the circuit. The results suggest the defensive behavior efficiently directs electrical current through the threat, producing an aversive and deterring experience by activating afferents in potential predators. PMID:28651251

Development of termination and utilization concepts for flat conductor cables. Volume 3: Cost study comparison, flat versus round conductor cable

NASA Technical Reports Server (NTRS)

1972-01-01

A cost study comparing flat conductor cable (FCC) with small-gage wire (SGW) and conventional round conductor cable (RCC) is presented. This study was based on a vehicle wiring system consisting of 110,000 ft of conventional RCC equally divided between AWG sizes 20,22, and 24 using MIL-W-81044-type wire and MIL-C-26500 circular connectors. Basic cost data were developed on a similar-sized commercial jet airplane wiring system on a previous company R&D program in which advanced wiring techniques were carried through equivalent installations on an airplane mockup; and on data developed on typical average bundles during this program. Various cost elements included were engineering labor, operations (manufacturing) labor, material costs, and cost impact on payload. Engineering labor includes design, wiring system integration, wiring diagrams and cable assembly drawings, wire installations, and other related supporting functions such as the electronic data processing for the wiring. Operations labor includes mockup, tooling and production planning, fabrication, assembly, installation, and quality control cost impact on payload is the conversion of wiring system weight variations through use of different wiring concepts to program payload benefits in terms of dollars.

Mobility propagation and dynamic facilitation in superionic conductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Annamareddy, Ajay, E-mail: vkannama@ncsu.edu; Eapen, Jacob, E-mail: jacob.eapen@ncsu.edu

2015-11-21

In an earlier work [V. A. Annamareddy et al., Phys. Rev. E 89, 010301(R) (2014)], we showed the manifestation of dynamical heterogeneity (DH)—the presence of clustered mobile and immobile regions—in UO{sub 2}, a model type II superionic conductor. In the current work, we demonstrate the mechanism of dynamic facilitation (DF) in two superionic conductors (CaF{sub 2} and UO{sub 2}) using atomistic simulations. Using the mobility transfer function, DF is shown to vary non-monotonically with temperature with the intensity of DF peaking at temperatures close to the superionic transition temperature (T{sub λ}). Both the metrics quantifying DH and DF show remarkablemore » correspondence implying that DF, in the framework of kinematically constrained models, underpins the heterogeneous dynamics in type II superionic conductors.« less

Statistical characteristic in time-domain of direct current corona-generated audible noise from conductor in corona cage

NASA Astrophysics Data System (ADS)

Li, Xuebao; Cui, Xiang; Lu, Tiebing; Ma, Wenzuo; Bian, Xingming; Wang, Donglai; Hiziroglu, Huseyin

2016-03-01

The corona-generated audible noise (AN) has become one of decisive factors in the design of high voltage direct current (HVDC) transmission lines. The AN from transmission lines can be attributed to sound pressure pulses which are generated by the multiple corona sources formed on the conductor, i.e., transmission lines. In this paper, a detailed time-domain characteristics of the sound pressure pulses, which are generated by the DC corona discharges formed over the surfaces of a stranded conductors, are investigated systematically in a laboratory settings using a corona cage structure. The amplitude of sound pressure pulse and its time intervals are extracted by observing a direct correlation between corona current pulses and corona-generated sound pressure pulses. Based on the statistical characteristics, a stochastic model is presented for simulating the sound pressure pulses due to DC corona discharges occurring on conductors. The proposed stochastic model is validated by comparing the calculated and measured A-weighted sound pressure level (SPL). The proposed model is then used to analyze the influence of the pulse amplitudes and pulse rate on the SPL. Furthermore, a mathematical relationship is found between the SPL and conductor diameter, electric field, and radial distance.

Aeolian vibration control of overhead electrical transmission line conductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sireteanu, T.; Migdalovici, M.; Videa, E.

The paper presents a mathematical model and an analytical procedure to control the wind induced vibration of a single conductor such that the dynamic strain about the suspension clamp is kept within the imposed safety limits. The method is based on the energy balance principle which takes into account the wind energy input, the energy dissipated by the conductor self-damping properties and by the Stockbridge dampers which are frequently used for the aeolian vibration control. The damping characteristics of the Stockbridge dampers are expressed in terms of their mechanical impedance determined experimentally on a vibration exciter. The method can bemore » used to establish whether or not it is necessary to equip the conductor by Stockbridge dampers, which type of damper is more suitable for a given conductor, span length and EDS (every day stress), the necessary number of dampers as well as their optimum spacing on the conductor.« less

PREFACE: International Symposium on Molecular Conductors: Novel Functions of Molecular Conductors under Extreme Conditions (ISMC 2008)

NASA Astrophysics Data System (ADS)

Takahashi, Toshihiro; Suzumura, Yoshikazu

2008-02-01

The International Symposium on Molecular Conductors 2008 (ISMC2008) was held as the second international symposium of the project entitled `Novel Functions of Molecular Conductors under Extreme Conditions', which was supported by the Grant-in-aid for Scientific Research on Priority Areas from the Ministry of Education, Culture, Sports, Science and Technology in Japan. The project lasted from September 2003 to March 2008, and was completed by this symposium held at Okazaki Conference Center, Institute for Molecular Science, Okazaki, Japan (23-25 July 2008), which about 100 scientists attended. During the symposium, five project teams gave summary talks and exciting talks were given on the topics developed recently not only by the members of the project but also by other scientists including invited speakers from abroad, who are doing active research on molecular conductors. It is expected that papers presented in the symposium will give valuable hints for the next step in the research of this field. Therefore the organizers of this symposium decided to publish this proceedings in order to demonstrate these activities, not only for the local community of the project, but also for the broad society of international scientists who are interested in molecular conductors. The editors, who are also the organizers of this symposium, believe that this proceedings provides a significant and relevant contribution to the field of molecular conductors since it is the first time we have published such a proceedings as an electronic journal. We note that all papers published in this volume of Journal of Physics: Conference Series have been peer reviewed by expert referees. Editors made every effort to satisfy the criterion of a proceedings journal published by IOP Publishing. Toshihiro Takahashi and Yoshikazu Suzumura Editors: Toshihiro Takahashi (Gakushuin University) (Chairman) Kazushi Kanoda (University of Tokyo) Seiichi Kagoshima (University of Tokyo) Takehiko Mori (Tokyo Institute of Technology) Yohji Misaki (Ehime University) Yoshikazu Suzumura (Nagoya University) (Chief editor) Conference photograph

Numerical electromagnetic frequency domain analysis with discrete exterior calculus

NASA Astrophysics Data System (ADS)

Chen, Shu C.; Chew, Weng Cho

2017-12-01

In this paper, we perform a numerical analysis in frequency domain for various electromagnetic problems based on discrete exterior calculus (DEC) with an arbitrary 2-D triangular or 3-D tetrahedral mesh. We formulate the governing equations in terms of DEC for 3-D and 2-D inhomogeneous structures, and also show that the charge continuity relation is naturally satisfied. Then we introduce a general construction for signed dual volume to incorporate material information and take into account the case when circumcenters fall outside triangles or tetrahedrons, which may lead to negative dual volume without Delaunay triangulation. Then we examine the boundary terms induced by the dual mesh and provide a systematical treatment of various boundary conditions, including perfect magnetic conductor (PMC), perfect electric conductor (PEC), Dirichlet, periodic, and absorbing boundary conditions (ABC) within this method. An excellent agreement is achieved through the numerical calculation of several problems, including homogeneous waveguides, microstructured fibers, photonic crystals, scattering by a 2-D PEC, and resonant cavities.

Humidity Effect on Nanoscale Electrochemistry in Solid Silver Ion Conductors and the Dual Nature of Its Locality

DOE PAGES

Yang, Sangmo; Strelcov, Evgheni; Paranthaman, Mariappan Parans; ...

2015-01-07

Scanning probe microscopy (SPM) is a powerful tool to investigate electrochemistry in nanoscale volumes. While most SPM-based studies have focused on reactions at the tip-surface junction, charge and mass conservation requires coupled and intrinsically non-local cathodic and anodic processes that can be significantly affected by ambient humidity. Here, we explore the role of water in both cathodic and anodic processes, associated charge transport, and topographic volume changes depending on the polarity of tip bias. The first-order reversal curve current-voltage technique combined with simultaneous detection of the sample topography, referred to as FORC-IVz, was applied to a silver solid ion conductor.more » We found that the protons generated from water affect silver ionic conduction, silver particle formation and dissolution, and mechanical integrity of the material. This work highlights the dual nature (simultaneously local and non-local) of electrochemical SPM studies, which should be considered for comprehensive understanding of nanoscale electrochemistry.« less

Humidity effect on nanoscale electrochemistry in solid silver ion conductors and the dual nature of its locality.

PubMed

Yang, Sang Mo; Strelcov, Evgheni; Paranthaman, M Parans; Tselev, Alexander; Noh, Tae Won; Kalinin, Sergei V

2015-02-11

Scanning probe microscopy (SPM) is a powerful tool to investigate electrochemistry in nanoscale volumes. While most SPM-based studies have focused on reactions at the tip-surface junction, charge and mass conservation requires coupled and intrinsically nonlocal cathodic and anodic processes that can be significantly affected by ambient humidity. Here, we explore the role of water in both cathodic and anodic processes, associated charge transport, and topographic volume changes depending on the polarity of tip bias. The first-order reversal curve current-voltage technique combined with simultaneous detection of the sample topography, referred to as FORC-IVz, was applied to a silver solid ion conductor. We found that the protons generated from water affect silver ionic conduction, silver particle formation and dissolution, and mechanical integrity of the material. This work highlights the dual nature (simultaneously local and nonlocal) of electrochemical SPM studies, which should be considered for comprehensive understanding of nanoscale electrochemistry.

A novel eddy current damper: theory and experiment

NASA Astrophysics Data System (ADS)

Ebrahimi, Babak; Khamesee, Mir Behrad; Golnaraghi, Farid

2009-04-01

A novel eddy current damper is developed and its damping characteristics are studied analytically and experimentally. The proposed eddy current damper consists of a conductor as an outer tube, and an array of axially magnetized ring-shaped permanent magnets separated by iron pole pieces as a mover. The relative movement of the magnets and the conductor causes the conductor to undergo motional eddy currents. Since the eddy currents produce a repulsive force that is proportional to the velocity of the conductor, the moving magnet and the conductor behave as a viscous damper. The eddy current generation causes the vibration to dissipate through the Joule heating generated in the conductor part. An accurate, analytical model of the system is obtained by applying electromagnetic theory to estimate the damping properties of the proposed eddy current damper. A prototype eddy current damper is fabricated, and experiments are carried out to verify the accuracy of the theoretical model. The experimental test bed consists of a one-degree-of-freedom vibration isolation system and is used for the frequency and transient time response analysis of the system. The eddy current damper model has a 0.1 m s-2 (4.8%) RMS error in the estimation of the mass acceleration. A damping coefficient as high as 53 Ns m-1 is achievable with the fabricated prototype. This novel eddy current damper is an oil-free, inexpensive damper that is applicable in various vibration isolation systems such as precision machinery, micro-mechanical suspension systems and structure vibration isolation.

Model construction and superconductivity analysis of organic conductors β-(BDA-TTP)2MF6 (M = P, As, Sb and Ta) based on first-principles band calculation

NASA Astrophysics Data System (ADS)

Aizawa, H.; Kuroki, K.; Yasuzuka, S.; Yamada, J.

2012-11-01

We perform a first-principles band calculation for a group of quasi-two-dimensional organic conductors β-(BDA-TTP)2MF6 (M = P, As, Sb and Ta). The ab-initio calculation shows that the density of states is correlated with the bandwidth of the singly occupied (highest) molecular orbital, while it is not necessarily correlated with the unit-cell volume. The direction of the major axis of the cross section of the Fermi surface lies in the Γ-B-direction, which differs from that obtained by the extended Hückel calculation. Then, we construct a tight-binding model which accurately reproduces the ab-initio band structure. The obtained transfer energies give a smaller dimerization than in the extended Hückel band. As to the difference in the anisotropy of the Fermi surface, the transfer energies along the inter-stacking direction are smaller than those obtained in the extended Hückel calculation. Assuming spin-fluctuation-mediated superconductivity, we apply random phase approximation to a two-band Hubbard model. This two-band Hubbard model is composed of the tight-binding model derived from the first-principles band structure and an on-site (intra-molecule) repulsive interaction taken as a variable parameter. The obtained superconducting gap changes sign four times along the Fermi surface like in a d-wave gap, and the nodal direction is different from that obtained in the extended Hückel model. Anion dependence of Tc is qualitatively consistent with the experimental observation.

A simple node and conductor data generator for SINDA

NASA Technical Reports Server (NTRS)

Gottula, Ronald R.

1992-01-01

This paper presents a simple, automated method to generate NODE and CONDUCTOR DATA for thermal match modes. The method uses personal computer spreadsheets to create SINDA inputs. It was developed in order to make SINDA modeling less time consuming and serves as an alternative to graphical methods. Anyone having some experience using a personal computer can easily implement this process. The user develops spreadsheets to automatically calculate capacitances and conductances based on material properties and dimensional data. The necessary node and conductor information is then taken from the spreadsheets and automatically arranged into the proper format, ready for insertion directly into the SINDA model. This technique provides a number of benefits to the SINDA user such as a reduction in the number of hand calculations, and an ability to very quickly generate a parametric set of NODE and CONDUCTOR DATA blocks. It also provides advantages over graphical thermal modeling systems by retaining the analyst's complete visibility into the thermal network, and by permitting user comments anywhere within the DATA blocks.

Magnetic flux-load current interactions in ferrous conductors

NASA Astrophysics Data System (ADS)

Cannell, Michael J.; McConnell, Richard A.

1992-06-01

A modeling technique has been developed to account for interactions between load current and magnetic flux in an iron conductor. Such a conductor would be used in the active region of a normally conducting homopolar machine. This approach has been experimentally verified and its application to a real machine demonstrated. Additionally, measurements of the resistivity of steel under the combined effects of magnetic field and current have been conducted.

Fiber optic quench detection via optimized Rayleigh Scattering in high-field YBCO accelerator magnets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flanagan, Gene

Yttrium barium copper oxide (YBCO) coated conductors are known for their ability to operate in the superconducting state at relatively high temperatures, even above the boiling point of liquid nitrogen (77 K). When these same conductors are operated at lower temperatures, they are able to operate in much higher magnetic fields than traditional superconductors like NiTi or Nb 3Sn. Thus, YBCO superconducting magnets are one of the primary options for generating the high magnetic fields needed for future high energy physics devices. Due to slow quench propagation, quench detection remains one of the primary limitations to YBCO magnets. Fiber opticmore » sensing, based upon Rayleigh scattering, has the potential for spatial resolution approaching the wavelength of light, or very fast temporal resolution at low spatial resolution, and a continuum of combinations in between. This project has studied, theoretically and experimentally, YBCO magnets and Rayleigh scattering quench detection systems to demonstrate feasibility of the systems for YBCO quench protection systems. Under this grant an experimentally validated 3D quench propagation model was used to accurately define the acceptable range of spatial and temporal resolutions for effective quench detection in YBCO magnets and to evaluate present-day and potentially improved YBCO conductors. The data volume and speed requirements for quench detection via Rayleigh scattering required the development of a high performance fiber optic based quench detection/data acquisition system and its integration with an existing voltage tap/thermo-couple based system. In this project, optical fibers are tightly co-wound into YBCO magnet coils, with the fiber on top of the conductor as turn-to-turn insulation. Local changes in the temperature or strain of the conductor are sensed by the optical fiber, which is in close thermal and mechanical contact with the conductor. Intrinsic imperfections in the fiber reflect Rayleigh backscattered laser signals that are shifted by the changes in the fiber that are induced by a local change in the YBCO temperature or strain. One goal of this project was to show that modern technology can be used to interrogate the signals from a (very expensive) YBCO magnet to detect an impending quench in time to protect it from self-destruction. The results show that Rayleigh-backscattering interrogated optical fibers (RIOF) have significant advantages over traditional techniques, including very high spatial resolution and the ability to detect a hot-spot well before the peak local temperature becomes so high that the conductor can be damaged. RIOF quench detection is intrinsically faster than voltage taps, and this intrinsic advantage is greater as the coil size and/or current margin increases. We describe the development and testing program performed under the grant.« less

A discrete method for modal analysis of overhead line conductor bundles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Migdalovici, M.A.; Sireteanu, T.D.; Albrecht, A.A.

The paper presents a mathematical model and a semi-analytical procedure to calculate the vibration modes and eigenfrequencies of single or bundled conductors with spacers which are needed for evaluation of the wind induced vibration of conductors and for optimization of spacer-dampers placement. The method consists in decomposition of conductors in modules and the expansion by polynomial series of unknown displacements on each module. A complete system of polynomials are deduced for this by Legendre polynomials. Each module is considered either boundary conditions at the extremity of the module or the continuity conditions between the modules and also a number ofmore » projections of module equilibrium equation on the polynomials from the expansion series of unknown displacement. The global system of the eigenmodes and eigenfrequencies is of the matrix form: A X + {omega}{sup 2} M X = 0. The theoretical considerations are exemplified on one conductor and on bundle of two conductors with spacers. From this, a method for forced vibration calculus of a single or bundled conductors is also presented.« less

Flux-pinning-induced interfacial shearing and transverse normal stress in a superconducting coated conductor long strip

NASA Astrophysics Data System (ADS)

Jing, Ze; Yong, Huadong; Zhou, Youhe

2012-08-01

In this paper, a theoretical model is proposed to analyze the transverse normal stress and interfacial shearing stress induced by the electromagnetic force in the superconducting coated conductor. The plane strain approach is used and a singular integral equation is derived. By assuming that the critical current density is magnetic field independent and the superconducting film is infinitely thin, the interfacial shearing stress and normal stress in the film are evaluated for the coated conductor during the increasing and decreasing in the transport current, respectively. The calculation results are discussed and compared for the conductor with different substrate and geometry. The results indicate that the coated conductor with stiffer substrate and larger width experiences larger interfacial shearing stress and less normal stress in the film.

Room Temperature Ammonia Gas Sensing Using Mixed Conductor based TEMPOS Structures.

PubMed

Saroch, Mamta; Srivastava, Sunita; Fink, Dietmar; Chandra, Amita

2008-10-14

The current/voltage characteristics of mixed (ion+electron) conductor-based 'TEMPOS' (Tunable Electronic Material with Pores in Oxide on Silicon) structures are reported. TEMPOS are novel electronic MOS-like structures having etched swift heavy ion tracks (i.e., nanopores) in the dielectric layer filled with some conducting material. The three contacts (two on top and one on the bottom), which resemble the classical bipolar or field effect transistor arrangements are, in principle, interchangeable when the overall electrical resistance along the tracks and on the surface are similar. Consequently, three configurations are obtained by interchanging the top contacts with the base contact in electronic circuits. The current/voltage characteristics show a diode like behaviour. Impedance measurements have been made for TEMPOS structures with tracks filled with ion conductors and also mixed conductors to study the ammonia sensing behaviour. The impedance has been found to be a function of frequency and magnitude of the applied signal and concentration of the ammonia solution. This is attributed to the large number of charge carriers (here protons) available for conduction on exposure to ammonia and also to the large surface to volume ratio of the polymer composites embedded in the ion tracks. The measurement of both, the real and imaginary parts of impedance allows one to enhance the detection sensitivity greatly.

Electrical Potential of Leaping Eels.

PubMed

Catania, Kenneth C

2017-01-01

When approached by a large, partially submerged conductor, electric eels (Electrophorus electricus) will often defend themselves by leaping from the water to directly shock the threat. Presumably, the conductor is interpreted as an approaching terrestrial or semiaquatic animal. In the course of this defensive behavior, eels first make direct contact with their lower jaw and then rapidly emerge from the water, ascending the conductor while discharging high-voltage volleys. In this study, the equivalent circuit that develops during this behavior was proposed and investigated. First, the electromotive force and internal resistance of four electric eels were determined. These values were then used to estimate the resistance of the water volume between the eel and the conductor by making direct measurements of current with the eel and water in the circuit. The resistance of the return path from the eel's lower jaw to the main body of water was then determined, based on voltage recordings, for each electric eel at the height of the defensive leap. Finally, the addition of a hypothetical target for the leaping defense was considered as part of the circuit. The results suggest the defensive behavior efficiently directs electrical current through the threat, producing an aversive and deterring experience by activating afferents in potential predators. © 2017 The Author(s) Published by S. Karger AG, Basel.

Room Temperature Ammonia Gas Sensing Using Mixed Conductor based TEMPOS Structures

PubMed Central

Saroch, Mamta; Srivastava, Sunita; Fink, Dietmar; Chandra, Amita

2008-01-01

The current/voltage characteristics of mixed (ion+electron) conductor-based ‘TEMPOS’ (Tunable Electronic Material with Pores in Oxide on Silicon) structures̵ are reported. TEMPOS are novel electronic MOS-like structures having etched swift heavy ion tracks (i.e., nanopores) in the dielectric layer filled with some conducting material. The three contacts (two on top and one on the bottom), which resemble the classical bipolar or field effect transistor arrangements are, in principle, interchangeable when the overall electrical resistance along the tracks and on the surface are similar. Consequently, three configurations are obtained by interchanging the top contacts with the base contact in electronic circuits. The current/voltage characteristics show a diode like behaviour. Impedance measurements have been made for TEMPOS structures with tracks filled with ion conductors and also mixed conductors to study the ammonia sensing behaviour. The impedance has been found to be a function of frequency and magnitude of the applied signal and concentration of the ammonia solution. This is attributed to the large number of charge carriers (here protons) available for conduction on exposure to ammonia and also to the large surface to volume ratio of the polymer composites embedded in the ion tracks. The measurement of both, the real and imaginary parts of impedance allows one to enhance the detection sensitivity greatly. PMID:27873874

Statistical characteristic in time-domain of direct current corona-generated audible noise from conductor in corona cage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Xuebao, E-mail: lxb08357x@ncepu.edu.cn; Cui, Xiang, E-mail: x.cui@ncepu.edu.cn; Ma, Wenzuo

The corona-generated audible noise (AN) has become one of decisive factors in the design of high voltage direct current (HVDC) transmission lines. The AN from transmission lines can be attributed to sound pressure pulses which are generated by the multiple corona sources formed on the conductor, i.e., transmission lines. In this paper, a detailed time-domain characteristics of the sound pressure pulses, which are generated by the DC corona discharges formed over the surfaces of a stranded conductors, are investigated systematically in a laboratory settings using a corona cage structure. The amplitude of sound pressure pulse and its time intervals aremore » extracted by observing a direct correlation between corona current pulses and corona-generated sound pressure pulses. Based on the statistical characteristics, a stochastic model is presented for simulating the sound pressure pulses due to DC corona discharges occurring on conductors. The proposed stochastic model is validated by comparing the calculated and measured A-weighted sound pressure level (SPL). The proposed model is then used to analyze the influence of the pulse amplitudes and pulse rate on the SPL. Furthermore, a mathematical relationship is found between the SPL and conductor diameter, electric field, and radial distance.« less

Development of an electrical model for integrated magnetic inductors

NASA Astrophysics Data System (ADS)

Bechir, M. B.; Yaya, D. D.; Youssouf, M. K.; Soultan, M.; Capraro, S.; Siblini, A.; Chatelon, J. P.; Rousseau, J. J.

2014-07-01

Nowadays, the current trend consists in the development of new technologies with the aim of reducing volume, weight as well as production cost. With the aim of decreasing occupied component area, it will be interesting to use magnetic materials to confine the fields. Therefore, our works concern the modelling and the characterization of magnetic planar inductors. The proposed model is detailed for inductors fabricated with one magnetic layer. The model can take into account, the capacitance between turns and the capacitance between the last turn and the ground plane, the magnetic permeability, the skin and proximity effects of the conductors according to the frequency. The structure of optimization developed to extract the parameters of the model will be presented. Results of extracted parameters are compared with the simulation parameters. A good correlation is observed on Y11 and Y12 parameters on all the broad band frequency.

Canonical Statistical Model for Maximum Expected Immission of Wire Conductor in an Aperture Enclosure

NASA Technical Reports Server (NTRS)

Bremner, Paul G.; Vazquez, Gabriel; Christiano, Daniel J.; Trout, Dawn H.

2016-01-01

Prediction of the maximum expected electromagnetic pick-up of conductors inside a realistic shielding enclosure is an important canonical problem for system-level EMC design of space craft, launch vehicles, aircraft and automobiles. This paper introduces a simple statistical power balance model for prediction of the maximum expected current in a wire conductor inside an aperture enclosure. It calculates both the statistical mean and variance of the immission from the physical design parameters of the problem. Familiar probability density functions can then be used to predict the maximum expected immission for deign purposes. The statistical power balance model requires minimal EMC design information and solves orders of magnitude faster than existing numerical models, making it ultimately viable for scaled-up, full system-level modeling. Both experimental test results and full wave simulation results are used to validate the foundational model.

Isothermal and hygrothermal agings of hybrid glass fiber/carbon fiber composite

NASA Astrophysics Data System (ADS)

Barjasteh, Ehsan

New applications of fiber-reinforced polymer composites (FRPCs) are arising in non-traditional sectors of industry, such as civil infrastructure, automotive, and power distribution. For example, composites are being used in place of steel to support high-voltage overhead conductors. In this application, conductive strands of aluminum are wrapped around a solid composite rod comprised of unidirectional carbon and glass fibers in an epoxy matrix, which is commercially called ACCC conductor. Composite-core conductors such as these are expected to eventually replace conventional steel-reinforced conductors because of the reduced sag at high temperatures, lower weight, higher ampacity, and reduced line losses. Despite the considerable advantages in mechanical performance, long-term durability of composite conductors is a major concern, as overhead conductors are expected to retain properties (with minimal maintenance) over a service life that spans multiple decades. These concerns stem from the uncertain effects of long-term environmental exposure, which includes temperature, moisture, radiation, and aggressive chemicals, all of which can be exacerbated by cyclic loads. In general, the mechanical and physical properties of polymer composites are adversely affected by such environmental factors. Consequently, the ability to forecast changes in material properties as a function of environmental exposure, particularly bulk mechanical properties, which are affected by the integrity of fiber-matrix interfaces, is required to design for extended service lives. Polymer composites are susceptible to oxidative degradation at high temperatures approaching but not quite reaching the glass transition temperature ( Tg). Although the fibers are stable at such temperatures, the matrix and especially the fiber-matrix interface can undergo degradation that affects the physical and mechanical properties of the structure over time. Therefore, as a first step, the thermal aging of an anhydride/epoxy network used in composite-reinforced conductor cables was investigated to determine the extent of thermal oxidative (surface effect) and non-oxidative (bulk effect) degradation. Thermal oxidation tests were performed in air-circulating and vacuum ovens at 180°C and 200ºC (the maximum emergency temperature for ACCC conductors). The extent of oxidation during aging was determined by monitoring the thickness of the oxidized layer. Results showed that the oxidized layer thickness did not increase monotonically as a function of exposure time, and even decreased for a limited period of time. A phenomenological reaction-diffusion model was implemented to predict the thickness of oxidized layer, and the calculated results were compared with measurements for aging times up to 10,000 hours. The accuracy of the reaction-diffusion-based thickness values for the isothermally aged epoxy specimen was affected by the permeability properties of the oxidized material, and to a lesser extent by the degree of oxidation. The diffusivity varied because of changes in the density of the oxidized layer, the macro-void content, crack formation, and the molecular structures. To investigate the effects on diffusivity, the morphology of the oxidized layer and the void content was monitored over time. In addition, the density of the oxidized specimens was calculated by direct measurements of volume and weight during exposure. An empirically based volume-loss model was developed to predict the changes in volume of the specimen as a function of aging times and hence to predict the effects on the oxidized layer thickness. Volume-loss measurements provide an indication of material degradation by demonstrating a direct measurement of shrinkage rates and insight into crack initiation, as opposed to typical weight-loss measurements that provide no insight into material failure. Thermal oxidation of a unidirectional carbon-fiber/glass-fiber hybrid composite was also investigated in this study. The aim was to determine oxidation kinetics, degradation mechanisms, oxidation thickness growth (a damage indicator), and oxidation effects on mechanical property. The epoxy composite rods were comprised of a carbon-fiber core and a glass-fiber shell. The thickness of the oxidized layer (TOL) was measured experimentally for samples exposed to 180ºC and 200ºC for up to 8,736 hours. A reaction-diffusion model was developed for each of the two hybrid sections to obtain the oxygen-concentration profile and the TOL within the composite rods. The TOL values measured experimentally were similar to the modeling predictions. The glass-fiber shell functioned as a protective layer, limiting the oxidation of the carbon-fiber core. The domain validity for the reaction-diffusion model was determined from gravimetric experiments by measuring the weight-loss of hybrid composite samples exposed isothermally in air and in vacuum at 200°C for up to 13,104 hours (1.5 years). The results showed that after prolonged thermal exposure, the degradation mechanism changed from thermal oxidation to thermal degradation. Thermogravimetric analysis (TGA) was performed to determine the thermal degradation and stability of the aged composite. The results indicated that the onset temperature of matrix degradation increased by increasing exposure time. Inorganic fillers are widely used in pultruded parts to facilitate pultrusion, especially for long production runs. Therefore, another scope of this study was to investigate the effects of filler on oxidation kinetics and degradation mechanisms during thermal aging of prultruded composite rods. Similar aging tests and oxidation modeling to those for the unfilled composites were performed. The predicted and measured TOL values for filled composites were slightly less than those for unfilled composites. The addition of kaolin fillers did not affect the oxidation mechanism or the reaction rate of the epoxy matrix, although it did cause a slight decrease in the oxygen-transport properties (diffusivity and solubility of oxygen). The effect of thermal aging on mechanical properties of the aged composites was investigated. A relationship was derived relating TOL to tensile strength of the hybrid composite. The tensile strength remained essentially unchanged by thermal oxidation after 52 weeks of exposure. On the contrary, the oxidation resulted in a decrease in short-beam-shear (SBS) strength (a matrix-dominated property) due to degradation of matrix and fiber/matrix interface strength. However, the filled composites showed a lower reduction in SBS strength than that of the unfilled one for an identical duration of exposure. In addition, the effect of thermal aging on glass transition temperature (T g) was determined for isothermal exposures at 180ºC and 200ºC. The simultaneous effects of post-curing and thermal degradation resulted in the change in Tg during exposure. Another study on the composite rod was performed to investigate the sorption kinetics and the effects of moisture on mechanical and physical properties. Sorption curves were obtained for both hybrid and non-hybrid composite rods to determine characteristic parameters, including the diffusion coefficient (D) and the maximum moisture uptake (Minfinity ). The moisture uptake for the hybrid composites generally exhibited Fickian behavior (no hybridization effects), behaving much like non-hybrid composites. A two-dimensional diffusion model was employed to calculate moisture diffusivities in the longitudinal direction. Interfaces and thermally-induced residual stresses affected the moisture diffusion. In addition, the effect of hygrothermal aging on glass transition temperature (Tg), short beam shear strength (SBS), and tensile strength was determined for hygrothermal exposure at 60°C and 85% relative humidity (RH). Property retention and reversibility of property degradation was also measured. Microscopic inspection revealed no evidence of damage. Prediction of the lifetime of carbon-fiber/fiberglass (GF/CF) hybrid composites under various loads and service life conditions requires fundamental knowledge about the degradation mechanisms associated with overhead conductors with the hybrid GF/CF composite cores. This study provides adequate information on mechanical and thermal behaviors of the composite core under prolong isothermal and hygrothermal exposure, which is necessary for defining a lifetime model.

The European Alps as an interrupter of the Earth's conductivity structures

NASA Astrophysics Data System (ADS)

Al-Halbouni, D.

2013-07-01

Joint interpretation of magnetotelluric and geomagnetic depth sounding results in the period range of 10-105 s in the Western European Alps offer new insights into the conductivity structure of the Earth's crust and mantle. This first large scale electromagnetic study in the Alps covers a cross-section from Germany to northern Italy and shows the importance of the alpine mountain chain as an interrupter of continuous conductors. Poor data quality due to the highly crystalline underground is overcome by Remote Reference and Robust Processing techniques and the combination of both electromagnetic methods. 3-D forward modeling reveals on the one hand interrupted dipping crustal conductors with maximum conductances of 4960 S and on the other hand a lithosphere thickening up to 208 km beneath the central Western Alps. Graphite networks arising from Palaeozoic sedimentary deposits are considered to be accountable for the occurrence of high conductivity and the distribution pattern of crustal conductors. The influence of huge sedimentary Molasse basins on the electromagnetic data is suggested to be minor compared with the influence of crustal conductors. Dipping direction (S-SE) and maximum angle (10.1°) of the northern crustal conductor reveal the main thrusting conditions beneath the Helvetic Alps whereas the existence of a crustal conductor in the Briançonnais supports theses about its belonging to the Iberian Peninsula. In conclusion the proposed model arisen from combined 3-D modeling of noise corrected electromagnetic data is able to explain the geophysical influence of various structural features in and around the Western European Alps and serves as a background for further upcoming studies.

Coherency strain and its effect on ionic conductivity and diffusion in solid electrolytes--an improved model for nanocrystalline thin films and a review of experimental data.

PubMed

Korte, C; Keppner, J; Peters, A; Schichtel, N; Aydin, H; Janek, J

2014-11-28

A phenomenological and analytical model for the influence of strain effects on atomic transport in columnar thin films is presented. A model system consisting of two types of crystalline thin films with coherent interfaces is assumed. Biaxial mechanical strain ε0 is caused by lattice misfit of the two phases. The conjoined films consist of columnar crystallites with a small diameter l. Strain relaxation by local elastic deformation, parallel to the hetero-interface, is possible along the columnar grain boundaries. The spatial extent δ0 of the strained hetero-interface regions can be calculated, assuming an exponential decay of the deformation-forces. The effect of the strain field on the local ionic transport in a thin film is then calculated by using the thermodynamic relation between (isostatic) pressure and free activation enthalpy ΔG(#). An expression describing the total ionic transport relative to bulk transport of a thin film or a multilayer as a function of the layer thickness is obtained as an integral average over strained and unstrained regions. The expression depends only on known material constants such as Young modulus Y, Poisson ratio ν and activation volume ΔV(#), which can be combined as dimensionless parameters. The model is successfully used to describe own experimental data from conductivity and diffusion studies. In the second part of the paper a comprehensive literature overview of experimental studies on (fast) ion transport in thin films and multilayers along solid-solid hetero-interfaces is presented. By comparing and reviewing the data the observed interface effects can be classified into three groups: (i) transport along interfaces between extrinsic ionic conductors (and insulator), (ii) transport along an open surface of an extrinsic ionic conductor and (iii) transport along interfaces between intrinsic ionic conductors. The observed effects in these groups differ by about five orders of magnitude in a very consistent way. The modified interface transport in group (i) is most probably caused by strain effects, misfit dislocations or disordered transition regions.

Computing volume potentials for noninvasive imaging of cardiac excitation.

PubMed

van der Graaf, A W Maurits; Bhagirath, Pranav; van Driel, Vincent J H M; Ramanna, Hemanth; de Hooge, Jacques; de Groot, Natasja M S; Götte, Marco J W

2015-03-01

In noninvasive imaging of cardiac excitation, the use of body surface potentials (BSP) rather than body volume potentials (BVP) has been favored due to enhanced computational efficiency and reduced modeling effort. Nowadays, increased computational power and the availability of open source software enable the calculation of BVP for clinical purposes. In order to illustrate the possible advantages of this approach, the explanatory power of BVP is investigated using a rectangular tank filled with an electrolytic conductor and a patient specific three dimensional model. MRI images of the tank and of a patient were obtained in three orthogonal directions using a turbo spin echo MRI sequence. MRI images were segmented in three dimensional using custom written software. Gmsh software was used for mesh generation. BVP were computed using a transfer matrix and FEniCS software. The solution for 240,000 nodes, corresponding to a resolution of 5 mm throughout the thorax volume, was computed in 3 minutes. The tank experiment revealed that an increased electrode surface renders the position of the 4 V equipotential plane insensitive to mesh cell size and reduces simulated deviations. In the patient-specific model, the impact of assigning a different conductivity to lung tissue on the distribution of volume potentials could be visualized. Generation of high quality volume meshes and computation of BVP with a resolution of 5 mm is feasible using generally available software and hardware. Estimation of BVP may lead to an improved understanding of the genesis of BSP and sources of local inaccuracies. © 2014 Wiley Periodicals, Inc.

The New York Head—A precise standardized volume conductor model for EEG source localization and tES targeting

PubMed Central

Huang, Yu; Parra, Lucas C.; Haufe, Stefan

2018-01-01

In source localization of electroencephalograpic (EEG) signals, as well as in targeted transcranial electric current stimulation (tES), a volume conductor model is required to describe the flow of electric currents in the head. Boundary element models (BEM) can be readily computed to represent major tissue compartments, but cannot encode detailed anatomical information within compartments. Finite element models (FEM) can capture more tissue types and intricate anatomical structures, but with the higher precision also comes the need for semiautomated segmentation, and a higher computational cost. In either case, adjusting to the individual human anatomy requires costly magnetic resonance imaging (MRI), and thus head modeling is often based on the anatomy of an ‘arbitrary’ individual (e.g. Colin27). Additionally, existing reference models for the human head often do not include the cerebrospinal fluid (CSF), and their field of view excludes portions of the head and neck—two factors that demonstrably affect current-flow patterns. Here we present a highly detailed FEM, which we call ICBM-NY, or “New York Head”. It is based on the ICBM152 anatomical template (a non-linear average of the MRI of 152 adult human brains) defined in MNI coordinates, for which we extended the field of view to the neck and performed a detailed segmentation of six tissue types (scalp, skull, CSF, gray matter, white matter, air cavities) at 0.5 mm 3 resolution. The model was solved for 231 electrode locations. To evaluate its performance, additional FEMs and BEMs were constructed for four individual subjects. Each of the four individual FEMs (regarded as the ‘ground truth’) is compared to its BEM counterpart, the ICBM-NY, a BEM of the ICBM anatomy, an ‘individualized’ BEM of the ICBM anatomy warped to the individual head surface, and FEMs of the other individuals. Performance is measured in terms of EEG source localization and tES targeting errors. Results show that the ICBM-NY outperforms FEMs of mismatched individual anatomies as well as the BEM of the ICBM anatomy according to both criteria. We therefore propose the New York Head as a new standard head model to be used in future EEG and tES studies whenever an individual MRI is not available. We release all model data online at neuralengr.com/nyhead/ to facilitate broad adoption. PMID:26706450

The New York Head-A precise standardized volume conductor model for EEG source localization and tES targeting.

PubMed

Huang, Yu; Parra, Lucas C; Haufe, Stefan

2016-10-15

In source localization of electroencephalograpic (EEG) signals, as well as in targeted transcranial electric current stimulation (tES), a volume conductor model is required to describe the flow of electric currents in the head. Boundary element models (BEM) can be readily computed to represent major tissue compartments, but cannot encode detailed anatomical information within compartments. Finite element models (FEM) can capture more tissue types and intricate anatomical structures, but with the higher precision also comes the need for semi-automated segmentation, and a higher computational cost. In either case, adjusting to the individual human anatomy requires costly magnetic resonance imaging (MRI), and thus head modeling is often based on the anatomy of an 'arbitrary' individual (e.g. Colin27). Additionally, existing reference models for the human head often do not include the cerebro-spinal fluid (CSF), and their field of view excludes portions of the head and neck-two factors that demonstrably affect current-flow patterns. Here we present a highly detailed FEM, which we call ICBM-NY, or "New York Head". It is based on the ICBM152 anatomical template (a non-linear average of the MRI of 152 adult human brains) defined in MNI coordinates, for which we extended the field of view to the neck and performed a detailed segmentation of six tissue types (scalp, skull, CSF, gray matter, white matter, air cavities) at 0.5mm(3) resolution. The model was solved for 231 electrode locations. To evaluate its performance, additional FEMs and BEMs were constructed for four individual subjects. Each of the four individual FEMs (regarded as the 'ground truth') is compared to its BEM counterpart, the ICBM-NY, a BEM of the ICBM anatomy, an 'individualized' BEM of the ICBM anatomy warped to the individual head surface, and FEMs of the other individuals. Performance is measured in terms of EEG source localization and tES targeting errors. Results show that the ICBM-NY outperforms FEMs of mismatched individual anatomies as well as the BEM of the ICBM anatomy according to both criteria. We therefore propose the New York Head as a new standard head model to be used in future EEG and tES studies whenever an individual MRI is not available. We release all model data online at neuralengr.com/nyhead/ to facilitate broad adoption. Published by Elsevier Inc.

Microstructure of a base metal thick film system. [Glass frit with base metal oxide addition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mentley, D.E.

1976-06-01

A base metal thick film conductor system using glass frits with base metal oxide additions was investigated as metallization for hybrid microcircuits. Application of previous work on wetting and chemical bonding was made to this system. The observation of changes in the properties of the thick film was made by photomicrographs of screened samples and sheet resistivity measurements. In addition to the chemical and wetting properties, the effect of glass frit particle size on conductivity was also analyzed. The base metal oxide addition was found to produce a more consistent thick film conductor at low volume percentages of metal bymore » inhibiting the formation of low melting redox reaction products.« less

Modeling deep brain stimulation: point source approximation versus realistic representation of the electrode

NASA Astrophysics Data System (ADS)

Zhang, Tianhe C.; Grill, Warren M.

2010-12-01

Deep brain stimulation (DBS) has emerged as an effective treatment for movement disorders; however, the fundamental mechanisms by which DBS works are not well understood. Computational models of DBS can provide insights into these fundamental mechanisms and typically require two steps: calculation of the electrical potentials generated by DBS and, subsequently, determination of the effects of the extracellular potentials on neurons. The objective of this study was to assess the validity of using a point source electrode to approximate the DBS electrode when calculating the thresholds and spatial distribution of activation of a surrounding population of model neurons in response to monopolar DBS. Extracellular potentials in a homogenous isotropic volume conductor were calculated using either a point current source or a geometrically accurate finite element model of the Medtronic DBS 3389 lead. These extracellular potentials were coupled to populations of model axons, and thresholds and spatial distributions were determined for different electrode geometries and axon orientations. Median threshold differences between DBS and point source electrodes for individual axons varied between -20.5% and 9.5% across all orientations, monopolar polarities and electrode geometries utilizing the DBS 3389 electrode. Differences in the percentage of axons activated at a given amplitude by the point source electrode and the DBS electrode were between -9.0% and 12.6% across all monopolar configurations tested. The differences in activation between the DBS and point source electrodes occurred primarily in regions close to conductor-insulator interfaces and around the insulating tip of the DBS electrode. The robustness of the point source approximation in modeling several special cases—tissue anisotropy, a long active electrode and bipolar stimulation—was also examined. Under the conditions considered, the point source was shown to be a valid approximation for predicting excitation of populations of neurons in response to DBS.

Reduction in bearing size due to superconductors in magnetic bearings

NASA Technical Reports Server (NTRS)

Rao, Dantam K.; Lewis, Paul; Dill, James F.

1991-01-01

A design concept that reduces the size of magnetic bearings is assessed. The small size will enable magnetic bearings to fit into limited available bearing volume of cryogenic machinery. The design concept, called SUPERC, uses (high Tc) superconductors or high-purity aluminum conductors in windings instead of copper. The relatively high-current density of these conductors reduces the slot radial thickness for windings, which reduces the size of the bearings. MTI developed a sizing program called SUPERC that translates the high-current density of these conductors into smaller sized bearings. This program was used to size a superconducting bearing to carry a 500 lb. load. The sizes of magnetic bearings needed by various design concepts are as follows: SUPERC design concept = 3.75 in.; magnet-bias design concept = 5.25 in.; and all electromagnet design concept = 7.0 in. These results indicate that the SUPERC design concept can significantly reduce the size of the bearing. This reduction, in turn, reduces the weight and yields a lighter bearing. Since the superconductors have inherently near-zero resistance, they are also expected to save power needed for operation considerably.

Apparatus for improving performance of electrical insulating structures

DOEpatents

Wilson, Michael J.; Goerz, David A.

2004-08-31

Removing the electrical field from the internal volume of high-voltage structures; e.g., bushings, connectors, capacitors, and cables. The electrical field is removed from inherently weak regions of the interconnect, such as between the center conductor and the solid dielectric, and places it in the primary insulation. This is accomplished by providing a conductive surface on the inside surface of the principal solid dielectric insulator surrounding the center conductor and connects the center conductor to this conductive surface. The advantage of removing the electric fields from the weaker dielectric region to a stronger area improves reliability, increases component life and operating levels, reduces noise and losses, and allows for a smaller compact design. This electric field control approach is currently possible on many existing products at a modest cost. Several techniques are available to provide the level of electric field control needed. Choosing the optimum technique depends on material, size, and surface accessibility. The simplest deposition method uses a standard electroless plating technique, but other metalization techniques include vapor and energetic deposition, plasma spraying, conductive painting, and other controlled coating methods.

Apparatus for improving performance of electrical insulating structures

DOEpatents

Wilson, Michael J.; Goerz, David A.

2002-01-01

Removing the electrical field from the internal volume of high-voltage structures; e.g., bushings, connectors, capacitors, and cables. The electrical field is removed from inherently weak regions of the interconnect, such as between the center conductor and the solid dielectric, and places it in the primary insulation. This is accomplished by providing a conductive surface on the inside surface of the principal solid dielectric insulator surrounding the center conductor and connects the center conductor to this conductive surface. The advantage of removing the electric fields from the weaker dielectric region to a stronger area improves reliability, increases component life and operating levels, reduces noise and losses, and allows for a smaller compact design. This electric field control approach is currently possible on many existing products at a modest cost. Several techniques are available to provide the level of electric field control needed. Choosing the optimum technique depends on material, size, and surface accessibility. The simplest deposition method uses a standard electroless plating technique, but other metalization techniques include vapor and energetic deposition, plasma spraying, conductive painting, and other controlled coating methods.

Method for improving performance of highly stressed electrical insulating structures

DOEpatents

Wilson, Michael J.; Goerz, David A.

2002-01-01

Removing the electrical field from the internal volume of high-voltage structures; e.g., bushings, connectors, capacitors, and cables. The electrical field is removed from inherently weak regions of the interconnect, such as between the center conductor and the solid dielectric, and places it in the primary insulation. This is accomplished by providing a conductive surface on the inside surface of the principal solid dielectric insulator surrounding the center conductor and connects the center conductor to this conductive surface. The advantage of removing the electric fields from the weaker dielectric region to a stronger area improves reliability, increases component life and operating levels, reduces noise and losses, and allows for a smaller compact design. This electric field control approach is currently possible on many existing products at a modest cost. Several techniques are available to provide the level of electric field control needed. Choosing the optimum technique depends on material, size, and surface accessibility. The simplest deposition method uses a standard electroless plating technique, but other metalization techniques include vapor and energetic deposition, plasma spraying, conductive painting, and other controlled coating methods.

Toward Paradoxical Inconsistency in Electrostatics of Metallic Conductors

DTIC Science & Technology

Naturally, when dealing with fundamental problems, the V and V effort should include careful exploration and, if necessary, revision of the fundamentals...Current developments show a clear trend toward more serious efforts in validation and verification (V and V) of physical and engineering models...underlying the physics. With this understanding in mind, we review some fundamentals of the models of crystalline electric conductors and find a

Effects of particle size distribution in thick film conductors

NASA Technical Reports Server (NTRS)

Vest, R. W.

1983-01-01

Studies of particle size distribution in thick film conductors are discussed. The distribution of particle sizes does have an effect on fired film density but the effect is not always positive. A proper distribution of sizes is necessary, and while the theoretical models can serve as guides to selecting this proper distribution, improved densities can be achieved by empirical variations from the predictions of the models.

Analysis of the ITER central solenoid insert (CSI) coil stability tests

NASA Astrophysics Data System (ADS)

Savoldi, L.; Bonifetto, R.; Breschi, M.; Isono, T.; Martovetsky, N.; Ozeki, H.; Zanino, R.

2017-07-01

At the end of the test campaign of the ITER Central Solenoid Insert (CSI) coil in 2015, after 16,000 electromagnetic (EM) cycles, some tests were devoted to the study of the conductor stability, through the measurement of the Minimum Quench Energy (MQE). The tests were performed by means of an inductive heater (IH), located in the high-field region of the CSI and wrapped around the conductor. The calorimetric calibration of the IH is presented here, aimed at assessing the energy deposited in the conductor for different values of the IH electrical operating conditions. The MQE of the conductor of the ITER CS module 3L can be estimated as ∼200 J ± 20%, deposited on the whole conductor on a length of ∼10 cm (the IH length) in ∼40 ms, at current and magnetic field conditions relevant for the ITER CS operation. The repartition of the energy deposited in the conductor under the IH is computed to be ∼10% in the cable and 90% in the jacket by means of a 3D Finite Elements EM model. It is shown how this repartition implies that the bundle (cable + helium) heat capacity is fully available for stability on the time scale of the tested disturbances. This repartition is used in input to the thermal-hydraulic analysis performed with the 4C code, to assess the capability of the model to accurately reproduce the stability threshold of the conductor. The MQE computed by the code for this disturbance is in good agreement with the measured value, with an underestimation within 15% of the experimental value.

Thermal protection system ablation sensor

NASA Technical Reports Server (NTRS)

Gorbunov, Sergey (Inventor); Martinez, Edward R. (Inventor); Scott, James B. (Inventor); Oishi, Tomomi (Inventor); Fu, Johnny (Inventor); Mach, Joseph G. (Inventor); Santos, Jose B. (Inventor)

2011-01-01

An isotherm sensor tracks space vehicle temperatures by a thermal protection system (TPS) material during vehicle re-entry as a function of time, and surface recession through calibration, calculation, analysis and exposed surface modeling. Sensor design includes: two resistive conductors, wound around a tube, with a first end of each conductor connected to a constant current source, and second ends electrically insulated from each other by a selected material that becomes an electrically conductive char at higher temperatures to thereby complete an electrical circuit. The sensor conductors become shorter as ablation proceeds and reduced resistance in the completed electrical circuit (proportional to conductor length) is continually monitored, using measured end-to-end voltage change or current in the circuit. Thermocouple and/or piezoelectric measurements provide consistency checks on local temperatures.

Overheating instability of a thin conductor with respect to stratification

NASA Astrophysics Data System (ADS)

Garanin, S. F.; Kuznetsov, S. D.

2018-04-01

We consider an overheating instability of a thin (compared to the skin depth) conductor with respect to stratification at the stage when its resistivity rises up to an electrical explosion. Temperature perturbations under such conditions are shown to grow in proportion to resistivity. In the model, when resistivity is proportional to temperature, perturbations grow in proportion to temperature and hence exhibit no relative growth. For a conductor with initial thickness perturbations, temperature perturbations grow in proportion to resistivity and current action integral, i.e., somewhat faster than perturbations in the problem of constant thickness conductors. Comparison of our results with simulations of the growth of stratification during electrical heating of foils in warm dense matter generation systems demonstrates their close agreement.

Study and Experiment on Non-Contact Voltage Sensor Suitable for Three-Phase Transmission Line

PubMed Central

Zhou, Qiang; He, Wei; Xiao, Dongping; Li, Songnong; Zhou, Kongjun

2015-01-01

A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid. PMID:26729119

Study and Experiment on Non-Contact Voltage Sensor Suitable for Three-Phase Transmission Line.

PubMed

Zhou, Qiang; He, Wei; Xiao, Dongping; Li, Songnong; Zhou, Kongjun

2015-12-30

A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid.

Generation of synthetic surface electromyography signals under fatigue conditions for varying force inputs using feedback control algorithm.

PubMed

Venugopal, G; Deepak, P; Ghosh, Diptasree M; Ramakrishnan, S

2017-11-01

Surface electromyography is a non-invasive technique used for recording the electrical activity of neuromuscular systems. These signals are random, complex and multi-component. There are several techniques to extract information about the force exerted by muscles during any activity. This work attempts to generate surface electromyography signals for various magnitudes of force under isometric non-fatigue and fatigue conditions using a feedback model. The model is based on existing current distribution, volume conductor relations, the feedback control algorithm for rate coding and generation of firing pattern. The result shows that synthetic surface electromyography signals are highly complex in both non-fatigue and fatigue conditions. Furthermore, surface electromyography signals have higher amplitude and lower frequency under fatigue condition. This model can be used to study the influence of various signal parameters under fatigue and non-fatigue conditions.

Preparing the Conductor as Teacher

ERIC Educational Resources Information Center

Ulrich, Jerry

2009-01-01

While music is as old as humanity, conducting as a profession is relatively new. Although a nineteenth-century model has served as the template for the training of conductors, many undergraduate conducting students will spend their teaching careers working with inexperienced and/or amateur musicians. Additionally, the size of many ensembles in…

Transient interaction model of electromagnetic field generated by lightning current pulses and human body

NASA Astrophysics Data System (ADS)

Iváncsy, T.; Kiss, I.; Szücs, L.; Tamus, Z. Á.

2015-10-01

The lightning current generates time-varying magnetic field near the down- conductor and the down-conductors are mounted on the wall of the buildings where residential places might be situated. It is well known that the rapidly changing magnetic fields can generate dangerous eddy currents in the human body.The higher duration and gradient of the magnetic field can cause potentially life threatening cardiac stimulation. The coupling mechanism between the electromagnetic field and the human body is based on a well-known physical phenomena (e.g. Faradays law of induction). However, the calculation of the induced current is very complicated because the shape of the organs is complex and the determination of the material properties of living tissues is difficult, as well. Our previous study revealed that the cardiac stimulation is independent of the rising time of the lightning current and only the peak of the current counts. In this study, the authors introduce an improved model of the interaction of electromagnetic fields of lighting current near down-conductor and human body. Our previous models are based on the quasi stationer field calculations, the new improved model is a transient model. This is because the magnetic field around the down-conductor and in the human body can be determined more precisely, therefore the dangerous currents in the body can be estimated.

The Shock and Vibration Digest. Volume 18, Number 11

DTIC Science & Technology

1986-11-01

instantaneous clearances for various conductor loadings and weather conditions. Composite insulators are now more widely used. They consists...ter under gunfire. However, their electrical and mechanical behaviors are mote complicated than those of analogous porcelain insulators because...mechanical considerations by discussing recent research papets. Tensile tests on composite insulators have shown that short-term tensile

Transverse tripolar spinal cord stimulation: theoretical performance of a dual channel system.

PubMed

Struijk, J J; Holsheimer, J

1996-07-01

A new approach to spinal cord stimulation is presented, by which several serious problems of conventional methods can be solved. A transverse tripolar electrode with a dual-channel voltage stimulator is evaluated theoretically by means of a volume conductor model, combined with nerve fibre models. The simulations predict that a high degree of freedom in the control of activation of dorsal spinal pathways may be obtained with the described system. This implies an easier control of paraesthesia coverage of skin areas and the possibility to correct undesired paraesthesia patterns, caused by lead migration, tissue growth, or anatomical asymmetries, for example, without surgical intervention. It will also be possible to preferentially activate either dorsal column or dorsal root fibres, which has some important clinical advantages. Compared to conventional stimulation systems, the new system has a relatively high current drain.

Characterization of the ITER CS conductor and projection to the ITER CS performance

DOE PAGES

Martovetsky, N.; Isono, T.; Bessette, D.; ...

2017-06-20

The ITER Central Solenoid (CS) is one of the critical elements of the machine. The CS conductor went through an intense optimization and qualification program, which included characterization of the strands, a conductor straight short sample testing in the SULTAN facility at the Swiss Plasma Center (SPC), Villigen, Switzerland, and a single-layer CS Insert coil recently tested in the Central Solenoid Model Coil (CSMC) facility in QST-Naka, Japan. In this paper, we obtained valuable data in a wide range of the parameters (current, magnetic field, temperature, and strain), which allowed a credible characterization of the CS conductor in different conditions.more » Finally, using this characterization, we will make a projection to the performance of the CS in the ITER reference scenario.« less

Characterization of the ITER CS conductor and projection to the ITER CS performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martovetsky, N.; Isono, T.; Bessette, D.

The ITER Central Solenoid (CS) is one of the critical elements of the machine. The CS conductor went through an intense optimization and qualification program, which included characterization of the strands, a conductor straight short sample testing in the SULTAN facility at the Swiss Plasma Center (SPC), Villigen, Switzerland, and a single-layer CS Insert coil recently tested in the Central Solenoid Model Coil (CSMC) facility in QST-Naka, Japan. In this paper, we obtained valuable data in a wide range of the parameters (current, magnetic field, temperature, and strain), which allowed a credible characterization of the CS conductor in different conditions.more » Finally, using this characterization, we will make a projection to the performance of the CS in the ITER reference scenario.« less

Realistic modeling of deep brain stimulation implants for electromagnetic MRI safety studies.

PubMed

Guerin, Bastien; Serano, Peter; Iacono, Maria Ida; Herrington, Todd M; Widge, Alik S; Dougherty, Darin D; Bonmassar, Giorgio; Angelone, Leonardo M; Wald, Lawrence L

2018-05-04

We propose a framework for electromagnetic (EM) simulation of deep brain stimulation (DBS) patients in radiofrequency (RF) coils. We generated a model of a DBS patient using post-operative head and neck computed tomography (CT) images stitched together into a 'virtual CT' image covering the entire length of the implant. The body was modeled as homogeneous. The implant path extracted from the CT data contained self-intersections, which we corrected automatically using an optimization procedure. Using the CT-derived DBS path, we built a model of the implant including electrodes, helicoidal internal conductor wires, loops, extension cables, and the implanted pulse generator. We also built four simplified models with straight wires, no extension cables and no loops to assess the impact of these simplifications on safety predictions. We simulated EM fields induced by the RF birdcage body coil in the body model, including at the DBS lead tip at both 1.5 Tesla (64 MHz) and 3 Tesla (123 MHz). We also assessed the robustness of our simulation results by systematically varying the EM properties of the body model and the position and length of the DBS implant (sensitivity analysis). The topology correction algorithm corrected all self-intersection and curvature violations of the initial path while introducing minimal deformations (open-source code available at http://ptx.martinos.org/index.php/Main_Page). The unaveraged lead-tip peak SAR predicted by the five DBS models (0.1 mm resolution grid) ranged from 12.8 kW kg -1 (full model, helicoidal conductors) to 43.6 kW kg -1 (no loops, straight conductors) at 1.5 T (3.4-fold variation) and 18.6 kW kg -1 (full model, straight conductors) to 73.8 kW kg -1 (no loops, straight conductors) at 3 T (4.0-fold variation). At 1.5 T and 3 T, the variability of lead-tip peak SAR with respect to the conductivity ranged between 18% and 30%. Variability with respect to the position and length of the DBS implant ranged between 9.5% and 27.6%.

Realistic modeling of deep brain stimulation implants for electromagnetic MRI safety studies

NASA Astrophysics Data System (ADS)

Guerin, Bastien; Serano, Peter; Iacono, Maria Ida; Herrington, Todd M.; Widge, Alik S.; Dougherty, Darin D.; Bonmassar, Giorgio; Angelone, Leonardo M.; Wald, Lawrence L.

2018-05-01

We propose a framework for electromagnetic (EM) simulation of deep brain stimulation (DBS) patients in radiofrequency (RF) coils. We generated a model of a DBS patient using post-operative head and neck computed tomography (CT) images stitched together into a ‘virtual CT’ image covering the entire length of the implant. The body was modeled as homogeneous. The implant path extracted from the CT data contained self-intersections, which we corrected automatically using an optimization procedure. Using the CT-derived DBS path, we built a model of the implant including electrodes, helicoidal internal conductor wires, loops, extension cables, and the implanted pulse generator. We also built four simplified models with straight wires, no extension cables and no loops to assess the impact of these simplifications on safety predictions. We simulated EM fields induced by the RF birdcage body coil in the body model, including at the DBS lead tip at both 1.5 Tesla (64 MHz) and 3 Tesla (123 MHz). We also assessed the robustness of our simulation results by systematically varying the EM properties of the body model and the position and length of the DBS implant (sensitivity analysis). The topology correction algorithm corrected all self-intersection and curvature violations of the initial path while introducing minimal deformations (open-source code available at http://ptx.martinos.org/index.php/Main_Page). The unaveraged lead-tip peak SAR predicted by the five DBS models (0.1 mm resolution grid) ranged from 12.8 kW kg‑1 (full model, helicoidal conductors) to 43.6 kW kg‑1 (no loops, straight conductors) at 1.5 T (3.4-fold variation) and 18.6 kW kg‑1 (full model, straight conductors) to 73.8 kW kg‑1 (no loops, straight conductors) at 3 T (4.0-fold variation). At 1.5 T and 3 T, the variability of lead-tip peak SAR with respect to the conductivity ranged between 18% and 30%. Variability with respect to the position and length of the DBS implant ranged between 9.5% and 27.6%.

A job analysis design for the rail industry : description and model analysis of the job of freight conductor.

DOT National Transportation Integrated Search

2013-10-01

This document provides a step-by-step description of the design and execution of a strategic job analysis, using the position of Freight Conductor as an example. This document was created to be useful for many different needs, and can be used as an e...

A Classroom Activity for Teaching Electric Polarization of Insulators and Conductors

ERIC Educational Resources Information Center

Deligkaris, Christos

2018-01-01

The phenomenon of electric polarization is crucial to student understanding of forces exerted between charged objects and insulators or conductors, the process of charging by induction, and the behavior of electroscopes near charged objects. In addition, polarization allows for microscopic-level models of everyday-life macroscopic-level phenomena.…

Electrowetting on semiconductors

NASA Astrophysics Data System (ADS)

Palma, Cesar; Deegan, Robert

2015-01-01

Applying a voltage difference between a conductor and a sessile droplet sitting on a thin dielectric film separating it from the conductor will cause the drop to spread. When the conductor is a good metal, the change of the drop's contact angle due to the voltage is given by the Young-Lippmann (YL) equation. Here, we report experiments with lightly doped, single crystal silicon as the conductive electrode. We derive a modified YL equation that includes effects due to the semiconductor and contact line pinning. We show that light induces a non-reversible wetting transition, and that our model agrees well with our experimental results.

Comparison study and thoron interference test of different radon monitors.

PubMed

Sumesh, C G; Kumar, A Vinod; Tripathi, R M; Puranik, V D

2013-03-01

A comparison study and thoron interference test for different continuous radon monitors were carried out. The comparison study includes three passive diffusion monitors [one pulse ionisation chamber based-Alpha Guard and two silicon semi-conductor based-Radon Scout Plus (RSP)] and one silicon semi-conductor-based active radon thoron discriminating monitor--RAD 7. Radon emanation standard, supplied by National Institute of Science and Technology, has been utilised for the comparison study to qualify the calibration of the continuous radon monitors. All the instruments showed good agreement with the estimated radon concentration using (226)Ra/(222)Rn emanation standard. It was found that the active radon monitoring system is having a higher initial response towards the transient radon concentration than the passive radon monitors studied. The instruments measuring radon concentration without energy discrimination are likely to have some sensitivity towards the thoron concentration. Thus, thoron interference study was carried out in the above monitors. Nine percent interference in measured radon concentration in the Alpha Guard monitor and 4 % interference in the semi-conductor-based RSP monitors was observed. Study indicates that the interference of thoron in radon monitors depends on the area of diffusion of gas, volume of detection and sensitivity factor.

Promotional role of Li4Ti5O12 as polysulfide adsorbent and fast Li+ conductor on electrochemical performances of sulfur cathode

NASA Astrophysics Data System (ADS)

Zeng, Tianbiao; Hu, Xuebu; Ji, Penghui; Shang, Biao; Peng, Qimeng; Zhang, Yaoyao; Song, Ruiqiang

2017-08-01

Lithium-sulfur (Li-S) batteries attract much attention due to its high specific capacity and energy density compared to lithium-ion batteries (LiBs). Herein, a novel composite named as (void/nano-Li4Ti5O12 pieces)@C [(v/n-L)@C] was designed and prepared as a sulfur host. Spinel Li4Ti5O12 here as a multifunctional additive played as polysulfide adsorbent agent and fast Li+ conductor, and carbon shell was designed as electronic conductor, as well as volume barrier to limit the volume expansion caused by sulfur. As-prepared (S/nano-Li4Ti5O12 pieces)@C [(S/n-L)@C] are core-shell spheres, which are about 200 nm in size. Nano-Li4Ti5O12 and sulfur were coated by the outer carbon shell with a thickness of about 20 nm. The experimental results show that electrochemical performances of (S/n-L)@C cathode were enhanced effectively compared to S@C cathode. At 0.5C and 1C, the discharge capacity of (S/n-L)@C was 33.5% and 40.1% higher than that of S@C at 500th cycle. Even at 2C, its capacity reached 600.9 mAh g-1 at 1000th cycle. Li+ conductivity of (S/n-L)@C was one order of magnitude higher than that of S@C, which was reach to 2.55 × 10-8 S cm-1. The experiment results indicate Li4Ti5O12 plays a promotional role on electrochemical performances of sulfur cathode, especially for stable cycling performance and high rate performance.

Capacitance probe for fluid flow and volume measurements

NASA Technical Reports Server (NTRS)

Arndt, G. Dickey (Inventor); Nguyen, Thanh X. (Inventor); Carl, James R. (Inventor)

1995-01-01

Method and apparatus for making measurements on fluids are disclosed, including the use of a capacitive probe for measuring the flow volume of a material within a flow stream. The capacitance probe has at least two elongate electrodes and, in a specific embodiment of the invention, has three parallel elongate electrodes with the center electrode being an extension of the center conductor of a co-axial cable. A conductance probe is also provided to provide more accurate flow volume data in response to conductivity of the material within the flow stream. A preferred embodiment of the present invention provides for a gas flow stream through a microgravity environment that allows for monitoring a flow volume of a fluid sample, such as a urine sample, that is entrained within the gas flow stream.

Capacitance Probe for Fluid Flow and Volume Measurements

NASA Technical Reports Server (NTRS)

Arndt, G. Dickey (Inventor); Nguyen, Thanh X. (Inventor); Carl, James R. (Inventor)

1997-01-01

Method and apparatus for making measurements on fluids are disclosed, including the use of a capacitive probe for measuring the flow volume of a material within a flow stream. The capacitance probe has at least two elongate electrodes and, in a specific embodiment of the invention, has three parallel elongate electrodes with the center electrode being an extension of the center conductor of a co-axial cable. A conductance probe is also provided to provide more accurate flow volume data in response to conductivity of the material within the flow stream. A preferred embodiment of the present invention provides for a gas flow stream through a micro-gravity environment that allows for monitoring a flow volume of a fluid sample, such as a urine sample, that is entrained within the gas flow stream.

Theoretical performance and clinical evaluation of transverse tripolar spinal cord stimulation.

PubMed

Struijk, J J; Holsheimer, J; Spincemaille, G H; Gielen, F L; Hoekema, R

1998-09-01

A new type of spinal cord stimulation electrode, providing contact combinations with a transverse orientation, is presented. Electrodes were implanted in the cervical area (C4-C5) of two chronic pain patients and the stimulation results were subsequently simulated with a computer model consisting of a volume conductor model and active nerve fiber models. For various contact combinations a good match was obtained between the modeling results and the measurement data with respect to load resistance (less than 20% difference), perception thresholds (16% difference), asymmetry of paresthesia (significant correlation) and paresthesia distributions (weak correlation). The transversally oriented combinations provided the possibility to select either a preferential dorsal column stimulation, a preferential dorsal root stimulation or a mixed stimulation. The (a)symmetry of paresthesia could largely be affected in a predictable way by the selection of contact combinations as well. The transverse tripolar combination was shown to give a higher selectivity of paresthesia than monopolar and longitudinal dipolar combinations, at the cost of an increased current (more than twice).

The Chemical Modeling of Electronic Materials and Interconnections

NASA Astrophysics Data System (ADS)

Kivilahti, J. K.

2002-12-01

Thermodynamic and kinetic modeling, together with careful experimental work, is of great help for developing new electronic materials such as lead-free solders, their compatible metallizations and diffusion-barrier layers, as well as joining and bonding processes for advanced electronics manufacturing. When combined, these modeling techniques lead to a rationalization of the trial-and-error methods employed in the electronics industry, limiting experimentation and, thus, reducing significantly time-to-market of new products. This modeling provides useful information on the stabilities of phases (microstructures), driving forces for chemical reactions, and growth rates of reaction products occurring in interconnections or thin-film structures during processing, testing, and in longterm use of electronic devices. This is especially important when manufacturing advanced lead-free electronics where solder joint volumes are decreasing while the number of dissimilar reactive materials is increasing markedly. Therefore, a new concept of local nominal composition was introduced and applied together with the relevant ternary and multicomponent phase diagrams to some solder/conductor systems.

Finite Volume Methods: Foundation and Analysis

NASA Technical Reports Server (NTRS)

Barth, Timothy; Ohlberger, Mario

2003-01-01

Finite volume methods are a class of discretization schemes that have proven highly successful in approximating the solution of a wide variety of conservation law systems. They are extensively used in fluid mechanics, porous media flow, meteorology, electromagnetics, models of biological processes, semi-conductor device simulation and many other engineering areas governed by conservative systems that can be written in integral control volume form. This article reviews elements of the foundation and analysis of modern finite volume methods. The primary advantages of these methods are numerical robustness through the obtention of discrete maximum (minimum) principles, applicability on very general unstructured meshes, and the intrinsic local conservation properties of the resulting schemes. Throughout this article, specific attention is given to scalar nonlinear hyperbolic conservation laws and the development of high order accurate schemes for discretizing them. A key tool in the design and analysis of finite volume schemes suitable for non-oscillatory discontinuity capturing is discrete maximum principle analysis. A number of building blocks used in the development of numerical schemes possessing local discrete maximum principles are reviewed in one and several space dimensions, e.g. monotone fluxes, E-fluxes, TVD discretization, non-oscillatory reconstruction, slope limiters, positive coefficient schemes, etc. When available, theoretical results concerning a priori and a posteriori error estimates are given. Further advanced topics are then considered such as high order time integration, discretization of diffusion terms and the extension to systems of nonlinear conservation laws.

Influence of magnetic materials on the transport properties of superconducting composite conductors

NASA Astrophysics Data System (ADS)

Glowacki, B. A.; Majoros, M.; Campbell, A. M.; Hopkins, S. C.; Rutter, N. A.; Kozlowski, G.; Peterson, T. L.

2009-03-01

Magnetic materials can help to improve the performance of practical superconductors on the macro/microscale as magnetic diverters and also on the nanoscale as effective pinning centres. It has been established by numerical modelling that magnetic shielding of the filaments reduces ac losses in self-field conditions due to decoupling of the filaments and, at the same time, it increases the critical current of the composite. This effect is especially beneficial for coated conductors, in which the anisotropic properties of the superconductor are amplified by the conductor architecture. However, ferromagnetic coatings are often chemically incompatible with YBa2Cu3O7 and (Pb,Bi)2Sr2Ca2Cu3O9 conductors, and buffer layers have to be used. In contrast, in MgB2 conductors an iron matrix may remain in direct contact with the superconducting core. The application of superconducting-magnetic heterostructures requires consideration of the thermal and electromagnetic stability of the superconducting materials used. On the one hand, magnetic components reduce the critical current gradient across the individual filaments but, on the other hand, they often reduce the thermal conductivity between the superconducting core and the cryogen, which may cause the destruction of the conductor in the event of thermal instability. A possible nanoscale method of improving the critical current density of superconducting conductors is the introduction of sub-micron magnetic pinning centres. However, the volumetric density and chemical compatibility of magnetic inclusions has to be controlled to avoid suppression of the superconducting properties.

The Design and Operation of Ultra-Sensitive and Tunable Radio-Frequency Interferometers.

PubMed

Cui, Yan; Wang, Pingshan

2014-12-01

Dielectric spectroscopy (DS) is an important technique for scientific and technological investigations in various areas. DS sensitivity and operating frequency ranges are critical for many applications, including lab-on-chip development where sample volumes are small with a wide range of dynamic processes to probe. In this work, we present the design and operation considerations of radio-frequency (RF) interferometers that are based on power-dividers (PDs) and quadrature-hybrids (QHs). Such interferometers are proposed to address the sensitivity and frequency tuning challenges of current DS techniques. Verified algorithms together with mathematical models are presented to quantify material properties from scattering parameters for three common transmission line sensing structures, i.e., coplanar waveguides (CPWs), conductor-backed CPWs, and microstrip lines. A high-sensitivity and stable QH-based interferometer is demonstrated by measuring glucose-water solution at a concentration level that is ten times lower than some recent RF sensors while our sample volume is ~1 nL. Composition analysis of ternary mixture solutions are also demonstrated with a PD-based interferometer. Further work is needed to address issues like system automation, model improvement at high frequencies, and interferometer scaling.

The Influence of Music Style and Conductor Race on Perceptions of Ensemble and Conductor Performance

ERIC Educational Resources Information Center

Vanweelden, Kimberly; McGee, Isaiah R.

2007-01-01

The purpose of this study was to examine music style and conductor race on perceptions of ensemble and conductor performance. Results found that conductor race and music style significantly affected ratings of ensemble and conductor performance. Evaluators rated a white conductor group higher than a black conductor group conducting the same…

3-D interpretation of short-period magnetotelluric data at Furnas Volcano, Azores Islands

NASA Astrophysics Data System (ADS)

Hogg, C.; Kiyan, D.; Rath, V.; Byrdina, S.; Vandemeulebrouck, J.; Revil, A.; Viveiros, F.; Carmo, R.; Silva, C.; Ferreira, T.

2018-04-01

Accurate geophysical imaging of shallow subsurface features provides crucial constraints on understanding the dynamics of volcanic systems. At Furnas Volcano (Azores), intense circulation of volcanic fluids at depth leading to high CO2 outgassing and flank destabilization poses considerable threat to the local population. Presented is a novel 3-D electrical resistivity model developed from 39 magnetotelluric soundings that images the hydrothermal system of the Furnas Volcano to a depth of 1 km. The resistivity model images two conductive zones, one at 100 m and another at 500 m depth, separated by a resistive layer. The shallow conductor has conductivity less than 1 S m-1, which can be explained by clay mineral surface conduction with a mass fraction of at least 20 per cent smectite. The deeper conductor extends across the majority of the survey area. This deeper conductor is located at depths where smectite is generally replaced by chlorite and we interpret it as aqueous fluids near the boiling point and infer temperatures of at least 240 °C. The less conductive layer found between these conductors is probably steam-dominated, and coincides within the mixed-clay zone found in many volcanic hydrothermal systems.

Circular Array of Magnetic Sensors for Current Measurement: Analysis for Error Caused by Position of Conductor.

PubMed

Yu, Hao; Qian, Zheng; Liu, Huayi; Qu, Jiaqi

2018-02-14

This paper analyzes the measurement error, caused by the position of the current-carrying conductor, of a circular array of magnetic sensors for current measurement. The circular array of magnetic sensors is an effective approach for AC or DC non-contact measurement, as it is low-cost, light-weight, has a large linear range, wide bandwidth, and low noise. Especially, it has been claimed that such structure has excellent reduction ability for errors caused by the position of the current-carrying conductor, crosstalk current interference, shape of the conduction cross-section, and the Earth's magnetic field. However, the positions of the current-carrying conductor-including un-centeredness and un-perpendicularity-have not been analyzed in detail until now. In this paper, for the purpose of having minimum measurement error, a theoretical analysis has been proposed based on vector inner and exterior product. In the presented mathematical model of relative error, the un-center offset distance, the un-perpendicular angle, the radius of the circle, and the number of magnetic sensors are expressed in one equation. The comparison of the relative error caused by the position of the current-carrying conductor between four and eight sensors is conducted. Tunnel magnetoresistance (TMR) sensors are used in the experimental prototype to verify the mathematical model. The analysis results can be the reference to design the details of the circular array of magnetic sensors for current measurement in practical situations.

Temperature limited heater utilizing non-ferromagnetic conductor

DOEpatents

Vinegar,; Harold J. , Harris; Kelvin, Christopher [Houston, TX

2012-07-17

A heater is described. The heater includes a ferromagnetic conductor and an electrical conductor electrically coupled to the ferromagnetic conductor. The ferromagnetic conductor is positioned relative to the electrical conductor such that an electromagnetic field produced by time-varying current flow in the ferromagnetic conductor confines a majority of the flow of the electrical current to the electrical conductor at temperatures below or near a selected temperature.

TPX: Contractor preliminary design review. Volume 3, Design and analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-06-30

Several models have been formed for investigating the maximum electromagnetic loading and magnetic field levels associated with the Tokamak Physics eXperiment (TPX) superconducting Poloidal Field (PF) coils. The analyses have been performed to support the design of the individual fourteen hoop coils forming the PF system. The coils have been sub-divided into three coil systems consisting of the central solenoid (CS), PF5 coils, and the larger radius PF6 and PF7 coils. Various electromagnetic analyses have been performed to determine the electromagnetic loadings that the coils will experience during normal operating conditions, plasma disruptions, and fault conditions. The loadings are presentedmore » as net body forces acting individual coils, spatial variations throughout the coil cross section, and force variations along the path of the conductor due to interactions with the TF coils. Three refined electromagnetic models of the PF coil system that include a turn-by-turn description of the fields and forces during a worst case event are presented in this report. A global model including both the TF and PF system was formed to obtain the force variations along the path of the PF conductors resulting from interactions with the TF currents. In addition to spatial variations, the loadings are further subdivided into time-varying and steady components so that structural fatigue issues can be addressed by designers and analysts. Other electromagnetic design issues such as the impact of the detailed coil designs on field errors are addressed in this report. Coil features that are analyzed include radial transitions via short jogs vs. spiral type windings and the effects of layer-to-layer rotations (i.e clocking) on the field errors.« less

Superconducting-magnetic heterostructures: a method of decreasing AC losses and improving critical current density in multifilamentary conductors

NASA Astrophysics Data System (ADS)

Glowacki, B. A.; Majoros, M.

2009-06-01

Magnetic materials can help to improve the performance of practical superconductors on the macroscale/microscale as magnetic diverters and also on the nanoscale as effective pinning centres. It has been established by numerical modelling that magnetic shielding of the filaments reduces AC losses in self-field conditions due to decoupling of the filaments and, at the same time, it increases the critical current of the composite. This effect is especially beneficial for coated conductors, in which the anisotropic properties of the superconductor are amplified by the conductor architecture. However, ferromagnetic coatings are often chemically incompatible with YBa2Cu3O7 and (Pb,Bi)2Sr2Ca2Cu3O9 conductors, and buffer layers have to be used. In contrast, in MgB2 conductors an iron matrix may remain in direct contact with the superconducting core. The application of superconducting-magnetic heterostructures requires consideration of the thermal and electromagnetic stability of the superconducting materials used. On one hand, magnetic materials reduce the critical current gradient across the individual filaments but, on the other hand, they often reduce the thermal conductivity between the superconducting core and the cryogen, which may cause destruction of the conductor in the event of thermal instability. A possible nanoscale method of improving the critical current density of superconducting conductors is the introduction of sub-micron magnetic pinning centres. However, the volumetric density and chemical compatibility of magnetic inclusions has to be controlled to avoid suppression of the superconducting properties.

Shielding effectiveness of multiple-shield cables with arbitrary terminations via transmission line analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campione, Salvatore; Basilio, Lorena I.; Warne, Larry Kevin

Our paper reports on a transmission-line model for calculating the shielding effectiveness of multiple-shield cables with arbitrary terminations. Since the shields are not perfect conductors and apertures in the shields permit external magnetic and electric fields to penetrate into the interior regions of the cable, we use this model to estimate the effects of the outer shield current and voltage (associated with the external excitation and boundary conditions associated with the external conductor) on the inner conductor current and voltage. It is commonly believed that increasing the number of shields of a cable will improve the shielding performance. But thismore » is not always the case, and a cable with multiple shields may perform similar to or worse than a cable with a single shield. Furthermore, we want to shed more light on these situations, which represent the main focus of this paper.« less

Shielding effectiveness of multiple-shield cables with arbitrary terminations via transmission line analysis

DOE PAGES

Campione, Salvatore; Basilio, Lorena I.; Warne, Larry Kevin; ...

2016-06-25

Our paper reports on a transmission-line model for calculating the shielding effectiveness of multiple-shield cables with arbitrary terminations. Since the shields are not perfect conductors and apertures in the shields permit external magnetic and electric fields to penetrate into the interior regions of the cable, we use this model to estimate the effects of the outer shield current and voltage (associated with the external excitation and boundary conditions associated with the external conductor) on the inner conductor current and voltage. It is commonly believed that increasing the number of shields of a cable will improve the shielding performance. But thismore » is not always the case, and a cable with multiple shields may perform similar to or worse than a cable with a single shield. Furthermore, we want to shed more light on these situations, which represent the main focus of this paper.« less

Conductor for a fluid-cooled winding

DOEpatents

Kenney, Walter J.

1983-01-01

A conductor and method of making the conductor are provided for use in winding electrical coils which are cooled by a fluid communicating with the conductor. The conductor is cold worked through twisting and reshaping steps to form a generally rectangular cross section conductor having a plurality of helical cooling grooves extending axially of the conductor. The conductor configuration makes it suitable for a wide variety of winding applications and permits the use of simple strip insulation between turns and perforated sheet insulation between layers of the winding.

Semi-flexible gas-insulated transmission line using sandwiched discs for intermittent flexing joints

DOEpatents

Kommineni, P.R.

1983-02-15

A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by the use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements are formed by sandwiching together, by fusing, a pair of thin hollow discs which are fixedly secured to both the main conductor sections and the conductor hub section. 4 figs.

Z a Fast Pulsed Power Generator for Ultra-High Magnetic Field Generation

NASA Astrophysics Data System (ADS)

Spielman, R. B.; Stygar, W. A.; Struve, K. W.; Asay, J. R.; Hall, C. A.; Bernard, M. A.; Bailey, J. E.; McDaniel, D. H.

2004-11-01

Advances in fast, pulsed-power technologies have resulted in the development of very high current drivers that have current rise times ~100 ns. The largest such pulsed power driver today is the new Z accelerator located at Sandia National Laboratories in Albuquerque, New Mexico. Z can deliver more than 20 MA with a time-to-peak of 105 ns to low inductance (~1 nH) loads. Such large drivers are capable of directly generating magnetic fields approaching 3 kT in small, 1 cm3 volumes. In addition to direct field generation, Z can be used to compress an applied, axial seed field with a plasma. Flux compression schemes are not new and are, in fact, the basis of all explosive flux-compression generators, but we propose the use of plasma armatures rather than solid, conducting armatures. We present experimental results from the Z accelerator in which magnetic fields of ~2 kT are generated and measured with several diagnostics. Issues such as energy loss in solid conductors and dynamic response of current-carrying conductors to very large magnetic fields are reviewed in context with Z experiments. We describe planned flux-compression experiments that are expected to create the highest-magnitude uniform-field volumes yet attained in the laboratory.

The dynamic resistance of YBCO coated conductor wire: effect of DC current magnitude and applied field orientation

NASA Astrophysics Data System (ADS)

Jiang, Zhenan; Zhou, Wei; Li, Quan; Yao, Min; Fang, Jin; Amemiya, Naoyuki; Bumby, Chris W.

2018-07-01

Dynamic resistance, which occurs when a HTS coated conductor carries a DC current under an AC magnetic field, can have critical implications for the design of HTS machines. Here, we report measurements of dynamic resistance in a commercially available SuperPower 4 mm-wide YBCO coated conductor, carrying a DC current under an applied AC magnetic field of arbitrary orientation. The reduced DC current, I t/I c0, ranged from 0.01 to 0.9, where I t is the DC current level and I c0 is the self-field critical current of the conductor. The field angle (the angle between the magnetic field and the normal vector of the conductor wide-face) was varied between 0° and 90° at intervals of 10°. We show that the effective width of the conductor under study is ˜12% less than the physical wire width, and we attribute this difference to edge damage of the wire during or after manufacture. We then examine the measured dynamic resistance of this wire under perpendicular applied fields at very low DC current levels. In this regime we find that the threshold field, B th, of the conductor is well described by the nonlinear equation of Mikitik and Brandt. However, this model consistently underestimates the threshold field at higher current levels. As such, the dynamic resistance in a coated conductor under perpendicular magnetic fields is best described using two different equations for each of the low and high DC current regimes, respectively. At low DC currents where I t/I c0 ≤ 0.1, the nonlinear relationship of Mikitik and Brandt provides the closest agreement with experimental data. However, in the higher current regime where I t/I c0 ≥ 0.2, closer agreement is obtained using a simple linear expression which assumes a current-independent penetration field. We further show that for the conductor studied here, the measured dynamic resistance at different field angles is dominated by the perpendicular magnetic field component, with negligible contribution from the parallel component. Our findings now enable the dynamic resistance of a single conductor to be analytically determined for a very wide range of DC currents and at all applied field angles.

Systems and methods for selective hydrogen transport and measurement

DOEpatents

Glatzmaier, Gregory C

2013-10-29

Systems and methods for selectively removing hydrogen gas from a hydrogen-containing fluid volume are disclosed. An exemplary system includes a proton exchange membrane (PEM) selectively permeable to hydrogen by exclusively conducting hydrogen ions. The system also includes metal deposited as layers onto opposite sides or faces of the PEM to form a membrane-electrode assembly (MEA), each layer functioning as an electrode so that the MEA functions as an electrochemical cell in which the ionic conductors are hydrogen ions, and the MEA functioning as a hydrogen selective membrane (HSM) when located at the boundary between a hydrogen-containing fluid volume and a second fluid.

Depth Estimates for Slingram Electromagnetic Anomalies from Dipping Sheet-like Bodies by the Normalized Full Gradient Method

NASA Astrophysics Data System (ADS)

Dondurur, Derman

2005-11-01

The Normalized Full Gradient (NFG) method was proposed in the mid 1960s and was generally used for the downward continuation of the potential field data. The method eliminates the side oscillations which appeared on the continuation curves when passing through anomalous body depth. In this study, the NFG method was applied to Slingram electromagnetic anomalies to obtain the depth of the anomalous body. Some experiments were performed on the theoretical Slingram model anomalies in a free space environment using a perfectly conductive thin tabular conductor with an infinite depth extent. The theoretical Slingram responses were obtained for different depths, dip angles and coil separations, and it was observed from NFG fields of the theoretical anomalies that the NFG sections yield the depth information of top of the conductor at low harmonic numbers. The NFG sections consisted of two main local maxima located at both sides of the central negative Slingram anomalies. It is concluded that these two maxima also locate the maximum anomaly gradient points, which indicates the depth of the anomaly target directly. For both theoretical and field data, the depth of the maximum value on the NFG sections corresponds to the depth of the upper edge of the anomalous conductor. The NFG method was applied to the in-phase component and correct depth estimates were obtained even for the horizontal tabular conductor. Depth values could be estimated with a relatively small error percentage when the conductive model was near-vertical and/or the conductor depth was larger.

Audio-magnetotelluric investigation of sulfide mineralization in Proterozoic-Archean greenstone belts of Eastern Indian Craton

NASA Astrophysics Data System (ADS)

Singh, Shailendra; Maurya, Ved P.; Singh, Roshan K.; Srivastava, Shalivahan; Tripathi, Anurag; Adhikari, P. K.

2018-04-01

Greenstone belts are well known for gold occurrences at different regions of the world. The Dhanjori basin in the eastern Singhbhum region shows major characteristics of a rifted greenstone belt. Initially, we conducted 14 audio-magnetotelluric (AMT) measurements for a profile of ˜ 20 km in the frequency range of 1 kHz to 10 Hz over this rather complex geologic environment covering Dhanjori Volcanics (DhV) and Kolhan Group (KG). Subsequently, gravity and magnetic surveys were also conducted over this AMT profile. The purpose of the survey was to identify and map conductive features and to relate them to metallogeny of the area along with the mapping of the basement of Dhanjori basin. The strike analysis showed N30°W strike for DhV for all the frequencies and for sites over KG domain in the frequency range of 100-10 Hz, but for KG domain, the obtained strike in 1 kHz to 100 Hz is N45°E. As the combination of transverse electric (TE), transverse magnetic (TM) and tipper (Tzy) can recover the electrical signature in complex geological environment, we discuss the conductivity model obtained from TE+TM+Tzy only. The inversion was carried for the regional profile with 14 sites and for 7 sites over KG domain. Conductivity model shows two well resolved conductors, one each in KG and Quartz Pebble Conglomerate Dhanjori (QPCD) domains respectively showing common linked concordant features between these regional and KG profiles. The conductors are interpreted as sulfide mineralization linked with QPCD group of rocks which may host gold. These conductors are also horizontally disposed due to the intrusive younger Mayurbhanj Granite. These intrusives correlate well with the gravity modeling as well. The thickness of the Dhanjori basin at the central is about 3.0 km, similar to that from gravity modeling. The conductivity model also indicates the presence of shallow conductors, but could not be resolved due to lack of high frequency data. However, the results from the close-by drill site indicate the presence of shallow sulfide mineralization hosting gold. The deep level conductors delineated from AMT studies are associated with gravity high and low magnetic. ICP-AES results of Dhanjori samples show significant concentration of gold ˜ 5.0 g/t, which is of economic consideration. Thus, it can be inferred that the conductors have evidences of sulfide mineralization which host gold.

46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Equipment safety grounding (bonding) conductors. 111.05... § 111.05-33 Equipment safety grounding (bonding) conductors. (a) Each equipment-grounding conductor must... 110.10-1). (b) Each equipment-grounding conductor (other than a system-grounding conductor) of a cable...

46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Equipment safety grounding (bonding) conductors. 111.05... § 111.05-33 Equipment safety grounding (bonding) conductors. (a) Each equipment-grounding conductor must... 110.10-1). (b) Each equipment-grounding conductor (other than a system-grounding conductor) of a cable...

Semi-flexible gas-insulated transmission line using protection tube in conductor plug-in joint

DOEpatents

Kommineni, P.R.

1983-01-25

A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. A plug and socket arrangement is utilized for joining adjacent sections of the inner conductor, and a protection tube is utilized inside the hollow plug to maintain proper alignment of the joint when the transmission line is bent. 3 figs.

Semi-flexible gas-insulated transmission line using protection tube in conductor plug-in joint

DOEpatents

Kommineni, Prasad R.

1983-01-25

A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. A plug and socket arrangement is utilized for joining adjacent sections of the inner conductor, and a protection tube is utilized inside the hollow plug to maintain proper alignment of the joint when the transmission line is bent.

Terminal structure

DOEpatents

Schmidt, Frank [Langenhagen, DE; Allais, Arnaud [Hannover, DE; Mirebeau, Pierre [Villebon sur Yvette, FR; Ganhungu, Francois [Vieux-Reng, FR; Lallouet, Nicolas [Saint Martin Boulogne, FR

2009-10-20

A terminal structure (2) for a superconducting cable (1) is described. It consists of a conductor (2a) and an insulator (2b) that surrounds the conductor (2a), wherein the superconducting cable (1) has a core with a superconducting conductor (5) and a layer of insulation that surrounds the conductor (5), and wherein the core is arranged in such a way that it can move longitudinally in a cryostat. The conductor (2a) of the terminal structure (2) is electrically connected with the superconducting conductor (5) or with a normal conductor (6) that is connected with the superconducting conductor (5) by means of a tubular part (7) made of an electrically conductive material, wherein the superconducting conductor (5) or the normal conductor (6) can slide in the part (7) in the direction of the superconductor.

Electromagnetic analysis of a superconducting transformer for high current characterization of cable in conduit conductors in background magnetic field

NASA Astrophysics Data System (ADS)

Wu, Xiangyang; Tan, Yunfei; Fang, Zhen; Jiang, Donghui; Chen, Zhiyou; Chen, Wenge; Kuang, Guangli

2017-10-01

A large cable-in-conduit-conductor (CICC) test facility has been designed and fabricated at the High Magnetic Field Laboratory of the Chinese Academy of Sciences (CHMFL) in order to meet the test requirement of the conductors which are applied to the future fusion reactor. The critical component of the test facility is an 80 kA superconducting transformer which consists of a multi-turn primary coil and a minor-turn secondary coil. As the current source of the conductor samples, the electromagnetic performance of the superconducting transformer determines the stability and safety of the test facility. In this paper, the key factors and parameters, which have much impact on the performance of the transformer, are analyzed in detail. The conceptual design and optimizing principles of the transformer are discussed. An Electromagnetic-Circuit coupled model built in ANSYS Multiphysics is successfully used to investigate the electromagnetic characterization of the transformer under the dynamic operation condition.

Self-Consistent Theory of Shot Noise Suppression in Ballistic Conductors

NASA Astrophysics Data System (ADS)

Bulashenko, O. M.; Rubí, J. M.; Kochelap, V. A.

Shot-noise measurements become a fundamental tool to probe carrier interactions in mesoscopic systems [1]. A matter of particular interest is the significance of Coulomb interaction which may keep nearby electrons more regularly spaced rather than strictly at random and lead to the noise reduction. That effect occurs in different physical situations. Among them are charge-limited ballistic transport, resonant tunneling, single-electron tunneling, etc. In this communication we address the problem of Coulomb correlations in ballistic conductors under the space-charge-limited transport conditions, and present for the first time a semiclassical self-consistent theory of shot noise in these conductors by solving analytically the kinetic equation coupled self-consistently with a Poisson equation. Basing upon this theory, exact results for current noise in a two-terminal ballistic conductor under the action of long-range Coulomb correlations has been derived. The noise reduction factor (in respect to the uncorrelated value) is obtained in a closed analytical form for a full range of biases ranging from thermal to shot-noise limits which describe perfectly the results of the Monte Carlo simulations for a nondegenerate electron gas [2]. The magnitude of the noise reduction exceeds 0.01, which is of interest from the point of view of possible applications. Using these analytical results one may estimate a relative contribution to the noise from different groups of carriers (in energy space and/or real space) and to investigate in great detail the correlations between different groups of carriers. This leads us to suggest an electron energy spectroscopy experiment to probe the Coulomb correlations in ballistic conductors. Indeed, while the injected carriers are uncorrelated, those in the volume of the conductor are strongly correlated, as follows from the derived formulas for the fluctuation of the distribution function. Those correlations may be observed experimentally by making use of a combination of two already realized techniques: a hot-electron spectrometer [3,4] which allows one to analyze different energy groups of electrons collected at the contact and shot-noise measurements [5,6]. Such "shot noise reduction spectroscopy" allows one to measure the novel phenomena. In particular, we predict the (anti)correlation of the "tangent" electrons having the energy close to the potential barrier height, to all other electron energy groups collected at the receiving contact.

Overview of the hydraulic characteristics of the ITER Central Solenoid Model Coil conductors after 15 years of test campaigns

NASA Astrophysics Data System (ADS)

Brighenti, A.; Bonifetto, R.; Isono, T.; Kawano, K.; Russo, G.; Savoldi, L.; Zanino, R.

2017-12-01

The ITER Central Solenoid Model Coil (CSMC) is a superconducting magnet, layer-wound two-in-hand using Nb3Sn cable-in-conduit conductors (CICCs) with the central channel typical of ITER magnets, cooled with supercritical He (SHe) at ∼4.5 K and 0.5 MPa, operating for approximately 15 years at the National Institutes for Quantum and Radiological Science and Technology in Naka, Japan. The aim of this work is to give an overview of the issues related to the hydraulic performance of the three different CICCs used in the CSMC based on the extensive experimental database put together during the past 15 years. The measured hydraulic characteristics are compared for the different test campaigns and compared also to those coming from the tests of short conductor samples when available. It is shown that the hydraulic performance of the CSMC conductors did not change significantly in the sequence of test campaigns with more than 50 cycles up to 46 kA and 8 cooldown/warmup cycles from 300 K to 4.5 K. The capability of the correlations typically used to predict the friction factor of the SHe for the design and analysis of ITER-like CICCs is also shown.

Generation of field potentials and modulation of their dynamics through volume integration of cortical activity.

PubMed

Kajikawa, Yoshinao; Schroeder, Charles E

2015-01-01

Field potentials (FPs) recorded within the brain, often called "local field potentials" (LFPs), are useful measures of net synaptic activity in a neuronal ensemble. However, due to volume conduction, FPs spread beyond regions of underlying synaptic activity, and thus an "LFP" signal may not accurately reflect the temporal patterns of synaptic activity in the immediately surrounding neuron population. To better understand the physiological processes reflected in FPs, we explored the relationship between the FP and its membrane current generators using current source density (CSD) analysis in conjunction with a volume conductor model. The model provides a quantitative description of the spatiotemporal summation of immediate local and more distant membrane currents to produce the FP. By applying the model to FPs in the macaque auditory cortex, we have investigated a critical issue that has broad implications for FP research. We have shown that FP responses in particular cortical layers are differentially susceptible to activity in other layers. Activity in the supragranular layers has the strongest contribution to FPs in other cortical layers, and infragranular FPs are most susceptible to contributions from other layers. To define the physiological processes generating FPs recorded in loci of relatively weak synaptic activity, strong effects produced by synaptic events in the vicinity have to be taken into account. While outlining limitations and caveats inherent to FP measurements, our results also suggest specific peak and frequency band components of FPs can be related to activity in specific cortical layers. These results may help improving the interpretability of FPs. Copyright © 2015 the American Physiological Society.

Generation of field potentials and modulation of their dynamics through volume integration of cortical activity

PubMed Central

Schroeder, Charles E.

2014-01-01

Field potentials (FPs) recorded within the brain, often called “local field potentials” (LFPs), are useful measures of net synaptic activity in a neuronal ensemble. However, due to volume conduction, FPs spread beyond regions of underlying synaptic activity, and thus an “LFP” signal may not accurately reflect the temporal patterns of synaptic activity in the immediately surrounding neuron population. To better understand the physiological processes reflected in FPs, we explored the relationship between the FP and its membrane current generators using current source density (CSD) analysis in conjunction with a volume conductor model. The model provides a quantitative description of the spatiotemporal summation of immediate local and more distant membrane currents to produce the FP. By applying the model to FPs in the macaque auditory cortex, we have investigated a critical issue that has broad implications for FP research. We have shown that FP responses in particular cortical layers are differentially susceptible to activity in other layers. Activity in the supragranular layers has the strongest contribution to FPs in other cortical layers, and infragranular FPs are most susceptible to contributions from other layers. To define the physiological processes generating FPs recorded in loci of relatively weak synaptic activity, strong effects produced by synaptic events in the vicinity have to be taken into account. While outlining limitations and caveats inherent to FP measurements, our results also suggest specific peak and frequency band components of FPs can be related to activity in specific cortical layers. These results may help improving the interpretability of FPs. PMID:25274348

Semi-flexible gas-insulated transmission line using electric field stress shields

DOEpatents

Cookson, Alan H.; Dale, Steinar J.; Bolin, Philip C.

1982-12-28

A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements and the stress shields may also be utilized in connection with a plug and socket arrangement for providing electrical connection between main conductor sections.

Conductor and joint test results of JT-60SA CS and EF coils using the NIFS test facility

NASA Astrophysics Data System (ADS)

Obana, Tetsuhiro; Takahata, Kazuya; Hamaguchi, Shinji; Kizu, Kaname; Murakami, Haruyuki; Chikaraishi, Hirotaka; Noguchi, Hiroki; Kobuchi, Takashi; Moriuchi, Sadatomo; Imagawa, Shinsaku; Mito, Toshiyuki; Tsuchiya, Katsuhiko; Natsume, Kyohei; Yoshida, Kiyoshi; Nomoto, Kazuhiro; Kim, Tae-hyun

2016-01-01

In 2007, JAEA and NIFS launched the test project to evaluate the performance of cable-in-conduit (CIC) conductors and conductor joints for the JT-60SA CS and EF coils. In this project, conductor tests for four types of coil conductor and joint tests for seven types of conductor joint have been conducted for the past eight years using the NIFS test facility. As a result, the test project indicated that the CIC conductors and conductor joints fulfill the design requirement for the CS and EF coils. In addition, the NIFS test facility is expected to be utilized as the test facility for the development of a conductor and conductor joint for the purpose of the DEMO nuclear fusion power plant, provided that the required magnetic field strength is within 9 T.

Thermal conductor for high-energy electrochemical cells

DOEpatents

Hoffman, Joseph A.; Domroese, Michael K.; Lindeman, David D.; Radewald, Vern E.; Rouillard, Roger; Trice, Jennifer L.

2000-01-01

A thermal conductor for use with an electrochemical energy storage device is disclosed. The thermal conductor is attached to one or both of the anode and cathode contacts of an electrochemical cell. A resilient portion of the conductor varies in height or position to maintain contact between the conductor and an adjacent wall structure of a containment vessel in response to relative movement between the conductor and the wall structure. The thermal conductor conducts current into and out of the electrochemical cell and conducts thermal energy between the electrochemical cell and thermally conductive and electrically resistive material disposed between the conductor and the wall structure. The thermal conductor may be fabricated to include a resilient portion having one of a substantially C-shaped, double C-shaped, Z-shaped, V-shaped, O-shaped, S-shaped, or finger-shaped cross-section. An elastomeric spring element may be configured so as to be captured by the resilient conductor for purposes of enhancing the functionality of the thermal conductor. The spring element may include a protrusion that provides electrical insulation between the spring conductor and a spring conductor of an adjacently disposed electrochemical cell in the presence of relative movement between the cells and the wall structure. The thermal conductor may also be fabricated from a sheet of electrically conductive material and affixed to the contacts of a number of electrochemical cells.

46 CFR 111.05-31 - Grounding conductors for systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Grounding conductors for systems. 111.05-31 Section 111... Grounding conductors for systems. (a) A conductor for grounding a direct-current system must be the larger of: (1) The largest conductor supplying the system; or (2) No. 8 AWG (8.4mm2). (b) A conductor for...

46 CFR 111.05-31 - Grounding conductors for systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Grounding conductors for systems. 111.05-31 Section 111... Grounding conductors for systems. (a) A conductor for grounding a direct-current system must be the larger of: (1) The largest conductor supplying the system; or (2) No. 8 AWG (8.4mm2). (b) A conductor for...

Semi-flexible gas-insulated transmission line using electric field stress shields

DOEpatents

Cookson, A.H.; Dale, S.J.; Bolin, P.C.

1982-12-28

A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements and the stress shields may also be utilized in connection with a plug and socket arrangement for providing electrical connection between main conductor sections. 10 figs.

Moment method analysis of linearly tapered slot antennas

NASA Technical Reports Server (NTRS)

Koeksal, Adnan

1993-01-01

A method of moments (MOM) model for the analysis of the Linearly Tapered Slot Antenna (LTSA) is developed and implemented. The model employs an unequal size rectangular sectioning for conducting parts of the antenna. Piecewise sinusoidal basis functions are used for the expansion of conductor current. The effect of the dielectric is incorporated in the model by using equivalent volume polarization current density and solving the equivalent problem in free-space. The feed section of the antenna including the microstripline is handled rigorously in the MOM model by including slotline short circuit and microstripline currents among the unknowns. Comparison with measurements is made to demonstrate the validity of the model for both the air case and the dielectric case. Validity of the model is also verified by extending the model to handle the analysis of the skew-plate antenna and comparing the results to those of a skew-segmentation modeling results of the same structure and to available data in the literature. Variation of the radiation pattern for the air LTSA with length, height, and taper angle is investigated, and the results are tabulated. Numerical results for the effect of the dielectric thickness and permittivity are presented.

Modeling for intra-body communication with bone effect.

PubMed

Pun, S H; Gao, Y M; Mak, P U; Du, M; Vai, M I

2009-01-01

Intra-body communication (IBC) is a new, different "wireless" communication technique based on the human tissue. This short range "wireless" communication technology provides an alternative solution to wearable sensors, home health system, telemedicine and implanted devices. The development of the IBC enables the possibilities of providing less complexity and convenient communication methodologies for these devices. By regarding human tissue as communication channel, IBC making use of the conductivities properties of human tissue to send electrical signal from transmitter to receiver. In this paper, the authors proposed a new mathematical model for galvanic coupling type IBC based on a human limb. Starting from the electromagnetic theory, the authors treat human tissue as volume conductor, which is in analogous with the bioelectric phenomena analysis. In order to explain the mechanism of galvanic coupling type technique of IBC, applying the quasi-static approximation, the governing equation can be reduced to Laplace Equation. Finally, the analytical model is evaluated with on-body measurement for testing its performance. The comparison result shows that the developed mathematical model can provide good approximation for galvanic coupling type IBC on human limb under low operating frequencies.

Characterizing the In-Phase Reflection Bandwidth Theoretical Limit of Artificial Magnetic Conductors With a Transmission Line Model

NASA Technical Reports Server (NTRS)

Xie, Yunsong; Fan, Xin; Chen, Yunpeng; Wilson, Jeefrey D.; Simons, Rainee N.; Xiao, John Q.

2013-01-01

We validate through simulation and experiment that artificial magnetic conductors (AMC s) can be well characterized by a transmission line model. The theoretical bandwidth limit of the in-phase reflection can be expressed in terms of the effective RLC parameters from the surface patch and the properties of the substrate. It is found that the existence of effective inductive components will reduce the in-phase reflection bandwidth of the AMC. Furthermore, we propose design strategies to optimize AMC structures with an in-phase reflection bandwidth closer to the theoretical limit.

Geoelectrical structure of the central zone of Piton de la Fournaise volcano (Reunion)

USGS Publications Warehouse

Lenat, J.-F.; Fitterman, D.; Jackson, D.B.; Labazuy, P.

2000-01-01

A study of the geoelectrical structure of the central part of Piton de la Fournaise volcano (Reunion, Indian Ocean) was made using direct current electrical (DC) and transient electromagnetic soundings (TEM). Piton de la Fournaise is a highly active oceanic basaltic shield and has been active for more than half a million years. Joint interpretation of the DC and TEM data allows us to obtain reliable 1D models of the resistivity distribution. The depth of investigation is of the order of 1.5 km but varies with the resistivity pattern encountered at each sounding. Two-dimensional resistivity cross sections were constructed by interpolation between the soundings of the 1D interpreted models. Conductors with resistivities less than 100 ohm-m are present at depth beneath all of the soundings and are located high in the volcanic edifice at elevations between 2000 and 1200 m. The deepest conductor has a resistivity less than 20 ohm-m for soundings located inside the Enclos and less than 60-100 ohm-m for soundings outside the Enclos. From the resistivity distributions, two zones are distinguished: (a) the central zone of the Enclos; and (b) the outer zone beyond the Enclos. Beneath the highly active summit area, the conductor rises to within a few hundred meters of the surface. This bulge coincides with a 2000-mV self-potential anomaly. Low-resistivity zones are inferred to show the presence of a hydrothermal system where alteration by steam and hot water has lowered the resistivity of the rocks. Farther from the summit, but inside the Enclos the depth to the conductive layers increases to approximately 1 km and is inferred to be a deepening of the hydrothermally altered zone. Outside of the Enclos, the nature of the deep, conductive layers is not established. The observed resistivities suggest the presence of hydrated minerals, which could be found in landslide breccias, in hydrothermally altered zones, or in thick pyroclastic layers. Such formations often create perched water tables. The known occurrence of large eastward-moving landslides in the evolution of Piton de la Fournaise strongly suggests that large volumes of breccias should exist in the interior of the volcano; however, extensive breccia deposits are not observed at the bottom of the deep valleys that incise the volcano to elevations lower than those determined for the top of the conductors. The presence of the center of Piton de la Fournaise beneath the Plaine des Sables area during earlier volcanic stages (ca. 0.5 to 0.150 Ma) may have resulted in broad hydrothermal alteration of this zone. However, this interpretation cannot account for the low resistivities in peripheral zones. It is not presently possible to discriminate between these general interpretations. In addition, the nature of the deep conductors may be different in each zone. Whatever the geologic nature of these conductive layers, their presence indicates a major change of lithology at depth, unexpected for a shield volcano such as Piton de la Fournaise.

Induction heaters used to heat subsurface formations

DOEpatents

Nguyen, Scott Vinh [Houston, TX; Bass, Ronald M [Houston, TX

2012-04-24

A heating system for a subsurface formation includes an elongated electrical conductor located in the subsurface formation. The electrical conductor extends between at least a first electrical contact and a second electrical contact. A ferromagnetic conductor at least partially surrounds and at least partially extends lengthwise around the electrical conductor. The electrical conductor, when energized with time-varying electrical current, induces sufficient electrical current flow in the ferromagnetic conductor such that the ferromagnetic conductor resistively heats to a temperature of at least about 300.degree. C.

A Fortran 77 computer code for damped least-squares inversion of Slingram electromagnetic anomalies over thin tabular conductors

NASA Astrophysics Data System (ADS)

Dondurur, Derman; Sarı, Coşkun

2004-07-01

A FORTRAN 77 computer code is presented that permits the inversion of Slingram electromagnetic anomalies to an optimal conductor model. Damped least-squares inversion algorithm is used to estimate the anomalous body parameters, e.g. depth, dip and surface projection point of the target. Iteration progress is controlled by maximum relative error value and iteration continued until a tolerance value was satisfied, while the modification of Marquardt's parameter is controlled by sum of the squared errors value. In order to form the Jacobian matrix, the partial derivatives of theoretical anomaly expression with respect to the parameters being optimised are calculated by numerical differentiation by using first-order forward finite differences. A theoretical and two field anomalies are inserted to test the accuracy and applicability of the present inversion program. Inversion of the field data indicated that depth and the surface projection point parameters of the conductor are estimated correctly, however, considerable discrepancies appeared on the estimated dip angles. It is therefore concluded that the most important factor resulting in the misfit between observed and calculated data is due to the fact that the theory used for computing Slingram anomalies is valid for only thin conductors and this assumption might have caused incorrect dip estimates in the case of wide conductors.

AC loss, interstrand resistance and mechanical properties of prototype EU DEMO TF conductors up to 30 000 load cycles

NASA Astrophysics Data System (ADS)

Yagotintsev, K.; Nijhuis, A.

2018-07-01

Two prototype Nb3Sn cable-in-conduit conductors conductors were designed and manufactured for the toroidal field (TF) magnet system of the envisaged European DEMO fusion reactor. The AC loss, contact resistance and mechanical properties of two sample conductors were tested in the Twente Cryogenic Cable Press under cyclic load up to 30 000 cycles. Though both conductors were designed to operate at 82 kA in a background magnetic field of 13.6 T, they reflect different approaches with respect to the magnet winding pack assembly. The first approach is based on react and wind technology while the second is the more common wind and react technology. Each conductor was tested first for AC loss in virgin condition without handling. The impact of Lorentz load during magnet operation was simulated using the cable press. In the press each conductor specimen was subjected to transverse cyclic load up to 30 000 cycles in liquid helium bath at 4.2 K. Here a summary of results for AC loss, contact resistance, conductor deformation, mechanical heat production and conductor stiffness evolution during cycling of the load is presented. Both conductors showed similar mechanical behaviour but quite different AC loss. In comparison with previously tested ITER TF conductors, both DEMO TF conductors possess very low contact resistance resulting in high coupling loss. At the same time, load cycling has limited impact on properties of DEMO TF conductors in comparison with ITER TF conductors.

Experimentally determined transport and magnetization ac losses of small cable models constructed from YBCO coated conductors

NASA Astrophysics Data System (ADS)

Šouc, J.; Vojenčiak, M.; Gömöry, F.

2010-04-01

Several short cable models were constructed from YBCO coated conductor (YBCO CC) to study their basic dc and ac electrical properties. They were prepared using superconducting tapes helically wound on fiberglass former of different diameter (5, 8 and 10 mm) with different twist pitch (from 1.7 up to 2.4 cm). The number of parallel-connected tapes ranged from 1 up to 6. The standard length of the models was 11 cm. In one case a 35 cm long model has been manufactured in order to perform a bending test. We observed that the critical currents of the models were proportional to the number of tapes used for their construction. Transport and magnetization ac loss were measured at 36 and 72 Hz.

Testing of the 3M Company Composite Conductor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stovall, John P; Rizy, D Tom; Kisner, Roger A

2010-10-01

The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum-Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors. The objective of this work is to accelerate the commercial acceptance by electric utilities of this new conductor design by testing four representative conductor classes in controlled conditions. A unique facility called the Powerline Conductor Accelerated Testing (PCAT) Facility was built at ORNL for testing overhead conductors. The PCAT has been uniquely designed for testing overhead bare transmission line conductors at high currents and temperatures after they have beenmore » installed and tensioned to the manufacturer's specifications. The ability to operate a transmission line conductor in this manner does not exist elsewhere in the United States. Four classes of ACCR cable designed by the 3M Company have been successfully test at ORNL small, medium, large and small/compact. Based on these and other manufacturer tests, the 3M Company has successfully introduced the ACCR into the commercial market and has completed over twenty installations for utility companies.« less

30 CFR Appendix I to Subpart D of... - Appendix I to Subpart D of Part 18

Code of Federal Regulations, 2011 CFR

2011-07-01

... diameter of three-conductor portable power cables with tolerances in inches—601 to 5,000 volts. 8 Fuse... diameters. Table 1—Portable Power Cable Ampacities—600 Volts (Amperes Per Conductor Based on 60 °C. Copper Temperature—40 °C. Ambient) Conductor size—AWG or MCM Single conductor 2-conductor, round or flat 3-conductor...

30 CFR Appendix I to Subpart D of... - Appendix I to Subpart D of Part 18

Code of Federal Regulations, 2010 CFR

2010-07-01

... diameter of three-conductor portable power cables with tolerances in inches—601 to 5,000 volts. 8 Fuse... diameters. Table 1—Portable Power Cable Ampacities—600 Volts (Amperes Per Conductor Based on 60 °C. Copper Temperature—40 °C. Ambient) Conductor size—AWG or MCM Single conductor 2-conductor, round or flat 3-conductor...

Finite element analysis on deformation of stretchable electronic interconnect substrate using polydimethylsiloxanes (PDMS)

NASA Astrophysics Data System (ADS)

Roslan, M. F.; Shaffiar, N. M.; Khairusshima, M. K. N.; Sharifah, I. S. S.

2018-01-01

Over the years, the technology of electronic industry has growth tremendously. Open ended research on how to make a better concept of electronic circuit is ongoing especially on the stretchable electronic devices. There are many designs to achieve stretchability in electronic circuits. The problem occurs when deformation applied to the stretchable electronic circuit, it cannot maintain its functionality. Fracture may happen on the conductor. In this research, the study on deformation of stretchable electronic interconnects substrate using Polydimethlysiloxanes is carried out. The purpose of this research are to study the axial deformation occur, to determine the optimum shape of the conductor designs (horseshoe, rectangular and u-shape design) for the stretchable electronic interconnect and to compare the mechanical properties of Polydimethlysiloxanes (PDMS) with Polyurethane (PU) using Finite Element Analysis (FEA). The simulation was done on the FE model of the stretchable circuit with dimension of 2.4 X 2.4 X 0.5 mm. The stretching of the FE model was simulated with the range of elongation at 10, 20 and 30 percent from its original length in order to find the strain value for all three of the conductor designs. The best conductor design is used to simulate with different types of substrate (PDMS and PU). From the simulation result, Horseshoe design record the lowest strain value for each elongation, followed by rectangular and U-shape design. Thus, Horseshoe is considered as the optimum design for the conductor compared to the other two designs. From the result also, it shows that PDMS substrate will offer more maximum allowable stretchability compared to PU substrates. Thus PDMS is considered as a better substrate compare to PU. PDMS is a good material to replace PU since it can perform under tension much better mechanically.

Metallographic autopsies of full-scale ITER prototype cable-in-conduit conductors after full cyclic testing in SULTAN: III. The importance of strand surface roughness in long twist pitch conductors

DOE PAGES

Sanabria, Charlie; Lee, Peter J.; Starch, William; ...

2016-05-31

As part of the ITER conductor qualification process, 3 m long Cable-in-Conduit Conductors (CICCs) were tested at the SULTAN facility under conditions simulating ITER operation so as to establish the current sharing temperature, T cs, as a function of multiple full Lorentz force loading cycles. After a comprehensive evaluation of both the Toroidal Field (TF) and the Central Solenoid (CS) conductors, it was found that T cs degradation was common in long twist pitch TF conductors while short twist pitch CS conductors showed some T cs increase. However, one kind of TF conductors containing superconducting strand fabricated by the Bochvarmore » Institute of Inorganic Materials (VNIINM) avoided T cs degradation despite having long twist pitch. In our earlier metallographic autopsies of long and short twist pitch CS conductors, we observed a substantially greater transverse strand movement under Lorentz force loading for long twist pitch conductors, while short twist pitch conductors had negligible transverse movement. With help from the literature, we concluded that the transverse movement was not the source of T cs degradation but rather an increase of the compressive strain in the Nb 3Sn filaments possibly induced by longitudinal movement of the wires. Like all TF conductors this TF VNIINM conductor showed large transverse motions under Lorentz force loading, but Tcs actually increased, as in all short twist pitch CS conductors. We here propose that the high surface roughness of the VNIINM strand may be responsible for the suppression of the compressive strain enhancement (characteristic of long twist pitch conductors). Furthermore, it appears that increasing strand surface roughness could improve the performance of long twist pitch CICCs.« less

Metallographic autopsies of full-scale ITER prototype cable-in-conduit conductors after full cyclic testing in SULTAN: III. The importance of strand surface roughness in long twist pitch conductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanabria, Charlie; Lee, Peter J.; Starch, William

As part of the ITER conductor qualification process, 3 m long Cable-in-Conduit Conductors (CICCs) were tested at the SULTAN facility under conditions simulating ITER operation so as to establish the current sharing temperature, T cs, as a function of multiple full Lorentz force loading cycles. After a comprehensive evaluation of both the Toroidal Field (TF) and the Central Solenoid (CS) conductors, it was found that T cs degradation was common in long twist pitch TF conductors while short twist pitch CS conductors showed some T cs increase. However, one kind of TF conductors containing superconducting strand fabricated by the Bochvarmore » Institute of Inorganic Materials (VNIINM) avoided T cs degradation despite having long twist pitch. In our earlier metallographic autopsies of long and short twist pitch CS conductors, we observed a substantially greater transverse strand movement under Lorentz force loading for long twist pitch conductors, while short twist pitch conductors had negligible transverse movement. With help from the literature, we concluded that the transverse movement was not the source of T cs degradation but rather an increase of the compressive strain in the Nb 3Sn filaments possibly induced by longitudinal movement of the wires. Like all TF conductors this TF VNIINM conductor showed large transverse motions under Lorentz force loading, but Tcs actually increased, as in all short twist pitch CS conductors. We here propose that the high surface roughness of the VNIINM strand may be responsible for the suppression of the compressive strain enhancement (characteristic of long twist pitch conductors). Furthermore, it appears that increasing strand surface roughness could improve the performance of long twist pitch CICCs.« less

Design of a Wireless Sensor Module for Monitoring Conductor Galloping of Transmission Lines.

PubMed

Huang, Xinbo; Zhao, Long; Chen, Guimin

2016-10-09

Conductor galloping may cause flashovers and even tower collapses. The available conductor galloping monitoring methods often employ acceleration sensors to measure the conductor translations without considering the conductor twist. In this paper, a new sensor for monitoring conductor galloping of transmission lines based on an inertial measurement unit and wireless communication is proposed. An inertial measurement unit is used for collecting the accelerations and angular rates of a conductor, which are further transformed into the corresponding geographic coordinate frame using a quaternion transformation to reconstruct the galloping of the conductor. Both the hardware design and the software design are described in details. The corresponding test platforms are established, and the experiments show the feasibility and accuracy of the proposed monitoring sensor. The field operation of the proposed sensor in a conductor spanning 734 m also shows its effectiveness.

30 CFR 57.12011 - High-potential electrical conductors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-potential electrical conductors. 57.12011... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential electrical conductors shall be covered, insulated, or placed to prevent contact with low potential conductors. ...

33 CFR 183.445 - Conductors: Protection.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Conductors: Protection. 183.445 Section 183.445 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Conductors: Protection. (a) Each conductor or group of conductors that passes through a bulkhead, structural...

33 CFR 183.445 - Conductors: Protection.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Conductors: Protection. 183.445 Section 183.445 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Conductors: Protection. (a) Each conductor or group of conductors that passes through a bulkhead, structural...

33 CFR 159.71 - Electrical controls and conductors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conductors. 159.71 Section 159.71 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors must...

30 CFR 57.12004 - Electrical conductors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical conductors. 57.12004 Section 57... Surface and Underground § 57.12004 Electrical conductors. Electrical conductors shall be of a sufficient... operations will not damage the insulating materials. Electrical conductors exposed to mechanical damage shall...

33 CFR 159.71 - Electrical controls and conductors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conductors. 159.71 Section 159.71 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors must...

30 CFR 57.12011 - High-potential electrical conductors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-potential electrical conductors. 57.12011... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential electrical conductors shall be covered, insulated, or placed to prevent contact with low potential conductors. ...

30 CFR 57.12004 - Electrical conductors.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical conductors. 57.12004 Section 57... Surface and Underground § 57.12004 Electrical conductors. Electrical conductors shall be of a sufficient... operations will not damage the insulating materials. Electrical conductors exposed to mechanical damage shall...

30 CFR 57.12004 - Electrical conductors.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical conductors. 57.12004 Section 57... Surface and Underground § 57.12004 Electrical conductors. Electrical conductors shall be of a sufficient... operations will not damage the insulating materials. Electrical conductors exposed to mechanical damage shall...

Design, development, fabrication and testing of high temperature Flat Conductor Cable (FCC)

NASA Technical Reports Server (NTRS)

Rigling, W. S.

1974-01-01

The results are presented of a development program for a flat, 25-conductor signal cable and a flat, 3-conductor power cable. Flat cables employ conductors made of strips or flattened round copper conductors insulated with polyimide films. It is shown that conductor thickness ranges from 0.003 to 0.010 inch, and begins to soften and loose mechanical strength at temperatures above 200 C.

Application of the parametric proper generalized decomposition to the frequency-dependent calculation of the impedance of an AC line with rectangular conductors

NASA Astrophysics Data System (ADS)

Sancarlos-González, Abel; Pineda-Sanchez, Manuel; Puche-Panadero, Ruben; Sapena-Bano, Angel; Riera-Guasp, Martin; Martinez-Roman, Javier; Perez-Cruz, Juan; Roger-Folch, Jose

2017-12-01

AC lines of industrial busbar systems are usually built using conductors with rectangular cross sections, where each phase can have several parallel conductors to carry high currents. The current density in a rectangular conductor, under sinusoidal conditions, is not uniform. It depends on the frequency, on the conductor shape, and on the distance between conductors, due to the skin effect and to proximity effects. Contrary to circular conductors, there are not closed analytical formulas for obtaining the frequency-dependent impedance of conductors with rectangular cross-section. It is necessary to resort to numerical simulations to obtain the resistance and the inductance of the phases, one for each desired frequency and also for each distance between the phases' conductors. On the contrary, the use of the parametric proper generalized decomposition (PGD) allows to obtain the frequency-dependent impedance of an AC line for a wide range of frequencies and distances between the phases' conductors by solving a single simulation in a 4D domain (spatial coordinates x and y, the frequency and the separation between conductors). In this way, a general "virtual chart" solution is obtained, which contains the solution for any frequency and for any separation of the conductors, and stores it in a compact separated representations form, which can be easily embedded on a more general software for the design of electrical installations. The approach presented in this work for rectangular conductors can be easily extended to conductors with an arbitrary shape.

A new kind of low-inductance transformer type magnetic switch (TTMS) with coaxial cylindrical conductors

NASA Astrophysics Data System (ADS)

Zhang, Yu; Liu, Jinliang

2013-02-01

As important devices for voltage boosting and switching, respectively, pulse transformer and magnetic switch are widely used in pulsed power technology. In this paper, a new kind of transformer type magnetic switch (TTMS) with coaxial cylindrical conductors is put forward to combine the functions of voltage boosting and switching in one power device. As a compact combination device of discrete pulse transformer and magnetic switch, the compact TTMS decreases the required volume of magnetic cores in a large scale. The primary windings of the TTMS have a parallel combination structure so that the TTMS which only has 3 turns of secondary windings has a step-up ratio at 1:9. Before the magnetic core saturates, the TTMS has low unsaturated inductances of windings and good pulse response characteristics, so it can be used to substitute the Marx generator to charge the pulse forming line (PFL) at the ranges of several hundred kV and several hundred ns. After the core saturates, the cylindrical conductors can decrease the saturated inductance of the secondary windings of TTMS to a level less than 400 nH. As a result, the proposed TTMS can be used as the boosting transformer and main switch of helical Blumlein PFL to form the quasi-square voltage pulse on the 160 Ω load with a short pulse rise time only at 60 ns.

A new kind of low-inductance transformer type magnetic switch (TTMS) with coaxial cylindrical conductors.

PubMed

Zhang, Yu; Liu, Jinliang

2013-02-01

As important devices for voltage boosting and switching, respectively, pulse transformer and magnetic switch are widely used in pulsed power technology. In this paper, a new kind of transformer type magnetic switch (TTMS) with coaxial cylindrical conductors is put forward to combine the functions of voltage boosting and switching in one power device. As a compact combination device of discrete pulse transformer and magnetic switch, the compact TTMS decreases the required volume of magnetic cores in a large scale. The primary windings of the TTMS have a parallel combination structure so that the TTMS which only has 3 turns of secondary windings has a step-up ratio at 1:9. Before the magnetic core saturates, the TTMS has low unsaturated inductances of windings and good pulse response characteristics, so it can be used to substitute the Marx generator to charge the pulse forming line (PFL) at the ranges of several hundred kV and several hundred ns. After the core saturates, the cylindrical conductors can decrease the saturated inductance of the secondary windings of TTMS to a level less than 400 nH. As a result, the proposed TTMS can be used as the boosting transformer and main switch of helical Blumlein PFL to form the quasi-square voltage pulse on the 160 Ω load with a short pulse rise time only at 60 ns.

24 CFR 3280.815 - Polarization.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) The identified (white) conductor shall be employed for grounding circuit conductors only and shall be... unswitched wire in switched circuits, except that a cable containing an identified conductor (white) shall be... unidentified conductor is the return conductor from the switch to the outlet. Painting of the terminal end of...

46 CFR 169.683 - Overcurrent protection, general.

Code of Federal Regulations, 2011 CFR

2011-10-01

... provided for each ungrounded conductor for the purpose of opening the electric circuit if the current reaches a value that causes an excessive or dangerous temperature in the conductor or conductor insulation... ungrounded conductors of the circuit simultaneously. (c) Each conductor, including a generator lead and shore...

24 CFR 3280.815 - Polarization.

Code of Federal Regulations, 2011 CFR

2011-04-01

...) The identified (white) conductor shall be employed for grounding circuit conductors only and shall be... unswitched wire in switched circuits, except that a cable containing an identified conductor (white) shall be... unidentified conductor is the return conductor from the switch to the outlet. Painting of the terminal end of...

Numerical Modeling of Saturated Boiling in a Heated Tube

NASA Technical Reports Server (NTRS)

Majumdar, Alok; LeClair, Andre; Hartwig, Jason

2017-01-01

This paper describes a mathematical formulation and numerical solution of boiling in a heated tube. The mathematical formulation involves a discretization of the tube into a flow network consisting of fluid nodes and branches and a thermal network consisting of solid nodes and conductors. In the fluid network, the mass, momentum and energy conservation equations are solved and in the thermal network, the energy conservation equation of solids is solved. A pressure-based, finite-volume formulation has been used to solve the equations in the fluid network. The system of equations is solved by a hybrid numerical scheme which solves the mass and momentum conservation equations by a simultaneous Newton-Raphson method and the energy conservation equation by a successive substitution method. The fluid network and thermal network are coupled through heat transfer between the solid and fluid nodes which is computed by Chen's correlation of saturated boiling heat transfer. The computer model is developed using the Generalized Fluid System Simulation Program and the numerical predictions are compared with test data.

Preliminary fabrication and characterization of low-leakage hybrid coaxial cable

NASA Astrophysics Data System (ADS)

Rudnitsky, Arkady; Elbaz, David; Zalevsky, Zeev

2013-10-01

In this paper we present the fabrication and the initial characterization of a new type of coaxial cable having reduced leakage characteristics and the capability of transmitting optical signals, in additional to the RF signal, through the glass medium between the metallic conductors. The suggested decreased leakage and material loss is obtained by using different metallic shield geometry. The suggested model is composed of a central conductor surrounded by plurality of metallic wires circularly disposed.

Self-consistent modelling of electrochemical strain microscopy in mixed ionic-electronic conductors: Nonlinear and dynamic regimes

DOE PAGES

Varenyk, O. V.; Silibin, M. V.; Kiselev, Dmitri A.; ...

2015-08-19

The frequency dependent Electrochemical Strain Microscopy (ESM) response of mixed ionic-electronic conductors is analyzed within the framework of Fermi-Dirac statistics and the Vegard law, accounting for steric effects from mobile donors. The emergence of dynamic charge waves and nonlinear deformation of the surface in response to bias applied to the tip-surface junction is numerically explored. The 2D maps of the strain and concentration distributions across the mixed ionic-electronic conductor and bias-induced surface displacements are calculated. Furthermore, the obtained numerical results can be applied to quantify the ESM response of Li-based solid electrolytes, materials with resistive switching, and electroactive ferroelectric polymers,more » which are of potential interest for flexible and high-density non-volatile memory devices.« less

Self-consistent modelling of electrochemical strain microscopy in mixed ionic-electronic conductors: Nonlinear and dynamic regimes

NASA Astrophysics Data System (ADS)

Varenyk, O. V.; Silibin, M. V.; Kiselev, D. A.; Eliseev, E. A.; Kalinin, S. V.; Morozovska, A. N.

2015-08-01

The frequency dependent Electrochemical Strain Microscopy (ESM) response of mixed ionic-electronic conductors is analyzed within the framework of Fermi-Dirac statistics and the Vegard law, accounting for steric effects from mobile donors. The emergence of dynamic charge waves and nonlinear deformation of the surface in response to bias applied to the tip-surface junction is numerically explored. The 2D maps of the strain and concentration distributions across the mixed ionic-electronic conductor and bias-induced surface displacements are calculated. The obtained numerical results can be applied to quantify the ESM response of Li-based solid electrolytes, materials with resistive switching, and electroactive ferroelectric polymers, which are of potential interest for flexible and high-density non-volatile memory devices.

30 CFR 56.12005 - Protection of power conductors from mobile equipment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Protection of power conductors from mobile... MINES Electricity § 56.12005 Protection of power conductors from mobile equipment. Mobile equipment shall not run over power conductors, nor shall loads be dragged over power conductors, unless the...

An Exploratory Comparison of Novice, Intermediate, and Expert Orchestral Conductors

ERIC Educational Resources Information Center

Bergee, Martin J.

2005-01-01

This study compared novice, "intermediate" (graduate student), and expert orchestral conductors. Two novice conductors, one graduate student in orchestral conducting, and one expert conductor led a university symphony orchestra in part of the first movement of Brahms's Symphony No. 2. Wired for sound, conductors attempted to verbalize their…

30 CFR 56.12005 - Protection of power conductors from mobile equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection of power conductors from mobile... MINES Electricity § 56.12005 Protection of power conductors from mobile equipment. Mobile equipment shall not run over power conductors, nor shall loads be dragged over power conductors, unless the...

Electro-expulsive separation system

NASA Technical Reports Server (NTRS)

Haslim, Leonard A. (Inventor); Lee, Robert D. (Inventor)

1987-01-01

An electro-expulsive system has one or more overlapped conductors, each comprising a flexible ribbon conductor, which is folded back on itself. The conductors are embedded in an elastomeric material. Large current pulses are fed to the conductors from power storage units. As a result of the antiparallel currents, the opposed segments of a conductor are forcefully separated and the elastomeric material is distended. Voids in the elastomer aid the separation of the conductor segments. The distention is almost instantaneous when a current pulse reaches the conductor and the distention tends to remove any solid body on the surface of the elastomeric material.

Multifilamentary niobium tin magnet conductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Larbalestier, D.C.; Madsen, P.E.; Lee, J.A.

1975-03-01

Practical magnet conductors of multifilamentary Nb$sub 3$Sn have been produced. Evaluation of these bronze route conductors is described. Conductors studied range from a 1369 filament all-bronze matrix conductor to 5143 and approximately 42,000 filament conductors, containing internal high purity copper protected by diffusion barriers. Filament sizes vary from approximately 3 to 8 $mu$m diameter. The effect of heat treatment conditions on critical current and transition temperature is presented and it is shown that overall critical current densities greater than those available in niobium titanium can now be produced in multifilamentary Nb$sub 3$Sn magnet conductor.

Diamagnetic composite material structure for reducing undesired electromagnetic interference and eddy currents in dielectric wall accelerators and other devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caporaso, George J.; Poole, Brian R.; Hawkins, Steven A.

2015-06-30

The devices, systems and techniques disclosed here can be used to reduce undesired effects by magnetic field induced eddy currents based on a diamagnetic composite material structure including diamagnetic composite sheets that are separated from one another to provide a high impedance composite material structure. In some implementations, each diamagnetic composite sheet includes patterned conductor layers are separated by a dielectric material and each patterned conductor layer includes voids and conductor areas. The voids in the patterned conductor layers of each diamagnetic composite sheet are arranged to be displaced in position from one patterned conductor layer to an adjacent patternedmore » conductor layer while conductor areas of the patterned conductor layers collectively form a contiguous conductor structure in each diamagnetic composite sheet to prevent penetration by a magnetic field.« less

Coupling time constants of striated and copper-plated coated conductors and the potential of striation to reduce shielding-current-induced fields in pancake coils

NASA Astrophysics Data System (ADS)

Amemiya, Naoyuki; Tominaga, Naoki; Toyomoto, Ryuki; Nishimoto, Takuma; Sogabe, Yusuke; Yamano, Satoshi; Sakamoto, Hisaki

2018-07-01

The shielding-current-induced field is a serious concern for the applications of coated conductors to magnets. The striation of the coated conductor is one of the countermeasures, but it is effective only after the decay of the coupling current, which is characterised with the coupling time constant. In a non-twisted striated coated conductor, the coupling time constant is determined primarily by its length and the transverse resistance between superconductor filaments, because the coupling current could flow along its entire length. We measured and numerically calculated the frequency dependences of magnetisation losses in striated and copper-plated coated conductors with various lengths and their stacks at 77 K and determined their coupling time constants. Stacked conductors simulate the turns of a conductor wound into a pancake coil. Coupling time constants are proportional to the square of the conductor length. Stacking striated coated conductors increases the coupling time constants because the coupling currents in stacked conductors are coupled to one another magnetically to increase the mutual inductances for the coupling current paths. We carried out the numerical electromagnetic field analysis of conductors wound into pancake coils and determined their coupling time constants. They can be explained by the length dependence and mutual coupling effect observed in stacked straight conductors. Even in pancake coils with practical numbers of turns, i.e. conductor lengths, the striation is effective to reduce the shielding-current-induced fields for some dc applications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stovall, J.P.; RIzy, D.T.; Kisner, R.A.

The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum- Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors so the core has a lower density and higher conductivity. The objective of this work is to accelerate the commercial acceptance by electric utilities of these new conductor designs by testing four representative conductor classes in controlled conditions. Overhead transmission lines use bare aluminum conductor strands wrapped around a steel core strands to transmit electricity. The typical cable is referred to as aluminum-conductor steel-reinforced (ACSR). The outer strandsmore » are aluminum, chosen for its conductivity, low weight, and low cost. The center strand is of steel for the strength required to support the weight without stretching the aluminum due to its ductility. The power density of a transmission corridor has been directly increased by increasing the voltage level. Transmission voltages have increased from 115-kV to 765- kV over the past 80 years. In the United States, further increasing the voltage level is not feasible at this point in time, so in order to further increase the power density of a transmission corridor, conductor designs that increase the current carrying capability have been examined. One of the key limiting factors in the design of a transmission line is the conductor sag which determines the clearance of the conductor above ground or underlying structures needed for electrical safety. Increasing the current carrying capability of a conductor increases the joule heating in the conductor which increases the conductor sag. A conductor designed for high-temperature and lowsag operation requires an engineered modification of the conductor materials. To make an advanced cable, the 3M Company solution has been the development of a composite conductor consisting of Nextel ceramic fibers to replace the steel core and an aluminum-zirconium alloy to improve the outer strands. The result is a cable that can carry more current than steelaluminum lines without sagging as much at higher temperatures. A unique facility called the Powerline Conductor Accelerated Testing (PCAT) Facility was built at ORNL for testing overhead conductors. The PCAT has been uniquely designed for testing overhead bare transmission line conductors at high currents and temperatures after they have been installed and tensioned to the manufacturer's specifications. The ability to operate a transmission line conductor in this manner does not exist elsewhere in the United States. Four classes of ACCR cable designed by 3M have been successfully test at ORNL – small, medium, large and small/compact. Based on these and other manufacturer tests, the 3M Company has successfully introduced the ACCR into the commercial market and has completed over twenty installations for utility companies.« less

Materials Requirements for Advanced Energy Systems - New Fuels. Volume 3: Materials Research Needs in Advanced Energy Systems Using New Fuels

DTIC Science & Technology

1974-07-01

elec- Materials se: trode materials and associ- operational ated conductors. 2.5.1 General. H" (02) Materials resources Technoeconomic analysis - None...Advanced Energy Systems Using New Fnels VIII Correlation and Analysis of Materials Requirements IX Research Recommendations and Priorities The authois...of government and industrial organizal ions who gave us the benefit of their knowledge and experience. iv VIII CORRELATION ANU ANALYSIS OF MATERIALS

30 CFR 57.12080 - Bare conductor guards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at... conductors are less than 7 feet above the rail, they shall be guarded at all points where persons work or...

30 CFR 77.804 - High-voltage trailing cables; minimum design requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... equipped with metallic shields around each power conductor with one or more ground conductors having a total cross-sectional area of not less than one-half the power conductor, and with an insulated conductor for the ground continuity check circuit. External ground check conductors may be used if they are...

30 CFR 57.12080 - Bare conductor guards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at... conductors are less than 7 feet above the rail, they shall be guarded at all points where persons work or...

Conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

DOEpatents

Fischer, William H.; Yoon, Kue H.

1984-04-10

A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed perpendicular to the direction of travel of the inner conductor/insulating support assembly.

Nanoscale electromechanical parametric amplifier

DOEpatents

Aleman, Benjamin Jose; Zettl, Alexander

2016-09-20

This disclosure provides systems, methods, and apparatus related to a parametric amplifier. In one aspect, a device includes an electron source electrode, a counter electrode, and a pumping electrode. The electron source electrode may include a conductive base and a flexible conductor. The flexible conductor may have a first end and a second end, with the second end of the flexible conductor being coupled to the conductive base. A cross-sectional dimension of the flexible conductor may be less than about 100 nanometers. The counter electrode may be disposed proximate the first end of the flexible conductor and spaced a first distance from the first end of the flexible conductor. The pumping electrode may be disposed proximate a length of the flexible conductor and spaced a second distance from the flexible conductor.

Wireless tamper detection sensor and sensing system

NASA Technical Reports Server (NTRS)

Woodard, Stanley E. (Inventor); Taylor, Bryant D. (Inventor)

2011-01-01

A wireless tamper detection sensor is defined by a perforated electrical conductor. The conductor is shaped to form a geometric pattern between first and second ends thereof such that the conductor defines an open-circuit that can store and transfer electrical and magnetic energy. The conductor resonates in the presence of a time-varying magnetic field to generate a harmonic response. The harmonic response changes when the conductor experiences a change in its geometric pattern due to severing of the conductor along at least a portion of the perforations. A magnetic field response recorder is used to wirelessly transmit the time-varying magnetic field and wirelessly detecting the conductor's harmonic response.

Plasma Generator Using Spiral Conductors

NASA Technical Reports Server (NTRS)

Szatkowski, George N. (Inventor); Dudley, Kenneth L. (Inventor); Ticatch, Larry A. (Inventor); Smith, Laura J. (Inventor); Koppen, Sandra V. (Inventor); Nguyen, Truong X. (Inventor); Ely, Jay J. (Inventor)

2016-01-01

A plasma generator includes a pair of identical spiraled electrical conductors separated by dielectric material. Both spiraled conductors have inductance and capacitance wherein, in the presence of a time-varying electromagnetic field, the spiraled conductors resonate to generate a harmonic electromagnetic field response. The spiraled conductors lie in parallel planes and partially overlap one another in a direction perpendicular to the parallel planes. The geometric centers of the spiraled conductors define endpoints of a line that is non-perpendicular with respect to the parallel planes. A voltage source coupled across the spiraled conductors applies a voltage sufficient to generate a plasma in at least a portion of the dielectric material.

Modification of the Mathematical Model of the Thermoelectric Module of a Thermostating Coating

NASA Astrophysics Data System (ADS)

Zarubin, V. S.; Kuvyrkin, G. N.; Savel'eva, I. Yu.

2017-03-01

A modification has been made of the previously constructed mathematical model of a fragment of a flat thermostating coating including a thermoelectric module based on the variation formulation of the stationary problem of heat conduction in an inhomogeneous solid body. With the use of the Fourier finite integral transform the dependences have been obtained for calculating the temperature distribution in the heat insulating layer in the vicinity of the thermoelectric element and commutating conductors. This enabled us to refine one of the diagnostic variables of the model — the total heat resistance of the heat insulator between commutating plates and conductors of the thermoelectric module influencing the energy characteristics of the thermostating coating under investigation.

46 CFR 111.60-4 - Minimum cable conductor size.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...

46 CFR 111.60-4 - Minimum cable conductor size.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...

Comparison of ATLOG and Xyce for Bell Labs Electromagnetic Pulse Excitation of Finite-Long Dissipative Conductors over a Ground Plane.

DOE Office of Scientific and Technical Information (OSTI.GOV)

campione, Salvatore; Warne, Larry K.; Schiek, Richard

This report details the modeling results for the response of a finite-length dissipative conductor interacting with a conducting ground to the Bell Labs electromagnetic pulse excitation. We use both a frequency-domain and a time-domain method based on transmission line theory through a code we call ATLOG - Analytic Transmission Line Over Ground. Results are compared to the circuit simulator Xyce for selected cases. Intentionally Left Blank

Electromagnetic Pulse Excitation of Finite-Long Dissipative Conductors over a Conducting Ground Plane in the Frequency Domain.

DOE Office of Scientific and Technical Information (OSTI.GOV)

campione, Salvatore; Warne, Larry K.; Schiek, Richard

2017-09-01

This report details the modeling results for the response of a finite-length dissipative conductor interacting with a conducting ground to a hypothetical nuclear device with the same output energy spectrum as the Fat Man device. We use a frequency-domain method based on transmission line theory and implemented it in a code we call ATLOG - Analytic Transmission Line Over Ground. Select results are compared to ones computed using the circuit simulator Xyce. Intentionally Left Blank

Wiring assembly and method of forming a channel in a wiring assembly for receiving conductor and providing separate regions of conductor contact with the channel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stelzer, Gerald; Meinke, Rainer; Senti, Mark

A conductor assembly and method for constructing an assembly of the type which, when conducting current, generates a magnetic field or which, in the presence of a changing magnetic field, induces a voltage. In one embodiment the method provides a first insulative layer tubular in shape and including a surface along which a conductor segment may be positioned. A channel formed in the surface of the insulative layer defines a first conductor path and includes a surface of first contour in cross section along a first plane transverse to the conductor path. A segment of conductor having a surface ofmore » second contour in cross section is positioned at least partly in the channel and extends along the conductor path. Along the first plane, contact between the conductor surface of second contour and the channel surface of first contour includes at least two separate regions of contact.« less

System providing limit switch function with simultaneous absolute position output

NASA Technical Reports Server (NTRS)

Alhorn, Dean C. (Inventor); Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

2006-01-01

A limit and position sensing system includes a sensor assembly and an emitter. The sensor assembly includes first and second electrical conductors arranged in opposing parallel planes. The first electrical conductor is coiled outwardly from either end thereof in a clockwise fashion to form a first coil region and a second coil region. The second electrical conductor forms a single coil with portions of the single coil's rings lying between the first end and second end of the first electrical conductor being parallel to an axis of the first electrical conductor's plane. Ferromagnetic material is aligned with the first and second electrical conductors and spans beyond (a) the first and second ends of the first electrical conductor, and (b) the portions of the rings of the second electrical conductor's single coil that lie between the first end and second end of the first electrical conductor. The emitter is spaced apart from the sensor assembly and transmits a periodic electromagnetic wave towards the sensor assembly.

Bipolar pulse forming line

DOEpatents

Rhodes, Mark A.

2008-10-21

A bipolar pulse forming transmission line module for linear induction accelerators having first, second, third, fourth, and fifth planar conductors which form an interleaved stack with dielectric layers between the conductors. Each conductor has a first end, and a second end adjacent an acceleration axis. The first and second planar conductors are connected to each other at the second ends, the fourth and fifth planar conductors are connected to each other at the second ends, and the first and fifth planar conductors are connected to each other at the first ends via a shorting plate adjacent the first ends. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short a high voltage from the first end of the third planar conductor to the first end of the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

Transverse tripolar stimulation of peripheral nerve: a modelling study of spatial selectivity.

PubMed

Deurloo, K E; Holsheimer, J; Boom, H B

1998-01-01

Various anode-cathode configurations in a nerve cuff are modelled to predict their spatial selectivity characteristics for functional nerve stimulation. A 3D volume conductor model of a monofascicular nerve is used for the computation of stimulation-induced field potentials, whereas a cable model of myelinated nerve fibre is used for the calculation of the excitation thresholds of fibres. As well as the usual configurations (monopole, bipole, longitudinal tripole, 'steering' anode), a transverse tripolar configuration (central cathode) is examined. It is found that the transverse tripole is the only configuration giving convex recruitment contours and therefore maximises activation selectivity for a small (cylindrical) bundle of fibres in the periphery of a monofascicular nerve trunk. As the electrode configuration is changed to achieve greater selectivity, the threshold current increases. Therefore threshold currents for fibre excitation with a transverse tripole are relatively high. Inverse recruitment is less extreme than for the other configurations. The influences of several geometrical parameters and model conductivities of the transverse tripole on selectivity and threshold current are analysed. In chronic implantation, when electrodes are encapsulated by a layer of fibrous tissue, threshold currents are low, whereas the shape of the recruitment contours in transverse tripolar stimulation does not change.

Push-pull radio frequency circuit with integral transistion to waveguide output

DOEpatents

Bennett, Wilfred P.

1987-01-01

A radio frequency circuit for ICRF heating includes a resonant push-pull circuit, a double ridged rectangular waveguide, and a coupling transition which joins the waveguide to the resonant circuit. The resonant circuit includes two cylindrical conductors mounted side by side and two power vacuum tubes attached to respective ends of a cylindrical conductor. A conductive yoke is located at the other end of the cylindrical conductors to short circuit the two cylindrical conductors. The coupling transition includes two relatively flat rectangular conductors extending perpendicular to the longitudinal axes of a respective cylindrical conductor to which the flat conductor is attached intermediate the ends thereof. Conductive side covers and end covers are also provided for forming pockets in the waveguide into which the flat conductors extend when the waveguide is attached to a shielding enclosure surrounding the resonant circuit.

33 CFR 183.435 - Conductors in circuits of 50 volts or more.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Conductors in circuits of 50... Requirements § 183.435 Conductors in circuits of 50 volts or more. (a) Each conductor in a circuit that has a... nominal circuit voltage of each of three or more current carrying conductors in a duct, bundle, or cable...

33 CFR 183.435 - Conductors in circuits of 50 volts or more.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Conductors in circuits of 50... Requirements § 183.435 Conductors in circuits of 50 volts or more. (a) Each conductor in a circuit that has a... nominal circuit voltage of each of three or more current carrying conductors in a duct, bundle, or cable...

33 CFR 183.435 - Conductors in circuits of 50 volts or more.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Conductors in circuits of 50... Requirements § 183.435 Conductors in circuits of 50 volts or more. (a) Each conductor in a circuit that has a... nominal circuit voltage of each of three or more current carrying conductors in a duct, bundle, or cable...

33 CFR 183.435 - Conductors in circuits of 50 volts or more.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Conductors in circuits of 50... Requirements § 183.435 Conductors in circuits of 50 volts or more. (a) Each conductor in a circuit that has a... nominal circuit voltage of each of three or more current carrying conductors in a duct, bundle, or cable...

33 CFR 183.435 - Conductors in circuits of 50 volts or more.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Conductors in circuits of 50... Requirements § 183.435 Conductors in circuits of 50 volts or more. (a) Each conductor in a circuit that has a... nominal circuit voltage of each of three or more current carrying conductors in a duct, bundle, or cable...

Non-binding conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

DOEpatents

Fischer, William H.

1984-01-01

A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a non-binding transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement and for moving without binding along corrugations of any slope less than vertical. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed parallel to the motion of travel of the inner conductor/insulating support assembly.

Electric generator

DOEpatents

Foster, Jr., John S.; Wilson, James R.; McDonald, Jr., Charles A.

1983-01-01

1. In an electrical energy generator, the combination comprising a first elongated annular electrical current conductor having at least one bare surface extending longitudinally and facing radially inwards therein, a second elongated annular electrical current conductor disposed coaxially within said first conductor and having an outer bare surface area extending longitudinally and facing said bare surface of said first conductor, the contiguous coaxial areas of said first and second conductors defining an inductive element, means for applying an electrical current to at least one of said conductors for generating a magnetic field encompassing said inductive element, and explosive charge means disposed concentrically with respect to said conductors including at least the area of said inductive element, said explosive charge means including means disposed to initiate an explosive wave front in said explosive advancing longitudinally along said inductive element, said wave front being effective to progressively deform at least one of said conductors to bring said bare surfaces thereof into electrically conductive contact to progressively reduce the inductance of the inductive element defined by said conductors and transferring explosive energy to said magnetic field effective to generate an electrical potential between undeformed portions of said conductors ahead of said explosive wave front.

Keeping an eye on the conductor: neural correlates of visuo-motor synchronization and musical experience.

PubMed

Ono, Kentaro; Nakamura, Akinori; Maess, Burkhard

2015-01-01

For orchestra musicians, synchronized playing under a conductor's direction is necessary to achieve optimal performance. Previous studies using simple auditory/visual stimuli have reported cortico-subcortical networks underlying synchronization and that training improves the accuracy of synchronization. However, it is unclear whether people who played regularly under a conductor and non-musicians activate the same networks when synchronizing with a conductor's gestures. We conducted a functional magnetic resonance imaging (fMRI) experiment testing nonmusicians and musicians who regularly play music under a conductor. Participants were required to tap the rhythm they perceived from silent movies displaying either conductor's gestures or a swinging metronome. Musicians performed tapping under a conductor with more precision than nonmusicians. Results from fMRI measurement showed greater activity in the anterior part of the left superior frontal gyrus (SFG) in musicians with more frequent practice under a conductor. Conversely, tapping with the metronome did not show any difference between musicians and nonmusicians, indicating that the expertize effect in tapping under the conductor does not result in a general increase in tapping performance for musicians. These results suggest that orchestra musicians have developed an advanced ability to predict conductor's next action from the gestures.

PIC code modeling of spacecraft charging potential during electron beam injection into a background of neutral gas and plasma, part 1

NASA Technical Reports Server (NTRS)

Koga, J. K.; Lin, C. S.; Winglee, R. M.

1989-01-01

Injections of nonrelativistic electron beams from an isolated equipotential conductor into a uniform background of plasma and neutral gas were simulated using a 2-D electrostatic particle code. The ionization effects on spacecraft charging are examined by including interactions of electrons with neutral gas. The simulations show that the conductor charging potential decreases with increasing neutral background density due to the production of secondary electrons near the conductor surface. In the spacecraft wake, the background electrons accelerated towards the charged spacecraft produce an enhancement of secondary electrons and ions. Simulations run for longer times indicate that the spacecraft potential is further reduced and short wavelength beam-plasma oscillations appear. The results are applied to explain the spacecraft charging potential measured during the SEPAC experiments from Spacelab 1.

Electric/magnetic field sensor

DOEpatents

Schill, Jr., Robert A.; Popek, Marc [Las Vegas, NV

2009-01-27

A UNLV novel electric/magnetic dot sensor includes a loop of conductor having two ends to the loop, a first end and a second end; the first end of the conductor seamlessly secured to a first conductor within a first sheath; the second end of the conductor seamlessly secured to a second conductor within a second sheath; and the first sheath and the second sheath positioned adjacent each other. The UNLV novel sensor can be made by removing outer layers in a segment of coaxial cable, leaving a continuous link of essentially uncovered conductor between two coaxial cable legs.

Conductor-polymer composite electrode materials

DOEpatents

Ginley, D.S.; Kurtz, S.R.; Smyrl, W.H.; Zeigler, J.M.

1984-06-13

A conductive composite material useful as an electrode, comprises a conductor and an organic polymer which is reversibly electrochemically dopable to change its electrical conductivity. Said polymer continuously surrounds the conductor in intimate electrical contact therewith and is prepared by electrochemical growth on said conductor or by reaction of its corresponding monomer(s) on said conductor which has been pre-impregnated or pre-coated with an activator for said polymerization. Amount of the conductor is sufficient to render the resultant composite electrically conductive even when the polymer is in an undoped insulating state.

Flat conductor cable design, manufacture, and installation

NASA Technical Reports Server (NTRS)

Angele, W.; Hankins, J. D.

1973-01-01

Pertinent information for hardware selection, design, manufacture, and quality control necessary for flat conductor cable interconnecting harness application is presented. Comparisons are made between round wire cable and flat conductor cable. The flat conductor cable interconnecting harness systems show major cost, weight, and space savings, plus increased system performance and reliability. The design application section includes electrical characteristics, harness design and development, and a full treatise on EMC considerations. Manufacturing and quality control sections pertain primarily to the developed conductor-contact connector system and special flat conductor cable to round wire cable transitions.

Miniature intermittent contact switch

NASA Technical Reports Server (NTRS)

Sword, A.

1972-01-01

Design of electric switch for providing intermittent contact is presented. Switch consists of flexible conductor surrounding, but separated from, fixed conductor. Flexing of outside conductor to contact fixed conductor completes circuit. Advantage is small size of switch compared to standard switches.

Reactive conductors for increased efficiency of exploding foil initiators and other detonators

DOEpatents

Morris, Christopher J.; Wilkins, Paul; May, Chadd; Zakar, Eugene

2015-05-05

Provided among other things are reactive energetic material systems used for conductors in detonators for increased efficiencies. According to an embodiment, a detonator may include: a conductor including at least two constituents including (i) an electrically conductive constituent, and (ii) an electrically non-conductive constituent, that when subjected to sufficient electrical energy, result in an exothermic reaction; and a flyer plate having a non-conductive surface in contact with said conductor. When the sufficient electrical energy is supplied to said conductor, rapid heating and vaporization of at least a portion of the conductor occurs so as to explosively drive at least a portion of the flyer plate away from said conductor. In an embodiment, a multilayer conductor may be formed of alternating layers of at least one electrically conductive layer, and at least one electrically non-conductive layer, that when subjected to sufficient electrical energy, result in an exothermic reaction.

United States Air Force Summer Research Program 1991. Summer Faculty Research Program (SFRP) Reports. Volume 5A. Wright Laboratory

DTIC Science & Technology

1992-01-09

consolidated into this aniuai report. 14. SUBJECT TERMS IS. NUMBER OF PAGi:S 16. P ’.RCE CODE 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION 19...Tc(Jop), the conductor is perfectly superconducting and carries the entirety of the operating current Iop. This implies no heat generation and P = 0...further found that the code cannot converge as is. See Appendix A. 2. The subject of developing a numerical scheme capable of handling both the incom

ONR Far East Scientific Bulletin. Volume 7. Number 3. July-September 1982.

DTIC Science & Technology

1982-01-01

Ejiri, F. Sugawara, H . Onuki , M. Hirano, and T. Yao, J. Phys. Soc. Japan 50, 45 (1981), A "Fluorescent Emission and Scattering Spectra of Lithium...a consultant in information systems in the Southern California area. Leon H -. Fisher, presently on the staff of ONR Far East, is on leave from...basic and applied work on thin f ilm and bulk superconductors as well as -multif ilamentary * conductor development. John H . Hubbell is a physicist at

Average value of the shape and direction factor in the equation of refractive index

NASA Astrophysics Data System (ADS)

Zhang, Tao

2017-10-01

The theoretical calculation of the refractive indices is of great significance for the developments of new optical materials. The calculation method of refractive index, which was deduced from the electron-cloud-conductor model, contains the shape and direction factor 〈g〉. 〈g〉 affects the electromagnetic-induction energy absorbed by the electron clouds, thereby influencing the refractive indices. It is not yet known how to calculate 〈g〉 value of non-spherical electron clouds. In this paper, 〈g〉 value is derived by imaginatively dividing the electron cloud into numerous little volume elements and then regrouping them. This paper proves that 〈g〉 = 2/3 when molecules’ spatial orientations distribute randomly. The calculations of the refractive indices of several substances validate this equation. This result will help to promote the application of the calculation method of refractive index.

The Influence of Age and Skull Conductivity on Surface and Subdermal Bipolar EEG Leads

PubMed Central

Wendel, Katrina; Väisänen, Juho; Seemann, Gunnar; Hyttinen, Jari; Malmivuo, Jaakko

2010-01-01

Bioelectric source measurements are influenced by the measurement location as well as the conductive properties of the tissues. Volume conductor effects such as the poorly conducting bones or the moderately conducting skin are known to affect the measurement precision and accuracy of the surface electroencephalography (EEG) measurements. This paper investigates the influence of age via skull conductivity upon surface and subdermal bipolar EEG measurement sensitivity conducted on two realistic head models from the Visible Human Project. Subdermal electrodes (a.k.a. subcutaneous electrodes) are implanted on the skull beneath the skin, fat, and muscles. We studied the effect of age upon these two electrode types according to the scalp-to-skull conductivity ratios of 5, 8, 15, and 30 : 1. The effects on the measurement sensitivity were studied by means of the half-sensitivity volume (HSV) and the region of interest sensitivity ratio (ROISR). The results indicate that the subdermal implantation notably enhances the precision and accuracy of EEG measurements by a factor of eight compared to the scalp surface measurements. In summary, the evidence indicates that both surface and subdermal EEG measurements benefit better recordings in terms of precision and accuracy on younger patients. PMID:20130812

Vertically aligned gas-insulated transmission line having particle traps at the inner conductor

DOEpatents

Dale, Steinar J.

1984-01-01

Gas insulated electrical apparatus having first and second conductors separated by an insulating support within an insulating gas environment, and particle traps disposed along the surface of the high potential conductor for trapping and inactivating foreign particles which may be present within the insulating gas medium. Several embodiments of the invention were developed which are particularly suited for vertically aligned gas insulated transmission lines. The particle traps are grooves or cavities formed into the walls of the tubular inner conductor, without extending into the hollow portion of the conductor. In other embodiments, the traps are appendages or insert flanges extending from the inner conductor, with the insulator supports contacting the appendages instead of the inner conductor.

High-field double-pancake superconducting coils and a method of winding

DOEpatents

Materna, P.A.

1984-01-31

A double-pancake coil having first and second pancakes may comprise a plurality of conductor means, each conductor means having a different grade and having one or more conductors, wherein each pancake of said double-pancake coil is comprised of inner and outer turns; wherein said inner turns are comprised of at least one of said conductor means wound about an axis and nested within one another; wherein said outer turns are comprised of said inner conductor means and at least one other conductor means co-wound about said inner turns and nested within one another; wherein each of said conductor means is wound along said axis from said first pancake to said second pancake at a different turn.

High-field double-pancake superconducting coils and a method of winding

DOEpatents

Materna, Peter A.

1985-01-01

A double-pancake coil having first and second pancakes may comprise a plurality of conductor means, each conductor means having a different grade and having one or more conductors, wherein each pancake of said double-pancake coil is comprised of inner and outer turns; wherein said inner turns are comprised of at least one of said conductor means wound about an axis and nested within one another; wherein said outer turns are comprised of said inner conductor means and at least one other conductor means co-wound about said inner turns and nested within one another; wherein each of said conductor means is wound along said axis from said first pancake to said second pancake at a different turn.

Modeling of transmission line exposure to direct lightning strokes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rizk, F.A.M.

1990-10-01

The paper introduces a new model for assessing the exposure of free-standing structures and horizontal conductors above flat ground to direct lightning strokes. The starting point of this work is a recently developed criterion for positive leader inception, modified to account for positive leaders initiated under the influence of a negative descending lightning stroke. Subsequent propagation of the positive leader is analyzed to define the point of encounter of the two leaders which determines the attractive radius of a structure or the attractive lateral distance of a conductor. These parameters are investigated for a wide range of heights and return-strokemore » currents. A method for analyzing shielding failure and determining the critical shielding angle is also described. The predictions of the model are compared with field observations and previously developed models.« less

30 CFR 56.12010 - Isolation or insulation of communication conductors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conductors. 56.12010 Section 56.12010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... MINES Electricity § 56.12010 Isolation or insulation of communication conductors. Telephone and low... energized power conductors or any other power source. ...

30 CFR 56.12010 - Isolation or insulation of communication conductors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conductors. 56.12010 Section 56.12010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... MINES Electricity § 56.12010 Isolation or insulation of communication conductors. Telephone and low... energized power conductors or any other power source. ...

Analyse dynamique des lignes de grande portee sous charges de vent

NASA Astrophysics Data System (ADS)

Ashby, Mathieu

There are two types of electric crossing : i) subterranean / submarine line ii) overhead-line crossing. We always consider the last one as a more economic option. The inconvenience of an overhead-line crossing would be the environmental constraints among which the existing obstacles, the clearance for the navigation and the aesthetics demanded by the public. The overhead-line crossings usually have conductors of long ranges which are outside of the field of application for the current transmission line codes. These are limited to reaches of a length included between 200 m and 800 m, as well as a height of support lower than 60 m. However, for reaches over 800 m and over a height over 60 m, the criteria of conception in the transmission line codes for the calculation of wind loads are not applicable. In this study we concentrate on loads on the supports owed to the limit wind applied to bare conductors and insulators chains The objective of the present study is to examine the effect of the temporal and spatial correlation of the wind load along the conductors on a finite element model. A special attention was brought to the evaluation of the importance of the dynamic load transmitted on by the conductors and the insulators chains for the case of a turbulent wind load. The numerical study on finite element model for the example of a overhead-line crossing was done with the software ADINA. The wind load for the finite element model for the example of a overhead-line crossing was generated by the software WindGen which uses the method of Simiu-Scanlan and the method of spectral representation developed by Shinozuka-Deodatis. Wind loads generated where integrated into the finite element model ADINA for a dynamic analysis of the overhead-line crossing. For the first part, the current methods are used to calculate the efforts in supports due to the wind loads with an engineering approach and a comparaison approach. The current methods are then compared with the efforts obtained from an advanced method, transient dynamic and spectral stochastic, and specifically for the case of a simple overhead-line and an overhead-line crossings. For the second part, the effect of the longitudinal correlation of the wind load on two parallel conductors was examined. Finally, dynamic experiments on an insulators chain were made to determine the variation of the damping and the rigidity of the system for different type of insulators, different speed of application of the load and the inclination of the insulator. Key words : transient dynamics, spectral stochastic, turbulent wind, conductor, aerodynamic damping, structural damping, spatial correlation, wind spectra

Collective phenomena in the early stages of relativistic heavy-ion collisions

NASA Astrophysics Data System (ADS)

Ryblewski, Radoslaw

Geophysical signatures of volcano-hosted geothermal systems in Indonesia are compiled and synthesized. Parameters include electrical resistivity, seismicity, downhole logging, and pressure/temperature data; temperature and pressure states of systems are simulated through numerical models. The systems are Sungai Penuh, Hululais, Lumutbalai, Ulubelu, Kamojang, Kotamobagu, Tompaso, and Lahendong. The general resistivity structure of the systems comprises a vertical conductor under the volcano peak (<10 ohm.m), a lateral conductor under the volcano flank (<10 ohm.m), and an intermediate resistivity zone under the lateral conductor. Background formations are generally resistive with a resistivity >70 ohm.m. The vertical conductor is the expression of either an active or inactive volcanic neck / magmatic chimney. The lateral conductor is the claycap of the geothermal system containing an argillic alteration zone that keeps the hot fluids and the heat inside the reservoir. The topography of the volcano dictates the hydrology and shapes the extent of the lateral conductor. The hydrothermal fluids themselves are kept within the intermediate resistivity region, 10--60 ohm.m for a liquid-dominated system, and up to 100 ohm.m for a vapor-dominated system, preferably with the temperature of 200--300 ° C. On the margins, the reservoir may have either sharp or diffuse contact with the background or the claycap; vapor-dominated systems have a sharp contact. A diffuse contact is usually associated with a gradational change in temperature, with temperature reversal at depth. The caprock of a geothermal system has an aseismic character possibly due to its ductile behavior from the clay and from its low permeability structure. The low permeability property impedes liquid movement and flashing that could induce seismicity. The propylitic reservoir is seismogenic due to less clay content and its high permeability that promotes liquid movement and flashing into steam which induces seismicity. Modeling studies suggest that the most favorable permeability configuration for a vapor-dominated reservoir similar to Kamojang contains a caprock with the permeability of 3 x 10 -16 m2 accompanied with a recharge region/hostrock having the permeability of 10-18 m2 to 10-17 m2. A heat flow of 8 MW/km 2 for 9 kyr is the minimum combination to produce a thick vapor-dominated zone (> 1000 meter) in a 2.8 km thick reservoir with the permeability of 10-13 m 2. Model simulations are produced that reach steady state at 10.7 kyr, with 38--40 bar and 250--252 ° C reservoir yielding a heatloss of 90 MW and 35 kg/s of steam escaping from the reservoir. This study provided an unusual opportunity to characterize and model volcano-hosted geothermal systems.

A QR accelerated volume-to-surface boundary condition for finite element solution of eddy current problems

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, D; Fasenfest, B; Rieben, R

2006-09-08

We are concerned with the solution of time-dependent electromagnetic eddy current problems using a finite element formulation on three-dimensional unstructured meshes. We allow for multiple conducting regions, and our goal is to develop an efficient computational method that does not require a computational mesh of the air/vacuum regions. This requires a sophisticated global boundary condition specifying the total fields on the conductor boundaries. We propose a Biot-Savart law based volume-to-surface boundary condition to meet this requirement. This Biot-Savart approach is demonstrated to be very accurate. In addition, this approach can be accelerated via a low-rank QR approximation of the discretizedmore » Biot-Savart law.« less

30 CFR Appendix I to Subpart D of... - Appendix I to Subpart D of Part 18

Code of Federal Regulations, 2013 CFR

2013-07-01

... 60 °C. copper temperature (40 °C. ambient) Resistance at 60 °C. copper temperature (ohms) 6 550 50 0... Temperature—40 °C. Ambient) Conductor size—AWG or MCM Single conductor 2-conductor, round or flat 3-conductor... 2—Portable Cord Ampacities—600 Volts (Amperes Per Conductor Based on 60 °C. Copper Temperature—40 °C...

Superconducting magnet cooling system

DOEpatents

Vander Arend, Peter C.; Fowler, William B.

1977-01-01

A device is provided for cooling a conductor to the superconducting state. The conductor is positioned within an inner conduit through which is flowing a supercooled liquid coolant in physical contact with the conductor. The inner conduit is positioned within an outer conduit so that an annular open space is formed therebetween. Through the annular space is flowing coolant in the boiling liquid state. Heat generated by the conductor is transferred by convection within the supercooled liquid coolant to the inner wall of the inner conduit and then is removed by the boiling liquid coolant, making the heat removal from the conductor relatively independent of conductor length.

Thermal oxidative degradation of ethylene tetrafluoroethylene copolymer systems

NASA Astrophysics Data System (ADS)

Elders, Jonathan Patrick

Thermo-oxidative degradation of ethylene tetrafluoroethylene (ETFE) was investigated to determine how modifications for use in an electrical wire system affected its thermal stability. Modifications included electron irradiation and subsequent cross-linking during manufacture and contact with a metal surface. Samples with irradiation histories between 0 and 48 MRads were investigated. Degradation of ETFE was enhanced by contact with a metal "conductor" surface: silver - coated copper. Polymer degradation was analyzed by weight loss kinetics (thermogravimetric analysis (TGA)), changes in polymer morphology (differential scanning calorimetry (DSC)), optical microscopy, attenuated total reflectance (ATR) infrared spectroscopy, and gas chromatography - mass spectroscopy (GC/MS). Conductor aging (copper permeation through silver with subsequent oxidation) was investigated using scanning Auger Electron Spectroscopy (AES). Conductor aging is enhanced in the presence of the polymer surface. Interactions between conductor and polymer were analyzed by optical microscopy, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The rate of polymer degradation from 220°C to 280°C was independent of time and extent of degradation, and rate was proportional to irradiation dose. The activation energy for degradation of unirradiated ETFE was 227 kJ/mol and decreased from 150 to 138 kJ/mol for ETFE irradiated to doses between 6 and 48 MRads. Rates of degradation at 300°C to 320°C were dependent on the extent of degradation. Rates of degradation at temperatures between 230°C and 310°C were an order of magnitude larger in the presence of a conductor than in its absence, and activation energies for degradation in the presence of conductor were reduced to 120 kJ/mol. Degradation was modeled as the combination of bulk polymer degradation and catalytic degradation at the polymer-metal interface. ETFE aged at 250°C in the presence or absence of a conductor exhibited a double melting endotherm. ATR spectra of aged ETFE indicated polymer oxidation. Based on AES experiments, copper permeation during aging in the presence or absence of ETFE was consistent with Fickian diffusion. The coefficient for copper diffusion through silver was approximately 10 -15 cm2/second, and catalytic ETFE degradation was proportional to conductor aging. The copper oxidized on the surface to yield a material with a stoichiometric composition of Cu3O 2.

Method and apparatus for preparing multiconductor cable with flat conductors

NASA Technical Reports Server (NTRS)

Marcell, G. V. (Inventor)

1969-01-01

A method and apparatus for preparing flat conductor cable having a plurality of ribbon-like conductors disposed upon and adhesively bonded to the surface of a substrate is described. The conductors are brought into contact with the substrate surface, and while maintained in axial tension on said substrate, the combination is seated on a yieldably compressible layer to permit the conductor to become embedded into the surface of the substrate film.

Effect of EEG electrode density on dipole localization accuracy using two realistically shaped skull resistivity models.

PubMed

Laarne, P H; Tenhunen-Eskelinen, M L; Hyttinen, J K; Eskola, H J

2000-01-01

The effect of number of EEG electrodes on the dipole localization was studied by comparing the results obtained using the 10-20 and 10-10 electrode systems. Two anatomically detailed models with resistivity values of 177.6 omega m and 67.0 omega m for the skull were applied. Simulated potential values generated by current dipoles were applied to different combinations of the volume conductors and electrode systems. High and low resistivity models differed slightly in favour of the lower skull resistivity model when dipole localization was based on noiseless data. The localization errors were approximately three times larger using low resistivity model for generating the potentials, but applying high resistivity model for the inverse solution. The difference between the two electrode systems was minor in favour of the 10-10 electrode system when simulated, noiseless potentials were used. In the presence of noise the dipole localization algorithm operated more accurately using the denser electrode system. In conclusion, increasing the number of recording electrodes seems to improve the localization accuracy in the presence of noise. The absolute skull resistivity value also affects the accuracy, but using an incorrect value in modelling calculations seems to be the most serious source of error.

Decomposing the electromagnetic response of magnetic dipoles to determine the geometric parameters of a dipole conductor

NASA Astrophysics Data System (ADS)

Desmarais, Jacques K.; Smith, Richard S.

2016-03-01

A novel automatic data interpretation algorithm is presented for modelling airborne electromagnetic (AEM) data acquired over resistive environments, using a single-component (vertical) transmitter, where the position and orientation of a dipole conductor is allowed to vary in three dimensions. The algorithm assumes that the magnetic fields produced from compact vortex currents are expressed as a linear combinations of the fields arising from dipoles in the subsurface oriented parallel to the [1, 0, 0], [0, 1, 0], and [0, 0, 1], unit vectors. In this manner, AEM responses can be represented as 12 terms. The relative size of each term in the decomposition can be used to determine geometrical information about the orientation of the subsurface conductivity structure. The geometrical parameters of the dipole (location, depth, dip, strike) are estimated using a combination of a look-up table and a matrix inverted in a least-squares sense. Tests on 703 synthetic models show that the algorithm is capable of extracting most of the correct geometrical parameters of a dipole conductor when three-component receiver data is included in the interpretation procedure. The algorithm is unstable when the target is perfectly horizontal, as the strike is undefined. Ambiguities may occur in predicting the orientation of the dipole conductor if y-component data is excluded from the analysis. Application of our approach to an anomaly on line 15 of the Reid Mahaffy test site yields geometrical parameters in reasonable agreement with previous authors. However, our algorithm provides additional information on the strike and offset from the traverse line of the conductor. Disparities in the values of predicted dip and depth are within the range of numerical precision. The index of fit was better when strike and offset were included in the interpretation procedure. Tests on the data from line 15701 of the Chibougamau MEGATEM survey shows that the algorithm is applicable to situations where three-component AEM data is available.

33 CFR 159.73 - Conductors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must be...

30 CFR 7.403 - Application requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., round or flat). (iii) Number and size (gauge) of each conductor. (iv) Voltage rating for all cables containing electric conductors. (v) For electric cables, current-carrying capacity of each conductor, with corresponding ambient temperature upon which the current rating (ampacity) is based, of each power conductor. (2...

33 CFR 159.73 - Conductors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must be...

30 CFR 57.12010 - Isolation or insulation of communication conductors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conductors. 57.12010 Section 57.12010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... conductors. Telephone and low-potential signal wire shall be protected, by isolation or suitable insulation, or both, from contacting energized power conductors or any other power source. ...

30 CFR 57.12010 - Isolation or insulation of communication conductors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conductors. 57.12010 Section 57.12010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... conductors. Telephone and low-potential signal wire shall be protected, by isolation or suitable insulation, or both, from contacting energized power conductors or any other power source. ...

Electrostatic separation for recycling conductors, semiconductors, and nonconductors from electronic waste.

PubMed

Xue, Mianqiang; Yan, Guoqing; Li, Jia; Xu, Zhenming

2012-10-02

Electrostatic separation has been widely used to separate conductors and nonconductors for recycling e-waste. However, the components of e-waste are complex, which can be classified as conductors, semiconductors, and nonconductors according to their conducting properties. In this work, we made a novel attempt to recover the mixtures containing conductors (copper), semiconductors (extrinsic silicon), and nonconductors (woven glass reinforced resin) by electrostatic separation. The results of binary mixtures separation show that the separation of conductor and nonconductor, semiconductor and nonconductor need a higher voltage level while the separation of conductor and semiconductor needs a higher roll speed. Furthermore, the semiconductor separation efficiency is more sensitive to the high voltage level and the roll speed than the conductor separation efficiency. An integrated process was proposed for the multiple mixtures separation. The separation efficiency of conductors and semiconductors can reach 82.5% and 88%, respectively. This study contributes to the efficient recycling of valuable resources from e-waste.

A computer program to perform dynamic thermal analysis for bare overhead conductors during short-time overload conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shrestha, P.; Pham, K.

1995-12-31

Under emergency conditions, a bare overhead conductor can carry an increased amount of current that is well in excess of its normal rating. When there is this increase in current flow on a bare overhead conductor, the temperature does not rise instantaneously. but increases along a curve determined by the current, the conductor properties and the ambient conditions. The conductor temperature at the end of a short-time overload period must be restricted to its maximum design value. This paper presents a simplified approach in analyzing the dynamic performance for bare overhead conductors during short-time overload condition. A computer program wasmore » developed to calculate the short-time ratings for bare overhead conductors. The following parameters: current induced heating. solar load, convective/conductive cooling, radiative cooling, altitude, wind velocity and ampacity of the bare conductor were considered. Several sample graphical output lots are included with the paper.« less

Structure for monolithic optical circuits

NASA Technical Reports Server (NTRS)

Evanchuk, Vincent L. (Inventor)

1984-01-01

A method for making monolithic optical circuits, with related optical devices as required or desired, on a supporting surface (10) consists of coating the supporting surface with reflecting metal or cladding resin, spreading a layer of liquid radiation sensitive plastic (12) on the surface, exposing the liquid plastic with a mask (14) to cure it in a desired pattern of light conductors (16, 18, 20), washing away the unexposed liquid plastic, and coating the conductors thus formed with reflective metal or cladding resin. The index of refraction for the cladding (22) is selected to be lower than for the conductors so that light in the conductors will be reflected by the interface with the cladding. For multiple level conductors, as where one conductor must cross over another, the process may be repeated to fabricate a bridge with columns (24, 26) of conductors to the next level, and conductor (28) between the columns. For more efficient transfer of energy over the bridge, faces at 45.degree. may be formed to reflect light up and across the bridge.

The influence of the local structure on proton transport in a solid oxide proton conductor La 0.8 Ba 1.2 GaO 3.9

DOE PAGES

Cheng, Yongqiang; Balachandran, Janakiraman; Bi, Zhonghe; ...

2017-07-18

The local structure around the mobile ions influences their dynamics. The knowledge about the relationship between these properties is of fundamental importance and may lead the way for development of improved solid state ionic conductors. Here, we use inelastic neutron scattering and ab initio modeling to study a representative proton conductor, La 0.8Ba 1.2GaO 3.9, where different local structures are possible for the same stoichiometry. The intrinsic correlations between the local bonding environment and the dynamical behavior of protons are presented. In particular, we identify how the local Ba/La concentration affects the proton vibrational frequencies, hydrogen bond strength, O–H rotationsmore » and in turn long-range proton mobility. Furthermore, possible mechanism for proton transport, through the inter-tetrahedral bond switching, O–H rotations and tetrahedral reorientation is anticipated.« less

Hard X-ray and low-energy gamma-ray spectrometers

NASA Technical Reports Server (NTRS)

Gehrels, N.; Crannell, C. J.; Orwig, L. E.; Forrest, D. J.; Lin, R. P.; Starr, R.

1988-01-01

Basic principles of operation and characteristics of scintillation and semi-conductor detectors used for solar hard X-ray and gamma-ray spectrometers are presented. Scintillation materials such as NaI offer high stopping power for incident gamma rays, modest energy resolution, and relatively simple operation. They are, to date, the most often used detector in solar gamma-ray spectroscopy. The scintillator BGO has higher stopping power than NaI, but poorer energy resolution. The primary advantage of semi-conductor materials such as Ge is their high-energy resolution. Monte-Carlo simulations of the response of NaI and Ge detectors to model solar flare inputs show the benefit of high resoluton for studying spectral lines. No semi-conductor material besides Ge is currently available with adequate combined size and purity to make general-use hard X-ray and gamma-ray detectors for solar studies.

IC(B,T,STRAIN) Characterisation of a Nb3Sn Internal Tin Strand with Enhanced Specification for Use in Fusion Conductors

NASA Astrophysics Data System (ADS)

Pasztor, G.; Bruzzone, P.

2004-06-01

The dc performance of a recently produced internal tin route Nb3Sn strand with enhanced specification is studied extensively and compared with predecessor wires manufactured by the suppliers for the ITER Model Coils in 1996. The wire has been selected for use in a full size, developmental cable-in-conduit conductor sample, which is being tested in the SULTAN Test Facility. The critical current, Ic, and the index of the current/voltage characteristic, n, are measured over a broad range of field and temperature, using ITER standard sample holders, made of TiAlV grooved cylinders. The behavior of Ic versus applied tensile strain is also investigated at 4.2 K and 12 T, on straight specimens. Scaling law parameters are drawn from the fit of the experimental results. The implications of the test results to the design of the fusion conductors are discussed.

Downhole transmission system

DOEpatents

Hall, David R [Provo, UT; Fox, Joe [Spanish Fork, UT

2008-01-15

A transmission system in a downhole component comprises a data transmission element in both ends of the downhole component. Each data transmission element houses an electrically conducting coil in a MCEI circular trough. An electrical conductor connects both the transmission elements. The electrical conductor comprises at least three electrically conductive elements insulated from each other. In the preferred embodiment the electrical conductor comprises an electrically conducting outer shield, an electrically conducting inner shield and an electrical conducting core. In some embodiments of the present invention, the electrical conductor comprises an electrically insulating jacket. In other embodiments, the electrical conductor comprises a pair of twisted wires. In some embodiments, the electrical conductor comprises semi-conductive material.

Cluster-inspired Superionic Conductors

NASA Astrophysics Data System (ADS)

Fang, Hong; Jena, Puru

Superionic conductors with desirable properties hold the key to the development of next generation of rechargeable metal-ion batteries. In this study, we report a new family of superionic conductors composed by clusters based on the antiperovskite fast-ion conductors. The new lightweight conductor shows larger electrochemical stability window and favorable thermal and mechanical properties, while maintain a high Li+-ionconductivity at room temperature and a low activation energy. We reveal the conduction mechanism of the material by identifying the relation between the orientational symmetry of the cluster rotors and the potential surface felt by the lithium ion. We also find that the mixed phase of the new conductors show further enhanced conductivity.

Multiwire conductor having greatly increased interwire resistance and method for making same

DOEpatents

Luhman, Thomas; Suenaga, Masaki

1984-01-17

An improved multiwire conductor of the type which is mechanically stabilized by a tin based solder filler. A solder filled conductor is heated to a temperature above its melting point for a period long enough to allow a substantial amount of copper to be dissolved from the wires comprising the conductor. The copper forms the brittle intermetallic compound Cu.sub.5 Sn.sub.6 with tin in the solder. After cooling the conductor is flexed causing a random cracking of the solder, and thereby increasing the interwire resistance of the conductor. The subject invention is particularly adapted for use with braided, ribbon-type solder filled superconductors.

Multiwire conductor having increased interwire resistance and good mechanical stability and method for making same

DOEpatents

Luhman, Thomas; Klamut, Carl

1984-02-14

An improved multiwire conductor of the type which is mechanically stabilized by a solder filler. A solder filled conductor is heated to a temperature sufficient to make the solder brittle, but below the melting point of the solder. While still hot, the conductor is flexed, causing the solder to separate from the wires comprising the conductor, thereby increasing the interwire resistance. In one embodiment the conductor may be heated to a temperature above the eutectic temperature of the solder so that a controlled amount of solder is removed. The subject invention is particularly suited for use with braided, ribbon-type, solder filled superconductors.

Multiwire conductor having increased interwire resistance and good mechanical stability and method for making same

DOEpatents

Luhman, T.; Klamut, C.

1982-03-15

An improved multiwire conductor of the type which is mechanically stabilized by a solder filler. A solder filled conductor is heated to a temperature sufficient to make the solder brittle, but below the melting point of the solder. While still hot, the conductor is flexed, causing the solder to separate from the wires comprising the conductor, thereby increasing the interwire resistance. In one embodiment the conductor may be heated to a temperature above the eutectic temperature of the solder so that a controlled amount of solder is removed. The subject invention is particularly suited for use with braided, ribbon-type, solder filled superconductors.

MQXFS1 Quadrupole Fabrication Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ambrosio, G.; Anerella, M.; Bossert, R.

This report presents the fabrication and QC data of MQXFS1, the first short model of the low-beta quadrupoles (MQXF) for the LHC High Luminosity Upgrade. It describes the conductor, the coils, and the structure that make the MQXFS1 magnet. Qualification tests and non-conformities are also presented and discussed. The fabrication of MQXFS1 was started before the finalization of conductor and coil design for MQXF magnets. Two strand design were used (RRP 108/127 and RRP 132/169). Cable and coil cross-sections were “first generation”.

Solving time-dependent two-dimensional eddy current problems

NASA Technical Reports Server (NTRS)

Lee, Min Eig; Hariharan, S. I.; Ida, Nathan

1990-01-01

Transient eddy current calculations are presented for an EM wave-scattering and field-penetrating case in which a two-dimensional transverse magnetic field is incident on a good (i.e., not perfect) and infinitely long conductor. The problem thus posed is of initial boundary-value interface type, where the boundary of the conductor constitutes the interface. A potential function is used for time-domain modeling of the situation, and finite difference-time domain techniques are used to march the potential function explicitly in time. Attention is given to the case of LF radiation conditions.

30 CFR 75.1002 - Installation of electric equipment and conductors; permissibility.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conductors; permissibility. 75.1002 Section 75.1002 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Wires and Trolley Feeder Wires § 75.1002 Installation of electric equipment and conductors... equipment is located within 150 feet of pillar workings or longwall faces. (b) Electric conductors and...

30 CFR 75.513 - Electric conductor; capacity and insulation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. [Statutory Provision] All electric conductors...

30 CFR 75.700 - Grounding metallic sheaths, armors, and conduits enclosing power conductors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conduits enclosing power conductors. 75.700 Section 75.700 Mineral Resources MINE SAFETY AND HEALTH... Grounding § 75.700 Grounding metallic sheaths, armors, and conduits enclosing power conductors. [Statutory Provisions] All metallic sheaths, armors, and conduits enclosing power conductors shall be electrically...

30 CFR 77.700 - Grounding metallic sheaths, armors, and conduits enclosing power conductors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conduits enclosing power conductors. 77.700 Section 77.700 Mineral Resources MINE SAFETY AND HEALTH..., and conduits enclosing power conductors. Metallic sheaths, armors, and conduits enclosing power conductors shall be electrically continuous throughout and shall be grounded by methods approved by an...

30 CFR 75.700 - Grounding metallic sheaths, armors, and conduits enclosing power conductors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conduits enclosing power conductors. 75.700 Section 75.700 Mineral Resources MINE SAFETY AND HEALTH... Grounding § 75.700 Grounding metallic sheaths, armors, and conduits enclosing power conductors. [Statutory Provisions] All metallic sheaths, armors, and conduits enclosing power conductors shall be electrically...

46 CFR 129.380 - Overcurrent protection.

Code of Federal Regulations, 2011 CFR

2011-10-01

... protection must be provided for each ungrounded conductor, to open the electric circuit if the current reaches a value that causes an excessive or dangerous temperature in the conductor or its insulation. (b) Each conductor of a control, interlock, or indicator circuit, such as a conductor for an instrument...

46 CFR 120.380 - Overcurrent protection.

Code of Federal Regulations, 2010 CFR

2010-10-01

... for each ungrounded conductor for the purpose of opening the electric circuit if the current reaches a value that causes an excessive or dangerous temperature in the conductor or conductor insulation. (b) The grounded conductor of a circuit must not be disconnected by a switch or circuit breaker, unless...

46 CFR 120.380 - Overcurrent protection.

Code of Federal Regulations, 2011 CFR

2011-10-01

... for each ungrounded conductor for the purpose of opening the electric circuit if the current reaches a value that causes an excessive or dangerous temperature in the conductor or conductor insulation. (b) The grounded conductor of a circuit must not be disconnected by a switch or circuit breaker, unless...

30 CFR 77.700 - Grounding metallic sheaths, armors, and conduits enclosing power conductors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conduits enclosing power conductors. 77.700 Section 77.700 Mineral Resources MINE SAFETY AND HEALTH..., and conduits enclosing power conductors. Metallic sheaths, armors, and conduits enclosing power conductors shall be electrically continuous throughout and shall be grounded by methods approved by an...

30 CFR 75.1002 - Installation of electric equipment and conductors; permissibility.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conductors; permissibility. 75.1002 Section 75.1002 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Wires and Trolley Feeder Wires § 75.1002 Installation of electric equipment and conductors... equipment is located within 150 feet of pillar workings or longwall faces. (b) Electric conductors and...

30 CFR 75.513 - Electric conductor; capacity and insulation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. [Statutory Provision] All electric conductors...

46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Equipment safety grounding (bonding) conductors. 111.05... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-33 Equipment safety grounding (bonding) conductors. (a) Each equipment-grounding conductor must...

46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Equipment safety grounding (bonding) conductors. 111.05... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-33 Equipment safety grounding (bonding) conductors. (a) Each equipment-grounding conductor must...

46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Equipment safety grounding (bonding) conductors. 111.05... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-33 Equipment safety grounding (bonding) conductors. (a) Each equipment-grounding conductor must...

33 CFR 159.71 - Electrical controls and conductors.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors must...

33 CFR 159.71 - Electrical controls and conductors.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors must...

33 CFR 159.71 - Electrical controls and conductors.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors must...

Mixed ionic-electronic conductors for electrodes of barium cerate-based SOFCS

NASA Astrophysics Data System (ADS)

Wu, Zhonglin

Gadolinium doped barium cerates (BCGs) have been identified as promising electrolyte materials for intermediate-temperature solid oxide fuel cells (SOFCs). It is crucial to develop compatible electrode materials for such electrolytes. Mixed ionic-electronic conductor (MIEC) electrode materials developed for SOFCs based on yttrium-stabilized zirconia (YSZ) may be used as electrode materials for BCG-based SOFCs; but a careful re-evaluation is required due to the intrinsic differences between BCG and YSZ. The performance of these electrode materials depends critically the transport of ionic and electronic species as well as gas. Accordingly, a profound understanding of transport in MIEC electrodes is imperative to effective design of high performance SOFCs. In this thesis, ambipolar transport in composite MIEC electrodes has been modeled using percolation theory to predict the effect of volume fractions of constituent phases and porosity on ambipolar conductivity. Transport and electrode kinetics of homogeneous MIEC electrodes have also been formulated under a steady-state condition to predict the distributions of ionic defects and current carried by each defect in such electrodes. Effects of catalytic properties, transport properties, and microstructure of porous electrodes and interfaces on the electrode performance are investigated. Under the guidelines of the theoretical modeling, several MIEC electrode materials are developed. Lasb{1-x}Srsb{x}Cosb{1-x}Fesb{y}Osb{3-delta} homogeneous materials are studied as cathode materials. However, the interfacial resistance seems too high due to the lack of catalytic activity at intermediate temperatures. Results indicate that Ag-Bisb{1.5}Ysb{0.5}Osb3 composite MIECs are good cathode materials when the volume fractions of constituent phases and porosity are carefully controlled. Such electrodes have low interfacial resistance, better binding strength, and smaller thermal mismatch with the BCG electrolyte, compared to other metal electrodes (such as Pt and Ag). Ni-BCG composite MIECs are studied as anode materials. It is found that electrodes prepared from NiO and reduced to Ni in situ is not catalytically active because of diffusion of NiO into BCG, which forms a resistive layer. Electrodes prepared from Ni metal and fired in an inert or reducing atmosphere exhibit low interfacial resistance and good compatibility with BCG electrolyte. Stability of these developed electrode materials is investigated under conditions pertinent to SOFCs.

Resistive coating for current conductors in cryogenic applications

DOEpatents

Hirayama, Chikara; Wagner, George R.

1982-05-18

This invention relates to a resistive or semiconducting coating for use on current conductors in cryogenic applications. This includes copper-clad superconductor wire, copper wire used for stabilizing superconductor magnets, and for hyperconductors. The coating is a film of cuprous sulfide (Cu.sub.2 S) that has been found not to degrade the properties of the conductors. It is very adherent to the respective conductors and satisfies the mechanical, thermal and electrical requirements of coatings for the conductors.

High pressure, high current, low inductance, high reliability sealed terminals

DOEpatents

Hsu, John S [Oak Ridge, TN; McKeever, John W [Oak Ridge, TN

2010-03-23

The invention is a terminal assembly having a casing with at least one delivery tapered-cone conductor and at least one return tapered-cone conductor routed there-through. The delivery and return tapered-cone conductors are electrically isolated from each other and positioned in the annuluses of ordered concentric cones at an off-normal angle. The tapered cone conductor service can be AC phase conductors and DC link conductors. The center core has at least one service conduit of gate signal leads, diagnostic signal wires, and refrigerant tubing routed there-through. A seal material is in direct contact with the casing inner surface, the tapered-cone conductors, and the service conduits thereby hermetically filling the interstitial space in the casing interior core and center core. The assembly provides simultaneous high-current, high-pressure, low-inductance, and high-reliability service.

30 CFR 57.12048 - Communication conductors on power poles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Communication conductors on power poles. 57... MINES Electricity Surface and Underground § 57.12048 Communication conductors on power poles. Telegraph, telephone, or signal wires shall not be installed on the same crossarm with power conductors. When carried...

46 CFR 183.372 - Equipment and conductor grounding.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Equipment and conductor grounding. 183.372 Section 183... conductor grounding. (a) All metallic enclosures and frames of electrical equipment must be permanently... equipment must be bonded together to a common ground by a normally non-current carrying conductor. Metallic...

30 CFR 57.12005 - Protection of power conductors from mobile equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection of power conductors from mobile... NONMETAL MINES Electricity Surface and Underground § 57.12005 Protection of power conductors from mobile equipment. Mobile equipment shall not run over power conductors, nor shall loads be dragged over power...

33 CFR 183.455 - Overcurrent protection: General.

Code of Federal Regulations, 2011 CFR

2011-07-01

....455 Overcurrent protection: General. (a) Each ungrounded current-carrying conductor must be protected... breaker or fuse must be placed at the source of power for each circuit or conductor except: (1) If it is... seven inches of the source of power for each circuit or conductor measured along the conductor. (2) If...

46 CFR 120.372 - Equipment and conductor grounding.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Equipment and conductor grounding. 120.372 Section 120... INSTALLATION Power Sources and Distribution Systems § 120.372 Equipment and conductor grounding. (a) All... together to a common ground by a normally non-current carrying conductor. Metallic cases of instruments and...

46 CFR 183.380 - Overcurrent protection.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Overcurrent protection must be provided for each ungrounded conductor for the purpose of opening the electric circuit if the current reaches a value that causes an excessive or dangerous temperature in the conductor or conductor insulation. (b) The grounded conductor of a circuit must not be disconnected by a switch...

46 CFR 183.372 - Equipment and conductor grounding.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Equipment and conductor grounding. 183.372 Section 183... conductor grounding. (a) All metallic enclosures and frames of electrical equipment must be permanently... equipment must be bonded together to a common ground by a normally non-current carrying conductor. Metallic...

46 CFR 183.380 - Overcurrent protection.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Overcurrent protection must be provided for each ungrounded conductor for the purpose of opening the electric circuit if the current reaches a value that causes an excessive or dangerous temperature in the conductor or conductor insulation. (b) The grounded conductor of a circuit must not be disconnected by a switch...

30 CFR 77.503 - Electric conductors; capacity and insulation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductors; capacity and insulation... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and insulation. Electric conductors shall be sufficient in size and have adequate current carrying capacity and be of such...

30 CFR 57.12048 - Communication conductors on power poles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Communication conductors on power poles. 57... MINES Electricity Surface and Underground § 57.12048 Communication conductors on power poles. Telegraph, telephone, or signal wires shall not be installed on the same crossarm with power conductors. When carried...

30 CFR 75.513-1 - Electric conductor; size.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductor; size. 75.513-1 Section 75.513-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying...

30 CFR 56.12048 - Communication conductors on power poles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Communication conductors on power poles. 56... Electricity § 56.12048 Communication conductors on power poles. Telegraph, telephone, or signal wires shall not be installed on the same crossarm with power conductors. When carried on poles supporting...

30 CFR 77.503 - Electric conductors; capacity and insulation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductors; capacity and insulation... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and insulation. Electric conductors shall be sufficient in size and have adequate current carrying capacity and be of such...

21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Esophageal stethoscope with electrical conductors... stethoscope with electrical conductors. (a) Identification. An esophageal stethoscope with electrical conductors is a device that is inserted into the esophagus to listen to a patient's heart and breath sounds...

30 CFR 56.12048 - Communication conductors on power poles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Communication conductors on power poles. 56... Electricity § 56.12048 Communication conductors on power poles. Telegraph, telephone, or signal wires shall not be installed on the same crossarm with power conductors. When carried on poles supporting...

46 CFR 120.372 - Equipment and conductor grounding.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Equipment and conductor grounding. 120.372 Section 120... INSTALLATION Power Sources and Distribution Systems § 120.372 Equipment and conductor grounding. (a) All... together to a common ground by a normally non-current carrying conductor. Metallic cases of instruments and...

33 CFR 183.455 - Overcurrent protection: General.

Code of Federal Regulations, 2010 CFR

2010-07-01

....455 Overcurrent protection: General. (a) Each ungrounded current-carrying conductor must be protected... breaker or fuse must be placed at the source of power for each circuit or conductor except: (1) If it is... seven inches of the source of power for each circuit or conductor measured along the conductor. (2) If...

30 CFR 57.12005 - Protection of power conductors from mobile equipment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Protection of power conductors from mobile... NONMETAL MINES Electricity Surface and Underground § 57.12005 Protection of power conductors from mobile equipment. Mobile equipment shall not run over power conductors, nor shall loads be dragged over power...

21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Esophageal stethoscope with electrical conductors... stethoscope with electrical conductors. (a) Identification. An esophageal stethoscope with electrical conductors is a device that is inserted into the esophagus to listen to a patient's heart and breath sounds...

30 CFR 75.513-1 - Electric conductor; size.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductor; size. 75.513-1 Section 75.513-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying...

29 CFR 1910.305 - Wiring methods, components, and equipment for general use.

Code of Federal Regulations, 2010 CFR

2010-07-01

... distribution center. (B) Conductors shall be run as multiconductor cord or cable assemblies. However, if... persons, feeders may be run as single insulated conductors. (v) The following requirements apply to branch... shall be multiconductor cord or cable assemblies or open conductors. If run as open conductors, they...

29 CFR 1910.305 - Wiring methods, components, and equipment for general use.

Code of Federal Regulations, 2011 CFR

2011-07-01

... distribution center. (B) Conductors shall be run as multiconductor cord or cable assemblies. However, if... persons, feeders may be run as single insulated conductors. (v) The following requirements apply to branch... shall be multiconductor cord or cable assemblies or open conductors. If run as open conductors, they...

29 CFR 1910.305 - Wiring methods, components, and equipment for general use.

Code of Federal Regulations, 2013 CFR

2013-07-01

... distribution center. (B) Conductors shall be run as multiconductor cord or cable assemblies. However, if... persons, feeders may be run as single insulated conductors. (v) The following requirements apply to branch... shall be multiconductor cord or cable assemblies or open conductors. If run as open conductors, they...

29 CFR 1910.305 - Wiring methods, components, and equipment for general use.

Code of Federal Regulations, 2014 CFR

2014-07-01

... distribution center. (B) Conductors shall be run as multiconductor cord or cable assemblies. However, if... persons, feeders may be run as single insulated conductors. (v) The following requirements apply to branch... shall be multiconductor cord or cable assemblies or open conductors. If run as open conductors, they...

29 CFR 1910.305 - Wiring methods, components, and equipment for general use.

Code of Federal Regulations, 2012 CFR

2012-07-01

... distribution center. (B) Conductors shall be run as multiconductor cord or cable assemblies. However, if... persons, feeders may be run as single insulated conductors. (v) The following requirements apply to branch... shall be multiconductor cord or cable assemblies or open conductors. If run as open conductors, they...

30 CFR 75.513-1 - Electric conductor; size.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying...

30 CFR 75.513-1 - Electric conductor; size.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying...

30 CFR 75.513-1 - Electric conductor; size.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying...

30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

Code of Federal Regulations, 2011 CFR

2011-07-01

... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are adequately...

30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

Code of Federal Regulations, 2010 CFR

2010-07-01

... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are adequately...

Conditioning flat conductors for flat conductor cable production

NASA Technical Reports Server (NTRS)

1968-01-01

Apparatus can straighten, anneal, clean, and a tension to stretch a cable one percent to assure uniform cross-sectional area. A conductor passes through temperature controlled distilled water and through a toroid coil. As The conductor enters the water, steam performs the cleaning action. Quenching and annealing also take place.

46 CFR 111.50-3 - Protection of conductors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Protection of conductors. 111.50-3 Section 111.50-3...-GENERAL REQUIREMENTS Overcurrent Protection § 111.50-3 Protection of conductors. (a) Purpose. The purpose of overcurrent protection for conductors is to open the electric circuit if the current reaches a...

46 CFR 111.50-3 - Protection of conductors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Protection of conductors. 111.50-3 Section 111.50-3...-GENERAL REQUIREMENTS Overcurrent Protection § 111.50-3 Protection of conductors. (a) Purpose. The purpose of overcurrent protection for conductors is to open the electric circuit if the current reaches a...

30 CFR 77.700-1 - Approved methods of grounding.

Code of Federal Regulations, 2014 CFR

2014-07-01

... in resistance grounded systems, where the enclosed conductors are a part of the system, will be approved if a solid connection is made to the neutral conductor; in all other systems, the following... earth; (b) A solid connection to a grounding conductor, other than the neutral conductor of a resistance...

30 CFR 77.700-1 - Approved methods of grounding.

Code of Federal Regulations, 2012 CFR

2012-07-01

... in resistance grounded systems, where the enclosed conductors are a part of the system, will be approved if a solid connection is made to the neutral conductor; in all other systems, the following... earth; (b) A solid connection to a grounding conductor, other than the neutral conductor of a resistance...

Electrical structure of the central Cascadia subduction zone: The EMSLAB Lincoln Line revisited

NASA Astrophysics Data System (ADS)

Evans, Rob L.; Wannamaker, Philip E.; McGary, R. Shane; Elsenbeck, Jimmy

2014-09-01

The EMSLAB experiment was an ambitious onshore-offshore magnetotelluric (MT) transect of the Cascadia subduction zone. When completed (1985-1988), it was the largest experiment of its kind. Modeling and inversion capabilities at the time were, however, not sufficiently sophisticated to handle a fully regularized inversion of the data, including the seafloor data and bathymetric constraints, with the main final model presented based on trial and error forward modeling of the responses. Moreover, new data collected as part of the Earthscope USArray program are of higher quality due to improvements in instrument technology, and augment the original EMSLAB data set, presenting an opportunity to revisit the structure in this part of the subduction system. We have integrated the original wide-band MT data as well as several long-period stations from the original EMSLAB data set and invert these in conjunction with EMSLAB seafloor responses and new Earthscope data on land. This new composite data set has been analyzed in several ways, within a two-dimensional geometry in which conductivity is assumed to be invariant along a strike direction roughly coincident with that of the subduction zone. We have solved for fully smooth regularized models, as well as solutions that allow discontinuities in conductivity along the top surface of the descending slab. Finally, we have tested specific features in the EMSLAB model, notably a moderately shallow ( 30 km depth) forearc conductor. A feature similar to this shallow conductor is a consistent and required feature in our new inversion models, but the new models highlight the connection between the slab and what is interpreted to be an accumulation of aqueous fluids in the deep crust. The depth ( 40 km) at which the conductor intersects the slab suggests that the fluids are released by the transition of hydrous basalt to eclogite at upper greenschist facies and higher metamorphic grade. The nose of the mantle wedge has a conductivity consistent with a dry peridotite composition and thermal models of the system. At a depth of around 80 km the mantle intersecting the slab shows a slight increase in conductivity. This increase is not sufficient to require the presence of melt, but a conductor indicative of melt can be inserted into the model at this depth without compromising the fit.

The effect of conductor permeability on electric current transducers

NASA Astrophysics Data System (ADS)

Mirzaei, M.; Ripka, P.; Chirtsov, A.; Kaspar, P.; Vyhnanek, J.

2018-04-01

In this paper, experimental works and theoretical analysis are presented to analyze the influence of the conductor permeability on the precision of yokeless current sensors. The results of finite-element method (FEM) fit well the measured field values around the conductor. Finally we evaluate the difference in magnetic fields distribution around non-magnetic and magnetic conductor. The calculated values show that the permeability of the ferromagnetic conductor significally affects the reading of the electric current sensors even at DC.

Cable for prospecting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lebouc, L.; Marmignon, J.

1983-03-29

A cable for prospecting, said cable including a core of conductor wires surrounded by insulating material and by armour formed by at least one layer of helically wound steel wires. It includes, from its center to its periphery, inside the armour, an axial monofilament made of a polymer that withstands high temperatures, said monofilament forming the insulation of an inner conductor, an outer conductor and a sheath made of a thermoplastic substance that withstands high temperatures, said inner conductor serving a different electrical function than said core of conductor wires.

Temperature profile detector

DOEpatents

Tokarz, Richard D.

1983-01-01

A temperature profile detector shown as a tubular enclosure surrounding an elongated electrical conductor having a plurality of meltable conductive segments surrounding it. Duplicative meltable segments are spaced apart from one another along the length of the enclosure. Electrical insulators surround these elements to confine molten material from the segments in bridging contact between the conductor and a second electrical conductor, which might be the confining tube. The location and rate of growth of the resulting short circuits between the two conductors can be monitored by measuring changes in electrical resistance between terminals at both ends of the two conductors. Additional conductors and separate sets of meltable segments operational at differing temperatures can be monitored simultaneously for measuring different temperature profiles.

Cryogenic vacuumm RF feedthrough device

DOEpatents

Wu, Genfa [Yorktown, VA; Phillips, Harry Lawrence [Hayes, VA

2008-12-30

A cryogenic vacuum rf feedthrough device comprising: 1) a probe for insertion into a particle beam; 2) a coaxial cable comprising an inner conductor and an outer conductor, a dielectric/insulating layer surrounding the inner conductor, the latter being connected to the probe for the transmission of higher mode rf energy from the probe; and 3) a high thermal conductivity stub attached to the coaxial dielectric about and in thermal contact with the inner conductor which high thermal conductivity stub transmits heat generated in the vicinity of the probe efficiently and radially from the area of the probe and inner conductor all while maintaining useful rf transmission line characteristics between the inner and outer coaxial conductors.

Multiwire conductor having greatly increased interwire resistance and method for making same

DOEpatents

Luhman, T.; Suenaga, M.

1982-03-15

An improved multiwire conductor of the type which is mechanically stabilized by a tin based solder filler is described. A solder filled conductor is heated to a temperature above its melting point for a period long enough to allow a substantial amount of copper to be dissolved from the wires comprising the conductor. The copper forms the brittle intermetallic compound Cu/sub 5/Sn/sub 6/ with tin in the solder. After cooling the conductor is flexed causing a random cracking of the solder, and thereby increasing the interwire resistance of the conductor. The subject invention is particularly adapted for use with braided, ribbon-type solder filled superconductors.

Electron launching voltage monitor

DOEpatents

Mendel, Clifford W.; Savage, Mark E.

1992-01-01

An electron launching voltage monitor measures MITL voltage using a relationship between anode electric field and electron current launched from a cathode-mounted perturbation. An electron launching probe extends through and is spaced from the edge of an opening in a first MITL conductor, one end of the launching probe being in the gap between the MITL conductor, the other end being adjacent a first side of the first conductor away from the second conductor. A housing surrounds the launching probe and electrically connects the first side of the first conductor to the other end of the launching probe. A detector detects the current passing through the housing to the launching probe, the detected current being representative of the voltage between the conductors.

Unsplit bipolar pulse forming line

DOEpatents

Rhodes, Mark A [Pleasanton, CA

2011-05-24

A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

Optimization of ITER Nb3Sn CICCs for coupling loss, transverse electromagnetic load and axial thermal contraction

NASA Astrophysics Data System (ADS)

Nijhuis, A.; van Lanen, E. P. A.; Rolando, G.

2012-01-01

The ITER cable-in-conduit conductors (CICCs) are built up from sub-cable bundles, wound in different stages, which are twisted to counter coupling loss caused by time-changing external magnet fields. The selection of the twist pitch lengths has major implications for the performance of the cable in the case of strain-sensitive superconductors, i.e. Nb3Sn, as the electromagnetic and thermal contraction loads are large but also for the heat load from the AC coupling loss. At present, this is a great challenge for the ITER central solenoid (CS) CICCs and the solution presented here could be a breakthrough for not only the ITER CS but also for CICC applications in general. After proposing longer twist pitches in 2006 and successful confirmation by short sample tests later on, the ITER toroidal field (TF) conductor cable pattern was improved accordingly. As the restrictions for coupling loss are more demanding for the CS conductors than for the TF conductors, it was believed that longer pitches would not be applicable for the conductors in the CS coils. In this paper we explain how, with the use of the TEMLOP model and the newly developed models JackPot-ACDC and CORD, the design of a CICC can be improved appreciably, particularly for the CS conductor layout. For the first time a large improvement is predicted not only providing very low sensitivity to electromagnetic load and thermal axial cable stress variations but at the same time much lower AC coupling loss. Reduction of the transverse load and warm-up-cool-down degradation can be reached by applying longer twist pitches in a particular sequence for the sub-stages, offering a large cable transverse stiffness, adequate axial flexibility and maximum allowed lateral strand support. Analysis of short sample (TF conductor) data reveals that increasing the twist pitch can lead to a gain of the effective axial compressive strain of more than 0.3% with practically no degradation from bending. This is probably explained by the distinct difference in mechanical response of the cable during axial contraction for short and long pitches. For short pitches periodic bending in different directions with relatively short wavelength is imposed because of a lack of sufficient lateral restraint of radial pressure. This can lead to high bending strain and eventually buckling. Whereas for cables with long twist pitches, the strands are only able to react as coherent bundles, being tightly supported by the surrounding strands, providing sufficient lateral restraint of radial pressure in combination with enough slippage to avoid single strand bending along detrimental short wavelengths. Experimental evidence of good performance was already provided with the test of the long pitch TFPRO2-OST2, which is still until today, the best ITER-type cable to strand performance ever without any cyclic load (electromagnetic and thermal contraction) degradation. For reduction of the coupling loss, specific choices of the cabling twist sequence are needed to minimize the area of linked strands and bundles that are coupled and form loops with the applied changing magnetic field, instead of simply avoiding longer pitches. In addition we recommend increasing the wrap coverage of the CS conductor from 50% to at least 70%. A larger wrap coverage fraction enhances the overall strand bundle lateral restraint. The long pitch design seems the best solution to optimize the ITER CS conductor within the given restrictions of the present coil design envelope, only allowing marginal changes. The models predict significant improvement against strain sensitivity and substantial decrease of the AC coupling loss in Nb3Sn CICCs, but also for NbTi CICCs minimization of the coupling loss can obviously be achieved. Although the success of long pitches to transverse load degradation was already demonstrated, the prediction of the elegant innovative combination with low coupling loss needs to be validated by a short sample test.

30 CFR 75.804 - Underground high-voltage cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... grounded systems shall be equipped with metallic shields around each power conductor with one or more ground conductors having a total cross sectional area of not less than one-half the power conductor, and with an insulated external conductor not smaller than No. 8 (A.W.G.) or an insulated internal ground...

30 CFR 75.804 - Underground high-voltage cables.

Code of Federal Regulations, 2011 CFR

2011-07-01

... grounded systems shall be equipped with metallic shields around each power conductor with one or more ground conductors having a total cross sectional area of not less than one-half the power conductor, and with an insulated external conductor not smaller than No. 8 (A.W.G.) or an insulated internal ground...

Current sensor

DOEpatents

Yakymyshyn, Christopher Paul; Brubaker, Michael Allen; Yakymyshyn, Pamela Jane

2007-01-16

A current sensor is described that uses a plurality of magnetic field sensors positioned around a current carrying conductor. The sensor can be hinged to allow clamping to a conductor. The current sensor provides high measurement accuracy for both DC and AC currents, and is substantially immune to the effects of temperature, conductor position, nearby current carrying conductors and aging.

46 CFR 111.60-4 - Minimum cable conductor size.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...

46 CFR 111.60-4 - Minimum cable conductor size.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...

46 CFR 111.60-4 - Minimum cable conductor size.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...

Electromagnetic wrap

DOEpatents

Tremblay, Paul L [Idaho Falls, ID; Scott, Jill R [Idaho Falls, ID

2010-09-28

A device and method for altering the line reactance of a transmission line having a transmission line, a first floating conductor and a grounding (shielding) conductor. The first floating conductor is positioned between and electrically insulated from the transmission line and the grounding conductor. A source and a load are connected at opposite ends of the transmission line.

66. DETAIL OF LAUNCH CONDUCTOR AND ASSISTANT LAUNCH CONDUCTOR PANELS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

66. DETAIL OF LAUNCH CONDUCTOR AND ASSISTANT LAUNCH CONDUCTOR PANELS IN CONSOLE LOCATED CENTRALLY IN SLC-3E CONTROL ROOM. FROM LEFT TO RIGHT IN BACKGROUND: LAUNCH OPERATOR, LAUNCH ANALYST, AND FACILITIES PANELS. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

Method of making and structure for monolithic optical circuits

NASA Technical Reports Server (NTRS)

Evanchuk, Vincent L. (Inventor)

1983-01-01

A method for making monolithic optical circuits, with related optical devices as required or desired, on a supporting surface (10) consists of coating the supporting surface with reflecting metal or cladding resin, spreading a layer of liquid radiation senstivie plastic (12) on the surface, exposing the liquid plastic with a mask (14) to cure it in a desired pattern of light conductors (16, 18, 20), washing away the unexposed liquid plastic, and coating the conductors thus formed with reflective metal or cladding resin. The index of refraction for the cladding (22) is selected to be lower than for the conductors so that light in the conductors will be reflected by the interface with the cladding. For multiple level conductors, as where one conductor must cross over another, the process may be repeated to fabricate a bridge with columns (24, 26) of conductors to the next level, and conductor (28) between the columns. For more efficient transfer of energy over the bridge, faces at 45.degree. may be formed to reflect light up and across the bridge.

Progressing in cable-in-conduit for fusion magnets: from ITER to low cost, high performance DEMO

NASA Astrophysics Data System (ADS)

Uglietti, D.; Sedlak, K.; Wesche, R.; Bruzzone, P.; Muzzi, L.; della Corte, A.

2018-05-01

The performance of ITER toroidal field (TF) conductors still have a significant margin for improvement because the effective strain between ‑0.62% and ‑0.95% limits the strands’ critical current between 15% and 45% of the maximum achievable. Prototype Nb3Sn cable-in-conduit conductors have been designed, manufactured and tested in the frame of the EUROfusion DEMO activities. In these conductors the effective strain has shown a clear improvement with respect to the ITER conductors, reaching values between ‑0.55% and ‑0.28%, resulting in a strand critical current which is two to three times higher than in ITER conductors. In terms of the amount of Nb3Sn strand required for the construction of the DEMO TF magnet system, such improvement may lead to a reduction of at least a factor of two with respect to a similar magnet built with ITER type conductors; a further saving of Nb3Sn is possible if graded conductors/windings are employed. In the best case the DEMO TF magnet could require fewer Nb3Sn strands than the ITER one, despite the larger size of DEMO. Moreover high performance conductors could be operated at higher fields than ITER TF conductors, enabling the construction of low cost, compact, high field tokamaks.

Eddy damping effect of additional conductors in superconducting levitation systems

NASA Astrophysics Data System (ADS)

Jiang, Zhao-Fei; Gou, Xiao-Fan

2015-12-01

Passive superconducting levitation systems consisting of a high temperature superconductor (HTSC) and a permanent magnet (PM) have demonstrated several fascinating applications such as the maglev system, flywheel energy storage. Generally, for the HTSC-PM levitation system, the HTSC with higher critical current density Jc can obtain larger magnetic force to make the PM levitate over the HTSC (or suspended below the HTSC), however, the process of the vibration of the levitated PM, provides very limited inherent damping (essentially hysteresis). To improve the dynamic stability of the levitated PM, eddy damping of additional conductors can be considered as the most simple and effective approach. In this article, for the HTSC-PM levitation system with an additional copper damper attached to the HTSC, we numerically and comprehensively investigated the damping coefficient c, damping ratio, Joule heating of the copper damper, and the vibration frequency of the PM as well. Furthermore, we comparatively studied four different arrangements of the copper damper, on the comprehensive analyzed the damping effect, efficiency (defined by c/VCu, in which VCu is the volume of the damper) and Joule heating, and finally presented the most advisable arrangement.

Electrostatic MEMS devices with high reliability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldsmith, Charles L; Auciello, Orlando H; Sumant, Anirudha V

The present invention provides for an electrostatic microelectromechanical (MEMS) device comprising a dielectric layer separating a first conductor and a second conductor. The first conductor is moveable towards the second conductor, when a voltage is applied to the MEMS device. The dielectric layer recovers from dielectric charging failure almost immediately upon removal of the voltage from the MEMS device.

33 CFR 183.430 - Conductors in circuits of less than 50 volts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Conductors in circuits of less... Requirements § 183.430 Conductors in circuits of less than 50 volts. (a) Each conductor in a circuit that has a... Standard 1128. (b) This section does not apply to communication systems; electronic navigation equipment...

33 CFR 183.430 - Conductors in circuits of less than 50 volts.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Conductors in circuits of less... Requirements § 183.430 Conductors in circuits of less than 50 volts. (a) Each conductor in a circuit that has a... Standard 1128. (b) This section does not apply to communication systems; electronic navigation equipment...

33 CFR 183.430 - Conductors in circuits of less than 50 volts.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Conductors in circuits of less... Requirements § 183.430 Conductors in circuits of less than 50 volts. (a) Each conductor in a circuit that has a... Standard 1128. (b) This section does not apply to communication systems; electronic navigation equipment...

33 CFR 183.430 - Conductors in circuits of less than 50 volts.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Conductors in circuits of less... Requirements § 183.430 Conductors in circuits of less than 50 volts. (a) Each conductor in a circuit that has a... Standard 1128. (b) This section does not apply to communication systems; electronic navigation equipment...

33 CFR 183.430 - Conductors in circuits of less than 50 volts.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Conductors in circuits of less... Requirements § 183.430 Conductors in circuits of less than 50 volts. (a) Each conductor in a circuit that has a... Standard 1128. (b) This section does not apply to communication systems; electronic navigation equipment...

Convectively cooled electrical grid structure

DOEpatents

Paterson, J.A.; Koehler, G.W.

1980-11-10

Undesirable distortions of electrical grid conductors from thermal cycling are minimized and related problems such as unwanted thermionic emission and structural failure from overheating are avoided by providing for a flow of fluid coolant within each conductor. The conductors are secured at each end to separate flexible support elements which accommodate to individual longitudinal expansion and contraction of each conductor while resisting lateral displacements, the coolant flow preferably being directed into and out of each conductor through passages in the flexible support elements. The grid may have a modular or divided construction which facilitates manufacture and repairs.

Temperature limited heaters using phase transformation of ferromagnetic material

DOEpatents

Vitek, John Michael [Oak Ridge, TN; Brady, Michael Patrick [Oak Ridge, TN

2009-10-06

Systems, methods, and heaters for treating a subsurface formation are described herein. Systems and methods for making heaters are described herein. At least one heater includes a ferromagnetic conductor and an electrical conductor. The electrical conductor is electrically coupled to the ferromagnetic conductor. The heater provides a first amount of heat at a lower temperature. The heater may provide a second reduced amount of heat when the heater reaches a selected temperature, or enters a selected temperature range, at which the ferromagnetic conductor undergoes a phase transformation.

Liquid level detector

DOEpatents

Tokarz, Richard D.

1982-01-01

A liquid level sensor having a pair of upright conductors spaced by an insulator defining a first high resistance path between the conductors. An electrically conductive path is interposed between the upright conductors at a discrete location at which liquid level is to be measured. It includes a liquid accessible gap of a dimension such that the electrical resistance across the conductor when the gap is filled with the liquid is detectably less than when the gap is emptied. The conductor might also be physically altered by temperature changes to serve also as an indicator of elevated temperature.

High temperature superconducting composite conductor and method for manufacturing the same

DOEpatents

Holesinger, Terry G.; Bingert, John F.

2002-01-01

A high temperature superconducting composite conductor is provided including a high temperature superconducting material surrounded by a noble metal layer, the high temperature superconducting composite conductor characterized as having a fill factor of greater than about 40. Additionally, the conductor can be further characterized as containing multiple cores of high temperature superconducting material surrounded by a noble metal layer, said multiple cores characterized as having substantially uniform geometry in the cross-sectional dimensions. Processes of forming such a high temperature superconducting composite conductor are also provided.

Liquid-level detector

DOEpatents

Not Available

1981-01-29

Aliquid level sensor is described which has a pair of upright conductors spaced by an insulator defining a first high resistance path between the conductors. An electrically conductive path is interposed between the upright conductors at a discrete location at which liquid level is to be measured. It includes a liquid accessible gap of a dimension such that the electrical resistance across the conductor when the gap is filled with the liquid is detectably less than when the gap is emptied. The conductor might also be physically altered by temperature changes to serve also as an indicator of elevated temperature.

Electron launching voltage monitor

DOEpatents

Mendel, C.W.; Savage, M.E.

1992-03-17

An electron launching voltage monitor measures MITL voltage using a relationship between anode electric field and electron current launched from a cathode-mounted perturbation. An electron launching probe extends through and is spaced from the edge of an opening in a first MITL conductor, one end of the launching probe being in the gap between the MITL conductor, the other end being adjacent a first side of the first conductor away from the second conductor. A housing surrounds the launching probe and electrically connects the first side of the first conductor to the other end of the launching probe. A detector detects the current passing through the housing to the launching probe, the detected current being representative of the voltage between the conductors. 5 figs.

75 FR 69165 - Conductor Certification

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-10

...FRA proposes to prescribe regulations for certification of conductors, as required by the Rail Safety Improvement Act of 2008. The proposed rule would require railroads to have a formal program for certifying conductors. As part of that program, railroads would be required to have a formal process for training prospective conductors and determining that all persons are competent before permitting them to serve as a conductor. FRA is proposing this regulation to ensure that only those persons who meet minimum Federal safety standards serve as conductors, to reduce the rate and number of accidents and incidents, and to improve railroad safety. Although this NPRM does not propose any specific amendments to the regulation governing locomotive engineer certification, it does highlight areas in that regulation that may require conforming changes.

Mineral of the month: aluminum

USGS Publications Warehouse

Plunkert, Patricia A.

2005-01-01

Aluminum is the second most abundant metallic element in Earth’s crust after silicon. Even so, it is a comparatively new industrial metal that has been produced in commercial quantities for little more than 100 years. Aluminum is lightweight, ductile, malleable and corrosion resistant, and is a good conductor of heat and electricity. Weighing about one-third as much as steel or copper per unit of volume, aluminum is used more than any other metal except iron. Aluminum can be fabricated into desired forms and shapes by every major metalworking technique to add to its versatility.

Research on the Test of Transmission Line Galloping

NASA Astrophysics Data System (ADS)

Zhang, Lichun; Li, Qing; lv, Zhongbin; Ji, Kunpeng; Liu, Bin

2018-03-01

The load of iced transmission line and the load generated by galloping after the conductor are covered by ice all may cause severe circuit faults, such as tripping, conductor breaking, armor clamp damage and even tower collapse, thus severely threatening running safety of power system. The generation and development processes of galloping of power transmission line is very complicated, and numerous factors may influence the galloping excitation, such as environmental factors, terrain factors and structural parameters of power transmission line; in which, the ice covering of conductor is one of necessary factors causing galloping. Therefore, researches on ice covering increasing test of different types of conductors under different meteorological conditions have been conducted in large-sized multi-functional phytotron, thus obtaining the relation curve of ice covering increasing of conductor along with time under different conditions, and analyzing factors influencing increasing of ice covering. The research result shows that under the same ice covering conditions, the increasing of ice covering of conductor with small diameter is relatively rapid; both environmental temperature and wind speed have obvious influence on increasing of ice covering of conductor, and the environmental temperature will decide the type of ice covering of conductor surface. Meanwhile, after wind tunnel tests targeting conductors with different ice covering shapes, pneumatic stability loss characteristics of conductors with different ice shapes have been obtained. Research results have important scientific reference value for revealing the mechanism of galloping of iced power transmission line, and have relatively high engineering practicability value for promoting realization of early warning system for galloping of iced power transmission line.

Assessment of the noise annoyance among subway train conductors in Tehran, Iran.

PubMed

Hamidi, Mansoureh; Kavousi, Amir; Zaheri, Somayeh; Hamadani, Abolfazl; Mirkazemi, Roksana

2014-01-01

Subway transportation system is a new phenomenon in Iran. Noise annoyance interferes with the individual's task performance, and the required alertness in the driving of subway trains. This is the first study conducted to measure the level of noise and noise annoyance among conductors of subway organization in Tehran, Iran. This cross sectional study was conducted among 167 randomly selected train conductors. Information related to noise annoyance was collected by using a self-administered questionnaire. The dosimetry and sound metering was done for the conductors and inside the cabins. There were 41 sound metering measuring samples inside the conductors' cabin, and there were 12 samples of conductors' noise exposure. The results of sound level meter showed that the mean Leq was 73.0 dBA ± 8.7 dBA and the dosimetry mean measured Leq was 82.1 dBA ± 6.8 dBA. 80% of conductors were very annoyed/annoyed by noise in their work place. 53.9% of conductors reported that noise affected their work performance and 63.5% reported that noise causes that they lose their concentration. The noise related to movement of train wheels on rail was reported as the worst by 83.2% followed by the noise of brakes (74.3%) and the ventilation noise (71.9%). 56.9% of conductors reported that they are suffering from sleeplessness, 40.1% from tinnitus and 80.2% feeling fatigue and sleepy. The study results showed the high level of noise and noise annoyance among train conductors and the poor health outcome of their exposure to this level of noise.

ELECTRON DISCHARGE DEVICE

DOEpatents

Graham, M.H.

1962-09-18

A barrier-grid storage tube and an improved means for writing and reading of information in such a tube are described. A triax cable is provided in the reading and writing circuit and includes a coiled portion. The inner conductor of the cable is connected to the back plate of the barrier grid target assembly of the storage tube, the middle conductor of the cable is connected to a shielding member encompassing the target assembly and this member supports the barrier grid of the assembly, and the outer conductor of the cable is connected to an external shreld surrounding the target assembly. A source of writing sr- gnals is connected between the rnner conductor and middle conductor of said cable. Both the middle and outer conductors are connected to ground at the source end, and a small trimmer condenser is connected between the external shield and the source end of the inner conductor of the cable to compensate for the direct back plate-to-ground capacity due to the imperfect shielding of the barrier grid. The coiled portion of the cable provides for an output signal to a secondary corl coupled thereto. The grounded outer conductor serves as a means for preventing an output signal being applied to the coiled portion of the cable on application of writing signals to the inner and middle conductors of the cable. (AEC)

One-Dimensional Harmonic Model for Biomolecules

PubMed Central

Krizan, John E.

1973-01-01

Following in spirit a paper by Rosen, we propose a one-dimensional harmonic model for biomolecules. Energy bands with gaps of the order of semi-conductor gaps are found. The method is discussed for general symmetric and periodic potential functions. PMID:4709518

Electronic processes in TTF-derived complexes studied by IR spectroscopy

NASA Astrophysics Data System (ADS)

Graja, Andrzej

2001-09-01

We focus our attention on the plasma-edge-like dispersion of the reflectance spectra of the selected bis(ethylenodithio)tetrathiafulvalene (BEDT-TTF)-derived organic conductors. The standard procedure to determine the electron transport parameters in low-dimensional organic conductors consists of fitting the appropriate theoretical models with the experimental reflectance data. This procedure provides us with basic information like plasma frequency, the optical effective mass of charge carriers, their number, mean free path and damping constant. Therefore, it is concluded that the spectroscopy is a powerful tool to study the electronic processes in conducting organic solids.

Variable-Resistivity Material For Memory Circuits

NASA Technical Reports Server (NTRS)

Nagasubramanian, Ganesan; Distefano, Salvador; Moacanin, Jovan

1989-01-01

Nonvolatile memory elements packed densely. Electrically-erasable, programmable, read-only memory matrices made with newly-synthesized organic material of variable electrical resistivity. Material, polypyrrole doped with tetracyanoquinhydrone (TCNQ), changes reversibly between insulating or higher-resistivity state and conducting or low-resistivity state. Thin film of conductive polymer separates layer of row conductors from layer of column conductors. Resistivity of film at each intersection and, therefore, resistance of memory element defined by row and column, increased or decreased by application of suitable switching voltage. Matrix circuits made with this material useful for experiments in associative electronic memories based on models of neural networks.

Electromagnetic Pulse Excitation of Finite-Long Dissipative Conductors over a Conducting Ground Plane in the Time Domain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campione, Salvatore; Warne, Larry K.; Schiek, Richard

2017-09-01

This report details the modeling results for the response of a finite-length dissipative conductor interacting with a conducting ground to a hypothetical nuclear device with the same output energy spectrum as the Fat Man device. We use a time-domain method based on transmission line theory that allows accounting for time-varying air conductivities. We implemented such method in a code we call ATLOG - Analytic Transmission Line Over Ground. Results are compared the frequency-domain version of ATLOG previously developed and to the circuit simulator Xyce in some instances. Intentionally Left Blank

Effects of Conductor Baton Use on Band and Choral Musicians' Perceptions of Conductor Expressivity and Clarity

ERIC Educational Resources Information Center

Nápoles, Jessica; Silvey, Brian A.

2017-01-01

The purpose of this study was to examine participants' (college band and choral musicians, N = 143) perceptions of conductor clarity and expressivity after viewing band and choral directors conducting with or without a baton. One band and one choral conductor each prepared and conducted two excerpts of Guy Forbes's "O Nata Lux", a piece…

High conductivity composite metal

DOEpatents

Zhou, Ruoyi; Smith, James L.; Embury, John David

1998-01-01

Electrical conductors and methods of producing them, where the conductors possess both high strength and high conductivity. Conductors are comprised of carbon steel and a material chosen from a group consisting of copper, nickel, silver, and gold. Diffusion barriers are placed between these two materials. The components of a conductor are assembled and then the assembly is subjected to heat treating and mechanical deformation steps.

Microminiature coaxial cable and methods manufacture

DOEpatents

Bongianni, Wayne L.

1986-01-01

A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 .mu.m thick and from 150 to 200 .mu.m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dielectric. Alternately the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microballoons to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion.

Microminiature coaxial cable and method of manufacture

DOEpatents

Bongianni, W.L.

1989-03-28

A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 [mu]m thick and from 150 to 200 [mu]m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dielectric. Alternately, the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microspheres to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion. 2 figs.

Microminiature coaxial cable and method of manufacture

DOEpatents

Bongianni, Wayne L.

1989-01-01

A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 .mu.m thick and from 150 to 200 .mu.m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dielectric. Alternately, the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microspheres to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion.

Microminiature coaxial cable and methods of manufacture

DOEpatents

Bongianni, W.L.

1983-12-29

A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 ..mu..m thick and from 150 to 200 ..mu..m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dieleectric. Alternately the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microballoons to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion.

Microminiature coaxial cable and methods manufacture

DOEpatents

Bongianni, W.L.

1986-04-08

A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 [mu]m thick and from 150 to 200 [mu]m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dielectric. Alternately the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microballoons to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion. 2 figs.

Superconducting energy storage magnet

NASA Technical Reports Server (NTRS)

Boom, Roger W. (Inventor); Eyssa, Yehia M. (Inventor); Abdelsalam, Mostafa K. (Inventor); Huang, Xianrui (Inventor)

1993-01-01

A superconducting magnet is formed having composite conductors arrayed in coils having turns which lie on a surface defining substantially a frustum of a cone. The conical angle with respect to the central axis is preferably selected such that the magnetic pressure on the coil at the widest portion of the cone is substantially zero. The magnet structure is adapted for use as an energy storage magnet mounted in an earthen trench or tunnel where the strength the surrounding soil is lower at the top of the trench or tunnel than at the bottom. The composite conductor may be formed having a ripple shape to minimize stresses during charge up and discharge and has a shape for each ripple selected such that the conductor undergoes a minimum amount of bending during the charge and discharge cycle. By minimizing bending, the working of the normal conductor in the composite conductor is minimized, thereby reducing the increase in resistance of the normal conductor that occurs over time as the conductor undergoes bending during numerous charge and discharge cycles.

High voltage feedthrough bushing

DOEpatents

Brucker, John P.

1993-01-01

A feedthrough bushing for a high voltage diode provides for using compression sealing for all sealing surfaces. A diode assembly includes a central conductor extending through the bushing and a grading ring assembly circumferentially surrounding and coaxial with the central conductor. A flexible conductive plate extends between and compressively seals against the central conductor and the grading ring assembly, wherein the flexibility of the plate allows inner and outer portions of the plate to axially translate for compression sealing against the central conductor and the grading ring assembly, respectively. The inner portion of the plate is bolted to the central conductor for affecting sealing. A compression beam is also bolted to the central conductor and engages the outer portion of the plate to urge the outer portion toward the grading ring assembly to obtain compression sealing therebetween.

Computational quench model applicable to the SMES/CICC

NASA Astrophysics Data System (ADS)

Luongo, Cesar A.; Chang, Chih-Lien; Partain, Kenneth D.

1994-07-01

A computational quench model accounting for the hydraulic peculiarities of the 200 kA SMES cable-in-conduit conductor has been developed. The model is presented and used to simulate the quench on the SMES-ETM. Conclusions are drawn concerning quench detection and protection. A plan for quench model validation is presented.

Casimir effect for perfect electromagnetic conductors (PEMCs): a sum rule for attractive/repulsive forces

NASA Astrophysics Data System (ADS)

Rode, Stefan; Bennett, Robert; Yoshi Buhmann, Stefan

2018-04-01

We discuss the Casimir effect for boundary conditions involving perfect electromagnetic conductors, which interpolate between perfect electric conductors and perfect magnetic conductors. Based on the corresponding reciprocal Green’s tensor we construct the Green’s tensor for two perfectly reflecting plates with magnetoelectric coupling (non-reciprocal media) within the framework of macroscopic quantum electrodynamics. We calculate the Casimir force between two arbitrary perfect electromagnetic conductor plates, resulting in a universal analytic expression that connects the attractive Casimir force with the repulsive Boyer force. We relate the results to a duality symmetry of electromagnetism.

Conductor requirements for high-temperature superconducting utility power transformers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pleva, E. F.; Mehrotra, V.; Schwenterly, S W

High-temperature superconducting (HTS) coated conductors in utility power transformers must satisfy a set of operating requirements that are driven by two major considerations-HTS transformers must be economically competitive with conventional units, and the conductor must be robust enough to be used in a commercial manufacturing environment. The transformer design and manufacturing process will be described in order to highlight the various requirements that it imposes on the HTS conductor. Spreadsheet estimates of HTS transformer costs allow estimates of the conductor cost required for an HTS transformer to be competitive with a similarly performing conventional unit.

Formation of 2D nanoparticles with block structure in simultaneous electric explosion of conductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kryzhevich, Dmitrij S., E-mail: kryzhev@ispms.ru, E-mail: kost@ispms.ru; Zolnikov, Konstantin P., E-mail: kryzhev@ispms.ru, E-mail: kost@ispms.ru; Abdrashitov, Andrei V.

2014-11-14

A molecular dynamics simulation of nanoparticle formation in simultaneous electric explosion of conductors is performed. Interatomic interaction is described using potentials calculated in the framework of the embedded atom method. High-rate heating results in failure of the conductors with the formation of nanoparticles. The influence of the heating rate, temperature distribution over the specimen cross-section and the distance between simultaneously exploded conductors on the structure of formed nanoparticles is studied. The calculation results show that the electric explosion of conductors allows the formation of nanoparticles with block structure.

Convectively cooled electrical grid structure

DOEpatents

Paterson, James A.; Koehler, Gary W.

1982-01-01

Undesirable distortions of electrical grid conductors (12) from thermal cycling are minimized and related problems such as unwanted thermionic emission and structural failure from overheating are avoided by providing for a flow of fluid coolant within each conductor (12). The conductors (12) are secured at each end to separate flexible support elements (16) which accommodate to individual longitudinal expansion and contraction of each conductor (12) while resisting lateral displacements, the coolant flow preferably being directed into and out of each conductor through passages (48) in the flexible support elements (16). The grid (11) may have a modular or divided construction which facilitates manufacture and repairs.

46 CFR 111.05-37 - Overcurrent devices.

Code of Federal Regulations, 2011 CFR

2011-10-01

... devices. (a) A permanently grounded conductor must not have an overcurrent device unless the overcurrent device simultaneously opens each ungrounded conductor of the circuit. (b) The neutral conductor of the...

77 FR 61657 - Petition for Waiver of Compliance

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-10

.... The railroad now requests a similar waiver from the conductor certification regulations for purposes... encourage conductor reporting of close calls and protect conductors and Amtrak from discipline or sanctions...

46 CFR 111.05-37 - Overcurrent devices.

Code of Federal Regulations, 2010 CFR

2010-10-01

... devices. (a) A permanently grounded conductor must not have an overcurrent device unless the overcurrent device simultaneously opens each ungrounded conductor of the circuit. (b) The neutral conductor of the...

46 CFR 111.15-20 - Conductors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each cable...

46 CFR 111.15-20 - Conductors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each cable...

46 CFR 111.15-20 - Conductors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each cable...

46 CFR 111.15-20 - Conductors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each cable...

46 CFR 111.15-20 - Conductors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each cable...

Topological properties of a self-assembled electrical network via ab initio calculation

NASA Astrophysics Data System (ADS)

Stephenson, C.; Lyon, D.; Hübler, A.

2017-02-01

Interacting electrical conductors self-assemble to form tree like networks in the presence of applied voltages or currents. Experiments have shown that the degree distribution of the steady state networks are identical over a wide range of network sizes. In this work we develop a new model of the self-assembly process starting from the underlying physical interaction between conductors. In agreement with experimental results we find that for steady state networks, our model predicts that the fraction of endpoints is a constant of 0.252, and the fraction of branch points is 0.237. We find that our model predicts that these scaling properties also hold for the network during the approach to the steady state as well. In addition, we also reproduce the experimental distribution of nodes with a given Strahler number for all steady state networks studied.

Super-Joule heating in graphene and silver nanowire network

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maize, Kerry; Das, Suprem R.; Sadeque, Sajia

Transistors, sensors, and transparent conductors based on randomly assembled nanowire networks rely on multi-component percolation for unique and distinctive applications in flexible electronics, biochemical sensing, and solar cells. While conduction models for 1-D and 1-D/2-D networks have been developed, typically assuming linear electronic transport and self-heating, the model has not been validated by direct high-resolution characterization of coupled electronic pathways and thermal response. In this letter, we show the occurrence of nonlinear “super-Joule” self-heating at the transport bottlenecks in networks of silver nanowires and silver nanowire/single layer graphene hybrid using high resolution thermoreflectance (TR) imaging. TR images at the microscopicmore » self-heating hotspots within nanowire network and nanowire/graphene hybrid network devices with submicron spatial resolution are used to infer electrical current pathways. The results encourage a fundamental reevaluation of transport models for network-based percolating conductors.« less

High conductivity composite metal

DOEpatents

Zhou, R.; Smith, J.L.; Embury, J.D.

1998-01-06

Electrical conductors and methods of producing them are disclosed, where the conductors possess both high strength and high conductivity. Conductors are comprised of carbon steel and a material chosen from a group consisting of copper, nickel, silver, and gold. Diffusion barriers are placed between these two materials. The components of a conductor are assembled and then the assembly is subjected to heat treating and mechanical deformation steps. 10 figs.

Detailed characteristics of intermittent current pulses due to positive corona

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Yang, E-mail: liuyangwuh520@sina.com; Cui, Xiang; Lu, Tiebing

In order to get detailed characteristics of intermittent current pulses due to positive corona such as the repetition rate of burst-pulse trains, the peak value ratio of the primary pulse to the secondary pulse, the number of pulses per burst, and the interval of the secondary pulses, a systematic study was carried out in a coaxial conductor-cylinder electrode system with the conductor electrode being set with a discharge point. Empirical formulae for the number of pulses per burst and the interval of the secondary pulses are first presented. A theoretical model based on the motion of the space-charge clouds ismore » proposed. Analysis with the model gives explanations to the experimental results and reveals some new insights into the physical mechanism of positive intermittent corona.« less

30 CFR 75.805 - Couplers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... shall be grounded to the ground conductor in the cable. The coupler shall be constructed so that the ground check continuity conductor shall be broken first and the ground conductors shall be broken last...

Solid-state proton conductors

NASA Astrophysics Data System (ADS)

Jewulski, J. R.; Osif, T. L.; Remick, R. J.

1990-12-01

The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium temperature SSPC development, electrodes for moderate temperature (SSPC) fuel cell, basic material and measurement techniques applicable for SSPC development, modeling, and optimization studies. Correlation and optimization studies are described which include correlation studies on proton conduction and oxide cathode optimization for the SSPC fuel cell. Experiments with the SSPC fuel cells are presented which include the fabrication of the electrolyte disks, apparatus for conducting measurements, the strontium-cerium based electrolyte, the barium-cerium based electrolyte with solid foil electrodes, the barium-cerium based electrolyte with porous electrodes, and conduction mechanisms.

Deep electrical resistivity structure of northwestern Costa Rica

NASA Astrophysics Data System (ADS)

Brasse, H.; Kapinos, G.; Mütschard, L.; Alvarado, G. E.; Worzewski, T.; Jegen, M.

2009-01-01

First long-period magnetotelluric investigations were conducted in early 2008 in northwestern Costa Rica, along a profile that extends from the coast of the Pacific Ocean, traverses the volcanic arc and ends currently at the Nicaraguan border. The aim of this study is to gain insight into the electrical resistivity structure and thus fluid distribution at the continental margin where the Cocos plate subducts beneath the Caribbean plate. Preliminary two-dimensional models map the only moderately resistive mafic/ultramafic complexes of the Nicoya Peninsula (resistivity of a few hundred Ωm), the conductive forearc and the backarc basins (several Ωm). Beneath the backarc basin the data image a poor conductor in the basement with a clear termination in the south, which may tentatively be interpreted as the Santa Elena Suture. The volcanic arc shows no pronounced anomaly at depth, but a moderate conductor underlies the backarc with a possible connection to the upper mantle. A conductor at deep-crustal levels in the forearc may reflect fluid release from the downgoing slab.

A new design of a miniature filter on microstrip resonators with an interdigital structure of conductors

NASA Astrophysics Data System (ADS)

Belyaev, B. A.; Serzhantov, A. M.; Bal'va, Ya. F.; Leksikov, An. A.; Galeev, R. G.

2015-05-01

A microstrip bandpass filter of new design based on original resonators with an interdigital structure of conductors has been studied. The proposed filters of third to sixth order are distinguished for their high frequency-selective properties and much smaller size than analogs. It is established that a broad stop band, extending up to a sixfold central bandpass frequency, is determined by low unloaded Q of higher resonance mode and weak coupling of resonators in the pass band. It is shown for the first time that, as the spacing of interdigital stripe conductors decreases, the Q of higher resonance mode monotonically drops, while the Q value for the first operating mode remains high. A prototype fourth-order filter with a central frequency of 0.9 GHz manufactured on a ceramic substrate with dielectric permittivity ɛ = 80 has microstrip topology dimensions of 9.5 × 4.6 × 1 mm3. The electrodynamic 3D model simulations of the filter characteristics agree well with the results of measurements.

Going full circle: phase-transition thermodynamics of ionic liquids.

PubMed

Preiss, Ulrich; Verevkin, Sergey P; Koslowski, Thorsten; Krossing, Ingo

2011-05-27

We present the full enthalpic phase transition cycle for ionic liquids (ILs) as examples of non-classical salts. The cycle was closed for the lattice, solvation, dissociation, and vaporization enthalpies of 30 different ILs, relying on as much experimental data as was available. High-quality dissociation enthalpies were calculated at the G3 MP2 level. From the cycle, we could establish, for the first time, the lattice and solvation enthalpies of ILs with imidazolium ions. For vaporization, lattice, and dissociation enthalpies, we also developed new prediction methods in the course of our investigations. Here, as only single-ion values need to be calculated and the tedious optimization of an ion pair can be circumvented, the computational time is short. For the vaporization enthalpy, a very simple approach was found, using a surface term and the calculated enthalpic correction to the total gas-phase energy. For the lattice enthalpy, the most important constituent proved to be the calculated conductor-like screening model (COSMO) solvation enthalpy in the ideal electric conductor. A similar model was developed for the dissociation enthalpy. According to our assessment, the typical error of the lattice enthalpy would be 9.4 kJ mol(-1), which is less than half the deviation we get when using the (optimized) Kapustinskii equation or the recent volume-based thermodynamics (VBT) theory. In contrast, the non-optimized VBT formula gives lattice enthalpies 20 to 140 kJ mol(-1) lower than the ones we assessed in the cycle, because of the insufficient description of dispersive interactions. Our findings show that quantum-chemical calculations can greatly improve the VBT approaches, which were parameterized for simple, inorganic salts with ideally point-shaped charges. In conclusion, we suggest the term "augmented VBT", or "aVBT", to describe this kind of theoretical approach. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wind Tunnel Tests on Aerodynamic Characteristics of two types of Iced Conductors with Elastic Support

NASA Astrophysics Data System (ADS)

Yi, You; Cheng, He; Xinxin, Wang

2018-01-01

The wind tunnel tests were carried out to obtain the variation laws of static aerodynamic characteristics of crescent and D-shape iced conductor with different wind velocities, wind attack angles and torsional elastic support stiffness. Test results show that the variation of wind velocity has a relatively large influence on the aerodynamic coefficients of crescent conductor with torsional elastic support 1. However, the influence on that of D-shape conductor is not obvious. With the increase of the torsional elastic support stiffness, the lift and moment coefficient curves of the crescent iced conductor form an obvious peak phenomenon in the range of 0 ° ∼30°. Meanwhile, the wind attack angle position corresponding to the maximum value of the lift and moment coefficients of the D-shape iced conductor appear a backward moving phenomenon.

Resistive foil edge grading for accelerator and other high voltage structures

DOEpatents

Caporaso, George J.; Sampayan, Stephen F.; Sanders, David M.

2014-06-10

In a structure or device having a pair of electrical conductors separated by an insulator across which a voltage is placed, resistive layers are formed around the conductors to force the electric potential within the insulator to distribute more uniformly so as to decrease or eliminate electric field enhancement at the conductor edges. This is done by utilizing the properties of resistive layers to allow the voltage on the electrode to diffuse outwards, reducing the field stress at the conductor edge. Preferably, the resistive layer has a tapered resistivity, with a lower resistivity adjacent to the conductor and a higher resistivity away from the conductor. Generally, a resistive path across the insulator is provided, preferably by providing a resistive region in the bulk of the insulator, with the resistive layer extending over the resistive region.

Progress on the Use of Internal Fins as Barriers to Reduce Magnetization on High Current Density Mono Element Internal Tin Conductors (MEIT)

NASA Astrophysics Data System (ADS)

Zeitlin, Bruce A.; Gregory, Eric; Pyon, Taeyoung; Scanlan, R. M.; Polyanskii, Anatolii A.; Lee, Peter J.

2004-06-01

A number of configurations of a mono element internal tin conductor (MEIT) were fabricated to explore the effect of internal fins on the effective filament size (Deff) and its effect on wire processing. A current density of 2.85 × 109 A/m2 (12 T) was achieved in a high tin, high Nb conductor. Wire lengths as long as 15.8 km at 0.254 mm diameter with breaks averaging 3 per unit length were achieved. Magnetization measurements and Magneto-Optical (MO) images were taken of the finned and non-fin conductor which indicated the fins appeared to be effective. The Deff achieved in the fin conductor was 80 μm compared with an equivalent conductor without a fin of 165 μm.

Magnetic circuit for hall effect plasma accelerator

NASA Technical Reports Server (NTRS)

Manzella, David H. (Inventor); Jacobson, David T. (Inventor); Hofer, Richard (Inventor); Peterson, Peter (Inventor); Jankovsky, Robert S. (Inventor)

2009-01-01

A Hall effect plasma accelerator includes inner and outer electromagnets, circumferentially surrounding the inner electromagnet along a thruster centerline axis and separated therefrom, inner and outer magnetic conductors, in physical connection with their respective inner and outer electromagnets, with the inner magnetic conductor having a mostly circular shape and the outer magnetic conductor having a mostly annular shape, a discharge chamber, located between the inner and outer magnetic conductors, a magnetically conducting back plate, in magnetic contact with the inner and outer magnetic conductors, and a combined anode electrode/gaseous propellant distributor, located at a bottom portion of the discharge chamber. The inner and outer electromagnets, the inner and outer magnetic conductors and the magnetically conducting back plate form a magnetic circuit that produces a magnetic field that is largely axial and radially symmetric with respect to the thruster centerline.

Elastically stretchable thin film conductors on an elastomeric substrate

NASA Astrophysics Data System (ADS)

Jones Harris, Joyelle Elizabeth

Imagine a large, flat screen television that can be rolled into a small cylinder after purchase in the store and then unrolled and mounted onto the wall of a home. The electronic devices within the television must be able to withstand large deformation and tensile strain. Consider a robot that is covered with an electronic skin that simulates human skin. The skin would enable the machine to lift an elderly person with care and sensitivity. The skin will endure repeated deformation with the highest tensile strains being experienced at the robot's joints. These applications and many others will benefit from stretchable electronic circuitry. While several different methods have been employed to create stretchable electronics, all methods use a common tool -- stretchable conductors. Therefore, the goal of this thesis work was to fabricate elastically stretchable conductors that can be used in stretchable electronics. We deposited Au thin films on an elastomeric substrate, and the resulting conductors remained electrically continuous when stretched by 30% and more. We developed photolithographic processes that can be used to pattern elastically stretchable conductors with a 10 mum resolution. We fabricated bi-level stretchable conductors that are separated by an elastomeric insulator and are electrically connected through via holes in the insulator. We applied our bi-level conductors to create a stretchable resistor-inductor-capacitor (RLC) circuit with a tunable resonant frequency. We also used stretchable conductors to measure action potentials in biological samples. This thesis describes the fabrication and application of our elastically stretchable conductors.

Geometries of geoelectrical structures in central Tibetan Plateau from INDEPTH magnetotelluric data

NASA Astrophysics Data System (ADS)

Vozar, J.; Jones, A. G.; Le Pape, F.

2012-12-01

Magnetotelluric (MT) data collected on N-S profiles crossing the Banggong-Nujiang Suture (BNS), which separates the Qiangtang and Lhasa Terranes in central Tibet, as a part of InterNational DEep Profiling of Tibet and the Himalaya project (INDEPTH) are modeled by 2D, 3D inversion codes and 1D petro-physical package LitMod. The modeling exhibits regional resistive and conductive structures correlated with ShuangHu Suture, Tanggula Mountains and strike-slip faults like BengCo-Jiali fault in the south. The BNS is not manifested in the geoelectrical models as a strong crustal regional structure. The strike direction azimuth of mid and lower crustal structures estimated from horizontal slices from 3D modeling (N110°E) is slightly different from one estimated by 2D strike analysis (N100°E). Orientation of crustal structures is perpendicular to convergence direction in this area. The deepest lower crustal conductors are correlated to areas with maximum Moho depth obtained from satellite gravity data. The anisotropic 2D modeling reveals that lower crustal conductor in Lhasa Terrane is anisotropic. This anisotropy can be interpreted as a proof for crustal channel flow below Lhasa Terrane. But same Lhasa lower crust conductor from isotropic 3D modeling can be interpreted more likely as 3D lower Indian crust structure, located to the east from line 500, than geoelectrical anisotropic crustal flow. From deep electromagnetic sounding, supported by independent integrated petro-physical investigation, we can estimate the next upper-mantle conductive layer at depths from 200 km to 250 km below the Lhasa Terrane and less resistive Tibetan lithosphere below the Qiangtang Terrane with conductive upper-mantle in depths about 120 km.

Development of a Novel Hybrid Multi-Junction Architecture for Silicon Solar Cells

DTIC Science & Technology

2015-03-26

W Watts KOH Potassium Hydroxide xj Junction depth k Thermal conductivity z Normal distance l Conductor length σ Stefan...outermost orbit [9]. A material conducts electricity when its valence electrons move into the conduction band and become conductor electrons. Conductor ...become a conductor , it must absorb enough energy to overcome the band gap, which is the energy difference between the valence band and the conduction

Design and Preparation of Two ReBCO-CORC® Cable-In-Conduit Conductors for Fusion and Detector Magnets

NASA Astrophysics Data System (ADS)

Mulder, T.; van der Laan, D.; Weiss, J. D.; Dudarev, A.; Dhallé, M.; ten Kate, H. H. J.

2017-12-01

Two new ReBCO-CORC® based cable-in-conduit conductors (CICC) are developed by CERN in collaboration with ACT-Boulder. Both conductors feature a critical current of about 80 kA at 4.5 K and 12 T. One conductor is designed for operation in large detector magnets, while the other is aimed for application in fusion type magnets. The conductors use a six-around-one cable geometry with six flexible ReBCO CORC® strands twisted around a central tube. The fusion CICC is designed to be cooled by the internal forced flow of either helium gas or supercritical helium to cope with high heat loads in superconducting magnets in large fusion experimental reactors. In addition, the cable is enclosed by a stainless steel jacket to accommodate with the high level of Lorentz forces present in such magnets. Detector type magnets require stable, high-current conductors. Therefore, the detector CORC® CICC comprises an OFHC copper jacket with external conduction cooling, which is advantageous due to its simplicity. A 2.8 m long sample of each conductor is manufactured and prepared for testing in the Sultan facility at PSI Villigen. In the paper, the conductor design and assembly steps for both CORC® CICCs are highlighted.

Investigation of a novel protonic/electronic ceramic composite material as a candidate for hydrogen separation membranes

NASA Astrophysics Data System (ADS)

Fish, Jason S.

A novel ceramic protonic/electronic conductor composite BaCe 0.2Zr0.7Y0.1O3-delta / Sr0.95 Ti0.9Nb0.1O3-delta (BCZY27/STN95: BS27) has been synthesized, and its electrical properties and hydrogen permeability have been investigated. The volume ratio of the STN95 phase was varied from 50 - 70 % to test the effects on conductivity and hydrogen permeability. BCZY27 and STN95 powders were prepared by solid-state reaction, and membrane samples were fabricated through conventional and spark plasma sintering techniques. The phase composition, density, and microstructure were compared between the sintering methodologies. Total conductivities of 0.01 - 0.06 S·cm -1 were obtained in wet (+1 % H2O) dilute H2/(N 2, He, Ar) from 600 - 800 °C for 50 volume % STN95. With increasing STN content (60 and 70 volume %), conductivity generally increased, though remained lower than predicted by standard effective medium models, even at 70 volume % STN95. A new effective medium model was proposed, which accounted for an interfacial resistance term associated with the heterojunctions formed between the BCZY27 and STN95 phases. Better fits for the measured data were achieved with this new method, although some effects remain unexplained. Discrepancies between the model and experiment were attributed to space charge effects, grain boundary resistances, and insulating impurity phase formation during synthesis. Dense BS27 samples were tested for high-temperature hydrogen permeation and a measured flux of 0.006 mumol·cm-2·s -1 was recorded for a 50 volume % STN95 sample at 700 °C, using dry argon as a sweep gas. This value represents a modest improvement on other ceramic composite membranes, but remains short of targets for commercialization. Persistent leaks in the flux experiments generated a shallower hydrogen gradient across the samples, although this p(H2) on the sweep side simultaneously decreased the oxygen partial pressure gradient across the sample and preserved the reduced state of the membrane. The addition of thin palladium layers (100 nm) to another 50 volume % STN95 sample increased the flux five-fold to 0.026 mumol·cm-2·s -1 at 700 °C. Experiments on 60 and 70 volume % STN95 samples revealed no measurable hydrogen flux, which was attributed to the proton-conducting BCZY27 phase being non-percolating for these compositions.

Materials and methods for autonomous restoration of electrical conductivity

DOEpatents

Blaiszik, Benjamin J; Odom, Susan A; Caruso, Mary M; Jackson, Aaron C; Baginska, Marta B; Ritchey, Joshua A; Finke, Aaron D; White, Scott R; Moore, Jeffrey S; Sottos, Nancy R; Braun, Paul V; Amine, Khalil

2014-03-25

An autonomic conductivity restoration system includes a solid conductor and a plurality of particles. The particles include a conductive fluid, a plurality of conductive microparticles, and/or a conductive material forming agent. The solid conductor has a first end, a second end, and a first conductivity between the first and second ends. When a crack forms between the first and second ends of the conductor, the contents of at least a portion of the particles are released into the crack. The cracked conductor and the released contents of the particles form a restored conductor having a second conductivity, which may be at least 90% of the first conductivity.

RADIO FREQUENCY ATTENUATOR

DOEpatents

Giordano, S.

1963-11-12

A high peak power level r-f attenuator that is readily and easily insertable along a coaxial cable having an inner conductor and an outer annular conductor without breaking the ends thereof is presented. Spaced first and second flares in the outer conductor face each other with a slidable cylindrical outer conductor portion therebetween. Dielectric means, such as water, contact the cable between the flares to attenuate the radio-frequency energy received thereby. The cylindrical outer conductor portion is slidable to adjust the voltage standing wave ratio to a low level, and one of the flares is slidable to adjust the attenuation level. An integral dielectric container is also provided. (AFC)

78 FR 25347 - Petition for Amending Waiver of Compliance

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-30

... regulations contained at 49 CFR Part 242, Conductor Certification, in Docket Number FRA-2012-0054. On January... of 49 CFR 242.403 to encourage conductor reporting of close calls, and to protect conductors and...

Is a family-centred initiative a family-centred service? A case of a Conductive Education setting for children with cerebral palsy.

PubMed

Schenker, R; Parush, S; Rosenbaum, P; Rigbi, A; Yochman, A

2016-11-01

From the moment a child is diagnosed as having cerebral palsy, families have to cope on a daily basis with the multifaceted challenges of life-long disability management. Family-centred service is embraced as a 'best practice' model because of accumulating evidence supporting its positive influence on parents and children's outcomes. Nevertheless, research comparing parent and provider perspectives on family-centred practices of educational service providers in education settings is scarce. The aims of this study were to compare the extent to which parents and conductors experience the service delivery in Tsad Kadima, the Association for Conductive Education in Israel, as being family-centred, as well as comparing parents' perception of different educational settings as being family-centred. Measurements of family-centeredness, the Israeli Measure of Processes of Care for families (MPOC-20) and for service providers (MPOC-SP), were administrated to 38 teacher conductors and 83 families of children with cerebral palsy (aged 1-14), from different conductive educational settings. Parents and conductors perceive Conductive Education service as being highly family centred in most domains, rating respectful and supportive care the highest and providing general information the lowest, thus indicating an area where improvements should be made. Parents perceived the service they receive to be more family-centred than conductor's perception about their own activities. In addition, educational setting (day care, pre-school and school) was found to be associated with parent's scores. The current study, which is the first to examine family-centred service provision in a conductive special education setting, from the perspectives of both parents and conductors, provides significant evidence for high-quality services in these settings. © 2016 John Wiley & Sons Ltd.

Fatigue tests of YBCO coated conductors

NASA Astrophysics Data System (ADS)

Bamba, S.; Tanaka, Y.; Ando, T.; Ueda, H.; Ishiyama, A.; Yamada, Y.; Shiohara, Y.

2008-02-01

In this paper, we report the fatigue characteristics of IBAD/PLD YBCO coated conductors. A YBCO coated conductor used in the superconducting coil of a SMES system is repeatedly subjected to mechanical tensile or compressive strain due to the Lorentz force during electrical charging or discharging. The superconducting characteristic of this conductor may deteriorate because of this cyclic strain. Therefore, it is necessary to investigate the effect of cyclic strain on the superconducting characteristics of YBCO coated conductors that have a laminated structure. We developed an experimental apparatus with a U-shaped sample holder in order to apply cyclic strain to the sample tape. This apparatus was used to perform the fatigue tests on YBCO coated conductors in liquid nitrogen in the absence of an external magnetic field. The strain cycles with the maximum strain epsilonmax (zero external strain → epsilonmax → zero external strain) were applied and repeated up to 5000 times, and the Ic measurements were performed at epsilonmax. Therefore, the application of cyclic strain with epsilonmax ranging from 0.3% to 0.5% did not result in any significant deterioration of the superconducting characteristics of the conductor.

Electro-optic component mounting device

DOEpatents

Gruchalla, M.E.

1994-09-13

A technique is provided for integrally mounting a device such as an electro-optic device in a transmission line to avoid series resonant effects. A center conductor of the transmission line has an aperture formed therein for receiving the device. The aperture splits the center conductor into two parallel sections on opposite sides of the device. For a waveguide application, the center conductor is surrounded by a conductive ground surface which is spaced apart from the center conductor with a dielectric material. One set of electrodes formed on the surface of the electro-optic device is directly connected to the center conductor and an electrode formed on the surface of the electro-optic device is directly connected to the conductive ground surface. The electrodes formed on the surface of the electro-optic device are formed on curved sections of the surface of the device to mate with correspondingly shaped electrodes on the conductor and ground surface to provide a uniform electric field across the electro-optic device. The center conductor includes a passage formed therein for passage of optical signals to an electro-optic device. 10 figs.

Patterns of motor recruitment can be determined using surface EMG.

PubMed

Wakeling, James M

2009-04-01

Previous studies have reported how different populations of motor units (MUs) can be recruited during dynamic and locomotor tasks. It was hypothesised that the higher-threshold units would contribute higher-frequency components to the sEMG spectra due to their faster conduction velocities, and thus recruitment patterns that increase the proportion of high-threshold units active would lead to higher-frequency elements in the sEMG spectra. This idea was tested by using a model of varying recruitment coupled to a three-layer volume conductor model to generate a series of sEMG signals. The recruitment varied from (A) orderly recruitment where the lowest-threshold MUs were initially activated and higher-threshold MUs were sequentially recruited as the contraction progressed, (B) a recurrent inhibition model that started with orderly recruitment, but as the higher-threshold units were activated they inhibited the lower-threshold MUs (C) nine models with intermediate properties that were graded between these two extremes. The sEMG was processed using wavelet analysis and the spectral properties quantified by their mean frequency, and an angle theta that was determined from the principal components of the spectra. Recruitment strategies that resulted in a greater proportion of faster MUs being active had a significantly lower theta and higher mean frequency.

Rotation analysis on large complex superconducting cables based on numerical modeling and experiments

NASA Astrophysics Data System (ADS)

Qin, Jinggang; Yue, Donghua; Zhang, Xingyi; Wu, Yu; Liu, Xiaochuan; Liu, Huajun; Jin, Huan; Dai, Chao; Nijhuis, Arend; Zhou, Chao; Devred, Arnaud

2018-07-01

The conductors used in large fusion reactors, e.g. ITER, CFETR and DEMO, are made of cable-in-conduit conductor (CICC) with large diameters up to about 50 mm. The superconducting and copper strands are cabled around a central spiral and then wrapped with stainless-steel tape of 0.1 mm thickness. The cable is then inserted into a jacket under tensile force that increases with the length of insertion. Because the cables are long and with a large diameter, the insertion force could reach values of about 40 kN. The large tensile force could lead to significant rotation forces. This may lead to an increase of the twist pitch, especially for the final one. Understanding the twist pitch variation is very important; in particular, the twist pitch of a cable inside a CICC strongly affects its properties, especially for Nb3Sn conductors. In this paper, a simplified numerical model was used to analyze the cable rotation, including material properties, cabling tension as well as wrap tension. Several rotation experiments with tensile force have been performed to verify the numerical results for CFETR CSMC cables. The results show that the numerical analysis is consistent with the experiments and provides the optimal cabling conditions for large superconducting cables.

Collapse and pull - down analysis of high voltage electricity transmission towers subjected to cyclonic wind

NASA Astrophysics Data System (ADS)

Ahmed, Ammar; Arthur, Craig; Edwards, Mark

2010-06-01

Bulk electricity transmission lines are linear assets that can be very exposed to wind effects, particularly where they traverse steep topography or open coastal terrain in cyclonic regions. Interconnected nature of the lattice type towers and conductors also, present complex vulnerabilities. These relate to the direction of wind attack to the conductors and the cascading failure mechanisms in which the failure of a single tower has cascading effects on neighbouring towers. Such behaviour is exacerbated by the finely tuned nature of tower design which serves to minimize cost and reserve strength at design wind speeds. There is a clear need to better quantify the interdependent vulnerabilities of these critical infrastructure assets in the context of the severe wind hazard. This paper presents a novel methodology developed for the Critical Infrastructure Protection Modelling and Analysis (CIPMA) capability for assessing local wind speeds and the likelihood of tower failure for a range of transmission tower and conductor types. CIPMA is a program managed by the Federal Attorney-General's Department and Geoscience Australia is leading the technical development. The methodology then involves the development of heuristically derived vulnerability models that are consistent with Australian industry experience and full-scale static tower testing results, considering isolated tower loss along with three interdependent failure mechanisms to give overall likelihoods of failure.

Application and experimental validation of an integral method for simulation of gradient-induced eddy currents on conducting surfaces during magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Harris, C. T.; Haw, D. W.; Handler, W. B.; Chronik, B. A.

2013-06-01

The time-varying magnetic fields created by the gradient coils in magnetic resonance imaging can produce negative effects on image quality and the system itself. Additionally, they can be a limiting factor to the introduction of non-MR devices such as cardiac pacemakers, orthopedic implants, and surgical robotics. The ability to model the induced currents produced by the switching gradient fields is key to developing methods for reducing these unwanted interactions. In this work, a framework for the calculation of induced currents on conducting surface geometries is summarized. This procedure is then compared to two separate experiments: (1) the analysis of the decay of currents induced upon a conducting cylinder by an insert gradient set within a head only 7 T MR scanner; and (2) analysis of the heat deposited into a small conductor by a uniform switching magnetic field at multiple frequencies and two distinct conductor thicknesses. The method was shown to allow the accurate modeling of the induced time-varying field decay in the first case, and was able to provide accurate estimation of the rise in temperature in the second experiment to within 30% when the skin depth was greater than or equal to the thickness of the conductor.

Neural network method for lossless two-conductor transmission line equations based on the IELM algorithm

NASA Astrophysics Data System (ADS)

Yang, Yunlei; Hou, Muzhou; Luo, Jianshu; Liu, Taohua

2018-06-01

With the increasing demands for vast amounts of data and high-speed signal transmission, the use of multi-conductor transmission lines is becoming more common. The impact of transmission lines on signal transmission is thus a key issue affecting the performance of high-speed digital systems. To solve the problem of lossless two-conductor transmission line equations (LTTLEs), a neural network model and algorithm are explored in this paper. By selecting the product of two triangular basis functions as the activation function of hidden layer neurons, we can guarantee the separation of time, space, and phase orthogonality. By adding the initial condition to the neural network, an improved extreme learning machine (IELM) algorithm for solving the network weight is obtained. This is different to the traditional method for converting the initial condition into the iterative constraint condition. Calculation software for solving the LTTLEs based on the IELM algorithm is developed. Numerical experiments show that the results are consistent with those of the traditional method. The proposed neural network algorithm can find the terminal voltage of the transmission line and also the voltage of any observation point. It is possible to calculate the value at any given point by using the neural network model to solve the transmission line equation.

46 CFR 169.672 - Wiring for power and lighting circuits.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Wiring for power and lighting circuits must have copper conductors, of 14 AWG or larger, and— (1) Meet... must have stranded conductors. (c) Conductors must be sized so that— (1) They are adequate for the...

Method and system for evaluating integrity of adherence of a conductor bond to a mating surface of a substrate

DOEpatents

Telschow, K.L.; Siu, B.K.

1996-07-09

A method of evaluating integrity of adherence of a conductor bond to a substrate includes: (a) impinging a plurality of light sources onto a substrate; (b) detecting optical reflective signatures emanating from the substrate from the impinged light; (c) determining location of a selected conductor bond on the substrate from the detected reflective signatures; (d) determining a target site on the selected conductor bond from the detected reflective signatures; (e) optically imparting an elastic wave at the target site through the selected conductor bond and into the substrate; (f) optically detecting an elastic wave signature emanating from the substrate resulting from the optically imparting step; and (g) determining integrity of adherence of the selected conductor bond to the substrate from the detected elastic wave signature emanating from the substrate. A system is disclosed which is capable of conducting the method. 13 figs.

Method and system for evaluating integrity of adherence of a conductor bond to a mating surface of a substrate

DOEpatents

Telschow, Kenneth L.; Siu, Bernard K.

1996-01-01

A method of evaluating integrity of adherence of a conductor bond to a substrate includes: a) impinging a plurality of light sources onto a substrate; b) detecting optical reflective signatures emanating from the substrate from the impinged light; c) determining location of a selected conductor bond on the substrate from the detected reflective signatures; d) determining a target site on the selected conductor bond from the detected reflective signatures; e) optically imparting an elastic wave at the target site through the selected conductor bond and into the substrate; f) optically detecting an elastic wave signature emanating from the substrate resulting from the optically imparting step; and g) determining integrity of adherence of the selected conductor bond to the substrate from the detected elastic wave signature emanating from the substrate. A system is disclosed which is capable of conducting the method.

Carbon Nanotube Based Light Sensor

NASA Technical Reports Server (NTRS)

Wincheski, russell A. (Inventor); Smits, Jan M. (Inventor); Jordan, Jeffrey D. (Inventor); Watkins, Anthony Neal (Inventor); Ingram, JoAnne L. (Inventor)

2006-01-01

A light sensor substrate comprises a base made from a semi-conductive material and topped with a layer of an electrically non-conductive material. A first electrode and a plurality of carbon nanotube (CNT)-based conductors are positioned on the layer of electrically non-conductive material with the CNT-based conductors being distributed in a spaced apart fashion about a periphery of the first electrode. Each CNT-based conductor is coupled on one end thereof to the first electrode and extends away from the first electrode to terminate at a second free end. A second or gate electrode is positioned on the non-conductive material layer and is spaced apart from the second free end of each CNT-based conductor. Coupled to the first and second electrode is a device for detecting electron transfer along the CNT-based conductors resulting from light impinging on the CNT-based conductors.

Downhole transmission system comprising a coaxial capacitor

DOEpatents

Hall, David R [Provo, UT; Pixton, David S [Lehi, UT; Johnson, Monte L [Orem, UT; Bartholomew, David B [Springville, UT; Hall, Jr., H. Tracy; Rawle, Michael [Springville, UT

2011-05-24

A transmission system in a downhole component comprises a plurality of data transmission elements. A coaxial cable having an inner conductor and an outer conductor is disposed within a passage in the downhole component such that at least one capacitor is disposed in the passage and having a first terminal coupled to the inner conductor and a second terminal coupled to the outer conductor. Preferably the transmission element comprises an electrically conducting coil. Preferably, within the passage a connector is adapted to electrically connect the inner conductor of the coaxial cable and the lead wire. The coaxial capacitor may be disposed between and in electrically communication with the connector and the passage. In another embodiment a connector is adapted to electrical connect a first and a second portion of the inner conductor of the coaxial cable and a coaxial capacitor is in electrical communication with the connector and the passage.

Decoupled Ion Transport in a Protein-Based Solid Ion Conductor.

PubMed

Fu, Xuewei; Jewel, Yead; Wang, Yu; Liu, Jin; Zhong, Wei-Hong

2016-11-03

Simultaneous achievement of good electrochemical and mechanical properties is crucial for practical applications of solid ion conductors. Conventional polymer conductors suffer from low conductivity, low transference number, and deteriorated mechanical properties with the enhancement of conductivity, resulting from the coupling between ion transport and polymer movement. Here we present a successful fabrication and fundamental understanding of a high performance soy protein-based solid conductor. The conductor shows ionic conductivity of ∼10 -5 S/cm, transference number of 0.94, and modulus of 1 GPa at room temperature, and still remains flexible and easily processable. Molecular simulations indicate that this is due to appropriate manipulation of the protein structures for effective exploitation of protein functional groups. A decoupled transport mechanism, which is able to explain all results, is proposed. The new insights can be utilized to provide guidelines for design, optimization, and fabrication of high performance biosolid conductors.

Parametric analysis of hollow conductor parallel and coaxial transmission lines for high frequency space power distribution

NASA Technical Reports Server (NTRS)

Jeffries, K. S.; Renz, D. D.

1984-01-01

A parametric analysis was performed of transmission cables for transmitting electrical power at high voltage (up to 1000 V) and high frequency (10 to 30 kHz) for high power (100 kW or more) space missions. Large diameter (5 to 30 mm) hollow conductors were considered in closely spaced coaxial configurations and in parallel lines. Formulas were derived to calculate inductance and resistance for these conductors. Curves of cable conductance, mass, inductance, capacitance, resistance, power loss, and temperature were plotted for various conductor diameters, conductor thickness, and alternating current frequencies. An example 5 mm diameter coaxial cable with 0.5 mm conductor thickness was calculated to transmit 100 kW at 1000 Vac, 50 m with a power loss of 1900 W, an inductance of 1.45 micron and a capacitance of 0.07 micron-F. The computer programs written for this analysis are listed in the appendix.

System, method and computer-readable medium for locating physical phenomena

DOEpatents

Weseman, Matthew T [Idaho Falls, ID; Rohrbaugh, David T [Idaho Falls, ID; Richardson, John G [Idaho Falls, ID

2008-02-26

A method, system and computer product for detecting the location of a deformation of a structure includes baselining a defined energy transmitting characteristic for each of the plurality of laterally adjacent conductors attached to the structure. Each of the plurality of conductors includes a plurality of segments coupled in series and having an associated unit value representative of the defined energy transmitting characteristic. The plurality of laterally adjacent conductors includes a plurality of identity groups with each identity group including at least one of the plurality of segments from each of the plurality of conductors. Each of the plurality of conductors are monitored for a difference in the defined energy transmitting characteristic when compared with a baseline energy transmitting characteristic for each of the plurality of conductors. When the difference exceeds a threshold value, a location of the deformation along the structure is calculated.

Downhole tool adapted for telemetry

DOEpatents

Hall, David R.; Fox, Joe

2010-12-14

A cycleable downhole tool such as a Jar, a hydraulic hammer, and a shock absorber adapted for telemetry. This invention applies to other tools where the active components of the tool are displaced when the tool is rotationally or translationally cycled. The invention consists of inductive or contact transmission rings that are connected by an extensible conductor. The extensible conductor permits the transmission of the signal before, after, and during the cycling of the tool. The signal may be continuous or intermittent during cycling. The invention also applies to downhole tools that do not cycle, but in operation are under such stress that an extensible conductor is beneficial. The extensible conductor may also consist of an extensible portion and a fixed portion. The extensible conductor also features clamps that maintain the conductor under stresses greater than that seen by the tool, and seals that are capable of protecting against downhole pressure and contamination.

Load-resistant coaxial transmission line

DOEpatents

Hall, David R.; Fox, Joe

2006-01-03

A transmission line for downhole tools that make up all or part of a tool string for drilling and production of oil, gas, and geothermal wells that can withstand the dynamic gravitational forces and other accelerations associated with downhole excavations. The transmission line has a metal tube, or outer conductor, that houses a coaxial wire inner conductor. A non-metallic dielectric material is interposed between the inner and outer conductors. The outer and inner conductors and the dielectric are sufficiently compressed together so that independent motion between them is abated. Compression of the components of the transmission line may be achieved by drawing the transmission through one or more dies in order to draw down the outer conductor onto the dielectric, or by expanding the inner conductor against the dielectric using a mandrel or hydraulic pressure. Non-metallic bead segments may be used in aid of the compression necessary to resist the dynamic forces and accelerations of drilling.

Analysis of waveguides containing EMCs (electromagnetic conductors) or PEMCs (perfect electromagnetic conductors)

NASA Astrophysics Data System (ADS)

Prudêncio, Filipa R.; Matos, Sérgio A.; Paiva, Carlos R.

2014-11-01

The concept of a perfect electromagnetic conductor (PEMC) was introduced to generalize and unify two well-known and apparently disjoint concepts in electromagnetics: the perfect electric conductor (PEC) and the perfect magnetic conductor (PMC). Although the PEMC has proven a fertile tool in electromagnetic analyses dealing with new and complex boundaries, its corresponding definition as a medium has, nevertheless, raised several problems. In fact, according to its initial 3D definition, the PEMC cannot be considered a unique and well-defined medium: it leads to extraneous fields without physical meaning. By using a previously published generalization of a PEMC that regards this concept both as a boundary and as a medium - which was dubbed an MIM (Minkowskian isotropic medium) and acts, in practice, as an actual electromagnetic conductor (EMC) - it is herein presented a straightforward analysis of waveguides containing PEMCs that readily and systematically follows from the general framework of waveguides containing EMCs.

FEMCAM Analysis of SULTAN Test Results for ITER Nb3SN Cable-conduit Conductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuhu Zhai, Pierluigi Bruzzone, Ciro Calzolaio

2013-03-19

Performance degradation due to filament fracture of Nb3 Sn cable-in-conduit conductors (CICCs) is a critical issue in large-scale magnet designs such as ITER which is currently being constructed in the South of France. The critical current observed in most SULTAN TF CICC samples is significantly lower than expected and the voltage-current characteristic is seen to have a much broader transition from a single strand to the CICC. Moreover, most conductors exhibit the irreversible degradation due to filament fracture and strain relaxation under electromagnetic cyclic loading. With recent success in monitoring thermal strain distribution and its evolution under the electromagnetic cyclicmore » loading from in situ measurement of critical temperature, we apply FEMCAM which includes strand filament breakage and local current sharing effects to SULTAN tested CICCs to study Nb3 Sn strain sensitivity and irreversible performance degradation. FEMCAM combines the thermal bending effect during cool down and the EM bending effect due to locally accumulating Lorentz force during magnet operation. It also includes strand filament fracture and related local current sharing for the calculation of cable n value. In this paper, we model continuous performance degradation under EM cyclic loading based on strain relaxation and the transition broadening upon cyclic loading to the extreme cases seen in SULTAN test data to better quantify conductor performance degradation.« less

46 CFR 120.370 - General grounding requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... hull must not carry current as a conductor except for the following systems: (1) Impressed current... grounding pole and a grounding conductor in the portable cord. (c) Each nonmetallic mast and top mast must have a lightning ground conductor. ...

46 CFR 120.370 - General grounding requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... hull must not carry current as a conductor except for the following systems: (1) Impressed current... grounding pole and a grounding conductor in the portable cord. (c) Each nonmetallic mast and top mast must have a lightning ground conductor. ...

Stators with improved conductor assembly and method of making same

DOEpatents

Dang, Dang Dinh; Blissenbach, Rolf; Schauer, David; Wattleworth, John; Milani, Michael; Hatch, Erik

2013-07-30

A stator includes a stator core, a plurality of slots, and a conductor. The plurality of slots are formed within the stator core. The conductor is disposed continuously within at least two of the plurality of openings.

46 CFR 120.370 - General grounding requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... hull must not carry current as a conductor except for the following systems: (1) Impressed current... grounding pole and a grounding conductor in the portable cord. (c) Each nonmetallic mast and top mast must have a lightning ground conductor. ...

46 CFR 120.370 - General grounding requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... hull must not carry current as a conductor except for the following systems: (1) Impressed current... grounding pole and a grounding conductor in the portable cord. (c) Each nonmetallic mast and top mast must have a lightning ground conductor. ...

46 CFR 120.370 - General grounding requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... hull must not carry current as a conductor except for the following systems: (1) Impressed current... grounding pole and a grounding conductor in the portable cord. (c) Each nonmetallic mast and top mast must have a lightning ground conductor. ...

One-Step Fabrication of Stretchable Copper Nanowire Conductors by a Fast Photonic Sintering Technique and Its Application in Wearable Devices.

PubMed

Ding, Su; Jiu, Jinting; Gao, Yue; Tian, Yanhong; Araki, Teppei; Sugahara, Tohru; Nagao, Shijo; Nogi, Masaya; Koga, Hirotaka; Suganuma, Katsuaki; Uchida, Hiroshi

2016-03-09

Copper nanowire (CuNW) conductors have been considered to have a promising perspective in the area of stretchable electronics due to the low price and high conductivity. However, the fabrication of CuNW conductors suffers from harsh conditions, such as high temperature, reducing atmosphere, and time-consuming transfer step. Here, a simple and rapid one-step photonic sintering technique was developed to fabricate stretchable CuNW conductors on polyurethane (PU) at room temperature in air environment. It was observed that CuNWs were instantaneously deoxidized, welded and simultaneously embedded into the soft surface of PU through the one-step photonic sintering technique, after which highly conductive network and strong adhesion between CuNWs and PU substrates were achieved. The CuNW/PU conductor with sheet resistance of 22.1 Ohm/sq and transmittance of 78% was achieved by the one-step photonic sintering technique within only 20 μs in air. Besides, the CuNW/PU conductor could remain a low sheet resistance even after 1000 cycles of stretching/releasing under 10% strain. Two flexible electronic devices, wearable sensor and glove-shaped heater, were fabricated using the stretchable CuNW/PU conductor, demonstrating that our CuNW/PU conductor could be integrated into various wearable electronic devices for applications in food, clothes, and medical supplies fields.

33 CFR 183.402 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... limited to, conductors, solenoids, motors, generators, alternators, distributors, resistors, appliances and electrical control devices. Pigtails means external power conductors or wires that are part of..., molded plastic, or flexible tubing, around one or more insulated conductors. [CGD 73-217, 42 FR 5944, Jan...

33 CFR 183.402 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... limited to, conductors, solenoids, motors, generators, alternators, distributors, resistors, appliances and electrical control devices. Pigtails means external power conductors or wires that are part of..., molded plastic, or flexible tubing, around one or more insulated conductors. [CGD 73-217, 42 FR 5944, Jan...

High-temperature flat-conductor cable

NASA Technical Reports Server (NTRS)

Rigling, W. S.

1976-01-01

Temperature limit of 25-conductor signal cable and 3-conductor power cable, fabricated using woven and roll laminated technique, increased from 200 C to 350 C when polyimide/fluorinated ethylene propylene or polytetrafluoroethylene insulation films and fluorinated ethylene propylene as adhesive medium is applied.

Task Analysis for the Jobs of Freight Train Conductor and Brakeman

DOT National Transportation Integrated Search

1975-05-31

This document describes the results of a research effort undertaken to detail the tasks of freight train conductors and brakemen. Included with text are detailed operational sequence diagrams for both conductor and brakeman. This task : analysis is s...

Thunderclouds and Lightning Conductors

ERIC Educational Resources Information Center

Martin, P. F.

1973-01-01

Discusses the historical background of the development of lightning conductors, describes the nature of thunderclouds and the lightning flash, and provides a calculation of the electric field under a thundercloud. Also discussed are point discharge currents and the attraction theory of the lightning conductor. (JR)

33 CFR 183.425 - Conductors: General.

Code of Federal Regulations, 2013 CFR

2013-07-01

... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

33 CFR 183.425 - Conductors: General.

Code of Federal Regulations, 2012 CFR

2012-07-01

... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

33 CFR 183.425 - Conductors: General.

Code of Federal Regulations, 2011 CFR

2011-07-01

... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

33 CFR 183.425 - Conductors: General.

Code of Federal Regulations, 2010 CFR

2010-07-01

... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

33 CFR 183.425 - Conductors: General.

Code of Federal Regulations, 2014 CFR

2014-07-01

... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

Aging Wire Insulation Assessment by Phase Spectrum Examination of Ultrasonic Guided Waves

NASA Technical Reports Server (NTRS)

Anastasi, Robert F.; Madaras, Eric I.

2003-01-01

Wire integrity has become an area of concern to the aerospace community including DoD, NASA, FAA, and Industry. Over time and changing environmental conditions, wire insulation can become brittle and crack. The cracks expose the wire conductor and can be a source of equipment failure, short circuits, smoke, and fire. The technique of using the ultrasonic phase spectrum to extract material properties of the insulation is being examined. Ultrasonic guided waves will propagate in both the wire conductor and insulation. Assuming the condition of the conductor remains constant then the stiffness of the insulator can be determined by measuring the ultrasonic guided wave velocity. In the phase spectrum method the guided wave velocity is obtained by transforming the time base waveform to the frequency domain and taking the phase difference between two waveforms. The result can then be correlated with a database, derived by numerical model calculations, to extract material properties of the wire insulator. Initial laboratory tests were performed on a simple model consisting of a solid cylinder and then a solid cylinder with a polymer coating. For each sample the flexural mode waveform was identified. That waveform was then transformed to the frequency domain and a phase spectrum was calculated from a pair of waveforms. Experimental results on the simple model compared well to numerical calculations. Further tests were conducted on aircraft or mil-spec wire samples, to see if changes in wire insulation stiffness can be extracted using the phase spectrum technique.

High voltage capability electrical coils insulated with materials containing SF.sub.6 gas

DOEpatents

Lanoue, Thomas J.; Zeise, Clarence L.; Wagenaar, Loren; Westervelt, Dean C.

1988-01-01

A coil is made having a plurality of layers of adjacent metal conductor windings subject to voltage stress, where the windings have insulation therebetween containing a small number of minute disposed throughout its cross-section, where the voids are voids filled with SF.sub.6 gas to substitute for air or other gaseous materials in from about 60% to about 95% of the cross-sectional void volume in the insulation, thus incorporating an amount of SF.sub.6 gas in the cross-section of the insulation effective to substantially increase corona inception voltages.

Overhead electric power transmission line jumpering system for bundles of five or more subconductors

DOEpatents

Winkelman, Paul F.

1982-01-01

Jumpering of electric power transmission lines at a dead end tower. Two transmission line conductor bundles each contain five or more spaced apart subconductors (5) arranged in the shape of a cylinder having a circular cross section. The ends of each bundle of subconductors are attached with insulators to a dead end tower (1). Jumpering allows the electric current to flow between the two bundles of subconductors using jumper buses, internal jumper conductors, and external jumper conductors. One or more current collecting jumper buses (37) are located inside each bundle of subconductors with each jumper bus being attached to the end of a subconductor. Small-diameter internal jumper conductors (33) are located in the inherently electrically shielded area inside each bundle of subconductors with each subconductor (except ones having an attached jumper bus) having one internal jumper conductor connected between that subconductor's end and a jumper bus. Large-diameter external jumper conductors (9) are located outside each bundle of subconductors with one or more external jumper conductors being connected between the jumper buses in one bundle of subconductors and the jumper buses in the other bundle.

Electro-optic component mounting device

DOEpatents

Gruchalla, Michael E.

1994-01-01

A technique is provided for integrally mounting a device such as an electro-optic device (50) in a transmission line to avoid series resonant effects. A center conductor (52) of the transmission line has an aperture (58) formed therein for receiving the device (50). The aperture (58) splits the center conductor into two parallel sections on opposite sides of the device. For a waveguide application, the center conductor is surrounded by a conductive ground surface (54), which is spaced apart from the center conductor with a dielectric material (56). One set of electrodes formed on the surface of the electro-optic device (50) is directly connected to the center conductor 52 and an electrode formed on the surface of the electro-optic device is directly connected to the conductive ground surface (54). The electrodes formed on the surface of the electro-optic device are formed on curved sections of the surface of the device to mate with correspondingly shaped electrodes on the conductor and ground surface to provide a uniform electric field across the electro-optic device. The center conductor includes a passage ( 60) formed therein for passage of optical signals to an electro-optic device.

Current-Induced Transistor Sensorics with Electrogenic Cells

PubMed Central

Fromherz, Peter

2016-01-01

The concepts of transistor recording of electroactive cells are considered, when the response is determined by a current-induced voltage in the electrolyte due to cellular activity. The relationship to traditional transistor recording, with an interface-induced response due to interactions with the open gate oxide, is addressed. For the geometry of a cell-substrate junction, the theory of a planar core-coat conductor is described with a one-compartment approximation. The fast electrical relaxation of the junction and the slow change of ion concentrations are pointed out. On that basis, various recording situations are considered and documented by experiments. For voltage-gated ion channels under voltage clamp, the effects of a changing extracellular ion concentration and the enhancement/depletion of ion conductances in the adherent membrane are addressed. Inhomogeneous ion conductances are crucial for transistor recording of neuronal action potentials. For a propagating action potential, the effects of an axon-substrate junction and the surrounding volume conductor are distinguished. Finally, a receptor-transistor-sensor is described, where the inhomogeneity of a ligand–activated ion conductance is achieved by diffusion of the agonist and inactivation of the conductance. Problems with regard to a development of reliable biosensors are mentioned. PMID:27120627

Lithospheric scale conductivity anomalies at the Proterozoic-Phanerozoic transition of Australia- Insights from AusLAMP MT data

NASA Astrophysics Data System (ADS)

Robertson, K. E.; Thiel, S.; Heinson, G. S.

2017-12-01

The intraplate deformation of the north-south trending Neoproterozoic Ikara-Flinders Ranges in South Australia, Australia, draws interest due to its high heat flow, elevated seismicity and the presence of diamondiferous kimberlites and mineral deposits. To the west lies the highly prospective Archean-Paleoproterozoic Gawler Craton, boasting the world's largest IOCG-U deposit, Olympic Dam. The Paleo-Mesoproterozoic Curnamona Province lies to the east, thought to have once been connected to the Gawler Craton and host to the world-class Broken Hill Ag-Pb-Zn deposit. A total of 162 long-period (10 s - 10,000 s) magnetotelluric (MT) stations from the Australia-wide AusLAMP (Australian Lithospheric Architecture Magnetotelluric Project) dataset were used to image the electrical resistivity beneath the Ikara-Flinders Ranges and adjacent Curnamona Province. The most recent acquisition extends this survey region northward to an area predominantly covered with Paleo-Mesozoic sedimentary basins including the most significant on-shore oil and gas region in Australia, the Cooper Basin. The resultant model from 3D inversions using ModEM software shows a relatively resistive Ikara-Flinders Ranges, with two parallel arcuate conductors (the WNAC and ENAC) at 20 to 80 km depth in the Nackara Arc. These conductors correlate well with locations of diamondiferous kimberlites which suggests that the conductors may have derived from the ascent of carbon-rich kimberlite-hosting magma and volatiles up large lithospheric scale structures. The conductors appear to have no correlation with regions of intraplate seismicity within the Ikara-Flinders Ranges which may mean that enhanced pore fluid pressure is not the main cause for the seismicity as was recently proposed. A large conductor covering most of the Curnamona Province (the CC) extends over depths of 10-40 km. The Curnamona Province's most recent tectonothermal activity is from Delamerian reworking during the Cambrian at its margins but is thought to exhibit a mostly cratonic core, supported by high wavespeeds imaged using seismic tomography. Given the pervasive nature of the conductor, it is attributed to a widespread fossil fluid flux event, perhaps either a long-lived response from Olarian (1.6 Ga) subduction-related fluids or a more recent event.

Development of aluminum-stabilized superconducting cables for the Mu2e detector solenoid

DOE PAGES

Lombardo, Vito; Buehler, M.; Lamm, M.; ...

2016-06-01

Here, the Mu2e experiment at Fermilab is designed to measure the rare process of direct muon-to-electron conversion in the field of a nucleus. The experiment comprises a system of three superconducting solenoids, which focus secondary muons from the production target and transport them to an aluminum stopping target, while minimizing the associated background. The Detector Solenoid (DS) is the last magnet in the transport line and its main functions are to provide a graded field in the region of the stopping target as well as a precision magnetic field in a volume large enough to house the tracker downstream ofmore » the stopping target. The Detector Solenoid coils are designed to be wound using NbTi Rutherford cables conformed in high purity aluminum for stabilization and then cold-worked for strength. Two types of Al-stabilized conductor are required to build the DS coils, one for the gradient section and one for the spectrometer section of the solenoid. The dimensions are optimized to generate the required field profile when the same current is transported in both conductors. The conductors contain NbTi Rutherford cables with 12 (DS1) and 8 (DS2) strands respectively and are manufactured by two different vendors. This paper describes the results of the manufacturing of production lengths of the Al-stabilized cables needed to build the Mu2e Detector Solenoid as well as the testing campaigns and main results. The main cable properties and results of electrical and mechanical tests are summarized and discussed for each stage of the cable development process. Results are compared to design values to show how the production cables satisfy all the design criteria starting from the NbTi wires to the Al-stabilized cables.« less

46 CFR 129.370 - Equipment grounding.

Code of Federal Regulations, 2011 CFR

2011-10-01

... and to a common ground by a conductor not normally carrying current. (b) Each metallic case of... grounding conductor must be sized to comply with section 250-95 of NEC (NFPA 70). (d) Each nonmetallic mast and topmast must have a lightning-ground conductor. ...

46 CFR 129.370 - Equipment grounding.

Code of Federal Regulations, 2010 CFR

2010-10-01

... and to a common ground by a conductor not normally carrying current. (b) Each metallic case of... grounding conductor must be sized to comply with section 250-95 of NEC (NFPA 70). (d) Each nonmetallic mast and topmast must have a lightning-ground conductor. ...

A device for testing cables

NASA Technical Reports Server (NTRS)

Hayhurst, Arthur Ray (Inventor)

1993-01-01

A device for testing current paths is attachable to a conductor. The device automatically checks the current paths of the conductor for continuity of a center conductor, continuity of a shield, and a short circuit between the shield and the center conductor. The device includes a pair of connectors and a circuit to provide for testing of the conductive paths of a cable to be tested with the circuit paths of the circuit. The circuit paths in the circuit include indicators to simultaneously indicate the results of the testing.

Radial electron-beam-breakup transit-time oscillator

DOEpatents

Kwan, Thomas J. T.; Mostrom, Michael A.

1998-01-01

A radial electron-beam-breakup transit-time oscillator (RBTO) provides a compact high power microwave generator. The RBTO includes a coaxial vacuum transmission line having an outer conductor and an inner conductor. The inner conductor defines an annular cavity with dimensions effective to support an electromagnetic field in a TEM.sub.00m mode. A radial field emission cathode is formed on the outer conductor for providing an electron beam directed toward the annular cavity electrode. Microwave energy is then extracted from the annular cavity electrode.

Solid cartridge for a pulse weld forming electrode and method of joining tubular members

DOEpatents

Bonnen, John Joseph Francis; Golovashchenko, Sergey Fedorovich; Mamutov, Alexander; Maison, Lloyd Douglas; Dawson, Scott Alwyn; deVries, James

2016-02-23

A cartridge assembly is disclosed for a pulse welding a first tube supported on a mandrel to a second tube. An outer tool is assembled over the second tube and a stored charge is discharged in the cartridge assembly. The cartridge comprises an annular conductor and a solid casing enveloping the conductor. The stored charge is electrically connected to the conductor and discharged through the conductor to compress the second tube and pulse weld the second tube to the first tube.

Electrically conductive connection for an electrode

DOEpatents

Hornack, Thomas R.; Chilko, Robert J.

1986-01-01

An electrically conductive connection for an electrode assembly of an electrolyte cell in which aluminum is produced by electrolysis in a molten salt is described. The electrode assembly comprises an electrode flask and a conductor rod. The flask has a collar above an area of minimum flask diameter. The electrically conductive connection comprises the electrode flask, the conductor rod and a structure bearing against the collar and the conductor rod for pulling the conductor rod into compressive and electrical contact with the flask.

Electrically conductive connection for an electrode

DOEpatents

Hornack, T.R.; Chilko, R.J.

1986-09-02

An electrically conductive connection for an electrode assembly of an electrolyte cell in which aluminum is produced by electrolysis in a molten salt is described. The electrode assembly comprises an electrode flask and a conductor rod. The flask has a collar above an area of minimum flask diameter. The electrically conductive connection comprises the electrode flask, the conductor rod and a structure bearing against the collar and the conductor rod for pulling the conductor rod into compressive and electrical contact with the flask. 2 figs.

Transitioning NWChem to the Next Generation of Manycore Machines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bylaska, Eric J.; Apra, E; Kowalski, Karol

The NorthWest chemistry (NWChem) modeling software is a popular molecular chemistry simulation software that was designed from the start to work on massively parallel processing supercomputers [1-3]. It contains an umbrella of modules that today includes self-consistent eld (SCF), second order Møller-Plesset perturbation theory (MP2), coupled cluster (CC), multiconguration self-consistent eld (MCSCF), selected conguration interaction (CI), tensor contraction engine (TCE) many body methods, density functional theory (DFT), time-dependent density functional theory (TDDFT), real-time time-dependent density functional theory, pseudopotential plane-wave density functional theory (PSPW), band structure (BAND), ab initio molecular dynamics (AIMD), Car-Parrinello molecular dynamics (MD), classical MD, hybrid quantum mechanicsmore » molecular mechanics (QM/MM), hybrid ab initio molecular dynamics molecular mechanics (AIMD/MM), gauge independent atomic orbital nuclear magnetic resonance (GIAO NMR), conductor like screening solvation model (COSMO), conductor-like screening solvation model based on density (COSMO-SMD), and reference interaction site model (RISM) solvation models, free energy simulations, reaction path optimization, parallel in time, among other capabilities [4]. Moreover, new capabilities continue to be added with each new release.« less

Electromagnetic properties of a modular MHD thruster

NASA Astrophysics Data System (ADS)

Kom, C. H.; Brunet, Y.

1999-04-01

The magnetic field of an annular MHD thruster made of independent superconducting modules has been studied with analytical and numerical methods. This configuration allows to obtain large magnetized volumes and high induction levels with rapidly decreasing stray fields. When some inductors are out of order, the thruster remains still operational, but the stray fields increase in the vicinity of the failure. For given structural materials and superconductors, it is possible to determine the size of the conductor in order to reduce the electromagnetic forces and the peak field supported by the conductors. For an active field of 10 T in a 6 m ray annular active channel of a thruster with 24 modules, the peak field is exactly 15.6 T in the Nb3Sn conductors and the structure has to sustain 10^8 N/m forces. The necessity to place some magnetic or superconducting shield is discussed, particularly when the thruster is in a degraded regime. Nous présentons une étude analytique et numérique du champ magnétique d'un propulseur MHD naval annulaire, constitué de secteurs inducteurs supraconducteurs. Cette configuration nécessite des champs magnétiques élevés dans des volumes importants, et permet une décroissance rapide des champs de fuite. Lorsque quelques inducteurs sont en panne, le propulseur reste toujours opérationnel, mais les champs de fuite sont importants aux environs des modules hors service. Étant donné un matériau supraconducteur, il est possible de déterminer la forme des inducteurs dans le but de réduire à la fois les forces électromagnétiques et le surchamp supporté par le bobinage. Pour un propulseur annulaire constitué de 24 modules inducteurs, et un champ actif de 10 T au centre de la partie active du canal (r = 6 m) on obtient avec du Nb3Sn un champ maximun sur le conducteur de 15,5 T et la structure supporte une force de 10^8 N/m. De plus, la nécessité de placer des écrans magnétique ou supraconducteur en régime dégradé (mise hors service d'un ou de plusieurs modules inducteurs) est discutée.

Stress-tuned conductor-polymer composite for use in sensors

DOEpatents

Martin, James E; Read, Douglas H

2013-10-22

A method for making a composite polymeric material with electrical conductivity determined by stress-tuning of the conductor-polymer composite, and sensors made with the stress-tuned conductor-polymer composite made by this method. Stress tuning is achieved by mixing a miscible liquid into the polymer precursor solution or by absorbing into the precursor solution a soluble compound from vapor in contact with the polymer precursor solution. The conductor may or may not be ordered by application of a magnetic field. The composite is formed by polymerization with the stress-tuning agent in the polymer matrix. The stress-tuning agent is removed following polymerization to produce a conductor-polymer composite with a stress field that depends on the amount of stress-tuning agent employed.

Carbon Nanotube-based Sensor and Method for Continually Sensing Changes in a Structure

NASA Technical Reports Server (NTRS)

Jordan, Jeffry D. (Inventor); Watkins, Anthony Neal (Inventor); Oglesby, Donald M. (Inventor); Ingram, JoAnne L. (Inventor)

2007-01-01

A sensor has a plurality of carbon nanotube (CNT)-based conductors operatively positioned on a substrate. The conductors are arranged side-by-side, such as in a substantially parallel relationship to one another. At least one pair of spaced-apart electrodes is coupled to opposing ends of the conductors. A portion of each of the conductors spanning between each pair of electrodes comprises a plurality of carbon nanotubes arranged end-to-end and substantially aligned along an axis. Because a direct correlation exists between resistance of a carbon nanotube and carbon nanotube strain, changes experienced by the portion of the structure to which the sensor is coupled induce a change in electrical properties of the conductors.

Compact orthogonal NMR field sensor

DOEpatents

Gerald, II, Rex E.; Rathke, Jerome W [Homer Glen, IL

2009-02-03

A Compact Orthogonal Field Sensor for emitting two orthogonal electro-magnetic fields in a common space. More particularly, a replacement inductor for existing NMR (Nuclear Magnetic Resonance) sensors to allow for NMR imaging. The Compact Orthogonal Field Sensor has a conductive coil and a central conductor electrically connected in series. The central conductor is at least partially surrounded by the coil. The coil and central conductor are electrically or electro-magnetically connected to a device having a means for producing or inducing a current through the coil and central conductor. The Compact Orthogonal Field Sensor can be used in NMR imaging applications to determine the position and the associated NMR spectrum of a sample within the electro-magnetic field of the central conductor.

30 CFR 75.601-3 - Short circuit protection; dual element fuses; current ratings; maximum values.

Code of Federal Regulations, 2011 CFR

2011-07-01

... devices shall not exceed the maximum values specified in this section: Conductor size (AWG or MGM) Single conductor cable Ampacity Max. fuse rating Two conductor cable Ampacity Max. fuse rating 14 15 15 12 20 20 10...

46 CFR 183.370 - General grounding requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... requirements. (a) A vessel's hull must not carry current as a conductor except for the following systems: (1... more, must have a grounding pole and a grounding conductor in the portable cord. (c) Each nonmetallic mast and top mast must have a lightning ground conductor. ...

46 CFR 183.370 - General grounding requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... requirements. (a) A vessel's hull must not carry current as a conductor except for the following systems: (1... more, must have a grounding pole and a grounding conductor in the portable cord. (c) Each nonmetallic mast and top mast must have a lightning ground conductor. ...

29 CFR 1910.304 - Wiring design and protection.

Code of Federal Regulations, 2012 CFR

2012-07-01

... grounding-type receptacles. (v) Receptacles connected to circuits having different voltages, frequencies, or... poles shall provide a horizontal climbing space not less than the following: (i) Power conductors below communication conductors—762 mm (30 in.); (ii) Power conductors alone or above communication conductors: (A) 300...

29 CFR 1910.304 - Wiring design and protection.

Code of Federal Regulations, 2010 CFR

2010-07-01

... grounding-type receptacles. (v) Receptacles connected to circuits having different voltages, frequencies, or... poles shall provide a horizontal climbing space not less than the following: (i) Power conductors below communication conductors—762 mm (30 in.); (ii) Power conductors alone or above communication conductors: (A) 300...

29 CFR 1910.304 - Wiring design and protection.

Code of Federal Regulations, 2013 CFR

2013-07-01

... grounding-type receptacles. (v) Receptacles connected to circuits having different voltages, frequencies, or... poles shall provide a horizontal climbing space not less than the following: (i) Power conductors below communication conductors—762 mm (30 in.); (ii) Power conductors alone or above communication conductors: (A) 300...

29 CFR 1910.304 - Wiring design and protection.

Code of Federal Regulations, 2011 CFR

2011-07-01

... grounding-type receptacles. (v) Receptacles connected to circuits having different voltages, frequencies, or... poles shall provide a horizontal climbing space not less than the following: (i) Power conductors below communication conductors—762 mm (30 in.); (ii) Power conductors alone or above communication conductors: (A) 300...

29 CFR 1910.304 - Wiring design and protection.

Code of Federal Regulations, 2014 CFR

2014-07-01

... grounding-type receptacles. (v) Receptacles connected to circuits having different voltages, frequencies, or... poles shall provide a horizontal climbing space not less than the following: (i) Power conductors below communication conductors—762 mm (30 in.); (ii) Power conductors alone or above communication conductors: (A) 300...

46 CFR 183.370 - General grounding requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... requirements. (a) A vessel's hull must not carry current as a conductor except for the following systems: (1... more, must have a grounding pole and a grounding conductor in the portable cord. (c) Each nonmetallic mast and top mast must have a lightning ground conductor. ...

High density associative memory

NASA Technical Reports Server (NTRS)

Moopenn, Alexander W. (Inventor); Thakoor, Anilkumar P. (Inventor); Daud, Taher (Inventor); Lambe, John J. (Inventor)

1989-01-01

A multi-layered, thin-film, digital memory having associative recall. There is a first memory matrix and a second memory matrix. Each memory matrix comprises, a first layer comprising a plurality of electrically separated row conductors; a second layer comprising a plurality of electrically separated column conductors intersecting but electrically separated from the row conductors; and, a plurality of resistance elements electrically connected between the row condutors and the column conductors at respective intersections of the row conductors and the column conductors, each resistance element comprising, in series, a first resistor of sufficiently high ohmage to conduct a sensible element current therethrough with virtually no heat-generating power consumption when a low voltage as employed in thin-film applications is applied thereacross and a second resistor of sufficiently high ohmage to conduct no sensible current therethrough when a low voltage as employed in thin-film applications is applied thereacross, the second resistor having the quality of breaking down to create a short therethrough upon the application of a breakdown level voltage across the first and second resistors.

Ultra-stretchable conductors based on buckled super-aligned carbon nanotube films.

PubMed

Yu, Yang; Luo, Shu; Sun, Li; Wu, Yang; Jiang, Kaili; Li, Qunqing; Wang, Jiaping; Fan, Shoushan

2015-06-14

Ultra-stretchable conductors are fabricated by coating super-aligned carbon nanotube (SACNT) films on pre-strained polydimethylsiloxane (PDMS) substrates and forming buckled SACNT structures on PDMS after release of the pre-strain. The parallel SACNT/PDMS conductors demonstrate excellent stability with normalized resistance changes of only 4.1% under an applied strain as high as 200%. The SACNT/PDMS conductors prepared with cross-stacked SACNT films show even lower resistance variation. The parallel SACNT/PDMS conductors exhibit high durability with a resistance increase of less than 5% after 10,000 cycles at 150% strain. In situ microscopic observations demonstrate that the buckled SACNT structures are straightened during the stretching process with reversible morphology evolution and thus the continuous SACNT conductive network can be protected from fracture. Due to the excellent electrical and mechanical properties of SACNT films and the formation of the buckled structure, SACNT/PDMS films exhibit high stretchability and durability, possessing great potential for use as ultra-stretchable conductors for wearable electronics, sensors, and energy storage devices.

Development of an YBCO coil with SSTC conductors for high field application

NASA Astrophysics Data System (ADS)

Shi, Y.; Liu, H. J.; Liu, F.; Tan, Y. F.; Jin, H.; Yu, M.; Lei, L.; Guo, L.; Hong, Z. Y.

2018-07-01

With the continuous reduction of the production costs and improvement of the transport performance, YBCO coated conductor is the most promising candidate for the high field magnet application due to its high irreversibility field and strong mechanical properties. Presently a stable production capacity of the YBCO conductors has been achieved by Shanghai Superconducting Technology Co., Ltd (SSTC) in China. Therefore, the demand in high field application with YBCO conductors is growing in China. This paper describes the design, fabrication and preliminary experiment of a solenoid coil with YBCO conductors supplied by SSTC to validate the possibility of high field application. Four same double pancakes were manufactured and assembled for the YBCO coil where the outer diameter and height was 54.3 and 48 mm respectively to match the dimensional limitation of the 14 T background magnets. The critical current (Ic) of YBCO conductors was obtained by measuring as a function of the applied field perpendicular to the YBCO conductor surface which provides the necessary input parameters for preliminary performance evaluation of the coil. Finally the preliminary test and discussion at 77 and 4.2 K were carried out. The consistency of four double pancakes Ic was achieved. The measured results indicate that the fabrication technology of HTS coil is reliable which gives the conference for the in-field test in high field application. This YBCO coil is the first demonstration of the SSTC YBCO coated conductors.

Gender recognition depends on type of movement and motor skill. Analyzing and perceiving biological motion in musical and nonmusical tasks.

PubMed

Wöllner, Clemens; Deconinck, Frederik J A

2013-05-01

Gender recognition in point-light displays was investigated with regard to body morphology cues and motion cues of human motion performed with different levels of technical skill. Gestures of male and female orchestral conductors were recorded with a motion capture system while they conducted excerpts from a Mendelssohn string symphony to musicians. Point-light displays of conductors were presented to observers under the following conditions: visual-only, auditory-only, audiovisual, and two non-conducting conditions (walking and static images). Observers distinguished between male and female conductors in gait and static images, but not in visual-only and auditory-only conducting conditions. Across all conductors, gender recognition for audiovisual stimuli was better than chance, yet significantly less reliable than for gait. Separate analyses for two groups of conductors indicated an expertise effect in that novice conductors' gender was perceived above chance level for visual-only and audiovisual conducting, while skilled conducting gestures of experts did not afford gender-specific cues. In these conditions, participants may have ignored the body morphology cues that led to correct judgments for static images. Results point to a response bias such that conductors were more often judged to be male. Thus judgment accuracy depended both on the conductors' level of expertise as well as on the observers' concepts, suggesting that perceivable differences between men and women may diminish for highly trained movements of experienced individuals. Copyright © 2013 Elsevier B.V. All rights reserved.

The Leaky Dielectric Model as a Weak Electrolyte Limit of an Electrodiffusion Model

NASA Astrophysics Data System (ADS)

Mori, Yoichiro; Young, Yuan-Nan

2017-11-01

The Taylor-Melcher (TM) model is the standard model for the electrohydrodynamics of poorly conducting leaky dielectric fluids under an electric field. The TM model treats the fluid as an ohmic conductor, without modeling ion dynamics. On the other hand, electrodiffusion models, which have been successful in describing electokinetic phenomena, incorporates ionic concentration dynamics. Mathematical reconciliation between electrodiffusion and the TM models has been a major issue for electrohydrodynamic theory. Here, we derive the TM model from an electrodiffusion model where we explicitly model the electrochemistry of ion dissociation. We introduce salt dissociation reaction in the bulk and take the limit of weak salt dissociation (corresponding to poor conductors in the TM model.) Assuming small Debye length we derive the TM model with or without the surface charge advection term depending upon the scaling of relevant dimensionless parameters. Our analysis also gives a description of the ionic concentration distribution within the Debye layer, which hints at possible scenarios for electrohydrodynamic singularity formation. In our analysis we also allow for a jump in voltage across the liquid interface which causes a drifting velocity for a liquid drop under an electric field. YM is partially supported by NSF-DMS-1516978 and NSF-DMS-1620316. YNY is partially supported by NSF-DMS-1412789 and NSF-DMS-1614863.

30 CFR 7.402 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... cable splice kit which becomes part of a splice. Conductor. A bare or insulated wire or combination of... assembly of one or more insulated conductors of electric current under a common or integral jacket. A cable may also contain one or more uninsulated conductors. Jacket. A nonmetallic abrasion-resistant outer...

30 CFR 7.402 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... cable splice kit which becomes part of a splice. Conductor. A bare or insulated wire or combination of... assembly of one or more insulated conductors of electric current under a common or integral jacket. A cable may also contain one or more uninsulated conductors. Jacket. A nonmetallic abrasion-resistant outer...

The Effect of Conductor Expressivity on Ensemble Performance Evaluation

ERIC Educational Resources Information Center

Morrison, Steven J.; Price, Harry E.; Geiger, Carla G.; Cornacchio, Rachel A.

2009-01-01

In this study, the authors examined whether a conductor's use of high-expressivity or low-expressivity techniques affected evaluations of ensemble performances that were identical across conducting conditions. Two conductors each conducted two 1-minute parallel excerpts from Percy Grainger's "Walking Tune." Each directed one excerpt…

Cognitive and Collaborative Demands of Freight Conductor Activities: Results and Implications of a Cognitive Task Analysis.

DOT National Transportation Integrated Search

2011-09-19

This paper reports the results of a cognitive task analysis (CTA) that examined the cognitive and collaborative demands placed on conductors and the knowledge and skills that experienced conductors have developed that enable them to operate safely an...

Cognitive and collaborative demands of freight conductor activities: results and implications of a cognitive task analysis

DOT National Transportation Integrated Search

2012-07-31

This report presents the results of a cognitive task analysis (CTA) that examined the cognitive and collaborative demands placed on conductors, as well as the knowledge and skills that experienced conductors have developed that enable them to operate...

30 CFR 57.12011 - High-potential electrical conductors.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential electrical...

30 CFR 57.12011 - High-potential electrical conductors.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential electrical...

30 CFR 57.12011 - High-potential electrical conductors.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential electrical...

Tribologic analyses of a self-mated aluminium contact used for overhead transmission lines

NASA Astrophysics Data System (ADS)

Steier, V. Franco

2017-05-01

The lifetime of aluminium components is often limited to their poor wear resistance. One example for such aluminium applications are overhead transmission lines. The sore points of these lines are the segments where the aluminium conductors are fixed to the line supports. The fixation is commonly realized via aluminium suspension clamps. Here, a superposition of different loads like traction and bending stresses, clamping forces and different types of wear occurs. To investigate the wear behaviour in these peculiar points, tribologic model tests were carried out. Within the tests, overhead conductor wires and aluminium plates, extracted from suspension clamps were reciprocally slid against aluminium plates (cylinder-on-plate test). The COF and a wear related parameter were recorded constantly. Subsequently, the loaded surfaces were analysed using confocal laser and electron scanning microscopy as well as energy dispersive X-ray spectroscopy. The investigation detected the formation of an oxidized tribologic layer between both components. The tribolayer, which mayor part adhered on the suspension clamps, was mostly formed from material removed from the conductor wires.

Mutual capacitance of liquid conductors in deformable tactile sensing arrays

NASA Astrophysics Data System (ADS)

Li, Bin; Fontecchio, Adam K.; Visell, Yon

2016-01-01

Advances in highly deformable electronics are needed in order to enable emerging categories of soft computing devices ranging from wearable electronics, to medical devices, and soft robotic components. The combination of highly elastic substrates with intrinsically stretchable conductors holds the promise of enabling electronic sensors that can conform to curved objects, reconfigurable displays, or soft biological tissues, including the skin. Here, we contribute sensing principles for tactile (mechanical image) sensors based on very low modulus polymer substrates with embedded liquid metal microfluidic arrays. The sensors are fabricated using a single-step casting method that utilizes fine nylon filaments to produce arrays of cylindrical channels on two layers. The liquid metal (gallium indium alloy) conductors that fill these channels readily adopt the shape of the embedding membrane, yielding levels of deformability greater than 400%, due to the use of soft polymer substrates. We modeled the sensor performance using electrostatic theory and continuum mechanics, yielding excellent agreement with experiments. Using a matrix-addressed capacitance measurement technique, we are able to resolve strain distributions with millimeter resolution over areas of several square centimeters.

Mutual capacitance of liquid conductors in deformable tactile sensing arrays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Bin; Fontecchio, Adam K.; Visell, Yon

2016-01-04

Advances in highly deformable electronics are needed in order to enable emerging categories of soft computing devices ranging from wearable electronics, to medical devices, and soft robotic components. The combination of highly elastic substrates with intrinsically stretchable conductors holds the promise of enabling electronic sensors that can conform to curved objects, reconfigurable displays, or soft biological tissues, including the skin. Here, we contribute sensing principles for tactile (mechanical image) sensors based on very low modulus polymer substrates with embedded liquid metal microfluidic arrays. The sensors are fabricated using a single-step casting method that utilizes fine nylon filaments to produce arraysmore » of cylindrical channels on two layers. The liquid metal (gallium indium alloy) conductors that fill these channels readily adopt the shape of the embedding membrane, yielding levels of deformability greater than 400%, due to the use of soft polymer substrates. We modeled the sensor performance using electrostatic theory and continuum mechanics, yielding excellent agreement with experiments. Using a matrix-addressed capacitance measurement technique, we are able to resolve strain distributions with millimeter resolution over areas of several square centimeters.« less

Combining EEG and MEG for the Reconstruction of Epileptic Activity Using a Calibrated Realistic Volume Conductor Model

PubMed Central

Aydin, Ümit; Vorwerk, Johannes; Küpper, Philipp; Heers, Marcel; Kugel, Harald; Galka, Andreas; Hamid, Laith; Wellmer, Jörg; Kellinghaus, Christoph; Rampp, Stefan; Wolters, Carsten Hermann

2014-01-01

To increase the reliability for the non-invasive determination of the irritative zone in presurgical epilepsy diagnosis, we introduce here a new experimental and methodological source analysis pipeline that combines the complementary information in EEG and MEG, and apply it to data from a patient, suffering from refractory focal epilepsy. Skull conductivity parameters in a six compartment finite element head model with brain anisotropy, constructed from individual MRI data, are estimated in a calibration procedure using somatosensory evoked potential (SEP) and field (SEF) data. These data are measured in a single run before acquisition of further runs of spontaneous epileptic activity. Our results show that even for single interictal spikes, volume conduction effects dominate over noise and need to be taken into account for accurate source analysis. While cerebrospinal fluid and brain anisotropy influence both modalities, only EEG is sensitive to skull conductivity and conductivity calibration significantly reduces the difference in especially depth localization of both modalities, emphasizing its importance for combining EEG and MEG source analysis. On the other hand, localization differences which are due to the distinct sensitivity profiles of EEG and MEG persist. In case of a moderate error in skull conductivity, combined source analysis results can still profit from the different sensitivity profiles of EEG and MEG to accurately determine location, orientation and strength of the underlying sources. On the other side, significant errors in skull modeling are reflected in EEG reconstruction errors and could reduce the goodness of fit to combined datasets. For combined EEG and MEG source analysis, we therefore recommend calibrating skull conductivity using additionally acquired SEP/SEF data. PMID:24671208

A Two-Dimensional Linear Bicharacteristic Scheme for Electromagnetics

NASA Technical Reports Server (NTRS)

Beggs, John H.

2002-01-01

The upwind leapfrog or Linear Bicharacteristic Scheme (LBS) has previously been implemented and demonstrated on one-dimensional electromagnetic wave propagation problems. This memorandum extends the Linear Bicharacteristic Scheme for computational electromagnetics to model lossy dielectric and magnetic materials and perfect electrical conductors in two dimensions. This is accomplished by proper implementation of the LBS for homogeneous lossy dielectric and magnetic media and for perfect electrical conductors. Both the Transverse Electric and Transverse Magnetic polarizations are considered. Computational requirements and a Fourier analysis are also discussed. Heterogeneous media are modeled through implementation of surface boundary conditions and no special extrapolations or interpolations at dielectric material boundaries are required. Results are presented for two-dimensional model problems on uniform grids, and the Finite Difference Time Domain (FDTD) algorithm is chosen as a convenient reference algorithm for comparison. The results demonstrate that the two-dimensional explicit LBS is a dissipation-free, second-order accurate algorithm which uses a smaller stencil than the FDTD algorithm, yet it has less phase velocity error.

Mechanism of Superconductivity in Quasi-Two-Dimensional Organic Conductor β-(BDA-TTP) Salts

NASA Astrophysics Data System (ADS)

Nonoyama, Yoshito; Maekawa, Yukiko; Kobayashi, Akito; Suzumura, Yoshikazu; Ito, Hiroshi

2008-09-01

We investigate theoretically the superconductivity of two-dimensional organic conductors, β-(BDA-TTP)2SbF6 and β-(BDA-TTP)2AsF6, to understand the role of the spin and charge fluctuations. The transition temperature is estimated by applying random phase approximation to an extended Hubbard model wherein realistic transfer energies are estimated by extended Hückel calculation. We find a gapless superconducting state with a dxy-like symmetry, which is consistent with the experimental results obtained by specific heat and scanning tunneling microscope. In the present model with an effectively half-filled triangular lattice, spin fluctuation competes with charge fluctuation as a mechanism of pairing interaction since both fluctuations have the same characteristic momentum q=(π,0) for V being smaller than U. This is in contrast to a model with a quarter-filled square lattice, wherein both fluctuations contribute cooperatively to pairing interaction due to fluctuations having different characteristic momenta. The resultant difference in the superconductivity of these two materials is also discussed.

Physical mechanism and numerical simulation of the inception of the lightning upward leader

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li Qingmin; Lu Xinchang; Shi Wei

2012-12-15

The upward leader is a key physical process of the leader progression model of lightning shielding. The inception mechanism and criterion of the upward leader need further understanding and clarification. Based on leader discharge theory, this paper proposes the critical electric field intensity of the stable upward leader (CEFISUL) and characterizes it by the valve electric field intensity on the conductor surface, E{sub L}, which is the basis of a new inception criterion for the upward leader. Through numerical simulation under various physical conditions, we verified that E{sub L} is mainly related to the conductor radius, and data fitting yieldsmore » the mathematical expression of E{sub L}. We further establish a computational model for lightning shielding performance of the transmission lines based on the proposed CEFISUL criterion, which reproduces the shielding failure rate of typical UHV transmission lines. The model-based calculation results agree well with the statistical data from on-site operations, which show the effectiveness and validity of the CEFISUL criterion.« less

Contrast source inversion (CSI) method to cross-hole radio-imaging (RIM) data - Part 2: A complex synthetic example and a case study

NASA Astrophysics Data System (ADS)

Li, Yongxing; Smith, Richard S.

2018-03-01

We present two examples of using the contrast source inversion (CSI) method to invert synthetic radio-imaging (RIM) data and field data. The synthetic model has two isolated conductors (one perfect conductor and one moderate conductor) embedded in a layered background. After inversion, we can identify the two conductors on the inverted image. The shape of the perfect conductor is better resolved than the shape of the moderate conductor. The inverted conductivity values of the two conductors are approximately the same, which demonstrates that the conductivity values cannot be correctly interpreted from the CSI results. The boundaries and the tilts of the upper and the lower conductive layers on the background can also be inferred from the results, but the centre parts of conductive layers in the inversion results are more conductive than the parts close to the boreholes. We used the straight-ray tomographic imaging method and the CSI method to invert the RIM field data collected using the FARA system between two boreholes in a mining area in Sudbury, Canada. The RIM data include the amplitude and the phase data collected using three frequencies: 312.5 kHz, 625 kHz and 1250 kHz. The data close to the ground surface have high amplitude values and complicated phase fluctuations, which are inferred to be contaminated by the reflected or refracted electromagnetic (EM) fields from the ground surface, and are removed for all frequencies. Higher-frequency EM waves attenuate more quickly in the subsurface environment, and the locations where the measurements are dominated by noise are also removed. When the data are interpreted with the straight-ray method, the images differ substantially for different frequencies. In addition, there are some unexpected features in the images, which are difficult to interpret. Compared with the straight-ray imaging results, the inversion results with the CSI method are more consistent for different frequencies. On the basis of what we learnt from the synthetic study, we interpret that there is one resistive layer across the middle of the borehole plane and two more conductive areas above and below this layer. Though there are some limitations in the study, such as large transmitter steps and the precise amplitudes and dipole moments being unknown, we conclude that the CSI method provides more interpretable images compared with the straight-ray method.

33 CFR 183.460 - Overcurrent protection: Special applications.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Requirements § 183.460 Overcurrent protection: Special applications. (a) Each ungrounded output conductor from... conductor is in the main power feed circuit from the battery to an engine cranking motor. The circuit breaker or fuse must be within 72 inches of the battery measured along the conductor, unless, for boats...

33 CFR 183.460 - Overcurrent protection: Special applications.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Requirements § 183.460 Overcurrent protection: Special applications. (a) Each ungrounded output conductor from... conductor is in the main power feed circuit from the battery to an engine cranking motor. The circuit breaker or fuse must be within 72 inches of the battery measured along the conductor, unless, for boats...

78 FR 37657 - Petition for a Waiver of Compliance

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-21

... of Conductors, at two of its maintenance operations. BTNA's first operation serves the Southern... Docket Number FRA-2013-0014. The conductor certification regulations provide that every train or yard crew, as defined in 49 CFR 218.5, Definitions, are required to have a certified conductor as a member...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, Kenneth A.; Knudson, Richard T.; Smith, Frank R.

Generally annular full tape thickness conductors are formed in single or multiple tape layers, and then stacked to produce an annular solid conductive wall for enclosing an electromagnetic isolation cavity. The conductors may be formed using punch and fill operations, or by flowing conductor-containing material onto the tape edge surfaces that define the interior sidewalls of the cavity.

46 CFR 111.50-3 - Protection of conductors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Protection of conductors. 111.50-3 Section 111.50-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... of overcurrent protection for conductors is to open the electric circuit if the current reaches a...

46 CFR 111.50-3 - Protection of conductors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Protection of conductors. 111.50-3 Section 111.50-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... of overcurrent protection for conductors is to open the electric circuit if the current reaches a...

46 CFR 111.50-3 - Protection of conductors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Protection of conductors. 111.50-3 Section 111.50-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... of overcurrent protection for conductors is to open the electric circuit if the current reaches a...

30 CFR 75.703-3 - Approved methods of grounding offtrack mobile, portable and stationary direct-current machines.

Code of Federal Regulations, 2011 CFR

2011-07-01

... separate grounding conductor located within the trailing cable of mobile and portable equipment and... conductor located within the direct-current power cable feeding stationary equipment and connected between... ground conductor connected between stationary equipment and the direct-current grounding medium; or, (d...

30 CFR 75.703-3 - Approved methods of grounding offtrack mobile, portable and stationary direct-current machines.

Code of Federal Regulations, 2012 CFR

2012-07-01

... separate grounding conductor located within the trailing cable of mobile and portable equipment and... conductor located within the direct-current power cable feeding stationary equipment and connected between... ground conductor connected between stationary equipment and the direct-current grounding medium; or, (d...

30 CFR 75.703-3 - Approved methods of grounding offtrack mobile, portable and stationary direct-current machines.

Code of Federal Regulations, 2013 CFR

2013-07-01

... separate grounding conductor located within the trailing cable of mobile and portable equipment and... conductor located within the direct-current power cable feeding stationary equipment and connected between... ground conductor connected between stationary equipment and the direct-current grounding medium; or, (d...