Science.gov

Sample records for crawler tractors

  1. Miniature pipe crawler tractor

    SciTech Connect

    McKay, M.D.; Anderson, M.O.; Ferrante, T.A.; Willis, W.D.

    2000-03-14

    A pipe crawler tractor may comprise a half tractor assembly having a first base drive wheel, a second base drive wheel, and a top drive wheel. The drive wheels are mounted in spaced-apart relation so that the top drive wheel is positioned between the first and second base drive wheels. The mounting arrangement is also such that the first and second base drive wheels contact the inside surface of the pipe at respective first and second positions and so that the top drive wheel contacts the inside surface of the pipe at a third position, the third position being substantially diametrically opposed to the first and second positions. A control system connected to the half tractor assembly controls the rotation of the first base wheel, the second base wheel, and the top drive wheel to move the half tractor assembly within the pipe.

  2. Miniature pipe crawler tractor

    DOEpatents

    McKay, Mark D.; Anderson, Matthew O.; Ferrante, Todd A.; Willis, W. David

    2000-01-01

    A pipe crawler tractor may comprise a half tractor assembly having a first base drive wheel, a second base drive wheel, and a top drive wheel. The drive wheels are mounted in spaced-apart relation so that the top drive wheel is positioned between the first and second base drive wheels. The mounting arrangement is also such that the first and second base drive wheels contact the inside surface of the pipe at respective first and second positions and so that the top drive wheel contacts the inside surface of the pipe at a third position, the third position being substantially diametrically opposed to the first and second positions. A control system connected to the half tractor assembly controls the rotation of the first base wheel, the second base wheel, and the top drive wheel to move the half tractor assembly within the pipe.

  3. Self-Pacing a Gross Motor Skills Course: Crawler Tractor Operator, MOS 62E20.

    ERIC Educational Resources Information Center

    Brennan, Mark F.; Taylor, John E.

    As part of the Army's emphasis on performance-oriented instruction in training centers, a study was conducted to determine the feasibility of using self-paced instruction in a gross motor skills course. The Crawler Tractor Operator Course, a seven-week heavy equipment course conducted at Fort Leonard Wood, Missouri was selected for the study…

  4. Pipe crawlers: Versatile adaptations for real applications

    SciTech Connect

    Hapstack, M.; Talarek, T.R.

    1990-01-01

    A problem at the Savannah River Site requires the unique application of a pipe crawler. A number of stainless steel pipes buried in concrete require ultrasonic inspection of the heat affected zones of the welds for detection of flaws or cracks. The paper describes the utilization of an inch-worm motion pipe crawler which negotiates a 90 degree reducing elbow with significant changes in diameter and vertical sections before entering the area of concern. After a discussion of general considerations and problem description, special requirements to meet the objectives and the design approach regarding the tractor, control system, instrument carriage, and radiation protection are discussed. 2 refs., 11 figs. (MB)

  5. VIEW OF CRAWLER TRANSPORTER NO. 1 (LEFT) AND CRAWLER TRANSPORTER ...

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

    VIEW OF CRAWLER TRANSPORTER NO. 1 (LEFT) AND CRAWLER TRANSPORTER NO. 2 (RIGHT) AT PARKING/MAINTENANCE SITE. - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  6. DWPF Melt Cell Crawler

    SciTech Connect

    Ward, C.R.

    2003-04-08

    On December 2, 2002, Remote and Specialty Equipment Systems (RSES) of the Savannah River Technology Center (SRTC) was requested to build a remotely operated crawler to assist in cleaning the Defense Waste Processing Facility (DWPF) melt cell floor of glass, tools, and other debris. The crawler was to assist a grapple and vacuum system in cleaning the cell. The crawler was designed to push glass and debris into piles so that the grapple could pick up the material and place it in waste bins. The crawler was also designed to maneuver the end of the vacuum hose, if needed. In addition, the crawler was designed to clean the area beneath the cell worktable that was inaccessible to the grapple and vacuum system. Originally, the system was to be ready for deployment by December 17. The date was moved up to December 12 to better utilize the available time for clean up. The crawler was designed and built in 10 days and completed cleaning the melt cell in 8 days. Due to initial problems with the grapple and vacuum system, the crawler completed essentially all of the cleanup tasks by itself. The crawler also cleaned an area on the west side of the cell that was not initially slated for cleaning.

  7. Extendable pipe crawler

    DOEpatents

    Hapstack, Mark

    1991-01-01

    A pipe crawler having a front leg assembly and a back leg assembly connected together by two air cylinders, each leg assembly having four extendable legs and a pair of actuators for sliding the extendable legs radially outward to increase the range of the legs when the pipe crawler enters a section of a pipe having a larger diameter. The crawler crawls by "inchworm"-like motion, the front leg assembly and back leg assembly alternately engaging and disengaging the wall of the pipe to hold the pipe crawler as the air cylinders alternately advance the front leg assembly and bring up the rear leg assembly. The pair of actuators of each leg assembly are parallel, adjacent and opposing acting so that each slides two adjacent extendable legs radially outward.

  8. Extendable pipe crawler

    DOEpatents

    Hapstack, M.

    1991-05-28

    A pipe crawler is described having a front leg assembly and a back leg assembly connected together by two air cylinders, each leg assembly having four extendable legs and a pair of actuators for sliding the extendable legs radially outward to increase the range of the legs when the pipe crawler enters a section of a pipe having a larger diameter. The crawler crawls by inchworm'-like motion, the front leg assembly and back leg assembly alternately engaging and disengaging the wall of the pipe to hold the pipe crawler as the air cylinders alternately advance the front leg assembly and bring up the rear leg assembly. The pair of actuators of each leg assembly are parallel, adjacent and opposing acting so that each slides two adjacent extendable legs radially outward. 5 figures.

  9. Tether crawler system

    NASA Technical Reports Server (NTRS)

    Swanson, Frank R.

    1986-01-01

    A crawler system is designed to move a low-g/variable-g laboratory module along a tether between the Space Station and an attached space platform. An analysis is made of the effects of control law parameter change on the displacement, velocity, and acceleration of the crawler system. The control law is then modified by the addition of a constant-velocity section and the values of distance traveled, velocity, and acceleration are analyzed as a function of time. The power and torque equations are derived for a crawler system moving along a tether in orbit and numerical values of power and torque required for each prescribed movement are calculated versus time for four different cases using the control laws. A two-step control sequence is selected to permit initial location along the tether by distance traveled, followed by a vernier movement to reach the final desired constant net acceleration level. The components for the control system are identified and arranged in a block disgram configuration. The support subsystems are also identified. The sections were integrated to develop a procedure for the determination of crawler system performance requirements and the initial design of tether crawler systems.

  10. Pipe crawler apparatus

    DOEpatents

    Hovis, Gregory L.; Erickson, Scott A.; Blackmon, Bruce L.

    2002-01-01

    A pipe crawler apparatus particularly useful for 3-inch and 4-inch diameter pipes is provided. The pipe crawler apparatus uses a gripping apparatus in which a free end of a piston rod is modified with a bearing retaining groove. Bearings, placed within the groove, are directed against a camming surface of three respective pivoting support members. The non-pivoting ends of the support members carry a foot-like gripping member that, upon pivoting of the support member, engages the interior wall of the pipe.

  11. Crawler Solids Unknown Analysis

    NASA Technical Reports Server (NTRS)

    Frandsen, Athela

    2016-01-01

    Crawler Transporter (CT) #2 has been undergoing refurbishment to carry the Space Launch System (SLS). After returning to normal operation, multiple filters of the gear box lubrication system failed/clogged and went on bypass during a test run to the launch pad. Analysis of the filters was done in large part with polarized light microscopy (PLM) to identify the filter contaminates and the source of origin.

  12. Progress report on Bertelsen research and development of an air cushion crawler all-terrain vehicle

    NASA Astrophysics Data System (ADS)

    Bertelsen, W. R.

    1987-06-01

    The ACV is an exceptional amphibian but it is not, nor is any other existing craft, an all-terrain vehicle (ATV). Using the best elements of the ACV in an air-cushion crawler tractor, a true ATV can be attained. A conventional crawler drive train will propel two tracks as pressurized, propulsive pontoons. The key to a successful ATV is in perfecting efficient, durable, sliding seals to allow the belt to move in its orbit around the track unit and maintain its internal pressure. After deriving the adequate seal, a 12 inch wide x 86 inch long endless rubber belt was fitted bilateral seals and slide plates with internal guide wheels fore and aft with a 21 inch wheel base. From this approximately one-quarter scale model, full-scale air track crawlers, true ATVs, of any size and capacity can be produced.

  13. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, W.T.

    1992-06-16

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long as a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler. 8 figs.

  14. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, William T.

    1992-01-01

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler.

  15. Pipe crawler with stabilizing midsection

    SciTech Connect

    Zollinger, W.T.; Treanor, R.C.

    1993-09-20

    This invention is comprised of a pipe crawler having a midsection that provides the stability and flexibility to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in ``inch worm`` fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting.

  16. Pipe crawler with stabilizing midsection

    DOEpatents

    Zollinger, William T.; Treanor, Richard C.

    1994-01-01

    A pipe crawler having a midsection that provides the stability and flexibty to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in "inch worm" fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting.

  17. Pipe crawler with stabilizing midsection

    DOEpatents

    Zollinger, W.T.; Treanor, R.C.

    1994-12-27

    A pipe crawler is described having a midsection that provides the stability and flexibility to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in ''inch worm'' fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting. 5 figures.

  18. H-Canyon Recovery Crawler

    SciTech Connect

    Kriikku, E. M.; Hera, K. R.; Marzolf, A. D.; Phillips, M. H.

    2015-08-01

    The Nuclear Material Disposition Project group asked the Savannah River National Lab (SRNL) Research and Development Engineering (R&DE) department to help procure, test, and deploy a remote crawler to recover the 2014 Inspection Crawler (IC) that tipped over in the H-Canyon Air Exhaust Tunnel. R&DE wrote a Procurement Specification for a Recovery Crawler (RC) and SRNS Procurement Department awarded the contract to Power Equipment Manufacturing Inc. (PEM). The PEM RC was based on their standard sewer inspection crawler with custom arms and forks added to the front. The arms and forks would be used to upright the 2014 Inspection Crawler. PEM delivered the RC and associated cable reel, 2014 Inspection Crawler mockup, and manuals in late April 2015. R&DE and the team tested the crawler in May of 2015 and made modifications based on test results and Savannah River Site (SRS) requirements. R&DE delivered the RC to H-Area at the end of May. The team deployed the RC on June 9, 10, and 11, 2015 in the H-Canyon Air Exhaust Tunnel. The RC struggled with some obstacles in the tunnel, but eventually made it to the IC. The team spent approximately five hours working to upright the IC and eventually got it on its wheels. The IC travelled approximately 20 feet and struggled to drive over debris on the air tunnel floor. Unfortunately the IC tripped over trying to pass this obstacle. The team decided to leave the IC in this location and inspect the tunnel with the RC. The RC passed the IC and inspected the tunnel as it travelled toward H-Canyon. The team turned the RC around when it was about 20 feet from the H-Canyon crossover tunnel. From that point, the team drove the RC past the manway towards the new sand filter and stopped approximately 20 feet from the new sand filter. The team removed the RC from the tunnel, decontaminated the RC, and stored it the manway building, 294-2H. The RC deployment confirmed the IC was not in a condition to perform useful tunnel inspections and

  19. Crawler-Transporter Time-Lapse

    NASA Video Gallery

    Time-lapse video shows crawler-transporter No. 2 traveling from the Vehicle Assembly Building to Launch Pad 39A at NASA's Kennedy Space Center in Florida. The move was performed by the Ground Syste...

  20. Tractor beams for optical micromanipulation

    NASA Astrophysics Data System (ADS)

    Yevick, Aaron; Grier, David G.

    2016-03-01

    Tractor beams are traveling waves that transport illuminated objects in the retrograde direction relative to the direction of propagation. The theory of photokinetic effects identifies design criteria for long-range general- purpose tractor beams. These criteria distinguish first-order tractor beams that couple to induced dipole moments from higher-order tractor beams that rely on coupling to higher-order multipole moments to achieve pulling. First-order tractor beams are inherently longer-ranged and operate on a wider variety of materials. We explore the physics of first-order tractor beams in the context of a family of generalized solenoidal waves.

  1. Tractor Operation and Daily Care.

    ERIC Educational Resources Information Center

    Fore, J. M.; And Others

    Written for the tractor operator, the manual describes, with the aid of colored illustrations and diagrams, the tasks involved in the proper operation and daily maintenance of tractors. It offers explanations for the desirability of the various servicing and adjustment operations, as well as guidelines for tractor operation and safety. The…

  2. Tractor & Machinery Safety. 1984 Revision.

    ERIC Educational Resources Information Center

    Montana State Office of Public Instruction, Helena. Dept. of Vocational Education Services.

    This curriculum guide is intended for use in teaching an instructional unit in tractor and machinery safety that is geared toward college freshmen. Addressed in the individual lessons of the unit are the following topics: understanding the importance of safe and efficient tractor operation, understanding the characteristics of tractors, preparing…

  3. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05761, Marion Power Shovel Company, October 1963. CRAWLER TRUCK ASSEMBLY-FIELD WELDMENT SECTIONS & DETAILS. Sheet 4 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  4. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05761, Marion Power Shovel Company, October 1963. CRAWLER TRUCK ASSEMBLY-SIDE VIEW. Sheet 3 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  5. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05761, Marion Power Shovel Company, October 1963. CRAWLER TRUCK ASSEMBLY-PLAN VIEW. Sheet 2 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  6. Aerial view of the KSC crawler transporters

    NASA Technical Reports Server (NTRS)

    1998-01-01

    In this aerial view the Crawler Transporter Maintenance Building (center) sits between two crawler transporters. The KSC crawlers are the largest tracked vehicles known. Once used to move assembled Apollo/Saturn from the VAB to the launch pad, they are now used for transporting Shuttle vehicles. They move the Mobile Launcher Platform into the Vehicle Assembly Building and then to the Launch Pad with an assembled space vehicle. Maximum speed is 1.6 km (one mile) per hour loaded, about 3.2 km (2 miles) per hour unloaded. Launch Pad to VAB trip time with the Mobile Launch Platform is about 5 hours. The crawler burns 568 liters (150 gallons) of diesel oil per mile. KSC's two crawlers have accumulated 1,243 miles since 1977. Including the Apollo years, the transporters have racked up 2,526 miles, about the same distance as a one-way trip from KSC to Los Angeles by interstate highway or a round trip between KSC and New York City.

  7. Acoustic tractor beam.

    PubMed

    Démoré, Christine E M; Dahl, Patrick M; Yang, Zhengyi; Glynne-Jones, Peter; Melzer, Andreas; Cochran, Sandy; MacDonald, Michael P; Spalding, Gabriel C

    2014-05-01

    Negative radiation forces act opposite to the direction of propagation, or net momentum, of a beam but have previously been challenging to definitively demonstrate. We report an experimental acoustic tractor beam generated by an ultrasonic array operating on macroscopic targets (>1 cm) to demonstrate the negative radiation forces and to map out regimes over which they dominate, which we compare to simulations. The result and the geometrically simple configuration show that the effect is due to nonconservative forces, produced by redirection of a momentum flux from the angled sides of a target and not by conservative forces from a potential energy gradient. Use of a simple acoustic setup provides an easily understood illustration of the negative radiation pressure concept for tractor beams and demonstrates continuous attraction towards the source, against a net momentum flux in the system. PMID:24836252

  8. Acoustic Tractor Beam

    NASA Astrophysics Data System (ADS)

    Démoré, Christine E. M.; Dahl, Patrick M.; Yang, Zhengyi; Glynne-Jones, Peter; Melzer, Andreas; Cochran, Sandy; MacDonald, Michael P.; Spalding, Gabriel C.

    2014-05-01

    Negative radiation forces act opposite to the direction of propagation, or net momentum, of a beam but have previously been challenging to definitively demonstrate. We report an experimental acoustic tractor beam generated by an ultrasonic array operating on macroscopic targets (>1 cm) to demonstrate the negative radiation forces and to map out regimes over which they dominate, which we compare to simulations. The result and the geometrically simple configuration show that the effect is due to nonconservative forces, produced by redirection of a momentum flux from the angled sides of a target and not by conservative forces from a potential energy gradient. Use of a simple acoustic setup provides an easily understood illustration of the negative radiation pressure concept for tractor beams and demonstrates continuous attraction towards the source, against a net momentum flux in the system.

  9. Vegetable oils for tractors

    SciTech Connect

    Moroney, M.

    1981-11-14

    Preliminary tests by the Agricultural Institute, show that tractors can be run on a 50:50 rape oil-diesel mixture or on pure rape oil. In fact, engine power actually increased slightly with the 50:50 blend but decreased fractionally with pure rape oil. Research at the North Dakota State University on using sunflower oil as an alternative to diesel fuel is also noted.

  10. Tractor Safety. Unit A-9.

    ERIC Educational Resources Information Center

    Luft, Vernon D.; Backlund, Paul

    This document is a teacher's guide for a unit in tractor and machinery safety for college freshmen. It is intended to be used for 10 hours of instruction for freshmen who are intending to work on or around machinery. Safety hazards directly and indirectly related to many types of machinery are covered in addition to tractors. The objectives of the…

  11. Space Shuttle Crawler Transporter Sound Attenuation Study

    NASA Technical Reports Server (NTRS)

    Margasahayam, Ravi N.; MacDonald, Rod; Faszer, Clifford

    2004-01-01

    The crawler transporter (CT) is the world's largest tracked vehicle known, weighing 6 million pounds with a length of 131 feet and a width of 113 feet. The Kennedy Space Center (KSC) has two CTs that were designed and built for the Apollo program in the 1960's, maintained and retrofitted for use in the Space Shuttle program. As a key element of the Space Shuttle ground systems, the crawler transports the entire 12-million-pound stack comprising the orbiter, the mobile launch platform (MLP), the external tank (ET), and the solid rocket boosters (SRB) from the Vehicle Assembly Building (VAB) to the launch pad. This rollout, constituting a 3.5-5.0-mile journey at a top speed of 0.9 miles-per-hour, requires over 8 hours to reach either Launch Complex 39A or B. This activity is only a prelude to the spectacle of sound and fury of the Space Shuttle launch to orbit in less than 10 minutes and traveling at orbital velocities of Mach 24. This paper summarizes preliminary results from the Crawler Transporter Sound Attenuation Study, encompassing test and engineering analysis of significant sound sources to measure and record full frequency spectrum and intensity of the various noise sources and to analyze the conditions of vibration. Additionally, data such as ventilation criteria, plus operational procedures were considered to provide a comprehensive noise suppression design for implementation. To date, sound attenuation study and results on Crawler 2 have shown significant noise reductions ranging from 5 to 24 dBA.

  12. Dynamic acoustic tractor beams

    NASA Astrophysics Data System (ADS)

    Mitri, F. G.

    2015-03-01

    Pulling a sphere and vibrating it around an equilibrium position by amplitude-modulation in the near-field of a single finite circular piston transducer is theoretically demonstrated. Conditions are found where a fluid hexane sphere (with arbitrary radius) chosen as an example, centered on the axis of progressive propagating waves and submerged in non-viscous water, experiences an attractive (steady) force pulling it towards the transducer, as well as an oscillatory force forcing it to vibrate back-and-forth. Numerical predictions for the dynamic force illustrate the theory and suggest an innovative method in designing dynamic acoustical tractor beams.

  13. Dynamic acoustic tractor beams

    SciTech Connect

    Mitri, F. G.

    2015-03-07

    Pulling a sphere and vibrating it around an equilibrium position by amplitude-modulation in the near-field of a single finite circular piston transducer is theoretically demonstrated. Conditions are found where a fluid hexane sphere (with arbitrary radius) chosen as an example, centered on the axis of progressive propagating waves and submerged in non-viscous water, experiences an attractive (steady) force pulling it towards the transducer, as well as an oscillatory force forcing it to vibrate back-and-forth. Numerical predictions for the dynamic force illustrate the theory and suggest an innovative method in designing dynamic acoustical tractor beams.

  14. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 79K00088, John F. Kennedy Space Center, November 1969. SYS FUNCTIONAL DRAWING. Sheet 5 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  15. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 79K00081, John F. Kennedy Space Center, December 1969. SYS FUNCTIONAL DRAWING. Sheet 3 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  16. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 79K00088, John F. Kennedy Space Center, November 1969. SYS FUNCTIONAL DRAWING. Sheet 6 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  17. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05760, KSC-Launch Support Equipment Engineering Division, January 1967. GENERAL ARRANGEMENT. Sheet 1 of 4 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  18. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05762, Marion Power Shovel Company, December 1964. CHASSIS STRUCTURE ASSEMBLY. Sheet 2 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  19. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05760, Marion Power Shovel Company, January 1965. GENERAL ARRANGEMENT. Sheet 3 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  20. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05770, Marion Power Shovel Company, February 1964. OPERATOR'S CAB ASSY. Sheet 1 of 1 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  1. Optimizing Crawler4j using MapReduce Programming Model

    NASA Astrophysics Data System (ADS)

    Siddesh, G. M.; Suresh, Kavya; Madhuri, K. Y.; Nijagal, Madhushree; Rakshitha, B. R.; Srinivasa, K. G.

    2016-08-01

    World wide web is a decentralized system that consists of a repository of information on the basis of web pages. These web pages act as a source of information or data in the present analytics world. Web crawlers are used for extracting useful information from web pages for different purposes. Firstly, it is used in web search engines where the web pages are indexed to form a corpus of information and allows the users to query on the web pages. Secondly, it is used for web archiving where the web pages are stored for later analysis phases. Thirdly, it can be used for web mining where the web pages are monitored for copyright purposes. The amount of information processed by the web crawler needs to be improved by using the capabilities of modern parallel processing technologies. In order to solve the problem of parallelism and the throughput of crawling this work proposes to optimize the Crawler4j using the Hadoop MapReduce programming model by parallelizing the processing of large input data. Crawler4j is a web crawler that retrieves useful information about the pages that it visits. The crawler Crawler4j coupled with data and computational parallelism of Hadoop MapReduce programming model improves the throughput and accuracy of web crawling. The experimental results demonstrate that the proposed solution achieves significant improvements with respect to performance and throughput. Hence the proposed approach intends to carve out a new methodology towards optimizing web crawling by achieving significant performance gain.

  2. Tractor accidents in Swedish traffic.

    PubMed

    Pinzke, Stefan; Nilsson, Kerstin; Lundqvist, Peter

    2012-01-01

    The objective of this study is to reach a better understanding of accidents on Swedish roads involving tractors and to suggest ways of preventing them. In an earlier study we analyzed police-reported fatal accidents and accidents that led to physical injuries from 1992 to 2005. During each year of this period, tractors were involved in 128 traffic accidents on average, an average of 7 people were killed, 44 sustained serious injuries, and 143 sustained slight injuries. The number of fatalities in these tractor accidents was about 1.3% of all deaths in traffic accidents in Sweden. Cars were most often involved in the tractor accidents (58%) and 15% were single vehicle accidents. The mean age of the tractor driver involved was 39.8 years and young drivers (15-24 years) were overrepresented (30%). We are now increasing the data collected with the years 2006-2010 in order to study the changes in the number of accidents. Special attention will be given to the younger drivers and to single vehicle accidents. Based on the results we aim to develop suggestions for reducing road accidents, e.g. including measures for making farm vehicles more visible and improvement of the training provided at driving schools. PMID:22317543

  3. DETAIL VIEW OF CONNECTOR FOR MATING TO THE CRAWLER TRANSPORTER ...

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

    DETAIL VIEW OF CONNECTOR FOR MATING TO THE CRAWLER TRANSPORTER - Cape Canaveral Air Force Station, Launch Complex 39, Mobile Launcher Platforms, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  4. Crawler Transporter Steering and Jel Systems

    NASA Technical Reports Server (NTRS)

    Davis, V. L.

    1975-01-01

    The transporter weighing 2.8 million kilograms (6.3 million pounds) was used to lift a 5.7-million-kilogram (12.6-million-pound) combination of mobile launcher and space vehicle, transfer this load approximately 5.6 kilometers (3.5 miles) from its point of assembly, negotiate curves of 152-meter (500-foot) mean radius, climb a 5-percent grade while maintaining the 122-meter (400-foot) structure in a vertical position within 10 minutes of arc, and smoothly position this huge structure to within plus or minus 5.1 centimeters (plus or minus 2 inches) on support pedestals at the launch pad. The crawler-transporter is described in detail.

  5. A spatial information crawler for OpenGIS WFS

    NASA Astrophysics Data System (ADS)

    Jiang, Jun; Yang, Chong-jun; Ren, Ying-chao

    2008-10-01

    The growth of the internet makes it non-trivial to search for the accuracy information efficiently. Topical crawler, which is aiming at a certain area, attracts more and more intention now because it can help people to find out what they need. Furthermore, with the OpenGIS WFS (Web Feature Service) Specification developed by OGC (Open GIS Consortium), much more geospatial data providers adopt this protocol to publish their data on the internet. In this case, a crawler which is aiming at the WFS servers can help people to find the geospatial data from WFS servers. In this paper, we propose a prototype system of a WFS crawler based on the OpenGIS WFS Specification. The crawler architecture, working principles, and detailed function of each component are introduced. This crawler is capable of discovering WFS servers dynamically, saving and updating the service contents of the servers. The data collect by the crawler can be supported to a geospatial data search engine as its data source.

  6. ROPS deficiency of gray-market tractors.

    PubMed

    Myers, M L; Purschwitz, M A

    2012-04-01

    Many used tractors that are imported from Japan are adding to the current national inventory in the U.S. and Canada of farm tractors that lack a rollover protective structure (ROPS). Gray-market tractors are built for use by the manufacturer for a certain country but are imported against the manufacture's wishes to a second country for use there, usually as a used tractor. Gray-market tractors may lack ROPS and seatbelts, depending on the date of manufacturer. The objective of this investigation is to describe the gray market for tractors imported from Japan into the U.S. and the policy implications regarding the hazards associated with these imports. Operator manuals and warning labels are typically not written in English. Foreign manufacturers that market tractors in the U.S. have established a variety of disincentives for the importation of gray-market tractors, including issuing warnings, not servicing or providing parts for these tractors, and banning their importation through actions by the U.S. International Trade Commission. Nonetheless, a U.S. market has developed that imports and provides services and parts for gray-market tractors, and some companies provide certified ROPS on the tractors that they sell. A product safety perspective and related policies are presented as an approach to ensuring that these imports are equipped with ROPS and seatbelts. PMID:22655522

  7. Tractor Transmissions. A Teaching Reference.

    ERIC Educational Resources Information Center

    American Association for Agricultural Engineering and Vocational Agriculture, Athens, GA.

    The manual was developed as a reference for teaching students about transmissions in farm tractors. The manual is divided into five sections: (1) transmission history, (2) gears and bearings in transmission, (3) sliding-gear transmissions, (4) planetary gearing, and (5) glossary. The working principles of the sliding-gear transmission, the most…

  8. Liquid crystal elastomer strips as soft crawlers

    NASA Astrophysics Data System (ADS)

    DeSimone, Antonio; Gidoni, Paolo; Noselli, Giovanni

    2015-11-01

    In this paper, we speculate on a possible application of Liquid Crystal Elastomers to the field of soft robotics. In particular, we study a concept for limbless locomotion that is amenable to miniaturisation. For this purpose, we formulate and solve the evolution equations for a strip of nematic elastomer, subject to directional frictional interactions with a flat solid substrate, and cyclically actuated by a spatially uniform, time-periodic stimulus (e.g., temperature change). The presence of frictional forces that are sensitive to the direction of sliding transforms reciprocal, 'breathing-like' deformations into directed forward motion. We derive formulas quantifying this motion in the case of distributed friction, by solving a differential inclusion for the displacement field. The simpler case of concentrated frictional interactions at the two ends of the strip is also solved, in order to provide a benchmark to compare the continuously distributed case with a finite-dimensional benchmark. We also provide explicit formulas for the axial force along the crawler body.

  9. INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS

    SciTech Connect

    J. Bruce Nestleroth

    2004-05-01

    Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. However, not all pipelines can be inspected with current systems that move inside the pipeline propelled by the product flow. Inspection platforms that crawl slowly inside a pipeline are being developed to maneuver past the physical barriers that limit inspection. Battelle is building innovative electromagnetic sensors for pipeline crawlers. The various sensor types will assess a wide range of pipeline anomalies including corrosion, mechanical damage, cracking and seam weld defects. An implementation of two electromagnetic sensors were designed and tested. A pulsed eddy current system that uses sensors to measure the decay of induced eddy currents to establish the wall thickness has excellent potential. The results of experiments are comparable with magnetic flux leakage detecting 10% metal loss steps following a monotonic increase in signal strength. A rotating permanent remote field eddy current exciter was designed and built to produce strong signal levels at the receiver and reduce power consumption. Midway through the development of each technology, both sensor systems have produced results that warrant further development.

  10. Microhole Drilling Tractor Technology Development

    SciTech Connect

    Western Well Tool

    2007-07-09

    In an effort to increase the U.S. energy reserves and lower costs for finding and retrieving oil, the USDOE created a solicitation to encourage industry to focus on means to operate in small diameter well-Microhole. Partially in response to this solicitation and because Western Well Tool's (WWT) corporate objective to develop small diameter coiled tubing drilling tractor, WWT responded to and was awarded a contract to design, prototype, shop test, and field demonstrate a Microhole Drilling Tractor (MDT). The benefit to the oil industry and the US consumer from the project is that with the MDT's ability to facilitate Coiled Tubing drilled wells to be 1000-3000 feet longer horizontally, US brown fields can be more efficiently exploited resulting in fewer wells, less environmental impact, greater and faster oil recovery, and lower drilling costs. Shortly after award of the contract, WWT was approached by a major oil company that strongly indicated that the specified size of a tractor of 3.0 inches diameter was inappropriate and that immediate applications for a 3.38-inch diameter tractor would substantially increase the usefulness of the tool to the oil industry. Based on this along with an understanding with the oil company to use the tractor in multiple field applications, WWT applied for and was granted a no-cost change-of-scope contract amendment to design, manufacture, assemble, shop test and field demonstrate a prototype a 3.38 inch diameter MDT. Utilizing existing WWT tractor technology and conforming to an industry developed specification for the tool, the Microhole Drilling Tractor was designed. Specific features of the MDT that increase it usefulness are: (1) Operation on differential pressure of the drilling fluid, (2) On-Off Capability, (3) Patented unique gripping elements (4) High strength and flexibility, (5) Compatibility to existing Coiled Tubing drilling equipment and operations. The ability to power the MDT with drilling fluid results in a highly

  11. Plane waves as tractor beams

    NASA Astrophysics Data System (ADS)

    Forgács, Péter; Lukács, Árpád; Romańczukiewicz, Tomasz

    2013-12-01

    It is shown that in a large class of systems, plane waves act as tractor beams: i.e., an incident plane wave can exert a pulling force on the scatterer. The underlying physical mechanism for the pulling force is due to the sufficiently strong scattering of the incoming wave into another mode carrying more momentum, in which case excess momentum is created behind the scatterer. This tractor beam or negative radiation pressure (NRP) effect, is found to be generic in systems with multiple scattering channels. In a birefringent medium, electromagnetic plane waves incident on a thin plate exert NRP of the same order of magnitude as optical radiation pressure, while in artificial dielectrics (metamaterials), the magnitude of NRP can even be macroscopic. In two dimensions, we study various scattering situations on vortices, and NRP is shown to occur by the scattering of heavy baryons into light leptons off cosmic strings, and by neutron scattering off vortices in the XY model.

  12. Conformal superalgebras via tractor calculus

    NASA Astrophysics Data System (ADS)

    Lischewski, Andree

    2015-01-01

    We use the manifestly conformally invariant description of a Lorentzian conformal structure in terms of a parabolic Cartan geometry in order to introduce a superalgebra structure on the space of twistor spinors and normal conformal vector fields formulated in purely algebraic terms on parallel sections in tractor bundles. Via a fixed metric in the conformal class, one reproduces a conformal superalgebra structure that has been considered in the literature before. The tractor approach, however, makes clear that the failure of this object to be a Lie superalgebra in certain cases is due to purely algebraic identities on the spinor module and to special properties of the conformal holonomy representation. Moreover, it naturally generalizes to higher signatures. This yields new formulas for constructing new twistor spinors and higher order normal conformal Killing forms out of existing ones, generalizing the well-known spinorial Lie derivative. Moreover, we derive restrictions on the possible dimension of the space of twistor spinors in any metric signature.

  13. Simplified overturn stability monitoring of agricultural tractors.

    PubMed

    Nichol, C I; Sommer, H J; Murphy, D J

    2005-02-01

    Agricultural tractors are the most common source of farm work fatalities in the U.S., with overturns the most common type of incident. For the year 2001, there were 15 tractor-related fatalities in Pennsylvania, 9 of which were due to tractor rollover. A new device using low-cost sensors and microcomputers was developed around a simplified mathematical model of an agricultural tractor to inform the operator of potential tractor instability. This device communicates the current rollover potential, along with a recent history of rollover potential, to the operator of the tractor via a simple bar-graph display. The device uses a single-chip accelerometer to sense the current rollover potential and a small microprocessor to analyze the accelerometer data, compensate for variations due to temperature, and then send this information to a visual display. The use of these low-cost "off the shelf" components enabled the fabrication of a very inexpensive sensor system. Because agricultural tractors have a long service life, it was important to make the device low cost and flexible. This could enable it to be sold as an aftermarket add-on for a variety of tractor models. The device is also capable of interfacing with newer on-board tractor systems via a CAN bus to make it more attractive to tractor manufacturers who may want to incorporate this device into new models. Work is continuing on the development of an improved display to inform the tractor operator of possible instability, including display ergonomic studies, investigation of threshold levels for alerting an operator of potential instability, and investigation into audible warning signals.

  14. INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS

    SciTech Connect

    J. Bruce Nestleroth

    2005-11-30

    Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. Battelle has completed the second year of work on a projected three-year development effort. In the first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. The second inspection methodology is based on rotating permanent magnets. The rotating exciter unit produces strong eddy currents in the pipe wall. At distances of a pipe diameter or more from the rotating exciter, the currents flow circumferentially. These circumferential currents are deflected by pipeline defects such as corrosion and axially aligned cracks. Simple sensors are used to detect the change in current densities in the pipe wall. The

  15. INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS

    SciTech Connect

    J. Bruce Nestleroth

    2004-11-05

    Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. The Applied Energy Systems Group at Battelle is concluding the first year of work on a projected three-year development effort. In this first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. This second semiannual report focuses on the development of a second inspection methodology, based on rotating permanent magnets. During this period, a rotating permanent magnet exciter was designed and built. The exciter unit produces strong eddy currents in the pipe wall. The tests have shown that at distances of a pipe diameter or more, the currents flow circumferentially, and that these circumferential

  16. 49 CFR 523.9 - Truck tractors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 6 2011-10-01 2011-10-01 false Truck tractors. 523.9 Section 523.9 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION... this part are considered as any truck tractor as defined in 49 CFR part 571 having a GVWR above...

  17. Workmen and Crawler Crane pouring roof slab and parapet wall ...

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

    Workmen and Crawler Crane pouring roof slab and parapet wall of building - looking northwest. Taken Nov. 15, 1929. 14th Naval District Photo Collection Item No. 7165 - U.S. Naval Base, Pearl Harbor, Exterior Cranes, Waterfront Crane Track System, Pearl City, Honolulu County, HI

  18. The Organization of Wariness of Heights in Experienced Crawlers

    ERIC Educational Resources Information Center

    Ueno, Mika; Uchiyama, Ichiro; Campos, Joseph J.; Dahl, Audun; Anderson, David I.

    2012-01-01

    Most infants with more than 6 weeks of crawling experience completely avoid the deep side of a visual cliff (Campos, Bertenthal, & Kermoian, 1992; Gibson & Walk, 1960). However, some experienced crawlers do move onto the transparent surface suspended several feet above the ground. An important question is whether these "nonavoiders" lack wariness…

  19. Comparative analysis into the tractor-trailer braking dynamics: tractor with single axle brakes, tractor with all wheel brakes

    NASA Astrophysics Data System (ADS)

    Nastasoiu, Mircea; Ispas, Nicolae

    2014-06-01

    The paper elaborates a mathematical model in order to conduct a study into the dynamics of tractor-trailer systems during braking. The braking dynamics is analyzed by considering two versions for the braking system: 1) braking applied on the rear axle and 2) braking applied on all four wheels. In both versions the trailer is braked on all wheels. The mathematical model enables us to determine and graphically illustrate the evolution of the following parameters: braking deceleration, braking speed and the distance traveled by the tractor during braking. The mathematical model elaborated is applied on a tractor-trailer system completing transportation works.

  20. INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS

    SciTech Connect

    J. Bruce Nestleroth; Richard J. Davis

    2005-05-23

    Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. The Applied Energy Systems Group at Battelle is in the second year of work on a projected three-year development effort. In the first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. The second inspection methodology is based on rotating permanent magnets. The rotating exciter unit produces strong eddy currents in the pipe wall. At distances of a pipe diameter or more from the rotating exciter, the currents flow circumferentially. These circumferential currents are deflected by pipeline defects such as corrosion and axially aligned cracks. Simple sensors are used to detect the change in current

  1. Innovative Electromagnetic Sensors for Pipeline Crawlers

    SciTech Connect

    J. Bruce Nestleroth

    2006-05-04

    Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. Battelle is in the final year on a projected three-year development effort. In the first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. The second inspection methodology is based on rotating permanent magnets. The rotating exciter unit produces strong eddy currents in the pipe wall. At distances of a pipe diameter or more from the rotating exciter, the currents flow circumferentially. These circumferential currents are deflected by pipeline defects such as corrosion and axially aligned cracks. Simple sensors are used to detect the change in current densities in the pipe wall. The second semiannual

  2. Making 'Tractor Beams' a Reality (Eventually)

    NASA Video Gallery

    Tractor beams -- the ability to trap and move objects using laser light -- are the stuff of science fiction, but a team of NASA scientists has won funding to study the concept for remotely capturin...

  3. Generating stable tractor beams with dielectric metasurfaces

    NASA Astrophysics Data System (ADS)

    Pfeiffer, Carl; Grbic, Anthony

    2015-03-01

    Propagation-invariant beams that pull objects towards a light source are commonly known as tractor beams. Here, an efficient, linearly polarized tractor beam with improved stability is introduced. The beam consists of a superposition of transverse-electric and transverse-magnetic polarized Bessel beams of orders m =+1 and m =-1 . It is shown that this beam can stably pull a wide range of dielectric microparticles arbitrarily long distances, independent of ambient conditions. Next, a straightforward method of generating these high-performance beams is proposed. A Si metasurface transforms an incident linearly polarized Gaussian beam into the desired tractor beam. Full-wave simulations demonstrate that it is possible for this simple geometry to pull a polystyrene sphere a distance equal to the nondiffracting range of the Bessel beam. The simplicity of the setup and the robust performance of the proposed tractor beam significantly enhance the ability to manipulate matter with light.

  4. Tractor beams in the Rayleigh limit

    NASA Astrophysics Data System (ADS)

    Yevick, Aaron; Ruffner, David B.; Grier, David G.

    2016-04-01

    A tractor beam is a traveling wave that transports illuminated objects back to its source, opposite to the wave's direction of propagation, along its entire length. The requisite retrograde force arises when an object scatters the wave's momentum density downstream into the direction of propagation and then recoils upstream by conservation of momentum. Achieving this condition imposes constraints on the structure of the wave, which we elucidate in the Rayleigh limit, when the wavelength exceeds the size of the object. Continuously propagation-invariant modes such as Bessel beams do not satisfy these conditions at dipole order in the multipole expansion and so cannot serve as general-purpose long-ranged tractor beams. Modes with discrete propagation invariance, however, can act as first-order tractor beams. We demonstrate this by introducing a class of minimal solenoidal waves together with a set of design criteria that distinguish tractor beams that pull objects from repulsor beams that push them.

  5. Keys to Successful Tractor Maintenance Units.

    ERIC Educational Resources Information Center

    Doerr, William A.

    1979-01-01

    To prevent problems with teaching plans, supplement class instruction, and stimulate use of the operator's manual, the teacher can use a series of leaflets. The first leaflet describes the activities and what is expected of the tractor operator's manual. (LRA)

  6. Analysis of tractor-related deaths.

    PubMed

    Erkol, Zerrin; Buken, Bora; Hekimoglu, Yavuz; Erkol, Hayri; Ince, Haluk; Erzengin, Omer Utku

    2013-01-01

    The aim of the study was to evaluate the properties of tractor-related death cases and discuss the precautions in order to prevent such events. For this aim, reports made between 2006 and 2009 by the First Specialty Board of Council of Forensic Medicine (FSBCFM), Turkey, were evaluated retrospectively. Forty-one tractor-related death cases were included in this study. Thirty-five (85.4%) of the cases were male. The mean age was 42.52 ± 25.1 (with a range between 1 and 84 years old). The average time interval between the incident and death was 13.76 ± 33.53 days (range: 0-176 days) and 20 (48.8%) cases died on the incident spot or during transportation to the hospital. Among the cases, 34.1% (n = 14) were drivers, whereas 39.0% (n = 16) were passengers and the remaining were pedestrians (26.9%, n = 11). The accident was caused by the tractor rolling over in 34.1%, the victim being run over in 22.0%, and the victim falling from the tractor or trailer in 22.0% of the cases. Most of the events (56.1%) occurred on the road. In conclusion, tractors must not be used as a transportation vehicle for passengers. Periodic training of drivers can be useful for reducing tractor-related accidents. PMID:23540299

  7. Operator assessment of tractor roll angle with and without a tractor stability visual feedback device.

    PubMed

    Tillapaugh, J A; Murphy, D J; Sommer, H J; Garvey, P M

    2010-10-01

    According to a 2004 National Institute for Occupational Safety and Health (NIOSH) report, approximately 250 to 350 fatalities occur each year due to incidents involving production agriculture workers and tractors. Tractor overturns account for about 150 to 200 of these deaths. The goals of this project were to study operators' understanding of tractor roll angles and test a device to effectively deliver stability information to the tractor operator. This project required the design and construction of a full-scale tractor cab roll simulator that was used to identify lateral roll angles at which volunteer participants felt uncomfortable, as well as lateral roll angles at which they would no longer operate a tractor. In addition, the participants performed a series of tasks to test the functionality of a visual slope indicator that was designed to help them estimate slope angles. The project tested 231 tractor operators' perceptions of safe operation on side slopes and 128 participants' interactions with the visual slope indicator. Testing showed that the visual slope indicator was able to influence the angle estimations of the novice tractor operator population and helped the entire population of participants more accurately rank the simulator scenarios.

  8. Lube rack of Automotive and Tractor Repair Shops with Warehousefield ...

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

    Lube rack of Automotive and Tractor Repair Shops with Warehouse-field Equipment Repair Shop Building's wall to the right, looking from the south - Kekaha Sugar Company, Automotive and Tractor Repair Shops, 8315 Kekaha Road, Kekaha, Kauai County, HI

  9. View of south elevation of Automotive and Tractor Repair Shops ...

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

    View of south elevation of Automotive and Tractor Repair Shops with the Warehouse Fabrication Shop and Stack in the background, looking from the southwest - Kekaha Sugar Company, Automotive and Tractor Repair Shops, 8315 Kekaha Road, Kekaha, Kauai County, HI

  10. Miniature Tractor Pull Helps Teach Mechanical Power Transmission.

    ERIC Educational Resources Information Center

    Waggoner, Todd C.

    1996-01-01

    A miniature tractor pull was developed as a high school activity, enabling students to assess a tractor's pulling capabilities and determine subsequent horsepower. The activity takes the textbook concept of horsepower and makes it come alive. (JOW)

  11. North and east elevations of tractor shed facing southwest ...

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

    North and east elevations of tractor shed facing southwest - Norris Farm, Tractor Shed-Combine Barn, .5 mile west of County Road 857 & .25 mile east of County Road 88/1, Cheat Neck, Monongalia County, WV

  12. South and west elevations of tractor shed facing northeast ...

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

    South and west elevations of tractor shed facing northeast - Norris Farm, Tractor Shed-Combine Barn, .5 mile west of County Road 857 & .25 mile east of County Road 88/1, Cheat Neck, Monongalia County, WV

  13. 78 FR 36572 - Certain Crawler Cranes and Components Thereof Notice of Receipt of Complaint; Solicitation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-18

    ... COMMISSION Certain Crawler Cranes and Components Thereof Notice of Receipt of Complaint; Solicitation of... entitled Certain Crawler Cranes and Components Thereof, DN 2960; the Commission is soliciting comments on... Commission's Rules of Practice and Procedure filed on behalf of Manitowoc Cranes, LLC on June 12, 2013....

  14. 78 FR 69448 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Crawler...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ..., 2013, (78 FR 33860). Interested parties are encouraged to send comments to the OMB, Office of...; Crawler, Locomotive, and Truck Cranes Standard ACTION: Notice. SUMMARY: The Department of Labor (DOL) is... (ICR) titled, ``Crawler, Locomotive, and Truck Cranes Standard,'' to the Office of Management...

  15. 30 CFR 77.409 - Shovels, draglines, and tractors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shovels, draglines, and tractors. 77.409... COAL MINES Safeguards for Mechanical Equipment § 77.409 Shovels, draglines, and tractors. (a) Shovels, draglines, and tractors shall not be operated in the presence of any person exposed to a hazard from...

  16. Effectiveness of the Indiana 4-H Tractor Program: Alumni Perceptions.

    ERIC Educational Resources Information Center

    Carrabba, James J., Jr.; Talbert, B. Allen; Field, William E.; Tormoehlen, Roger

    2001-01-01

    Responses from Indiana 4-H tractor driving contestants 1982-197 (n=139) showed that 74% were employed on farms; most felt the contests effectively taught tractor safety and made them generally aware of safety. However, many still engaged in risky behaviors such as not wearing seatbelts in tractors with rollover protective structures or allowing…

  17. Tractor Mechanics: Learning Activity Packages 1-19.

    ERIC Educational Resources Information Center

    Clemson Univ., SC. Vocational Education Media Center.

    Learning activity packages are presented for teaching tractor mechanics. The first of two sections deals with miscellaneous tasks and contains learning activity packages on cleaning the tractor and receiving new tractor parts. Section 2 is concerned with maintaining and servicing the electrical system, and it includes the following learning…

  18. Tractor Mechanic--Teacher's Guide. Competency Based Education Curriculum.

    ERIC Educational Resources Information Center

    McCann, Edward W.

    This teacher's guide is designed to accompany the Tractor Mechanic Competency Based Education (CBE) Curriculum (CE 022 480). The following information is included: a discussion of the uses of the Tractor Mechanic CBE curriculum; definitions of related terms; the table of contents for the Tractor Mechanic CBE curriculum; a list of competencies by…

  19. The Tractor Electrical System. A Teaching Reference.

    ERIC Educational Resources Information Center

    American Association for Vocational Instructional Materials, Athens, GA.

    The fundamental principles underlying the application of electricity to tractors and farm equipment are presented. An understanding of the material in the basic manual will enable the service man to understand better the service procedures covered in service manuals on electrical equipment. Topics dealt with are fundamentals of electricity,…

  20. Tractor Trailer Driver's Training Programs. Performance Report.

    ERIC Educational Resources Information Center

    New Hampshire Vocational Technical Coll., Nashua.

    This document describes a project to develop a 320-hour tractor trailer driver training program and a 20-hour commercial driver licensing upgrade training program. Of 34 graduates from the training program, 28 secured employment in the trucking industry. From August 1989 to June 1990, 725 students were trained in the upgrade training program with…

  1. Polyhedron tracking and gravity tractor asteroid deflection

    NASA Astrophysics Data System (ADS)

    Ummen, N.; Lappas, V.

    2014-11-01

    In the wake of the Chelyabinsk airburst, the defense against hazardous asteroids is becoming a topic of high interest. This work improves the gravity tractor asteroid deflection approach by tracking realistic small body shapes with tilted ion engines. An algorithm for polyhedron tracking was evaluated in a fictitious impact scenario. The simulations suggest a capability increase up to 38.2% with such improved tilting strategies. The long- and short-term effects within polyhedron tracking are illustrated. In particular, the orbital reorientation effect is influential when realistic asteroid shapes and rotations are accounted for. Also analyzed is the subject of altitude profiles, a way to tailor the gravity tractor performance, and to achieve a steering ability within the B-plane. A novel analytical solution for the classic gravity tractor is derived. It removes the simulation need for classic tractor designs to obtain comparable two body model Δv figures. This paper corroborates that the asteroid shape can be exploited for maximum performance. Even a single engine tilt adjustment at the beginning of deflection operations yields more deflection than a fixed preset tilt.

  2. Extra-safe tractor-trailer coupling

    NASA Technical Reports Server (NTRS)

    Albrecht, W. P.; Sparks, R. H.

    1979-01-01

    Built-in safety mechanism for tractor-trailer "fifth-wheel" coupling keeps rig together in case kingpin failure. Modified coupling utilizes all standard components, such as two wear plates, kingpin, and kingpin latch. It is modified by adding semicircular lip to top wear plate, matching semicircular slot to bottom wear plate, and two latching stop mechanisms.

  3. Plans for Learning Stations. Tractor Mechanics.

    ERIC Educational Resources Information Center

    Clemson Univ., SC. Vocational Education Media Center.

    This shop guide gives graphic illustration of twenty-eight learning stations in a tractor mechanics shop, at each of which a specific learning activity occurs. The authors suggest that each station (most of them constructed of plywood or sheet metal and angle iron) be self-contained, having its own appropriate tools, supplies, parts, and set of…

  4. V-TECS Guide for Tractor Mechanic.

    ERIC Educational Resources Information Center

    Benson, Robert T.

    This guide contains a course outline for a tractor mechanic course. The outline is organized by 15 duties: performing general skills and maintaining and servicing storage battery, ignition circuit, the cooling system, the charging circuit, the starting circuit, gasoline fuel system, diesel fuel system, basic engine, lubrication system, clutches,…

  5. Tractor Mechanic Check Sheets for Modules.

    ERIC Educational Resources Information Center

    Clemson Univ., SC. Vocational Education Media Center.

    Forms for student self-checks and the instructor's final checklist (student evaluation) are provided for use with thirty-three learning modules on maintaining and servicing fuel and electrical systems in tractor mechanics. The student self-check asks the students questions about their understanding of the modules' content. The instructor's…

  6. Tractor beam in micro-scale

    NASA Astrophysics Data System (ADS)

    Brzobohatý, O.; Karásek, V.; Šiler, M.; Chvátal, L.; Čižmár, T.; Zemánek, P.

    2014-12-01

    Following the Keplerian idea of radiative forces one would intuitively expect that an object illuminated by sunlight radiation or a laser beam is accelerated along the direction of the photon flow. Such radiation pressure forms the basis for the concept of solar sail, or laser acceleration of micro-particles. In contrast, a hypothetical optical field known from the realm of science-fiction as the "tractor" beam attracts the matter from large distances against the beam propagation. We present a geometry of such"tractor" beam in micro-scale and experimentally demonstrate how it acts upon spherical micro-particles of various sizes or optically self-arranged structures of micro-particles.

  7. Drug use by tractor-trailer drivers.

    PubMed

    Lund, A K; Preusser, D F; Blomberg, R D; Williams, A F

    1988-05-01

    Blood or urine samples or both were obtained from 317 of 359 randomly selected tractor-trailer drivers asked to participate in a driver health survey conducted at a truck weighing station on Interstate 40 in Tennessee. Altogether, 29% of the drivers had evidence of alcohol, marijuana, cocaine, prescription or nonprescription stimulants, or some combination of these, in either blood or urine. Cannabinoids were found in 15% of the drivers' blood or urine; nonprescription stimulants such as phenylpropanolamine were found in 12%; prescription stimulants such as amphetamine were found in 5%; cocaine metabolites were found in 2%; and alcohol was found in less than 1%. These results provide the first objective information about the use of potentially abusive drugs by tractor-trailer drivers. The extent of driver impairment attributable to the observed drugs is uncertain because of the complex relationship between performance and drug concentrations.

  8. Electrostatic Tractor Analysis for GEO Debris Remediation

    NASA Astrophysics Data System (ADS)

    Hogan, Erik A.

    The high value of operating in the geostationary ring, coupled with increasing numbers of orbital debris, highlights the need for GEO debris remediation techniques. One recent proposed technique for GEO debris mitigation is the electrostatic tractor. Here, a tug vehicle approaches a target debris object and emits a focused electron beam onto it. This results in a negative charge on the debris, and a positive charge on the tug vehicle. Due to the near proximity of the highly charged objects (20 meters or less) an attractive electrostatic force on the order of milliNewtons results. This electrostatic force is used in conjunction with low thrusting by the tug vehicle to tow the debris object into a disposal orbit 200-300 kilometers above the GEO belt. During the tugging period, the charged relative motion between tug and deputy is stabilized through a feedback control law. This is accomplished using a novel relative motion description that isolates separation distance from the relative orientation. The equations of motion for the relative motion description are derived from the Clohessy-Wiltshire equations, assuming the debris object is in a nearly circular orbit. Lyapunov stability theory is used to derive an asymptotically stable control law for the tug thrusters during the towing period. The control law requires an estimate of the electrostatic force magnitude, and the impacts of improperly modeled charging on control response are determined. If the electrostatic force is under-predicted too severely, a collision may result. A bound on the control gains is determined to prevent such a collision. Expected reorbiting performance levels achievable with the electrostatic tractor are computed. An open-loop analytical performance study is performed where variational equations are used to predict how much general orbital elements may be changed using the electrostatic tractor over one orbital period for a towed object at geosynchronous altitude. In contrast to earlier

  9. Farm Tractor Tune-Up and Service Specifications.

    ERIC Educational Resources Information Center

    Bryant, J. G.; And Others

    Tune-up and service specifications for 10 major tractor manufacturers are presented in the handbook. In addition, the following tables are included: (1) spark plug heat-range comparisons, (2) freezing protection, (3) pressures for farm tractor tires, (4) use of calcium chloride for liquid weighting, (5) comparisons of American Petroleum Institute…

  10. Agricultural Tractor Safety on Public Roads and Farms.

    ERIC Educational Resources Information Center

    Department of Transportation, Washington, DC.

    This study investigated the extent, causes, and means of preventing agricultural tractor accidents. The report includes an estimate of annual tractor-related deaths, an identification of the primary causes of such accidents with consideration of the major hazards causing death or injury, and recommendations or means for preventing the occurrence…

  11. MTR MAIN FLOOR. MTR TRACTOR IS IN CENTER OF VIEW ...

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

    MTR MAIN FLOOR. MTR TRACTOR IS IN CENTER OF VIEW AMIDST AN ACCUMULATION OF CLUTTER ON THE FLOOR. TRACTOR HAD ATTACHMENTS IN FRONT TO FACILITATE MOVING OF COFFINS. INL NEGATIVE NO. 56-3027. Jack L. Anderson, Photographer, 9/17/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  12. Development of a small high-thrust tractor rocket motor

    SciTech Connect

    Carr, C.E.; Oberlander, W.F.

    1986-01-01

    This paper summarizes the parachute extraction tractor rocket motor design and test efforts conducted during the Sandia ASW/SOW development program. The prime contractor was Sandia National Laboratories, Albuquerque, New Mexico; the tractor rocket motor subcontractor was Morton Thiokol, Inc., Elkton, Maryland.

  13. Perceptions of tilt angles of an agricultural tractor.

    PubMed

    Görücü, Serap; Cavallo, Eugenio; Murphy, Dennis

    2014-01-01

    A tractor stability simulator has been developed to help study tractor operators' perceptions of angles when the simulator is tilted to the side. The simulator is a trailer-mounted tractor cab equipped with hydraulic lift that can tilt the tractor cabin up to 30 degrees. This paper summarizes data from 82 participants who sat in the simulator while it was tilted. Demographic variables, estimates of tilt angles, and measured tilt angles were collected. The effects of age, gender, tractor driving experience, and frequency of operation on the estimated and measured tilt angles were analyzed. The results showed that about 50% of the participants reported estimations of side tilt angles within ±5 degrees of the actual angles, and nearly the same percentage overestimated the actual side tilt angles. Only a small percentage underestimated the angles. Older, more experienced, and male participants set higher limits on the actual angle at which they felt uncomfortable and would not drive. PMID:24417527

  14. Enhanced Gravity Tractor Technique for Planetary Defense

    NASA Technical Reports Server (NTRS)

    Mazanek, Daniel D.; Reeves, David M.; Hopkins, Joshua B.; Wade, Darren W.; Tantardini, Marco; Shen, Haijun

    2015-01-01

    Given sufficient warning time, Earth-impacting asteroids and comets can be deflected with a variety of different "slow push/pull" techniques. The gravity tractor is one technique that uses the gravitational attraction of a rendezvous spacecraft to the impactor and a low-thrust, high-efficiency propulsion system to provide a gradual velocity change and alter its trajectory. An innovation to this technique, known as the Enhanced Gravity Tractor (EGT), uses mass collected in-situ to augment the mass of the spacecraft, thereby greatly increasing the gravitational force between the objects. The collected material can be a single boulder, multiple boulders, regolith or a combination of different sources. The collected mass would likely range from tens to hundreds of metric tons depending on the size of the impactor and warning time available. Depending on the propulsion system's capability and the mass collected, the EGT approach can reduce the deflection times by a factor of 10 to 50 or more, thus reducing the deflection times of several decades to years or less and overcoming the main criticism of the traditional gravity tractor approach. Additionally, multiple spacecraft can orbit the target in formation to provide the necessary velocity change and further reduce the time needed by the EGT technique to divert hazardous asteroids and comets. The robotic segment of NASA's Asteroid Redirect Mission (ARM) will collect a multi-ton boulder from the surface of a large Near-Earth Asteroid (NEA) and will provide the first ever demonstration of the EGT technique and validate one method of collecting in-situ mass on an asteroid of hazardous size.

  15. 78 FR 51724 - California State Motor Vehicle Pollution Control Standards; Tractor-Trailer Greenhouse Gas...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ... AGENCY California State Motor Vehicle Pollution Control Standards; Tractor-Trailer Greenhouse Gas...: The California Air Resources Board (CARB) has notified EPA that it has adopted a tractor-trailer... new and in-use tractors that haul such trailers on California highways (HD Tractor-Trailer...

  16. 75 FR 20005 - Crawler, Locomotive, and Truck Cranes Standard; Extension of the Office of Management and Budget...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-16

    ... Paperwork Reduction Act of 1995 (44 U.S.C. 3506 et seq.) and Secretary of Labor's Order No. 5-2007 (72 FR... Occupational Safety and Health Administration Crawler, Locomotive, and Truck Cranes Standard; Extension of the... collection requirements contained in its Crawler, Locomotive, and Truck Cranes Standard (29 CFR...

  17. Farming tractor fatalities in Virginia: an 11-year retrospective review.

    PubMed

    Fulcher, James; Noller, Anna; Kay, Deborah

    2012-12-01

    This retrospective case review examines farm tractor-related deaths in the Commonwealth of Virginia for an 11-year period, from 1997 to 2007. This study compares decedent's demographic information, toxicology results, and medical histories.A vast majority of farm tractor-related deaths were male (98%) and white (91%). The average age was 60 years with most deaths occurring between the ages of 40 and 80 years. Ethanol use was observed in 9% of all cases with 7% of cases being more than 0.08% wt/vol ethanol, which is the legal limit in Virginia to operate a motor vehicle.The more mountainous, Western District Office of the Chief Medical Examiner composed 60% of total cases with 43% of these western cases related to tractor use on a natural slope or incline. The deaths in other districts were all less than 13% natural slope or incline related, reflecting the topography of these areas.These findings confirm much of what observation would suggest; accidents with farming tractors typically involve older white men. Operating a tractor on steep inclines is dangerous as many tractors do not have adequate rollover protection. The use of ethanol is dangerous when using any heavy equipment.This study provides an initial look at tractor-related deaths in Virginia, and more research is needed in this area to improve safety mechanisms on this machinery.

  18. A simple method to improve autonomous GPS positioning for tractors.

    PubMed

    Gomez-Gil, Jaime; Alonso-Garcia, Sergio; Gómez-Gil, Francisco Javier; Stombaugh, Tim

    2011-01-01

    Error is always present in the GPS guidance of a tractor along a desired trajectory. One way to reduce GPS guidance error is by improving the tractor positioning. The most commonly used ways to do this are either by employing more precise GPS receivers and differential corrections or by employing GPS together with some other local positioning systems such as electronic compasses or Inertial Navigation Systems (INS). However, both are complex and expensive solutions. In contrast, this article presents a simple and low cost method to improve tractor positioning when only a GPS receiver is used as the positioning sensor. The method is based on placing the GPS receiver ahead of the tractor, and on applying kinematic laws of tractor movement, or a geometric approximation, to obtain the midpoint position and orientation of the tractor rear axle more precisely. This precision improvement is produced by the fusion of the GPS data with tractor kinematic control laws. Our results reveal that the proposed method effectively reduces the guidance GPS error along a straight trajectory.

  19. A mathematical equation for quantifying control functionality in agricultural tractors.

    PubMed

    Drakopoulos, D; Mann, D D

    2008-10-01

    The overall accessibility of controls is one of the most important issues to consider when designing a control layout. Well-arranged controls, whose operational characteristics are based on both design guidelines and on human factors considerations, allow the operator to efficiently interact with the system in question. The objective of this article is to introduce a numerical index, referred to as the "index of functionality", capable of comparing, on a mathematical basis, different control arrangements in agricultural tractors. The model is based on information that has been gleaned from the published literature, with input from both professional ergonomists and experienced agricultural tractor operators. The numerical index may take any value between 0 and +1, with +1 being defined as an optimum value in terms of the functionality of a workstation. Data were collected from six old (pre-1982) and six modern (post-2003) tractor workstations to determine whether the model would recognize improvements that have occurred in the ergonomic design of tractor control layouts over the past 20 years. An average score of 0.19 +/- 0.07 was calculated for the pre-1982 tractor workstations. By contrast, an average score of 0.63 +/- 0.10 was calculated for the post-2003 tractor workstations. A number of limitations have been identified with the current model; despite these limitations, the index of functionality clearly recognized the ergonomic improvements in tractor workstations that have occurred over the past 20 years. PMID:19044167

  20. A Simple Method to Improve Autonomous GPS Positioning for Tractors

    PubMed Central

    Gomez-Gil, Jaime; Alonso-Garcia, Sergio; Gómez-Gil, Francisco Javier; Stombaugh, Tim

    2011-01-01

    Error is always present in the GPS guidance of a tractor along a desired trajectory. One way to reduce GPS guidance error is by improving the tractor positioning. The most commonly used ways to do this are either by employing more precise GPS receivers and differential corrections or by employing GPS together with some other local positioning systems such as electronic compasses or Inertial Navigation Systems (INS). However, both are complex and expensive solutions. In contrast, this article presents a simple and low cost method to improve tractor positioning when only a GPS receiver is used as the positioning sensor. The method is based on placing the GPS receiver ahead of the tractor, and on applying kinematic laws of tractor movement, or a geometric approximation, to obtain the midpoint position and orientation of the tractor rear axle more precisely. This precision improvement is produced by the fusion of the GPS data with tractor kinematic control laws. Our results reveal that the proposed method effectively reduces the guidance GPS error along a straight trajectory. PMID:22163917

  1. Tractor Mechanics. Maintaining and Servicing the Engine, Learning Activity Packages 78-89; Lubricating the Tractor, Learning Activity Packages 90-94; Painting the Tractor, Learning Activity Packages 95-96.

    ERIC Educational Resources Information Center

    Clemson Univ., SC. Vocational Education Media Center.

    This series of learning activity packages focuses on three areas of tractor mechanics: (1) maintaining and servicing the engine, (2) lubricating the tractor, and (3) painting the tractor. Each of the nineteen illustrated learning activity packages follows a typical format: introduction, directions, objectives, learning activities, tools and…

  2. Narrow-track wheeled agricultural tractor parameter variation.

    PubMed

    Guzzomi, A; Rondelli, V

    2013-10-01

    Despite a general consensus among farmers, manufacturers, and researchers that wheeled agricultural tractor design has changed over time, there is little published evidence. There is debate as to whether the standardized rollover protective structure (ROPS) energy and force requirements, based on a tractor reference mass and pertaining to studies conducted more than 40 years ago, are appropriate for modern tractors. This article investigated the physical parameters of 326 modern narrow-track tractors, measured according to OECD Code 6 over 16 years (1993 to 2008 inclusive): 252 (-77%) were fixed-chassis tractors and 74 (-23%) were articulated. To understand the significance of design changes, the data were analyzed with respect to time and as a function of tractor mass. Articulated and fixed-chassis data were treated separately. The time data allowed qualitative analysis, while the mass data allowed quantitative analysis. The parameters show some changes over time and clearly indicate differences between articulated and fixed-chassis types. The parameter changes, along with the differences between types, may have important safety ramifications for ROPS energy absorption requirements, and these aspects are discussed. Regression lines with R2 values were fitted to the mass-related data for fixed-chassis and articulated tractors to determine the suitability of fit. The mass relations also displayed differences between fixed-chassis and articulated tractors. Thus, the most significant recommendation from this study is that the standardized testing procedure for narrow-track wheeled agricultural tractor category should be split into two groups: fixed-chassis and articulated. PMID:24673034

  3. Risk analysis of tractor overturns on catfish farms.

    PubMed

    Stephens, Walter B; Ibendahl, Gregory A; Myers, Melvin L; Cole, Henry P

    2010-10-01

    Fatal and nonfatal injuries occur on catfish farms as a result of tractor overturns, but these injuries can be greatly mitigated when a tractor is equipped with a rollover protective structure (ROPS) and seatbelt. This study analyzed the proportion of tractors on catfish farms in Mississippi not equipped with ROPS and the cost of retrofitting those tractors with a ROPS and seatbelt as compared to the expected benefits gained from adding the protection. To determine if farmers have the financial incentive to retrofit older tractors, a net present value framework was used because the expected benefits occur over a number of years. The ROPS retrofit is a one-time cost that occurs immediately, and thus the present value does not need to be calculated, i.e., time period 0. According to this study adding ROPS will provide a net benefit of $22,877 in the event of an overturn. When dealing with small farms (<125 acres) where an average tractor is used for approximately twice as many hours compared to an average tractor on large farms, the extra hours worked by a single tractor resulted in total benefits of retrofitting ROPS of $9.45 per year, whereas for large farms the net benefit is $4.70 (=125 acres). Given that the least expensive retrofit is $147, it would take 15.5 years of tractor use on the small farms for the expected benefits to outweigh the cost. Given the large range of costs that could occur due to an overturn, there could be a significant premium for not having ROPS protection. In other words, there likely is a smaller range of costs from an overturn with ROPS than without ROPS because ROPS reduces the more serious incidents. PMID:20954036

  4. DETAIL VIEW OF STEAM TRACTOR "OLD DINAH," LOOKING NORTHWEST. THIS ...

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

    DETAIL VIEW OF STEAM TRACTOR "OLD DINAH," LOOKING NORTHWEST. THIS STEAM TRACTOR WAS USED TO REPLACE THE HORSE WAGON TRAINS THAT CARRIED SUPPLIES AND CRUDE OIL THE 26 MILES FROM BEATTY, NEVADA TO KEANE WONDER. THE TRACTOR ONLY MADE ONE RUN IN 1909 BEFORE THE BOILER EXPLODED ENROUTE, AND IT WAS ABANDONED THERE ON THE TRAIL TODAY IT STANDS ON DISPLAY AT THE FURNACE CREEK RANCH IN DEATH VALLEY NATIONAL PARK, AS SEEN IN THE PHOTOGRAPH. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  5. VIEW OF STACK WITH AUTOMOBILE AND TRACTOR REPAIR SHOP TO ...

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

    VIEW OF STACK WITH AUTOMOBILE AND TRACTOR REPAIR SHOP TO THE FAR RIGHT. WAREHOUSE WITH ITS RIDGELINE ROTARY VENTS TO RIGHT OF STACK. VIEW FROM THE WEST - Kekaha Sugar Company, Sugar Mill Building, 8315 Kekaha Road, Kekaha, Kauai County, HI

  6. Environmental perspective facing south showing chicken house, tractor shed, and ...

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

    Environmental perspective facing south showing chicken house, tractor shed, and homestead - Norris Farm, .5 mile west of County Road 857 & .25 mile east of County Road 88/1, Cheat Neck, Monongalia County, WV

  7. [Ergonomic evaluation of assembly line of tractors].

    PubMed

    Dellera, L; Buratti, G

    2012-01-01

    In the assembly lines in the engineering sector, ever more guided by the theories of lean production, is increasingly important ergonomic factor working conditions to preserve the health of workers and ensuring the performance. This analysis has focused on the study of biomechanical and postural stress of work tasks of an assembly line of the tractor, characterized by different weights and volumes from that of the car. Comparison with the technical standard of EN 1005-4 has allowed the identification as the machining assembly of small components result in conditions of acceptability, while most of the other processes aren't reliable. The emergence of these problems pushed to find several ergonomic solutions including the development of a special reclining seat to enable a proper posture during the working. PMID:23405593

  8. Schedule tightness among tractor-trailer drivers.

    PubMed

    Beilock, Richard

    2003-06-01

    The extent to which schedules are sufficiently tight to encourage violations of Hours-of-Service Regulations, speed limits, or both was investigated through a survey of over 1,600 tractor-trailer drivers. The focus was on drivers with refrigerated trailers. The results indicate high incidence levels of tight schedules. For example, assuming average speed limits of 65 mph, 24% had violation-inducing schedules with regard to the movement they were making at the time of the interviews. Incorporating information about previous driving, the incidence of violation-inducing schedules rose to 40%. Comparison with an earlier study suggests that, despite increases in speed limits which would tend to loosen schedules, schedules have become tighter over the past decade. The implications of these findings for reforms of Hours-of-Service Regulations are briefly discussed.

  9. 78 FR 42800 - Certain Crawler Cranes and Components Thereof; Institution of Investigation Pursuant to United...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-17

    ... certain crawler cranes and components thereof by reason of infringement of U.S. Patent No. 7,546,928 (``the '928 patent'') and U.S. Patent No. 7,967,158 (``the '158 patent''), and that an industry in the... one or more of claims 1, 2, and 5 of the '928 patent and claim 1 of the '158 patent, and whether...

  10. Design and experimental validation of a simple controller for a multi-segment magnetic crawler robot

    NASA Astrophysics Data System (ADS)

    Kelley, Leah; Ostovari, Saam; Burmeister, Aaron B.; Talke, Kurt A.; Pezeshkian, Narek; Rahimi, Amin; Hart, Abraham B.; Nguyen, Hoa G.

    2015-05-01

    A novel, multi-segmented magnetic crawler robot has been designed for ship hull inspection. In its simplest version, passive linkages that provide two degrees of relative motion connect front and rear driving modules, so the robot can twist and turn. This permits its navigation over surface discontinuities while maintaining its adhesion to the hull. During operation, the magnetic crawler receives forward and turning velocity commands from either a tele-operator or high-level, autonomous control computer. A low-level, embedded microcomputer handles the commands to the driving motors. This paper presents the development of a simple, low-level, leader-follower controller that permits the rear module to follow the front module. The kinematics and dynamics of the two-module magnetic crawler robot are described. The robot's geometry, kinematic constraints and the user-commanded velocities are used to calculate the desired instantaneous center of rotation and the corresponding central-linkage angle necessary for the back module to follow the front module when turning. The commands to the rear driving motors are determined by applying PID control on the error between the desired and measured linkage angle position. The controller is designed and tested using Matlab Simulink. It is then implemented and tested on an early two-module magnetic crawler prototype robot. Results of the simulations and experimental validation of the controller design are presented.

  11. The Influence of Tractor-Seat Height above the Ground on Lateral Vibrations

    PubMed Central

    Gomez-Gil, Jaime; Gomez-Gil, Francisco Javier; Martin-de-Leon, Rebeca

    2014-01-01

    Farmers experience whole-body vibrations when they drive tractors. Among the various factors that influence the vibrations to which the driver is exposed are terrain roughness, tractor speed, tire type and pressure, rear axle width, and tractor seat height above the ground. In this paper the influence of tractor seat height above the ground on the lateral vibrations to which the tractor driver is exposed is studied by means of a geometrical and an experimental analysis. Both analyses show that: (i) lateral vibrations experienced by a tractor driver increase linearly with tractor-seat height above the ground; (ii) lateral vibrations to which the tractor driver is exposed can equal or exceed vertical vibrations; (iii) in medium-size tractors, a feasible 30 cm reduction in the height of the tractor seat, which represents only 15% of its current height, will reduce the lateral vibrations by around 20%; and (iv) vertical vibrations are scarcely influenced by tractor-seat height above the ground. The results suggest that manufacturers could increase the comfort of tractors by lowering tractor-seat height above the ground, which will reduce lateral vibrations. PMID:25340448

  12. The influence of tractor-seat height above the ground on lateral vibrations.

    PubMed

    Gomez-Gil, Jaime; Gomez-Gil, Francisco Javier; Martin-de-Leon, Rebeca

    2014-01-01

    Farmers experience whole-body vibrations when they drive tractors. Among the various factors that influence the vibrations to which the driver is exposed are terrain roughness, tractor speed, tire type and pressure, rear axle width, and tractor seat height above the ground. In this paper the influence of tractor seat height above the ground on the lateral vibrations to which the tractor driver is exposed is studied by means of a geometrical and an experimental analysis. Both analyses show that: (i) lateral vibrations experienced by a tractor driver increase linearly with tractor-seat height above the ground; (ii) lateral vibrations to which the tractor driver is exposed can equal or exceed vertical vibrations; (iii) in medium-size tractors, a feasible 30 cm reduction in the height of the tractor seat, which represents only 15% of its current height, will reduce the lateral vibrations by around 20%; and (iv) vertical vibrations are scarcely influenced by tractor-seat height above the ground. The results suggest that manufacturers could increase the comfort of tractors by lowering tractor-seat height above the ground, which will reduce lateral vibrations. PMID:25340448

  13. Mission Designs for Demonstrating Gravity Tractor Asteroid Deflection

    NASA Astrophysics Data System (ADS)

    Busch, M.; Faber, N.; Eggl, S.; Morrison, D.; Clark, A.; Frost, C.; Jaroux, B. A.; Khetawat, V.

    2015-12-01

    Gravity tractor asteroid deflection relies on the gravitational attraction between the target and a nearby spacecraft; using low-thrust propulsion to change the target's trajectory slowly but continuously. Our team, based at the NASA Ames Mission Design Center, prepared designs for a Gravity Tractor Demonstration Mission (GTDM) for the European Commission's NEOShield initiative. We found five asteroids with well-known orbits and opportunities for efficient stand-alone demonstrations in the 2020s. We selected one object, 2000 FJ10, for a detailed design analysis. Our GTDM design has a 4 kW solar-electric propulsion system and launch mass of 1150 kg. For a nominal asteroid mass of 3 x 109 kg and diameter 150 m, and a hovering altitude 125 m above the asteroid's surface, GTDM would change FJ10's semi-major axis by 10 km over 2 years. To measure the deflection clearly and to permit safe hovering by the spacecraft, several months of survey and characterization are required prior to the active tractoring phase of the mission. Accurate tracking is also required after the tractoring phase, to ensure that the asteroid has indeed been deflected as intended. The GTDM design includes both spacecraft and Earth-based observations of FJ10 to verify the deflection. The estimated cost of GTDM is $280 million. Trajectory analysis for GTDM confirmed that the outcome of a deflection of any asteroid depends on when that deflection is performed. Compared to kinetic impactor deflection, the gradual deflection from a gravity tractor produces comparable results for a given total momentum transfer. However, a gravity tractor can have greater flexibility in the direction in which the target asteroid can be deflected. Asteroid deflection scenarios must be modeled carefully on a case-to-case basis. We will review implications of the results of the GTDM study to other proposed gravity tractor demonstrations, such as that included in NASA's Asteroid Redirect Mission.

  14. Ensuring Machine and Tractor Aggregates Operability

    NASA Astrophysics Data System (ADS)

    Redreev, G. V.

    2016-08-01

    the operability of the machine and tractor aggregates is ensured by processes which occur in machine units and considered as technical systems. In order to develop theoretical understanding of the processes in technical systems as the basis and purpose of the repairserving actions, the author's concept is presented which relies on on the basic concepts of "processes in technical systems", "maintenance and repair of performers", "maintenance and repair of technology" "objectives of the maintenance and repair". Analysis of the basic concepts of "processes in technical systems" made possible to distinguishing four types of relations: of order, stipulation, exactingness, and non-contradiction. It is shown that the implementation of maintenance and repair of technology should be conducted according to the assessment of the effectiveness of processes in technical systems, revealed in complex diagnosis. The perfection of the design of the machine in terms of its technical operation can be estimated according to the degree of consistency of processes in technical systems, purposes of maintenance and repair. In order to increase the efficiency of the lubrication system,the modernised design of the centrifugal oil filter with permanent control of its cleaning power is offered, which allows changing the technology of the maintenance of engine lubrication system by separating the operations of crankcase oil replacement and the rotor filter cleaning.

  15. 49 CFR 393.61 - Truck and truck tractor window construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Truck and truck tractor window construction. 393... REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.61 Truck and truck tractor window construction. Each truck and truck tractor (except trucks engaged in...

  16. 49 CFR 393.61 - Truck and truck tractor window construction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Truck and truck tractor window construction. 393... REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.61 Truck and truck tractor window construction. Each truck and truck tractor (except trucks engaged in...

  17. 49 CFR 393.61 - Truck and truck tractor window construction.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Truck and truck tractor window construction. 393... REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.61 Truck and truck tractor window construction. Each truck and truck tractor (except trucks engaged in...

  18. 49 CFR 393.61 - Truck and truck tractor window construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Truck and truck tractor window construction. 393... REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.61 Truck and truck tractor window construction. Each truck and truck tractor (except trucks engaged in...

  19. 49 CFR 393.61 - Truck and truck tractor window construction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Truck and truck tractor window construction. 393... REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.61 Truck and truck tractor window construction. Each truck and truck tractor (except trucks engaged in...

  20. 75 FR 2153 - Certificate of Alternative Compliance for the Tractor Tug FORTE

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-14

    ... SECURITY Coast Guard Certificate of Alternative Compliance for the Tractor Tug FORTE AGENCY: Coast Guard... was issued for the tractor tug FORTE as required by 33 U.S.C. 1605(c) and 33 CFR 81.18. DATES: The... Purpose The tractor tug FORTE will be used for offshore supply operations. The horizontal distance...

  1. 4-H Tractor Operator Program Teaches Employability Skills and Safety to Youth

    ERIC Educational Resources Information Center

    Barrett, Debra K.

    2013-01-01

    For Michigan State University Extension, the Berrien County 4-H Tractor Operator Program has provided tractor safety education to teens for over 30 years. The certification training satisfies current requirements for operation of a 20 PTO HP or greater agricultural tractor by 14- and 15-year-old youth employed on property "not" owned,…

  2. Creating a National Coalition to Address Tractor Overturn Fatalities.

    PubMed

    Tinc, P J; Ayers, P D; May, J J; Purschwitz, M A; Sorensen, J A

    2015-04-01

    Tractor overturns continue to be the leading cause of death on U.S. farms. While rollover protective structures (ROPS) are effective in preventing these fatalities, they are underutilized due to a number of barriers. Past programs in the U.S. and abroad have targeted this area of agricultural safety; however, a national program is not yet in place for U.S. farmers. This study seeks to build a national partnership to address tractor overturn fatalities by increasing the number of tractors with ROPS. A diverse, multisector steering committee has been organized and is working together using Whole System in a Room methods. This method brings together partners from nine stakeholder groups to identify and commit to a collaborative solution to the issue. PMID:26204786

  3. Tractor controls actuating force limits for Indian operators.

    PubMed

    Mehta, C R; Pandey, M M; Tiwari, P S; Gite, L P; Khadatkar, Abhijit

    2011-01-01

    In four-wheel tractors, proper design of controls is important for comfortable and safe operation of the tractor. The design involves location and dimensions of controls as well as strength limits for operating these controls. The present study was aimed to quantify human strength for operation of tractor controls and to recommend the maximum control actuating forces for normal operation of tractors based on strength capability of 3,423 Indian male agricultural workers. The 5th percentile values of strength parameters i.e. leg strength sitting (left and right), foot strength sitting (right), torque strength (both hands) sitting, push strength (left hand and right hand) sitting and pull strength (left hand and right hand) sitting of agricultural workers collected using a strength measurement set-up were taken into consideration for the study. It was recommended that the maximum actuating forces for normal operation of frequently operated brake and clutch pedals of tractors should not exceed 260 N and 125 N based on 5th percentile values of right and left leg strength of male agricultural workers, respectively. The maximum actuating force required in steering wheel operation should not exceed 51 N based on 5th percentile value of torque strength (both hands) sitting of workers. The maximum actuating forces required for operating frequently operated levers viz. gear selection, speed selection, hydraulic control and hand throttle of Indian tractors should not exceed 46 N, 46 N, 25 N and 25 N, respectively. It may be concluded that the maximum actuating force limits as given in Bureau of Indian Standards IS 10703 are very high as compared to the findings of the study based on strength data of Indian male operators, which highlight the need to revise the standard. PMID:21697615

  4. Innovative Sensors for Pipeline Crawlers: Rotating Permanent Magnet Inspection

    SciTech Connect

    J. Bruce Nestleroth; Richard J. Davis; Stephanie Flamberg

    2006-09-30

    Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they may encounter. To facilitate inspection of these ''unpiggable'' pipelines, recent inspection development efforts have focused on a new generation of powered inspection platforms that are able to crawl slowly inside a pipeline and can maneuver past the physical barriers that limit internal inspection applicability, such as bore restrictions, low product flow rate, and low pressure. The first step in this research was to review existing inspection technologies for applicability and compatibility with crawler systems. Most existing inspection technologies, including magnetic flux leakage and ultrasonic methods, had significant implementation limitations including mass, physical size, inspection energy coupling requirements and technology maturity. The remote field technique was the most promising but power consumption was high and anomaly signals were low requiring sensitive detectors and electronics. After reviewing each inspection technology, it was decided to investigate the potential for a new inspection method. The new inspection method takes advantage of advances in permanent magnet strength, along with their wide availability and low cost. Called rotating permanent magnet inspection (RPMI), this patent pending technology employs pairs of permanent magnets rotating around the central axis of a cylinder to induce high current densities in the material under inspection. Anomalies and wall thickness variations are detected with an array of sensors that measure local changes in the magnetic field produced by the induced current flowing in the material. This inspection method is an alternative to the common concentric coil remote field technique that induces low-frequency eddy

  5. Mission Concepts and Operations for Asteroid Mitigation Involving Multiple Gravity Tractors

    NASA Technical Reports Server (NTRS)

    Foster, Cyrus; Bellerose, Julie; Jaroux, Belgacem; Mauro, David

    2012-01-01

    The gravity tractor concept is a proposed method to deflect an imminent asteroid impact through gravitational tugging over a time scale of years. In this study, we present mission scenarios and operational considerations for asteroid mitigation efforts involving multiple gravity tractors. We quantify the deflection performance improvement provided by a multiple gravity tractor campaign and assess its sensitivity to staggered launches. We next explore several proximity operation strategies to accommodate multiple gravity tractors at a single asteroid including formation-flying and mechanically-docked configurations. Finally, we utilize 99942 Apophis as an illustrative example to assess the performance of a multiple gravity tractor campaign.

  6. The rod of Aesculapios: John Haygarth (1740-1827) and Perkins' metallic tractors.

    PubMed

    Booth, Christopher

    2005-08-01

    James Gillray's cartoon Metallic Tractors, published in 1801, portrays Benjamin Perkins treating a boil on the nose of an alcoholic John Bull with a pair of metallic tractors. The tractors had been invented by his father, Elisha Perkins of Connecticut, and were supposed to relieve pain and other symptoms through the agency of animal magnetism. The tractors were revealed as nothing more than an expensive sham by Dr John Haygarth in Bath, who showed that wooden tractors were equally effective. Thus, he was one of the first to use a placebo in a single-blind clinical trial.

  7. A spatial cluster analysis of tractor overturns in Kentucky from 1960 to 2002

    USGS Publications Warehouse

    Saman, D.M.; Cole, H.P.; Odoi, A.; Myers, M.L.; Carey, D.I.; Westneat, S.C.

    2012-01-01

    Background: Agricultural tractor overturns without rollover protective structures are the leading cause of farm fatalities in the United States. To our knowledge, no studies have incorporated the spatial scan statistic in identifying high-risk areas for tractor overturns. The aim of this study was to determine whether tractor overturns cluster in certain parts of Kentucky and identify factors associated with tractor overturns. Methods: A spatial statistical analysis using Kulldorff's spatial scan statistic was performed to identify county clusters at greatest risk for tractor overturns. A regression analysis was then performed to identify factors associated with tractor overturns. Results: The spatial analysis revealed a cluster of higher than expected tractor overturns in four counties in northern Kentucky (RR = 2.55) and 10 counties in eastern Kentucky (RR = 1.97). Higher rates of tractor overturns were associated with steeper average percent slope of pasture land by county (p = 0.0002) and a greater percent of total tractors with less than 40 horsepower by county (p<0.0001). Conclusions: This study reveals that geographic hotspots of tractor overturns exist in Kentucky and identifies factors associated with overturns. This study provides policymakers a guide to targeted county-level interventions (e.g., roll-over protective structures promotion interventions) with the intention of reducing tractor overturns in the highest risk counties in Kentucky. ?? 2012 Saman et al.

  8. 40 CFR 1037.630 - Special purpose tractors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Special purpose tractors. 1037.630 Section 1037.630 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Special Compliance Provisions §...

  9. 40 CFR 1037.630 - Special purpose tractors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... under § 1037.135: “THIS VEHICLE WAS CERTIFIED AS A VOCATIONAL TRACTOR UNDER 40 CFR 1037.630.”. (4) You... § 1037.631 and using an engine certified to the standards of 40 CFR part 1036 are deemed to fully conform... Section 1037.630 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

  10. 40 CFR 1037.630 - Special purpose tractors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... under § 1037.135: “THIS VEHICLE WAS CERTIFIED AS A VOCATIONAL TRACTOR UNDER 40 CFR 1037.630.”. (4) You... § 1037.631 and using an engine certified to the standards of 40 CFR part 1036 are deemed to fully conform... Section 1037.630 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

  11. Math on the Job. Tractor-Trailer Driver.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This booklet is intended to help mainstreamed mentally retarded, emotionally disturbed, or learning disabled high school students acquire a basic understanding of the responsibilities and working conditions of tractor-trailer drivers and to practice basic math skills necessary in the occupation. The first section provides a brief introduction to…

  12. Tractor Mechanic--Student Material. Competency Based Education Curriculum.

    ERIC Educational Resources Information Center

    McCann, Edward W.

    Developed to assist vocational agricultural mechanics students in learning to be tractor mechanics, this curriculum guide contains all the student competency sheets which comprise this competency-based curriculum. These competency sheets are categorized under sixteen instructional units. The first two units cover employment opportunities and…

  13. Operators' perception of comfort in two tractor cabs.

    PubMed

    Ferrari, E; Cavallo, E

    2013-01-01

    Workspace characteristics affect the perceived comfort level of the operator and uncomfortable working conditions have been found to have a negative impact on productivity and safety. The comfort of the operator is increasingly recognized by manufacturers as a product's added value. Comfort can positively distinguish a product and increase its competitiveness. The concept of comfort is controversial, and a clear operational definition is missing. Nevertheless, it is widely accepted that comfort is a subjective phenomenon that can be evaluated by the final users. In this study, comfort aspects of the tractor workspace interior (i.e., the cab) were investigated. Users with various levels of expertise and two medium-power utility tractors of different brands were used in a 2 x 2 mixed-factorial experimental design. Participants were involved in a dynamic assessment of the cabs, and their opinions about the different workspaces were collected through a questionnaire. Additionally, objective measurements were taken on both tractors, and subjective data were compared with objective data. Results indicate significant differences in terms of the ease of locating and operating the controls (i.e., rear-mounted three-point linkage, hydraulic system, and power take-off), the ease of starting the tractor, the ease exiting the cab, the required level of concentration in executing the tasks, the adequacy of lateral visibility from the driving station, and the level of noise at the operator's position. This article provides guidance for improving the comfort of tractor workspace interiors. Agricultural machinery manufactures would benefit from research results, differentiating themselves from competitors. PMID:23600166

  14. Test for the integrity of environmental tractor cab filtration systems.

    PubMed

    Moyer, Ernest S; Heitbrink, William A; Jensen, Paul A

    2005-10-01

    Cab filtration systems can be used to protect vehicle operators from hazardous air contaminants. In a cab filtration system, a fan draws air through filters and pressurizes the cab with this filtered air. This article describes the application of a low-cost, optical particle counter to evaluate the performance of tractor cab filtration systems. The tractors were equipped with environmental enclosures to protect the operators from pesticide exposures that occur during air blast spraying in orchards. Prior to testing, all environmental tractor cabs underwent a complete maintenance overhaul followed by a careful inspection by the manufacturer's field representative. As part of this maintenance effort, 13 tractors with cab filtration systems were tested in an enclosure. A Met One model 227B two-channel optical particle counter was used to measure the aerosol concentration outside and inside the cab. Ambient aerosol and/or aerosol generated by burning incense sticks were used to challenge the stationary cab filtration system in an enclosure. The ratio of the outside to inside concentration (Co/Ci) is the exposure reduction attained by the cab system. Alternatively, the inside concentration divided by the outside concentration times 100 (Ci/Co x 100) gives the percent penetration. All 13 tractors were tested for leak sites. Leak sites were identified and sealed. This process was repeated until each cab showed an exposure reduction ratio Co/Ci of at least 50 (aerosol penetration into the cab Ci/Co x 100 was less than 2%) at the 0.3-0.5 microm particle size interval.

  15. Operators' perception of comfort in two tractor cabs.

    PubMed

    Ferrari, E; Cavallo, E

    2013-01-01

    Workspace characteristics affect the perceived comfort level of the operator and uncomfortable working conditions have been found to have a negative impact on productivity and safety. The comfort of the operator is increasingly recognized by manufacturers as a product's added value. Comfort can positively distinguish a product and increase its competitiveness. The concept of comfort is controversial, and a clear operational definition is missing. Nevertheless, it is widely accepted that comfort is a subjective phenomenon that can be evaluated by the final users. In this study, comfort aspects of the tractor workspace interior (i.e., the cab) were investigated. Users with various levels of expertise and two medium-power utility tractors of different brands were used in a 2 x 2 mixed-factorial experimental design. Participants were involved in a dynamic assessment of the cabs, and their opinions about the different workspaces were collected through a questionnaire. Additionally, objective measurements were taken on both tractors, and subjective data were compared with objective data. Results indicate significant differences in terms of the ease of locating and operating the controls (i.e., rear-mounted three-point linkage, hydraulic system, and power take-off), the ease of starting the tractor, the ease exiting the cab, the required level of concentration in executing the tasks, the adequacy of lateral visibility from the driving station, and the level of noise at the operator's position. This article provides guidance for improving the comfort of tractor workspace interiors. Agricultural machinery manufactures would benefit from research results, differentiating themselves from competitors.

  16. Safety status of farm tractors that operate on public highways in four rural Kentucky counties.

    PubMed

    Cole, H P; Piercy, L R; Heinz, K L; Westneat, S C; Arrowsmith, H E; Raymond, K M

    2009-07-01

    Kentucky FFA students inspected 153 farm tractors for safety features that prevent operator injuries during tractor overturns, highway collisions, runovers, and power take-off (PTO) entanglements. Tractor mean age was 23.6 years (SD = 20.9). Rollover protective structures (ROPS) were present on 50.66% of tractors, but only 33.33% of these had functional seatbelts. Loose and damaged seats were found on 30.46% of tractors. In 38.99% of cases, tractor rear-wheel fenders exposed operators to moving tractor tires, and 48.67% of tractors had dangerously worn or damaged tires. Tractors with a narrow front-end stance comprised 16.11% of the total. Only 53.06% of the tractors had starters with secure hard cover by-pass starting shields that fully covered the starter terminals, and 37.37% had fully exposed terminals with no cover. PTO master shields with all parts present and undamaged were present on only 29.27% of the tractors, and in 39.02% of cases the entire shield was missing. Only 44.67% of the tractors had properly mounted and fully functional mounting and dismounting access steps and handholds. SMV emblems were missing on 53.64% of tractors and in the proper place and condition in only 25.83% of cases. Tractors with properly mounted and fully functional head and tail lights comprised 40.94% of the sample, and tractors with no functional lights comprised 24.16%. Properly mounted, clean, and functional rearview mirrors were present on only 19.87% of the tractors, and 69.54% had no rearview mirrors. The project increased farming and non-farming students' awareness of tractor safety issues, provided empirical data about the safety status of a sample of tractors that frequently travel public highways in four rural Kentucky farming counties, and promoted dialog about these issues with adult farmers and other community members with whom the students interacted. PMID:19728545

  17. ANNULUS CLOSURE TECHNOLOGY DEVELOPMENT INSPECTION/SALT DEPOSIT CLEANING MAGNETIC WALL CRAWLER

    SciTech Connect

    Minichan, R; Russell Eibling, R; James Elder, J; Kevin Kane, K; Daniel Krementz, D; Rodney Vandekamp, R; Nicholas Vrettos, N

    2008-06-01

    The Liquid Waste Technology Development organization is investigating technologies to support closure of radioactive waste tanks at the Savannah River Site (SRS). Tank closure includes removal of the wastes that have propagated to the tank annulus. Although amounts and types of residual waste materials in the annuli of SRS tanks vary, simple salt deposits are predominant on tanks with known leak sites. This task focused on developing and demonstrating a technology to inspect and spot clean salt deposits from the outer primary tank wall located in the annulus of an SRS Type I tank. The Robotics, Remote and Specialty Equipment (RRSE) and Materials Science and Technology (MS&T) Sections of the Savannah River National Laboratory (SRNL) collaborated to modify and equip a Force Institute magnetic wall crawler with the tools necessary to demonstrate the inspection and spot cleaning in a mock-up of a Type I tank annulus. A remote control camera arm and cleaning head were developed, fabricated and mounted on the crawler. The crawler was then tested and demonstrated on a salt simulant also developed in this task. The demonstration showed that the camera is capable of being deployed in all specified locations and provided the views needed for the planned inspection. It also showed that the salt simulant readily dissolves with water. The crawler features two different techniques for delivering water to dissolve the salt deposits. Both water spay nozzles were able to dissolve the simulated salt, one is more controllable and the other delivers a larger water volume. The cleaning head also includes a rotary brush to mechanically remove the simulated salt nodules in the event insoluble material is encountered. The rotary brush proved to be effective in removing the salt nodules, although some fine tuning may be required to achieve the best results. This report describes the design process for developing technology to add features to a commercial wall crawler and the results of the

  18. Metallurgical Design and Development of NASA Crawler/Transporter Tread Belt Shoe Castings

    NASA Technical Reports Server (NTRS)

    Parker, Donald S.

    2006-01-01

    The NASA Crawler/Transporters (CT-1 and CT-2) used to transport the Space Shuffles are one of the largest tracked vehicles in existence today. Two of these machines have been used to move space flight vehicles at Kennedy Space Center since the Apollo missions of the 1960's and relatively few modifications have been made to keep them operational. In September of 2003 during normal Crawler/Transporter operations cracks were observed along the roller pad surfaces of several tread belt shoes. Further examination showed 20 cracked shoes on CT-1 and 40 cracked shoes on CT-2 and a formal failure analysis investigation was undertaken while the cracked shoes were replaced. Six shoes were cross-sectioned with the fracture surfaces exposed and it was determined that the cracks were due to fatigue that initiated on the internal casting web channels at pre-existing casting defects and propagated through thickness both transgranularly and intergranularly between internal shrinkage cavities, porosity, and along austenitic and ferritic grain boundaries. The original shoes were cast during the 1960's using a modified 861330 steel with slightly higher levels of chromium, nickel and molybdenum followed by heat treatment to achieve a minimum tensile strength of 11 Oksi. Subsequent metallurgical analysis of the tread belt shoes after multiple failures showed excessive internal defects, alloy segregation, a nonuniform ferritic/ bainitic/martensitic microstructure, and low average tensile properties indicative of poor casting and poor heat-treatment. As a result, NASA funded an initiative to replace all of the tread belt shoes on both crawler/transporters along with a redesign of the alloy, manufacturing, and heat-treatment to create a homogeneous cast structure with uniform mechanical and metallurgical properties. ME Global, a wholly owned subsidiary of ME Elecmetal based in Minneapolis, MN was selected as manufacturing and design partner to develop the new shoes and this paper

  19. The BCube Crawler: Web Scale Data and Service Discovery for EarthCube.

    NASA Astrophysics Data System (ADS)

    Lopez, L. A.; Khalsa, S. J. S.; Duerr, R.; Tayachow, A.; Mingo, E.

    2014-12-01

    Web-crawling, a core component of the NSF-funded BCube project, is researching and applying the use of big data technologies to find and characterize different types of web services, catalog interfaces, and data feeds such as the ESIP OpenSearch, OGC W*S, THREDDS, and OAI-PMH that describe or provide access to scientific datasets. Given the scale of the Internet, which challenges even large search providers such as Google, the BCube plan for discovering these web accessible services is to subdivide the problem into three smaller, more tractable issues. The first, to be able to discover likely sites where relevant data and data services might be found, the second, to be able to deeply crawl the sites discovered to find any data and services which might be present. Lastly, to leverage the use of semantic technologies to characterize the services and data found, and to filter out everything but those relevant to the geosciences. To address the first two challenges BCube uses an adapted version of Apache Nutch (which originated Hadoop), a web scale crawler, and Amazon's ElasticMapReduce service for flexibility and cost effectiveness. For characterization of the services found, BCube is examining existing web service ontologies for their applicability to our needs and will re-use and/or extend these in order to query for services with specific well-defined characteristics in scientific datasets such as the use of geospatial namespaces. The original proposal for the crawler won a grant from Amazon's academic program, which allowed us to become operational; we successfully tested the Bcube Crawler at web scale obtaining a significant corpus, sizeable enough to enable work on characterization of the services and data found. There is still plenty of work to be done, doing "smart crawls" by managing the frontier, developing and enhancing our scoring algorithms and fully implementing the semantic characterization technologies. We describe the current status of the project

  20. Personal noise exposures of operators of agricultural tractors.

    PubMed

    Aybek, Ali; Kamer, H Atil; Arslan, Selçuk

    2010-03-01

    Approximately one million agricultural tractors are used in Turkey for crop production and about one-third of the population lives in rural areas. The objectives of this study were to determine sound pressure levels, A-weighted sound pressure levels, and the permissible exposure time for tractors without cabins, field-installed cabins, and original cabins at ear level of agricultural tractor operators for following machines: plows, cultivators, top soil cultivators, rotary tillers, tool combinations (harrow+roller), mechanical drills, pneumatic drills, chemical applicators, fertilizer applicators, drum mowers, balers, and forage harvesters. Variance analyses showed that type of operation, type of cabins, and operation x cabin interactions were statistically significant (P<0.01) both for sound pressure levels and equivalent (A-weighted) sound pressure levels. The use of original cabins had a greater effect in decreasing average sound pressures and resulted in more efficient noise insulation, especially at higher center frequencies compared to field-installed cabins whereas field-installed cabins proved to be more favorable compared to tractors without cabins. Sound pressure levels at 4000Hz center frequency was reduced 2-13dB and 4-18dB by using a field-installed cabin and an original cabin, respectively. The measured A-weighted equivalent sound pressure levels were compared to the threshold limit level, and was concluded that depending on the cabin types used, the operators could usually work from 4 to 6h a day without suffering from noise induced inconveniences while 2-3h is permissible for plowing and forage harvesting on tractors without cabins. Due to timeliness considerations in agricultural machine operations, a farmer would not be willing to interrupt the operation based on permissible exposure time set by the standards. Based on the findings of this study, particularly an original cabin is recommended to reduce machine-induced noise below the danger limit

  1. Helical tractor beam: analytical solution of Rayleigh particle dynamics.

    PubMed

    Carretero, Luis; Acebal, Pablo; Garcia, Celia; Blaya, Salvador

    2015-08-10

    We analyze particle dynamics in an optical force field generated by helical tractor beams obtained by the interference of a cylindrical beam with a topological charge and a co-propagating temporally de-phased plane wave. We show that, for standard experimental conditions, it is possible to obtain analytical solutions for the trajectories of particles in such force field by using of some approximations. These solutions show that, in contrast to other tractor beams described before, the intensity becomes a key parameter for the control of particle trajectories. Therefore, by tuning the intensity value the particle can describe helical trajectories upstream and downstream, a circular trajectory in a fixed plane, or a linear displacement in the propagation direction. The approximated analytical solutions show good agreement to the corresponding numerical solutions of the exact dynamical differential equations.

  2. Helical tractor beam: analytical solution of Rayleigh particle dynamics.

    PubMed

    Carretero, Luis; Acebal, Pablo; Garcia, Celia; Blaya, Salvador

    2015-08-10

    We analyze particle dynamics in an optical force field generated by helical tractor beams obtained by the interference of a cylindrical beam with a topological charge and a co-propagating temporally de-phased plane wave. We show that, for standard experimental conditions, it is possible to obtain analytical solutions for the trajectories of particles in such force field by using of some approximations. These solutions show that, in contrast to other tractor beams described before, the intensity becomes a key parameter for the control of particle trajectories. Therefore, by tuning the intensity value the particle can describe helical trajectories upstream and downstream, a circular trajectory in a fixed plane, or a linear displacement in the propagation direction. The approximated analytical solutions show good agreement to the corresponding numerical solutions of the exact dynamical differential equations. PMID:26367905

  3. A long-range polarization-controlled optical tractor beam

    NASA Astrophysics Data System (ADS)

    Shvedov, Vladlen; Davoyan, Arthur R.; Hnatovsky, Cyril; Engheta, Nader; Krolikowski, Wieslaw

    2014-11-01

    The laser beam has become an indispensable tool for the controllable manipulation and transport of microscopic objects in biology, physical chemistry and condensed matter physics. In particular, ‘tractor’ laser beams can draw matter towards a laser source and perform, for instance, all-optical remote sampling. Recent advances in lightwave technology have already led to small-scale experimental demonstrations of tractor beams. However, the realization of long-range tractor beams has not gone beyond the realm of theoretical investigations. Here, we demonstrate the stable transfer of gold-coated hollow glass spheres against the power flow of a single inhomogeneously polarized laser beam over tens of centimetres. Additionally, by varying the polarization state of the beam we can stop the spheres or reverse the direction of their motion at will.

  4. Pre-turbocharger alcohol fumigation in a diesel tractor

    SciTech Connect

    Sullivan, N.W.; Bashford, L.L.

    1981-01-01

    An M and W alcohol Conversion kit was installed on an AC 7040 turbocharged diesel tractor. The unit was dynamometer tested with 100 proof and 185 proof ethanol. This system injects alcohol into the intake air stream and permits reduction of diesel fuel-consumption by 10-15 percent. Turbocharger blade wear, as well as other problems with the system, are presented. 8 refs.

  5. High-speed optimal steering of a tractor-semitrailer

    NASA Astrophysics Data System (ADS)

    Cheng, Caizhen; Roebuck, Richard; Odhams, Andrew; Cebon, David

    2011-04-01

    A high-speed optimal trailer steering controller for a tractor-semitrailer is discussed. A linear model of a tractor-semitrailer with steered trailer axles is described, and an optimal trailer steering controller is introduced. A path-following controller is derived to minimise the path-tracking error in steady-state manoeuvres using active trailer steering. A roll stability controller is introduced by adding the lateral acceleration of trailer centre of gravity as another objective in the steering controller, so as to improve roll stability in transient manoeuvres. A strategy to switch between these two control modes is demonstrated. Simulation results show that the steering controller can ensure good path tracking of articulated vehicles in steady-state manoeuvres and improve roll stability significantly in transient manoeuvres, while maintaining the path-tracking deviation within an acceptable range. Tests with an experimental tractor-semitrailer equipped with a high-bandwidth active steering system validate the controller design and simulation results. The roll stability controller reduces the measured rearward amplification by 27%.

  6. 29 CFR 1926.1001 - Minimum performance criteria for rollover protective structures for designated scrapers, loaders...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... scrapers; rubber-tired front-end loaders and rubber-tired dozers; crawler tractors, and crawler-type... prescribed in paragraph (f) of this section for each type of machine described in this paragraph. (b) The... limited to 360° down a slope of 30° maximum. (3) For crawler tractors and crawler-type loaders:...

  7. 29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CFR 1928.51. (b) Types of tests. All protective frames for wheel-type agricultural tractors shall be... load is applied. (ii) The following definitions shall apply: W = Tractor weight (see 29 CFR 1928.51(a... conditions shall be met: (A) The protective frame and tractor shall be tested at the weight defined by 29...

  8. A Tractor or an Automobile? A 1920s Farm Family Faces a Decision.

    ERIC Educational Resources Information Center

    Kunze, Joel P.

    1991-01-01

    Outlines a lesson plan in which students role play a 1920s farm family deciding whether to buy an automobile or a tractor. Other students act as automobile and tractor sales groups. Explains how the lesson illuminates relationships between technological advance and social history. Includes handouts identifying benefits of purchasing cars or…

  9. Design and implementation of a GPS guidance system for agricultural tractors using augmented reality technology.

    PubMed

    Santana-Fernández, Javier; Gómez-Gil, Jaime; del-Pozo-San-Cirilo, Laura

    2010-01-01

    Current commercial tractor guidance systems present to the driver information to perform agricultural tasks in the best way. This information generally includes a treated zones map referenced to the tractor's position. Unlike actual guidance systems where the tractor driver must mentally associate treated zone maps and the plot layout, this paper presents a guidance system that using Augmented Reality (AR) technology, allows the tractor driver to see the real plot though eye monitor glasses with the treated zones in a different color. The paper includes a description of the system hardware and software, a real test done with image captures seen by the tractor driver, and a discussion predicting that the historical evolution of guidance systems could involve the use of AR technology in the agricultural guidance and monitoring systems.

  10. Using data crawlers and semantic Web to build financial XBRL data generators: the SONAR extension approach.

    PubMed

    Rodríguez-García, Miguel Ángel; Rodríguez-González, Alejandro; Colomo-Palacios, Ricardo; Valencia-García, Rafael; Gómez-Berbís, Juan Miguel; García-Sánchez, Francisco

    2014-01-01

    Precise, reliable and real-time financial information is critical for added-value financial services after the economic turmoil from which markets are still struggling to recover. Since the Web has become the most significant data source, intelligent crawlers based on Semantic Technologies have become trailblazers in the search of knowledge combining natural language processing and ontology engineering techniques. In this paper, we present the SONAR extension approach, which will leverage the potential of knowledge representation by extracting, managing, and turning scarce and disperse financial information into well-classified, structured, and widely used XBRL format-oriented knowledge, strongly supported by a proof-of-concept implementation and a thorough evaluation of the benefits of the approach. PMID:24587726

  11. Using data crawlers and semantic Web to build financial XBRL data generators: the SONAR extension approach.

    PubMed

    Rodríguez-García, Miguel Ángel; Rodríguez-González, Alejandro; Colomo-Palacios, Ricardo; Valencia-García, Rafael; Gómez-Berbís, Juan Miguel; García-Sánchez, Francisco

    2014-01-01

    Precise, reliable and real-time financial information is critical for added-value financial services after the economic turmoil from which markets are still struggling to recover. Since the Web has become the most significant data source, intelligent crawlers based on Semantic Technologies have become trailblazers in the search of knowledge combining natural language processing and ontology engineering techniques. In this paper, we present the SONAR extension approach, which will leverage the potential of knowledge representation by extracting, managing, and turning scarce and disperse financial information into well-classified, structured, and widely used XBRL format-oriented knowledge, strongly supported by a proof-of-concept implementation and a thorough evaluation of the benefits of the approach.

  12. Using Data Crawlers and Semantic Web to Build Financial XBRL Data Generators: The SONAR Extension Approach

    PubMed Central

    Rodríguez-García, Miguel Ángel; Rodríguez-González, Alejandro; Valencia-García, Rafael; Gómez-Berbís, Juan Miguel

    2014-01-01

    Precise, reliable and real-time financial information is critical for added-value financial services after the economic turmoil from which markets are still struggling to recover. Since the Web has become the most significant data source, intelligent crawlers based on Semantic Technologies have become trailblazers in the search of knowledge combining natural language processing and ontology engineering techniques. In this paper, we present the SONAR extension approach, which will leverage the potential of knowledge representation by extracting, managing, and turning scarce and disperse financial information into well-classified, structured, and widely used XBRL format-oriented knowledge, strongly supported by a proof-of-concept implementation and a thorough evaluation of the benefits of the approach. PMID:24587726

  13. Hours of service violations among tractor-trailer drivers.

    PubMed

    Hertz, R P

    1991-02-01

    Federal regulation limits interstate truck drivers to 10 hours of driving after an 8-hour off-duty period. The need for enforcing these limits is supported by research showing that long driving hours is a risk factor for tractor-trailer crashes. To estimate the percentage of hours of service violators among long-haul tractor-trailer drivers, truck drivers were interviewed at an inspection site in Spokane, Washington and later observed arriving at inspection sites in either Moorhead or Worthington, Minnesota (approximately 1,200 miles). The sample used for the calculation of violators consisted of truckers driving alone who reportedly did not plan to make an interim pickup or delivery stop prior to arrival in Minnesota. The percentages of drivers violating the hours of service rules by more than one hour at average trip speeds ranging from 35 mph to 65 mph are presented. Assuming that the drivers averaged 40 mph over the complete course of the trip segment, including stopped time, 90% were in violation by more than one hour. Assuming that they averaged 50 mph, 51% were in violation by more than one hour. These speed assumptions are based on findings in the current study that team drivers averaged 38 mph, fleet managers' reports of scheduling single drivers at trip speeds of 45 mph to 47 mph, and reports in the literature that loaded tractor-trailers average 41 mph over flat terrain. Although the true percentage cannot be determined without knowing actual trip speeds, the estimated range of violators at probable speeds of 40 mph and 50 mph points to a substantial problem.

  14. Defective equipment and tractor-trailer crash involvement.

    PubMed

    Jones, I S; Stein, H S

    1989-10-01

    The role of defective equipment in large truck crashes on interstate highways in Washington State was investigated using a case-control study design. For each large truck involved in a crash, three trucks were randomly selected from the traffic stream at the same time and place as the crash, but one week later both crash and comparison trucks were inspected by Commercial Vehicle Enforcement officers of the Washington State Patrol. The effects of truck equipment condition, truck operating characteristics (carrier type, carrier operation, and truck load), and driver characteristics (driver age, hours of driving) on crash involvement were analyzed by comparing their relative frequency among crash-involved and comparison sample tractor-trailers. A logistic regression model was used to estimate the adjusted odds ratio for each factor. Overall, 77% of tractor-trailers in crashes and 66% of those not involved in crashes had defective equipment warranting a citation. Forty-one percent in crashes had defective equipment warranting taking the truck out of service, and 31% not in crashes had these defects. Brake defects were the most common type and were found in 56% of tractor-trailers in crashes; steering equipment defects were found in 21%. The relative risk of crash involvement for trucks with brake defects was about one and one-half times that for trucks without brake defects. For trucks with steering defects, the relative risk of crash involvement was at least twice that for trucks with steering defects, the relative risk of crash involvement was at least twice that for trucks without defects, and the risk increased substantially for trucks with out-of-service steering defects.

  15. Space Shuttle Crawler Transporter Vibration Analysis in Support of Rollout Fatigue Load Spectra Verification Program

    NASA Technical Reports Server (NTRS)

    Margasahayam, Ravi N.; Meyer, Karl A.; Nerolich, Shaun M.; Burton, Roy C.; Gosselin, Armand M.

    2004-01-01

    The Crawler Transporter (CT), designed and built for the Apollo Program in the 1960's and surpassing its initial operational life, has become an integral part of the Space Shuttle Program (SSP). The CT transports the Space Shuttle Vehicle (SSV) stack, atop the Mobile Launch Platform (MLP), from the Vehicle Assembly Building (VAB) to the launch pad. This support structure provides hydraulic jacking, leveling and load equalization for the 12 million pound stack on its 3.5-5.0 mile rollout to the launch pad. Major elements of the SSV, consisting of the orbiter, solid rocket boosters (SRB) and external tank (ET) have required fatigue analyses as part of the mission life certification. Compared to rollout vibration, the SSV sees relatively high vibration loads during launch, ascent, descent and landing phases of the mission. Although preliminary measured SRB vibration levels during rollout were of low amplitude and frequency, the duration of the rollout phase is typically high, from 5-6 hours. As part of an expanded mission life assessment, additional certification effort was initiated to define fatigue load spectra for rollout. This study addresses the CT vibration analyses in support of the rollout fatigue study. Structural models developed for modal and vibration analyses were used to identify unique CT, CT/MLP and CT/MLP/SRB vibration characteristics for comparison to instrumented rollout tests. Whereas the main structural and vibration characteristics of the SSV are well defined, minimum analytical and vibration test data on the Crawler Transporter were available. Unique vibration characteristics of the CT are attributable to the drive mechanism, hydraulic jacking system, structural framing and the CT-to-MLP support pad restraints. Initial tests performed on the CT/MLP/SRB configuration showed reasonable correlation with predicted mode shapes and frequencies.

  16. Optimized optical "tractor beam" for core-shell nanoparticles.

    PubMed

    Wang, Neng; Lu, Wanli; Ng, Jack; Lin, Zhifang

    2014-04-15

    It is known that core-shell subwavelength nanoparticles consisting of a dielectric shell and a metallic core can simultaneously support electric and magnetic dipolar resonances, which enhance forward scattering and suppress backward scattering. This creates favorable conditions for optical tractor beam applications. Using the generalized Lorenz-Mie theory and Maxwell stress tensor formulation, we demonstrate how optical pulling forces can be induced and optimized by first-order Bessel beams with appropriate polarization. The transverse stability of the core-shell nanoparticle under ambient damping is also verified by linear stability analysis and dynamical simulation. PMID:24979003

  17. Nematoelastic crawlers

    NASA Astrophysics Data System (ADS)

    Zakharov, A. P.; Pismen, L. M.

    2016-02-01

    A propagating "beam" triggering a local phase transition in a nematic elastomer sets it into a crawling motion, which may morph due to buckling. We consider the motion of the various configurations of slender rods and thin stripes with both uniform and splayed nematic order in cross-section and detect the dependence of the gait and speed on flexural rigidity and substrate friction.

  18. Retrofitting tractors with rollover protective structures: perspective of equipment dealers.

    PubMed

    Tonelli, S M; Donham, K J; Leedom-Larson, K; Sanderson, W; Purschwitz, M

    2009-10-01

    This study was one of a cluster of studies that originated via requests for proposals from the NIOSH National Agricultural Tractor Safety Initiative. The present study design consisted of several steps: (1) formation of an advisory group, (2) development and testing of a standard paper self-responding survey instrument, (3) sample selection of farm equipment dealers, (4) administration of the survey, (5) assessment and analysis of the survey, and (6) in-person response panel of dealers (n = 80) to review results of the questionnaire for further definition and sharpening of the recommendations from the survey. A key finding is that most dealers do not currently sell or install ROPS retrofit kits. Barriers cited by dealers included (1) actual or perceived lack of farmer demand, (2) injury liability, (3) expensive freight for ordering ROPS, (4) lack of dealer awareness of the magnitude of deaths from tractor overturns and the high life-protective factor of ROPS, and (5) difficulty and incursion of non-recoverable expenses in locating and obtaining specific ROPS. Despite not currently selling or installing ROPS, dealers responded favorably about their future potential role in ROPS promotion and sales. Dealers were willing to further promote, sell, and install ROPS if there was demand from farmers. Recommendations include establishing a ROPS "clearing house" that dealers could contact to facilitate locating and obtaining ROPS orders from customers. Additional recommendations include education and social marketing targeting farm machinery dealers as well farmers, manufacturers, and policy makers. PMID:19967910

  19. Action Learning: a new method to increase tractor rollover protective structure (ROPS) adoption.

    PubMed

    Biddle, Elyce Anne; Keane, Paul R

    2012-01-01

    Action Learning is a problem-solving process that is used in various industries to address difficult problems. This project applied Action Learning to a leading problem in agricultural safety. Tractor overturns are the leading cause of fatal injury to farmworkers. This cause of injury is preventable using rollover protective structures (ROPS), protective equipment that functions as a roll bar structure to protect the operator in the event of an overturn. For agricultural tractors manufactured after 1976 and employee operated, Occupational Safety and Health Administration (OSHA) regulation requires employers to equip them with ROPS and seat belts. By the mid-1980s, US tractor manufacturers began adding ROPS on all farm tractors over 20 horsepower sold in the United States (http://www.nasdonline.org/document/113/d001656/rollover-protection-for-farm-tractor-operators.html). However, many older tractors remain in use without ROPS, putting tractor operators at continued risk for traumatic injury and fatality. For many older tractor models ROPS are available for retrofit, but for a variety of reasons, tractor owners have not chosen to retrofit those ROPS. The National Institute for Occupational Safety and Health (NIOSH) attempted various means to ameliorate this occupational safety risk, including the manufacture of a low-cost ROPS for self-assembly. Other approaches address barriers to adoption. An Action Learning approach to increasing adoption of ROPS was followed in Virginia and New York, with mixed results. Virginia took action to increase the manufacturing and adoption of ROPS, but New York saw problems that would be insurmountable. Increased focus on team composition might be needed to establish effective Action Learning teams to address this problem. PMID:22994641

  20. Action Learning: A New Method to Increase Tractor Rollover Protective Structure (ROPS) Adoption

    PubMed Central

    Biddle, Elyce Anne; Keane, Paul R.

    2016-01-01

    Action Learning is a problem-solving process that is used in various industries to address difficult problems. This project applied Action Learning to a leading problem in agricultural safety. Tractor overturns are the leading cause of fatal injury to farmworkers. This cause of injury is preventable using rollover protective structures (ROPS), protective equipment that functions as a roll bar structure to protect the operator in the event of an overturn. For agricultural tractors manufactured after 1976 and employee operated, Occupational Safety and Health Administration (OSHA) regulation requires employers to equip them with ROPS and seat belts. By the mid-1980s, US tractor manufacturers began adding ROPS on all farm tractors over 20 horsepower sold in the United States (http://www.nasdonline.org/document/113/d001656/rollover-protection-for-farm-tractor-operators.html). However, many older tractors remain in use without ROPS, putting tractor operators at continued risk for traumatic injury and fatality. For many older tractor models ROPS are available for retrofit, but for a variety of reasons, tractor owners have not chosen to retrofit those ROPS. The National Institute for Occupational Safety and Health (NIOSH) attempted various means to ameliorate this occupational safety risk, including the manufacture of a low-cost ROPS for self-assembly. Other approaches address barriers to adoption. An Action Learning approach to increasing adoption of ROPS was followed in Virginia and New York, with mixed results. Virginia took action to increase the manufacturing and adoption of ROPS, but New York saw problems that would be insurmountable. Increased focus on team composition might be needed to establish effective Action Learning teams to address this problem. PMID:22994641

  1. Pipe Crawler{reg_sign} internal piping characterization system - deactivation and decommissioning focus area. Innovative Technology Summary Report

    SciTech Connect

    1998-02-01

    Pipe Crawler{reg_sign} is a pipe surveying system for performing radiological characterization and/or free release surveys of piping systems. The technology employs a family of manually advanced, wheeled platforms, or crawlers, fitted with one or more arrays of thin Geiger Mueller (GM) detectors operated from an external power supply and data processing unit. Survey readings are taken in a step-wise fashion. A video camera and tape recording system are used for video surveys of pipe interiors prior to and during radiological surveys. Pipe Crawler{reg_sign} has potential advantages over the baseline and other technologies in areas of cost, durability, waste minimization, and intrusiveness. Advantages include potentially reduced cost, potential reuse of the pipe system, reduced waste volume, and the ability to manage pipes in place with minimal disturbance to facility operations. Advantages over competing technologies include potentially reduced costs and the ability to perform beta-gamma surveys that are capable of passing regulatory scrutiny for free release of piping systems.

  2. Quantum coherent tractor beam effect for atoms trapped near a nanowaveguide.

    PubMed

    Sadgrove, Mark; Wimberger, Sandro; Nic Chormaic, Síle

    2016-01-01

    We propose several schemes to realize a tractor beam effect for ultracold atoms in the vicinity of a few-mode nanowaveguide. Atoms trapped near the waveguide are transported in a direction opposite to the guided mode propagation direction. We analyse three specific examples for ultracold (23)Na atoms trapped near a specific nanowaveguide (i.e. an optical nanofibre): (i) a conveyor belt-type tractor beam effect, (ii) an accelerator tractor beam effect, and (iii) a quantum coherent tractor beam effect, all of which can effectively pull atoms along the nanofibre toward the light source. This technique provides a new tool for controlling the motion of particles near nanowaveguides with potential applications in the study of particle transport and binding as well as atom interferometry. PMID:27440516

  3. Effect of Road Adhesion Coefficient on Tractor-Semitrailer Cornering Braking Stability

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Li, Chen; Tang, Geteng; Wang, Cheng

    A dynamic model of tractor-semitrailer cornering braking was established in this paper, and the accuracy of the model was verified by real vehicle test. By model simulation of the cornering braking process, different road adhesion coefficient such as 0.15, 0.3, 0.45, 0.6, 0.75 was chosen to analyzed the changing curve of braking distance, articulation angle, yaw rate and lateral acceleration when initial speed of tractor-semitrailer was 30km h. The result showed that the peak values of articulation angle, yaw rate and lateral acceleration gotten by simulation were the largest. On the road of road adhesion coefficient 0.15, distance of tractor-semitrailer cornering braking was the longest. On the road of road adhesion coefficient 0.75, distance of tractor-semitrailer cornering braking was the shortest and the peak values of articulation angle, yaw rate and lateral acceleration were small relatively.

  4. Quantum coherent tractor beam effect for atoms trapped near a nanowaveguide

    PubMed Central

    Sadgrove, Mark; Wimberger, Sandro; Nic Chormaic, Síle

    2016-01-01

    We propose several schemes to realize a tractor beam effect for ultracold atoms in the vicinity of a few-mode nanowaveguide. Atoms trapped near the waveguide are transported in a direction opposite to the guided mode propagation direction. We analyse three specific examples for ultracold 23Na atoms trapped near a specific nanowaveguide (i.e. an optical nanofibre): (i) a conveyor belt-type tractor beam effect, (ii) an accelerator tractor beam effect, and (iii) a quantum coherent tractor beam effect, all of which can effectively pull atoms along the nanofibre toward the light source. This technique provides a new tool for controlling the motion of particles near nanowaveguides with potential applications in the study of particle transport and binding as well as atom interferometry. PMID:27440516

  5. Quantum coherent tractor beam effect for atoms trapped near a nanowaveguide.

    PubMed

    Sadgrove, Mark; Wimberger, Sandro; Nic Chormaic, Síle

    2016-07-21

    We propose several schemes to realize a tractor beam effect for ultracold atoms in the vicinity of a few-mode nanowaveguide. Atoms trapped near the waveguide are transported in a direction opposite to the guided mode propagation direction. We analyse three specific examples for ultracold (23)Na atoms trapped near a specific nanowaveguide (i.e. an optical nanofibre): (i) a conveyor belt-type tractor beam effect, (ii) an accelerator tractor beam effect, and (iii) a quantum coherent tractor beam effect, all of which can effectively pull atoms along the nanofibre toward the light source. This technique provides a new tool for controlling the motion of particles near nanowaveguides with potential applications in the study of particle transport and binding as well as atom interferometry.

  6. Design and Implementation of a GPS Guidance System for Agricultural Tractors Using Augmented Reality Technology

    PubMed Central

    Santana-Fernández, Javier; Gómez-Gil, Jaime; del-Pozo-San-Cirilo, Laura

    2010-01-01

    Current commercial tractor guidance systems present to the driver information to perform agricultural tasks in the best way. This information generally includes a treated zones map referenced to the tractor’s position. Unlike actual guidance systems where the tractor driver must mentally associate treated zone maps and the plot layout, this paper presents a guidance system that using Augmented Reality (AR) technology, allows the tractor driver to see the real plot though eye monitor glasses with the treated zones in a different color. The paper includes a description of the system hardware and software, a real test done with image captures seen by the tractor driver, and a discussion predicting that the historical evolution of guidance systems could involve the use of AR technology in the agricultural guidance and monitoring systems. PMID:22163479

  7. Quantum coherent tractor beam effect for atoms trapped near a nanowaveguide

    NASA Astrophysics Data System (ADS)

    Sadgrove, Mark; Wimberger, Sandro; Nic Chormaic, Síle

    2016-07-01

    We propose several schemes to realize a tractor beam effect for ultracold atoms in the vicinity of a few-mode nanowaveguide. Atoms trapped near the waveguide are transported in a direction opposite to the guided mode propagation direction. We analyse three specific examples for ultracold 23Na atoms trapped near a specific nanowaveguide (i.e. an optical nanofibre): (i) a conveyor belt-type tractor beam effect, (ii) an accelerator tractor beam effect, and (iii) a quantum coherent tractor beam effect, all of which can effectively pull atoms along the nanofibre toward the light source. This technique provides a new tool for controlling the motion of particles near nanowaveguides with potential applications in the study of particle transport and binding as well as atom interferometry.

  8. Summary of NREL's Recent Class 8 Tractor Trailer Platooning Testing (Presentation)

    SciTech Connect

    Lammert, M.; Kelly, K.; Walkowicz, K.

    2014-08-01

    This presentation summarizes NREL's recent class 8 tractor trailer platooning testing, including analysis of SAE J1321 Type II fuel consumption testing, fuel consumption improvement, fuel economy and platooning position accuracy.

  9. The smooth (tractor) operator: insights of knowledge engineering.

    PubMed

    Cullen, Ralph H; Smarr, Cory-Ann; Serrano-Baquero, Daniel; McBride, Sara E; Beer, Jenay M; Rogers, Wendy A

    2012-11-01

    The design of and training for complex systems requires in-depth understanding of task demands imposed on users. In this project, we used the knowledge engineering approach (Bowles et al., 2004) to assess the task of mowing in a citrus grove. Knowledge engineering is divided into four phases: (1) Establish goals. We defined specific goals based on the stakeholders involved. The main goal was to identify operator demands to support improvement of the system. (2) Create a working model of the system. We reviewed product literature, analyzed the system, and conducted expert interviews. (3) Extract knowledge. We interviewed tractor operators to understand their knowledge base. (4) Structure knowledge. We analyzed and organized operator knowledge to inform project goals. We categorized the information and developed diagrams to display the knowledge effectively. This project illustrates the benefits of knowledge engineering as a qualitative research method to inform technology design and training.

  10. The Tractor: Probabilistic astronomical source detection and measurement

    NASA Astrophysics Data System (ADS)

    Lang, Dustin; Hogg, David W.; Mykytyn, David

    2016-04-01

    The Tractor optimizes or samples from models of astronomical objects. The approach is generative: given astronomical sources and a description of the image properties, the code produces pixel-space estimates or predictions of what will be observed in the images. This estimate can be used to produce a likelihood for the observed data given the model: assuming the model space actually includes the truth (it doesn’t, in detail), then if we had the optimal model parameters, the predicted image would differ from the actually observed image only by noise. Given a noise model of the instrument and assuming pixelwise independent noise, the log-likelihood is the negative chi-squared difference: (image - model) / noise.

  11. Using LNG as a Fuel in Heavy-Duty Tractors

    SciTech Connect

    Liquid Carbonic, Inc. and Trucking Research Institute

    1999-08-09

    Recognizing the lack of operational data on alternative fuel heavy-truck trucks, NREL contracted with the Trucking Research Institute (TRI) in 1994 to obtain a cooperative agreement with Liquid Carbonic. The purpose of this agreement was to (1) purchase and operate liquid natural gas- (LNG-) powered heavy-duty tractor-trailers with prototype Detroit Diesel Corporation (DDC) Series 60 natural gas (S60G) engines in over-the-road commercial service applications; and (2) collect and provide operational data to DDC to facilitate the on-road prototype development of the engine and to NREL for the Alternative Fuels Data Center. The vehicles operated from August 1994 through April of 1997 and led to a commercially available, emissions-certified S60G in 1998. This report briefly documents the engine development, the operational characteristics of LNG, and the lessons learned during the project.

  12. Soil compaction and structural morphology under tractor wheelings

    NASA Astrophysics Data System (ADS)

    Shanahan, Peter; Quinton, John; Binley, Andrew; Silgram, Martyn

    2010-05-01

    Compaction of cultivated soils is a major problem for agriculture in terms of yield decline and sustainable soil resource management. Tramline wheelings exacerbate runoff and increase erosion from arable land. The UK Department for Environment, Food and Rural Affairs (Defra) LINK Project - a joint venture between agri-business, land managers and research groups - is currently evaluating a number of methods for alleviating compaction in tractor wheelings across a range of soil types in England. Using innovative applications of agri-geophysics (e.g. ground penetrating radar, electrical resistivity, acoustics and x-ray tomography), this current project aims to determine relationships between properties derived from geophysical methods (e.g. soil moisture, porosity), soil compaction and structural morphology. Such relationships are important for a clearer understanding of hydrological and biogeochemical processes in compacted soils, to address land management practices and develop cost-effective mitigation measures. Our poster will present some early results of this study.

  13. An investigation of drag reduction for tractor trailer vehicles

    NASA Technical Reports Server (NTRS)

    Muirhead, V. U.

    1978-01-01

    Force and moment data were obtained from a one-twenty-fifth scale wind tunnel model of a cab-over-engine tractor trailer combination. The tests define the aerodynamic characteristics of the baseline (unmodified) vehicle and several modified configurations. The primary modifications consist of: (1) greatly increased forebody corner radii, (2) a smooth fairing over the cab-to-trailer gap, (3) a smoothed underbody, and (4) rear streamlining (boattailing)of the trailer. Tests were conducted for yaw angles from 0 deg to 30 deg. The reduction in drag, relative to the baseline, obtained by combining the modifications are compared for the zero yaw condition with full scale coast down drag results for similar configurations. The drag reductions obtained from the model and full scale tests are in good agreement.

  14. Prevalence of drug use in commercial tractor-trailer drivers.

    PubMed

    Couper, Fiona J; Pemberton, Melissa; Jarvis, Anjanette; Hughes, Marty; Logan, Barry K

    2002-05-01

    An enforcement emphasis project, "Operation Trucker Check," was established in order to determine the extent to which commercial tractor-trailer drivers were operating their vehicles while impaired by drugs. A total of 1079 drivers and their vehicles were assessed for driver and equipment violations, and drivers additionally underwent preliminary field sobriety tests conducted by drug recognition expert (DRE) officers. Anonymous urine specimens for drug analysis were requested, and 822 urine specimens were obtained in total. Compliance with the drug-testing portion was voluntary, and there was a 19% refusal rate. Overall, 21% of the urine specimens tested positive for either illicit, prescription, and/or over-the-counter drugs, and 7% tested positive for more than one drug. Excluding caffeine and nicotine, the largest number of positive findings (9.5%) were for CNS stimulants, such as methamphetamine, amphetamine, phentermine, ephedrine/pseudoephedrine, and cocaine. The second most frequently encountered drug class were the cannabinoids, with 4.3% of drivers testing positive for marijuana metabolites. Only 11 drivers (1.3%) were positive for alcohol. Sixteen truck drivers (1.6%) were charged with driving under the influence of drugs after a full DRE evaluation was conducted. The results indicate that in spite of comprehensive drug testing in the trucking industry, some tractor-trailer drivers are continuing to take illicit and other drugs with the potential of having a negative effect on their driving ability. On the other hand, only a few drivers were, in fact, deemed to be under the influence of drugs at the time of driving when evaluated by DRE officers.

  15. Prevalence of drug use in commercial tractor-trailer drivers.

    PubMed

    Couper, Fiona J; Pemberton, Melissa; Jarvis, Anjanette; Hughes, Marty; Logan, Barry K

    2002-05-01

    An enforcement emphasis project, "Operation Trucker Check," was established in order to determine the extent to which commercial tractor-trailer drivers were operating their vehicles while impaired by drugs. A total of 1079 drivers and their vehicles were assessed for driver and equipment violations, and drivers additionally underwent preliminary field sobriety tests conducted by drug recognition expert (DRE) officers. Anonymous urine specimens for drug analysis were requested, and 822 urine specimens were obtained in total. Compliance with the drug-testing portion was voluntary, and there was a 19% refusal rate. Overall, 21% of the urine specimens tested positive for either illicit, prescription, and/or over-the-counter drugs, and 7% tested positive for more than one drug. Excluding caffeine and nicotine, the largest number of positive findings (9.5%) were for CNS stimulants, such as methamphetamine, amphetamine, phentermine, ephedrine/pseudoephedrine, and cocaine. The second most frequently encountered drug class were the cannabinoids, with 4.3% of drivers testing positive for marijuana metabolites. Only 11 drivers (1.3%) were positive for alcohol. Sixteen truck drivers (1.6%) were charged with driving under the influence of drugs after a full DRE evaluation was conducted. The results indicate that in spite of comprehensive drug testing in the trucking industry, some tractor-trailer drivers are continuing to take illicit and other drugs with the potential of having a negative effect on their driving ability. On the other hand, only a few drivers were, in fact, deemed to be under the influence of drugs at the time of driving when evaluated by DRE officers. PMID:12051337

  16. Exposure to audible and infrasonic noise by modern agricultural tractors operators.

    PubMed

    Bilski, Bartosz

    2013-03-01

    The wheeled agricultural tractor is one of the most prominent sources of noise in agriculture. This paper presents the assessment of the operator's exposure to audible and infrasonic noise in 32 selected modern wheeled agricultural tractors designed and produced by world-renowned companies in normal working conditions. The tractors have been in use for no longer than 4 years, with rated power of 51 kW to up to 228 kW (as per 97/68 EC). Audible and infrasonic noise level measurements and occupational exposure analysis to noise were performed according to ISO 9612:2009 (strategy 1 - task-based measurements). The measurements were made in different typical work conditions inside and outside of tractors cabs. The results indicated that exposure levels to noise perceived by the operators (L(ex,Te) between 62,3 and 84,7 dB-A) and can make a small risk of potential adversely effects on hearing during tasks performed inside the closed cab. It should be remarked that uncertainty interval is wider and in in some conditions can occur transgression of audible noise occupational exposure limits. The measured audible noise levels can potentially develop the non-auditory effects. Analysed tractors emit considerable infrasonic noise levels that tend to exceed the occupational exposure limits (both inside and outside the driver's cab). The levels of infrasound: 83,8-111,4 dB-G. All tractors introduced for sale should be subjected to tests in terms of infrasonic noise levels. The applicable standards for low frequency noise and its measurement methods for vehicles, including agricultural tractors, should be scientifically revised. In the last years there has been a noticeable technical progress in reduction of audible noise exposure at the tractors operators workplaces with simultaneously lack of important works for limitation of exposure to infrasound. Author discuss possible health and ergonomic consequencies of such exposure. PMID:22877701

  17. Investigation of Tractor Base Bleeding for Heavy Vehicle Aerodynamic Drag Reduction

    SciTech Connect

    Ortega, J; Salari, K; Storms, B

    2007-10-25

    One of the main contributors to the aerodynamic drag of a heavy vehicle is tractor-trailer gap drag, which arises when the vehicle operates within a crosswind. Under this operating condition, freestream flow is entrained into the tractor-trailer gap, imparting a momentum exchange to the vehicle and subsequently increasing the aerodynamic drag. While a number of add-on devices, including side extenders, splitter plates, vortex stabilizers, and gap sealers, have been previously tested to alleviate this source of drag, side extenders remain the primary add-on device of choice for reducing tractor-trailer gap drag. However, side extenders are not without maintenance and operational issues. When a heavy vehicle pivots sharply with respect to the trailer, as can occur during loading or unloading operations, the side extenders can become crushed against the trailer. Consequently, fleet operators are forced to incur additional costs to cover the repair or replacement of the damaged side extenders. This issue can be overcome by either shortening the side extenders or by devising an alternative drag reduction concept that can perform just as effectively as side extenders. To explore such a concept, we investigate tractor base bleeding as a means of reducing gap drag. Wind tunnel measurements are made on a 1:20 scale heavy vehicle model at a vehicle width-based Reynolds number of 420,000. The tractor bleeding flow, which is delivered through a porous material embedded within the tractor base, is introduced into the tractor-trailer gap at bleeding coefficients ranging from 0.0-0.018. To determine the performance of tractor base bleeding under more realistic operating conditions, computational fluid dynamics simulations are performed on a full-scale heavy vehicle within a crosswind for bleeding coefficients ranging from 0.0-0.13.

  18. Exposure to audible and infrasonic noise by modern agricultural tractors operators.

    PubMed

    Bilski, Bartosz

    2013-03-01

    The wheeled agricultural tractor is one of the most prominent sources of noise in agriculture. This paper presents the assessment of the operator's exposure to audible and infrasonic noise in 32 selected modern wheeled agricultural tractors designed and produced by world-renowned companies in normal working conditions. The tractors have been in use for no longer than 4 years, with rated power of 51 kW to up to 228 kW (as per 97/68 EC). Audible and infrasonic noise level measurements and occupational exposure analysis to noise were performed according to ISO 9612:2009 (strategy 1 - task-based measurements). The measurements were made in different typical work conditions inside and outside of tractors cabs. The results indicated that exposure levels to noise perceived by the operators (L(ex,Te) between 62,3 and 84,7 dB-A) and can make a small risk of potential adversely effects on hearing during tasks performed inside the closed cab. It should be remarked that uncertainty interval is wider and in in some conditions can occur transgression of audible noise occupational exposure limits. The measured audible noise levels can potentially develop the non-auditory effects. Analysed tractors emit considerable infrasonic noise levels that tend to exceed the occupational exposure limits (both inside and outside the driver's cab). The levels of infrasound: 83,8-111,4 dB-G. All tractors introduced for sale should be subjected to tests in terms of infrasonic noise levels. The applicable standards for low frequency noise and its measurement methods for vehicles, including agricultural tractors, should be scientifically revised. In the last years there has been a noticeable technical progress in reduction of audible noise exposure at the tractors operators workplaces with simultaneously lack of important works for limitation of exposure to infrasound. Author discuss possible health and ergonomic consequencies of such exposure.

  19. Space Shuttle Crawler Transporter Truck Shoe Qualification Tests and Analyses for Return-to-Flight

    NASA Technical Reports Server (NTRS)

    Margasahayam, Ravi N.; Meyer, Karl A.; Burton, Roy C.; Gosselin, Armand M.

    2005-01-01

    A vital element to Launch Complex 39 (LC39) and NASA's Kennedy Space Center (KSC) mobile launch transfer operation is a 3 million kilogram behemoth known as the Crawler Transporter (CT). Built in the 1960's, two CT's have accumulated over 1700+ miles each and have been used for the Apollo and the Space Shuttle programs. Recent observation of fatigue cracks on the CT shoes led to a comprehensive engineering, structural and metallurgical evaluation to assess the root cause that necessitated procurement of over 1000 new shoes. This paper documents the completed dynamic and compression tests on the old and new shoes respectively, so as to certify them for Space Shuttle's return-to-flight (RTF). Measured strain data from the rollout tests was used to develop stress/loading spectra and static equivalent load for qualification testing of the new shoes. Additionally, finite element analysis (FEA) was used to conduct sensitivity analyses of various contact parameters and structural characteristics for acceptance of new shoes.

  20. Field Tests of a Tractor Rollover Detection and Emergency Notification System.

    PubMed

    Liu, B; Koc, A B

    2015-04-01

    The objective of this research was to assess the feasibility of a rollover detection and emergency notification system for farm tractors using field tests. The emergency notification system was developed based on a tractor stability model and implemented on a mobile electronic device with the iOS operating system. A complementary filter was implemented to combine the data from the accelerometer and gyroscope sensors to improve their accuracies in calculating the roll and pitch angles and the roll and pitch rates. The system estimates a stability index value during tractor operation, displays feedback messages when the stability index is lower than a preset threshold value, and transmits emergency notification messages when an overturn happens. Ten tractor rollover tests were conducted on a field track. The developed system successfully monitored the stability of the tractor during all of the tests. The iOS application was able to detect rollover accidents and transmit emergency notifications in the form of a phone call and email when an accident was detected. The system can be a useful tool for training and education in safe tractor operation. The system also has potential for stability monitoring and emergency notification of other on-road and off-road motorized vehicles. PMID:26204787

  1. The Social Marketing of Safety Behaviors: A Quasi–Randomized Controlled Trial of Tractor Retrofitting Incentives

    PubMed Central

    Jenkins, Paul L.; Emmelin, Maria; Stenlund, Hans; Weinehall, Lars; Earle-Richardson, Giulia B.; May, John J.

    2011-01-01

    Objectives. We assessed the effect of social marketing incentives on dispositions toward retrofitting and retrofitting behavior among farmers whose tractors lacked rollover protective structures. Methods. From 2006 to 2007, we conducted a quasi–randomized controlled trial with 391 farm owners in New York and Pennsylvania surveyed before and after exposure to 1 of 3 tractor retrofitting incentive combinations. These combinations were offered in 3 trial regions; region 1 received rebates; region 2 received rebates, messages, and promotion and was considered the social marketing region; and region 3 received messages and promotion. A fourth region served as a control. Results. The social marketing region generated the greatest increases in readiness to retrofit, intentions to retrofit, and message recall. In addition, postintervention stage of change, intentions, attitudes, subjective norms, and perceived behavioral control levels were higher among farmers who had retrofitted tractors. Conclusions. Our results showed that a social marketing approach (financial incentives, tailored messages, and promotion) had the greatest influence on message recall, readiness to retrofit tractors, and intentions to retrofit tractors and that behavioral measures were fairly good predictors of tractor retrofitting behaviors. PMID:21330581

  2. Anthropometric criteria for the design of tractor cabs and protection frames.

    PubMed

    Hsiao, H; Whitestone, J; Bradtmiller, B; Whisler, R; Zwiener, J; Lafferty, C; Kau, T-Y; Gross, M

    2005-03-15

    Improved human-tractor interface designs, such as well-accommodated operator enclosures (i.e. cabs and protection frames) can enhance operator productivity, comfort and safety. This study investigated farm-worker anthropometry and determined the critical anthropometric measures and 3-D feature envelopes of body landmarks for the design of tractor operator enclosures. One hundred agriculture workers participated in the study. Their body size and shape information was registered, using a 3-D full-body laser scanner. Knee height (sitting) and another eight parameters were found to affect the cab-enclosure accommodation rating and multiple anthropometric dimensions interactively affected the steering wheel and gear-handle impediment. A principal component analysis has identified 15 representative human body models for digitally assessing tractor-cab accommodation. A set of centroid coordinates of 34 body landmarks and the 95% confidence semi-axis-length for each landmark location were developed to guide tractor designers in their placement of tractor control components in order to best accommodate the user population. Finally, the vertical clearance (90 cm) for agriculture tractor enclosure in the current SAE International J2194 standard appeared to be too short as compared to the 99th percentile sitting height of male farm workers in this study (100.6 cm) and in the 1994 National Health and Nutrition Examination Survey III database (99.9 cm) and of the male civilian population in the 2002 Civilian American and European Surface Anthropometric Resource database (100.4 cm). PMID:15804844

  3. Implementing a National Tractor Safety Program: Using "Whole System in a Room" to Mobilize Partners and Implement Solutions.

    PubMed

    Tinc, Pamela J; Ayers, Paul; May, John J; Purschwitz, Mark A; Park, Samantha; Bayes, Barbara; Sorensen, Julie

    2016-01-01

    Fatalities due to tractor overturns have long plagued the U.S. farm community. Constituting 20% of agricultural fatalities, tractor overturns contribute significantly to high rates of fatal injuries. In the past, many efforts have been directed toward reducing tractor overturns, with one successful US-based program offering rebates to farmers who retrofit their tractors with rollover protective structures (ROPS). In an effort to expand the program, the National Tractor Safety Coalition was formed. This coalition hosted a "Whole System in the Room" workshop to bring 50 stakeholders together. During this workshop, participants worked together to identify a common vision for the future of tractor safety and ROPS programs and commit to action. At the close of the workshop, coalition members set out to begin work on 100 short- and long-term commitments to begin implementing a National ROPS Rebate Program. PMID:26788905

  4. Frequency and severity of injuries to operators during overturns of farm tractors.

    PubMed

    Cole, H P; Myers, M L; Westneat, S C

    2006-05-01

    Previous estimates of operator death from farm tractor overturn events range from 0.03 to 0.68. This study provided population-based estimates of the denominator of total farm tractor overturns and the frequency of six classes of overturn injury outcomes for tractors with and without rollover protective structures (ROPS). A 40-item telephone survey collected information from a random sample of 6,063 (8.0%) Kentucky farms about each farm's most recent overturn. A total of 551 (9.1%) farms reported overturns, and 5,512 (90.1%) reported no overturns. Injury outcomes for 443 overturns of non-ROPS tractors and 89 ROPS tractors were distributed as follows: no or minor injury (non-ROPS: 70.43%; ROPS: 82.02%), outpatient treatment (non-ROPS: 21.90%; ROPS: 9.00%), hospital admission (non-ROPS: 15.35%; ROPS: 3.37%), temporary disability (non-ROPS: 13.54%; ROPS: 14.61%), permanent disability (non-ROPS: 3.16%; ROPS: 0.00%), and death (non-ROPS: 5.42%; ROPS: 1.12%). (Percents total to more than 100 because some operators treated as outpatients were subsequently hospitalized, disabled, or died.) The observed 0.054 probability of death from overturn of non-ROPS tractors in this sample was corrected for the proportion of farms that went out of business prior to the survey and thus were excluded from the sampling frame. The adjusted 0.08 probability of death from overturn of a non-ROPS tractor is five times smaller than the NIOSH estimate of 0.40. The discrepancy lies in the much larger denominator of all non-fatal and fatal overturns than assumed previously. PMID:16724789

  5. RANS simulations of a simplified tractor/trailer geometry.

    SciTech Connect

    Roy, Christopher John; McWherter-Payne, Mary Anna; Salari, Kambiz; Payne, Jeffrey L.

    2003-07-01

    Steady-state Reynolds-averaged Navier-Stokes (RANS) simulations are presented for the three-dimensional flow over a simplified tractor/trailer geometry at zero degrees yaw angle. The simulations are conducted using a multi-block, structured computational fluid dynamics (CFD) code. The turbulence closure model employed is the two-equation Menter k-{omega} model. The discretization error is estimated by employing two grid levels: a fine mesh of 20 million cells and a coarser mesh of 2.5 million cells. Simulation results are compared to experimental data obtained at the NASA-Ames 7 x 10 ft wind tunnel. Quantities compared include vehicle drag, surface pressures, and time-averaged velocities in the trailer near wake. The results indicate that the RANS approach is able to accurately predict the surface pressure on the vehicle, with the exception of the base region. The pressure predictions in the base region are poor due to the inability of the RANS model to accurately capture the near-wake vortical structure. However, the gross pressure levels in the base region are in reasonable agreement with experiment, and thus the overall vehicle drag is well predicted.

  6. A Kalman filter implementation for precision improvement in low-cost GPS positioning of tractors.

    PubMed

    Gomez-Gil, Jaime; Ruiz-Gonzalez, Ruben; Alonso-Garcia, Sergio; Gomez-Gil, Francisco Javier

    2013-01-01

    Low-cost GPS receivers provide geodetic positioning information using the NMEA protocol, usually with eight digits for latitude and nine digits for longitude. When these geodetic coordinates are converted into Cartesian coordinates, the positions fit in a quantization grid of some decimeters in size, the dimensions of which vary depending on the point of the terrestrial surface. The aim of this study is to reduce the quantization errors of some low-cost GPS receivers by using a Kalman filter. Kinematic tractor model equations were employed to particularize the filter, which was tuned by applying Monte Carlo techniques to eighteen straight trajectories, to select the covariance matrices that produced the lowest Root Mean Square Error in these trajectories. Filter performance was tested by using straight tractor paths, which were either simulated or real trajectories acquired by a GPS receiver. The results show that the filter can reduce the quantization error in distance by around 43%. Moreover, it reduces the standard deviation of the heading by 75%. Data suggest that the proposed filter can satisfactorily preprocess the low-cost GPS receiver data when used in an assistance guidance GPS system for tractors. It could also be useful to smooth tractor GPS trajectories that are sharpened when the tractor moves over rough terrain. PMID:24217355

  7. A Kalman Filter Implementation for Precision Improvement in Low-Cost GPS Positioning of Tractors

    PubMed Central

    Gomez-Gil, Jaime; Ruiz-Gonzalez, Ruben; Alonso-Garcia, Sergio; Gomez-Gil, Francisco Javier

    2013-01-01

    Low-cost GPS receivers provide geodetic positioning information using the NMEA protocol, usually with eight digits for latitude and nine digits for longitude. When these geodetic coordinates are converted into Cartesian coordinates, the positions fit in a quantization grid of some decimeters in size, the dimensions of which vary depending on the point of the terrestrial surface. The aim of this study is to reduce the quantization errors of some low-cost GPS receivers by using a Kalman filter. Kinematic tractor model equations were employed to particularize the filter, which was tuned by applying Monte Carlo techniques to eighteen straight trajectories, to select the covariance matrices that produced the lowest Root Mean Square Error in these trajectories. Filter performance was tested by using straight tractor paths, which were either simulated or real trajectories acquired by a GPS receiver. The results show that the filter can reduce the quantization error in distance by around 43%. Moreover, it reduces the standard deviation of the heading by 75%. Data suggest that the proposed filter can satisfactorily preprocess the low-cost GPS receiver data when used in an assistance guidance GPS system for tractors. It could also be useful to smooth tractor GPS trajectories that are sharpened when the tractor moves over rough terrain. PMID:24217355

  8. Complementing computationally predicted regulatory sites in Tractor_DB using a pattern matching approach.

    PubMed

    Guía, Marylens Hernández; Pérez, Abel González; Angarica, Vladimir Espinosa; Vasconcelos, Ana T; Collado-Vides, Julio

    2005-01-01

    Prokaryotic genomes annotation has focused on genes location and function. The lack of regulatory information has limited the knowledge on cellular transcriptional regulatory networks. However, as more phylogenetically close genomes are sequenced and annotated, the implementation of phylogenetic footprinting strategies for the recognition of regulators and their regulons becomes more important. In this paper we describe a comparative genomics approach to the prediction of new gamma-proteobacterial regulon members. We take advantage of the phylogenetic proximity of Escherichia coli and other 16 organisms of this subdivision and the intensive search of the space sequence provided by a pattern-matching strategy. Using this approach we complement predictions of regulatory sites made using statistical models currently stored in Tractor_DB, and increase the number of transcriptional regulators with predicted binding sites up to 86. All these computational predictions may be reached at Tractor_DB (www.bioinfo.cu/Tractor_DB, www.tractor.lncc.br, www.ccg.unam.mx/Computational_Genomics/tractorDB/). We also take a first step in this paper towards the assessment of the conservation of the architecture of the regulatory network in the gamma-proteobacteria through evaluating the conservation of the overall connectivity of the network. PMID:15972018

  9. Impact of tracked and rubber-tired tractors on a forest soil

    SciTech Connect

    Burger, J.A.; Perumpral, J.V.; Kreh, R.E.; Jorbet, J.L.; Minaei, S.

    1985-03-01

    Despite a three-fold difference in mean ground pressure, changes in soil density and porosity caused by an unloaded, rubber-tired log skidder did not exceed those caused by a crawler. The changes in soil density and porosity caused by these machines increased with soil moisture content. Soil density and porosity change proportionally with the square root of the number of passes over the same area. 24 references.

  10. 29 CFR 1928.51 - Roll-over protective structures (ROPS) for tractors used in agricultural operations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... tractors shall meet the test and performance requirements of 29 CFR 1928.52, 1928.53, or 1926.1002 as appropriate. A ROPS used on track-type tractors shall meet the test and performance requirements of 29 CFR... seatbelt sufficiently to confine the employee to the protected area provided by the ROPS. (ii)...

  11. 29 CFR 1928.51 - Roll-over protective structures (ROPS) for tractors used in agricultural operations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... tractors shall meet the test and performance requirements of 29 CFR 1928.52, 1928.53, or 1926.1002 as appropriate. A ROPS used on track-type tractors shall meet the test and performance requirements of 29 CFR..., vineyards or hop yards where the vertical clearance requirements would substantially interfere with...

  12. Using Web Crawler Technology for Text Analysis of Geo-Events: A Case Study of the Huangyan Island Incident

    NASA Astrophysics Data System (ADS)

    Hu, H.; Ge, Y. J.

    2013-11-01

    With the social networking and network socialisation have brought more text information and social relationships into our daily lives, the question of whether big data can be fully used to study the phenomenon and discipline of natural sciences has prompted many specialists and scholars to innovate their research. Though politics were integrally involved in the hyperlinked word issues since 1990s, automatic assembly of different geospatial web and distributed geospatial information systems utilizing service chaining have explored and built recently, the information collection and data visualisation of geo-events have always faced the bottleneck of traditional manual analysis because of the sensibility, complexity, relativity, timeliness and unexpected characteristics of political events. Based on the framework of Heritrix and the analysis of web-based text, word frequency, sentiment tendency and dissemination path of the Huangyan Island incident is studied here by combining web crawler technology and the text analysis method. The results indicate that tag cloud, frequency map, attitudes pie, individual mention ratios and dissemination flow graph based on the data collection and processing not only highlight the subject and theme vocabularies of related topics but also certain issues and problems behind it. Being able to express the time-space relationship of text information and to disseminate the information regarding geo-events, the text analysis of network information based on focused web crawler technology can be a tool for understanding the formation and diffusion of web-based public opinions in political events.

  13. Tractor-trailer driver fatality: the role of nonconsecutive rest in a sleeper berth.

    PubMed

    Hertz, R P

    1988-12-01

    Federal regulation allows truck drivers to use sleeper berths to accumulate eight hours of off-duty rest in two separate periods. Because sleep disruption may cause fatigue and deterioration of performance, a study was conducted to evaluate the association between sleeper-berth use in two periods and tractor-trailer driver fatality. Using Bureau of Motor Carrier Safety Reports, crashes that resulted in tractor-trailer driver fatality were compared with property damage crashes. After adjusting for confounding variables by logistic regression, tractor-trailer driver fatality was found to be significantly associated with sleeper-berth use in two shifts (odds ratio = 3.05). Statistically significant but weaker associations were found between driver fatality and rural district, night driving, gross vehicle weight of 72,000 pounds or more, single-vehicle collision, intercity trip, and employment on an occasional basis.

  14. Towing Asteroids with Gravity Tractors Enhanced by Tethers and Solar Sails

    NASA Technical Reports Server (NTRS)

    Shen, Haijun; Roithmayr, Carlos M.

    2015-01-01

    Material collected from an asteroid's surface can be used to increase gravitational attraction between the asteroid and a Gravity Tractor (GT); the spacecraft therefore operates more effectively and is referred to as an Enhanced Gravity Tractor (EGT). The use of tethers and solar sails to further improve effectiveness and simplify operations is investigated. By employing a tether, the asteroidal material can be placed close to the asteroid while the spacecraft is stationed farther away, resulting in a better safety margin and improved thruster efficiency. A solar sail on a spacecraft can naturally provide radial offset and inter-spacecraft separation required for multiple EGTs.

  15. A three body dynamic simulation of a seated tractor rocket escape system for the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Ondler, R. M.

    1989-01-01

    In the tractor-rocket seated-extraction candidate system for Space Shuttle Orbiter crew escape, the crewmember is pulled from his seat and away from the Orbiter via an elastic pendant, using a system of rails to guide the extraction trajectory through an opening on the window frame for flight deck crew and through the side hatch for the middeck crew. A three-body simulation has been developed to model the flight-mechanics aspects of the concept, where the three bodies are the astronaut (six DOF), the tractor rocket (six DOF), and the Shuttle Orbiter (three DOF); attention is given to crewmembers' clearance of the Orbiter structure and engine plumes.

  16. Evaluation of Corrosion Failure in Tractor-Trailer Brake System

    SciTech Connect

    Wilson, DF

    2002-10-22

    As reported to ORNL, concomitant with the introduction of different deicing and anti-icing compounds, there was an increase in the brake failure rate of tractor-trailer trucks. A forensic evaluation of a failed brake system was performed. Optical and scanning electron microscopic evaluation showed corrosion to be mostly confined to the brake table/lining interface. The corrosion is non-uniform as is to be expected for plain carbon steel in chloride environments. This initial analysis found no evidence for the chlorides of calcium and magnesium, which are the newly introduced deicing and antiicing compounds and are less soluble in water than the identified chlorides of sodium and potassium, in the scale. The result could be as a result of non-exposure of the examined brake table to calcium and magnesium chloride. The mechanisms for the increased failure rate are postulated as being an increased rate of corrosion due to positive shifts in the corrosion potential, and an increased amount of corrosion due to an increased ''time of wetness'' that results from the presence of hygroscopic salts. Laboratory scale evaluation of the corrosion of plain carbon steel in simulated deicing and anti-icing solutions need to be performed to determine corrosion rates and morphological development of corrosion product, to compare laboratory data to in-service data, and to rank economically feasible replacement materials for low carbon steel. In addition, the mechanical behavior of the lining attached to the brake shoe table needs to be assessed. It is opined that an appropriate adjustment of materials could easily allow for a doubling of a brake table/lining lifetime. Suggestions for additional work, to clarify the mechanisms of rust jacking and to develop possible solutions, are described.

  17. 30 CFR 56.14130 - Roll-over protective structures (ROPS) and seat belts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) and seat belts shall be installed on— (1) Crawler tractors and crawler loaders; (2) Graders; (3) Wheel loaders and wheel tractors; (4) The tractor portion of semi-mounted scrapers, dumpers, water wagons, bottom-dump wagons, rear-dump wagons, and towed fifth wheel attachments; (5) Skid-steer loaders; and...

  18. A History of the Caterpillar Tractor Company's Use of Motion Pictures.

    ERIC Educational Resources Information Center

    Veeder, Gerry A.

    Film historians have tended to overlook the industrial film even though it has been widely used as a sales tool since early in this century. The Caterpillar Tractor Company was one of the first to adopt this medium as a means of demonstrating what its machines could do in a variety of situations. While other types of films have been made by…

  19. The Development of Procedural Knowledge in Adults Engaged in a Tractor-Trailer Task.

    ERIC Educational Resources Information Center

    Moses, Nelson

    1994-01-01

    Studied development of procedural knowledge in 14 adults, aged 18 to 35 years, engaged in a novel task using a toy tractor-trailer rig. Results revealed three phases of development in subjects' knowledge of steering procedures and the rig's movement patterns, and their use of feedback information. Subjects also manifested different levels of…

  20. GASOLINE TRACTOR ENGINE SYSTEMS. AGRICULTURAL MACHINERY--SERVICE OCCUPATIONS, MODULE NUMBER 14.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center for Vocational and Technical Education.

    ONE OF A SERIES DESIGNED TO HELP TEACHERS PREPARE POSTSECONDARY STUDENTS FOR AGRICULTURAL MACHINERY SERVICE OCCUPATIONS AS PARTS MEN, MECHANICS, MECHANIC'S HELPERS, AND SERVICE SUPERVISORS, THIS GUIDE AIMS TO DEVELOP STUDENT UNDERSTANDING OF THE OPERATION, COMPONENTS, AND FUNCTIONS OF VARIOUS GASOLINE TRACTOR ENGINE SYSTEMS. IT WAS DEVELOPED BY A…

  1. 49 CFR 399.207 - Truck and truck-tractor access requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Vehicles § 399.207 Truck and truck-tractor access requirements. (a) General rule. Any person entering or... equipped on each side of the vehicle where a seat is located, with a sufficient number of steps and... vehicle at unladen weight. (2) Distance between steps. The distance between steps, up to and including...

  2. 49 CFR 399.207 - Truck and truck-tractor access requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Vehicles § 399.207 Truck and truck-tractor access requirements. (a) General rule. Any person entering or... equipped on each side of the vehicle where a seat is located, with a sufficient number of steps and... vehicle at unladen weight. (2) Distance between steps. The distance between steps, up to and including...

  3. Analysis of bifurcation and stability for a tractor semi-trailer in planar motion

    NASA Astrophysics Data System (ADS)

    Ding, Nenggen; Shi, Xiaobo; Zhang, Yipeng; Chen, Wen

    2014-12-01

    This paper is intended for bifurcation analysis of a nonlinear tractor semi-trailer vehicle model in planar motion and for investigating its stability under constant running conditions. Bifurcation analysis shows that bifurcation diagrams of a tractor semi-trailer are quite different from those of a single-unit vehicle. Some instability phenomena of the vehicle system such as jackknifing, sideslip, and spinning are explained by correlating them with the behaviour in the neighbourhood of unstable fixed points based on analysis of eigenvectors, phase trajectories, and status of lateral tyre force saturation. It is also found that yaw planar instability of a tractor semi-trailer is caused by lateral tyre force saturation of the tractor's rear axles and/or the trailer's axles. Moreover, the stability region in the state space is demarcated, and a stability index for evaluating size of the stability region in a feasible domain is proposed. Yaw stability under constant driving conditions is analysed by using the proposed stability index.

  4. New method of space debris cleaning based on light negative force: tractor laser

    NASA Astrophysics Data System (ADS)

    Sun, Qiongge; Gao, Long; Li, Chen

    2016-01-01

    This paper presents a new way of space debris removal and protection, that is, using tractor laser, which based on light negative force, to achieve space debris cleaning and shielded. Tractor laser is traceable from the theory of optical tweezers, accompanied with non-diffraction beam. These kind of optical beams have the force named negative force pointing to optical source, this will bring the object along the trajectory of laser beam moving to the optical source. The negative force leads to the new method to convey and sampling the space micro-objects. In this paper, the application of tractor laser in the space debris collection and protection of 1cm is studied. The application of the several tractor beams in the space debris and sample collection is discussed. The proposed method can reduce the requirements of the laser to the satellite platform, and realize the collection of space debris, make the establishment of the space garbage station possible, and help to study the spatial non contact sample transmission and reduce the risk of space missions.

  5. Off-axial acoustic radiation force of repulsor and tractor bessel beams on a sphere.

    PubMed

    Silva, Glauber T; Lopes, J Henrique; Mitri, Farid G

    2013-06-01

    Acoustic Bessel beams are known to produce an axial radiation force on a sphere centered on the beam axis (on-axial configuration) that exhibits both repulsor and tractor behaviors. The repulsor and the tractor forces are oriented along the beam's direction of propagation and opposite to it, respectively. The behavior of the acoustic radiation force generated by Bessel beams when the sphere lies outside the beam's axis (off-axial configuration) is unknown. Using the 3-D radiation force formulas given in terms of the partial wave expansion coefficients for the incident and scattered waves, both axial and transverse components of the force exerted on a silicone- oil sphere are obtained for a zero- and a first-order Bessel vortex beam. As the sphere departs from the beam's axis, the tractor force becomes weaker. Moreover, the behavior of the transverse radiation force field may vary with the sphere's size factor ka (where k is the wavenumber and a is the sphere radius). Both stable and unstable equilibrium regions around the beam's axis are found, depending on ka values. These results are particularly important for the design of acoustical tractor beam devices operating with Bessel beams. PMID:25004483

  6. Tractor Mechanics: Maintaining and Servicing the Fuel System. Learning Activity Packages 20-33.

    ERIC Educational Resources Information Center

    Clemson Univ., SC. Vocational Education Media Center.

    Learning activity packages are presented for instruction in tractor mechanics. The packages deal with the duties involved in maintaining the fuel system. The following fourteen learning activity packages are included: servicing fuel and air filters, servicing fuel tanks and lines, adjusting a carburetor, servicing a carburetor, servicing the…

  7. Vocational Agriculture Training Program: Safe Tractor and Farm Machinery Operation. Special Paper No. 8. Second Revision.

    ERIC Educational Resources Information Center

    Bobbitt, Frank; Doss, Howard

    The publication was prepared for the United States Office of Education for use by teachers who direct agricultural training programs in safe tractor operation and safe farm machinery operation that comply with the United States Department of Labor regulations on hazardous occupations in agriculture. Upon successful completion of these training…

  8. Colliding fragment islands transport independent lineages of endemic rock-crawlers (Grylloblattodea: Grylloblattidae) in the Japanese archipelago.

    PubMed

    Schoville, Sean D; Uchifune, Toshiki; Machida, Ryuichiro

    2013-03-01

    Fragment islands, viewed from the paradigm of island biogeographic theory, depend on continual immigration from continental sources to maintain levels of species diversity, or otherwise undergo a period of relaxation where species diversity declines to a lower equilibrium. Japan is a recently derived fragment island with a rich endemic flora and fauna. These endemic species have been described as paleoendemics, and conversely as recently derived Pleistocene colonists. Geological events in the Miocene period, notably the fragmentation and collision of islands, and the subsequent uplift of mountains in central Japan, provided opportunities for genetic isolation. More recently, cyclical climatic change during the Pliocene and Pleistocene periods led to intermittent land bridge connections to continental Asia. Here we investigate the pattern and timing of diversification in a diverse endemic lineage in order to test whether ongoing migration has sustained species diversity, whether there is evidence of relaxation, and how geological and climatic events are associated with lineage diversification. Using multi-locus genetic data, we test these hypotheses in a poorly dispersing, cold-adapted terrestrial insect lineage (Grylloblattodea: Grylloblattidae) sampled from Japan, Korea, and Russia. In phylogenetic analyses of concatenated data and a species tree approach, we find evidence of three deeply divergent lineages of rock-crawlers in Japan consistent with the pattern of island fragmentation from continental Asia. Tests of lineage diversification rates suggest that relaxation has not occurred and instead endemism has increased in the Japanese Grylloblattidae following mountain-building events in the Miocene. Although the importance of climate change in generating species diversity is a commonly held paradigm in Japanese biogeography, our analyses, including analyses of demographic change and phylogeographic range shifts in putative species, suggests that Pleistocene

  9. Evaluation of a tractor cab using real-time aerosol counting instrumentation.

    PubMed

    Hall, Ronald M; Heitbrink, William A; Reed, Laurence D

    2002-01-01

    Aerosol instrumentation was used to evaluate air infiltration into tractor cabs that are used to protect the agricultural worker during pesticide applications. Preliminary surveys were conducted on three different manufactured agriculture enclosures. The results of these preliminary surveys indicated that aerosols are entering the cab through leak sources or are being generated inside the cab. These results identified the need for in-depth field evaluations of tractor cabs to identify any leak sources. To evaluate the ability of tractor cabs to reduce operator air contaminant exposure, field evaluations were conducted on two tractor cabs. Specifically, we evaluated: 1) the particle size distribution and the effectiveness of the filter system; and 2) air infiltration into the cab. These evaluations were also conducted to demonstrate the ease and practicality of using optical particle counters to evaluate the ability of cabin filtration systems. Pesticide particle size distribution during an air blast spray operation was also evaluated during the study. The field tests were conducted on a John Deere 7000 series tractor cab (tractor manufacturer's cab) and a Nelson spraycab (retrofit cab). Both cabs were equipped with high efficiency particulate air (HEPA) filter media which were assumed to be 99.97 percent efficient at removing the test aerosol, atmospheric condensation nuclei. Thus, the major source of aerosols inside the cab was assumed to be leakage around filters at the seals. Using a portable dust monitor (PDM), the ratio of the outside to inside aerosol measurements was used to calculate a cab protection factor. During the evaluations, one PDM was placed inside the tractor cab (near the tractor operator) and one PDM was placed outside (near the air intake) to count particles. During the evaluations, the instruments were switched to prevent instrument bias from affecting the findings. The ratio of the two measurements (i.e., protection factor = outside

  10. Effect of using GPS autosteer guidance systems on the eye-glance behavior and posture of tractor operators.

    PubMed

    Karimi, D; Henry, J; Mann, D D

    2012-10-01

    Tractor operators are prone to neck and back discomfort and disorders. It is well known that awkward posture is a major contributor to this problem. Previous studies have investigated the prevalence of awkward posture and the resulting discomfort and disorders among tractor operators. They have also suggested various ways to mitigate this problem. With the introduction of new autosteer guidance systems, the tractor operator is relieved from the task of steering the tractor for most of the time during field work. Therefore, it is expected that the operator's posture will change. The goal of this study was to investigate the changes in the eye-glance behavior and posture of tractor operators as a result of using autosteer guidance systems. An eye-tracking system and a camcorder were used to record the eye-glance behavior and posture of 13 tractor operators as they performed seeding operations. The experiment with each operator consisted of two sessions. In one session, the operator used an autosteer system, while in the other session the operator steered the tractor manually. Analysis of the data showed that the eye-glance behavior and posture of the operators were significantly different between the autosteer and manual steering sessions. With the autosteer system, the operators spent less time in an awkward posture, and they changed their posture less frequently. However, even with the autosteer system, the operators spent 1/3 of their time in an awkward posture. Subjective feedback from the operators indicated that more than half of them experienced back or neck/shoulder discomfort during or after seeding. It is essential that the recommendations of the previous studies, such as using large rear-view mirrors or a rotating tractor seat, be evaluated when the operator is using an autosteer system. Other tools, such as video cameras that show the attached equipment, should also be tested to evaluate their effectiveness in reducing the operator's exposure to awkward

  11. a Decade of Improvement in Whole-Body Vibration and Low Back Pain for Freight Container Tractor Drivers

    NASA Astrophysics Data System (ADS)

    Nishiyama, K.; Taoda, K.; Kitahara, T.

    1998-08-01

    The authors' study in 1983 revealed that the whole-body vibration of the tractor units of freight containers was most hazardous in the back-to-chest directions (x-axis). The allowable exposure time was considerably shorter than that for heavy duty trucks. The low back pain (LBP) among the drivers seemed to be due to the long working hours and the ergonomically unsound tractor design, as well as the vibration. A preventative measure was the introduction of a tractor cab suspended by an air spring instead of a steel spring. In 1992, a follow-up field study was conducted. A personal vibration exposure meter developed by us measured the whole-body vibration on eight tractors. Eighty-nine triplets matched with the age and the years of driving tractors answered a questionnaire evaluation of the ergonomics of their tractor units.The comparison of the newest steel suspension vehicles to the old ones produced by the same motor company revealed that in thex-axis the vibration level had decreased by as much as 4 to 9 dB. Some tractors showed an increase in vibration in the buttocks-to-head direction (z-axis). However, such adverse changes seemed not to affect evaluations according to the fatigue-decreased proficiency boundary (FDP) and the exposure limit (EL) recommended in ISO 2631-1978. The present models, regardless of the type of suspension, changed the direction of the most hazardous vibration from thex-axis to thez-axis. However, the effect of the air-suspension was not so remarkable as expected. Among 40% of drivers seemed to exceed the FDP boundary during a day.The questionnaire study showed an improvement in the ergonomic evaluation of the tractors. The air suspension models seemed to induce less LBP than the steel suspension models.

  12. Effect of using GPS autosteer guidance systems on the eye-glance behavior and posture of tractor operators.

    PubMed

    Karimi, D; Henry, J; Mann, D D

    2012-10-01

    Tractor operators are prone to neck and back discomfort and disorders. It is well known that awkward posture is a major contributor to this problem. Previous studies have investigated the prevalence of awkward posture and the resulting discomfort and disorders among tractor operators. They have also suggested various ways to mitigate this problem. With the introduction of new autosteer guidance systems, the tractor operator is relieved from the task of steering the tractor for most of the time during field work. Therefore, it is expected that the operator's posture will change. The goal of this study was to investigate the changes in the eye-glance behavior and posture of tractor operators as a result of using autosteer guidance systems. An eye-tracking system and a camcorder were used to record the eye-glance behavior and posture of 13 tractor operators as they performed seeding operations. The experiment with each operator consisted of two sessions. In one session, the operator used an autosteer system, while in the other session the operator steered the tractor manually. Analysis of the data showed that the eye-glance behavior and posture of the operators were significantly different between the autosteer and manual steering sessions. With the autosteer system, the operators spent less time in an awkward posture, and they changed their posture less frequently. However, even with the autosteer system, the operators spent 1/3 of their time in an awkward posture. Subjective feedback from the operators indicated that more than half of them experienced back or neck/shoulder discomfort during or after seeding. It is essential that the recommendations of the previous studies, such as using large rear-view mirrors or a rotating tractor seat, be evaluated when the operator is using an autosteer system. Other tools, such as video cameras that show the attached equipment, should also be tested to evaluate their effectiveness in reducing the operator's exposure to awkward

  13. Wind-drag estimation in a traffic accident involving a motor scooter and a tractor-trailer.

    PubMed

    Park, Chan-Seong; Jeon, Seung-Won; Lee, Kyu-Jung; Kim, Jun-Suk; Oh, Jae-Geun; Park, Jong-Chan; Lee, Hong-Seok; Choi, Young-Shik

    2012-07-01

    This case report describes a noncontact traffic accident involving a motor scooter and a tractor-trailer with a focus on the wind-drag effect. We used load cells to measure the drag force acting on a substantially similar motor scooter when a substantially similar tractor-trailer passes by it, taking into consideration various speeds of the tractor-trailer and distances between the two vehicles. A three-dimensional steady-state flow analysis was also performed by using the CFX program for computational fluid dynamics to examine the streamlines and the pressure distribution around the tractor-trailer at various speeds. From the experiment, for a separation distance of 1.0 m (3.28 ft) and a speed of 90 km/h (55.9 mph), the maximum resultant drag force is 124.5 N (28 lb); this constitutes a degree of force that could abruptly disrupt the stability in maneuvering by an operator who is unaware of the approaching tractor-trailer. In addition, a single equation that relates the tractor-trailer speed to the drag force that acts on the motor scooter was derived on the basis of the Reynolds number (Re) and the wind-drag coefficient (C(d)): C(d) = 1.298 × 10(-7) Re.

  14. Quantifying driver's field-of-view in tractors: methodology and case study.

    PubMed

    Gilad, Issachar; Byran, Eyal

    2015-01-01

    When driving a car, the visual awareness is important for operating and controlling the vehicle. When operating a tractor, it is even more complex. This is because the driving is always accompanied with another task (e.g., plough) that demands constant changes of body postures, to achieve the needed Field-of-View (FoV). Therefore, the cockpit must be well designed to provide best FoV. Today, the driver's FoV is analyzed mostly by computer simulations of a cockpit model and a Digital Human Model (DHM) positioned inside. The outcome is an 'Eye view' that displays what the DHM 'sees'. This paper suggests a new approach that adds quantitative information to the current display; presented on three tractor models as case studies. Based on the results, the design can be modified. This may assist the engineer, to analyze, compare and improve the design, for better addressing the driver needs. PMID:26327259

  15. Co-Simulation Research of the Mechanical-Hydraulic-Control Coupling System of ITER Tractor

    NASA Astrophysics Data System (ADS)

    Yang, Xiuqing; Luo, Minzhou; Mei, Tao; Yao, Damao

    2009-06-01

    The virtual prototyping models of the mechanical, hydraulic and control system of the ITER tractor were built with CATIA, ADAMS and MATLAB/Simulink respectively according to its heavy load and high precision characteristics, and the data transfer between the different models was accomplished by the integration interface between different software. Consequently the virtual experimental platform for the multi-disciplinary co-simulation was established. A co-simulation study of the mechanical-hydraulic-control coupling system of the ITER tractor was carried out. The synchronization servo control of parallel hydraulic cylinders was implemented, and the tracking control of the preconcerted trajectory of the hydraulic cylinders was realized on the established experimental platform. This paper presents the optimization design and technology rebuilding for the complicated coupling system with its theoretic foundation and co-simulation virtual experimental platform.

  16. Heat-treatment by using induction heating on the Minsk Tractor Plant

    SciTech Connect

    Kosmovich, L.S.; Baranov, V.S.; Koshelenkov, K.N.; Fel'dman, L.Ya.

    1988-01-01

    The Minsk Tractor Plant uses a technique for hardening preceded by induction heating for more than 50% of its heat-treated parts made from 45, 40Kh, 38KhGs, and 33KhS steels. The majority of parts undergo heat-treatment on the machining lines. This method made it possible to develop and put into service an automatic device for strainless hardening of strips in the forced conditions. Improving and introducing this new technological process, equipment, and fittings for heat treatment by induction heating was found to increase the life of the tractor parts, reduce labor costs for their manufacture as well as increase savings in electricity and rolled materials.

  17. Optical pulling force on a magneto-dielectric Rayleigh sphere in Bessel tractor polarized beams

    NASA Astrophysics Data System (ADS)

    Mitri, F. G.; Li, R. X.; Yang, R. P.; Guo, L. X.; Ding, C. Y.

    2016-11-01

    The optical radiation force induced by Bessel (vortex) beams on a magneto-dielectric subwavelength sphere is investigated with particular emphasis on the beam polarization and order l (or topological charge). The analysis is focused on identifying the regions and some of the conditions to achieve retrograde motion of the sphere centered on the axis of wave propagation of the incident beam, or shifted off-axially. Exact non-paraxial analytical solutions are established, and computations for linear, circular, radial, azimuthal and mixed polarizations of the individual plane wave components forming the Bessel (vortex) beams by means of the angular spectrum decomposition method (ASDM) illustrate the theory with particular emphasis on the tractor (i.e. reversal) behavior of the force. This effect results in the pulling of the magneto-dielectric sphere against the forward linear momentum density flux associated with the incoming waves. Should some conditions related to the choice of the beam parameters as well as the permittivity and permeability of the sphere be met, the optical force vanishes and reverses sign. Moreover, the beam polarization is shown to affect differently the axial negative pulling force for either the zeroth- or the first-order Bessel beam. When the sphere is centered on the beam‧s axis, the axial force component is always negative for the zeroth-order Bessel beam except for the radial and azimuthal polarization configurations. Nonetheless, for the first-order Bessel beam, the axial force is negative for the radial polarization case only. Additional tractor beam effects arise when the sphere departs from the center of the beam. It is also demonstrated that the tractor beam effect arises from the force component originating from the cross-interaction between the electric and magnetic dipoles. Potential applications are in particle manipulation, optical levitation, tractor beam tweezers, and other emergent technologies using polarized Bessel beams on

  18. Tractor tire aspect ratio effects on soil bulk density and cone index

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A 580/70R38 tractor drive tire with an aspect ratio of 0.756 and a 650/75R32 tire with an aspect ratio of 0.804 were operated at two dynamic loads and two inflation pressures on a sandy loam and a clay loam with loose soil above a hardpan. Soil bulk density and cone index were measured just above t...

  19. Adoption of rollover protective structures (ROPS) on U.S. farm tractors by state: 1993-1995, 2001, and 2004.

    PubMed

    Hard, D L; Myers, J R

    2011-04-01

    This research compares state-level rollover protective structure (ROPS) prevalence rates from the early and mid-1990s to those observed in the years 2001 and 2004. In addition, state-level ROPS prevalence rates are compared to state-level tractor overturn fatality rates. Tractor data for 1993-1995 and for 2001 and 2004 for all tractors and ROPS-equipped tractors in use on U.S. farms were derived from surveys conducted for NIOSH by the USDA-NASS. Changes in ROPS prevalence rates at the state level between the two time periods were assessed using a two-sample paired t-test with unequal sample sizes. Poisson regression was used to assess the association between ROPS prevalence rates and tractor overturn fatality rates at the state level. Overall, 49 of the 50 states had an observed increase in the percentage of farm tractors equipped with ROPS from 1993-1995 to 2001 and 2004. This increase was statistically significant for 34 states. Large shifts in ROPS prevalence were found within individual states and in clusters of states. These include a major increase in the southeastern U.S. and some western states. However, a core of states in the northeast (many of them in or near the Appalachian Mountains) through the upper midwest remain in the bottom quartile for ROPS prevalence. For the years 1992 through 2004, the highest fatality rates were observed in many of the same states that were identified previously as having persistently low ROPS prevalence rates. There is a clear relationship between low state-level ROPS prevalence rates and high state-specific tractor overturn fatality rates. While progress has been made in increasing the percentage of ROPS-equipped farm tractors, it is projected that ROPS prevalence rates will not reach a protective level nationally until after 2015. Regionally, the northeast and midwest will not reach protective levels of ROPS-equipped tractors until after 2020. Based on the adoption rates observed, tractor overturn rates will likely

  20. Coca-Cola Refreshments Class 8 Diesel Electric Hybrid Tractor Evaluation: 13-Month Final Report

    SciTech Connect

    Walkowicz, K.; Lammert, M.; Curran, P.

    2012-08-01

    This 13-month evaluation used five Kenworth T370 hybrid tractors and five Freightliner M2106 standard diesel tractors at a Coca Cola Refreshments facility in Miami, Florida. The primary objective was to evaluate the fuel economy, emissions, and operational field performance of hybrid electric vehicles when compared to similar-use conventional diesel vehicles. A random dispatch system ensures the vehicles are used in a similar manner. GPS logging, fueling, and maintenance records and laboratory dynamometer testing are used to evaluate the performance of these hybrid tractors. Both groups drive similar duty cycles with similar kinetic intensity (0.95 vs. 0.69), average speed (20.6 vs. 24.3 mph), and stops per mile (1.9 vs. 1.5). The study demonstrated the hybrid group had a 13.7% fuel economy improvement over the diesel group. Laboratory fuel economy and field fuel economy study showed similar trends along the range of KI and stops per mile. Hybrid maintenance costs were 51% lower per mile; hybrid fuel costs per mile were 12% less than for the diesels; and hybrid vehicle total cost of operation per mile was 24% less than the cost of operation for the diesel group.

  1. Aerodynamic performance of a drag reduction device on a full-scale tractor/trailer

    NASA Astrophysics Data System (ADS)

    Lanser, Wendy R.; Ross, James C.; Kaufman, Andrew E.

    1991-09-01

    The effectiveness of an aerodynamic boattail on a tractor/trailer road vehicle was measured in the NASA Ames Research Center 80- by 120-Foot Wind Tunnel. Results are examined for the tractor/trailer with and without the drag reduction device. Pressure measurements and flow visualization show that the aerodynamic boattail traps a vortex or eddy in the corner formed between the device and the rear corner of the trailer. This recirculating flow turns the flow inward as it separates from the edges of the base of the trailer. This modified flow behavior increases the pressure acting over the base area of the truck, thereby reducing the net aerodynamic drag of the vehicle. Drag measurements and pressure distributions in the region of the boattail device are presented for selected configurations. The optimum configuration reduces the overall drag of the tractor/trailer combination by about 10 percent at a zero yaw angle. Unsteady pressure measurements do not indicate strong vortex shedding, although the addition of the boattail plates increases high frequency content of the fluctuating pressure.

  2. Aerodynamic performance of a drag reduction device on a full-scale tractor/trailer

    NASA Technical Reports Server (NTRS)

    Lanser, Wendy R.; Ross, James C.; Kaufman, Andrew E.

    1991-01-01

    The effectiveness of an aerodynamic boattail on a tractor/trailer road vehicle was measured in the NASA Ames Research Center 80- by 120-Foot Wind Tunnel. Results are examined for the tractor/trailer with and without the drag reduction device. Pressure measurements and flow visualization show that the aerodynamic boattail traps a vortex or eddy in the corner formed between the device and the rear corner of the trailer. This recirculating flow turns the flow inward as it separates from the edges of the base of the trailer. This modified flow behavior increases the pressure acting over the base area of the truck, thereby reducing the net aerodynamic drag of the vehicle. Drag measurements and pressure distributions in the region of the boattail device are presented for selected configurations. The optimum configuration reduces the overall drag of the tractor/trailer combination by about 10 percent at a zero yaw angle. Unsteady pressure measurements do not indicate strong vortex shedding, although the addition of the boattail plates increases high frequency content of the fluctuating pressure.

  3. The flow in the gap of a tractor-trailer in the presence of a side wind

    NASA Astrophysics Data System (ADS)

    Hammache, Mustapha; Browand, Fred

    2000-11-01

    The aerodynamic performance of large trucks is greatly influenced by the gap between tractor and trailer and by the presence of a side wind. The present work examines these effects by using a baseline geometry consisting of a 1/15th scale model of an integrated tractor-trailer truck called the Ground Transportation System (GTS). The experiments are conducted in a wind tunnel at a free-stream velocity of 20 m/s, which corresponds to a Reynolds number of approximately 260,000 based on the square-root of the truck’s frontal area. The tractor-trailer is yawed at various angles with respect to the free-stream and the drag and side forces on the tractor and the trailer are measured (separately) as a function of gap spacing and yaw angle. The flow in the gap region is measured with the particle image velocimetry (PIV) technique. The data shows that the lowest drag is achieved at zero gap and no side wind. At small but finite yaw angles, there exists a critical gap spacing at which the flow undergoes a transition that causes a sharp rise in the drag on both tractor and trailer. Different flow states can be established and significant hysteresis effects are observed as the critical gap is approached from higher versus lower values of the gap spacing.

  4. Estimating car driver injury severity in car/tractor-trailer collisions.

    PubMed

    Shao, S P

    1987-06-01

    This paper analyzes road accidents between passenger cars and tractor-trailer rigs occurring in the greater Baltimore-Washington D.C. metropolitan area during the period 1983-84. During this time interval, approximately 1700 such collisions occurred on major highways in the state of Maryland. Traffic accident data is factor analyzed for underlying dimensions related to this accident type. A subsequent prediction analysis is made in order to discern whether injury severity estimations can be made using driver, vehicle, and environmental characteristic variables.

  5. Determination of influence factors and accident rates for the Armored Tractor/Safe Secure Trailer

    SciTech Connect

    Phillips, J.S.; Clauss, D.B.; Blower, D.F.

    1994-04-01

    Operating environments, such as road type, road location, and time of day, play an important role in the observed accident rates of heavy trucks used in general commerce. These same factors influence the accident rate of the Armored Tractor/Safe Secure Trailer (AT/SST) used by the Department of Energy to transport hazardous cargos within the continental United States. This report discusses the development of accident rate influence factors. These factors, based on heavy trucks used in general commerce, are used to modify the observed overall AT/SST accident rate to account for the different operating environments.

  6. The analysis of work-related injuries in a tractor factory.

    PubMed

    Nikoli, N; Mavrić, T

    1994-05-01

    An analysis of work-related injuries and absenteeism was carried out in a steel production and tractor manufacturing factory from 1982 to 1986. During that period there were 1152 injuries and 16,798 working days lost. Foundry workers were the most frequently injured; fists and fingers were the most frequently affected parts of the body. The number of injuries at work as well as the number of lost working days were highly influenced by the low socio-economic position of workers and by a general recession.

  7. Structural dynamics modeling and testing of the Department of Energy tractor/trailer combination

    SciTech Connect

    Field, R.V. Jr.; Hurtado, J.E.; Carne, T.G.; Dohrmann, C.R.

    1996-12-31

    This study presents a combined analytical and experimental effort to characterize and improve the ride quality of the Department of Energy tractor/trailer combination. The focus is to augment the experimental test results with the use of a high quality computer model. The discussion includes an overview of the finite element model of the vehicle and experimental modal test results. System identification techniques are employed to update the mathematical model. The validated model is then used to illustrate the benefits of incorporating two major design changes, namely the switch from a separate cab/sleeper configuration to an integrated cab, and the use of a cab suspension system.

  8. 29 CFR 1926.1000 - Rollover protective structures (ROPS) for material handling equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., rubber-tired dozers, wheel-type agricultural and industrial tractors, crawler tractors, crawler-type... performance criteria detailed in §§ 1926.1001 and 1926.1002, as applicable or shall be designed, fabricated... two times the weight of the prime mover applied at the point of impact. (i) The design objective...

  9. Reduction of aerodynamic drag and fuel consumption for tractor-trailer vehicles

    NASA Technical Reports Server (NTRS)

    Muirhead, V. U.; Saltzman, E. J.

    1979-01-01

    Wind-tunnel tests were performed on a scale model of a cab-over-engine tractor-trailer vehicle and several modifications of the model. Results from two of the model configurations were compared with full-scale drag data obtained from similar configurations during coast-down tests. Reductions in fuel consumption derived from these tests are presented in terms of fuel quantity and dollar savings per vehicle year, based on an annual driving distance of 160,900 km (100,000 mi.). The projected savings varied from 13,001 (3435) to 25,848 (6829) liters (gallons) per year which translated to economic savings from $3435 to about $6829 per vehicle year for an operating speed of 88.5 km/h (55 mph) and wind speeds near the national average of 15.3 km/h (9.5 mph). The estimated cumulative fuel savings for the entire U.S. fleet of cab-over-engine tractor, van-type trailer combinations ranged from 4.18 million kl (26.3 million bbl) per year for a low-drag configuration to approximately twice that amount for a more advanced configuration.

  10. Development and implementation of thermal signature testing protocol of auxiliary power unit (APU) and diesel tractor

    NASA Astrophysics Data System (ADS)

    Jenkins, Chelsea L.; Bourne, Stefanie M.; Rowley, Matthew J.; Miles, Jonathan J.

    2004-04-01

    Thermal signature may be one of the defining factors in determining the applicability of fuel cell auxiliary power unit (APU) technology in military applications. Thermal characterization is important for military applications given that identification and detection may be accomplished through observation of its thermal signature. The operating modes and power takeoff operations of a vehicle will likely determine the thermal profile. The objective of our study was to develop and implement a protocol for quantifying the thermal characteristics of a methanol fuel cell and an idling tractor engine under representative characteristic operations. APU thermal characteristics are a special case for which standardized testing procedures do not presently exist. A customized testing protocol was developed and applied that is specific to an APU-equipped vehicle. Initial testing was conducted on the methanol APU-equipped Freightliner tractor using a high-performance radiometric infrared system. The APU profile calls for a series of infrared images to be collected at three different viewing angles and two different elevations under various loads. The diesel engine was studied in a similar fashion using seven different viewing angles and two different elevations. Raw data collected according to the newly developed methodology provided the opportunity for computer analysis and thermal profiling of both the fuel cell and the diesel engine.

  11. Preventing tractor rollover fatalities: performance of the NIOSH autoROPS.

    PubMed

    Powers, J R; Harris, J R; Etherton, J R; Ronaghi, M; Snyder, K A; Lutz, T J; Newbraugh, B H

    2001-09-01

    Approximately 132 agricultural tractor overturn fatalities occur per year. The use of rollover protective structures (ROPS), along with seat belts, is the best known method for preventing these fatalities. One impediment to ROPS use, however, is low clearance situations, such as orchards and animal confinement buildings. To address the need for ROPS that are easily adapted to low clearance situations, the Division of Safety Research, National Institute for Occupational Safety and Health (NIOSH), developed an automatically deploying, telescoping ROPS (Auto-ROPS). The NIOSH AutoROPS consists of two subsystems. The first is a retractable ROPS that is normally latched in its lowered position for day-to-day use. The second subsystem is a sensor that monitors the operating angle of the tractor. Ifa rollover condition is detected by the sensor, the retracted ROPS will deploy and lock in the full upright position before ground contact. Static load testing and field upset tests of the NIOSH AutoROPS have been conducted in accordance with SAE standard J2194. Additionally, timed trials of the AutoROPS deployment mechanism were completed. The design of the retractable ROPS and sensor, as well as the results of the different testing phases are discussed.

  12. 40 CFR 1037.106 - Exhaust emission standards for CO2 for tractors above 26,000 pounds GVWR.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Emission Standards and Related Requirements § 1037.106 Exhaust emission standards for CO2 for tractors... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Exhaust emission standards for CO2...

  13. 40 CFR 1037.106 - Exhaust emission standards for CO2 for tractors above 26,000 pounds GVWR.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Emission Standards and Related Requirements § 1037.106 Exhaust emission standards for CO2 for tractors... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Exhaust emission standards for CO2...

  14. 40 CFR 1037.106 - Exhaust emission standards for CO2 for tractors above 26,000 pounds GVWR.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Emission Standards and Related Requirements § 1037.106 Exhaust emission standards for CO2 for tractors... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Exhaust emission standards for CO2...

  15. A powered roller/crimper for walk-behind tractors to terminate cover crops in conservation agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Roller/crimper implements have been used in large conservation farming systems to terminate cover crops near maturity and flatten them down to create a mulch through which cash crops can be planted directly into the cover residue. On small farms, tractors are usually small and less powerful relative...

  16. 29 CFR 1928.53 - Protective enclosures for wheel-type agricultural tractors-test procedures and performance...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... in 29 CFR 1928.51(a); (B) The following provisions address soil bank test conditions. (1) The test... specified in 29 CFR 1928.51. (b) Types of tests. All protective enclosures for wheel-type agricultural... following definitions shall apply: W = Tractor weight (see 29 CFR 1928.51(a)) in lb (W ′ in kg); E...

  17. 29 CFR 1928.53 - Protective enclosures for wheel-type agricultural tractors-test procedures and performance...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the weight defined in 29 CFR 1928.51(a); (B) The following provisions address soil bank test... specified in 29 CFR 1928.51. (b) Types of tests. All protective enclosures for wheel-type agricultural... following definitions shall apply: W = Tractor weight (see 29 CFR 1928.51(a)) in lb (W″ in kg); E...

  18. 29 CFR 1928.53 - Protective enclosures for wheel-type agricultural tractors-test procedures and performance...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... in 29 CFR 1928.51(a); (B) The following provisions address soil bank test conditions. (1) The test... specified in 29 CFR 1928.51. (b) Types of tests. All protective enclosures for wheel-type agricultural... following definitions shall apply: W = Tractor weight (see 29 CFR 1928.51(a)) in lb (W ′ in kg); E...

  19. 29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CFR 1928.51. (b) Types of tests. All protective frames for wheel-type agricultural tractors shall be... frame for compliance with the performance requirements of this standard. (2) Field-upset test. A field.... (vii) Rear input energy tests (static, dynamic, or field-upset) need not be performed on frames...

  20. 29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CFR 1928.51. (b) Types of tests. All protective frames for wheel-type agricultural tractors shall be... frame for compliance with the performance requirements of this standard. (2) Field-upset test. A field.... (vii) Rear input energy tests (static, dynamic, or field-upset) need not be performed on frames...

  1. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... The provisions of 29 CFR 1926.1001 for rubber-tired dozers and rubber-tired loaders may be used...) Purpose. When overhead protection is provided on wheel-type agricultural and industrial tractors, the... accidental upset. (2) Applicability. This standard applies to wheel-type agricultural and industrial...

  2. 29 CFR 1928.51 - Roll-over protective structures (ROPS) for tractors used in agricultural operations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... STANDARDS FOR AGRICULTURE Roll-Over Protective Structures § 1928.51 Roll-over protective structures (ROPS..., designed to furnish the power to pull, carry, propel, or drive implements that are designed for agriculture... tractors shall meet the test and performance requirements of 29 CFR 1928.52, 1928.53, or 1926.1002...

  3. 29 CFR 1928.51 - Roll-over protective structures (ROPS) for tractors used in agricultural operations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... STANDARDS FOR AGRICULTURE Roll-Over Protective Structures § 1928.51 Roll-over protective structures (ROPS..., designed to furnish the power to pull, carry, propel, or drive implements that are designed for agriculture... tractors shall meet the test and performance requirements of 29 CFR 1928.52, 1928.53, or 1926.1002...

  4. 29 CFR 1928.51 - Roll-over protective structures (ROPS) for tractors used in agricultural operations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... STANDARDS FOR AGRICULTURE Roll-Over Protective Structures § 1928.51 Roll-over protective structures (ROPS..., designed to furnish the power to pull, carry, propel, or drive implements that are designed for agriculture... tractors shall meet the test and performance requirements of 29 CFR 1928.52, 1928.53, or 1926.1002...

  5. Quantitative Estimate of the Relation Between Rolling Resistance on Fuel Consumption of Class 8 Tractor Trailers Using Both New and Retreaded Tires (SAE Paper 2014-01-2425)

    EPA Science Inventory

    Road tests of class 8 tractor trailers were conducted by the US Environmental Protection Agency on new and retreaded tires of varying rolling resistance in order to provide estimates of the quantitative relationship between rolling resistance and fuel consumption.

  6. Intelligent controller for backing up a tractor-trailer truck using state transition table

    NASA Astrophysics Data System (ADS)

    Enab, Yehia M.

    1997-09-01

    The paper introduces a technique for constructing a look-up table that contains information about selected points in the state space of the nonlinear process to be controlled. The new states to which a specific state point transfers when the process is issued different control commands are registered. The controller designed to make use of the table depends on the heuristic assumption that the behavior of the process at a specific state space point is similar to its behavior at a nearby point provided that the process is issued a similar control command at each state. The table design aspects for reducing the storage requirements and minimizing the computational effort for producing control decisions are investigated. The applicability of the controller is tested for the tractor-trailer truck steering problem backing up at a constant speed. The truck backs up in an environment that contains obstacles to be avoided. Computer simulation of the truck and its controller has demonstrated workability.

  7. On the optimum ride control of a stochastic model of a tractor-semitrailer vehicle

    NASA Astrophysics Data System (ADS)

    ElMadany, M. M.; Samaha, M. E.

    1992-07-01

    A systematic approach based on stochastic optimal control and estimation theories for the optimal design of active suspension systems for a tractor-semitrailer vehicle is presented. The vehicle-road system dynamics combined with the human perception of random vibrations are cast in the standard linear quadratic Gaussian format. The time delays of the stochastic excitation process of the multi-axled vehicle are represented by a first order Padé approximation. The optimal controller/observer is derived which minimizes the mean-squared values of performance variables reflecting the human comfort, cargo safety, suspension working space, roadholding ability and control forces. The advantages of optimally controlled suspension systems over their passive counterparts are indicated.

  8. Acoustical pulling force on rigid spheroids in single Bessel vortex tractor beams

    NASA Astrophysics Data System (ADS)

    Mitri, F. G.

    2015-11-01

    The theoretical formalism for acoustical Bessel vortex (helicoidal) tractor beams and results presented here are the first to demonstrate the emergence of a pulling force of attraction on non-spherical oblate and prolate rigid spheroidal particles centered on the beam's axis of wave propagation. Numerical predictions for the axial acoustic radiation force illustrate the theory with particular emphasis on the aspect ratio of the spheroid, the half-cone angle and order of the beam, as well as the dimensionless size parameter. It is demonstrated here that the Bessel vortex beam parameters may be tailored in such a way that the spheroid is pulled against the forward linear momentum density flux associated with the incoming waves. Those results potentially suggest the use of Bessel vortex beams in the development of emergent technologies for non-contact remote sampling and particle characterization.

  9. Impacts of tug and debris sizes on electrostatic tractor charging performance

    NASA Astrophysics Data System (ADS)

    Hogan, Erik A.; Schaub, Hanspeter

    2015-01-01

    Active debris removal techniques enable relocating noncooperative geosynchronous (GEO) debris objects into graveyard orbits. One proposed method is the electrostatic tractor concept. Here a tug vehicle approaches a target debris object and emits an electron beam onto the debris. The charging that results yields an attractive electrostatic force that is used to tow the debris object into a new orbit. In this study, the impacts of relative sizing between tug and debris on the efficacy of this charge transfer process are considered. By applying a charging model and incorporating nominal, quiet GEO space weather conditions, limitations on the size ratio that preclude charge transfer are identified for different levels of beam energy. The resulting electrostatic forces and impacts on reorbiting performance are studied. The results indicate that a larger tug vehicle will enable the tugging of a broader range of debris sizes, and that the tug size should be roughly as large as the expected debris size.

  10. Aerodynamic drag reduction apparatus for gap-divided bluff bodies such as tractor-trailers

    DOEpatents

    Ortega, Jason M.; Salari, Kambiz

    2006-07-11

    An apparatus for reducing the aerodynamic drag of a bluff-bodied vehicle such as a tractor-trailer in a flowstream, the bluff-bodied vehicle of a type having a leading portion, a trailing portion connected to the leading portion, and a gap between the leading and trailing portions defining a recirculation zone. The apparatus is preferably a baffle assembly, such as a vertical panel, adapted to span a width of the gap between the leading and trailing portions so as to impede cross-flow through the gap, with the span of the baffle assembly automatically adjusting for variations in the gap width when the leading and trailing portions pivot relative to each other.

  11. A statistical description of the types and severities of accidents involving tractor semi-trailers

    SciTech Connect

    Clauss, D.B.; Wilson, R.K.; Blower, D.F.; Campbell, K.L.

    1994-06-01

    This report provides a statistical description of the types and severities of tractor semi-trailer accidents involving at least one fatality. The data were developed for use in risk assessments of hazardous materials transportation. Several accident databases were reviewed to determine their suitability to the task. The TIFA (Trucks Involved in Fatal Accidents) database created at the University of Michigan Transportation Research Institute was extensively utilized. Supplementary data on collision and fire severity, which was not available in the TIFA database, were obtained by reviewing police reports for selected TIFA accidents. The results are described in terms of frequencies of different accident types and cumulative distribution functions for the peak contact velocity, rollover skid distance, fire temperature, fire size, fire separation, and fire duration.

  12. Computational Flow Modeling of a Simplified Integrated Tractor-Trailer Geometry

    SciTech Connect

    Salari, K; McWherter-Payne, M

    2003-09-15

    For several years, Sandia National Laboratories and Lawrence Livermore National Laboratory have been part of a consortium funded by the Department of Energy to improve fuel efficiency of heavy vehicles such as Class 8 trucks through aerodynamic drag reduction. The objective of this work is to demonstrate the feasibility of using the steady Reynolds-Averaged Navier-Stokes (RANS) approach to predict the flow field around heavy vehicles, with special emphasis on the base region of the trailer, and to compute the aerodynamic forces. In particular, Sandia's computational fluid dynamics code, SACCARA, was used to simulate the flow on a simplified model of a tractor-trailer vehicle. The results are presented and compared with NASA Ames experimental data to assess the predictive capability of RANS to model the flow field and predict the aerodynamic forces.

  13. Computational flow modeling of a simplified integrated tractor-trailer geometry.

    SciTech Connect

    McWherter-Payne, Mary Anna; Salari, Kambiz

    2003-09-01

    For several years, Sandia National Laboratories and Lawrence Livermore National Laboratory have been part of a consortium funded by the Department of Energy to improve fuel efficiency of heavy vehicles such as Class 8 trucks through aerodynamic drag reduction. The objective of this work is to demonstrate the feasibility of using the steady Reynolds-Averaged Navier-Stokes (RANS) approach to predict the flow field around heavy vehicles, with special emphasis on the base region of the trailer, and to compute the aerodynamic forces. In particular, Sandia's computational fluid dynamics code, SACCARA, was used to simulate the flow on a simplified model of a tractor-trailer vehicle. The results are presented and compared with NASA Ames experimental data to assess the predictive capability of RANS to model the flow field and predict the aerodynamic forces.

  14. The Effect of Propellers and Nacelles on the Landing Speeds of Tractor Monoplanes

    NASA Technical Reports Server (NTRS)

    Windler, Ray

    1932-01-01

    This paper reports wind-tunnel tests giving the lift coefficients of large-scale wing-nacelle combinations both with and without the propeller. The tests were made to show the effect of nacelles, and idling and stopped propellers on the landing speeds of tractor monoplanes. Four types of nacelles with various cowlings were used in numerous positions with respect to both a Clark Y and a thick airfoil. The effect of both the idling and stopped propeller on lift, and consequently on landing speed, was negligible. A nacelle with exposed engine cylinders when placed directly in front of an airfoil caused a slight reduction in lift, consequently an increase in landing speed, over the condition with the wing alone. With this exception no appreciable effect on landing speed was indicated for any of the other combinations.

  15. Steering a Tractor by Means of an EMG-Based Human-Machine Interface

    PubMed Central

    Gomez-Gil, Jaime; San-Jose-Gonzalez, Israel; Nicolas-Alonso, Luis Fernando; Alonso-Garcia, Sergio

    2011-01-01

    An electromiographic (EMG)-based human-machine interface (HMI) is a communication pathway between a human and a machine that operates by means of the acquisition and processing of EMG signals. This article explores the use of EMG-based HMIs in the steering of farm tractors. An EPOC, a low-cost human-computer interface (HCI) from the Emotiv Company, was employed. This device, by means of 14 saline sensors, measures and processes EMG and electroencephalographic (EEG) signals from the scalp of the driver. In our tests, the HMI took into account only the detection of four trained muscular events on the driver’s scalp: eyes looking to the right and jaw opened, eyes looking to the right and jaw closed, eyes looking to the left and jaw opened, and eyes looking to the left and jaw closed. The EMG-based HMI guidance was compared with manual guidance and with autonomous GPS guidance. A driver tested these three guidance systems along three different trajectories: a straight line, a step, and a circumference. The accuracy of the EMG-based HMI guidance was lower than the accuracy obtained by manual guidance, which was lower in turn than the accuracy obtained by the autonomous GPS guidance; the computed standard deviations of error to the desired trajectory in the straight line were 16 cm, 9 cm, and 4 cm, respectively. Since the standard deviation between the manual guidance and the EMG-based HMI guidance differed only 7 cm, and this difference is not relevant in agricultural steering, it can be concluded that it is possible to steer a tractor by an EMG-based HMI with almost the same accuracy as with manual steering. PMID:22164006

  16. Long hours and fatigue: a survey of tractor-trailer drivers.

    PubMed

    Braver, E R; Preusser, C W; Preusser, D F; Baum, H M; Beilock, R; Ulmer, R

    1992-01-01

    Fatigue and long driving hours have been implicated as risk factors in truck crashes. Under federal regulations, commercial drivers are permitted to drive no more than 10 hours before having an 8-hour break and cannot work more than 70 hours over an 8-day period. Several studies have suggested that violations of these rules are common. A survey of long haul tractor-trailer drivers was conducted to estimate what proportion of drivers report that they regularly violate the hours-of-service rules and to identify the drivers most likely to commit hours-of-service violations. During December 1990 through April 1991, a total of 1,249 drivers were interviewed at truck safety inspection stations, truck stops, and agricultural inspection stations in Connecticut, Florida, Oklahoma, and Oregon. In each state, interviews were conducted during varying periods of the day over the course of seven days at inspection stations. Overall, 89 percent of eligible drivers asked for interviews participated in the survey. According to self-reports, almost three-fourths of the respondents violate hours-of-service rules. About two-thirds of the drivers reported that they routinely drive or work more than the weekly maximum. A primary impetus for violating rules appears to be economic factors, including tight delivery schedules and low payment rates. Many other driver, job, and vehicle characteristics were significantly associated with being an hours-of-service violator. The high prevalence of hours-of-service violations among tractor-trailer drivers is a problem in need of urgent attention. Potential measures to reduce the prevalence of rules violations include more enforcement directed toward carriers, wider use of electronic recorders, and increasing the number of rest areas.

  17. Steering a tractor by means of an EMG-based human-machine interface.

    PubMed

    Gomez-Gil, Jaime; San-Jose-Gonzalez, Israel; Nicolas-Alonso, Luis Fernando; Alonso-Garcia, Sergio

    2011-01-01

    An electromiographic (EMG)-based human-machine interface (HMI) is a communication pathway between a human and a machine that operates by means of the acquisition and processing of EMG signals. This article explores the use of EMG-based HMIs in the steering of farm tractors. An EPOC, a low-cost human-computer interface (HCI) from the Emotiv Company, was employed. This device, by means of 14 saline sensors, measures and processes EMG and electroencephalographic (EEG) signals from the scalp of the driver. In our tests, the HMI took into account only the detection of four trained muscular events on the driver's scalp: eyes looking to the right and jaw opened, eyes looking to the right and jaw closed, eyes looking to the left and jaw opened, and eyes looking to the left and jaw closed. The EMG-based HMI guidance was compared with manual guidance and with autonomous GPS guidance. A driver tested these three guidance systems along three different trajectories: a straight line, a step, and a circumference. The accuracy of the EMG-based HMI guidance was lower than the accuracy obtained by manual guidance, which was lower in turn than the accuracy obtained by the autonomous GPS guidance; the computed standard deviations of error to the desired trajectory in the straight line were 16 cm, 9 cm, and 4 cm, respectively. Since the standard deviation between the manual guidance and the EMG-based HMI guidance differed only 7 cm, and this difference is not relevant in agricultural steering, it can be concluded that it is possible to steer a tractor by an EMG-based HMI with almost the same accuracy as with manual steering.

  18. Silent geographical spread of the H7N9 virus by online knowledge analysis of the live bird trade with a distributed focused crawler

    PubMed Central

    Chen, Chen; Lu, Shan; Du, Pengcheng; Wang, Haiyin; Yu, Weiwen; Song, Huawen; Xu, Jianguo

    2013-01-01

    Unlike those infected by H5N1, birds infected by the newly discovered H7N9 virus have no observable clinical symptoms. Public health workers in China do not know where the public health threat lies. In this study, we used a distributed focused crawler to analyze online knowledge of the live bird trade in first-wave provinces, namely, Jiangsu, Zhejiang, Anhui, and Shanghai, to track the new H7N9 virus and predict its spread. Of the 18 provinces proposed to be at high risk of infection, 10 reported human infections and one had poultry specimens that tested positive. Five provinces (Xinjiang, Yunnan, Guizhou, Shaanxi, and Tibet) as well as Hong Kong, Macao, and Taiwan were proposed to have no risk of H7N9 virus infection from the live bird trade. These data can help health authorities and the public to respond rapidly to reduce damage related to the spread of the virus. PMID:26038450

  19. A Demonstration Project in New York and Virginia: Retrofitting Cost-Effective Roll-over Protective Structures (CROPS) on Tractors.

    PubMed

    Hard, D L; McKenzie, E A; Cantis, D; May, J; Sorensen, J; Bayes, B; Madden, E; Wyckoff, S; Stone, B; Maass, J

    2015-07-01

    The NIOSH cost-effective roll-over protective structure (CROPS) demonstration project sought to determine whether three prototype roll-over protective structures (ROPS) designed to be retrofitted on Ford 8N, Ford 3000, Ford 4000, and Massey Ferguson 135 tractors could be installed in the field and whether they would be acceptable by the intended end users (farmers). There were a total of 50 CROPS. demonstrators (25 in New York and 25 in Virginia), with 45 observers attending the New York CROPS demonstrations and 36 observers attending the Virginia CROPS demonstrations, for a total of 70 participants in New York and 61 in Virginia. The oldest retrofitted tractors were 77 to 62 years old, while the newest retrofitted tractors were 40 to 37 years old. The most frequently retrofitted tractor in the CROPS demonstration project was a Ford 3000 series tractor (n = 19; 38%), followed by Ford 4000 (n = 11; 22%), Massey Ferguson 135 (n = 11; 22%), and Ford 8N (n = 9; 18%). A major issue of CROPS retrofitting was the rear wheel fenders. The effort involved in disassembling the fenders (removing the old bolts was often faster by cutting them with a torch), modifying the fender mounting brackets, and then reinstalling the fenders with the CROPS generally required the most time. In addition, various other semi-permanent equipment attachments, such as front-end loaders, required additional time and effort to fit with the CROPS. Demonstrators were asked to rank the reasons why they had not retrofitted their tractors with ROPS until they had enrolled in the CROPS demonstration program. ROPS "cost too much" was ranked as the primary reason for participants in both states (80% for New York and 88% for Virginia). The second highest ranked reasons were "ROPS wasn't available" for Virginia (80%) and "hassle to find ROPS" for New York (69%). The third highest ranked reasons were "not enough time to find ROPS" for New York (67%) and "hassle to find ROPS" for Virginia (79%). All

  20. A Demonstration Project in New York and Virginia: Retrofitting Cost-Effective Roll-over Protective Structures (CROPS) on Tractors

    PubMed Central

    Hard, David L.; McKenzie, E. A.; Cantis, Douglas; May, John; Sorensen, Julie; Bayes, Barbara; Madden, Erin; Wyckoff, Sherry; Stone, Bruce; Maass, Jimmy

    2015-01-01

    The NIOSH cost-effective roll-over protective structure (CROPS) demonstration project sought to determine whether three prototype roll-over protective structures (ROPS) designed to be retrofitted on Ford 8N, Ford 3000, Ford 4000, and Massey Ferguson 135 tractors could be installed in the field and whether they would be acceptable by the intended end users (farmers). There were a total of 50 CROPS demonstrators (25 in New York and 25 in Virginia), with 45 observers attending the New York CROPS demonstrations and 36 observers attending the Virginia CROPS demonstrations, for a total of 70 participants in New York and 61 in Virginia. The oldest retrofitted tractors were 77 to 62 years old, while the newest retrofitted tractors were 40 to 37 years old. The most frequently retrofitted tractor in the CROPS demonstration project was a Ford 3000 series tractor (n = 19; 38%), followed by Ford 4000 (n = 11; 22%), Massey Ferguson 135 (n = 11; 22%), and Ford 8N (n = 9; 18%). A major issue of CROPS retrofitting was the rear wheel fenders. The effort involved in disassembling the fenders (removing the old bolts was often faster by cutting them with a torch), modifying the fender mounting brackets, and then reinstalling the fenders with the CROPS generally required the most time. In addition, various other semi-permanent equipment attachments, such as front-end loaders, required additional time and effort to fit with the CROPS. Demonstrators were asked to rank the reasons why they had not retrofitted their tractors with ROPS until they had enrolled in the CROPS demonstration program. ROPS “cost too much” was ranked as the primary reason for participants in both states (80% for New York and 88% for Virginia). The second highest ranked reasons were “ROPS wasn’t available” for Virginia (80%) and “hassle to find ROPS” for New York (69%). The third highest ranked reasons were “not enough time to find ROPS” for New York (67%) and “hassle to find ROPS” for Virginia

  1. Calibration and algorithm development for estimation of nitrogen in wheat crop using tractor mounted N-sensor.

    PubMed

    Singh, Manjeet; Kumar, Rajneesh; Sharma, Ankit; Singh, Bhupinder; Thind, S K

    2015-01-01

    The experiment was planned to investigate the tractor mounted N-sensor (Make Yara International) to predict nitrogen (N) for wheat crop under different nitrogen levels. It was observed that, for tractor mounted N-sensor, spectrometers can scan about 32% of total area of crop under consideration. An algorithm was developed using a linear relationship between sensor sufficiency index (SIsensor) and SISPAD to calculate the N app as a function of SISPAD. There was a strong correlation among sensor attributes (sensor value, sensor biomass, and sensor NDVI) and different N-levels. It was concluded that tillering stage is most prominent stage to predict crop yield as compared to the other stages by using sensor attributes. The algorithms developed for tillering and booting stages are useful for the prediction of N-application rates for wheat crop. N-application rates predicted by algorithm developed and sensor value were almost the same for plots with different levels of N applied. PMID:25811039

  2. Calibration and Algorithm Development for Estimation of Nitrogen in Wheat Crop Using Tractor Mounted N-Sensor

    PubMed Central

    Singh, Manjeet; Kumar, Rajneesh; Sharma, Ankit; Singh, Bhupinder; Thind, S. K.

    2015-01-01

    The experiment was planned to investigate the tractor mounted N-sensor (Make Yara International) to predict nitrogen (N) for wheat crop under different nitrogen levels. It was observed that, for tractor mounted N-sensor, spectrometers can scan about 32% of total area of crop under consideration. An algorithm was developed using a linear relationship between sensor sufficiency index (SIsensor) and SISPAD to calculate the Napp as a function of SISPAD. There was a strong correlation among sensor attributes (sensor value, sensor biomass, and sensor NDVI) and different N-levels. It was concluded that tillering stage is most prominent stage to predict crop yield as compared to the other stages by using sensor attributes. The algorithms developed for tillering and booting stages are useful for the prediction of N-application rates for wheat crop. N-application rates predicted by algorithm developed and sensor value were almost the same for plots with different levels of N applied. PMID:25811039

  3. Tractor-trailer crashes in Indiana: a case-control study of the role of truck configuration.

    PubMed

    Braver, E R; Zador, P L; Thum, D; Mitter, E L; Baum, H M; Vilardo, F J

    1997-01-01

    Studies of the crash experience of tractors pulling multiple trailers have reached different conclusions concerning the relationship of truck configuration to crash risk. A previous case-control study found a significant increase in crash risk for double-trailer trucks in the state of Washington. The present case-control study was done of tractor-trailers crashing on Indiana interstates during November 1989-March 1991. Controls were obtained for 25% of the crash sites and were all tractor-trailers passing the crash sites during a traffic observation session one to four weeks following a crash on the same day of the week for 30 minutes at the same time of day. Logistic regression identified day of week, time of day, urban/rural area, and specific highway as significant predictors of controls' truck configuration. This model was applied to the cases to estimate the expected number of double-trailer cases. For all crashes combined, no increased crash risk was observed for doubles (Standardized Crash Ratio (SCR) = 83). Doubles were significantly underinvolved in multiple-vehicle crashes (SCR = 74), crashes on dry roads (SCR = 61), and crashes on wet (other than snow, ice, or slush) roads (SCR = 54). Doubles were significantly overinvolved in crashes on roads with snow, ice, or slush (SCR = 153). Because truck configuration was highly associated with driver age and work operation attributes among trucks in crashes, the absence of control data on these potential confounders precluded definitive assessment of the intrinsic risk of multiple versus single-trailer vehicles.

  4. Heavy and Overweight Vehicle Brake Testing: Five-Axle Combination Tractor-Flatbed Final Report

    SciTech Connect

    Lascurain, Mary Beth; Capps, Gary J; Franzese, Oscar

    2013-10-01

    The Federal Motor Carrier Safety Administration, in coordination with the Federal Highway Administration, sponsored the Heavy and Overweight Vehicle Brake Testing (HOVBT) program in order to provide information about the effect of gross vehicle weight (GVW) on braking performance. Because the Federal Motor Carrier Safety Regulations limit the number of braking system defects that may exist for a vehicle to be allowed to operate on the roadways, the examination of the effect of brake defects on brake performance for increased loads is also relevant. The HOVBT program seeks to provide relevant information to policy makers responsible for establishing load limits, beginning with providing test data for a combination tractor/trailer. This testing was conducted on a five-axle combination vehicle with tractor brakes meeting the Reduced Stopping Distance requirement rulemaking. This report provides a summary of the testing activities, the results of various analyses of the data, and recommendations for future research. Following a complete brake rebuild, instrumentation, and brake burnish, stopping tests were performed from 20 and 40 mph with various brake application pressures (15 psi, 25 psi, 35 psi, 45 psi, 55 psi, and full system pressure). These tests were conducted for various brake conditions at the following GVWs: 60,000, 80,000, 91,000, 97,000, 106,000, and 116,000 lb. The 80,000-lb GVWs included both balanced and unbalanced loads. The condition of the braking system was also varied. To introduce these defects, brakes (none, forward drive axle, or rear trailer axle) were made inoperative. In addition to the stopping tests, performance-based brake tests were conducted for the various loading and brake conditions. Analysis of the stopping test data showed the stopping distance to increase with load (as expected) and also showed that more braking force was generated by the drive axle brakes than the trailer axle brakes. The constant-pressure stopping test data

  5. 30 CFR 57.14130 - Roll-over protective structures (ROPS) and seat belts for surface equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and crawler loaders; (2) Graders; (3) Wheel loaders and wheel tractors; (4) The tractor portion of... wheel attachments; (5) Skid-steer loaders; and (6) Agricultural tractors. (b) ROPS construction. ROPS... CFR 57.9088 (1986 edition) shall be considered in compliance with paragraphs (b) and (h) of...

  6. Propulsion Systems Integration for a `Tractor Beam' Mercury Lightcraft: Liftoff Engine

    NASA Astrophysics Data System (ADS)

    Myrabo, L. N.

    2003-05-01

    Described herein is the concept and propulsion systems integration for a revolutionary beam-propelled shuttle called the ``Mercury'' lightcraft - emphasizing the liftoff engine mode. This one-person, ultra-energetic vehicle is designed to ride `tractor beams' into space, transmitted from a future network of satellite solar power stations. The objective is to create a safe, very low cost (e.g., 1000X below chemical rockets) space transportation system for human life, one that is completely `green' and independent of Earth's limited fossil fuel reserves. The lightcraft's airbreathing combined-cycle engine operates in a rotary pulsed detonation mode PDE for lift-offs and landings; at hypersonic speeds it transitions into a magnetohydrodynamic (MHD) slipstream accelerator mode. For the latter, the transatmospheric flight path is momentarily transformed into an extremely long, electromagnetic ``mass-driver'' channel with an effective `fuel' specific impulse in the range of 6000 to 16,000 seconds. These future single-stage-to-orbit, highly-reusuable vehicles will ride ``Highways of Light,'' accelerating at 3 Gs into space, with their throttles just barely beyond `idle' power.

  7. An investigation of drag reduction for tractor trailer vehicles with air deflector and boattail. Final report

    SciTech Connect

    Muirhead, V.U.

    1981-01-01

    A wind tunnel investigation was conducted to determine the influence of several physical variables on the aerodynamic drag of a trailer model. The physical variables included: a cab mounted wind deflector, boattail on trailer, flow vanes on trailer front, forced transition on trailer, and decreased gap between tractor and trailer. Tests were conducted at yaw angles (relative wind angles) of 0, 5, 10, 20, and 30 degrees and Reynolds numbers of 3.58 x 10 to the 5th power 6.12 x 10 to the 5th power based upon the equivalent diameter of the vehicles. The wind deflector on top of the cab produced a calculated reduction in fuel consumption of about 5 percent of the aerodynamic portion of the fuel budget for a wind speed of 15.3 km/hr (9.5 mph) over a wind angle range of 0 deg to 180 deg and for a vehicle speed of 88.5 km/hr (55 mph). The boattail produced a calculated 7 percent to 8 percent reduction in fuel consumption under the same conditions. The decrease in gap reduced the calculated fuel consumption by about 5 percent of the aerodynamic portion of the fuel budget.

  8. Enhanced fuel efficiency on tractor-trailers using synthetic jet-based active flow control

    NASA Astrophysics Data System (ADS)

    Amitay, Michael; Menicovich, David; Gallardo, Daniele

    2016-04-01

    The application of piezo-electrically-driven synthetic-jet-based active flow control to reduce drag on tractor-trailers was explored experimentally in wind tunnel testing as well as full-scale road tests. Aerodynamic drag accounts for more than 50% of the usable energy at highway speeds, a problem that applies primarily to trailer trucks. Therefore, a reduction in aerodynamic drag results in large saving of fuel and reduction in CO2 emissions. The active flow control technique that is being used relies on a modular system comprised of distributed, small, highly efficient actuators. These actuators, called synthetic jets, are jets that are synthesized at the edge of an orifice by a periodic motion of a piezoelectric diaphragm(s) mounted on one (or more) walls of a sealed cavity. The synthetic jet is zero net mass flux (ZNMF), but it allows momentum transfer to flow. It is typically driven near diaphragm and/or cavity resonance, and therefore, small electric input [O(10W)] is required. Another advantage of this actuator is that no plumbing is required. The system doesn't require changes to the body of the truck, can be easily reconfigured to various types of vehicles, and consumes small amounts of electrical power from the existing electrical system of the truck. Preliminary wind tunnel results showed up to 18% reduction in fuel consumption, whereas road tests also showed very promising results.

  9. Space Weather Influence on Relative Motion Control using the Touchless Electrostatic Tractor

    NASA Astrophysics Data System (ADS)

    Hogan, Erik A.; Schaub, Hanspeter

    2016-09-01

    With recent interest in the use of electrostatic forces for contactless tugging and attitude control of noncooperative objects for orbital servicing and active debris mitigation, the need for a method of remote charge control arises. In this paper, the use of a directed electron beam for remote charge control is considered in conjunction with the relative motion control. A tug vehicle emits an electron beam onto a deputy object, charging it negatively. At the same time, the tug is charged positively due to beam emission, resulting in an attractive electrostatic force. The relative position feedback control between the tug and the passive debris object is studied subject to the charging being created through an electron beam. Employing the nominal variations of the GEO space weather conditions across longitude slots, two electrostatic tugging strategies are considered. First, the electron beam current is adjusted throughout the orbit in order to maximize this resulting electrostatic force. This open-loop control strategy compensates for changes in the nominally expected local space weather environment in the GEO region to adjust for fluctuations in the local plasma return currents. Second, the performance impact of using a fixed electron beam current on the electrostatic tractor is studied if the same natural space weather variations are assumed. The fixed electron beam current shows a minor performance penalty (<5 %) while providing a much simpler implementation that does not require any knowledge of local space weather conditions.

  10. Aerodynamic drag reduction tests on a full-scale tractor-trailer combination with several add-on devices

    NASA Technical Reports Server (NTRS)

    Montoya, L. C.; Steers, L. L.

    1974-01-01

    Aerodynamic drag tests were performed on a conventional cab-over-engine tractor with a 45-foot trailer and five commercially available or potentially available add-on devices using the coast-down method. The tests ranged in velocity from approximately 30 miles per hour to 65 miles per hour and included some flow visualization. A smooth, level runway at Edwards Air Force Base was used for the tests, and deceleration measurements were taken with both accelerometers and stopwatches. An evaluation of the drag reduction results obtained with each of the five add-on devices is presented.

  11. A numerical study of scale effects on performance of a tractor type podded propeller

    NASA Astrophysics Data System (ADS)

    Choi, Jung-Kyu; Park, Hyoung-Gil; Kim, Hyoung-Tae

    2014-06-01

    In this study, the scale effect on the performance of the podded propeller of tractor type is investigated. Turbulent flow computations are carried out for Reynolds numbers increasing progressively from model scale to full scale using the CFD analysis. The result of the flow calculation for model scale Reynolds numbers agrees well with that of the experiment of a large cavitation tunnel. The existing numerical analysis indicates that the performance of the podded propeller blades is mainly influenced by the advance coefficient and relatively little by the Reynolds number. However, the drag of pod housing with propeller in operation is different from that of pod housing without propeller due to the acceleration and swirl of propeller slipstream which is altered by propeller loading as well as the pressure recovery and friction according to Reynolds number, which suggests that the pod housing drag under the condition of propeller in operation is the key factor of the scale effect on the performance between model and full scale podded propellers. The so called `drag ratio', which is the ratio of pod housing drag to total thrust of podded propeller, increases as the advance coefficient increases due to accelerated flow in the slipstream of the podded propeller. However, the increasing rate of the drag ratio reduces continuously as the Reynolds number increases from model to full scale progressively. The contribution of hydrodynamic forces, which acts on the parts composed of the pod housing with propeller operating in various loading conditions, to the thrust and the torque of the total propeller unit are presented for a range of Reynolds numbers from model to full scales.

  12. Vibration energy absorption in the whole-body system of a tractor operator.

    PubMed

    Szczepaniak, Jan; Tanaś, Wojciech; Kromulski, Jacek

    2014-01-01

    Many people are exposed to whole-body vibration (WBV) in their occupational lives, especially drivers of vehicles such as tractor and trucks. The main categories of effects from WBV are perception degraded comfort interference with activities-impaired health and occurrence of motion sickness. Absorbed power is defined as the power dissipated in a mechanical system as a result of an applied force. The vibration-induced injuries or disorders in a substructure of the human system are primarily associated with the vibration power absorption distributed in that substructure. The vibration power absorbed by the exposed body is a measure that combines both the vibration hazard and the biodynamic response of the body. The article presents measurement method for determining vibration power dissipated in the human whole body system called Vibration Energy Absorption (VEA). The vibration power is calculated from the real part of the force-velocity cross-spectrum. The absorbed power in the frequency domain can be obtained from the cross-spectrum of the force and velocity. In the context of the vibration energy transferred to a seated human body, the real component reflects the energy dissipated in the biological structure per unit of time, whereas the imaginary component reflects the energy stored/released by the system. The seated human is modeled as a series/parallel 4-DOF dynamic models. After introduction of the excitation, the response in particular segments of the model can be analyzed. As an example, the vibration power dissipated in an operator has been determined as a function of the agricultural combination operating speed 1.39 - 4.16 ms(-1). PMID:24959797

  13. Using mobile, internet connected deep sea crawlers for spatial and temporal analysis of cold seep ecosystems and the collection of real-time classroom data for extreme environment education.

    NASA Astrophysics Data System (ADS)

    Purser, Autun; Kwasnitschka, Tom; Duda, Alexander; Schwendner, Jakob; Bamberg, Marlene; Sohl, Frank; Doya, Carol; Aguzzi, Jacopo; Best, Mairi; Llovet, Neus Campanya I.; Scherwath, Martin; Thomsen, Laurenz

    2015-04-01

    Cabled internet and power connectivity with the deep sea allow instruments to operate in the deep sea at higher temporal resolutions than was possible historically, with the reliance on battery life and data storage capacities. In addition to the increase in sensor temporal frequency, cabled infrastructures now allow remote access to and control of mobile platforms on the seafloor. Jacobs University Bremen, in combination with collaborators from the Robotic Exploration of Extreme Environments (ROBEX) project, CSIC Barcelona and Ocean Networks Canada have been operating tracked deep sea crawler vehicles at ~890 m depth at the dynamic Barkley Canyon methane seep site, Pacific Canada during the last ~4 years. The vehicle has been able to explore an area of ~50 m radius, allowing repeated visits to numerous microhabitats. Mounting a range of sensors, including temperature, pressure, conductivity, fluorescence, turbidity, flow and methane concentration sensors, as well as various camera systems a large dataset has been compiled. Several methane pockmarks are present in the survey area, and geological, biological and oceanographic changes have been monitored over a range of timescales. Several publications have been produced, and in this presentation we introduce further data currently under analysis. Cabled internet connectivity further allows mobile platforms to be used directly in education. As part of the ROBEX project, researchers and students from both terrestrial and planetary sciences are using the crawler in an ongoing study project. Students are introduced to statistical methods from both fields during the course and in later stages they can plan their own research using the in-situ crawler, and follow the progress of their investigations live, then analyse the collected data using the techniques introduced during the course. Cabled infrastructures offer a unique facility for spatial investigation of extreme ecosystems over time, and for the 'hands on

  14. Tractor Mechanics. Maintaining and Servicing the Cooling System, Learning Activity Packages 34-40; Maintaining and Servicing Hydraulic Systems, Learning Activity Packages 41-48.

    ERIC Educational Resources Information Center

    Clemson Univ., SC. Vocational Education Media Center.

    This series of learning activity packages focuses on two areas of tractor mechanics: (1) maintaining and servicing the cooling system and (2) maintaining and servicing hydraulic systems. Each of the fifteen illustrated learning activity packages follows a typical format: introduction, directions, objectives, learning activities, tools and…

  15. Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings V : Clark Y Biplane Cellule - NACA Cowled Nacelle - Tractor Propeller

    NASA Technical Reports Server (NTRS)

    Valentine, E Floyd

    1935-01-01

    This report is the fifth of a series giving the results obtained from wind tunnel tests on the interference drag and propulsive efficiency of nacelle-propeller-wing combinations. This report gives results of tests of an NACA cowled air-cooled engine nacelle with tractor propeller located in 12 positions with reference to a Clark Y biplane cellule.

  16. Tractor-Maintenance: Operation & Daily Care [and] Servicing Air Cleaner & Lubrication. Student Materials. V. A. III. [V-C-1 through V-C-4].

    ERIC Educational Resources Information Center

    Texas A and M Univ., College Station. Vocational Instructional Services.

    Designed for use by students in vocational agricultural classes, this manual deals with tractor maintenance. Operation and daily care are the topics of the first section. Safety is also covered. In the final part of the manual, servicing the air cleaner and lubricating the engine are discussed. Both sections conclude with a quiz. (PLB)

  17. Characterisation of optimal human driver model and stability of a tractor-semitrailer vehicle system with time delay

    NASA Astrophysics Data System (ADS)

    Liu, Zhaoheng

    2007-07-01

    In this paper, a vehicle/driver close-loop system is studied in order to characterise the inherent model parameters of an optimal human controller for a regulation task (e.g. stabilisation after a wind gust) in articulated vehicle motions. The tractor-semitrailer vehicle model consists of two articulated rigid bodies moving on a horizontal plane with a constant forward speed. The driver establishes his steering control through a time-delayed feedback from current vehicle states with respect to the desired motion. Identification of driver model parameters is achieved through an optimal control approach. The stability of the delayed dynamical system is also studied using a numerical method by computing the eigenvalues near the imaginary axis.

  18. Relative safety of traditional agricultural tractor power take-off (PTO) drivelines compared to fluid power--a review.

    PubMed

    Thomas, R S; Buckmaster, D R

    2003-08-01

    Nearly all tractor PTO arrangements used today consist of a rotating mechanical shaft with two or more universal joints and splined couplings. Although this method of power transfer has been the standard for decades, it continues to be a hazard to farm workers. Commonly, PTO accidents involve the snagging of clothes, resulting in the victim being rapidly and violently drawn into (and around) the rotating shaft. Entanglement injuries are both common and severe in the agricultural workforce, with poor shielding maintenance as a contributing factor. If PTO loads were driven with fluid power, this entanglement hazard would be eliminated. With high-pressure injection injury being the principal hazard, the fluid power alternative appears to pose a lower risk in terms of both frequency of occurrence and severity of injury. PMID:12970954

  19. An approach for modeling the influence of wheel tractor loads and vibration frequencies on soil compaction

    NASA Astrophysics Data System (ADS)

    Verotti, M.; Servadio, P.; Belfiore, N. P.; Bergonzoli, S.

    2012-04-01

    Both soil compaction and ground vibration are forms of environmental degradation that may be understood in the context of the vehicle-soil interaction process considered (Hildebrand et al., 2008). The transit of tractors on agricultural soil is often the main cause of soil compaction increasing. As known, this can be a serious problems for tillage and sowing and therefore the influence of all the affecting factors have been extensively studied in the last decades in order to understand their impact on the biosystem. There are factors related to the climate, namely to the rainfalls and temperature, and many others. Hence, it is not simple to figure out a complete model for predicting an index of compaction, for a given situation. Soil compaction models are important tools for controlling soil compaction due to agricultural field traffic and they are potentially useful technique to provide information concerning correct soil management. By means of such models, strategies and recommendations for prevention of soil compaction may be developed and specific advice may be given to farmers and advisers. In order to predict field wheeled and tracked vehicle performance, some empirical methods, used for off-road vehicle, were applied by Servadio (2010) on agricultural soil. The empirical indexes included, besides the soil strength, the load carried by the tire or track, some technical characteristics of the tire or track of the vehicle (tire or track width, tire or track wheel diameter, unloaded tire section height, number of wheel station in one track, tire deflection, total length of the belt track, the track pitch) as well as the vehicle passes. They have been validated with the tests results of agricultural vehicles over a range of soil in central Italy. Among the parameters which affect soil compaction, the water content of the soil, the axle load and number of vehicle passes proved to be the most important ones. The present paper concerns mainly vehicle

  20. STS-27 Atlantis, Orbiter Vehicle (OV) 104, rolls out to KSC LC pad 39B

    NASA Technical Reports Server (NTRS)

    1988-01-01

    STS-27 Atlantis, Orbiter Vehicle (OV) 104, atop the mobile launcher platform rolls out to Kennedy Space Center (KSC) Launch Complex (LC) pad 39B via the crawler transporter. In this profile view, the tractor tracks of the crawler transporter, the mobile launcher platform, and the underside of OV-104 attached to the external tank (ET) are visible.

  1. Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings III : Clark Y Wing - Various Radial-engine Cowlings - Tractor Propeller

    NASA Technical Reports Server (NTRS)

    Wood, Donald H

    1933-01-01

    This report is the third of a series giving the results obtained in the 20-foot wind tunnel on the interference drag, and propulsive efficiency of nacelle-propeller-wing combinations. The first report gave the results of the tests of an NACA cowled air-cooled engine nacelle with tractor propeller located in 21 positions with reference to a thick wing. The second report gave the results for several engine cowlings and nacelles with tractor propeller located in four positions with reference to same wing. The present report gives results of tests of the same nacelles and cowlings in the same positions with reference to a smaller wing of Clark y section. The lift, drag, and propulsive efficiency were determined at several angles of attack for each cowling and in each nacelle location.

  2. Health risk evaluation of whole-body vibration by ISO 2631-5 and ISO 2631-1 for operators of agricultural tractors and recreational vehicles.

    PubMed

    Park, Min-Soo; Fukuda, Takabumi; Kim, Tae-Gu; Maeda, Setsuo

    2013-01-01

    This paper presents experimental research evaluation of the vibration exposure for the health risk prediction during vehicle operation. The vibration measurements were carried out on a recreational vehicle and two types of agricultural tractors. The vibration levels were measured for different surfaces and vehicle speed conditions. Based on the analysis of the results in the small agricultural tractor operated in the workplace (frameworks), Sed exceeded 0.80 MPa by ISO2631-5:2004, and Av exceeded 0.89 m/s(2) by ISO2631-1:1997. That means that operators driving small agricultural tractors more than 8 h a day have a high probability of adverse health effects. However, the exposure value for the recreational vehicle had Sed < 0.5 MPa by ISO2631-5:2004 and Av < 0.5 m/s(2) by ISO2631-1:1997 on highways and local roads. That means Recreational Vehicle operators driving more than 8 h a day, have a low probability of adverse health effects. Also, for the recreational vehicle, vibration was taken at different speeds (40-60 km/h, 80 km/h, 100-120 km/h). However, the speed change did not appear to affect the vibration dose variation while driving a vehicle on the highway and road. Finally, the health effect index of ISO2631-5:2004 are almost the same as assessment of health effect by ISO2631-1:1997. PMID:23558167

  3. Health risk evaluation of whole-body vibration by ISO 2631-5 and ISO 2631-1 for operators of agricultural tractors and recreational vehicles.

    PubMed

    Park, Min-Soo; Fukuda, Takabumi; Kim, Tae-Gu; Maeda, Setsuo

    2013-01-01

    This paper presents experimental research evaluation of the vibration exposure for the health risk prediction during vehicle operation. The vibration measurements were carried out on a recreational vehicle and two types of agricultural tractors. The vibration levels were measured for different surfaces and vehicle speed conditions. Based on the analysis of the results in the small agricultural tractor operated in the workplace (frameworks), Sed exceeded 0.80 MPa by ISO2631-5:2004, and Av exceeded 0.89 m/s(2) by ISO2631-1:1997. That means that operators driving small agricultural tractors more than 8 h a day have a high probability of adverse health effects. However, the exposure value for the recreational vehicle had Sed < 0.5 MPa by ISO2631-5:2004 and Av < 0.5 m/s(2) by ISO2631-1:1997 on highways and local roads. That means Recreational Vehicle operators driving more than 8 h a day, have a low probability of adverse health effects. Also, for the recreational vehicle, vibration was taken at different speeds (40-60 km/h, 80 km/h, 100-120 km/h). However, the speed change did not appear to affect the vibration dose variation while driving a vehicle on the highway and road. Finally, the health effect index of ISO2631-5:2004 are almost the same as assessment of health effect by ISO2631-1:1997.

  4. EVALUATION OF THE EFFECTIVENESS OF TRUCK EFFICIENCY TECHNOLOGIES IN CLASS 8 TRACTOR-TRAILERS BASED ON A TRACTIVE ENERGY ANALYSIS USING MEASURED DRIVE CYCLE DATA

    SciTech Connect

    LaClair, Tim J; Gao, Zhiming; Fu, Joshua S.; Calcagno, Jimmy; Yun, Jeongran

    2014-01-01

    Quantifying the fuel savings that can be achieved from different truck fuel efficiency technologies for a fleet s specific usage allows the fleet to select the combination of technologies that will yield the greatest operational efficiency and profitability. This paper presents an analysis of vehicle usage in a commercial vehicle fleet and an assessment of advanced efficiency technologies using an analysis of measured drive cycle data for a class 8 regional commercial shipping fleet. Drive cycle measurements during a period of a full year from six tractor-trailers in normal operations in a less-than-truckload (LTL) carrier were analyzed to develop a characteristic drive cycle that is highly representative of the fleet s usage. The vehicle mass was also estimated to account for the variation of loads that the fleet experienced. The drive cycle and mass data were analyzed using a tractive energy analysis to quantify the fuel efficiency and CO2 emissions benefits that can be achieved on class 8 tractor-trailers when using advanced efficiency technologies, either individually or in combination. Although differences exist among class 8 tractor-trailer fleets, this study provides valuable insight into the energy and emissions reduction potential that various technologies can bring in this important trucking application.

  5. An investigation of drag reduction for tractor trailer vehicles with air deflector and boattail. [wind tunnel tests

    NASA Technical Reports Server (NTRS)

    Muirhead, V. U.

    1981-01-01

    A wind tunnel investigation was conducted to determine the influence of several physical variables on the aerodynamic drag of a trailer model. The physical variables included: a cab mounted wind deflector, boattail on trailer, flow vanes on trailer front, forced transition on trailer, and decreased gap between tractor and trailer. Tests were conducted at yaw angles (relative wind angles) of 0, 5, 10, 20, and 30 degrees and Reynolds numbers of 3.58 x 10 to the 5th power 6.12 x 10 to the 5th power based upon the equivalent diameter of the vehicles. The wind deflector on top of the cab produced a calculated reduction in fuel consumption of about 5 percent of the aerodynamic portion of the fuel budget for a wind speed of 15.3 km/hr (9.5 mph) over a wind angle range of 0 deg to 180 deg and for a vehicle speed of 88.5 km/hr (55 mph). The boattail produced a calculated 7 percent to 8 percent reduction in fuel consumption under the same conditions. The decrease in gap reduced the calculated fuel consumption by about 5 percent of the aerodynamic portion of the fuel budget.

  6. Narrative text analysis of accident reports with tractors, self-propelled harvesting machinery and materials handling machinery in Austrian agriculture from 2008 to 2010 - a comparison.

    PubMed

    Mayrhofer, Hannes; Quendler, Elisabeth; Boxberger, Josef

    2014-01-01

    The aim of this study was the identification of accident scenarios and causes by analysing existing accident reports of recognized agricultural occupational accidents with tractors, self-propelled harvesting machinery and materials handling machinery from 2008 to 2010. As a result of a literature-based evaluation of past accident analyses, the narrative text analysis was chosen as an appropriate method. A narrative analysis of the text fields of accident reports that farmers used to report accidents to insurers was conducted to obtain detailed information about the scenarios and causes of accidents. This narrative analysis of reports was made the first time and yielded first insights for identifying antecedents of accidents and potential opportunities for technical based intervention. A literature and internet search was done to discuss and confirm the findings. The narrative text analysis showed that in more than one third of the accidents with tractors and materials handling machinery the vehicle rolled or tipped over. The most relevant accident scenarios with harvesting machinery were being trapped and falling down. The direct comparison of the analysed machinery categories showed that more than 10% of the accidents in each category were caused by technical faults, slippery or muddy terrain and incorrect or inappropriate operation of the vehicle. Accidents with tractors, harvesting machinery and materials handling machinery showed similarities in terms of causes, circumstances and consequences. Certain technical and communicative measures for accident prevention could be used for all three machinery categories. Nevertheless, some individual solutions for accident prevention, which suit each specific machine type, would be necessary.

  7. Development of a Short-Duration Drive Cycle to Represent Long-Term Measured Drive Cycle Data: Evaluation of Truck Efficiency Technologies in Class 8 Tractor Trailers

    SciTech Connect

    LaClair, Tim; Gao, Zhiming; Fu, Joshua; Calcagno, Jimmy; Yun, Jeongran

    2014-12-01

    Quantifying the fuel savings and emissions reductions that can be achieved from truck fuel efficiency technologies for a fleet's specific usage allows the fleet to select a combination of technologies that will yield the greatest operational efficiency and profitability. An accurate characterization of usage for the fleet is critical for such an evaluation; however, short-term measured drive cycle data do not generally reflect overall usage very effectively. This study presents a detailed analysis of vehicle usage in a commercial vehicle fleet and demonstrates the development of a short-duration synthetic drive cycle with measured drive cycle data collected over an extended period of time. The approach matched statistical measures of the vehicle speed with acceleration history and integrated measured grade data to develop a compressed drive cycle that accurately represents total usage. Drive cycle measurements obtained during a full year from six tractor trailers in normal operations in a less-than-truckload carrier were analyzed to develop a synthetic drive cycle. The vehicle mass was also estimated to account for the variation of loads that the fleet experienced. These drive cycle and mass data were analyzed with a tractive energy analysis to quantify the benefits in terms of fuel efficiency and reduced carbon dioxide emissions that can be achieved on Class 8 tractor trailers by using advanced efficiency technologies, either individually or in combination. Although differences exist between Class 8 tractor trailer fleets, this study provides valuable insight into the energy and emissions reduction potential that various technologies can bring in this important trucking application. Finally, the methodology employed for generating the synthetic drive cycle serves as a rigorous approach to develop an accurate usage characterization that can be used to effectively compress large quantities of drive cycle data.

  8. Development of a Short-Duration Drive Cycle to Represent Long-Term Measured Drive Cycle Data: Evaluation of Truck Efficiency Technologies in Class 8 Tractor Trailers

    DOE PAGESBeta

    LaClair, Tim; Gao, Zhiming; Fu, Joshua; Calcagno, Jimmy; Yun, Jeongran

    2014-12-01

    Quantifying the fuel savings and emissions reductions that can be achieved from truck fuel efficiency technologies for a fleet's specific usage allows the fleet to select a combination of technologies that will yield the greatest operational efficiency and profitability. An accurate characterization of usage for the fleet is critical for such an evaluation; however, short-term measured drive cycle data do not generally reflect overall usage very effectively. This study presents a detailed analysis of vehicle usage in a commercial vehicle fleet and demonstrates the development of a short-duration synthetic drive cycle with measured drive cycle data collected over an extendedmore » period of time. The approach matched statistical measures of the vehicle speed with acceleration history and integrated measured grade data to develop a compressed drive cycle that accurately represents total usage. Drive cycle measurements obtained during a full year from six tractor trailers in normal operations in a less-than-truckload carrier were analyzed to develop a synthetic drive cycle. The vehicle mass was also estimated to account for the variation of loads that the fleet experienced. These drive cycle and mass data were analyzed with a tractive energy analysis to quantify the benefits in terms of fuel efficiency and reduced carbon dioxide emissions that can be achieved on Class 8 tractor trailers by using advanced efficiency technologies, either individually or in combination. Although differences exist between Class 8 tractor trailer fleets, this study provides valuable insight into the energy and emissions reduction potential that various technologies can bring in this important trucking application. Finally, the methodology employed for generating the synthetic drive cycle serves as a rigorous approach to develop an accurate usage characterization that can be used to effectively compress large quantities of drive cycle data.« less

  9. Wind-Tunnel Tests of Several Model Tractor-Propeller and Pusher-Propeller Wing Extension-Shaft Arrangements, Special Report

    NASA Technical Reports Server (NTRS)

    Harmon, Hubert N.

    1941-01-01

    Tests were made in the 20-foot propeller-research tunnel to investigate the possibility of obtaining increased net efficiencies of propeller-nacelle units by enclosing the engines in the wings and by using extension shafts. A wing of 5-foot chord was fitted with a propeller drive assembly providing for several axial locations of tractor propellers and pusher propellers. A three-blade 4-foot propeller and a three-blade 3 1/2-foot propeller of special design were tested in this wing with spinners and fairings ranging in diameter from 6 to 16 inches. A 16-inch NACA cowling was tested for comparative purposes. Two types of cuffs were also employed. It was found that the net efficiency of a conventional round-shank propeller mounted on an extension shaft in front of or behind a wing increased with an increase in the diameter of the spinner and the shaft housing within the scope of the tests. The largest spinner used had a diameter that might favorably compare with that of a radial engine cowling. The efficiencies for the pusher position appeared to be more critically affected by spinner size than those for the tractor position. The spinners with large diameters for the pusher position resulted in a higher efficiency than those for the corresponding tractor arrangements; the reverse was true for the small spinners. The use of propeller cuffs in combination with a spinner of small diameter generally resulted in net efficiencies that were comparable with those found for the large-spinner combinations.

  10. An Analysis of Once-per-revolution Oscillating Aerodynamic Thrust Loads on Single-Rotation Propellers on Tractor Airplanes at Zero Yaw

    NASA Technical Reports Server (NTRS)

    Rogallo, Vernon L; Yaggy, Paul F; Mccloud, John L , III

    1956-01-01

    A simplified procedure is shown for calculating the once-per-revolution oscillating aerodynamic thrust loads on propellers of tractor airplanes at zero yaw. The only flow field information required for the application of the procedure is a knowledge of the upflow angles at the horizontal center line of the propeller disk. Methods are presented whereby these angles may be computed without recourse to experimental survey of the flow field. The loads computed by the simplified procedure are compared with those computed by a more rigorous method and the procedure is applied to several airplane configurations which are believed typical of current designs. The results are generally satisfactory.

  11. The U.S. Department of Labor's Tractor and Machinery Certification Program: management styles and perceptions held by community stakeholders and instructors.

    PubMed

    Jepsen, S D

    2012-07-01

    A mixed-mode, descriptive study was conducted on the U.S. Department of Labor's (DOL) Tractor and Machinery Certification Program. Legislated by the Fair Labors Standards Act, the Hazardous Occupations Order in Agriculture (HOOA) was enacted in 1968 as a public policy measure to reduce the number of injuries to youth on farms. An educational exemption allows youth 14 and 15 years of age to work for hire after they successfully complete a training program. In the 40+ years since the legislation went into effect prescribing such training exemptions, deficiencies and variations have occurred in the quality of the educational program and the system by which agencies certify young people. To gain a better understanding of the DOL Tractor and Machinery Certification program, community stakeholders were asked to identify management practices, curriculum resources, and perceptions of the DOL program. The study design used qualitative data from 49 agricultural representatives participating in regional focus groups and quantitative data from 330 community instructors responding to an electronic-formatted questionnaire (representing a 70.7% response rate) in an effort to answer the question: "What is the current status of the DOL Tractor and Machinery Certification program in the United States?" The findings revealed that 55.2% of the instructors taught a qualifying DOL program. Of these, the certification was administered through an Extension or 4-H program (68.7%), an agricultural education program (24.7%), or as a combination of Extension and agricultural education (6.0%). Course instructors believed the training was beneficial to students and had opportunity to attract more students than currently enrolled These instructors placed a higher value on standardized teaching materials than on standardized testing procedures; they also supported the need for additional teaching aids, which included hands-on activities, videotapes, student workbooks, and DVDs. Study participants

  12. Prediction of the effects of propeller operation on the static longitudinal stability of single-engine tractor monoplanes with flaps retracted

    NASA Technical Reports Server (NTRS)

    Weil, Joseph; Sleeman, William C , Jr

    1949-01-01

    The effects of propeller operation on the static longitudinal stability of single-engine tractor monoplanes are analyzed, and a simple method is presented for computing power-on pitching-moment curves for flap-retracted flight conditions. The methods evolved are based on the results of powered-model wind-tunnel investigations of 28 model configurations. Correlation curves are presented from which the effects of power on the downwash over the tail and the stabilizer effectiveness can be rapidly predicted. The procedures developed enable prediction of power-on longitudinal stability characteristics that are generally in very good agreement with experiment.

  13. A Summary of the Experimental Results for a Generic Tractor-Trailer in the Ames Research Center 7- by 10-Foot and 12-Foot Wind Tunnels

    NASA Technical Reports Server (NTRS)

    Storms, Bruce L.; Satran, Dale R.; Heineck, James T.; Walker, Stephen M.

    2006-01-01

    Experimental measurements of a generic tractor-trailer were obtained in two wind tunnels at Ames Research Center. After a preliminary study at atmospheric conditions in the 7- by 10-Foot Wind Tunnel, additional testing was conducted at Reynolds numbers corresponding to full-scale highway speeds in the 12-Foot Pressure Wind Tunnel. To facilitate computational modeling, the 1:8-scale geometry, designated the Generic Conventional Model, included a simplified underbody and omitted many small-scale details. The measurements included overall and component forces and moments, static and dynamic surface pressures, and three-component particle image velocimetry. This summary report highlights the effects of numerous drag reduction concepts and provides details of the model installation in both wind tunnels. To provide a basis for comparison, the wind-averaged drag coefficient was tabulated for all configurations tested. Relative to the baseline configuration representative of a modern class-8 tractor-trailer, the most effective concepts were the trailer base flaps and trailer belly box providing a drag-coefficient reduction of 0.0855 and 0.0494, respectively. Trailer side skirts were less effective yielding a drag reduction of 0.0260. The database of this experimental effort is publicly available for further analysis.

  14. Test, Evaluation, and Demonstration of Practical Devices/Systems to Reduce Aerodynamic Drag of Tractor/Semitrailer Combination Unit Trucks

    SciTech Connect

    Scott Smith; Karla Younessi; Matt Markstaller; Dan Schlesinger; Bhaskar Bhatnagar; Donald Smith; Bruno Banceu; Ron Schoon; V.K. Sharma; Mark Kachmarsky; Srikant Ghantae; Michael Sorrels; Conal Deedy; Justin Clark; Skip Yeakel; Michael D. Laughlin; Charlotte Seigler; Sidney Diamond

    2007-04-30

    Class 8 heavy-duty trucks account for over three-quarters of the total diesel fuel used by commercial trucks (trucks with GVWRs more than 10,000 pounds) in the United States each year. At the highway speeds at which these trucks travel (i.e., 60 mph or greater), aerodynamic drag is a major part of total horsepower needed to move the truck down the highway, Reductions in aerodynamic drag can yield measurable benefits in fuel economy through the use of relatively inexpensive and simple devices. The goal of this project was to examine a number of aerodynamic drag reduction devices and systems and determine their effectiveness in reducing aerodynamic drag of Class 8 tractor/semitrailer combination-units, thus contributing to DOE's goal of reducing transportation petroleum use. The project team included major heavy truck manufacturers in the United States, along with the management and industry expertise of the Truck Manufacturers Association as the lead investigative organization. The Truck Manufacturers Association (TMA) is the national trade association representing the major North American manufacturers of Class 6-8 trucks (GVWRs over 19,500 lbs). Four major truck manufacturers participated in this project with TMA: Freightliner LLC; International Truck and Engine Corporation; Mack Trucks Inc.; and Volvo Trucks North America, Inc. Together, these manufacturers represent over three-quarters of total Class 8 truck sales in the United States. These four manufacturers pursued complementary research efforts as part of this project. The project work was separated into two phases conducted over a two-year period. In Phase I, candidate aerodynamic devices and systems were screened to focus research and development attention on devices that offered the most potential. This was accomplished using full-size vehicle tests, scale model tests, and computational fluid dynamics analyses. In Phase II, the most promising devices were installed on full-size trucks and their effect on

  15. Design of a new sensor for determination of the effects of tractor field usage in southern Spain: soil sinkage and alterations in the cone index and dry bulk density.

    PubMed

    Valera, Diego L; Gil, Jesús; Agüera, Juan

    2012-01-01

    Variations in sinkage and cone index are of crucial importance when planning fieldwork, and for determining the trafficability of farm machinery. Many studies have highlighted the link between higher values of these parameters and dramatic decreases in crop yield. Variations in the dry bulk density and cone index of clayey soil in Southern Spain were measured following each of five successive passes over the same land with the three types of tractor most widely used in the area (tracked, two-wheel drive and four-wheel drive). In addition, sinkage (rut depth) of the running gear was measured using a laser microrelief profile meter. This device, which integrates three sensors, was specifically designed for these experiments, as was an electrical penetrometer to determine the cone index, and both instruments proved reliable and accurate in the field. The main goal of this study was to design, manufacture and test these new devices. The first pass caused most soil alteration when compared to successive passes for all types of tractor tested and soil conditions prevailing during the tests. (Heavier) four-wheel drive tractors were found to cause greater soil damage (sinkage, cone index and dry bulk density) than two-wheel drive and track tractors. There was no statistically significant difference between the two latter types. The greatest alterations were recorded in the top 10 cm of the soil. The results show that soil compaction should be avoided as much as possible. This can be achieved by ensuring that tractors always travel along the same tracks, especially in the wet season. At present these aspects are not considered by farmers in this area. PMID:23202006

  16. Design of a New Sensor for Determination of the Effects of Tractor Field Usage in Southern Spain: Soil Sinkage and Alterations in the Cone Index and Dry Bulk Density

    PubMed Central

    Valera, Diego L.; Gil, Jesús; Agüera, Juan

    2012-01-01

    Variations in sinkage and cone index are of crucial importance when planning fieldwork, and for determining the trafficability of farm machinery. Many studies have highlighted the link between higher values of these parameters and dramatic decreases in crop yield. Variations in the dry bulk density and cone index of clayey soil in Southern Spain were measured following each of five successive passes over the same land with the three types of tractor most widely used in the area (tracked, two-wheel drive and four-wheel drive). In addition, sinkage (rut depth) of the running gear was measured using a laser microrelief profile meter. This device, which integrates three sensors, was specifically designed for these experiments, as was an electrical penetrometer to determine the cone index, and both instruments proved reliable and accurate in the field. The main goal of this study was to design, manufacture and test these new devices. The first pass caused most soil alteration when compared to successive passes for all types of tractor tested and soil conditions prevailing during the tests. (Heavier) four-wheel drive tractors were found to cause greater soil damage (sinkage, cone index and dry bulk density) than two-wheel drive and track tractors. There was no statistically significant difference between the two latter types. The greatest alterations were recorded in the top 10 cm of the soil. The results show that soil compaction should be avoided as much as possible. This can be achieved by ensuring that tractors always travel along the same tracks, especially in the wet season. At present these aspects are not considered by farmers in this area. PMID:23202006

  17. A Statistical Description of the Types and Severities of Accidents Involving Tractor Semi-Trailers, Updated Results for 1992-1996

    SciTech Connect

    BLOWER,DANIEL F.; CLAUSS,DAVID B.

    1999-10-01

    This report provides a statistical description of the types and severities of tractor semi-trailer accidents involving at least one fatality. The data were developed for use in risk assessments of hazardous materials transportation. A previous study (SAND93-2580) reviewed the availability of accident data, identified the TIFA (Trucks Involved in Fatal Accidents) as the best source of accident data for accidents involving heavy trucks, and provided statistics on accident data collected between 1980 and 1990. The current study is an extension of the previous work and describes data collected for heavy truck accidents occurring between 1992 and 1996. The TIFA database created at the University of Michigan Transportation Research Institute was extensively utilized. Supplementary data on collision and fire severity, which was not available in the TIFA database, were obtained by reviewing police reports and interviewing responders and witnesses for selected TEA accidents. The results are described in terms of frequencies of different accident types and cumulative distribution functions for the peak contact velocity, rollover skid distance, effective fire temperature, fire size, fire separation, and fire duration.

  18. Methodologies for Crawler Based Web Surveys.

    ERIC Educational Resources Information Center

    Thelwall, Mike

    2002-01-01

    Describes Web survey methodologies used to study the content of the Web, and discusses search engines and the concept of crawling the Web. Highlights include Web page selection methodologies; obstacles to reliable automatic indexing of Web sites; publicly indexable pages; crawling parameters; and tests for file duplication. (Contains 62…

  19. An Intelligent Crawler for a Virtual World

    ERIC Educational Resources Information Center

    Eno, Joshua

    2010-01-01

    Virtual worlds, which allow users to create and interact with content in a 3D, multi-user environment, growing and becoming more integrated with the traditional flat web. However, little is empirically known about the content users create in virtual world and how it can be indexed and searched effectively. In order to gain a better understanding…

  20. 49 CFR 393.130 - What are the rules for securing heavy vehicles, equipment and machinery?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... transportation of heavy vehicles, equipment and machinery which operate on wheels or tracks, such as front end loaders, bulldozers, tractors, and power shovels and which individually weigh 4,536 kg (10,000 lb.) or... heavy vehicles, equipment or machinery with crawler tracks or wheels. (1) In addition to...

  1. 49 CFR 393.130 - What are the rules for securing heavy vehicles, equipment and machinery?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... transportation of heavy vehicles, equipment and machinery which operate on wheels or tracks, such as front end loaders, bulldozers, tractors, and power shovels and which individually weigh 4,536 kg (10,000 lb.) or... heavy vehicles, equipment or machinery with crawler tracks or wheels. (1) In addition to...

  2. 49 CFR 393.130 - What are the rules for securing heavy vehicles, equipment and machinery?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... transportation of heavy vehicles, equipment and machinery which operate on wheels or tracks, such as front end loaders, bulldozers, tractors, and power shovels and which individually weigh 4,536 kg (10,000 lb.) or... heavy vehicles, equipment or machinery with crawler tracks or wheels. (1) In addition to...

  3. 49 CFR 393.130 - What are the rules for securing heavy vehicles, equipment and machinery?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... transportation of heavy vehicles, equipment and machinery which operate on wheels or tracks, such as front end loaders, bulldozers, tractors, and power shovels and which individually weigh 4,536 kg (10,000 lb.) or... heavy vehicles, equipment or machinery with crawler tracks or wheels. (1) In addition to...

  4. Tractor Mechanics. Maintaining and Servicing the Power Train, Learning Activity Packages 49-53; Maintaining and Servicing the Clutch, Learning Activity Packages 54-59; Maintaining and Servicing the Transmission and Differential, Learning Activity Packages 60-68; Maintaining and Servicing the Final Drive, Learning Activity Packages 69-77.

    ERIC Educational Resources Information Center

    Clemson Univ., SC. Vocational Education Media Center.

    This series of learning activity packages focuses on four areas of tractor mechanics: (1) maintaining and servicing the power train, (2) maintaining and servicing the clutch, (3) maintaining and servicing the transmission and differential, and (4) maintaining and servicing the final drive. Each of the twenty-nine illustrated learning activity…

  5. Tractor Hydraulics. A Teaching Reference.

    ERIC Educational Resources Information Center

    American Association for Vocational Instructional Materials, Athens, GA.

    The manual was developed to help provide a better understanding of how and why hydraulic principles serve the purposes of weight reduction, increase of physical effort, and more precise control to machines of all types. The four components that are necessary to have a workable hydraulic system--a reservoir, a pump, a valve, and a motor (cylinder)…

  6. KSC-04PD-2134

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. A tractor-trailer arrives at the Crawler Transporter (CT) area with a new shipment of crawler shoes. The new shoes were manufactured by ME Global in Duluth, Minn. The CT transports the Mobile Launcher Platform, with the assembled Space Shuttle aboard, between the refurbishment area, the VAB and Launch Complex Pads 39A and 39B. The crawlers have 456 shoes, 57 per belt (8 belts in all). Each shoe weighs 2,200 pounds. The original shoes were manufactured for the Apollo Program. Cracks appeared in the shoes in recent years spurring a need for replacement. The new manufacturer, in Duluth, Minn., has improved the design for Return to Flight and use through the balance of the Space Shuttle Program.

  7. KSC-04PD-2135

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. A tractor-trailer arrives at the Crawler Transporter (CT) area with a new shipment of crawler shoes. In the background is the Vehicle Assembly Building. The new shoes were manufactured by ME Global in Duluth, Minn. The CT transports the Mobile Launcher Platform, with the assembled Space Shuttle aboard, between the refurbishment area, the VAB and Launch Complex Pads 39A and 39B. The crawlers have 456 shoes, 57 per belt (8 belts in all). Each shoe weighs 2,200 pounds. The original shoes were manufactured for the Apollo Program. Cracks appeared in the shoes in recent years spurring a need for replacement. The new manufacturer, in Duluth, Minn., has improved the design for Return to Flight and use through the balance of the Space Shuttle Program.

  8. Pipe inspection using the pipe crawler. Innovative technology summary report

    SciTech Connect

    1999-05-01

    The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned.

  9. 29 CFR 1910.180 - Crawler locomotive and truck cranes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., mounted on a base or car equipped for travel on railroad track. It may be self-propelled or propelled by... on a locomotive crane car, which can be connected to the track. (33) Reeving means a rope system in... pound-feet net stabilizing moment about the rail, which shall be minimum with such booms. (ii)...

  10. 29 CFR 1910.180 - Crawler locomotive and truck cranes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., mounted on a base or car equipped for travel on railroad track. It may be self-propelled or propelled by... on a locomotive crane car, which can be connected to the track. (33) Reeving means a rope system in... pound-feet net stabilizing moment about the rail, which shall be minimum with such booms. (ii)...

  11. 29 CFR 1910.180 - Crawler locomotive and truck cranes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., mounted on a base or car equipped for travel on railroad track. It may be self-propelled or propelled by... on a locomotive crane car, which can be connected to the track. (33) Reeving means a rope system in... pound-feet net stabilizing moment about the rail, which shall be minimum with such booms. (ii)...

  12. 29 CFR 1910.180 - Crawler locomotive and truck cranes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., mounted on a base or car equipped for travel on railroad track. It may be self-propelled or propelled by... on a locomotive crane car, which can be connected to the track. (33) Reeving means a rope system in... pound-feet net stabilizing moment about the rail, which shall be minimum with such booms. (ii)...

  13. 29 CFR 1910.180 - Crawler locomotive and truck cranes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., mounted on a base or car equipped for travel on railroad track. It may be self-propelled or propelled by... on a locomotive crane car, which can be connected to the track. (33) Reeving means a rope system in... pound-feet net stabilizing moment about the rail, which shall be minimum with such booms. (ii)...

  14. Tank 19F Folding Crawler Final Evaluation, Rev. 0

    SciTech Connect

    Nance, T.

    2000-10-25

    The Department of Energy (DOE) is committed to removing millions of gallons of high-level radioactive waste from 51 underground waste storage tanks at the Savannah River Site (SRS). The primary radioactive waste constituents are strontium, plutonium,and cesium. It is recognized that the continued storage of this waste is a risk to the public, workers, and the environment. SRS was the first site in the DOE complex to have emptied and operationally closed a high-level radioactive waste tank. The task of emptying and closing the rest of the tanks will be completed by FY28.

  15. A new twist on old ideas: How sitting reorients crawlers

    PubMed Central

    Soska, Kasey C.; Robinson, Scott R.; Adolph, Karen E.

    2014-01-01

    Traditionally, crawling and sitting are considered distinct motor behaviors with different postures and functions. Ten- to 12-month-old infants were observed in the laboratory or in their homes while being coaxed to crawl continuously over long, straight walkways (Study 1; N = 20) and during spontaneous crawling during free play (Study 2; N = 20). In every context, infants stopped crawling to sit 3-6 times per minute. Transitions from crawling to sitting frequently turned infants’ bodies away from the direction of heading; subsequent transitions back to crawling were offset by as much as 180° from the original direction of heading. Apparently, body reorientations result from the biomechanics of transitioning between crawling and sitting. Findings indicate that sustained, linear crawling is likely an epiphenomenon of how gait is studied in standard paradigms. Postural transitions between crawling and sitting are ubiquitous and can represent a functional unit of action. These transitions and the accompanying body reorientations likely have cascading effects for infants’ exploration, visual perception, and spatial cognition. PMID:25041056

  16. Optical tractor beam with chiral light

    NASA Astrophysics Data System (ADS)

    Fernandes, David E.; Silveirinha, Mário G.

    2015-06-01

    We suggest a novel mechanism to induce the motion of a chiral material body towards an optical source with no optical traps. Our solution is based on the interference between a chiral light beam and its reflection on an opaque mirror. Surprisingly, it is theoretically shown that the electromagnetic response of the material may be tailored in such a way that independent of the specific body location with respect to the mirror, it is always pulled upstream against the photon flow associated with the incoming wave. Moreover, it is proven that by controlling the handedness of the incoming light it may be possible to harness the sign of the optical force, switching from a pulling force to a pushing force.

  17. Linear tractor dry coal extrusion pump

    SciTech Connect

    Sprouse, Kenneth M.; Matthews, David R.

    2011-10-18

    A pump for transporting particulate material includes an inlet, an outlet, a passageway, a first and second load beam, a first and second scraper seal, and a first and second drive assembly. The inlet introduces the particulate material into the passageway and the outlet expels the particulate material from the passageway. The passageway is defined by a first belt assembly and a second belt assembly that are opposed to each other. The first and second load beams are positioned within the first belt assembly and the second belt assembly, respectively. The first scraper seal and a second scraper seal are positioned proximate the passageway and the outlet. The first drive assembly is positioned within an interior section of the first belt assembly and drives the first belt assembly and the second drive assembly is positioned within an interior section of the second belt assembly and drives the second belt assembly.

  18. Linear tractor dry coal extrusion pump

    DOEpatents

    Sprouse, Kenneth M.; Matthews, David R.

    2008-06-17

    A pump for transporting particulate material includes an inlet, an outlet, a passageway, a first and second load beam, a first and second scraper seal, and a first and second drive assembly. The inlet introduces the particulate material into the passageway and the outlet expels the particulate material from the passageway. The passageway is defined by a first belt assembly and a second belt assembly that are opposed to each other. The first and second load beams are positioned within the first belt assembly and the second belt assembly, respectively. The first scraper seal and a second scraper seal are positioned proximate the passageway and the outlet. The first drive assembly is positioned within an interior section of the first belt assembly and drives the first belt assembly and the second drive assembly is positioned within an interior section of the second belt assembly and drives the second belt assembly.

  19. Optical Pulling Force and Tractor Beams

    NASA Astrophysics Data System (ADS)

    Paul, Nayan Kumar

    Light-matter interaction has been an interesting subject of intense analytical and experimental research since the formulation of Maxwell's electromagnetic wave theory. Optical forces exerted on particles excited by incident light waves have been studied for the last few decades. The interaction of light with materials gives rise to light scattering from the particle in the form of energy. The divergence of the Maxwell stress tensor provides a good approximation of the total optical forces on a particle. The divergence of the stress tensor is mathematically equal to the time average Lorentz force since [special characters omitted]. Others have claimed that the stress tensor is "fraught with danger," but it is a matter of application. The stress tensor approach is computationally simpler since application of the divergence theorem allows for a reduction of dimension in the integration. For example, you can either integrate the force density over the volume of an object (3-D), or integrate the divergence of the stress tensor on a surface (2-D) enclosing the volume. It gives a straightforward prediction of the total optical forces on a particle, but may be challenging in the case of multiple particles or for larger particles. The Rayleigh approximation estimates the radiation pressure on small particles in the propagation direction of light, but may be inappropriate for larger particles in comparison to the wavelength of the incident light waves. Light waves exert radiation pressure on a particle and pushes it away from the light source toward the direction of propagation. It is shown that plane waves propagating in a rectangular waveguide not only push a passive particle toward the propagation direction, but also pull it toward the light source. The particle remains trapped in the transverse direction of the rectangular waveguide. The Lorentz force and the Rayleigh approximation are applied to calculate the total force on the particle. The push-pull phenomenon depends on the frequency of the incident light wave. Optical pulling of a spherical Rayleigh particle along the surface of a dielectric slab waveguide is also shown. The particle is trapped in the transverse direction near the surface of the slab and can be pushed or pulled in the longitudinal direction along the surface of the slab. The pushing and pulling forces switch near the switching frequency of the slab. The manipulation of a small particle on the surface of a material due to the control of standing waves generated on the surface is presented. Evanescent waves pull the particle toward the surface of the material and the particle is trapped by the standing waves. Two mirrors are used and the adjustments of the mirrors allows precise and arbitrary manipulation of the trapped particle on the surface of the material. The magnitude of the pulling force on the particle depends on the angle of incident of light waves.

  20. Saving Space and Time: The Tractor That Einstein Built

    NASA Technical Reports Server (NTRS)

    2006-01-01

    In 1984, NASA initiated the Gravity Probe B (GP-B) program to test two unverified predictions of Albert Einstein s theory of general relativity, hypotheses about the ways space, time, light, and gravity relate to each other. To test these predictions, the Space Agency and researchers at Stanford University developed an experiment that would check, with extreme precision, tiny changes in the spin direction of four gyroscopes contained in an Earth satellite orbiting at a 400-mile altitude directly over the Earth s poles. When the program first began, the researchers assessed using Global Positioning System (GPS) technology to control the attitude of the GP-B spacecraft accurately. At that time, the best GPS receivers could only provide accuracy to nearly 1 meter, but the GP-B spacecraft required a system 100 times more accurate. To address this concern, researchers at Stanford designed high-performance, attitude-determining hardware that used GPS signals, perfecting a high-precision form of GPS called Carrier-Phase Differential GPS that could provide continuous real-time position, velocity, time, and attitude sensor information for all axes of a vehicle. The researchers came to the realization that controlling the GP-B spacecraft with this new system was essentially no different than controlling an airplane. Their thinking took a new direction: If this technology proved successful, the airlines and the Federal Aviation Administration (FAA) were ready commercial markets. They set out to test the new technology, the "Integrity Beacon Landing System," using it to automatically land a commercial Boeing 737 over 100 times successfully through Real-Time Kinematic (RTK) GPS technology. The thinking of the researchers shifted again, from automatically landing aircraft, to automating precision farming and construction equipment.

  1. TRACTOR REPAIR. AGRICULTURAL MACHINERY--SERVICE OCCUPATIONS, MODULE NUMBER 16.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center for Vocational and Technical Education.

    THE PURPOSE OF THIS GUIDE IS TO HELP TEACHERS PREPARE POSTSECONDARY STUDENTS FOR THE AGRICULTURAL MACHINERY SERVICE OCCUPATIONS AS PARTS MEN, MECHANICS, MECHANIC'S HELPERS, AND SERVICE SUPERVISORS. IT WAS DESIGNED BY A NATIONAL TASK FORCE ON THE BASIS OF RESEARCH FROM STATE STUDIES. THE MAJOR OBJECTIVE IS TO DEVELOP (1) AN UNDERSTANDING OF THE…

  2. CRAWLER HIDDEN UNDER MOBILE LAUNCHER MOVES APOLLO 17 FROM VEHICLE ASSEMBLY BUILDING AS TRIP TO LAUNC

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The Apollo 17 space vehicle was moved today from the Vehicle Assembly Building to Complex 39's pad A in preparation for its launch with Astronauts Eugene A. Cernan, Commander; Ronald A. Evans, Command Module Pilot; and Dr. Harrison H. ''Jack'' Schmitt, Lunar Module Pilot, on the sixth U.S. manned lunar landing mission on December 6, 1972.

  3. Connecting the Science User With Science Data and Services via the BCube Broker and Crawler

    NASA Astrophysics Data System (ADS)

    Khalsa, S. J. S.

    2015-12-01

    BCube, an NSF EarthCube Building Block project, aims to improve efficiency and productivity of geoscientists who work across disciplinary boundaries by facilitating discovery and access of geoscience data, linking major data facilities, and creating a new paradigm for data advertising and discovery. In this presentation we describe the achievements to date of the BCube brokering and web crawling efforts, addressing focus areas and outcomes in both cyberinfrastructure and geocsciences. We describe science scenarios illustrating the research in the ocean, climate, hydrology and polar domains that is being supported by the BCube Broker. By providing mediation between a diversity of standards and protocols the broker makes it possible for the geoscientists working in these demains to discover and access high-value datasets via a cloud-based interface. An Accessor Development Kit (ADK) enables the community to develop modules that extend the capabilities of the broker. In addition, we describe the web crawling and semantic technologies that are being applied to find new geoscience-relevant datasets and services on the web.

  4. Spiders and Worms and Crawlers, Oh My: Searching on the World Wide Web.

    ERIC Educational Resources Information Center

    Eagan, Ann; Bender, Laura

    Searching on the world wide web can be confusing. A myriad of search engines exist, often with little or no documentation, and many of these search engines work differently from the standard search engines people are accustomed to using. Intended for librarians, this paper defines search engines, directories, spiders, and robots, and covers basics…

  5. 78 FR 33860 - Crawler, Locomotive, and Truck Cranes Standard; Extension of the Office of Management and Budget...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-05

    ... reducing their risk of death or serious injury caused by a crane or rope failure during material handling... observe any deterioration resulting in appreciable loss of original strength and determine whether or not... Office (see the section of this notice titled ADDRESSES). The additional materials must clearly...

  6. 49 CFR 399.207 - Truck and truck-tractor access requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... is the final step in the sequence during exit, and the step is 508 millimeters (20 inches) or more... vertical height of the first step shall be no more than 609 millimeters (24 inches) from ground level. (3... a minimum 127 millimeter (5 inch) diameter disc as shown in Illustration III. (i) Single...

  7. 49 CFR 399.207 - Truck and truck-tractor access requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... is the final step in the sequence during exit, and the step is 508 millimeters (20 inches) or more... vertical height of the first step shall be no more than 609 millimeters (24 inches) from ground level. (3... a minimum 127 millimeter (5 inch) diameter disc as shown in Illustration III. (i) Single...

  8. Schedule-induced hours-of-service and speed limit violations among tractor-trailer drivers.

    PubMed

    Beilock, R

    1995-02-01

    Driver fatigue is well recognized as an important causational factor in accidents involving long-distance truck drivers. Drivers may drive while fatigued for a variety of reasons. Important among these is the assignment of difficult or unreasonable delivery schedules. Using self-reported data, the frequency of violation-inducing schedules is estimated during their ongoing movement for a sample of 498 long-distance drivers. Assuming average legal speed limits of 55 MPH, 26% of the drivers were found to have violation-inducing schedules. Solo drivers, drivers hauling refrigerated loads, regular route drivers, and those with longer current trip distances are the most likely to have such schedules. Also estimated were total weekly work hours. Assuming average attained travelling speeds of 50 MPH, the average driver drives 46 hours per week and works a total of 58 hours.

  9. 75 FR 82219 - Airworthiness Directives; Air Tractor, Inc. Models AT-802 and AT-802A Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-30

    .......... September 9, 2010 (75 FR Letter 284. 52255, August 25, 2010). (iii) Snow Engineering Co. Service Not...) Snow Engineering Co. Service Not Applicable........ April 25, 2005........ September 9, 2010 (75 FR..., 2004.... April 21, 2006 (71 FR Letter 240. 19994, April 19, 2006). (vi) Snow Engineering Co....

  10. TRACTOR TUNE-UP AND MAINTENANCE. AGRICULTURAL MACHINERY--SERVICE OCCUPATIONS, MODULE NUMBER 13.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center for Vocational and Technical Education.

    ONE OF A SERIES DESIGNED TO HELP TEACHERS PREPARE POSTSECONDARY STUDENTS FOR THE AGRICULTURAL MACHINERY SERVICE OCCUPATIONS AS PARTS MEN, MECHANICS, MECHANIC'S HELPERS, AND SERVICE SUPERVISORS, THIS GUIDE AIMS TO DEVELOP STUDENT UNDERSTANDING OF A SYSTEMATIC PROCEDURE AND ABILITY TO PERFORM TUNEUPS AND MAINTENANCE TASKS. IT WAS DEVELOPED BY A…

  11. Three-dimensional analysis of optical forces generated by an active tractor beam using radial polarization.

    PubMed

    Carretero, Luis; Acebal, Pablo; Blaya, Salvador

    2014-02-10

    We theoretically study the three-dimensional behavior of nanoparticles in an active optical conveyor. To do this, we solved the Langevin equation when the forces are generated by a focusing system at the near field. Analytical expressions for the optical forces generated by the optical conveyor were obtained by solving the Richards and Wolf vectorial diffraction integrals in an approximated form when a mask of two annular pupils is illuminated by a radially polarized Hermite-Gauss beam. Trajectories, in both the transverse plane and the longitudinal direction, are analyzed showing that the behavior of the optical conveyor can be optimized by conveniently choosing the configuration of the mask of the two annular pupils (inner and outer radius of the two rings) in order to trap and transport all particles at the focal plane. PMID:24663619

  12. Nonlinear analysis of a closed-loop tractor-semitrailer vehicle system with time delay

    NASA Astrophysics Data System (ADS)

    Liu, Zhaoheng; Hu, Kun; Chung, Kwok-wai

    2016-08-01

    In this paper, a nonlinear analysis is performed on a closed-loop system of articulated heavy vehicles with driver steering control. The nonlinearity arises from the nonlinear cubic tire force model. An integration method is employed to derive an analytical periodic solution of the system in the neighbourhood of the critical speed. The results show that excellent accuracy can be achieved for the calculation of periodic solutions arising from Hopf bifurcation of the vehicle motion. A criterion is obtained for detecting the Bautin bifurcation which separates branches of supercritical and subcritical Hopf bifurcations. The integration method is compared to the incremental harmonic balance method in both supercritical and subcritical scenarios.

  13. Tractor-mounted, GPS-based spot fumigation system manages Prunus replant disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our research goal was to use recent advances in global positioning system (GPS) and computer technology to apply just the right amount of fumigant where it is most needed (i.e., in a small target treatment zone in and around each tree replanting site) to control Prunus replant disease (PRD). We deve...

  14. 75 FR 52255 - Airworthiness Directives; Air Tractor, Inc. Models AT-802 and AT-802A Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-25

    ... FR 19994, April 19, 2006), the Director of the Federal Register approved the incorporation by..., AT-600, and AT- 800 series airplanes. In 2001, we issued AD 2001-10-04, Amendment 39-12230 (66 FR... full-time firefighting. In 2002, we issued AD 2002-11-05, Amendment 39-12766 (67 FR 37967, May 31,...

  15. 75 FR 35616 - Airworthiness Directives; Air Tractor, Inc. Models AT-802 and AT-802A Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-23

    ... airplane. DATES: This AD becomes effective on July 28, 2010. As of April 21, 2006 (71 FR 19994, April 19... (74 FR 39243). The NPRM proposed to supersede AD 2006-08-09 to clarify the SNs of the Models AT-802... Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and 3. Will not have a...

  16. Reducing Fuel Consumption through Semi-Automated Platooning with Class 8 Tractor Trailer Combinations (Poster)

    SciTech Connect

    Lammert, M.; Gonder, J.

    2014-07-01

    This poster describes the National Renewable Energy Laboratory's evaluation of the fuel savings potential of semi-automated truck platooning. Platooning involves reducing aerodynamic drag by grouping vehicles together and decreasing the distance between them through the use of electronic coupling, which allows multiple vehicles to accelerate or brake simultaneously. The NREL study addressed the need for data on American style line-haul sleeper cabs with modern aerodynamics and over a range of trucking speeds common in the United States.

  17. 76 FR 9495 - Airworthiness Directives; Air Tractor, Inc. Models AT-802 and AT-802A Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-18

    ... (using the eddy current method) the two outboard fastener holes in both of the wing main spar lower caps... life for certain serial number (SN) ranges. Our initial analysis indicated that a FRFA was necessary... condition. This action presents the FRFA for AD 2010-17-18, which is required to be published in the...

  18. Conserved and narrow temperature limits in alpine insects: Thermal tolerance and supercooling points of the ice-crawlers, Grylloblatta (Insecta: Grylloblattodea: Grylloblattidae).

    PubMed

    Schoville, Sean D; Slatyer, Rachel A; Bergdahl, James C; Valdez, Glenda A

    2015-07-01

    For many terrestrial species, habitat associations and range size are dependent on physiological limits, which in turn may influence large-scale patterns of species diversity. The temperature range experienced by individuals is considered to shape the breadth of the thermal niche, with species occupying temporally and/or geographically stable climates tolerating a narrow temperature range. High-elevation environments experience large temperature fluctuations, with frequent periods below 0 °C, but Grylloblatta (Grylloblattodea: Grylloblattidae) occupy climatically stable microhabitats within this region. Here we test critical thermal limits and supercooling points for five Grylloblatta populations from across a large geographic area, to examine whether the stable microhabitats of this group are associated with a narrow thermal niche and assess their capacity to tolerate cold conditions. Thermal limits are highly conserved in Grylloblatta, despite substantial genetic divergence among populations spanning 1500 m elevation and being separated by over 500 km. Further, Grylloblatta show exceptionally narrow thermal limits compared to other insect taxa with little capacity to improve cold tolerance via plasticity. In contrast, upper thermal limits were significantly depressed by cold acclimation. Grylloblatta maintain coordinated movement until they freeze, and they die upon freezing. Convergence of the critical thermal minima, supercooling point and lower lethal limits point to adaptation to a cold but, importantly, constant thermal environment. These physiological data provide an explanation for the high endemism and patchy distribution of Grylloblatta, which relies on subterranean retreats to accommodate narrow thermal limits. These retreats are currently buffered from temperature fluctuations by snow cover, and a declining snowpack thus places Grylloblatta at risk of exposure to temperatures beyond its tolerance capacity.

  19. DETAIL VIEW OF CONNECTOR FOR MATING THE MLP TO THE ...

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

    DETAIL VIEW OF CONNECTOR FOR MATING THE MLP TO THE CRAWLER. - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  20. Device for inspecting vessel surfaces

    DOEpatents

    Appel, D. Keith

    1995-01-01

    A portable, remotely-controlled inspection crawler for use along the walls of tanks, vessels, piping and the like. The crawler can be configured to use a vacuum chamber for supporting itself on the inspected surface by suction or a plurality of magnetic wheels for moving the crawler along the inspected surface. The crawler is adapted to be equipped with an ultrasonic probe for mapping the structural integrity or other characteristics of the surface being inspected. Navigation of the crawler is achieved by triangulation techniques between a signal transmitter on the crawler and a pair of microphones attached to a fixed, remote location, such as the crawler's deployment unit. The necessary communications are established between the crawler and computers external to the inspection environment for position control and storage and/or monitoring of data acquisition.

  1. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... The provisions of 29 CFR 1926.1001 for rubber-tired dozers and rubber-tired loaders may be used... used in construction work (see 29 CFR 1926.1002(b) and (j)). In the case of machines to which 29 CFR... protection provided in 29 CFR 1926.604, or the type of protection provided by this section. (b)...

  2. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... The provisions of 29 CFR 1926.1001 for rubber-tired dozers and rubber-tired loaders may be used... used in construction work (see 29 CFR 1926.1002(b) and (j)). In the case of machines to which 29 CFR... protection provided in 29 CFR 1926.604, or the type of protection provided by this section. (b)...

  3. Fuel-Cycle energy and emission impacts of ethanol-diesel blends in urban buses and farming tractors.

    SciTech Connect

    Wang, M.; Saricks, C.; Lee, H.

    2003-09-11

    About 2.1 billion gallons of fuel ethanol was used in the United States in 2002, mainly in the form of gasoline blends containing up to 10% ethanol (E10). Ethanol use has the potential to increase in the U.S. blended gasoline market because methyl tertiary butyl ether (MTBE), formerly the most popular oxygenate blendstock, may be phased out owing to concerns about MTBE contamination of the water supply. Ethanol would remain the only viable near-term option as an oxygenate in reformulated gasoline production and to meet a potential federal renewable fuels standard (RFS) for transportation fuels. Ethanol may also be blended with additives (co-solvents) into diesel fuels for applications in which oxygenation may improve diesel engine emission performance. Numerous studies have been conducted to evaluate the fuel-cycle energy and greenhouse gas (GHG) emission effects of ethanol-gasoline blends relative to those of gasoline for applications in spark-ignition engine vehicles (see Wang et al. 1997; Wang et al. 1999; Levelton Engineering et al. 1999; Shapouri et al. 2002; Graboski 2002). Those studies did not address the energy and emission effects of ethanol-diesel (E-diesel or ED) blends relative to those of petroleum diesel fuel in diesel engine vehicles. The energy and emission effects of E-diesel could be very different from those of ethanol-gasoline blends because (1) the energy use and emissions generated during diesel production (so-called ''upstream'' effects) are different from those generated during gasoline production; and (2) the energy and emission performance of E-diesel and petroleum diesel fuel in diesel compression-ignition engines differs from that of ethanol-gasoline blends in spark-ignition (Otto-cycle-type) engine vehicles. The Illinois Department of Commerce and Community Affairs (DCCA) commissioned Argonne National Laboratory to conduct a full fuel-cycle analysis of the energy and emission effects of E-diesel blends relative to those of petroleum diesel when used in the types of diesel engines that will likely be targeted first in the marketplace. This report documents the results of our study. The draft report was delivered to DCCA in January 2003. This final report incorporates revisions by the sponsor and by Argonne.

  4. Wind-Tunnel Tests of Four- and Six-Blade Single- and Dual-Rotating Tractor Propellers

    NASA Technical Reports Server (NTRS)

    Biermann, David; Hartman, Edwin P

    1942-01-01

    Test of 10-foot diameter, four and six blade single-rotating and dual-rotating propellers were conducted in the NACA propeller-research tunnel. The propellers were mounted at the front end of a streamline body incorporating spinners to house the hub portions. The effect of a symmetrical wing mounted in the slipstream ranged from 20 degrees to 65 degrees setting corresponds to airplane speeds greater than 500 miles per hour. The results indicate that dual-rotating propellers were from 0 to 6 percent more efficient than single-rotating ones; but, when the propellers operated in the presence of a wing, the gain was reduced by about one-half. Other advantages of dual-rotating propellers were found to include greater power absorption and greater efficiency at the low V/nD operating range of high-pitch propellers.

  5. Varnish forming properties of sunflower oil and how they relate to its use as fuel in diesel tractors

    SciTech Connect

    Olson, C.

    1982-05-01

    In diesel engines, polymerization of unburned sunflower oil forms a solid insoluble film or varnish on injectors, piston ring grooves and in lubricating oil. The chemical properties of sunflower oil which give rise to this effect are discussed. Partial hydrogenation of sunflower oil would seem to be the best solution for North Dakota sunflower oil at present. (Refs. 9).

  6. Potential of the tractor-trailer and container segments as entry markets for a proposed refrigeration technology

    SciTech Connect

    Smith, S.A.; Davis, L.J.; Garrett, B.A.

    1987-05-01

    The refrigerated trailer and container segments of the transportation industry are evaluated as potential entry markets for a proposed absorption refrigeration technology. To perform this analysis the existing transportation refrigeration industry is characterized; this includes a description of the current refrigeration technology, rating systems, equipment manufacturers, maintenance requirements, and sales trends. This information indicates that the current transportation refrigeration industry is composed of two major competitors, Thermo King and Carrier. In addition, it has low profit potential, some barriers to entry and low growth potential. Data are also presented that characterize the transportation refrigeration consumers, specifically, major groups, market segmentation, consumer decision process, and buying criteria. This consumer information indicates that the majority of refrigerated trailer consumers are private carriers, and that the majority of refrigerated container consumers are shipping companies. Also, these consumers are primarily interested in buying reliable equipment at a low price, and are quite satisfied with existing refrigeration equipment.

  7. Wind-tunnel Tests of Eight-blade Single and Dual-rotating Propellers in the Tractor Position

    NASA Technical Reports Server (NTRS)

    Gray, W.H.; Biermann, David

    1941-01-01

    Tests of 10-ft. diameter, eight-blade, single - and dual - rotating propellers were conducted in 20-ft propeller research tunnel. Propellers were mounted at front end of a streamline body in spinners that covered hubs and parts of shanks. Effect of a symmetrical wing mounted in slipstream was investigated. Blade-angle settings ranged from 20 Degrees to 65 Degrees. Results indicated that dual rotation resulted in gains of from 1 to 8 percent in efficiency over single rotation for eight-blade propellers, but presence of a wing reduced gain about one-half. Greater power absorption caused by dual rotation over flight range and higher efficiency or thrust for range of take-off and climb was indicated

  8. Farm Tractors, Occupational Therapy, and Four-Wheel Drive: Transforming a Military Vehicle into a Cultural Icon

    ERIC Educational Resources Information Center

    Iarocci, Andrew

    2010-01-01

    The armed forces of World War II employed unprecedented numbers of mechanical transport vehicles, precipitating a spike in demand for automotive manufactures. Eager to capture a share of the less certain postwar automobile marketplace, defense contractors such as Willys-Overland pursued a diverse range of product development and advertising…

  9. 29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... procedures and performance requirements. 1928.52 Section 1928.52 Labor Regulations Relating to Labor... for wheel-type agricultural tractors—test procedures and performance requirements. (a) Purpose. The purpose of this section is to establish the test and performance requirements for a protective...

  10. 29 CFR 1928.53 - Protective enclosures for wheel-type agricultural tractors-test procedures and performance...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and point of load application for both side and rear shall be the same as specified in 29 CFR 1928.52...-test procedures and performance requirements. 1928.53 Section 1928.53 Labor Regulations Relating to... enclosures for wheel-type agricultural tractors—test procedures and performance requirements. (a)...

  11. 29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... procedures and performance requirements. 1928.52 Section 1928.52 Labor Regulations Relating to Labor... for wheel-type agricultural tractors—test procedures and performance requirements. (a) Purpose. The purpose of this section is to establish the test and performance requirements for a protective...

  12. 29 CFR 1928.53 - Protective enclosures for wheel-type agricultural tractors-test procedures and performance...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and point of load application for both side and rear shall be the same as specified in 29 CFR 1928.52...-test procedures and performance requirements. 1928.53 Section 1928.53 Labor Regulations Relating to... enclosures for wheel-type agricultural tractors—test procedures and performance requirements. (a)...

  13. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... The provisions of 29 CFR 1926.1001 for rubber-tired dozers and rubber-tired loaders may be used... used in construction work (see 29 CFR 1926.1002(b) and (j)). In the case of machines to which 29 CFR... protection provided in 29 CFR 1926.604, or the type of protection provided by this section. (b)...

  14. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... The provisions of 29 CFR 1926.1001 for rubber-tired dozers and rubber-tired loaders may be used... used in construction work (see 29 CFR 1926.1002(b) and (j)). In the case of machines to which 29 CFR... protection provided in 29 CFR 1926.604, or the type of protection provided by this section. (b)...

  15. The Tractor and the Taxi: Rural and Urban Students Build a New Vehicle for Friendship in an Internet Mural Project.

    ERIC Educational Resources Information Center

    Stein, Sandra

    2001-01-01

    Describes how students in a rural Missouri high school collaborated online with students in an urban New York high school to create a mural in real space that celebrates the strengths of their two communities. Students had to conduct research, create a design, and then paint collaboratively via the Internet. The project forced them to address…

  16. New approaches to subglacial bedrock drilling technology

    NASA Astrophysics Data System (ADS)

    Talalay, Pavel; Sun, Youhong; Zhao, Yue; Xue, Jun; Chen, Chen; Markov, Alexey; Xu, Huiwen; Gong, Wenbin; Han, Wei; Zheng, Zhichuan; Cao, Pinlu; Wang, Rusheng; Zhang, Nan; Yu, Dahui; Fan, Xiaopeng; Hu, Zhengyi; Yang, Cheng; Han, Lili; Sysoev, Mikhail

    2013-04-01

    Drilling to bedrock of ice sheets and glaciers offers unique opportunities to research processes acting at the bed for paleo-climatic and paleo-environmental recording, basal sliding studies, subglacial geology and tectonics investigations, prospecting and exploration for minerals covered by ice. Retrieving bedrock samples under ice sheets and glaciers is a very difficult task. Drilling operations are complicated by extremely low temperature at the surface of, and within glaciers, and by glacier flow, the absence of roads and infrastructures, storms, winds, snowfalls, etc. In order to penetrate through the ice sheet or glacier up to the depth of at least 1000 m and to pierce the bedrock to the depth of several meters from ice - bedrock boundary the development activity already has been started in Polar Research Center at Jilin University, China. All drilling equipment (two 50-kW diesel generators, winch, control desk, fluid dumping station, etc.) is installed inside a movable sledge-mounted warm-keeping and wind-protecting drilling shelter that has dimensions of 8.8 ×2.8 × 3.0 m. Mast has two positions: horizontal for transportation and vertical working position (mast height is 12 m). Drilling shelter can be transported to the chosen site with crawler-tractor, aircraft or helicopter. In case of carriage by air the whole drilling shelter was designed to be disassembled into pieces "small" enough to ship by aircraft. Weight and sizes of each component has been minimized to lower the cost of transportation and to meet weight restrictions for transportation. Total weight of drilling equipment (without drilling fluid) is near 15 tons. Expected time of assembling and preparing for drilling is 2 weeks. If drilling shelter is transported with crawler-tractor (for example, in Antarctic traverses) all equipment is ready to start drilling immediately upon arrival to the site. To drill through ice and bedrock a new, modified version of the cable-suspended electromechanical

  17. Quick-Fit Trailer Coupling For A Grader

    NASA Technical Reports Server (NTRS)

    Soper, Terry A.; Moulton, Calvin T.

    1992-01-01

    Ripper attachment on grading tractor adapted to lift tongue of trailer tow bar hydraulically. Unnecessary for tractor operator to use jack or fork, lift to raise tongue. Enables tractor operator, acting alone, to hitch trailer to tractor, without expense and complication of dedicated hydraulic lifting mechanism for trailer hitch.

  18. KSC-04PD-1041

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-114 Mission Specialist Andrew Thomas stands next to the 10-foot-high track on a Crawler- Transporter. He and Pilot James Kelly toured the crawler storage area during a visit to KSC. The crawlers had recent modifications to the cab and muffler system. The STS-114 mission is Logistics Flight 1, which is scheduled to deliver supplies and equipment plus the external stowage platform to the International Space Station.

  19. KSC-04PD-1040

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-114 Pilot James Kelly (left) and Mission Specialist Andrew Thomas (center), along with NASA Systems Engineer Robert Rokobauer (right), look closely at the shoes of one of the tracks used on a Crawler-Transporter. The 10- foot-high track on a crawler contains 278 shoes, weighing 2,200 pounds each. The crawlers are guided by four trucks, one on each corner. The crawlers had recent modifications to the cab and muffler system. The STS-114 mission is Logistics Flight 1, which is scheduled to deliver supplies and equipment plus the external stowage platform to the International Space Station.

  20. Carpenter, Tractors and Microbes for the Development of Logical-Mathematical Thinking--The Way 10th Graders and Pre-Service Teachers Solve Thinking Challenges

    ERIC Educational Resources Information Center

    Gazit, Avikam

    2012-01-01

    The objective of this case study was to investigate the ability of 10th graders and pre-service teachers to solve logical-mathematical thinking challenges. The challenges do not require mathematical knowledge beyond that of primary school but rather an informed use of the problem representation. The percentage of correct answers given by the 10th…

  1. Tests of Nacelle-propeller Combinations in Various Positions with Reference to Wings. Part I : Thick Wing-N.A.C.A. Cowled Nacelle-Tractor Propeller

    NASA Technical Reports Server (NTRS)

    Wood, Donald H

    1933-01-01

    This report gives the results in the 20-foot propeller research tunnel of the National Advisory Committee for Aeronautics on the interference drag and propulsive efficiency of a nacelle-propeller combination located in 21 positions with reference to a thick wing. The lift, drag, and propulsive efficiency were obtained at several angles of attack for each of the 21 locations. A net efficiency was derived for determining the over-all effectiveness of each nacelle location. Best results were obtained with the propeller about 25 per cent of the chord directly ahead of the leading edge. A location immediately above or below the wing near the leading edge was very poor.

  2. Carpenter, tractors and microbes for the development of logical-mathematical thinking - the way 10th graders and pre-service teachers solve thinking challenges

    NASA Astrophysics Data System (ADS)

    Gazit, Avikam

    2012-12-01

    The objective of this case study was to investigate the ability of 10th graders and pre-service teachers to solve logical-mathematical thinking challenges. The challenges do not require mathematical knowledge beyond that of primary school but rather an informed use of the problem representation. The percentage of correct answers given by the 10th graders was higher than that of the pre-service teachers. Unlike the 10th graders, some of whom used various strategies for representing the problem, most of the pre-service teachers' answers were based on a technical algorithm, without using control processes. The obvious conclusion drawn from the findings supports and recommends expanding and enhancing the development of logical-mathematical thinking, both in specific lessons and as an integral part of other lessons in pre-service frameworks.

  3. Assessment of solar photocatalysis to purify on-site rinse waters from tractor cisterns used in grapevine pest control: field experimentation.

    PubMed

    Pichat, P; Vannier, S; Dussaud, J; Rubis, J P

    2005-01-01

    The aim of this study was to assess in a vineyard the effect of purifying by solar photocatalysis the title rinse waters (currently most often rejected) in terms of efficacy and on-site practicality for the wine grower. The on-site, self-functioning, solar purifying unit included a corrugated-steel inclined plate of area S = 1 m2 onto which a TiO2-coated thin material had been slightly pressed, a tank, and an aquarium-type pump powered by a photovoltaic panel (appropriate for isolated locations). For a vineyard of area A = 0.15 km2, the rinse water (about 90 L) corresponding to each of four typical vine treatments in summer was analysed (major pesticides for each treatment, TOC, Microtox test and, in one case, BOD5) by independent laboratories, before and after purification for 8 days. The S/A ratio tested was found insufficient even if the photocatalytic treatment markedly improved the quality of the rinse waters. From the relatively low final organic content reached in one case, it is calculated that a three-time higher S/A ratio might suffice, but new trials are necessary to determine whether it is valid for other typical cases. Inferred contribution of inorganic ions to the post-photocatalytic treatment toxicity points to the need for an additional detoxification. These field experiments have also demonstrated that the purifying prototype is robust, and easy to install and use on site by the wine grower. PMID:16312971

  4. Assessment of solar photocatalysis to purify on-site rinse waters from tractor cisterns used in grapevine pest control: field experimentation.

    PubMed

    Pichat, P; Vannier, S; Dussaud, J; Rubis, J P

    2005-01-01

    The aim of this study was to assess in a vineyard the effect of purifying by solar photocatalysis the title rinse waters (currently most often rejected) in terms of efficacy and on-site practicality for the wine grower. The on-site, self-functioning, solar purifying unit included a corrugated-steel inclined plate of area S = 1 m2 onto which a TiO2-coated thin material had been slightly pressed, a tank, and an aquarium-type pump powered by a photovoltaic panel (appropriate for isolated locations). For a vineyard of area A = 0.15 km2, the rinse water (about 90 L) corresponding to each of four typical vine treatments in summer was analysed (major pesticides for each treatment, TOC, Microtox test and, in one case, BOD5) by independent laboratories, before and after purification for 8 days. The S/A ratio tested was found insufficient even if the photocatalytic treatment markedly improved the quality of the rinse waters. From the relatively low final organic content reached in one case, it is calculated that a three-time higher S/A ratio might suffice, but new trials are necessary to determine whether it is valid for other typical cases. Inferred contribution of inorganic ions to the post-photocatalytic treatment toxicity points to the need for an additional detoxification. These field experiments have also demonstrated that the purifying prototype is robust, and easy to install and use on site by the wine grower.

  5. Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings II : Thick Wing - Various Radial-Engine Cowlings - Tractor Propeller

    NASA Technical Reports Server (NTRS)

    Wood, Donald H

    1932-01-01

    This report is the second of a series giving the results obtained in the 20-foot wind tunnel of the National Advisory Committee for Aeronautics on the interference drag and propulsive efficiency of nacelle-propeller-wing combinations. The first report gave the results of the test of a N.A.C.A. cowled air-cooled engine nacelle located in 21 positions with reference to a thick wing. The present report gives results of tests of a normal engine nacelle with several types of cowling and fairings in four of the positions with reference to the same wing. (author)

  6. Ground Systems Development and Operations: Exploration Begins Here

    NASA Technical Reports Server (NTRS)

    Hanna, Mary; Phillips, Pepper; VanNes, Timothy

    2012-01-01

    Hunger Hydraulik of Lohr, Germany has been selected as the vendor to build replacement Jacking, Leveling and Equalization cylinders for one Crawler Transporter. A site visit has been scheduled and a overview of how the Crawler Transporter fits into KSC launch operations will be presented as information. The presentation will be presented on July 11, 2012 by Pepper Phillips, the Program Manager for GSDO.

  7. 77 FR 71850 - Self-Regulatory Organizations; International Securities Exchange, LLC; Notice of Filing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-04

    ...-time. From the matching list of registered end- users, Spread Crawler then creates and transmits... line technical support, accounting and contract administration services for Spread Crawler. In exchange... equitable principles of trade, to foster cooperation and coordination with persons engaged in...

  8. KSC-04PD-1042

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-114 Mission Specialist Andrew Thomas takes a look inside one of the cabs on a Crawler- Transporter. The crawlers had recent modifications to the cab and muffler system. The STS-114 mission is Logistics Flight 1, which is scheduled to deliver supplies and equipment plus the external stowage platform to the International Space Station.

  9. KSC-04PD-1043

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-114 Pilot James Kelly (left) talks with NASA Systems Engineer Robert Rokobauer inside one of the cabs on a Crawler-Transporter. The crawlers had recent modifications to the cab and muffler system. The STS-114 mission is Logistics Flight 1, which is scheduled to deliver supplies and equipment plus the external stowage platform to the International Space Station.

  10. 29 CFR 1915.115 - Hoisting and hauling equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... equipment shall be guarded. (c) Mobile crawler or truck cranes used on a vessel. (1) The maximum... posted safe working loads of mobile crawler or truck cranes under the conditions of use shall not be... this section shall apply to ship repairing, shipbuilding and shipbreaking. (a) Derrick and...

  11. 29 CFR 1915.115 - Hoisting and hauling equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... equipment shall be guarded. (c) Mobile crawler or truck cranes used on a vessel. (1) The maximum... posted safe working loads of mobile crawler or truck cranes under the conditions of use shall not be... this section shall apply to ship repairing, shipbuilding and shipbreaking. (a) Derrick and...

  12. 29 CFR 1915.115 - Hoisting and hauling equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... equipment shall be guarded. (c) Mobile crawler or truck cranes used on a vessel. (1) The maximum... posted safe working loads of mobile crawler or truck cranes under the conditions of use shall not be... this section shall apply to ship repairing, shipbuilding and shipbreaking. (a) Derrick and...

  13. 29 CFR 1915.115 - Hoisting and hauling equipment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... equipment shall be guarded. (c) Mobile crawler or truck cranes used on a vessel. (1) The maximum... posted safe working loads of mobile crawler or truck cranes under the conditions of use shall not be... this section shall apply to ship repairing, shipbuilding and shipbreaking. (a) Derrick and...

  14. 49 CFR 383.95 - Restrictions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... transmission as defined in § 383.5. (d) Tractor-trailer. If an applicant performs the skills test in a... restricted from operating a tractor-trailer combination connected by a fifth wheel that requires a Group...

  15. 49 CFR 383.95 - Restrictions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... transmission as defined in § 383.5. (d) Tractor-trailer. If an applicant performs the skills test in a... restricted from operating a tractor-trailer combination connected by a fifth wheel that requires a Group...

  16. 78 FR 11266 - Agency Information Collection Activities: Request for Comments for a New Information Collection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-15

    ... inspection. In August of 2008, tractor-trailer dislodged a section of barrier on the William Preston Lane, Jr. Memorial Bridge. Portions of the displaced barrier separated and the tractor-trailer fatally departed...

  17. 49 CFR 383.95 - Restrictions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... transmission as defined in § 383.5. (d) Tractor-trailer. If an applicant performs the skills test in a... restricted from operating a tractor-trailer combination connected by a fifth wheel that requires a Group...

  18. 41 CFR 101-26.501-1 - General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... truck tractors (FSC 2320), trailers (FSC 2330) van type (with payload of not less than 5,000 nor more..., commercial-type passenger motor vehicles (FSC 2310), including buses, and trucks and truck tractors (FSC...

  19. 78 FR 44567 - Proposed Data Collections Submitted for Public Comment and Recommendations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ... injury among farm workers, NIOSH proposes to administer stated-preference questionnaires designed to... hrs) Tractor Parts Dealers......... ROPS 468 1 5/60 39 Questionnaire for Tractor Parts Dealers....

  20. 75 FR 68663 - Federal Motor Vehicle Safety Standards; Rear Impact Guards; Rear Impact Protection; Technical...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-08

    ... passenger vehicle impacts the rear of a ] tractor-trailer. The primary findings are the following: Data from... occupants when rear-ending a tractor-trailer subsequent to the implementation of Safety Standards 223 and... passenger vehicle rear-ends a tractor- trailer--neither in terms of total number of fatalities,...

  1. 77 FR 20879 - Qualification of Drivers; Exemption Applications; Vision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-06

    ... million miles and tractor-trailer combinations for 25 years, accumulating 2.3 million miles. He holds a...,000 miles and tractor- trailer combinations for 5 years, accumulating 1,250 miles. He holds a Class A..., accumulating 60,000 miles and tractor- trailer combinations for 3 years, accumulating 15,000 miles. He holds...

  2. 77 FR 33017 - Qualification of Drivers; Exemption Applications; Vision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-04

    ... years, accumulating 372,000 miles, and tractor-trailer combinations for 31 years, accumulating 372,000... driven straight trucks for 8 years, accumulating 220,000 miles, and tractor-trailer combinations for 2..., accumulating 320,000 miles, and tractor-trailer combinations for 10 years, accumulating 320,000 miles. He...

  3. 78 FR 12815 - Qualification of Drivers; Exemption Applications; Vision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-25

    ... has driven straight trucks for 35 years, accumulating 350,000 miles, and tractor-trailer combinations... contraindications for commercial driving.'' Mr. Clark reported that he has driven tractor-trailer combinations for... years, accumulating 517,500 miles, and tractor-trailer combinations for 27 years, accumulating...

  4. 78 FR 16912 - Qualification of Drivers; Exemption Applications; Vision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-19

    ..., accumulating 540,000 miles, and tractor-trailer combinations for 15 years, accumulating 375,000 miles. He holds... driven straight trucks for 12 years, accumulating 1 million miles, and tractor-trailer combinations for 4... tractor-trailer combinations for 25, accumulating 2.5 million miles. He holds a Class A CDL from...

  5. Energy and Agriculture. A Basic Core Curriculum for Teaching Energy to Vocational Agriculture Students.

    ERIC Educational Resources Information Center

    Albracht, James; French, Byron

    This core curriculum contains five units of material for teaching energy to vocational agriculture students. Energy uses and the benefits of energy conservation are covered in a unit on the impact of energy on agriculture. Discussed next are tractor performance and Nebraska tractor test data for selecting and evaluating tractors for maximum fuel…

  6. 26 CFR 1.471-4 - Inventories at cost or market, whichever is lower.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... materials, direct labor, and indirect costs required to be included in inventories by the taxpayer (e.g... following examples: Example 1. (i) Taxpayer A manufactures tractors. A values its inventory using cost or... market value of the tractor, A compares the cost of the tractor, $10,000, with the market value of...

  7. 29 CFR 1926.1423 - Fall protection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... crawler treads, must have slip-resistant features/properties (such as diamond plate metal, strategically... must have slip-resistant features/properties (such as diamond plate metal, strategically placed...

  8. 29 CFR 1926.1423 - Fall protection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... crawler treads, must have slip-resistant features/properties (such as diamond plate metal, strategically... must have slip-resistant features/properties (such as diamond plate metal, strategically placed...

  9. 29 CFR 1926.1423 - Fall protection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... crawler treads, must have slip-resistant features/properties (such as diamond plate metal, strategically... must have slip-resistant features/properties (such as diamond plate metal, strategically placed...

  10. 29 CFR 1926.1423 - Fall protection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... crawler treads, must have slip-resistant features/properties (such as diamond plate metal, strategically... must have slip-resistant features/properties (such as diamond plate metal, strategically placed...

  11. KSC-03PD-3120

    NASA Technical Reports Server (NTRS)

    2003-01-01

    KENNEDY SPACE CENTER, FLA. The crawler transporter slowly moves the Mobile Launcher Platform (MLP), carrying a set of twin solid rocket boosters, away from the Vehicle Assembly Building (VAB) in support of engineering analysis vibration tests on the crawler and MLP. In the distance, at left, is Launch Pad 39A. The water on the right of the crawlerway is the Banana River. The crawler is moving at various speeds up to 1 mph in an effort to achieve vibration data gathering goals as it leaves the VAB and then returns. The boosters are braced at the top for stability. The primary purpose of these rollout tests is to gather data to develop future maintenance requirements on the transport equipment and the flight hardware. Various parts of the MLP and crawler transporter have been instrumented with vibration data collection equipment.

  12. KSC-03PD-3128

    NASA Technical Reports Server (NTRS)

    2003-01-01

    KENNEDY SPACE CENTER, FLA. Viewed across the turn basin in the Launch Complex 39 Area, the crawler transporter slowly moves the Mobile Launcher Platform (MLP), carrying a set of twin solid rocket boosters, away from the Vehicle Assembly Building (VAB). The journey is in support of engineering analysis vibration tests on the crawler and MLP. The water on the right of the crawlerway is the Banana River. The crawler is moving at various speeds up to 1 mph in an effort to achieve vibration data gathering goals as it leaves the VAB and then returns. The boosters are braced at the top for stability. The primary purpose of these rollout tests is to gather data to develop future maintenance requirements on the transport equipment and the flight hardware. Various parts of the MLP and crawler transporter have been instrumented with vibration data collection equipment.

  13. Slow-motion Giants

    NASA Video Gallery

    For more than 40 years, the twin crawler-transporters that first carried all the Apollo Saturn V rockets to the launch pad have borne every space shuttle on the last Earth-bound leg of their journe...

  14. VIEW OF THE JACKING, ELEVATING, AND LEVELING SKID. Cape ...

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

    VIEW OF THE JACKING, ELEVATING, AND LEVELING SKID. - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  15. Development of a High Level Waste Tank Inspection System

    SciTech Connect

    Appel, D.K.; Loibl, M.W.; Meese, D.C.

    1995-03-21

    The Westinghouse Savannah River Technology Center was requested by it`s sister site, West Valley Nuclear Service (WVNS), to develop a remote inspection system to gather wall thickness readings of their High Level Waste Tanks. WVNS management chose to take a proactive approach to gain current information on two tanks t hat had been in service since the early 70`s. The tanks contain high level waste, are buried underground, and have only two access ports to an annular space between the tank and the secondary concrete vault. A specialized remote system was proposed to provide both a visual surveillance and ultrasonic thickness measurements of the tank walls. A magnetic wheeled crawler was the basis for the remote delivery system integrated with an off-the-shelf Ultrasonic Data Acquisition System. A development program was initiated for Savannah River Technology Center (SRTC) to design, fabricate, and test a remote system based on the Crawler. The system was completed and involved three crawlers to perform the needed tasks, an Ultrasonic Crawler, a Camera Crawler, and a Surface Prep Crawler. The crawlers were computer controlled so that their operation could be done remotely and their position on the wall could be tracked. The Ultrasonic Crawler controls were interfaced with ABB Amdata`s I-PC, Ultrasonic Data Acquisition System so that thickness mapping of the wall could be obtained. A second system was requested by Westinghouse Savannah River Company (WSRC), to perform just ultrasonic mapping on their similar Waste Storage Tanks; however, the system needed to be interfaced with the P-scan Ultrasonic Data Acquisition System. Both remote inspection systems were completed 9/94. Qualifications tests were conducted by WVNS prior to implementation on the actual tank and tank development was achieved 10/94. The second inspection system was deployed at WSRC 11/94 with success, and the system is now in continuous service inspecting the remaining high level waste tanks at WSRC.

  16. Trailer-Tank-Truck Driver (petrol. refin; ret. tr.; whole. tr.) 903.883; Tractor-Trailer-Truck Driver (any ind.) 904.883--Technical Report on Development of USES Aptitude Test Battery.

    ERIC Educational Resources Information Center

    Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.

    The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…

  17. Design Improvements and Analysis of Innovative High-Level Waste Pipeline Unplugging Technologies - 12171

    SciTech Connect

    Pribanic, Tomas; Awwad, Amer; Crespo, Jairo; McDaniel, Dwayne; Varona, Jose; Gokaltun, Seckin; Roelant, David

    2012-07-01

    Transferring high-level waste (HLW) between storage tanks or to treatment facilities is a common practice performed at the Department of Energy (DoE) sites. Changes in the chemical and/or physical properties of the HLW slurry during the transfer process may lead to the formation of blockages inside the pipelines resulting in schedule delays and increased costs. To improve DoE's capabilities in the event of a pipeline plugging incident, FIU has continued to develop two novel unplugging technologies: an asynchronous pulsing system and a peristaltic crawler. The asynchronous pulsing system uses a hydraulic pulse generator to create pressure disturbances at two opposite inlet locations of the pipeline to dislodge blockages by attacking the plug from both sides remotely. The peristaltic crawler is a pneumatic/hydraulic operated crawler that propels itself by a sequence of pressurization/depressurization of cavities (inner tubes). The crawler includes a frontal attachment that has a hydraulically powered unplugging tool. In this paper, details of the asynchronous pulsing system's ability to unplug a pipeline on a small-scale test-bed and results from the experimental testing of the second generation peristaltic crawler are provided. The paper concludes with future improvements for the third generation crawler and a recommended path forward for the asynchronous pulsing testing. (authors)

  18. Shuttle crew escape systems (CES) rocket test at Hurricane Mesa, Utah

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Shuttle crew escape systems (CES) tractor rocket tests conducted at Hurricane Mesa, Utah. This preliminary ground test of the tractor rocket will lead up to in-air evaluations. View shows tractor rocket as it is fired from side hatch mockup. The tractor rocket concept is one of two escape methods being studied to provide crew egress capability during Space Shuttle controlled gliding flight. In-air tests of the system, utilizing a Convair-240 aircraft, will begin 11-19-87 at the Naval Weapons Center in China Lake, California.

  19. 30 CFR 46.8 - Annual refresher training.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... covered by this rule, including: mobile equipment (haulage and service trucks, front-end loaders and tractors); conveyor systems; cranes; crushers; excavators; and dredges. Other recommended subjects...

  20. 30 CFR 46.8 - Annual refresher training.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... covered by this rule, including: mobile equipment (haulage and service trucks, front-end loaders and tractors); conveyor systems; cranes; crushers; excavators; and dredges. Other recommended subjects...

  1. 30 CFR 46.8 - Annual refresher training.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... covered by this rule, including: mobile equipment (haulage and service trucks, front-end loaders and tractors); conveyor systems; cranes; crushers; excavators; and dredges. Other recommended subjects...

  2. 30 CFR 46.8 - Annual refresher training.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... covered by this rule, including: mobile equipment (haulage and service trucks, front-end loaders and tractors); conveyor systems; cranes; crushers; excavators; and dredges. Other recommended subjects...

  3. Design Optimization of Innovative High-Level Waste Pipeline Unplugging Technologies - 13341

    SciTech Connect

    Pribanic, T.; Awwad, A.; Varona, J.; McDaniel, D.; Gokaltun, S.; Crespo, J.

    2013-07-01

    Florida International University (FIU) is currently working on the development and optimization of two innovative pipeline unplugging methods: the asynchronous pulsing system (APS) and the peristaltic crawler system (PCS). Experiments were conducted on the APS to determine how air in the pipeline influences the system's performance as well as determine the effectiveness of air mitigation techniques in a pipeline. The results obtained during the experimental phase of the project, including data from pipeline pressure pulse tests along with air bubble compression tests are presented. Single-cycle pulse amplification caused by a fast-acting cylinder piston pump in 21.8, 30.5, and 43.6 m pipelines were evaluated. Experiments were conducted on fully flooded pipelines as well as pipelines that contained various amounts of air to evaluate the system's performance when air is present in the pipeline. Also presented are details of the improvements implemented to the third generation crawler system (PCS). The improvements include the redesign of the rims of the unit to accommodate a camera system that provides visual feedback of the conditions inside the pipeline. Visual feedback allows the crawler to be used as a pipeline unplugging and inspection tool. Tests conducted previously demonstrated a significant reduction of the crawler speed with increasing length of tether. Current improvements include the positioning of a pneumatic valve manifold system that is located in close proximity to the crawler, rendering tether length independent of crawler speed. Additional improvements to increase the crawler's speed were also investigated and presented. Descriptions of the test beds, which were designed to emulate possible scenarios present on the Department of Energy (DOE) pipelines, are presented. Finally, conclusions and recommendations for the systems are provided. (authors)

  4. Wi-Fi and Satellite-Based Location Techniques for Intelligent Agricultural Machinery Controlled by a Human Operator

    PubMed Central

    Drenjanac, Domagoj; Tomic, Slobodanka; Agüera, Juan; Perez-Ruiz, Manuel

    2014-01-01

    In the new agricultural scenarios, the interaction between autonomous tractors and a human operator is important when they jointly perform a task. Obtaining and exchanging accurate localization information between autonomous tractors and the human operator, working as a team, is a critical to maintaining safety, synchronization, and efficiency during the execution of a mission. An advanced localization system for both entities involved in the joint work, i.e., the autonomous tractors and the human operator, provides a basis for meeting the task requirements. In this paper, different localization techniques for a human operator and an autonomous tractor in a field environment were tested. First, we compared the localization performances of two global navigation satellite systems’ (GNSS) receivers carried by the human operator: (1) an internal GNSS receiver built into a handheld device; and (2) an external DGNSS receiver with centimeter-level accuracy. To investigate autonomous tractor localization, a real-time kinematic (RTK)-based localization system installed on autonomous tractor developed for agricultural applications was evaluated. Finally, a hybrid localization approach, which combines distance estimates obtained using a wireless scheme with the position of an autonomous tractor obtained using an RTK-GNSS system, is proposed. The hybrid solution is intended for user localization in unstructured environments in which the GNSS signal is obstructed. The hybrid localization approach has two components: (1) a localization algorithm based on the received signal strength indication (RSSI) from the wireless environment; and (2) the acquisition of the tractor RTK coordinates when the human operator is near the tractor. In five RSSI tests, the best result achieved was an average localization error of 4 m. In tests of real-time position correction between rows, RMS error of 2.4 cm demonstrated that the passes were straight, as was desired for the autonomous tractor

  5. Wi-Fi and satellite-based location techniques for intelligent agricultural machinery controlled by a human operator.

    PubMed

    Drenjanac, Domagoj; Tomic, Slobodanka; Agüera, Juan; Perez-Ruiz, Manuel

    2014-10-22

    In the new agricultural scenarios, the interaction between autonomous tractors and a human operator is important when they jointly perform a task. Obtaining and exchanging accurate localization information between autonomous tractors and the human operator, working as a team, is a critical to maintaining safety, synchronization, and efficiency during the execution of a mission. An advanced localization system for both entities involved in the joint work, i.e., the autonomous tractors and the human operator, provides a basis for meeting the task requirements. In this paper, different localization techniques for a human operator and an autonomous tractor in a field environment were tested. First, we compared the localization performances of two global navigation satellite systems' (GNSS) receivers carried by the human operator: (1) an internal GNSS receiver built into a handheld device; and (2) an external DGNSS receiver with centimeter-level accuracy. To investigate autonomous tractor localization, a real-time kinematic (RTK)-based localization system installed on autonomous tractor developed for agricultural applications was evaluated. Finally, a hybrid localization approach, which combines distance estimates obtained using a wireless scheme with the position of an autonomous tractor obtained using an RTK-GNSS system, is proposed. The hybrid solution is intended for user localization in unstructured environments in which the GNSS signal is obstructed. The hybrid localization approach has two components: (1) a localization algorithm based on the received signal strength indication (RSSI) from the wireless environment; and (2) the acquisition of the tractor RTK coordinates when the human operator is near the tractor. In five RSSI tests, the best result achieved was an average localization error of 4 m. In tests of real-time position correction between rows, RMS error of 2.4 cm demonstrated that the passes were straight, as was desired for the autonomous tractor. From

  6. Wi-Fi and satellite-based location techniques for intelligent agricultural machinery controlled by a human operator.

    PubMed

    Drenjanac, Domagoj; Tomic, Slobodanka; Agüera, Juan; Perez-Ruiz, Manuel

    2014-01-01

    In the new agricultural scenarios, the interaction between autonomous tractors and a human operator is important when they jointly perform a task. Obtaining and exchanging accurate localization information between autonomous tractors and the human operator, working as a team, is a critical to maintaining safety, synchronization, and efficiency during the execution of a mission. An advanced localization system for both entities involved in the joint work, i.e., the autonomous tractors and the human operator, provides a basis for meeting the task requirements. In this paper, different localization techniques for a human operator and an autonomous tractor in a field environment were tested. First, we compared the localization performances of two global navigation satellite systems' (GNSS) receivers carried by the human operator: (1) an internal GNSS receiver built into a handheld device; and (2) an external DGNSS receiver with centimeter-level accuracy. To investigate autonomous tractor localization, a real-time kinematic (RTK)-based localization system installed on autonomous tractor developed for agricultural applications was evaluated. Finally, a hybrid localization approach, which combines distance estimates obtained using a wireless scheme with the position of an autonomous tractor obtained using an RTK-GNSS system, is proposed. The hybrid solution is intended for user localization in unstructured environments in which the GNSS signal is obstructed. The hybrid localization approach has two components: (1) a localization algorithm based on the received signal strength indication (RSSI) from the wireless environment; and (2) the acquisition of the tractor RTK coordinates when the human operator is near the tractor. In five RSSI tests, the best result achieved was an average localization error of 4 m. In tests of real-time position correction between rows, RMS error of 2.4 cm demonstrated that the passes were straight, as was desired for the autonomous tractor. From

  7. Exploration of Gamburtsev Subglacial Mountains, East Antarctica: Background and Plans for the Near Future

    NASA Astrophysics Data System (ADS)

    Talalay, Pavel; Sun, Youhong; Zhao, Yue; Li, Yuansheng; Cao, Pinlu; Xu, Huiwen; Zheng, Zhichuan; Wang, Rusheng; Zhang, Nan; Markov, Alexey; Yu, Dahui; Fan, Xiaopeng; Hu, Zhengyi; Yang, Cheng; Gong, Da; Hong, Jialing; Liu, Chunpeng; Han, Junjie; Yu, Chengfeng; Wang, Lili

    2014-05-01

    drilling of upper permeable snow-firn layer with bottom-air reverse circulation; (2) reaming; (3) casing installation; (4) fluid core drilling of glacial ice with bottom-fluid reverse circulation; (5) bedrock core drilling. All drilling equipment will be installed inside a movable sledge-mounted warm-keeping and wind-protecting drilling shelter that is transported to the chosen site with crawler-tractor. The new approaches of subglacial bedrock drilling technology are connected with utilization of environmental friendly, low-toxic drilling fluids, e.g. low-molecular dimethyl siloxane oils or ester type. They have suitable density-viscosity properties, and can be consider as a viable alternative for drilling in glacial ice and subglacial bedrock. According to approved schedule, the first field tests are planned to carry out just outside Zhongshan Station near Antarctic coast in season 2015-2016. Next season 2016-2017 the movable drilling shelter is planned to be transported to the chosen drilling site in the GSM region, and drilling to the bedrock would be finished during two seasons.

  8. 49 CFR 383.135 - Passing knowledge and skills tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Group A CDL equipped with any non-fifth wheel connection is issued a CDL, a tractor-trailer restriction... knowledge test. (8) If a driver applicant wants to remove the tractor-trailer restriction in paragraph (b)(6) of this section, the applicant must retake all three skills tests in a representative...

  9. 49 CFR 383.135 - Passing knowledge and skills tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Group A CDL equipped with any non-fifth wheel connection is issued a CDL, a tractor-trailer restriction... knowledge test. (8) If a driver applicant wants to remove the tractor-trailer restriction in paragraph (b)(6) of this section, the applicant must retake all three skills tests in a representative...

  10. 49 CFR 383.135 - Passing knowledge and skills tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Group A CDL equipped with any non-fifth wheel connection is issued a CDL, a tractor-trailer restriction... knowledge test. (8) If a driver applicant wants to remove the tractor-trailer restriction in paragraph (b)(6) of this section, the applicant must retake all three skills tests in a representative...

  11. 78 FR 26611 - Notice of Intent To Seek Approval To Conduct an Information Collection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-07

    ... and title above in the subject line of the message. Fax: (202)720-6396. Mail: Mail any paper, disk, or... other than helicopters, airplanes, or equipment pulled by enclosed cab tractors or ATVs. The primary..., airplanes, or equipment pulled by enclosed cab tractors or ATVs. Estimated Number of Respondents:...

  12. 23 CFR 658.13 - Length.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... safety regulations at 49 CFR parts 390-399. (2) Boat transporters. (i) Boat transporters are considered... meaning as in 49 CFR 393.5. (iii) Truck tractor-beverage semitrailer combinations shall have the same...) in 23 CFR 658.19. (6) Munitions carriers using dromedary equipment. A truck tractor equipped with...

  13. HEAVY-DUTY GREENHOUSE GAS EMISSIONS MODEL (GEM)

    EPA Science Inventory

    Class 2b-8 vocational truck manufacturers and Class 7/8 tractor manufacturers would be subject to vehicle-based fuel economy and emission standards that would use a truck simulation model to evaluate the impact of the truck tires and/or tractor cab design on vehicle compliance wi...

  14. 41 CFR 101-39.301 - Utilization guidelines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... lbs. GVWR—7,500 miles per year. (c) Heavy trucks and truck tractors. The utilization guidelines for heavy trucks and truck tractors are as follows: (1) Heavy trucks and general purpose vehicles over 24,000 lbs. GVWR—7,500 miles per year. (2) Truck tractors—10,000 miles per year. (d) Other trucks...

  15. Truck Safety. Information on Driver Training. Report to Congressional Requesters.

    ERIC Educational Resources Information Center

    General Accounting Office, Washington, DC. Resources, Community, and Economic Development Div.

    The General Accounting Office examined the types of training available for tractor-trailer drivers, focusing on the Federal Highway Administration's (FHWA's) efforts to establish minimum federal standards for training tractor-trailer drivers, the driver training curriculum offered by various private and public schools, and the trucking industry's…

  16. 75 FR 11184 - Agency Forms Undergoing Paperwork Reduction Act Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ... prototype of a cost-effective roll over protective structure (CROPS). Projected retrofit costs for CROPS are.... NIOSH has CROPS prototype designs for five tractors: Ford 3000 series, Ford 4000 series, Ford 8N, Ford... two selected States who use tractors for which a CROPS prototype has been developed by NIOSH....

  17. Instrumentation for measuring energy inputs to implements

    SciTech Connect

    Tompkins, F.D.; Wilhelm, L.R.

    1981-01-01

    A microcomputer-based instrumentation system for monitoring tractor operating parameters and energy inputs to implements was developed and mounted on a 75-power-takeoff-KW tractor. The instrumentation system, including sensors and data handling equipment, is discussed. 10 refs.

  18. 78 FR 7394 - Foreign-Trade Zone 41-Milwaukee, WI; Notification of Proposed Production Activity; CNH America...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ... Foreign-Trade Zones Board Foreign-Trade Zone 41--Milwaukee, WI; Notification of Proposed Production... Milwaukee, grantee of FTZ 41, submitted a notification of proposed production activity on behalf of CNH... are used for the production of tractors and tractor/combine components. Pursuant to 15 CFR...

  19. A Multi-Year Program Plan for the Aerodynamic Design of Heavy Vehicles

    SciTech Connect

    2001-09-01

    The project tasks and deliverables are as follows: Computations and Experiments--(1) Simulation and analysis of a range of generic shapes, simplified to more complex, representative of tractor and integrated tractor-trailer flow characteristics using computational tools, (2) The establishment of an experimental data base for tractor-trailer models for code/computational method development and validation. The first shapes to be considered will be directed towards the investigation of tractor-trailer gaps and mismatch of tractor-trailer heights. (3) The evaluation and documentation of effective computational approaches for application to heavy vehicle aerodynamics based on the benchmark results with existing and advanced computational tools compared to experimental data, and (4) Computational tools and experimental methods for use by industry, National Laboratories, and universities for the aerodynamic modeling of heavy truck vehicles. Evaluation of current and new technologies--(1) The evaluation and documentation of current and new technologies for drag reduction based on published literature and continued communication with the heavy vehicle industry (e.g., identification and prioritization of tractor-trailer drag-sources, blowing and/or suction devices, body shaping, new experimental methods or facilities), and the identification and analysis of tractor and integrated tractor-trailer aerodynamic problem areas and possible solution strategies. (2) Continued industrial site visits. It should be noted that ''CFD tools'' are not only the actual computer codes, but descriptions of appropriate numerical solution methods. Part of the project effort will be to determine the restrictions or avenues for technology transfer.

  20. 26 CFR 1.471-4 - Inventories at cost or market, whichever is lower.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... application of section 263A, and must have otherwise complied with § 1.471-4 (as contained in the 26 CFR part... of cost or market value of the tractor, A compares the cost of the tractor, $10,000, with the market... the lower of cost or market value of the shoes, B compares the cost of the pair of shoes, $210,...

  1. 23 CFR 658.13 - Length.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) in 23 CFR 658.19. (6) Munitions carriers using dromedary equipment. A truck tractor equipped with a... safety regulations at 49 CFR parts 390-399. (2) Boat transporters. (i) Boat transporters are considered... meaning as in 49 CFR 393.5. (iii) Truck tractor-beverage semitrailer combinations shall have the...

  2. Hydrogen sulfide gas emissions in the human-occupied zone during disturbance and removal of stored spent mushroom compost.

    PubMed

    Velusami, B; Curran, T P; Grogan, H M

    2013-10-01

    Hydrogen sulfide (H2S) gas levels were monitored in the human-occupied zone at four spent mushroom compost (SMC) storage sites during removal of SMC for application on agricultural land. During SMC removal operations, H2S gas monitors were mounted on the outside of the tractor positioned at the SMC periphery, and worn by individual tractor drivers. The highest H2S concentrations (10 s average) detected outside the tractor, at the SMC periphery, and for the tractor driver were, respectively, 454, 249, and 100 ppm for the outdoor sites and 214, 75, and 51 ppm for the indoor sites. The highest short-term exposure values (STEV over a 15 min period) outside the tractor at the SMC periphery, and for the tractor driver were 147, 55, and 86 ppm for the outdoor sites and 19, 9, and 10 ppm for the indoor sites. The values exceeded the current maximum permissible concentration limit of 10 ppm for all the sites except for the SMC periphery and tractor driver at the indoor sites. Results suggest that H2S levels detected at indoor storage sites during SMC removal are lower compared to outdoor storage sites. Results indicate that there is a substantial health and safety risk associated with working in the vicinity of stored SMC when it is being disturbed and removed for land application, and that the risk is great for the tractor driver. This article discusses possible control measures and lists recommendations to reduce the risks. PMID:24673036

  3. 23 CFR 658.13 - Length.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... safety regulations at 49 CFR parts 390-399. (2) Boat transporters. (i) Boat transporters are considered... meaning as in 49 CFR 393.5. (iii) Truck tractor-beverage semitrailer combinations shall have the same...) in 23 CFR 658.19. (6) Munitions carriers using dromedary equipment. A truck tractor equipped with...

  4. Array Of Rockets For Multicrewmember Evacuation

    NASA Technical Reports Server (NTRS)

    Allen, Margaret A.

    1990-01-01

    Emergency egress system undergoing development for aircraft and aerospace vehicles uses fixed array of tractor rockets to eject crewmembers. Crewmembers hook up to tractor rockets and fire them unaided. Positioned as unit in ready-to-use orientation during flight operations. On ground, swung out of way. Rocket array also mounts under exit hatch, serving as egress ramp.

  5. General Biology and Current Management Approaches of Soft Scale Pests (Hemiptera: Coccidae)

    PubMed Central

    Camacho, Ernesto Robayo; Chong, Juang-Horng

    2015-01-01

    We summarize the economic importance, biology, and management of soft scales, focusing on pests of agricultural, horticultural, and silvicultural crops in outdoor production systems and urban landscapes. We also provide summaries on voltinism, crawler emergence timing, and predictive models for crawler emergence to assist in developing soft scale management programs. Phloem-feeding soft scale pests cause direct (e.g., injuries to plant tissues and removal of nutrients) and indirect damage (e.g., reduction in photosynthesis and aesthetic value by honeydew and sooty mold). Variations in life cycle, reproduction, fecundity, and behavior exist among congenerics due to host, environmental, climatic, and geographical variations. Sampling of soft scale pests involves sighting the insects or their damage, and assessing their abundance. Crawlers of most univoltine species emerge in the spring and the summer. Degree-day models and plant phenological indicators help determine the initiation of sampling and treatment against crawlers (the life stage most vulnerable to contact insecticides). The efficacy of cultural management tactics, such as fertilization, pruning, and irrigation, in reducing soft scale abundance is poorly documented. A large number of parasitoids and predators attack soft scale populations in the field; therefore, natural enemy conservation by using selective insecticides is important. Systemic insecticides provide greater flexibility in application method and timing, and have longer residual longevity than contact insecticides. Application timing of contact insecticides that coincides with crawler emergence is most effective in reducing soft scale abundance. PMID:26823990

  6. Space Shuttle Discovery rolls out to the launch pad

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The Space Shuttle Discovery, atop the mobile launcher platform and crawler-transporter, begins the climb up the ramp to Launch Pad 39B. Traveling at 1 mph, the crawler-transporter takes about five hours to cover the 4.2 miles from the Vehicle Assembly Building to the launch pad. Special levelers on the crawler- transporter keep the Space Shuttle vertical within plus or minus 10 minutes of arc about the dimensions of a basketball. Liftoff of Discovery on mission STS-96 is targeted for May 20 at 9:32 a.m. EDT. STS-96 is a logistics and resupply mission for the International Space Station, carrying such payloads as a Russian crane, the Strela; a U.S.-built crane; the Spacehab Oceaneering Space System Box (SHOSS), a logistics items carrier; and STARSHINE, a student-led experiment.

  7. The application of virtual prototyping methods to determine the dynamic parameters of mobile robot

    NASA Astrophysics Data System (ADS)

    Kurc, Krzysztof; Szybicki, Dariusz; Burghardt, Andrzej; Muszyńska, Magdalena

    2016-04-01

    The paper presents methods used to determine the parameters necessary to build a mathematical model of an underwater robot with a crawler drive. The parameters present in the dynamics equation will be determined by means of advanced mechatronic design tools, including: CAD/CAE software andMES modules. The virtual prototyping process is described as well as the various possible uses (design adaptability) depending on the optional accessories added to the vehicle. A mathematical model is presented to show the kinematics and dynamics of the underwater crawler robot, essential for the design stage.

  8. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, Paul R [Richland, WA

    1986-01-01

    A portable, hand held electric arc saw has a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc to erode a workpiece. Electric current is supplied to the blade by biased brushes and a slip ring which are mounted in the frame. A pair of freely movable endless belts in the form of crawler treads stretched between two pulleys are used to facilitate movement of the electric arc saw. The pulleys are formed of dielectric material to electrically insulate the crawler treads from the frame.

  9. Reinforcement learning: Solving two case studies

    NASA Astrophysics Data System (ADS)

    Duarte, Ana Filipa; Silva, Pedro; dos Santos, Cristina Peixoto

    2012-09-01

    Reinforcement Learning algorithms offer interesting features for the control of autonomous systems, such as the ability to learn from direct interaction with the environment, and the use of a simple reward signalas opposed to the input-outputs pairsused in classic supervised learning. The reward signal indicates the success of failure of the actions executed by the agent in the environment. In this work, are described RL algorithmsapplied to two case studies: the Crawler robot and the widely known inverted pendulum. We explore RL capabilities to autonomously learn a basic locomotion pattern in the Crawler, andapproach the balancing problem of biped locomotion using the inverted pendulum.

  10. Selecting target populations for ROPS retrofit programs in Pennsylvania and Vermont.

    PubMed

    Yoder, A M; Sorensen, J A; Foster, F; Myers, M; Murphy, D; Cook, G; May, J; Jenkins, P

    2013-07-01

    Agriculture has the highest injury and fatality rates when compared with other U.S. industries, and tractor overturns remain the leading cause of agricultural fatalities. Rollover protection structures (ROPS) are the only proven devices to protect a tractor operator in the event of an overturn. These devices are 99% effective when used with a seatbelt. Nearly 49% of tractors in the U.S. are not equipped with a ROPS. Interventions such as social marketing, community awareness campaigns, and financial incentives have been directed at encouraging farmers to install ROPS on their unprotected tractors. The purpose of this study was to conduct similar comparisons of ROPS protection and readiness to retrofit in different segments of the Vermont and Pennsylvania farm communities. A telephone survey was used to collect data on ROPS prevalence, farm demographic characteristics, and farmer's stage of change relative to installing ROPS on farm tractors. Our data provide new and unique information on the prevalence of ROPS-equipped tractors relative to commodity, farm size, and a variety of other demographic variables. Extrapolating from these data, the commodities studied account for roughly 162,072 tractors across the two states. Of these, 85,927 (53%) do not have ROPS. Of these unprotected tractors, 77,203 are in Pennsylvania and 8,724 are in Vermont. Our other two research questions dealt with the farmer's stage of change and possible ways to segment this population. The stage of change portion of our work demonstrates that most Pennsylvania and Vermont farmers are not contemplating ROPS retrofitting in the near future. Since no major differences were found in the stage of change, the number of unprotected tractors was examined for each of the commodity groups. In Pennsylvania, 29% of all unprotected tractors were found on cash crop farms. This trend was even more apparent on smaller farms than large farms. This led to the selection of smaller cash crop farms as the target

  11. Using radar to help mitigate truck overturn incidents on US interstate highways

    NASA Astrophysics Data System (ADS)

    Greneker, Eugene F.; Rausch, Ekkehart O.

    2004-08-01

    The operations of tractor-trailers, mixed with other vehicles on US interstates, has resulted in a number of major tractor-trailer overturn events which often cause traffic to stop for hours along a major traffic corridor because the wreckage physically blocks the corridor. In some cases, the blockage remains for a day or more if toxic substances are being carried by the tractor-trailer. Mixed vehicle use of the interstates coupled with the fact that some tractor-trailers with high center of gravity loads are driven too fast ensure that the overturn events experienced to date will continue. In a previous SPIE paper, the Georgia Tech Research Institute researchers demonstrated that an X-band radar (10.5 GHz) could detect the oscillation frequency of tractor-trailer trucks within 1,000 feet of the radar. This radar was used to control a vibration damper on a bridge to provide longer bridge life. Previous studies conducted by GTRI show that tractor-trailer trucks reflect several orders of magnitude more energy than passenger vehicles, vans and other smaller trucks. In many cases, the large tractor-trailer truck radar signature alone could be used to identify the trucks from the other traffic. However, since non-ranging homodyne radar was being used, it was not known if smaller radar cross section targets that were closer to the radar than the tractor-trailer trucks would have a larger radar signature. This paper examines the issues associated with identifying tractor-trailer truck radar signatures from the radar signatures of other vehicles within the antenna beam of a non-ranging homodyne radar.

  12. Locomotor Experience and Use of Social Information Are Posture Specific

    ERIC Educational Resources Information Center

    Adolph, Karen E.; Tamis-LeMonda, Catherine S.; Ishak, Shaziela; Karasik, Lana B.; Lobo, Sharon A.

    2008-01-01

    The authors examined the effects of locomotor experience on infants' perceptual judgments in a potentially risky situation--descending steep and shallow slopes--while manipulating social incentives to determine where perceptual judgments are most malleable. Twelve-month-old experienced crawlers and novice walkers were tested on an adjustable…

  13. Design and Empirical Evaluation of Search Software for Legal Professionals on the WWW.

    ERIC Educational Resources Information Center

    Dempsey, Bert J.; Vreeland, Robert C.; Sumner, Robert G., Jr.; Yang, Kiduk

    2000-01-01

    Discussion of effective search aids for legal researchers on the World Wide Web focuses on the design and evaluation of two software systems developed to explore models for browsing and searching across a user-selected set of Web sites. Describes crawler-enhanced search engines, filters, distributed full-text searching, and natural language…

  14. Quality Dimensions of Internet Search Engines.

    ERIC Educational Resources Information Center

    Xie, M.; Wang, H.; Goh, T. N.

    1998-01-01

    Reviews commonly used search engines (AltaVista, Excite, infoseek, Lycos, HotBot, WebCrawler), focusing on existing comparative studies; considers quality dimensions from the customer's point of view based on a SERVQUAL framework; and groups these quality expectations in five dimensions: tangibles, reliability, responsiveness, assurance, and…

  15. Internet Search Engines - Fluctuations in Document Accessibility.

    ERIC Educational Resources Information Center

    Mettrop, Wouter; Nieuwenhuysen, Paul

    2001-01-01

    Reports an empirical investigation of the consistency of retrieval through Internet search engines. Evaluates 13 engines: AltaVista, EuroFerret, Excite, HotBot, InfoSeek, Lycos, MSN, NorthernLight, Snap, WebCrawler, and three national Dutch engines: Ilse, Search.nl and Vindex. The focus is on a characteristic related to size: the degree of…

  16. Crawling and walking infants elicit different verbal responses from mothers.

    PubMed

    Karasik, Lana B; Tamis-Lemonda, Catherine S; Adolph, Karen E

    2014-05-01

    We examined mothers' verbal responses to their crawling or walking infants' object sharing (i.e. bids). Fifty mothers and their 13-month-olds were observed for 1 hour at home. Infants bid from a stationary position or they bid after carrying the object to their mothers. Mothers responded with affirmations (e.g. 'thank you'), descriptions ('red box'), or action directives ('open it'). Infants' locomotor status and the form of their bids predicted how mothers responded. Mothers of walkers responded with action directives more often than mothers of crawlers. Notably, differences in the responses of mothers of walkers versus those of crawlers were explained by differences in bid form between the two groups of infants. Walkers were more likely to engage in moving bids than crawlers, who typically shared objects from stationary positions. When crawlers displayed moving bids, their mothers offered action directives just as often as did mothers of walkers. Findings illustrate developmental cascades, wherein Infants' locomotor status affects how infants share objects with mothers, which in turn shapes mothers' verbal responses.

  17. KSC-05PD-0606

    NASA Technical Reports Server (NTRS)

    2005-01-01

    KENNEDY SPACE CENTER, FLA. As Space Shuttle Discovery creeps along the crawlerway toward the horizon, and Launch Pad 39B at NASAs Kennedy Space Center, media and workers in the foreground appear as ants. First motion of the Shuttle out of the Vehicle Assembly Building (VAB) was at 2:04 p.m. EDT. The Mobile Launcher Platform is moved by the Crawler-Transporter underneath. The Crawler is 20 feet high, 131 feet long and 114 feet wide. It moves on eight tracks, each containing 57 shoes, or cleats, weighing one ton each. Loaded with the Space Shuttle, the Crawler can move at a maximum speed of approximately 1 mile an hour. A leveling system in the Crawler keeps the Shuttle vertical while negotiating the 5 percent grade leading to the top of the launch pad. Launch of Discovery on its Return to Flight mission, STS- 114, is targeted for May 15 with a launch window that extends to June 3. During its 12-day mission, Discoverys seven-person crew will test new hardware and techniques to improve Shuttle safety, as well as deliver supplies to the International Space Station. Discovery was moved on March 29 from the Orbiter Processing Facility to the VAB and attached to its propulsion elements, a redesigned ET and twin SRBs.

  18. Web Archiving for the Rest of Us: How to Collect and Manage Websites Using Free and Easy Software

    ERIC Educational Resources Information Center

    Dunn, Katharine; Szydlowski, Nick

    2009-01-01

    Large-scale projects such as the Internet Archive (www.archive.org) send out crawlers to gather snapshots of much of the web. This massive collection of archived websites may include content of interest to one's patrons. But if librarians want to control exactly when and what is archived, relying on someone else to do the archiving is not ideal.…

  19. Transition from Crawling to Walking and Infants' Actions with Objects and People

    ERIC Educational Resources Information Center

    Karasik, Lana B.; Tamis-LeMonda, Catherine S.; Adolph, Karen E.

    2011-01-01

    Associations between infants' transition to walking and object activities were examined. Fifty infants were observed longitudinally during home observations. At 11 months, all infants were crawlers; at 13 months, half became walkers. Over age, infants increased their total time with objects and frequency of sharing objects with mothers.…

  20. Indexing and Retrieval for the Web.

    ERIC Educational Resources Information Center

    Rasmussen, Edie M.

    2003-01-01

    Explores current research on indexing and ranking as retrieval functions of search engines on the Web. Highlights include measuring search engine stability; evaluation of Web indexing and retrieval; Web crawlers; hyperlinks for indexing and ranking; ranking for metasearch; document structure; citation indexing; relevance; query evaluation;…

  1. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, C.F.; Howard, B.D.

    1994-01-01

    Pipe crawlers, pipe inspection {open_quotes}rabbits{close_quotes} and similar vehicles are widely used for inspecting the interior surfaces of piping systems, storage tanks and process vessels for damaged or flawed structural features. This paper describes the design of a flexible, modular ultrasonic pipe inspection apparatus.

  2. 241-AY-102 Leak Detection Pit Drain Line Inspection Report

    SciTech Connect

    Boomer, Kayle D.; Engeman, Jason K.; Gunter, Jason R.; Joslyn, Cameron C.; Vazquez, Brandon J.; Venetz, Theodore J.; Garfield, John S.

    2014-01-20

    This document provides a description of the design components, operational approach, and results from the Tank AY-102 leak detection pit drain piping visual inspection. To perform this inspection a custom robotic crawler with a deployment device was designed, built, and operated by IHI Southwest Technologies, Inc. for WRPS to inspect the 6-inch leak detection pit drain line.

  3. Endeavour, Orbiter Vehicle (OV) 105, roll out to KSC Launch Complex Pad 39B

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Endeavour, Orbiter Vehicle (OV) 105, roll out to Kennedy Space Center (KSC) Launch Complex (LC) Pad 39B via crawler transport. Scene is framed by palm trees on either side. View provided by KSC with alternate number KSC-92PC-553.

  4. Crawling and walking infants elicit different verbal responses from mothers.

    PubMed

    Karasik, Lana B; Tamis-Lemonda, Catherine S; Adolph, Karen E

    2014-05-01

    We examined mothers' verbal responses to their crawling or walking infants' object sharing (i.e. bids). Fifty mothers and their 13-month-olds were observed for 1 hour at home. Infants bid from a stationary position or they bid after carrying the object to their mothers. Mothers responded with affirmations (e.g. 'thank you'), descriptions ('red box'), or action directives ('open it'). Infants' locomotor status and the form of their bids predicted how mothers responded. Mothers of walkers responded with action directives more often than mothers of crawlers. Notably, differences in the responses of mothers of walkers versus those of crawlers were explained by differences in bid form between the two groups of infants. Walkers were more likely to engage in moving bids than crawlers, who typically shared objects from stationary positions. When crawlers displayed moving bids, their mothers offered action directives just as often as did mothers of walkers. Findings illustrate developmental cascades, wherein Infants' locomotor status affects how infants share objects with mothers, which in turn shapes mothers' verbal responses. PMID:24314018

  5. The Influence That Javascript™ Has on the Visibility of a Website to Search Engines--A Pilot Study

    ERIC Educational Resources Information Center

    Weideman, M.; Schwenke, F.

    2006-01-01

    Introduction: In this research project, an empirical pilot study on the relationship between JavaScript™ usage and Website visibility was carried out. The main purpose was to establish whether JavaScript™- based hyperlinks attract or repel crawlers, resulting in an increase or decrease in Website visibility. Method: A literature survey has…

  6. 29 CFR 1926.1400 - Scope.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... Such equipment includes, but is not limited to: Articulating cranes (such as knuckle-boom cranes); crawler cranes; floating cranes; cranes on barges; locomotive cranes; mobile cranes (such as wheel-mounted...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1400...

  7. Users' Perceptions of the Web As Revealed by Transaction Log Analysis.

    ERIC Educational Resources Information Center

    Moukdad, Haidar; Large, Andrew

    2001-01-01

    Describes the results of a transaction log analysis of a Web search engine, WebCrawler, to analyze user's queries for information retrieval. Results suggest most users do not employ advanced search features, and the linguistic structure often resembles a human-human communication model that is not always successful in human-computer communication.…

  8. 9 CFR 88.1 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... profit via conveyance on any highway or public road. Conveyance. Trucks, tractors, trailers, or... incidental to his or her principal activity of production agriculture (production of food or fiber)....

  9. 49 CFR 107.620 - Recordkeeping requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... identified as the “U.S. DOT Hazmat Reg. No.” on board each truck and truck tractor (not including trailers... or another document bearing the current registration number identified as the “U.S. DOT Hazmat...

  10. 49 CFR 107.620 - Recordkeeping requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... identified as the “U.S. DOT Hazmat Reg. No.” on board each truck and truck tractor (not including trailers... or another document bearing the current registration number identified as the “U.S. DOT Hazmat...

  11. 49 CFR 107.620 - Recordkeeping requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... identified as the “U.S. DOT Hazmat Reg. No.” on board each truck and truck tractor (not including trailers... or another document bearing the current registration number identified as the “U.S. DOT Hazmat...

  12. 49 CFR 107.620 - Recordkeeping requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... identified as the “U.S. DOT Hazmat Reg. No.” on board each truck and truck tractor (not including trailers... or another document bearing the current registration number identified as the “U.S. DOT Hazmat...

  13. 49 CFR 107.620 - Recordkeeping requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... identified as the “U.S. DOT Hazmat Reg. No.” on board each truck and truck tractor (not including trailers... or another document bearing the current registration number identified as the “U.S. DOT Hazmat...

  14. 16 CFR 20.0 - Scope and purpose of the guides.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... used parts designed for use in automobiles, trucks, motorcycles, tractors, or similar self-propelled..., fan clutches, fuel injectors, fuel pumps, front wheel drive axles, generators, master cylinders, oil... Labeling Guides, 16 CFR part 228.)...

  15. 16 CFR 20.0 - Scope and purpose of the guides.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... used parts designed for use in automobiles, trucks, motorcycles, tractors, or similar self-propelled..., fan clutches, fuel injectors, fuel pumps, front wheel drive axles, generators, master cylinders, oil... Labeling Guides, 16 CFR part 228.)...

  16. 16 CFR 20.0 - Scope and purpose of the guides.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... used parts designed for use in automobiles, trucks, motorcycles, tractors, or similar self-propelled..., fan clutches, fuel injectors, fuel pumps, front wheel drive axles, generators, master cylinders, oil... Labeling Guides, 16 CFR part 228.)...

  17. 50 CFR 37.31 - Environmental protection.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... or prohibit exploratory activities in these areas and, in accordance with 36 CFR part 800, thereby... Caterpillar tractors, or their equivalent. They shall be operated only in the winter and where there...

  18. 50 CFR 37.31 - Environmental protection.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... or prohibit exploratory activities in these areas and, in accordance with 36 CFR part 800, thereby... Caterpillar tractors, or their equivalent. They shall be operated only in the winter and where there...

  19. 50 CFR 37.31 - Environmental protection.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... or prohibit exploratory activities in these areas and, in accordance with 36 CFR part 800, thereby... Caterpillar tractors, or their equivalent. They shall be operated only in the winter and where there...

  20. 50 CFR 37.31 - Environmental protection.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... or prohibit exploratory activities in these areas and, in accordance with 36 CFR part 800, thereby... Caterpillar tractors, or their equivalent. They shall be operated only in the winter and where there...

  1. 50 CFR 37.31 - Environmental protection.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... or prohibit exploratory activities in these areas and, in accordance with 36 CFR part 800, thereby... Caterpillar tractors, or their equivalent. They shall be operated only in the winter and where there...

  2. Fifth wheel modification assembly, Issue U

    SciTech Connect

    Arning, C.

    1994-12-31

    This report consists of one engineering drawing showing modifications to the Fifth Wheel System for a semi-tractor trailer truck. Notes give instructions for installation of some items, where other items may be purchased, testing instructions, and shipping instructions.

  3. 49 CFR 393.28 - Wiring systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... Electrical wiring shall be installed and maintained to conform to SAE J1292—Automobile, Truck, Truck-Tractor, Trailer, and Motor Coach Wiring, October 1981, except the jumper cable plug and receptacle need...

  4. 49 CFR 393.28 - Wiring systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... Electrical wiring shall be installed and maintained to conform to SAE J1292—Automobile, Truck, Truck-Tractor, Trailer, and Motor Coach Wiring, October 1981, except the jumper cable plug and receptacle need...

  5. 49 CFR 393.28 - Wiring systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    .... Electrical wiring shall be installed and maintained to conform to SAE J1292—Automobile, Truck, Truck-Tractor, Trailer, and Motor Coach Wiring, October 1981, except the jumper cable plug and receptacle need...

  6. 49 CFR 393.28 - Wiring systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    .... Electrical wiring shall be installed and maintained to conform to SAE J1292—Automobile, Truck, Truck-Tractor, Trailer, and Motor Coach Wiring, October 1981, except the jumper cable plug and receptacle need...

  7. 49 CFR 393.43 - Breakaway and emergency braking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., separate. (c) Emergency brake requirements, vacuum brakes. Every truck tractor and truck when used for towing other vehicles equipped with vacuum brakes, shall have, in addition to the single control...

  8. 49 CFR 393.43 - Breakaway and emergency braking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., separate. (c) Emergency brake requirements, vacuum brakes. Every truck tractor and truck when used for towing other vehicles equipped with vacuum brakes, shall have, in addition to the single control...

  9. 30. Photo copy of photograph, (original in Forest Service Office, ...

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

    30. Photo copy of photograph, (original in Forest Service Office, Elkins, WV, 'tractor with cultivator operating'), photographer unknown, ca. 1938. VIEW SOUTHEAST, CULTIVATING SEEDLING TRANSPLANTS. - Parsons Nursery, South side of U.S. Route 219, Parsons, Tucker County, WV

  10. Farm Safety (For Parents)

    MedlinePlus

    ... wheels or blind spots. Because adults who are operating machinery may be unable to see or hear ... a tractor and farm vehicle safety course before operating farm vehicles. Finally, teach older kids how to ...

  11. 16 CFR 20.0 - Scope and purpose of the guides.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... used parts designed for use in automobiles, trucks, motorcycles, tractors, or similar self-propelled..., fan clutches, fuel injectors, fuel pumps, front wheel drive axles, generators, master cylinders, oil... Labeling Guides, 16 CFR part 228.)...

  12. Recent Projects in the KSC Applied Physics Lab

    NASA Technical Reports Server (NTRS)

    Starr, Stanley

    2013-01-01

    Topics include: Shuttle heritage; ISRU /RESOLVE: a) Payload for Lunar Lander/Rover on Polar Areas of Moon. b) Avionics/Software. New Technologies for Exploration: a) Radiation Shielding work. b) Cooperative Tractor Beams.

  13. Operational considerations in specifying legal weight vehicles for the highway transport of spent nuclear fuel

    SciTech Connect

    Hill, C V; Rutenkroger, E O; Ratledge, J E

    1990-01-01

    This paper presents the results of a research project in which tractor manufacturers and carrier companies were interviewed to gather information on operational concerns in specifying a tractor to haul legal weight spent fuel casks. The system was assumed to operate very close to the 80,000 pound legal weight limit. Safety, performance, reliability, and maintainability of equipment were factors given particular attention. The interaction between driver fatigue, safety, and equipment was also discussed. Innovative operating strategies that could save weight were discussed. The paper concluded that operational considerations require that planners working with standard off-the-shelf tractor equipment should allow at least 17,350 pounds for the weight of the tractor as a starting point from which further weight reduction analysis can proceed. 4 refs., 3 figs.

  14. 22 CFR 228.13 - Special source rules requiring procurement from the United States.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... industrial vehicles for materials handling and earthmoving, such as lift trucks, tractors, graders, scrapers, off-the-highway trucks (such as off-road dump trucks) and other vehicles that are not designed...

  15. 3. DETAIL VIEW OF DIRECT DRIVE STERLING 'DOLPHIN T' MODEL ...

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

    3. DETAIL VIEW OF DIRECT DRIVE STERLING 'DOLPHIN T' MODEL 4 CYLINDER, GASOLINE TRACTOR-TYPE ENGINE WITH FALKBIBBY FLEXIBLE COUPLING - Central Railroad of New Jersey, Newark Bay Lift Bridge, Spanning Newark Bay, Newark, Essex County, NJ

  16. Role of telecommunications in precision agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision agriculture has been made possible by the confluence of several technologies: geographic positioning systems, geographic information systems, image analysis software, low-cost microcomputer-based variable rate controller/recorders, and precision tractor guidance systems. While these techn...

  17. 29 CFR Appendix A to Subpart C of... - Employee Operating Instructions

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... operating the tractor near ditches, embankments, and holes. 3. Reduce speed when turning, crossing slopes, and on rough, slick, or muddy surfaces. 4. Stay off slopes too steep for safe operation. 5....

  18. 29 CFR Appendix A to Subpart C of... - Employee Operating Instructions

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... operating the tractor near ditches, embankments, and holes. 3. Reduce speed when turning, crossing slopes, and on rough, slick, or muddy surfaces. 4. Stay off slopes too steep for safe operation. 5....

  19. 26 CFR 1.263(a)-2 - Amounts paid to acquire or produce tangible property.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    .... Except as provided in paragraphs (j)(1) and (j)(2) of this section, § 1.263(a)-2 as contained in 26 CFR... plant where it manufactures widgets. Y purchases a tractor loader to move raw materials into and...

  20. 40 CFR 1037.655 - Post-useful life vehicle modifications.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... technical basis has the meaning given in 40 CFR 1068.30. This generally requires you to have information... to its expiration point. (2) No person may remove aerodynamic fairings from tractors that are...

  1. 40 CFR 1037.655 - Post-useful life vehicle modifications.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... technical basis has the meaning given in 40 CFR 1068.30. This generally requires you to have information... to its expiration point. (2) No person may remove aerodynamic fairings from tractors that are...

  2. 40 CFR 1037.655 - Post-useful life vehicle modifications.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... technical basis has the meaning given in 40 CFR 1068.30. This generally requires you to have information... to its expiration point. (2) No person may remove aerodynamic fairings from tractors that are...

  3. 29 CFR 4.117 - Work subject to requirements of Walsh-Healey Act.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... automobile, truck, or other vehicle, construction equipment, tractor, crane, aerospace, air conditioning and..., lubrication, tune-up, or replacement of internal parts of equipment listed in paragraphs (b)(3)(i), (ii),...

  4. 29 CFR 4.117 - Work subject to requirements of Walsh-Healey Act.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... automobile, truck, or other vehicle, construction equipment, tractor, crane, aerospace, air conditioning and..., lubrication, tune-up, or replacement of internal parts of equipment listed in paragraphs (b)(3)(i), (ii),...

  5. 29 CFR 4.117 - Work subject to requirements of Walsh-Healey Act.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... automobile, truck, or other vehicle, construction equipment, tractor, crane, aerospace, air conditioning and..., lubrication, tune-up, or replacement of internal parts of equipment listed in paragraphs (b)(3)(i), (ii),...

  6. 29 CFR 4.117 - Work subject to requirements of Walsh-Healey Act.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... automobile, truck, or other vehicle, construction equipment, tractor, crane, aerospace, air conditioning and..., lubrication, tune-up, or replacement of internal parts of equipment listed in paragraphs (b)(3)(i), (ii),...

  7. 29 CFR 4.117 - Work subject to requirements of Walsh-Healey Act.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... automobile, truck, or other vehicle, construction equipment, tractor, crane, aerospace, air conditioning and..., lubrication, tune-up, or replacement of internal parts of equipment listed in paragraphs (b)(3)(i), (ii),...

  8. 49 CFR 383.113 - Required skills.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) Rear of vehicle; and (ix) Special features of tractor trailer, school bus, or coach/transit bus, if... vehicles from passing on the wrong side, as well as to prevent problems caused by off-tracking; (6)...

  9. 49 CFR 383.113 - Required skills.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) Rear of vehicle; and (ix) Special features of tractor trailer, school bus, or coach/transit bus, if... vehicles from passing on the wrong side, as well as to prevent problems caused by off-tracking; (6)...

  10. 49 CFR 383.113 - Required skills.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Rear of vehicle; and (ix) Special features of tractor trailer, school bus, or coach/transit bus, if... vehicles from passing on the wrong side, as well as to prevent problems caused by off-tracking; (6)...

  11. 49 CFR 383.113 - Required skills.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) Rear of vehicle; and (ix) Special features of tractor trailer, school bus, or coach/transit bus, if... vehicles from passing on the wrong side, as well as to prevent problems caused by off-tracking; (6)...

  12. 49 CFR 387.401 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... RESPONSIBILITY FOR MOTOR CARRIERS Surety Bonds and Policies of Insurance for Freight Forwarders § 387.401..., tractor, trailer, or semitrailer propelled or drawn by mechanical power and used to transport...

  13. 49 CFR 387.401 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... RESPONSIBILITY FOR MOTOR CARRIERS Surety Bonds and Policies of Insurance for Freight Forwarders § 387.401..., tractor, trailer, or semitrailer propelled or drawn by mechanical power and used to transport...

  14. 49 CFR 387.401 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... RESPONSIBILITY FOR MOTOR CARRIERS Surety Bonds and Policies of Insurance for Freight Forwarders § 387.401..., tractor, trailer, or semitrailer propelled or drawn by mechanical power and used to transport...

  15. 49 CFR 393.28 - Wiring systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... Electrical wiring shall be installed and maintained to conform to SAE J1292—Automobile, Truck, Truck-Tractor... conform to SAE J560. The reference to SAE J1292 shall not be construed to require circuit protection...

  16. 49 CFR 393.100 - Which types of commercial motor vehicles are subject to the cargo securement standards of this...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... trucks, truck tractors, semitrailers, full trailers, and pole trailers. (b) Prevention against loss of..., spilling, blowing or falling from the motor vehicle. (c) Prevention against shifting of load. Cargo must...

  17. 75 FR 82026 - Granting of Request for Early Termination of the Waiting Period Under the Premerger Notification...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-29

    .... Jung. G Michigan Tractor and Machinery Company, Inc. 20110332 G Riverstone/Carlyle Global Energy and... Quality Forming, Inc. 20110362 G Carl C. Icahn. G Reorganized MGM Holdings Inc. G Reorganized MGM...

  18. A Guide to Energy Savings - For the Field Crops Producer.

    ERIC Educational Resources Information Center

    Schienbein, Allen

    This booklet gives a brief overview of energy use in field crop production and gives examples of cutting costs of fertilizer use, irrigation, grain drying, tobacco drying, forate production, and tractor and truck use. Recordkeeping is also discussed. (BB)

  19. The Mechanization of Agriculture.

    ERIC Educational Resources Information Center

    Rasmussen, Wayne D.

    1982-01-01

    Discusses technological innovations affecting the economic and social basis of farm life, focusing on trends, farm equipment (plows, reaping tools, tractors, and harvesters), productivity, and influence of computers in all phases of agribusiness. (JN)

  20. Keeping Teachers Up-to-Date in Ag Mechanics

    ERIC Educational Resources Information Center

    Bruwelheide, Kenneth L.

    1977-01-01

    Describes one of Montana State University's Agricultural and Industrial Education Department teacher workshops for vocational agriculture teachers. The planning, organization, and evaluation of the workshop (which covered farm tractor maintenance) are briefly described. (SH)