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Permissible Mine Equipment Approved to January 1, 1953: With Appended List of Available Flame-Lamp Fuels and Manufacturers of Flame-Resistant Trailing Cables

Description: From Introduction: "The present publication includes an appendix listening seven satisfactory fuels available for use in permissible flame safety lamps and shows where the fuels are available. This publication also includes an appendix listening manufactures of flame-resistant trailing cables, with the corresponding symbol that must be used by these manufactures in marketing trailing cables that have passed the test for flame resistance contained in Schedule 2E."
Date: 1954
Creator: Brunot, H. B.
Partner: UNT Libraries Government Documents Department

Rubber-Sheathed Trailing Cables

Description: From Introduction: "This paper records activities of the United States Bureau of Mines covering several years and reflects its endeavor to be of service to the coal-mining industry in procuring safer trailing cables for use on permissible machines."
Date: 1932
Creator: Ilsley, L. C.; Hooker, A. B. & Coggeshall, E. J.
Partner: UNT Libraries Government Documents Department

Causes of cracking of ignition cable

Description: From Summary: "The experiments described here show that the cracking at sharp bends, observed in the insulation of internal combustion engine high tension ignition wires after service, is due to a chemical attack upon the rubber by the ozone produced by the electric discharge that takes place at the surface of the cable. This cracking does not occur if the insulating material is not under tension, or if the cable is surrounded by some medium other than air. But it does occur even if the insulation is not subjected to electric stress, provided that the atmosphere near the cable contains ozone. The extent of this cracking varies greatly with the insulating material used. The cracking can be materially reduced by using braided cable and by avoiding sharp bends."
Date: February 1921
Creator: Dempsey, J. B. & Silsbee, F. B.
Partner: UNT Libraries Government Documents Department

The Reduction of the Critical Currents in Nb3Sn Cables under Transverse Loads

Description: The degradation of the critical current of impregnated Rutherford type Nb{sub 3}Sn cables is investigated as a function of the applied transverse load and magnetic field. The cable is made of TWCA modified jelly-roll type strand material and has a keystone angle of 1.0 degree. The voltage-current characteristics are determined for the magnetic field ranging from 2 to 11 tesla and transverse pressure up to 250 MPa on the cable surface. It is found that the 48-strand cable, made of strands with 6 elements in the matrix, shows a larger critical current degradation than the 26-strand cable with 36 elements per strand. The global degradation of the 48-strand cable is 63% at 150 MPa, and 40% at 150 MPa for the 26-strand cable. Micro-analysis of the cross-section shows permanent damage to the sharp edge of the cable. The influence of the keystone angle on the critical-current degradation is currently under investigation.
Date: August 1, 1992
Creator: Van Oort, J.M.; Scanlan, R.M.; Weijers, H.W.; Wessel, S. & Ten Kate, H.H.J.
Partner: UNT Libraries Government Documents Department

Cable Measuring Engine Operation Procedures

Description: The Cable Measuring Engine (CME) is a tool which measures and records the cable dimensions in a nondestructive fashion. It is used in-line with the superconductor cable as it is being made. The CME is intended to be used as a standard method of measuring cable by the various manufacturers involved in the cable process.
Date: July 11, 1997
Creator: Authors, Various
Partner: UNT Libraries Government Documents Department

In-situ FPGA debug driven by on-board microcontroller

Description: Often we are faced with the situation that the behavior of a circuit changes in an unpredictable way when chassis cover is attached or the system is not easily accessible. For instance, in a deployed environment, such as space, hardware can malfunction in unpredictable ways. What can a designer do to ascertain the cause of the problem? Register interrogations only go so far, and sometimes the problem being debugged is register transactions themselves, or the problem lies in FPGA programming. This work provides a solution to this; namely, the ability to drive a JTAG chain via an on-board microcontroller and use a simple clone of the Xilinx Chipscope core without a Xilinx JTAG cable or any external interfaces required. We have demonstrated the functionality of the prototype system using a Xilinx Spartan 3E FPGA and a Microchip PIC18j2550 microcontroller. This paper will discuss the implementation details as well as present case studies describing how the tools have aided satellite hardware development.
Date: January 1, 2009
Creator: Baker, Zachary Kent
Partner: UNT Libraries Government Documents Department

TRANSMISSION-LINE MISSILE ANTENNAS

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

Semiconductor Bridge Cable Test

Description: The semiconductor bridge (SCB) is an electroexplosive device used to initiate detonators. A C cable is commonly used to connect the SCB to a firing set. A series of tests were performed to identify smaller, lighter cables for firing single and multiple SCBs. This report provides a description of these tests and their results. It was demonstrated that lower threshold voltages and faster firing times can be achieved by increasing the wire size, which reduces ohmic losses. The RF 100 appears to be a reasonable substitute for C cable when firing single SCBs. This would reduce the cable volume by 68% and the weight by 67% while increasing the threshold voltage by only 22%. In general, RG 58 outperforms twisted pair when firing multiple SCBs in parallel. The RG 58's superior performance is attributed to its larger conductor size.
Date: January 1, 2002
Creator: KING, TONY L.
Partner: UNT Libraries Government Documents Department

Impedances of Tevatron separators

Description: The impedances of the Tevatron separators are revisited and are found to be negligibly small in the few hundred MHz region, except for resonances at 22.5 MHz. The later are contributions from the power cables which may drive head-tail instabilities if the bunch is long enough.
Date: May 28, 2003
Creator: Ng, K. Y.
Partner: UNT Libraries Government Documents Department

STUDY OF THE RHIC BPM SMA CONNECTOR FAILURE PROBLEM

Description: About 730 BPMs are mounted on the RHIC CQS and Triplet super-conducting magnets. Semi-rigid coaxial cables are used to bring the electrical signal from the BPM feedthroughs to the outside flanges. at the ambient temperature. Every year around 10 cables will lose their signals during the operation. The connection usually failed at the warm end of the cable. The problems were either the solder joint failed or the center conductor retracted out of the SMA connector. Finite element analyses were performed to understand the failure mechanism of the solder joint. The results showed that (1) The SMA center conductor can separate from the mating connector due to the thermal retraction. (2) The maximum thermal stress at the warm end solder joint can exceed the material strength of the Pb37/Sn63 solder material and (3) The magnet ramping frequency (-10 Hz), during the machine startup, can possibly resonant the coaxial cable and damage the solder joints, especially when a fracture is initiated. Test results confirmed that by using the silver bearing solder material (a higher strength material) and by crimping the cable at the locations close to the SMA connector (to prevent the center conductor from retracting) can effectively resolve the connector failure problem.
Date: June 25, 2007
Creator: LIAW,C.; SIKORA, R. & SCHROEDER, R.
Partner: UNT Libraries Government Documents Department

Field Demonstration of a 24-kV Superconducting Cable at Detroit Edison

Description: Customer acceptance of high temperature superconducting (HTS) cable technology requires a substantial field demonstration illustrating both the system's technical capabilities and its suitability for installation and operation within the utility environment. In this project, the world's first underground installation of an HTS cable using existing ductwork, a 120 meter demonstration cable circuit was designed and installed between the 24 kV bus distribution bus and a 120 kV-24 kV transformer at Detroit Edison's Frisbie substation. The system incorporated cables, accessories, a refrigeration system, and control instrumentation. Although the system was never put in operation because of problems with leaks in the cryostat, the project significantly advanced the state-of-the-art in the design and implementation of Warm Dielectric cable systems in substation applications. Lessons learned in this project are already being incorporated in several ongoing demonstration projects.
Date: December 1, 2004
Creator: Kelley, Nathan & Corsaro, Pietro
Partner: UNT Libraries Government Documents Department

Critical Current of Superconducting Rutherford Cable in High Magnetic Fields with Transverse Pressure

Description: For high energy physics applications superconducting cables are subjected to large stresses and high magnetic fields during service. It is essential to know how these cables perform in these operating conditions. A loading fixture capable of applying loads of up to 700 kN has been developed by NHMFL for LBNL. This fixture permits uniform loading of straight cables over a 122 mm length in a split-pair solenoid in fields up to 12 T at 4.2 K. The first results from this system for Rutherford cables of internal-tin and modified jelly roll strand of Nb{sub 3}Sn produced by IGC and TWC showed that little permanent degradation occurs up to 210 MPa. However, the cable made from internal-tin strand showed a 40% reduction in K{sub c} at 11T and 210 MPa while a dable made from modified jelly roll material showed only a 15% reduction in I{sub c} at 11T and 185 MPa.
Date: September 1, 1998
Creator: Dietderich, D.R.; Scanlan, R.M.; Walsh, R.P. & Miller, J.R.
Partner: UNT Libraries Government Documents Department

Report on Furukawa Coax #1

Description: This report contains the results of measurements performed on sample coax No.1 from the Furukawa Cable Co. of Japan. Time domain reflectometer (TOR) and RLC measurements were made at room temperature and superconducting. Network analyzer measurements of S11 and S21 were made for the superconducting coax.
Date: November 26, 1984
Creator: Peterson, D.
Partner: UNT Libraries Government Documents Department

Report on Furukawa Coax #2

Description: This report contains the results of measurements performed on sample coax No.2 from the Furukawa Cable Co. of Japan. Time domain reflectometer (TOR) and RLC measurements were made at room temperature and superconducting. Network analyzer measurements of S11 and S21 were made for the superconducting coax.
Date: December 6, 1984
Creator: Peterson, D.
Partner: UNT Libraries Government Documents Department

Analysis of a HTSC current lead under nonlinear heat transfer conditions

Description: The main objective of this paper is to consider the influence of the temperature dependence of the convective heat transfer coefficient on the optimal thermal design of the high temperature superconducting a HTSCI part of a cryogenic current lead. In the previous study the analysis of a HTSC lead was performed with the assumption that the heat transfer coefficient between the coolant (boil-off liquid helium) and the lead is finite but constant along the lead. In a present effort the heat transfer coefficient is allowed to vary along die lead causing an additional nonlinearity in the model. Numerically obtained current lead temperature profiles and corresponding helium vapor temperature profiles were used to calculate entropy generation within the lead as a function of the relevant design parameters. It has been demonstrated that additional nonlinearities do not cause a significant change of optimal design parameters.
Date: April 1, 1995
Creator: Sekulic, D.P.; Uzelac, Z. & Edeskuty, F.J.
Partner: UNT Libraries Government Documents Department

Superconducting current transformer for testing Nb3Sn cable splicing technique

Description: To provide a quick feedback on different approaches to superconducting cable splicing design and assembly techniques, a superconducting current transformer that can deliver more than 20 kA for testing splice samples has been designed and fabricated. The existing infrastructure of the Short Sample Test Facility at Fermilab, including its cryostat, power supply, and data acquisition system, was used for housing and operating the transformer. This report presents the design features of the transformer and the main results of cable splice tests.
Date: September 10, 2002
Creator: al., Nicolai Andreev et
Partner: UNT Libraries Government Documents Department