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Sample records for roll para lingotamento

  1. CONTROL FOR ROLLING MILL

    DOEpatents

    Shuck, A.B.; Shaw, W.C.

    1961-06-20

    A plutonium-rolling apparatus is patented that has two sets of feed rolls, shaping rolls between the feed rolls, and grippers beyond the feed rolls, which ready a workpiece for a new pass through the shaping rolls by angularly shifting the workpiece about its axis or transversely moving it on a line parallel to the axes of the shaping rolls. Actuation of each gripper for gripping or releasing the workpiece is produced by the relative positions assumed by the feed rolls adjacent to the gripper as the workpiece enters or leaves the feed rolls.

  2. Rolling Uphill

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2017-04-01

    In a recent letter to this journal, Mungan noted that translational energy can be converted into gravitational potential energy when an object is projected vertically, but rotational energy is not usually converted in this manner. As an exception, he gave an example where "a ball initially rolling without slipping will travel higher up a rough ramp than it will up a frictionless ramp." However, such a result is unlikely to be observed in practice. A better example would be a ball spinning rapidly forwards as it slides up the ramp, since the friction force on the ball then acts in a direction up the ramp.

  3. Rolling-Element Bearings

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Anderson, W. J.

    1983-01-01

    Rolling element bearings are a precision, yet simple, machine element of great utility. A brief history of rolling element bearings is reviewed and the type of rolling element bearings, their geometry and kinematics, as well as the materials they are made from and the manufacturing processes they involve are described. Unloaded and unlubricated rolling element bearings, loaded but unlubricated rolling element bearings and loaded and lubricated rolling element bearings are considered. The recognition and understanding of elastohydrodynamic lubrication covered, represents one of the major development in rolling element bearings.

  4. Internal roll compression system

    DOEpatents

    Anderson, Graydon E.

    1985-01-01

    This invention is a machine for squeezing water out of peat or other material of low tensile strength; the machine including an inner roll eccentrically positioned inside a tubular outer roll, so as to form a gradually increasing pinch area at one point therebetween, so that, as the rolls rotate, the material is placed between the rolls, and gets wrung out when passing through the pinch area.

  5. Understanding Rolle's Theorem

    ERIC Educational Resources Information Center

    Parameswaran, Revathy

    2009-01-01

    This paper reports on an experiment studying twelfth grade students' understanding of Rolle's Theorem. In particular, we study the influence of different concept images that students employ when solving reasoning tasks related to Rolle's Theorem. We argue that students' "container schema" and "motion schema" allow for rich…

  6. Effect of Roll Material on Surface Quality of Rolled Aluminum

    NASA Astrophysics Data System (ADS)

    Zhao, Qi

    The surface defects of aluminum alloys that have undergone hot rolling were studied. The effects of different roll materials, of the number of rolling passes and of lubrication on surface defects of hot rolled aluminum alloys were investigated by laboratory hot rolling. Two different aluminum alloys, Al-Mn and Al-Mg, were each rolled against three different steel alloy rolls, AISI 52100, AISI 440C and AISI D2. The results showed that different roll materials do affect the morphology of the mating aluminum alloy surface with apparent surface defects, which included magnesium and oxygen rich dark regions on both alloys. The carbide protrusions in 440C and D2 steel rolls are confirmed to be responsible for the dark, rich magnesium and oxygen regions on both the rolled Al-Mn and Al-Mg alloy surfaces. As the number of passes increases, Mg and O deposit in the form of patches and grain boundaries near the surface area.

  7. Spray Rolling Aluminum Strip

    SciTech Connect

    Lavernia, E.J.; Delplanque, J-P; McHugh, K.M.

    2006-05-10

    Spray forming is a competitive low-cost alternative to ingot metallurgy for manufacturing ferrous and non-ferrous alloy shapes. It produces materials with a reduced number of processing steps, while maintaining materials properties, with the possibility of near-net-shape manufacturing. However, there are several hurdles to large-scale commercial adoption of spray forming: 1) ensuring strip is consistently flat, 2) eliminating porosity, particularly at the deposit/substrate interface, and 3) improving material yield. Through this program, a new strip/sheet casting process, termed spray rolling, has been developed, which is an innovative manufacturing technique to produce aluminum net-shape products. Spray rolling combines the benefits of twin-roll casting and conventional spray forming, showing a promising potential to overcome the above hurdles associated with spray forming. Spray rolling requires less energy and generates less scrap than conventional processes and, consequently, enables the development of materials with lower environmental impacts in both processing and final products. Spray Rolling was developed as a collaborative project between the University of California-Davis, the Colorado School of Mines, the Idaho National Engineering and Environmental Laboratory, and an industry team. The following objectives of this project were achieved: (1) Demonstration of the feasibility of the spray rolling process at the bench-scale level and evaluation of the materials properties of spray rolled aluminum strip alloys; and (2) Demonstration of 2X scalability of the process and documentation of technical hurdles to further scale up and initiate technology transfer to industry for eventual commercialization of the process.

  8. Wear of hot rolling mill rolls: An overview

    NASA Astrophysics Data System (ADS)

    Spuzic, S.; Strafford, K. N.; Subramanian, C.; Savage, G.

    1994-08-01

    Rolling is today one of the most important industrial processes because a greater volume of material is worked by rolling than by any other technique. Roll wear is a multiplex process where mechanical and thermal fatigue combines with impact, abrasion, adhesion and corrosion, which all depend on system interactions rather than material characteristics only. The situation is more complicated in section rolling because of the intricacy of roll geometry. Wear variables and modes are reviewed along with published methods and models used in the study and testing of roll wear. This paper reviews key aspects of roll wear control - roll material properties, roll pass design, and system factors such as temperature, loads and sliding velocity. An overview of roll materials is given including adamites, high Cr materials, high speed tool steels and compound rolls. Non-uniform wear, recognized as the most detrimental phenomenon in section rolling, can be controlled by roll pass design. This can be achieved by computer-aided graphical and statistical analyses of various pass series. Preliminary results obtained from pilot tests conducted using a two-disc hot wear rig and a scratch tester are discussed.

  9. Stochastic disks that roll

    NASA Astrophysics Data System (ADS)

    Holmes-Cerfon, Miranda

    2016-11-01

    We study a model of rolling particles subject to stochastic fluctuations, which may be relevant in systems of nano- or microscale particles where rolling is an approximation for strong static friction. We consider the simplest possible nontrivial system: a linear polymer of three disks constrained to remain in contact and immersed in an equilibrium heat bath so the internal angle of the polymer changes due to stochastic fluctuations. We compare two cases: one where the disks can slide relative to each other and the other where they are constrained to roll, like gears. Starting from the Langevin equations with arbitrary linear velocity constraints, we use formal homogenization theory to derive the overdamped equations that describe the process in configuration space only. The resulting dynamics have the formal structure of a Brownian motion on a Riemannian or sub-Riemannian manifold, depending on if the velocity constraints are holonomic or nonholonomic. We use this to compute the trimer's equilibrium distribution with and without the rolling constraints. Surprisingly, the two distributions are different. We suggest two possible interpretations of this result: either (i) dry friction (or other dissipative, nonequilibrium forces) changes basic thermodynamic quantities like the free energy of a system, a statement that could be tested experimentally, or (ii) as a lesson in modeling rolling or friction more generally as a velocity constraint when stochastic fluctuations are present. In the latter case, we speculate there could be a "roughness" entropy whose inclusion as an effective force could compensate the constraint and preserve classical Boltzmann statistics. Regardless of the interpretation, our calculation shows the word "rolling" must be used with care when stochastic fluctuations are present.

  10. METHOD OF ROLLING URANIUM

    DOEpatents

    Smith, C.S.

    1959-08-01

    A method is described for rolling uranium metal at relatively low temperatures and under non-oxidizing conditions. The method involves the steps of heating the uranium to 200 deg C in an oil bath, withdrawing the uranium and permitting the oil to drain so that only a thin protective coating remains and rolling the oil coated uranium at a temperature of 200 deg C to give about a 15% reduction in thickness at each pass. The operation may be repeated to accomplish about a 90% reduction without edge cracking, checking or any appreciable increase in brittleness.

  11. Rolling through a vacuum

    NASA Astrophysics Data System (ADS)

    van der Schaar, Jan Pieter; Yang, I.-Sheng

    2013-12-01

    We clarify under what conditions slow-roll inflation can continue almost undisturbed, while briefly evolving through a (semi-classically) metastable false vacuum. Furthermore, we look at potential signatures in the primordial power spectrum that could point towards the existence of traversed metastable false vacua. Interestingly, the theoretical constraints for the existence of traversable metastable vacua imply that Planck should be able to detect the resulting features in the primordial power spectrum. In other words, if Planck does not see features this immediately implies the non-existence of metastable false vacua rolled through during the inflationary epoch.

  12. Aircraft roll steering command system

    NASA Technical Reports Server (NTRS)

    Lambregts, Antonius A. (Inventor)

    1985-01-01

    Aircraft roll command signals are generated as a function of the Microwave Landing System based azimuth, groundtrack, groundspeed and azimuth rate or range distance input parameters. On initial approach, roll command signals are inhibited until a minimum roll command requirement is met. As the aircraft approaches the centerline of the runway, the system reverts to a linear track control.

  13. Rolling Spot Welder

    NASA Technical Reports Server (NTRS)

    Wagner, Garret E.; Fonteyne, Steve L.

    1990-01-01

    Wheeled tool speeds tack-welding operations. Spotwelds foil to parts in preparation for brazing. Includes electrode wheel rolling across foil. Welding current in electrode pulsed as electrode moves along, making series of uniformly-spaced low-current spot welds.

  14. GRCop-84 Rolling Parameter Study

    NASA Technical Reports Server (NTRS)

    Loewenthal, William S.; Ellis, David L.

    2008-01-01

    This report is a section of the final report on the GRCop-84 task of the Constellation Program and incorporates the results obtained between October 2000 and September 2005, when the program ended. NASA Glenn Research Center (GRC) has developed a new copper alloy, GRCop-84 (Cu-8 at.% Cr-4 at.% Nb), for rocket engine main combustion chamber components that will improve rocket engine life and performance. This work examines the sensitivity of GRCop-84 mechanical properties to rolling parameters as a means to better define rolling parameters for commercial warm rolling. Experiment variables studied were total reduction, rolling temperature, rolling speed, and post rolling annealing heat treatment. The responses were tensile properties measured at 23 and 500 C, hardness, and creep at three stress-temperature combinations. Understanding these relationships will better define boundaries for a robust commercial warm rolling process. The four processing parameters were varied within limits consistent with typical commercial production processes. Testing revealed that the rolling-related variables selected have a minimal influence on tensile, hardness, and creep properties over the range of values tested. Annealing had the expected result of lowering room temperature hardness and strength while increasing room temperature elongations with 600 C (1112 F) having the most effect. These results indicate that the process conditions to warm roll plate and sheet for these variables can range over wide levels without negatively impacting mechanical properties. Incorporating broader process ranges in future rolling campaigns should lower commercial rolling costs through increased productivity.

  15. Walk and roll robot

    NASA Technical Reports Server (NTRS)

    Wilson, Andrew (Inventor); Punnoose, Andrew (Inventor); Strausser, Katherine (Inventor); Parikh, Neil (Inventor)

    2011-01-01

    A mobile robotic unit features a main body, a plurality of legs for supporting the main body on and moving the main body in forward and reverse directions about a base surface, and a drive assembly. According to an exemplary embodiment each leg includes a respective pivotal hip joint, a pivotal knee joint, and a wheeled foot adapted to roll along the base surface. Also according to an exemplary embodiments the drive assembly includes a motor operatively associated with the hip and knee joints and the wheeled foot for independently driving pivotal movement of the hip joint and the knee joint and rolling motion of the wheeled foot. The hip joint may include a ball-and-socket-type joint interconnecting top portion of the leg to the main body, such that the hip joint is adapted to pivot said leg in a direction transverse to a forward-and-reverse direction.

  16. Shear Roll Mill Reactivation

    DTIC Science & Technology

    2012-09-13

    process equipment sprinkler protection systems , and the 5 psig steam supply serving the building heating and make-up air systems . It also included...control system can be run for maintenance and/or checkout while the fire alarm panel is bypassed. A sprinkler line and gate valve serving the Primac...the 440 v. electrical system providing power for process equipment motors, shear roll hydraulic pump motors, the air compressor motor, as well as

  17. Investigation of thermomechanical behavior of a work roll and of roll life in hot strip rolling

    NASA Astrophysics Data System (ADS)

    Sun, C. G.; Hwang, S. M.; Yun, C. S.; Chung, J. S.

    1998-09-01

    An integrated finite element-based model is presented for the prediction of the steady-state thermomechanical behavior of the roll-strip system and of roll life in hot strip rolling. The model is comprised of basic finite-element models, which are incorporated into an iterative-solution procedure to deal with the interdependence between the thermomechanical behavior of the strip and that of the work roll, which arises from roll-strip contact, as well as with the interdependence between the thermal and mechanical behavior. Comparison is made between the predictions and the measurements to assess solution accuracy. Then, the effect of various process parameters on the detailed aspects of thermomechanical behavior of the work roll and on roll life is investigated via a series of process simulations.

  18. Roll-to-Roll production of carbon nanotubes based supercapacitors

    NASA Astrophysics Data System (ADS)

    Zhu, Jingyi; Childress, Anthony; Karakaya, Mehmet; Roberts, Mark; Arcilla-Velez, Margarita; Podila, Ramakrishna; Rao, Apparao

    2014-03-01

    Carbon nanomaterials provide an excellent platform for electrochemical double layer capacitors (EDLCs). However, current industrial methods for producing carbon nanotubes are expensive and thereby increase the costs of energy storage to more than 10 Wh/kg. In this regard, we developed a facile roll-to-roll production technology for scalable manufacturing of multi-walled carbon nanotubes (MWNTs) with variable density on run-of-the-mill kitchen Al foils. Our method produces MWNTs with diameter (heights) between 50-100 nm (10-100 μm), and a specific capacitance as high as ~ 100 F/g in non-aqueous electrolytes. In this talk, the fundamental challenges involved in EDLC-suitable MWNT growth, roll-to-roll production, and device manufacturing will be discussed along with electrochemical characteristics of roll-to-roll MWNTs. Research supported by NSF CMMI Grant1246800.

  19. Rolling cuff flexible bellows

    DOEpatents

    Lambert, Donald R.

    1985-01-01

    A flexible connector apparatus used to join two stiff non-deformable members, such as piping. The apparatus is provided with one or more flexible sections or assemblies each utilizing a bellows of a rolling cuff type connected between two ridge members, with the bellows being supported by a back-up ring, such that only the curved end sections of the bellows are unsupported. Thus, the bellows can be considered as being of a tube-shaped configuration and thus have high pressure resistance. The components of the flexible apparatus are sealed or welded one to another such that it is fluid tight.

  20. VIEW OF HANDOPERATED ROLLING MILLS ROLLING STANDS FROM LEFT TO ...

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

    VIEW OF HAND-OPERATED ROLLING MILLS ROLLING STANDS FROM LEFT TO RIGHT: THREE HIGH; THREE HIGH; THREE HIGH; THREE HIGH (OPERATED AS A TWO-HIGH); TWO HIGH TWO HIGH MANUFACTURED BY BLAW-KNOX THREE HIGH MANUFACTURED BY LEWIS FOUNDRY AND MACHINE CO. - Cambria Iron Company, Gautier Works, 12" Mill, Clinton Street & Little Conemaugh River, Johnstown, Cambria County, PA

  1. Video Analysis of Rolling Cylinders

    ERIC Educational Resources Information Center

    Phommarach, S.; Wattanakasiwich, P.; Johnston, I.

    2012-01-01

    In this work, we studied the rolling motion of solid and hollow cylinders down an inclined plane at different angles. The motions were captured on video at 300 frames s[superscript -1], and the videos were analyzed frame by frame using video analysis software. Data from the real motion were compared with the theory of rolling down an inclined…

  2. Critical rolling angle of microparticles

    NASA Astrophysics Data System (ADS)

    Farzi, Bahman; Vallabh, Chaitanya K. P.; Stephens, James D.; Cetinkaya, Cetin

    2016-03-01

    At the micrometer-scale and below, particle adhesion becomes particularly relevant as van der Waals force often dominates volume and surface proportional forces. The rolling resistance of microparticles and their critical rolling angles prior to the initiation of free-rolling and/or complete detachment are critical in numerous industrial processes and natural phenomenon involving particle adhesion and granular dynamics. The current work describes a non-contact measurement approach for determining the critical rolling angle of a single microparticle under the influence of a contact-point base-excitation generated by a transient displacement field of a prescribed surface acoustic wave pulse and reports the critical rolling angle data for a set of polystyrene latex microparticles.

  3. Avoiding the parametric roll

    NASA Astrophysics Data System (ADS)

    Acomi, Nicoleta; Ancuţa, Cristian; Andrei, Cristian; Boştinǎ, Alina; Boştinǎ, Aurel

    2016-12-01

    Ships are mainly built to sail and transport cargo at sea. Environmental conditions and state of the sea are communicated to vessels through periodic weather forecasts. Despite officers being aware of the sea state, their sea time experience is a decisive factor when the vessel encounters severe environmental conditions. Another important factor is the loading condition of the vessel, which triggers different behaviour in similar marine environmental conditions. This paper aims to analyse the behaviour of a port container vessel in severe environmental conditions and to estimate the potential conditions of parametric roll resonance. Octopus software simulation is employed to simulate vessel motions under certain conditions of the sea, with possibility to analyse the behaviour of ships and the impact of high waves on ships due to specific wave encounter situations. The study should be regarded as a supporting tool during the decision making process.

  4. Manufacturing Demonstration Facility: Roll-to-Roll Processing

    SciTech Connect

    Datskos, Panos G; Joshi, Pooran C; List III, Frederick Alyious; Duty, Chad E; Armstrong, Beth L; Ivanov, Ilia N; Jacobs, Christopher B; Graham, David E; Moon, Ji Won

    2015-08-01

    This Manufacturing Demonstration Facility (MDF)e roll-to-roll processing effort described in this report provided an excellent opportunity to investigate a number of advanced manufacturing approaches to achieve a path for low cost devices and sensors. Critical to this effort is the ability to deposit thin films at low temperatures using nanomaterials derived from nanofermentation. The overarching goal of this project was to develop roll-to-roll manufacturing processes of thin film deposition on low-cost flexible substrates for electronics and sensor applications. This project utilized ORNL s unique Pulse Thermal Processing (PTP) technologies coupled with non-vacuum low temperature deposition techniques, ORNL s clean room facility, slot dye coating, drop casting, spin coating, screen printing and several other equipment including a Dimatix ink jet printer and a large-scale Kyocera ink jet printer. The roll-to-roll processing project had three main tasks: 1) develop and demonstrate zinc-Zn based opto-electronic sensors using low cost nanoparticulate structures manufactured in a related MDF Project using nanofermentation techniques, 2) evaluate the use of silver based conductive inks developed by project partner NovaCentrix for electronic device fabrication, and 3) demonstrate a suite of low cost printed sensors developed using non-vacuum deposition techniques which involved the integration of metal and semiconductor layers to establish a diverse sensor platform technology.

  5. Rolling Process Modeling Report: Finite-Element Prediction of Roll Separating Force and Rolling Defects

    SciTech Connect

    Soulami, Ayoub; Lavender, Curt A.; Paxton, Dean M.; Burkes, Douglas

    2014-04-23

    Pacific Northwest National Laboratory (PNNL) has been investigating manufacturing processes for the uranium-10% molybdenum (U-10Mo) alloy plate-type fuel for the U.S. high-performance research reactors. This work supports the Convert Program of the U.S. Department of Energy’s National Nuclear Security Administration (DOE/NNSA) Global Threat Reduction Initiative. This report documents modeling results of PNNL’s efforts to perform finite-element simulations to predict roll separating forces and rolling defects. Simulations were performed using a finite-element model developed using the commercial code LS-Dyna. Simulations of the hot rolling of U-10Mo coupons encapsulated in low-carbon steel have been conducted following two different schedules. Model predictions of the roll-separation force and roll-pack thicknesses at different stages of the rolling process were compared with experimental measurements. This report discusses various attributes of the rolled coupons revealed by the model (e.g., dog-boning and thickness non-uniformity).

  6. Body roll in swimming: a review.

    PubMed

    Psycharakis, Stelios G; Sanders, Ross H

    2010-02-01

    In this article, we present a critical review of the swimming literature on body roll, for the purposes of summarizing and highlighting existing knowledge, identifying the gaps and limitations, and stimulating further research. The main research findings can be summarized as follows: swimmers roll their shoulders significantly more than their hips; swimmers increase hip roll but maintain shoulder roll when fatigued; faster swimmers roll their shoulders less than slower swimmers during a 200-m swim; roll asymmetries, temporal differences in shoulder roll and hip roll, and shoulder roll side dominance exist in front crawl swimming, but there is no evidence to suggest that they affect swimming performance; and buoyancy contributes strongly to generating body roll in front crawl swimming. Based on and stimulated by current knowledge, future research should focus on the following areas: calculation of body roll for female swimmers and for backstroke swimming; differences in body roll between breathing and non-breathing cycles; causes of body roll asymmetries and their relation to motor laterality; body roll analysis across a wide range of velocities and swimming distances; exploration of the association between body roll and the magnitude and direction of propulsive/resistive forces developed during the stroke cycle; and the influence of kicking actions on the generation of body roll.

  7. Development of roll-to-roll hot embossing system with induction heater for micro fabrication.

    PubMed

    Yun, Dongwon; Son, Youngsu; Kyung, Jinho; Park, Heechang; Park, Chanhun; Lee, Sunghee; Kim, Byungin

    2012-01-01

    In this paper, a hot embossing heating roll with induction heater inside the roll is proposed. The induction heating coil is installed inside a roll that is used as a heating roll of a roll-to-roll (R2R) hot embossing apparatus. Using an inside installed heating coil gives the roll-to-roll hot embossing system a more even temperature distribution on the surface of the heating roll compared to that of previous systems, which used an electric wire for heating. This internal induction heating roll can keep the working environment much cleaner because there is no oil leakage compared to the oiled heating roll. This paper describes the principles and provides an analysis of this proposed system; some evaluation has also been performed for the system. A real R2R hot embossing heating roll system was fabricated and some experiments on micro-pattering have been performed. After that, evaluation has been performed on the results.

  8. 75 FR 64254 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products From Brazil; Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-19

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products From Brazil... order on certain hot-rolled, flat-rolled carbon quality steel products (hot-rolled steel) from Brazil. See Certain Hot- Rolled Flat-Rolled Carbon Quality Steel Products From Brazil: Preliminary Results...

  9. Fundamental phenomena governing heat transfer during rolling

    NASA Astrophysics Data System (ADS)

    Chen, W. C.; Samarasekera, I. V.; Hawbolt, E. B.

    1993-06-01

    To quantify the effect of roll chilling on the thermal history of a slab during hot rolling, tests were conducted at the Canada Center for Mineral and Energy Technology (CANMET) and at the University of British Columbia (UBC). In these tests, the surface and the interior temperatures of specimens were recorded during rolling using a data acquisition system. The corresponding heat-transfer coefficients in the roll bite were back-calculated by a trial-and-error method using a heat-transfer model. The heat-transfer coefficient was found to increase along the arc of contact and reach a maximum, followed by a decrease, until the exit of the roll bite. Its value was influenced by rolling parameters, such as percent reduction, rolling speed, rolling temperature, material type, etc. It was shown that the heat-transfer coefficient in the roll gap was strongly dependent on the roll pressure, and the effect of different variables on the interfacial heat-transfer coefficient can be related to their influence on pressure. At low mean roll pressure, such as in the case of rolling plain carbon steels at elevated temperature, the maximum heat-transfer coefficient in the roll bite was in the 25 to 35 kW/m2 °C range. As the roll pressure increased with lower rolling temperature and higher deformation resistance of stainless steel and microalloyed grades, the maximum heat-transfer coefficient reached a value of 620 kW/m2 °C. Obviously, the high pressure improved the contact between the roll and the slab surface, thereby reducing the resistance to heat flow. The mean roll-gap heat-transfer coefficient at the interface was shown to be linearly related to mean roll pressure. This finding is important because it permitted a determination of heat-transfer coefficients applicable to industrial rolling from pilot mill data. Thus, the thermal history of a slab during rough rolling was computed using a model in which the mean heat-transfer coefficient between the roll and the slab was

  10. Hot rolling of thick uranium molybdenum alloys

    DOEpatents

    DeMint, Amy L.; Gooch, Jack G.

    2015-11-17

    Disclosed herein are processes for hot rolling billets of uranium that have been alloyed with about ten weight percent molybdenum to produce cold-rollable sheets that are about one hundred mils thick. In certain embodiments, the billets have a thickness of about 7/8 inch or greater. Disclosed processes typically involve a rolling schedule that includes a light rolling pass and at least one medium rolling pass. Processes may also include reheating the rolling stock and using one or more heavy rolling passes, and may include an annealing step.

  11. Improvement of rolling 6 mm thin plates in plate rolling mill PT. Krakatau Posco

    NASA Astrophysics Data System (ADS)

    Pujiyanto, Hamdani

    2017-01-01

    A 6-mm thin plate is difficult to produce especially if the product requires wide size and high strength. Flatness is the main quality issue in rolling 6-mm plate using a 4-high reversing mill which use ±1100-mm work roll. Thus some methods are applied to overcome such issue in order to comply to customer quality requirement. Pre-rolling, rolling, and post-rolling conditions have to be considered comprehensively. Roll unit management will be the key factor before rolling condition. The roll unit itself has a significant impact on work roll crown wearness in relation with work roll intial crown and thermal crown. Work roll crown along with the modification of hydraulic gap control (HGC) could directly alter the flatness of the plate.

  12. Roll-to-Roll Nanoimprint Lithography Simulations for Flexible Substrates

    NASA Astrophysics Data System (ADS)

    Spann, Andrew; Jain, Akhilesh; Bonnecaze, Roger

    2015-11-01

    UV roll-to-roll nanoimprint lithography enables the patterning of features onto a flexible substrate for bendable electronics in a continuous process. One of the most important design goals in this process is to make the residual layer thickness of the photoresist in unpatterned regions as thin and uniform as possible. Another important goal is to minimize the imprint time to maximize throughput. We develop a multi-scale model to simulate the spreading of photoresist drops as the template is pressed against the substrate. We include the effect of capillary pressure on the bending of the substrate and show how this distorts uniformity in the residual thickness layer. Our simulation code is parallelized and can simulate the flow and merging of thousands of drops. We investigate the effect of substrate tension and the initial arrangement of drops on the residual layer thickness and imprint time. We find that for a given volume of photoresist, distributing that volume to more drops initially decreases the imprint time. We conclude with recommendations for scale-up and optimal operations of roll-to-roll nanoimprint lithography systems. The authors acknowledge the Texas Advanced Computing Center at The University of Texas at Austin for providing high performance computing resources.

  13. Climate Ready Estuaries Rolling Easements Primer

    EPA Pesticide Factsheets

    Rolling easements enable wetlands and beaches to migrate inland and allow society to avoid the costs and hazards of protecting low lands from rising sea levels. This document provides a primer on more than a dozen rolling easement approaches.

  14. One-zone rolling of composite materials

    NASA Astrophysics Data System (ADS)

    Kokhan, L. S.; Morozov, Yu. A.; Slavgorodskaya, Yu. B.

    2016-12-01

    The energy-force parameters of free rolling of a strip without its tension and rolling with one backward or forward creep zone in the deformation zone are compared. The limiting backward or forward tensions are determined, and the change in the linear sizes of a composite billet during deformation in a rolling mill is considered.

  15. Rolling Tachyon in Nonlocal Cosmology

    SciTech Connect

    Joukovskaya, L.

    2007-11-20

    Nonlocal cosmological models derived from String Field Theory are considered. A new method for constructing rolling tachyon solutions in the FRW metric in two field configuration is proposed and solutions of the Friedman equations with nonlocal operator are presented. The cosmological properties of these solutions are discussed.

  16. The Discovery of Rolling Circle Amplification and Rolling Circle Transcription.

    PubMed

    Mohsen, Michael G; Kool, Eric T

    2016-11-15

    Nucleic acid amplification is a hugely important technology for biology and medicine. While the polymerase chain reaction (PCR) has been highly useful and effective, its reliance on heating and cooling cycles places some constraints on its utility. For example, the heating step of PCR can destroy biological molecules under investigation and heat/cool cycles are not applicable in living systems. Thus, isothermal approaches to DNA and RNA amplification are under widespread study. Perhaps the simplest of these are the rolling circle approaches, including rolling circle amplification (RCA) and rolling circle transcription (RCT). In this strategy, a very small circular oligonucleotide (e.g., 25-100 nucleotides in length) acts as a template for a DNA or an RNA polymerase, producing long repeating product strands that serve as amplified copies of the circle sequence. Here we describe the early developments and studies involving circular oligonucleotides that ultimately led to the burgeoning rolling circle technologies currently under development. This Account starts with our studies on the design of circular oligonucleotides as novel DNA- and RNA-binding motifs. We describe how we developed chemical and biochemical strategies for synthesis of well-defined circular oligonucleotides having defined sequence and open (unpaired) structure, and we outline the unusual ways in which circular DNAs can interact with other nucleic acids. We proceed next to the discovery of DNA and RNA polymerase activity on these very small cyclic DNAs. DNA polymerase "rolling circle" activities were discovered concurrently in our laboratory and that of Andrew Fire. We describe the surprising efficiency of this process even on shockingly small circular DNAs, producing repeating DNAs thousands of nucleotides in length. RNA polymerase activity on circular oligonucleotides was first documented in our group in 1995; especially surprising in this case was the finding that the process occurs efficiently

  17. 76 FR 34101 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ... COMMISSION Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia Determinations... U.S.C. 1675(c)), that termination of the suspension agreement on hot- rolled flat-rolled carbon... determines that revocation of the countervailing duty order on hot-rolled flat-rolled carbon-quality...

  18. 75 FR 16504 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-01

    ... COMMISSION Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia AGENCY: United... countervailing duty order on certain hot-rolled flat-rolled carbon-quality steel products (``hot-rolled steel'') from Brazil, the antidumping duty orders on hot-rolled steel from Brazil and Japan, and the...

  19. 76 FR 22868 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-25

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil... certain hot-rolled flat-rolled carbon- quality steel products (HRS) from Brazil for the period January 1...: Background Since the issuance of Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From...

  20. 75 FR 42782 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... COMMISSION Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia AGENCY: United...-year reviews concerning the countervailing duty order on certain hot-rolled flat-rolled carbon-quality steel products (``hot-rolled steel'') from Brazil, the antidumping duty orders on hot-rolled steel...

  1. 75 FR 62566 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... COMMISSION Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia AGENCY: United... countervailing duty order on hot-rolled flat-rolled carbon-quality steel products (``hot-rolled steel'') from Brazil, the antidumping duty orders on hot-rolled steel from Brazil and Japan, and the...

  2. 75 FR 47263 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From the Russian Federation; Final...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-05

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From the Russian... expedited sunset review of the antidumping duty suspended investigation on certain hot-rolled flat-rolled... antidumping duty investigation of certain hot-rolled flat- rolled carbon-quality steel products...

  3. 75 FR 65453 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Flat Products From Brazil: Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-25

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Flat Products From Brazil... duty order on certain hot-rolled flat-rolled carbon quality steel flat products (hot-rolled steel) from Brazil. The review covers four producers/exporters of hot-rolled steel from Brazil, all...

  4. A rolling 3-UPU parallel mechanism

    NASA Astrophysics Data System (ADS)

    Miao, Zhihuai; Yao, Yan'an; Kong, Xianwen

    2013-12-01

    A novel rolling mechanism is proposed based on a 3-UPU parallel mechanism in this paper. The rolling mechanism is composed of two platforms connected by three UPU (universal-prismatic-universal) serial-chain type limbs. The degree-of-freedom of the mechanism is analyzed using screw theory. Gait analysis and stability analysis are presented in detail. Four rolling modes of the mechanism are discussed and simulated. The feasibility of the rolling mechanism is verified by means of a physical prototype. Finally, its terrain adaptability is enhanced through planning the rolling gaits.

  5. Roll Casting of Al-25%Si

    SciTech Connect

    Haga, Toshio; Harada, Hideto; Watari, Hisaki

    2011-05-04

    Strip casting of Al-25%Si strip was tried using an unequal diameter twin roll caster. The diameter of the lower roll (large roll) was 1000 mm and the diameter of the upper roll (small roll) was 250 mm. Roll material was mild steel. The sound strip could be cast at the speeds ranging from 8 m/min to 12 m/min. The strip did not stick to the roll without the parting material. The primary Si, which existed at centre area of the thickness direction, was larger than that which existed at other area. The size of the primary Si was smaller than 0.2 mm. Eutectic Si was smaller 5 {mu}m. The as-cast strip was ranging from 2 mm to 3 mm thick and its width was 100 mm. The as-cast strip could be hot rolled down to 1 mm. The hot rolled strip was cold rolled. The primary Si became smaller and the pore occurred around the primary Si after the rolling.

  6. Towards roll-to-roll manufacturing of polymer photonic devices

    NASA Astrophysics Data System (ADS)

    Subbaraman, Harish; Lin, Xiaohui; Ling, Tao; Guo, L. Jay; Chen, Ray T.

    2014-03-01

    Traditionally, polymer photonic devices are fabricated using clean-room processes such as photolithography, e-beam lithography, reactive ion etching (RIE) and lift-off methods etc, which leads to long fabrication time, low throughput and high cost. We have utilized a novel process for fabricating polymer photonic devices using a combination of imprinting and ink jet printing methods, which provides high throughput on a variety of rigid and flexible substrates with low cost. We discuss the manufacturing challenges that need to be overcome in order to realize true implementation of roll-to-roll manufacturing of flexible polymer photonic systems. Several metrology and instrumentation challenges involved such as availability of particulate-free high quality substrate, development and implementation of high-speed in-line and off-line inspection and diagnostic tools with adaptive control for patterned and unpatterned material films, development of reliable hardware, etc need to be addressed and overcome in order to realize a successful manufacturing process. Due to extreme resolution requirements compared to print media, the burden of software and hardware tools on the throughput also needs to be carefully determined. Moreover, the effect of web wander and variations in web speed need to accurately be determined in the design of the system hardware and software. In this paper, we show the realization of solutions for few challenges, and utilizing these solutions for developing a high-rate R2R dual stage ink-jet printer that can provide alignment accuracy of <10μm at a web speed of 5m/min. The development of a roll-to-roll manufacturing system for polymer photonic systems opens limitless possibilities for the deployment of high performance components in a variety of applications including communication, sensing, medicine, agriculture, energy, lighting etc.

  7. Rubber rolling over a sphere

    NASA Astrophysics Data System (ADS)

    Koiller, J.; Ehlers, K.

    2007-04-01

    “Rubber” coated bodies rolling over a surface satisfy a no-twist condition in addition to the no slip condition satisfied by “marble” coated bodies [1]. Rubber rolling has an interesting differential geometric appeal because the geodesic curvatures of the curves on the surfaces at corresponding points are equal. The associated distribution in the 5 dimensional configuration space has 2 3 5 growth (these distributions were first studied by Cartan; he showed that the maximal symmetries occurs for rubber rolling of spheres with 3:1 diameters ratio and materialize the exceptional group G 2). The 2 3 5 nonholonomic geometries are classified in a companion paper [2] via Cartan’s equivalence method [3]. Rubber rolling of a convex body over a sphere defines a generalized Chaplygin system [4 8] with SO(3) symmetry group, total space Q = SO(3) × S 2 and base S 2, that can be reduced to an almost Hamiltonian system in T* S 2 with a non-closed 2-form ωNH. In this paper we present some basic results on the sphere-sphere problem: a dynamically asymmetric but balanced sphere of radius b (unequal moments of inertia I j but with center of gravity at the geometric center), rubber rolling over another sphere of radius a. In this example ωNH is conformally symplectic [9]: the reduced system becomes Hamiltonian after a coordinate dependent change of time. In particular there is an invariant measure, whose density is the determinant of the reduced Legendre transform, to the power p = 1/2( b/a - 1). Using sphero-conical coordinates we verify the result by Borisov and Mamaev [10] that the system is integrable for p = -1/2 (ball over a plane). They have found another integrable case [11] corresponding to p = -3/2 (rolling ball with twice the radius of a fixed internal ball). Strikingly, a different set of sphero-conical coordinates separates the Hamiltonian in this case. No other integrable cases with different I j are known.

  8. Tribological Testing of Anti-Adhesive coatings for Cold Rolling Mill Rolls--Application to TiN-Coated Rolls

    SciTech Connect

    Ould, Choumad; Montmitonnet, Pierre; Gachon, Yves; Badiche, Xavier

    2011-05-04

    Roll life is a major issue in cold strip rolling. Roll wear may result either in too low roll roughness, bringing friction below the minimum requested for strip entrainment; or it may degrade strip surface quality. On the contrary, adhesive wear and transfer (''roll coating'', ''pick up'') may form a thick metallic deposits on the roll which increases friction excessively and degrades strip surface again [1]. The roll surface, with the help of a materials-adapted lubricant, must therefore possess anti-wear and anti-adhesive properties. Thus, High Speed Steeel (HSS) rolls show superior properties compared with standard Cr-steel rolls due to their high carbide surface coverage. Another way to improve wear and adhesion properties of surfaces is to apply hard metallic (hard-Cr) or ceramic coatings. Chromium is renowned for its excellent anti-wear and anti-adhesive properties and may serve as a reference. Here, as a first step towards alternative, optimised coatings, a PVD TiN coating has been deposited on tool steels, as previous attempts have proved TiN to be rather successful in cold rolling experiments [2,3]. Different tribological tests are reported here, giving insight in both anti-adhesive properties and fatigue life improvement.

  9. Rolling-Friction Robotic Gripper

    NASA Technical Reports Server (NTRS)

    Vranish, John M.

    1992-01-01

    Robotic gripper using rolling-friction fingers closes in on object with interface designed to mate with rollers somewhat misaligned initially, aligns object with respect to itself, then holds object securely in uniquely determined position and orientation. Operation of gripper causes minimal wear and burring of gripper and object. Exerts minimal friction forces on object when grasping and releasing. Releases object easily and reliably even when side forces and torques are between itself and object.

  10. Rolling Mill Hill, Nashville, TN

    EPA Pesticide Factsheets

    Rolling Mill Hill was the home to Nashville General Hospital from 1890 to the 1990s and encompassed several buildings and structures. These existing buildings of historical significance were re-used in the form of apartments. The original Trolley Barns on the site are now artists’ lofts and are home to several companies and non-profit offices. Nance Place, which entails additional buildings built on-site, is a Tax Credit Workforce Housing Development and is Platinum LEED certified.

  11. Roll formed pan solar module

    SciTech Connect

    Jester, T.L.; Bottenberg, W.R.; Gay, C.F.; Yerkes, J.W.

    1984-02-21

    A solar module comprising a solar cell string laminated between layers of pottant material and a transparent superstrate and a steel substrate. The steel substrate is roll formed to provide stiffening flanges on its edges while simultaneously forming a pan-shaped structure to hold other portions of the laminate in position during the laminating process. An improved terminal provides high voltage protection and improved mechanical strength. A conduit element provides protected raceways for external wires connected to module terminals.

  12. Rolling Contact Fatigue of Ceramics

    SciTech Connect

    Wereszczak, Andrew A; Wang, W.; Wang, Y.; Hadfield, M.; Kanematsu, W.; Kirkland, Timothy Philip; Jadaan, Osama M.

    2006-09-01

    High hardness, low coefficient of thermal expansion and high temperature capability are properties also suited to rolling element materials. Silicon nitride (Si{sub 3}N{sub 4}) has been found to have a good combination of properties suitable for these applications. However, much is still not known about rolling contact fatigue (RCF) behavior, which is fundamental information to assess the lifetime of the material. Additionally, there are several test techniques that are employed internationally whose measured RCF performances are often irreconcilable. Due to the lack of such information, some concern for the reliability of ceramic bearings still remains. This report surveys a variety of topics pertaining to RCF. Surface defects (cracks) in Si{sub 3}N{sub 4} and their propagation during RCF are discussed. Five methods to measure RCF are then briefly overviewed. Spalling, delamination, and rolling contact wear are discussed. Lastly, methods to destructively (e.g., C-sphere flexure strength testing) and non-destructively identify potential RCF-limiting flaws in Si{sub 3}N{sub 4} balls are described.

  13. A Semianalytic Model of Leukocyte Rolling

    PubMed Central

    Krasik, Ellen F.; Hammer, Daniel A.

    2004-01-01

    Rolling allows leukocytes to maintain adhesion to vascular endothelium and to molecularly coated surfaces in flow chambers. Using insights from adhesive dynamics, a computational method for simulating leukocyte rolling and firm adhesion, we have developed a semianalytic model for the steady-state rolling of a leukocyte. After formation in a force-free region of the contact zone, receptor-ligand bonds are transported into the trailing edge of the contact zone. Rolling velocity results from a balance of the convective flux of bonds and the rate of dissociation at the back edge of the contact zone. We compare the model's results to that of adhesive dynamics and to experimental data on the rolling of leukocytes, with good agreement. We calculate the dependence of rolling velocity on shear rate, intrinsic forward and reverse reaction rates, bond stiffness, and reactive compliance, and use the model to calculate a state diagram relating molecular parameters and the dynamic state of adhesion. A dimensionless form of the analytic model permits exploration of the parameters that control rolling. The chemical affinity of a receptor-ligand pair does not uniquely determine rolling velocity. We elucidate a fundamental relationship between off-rate, ligand density, and reactive compliance at the transition between firm and rolling adhesion. The model provides a rapid method for screening system parameters for the potential to mediate rolling. PMID:15315955

  14. How rolling forecasting facilitates dynamic, agile planning.

    PubMed

    Miller, Debra; Allen, Michael; Schnittger, Stephanie; Hackman, Theresa

    2013-11-01

    Rolling forecasting may be used to replace or supplement the annual budget process. The rolling forecast typically builds on the organization's strategic financial plan, focusing on the first three years of plan projections and comparing the strategic financial plan assumptions with the organization's expected trajectory. Leaders can then identify and respond to gaps between the rolling forecast and the strategic financial plan on an ongoing basis.

  15. METHOD OF HOT ROLLING URANIUM METAL

    DOEpatents

    Kaufmann, A.R.

    1959-03-10

    A method is given for quickly and efficiently hot rolling uranium metal in the upper part of the alpha phase temperature region to obtain sound bars and sheets possessing a good surface finish. The uranium metal billet is heated to a temperature in the range of 1000 deg F to 1220 deg F by immersion iii a molten lead bath. The heated billet is then passed through the rolls. The temperature is restored to the desired range between successive passes through the rolls, and the rolls are turned down approximately 0.050 inch between successive passes.

  16. Spray Rolling Aluminum Strip for Transportation Applications

    SciTech Connect

    Kevin M. McHugh; Y. Lin; Y. Zhou; E. J. Lavernia; J.-P. Delplanque; S. B. Johnson

    2005-02-01

    Spray rolling is a novel strip casting technology in which molten aluminum alloy is atomized and deposited into the roll gap of mill rolls to produce aluminum strip. A combined experimental/modeling approach has been followed in developing this technology with active participation from industry. The feasibility of this technology has been demonstrated at the laboratory scale and it is currently being scaled-up. This paper provides an overview of the process and compares the microstructure and properties of spray-rolled 2124 aluminum alloy with commercial ingot-processed material

  17. Effect of temper rolling on final shape defects in a V-section roll forming process

    NASA Astrophysics Data System (ADS)

    Abvabi, Akbar; Rolfe, Bernard; Hodgson, Peter D.; Weiss, Matthias

    2013-12-01

    Roll forming is a continuous process in which a flat strip is shaped to the desired profile by sequential bending in a series of roll stands. Because of the large variety of applications of roll forming in the industry, Finite Element Analysis (FEA) is increasingly utilized for roll forming process design. Bending is the dominant deformation mode in roll forming. Sheet materials used in this process are generally temper rolled, roller- or tension- leveled. These processes introduce residual stresses into the material, and recent studies have shown that those affect the material behavior in bending. In this study a numerical model of the temper rolling (skin passing) process was used to determine a residual stress distribution in a dual phase, DP780, steel strip. A 5-stand roll forming process for the forming of a V-section was modeled, and the effect of various thickness reduction levels in the temper rolling process on the final shape defects was analyzed. The results show that a small thickness reduction in the temper rolling process decreases the maximum bow height but the final springback angle increases. It is also shown that reasonable model accuracy can be achieved by including the residual stress information due to temper rolling as initial condition in the numerical modeling of a roll forming process.

  18. Rolling-cuff flexible bellows

    DOEpatents

    Lambert, D.R.

    1982-09-27

    A flexible connector apparatus used to join two stiff non-deformable members, such as piping, is described. The apparatus is provided with one or more flexible sections or assemblies each utilizing a bellows of a rolling cuff type connected between two ridge members, with the bellows being supported by a back-up ring, such that only the curved end sections of the bellows are unsupported. Thus, the bellows can be considered as being of a tube-shaped configuration and thus have high pressure resistance. The components of the flexible apparatus are sealed or welded one to another such that it is fluid tight.

  19. 75 FR 19369 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products from Brazil: Preliminary Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-14

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products from Brazil... conducting an administrative review of the antidumping duty order on certain hot-rolled flat-rolled carbon quality steel products (hot-rolled steel) from Brazil. The review covers Usinas Siderurgicas de...

  20. 75 FR 43931 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products from Brazil: Preliminary Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-27

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products from Brazil... a sunset review of the countervailing duty (``CVD'') order on certain hot-rolled flat-rolled carbon... Department initiated the second sunset review of the countervailing duty order on hot-rolled...

  1. 77 FR 32513 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From the Russian Federation; Preliminary...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-01

    ... International Trade Administration Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From the Russian... of the Administrative Review of the Suspension Agreement on Hot-Rolled Flat-Rolled Carbon-Quality... administrative review of the Agreement Suspending the Antidumping Duty Investigation of Hot-Rolled...

  2. 76 FR 62894 - Following Procedures When Going Between Rolling Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... Federal Railroad Administration Following Procedures When Going Between Rolling Equipment AGENCY: Federal... of following procedures when going ] between rolling equipment. This safety advisory contains various... who, in the course of their work, place themselves between rolling equipment. The railroad...

  3. Rolling Friction on a Wheeled Laboratory Cart

    DTIC Science & Technology

    2012-01-01

    by gravity, and a vehicle (such as a car or bicycle ) accelerating along a level road is driven by a motor or by pedalling. In such cases, static...continuously roll. Consider a cart of mass m that is free rolling up an incline, as sketched in figure 1. The total frictional force f on the cart

  4. School Roll Forecasting Methods: A Review.

    ERIC Educational Resources Information Center

    Simpson, Stephen

    1987-01-01

    A review of the literature concerning local school roll forecasting describes the theoretical model common to most local education agency (LEA) forecasts, identifies a variety of issues relevant to this area of LEA planning, and suggests some opportunities for improvement in LEA school roll forecasting. (Author/CB)

  5. 33 CFR 159.107 - Rolling test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Rolling test. 159.107 Section 159.107 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.107 Rolling test. (a) The device,...

  6. Numerical analysis of Swiss roll metamaterials.

    PubMed

    Demetriadou, A; Pendry, J B

    2009-08-12

    A Swiss roll metamaterial is a resonant magnetic medium, with a negative magnetic permeability for a range of frequencies, due to its self-inductance and self-capacitance components. In this paper, we discuss the band structure, S-parameters and effective electromagnetic parameters of Swiss roll metamaterials, with both analytical and numerical results, which show an exceptional convergence.

  7. Rolling maneuver load alleviation using active controls

    NASA Technical Reports Server (NTRS)

    Woods-Vedeler, Jessica A.; Pototzky, Anthony S.

    1992-01-01

    Rolling Maneuver Load Alleviation (RMLA) was demonstrated on the Active Flexible Wing (AFW) wind tunnel model in the LaRC Transonic Dynamics Tunnel. The design objective was to develop a systematic approach for developing active control laws to alleviate wing incremental loads during roll maneuvers. Using linear load models for the AFW wind-tunnel model which were based on experimental measurements, two RMLA control laws were developed based on a single-degree-of-freedom roll model. The RMLA control laws utilized actuation of outboard control surface pairs to counteract incremental loads generated during rolling maneuvers and roll performance. To evaluate the RMLA control laws, roll maneuvers were performed in the wind tunnel at dynamic pressures of 150, 200, and 250 psf and Mach numbers of .33, .38, and .44, respectively. Loads obtained during these maneuvers were compared to baseline maneuver loads. For both RMLA controllers, the incremental torsion moments were reduced by up to 60 percent at all dynamic pressures and performance times. Results for bending moment load reductions during roll maneuvers varied. In addition, in a multiple function test, RMLA and flutter suppression system control laws were operated simultaneously during roll maneuvers at dynamic pressures 11 percent above the open-loop flutter dynamic pressure.

  8. Roll-forming tubes to header plates

    NASA Technical Reports Server (NTRS)

    Kramer, K.

    1976-01-01

    Technique has been developed for attaching and sealing tubes to header plates using a unique roll-forming tool. Technique is useful for attaching small tubes which are difficult to roll into conventional grooves in header plate tube holes, and for attaching when welding, brazing, or soldering is not desirable.

  9. Lubrication of rolling-element bearings

    NASA Technical Reports Server (NTRS)

    Parker, R. J.

    1980-01-01

    The lubrication of rolling element bearings is surveyed. Emphasis is on the critical design aspects related to speed, temperature, and ambient pressure environment. Types of lubrication including grease, jets, mist, wick, and through the race are discussed. The historical development, present state of technology, and the future problems of rolling element bearing lubrication are discussed.

  10. Advances in roll-to-roll imprint lithography for display applications

    NASA Astrophysics Data System (ADS)

    Jeans, Albert; Almanza-Workman, Marcia; Cobene, Robert; Elder, Richard; Garcia, Robert; Gomez-Pancorbo, Fernando; Jackson, Warren; Jam, Mehrban; Kim, Han-Jun; Kwon, Ohseung; Luo, Hao; Maltabes, John; Mei, Ping; Perlov, Craig; Smith, Mark; Taussig, Carl; Jeffrey, Frank; Braymen, Steve; Hauschildt, Jason; Junge, Kelly; Larson, Don; Stieler, Dan

    2010-03-01

    A solution to the problems of roll-to-roll lithography on flexible substrates is presented. We have developed a roll-toroll imprint lithography technique to fabricate active matrix transistor backplanes on flexible webs of polyimide that have a blanket material stack of metals, dielectrics, and semiconductors. Imprint lithography produces a multi-level 3- dimensional mask that is then successively etched to pattern the underlying layers into the desired structures. This process, Self-Aligned Imprint Lithography (SAIL), solves the layer-to-layer alignment problem because all masking levels are created with one imprint step. The processes and equipment required for complete roll-to-roll SAIL fabrication will be described. Emphasis will be placed on the advances in the roll-to-roll imprint process which have enabled us to produce working transistor arrays.

  11. Roll-to-Roll Atomic Layer Deposition for Ultrabarriers

    NASA Astrophysics Data System (ADS)

    Yersak, Alexander

    Atomic layer deposition (ALD) is a bottom-up, gas phase, thin film deposition technique based on sequential, self-limiting binary surface reactions. The precise sub-nanometer film thickness control and conformal nature of this process have led to various commercial applications of ALD. However, ALD films are most commonly deposited in batch processes at low pressures, which raises throughput and/or cost concerns for many otherwise promising applications. This problem can be solved by spatial ALD (S-ALD) which is a version of the ALD technique where the precursors are separated in space rather than time. We have demonstrated the first atmospheric pressure roll-to-roll (R2R) ALD web coating system. A thickness uniformity of +/-2% was achieved across the web. ALD cycle times as low as 76 ms were demonstrated with a web speed of 1 m/s and a vertical gap height of 0.5 mm. Extrinsic defects in the ALD films were investigated, and a predictive cluster model was proposed, and was demonstrated with a residual (i.e. difference between the actual defect counts and those predicted by the cluster model) of <10%. A R2R ALD web coating tool with molecular layer deposition (MLD) capabilities was investigated and achieved a defect density <10 /cm2. A hyperbaric corrosion chamber with in situ monitoring of film thickness was demonstrated with the ability to characterize R2R ALD films using water dissolution as a metric. ALD SiO2 films were determined to be dissolution-predictable with a predicted dissolution rate of 3.7 nm/year at physiological temperatures. ALD TiO2 films were observed with no measurable dissolution in 150 °C water over the measurement period of 12 days.

  12. 76 FR 35400 - Continuation of Suspended Antidumping Duty Investigation on Certain Hot-Rolled Flat-Rolled Carbon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-17

    ... International Trade Administration Continuation of Suspended Antidumping Duty Investigation on Certain Hot...'') that termination of the suspended antidumping duty investigation on certain hot-rolled flat-rolled carbon quality steel products (``hot- rolled steel'') from the Russian Federation (``Russia'')...

  13. Roll Casting of Aluminum Alloy Clad Strip

    SciTech Connect

    Nakamura, R.; Tsuge, H.; Haga, T.; Watari, H.; Kumai, S.

    2011-01-17

    Casting of aluminum alloy three layers of clad strip was tried using the two sets of twin roll casters, and effects of the casting parameters on the cladding conditions were investigated. One twin roll caster was mounted on the other twin roll caster. Base strip was 8079 aluminum alloy and overlay strips were 6022 aluminum alloy. Effects of roll-load of upper and lower casters and melt temperature of the lower caster were investigated. When the roll-load of the upper and lower caster was large enough, the overlay strip could be solidified and be connected. The overlay strip could be connected when the melt of the overlay strip cast by the lower caster was low enough. Sound three layers of clad strip could be cast by proper conditions.

  14. Aerodynamics of a rolling airframe missile

    NASA Astrophysics Data System (ADS)

    Tisserand, L. E.

    1981-05-01

    For guidance-related reasons, there is considerable interest in rolling missiles having single-plane steering capability. To aid the aerodynamic design of these airframes, a unique investigation into the aerodynamics of a rolling, steering missile has been carried out. It represents the first known attempt to measure in a wind tunnel the aerodynamic forces and moments that act on a spinning body-canard-tail configuration that exercises canard steering in phase with body roll position. Measurements were made with the model spinning at steady-state roll rates ranging from 15 to 40 Hz over an angle-of-attack range up to about 16 deg. This short, exploratory investigation has demonstrated that a better understanding and a more complete definition of the aerodynamics of rolling, steering vehicles can be developed by way of simulative wind-tunnel testing.

  15. Automated Procedure for Roll Pass Design

    NASA Astrophysics Data System (ADS)

    Lambiase, F.; Langella, A.

    2009-04-01

    The aim of this work has been to develop an automatic roll pass design method, capable of minimizing the number of roll passes. The adoption of artificial intelligence technologies, particularly expert systems, and a hybrid model for the surface profile evaluation of rolled bars, has allowed us to model the search for the minimal sequence with a tree path search. This approach permitted a geometrical optimization of roll passes while allowing automation of the roll pass design process. Moreover, the heuristic nature of the inferential engine contributes a great deal toward reducing search time, thus allowing such a system to be employed for industrial purposes. Finally, this new approach was compared with other recently developed automatic systems to validate and measure possible improvements among them.

  16. Rolling Contact Force Energy Reconstruction

    NASA Astrophysics Data System (ADS)

    BRACCIALI, A.; CASCINI, G.

    2000-09-01

    Knowledge of the forces at the wheel-rail contact is fundamental to estimate the consequences in terms of noise and vibration. The traditional use of strain gauges mounted on the wheel web and axle is not capable of determining the high-frequency content of the contact force. Measurements made on the rail are characterized by the spatial variability of input-output transfer functions which makes it difficult to estimate the contact force by simple inversion of the point frequency response function. In this study the problem of rolling contact force reconstruction has been approached through the following steps: (i) the track has been characterized precisely for a finite length by the analysis of the time series of several impacts supplied with an instrumented hammer by using an ARMAX model that proved to be capable of modelling the vertical dynamics of the rail up to 5 kHz; (ii) the response of the rail has been simulated with a random force acting on the system, and the variability of the transfer function has been taken into account by distributing the force on adjacent elements; (iii) the simulated response has been compared with the rail acceleration measured for the passage of several trains; (iv) the wheel-rail contact force has been estimated with a closed-loop algorithm. It has thus been possible to reconstruct the13octave power spectrum of contact forces with a simple and stable iterative procedure. Forces reconstructed from different sensors were found to be practically the same for a given wheel; forces from nominally similar wheels are statistically examined and partial results of comparisons made on different rolling stock are shown.

  17. Inflation with a constant rate of roll

    SciTech Connect

    Motohashi, Hayato; Starobinsky, Alexei A.; Yokoyama, Jun'ichi E-mail: alstar@landau.ac.ru

    2015-09-01

    We consider an inflationary scenario where the rate of inflaton roll defined by {sup ··}φ/H φ-dot remains constant. The rate of roll is small for slow-roll inflation, while a generic rate of roll leads to the interesting case of 'constant-roll' inflation. We find a general exact solution for the inflaton potential required for such inflaton behaviour. In this model, due to non-slow evolution of background, the would-be decaying mode of linear scalar (curvature) perturbations may not be neglected. It can even grow for some values of the model parameter, while the other mode always remains constant. However, this always occurs for unstable solutions which are not attractors for the given potential. The most interesting particular cases of constant-roll inflation remaining viable with the most recent observational data are quadratic hilltop inflation (with cutoff) and natural inflation (with an additional negative cosmological constant). In these cases even-order slow-roll parameters approach non-negligible constants while the odd ones are asymptotically vanishing in the quasi-de Sitter regime.

  18. Inflation with a constant rate of roll

    NASA Astrophysics Data System (ADS)

    Motohashi, Hayato; Starobinsky, Alexei A.; Yokoyama, Jun'ichi

    2015-09-01

    We consider an inflationary scenario where the rate of inflaton roll defined by ̈phi/H dot phi remains constant. The rate of roll is small for slow-roll inflation, while a generic rate of roll leads to the interesting case of 'constant-roll' inflation. We find a general exact solution for the inflaton potential required for such inflaton behaviour. In this model, due to non-slow evolution of background, the would-be decaying mode of linear scalar (curvature) perturbations may not be neglected. It can even grow for some values of the model parameter, while the other mode always remains constant. However, this always occurs for unstable solutions which are not attractors for the given potential. The most interesting particular cases of constant-roll inflation remaining viable with the most recent observational data are quadratic hilltop inflation (with cutoff) and natural inflation (with an additional negative cosmological constant). In these cases even-order slow-roll parameters approach non-negligible constants while the odd ones are asymptotically vanishing in the quasi-de Sitter regime.

  19. 'Slings' enable neutrophil rolling at high shear.

    PubMed

    Sundd, Prithu; Gutierrez, Edgar; Koltsova, Ekaterina K; Kuwano, Yoshihiro; Fukuda, Satoru; Pospieszalska, Maria K; Groisman, Alex; Ley, Klaus

    2012-08-16

    Most leukocytes can roll along the walls of venules at low shear stress (1 dyn cm−2), but neutrophils have the ability to roll at tenfold higher shear stress in microvessels in vivo. The mechanisms involved in this shear-resistant rolling are known to involve cell flattening and pulling of long membrane tethers at the rear. Here we show that these long tethers do not retract as postulated, but instead persist and appear as 'slings' at the front of rolling cells. We demonstrate slings in a model of acute inflammation in vivo and on P-selectin in vitro, where P-selectin-glycoprotein-ligand-1 (PSGL-1) is found in discrete sticky patches whereas LFA-1 is expressed over the entire length on slings. As neutrophils roll forward, slings wrap around the rolling cells and undergo a step-wise peeling from the P-selectin substrate enabled by the failure of PSGL-1 patches under hydrodynamic forces. The 'step-wise peeling of slings' is distinct from the 'pulling of tethers' reported previously. Each sling effectively lays out a cell-autonomous adhesive substrate in front of neutrophils rolling at high shear stress during inflammation.

  20. Signal and power roll ring testing update

    NASA Technical Reports Server (NTRS)

    Smith, Dennis W.

    1989-01-01

    The development of the roll ring as a long-life, low-torque alternative to the slip ring is discussed. A roll ring consists of one or more circular flexures captured by their own spring force in the annular space between two concentric conductors or contact rings. The advantages of roll rings over other types of electrical transfer devices are: extremely low drag torque, high transfer efficiencies in high-power configurations, extremely low wear debris generation, long life, and low weight for high-power applications.

  1. Roll paper pilot. [mathematical model for predicting pilot rating of aircraft in roll task

    NASA Technical Reports Server (NTRS)

    Naylor, F. R.; Dillow, J. D.; Hannen, R. A.

    1973-01-01

    A mathematical model for predicting the pilot rating of an aircraft in a roll task is described. The model includes: (1) the lateral-directional aircraft equations of motion; (2) a stochastic gust model; (3) a pilot model with two free parameters; and (4) a pilot rating expression that is a function of rms roll angle and the pilot lead time constant. The pilot gain and lead time constant are selected to minimize the pilot rating expression. The pilot parameters are then adjusted to provide a 20% stability margin and the adjusted pilot parameters are used to compute a roll paper pilot rating of the aircraft/gust configuration. The roll paper pilot rating was computed for 25 aircraft/gust configurations. A range of actual ratings from 2 to 9 were encountered and the roll paper pilot ratings agree quite well with the actual ratings. In addition there is good correlation between predicted and measured rms roll angle.

  2. Why Low Bounce Balls Exhibit High Rolling Resistance

    ERIC Educational Resources Information Center

    Cross, Rod

    2015-01-01

    A simple experiment is described to measure the coefficient of rolling friction for a low bounce ball rolling on a horizontal surface. As observed previously by others, the coefficient increased with rolling speed. The energy loss due to rolling friction can be explained in terms of the measured coefficient of restitution for the ball, meaning…

  3. Moesin regulates neutrophil rolling velocity in vivo.

    PubMed

    Matsumoto, Masanori; Hirata, Takako

    2016-01-01

    During inflammation, the selectin-induced slow rolling of neutrophils on venules cooperates with chemokine signaling to mediate neutrophil recruitment into tissues. Previous studies identified P-selectin glycoprotein ligand-1 (PSGL-1) and CD44 as E-selectin ligands that activate integrins to induce slow rolling. We show here that in TNF-α-treated cremaster muscle venules, slow leukocyte rolling was impaired in mice deficient in moesin, a member of the ezrin-radixin-moesin (ERM) family. Accordingly, neutrophil recruitment in a peritonitis model was decreased in moesin-deficient mice when chemokine signaling was blocked with pertussis toxin. These results suggest that moesin contributes to the slow rolling and subsequent recruitment of neutrophils during inflammation.

  4. Mathematical modeling of deformation during hot rolling

    SciTech Connect

    Jin, D.; Stachowiak, R.G.; Samarasekera, I.V.; Brimacombe, J.K.

    1994-12-31

    The deformation that occurs in the roll bite during the hot rolling of steel, particularly the strain-rate and strain distribution, has been mathematically modeled using finite-element analysis. In this paper three different finite-element models are compared with one another and with industrial measurements. The first model is an Eulerian analysis based on the flow formulation method, while the second utilizes an Updated Lagrangian approach. The third model is based on a commercially available program DEFORM which also utilizes a Lagrangian reference frame. Model predictions of strain and strain-rate distribution, particularly near the surface of the slab, are strongly influenced by the treatment of friction at the boundary and the magnitude of the friction coefficient or shear factor. Roll forces predicted by the model have been compared with industrial rolling loads from a seven-stand hot-strip mill.

  5. Roll Damping Characterisation Program: User Guide

    DTIC Science & Technology

    2014-06-01

    sallying test. The Defence Science and Technology Organisation (DSTO) have developed a software-based tool called the Roll Damping Characterisation...Murray Riding Maritime Division Murray obtained a Bachelor of Science (Honours) Degree from the

  6. Next-Generation Space Ambitions Keep Rolling

    NASA Video Gallery

    As space shuttle Atlantis rolled to its new home at the Kennedy Space Center Visitor Complex earlier this month, NASA and its commercial crew partners reflected on the Space Shuttle Program's treme...

  7. Roll measurement of Tevatron dipoles and quadrupoles

    SciTech Connect

    Volk, J.T.; Elementi, L.; Gollwitzer, K.; Jostlein, H.; Nobrega, F.; Shiltsev, V.; Stefanski, R.

    2006-09-01

    In 2003 a simple digital level system was developed to allow for rapid roll measurements of all dipoles and quadrupoles in the Tevatron. The system uses a Mitutoyo digital level and a PC running MS WINDOWS XP and LAB VIEW to acquire data on the upstream and downstream roll of each magnet. The system is sufficiently simple that all 1,000 magnets in the Tevatron can be measured in less than 3 days. The data can be quickly processed allowing for correction of rolled magnets by the Fermilab alignment group. Data will be presented showing the state of the Tevatron in 2003 and the changes in rolls as measured in each shutdown since then.

  8. 49 CFR 393.134 - What are the rules for securing roll-on/roll-off or hook lift containers?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false What are the rules for securing roll-on/roll-off... Shifting and Falling Cargo Specific Securement Requirements by Commodity Type § 393.134 What are the rules for securing roll-on/roll-off or hook lift containers? (a) Applicability. The rules in this...

  9. Plasmid Rolling-Circle Replication.

    PubMed

    Ruiz-Masó, J A; MachóN, C; Bordanaba-Ruiseco, L; Espinosa, M; Coll, M; Del Solar, G

    2015-02-01

    Plasmids are DNA entities that undergo controlled replication independent of the chromosomal DNA, a crucial step that guarantees the prevalence of the plasmid in its host. DNA replication has to cope with the incapacity of the DNA polymerases to start de novo DNA synthesis, and different replication mechanisms offer diverse solutions to this problem. Rolling-circle replication (RCR) is a mechanism adopted by certain plasmids, among other genetic elements, that represents one of the simplest initiation strategies, that is, the nicking by a replication initiator protein on one parental strand to generate the primer for leading-strand initiation and a single priming site for lagging-strand synthesis. All RCR plasmid genomes consist of a number of basic elements: leading strand initiation and control, lagging strand origin, phenotypic determinants, and mobilization, generally in that order of frequency. RCR has been mainly characterized in Gram-positive bacterial plasmids, although it has also been described in Gram-negative bacterial or archaeal plasmids. Here we aim to provide an overview of the RCR plasmids' lifestyle, with emphasis on their characteristic traits, promiscuity, stability, utility as vectors, etc. While RCR is one of the best-characterized plasmid replication mechanisms, there are still many questions left unanswered, which will be pointed out along the way in this review.

  10. Strip edge cracking simulation in cold rolling

    NASA Astrophysics Data System (ADS)

    Hubert, C.; Dubar, L.; Dubar, M.; Dubois, A.

    2011-01-01

    This research work focuses on a specific defect which occurs during cold rolling of steel strips: edge-serration. Investigations on the industrial processes have led to the conclusion that this defect is the result of the edge-trimming and cold rolling sequences. The aim of this research work is to analyze the effect of the cutting process and the cold rolling on cracks occurrence, especially on strip edges. This study is performed using an experimental testing stand called Upsetting Rolling Test (URT). It allows to reproduce cold rolling contact parameters such as forward slip, reduction ratio and friction coefficients. Specimens sampled near trimmed industrial strip edges are deformed using the URT stand. Two sets of specimens with different stress states, obtained by annealing, are submitted to two reduction passes with extreme forward slips. Scanning electron microscopy observations added to 3D optical surface profiler topographies show that on one hand, forward slip has a major effect on cracks opening. On the other hand, cracks opening decreases according to high roll strip speed gradient. Concerning the heat-treated specimens, no crack appeared after all reduction passes, showing a large influence of the cutting process and consequently of the local stress state in the vicinity of the burnish and fracture regions.

  11. Ultra slow-roll G inflation

    NASA Astrophysics Data System (ADS)

    Hirano, Shin'ichi; Kobayashi, Tsutomu; Yokoyama, Shuichiro

    2016-11-01

    The conventional slow-roll approximation is broken in the so-called "ultra slow-roll" models of inflation, for which the inflaton potential is exactly (or extremely) flat. The interesting nature of (canonical) ultra slow-roll inflation is that the curvature perturbation grows on superhorizon scales, but has a scale-invariant power spectrum. We study the ultra slow-roll inflationary dynamics in the presence of noncanonical kinetic terms of the scalar field, namely ultra slow-roll G inflation. We compute the evolution of the curvature perturbation and show that the primordial power spectrum follows a broken power law with an oscillation feature. It is demonstrated that this could explain the lack of large-scale power in the cosmic microwave background temperature anisotropies. We also point out that the violation of the null energy condition is prohibited in ultra slow-roll G inflation, and hence a blue tensor tilt is impossible as long as inflation is driven by the potential. This statement is, however, not true if the energy density is dominated by the kinetic energy of the scalar field.

  12. Strip edge cracking simulation in cold rolling

    SciTech Connect

    Hubert, C.; Dubar, L.; Dubar, M.; Dubois, A.

    2011-01-17

    This research work focuses on a specific defect which occurs during cold rolling of steel strips: edge-serration. Investigations on the industrial processes have led to the conclusion that this defect is the result of the edge-trimming and cold rolling sequences. The aim of this research work is to analyze the effect of the cutting process and the cold rolling on cracks occurrence, especially on strip edges.This study is performed using an experimental testing stand called Upsetting Rolling Test (URT). It allows to reproduce cold rolling contact parameters such as forward slip, reduction ratio and friction coefficients. Specimens sampled near trimmed industrial strip edges are deformed using the URT stand. Two sets of specimens with different stress states, obtained by annealing, are submitted to two reduction passes with extreme forward slips.Scanning electron microscopy observations added to 3D optical surface profiler topographies show that on one hand, forward slip has a major effect on cracks opening. On the other hand, cracks opening decreases according to high roll strip speed gradient. Concerning the heat-treated specimens, no crack appeared after all reduction passes, showing a large influence of the cutting process and consequently of the local stress state in the vicinity of the burnish and fracture regions.

  13. Microalloyed HSLA (High Strength Low Alloy) Steels: Proceedings of Microalloying 󈨜 Held in Conjunction with the 1988 World Materials Congress, Chicago, Illinois, USA, 24-30 September 1988

    DTIC Science & Technology

    1988-01-01

    Baixa (27) POSCO Steel Products. Pohang Iron and Liga e Alta Resistencia (acos BLAR) com Niobio. Steel Company Ltd. Conpany publication. Siderurgia...R.C.. Perspectivas Tecnologicas Chapas Grossas de Alta Resistencia Originadas para a Ind6stria Sideriirgica Brasileira. do Lingotamento Continuo

  14. 75 FR 64246 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Correction to Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-19

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil... published a notice of antidumping duty order for certain hot-rolled flat-rolled carbon-quality steel products from Brazil. See Antidumping Duty Order: Certain Hot-Rolled Flat-Rolled Carbon-Quality...

  15. 77 FR 72820 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From the Russian Federation; 2010-2011...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-06

    ... International Trade Administration Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From the Russian... Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products from the Russian Federation (``the Agreement'') for the period July 1, 2010 through June 30, 2011. See Hot-Rolled Flat-Rolled ] Carbon-Quality...

  16. 75 FR 32160 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products from Brazil: Extension of Time Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-07

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products from Brazil... certain hot-rolled flat- rolled carbon-quality steel products from Brazil. See Agreement Suspending the Countervailing Duty Investigation on Hot-Rolled Flat- Rolled Carbon-Quality Steel From Brazil; Termination...

  17. 75 FR 75455 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Final Results of Full...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-03

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil... certain hot-rolled flat-rolled carbon-quality steel products (hot-rolled steel) from Brazil, pursuant to.../COSIPA) \\2\\ and Companhia Siderurgica Nacional (CSN), producers of hot-rolled steel, and the...

  18. 75 FR 47541 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products from Brazil and Japan: Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-06

    ... International Trade Administration Hot-Rolled Flat-Rolled Carbon-Quality Steel Products from Brazil and Japan... Commerce (the Department) initiated sunset reviews of the antidumping duty orders on hot-rolled flat-rolled... hot- rolled flat-rolled carbon-quality steel products from Brazil and Japan pursuant to section...

  19. Experience in TMT with the use of cold lengthwise rolling in dead rolls

    NASA Astrophysics Data System (ADS)

    Agas'yants, G. A.; Semibratov, G. G.; Kodjaspirov, G. E.

    2007-01-01

    Experience in the thermomechanical treatment of long stepped preforms for shafts (including torsion ones), studs, forcing bolts, and other articles from high-strength and maraging steels with the use of cold lengthwise rolling in dead rolls is described. The used variants of TMT make it possible to obtain hardened highly loaded machine parts with high quality and performance parameters.

  20. Influence of Carbon Content and Rolling Temperature on Rolling Texture in 3 Pct Si Steel

    NASA Astrophysics Data System (ADS)

    Shingaki, Y.; Takashima, M.; Hayakawa, Y.

    2017-01-01

    Effects of carbon and rolling temperature up to 453 K (180 °C) on rolling texture of 3 pct Si steel at a reduction of 66 pct were investigated using a single crystal with an initial orientation of {110}<001>. With residual-level carbon, uniform slip deformation was observed in the specimen cold rolled at room temperature and most of initial orientation {110}<001> rotated to {111}<112> during the rolling. With carbon addition, the formation of the deformation twins and the shear bands were promoted in the specimen cold rolled at room temperature. Regions with {110}<001> were observed inside the shear bands. Warm-rolled specimen with residual-level carbon had microbands containing tiny {110}<001> regions. Warm-rolled specimen with carbon addition had both the shear bands and the microbands but no deformation twin. Additionally, there were unique band structures with rotated crystal orientation around the rolling direction from initial orientation {110}<001>. These experimental results suggest that the carbon addition inhibits dislocation migration by the increase of the critical resolved shear stress (CRSS) and that the high deformation temperature activates multiple slip systems by the reduction of CRSS and further that the carbon addition and high deformation temperature superimposed bring about the activation of symmetrical {110} slip systems additionally.

  1. Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery

    SciTech Connect

    2001-10-01

    The project goal is to develop a numerical modeling capability to optimize the hot rolling process used to produce aluminum plate. This tool will be used in the forming process so that loss of product will be minimized. Product lost in the rolling process requires the energy-intensive steps of remelting and reforming into an ingot.

  2. Comparing Acute Bouts of Sagittal Plane Progression Foam Rolling vs. Frontal Plane Progression Foam Rolling.

    PubMed

    Peacock, Corey A; Krein, Darren D; Antonio, Jose; Sanders, Gabriel J; Silver, Tobin A; Colas, Megan

    2015-08-01

    Many strength and conditioning professionals have included the use of foam rolling devices within a warm-up routine prior to both training and competition. Multiple studies have investigated foam rolling in regards to performance, flexibility, and rehabilitation; however, additional research is necessary in supporting the topic. Furthermore, as multiple foam rolling progressions exist, researching differences that may result from each is required. To investigate differences in foam rolling progressions, 16 athletically trained males underwent a 2-condition within-subjects protocol comparing the differences of 2 common foam rolling progressions in regards to performance testing. The 2 conditions included a foam rolling progression targeting the mediolateral axis of the body (FRml) and foam rolling progression targeting the anteroposterior axis (FRap). Each was administered in adjunct with a full-body dynamic warm-up. After each rolling progression, subjects performed National Football League combine drills, flexibility, and subjective scaling measures. The data demonstrated that FRml was effective at improving flexibility (p ≤ 0.05) when compared with FRap. No other differences existed between progressions.

  3. Practice of Improving Roll Deformation Theory in Strip Rolling Process Based on Boundary Integral Equation Method

    NASA Astrophysics Data System (ADS)

    Yuan, Zhengwen; Xiao, Hong; Xie, Hongbiao

    2014-02-01

    Precise strip-shape control theory is significant to improve rolled strip quality, and roll flattening theory is a primary part of the strip-shape theory. To improve the accuracy of roll flattening calculation based on semi-infinite body model, a new and more accurate roll flattening model is proposed in this paper, which is derived based on boundary integral equation method. The displacement fields of the finite length semi-infinite body on left and right sides are simulated by using finite element method (FEM) and displacement decay functions on left and right sides are established. Based on the new roll flattening model, a new 4Hi mill deformation model is established and verified by FEM. The new model is compared with Foppl formula and semi-infinite body model in different strip width, roll shifting value and bending force. The results show that the pressure and flattening between rolls calculated by the new model are more precise than other two models, especially near the two roll barrel edges.

  4. Sensitivity analysis of roll load, torque and material properties in the roll forming process

    NASA Astrophysics Data System (ADS)

    Abeyrathna, Buddhika; Rolfe, Bernard; Hodgson, Peter; Weiss, Matthias

    2013-12-01

    Advanced High Strength Steel (AHSS) and Ultra High Strength Steel (UHSS) are increasingly used in the current automotive industry because of their high strength and weight saving potential. As a sheet forming process, roll forming is capable of forming such materials with precise dimensions, however a small change in processing may results in significant change in the material properties such as yield strength and hardening exponent from coil to coil or within the same coil. This paper presents the effect of yield strength and the hardening exponent on roll load, torque of the roll forming process and the longitudinal bow. The roll forming process is numerically simulated, and then the regression analysis and Analysis of Variance (ANOVA) techniques are employed to establish the relationships among the aforementioned parameters and to determine the percentage influence of material properties on longitudinal bow, roll load and torque.

  5. Research on the rolling moment in the symmetrical and asymmetrical rolling process

    NASA Astrophysics Data System (ADS)

    Alexa, V.; Raţiu, S. A.; Kiss, I.; Cioată, C. G.

    2017-01-01

    Research distribution the rolling moments symmetrical and asymmetrical report presents great importance both in theory and to introduce clarifications to the calculation of rolling resistance line assemblies. Clarifying individuals of metallic material deformation between the rolls single cylinder diameters act of any difference of work and analysis of advance and delay phenomena. Torque drive value for each of the rolling cylinders was done by reducing the thickness of the laminate samples, an experimental facility located in the laboratory of plastic deformation of the Faculty of Engineering Hunedoara. The analysis of research results show that in terms of power consumption for deformation and safety equipment in operation is rational for mills which require such a difference between the work rolls to execute about one cylinder operated.

  6. Applying contextual interference to the Pawlata roll.

    PubMed

    Smith, P J; Davies, M

    1995-12-01

    Contextual interference is manipulated by changing the practice order of a number of similar motor tasks, so that the learning context of each interferes with that of the other. The effect has been found to generalize to baseball batting, badminton serving and volleyball skills. The present study examined whether this practice technique could be applied to a Pawlata roll in a kayak. The study was further motivated by the fact that many instructors in Britain currently advocate learning the Pawlata roll in one direction only to a criterion of accuracy, thereafter transferring to the opposite direction. Contextual interference literature predicts that skill retention would be better served by practising on alternate sides. Accordingly, 16 undergraduate students with no kayaking experience were randomly allocated to either a low contextual interference group, which followed U'ren's (1993) recommendations, or a high contextual interference group, which practised the skill on alternate sides. The high contextual interference group took less time to acquire the skill, and were also quicker to achieve successful performance in retention (full roll) and transfer (half roll) tests, regardless of the direction of the roll, 1 week later. The time savings in practice were not expected, as acquisition under high contextual interference was improved rather than impaired. This finding suggests that bilateral transfer was increased by randomizing practice. These results are worthy of further investigation, in that they suggest that the recommended training methods may not be optimal.

  7. Magnon inflation: slow roll with steep potentials

    SciTech Connect

    Adshead, Peter; Blas, Diego; Burgess, C.P.; Hayman, Peter; Patil, Subodh P.

    2016-11-04

    We find multi-scalar effective field theories (EFTs) that can achieve a slow inflationary roll despite having a scalar potential that does not satisfy G{sup ab}∂{sub a}V∂{sub b}V≪V{sup 2}/M{sub p}{sup 2} (where G{sub ab} is the target-space metric). They evade the usual slow-roll conditions on V because their kinetic energies are dominated by single-derivative terms rather than the usual two-derivative terms. Single derivatives dominate during slow roll and so do not require a breakdown of the usual derivative expansion that underpins calculational control in much of cosmology. The presence of such terms requires some sort of UV Lorentz-symmetry breaking during inflation (besides the usual cosmological breaking). Chromo-natural inflation provides one particular example of a UV theory that can generate the multi-field single-derivative terms we consider, and we argue that the EFT we find indeed captures the slow-roll conditions for its background evolution. We also show that our EFT can be understood as a multi-field generalization of the single-field Cuscuton models. The multi-field case introduces a new feature, however: the scalar kinetic terms define a target-space 2-form, F{sub ab}, whose antisymmetry gives new ways for slow roll to be achieved.

  8. Magnon inflation: slow roll with steep potentials

    NASA Astrophysics Data System (ADS)

    Adshead, Peter; Blas, Diego; Burgess, C. P.; Hayman, Peter; Patil, Subodh P.

    2016-11-01

    We find multi-scalar effective field theories (EFTs) that can achieve a slow inflationary roll despite having a scalar potential that does not satisfy Script Gab ∂a V ∂b V ll V2/Mp2 (where Script Gab is the target-space metric). They evade the usual slow-roll conditions on V because their kinetic energies are dominated by single-derivative terms rather than the usual two-derivative terms. Single derivatives dominate during slow roll and so do not require a breakdown of the usual derivative expansion that underpins calculational control in much of cosmology. The presence of such terms requires some sort of UV Lorentz-symmetry breaking during inflation (besides the usual cosmological breaking). Chromo-natural inflation provides one particular example of a UV theory that can generate the multi-field single-derivative terms we consider, and we argue that the EFT we find indeed captures the slow-roll conditions for its background evolution. We also show that our EFT can be understood as a multi-field generalization of the single-field Cuscuton models. The multi-field case introduces a new feature, however: the scalar kinetic terms define a target-space 2-form, ℱab, whose antisymmetry gives new ways for slow roll to be achieved.

  9. A Roll, Fin, and Fin Controller Prediction Computer Program.

    DTIC Science & Technology

    1980-06-01

    Reference 1, and specific details of this improve- ment will be published in a future report currently under preparation by Cox. *A complete listing of...effects. CONCLUDING RMARKS This report provides a user’s guide to FINCON, a roll, fin, fin con- troller prediction computer program. No attempt to...180. FLOATIMUOIINU) ROLL I# OA14PUINUI a OUCIIV,1 ROLL 19 IF ( ITEPATE .EQ.0) O T3 98’ ROLL 106 Ise NTIY 0 ROLL lot To 0.0 ROLL lit s0 NTRY - NTYRY I

  10. Rolling Element Bearing Stiffness Matrix Determination (Presentation)

    SciTech Connect

    Guo, Y.; Parker, R.

    2014-01-01

    Current theoretical bearing models differ in their stiffness estimates because of different model assumptions. In this study, a finite element/contact mechanics model is developed for rolling element bearings with the focus of obtaining accurate bearing stiffness for a wide range of bearing types and parameters. A combined surface integral and finite element method is used to solve for the contact mechanics between the rolling elements and races. This model captures the time-dependent characteristics of the bearing contact due to the orbital motion of the rolling elements. A numerical method is developed to determine the full bearing stiffness matrix corresponding to two radial, one axial, and two angular coordinates; the rotation about the shaft axis is free by design. This proposed stiffness determination method is validated against experiments in the literature and compared to existing analytical models and widely used advanced computational methods. The fully-populated stiffness matrix demonstrates the coupling between bearing radial, axial, and tilting bearing deflections.

  11. Controlling roll perturbations in fruit flies

    PubMed Central

    Beatus, Tsevi; Guckenheimer, John M.; Cohen, Itai

    2015-01-01

    Owing to aerodynamic instabilities, stable flapping flight requires ever-present fast corrective actions. Here, we investigate how flies control perturbations along their body roll angle, which is unstable and their most sensitive degree of freedom. We glue a magnet to each fly and apply a short magnetic pulse that rolls it in mid-air. Fast video shows flies correct perturbations up to 100° within 30 ± 7 ms by applying a stroke-amplitude asymmetry that is well described by a linear proportional–integral controller. For more aggressive perturbations, we show evidence for nonlinear and hierarchical control mechanisms. Flies respond to roll perturbations within 5 ms, making this correction reflex one of the fastest in the animal kingdom. PMID:25762650

  12. Computer-aided roll pass design in rolling of airfoil shapes

    NASA Technical Reports Server (NTRS)

    Akgerman, N.; Lahoti, G. D.; Altan, T.

    1980-01-01

    This paper describes two computer-aided design (CAD) programs developed for modeling the shape rolling process for airfoil sections. The first program, SHPROL, uses a modular upper-bound method of analysis and predicts the lateral spread, elongation, and roll torque. The second program, ROLPAS, predicts the stresses, roll separating force, the roll torque and the details of metal flow by simulating the rolling process, using the slab method of analysis. ROLPAS is an interactive program; it offers graphic display capabilities and allows the user to interact with the computer via a keyboard, CRT, and a light pen. The accuracy of the computerized models was evaluated by (a) rolling a selected airfoil shape at room temperature from 1018 steel and isothermally at high temperature from Ti-6Al-4V, and (b) comparing the experimental results with computer predictions. The comparisons indicated that the CAD systems, described here, are useful for practical engineering purposes and can be utilized in roll pass design and analysis for airfoil and similar shapes.

  13. Routh symmetry in the Chaplygin's rolling ball

    NASA Astrophysics Data System (ADS)

    Kim, Byungsoo

    2011-12-01

    The Routh integral in the symmetric Chaplygin's rolling ball has been regarded as a mysterious conservation law due to its interesting form of sqrt {I_1 I_3 + m< {I_s ,s} rangle } Ω _3 . In this paper, a new form of the Routh integral is proposed as a Noether's pairing form of a conservation law. An explicit symmetry vector for the Routh integral is proved to associate the conserved quantity with the invariance of the Lagrangian function under the rollingly constrained nonholonomic variation. Then, the form of the Routh symmetry vector is discussed for its origin as the linear combination of the configurational vectors.

  14. Rolling friction on a granular medium

    NASA Astrophysics Data System (ADS)

    de Blasio, Fabio Vittorio; Saeter, May-Britt

    2009-02-01

    We present experimental results for the rolling of spheres on a granular bed. We use two sets of glass and steel spheres with varying diameters and a high-speed camera to follow the motion of the spheres. Despite the complex phenomena occurring during the rolling, the results show a friction coefficient nearly independent of the velocity (0.45-0.5 for glass and 0.6-0.65 for steel). It is found that for a given sphere density, the large spheres reach a longer distance, a result that may also help explain the rock sorting along natural stone accumulations at the foot of mountain slopes.

  15. Roll ring assemblies for the Space Station

    NASA Technical Reports Server (NTRS)

    Batista, J.; Vise, J.; Young, K.

    1994-01-01

    Space Station Freedom requires the transmission of high power and signals through three different rotational interfaces. Roll ring technology was baselined by NASA for rotary joints to transfer up to 65.5 kW of power for 30 years at greater than 99 percent efficiency. Signal transfer requirements included MIL-STD-1553 data transmission and 4.5 MHz RS250A base and color video. A unique design for each rotary joint was developed and tested to accomplish power and signal transfer. An overview of roll ring technology is presented, followed by design requirements, hardware configuration, and test results.

  16. Stress evaluations under rolling/sliding contacts

    NASA Technical Reports Server (NTRS)

    Kannel, J. W.; Tevaarwerk, J. L.

    1981-01-01

    The state of stress beneath traction drive type of contacts were analyzed. Computing stresses and stress reversals on various planes for points beneath the surface were examined. The effect of tangential and axial friction under gross slip conditions is evaluated with the models. Evaluations were performed on an RC (rolling contact) tester configuration and it is indicated that the classical fatigue stresses are not altered by friction forces typical of lubricated contact. Higher values of friction can result in surface shear reversal that exceeds the stresses at the depth of maximum shear reversal under rolling contact.

  17. Integrated aeroservoelastic synthesis for roll control

    NASA Technical Reports Server (NTRS)

    Nam, Chang-Ho; Weisshaar, Terrence A.

    1990-01-01

    The objective of this study is to illustrate an integrated, parallel design procedure for optimal structural, aerodynamic, and aileron synthesis of an aircraft wing. The effects of combining weight minimization with structural tailoring (ply orientation and thickness) of a lifting surface, together with the wing geometry (sweep angle and taper ratio), and the aileron geometry (spanwise location and chordwise size) upon the lateral control effectiveness are discussed. Several optimization studies for the minimization of aileron hinge moment and wing weight, subject to a specified constant aircraft roll rate at a design airspeed (roll effectiveness), are performed.

  18. Cross-directional interlocking of rolls in an air press of a papermaking machine

    DOEpatents

    Beck, David A.; Gorshe, Thomas

    2003-05-13

    An air press for pressing a paper web is composed of a plurality of rolls including at least a first roll and a second roll. The first roll and the second roll are positioned adjacent one another and form a first nip therebetween. Further, the first roll and the second roll each have a roll end, the roll end of the first roll adjoining the roll end of the second roll. A bevel plate is attached to the roll end of the first roll, the bevel plate having at least a first angled plate face. A seal ring is positioned adjacent the roll end of the second roll, the seal ring being juxtaposed to the bevel plate. The seal ring has at least a first angled ring face, and the first angled ring face mates with the first angled plate face.

  19. T Strip Properties Fabricated by Powder Rolling Method

    NASA Astrophysics Data System (ADS)

    Hong, Jae-Keun; Lee, Chae-Hun; Kim, Jeoung-Han; Yeom, Jong-Taek; Park, Nho-Kwang

    In the present study, the characteristics of the Ti powders fabricated by Hydride-Dehydride (HDH) were analyzed in terms of particle shape, size and size distribution. Ti powders were subjected to roll compaction and their microstructure and green densities were evaluated in terms of particle size, powder morphology, roll gap and rolling speed. Effects of blending elements having different powder sizes on densification properties were analyzed. The strip thickness was proportional to the roll gap up to 0.9 mm and the density of titanium strip was decreased with the increase in roll gap. As the roll speed increased, the strip density and thickness were decreased by using -200 mesh Ti powder. However, the effect of rolling speed for -400 mesh Ti powder was not greater than that of -200 mesh powder. The highest density by 93% was achieved by using -400 mesh Ti powder at 0.1 mm roll gap, however edge cracks and alligator cracks were occurred.

  20. Detail from roadbed showing sprocket teeth in rolling segment and ...

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

    Detail from roadbed showing sprocket teeth in rolling segment and typical lateral bracing. View south - New York, New Haven & Hartford Railroad, Fort Point Channel Rolling Lift Bridge, Spanning Fort Point Channel, Boston, Suffolk County, MA

  1. 46 CFR 28.575 - Severe wind and roll.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Severe wind and roll. 28.575 Section 28.575 Shipping... INDUSTRY VESSELS Stability § 28.575 Severe wind and roll. (a) Each vessel must meet paragraphs (f) and (g) of this section when subjected to the gust wind heeling arm and the angle of roll to windward...

  2. 46 CFR 28.575 - Severe wind and roll.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Severe wind and roll. 28.575 Section 28.575 Shipping... INDUSTRY VESSELS Stability § 28.575 Severe wind and roll. (a) Each vessel must meet paragraphs (f) and (g) of this section when subjected to the gust wind heeling arm and the angle of roll to windward...

  3. Conceptualizing Rolling Motion Through an Extreme Case Reasoning Approach

    NASA Astrophysics Data System (ADS)

    Hasović, Elvedin; Mešić, Vanes; Erceg, Nataša

    2017-03-01

    In this paper we are going to show how learning about some counterintuitive aspects of rolling motion can be facilitated by combining the use of analogies with extreme case reasoning. Specifically, the intuitively comprehensible examples of "rolling" polygonal prisms are used as an analogical anchor that is supposed to help the students develop conceptual understanding about counterintuitive aspects of rolling motion.

  4. 15. VIEW OF ROLLING OPERATION. INGOTS AND BAR STOCK WERE ...

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

    15. VIEW OF ROLLING OPERATION. INGOTS AND BAR STOCK WERE ROLLED TO A SPECIFIED THICKNESS IN PREPARATION FOR FURTHER PROCESSING. (11/82) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  5. 25 CFR 75.15 - Current membership roll.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Current membership roll. 75.15 Section 75.15 Indians... THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.15 Current membership roll. The membership roll of the Eastern Band of Cherokee Indians shall be kept current by striking therefrom the names...

  6. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  7. 25 CFR 75.15 - Current membership roll.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Current membership roll. 75.15 Section 75.15 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.15 Current membership roll. The...

  8. 25 CFR 75.4 - Basic membership roll.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Basic membership roll. 75.4 Section 75.4 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.4 Basic membership roll. All persons...

  9. 25 CFR 75.15 - Current membership roll.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Current membership roll. 75.15 Section 75.15 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.15 Current membership roll. The...

  10. 25 CFR 75.4 - Basic membership roll.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Basic membership roll. 75.4 Section 75.4 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.4 Basic membership roll. All persons whose...

  11. 25 CFR 75.4 - Basic membership roll.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Basic membership roll. 75.4 Section 75.4 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.4 Basic membership roll. All persons...

  12. 25 CFR 75.4 - Basic membership roll.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Basic membership roll. 75.4 Section 75.4 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.4 Basic membership roll. All persons...

  13. 25 CFR 75.15 - Current membership roll.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Current membership roll. 75.15 Section 75.15 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.15 Current membership roll. The...

  14. 46 CFR 56.30-15 - Expanded or rolled joints.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Expanded or rolled joints. 56.30-15 Section 56.30-15... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-15 Expanded or rolled joints. (a) Expanded or rolled joints may be used where experience or test has demonstrated that the joint is suitable for...

  15. 46 CFR 56.30-15 - Expanded or rolled joints.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Expanded or rolled joints. 56.30-15 Section 56.30-15... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-15 Expanded or rolled joints. (a) Expanded or rolled joints may be used where experience or test has demonstrated that the joint is suitable for...

  16. 46 CFR 56.30-15 - Expanded or rolled joints.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Expanded or rolled joints. 56.30-15 Section 56.30-15... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-15 Expanded or rolled joints. (a) Expanded or rolled joints may be used where experience or test has demonstrated that the joint is suitable for...

  17. 46 CFR 56.30-15 - Expanded or rolled joints.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Expanded or rolled joints. 56.30-15 Section 56.30-15... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-15 Expanded or rolled joints. (a) Expanded or rolled joints may be used where experience or test has demonstrated that the joint is suitable for...

  18. 46 CFR 56.30-15 - Expanded or rolled joints.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Expanded or rolled joints. 56.30-15 Section 56.30-15... APPURTENANCES Selection and Limitations of Piping Joints § 56.30-15 Expanded or rolled joints. (a) Expanded or rolled joints may be used where experience or test has demonstrated that the joint is suitable for...

  19. 14. VIEW OF METAL ROLLING OPERATION. THE METALS ARE BEING ...

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

    14. VIEW OF METAL ROLLING OPERATION. THE METALS ARE BEING PREPARED TO BE ROLLED INTO SHEETS OF SPECIFIC THICKNESS. COMPONENT PARTS WERE FABRICATED FROM THE METAL SHEETS. (11/82) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  20. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  1. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  2. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  3. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  4. Discrete particle modelling of granular roll waves

    NASA Astrophysics Data System (ADS)

    Tsang, Jonathan; Dalziel, Stuart; Vriend, Nathalie

    2016-11-01

    A granular current flowing down an inclined chute or plane can undergo an instability that leads to the formation of surface waves, known as roll waves. Examples of roll waves are found in avalanches and debris flows in landslides, and in many industrial processes. Although related to the Kapitza instability of viscous fluid films, granular roll waves are not yet as well understood. Laboratory experiments typically measure the surface height and velocity of a current as functions of position and time, but they do not give insight into the processes below the surface: in particular, the possible formation of a boundary layer at the free surface as well as the base. To overcome this, we are running discrete particle model (DPM) simulations. Simulations are validated against our laboratory experiments, but they also allow us to examine a much larger range of parameters, such as material properties, chute geometry and particle size dispersity, than that which is possible in the lab. We shall present results from simulations in which we vary particle size and dispersity, and examine the implications on roll wave formation and propagation. Future work will include simulations in which the shape of the chute is varied, both cross-sectionally and in the downstream direction. EPSRC studentship (Tsang) and Royal Society Research Fellowship (Vriend).

  5. Malaria. Can WHO roll back malaria?

    PubMed

    Balter, M

    2000-10-20

    In October 1998, World Health Organization Director-General Gro Harlem Brundtland announced Roll Back Malaria, a multiagency crusade that aims to cut malaria mortality in half over the next 10 years. Brundtland might just be the one to pull it off, say numerous public health experts, although some researchers question whether the goal is realistic.

  6. 9 CFR 381.159 - Poultry rolls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Poultry rolls. 381.159 Section 381.159... ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition §...

  7. 9 CFR 381.159 - Poultry rolls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Poultry rolls. 381.159 Section 381.159... ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition §...

  8. 9 CFR 381.159 - Poultry rolls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Poultry rolls. 381.159 Section 381.159... ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition §...

  9. 9 CFR 381.159 - Poultry rolls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Poultry rolls. 381.159 Section 381.159... ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition §...

  10. 9 CFR 381.159 - Poultry rolls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Poultry rolls. 381.159 Section 381.159... ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition §...

  11. Land rolling increases broadleaf weed emergence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the northern Great Plains, annual forage and pulse crops typically are land rolled after planting to push rocks back into the soil to prevent damage to harvest equipment. Packer wheels commonly are used at planting to improve soil-seed contact for more uniform crop emergence and subsequent matur...

  12. Tool For Robotic Resistive Roll Welding

    NASA Technical Reports Server (NTRS)

    Gilber, Jeffrey L.

    1991-01-01

    Roll-welding attachment for robot simple, inexpensive device incorporating modified commercial resistance-welding gun. Modified welding gun easily attaches to end effector of robot. Robot applies welding force and moves electrode wheel along prescribed path. Resistance-welding current starts and stops automatically according to force exerted against workpiece. Used to apply brazing foil to workpiece.

  13. 14 CFR 23.349 - Rolling conditions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Rolling conditions. The wing and wing bracing must be designed for the following loading conditions: (a) Unsymmetrical wing loads appropriate to the category. Unless the following values result in unrealistic loads... semispan wing airload acts on one side of the plane of symmetry and 60 percent of this load acts on...

  14. 14 CFR 23.349 - Rolling conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Rolling conditions. The wing and wing bracing must be designed for the following loading conditions: (a) Unsymmetrical wing loads appropriate to the category. Unless the following values result in unrealistic loads... semispan wing airload acts on one side of the plane of symmetry and 60 percent of this load acts on...

  15. 14 CFR 23.349 - Rolling conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Rolling conditions. The wing and wing bracing must be designed for the following loading conditions: (a) Unsymmetrical wing loads appropriate to the category. Unless the following values result in unrealistic loads... semispan wing airload acts on one side of the plane of symmetry and 60 percent of this load acts on...

  16. 14 CFR 23.349 - Rolling conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Rolling conditions. The wing and wing bracing must be designed for the following loading conditions: (a) Unsymmetrical wing loads appropriate to the category. Unless the following values result in unrealistic loads... semispan wing airload acts on one side of the plane of symmetry and 60 percent of this load acts on...

  17. 14 CFR 23.349 - Rolling conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Rolling conditions. The wing and wing bracing must be designed for the following loading conditions: (a) Unsymmetrical wing loads appropriate to the category. Unless the following values result in unrealistic loads... semispan wing airload acts on one side of the plane of symmetry and 60 percent of this load acts on...

  18. Rolling Friction on a Wheeled Laboratory Cart

    ERIC Educational Resources Information Center

    Mungan, Carl E.

    2012-01-01

    A simple model is developed that predicts the coefficient of rolling friction for an undriven laboratory cart on a track that is approximately independent of the mass loaded onto the cart and of the angle of inclination of the track. The model includes both deformation of the wheels/track and frictional torque at the axles/bearings. The concept of…

  19. Large Scale Evaluation fo Nickel Aluminide Rolls

    SciTech Connect

    2005-09-01

    This completed project was a joint effort between Oak Ridge National Laboratory and Bethlehem Steel (now Mittal Steel) to demonstrate the effectiveness of using nickel aluminide intermetallic alloy rolls as part of an updated, energy-efficient, commercial annealing furnace system.

  20. Oscillations and Rolling for Duffing's Equation

    NASA Astrophysics Data System (ADS)

    Aref'eva, I. Ya.; Piskovskiy, E. V.; Volovich, I. V.

    2013-01-01

    The Duffing equation has been used to model nonlinear dynamics not only in mechanics and electronics but also in biology and in neurology for the brain process modeling. Van der Pol's method is often used in nonlinear dynamics to improve perturbation theory results when describing small oscillations. However, in some other problems of nonlinear dynamics particularly in case of Duffing-Higgs equation in field theory, for the Einsten-Friedmann equations in cosmology and for relaxation processes in neurology not only small oscillations regime is of interest but also the regime of slow rolling. In the present work a method for approximate solution to nonlinear dynamics equations in the rolling regime is developed. It is shown that in order to improve perturbation theory in the rolling regime it turns out to be effective to use an expansion in hyperbolic functions instead of trigonometric functions as it is done in van der Pol's method in case of small oscillations. In particular the Duffing equation in the rolling regime is investigated using solution expressed in terms of elliptic functions. Accuracy of obtained approximation is estimated. The Duffing equation with dissipation is also considered.

  1. Antares Rolls Out to Wallops Launch Pad

    NASA Video Gallery

    Orbital Sciences Corporation’s Antares rocket rolls out to the launch pad at NASA’s Wallops Flight Facility on the morning of Oct. 1, 2012. Over the next several months, Orbital plans a hot-fir...

  2. Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery

    SciTech Connect

    Couch, R; Becker, R; Rhee, M; Li, M

    2004-09-24

    Lawrence Livermore National Laboratory participated in a U. S. Department of Energy/Office of Industrial Technology sponsored research project 'Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery', as a Cooperative Agreement TC-02028 with the Alcoa Technical Center (ATC). The objective of the joint project with Alcoa is to develop a numerical modeling capability to optimize the hot rolling process used to produce aluminum plate. Product lost in the rolling process and subsequent recycling, wastes resources consumed in the energy-intensive steps of remelting and reprocessing the ingot. The modeling capability developed by project partners will be used to produce plate more efficiently and with reduced product loss.

  3. Conical Euler analysis and active roll suppression for unsteady vortical flows about rolling delta wings

    NASA Technical Reports Server (NTRS)

    Lee-Rausch, Elizabeth M.; Batina, John T.

    1993-01-01

    A conical Euler code was developed to study unsteady vortex-dominated flows about rolling, highly swept delta wings undergoing either forced motions or free-to-roll motions that include active roll suppression. The flow solver of the code involves a multistage, Runge-Kutta time-stepping scheme that uses a cell-centered, finite-volume, spatial discretization of the Euler equations on an unstructured grid of triangles. The code allows for the additional analysis of the free to-roll case by simultaneously integrating in time the rigid-body equation of motion with the governing flow equations. Results are presented for a delta wing with a 75 deg swept, sharp leading edge at a free-stream Mach number of 1.2 and at 10 deg, 20 deg, and 30 deg angle of attack alpha. At the lower angles of attack (10 and 20 deg), forced-harmonic analyses indicate that the rolling-moment coefficients provide a positive damping, which is verified by free-to-roll calculations. In contrast, at the higher angle of attack (30 deg), a forced-harmonic analysis indicates that the rolling-moment coefficient provides negative damping at the small roll amplitudes. A free-to-roll calculation for this case produces an initially divergent response, but as the amplitude of motion grows with time, the response transitions to a wing-rock type of limit cycle oscillation, which is characteristic of highly swept delta wings. This limit cycle oscillation may be actively suppressed through the use of a rate-feedback control law and antisymmetrically deflected leading-edge flaps. Descriptions of the conical Euler flow solver and the free-to roll analysis are included in this report. Results are presented that demonstrate how the systematic analysis of the forced response of the delta wing can be used to predict the stable, neutrally stable, and unstable free response of the delta wing. These results also give insight into the flow physics associated with unsteady vortical flows about delta wings undergoing forced

  4. Laser direct write system for fabricating seamless roll-to-roll lithography tools

    NASA Astrophysics Data System (ADS)

    Petrzelka, Joseph E.; Hardt, David E.

    2013-03-01

    Implementations of roll to roll contact lithography require new approaches towards manufacturing tooling, including stamps for roll to roll nanoimprint lithography (NIL) and soft lithography. Suitable roll based tools must have seamless micro- or nano-scale patterns and must be scalable to roll widths of one meter. The authors have developed a new centrifugal stamp casting process that can produce uniform cylindrical polymer stamps in a scalable manner. The pattern on the resulting polymer tool is replicated against a corresponding master pattern on the inner diameter of a centrifuge drum. This master pattern is created in photoresist using a UV laser direct write system. This paper discusses the design and implementation of a laser direct write system targeting the internal diameter of a rotating drum. The design uses flying optics to focus a laser beam along the axis of the centrifuge drum and to redirect the beam towards the drum surface. Experimental patterning results show uniform coatings of negative photoresist in the centrifuge drum that are effectively patterned with a 405 nm laser diode. Seamless patterns are shown to be replicated in a 50 mm diameter, 60 mm long cylindrical stamp made from polydimethylsiloxane (PDMS). Direct write results show gratings with line widths of 10 microns in negative photoresist. Using an FPGA, the laser can be accurately timed against the centrifuge encoder to create complex patterns.

  5. Roll-to-Roll Nanomanufacturing of Hybrid Nanostructures for Energy Storage Device Design.

    PubMed

    Oakes, Landon; Hanken, Trevor; Carter, Rachel; Yates, William; Pint, Cary L

    2015-07-08

    A key limitation to the practical incorporation of nanostructured materials into emerging applications is the challenge of achieving low-cost, high throughput, and highly replicable scalable nanomanufacturing techniques to produce functional materials. Here, we report a benchtop roll-to-roll technique that builds upon the use of binary solutions of nanomaterials and liquid electrophoretic assembly to rapidly construct hybrid materials for battery design applications. We demonstrate surfactant-free hybrid mixtures of carbon nanotubes, silicon nanoparticles, MoS2 nanosheets, carbon nanohorns, and graphene nanoplatelets. Roll-to-roll electrophoretic assembly from these solutions enables the controlled fabrication of homogeneous coatings of these nanostructures that maintain chemical and physical properties defined by the synergistic combination of nanomaterials utilized without adverse effects of surfactants or impurities that typically limit liquid nanomanufacturing routes. To demonstrate the utility of this nanomanufacturing approach, we employed roll-to-roll electrophoretic processing to fabricate both positive and negative electrodes for lithium ion batteries in less than 30 s. The optimized full-cell battery, containing active materials of prelithiated silicon nanoparticles and MoS2 nanosheets, was assessed to exhibit energy densities of 167 Wh/kgcell(-1) and power densities of 9.6 kW/kgcell(-1).

  6. Roll-to-roll embossing of optical linear Fresnel lens polymer film for solar concentration.

    PubMed

    Zhang, XinQuan; Liu, Kui; Shan, Xuechuan; Liu, Yuchan

    2014-12-15

    Roll-to-roll manufacturing has been proven to be a high-throughput and low-cost technology for continuous fabrication of functional optical polymer films. In this paper, we have firstly studied a complete manufacturing cycle of linear Fresnel lens polymer film for solar concentration in the aspects of ultra-precision diamond machining of metal roller mold, roll-to-roll embossing, and measurement on film profile and functionality. A metal roller mold patterned with linear Fresnel lenses is obtained using single point diamond turning technique. The roller mold is installed onto a self-developed roll-to-roll UV embossing system to realize continuous manufacturing of linear Fresnel lens film. Profile measurement of the machined roller mold and the embossed polymer film, which is conducted using a stylus profilometer, shows good agreement between measured facet angles with designed ones. Functionality test is conducted on a solar simulation system with a reference solar cell, and results show that strong light concentration is realized.

  7. High resolution patterning for flexible electronics via roll-to-roll nanoimprint lithography

    NASA Astrophysics Data System (ADS)

    Sabik, Sami; de Riet, Joris; Yakimets, Iryna; Smits, Edsger

    2014-03-01

    Flexible electronics is a growing field and is currently maturing in applications such as displays, smart packaging, organic light-emitting diodes and organic photovoltaic cells. In order to process on flexible substrates at high throughput and large areas, novel patterning techniques will be essential. Conventional optical lithography is limited in throughput as well as resolution, and requires several alignment steps to generate multi-layered patterns, required for applications such as thin-film transistors. It therefore remains a complex and expensive process. Nanoimprint lithography is an emerging alternative to optical lithography, demonstrating patterning capabilities over a wide range of resolutions, from several microns down to a few nanometres. For display applications, nanoimprint lithography can be used to pattern various layers. Micron sized thin-film transistors for backplane can be fabricated where a self-aligned geometry is used to decrease the number of alignment steps, and increase the overlay accuracy. In addition, nano-structures can be used for optical applications such as anti-reflective surfaces and nano patterned transparent electrodes. Imprint lithography is a fully roll-to-roll compatible process and enables large area and high throughput fabrication for flexible electronics. In this paper we discuss the possibilities and the challenges of large area patterning by roll-to-roll nanoimprint lithography, reviewing micron and nano sized structures realized on our roll-to-roll equipment. Nano patterned transparent electrodes, moth-eye antireflective coatings, and multilevel structures will be covered.

  8. 76 FR 36081 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil and Japan: Revocation of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-21

    ... International Trade Administration Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil and Japan... reviews of the antidumping duty (``AD'') orders on certain hot-rolled flat-rolled carbon-quality steel products (``hot-rolled steel'') from Brazil and Japan, and on December 3, 2010, the final results of...

  9. Static measurements of slender delta wing rolling moment hysteresis

    NASA Technical Reports Server (NTRS)

    Katz, Joseph; Levin, Daniel

    1991-01-01

    Slender delta wing planforms are susceptible to self-induced roll oscillations due to aerodynamic hysteresis during the limit cycle roll oscillation. Test results are presented which clearly establish that the static rolling moment hysteresis has a damping character; hysteresis tends to be greater when, due to either wing roll or side slip, the vortex burst moves back and forth over the wing trailing edge. These data are an indirect indication of the damping role of the vortex burst during limit cycle roll oscillations.

  10. Toward large-area roll-to-roll printed nanophotonic sensors

    NASA Astrophysics Data System (ADS)

    Karioja, Pentti; Hiltunen, Jussi; Aikio, Sanna M.; Alajoki, Teemu; Tuominen, Jarkko; Hiltunen, Marianne; Siitonen, Samuli; Kontturi, Ville; Böhlen, Karl; Hauser, Rene; Charlton, Martin; Boersma, Arjen; Lieberzeit, Peter; Felder, Thorsten; Eustace, David; Haskal, Eliav

    2014-05-01

    Polymers have become an important material group in fabricating discrete photonic components and integrated optical devices. This is due to their good properties: high optical transmittance, versatile processability at relative low temperatures and potential for low-cost production. Recently, nanoimprinting or nanoimprint lithography (NIL) has obtained a plenty of research interest. In NIL, a mould is pressed against a substrate coated with a moldable material. After deformation of the material, the mold is separated and a replica of the mold is formed. Compared with conventional lithographic methods, imprinting is simple to carry out, requires less-complicated equipment and can provide high-resolution with high throughput. Nanoimprint lithography has shown potential to become a method for low-cost and high-throughput fabrication of nanostructures. We show the development process of nano-structured, large-area multi-parameter sensors using Photonic Crystal (PC) and Surface Enhanced Raman Scattering (SERS) methodologies for environmental and pharmaceutical applications. We address these challenges by developing roll-to-roll (R2R) UV-nanoimprint fabrication methods. Our development steps are the following: Firstly, the proof of concept structures are fabricated by the use of wafer-level processes in Si-based materials. Secondly, the master molds of successful designs are fabricated, and they are used to transfer the nanophotonic structures into polymer materials using sheet-level UV-nanoimprinting. Thirdly, the sheet-level nanoimprinting processes are transferred to roll-to-roll fabrication. In order to enhance roll-to-roll manufacturing capabilities, silicone-based polymer material development was carried out. In the different development phases, Photonic Crystal and SERS sensor structures with increasing complexities were fabricated using polymer materials in order to enhance sheet-level and roll-to-roll manufacturing processes. In addition, chemical and molecular

  11. Roll casting of Al-SiCp strip

    NASA Astrophysics Data System (ADS)

    Haga, Toshio

    2016-10-01

    A steel roll with a devised cooling water channel for a vertical type high speed twin roll caster was devised, and was used for strip casting of Al-30vol%SiCp. In the proposed roll caster, the thickness of the wall from the water cooling channel to the roll surface was 4 mm to obtain good cooling conditions. The water cooling channel was machined in the roll core in the lateral direction to prevent convex deformation of the roll. The concave thickness distribution of the strip was improved by the proposed roll. The Al-30vol%SiCp strip had a uniform thickness distribution and could be cast at a speed of 60 m/min. The SiC particles were found to be uniformly distributed, with no obvious agglomeration. The eutectic Si particles were globular and smaller than 3 µm due to the rapid solidification.

  12. Rolled fingerprint construction using MRF-based nonrigid image registration.

    PubMed

    Kwon, Dongjin; Yun, Il Dong; Lee, Sang Uk

    2010-12-01

    This paper proposes a new rolled fingerprint construction approach incorporating a state-of-the-art nonrigid image registration method based upon a Markov random field (MRF) energy model. The proposed method finds dense correspondences between images from a rolled fingerprint sequence and warps the entire fingerprint area to synthesize a rolled fingerprint. This method can generate conceptually more accurate rolled fingerprints by preserving the geometric properties of the finger surface as opposed to ink-based rolled impressions and other existing rolled fingerprint construction methods. To verify the accuracy of the proposed method, various comparative experiments were designed to reveal differences among the rolled construction methods. The results show that the proposed method is significantly superior in various aspects compared to previous approaches.

  13. Large slow roll parameters in single field inflation

    SciTech Connect

    Cook, Jessica L.; Krauss, Lawrence M. E-mail: krauss@asu.edu

    2016-03-01

    We initially consider two simple situations where inflationary slow roll parameters are large and modes no longer freeze out shortly after exiting the horizon, treating both cases analytically. By modes, we refer to the comoving curvature perturbation R. We then consider applications to transient phases where the slow roll parameters can become large, especially in the context of the common 'fast-roll' inflation frequently used as a mechanism to explain the anomalously low scalar power at low l in the CMB. These transient cases we treat numerically. We find when ε, the first slow roll parameter, and only ε is large, modes decay outside the horizon, and when δ, the second slow roll parameter, is large, modes grow outside the horizon. When multiple slow roll parameters are large the behavior in general is more complicated, but we nevertheless show in the 'fast-roll' inflation case, modes grow outside the horizon.

  14. Dynamics and Stability of Rolling Viscoelastic Tires

    SciTech Connect

    Potter, Trevor

    2013-04-30

    Current steady state rolling tire calculations often do not include treads because treads destroy the rotational symmetry of the tire. We describe two methodologies to compute time periodic solutions of a two-dimensional viscoelastic tire with treads: solving a minimization problem and solving a system of equations. We also expand on work by Oden and Lin on free spinning rolling elastic tires in which they disovered a hierachy of N-peak steady state standing wave solutions. In addition to discovering a two-dimensional hierarchy of standing wave solutions that includes their N-peak hiearchy, we consider the eects of viscoelasticity on the standing wave solutions. Finally, a commonplace model of viscoelasticity used in our numerical experiments led to non-physical elastic energy growth for large tire speeds. We show that a viscoelastic model of Govindjee and Reese remedies the problem.

  15. Rolling-circle transposons in eukaryotes.

    PubMed

    Kapitonov, V V; Jurka, J

    2001-07-17

    All eukaryotic DNA transposons reported so far belong to a single category of elements transposed by the so-called "cut-and-paste" mechanism. Here, we report a previously unknown category of eukaryotic DNA transposons, Helitron, which transpose by rolling-circle replication. Autonomous Helitrons encode a 5'-to-3' DNA helicase and nuclease/ligase similar to those encoded by known rolling-circle replicons. Helitron-like transposons have conservative 5'-TC and CTRR-3' termini and do not have terminal inverted repeats. They contain 16- to 20-bp hairpins separated by 10--12 nucleotides from the 3'-end and transpose precisely between the 5'-A and T-3', with no modifications of the AT target sites. Together with their multiple diverged nonautonomous descendants, Helitrons constitute approximately 2% of both the Arabidopsis thaliana and Caenorhabditis elegans genomes and also colonize the Oriza sativa genome. Sequence conservation suggests that Helitrons continue to be transposed.

  16. Energy dissipation in a rolling aircraft tire

    NASA Technical Reports Server (NTRS)

    Tielking, John T.

    1988-01-01

    The project is extending an existing finite element tire model to calculate the energy dissipation in a free-rolling aircraft tire and temperature buildup in the tire carcass. The model will provide a means of calculating the influence of tire design on the distribution of tire temperature. Current focus is on energy loss measurements of aircraft tire material. The feasibility of taking test specimens directly from the tire carcass for measurements of viscoelastic properties was demonstrated. The interaction of temperature and frequency effects on material loss properties was studied. The tire model was extended to calculate the cyclic energy change in a tire during rolling under load. Input data representing the 40 by 14 aircraft tire whose material loss properties were measured are being used.

  17. Transfer of adhesive tape between calender rolls

    NASA Astrophysics Data System (ADS)

    Johnson, K. L.; Kauzlarich, J. J.

    2004-03-01

    In the calendering process a tape or sheet of deformable material passes through the nip between hard cylindrical rollers. Usually the rolls are driven at the same peripheral speed, but small differences in speed, often referred to as 'creep', can occur if one of the rolls is externally driven and the other is driven by the friction in the contact. In these circumstances it has been observed that a tape that enters the nip adhering to the driven (slower) surface may transfer at exit to the driving (faster) surface but not the other way round. The mechanics of this transfer process is examined theoretically and experimentally in this paper for the case of double sided adhesive tape. It is argued that on emerging from the nip the tape will separate from the surface at which the shear strain in the adhesive is greater and that for transfer to occur the contact load must be sufficient to cause plastic extension of the tape.

  18. [WHO's malaria program Roll Back Malaria].

    PubMed

    Myrvang, B; Godal, T

    2000-05-30

    Malaria is one of the main health problems in the world with 300-500 millions cases yearly and about one million deaths, mainly children in Sub-Saharan Africa. In the 1990s the malaria problem in Africa has increased, although we have methods to control the disease. In 1998 the new secretary general of WHO, Gro Harlem Brundtland, established the Roll Back Malaria programme, with the aim to markedly reduce malaria morbidity and mortality. Governments in malaria-affected countries have to take the lead in Roll Back Malaria. Their health systems must be improved and malaria control integrated into the general health system, and the methods available for prevention and treatment have to be intensified and improved. At the same time, Roll Back Malaria will encourage and promote malaria research which hopefully will result in new medicines, vaccines and other tools which will improve the chances of reducing malaria-related deaths and suffering. Roll Back Malaria is a cabinet project within the WHO, and the organisation has a key role as manager, co-ordinator and monitor of the project. However, it depends for resources on international support and commitment from other UN bodies, the World Bank, governments in the western world, pharmaceutical industry, philanthropists and other sources. At present an optimistic view prevails, and the preliminary aim, to halve the malaria mortality by the year 2010, seems realistic even with the control methods of today. However, if research efforts result in new and better tools to combat the disease, the task will definitely be easier.

  19. Extreme chirality in Swiss roll metamaterials.

    PubMed

    Demetriadou, A; Pendry, J B

    2009-09-16

    The chiral Swiss roll metamaterial is a resonant, magnetic medium that exhibits a negative refractive band for one-wave polarization. Its unique structure facilitates huge chiral effects: a plane polarized wave propagating through this system can change its polarization by 90° in less than a wavelength. Such chirality is at least 100 times greater than previous structures have achieved. In this paper, we discuss this extreme chiral behaviour with both numerical and analytical results.

  20. Rolling circle amplification of metazoan mitochondrialgenomes

    SciTech Connect

    Simison, W. Brian; Lindberg, D.R.; Boore, J.L.

    2005-07-31

    Here we report the successful use of rolling circle amplification (RCA) for the amplification of complete metazoan mt genomes to make a product that is amenable to high-throughput genome sequencing techniques. The benefits of RCA over PCR are many and with further development and refinement of RCA, the sequencing of organellar genomics will require far less time and effort than current long PCR approaches.

  1. Rolling Bearing Life Prediction, Theory, and Application

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.

    2013-01-01

    A tutorial is presented outlining the evolution, theory, and application of rolling-element bearing life prediction from that of A. Palmgren, 1924; W. Weibull, 1939; G. Lundberg and A. Palmgren, 1947 and 1952; E. Ioannides and T. Harris, 1985; and E. Zaretsky, 1987. Comparisons are made between these life models. The Ioannides-Harris model without a fatigue limit is identical to the Lundberg-Palmgren model. The Weibull model is similar to that of Zaretsky if the exponents are chosen to be identical. Both the load-life and Hertz stress-life relations of Weibull, Lundberg and Palmgren, and Ioannides and Harris reflect a strong dependence on the Weibull slope. The Zaretsky model decouples the dependence of the critical shear stress-life relation from the Weibull slope. This results in a nominal variation of the Hertz stress-life exponent. For 9th- and 8th-power Hertz stress-life exponents for ball and roller bearings, respectively, the Lundberg- Palmgren model best predicts life. However, for 12th- and 10th-power relations reflected by modern bearing steels, the Zaretsky model based on the Weibull equation is superior. Under the range of stresses examined, the use of a fatigue limit would suggest that (for most operating conditions under which a rolling-element bearing will operate) the bearing will not fail from classical rolling-element fatigue. Realistically, this is not the case. The use of a fatigue limit will significantly overpredict life over a range of normal operating Hertz stresses. Since the predicted lives of rolling-element bearings are high, the problem can become one of undersizing a bearing for a particular application.

  2. Modeling recrystallization kinetics during strip rolling

    SciTech Connect

    Sun, W.P.; Hawbolt, E.B.; Meadowcroft, T.R.

    1995-01-01

    In order to simulate the microstructural evolution during hot strip rolling, double-hit compression tests have been carried out on plain carbon steels. Using the softening data obtained by these tests, mathematical models were developed to predict the overall kinetics of static recrystallization under roughing and finishing mill conditions. These models include the effects of deformation temperature, applied strain, strain rate and initial austenite grain size. Predictions based on these models are in reasonable agreement with the present experimental results.

  3. Texture Evolution of a Non-oriented Electrical Steel Cold Rolled at Directions Different from the Hot Rolling Direction

    NASA Astrophysics Data System (ADS)

    He, Youliang; Hilinski, Erik; Li, Jian

    2015-11-01

    With the objective of optimizing the crystallographic texture of non-oriented electrical steel, i.e., reducing the <111>//ND and <110>//RD fibers and promoting the <001>//ND texture, a new rolling scheme was proposed and tested, in which the cold rolling direction (CRD) was intentionally inclined at an angle to the hot rolling direction (HRD) in order to change the orientation flow paths during cold rolling and alter the final texture of the annealed sheets. A non-oriented electrical steel containing 0.88 wt pct Si was hot rolled using conventional routes and annealed, and a number of rectangular plates were cut from the hot band with the longitudinal directions inclined at various angles, i.e., 0, 15, 30, 45, 60, 75, and 90 deg, to the HRD. These plates were then cold rolled along the longitudinal directions with a thickness reduction of 72 pct. The cold-rolled samples were annealed, temper rolled and annealed again (final annealing). The texture evolution during hot rolling, hot band annealing, cold rolling, and final annealing was characterized by electron backscatter diffraction and X-ray diffraction techniques. By changing the CRD with respect to the HRD, the initial texture and the orientation flow paths were altered, which resulted in apparent differences in the textures as compared to conventional cold rolling. After temper rolling and final annealing, the recrystallization textures consisted of mainly a <001>//ND fiber and there was almost no <111>//ND fiber. The sample cold rolled at an angle of 60 deg to the HRD had the strongest texture (intensity almost 2× of conventional rolling) with a maximum at the cube {001}<100> orientation—a magnetically favorable orientation for non-oriented electrical steels.

  4. Rolling element fatigue testing of gear materials

    NASA Technical Reports Server (NTRS)

    Nahm, A. H.

    1978-01-01

    Rolling element fatigue lives of nine alloys were evaluated in Rolling Contact (RC) rigs. Test conditions included a Hertzian stress at 4,826 MPa (700 ksi), a rolling speed of 6.23 m/sec (245 in/sec.). Tests were run with a Type I oil (MIL-L-7808G) at room temperature. B-10 lives (10% failure rate) of alloys were compared versus reference alloys, VIM-VAR AISI M-50 and VAR AISI 9310. Six case carburizing alloys (AISI 9310, CBS600, CBS1000M, EX00014, Vasco X-2 and EX00053) and three through-hardening alloys (AISI M-50, VascoMax 350 and Vasco Matrix 2 evaluated, showed RCF performance inferior or equivalent to that of AISI 9310 and AISI M-50. It was also found that the effects of vacuum melting processes, different tempering temperatures, freezing cycle during heat treating, shot peening, gold plating and chrome plating employed in the present investigation did not significantly affect RCF life.

  5. Airbag roll marks & displaced rocks and soil

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Looking southwest from the lander, soil disturbances indicating the spacecraft rolled through the landing site are visible. Arriving from the east, the lander, still encased in its protective airbags, rolled up a slight rise and then rolled back down to its final position. The inset at left shows displaced rocks near the rock 'Flat Top.' Dark patches of disturbed soil indicate where the rocks had originally rested Both insets show rocks that were pushed into the soil from the weight of the lander, visible from the areas of raised rims of dark, disturbed soil around several rocks. The south summit of Twin Peaks is in the background, while a lander petal, deflated airbag, and rear rover deployment ramp are in the foreground.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

  6. Kinematics and aerodynamics of the velocity vector roll

    NASA Technical Reports Server (NTRS)

    Durham, Wayne C.; Lutze, Frederick H.; Mason, W.

    1993-01-01

    The velocity vector roll is an angular rotation of an aircraft about its instantaneous velocity vector, constrained to be performed at constant angle-of-attack (AOA), no sideslip, and constant velocity. Consideration of the aerodynamic force equations leads to requirements for body-axis yawing and pitching rotations that satisfy these constraints. Here, the body axis rotations, and the constraints, are used in the moment equations to determine the aerodynamic moments required to perform the velocity vector roll. For representative tactical aircraft, the conditions for maximum pitching moment are a function of orientation, occurring at about 90 deg of bank in a level trajectory. Maximum required pitching moment occurs at peak roll rate, and is achieved at AOA above 45 deg. The conditions for maximum rolling moment depend on the value of the roll mode time constant. For a small time constant (fast response) the maximum rolling moment occurs at maximum roll acceleration and zero AOA, largely independent of aircraft orientation; for a large time constant, maximum required rolling moment occurs at maximum roll rate, at maximum AOA, and at 180 deg of bank in level flight. Maximum yawing moment occurs at maximum roll acceleration, maximum AOA, and is largely independent of airplane orientation.

  7. Multi-stage FE simulation of hot ring rolling

    NASA Astrophysics Data System (ADS)

    Wang, C.; Geijselaers, H. J. M.; van den Boogaard, A. H.

    2013-05-01

    As a unique and important member of the metal forming family, ring rolling provides a cost effective process route to manufacture seamless rings. Applications of ring rolling cover a wide range of products in aerospace, automotive and civil engineering industries [1]. Above the recrystallization temperature of the material, hot ring rolling begins with the upsetting of the billet cut from raw stock. Next a punch pierces the hot upset billet to form a hole through the billet. This billet, referred to as preform, is then rolled by the ring rolling mill. For an accurate simulation of hot ring rolling, it is crucial to include the deformations, stresses and strains from the upsetting and piercing process as initial conditions for the rolling stage. In this work, multi-stage FE simulations of hot ring rolling process were performed by mapping the local deformation state of the workpiece from one step to the next one. The simulations of upsetting and piercing stages were carried out by 2D axisymmetric models using adaptive remeshing and element erosion. The workpiece for the ring rolling stage was subsequently obtained after performing a 2D to 3D mapping. The commercial FE package LS-DYNA was used for the study and user defined subroutines were implemented to complete the control algorithm. The simulation results were analyzed and also compared with those from the single-stage FE model of hot ring rolling.

  8. Transparent Conductive AGZO/Ag/AGZO Multilayers on PET Substrate by Roll-to-Roll Sputtering.

    PubMed

    Kim, Taehoon; Park, Kwangwon; Kim, Jongsu

    2016-02-01

    Indium-free Al and Ga-codoped ZnO (AGZO) multilayer films with nanoscale Ag interlayer were deposited by dual target roll-to-roll RF for AGZO and DC sputtering systems for Ag at room temperature for a large scale. The thicknesses of AGZO/Ag/AGZO multilayer were optimized by changing the roll speed: 0.15/1.1/0.15 m/min for AGZO/Ag/AGZO multilayers, respectively. The optimum thicknesses of AGZO/Ag/AGZO multilayer are 9.21, 8.32 and 8.04 nm, respectively. Optimized AGZO/Ag/AGZO multilayer films showed an excellent transparency (84% at 550 nm) and a low sheet resistance (9.2 omega/sq.) on PET substrates for opto-electronic applications. The effects of nanoscale Ag interlayer on optical and electrical properties of AGZO/Ag/AGZO multilayer films were discussed.

  9. Tribological Testing of Anti-Adhesive coatings for Cold Rolling Mill Rolls—Application to TiN-Coated Rolls

    NASA Astrophysics Data System (ADS)

    Ould, Choumad; Gachon, Yves; Montmitonnet, Pierre; Badiche, Xavier

    2011-05-01

    Roll life is a major issue in cold strip rolling. Roll wear may result either in too low roll roughness, bringing friction below the minimum requested for strip entrainment; or it may degrade strip surface quality. On the contrary, adhesive wear and transfer ("roll coating", "pick up") may form a thick metallic deposits on the roll which increases friction excessively and degrades strip surface again [1]. The roll surface, with the help of a materials-adapted lubricant, must therefore possess anti-wear and anti-adhesive properties. Thus, High Speed Steeel (HSS) rolls show superior properties compared with standard Cr-steel rolls due to their high carbide surface coverage. Another way to improve wear and adhesion properties of surfaces is to apply hard metallic (hard-Cr) or ceramic coatings. Chromium is renowned for its excellent anti-wear and anti-adhesive properties and may serve as a reference. Here, as a first step towards alternative, optimised coatings, a PVD TiN coating has been deposited on tool steels, as previous attempts have proved TiN to be rather successful in cold rolling experiments [2,3]. Different tribological tests are reported here, giving insight in both anti-adhesive properties and fatigue life improvement.

  10. Roll-to-roll gravure with nanomaterials for printing smart packaging.

    PubMed

    Jung, Minhun; Kim, Junseok; Koo, Hyunmo; Lee, Wookyu; Subramanian, Vivek; Cho, Gyoujin

    2014-02-01

    Roll-to-roll (R2R) gravure is considered one of the highest throughput tools for manufacturing inexpensive and flexible ubiquitous IT devices called "smart packaging" in which NFC (near-field communication) transponder, sensors, ADC (analog-to-digital converter), simple processor and signage are all integrated on paper or plastic foils. In this review, we show R2R gravure can be employed to print smart packaging, starting from printing simple electrodes, dielectrics, capacitors, diodes and thin film transistors with appropriate nanomaterial-based inks on plastic foils.

  11. Production Of Tandem Amorphous Silicon Alloy Solar Cells In A Continuous Roll-To-Roll Process

    NASA Astrophysics Data System (ADS)

    Izu, Masat; Ovshinsky, Stanford R.

    1983-09-01

    A roll-to-roll plasma deposition machine for depositing multi-layered amorphous alloys has been developed. The plasma deposition machine (approximately 35 ft. long) has multiple deposition areas and processes 16-inch wide stainless steel substrate continuously. Amorphous photovoltaic thin films (less than 1pm) having a six layered structure (PINPIN) are deposited on a roll of 16-inch wide 1000 ft. long stainless steel substrate, continu-ously, in a single pass. Mass production of low-cost tandem amorphous solar cells utilizing roll-to-roll processes is now possible. A commercial plant utilizing this plasma deposition machine for manufacturing tandem amorphous silicon alloy solar cells is now in operation. At Energy Conversion Devices, Inc. (ECD), one of the major tasks of the photovoltaic group has been the scale-up of the plasma deposition process for the production of amorphous silicon alloy solar cells. Our object has been to develop the most cost effective way of producing amorphous silicon alloy solar cells having the highest efficiency. The amorphous silicon alloy solar cell which we produce has the following layer structure: 1. Thin steel substrate. 2. Multi-layered photovoltaic amorphous silicon alloy layers (approximately 1pm thick; tandem cells have six layers). 3. ITO. 4. Grid pattern. 5. Encapsulant. The deposition of the amorphous layer is technologically the key process. It was clear to us from the beginning of this scale-up program that amorphous silicon alloy solar cells produced in wide width, continuous roll-to-roll production process would be ultimate lowest cost solar cells according to the following reasons. First of all, the material cost of our solar cells is low because: (1) the total thickness of active material is less than 1pm, and the material usage is very small; (2) silicon, fluorine, hydrogen, and other materials used in the device are abundant and low cost; (3) thin, low-cost substrate is used; and (4) product yield is high. In

  12. Slow-roll approximation in loop quantum cosmology

    NASA Astrophysics Data System (ADS)

    Luc, Joanna; Mielczarek, Jakub

    2017-01-01

    The slow-roll approximation is an analytical approach to study dynamical properties of the inflationary universe. In this article, systematic construction of the slow-roll expansion for effective loop quantum cosmology is presented. The analysis is performed up to the fourth order in both slow-roll parameters and the parameter controlling the strength of deviation from the classical case. The expansion is performed for three types of the slow-roll parameters: Hubble slow-roll parameters, Hubble flow parameters and potential slow-roll parameters. An accuracy of the approximation is verified by comparison with the numerical phase space trajectories for the case with a massive potential term. The results obtained in this article may be helpful in the search for the subtle quantum gravitational effects with use of the cosmological data.

  13. Multilayer roll bonded aluminium foil: processing, microstructure and flow stress

    SciTech Connect

    Barlow, C.Y.; Nielsen, P.; Hansen, N

    2004-08-02

    Bulk aluminium has been produced by warm-rolling followed by cold-rolling of commercial purity (99% purity) aluminium foil. The bonding appeared perfect from observation with the naked eye, light and transmission electron microscopy. By comparison with bulk aluminium of similar purity (AA1200) rolled to a similar strain (90%RA), the roll-bonded metal showed a much higher density of high-angle grain boundaries, similar strength and improved thermal stability. This study has implications for a number of applications in relation to the processing of aluminium. Roll bonding is of interest as a method for grain size refinement; oxide-containing materials have increased strength, enhanced work-hardening behaviour, and exhibit alterations in recrystallisation behaviour. The behaviour of the hard oxide film is of interest in aluminium processing, and has been investigated by characterising the size and distribution of oxide particles in the roll-bonded samples.

  14. Strip casting with fluxing agent applied to casting roll

    SciTech Connect

    Williams, Robert S.; O'Malley, Ronald J.; Sussman, Richard C.

    1997-01-01

    A strip caster (10) for producing a continuous strip (24) includes a tundish (12) for containing a melt (14), a pair of horizontally disposed water cooled casting rolls (22) and devices (29) for electrostatically coating the outer peripheral chill surfaces (44) of the casting rolls with a powder flux material (56). The casting rolls are juxtaposed relative to one another for forming a pouting basin (18) for receiving the melt through a teeming tube (16) thereby establishing a meniscus (20) between the rolls for forming the strip. The melt is protected from the outside air by a non-oxidizing gas passed through a supply line (28) to a sealing chamber (26). A preferred flux is boron oxide having a melting point of about 550.degree. C. The flux coating enhances wetting of the steel melt to the casting roll and dissolves any metal oxide formed on the roll.

  15. Strip casting with fluxing agent applied to casting roll

    DOEpatents

    Williams, R.S.; O`Malley, R.J.; Sussman, R.C.

    1997-07-29

    A strip caster for producing a continuous strip includes a tundish for containing a melt, a pair of horizontally disposed water cooled casting rolls and devices for electrostatically coating the outer peripheral chill surfaces of the casting rolls with a powder flux material. The casting rolls are juxtaposed relative to one another for forming a pouting basin for receiving the melt through a teeming tube thereby establishing a meniscus between the rolls for forming the strip. The melt is protected from the outside air by a non-oxidizing gas passed through a supply line to a sealing chamber. A preferred flux is boron oxide having a melting point of about 550 C. The flux coating enhances wetting of the steel melt to the casting roll and dissolves any metal oxide formed on the roll. 3 figs.

  16. Development of Rolling Schedules for AZ31 Magnesium Alloy Sheets

    DTIC Science & Technology

    2015-06-01

    received AZ31B, a magnesium (Mg) alloy that contains approximately 3% aluminum and 1% zinc. In particular, we investigated the ability to roll AZ31B to...ARL-TR-7277 ● JUNE 2015 US Army Research Laboratory Development of Rolling Schedules for AZ31 Magnesium Alloy Sheets by...7277 ● JUNE 2015 US Army Research Laboratory Development of Rolling Schedules for AZ31 Magnesium Alloy Sheets by Laszlo Kecskes, Heidi

  17. Vestibular influences on human postural control in combinations of pitch and roll planes reveal differences in spatiotemporal processing.

    PubMed

    Carpenter, M G; Allum, J H; Honegger, F

    2001-09-01

    The present study examined the influence of bilateral peripheral vestibular loss (BVL) in humans on postural responses to multidirectional surface rotations in the pitch and roll planes. Specifically, we examined the effects of vestibular loss on the directional sensitivity, timing, and amplitude of early stretch, balance correcting, and stabilizing reactions in postural leg and trunk muscles as well as changes in ankle torque and trunk angular velocity following multidirectional rotational perturbations of the support surface. Fourteen normal healthy adults and five BVL patients stood on a dual axis rotating platform which rotated 7.5 degrees at 50 degrees/s through eight different directions of pitch and roll combinations separated by 45 degrees. Directions were randomized within a series of 44 perturbation trials which were presented first with eyes open, followed by a second series of trials with eyes closed. Vestibular loss did not influence the range of activation or direction of maximum sensitivity for balance correcting responses (120-220 ms). Response onsets at approximately 120 ms were normal in tibialis anterior (TA), soleus (SOL), paraspinals (PARAS), or quadriceps muscles. Only SOL muscle activity demonstrated a 38- to 45-ms delay for combinations of forward (toe-down) and roll perturbations in BVL patients. The amplitude of balance correcting responses in leg muscles between 120 and 220 ms was, with one exception, severely reduced in BVL patients for eyes open and eyes closed conditions. SOL responses were decreased bilaterally for toe-up and toe-down perturbations, but more significantly reduced in the downhill (load-bearing) leg for combined roll and pitch perturbations. TA was significantly reduced bilaterally for toe-up perturbations, and in the downhill leg for backward roll perturbations. Forward perturbations, however, elicited significantly larger TA activity in BVL between 120 and 220 ms compared to normals, which would act to further

  18. 49 CFR 393.122 - What are the rules for securing paper rolls?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... transported with eyes vertical in a sided vehicle. (1) Paper rolls must be placed tightly against the walls of... paper rolls transported with eyes vertical in a sided vehicle. (1) If a paper roll in a split load is... stacked loads of paper rolls transported with eyes vertical in a sided vehicle. (1) Paper rolls must...

  19. 49 CFR 393.122 - What are the rules for securing paper rolls?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... transported with eyes vertical in a sided vehicle. (1) Paper rolls must be placed tightly against the walls of... paper rolls transported with eyes vertical in a sided vehicle. (1) If a paper roll in a split load is... stacked loads of paper rolls transported with eyes vertical in a sided vehicle. (1) Paper rolls must...

  20. The Effects of Forming Parameters on Conical Ring Rolling Process

    PubMed Central

    Meng, Wen; Zhao, Guoqun; Guan, Yanjin

    2014-01-01

    The plastic penetration condition and biting-in condition of a radial conical ring rolling process with a closed die structure on the top and bottom of driven roll, simplified as RCRRCDS, were established. The reasonable value range of mandrel feed rate in rolling process was deduced. A coupled thermomechanical 3D FE model of RCRRCDS process was established. The changing laws of equivalent plastic strain (PEEQ) and temperature distributions with rolling time were investigated. The effects of ring's outer radius growth rate and rolls sizes on the uniformities of PEEQ and temperature distributions, average rolling force, and average rolling moment were studied. The results indicate that the PEEQ at the inner layer and outer layer of rolled ring are larger than that at the middle layer of ring; the temperatures at the “obtuse angle zone” of ring's cross-section are higher than those at “acute angle zone”; the temperature at the central part of ring is higher than that at the middle part of ring's outer surfaces. As the ring's outer radius growth rate increases at its reasonable value ranges, the uniformities of PEEQ and temperature distributions increase. Finally, the optimal values of the ring's outer radius growth rate and rolls sizes were obtained. PMID:25202716

  1. Overlay accuracy on a flexible web with a roll printing process based on a roll-to-roll system.

    PubMed

    Chang, Jaehyuk; Lee, Sunggun; Lee, Ki Beom; Lee, Seungjun; Cho, Young Tae; Seo, Jungwoo; Lee, Sukwon; Jo, Gugrae; Lee, Ki-yong; Kong, Hyang-Shik; Kwon, Sin

    2015-05-01

    For high-quality flexible devices from printing processes based on Roll-to-Roll (R2R) systems, overlay alignment during the patterning of each functional layer poses a major challenge. The reason is because flexible substrates have a relatively low stiffness compared with rigid substrates, and they are easily deformed during web handling in the R2R system. To achieve a high overlay accuracy for a flexible substrate, it is important not only to develop web handling modules (such as web guiding, tension control, winding, and unwinding) and a precise printing tool but also to control the synchronization of each unit in the total system. A R2R web handling system and reverse offset printing process were developed in this work, and an overlay between the 1st and 2nd layers of ±5μm on a 500 mm-wide film was achieved at a σ level of 2.4 and 2.8 (x and y directions, respectively) in a continuous R2R printing process. This paper presents the components and mechanisms used in reverse offset printing based on a R2R system and the printing results including positioning accuracy and overlay alignment accuracy.

  2. Overlay accuracy on a flexible web with a roll printing process based on a roll-to-roll system

    NASA Astrophysics Data System (ADS)

    Chang, Jaehyuk; Lee, Sunggun; Lee, Ki Beom; Lee, Seungjun; Cho, Young Tae; Seo, Jungwoo; Lee, Sukwon; Jo, Gugrae; Lee, Ki-yong; Kong, Hyang-Shik; Kwon, Sin

    2015-05-01

    For high-quality flexible devices from printing processes based on Roll-to-Roll (R2R) systems, overlay alignment during the patterning of each functional layer poses a major challenge. The reason is because flexible substrates have a relatively low stiffness compared with rigid substrates, and they are easily deformed during web handling in the R2R system. To achieve a high overlay accuracy for a flexible substrate, it is important not only to develop web handling modules (such as web guiding, tension control, winding, and unwinding) and a precise printing tool but also to control the synchronization of each unit in the total system. A R2R web handling system and reverse offset printing process were developed in this work, and an overlay between the 1st and 2nd layers of ±5μm on a 500 mm-wide film was achieved at a σ level of 2.4 and 2.8 (x and y directions, respectively) in a continuous R2R printing process. This paper presents the components and mechanisms used in reverse offset printing based on a R2R system and the printing results including positioning accuracy and overlay alignment accuracy.

  3. Rolls-Royce implementing new production system

    NASA Astrophysics Data System (ADS)

    1982-05-01

    An advanced, integrated manufacturing systems system is being implemented in Rolls-Royce production facilities in order to cut unit production costs by reducing lead times, manning levels and inventories. The topics discussed include the program outline, planned subcontracting, the machining operation that includes isothermal forming of wide-chord hollow blades, carbon fiber production of subsystems including thrust reversers, continuous dress creep feed grinding, the directionally solidified casting facility that can produce single-crystal blades without modification to the casting furnaces, and a robot machining line.

  4. Atlantis begins rolling back to the VAB

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Space Shuttle Atlantis joins blue skies and palm trees on the Florida landscape. Atlantis is rolling back from Launch Pad 39A to the Vehicle Assembly Building so that workers can conduct inspections, make continuity checks and conduct X-ray analysis on the 36 SRB cables located inside each booster's system tunnel. An extensive evaluation of NASA's SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis before launching Jan. 19. The launch has been rescheduled no earlier than Feb. 6.

  5. In-situ Roll-to-Roll Printing of Highly Efficient Organic Solar Cells

    SciTech Connect

    Bao, Zhenan; Toney, Michael; Clancy, Paulette

    2016-05-30

    This project focuses on developing a roll-to-roll printing setup for organic solar cells with the capability to follow the film formation in situ with small and wide angle X-ray scattering, and to improve the performance of printed organic solar cells. We demonstrated the use of the printing setup to capture important aspects of existing industrial printing methods, which ensures that the solar cell performance achieved in our printing experiments would be largely retained in an industrial fabrication process. We employed both known and newly synthesized polymers as the donor and acceptor materials, and we studied the morphological changes in real time during the printing process by X-ray scattering. Our experimental efforts are also accompanied by theoretical modeling of both the fluid dynamic aspects of the printing process and the nucleation and crystallization kinetics during the film formation. The combined insight into the printing process gained from the research provides a detailed understanding of the factors governing the printed solar cell’s performance. Finally using the knowledge we gained, we demonstrated large area ( > 10 cm2) printed organic solar cells with more than 5 percent power conversion efficiency, which is best achieved performance for roll-to-roll printed organic solar cells.

  6. Register Control of Roll-to-Roll Printing System Based on Statistical Approach

    NASA Astrophysics Data System (ADS)

    Kim, Chung Hwan; You, Ha-Il; Jo, Jeongdai

    2013-05-01

    One of the most important requirements when using roll-to-roll printing equipment for multilayer printing is register control. Because multilayer printing requires a printing accuracy of several microns to several tens of microns, depending on the devices and their sizes, precise register control is required. In general, the register errors vary with time, even for one revolution of the plate cylinder. Therefore, more information about the register errors in one revolution of the plate cylinder is required for more precise register control, which is achieved by using multiple register marks in a single revolution of the plate cylinder. By using a larger number of register marks, we can define the value of the register error as a statistical value rather than a single one. The register errors measured from an actual roll-to-roll printing system consist of a linearly varying term, a static offset term, and small fluctuations. The register errors resulting from the linearly varying term and the offset term are compensated for by the velocity and phase control of the plate cylinders, based on the calculated slope and offset of the register errors, which are obtained by the curve-fitting of the data set of register errors. We show that even with the slope and offset compensation of the register errors, a register control performance of within 20 µm can be achieved.

  7. High-speed roll-to-roll manufacturing of graphene using a concentric tube CVD reactor

    PubMed Central

    Polsen, Erik S.; McNerny, Daniel Q.; Viswanath, B.; Pattinson, Sebastian W.; John Hart, A.

    2015-01-01

    We present the design of a concentric tube (CT) reactor for roll-to-roll chemical vapor deposition (CVD) on flexible substrates, and its application to continuous production of graphene on copper foil. In the CTCVD reactor, the thin foil substrate is helically wrapped around the inner tube, and translates through the gap between the concentric tubes. We use a bench-scale prototype machine to synthesize graphene on copper substrates at translation speeds varying from 25 mm/min to 500 mm/min, and investigate the influence of process parameters on the uniformity and coverage of graphene on a continuously moving foil. At lower speeds, high-quality monolayer graphene is formed; at higher speeds, rapid nucleation of small graphene domains is observed, yet coalescence is prevented by the limited residence time in the CTCVD system. We show that a smooth isothermal transition between the reducing and carbon-containing atmospheres, enabled by injection of the carbon feedstock via radial holes in the inner tube, is essential to high-quality roll-to-roll graphene CVD. We discuss how the foil quality and microstructure limit the uniformity of graphene over macroscopic dimensions. We conclude by discussing means of scaling and reconfiguring the CTCVD design based on general requirements for 2-D materials manufacturing. PMID:25997124

  8. Fabrication of ultra-thin nanostructured bimetallic foils by Accumulative Roll Bonding and Asymmetric Rolling

    PubMed Central

    Yu, Hailiang; Lu, Cheng; Tieu, A. Kiet; Godbole, Ajit; Su, Lihong; Sun, Yong; Liu, Mao; Tang, Delin; Kong, Charlie

    2013-01-01

    This paper reports a new technique that combines the features of Accumulative Roll Bonding (ARB) and Asymmetric Rolling (AR). This technique has been developed to enable production of ultra-thin bimetallic foils. Initially, 1.5 mm thick AA1050 and AA6061 foils were roll-bonded using ARB at 200°C, with 50% reduction. The resulting 1.5 mm bimetallic foil was subsequently thinned to 0.04 mm through four AR passes at room temperature. The speed ratio between the upper and lower AR rolls was 1:1.3. The tensile strength of the bimetallic foil was seen to increase with reduction in thickness. The ductility of the foil was seen to reduce upon decreasing the foil thickness from 1.5 mm to 0.14 mm, but increase upon further reduction in thickness from 0.14 mm to 0.04 mm. The grain size was about 140 nm for the AA6061 layer and 235 nm for the AA1050 layer, after the third AR pass. PMID:23918002

  9. Continuous roll-to-roll serpentine deposition for high throughput a-Si PV manufacturing

    SciTech Connect

    Izu, M.; Ovshinsky, H.C.; Deng, X.; Krisko, A.J.; Narasimhan, K.L.; Crucet, R.; Laarman, T.; Myatt, A.; Ovshinsky, S.R.

    1994-12-31

    In order to further improve the economies of scale which are inherent in ECD`s continuous roll-to-roll amorphous silicon alloy solar cell manufacturing process, the authors have developed a concept for a serpentine web plasma CVD deposition process to maximize throughput while keeping the size of the deposition chambers small. When this technique is incorporated into a continuous roll-to-roll PV manufacturing process, it will maximize the throughput for a high volume production plant, reduce the machine cost, improve gas utilization, reduce power consumption, and improve the solar cell stability. To demonstrate the serpentine web deposition concept, the authors have constructed a single loop serpentine deposition chamber to deposit a-Si for n-i-p structure solar cells. During the initial process of optimization, they have produced single-junction a-Si solar cells with 8.6% efficiency, and triple-junction a-Si solar cells with a 9.5% initial efficiency, where the top cell intrinsic layer was deposited in the serpentine deposition chamber.

  10. 75 FR 77828 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Extension of Time Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ... International Trade Administration Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil... the preliminary results of the administrative review of the countervailing duty order on certain hot... December 31, 2008. See Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products From...

  11. Progress in cold roll bonding of metals

    PubMed Central

    Li, Long; Nagai, Kotobu; Yin, Fuxing

    2008-01-01

    Layered composite materials have become an increasingly interesting topic in industrial development. Cold roll bonding (CRB), as a solid phase method of bonding same or different metals by rolling at room temperature, has been widely used in manufacturing large layered composite sheets and foils. In this paper, we provide a brief overview of a technology using layered composite materials produced by CRB and discuss the suitability of this technology in the fabrication of layered composite materials. The effects of process parameters on bonding, mainly including process and surface preparation conditions, have been analyzed. Bonding between two sheets can be realized when deformation reduction reaches a threshold value. However, it is essential to remove surface contamination layers to produce a satisfactory bond in CRB. It has been suggested that the degreasing and then scratch brushing of surfaces create a strong bonding between the layers. Bonding mechanisms, in which the film theory is expressed as the major mechanism in CRB, as well as bonding theoretical models, have also been reviewed. It has also been showed that it is easy for bcc structure metals to bond compared with fcc and hcp structure metals. In addition, hardness on bonding same metals plays an important part in CRB. Applications of composites produced by CRB in industrial fields are briefly reviewed and possible developments of CRB in the future are also described. PMID:27877949

  12. Progress in cold roll bonding of metals.

    PubMed

    Li, Long; Nagai, Kotobu; Yin, Fuxing

    2008-04-01

    Layered composite materials have become an increasingly interesting topic in industrial development. Cold roll bonding (CRB), as a solid phase method of bonding same or different metals by rolling at room temperature, has been widely used in manufacturing large layered composite sheets and foils. In this paper, we provide a brief overview of a technology using layered composite materials produced by CRB and discuss the suitability of this technology in the fabrication of layered composite materials. The effects of process parameters on bonding, mainly including process and surface preparation conditions, have been analyzed. Bonding between two sheets can be realized when deformation reduction reaches a threshold value. However, it is essential to remove surface contamination layers to produce a satisfactory bond in CRB. It has been suggested that the degreasing and then scratch brushing of surfaces create a strong bonding between the layers. Bonding mechanisms, in which the film theory is expressed as the major mechanism in CRB, as well as bonding theoretical models, have also been reviewed. It has also been showed that it is easy for bcc structure metals to bond compared with fcc and hcp structure metals. In addition, hardness on bonding same metals plays an important part in CRB. Applications of composites produced by CRB in industrial fields are briefly reviewed and possible developments of CRB in the future are also described.

  13. Precision instrumentation for rolling element bearing characterization.

    PubMed

    Marsh, Eric R; Vigliano, Vincent C; Weiss, Jeffrey R; Moerlein, Alex W; Vallance, R Ryan

    2007-03-01

    This article describes an instrument to measure the error motion of rolling element bearings. This challenge is met by simultaneously satisfying four requirements. First, an axial preload must be applied to seat the rolling elements in the bearing races. Second, one of the races must spin under the influence of an applied torque. Third, rotation of the remaining race must be prevented in a way that leaves the radial, axial/face, and tilt displacements free to move. Finally, the bearing must be fixtured and measured without introducing off-axis loading or other distorting influences. In the design presented here, an air bearing reference spindle with error motion of less than 10 nm rotates the inner race of the bearing under test. Noninfluencing couplings are used to prevent rotation of the bearing outer race and apply an axial preload without distorting the bearing or influencing the measurement. Capacitive displacement sensors with 2 nm resolution target the nonrotating outer race. The error motion measurement repeatability is shown to be less than 25 nm. The article closes with a discussion of how the instrument may be used to gather data with sufficient resolution to accurately estimate the contact angle of deep groove ball bearings.

  14. Precision instrumentation for rolling element bearing characterization

    SciTech Connect

    Marsh, Eric R.; Vigliano, Vincent C.; Weiss, Jeffrey R.; Moerlein, Alex W.; Vallance, R. Ryan

    2007-03-15

    This article describes an instrument to measure the error motion of rolling element bearings. This challenge is met by simultaneously satisfying four requirements. First, an axial preload must be applied to seat the rolling elements in the bearing races. Second, one of the races must spin under the influence of an applied torque. Third, rotation of the remaining race must be prevented in a way that leaves the radial, axial/face, and tilt displacements free to move. Finally, the bearing must be fixtured and measured without introducing off-axis loading or other distorting influences. In the design presented here, an air bearing reference spindle with error motion of less than 10 nm rotates the inner race of the bearing under test. Noninfluencing couplings are used to prevent rotation of the bearing outer race and apply an axial preload without distorting the bearing or influencing the measurement. Capacitive displacement sensors with 2 nm resolution target the nonrotating outer race. The error motion measurement repeatability is shown to be less than 25 nm. The article closes with a discussion of how the instrument may be used to gather data with sufficient resolution to accurately estimate the contact angle of deep groove ball bearings.

  15. Helicopter roll control effectiveness criteria program summary

    NASA Technical Reports Server (NTRS)

    Heffley, Robert K.; Bourne, Simon M.; Mnich, Marc A.

    1988-01-01

    A study of helicopter roll control effectiveness is summarized for the purpose of defining military helicopter handling qualities requirements. The study is based on an analysis of pilot-in-the-loop task performance of several basic maneuvers. This is extended by a series of piloted simulations using the NASA Ames Vertical Motion Simulator and selected flight data. The main results cover roll control power and short-term response characteristics. In general the handling qualities requirements recommended are set in conjunction with desired levels of flight task and maneuver response which can be directly observed in actual flight. An important aspect of this, however, is that vehicle handling qualities need to be set with regard to some quantitative aspect of mission performance. Specific examples of how this can be accomplished include a lateral unmask/remask maneuver in the presence of a threat and an air tracking maneuver which recognizes the kill probability enhancement connected with decreasing the range to the target. Conclusions and recommendations address not only the handling qualities recommendations, but also the general use of flight simulators and the dependence of mission performance on handling qualities.

  16. Rail roughness and rolling noise in tramways

    NASA Astrophysics Data System (ADS)

    Chiacchiari, L.; Thompson, DJ; Squicciarini, G.; Ntotsios, E.; Loprencipe, G.

    2016-09-01

    Companies which manage railway networks have to cope continually with the problem of operating safety and maintenance intervention issues related to rail surface irregularities. A lot of experience has been gained in recent years in railway applications but the case of tramways is quite different; in this field there are no specific criteria to define any intervention on rail surface restoration. This paper shows measurements carried out on some stretches of a tram network with the CAT equipment (Corrugation Analysis Trolley) for the principal purpose of detecting different states of degradation of the rails and identifying a level of deterioration to be associated with the need for maintenance through rail grinding. The measured roughness is used as an input parameter into prediction models for both rolling noise and ground vibration to show the potential effect that high levels of roughness can have in urban environment. Rolling noise predictions are also compared with noise measurements to illustrate the applicability of the modelling approach. Particular attention is given to the way the contact filter needs to be modelled in the specific case of trams that generally operate at low speed. Finally an empirical approach to assess vibration levels in buildings is presented.

  17. Terminal retrograde turn of rolling rings

    NASA Astrophysics Data System (ADS)

    Jalali, Mir Abbas; Sarebangholi, Milad S.; Alam, Mohammad-Reza

    2015-09-01

    We report an unexpected reverse spiral turn in the final stage of the motion of rolling rings. It is well known that spinning disks rotate in the same direction of their initial spin until they stop. While a spinning ring starts its motion with a kinematics similar to disks, i.e., moving along a cycloidal path prograde with the direction of its rigid body rotation, the mean trajectory of its center of mass later develops an inflection point so that the ring makes a spiral turn and revolves in a retrograde direction around a new center. Using high speed imaging and numerical simulations of models featuring a rolling rigid body, we show that the hollow geometry of a ring tunes the rotational air drag resistance so that the frictional force at the contact point with the ground changes its direction at the inflection point and puts the ring on a retrograde spiral trajectory. Our findings have potential applications in designing topologically new surface-effect flying objects capable of performing complex reorientation and translational maneuvers.

  18. Multi-hundred kilowatt roll ring assembly

    NASA Technical Reports Server (NTRS)

    Jacobson, Peter E.

    1985-01-01

    A program was completed to develop an evaluation unit of a high power rotary transfer device for potential application in a space environment. This device was configured around a Roll Ring concept which performs the same function as a slip ring/brush assembly with a rolling instead of sliding interface. An eight circuit Evaluation Unit (EU) and a portable Test Fixture (TF) were designed and fabricated. The EU was designed to transfer currents to 200 amperes at a potential of as high as 500 volts for an ultimate 100 kW/circuit transfer capability. The EU was evaluated in vacuum at dc transfer currents of 50 to 200 amperes at voltages to 10 volts and at 500 volts at 2 amperes. Power transfer to levels of 2 kW through each of the eight circuits was completed. Power transfer in vacuum at levels and efficiencies not previously achieved was demonstrated. The terminal-to-terminal resistance was measured to be greater than 0.42 milliohms which translates to an efficiency at 100 kW of 99.98 percent. The EU and TF have been delivered to the Lewis Research Center and are being prepared tor testing at increased power levels and for life testing, which will include both dc and ac power.

  19. Study of Titanium Alloy Sheet During H-sectioned Rolling Forming Using the Taguchi Method

    SciTech Connect

    Chen, D.-C.; Gu, W.-S.; Hwang, Y.-M.

    2007-05-17

    This study employs commercial DEFORM three-dimensional finite element code to investigate the plastic deformation behavior of Ti-6Al-4V titanium alloy sheet during the H-sectioned rolling process. The simulations are based on a rigid-plastic model and assume that the upper and lower rolls are rigid bodies and that the temperature rise induced during rolling is sufficiently small that it can be ignored. The effects of the roll profile, the friction factor between the rolls and the titanium alloy, the rolling temperature and the roll radii on the rolling force, the roll torque and the effective strain induced in the rolled product are examined. The Taguchi method is employed to optimize the H-sectioned rolling process parameters. The results confirm the effectiveness of this robust design methodology in optimizing the H-sectioned rolling process parameters for the current Ti-6Al-4V titanium alloy.

  20. 40 CFR 426.30 - Applicability; description of the rolled glass manufacturing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... rolled glass manufacturing subcategory. 426.30 Section 426.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Rolled Glass Manufacturing Subcategory § 426.30 Applicability; description of the rolled...

  1. 40 CFR 426.30 - Applicability; description of the rolled glass manufacturing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... rolled glass manufacturing subcategory. 426.30 Section 426.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Rolled Glass Manufacturing Subcategory § 426.30 Applicability; description of the rolled...

  2. 77 FR 9869 - Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG (RRD) Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-21

    ... 39-15860 (74 FR 12086, March 23, 2009): Rolls-Royce Deutschland Ltd & Co KG (formerly BMW Rolls-Royce GmbH, formerly BMW Rolls-Royce Aero Engines): Docket No. FAA-2008-0224; Directorate Identifier...

  3. 10. VIEW OF THE INSTALLATION OF PLUTONIUM FABRICATION ROLLING MILL. ...

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

    10. VIEW OF THE INSTALLATION OF PLUTONIUM FABRICATION ROLLING MILL. THE MILL ROLLED INGOTS INTO SHEETS THAT WERE THEN CUT INTO CIRCLE BLANKS TO BE PASSED THROUGH THE CENTER LINE FOR PRESSING. (2/19/63) - Rocky Flats Plant, Plutonium Fabrication, Central section of Plant, Golden, Jefferson County, CO

  4. New detection method for rolling element and bearing defects

    NASA Technical Reports Server (NTRS)

    Burchill, R. F.; Frarey, J. L.

    1972-01-01

    Instrument for detecting defects in rolling elements of bearings is described. Detection depends on rate at which rolling elements impact defect and establishes envelope amplitude of ball resonant frequency. Block diagram of instrument is provided and results obtained in conducting tests are reported.

  5. Simulation and optimization of the cold roll-forming process

    NASA Astrophysics Data System (ADS)

    Sheu, Jinn-Jong

    2004-06-01

    In this paper, the cold roll-forming process of steel was simulated. The FEM model of rollers was built in the LS-DYNA software. There are six stands used in the cold-roll-forming process simulation. The frictions of the tools were determined by the comparison of the cold-roll-forming results and the simulation deformation. Many friction conditions were tested to approach the experimental results of the forming experiments. The blanks were pushed through the rollers in the roll-forming machine. While in the simulation, the rollers were running over the fixed-end blank instead of moving the materials. The resulted motion is the same but the boundary conditions were easier to specify and control. The rolling speeds in the simulation were higher to save the calculation time but still confirm to the experiment results. The simulation results shown the axial and the shear strains were induced during the bending process of sheet metal. The thickness of the sheet metal was varied very slightly during the roll-forming process. The dimension and shape of the cold roll-formed specimens were in good agreement with the experiment results. The Taguchi method was adopted to design an optimum roll flower.

  6. High-strength rolled sections with structural anisotropy

    NASA Astrophysics Data System (ADS)

    Odesskii, P. D.; Chernenko, V. T.

    1992-08-01

    The article investigates the properties of high-strength sections .for building structures. It examines theinfluence of structural anisotropy on the operational properties of profiles of steel St3ps strengthened fromthe rolling heat on a high-speed mill. It is shown that the use of such rolled sections in industo, is promising.

  7. 16. VIEW OF A ROLLING MILL THAT WAS USED TO ...

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

    16. VIEW OF A ROLLING MILL THAT WAS USED TO CREATE A METAL SHEET (SHOWN). (4/16/57) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  8. 5. VIEW OF BERYLLIUM PROCESSING AREA, ROLLING MILL. BERYLLIUM FORMING ...

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

    5. VIEW OF BERYLLIUM PROCESSING AREA, ROLLING MILL. BERYLLIUM FORMING BEGAN IN SIDE A OF THE BUILDING IN 1962. (11/5/73) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  9. Skimming the Surface: Teaching Kayak Support Strokes and Rolls.

    ERIC Educational Resources Information Center

    Higgins, Peter; Morgan, Alastair

    1997-01-01

    Teaching novice kayakers only the biomechanics of a roll and other "closed" (nonadaptable) skills does not create opportunities for flexible skill development. A wider approach teaches support strokes and rolls by focusing on "open" skills that can be transferred or adapted to any situation, including emergency decision making,…

  10. Effect of Flaw Removal on Billets in Rolling

    NASA Astrophysics Data System (ADS)

    Yoshida, Kazunari; Shinohara, Tetsuo

    2007-05-01

    High-quality wires, which are used for components such as valve springs of automobiles, are fabricated by rolling and drawing. Even a minute flaw on the surface of the wire leads to a significant decrease in fatigue strength. It is possible to decrease the number of surface flaws during some of the rolling processes; however in most cases, it is difficult to remove flaws. Under such circumstances, high-quality wires are fabricated, at many wire manufacturing factories, by rolling and drawing after removing surface flaws on the raw material. However, the flaw removal process is carried out relying on the experience of onsite workers; many of the mechanisms underlying flaw removal have not been clarified. In this study, billet and wire that have traces formed during flaw removal were subjected to rolling to investigate the behavior of deformation and the recovery of the flaw-removal traces. When flaw-removal traces exist on a billet surface that comes into contact with the roll used in rolling, the traces are removed without difficulty. However, when the flaw-removal traces exist on a surface that does not come into contact with the roll, the traces tend to become wrinkles due to compression from the upper and lower directions. Therefore, when removing the surface flaw on billet before rolling, it is important to remove flaw part thinly.

  11. 14 CFR 25.491 - Taxi, takeoff and landing roll.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., takeoff and landing roll. Within the range of appropriate ground speeds and approved weights, the airplane structure and landing gear are assumed to be subjected to loads not less than those obtained when the... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Taxi, takeoff and landing roll....

  12. 14 CFR 25.491 - Taxi, takeoff and landing roll.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., takeoff and landing roll. Within the range of appropriate ground speeds and approved weights, the airplane structure and landing gear are assumed to be subjected to loads not less than those obtained when the... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Taxi, takeoff and landing roll....

  13. Calendering and Rolling of Viscoplastic Materials: Theory and Experiments

    NASA Astrophysics Data System (ADS)

    Mitsoulis, E.; Sofou, S.; Muliawan, E. B.; Hatzikiriakos, S. G.

    2007-04-01

    The calendering and rolling processes are used in a wide variety of industries for the production of rolled sheets or films of specific thickness and final appearance. The acquired final sheet thickness depends mainly on the rheological properties of the material. Materials which have been used in the present study are foodstuff (such as mozzarella cheese and flour-water dough) used in food processing. These materials are rheologically viscoplastic, obeying the Herschel-Bulkley model. The results give the final sheet thickness and the torque as a function of the roll speed. Theoretical analysis based on the Lubrication Approximation Theory (LAT) shows that LAT is a good predictive tool for calendering, where the sheet thickness is very small compared with the roll size. However, in rolling where this is not true, LAT does not hold, and a 2-D analysis is necessary.

  14. Ground roll attenuation using non-stationary matching filtering

    NASA Astrophysics Data System (ADS)

    Jiao, Shebao; Chen, Yangkang; Bai, Min; Yang, Wencheng; Wang, Erying; Gan, Shuwei

    2015-12-01

    Conventional approaches based on adaptive subtraction for ground roll attenuation first predict an initial model for ground rolls and then adaptively subtract it from the original data using a stationary matching filter (MF). Because of the non-stationary property of seismic data and ground rolls, the application of a traditional stationary MF is not physically plausible. Thus, in the case of highly non-stationary seismic reflections and ground rolls, a stationary MF cannot obtain satisfactory results. In this paper, we apply a non-stationary matching filter (NMF) to adaptively subtract the ground rolls. The NMF can be obtained by solving a highly under-determined inversion problem using non-stationary autoregression. We apply the proposed approach to one synthetic example and two field data examples, and demonstrate a much improved performance compared with the traditional MF approach.

  15. Large transient fault current test of an electrical roll ring

    NASA Technical Reports Server (NTRS)

    Yenni, Edward J.; Birchenough, Arthur G.

    1992-01-01

    The space station uses precision rotary gimbals to provide for sun tracking of its photoelectric arrays. Electrical power, command signals and data are transferred across the gimbals by roll rings. Roll rings have been shown to be capable of highly efficient electrical transmission and long life, through tests conducted at the NASA Lewis Research Center and Honeywell's Satellite and Space Systems Division in Phoenix, AZ. Large potential fault currents inherent to the power system's DC distribution architecture, have brought about the need to evaluate the effects of large transient fault currents on roll rings. A test recently conducted at Lewis subjected a roll ring to a simulated worst case space station electrical fault. The system model used to obtain the fault profile is described, along with details of the reduced order circuit that was used to simulate the fault. Test results comparing roll ring performance before and after the fault are also presented.

  16. Rolling-contact deformation of MgO single crystals

    NASA Technical Reports Server (NTRS)

    Dufrane, K. F.; Glaeser, W. A.

    1976-01-01

    Magnesium oxide single crystals were used as a model bearing material and deformed by rolling contact with a steel ball 0.64 cm in diameter. A dependence of depth of slip on rolling velocity which persisted with increasing numbers of rolling-contact cycles was discovered. The track width, track hardness and dislocation interactions as observed by transmission electron microscopy all increased in a consistent manner with increasing cycles. The rolling-contact state of stress produces a high density of dislocations in a localized zone. Dislocation interaction in this zone produces cleavage-type cracks after a large number of rolling-contact cycles. The orientation of the crystal influences the character of dislocation accumulation.

  17. Compressibility of tungsten and molybdenum bars during rotary swaging and rolling

    NASA Astrophysics Data System (ADS)

    Barkov, L. A.; Mymrin, S. A.; Samodurova, M. N.; Dzhigun, N. S.; Latfulina, Yu. S.

    2015-05-01

    The compressibility of bars and hydraulically forged workpieces made of tungsten and molybdenum is studied during rotary swaging and rolling in mills with two-, three-, and four-roll passes. The compressibility of molybdenum MCh bars and hydraulically forged molybdenum M-MP workpieces is investigated during rotary swaging and rolling in three- and four-roll passes. The compressibility of tungsten VA and VL bars and hydraulically forged tungsten V-MP workpieces is investigated during rotary swaging and rolling in three- and four-roll passes. The compressibility of the hydraulically forged tungsten V-MP workpieces is analyzed under two- and four-roll pass rolling conditions.

  18. Effect of Rolling Massage on the Vortex Flow in Blood Vessels with Lattice Boltzmann Simulation

    NASA Astrophysics Data System (ADS)

    Yi, Hou Hui

    The rolling massage manipulation is a classic Chinese Medical Massage, which is a nature therapy in eliminating many diseases. Here, the effect of the rolling massage on the cavity flows in blood vessel under the rolling manipulation is studied by the lattice Boltzmann simulation. The simulation results show that the vortex flows are fully disturbed by the rolling massage. The flow behavior depends on the rolling velocity and the rolling depth. Rolling massage has a better effect on the flows in the cavity than that of the flows in a planar blood vessel. The result is helpful to understand the mechanism of the massage and develop the rolling techniques.

  19. Effective parameters in ground roll attenuation using FO CRS stacking

    NASA Astrophysics Data System (ADS)

    Rastegar, Seyyed Ali Fa'al; Javaherian, Abdolrahim; Farajkhah, Naser Keshavarz; Monfared, Mehrdad Soleimani; Zarei, Abbas

    2016-12-01

    Ground roll is a coherent noise in land seismic data that has high energy, high amplitude, low frequency and low velocity. It has to be attenuated in the seismic data processing as it may mask reflections in the zone of ground roll. In this study, we employed common reflection surface for finite offset (FO CRS) to attenuate the ground roll. The FO CRS stacking operator is a hyperbola; therefore, it fits the hyperbolic reflections in the prestack data. Conversely, the ground roll is linear in the common-midpoint (CMP) and common-shot (CS) gathers and can be distinguished and attenuated by the FO CRS operator. Thus, we search for the dip and curvature of the reflections in the CMP section and CS gather prior to the finite-offset section. When the algorithm is specified, the ground roll and reflections have low and high coherency values, respectively. So, any event with non-hyperbolic traveltime, like the linear traveltime ground roll can be removed. We applied the proposed method on a synthetic and an oilfield data from the west of Iran. Results showed that the FO CRS stacking method properly attenuated the ground roll. Further investigations were the effects of spatial aliasing, frequency content, random noise, ground roll dip, the range of dip and curvature scans and reflection amplitudes on ground roll attenuation by the FO CRS stacking. From mentioned parameters, spatial aliasing, frequency content, and random noise had no significant effects. On the contrary, the proposed method turned out to be strongly dependent upon ground roll dip, the range of dip and curvature scans and reflection amplitudes.

  20. Foam Rolling of Quadriceps Decreases Biceps Femoris Activation.

    PubMed

    Cavanaugh, Mark Tyler; Aboodarda, Saied Jalal; Hodgson, Daniel; Behm, David George

    2016-09-06

    Foam rolling has been shown to increase range of motion without subsequent performance impairments of the rolled muscle, however, there are no studies examining rolling effects on antagonist muscles. The objective of this study was to determine whether foam rolling the hamstrings and/or quadriceps would affect hamstrings and quadriceps activation in men and women. Recreationally active men (n=10, 25 ± 4.6 years, 180.1 ± 4.4 cm, 86.5 ± 15.7 kg) and women (n=8, 21.75 ± 3.2 years, 166.4 ± 8.8 cm, 58.9 ± 7.9 kg) had surface electromyographic activity analyzed in the dominant vastus lateralis (VL), vastus medialis (VM), and biceps femoris (BF) muscles upon a single leg landing from a hurdle jump under four conditions. Conditions included rolling of the hamstrings, quadriceps, both muscle groups and a control session. BF activation significantly decreased following quadriceps foam rolling (F(1,16) = 7.45, p = 0.015, -8.9%). There were no significant changes in quadriceps activation following hamstrings foam rolling. This might be attributed to the significantly greater levels of perceived pain with quadriceps rolling applications (F(1,18) = 39.067, p < 0.001, 98.2%). There were no sex-based changes in activation following foam rolling for VL (F(6,30) = 1.31, p = 0.283) VM (F(6,30) = 1.203, p = 0.332) or BF (F(6,36) = 1.703, p = 0.199). Antagonist muscle activation may be altered following agonist foam rolling, however, it can be suggested that any changes in activation are likely a result of reciprocal inhibition due to increased agonist pain perception.

  1. Truck Roll Stability Data Collection and Analysis

    SciTech Connect

    Stevens, SS

    2001-07-02

    The principal objective of this project was to collect and analyze vehicle and highway data that are relevant to the problem of truck rollover crashes, and in particular to the subset of rollover crashes that are caused by the driver error of entering a curve at a speed too great to allow safe completion of the turn. The data are of two sorts--vehicle dynamic performance data, and highway geometry data as revealed by vehicle behavior in normal driving. Vehicle dynamic performance data are relevant because the roll stability of a tractor trailer depends both on inherent physical characteristics of the vehicle and on the weight and distribution of the particular cargo that is being carried. Highway geometric data are relevant because the set of crashes of primary interest to this study are caused by lateral acceleration demand in a curve that exceeds the instantaneous roll stability of the vehicle. An analysis of data quality requires an evaluation of the equipment used to collect the data because the reliability and accuracy of both the equipment and the data could profoundly affect the safety of the driver and other highway users. Therefore, a concomitant objective was an evaluation of the performance of the set of data-collection equipment on the truck and trailer. The objective concerning evaluation of the equipment was accomplished, but the results were not entirely positive. Significant engineering apparently remains to be done before a reliable system can be fielded. Problems were identified with the trailer to tractor fiber optic connector used for this test. In an over-the-road environment, the communication between the trailer instrumentation and the tractor must be dependable. In addition, the computer in the truck must be able to withstand the rigors of the road. The major objective--data collection and analysis--was also accomplished. Using data collected by instruments on the truck, a ''bad-curve'' database can be generated. Using this database

  2. Flexure-based Roll-to-roll Platform: A Practical Solution for Realizing Large-area Microcontact Printing

    PubMed Central

    Zhou, Xi; Xu, Huihua; Cheng, Jiyi; Zhao, Ni; Chen, Shih-Chi

    2015-01-01

    A continuous roll-to-roll microcontact printing (MCP) platform promises large-area nanoscale patterning with significantly improved throughput and a great variety of applications, e.g. precision patterning of metals, bio-molecules, colloidal nanocrystals, etc. Compared with nanoimprint lithography, MCP does not require a thermal imprinting step (which limits the speed and material choices), but instead, extreme precision with multi-axis positioning and misalignment correction capabilities for large area adaptation. In this work, we exploit a flexure-based mechanism that enables continuous MCP with 500 nm precision and 0.05 N force control. The fully automated roll-to-roll platform is coupled with a new backfilling MCP chemistry optimized for high-speed patterning of gold and silver. Gratings of 300, 400, 600 nm line-width at various locations on a 4-inch plastic substrate are fabricated at a speed of 60 cm/min. Our work represents the first example of roll-to-roll MCP with high reproducibility, wafer scale production capability at nanometer resolution. The precision roll-to-roll platform can be readily applied to other material systems. PMID:26037147

  3. Planarization coating for polyimide substrates used in roll-to-roll fabrication of active matrix backplanes for flexible displays

    NASA Astrophysics Data System (ADS)

    Almanza-Workman, A. Marcia; Jeans, Albert; Braymen, Steve; Elder, Richard E.; Garcia, Robert A.; de la Fuente Vornbrock, Alejandro; Hauschildt, Jason; Holland, Edward; Jackson, Warren; Jam, Mehrban; Jeffrey, Frank; Junge, Kelly; Kim, Han-Jun; Kwon, Ohseung; Larson, Don; Luo, Hao; Maltabes, John; Mei, Ping; Perlov, Craig; Smith, Mark; Stieler, Dan; Taussig, Carl P.; Trovinger, Steve; Zhao, Lihua

    2012-03-01

    Good surface quality of plastic substrates is essential to reduce pixel defects during roll-to-roll fabrication of flexible display active matrix backplanes. Standard polyimide substrates have a high density of "bumps" from fillers and belt marks and other defects from dust and surface scratching. Some of these defects could be the source of shunts in dielectrics. The gate dielectric must prevent shorts between the source/drain and the gate in the transistors, resist shorts in the hold capacitor and stop shorts in the data/gate line crossovers in active matrix backplanes fabricated by self-aligned imprint lithography (SAIL) roll-to-roll processes. Otherwise data and gate lines will become shorted creating line or pixel defects. In this paper, we discuss the development of a proprietary UV curable planarization material that can be coated by roll-to-roll processes. This material was engineered to have low shrinkage, excellent adhesion to polyimide, high dry etch resistance, and great chemical and thermal stability. Results from PECVD deposition of an amorphous silicon stack on the planarized polyimide and compatibility with roll-to-roll processes to fabricate active matrix backplanes are also discussed. The effect of the planarization on defects in the stack, shunts in the dielectric and curvature of finished arrays will also be described.

  4. Noncontact conductivity and dielectric measurement for high throughput roll-to-roll nanomanufacturing

    NASA Astrophysics Data System (ADS)

    Orloff, Nathan D.; Long, Christian J.; Obrzut, Jan; Maillaud, Laurent; Mirri, Francesca; Kole, Thomas P.; McMichael, Robert D.; Pasquali, Matteo; Stranick, Stephan J.; Alexander Liddle, J.

    2015-11-01

    Advances in roll-to-roll processing of graphene and carbon nanotubes have at last led to the continuous production of high-quality coatings and filaments, ushering in a wave of applications for flexible and wearable electronics, woven fabrics, and wires. These applications often require specific electrical properties, and hence precise control over material micro- and nanostructure. While such control can be achieved, in principle, by closed-loop processing methods, there are relatively few noncontact and nondestructive options for quantifying the electrical properties of materials on a moving web at the speed required in modern nanomanufacturing. Here, we demonstrate a noncontact microwave method for measuring the dielectric constant and conductivity (or geometry for samples of known dielectric properties) of materials in a millisecond. Such measurement times are compatible with current and future industrial needs, enabling real-time materials characterization and in-line control of processing variables without disrupting production.

  5. Roll-to-Roll Production of Spray Coated N-doped Carbon Nanotube Electrodes for Supercapacitors

    NASA Astrophysics Data System (ADS)

    Karakaya, Mehmet; Zhu, Jingyi; Raghavendra, Achyut; Podila, Ramakrishna; Parler, Samuel; Kaplan, James; Rao, Apparao; Cornell Dubilier Electronics, Inc. Collaboration

    2015-03-01

    Although nanocarbons are being increasingly used in energy storage, there has been a lack of inexpensive, continuous and scalable synthesis methods. Here we present a scalable roll-to-roll spray coating process for synthesizing supercapacitors from randomly oriented multi-walled carbon nanotubes electrodes on Al foils, which yield high power and energy densities (~ 700 mW/cm3 and 1 mWh/cm3) and cycle stability (>10000 cycles) on par with Li-ion thin film batteries. Our cost analysis shows that the R2R spray coating process can produce supercapacitors with 10 times the energy density of conventional activated carbon devices at ~ 17% lower cost. NSF CMMI SNM Award #1246800.

  6. Noncontact conductivity and dielectric measurement for high throughput roll-to-roll nanomanufacturing

    PubMed Central

    Orloff, Nathan D.; Long, Christian J.; Obrzut, Jan; Maillaud, Laurent; Mirri, Francesca; Kole, Thomas P.; McMichael, Robert D.; Pasquali, Matteo; Stranick, Stephan J.; Alexander Liddle, J.

    2015-01-01

    Advances in roll-to-roll processing of graphene and carbon nanotubes have at last led to the continuous production of high-quality coatings and filaments, ushering in a wave of applications for flexible and wearable electronics, woven fabrics, and wires. These applications often require specific electrical properties, and hence precise control over material micro- and nanostructure. While such control can be achieved, in principle, by closed-loop processing methods, there are relatively few noncontact and nondestructive options for quantifying the electrical properties of materials on a moving web at the speed required in modern nanomanufacturing. Here, we demonstrate a noncontact microwave method for measuring the dielectric constant and conductivity (or geometry for samples of known dielectric properties) of materials in a millisecond. Such measurement times are compatible with current and future industrial needs, enabling real-time materials characterization and in-line control of processing variables without disrupting production. PMID:26592441

  7. Roll-to-roll anodization and etching of aluminum foils for high-throughput surface nanotexturing.

    PubMed

    Lee, Min Hyung; Lim, Namsoo; Ruebusch, Daniel J; Jamshidi, Arash; Kapadia, Rehan; Lee, Rebecca; Seok, Tae Joon; Takei, Kuniharu; Cho, Kee Young; Fan, Zhiyoung; Jang, Hwanung; Wu, Ming; Cho, Gyoujin; Javey, Ali

    2011-08-10

    A high-throughput process for nanotexturing of hard and soft surfaces based on the roll-to-roll anodization and etching of low-cost aluminum foils is presented. The process enables the precise control of surface topography, feature size, and shape over large areas thereby presenting a highly versatile platform for fabricating substrates with user-defined, functional performance. Specifically, the optical and surface wetting properties of the foil substrates were systematically characterized and tuned through the modulation of the surface texture. In addition, textured aluminum foils with pore and bowl surface features were used as zeptoliter reaction vessels for the well-controlled synthesis of inorganic, organic, and plasmonic nanomaterials, demonstrating yet another powerful potential use of the presented approach.

  8. Growth of continuous graphene by open roll-to-roll chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Zhong, Guofang; Wu, Xingyi; D'Arsie, Lorenzo; Teo, Kenneth B. K.; Rupesinghe, Nalin L.; Jouvray, Alex; Robertson, John

    2016-11-01

    We demonstrate the growth of high-quality, continuous monolayer graphene on Cu foils using an open roll-to-roll (R2R) chemical vapor deposition (CVD) reactor with both static and moving foil growth conditions. N2 instead of Ar was used as carrier gas to reduce process cost, and the concentrations of H2 and CH4 reactants were kept below the lower explosive limit to ensure process safety for reactor ends open to ambient. The carrier mobility of graphene deposited at a Cu foil winding speed of 5 mm/min was 5270-6040 cm2 V-1 s-1 at room temperature (on 50 μm × 50 μm Hall devices). These results will enable the inline integration of graphene CVD for industrial R2R production.

  9. Thermoresistive strain sensor and positioning method for roll-to-roll processes.

    PubMed

    Liao, Kuan-Hsun; Lo, Cheng-Yao

    2014-05-05

    This study uses the Joule heating effect-generated temperature difference to monitor in real-time and localize both compressive and tensile strains for the polymer substrates used in the roll-to-roll process. A serpentine gold (Au) line was patterned on a polyethylenenaphthalate (PEN) substrate to form the strain sensor based on thermoresistive behavior. This strain sensor was then subjected to either current or voltage to induce the Joule heating effect on the Au resistor. An infrared (IR) detector was used to monitor the strain-induced temperature difference on the Au and PEN surfaces and the minimal detectable bending radius was 0.9 mm with a gauge factor (GF) of 1.46. The proposed design eliminates the judgment ambiguity from conventional resistive strain sensors where resistance is the only physical quantity monitored. This study precisely and successfully indicated the local strain quantitatively and qualitatively with complete simulations and measurements.

  10. Cotton-textile-enabled flexible self-sustaining power packs via roll-to-roll fabrication.

    PubMed

    Gao, Zan; Bumgardner, Clifton; Song, Ningning; Zhang, Yunya; Li, Jingjing; Li, Xiaodong

    2016-05-18

    With rising energy concerns, efficient energy conversion and storage devices are required to provide a sustainable, green energy supply. Solar cells hold promise as energy conversion devices due to their utilization of readily accessible solar energy; however, the output of solar cells can be non-continuous and unstable. Therefore, it is necessary to combine solar cells with compatible energy storage devices to realize a stable power supply. To this end, supercapacitors, highly efficient energy storage devices, can be integrated with solar cells to mitigate the power fluctuations. Here, we report on the development of a solar cell-supercapacitor hybrid device as a solution to this energy requirement. A high-performance, cotton-textile-enabled asymmetric supercapacitor is integrated with a flexible solar cell via a scalable roll-to-roll manufacturing approach to fabricate a self-sustaining power pack, demonstrating its potential to continuously power future electronic devices.

  11. Investigation of pattern transfer to piezoelectric jetted polymer using roll-to-roll nanoimprint lithography

    NASA Astrophysics Data System (ADS)

    Menezes, Shannon John

    Nanoimprint Lithography (NIL) has existed since the mid 1990s as a proven concept of creating micro- and nanostructures using direct mechanical pattern transfer. Initially seen as a viable option to replace conventional lithography methods, the lack of technology to support large-scale manufacturing using NIL has motivated researchers to explore the application of NIL to create a better, more cost-efficient process with the ability to integrate NIL into a mass manufacturing system. One such method is the roll-to-roll process, similar to that used in printing presses of newspapers and plastics. This thesis is an investigation to characterize polymer deposition using a piezoelectric jetting head and attempt to create micro- and nanostructures on the polymer using R2RNIL technique.

  12. Roll-to-roll fabrication and metastability in metal oxide transistors

    NASA Astrophysics Data System (ADS)

    Jackson, Warren B.; Kim, Han-Jun; Kwon, Ohseung; Yeh, Bao; Hoffman, Randy; Mourey, Devin; Koch, Tim; Taussig, Carl; Elder, Richard; Jeans, Albert

    2011-03-01

    A roll-to-roll process is used to fabricate amorphous silicon and amorphous multicomponent oxide (MCO) transistors on flexible substrates using self aligned imprint lithography (SAIL). SAIL solves the layer to layer alignment problem. The imprint lithography patterned MCO transistors had a mobility of 15 cm2V-1 sec-1 and an on-off ratio of 107. Full display arrays with data, gate, hold capacitors and cross-overs were patterned using SAIL technology. Studies of stability of the MCO transistors indicate the importance of controlling O vacancies in the material particularly the back channel. Devices subjected to -10V gate bias stress at 60C under illumination exhibited behavior consistent with state creation in the upper and lower half of the gap near the back channel interface possibly associated with O vacancy formation.

  13. Cotton-textile-enabled flexible self-sustaining power packs via roll-to-roll fabrication

    NASA Astrophysics Data System (ADS)

    Gao, Zan; Bumgardner, Clifton; Song, Ningning; Zhang, Yunya; Li, Jingjing; Li, Xiaodong

    2016-05-01

    With rising energy concerns, efficient energy conversion and storage devices are required to provide a sustainable, green energy supply. Solar cells hold promise as energy conversion devices due to their utilization of readily accessible solar energy; however, the output of solar cells can be non-continuous and unstable. Therefore, it is necessary to combine solar cells with compatible energy storage devices to realize a stable power supply. To this end, supercapacitors, highly efficient energy storage devices, can be integrated with solar cells to mitigate the power fluctuations. Here, we report on the development of a solar cell-supercapacitor hybrid device as a solution to this energy requirement. A high-performance, cotton-textile-enabled asymmetric supercapacitor is integrated with a flexible solar cell via a scalable roll-to-roll manufacturing approach to fabricate a self-sustaining power pack, demonstrating its potential to continuously power future electronic devices.

  14. Cotton-textile-enabled flexible self-sustaining power packs via roll-to-roll fabrication

    PubMed Central

    Gao, Zan; Bumgardner, Clifton; Song, Ningning; Zhang, Yunya; Li, Jingjing; Li, Xiaodong

    2016-01-01

    With rising energy concerns, efficient energy conversion and storage devices are required to provide a sustainable, green energy supply. Solar cells hold promise as energy conversion devices due to their utilization of readily accessible solar energy; however, the output of solar cells can be non-continuous and unstable. Therefore, it is necessary to combine solar cells with compatible energy storage devices to realize a stable power supply. To this end, supercapacitors, highly efficient energy storage devices, can be integrated with solar cells to mitigate the power fluctuations. Here, we report on the development of a solar cell-supercapacitor hybrid device as a solution to this energy requirement. A high-performance, cotton-textile-enabled asymmetric supercapacitor is integrated with a flexible solar cell via a scalable roll-to-roll manufacturing approach to fabricate a self-sustaining power pack, demonstrating its potential to continuously power future electronic devices. PMID:27189776

  15. Noncontact conductivity and dielectric measurement for high throughput roll-to-roll nanomanufacturing.

    PubMed

    Orloff, Nathan D; Long, Christian J; Obrzut, Jan; Maillaud, Laurent; Mirri, Francesca; Kole, Thomas P; McMichael, Robert D; Pasquali, Matteo; Stranick, Stephan J; Liddle, J Alexander

    2015-11-23

    Advances in roll-to-roll processing of graphene and carbon nanotubes have at last led to the continuous production of high-quality coatings and filaments, ushering in a wave of applications for flexible and wearable electronics, woven fabrics, and wires. These applications often require specific electrical properties, and hence precise control over material micro- and nanostructure. While such control can be achieved, in principle, by closed-loop processing methods, there are relatively few noncontact and nondestructive options for quantifying the electrical properties of materials on a moving web at the speed required in modern nanomanufacturing. Here, we demonstrate a noncontact microwave method for measuring the dielectric constant and conductivity (or geometry for samples of known dielectric properties) of materials in a millisecond. Such measurement times are compatible with current and future industrial needs, enabling real-time materials characterization and in-line control of processing variables without disrupting production.

  16. Thermoresistive Strain Sensor and Positioning Method for Roll-to-Roll Processes

    PubMed Central

    Liao, Kuan-Hsun; Lo, Cheng-Yao

    2014-01-01

    This study uses the Joule heating effect-generated temperature difference to monitor in real-time and localize both compressive and tensile strains for the polymer substrates used in the roll-to-roll process. A serpentine gold (Au) line was patterned on a polyethylenenaphthalate (PEN) substrate to form the strain sensor based on thermoresistive behavior. This strain sensor was then subjected to either current or voltage to induce the Joule heating effect on the Au resistor. An infrared (IR) detector was used to monitor the strain-induced temperature difference on the Au and PEN surfaces and the minimal detectable bending radius was 0.9 mm with a gauge factor (GF) of 1.46. The proposed design eliminates the judgment ambiguity from conventional resistive strain sensors where resistance is the only physical quantity monitored. This study precisely and successfully indicated the local strain quantitatively and qualitatively with complete simulations and measurements. PMID:24803196

  17. Roll up nanowire battery from silicon chips.

    PubMed

    Vlad, Alexandru; Reddy, Arava Leela Mohana; Ajayan, Anakha; Singh, Neelam; Gohy, Jean-François; Melinte, Sorin; Ajayan, Pulickel M

    2012-09-18

    Here we report an approach to roll out Li-ion battery components from silicon chips by a continuous and repeatable etch-infiltrate-peel cycle. Vertically aligned silicon nanowires etched from recycled silicon wafers are captured in a polymer matrix that operates as Li(+) gel-electrolyte and electrode separator and peeled off to make multiple battery devices out of a single wafer. Porous, electrically interconnected copper nanoshells are conformally deposited around the silicon nanowires to stabilize the electrodes over extended cycles and provide efficient current collection. Using the above developed process we demonstrate an operational full cell 3.4 V lithium-polymer silicon nanowire (LIPOSIL) battery which is mechanically flexible and scalable to large dimensions.

  18. Mars aerocapture using continuous roll techniques

    NASA Astrophysics Data System (ADS)

    Willcockson, W. H.

    1992-08-01

    Capture of a Mars vehicle into a closed orbit can benefit greatly from the use of aerodynamic deceleration (Aerocapture). Because of the unknowns associated with the Mars environment, the use of adaptive control techniques is critical to the successful outcome. This paper will describe work done over several years at assessing the performance of a continuous roll control technique coupled with a closed loop predictor corrector guidance system. The implementation of this system is called CLAAS (Closed Loop AeroAssist Simulation). This system has been tested against a variety of dispersions including a variety of atmospheric models, atmospheric shear waves, vehicle variations, and navigation errors. Results will be shown for a two mission applications, a representative manned Mars vehicle and an unmanned Mars Rover Sample Return (MRSR) system. Finally, a few observations on technical challenges for aerobraking a Mars vehicle are included in the conclusions.

  19. Rolling element fatigue testing of gear materials

    NASA Technical Reports Server (NTRS)

    Nahm, A. H.

    1978-01-01

    Rolling element fatigue lives of eleven alloys were evaluated. The eleven alloys studied were three nitriding alloys (Super Nitralloy, Nitralloy 135, and Nitralloy N), four case carburizing alloys (AISI 9310, CBS 600, CBS 1000M and Vasco X-2), and four throughhardening alloys (Vasco Matrix II,AISI W-1, AISI S-2 and AISI O-2). Several different heat treatments and/or melting processes were studied on the three carburizing alloy steels. Metallurgical analyses were made before and after the RC rig tests. Test data were statistically analyzed using the Weibull distribution function. B-10 lives were compared versus VIM-VAR AISI M-50 and carburized VAR AISI 9310, as reference alloys.

  20. Controlled Microwave Heating Accelerates Rolling Circle Amplification.

    PubMed

    Yoshimura, Takeo; Suzuki, Takamasa; Mineki, Shigeru; Ohuchi, Shokichi

    2015-01-01

    Rolling circle amplification (RCA) generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.

  1. Roll up nanowire battery from silicon chips

    PubMed Central

    Vlad, Alexandru; Reddy, Arava Leela Mohana; Ajayan, Anakha; Singh, Neelam; Gohy, Jean-François; Melinte, Sorin; Ajayan, Pulickel M.

    2012-01-01

    Here we report an approach to roll out Li-ion battery components from silicon chips by a continuous and repeatable etch-infiltrate-peel cycle. Vertically aligned silicon nanowires etched from recycled silicon wafers are captured in a polymer matrix that operates as Li+ gel-electrolyte and electrode separator and peeled off to make multiple battery devices out of a single wafer. Porous, electrically interconnected copper nanoshells are conformally deposited around the silicon nanowires to stabilize the electrodes over extended cycles and provide efficient current collection. Using the above developed process we demonstrate an operational full cell 3.4 V lithium-polymer silicon nanowire (LIPOSIL) battery which is mechanically flexible and scalable to large dimensions. PMID:22949696

  2. Fatigue and material response in rolling contact

    SciTech Connect

    Voskamp, A.P.

    1998-12-31

    Metal softening, induced during the so-called third stage of material response to rolling contact loading, increases the probability of spalling fatigue failure. Metal softening in the most heavily loaded subsurface region leads to micro-plastic deformation noticeable from the occurrence of microstructural change. The probability of crack initiation increases with the growth of the plastically deformed subsurface region. Subsequent crack growth in that region is stimulated by the induced residual stress and texture. Fatigue failure in modern clean bearing steel develops only when the material has reached the third stage. The threshold to the third stage can be determined, and thus fatigue life can be assessed from observations of microstructural change. Examples are discussed of observed reduction of the ferrite (211) diffraction-line width in relation to observed endurance.

  3. Modeling of rolling element bearing mechanics

    NASA Technical Reports Server (NTRS)

    Greenhill, L. M.

    1991-01-01

    Roller element bearings provide the primary mechanical interface between rotating and nonrotating components in the high performance turbomachinery of the Space Shuttle Main Engine (SSME). Knowledge of bearing behavior under various loading and environmental conditions is essential to predicting and understanding the overall behavior of turbopumps, including rotordynamic stability, critical speeds and bearing life. The objective is to develop mathematical models and computer programs to describe the mechanical behavior of ball and cylinder roller bearings under the loading and environmental conditions encountered in the SSME and future high performance rocket engines. This includes characteristics such as nonlinear load/motion relationships, stiffness and damping, rolling element loads for life prediction, and roller and cage stability.

  4. Adaptive Prognostics for Rolling Element Bearing Condition

    NASA Astrophysics Data System (ADS)

    Li, Y.; Billington, S.; Zhang, C.; Kurfess, T.; Danyluk, S.; Liang, S.

    1999-01-01

    Rolling element bearing failure is one of the foremost causes of breakdown in rotating machinery. This paper proposes a remaining life adaptation methodology based on mechanistic modeling and parameter tuning. Vibration measurement is used to estimate defect severity by monitoring the signals generated from rotating bearings. Through a defect propagation model and defect diagnostic model, an adaptive algorithm is developed to fine tune the parameters involved in the propagation model by comparing predicted and measured defect sizes. In this manner, the instantaneous rate of defect propagation can be captured despite defect growth behavior variation. Therefore, a precise estimation of the remaining life can be determined. Simulations and experimental results are presented to illustrate the implementation principles and to verify the applicability of the adaptive prognostic methodology.

  5. STS-98 Atlantis rolls to the VAB

    NASA Technical Reports Server (NTRS)

    2001-01-01

    KENNEDY SPACE CENTER, Fla. -- Space Shuttle Atlantis moves past palm trees on its way back to the Vehicle Assembly Building from Launch Pad 39A. Atlantis is rolling back to the VAB from Launch Pad 39A. In the VAB workers will conduct inspections, make continuity checks and conduct X-ray analysis on the 36 solid rocket booster cables located inside each booster'''s external system tunnel. An extensive evaluation of NASA'''s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis before launching. The launch has been rescheduled no earlier than Feb. 6.

  6. Nanoscale precipitation in hot rolled sheet steel

    NASA Astrophysics Data System (ADS)

    Sun, Jun

    Some newer hot rolled high strength low alloy (HSLA) steels with a single phase ferrite matrix have obtained substantial strengthening from nanoscale precipitation. These HSLA are reported to have a good combination of strength, ductility and hole-expansion ability. In the current work, Gleeble ® 3500 torsion testing was employed to simulate the hot rolling process with varying run-out table cooling rates and coiling temperatures on five microalloyed steels with additions of Ti, Nb, Mo, Cr and V, to investigate the effects of microalloy additions and processing conditions on microstructures as well as mechanical properties. Subsized tensile specimens obtained from as-twisted torsion samples were used to evaluate mechanical properties. The precipitation states of the five steels with different processing conditions were characterized using extraction replica TEM. Comparison of microstructures and mechanical properties was discussed. Characterization of the microstructure via light optical microscopy showed the matrix microstructure was mainly influenced by coiling temperature, which indicates that the transformation from austenite to ferrite occurred during the coiling period. A higher Ti content was shown to reduce the second constituent fractions. Investigation of carbon extraction replica specimens via TEM revealed the presence of nanoscale precipitation. Extensive nanoscale precipitation was observed in most of the specimens having a polygonal ferrite matrix, while in the granular bainite/ferrite microstructure at lower temperatures, fewer microalloy carbides were present. The specimens with polygonal ferrite had similar or higher yield strength than the specimens with granular bainite microstructure, which suggests the effectiveness of precipitation strengthening from extensive nanoscale precipitates. In the Nb-Mo steel, more significant strengthening due to grain refinement was evident. Yield strength values were less than reported for JFE's "NANOHITEN

  7. Antireflective surface patterned by rolling mask lithography

    NASA Astrophysics Data System (ADS)

    Seitz, Oliver; Geddes, Joseph B.; Aryal, Mukti; Perez, Joseph; Wassei, Jonathan; McMackin, Ian; Kobrin, Boris

    2014-03-01

    A growing number of commercial products such as displays, solar panels, light emitting diodes (LEDs and OLEDs), automotive and architectural glass are driving demand for glass with high performance surfaces that offer anti-reflective, self-cleaning, and other advanced functions. State-of-the-art coatings do not meet the desired performance characteristics or cannot be applied over large areas in a cost-effective manner. "Rolling Mask Lithography" (RML™) enables highresolution lithographic nano-patterning over large-areas at low-cost and high-throughput. RML is a photolithographic process performed using ultraviolet (UV) illumination transmitted through a soft cylindrical mask as it rolls across a substrate. Subsequent transfer of photoresist patterns into the substrate is achieved using an etching process, which creates a nanostructured surface. The current generation exposure tool is capable of patterning one-meter long substrates with a width of 300 mm. High-throughput and low-cost are achieved using continuous exposure of the resist by the cylindrical photomask. Here, we report on significant improvements in the application of RML™ to fabricate anti-reflective surfaces. Briefly, an optical surface can be made antireflective by "texturing" it with a nano-scale pattern to reduce the discontinuity in the index of refraction between the air and the bulk optical material. An array of cones, similar to the structure of a moth's eye, performs this way. Substrates are patterned using RML™ and etched to produce an array of cones with an aspect ratio of 3:1, which decreases the reflectivity below 0.1%.

  8. Semi-Rolled Leaf2 modulates rice leaf rolling by regulating abaxial side cell differentiation

    PubMed Central

    Liu, Xiaofei; Li, Ming; Liu, Kai; Tang, Ding; Sun, Mingfa; Li, Yafei; Shen, Yi; Du, Guijie; Cheng, Zhukuan

    2016-01-01

    Moderate leaf rolling maintains the erectness of leaves and minimizes the shadowing between leaves which is helpful to establish ideal plant architecture. Here, we describe a srl2 (semi-rolled leaf2) rice mutant, which has incurved leaves due to the presence of defective sclerenchymatous cells on the abaxial side of the leaf and displays narrow leaves and reduced plant height. Map-based cloning revealed that SRL2 encodes a novel plant-specific protein of unknown biochemical function. SRL2 was mainly expressed in the vascular bundles of leaf blades, leaf sheaths, and roots, especially in their sclerenchymatous cells. The transcriptional activities of several leaf development-related YABBY genes were significantly altered in the srl2 mutant. Double mutant analysis suggested that SRL2 and SHALLOT-LIKE1 (SLL1)/ROLLED LEAF9 (RL9) function in distinct pathways that regulate abaxial-side leaf development. Hence, SRL2 plays an important role in regulating leaf development, particularly during sclerenchymatous cell differentiation. PMID:26873975

  9. Semi-Rolled Leaf2 modulates rice leaf rolling by regulating abaxial side cell differentiation.

    PubMed

    Liu, Xiaofei; Li, Ming; Liu, Kai; Tang, Ding; Sun, Mingfa; Li, Yafei; Shen, Yi; Du, Guijie; Cheng, Zhukuan

    2016-04-01

    Moderate leaf rolling maintains the erectness of leaves and minimizes the shadowing between leaves which is helpful to establish ideal plant architecture. Here, we describe asrl2(semi-rolled leaf2) rice mutant, which has incurved leaves due to the presence of defective sclerenchymatous cells on the abaxial side of the leaf and displays narrow leaves and reduced plant height. Map-based cloning revealed that SRL2 encodes a novel plant-specific protein of unknown biochemical function.SRL2 was mainly expressed in the vascular bundles of leaf blades, leaf sheaths, and roots, especially in their sclerenchymatous cells. The transcriptional activities of several leaf development-related YABBY genes were significantly altered in the srl2 mutant. Double mutant analysis suggested that SRL2 and SHALLOT-LIKE1(SLL1)/ROLLED LEAF9(RL9) function in distinct pathways that regulate abaxial-side leaf development. Hence, SRL2 plays an important role in regulating leaf development, particularly during sclerenchymatous cell differentiation.

  10. Rolling behavior of a micro-cylinder in adhesional contact

    NASA Astrophysics Data System (ADS)

    Saito, Shigeki; Ochiai, Toshihiro; Yoshizawa, Fumikazu; Dao, Ming

    2016-09-01

    Understanding the rolling behavior of a micro-object is essential to establish the techniques of micro-manipulation and micro-assembly by mechanical means. Using a combined theoretical/computational approach, we studied the critical conditions of rolling resistance of an elastic cylindrical micro-object in adhesional contact with a rigid surface. Closed-form dimensionless expressions for the critical rolling moment, the initial rolling contact area, and the initial rolling angle were extracted after a systematic parametric study using finite element method (FEM) simulations. The total energy of this system is defined as the sum of three terms: the elastic energy stored in the deformed micro-cylinder, the interfacial energy within the contact area, and the mechanical potential energy that depends on the external moment applied to the cylindrical micro-object. A careful examination of the energy balance of the system surprisingly revealed that the rolling resistance per unit cylindrical length can be simply expressed by “work of adhesion times cylindrical radius” independent of the Young’s modulus. In addition, extending a linear elastic fracture mechanics based approach in the literature, we obtained the exact closed-form asymptotic solutions for the critical conditions for initial rolling; these asymptotic solutions were found in excellent agreement with the full-field FEM results.

  11. Investigation of limb-sidestick dynamic interaction with roll control

    NASA Technical Reports Server (NTRS)

    Johnston, D. E.; Mcruer, D. T.

    1986-01-01

    A fixed-base simulation was performed to identify and quantify interactions between the pilot's hand/arm neuromuscular subsystem and such features of typical modern fighter aircraft roll rate command control system mechanization as: (1) force sensing side-stick type manipulator; (2) vehicle effective roll time constant; and (3) flight control system effective time delay. The simulation results provide insight to high frequency pilot induced oscillations (PIO) (roll ratchet), low frequency PIO, and roll-to-right control and handling problems previously observed in experimental and production fly-by-wire control systems. The simulation configurations encompass and/or duplicate several actual flight situations, reproduce control problems observed in flight, and validate the concept that the high frequency nuisance mode known as roll ratchet derives primarily from the pilot's neuromuscular subsystem. The simulations show that force-sensing side-stick manipulator force/displacement/command gradients, command prefilters, and flight control system time delays need to be carefully adjusted to minimize neuromuscular mode amplitude peaking (roll ratchet tendency) without restricting roll control bandwidth (with resulting sluggish or PIO prone control).

  12. Optimization of Resilient Wheels for Rolling Noise Control

    NASA Astrophysics Data System (ADS)

    BOUVET, PASCAL; VINCENT, NICOLAS; COBLENTZ, ARNAUD; DEMILLY, FRANÇOIS

    2000-03-01

    Resilient wheels are currently used on light rail systems such as tramways to prevent squealing noise and to reduce impact noise. On the other hand, they are rarely found on main lines (passenger rolling stock and freight rolling stock). Although manufacturers often claim that resilient wheels are favourable for rolling noise control, no extensive theoretical investigation confirming this statement has been published to date. In this paper, it is shown how resilient wheels can be effectively optimised in order to reduce rolling noise emission, compared to a conventional monobloc wheel. A preliminary analysis of the physical phenomena accounting for rolling noise generation emphasizes the key design parameters affecting both wheel and radiation. These parameters are the radial dynamic stiffness and damping loss factor of the rubber layer. The tread mass is also relevant. The influence of these design parameters is then qualified by a parametric study performed with the TWINS software. An optimum radial dynamic stiffness of the resilient layer is found which depends on operating conditions. Reductions in overall rolling noise up to 3 dB(A) are calculated for the configurations investigated. However, poor selection of the design parameters can lead to a noise increase compared to a standard monobloc wheel. It is also shown that a proper design for rolling noise control will not affect wheel efficiency with regard to squeal noise.

  13. Characteristics of electrohydrodynamic roll structures in laminar planar Couette flow

    NASA Astrophysics Data System (ADS)

    Kourmatzis, Agisilaos; Shrimpton, John S.

    2016-02-01

    The behaviour of an incompressible dielectric liquid subjected to a laminar planar Couette flow with unipolar charge injection is investigated numerically in two dimensions. The computations show new morphological characteristics of roll structures that arise in this forced electro-convection problem. The charge and velocity magnitude distributions between the two parallel electrodes are discussed as a function of the top wall velocity and the EHD Rayleigh number, T for the case of strong charge injection. A wide enough parametric space is investigated such that the observed EHD roll structures progress through three regimes. These regimes are defined by the presence of a single or double-roll free convective structure as observed elsewhere (Vazquez et al 2008 J. Phys. D 41 175303), a sheared or stretched roll structure, and finally by a regime where the perpendicular velocity gradient is sufficient to prevent the generation of a roll. These three regimes have been delineated as a function of the wall to ionic drift velocity {{U}\\text{W}}/κ E , and the T number. In the stretched regime, an increase in {{U}\\text{W}}/κ E can reduce charge and momentum fluctuations whilst in parallel de-stratify charge in the region between the two electrodes. The stretched roll regime is also characterised by a substantial influence of {{U}\\text{W}}/κ E on the steady development time, however in the traditional non-stretched roll structure regime, no influence of {{U}\\text{W}}/κ E on the development time is noted.

  14. Rolling behavior of a micro-cylinder in adhesional contact

    PubMed Central

    Saito, Shigeki; Ochiai, Toshihiro; Yoshizawa, Fumikazu; Dao, Ming

    2016-01-01

    Understanding the rolling behavior of a micro-object is essential to establish the techniques of micro-manipulation and micro-assembly by mechanical means. Using a combined theoretical/computational approach, we studied the critical conditions of rolling resistance of an elastic cylindrical micro-object in adhesional contact with a rigid surface. Closed-form dimensionless expressions for the critical rolling moment, the initial rolling contact area, and the initial rolling angle were extracted after a systematic parametric study using finite element method (FEM) simulations. The total energy of this system is defined as the sum of three terms: the elastic energy stored in the deformed micro-cylinder, the interfacial energy within the contact area, and the mechanical potential energy that depends on the external moment applied to the cylindrical micro-object. A careful examination of the energy balance of the system surprisingly revealed that the rolling resistance per unit cylindrical length can be simply expressed by “work of adhesion times cylindrical radius” independent of the Young’s modulus. In addition, extending a linear elastic fracture mechanics based approach in the literature, we obtained the exact closed-form asymptotic solutions for the critical conditions for initial rolling; these asymptotic solutions were found in excellent agreement with the full-field FEM results. PMID:27677706

  15. Engineering nanoscale surface features to sustain microparticle rolling in flow.

    PubMed

    Kalasin, Surachate; Santore, Maria M

    2015-05-26

    Nanoscopic features of channel walls are often engineered to facilitate microfluidic transport, for instance when surface charge enables electro-osmosis or when grooves drive mixing. The dynamic or rolling adhesion of flowing microparticles on a channel wall holds potential to accomplish particle sorting or to selectively transfer reactive species or signals between the wall and flowing particles. Inspired by cell rolling under the direction of adhesion molecules called selectins, we present an engineered platform in which the rolling of flowing microparticles is sustained through the incorporation of entirely synthetic, discrete, nanoscale, attractive features into the nonadhesive (electrostatically repulsive) surface of a flow channel. Focusing on one example or type of nanoscale feature and probing the impact of broad systematic variations in surface feature loading and processing parameters, this study demonstrates how relatively flat, weakly adhesive nanoscale features, positioned with average spacings on the order of tens of nanometers, can produce sustained microparticle rolling. We further demonstrate how the rolling velocity and travel distance depend on flow and surface design. We identify classes of related surfaces that fail to support rolling and present a state space that identifies combinations of surface and processing variables corresponding to transitions between rolling, free particle motion, and arrest. Finally we identify combinations of parameters (surface length scales, particle size, flow rates) where particles can be manipulated with size-selectivity.

  16. Modulation of high quality factors in rolled-up microcavities

    NASA Astrophysics Data System (ADS)

    Fang, Yangfu; Li, Shilong; Mei, Yongfeng

    2016-09-01

    We systematically investigate the evolution of resonant modes in a rolled-up microcavity as the overlap length between structural notches increases, which presents a modulation behavior for high Q factors. The resonant modes in the rolled-up microcavity display a deterministic mode chirality, which is well correlated to the Q factor. We derive a two-mode non-Hermitian Hamiltonian to clarify these unusual findings. It reveals that strong resonant interactions of scattered waves between the structural notches are responsible for the high mode chirality (thus high Q factor) and its modulation behavior in rolled-up microcavities.

  17. Access to the Commonwealth electoral roll for medical research.

    PubMed

    Loff, Bebe; Campbell, Elissa A; Glass, Deborah C; Kelsall, Helen L; Slegers, Claudia; Zion, Deborah R; Brown, Ngaire J; Fritschi, Lin

    2013-07-22

    In the 2010-11 financial 2013, there was a dramatic reduction in the approvals granted by the Australian Electoral Commission for access to samples of the adult population derived from the electoral roll for the purposes of public health research. Much time and effort has been expended in making applications without success. Researchers refused access to electoral roll samples must rely on sampling methods that are not as robust and that may produce less reliable data. We outline a set of recommendations that, if adopted, will result in a fairer system for obtaining access to the electoral roll for public health research.

  18. Development of closed loop roll control for magnetic balance systems

    NASA Technical Reports Server (NTRS)

    Covert, E. E.; Haldeman, C. W.; Ramohalli, G.; Way, P.

    1982-01-01

    This research was undertaken with the goal of demonstrating closed loop control of the roll degree of freedom on the NASA prototype magnetic suspension and balance system at the MIT Aerophysics Laboratory, thus, showing feasibility for a roll control system for any large magnetic balance system which might be built in the future. During the research under this grant, study was directed toward the several areas of torque generation, position sensing, model construction and control system design. These effects were then integrated to produce successful closed loop operation of the analogue roll control system. This experience indicated the desirability of microprocessor control for the angular degrees of freedom.

  19. Correcting Quadrupole Roll in Magnetic Lenses with Skew Quadrupoles

    SciTech Connect

    Walstrom, Peter Lowell

    2014-11-10

    Quadrupole rolls (i.e. rotation around the magnet axis) are known to be a significant source of image blurring in magnetic quadrupole lenses. These rolls may be caused by errors in mechanical mounting of quadrupoles, by uneven radiation-induced demagnetization of permanent-magnet quadrupoles, etc. Here a four-quadrupole ×10 lens with so-called ”Russian” or A -B B-A symmetry is used as a model problem. Existing SLAC 1/2 in. bore high-gradient quadrupoles are used in the design. The dominant quadrupole roll effect is changes in the first-order part of the transfer map (the R matrix) from the object to the image plane (Note effects on the R matrix can be of first order in rotation angle for some R-matrix elements and second order in rotation angle for other elements, as shown below). It is possible to correct roll-induced image blur by mechanically adjusting the roll angle of one or more of the quadrupoles. Usually, rotation of one quadrupole is sufficient to correct most of the combined effect of rolls in all four quadrupoles. There are drawbacks to this approach, however, since mechanical roll correction requires multiple entries into experimental area to make the adjustments, which are made according to their effect on images. An alternative is to use a single electromagnetic skew quadrupole corrector placed either between two of the quadrupoles or after the fourth quadrupole (so-called “non-local” correction). The basic feasibility of skew quadrupole correction of quadrupole roll effects is demonstrated here. Rolls of the third lens quadrupole of up to about 1 milliradian can be corrected with a 15 cm long skew quadrupole with a gradient of up to 1 T/m. Since the effect of rolls of the remaining three lens quadrupoles are lower, a weaker skew quadrupole can be used to correct them. Non-local correction of quadrupole roll effects by skew quadrupoles is shown to be about one-half as effective as local correction (i.e. rotating individual quadrupoles to zero

  20. Determination of residual stresses and natural frequencies of roll-tensioned disc by a dynamic simulation of the rolling process

    NASA Astrophysics Data System (ADS)

    Skordaris, G.; Bouzakis, K.-D.; Tasoulas, D.

    2017-02-01

    Roll tensioning is a common method for increasing locally the superficial strength of thin circular saws and in this way their dynamic stability. Through roll tensioning, residual stresses are induced into the disc material leading to a significant enhancement of its dynamic stiffness. In this paper, a FEM-methodology is proposed for determining the developed residual stresses in the discs after rolling and for investigating their effects on the circular saw natural frequencies. More specifically, a 3D-FEM model was developed for the dynamic simulation of the rolling process on circular saws, using the LS-DYNA software. This model enables the explicit determination of the developed residual stresses in the roll-tensioned discs. Furthermore, the natural frequencies of the pre-stressed circular saws were calculated by the ANSYS software. In these calculations, the already determined residual stresses were taken into consideration. Different distances of the roll-tensioned zone from the disc centre were taken into account for estimating their effect on the disc’s natural frequencies. By the proposed methodology, optimum roll-tensioning conditions can be predicted for improving the dynamic behaviour of thin circular saws during cutting.

  1. Effect of biomimetic coupling units' morphologies on rolling contact fatigue wear resistance of steel from machine tool rolling tracks

    NASA Astrophysics Data System (ADS)

    Yang, Wanshi; Zhou, Hong; Sun, Liang; Wang, Chuanwei; Chen, Zhikai

    2014-04-01

    The rolling contact fatigue wear resistance plays an important role on ensuring machining precision of machine tool using rolling tracks. Bio-inspired wearable surfaces with the alternated hardness were prepared on the specimen of steel material from machine tool rolling tracks by biomimetic coupling laser remelting method to imitate biological coupling principle. The microstructures and micromorphologies of bionic units in different sizes were characterized by optical microscope. The specimens with bionic units in different sizes and distributions were tested for rolling contact fatigue wear resistance. Combining the finite element analysis and the results of wear tests, a discussion on rolling contact fatigue wear was had. The specimens with bionic units had better rolling contact fatigue wear resistance than the untreated one, while the specimens with bionic units in the alternative depth's distributions present a better rolling contact fatigue wear resistance than the ones with bionic units in the single depth's distribution. It attributed to the alternative distribution made further improvement on the dispersion of depth of stress concentration.

  2. Rolling Process Modeling Report. Finite-Element Model Validation and Parametric Study on various Rolling Process parameters

    SciTech Connect

    Soulami, Ayoub; Lavender, Curt A.; Paxton, Dean M.; Burkes, Douglas

    2015-06-15

    Pacific Northwest National Laboratory (PNNL) has been investigating manufacturing processes for the uranium-10% molybdenum alloy plate-type fuel for high-performance research reactors in the United States. This work supports the U.S. Department of Energy National Nuclear Security Administration’s Office of Material Management and Minimization Reactor Conversion Program. This report documents modeling results of PNNL’s efforts to perform finite-element simulations to predict roll-separating forces for various rolling mill geometries for PNNL, Babcock & Wilcox Co., Y-12 National Security Complex, Los Alamos National Laboratory, and Idaho National Laboratory. The model developed and presented in a previous report has been subjected to further validation study using new sets of experimental data generated from a rolling mill at PNNL. Simulation results of both hot rolling and cold rolling of uranium-10% molybdenum coupons have been compared with experimental results. The model was used to predict roll-separating forces at different temperatures and reductions for five rolling mills within the National Nuclear Security Administration Fuel Fabrication Capability project. This report also presents initial results of a finite-element model microstructure-based approach to study the surface roughness at the interface between zirconium and uranium-10% molybdenum.

  3. Multilength Scale Patterning of Functional Layers by Roll-to-Roll Ultraviolet-Light-Assisted Nanoimprint Lithography.

    PubMed

    Leitgeb, Markus; Nees, Dieter; Ruttloff, Stephan; Palfinger, Ursula; Götz, Johannes; Liska, Robert; Belegratis, Maria R; Stadlober, Barbara

    2016-05-24

    Top-down fabrication of nanostructures with high throughput is still a challenge. We demonstrate the fast (>10 m/min) and continuous fabrication of multilength scale structures by roll-to-roll UV-nanoimprint lithography on a 250 mm wide web. The large-area nanopatterning is enabled by a multicomponent UV-curable resist system (JRcure) with viscous, mechanical, and surface properties that are tunable over a wide range to either allow for usage as polymer stamp material or as imprint resist. The adjustable elasticity and surface chemistry of the resist system enable multistep self-replication of structured resist layers. Decisive for defect-free UV-nanoimprinting in roll-to-roll is the minimization of the surface energies of stamp and resist, and the stepwise reduction of the stiffness from one layer to the next is essential for optimizing the reproduction fidelity especially for nanoscale features. Accordingly, we demonstrate the continuous replication of 3D nanostructures and the high-throughput fabrication of multilength scale resist structures resulting in flexible polyethylenetherephtalate film rolls with superhydrophobic properties. Moreover, a water-soluble UV-imprint resist (JRlift) is introduced that enables residue-free nanoimprinting in roll-to-roll. Thereby we could demonstrate high-throughput fabrication of metallic patterns with only 200 nm line width.

  4. 76 FR 15299 - Certain Hot-Rolled Carbon Steel Flat Products From India: Preliminary Rescission of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-21

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From India: Preliminary... countervailing duty (CVD) order on certain hot-rolled carbon steel flat products from India. See Antidumping or... The products covered under this order are certain hot-rolled flat- rolled carbon steel flat...

  5. 40 CFR 1066.225 - Roll runout and diameter verification procedure.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) Measure roll diameter using a Pi Tape®. Orient the Pi Tape® to the marker line at the desired measurement location with the Pi Tape® hook pointed outward. Temporarily secure the Pi Tape® to the roll near the hook end with adhesive tape. Slowly turn the roll, wrapping the Pi Tape® around the roll surface....

  6. Roll Forming of AHSS: Numerical Simulation and Investigation of Effects of Main Process Parameters on Quality

    NASA Astrophysics Data System (ADS)

    Salonitis, Konstantinos; Paralikas, John; Chryssolouris, George

    The roll forming process is one of the main processes of producing straight profiles in many industrial sectors. The introduction of Advanced High Strength Steels (AHSS), such as the DP and TRIP-series, into the production of roll-formed profiles has emerged new challenges. The combination of a higher yield strength with a lower total elongation of AHSS, brings new challenges to the roll forming process. In the current study, the numerical simulation of a V-section profile has been implemented. The effect of the main process parameters, such as the roll forming line velocity, rolls inter-distance, roll gap and rolls diameter on quality characteristics is investigated.

  7. Worm drive detail, roller hoist mechanism, rolling crest roller gate ...

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

    Worm drive detail, roller hoist mechanism, rolling crest roller gate - plan and sections - Grand Valley Diversion Dam, Half a mile north of intersection of I-70 & Colorado State Route 65, Cameo, Mesa County, CO

  8. Properties of doped boiler steel after controlled rolling

    SciTech Connect

    Bobylev, M.V.; Kireev, V.B.; Koreshkova, A.M.

    1992-03-01

    The article shows that the structural strength of carbon boiler steel type 20K can be enhanced by doping with vanadium or niobium and by controlled rolling and controlled cooling. 8 refs., 6 figs., 1 tab.

  9. 9. DETAIL VIEW OF ROLLING EXPANSION JOINT, NORTHEAST BASE OF ...

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

    9. DETAIL VIEW OF ROLLING EXPANSION JOINT, NORTHEAST BASE OF SECOND CLOSED SPANDREL ARCH AT JUNCTION OF OPEN SPANDREL ARCH, LOOKING EAST - Virgin River Bridge, Spanning Virgin River on State Highway 9, Hurricane, Washington County, UT

  10. Facility No. 175, interior detail showing rolling doors, trusses, and ...

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

    Facility No. 175, interior detail showing rolling doors, trusses, and angled monitor roof - U.S. Naval Base, Pearl Harbor, Landplane Hangar Type, Wasp Boulevard and Gambier Bay Street, Pearl City, Honolulu County, HI

  11. The Variation of Yawing Moment Due to Rolling

    NASA Technical Reports Server (NTRS)

    Wilson, Edwin Bidwell

    1918-01-01

    The aerodynamical constants of an airplane necessary for the discussion of stability are partly observed and partly calculated. Among the calculated coefficients is n(p), which is the variation of yawing moment due to rolling. (author)

  12. Adaptive methods, rolling contact, and nonclassical friction laws

    NASA Technical Reports Server (NTRS)

    Oden, J. T.

    1989-01-01

    Results and methods on three different areas of contemporary research are outlined. These include adaptive methods, the rolling contact problem for finite deformation of a hyperelastic or viscoelastic cylinder, and non-classical friction laws for modeling dynamic friction phenomena.

  13. SMALL DIAMETER STENCILING, ROLLING OVER STAMP. United States Pipe ...

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

    SMALL DIAMETER STENCILING, ROLLING OVER STAMP. - United States Pipe & Foundry Company Plant, Coating, Painting, Lining & Packaging Building, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  14. Hydrodynamic properties of fin whale flippers predict maximum rolling performance.

    PubMed

    Segre, Paolo S; Cade, David E; Fish, Frank E; Potvin, Jean; Allen, Ann N; Calambokidis, John; Friedlaender, Ari S; Goldbogen, Jeremy A

    2016-11-01

    Maneuverability is one of the most important and least understood aspects of animal locomotion. The hydrofoil-like flippers of cetaceans are thought to function as control surfaces that effect maneuvers, but quantitative tests of this hypothesis have been lacking. Here, we constructed a simple hydrodynamic model to predict the longitudinal-axis roll performance of fin whales, and we tested its predictions against kinematic data recorded by on-board movement sensors from 27 free-swimming fin whales. We found that for a given swimming speed and roll excursion, the roll velocity of fin whales calculated from our field data agrees well with that predicted by our hydrodynamic model. Although fluke and body torsion may further influence performance, our results indicate that lift generated by the flippers is sufficient to drive most of the longitudinal-axis rolls used by fin whales for feeding and maneuvering.

  15. 18. DETAIL OF ROLLING DOORS AND CANOPY AT SOUTH SIDE ...

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

    18. DETAIL OF ROLLING DOORS AND CANOPY AT SOUTH SIDE ENTRANCE, ALSO SEEN FROM A DISTANCE IN VIEW NO. CA-295-A-15. - United Engineering Company Shipyard, Inspection & Repair Shops, 2900 Main Street, Alameda, Alameda County, CA

  16. 2. BARN. VIEW LOOKING NORTHWEST. THE ROLLING DOOR PROBABLY REPLACES ...

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

    2. BARN. VIEW LOOKING NORTHWEST. THE ROLLING DOOR PROBABLY REPLACES AN ORIGINAL 4/4 DOUBLE-HUNG WINDOW. - Tonto Ranger Station, Barn, Forest Service Road 65 at Tonto Wash, Skull Valley, Yavapai County, AZ

  17. Dynamic Effect of Rolling Massage on Blood Flow

    NASA Astrophysics Data System (ADS)

    Chen, Yan-Yan; Yi, Hou-Hui; Li, Hua-Bing; Fang, Hai-Ping

    2009-02-01

    The Chinese traditional medical massage has been used as a natural therapy to eliminate some diseases. Here, the effect of the rolling massage frequency to the blood flow in the blood vessels under the rolling massage manipulation is studied by the lattice Boltzmann simulation. The simulation results show that when the frequency is smaller than or comparable to the pulsatile frequency of the blood flow, the effect on the blood flux by the rolling massage is small. On the contrast, if the frequency is twice or more times of the pulsatile frequency of the blood flow, the blood flux is greatly enhanced and increases linearly with respect to the frequency. Similar behavior has also been observed on the shear stress on the blood vessel walls. The result is helpful for understanding that the rolling massage has the function of promoting the blood circulation and removing the blood stasis.

  18. 11. DETAIL SHOWING ROLLING ENGINE DECK AND NORTHEAST TRUSS OF ...

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

    11. DETAIL SHOWING ROLLING ENGINE DECK AND NORTHEAST TRUSS OF SUPERSTRUCTURE. Looking northeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  19. MAIN DRIVE MOTOR FOR BLISS #43 HOT ROLL. THIS WESTINGHOUSE ...

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

    MAIN DRIVE MOTOR FOR BLISS #43 HOT ROLL. THIS WESTINGHOUSE UNIT HAS SINCE BEEN REPLACED BY A 5000 HP TOSHIBA MOTOR. REHEAT FURNACES ARE SHOWN BEHIND MILL MOTOR. - American Brass Foundry, 70 Sayre Street, Buffalo, Erie County, NY

  20. Orbital Rolls to Launch Pad at Wallops for Station Flight

    NASA Video Gallery

    An Orbital Sciences Corporation Antares rolled out to launch Pad-0A at NASA's Wallops Flight Facility, Sunday, January 5, 2014, in advance of a planned Wednesday, Jan. 8th, 1:32 p.m. EST launch. Th...

  1. Floor Plans Rolling Platform, Tech Systems Platform, and Load ...

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

    Floor Plans - Rolling Platform, Tech Systems Platform, and Load Platform Plans - Marshall Space Flight Center, F-1 Engine Static Test Stand, On Route 565 between Huntsville and Decatur, Huntsville, Madison County, AL

  2. Correlating microstructure and texture in cold-rolled Ta ingot

    SciTech Connect

    Feng, C. ); Kumar, P. )

    1989-10-01

    An analysis of tantalum ingot cold-rolled and annealed under different conditions reveals several correlations between the microstructure, developed textures and thermomechanical processing parameters. For example, the hardness of rolled sheet is not significantly affected by the amount of reduction prior to the final anneal, while the final grain size decreases with an increasing number of intermediate annealing steps. Four classes of texture are found in the cold-rolled tantalum, but the finger-grained classes can only be produced via a 70 percent reduction in thickness prior to the final anneal. Although ample dislocation debris is produced by the rolling operation, clearly defined line dislocations and dislocations networks are absent, indicating that full recrystallization is not achieved in the finished sheets. A large concentration of ledge dislocations at the grain boundary regions is considered an important contributor to the good formability of tantalum.

  3. Rolling bearing fault diagnosis using an optimization deep belief network

    NASA Astrophysics Data System (ADS)

    Shao, Haidong; Jiang, Hongkai; Zhang, Xun; Niu, Maogui

    2015-11-01

    The vibration signals measured from a rolling bearing are usually affected by the variable operating conditions and background noise which lead to the diversity and complexity of the vibration signal characteristics, and it is a challenge to effectively identify the rolling bearing faults from such vibration signals with no further fault information. In this paper, a novel optimization deep belief network (DBN) is proposed for rolling bearing fault diagnosis. Stochastic gradient descent is used to efficiently fine-tune all the connection weights after the pre-training of restricted Boltzmann machines (RBMs) based on the energy functions, and the classification accuracy of the DBN is improved. Particle swarm is further used to decide the optimal structure of the trained DBN, and the optimization DBN is designed. The proposed method is applied to analyze the simulation signal and experimental signal of a rolling bearing. The results confirm that the proposed method is more accurate and robust than other intelligent methods.

  4. Formation of the Goss orientation near the surface of 3 pct silicon steel during hot rolling

    NASA Astrophysics Data System (ADS)

    Shimizu, Y.; Ito, Y.; Iida, Y.

    1986-08-01

    The influence of hot rolling conditions such as reduction rate, rolling temperature, rolling speed, lubrication, and initial orientation on the formation of the Goss orientation near the surface of hot rolled 3 Pct silicon steel was studied. A (110) [001] orientation was stably formed at the reduction rate of over 85 Pct in any initial orientation used, even from (100) [001] and (100) [011] single crystals. A strong (110) [001] orientation was obtained in the specimen hot rolled by multi-pass rolling (low reduction rate per pass) and by slower speed rolling in the range of 6 to 50 m/min. It was found that the Goss orientation was formed not by recrystallization during and after hot rolling but by slip rotation near the surface due to constrained deformation. The high friction between the roll and sheet characteristic to hot rolling was important for this texture formation.

  5. Computer-aided analysis and design of the shape rolling process for producing turbine engine airfoils

    NASA Technical Reports Server (NTRS)

    Lahoti, G. D.; Akgerman, N.; Altan, T.

    1978-01-01

    Mild steel (AISI 1018) was selected as model cold rolling material and Ti-6A1-4V and Inconel 718 were selected as typical hot rolling and cold rolling alloys, respectively. The flow stress and workability of these alloys were characterized and friction factor at the roll/workpiece interface was determined at their respective working conditions by conducting ring tests. Computer-aided mathematical models for predicting metal flow and stresses, and for simulating the shape rolling process were developed. These models utilized the upper bound and the slab methods of analysis, and were capable of predicting the lateral spread, roll separating force, roll torque, and local stresses, strains and strain rates. This computer-aided design system was also capable of simulating the actual rolling process, and thereby designing the roll pass schedule in rolling of an airfoil or a similar shape.

  6. Effects of microalloying on hot-rolled and cold-rolled Q&P steels

    NASA Astrophysics Data System (ADS)

    Azevedo de Araujo, Ana Luiza

    Third generation advanced high strength steels (AHSS) have been a major focus in steel development over the last decade. The premise of these types of steel is based on the potential to obtain excellent combinations of strength and ductility with low-alloy compositions by forming mixed microstructures containing retained austenite (RA). The development of heat treatments able to achieve the desired structures and properties, such as quenching and partitioning (Q&P) steels, is driven by new requirements to increase vehicle fuel economy by reducing overall weight while maintaining safety and crashworthiness. Microalloying additions of niobium (Nb) and vanadium (V) in sheet products are known to provide strengthening via grain refinement and precipitation hardening and may influence RA volume fraction and transformation behavior. Additions of microalloying elements in Q&P steels have not been extensively studied to date, however. The objective of the present study was to begin to understand the potential roles of Nb and V in hot-rolled and cold-rolled Q&P steel. For that, a common Q&P steel composition was selected as a Base alloy with 0.2C-1.5Si-2.0Mn (wt. %). Two alloys with an addition of Nb (0.02 and 0.04 wt. %) and one with an addition of V (0.06 wt. %) to the Base alloy were investigated. Both hot-rolled and cold-rolled/annealed Q&P simulations were conducted. In the hot-rolled Q&P study, thermomechanical processing was simulated via hot torsion testing in a GleebleRTM 3500, and four coiling temperatures (CT) were chosen. Microstructural evaluation (including RA measurements via electron backscattered diffraction - EBSD) and hardness measurements were performed for all alloys and coiling conditions. The analysis showed that Nb additions led to overall refinement of the prior microstructure. Maximum RA fractions were measured at the 375 °C CT, and microalloying was associated with increased RA in this condition when compared to the Base alloy. A change in

  7. Roll Aftereffects: Influence of tilt and inter-stimulus interval

    PubMed Central

    Crane, Benjamin T.

    2012-01-01

    A theme in sensory perception it that exposure to a stimulus causes perception of subsequent stimuli to be shifted in the opposite direction. Such phenomenon are known as aftereffects and have been extensively described in the visual system as well as recently described for the vestibular system during translation. It is known from aviation studies that after a maneuver in roll pilots can experience a false perception of roll in the opposite direction. The magnitude and duration of this effect as well as the potential influence of the gravity vector have not previously been defined. In the current paper this roll aftereffect (RAE) is examined in response to whole body roll about an earth-horizontal axis in eight healthy human subjects. The peak velocity of a 0.5 s duration roll was varied based on previous responses to find the point where subjects perceived no motion. Without an preceding stimulus the starting position (upright, 9° left, or 9° right) did not influence roll perception. The RAE was measured in a completely dark room using an adapting (firstinterval) stimulus consisting of 9° of roll over 1.5 s (peak velocity 12°/s), delivered 0.5, 3, or 6s prior to test (second-interval) stimulus. A significant RAE was seen in all subjects. Half a second after the adapting stimulus a test stimulus had to be on average 1.5 ± 0.4°/s in the opposite direction to be perceived as stationary. When the subject remained upright after the adapting stimulus the RAE diminished with time, although it remained significantly larger at 3s and 6s when the subject remained tilted after the adapting stimulus. These data demonstrate that roll perception can be influenced by small preceding stimuli and tilt causes a persistence of the RAE. PMID:22945611

  8. Wheel rolling constraints and slip in mobile robots

    SciTech Connect

    Shekhar, S.

    1996-06-01

    It is widely accepted that dead-reckoning based on the rolling with no-slip condition on the wheels is not a reliable method to ascertain the position and orientation of a mobile robot for any reasonable distance. The authors establish that wheel slip is inevitable under the dynamic model of motion using classical results on the accessibility and controllability in nonlinear control theory and an analytical model of rolling of two linearly elastic bodies.

  9. Wheel rolling constraints and slip in mobile robots

    SciTech Connect

    Shekhar, S.

    1997-03-01

    It is widely accepted that dead reckoning based on the rolling with no slip condition on wheels is not a reliable method to ascertain the position and orientation of a mobile robot for any reasonable distance. The author establishes that wheel slip is inevitable under the dynamic model of motion using classical results on the accessibility and controllability in nonlinear control theory and an analytical model of rolling of two linearly elastic bodies.

  10. Wheel rolling constraints and slip in mobile robots

    SciTech Connect

    Shekhar, S.

    1997-03-01

    It is widely accepted that dead reckoning based on the rolling with no slip condition on wheels is not a reliable method to ascertain the position and orientation of a mobile robot for any reasonable distance. We establish that wheel slip is inevitable under the dynamic model of motion using classical results on the accessibility and controllability in nonlinear control theory and an analytical model of rolling of two linearly elastic bodies.

  11. Mesomorphic Lamella Rolling of Au in Vacuum

    NASA Astrophysics Data System (ADS)

    Huang, Chang-Ning; Chen, Shuei-Yuan; Shen, Pouyan

    2009-07-01

    Lamellar nanocondensates in partial epitaxy with larger-sized multiply twinned particles (MTPs) or alternatively in the form of multiple-walled tubes (MWTs) having nothing to do with MTP were produced by the very energetic pulse laser ablation of Au target in vacuum under specified power density and pulses. Transmission electron microscopic observations revealed (111)-motif diffraction and low-angle scattering. They correspond to layer interspacing (0.241-0.192 nm) and the nearest neighbor distance (ca. 0.74-0.55 nm) of atom clusters within the layer, respectively, for the lamella, which shows interspacing contraction with decreasing particle size under the influence of surface stress and rolls up upon electron irradiation. The uncapped MWT has nearly concentric amorphous layers interspaced by 0.458-0.335 nm depending on dislocation distribution and becomes spherical onions for surface-area reduction upon electron dosage. Analogous to graphene-derived tubular materials, the lamella-derived MWT of Au could have pentagon-hexagon pair at its zig-zag junction and useful optoelectronic properties worthy of exploration.

  12. An improved rolled strip pulse forming line.

    PubMed

    Li, Song; Qian, Bao-Liang; Yang, Han-Wu; Gao, Jing-Ming; Liu, Zhao-Xi

    2013-06-01

    The rolled strip pulse forming line (RSPFL) has advantages of compactness, portability, and long pulse achievability which could well meet the requirements of industrial application of the pulse power technology. In this paper, an improved RSPFL with an additional insulator between the grounded conductors is investigated numerically and experimentally. Results demonstrate that the jitter on the flat-top of the output voltage waveform is reduced to 3.8% due to the improved structure. Theoretical analysis shows that the electromagnetic coupling between the conductors of the RSPFL strongly influences the output voltage waveform. Therefore, the new structure was designed to minimize the detrimental effect of the electromagnetic coupling. Simulation results show that the electromagnetic coupling can be efficiently reduced in the improved RSPFL. Experimental results illustrate that the improved RSPFL, with dimensions and weight of Φ 290 × 250 mm and 16 kg, when used as a simple pulse forming line, could generate a well shaped quasi-square pulse with output power of hundreds of MW and pulse duration of 250 ns. Importantly, the improved RSPFL was successfully used as a Blumlein pulse forming line, and a 10.8 kV, 260 ns quasi-square pulse was obtained on a 2 Ω dummy load. Experiments show reasonable agreement with numerical analysis.

  13. Mesomorphic Lamella Rolling of Au in Vacuum

    PubMed Central

    2009-01-01

    Lamellar nanocondensates in partial epitaxy with larger-sized multiply twinned particles (MTPs) or alternatively in the form of multiple-walled tubes (MWTs) having nothing to do with MTP were produced by the very energetic pulse laser ablation of Au target in vacuum under specified power density and pulses. Transmission electron microscopic observations revealed (111)-motif diffraction and low-angle scattering. They correspond to layer interspacing (0.241–0.192 nm) and the nearest neighbor distance (ca. 0.74–0.55 nm) of atom clusters within the layer, respectively, for the lamella, which shows interspacing contraction with decreasing particle size under the influence of surface stress and rolls up upon electron irradiation. The uncapped MWT has nearly concentric amorphous layers interspaced by 0.458–0.335 nm depending on dislocation distribution and becomes spherical onions for surface-area reduction upon electron dosage. Analogous to graphene-derived tubular materials, the lamella-derived MWT of Au could have pentagon–hexagon pair at its zig-zag junction and useful optoelectronic properties worthy of exploration. PMID:20628452

  14. Communication using eye roll reflective signalling

    USGS Publications Warehouse

    Flamarique, I.N.; Mueller, G.A.; Cheng, C.L.; Figiel, C.R.

    2007-01-01

    Body reflections in the ultraviolet (UV) are a common occurrence in nature. Despite the abundance of such signals and the presence of UV cones in the retinas of many vertebrates, the function of UV cones in the majority of taxa remains unclear. Here, we report on an unusual communication system in the razorback sucker, Xyrauchen texanus, that involves flash signals produced by quick eye rolls. Behavioural experiments and field observations indicate that this form of communication is used to signal territorial presence between males. The flash signal shows highest contrast in the UV region of fhe visual spectrum (??max???380 nm), corresponding to the maximum wavelength of absorption of the UV cone mechanism in suckers. Furthermore, these cones are restricted to the dorsal retina of the animal and the upwelling light background is such that their relative sensitivity would be enhanced by chromatic adaptation of the other cone mechanisms. Thus, the UV cones in the sucker have optimal characteristics (both in terms of absorbance and retinal topography) to constitute the main detectors of the flash signal. Our findings provide the first ecological evidence for restricted distribution of UV cones in the retina of a vertebrate. ?? 2007 The Royal Society.

  15. Rolling-circle replication of bacterial plasmids.

    PubMed Central

    Khan, S A

    1997-01-01

    Many bacterial plasmids replicate by a rolling-circle (RC) mechanism. Their replication properties have many similarities to as well as significant differences from those of single-stranded DNA (ssDNA) coliphages, which also replicate by an RC mechanism. Studies on a large number of RC plasmids have revealed that they fall into several families based on homology in their initiator proteins and leading-strand origins. The leading-strand origins contain distinct sequences that are required for binding and nicking by the Rep proteins. Leading-strand origins also contain domains that are required for the initiation and termination of replication. RC plasmids generate ssDNA intermediates during replication, since their lagging-strand synthesis does not usually initiate until the leading strand has been almost fully synthesized. The leading- and lagging-strand origins are distinct, and the displaced leading-strand DNA is converted to the double-stranded form by using solely the host proteins. The Rep proteins encoded by RC plasmids contain specific domains that are involved in their origin binding and nicking activities. The replication and copy number of RC plasmids, in general, are regulated at the level of synthesis of their Rep proteins, which are usually rate limiting for replication. Some RC Rep proteins are known to be inactivated after supporting one round of replication. A number of in vitro replication systems have been developed for RC plasmids and have provided insight into the mechanism of plasmid RC replication. PMID:9409148

  16. An improved rolled strip pulse forming line

    NASA Astrophysics Data System (ADS)

    Li, Song; Qian, Bao-Liang; Yang, Han-Wu; Gao, Jing-Ming; Liu, Zhao-Xi

    2013-06-01

    The rolled strip pulse forming line (RSPFL) has advantages of compactness, portability, and long pulse achievability which could well meet the requirements of industrial application of the pulse power technology. In this paper, an improved RSPFL with an additional insulator between the grounded conductors is investigated numerically and experimentally. Results demonstrate that the jitter on the flat-top of the output voltage waveform is reduced to 3.8% due to the improved structure. Theoretical analysis shows that the electromagnetic coupling between the conductors of the RSPFL strongly influences the output voltage waveform. Therefore, the new structure was designed to minimize the detrimental effect of the electromagnetic coupling. Simulation results show that the electromagnetic coupling can be efficiently reduced in the improved RSPFL. Experimental results illustrate that the improved RSPFL, with dimensions and weight of Φ 290 × 250 mm and 16 kg, when used as a simple pulse forming line, could generate a well shaped quasi-square pulse with output power of hundreds of MW and pulse duration of 250 ns. Importantly, the improved RSPFL was successfully used as a Blumlein pulse forming line, and a 10.8 kV, 260 ns quasi-square pulse was obtained on a 2 Ω dummy load. Experiments show reasonable agreement with numerical analysis.

  17. Stochastic Prognostics for Rolling Element Bearings

    NASA Astrophysics Data System (ADS)

    Li, Y.; Kurfess, T. R.; Liang, S. Y.

    2000-09-01

    The capability to accurately predict the remaining life of a rolling element bearing is prerequisite to the optimal maintenance of rotating machinery performance in terms of cost and productivity. Due to the probabilistic nature of bearing integrity and operation condition, reliable estimation of a bearing's remaining life presents a challenging aspect in the area of maintenance optimisation and catastrophic failure avoidance. Previous study has developed an adaptive prognostic methodology to estimate the rate of bearing defect growth based on a deterministic defect-propagation model. However, deterministic models are inadequate in addressing the stochastic nature of defect-propagation. In this paper, a stochastic defect-propagation model is established by instituting a lognormal random variable in a deterministic defect-propagation rate model. The resulting stochastic model is calibrated on-line by a recursive least-squares (RLS) approach without the requirement of a priori knowledge on bearing characteristics. An augmented stochastic differential equation vector is developed with the consideration of model uncertainties, parameter estimation errors, and diagnostic model inaccuracies. It involves two ordinary differential equations for the first and second moments of its random variables. Solving the two equations gives the mean path of defect propagation and its dispersion at any instance. This approach is suitable for on-line monitoring, remaining life prediction, and decision making for optimal maintenance scheduling. The methodology has been verified by numerical simulations and the experimental testing of bearing fatigue life.

  18. Communication using eye roll reflective signalling.

    PubMed

    Novales Flamarique, I; Mueller, G A; Cheng, C L; Figiel, C R

    2007-03-22

    Body reflections in the ultraviolet (UV) are a common occurrence in nature. Despite the abundance of such signals and the presence of UV cones in the retinas of many vertebrates, the function of UV cones in the majority of taxa remains unclear. Here, we report on an unusual communication system in the razorback sucker, Xyrauchen texanus, that involves flash signals produced by quick eye rolls. Behavioural experiments and field observations indicate that this form of communication is used to signal territorial presence between males. The flash signal shows highest contrast in the UV region of the visual spectrum (lambdamax approximately 380 nm), corresponding to the maximum wavelength of absorption of the UV cone mechanism in suckers. Furthermore, these cones are restricted to the dorsal retina of the animal and the upwelling light background is such that their relative sensitivity would be enhanced by chromatic adaptation of the other cone mechanisms. Thus, the UV cones in the sucker have optimal characteristics (both in terms of absorbance and retinal topography) to constitute the main detectors of the flash signal. Our findings provide the first ecological evidence for restricted distribution of UV cones in the retina of a vertebrate.

  19. Bioinspired superhydrophobic surfaces, fabricated through simple and scalable roll-to-roll processing

    NASA Astrophysics Data System (ADS)

    Park, Sung-Hoon; Lee, Sangeui; Moreira, David; Bandaru, Prabhakar R.; Han, Intaek; Yun, Dong-Jin

    2015-10-01

    A simple, scalable, non-lithographic, technique for fabricating durable superhydrophobic (SH) surfaces, based on the fingering instabilities associated with non-Newtonian flow and shear tearing, has been developed. The high viscosity of the nanotube/elastomer paste has been exploited for the fabrication. The fabricated SH surfaces had the appearance of bristled shark skin and were robust with respect to mechanical forces. While flow instability is regarded as adverse to roll-coating processes for fabricating uniform films, we especially use the effect to create the SH surface. Along with their durability and self-cleaning capabilities, we have demonstrated drag reduction effects of the fabricated films through dynamic flow measurements.

  20. Observations and Modelling of Convective Rolls Over Low Hills

    NASA Astrophysics Data System (ADS)

    Tian, W.; Parker, D. J.; Kilburn, C. A. D.

    Radar and satellite images provide observations of convective rolls and other struc- tures in the convective boundary layer (CBL), but numerical modelling is a neces- sary complement to the observations, to investigate the temporal and spatial evolu- tion of convective rolls. Numerical simulations have been performed to investigate observed convective rolls over the south of England, using BLASIUS, a relatively simple boundary layer code for flow over topography. The principal features of the convective structures can be successfully reproduced by the model, notably the roll orientation and spacing and the basic features of the cloud field. These features are in good agreement for two case studies, one with distinct rolls and the other with more dispersed convective structures and a time-dependent basic state. The presence of low topography (with maximum height of order 30% of the CBL depth) does not significantly change the orientation and spacing, nor the time of initial occurrence of modelled rolls, but local flow anomalies can be related to the hills. These anomalies are related to coherent patterns in the diagnosed cloud fields, with a tendency for more cloud cover upstream and over hills, and cloud clearing in the lee as a result of descent suppressing convective eddies. This kind of control of the shallow convection by the topography is evident in the satellite imagery.

  1. Multiparticle adhesive dynamics. Interactions between stably rolling cells.

    PubMed Central

    King, M R; Hammer, D A

    2001-01-01

    A novel numerical simulation of adhesive particles (cells) reversibly interacting with an adhesive surface under flow is presented. Particle--particle and particle--wall hydrodynamic interactions in low Reynolds number Couette flow are calculated using a boundary element method that solves an integral representation of the Stokes equation. Molecular bonds between surfaces are modeled as linear springs and stochastically formed and broken according to postulated descriptions of force-dependent kinetics. The resulting simulation, Multiparticle Adhesive Dynamics, is applied to the problem of selectin-mediated rolling of hard spheres coated with leukocyte adhesion molecules (cell-free system). Simulation results are compared to flow chamber experiments performed with carbohydrate-coated spherical beads rolling on P-selectin. Good agreement is found between theory and experiment, with the main observation being a decrease in rolling velocity with increasing concentration of rolling cells or increasing proximity between rolling cells. Pause times are found to increase and deviation motion is found to decrease as pairs of rolling cells become closer together or align with the flow. PMID:11463626

  2. Twisting, Rolling Motions, and Helicity in Prominence Eruptions

    NASA Astrophysics Data System (ADS)

    McKillop, Sean; Miralles, Mari Paz; Murphy, Nicholas A.; McCauley, Patrick; Su, Yingna

    2015-04-01

    Panasenco et al. [1] report observations of several CMEs that display a rolling motion about the axis of the erupting prominence. Murphy et al. [2] present simulations of line-tied asymmetric magnetic reconnection that make a falsifiable prediction regarding the handedness of rolling motions of flux ropes during solar eruptions. Mass motions in prominence eruptions tend to be complicated and characterizing these motions is a challenge. We use the AIA filament eruption catalog [3] as a source for finding events. If rolling motions are detected then we will investigate the handedness prediction. We use magnetograms from HMI to determine the strength and asymmetric properties of the photospheric magnetic field in the regions of interest and will use AIA observations to determine the handedness of the rolling motions. We then compare the photospheric magnetic information with the handedness to determine if there is a relationship between the two. We also determine the chirality of the prominences to see if there is any interesting relationship to the twist, rolling motion and/or handedness of the roll.[1] O. Panasenco, S. Martin, A. D. Joshi, & N. Srivastava, J. Atmos. Sol.-Terr. Phys., 73, 1129 (2011)[2] N. A. Murphy, M. P. Miralles, C. L. Pope, J. C. Raymond, H. D. Winter, K. K. Reeves, D. B. Seaton, A. A. van Ballegooijen, & J. Lin, ApJ, 751, 56 (2012)[3] http://aia.cfa.harvard.edu/filament/

  3. Rolling-Element Fatigue Testing and Data Analysis - A Tutorial

    NASA Technical Reports Server (NTRS)

    Vlcek, Brian L.; Zaretsky, Erwin V.

    2011-01-01

    In order to rank bearing materials, lubricants and other design variables using rolling-element bench type fatigue testing of bearing components and full-scale rolling-element bearing tests, the investigator needs to be cognizant of the variables that affect rolling-element fatigue life and be able to maintain and control them within an acceptable experimental tolerance. Once these variables are controlled, the number of tests and the test conditions must be specified to assure reasonable statistical certainty of the final results. There is a reasonable correlation between the results from elemental test rigs with those results obtained with full-scale bearings. Using the statistical methods of W. Weibull and L. Johnson, the minimum number of tests required can be determined. This paper brings together and discusses the technical aspects of rolling-element fatigue testing and data analysis as well as making recommendations to assure quality and reliable testing of rolling-element specimens and full-scale rolling-element bearings.

  4. Computation of Viscous Free-Surface Hydrodynamics for Ships during Free-Roll, Wave-Excited Roll and Prescribed Motions

    NASA Astrophysics Data System (ADS)

    Smith, Kevin; Paterson, Eric

    2008-11-01

    Prediction of ship motions in waves and the role of viscous effects remains an important problem in naval hydrodynamics. A computational fluid dynamics (CFD) solver has been developed which can simulate the unsteady turbulent boundary layer, wave field, and 6DOF dynamics of a floating body in waves. The solver is based upon the Reynolds-averaged Navier-Stokes equations, and volume-of-fluid (VOF) and dynamic-meshing algorithms. It is used to study free-roll, wave-excited roll, and forced heave and sway motions. Solution validation is achieved by comparing roll-amplitude decay, natural frequency, and response amplitude operator (RAO) for a 2D box barge in regular waves to experimental data. As a practical example, a ship hullform, with and without bilge keels, is studied when undergoing prescribed roll, sway, and heave motions. Details of the fluid dynamics and forces and moments will be correlated to motion amplitudes and frequencies.

  5. Powder lubrication of faults by powder rolls in gouge zones

    NASA Astrophysics Data System (ADS)

    Chen, X.; Madden, A. S.; Reches, Z.

    2013-12-01

    Powder-lubrication by fault gouge can be an effective mechanism of dynamic weakening of faults (Reches & Lockner, 2010); however, the physical mechanisms of this lubrication are poorly understood. While the flow of coarse-grained (> 100 μm) materials, e.g. glass beads or quartz sand, was extensively studied, the flow of fine-grained (< 1 μm) powders, e.g., fault-gouge and nano-powders, have remained enigmatic. We report here experimental results of a new efficient mechanism for powder lubrication. We conducted friction tests on high-velocity rotary shear apparatus (Reches & Lockner, 2010). Two types of experimental faults were tested: (1) faults made of solid, igneous rocks (granite, tonalite and diorite); and (2) fault-zones made of 2-3 mm thick layer of granular materials (oolites, calcite or gypsum) sheared in a confined cell. We performed 21 runs with total slip of 0.14-13 m, normal stress of 1.2-14.5 MPa, slip velocity of 0.012-0.97 m/s. The ultra-microscopic (SEM and AFM) analysis of the experimental slip surfaces revealed two outstanding features in 17 out of the 21 experiments: (1) localized fault-slip along Principal Slip Zones (PSZs) that are composed of a dense, shiny, cohesive crust, 0.5-1 micron thick, that overlaid a porous substrate, and (2) elongated rolls composed of gouge-powder into three-dimensional structures of closely-packed powder grains, (20-50 nm in size). The rolls are cylindrical, 0.75-1.4 micron wide, and 1.7-30 micron long, with smooth outer surface, and laminated, concentric layers of compacted grains. The rolls were exclusively found on the PSZs. Many rolls were destroyed fracturing and smearing on the PSZ, suggesting that the rolls underwent a life cycle of formation and destruction. Significant macroscopic friction reduction was measured in experiments with observed rolls, and no (or minor) friction reduction in the four experiments without rolls. The final, reduced friction coefficients have a general reciprocal relation to the

  6. Roll-to-Roll Green Transfer of CVD Graphene onto Plastic for a Transparent and Flexible Triboelectric Nanogenerator.

    PubMed

    Chandrashekar, Bananakere Nanjegowda; Deng, Bing; Smitha, Ankanahalli Shankaregowda; Chen, Yubin; Tan, Congwei; Zhang, Haixia; Peng, Hailin; Liu, Zhongfan

    2015-09-16

    A novel roll-to-roll, etching-free, clean transfer of CVD-grown graphene from copper to plastic using surface-energy-assisted delamination in hot deionized water is reported. The delamination process is realized by water penetration between the hydrophobic graphene and a hydrophilic native oxide layer on a copper foil.The transferred graphene on plastic is used as a high-output flexible and transparent triboelectric nanogenerator.

  7. A Facile Reduction Method for Roll-to-Roll Production of High Performance Graphene-Based Transparent Conductive Films.

    PubMed

    Ning, Jing; Hao, Long; Jin, Meihua; Qiu, Xiongying; Shen, Yudi; Liang, Jiaxu; Zhang, Xinghao; Wang, Bin; Li, Xianglong; Zhi, Linjie

    2017-03-01

    A facile roll-to-roll method is developed for fabricating reduced graphene oxide (rGO)-based flexible transparent conductive films. A Sn(2+) /ethanol reduction system and a rationally designed fast coating-drying-washing technique are proven to be highly efficient for low-cost continuous production of large-area rGO films and patterned rGO films, extremely beneficial toward the manufacture of flexible photoelectronic devices.

  8. Effects of the microstructure of twin roll cast and hot rolled plates on the surface quality of presensitized plates

    NASA Astrophysics Data System (ADS)

    Zhu, Yuan-Zhi; Zhang, Ya-Feng; Zhao, Chao-Qi; Zhou, Feng

    2014-09-01

    The effect of the microstructure of plates fabricated both in the traditional process, involving casting, hot rolling and cold rolling (HR), and in the novel twin roll casting + cold rolling (TRC) process on the surface quality of presensitized (PS) plates was analyzed by optical microscopy (OM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDXS). The formation of pores on the surface of the electrolyzed HR plate could be attributed to the presence of approximately 1-μm-sized large Al-Fe precipitates in the HR plate compared to the smaller precipitates in the TRC plate. Moreover, residual graphite lubricants used during the TRC process were entrapped on the surface of the TRC plate during the subsequent rolling process. The entrapped pollutants tended to further deteriorate the formation of pores on the surface of the TRC plate, and no residual carbon was detected on the surface of the HR plate. Furthermore, the surface quality of the TRC plate can be improved by surface cleaning before the cold rolling process, which could dramatically lower the residual graphite on the surface.

  9. Continuous roll-to-roll amorphous silicon photovoltaic manufacturing technology. Semiannual subcontract report, 1 April 1993--30 September 1993

    SciTech Connect

    Izu, M

    1994-06-01

    This report describes work for this reporting period under a 3-year program to advance Energy Conversion Device`s (ECD) roll-to-roll, triple-junction photovoltaic (PV) manufacturing technologies, to reduce the module production costs, to increase the stabilized module performance, and to expand commercial production capacity utilizing ECD technology. The specific 3-year goal is to develop advanced large-scale manufacturing technology incorporating ECD`s earlier research advances with the capability of producing modules with stable 11% efficiency at a cost of approximately $1.00 per peak watt. Major accomplishments during this reporting period include (1) the design, construction. amd testomg of a continuous roll-to-roll multipurpose amorphous silicon alloy solar cell deposition machine that incorporates improvements necessary to obtain higher efficiency solar cells; (2) development of a photothermal deflection spectroscopy (PDS) technique for evaluating back-reflector systems; (3) the development of an improved textured Ag/ZnO back-reflector system demonstrating 25% gain in J{sub sc} over previous textured Al back-reflector systems; and (4) the design of a serpentine web continuous roll-to-roll deposition chamber.

  10. Development of a continuous roll-to-roll processing system for mass production of plastic optical film

    NASA Astrophysics Data System (ADS)

    Chang, Chih-Yuan; Tsai, Meng-Hsun

    2015-12-01

    This paper reports a highly effective method for the mass production of large-area plastic optical films with a microlens array pattern based on a continuous roll-to-roll film extrusion and roller embossing process. In this study, a thin steel mold with a micro-circular hole array pattern is fabricated by photolithography and a wet chemical etching process. The thin steel mold was then wrapped onto a metal cylinder to form an embossing roller mold. During the roll-to-roll process operation, a thermoplastic raw material (polycarbonate grains) was put into the barrel of the plastic extruder with a flat T-die. Then, the molten polymer film was extruded and immediately pressed against the surface of the embossing roller mold. Under the proper processing conditions, the molten polymer will just partially fill the micro-circular holes of the mold and due to surface tension form a convex lens surface. A continuous plastic optical film with a microlens array pattern was obtained. Experiments are carried out to investigate the effect of plastic microlens formation on the roll-to-roll process. Finally, the geometrical and optical properties of the fabricated plastic optical film were measured and proved satisfactory. This technique shows great potential for the mass production of large-area plastic optical films with a microlens array pattern.

  11. Reduced Blood Coagulation on Roll-to-Roll, Shrink-Induced Superhydrophobic Plastics.

    PubMed

    Nokes, Jolie M; Liedert, Ralph; Kim, Monica Y; Siddiqui, Ali; Chu, Michael; Lee, Eugene K; Khine, Michelle

    2016-03-09

    The unique antiwetting properties of superhydrophobic (SH) surfaces prevent the adhesion of water and bodily fluids, including blood, urine, and saliva. While typical manufacturable approaches to create SH surfaces rely on chemical and structural modifications, such approaches are expensive, require postprocessing, and are often not biocompatible. By contrast, it is demonstrated that purely structural SH features are easily formed using high throughput roll-to-roll (R2R) manufacturing by shrinking a prestressed thermoplastic with a thin, stiff layer of silver and calcium. These features are subsequently embossed into any commercially available and Food and Drug Administration (FDA)-approved plastic. The R2R SH surfaces have contact angles >150° and contact angle hysteresis <10°. Importantly, the surfaces minimize blood adhesion, leading to reduced blood coagulation without the need for anticoagulants. SH surfaces have >4200× reduction of blood residue area compared to the nonstructured controls of the same material. In addition, blood clotting is reduced >5× using whole blood directly from the patient. Furthermore, these surfaces can be easily configured into 3D shapes, as demonstrated with SH tubes. With the simple scale-up production and the eliminated need for anticoagulants to prevent clotting, the proposed conformable SH surfaces can be impactful for a wide range of medical tools, including catheters and microfluidic channels.

  12. Multivariable passive RFID vapor sensors: roll-to-roll fabrication on a flexible substrate.

    PubMed

    Potyrailo, Radislav A; Burns, Andrew; Surman, Cheryl; Lee, D J; McGinniss, Edward

    2012-06-21

    We demonstrate roll-to-roll (R2R) fabrication of highly selective, battery-free radio frequency identification (RFID) sensors on a flexible polyethylene terephthalate (PET) polymeric substrate. Selectivity of our developed RFID sensors is provided by measurements of their resonance impedance spectra, followed by the multivariate analysis of spectral features, and correlation of these spectral features to the concentrations of vapors of interest. The multivariate analysis of spectral features also provides the ability for the rejection of ambient interferences. As a demonstration of our R2R fabrication process, we employed polyetherurethane (PEUT) as a "classic" sensing material, extruded this sensing material as 25, 75, and 125-μm thick films, and thermally laminated the films onto RFID inlays, rapidly producing approximately 5000 vapor sensors. We further tested these RFID vapor sensors for their response selectivity toward several model vapors such as toluene, acetone, and ethanol as well as water vapor as an abundant interferent. Our RFID sensing concept features 16-bit resolution provided by the sensor reader, granting a highly desired independence from costly proprietary RFID memory chips with a low-resolution analog input. Future steps are being planned for field-testing of these sensors in numerous conditions.

  13. Patterned Immobilization of Antibodies within Roll-to-Roll Hot Embossed Polymeric Microfluidic Channels

    PubMed Central

    Feyssa, Belachew; Liedert, Christina; Kivimaki, Liisa; Johansson, Leena-Sisko; Jantunen, Heli; Hakalahti, Leena

    2013-01-01

    This paper describes a method for the patterned immobilization of capture antibodies into a microfluidic platform fabricated by roll-to-roll (R2R) hot embossing on poly (methyl methacrylate) (PMMA). Covalent attachment of antibodies was achieved by two sequential inkjet printing steps. First, a polyethyleneimine (PEI) layer was deposited onto oxygen plasma activated PMMA foil and further cross-linked with glutaraldehyde (GA) to provide an amine-reactive aldehyde surface (PEI-GA). This step was followed by a second deposition of antibody by overprinting on the PEI-GA patterned PMMA foil. The PEI polymer ink was first formulated to ensure stable drop formation in inkjet printing and the printed films were characterized using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Anti-CRP antibody was patterned on PMMA foil by the developed method and bonded permanently with R2R hot embossed PMMA microchannels by solvent bonding lamination. The functionality of the immobilized antibody inside the microfluidic channel was evaluated by fluorescence-based sandwich immunoassay for detection of C-reactive protein (CRP). The antibody-antigen assay exhibited a good level of linearity over the range of 10 ng/ml to 500 ng/ml (R2 = 0.991) with a calculated detection limit of 5.2 ng/ml. The developed patterning method is straightforward, rapid and provides a versatile approach for creating multiple protein patterns in a single microfluidic channel for multiplexed immunoassays. PMID:23874811

  14. Adaptation of roll-to-roll imprint lithography: from flexible electronics to structural templates

    NASA Astrophysics Data System (ADS)

    Holland, Edward R.; Jeans, Albert; Mei, Ping; Taussig, Carl P.; Elder, Richard E.; Bell, Cynthia; Howard, Emmett; Stowell, John

    2011-04-01

    HP has previously demonstrated the roll-to-roll (R2R) fabrication of active-matrix display backplanes using the Self-Aligned Imprint Lithography (SAIL) process. This approach permits a single imprint step to create a multi level mask comprising all patterns required for subsequent etching steps, obviating the need for multiple alignment steps. In this paper the imprint lithography technique and aspects of SAIL are reviewed. New work using imprint processing to generate structural templates, with aspect ratios approaching 6:1, for fluid containment will be presented. Arrays of transparent well structures, formed on a flexible transparent substrate provide the basis for a color display filter matrix that is filled by inkjet deposition of pigmented resins. A primary benefit of this approach is precise color pattern definition. A separation between primary color fields of 4 microns is realized without risk of color mixing or overlap. Components patterned with high absolute precision by imprint lithography were readily integrated with parts from other sources to yield flexible color reflective display demonstrator panels. This work highlights the flexibility of imprint processing and its suitability for use with a wide variety of materials and in differing applications.

  15. Roll-to-roll embedded conductive structures integrated into organic photovoltaic devices

    NASA Astrophysics Data System (ADS)

    van de Wiel, H. J.; Galagan, Y.; van Lammeren, T. J.; de Riet, J. F. J.; Gilot, J.; Nagelkerke, M. G. M.; Lelieveld, R. H. C. A. T.; Shanmugam, S.; Pagudala, A.; Hui, D.; Groen, W. A.

    2013-12-01

    Highly conductive screen printed metallic (silver) structures (current collecting grids) combined with poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) are a viable replacement for indium tin oxide (ITO) and inkjet printed silver as transparent electrode materials. To provide successful integration into organic photovoltaic (OPV) devices, screen printed silver current collecting grids should be embedded into a substrate to avoid topology issues. In this study micron-thick conductive structures are embedded and integrated into OPV devices. The embedded structures are produced roll-to-roll with optimized process settings and materials. Topology measurements show that the embedded grids are well suited for integration into OPV devices since the surface is almost without spikes and has low surface roughness. JV measurements of OPV devices with embedded structures on a polyethylene terephthalate/silicon nitride (PET/SiN) substrate show an efficiency of 2.15%, which is significantly higher than identical flexible devices with ITO (1.02%) and inkjet printed silver (1.48%). The use of embedded screen printed silver instead of ITO and inkjet printed silver in OPV devices will allow for higher efficiency devices which can be produced with larger design and process freedom.

  16. In-line roll-to-roll metrology for flexible electronics

    NASA Astrophysics Data System (ADS)

    Kimbrough, Brad

    2015-09-01

    The flexible electronics market continues to grow at a rapid pace. Increasing numbers of applications employ the flexible components including displays, biomedical devices, smart apparel, and advanced sensors. To maintain performance and lifetime, many characteristics of the substrate and deposited layers must be monitored. This includes defects, surface roughness, and feature alignment. Ideally, in-situ metrology can be employed in roll-to-roll (R2R) equipment to allow for real-time process control. This presents the necessary three-dimensional metrology system with several challenging requirements: high vertical and transverse resolution, large field-of-view, extremely fast measurement times, and robust vibration immunity. This paper will discuss the design and performance of a compact, low-cost, large-field interferometric probe for in-situ measurement of R2R substrates. Samples with a variety of known and unknown features and roughnesses will be measured to characterize the performance of the system. Static and moving substrates will be measured to examine effects on results. Optimization of processing to allow for on-board analysis will be examined. Lastly, the paper will discuss how such probes may be arrayed to provide a high degree of areal coverage of the flexible substrate under test.

  17. Roll-to-Roll Screen Printed Radio Frequency Identification Transponder Antennas for Vehicle Tracking Systems

    NASA Astrophysics Data System (ADS)

    Zichner, Ralf; Baumann, Reinhard R.

    2013-05-01

    Vehicle tracking systems based on ultra high frequency (UHF) radio frequency identification (RFID) technology are already introduced to control the access to car parks and corporate premises. For this field of application so-called Windshield RFID transponder labels are used, which are applied to the inside of the windshield. State of the art for manufacturing these transponder antennas is the traditional lithography/etching approach. Furthermore the performance of these transponders is limited to a reading distance of approximately 5 m which results in car speed limit of 5 km/h for identification. However, to achieve improved performance compared to existing all-purpose transponders and a dramatic cost reduction, an optimized antenna design is needed which takes into account the special dielectric and in particular metallic car environment of the tag and an roll-to-roll (R2R) printing manufacturing process. In this paper we focus on the development of a customized UHF RFID transponder antenna design, which is adopted for vehicle geometry as well as R2R screen printing manufacturing processes.

  18. Roll-to-roll production of 30-inch graphene films for transparent electrodes

    NASA Astrophysics Data System (ADS)

    Hong, Byung Hee

    2011-03-01

    The outstanding electrical1, mechanical and chemical properties of graphene make it attractive for applications in flexible electronics. However, efforts to make transparent conducting films from graphene have been hampered by the lack of efficient methods for the synthesis, transfer and doping of graphene at the scale and quality required for applications. Here, we report the roll-to-roll production and wet-chemical doping of predominantly monolayer 30-inch graphene films grown by chemical vapour deposition onto flexible copper substrates. The films have sheet resistances as low as ~ 125 Ohm/sq with 97.4% optical transmittance, and exhibit the half-integer quantum Hall effect, indicating their high quality. We further use layer-by-layer stacking to fabricate a doped four-layer film and measure its sheet resistance at values as low as ~ 30 Ohm/sq at ~ 90 % transparency, which is superior to commercial transparent electrodes such as indium tin oxides. Graphene electrodes were incorporated into a fully functional touch-screen panel device capable of withstanding high strain. Work done in collaboration with Sukang Bae, Hyeongkeun Kim, Youngbin Lee, and Jong-Hyun Ahn, Sungkyunkwan University.

  19. Design of an airframe agnostic roll-on/roll-off (AA-RORO) sensor platform

    NASA Astrophysics Data System (ADS)

    Sparks, Bruce; Wowczuk, Zenovy S.; Harrison, A. Jay

    2009-05-01

    The US military has recently taken tactical steps to increase its ISR capabilities to support military operations. Due to the dynamic capabilities of the terrorist threat, there is a need for a payload- and airframe-agnostic, rapid-deployment sensor system that can be used on multiple airframes for in-theater missions and for the test and evaluation of sensors prior to fielding. This "plug-and-play" system, based upon the Oculus Sensor Deployment System technology, uses a system-of-systems approach to modularize the base platform, thereby allowing the system to conform to aircraft such as the C-130, C-27, V-22, CH-47, CH-53 and CASA-235 without any modification to the airframe itself. This type of system can be used as (1) a versatile, cost-effective test and evaluation platform for current and developmental sensors as well as (2) an in-theater ISR asset that can be used on readily available airframes at a particular location. This paper illustrates the CONUS and OCONUS mission potential of this multi-airframe system and outlines the novel design characteristics that the Airframe Agnostic Roll-on/Roll-off (AA-RORO) sensor platform incorporates to make it the most versatile, rapid-deployment sensor platform available to support near-term U.S. military operations. The system concept was developed with the support of and input from multiple military agencies and the respective branches they represent.

  20. Roll-to-Roll Solution-Processible Small-Molecule OLEDs

    SciTech Connect

    Liu, Jie Jerry

    2012-07-31

    The objective of this program is to develop key knowledge and make critical connections between technologies needed to enable low-cost manufacturing of OLED lighting products. In particular, the program was intended to demonstrate the feasibility of making high performance Small-Molecule OLEDs (SM-OLED) using a roll-to-roll (R2R) wet-coating technique by addressing the following technical risks (1) Whether the wet-coating technique can provide high performance OLEDs, (2) Whether SM-OLED can be made in a R2R manner, (3) What are the requirements for coating equipment, and (4) Whether R2R OLEDs can have the same performance as the lab controls. The program has been managed and executed according to the Program Management Plan (PMP) that was first developed at the beginning of the program and further revised accordingly as the program progressed. Significant progress and risk reductions have been accomplished by the end of the program. Specific achievements include: (1) Demonstrated that wet-coating can provide OLEDs with high LPW and long lifetime; (2) Demonstrated R2R OLEDs can be as efficient as batch controls (Figure 1) (3) Developed & validated basic designs for key equipment necessary for R2R SM-OLEDs; (4) Developed know-hows & specifications on materials & ink formulations critical to wetcoating; (5) Developed key R2R processes for each OLED layer (6) Identified key materials and components such as flexible barrier substrates necessary for R2R OLEDs.

  1. Roll-to-roll embedded conductive structures integrated into organic photovoltaic devices.

    PubMed

    van de Wiel, H J; Galagan, Y; van Lammeren, T J; de Riet, J F J; Gilot, J; Nagelkerke, M G M; Lelieveld, R H C A T; Shanmugam, S; Pagudala, A; Hui, D; Groen, W A

    2013-12-06

    Highly conductive screen printed metallic (silver) structures (current collecting grids) combined with poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) are a viable replacement for indium tin oxide (ITO) and inkjet printed silver as transparent electrode materials. To provide successful integration into organic photovoltaic (OPV) devices, screen printed silver current collecting grids should be embedded into a substrate to avoid topology issues. In this study micron-thick conductive structures are embedded and integrated into OPV devices. The embedded structures are produced roll-to-roll with optimized process settings and materials. Topology measurements show that the embedded grids are well suited for integration into OPV devices since the surface is almost without spikes and has low surface roughness. JV measurements of OPV devices with embedded structures on a polyethylene terephthalate/silicon nitride (PET/SiN) substrate show an efficiency of 2.15%, which is significantly higher than identical flexible devices with ITO (1.02%) and inkjet printed silver (1.48%). The use of embedded screen printed silver instead of ITO and inkjet printed silver in OPV devices will allow for higher efficiency devices which can be produced with larger design and process freedom.

  2. Evolution of magnetism by rolling up hexagonal boron nitride nanosheets tailored with superparamagnetic nanoparticles.

    PubMed

    Hwang, Da Young; Choi, Kyoung Hwan; Park, Jeong Eon; Suh, Dong Hack

    2017-02-01

    Controlling tunable properties by rolling up two dimensional nanomaterials is an exciting avenue for tailoring the electronic and magnetic properties of materials at the nanoscale. We demonstrate the tailoring of a magnetic nanocomposite through hybridization with magnetic nanomaterials using hexagonal boron nitride (h-BN) templates as an effective way to evolve magnetism for the first time. Boron nitride nanosheets exhibited their typical diamagnetism, but rolled-up boron nitride sheets (called nanoscrolls) clearly have para-magnetism in the case of magnetic susceptibility. Additionally, the Fe3O4 NP sample shows a maximum ZFC curve at about 103 K, which indicates well dispersed superparamagnetic nanoparticles. The ZFC curve for the h-BN-Fe3O4 NP scrolls exhibited an apparent rounded maximum blocking temperature at 192 K compared to the Fe3O4 NPs, leading to a dramatic increase in TB. These magnetic nanoscroll derivatives are remarkable materials and should be suitable for high-performance composites and nano-, medical- and electromechanical-devices.

  3. Transforming Roving-Rolling Explorer (TRREx) for Planetary Exploration

    NASA Astrophysics Data System (ADS)

    Edwin, Lionel Ernest

    All planetary surface exploration missions thus far have employed traditional rovers with a rocker-bogie suspension. These rovers can navigate moderately rough and flat terrain, but are not designed to traverse rugged terrain with steep slopes. The fact is, however, that many scientifically interesting missions require exploration platforms with capabilities for navigating such types of chaotic terrain. This issue motivates the development of new kinds of rovers that take advantage of the latest advances in robotic technologies to traverse rugged terrain efficiently. This dissertation proposes and analyses one such rover concept called the Transforming Roving-Rolling Explorer (TRREx) that is principally aimed at addressing the above issue. Biologically inspired by the way the armadillo curls up into a ball when threatened, and the way the golden wheel spider uses the dynamic advantages of a sphere to roll down hills when escaping danger, the novel TRREx rover can traverse like a traditional 6-wheeled rover over conventional terrain, but can also transform itself into a sphere, when necessary, to travel down steep inclines, or navigate rough terrain. This work presents the proposed design architecture and capabilities followed by the development of mathematical models and experiments that facilitate the mobility analysis of the TRREx in the rolling mode. The ability of the rover to self-propel in the rolling mode in the absence of a negative gradient increases its versatility and concept value. Therefore, a dynamic model of a planar version of the problem is first used to investigate the feasibility and value of such self-propelled locomotion - 'actuated rolling'. Construction and testing of a prototype Planar/Cylindrical TRREx that is capable of demonstrating actuated rolling is presented, and the results from the planar dynamic model are experimentally validated. This planar model is then built upon to develop a mathematical model of the spherical TRREx in the

  4. Experiments on spray from a rolling tire

    NASA Astrophysics Data System (ADS)

    Radovich, Charles Anthony

    A novel laboratory apparatus has been built to understand the key mechanisms behind spray emerging from a rolling tire. Several researchers have assessed the performance of spray suppression devices; however, there are no known efforts that address the question "what needs to be suppressed?" This investigation into how water in a tire groove evolves into a droplet field will ultimately contribute to driver safety. Using high-speed imaging, water passing through a single circumferential groove was observed to leave the tire patch in the form of a thin liquid sheet, connecting the roadway and the tire. The sheet disintegrates into a droplet field and the breakup modes associated with this decay were identified with respect to Weber number. Weber numbers based on the properties of water, tire speed and tire groove width were tested at 2700, 10900 and 24400. Measurements for the breakup length of the liquid sheet showed a dependence on Weber number proportional to We-1/6. The lateral displacement of the water exiting the tire patch was also measured. These tests showed the overall size of the spray field grows with We; however, the maximum water volume for all We's was delivered to the same distance from the road. Downstream from the tire patch, a determination of the droplet field was performed. From this study, the distribution of droplet sizes was determined as a function of Weber number. At We = 2,700, droplet sizes between 80 and 9000 microm were detected, with a mean diameter near 800 microm. Both the range of droplet sizes and the mean diameter were found to decrease with Weber number by approximately We-1/2. Based on these size distributions, Correlation Image Velocimetry (CIV) was used to estimate the distribution of droplet velocities as function of their size. These results reveal a strong correlation between droplet diameter and velocity which is comparable to that predicted for a simple sphere.

  5. The Foam Roll as a Tool to Improve Hamstring Flexibility.

    PubMed

    Junker, Daniel H; Stöggl, Thomas L

    2015-12-01

    Although foam rolling is a common myofascial therapy used to increase range of motion (ROM), research is limited on the effectiveness of foam rolling on soft tissue extensibility. The aim of this study was to determine the effect of a 4-week training period of the foam roll method on hamstring flexibility. Furthermore, the study was designed to compare the effectiveness of the foam roll myofascial release with a conventional contract-relax proprioceptive neuromuscular facilitation (PNF) stretching method and a control group. Forty healthy males (age: 17-47 years) were randomly assigned to a foam roll group (FOAM, n = 13), a contract-relax PNF stretching group (CRPNF, n = 14), or a control group (CG, n = 13). The FOAM group massaged their hamstring muscles with the foam roll 3 times per week for 4 weeks (12 training sessions). The CRPNF group was assigned to 12 sessions of contract-relax PNF stretching. The CG underwent no intervention. Hamstring flexibility (ROM) was measured by a stand-and-reach test before and after the intervention period. Two-way repeated-measures analysis of variance showed a significant global time effect (p < 0.001) and an interaction effect for time × treatment (p = 0.004), demonstrating greater improvements in the FOAM and CRPNF compared with the CG, but no difference between the former. Delta changes from baseline to postintervention in ROM were not related to baseline ROM. The foam roll can be seen as an effective tool to increase hamstring flexibility within 4 weeks. The effects are comparable with the scientifically proven contract-relax PNF stretching method.

  6. Dimethylsulfoxide exposure modulates HL-60 cell rolling interactions.

    PubMed

    Gee, David J; Wright, L Kate; Zimmermann, Jonathan; Cole, Kayla; Soule, Karen; Ubowski, Michelle

    2012-08-01

    Human leukaemic HL-60 cells are widely used for studying interactions involving adhesion molecules [e.g. P-selectin and PSGL-1 (P-selectin glycoprotein ligand-1)] since their rolling behaviour has been shown to mimic the dynamics of leucocyte rolling in vitro. HL-60 cells are neutrophilic promyelocytes that can undergo granulocytic differentiation upon exposure to compounds such as DMSO (dimethylsulfoxide). Using a parallel plate flow chamber functionalized with recombinant P-selectin-Fc chimaera, undifferentiated and DMSO-induced (48, 72 and 96 h) HL-60 cells were assayed for rolling behaviour. We found that depending on P-selectin incubation concentration, undifferentiated cells incurred up to a 6-fold increase in rolling velocity while subjected to an approximately 10-fold increase in biologically relevant shear stress. HL-60 cells exposed to DMSO for up to 72 h incurred up to a 3-fold increase in rolling velocity over the same shear stress range. Significantly, cells exposed for up to 96 h incurred up to a 9-fold decrease in rolling velocity, compared with undifferentiated HL-60 cells. Although cell surface and nuclear morphological changes were evident upon exposure to DMSO, flow cytometric analysis revealed that PSGL-1 expression was unchanged, irrespective of treatment duration. The results suggest that DMSO-treated HL-60 cells may be problematic as a substitute for neutrophils for trafficking studies during advanced stages of the LAC (leucocyte adhesion cascade). We suggest that remodelling of the cell surface during differentiation may affect rolling behaviour and that DMSO-treated HL-60 cells would behave differently from the normal leucocytes during inflammatory response in vivo.

  7. Dimethylsulfoxide exposure modulates HL-60 cell rolling interactions

    PubMed Central

    Gee, David J.; Wright, L. Kate; Zimmermann, Jonathan; Cole, Kayla; Soule, Karen; Ubowski, Michelle

    2012-01-01

    Human leukaemic HL-60 cells are widely used for studying interactions involving adhesion molecules [e.g. P-selectin and PSGL-1 (P-selectin glycoprotein ligand-1)] since their rolling behaviour has been shown to mimic the dynamics of leucocyte rolling in vitro. HL-60 cells are neutrophilic promyelocytes that can undergo granulocytic differentiation upon exposure to compounds such as DMSO (dimethylsulfoxide). Using a parallel plate flow chamber functionalized with recombinant P-selectin–Fc chimaera, undifferentiated and DMSO-induced (48, 72 and 96 h) HL-60 cells were assayed for rolling behaviour. We found that depending on P-selectin incubation concentration, undifferentiated cells incurred up to a 6-fold increase in rolling velocity while subjected to an approximately 10-fold increase in biologically relevant shear stress. HL-60 cells exposed to DMSO for up to 72 h incurred up to a 3-fold increase in rolling velocity over the same shear stress range. Significantly, cells exposed for up to 96 h incurred up to a 9-fold decrease in rolling velocity, compared with undifferentiated HL-60 cells. Although cell surface and nuclear morphological changes were evident upon exposure to DMSO, flow cytometric analysis revealed that PSGL-1 expression was unchanged, irrespective of treatment duration. The results suggest that DMSO-treated HL-60 cells may be problematic as a substitute for neutrophils for trafficking studies during advanced stages of the LAC (leucocyte adhesion cascade). We suggest that remodelling of the cell surface during differentiation may affect rolling behaviour and that DMSO-treated HL-60 cells would behave differently from the normal leucocytes during inflammatory response in vivo. PMID:22494057

  8. Rolling bearing life models and steel internal cleanliness

    SciTech Connect

    Beswick, J.; Gabelli, A.; Ioannides, S.; Tripp, J.H.; Voskamp, A.P.

    1999-07-01

    The most widely used steel grade for rolling bearings is based on a steel composition first used almost a hundred years ago, the so-called 1C-1.5Cr steel. This steel is used either in a selective surface induction hardened conditions or in a through hardened heat treated condition, both yielding exceptional structural and contact fatigue properties. The Lundberg and Palmgren rolling bearing life prediction model, published in 1947, was the first analytical approach to bearing performance prediction, subsequently becoming a widely accepted basis for rolling bearing life calculations. At that time the fatigue life of rolling bearings was dominated by the classical sub-surface initiated failure mode. This mode results from the accumulation of micro-plastic strain at the depth of maximum Hertzian stress and is accelerated by the stress concentrations occurring at the micro internal defects. In common with all fatigue processes, rolling bearing failure is a statistical process: the failures of bearings with high inclusion content tested at high stress levels belong to the well-known family of Weibull distributions. Steady improvements in bearing steel cleanliness due, amongst other things, to the introduction of secondary metallurgy steel making techniques, have resulted in a significantly increased rolling bearing life and load carrying capacity. In recognition of this, in 1985 Ioannides and Harris introduced a new fatigue life model for rolling bearings, comprising a more widely applicable approach to the modeling of bearing life based on the relevant failure mode. Subsequently this has been extended to include effects of hardness and of micro-inclusion distributions in state-of-the-art clean bearing steel.

  9. Optimum Thread Rolling Process That Improves SCC Resistance

    SciTech Connect

    A.R. Kephart

    2001-10-29

    Accelerated testing in environments aggressive for the specific material have shown that fastener threads that are rolled after strengthening heat treatments have improved resistance to SCC initiation. For example, intergranular SCC was produced in one day when machined (cut) threads of high strength steel (ASTM A193 B-7 and A354 Grade 8) were exposed to an aggressive aqueous environment containing 8 weight % boiling ammonium nitrate and stressed to about 40% of the steel's yield strength (120 ksi, 827 MPa). In similar testing conditions, fasteners that had threads rolled before heat-treatment (quench and temper) had similar susceptibility to SCC. However, threads rolled after strengthening, exhibited no SCC after a week of exposure, even when stressed to 100% of the B-7 alloy yield strength. Similarly, intergranular SCC was produced in less than one day when machined (cut) threads of nickel-base alloys (X-750 and aged 625) were exposed to an aggressive 750 F doped steam environment (containing 100 ppm of chloride, fluoride, sulfate, nitrate and a controlled hydrogen overpressure) and stressed to about 80% of the alloy yield strength (117 ksi, 807 MPa). In similar testing conditions, threads rolled after strengthening exhibited no SCC after 50 days of exposure. This beneficial effect of the optimum thread rolling process (i.e., threads rolled after strengthening) is due to the retention of large residual compressive stresses in the thread roots (notches) which mitigate the applied notch tensile stresses resulting from joint design pre-loads. use of these material specific aggressive environments can provide an accelerated test to verify that threads were produced by the optimum thread rolling process. These tests could support fastener acceptance criteria or failure analysis of fasteners with unknown or uncertain manufacturing processes. The optimum process effects may not always be detected by more conventional methods (e.g., metallography or hardness testing).

  10. Photogrammetric Accuracy and Modeling of Rolling Shutter Cameras

    NASA Astrophysics Data System (ADS)

    Vautherin, Jonas; Rutishauser, Simon; Schneider-Zapp, Klaus; Choi, Hon Fai; Chovancova, Venera; Glass, Alexis; Strecha, Christoph

    2016-06-01

    Unmanned aerial vehicles (UAVs) are becoming increasingly popular in professional mapping for stockpile analysis, construction site monitoring, and many other applications. Due to their robustness and competitive pricing, consumer UAVs are used more and more for these applications, but they are usually equipped with rolling shutter cameras. This is a significant obstacle when it comes to extracting high accuracy measurements using available photogrammetry software packages. In this paper, we evaluate the impact of the rolling shutter cameras of typical consumer UAVs on the accuracy of a 3D reconstruction. Hereto, we use a beta-version of the Pix4Dmapper 2.1 software to compare traditional (non rolling shutter) camera models against a newly implemented rolling shutter model with respect to both the accuracy of geo-referenced validation points and to the quality of the motion estimation. Multiple datasets have been acquired using popular quadrocopters (DJI Phantom 2 Vision+, DJI Inspire 1 and 3DR Solo) following a grid flight plan. For comparison, we acquired a dataset using a professional mapping drone (senseFly eBee) equipped with a global shutter camera. The bundle block adjustment of each dataset shows a significant accuracy improvement on validation ground control points when applying the new rolling shutter camera model for flights at higher speed (8m=s). Competitive accuracies can be obtained by using the rolling shutter model, although global shutter cameras are still superior. Furthermore, we are able to show that the speed of the drone (and its direction) can be solely estimated from the rolling shutter effect of the camera.

  11. The Stiffness Characteristics Study on an Interconnected Anti-Rolling Suspension System

    NASA Astrophysics Data System (ADS)

    Hou, Youshan; Song, Huixin; Ma, Ming; Xiao, Jie; Zhao, Ning

    The heavy-duty special vehicles easily roll during steering, anti-rolling technology becomes a critical technology to the heavy-duty vehicles. Aiming at the rolling problem of a full load heavy vehicle in the process of steering, an interconnected anti-rolling suspension system with adjustable damping was designed, the nonlinear stiffness mathematical model of interconnected anti-rolling suspension system was established. The stiffness characteristic was studied through digital simulation method, discussing the system parameter changes' affection on the stiffness performance of interconnected anti-rolling suspension system. The study results indicate that the interconnected anti-rolling suspension system betterly improves vehicles rolling resistance in contrast to the oil-gas mixed independent suspension, the study results provide theoretical basis for the anti-rolling's design of heavy-duty vehicles.

  12. 78 FR 69371 - Diffusion-Annealed, Nickel-Plated Flat-Rolled Steel Products From Japan: Preliminary...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ... International Trade Administration Diffusion-Annealed, Nickel-Plated Flat-Rolled Steel Products From Japan...-annealed, nickel-plated flat-rolled steel products (certain nickel-plated, flat-rolled steel) from Japan..., nickel-plated flat-rolled steel products included in this investigation are flat-rolled,...

  13. Experimental and theoretical study on minimum achievable foil thickness during asymmetric rolling.

    PubMed

    Tang, Delin; Liu, Xianghua; Song, Meng; Yu, Hailiang

    2014-01-01

    Parts produced by microforming are becoming ever smaller. Similarly, the foils required in micro-machines are becoming ever thinner. The asymmetric rolling technique is capable of producing foils that are thinner than those produced by the conventional rolling technique. The difference between asymmetric rolling and conventional rolling is the 'cross-shear' zone. However, the influence of the cross-shear zone on the minimum achievable foil thickness during asymmetric rolling is still uncertain. In this paper, we report experiments designed to understand this critical influencing factor on the minimum achievable thickness in asymmetric rolling. Results showed that the minimum achievable thickness of rolled foils produced by asymmetric rolling with a rolling speed ratio of 1.3 can be reduced to about 30% of that possible by conventional rolling technique. Furthermore, the minimum achievable thickness during asymmetric rolling could be correlated to the cross-shear ratio, which, in turn, could be related to the rolling speed ratio. From the experimental results, a formula to calculate the minimum achievable thickness was established, considering the parameters cross-shear ratio, friction coefficient, work roll radius, etc. in asymmetric rolling.

  14. Experimental and Theoretical Study on Minimum Achievable Foil Thickness during Asymmetric Rolling

    PubMed Central

    Tang, Delin; Liu, Xianghua; Song, Meng; Yu, Hailiang

    2014-01-01

    Parts produced by microforming are becoming ever smaller. Similarly, the foils required in micro-machines are becoming ever thinner. The asymmetric rolling technique is capable of producing foils that are thinner than those produced by the conventional rolling technique. The difference between asymmetric rolling and conventional rolling is the ‘cross-shear’ zone. However, the influence of the cross-shear zone on the minimum achievable foil thickness during asymmetric rolling is still uncertain. In this paper, we report experiments designed to understand this critical influencing factor on the minimum achievable thickness in asymmetric rolling. Results showed that the minimum achievable thickness of rolled foils produced by asymmetric rolling with a rolling speed ratio of 1.3 can be reduced to about 30% of that possible by conventional rolling technique. Furthermore, the minimum achievable thickness during asymmetric rolling could be correlated to the cross-shear ratio, which, in turn, could be related to the rolling speed ratio. From the experimental results, a formula to calculate the minimum achievable thickness was established, considering the parameters cross-shear ratio, friction coefficient, work roll radius, etc. in asymmetric rolling. PMID:25203265

  15. Finite-element modeling of soft tissue rolling indentation.

    PubMed

    Sangpradit, Kiattisak; Liu, Hongbin; Dasgupta, Prokar; Althoefer, Kaspar; Seneviratne, Lakmal D

    2011-12-01

    We describe a finite-element (FE) model for simulating wheel-rolling tissue deformations using a rolling FE model (RFEM). A wheeled probe performing rolling tissue indentation has proven to be a promising approach for compensating for the loss of haptic and tactile feedback experienced during robotic-assisted minimally invasive surgery (H. Liu, D. P. Noonan, B. J. Challacombe, P. Dasgupta, L. D. Seneviratne, and K. Althoefer, "Rolling mechanical imaging for tissue abnormality localization during minimally invasive surgery, " IEEE Trans. Biomed. Eng., vol. 57, no. 2, pp. 404-414, Feb. 2010; K. Sangpradit, H. Liu, L. Seneviratne, and K. Althoefer, "Tissue identification using inverse finite element analysis of rolling indentation," in Proc. IEEE Int. Conf. Robot. Autom. , Kobe, Japan, 2009, pp. 1250-1255; H. Liu, D. Noonan, K. Althoefer, and L. Seneviratne, "The rolling approach for soft tissue modeling and mechanical imaging during robot-assisted minimally invasive surgery," in Proc. IEEE Int. Conf. Robot. Autom., May 2008, pp. 845-850; H. Liu, P. Puangmali, D. Zbyszewski, O. Elhage, P. Dasgupta, J. S. Dai, L. Seneviratne, and K. Althoefer, "An indentation depth-force sensing wheeled probe for abnormality identification during minimally invasive surgery," Proc. Inst. Mech. Eng., H, vol. 224, no. 6, pp. 751-63, 2010; D. Noonan, H. Liu, Y. Zweiri, K. Althoefer, and L. Seneviratne, "A dual-function wheeled probe for tissue viscoelastic property identification during minimally invasive surgery," in Proc. IEEE Int. Conf. Robot. Autom. , 2008, pp. 2629-2634; H. Liu, J. Li, Q. I. Poon, L. D. Seneviratne, and K. Althoefer, "Miniaturized force indentation-depth sensor for tissue abnormality identification," IEEE Int. Conf. Robot. Autom., May 2010, pp. 3654-3659). A sound understanding of wheel-tissue rolling interaction dynamics will facilitate the evaluation of signals from rolling indentation. In this paper, we model the dynamic interactions between a wheeled probe and a

  16. Phenomena of Foamed Concrete under Rolling of Aircraft Wheels

    NASA Astrophysics Data System (ADS)

    Jiang, Chun-shui; Yao, Hong-yu; Xiao, Xian-bo; Kong, Xiang-jun; Shi, Ya-jie

    2014-04-01

    Engineered Material Arresting System (EMAS) is an effective technique to reduce hazards associated with aircraft overrunning runway. In order to ascertain phenomena of the foamed concrete used for EMAS under rolling of aircraft wheel, a specially designed experimental setup was built which employed Boeing 737 aircraft wheels bearing actual vertical loads to roll through the foamed concrete. A number of experiments were conducted upon this setup. It is discovered that the wheel rolls the concrete in a pure rolling manner and crushes the concrete downwards, instead of crushing it forward, as long as the concrete is not higher than the wheel axle. The concrete is compressed into powder in-situ by the wheel and then is brought to bottom of the wheel. The powder under the wheel is loose and thus is not able to sustain wheel braking. It is also found that after being rolled by the wheel the concrete exhibits either of two states, i.e. either 'crushed through' whole thickness of the concrete or 'crushed halfway', depending on combination of strength of the concrete, thickness of the concrete, vertical load the wheel carries, tire dimension and tire pressure. A new EMAS design concept is developed that if an EMAS design results in the 'crushed through' state for the main gears while the 'crushed halfway' state for the nose gear, the arresting bed would be optimal to accommodate the large difference in strength between the nose gear and the main gear of an aircraft.

  17. Rolling Motions During Solar Prominence Eruptions in Asymmetric Magnetic Environments

    NASA Astrophysics Data System (ADS)

    McKillop, Sean; Miralles, Mari Paz; Murphy, Nicholas Arnold; McCauley, Patrick

    2014-06-01

    Panasenco et al. [1] report observations of several CMEs that display a rolling motion about the axis of the erupting prominence. Murphy et al. [2] present simulations of line-tied asymmetric magnetic reconnection that make a falsifiable prediction regarding the handedness of rolling motions of flux ropes during solar eruptions. We will present initial results of our work to investigate this prediction. To determine the strength and any asymmetric properties of the magnetic field in the regions of interest in the photosphere, we use magnetograms from HMI. We use AIA observations to determine if there is any rolling motion and, if so, what handedness the rolling motions have. We then compare the photospheric magnetic information with the handedness information to determine if there is any relationship between the two. Finally, we will discuss prospects for diagnosing rolling motions of erupting prominence using off-limb IRIS observations.[1] O. Panasenco, S. Martin, A. D. Joshi, & N. Srivastava, J. Atmos. Sol.-Terr. Phys., 73, 1129 (2011)[2] N. A. Murphy, M. P. Miralles, C. L. Pope, J. C. Raymond, H. D. Winter, K. K. Reeves, D. B. Seaton, A. A. van Ballegooijen, & J. Lin, ApJ, 751, 56 (2012)

  18. Twisting/Rolling Motions and Chirality in Filament Eruptions

    NASA Astrophysics Data System (ADS)

    McKillop, S.; Murphy, N. A.; Miralles, M. P.; McCauley, P.; Su, Y.

    2015-12-01

    Panasenco et al. [1] report observations of several CMEs that display a rolling motion about the axis of the erupting prominence. Murphy et al. [2] present simulations of line-tied asymmetric magnetic reconnection that make a falsifiable prediction regarding the handedness of rolling motions of flux ropes during solar eruptions. Mass motions in prominence eruptions tend to be complicated, and characterizing these motions is a challenge. We use the AIA filament eruption catalog [3] as a source for finding events. If rolling motions are detected then we will investigate the handedness prediction. We use magnetograms from HMI to determine the strength and asymmetric properties of the photospheric magnetic field in the regions of interest and will use AIA observations to determine the handedness of the rolling motions. We then compare the photospheric magnetic information with the handedness to determine if there is a relationship between the two. The AIA filament eruption catalog is a great source for finding events, but it lacks a chirality determination. We aim to add these determinations and then compare the chirality with the directionality of the twisting/rolling motions. [1] O. Panasenco, S. Martin, A. D. Joshi, & N. Srivastava, J. Atmos. Sol.-Terr. Phys., 73, 1129 (2011) [2] N. A. Murphy, M. P. Miralles, C. L. Pope, J. C. Raymond, H. D. Winter, K. K. Reeves, D. B. Seaton, A. A. van Ballegooijen, & J. Lin, ApJ, 751, 56 (2012) [3] http://aia.cfa.harvard.edu/filament/

  19. CMB quadrupole suppression. II. The early fast roll stage

    NASA Astrophysics Data System (ADS)

    Boyanovsky, D.; de Vega, H. J.; Sanchez, N. G.

    2006-12-01

    Within the effective field theory of inflation, an initialization of the classical dynamics of the inflaton with approximate equipartition between the kinetic and potential energy of the inflaton leads to a brief fast roll stage that precedes the slow roll regime. The fast roll stage leads to an attractive potential in the wave equations for the mode functions of curvature and tensor perturbations. The evolution of the inflationary perturbations is equivalent to the scattering by this potential and a useful dictionary between the scattering data and observables is established. Implementing methods from scattering theory we prove that this attractive potential leads to a suppression of the quadrupole moment for CMB and B-mode angular power spectra. The scale of the potential is determined by the Hubble parameter during slow roll. Within the effective field theory of inflation at the grand unification (GUT) energy scale we find that if inflation lasts a total number of e-folds Ntot˜59, there is a 10% 20% suppression of the CMB quadrupole and about 2% 4% suppression of the tensor quadrupole. The suppression of higher multipoles is smaller, falling off as 1/l2. The suppression is much smaller for Ntot>59, therefore if the observable suppression originates in the fast roll stage, there is the upper bound Ntot˜59.

  20. On the sound radiation of a rolling tyre

    NASA Astrophysics Data System (ADS)

    Kropp, Wolfgang; Sabiniarz, Patrick; Brick, Haike; Beckenbauer, Thomas

    2012-04-01

    The sound radiation from rolling tyres is still not very well understood. Although details such as horn effect or directivity during rolling have been investigated, it is not clear which vibrational modes of the tyre structure are responsible for the radiated sound power. In this work an advanced tyre model based on Wave Guide Finite Elements is used in connection with a contact model validated in previous work. With these tools the tyre vibrations during rolling on an ISO surface are simulated. Starting from the calculated contact forces in time the amplitudes of the modes excited during rolling are determined as function of frequency. A boundary element model also validated in previous work is applied to predict the sound pressure level on a reference surface around a tyre placed on rigid ground as function of the modal composition of the tyre vibrations. Taking into account different modes when calculating the vibrational field as input into the boundary element calculations, it is possible to identify individual modes or groups of modes of special relevance for the radiated sound power. The results show that mainly low-order modes with relative low amplitudes but high radiation efficiency in the frequency range around 1 kHz are responsible for the radiated sound power at these frequencies, while those modes which are most strongly excited in that frequency range during rolling are irrelevant for the radiated sound power. This fact is very essential when focusing on the design of quieter tyres.

  1. Study of texture, microstructure and mechanical properties of asymmetrically rolled aluminium

    NASA Astrophysics Data System (ADS)

    Wronski, M.; Wierzbanowski, K.; Wronski, S.; Bacroix, B.; Wróbel, M.; Uniwersał, A.

    2015-04-01

    Asymmetric rolling is a promising forming technique offering numerous possibilities of material properties modification and the improvement of technological process parameters. This geometry of deformation is relatively easy to implement on existing industrial rolling mills. Moreover, it can provide large volume of a material with modified properties. The study of microstructure, crystallographic texture and mechanical properties of asymmetrically rolled aluminium is presented in this work. The above characteristics were examined using EBSD technique and X-ray diffraction. The rolling asymmetry was realized using two identical rolls, driven by independent motors, rotating with different angular velocities. It was found that asymmetric rolling leads to microstructure refinement, texture homogenization and decreasing of residual stress.

  2. Bioinspired superhydrophobic surfaces, fabricated through simple and scalable roll-to-roll processing

    PubMed Central

    Park, Sung-Hoon; Lee, Sangeui; Moreira, David; Bandaru, Prabhakar R.; Han, InTaek; Yun, Dong-Jin

    2015-01-01

    A simple, scalable, non-lithographic, technique for fabricating durable superhydrophobic (SH) surfaces, based on the fingering instabilities associated with non-Newtonian flow and shear tearing, has been developed. The high viscosity of the nanotube/elastomer paste has been exploited for the fabrication. The fabricated SH surfaces had the appearance of bristled shark skin and were robust with respect to mechanical forces. While flow instability is regarded as adverse to roll-coating processes for fabricating uniform films, we especially use the effect to create the SH surface. Along with their durability and self-cleaning capabilities, we have demonstrated drag reduction effects of the fabricated films through dynamic flow measurements. PMID:26490133

  3. A Flight Investigation of the Damping in Roll and Rolling Effectiveness Including Aeroelastic Effects of Rocket Propelled Missile Models Having Cruciform, Triangular, Interdigitated Wings and Tails

    NASA Technical Reports Server (NTRS)

    Hopko, R. N.

    1951-01-01

    The damping in roll and rolling effectiveness of two models of a missile having cruciform, triangular, interdigitated wings and tails have been determined through a Mach number range of 0.8 to 1.8 by utilizing rocket-propelled test vehicles. Results indicate that the damping in roll was relatively constant over the Mach umber range investigated. The rolling effectiveness was essentially constant at low supersonic speeds and increased with increasing mach numbers in excess of 1.4 over the Mach number range investigated. Aeroelastic effects increase the rolling-effectiveness parameters pb/2V divided by delta and decrease both the rolling-moment coefficient due to wing deflection and the damping-in-roll coefficient.

  4. Characterization of printed planar electromagnetic coils using digital extrusion and roll-to-roll flexographic processes

    NASA Astrophysics Data System (ADS)

    Rickard, Scott

    Electromagnets are a crucial component in a wide range of more complex electrical devices due to their ability to turn electrical energy into mechanical energy and vice versa. The trend for electronics becoming smaller and lighter has led to increased interest in using flat, planar electromagnetic coils, which have been shown to perform better at scaled down sizes. The two-dimensional geometry of a planar electromagnetic coil yields itself to be produced by a roll-to-roll additive manufacturing process. The emergence of the printed electronics field, which uses traditional printing processes to pattern functional inks, has led to new methods of mass-producing basic electrical components. The ability to print a planar electromagnetic coil using printed electronics could rival the traditional subtractive and semi-subtractive PCB process of manufacturing. The ability to print lightweight planar electromagnetic coils on flexible substrates could lead to their inclusion into intelligent packaging applications and could have specific use in actuating devices, transformers, and electromagnetic induction applications such as energy harvesting or wireless charging. In attempts to better understand the limitations of printing planar electromagnetic coils, the effect that the design parameters of the planar coils have on the achievable magnetic field strength were researched. A comparison between prototyping methods of digital extrusion and manufacturing scale flexographic printing are presented, discussing consistency in the printed coils and their performance in generating magnetic fields. A method to predict the performance of these planar coils is introduced to allow for design within required needs of an application. Results from the research include a demonstration of a printed coil being used in a flat speaker design, working off of actuating principles.

  5. Flow behavior of polymers during the roll-to-roll hot embossing process

    NASA Astrophysics Data System (ADS)

    Deng, Yujun; Yi, Peiyun; Peng, Linfa; Lai, Xinmin; Lin, Zhongqin

    2015-06-01

    The roll-to-roll (R2R) hot embossing process is a recent advancement in the micro hot embossing process and is capable of continuously fabricating micro/nano-structures on polymers, with a high efficiency and a high throughput. However, the fast forming of the R2R hot embossing process limits the time for material flow and results in complicated flow behavior in the polymers. This study presents a fundamental investigation into the flow behavior of polymers and aims towards the comprehensive understanding of the R2R hot embossing process. A three-dimensional (3D) finite element (FE) model based on the viscoelastic model of polymers is established and validated for the fabrication of micro-pyramids using the R2R hot embossing process. The deformation and recovery of micro-pyramids on poly(vinyl chloride) (PVC) film are analyzed in the filling stage and the demolding stage, respectively. Firstly, in the analysis of the filling stage, the temperature distribution on the PVC film is discussed. A large temperature gradient is observed along the thickness direction of the PVC film and the temperature of the top surface is found to be higher than that of the bottom surface, due to the poor thermal conductivity of PVC. In addition, creep strains are demonstrated to depend highly on the temperature and are also observed to concentrate on the top layer of the PVC film because of high local temperature. In the demolding stage, the recovery of the embossed micro-pyramids is obvious. The cooling process is shown to be efficient for the reduction of recovery, especially when the mold temperature is high. In conclusion, this research advances the understanding of the flow behavior of polymers in the R2R hot embossing process and might help in the development of the highly accurate and highly efficient fabrication of microstructures on polymers.

  6. Roll-to-roll atomic layer deposition process for flexible electronics encapsulation applications

    SciTech Connect

    Maydannik, Philipp S. Kääriäinen, Tommi O.; Lahtinen, Kimmo; Cameron, David C.; Söderlund, Mikko; Soininen, Pekka; Johansson, Petri; Kuusipalo, Jurkka; Moro, Lorenza; Zeng, Xianghui

    2014-09-01

    At present flexible electronic devices are under extensive development and, among them, flexible organic light-emitting diode displays are the closest to a large market deployment. One of the remaining unsolved challenges is high throughput production of impermeable flexible transparent barrier layers that protect sensitive light-emitting materials against ambient moisture. The present studies deal with the adaptation of the atomic layer deposition (ALD) process to high-throughput roll-to-roll production using the spatial ALD concept. We report the development of such a process for the deposition of 20 nm thickness Al{sub 2}O{sub 3} diffusion barrier layers on 500 mm wide polymer webs. The process uses trimethylaluminum and water as precursors at a substrate temperature of 105 °C. The observation of self-limiting film growth behavior and uniformity of thickness confirms the ALD growth mechanism. Water vapor transmission rates for 20 nm Al{sub 2}O{sub 3} films deposited on polyethylene naphthalate (PEN) substrates were measured as a function of substrate residence time, that is, time of exposure of the substrate to one precursor zone. Moisture permeation levels measured at 38 °C/90% relative humidity by coulometric isostatic–isobaric method were below the detection limit of the instrument (<5 × 10{sup −4} g/m{sup 2} day) for films coated at web moving speed of 0.25 m/min. Measurements using the Ca test indicated water vapor transmission rates ∼5 × 10{sup −6} g/m{sup 2} day. Optical measurements on the coated web showed minimum transmission of 80% in the visible range that is the same as the original PEN substrate.

  7. Modeling of rolling element bearing mechanics. Computer program user's manual

    NASA Technical Reports Server (NTRS)

    Greenhill, Lyn M.; Merchant, David H.

    1994-01-01

    This report provides the user's manual for the Rolling Element Bearing Analysis System (REBANS) analysis code which determines the quasistatic response to external loads or displacement of three types of high-speed rolling element bearings: angular contact ball bearings, duplex angular contact ball bearings, and cylindrical roller bearings. The model includes the defects of bearing ring and support structure flexibility. It is comprised of two main programs: the Preprocessor for Bearing Analysis (PREBAN) which creates the input files for the main analysis program, and Flexibility Enhanced Rolling Element Bearing Analysis (FEREBA), the main analysis program. This report addresses input instructions for and features of the computer codes. A companion report addresses the theoretical basis for the computer codes. REBANS extends the capabilities of the SHABERTH (Shaft and Bearing Thermal Analysis) code to include race and housing flexibility, including such effects as dead band and preload springs.

  8. Effects of surface removal on rolling-element fatigue

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.

    1987-01-01

    The Lundberg-Palmgren equation was modified to show the effect on rolling-element fatigue life of removing by grinding a portion of the stressed volume of the raceways of a rolling-element bearing. Results of this analysis show that depending on the amount of material removed, and depending on the initial running time of the bearing when material removal occurs, the 10-percent life of the reground bearings ranges from 74 to 100 percent of the 10-percent life of a brand new bearing. Three bearing types were selected for testing. A total of 250 bearings were reground. Of this matter, 30 bearings from each type were endurance tested to 1600 hr. No bearing failure occurred related to material removal. Two bearing failures occurred due to defective rolling elements and were typical of those which may occur in new bearings.

  9. TECHNICAL NOTE Rolling dielectric elastomer actuator with bulged cylindrical shape

    NASA Astrophysics Data System (ADS)

    Potz, Marco; Artusi, Matteo; Soleimani, Maryam; Menon, Carlo; Cocuzza, Silvio; Debei, Stefano

    2010-12-01

    This note presents preliminary investigations on the design and development of a rolling dielectric elastomer actuator (rDEA) with a bulged cylindrical shape. The actuator is based on an inflated silicone-based hollow cylinder consisting of a series of dielectric elastomer actuator sectors. The electrical activation of the sectors changes the shape of the rDEA; the induced geometrical change causes a variation of the position of the rDEA's centre of gravity and a consequent initiation of rolling of the rDEA. This paper presents a simplified parametric analytical model which is used to simulate the quasi-static behaviour of the rDEA. A testing procedure is used to assess the potential rolling performance of the rDEA prototypes.

  10. Roll-up of validation results to a target application.

    SciTech Connect

    Hills, Richard Guy

    2013-09-01

    Suites of experiments are preformed over a validation hierarchy to test computational simulation models for complex applications. Experiments within the hierarchy can be performed at different conditions and configurations than those for an intended application, with each experiment testing only part of the physics relevant for the application. The purpose of the present work is to develop methodology to roll-up validation results to an application, and to assess the impact the validation hierarchy design has on the roll-up results. The roll-up is accomplished through the development of a meta-model that relates validation measurements throughout a hierarchy to the desired response quantities for the target application. The meta-model is developed using the computation simulation models for the experiments and the application. The meta-model approach is applied to a series of example transport problems that represent complete and incomplete coverage of the physics of the target application by the validation experiments.

  11. Main roll for an air press of a papermaking machine

    DOEpatents

    Beck, David A.

    2004-03-09

    A roll for use in an air press assembly of a papermaking machine has a pair of ends associated therewith. The roll includes a pair of edge portions with each edge portion extending to one of the pair of ends. Each edge portion has an edge surface portion composed of a first material, the first material having a first hardness. The roll further includes a middle portion located between the pair of edge portions, the middle portion having a middle surface portion composed of a second material. The second material has a second hardness, the second material being harder than the first material. The first material is preferably a soft, seal material which promotes reduced air leakage from the air press assembly.

  12. Traction forces at solid-lubricated rolling/sliding contacts

    NASA Technical Reports Server (NTRS)

    Aggarwal, B. B.; Bovenkerk, R. L.

    1985-01-01

    A single-element traction rig was used to measure the traction forces at a solid-lubricated contact of a ball against a flat disk at room temperature under combine rolling and sliding. The load and speed conditions were selected to match those anticipated for bearing applications in adiabatic diesel engines. Traction vs slide/roll ratio curves were similar to those for liquid lubricants but the traction forces were an order of magnitude higher. The test data were used to derive equations to predict traction force as a function of contact stress and rolling speed. The data showed that the magnitude of traction forces were almost the same for all the lubricants tested. The lubricants, should, therefore, be selected on the basis of their ability to limit the wear of contact surfaces.

  13. Heat generation in Aircraft tires under yawed rolling conditions

    NASA Technical Reports Server (NTRS)

    Dodge, Richard N.; Clark, Samuel K.

    1987-01-01

    An analytical model was developed for approximating the internal temperature distribution in an aircraft tire operating under conditions of yawed rolling. The model employs an assembly of elements to represent the tire cross section and treats the heat generated within the tire as a function of the change in strain energy associated with predicted tire flexure. Special contact scrubbing terms are superimposed on the symmetrical free rolling model to account for the slip during yawed rolling. An extensive experimental program was conducted to verify temperatures predicted from the analytical model. Data from this program were compared with calculation over a range of operating conditions, namely, vertical deflection, inflation pressure, yaw angle, and direction of yaw. Generally the analytical model predicted overall trends well and correlated reasonably well with individual measurements at locations throughout the cross section.

  14. Dynamical states in the sensorimotor loop of a rolling robot

    NASA Astrophysics Data System (ADS)

    Sándor, Bulcsú; Jahn, Tim; Martin, Laura; Echeveste, Rodrigo; Gros, Claudius

    We investigate the closed sensorimotor loop of a simple rolling robot as a dynamical system. Using the LpzRobots simulation package, we construct robots with cylindrical body, controlled by a single proprioceptual neuron with a time dependent threshold. Despite its simplicity, we obtain a rich set of rolling modes, as a result of the self-organizing processes arising through the feedback within the sensorimotor loop. These rolling modes are robust against environmental noise, since they correspond to stable limit cycle attractors. However, for certain parameters they also allow for explorative behavior via internal noise induced switching. Furthermore, we also find a region of parameters in which the motion is fully embodied, where, in engineering terms, the engine powering the motion of the robot is turned on dynamically through the feedback of its very motion.

  15. Modeling of rolling element bearing mechanics. Theoretical manual

    NASA Technical Reports Server (NTRS)

    Merchant, David H.; Greenhill, Lyn M.

    1994-01-01

    This report documents the theoretical basis for the Rolling Element Bearing Analysis System (REBANS) analysis code which determines the quasistatic response to external loads or displacement of three types of high-speed rolling element bearings: angular contact ball bearings; duplex angular contact ball bearings; and cylindrical roller bearings. The model includes the effects of bearing ring and support structure flexibility. It is comprised of two main programs: the Preprocessor for Bearing Analysis (PREBAN) which creates the input files for the main analysis program; and Flexibility Enhanced Rolling Element Bearing Analysis (FEREBA), the main analysis program. A companion report addresses the input instructions for and features of the computer codes. REBANS extends the capabilities of the SHABERTH (Shaft and Bearing Thermal Analysis) code to include race and housing flexibility, including such effects as dead band and preload springs.

  16. Differential speed rolling of twin-roll-cast 6xxx al alloy strips and its influence on the sheet formability

    NASA Astrophysics Data System (ADS)

    Son, Seong-Guk; Kim, Hong-Kyu; Cho, Jae-Hyung; Kim, Hyung-Wook; Lee, Jae-Chul

    2016-01-01

    We demonstrate the feasibility of a technique that combines twin-roll strip casting, asymmetric rolling, and subsequent heat treatment, in obtaining Al alloy sheets with high-strength/high-formability. The precipitation- hardening Al alloy sheet thus obtained exhibited an excellent formability (bar r= 1.20, Δ r = 0.17) and mechanical properties (σTS = 265 MPa, ɛ = 35%), which cannot be readily obtained via the conventional route based on direct-chill casting and heavy rolling operation. In this study, we examined the effects of the various process conditions used at different stages of the process that contribute to the development of specific textures. Simulation studies based on the generalized spherical harmonic series expansion method and the viscoplastic self-consistent (VPSC) model were conducted to arrive at a comprehensive understanding of the factors associated with the high formability realized in Al alloy sheet. It was found that specific textures evolved via twin-roll strip casting, asymmetric rolling, and heat treatment canceled out the anisotropic characteristics of the individual textures, resulting in the high sheet formability.

  17. Human Ocular Counter-Rolling and Roll Tilt Perception during Off-Vertical Axis Rotation after Spaceflight

    NASA Technical Reports Server (NTRS)

    Clement, Gilles; Denise, Pierre; Reschke, Millard; Wood, Scott J.

    2007-01-01

    Ocular counter-rolling (OCR) induced by whole body tilt in roll has been explored after spaceflight as an indicator of the adaptation of the otolith function to microgravity. It has been claimed that the overall pattern of OCR responses during static body tilt after spaceflight is indicative of a decreased role of the otolith function, but the results of these studies have not been consistent, mostly due to large variations in the OCR within and across individuals. By contrast with static head tilt, off-vertical axis rotation (OVAR) presents the advantage of generating a sinusoidal modulation of OCR, allowing averaged measurements over several cycles, thus improving measurement accuracy. Accordingly, OCR and the sense of roll tilt were evaluated in seven astronauts before and after spaceflight during OVAR at 45 /s in darkness at two angles of tilt (10 and 20 ). There was no significant difference in OCR during OVAR immediately after landing compared to preflight. However, the amplitude of the perceived roll tilt during OVAR was significantly larger immediately postflight, and then returned to control values in the following days. Since the OCR response is predominantly attributed to the shearing force exerted on the utricular macula, the absence of change in OCR postflight suggests that the peripheral otolith organs function normally after short-term spaceflight. However, the increased sense of roll tilt indicates an adaptation in the central processing of gravitational input, presumably related to a re-weigthing of the internal representation of gravitational vertical as a result of adaptation to microgravity.

  18. Static roll-tilt over 5 minutes locally distorts the internal estimate of direction of gravity.

    PubMed

    Tarnutzer, A A; Bockisch, C J; Straumann, D; Marti, S; Bertolini, G

    2014-12-01

    The subjective visual vertical (SVV) indicates perceived direction of gravity. Even in healthy human subjects, roll angle-dependent misestimations, roll overcompensation (A-effect, head-roll > 60° and <135°) and undercompensation (E-effect, head-roll < 60°), occur. Previously, we demonstrated that, after prolonged roll-tilt, SVV estimates when upright are biased toward the preceding roll position, which indicates that perceived vertical (PV) is shifted by the prior tilt (Tarnutzer AA, Bertolini G, Bockisch CJ, Straumann D, Marti S. PLoS One 8: e78079, 2013). Hypothetically, PV in any roll position could be biased toward the previous roll position. We asked whether such a "global" bias occurs or whether the bias is "local". The SVV of healthy human subjects (N = 9) was measured in nine roll positions (-120° to +120°, steps = 30°) after 5 min of roll-tilt in one of two adaptation positions (±90°) and compared with control trials without adaptation. After adapting, adjustments were shifted significantly (P < 0.05) toward the previous adaptation position for nearby roll-tilted positions (±30°, ±60°) and upright only. We computationally simulated errors based on the sum of a monotonically increasing function (producing roll undercompensation) and a mixture of Gaussian functions (representing roll overcompensation centered around PV). In combination, the pattern of A- and E-effects could be generated. By shifting the function representing local overcompensation toward the adaptation position, the experimental postadaptation data could be fitted successfully. We conclude that prolonged roll-tilt locally distorts PV rather than globally shifting it. Short-term adaptation of roll overcompensation may explain these shifts and could reflect the brain's strategy to optimize SVV estimates around recent roll positions. Thus postural stability can be improved by visually-mediated compensatory responses at any sustained body-roll orientation.

  19. Note on the stability of viscous roll waves

    NASA Astrophysics Data System (ADS)

    Barker, Blake; Johnson, Mathew A.; Noble, Pascal; Rodrigues, Luis Miguel; Zumbrun, Kevin

    2017-02-01

    In this note, we announce a complete classification of the stability of periodic roll-wave solutions of the viscous shallow water equations, from their onset at Froude number F ≈ 2 up to the infinite Froude limit. For intermediate Froude numbers, we obtain numerically a particularly simple power-law relation between F and the boundaries of the region of stable periods, which appears potentially useful in hydraulic engineering applications. In the asymptotic regime F → 2 (onset), we provide an analytic expression of the stability boundaries, whereas in the limit F → ∞, we show that roll waves are always unstable.

  20. Rolling contact fatigue of various unfilled and fiber reinforced polymers

    NASA Astrophysics Data System (ADS)

    Almajid, Abdulhakim; Friedrich, Klaus

    2012-07-01

    The wear behavior of Polyamide 6 (PA6), Polyoxymethylene (POM), Polyetheretherketone (PEEK), and Polyparaphenylene (PPP) materials under rolling contact was investigated. The ball on plate principle, i.e. a steel ball (as counterpart) rolls on a polymer plate specimen in rotational or linear motion, was used. The results are shown for different stress parameters which vary by load (50 N up to 300 N) and testing time (up to 50 hours). Differences in surface fatigue mechanisms were illustrated by microscopic methods. The best performance was found for PEEK. All the neat polymers were superior to any reinforced versions of them.

  1. Hybrid bearing technology for advanced turbomachinery: Rolling contact fatigue testing

    SciTech Connect

    Dill, J.F.

    1996-01-01

    The purpose of this paper is to describe the basic structure and results to date of a major ARPA funded effort to provide a tribological performance database on ceramic bearing materials and their interaction with standard bearing steels. Program efforts include studies of material physical properties, machining characteristics, and tribological performance. The majority of the testing completed to date focuses on rolling contact fatigue testing of the ceramic materials, including efforts to arrive at optimum approaches to evaluating ceramic/steel hybrid combinations in rolling contact fatigue.

  2. Note: A 1-m Foucault pendulum rolling on a ball

    NASA Astrophysics Data System (ADS)

    Salva, H. R.; Benavides, R. E.; Venturino, J. A.; Cuscueta, D. J.; Ghilarducci, A. A.

    2013-10-01

    We have built a short Foucault pendulum of 1-m length. The aim of this work was to increase the sensitivity to elliptical trajectories from other longer pendula. The design was a semi-rigid pendulum that rolls over a small ball. The measurements of the movements (azimuth and elliptical trajectory) were done by an optical method. The resulting pendulum works in a medium satisfactory way due to problems of the correct choice of the mass of the bob together with the diameter of the supporting ball. It is also important to keep the rolling surface very clean.

  3. Left-handedness and tongue-rolling ability.

    PubMed

    Fry, C J

    1988-08-01

    948 undergraduates at The Ohio State University were administered the 10-item Edinburgh Handedness Inventory and asked to indicate the extent to which they could turn up the sides of their tongues. Significantly fewer left-handers than right-handers (62.8% and 74.8%, respectively) reported being able to turn up either or both sides. Sex differences in tongue-rolling ability were also noted. Among the 403 men included in the final sample, 77.4% could roll their tongues, whereas only 69.7% of the 491 women could do so.

  4. Note: A 1-m Foucault pendulum rolling on a ball.

    PubMed

    Salva, H R; Benavides, R E; Venturino, J A; Cuscueta, D J; Ghilarducci, A A

    2013-10-01

    We have built a short Foucault pendulum of 1-m length. The aim of this work was to increase the sensitivity to elliptical trajectories from other longer pendula. The design was a semi-rigid pendulum that rolls over a small ball. The measurements of the movements (azimuth and elliptical trajectory) were done by an optical method. The resulting pendulum works in a medium satisfactory way due to problems of the correct choice of the mass of the bob together with the diameter of the supporting ball. It is also important to keep the rolling surface very clean.

  5. Plain and Rolled Images from Paired Fingerprint Cards

    National Institute of Standards and Technology Data Gateway

    NIST Plain and Rolled Images from Paired Fingerprint Cards (PC database for purchase)   NIST Special Database 29 is being distributed for use in development and testing fingerprint matching systems. The data consist of 216 ten-print fingerprint card pairs with both the rolled and plains (from a bottom of the fingerprint card) scanned at 19.7 pixels per mm. A newer version of the compression/decompression software on the CDROM can be found at the website http://www.nist.gov/itl/iad/ig/nigos.cfm as part of the NBIS package.

  6. Isothermal Roll Forging of T55 Compressor Blades

    DTIC Science & Technology

    1977-12-01

    with: (1) high strength at the blade forging temperature ; (2) good resistance to deformation and fracture when repeatedly cycled to the forging...feedstock, having lower room temperature strength, buckled under the same load resulting in only partial fill of the dies. The high force (6000 lb...Flash Control 16 3.1.5 Roll Forge Atmosphere 15 3.1.6 Roll Forge Lubricant 17 3.1.7 Temperature Control 17 3.2 Task 2 - Process Selection 18 3.3 Task

  7. An electrically injected rolled-up semiconductor tube laser

    SciTech Connect

    Dastjerdi, M. H. T.; Djavid, M.; Mi, Z.

    2015-01-12

    We have demonstrated electrically injected rolled-up semiconductor tube lasers, which are formed when a coherently strained InGaAs/InGaAsP quantum well heterostructure is selectively released from the underlying InP substrate. The device exhibits strong coherent emission in the wavelength range of ∼1.5 μm. A lasing threshold of ∼1.05 mA is measured for a rolled-up tube with a diameter of ∼5 μm and wall thickness of ∼140 nm at 80 K. The Purcell factor is estimated to be ∼4.3.

  8. The Relationship Between Hot and Cold Rolling Parameters and Secondary Recrystallization Behavior in Silicon Steel Sheets

    NASA Astrophysics Data System (ADS)

    Jahangiri, Mohammadreza

    2015-08-01

    The effect of different hot and cold rolling process variables was evaluated for the secondary recrystallization behavior of silicon steel sheets, and a simple model was developed. On the basis of the model, the following results can be drawn: (a) for complete secondary recrystallization of silicon steel sheets, rolling of cast ingots must precede MnS precipitation start; (b) if it is necessitated, intermediate annealing during hot rolling passes must be carried out in the temperature of about 1000 °C; (c) during hot rolling, the amount of initial strain before the intermediate annealing of rolled strips at 1000 °C must be >70% reduction in thickness; (d) in the two-stage cold rolling method, the thickness reduction in the second cold rolling stage must be <61%; and (e) secondary recrystallization is encouraged by using the non-conventional three-stage cold rolling method with two intermediate anneals.

  9. 76 FR 36870 - Special Conditions: Gulfstream Model GVI Airplane; Design Roll Maneuver Requirement for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-23

    ...; Design Roll Maneuver Requirement for Electronic Flight Controls AGENCY: Federal Aviation Administration... electronic flight control system that provides roll control of the airplane through pilot inputs to the flight computers. These special conditions contain the additional safety standards that the...

  10. Microstructure and texture of asymmetrically rolled aluminium and titanium after deformation and recrystallization

    NASA Astrophysics Data System (ADS)

    Wronski, M.; Wierzbanowski, K.; Wronski, S.; Bacroix, B.

    2015-08-01

    Asymmetric rolling is used to modify material properties and to reduce forces and torques applied during deformation. This geometry of deformation is relatively easy to implement on existing industrial rolling mills and it can provide large volumes of a material. The results of the study of microstructure and crystallographic texture in asymmetrically rolled aluminium 6061 and titanium (grade 2) are presented in this work. These characteristics were determined using the EBSD technique and X-ray diffraction. The rolling asymmetry was realized using two identical rolls, driven by independent motors, rotating with different angular velocities. It was found that asymmetric rolling leads to microstructural refinement and texture rotation (around the transverse direction). The impact of asymmetric rolling on microstructural refinement appears also in recrystallized samples of both materials. On the other hand, texture rotation, caused by asymmetric rolling, persists after annealing in titanium but not in aluminium samples.

  11. Effect of skin-pass rolling direction on magnetic properties of semiprocessed nonoriented electrical steel sheets

    SciTech Connect

    Kurosaki, Y.; Shimazu, T.; Shiozaki, M.

    1999-09-01

    Effect of skin-pass rolling direction on magnetic properties and directionality in semiprocessed nonoriented electrical steel sheets produced by skin-pass rolling process was studied. Skin-pass rolling direction greatly affects magnetic properties and directionality. By control of skin-pass rolling direction, the value of B{sub 50} in the required directions such as 0{degree}, 90{degree} and circumferential direction can be adjusted and the value of B{sub 50} is higher than that of the usual skin-pass rolling direction of 0{degree}. The textures of the steel sheets developed after batch annealing varied with the skin-pass rolling directions and this result indicates that the residual strain energy by skin-pass rolling varies with skin-pass rolling directions.

  12. 77 FR 13483 - Airworthiness Directives; Rolls-Royce plc (RR) Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-07

    ... Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, England, DE248BJ; phone: 011-44-1332..., contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, England, DE248BJ; phone:...

  13. 78 FR 11976 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-21

    ... information identified in this AD, contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby... Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, England, DE248BJ; phone:...

  14. Ultrashort-pulsed laser processing and solution based coating in roll-to-roll manufacturing of organic photovoltaics

    NASA Astrophysics Data System (ADS)

    Hördemann, C.; Hirschfelder, K.; Schaefer, M.; Gillner, A.

    2015-09-01

    The breakthrough of flexible organic electronics and especially organic photovoltaics is highly dependent on cost-efficient production technologies. Roll-2-Roll processes show potential for a promising solution in terms of high throughput and low-cost production of thin film organic components. Solution based material deposition and integrated laser patterning processes offer new possibilities for versatile production lines. The use of flexible polymeric substrates brings along challenges in laser patterning which have to be overcome. One main challenge when patterning transparent conductive layers on polymeric substrates are material bulges at the edges of the ablated area. Bulges can lead to short circuits in the layer system leading to device failure. Therefore following layers have to have a sufficient thickness to cover and smooth the ridge. In order to minimize the bulging height, a study has been carried out on transparent conductive ITO layers on flexible PET substrates. Ablation results using different beam shapes, such as Gaussian beam, Top-Hat beam and Donut-shaped beam, as well as multi-pass scribing and double-pulsed ablation are compared. Furthermore, lab scale methods for cleaning the patterned layer and eliminating bulges are contrasted to the use of additional water based sacrificial layers in order to obtain an alternative procedure suitable for large scale Roll-2-Roll manufacturing. Besides progress in research, ongoing transfer of laser processes into a Roll-2-Roll demonstrator is illustrated. By using fixed optical elements in combination with a galvanometric scanner, scribing, variable patterning and edge deletion can be performed individually.

  15. Design of a novel 5-DOF flexure-based compound alignment stage for Roll-to-Roll Printed Electronics.

    PubMed

    Chen, Weihai; Yang, Shang; Liu, Jingmeng; Chen, Wenjie; Jin, Yan

    2017-02-01

    Alignment stage is a pivotal component for Roll-to-Roll Printed Electronic (R2RPE), especially for Roll-to-Roll inkjet printing. This paper presents the design, modeling, and testing of a new flexure-based compound alignment stage for R2RPE. In this design, the alignment stage has 5-DOF (Degree of Freedom) motions for compensating the alignment errors and only the rotation motion about the y-axis is redundant. The stage is constructed in series by four key parts and adopts a compounded flexure structure to achieve a great performance. Each part is driven by a piezoelectric actuator or voice coil motor actuator to obtain one or two DOF motion. In order to enlarge the travel range of the alignment stage, a Scott-Russell mechanism and a lever mechanism are arranged in series for forming a two-grade displacement amplifier to overcome the small displacement of the actuator. Based on the pseudo-rigid-body simplification method, alignment models are developed. Kinematic and static analyses are conducted to evaluate the performance of the stage in terms of travel range and input stiffness. Finite element simulation is carried out to examine the mechanical performance and the theoretical models. A prototype is fabricated and experiments are conducted. Results show that the proposed alignment stage possesses an error compensation workspace of 148.11μm×149.73μm×813.61μm×1.558mrad×3.501mrad with output coupling errors of 0.693% and 0.637% between the x- and y-axis, which meets the requirements of Roll-to-Roll inkjet printing.

  16. Design of a novel 5-DOF flexure-based compound alignment stage for Roll-to-Roll Printed Electronics

    NASA Astrophysics Data System (ADS)

    Chen, Weihai; Yang, Shang; Liu, Jingmeng; Chen, Wenjie; Jin, Yan

    2017-02-01

    Alignment stage is a pivotal component for Roll-to-Roll Printed Electronic (R2RPE), especially for Roll-to-Roll inkjet printing. This paper presents the design, modeling, and testing of a new flexure-based compound alignment stage for R2RPE. In this design, the alignment stage has 5-DOF (Degree of Freedom) motions for compensating the alignment errors and only the rotation motion about the y-axis is redundant. The stage is constructed in series by four key parts and adopts a compounded flexure structure to achieve a great performance. Each part is driven by a piezoelectric actuator or voice coil motor actuator to obtain one or two DOF motion. In order to enlarge the travel range of the alignment stage, a Scott-Russell mechanism and a lever mechanism are arranged in series for forming a two-grade displacement amplifier to overcome the small displacement of the actuator. Based on the pseudo-rigid-body simplification method, alignment models are developed. Kinematic and static analyses are conducted to evaluate the performance of the stage in terms of travel range and input stiffness. Finite element simulation is carried out to examine the mechanical performance and the theoretical models. A prototype is fabricated and experiments are conducted. Results show that the proposed alignment stage possesses an error compensation workspace of 148.11 μ m ×149.73 μ m × 813.61 μ m × 1.558 mrad × 3.501 mrad with output coupling errors of 0.693% and 0.637% between the x- and y-axis, which meets the requirements of Roll-to-Roll inkjet printing.

  17. An experimental study on the induced rolling moment due to wing-tail interference and roll-controllable two-stage rocket

    NASA Astrophysics Data System (ADS)

    Shirouzu, M.; Soga, K.; Yamazaki, T.; Shibato, Y.; Akimoto, T.

    1983-12-01

    A wind tunnel investigation of a roll-controllable two-stage rocket model was made at free-stream Mach numbers from 0.5 to 2.5. The model has ailerons on front-fins to generate rolling moment and free-rolling tail-fins to eliminate the effect of the induced rolling moment on tail-fins. The results confirmed the feasibility of this type of roll-controllable rocket. The characteristics of the induced rolling moment were investigated by tests of a model with fixed tail-fins. The characteristics were compared with theoretical results based on the strip-theory. Values of roll-damping coefficient of the tail-fins were obtained by analyzing their rolling rate. The effect of the free-rolling tail-fins on other aerodynamic characteristics, such as normal force coefficient, center of pressure and axial force coefficient were also evaluated. A computer simulation of the rolling motion of the TT-500A rocket, which has a similar configuration to the present model, was made based on the results of the present study, whose results agreed well with the flight-data.

  18. The Rolling Friction of Several Airplane Wheels and Tires and the Effect of Rolling Friction on Take-Off

    NASA Technical Reports Server (NTRS)

    Wetmore, J W

    1937-01-01

    This report presents the results of test made to determine the rolling friction of airplane wheels and tires under various conditions of wheel loading, tire inflation pressure, and ground surface. The effect of wheel-bearing type was also investigated. Six pairs of wheels and tires were tested including two sizes of each of the types designated as standard (high pressure), low pressure, and extra low pressure. The results of calculations intended to show the effect of variations in rolling friction on take-off are also presented.

  19. Dye-less color filter fabricated by roll-to-roll imprinting for liquid crystal display applications.

    PubMed

    Lin, Hui-Hsiung; Lee, Chi-Hung; Lu, Mao-Hong

    2009-07-20

    A diffractive grating is promising for color separation to effectively replace conventional absorptive dye color filter in liquid crystal displays. In this paper, we demonstrated a color separation module consisting of an aspheric-lenticular lens array and a blazed grating to substitute for the dye color filter. Each component was designed to match the recent fabrication ability of our roll-to-roll imprinting. The measurement results of a prototype module showed a gain factor of transmission efficiency three times more than that of conventional color filters.

  20. Strain analysis of plasma CVD graphene for roll-to-roll production by scanning transmission electron microscopy and Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Kato, Ryuichi; Koga, Yoshinori; Matsuishi, Kiyoto; Hasegawa, Masataka

    2017-03-01

    The establishment of the roll-to-roll CVD is one of the key factors for realizing the commercial application of graphene. The strain in graphene synthesized by high-throughput plasma CVD using two different conditions related to growth rate and tension to the substrate is analyzed by scanning transmission electron microscopy (STEM) and Raman spectroscopy. The compressive strain generated during the growth by the tension to the substrate and the difference in thermal expansion coefficient between the graphene and the copper substrate is observed, which affects electrical conductivity. It was confirmed by STEM observation that no particularly large strain was accumulated at grain boundaries and their surroundings.

  1. 40 CFR 1066.225 - Roll runout and diameter verification procedure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... section. (2) Measure roll diameter using a Pi Tape®. Orient the Pi Tape® to the marker line at the desired measurement location with the Pi Tape® hook pointed outward. Temporarily secure the Pi Tape® to the roll near the hook end with adhesive tape. Slowly turn the roll, wrapping the Pi Tape® around the roll...

  2. 40 CFR 1066.225 - Roll runout and diameter verification procedure.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... section. (2) Measure roll diameter using a Pi Tape®. Orient the Pi Tape® to the marker line at the desired measurement location with the Pi Tape® hook pointed outward. Temporarily secure the Pi Tape® to the roll near the hook end with adhesive tape. Slowly turn the roll, wrapping the Pi Tape® around the roll...

  3. Aqueous processing of low-band-gap polymer solar cells using roll-to-roll methods.

    PubMed

    Andersen, Thomas R; Larsen-Olsen, Thue T; Andreasen, Birgitta; Böttiger, Arvid P L; Carlé, Jon E; Helgesen, Martin; Bundgaard, Eva; Norrman, Kion; Andreasen, Jens W; Jørgensen, Mikkel; Krebs, Frederik C

    2011-05-24

    Aqueous nanoparticle dispersions of a series of three low-band-gap polymers poly[4,8-bis(2-ethylhexyloxy)benzo(1,2-b:4,5-b')dithiophene-alt-5,6-bis(octyloxy)-4,7-di(thiophen-2-yl)(2,1,3-benzothiadiazole)-5,5'-diyl] (P1), poly[(4,4'-bis(2-ethylhexyl)dithieno[3,2-b:2',3'-d]silole)-2,6-diyl-alt-(2,1,3-benzothiadiazole)-4,7-diyl] (P2), and poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (P3) were prepared using ultrasonic treatment of a chloroform solution of the polymer and [6,6]-phenyl-C(61)-butyric acid methyl ester ([60]PCBM) mixed with an aqueous solution of sodium dodecylsulphate (SDS). The size of the nanoparticles was established using small-angle X-ray scattering (SAXS) of the aqueous dispersions and by both atomic force microscopy (AFM) and using both grazing incidence SAXS (GISAXS) and grazing incidence wide-angle X-ray scattering (GIWAXS) in the solid state as coated films. The aqueous dispersions were dialyzed to remove excess detergent and concentrated to a solid content of approximately 60 mg mL(-1). The formation of films for solar cells using the aqueous dispersion required the addition of the nonionic detergent FSO-100 at a concentration of 5 mg mL(-1). This enabled slot-die coating of high quality films with a dry thickness of 126 ± 19, 500 ± 25, and 612 ± 22 nm P1, P2, and P3, respectively for polymer solar cells. Large area inverted polymer solar cells were thus prepared based on the aqueous inks. The power conversion efficiency (PCE) reached for each of the materials was 0.07, 0.55, and 0.15% for P1, P2, and P3, respectively. The devices were prepared using coating and printing of all layers including the metal back electrodes. All steps were carried out using roll-to-roll (R2R) slot-die and screen printing methods on flexible substrates. All five layers were processed using environmentally friendly methods and solvents. Two of the layers were processed entirely from water (the electron transport layer and the active

  4. 77 FR 16917 - Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ... Deutschland Ltd & Co KG Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final... information identified in this AD, contact Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, Dahlewitz, 15827... Rolls-Royce Deutschland Ltd & Co KG (Formerly Rolls-Royce plc, Derby, England): Amendment...

  5. Computer-aided analysis and design of the shape rolling process for producing turbine engine airfoils

    NASA Technical Reports Server (NTRS)

    Lahoti, G. D.; Akgerman, N.; Altan, T.

    1978-01-01

    Mild steel (AISI 1018) was selected as model cold-rolling material and Ti-6Al-4V and INCONEL 718 were selected as typical hot-rolling and cold-rolling alloys, respectively. The flow stress and workability of these alloys were characterized and friction factor at the roll/workpiece interface was determined at their respective working conditions by conducting ring tests. Computer-aided mathematical models for predicting metal flow and stresses, and for simulating the shape-rolling process were developed. These models utilize the upper-bound and the slab methods of analysis, and are capable of predicting the lateral spread, roll-separating force, roll torque and local stresses, strains and strain rates. This computer-aided design (CAD) system is also capable of simulating the actual rolling process and thereby designing roll-pass schedule in rolling of an airfoil or similar shape. The predictions from the CAD system were verified with respect to cold rolling of mild steel plates. The system is being applied to cold and hot isothermal rolling of an airfoil shape, and will be verified with respect to laboratory experiments under controlled conditions.

  6. 21 CFR 136.180 - Whole wheat bread, rolls, and buns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... statement of ingredients prescribed for bread, rolls and buns by § 136.110, except that: (1) The dough is... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Whole wheat bread, rolls, and buns. 136.180... § 136.180 Whole wheat bread, rolls, and buns. (a) Each of the foods whole wheat bread, graham...

  7. 21 CFR 136.180 - Whole wheat bread, rolls, and buns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... statement of ingredients prescribed for bread, rolls and buns by § 136.110, except that: (1) The dough is... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Whole wheat bread, rolls, and buns. 136.180... § 136.180 Whole wheat bread, rolls, and buns. (a) Each of the foods whole wheat bread, graham...

  8. Roll compaction process modeling: transfer between equipment and impact of process parameters.

    PubMed

    Souihi, Nabil; Reynolds, Gavin; Tajarobi, Pirjo; Wikström, Håkan; Haeffler, Gunnar; Josefson, Mats; Trygg, Johan

    2015-04-30

    In this study, the roll compaction of an intermediate drug load formulation was performed using horizontally and vertically force fed roll compactors. The horizontally fed roll compactor was equipped with an instrumented roll technology allowing the direct measurement of normal stress at the roll surface, while the vertically fed roll compactor was equipped with a force gauge between the roll axes. Furthermore, characterization of ribbons, granules and tablets was also performed. Ribbon porosity was primarily found to be a function of normal stress, exhibiting a quadratic relationship thereof. A similar quadratic relationship was also observed between roll force and ribbon porosity of the vertically fed roll compactor. The predicted peak pressure (Pmax) using the Johanson model was found to be higher than the measured normal stress, however, the predicted Pmax correlated well with the ribbon relative density/porosity and the majority of downstream properties of granules and tablets, demonstrating its use as a scale-independent parameter. A latent variable model was developed for both the horizontal and vertical fed roll compactors to express ribbon porosity as a function of geometric and process parameters. The model validation, performed with new data, resulted in overall good predictions. This study successfully demonstrated the scale up/transfer between two different roll compactors and revealed that the combined use of design of experiments, latent variable models and in silico predictions result in better understanding of the critical process parameters in roll compaction.

  9. Simple Model of a Rolling Water-Filled Bottle on an Inclined Ramp

    ERIC Educational Resources Information Center

    Lin, Shihao; Hu, Naiwen; Yao, Tianchen; Chu, Charles; Babb, Simona; Cohen, Jenna; Sangiovanni, Giana; Watt, Summer; Weisman, Danielle; Klep, James; Walecki, Wojciech J.; Walecki, Eve S.; Walecki, Peter S.

    2015-01-01

    We investigate a water-filled bottle rolling down an incline and ask the following question: is a rolling bottle better described by a model ignoring all internal motion where the bottle is approximated by a material point sliding down an incline, or is it better described by a rigid solid cylinder rolling down the incline without skidding? The…

  10. 75 FR 61114 - Airworthiness Directives; Rolls-Royce plc RB211-Trent 800 Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-04

    ... Directives; Rolls-Royce plc RB211-Trent 800 Series Turbofan Engines AGENCY: Federal Aviation Administration.... Fax: (202) 493-2251. Contact Rolls-Royce plc, P.O. Box 31, Derby, England, DE248BJ; telephone: 011-44... proposed AD, for Rolls- Royce plc RB211-Trent 800 series turbofan engines. That proposed AD would...

  11. 40 CFR 426.30 - Applicability; description of the rolled glass manufacturing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... rolled glass manufacturing subcategory. 426.30 Section 426.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Rolled Glass Manufacturing Subcategory § 426.30 Applicability; description of the rolled...

  12. 40 CFR 426.30 - Applicability; description of the rolled glass manufacturing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... rolled glass manufacturing subcategory. 426.30 Section 426.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Rolled Glass Manufacturing Subcategory § 426.30 Applicability; description of the rolled...

  13. 40 CFR 426.30 - Applicability; description of the rolled glass manufacturing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... rolled glass manufacturing subcategory. 426.30 Section 426.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Rolled Glass Manufacturing Subcategory § 426.30 Applicability; description of the rolled...

  14. Raising the Reliability of Forming Rolls by Alloying Their Core with Copper

    NASA Astrophysics Data System (ADS)

    Zhizhkina, N. A.

    2016-11-01

    The mechanical properties and the structure of forming rolls from cast irons of different compositions are studied. A novel iron including a copper additive that lowers its chilling and raises the homogeneity of the structure is suggested for the roll cores. The use of such iron should raise the reliability of the rolls in operation.

  15. Rock and Roll English Teaching: Content-Based Cultural Workshops

    ERIC Educational Resources Information Center

    Robinson, Tim

    2011-01-01

    In this article, the author shares a content-based English as a Second/Foreign Language (ESL/EFL) workshop that strengthens language acquisition, increases intrinsic motivation, and bridges cultural divides. He uses a rock and roll workshop to introduce an organizational approach with a primary emphasis on cultural awareness content and a…

  16. Role of micropillar arrays in cell rolling dynamics.

    PubMed

    Kim, Kisoo; Koo, Junemo; Moon, SangJun; Lee, Won Gu

    2016-12-19

    In this study, we present a role of arrayed micropillar structures in cell rolling dynamics. Cell rolling on a ligand coated surface as a means of cell separation was demonstrated using a micropillar-integrated microfluidic channel. This approach allows the separation of cells according to characteristic surface properties, regardless of cell size. In these experiments, different moving trajectories of the cells between a ligand-coated micropost structure and a 1% BSA coated micropost structure were observed using sequential images. Based on the analysis of the angle of travel of cells in the trajectory, the average angles of travel on the ligand-coated microposts were 1.5° and -3.1° on a 1% BSA-coated micropost structure. The overall force equivalent applied to a cell can be analyzed to predict the cell rolling dynamics when a cell is detached. These results show that it will be possible to design chip geometry for delicate operations and to separate target cells. Furthermore, we believe that these control techniques based on a ligand coated micropillar surface can be used for enhancing cell rolling-based separation in a faster and more continuous manner.

  17. Interior detail of a rolling door and the pivot windows ...

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

    Interior detail of a rolling door and the pivot windows in the south side bay. View facing east northeast - U.S. Naval Base, Pearl Harbor, Shipfitter's Shop, Seventh Street near Avenue C, Adjacent to Repair Basins, Pearl City, Honolulu County, HI

  18. 14 CFR 25.491 - Taxi, takeoff and landing roll.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.491 Taxi, takeoff and landing roll. Within the range of appropriate ground speeds and approved weights, the airplane... aircraft is operating over the roughest ground that may reasonably be expected in normal operation....

  19. 14 CFR 25.491 - Taxi, takeoff and landing roll.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.491 Taxi, takeoff and landing roll. Within the range of appropriate ground speeds and approved weights, the airplane... aircraft is operating over the roughest ground that may reasonably be expected in normal operation....

  20. 14 CFR 25.491 - Taxi, takeoff and landing roll.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.491 Taxi, takeoff and landing roll. Within the range of appropriate ground speeds and approved weights, the airplane... aircraft is operating over the roughest ground that may reasonably be expected in normal operation....

  1. A numerical method for vortex sheet roll-up

    NASA Technical Reports Server (NTRS)

    Krasny, R.

    1986-01-01

    The problem of computing vortex sheet roll-up from periodic analytic initial data is studied. Previous theoretical and numerical work is reviewed. Computational difficulties arising from ill posedness and singularity formation are discussed. A desingularization method is proposed to diminish these difficulties. Computations indicate that this approach converges past the time at which previous numerical investigations have failed to converge.

  2. On trajectories of rolling marbles in cones and other funnels

    NASA Astrophysics Data System (ADS)

    White, Gary D.

    2013-12-01

    We report on theoretical and experimental results for a ball that rolls without slipping on a surface of revolution, whose symmetry axis is aligned with a uniform gravitational field, particularly investigating both near-circular orbits and scattering-type orbits in cones. The experimental data give support for the theoretical treatment, a non-trivial application of Newton's second law that expands on our previous work and related work of others. Our findings refine those from a recent article in this journal, and largely replicate those obtained from an earlier Lagrangian approach, adding some new details and commentary. While the orbits of marbles rolling in cones do not match inverse-square-law orbits quantitatively (e.g., instead of Kepler's 3rd law, we have T2∝R), we argue that students should experience these qualitative phenomena—precession of orbits, escape velocity behavior, spin-orbit coupling, conservation laws for angular momentum, energy, and spin projection—as much for the fun and kinesthetic impressions as for the raw learning. We also report on a heretofore largely ignored variable in the exploration of rolling orbits in a gravity well: the marble's spin about its own axis as it rolls. Experimenters can, intentionally or not, vary this initial condition and produce different orbital periods for a given orbital radius—a distinctly non-celestial behavior. Careful selection of the initial spin direction and speed for a particular cone can result in marble orbits that mimic the planetary ellipses.

  3. The Locus of the Focus of a Rolling Parabola

    ERIC Educational Resources Information Center

    Agarwal, Anurag; Marengo, James

    2010-01-01

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

  4. Oblique view to the northwest detailing four overhead rolling doors ...

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

    Oblique view to the northwest detailing four overhead rolling doors on the northeast elevation - Over-the-Horizon Backscatter Radar Network, Mountain Home Air Force Operations Building, On Desert Street at 9th Avenue Mountain Home Air Force Base, Mountain Home, Elmore County, ID

  5. Modelling of horizontal centrifugal casting of work roll

    NASA Astrophysics Data System (ADS)

    Xu, Zhian; Song, Nannan; Tol, Rob Val; Luan, Yikun; Li, Dianzhong

    2012-07-01

    A numerical model to simulate horizontal centrifugal roll castings is presented in this paper. In order to simulate the flow fluid and solidification of horizontal centrifugal roll casting correctly, the model uses a body fitted mesh technique to represent the geometry. This new method maps a plate layer mesh to a circular mesh. The smooth body fitted mesh method gives more accurate calculation results for cylindrical geometries. A velocity depending on the angular velocity and inner radius of the mould is set up as a velocity boundary condition. The fluid flow coupled with heat transfer and solidification in a rapidly rotating roll is simulated. A gravity free falling method is applied as a pouring condition. A moveable pouring system is also used in the simulations. High speed steel is used to produce the work roll. Two different gating positions and a moveable gating system are simulated in this paper. Results show that the position of pouring system has a significant influence on the temperature distribution. The temperature distribution at a fixed central pouring system is more favourable than the distribution from a side pouring system. A moving gating system method is a better way to obtain a uniform temperature field in centrifugal casting and offers an alternative for existing techniques.

  6. Reduction of ocular counter-rolling by adaptation to space

    NASA Technical Reports Server (NTRS)

    Dai, Mingjia; Mcgarvie, Leigh; Kozlovskaya, Inessa; Sirota, Mischa; Raphan, Theodore; Cohen, Bernard

    1993-01-01

    We studied the three-dimensional vestibulo-ocular reflex (VOR) of rhesus monkeys before and after the COSMOS Biosatellite 2229 Mission of 1992-1993. This included tests of ocular counter-rolling (OCR), the gain of the vestibulo-ocular reflex (VOR), and spatial orientation of velocity storage. A four-axis vestibular and oculomotor stimulator was transported to the Institute of Biomedical Problems in Moscow for the pre- and postflight ground-based testing. Twelve normal juvenile male rhesus monkey were implanted surgically with eye coils and tested 60-90 days before spaceflight. Two monkey (7906 and 6151), selected from the twelve as flight animals, flew from 12/29/92 to 1/10/93. Upon recovery, they were tested for 11 days postflight along with three control animals. Compensatory ocular torsion was produced in two ways: (1) Lateral head tilts evoked OCR through otolith-ocular reflexes. OCR was also measured dynamically during off-vertical axis rotation (OVAR). (2) Rotation about a naso-occipital axis that was either vertical of horizontal elicited torsional nystagmus through semicircular canal-ocular reflexes (roll VOR). OCR from the otoliths was substantially reduced (70 percent) for 11 days after reentry on both modes of testing. The gain of the roll VOR was also decreased, but less than OCR. These data demonstrate that there was a long-lasting depression of torsional or roll eye movements after adaptation to microgravity in these monkeys, especially those movements produced by the otolith organs.

  7. Magnetoresistance of rolled-up Fe3Si nanomembranes

    NASA Astrophysics Data System (ADS)

    Schumann, J.; Lisunov, K. G.; Escoffier, W.; Raquet, B.; Broto, J. M.; Arushanov, E.; Mönch, I.; Makarov, D.; Deneke, C.; Schmidt, O. G.

    2012-06-01

    Magnetotransport of individual rolled-up Fe3Si nanomembranes is investigated in a broad temperature range from 4.2 K up to 300 K in pulsed magnetic fields up to 55 T. The observed magnetoresistance (MR) has the following pronounced features: (i) MR is negative in the investigated intervals of temperature and magnetic field; (ii) its magnitude increases linearly with the magnetic field in a low-field region and reveals a gradual trend to saturation when the magnetic field increases; (iii) the MR effect becomes more pronounced with increasing temperature. These dependences of MR on the magnetic field and temperature are in line with predictions of the spin-disorder model of the spin-flip s-d interaction assisted with creation or annihilation of magnons, which is expected above a certain critical temperature. Comparison of the MR features in rolled-up and planar samples reveals a substantial increase of the critical temperature in the rolled-up tube, which is attributed to a new geometry and internal strain arising in the rolled-up nanomembranes, influencing the electronic and magnetic properties of the material.

  8. Rolling adhesion kinematics of yeast engineered to express selectins.

    PubMed

    Bhatia, Sujata K; Swers, Jeffrey S; Camphausen, Raymond T; Wittrup, K Dane; Hammer, Daniel A

    2003-01-01

    Selectins are cell adhesion molecules that mediate capture of leukocytes on vascular endothelium as an essential component of the inflammatory response. Here we describe a method for yeast surface display of selectins, together with a functional assay that measures rolling adhesion of selectin-expressing yeast on a ligand-coated surface. E-selectin-expressing yeast roll specifically on surfaces bearing sialyl-Lewis-x ligands. Observation of yeast rolling dynamics at various stages of their life cycle indicates that the kinematics of yeast motion depends on the ratio of the bud radius to the parent radius (B/P). Large-budded yeast "walk" across the surface, alternately pivoting about bud and parent. Small-budded yeast "wobble" across the surface, with bud pivoting about parent. Tracking the bud location of budding yeast allows measurement of the angular velocity of the yeast particle. Comparison of translational and angular velocities of budding yeast demonstrates that selectin-expressing cells are rolling rather than slipping across ligand-coated surfaces.

  9. Rolling resistance of electric vehicle tires from track tests

    NASA Technical Reports Server (NTRS)

    Dustin, M. O.; Slavik, R. J.

    1982-01-01

    Special low-rolling-resistance tires were made for DOE's ETV-1 electric vehicle. Tests were conducted on these tires and on a set of standard commercial automotive tires to determine the rolling resistance as a function of time during both constant-speed tires and SAE J227a driving cycle tests. The tests were conducted on a test track at ambient temperatures that ranged from 15 to 32 C (59 to 89 F) and with tire pressures of 207 to 276 kPa (30 to 40 psi). At a contained-air temperature of 38 C (100 F) and a pressure of 207 kPa (30 psi) the rolling resistances of the electric vehicle tires and the standard commercial tires, respectively, were 0.0102 and 0.0088 kilogram per kilogram of vehicle weight. At a contained-air temperature of 38 C (100 F) and a pressure of 276 kPa (40 psi) the rolling resistances were 0.009 and 0.0074 kilogram per kilogram of vehicle weight, respectively.

  10. In-situ conditioning of a strip casting roll

    DOEpatents

    Williams, Robert S.; Campbell, Steven L.

    1997-01-01

    A strip caster (10) for producing a continuous strip (24) has a tundish (12) for containing a melt (14) and a pair of horizontally disposed water cooled casting rolls (22). The casting rolls are juxtaposed relative to one another for forming a pouring basin (18) for receiving the melt through a teeming tube (16) thereby establishing a meniscus (20) between the rolls for forming a strip (24). The melt is protected from the outside air by a non-oxidizing gas passed through a supply line (28) to a sealing chamber (26). Devices (29) for conditioning the outer peripheral chill surfaces of the casting rolls includes grit blasting nozzles (30A, 30B, 30C, 30D), a collection trough (32) for gathering the grit, a line (34) for recycling the grit to a bag house (36), a feeder (38) and a pressurized distributor (40) for delivering the grit to the nozzles. The conditioning nozzles remove dirt, metal oxides and surface imperfections providing a clean surface readily wetted by the melt.

  11. In-situ conditioning of a strip casting roll

    DOEpatents

    Williams, R.S.; Campbell, S.L.

    1997-07-29

    A strip caster (10) for producing a continuous strip (24) has a tundish (12) for containing a melt (14) and a pair of horizontally disposed water cooled casting rolls (22). The casting rolls are juxtaposed relative to one another for forming a pouring basin (18) for receiving the melt through a teeming tube (16) thereby establishing a meniscus (20) between the rolls for forming a strip (24). The melt is protected from the outside air by a non-oxidizing gas passed through a supply line (28) to a sealing chamber (26). Devices (29) for conditioning the outer peripheral chill surfaces of the casting rolls includes grit blasting nozzles (30A, 30B, 30C, 30D), a collection trough (32) for gathering the grit, a line (34) for recycling the grit to a bag house (36), a feeder (38) and a pressurized distributor (40) for delivering the grit to the nozzles. The conditioning nozzles remove dirt, metal oxides and surface imperfections providing a clean surface readily wetted by the melt.

  12. #43 HOT ROLL, A TWOHIGH REVERSING MILL THAT PRODUCES THE ...

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

    #43 HOT ROLL, A TWO-HIGH REVERSING MILL THAT PRODUCES THE LONGEST COPPER AND ALLOY STRIP IN THE U.S. INDUSTRY. OVERALL LENGTH OF THE RUN-OUT LINE IS 300'. - American Brass Foundry, 70 Sayre Street, Buffalo, Erie County, NY

  13. Rolling, slip and traction measurements on low modulus materials

    NASA Technical Reports Server (NTRS)

    Tevaarwerk, J. L.

    1985-01-01

    Traction and wear tests were performed on six low modulus materials (LMM). Three different traction tests were performed to determine the suitability of the material for use as traction rollers. These were the rolling, slip and endurance traction tests. For each material the combination LMM on LMM and LMM on steel were evaluated. Rolling traction test were conducted to determine the load - velocity limits, the rolling traction coefficient of the materials and to establish the type of failures that would result when loading beyond the limit. It was found that in general a simple constant rolling traction coefficient was enough to describe the results of all the test. The slip traction tests revealed that the peak traction coefficients were considerably higher than for lubricated traction contacts. The endurance traction tests were performed to establish the durability of the LMM under conditions of prolonged traction. Wear measurements were performed during and after the test. Energetic wear rates were determined from the wear measurements conducted in the endurance traction tests. These values show that the roller wear is not severe when reasonable levels of traction are transmitted.

  14. Precession of a Spinning Ball Rolling down an Inclined Plane

    ERIC Educational Resources Information Center

    Cross, Rod

    2015-01-01

    A routine problem in an introductory physics course considers a rectangular block at rest on a plane inclined at angle a to the horizontal. In order for the block not to slide down the incline, the coefficient of sliding friction, µ, must be at least tan a. The situation is similar for the case of a ball rolling down an inclined plane. In order…

  15. 46 CFR 28.575 - Severe wind and roll.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... roll to windward, A1, is measured from the equilibrium angle, Ael, and is calculated by the following... metric units are used. (d) The angle of equilibrium, Ael in figure 28.575, is calculated by determining... equilibrium, Ael in figure 28.575, must not exceed 14° (0.24 radians). (g) Area “b” in figure 28.575 must...

  16. 46 CFR 28.575 - Severe wind and roll.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... roll to windward, A1, is measured from the equilibrium angle, Ael, and is calculated by the following... metric units are used. (d) The angle of equilibrium, Ael in figure 28.575, is calculated by determining... equilibrium, Ael in figure 28.575, must not exceed 14° (0.24 radians). (g) Area “b” in figure 28.575 must...

  17. 9. COMPLETED ROLLING CAMERA CAR ON RAILROAD TRACK AND BRIDGE ...

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

    9. COMPLETED ROLLING CAMERA CAR ON RAILROAD TRACK AND BRIDGE LOOKING WEST, APRIL 26, 1948. (ORIGINAL PHOTOGRAPH IN POSSESSION OF DAVE WILLIS, SAN DIEGO, CALIFORNIA.) - Variable Angle Launcher Complex, Camera Car & Track, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

  18. Foucault Dissipation in a Rolling Cylinder: A Webcam Quantitative Study

    ERIC Educational Resources Information Center

    Bonanno, A.; Bozzo, G.; Camarca, M.; Sapia, P.

    2011-01-01

    In this paper we present an experimental strategy to measure the micro power dissipation due to Foucault "eddy" currents in a copper cylinder rolling on two parallel conductive rails in the presence of a magnetic field. Foucault power dissipation is obtained from kinematical measurements carried out by using a common PC webcam and video analysis…

  19. Taylorwilson four roll straightener of the no. 1 seamless line ...

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

    Taylor-wilson four roll straightener of the no. 1 seamless line in bay 12 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  20. Looking south at the aetna standard piercer and mannesman rolls ...

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

    Looking south at the aetna standard piercer and mannesman rolls of the no. 2 seamless line in bay 19 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  1. Simulating Roll Clouds associated with Low-Level Convergence.

    NASA Astrophysics Data System (ADS)

    Prasad, A. A.; Sherwood, S. C.

    2015-12-01

    Convective initiation often takes place when features such as fronts and/or rolls collide, merge or otherwise meet. Rolls indicate boundary layer convergence and may initiate thunderstorms. These are often seen in satellite and radar imagery prior to the onset of deep convection. However, links between convergence driven rolls and convection are poor in global models. The poor representation of convection is the source of many model biases, especially over the Maritime Continent in the Tropics. We simulate low-level convergence lines over north-eastern Australia using the Weather Research and Forecasting (WRF) Model (version 3.7). The simulations are events from September-October 2002 driven by sea breeze circulations. Cloud lines associated with bore-waves that form along the low-level convergence lines are thoroughly investigated in this study with comparisons from satellite and surface observations. Initial simulations for a series of cloud lines observed on 4th October, 2002 over the Gulf of Carpentaria showed greater agreement in the timing and propagation of the disturbance and the low-level convergence, however the cloud lines or streets of roll clouds were not properly captured by the model. Results from a number of WRF simulations with different microphysics, cumulus and planetary boundary layer schemes, resolution and boundary conditions will also be discussed.

  2. Convergence reduces ocular counterroll (OCR) during static roll-tilt.

    PubMed

    Ooi, D; Cornell, E D; Curthoys, I S; Burgess, A M; MacDougall, H G

    2004-11-01

    When humans are roll-tilted around the naso-occipital axis, both eyes roll or tort in the opposite direction to roll-tilt, a phenomenon known as ocular counterroll (OCR). While the magnitude of OCR is primarily determined by vestibular, somatosensory, and proprioceptive input, direction of gaze also plays a major role. The aim of this study was to measure the interaction between some of these factors in the control of OCR. Videooculography was used to measure 3D eye position during maintained whole body (en bloc) static roll-tilt in darkness, while subjects fixated first on a distant (at 130 cm) and then a near (at 30 cm) head-fixed target aligned with the subject's midline. We found that while converging on the near target, human subjects displayed a significant reduction in OCR for both directions of roll-tilt--i.e. the interaction between OCR and vergence was not simple addition or subtraction of torsion induced by vergence with torsion induced by roll-tilt. To remove the possibility that the OCR reduction may be associated with the changed horizontal position of the eye in the orbit during symmetric convergence, we ran an experiment using asymmetric convergence in which the distant and near targets were aligned directly in front of one eye. We found the magnitude of OCR in this asymmetric convergence case was also reduced for near viewing by about the same amount as in the symmetric vergence condition, confirming that the convergence command rather than horizontal position of the eye underlies the OCR reduction, since there was no horizontal movement of the aligned eye in the orbit between fixation on the distant and near targets. Increasing vergence from 130 to 30 cm reduced OCR gain by around 35% on average. That reduction was equal in both eyes and occurred in both the symmetric and asymmetric convergence conditions. These results demonstrate the important role vergence plays in determining ocular counterroll during roll-tilt and may support the contention

  3. EFFECT OF DIFFERENT FOAM ROLLING VOLUMES ON KNEE EXTENSION FATIGUE

    PubMed Central

    Neto, Victor Gonçalves Corrêa

    2016-01-01

    Background Foam rolling (FR) is a common intervention utilized for the purpose of acutely increasing range-of-motion without subsequent decreases in performance. FR is characterized as an active technique which subject performs upon themselves. Thus, it is believed that the accumulated fatigue can influence whether the task can be continued. Purpose To analyze the effect of different foam rolling volumes on fatigue of the knee extensors. Methods Twenty-five recreationally active females (age 27.7 ± 3.56 y, height 168.4 ± 7.1 cm, weight 69.1 ± 10.2 kg) were recruited for the study. The experiment involved three sets of knee extensions with a pre-determined 10 repetition maximum load to concentric failure. Then, subjects performed the control (CONT) and foam rolling (FR) conditions. FR conditions consisted of different anterior thigh rolling volumes (60-, 90-, and 120-seconds) which were performed during the inter-set rest period. After that, the fatigue index was calculated and compared between each experimental condition. Fatigue index indicates how much (%) resistance the subjects experienced, calculated by the equation: (thidset/firstset) x 100. Results Fatigue index was statistically significantly greater (greater fatigue resistance) for CONT compared to FR90 (p = 0.001) and FR120 (p = 0.001). Similarly, higher fatigue resistance was observed for FR60 when compared to FR120 (p = 0.048). There were no significant differences between the other conditions (p > 0.005). Conclusion The finding of foam rolling fatigue index decline (less fatigue resistance) as compared to control conditions may have implications for foam rolling prescription and implementation, in both rehabilitation and athletic populations. For the purposes of maximum repetition performance, foam rolling should not be applied to the agonist muscle group between sets of knee extensions. Moreover, it seems that volumes greater than 90-seconds are detrimental to the

  4. Influence of relative rolling reduction and thickness layers bimetallic plate at the non-uniformity of the strain after rolling process

    NASA Astrophysics Data System (ADS)

    Rydz, D.; Stradomski, G.; Dyja, H.

    2017-02-01

    In the article were made numerical and laboratory tests of two-layers rolling process sheet composed of Al99,8 + M1E. Laboratory tests made with use of 150 mm diameter working rolls mill. To the modeling of the bimetallic plate rolling were taken the FEM Forge 2D software based on the theory of plasticity and MathCad program (in which to the rolling process modeling were used the mathematical model developed in the work [5] based on the theory of viscoelasticity). The aim of study was to determine the influence of layer thickness HT0/HM0 and relative deformation ε on the uneven distribution of steel sheet deformation after rolling process. Calculations based on the theory of viscoelasticity allowed additionally take into account the impact of the delayed effects of the variation of viscoelastic deformation of layers of the bimetallic plate rolling process.

  5. Design of roll-to-roll printing equipment with multiple printing methods for multi-layer printing.

    PubMed

    Kim, Chung Hwan; Jo, Jeongdai; Lee, Seung-Hyun

    2012-06-01

    In this paper, a novel design concept for roll-to-roll printing equipment used for manufacturing printed electronic devices by multi-layer printing is presented. The roll-to-roll printing system mainly consists of printing units for patterning the circuits, tension control components such as feeders, dancers, load cells, register measurement and control units, and the drying units. It has three printing units which allow switching among the gravure, gravure-offset, and flexo printing methods by changing the web path and the placements of the cylinders. Therefore, depending on the application devices and the corresponding inks used, each printing unit can be easily adjusted to the required printing method. The appropriate printing method can be chosen depending on the desired printing properties such as thickness, roughness, and printing quality. To provide an example of the application of the designed printing equipment, we present the results of printing tests showing the variations in the printing properties of the ink for different printing methods.

  6. Waveguide slot-excited long racetrack electron cyclotron resonance plasma source for roll-to-roll (scanning) processing.

    PubMed

    You, H-J

    2013-07-01

    We present a SLot-excited ANtenna (SLAN) long racetrack ECR plasma source that is utilized for roll-to-roll plasma processing such as thin film encapsulation of large-area OLED (organic light emitting diode) panel or modification of fabric surfaces. This source is designed to be long, and to operate under high density uniform plasma with sub-milli-torr pressures. The above features are accomplished by a slot-excited long racetrack resonator with a toroidal geometry of magnetic field ECR configuration, and reinforced microwave electric distributions along the central region of plasma chamber. Also, a new feature has been added to the source. This is to employ a tail plunger, which allows the microwave electric field and the uniformity of the plasma profile to be easily adjustable. We have successfully generated Ar plasmas operating with the microwave power of 0.5-3 kW in the pressure range of 0.2-10 mTorr. The plasma is uniform (<10%) in the direction of the straight track and has a Gaussian profile in the roll-to-roll (scanning) direction. In addition, it is shown that the tail plunger could adjust the plasma profile in order to obtain plasma uniformity. Furthermore, based on the results, we suggest a newly designed up-scaled racetrack-SLAN source.

  7. Large Scale Triboelectric Nanogenerator and Self-Powered Pressure Sensor Array Using Low Cost Roll-to-Roll UV Embossing

    PubMed Central

    Dhakar, Lokesh; Gudla, Sudeep; Shan, Xuechuan; Wang, Zhiping; Tay, Francis Eng Hock; Heng, Chun-Huat; Lee, Chengkuo

    2016-01-01

    Triboelectric nanogenerators (TENGs) have emerged as a potential solution for mechanical energy harvesting over conventional mechanisms such as piezoelectric and electromagnetic, due to easy fabrication, high efficiency and wider choice of materials. Traditional fabrication techniques used to realize TENGs involve plasma etching, soft lithography and nanoparticle deposition for higher performance. But lack of truly scalable fabrication processes still remains a critical challenge and bottleneck in the path of bringing TENGs to commercial production. In this paper, we demonstrate fabrication of large scale triboelectric nanogenerator (LS-TENG) using roll-to-roll ultraviolet embossing to pattern polyethylene terephthalate sheets. These LS-TENGs can be used to harvest energy from human motion and vehicle motion from embedded devices in floors and roads, respectively. LS-TENG generated a power density of 62.5 mW m−2. Using roll-to-roll processing technique, we also demonstrate a large scale triboelectric pressure sensor array with pressure detection sensitivity of 1.33 V kPa−1. The large scale pressure sensor array has applications in self-powered motion tracking, posture monitoring and electronic skin applications. This work demonstrates scalable fabrication of TENGs and self-powered pressure sensor arrays, which will lead to extremely low cost and bring them closer to commercial production. PMID:26905285

  8. Large Scale Triboelectric Nanogenerator and Self-Powered Pressure Sensor Array Using Low Cost Roll-to-Roll UV Embossing

    NASA Astrophysics Data System (ADS)

    Dhakar, Lokesh; Gudla, Sudeep; Shan, Xuechuan; Wang, Zhiping; Tay, Francis Eng Hock; Heng, Chun-Huat; Lee, Chengkuo

    2016-02-01

    Triboelectric nanogenerators (TENGs) have emerged as a potential solution for mechanical energy harvesting over conventional mechanisms such as piezoelectric and electromagnetic, due to easy fabrication, high efficiency and wider choice of materials. Traditional fabrication techniques used to realize TENGs involve plasma etching, soft lithography and nanoparticle deposition for higher performance. But lack of truly scalable fabrication processes still remains a critical challenge and bottleneck in the path of bringing TENGs to commercial production. In this paper, we demonstrate fabrication of large scale triboelectric nanogenerator (LS-TENG) using roll-to-roll ultraviolet embossing to pattern polyethylene terephthalate sheets. These LS-TENGs can be used to harvest energy from human motion and vehicle motion from embedded devices in floors and roads, respectively. LS-TENG generated a power density of 62.5 mW m‑2. Using roll-to-roll processing technique, we also demonstrate a large scale triboelectric pressure sensor array with pressure detection sensitivity of 1.33 V kPa‑1. The large scale pressure sensor array has applications in self-powered motion tracking, posture monitoring and electronic skin applications. This work demonstrates scalable fabrication of TENGs and self-powered pressure sensor arrays, which will lead to extremely low cost and bring them closer to commercial production.

  9. Large Scale Triboelectric Nanogenerator and Self-Powered Pressure Sensor Array Using Low Cost Roll-to-Roll UV Embossing.

    PubMed

    Dhakar, Lokesh; Gudla, Sudeep; Shan, Xuechuan; Wang, Zhiping; Tay, Francis Eng Hock; Heng, Chun-Huat; Lee, Chengkuo

    2016-02-24

    Triboelectric nanogenerators (TENGs) have emerged as a potential solution for mechanical energy harvesting over conventional mechanisms such as piezoelectric and electromagnetic, due to easy fabrication, high efficiency and wider choice of materials. Traditional fabrication techniques used to realize TENGs involve plasma etching, soft lithography and nanoparticle deposition for higher performance. But lack of truly scalable fabrication processes still remains a critical challenge and bottleneck in the path of bringing TENGs to commercial production. In this paper, we demonstrate fabrication of large scale triboelectric nanogenerator (LS-TENG) using roll-to-roll ultraviolet embossing to pattern polyethylene terephthalate sheets. These LS-TENGs can be used to harvest energy from human motion and vehicle motion from embedded devices in floors and roads, respectively. LS-TENG generated a power density of 62.5 mW m(-2). Using roll-to-roll processing technique, we also demonstrate a large scale triboelectric pressure sensor array with pressure detection sensitivity of 1.33 V kPa(-1). The large scale pressure sensor array has applications in self-powered motion tracking, posture monitoring and electronic skin applications. This work demonstrates scalable fabrication of TENGs and self-powered pressure sensor arrays, which will lead to extremely low cost and bring them closer to commercial production.

  10. Roll-to-roll DBD plasma pretreated polyethylene web for enhancement of Al coating adhesion and barrier property

    NASA Astrophysics Data System (ADS)

    Zhang, Haibao; Li, Hua; Fang, Ming; Wang, Zhengduo; Sang, Lijun; Yang, Lizhen; Chen, Qiang

    2016-12-01

    In this paper the roll-to-roll atmospheric dielectric barrier discharge (DBD) was used to pre-treat polyethylene (PE) web surface before the conventional thermal evaporation aluminum (Al) was performed as a barrier layer. We emphasized the plasma environment effect based on the inlet three kinds of reactive monomers. The cross hatch test was employed to assess the Al coating adhesion; and the oxygen transmission rate (OTR) was used to evaluate gas barrier property. The results showed that after roll-to-roll DBD plasma treatment all Al coatings adhered strongly on PE films and were free from pinhole defects with mirror morphology. The OTR was reduced from 2673 cm3/m2 day for Al-coated original PE to 138 cm3/m2 day for Al-coated allyamine (C3H7N) modified PE. To well understand the mechanism the chemical compositions of the untreated and DBD plasma pretreated PE films were analyzed by X-ray photoelectron spectroscopy (XPS). The surface topography was characterized by atomic force microscopy (AFM). For the property of surface energy the water contact angle measurement was also carried out in the DBD plasma treated samples with deionized water.

  11. Pechiney Rolled Products: Plant-Wide Energy Assessment Identifies Opportunities to Optimize Aluminum Casting and Rolling Operations

    SciTech Connect

    Not Available

    2004-07-01

    A Pechiney Rolled Products plant focused on various aluminum casting processes during a PWA. The assessment revealed potential annual savings of 460,000 MMBtu in natural gas, 9.6 million kWh in electricity, 69 million pounds in CO2, and $2.5 million.

  12. Large format cylindrical lens films formed by roll-to-roll ultraviolet embossing and applications as diffusion films

    NASA Astrophysics Data System (ADS)

    Shan, X. C.; Liu, T.; Mohaime, M.; Salam, B.; Liu, Y. C.

    2015-03-01

    A roll-to-roll (R2R) ultraviolet (UV) embossing system has been developed for manufacturing micro features on continuous flexible films. The R2R UV embossing system, which has an embossing roller of 160 mm in diameter, can handle flexible polymer films with a width up to 500 mm and thickness ranging from 0.05 to 0.5 mm. A metal sheet template with micro features on its surface is mounted to the embossing roller and used as embossing mould. A slot die coating unit that has a coating width of 250 mm is used to deposit liquid UV curable resin on polymer films and coating thickness ranging from 10 to 50 µm has been achieved. Continuous roll-to-roll UV embossing is conducted and optical films with cylindrical lens arrays (curvature radius = 112  ±  2 µm, sag height = 28  ±  0.5 µm and pitch = 150  ±  2 µm) are formed. The optical films are used for diffusion to improve light uniformity of a printed lighting film that consists of lighting stripes and dark blank lines. The evaluation results show that the non-uniformity of light intensity can be reduced from 30% (with only lighting panel) to about 3% with the cylindrical lens films.

  13. Direct and precise measurement of displacement and velocity of flexible web in roll-to-roll manufacturing systems.

    PubMed

    Kang, Dongwoo; Kim, Young duk; Lee, Eonseok; Choi, Young-Man; Lee, Taik-Min; Kim, Dongmin

    2013-12-01

    Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accurate as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm.

  14. Direct and precise measurement of displacement and velocity of flexible web in roll-to-roll manufacturing systems

    SciTech Connect

    Kang, Dongwoo; Lee, Eonseok; Choi, Young-Man; Lee, Taik-Min; Kim, Duk Young; Kim, Dongmin

    2013-12-15

    Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accurate as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm.

  15. The effect of mold materials on the overlay accuracy of a roll-to-roll imprinting system using UV LED illumination within a transparent mold

    NASA Astrophysics Data System (ADS)

    Choi, Sungwoo; Kook, YunHo; Kim, ChulHo; Yoo, SoonSung; Park, Kwon-Shik; Kim, Seok-min; Kang, Shinill

    2016-06-01

    Although several studies on the roll-to-roll (R2R) imprinting process have reported achieving flexible electronics, improving the alignment accuracy in the overlay process of R2R imprinting is recognized as the biggest problem for the commercialization of this technology. For an overlay technique with high alignment accuracy, it is essential to develop a roll mold with high positional accuracy. In this study, a method for fabricating a roll mold with high positional accuracy is proposed by wrapping a thin glass substrate flexible mold around the transparent roll base, because it can provide higher mechanical strength and thermal stability than a conventional polymer substrate. To confirm the usability of the proposed process, the prepared roll mold was used to fabricate a test pattern of thin-film transistor backplane for a rollable display. The positional and overlay accuracy of the roll mold with the proposed thin glass substrate flexible mold were compared with the roll mold with a conventional polymer substrate flexible mold. Large-area transparent flexible molds with a size of 470  ×  370 mm were fabricated by an ultraviolet (UV) imprinting process on thin glass and polyethylene terephthalate substrates, and these flexible molds were wrapped around a roll base of 125 mm radius through a precision alignment process. After an anti-adhesion treatment and the wrapping process, the roll mold with the polymer substrate showed a ~180 μm positional error, whereas the thin glass substrate showed a ~30 μm positional error. After the overlay process using the R2R imprinting system with the alignment system, an average overlay error of ~3 μm was obtained when the thin glass flexible wrapped roll mold was used, whereas a ~22 μm overlay error was obtained when the polymer substrate flexible wrapped roll mold was used.

  16. Roll-On/Roll-Off (RO/RO) Discharge Facility Tests with MV CYGNUS and SS ATLANTIC BEAR (COTS CNO Project 299, DT-IIF-1).

    DTIC Science & Technology

    1983-11-01

    AD-R139 346 ROLL-ON/ROLL-OFF (RO/RO) DISCHARGE FACILITY TESTS NITH 1/1 MY CYGNUS AND SS A..(U) DAVID N TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT...MICROCOPY RESOLUTION TEST CHART NATIONA. DUEAU OF STANOAD$S-1963-A •-’ ,jh DAVID W. TAYLOR NAVAL SHIP RMSEARCH AND DEVELOPMENT CENTER ROLL-ON/ROLL...by the David W. Taylor Naval Ship Research and Development Center (DTNSRDC), Mobile Support Systems Office, Code 1190, Task Area Y0816.002 and Work

  17. The role of compressional viscoelasticity in the lubrication of rolling contacts.

    NASA Technical Reports Server (NTRS)

    Harrison, G.; Trachman, E. G.

    1972-01-01

    A simple model for the time-dependent volume response of a liquid to an applied pressure step is used to calculate the variation with rolling speed of the traction coefficient in a rolling contact system. Good agreement with experimental results is obtained at rolling speeds above 50 in/sec. At lower rolling speeds a very rapid change in the effective viscosity of the lubricant is predicted. This behavior, in conjunction with shear rate effects, is shown to lead to large errors when experimental data are extrapolated to zero rolling speed.

  18. Rolled-up inductor structure for a radiofrequency integrated circuit (RFIC)

    SciTech Connect

    Li, Xiuling; Huang, Wen; Ferreira, Placid M.; Yu, Xin

    2015-12-29

    A rolled-up inductor structure for a radiofrequency integrated circuit (RFIC) comprises a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises a conductive pattern layer on a strain-relieved layer, and the conductive pattern layer comprises at least one conductive strip having a length extending in a rolling direction. The at least one conductive strip thereby wraps around the longitudinal axis in the rolled configuration. The conductive pattern layer may also comprise two conductive feed lines connected to the conductive strip for passage of electrical current therethrough. The conductive strip serves as an inductor cell of the rolled-up inductor structure.

  19. A method to design blended rolled edges for compact range reflectors

    NASA Technical Reports Server (NTRS)

    Gupta, Inder J.; Burnside, Walter D.

    1989-01-01

    A method to design blended rolled edges for arbitrary rim shape compact range reflectors is presented. The reflectors may be center-fed or offset-fed. The method leads to rolled edges with minimal surface discontinuities. It is shown that the reflectors designed using the prescribed method can be defined analytically using simple expressions. A procedure to obtain optimum rolled edges parameter is also presented. The procedure leads to blended rolled edges that minimize the diffracted fields emanating from the junction between the paraboloid and the rolled edge surface while satisfying certain constraints regarding the reflector size and the minimum operating frequency of the system.

  20. Human ocular counter-rolling and roll tilt perception during off-vertical axis rotation after spaceflight.

    PubMed

    Clément, Gilles; Denise, Pierre; Reschke, Millard F; Wood, Scott J

    2007-01-01

    Ocular counter-rolling (OCR) induced by whole body tilt in roll has been explored after spaceflight as an indicator of the adaptation of the otolith function to microgravity. It has been claimed that the overall pattern of OCR responses during static body tilt after spaceflight is indicative of a decreased role of the otolith function, but the results of these studies have not been consistent, mostly due to large variations in the OCR within and across individuals. By contrast with static head tilt, off-vertical axis rotation (OVAR) presents the advantage of generating a sinusoidal modulation of OCR, allowing averaged measurements over several cycles, thus improving measurement accuracy. Accordingly, OCR and the sense of roll tilt were evaluated in seven astronauts before and after spaceflight during OVAR at 45 degrees/s in darkness at two angles of tilt (10 degrees and 20 degrees). There was no significant difference in OCR during OVAR immediately after landing compared to preflight. However, the amplitude of the perceived roll tilt during OVAR was significantly larger immediately postflight, and then returned to control values in the following days. Since the OCR response is predominantly attributed to the shearing force exerted on the utricular macula, the absence of change in OCR postflight suggests that the peripheral otolith organs function normally after short-term spaceflight. However, the increased sense of roll tilt indicates an adaptation in the central processing of gravitational input, presumably related to a re-weighting of the internal representation of gravitational vertical as a result of adaptation to microgravity.

  1. Impact of vertical wind shear on roll structure in idealized hurricane boundary layers

    NASA Astrophysics Data System (ADS)

    Wang, Shouping; Jiang, Qingfang

    2017-03-01

    Quasi-two-dimensional roll vortices are frequently observed in hurricane boundary layers. It is believed that this highly coherent structure, likely caused by the inflection-point instability, plays an important role in organizing turbulent transport. Large-eddy simulations are conducted to investigate the impact of wind shear characteristics, such as the shear strength and inflection-point level, on the roll structure in terms of its spectral characteristics and turbulence organization. A mean wind nudging approach is used in the simulations to maintain the specified mean wind shear without directly affecting turbulent motions. Enhancing the radial wind shear expands the roll horizontal scale and strengthens the roll's kinetic energy. Increasing the inflection-point level tends to produce a narrow and sharp peak in the power spectrum at the wavelength consistent with the roll spacing indicated by the instantaneous turbulent fields. The spectral tangential momentum flux, in particular, reaches a strong peak value at the roll wavelength. In contrast, the spectral radial momentum flux obtains its maximum at the wavelength that is usually shorter than the roll's, suggesting that the roll radial momentum transport is less efficient than the tangential because of the quasi-two-dimensionality of the roll structure. The most robust rolls are produced in a simulation with the highest inflection-point level and relatively strong radial wind shear. Based on the spectral analysis, the roll-scale contribution to the turbulent momentum flux can reach 40 % in the middle of the boundary layer.

  2. Load-signature analysis for pack rolling of near-gamma titanium aluminide alloys

    SciTech Connect

    Semiatin, S.L. . Metals and Ceramics Division); Seetharaman, V. )

    1994-11-01

    The objective of the present work was to demonstrate the sensitivity of rolling-load signature analysis as a means to monitor hot-pack-rolling processes for the fabrication of sheet of near-gamma titanium-aluminide alloy sand other difficult-to-work materials. In previous work, a simple method was developed for the prediction of temperature transients during two steps in the pack-rolling process: the transfer of the pack from the furnace to the rolling mill and the actual rolling operation itself. The accuracy of the temperature-transient calculations was established through load-signature data obtained during trials for Ti-48Al (atomic percent) rolled at a single nominal (furnace) temperature. In the present work, additional results are presented and discussed for hot pack rolling at various nominal temperatures and for a range of near-gamma titanium-aluminide alloys.

  3. A study of roll attractor and wing rock of delta wings at high angles of attack

    NASA Technical Reports Server (NTRS)

    Niranjana, T.; Rao, D. M.; Pamadi, Bandu N.

    1993-01-01

    Wing rock is a high angle of attack dynamic phenomenon of limited cycle motion predominantly in roll. The wing rock is one of the limitations to combat effectiveness of the fighter aircraft. Roll Attractor is the steady state or equilibrium trim angle (phi(sub trim)) attained by the free-to-roll model, held at some angle of attack, and released form rest at a given initial roll (bank) angle (phi(sub O)). Multiple roll attractors are attained at different trim angles depending on initial roll angle. The test facility (Vigyan's low speed wind tunnel) and experimental work is presented here along with mathematical modelling of roll attractor phenomenon and analysis and comparison of predictions with experimental data.

  4. Lattice Boltzmann Simulation of Blood Flow in Blood Vessels with the Rolling Massage

    NASA Astrophysics Data System (ADS)

    Yi, Hou-Hui; Xu, Shi-Xiong; Qian, Yue-Hong; Fang, Hai-Ping

    2005-12-01

    The rolling massage manipulation is a classic Chinese massage, which is expected to improve the circulation by pushing, pulling and kneading of the muscle. A model for the rolling massage manipulation is proposed and the lattice Boltzmann method is applied to study the blood flow in the blood vessels. The simulation results show that the blood flux is considerably modified by the rolling massage and the explicit value depends on the rolling frequency, the rolling depth, and the diameter of the vessel. The smaller the diameter of the blood vessel, the larger the enhancement of the blood flux by the rolling massage. The model, together with the simulation results, is expected to be helpful to understand the mechanism and further development of rolling massage techniques.

  5. Rolling-Tooth Core Breakoff and Retention Mechanism

    NASA Technical Reports Server (NTRS)

    Badescu, Mircea; Bickler, Donald B.; Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi; Hudson, Nicolas H.

    2011-01-01

    Sampling cores requires the controlled breakoff of the core at a known location with respect to the drill end. An additional problem is designing a mechanism that can be implemented at a small scale that is robust and versatile enough to be used for a variety of core samples. This design consists of a set of tubes (a drill tube and an inner tube) and a rolling element (rolling tooth). An additional tube can be used as a sample tube. The drill tube and the inner tube have longitudinal holes with the axes offset from the axis of each tube. The two eccentricities are equal. The inner tube fits inside the drill tube, and the sample tube fits inside the inner tube. While drilling, the two tubes are positioned relative to each other such that the sample tube is aligned with the drill tube axis and core. The drill tube includes teeth and flutes for cuttings removal. The inner tube includes, at the base, the rolling element implemented as a wheel on a shaft in an eccentric slot. An additional slot in the inner tube and a pin in the drill tube limit the relative motion of the two tubes. While drilling, the drill assembly rotates relative to the core and forces the rolling tooth to stay hidden in the slot along the inner tube wall. When the drilling depth has been reached, the drill bit assembly is rotated in the opposite direction, and the rolling tooth is engaged and penetrates into the core. Depending on the strength of the created core, the rolling tooth can score, lock the inner tube relative to the core, start the eccentric motion of the inner tube, and break the core. The tooth and the relative position of the two tubes can act as a core catcher or core-retention mechanism as well. The design was made to fit the core and hole parameters produced by an existing bit; the parts were fabricated and a series of demonstration tests were performed. This invention is potentially applicable to sample return and in situ missions to planets such as Mars and Venus, to moons such

  6. Analysis of Roll Steering for Solar Electric Propulsion Missions

    NASA Technical Reports Server (NTRS)

    Pederson, Dylan, M.; Hojnicki, Jeffrey, S.

    2012-01-01

    Nothing is more vital to a spacecraft than power. Solar Electric Propulsion (SEP) uses that power to provide a safe, reliable, and, most importantly, fuel efficient means to propel a spacecraft to its destination. The power performance of an SEP vehicle s solar arrays and electrical power system (EPS) is largely influenced by the environment in which the spacecraft is operating. One of the most important factors that determines solar array power performance is how directly the arrays are pointed to the sun. To get the most power from the solar arrays, the obvious solution is to point them directly at the sun at all times. Doing so is not a problem in deep space, as the environment and pointing conditions that a spacecraft faces are fairly constant and are easy to accommodate, if necessary. However, large and sometimes rapid variations in environmental and pointing conditions are experienced by Earth orbiting spacecraft. SEP spacecraft also have the additional constraint of needing to keep the thrust vector aligned with the velocity vector. Thus, it is important to analyze solar array power performance for any vehicle that spends an extended amount of time orbiting the Earth, and to determine how much off-pointing can be tolerated to produce the required power for a given spacecraft. This paper documents the benefits and drawbacks of perfectly pointing the solar arrays of an SEP spacecraft spiraling from Earth orbit, and how this might be accomplished. Benefits and drawbacks are defined in terms of vehicle mass, power, volume, complexity, and cost. This paper will also look at the application of various solar array pointing methods to future missions. One such pointing method of interest is called roll steering . Roll steering involves rolling the entire vehicle twice each orbit. Roll steering, combined with solar array gimbal tracking, is used to point the solar arrays perfectly towards the sun at all points in the orbit, while keeping the vehicle thrusters aligned

  7. 76 FR 62039 - Certain Hot-Rolled Carbon Steel Flat Products From India: Final Results of 2009-2010 Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-06

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From India: Final Results of... certain hot-rolled carbon steel flat products from India (``hot-rolled steel'') manufactured by Ispat... Preliminary Results \\2\\ of this review. \\2\\ See Certain Hot-Rolled Carbon Steel Flat Products From...

  8. 76 FR 7546 - Certain Hot-Rolled Carbon Steel Flat Products From Brazil: Rescission of Countervailing Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-10

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From Brazil: Rescission of... review of the countervailing duty order on certain hot- rolled carbon steel flat products (hot-rolled... published in the Federal Register the countervailing duty order on hot-rolled steel from Brazil....

  9. 75 FR 27297 - Certain Hot-Rolled Carbon Steel Flat Products from India: Notice of Final Results of Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-14

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products from India: Notice of Final... antidumping duty administrative review for certain hot-rolled carbon steel flat products from India (``Indian Hot-Rolled''). See Certain Hot-Rolled Carbon Steel Flat Products from India: Notice of...

  10. 76 FR 66901 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Final...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-28

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of... duty order on certain hot-rolled carbon steel flat products (``hot-rolled'') from the People's Republic... Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Preliminary Intent...

  11. 78 FR 40428 - Certain Hot-Rolled Carbon Steel Flat Products from India: Rescission of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-05

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products from India: Rescission of... administrative review of the antidumping duty order on certain hot- rolled carbon steel flat products (hot rolled... January 30, 2013, the Department initiated an administrative review of hot rolled steel from...

  12. Effect of intermediate annealing on the microstructure and mechanical property of ZK60 magnesium alloy produced by twin roll casting and hot rolling

    SciTech Connect

    Chen, Hongmei; Zang, Qianhao; Yu, Hui; Zhang, Jing; Jin, Yunxue

    2015-08-15

    Twin roll cast (designated as TRC in short) ZK60 magnesium alloy strip with 3.5 mm thickness was used in this paper. The TRC ZK60 strip was multi-pass rolled at different temperatures, intermediate annealing heat treatment was performed when the thickness of the strip changed from 3.5 mm to 1 mm, and then continued to be rolled until the thickness reached to 0.5 mm. The effect of intermediate annealing during rolling process on microstructure, texture and room temperature mechanical properties of TRC ZK60 strip was studied by using OM, TEM, XRD and electronic universal testing machine. The introduction of intermediate annealing can contribute to recrystallization in the ZK60 sheet which was greatly deformed, and help to reduce the stress concentration generated in the rolling process. Microstructure uniformity and mechanical properties of the ZK60 alloy sheet were also improved; in particular, the room temperature elongation was greatly improved. When the TRC ZK60 strip was rolled at 300 °C and 350 °C, the room temperature elongation of the rolled sheet with 0.5 mm thickness which was intermediate annealed during the rolling process was increased by 95% and 72% than that of no intermediate annealing, respectively. - Highlights: • Intermediate annealing was introduced during hot rolling process of twin roll cast ZK60 alloy. • Intermediate annealing can contribute to recrystallization and reduce the stress concentration in the deformed ZK60 sheet. • Microstructure uniformity and mechanical properties of the ZK60 sheet were improved, in particular, the room temperature elongation. • The elongation of the rolled ZK60 sheet after intermediate annealed was increased by 95% and 72% than that of no intermediate annealing.

  13. Influence of different kinds of rolling on the crystallographic texture and magnetic induction of a NOG 3 wt% Si steel

    NASA Astrophysics Data System (ADS)

    Silva, J. M.; Baêta Júnior, E. S.; Moraes, N. R. D. C.; Botelho, R. A.; Felix, R. A. C.; Brandao, L.

    2017-01-01

    The purpose of this work was to study the influence of different kinds of rolling on the magnetic properties of NOG steel, an electric steel widely used in electrical motors. These properties are highly correlated with the crystallographic texture of the material, which can be changed by rolling. Three kinds of rolling were examined: conventional rolling, cross-rolling and asymmetrical rolling. The crystallographic texture was determined by X-ray diffraction and the magnetic properties were calculated from a theoretical model that related the magnetic induction to crystallographic texture through the anisotropy energy. The results show that cross-rolling yields higher values of magnetic induction than the other processes.

  14. Generalized slow roll approximation for large power spectrum features

    SciTech Connect

    Dvorkin, Cora; Hu, Wayne

    2010-01-15

    We develop a variant of the generalized slow roll approach for calculating the curvature power spectrum that is well suited for order unity deviations in power caused by sharp features in the inflaton potential. As an example, we show that predictions for a step function potential, which has been proposed to explain order unity glitches in the cosmic microwave background temperature power spectrum at multipoles l=20-40, are accurate at the percent level. Our analysis shows that to good approximation there is a single source function that is responsible for observable features and that this function is simply related to the local slope and curvature of the inflaton potential. These properties should make the generalized slow roll approximation useful for inflation-model-independent studies of features, both large and small, in the observable power spectra.

  15. Highly Thermally Stable Microstructure in Mg Fabricated Via Powder Rolling

    NASA Astrophysics Data System (ADS)

    Shen, J.; Imai, H.; Chen, B.; Ye, X.; Umeda, J.; Kondoh, K.

    2016-11-01

    The purpose of this article is to demonstrate a fascinating microstructure that ensures Mg has a high thermal stability. This is achieved by fabricating the Mg sample via powder rolling followed by powder metallurgy method. It is found that after Mg powders are pretreated for 15 rolling passes at room temperature and then consolidated by using spark plasma sintering, the Mg specimen exhibits a much finer grain structure. Such a grain structure then shows a super high thermal stability. Worthy of note is that many fractions of tensile twins were presented in the Mg specimen and survived a heat treatment at 500°C. After the heat treatment, the microhardness of the sample remained almost unchanged. The finding then gives rise to the possibility of using Mg as structural material at elevated temperatures.

  16. Production roll out plan for HANDI 2000 business management system

    SciTech Connect

    Adams, D.E.

    1998-09-29

    The Hanford Data Integration 2000 (HANDI 2000) Project will result in an integrated and comprehensive set of functional applications containing core information necessary to support the Project Hanford Management Contract (PHMC). It is based on the Commercial-Off-The-Shelf (COTS) product solution with commercially proven business processes. The COTS product solution set, of Passport (PP) and PeopleSoft (PS) software, supports finance, supply, human resources, and payroll activities under the current PHMC direction. The PP software is an integrated application for Accounts Payable, Contract Management, Inventory Management, Purchasing and Material Safety Data Sheets (MSDS). The PS software is an integrated application for Projects, General Ledger, Human Resources Training, Payroll, and Base Benefits. This set of software constitutes the Business Management System (BMS) and MSDS, a subset of the HANDI 2000 suite of systems. The primary objective of the Production Roll Out Plan is to communicate the methods and schedules for implementation and roll out to end users of BMS.

  17. Rolled lawn as tool for industrial barren remediation

    NASA Astrophysics Data System (ADS)

    Gorbacheva, T. T.; Ivanova, L. A.; Kikuchi, R.; Gerardo, R.

    2009-04-01

    Fast development of the industrial and urban territories during last century has led to great disturbance of natural ecosystems in a lot of regions of the world. In the Far North the risk resulted from technogenic influence involves essentially more expressed negative consequences for the nature comparing to a regions of averages and southern latitudes due to higher sensitivity of northern ecosystems. Since thirtieth years of last century industrial complexes on extraction and processing of nonferrous metals ores are functioned on Kola peninsula territory. They are powerful sources of emissions of acidifying substances and heavy metals. Long term influence of these emissions resulted in deep degradation of terrestrial ecosystems up to industrial barren arising in immediate proximity to industrial centre Monchegorsk. The most radical way of disturbed territories rehabilitation is biological remediation. In 2006-2008 innovative methods of high-quality grass cover performance was developed in local enterprise «VIPON» in Apatity. Vermiculite trademark «VIPON» is characterized by not broken structure of minerals combined with week reactance, high mechanical durability, favorable рН equal 6.5-7.0, valuable absorptive and ion exchange properties. Final product of proposed technology was rolled lawn which successfully applied for remediation of disturbed sites in urban territories as such as industrial plots with low contamination. One of abstract authors namely L.Ivanova is one of technology implementators. During 2008 the field test was performed near the smelter complex (67°51'N, 32°48'E) to estimate suitability of proposed method for site remediation in more severe conditions such as in industrial barren. The method is based on cultivation of perennial grasses using hydroponics with thermally inflated vermiculite from local deposit (Kovdor) followed by rolled lawn placement on very contaminated sites near Monchegorsk. Great advantage of rolled lawn is short

  18. The rolling texture of 18% Ni-350 maraging steel

    SciTech Connect

    Haq, A. ul; Khan, A.Q. )

    1993-02-01

    Texture development in hot rolled sheet and hot forged tube of 18% Ni-350 maraging steel has been studied after various degrees of cold deformation and flow turning, respectively. Hot rolled sheet exhibited considerable mechanical anisotropy. Weak texture development was observed following flow turning compared to cold deformation. Above 80% deformation, an increase in work hardening was accompanied by an increase in the orientation density of the texture component (001)[110]. Deformation of 97% leads to the development of the texture component (111)[110], with the highest orientation density 10.3 times random and a constant orientation density of 9 times random along [var phi][sub 1] at [phi] = 55[degree] and [var phi][sub 2] = 45[degree]. This texture was correlated with the appearance of shear bands in the microstructure.

  19. Scale-dependent gravitational waves from a rolling axion

    SciTech Connect

    Namba, Ryo; Shiraishi, Maresuke; Peloso, Marco; Unal, Caner; Sorbo, Lorenzo E-mail: peloso@physics.umn.edu E-mail: sorbo@physics.umass.edu

    2016-01-01

    We consider a model in which a pseudo-scalar field σ rolls for some e-folds during inflation, sourcing one helicity of a gauge field. These fields are only gravitationally coupled to the inflaton, and therefore produce scalar and tensor primordial perturbations only through gravitational interactions. These sourced signals are localized on modes that exit the horizon while the roll of σ is significant. We focus our study on cases in which the model can simultaneously produce (i) a large gravitational wave signal, resulting in observable B-modes of the CMB polarizations, and (ii) sufficiently small scalar perturbations, so to be in agreement with the current limits from temperature anisotropies. Different choices of parameters can instead lead to a localized and visible departure from gaussianity in the scalar sector, either at CMB or LSS scales.

  20. Hot-rolling nanowire transparent electrodes for surface roughness minimization.

    PubMed

    Hosseinzadeh Khaligh, Hadi; Goldthorpe, Irene A

    2014-01-01

    Silver nanowire transparent electrodes are a promising alternative to transparent conductive oxides. However, their surface roughness presents a problem for their integration into devices with thin layers such as organic electronic devices. In this paper, hot rollers are used to soften plastic substrates with heat and mechanically press the nanowires into the substrate surface. By doing so, the root-mean-square surface roughness is reduced to 7 nm and the maximum peak-to-valley value is 30 nm, making the electrodes suitable for typical organic devices. This simple process requires no additional materials, which results in a higher transparency, and is compatible with roll-to-roll fabrication processes. In addition, the adhesion of the nanowires to the substrate significantly increases.

  1. The rolling motion of an eccentrically loaded wheel

    NASA Astrophysics Data System (ADS)

    Theron, W. F. D.

    2000-09-01

    This article discusses the rolling motion on a rough plane of a wheel whose center of mass does not coincide with the axis; for example, when a heavy particle is fixed to the rim of a rigid hoop. In cases with large eccentricity, the resulting motion is surprisingly complex, with four phases being identified, namely rolling (without slipping), spinning, skidding, and "hopping," by which is meant that the wheel actually leaves the plane. The main result of this analysis is the identification of the conditions that are required for hopping to occur. A second result is that faster than gravity accelerations occur when the mass of the particle is greater than the mass of the hoop. Massless hoops are briefly discussed as a special case of the general results.

  2. Rolling friction and energy dissipation in a spinning disc

    PubMed Central

    Ma, Daolin; Liu, Caishan; Zhao, Zhen; Zhang, Hongjian

    2014-01-01

    This paper presents the results of both experimental and theoretical investigations for the dynamics of a steel disc spinning on a horizontal rough surface. With a pair of high-speed cameras, a stereoscopic vision method is adopted to perform omnidirectional measurements for the temporal evolution of the disc's motion. The experiment data allow us to detail the dynamics of the disc, and consequently to quantify its energy. From our experimental observations, it is confirmed that rolling friction is a primary factor responsible for the dissipation of the energy. Furthermore, a mathematical model, in which the rolling friction is characterized by a resistance torque proportional to the square of precession rate, is also proposed. By employing the model, we perform qualitative analysis and numerical simulations. Both of them provide results that precisely agree with our experimental findings. PMID:25197246

  3. Analytic study of a rolling sphere on a rough surface

    NASA Astrophysics Data System (ADS)

    Florea, Olivia A.; Rosca, Ileana C.

    2016-11-01

    In this paper it is realized an analytic study of the rolling's sphere on a rough horizontal plane under the action of its own gravity. The necessities of integration of the system of dynamical equations of motion lead us to find a reference system where the motion equations should be transformed into simpler expressions and which, in the presence of some significant hypothesis to permit the application of some original methods of analytical integration. In technical applications, the bodies may have a free rolling motion or a motion constrained by geometrical relations in assemblies of parts and machine parts. This study involves a lot of investigations in the field of tribology and of applied dynamics accompanied by experiments. Multiple recordings of several trajectories of the sphere, as well as their treatment of images, also followed by statistical processing experimental data allowed highlighting a very good agreement between the theoretical findings and experimental results.

  4. Rolling Circle Amplification of Complete Nematode Mitochondrial Genomes

    PubMed Central

    Tang, Sha; Hyman, Bradley C.

    2005-01-01

    To enable investigation of nematode mitochondrial DNA evolution, methodology has been developed to amplify intact nematode mitochondrial genomes in preparative yields using a rolling circle replication strategy. Successful reactions were generated from whole cell template DNA prepared by alkaline lysis of the rhabditid nematode Caenorhabditis elegans and a mermithid nematode, Thaumamermis cosgrovei. These taxa, representing the two major nematode classes Chromodorea and Enoplea, maintain mitochondrial genomes of 13.8 kb and 20.0 kb, respectively. Efficient amplifications were conducted on template DNA isolated from individual or pooled nematodes that were alive or stored at -80°C. Unexpectedly, these experiments revealed that multiple T. cosgrovei mitochondrial DNA haplotypes are maintained in our local population. Rolling circle amplification products can be used as templates for standard PCR reactions with specific primers that target mitochondrial genes or for direct DNA sequencing. PMID:19262866

  5. Large non-gaussianity in slow-roll inflation

    NASA Astrophysics Data System (ADS)

    Pirtskhalava, David; Santoni, Luca; Trincherini, Enrico; Vernizzi, Filippo

    2016-04-01

    Canonical models of single-field, slow-roll inflation do not lead to appreciable non-Gaussianity, unless derivative interactions of the inflaton become uncontrollably large. We propose a novel slow-roll scenario where scalar perturbations propagate at a subluminal speed, leading to sizeable equilateral non-Gaussianity, f NL equil ∝ 1/ c s 4 , largely insensitive to the ultraviolet physics. The model is based on a low-energy effective theory characterized by weakly broken invariance under internal galileon transformations, ϕ → ϕ + b μ x μ , which protects the properties of perturbations from large quantum corrections. This provides the unique alternative to models such as DBI inflation in generating strongly subluminal/non-Gaussian scalar perturbations.

  6. Recycle of valuable products from oily cold rolling mill sludge

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Zhang, Shen-gen; Tian, Jian-jun; Pan, De-an; Liu, Yang; Volinsky, Alex A.

    2013-10-01

    Oily cold rolling mill (CRM) sludge contains lots of iron and alloying elements along with plenty of hazardous organic components, which makes it as an attractive secondary source and an environmental contaminant at the same time. The compound methods of "vacuum distillation + oxidizing roasting" and "vacuum distillation + hydrogen reduction" were employed for the recycle of oily cold rolling mill sludge. First, the sludge was dynamically vacuum distilled in a rotating furnace at 50 r/min and 600°C for 3 h, which removed almost hazardous organic components, obtaining 89.2wt% ferrous resultant. Then, high purity ferric oxide powders (99.2wt%) and reduced iron powders (98.9wt%) were obtained when the distillation residues were oxidized and reduced, respectively. The distillation oil can be used for fuel or chemical feedstock, and the distillation gases can be collected and reused as a fuel.

  7. Experimental and computational evaluation of rolling bearing steel durability

    NASA Astrophysics Data System (ADS)

    Nohál, L.; Vaculka, M.

    2017-02-01

    Rolling element bearings are widely-used machine components and their failure can result in damage to the whole machine. A bearing failure can be caused by many factors. In most cases it is damage on the raceway surface as a result of rolling contact fatigue (RCF). This article describes the fatigue analysis consists of determining service-life of a roller bearing using a stress-strain analysis with finite element method and subsequent numeric calculation using software fe-safe with application of multiaxial fatigue criterion. These theoretical results are compared to the experiments carried out on AXMAT test-rig with more accurate defect detection using acoustic emission method. Numerical service-life calculation can be applied as tool for fatigue life prediction of full scale bearing with sufficient correlation with experimental results.

  8. Hot Rolling of Gamma Titanium Aluminide Foil (PREPRINT)

    DTIC Science & Technology

    2010-04-01

    the flow stress as a function of strain rate , the strength coefficient for the specific phase i, 10 and the strain - rate sensitivity (assumed to...extended to the case of rate - sensitive , incompressible materials by Suquet [14]. Subsequently, it was applied to conventional titanium alloys by...AFRL-RX-WP-TP-2010-4138 HOT ROLLING OF GAMMA TITANIUM ALUMINIDE FOIL (PREPRINT) S.L. Semiatin Metals Branch Metals, Ceramics & NDE

  9. Viscous and nonviscous models of the partially filled rolling can

    NASA Astrophysics Data System (ADS)

    Jackson, K. A.; Finck, J. E.; Bednarski, C. R.; Clifford, L. R.

    1996-03-01

    We examine the motion of soft drink cans rolling down an incline as a function of the amount of water in the can. Our observations show this behavior to be remarkably complex. We introduce models suggested by the experimental results which describe the limiting cases of a nonviscous fluid and an infinitely viscous fluid, and compare the results of the model calculations to our observations.

  10. Prediction of Ship Roll Damping. A State of the Art

    DTIC Science & Technology

    1981-09-01

    oscillation. The drag of the bilge keel can be expressed by the following formula, which was obtained by Ikeda et al. [ 351 (including the case of an...bilge keel (m) XBKI ; SS number of aft end of bilie keel XBK2 ; SS number of fore end of bilge keel 7) OGD,T,THETA 3F10.0 CGD ; =OG/d T ; roll period

  11. The effects of myofascial release with foam rolling on performance.

    PubMed

    Healey, Kellie C; Hatfield, Disa L; Blanpied, Peter; Dorfman, Leah R; Riebe, Deborah

    2014-01-01

    In the last decade, self-myofascial release has become an increasingly common modality to supplement traditional methods of massage, so a masseuse is not necessary. However, there are limited clinical data demonstrating the efficacy or mechanism of this treatment on athletic performance. The purpose of this study was to determine whether the use of myofascial rollers before athletic tests can enhance performance. Twenty-six (13 men and 13 women) healthy college-aged individuals (21.56 ± 2.04 years, 23.97 ± 3.98 body mass index, 20.57 ± 12.21 percent body fat) were recruited. The study design was a randomized crossover design in which subject performed a series of planking exercises or foam rolling exercises and then performed a series of athletic performance tests (vertical jump height and power, isometric force, and agility). Fatigue, soreness, and exertion were also measured. A 2 × 2 (trial × gender) analysis of variance with repeated measures and appropriate post hoc was used to analyze the data. There were no significant differences between foam rolling and planking for all 4 of the athletic tests. However, there was a significant difference between genders on all the athletic tests (p ≤ 0.001). As expected, there were significant increases from pre to post exercise during both trials for fatigue, soreness, and exertion (p ≤ 0.01). Postexercise fatigue after foam rolling was significantly less than after the subjects performed planking (p ≤ 0.05). The reduced feeling of fatigue may allow participants to extend acute workout time and volume, which can lead to chronic performance enhancements. However, foam rolling had no effect on performance.

  12. Aileron roll hysteresis effects on entry of space shuttle orbiter

    NASA Technical Reports Server (NTRS)

    Powell, R. W.

    1977-01-01

    Six-degree-of-freedom simulations of the space shuttle orbiter entry with control hysteresis were conducted on the NASA Langley Research Center interactive simulator known as the automatic reentry flight dynamics simulator. These simulations revealed that the vehicle can tolerate control hysteresis producing a + or - 50 percent change in the nominal aileron roll characteristics and an offset in the nominal characteristics equivalent to a + or - 5 deg aileron deflection with little increase in the reaction control system's fuel consumption.

  13. Human perceptual overestimation of whole body roll tilt in hypergravity

    PubMed Central

    Newman, Michael C.; Oman, Charles M.; Merfeld, Daniel M.; Young, Laurence R.

    2014-01-01

    Hypergravity provides a unique environment to study human perception of orientation. We utilized a long-radius centrifuge to study perception of both static and dynamic whole body roll tilt in hypergravity, across a range of angles, frequencies, and net gravito-inertial levels (referred to as G levels). While studies of static tilt perception in hypergravity have been published, this is the first to measure dynamic tilt perception (i.e., with time-varying canal stimulation) in hypergravity using a continuous matching task. In complete darkness, subjects reported their orientation perception using a haptic task, whereby they attempted to align a hand-held bar with their perceived horizontal. Static roll tilt was overestimated in hypergravity, with more overestimation at larger angles and higher G levels, across the conditions tested (overestimated by ∼35% per additional G level, P < 0.001). As our primary contribution, we show that dynamic roll tilt was also consistently overestimated in hypergravity (P < 0.001) at all angles and frequencies tested, again with more overestimation at higher G levels. The overestimation was similar to that for static tilts at low angular velocities but decreased at higher angular velocities (P = 0.006), consistent with semicircular canal sensory integration. To match our findings, we propose a modification to a previous Observer-type canal-otolith interaction model. Specifically, our data were better modeled by including the hypothesis that the central nervous system treats otolith stimulation in the utricular plane differently than stimulation out of the utricular plane. This modified model was able to simulate quantitatively both the static and the dynamic roll tilt overestimation in hypergravity measured experimentally. PMID:25540216

  14. Light airplane crash tests at three roll angles

    NASA Technical Reports Server (NTRS)

    Castle, C. B.; Alfaro-Bou, E.

    1979-01-01

    Three similar twin engine general aviation airplanes were crash tested at the Langley impact dynamics research facility at 27 m/sec and at nominal roll angles of 0 deg, -15 deg, and -30 deg. Other flight parameters were held constant. The test facility, instrumentation, test specimens, and test method are briefly described. Structural damage and accelerometer data for each of the three impact conditions are presented and discussed.

  15. Measurement of rolling friction by a damped oscillator

    NASA Technical Reports Server (NTRS)

    Dayan, M.; Buckley, D. H.

    1983-01-01

    An experimental method for measuring rolling friction is proposed. The method is mechanically simple. It is based on an oscillator in a uniform magnetic field and does not involve any mechanical forces except for the measured friction. The measured pickup voltage is Fourier analyzed and yields the friction spectral response. The proposed experiment is not tailored for a particular case. Instead, various modes of operation, suitable to different experimental conditions, are discussed.

  16. Support Assembly for Composite Laminate Materials During Roll Press Processing

    NASA Technical Reports Server (NTRS)

    Catella, Luke A.

    2011-01-01

    A composite laminate material is supported during the roll press processing thereof by an assembly having: first and second perforated films disposed adjacent to first and second opposing surfaces of a mixture of uncured resin and fibers defining the composite laminate material, a gas permeable encasement surrounding the mixture and the first and second films, a gas impervious envelope sealed about the gas permeable encasement, and first and second rigid plates clamped about the gas impervious envelope.

  17. Cold pressure welding by incremental rolling: Deformation zone analysis

    NASA Astrophysics Data System (ADS)

    Schmidt, Hans Christian; Homberg, Werner; Hoppe, Christian; Grundmeier, Guido; Hordych, Illia; Maier, Hans Jürgen

    2016-10-01

    In this paper we analyse the deformation zone that forms during cold welding of metal pairs by incremental rolling. The tool geometry has great influence on the forming behaviour and the overall shape of the metal part. In order to improve the process, an increase in surface exposure is aspired since it should lead to an increased weld strength. Six tool geometries were tested by means of FEA and analysed based on the surface exposure created between the surfaces in contact.

  18. Rolling circle amplification detection of RNA and DNA

    DOEpatents

    Christian, Allen T.; Pattee, Melissa S.; Attix, Cristina M.; Tucker, James D.

    2004-08-31

    Rolling circle amplification (RCA) has been useful for detecting point mutations in isolated nucleic acids, but its application in cytological preparations has been problematic. By pretreating cells with a combination of restriction enzymes and exonucleases, we demonstrate RCA in solution and in situ to detect gene copy number and single base mutations. It can also detect and quantify transcribed RNA in individual cells, making it a versatile tool for cell-based assays.

  19. Control of mechanical systems with rolling contacts: Applications to robotics

    NASA Astrophysics Data System (ADS)

    Sarkar, Nilanjan

    1993-01-01

    The problems of modeling and control of mechanical dynamic systems subject to rolling contacts are investigated. There are two important theoretical contributions in this dissertation. First, contact kinematic relationships up to second order are developed for two rigid bodies in point contact. These equations relate gross rigid body motion to the changes in the positions of the points of contact. Second, a unified approach to the control of mechanical systems subject to both holonomic and nonholonomic constraints is proposed. The basic approach is to extend the state-space to include, in the addition to the generalized coordinates and velocities, contact coordinates which describe the displacements of the contact points and their derivatives. This redundant state-space formulation provides a convenient way to specify output equations to control contact motion. The control problem is formulated as an affine nonlinear problem and a differential-geometric, control-theoretic approach is used to decouple and linearize such systems. It is shown that such a system, even though not input-state linearizable, is input-output linearizable. Further, the zero dynamics of such a system is shown to be Lagrange stable. The proposed methodology is applied to three different robotic systems: (1) wheeled mobile robots; (2) two arms manipulating an object with rolling contact between each arm and the object; and (3) a single robot arm maintaining controlled contact against a moving environment. In each case, a nonlinear controller is designed to achieve the desired performances. For mobile robots, a new control algorithm called dynamic path following is proposed and shown to be quite effective and robust. In the context of two arm manipulation, grasp adaptation through the control of contact motion is demonstrated. Maintaining rolling contact with a moving surface is formulated as an acatastatic system. The proposed scheme involves simultaneously controlling interaction forces as

  20. High speed cylindrical rolling element bearing analysis 'CYBEAN' - Analytic formulation

    NASA Technical Reports Server (NTRS)

    Kleckner, R. J.; Pirvics, J.; Castelli, V.

    1979-01-01

    This paper documents the analytic foundation and software architecture for the computerized mathematical simulation of high speed cylindrical rolling element bearing behavior. The software, CYBEAN (CYlindrical BEaring ANalysis), considers a flexible, variable geometry outer ring, EHD films, roller centrifugal and quasidynamic loads, roller tilt and skew, mounting fits, cage and flange interactions. The representation includes both steady state and time transient simulation of thermal interactions internal to and coupled with the surroundings of the bearing. A sample problem illustrating program use is presented.