Measurement of the geometric parameters of power contact wire based on binocular stereovision

NASA Astrophysics Data System (ADS)

Pan, Xue-Tao; Zhang, Ya-feng; Meng, Fei

2010-10-01

In the electrified railway power supply system, electric locomotive obtains power from the catenary's wire through the pantograph. Under the action of the pantograph, combined with various factors such as vibration, touch current, relative sliding speed, load, etc, the contact wire will produce mechanical wear and electrical wear. Thus, in electrified railway construction and daily operations, the geometric parameters such as line height, pull value, the width of wear surface must be under real-timely and non-contact detection. On the one hand, the safe operation of electric railways will be guaranteed; on the other hand, the wire endurance will be extended, and operating costs reduced. Based on the characteristics of the worn wires' image signal, the binocular stereo vision technology was applied for measurement of contact wire geometry parameters, a mathematical model of measurement of geometric parameters was derived, and the boundaries of the wound wire abrasion-point value were extracted by means of sub-pixel edge detection method based on the LOG operator with the least-squares fitting, thus measurements of the wire geometry parameters were realized. Principles were demonstrated through simulation experiments, and the experimental results show that the detection methods presented in this paper for measuring the accuracy, efficiency and convenience, etc. are close to or superior to the traditional measurements, which has laid a good foundation for the measurement system of geometric parameters for the contact wire of the development of binocular vision.

Structural Analysis of Lightning Protection System for New Launch Vehicle

NASA Technical Reports Server (NTRS)

Cope, Anne; Moore, Steve; Pruss, Richard

2008-01-01

This project includes the design and specification of a lightning protection system for Launch Complex 39 B (LC39B) at Kennedy Space Center, FL in support of the Constellation Program. The purpose of the lightning protection system is to protect the Crew Launch Vehicle (CLV) or Cargo Launch Vehicle (CaLV) and associated launch equipment from direct lightning strikes during launch processing and other activities prior to flight. The design includes a three-tower, overhead catenary wire system to protect the vehicle and equipment on LC39B as described in the study that preceded this design effort: KSC-DX-8234 "Study: Construct Lightning Protection System LC3 9B". The study was a collaborative effort between Reynolds, Smith, and Hills (RS&H) and ASRC Aerospace (ASRC), where ASRC was responsible for the theoretical design and risk analysis of the lightning protection system and RS&H was responsible for the development of the civil and structural components; the mechanical systems; the electrical and grounding systems; and the siting of the lightning protection system. The study determined that a triangular network of overhead catenary cables and down conductors supported by three triangular free-standing towers approximately 594 ft tall (each equipped with a man lift, ladder, electrical systems, and communications systems) would provide a level of lightning protection for the Constellation Program CLV and CaLV on Launch Pad 39B that exceeds the design requirements.

Lightning Effects in the Payload Changeout Room

NASA Technical Reports Server (NTRS)

Thomas, Garland L.; Fisher, Franklin A.; Collier, Richard S.; Medelius, Pedro J.

1997-01-01

Analytical and empirical studies have been performed to provide better understanding of the electromagnetic environment inside the Payload Changeout Room and Orbiter payload bay resulting from lightning strikes to the launch pad lightning protection system. The analytical studies consisted of physical and mathematical modeling of the pad structure and the Payload Changeout Room. Empirical testing was performed using a lightning simulator to simulate controlled (8 kA) lightning strikes to the catenary wire lightning protection system. In addition to the analyses and testing listed above, an analysis of the configuration with the vehicle present was conducted, in lieu of testing, by the Finite Difference, Time Domain method.

KSC-2009-1299

NASA Image and Video Library

2009-01-22

CAPE CANAVERAL, Fla. – Progress is being made on construction of the new lightning towers on Launch Pad 39B at NASA's Kennedy Space Center in Florida. New sections are being added with the help of a giant crane. Three new lightning towers on the pad will be 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Kim Shiflett

KSC-2009-1004

NASA Image and Video Library

2009-01-02

CAPE CANAVERAL, Fla. – CAPE CANAVERAL, Fla. -- On Launch Pad 39B at NASA's Kennedy Space Center in Florida, another lightning tower is being constructed as part of the new lightning protection system for the Constellation Program and Ares/Orion launches. Each of the three new lightning towers will be 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Troy Cryder

KSC-2009-1005

NASA Image and Video Library

2009-01-02

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane (at left) completes construction of one of the towers in the new lightning protection system for the Constellation Program and Ares/Orion launches. At right, another tower is being constructed. Each of the three new lightning towers will be 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Troy Cryder

KSC-2009-1563

NASA Image and Video Library

2009-02-12

CAPE CANAVERAL, Fla. – A lightning mast remains to be lifted atop the third and final lightning tower erected on Launch Pad 39B at NASA's Kennedy Space Center. Three towers surround the pad. The new lightning protection system is being built for the Constellation Program and Ares/Orion launches. Each of the towers is 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Jack Pfaller

Cable-catenary large antenna concept

NASA Technical Reports Server (NTRS)

Akle, W.

1985-01-01

Deployable to very large diameters (over 1000 ft), while still remaining compatible with a complete satellite system launch by STS, the cable-catenary antenna comprises: 8 radial deployable boom masts; a deployable hub and feed support center mast; balanced front and back, radial and circumferential catenary cabling for highly accurate (mm) surface control; no interfering cabling in the antenna field; and an RF reflecting mesh supported on the front catenaries. Illustrations show the antenna-satellite system deployed and stowed configurations; the antenna deployment sequence; the design analysis logic; the sizing analysis output, and typical parametric design data.

The subsea deployment and installation of flexible pipe catenaries for the Enserch Garden Banks 388 Freestanding Production Riser

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

Herman, R.J.

1997-07-01

This narrative addresses the development of the subsea flexible pipe catenary handling tools and procedures as used in the Gulf of Mexico on the Enserch Garden Banks 388 Freestanding Production Riser. The philosophy that was invoked for the development of the tools and procedures was targeted on long term utilization and field maintenance capability with minimum vessel relocation requirements and minimum production interruptions. The initial emphasis for the required tools and procedures was to develop worker safe, environmentally friendly and cost effective equipment. These tools are for the deployment and installation of 3-inch Production and Annulus flexible pipe catenaries frommore » the Enserch Garden Banks 388 Floating Production Vessel to the system`s Freestanding Production Riser. The Pull In Jib system is common to the handling of all the catenaries. The Pull In Jib system has been designed to support the greater loads of the 8-inch and 12-inch export line catenaries.« less

KSC-2011-6165

NASA Image and Video Library

2011-08-03

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, the water tower and lightning protection system, consisting of three 600-foot-tall lightning towers, remain at Launch Pad 39B after the pad's deconstruction. Each lightning tower is 500 feet tall and topped off with an additional 100-foot fiberglass mast which supports a wire catenary system. In 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. For information on NASA's future plans, visit http://www.nasa.gov/exploration. Photo credit: NASA/Kim Shiflett

KSC-2009-1301

NASA Image and Video Library

2009-01-22

CAPE CANAVERAL, Fla. – Brilliant beams of sunlight bounce off the new lightning tower under construction on Launch Pad 39B at NASA's Kennedy Space Center in Florida. New sections are being added with the help of a giant crane (at right). Three new lightning towers on the pad will be 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Kim Shiflett

KSC-2010-4941

NASA Image and Video Library

2010-09-30

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, the rotating service structure (RSS) on Launch Pad 39B is being dismantled. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jim Grossmann

KSC-2010-4942

NASA Image and Video Library

2010-09-30

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, crews are dismantling the rotating service structure (RSS) on Launch Pad 39B. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jim Grossmann

KSC-2010-4946

NASA Image and Video Library

2010-09-30

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, crews are dismantling the rotating service structure (RSS) on Launch Pad 39B. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jim Grossmann

KSC-2010-4944

NASA Image and Video Library

2010-09-30

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, crews are dismantling the rotating service structure (RSS) on Launch Pad 39B. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jim Grossmann

KSC-2010-4943

NASA Image and Video Library

2010-09-30

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, the rotating service structure (RSS) on Launch Pad 39B is being dismantled. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jim Grossmann

KSC-2010-4945

NASA Image and Video Library

2010-09-30

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, the rotating service structure (RSS) on Launch Pad 39B is being dismantled. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jim Grossmann

KSC-2010-4987

NASA Image and Video Library

2010-10-04

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, crews continue dismantling the rotating service structure (RSS) on Launch Pad 39B. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jack Pfaller

KSC-2009-1942

NASA Image and Video Library

2009-03-03

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane has removed the 80-foot lightning mast from the top of the fixed service structure. The mast is no longer needed with the erection of the three lightning towers around the pad. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. The three new lightning towers are 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Amanda Diller

KSC-2009-1562

NASA Image and Video Library

2009-02-12

CAPE CANAVERAL, Fla. – The faint sunrise sky over NASA's Kennedy Space Center casts the newly erected lightning towers on Launch Pad 39B in silhouette. They surround the fixed and rotating service structures at center that have served the Space Shuttle Program. The new lightning protection system is being built for the Constellation Program and Ares/Orion launches. Each of the towers is 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Jack Pfaller

KSC-2009-1001

NASA Image and Video Library

2009-01-02

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane completes construction of one of the towers in the new lightning protection system for the Constellation Program and Ares/Orion launches. Other towers are being constructed at left and behind the service structures on the pad. Each of the three new lightning towers will be 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Troy Cryder

KSC-2009-1008

NASA Image and Video Library

2009-01-02

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane places the 100-foot fiberglass mast atop the new lightning tower constructed on the pad. The towers are part of the new lightning protection system for the Constellation Program and Ares/Orion launches. Each of the three new lightning towers will be 500 feet tall with the additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Kim Shiflett

KSC-2009-1006

NASA Image and Video Library

2009-01-02

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane places the 100-foot fiberglass mast atop the new lightning tower constructed on the pad. The towers are part of the new lightning protection system for the Constellation Program and Ares/Orion launches. Each of the three new lightning towers will be 500 feet tall with the additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Kim Shiflett

Review of pantograph and catenary interaction

NASA Astrophysics Data System (ADS)

Zhang, Weihua; Zou, Dong; Tan, Mengying; Zhou, Ning; Li, Ruiping; Mei, Guiming

2018-06-01

The application of electrified railway directly promotes relevant studies on pantograph-catenary interaction. With the increase of train running speed, the operating conditions for pantograph and catenary have become increasingly complex. This paper reviews the related achievements contributed by groups and institutions around the world. This article specifically focuses on three aspects: The dynamic characteristics of the pantograph and catenary components, the systems' dynamic properties, and the environmental influences on the pantograph-catenary interaction. In accordance with the existing studies, future research may prioritize the task of identifying the mechanism of contact force variation. This kind of study can be carried out by simplifying the pantograph-catenary interaction into a moving load problem and utilizing the theory of matching mechanical impedance. In addition, developing a computational platform that accommodates environmental interferences and multi-field coupling effects is necessary in order to further explore applications based on fundamental studies.

Microcomputer design and analysis of the cable catenary large space antenna system

NASA Technical Reports Server (NTRS)

Akle, W.

1984-01-01

The use of microcomputers in the design of a cable catenary large space antenna system is discussed. The development of a system design capability, data base utilization, systems integration, program structure and logic, and integrated graphics output are discussed.

KSC-2010-4984

NASA Image and Video Library

2010-10-04

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, this image shows the progress of the rotating service structure (RSS) on Launch Pad 39B as it is being dismantled. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jack Pfaller

KSC-2010-4988

NASA Image and Video Library

2010-10-04

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, this long range view shows the progress of the rotating service structure (RSS) on Launch Pad 39B as it is being dismantled. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jack Pfaller

KSC-2010-4986

NASA Image and Video Library

2010-10-04

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, this image shows the progress of the rotating service structure (RSS) on Launch Pad 39B as it is being dismantled. Sand, reinforcing steel and large wooden mats were put down under the RSS to protect the structure's concrete from falling debris during deconstruction. Starting in 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of vehicles. The new lightning protection system, consisting of three lightning towers and a wire catenary system will remain. Photo credit: NASA/Jack Pfaller

KSC-2009-1943

NASA Image and Video Library

2009-03-03

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane lowers the 80-foot lightning mast removed from the top of the fixed service structure (left) onto the pad surface. The mast is no longer needed with the erection of the three lightning towers around the pad. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. The three new lightning towers are 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Amanda Diller

KSC-2009-1945

NASA Image and Video Library

2009-03-03

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, the 80-foot lightning mast removed from the top of the fixed service structure (behind it) is lowered onto the pad surface. The mast is no longer needed with the erection of the three lightning towers around the pad. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. The three new lightning towers are 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Amanda Diller

KSC-2009-1947

NASA Image and Video Library

2009-03-03

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, the 80-foot lightning mast removed from the top of the fixed service structure (left) rests on the pad surface. The mast is no longer needed with the erection of the three lightning towers around the pad. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. The three new lightning towers are 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Amanda Diller

KSC-2009-1941

NASA Image and Video Library

2009-03-03

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane is being used to remove the 80-foot lightning mast from the top of the fixed service structure. The mast is no longer needed with the erection of the three lightning towers around the pad. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. The three new lightning towers are 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Amanda Diller

KSC-2009-1940

NASA Image and Video Library

2009-03-03

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane is being used to remove the 80-foot lightning mast from the top of the fixed service structure. The mast is no longer needed with the erection of the three lightning towers around the pad. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. The three new lightning towers are 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Amanda Diller

KSC-2009-1946

NASA Image and Video Library

2009-03-03

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, the 80-foot lightning mast removed from the top of the fixed service structure (center) rests on the pad surface. The mast is no longer needed with the erection of the three lightning towers around the pad. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. The three new lightning towers are 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Amanda Diller

KSC-2009-1584

NASA Image and Video Library

2009-02-13

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, the 100-foot lightning mast has been raised to vertical. It will be lifted and installed on top of the third and final new lightning tower being erected around the pad. The new lightning protection system is being built for the Constellation Program and Ares/Orion launches. Each of the towers is 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Tim Jacobs

KSC-2009-1002

NASA Image and Video Library

2009-01-02

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, equipment surrounds the service structures for the construction of towers in the new lightning protection system for the Constellation Program and Ares/Orion launches. In the foreground is part of the giant crane used to place segments on the towers. Each of the three new lightning towers will be 500 feet tall with an additional 100-foot fiberglass mast (seen on the ground) atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Troy Cryder

KSC-2009-1007

NASA Image and Video Library

2009-01-02

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, a crane places the 100-foot fiberglass mast atop the new lightning tower constructed on the pad. The towers are part of the new lightning protection system for the Constellation Program and Ares/Orion launches. At left of the service structures is another tower under construction. Each of the three new lightning towers will be 500 feet tall with the additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Kim Shiflett

7. OBLIQUE VIEW, HOME SIGNAL, WESTBOUND ON CATENARY BRIDGE 518 ...

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

7. OBLIQUE VIEW, HOME SIGNAL, WESTBOUND ON CATENARY BRIDGE 518 - New York, New Haven & Hartford Railroad, Automatic Signalization System, Long Island Sound shoreline between Stamford & New Haven, Stamford, Fairfield County, CT

KSC-2009-1944

NASA Image and Video Library

2009-03-03

CAPE CANAVERAL, Fla. – On Launch Pad 39B at NASA's Kennedy Space Center in Florida, workers attach more cables to the 80-foot lightning mast removed from the top of the fixed service structure. The mast will be lowered to horizontal for transport from the pad. The mast is no longer needed with the erection of the three lightning towers around the pad. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. The three new lightning towers are 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Photo credit: NASA/Amanda Diller

KSC-2009-1561

NASA Image and Video Library

2009-02-12

CAPE CANAVERAL, Fla. – The faint sunrise sky over NASA's Kennedy Space Center casts the newly erected lightning towers on Launch Pad 39B in silhouette. The two towers at left contain the lightning mast on top; the one at right does not. At center are the fixed and rotating service structures that have served the Space Shuttle Program. The new lightning protection system is being built for the Constellation Program and Ares/Orion launches. Each of the towers is 500 feet tall with an additional 100-foot fiberglass mast atop supporting a wire catenary system. This improved lightning protection system allows for the taller height of the Ares I rocket compared to the space shuttle. Pad 39B will be the site of the first Ares vehicle launch, including the Ares I-X test flight that is targeted for July 2009. Photo credit: NASA/Jack Pfaller

Fuzzy Energy Management for a Catenary-Battery-Ultracapacitor based Hybrid Tramway

NASA Astrophysics Data System (ADS)

Jibin, Yang; Jiye, Zhang; Pengyun, Song

2017-05-01

In this paper, an energy management strategy (EMS) based on fuzzy logic control for a catenary-battery-ultracapacitor powered hybrid modern tramway was presented. The fuzzy logic controller for the catenary zone and catenary-less zone was respectively designed by analyzing the structure and working mode of the hybrid system, then an energy management strategy based on double fuzzy logic control was proposed to enhance the fuel economy. The hybrid modern tramway simulation model was developed based on MATLAB/Simulink environment. The simulation results show that the proposed EMS can satisfy the demand of dynamic performance of the tramway and achieve the power distribution reasonably between the each power source.

KSC-2009-3126

NASA Image and Video Library

2009-05-11

CAPE CANAVERAL, Fla. – This photo shows one of two lightning strikes that occurred on May 11 around 11 p.m. within a third of a mile of space shuttle Endeavour on Launch Pad 39B at NASA's Kennedy Space Center in Florida. Engineers and safety personnel evaluated data and performed a walkdown of the pad and determined there is no damage to the vehicle or the pad. The images are from Kennedy's Operational Television cameras which can be used to triangulate the location of lightning strikes. Other detection systems include the Cloud-To-Ground Lightning Surveillance System, Strikenet/National Lightning Detection Network, Lightning Induced Voltage Instrumentation System and the Catenary Wire Lightning Instrumentation System. Endeavour is standing by on the pad, prepared for liftoff in the unlikely event that a rescue mission is necessary during space shuttle Atlantis' STS-125 mission to service NASA's Hubble Space Telescope. Photo credit: NASA

KSC-2009-3125

NASA Image and Video Library

2009-05-11

CAPE CANAVERAL, Fla. – This photo shows one of two lightning strikes that occurred on May 11 around 11 p.m. within a third of a mile of space shuttle Endeavour on Launch Pad 39B at NASA's Kennedy Space Center in Florida. Engineers and safety personnel evaluated data and performed a walkdown of the pad and determined there is no damage to the vehicle or the pad. The images are from Kennedy's Operational Television cameras which can be used to triangulate the location of lightning strikes. Other detection systems include the Cloud-To-Ground Lightning Surveillance System, Strikenet/National Lightning Detection Network, Lightning Induced Voltage Instrumentation System and the Catenary Wire Lightning Instrumentation System. Endeavour is standing by on the pad, prepared for liftoff in the unlikely event that a rescue mission is necessary during space shuttle Atlantis' STS-125 mission to service NASA's Hubble Space Telescope. Photo credit: NASA

KSC-2009-3127

NASA Image and Video Library

2009-05-11

CAPE CANAVERAL, Fla. – This photo taken from Launch Pad 39A at NASA's Kennedy Space Center in Florida shows one of two lightning strikes that occurred on May 11 around 11 p.m. within a third of a mile of space shuttle Endeavour on Launch Pad 39B. Engineers and safety personnel evaluated data and performed a walkdown of the pad and determined there is no damage to the vehicle or the pad. The images are from Kennedy's Operational Television cameras which can be used to triangulate the location of lightning strikes. Other detection systems include the Cloud-To-Ground Lightning Surveillance System, Strikenet/National Lightning Detection Network, Lightning Induced Voltage Instrumentation System and the Catenary Wire Lightning Instrumentation System. Endeavour is standing by on the pad, prepared for liftoff in the unlikely event that a rescue mission is necessary during space shuttle Atlantis' STS-125 mission to service NASA's Hubble Space Telescope. Photo credit: NASA

KSC-2011-6091

NASA Image and Video Library

2011-08-03

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, cleanup of Launch Pad 39B is in progress beside the pad's flame trench. The trench is 450 feet long, 58 feet wide and 42 feet deep with an inner inverted V-shaped steel flame deflector. Sand, reinforcing steel and large wooden mats were placed over the pad's concrete surfaces during deconstruction to protect them from falling debris. In the distance is the 525-foot-tall Vehicle Assembly Building. In 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of rockets and spacecraft. The lightning protection system, consisting of three lightning towers and a wire catenary system, will remain. For information on NASA's future plans, visit http://www.nasa.gov/exploration. Photo credit: NASA/Kim Shiflett

KSC-2011-6090

NASA Image and Video Library

2011-08-03

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, cleanup of Launch Pad 39B is in progress beside the pad's flame trench. The trench is 450 feet long, 58 feet wide and 42 feet deep with an inner inverted V-shaped steel flame deflector. Sand, reinforcing steel and large wooden mats were placed over the pad's concrete surfaces during deconstruction to protect them from falling debris. In 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of rockets and spacecraft. The lightning protection system, consisting of three lightning towers and a wire catenary system, will remain. For information on NASA's future plans, visit http://www.nasa.gov/exploration. Photo credit: NASA/Kim Shiflett

KSC-2011-6088

NASA Image and Video Library

2011-08-03

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, cleanup of Launch Pad 39B is in progress beside the pad's flame trench. The trench is 450 feet long, 58 feet wide and 42 feet deep with an inner inverted V-shaped steel flame deflector. Sand, reinforcing steel and large wooden mats were placed over the pad's concrete surfaces during deconstruction to protect them from falling debris. In the distance is the 525-foot-tall Vehicle Assembly Building. In 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of rockets and spacecraft. The lightning protection system, consisting of three lightning towers and a wire catenary system, will remain. For information on NASA's future plans, visit http://www.nasa.gov/exploration. Photo credit: NASA/Kim Shiflett

KSC-2011-6089

NASA Image and Video Library

2011-08-03

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, cleanup of Launch Pad 39B is in progress beside the pad's flame trench. The trench is 450 feet long, 58 feet wide and 42 feet deep with an inner inverted V-shaped steel flame deflector. Sand, reinforcing steel and large wooden mats were placed over the pad's concrete surfaces during deconstruction to protect them from falling debris. In the distance is the 525-foot-tall Vehicle Assembly Building. In 2009, the structure at the pad was no longer needed for NASA's Space Shuttle Program, so it is being restructured for future use. The new design will feature a "clean pad" for rockets to come with their own launcher, making it more versatile for a number of rockets and spacecraft. The lightning protection system, consisting of three lightning towers and a wire catenary system, will remain. For information on NASA's future plans, visit http://www.nasa.gov/exploration. Photo credit: NASA/Kim Shiflett

W3MAMCAT: a world wide web based tool for mammillary and catenary compartmental modeling and expert system distinguishability.

PubMed

Russell, Solomon; Distefano, Joseph J

2006-07-01

W(3)MAMCAT is a new web-based and interactive system for building and quantifying the parameters or parameter ranges of n-compartment mammillary and catenary model structures, with input and output in the first compartment, from unstructured multiexponential (sum-of-n-exponentials) models. It handles unidentifiable as well as identifiable models and, as such, provides finite parameter interval solutions for unidentifiable models, whereas direct parameter search programs typically do not. It also tutorially develops the theory of model distinguishability for same order mammillary versus catenary models, as did its desktop application predecessor MAMCAT+. This includes expert system analysis for distinguishing mammillary from catenary structures, given input and output in similarly numbered compartments. W(3)MAMCAT provides for universal deployment via the internet and enhanced application error checking. It uses supported Microsoft technologies to form an extensible application framework for maintaining a stable and easily updatable application. Most important, anybody, anywhere, is welcome to access it using Internet Explorer 6.0 over the internet for their teaching or research needs. It is available on the Biocybernetics Laboratory website at UCLA: www.biocyb.cs.ucla.edu.

The Locus of the Focus of a Rolling Parabola

ERIC Educational Resources Information Center

Agarwal, Anurag; Marengo, James

2010-01-01

The catenary is usually introduced as the shape assumed by a hanging flexible cable. This is a "physical" description of a catenary. In this article we give a "geometrical" description of a catenary. Specifically we show that the catenary is the locus of the focus of a certain parabola as it rolls on the x-axis.

In Praise of the Catenary

NASA Astrophysics Data System (ADS)

Behroozi, F.

2018-04-01

When a chain hangs loosely from its end points, it takes the familiar form known as the catenary. Power lines, clothes lines, and chain links are familiar examples of the catenary in everyday life. Nevertheless, the subject is conspicuously absent from current introductory physics and calculus courses. Even in upper-level physics and math courses, the catenary equation is usually introduced as an example of hyperbolic functions or discussed as an application of the calculus of variations. We present a new derivation of the catenary equation that is suitable for introductory physics and mathematics courses.

Visual method for detecting critical damage in railway contact strips

NASA Astrophysics Data System (ADS)

Judek, S.; Skibicki, J.

2018-05-01

Ensuring an uninterrupted supply of power in the electric traction is vital for the safety of this important transport system. For this purpose, monitoring and diagnostics of the technical condition of the vehicle’s power supply elements are becoming increasingly common. This paper presents a new visual method for detecting contact strip damage, based on measurement and analysis of the movement of the overhead contact line (OCL) wire. A measurement system configuration with a 2D camera was proposed. The experimental method has shown that contact strips damage can be detected by transverse displacement signal analysis. It has been proven that the velocity signal numerically established on that basis has a comparable level in the case of identical damage, regardless of its location on the surface of the contact strip. The proposed method belongs to the group of contact-less measurements, so it does not require interference with the structure of the catenary network nor the mounting of sensors in its vicinity. Measurement of displacements of the contact wire in 2D space makes it possible to combine the functions of existing diagnostic stands assessing the correctness of the mean contact force control adjustment of the current collector with the elements of the contact strip diagnostics, which involves detecting their damage which may result in overhead contact line rupture.

On the implementation of an auxiliary pantograph for speed increase on existing lines

NASA Astrophysics Data System (ADS)

Liu, Zhendong; Jönsson, Per-Anders; Stichel, Sebastian; Rønnquist, Anders

2016-08-01

The contact between pantograph and catenary at high speeds suffers from high dynamic contact force variation due to stiffness variations and wave propagation. To increase operational speed on an existing catenary system, especially for soft catenary systems, technical upgrading is usually necessary. Therefore, it is desirable to explore a more practical and cost-saving method to increase the operational speed. Based on a 3D pantograph-catenary finite element model, a parametric study on two-pantograph operation with short spacing distances at high speeds shows that, although the performance of the leading pantograph gets deteriorated, the trailing pantograph feels an improvement if pantographs are spaced at a proper distance. Then, two main positive effects, which can cause the improvement, are addressed. Based on a discussion on wear mechanisms, this paper suggests to use the leading pantograph as an auxiliary pantograph, which does not conduct any electric current, to minimise additional wear caused by the leading pantograph. To help implementation and achieve further improvement under this working condition, this paper investigates cases with optimised uplift force on the leading pantograph and with system parameter deviations. The results show that the two positive effects still remain even with some system parameter deviations. About 30% of speed increase should be possibly achieved still sustaining a good dynamic performance with help of the optimised uplift force.

Method and apparatus for production of subsea hydrocarbon formations

DOEpatents

Blandford, Joseph W.

1994-01-01

A well tender system for controlling, separating, storing and offloading well fluids produced from subsea hydrocarbon formations. The system comprises a vertically aligned series of tethered cylindrical tanks which are torsionally stabilized by flexible catenary production riser and export riser bundles, and serviced by separate catenary pipe bundles. Piles are secured to the seabed, each pile assembly being pivotally connected to a lower rigid tendon, which is in turn connected to tendons arranged about the periphery of the interconnected cylindrical tanks.

Method and apparatus for production of subsea hydrocarbon formations

DOEpatents

Blandford, Joseph W.

1992-01-01

A well tender system for controlling, separating, storing and offloading well fluids produced from subsea hydrocarbon formations. The system comprises a vertically aligned series of tethered cylindrical tanks which are torsionally stabilized by flexible catenary production riser and expert riser bundles, and serviced by separate catenary pipe bundles. Piles are secured to the seabed, each pile assembly being pivotally connected to a lower rigid tendon, which is in turn connected to tendons arranged about the periphery of the interconnected cylindrical tanks.

Long-range distributed optical fiber hot-wire anemometer based on chirped-pulse ΦOTDR.

PubMed

Garcia-Ruiz, Andres; Dominguez-Lopez, Alejandro; Pastor-Graells, Juan; Martins, Hugo F; Martin-Lopez, Sonia; Gonzalez-Herraez, Miguel

2018-01-08

We demonstrate a technique allowing to develop a fully distributed optical fiber hot-wire anemometer capable of reaching a wind speed uncertainty of ≈ ±0.15m/s (±0.54km/h) at only 60 mW/m of dissipated power in the sensing fiber, and within only four minutes of measurement time. This corresponds to similar uncertainty values than previous papers on distributed optical fiber anemometry but requires two orders of magnitude smaller dissipated power and covers at least one order of magnitude longer distance. This breakthrough is possible thanks to the extreme temperature sensitivity and single-shot performance of chirped-pulse phase-sensitive optical time domain reflectometry (ΦOTDR), together with the availability of metal-coated fibers. To achieve these results, a modulated current is fed through the metal coating of the fiber, causing a modulated temperature variation of the fiber core due to Joule effect. The amplitude of this temperature modulation is strongly dependent on the wind speed at which the fiber is subject. Continuous monitoring of the temperature modulation along the fiber allows to determine the wind speed with singular low power injection requirements. Moreover, this procedure makes the system immune to temperature drifts of the fiber, potentially allowing for a simple field deployment. Being a much less power-hungry scheme, this method also allows for monitoring over much longer distances, in the orders of 10s of km. We expect that this system can have application in dynamic line rating and lateral wind monitoring in railway catenary wires.

The Effect of a Soap Film on a Catenary: Measurement of Surface Tension from the Triangular Configuration

ERIC Educational Resources Information Center

Behroozi, F.; Behroozi, P. S.

2011-01-01

A chain assumes the well-known shape known as a catenary when it hangs loosely from two points in a gravitational field. The correct solution of the catenary was one of the early triumphs of the newly invented calculus of variations at the end of the 17th century. Here we revisit the catenary and show that, for a chain hanging from a horizontal…

Program for catenary-pantograph analysis, PrOSA statement of methods and validation according EN 50318

NASA Astrophysics Data System (ADS)

Finner, Lars; Poetsch, Gero; Sarnes, Bernhard; Kolbe, Michael

2015-03-01

DB Systemtechnik is a high-performing, customer-driven service provider that, as well as authoritatively serving the Deutsche Bahn Group by dint of its specialist knowledge is also increasingly active on the global railway market. Development and testing of pantograph models and catenary systems have been part of the company's essential activity fields from the beginning. Therefore, an efficient and high-performing simulation tool is indispensable. That is why DB Systemtechnik spent high efforts to develop the program PrOSA in cooperation with the Heinz-Nixdorf-Institut (HNI) of the university Paderborn to simulate the interaction of pantograph and catenary. This article gives an overview of the most relevant properties of PrOSA. Furthermore, it is described how the benchmark requirements were implemented and processed.

In Praise of the Catenary

ERIC Educational Resources Information Center

Behroozi, F.

2018-01-01

When a chain hangs loosely from its end points, it takes the familiar form known as the catenary. Power lines, clothes lines, and chain links are familiar examples of the catenary in everyday life. Nevertheless, the subject is conspicuously absent from current introductory physics and calculus courses. Even in upper-level physics and math courses,…

The Hyperbolic Sine Cardinal and the Catenary

ERIC Educational Resources Information Center

Sanchez-Reyes, Javier

2012-01-01

The hyperbolic function sinh(x)/x receives scant attention in the literature. We show that it admits a clear geometric interpretation as the ratio between length and chord of a symmetric catenary segment. The inverse, together with the use of dimensionless parameters, furnishes a compact, explicit construction of a general catenary segment of…

KSC-2009-3940

NASA Image and Video Library

2009-07-10

CAPE CANAVERAL, Fla. – A lightning strike on Launch Pad 39A at NASA's Kennedy Space Center in Florida is captured by an Operational Television camera. Eleven lightning strikes occurred within .35 miles of the pad during a thunderstorm July 10 as space shuttle Endeavour was prepared for launch. Mission managers decided to delay Endeavour's planned liftoff July 11 as a precaution to allow engineers and safety personnel time to analyze data and retest systems on the orbiter and solid rockets boosters. The next launch attempt for the STS-127 mission is planned for Sunday, July 12, at 7:13 p.m. EDT. The Operational Television cameras can be used to triangulate the location of lightning strikes. Other detection systems include the Cloud-To-Ground Lightning Surveillance System, Strikenet/National Lightning Detection Network, Lightning Induced Voltage Instrumentation System and the Catenary Wire Lightning Instrumentation System. Endeavour will deliver the Japanese Experiment Module's Exposed Facility, or JEM-EF, and the Experiment Logistics Module-Exposed Section, or ELM-ES, in the final of three flights dedicated to the assembly of the Japan Aerospace Exploration Agency's Kibo laboratory complex on the International Space Station. STS-127 is the 29th flight for the assembly of the space station. Photo credit: NASA/Analex

RELIABLE RADIOGRAPHIC INSPECTION OF FLEXIBLE RISERS FOR THE OIL INDUSTRY

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

Almeida, Romulo M.; Rebello, Joao Marcos A.; Vaz, Murilo A.

2010-02-22

Flexible risers are composite tubular structures manufactured by the concentric assemblage of cylindrical polymeric and helically wound metallic layers employed to convey pressurized fluids such as oil, gas and water in the ocean environment. The metallic layers account for the flexible risers' structural strength and are dimensioned according to the static and dynamic loads. They are usually installed in a free hanging catenary configuration and are subjected to the direct action of waves and marine currents and wave induced motions from the oil production platform. The fatigue rupture of wire armours in the end fitting or within the riser segmentmore » protected by the bend stiffener is an object of major concern. Integrity models have been developed, however inspection techniques are mandatory to ensure that failure is detected. Gammagraphy has been used as a common inspection technique in all regions of the flexible riser, mainly with the single wall-single view method. On the other side, there is not any qualified radiographic procedure to this kind of structure. Radiographic simulation was adopted and its validation with actual gammagraphies and establishment of radiographic parameters to complex radiation geometries were done. Results show the viability of the radiographic inspection analyzing the armour wires' rupture and the displacement between wires.« less

Reliable Radiographic Inspection of Flexible Risers for the Oil Industry

NASA Astrophysics Data System (ADS)

Almeida, Rômulo M.; Rebello, Joao Marcos A.; Vaz, Murilo A.

2010-02-01

Flexible risers are composite tubular structures manufactured by the concentric assemblage of cylindrical polymeric and helically wound metallic layers employed to convey pressurized fluids such as oil, gas and water in the ocean environment. The metallic layers account for the flexible risers' structural strength and are dimensioned according to the static and dynamic loads. They are usually installed in a free hanging catenary configuration and are subjected to the direct action of waves and marine currents and wave induced motions from the oil production platform. The fatigue rupture of wire armours in the end fitting or within the riser segment protected by the bend stiffener is an object of major concern. Integrity models have been developed, however inspection techniques are mandatory to ensure that failure is detected. Gammagraphy has been used as a common inspection technique in all regions of the flexible riser, mainly with the single wall-single view method. On the other side, there is not any qualified radiographic procedure to this kind of structure. Radiographic simulation was adopted and its validation with actual gammagraphies and establishment of radiographic parameters to complex radiation geometries were done. Results show the viability of the radiographic inspection analyzing the armour wires' rupture and the displacement between wires.

Comparison of optical and electrical measurements of the pantograph-catenary contact force

NASA Astrophysics Data System (ADS)

Bocciolone, Marco; Bucca, Giuseppe; Collina, Andrea; Comolli, Lorenzo

2010-09-01

In railway engineering the monitoring of contact force between pantograph and catenary gives information about the interaction between the two systems and it is useful to check the status of the overhead line. Indeed the failure of the catenary is one of the main causes of out of order problems. This study was conducted in a test campaign on an underground train instrumented with sensors able to monitor the line status. One of the more important measured quantities is the pantograph contact force, and two measurement systems were implemented: one optical and another electrical. The optical one was based on FBG sensors applied on the pantograph collector strip; the electrical one was based on two load cells positioned at the sides of the collector strip. The in-line measurements show that the optical solution is very promising, providing very reliable results that can be successfully used in the monitoring application, allowing the determination of the critical point in the line. The thermal compensation of any FBG sensors is a known problem and here is no exception: a thermal compensator was used to get also mean value measurements and the results are discussed.

Experimental and computational investigations on severe slugging in a catenary riser

NASA Astrophysics Data System (ADS)

Duan, Jin-long; Chen, Ke; You, Yun-xiang; Gao, Song

2017-12-01

Severe slugging can occur in a pipeline-riser system at relatively low liquid and gas flow rates during gas-oil transportation, possibly causing unexpected damage to the production facilities. Experiments with air and water are conducted in a horizontal and downward inclined pipeline followed by a catenary riser in order to investigate the mechanism and characteristics of severe slugging. A theoretical model is introduced to compare with the experiments. The results show that the formation mechanism of severe slugging in a catenary riser is different from that in a vertical riser due to the riser geometry and five flow patterns are obtained and analyzed. A gas-liquid mixture slug stage is observed at the beginning of one cycle of severe slugging, which is seldom noticed in previous studies. Based on both experiments and computations, the time period and variation of pressure amplitude of severe slugging are found closely related to the superficial gas velocity, implying that the gas velocity significantly influences the flow patterns in our experiments. Moreover, good agreements between the experimental data and the numerical results are shown in the stability curve and flow regime map, which can be a possible reference for design in an offshore oil-production system.

The Discrete Hanging Cable

ERIC Educational Resources Information Center

Peters, James V.

2004-01-01

Using the methods of finite difference equations the discrete analogue of the parabolic and catenary cable are analysed. The fibonacci numbers and the golden ratio arise in the treatment of the catenary.

Advanced mooring method for installation of Enserch Garden Banks 388 FPF mooring legs

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

Honig, H.J.; Koolwijk, W.; Scovell, D.C.

1995-12-31

In the fall of 1994 HeereMac v.o.f installed the 12 mooring legs for Enserch Exploration`s Floating Production Facility in Garden Banks Block 388 in the Gulf of Mexico with the SSCV Balder. The installation of the catenary mooring system, each leg comprising several varying sections of spiral strand wire and chain, required sufficient handling and maneuverability power of the vessel, while enough holding capacity and stiffness of the system had to be provided. The most important aspects of the actual installation of the mooring legs are explained, for example, the use of a purpose built tipping winch. The method selectedmore » by HeereMac for station-keeping the Balder was to use a minimum number of anchor lines in combination with a tug, in order to maintain position and at the same time have an easy and controlled method of maneuvering to a new position. The method of station-keeping the SSCV in this way is part of a development towards full position control with a spread of tugs. In this paper the station-keeping system is described and the offshore experiences with the system are discussed. Some future developments with respect to tug-assisted station-keeping systems are highlighted.« less

An amateur's contribution to the design of Telford's Menai Suspension Bridge: a commentary on Gilbert (1826) ‘On the mathematical theory of suspension bridges’

PubMed Central

Calladine, C. R.

2015-01-01

Davies Gilbert's work on the catenary is notable on two counts. First, it influenced Thomas Telford in formulating his final design for the Menai Strait suspension bridge (1826); and second, it established for the first time the form of the ‘catenary of equal strength’. The classical catenary is a uniform flexible chain or cable hanging freely under gravity between supports. The ‘catenary of equal strength’ is the form of a cable whose cross-sectional area is made proportional to the tension at each point, so that the tensile stress is uniform throughout. In this paper I provide a sketch of the lives and achievements of Gilbert and Telford, and of their interaction over the Menai Bridge. There follows a commentary on Gilbert's 1826 paper, and on his two related publications; and a brief sketch of the earlier history of the catenary. I then describe the development of the suspension bridge up to the present time. Finally, I discuss relations between mathematical analysts and practical engineers. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750153

An amateur's contribution to the design of Telford's Menai Suspension Bridge: a commentary on Gilbert (1826) 'On the mathematical theory of suspension bridges'.

PubMed

Calladine, C R

2015-04-13

Davies Gilbert's work on the catenary is notable on two counts. First, it influenced Thomas Telford in formulating his final design for the Menai Strait suspension bridge (1826); and second, it established for the first time the form of the 'catenary of equal strength'. The classical catenary is a uniform flexible chain or cable hanging freely under gravity between supports. The 'catenary of equal strength' is the form of a cable whose cross-sectional area is made proportional to the tension at each point, so that the tensile stress is uniform throughout. In this paper I provide a sketch of the lives and achievements of Gilbert and Telford, and of their interaction over the Menai Bridge. There follows a commentary on Gilbert's 1826 paper, and on his two related publications; and a brief sketch of the earlier history of the catenary. I then describe the development of the suspension bridge up to the present time. Finally, I discuss relations between mathematical analysts and practical engineers. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.

A fresh look at the catenary

NASA Astrophysics Data System (ADS)

Behroozi, F.

2014-09-01

A hanging chain takes the familiar form known as the catenary which is one of the most ubiquitous curves students encounter in their daily life. Yet most introductory physics and mathematics texts ignore the subject entirely. In more advanced texts the catenary equation is usually derived as an application of the calculus of variations. Although the variational approach is mathematically elegant, it is suitable for more advanced students. Here we derive the catenary equation in special and rectangular coordinates by considering the equilibrium conditions for an element of the hanging chain and without resorting to the calculus of variations. One advantage of this approach is its simplicity which makes it accessible to undergraduate students; another is the concurrent derivation of a companion equation which gives the tension along the chain. These solutions provide an excellent opportunity for undergraduates to explore the underlying physics. One interesting result is that the shape of a hanging chain does not depend on its linear mass density or on the strength of the gravitational field. Therefore, within a scale factor, all catenaries are copies of the same universal curve. We give the functional dependence of the scale factor on the length and terminal angle of the hanging chain.

Catenary optics for achromatic generation of perfect optical angular momentum

PubMed Central

Pu, Mingbo; Li, Xiong; Ma, Xiaoliang; Wang, Yanqin; Zhao, Zeyu; Wang, Changtao; Hu, Chenggang; Gao, Ping; Huang, Cheng; Ren, Haoran; Li, Xiangping; Qin, Fei; Yang, Jing; Gu, Min; Hong, Minghui; Luo, Xiangang

2015-01-01

The catenary is the curve that a free-hanging chain assumes under its own weight, and thought to be a “true mathematical and mechanical form” in architecture by Robert Hooke in the 1670s, with nevertheless no significant phenomena observed in optics. We show that the optical catenary can serve as a unique building block of metasurfaces to produce continuous and linear phase shift covering [0, 2π], a mission that is extremely difficult if not impossible for state-of-the-art technology. Via catenary arrays, planar optical devices are designed and experimentally characterized to generate various kinds of beams carrying orbital angular momentum (OAM). These devices can operate in an ultra-broadband spectrum because the anisotropic modes associated with the spin-orbit interaction are almost independent of the incident light frequency. By combining the optical and topological characteristics, our approach would allow the complete control of photons within a single nanometric layer. PMID:26601283

Diffusion of innovations dynamics, biological growth and catenary function

NASA Astrophysics Data System (ADS)

Guseo, Renato

2016-12-01

The catenary function has a well-known role in determining the shape of chains and cables supported at their ends under the force of gravity. This enables design using a specific static equilibrium over space. Its reflected version, the catenary arch, allows the construction of bridges and arches exploiting the dual equilibrium property under uniform compression. In this paper, we emphasize a further connection with well-known aggregate biological growth models over time and the related diffusion of innovation key paradigms (e.g., logistic and Bass distributions over time) that determine self-sustaining evolutionary growth dynamics in naturalistic and socio-economic contexts. Moreover, we prove that the 'local entropy function', related to a logistic distribution, is a catenary and vice versa. This special invariance may be explained, at a deeper level, through the Verlinde's conjecture on the origin of gravity as an effect of the entropic force.

Catenary optics for achromatic generation of perfect optical angular momentum.

PubMed

Pu, Mingbo; Li, Xiong; Ma, Xiaoliang; Wang, Yanqin; Zhao, Zeyu; Wang, Changtao; Hu, Chenggang; Gao, Ping; Huang, Cheng; Ren, Haoran; Li, Xiangping; Qin, Fei; Yang, Jing; Gu, Min; Hong, Minghui; Luo, Xiangang

2015-10-01

The catenary is the curve that a free-hanging chain assumes under its own weight, and thought to be a "true mathematical and mechanical form" in architecture by Robert Hooke in the 1670s, with nevertheless no significant phenomena observed in optics. We show that the optical catenary can serve as a unique building block of metasurfaces to produce continuous and linear phase shift covering [0, 2π], a mission that is extremely difficult if not impossible for state-of-the-art technology. Via catenary arrays, planar optical devices are designed and experimentally characterized to generate various kinds of beams carrying orbital angular momentum (OAM). These devices can operate in an ultra-broadband spectrum because the anisotropic modes associated with the spin-orbit interaction are almost independent of the incident light frequency. By combining the optical and topological characteristics, our approach would allow the complete control of photons within a single nanometric layer.

UNIDENTIFIED CATENARY SUSPENSION BRIDGE, SHOWING RIVETED METAL PIERS UNDER CONSTRUCTION. ...

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

UNIDENTIFIED CATENARY SUSPENSION BRIDGE, SHOWING RIVETED METAL PIERS UNDER CONSTRUCTION. NOTE APPROACH SPANS OF PIPE CONSTRUCTION IN RIGHT BACKGROUND. 3/4 VIEW FROM BELOW. - Clear Fork of Brazos River Suspension Bridge, Spanning Clear Fork of Brazos River at County Route 179, Albany, Shackelford County, TX

Coupled dynamics of a viscoelastically supported infinite string and a number of discrete mechanical systems moving with uniform speed

NASA Astrophysics Data System (ADS)

Roy, Soumyajit; Chakraborty, G.; DasGupta, Anirvan

2018-02-01

The mutual interaction between a number of multi degrees of freedom mechanical systems moving with uniform speed along an infinite taut string supported by a viscoelastic layer has been studied using the substructure synthesis method when base excitations of a common frequency are given to the mechanical systems. The mobility or impedance matrices of the string have been calculated analytically by Fourier transform method as well as wave propagation technique. The above matrices are used to calculate the response of the discrete mechanical systems. Special attention is paid to the contact forces between the discrete and the continuous systems which are estimated by numerical simulation. The effects of phase difference, the distance between the systems and different base excitation amplitudes on the collective behaviour of the mechanical systems are also studied. The present study has relevance to the coupled dynamic problem of more than one railway pantographs and an overhead catenary system where the pantographs are modelled as discrete systems and the catenary is modelled as a taut string supported by continuous viscoelastic layer.

Focus on Physics: The Delightful Catenary Curve

ERIC Educational Resources Information Center

Hewitt, Paul G.

2017-01-01

When teaching how "tension" and "compression" relate to geometrical structures such as bridges, arches, and domes, The author shows a picture of the Notre Dame Cathedral in Paris, completed in the 14th century, and presents a lesson on using the curve called a catenary to explain how he teaches about tension and compression…

NASA Manned Launch Vehicle Lightning Protection Development

NASA Technical Reports Server (NTRS)

McCollum, Matthew B.; Jones, Steven R.; Mack, Jonathan D.

2009-01-01

Historically, the National Aeronautics and Space Administration (NASA) relied heavily on lightning avoidance to protect launch vehicles and crew from lightning effects. As NASA transitions from the Space Shuttle to the new Constellation family of launch vehicles and spacecraft, NASA engineers are imposing design and construction standards on the spacecraft and launch vehicles to withstand both the direct and indirect effects of lightning. A review of current Space Shuttle lightning constraints and protection methodology will be presented, as well as a historical review of Space Shuttle lightning requirements and design. The Space Shuttle lightning requirements document, NSTS 07636, Lightning Protection, Test and Analysis Requirements, (originally published as document number JSC 07636, Lightning Protection Criteria Document) was developed in response to the Apollo 12 lightning event and other experiences with NASA and the Department of Defense launch vehicles. This document defined the lightning environment, vehicle protection requirements, and design guidelines for meeting the requirements. The criteria developed in JSC 07636 were a precursor to the Society of Automotive Engineers (SAE) lightning standards. These SAE standards, along with Radio Technical Commission for Aeronautics (RTCA) DO-160, Environmental Conditions and Test Procedures for Airborne Equipment, are the basis for the current Constellation lightning design requirements. The development and derivation of these requirements will be presented. As budget and schedule constraints hampered lightning protection design and verification efforts, the Space Shuttle elements waived the design requirements and relied on lightning avoidance in the form of launch commit criteria (LCC) constraints and a catenary wire system for lightning protection at the launch pads. A better understanding of the lightning environment has highlighted the vulnerability of the protection schemes and associated risk to the vehicle, which has resulted in lost launch opportunities and increased expenditures in manpower to assess Space Shuttle vehicle health and safety after lightning events at the launch pad. Because of high-percentage launch availability and long-term on-pad requirements, LCC constraints are no longer considered feasible. The Constellation vehicles must be designed to withstand direct and indirect effects of lightning. A review of the vehicle design and potential concerns will be presented as well as the new catenary lightning protection system for the launch pad. This system is required to protect the Constellation vehicles during launch processing when vehicle lightning effects protection might be compromised by such items as umbilical connections and open access hatches.

Variation in predicting pantograph-catenary interaction contact forces, numerical simulations and field measurements

NASA Astrophysics Data System (ADS)

Nåvik, Petter; Rønnquist, Anders; Stichel, Sebastian

2017-09-01

The contact force between the pantograph and the contact wire ensures energy transfer between the two. Too small of a force leads to arching and unstable energy transfer, while too large of a force leads to unnecessary wear on both parts. Thus, obtaining the correct contact force is important for both field measurements and estimates using numerical analysis. The field contact force time series is derived from measurements performed by a self-propelled diagnostic vehicle containing overhead line recording equipment. The measurements are not sampled at the actual contact surface of the interaction but by force transducers beneath the collector strips. Methods exist for obtaining more realistic measurements by adding inertia and aerodynamic effects to the measurements. The variation in predicting the pantograph-catenary interaction contact force is studied in this paper by evaluating the effect of the force sampling location and the effects of signal processing such as filtering. A numerical model validated by field measurements is used to study these effects. First, this paper shows that the numerical model can reproduce a train passage with high accuracy. Second, this study introduces three different options for contact force predictions from numerical simulations. Third, this paper demonstrates that the standard deviation and the maximum and minimum values of the contact force are sensitive to a low-pass filter. For a specific case, an 80 Hz cut-off frequency is compared to a 20 Hz cut-off frequency, as required by EN 50317:2012; the results show an 11% increase in standard deviation, a 36% increase in the maximum value and a 19% decrease in the minimum value.

Catenary-induced geometric nonlinearity effects on cable linear vibrations

NASA Astrophysics Data System (ADS)

Mansour, Achref; Mekki, Othman Ben; Montassar, Sami; Rega, Giuseppe

2018-01-01

This paper investigates the free undamped vibrations of cables of arbitrary sag and inclination according to the catenary theory. The proposed approach accounts for the catenary effect on the static profile around which the cable motion is defined. Considering first order geometric nonlinearities, exact expression of the curvature is obtained along with the ensuing correction of the well known Irvine parameter. Taking into account the new characterization, different regions of shallow and non-shallow profiles are identified for various inclinations. In view of such classification, the analysis carried out on cable linear modal properties shows the emergence of new dynamic features such as additional hybrid modes and internal resonances. Analytical and numerical results reduce to those obtained by classic formulations in the cases of both horizontal and inclined shallow/non-shallow cables.

49 CFR 611.105 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... public transportation and other high occupancy vehicles, or uses a fixed catenary system and a right of... rail, commuter rail, automated guideway transit, people movers, ferry boat service, and fixed-guideway facilities for buses (such as bus rapid transit) and other high occupancy vehicles. A new fixed guideway...

49 CFR 611.105 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... public transportation and other high occupancy vehicles, or uses a fixed catenary system and a right of... rail, commuter rail, automated guideway transit, people movers, ferry boat service, and fixed-guideway facilities for buses (such as bus rapid transit) and other high occupancy vehicles. A new fixed guideway...

Solar radiation on a catenary collector

NASA Technical Reports Server (NTRS)

Crutchik, M.; Appelbaum, J.

1992-01-01

A tent-shaped structure with a flexible photovoltaic blanket acting as a catenary collector is presented. The shadow cast by one side of the collector produces a shadow on the other side of the collector. This self-shading effect is analyzed. The direct beam, the diffuse, and the albedo radiation on the collector are determined. An example is given for the insolation on the collector operating on Viking Lander 1 (VL1).

1. General view, east end and north side. View to ...

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

1. General view, east end and north side. View to southwest toward San Francisco-Oakland Bay Bridge, along general alignment of former Interurban Electric Railway main line. Note truncated catenary support arms on power poles; these originally carried overhead power supply catenary line for the electrically-powered interurban cars. - Interurban Electric Railway Bridge Yard Shop, Interstate 80 at Alameda County Postmile 2.0, Oakland, Alameda County, CA

Design of a radiator shade for testing in a simulated lunar environment

NASA Technical Reports Server (NTRS)

Huff, Jaimi; Remington, Randy; Tang, Toan

1992-01-01

The National Aeronautics and Space Administration (NASA) and The Universities Space Research Association (USRA) have chosen the parabolic/catenary concept from their sponsored Fall 1991 lunar radiation shade project for further testing and development. NASA asked the design team to build a shading device and support structure for testing in a vacuum chamber. Besides the support structure for the catenary shading device, the design team was asked to develop a system for varying the shade shape so that the device can be tested at different focal lengths. The design team developed concept variants and combined the concept variants to form overall designs. Using a decision matrix, an overall design was selected by the team from several overall design alternatives. Concept variants were developed for three primary functions. The three functions were structural support, shape adjustments, and end shielding. The shade adjustment function was divided into two sub-functions, arc length adjustment, and width adjustment.

Catenaries in Drag

NASA Astrophysics Data System (ADS)

Chakrabarti, Brato; Hanna, James

2014-11-01

Dynamical equilibria of towed cables and sedimenting filaments have been the targets of much numerical work; here, we provide analytical expressions for the configurations of a translating and axially moving string subjected to a uniform body force and local, linear, anisotropic drag forces. Generically, these configurations comprise a five-parameter family of planar shapes determined by the ratio of tangential (axial) and normal drag coefficients, the angle between the translational velocity and the body force, the relative magnitudes of translational and axial drag forces with respect to the body force, and a scaling parameter. This five-parameter family of shapes is, in fact, a degenerate six-parameter family of equilibria in which inertial forces rescale the tension in the string without affecting its shape. Each configuration is represented by a first order dynamical system for the tangential angle of the body. Limiting cases include the dynamic catenaries with or without drag, and purely sedimenting or towed strings.

Solar radiation on a catenary collector

NASA Technical Reports Server (NTRS)

Crutchik, M.; Appelbaum, J.

1992-01-01

A tent-shaped structure with a flexible photovoltaic blanket acting as a catenary collector is presented. The shadow cast by one side of the collector on the other side producing a self shading effect is analyzed. The direct beam, the diffuse and the albedo radiation on the collector are determined. An example is given for the insolation on the collector operating on the martian surface for the location of Viking Lander 1 (VL1).

UNIDENTIFIED CATENARY SUSPENSION BRIDGE ON RIVETED METAL PIERS, SHOWING HOWE ...

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

UNIDENTIFIED CATENARY SUSPENSION BRIDGE ON RIVETED METAL PIERS, SHOWING HOWE PIPE TRUSS RAILING AND TRUSSED DECK BEAMS TYPICAL TO BRIDGES BUILT BY FLINN-MOYER COMPANY. TRIPODAL PIPE TOWERS RESEMBLE CLEAR FORK OF THE BRAZOS SUSPENSION BRIDGE’S TOWERS PRIOR TO ENCASEMENT IN CONCRETE. NOTE COLLAPSED TRUSS IN RIVER. ELEVATION VIEW. - Clear Fork of Brazos River Suspension Bridge, Spanning Clear Fork of Brazos River at County Route 179, Albany, Shackelford County, TX

Feasibility of Floating Platform Systems for Wind Turbines: Preprint

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

Musial, W.; Butterfield, S.; Boone, A.

This paper provides a general technical description of several types of floating platforms for wind turbines. Platform topologies are classified into multiple- or single-turbine floaters and by mooring method. Platforms using catenary mooring systems are contrasted to vertical mooring systems and the advantages and disadvantages are discussed. Specific anchor types are described in detail. A rough cost comparison is performed for two different platform architectures using a generic 5-MW wind turbine. One platform is a Dutch study of a tri-floater platform using a catenary mooring system, and the other is a mono-column tension-leg platform developed at the National Renewable Energymore » Laboratory. Cost estimates showed that single unit production cost is $7.1 M for the Dutch tri-floater, and $6.5 M for the NREL TLP concept. However, value engineering, multiple unit series production, and platform/turbine system optimization can lower the unit platform costs to $4.26 M and $2.88 M, respectively, with significant potential to reduce cost further with system optimization. These foundation costs are within the range necessary to bring the cost of energy down to the DOE target range of $0.05/kWh for large-scale deployment of offshore floating wind turbines.« less

Mechanical design of NASA Ames Research Center vertical motion simulator

NASA Technical Reports Server (NTRS)

Engelbert, D. F.; Bakke, A. P.; Chargin, M. K.; Vallotton, W. C.

1976-01-01

NASA has designed and is constructing a new flight simulator with large vertical travel. Several aspects of the mechanical design of this Vertical Motion Simulator (VMS) are discussed, including the multiple rack and pinion vertical drive, a pneumatic equilibration system, and the friction-damped rigid link catenaries used as cable supports.

Simulation study on electric field intensity above train roof

NASA Astrophysics Data System (ADS)

Fan, Yizhe; Li, Huawei; Yang, Shasha

2018-04-01

In order to understand the distribution of electric field in the space above the train roof accurately and select the installation position of the detection device reasonably, in this paper, the 3D model of pantograph-catenary is established by using SolidWorks software, and the spatial electric field distribution of pantograph-catenary model is simulated based on Comsol software. According to the electric field intensity analysis within the 0.4m space above train roof, we give a reasonable installation of the detection device.

Wideband analysis of railway catenary line radiation and new applications of its unintentional emitted signals

NASA Astrophysics Data System (ADS)

Heddebaut, Marc; Deniau, Virginie; Rioult, Jean

2018-06-01

Generally, in railway networks, dissipated energy—and its consequences in terms of noise, ballast attrition, electromagnetic interference, etc—is considered a nuisance generated by this means of transport. Therefore, most studies are carried out with the aim of reducing it. This paper takes the opposite view and considers the particular case of the irreducible electromagnetic interference generated along an electrified line, in order to propose new applications beneficial to railway operations. At a selected representative location, wideband (ranging from 10 kHz to 1 GHz) electromagnetic field measurements are performed successively during, and not during, high speed train passages. We deduce two potential applications of these unintentional signals. At low frequency, the first proposal considers energy harvesting using the received electromagnetic interference as the source. This received energy can be converted and used to DC feed low consumption sensors to be installed along the railway infrastructure. These sensors participate in monitoring infrastructure health and in making it more resilient to internal and external stresses. At higher frequencies, for the second proposal, radiation from the catenary line and train pantograph is specifically examined at a carefully selected sub-band. The results are also studied following a time–frequency analysis, to introduce a new nondestructive inspection method of the sliding contact between the catenary line and the train pantograph. Ultimately, this technique could offer a new means of monitoring the health of both the catenary line and the pantograph.

1. PERSPECTIVE VIEW FROM NORTHWEST OF NORTH SIDE. LOW BUILDING ...

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

1. PERSPECTIVE VIEW FROM NORTHWEST OF NORTH SIDE. LOW BUILDING IN CENTER IS A SIGNAL POWER GENERATING STATION (C. 1986). LOW TOWER STRUCTURE ON THE LEFT IS ANCHOR BRIDGE NUMBER 310, LOCATION OF POWER FEED TO THE CATENARY SYSTEM. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

KSC-06pd0071

NASA Image and Video Library

2006-01-16

KENNEDY SPACE CENTER, FLA. - With the backdrop of blue sky and blue water of the Atlantic Ocean, the Atlas V expendable launch vehicle with the New Horizons spacecraft (center) is nearly ready for launch. Surrounding the rocket are lightning masts that support the catenary wire used to provide lightning protection. The liftoff is scheduled for 1:24 p.m. EST Jan. 17. After its launch aboard the Atlas V, the compact, 1,050-pound piano-sized probe will get a boost from a kick-stage solid propellant motor for its journey to Pluto. New Horizons will be the fastest spacecraft ever launched, reaching lunar orbit distance in just nine hours and passing Jupiter 13 months later. The New Horizons science payload, developed under direction of Southwest Research Institute, includes imaging infrared and ultraviolet spectrometers, a multi-color camera, a long-range telescopic camera, two particle spectrometers, a space-dust detector and a radio science experiment. The dust counter was designed and built by students at the University of Colorado, Boulder. A launch before Feb. 3 allows New Horizons to fly past Jupiter in early 2007 and use the planet’s gravity as a slingshot toward Pluto. The Jupiter flyby trims the trip to Pluto by as many as five years and provides opportunities to test the spacecraft’s instruments and flyby capabilities on the Jupiter system. New Horizons could reach the Pluto system as early as mid-2015, conducting a five-month-long study possible only from the close-up vantage of a spacecraft.

KSC-06pd0069

NASA Image and Video Library

2006-01-16

KENNEDY SPACE CENTER, FLA. - On Complex 41 at Cape Canaveral Air Force Station, the Atlas V expendable launch vehicle with the New Horizons spacecraft has been moved to the pad. Umbilicals have been attached. Seen near the rocket are lightning masts that support the catenary wire used to provide lightning protection. Liftoff is scheduled for 1:24 p.m. EST Jan. 17. After its launch aboard the Atlas V, the compact, 1,050-pound piano-sized probe will get a boost from a kick-stage solid propellant motor for its journey to Pluto. New Horizons will be the fastest spacecraft ever launched, reaching lunar orbit distance in just nine hours and passing Jupiter 13 months later. The New Horizons science payload, developed under direction of Southwest Research Institute, includes imaging infrared and ultraviolet spectrometers, a multi-color camera, a long-range telescopic camera, two particle spectrometers, a space-dust detector and a radio science experiment. The dust counter was designed and built by students at the University of Colorado, Boulder. A launch before Feb. 3 allows New Horizons to fly past Jupiter in early 2007 and use the planet’s gravity as a slingshot toward Pluto. The Jupiter flyby trims the trip to Pluto by as many as five years and provides opportunities to test the spacecraft’s instruments and flyby capabilities on the Jupiter system. New Horizons could reach the Pluto system as early as mid-2015, conducting a five-month-long study possible only from the close-up vantage of a spacecraft.

Catenaries in viscous fluid

NASA Astrophysics Data System (ADS)

Hanna, James; Chakrabarti, Brato

2015-11-01

Slender structures live in fluid flows across many scales, from towed instruments to plant blades to microfluidic valves. The present work details a simple model of a flexible structure in a uniform flow. We present analytical solutions for the translating, axially flowing equilibria of strings subjected to a uniform body force and linear drag forces. This is an extension of the classical catenaries to a five-parameter family of solutions, represented as trajectories in angle-curvature ``phase space.'' Limiting cases include neutrally buoyant towed cables and freely sedimenting flexible filaments. Now at University of California, San Diego.

Development and Sensing Properties Study of Underwater Assembled Water Depth-Inclination Sensors for a Multi-Component Mooring System, Using a Self-Contained Technique

PubMed Central

Wu, Wenhua; Feng, Jiaguo; Xie, Bin; Tang, Da; Yue, Qianjin; Xie, Ribin

2016-01-01

Prototype monitoring techniques play an important role in the safety guarantee of mooring systems in marine engineering. In general, the complexities of harsh ocean environmental conditions bring difficulties to the traditional monitoring methods of application, implementation and maintenance. Large amounts of existing mooring systems still lack valid monitoring strategies. In this paper, an underwater monitoring method which may be used to achieve the mechanical responses of a multi-point catenary mooring system, is present. A novel self-contained assembled water depth-inclination (D-I) sensor is designed and manufactured. Several advanced technologies, such as standalone, low power consumption and synchronism, are considered to satisfy the long-term implementation requirements with low cost during the design process. The design scheme of the water resistance barrel and installation clamp, which satisfies the diver installation, are also provided in the paper. An on-site test has previously been carried out on a production semisubmersible platform in the South China Sea. The prototype data analyses, including the D-I value in the time domain (including the data recorded during the mooring retraction and release process) and spectral characteristics, are presented to reveal the accuracy, feasibility and stability of the sensor in terms of fitting for the prototype monitoring of catenary mooring systems, especially for in-service aging platforms. PMID:27854357

A physiology-based parametric imaging method for FDG-PET data

NASA Astrophysics Data System (ADS)

Scussolini, Mara; Garbarino, Sara; Sambuceti, Gianmario; Caviglia, Giacomo; Piana, Michele

2017-12-01

Parametric imaging is a compartmental approach that processes nuclear imaging data to estimate the spatial distribution of the kinetic parameters governing tracer flow. The present paper proposes a novel and efficient computational method for parametric imaging which is potentially applicable to several compartmental models of diverse complexity and which is effective in the determination of the parametric maps of all kinetic coefficients. We consider applications to [18 F]-fluorodeoxyglucose positron emission tomography (FDG-PET) data and analyze the two-compartment catenary model describing the standard FDG metabolization by an homogeneous tissue and the three-compartment non-catenary model representing the renal physiology. We show uniqueness theorems for both models. The proposed imaging method starts from the reconstructed FDG-PET images of tracer concentration and preliminarily applies image processing algorithms for noise reduction and image segmentation. The optimization procedure solves pixel-wise the non-linear inverse problem of determining the kinetic parameters from dynamic concentration data through a regularized Gauss-Newton iterative algorithm. The reliability of the method is validated against synthetic data, for the two-compartment system, and experimental real data of murine models, for the renal three-compartment system.

A photovoltaic catenary-tent array for the Martian surface

NASA Technical Reports Server (NTRS)

Crutchik, M.; Colozza, Anthony J.; Appelbaum, J.

1993-01-01

To provide electrical power during an exploration mission to Mars, a deployable tent-shaped structure with a flexible photovoltaic (PV) blanket is proposed. The array is designed with a self-deploying mechanism utilizing pressurized gas expansion. The structural design for the array uses a combination of cables, beams, and columns to support and deploy the PV blanket. Under the force of gravity a cable carrying a uniform load will take the shape of a catenary curve. A catenary-tent collector is self shadowing which must be taken into account in the solar radiation calculation. The shape and the area of the shadow on the array was calculated and used in the determination of the global radiation on the array. The PV blanket shape and structure dimension were optimized to achieve a configuration which maximizes the specific power (W/kg). The optimization was performed for four types of PV blankets (Si, GaAs/Ge, GaAs CLEFT, and amorphous Si) and four types of structure materials (Carbon composite, Aramid Fiber composite, Aluminum, and Magnesium). The results show that the catenary shape of the PV blanket, which produces the highest specific power, corresponds to zero end angle at the base with respect to the horizontal. The tent angle is determined by the combined effect of the array structure specific mass and the PV blanket output power. The combination of carbon composite structural material and GaAs CLEFT solar cells produce the highest specific power. The study was carried out for two sites on Mars corresponding to the Viking Lander locations. The designs were also compared for summer, winter, and yearly operation.

Theoretical performance of cross-wind axis turbines with results for a catenary vertical axis configuration

NASA Technical Reports Server (NTRS)

Muraca, R. J.; Stephens, M. V.; Dagenhart, J. R.

1975-01-01

A general analysis capable of predicting performance characteristics of cross-wind axis turbines was developed, including the effects of airfoil geometry, support struts, blade aspect ratio, windmill solidity, blade interference and curved flow. The results were compared with available wind tunnel results for a catenary blade shape. A theoretical performance curve for an aerodynamically efficient straight blade configuration was also presented. In addition, a linearized analytical solution applicable for straight configurations was developed. A listing of the computer program developed for numerical solutions of the general performance equations is included in the appendix.

Evaluation of the Performance Characteristics of the CGLSS and NLDN Systems Based on Two Years of Ground-Truth Data from Launch Complex 39B, Kennedy Space Center, Florida

NASA Technical Reports Server (NTRS)

Mata, Carlos T.; Hill, Jonathan D.; Mata, Angel G.; Cummins, Kenneth L.

2014-01-01

From May 2011 through July 2013, the lightning instrumentation at Launch Complex 39B (LC39B) at the Kennedy Space Center, Florida, has obtained high-speed video records and field change waveforms (dE/dt and three-axis dH/dt) for 54 negative polarity return strokes whose strike termination locations and times are known with accuracy of the order of 10 m or less and 1 µs, respectively. A total of 18 strokes terminated directly to the LC39B lighting protection system (LPS), which contains three 181 m towers in a triangular configuration, an overhead catenary wire system on insulating masts, and nine down conductors. An additional 9 strokes terminated on the 106 m lightning protection mast of Launch Complex 39A (LC39A), which is located about 2.7 km southeast of LC39B. The remaining 27 return strokes struck either on the ground or attached to low-elevation grounded objects within about 500 m of the LC39B LPS. Leader/return stroke sequences were imaged at 3200 frames/sec by a network of six Phantom V310 high-speed video cameras. Each of the three towers on LC39B had two high-speed cameras installed at the 147 m level with overlapping fields of view of the center of the pad. The locations of the strike points of 54 return strokes have been compared to time-correlated reports of the Cloud-to-Ground Lightning Surveillance System (CGLSS) and the National Lightning Detection Network (NLDN), and the results of this comparison will be presented and discussed.

Pantograph-catenary monitoring by means of fibre Bragg grating sensors: Results from tests in an underground line

NASA Astrophysics Data System (ADS)

Bocciolone, Marco; Bucca, Giuseppe; Collina, Andrea; Comolli, Lorenzo

2013-12-01

One of the most common way to collect the traction current needed for the underground vehicle operation is by using the pantograph-overhead line system. The periodically check of pantographs and overhead lines is important to assure the correct interaction between the two systems in terms of good current collection quality. The main diagnostic tools are the monitoring of the vertical force between the overhead line and the pantograph head, and the vertical acceleration on the pantograph head. The pantograph system works under high voltage (1500 V, DC, in our tests) and high electromagnetic disturbances are present. For this reason, traditional electrical sensors can be used only with particular precautions that complicate the measurement set up; fibre optic sensors, and in particular fibre Bragg grating (FBG) sensors, are particularly suitable for this application. In this paper, the application of the FBG sensors on a pantograph for the monitoring of underground pantograph-catenary system is presented. FBG sensors are used to measure both the contact force and the vertical acceleration of the pantograph head. The same measurements are also gathered with a traditional electrical system, allowing a comparison. The result is a very good agreement between electrical and optical measurements, except in particular frequency ranges where the different positioning of the sensors influences the output, limiting the comparison. Moreover, some interesting results on the dynamic behaviour of the pantograph and its interaction with the overhead line are presented. Finally, a method to point out the main defects on the overhead line is shown.

View northeast of a microchip based computer control system installed ...

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

View northeast of a microchip based computer control system installed in the early 1980's to replace Lamokin Tower, at center of photograph; panels 1 and 2 at right of photograph are part of main supervisory board; panel 1 controlled Allen Lane sub-station #7; responsiblity for this portion of the system was transferred to southeast Pennsylvania transit authority (septa) in 1985; panel 2 at extreme right controls catenary switches in a coach storage yard adjacent to the station - Thirtieth Street Station, Power Director Center, Thirtieth & Market Streets in Amtrak Railroad Station, Philadelphia, Philadelphia County, PA

Adaptive neuro fuzzy system for modelling and prediction of distance pantograph catenary in railway transportation

NASA Astrophysics Data System (ADS)

Panoiu, M.; Panoiu, C.; Lihaciu, I. L.

2018-01-01

This research presents an adaptive neuro-fuzzy system which is used in the prediction of the distance between the pantograph and contact line of the electrical locomotives used in railway transportation. In railway transportation any incident that occurs in the electrical system can have major negative effects: traffic interrupts, equipment destroying. Therefore, a prediction as good as possible of such situations is very useful. In the paper was analyzing the possibility of modeling and prediction the variation of the distance between the pantograph and the contact line using intelligent techniques

Improvement of automatic control system for high-speed current collectors

NASA Astrophysics Data System (ADS)

Sidorov, O. A.; Goryunov, V. N.; Golubkov, A. S.

2018-01-01

The article considers the ways of regulation of pantographs to provide quality and reliability of current collection at high speeds. To assess impact of regulation was proposed integral criterion of the quality of current collection, taking into account efficiency and reliability of operation of the pantograph. The study was carried out using mathematical model of interaction of pantograph and catenary system, allowing to assess contact force and intensity of arcing at the contact zone at different movement speeds. The simulation results allowed us to estimate the efficiency of different methods of regulation of pantographs and determine the best option.

Summary of JIP

DOT National Transportation Integrated Search

2008-04-01

The SCRIM (Steel Catenary Riser Integrity Management) Joint Industry Project was an industry-sponsored initiative, managed and delivered by MCS, to develop industry guidelines for the integrity management of offshore risers. The original scope of the...

30 CFR 250.907 - Where must I locate foundation boreholes?

Code of Federal Regulations, 2014 CFR

2014-07-01

... soil boring must not exceed 500 feet. (b) For deepwater floating platforms which utilize catenary or..., other points throughout the anchor pattern to establish the soil profile suitable for foundation design...

30 CFR 250.907 - Where must I locate foundation boreholes?

Code of Federal Regulations, 2013 CFR

2013-07-01

... soil boring must not exceed 500 feet. (b) For deepwater floating platforms which utilize catenary or..., other points throughout the anchor pattern to establish the soil profile suitable for foundation design...

30 CFR 250.907 - Where must I locate foundation boreholes?

Code of Federal Regulations, 2012 CFR

2012-07-01

... soil boring must not exceed 500 feet. (b) For deepwater floating platforms which utilize catenary or..., other points throughout the anchor pattern to establish the soil profile suitable for foundation design...

Identification and location of catenary insulator in complex background based on machine vision

NASA Astrophysics Data System (ADS)

Yao, Xiaotong; Pan, Yingli; Liu, Li; Cheng, Xiao

2018-04-01

It is an important premise to locate insulator precisely for fault detection. Current location algorithms for insulator under catenary checking images are not accurate, a target recognition and localization method based on binocular vision combined with SURF features is proposed. First of all, because of the location of the insulator in complex environment, using SURF features to achieve the coarse positioning of target recognition; then Using binocular vision principle to calculate the 3D coordinates of the object which has been coarsely located, realization of target object recognition and fine location; Finally, Finally, the key is to preserve the 3D coordinate of the object's center of mass, transfer to the inspection robot to control the detection position of the robot. Experimental results demonstrate that the proposed method has better recognition efficiency and accuracy, can successfully identify the target and has a define application value.

The fall of a viscous thread onto a moving surface: a ‘fluid-mechanical sewing machine’

NASA Astrophysics Data System (ADS)

Chiu-Webster, S.; Lister, J. R.

2006-12-01

A viscous thread falling onto a steadily moving horizontal belt shows a surprisingly complex range of behaviour in experiments. Low belt speeds produce coiling, as might be expected from the behaviour of a thread falling onto a stationary surface. High belt speeds produce a steady thread, whose shape is predicted well by theory developed to describe a stretching viscous catenary with surface tension and inertia. Intermediate belt speeds show several novel modes of oscillation, which lay down a wide variety of patterns on the belt. The patterns include meanders, side kicks, slanted loops, braiding, figures-of-eight, Ws, and also period-doubled versions of figures-of-eight, meanders and coiling. The experimental boundary between steady and unsteady behaviour occurs at a slightly lower belt speed than the loss of the steady solution for a stretching catenary.

Influence of bolt tightening torque, wire size, and component reuse on wire fixation in circular external fixation.

PubMed

Wosar, Marc A; Marcellin-Little, Denis J; Roe, Simon C

2002-01-01

To evaluate the effects of bolt torque, wire size, and component reuse on the ability to maintain wire tension in 3 external skeletal fixation systems. Biomechanical study. Yield strength in tension of 1.0-, 1.2-, 1.5-, and 1.6-mm-diameter wires, and yield strength in torque of Hofmann Small Bone Fixation (SBF) cannulated and slotted bolts and IMEX regular and miniature bolts were determined on a testing machine. The minimum bolt tightening torque needed to prevent wire slippage at clinically recommended wire tensions was determined. Components were tested 10 times, and loads at slippage were recorded. The IMEX system required a mean of 8 Nm of bolt tightening torque to maintain 900 N (1.6-mm wires). The SBF system required a mean of 3 Nm bolt torque to maintain 300 N (1.0-mm wires) and 5 Nm to maintain 600 N (1.2-mm wires). The SBF cannulated bolt required 9 Nm of torque to maintain 900 N (1.5-mm wires). The SBF slotted bolts could only maintain 800 N before yield. The IMEX miniature system required a mean bolt torque of 1.1 Nm to maintain 300 N. The cannulated and slotted bolts from both manufacturers failed to maintain 70% of initial wire tension after 7 and 4 uses, respectively. The IMEX systems and the SBF system using 1.0- and 1.2-mm wires could maintain clinically recommended wire tension safely. Only the IMEX system could maintain clinically recommended wire tension safely using 1.5- or 1.6-mm wires. The SBF system using 1.0- and 1.2-mm wires and the IMEX system using all wire sizes can maintain clinically relevant wire tension. The SBF system using 1.5-mm wires could not. Cannulated and slotted bolts should not be used more than 6 and 3 times, respectively. Nuts should not be reused. Copyright 2002 by The American College of Veterinary Surgeons

Model-Based Testability Assessment and Directed Troubleshooting of Shuttle Wiring Systems

NASA Technical Reports Server (NTRS)

Deb, Somnath; Domagala, Chuck; Shrestha, Roshan; Malepati, Venkatesh; Cavanaugh, Kevin; Patterson-Hine, Ann; Sanderfer, Dwight; Cockrell, Jim; Norvig, Peter (Technical Monitor)

2000-01-01

We have recently completed a pilot study on the Space shuttle wiring system commissioned by the Wiring Integrity Research (WIRe) team at NASA Ames Research Center, As the space shuttle ages, it is experiencing wiring degradation problems including arcing, chaffing insulation breakdown and broken conductors. A systematic and comprehensive test process is required to thoroughly test and quality assure (QA) the wiring systems. The NASA WIRe team recognized the value of a formal model based analysis for risk-assessment and fault coverage analysis. However. wiring systems are complex and involve over 50,000 wire segments. Therefore, NASA commissioned this pilot study with Qualtech Systems. Inc. (QSI) to explore means of automatically extracting high fidelity multi-signal models from wiring information database for use with QSI's Testability Engineering and Maintenance System (TEAMS) tool.

A review of wiring system safety in space power systems

NASA Technical Reports Server (NTRS)

Stavnes, Mark W.; Hammoud, Ahmad N.

1993-01-01

Wiring system failures have resulted from arc propagation in the wiring harnesses of current aerospace vehicles. These failures occur when the insulation becomes conductive upon the initiation of an arc. In some cases, the conductive path of the carbon arc track displays a high enough resistance such that the current is limited, and therefore may be difficult to detect using conventional circuit protection. Often, such wiring failures are not simply the result of insulation failure, but are due to a combination of wiring system factors. Inadequate circuit protection, unforgiving system designs, and careless maintenance procedures can contribute to a wiring system failure. This paper approaches the problem with respect to the overall wiring system, in order to determine what steps can be taken to improve the reliability, maintainability, and safety of space power systems. Power system technologies, system designs, and maintenance procedures which have led to past wiring system failures will be discussed. New technologies, design processes, and management techniques which may lead to improved wiring system safety will be introduced.

Autonomous diagnostics and prognostics of signal and data distribution systems

NASA Astrophysics Data System (ADS)

Blemel, Kenneth G.

2001-07-01

Wiring is the nervous system of any complex system and is attached to or services nearly every subsystem. Damage to optical wiring systems can cause serious interruptions in communication, command and control systems. Electrical wiring faults and failures due to opens, shorts, and arcing probably result in adverse effects to the systems serviced by the wiring. Abnormalities in a system usually can be detected by monitoring some wiring parameter such as vibration, data activity or power consumption. This paper introduces the mapping of wiring to critical functions during system engineering to automatically define the Failure Modes Effects and Criticality Analysis. This mapping can be used to define the sensory processes needed to perform diagnostics during system engineering. This paper also explains the use of Operational Modes and Criticality Effects Analysis in the development of Sentient Wiring Systems as a means for diagnostic, prognostics and health management of wiring in aerospace and transportation systems.

Vibration characteristics of an inclined flip-flow screen panel in banana flip-flow screens

NASA Astrophysics Data System (ADS)

Xiong, Xiaoyan; Niu, Linkai; Gu, Chengxiang; Wang, Yinhua

2017-12-01

A banana flip-flow screen is an effective solution for the screening of high-viscosity, high-water and fine materials. As one of the key components, the vibration characteristics of the inclined flip-flow screen panel largely affects the screen performance and the processing capacity. In this paper, a mathematical model for the vibration characteristic of the inclined flip-flow screen panel is proposed based on Catenary theory. The reasonability of Catenary theory in analyzing the vibration characteristic of flip-flow screen panels is verified by a published experiment. Moreover, the effects of the rotation speed of exciters, the incline angle, the slack length and the characteristics of the screen on the vertical deflection, the vertical velocity and the vertical acceleration of the screen panel are investigated parametrically. The results show that the rotation speed of exciters, the incline angle, the slack length and the characteristics of the screen have significant effects on the vibrations of an inclined flip-flow screen panel, and these parameters should be optimized.

Solar concentrator

NASA Technical Reports Server (NTRS)

Simpson, J. G. (Inventor)

1979-01-01

An improved solar concentrator is characterized by a number of elongated supporting members arranged in substantial horizontal parallelism with the axis and intersecting a common curve. A tensioned sheet of flexible reflective material is disposed in engaging relation with the supporting members in order to impart to the tensioned sheet a catenary configuration.

Equivalent model and power flow model for electric railway traction network

NASA Astrophysics Data System (ADS)

Wang, Feng

2018-05-01

An equivalent model of the Cable Traction Network (CTN) considering the distributed capacitance effect of the cable system is proposed. The model can be divided into 110kV side and 27.5kV side two kinds. The 110kV side equivalent model can be used to calculate the power supply capacity of the CTN. The 27.5kV side equivalent model can be used to solve the voltage of the catenary. Based on the equivalent simplified model of CTN, the power flow model of CTN which involves the reactive power compensation coefficient and the interaction of voltage and current, is derived.

Design of Buoys for Mounting Wind Turbines at Exposed Sites

NASA Astrophysics Data System (ADS)

Erdoğan, Beytullah; Çelıkkol, Barbaros; Swift, Robinson

2018-04-01

In this study, two designs for a buoy capable of supporting a 10 kW wind turbine and its tower were developed to operate at the University of New Hampshire's Center of Ocean Renewable Energy testing site located off the Isles of Shoals, New Hampshire. The buoys are to be moored by a catenary chain system. To evaluate wave response, two Froude-scaled models were constructed, tested, and compared at the Ocean Engineering wave tank at the University of New Hampshire. These buoys have been implemented and compared with wave tank measurements of the spar displacement at a reference elevation 2.44 m above the mean water level.

Christiaan Huygens and the Problem of the Hanging Chain

ERIC Educational Resources Information Center

Bukowski, John F.

2008-01-01

The seventeen-year-old Christiaan Huygens was the first to prove that a hanging chain did not take the form of the parabola, as was commonly thought in the early seventeenth century. We will examine Huygen's geometrical proof, and we will investigate the later history of the catenary.

Photovoltaic system with improved AC connections and method of making same

DOEpatents

Cioffi, Philip Michael; Todorovic, Maja Harfman; Herzog, Michael Scott; Korman, Charles Steven; Doherty, Donald M.; Johnson, Neil Anthony

2018-02-13

An alternating current (AC) harness for a photovoltaic (PV) system includes a wire assembly having a first end and a second end, the wire assembly having a plurality of lead wires, and at least one AC connection module positioned at a location along a length of the wire assembly between the first end and the second end. Further, the at least one AC connection module includes a first connection terminal electrically coupled to the plurality of lead wires of the wire assembly and constructed to electrically couple the wire assembly with an output of a first PV module of the PV system. The at least one AC connection module also includes a second connection terminal electrically coupled to the plurality of lead wires of the wire assembly and constructed to electrically couple the wire assembly with an output of a second PV module of the PV system.

Multicenter comparative trial of the V-scope system for therapeutic ERCP.

PubMed

Joyce, A M; Ahmad, N A; Beilstein, M C; Kochman, M L; Long, W B; Baron, T; Sherman, S; Fogel, E; Lehman, G A; McHenry, L; Watkins, J; Ginsberg, G G

2006-07-01

A new duodenoscope (the V-scope), with a modified elevator used in combination with a dedicated short guide wire, constitutes the V-system. This system is intended to allow fixation of the guide wire at the elevator lever, thereby enhancing the speed and reliability of accessory exchange over a guide wire during ERCP. The aim of this study was to evaluate the extent to which the V-system provides improved efficiency in comparison with conventional duodenoscope and guide wire combinations. This was an industry-sponsored multicenter randomized trial. Patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) procedures in which treatment was anticipated were randomly assigned to the V-system or to a conventional duodenoscope and accessories used routinely in each center. The parameters recorded included the total case time, fluoroscopy time, catheter/guide wire exchange time, guide wire repositioning, loss of guide wire access, and success or failure of guide wire fixation when using the V-system. Fifty patients were included, 22 in the conventional group and 28 in the V-system group. A total of 135 exchanges were carried out. The patients had up to six exchanges. The median exchange time was 19.4 s with the V-system and 31.7 s with the conventional systems ( P < 0.001). Guide wire repositioning was required less often in the V-system group ( P = 0.0005). The V-system effectively locked the guide wire in 63 of 71 exchanges (89 %). Loss of guide wire access occurred in two patients in the conventional group and four in the V-system group, attributable to failure to lock the guide wire early during the experience (no significant differences). The V-system can effectively secure the guide wire during accessory exchange in ERCP and reduces the time required to exchange accessories. This may enhance overall efficiency during ERCP.

30 CFR 75.705-11 - Use of grounded messenger wires; ungrounded systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Use of grounded messenger wires; ungrounded....705-11 Use of grounded messenger wires; ungrounded systems. Solely for purposes of grounding ungrounded high-voltage power systems, grounded messenger wires used to suspend the cables of such systems...

30 CFR 75.705-11 - Use of grounded messenger wires; ungrounded systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Use of grounded messenger wires; ungrounded....705-11 Use of grounded messenger wires; ungrounded systems. Solely for purposes of grounding ungrounded high-voltage power systems, grounded messenger wires used to suspend the cables of such systems...

49 CFR 393.28 - Wiring systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Wiring systems. 393.28 Section 393.28 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.28 Wiring systems...

49 CFR 393.28 - Wiring systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Wiring systems. 393.28 Section 393.28 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.28 Wiring systems...

49 CFR 393.28 - Wiring systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Wiring systems. 393.28 Section 393.28 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.28 Wiring systems...

49 CFR 393.28 - Wiring systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Wiring systems. 393.28 Section 393.28 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.28 Wiring systems...

30 CFR 77.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2010 CFR

2010-07-01

... pilot check wires. 77.902-2 Section 77.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Approved ground check systems not employing pilot check wires. Ground check systems not employing pilot check wires shall be approved by the Secretary only after it has been determined that the system...

30 CFR 77.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2011 CFR

2011-07-01

... pilot check wires. 77.902-2 Section 77.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Approved ground check systems not employing pilot check wires. Ground check systems not employing pilot check wires shall be approved by the Secretary only after it has been determined that the system...

30 CFR 77.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2012 CFR

2012-07-01

... pilot check wires. 77.902-2 Section 77.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Approved ground check systems not employing pilot check wires. Ground check systems not employing pilot check wires shall be approved by the Secretary only after it has been determined that the system...

30 CFR 77.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2013 CFR

2013-07-01

... pilot check wires. 77.902-2 Section 77.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Approved ground check systems not employing pilot check wires. Ground check systems not employing pilot check wires shall be approved by the Secretary only after it has been determined that the system...

30 CFR 77.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2014 CFR

2014-07-01

... pilot check wires. 77.902-2 Section 77.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Approved ground check systems not employing pilot check wires. Ground check systems not employing pilot check wires shall be approved by the Secretary only after it has been determined that the system...

The optimum spanning catenary cable

NASA Astrophysics Data System (ADS)

Wang, C. Y.

2015-03-01

A heavy cable spans two points in space. There exists an optimum cable length such that the maximum tension is minimized. If the two end points are at the same level, the optimum length is 1.258 times the distance between the ends. The optimum lengths for end points of different heights are also found.

46 CFR 129.340 - Cable and wiring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... buildup of condensation. (b) Each cable and wire must— (1) Have stranded copper conductors with sufficient... Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than cables, are used in systems operating at a potential of greater than 50 volts, the wire and associated...

46 CFR 129.340 - Cable and wiring.

Code of Federal Regulations, 2013 CFR

2013-10-01

... buildup of condensation. (b) Each cable and wire must— (1) Have stranded copper conductors with sufficient... Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than cables, are used in systems operating at a potential of greater than 50 volts, the wire and associated...

46 CFR 129.340 - Cable and wiring.

Code of Federal Regulations, 2014 CFR

2014-10-01

... buildup of condensation. (b) Each cable and wire must— (1) Have stranded copper conductors with sufficient... Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than cables, are used in systems operating at a potential of greater than 50 volts, the wire and associated...

46 CFR 129.340 - Cable and wiring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... buildup of condensation. (b) Each cable and wire must— (1) Have stranded copper conductors with sufficient... Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than cables, are used in systems operating at a potential of greater than 50 volts, the wire and associated...

A Vibrating Wire System For Quadrupole Fiducialization

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

Wolf, Zachary

2010-12-13

A vibrating wire system is being developed to fiducialize the quadrupoles between undulator segments in the LCLS. This note provides a detailed analysis of the system. The LCLS will have quadrupoles between the undulator segments to keep the electron beam focused. If the quadrupoles are not centered on the beam axis, the beam will receive transverse kicks, causing it to deviate from the undulator axis. Beam based alignment will be used to move the quadrupoles onto a straight line, but an initial, conventional alignment must place the quadrupole centers on a straight line to 100 {micro}m. In the fiducialization stepmore » of the initial alignment, the position of the center of the quadrupole is measured relative to tooling balls on the outside of the quadrupole. The alignment crews then use the tooling balls to place the magnet in the tunnel. The required error on the location of the quadrupole center relative to the tooling balls must be less than 25 {micro}m. In this note, we analyze a system under construction for the quadrupole fiducialization. The system uses the vibrating wire technique to position a wire onto the quadrupole magnetic axis. The wire position is then related to tooling balls using wire position detectors. The tooling balls on the wire position detectors are finally related to tooling balls on the quadrupole to perform the fiducialization. The total 25 {micro}m fiducialization error must be divided between these three steps. The wire must be positioned onto the quadrupole magnetic axis to within 10 {micro}m, the wire position must be measured relative to tooling balls on the wire position detectors to within 15 {micro}m, and tooling balls on the wire position detectors must be related to tooling balls on the quadrupole to within 10 {micro}m. The techniques used in these three steps will be discussed. The note begins by discussing various quadrupole fiducialization techniques used in the past and discusses why the vibrating wire technique is our method of choice. We then give an overview of the measurement system showing how the vibrating wire is positioned onto the quadrupole axis, how the wire position detectors locate the wire relative to tooling balls without touching the wire, and how the tooling ball positions are all measured. The novel feature of this system is the vibrating wire which we discuss in depth. We analyze the wire dynamics and calculate the expected sensitivity of the system. The note should be an aid in debugging the system by providing calculations to compare measurements to.« less

30 CFR 77.704-11 - Use of grounded messenger wires; ungrounded systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Use of grounded messenger wires; ungrounded... AREAS OF UNDERGROUND COAL MINES Grounding § 77.704-11 Use of grounded messenger wires; ungrounded systems. Solely for purposes of grounding ungrounded high-voltage power systems, grounded messenger wires...

30 CFR 77.704-11 - Use of grounded messenger wires; ungrounded systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Use of grounded messenger wires; ungrounded... AREAS OF UNDERGROUND COAL MINES Grounding § 77.704-11 Use of grounded messenger wires; ungrounded systems. Solely for purposes of grounding ungrounded high-voltage power systems, grounded messenger wires...

NASA wiring for space applications program test results

NASA Astrophysics Data System (ADS)

Stavnes, Mark; Hammoud, Ahmad

1995-11-01

The electrical power wiring tests results from the NASA Wiring for Space Applications program are presented. The goal of the program was to develop a base for the building of a lightweight, arc track-resistant electrical wiring system for aerospace applications. This new wiring system would be applied to such structures as pressurized modules, trans-atmospheric vehicles, LEO/GEO environments, and lunar and Martian environments. Technological developments from this program include the fabrication of new insulating materials, the production of new wiring constructions, an improved system design, and an advanced circuit protection design.

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.

Dynamic analysis of the deployment for mesh reflector deployable antennas with the cable-net structure

NASA Astrophysics Data System (ADS)

Zhang, Yiqun; Li, Na; Yang, Guigeng; Ru, Wenrui

2017-02-01

This paper presents a dynamic analysis approach for the composite structure of a deployable truss and cable-net system. An Elastic Catenary Element is adopted to model the slack/tensioned cables. Then, from the energy standpoint, the kinetic energy, elasticity-potential energy and geopotential energy of the cable-net structure and deployable truss are derived. Thus, the flexible multi-body dynamic model of the deployable antenna is built based on the Lagrange equation. The effect of the cable-net tension on the antenna truss is discussed and compared with previous publications and a dynamic deployment analysis is performed. Both the simulation and experimental results verify the validity of the method presented.

30 CFR 77.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2011 CFR

2011-07-01

... wires; approval by the Secretary. 77.803-2 Section 77.803-2 Mineral Resources MINE SAFETY AND HEALTH... check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires shall be approved by the Secretary only if it is determined that the system...

30 CFR 77.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2010 CFR

2010-07-01

... wires; approval by the Secretary. 77.803-2 Section 77.803-2 Mineral Resources MINE SAFETY AND HEALTH... check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires shall be approved by the Secretary only if it is determined that the system...

30 CFR 77.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2013 CFR

2013-07-01

... wires; approval by the Secretary. 77.803-2 Section 77.803-2 Mineral Resources MINE SAFETY AND HEALTH... check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires shall be approved by the Secretary only if it is determined that the system...

30 CFR 77.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2014 CFR

2014-07-01

... wires; approval by the Secretary. 77.803-2 Section 77.803-2 Mineral Resources MINE SAFETY AND HEALTH... check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires shall be approved by the Secretary only if it is determined that the system...

30 CFR 77.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2012 CFR

2012-07-01

... wires; approval by the Secretary. 77.803-2 Section 77.803-2 Mineral Resources MINE SAFETY AND HEALTH... check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires shall be approved by the Secretary only if it is determined that the system...

An Obstacle Alerting System for Agricultural Application

NASA Technical Reports Server (NTRS)

DeMaio, Joe

2003-01-01

Wire strikes are a significant cause of helicopter accidents. The aircraft most at risk are aerial applicators. The present study examines the effectiveness of a wire alert delivered by way of the lightbar, a GPS-based guidance system for aerial application. The alert lead-time needed to avoid an invisible wire is compared with that to avoid a visible wire. A flight simulator was configured to simulate an agricultural application helicopter. Two pilots flew simulated spray runs in fields with visible wires, invisible wires, and no wires. The wire alert was effective in reducing wire strikes. A lead-time of 3.5 sec was required for the alert to be effective. The lead- time required was the same whether the pilot could see the wire or not.

49 CFR 236.71 - Signal wires on pole line and aerial cable.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Signal wires on pole line and aerial cable. 236.71..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.71 Signal wires on pole line and aerial cable. Signal wire on...

49 CFR 236.71 - Signal wires on pole line and aerial cable.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Signal wires on pole line and aerial cable. 236.71..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.71 Signal wires on pole line and aerial cable. Signal wire on...

49 CFR 236.71 - Signal wires on pole line and aerial cable.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Signal wires on pole line and aerial cable. 236.71..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.71 Signal wires on pole line and aerial cable. Signal wire on...

75 FR 26743 - Pacific Gas and Electric Company; Notice of Environmental Site Review and Technical Meetings To...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-12

... Ocean, 2.5 to 3.0 nautical miles west of Manila on Samoa Peninsula of Humboldt Bay, near Eureka... Conversion devises (WEC), including multi-point catenary moorings and anchors; (2) marker buoys, navigation... interconnection to the electrical grid; and (6) appurtenant facilities. WEC types that may be installed may...

49 CFR 214.336 - On-track safety procedures for certain roadway work groups and adjacent tracks.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) A hi-rail vehicle (other than a catenary maintenance tower vehicle) being used for inspection or minor correction purposes, provided that such hi-rail vehicle is not coupled to one or more railroad cars. In accordance with § 214.315(a), where multiple hi-rail vehicles being used for inspection or...

49 CFR 214.336 - On-track safety procedures for certain roadway work groups and adjacent tracks.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) A hi-rail vehicle (other than a catenary maintenance tower vehicle) being used for inspection or minor correction purposes, provided that such hi-rail vehicle is not coupled to one or more railroad cars. In accordance with § 214.315(a), where multiple hi-rail vehicles being used for inspection or...

30 CFR 75.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Approved ground check systems not employing pilot check wires. 75.902-2 Section 75.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... employing pilot check wires. Ground check systems not employing pilot check wires will be approved only if...

30 CFR 75.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved ground check systems not employing pilot check wires. 75.902-2 Section 75.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... employing pilot check wires. Ground check systems not employing pilot check wires will be approved only if...

Pre-wired systems prove their worth.

PubMed

2012-03-01

The 'new generation' of modular wiring systems from Apex Wiring Solutions have been specified for two of the world's foremost teaching hospitals - the Royal London and St Bartholomew's Hospital, as part of a pounds sterling 1 billion redevelopment project, to cut electrical installation times, reduce on-site waste, and provide a pre-wired, factory-tested, power and lighting system. HEJ reports.

SpaceWire Data Handling Demonstration System

NASA Astrophysics Data System (ADS)

Mills, S.; Parkes, S. M.; O'Gribin, N.

2007-08-01

The SpaceWire standard was published in 2003 with the aim of providing a standard for onboard communications, defining the physical and data link layers of an interconnection, in order to improve reusability, reliability and to reduce the cost of mission development. The many benefits which it provides mean that it has already been used in a number of missions, both in Europe and throughout the world. Recent work by the SpaceWire community has included the development of higher level protocols for SpaceWire, such as the Remote Memory Access Protocol (RMAP) which can be used for many purposes, including the configuration of SpaceWire devices. Although SpaceWire has become very popular, the various ways in which it can be used are still being discovered, as are the most efficient ways to use it. At the same time, some in the space industry are not even aware of SpaceWire's existence. This paper describes the SpaceWire Data Handling Demonstration System that has been developed by the University of Dundee. This system simulates an onboard data handling network based on SpaceWire. It uses RMAP for all communication, and so demonstrates how SpaceWire and standardised higher level protocols can be used onboard a spacecraft. The system is not only a good advert for those who are unfamiliar with the benefits of SpaceWire, it is also a useful tool for those using SpaceWire to test ideas.

Adjustable Bracket For Entry Of Welding Wire

NASA Technical Reports Server (NTRS)

Gilbert, Jeffrey L.; Gutow, David A.

1993-01-01

Wire-entry bracket on welding torch in robotic welding system provides for adjustment of angle of entry of welding wire over range of plus or minus 30 degrees from nominal entry angle. Wire positioned so it does not hide weld joint in view of through-the-torch computer-vision system part of robot-controlling and -monitoring system. Swiveling bracket also used on nonvision torch on which wire-feed-through tube interferes with workpiece. Angle simply changed to one giving sufficient clearance.

30 CFR 75.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2014 CFR

2014-07-01

... pilot check wires. 75.902-2 Section 75.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... employing pilot check wires. Ground check systems not employing pilot check wires will be approved only if... ground continuity is broken. ...

30 CFR 75.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2012 CFR

2012-07-01

... pilot check wires. 75.902-2 Section 75.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... employing pilot check wires. Ground check systems not employing pilot check wires will be approved only if... ground continuity is broken. ...

30 CFR 75.902-2 - Approved ground check systems not employing pilot check wires.

Code of Federal Regulations, 2013 CFR

2013-07-01

... pilot check wires. 75.902-2 Section 75.902-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... employing pilot check wires. Ground check systems not employing pilot check wires will be approved only if... ground continuity is broken. ...

30 CFR 75.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2011 CFR

2011-07-01

... wires; approval by the Secretary. 75.803-2 Section 75.803-2 Mineral Resources MINE SAFETY AND HEALTH... Underground High-Voltage Distribution § 75.803-2 Ground check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires will be approved only if it...

30 CFR 75.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2010 CFR

2010-07-01

... wires; approval by the Secretary. 75.803-2 Section 75.803-2 Mineral Resources MINE SAFETY AND HEALTH... Underground High-Voltage Distribution § 75.803-2 Ground check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires will be approved only if it...

30 CFR 75.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2012 CFR

2012-07-01

... wires; approval by the Secretary. 75.803-2 Section 75.803-2 Mineral Resources MINE SAFETY AND HEALTH... Underground High-Voltage Distribution § 75.803-2 Ground check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires will be approved only if it...

30 CFR 75.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2013 CFR

2013-07-01

... wires; approval by the Secretary. 75.803-2 Section 75.803-2 Mineral Resources MINE SAFETY AND HEALTH... Underground High-Voltage Distribution § 75.803-2 Ground check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires will be approved only if it...

30 CFR 75.803-2 - Ground check systems not employing pilot check wires; approval by the Secretary.

Code of Federal Regulations, 2014 CFR

2014-07-01

... wires; approval by the Secretary. 75.803-2 Section 75.803-2 Mineral Resources MINE SAFETY AND HEALTH... Underground High-Voltage Distribution § 75.803-2 Ground check systems not employing pilot check wires; approval by the Secretary. Ground check systems not employing pilot check wires will be approved only if it...

Influence of bracket-slot design on the forces released by superelastic nickel-titanium alignment wires in different deflection configurations.

PubMed

Nucera, Riccardo; Gatto, Elda; Borsellino, Chiara; Aceto, Pasquale; Fabiano, Francesca; Matarese, Giovanni; Perillo, Letizia; Cordasco, Giancarlo

2014-05-01

To evaluate how different bracket-slot design characteristics affect the forces released by superelastic nickel-titanium (NiTi) alignment wires at different amounts of wire deflection. A three-bracket bending and a classic-three point bending testing apparatus were used to investigate the load-deflection properties of one superelastic 0.014-inch NiTi alignment wire in different experimental conditions. The selected NiTi archwire was tested in association with three bracket systems: (1) conventional twin brackets with a 0.018-inch slot, (2) a self-ligating bracket with a 0.018-inch slot, and (3) a self-ligating bracket with a 0.022-inch slot. Wire specimens were deflected at 2 mm and 4 mm. Use of a 0.018-inch slot bracket system, in comparison with use of a 0.022-inch system, increases the force exerted by the superelastic NiTi wires at a 2-mm deflection. Use of a self-ligating bracket system increases the force released by NiTi wires in comparison with the conventional ligated bracket system. NiTi wires deflected to a different maximum deflection (2 mm and 4 mm) release different forces at the same unloading data point (1.5 mm). Bracket design, type of experimental test, and amount of wire deflection significantly affected the amount of forces released by superelastic NiTi wires (P<.05). This phenomenon offers clinicians the possibility to manipulate the wire's load during alignment.

Basic EMC (Electromagnetic compatibility) technology advancement for C3 systems. Volume 4D: Modeling crosstalk in balanced twisted pairs

NASA Astrophysics Data System (ADS)

Koopman, D. A.; Paul, C. R.

1984-08-01

Electrical devices (computers, radar systems, communication radios, etc.) are interconnected by wires on most present systems. Electromagnetic fields produced by the excitation of these wires will cause unintentional coupling of signals onto nearby wires. This undesired electromagnetic coupling is termed crosstalk. It is important to be able to determine whether these crosstalk signals will cause the devices at the ends of the wires to malfunction. Wires are often grouped together in cable bundles or harnesses. The close proximity of wires in these bundles enhances the possibility that the crosstalk levels will be sufficiently large to cause malfunctions. The ability to predict crosstalk levels and the means to control crosstalk when it causes a problem are important to optimum system design. It interference of this type is allowed to surface during final system tests, a costly and time consuming retrofit of the wiring or the addition of filters and other interference control measures may be required.

Design and implementation of wire tension measurement system for MWPCs used in the STAR iTPC upgrade

DOE PAGES

Wang, Xu; Shen, Fuwang; Wang, Shuai; ...

2017-04-06

The STAR experiment at RHIC is planning to upgrade the Time Projection Chamber which lies at the heart of the detector. We have designed an instrument to measure the tension of the wires in the multi-wire proportional chambers (MWPCs) which will be used in the TPC upgrade. The wire tension measurement system causes the wires to vibrate and then it measures the fundamental frequency of the oscillation via a laser based optical platform. The platform can scan the entire wire plane, automatically, in a single run and obtain the wire tension on each wire with high precision. In this paper,more » the details about the measurement method and the system setup will be described. In addition, the test results for a prototype MWPC to be used in the STAR-iTPC upgrade will be presented.« less

Design and implementation of wire tension measurement system for MWPCs used in the STAR iTPC upgrade

NASA Astrophysics Data System (ADS)

Wang, Xu; Shen, Fuwang; Wang, Shuai; Feng, Cunfeng; Li, Changyu; Lu, Peng; Thomas, Jim; Xu, Qinghua; Zhu, Chengguang

2017-07-01

The STAR experiment at RHIC is planning to upgrade the Time Projection Chamber which lies at the heart of the detector. We have designed an instrument to measure the tension of the wires in the multi-wire proportional chambers (MWPCs) which will be used in the TPC upgrade. The wire tension measurement system causes the wires to vibrate and then it measures the fundamental frequency of the oscillation via a laser based optical platform. The platform can scan the entire wire plane, automatically, in a single run and obtain the wire tension on each wire with high precision. In this paper, the details about the measurement method and the system setup will be described. In addition, the test results for a prototype MWPC to be used in the STAR-iTPC upgrade will be presented.

Interchip link system using an optical wiring method.

PubMed

Cho, In-Kui; Ryu, Jin-Hwa; Jeong, Myung-Yung

2008-08-15

A chip-scale optical link system is presented with a transmitter/receiver and optical wire link. The interchip link system consists of a metal optical bench, a printed circuit board module, a driver/receiver integrated circuit, a vertical cavity surface-emitting laser/photodiode array, and an optical wire link composed of plastic optical fibers (POFs). We have developed a downsized POF and an optical wiring method that allows on-site installation with a simple annealing as optical wiring technologies for achieving high-density optical interchip interconnection within such devices. Successful data transfer measurements are presented.

Permeability, transport, and metabolism of solutes in Caco-2 cell monolayers: a theoretical study.

PubMed

Sun, Huadong; Pang, K Sandy

2008-01-01

We explored the properties of a catenary model that includes the basolateral (B), apical (A), and cellular compartments via simulations under linear and nonlinear conditions to understand the asymmetric observations arising from transporters, enzymes, and permeability in Caco-2 cells. The efflux ratio (EfR; P(app,B-->A)/P(app,A-->B)), obtained from the effective permeability from the A-->B and B-->A direction under linear conditions, was unity for passively permeable drugs whose transport does not involve transporters; the value was unaffected by cellular binding or metabolism, but increased with apical efflux. Metabolism was asymmetric, showing lesser metabolite accrual for the B-->A than A-->B direction because of inherent differences in the volumes for A and B. Moreover, the net flux (total - passive permeation) due to saturable apical efflux, absorption, or metabolism showed nonconformity to simple Michaelis-Menten kinetics against C(D,0), the loading donor concentration. EfR values differed with saturable apical efflux and metabolism (>1), as well as apical absorption (EfRs <1), but approached unity with high passive diffusive clearance (CL(d)) and increasing C(D,0) at a higher degree of saturation of the process. The J(max) (apparent V(max) estimated for the carrier system) and K(m)(') [or the K(m)('') based on a modified equation with the Hill coefficient (beta)] estimates from the Eadie-Hofstee plot revealed spurious correlations with the assigned V(max) and K(m). The sampling time, CL(d), and parameter space of K(m) and V(max) strongly influenced both the correlation and accuracy of estimates. Improved correlation was found for compounds with high CL(d). These observations showed that the catenary model is appropriate in the description of transport and metabolic data in Caco-2 cells.

A One Chip Hardened Solution for High Speed SpaceWire System Implementations. Session: Components

NASA Technical Reports Server (NTRS)

Marshall, Joseph R.; Berger, Richard W.; Rakow, Glenn P.

2007-01-01

An Application Specific Integrated Circuit (ASIC) that implements the SpaceWire protocol has been developed in a radiation hardened 0.25 micron CMOS technology. This effort began in March 2003 as a joint development between the NASA Goddard Space Flight Center (GSFC) and BAE Systems. The BAE Systems SpaceWire ASIC is comprised entirely of reusable core elements, many of which are already flight-proven. It incorporates a router with 4 SpaceWire ports and two local ports, dual PC1 bus interfaces, a microcontroller, 32KB of internal memory, and a memory controller for additional external memory use. The SpaceWire cores are also reused in other ASICs under development. The SpaceWire ASIC is planned for use on the Geostationary Operational Environmental Satellites (GOES)-R, the Lunar Reconnaissance Orbiter (LRO) and other missions. Engineering and flight parts have been delivered to programs and users. This paper reviews the SpaceWire protocol and those elements of it that have been built into the current and next SpaceWire reusable cores and features within the core that go beyond the current standard and can be enabled or disabled by the user. The adaptation of SpaceWire to BAE Systems' On Chip Bus (OCB) for compatibility with the other reusable cores will be reviewed and highlighted. Optional configurations within user systems and test boards will be shown. The physical implementation of the design will be described and test results from the hardware will be discussed. Application of this ASIC and other ASICs containing the SpaceWire cores and embedded microcontroller to Plug and Play and reconfigurable implementations will be described. Finally, the BAE Systems roadmap for SpaceWire developments will be updated, including some products already in design as well as longer term plans.

49 CFR 214.336 - On-track safety procedures for certain roadway work groups and adjacent tracks.

Code of Federal Regulations, 2014 CFR

2014-10-01

... or more of the following types of equipment: (i) A hi-rail vehicle or other rail-bound vehicle (other than a catenary maintenance tower vehicle) being used for inspection or minor correction purposes, provided that such vehicle is not coupled to one or more railroad cars. In accordance with § 214.315(a...

Some Mathematics and Physics in the Garden

ERIC Educational Resources Information Center

De Luca, R.

2012-01-01

Observing the way a watering hose is wrapped on a rotating cylinder, a catenary shape is detected for the suspended portion of the hose. We calculate the angle [alpha] the tangent to the curve at the highest point of the suspended portion makes with the horizontal. By means of this quantity, the length of the suspended and dragged portions of the…

Application of Template Matching for Improving Classification of Urban Railroad Point Clouds

PubMed Central

Arastounia, Mostafa; Oude Elberink, Sander

2016-01-01

This study develops an integrated data-driven and model-driven approach (template matching) that clusters the urban railroad point clouds into three classes of rail track, contact cable, and catenary cable. The employed dataset covers 630 m of the Dutch urban railroad corridors in which there are four rail tracks, two contact cables, and two catenary cables. The dataset includes only geometrical information (three dimensional (3D) coordinates of the points) with no intensity data and no RGB data. The obtained results indicate that all objects of interest are successfully classified at the object level with no false positives and no false negatives. The results also show that an average 97.3% precision and an average 97.7% accuracy at the point cloud level are achieved. The high precision and high accuracy of the rail track classification (both greater than 96%) at the point cloud level stems from the great impact of the employed template matching method on excluding the false positives. The cables also achieve quite high average precision (96.8%) and accuracy (98.4%) due to their high sampling and isolated position in the railroad corridor. PMID:27973452

A comparative study of wireless and wired sensors networks for deficit irrigation management

NASA Astrophysics Data System (ADS)

Torres Sánchez, Roque; Domingo Miguel, Rafael; Valles, Fulgencio Soto; Perez-Pastor, Alejandro; Lopez Riquelme, Juan Antonio; Blanco Montoya, Victor

2016-04-01

In recent years, the including of sensors in the context of agricultural water management, has received an increasing interest for the establishment of irrigation strategies, such as regulated deficit irrigation (RDI). These strategies allow a significant improvement of crop water productivity (marketable yield / water applied), especially in woody orchards. The application of these deficit irrigation strategies, requires the monitoring of variables related to the orchard, with the purpose of achieving an efficiently irrigation management, since it is necessary to know the soil and plant water status to achieve the level of water deficit desired in each phenological stage. These parameters involve the measurements of soil and plant parameters, by using appropriate instrumentation devices. Traditional centralized instrumentation systems include soil matric potential, water content and LVDT sensors which information is stored by dataloggers with a wired connection to the sensors. Nowadays, these wired systems are being replaced by wireless ones due, mainly, to cost savings in wiring and labor. These technologies (WSNs) allow monitoring a wide variety of parameters in orchards with high density of sensors using discrete and autonomous nodes in the trees or soil places where it is necessary, without using wires. In this paper we present a trial in a cherry crop orchard, with different irrigation strategies where both a wireless and a wired system have been deployed with the aim of obtaining the best criteria on how to select the most suitable technology in future agronomic monitoring systems. The first stage of this study includes the deploying of nodes, wires, dataloggers and the installation of the sensors (same for both, wired and wireless systems). This stage was done during the first 15 weeks of the trial. Specifically, 40 MPS6 soil matric potential, 20 Enviroscan water content and 40 (LVDT and band) dendometers were installed in order to cover the experimental irrigation trials: Control, Severe deficit, Moderate Deficit, Low Deficit and Traditional irrigation, with 4 repetitions (2 wired and 2 wireless) each one. The main goals were: (i) the ability of WSN for monitoring areas with high density of information, (ii) advantages and disadvantages compared to traditional wired instrumentation, (iii) energy sizing for autonomous operation of WSNs, (iv), strategies for deploying nodes to ensure the robustness of WSN. The main conclusions were: i) The WSNs need less time to be installed than the wired systems, ii) the WSNs is easier to install than the wired one because of the absence of wired links, iii) the advantage of WSNs is increased with high density of measure points, iv) the maintenance is higher in WSNs than the wired centralized systems, v) the acquisition costs is similar in both systems, vi) the installation costs is higher in Wired systems than WSNs, vii) the quality of data is similar in both systems although the data in WSNs are sooner available than wired, viii) the data robustness are higher in wired systems than WSN because of solar panel and battery lacks of WSN nodes. This work has been funded by the Ministerio de Economia y Competitividad AGL2013-49047-C2-1R.

A New Flying Wire System for the Tevatron

NASA Astrophysics Data System (ADS)

Blokland, Willem; Dey, Joseph; Vogel, Greg

1997-05-01

A new Flying Wires system replaces the old system to enhance the analysis of the beam emittance, improve the reliability, and handle the upcoming upgrades of the Tevatron. New VME data acquisition modules and timing modules allow for more bunches to be sampled more precisely. The programming language LabVIEW, running on a Macintosh computer, controls the VME modules and the nuLogic motion board that flies the wires. LabVIEW also analyzes and stores the data, and handles local and remote commands. The new system flies three wires and fits profiles of 72 bunches to a gaussian function within two seconds. A new console application operates the flying wires from any control console. This paper discusses the hardware and software setup, the capabilities and measurement results of the new Flying Wires system.

49 CFR 236.71 - Signal wires on pole line and aerial cable.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Signal wires on pole line and aerial cable. 236.71... Instructions: All Systems Wires and Cables § 236.71 Signal wires on pole line and aerial cable. Signal wire on... pole or other support. Signal wire shall not interfere with, or be interfered by, other wires on the...

49 CFR 236.71 - Signal wires on pole line and aerial cable.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Signal wires on pole line and aerial cable. 236.71... Instructions: All Systems Wires and Cables § 236.71 Signal wires on pole line and aerial cable. Signal wire on... pole or other support. Signal wire shall not interfere with, or be interfered by, other wires on the...

Beam Position and Phase Monitor - Wire Mapping System

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

Watkins, Heath A; Shurter, Robert B.; Gilpatrick, John D.

2012-04-10

The Los Alamos Neutron Science Center (LANSCE) deploys many cylindrical beam position and phase monitors (BPPM) throughout the linac to measure the beam central position, phase and bunched-beam current. Each monitor is calibrated and qualified prior to installation to insure it meets LANSCE requirements. The BPPM wire mapping system is used to map the BPPM electrode offset, sensitivity and higher order coefficients. This system uses a three-axis motion table to position the wire antenna structure within the cavity, simulating the beam excitation of a BPPM at a fundamental frequency of 201.25 MHz. RF signal strength is measured and recorded formore » the four electrodes as the antenna position is updated. An effort is underway to extend the systems service to the LANSCE facility by replacing obsolete electronic hardware and taking advantage of software enhancements. This paper describes the upgraded wire positioning system's new hardware and software capabilities including its revised antenna structure, motion control interface, RF measurement equipment and Labview software upgrades. The main purpose of the wire mapping system at LANSCE is to characterize the amplitude response versus beam central position of BPPMs before they are installed in the beam line. The wire mapping system is able to simulate a beam using a thin wire and measure the signal response as the wire position is varied within the BPPM aperture.« less

49 CFR 236.73 - Open-wire transmission line; clearance to other circuits.

Code of Federal Regulations, 2012 CFR

2012-10-01

... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.73 Open-wire transmission...

49 CFR 236.73 - Open-wire transmission line; clearance to other circuits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.73 Open-wire transmission...

49 CFR 236.74 - Protection of insulated wire; splice in underground wire.

Code of Federal Regulations, 2013 CFR

2013-10-01

... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.74 Protection of insulated...

49 CFR 236.74 - Protection of insulated wire; splice in underground wire.

Code of Federal Regulations, 2014 CFR

2014-10-01

... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.74 Protection of insulated...

49 CFR 236.74 - Protection of insulated wire; splice in underground wire.

Code of Federal Regulations, 2012 CFR

2012-10-01

... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.74 Protection of insulated...

49 CFR 236.73 - Open-wire transmission line; clearance to other circuits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.73 Open-wire transmission...

BAE Systems Radiation Hardened SpaceWire ASIC and Roadmap

NASA Technical Reports Server (NTRS)

Berger, Richard; Milliser, Myrna; Kapcio, Paul; Stanley, Dan; Moser, David; Koehler, Jennifer; Rakow, Glenn; Schnurr, Richard

2006-01-01

An Application Specific Integrated Circuit (ASIC) that implements the SpaceWire protocol has been developed in a radiation hardened 0.25 micron CMOS, technology. This effort began in March 2003 as a joint development between the NASA Goddard Space Flight Center (GSFC) and BAE Systems. The BAE Systems SpaceWire ASlC is comprised entirely of reusable core elements, many of which are already flight-proven. It incorporates a 4-port SpaceWire router with two local ports, dual PC1 bus interfaces, a microcontroller, 32KB of internal memory, -and a memory controller for additional external memory use. The SpaceWire ASlC is planned for use on both the Geostationary Operational Environmental Satellites (GOES)-R and the Lunar Reconnaissance Orbiter (LRO). Engineering parts have already been delivered to both programs. This paper discusses the SpaceWire protocol and those elements of it that have been built into the current SpaceWire reusable core. There are features within the core that go beyond the current standard that can be enabled or disabled by the user and these will be described. The adaptation of SpaceWire to BAE Systems' On Chip Bus (OCB) for compatibility with the other reusable cores will be discussed. Optional configurations within user systems will be shown. The physical imp!ementation of the design will be described and test results from the hardware will be discussed. Finally, the BAE Systems roadmap for SpaceWire developments will be discussed, including some products already in design as well as longer term plans.

Wire-bonder-assisted integration of non-bondable SMA wires into MEMS substrates

NASA Astrophysics Data System (ADS)

Fischer, A. C.; Gradin, H.; Schröder, S.; Braun, S.; Stemme, G.; van der Wijngaart, W.; Niklaus, F.

2012-05-01

This paper reports on a novel technique for the integration of NiTi shape memory alloy wires and other non-bondable wire materials into silicon-based microelectromechanical system structures using a standard wire-bonding tool. The efficient placement and alignment functions of the wire-bonding tool are used to mechanically attach the wire to deep-etched silicon anchoring and clamping structures. This approach enables a reliable and accurate integration of wire materials that cannot be wire bonded by traditional means.

Method and system for controlling chemical reactions between superconductors and metals in superconducting cables

DOEpatents

Shen, Tengming

2016-11-15

A method, system, and apparatus for fabricating a high-strength Superconducting cable comprises pre-oxidizing at least one high-strength alloy wire, coating at least one Superconducting wire with a protective layer, and winding the high-strength alloy wire and the Superconducting wire to form a high-strength Superconducting cable.

Method and system for controlling chemical reactions between superconductors and metals in superconducting cables

DOEpatents

Shen, Tengming

2018-01-02

A method, system, and apparatus for fabricating a high-strength Superconducting cable comprises pre-oxidizing at least one high-strength alloy wire, coating at least one Superconducting wire with a protective layer, and winding the high-strength alloy wire and the Superconducting wire to form a high-strength Superconducting cable.

System and method for evaluating a wire conductor

DOEpatents

Panozzo, Edward; Parish, Harold

2013-10-22

A method of evaluating an electrically conductive wire segment having an insulated intermediate portion and non-insulated ends includes passing the insulated portion of the wire segment through an electrically conductive brush. According to the method, an electrical potential is established on the brush by a power source. The method also includes determining a value of electrical current that is conducted through the wire segment by the brush when the potential is established on the brush. The method additionally includes comparing the value of electrical current conducted through the wire segment with a predetermined current value to thereby evaluate the wire segment. A system for evaluating an electrically conductive wire segment is also disclosed.

47 CFR 36.341 - Cable and wire facilities expenses-Account 6410 (Class B telephone companies); Accounts 6411...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Cable and wire facilities expenses-Account 6410... Operating Expenses and Taxes Cable and Wire Facilities Expenses § 36.341 Cable and wire facilities expenses... network cable, aerial wire, and conduit systems. (b) The general method of separating cable and wire...

47 CFR 36.341 - Cable and wire facilities expenses-Account 6410 (Class B telephone companies); Accounts 6411...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Cable and wire facilities expenses-Account 6410... Operating Expenses and Taxes Cable and Wire Facilities Expenses § 36.341 Cable and wire facilities expenses... network cable, aerial wire, and conduit systems. (b) The general method of separating cable and wire...

Traveling Along a Zipline

DTIC Science & Technology

2011-03-01

resultados se obtienen al equilibrar las fuerzas en las direcciones horizontal y vertical, de modo que el tratamiento es accesible para mayores de física...masa. A medida que aumenta el peso del ciclista de 0 a, las trayectorias de manera uniforme interpolar entre una catenaria y una elipse. Estos...an algebraic equation. Keywords: Zipline, curved spacetime, force balance, catenary. Resumen La trayectoria de un jinete lentamente atravesando

Modelling Soil-Landscapes in Coastal California Hills Using Fine Scale Terrestrial Lidar

NASA Astrophysics Data System (ADS)

Prentice, S.; Bookhagen, B.; Kyriakidis, P. C.; Chadwick, O.

2013-12-01

Digital elevation models (DEMs) are the dominant input to spatially explicit digital soil mapping (DSM) efforts due to their increasing availability and the tight coupling between topography and soil variability. Accurate characterization of this coupling is dependent on DEM spatial resolution and soil sampling density, both of which may limit analyses. For example, DEM resolution may be too coarse to accurately reflect scale-dependent soil properties yet downscaling introduces artifactual uncertainty unrelated to deterministic or stochastic soil processes. We tackle these limitations through a DSM effort that couples moderately high density soil sampling with a very fine scale terrestrial lidar dataset (20 cm) implemented in a semiarid rolling hillslope domain where terrain variables change rapidly but smoothly over short distances. Our guiding hypothesis is that in this diffusion-dominated landscape, soil thickness is readily predicted by continuous terrain attributes coupled with catenary hillslope segmentation. We choose soil thickness as our keystone dependent variable for its geomorphic and hydrologic significance, and its tendency to be a primary input to synthetic ecosystem models. In defining catenary hillslope position we adapt a logical rule-set approach that parses common terrain derivatives of curvature and specific catchment area into discrete landform elements (LE). Variograms and curvature-area plots are used to distill domain-scale terrain thresholds from short range order noise characteristic of very fine-scale spatial data. The revealed spatial thresholds are used to condition LE rule-set inputs, rendering a catenary LE map that leverages the robustness of fine-scale terrain data to create a generalized interpretation of soil geomorphic domains. Preliminary regressions show that continuous terrain variables alone (curvature, specific catchment area) only partially explain soil thickness, and only in a subset of soils. For example, at spatial scales up 20, curvature explains 40% of soil thickness variance among soils <3 m deep, while soils >3 m deep show no clear relation to curvature. To further demonstration our geomorphic segmentation approach, we apply it to DEM domains where diffusion processes are less dominant than in our primary study area. Classified landform map derived from fine scale terrestrial lidar. Color classes depict hydrogeomorphic process domains in zero order watersheds.

Magnetorheological fluid based automotive steer-by-wire systems

NASA Astrophysics Data System (ADS)

Ahmadkhanlou, Farzad; Washington, Gregory N.; Bechtel, Stephen E.; Wang, Yingru

2006-03-01

The idea of this paper is to design a Magnetorheological (MR) fluid based damper for steer-by-wire systems to provide sensory feedback to the driver. The advantages of using MR fluids in haptic devices stem from the increase in transparency gained from the lightweight semiactive system and controller implementation. The performance of MR fluid based steer-by wire system depends on MR fluid model and specifications, MR damper geometry, and the control algorithm. All of these factors are addressed in this study. The experimental results show the improvements in steer-by-wire by adding force feedback to the system.

14 CFR 121.1111 - Electrical wiring interconnection systems (EWIS) maintenance program.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Electrical wiring interconnection systems... Airworthiness and Safety Improvements § 121.1111 Electrical wiring interconnection systems (EWIS) maintenance program. (a) Except as provided in paragraph (f) of this section, this section applies to transport...

46 CFR 110.25-1 - Plans and information required for new construction.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-line wiring diagram of the power system, supported, by cable lists, panelboard summaries, and other... computed operating loads for each condition of operation. (c) Elementary and isometric or deck wiring plans...) Manual alarm system; and (11) Supervised patrol system. (d) Deck wiring or schematic plans of power...

A Simulation Study on Take-Off and Landing Dynamics of the Aircraft of a Fly-By-Wire Control System

DTIC Science & Technology

1993-01-07

L:V,"DIN G DYN;AMICS OF THE AIRCRAFT OF A FLY-BY-WIRE CONTROL SYSTEM by Y achang Feng, Gang Chert, Peiqiong Li 93-00985 Distribution unlimit ed. FASTC...FLY-BY-WIRE CONTROL SYSTEM By: Yachang Feng, Gang Chen, Peiqiong- Li English pages: 17 Source: Hangkon, Xuebao, Vol. 12, No. 6, June, 1991; pp. 252-258...Landing Dynamics of the Aircraft of a Fly-By-Wire Control System Beijing University of Aeronautics and Astronautics Yachang FENG, Gang CHEN and Peiqiong Li

International space station wire program

NASA Technical Reports Server (NTRS)

May, Todd

1995-01-01

Hardware provider wire systems and current wire insulation issues for the International Space Station (ISS) program are discussed in this viewgraph presentation. Wire insulation issues include silicone wire contamination, Tefzel cold temperature flexibility, and Russian polyimide wire insulation. ISS is a complex program with hardware developed and managed by many countries and hundreds of contractors. Most of the obvious wire insulation issues are known by contractors and have been precluded by proper selection.

NASA wiring for space applications program

NASA Technical Reports Server (NTRS)

Schulze, Norman

1995-01-01

An overview of the NASA Wiring for Space Applications Program and its relationship to NASA's space technology enterprise is given in viewgraph format. The mission of the space technology enterprise is to pioneer, with industry, the development and use of space technology to secure national economic competitiveness, promote industrial growth, and to support space missions. The objectives of the NASA Wiring for Space Applications Program is to improve the safety, performance, and reliability of wiring systems for space applications and to develop improved wiring technologies for NASA flight programs and commercial applications. Wiring system failures in space and commercial applications have shown the need for arc track resistant wiring constructions. A matrix of tests performed versus wiring constructions is presented. Preliminary data indicate the performance of the Tensolite and Filotex hybrid constructions are the best of the various candidates.

Acquisition of Turbulence Data Using the DST Group Constant-Temperature Hot-Wire Anemometer System

DTIC Science & Technology

2015-10-01

fluctuations in the low-speed wind tunnel at DST Group. The use of both single- wire and crossed- wire (2 wire ) probes is described. Areas covered include a...fluid-flow studies, including testing of models of aircraft, ships and submarines in wind and water tunnels. Hot- wire anemometers and associated hot...spectra of velocity fluctuations in the low-speed wind tunnel at DST Group. The use of both single- wire and crossed- wire (2 wires ) probes is

Operation and force analysis of the guide wire in a minimally invasive vascular interventional surgery robot system

NASA Astrophysics Data System (ADS)

Yang, Xue; Wang, Hongbo; Sun, Li; Yu, Hongnian

2015-03-01

To develop a robot system for minimally invasive surgery is significant, however the existing minimally invasive surgery robots are not applicable in practical operations, due to their limited functioning and weaker perception. A novel wire feeder is proposed for minimally invasive vascular interventional surgery. It is used for assisting surgeons in delivering a guide wire, balloon and stenting into a specific lesion location. By contrasting those existing wire feeders, the motion methods for delivering and rotating the guide wire in blood vessel are described, and their mechanical realization is presented. A new resistant force detecting method is given in details. The change of the resistance force can help the operator feel the block or embolism existing in front of the guide wire. The driving torque for rotating the guide wire is developed at different positions. Using the CT reconstruction image and extracted vessel paths, the path equation of the blood vessel is obtained. Combining the shapes of the guide wire outside the blood vessel, the whole bending equation of the guide wire is obtained. That is a risk criterion in the delivering process. This process can make operations safer and man-machine interaction more reliable. A novel surgery robot for feeding guide wire is designed, and a risk criterion for the system is given.

49 CFR 236.76 - Tagging of wires and interference of wires or tags with signal apparatus.

Code of Federal Regulations, 2012 CFR

2012-10-01

... INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.76 Tagging of...

49 CFR 236.76 - Tagging of wires and interference of wires or tags with signal apparatus.

Code of Federal Regulations, 2014 CFR

2014-10-01

... INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.76 Tagging of...

49 CFR 236.76 - Tagging of wires and interference of wires or tags with signal apparatus.

Code of Federal Regulations, 2013 CFR

2013-10-01

... INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.76 Tagging of...

Filter line wiring designs in aircraft

NASA Astrophysics Data System (ADS)

Rowe, Richard M.

1990-10-01

The paper presents a harness design using a filter-line wire technology and appropriate termination methods to help meet high-energy radiated electromagnetic field (HERF) requirements for protection against the adverse effects of EMI on electrical and avionic systems. Filter-line interconnect harnessing systems discussed consist of high-performance wires and cables; when properly wired they suppress conducted and radiated EMI above 100 MHz. Filter-line termination devices include backshell adapters, braid splicers, and shield terminators providing 360-degree low-impedance terminations and enhancing maintainability of the system.

Characteristics of coated copper wire specimens using high frequency ultrasonic complex vibration welding equipments.

PubMed

Tsujino, J; Ihara, S; Harada, Y; Kasahara, K; Sakamaki, N

2004-04-01

Welding characteristic of thin coated copper wires were studied using 40, 60, 100 kHz ultrasonic complex vibration welding equipments with elliptical to circular vibration locus. The complex vibration systems consisted of a longitudinal-torsional vibration converter and a driving longitudinal vibration system. Polyurethane coated copper wires of 0.036 mm outer diameter and copper plates of 0.3 mm thickness and the other dimension wires were used as welding specimens. The copper wire part is completely welded on the copper substrate and the insulated coating material is driven from welded area to outsides of the wire specimens by high frequency complex vibration.

49 CFR 236.74 - Protection of insulated wire; splice in underground wire.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Protection of insulated wire; splice in underground wire. 236.74 Section 236.74 Transportation Other Regulations Relating to Transportation (Continued..., AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.74 Protection of insulated...

49 CFR 236.74 - Protection of insulated wire; splice in underground wire.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Protection of insulated wire; splice in underground wire. 236.74 Section 236.74 Transportation Other Regulations Relating to Transportation (Continued..., AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.74 Protection of insulated...

49 CFR 236.76 - Tagging of wires and interference of wires or tags with signal apparatus.

Code of Federal Regulations, 2010 CFR

2010-10-01

... with signal apparatus. 236.76 Section 236.76 Transportation Other Regulations Relating to... wires and interference of wires or tags with signal apparatus. Each wire shall be tagged or otherwise so... apparatus. [49 FR 3384, Jan. 26, 1984] Inspections and Tests; All Systems ...

49 CFR 236.76 - Tagging of wires and interference of wires or tags with signal apparatus.

Code of Federal Regulations, 2011 CFR

2011-10-01

... with signal apparatus. 236.76 Section 236.76 Transportation Other Regulations Relating to... wires and interference of wires or tags with signal apparatus. Each wire shall be tagged or otherwise so... apparatus. [49 FR 3384, Jan. 26, 1984] Inspections and Tests; All Systems ...

Mapping the Galvanic Corrosion of Three Metals Coupled with a Wire Beam Electrode: The Influence of Temperature and Relative Geometrical Position.

PubMed

Ju, Hong; Yang, Yuan-Feng; Liu, Yun-Fei; Liu, Shu-Fa; Duan, Jin-Zhuo; Li, Yan

2018-02-28

The local electrochemical properties of galvanic corrosion for three coupled metals in a desalination plant were investigated with three wire-beam electrodes as wire sensors: aluminum brass (HAl77-2), titanium (TA2), and 316L stainless steel (316L SS). These electrodes were used with artificial seawater at different temperatures. The potential and current-density distributions of the three-metal coupled system are inhomogeneous. The HAl77-2 wire anodes were corroded in the three-metal coupled system. The TA2 wires acted as cathodes and were protected; the 316L SS wires acted as secondary cathodes. The temperature and electrode arrangement have important effects on the galvanic corrosion of the three-metal coupled system. The corrosion current of the HAl77-2 increased with temperature indicating enhanced anode corrosion at higher temperature. In addition, the corrosion of HAl77-2 was more significant when the HAl77-2 wires were located in the middle of the coupled system than with the other two metal arrangement styles.

Mapping the Galvanic Corrosion of Three Metals Coupled with a Wire Beam Electrode: The Influence of Temperature and Relative Geometrical Position

PubMed Central

Liu, Yun-Fei; Liu, Shu-Fa; Duan, Jin-Zhuo

2018-01-01

The local electrochemical properties of galvanic corrosion for three coupled metals in a desalination plant were investigated with three wire-beam electrodes as wire sensors: aluminum brass (HAl77-2), titanium (TA2), and 316L stainless steel (316L SS). These electrodes were used with artificial seawater at different temperatures. The potential and current–density distributions of the three-metal coupled system are inhomogeneous. The HAl77-2 wire anodes were corroded in the three-metal coupled system. The TA2 wires acted as cathodes and were protected; the 316L SS wires acted as secondary cathodes. The temperature and electrode arrangement have important effects on the galvanic corrosion of the three-metal coupled system. The corrosion current of the HAl77-2 increased with temperature indicating enhanced anode corrosion at higher temperature. In addition, the corrosion of HAl77-2 was more significant when the HAl77-2 wires were located in the middle of the coupled system than with the other two metal arrangement styles. PMID:29495617

75 FR 7557 - Airworthiness Directives; The Boeing Company Model 767 Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-22

... shorts in many systems, including the spar fuel shut off valve, oxygen mask deployment, and burned wires... and wire bundles, causing shorts in many systems, including the spar fuel shut off valve, oxygen mask... and wire bundles, causing shorts in many systems, including the spar fuel shut off valve, oxygen mask...

75 FR 68245 - Airworthiness Directives; McDonnell Douglas Corporation Model MD-90-30 Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-05

... shutoff system wiring. This proposed AD was prompted by a possible latent failure in the fire handle... engine fuel fire shutoff handle is activated. Separating the fire handle shutoff system wiring will... handle shutoff system wiring. FAA's Determination We are proposing this AD because we evaluated all the...

Operational environments for electrical power wiring on NASA space systems

NASA Technical Reports Server (NTRS)

Stavnes, Mark W.; Hammoud, Ahmad N.; Bercaw, Robert W.

1994-01-01

Electrical wiring systems are used extensively on NASA space systems for power management and distribution, control and command, and data transmission. The reliability of these systems when exposed to the harsh environments of space is very critical to mission success and crew safety. Failures have been reported both on the ground and in flight due to arc tracking in the wiring harnesses, made possible by insulation degradation. This report was written as part of a NASA Office of Safety and Mission Assurance (Code Q) program to identify and characterize wiring systems in terms of their potential use in aerospace vehicles. The goal of the program is to provide the information and guidance needed to develop and qualify reliable, safe, lightweight wiring systems, which are resistant to arc tracking and suitable for use in space power applications. This report identifies the environments in which NASA spacecraft will operate, and determines the specific NASA testing requirements. A summary of related test programs is also given in this report. This data will be valuable to spacecraft designers in determining the best wiring constructions for the various NASA applications.

The construction technique of the high granularity and high transparency drift chamber of MEG II

NASA Astrophysics Data System (ADS)

Chiarello, G.; Chiri, C.; Corvaglia, A.; Grancagnolo, F.; Miccoli, A.; Panareo, M.; Pinto, C.; Spedicato, M.; Tassielli, G. F.

2017-07-01

The MEG experiment searches for the charged lepton flavor violating decay, μ +→ e+γ. MEG has already determined the world best upper limit on the branching ratio BR<4.2× 10-13 at 90% CL. An upgrade of the whole detector has been approved to obtain a substantial increase in sensitivity. Currently MEG is in upgrade phases, this phase involves all the detectors. The new positron tracker is a single volume, full stereo, small cells drift chamber (DCH) co-axial to the beam line. It is composed of 10 concentric layers and each single drift cell is approximately square 7 mm side, with a 20 μ m gold plated W sense wire surrounded by 40 μ m and 50 μ m silver plated Al field wires in a ratio of 5:1, about 12,000 wires. Due to the high wire density (12 wires/cm2), the use of the classical feed-through technique as wire anchoring system could hardly be implemented and therefore it was necessary to develop new wiring strategies. The number of wires and the stringent requirements on the precision of their position and on the uniformity of the wire mechanical tension impose the use of an automatic system to operate the wiring procedures. This wiring robot, designed and built at the INFN Lecce and University of Salento laboratories, consists of: ṡ a semiautomatic wiring machine with a high precision on wire mechanical tensioning (better than 0.5 g) and on wire positioning (20 μ m) for simultaneous wiring of multiwire layers; ṡ a contact-less infrared laser soldering tool; ṡ an automatic handling system for storing and transporting the multi-wire layers. The drift chamber is currently under construction at INFN and should be completed by the end of summer 2017 to be then delivered to PSI for commissioning.

A wire scanner system for characterizing the BNL energy recovery LINAC beam position monitor system

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

Michnoff R.; Biscardi, C.; Cerniglia, P.

2012-04-15

A stepper motor controlled wire scanner system has recently been modified to support testing of the Brookhaven National Laboratory (BNL) Collider-Accelerator department's Energy Recovery Linac (ERL) beam position monitor (BPM) system. The ERL BPM consists of four 9.33 mm diameter buttons mounted at 90 degree spacing in a cube with 1.875 inch inside diameter. The buttons were designed by BNL and fabricated by Times Microwave Systems. Libera brilliance single pass BPM electronic modules with 700 MHz bandpass filter, manufactured by Instrumentation Technologies, will be used to measure the transverse beam positions at 14 locations around the ERL. The wire scannermore » assembly provides the ability to measure the BPM button response to a pulsed wire, and evaluate and calibrate the Libera position measurement electronics. A description of the wire scanner system and test result data will be presented.« less

In-Situ Wire Damage Detection System

NASA Technical Reports Server (NTRS)

Williams, Martha; Roberson, Luke; Tate, Lanetra; Smith, Trent; Gibson, Tracy; Medelius, Pedro; Jolley, Scott

2012-01-01

An In-Situ Wire Damage Detection System (ISWDDS) has been developed that is capable of detecting damage to a wire insulation, or a wire conductor, or to both. The system will allow for realtime, continuous monitoring of wiring health/integrity and reduce the number of false negatives and false positives while being smaller, lighter in weight, and more robust than current systems. The technology allows for improved safety and significant reduction in maintenance hours for aircraft, space vehicles, satellites, and other critical high-performance wiring systems for industries such as energy production and mining. The integrated ISWDDS is comprised of two main components: (1) a wire with an innermost core conductor, an inner insulation film, a conductive layer or inherently conductive polymer (ICP) covering the inner insulation film, an outermost insulation jacket; and (2) smart connectors and electronics capable of producing and detecting electronic signals, and a central processing unit (CPU) for data collection and analysis. The wire is constructed by applying the inner insulation films to the conductor, followed by the outer insulation jacket. The conductive layer or ICP is on the outer surface of the inner insulation film. One or more wires are connected to the CPU using the smart connectors, and up to 64 wires can be monitored in real-time. The ISWDDS uses time domain reflectometry for damage detection. A fast-risetime pulse is injected into either the core conductor or conductive layer and referenced against the other conductor, producing transmission line behavior. If either conductor is damaged, then the signal is reflected. By knowing the speed of propagation of the pulse, and the time it takes to reflect, one can calculate the distance to and location of the damage.

Monte Carlo simulation to analyze the cost-benefit of radioactive seed localization versus wire localization for breast-conserving surgery in fee-for-service health care systems compared with accountable care organizations.

PubMed

Loving, Vilert A; Edwards, David B; Roche, Kevin T; Steele, Joseph R; Sapareto, Stephen A; Byrum, Stephanie C; Schomer, Donald F

2014-06-01

In breast-conserving surgery for nonpalpable breast cancers, surgical reexcision rates are lower with radioactive seed localization (RSL) than wire localization. We evaluated the cost-benefit of switching from wire localization to RSL in two competing payment systems: a fee-for-service (FFS) system and a bundled payment system, which is typical for accountable care organizations. A Monte Carlo simulation was developed to compare the cost-benefit of RSL and wire localization. Equipment utilization, procedural workflows, and regulatory overhead differentiate the cost between RSL and wire localization. To define a distribution of possible cost scenarios, the simulation randomly varied cost drivers within fixed ranges determined by hospital data, published literature, and expert input. Each scenario was replicated 1000 times using the pseudorandom number generator within Microsoft Excel, and results were analyzed for convergence. In a bundled payment system, RSL reduced total health care cost per patient relative to wire localization by an average of $115, translating into increased facility margin. In an FFS system, RSL reduced total health care cost per patient relative to wire localization by an average of $595 but resulted in decreased facility margin because of fewer surgeries. In a bundled payment system, RSL results in a modest reduction of cost per patient over wire localization and slightly increased margin. A fee-for-service system suffers moderate loss of revenue per patient with RSL, largely due to lower reexcision rates. The fee-for-service system creates a significant financial disincentive for providers to use RSL, although it improves clinical outcomes and reduces total health care costs.

Electromagnetic interference in intraoperative monitoring of motor evoked potentials and a wireless solution.

PubMed

Farajidavar, Aydin; Seifert, Jennifer L; Delgado, Mauricio R; Sparagana, Steven; Romero-Ortega, Mario I; Chiao, J-C

2016-02-01

Intraoperative neurophysiological monitoring (IONM) is utilized to minimize neurological morbidity during spine surgery. Transcranial motor evoked potentials (TcMEPs) are principal IONM signals in which the motor cortex of the subject is stimulated with electrical pulses and the evoked potentials are recorded from the muscles of interest. Currently available monitoring systems require the connection of 40-60 lengthy lead wires to the patient. These wires contribute to a crowded and cluttered surgical environment, and limit the maneuverability of the surgical team. In this work, it was demonstrated that the cumbersome wired system is vulnerable to electromagnetic interference (EMI) produced by operating room (OR) equipment. It was hypothesized that eliminating the lengthy recording wires can remove the EMI induced in the IONM signals. Hence, a wireless system to acquire TcMEPs was developed and validated through bench-top and animal experiments. Side-by-side TcMEPs acquisition from the wired and wireless systems in animal experiments under controlled conditions (absence of EMI from OR equipment) showed comparable magnitudes and waveforms, thus demonstrating the fidelity in the signal acquisition of the wireless solution. The robustness of the wireless system to minimize EMI was compared with a wired-system under identical conditions. Unlike the wired-system, the wireless system was not influenced by the electromagnetic waves from the C-Arm X-ray machine and temperature management system in the OR. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

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

Wang, Xu; Shen, Fuwang; Wang, Shuai

The STAR experiment at RHIC is planning to upgrade the Time Projection Chamber which lies at the heart of the detector. We have designed an instrument to measure the tension of the wires in the multi-wire proportional chambers (MWPCs) which will be used in the TPC upgrade. The wire tension measurement system causes the wires to vibrate and then it measures the fundamental frequency of the oscillation via a laser based optical platform. The platform can scan the entire wire plane, automatically, in a single run and obtain the wire tension on each wire with high precision. In this paper,more » the details about the measurement method and the system setup will be described. In addition, the test results for a prototype MWPC to be used in the STAR-iTPC upgrade will be presented.« less

Characterization System of Multi-pixel Array TES Microcalorimeter

NASA Astrophysics Data System (ADS)

Yoshimoto, Shota; Maehata, Keisuke; Mitsuda, Kazuhisa; Yamanaka, Yoshihiro; Sakai, Kazuhiro; Nagayoshi, Kenichiro; Yamamoto, Ryo; Hayashi, Tasuku; Muramatsu, Haruka

We have constructed characterization system for 64-pixel array transition-edge sensor (TES) microcalorimeter using a 3He-4He dilution refrigerator (DR) with the cooling power of 60 µW at a temperature of 100 mK. A stick equipped with 384 of Manganin wires was inserted into the refrigerator to perform characteristic measurements of 64-pixel array TES microcalorimeter and superconducting quantum interference device (SQUID) array amplifiers. The stick and Manganin wires were thermally anchored at temperatures of 4 and 1 K with sufficient thermal contact. The cold end of the Manganin wires were thermally anchored and connected to CuNi clad NbTi wires at 0.7 K anchor. Then CuNi clad NbTi wires were wired to connectors placed on the holder mounted on the cold stage attached to the base plate of the mixing chamber. The heat flow to the cold stage through the installed wires was estimated to be 0.15 µW. In the operation test the characterization system maintained temperature below 100 mK.

49 CFR 236.57 - Shunt and fouling wires.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Shunt and fouling wires. 236.57 Section 236.57...: All Systems Track Circuits § 236.57 Shunt and fouling wires. (a) Except as provided in paragraph (b) of this section, shunt wires and fouling wires hereafter installed or replaced shall consist of at...

49 CFR 236.73 - Open-wire transmission line; clearance to other circuits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Open-wire transmission line; clearance to other..., AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.73 Open-wire transmission line; clearance to other circuits. Open-wire transmission line operating at voltage of 750 volts or...

49 CFR 236.73 - Open-wire transmission line; clearance to other circuits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Open-wire transmission line; clearance to other..., AND APPLIANCES Rules and Instructions: All Systems Wires and Cables § 236.73 Open-wire transmission line; clearance to other circuits. Open-wire transmission line operating at voltage of 750 volts or...

49 CFR 236.57 - Shunt and fouling wires.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Shunt and fouling wires. 236.57 Section 236.57...: All Systems Track Circuits § 236.57 Shunt and fouling wires. (a) Except as provided in paragraph (b) of this section, shunt wires and fouling wires hereafter installed or replaced shall consist of at...

47 CFR 68.213 - Installation of other than “fully protected” non-system simple customer premises wiring.

Code of Federal Regulations, 2010 CFR

2010-10-01

... only to “unprotected” premises wiring used with simple installations of wiring for up to four line residential and business telephone service. More complex installations of wiring for multiple line services... requirements, for installation and maintenance of wiring on the subscriber's side of the demarcation point...

View southeast of main supervisory board showing panels 3 through ...

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

View southeast of main supervisory board showing panels 3 through 11; panel 3 at far left contains meters for monitoring power in the system; panel 4 contains controls for controlling heaters to keep track twitches free of ice and snow; panels 5, 6, and 7 date to the 1935 installation and control the catenary in the area of the station yard. These work on 120 volts direct current; panel 8 contains circuit breakers (rupture switches) which control power to individual tracks in the station area; panels 9 and 10 house controls for the West Philadelphia sub-station; panel 11 controls sub-station 13 in South Wilmington Delaware and miscellaneous meters - Thirtieth Street Station, Power Director Center, Thirtieth & Market Streets in Amtrak Railroad Station, Philadelphia, Philadelphia County, PA

Crewmember repairing the Regenerative Carbon Dioxide Removal System wiring.

NASA Technical Reports Server (NTRS)

1992-01-01

Mission Pilot Ken Bowersox, busy at work on the wiring harness for the Regenerative Carbon Dioxide Removal System located under the mid deck floor. Photo shows Bowersox splicing wires together to 'fool' a faulty sensor that caused the 'air conditioner' to shut down.

Calibration, Data Acquisition, and Post Analysis of Turbulent Fluid Flow in a Calibration Jet Using Hot-wire Anemometry

NASA Technical Reports Server (NTRS)

Moreno, Michelle

2004-01-01

The Turbine Branch concentrates on the following areas: Computational Fluid Dynamics (CFD), and implementing experimental procedures to obtain physical modeling data. Hot-wire Anemometry is a valuable tool for obtaining physical modeling data. Hot-wire Anemometry is likely to remain the principal research tool for most turbulent air/gas flow studies. The Hot-wire anemometer consists of a fine wire heated by electric current. When placed in a fluid stream, the hot-wire loses heat to the fluid by forced convection. In forced convection, energy transfer is due to molecular motion imposed by an extraneous force moving fluid parcels. When the hot-wire is in "equilibrium", the rate of heat input to the wire is equal to the rate of heat loss at the wire ends. The equality between heat input and heat loss is the basis for King s equation, which relates the electrical parameters of the hot-wire to the flow parameters of the fluid. Hot-wire anemometry is based on convective heat transfer from a heated wire element placed in a fluid flow. Any change in the fluid flow condition that affects the heat transfer from the heated element will be detected virtually instantaneously by a constant-temperature Hot-wire anemometry system. The system implemented for this research is the IFA 300. The system is a fully-integrated, thermal anemometer-based system that measures mean and fluctuating velocity components in air, water, and other fluids. It also measures turbulence and makes localized temperature measurements. A constant-temperature anemometer is a bridge and amplifier circuit that controls a tiny wire at constant temperature. As a fluid flow passes over the heated sensor, the amplifier senses the bridge off-balance and adjusts the voltage to the top of the bridge, keeping the bridge in balance. The voltage on top of the bridge can then be related to the velocity of the flow. The bridge voltage is sensitive to temperature as well as velocity and so the built-in thermocouple circuit can be attached to a thermocouple that can measure the fluid temperature. Additional information is included in the original extended abstract.

Development of automatic through-insulation welding for microelectric interconnections

NASA Technical Reports Server (NTRS)

Arnett, J. C.

1972-01-01

The capability to automatically route, remove insulation from, and weld small-diameter solid conductor wire is presented. This would facilitate the economical small-quantity production of complex miniature electronic assemblies. An engineering model of equipment having this capability was developed and evaluated. Whereas early work in the use of welded magnet wire interconnections was concentrated on opposed electrode systems, and generally used heat to melt the wire insulation, the present method is based on a concentric electrode system and a wire feed system which splits the insulation by application of pressure prior to welding. The work deals with the design, fabrication, and evaluation testing of an improved version of this concentric electrode system. Two different approaches to feeding the wire to the concentric electrodes were investigated. It was concluded that the process is feasible for the interconnection of complex miniature electronic assemblies.

75 FR 60667 - Airworthiness Directives; Learjet Inc. Model 45 Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-01

.... This proposed AD would require a general visual inspection for damage of wiring (including chafing... result in a short circuit and the loss of systems associated with the wiring (including fire suppression..., which could result in the loss of systems associated with the wiring (including fire suppression...

Monitoring and evaluation of wire mesh forming life

NASA Astrophysics Data System (ADS)

Enemuoh, Emmanuel U.; Zhao, Ping; Kadlec, Alec

2018-03-01

Forming tables are used with stainless steel wire mesh conveyor belts to produce variety of products. The forming tables will typically run continuously for several days, with some hours of scheduled downtime for maintenance, cleaning and part replacement after several weeks of operation. The wire mesh conveyor belts show large variation in their remaining life due to associated variations in their nominal thicknesses. Currently the industry is dependent on seasoned operators to determine the replacement time for the wire mesh formers. The drawback of this approach is inconsistency in judgements made by different operators and lack of data knowledge that can be used to develop decision making system that will be more consistent with wire mesh life prediction and replacement time. In this study, diagnostic measurements about the health of wire mesh former is investigated and developed. The wire mesh quality characteristics considered are thermal measurement, tension property, gage thickness, and wire mesh wear. The results show that real time thermal sensor and wear measurements would provide suitable data for the estimation of wire mesh failure, therefore, can be used as a diagnostic parameter for developing structural health monitoring (SHM) system for stainless steel wire mesh formers.

The Influence of Pd-Doped Au Wire Bonding on HAZ Microstructure and Looping Profile in Micro-Electromechanical Systems (MEMS) Packaging

NASA Astrophysics Data System (ADS)

Ismail, Roslina; Omar, Ghazali; Jalar, Azman; Majlis, Burhanuddin Yeop

2015-07-01

Wire bonding processes has been widely adopted in micro-electromechanical systems (MEMS) packaging especially in biomedical devices for the integration of components. In the first process sequence in wire bonding, the zone along the wire near the melted tips is called the heat-affected zone (HAZ). The HAZ plays an important factor that influenced the looping profiles of wire bonding process. This paper investigates the effect of dopants on microstructures in the HAZ. One precent palladium (Pd) was added to the as-drawn 4N gold wire and annealed at 600°C. The addition of Pd was able to moderate the grain growth in the HAZ by retarding the heat propagation to the wire. In the formation of the looping profile, the first bending point of the looping is highly associated with the length of the HAZ. The alloyed gold wire (2N gold) has a sharp angle at a distance of about 30 m from the neck of the wire with a measured bending radius of about 40 mm and bending angle of about 40° clockwise from vertical axis, while the 4N gold wire bends at a longer distance. It also shows that the HAZ for 4N gold is longer than 2N gold wire.

47 CFR 32.2321 - Customer premises wiring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2321... 232, Station Connections, inside wiring subclass. (b) Embedded Customer Premises Wiring is that...

47 CFR 32.2321 - Customer premises wiring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2321... 232, Station Connections, inside wiring subclass. (b) Embedded Customer Premises Wiring is that...

Printed wiring board system programmer's manual

NASA Technical Reports Server (NTRS)

Brinkerhoff, C. D.

1973-01-01

The printed wiring board system provides automated techniques for the design of printed circuit boards and hybrid circuit boards. The system consists of four programs: (1) the preprocessor program combines user supplied data and pre-defined library data to produce the detailed circuit description data; (2) the placement program assigns circuit components to specific areas of the board in a manner that optimizes the total interconnection length of the circuit; (3) the organizer program assigns pin interconnections to specific board levels and determines the optimal order in which the router program should attempt to layout the paths connecting the pins; and (4) the router program determines the wire paths which are to be used to connect each input pin pair on the circuit board. This document is intended to serve as a programmer's reference manual for the printed wiring board system. A detailed description of the internal logic and flow of the printed wiring board programs is included.

46 CFR 129.340 - Cable and wiring.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Cable and wiring. 129.340 Section 129.340 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS ELECTRICAL INSTALLATIONS Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than...

Design and fabrication of a three-finger prosthetic hand using SMA muscle wires

NASA Astrophysics Data System (ADS)

Simone, Filomena; York, Alexander; Seelecke, Stefan

2015-03-01

Bio-inspired hand-like gripper systems based on shape memory alloy (SMA) wire actuation have the potential to enable a number of useful applications in, e.g., the biomedical field or industrial assembly systems. The inherent high energy density makes SMA solutions a natural choice for systems with lightweight, low noise and high force requirements, such as hand prostheses or robotic systems in a human/machine environment. The focus of this research is the development, design and realization of a SMA-actuated prosthetic hand prototype with three fingers. The use of thin wires (100 μm diameter) allows for high cooling rates and therefore fast movement of each finger. Grouping several small wires mechanically in parallel allows for high force actuation. To save space and to allow for a direct transmission of the motion to each finger, the SMA wires are attached directly within each finger, across each phalanx. In this way, the contraction of the wires will allow the movement of the fingers without the use of any additional gears. Within each finger, two different bundles of wires are mounted: protagonist ones that create bending movement and the antagonist ones that enable stretching of each phalanx. The resistance change in the SMA wires is measured during actuation, which allows for monitoring of the wire stroke and potentially the gripping force without the use of additional sensors. The hand is built with modern 3D-printing technologies and its performance while grasping objects of different size and shape is experimentally investigated illustrating the usefulness of the actuator concept.

Combustibility of Electrical Wire and Cable for Rail Rapid Transit Systems. Volume 1. Flammability.

DOT National Transportation Integrated Search

1983-05-01

The objective of this study was to examine the flammability of wires and cables used in rapid rail transit systems. The overall goal of the study was to quantify the fire properties of wires and cables in a manner so that the relative fire hazards co...

Combustibility of Electrical Wire and Cable for Rail Rapid Transit Systems. Volume 2. Toxicity.

DOT National Transportation Integrated Search

1983-05-01

The objective of this study was to examine the flammability of wires and cables used in rapid rail transit systems. The overall goal of the study was to quantify the fire properties of wires and cables in a manner so that the relative fire hazards co...

78 FR 22802 - Airworthiness Directives; the Boeing Company Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-17

... indication system and wiring on each engine; and repetitive operational checks of that installation to detect... wiring. Installation of a second locking gearbox 754 work-hours x $85 per hour = $0 $64,090 system. $64... proposed AD would require replacing certain relays and relay sockets, and doing wiring changes. For certain...

Interceptive Beam Diagnostics - Signal Creation and Materials Interactions

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

Plum, Michael; Spallation Neutron Source, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN

2004-11-10

The focus of this tutorial will be on interceptive beam diagnostics such as wire scanners, screens, and harps. We will start with an overview of the various ways beams interact with materials to create signals useful for beam diagnostics systems. We will then discuss the errors in a harp or wire scanner profile measurement caused by errors in wire position, number of samples, and signal errors. Finally we will apply our results to two design examples-the SNS wire scanner system and the SNS target harp.

Durability Evaluation of a Thin Film Sensor System With Enhanced Lead Wire Attachments on SiC/SiC Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Lei, Jih-Fen; Kiser, J. Douglas; Singh, Mrityunjay; Cuy, Mike; Blaha, Charles A.; Androjna, Drago

2000-01-01

An advanced thin film sensor system instrumented on silicon carbide (SiC) fiber reinforced SiC matrix ceramic matrix composites (SiC/SiC CMCs), was evaluated in a Mach 0.3 burner rig in order to determine its durability to monitor material/component surface temperature in harsh environments. The sensor system included thermocouples in a thin film form (5 microns thick), fine lead wires (75 microns diameter), and the bonds between these wires and the thin films. Other critical components of the overall system were the heavy, swaged lead wire cable (500 microns diameter) that contained the fine lead wires and was connected to the temperature readout, and ceramic attachments which were bonded onto the CMCs for the purpose of securing the lead wire cables, The newly developed ceramic attachment features a combination of hoops made of monolithic SiC or SiC/SiC CMC (which are joined to the test article) and high temperature ceramic cement. Two instrumented CMC panels were tested in a burner rig for a total of 40 cycles to 1150 C (2100 F). A cycle consisted of rapid heating to 1150 C (2100 F), a 5 minute hold at 1150 C (2100 F), and then cooling down to room temperature in 2 minutes. The thin film sensor systems provided repeatable temperature measurements for a maximum of 25 thermal cycles. Two of the monolithic SiC hoops debonded during the sensor fabrication process and two of the SiC/SiC CMC hoops failed during testing. The hoops filled with ceramic cement, however, showed no sign of detachment after 40 thermal cycle test. The primary failure mechanism of this sensor system was the loss of the fine lead wire-to-thin film connection, which either due to detachment of the fine lead wires from the thin film thermocouples or breakage of the fine wire.

46 CFR 183.340 - Cable and wiring requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... requirements. (a) If individual wires, rather than cable, are used in systems greater than 50 volts, the wire must be in conduit. (b) All cable and wire must: (1) Have stranded copper conductors with sufficient... constant representing the resistance of copper). I=Load current, in amperes. L=length of conductor from...

46 CFR 183.340 - Cable and wiring requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... requirements. (a) If individual wires, rather than cable, are used in systems greater than 50 volts, the wire must be in conduit. (b) All cable and wire must: (1) Have stranded copper conductors with sufficient... constant representing the resistance of copper). I=Load current, in amperes. L=length of conductor from...

46 CFR 183.340 - Cable and wiring requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... requirements. (a) If individual wires, rather than cable, are used in systems greater than 50 volts, the wire must be in conduit. (b) All cable and wire must: (1) Have stranded copper conductors with sufficient... constant representing the resistance of copper). I=Load current, in amperes. L=length of conductor from...

46 CFR 183.340 - Cable and wiring requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... requirements. (a) If individual wires, rather than cable, are used in systems greater than 50 volts, the wire must be in conduit. (b) All cable and wire must: (1) Have stranded copper conductors with sufficient... constant representing the resistance of copper). I=Load current, in amperes. L=length of conductor from...

Digital Systems Validation Handbook. Volume 2

DTIC Science & Technology

1989-02-01

power. 2. A grid of wires, solid sheet, or foil. 3. A wire from circuit to grounding block or case. 4. A wire from circuit to structure. 5. Shield...RETURN. (11) 1. Structure, for power, fault, and "discrete" circuits. 2. A grid of wires, solid sheet, or foil. 3. A wire from circuit load back to...TV (14) Television TWTD (13) Thin Wire Time Domain TX (5) Transmit U.K. (13,141 United Kingdom U.S. (14) United States UART (15) Universal Asynchronous

Next Generation Wiring

NASA Technical Reports Server (NTRS)

Medelius, Petro; Jolley, Scott; Fitzpatrick, Lilliana; Vinje, Rubiela; Williams, Martha; Clayton, LaNetra; Roberson, Luke; Smith, Trent; Santiago-Maldonado, Edgardo

2007-01-01

Wiring is a major operational component on aerospace hardware that accounts for substantial weight and volumetric space. Over time wire insulation can age and fail, often leading to catastrophic events such as system failure or fire. The next generation of wiring must be reliable and sustainable over long periods of time. These features will be achieved by the development of a wire insulation capable of autonomous self-healing that mitigates failure before it reaches a catastrophic level. In order to develop a self-healing insulation material, three steps must occur. First, methods of bonding similar materials must be developed that are capable of being initiated autonomously. This process will lead to the development of a manual repair system for polyimide wire insulation. Second, ways to initiate these bonding methods that lead to materials that are similar to the primary insulation must be developed. Finally, steps one and two must be integrated to produce a material that has no residues from the process that degrades the insulating properties of the final repaired insulation. The self-healing technology, teamed with the ability to identify and locate damage, will greatly improve reliability and safety of electrical wiring of critical systems. This paper will address these topics, discuss the results of preliminary testing, and remaining development issues related to self-healing wire insulation.

LANSCE-R WIRE-SCANNER ANALOG FRONT-END ELECTRONICS

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

Gruchalla, Michael E.

2011-01-01

A new AFE is being developed for the new LANSCE-R wire-scanner systems. The new AFE is implemented in a National Instruments Compact RIO (cRIO) module installed a BiRa 4U BiRIO cRIO chassis specifically designed to accommodate the cRIO crate and all the wire-scanner interface, control and motor-drive electronics. A single AFE module provides interface to both X and Y wire sensors using true DC coupled transimpedance amplifiers providing collection of the wire charge signals, real-time wire integrity verification using the normal dataacquisition system, and wire bias of 0V to +/-50V. The AFE system is designed to accommodate comparatively long macropulsesmore » (>1ms) with high PRF (>120Hz) without the need to provide timing signals. The basic AFE bandwidth is flat from true DC to 50kHz with a true first-order pole at 50kHz. Numeric integration in the cRIO FPGA provides real-time pulse-to-pulse numeric integration of the AFE signal to compute the total charge collected in each macropulse. This method of charge collection eliminates the need to provide synchronization signals to the wire-scanner AFE while providing the capability to accurately record the charge from long macropulses at high PRF.« less

Multifilament Cable Wire versus Conventional Wire for Sternal Closure in Patients Undergoing Major Cardiac Surgery.

PubMed

Oh, You Na; Ha, Keong Jun; Kim, Joon Bum; Jung, Sung-Ho; Choo, Suk Jung; Chung, Cheol Hyun; Lee, Jae Won

2015-08-01

Stainless steel wiring remains the most popular technique for primary sternal closure. Recently, a multifilament cable wiring system (Pioneer Surgical Technology Inc., Marquette, MI, USA) was introduced for sternal closure and has gained wide acceptance due to its superior resistance to tension. We aimed to compare conventional steel wiring to multifilament cable fixation for sternal closure in patients undergoing major cardiac surgery. Data were collected retrospectively on 1,354 patients who underwent sternal closure after major cardiac surgery, using either the multifilament cable wiring system or conventional steel wires between January 2009 and October 2010. The surgical outcomes of these two groups of patients were compared using propensity score matching based on 18 baseline patient characteristics. Propensity score matching yielded 392 pairs of patients in the two groups whose baseline profiles showed no significant differences. No significant differences between the two groups were observed in the rates of early mortality (2.0% vs. 1.3%, p=0.578), major wound complications requiring reconstruction (1.3% vs. 1.3%, p>0.99), minor wound complications (3.6% vs. 2.0%, p=0.279), or mediastinitis (0.8% vs. 1.0%, p=1.00). Patients in the multifilament cable group had fewer sternal bleeding events than those in the conventional wire group, but this tendency was not statistically significant (4.3% vs. 7.4%, p=0.068). The surgical outcomes of sternal closure using multifilament cable wires were comparable to those observed when conventional steel wires were used. Therefore, the multifilament cable wiring system may be considered a viable option for sternal closure in patients undergoing major cardiac surgery.

Investigation of lunar base thermal control system options

NASA Technical Reports Server (NTRS)

Ewart, Michael K.

1993-01-01

Long duration human exploration missions to the Moon will require active thermal control systems which have not previously been used in space. The two technologies which are most promising for long term lunar base thermal control are heat pumps and radiator shades. Recent trade-off studies at the Johnson Space Center have focused development efforts on the most promising heat pump and radiator shade technologies. Since these technologies are in the early stages of development and many parameters used in the study are not well defined, a parametric study was done to test the sensitivity to each assumption. The primary comparison factor in these studies was the total mass system, with power requirements included in the form of a mass penalty for power. Heat pump technologies considered were thermally driven heat pumps such as metal hydride, complex compound, absorption and zeolite. Also considered were electrically driven Stirling and vapor compression heat pumps. Radiator shade concepts considered included step shaped, V-shaped and parabolic (or catenary) shades and ground covers. A further trade study compared the masses of heat pump and radiator shade systems.

Description and Flight Test Results of the NASA F-8 Digital Fly-by-Wire Control System

NASA Technical Reports Server (NTRS)

1975-01-01

A NASA program to develop digital fly-by-wire (DFBW) technology for aircraft applications is discussed. Phase I of the program demonstrated the feasibility of using a digital fly-by-wire system for aircraft control through developing and flight testing a single channel system, which used Apollo hardware, in an F-8C airplane. The objective of Phase II of the program is to establish a technology base for designing practical DFBW systems. It will involve developing and flight testing a triplex digital fly-by-wire system using state-of-the-art airborne computers, system hardware, software, and redundancy concepts. The papers included in this report describe the Phase I system and its development and present results from the flight program. Man-rated flight software and the effects of lightning on digital flight control systems are also discussed.

Second NASA Workshop on Wiring for Space Applications

NASA Technical Reports Server (NTRS)

1994-01-01

This document contains the proceedings of the Second NASA Workshop on Wiring for Space Applications held at NASA LeRC in Cleveland, OH, 6-7 Oct. 1993. The workshop was sponsored by NASA Headquarters Code QW Office of Safety and Mission Quality, Technical Standards Division and hosted by NASA LeRC, Power Technology Division, Electrical Components and Systems Branch. The workshop addressed key technology issues in the field of electrical power wiring for space applications. Speakers from government, industry, and academia presented and discussed topics on arc tracking phenomena, wiring system design, insulation constructions, and system protection. Presentation materials provided by the various speakers are included in this document.

NEMA wire and cable standards development programs

NASA Astrophysics Data System (ADS)

Baird, Robert W.

1994-01-01

The National Electrical Manufacturers Association (NEMA) is the nation's largest trade association for manufacturers of electrical equipment. Its member companies produce components, end-use equipment and systems for the generation, transmission, distribution, control and use of electricity. The wire and cable division is presented in 6 sections: building wire and cable, fabricated conductors, flexible cords, high performance wire and cable, magnet wire, and power and control cable. Participating companies are listed.

Large scale generation of micro-droplet array by vapor condensation on mesh screen piece

PubMed Central

Xie, Jian; Xu, Jinliang; He, Xiaotian; Liu, Qi

2017-01-01

We developed a novel micro-droplet array system, which is based on the distinct three dimensional mesh screen structure and sintering and oxidation induced thermal-fluid performance. Mesh screen was sintered on a copper substrate by bonding the two components. Non-uniform residue stress is generated along weft wires, with larger stress on weft wire top location than elsewhere. Oxidation of the sintered package forms micro pits with few nanograsses on weft wire top location, due to the stress corrosion mechanism. Nanograsses grow elsewhere to show hydrophobic behavior. Thus, surface-energy-gradient weft wires are formed. Cooling the structure in a wet air environment nucleates water droplets on weft wire top location, which is more “hydrophilic” than elsewhere. Droplet size is well controlled by substrate temperature, air humidity and cooling time. Because warp wires do not contact copper substrate and there is a larger conductive thermal resistance between warp wire and weft wire, warp wires contribute less to condensation but function as supporting structure. The surface energy analysis of drops along weft wires explains why droplet array can be generated on the mesh screen piece. Because the commercial material is used, the droplet system is cost effective and can be used for large scale utilization. PMID:28054635

Large scale generation of micro-droplet array by vapor condensation on mesh screen piece.

PubMed

Xie, Jian; Xu, Jinliang; He, Xiaotian; Liu, Qi

2017-01-05

We developed a novel micro-droplet array system, which is based on the distinct three dimensional mesh screen structure and sintering and oxidation induced thermal-fluid performance. Mesh screen was sintered on a copper substrate by bonding the two components. Non-uniform residue stress is generated along weft wires, with larger stress on weft wire top location than elsewhere. Oxidation of the sintered package forms micro pits with few nanograsses on weft wire top location, due to the stress corrosion mechanism. Nanograsses grow elsewhere to show hydrophobic behavior. Thus, surface-energy-gradient weft wires are formed. Cooling the structure in a wet air environment nucleates water droplets on weft wire top location, which is more "hydrophilic" than elsewhere. Droplet size is well controlled by substrate temperature, air humidity and cooling time. Because warp wires do not contact copper substrate and there is a larger conductive thermal resistance between warp wire and weft wire, warp wires contribute less to condensation but function as supporting structure. The surface energy analysis of drops along weft wires explains why droplet array can be generated on the mesh screen piece. Because the commercial material is used, the droplet system is cost effective and can be used for large scale utilization.

Large scale generation of micro-droplet array by vapor condensation on mesh screen piece

NASA Astrophysics Data System (ADS)

Xie, Jian; Xu, Jinliang; He, Xiaotian; Liu, Qi

2017-01-01

We developed a novel micro-droplet array system, which is based on the distinct three dimensional mesh screen structure and sintering and oxidation induced thermal-fluid performance. Mesh screen was sintered on a copper substrate by bonding the two components. Non-uniform residue stress is generated along weft wires, with larger stress on weft wire top location than elsewhere. Oxidation of the sintered package forms micro pits with few nanograsses on weft wire top location, due to the stress corrosion mechanism. Nanograsses grow elsewhere to show hydrophobic behavior. Thus, surface-energy-gradient weft wires are formed. Cooling the structure in a wet air environment nucleates water droplets on weft wire top location, which is more “hydrophilic” than elsewhere. Droplet size is well controlled by substrate temperature, air humidity and cooling time. Because warp wires do not contact copper substrate and there is a larger conductive thermal resistance between warp wire and weft wire, warp wires contribute less to condensation but function as supporting structure. The surface energy analysis of drops along weft wires explains why droplet array can be generated on the mesh screen piece. Because the commercial material is used, the droplet system is cost effective and can be used for large scale utilization.

PCACE- PERSONAL COMPUTER AIDED CABLING ENGINEERING

NASA Technical Reports Server (NTRS)

Billitti, J. W.

1994-01-01

A computerized interactive harness engineering program has been developed to provide an inexpensive, interactive system which is designed for learning and using an engineering approach to interconnection systems. PCACE is basically a database system that stores information as files of individual connectors and handles wiring information in circuit groups stored as records. This directly emulates the typical manual engineering methods of data handling, thus making the user interface to the program very natural. Data files can be created, viewed, manipulated, or printed in real time. The printed ouput is in a form ready for use by fabrication and engineering personnel. PCACE also contains a wide variety of error-checking routines including connector contact checks during hardcopy generation. The user may edit existing harness data files or create new files. In creating a new file, the user is given the opportunity to insert all the connector and harness boiler plate data which would be part of a normal connector wiring diagram. This data includes the following: 1) connector reference designator, 2) connector part number, 3) backshell part number, 4) cable reference designator, 5) cable part number, 6) drawing revision, 7) relevant notes, 8) standard wire gauge, and 9) maximum circuit count. Any item except the maximum circuit count may be left blank, and any item may be changed at a later time. Once a file is created and organized, the user is directed to the main menu and has access to the file boiler plate, the circuit wiring records, and the wiring records index list. The organization of a file is such that record zero contains the connector/cable boiler plate, and all other records contain circuit wiring data. Each wiring record will handle a circuit with as many as nine wires in the interface. The record stores the circuit name and wire count and the following data for each wire: 1) wire identifier, 2) contact, 3) splice, 4) wire gauge if different from standard, 5) wire/group type, 6) wire destination, and 7) note number. The PCACE record structure allows for a wide variety of wiring forms using splices and shields, yet retains sufficient structure to maintain ease of use. PCACE is written in TURBO Pascal 3.0 and has been implemented on IBM PC, XT, and AT systems under DOS 3.1 with a memory of 512K of 8 bit bytes, two floppy disk drives, an RGB monitor, and a printer with ASCII control characters. PCACE was originally developed in 1983, and the IBM version was released in 1986.

Study on nondestructive detection system based on x-ray for wire ropes conveyer belt

NASA Astrophysics Data System (ADS)

Miao, Changyun; Shi, Boya; Wan, Peng; Li, Jie

2008-03-01

A nondestructive detection system based on X-ray for wire ropes conveyer belt is designed by X-ray detection technology. In this paper X-ray detection principle is analyzed, a design scheme of the system is presented; image processing of conveyer belt is researched and image processing algorithms are given; X-ray acquisition receiving board is designed with the use of FPGA and DSP; the software of the system is programmed by C#.NET on WINXP/WIN2000 platform. The experiment indicates the system can implement remote real-time detection of wire ropes conveyer belt images, find faults and give an alarm in time. The system is direct perceived, strong real-time and high accurate. It can be used for fault detection of wire ropes conveyer belts in mines, ports, terminals and other fields.

76 FR 10215 - Airworthiness Directives; Learjet Inc. Model 45 Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-24

... above. This AD requires a general visual inspection for damage of wiring (including chafing, pinched... the pilot and copilot circuit breaker panels caused by a short circuit between chafed wiring and the... misrouted wires, which could result in a short circuit and the loss of systems associated with the wiring...

Systems Engineering Approach To Ground Combat Vehicle Survivability In Urban Operations

DTIC Science & Technology

2016-09-01

extinguishing system (AFES), which uses fire wires to detect the presence of fires. The detection of fire automatically triggers the activation of the fire...corresponding wires and connection points also means that it can be more difficult for engineers to integrate distributed architecture systems onto...command signals to the missile via wires trailing behind the missile or via RF signals. See Figure 29 for an illustration of CLOS guidance. Since CLOS

Energetics and electronic properties of Pt wires of different topologies on monolayer MoSe{sub 2}

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

Jamdagni, Pooja, E-mail: j.poojaa1228@gmail.com; Ahluwalia, P. K.; Kumar, Ashok

2016-05-23

The energetics and electronic properties of different topology of Pt wires including linear, zigzag and ladder structures on MoSe{sub 2} monolayer have been investigated in the framework of density functional theory (DFT). The predicted order of stability of Pt wire on MoSe{sub 2} monolayer is found to be: linear > ladder > zigzag. Pt wires induce states near the Fermi level of MoSe{sub 2} that results into metallic characteristics of Pt-wire/MoSe{sub 2} assembled system. Valence band charge density signifies most of the contribution from Pt atoms near the Fermi energy of assembled wire/MoSe{sub 2} system. These findings are expected tomore » be important for the fabrication of devices based on MoSe{sub 2} layers for flexible nanoelectronics.« less

Advanced wiring technique and hardware application: Airplane and space vehicle

NASA Technical Reports Server (NTRS)

Ernst, H. L.; Eichman, C. D.

1972-01-01

An advanced wiring system is described which achieves the safety/reliability required for present and future airplane and space vehicle applications. Also, present wiring installation techniques and hardware are analyzed to establish existing problem areas. An advanced wiring system employing matrix interconnecting unit, plug to plug trunk bundles (FCC or ribbon cable) is outlined, and an installation study presented. A planned program to develop, lab test and flight test key features of these techniques and hardware as a part of the SST technology follow-on activities is discussed.

A biomechanical comparison of three sternotomy closure techniques.

PubMed

Cohen, David J; Griffin, Lanny V

2002-02-01

A biomechanical study of three sternotomy closure techniques (figure-of-eight stainless-steel wires, Pectofix Dynamic Sternal Fixation [DSF] stainless-steel plates, and figure-of-eight stainless-steel cables) was conducted to compare strength and stiffness variables in three clinically relevant loading modes (anterior-posterior shear, longitudinal shear, and lateral distraction). All tests were conducted on polyurethane foam sternal models that simulate the properties of cancellous bone. Each model was divided longitudinally and reconstructed using one of the sternotomy closure repair techniques. Tests were performed using a materials testing system that applies a continuously increasing amount of force in one direction to the model until it catastrophically breaks. A total of six trials of each fixation type in each of three test groups were prepared and tested, for a total of 54 tests. Strength and stiffness variables as well as a post-yield analysis of failure were evaluated. Sternums repaired using the DSF plate system are a more rigid construct than sternums repaired using the stainless-steel wires or cables in the distraction and transverse shear modes and they are not significantly different from sternums repaired with wires or cables in the longitudinal shear mode. The DSF plate system offers a 25% improvement in resistance to failure (yield) compared to wires when a transverse shear force is applied to the model. The cable system had a higher resistance to failure than the wires in all modes although the differences were not statistically significant. Additionally, the DSF plate system provides substantial reduction of the implant's cutting into the sternal model under loading as evidenced by the post-yield displacement when compared with either cables or wires for the distraction and longitudinal shear modes. For the transverse shear mode, the cables or wires would completely fail at the load for which cutting begins for the DSF. Both the DSF plate system and the stainless-steel cable system offer important advantages over figure-of-eight wire for sternal closure.

Cable Bundle Wire Derating

NASA Technical Reports Server (NTRS)

Lundquist, Ray A.; Leidecker, Henning

1998-01-01

The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: 3.7 amps per wire, bundle of 15 or more wires, 70 C environment, and vacuum of 10(exp -5) torr or less. To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.

Droplet monitoring probe

NASA Technical Reports Server (NTRS)

Baughman, J. R.; Thys, P. C.

1973-01-01

A droplet monitoring system is disclosed for analysis of mixed-phase fluid flow in development of gas turbines. The system uses a probe comprising two electrical wires spaced a known distance apart and connected at one end to means for establishing a dc potential between the wires. A drop in the fluid stream momentarily contacting both wires simultaneously causes and electrical signal which is amplified, detected and counted.

77 FR 58424 - Drucker, Inc., DynaMotive Energy Systems Corp., and Gate to Wire Solutions, Inc., Order of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-20

... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] Drucker, Inc., DynaMotive Energy Systems Corp., and Gate to Wire Solutions, Inc., Order of Suspension of Trading September 18, 2012. It appears to the... that there is a lack of current and accurate information concerning the securities of Gate to Wire...

Virtual Instrument Systems in Reality (VISIR) for Remote Wiring and Measurement of Electronic Circuits on Breadboard

ERIC Educational Resources Information Center

Tawfik, M.; Sancristobal, E.; Martin, S.; Gil, R.; Diaz, G.; Colmenar, A.; Peire, J.; Castro, M.; Nilsson, K.; Zackrisson, J.; Hakansson, L.; Gustavsson, I.

2013-01-01

This paper reports on a state-of-the-art remote laboratory project called Virtual Instrument Systems in Reality (VISIR). VISIR allows wiring and measuring of electronic circuits remotely on a virtual workbench that replicates physical circuit breadboards. The wiring mechanism is developed by means of a relay switching matrix connected to a PCI…

The 80 kV electrostatic wire septum for AmPS

NASA Astrophysics Data System (ADS)

Vanderlinden, A.; Bijleveld, J. H. M.; Rookhuizen, H. Boer; Bruinsma, P. J. T.; Heine, E.; Lassing, P.; Prins, E.

The characteristics of the wire septum for the Amsterdam Pulse Stretcher (AmPS) are summarized. In the extraction process of the AmPS the extracted beam is intercepted from the circulating beam by the 1 m long electrostatic wire septum. For a bending angle of 4.4 mrad, the maximum anode voltage is 80 kV. The system developed consists of a wire spacing of 0.65 mm between tungsten wires of 50 micrometers diameter. Stainless steel spring wires, bent in a half cylindrical carrier, stretch the septum wires two by two. Prototype tests were successful up to an anode voltage of 120 kV.

Mountain Plains Learning Experience Guide: Electrical Wiring. Course: Electrical Wiring Rough-In.

ERIC Educational Resources Information Center

Arneson, R.; And Others

One of two individualized courses included in an electrical wiring curriculum, this course covers electrical installations that are generally hidden within the structure. The course is comprised of four units: (1) Outlet and Switch Boxes, (2) Wiring, (3) Service Entrance, and (4) Signal and Low Voltage Systems. Each unit begins with a Unit…

Transport electron through a quantum wire by side-attached asymmetric quantum-dot rings

NASA Astrophysics Data System (ADS)

Rostami, A.; Zabihi, S.; Rasooli S., H.; Seyyedi, S. K.

2011-12-01

The electronic conductance at zero temperature through a quantum wire with side-attached asymmetric quantum ring (as a scatter system) is theoretically studied using the non-interacting Anderson tunneling Hamiltonian method. We show that the asymmetric configuration of QD- scatter system strongly impresses the amplitude and spectrum of quantum wire nanostructure transmission characteristics. It is shown that whenever the balanced number of quantum dots in two rings is substituted by unbalanced scheme, the number of forbidden mini-bands in quantum wire conductance increases and QW-nanostructure electronic conductance contains rich spectral properties due to appearance of the new anti-resonance and resonance points in spectrum. Considering the suitable gap between nano-rings can strengthen the amplitude of new resonant peaks in the QW conductance spectrum. The proposed asymmetric quantum ring scatter system idea in this paper opens a new insight on designing quantum wire nano structure for given electronic conductance.

Design of power cable grounding wire anti-theft monitoring system

NASA Astrophysics Data System (ADS)

An, Xisheng; Lu, Peng; Wei, Niansheng; Hong, Gang

2018-01-01

In order to prevent the serious consequences of the power grid failure caused by the power cable grounding wire theft, this paper presents a GPRS based power cable grounding wire anti-theft monitoring device system, which includes a camera module, a sensor module, a micro processing system module, and a data monitoring center module, a mobile terminal module. Our design utilize two kinds of methods for detecting and reporting comprehensive image, it can effectively solve the problem of power and cable grounding wire box theft problem, timely follow-up grounded cable theft events, prevent the occurrence of electric field of high voltage transmission line fault, improve the reliability of the safe operation of power grid.

Crystal-Phase Quantum Wires: One-Dimensional Heterostructures with Atomically Flat Interfaces.

PubMed

Corfdir, Pierre; Li, Hong; Marquardt, Oliver; Gao, Guanhui; Molas, Maciej R; Zettler, Johannes K; van Treeck, David; Flissikowski, Timur; Potemski, Marek; Draxl, Claudia; Trampert, Achim; Fernández-Garrido, Sergio; Grahn, Holger T; Brandt, Oliver

2018-01-10

In semiconductor quantum-wire heterostructures, interface roughness leads to exciton localization and to a radiative decay rate much smaller than that expected for structures with flat interfaces. Here, we uncover the electronic and optical properties of the one-dimensional extended defects that form at the intersection between stacking faults and inversion domain boundaries in GaN nanowires. We show that they act as crystal-phase quantum wires, a novel one-dimensional quantum system with atomically flat interfaces. These quantum wires efficiently capture excitons whose radiative decay gives rise to an optical doublet at 3.36 eV at 4.2 K. The binding energy of excitons confined in crystal-phase quantum wires is measured to be more than twice larger than that of the bulk. As a result of their unprecedented interface quality, these crystal-phase quantum wires constitute a model system for the study of one-dimensional excitons.

A Software Suite for Testing SpaceWire Devices and Networks

NASA Astrophysics Data System (ADS)

Mills, Stuart; Parkes, Steve

2015-09-01

SpaceWire is a data-handling network for use on-board spacecraft, which connects together instruments, mass-memory, processors, downlink telemetry, and other on-board sub-systems. SpaceWire is simple to implement and has some specific characteristics that help it support data-handling applications in space: high-speed, low-power, simplicity, relatively low implementation cost, and architectural flexibility making it ideal for many space missions. SpaceWire provides high-speed (2 Mbits/s to 200 Mbits/s), bi-directional, full-duplex data-links, which connect together SpaceWire enabled equipment. Data-handling networks can be built to suit particular applications using point-to-point data-links and routing switches. STAR-Dundee’s STAR-System software stack has been designed to meet the needs of engineers designing and developing SpaceWire networks and devices. This paper describes the aims of the software and how those needs were met.

Heartbeat-based error diagnosis framework for distributed embedded systems

NASA Astrophysics Data System (ADS)

Mishra, Swagat; Khilar, Pabitra Mohan

2012-01-01

Distributed Embedded Systems have significant applications in automobile industry as steer-by-wire, fly-by-wire and brake-by-wire systems. In this paper, we provide a general framework for fault detection in a distributed embedded real time system. We use heartbeat monitoring, check pointing and model based redundancy to design a scalable framework that takes care of task scheduling, temperature control and diagnosis of faulty nodes in a distributed embedded system. This helps in diagnosis and shutting down of faulty actuators before the system becomes unsafe. The framework is designed and tested using a new simulation model consisting of virtual nodes working on a message passing system.

Heartbeat-based error diagnosis framework for distributed embedded systems

NASA Astrophysics Data System (ADS)

Mishra, Swagat; Khilar, Pabitra Mohan

2011-12-01

Distributed Embedded Systems have significant applications in automobile industry as steer-by-wire, fly-by-wire and brake-by-wire systems. In this paper, we provide a general framework for fault detection in a distributed embedded real time system. We use heartbeat monitoring, check pointing and model based redundancy to design a scalable framework that takes care of task scheduling, temperature control and diagnosis of faulty nodes in a distributed embedded system. This helps in diagnosis and shutting down of faulty actuators before the system becomes unsafe. The framework is designed and tested using a new simulation model consisting of virtual nodes working on a message passing system.

Cable Bundle Wire Derating

NASA Technical Reports Server (NTRS)

Lundquist, Ray A.; Leidecker, Henning

1999-01-01

The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 degree C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: (1) 3.7 amps per wire (2) bundle of 15 or more wires (3) 70 C environment (4) vacuum of 10(exp -5) torr or less To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.

Cable Bundle Wire Derating

NASA Technical Reports Server (NTRS)

Lundquist, Ray A.; Leidecker, Henning

1998-01-01

The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: (1) 3.7 amps per wire; (2) bundle of 15 or more wires; (3) 70 C environment: and (4) vacuum of 10(exp -5) torr or less. To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.

Wire rope tension control of hoisting systems using a robust nonlinear adaptive backstepping control scheme.

PubMed

Zhu, Zhen-Cai; Li, Xiang; Shen, Gang; Zhu, Wei-Dong

2018-01-01

This paper concerns wire rope tension control of a double-rope winding hoisting system (DRWHS), which consists of a hoisting system employed to realize a transportation function and an electro-hydraulic servo system utilized to adjust wire rope tensions. A dynamic model of the DRWHS is developed in which parameter uncertainties and external disturbances are considered. A comparison between simulation results using the dynamic model and experimental results using a double-rope winding hoisting experimental system is given in order to demonstrate accuracy of the dynamic model. In order to improve the wire rope tension coordination control performance of the DRWHS, a robust nonlinear adaptive backstepping controller (RNABC) combined with a nonlinear disturbance observer (NDO) is proposed. Main features of the proposed combined controller are: (1) using the RNABC to adjust wire rope tensions with consideration of parameter uncertainties, whose parameters are designed online by adaptive laws derived from Lyapunov stability theory to guarantee the control performance and stability of the closed-loop system; and (2) introducing the NDO to deal with uncertain external disturbances. In order to demonstrate feasibility and effectiveness of the proposed controller, experimental studies have been conducted on the DRWHS controlled by an xPC rapid prototyping system. Experimental results verify that the proposed controller exhibits excellent performance on wire rope tension coordination control compared with a conventional proportional-integral (PI) controller and adaptive backstepping controller. Copyright © 2017 ISA. All rights reserved.

KIM-1 interface adapter to 3-wire teletype systems

NASA Technical Reports Server (NTRS)

Burhans, R. W.

1976-01-01

The KIM-1 circuit designed for use with a full duplex isolated 4 terminal system is described. Operation of the circuit with a 3 wire system in conjunction with a single +5v supply interface is discussed.

Preliminary Design of an Autonomous Amphibious System

DTIC Science & Technology

2016-09-01

changing vehicle dynamics will require innovative new autonomy algorithms. The developed software architecture, drive-by- wire kit, and supporting...COMMUNICATIONS ARCHITECTURE .................................................12 3.3 DRIVE-BY- WIRE DESIGN...SOFTWARE MATURATION PLANS ......................................................17 4.2 DRIVE-BY- WIRE PLANNED REFINEMENT

75 FR 60614 - Airworthiness Directives; The Boeing Company Model 747-400, 747-400D, and 747-400F Series Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-01

... source outside the FQIS to the densitometer wiring from causing failure of the FQIS densitometer... wiring of the other systems as a result of implementing the actions required by this AD. Boeing requests... are implemented, then no further actions are required to separate the FQIS wire from the wiring of...

Strength of cerclage fixation systems: a biomechanical study.

PubMed

Incavo, S J; Difazio, F; Wilder, D

1990-11-01

This study examined the load to failure ratio and stiffness of eight different cerclage techniques commonly used in the clinical management of fractures. For a single-loop cerclage, titanium cable was the strongest, while stainless steel wire secured with a commercial tightener was the weakest (P < 0.05). When a single-loop configuration is necessary (i.e. trochanteric attachment) a cable system is superior to cerclage wiring. A double-wrap of either cable or wire was considerably stronger than any single-wrap cerclage technique and stronger than two cerclage wires (P < 0.05). Copyright © 1990. Published by Elsevier Ltd.

A Comparison of Zero Mean Strain Rotating Beam Fatigue Test Methods for Nitinol Wire

NASA Astrophysics Data System (ADS)

Norwich, Dennis W.

2014-07-01

Zero mean strain rotating beam fatigue testing has become the standard for comparing the fatigue properties of Nitinol wire. Most commercially available equipment consists of either a two-chuck or a chuck and bushing system, where the wire length and center-to-center axis distance determine the maximum strain on the wire. For the two-chuck system, the samples are constrained at either end of the wire, and both chucks are driven at the same speed. For the chuck and bushing system, the sample is constrained at one end in a chuck and rides freely in a bushing at the other end. These equivalent systems will both be herein referred to as Chuck-to-Chuck systems. An alternate system uses a machined test block with a specific radius to guide the wire at a known strain during testing. In either system, the test parts can be immersed in a temperature-controlled fluid bath to eliminate any heating effect created in the specimen due to dissipative processes during cyclic loading (cyclic stress induced the formation of martensite) Wagner et al. ( Mater. Sci. Eng. A, 378, p 105-109, 1). This study will compare the results of the same starting material tested with each system to determine if the test system differences affect the final results. The advantages and disadvantages of each system will be highlighted and compared. The factors compared will include ease of setup, operator skill level required, consistency of strain measurement, equipment test limits, and data recovery and analysis. Also, the effect of test speed on the test results for each system will be investigated.

DNA G-Wire Formation Using an Artificial Peptide is Controlled by Protease Activity.

PubMed

Usui, Kenji; Okada, Arisa; Sakashita, Shungo; Shimooka, Masayuki; Tsuruoka, Takaaki; Nakano, Shu-Ichi; Miyoshi, Daisuke; Mashima, Tsukasa; Katahira, Masato; Hamada, Yoshio

2017-11-16

The development of a switching system for guanine nanowire (G-wire) formation by external signals is important for nanobiotechnological applications. Here, we demonstrate a DNA nanostructural switch (G-wire <--> particles) using a designed peptide and a protease. The peptide consists of a PNA sequence for inducing DNA to form DNA-PNA hybrid G-quadruplex structures, and a protease substrate sequence acting as a switching module that is dependent on the activity of a particular protease. Micro-scale analyses via TEM and AFM showed that G-rich DNA alone forms G-wires in the presence of Ca 2+ , and that the peptide disrupted this formation, resulting in the formation of particles. The addition of the protease and digestion of the peptide regenerated the G-wires. Macro-scale analyses by DLS, zeta potential, CD, and gel filtration were in agreement with the microscopic observations. These results imply that the secondary structure change (DNA G-quadruplex <--> DNA/PNA hybrid structure) induces a change in the well-formed nanostructure (G-wire <--> particles). Our findings demonstrate a control system for forming DNA G-wire structures dependent on protease activity using designed peptides. Such systems hold promise for regulating the formation of nanowire for various applications, including electronic circuits for use in nanobiotechnologies.

Computer-assisted design of flux-cored wires

NASA Astrophysics Data System (ADS)

Dubtsov, Yu N.; Zorin, I. V.; Sokolov, G. N.; Antonov, A. A.; Artem'ev, A. A.; Lysak, V. I.

2017-02-01

The algorithm and description of the AlMe-WireLaB software for the computer-assisted design of flux-cored wires are introduced. The software functionality is illustrated with the selection of the components for the flux-cored wire, ensuring the acquisition of the deposited metal of the Fe-Cr-C-Mo-Ni-Ti-B system. It is demonstrated that the developed software enables the technologically reliable flux-cored wire to be designed for surfacing, resulting in a metal of an ordered composition.

Modelling of structural flexiblity in multibody railroad vehicle systems

NASA Astrophysics Data System (ADS)

Escalona, José L.; Sugiyama, Hiroyuki; Shabana, Ahmed A.

2013-07-01

This paper presents a review of recent research investigations on the computer modelling of flexible bodies in railroad vehicle systems. The paper will also discuss the influence of the structural flexibility of various components, including the wheelset, the truck frames, tracks, pantograph/catenary systems, and car bodies, on the dynamics of railroad vehicles. While several formulations and computer techniques for modelling structural flexibility are discussed in this paper, a special attention is paid to the floating frame of reference formulation which is widely used and leads to reduced-order finite-element models for flexible bodies by employing component modes synthesis techniques. Other formulations and numerical methods such as semi-analytical approaches, absolute nodal coordinate formulation, finite-segment method, boundary elements method, and discrete elements method are also discussed. This investigation is motivated by the fact that the structural flexibility can have a significant effect on the overall dynamics of railroad vehicles, ride comfort, vibration suppression and noise level reduction, lateral stability, track response to vehicle forces, stress analysis, wheel-rail contact forces, wear and crashworthiness.

Molecular Spintronics: Theory of Spin-Dependent Electron Transport in Fe/BDT/Fe Molecular Wire Systems

NASA Astrophysics Data System (ADS)

Dalgleish, Hugh; Kirczenow, George

2004-03-01

Metal/Molecule/Metal junction systems forming molecular wires are currently the focus of intense study. Recently, spin-dependent electron transport in molecular wires with magnetic Ni electrodes has been studied theoretically, and spin-valve effects have been predicted.* Here we explore theoretically another magnetic molecular wire system, namely, ferromagnetic Fe nano-contacts bridged with 1,4-benzene-dithiolate (BDT). We estimate the essential structural and electronic parameters for this system based on ab initio density functional calculations (DFT) for some simple model systems involving thiol groups and Fe clusters as well as semi-empirical considerations and the known electronic structure of bulk Fe. We then use Lippmann-Schwinger and Green's function techniques together with the Landauer formalism to study spin-dependent transport. *E. G. Emberly and G. Kirczenow, Chem. Phys. 281, 311 (2002); R. Pati, L. Senapati, P.M. Ajayan and S.K. Nayak, Phys. Rev. B68, 100407 (2003).

21. VIEW OF MIANUS RIVER RAILROAD BRIDGE LOOKING NORTHEAST FROM ...

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

21. VIEW OF MIANUS RIVER RAILROAD BRIDGE LOOKING NORTHEAST FROM THE REMAINS OF THE COS COB POWER PLANT COALING DOCK. THE BRIDGE IS A ROLLING LIFT BASCULE TYPE BUILT IN 1894-1895. NOTE THE ABSENCE OF CATENARY OVER THE CHANNEL AND THE METHOD OF CARRYING POWER FEED OVER THE RIVER ON THE HIGH TOWERS ADJACENT TO THE LIFT SECTION OF THE BRIDGE. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

17. VIEW OF ANCHOR BRIDGE NUMBER 310 LOOKING EAST ALONG ...

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

17. VIEW OF ANCHOR BRIDGE NUMBER 310 LOOKING EAST ALONG THE MAIN LINE TRACK LOCATED TO THE NORTH OF THE COS COB POWER PLANT. ANCHOR BRIDGES LOCATED AT TWO MILE INTERVALS WITHSTAND CATENARY TENSION AND PROVIDE A PLATFORM FOR MOUNTING OIL FILLED CIRCUIT BREAKERS, LIGHTNING ARRESTORS AND OTHER ELECTRICAL EQUIPMENT. THE ROOF OF THE LOAD DISPATCHER'S TOWER CAN BE SEEN DIRECTLY BEHIND THE RIGHT SIDE OF THE BRIDGE. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

Flywheel system using wire-wound rotor

DOEpatents

Chiao, Edward Young; Bender, Donald Arthur; Means, Andrew E.; Snyder, Philip K.

2016-06-07

A flywheel is described having a rotor constructed of wire wound onto a central form. The wire is prestressed, thus mitigating stresses that occur during operation. In another aspect, the flywheel incorporates a low-loss motor using electrically non-conducting permanent magnets.

Characterization and application of Shape Memory Alloy wires for micro and meso positioning systems

NASA Astrophysics Data System (ADS)

Khan, Afzal

The properties of Shape Memory Alloy (SMA) wires are determined by experimentation, and previously used experimental equipment contributes to measurement errors in data. In this study, various characterization experiments are designed and carried out using a precision characterization instrument for shape memory alloy wires to determine the properties and parameters of the alloy. These experiments demonstrate the behavior of SMA wires under different thermal and loading conditions as they occur in actuation applications. As SMA wires go through phase transformation, a significant amount of contraction force is produced. This actuation force has been used in bias spring actuators and differential actuators. In this dissertation, the force generated during the twinning of martensite is used to actuate positioning systems with small displacements at the micrometer level. A micropositioning system is designed and tested that has a positioning accuracy of about +/-0.15 mum. A relation between the current input and the displacement output is determined for the specific preload. The transformation force generated during the phase change from martensite to austenite is used as an actuation force for a second positioning system that uses linear bearing with a displacement range of about a millimeter. This positioning system actuated with a single nitinol wire and guided by symmetric parallel diaphragm flexures, was designed and tested. The actuation is repeatable to about +/-15 mum with variation of about +/-5 mum in postion at steady temperature.

Third NASA Workshop on Wiring for Space Applications

NASA Technical Reports Server (NTRS)

Hammoud, Ahmad (Compiler); Stavnes, Mark (Compiler)

1995-01-01

This workshop addressed key technology issues in the field of electrical power wiring for space applications, and transferred information and technology related to space wiring for use in government and commercial applications. Speakers from space agencies, U.S. Federal labs, industry, and academia presented program overviews and discussed topics on arc tracking phenomena, advancements in insulation materials and constructions, and new wiring system topologies.

Safe Emergency Evacuation From Tall Structures

NASA Technical Reports Server (NTRS)

Stephan, E. S.

1984-01-01

Emergency egress system allows people to be evacuated quickly from tall structures. New emergency system applicable to rescues from fires in tall hotels and other buildings. System consists of basket on slide wire. Basket descends by gravity on sloped slide wire staked to ground.

77 FR 33129 - Airworthiness Directives; The Boeing Company Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-05

... modify the fuel quantity indication system (FQIS) wiring or fuel tank systems to prevent development of..., 2012 (77 FR 12506). That NPRM proposed to require modifying the fuel quantity indication system wiring or fuel tank systems to prevent development of an ignition source inside the center fuel tank. That...

14 CFR 25.1713 - Fire protection: EWIS.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Electrical Wiring Interconnection Systems (EWIS) § 25.1713... used during emergency procedures must be fire resistant. (c) Insulation on electrical wire and electrical cable, and materials used to provide additional protection for the wire and cable, installed in...

Wire winding increases lifetime of oxide coated cathodes

NASA Technical Reports Server (NTRS)

Kerslake, W.; Vargo, D.

1965-01-01

Refractory-metal heater base wound with a thin refractory metal wire increases the longevity of oxide-coated cathodes. The wire-wound unit is impregnated with the required thickness of metal oxide. This cathode is useful in magnetohydrodynamic systems and in electron tubes.

Multilayer radiation shield

DOEpatents

Urbahn, John Arthur; Laskaris, Evangelos Trifon

2009-06-16

A power generation system including: a generator including a rotor including a superconductive rotor coil coupled to a rotatable shaft; a first prime mover drivingly coupled to the rotatable shaft; and a thermal radiation shield, partially surrounding the rotor coil, including at least a first sheet and a second sheet spaced apart from the first sheet by centripetal force produced by the rotatable shaft. A thermal radiation shield for a generator including a rotor including a super-conductive rotor coil including: a first sheet having at least one surface formed from a low emissivity material; and at least one additional sheet having at least one surface formed from a low emissivity material spaced apart from the first sheet by centripetal force produced by the rotatable shaft, wherein each successive sheet is an incrementally greater circumferential arc length and wherein the centripetal force shapes the sheets into a substantially catenary shape.

NASA requirements and applications environments for electrical power wiring

NASA Technical Reports Server (NTRS)

Stavnes, Mark W.; Hammoud, Ahmad N.

1992-01-01

Serious problems can occur from insulation failures in the wiring harnesses of aerospace vehicles. In most recorded incidents, the failures have been identified to be the result of arc tracking, the propagation of an arc along wiring bundles through degradation of insulation. Propagation of the arc can lead to the loss of the entire wiring harness and the functions which it supports. While an extensive database of testing for arc track resistant wire insulations has been developed for aircraft applications, the counterpart requirements for spacecraft are very limited. The electrical, thermal, mechanical, chemical, and operational requirements for specification and testing of candidate wiring systems for spacecraft applications is presented.

Apollo display and keyboard unit (DSKY) used on F-8 DFBW

NASA Technical Reports Server (NTRS)

1996-01-01

The display and keyboard (DSKY) unit used on the F-8 Digital Fly-By-Wire (DFBW) aircraft during Phase I of the fly-by-wire program. Warning lights are in the upper left section, displays in the upper right, and the keyboard is in the lower section. The Apollo flight-control system used in Phase I of the DFBW program had been used previously on the Lunar Module and was incredibly reliable. The DSKY was one element of the system. Also part of the fly-by-wire control system was the inertial platform. Both the computer and the inertial platform required a cooling system that used liquid nitrogen to keep the system within temperature limits. Should the primary flight control system fail, a backup system using three analog computers would automatically take over. The F-8 DFBW had no manual backup. The F-8 Digital Fly-By-Wire (DFBW) flight research project validated the principal concepts of all-electric flight control systems now used on nearly all modern high-performance aircraft and on military and civilian transports. The first flight of the 13-year project was on May 25, 1972, with research pilot Gary E. Krier at the controls of a modified F-8C Crusader that served as the testbed for the fly-by-wire technologies. The project was a joint effort between the NASA Flight Research Center, Edwards, California, (now the Dryden Flight Research Center) and Langley Research Center. It included a total of 211 flights. The last flight was December 16, 1985, with Dryden research pilot Ed Schneider at the controls. The F-8 DFBW system was the forerunner of current fly-by-wire systems used in the space shuttles and on today's military and civil aircraft to make them safer, more maneuverable, and more efficient. Electronic fly-by-wire systems replaced older hydraulic control systems, freeing designers to design aircraft with reduced in-flight stability. Fly-by-wire systems are safer because of their redundancies. They are more maneuverable because computers can command more frequent adjustments than a human pilot can. For airliners, computerized control ensures a smoother ride than a human pilot alone can provide. Digital-fly-by-wire is more efficient because it is lighter and takes up less space than the hydraulic systems it replaced. This either reduces the fuel required to fly or increases the number of passengers or pounds of cargo the aircraft can carry. Digital fly-by-wire is currently used in a variety of aircraft ranging from F/A-18 fighters to the Boeing 777. The DFBW research program is considered one of the most significant and most successful NASA aeronautical programs since the inception of the agency. F-8 aircraft were built originally for the U.S. Navy by LTV Aerospace of Dallas, Texas. The aircraft had a wingspan of 35 feet, 2 inches; was 54 feet, 6 inches long; and was powered by a Pratt & Whitney J57 turbojet engine.

Magnetization reversal modes in fourfold Co nano-wire systems

NASA Astrophysics Data System (ADS)

Blachowicz, T.; Ehrmann, A.

2015-09-01

Magnetic nano-wire systems are, as well as other patterned magnetic structures, of special interest for novel applications, such as magnetic storage media. In these systems, the coupling between neighbouring magnetic units is most important for the magnetization reversal process of the complete system, leading to a variety of magnetization reversal mechanisms. This article examines the influence of the magnetic material on hysteresis loop shape, coercive field, and magnetization reversal modes. While iron nano-wire systems exhibit flat or one-step hysteresis loops, systems consisting of cobalt nano-wires show hysteresis loops with several longitudinal steps and transverse peaks, correlated to a rich spectrum of magnetization reversal mechanisms. We show that changing the material parameters while the system geometry stays identical can lead to completely different hysteresis loops and reversal modes. Thus, especially for finding magnetic nano-systems which can be used as quaternary or even higher-order storage devices, it is rational to test several materials for the planned systems. Apparently, new materials may lead to novel and unexpected behaviour - and can thus result in novel functionalities.

Image Capture and Display Based on Embedded Linux

NASA Astrophysics Data System (ADS)

Weigong, Zhang; Suran, Di; Yongxiang, Zhang; Liming, Li

For the requirement of building a highly reliable communication system, SpaceWire was selected in the integrated electronic system. There was a need to test the performance of SpaceWire. As part of the testing work, the goal of this paper is to transmit image data from CMOS camera through SpaceWire and display real-time images on the graphical user interface with Qt in the embedded development platform of Linux & ARM. A point-to-point mode of transmission was chosen; the running result showed the two communication ends basically reach a consensus picture in succession. It suggests that the SpaceWire can transmit the data reliably.

Application of vision measurements for modal analysis of wires for the purpose of overhead transmission lines monitoring

NASA Astrophysics Data System (ADS)

Mendrok, Krzysztof; Dworakowski, Ziemowit; Holak, Krzysztof; Kohut, Piotr

2017-05-01

Overhead transmission power lines are still one of the crucial elements of electro-energetic system. There are obvious advantages of using overhead transmission in the distribution of electricity. The amount of energy transported through a power line is determined by the distance between the wire and the ground or other objects placed beneath it (eg. trees). This distance is not fixed and depends on the overhang of the wire. This, in turn, is determined by many factors such as ambient temperature, humidity, precipitation, the value of current flowing through the wire. In order to optimize the wires electrical load, the monitoring of that overhang is required. One way to measure it is the non-contact measurement by vision system. It has the advantage, that using high-speed cameras respectively it also allows for vibration measurement and analysis of dynamic performance. That is very important while the wires are susceptible to the influence of wind, and the resulting vibrations interfere with the correct measurement of the overhang. The paper presents the results of vision measurements of the system vibrations and modal analysis carried out on their basis. The study was conducted on a specially made laboratory stand.

49 CFR 236.108 - Insulation resistance tests, wires in trunking and cables.

Code of Federal Regulations, 2014 CFR

2014-10-01

... cables. 236.108 Section 236.108 Transportation Other Regulations Relating to Transportation (Continued... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES... Insulation resistance tests, wires in trunking and cables. (a) Insulation resistance of wires and cables...

49 CFR 236.108 - Insulation resistance tests, wires in trunking and cables.

Code of Federal Regulations, 2012 CFR

2012-10-01

... cables. 236.108 Section 236.108 Transportation Other Regulations Relating to Transportation (Continued... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES... Insulation resistance tests, wires in trunking and cables. (a) Insulation resistance of wires and cables...

49 CFR 236.108 - Insulation resistance tests, wires in trunking and cables.

Code of Federal Regulations, 2013 CFR

2013-10-01

... cables. 236.108 Section 236.108 Transportation Other Regulations Relating to Transportation (Continued... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES... Insulation resistance tests, wires in trunking and cables. (a) Insulation resistance of wires and cables...

Fine-Filament MgB2 Superconductor Wire

NASA Technical Reports Server (NTRS)

Cantu, Sherrie

2015-01-01

Hyper Tech Research, Inc., has developed fine-filament magnesium diboride (MgB2) superconductor wire for motors and generators used in turboelectric aircraft propulsion systems. In Phase I of the project, Hyper Tech demonstrated that MgB2 multifilament wires (<10 micrometers) could reduce alternating current (AC) losses that occur due to hysteresis, eddy currents, and coupling losses. The company refined a manufacturing method that incorporates a magnesium-infiltration process and provides a tenfold enhancement in critical current density over wire made by a conventional method involving magnesium-boron powder mixtures. Hyper Tech also improved its wire-drawing capability to fabricate fine multifilament strands. In Phase II, the company developed, manufactured, and tested the wire for superconductor and engineering current density and AC losses. Hyper Tech also fabricated MgB2 rotor coil packs for a superconducting generator. The ultimate goal is to enable low-cost, round, lightweight, low-AC-loss superconductors for motor and generator stator coils operating at 25 K in next-generation turboelectric aircraft propulsion systems.

Dissipation-driven phase transitions in superconducting wires

NASA Astrophysics Data System (ADS)

Lobos, Alejandro; Iucci, Aníbal; Müller, Markus; Giamarchi, Thierry

2010-03-01

Narrow superconducting wires with diameter dξ0 (where ξ0 is the bulk superconducting coherence length) are quasi-1D systems in which fluctuations of the order parameter strongly affect low-temperature properties. Indeed, fluctuations cause the magnitude of the order parameter to temporarily vanish at some point along the wire, allowing its phase to slip by 2π, and to produce finite resistivity for all temperatures below Tc. In this work, we show that a weak coupling to a diffusive metallic film reinforces superconductivity in the wire through a quench of phase fluctuations. We analyze the effective phase-only action of the system by a perturbative renormalization-group and a self-consistent variational approach to obtain the critical points and phases at T=0. We predict a quantum phase transition towards a superconducting phase with long-range order as a function of the wire stiffness and coupling to the metal. Finally we discuss implications for the DC resistivity of the wire.

Inelastic fingerprints of hydrogen contamination in atomic gold wire systems

NASA Astrophysics Data System (ADS)

Frederiksen, Thomas; Paulsson, Magnus; Brandbyge, Mads

2007-03-01

We present series of first-principles calculations for both pure and hydrogen contaminated gold wire systems in order to investigate how such impurities can be detected. We show how a single H atom or a single H2 molecule in an atomic gold wire will affect forces and Au-Au atom distances under elongation. We further determine the corresponding evolution of the low-bias conductance as well as the inelastic contributions from vibrations. Our results indicate that the conductance of gold wires is only slightly reduced from the conductance quantum G0 = 2e2/h by the presence of a single hydrogen impurity, hence making it difficult to use the conductance itself to distinguish between various configurations. On the other hand, our calculations of the inelastic signals predict significant differences between pure and hydrogen contaminated wires, and, importantly, between atomic and molecular forms of the impurity. A detailed characterization of gold wires with a hydrogen impurity should therefore be possible from the strain dependence of the inelastic signals in the conductance.

A space release/deployment system actuated by shape memory wires

NASA Astrophysics Data System (ADS)

Fragnito, Marino; Vetrella and, Sergio

2002-11-01

In this paper, the design of an innovative hold down/release and deployment device actuated by shape memory wires, to be used for the first time for the S MA RT microsatellite solar wings is shown. The release and deployment mechanisms are actuated by a Shape Memory wire (Nitinol), which allows a complete symmetrical and synchronous release, in a very short time, of the four wings in pairs. The hold down kinematic mechanism is preloaded to avoid vibration nonlinearities and unwanted deployment at launch. The deployment mechanism is a simple pulley system. The stiffness of the deployed panel-hinge system needs to be dimensioned in order to meet the on-orbit requirement for attitude control. One-way roller clutches are used to keep the panel at the desired angle during the mission. An ad hoc software has been developed to simulate both the release and deployment operations, coupling the SMA wire behavior with the system mechanics.

Energy dissipation of composite multifilamentary superconductors for high-current ramp-field magnet applications

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

Gung, C.Y.

1993-01-01

Energy dissipation, which is also called AC loss, of a composite multifilamentary superconducting wire is one of the most fundamental concerns in building a stable superconducting magnet. Characterization and reduction of AC losses are especially important in designing a superconducting magnet for generating transient magnetic fields. The goal of this thesis is to improve the understanding of AC-loss properties of superconducting wires developed for high-current ramp-field magnet applications. The major tasks include: (1) building an advanced AC-loss measurement system, (2) measuring AC losses of superconducting wires under simulated pulse magnet operations, (3) developing an analytical model for explaining the newmore » AC-loss properties found in the experiment, and (4) developing a computational methodology for comparing AC losses of a superconducting wire with those of a cable for a superconducting pulse magnet. A new experimental system using an isothermal calorimetric method was designed and constructed to measure the absolute AC losses in a composite superconductor. This unique experimental setup is capable of measuring AC losses of a brittle Nb{sub 3}Sn wire carrying high AC current in-phase with a large-amplitude pulse magnetic field. Improvements of the accuracy and the efficiency of this method are discussed. Three different types of composite wire have been measured: a Nb{sub 3}Sn modified jelly-roll (MJR) internal-tin wire used in a prototype ohmic heating coil, a Nb{sub 3}Sn internal-tin wire developed for a fusion reactor ohmic heating coil, and a NbTi wire developed for the magnets in a particle accelerator. The cross sectional constructions of these wires represent typical commercial wires manufactured for pulse magnet applications.« less

Deformable 3D-2D registration for guiding K-wire placement in pelvic trauma surgery

NASA Astrophysics Data System (ADS)

Goerres, J.; Jacobson, M.; Uneri, A.; de Silva, T.; Ketcha, M.; Reaungamornrat, S.; Vogt, S.; Kleinszig, G.; Wolinsky, J.-P.; Osgood, G.; Siewerdsen, J. H.

2017-03-01

Pelvic Kirschner wire (K-wire) insertion is a challenging surgical task requiring interpretation of complex 3D anatomical shape from 2D projections (fluoroscopy) and delivery of device trajectories within fairly narrow bone corridors in proximity to adjacent nerves and vessels. Over long trajectories ( 10-25 cm), K-wires tend to curve (deform), making conventional rigid navigation inaccurate at the tip location. A system is presented that provides accurate 3D localization and guidance of rigid or deformable surgical devices ("components" - e.g., K-wires) based on 3D-2D registration. The patient is registered to a preoperative CT image by virtually projecting digitally reconstructed radiographs (DRRs) and matching to two or more intraoperative x-ray projections. The K-wire is localized using an analogous procedure matching DRRs of a deformably parametrized model for the device component (deformable known-component registration, or dKC-Reg). A cadaver study was performed in which a K-wire trajectory was delivered in the pelvis. The system demonstrated target registration error (TRE) of 2.1 ± 0.3 mm in location of the K-wire tip (median ± interquartile range, IQR) and 0.8 ± 1.4º in orientation at the tip (median ± IQR), providing functionality analogous to surgical tracking / navigation using imaging systems already in the surgical arsenal without reliance on a surgical tracker. The method offers quantitative 3D guidance using images (e.g., inlet / outlet views) already acquired in the standard of care, potentially extending the advantages of navigation to broader utilization in trauma surgery to improve surgical precision and safety.

Heave motion prediction of a large barge in random seas by using artificial neural network

NASA Astrophysics Data System (ADS)

Lee, Hsiu Eik; Liew, Mohd Shahir; Zawawi, Noor Amila Wan Abdullah; Toloue, Iraj

2017-11-01

This paper describes the development of a multi-layer feed forward artificial neural network (ANN) to predict rigid heave body motions of a large catenary moored barge subjected to multi-directional irregular waves. The barge is idealized as a rigid plate of finite draft with planar dimensions 160m (length) and 100m (width) which is held on station using a six point chain catenary mooring in 50m water depth. Hydroelastic effects are neglected from the physical model as the chief intent of this study is focused on large plate rigid body hydrodynamics modelling using ANN. Even with this assumption, the computational requirements for time domain coupled hydrodynamic simulations of a moored floating body is considerably costly, particularly if a large number of simulations are required such as in the case of response based design (RBD) methods. As an alternative to time consuming numerical hydrodynamics, a regression-type ANN model has been developed for efficient prediction of the barge's heave responses to random waves from various directions. It was determined that a network comprising of 3 input features, 2 hidden layers with 5 neurons each and 1 output was sufficient to produce acceptable predictions within 0.02 mean squared error. By benchmarking results from the ANN with those generated by a fully coupled dynamic model in OrcaFlex, it is demonstrated that the ANN is capable of predicting the barge's heave responses with acceptable accuracy.

Apparatus for disintegrating kidney stones

NASA Technical Reports Server (NTRS)

Angulo, E. D. (Inventor)

1984-01-01

The useful life of the wire probe in an ultrasonic kidney stone disintegration instrument is enhanced and prolonged by attaching the wire of the wire probe to the tip of an ultrasonic transducer by means of a clamping arrangement. Additionally, damping material is applied to the wire probe in the form of a damper tube through which the wire probe passes in the region adjacent the transducer tip. The damper tube extends outwardly from the transducer tip a predetermined distance, terminating in a resilient soft rubber joint. Also, the damper tube is supported intermediate its length by a support member. The damper system thus acts to inhibit lateral vibrations of the wire in the region of the transducer tip while providing little or no damping to the linear vibrations imparted to the wire by the transducer.

A reliability analysis tool for SpaceWire network

NASA Astrophysics Data System (ADS)

Zhou, Qiang; Zhu, Longjiang; Fei, Haidong; Wang, Xingyou

2017-04-01

A SpaceWire is a standard for on-board satellite networks as the basis for future data-handling architectures. It is becoming more and more popular in space applications due to its technical advantages, including reliability, low power and fault protection, etc. High reliability is the vital issue for spacecraft. Therefore, it is very important to analyze and improve the reliability performance of the SpaceWire network. This paper deals with the problem of reliability modeling and analysis with SpaceWire network. According to the function division of distributed network, a reliability analysis method based on a task is proposed, the reliability analysis of every task can lead to the system reliability matrix, the reliability result of the network system can be deduced by integrating these entire reliability indexes in the matrix. With the method, we develop a reliability analysis tool for SpaceWire Network based on VC, where the computation schemes for reliability matrix and the multi-path-task reliability are also implemented. By using this tool, we analyze several cases on typical architectures. And the analytic results indicate that redundancy architecture has better reliability performance than basic one. In practical, the dual redundancy scheme has been adopted for some key unit, to improve the reliability index of the system or task. Finally, this reliability analysis tool will has a directive influence on both task division and topology selection in the phase of SpaceWire network system design.

Tips of the dual-lumen microcatheter-facilitated reverse wire technique in percutaneous coronary interventions for markedly angulated bifurcated lesions.

PubMed

Nomura, Tetsuya; Kikai, Masakazu; Hori, Yusuke; Yoshioka, Kenichi; Kubota, Hiroshi; Miyawaki, Daisuke; Urata, Ryota; Sugimoto, Takeshi; Keira, Natsuya; Tatsumi, Tetsuya

2018-04-01

In practical settings of percutaneous coronary intervention (PCI), we sometimes encounter difficulty in introducing a guidewire (GW) to the markedly angulated side branch (SB), and the reverse wire technique is considered as a last resort to overcome such a situation. We analyzed 12 cases that underwent PCI with dual-lumen microcatheter-facilitated reverse wire technique between January 2013 and July 2016. We retrospectively investigated the lesion's characteristics and the details of the PCI procedures, and discussed tips about the use of this technique. The SB that exhibits both a smaller take-off angle and a larger carina angle is considered to be the most suitable candidate for this technique. The first step of this technique involves the delivery of the reverse wire system to the target bifurcation. However, most cases exhibit significant stenosis proximal to the bifurcation, which often hampers the delivery of the reverse wire system. Because the sharply curved reverse wire system is easier to pass the stenosis as compared to the roundly curved system, we recommend a sharp curve should be adopted for this technique. On the other hand, it is sure that device delivery is much easier on the GW with a round curve as compared to that with a sharp curve. Therefore, it is important to modify the details of this procedure on a case-by-case basis according to the lesion's characteristics.

Self-organization of mesoscopic silver wires by electrochemical deposition.

PubMed

Zhong, Sheng; Koch, Thomas; Walheim, Stefan; Rösner, Harald; Nold, Eberhard; Kobler, Aaron; Scherer, Torsten; Wang, Di; Kübel, Christian; Wang, Mu; Hahn, Horst; Schimmel, Thomas

2014-01-01

Long, straight mesoscale silver wires have been fabricated from AgNO3 electrolyte via electrodeposition without the help of templates, additives, and surfactants. Although the wire growth speed is very fast due to growth under non-equilibrium conditions, the wire morphology is regular and uniform in diameter. Structural studies reveal that the wires are single-crystalline, with the [112] direction as the growth direction. A possible growth mechanism is suggested. Auger depth profile measurements show that the wires are stable against oxidation under ambient conditions. This unique system provides a convenient way for the study of self-organization in electrochemical environments as well as for the fabrication of highly-ordered, single-crystalline metal nanowires.

[Current strategy in PCI for CTO].

PubMed

Asakura, Yasushi

2011-02-01

Recently, CTO PCI has come into wide use all over the world and it has been standardized. The 1st step is an antegrade approach using single wire. The 2nd strategy would be parallel wire technique. And the next would be a retrograde approach. In this method, retrograde wiring with Corsair is done at first. If it is successful, externalization is established using 300 cm wire, and this system is able to provide strong back-up support. If it fails, reverse CART technique is the next step. IVUS guided wiring is a last resort. The 2nd wire is manipulated with IVUS guidance. Now, initial success rate is more than 90% with these methods.

A Review of Gas-Cooled Reactor Concepts for SDI Applications

DTIC Science & Technology

1989-08-01

710 program .) Wire- Core Reactor (proposed by Rockwell). The wire- core reactor utilizes thin fuel wires woven between spacer wires to form an open...reactor is based on results of developmental studies of nuclear rocket propulsion systems. The reactor core is made up of annular fuel assemblies of...XE Addendum to Volume II. NERVA Fuel Development , Westinghouse Astronuclear Laboratory, TNR-230, July 15’ 1972. J I8- Rover Program Reactor Tests

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

77 FR 9518 - Airworthiness Directives; The Boeing Company Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-17

...) Installation of New Relay and Wiring Bundle Within 72 months after the effective date of this AD: Change the... and temperature control system (CACTCS). This AD requires doing certain wiring changes, installing a new relay and necessary wiring in the CACTCS, and performing an operational test of the cooling pack...

Aluminum Lithium Alloy 2195 Fusion Welding Improvements with New Filler Wire

NASA Technical Reports Server (NTRS)

Russell, Carolyn; Bjorkman, Gerry; McCool, Carolyn (Technical Monitor)

2000-01-01

A viewgraph presentation outlines NASA Marshall Space Flight Center, Lockheed Martin Michoud Space Systems, and McCook Metals' development an aluminum-copper weld filler wire for fusion welding 2195 aluminum lithium. The aluminum-copper based weld filler wire has been identified as B218, which is the result of six years of weld filler wire development funded by NASA, Lockheed Martin, and McCook Metals. The Super Lightweight External Tank for the NASA Space Shuttle Program consists of 2195 welded with 4043 aluminum-silicon weld filler wire. The B218 filler wire chemistry was developed to produce enhanced 2195 weld and repair weld mechanical properties. An initial characterization of the B218 weld filler wire was performed consisting of initial weld and repair weld evaluation comparing B218 and 4043. The testing involved room temperature and cryogenic tensile testing along with fracture toughness testing. B218 weld filler wire proved to produce enhanced initial and repair weld tensile and fracture properties over 4043. B218 weld filler wire has proved to be a superior weld filler wire for welding 2195 and other aluminum lithium alloys over 4043.

Interface for the rapid analysis of liquid samples by accelerator mass spectrometry

DOEpatents

Turteltaub, Kenneth; Ognibene, Ted; Thomas, Avi; Daley, Paul F; Salazar Quintero, Gary A; Bench, Graham

2014-02-04

An interface for the analysis of liquid sample having carbon content by an accelerator mass spectrometer including a wire, defects on the wire, a system for moving the wire, a droplet maker for producing droplets of the liquid sample and placing the droplets of the liquid sample on the wire in the defects, a system that converts the carbon content of the droplets of the liquid sample to carbon dioxide gas in a helium stream, and a gas-accepting ion source connected to the accelerator mass spectrometer that receives the carbon dioxide gas of the sample in a helium stream and introduces the carbon dioxide gas of the sample into the accelerator mass spectrometer.

An objectively-analyzed method for measuring the useful penetration of x-ray imaging systems.

PubMed

Glover, Jack L; Hudson, Lawrence T

2016-06-01

The ability to detect wires is an important capability of the cabinet x-ray imaging systems that are used in aviation security as well as the portable x-ray systems that are used by domestic law enforcement and military bomb squads. A number of national and international standards describe methods for testing this capability using the so called useful penetration test metric, where wires are imaged behind different thicknesses of blocking material. Presently, these tests are scored based on human judgments of wire visibility, which are inherently subjective. We propose a new method in which the useful penetration capabilities of an x-ray system are objectively evaluated by an image processing algorithm operating on digital images of a standard test object. The algorithm advantageously applies the Radon transform for curve parameter detection that reduces the problem of wire detection from two dimensions to one. The sensitivity of the wire detection method is adjustable and we demonstrate how the threshold parameter can be set to give agreement with human-judged results. The method was developed to be used in technical performance standards and is currently under ballot for inclusion in a US national aviation security standard.

An objectively-analyzed method for measuring the useful penetration of x-ray imaging systems

PubMed Central

Glover, Jack L.; Hudson, Lawrence T.

2016-01-01

The ability to detect wires is an important capability of the cabinet x-ray imaging systems that are used in aviation security as well as the portable x-ray systems that are used by domestic law enforcement and military bomb squads. A number of national and international standards describe methods for testing this capability using the so called useful penetration test metric, where wires are imaged behind different thicknesses of blocking material. Presently, these tests are scored based on human judgments of wire visibility, which are inherently subjective. We propose a new method in which the useful penetration capabilities of an x-ray system are objectively evaluated by an image processing algorithm operating on digital images of a standard test object. The algorithm advantageously applies the Radon transform for curve parameter detection that reduces the problem of wire detection from two dimensions to one. The sensitivity of the wire detection method is adjustable and we demonstrate how the threshold parameter can be set to give agreement with human-judged results. The method was developed to be used in technical performance standards and is currently under ballot for inclusion in a US national aviation security standard. PMID:27499586

An objectively-analyzed method for measuring the useful penetration of x-ray imaging systems

NASA Astrophysics Data System (ADS)

Glover, Jack L.; Hudson, Lawrence T.

2016-06-01

The ability to detect wires is an important capability of the cabinet x-ray imaging systems that are used in aviation security as well as the portable x-ray systems that are used by domestic law enforcement and military bomb squads. A number of national and international standards describe methods for testing this capability using the so called useful penetration test metric, where wires are imaged behind different thicknesses of blocking material. Presently, these tests are scored based on human judgments of wire visibility, which are inherently subjective. We propose a new method in which the useful penetration capabilities of an x-ray system are objectively evaluated by an image processing algorithm operating on digital images of a standard test object. The algorithm advantageously applies the Radon transform for curve parameter detection that reduces the problem of wire detection from two dimensions to one. The sensitivity of the wire detection method is adjustable and we demonstrate how the threshold parameter can be set to give agreement with human-judged results. The method was developed to be used in technical performance standards and is currently under ballot for inclusion in an international aviation security standard.

Polymer Chemistry

NASA Technical Reports Server (NTRS)

Williams, Martha; Roberson, Luke; Caraccio, Anne

2010-01-01

This viewgraph presentation describes new technologies in polymer and material chemistry that benefits NASA programs and missions. The topics include: 1) What are Polymers?; 2) History of Polymer Chemistry; 3) Composites/Materials Development at KSC; 4) Why Wiring; 5) Next Generation Wiring Materials; 6) Wire System Materials and Integration; 7) Self-Healing Wire Repair; 8) Smart Wiring Summary; 9) Fire and Polymers; 10) Aerogel Technology; 11) Aerogel Composites; 12) Aerogels for Oil Remediation; 13) KSC's Solution; 14) Chemochromic Hydrogen Sensors; 15) STS-130 and 131 Operations; 16) HyperPigment; 17) Antimicrobial Materials; 18) Conductive Inks Formulations for Multiple Applications; and 19) Testing and Processing Equipment.

A NASA/Industry/University Partnership for Development of Dual-Use Vibration Isolation Technology

NASA Technical Reports Server (NTRS)

Tinker, Michael L.

1994-01-01

A partnership is described that was formed as a result of a NASA university grant for the study of wire rope vibration isolation systems. Vibration isolators of this type are currently used in the Space Shuttle Orbiter and engine test facility, and have potential application in the international space station and other space vehicles. Wire rope isolators were considered for use on the Hubble Space Telescope and the military has used wire rope technology extensively. The desire of the wire rope industry to expand sales in commercial markets coupled with results of the prior NASA funded study, led to the formation of a partnership including NASA, the university involved in the research grant, and a small company that designs wire rope systems. Goals include the development of improved mathematical models and a designers handbook to facilitate the use of the new modeling tools.

Apparatus and method supporting wireless access to multiple security layers in an industrial control and automation system or other system

DOEpatents

Chen, Yu-Gene T.

2013-04-16

A method includes receiving a message at a first wireless node. The first wireless node is associated with a first wired network, and the first wired network is associated with a first security layer. The method also includes transmitting the message over the first wired network when at least one destination of the message is located in the first security layer. The method further includes wirelessly transmitting the message for delivery to a second wireless node when at least one destination of the message is located in a second security layer. The second wireless node is associated with a second wired network, and the second wired network is associated with the second security layer. The first and second security layers may be associated with different security paradigms and/or different security domains. Also, the message could be associated with destinations in the first and second security layers.

A Potential Pitfall in the Use of the Monorail System for Carotid Stenting

PubMed Central

Pereira, E.; Birnbaum, L.

2006-01-01

Summary The use of EPDs seems to be necessary for safe CAS. Though the monorail system may offer advantages for a single operator, we caution its use with certain aortic arch anatomies. In such anatomies, using an OTW system or at least a 300 cm filter wire or devices that support wire extension will remedy some complications, such as the loss of the guiding sheath. As in our case, the added advantage of a 300 cm filter wire enabled us to avoid a poor outcome or an emergency vascular surgery. PMID:20569594

A potential pitfall in the use of the monorail system for carotid stenting. A technical case report.

PubMed

Pereira, E; Birnbaum, L

2006-12-15

The use of EPDs seems to be necessary for safe CAS. Though the monorail system may offer advantages for a single operator, we caution its use with certain aortic arch anatomies. In such anatomies, using an OTW system or at least a 300 cm filter wire or devices that support wire extension will remedy some complications, such as the loss of the guiding sheath. As in our case, the added advantage of a 300 cm filter wire enabled us to avoid a poor outcome or an emergency vascular surgery.

Aging Aircraft 2005, The Joint NASA/FAA/DOD Conference on Aging Aircraft, Decision algorithms for Electrical Wiring Interconnect Systems (EWIS)Fault Detection

DTIC Science & Technology

2005-02-03

Aging Aircraft 2005 The 8th Joint NASA /FAA/DOD Conference on Aging Aircraft Decision Algorithms for Electrical Wiring Interconnect Systems (EWIS...SUBTITLE Aging Aircraft 2005, The 8th Joint NASA /FAA/DOD Conference on Aging Aircraft, Decision algorithms for Electrical Wiring Interconnect...UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) NASA Langley Research Center, 8W. Taylor St., M/S 190 Hampton, VA 23681 and NAVAIR

KSC-07pd3632

NASA Image and Video Library

2007-12-14

KENNEDY SPACE CENTER, FLA. -- On Launch Pad 39A, technicians overlook wires and monitoring equipment that will be used to validate the circuit on the test wiring from the electrical harness in space shuttle Atlantis' aft main engine compartment connected with the engine cut-off system. The test wiring leads from the tail mast on the mobile launcher platform to the interior where the Time Domain Reflectometry, or TDR, test equipment will be located to test the sensor system. Photo credit: NASA/Kim Shiflett

Steady-state analysis of a faulted three-phase four-wire system supplying induction motors with neutrals connected and other single-phase line-to-neutral loads

NASA Technical Reports Server (NTRS)

Wood, M. E.

1980-01-01

Four wire Wye connected ac power systems exhibit peculiar steady state fault characteristics when the fourth wire of three phase induction motors is connected. The loss of one phase of power source due to a series or shunt fault results in currents higher than anticipated on the remaining two phases. A theoretical approach to compute the fault currents and voltages is developed. A FORTRAN program is included in the appendix.

Electrodynamic Tethers. 1: Power Generator in LEO. 2: Thrust for Propulsion and Power Storage

NASA Technical Reports Server (NTRS)

Mccoy, J. E.

1984-01-01

An electrodynamic tether consists of a long insulated wire in space whose orbital motion cuts across lines of magnetic flux to produce an induce voltage that in typical low orbits averages about 200 v/km. Such a system should be capable of generating substantial electrical power, at the expense of IXB drag acting on its orbital energy. If a reverse current is driven against the induced voltage, the system should act as a motor producing IXB thrust. A reference system was designed, capable of generating 20 KW of power into an electrical load located anywhere along the wire at the expense of 2.6N (20,000 J/sec) drag on the wire. In an ideal system, the conversion between mechanical and electrical energy would reach 100% efficiency. In the actual system part of the 20 KW is lost to internal resistance of the wire, plasma and ionosphere, while the drag force is increased by residual air drag. The 20 KW PMG system as designed is estimated to provide 18.7 KW net power to the load at total drag loss of 20.4 KJ/sec, or an overall efficiency of 92%. Similar systems using heavier wire appear capable of producing power levels in excess of 1 Megawatt at voltages of 2-4 KV, with conversion efficiency between mechanical and electrical power better than 95%. The hollow cathode based system should be readily reversible from generator to motor operation by driving a reverse current using onboard power.

An EEG (electroencephalogram) recording system with carbon wire electrodes for simultaneous EEG-fMRI (functional magnetic resonance imaging) recording

PubMed Central

Negishi, Michiro; Abildgaard, Mark; Laufer, Ilan; Nixon, Terry; Constable, Robert Todd

2008-01-01

Simultaneous EEG-fMRI (Electroencephalography-functional Magnetic Resonance Imaging) recording provides a means for acquiring high temporal resolution electrophysiological data and high spatial resolution metabolic data of the brain in the same experimental runs. Carbon wire electrodes (not metallic EEG electrodes with carbon wire leads) are suitable for simultaneous EEG-fMRI recording, because they cause less RF (radio-frequency) heating and susceptibility artifacts than metallic electrodes. These characteristics are especially desirable for recording the EEG in high field MRI scanners. Carbon wire electrodes are also comfortable to wear during long recording sessions. However, carbon electrodes have high electrode-electrolyte potentials compared to widely used Ag/AgCl (silver/silver-chloride) electrodes, which may cause slow voltage drifts. This paper introduces a prototype EEG recording system with carbon wire electrodes and a circuit that suppresses the slow voltage drift. The system was tested for the voltage drift, RF heating, susceptibility artifact, and impedance, and was also evaluated in a simultaneous ERP (event-related potential)-fMRI experiment. PMID:18588913

46 CFR 111.105-17 - Wiring methods for hazardous locations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Wiring methods for hazardous locations. 111.105-17... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Hazardous Locations § 111.105-17 Wiring methods for... made with dust-tight cable entrance seals approved for the installation. [CGD 94-108, 61 FR 28284, June...

Randomized comparison of the magnetic navigation system vs. standard wires in the treatment of bifurcations.

PubMed

Ramcharitar, Steve; van der Giessen, Willem J; van der Ent, Martin; Serruys, Patrick W; van Geuns, Robert Jan

2011-06-01

Aims Randomly compare the magnetic navigation system (MNS) to standard guidewire techniques in managing bifurcating lesions. Methods and results Thirty-one consecutive patients with bifurcating lesions were randomized to cross the bifurcating vessels prior to treatment and thereafter the struts of deployed stents with either magnetic or standard guidewires. Crossing success, crossing/fluoroscopy times, and contrast media usage were directly compared. Similar times were noted in both the magnetic wire crossings (median, IQR; 68 s, 45-138 s vs. 59 s, 32-133 s) and fluoroscopic times (median, IQR; 62 s, 44-135 s vs. 55 s, 27-133 s) when compared with standard conventional wires passage through the deployed struts. The MNS successful crossings were 30/31 (96.8%) compared with 28/31 (90.0%) observed with the standard wires. Two previously failed standard wire cases were successfully crossed with magnetic guidewires. Conclusion In contemporary stented bifurcations, the MNS achieved equivalent crossing/fluoroscopy times through deployed stents struts and may be useful in salvaging failed standard wire cases.

Integrated Electrical Wire Insulation Repair System

NASA Technical Reports Server (NTRS)

Williams, Martha; Jolley, Scott; Gibson, Tracy; Parks, Steven

2013-01-01

An integrated system tool will allow a technician to easily and quickly repair damaged high-performance electrical wire insulation in the field. Low-melt polyimides have been developed that can be processed into thin films that work well in the repair of damaged polyimide or fluoropolymer insulated electrical wiring. Such thin films can be used in wire insulation repairs by affixing a film of this low-melt polyimide to the damaged wire, and heating the film to effect melting, flow, and cure of the film. The resulting repair is robust, lightweight, and small in volume. The heating of this repair film is accomplished with the use of a common electrical soldering tool that has been modified with a special head or tip that can accommodate the size of wire being repaired. This repair method can furthermore be simplified for the repair technician by providing replaceable or disposable soldering tool heads that have repair film already "loaded" and ready for use. The soldering tool heating device can also be equipped with a battery power supply that will allow its use in areas where plug-in current is not available

Amplification of Reynolds number dependent processes by wave distortion. [acoustic instability of liquid propellant rocket engines

NASA Technical Reports Server (NTRS)

Ventrice, M. B.; Fang, J. C.; Purdy, K. R.

1975-01-01

A system using a hot-wire transducer as an analog of a liquid droplet of propellant was employed to investigate the ingredients of the acoustic instability of liquid-propellant rocket engines. It was assumed that the combustion process was vaporization-limited and that the combustion chamber was acoustically similar to a closed-closed right-circular cylinder. Before studying the hot-wire closed-loop system (the analog system), a microphone closed-loop system, which used the response of a microphone as the source of a linear feedback exciting signal, was investigated to establish the characteristics of self-sustenance of acoustic fields. Self-sustained acoustic fields were found to occur only at resonant frequencies of the chamber. In the hot-wire closed-loop system, the response of hot-wire anemometer was used as the source of the feedback exciting signal. The self-sustained acoustic fields which developed in the system were always found to be harmonically distorted and to have as their fundamental frquency a resonant frequency for which there also existed a second resonant frequency which was approximately twice the fundamental frequency.

Development of automatic pre-tracking system for fillet weld based on laser trigonometry

NASA Astrophysics Data System (ADS)

Shen, Xiaoqin; Yu, Fusheng

2005-01-01

In this paper, an automatic fillet weld pre-tracking system for welding the work piece of lorry back boards with several bend in haul automobile is developed basing on laser trigonometry. The optical measuring head based on laser-PSD trigonometry is used as position sensor. It is placed in front of the traveling direction of welding wire to get the distances from welding wire to the two side boards of the welding lines, upper board and bottom board of the fillet weld respectively. A chip of AT89S52 is used as the micro controller in this system. The AC servomotors, ball-screws and straight guide rails constitute the sliding table to take welding wire move. The laser-PSD sensors pass through the vertical board, upper board and bottom board of the fillet weld when welding wire moves and then get the distance. The laser-PSD sensors output the analog signals. After A/D conversion, the digital signal is input into AT89S52 and calculated. Then the information of the position and lateral deviation of the welding wire when welding a certain position are gotten to control welding wires. So the weld pre-tracking for welding the work piece with long distance and large bend in haul automobile is realized. The position information is input into EEPROM to be saved for short time after handled by AT89S52. The information is as the welding position information as well as the speed adjusting data of the welding wire when it welds the several bend of the work piece. The practice indicates that this system has high pre-tracking precision, good anti-disturb ability, excellent reliability, easy operating ability and good adaptability to the field of production.

The mechatronic design of a fast wire scanner in IHEP U-70 accelerator

NASA Astrophysics Data System (ADS)

Baranov, V. T.; Makhov, S. S.; Savin, D. A.; Terekhov, V. I.

2016-10-01

This paper presents the mechatronic design of a fast wire scanner based on a servomotor. The design of the wire scanner is motivated by the need to measure the transverse profile of the high power proton and carbon beams at the IHEP U-70 accelerator. This paper formulates the requirements to the fast wire scanner system for the high intensity proton beam at the U-70 accelerator. The results on the design of electro-mechanical device for the wire scanner with a wire traveling speed 10-20 m/s are presented. The solution consists in a brushless servomotor and standard motor control electronics. High radiation levels in the accelerator enclosure dictate the use of a resolver as the position feedback element.

Shape memory alloy heat engines and energy harvesting systems

DOEpatents

Browne, Alan L; Johnson, Nancy L; Shaw, John Andrew; Churchill, Christopher Burton; Keefe, Andrew C; McKnight, Geoffrey P; Alexander, Paul W; Herrera, Guillermo A; Yates, James Ryan; Brown, Jeffrey W

2014-09-30

A heat engine includes a first rotatable pulley and a second rotatable pulley spaced from the first rotatable pulley. A shape memory alloy (SMA) element is disposed about respective portions of the pulleys at an SMA pulley ratio. The SMA element includes a first wire, a second wire, and a matrix joining the first wire and the second wire. The first wire and the second wire are in contact with the pulleys, but the matrix is not in contact with the pulleys. A timing cable is disposed about respective portions of the pulleys at a timing pulley ratio, which is different than the SMA pulley ratio. The SMA element converts a thermal energy gradient between the hot region and the cold region into mechanical energy.

Welding wire pressure sensor assembly

NASA Technical Reports Server (NTRS)

Morris, Timothy B. (Inventor); Milly, Peter F., Sr. (Inventor); White, J. Kevin (Inventor)

1994-01-01

The present invention relates to a device which is used to monitor the position of a filler wire relative to a base material being welded as the filler wire is added to a welding pool. The device is applicable to automated welding systems wherein nonconsumable electrode arc welding processes are utilized in conjunction with a filler wire which is added to a weld pool created by the electrode arc. The invention senses pressure deviations from a predetermined pressure between the filler wire and the base material, and provides electrical signals responsive to the deviations for actuating control mechanisms in an automatic welding apparatus so as to minimize the pressure deviation and to prevent disengagement of the contact between the filler wire and the base material.

Mechanization of and experience with a triplex fly-by-wire backup control system

NASA Technical Reports Server (NTRS)

Lock, W. P.; Petersen, W. R.; Whitman, G. B.

1976-01-01

A redundant three axis analog control system was designed and developed to back up a digital fly by wire control system for an F-8C airplane. The mechanization and operational experience with the backup control system, the problems involved in synchronizing it with the primary system, and the reliability of the system are discussed. The backup control system was dissimilar to the primary system, and it provided satisfactory handling through the flight envelope evaluated. Limited flight tests of a variety of control tasks showed that control was also satisfactory when the backup control system was controlled by a minimum displacement (force) side stick. The operational reliability of the F-8 digital fly by wire control system was satisfactory, with no unintentional downmodes to the backup control system in flight. The ground and flight reliability of the system's components is discussed.

[Contrast of Z-Pinch X-Ray Yield Measure Technique].

PubMed

Li, Mo; Wang, Liang-ping; Sheng, Liang; Lu, Yi

2015-03-01

Resistive bolometer and scintillant detection system are two mainly Z-pinch X-ray yield measure techniques which are based on different diagnostic principles. Contrasting the results from two methods can help with increasing precision of X-ray yield measurement. Experiments with different load material and shape were carried out on the "QiangGuang-I" facility. For Al wire arrays, X-ray yields measured by the two techniques were largely consistent. However, for insulating coating W wire arrays, X-ray yields taken from bolometer changed with load parameters while data from scintillant detection system hardly changed. Simulation and analysis draw conclusions as follows: (1) Scintillant detection system is much more sensitive to X-ray photons with low energy and its spectral response is wider than the resistive bolometer. Thus, results from the former method are always larger than the latter. (2) The responses of the two systems are both flat to Al plasma radiation. Thus, their results are consistent for Al wire array loads. (3) Radiation form planar W wire arrays is mainly composed of sub-keV soft X-ray. X-ray yields measured by the bolometer is supposed to be accurate because of the nickel foil can absorb almost all the soft X-ray. (4) By contrast, using planar W wire arrays, data from scintillant detection system hardly change with load parameters. A possible explanation is that while the distance between wires increases, plasma temperature at stagnation reduces and spectra moves toward the soft X-ray region. Scintillator is much more sensitive to the soft X-ray below 200 eV. Thus, although the total X-ray yield reduces with large diameter load, signal from the scintillant detection system is almost the same. (5) Both Techniques affected by electron beams produced by the loads.

Fast wire per wire X-ray data acquisition system for time-resolved small angle scattering experiments

NASA Astrophysics Data System (ADS)

Epstein, A.; Briquet-Laugier, F.; Sheldon, S.; Boulin, C.

2000-04-01

Most of the X-ray multi-wire gas detectors used at the EMBL Hamburg outstation for time-resolved studies of biological samples are readout, using the delay line method. The main disadvantage of such readout systems is their event rate limitation introduced by the delay line and the required time to digital conversion step. They also lack the possibility to deal with multiple events. To overcome these limitations, a new approach for the complete readout system was introduced. The new linear detection system is based on the wire per wire approach where each individual wire is associated to preamplifier/discriminator/counter electronics channel. High-density, front-end electronics were designed around a fast current sensitive preamplifier. An eight-channel board was designed to include the preamplifiers-discriminators and the differential ECL drivers output stages. The detector front-end consists of 25 boards directly mounted inside the detector assembly. To achieve a time framing resolution as short as 10 /spl mu/s, very fast histogramming is required. The only way to implement this for a high number of channels (200 in our case) is by using a distributed system. The digital part of the system consists of a crate controller, up to 16 acquisition boards (capable of handling fast histogramming for up to 32-channels each) and an optical-link board (based on the Cypress "Hot-Link" chip set). Both the crate controller and the acquisition boards are based on a standard RISC microcontroller (IDT R3081) plug-in board. At present, a dedicated CAMAC module which we developed is used to interface the digital front-end acquisition crate to the host via the optical link.

Preliminary system design study for a digital fly-by-wire flight control system for an F-8C aircraft

NASA Technical Reports Server (NTRS)

Seacord, C. L.; Vaughn, D. K.

1976-01-01

The design of a fly-by-wire control system having a mission failure probability of less than one millionth failures per flight hour is examined. Emphasis was placed on developing actuator configurations that would improve the system performance, and consideration of the practical aspects of sensor/computer and computer/actuator interface implementation. Five basic configurations were defined as appropriate candidates for the F-8C research aircraft. Options on the basic configurations were included to cover variations in flight sensors, redundancy levels, data transmission techniques, processor input/output methods, and servo actuator arrangements. The study results can be applied to fly by wire systems for transport aircraft in general and the space shuttle.

Stationary drag photocurrent caused by strong effective running wave in quantum wires: Quantization of current

NASA Astrophysics Data System (ADS)

Entin, M. V.; Magarill, L. I.

2010-02-01

The stationary current induced by a strong running potential wave in one-dimensional system is studied. Such a wave can result from illumination of a straight quantum wire with special grating or spiral quantum wire by circular-polarized light. The wave drags electrons in the direction correlated with the direction of the system symmetry and polarization of light. In a pure system the wave induces minibands in the accompanied system of reference. We study the effect in the presence of impurity scattering. The current is an interplay between the wave drag and impurity braking. It was found that the drag current is quantized when the Fermi level gets into energy gaps.

A numerical simulation of tooth movement by wire bending.

PubMed

Kojima, Yukio; Fukui, Hisao

2006-10-01

In orthodontic treatment, wires are bent and attached to teeth to move them via elastic recovery. To predict how a tooth will move, the initial force system produced from the wire is calculated. However, the initial force system changes as the tooth moves and may not be used to predict the final tooth position. The purpose of this study was to develop a comprehensive mechanical, 3-dimensional, numerical model for predicting tooth movement. Tooth movements produced by wire bending were simulated numerically. The teeth moved as a result of bone remodeling, which occurs in proportion to stress in the periodontal ligament. With an off-center bend, a tooth near the bending position was subjected to a large moment and tipped more noticeably than the other teeth. Also, a tooth far from the bending position moved slightly in the mesial or the distal direction. With the center V-bend, when the second molar was added as an anchor tooth, the tipping angle and the intrusion of the canine increased, and movement of the first molar was prevented. When a wire with an inverse curve of Spee was placed in the mandibular arch, the calculated tendency of vertical tooth movements was the same as the measured result. In these tooth movements, the initial force system changed as the teeth moved. Tooth movement was influenced by the size of the root surface area. Tooth movements produced by wire bending could be estimated. It was difficult to predict final tooth positions from the initial force system.

Metal muscles and nerves—a self-sensing SMA-actuated hand concept

NASA Astrophysics Data System (ADS)

Simone, F.; Rizzello, G.; Seelecke, S.

2017-09-01

Bio-inspired hand-like grippers actuated by Shape Memory Alloy (SMA) wires represent an emerging new technology with potential applications in many different fields, ranging from industrial assembly processes to biomedical systems. The inherently high energy density makes SMAs a natural choice for compact, lightweight, and silent actuator systems capable of producing a high amount of work, such as hand prostheses or robotic systems in industrial human/machine environments. In this work, a concept for a compact and versatile gripping system is developed, in which SMA wires are implemented as antagonistic muscles actuating an artificial hand with three fingers. In order to combine high gripping force with sufficient actuation speed, the muscle implementation pursues a multi-wire concept with several 0.1 mm diameter NiTi wires connected in parallel, in order to increase the surface-to-volume ratio for accelerated cooling. The paper starts with an illustration of the design concept of an individual 3-phalanx-finger, along with kinematic considerations for optimal placement of SMA wires. Three identical fingers are subsequently fabricated via 3D printing and assembled into a hand-like gripper. The maximum displacement of each finger phalanx is measured, and an average phalanxes dynamic responsiveness is evaluated. SMA self-sensing is documented by experiments relating the wires change in resistance to the finger motion. Several finger force measurements are also performed. The versatility of the gripper is finally documented by displaying a variety of achievable grasping configurations.

Structural Properties of Single-Strand Orthodontic Wires from a Proposed Alternative Standard Flexure Test.

DTIC Science & Technology

1984-01-01

structural system the orthodontic appliance consists intraorally of bands or bonded pads and the attached brackets , the arch wires, the ligatures, and any...RD-Ali5B 994 STRUCTURAL PROPERTIES OF SINGLE-STRAND ORTHODONTIC i/i WIRES FROM A PROPOSED__(U) AIR FORCE INST OF TECH WRIGHT-PATTERSON RFB OH M L... Orthodontic Wires From A Proposed Alternative - Standard Flexure Test 6. PERPOMING o1. REPORT NUMBER AUTNOR(e) I. CONTRACT O& GRANT NUMUER(a) Marion L

An interactive wire-wrap board layout program

NASA Technical Reports Server (NTRS)

Schlutsmeyer, A.

1987-01-01

An interactive computer-graphics-based tool for specifying the placement of electronic parts on a wire-wrap circuit board is presented. Input is a data file (currently produced by a commercial logic design system) which describes the parts used and their interconnections. Output includes printed reports describing the parts and wire paths, parts counts, placement lists, board drawing, and a tape to send to the wire-wrap vendor. The program should reduce the engineer's layout time by a factor of 3 to 5 as compared to manual methods.

Powerplexer

NASA Technical Reports Server (NTRS)

Woods, J. M. (Inventor)

1973-01-01

An electrical power distribution system is described for use in providing different dc voltage levels. A circuit is supplied with DC voltage levels and commutates pulses for timed intervals onto a pair of distribution wires. The circuit is driven by a command generator which places pulses on the wires in a timed sequence. The pair of wires extend to voltage strippers connected to the various loads. The voltage strippers each respond to the pulse dc levels on the pair of wires and form different output voltages communicated to each load.

Graphics enhanced computer emulation for improved timing-race and fault tolerance control system analysis. [of Centaur liquid-fuel booster

NASA Technical Reports Server (NTRS)

Szatkowski, G. P.

1983-01-01

A computer simulation system has been developed for the Space Shuttle's advanced Centaur liquid fuel booster rocket, in order to conduct systems safety verification and flight operations training. This simulation utility is designed to analyze functional system behavior by integrating control avionics with mechanical and fluid elements, and is able to emulate any system operation, from simple relay logic to complex VLSI components, with wire-by-wire detail. A novel graphics data entry system offers a pseudo-wire wrap data base that can be easily updated. Visual subsystem operations can be selected and displayed in color on a six-monitor graphics processor. System timing and fault verification analyses are conducted by injecting component fault modes and min/max timing delays, and then observing system operation through a red line monitor.

Problems with aging wiring in Naval aircraft

NASA Technical Reports Server (NTRS)

Campbell, Frank J.

1994-01-01

The Navy is experiencing a severe aircraft electrical wiring maintenance problem as a result of the extensive use of an aromatic polyimide insulation that is deteriorating at a rate that was unexpected when this wire was initially selected. This problem has significantly affected readiness, reliability, and safety and has greatly increased the cost of ownership of Naval aircraft. Failures in wire harnesses have exhibited arcing and burning that will propagate drastically, to the interruption of many electrical circuits from a fault initiated by the failure of deteriorating wires. There is an urgent need for a capability to schedule aircraft rewiring in an orderly manner with a logically derived determination of which aircraft have aged to the point of absolute necessity. Excessive maintenance was demonstrated to result from the accelerated aging due to the parameters of moisture, temperature, and strain that exist in the Naval Aircraft environment. Laboratory studies have demonstrated that MIL-W-81381 wire insulation when aged at high humidities followed the classical Arrhenius thermal aging relationship. In an extension of the project a multifactor formula was developed that is now capable of predicting life under varying conditions of these service parameters. An automated test system has also been developed to analyze the degree of deterioration that has occurred in wires taken from an aircraft in order to obtain an assessment of remaining life. Since it is both physically and financially impossible to replace the wiring in all the Navy's aircraft at once, this system will permit expedient scheduling so that those aircraft that are most probable to have wiring failure problems can be overhauled first.

Causes of failure with Szabo technique - an analysis of nine cases.

PubMed

Jain, Rajendra Kumar; Padmanabhan, T N C; Chitnis, Nishad

2013-01-01

The objective of this case series is to identify and define causes of failure of Szabo technique in rapid-exchange monorail system for ostial lesions. From March 2009 to March 2011, 42 patients with an ostial lesion were treated percutaneously at our institution using Szabo technique in a monorail stent system. All patients received unfractionated heparin during intervention. Loading dose of clopidogrel, followed by clopidogrel and aspirin was administered. In 57% of patients, drug-eluting stents were used and in 42.8% patients bare metal stents. The stent was advanced over both wires, the target wire and the anchor wire. The anchor wire, which was passed through the proximal trailing strut of the stent helps to achieve precise stenting. The procedure was considered to be successful if stent was placed precisely covering the lesion and without stent loss or anchor wire prolapsing. Of the total 42 patients, the procedure was successful in 33, while failed in 9. Majority of failures were due to wire entanglement, which was fixed successfully in 3 cases by removing and reinserting the anchor wire. Out of other three failures, in one stent dislodgment occurred, stent could not cross the lesion in one and in another anchor wire got looped and prolapsed into target vessel. This case series shows that the Szabo technique, in spite of some difficulties like wire entanglement, stent dislodgement and resistance during stent advancement, is a simple and feasible method for treating variety of ostial lesions precisely compared to conventional angioplasty. Copyright © 2013 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Causes of failure with Szabo technique – An analysis of nine cases

PubMed Central

Jain, Rajendra Kumar; Padmanabhan, T.N.C.; Chitnis, Nishad

2013-01-01

Objective The objective of this case series is to identify and define causes of failure of Szabo technique in rapid-exchange monorail system for ostial lesions. Methods and results From March 2009 to March 2011, 42 patients with an ostial lesion were treated percutaneously at our institution using Szabo technique in a monorail stent system. All patients received unfractionated heparin during intervention. Loading dose of clopidogrel, followed by clopidogrel and aspirin was administered. In 57% of patients, drug-eluting stents were used and in 42.8% patients bare metal stents. The stent was advanced over both wires, the target wire and the anchor wire. The anchor wire, which was passed through the proximal trailing strut of the stent helps to achieve precise stenting. The procedure was considered to be successful if stent was placed precisely covering the lesion and without stent loss or anchor wire prolapsing. Of the total 42 patients, the procedure was successful in 33, while failed in 9. Majority of failures were due to wire entanglement, which was fixed successfully in 3 cases by removing and reinserting the anchor wire. Out of other three failures, in one stent dislodgment occurred, stent could not cross the lesion in one and in another anchor wire got looped and prolapsed into target vessel. Conclusion This case series shows that the Szabo technique, in spite of some difficulties like wire entanglement, stent dislodgement and resistance during stent advancement, is a simple and feasible method for treating variety of ostial lesions precisely compared to conventional angioplasty. PMID:23809379

Correlating electronic transport to atomic structures in self-assembled quantum wires.

PubMed

Qin, Shengyong; Kim, Tae-Hwan; Zhang, Yanning; Ouyang, Wenjie; Weitering, Hanno H; Shih, Chih-Kang; Baddorf, Arthur P; Wu, Ruqian; Li, An-Ping

2012-02-08

Quantum wires, as a smallest electronic conductor, are expected to be a fundamental component in all quantum architectures. The electronic conductance in quantum wires, however, is often dictated by structural instabilities and electron localization at the atomic scale. Here we report on the evolutions of electronic transport as a function of temperature and interwire coupling as the quantum wires of GdSi(2) are self-assembled on Si(100) wire-by-wire. The correlation between structure, electronic properties, and electronic transport are examined by combining nanotransport measurements, scanning tunneling microscopy, and density functional theory calculations. A metal-insulator transition is revealed in isolated nanowires, while a robust metallic state is obtained in wire bundles at low temperature. The atomic defects lead to electron localizations in isolated nanowire, and interwire coupling stabilizes the structure and promotes the metallic states in wire bundles. This illustrates how the conductance nature of a one-dimensional system can be dramatically modified by the environmental change on the atomic scale. © 2012 American Chemical Society

Needleless electrospinning with twisted wire spinneret

NASA Astrophysics Data System (ADS)

Holopainen, Jani; Penttinen, Toni; Santala, Eero; Ritala, Mikko

2015-01-01

A needleless electrospinning setup named ‘Needleless Twisted Wire Electrospinning’ was developed. The polymer solution is electrospun from the surface of a twisted wire set to a high voltage and collected on a cylindrical collector around the wire. Multiple Taylor cones are simultaneously self-formed on the downward flowing solution. The system is robust and simple with no moving parts aside from the syringe pump used to transport the solution to the top of the wire. The structure and process parameters of the setup and the results on the preparation of polyvinyl pyrrolidone (PVP), hydroxyapatite (HA) and bioglass fibers with the setup are presented. PVP fiber sheets with areas of 40 × 120 cm2 and masses up to 1.15 g were prepared. High production rates of 5.23 g h-1 and 1.40 g h-1 were achieved for PVP and HA respectively. The major limiting factor of the setup is drying of the polymer solution on the wire during the electrospinning process which will eventually force to interrupt the process for cleaning of the wire. Possible solutions to this problem and other ways to develop the setup are discussed. The presented system provides a simple way to increase the production rate and area of fiber sheet as compared with the conventional needle electrospinning.

Performance of Continuous Quantum Thermal Devices Indirectly Connected to Environments

NASA Astrophysics Data System (ADS)

González, J.; Alonso, Daniel; Palao, José

2016-04-01

A general quantum thermodynamics network is composed of thermal devices connected to the environments through quantum wires. The coupling between the devices and the wires may introduce additional decay channels which modify the system performance with respect to the directly-coupled device. We analyze this effect in a quantum three-level device connected to a heat bath or to a work source through a two-level wire. The steady state heat currents are decomposed into the contributions of the set of simple circuits in the graph representing the master equation. Each circuit is associated with a mechanism in the device operation and the system performance can be described by a small number of circuit representatives of those mechanisms. Although in the limit of weak coupling between the device and the wire the new irreversible contributions can become small, they prevent the system from reaching the Carnot efficiency.

Research of x-ray nondestructive detector for high-speed running conveyor belt with steel wire ropes

NASA Astrophysics Data System (ADS)

Wang, Junfeng; Miao, Changyun; Wang, Wei; Lu, Xiaocui

2008-03-01

An X-ray nondestructive detector for high-speed running conveyor belt with steel wire ropes is researched in the paper. The principle of X-ray nondestructive testing (NDT) is analyzed, the general scheme of the X-ray nondestructive testing system is proposed, and the nondestructive detector for high-speed running conveyor belt with steel wire ropes is developed. The hardware of system is designed with Xilinx's VIRTEX-4 FPGA that embeds PowerPC and MAC IP core, and its network communication software based on TCP/IP protocol is programmed by loading LwIP to PowerPC. The nondestructive testing of high-speed conveyor belt with steel wire ropes and network transfer function are implemented. It is a strong real-time system with rapid scanning speed, high reliability and remotely nondestructive testing function. The nondestructive detector can be applied to the detection of product line in industry.

Design of measuring system for wire diameter based on sub-pixel edge detection algorithm

NASA Astrophysics Data System (ADS)

Chen, Yudong; Zhou, Wang

2016-09-01

Light projection method is often used in measuring system for wire diameter, which is relatively simpler structure and lower cost, and the measuring accuracy is limited by the pixel size of CCD. Using a CCD with small pixel size can improve the measuring accuracy, but will increase the cost and difficulty of making. In this paper, through the comparative analysis of a variety of sub-pixel edge detection algorithms, polynomial fitting method is applied for data processing in measuring system for wire diameter, to improve the measuring accuracy and enhance the ability of anti-noise. In the design of system structure, light projection method with orthogonal structure is used for the detection optical part, which can effectively reduce the error caused by line jitter in the measuring process. For the electrical part, ARM Cortex-M4 microprocessor is used as the core of the circuit module, which can not only drive double channel linear CCD but also complete the sampling, processing and storage of the CCD video signal. In addition, ARM microprocessor can complete the high speed operation of the whole measuring system for wire diameter in the case of no additional chip. The experimental results show that sub-pixel edge detection algorithm based on polynomial fitting can make up for the lack of single pixel size and improve the precision of measuring system for wire diameter significantly, without increasing hardware complexity of the entire system.

The Effects of Operational Parameters on a Mono-wire Cutting System: Efficiency in Marble Processing

NASA Astrophysics Data System (ADS)

Yilmazkaya, Emre; Ozcelik, Yilmaz

2016-02-01

Mono-wire block cutting machines that cut with a diamond wire can be used for squaring natural stone blocks and the slab-cutting process. The efficient use of these machines reduces operating costs by ensuring less diamond wire wear and longer wire life at high speeds. The high investment costs of these machines will lead to their efficient use and reduce production costs by increasing plant efficiency. Therefore, there is a need to investigate the cutting performance parameters of mono-wire cutting machines in terms of rock properties and operating parameters. This study aims to investigate the effects of the wire rotational speed (peripheral speed) and wire descending speed (cutting speed), which are the operating parameters of a mono-wire cutting machine, on unit wear and unit energy, which are the performance parameters in mono-wire cutting. By using the obtained results, cuttability charts for each natural stone were created on the basis of unit wear and unit energy values, cutting optimizations were performed, and the relationships between some physical and mechanical properties of rocks and the optimum cutting parameters obtained as a result of the optimization were investigated.

B218 Weld Filler Wire Characterization for Al-Li Alloy 2195

NASA Technical Reports Server (NTRS)

Bjorkman, Gerry; Russell, Carolyn

2000-01-01

NASA Marshall Space Flight Center, Lockheed Martin Space Systems- Michoud Operations, and McCook Metals have developed an aluminum-copper weld filler wire for fusion welding aluminum lithium alloy 2195. The aluminum-copper based weld filler wire has been identified as B218, a McCook Metals designation. B218 is the result of six years of weld filler wire development funded by NASA, Lockheed Martin, and McCook Metals. The filler wire chemistry was developed to produce enhanced 2195 weld and repair weld mechanical properties over the 4043 aluminum-silicon weld filler wire, which is currently used to weld 2195 on the Super Lightweight External Tank for the NASA Space Shuttle Program. An initial characterization was performed consisting of a repair weld evaluation using B218 and 4043 weld filler wires. The testing involved room temperature and cryogenic repair weld tensile testing along with fracture toughness testing. From the testing, B218 weld filler wire produce enhanced repair weld tensile strength, ductility, and fracture properties over 4043. B218 weld filler wire has proved to be a superior weld filler wire for welding aluminum lithium alloy 2195 over 4043.

A Novel Two-Wire Fast Readout Approach for Suppressing Cable Crosstalk in a Tactile Resistive Sensor Array

PubMed Central

Wu, Jianfeng; Wang, Yu; Li, Jianqing; Song, Aiguo

2016-01-01

For suppressing the crosstalk problem due to wire resistances and contacted resistances of the long flexible cables in tactile sensing systems, we present a novel two-wire fast readout approach for the two-dimensional resistive sensor array in shared row-column fashion. In the approach, two wires are used for every driving electrode and every sampling electrode in the resistive sensor array. The approach with a high readout rate, though it requires a large number of wires and many sampling channels, solves the cable crosstalk problem. We also verified the approach’s performance with Multisim simulations and actual experiments. PMID:27213373

Investigation of factors affecting the heater wire method of calibrating fine wire thermocouples

NASA Technical Reports Server (NTRS)

Keshock, E. G.

1972-01-01

An analytical investigation was made of a transient method of calibrating fine wire thermocouples. The system consisted of a 10 mil diameter standard thermocouple (Pt, Pt-13% Rh) and an 0.8 mil diameter chromel-alumel thermocouple attached to a 20 mil diameter electrically heated platinum wire. The calibration procedure consisted of electrically heating the wire to approximately 2500 F within about a seven-second period in an environment approximating atmospheric conditions at 120,000 feet. Rapid periodic readout of the standard and fine wire thermocouple signals permitted a comparison of the two temperature indications. An analysis was performed which indicated that the temperature distortion at the heater wire produced by the thermocouple junctions appears to be of negligible magnitude. Consequently, the calibration technique appears to be basically sound, although several practical changes which appear desirable are presented and discussed. Additional investigation is warranted to evaluate radiation effects and transient response characteristics.

Pull-pull position control of dual motor wire rope transmission.

PubMed

Guo, Quan; Jiao, Zongxia; Yan, Liang; Yu, Qian; Shang, Yaoxing

2016-08-01

Wire rope transmission is very efficient because of the small total moving object mass. The wire rope could only transmit pulling force. Therefore it has to be kept in a tightened state during transmission; in high speed applications the dynamic performance depends on the rope's stiffness, which can be adjusted by the wire rope tension. To improve the system dynamic performance output, this paper proposes a novel pull-pull method based on dual motors connected by wire ropes, for precise, high speed position control applications. The method can regulate target position and wire rope tension simultaneously. Wire ropes remain in a pre-tightening state at all times, which prevents the influence of elasticity and reduces the position tracking error in the changing direction process. Simulations and experiments were conducted; the results indicate that both position precision and superior dynamic performance can be synchronously achieved. The research is relevant to space craft precision pointing instruments.

Prediction of multi performance characteristics of wire EDM process using grey ANFIS

NASA Astrophysics Data System (ADS)

Kumanan, Somasundaram; Nair, Anish

2017-09-01

Super alloys are used to fabricate components in ultra-supercritical power plants. These hard to machine materials are processed using non-traditional machining methods like Wire cut electrical discharge machining and needs attention. This paper details about multi performance optimization of wire EDM process using Grey ANFIS. Experiments are designed to establish the performance characteristics of wire EDM such as surface roughness, material removal rate, wire wear rate and geometric tolerances. The control parameters are pulse on time, pulse off time, current, voltage, flushing pressure, wire tension, table feed and wire speed. Grey relational analysis is employed to optimise the multi objectives. Analysis of variance of the grey grades is used to identify the critical parameters. A regression model is developed and used to generate datasets for the training of proposed adaptive neuro fuzzy inference system. The developed prediction model is tested for its prediction ability.

46 CFR 183.340 - Cable and wiring requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... a manner as to avoid chafing and other damage. The use of plastic tie wraps must be limited to... requirements. (a) If individual wires, rather than cable, are used in systems greater than 50 volts, the wire... current carrying capacity for the circuit in which they are used; (2) Be installed in a manner to avoid or...

46 CFR 120.340 - Cable and wiring requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... chafing and other damage. The use of plastic tie wraps must be limited to bundling or retention of... wires, rather than cables, are used in systems greater than 50 volts, the wire must be in conduit. (b... for the circuit in which they are used; (2) Be installed in a manner to avoid or reduce interference...

Wire-Guide Manipulator For Automated Welding

NASA Technical Reports Server (NTRS)

Morris, Tim; White, Kevin; Gordon, Steve; Emerich, Dave; Richardson, Dave; Faulkner, Mike; Stafford, Dave; Mccutcheon, Kim; Neal, Ken; Milly, Pete

1994-01-01

Compact motor drive positions guide for welding filler wire. Drive part of automated wire feeder in partly or fully automated welding system. Drive unit contains three parallel subunits. Rotations of lead screws in three subunits coordinated to obtain desired motions in three degrees of freedom. Suitable for both variable-polarity plasma arc welding and gas/tungsten arc welding.

Effects of Ionizing Radiation and Restraint Stress on Activity, Avoidance Conditioning, and Stomach Ulcers in Albino Rats.

DTIC Science & Technology

1984-03-01

surrounded the rat. The ends of the screen wire tube were twisted and secured with galvanized wire. Care was taken to wrap the screen wire tight so that...function. In N. R. DiLuzio and R. Paoletti (eds.). The reticuloendothelial system and atherosclerosis : Advances in experimental medicine and biology, pp

75 FR 70150 - Airworthiness Directives; McDonnell Douglas Corporation Model MD-11 and MD-11F Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-17

... installation of hardware. Boeing stated that the original NPRM implies that only wiring changes would be required; installation of brackets and supporting hardware, however, are required in addition to the wiring... tail tank fuel system, a wiring change, and corrective actions if necessary. That NPRM was prompted by...

46 CFR 111.95-7 - Wiring of boat winch components.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Wiring of boat winch components. 111.95-7 Section 111.95... SYSTEMS-GENERAL REQUIREMENTS Electric Power-Operated Boat Winches § 111.95-7 Wiring of boat winch... electric installation from all sources of potential. The switch must be in series with and on the supply...

Micromagnetic simulations of anisotropies in coupled and uncoupled ferromagnetic nanowire systems.

PubMed

Blachowicz, T; Ehrmann, A

2013-01-01

The influence of a variation of spatial relative orientations onto the coupling dynamics and subsequent magnetic anisotropies was modeled in ferromagnetic nanowires. The wires were analyzed in the most elementary configurations, thus, arranged in pairs perpendicular to each other, leading to one-dimensional (linear) and zero-dimensional (point-like) coupling. Different distances within each elementary pair of wires and between the pairs give rise to varying interactions between parallel and perpendicular wires, respectively. Simulated coercivities show an exchange of easy and hard axes for systems with different couplings. Additionally, two of the systems exhibit a unique switching behavior which can be utilized for developing new functionalities.

Risk management in fly-by-wire systems

NASA Technical Reports Server (NTRS)

Knoll, Karyn T.

1993-01-01

A general description of various types of fly-by-wire systems is provided. The risks inherent in digital flight control systems, like those used in the Space Shuttle, are identified. The results of a literature survey examining risk management methods in use throughout the aerospace industry are presented. The applicability of these methods to the Space Shuttle program is discussed.

14 CFR 25.1717 - Circuit protective devices: EWIS.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Electrical Wiring Interconnection Systems (EWIS) § 25.1717 Circuit protective devices: EWIS. Electrical wires and cables must be designed and...

Breakdown dynamics of electrically exploding thin metal wires in vacuum

NASA Astrophysics Data System (ADS)

Sarkisov, G. S.; Caplinger, J.; Parada, F.; Sotnikov, V. I.

2016-10-01

Using a two-frame intensified charge coupled device (iCCD) imaging system with a 2 ns exposure time, we observed the dynamics of voltage breakdown and corona generation in experiments of fast ns-time exploding fine Ni and stainless-steel (SS) wires in a vacuum. These experiments show that corona generation along the wire surface is subjected to temporal-spatial inhomogeneity. For both metal wires, we observed an initial generation of a bright cathode spot before the ionization of the entire wire length. This cathode spot does not expand with time. For 25.4 μm diameter Ni and SS wire explosions with positive polarity, breakdown starts from the ground anode and propagates to the high voltage cathode with speeds approaching 3500 km/s or approximately one percent of light speed.

Ultrasonic Device for Assessing the Quality of a Wire Crimp

NASA Technical Reports Server (NTRS)

Yost, William T. (Inventor); Perey, Daniel F. (Inventor); Cramer, Karl E. (Inventor)

2015-01-01

A system for determining the quality of an electrical wire crimp between a wire and ferrule includes an ultrasonically equipped crimp tool (UECT) configured to transmit an ultrasonic acoustic wave through a wire and ferrule, and a signal processor in communication with the UECT. The signal processor includes a signal transmitting module configured to transmit the ultrasonic acoustic wave via an ultrasonic transducer, signal receiving module configured to receive the ultrasonic acoustic wave after it passes through the wire and ferrule, and a signal analysis module configured to identify signal differences between the ultrasonic waves. The signal analysis module is then configured to compare the signal differences attributable to the wire crimp to a baseline, and to provide an output signal if the signal differences deviate from the baseline.

XV-15 Tilt Rotor fly-by-wire collective control demonstrator development specifications

NASA Technical Reports Server (NTRS)

Meuleners, R. J.

1981-01-01

A fly by wire system in the collective control system for XV-15 Tilt Rotor Research Aircraft was evaluated. The collective control system was selected because it requires a system tracking accuracy between right and left rotors of approximately 0.1%. The performance characteristics of the collectors axel provide typical axis control response data. The demonstrator is bread boarded as a dual system instead of the triplex system.

Computers Take Flight: A History of NASA's Pioneering Digital Fly-By-Wire Project

NASA Technical Reports Server (NTRS)

Tomayko, James E.

2000-01-01

An overview of the NASA F-8 Fly-by Wire project is presented. The project made two significant contributions to the new technology: (1) a solid design base of techniques that work and those that do not, and (2) credible evidence of good flying qualities and the ability of such a system to tolerate real faults and to continue operation without degradation. In 1972 the F-8C aircraft used in the program became he first digital fly-by-wire aircraft to operate without a mechanical backup system.

Attachment of lead wires to thin film thermocouples mounted on high temperature materials using the parallel gap welding process

NASA Technical Reports Server (NTRS)

Holanda, Raymond; Kim, Walter S.; Pencil, Eric; Groth, Mary; Danzey, Gerald A.

1990-01-01

Parallel gap resistance welding was used to attach lead wires to sputtered thin film sensors. Ranges of optimum welding parameters to produce an acceptable weld were determined. The thin film sensors were Pt13Rh/Pt thermocouples; they were mounted on substrates of MCrAlY-coated superalloys, aluminum oxide, silicon carbide and silicon nitride. The entire sensor system is designed to be used on aircraft engine parts. These sensor systems, including the thin-film-to-lead-wire connectors, were tested to 1000 C.

Hy-wire measurements of atmospheric potential

NASA Astrophysics Data System (ADS)

Holzworth, Robert H.

1984-02-01

A method of directly measuring the electric potential drop across the lowest portion of the atmosphere by using an apparatus called Hy-wire is described. This tethered balloon-borne system has been operated extensively at altitudes near 0.62 km at which voltages over 150 k V were measured with a high impedance device. Also described are measurements of system parameters such as system capacitance (5.6 pf/m), impedance (1010Ω), and response time (tens of seconds). Hy-wire measurements from an around the-clock experiment at Wallops Island, Va., having a characteristic repetitive diurnal pattern of variability exceeding 40% of the mean, are presented. This diurnal pattern is discussed in terms of both local and global current sources. A demonstration using Hy-wire as a lightning channel model is also presented. These experiments have so far been conducted at mid-latitudes but can also be flown from other locations in an effort to determine whether the lowest atmospheric electric circuit is affected by high altitude and possibly global current systems, and if so how much. The data presented in this paper are not definitive about the source of potential variations. The data are, however, representative of the new Hy-wire technique and demonstrative of the potential usefulness of this technique.

NASA/BAE SYSTEMS SpaceWire Effort

NASA Technical Reports Server (NTRS)

Rakow, Glenn Parker; Schnurr, Richard G.; Kapcio, Paul

2003-01-01

This paper discusses the state of the NASA and BAE SYSTEMS developments of SpaceWire. NASA has developed intellectual property that implements SpaceWire in Register Transfer Level (RTL) VHDL for a SpaceWire link and router. This design has been extensively verified using directed tests from the SpaceWire Standard and design specification, as well as being randomly tested to flush out hard to find bugs in the code. The high level features of the design will be discussed, including the support for multiple time code masters, which will be useful for the James Webb Space Telescope electrical architecture. This design is now ready to be targeted to FPGA's and ASICs. Target utilization and performance information will be presented for Spaceflight worthy FPGA's and a discussion of the ASIC implementations will be addressed. In particular, the BAE SYSTEMS ASIC will be highlighted which will be implemented on their .25micron rad-hard line. The chip will implement a 4-port router with the ability to tie chips together to make larger routers without external glue logic. This part will have integrated LVDS drivers/receivers, include a PLL and include skew control logic. It will be targeted to run at greater than 300 MHz and include the implementation for the proposed SpaceWire transport layer. The need to provide a reliable transport mechanism for SpaceWire has been identified by both NASA And ESA, who are attempting to define a transport layer standard that utilizes a low overhead, low latency connection oriented approach that works end-to-end. This layer needs to be implemented in hardware to prevent bottlenecks.

The biomechanical analysis of sublaminar wires and cables using luque segmental spinal instrumentation.

PubMed

Parsons, J R; Chokshi, B V; Lee, C K; Gundlapalli, R V; Stamer, D

1997-02-01

Data was gathered from biomechanical testing of 10 thoracic human cadaveric spines. Spines were tested intact and with a Luque rectangle fixed with wire or cable. To compare the rigidity of fixation and intraspinal penetration of sublaminar monofilament wire and multistrand cable under identical conditions using human cadaveric spines. Reports of neurologic and mechanical complications associated with sublaminar wiring techniques have led to the recent development of more flexible multistrand cable systems. The relative performance of flexible cable versus monofilament wire has not been explored fully in a controlled mechanical environment. A servohydraulic mechanical testing machine was used to measure the static mechanical stiffness of sublaminar wire or cable fixation in conjunction with a Luque rectangle for thoracic human cadaveric spine segments in flexion-extension and torsion modes. Cyclic testing was performed in the flexion-extension mode. Intraspinal penetration of wires and cables was measured. Spine fixation with sublaminar wire and cable resulted in constructs of equal stiffness in flexion-extension and torsion modes. Cyclic testing also indicated similar fatigue profiles for wire- and cable-instrumented spines. Wire and cable fixed spines displayed greater stiffness than the intact spines. Cable encroachment of the spinal canal was less than that seen with wire. Sublaminar multistrand cable may be a rational alternative to monofilament wire in segmental spinal instrumentation because it provides less encroachment into the spinal canal. Further, cadaveric spines instrumented with wire and cable display equivalent mechanical behavior, statically and under cyclic loading. The potential advantages of cable, however, must be balanced against a substantial increase in cost relative to wire.

Heat Transfer Analysis in Wire Bundles for Aerospace Vehicles

NASA Technical Reports Server (NTRS)

Rickman, S. L.; Iamello, C. J.

2016-01-01

Design of wiring for aerospace vehicles relies on an understanding of "ampacity" which refers to the current carrying capacity of wires, either, individually or in wire bundles. Designers rely on standards to derate allowable current flow to prevent exceedance of wire temperature limits due to resistive heat dissipation within the wires or wire bundles. These standards often add considerable margin and are based on empirical data. Commercial providers are taking an aggressive approach to wire sizing which challenges the conventional wisdom of the established standards. Thermal modelling of wire bundles may offer significant mass reduction in a system if the technique can be generalized to produce reliable temperature predictions for arbitrary bundle configurations. Thermal analysis has been applied to the problem of wire bundles wherein any or all of the wires within the bundle may carry current. Wire bundles present analytical challenges because the heat transfer path from conductors internal to the bundle is tortuous, relying on internal radiation and thermal interface conductance to move the heat from within the bundle to the external jacket where it can be carried away by convective and radiative heat transfer. The problem is further complicated by the dependence of wire electrical resistivity on temperature. Reduced heat transfer out of the bundle leads to higher conductor temperatures and, hence, increased resistive heat dissipation. Development of a generalized wire bundle thermal model is presented and compared with test data. The steady state heat balance for a single wire is derived and extended to the bundle configuration. The generalized model includes the effects of temperature varying resistance, internal radiation and thermal interface conductance, external radiation and temperature varying convective relief from the free surface. The sensitivity of the response to uncertainties in key model parameters is explored using Monte Carlo analysis.

A Mechanical Coil Insertion System for Endovascular Coil Embolization of Intracranial Aneurysms

PubMed Central

Haraguchi, K.; Miyachi, S.; Matsubara, N.; Nagano, Y.; Yamada, H.; Marui, N.; Sano, A.; Fujimoto, H.; Izumi, T.; Yamanouchi, T.; Asai, T.; Wakabayashi, T.

2013-01-01

Summary Like other fields of medicine, robotics and mechanization might be introduced into endovascular coil embolization of intracranial aneurysms for effective treatment. We have already reported that coil insertion force could be smaller and more stable when the coil delivery wire is driven mechanically at a constant speed. Another background is the difficulty in synchronizing operators' minds and hands when two operators control the microcatheter and the coil respectively. We have therefore developed a mechanical coil insertion system enabling a single operator to insert coils at a fixed speed while controlling the microcatheter. Using our new system, the operator manipulated the microcatheter with both hands and drove the coil using foot switches simultaneously. A delivery wire force sensor previously reported was used concurrently, allowing the operator to detect excessive stress on the wire. In vitro coil embolization was performed using three methods: simple mechanical advance of the coil; simple mechanical advance of the coil with microcatheter control; and driving (forward and backward) of the coil using foot switches in addition to microcatheter control. The system worked without any problems, and did not interfere with any procedures. In experimental coil embolization, delivery wire control using the foot switches as well as microcatheter manipulation helped to achieve successful insertion of coils. This system could offer the possibility of developing safer and more efficient coil embolization. Although we aim at total mechanization and automation of procedures in the future, microcatheter manipulation and synchronized delivery wire control are still indispensable using this system. PMID:23693038

Color change in acrylic denture base resin reinforced with wire mesh and glass cloth.

PubMed

Kanie, Takahito; Arikawa, Hiroyuki; Fujii, Koichi; Ban, Seiji

2003-12-01

In this study, the L*a*b* color system as a color system and light transmittance of the denture base resin reinforced with wire mesh and glass cloth were measured, and the color difference (deltaE*ab) was calculated using L*, a* and b* values which were measured both on a white calibration plate and on a null background. The thicknesses of test specimens, which were reinforced with wire mesh and glass cloth 0.5 and 1.0 mm below the surface, were 3 and 5 mm. L*, a* and b* values of wire mesh reinforcing specimens decreased in comparison with the non-reinforcing specimens (p<0.05). L* values of glass cloth-reinforcing specimens increased compared with the non-reinforcing specimens (p<0.05). The glass cloth is an effective reinforcing material and an aesthetically important property of denture base resin, since wire mesh makes the resin appear darker with the background condition greatly altering the color, while glass cloth makes the resin lighter.

Performance of magnetic field‐guided navigation system for interventional neurosurgical and cardiac procedures

PubMed Central

Chu, James C.H.; Hsi, Wen Chien; Hubbard, Lincoln; Zhang, Yunkai; Bernard, Damian; Reeder, Pamela; Lopes, Demetrius

2005-01-01

A hospital‐based magnetic guidance system (MGS) was installed to assist a physician in navigating catheters and guide wires during interventional cardiac and neurosurgical procedures. The objective of this study is to examine the performance of this magnetic field‐guided navigation system. Our results show that the system's radiological imaging components produce images with quality similar to that produced by other modern fluoroscopic devices. The system's magnetic navigation components also deflect the wire and catheter tips toward the intended direction. The physician, however, will have to oversteer the wire or catheter when defining the steering angle during the procedure. The MGS could be clinically useful in device navigation deflection and vessel access. PACS numbers: 07.55.Db, 07.85.‐m PMID:16143799

Towards a Reduced-Wire Interface for CMUT-Based Intravascular Ultrasound Imaging Systems

PubMed Central

Lim, Jaemyung; Tekes, Coskun; Degertekin, F. Levent; Ghovanloo, Maysam

2016-01-01

Having intravascular ultrasound (IVUS) imaging capability on guide wires used in cardiovascular interventions may eliminate the need for separate IVUS catheters and expand the use of IVUS in a larger portion of the vasculature. High frequency capacitive micro machined ultrasonic transducer (CMUT) arrays should be integrated with interface electronics and placed on the guide wire for this purpose. Besides small size, this system-on-a-chip (SoC) front-end should connect to the back-end imaging system with a minimum number of wires to preserve the critical mechanical properties of the guide wire. We present a 40 MHz CMUT array interface SoC, which will eventually use only two wires for power delivery and transmits image data using a combination of analog-to-time conversion (ATC) and an impulse radio ultra-wideband (IR-UWB) wireless link. The proof-of-concept prototype ASIC consumes only 52.8 mW and occupies 4.07 mm2 in a 0.35-μm standard CMOS process. A rectifier and regulator power the rest of the SoC at 3.3 V from a 10 MHz power carrier that is supplied through a 2.4 m micro-coax cable with an overall efficiency of 49.1%. Echo signals from an 8-element CMUT array are amplified by a transimpedance amplifier (TIA) array and down-converted to baseband by quadrature sampling using a 40 MHz clock, derived from the power carrier. The ATC generates pulse-width-modulated (PWM) samples at 2 × 10 MS/s with 6 bit resolution, while the entire system achieved 5.1 ENOB. Preliminary images from the prototype system are presented, and alternative data transmission and possible future directions towards practical implementation are discussed. PMID:27662686

Towards a Reduced-Wire Interface for CMUT-Based Intravascular Ultrasound Imaging Systems.

PubMed

Lim, Jaemyung; Tekes, Coskun; Degertekin, F Levent; Ghovanloo, Maysam

2017-04-01

Having intravascular ultrasound (IVUS) imaging capability on guide wires used in cardiovascular interventions may eliminate the need for separate IVUS catheters and expand the use of IVUS in a larger portion of the vasculature. High frequency capacitive micro machined ultrasonic transducer (CMUT) arrays should be integrated with interface electronics and placed on the guide wire for this purpose. Besides small size, this system-on-a-chip (SoC) front-end should connect to the back-end imaging system with a minimum number of wires to preserve the critical mechanical properties of the guide wire. We present a 40 MHz CMUT array interface SoC, which will eventually use only two wires for power delivery and transmits image data using a combination of analog-to-time conversion (ATC) and an impulse radio ultra-wideband (IR-UWB) wireless link. The proof-of-concept prototype ASIC consumes only 52.8 mW and occupies 4.07 [Formula: see text] in a 0.35- [Formula: see text] standard CMOS process. A rectifier and regulator power the rest of the SoC at 3.3 V from a 10 MHz power carrier that is supplied through a 2.4 m micro-coax cable with an overall efficiency of 49.1%. Echo signals from an 8-element CMUT array are amplified by a transimpedance amplifier (TIA) array and down-converted to baseband by quadrature sampling using a 40 MHz clock, derived from the power carrier. The ATC generates pulse-width-modulated (PWM) samples at 2 × 10 MS/s with 6 bit resolution, while the entire system achieved 5.1 ENOB. Preliminary images from the prototype system are presented, and alternative data transmission and possible future directions towards practical implementation are discussed.

78 FR 22175 - Airworthiness Directives; Airbus Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-15

... loading system (CLS) fail under maximum loads and reports that installation has been applied only on one... wiring, or other equipment located in the forward and aft cargo compartments. This damage could adversely... system, electrical wiring, etc.), and therefore could have an impact on the safety of the flight. EASA AD...

Manipulating flexible parts using a teleoperated system with time delay: An experiment

NASA Technical Reports Server (NTRS)

Kotoku, T.; Takamune, K.; Tanie, K.; Komoriya, K.; Matsuhira, N.; Asakura, M.; Bamba, H.

1994-01-01

This paper reports experiments involving the handling of flexible parts (e.g. wires) when using a teleoperated system with time delay. The task is principally a peg-in-hole task involving the wrapping of a wire around two posts on the task-board. It is difficult to estimate the effects of the flexible parts; therefore, on-line teleoperation is indispensable for this class of unpredictable task. We first propose a teleoperation system based on the predictive image display, then describe an experimental teleoperation testbed with a four second transmission time delay. Finally, we report on wire handling operations that were performed to evaluate the performance of this system. Those experiments will contribute to future advanced experiments for the MITI ETS-7 mission.

Dosimetric investigation of LDR brachytherapy ¹⁹²Ir wires by Monte Carlo and TPS calculations.

PubMed

Bozkurt, Ahmet; Acun, Hediye; Kemikler, Gonul

2013-01-01

The aim of this study was to investigate the dose rate distribution around (192)Ir wires used as radioactive sources in low-dose-rate brachytherapy applications. Monte Carlo modeling of a 0.3-mm diameter source and its surrounding water medium was performed for five different wire lengths (1-5 cm) using the MCNP software package. The computed dose rates per unit of air kerma at distances from 0.1 up to 10 cm away from the source were first verified with literature data sets. Then, the simulation results were compared with the calculations from the XiO CMS commercial treatment planning system. The study results were found to be in concordance with the treatment planning system calculations except for the shorter wires at close distances.

Study of the properties of flux cored wire of Fe-C-Si-Mn-Cr-Mo-Ni-V-Co system for the strengthening of nodes and parts of equipment used in the mineral mining

NASA Astrophysics Data System (ADS)

Gusev, A. I.; Kozyrev, N. A.; Usoltsev, A. A.; Kryukov, R. E.; Osetkovsky, I. V.

2017-09-01

The effect of the introduction of vanadium and cobalt into the charge of the powder surfacing wire of Fe-C-Si-Mn-Cr-Mo-Ni system is studied. In the laboratory conditions, the samples of flux cored wires were produced. The surfacing made by the prepared wire was produced under the flux AN-26C, on the plates of steel St3 in 6 layers with the help of ASAW-1250 welding tractor. Reduction of carbon content in the deposited layer to 0.19-0.2% with simultaneous change in the content of chromium, nickel, molybdenum and other elements present in it contributes to the enlargement of the martensite needles and the increase in the size of the former austenite grain. The obtained dependences of hardness of the deposited layer and its wear resistance on the mass fraction of elements, included in the composition of powder wires of the proposed system, can be used to predict the hardness of the welded layer and its wear resistance under different operating conditions for mining equipment and coal mining equipment.

Controlling an indirect hot water heater

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

Capano, J.

The procedure for servicing a Dunkirk Empire indirect water heater is presented. In this particular case the serviceman found that a wire was loose on the aquastat on the tank. The serviceman checked the wire and the past and tightened the connection. This took care of the problem. A wiring diagram is presented for the home heating system and the hot water heater.

Real-time logic modelling on SpaceWire

NASA Astrophysics Data System (ADS)

Zhou, Qiang; Ma, Yunpeng; Fei, Haidong; Wang, Xingyou

2017-04-01

A SpaceWire is a standard for on-board satellite networks as the basis for future data-handling architectures. However, it cannot meet the deterministic requirement for safety/time critical application in spacecraft, where the delay of real-time (RT) message streams must be guaranteed. Therefore, SpaceWire-D is developed that provides deterministic delivery over a SpaceWire network. Formal analysis and verification of real-time systems is critical to their development and safe implementation, and is a prerequisite for obtaining their safety certification. Failure to meet specified timing constraints such as deadlines in hard real-time systems may lead to catastrophic results. In this paper, a formal verification method, Real-Time Logic (RTL), has been proposed to specify and verify timing properties of SpaceWire-D network. Based on the principal of SpaceWire-D protocol, we firstly analyze the timing properties of fundamental transactions, such as RMAP WRITE, and RMAP READ. After that, the RMAP WRITE transaction structure is modeled in Real-Time Logic (RTL) and Presburger Arithmetic representations. And then, the associated constraint graph and safety analysis is provided. Finally, it is suggested that RTL method can be useful for the protocol evaluation and provision of recommendation for further protocol evolutions.

75 FR 12464 - Airworthiness Directives; McDonnell Douglas Corporation Model MD-11 and MD-11F Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-16

... would require a one-time inspection to detect damage of the wire assemblies of the tail tank fuel system, a wiring change, and corrective actions if necessary. This proposed AD results from fuel system... existing maintenance practices for fuel tank systems. As a result of those findings, we issued a regulation...

OBSANP Data Acquisition System: Operator’s Manual and System Overview

DTIC Science & Technology

2013-10-01

SN  11  –  updated  TCR  from  Arlie  Farlie  during  expedition   52   Figure  28.     Octopus  Wiring  Diagram...Operator’s Manual and System Overview Page 53 of 54 Figure 28. Octopus Wiring Diagram / Neil McPhee (WHOI) WHOI-2013-06 OBSANP Data Acquisition

Development of Active Catheter,Active Guide Wire and Micro Sensor Systems

PubMed Central

Haga, Y.; Mineta, T.; Totsu, K.; Makishi, W.; Esashi, M.

2001-01-01

Summary Active catheters and active guide wires which move like a snake have been developed for catheter-based minimally invasive diagnosis and therapy. Communication and control IC chips in the active catheter reduce the number of lead wires for control. The active catheter can be not only bent but also torsioned and extended. An ultra minature fiber-optic pressure sensor; a forward-looking ultrasonic probe and a magnetic position and orientation sensor have been developed for catheters and guide wires. These moving mechanisms and several sensors which are fitted near the tip of the catheter and the guide wire will provide detailed information near the tip and enable delicate and effective catheter intervention. PMID:20663389

Condenser assembly system for an appliance

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

Litch, Andrew David

2017-10-17

An appliance includes a compact condenser assembly formed with at least two separately and independently produced wire on tube condensers. Each of the at least two wire on tube condensers has a condenser inlet and a condenser outlet. The at least two wire on tube condensers are at least substantially locked and positioned in a matingly engaged configuration forming a compact condenser assembly. The at least two wire on tube condensers are configured to be operationally connected in at least one of a parallel configuration, a series configuration, a selectable configuration, and a bypass configuration.

Effect of wire size on maxillary arch force/couple systems for a simulated high canine malocclusion.

PubMed

Major, Paul W; Toogood, Roger W; Badawi, Hisham M; Carey, Jason P; Seru, Surbhi

2014-12-01

To better understand the effects of copper nickel titanium (CuNiTi) archwire size on bracket-archwire mechanics through the analysis of force/couple distributions along the maxillary arch. The hypothesis is that wire size is linearly related to the forces and moments produced along the arch. An Orthodontic Simulator was utilized to study a simplified high canine malocclusion. Force/couple distributions produced by passive and elastic ligation using two wire sizes (Damon 0.014 and 0.018 inch) measured with a sample size of 144. The distribution and variation in force/couple loading around the arch is a complicated function of wire size. The use of a thicker wire increases the force/couple magnitudes regardless of ligation method. Owing to the non-linear material behaviour of CuNiTi, this increase is less than would occur based on linear theory as would apply for stainless steel wires. The results demonstrate that an increase in wire size does not result in a proportional increase of applied force/moment. This discrepancy is explained in terms of the non-linear properties of CuNiTi wires. This non-proportional force response in relation to increased wire size warrants careful consideration when selecting wires in a clinical setting. © 2014 British Orthodontic Society.

The effect of electrostatic and gravity force on offset wire inside tube

NASA Astrophysics Data System (ADS)

Oh, S. H.; Hazineh, D.; Wang, C.

2018-04-01

In a straw-tube detector, a wire that is offset with respect to the tube axis experiences a Coulomb force when high voltage is applied between the anode wire and the tube. This force results in a shifting of the wire and straw, in addition to the gravitational sag, and is a function of the tube and wire radius, initial offset, high voltage, tension and length. The presence of such effects is well known, but the precise magnitude of the shift for the anode wires under conditions of detector operation have not been previously documented with measurable confidence. In this work, we provide the first systematic measurements for the wire shift in straw-tube detectors due to gravity and the electrostatic force using an x-ray scanner developed for the Mu2e experiment. The data are compared to the solutions of the differential equations governing the system, and we find a good match between the two. The solutions can predict the final wire and straw positions from the initial positions measured without the high voltage, and the final wire and straw positions can then be used as an input to the track reconstruction software to improve the track position resolution.

Wiring Damage Analyses for STS OV-103

NASA Technical Reports Server (NTRS)

Thomas, Walter, III

2006-01-01

This study investigated the Shuttle Program s belief that Space Transportation System (STS) wiring damage occurrences are random, that is, a constant occurrence rate. Using Problem Reporting and Corrective Action (PRACA)-derived data for STS Space Shuttle OV-103, wiring damage was observed to increase over the vehicle s life. Causal factors could include wiring physical deterioration, maintenance and inspection induced damage, and inspection process changes resulting in more damage events being reported. Induced damage effects cannot be resolved with existent data. Growth analysis (using Crow-AMSAA, or CA) resolved maintenance/inspection effects (e.g., heightened awareness) on all wire damages and indicated an overall increase since Challenger Return-to-Flight (RTF). An increasing failure or occurrence rate per flight cycle was seen for each wire damage mode; these (individual) rates were not affected by inspection process effects, within statistical error.

Ultrasonics Equipped Crimp Tool: A New Technology for Aircraft Wiring Safety

NASA Technical Reports Server (NTRS)

Yost, William T.; Perey, Daniel F.; Cramer, Elliott

2006-01-01

We report on the development of a new measurement technique to quantitatively assess the condition of wire crimp connections. This ultrasonic (UT) method transmits high frequency sound waves through the joint under inspection. The wire-crimp region filters and scatters the ultrasonic energy as it passes through the crimp and wire. The resulting output (both time and frequency domains) provides a quantitative measure of the joint quality that is independent and unaffected by current. Crimps of poor mechanical and electrical quality will result in low temporal output and will distort the spectrum into unique and predictable patterns, depending on crimp "quality". This inexpensive, real-time measurement system can provide certification of crimps as they are made and recertification of existing wire crimps currently in service. The measurements for re-certification do not require that the wire be disconnected from its circuit. No other technology exists to measure in-situ the condition of wire joints (no electrical currents through the crimp are used in this analytical technique). We discuss the signals obtained from this instrument, and correlate these signals with destructive wire pull tests.

Mechanization of and experience with a triplex fly-by-wire backup control system

NASA Technical Reports Server (NTRS)

Lock, W. P.; Petersen, W. R.; Whitman, G. B.

1975-01-01

A redundant three-axis analog control system was designed and developed to back up a digital fly-by-wire control system for an F-8C airplane. Forty-two flights, involving 58 hours of flight time, were flown by six pilots. The mechanization and operational experience with the backup control system, the problems involved in synchronizing it with the primary system, and the reliability of the system are discussed. The backup control system was dissimilar to the primary system, and it provided satisfactory handling through the flight envelope evaluated. Limited flight tests of a variety of control tasks showed that control was also satisfactory when the backup control system was controlled by a minimum-displacement (force) side stick. The operational reliability of the F-8 digital fly-by-wire control system was satisfactory, with no unintentional downmodes to the backup control system in flight. The ground and flight reliability of the system's components is discussed.

Mechanical properties of NiTi and CuNiTi wires used in orthodontic treatment. Part 2: Microscopic surface appraisal and metallurgical characteristics

PubMed Central

Gravina, Marco Abdo; Canavarro, Cristiane; Elias, Carlos Nelson; Chaves, Maria das Graças Afonso Miranda; Brunharo, Ione Helena Vieira Portella; Quintão, Cátia Cardoso Abdo

2014-01-01

Objective This research aimed at comparing the qualitative chemical compositions and the surface morphology of fracture regions of eight types of Nickel (Ni) Titanium (Ti) conventional wires, superelastic and heat-activated (GAC, TP, Ormco, Masel, Morelli and Unitek), to the wires with addition of copper (CuNiTi 27ºC and 35ºC, Ormco) after traction test. Methods The analyses were performed in a scanning electronic microscope (JEOL, model JSM-5800 LV) with EDS system of microanalysis (energy dispersive spectroscopy). Results The results showed that NiTi wires presented Ni and Ti as the main elements of the alloy with minimum differences in their composition. The CuNiTi wires, however, presented Ni and Ti with a significant percentage of copper (Cu). As for surface morphology, the wires that presented the lowest wire-surface roughness were the superelastic ones by Masel and Morelli, while those that presented the greatest wire-surface roughness were the CuNiTi 27ºC and 35ºC ones by Ormco, due to presence of microcavity formed as a result of pulling out some particles, possibly of NiTi.4 The fracture surfaces presented characteristics of ductile fracture, with presence of microcavities. The superelastic wires by GAC and the CuNiTi 27ºC and the heat-activated ones by Unitek presented the smallest microcavities and the lowest wire-surface roughness with regard to fracture, while the CuNiTi 35ºC wires presented inadequate wire-surface roughness in the fracture region. Conclusion CuNiTi 35ºC wires did not present better morphologic characteristics in comparison to the other wires with regard to surfaces and fracture region. PMID:24713562

The Use of a Steering Shaping Function to Improve Human Performance in By-Wire Vehicles

DTIC Science & Technology

2008-03-01

nontrivial ways. Included in the problems induced by the staffing of automated systems are biomechanical (Sirouspour & Salcudean, 2003; Sövényi...device (e.g., brake pedal ) and the actuators of the system (e.g., calipers). In this report, we are specifically interested in steer-by-wire subsystems

A gating grid driver for time projection chambers

NASA Astrophysics Data System (ADS)

Tangwancharoen, S.; Lynch, W. G.; Barney, J.; Estee, J.; Shane, R.; Tsang, M. B.; Zhang, Y.; Isobe, T.; Kurata-Nishimura, M.; Murakami, T.; Xiao, Z. G.; Zhang, Y. F.; SπRIT Collaboration

2017-05-01

A simple but novel driver system has been developed to operate the wire gating grid of a Time Projection Chamber (TPC). This system connects the wires of the gating grid to its driver via low impedance transmission lines. When the gating grid is open, all wires have the same voltage allowing drift electrons, produced by the ionization of the detector gas molecules, to pass through to the anode wires. When the grid is closed, the wires have alternating higher and lower voltages causing the drift electrons to terminate at the more positive wires. Rapid opening of the gating grid with low pickup noise is achieved by quickly shorting the positive and negative wires to attain the average bias potential with N-type and P-type MOSFET switches. The circuit analysis and simulation software SPICE shows that the driver restores the gating grid voltage to 90% of the opening voltage in less than 0.20 μs, for small values of the termination resistors. When tested in the experimental environment of a time projection chamber larger termination resistors were chosen so that the driver opens the gating grid in 0.35 μs. In each case, opening time is basically characterized by the RC constant given by the resistance of the switches and terminating resistors and the capacitance of the gating grid and its transmission line. By adding a second pair of N-type and P-type MOSFET switches, the gating grid is closed by restoring 99% of the original charges to the wires within 3 μs.

Differences in the force system delivered by different beta-titanium wires in elaborate designs.

PubMed

Martins, Renato Parsekian; Caldas, Sergei Godeiro Fernandes Rabelo; Ribeiro, Alexandre Antonio; Vaz, Luís Geraldo; Shimizu, Roberto Hideo; Martins, Lídia Parsekian

2015-01-01

Evaluation of the force system produced by four brands of b-Ti wires bent into an elaborate design. A total of 40 T-loop springs (TLS) hand-bent from 0.017 x 0.025-in b-Ti were randomly divided into four groups according to wire brand: TMATM(G1), BETA FLEXYTM (G2), BETA III WIRETM (G3) and BETA CNATM (G4). Forces and moments were recorded by a moment transducer, coupled to a digital extensometer indicator adapted to a testing machine, every 0.5 mm of deactivation from 5 mm of the initial activation. The moment-to-force (MF) ratio, the overlapping of the vertical extensions of the TLSs and the load-deflection (LD) ratio were also calculated. To complement the results, the Young's module (YM) of each wire was determined by the slope of the load-deflection graph of a tensile test. The surface chemical composition was also evaluated by an energy dispersive X-ray fluorescence spectrometer. All groups, except for G2, produced similar force levels initially. G3 produced the highest LD rates and G1 and G4 had similar amounts of overlap of the vertical extensions of the TLSs in "neutral position". G1 and G3 delivered the highest levels of moments, and G2 and G3 produced the highest MF ratios. b-Ti wires from G3 produced the highest YM and all groups showed similar composition, except for G2. The four beta-titanium wires analyzed produced different force systems when used in a more elaborate design due to the fact that each wire responds differently to bends.

New devices for flow measurements: Hot film and burial wire sensors, infrared imagery, liquid crystal, and piezo-electric model

NASA Technical Reports Server (NTRS)

Mcree, Griffith J., Jr.; Roberts, A. Sidney, Jr.

1991-01-01

An experimental program aimed at identifying areas in low speed aerodynamic research where infrared imaging systems can make significant contributions is discussed. Implementing a new technique, a long electrically heated wire was placed across a laminar flow. By measuring the temperature distribution along the wire with the IR imaging camera, the flow behavior was identified.

Orbiter CCTV video signal noise analysis

NASA Technical Reports Server (NTRS)

Lawton, R. M.; Blanke, L. R.; Pannett, R. F.

1977-01-01

The amount of steady state and transient noise which will couple to orbiter CCTV video signal wiring is predicted. The primary emphasis is on the interim system, however, some predictions are made concerning the operational system wiring in the cabin area. Noise sources considered are RF fields from on board transmitters, precipitation static, induced lightning currents, and induced noise from adjacent wiring. The most significant source is noise coupled to video circuits from associated circuits in common connectors. Video signal crosstalk is the primary cause of steady state interference, and mechanically switched control functions cause the largest induced transients.

Simultaneous distribution of AC and DC power

DOEpatents

Polese, Luigi Gentile

2015-09-15

A system and method for the transport and distribution of both AC (alternating current) power and DC (direct current) power over wiring infrastructure normally used for distributing AC power only, for example, residential and/or commercial buildings' electrical wires is disclosed and taught. The system and method permits the combining of AC and DC power sources and the simultaneous distribution of the resulting power over the same wiring. At the utilization site a complementary device permits the separation of the DC power from the AC power and their reconstruction, for use in conventional AC-only and DC-only devices.

Comparison of the efficacy of tooth alignment among lingual and labial brackets: an in vitro study.

PubMed

Alobeid, Ahmad; El-Bialy, Tarek; Reimann, Susanne; Keilig, Ludger; Cornelius, Dirk; Jäger, Andreas; Bourauel, Christoph

2018-03-13

The aim of this study was to evaluate the efficacy of tooth alignment with conventional and self-ligating labial and lingual orthodontic bracket systems. We tested labial brackets (0.022″ slot size) and lingual brackets (0.018″ slot size). The labial brackets were: (i) regular twin brackets (GAC-Twin [Dentsply]), (ii) passive self-ligating brackets including (Damon-Q® [ORMCO]; Ortho classic H4™ [Orthoclassic]; FLI®SL [RMO]), and (iii) active self-ligating brackets (GAC In-Ovation®C [DENTSPLY] and SPEED™[Strite]). The lingual brackets included (i) twin bracket systems (Incognito [3M] and Joy™ [Adenta]), (ii) passive self-ligating bracket system (GAC In-Ovation®LM™ [Dentsply]), and (iii) active self-ligating bracket system (Evolution SLT [Adenta]). The tested wires were Thermalloy-NiTi 0.013″ and 0.014″ (RMO). The archwires were tied to the regular twin brackets with stainless steel ligatures 0.010″ (RMO). The malocclusion simulated a displaced maxillary central incisor in the x-axis (2 mm gingivally) and in the z-axis (2 mm labially). The results showed that lingual brackets are less efficient in aligning teeth when compared with labial brackets in general. The vertical correction achieved by labial bracket systems ranged from 72 to 95 per cent with 13″ Thermalloy wires and from 70 to 87 per cent with 14″ Thermalloy wires. In contrast, the achieved corrections by lingual brackets with 13″ Thermalloy wires ranged between 25-44 per cent and 29-52 per cent for the 14" Thermalloy wires. The anteroposterior correction achieved by labial brackets ranged between 83 and 138 per cent for the 13″ Thermalloy and between 82 and 129 per cent for the 14″ Thermalloy wires. On the other hand, lingual brackets corrections ranged between 12 and 40 per cent for the 13″ Thermalloy wires and between 30 and 45 per cent for the 14″ Thermalloy wires. This is a lab-based study with different labial and lingual bracket slot sizes (however they are the commonly used ones in clinical orthodontics) and study did not consider saliva, periodontal ligament, mastication and other oral functions. The effectiveness of lingual brackets in correcting vertical and anteroposterior displacement achieved during the initial alignment phase of orthodontic treatment is lower than that of the effectiveness of labial brackets.

Fixation systems of greater trochanteric osteotomies: biomechanical and clinical outcomes.

PubMed

Jarit, Gregg J; Sathappan, Sathappan S; Panchal, Anand; Strauss, Eric; Di Cesare, Paul E

2007-10-01

The development of cerclage systems for fixation of greater trochanteric osteotomies has progressed from monofilament wires to multifilament cables to cable grip and cable plate systems. Cerclage wires and cables have various clinical indications, including fixation for fractures and for trochanteric osteotomy in hip arthroplasty. To achieve stable fixation and eventual union of the trochanteric osteotomy, the implant must counteract the destabilizing forces associated with pull of the peritrochanteric musculature. The material properties of cables and cable grip systems are superior to those of monofilament wires; however, potential complications with the use of cables include debris generation and third-body polyethylene wear. Nevertheless, the cable grip system provides the strongest fixation and results in lower rates of nonunion and trochanteric migration. Cable plate constructs show promise but require further clinical studies to validate their efficacy and safety.

Practical aspects of instrumentation system installation, volume 13

NASA Technical Reports Server (NTRS)

Borek, R. W.; Pool, A. (Editor); Sanderson, K. C. (Editor)

1981-01-01

A review of factors influencing installation of aircraft flight test instrumentation is presented. Requirements, including such factors as environment, reliability, maintainability, and system safety are discussed. The assessment of the mission profile is followed by an overview of electrical and mechanical installation factors with emphasis on shock/vibration isolation systems and standardization of the electric wiring installation, two factors often overlooked by instrumentation engineers. A discussion of installation hardware reviews the performance capabilities of wiring, connectors, fuses and circuit breakers, and a guide to proper selections is provided. The discussion of the installation is primarily concerned with the electrical wire routing, shield terminations and grounding. Also inclued are some examples of installation mistakes that could affect system accuracy. System verification procedures and special considerations such as sneak circuits, pyrotechnics, aircraft antenna patterns, and lightning strikes are discussed.

'There were more wires than him': the potential for wireless patient monitoring in neonatal intensive care.

PubMed

Bonner, Oliver; Beardsall, Kathryn; Crilly, Nathan; Lasenby, Joan

2017-02-01

The neonatal intensive care unit (NICU) can be one of the most stressful hospital environments. Alongside providing intensive clinical care, it is important that parents have the opportunity for regular physical contact with their babies because the neonatal period is critical for parent-child bonding. At present, monitoring technology in the NICU requires multiple wired sensors to track each baby's vital signs. This study describes the experiences that parents and nurses have with the current monitoring methods, and reports on their responses to the concept of a wireless monitoring system. Semistructured interviews were conducted with six parents, each of whom had babies on the unit, and seven nurses who cared for those babies. The interviews initially focused on the participants' experiences of the current wired system and then on their responses to the concept of a wireless system. The transcripts were analysed using a general inductive approach to identify relevant themes. Participants reported on physical and psychological barriers to parental care, the ways in which the current system obstructed the efficient delivery of clinical care and the perceived benefits and risks of a wireless system. The parents and nurses identified that the wires impeded baby-parent bonding; physically and psychologically. While a wireless system was viewed as potentially enabling greater interaction, staff and parents highlighted potential concerns, including the size, weight and battery life of any new device. The many wires required to safely monitor babies within the NICU creates a negative environment for parents at a critical developmental period, in terms of physical and psychological interactions. Nurses also experience challenges with the existing system, which could negatively impact the clinical care delivery. Developing a wireless system could overcome these barriers, but there remain challenges in designing a device suitable for this unique environment.

Advanced Lighting Controls for Reducing Energy use and Cost in DoD Installations

DTIC Science & Technology

2013-05-01

OccuSwitch Wireless is a room-based lighting control system employing dimmable light sources, occupancy and daylight sensors , wireless interconnection...combination of wireless and wired control solution for building-wide networked system that maximizes the use of daylight while improving visual...architecture of Hybrid ILDC. Architecture: The system features wireless connectivity among sensors and actuators within a zone and exploits wired

[Three-dimensional finite element analysis of maxillary anterior teeth retraction force system in light wire technique].

PubMed

Zhang, Xiangfeng; Wang, Chao; Xia, Xi; Deng, Feng; Zhang, Yi

2015-06-01

This study aims to construct a three-dimensional finite element model of a maxillary anterior teeth retraction force system in light wire technique and to investigate the difference of hydrostatic pressure and initial displacement of upper anterior teeth under different torque values of tip back bend. A geometric three-dimensional model of the maxillary bone, including all the upper teeth, was achieved via CT scan. To construct the force model system, lingual brackets and wire were constructed by using the Solidworks. Brackets software, and wire were assembled to the teeth. ANASYS was used to calculate the hydrostatic pressure and the initial displacement of maxillary anterior teeth under different tip-back bend moments of 15, 30, 45, 60, and 75 Nmm when the class II elastic force was 0.556 N. Hydrostatic pressure was concentrated in the root apices and cervical margin of upper anterior teeth. Distal tipping and relative intrusive displacement were observed. The hydrostatic pressure and initial displacement of upper canine were greater than in the central and lateral incisors. This hydrostatic pressure and initial intrusive displacement increased with an increase in tip-back bend moment. Lingual retraction force system of maxillary anterior teeth in light wire technique can be applied safely and controllably. The type and quantity of teeth movement can be controlled by the alteration of tip-back bend moment.

KSC-08pd0036

NASA Image and Video Library

2008-01-13

KENNEDY SPACE CENTER, FLA. -- This closeup shows the final splicing completed on the wiring between space shuttle Atlantis' external tank and the engine cutoff, or ECO, sensor system before the replacement feed-through connector in the ECO sensor system is installed. Cryogenic shielding is installed around the wiring. The feed-through connector passes the wires from the inside of the tank to the outside. Results of a tanking test on Dec. 18 pointed to an open circuit in the feed-through connector wiring, which is located at the base of the tank. The pins in the replacement connector have been precisely soldered to create a connection that allows sensors inside the tank to send signals to the computers onboard Atlantis. The work is being done on Launch Pad 39A. Space shuttle Atlantis is now targeted for launch on Feb. 7. Photo credit: NASA/George Shelton

Mechanical Backup For Fly-By-Wire Control System

NASA Technical Reports Server (NTRS)

Stewart, Eric C.

1992-01-01

Mechanical device eliminates need for redundant fly-by-wire subsystems. Main components are two linkages. One connected to control column in conventional, reversible control system. Other slides inside first linkage and connected to pilot's control wheel. In addition to aircraft applications, design used in control systems in which computer control desirable but safety backup systems required; for example, in boat rudders, engine controls in boats and automobiles, and controls in construction equipment.

Design of the smart home system based on the optimal routing algorithm and ZigBee network.

PubMed

Jiang, Dengying; Yu, Ling; Wang, Fei; Xie, Xiaoxia; Yu, Yongsheng

2017-01-01

To improve the traditional smart home system, its electric wiring, networking technology, information transmission and facility control are studied. In this paper, we study the electric wiring, networking technology, information transmission and facility control to improve the traditional smart home system. First, ZigBee is used to replace the traditional electric wiring. Second, a network is built to connect lots of wireless sensors and facilities, thanks to the capability of ZigBee self-organized network and Genetic Algorithm-Particle Swarm Optimization Algorithm (GA-PSOA) to search for the optimal route. Finally, when the smart home system is connected to the internet based on the remote server technology, home environment and facilities could be remote real-time controlled. The experiments show that the GA-PSOA reduce the system delay and decrease the energy consumption of the wireless system.

Design of the smart home system based on the optimal routing algorithm and ZigBee network

PubMed Central

Xie, Xiaoxia

2017-01-01

To improve the traditional smart home system, its electric wiring, networking technology, information transmission and facility control are studied. In this paper, we study the electric wiring, networking technology, information transmission and facility control to improve the traditional smart home system. First, ZigBee is used to replace the traditional electric wiring. Second, a network is built to connect lots of wireless sensors and facilities, thanks to the capability of ZigBee self-organized network and Genetic Algorithm-Particle Swarm Optimization Algorithm (GA-PSOA) to search for the optimal route. Finally, when the smart home system is connected to the internet based on the remote server technology, home environment and facilities could be remote real-time controlled. The experiments show that the GA-PSOA reduce the system delay and decrease the energy consumption of the wireless system. PMID:29131868

Miniaturized optoelectronic system for telemetry of in vivo voltammetric signals.

PubMed

De Simoni, M G; De Luigi, A; Imeri, L; Algeri, S

1990-08-01

In vivo voltammetry is an electrochemical technique that uses carbon fiber microelectrodes stereotaxically implanted in brain areas to monitor monoamine metabolism and release continuously, in freely moving animals. Electric wires connect the polarograph to the animal. A wire-less transmission system (optoelectronic transmission, OPT) of voltammetric signals is described here. It uses infrared diffused light, exploiting the diffusion of the transmitted light over walls and ceiling towards a receiver. The transmission system consists of a main unit and a satellite unit (40 x 30 x 5 mm) positioned on the animal's back. Voltammetric recordings obtained by the classical system (with wires) and by OPT are well defined and almost identical in shape. The power supply is provided by two thin lithium batteries (+/- 3V) that can record for up to 20 h. OPT permits detailed behavioral observations since the animal can be left free to move in a spacious environment. Voltammetry using OPT allows simultaneous recording of neuronal firing activity as well as electroencephalographic recordings (EEG) since there is no cross-talk between the circuits used. The results illustrate the reliability and usefulness of this wire-less transmission system for studying relationships between neurochemical, behavioral and electrophysiological activities.

Findings from NASA's 2015-2017 Electric Sail Investigations

NASA Technical Reports Server (NTRS)

Wiegmann, Bruce. M.

2017-01-01

Electric Sail (E-Sail) propulsion systems will enable scientific spacecraft to obtain velocities of up to 10 astronomical units per year without expending any on-board propellant. The E-Sail propulsion is created from the interaction of a spacecraft's positively charged multi-kilometer-length conductor/s with protons that are present in the naturally occurring hypersonic solar wind. The protons are deflected via natural electrostatic repulsion forces from the Debye sheath that is formed around a charged wire in space, and this deflection of protons creates thrust or propulsion in the opposite direction. It is envisioned that this E-Sail propulsion system can provide propulsion throughout the solar system and to the heliosphere and beyond. Consistent with the concept of a "sail," no propellant is needed as electrostatic repulsion interactions between the naturally occurring solar wind protons and a positively charged wire creates the propulsion. The basic principle on which the Electric Sail operates is the exchange of momentum between an "electric sail" and solar wind, which continually flows radially away from the sun at speeds ranging from 300 to 700 kilometers per second. The "sail" consists of an array of long, charged wires which extend radially outward 10 to 30 kilometers from a slowly rotating spacecraft. Momentum is transferred from the solar wind to the array through the deflection of the positively charged solar wind protons by a high voltage potential applied to the wires. The thrust generated by an E-Sail is proportional to the area of the sail, which is given by the product of the total length of the wires and the effective wire diameter. The wire is approximately 0.1 millimeters in diameter. However, the effective diameter is determined by the distance the applied electric potential penetrates into space around the wire (on the order of 10 meters at 1 astronomical unit). As a result, the effective area over which protons are repelled is proportional to the size of the region of electric potential, or the plasma sheath region, surround the wires of the array. A large sheath is, therefore, beneficial to the generation of thrust. However, this benefit must be balanced with the additional fact that electron collection is proportional to sheath size. Electrons collected by the wire array must be injected back into the solar wind in order to maintain the potential on the wires - which requires power. The primary power requirement for E-Sail operation is, therefore, also proportional to sheath size.

Process water reduction in a wire milling operation. 1989 summer intern report

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

Alberg, J.

1989-12-31

Johnson Filtration Systems is a company located in New Brighton, Minnesota which employs 256 people. The focus of the project was to reduce the water usage of the wire milling operation. Water in the milling process is used to clean the wire and cool the mill components. Total annual water usage for this operation is six million gallons. The milling process changes the cross sectional shape of the wire by using flattening hammers and rollers. A synthetic coolant is used to enhance this process and remove heat. The coolant is removed from the wire as it is pulled through amore » squeegee, washed it with water and dried with an air knife.« less

A fluid-mechanical sewing machine

NASA Astrophysics Data System (ADS)

Lister, John; Chiu-Webster, Sunny

2004-11-01

It is a breakfast-table experience that when a viscous fluid thread falls a sufficient height onto a stationary horizontal surface the thread is undergoes a coiling instability. We describe experimental observations of a viscous thread falling onto a steadily moving horizontal belt. Low (or zero) belt speeds produce coiling as expected. High belt speeds produce a steady thread, whose shape is well-predicted by theory for a stretching catenary with surface tension and inertia. Intermediate belt speeds show various modes of oscillation, which produce a variety of `stitching' patterns on the belt. The onset of oscillations is predicted theoretically.

Metallic Glass Wire Based Localization of Kinesin/Microtubule Bio-molecular Motility System

NASA Astrophysics Data System (ADS)

Kim, K.; Sikora, A.; Yaginuma, S.; Nakayama, K. S.; Nakazawa, H.; Umetsu, M.; Hwang, W.; Teizer, W.

2014-03-01

We report electrophoretic accumulation of microtubules along metallic glass (Pd42.5Cu30Ni7.5P20) wires free-standing in solution. Microtubules are dynamic cytoskeletal filaments. Kinesin is a cytoskeletal motor protein. Functions of these bio-molecules are central to various dynamic cellular processes. Functional artificial organization of bio-molecules is a prerequisite for transferring their native functions into device applications. Fluorescence microscopy at the individual-microtubule level reveals microtubules aligning along the wire axis during the electrophoretic migration. Casein-treated electrodes are effective for releasing trapped microtubules upon removal of the external field. Furthermore, we demonstrate gliding motion of microtubules on kinesin-treated metallic glass wires. The reversible manner in the local adsorption of microtubules, the flexibility of wire electrodes, and the compatibility between the wire electrode and the bio-molecules are beneficial for spatio-temporal manipulation of the motility machinery in 3 dimensions.

Magnetization and magnetoresistance of common alloy wires used in cryogenic instrumentation.

PubMed

Abrecht, M; Adare, A; Ekin, J W

2007-04-01

We present magnetization and magnetoresistance data at liquid-helium and liquid-nitrogen temperatures for wire materials commonly used for instrumentation wiring of specimens, sensors, and heaters in cryogenic probes. The magnetic susceptibilities in Systeme International units at 4.2 K were found to be: Manganin 1.25x10(-2), Nichrome 5.6x10(-3), and phosphor bronze -3.3x10(-5), indicating that phosphor bronze is the most suitable for high-field applications. We also show the ferromagnetic hysteresis loop of Constantan wire at liquid-helium temperature. The magnetoresistance of these four wires was relatively small: the changes in resistance at 4 K due to a 10 T transverse magnetic field are -2.56% for Constantan, -2.83% for Manganin, +0.69% for Nichrome, and +4.5% for phosphor bronze, compared to about +188% for a typical copper wire under the same conditions.

Magnetization and magnetoresistance of common alloy wires used in cryogenic instrumentation

NASA Astrophysics Data System (ADS)

Abrecht, M.; Adare, A.; Ekin, J. W.

2007-04-01

We present magnetization and magnetoresistance data at liquid-helium and liquid-nitrogen temperatures for wire materials commonly used for instrumentation wiring of specimens, sensors, and heaters in cryogenic probes. The magnetic susceptibilities in Systeme International units at 4.2 K were found to be: Manganin 1.25×10-2, Nichrome 5.6×10-3, and phosphor bronze -3.3×10-5, indicating that phosphor bronze is the most suitable for high-field applications. We also show the ferromagnetic hysteresis loop of Constantan wire at liquid-helium temperature. The magnetoresistance of these four wires was relatively small: the changes in resistance at 4 K due to a 10 T transverse magnetic field are -2.56% for Constantan, -2.83% for Manganin, +0.69% for Nichrome, and +4.5% for phosphor bronze, compared to about +188% for a typical copper wire under the same conditions.

Torque resistance of different stainless steel wires commonly used for fixed retainers in orthodontics.

PubMed

Arnold, Dario T; Dalstra, Michel; Verna, Carlalberta

2016-06-01

Movements of teeth splinted by fixed retention wires after orthodontic treatment have been observed. The aetiological factors for these movements are unknown. The aim of this in vitro study was to compare the resistance to torque of different stainless steel wires commonly used for fixed retainers in orthodontics. Torquing moments acting on a retainer wire were measured in a mechanical force testing system by applying buccal crown torque to an upper lateral incisor in both a 3-teeth and in a 2-teeth setup. Seven stainless steel wires with different shape, type (plain, braided, coaxial, or chain) and dimensions were selected for this study. For a torquing angle of 16.2° in the 3-teeth setup torsion moments can vary between 390 cNmm and 3299 cNmm depending on the retainer wire. For the 2-teeth setup the torsion moments are much smaller. Exposure to the flame of a butane-gas torch for 10 seconds to anneal the wire reduces the stiffness of the retainer wire. Clinicians must select wires for fixed retainers very carefully since the difference in resistance to torque is large. A high level of torque control can be achieved with a plain 0.016 × 0.016-inch or a braided 0.016 × 0.022-inch stainless steel wire. A tooth attached by a retainer wire to only one neighbouring tooth is less resistant to torque than a tooth connected to two neighbouring teeth. Annealing a retainer wire with a flame reduces the stiffness of the wire markedly and can lead to a non-uniform and non-reproducible effect.

Towards plant wires.

PubMed

Adamatzky, Andrew

2014-08-01

In experimental laboratory studies we evaluate a possibility of making electrical wires from living plants. In scoping experiments we use lettuce seedlings as a prototype model of a plant wire. We approximate an electrical potential transfer function by applying direct current voltage to the lettuce seedlings and recording output voltage. We analyse oscillation frequencies of the output potential and assess noise immunity of the plant wires. Our findings will be used in future designs of self-growing wetware circuits and devices, and integration of plant-based electronic components into future and emergent bio-hybrid systems. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Retrospective Evaluation of Safety, Efficacy and Risk Factors for Pneumothorax in Simultaneous Localizations of Multiple Pulmonary Nodules Using Hook Wire System.

PubMed

Zhong, Yan; Xu, Xiao-Quan; Pan, Xiang-Long; Zhang, Wei; Xu, Hai; Yuan, Mei; Kong, Ling-Yan; Pu, Xue-Hui; Chen, Liang; Yu, Tong-Fu

2017-09-01

To evaluate the safety and efficacy of the hook wire system in the simultaneous localizations for multiple pulmonary nodules (PNs) before video-assisted thoracoscopic surgery (VATS), and to clarify the risk factors for pneumothorax associated with the localization procedure. Between January 2010 and February 2016, 67 patients (147 nodules, Group A) underwent simultaneous localizations for multiple PNs using a hook wire system. The demographic, localization procedure-related information and the occurrence rate of pneumothorax were assessed and compared with a control group (349 patients, 349 nodules, Group B). Multivariate logistic regression analyses were used to determine the risk factors for pneumothorax during the localization procedure. All the 147 nodules were successfully localized. Four (2.7%) hook wires dislodged before VATS procedure, but all these four lesions were successfully resected according to the insertion route of hook wire. Pathological diagnoses were acquired for all 147 nodules. Compared with Group B, Group A demonstrated significantly longer procedure time (p < 0.001) and higher occurrence rate of pneumothorax (p = 0.019). Multivariate logistic regression analysis indicated that position change during localization procedure (OR 2.675, p = 0.021) and the nodules located in the ipsilateral lung (OR 9.404, p < 0.001) were independent risk factors for pneumothorax. Simultaneous localizations for multiple PNs using a hook wire system before VATS procedure were safe and effective. Compared with localization for single PN, simultaneous localizations for multiple PNs were prone to the occurrence of pneumothorax. Position change during localization procedure and the nodules located in the ipsilateral lung were independent risk factors for pneumothorax.

Force systems in the initial phase of orthodontic treatment -- a comparison of different leveling arch wires.

PubMed

Fuck, Lars-Michael; Drescher, Dieter

2006-01-01

The determination of orthodontically-effective forces and moments places great demands on the technical equipment. Many patients report severe pain after fixed appliance insertion. Since it is assumed that pain from orthodontic appliances is associated with the force and moment levels applied to the teeth and since the occurrence of root resorption is a common therapeutic side effect, it would seem important to know the actual magnitudes of the components of the active orthodontic force systems. The aim of the present study was therefore to measure initial force systems produced by different leveling arch-wires in a complete multi-bracket appliance and to assess whether force and moment levels can be regarded as biologically acceptable or not. The actual bracket position in 42 patients was transferred onto a measurement model. Forces and moments produced by a super-elastic nickel-titanium (NiTi) archwire, a 6-strand stainless steel archwire, and a 7-strand super-elastic NiTi archwire were determined experimentally on different teeth. Average forces and moments produced by the super-elastic NiTi arch wires were found to be the highest. In spite if their larger diameter, the stranded arch wires' average force and moment levels were lower, especially that of the stranded super-elastic archwire. Nevertheless, maximum force levels sometimes exceeded recommended values in the literature and must be considered as too high. The measured arch wires' initial force systems differed significantly depending on the type of archwire and its material structure. Stranded arch wires produced lower force and moment levels, and we recommend their use in the initial phase of orthodontic treatment.

INTERIOR DETAIL, NORTH GARRET DOOR. THE WIRES VISIBLE ABOVE THE ...

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

INTERIOR DETAIL, NORTH GARRET DOOR. THE WIRES VISIBLE ABOVE THE DOOR ARE REMNANTS OF AN EARLY ELECTRICAL SYSTEM INSTALLED BY THE CEMETERY COMPANY - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

Corrosion Induced Loss of Capacity of Post Tensioned Seven Wire Strand Cable Used in Multistrand Anchor Systems Installed at Corps Projects

DTIC Science & Technology

2016-12-01

Universal Test Machine. .................. 7 Figure 2.2. Pull-test results of PT seven-wire strand cable surrounded by a quickset, steel - reinforced epoxy...13 Figure 2.7. Pull-test results of PT seven-wire strand cable surrounded by a quickset, steel - reinforced...surrounded by a thick layer of quickset, steel -reinforced epoxy and with 40% reduced wedges. ....................................................... 15

Development of a wear-resistant flux cored wire of Fe-C-Si-Mn-Cr-Ni-Mo-V system for deposit welding of mining equipment parts

NASA Astrophysics Data System (ADS)

Osetkovsky, I. V.; Kozyrev, N. A.; Kryukov, R. E.; Usoltsev, A. A.; Gusev, A. I.

2017-09-01

The effect of introduction of cobalt in the charge of the flux cored wire of Fe-C-Si-Mn-Cr-Ni-Mo-V system operating under abrasive and abrasive-shock loads is studied. In the laboratory conditions samples of flux cored wires were made, deposition was performed, the effect of cobalt on the hardness and the degree of wear was evaluated, metallographic studies were carried out. The influence of cobalt introduced into the charge of the flux cored wire of Fe-C-Si-Mn-Cr-Ni-Mo-V system on the structure, nature of nonmetallic inclusions, hardness and wear resistance of the weld metal was studied. In the laboratory conditions samples flux cored wire were made using appropriate powdered materials. As a carbon-fluorine-containing material dust from gas cleaning units of aluminum production was used. In the course of the study the chemical composition of the weld metal was determined, metallographic analysis was performed, mechanical properties were determined. As a result of the metallographic analysis the size of the former austenite grain, martensite dispersion in the structure of the weld metal, the level of contamination with its nonmetallic inclusions were established.

Nuclear Quantum Effects in H+ and OH- Diffusion Along Confined Water Wires from Ab Initio Path Integral Molecular Dyanmics

NASA Astrophysics Data System (ADS)

Rossi, Mariana; Ceriotti, Michele; Manolopoulos, David

Diffusion of H+ and OH- along water wires provides an efficient mechanism for charge transport that is exploited by biological systems and shows promise in technological applications. However, what is lacking for a better control and design of these systems is a thorough theoretical understanding of the diffusion process at the atomic scale. Here we consider H+ and OH- in finite water wires using density functional theory. We employ machine learning techniques to identify the charged species, thus obtaining an agnostic definition of the charge. We employ thermostated ring polymer molecular dynamics and extract a ``universal'' diffusion coefficient from simulations with different wire sizes by considering Langevin dynamics on the potential of mean force of the charged species. In the classical case, diffusion coefficients depend significantly on the potential energy surface, in particular on how dispersion forces modulate O-O distances. NQEs, however, make the diffusion less sensitive to the underlying potential and geometry of the wire, presumably making them more robust to environment fluctuations.

Health care's most wired. A wired exchange.

PubMed

Solovy, Alden

2004-08-01

There was a time when innovation in health care information technology meant being at the cutting edge of managerial systems. Hospitals made significant investments in financially oriented technology. In the past five years, the investment in clinical IT appears to have outstripped the investment in managerial systems, including enterprise resource planning aimed at improving the supply chain.

USAF/WL robust 300 C wire insulation system program status

NASA Technical Reports Server (NTRS)

Wong, Wing

1995-01-01

The objective of this program is to identify, develop, and demonstrate an optimum wire insulation system capable of continuous operation at 300 C which possesses a combination of superior electrical (AC or DC), mechanical, and physical properties over Kapton derived insulations described in MIL-W-81381 and those hybrid materials commonly known as TKT constructions.

Testing of a flat conductor cable baseboard system for residential and commercial wiring

NASA Technical Reports Server (NTRS)

Hankins, J. D.

1974-01-01

The results of extensive testing (mechanical, electrical, chemical, environmental, thermal, and analytical) are reported for a flat conductor cable baseboard system for residential and commercial wiring. In all of the tests, Underwriters Laboratories (UL) Standards, UL Tentative Test Programs, or Accepted Engineering Practices were followed during test selection, test setup, and test accomplishment.

USAF/WL robust 300 C wire insulation system program status

NASA Astrophysics Data System (ADS)

Wong, Wing

1995-11-01

The objective of this program is to identify, develop, and demonstrate an optimum wire insulation system capable of continuous operation at 300 C which possesses a combination of superior electrical (AC or DC), mechanical, and physical properties over Kapton derived insulations described in MIL-W-81381 and those hybrid materials commonly known as TKT constructions.

Robust 300 C wire insulation system

NASA Technical Reports Server (NTRS)

Nairus, John G.

1994-01-01

The objective of this program is to identify, develop, and demonstrate an optimum wire insulation system that is capable of continuous operation at 300 C. The system is to possess a combination of superior electrical (AC or DC), mechanical, and physical properties over the KAPTON (trademark) derived insulations described in MIL-W-81381 and those hybrid constructions identified in Air Force contract F33615-89-C-5606, commonly known as TKT constructions.

Development and evaluation of a reinforced polymeric biomaterial for use as an orthodontic wire

NASA Astrophysics Data System (ADS)

Zufall, Scott William

Composite archwires have the potential to provide esthetic and functional improvements over conventional wires. As part of an ongoing effort to bring these materials into general use, composite wires were fabricated using a photo-pultrusion manufacturing technique, and subsequently coated with a 10 mum layer of poly(chloro-p-xylylene). Coated and uncoated composites were subjected to several different evaluations to assess their ability to perform the functions of an orthodontic archwire. An investigation of the viscoelastic behavior of uncoated composite wires was conducted at a physiological temperature of 37°C using a bend stress relaxation test. Over 90 day testing periods, energy losses increased with decreasing reinforcement levels from to 8% of the initial wire stress. Final viscous losses were 1% for all reinforcement levels. Relaxed elastic moduli for the composite wires were comparable to the reported elastic moduli of conventional orthodontic wires that are typically used for initial and intermediate alignment procedures. Frictional characteristics were evaluated in passive and active configurations for uncoated composite wires against three contemporary orthodontic brackets. Kinetic coefficients of friction were the same for all wire-bracket combinations tested and were slightly lower than the reported coefficients of other initial and intermediate alignment wires. Wear patterns on the wires, which were largely caused by sharp leading edges of the bracket slots, were characteristic of plowing and cutting wear behaviors. This wear caused glass fibers to be released from the surface of the wires, presenting a potential irritant. Coated composite wires were subjected to the same frictional analysis as the uncoated wires. A mathematical model of the archwire-bracket system was derived using engineering mechanics, and used to define a coefficient of binding. The coating increased the frictional coefficients of the wires by 72%, yet the binding coefficient was unchanged. When frictional data for initial and intermediate alignment wires were compared, the coated composites had higher friction than all but one couple. However, binding coefficients were comparable. Glass fibers were contained for all testing conditions, although the coating was often damaged by plowing or cutting wear. Overall, the coating improved the clinical acceptability of the composite wires.

Design of a Hybrid (Wired/Wireless) Acquisition Data System for Monitoring of Cultural Heritage Physical Parameters in Smart Cities

PubMed Central

García Diego, Fernando-Juan; Esteban, Borja; Merello, Paloma

2015-01-01

Preventive conservation represents a working method and combination of techniques which helps in determining and controlling the deterioration process of cultural heritage in order to take the necessary actions before it occurs. It is acknowledged as important, both in terms of preserving and also reducing the cost of future conservation measures. Therefore, long-term monitoring of physical parameters influencing cultural heritage is necessary. In the context of Smart Cities, monitoring of cultural heritage is of interest in order to perform future comparative studies and load information into the cloud that will be useful for the conservation of other heritage sites. In this paper the development of an economical and appropriate acquisition data system combining wired and wireless communication, as well as third party hardware for increased versatility, is presented. The device allows monitoring a complex network of points with high sampling frequency, with wired sensors in a 1-wire bus and a wireless centralized system recording data for monitoring of physical parameters, as well as the future possibility of attaching an alarm system or sending data over the Internet. This has been possible with the development of three board’s designs and more than 5000 algorithm lines. System tests have shown an adequate system operation. PMID:25815447

Design of a hybrid (wired/wireless) acquisition data system for monitoring of cultural heritage physical parameters in Smart Cities.

PubMed

García Diego, Fernando-Juan; Esteban, Borja; Merello, Paloma

2015-03-25

Preventive conservation represents a working method and combination of techniques which helps in determining and controlling the deterioration process of cultural heritage in order to take the necessary actions before it occurs. It is acknowledged as important, both in terms of preserving and also reducing the cost of future conservation measures. Therefore, long-term monitoring of physical parameters influencing cultural heritage is necessary. In the context of Smart Cities, monitoring of cultural heritage is of interest in order to perform future comparative studies and load information into the cloud that will be useful for the conservation of other heritage sites. In this paper the development of an economical and appropriate acquisition data system combining wired and wireless communication, as well as third party hardware for increased versatility, is presented. The device allows monitoring a complex network of points with high sampling frequency, with wired sensors in a 1-wire bus and a wireless centralized system recording data for monitoring of physical parameters, as well as the future possibility of attaching an alarm system or sending data over the Internet. This has been possible with the development of three board's designs and more than 5000 algorithm lines. System tests have shown an adequate system operation.

Shaping ability of two M-wire and two traditional nickel-titanium instrumentation systems in S-shaped resin canals.

PubMed

Ceyhanli, K T; Kamaci, A; Taner, M; Erdilek, N; Celik, D

2015-01-01

The aim of this study was to evaluate the shaping effects of two M-wire and two traditional nickel-titanium (NiTi) rotary systems in simulated S-shaped resin canals. Forty simulated S-shaped canals in resin blocks were instrumented with two traditional (ProTaper, Sendoline S5) and two M-wire (WaveOne, GT series X) NiTi systems according to the manufacturers' instructions. Ten resin blocks were used for each system. Pre- and post-instrumentation images were captured using a stereomicroscope and superimposed with an image program. Canal transportation, material removal, and aberrations were evaluated and recorded as numeric parameters. Data were analyzed using one-way ANOVA and post-hoc Tukey tests with a 95% confidence interval. There were significant differences between systems in terms of transportation and material removal (P<0.05). Coronal danger zone was the most common aberration. Within the limits of this ex vivo study, it was found that the manufacturing methods (M-wire or traditional NiTi) and kinematics (rotary or reciprocating motion) did not affect the shaping abilities of the systems. The extended file designs of highly tapered NiTi systems (ProTaper, WaveOne) resulted in greater deviations from the original root canal trace and more material removal when compared to less tapered systems (Sendoline S5, GT series X).

Specification and testing for power by wire aircraft

NASA Technical Reports Server (NTRS)

Hansen, Irving G.; Kenney, Barbara H.

1993-01-01

A power by wire aircraft is one in which all active functions other than propulsion are implemented electrically. Other nomenclature are 'all electric airplane,' or 'more electric airplane.' What is involved is the task of developing and certifying electrical equipment to replace existing hydraulics and pneumatics. When such functions, however, are primary flight controls which are implemented electrically, new requirements are imposed that were not anticipated by existing power system designs. Standards of particular impact are the requirements of ultra-high reliability, high peak transient bi-directional power flow, and immunity to electromagnetic interference and lightning. Not only must the electromagnetic immunity of the total system be verifiable, but box level tests and meaningful system models must be established to allow system evaluation. This paper discusses some of the problems, the system modifications involved, and early results in establishing wiring harness and interface susceptibility requirements.

Portable Electron-Beam Free-Form Fabrication System

NASA Technical Reports Server (NTRS)

Watson, J. Kevin; Petersen, Daniel D.; Taminger, Karen M.; Hafley, Robert A.

2005-01-01

A portable electron-beam free-form fabrication (EB F3) system, now undergoing development, is intended to afford a capability for manufacturing metal parts in nearly net sizes and shapes. Although the development effort is oriented toward the eventual use of systems like this one to supply spare metal parts aboard spacecraft in flight, the basic system design could also be adapted to terrestrial applications in which there are requirements to supply spare parts on demand at locations remote from warehouses and conventional manufacturing facilities. Prior systems that have been considered for satisfying the same requirements (including prior free-form fabrication systems) are not easily portable because of their bulk and massive size. The mechanical properties of the components that such systems produce are often inferior to the mechanical properties of the corresponding original, conventionally fabricated components. In addition, the prior systems are not efficient in the utilization of energy and of feedstock. In contrast, the present developmental system is designed to be sufficiently compact and lightweight to be easily portable, to utilize both energy and material more efficiently, and to produce components that have mechanical properties approximating those of the corresponding original components. The developmental EB F3 system will include a vacuum chamber and associated vacuum pumps, an electron-beam gun and an associated power supply, a multiaxis positioning subsystem, a precise wire feeder, and an instrumentation system for monitoring and control. The electron-beam gun, positioning subsystem, and wire feeder will be located inside the vacuum chamber (see figure). The electron beam gun and the wire feeder will be mounted in fixed positions inside the domed upper portion of the vacuum chamber. The positioning subsystem and ports for the vacuum pumps will be located on a base that could be dropped down to provide full access to the interior of the chamber when not under vacuum. During operation, wire will be fed to a fixed location, entering the melted pool created by the electron beam. Heated by the electron beam, the wire will melt and fuse to either the substrate or with the previously deposited metal wire fused on top of the positioning table. Based on a computer aided design (CAD) model and controlled by a computer, the positioning subsystem

Semi-automatic central-chest lymph-node definition from 3D MDCT images

NASA Astrophysics Data System (ADS)

Lu, Kongkuo; Higgins, William E.

2010-03-01

Central-chest lymph nodes play a vital role in lung-cancer staging. The three-dimensional (3D) definition of lymph nodes from multidetector computed-tomography (MDCT) images, however, remains an open problem. This is because of the limitations in the MDCT imaging of soft-tissue structures and the complicated phenomena that influence the appearance of a lymph node in an MDCT image. In the past, we have made significant efforts toward developing (1) live-wire-based segmentation methods for defining 2D and 3D chest structures and (2) a computer-based system for automatic definition and interactive visualization of the Mountain central-chest lymph-node stations. Based on these works, we propose new single-click and single-section live-wire methods for segmenting central-chest lymph nodes. The single-click live wire only requires the user to select an object pixel on one 2D MDCT section and is designed for typical lymph nodes. The single-section live wire requires the user to process one selected 2D section using standard 2D live wire, but it is more robust. We applied these methods to the segmentation of 20 lymph nodes from two human MDCT chest scans (10 per scan) drawn from our ground-truth database. The single-click live wire segmented 75% of the selected nodes successfully and reproducibly, while the success rate for the single-section live wire was 85%. We are able to segment the remaining nodes, using our previously derived (but more interaction intense) 2D live-wire method incorporated in our lymph-node analysis system. Both proposed methods are reliable and applicable to a wide range of pulmonary lymph nodes.

Influences on lifetime of wire ropes in traction lifts

NASA Astrophysics Data System (ADS)

Vogel, W.

2016-05-01

Traction lifts are complex systems with rotating and translating moving masses, springs and dampers and several system inputs from the lifts and the users. The wire ropes are essential mechanical elements. The mechanical properties of the ropes in use depend on the rope construction, the load situation, nonlinearities and the lift dimensions. The mechanical properties are important for the proper use in lifts and the ride quality. But first of all the wire ropes (for all other suspension means as well) have to satisfy the safety relevant requirements sufficient lifetime, reliable determination of discard and sufficient and limited traction capacity. The lifetime of the wire ropes better the number of trips until rope discard depends on a lot of parameters of the rope and the rope application eg use of plastic deflection sheaves and reverse bending layouts. New challenges for rope lifetime are resulting from the more or less open D/d-ratio limits possible by certificates concerning the examination of conformity by notified bodies. This paper will highlight the basics of wire rope technology, the endurance and lifetime of wire ropes running over sheaves, and the different influences from the ropes and more and more important from the lift application parameters. Very often underestimated are the influences of transport, storage, installation and maintenance. With this background we will lead over to the calculation methods of wire rope lifetime considering the actual findings of wire rope endurance research. We'll show in this paper new and innovative facts as the influence of rope length and size factor in the lifetime formular, the reduction of lifetime caused by traction grooves, the new model for the calculation in reverse bending operations and the statistically firmed possibilities for machine roomless lifts (MRL) under very small bending conditions.

Percutaneous Kirschner Wire Versus Commercial Implant for Hammertoe Repair: A Cost-Effectiveness Analysis.

PubMed

Albright, Rachel H; Waverly, Brett J; Klein, Erin; Weil, Lowell; Weil, Lowell S; Fleischer, Adam E

Hammertoe deformities are one of the most common foot deformities, affecting up to one third of the general population. Fusion of the joint can be achieved with various devices, with the current focus on percutaneous Kirschner (K)-wire fixation or commercial intramedullary implant devices. The purpose of the present study was to determine whether surgical intervention with percutaneous K-wire fixation versus commercial intramedullary implant is more cost effective for proximal interphalangeal joint arthrodesis in hammertoe surgery. A formal cost-effectiveness analysis using a decision analytic tree model was conducted to investigate the healthcare costs and outcomes associated with either K-wire or commercial intramedullary implant fixation. The outcomes assessed included long-term costs, quality-adjusted life-years (QALYs), and incremental cost per QALY gained. Costs were evaluated from the healthcare system perspective and are expressed in U.S. dollars at a 2017 price base. Our results found that commercial implants were minimally more effective than K-wires but carried significantly higher costs. The total cost for treatment with percutaneous K-wire fixation was $5041 with an effectiveness of 0.82 QALY compared with a commercial implant cost of $6059 with an effectiveness of 0.83 QALY. The incremental cost-effectiveness ratio of commercial implants was $146,667. With an incremental cost-effectiveness ratio of >$50,000, commercial implants failed to justify their proposed benefits to outweigh their cost compared to percutaneous K-wire fixation. In conclusion, percutaneous K-wire fixation would be preferred for arthrodesis of the proximal interphalangeal joint for hammertoes from a healthcare system perspective. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

46 CFR 154.801 - Pressure relief systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... than the MARVS; (3) Have a fitting for sealing wire that prevents the set pressure from being changed without breaking the sealing wire; (4) Be fitted on the cargo tank to remain in the vapor phase under...

46 CFR 154.801 - Pressure relief systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... than the MARVS; (3) Have a fitting for sealing wire that prevents the set pressure from being changed without breaking the sealing wire; (4) Be fitted on the cargo tank to remain in the vapor phase under...

46 CFR 154.801 - Pressure relief systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... than the MARVS; (3) Have a fitting for sealing wire that prevents the set pressure from being changed without breaking the sealing wire; (4) Be fitted on the cargo tank to remain in the vapor phase under...

46 CFR 154.801 - Pressure relief systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... than the MARVS; (3) Have a fitting for sealing wire that prevents the set pressure from being changed without breaking the sealing wire; (4) Be fitted on the cargo tank to remain in the vapor phase under...

Development of a Production Ready Automated Wire Delivery System

NASA Technical Reports Server (NTRS)

1997-01-01

The current development effort is a Phase 3 research study entitled "A Production Ready Automated Wire Delivery System", contract number NAS8-39933, awarded to Nichols Research Corporation (NRC). The goals of this research study were to production harden the existing Automated Wire Delivery (AWDS) motion and sensor hardware and test the modified AWDS in a range of welding applications. In addition, the prototype AWDS controller would be moved to the VME bus platform by designing, fabricating and testing a single board VME bus AWDS controller. This effort was to provide an AWDS that could transition from the laboratory environment to production operations. The project was performed in two development steps. Step 1 modified and tested an improved MWG. Step 2 developed and tested the AWDS single board VME bus controller. Step 3 installed the Wire Pilot in a Weld Controller with the imbedded VME bus controller.

A portable borehole temperature logging system using the four-wire resistance method

NASA Astrophysics Data System (ADS)

Erkan, Kamil; Akkoyunlu, Bülent; Balkan, Elif; Tayanç, Mete

2017-12-01

High-quality temperature-depth information from boreholes with a depth of 100 m or more is used in geothermal studies and in studies of climate change. Electrical wireline tools with thermistor sensors are capable of measuring borehole temperatures with millikelvin resolution. The use of a surface readout mode allows analysis of the thermally conductive state of a borehole, which is especially important for climatic and regional heat flow studies. In this study we describe the design of a portable temperature logging tool that uses the four-wire resistance measurement method. The four-wire method enables the elimination of cable resistance effects, thus allowing millikelvin resolution of temperature data at depth. A preliminary two-wire model of the system is also described. The portability of the tool enables one to collect data from boreholes down to 300 m, even in locations with limited accessibility.

Transmission line design for a power distribution system at 20 kHz for aircraft

NASA Technical Reports Server (NTRS)

Zelby, L. W.; Mathes, J. B.; Shawver, J. W.

1986-01-01

A low inductance, low characteristic impedance transmission line was designed for a 20 kHz power distribution system. Several different conductor configurations were considered: strip lines, interdigitated metal ribbons, and standard insulated wires in multiwire configurations (circular and rectangular cylindrical arrangements). The final design was a rectangular arrangement of multiple wires of the same gauge with alternating polarities from wire to wire. This offered the lowest inductance per unit length (on the order of several nanohenries/meter) and the lowest characteristic impedance (on the order of one Ohm). Standard multipin connectors with gold-plated elements were recommended with this transmission line, the junction boxes to be internally connected with flat metal ribbons for low inductance, and the line to be constructed in sections of suitable length. Computer programs for the calculation of inductance of multiwire lines and of capacitances of strip lines were developed.

Shot noise enhancement from non-equilibrium plasmons in Luttinger liquid junctions.

PubMed

Kim, Jaeuk U; Kinaret, Jari M; Choi, Mahn-Soo

2005-06-29

We consider a quantum wire double junction system with each wire segment described by a spinless Luttinger model, and study theoretically shot noise in this system in the sequential tunnelling regime. We find that the non-equilibrium plasmonic excitations in the central wire segment give rise to qualitatively different behaviour compared to the case with equilibrium plasmons. In particular, shot noise is greatly enhanced by them, and exceeds the Poisson limit. We show that the enhancement can be explained by the emergence of several current-carrying processes, and that the effect disappears if the channels effectively collapse to one because of fast plasmon relaxation processes, for example.

Semiautomatic cold wire feeder systems increase GTA productivity

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

Richardson, M.

1995-01-01

Often, the focus of attempts to increase GTA welding productivity is on studies to determine if justification exists for additional workstations, or for the investment in new fully automated dedicated welding fixtures. Often less costly and simpler solutions can bring about the necessary means to increase production rates and reduce operating costs. For short-run production applications, it is almost impossible to justify the substantial investment in a dedicated automatic fixture. Now, low cost GTA cold wire feeder systems are within the reach of even small shops. The paper views how cold wire equipment has been applied in several GTAW applicationsmore » to improve results.« less

Shot noise enhancement from non-equilibrium plasmons in Luttinger liquid junctions

NASA Astrophysics Data System (ADS)

Kim, Jaeuk U.; Kinaret, Jari M.; Choi, Mahn-Soo

2005-06-01

We consider a quantum wire double junction system with each wire segment described by a spinless Luttinger model, and study theoretically shot noise in this system in the sequential tunnelling regime. We find that the non-equilibrium plasmonic excitations in the central wire segment give rise to qualitatively different behaviour compared to the case with equilibrium plasmons. In particular, shot noise is greatly enhanced by them, and exceeds the Poisson limit. We show that the enhancement can be explained by the emergence of several current-carrying processes, and that the effect disappears if the channels effectively collapse to one because of fast plasmon relaxation processes, for example.

Full-vectorial finite element method in a cylindrical coordinate system for loss analysis of photonic wire bends

NASA Astrophysics Data System (ADS)

Kakihara, Kuniaki; Kono, Naoya; Saitoh, Kunimasa; Koshiba, Masanori

2006-11-01

This paper presents a new full-vectorial finite-element method in a local cylindrical coordinate system, to effectively analyze bending losses in photonic wires. The discretization is performed in the cross section of a three-dimensional curved waveguide, using hybrid edge/nodal elements. The solution region is truncated by anisotropic, perfectly matched layers in the cylindrical coordinate system, to deal properly with leaky modes of the waveguide. This approach is used to evaluate bending losses in silicon wire waveguides. The numerical results of the present approach are compared with results calculated with an equivalent straight waveguide approach and with reported experimental data. These comparisons together demonstrate the validity of the present approach based on the cylindrical coordinate system and also clarifies the limited validity of the equivalent straight waveguide approximation.

Multi-wire slurry wafering demonstrations. [slicing silicon ingots for solar arrays

NASA Technical Reports Server (NTRS)

Chen, C. P.

1978-01-01

Ten slicing demonstrations on a multi-wire slurry saw, made to evaluate the silicon ingot wafering capabilities, reveal that the present sawing capabilities can provide usable wafer area from an ingot 1.05m/kg (e.g. kerf width 0.135 mm and wafer thickness 0.265 mm). Satisfactory surface qualities and excellent yield of silicon wafers were found. One drawback is that the add-on cost of producing water from this saw, as presently used, is considerably higher than other systems being developed for the low-cost silicon solar array project (LSSA), primarily because the saw uses a large quantity of wire. The add-on cost can be significantly reduced by extending the wire life and/or by rescue of properly plated wire to restore the diameter.

Silane and Germane Molecular Electronics.

PubMed

Su, Timothy A; Li, Haixing; Klausen, Rebekka S; Kim, Nathaniel T; Neupane, Madhav; Leighton, James L; Steigerwald, Michael L; Venkataraman, Latha; Nuckolls, Colin

2017-04-18

This Account provides an overview of our recent efforts to uncover the fundamental charge transport properties of Si-Si and Ge-Ge single bonds and introduce useful functions into group 14 molecular wires. We utilize the tools of chemical synthesis and a scanning tunneling microscopy-based break-junction technique to study the mechanism of charge transport in these molecular systems. We evaluated the fundamental ability of silicon, germanium, and carbon molecular wires to transport charge by comparing conductances within families of well-defined structures, the members of which differ only in the number of Si (or Ge or C) atoms in the wire. For each family, this procedure yielded a length-dependent conductance decay parameter, β. Comparison of the different β values demonstrates that Si-Si and Ge-Ge σ bonds are more conductive than the analogous C-C σ bonds. These molecular trends mirror what is seen in the bulk. The conductance decay of Si and Ge-based wires is similar in magnitude to those from π-based molecular wires such as paraphenylenes However, the chemistry of the linkers that attach the molecular wires to the electrodes has a large influence on the resulting β value. For example, Si- and Ge-based wires of many different lengths connected with a methyl-thiomethyl linker give β values of 0.36-0.39 Å -1 , whereas Si- and Ge-based wires connected with aryl-thiomethyl groups give drastically different β values for short and long wires. This observation inspired us to study molecular wires that are composed of both π- and σ-orbitals. The sequence and composition of group 14 atoms in the σ chain modulates the electronic coupling between the π end-groups and dictates the molecular conductance. The conductance behavior originates from the coupling between the subunits, which can be understood by considering periodic trends such as bond length, polarizability, and bond polarity. We found that the same periodic trends determine the electric field-induced breakdown properties of individual Si-Si, Ge-Ge, Si-O, Si-C, and C-C bonds. Building from these studies, we have prepared a system that has two different, alternative conductance pathways. In this wire, we can intentionally break a labile, strained silicon-silicon bond and thereby shunt the current through the secondary conduction pathway. This type of in situ bond-rupture provides a new tool to study single molecule reactions that are induced by electric fields. Moreover, these studies provide guidance for designing dielectric materials as well as molecular devices that require stability under high voltage bias. The fundamental studies on the structure/function relationships of the molecular wires have guided the design of new functional systems based on the Si- and Ge-based wires. For example, we exploited the principle of strain-induced Lewis acidity from reaction chemistry to design a single molecule switch that can be controllably switched between two conductive states by varying the distance between the tip and substrate electrodes. We found that the strain intrinsic to the disilaacenaphthene scaffold also creates two state conductance switching. Finally, we demonstrate the first example of a stereoelectronic conductance switch, and we demonstrate that the switching relies crucially on the electronic delocalization in Si-Si and Ge-Ge wire backbones. These studies illustrate the untapped potential in using Si- and Ge-based wires to design and control charge transport at the nanoscale and to allow quantum mechanics to be used as a tool to design ultraminiaturized switches.

The main beam efficiency of corner cube reflectors

NASA Astrophysics Data System (ADS)

Vowinkel, B.

1986-01-01

A computer model for the calculation of the beam pattern and the main beam efficiency of corner cube reflectors used in submillimeter heterodyne systems is described. The model includes possible mismatches at the termination of the wire antenna, the attenuation of the wave along the wire due to emission and the contribution of the wire bend to the antenna pattern. Measurements with a scale model at 15 GHz show good agreement between experiment and theory.

Steering of quantum waves: Demonstration of Y-junction transistors using InAs quantum wires

NASA Astrophysics Data System (ADS)

Jones, Gregory M.; Qin, Jie; Yang, Chia-Hung; Yang, Ming-Jey

2005-06-01

In this paper we demonstrate using an InAs quantum wire Y-branch switch that the electron wave can be switched to exit from the two drains by a lateral gate bias. The gating modifies the electron wave functions as well as their interference pattern, causing the anti-correlated, oscillatory transconductances. Our result suggests a new transistor function in a multiple-lead ballistic quantum wire system.

A Comparative Study of Bio Degradation of Various Orthodontic Arch Wires: An In Vitro Study

PubMed Central

Gopikrishnan, S; Melath, Anil; Ajith, V V; Mathews, N Binoy

2015-01-01

Background: Orthodontic wires are the corner stones of the science and art of orthodontics and they remain in the patient’s mouth for a prolonged period of 18-24 months. It is but natural to expect that they will undergo some biodegradation when in the oral environment during that period. This study aims to compare the biodegradation characteristics of four different orthodontic wires, stainless steel, nickel titanium (NiTi), titanium molybdenum alloy (TMA), and copper NiTi and to assess whether these biodegradation products, are within acceptable limits. Materials and Methods: This study involved the incubation of four different wires in artificial saliva and analyzing the amount of metal released from them at the end of a 28 days study period. The metals analyzed for where nickel, chromium, copper, cobalt, manganese, iron, molybdenum, and titanium. The artificial saliva was changed on days 7, 14, and 21 to prevent the saturation of metals in the artificial saliva. At the end of 28 days, these four samples of artificial saliva of each wire were mixed together and analyzed for the eight metals using an inductively coupled plasma spectroscope. Results: The results showed only the release of nickel, chromium, and iron from stainless steel wire, nickel from NiTi wire, nickel, and chromium from copper NiTi and none from TMA wire. Conclusion: The metals released from arch wires are of such minute quantities to be of any biologic hazard. The amount of metals released is well within acceptable biocompatible limits. Though this study has analyzed the biodegradation of various orthodontic wires, orthodontic wires are never used alone in mechanotherapy. Orthodontic wires along with multiband appliance system with which it is always used and in combination with accessories like face bows may release more metals. PMID:25709360

Composite superconducting wires obtained by high-rate tinning in molten Bi-Pb-Sr-Ca-Cu-O system

NASA Technical Reports Server (NTRS)

Grozav, A. D.; Konopko, L. A.; Leporda, N. I.

1990-01-01

The preparation of high-T(sub c) superconducting long composite wires by short-time tinning of the metal wires in a molten Bi-Pb-Sr-Ca-Cu-O compound is discussed. The application of this method to the high-T(sub c) materials is tested, possibly for the first time. The initial materials used for this experiment were ceramic samples with nominal composition Bi(1.5)Pb(0.5)Sr2Ca2Cu3O(x) and T(sub c) = 80 K prepared by the ordinary solid-state reaction, and industrial copper wires from 100 to 400 microns in diameter and from 0.5 to 1 m long. The continuously moving wires were let through a small molten zone (approximately 100 cubic mm). The Bi-based high-T(sub c) ceramics in a molten state is a viscous liquid and it has a strongly pronounced ability to spread on metal wire surfaces. The maximum draw rate of the Cu-wire, at which a dense covering is still possible, corresponds to the time of direct contact of wire surfaces and liquid ceramics for less than 0.1 s. A high-rate draw of the wire permits a decrease in the reaction of the oxide melt and Cu-wire. This method of manufacture led to the fabrication of wire with a copper core in a dense covering with uniform thickness of about h approximately equal to 5 to 50 microns. Composite wires with h approximately equal to 10 microns (h/d approximately equal to 0.1) sustained bending on a 15 mm radius frame without cracking during flexing.