Fiber optic engine for micro projection display.

PubMed

Arabi, Hesam Edin; An, Sohee; Oh, Kyunghwan

2010-03-01

A novel compact optical engine for a micro projector display is experimentally demonstrated, which is composed of RGB light sources, a tapered 3 x 1 Fiber Optic Color Synthesizer (FOCS) along with a fiberized ball-lens, and a two dimensional micro electromechanical scanning mirror. In the proposed optical engine, we successfully employed an all-fiber beam shaping technique combining optical fiber taper and fiberized ball lens that can render a narrow beam and enhance the resolution of the screened image in the far field. Optical performances of the proposed device assembly are investigated in terms of power loss, collimating strength of the collimator assembly, and color gamut of the output.

View of javelin and golf ball on lunar surface during Apollo 14 EVA

NASA Technical Reports Server (NTRS)

1971-01-01

View shows the javelin and golf ball used by Astronaut Alan B. Shepard Jr., Apollo 14 commander, during the mission's second extravehicular activity (EVA-2) on Feb. 6, 1971. Just to the left of center lies the javelin, with the golf ball just below it, almost perpendicular to it. Dark colored trails are the results of tracks made by the lunar overshoes of the astronauts and the wheels of the Modularized Equipment Transporter (MET). This photograph was made through the right window of the Lunar Module, looking northwest.

Naval Ship Maintenance: An Analysis of the Dutch Shipbuilding Industry Using the Knowledge Value Added, Systems Dynamics, and Integrated Risk Management Methodologies

DTIC Science & Technology

2012-10-10

functions) that you define as important outputs of the model. Think of the Monte Carlo simulation approach as picking golf balls out of a large...the large model as a very large basket, wherein many baby baskets reside. Each baby basket has its own set of colored golf balls that are bouncing...around. Sometimes these baby baskets are linked with each other (if there is a correlation between the variables), forcing the golf balls to bounce in

A low-cost, computer-interfaced drawing pad for FMRI studies of dysgraphia and dyslexia.

PubMed

Reitz, Frederick; Richards, Todd; Wu, Kelvin; Boord, Peter; Askren, Mary; Lewis, Thomas; Berninger, Virginia

2013-04-17

We have developed a pen and writing tablet for use by subjects during fMRI scanning. The pen consists of two jacketed, multi-mode optical fibers routed to the tip of a hollowed-out ball-point pen. The pen has been further modified by addition of a plastic plate to maintain a perpendicular pen-tablet orientation. The tablet is simply a non-metallic frame holding a paper print of continuously varying color gradients. The optical fibers are routed out of the MRI bore to a light-tight box in an adjacent control room. Within the box, light from a high intensity LED is coupled into one of the fibers, while the other fiber abuts a color sensor. Light from the LED exits the pen tip, illuminating a small spot on the tablet, and the resulting reflected light is routed to the color sensor. Given a lookup table of position for each color on the tablet, the coordinates of the pen on the tablet may be displayed and digitized in real-time. While simple and inexpensive, the system achieves sufficient resolution to grade writing tasks testing dysgraphic and dyslexic phenomena.

View of javelin and golf ball on lunar surface during Apollo 14 EVA

NASA Image and Video Library

1971-02-06

AS14-66-9337 (6 Feb. 1971) --- This view shows the "javelin" and golf ball used by astronaut Alan B. Shepard Jr., commander, during the mission's second extravehicular activity (EVA) on Feb. 6, 1971. Just to the left of center lies the "javelin", with the golf ball just below it, almost perpendicular to it. Dark colored trails are the results of tracks made by the lunar overshoes of the astronauts and the wheels of the modular equipment transporter (MET). This photograph was made through the right window of the Lunar Module (LM), looking northwest.

16 CFR 1117.5 - Information that must be reported and to whom.

Code of Federal Regulations, 2010 CFR

2010-01-01

... SAFETY ACT REGULATIONS REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND... (including any labeling and warnings), a description of the marble, small ball, latex balloon or other small...

How does gravity save or kill Q-balls?

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

Tamaki, Takashi; Sakai, Nobuyuki; Department of Education, Yamagata University, Yamagata 990-8560

2011-02-15

We explore stability of gravitating Q-balls with potential V{sub 4}({phi})=(m{sup 2}/2){phi}{sup 2}-{lambda}{phi}{sup 4}+({phi}{sup 6}/M{sup 2}) via catastrophe theory, as an extension of our previous work on Q-balls with potential V{sub 3}({phi})=(m{sup 2}/2){phi}{sup 2}-{mu}{phi}{sup 3}+{lambda}{phi}{sup 4}. In flat spacetime Q-balls with V{sub 4} in the thick-wall limit are unstable and there is a minimum charge Q{sub min}, where Q-balls with Q

Inserts Automatically Lubricate Ball Bearings

NASA Technical Reports Server (NTRS)

Hager, J. A.

1983-01-01

Inserts on ball-separator ring of ball bearings provide continuous film of lubricant on ball surfaces. Inserts are machined or molded. Small inserts in ball pockets provide steady supply of lubricant. Technique is utilized on equipment for which maintenance is often poor and lubrication interval is uncertain, such as household appliances, automobiles, and marine engines.

Gas-Bearing Crucible for Shot Tower

NASA Technical Reports Server (NTRS)

Youngberg, C. L.; Miller, C. G.; Stephens, J. B.; Finnerty, A. A.

1983-01-01

Device protects molten drops from contamination and distortion. Gas flowing through levitator tube levitates small balls while they melt. Gas heated by filament extending through center of tube. Gas bearing crucible on tube has concave configuration to hold single relatively large ball or many recesses to hold many small balls. By time spheres reach foam, they are cooled sufficiently by radiation to retain their shape.

Effect of Practicing Soccer Juggling With Different Sized Balls Upon Performance, Retention, and Transfer to Ball Reception.

PubMed

Raastad, Olav; Aune, Tore Kristian; van den Tillaar, Roland

2016-10-01

The aim of this study was to investigate if making the skill acquisition phase more difficult or easier would enhance performance in soccer juggling, and if this practice has a positive intertask transfer effect to ball reception performance. Twenty-two adolescent soccer players were tested in juggling a soccer ball and in the control of an approaching ball at a pre, post and retention test. The participants were randomly divided in a small ball size and bigger ball size training group that both trained four times per week for 6 weeks. At the post and retention test both groups enhanced performance in soccer juggling test with no difference between groups and no increase in ball reception performance at these tests. It was concluded that about intra task transfer and retention of soccer juggling skills, it does not matter if you increase (small balls) or decrease the difficulty (larger balls) when using the same amount of practice time within the skill acquisition phase in soccer juggling. In addition that for ball juggling and ball reception (inter task) these two tasks differ too much in afferent information and movement characteristics that no positive transfer between these two skills no positive intertask transfer can be expected.

Flare angles measured with ball gage

NASA Technical Reports Server (NTRS)

Cleghorn, D.; Wall, W. A.

1968-01-01

Precision tungsten carbide balls measure the internal angle of flared joints. Measurements from small and large balls in the flare throat to an external reference point are made. The difference in distances and diameters determine the average slope of the flare between the points of ball contact.

SmallSat Innovations for Planetary Science

NASA Astrophysics Data System (ADS)

Weinberg, Jonathan; Petroy, Shelley; Roark, Shane; Schindhelm, Eric

2017-10-01

As NASA continues to look for ways to fly smaller planetary missions such as SIMPLEX, MoO, and Venus Bridge, it is important that spacecraft and instrument capabilities keep pace to allow these missions to move forward. As spacecraft become smaller, it is necessary to balance size with capability, reliability and payload capacity. Ball Aerospace offers extensive SmallSat capabilities matured over the past decade, utilizing our broad experience developing mission architecture, assembling spacecraft and instruments, and testing advanced enabling technologies. Ball SmallSats inherit their software capabilities from the flight proven Ball Configurable Platform (BCP) line of spacecraft, and may be tailored to meet the unique requirements of Planetary Science missions. We present here recent efforts in pioneering both instrument miniaturization and SmallSat/sensorcraft development through mission design and implementation. Ball has flown several missions with small, but capable spacecraft. We also have demonstrated a variety of enhanced spacecraft/instrument capabilities in the laboratory and in flight to advance autonomy in spaceflight hardware that can enable some small planetary missions.

Flexure Bearing Reduces Startup Friction

NASA Technical Reports Server (NTRS)

Clingman, W. Dean

1991-01-01

Design concept for ball bearing incorporates small pieces of shim stock, wire spokes like those in bicycle wheels, or other flexing elements to reduce both stiction and friction slope. In flexure bearing, flexing elements placed between outer race of ball bearing and outer ring. Elements flex when ball bearings encounter small frictional-torque "bumps" or even larger ones when bearing balls encounter buildups of grease on inner or outer race. Flexure of elements reduce high friction slopes of "bumps", helping to keep torque between outer ring and inner race low and more nearly constant. Concept intended for bearings in gimbals on laser and/or antenna mirrors.

Do Red and Blue Uniforms Matter in Football and Handball Penalties?

PubMed

Krenn, Bjoern; Pernhaupt, Niklas; Handsteiner, Markus

2017-12-01

Past research has revealed ambiguous results on the impact of red uniforms in sports competition. The current study was aimed at analyzing the role of red and blue uniforms in football and handball penalties. Two experiments were conducted using a within subjects design, where participants rated uniform color-manipulated video clips. In the first study, participants (n = 39) watched footage of football players kicking a penalty, whereas in the second study (n = 118) videos of handball penalty takers, handball goalkeepers and football goalkeepers preparing themselves to score/save a penalty were shown. Participants rated player's/goalkeeper's level of confidence and the expected position of the ball crossing the goal line in the first experiment and additionally the probability of scoring the penalty against the goalkeepers in the second experiment. The videos stopped at the point where the ball was leaving the foot and hand respectively. Results did not show any beneficial impact of red uniforms. Rather, football players wearing blue were rated to kick the ball higher. The study contradicts any positive effect of red versus blue uniforms in the context of football and handball penalties, which emphasizes the need of searching for potential moderators of color's impact on human behavior.

Quality characteristic of liquid smoked straw mushroom (Volvariella volvacea) ball during storage

NASA Astrophysics Data System (ADS)

Kurniawan, C. W.; Atmaka, W.; Manuhara, G. J.; Sanjaya, A. P.

2018-01-01

Straw mushroom (Volvariella volvacea) ball was soaked for 15, 30, and 45 minutes with the concentration level 1%, 2%, and 3% (v/v) of the coconut shell liquid smoke. The chemical characteristics (water contains, total phenol, carbonil contains, total-N, TVB-N, and pH), microbiological characteristics (Total Plate Count), and sensory characteristics (color, flavor, taste, texture, and overalls) of the liquid smoked straw mushroom ball during 14 days storage at freezing temperature were investigated. The result showed that the water content and TVB-N were decreased after soaked and were increased after storaged. On the other hand, the result of total phenol, carbonyl content, and Total-N were increased after soaked and were decreased after storage. The level of pH and Total Plate Count of the straw mushroom ball were decreased during storage. Due to the sensory characteristics of the straw mushroom ball, the panelists provide high values for the straw mushroom ball which was soaked in 3% concentration level with 30 minutes soaked time. The best-soaked treatment was by soaked at 30 minutes with 3% concentration level liquid smoke. The straw mushroom ball has 70.95±0.10% water contains; 0.32±0.02% total phenol; 1.08±0.22% carbonyl contains; and 2.29±0.07% total-N.

Transorbital therapy delivery: phantom testing

NASA Astrophysics Data System (ADS)

Ingram, Martha-Conley; Atuegwu, Nkiruka; Mawn, Louise; Galloway, Robert L.

2011-03-01

We have developed a combined image-guided and minimally invasive system for the delivery of therapy to the back of the eye. It is composed of a short 4.5 mm diameter endoscope with a magnetic tracker embedded in the tip. In previous work we have defined an optimized fiducial placement for accurate guidance to the back of the eye and are now moving to system testing. The fundamental difficulty in testing performance is establishing a target in a manner which closely mimics the physiological task. We have to have a penetrable material which obscures line of sight, similar to the orbital fat. In addition we need to have some independent measure of knowing when a target has been reached to compare to the ideal performance. Lastly, the target cannot be rigidly attached to the skull phantom since the optic nerve lies buried in the orbital fat. We have developed a skull phantom with white cloth stellate balls supporting a correctly sized globe. Placed in the white balls are red, blue, orange and yellow balls. One of the colored balls has been soaked in barium to make it bright on CT. The user guides the tracked endoscope to the target as defined by the images and tells us its color. We record task accuracy and time to target. We have tested this with 28 residents, fellows and attending physicians. Each physician performs the task twice guided and twice unguided. Results will be presented.

Rolling-element fatigue life of AMS 5900 balls

NASA Technical Reports Server (NTRS)

Parker, R. J.

1983-01-01

The rolling-element fatigue life of AMS 5900 12.7-mm (1/2-in.) dia was determined in five-ball fatigue testers. The 10% life with the warm headed AMS 5900 balls was equivalent to that of AMS 5749 and over eight times that of AISI M-50. The AMS balls fabricated by cold heading had small surface cracks which initiated fatigue spalls where these cracks were crossed by running tracks. The cold-headed AMS 5900 balls had a 10% fatigue life an order of magnitude less than that of the warm headed balls even when failures on the cold headed balls at visible surface cracks were omitted.

Neutrinos from the terrestrial passage of supersymmetric dark-matter Q-balls

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

Kusenko, Alexander; Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568; Shoemaker, Ian M.

2009-07-15

Supersymmetry implies that stable nontopological solitons, Q-balls, could form in the early universe and could make up all or part of dark matter. We show that the relic Q-balls passing through Earth can produce a detectable neutrino flux. The peculiar zenith angle dependence and a small annual modulation of this flux can be used as signatures of dark-matter Q-balls.

Color from hierarchy: Diverse optical properties of micron-sized spherical colloidal assemblies.

PubMed

Vogel, Nicolas; Utech, Stefanie; England, Grant T; Shirman, Tanya; Phillips, Katherine R; Koay, Natalie; Burgess, Ian B; Kolle, Mathias; Weitz, David A; Aizenberg, Joanna

2015-09-01

Materials in nature are characterized by structural order over multiple length scales have evolved for maximum performance and multifunctionality, and are often produced by self-assembly processes. A striking example of this design principle is structural coloration, where interference, diffraction, and absorption effects result in vivid colors. Mimicking this emergence of complex effects from simple building blocks is a key challenge for man-made materials. Here, we show that a simple confined self-assembly process leads to a complex hierarchical geometry that displays a variety of optical effects. Colloidal crystallization in an emulsion droplet creates micron-sized superstructures, termed photonic balls. The curvature imposed by the emulsion droplet leads to frustrated crystallization. We observe spherical colloidal crystals with ordered, crystalline layers and a disordered core. This geometry produces multiple optical effects. The ordered layers give rise to structural color from Bragg diffraction with limited angular dependence and unusual transmission due to the curved nature of the individual crystals. The disordered core contributes nonresonant scattering that induces a macroscopically whitish appearance, which we mitigate by incorporating absorbing gold nanoparticles that suppress scattering and macroscopically purify the color. With increasing size of the constituent colloidal particles, grating diffraction effects dominate, which result from order along the crystal's curved surface and induce a vivid polychromatic appearance. The control of multiple optical effects induced by the hierarchical morphology in photonic balls paves the way to use them as building blocks for complex optical assemblies--potentially as more efficient mimics of structural color as it occurs in nature.

Color from hierarchy: Diverse optical properties of micron-sized spherical colloidal assemblies

PubMed Central

Vogel, Nicolas; Utech, Stefanie; England, Grant T.; Shirman, Tanya; Phillips, Katherine R.; Koay, Natalie; Burgess, Ian B.; Kolle, Mathias; Weitz, David A.; Aizenberg, Joanna

2015-01-01

Materials in nature are characterized by structural order over multiple length scales have evolved for maximum performance and multifunctionality, and are often produced by self-assembly processes. A striking example of this design principle is structural coloration, where interference, diffraction, and absorption effects result in vivid colors. Mimicking this emergence of complex effects from simple building blocks is a key challenge for man-made materials. Here, we show that a simple confined self-assembly process leads to a complex hierarchical geometry that displays a variety of optical effects. Colloidal crystallization in an emulsion droplet creates micron-sized superstructures, termed photonic balls. The curvature imposed by the emulsion droplet leads to frustrated crystallization. We observe spherical colloidal crystals with ordered, crystalline layers and a disordered core. This geometry produces multiple optical effects. The ordered layers give rise to structural color from Bragg diffraction with limited angular dependence and unusual transmission due to the curved nature of the individual crystals. The disordered core contributes nonresonant scattering that induces a macroscopically whitish appearance, which we mitigate by incorporating absorbing gold nanoparticles that suppress scattering and macroscopically purify the color. With increasing size of the constituent colloidal particles, grating diffraction effects dominate, which result from order along the crystal’s curved surface and induce a vivid polychromatic appearance. The control of multiple optical effects induced by the hierarchical morphology in photonic balls paves the way to use them as building blocks for complex optical assemblies—potentially as more efficient mimics of structural color as it occurs in nature. PMID:26290583

NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT ...

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

NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT EDGE IS THE SINGLE CYLINDER “HOT SHOT” ENGINE THAT PROVIDED POWER FOR THE MILL. JUST IN FRONT OF IT IS AN ARRASTRA. AT CENTER IS THE BALL MILL AND SECONDARY ORE BIN. JUST TO THE RIGHT OF THE BALL MILL IS A RAKE CLASSIFIER, AND TO THE RIGHT ARE THE CONCENTRATION TABLES. WARM SPRINGS CAMP IS IN THE DISTANCE. SEE CA-292-17 (CT) FOR IDENTICAL COLOR TRANSPARENCY. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

Ready for the Cosmic Ball

NASA Image and Video Library

2006-04-26

Something appears to be peering through a shiny red mask, in this new false-colored image from NASA Spitzer Space Telescope. The mysterious blue eyes are actually starlight from the cores of two merging galaxies, called NGC 2207 and IC 2163.

A novel and easy FxCycle™ violet based flow cytometric method for simultaneous assessment of DNA ploidy and six-color immunophenotyping.

PubMed

Tembhare, Prashant; Badrinath, Yajamanam; Ghogale, Sitaram; Patkar, Nikhil; Dhole, Nilesh; Dalavi, Pooja; Kunder, Nikesh; Kumar, Ashok; Gujral, Sumeet; Subramanian, P G

2016-03-01

Abnormal DNA ploidy is a valuable prognostic factor in many neoplasms, especially in hematological neoplasms like B-cell acute lymphoblastic leukemia (B-ALL) and multiple myeloma (MM). Current methods of flow-cytometric (FC) DNA-ploidy evaluation are either technically difficult or limited to three- to four-color immunophenotyping and hence, challenging to evaluate DNA-ploidy in minute tumor population with background rich of its normal counterpart cells and other hematopoietic cells. We standardized a novel sensitive and easy method of simultaneous evaluation of six- to seven-color immunophenotyping and DNA-ploidy using a dye-FxCycle Violet (FCV). Linearity, resolution, and coefficient of variation (CV) for FCV were studied using chicken erythrocyte nuclei. Ploidy results of FCV were compared with Propidium iodide (PI) in 20 samples and intra-assay variation for FCV was studied. Using this six-color immunophenotyping & FCV-protocol DNA-ploidy was determined in bone-marrow samples from 124 B-ALL & 50 MM patients. Dilution experiment was also conducted to determine the sensitivity in detection of aneuploidy in minute tumor population. FCV revealed high linearity and resolution in 450/50 channel. On comparison with PI, CV of Go/G1-peak with FCV (mean-CV 4.1%) was slightly higher than PI (mean-CV 2.9%) but had complete agreement in ploidy results. Dilution experiment showed that aneuploidy could be accurately detected up to the limit of 0.01% tumor cells. Intra-assay variation was very low with CV of 0.005%. In B-ALL, hypodiploidy was noted in 4%, hyperdiploidy in 24%, near-hyperdiploidy in 13% and remaining 59% were diploid. In MM, hypodiploidy was in 2%, hyperdiploidy in 58%, near-hyperdiploidy in 8% and remaining 30% were diploid. FCV-based DNA-ploidy method is a sensitive and easy method for simultaneous evaluation of six-color immunophenotyping and DNA analysis. It is useful in DNA-ploidy evaluation of minute tumor population in cases like minimal residual disease and MM precursor conditions. © 2015 International Society for Advancement of Cytometry.

The Earth's Seasons in 3-D--Part 1.

ERIC Educational Resources Information Center

Eckroth, Charles A.

1993-01-01

This article describes a teaching aid made from four colored foam balls mounted on a stiff wire circle used to teach about the changing seasons and earth temperature fluctuations. The spheres represent the Earth at the solstice and equinox positions. (MVL)

Unit Cells

ERIC Educational Resources Information Center

Olsen, Robert C.; Tobiason, Fred L.

1975-01-01

Describes the construction of unit cells using clear plastic cubes which can be disassembled, and one inch cork balls of various colors, which can be cut in halves, quarters, or eighths, and glued on the inside face of the cube, thus simulating a unit cell. (MLH)

Thulium fiber laser lithotripsy using small spherical distal fiber tips

NASA Astrophysics Data System (ADS)

Wilson, Christopher R.; Hardy, Luke A.; Kennedy, Joshua D.; Irby, Pierce B.; Fried, Nathaniel M.

2016-02-01

This study tests a 100-μm-core fiber with 300-μm-diameter ball tip during Thulium fiber laser (TFL) lithotripsy. The TFL was operated at 1908 nm wavelength with 35-mJ pulse energy, 500-μs pulse duration, and 300-Hz pulse rate. Calcium oxalate/phosphate stone samples were weighed, laser procedure times measured, and ablation rates calculated for ball tip fibers, with comparison to bare tip fibers. Photographs of ball tips were taken before and after each procedure to observe ball tip degradation and determine number of procedures completed before need to replace fiber. Saline irrigation rates and ureteroscope deflection were measured with and without TFL fiber present. There was no statistical difference (P > 0.05) between stone ablation rates for single-use ball tip fiber (1.3 +/- 0.4 mg/s) (n=10), multiple-use ball tip fiber (1.3 +/- 0.5 mg/s) (n=44), and conventional single-use bare tip fibers (1.3 +/- 0.2 mg/s) (n=10). Ball tip durability varied widely, but fibers averaged > 4 stone procedures before decline in stone ablation rates due to mechanical damage at front surface of ball tip. The small fiber diameter did not impact ureteroscope deflection or saline flow rates. The miniature ball tip fiber may provide a cost-effective design for safe fiber insertion through the ureteroscope working channel and the ureter without risk of scope damage or tissue perforation, and without compromising stone ablation efficiency during TFL ablation of kidney stones.

Coalification of organic matter in coal balls of the Pennsylvanian (upper Carboniferous) of the Illinois Basin, United States

USGS Publications Warehouse

Lyons, P.C.; Thompson, C.L.; Hatcher, P.G.; Brown, F.W.; Millay, M.A.; Szeverenyi, N.; Maciel, G.E.

1984-01-01

An evaluation was made of the degree of coalification of two coal balls from the Illinois Basin of the Pennsylvanian (upper Carboniferous) of the United States. Previous interpretations are mainly misleading and contradictory, primarily because of the assumption that the brown color and exceptional cellular and subcellular preservation typical of American coal balls imply chemical preservation of cellulose and lignin, the primary components of peat. Xylem tissue from a medullosan seed fern contained in a coal ball and the coal attached to the coal ball from the Calhoun coal bed, Mattoon Formation, Illinois, was analyzed by elemental, petrographic, and nuclear magnetic resonance (NMR) techniques to determine the degree of coalification. The NMR and elemental data indicate the lack of cellulose and lignin and a probable rank of high-volatile C bituminous coal. These data corroborate data for a coal ball from the Herrin (No. 6) coal bed (Carbondale Formation, Middle Pennsylvanian) and support our hypothesis that the organic matter in coal balls of the Pennsylvanian strata of the United States is coalified to about the same degree as the surrounding coal. Data presented show a range of lower reflectances for xylem tissue and vitrinite in the analyzed coal balls compared with vitrinite in the attached coal. The data reported indicate that physical preservation of organic matter in coal balls does not imply chemical preservation. Also our study supports the hypothesis that compactional (static load) pressure is not a prerequisite for coalification up to a rank of high-volatile C bituminous coal. A whole-rock analysis of the Calhoun coal ball indicates a similarity to other carbonate coal balls from the United States. It consists primarily of calcium carbonate and 1-2% organic matter; silica and alumina together make up less than 0.5%, indicating the lack of minerals such as quartz and clays. ?? 1984.

Idea Bank.

ERIC Educational Resources Information Center

Talesnick, Irwin, Ed.

1984-01-01

Provides innovative ideas in biology, chemistry, and physics on the following topics: enzyme decomposition; chemical waste; time measurement; acid-base color magic; ball bouncing properties; heat; cell theory; and specimen boxes. Materials and procedures are listed when appropriate along with hints for expanding these ideas and investigations. (JM)

Color group selection for computer interfaces

NASA Astrophysics Data System (ADS)

Lyons, Paul; Moretti, Giovanni; Wilson, Mark

2000-06-01

We describe a low-impact method for coloring interfaces harmoniously. The method uses a model that characterizes the overall image including the need for distinguishability between interface components. The degree of visual distinction between one component and other components, and its color strength (which increases with its importance and decreases with its size and longevity), are used in generating a rigid ball-and-stick 'color molecule,' which represents the color relationships between the interface components. The shape of the color molecule is chosen to conform to standard principles of color harmony (like colors harmonize, complementary colors harmonize, cycles in the color space harmonize, and so on). The color molecule's shape is fixed, but its position and orientation within the perceptually uniform color solid are not. The end user of the application chooses a new color scheme for the complete interface by repositioning the molecule within the color space. The molecule's shape and rigidity, and the space's perceptual uniformity, ensures the distinguishability and color harmony of the components are maintained. The system produces a selection of color schemes which often include subtle 'nameless' colors that people rarely choose using conventional color controls, but which blend smoothly into a harmonious color scheme. A new set of equally harmonious color schemes only requires repositioning the color molecule within the space.

The Efficiency of Small Bearings in Instruments of the Type Used in Aircraft

NASA Technical Reports Server (NTRS)

Norton, F H

1921-01-01

This report deals with the construction and properties of bearings and pivots for use in instruments. The static and running friction for both thrust and radial loads was determined for a number of conical pivots and cylindrical and ball bearings. The static rocking friction was also measured for several conical and ball bearings under a heavy load, especially to determine their suitability for use in N. P. L. (National Physical Laboratory) type wind tunnel balance. In constructing conical pivots and sockets it was found that the pivots should be hardened and highly polished, preferably with a revolving lap, and that the sockets should be made by punching with a hardened and polished punch. It was found that for a light load the conical pivots give less friction than any other type, and their wearing qualities when hardened are excellent. Very small ball bearings are unsatisfactory because the proportional accuracy of the balls and races is not high enough to insure smooth running. For rocking pivots under heavy loads it was found that a ball-and-socket bearing, consisting of a hemispherical socket and a sphere of smaller diameter concentric with it, with a row of small balls resting between the two, was superior to a pivot resting in a socket. It was found that vibration such as occurs in an airplane will greatly reduce the static friction of a pivot or bearing, in some cases to as little as one-twentieth of its static value.

Compact Q-balls and Q-shells in a scalar electrodynamics

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

Arodz, H.; Lis, J.

2009-02-15

We investigate spherically symmetric nontopological solitons in electrodynamics with a scalar field self-interaction U{approx}|{psi}| taken from the complex signum-Gordon model. We find Q-balls for small absolute values of the total electric charge Q, and Q-shells when |Q| is large enough. In both cases the charge density exactly vanishes outside certain compact regions in the three-dimensional space. The dependence of the total energy E of small Q-balls on the total electric charge has the form E{approx}|Q|{sup 5/6}, while in the case of very large Q-shells, E{approx}|Q|{sup 7/6}.

Low conductive support for thermal insulation of a sample holder of a variable temperature scanning tunneling microscope

NASA Astrophysics Data System (ADS)

Hanzelka, Pavel; Vonka, Jakub; Musilova, Vera

2013-08-01

We have designed a supporting system to fix a sample holder of a scanning tunneling microscope in an UHV chamber at room temperature. The microscope will operate down to a temperature of 20 K. Low thermal conductance, high mechanical stiffness, and small dimensions are the main features of the supporting system. Three sets of four glass balls placed in vertices of a tetrahedron are used for thermal insulation based on small contact areas between the glass balls. We have analyzed the thermal conductivity of the contacts between the balls mutually and between a ball and a metallic plate while the results have been applied to the entire support. The calculation based on a simple model of the setup has been verified with some experimental measurements. In comparison with other feasible supporting structures, the designed support has the lowest thermal conductance.

Low conductive support for thermal insulation of a sample holder of a variable temperature scanning tunneling microscope.

PubMed

Hanzelka, Pavel; Vonka, Jakub; Musilova, Vera

2013-08-01

We have designed a supporting system to fix a sample holder of a scanning tunneling microscope in an UHV chamber at room temperature. The microscope will operate down to a temperature of 20 K. Low thermal conductance, high mechanical stiffness, and small dimensions are the main features of the supporting system. Three sets of four glass balls placed in vertices of a tetrahedron are used for thermal insulation based on small contact areas between the glass balls. We have analyzed the thermal conductivity of the contacts between the balls mutually and between a ball and a metallic plate while the results have been applied to the entire support. The calculation based on a simple model of the setup has been verified with some experimental measurements. In comparison with other feasible supporting structures, the designed support has the lowest thermal conductance.

Area deficits and the Bel–Robinson tensor

NASA Astrophysics Data System (ADS)

Jacobson, Ted; Senovilla, José M. M.; Speranza, Antony J.

2018-04-01

The first law of causal diamonds relates the area deficit of a small ball relative to flat space to the matter energy density it contains. At second order in the Riemann normal coordinate expansion, this energy density should receive contributions from the gravitational field itself. In this work, we study the second-order area deficit of the ball in the absence of matter and analyze its relation to possible notions of gravitational energy. In the small ball limit, a reasonable expectation for any proposed gravitational energy functional is that it evaluate to the Bel–Robinson energy density W in vacuum spacetimes. A direct calculation of the area deficit reveals a result that is not simply proportional to W. We discuss how the deviation from W is related to ambiguities in defining the shape of the ball in curved space, and provide several proposals for fixing these shape ambiguities.

Detection of small-size solder ball defects through heat conduction analysis

NASA Astrophysics Data System (ADS)

Zhou, Xiuyun; Chen, Yaqiu; Lu, Xiaochuan

2018-02-01

Aiming to solve the defect detection problem of a small-size solder ball in the high density chip, heat conduction analysis based on eddy current pulsed thermography is put forward to differentiate various defects. With establishing the 3D finite element model about induction heating, defects such as cracks and void can be distinguished by temperature difference resulting from heat conduction. Furthermore, the experiment of 0.4 mm-diameter solder balls with different defects is carried out to prove that crack and void solder can be distinguished. Three kinds of crack length on a gull-wing pin are selected, including 0.24 mm, 1.2 mm, and 2.16 mm, to verify that the small defect can be discriminated. Both the simulation study and experiment result show that the heat conduction analysis method is reliable and convenient.

The effects of ball size distribution on attritor efficiency

NASA Astrophysics Data System (ADS)

Cook, T. M.; Courtney, T. H.

1995-09-01

A study was undertaken to determine how media dynamics are altered when differently sized grinding balls are used in an attritor. Cinematographic techniques identify the extent of segregation/mixing of the differently sized balls within the attritor as a function of impeller rotational velocity and small ball number fraction. This permits determination of rotational velocities needed to most efficiently use the tactic of milling with differently sized media. Cinematographic observations show that the close-packed media array, assumed when balls of the same size are used for milling, is disrupted when differently sized balls are used. Monitoring powder particle numbers as a function of milling time for the situations when the same and differently sized balls are used can be used to assess relative milling efficiencies. Results indicate powder deformation, fracture, and welding are enhanced through employment of differently sized balls. This conclusion is reinforced by observations of microstructural characteristics of powder processed with the different type of media.

A Steel Ball Surface Quality Inspection Method Based on a Circumferential Eddy Current Array Sensor.

PubMed

Zhang, Huayu; Xie, Fengqin; Cao, Maoyong; Zhong, Mingming

2017-07-01

To efficiently inspect surface defects on steel ball bearings, a new method based on a circumferential eddy current array (CECA) sensor was proposed here. The best probe configuration, in terms of the coil quality factor (Q-factor), magnetic field intensity, and induced eddy current density on the surface of a sample steel ball, was determined using 3-, 4-, 5-, and 6-coil probes, for analysis and comparison. The optimal lift-off from the measured steel ball, the number of probe coils, and the frequency of excitation current suitable for steel ball inspection were obtained. Using the resulting CECA sensor to inspect 46,126 steel balls showed a miss rate of ~0.02%. The sensor was inspected for surface defects as small as 0.05 mm in width and 0.1 mm in depth.

Q-balls in flat potentials

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

Copeland, Edmund J.; Tsumagari, Mitsuo I.

2009-07-15

We study the classical and absolute stability of Q-balls in scalar field theories with flat potentials arising in both gravity-mediated and gauge-mediated models. We show that the associated Q-matter formed in gravity-mediated potentials can be stable against decay into their own free particles as long as the coupling constant of the nonrenormalizable term is small, and that all of the possible three-dimensional Q-ball configurations are classically stable against linear fluctuations. Three-dimensional gauge-mediated Q-balls can be absolutely stable in the thin-wall limit, but are completely unstable in the thick-wall limit.

The Energy Cost of Running with the Ball in Soccer.

PubMed

Piras, Alessandro; Raffi, Milena; Atmatzidis, Charalampos; Merni, Franco; Di Michele, Rocco

2017-11-01

Running with the ball is a soccer-specific activity frequently used by players during match play and training drills. Nevertheless, the energy cost (EC) of on-grass running with the ball has not yet been determined. The purpose of this study was therefore to assess the EC of constant-speed running with the ball, and to compare it with the EC of normal running. Eight amateur soccer players performed two 6- min runs at 10 km/h on artificial turf, respectively with and without the ball. EC was measured with indirect calorimetry and, furthermore, estimated with a method based on players' accelerations measured with a GPS receiver. The EC measured with indirect calorimetry was higher in running with the ball (4.60±0.42 J/kg/m) than in normal running (4.19±0.33 J/kg/m), with a very likely moderate difference between conditions. Instead, a likely small difference was observed between conditions for EC estimated from GPS data (4.87±0.07 vs. 4.83±0.08 J/kg/m). This study sheds light on the energy expenditure of playing soccer, providing relevant data about the EC of a typical soccer-specific activity. These findings may be a reference for coaches to precisely determine the training load in drills with the ball, such as soccer-specific circuits or small-sided games. © Georg Thieme Verlag KG Stuttgart · New York.

Lessons: Science. Slime!

ERIC Educational Resources Information Center

VanCleave, Janice

2000-01-01

Describes a science activity in which students make a non-Newtonian fluid (slime), which has both solid and liquid properties. After reviewing the shape and volume of solids and volume of liquids, students make the slime using glue, liquid starch, and food coloring. They can experiment by rolling and dropping slime balls and by pulling the slime…

The Stair-Step Atom.

ERIC Educational Resources Information Center

Jordan, Thomas M.; And Others

1992-01-01

Presents a model of a generic atom that is used to represent the movement of electrons from lower to higher levels and vice-versa due to excitation and de-excitation of the atom. As the process of de-excitation takes place, photons represented by colored ping-pong balls are emitted, indicating the emission of light. (MDH)

Detection of Phase Transition in Generalized Pólya Urn in Information Cascade Experiment

NASA Astrophysics Data System (ADS)

Hino, Masafumi; Irie, Yosuke; Hisakado, Masato; Takahashi, Taiki; Mori, Shintaro

2016-03-01

We propose a method of detecting a phase transition in a generalized Pólya urn in an information cascade experiment. The method is based on the asymptotic behavior of the correlation C(t) between the first subject’s choice and the t + 1-th subject’s choice, the limit value of which, c ≡ limt to ∞ C(t), is the order parameter of the phase transition. To verify the method, we perform a voting experiment using two-choice questions. An urn X is chosen at random from two urns A and B, which contain red and blue balls in different configurations. Subjects sequentially guess whether X is A or B using information about the prior subjects’ choices and the color of a ball randomly drawn from X. The color tells the subject which is X with probability q. We set q in { 5/9,6/9,7/9,8/9} by controlling the configurations of red and blue balls in A and B. The (average) lengths of the sequence of the subjects are 63, 63, 54.0, and 60.5 for q in { 5/9,6/9,7/9,8/9} , respectively. We describe the sequential voting process by a nonlinear Pólya urn model. The model suggests the possibility of a phase transition when q changes. We show that c > 0 (= 0) for q = 5/9,6/9 (7/9,8/9) and detect the phase transition using the proposed method.

Performance of Small Bore 60NiTi Hybrid Ball Bearings: Preliminary Life Test Results

NASA Technical Reports Server (NTRS)

Dellacorte, Christopher; Howard, S. Adam

2016-01-01

Small bore (R8 size) hybrid ball bearings made with 60NiTi races and silicon nitride balls are under development for highly corrosive aerospace applications that are also exposed to heavy static (shock) loads. The target application is the vacuum pump used inside the wastewater recycling system on the International Space Station. To verify bearing longevity, life tests are run at 2000rpm for time periods up to 5000 hours. Accelerometers with data tracking are used to monitor operation and the bearings are disassembled and inspected at intervals to assess wear. Preliminary tests show that bearings made from 60NiTi are feasible for this aerospace and potentially other industrial applications that must endure similar operating environments.

Naphthalene emissions from moth repellents or toilet deodorant blocks determined using head-space and small-chamber tests.

PubMed

Jo, Wan-Kuen; Lee, Jong-Hyo; Lim, Ho-Jin; Jeong, Woo-Sik

2008-01-01

The present study investigated the emissions of naphthalene and other compounds from several different moth repellents (MRs) and one toilet deodorant block (TDB) currently sold in Korea, using a headspace analysis. The emission factors and emission rates of naphthalene were studied using a small-scale environmental chamber. Paper-type products emitted a higher concentration of the total volatile organic compounds (VOCs) (normalized to the weight of test piece) than ball-type products, which in turn emitted higher concentration than a gel-type product. In contrast, naphthalene was either the most or the second highest abundant compound for the four ball products, whereas for paper and gel products it was not detected or was detected at much lower levels. The abundance of naphthalene ranged between 18.4% and 37.3% for ball products. The results showed that the lower the air changes per hour (ACH) level was, the higher the naphthalene concentrations became. In general, a low ACH level suggests a low ventilation rate. The emission factor for naphthalene was nearly 100 times higher for a ball MR than for a gel or a paper MR. For the ball MR, the lower ACH level resulted in higher emission rate.

Application of a Saddle-Type Eddy Current Sensor in Steel Ball Surface-Defect Inspection.

PubMed

Zhang, Huayu; Zhong, Mingming; Xie, Fengqin; Cao, Maoyong

2017-12-05

Steel ball surface-defect inspection was performed by using a new saddle-type eddy current sensor (SECS), which included a saddle coil and a signal conditioning circuit. The saddle coil was directly wound on the steel ball's outer bracket in a semi-circumferential direction. Driven by a friction wheel, the test steel ball rotated in a one-dimensional direction, such that the steel ball surface was fully scanned by the SECS. There were two purposes for using the SECS in the steel ball inspection system: one was to reduce the complexity of the unfolding wheel of the surface deployment mechanism, and the other was to reduce the difficulty of sensor processing and installation. Experiments were carried out on bearing steel balls in diameter of 8 mm with three types of representative and typical defects by using the SECS, and the results showed that the inspection system can detect surface defects as small as 0.05 mm in width and 0.1 mm in depth with high-repetition detection accuracy, and the detection efficiency of 5 pcs/s, which meet the requirement for inspecting ISO grade 10 bearing steel balls. The feasibility of detecting steel ball surface defects by SECS was verified.

Subject-specific computer simulation model for determining elbow loading in one-handed tennis backhand groundstrokes.

PubMed

King, Mark A; Glynn, Jonathan A; Mitchell, Sean R

2011-11-01

A subject-specific angle-driven computer model of a tennis player, combined with a forward dynamics, equipment-specific computer model of tennis ball-racket impacts, was developed to determine the effect of ball-racket impacts on loading at the elbow for one-handed backhand groundstrokes. Matching subject-specific computer simulations of a typical topspin/slice one-handed backhand groundstroke performed by an elite tennis player were done with root mean square differences between performance and matching simulations of < 0.5 degrees over a 50 ms period starting from ball impact. Simulation results suggest that for similar ball-racket impact conditions, the difference in elbow loading for a topspin and slice one-handed backhand groundstroke is relatively small. In this study, the relatively small differences in elbow loading may be due to comparable angle-time histories at the wrist and elbow joints with the major kinematic differences occurring at the shoulder. Using a subject-specific angle-driven computer model combined with a forward dynamics, equipment-specific computer model of tennis ball-racket impacts allows peak internal loading, net impulse, and shock due to ball-racket impact to be calculated which would not otherwise be possible without impractical invasive techniques. This study provides a basis for further investigation of the factors that may increase elbow loading during tennis strokes.

Residual stresses in AM fabricated ball during a heating process

NASA Astrophysics Data System (ADS)

Burenin, A. A.; Murashkin, E. V.; Dats, E. P.

2018-05-01

The present study is devoted to the problem of residual stresses calculation in AM fabricated ball during heating. Strains of the ball are assumed to be small, which allows to use the apparatus of the theory of thermoelastoplastic akin to Prandtl and Reuss. The problem of the evolution of the field of residual stresses in the ball at a given temperature on its external border is solved. The heat conduction equation and the equilibrium equations may be independently integrated when the hypothesis of the insignificance of the coupled effects of thermal and mechanical processes is adopted. The fields of residual stresses and displacements are computed.

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

Lis, Jakub

In this paper, we investigate the Q-ball Ansatz in the baby Skyrme model. First, the appearance of peakons, i.e. solutions with extremely large absolute values of the second derivative at maxima, is analyzed. It is argued that such solutions are intrinsic to the baby Skyrme model and do not depend on the detailed form of a potential used in calculations. Next, we concentrate on compact nonspinning Q-balls. We show the failure of a small parameter expansion in this case. Finally, we explore the existence and parameter dependence of Q-ball solutions.

Temperature actuated shutdown assembly for a nuclear reactor

DOEpatents

Sowa, Edmund S.

1976-01-01

Three identical bimetallic disks, each shaped as a spherical cap with its convex side composed of a layer of metal such as molybdenum and its concave side composed of a metal of a relatively higher coefficient of thermal expansion such as stainless steel, are retained within flanges attached to three sides of an inner hexagonal tube containing a neutron absorber to be inserted into a nuclear reactor core. Each disk holds a metal ball against its normally convex side so that the ball projects partially through a hole in the tube located concentrically with the center of each disk; at a predetermined temperature an imbalance of thermally induced stresses in at least one of the disks will cause its convex side to become concave and its concave side to become convex, thus pulling the ball from the hole in which it is located. The absorber has a conical bottom supported by the three balls and is small enough in relation to the internal dimensions of the tube to allow it to slip toward the removed ball or balls, thus clearing the unremoved balls or ball so that it will fall into the reactor core.

Golf Ball

NASA Technical Reports Server (NTRS)

1998-01-01

The Ultra 500 Series golf balls, introduced in 1995 by Wilson Sporting Goods Company, has 500 dimples arranged in a pattern of 60 spherical triangles. The design employs NASA's aerodynamics technology analysis of air loads of the tank and Shuttle orbiter that was performed under the Space Shuttle External Tank program. According to Wilson, this technology provides 'the most symmetrical ball surface available, sustaining initial velocity longer and producing the most stable ball flight for unmatched accuracy and distance.' The dimples are in three sizes, shapes and depths mathematically positioned for the best effect. The selection of dimples and their placement optimizes the interaction of opposing forces of lift and drag. Large dimples reduce air drag, enhance lift, and maintain spin for distance. Small dimples prevent excessive lift that destabilizes the ball flight and the medium size dimples blend the other two.

Diaphragm disease: the limitation of laparoscopy and assessment of the small bowel for strictures using a ball bearing.

PubMed

Moffat, C E; Khyan, M K; Davies, C G; Ghauri, A S K; Ranaboldo, C J

2006-09-07

Diaphragm disease is a rare cause of intestinal obstruction that will be seen with increasing frequency with the widespread use of nonsteroidal anti-inflammatory drugs (NSAIDs). We present a case study of a patient with diaphragm disease where the diagnosis was not apparent at laparoscopy, and passage of a steel ball through the small intestine was required to identify all strictures present. A high index of suspicion, recognition of the limitations of conventional diagnostic aids, and the need to assess the full length of the small bowel are all important in the surgical management of this condition.

DETAIL OVERHEAD VIEW OF SECONDARY ORE BIN. CONVEYOR PLATFORM,TRAM TRESTLE, ...

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

DETAIL OVERHEAD VIEW OF SECONDARY ORE BIN. CONVEYOR PLATFORM,TRAM TRESTLE, AND LOADING PLATFORM. LOOKING SOUTHWEST. THE HOLE IN THE ORE BIN FLOOR CAN BE SEEN, AND BALL MILL FOUNDATION AT LOWER LEFT CORNER. SEE CA-291-47(CT) FOR IDENTICAL COLOR TRANSPARENCY. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

Flame balls dynamics in divergent channel

NASA Astrophysics Data System (ADS)

Fursenko, R.; Minaev, S.

2011-12-01

A three-dimensional reaction-diffusion model for lean low-Lewis-number premixed flames with radiative heat losses propagating in divergent channel is studied numerically. Effects of inlet gas velocity and heat-loss intensity on flame structure at low Lewis numbers are investigated. It is found that continuous flame front exists at small heat losses and the separate flame balls settled within restricted domain inside the divergent channel at large heat losses. It is shown that the time averaged flame balls coordinate may be considered as important characteristic analogous to coordinate of continuous flame stabilized in divergent channel.

Fluid Mechanics of Cricket and Tennis Balls

NASA Astrophysics Data System (ADS)

Mehta, Rabindra D.

2009-11-01

Aerodynamics plays a prominent role in defining the flight of a ball that is struck or thrown through the air in almost all ball sports. The main interest is in the fact that the ball can often deviate from its initial straight path, resulting in a curved, or sometimes an unpredictable, flight path. It is particularly fascinating that that not all the parameters that affect the flight of a ball are always under human influence. Lateral deflection in flight, commonly known as swing, swerve or curve, is well recognized in cricket and tennis. In tennis, the lateral deflection is produced by spinning the ball about an axis perpendicular to the line of flight, which gives rise to what is commonly known as the Magnus effect. It is now well recognized that the aerodynamics of sports balls are strongly dependent on the detailed development and behavior of the boundary layer on the ball's surface. A side force, which makes a ball curve through the air, can also be generated in the absence of the Magnus effect. In one of the cricket deliveries, the ball is released with the seam angled, which trips the laminar boundary layer into a turbulent state on that side. The turbulent boundary layer separates relatively late compared to the laminar layer on the other side, thereby creating a pressure difference and hence side force. The fluid mechanics of a cricket ball become very interesting at the higher Reynolds numbers and this will be discussed in detail. Of all the round sports balls, a tennis ball has the highest drag coefficient. This will be explained in terms of the contribution of the ``fuzz" drag and how that changes with Reynolds number and ball surface wear. It is particularly fascinating that, purely through historical accidents, small disturbances on the ball surface, such as the stitching on cricket balls and the felt cover on tennis balls are all about the right size to affect boundary layer transition and development in the Reynolds numbers of interest. The fluid mechanics of cricket and tennis balls will be discussed in detail with the help of latest test data, analyses and video clips.

Ball python nidovirus: a candidate etiologic agent for severe respiratory disease in Python regius.

PubMed

Stenglein, Mark D; Jacobson, Elliott R; Wozniak, Edward J; Wellehan, James F X; Kincaid, Anne; Gordon, Marcus; Porter, Brian F; Baumgartner, Wes; Stahl, Scott; Kelley, Karen; Towner, Jonathan S; DeRisi, Joseph L

2014-09-09

A severe, sometimes fatal respiratory disease has been observed in captive ball pythons (Python regius) since the late 1990s. In order to better understand this disease and its etiology, we collected case and control samples and performed pathological and diagnostic analyses. Electron micrographs revealed filamentous virus-like particles in lung epithelial cells of sick animals. Diagnostic testing for known pathogens did not identify an etiologic agent, so unbiased metagenomic sequencing was performed. Abundant nidovirus-like sequences were identified in cases and were used to assemble the genome of a previously unknown virus in the order Nidovirales. The nidoviruses, which were not previously known to infect nonavian reptiles, are a diverse order that includes important human and veterinary pathogens. The presence of the viral RNA was confirmed in all diseased animals (n = 8) but was not detected in healthy pythons or other snakes (n = 57). Viral RNA levels were generally highest in the lung and other respiratory tract tissues. The 33.5-kb viral genome is the largest RNA genome yet described and shares canonical characteristics with other nidovirus genomes, although several features distinguish this from related viruses. This virus, which we named ball python nidovirus (BPNV), will likely establish a new genus in Torovirinae subfamily. The identification of a novel nidovirus in reptiles contributes to our understanding of the biology and evolution of related viruses, and its association with lung disease in pythons is a promising step toward elucidating an etiology for this long-standing veterinary disease. Ball pythons are popular pets because of their diverse coloration, generally nonaggressive behavior, and relatively small size. Since the 1990s, veterinarians have been aware of an infectious respiratory disease of unknown cause in ball pythons that can be fatal. We used unbiased shotgun sequencing to discover a novel virus in the order Nidovirales that was present in cases but not controls. While nidoviruses are known to infect a variety of animals, this is the first report of a nidovirus recovered from any reptile. This report will enable diagnostics that will assist in determining the role of this virus in the causation of disease, which would allow control of the disease in zoos and private collections. Given its evolutionary divergence from known nidoviruses and its unique host, the study of reptile nidoviruses may further our understanding of related diseases and the viruses that cause them in humans and other animals. Copyright © 2014 Stenglein et al.

Hopkins during SPHERES Slosh Run

NASA Image and Video Library

2014-01-22

ISS038-E-033884 (22 Jan. 2014) --- In the International Space Station's Kibo laboratory, NASA astronaut Mike Hopkins, Expedition 38 flight engineer, holds a plastic container partially filled with green-colored water which will be used in a new experiment using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES, which are already on the station. For the SPHERES-Slosh experiment, two SPHERES robots are attached to opposite ends of a metal frame holding the plastic tank with the green-colored water. The new hardware for the SPHERES-Slosh study was delivered to the station aboard Orbital Sciences' Cygnus cargo craft on Jan. 12.

An asymmetric resonant coupling wireless power transmission link for Micro-Ball Endoscopy.

PubMed

Sun, Tianjia; Xie, Xiang; Li, Guolin; Gu, Yingke; Deng, Yangdong; Wang, Ziqiang; Wang, Zhihua

2010-01-01

This paper investigates the design and optimization of a wireless power transmission link targeting Micro-Ball Endoscopy applications. A novel asymmetric resonant coupling structure is proposed to deliver power to an endoscopic Micro-Ball system for image read-out after it is excreted. Such a technology enables many key medical applications with stringent requirements for small system volume and high power delivery efficiency. A prototyping power transmission sub-system of the Micro-Ball system was implemented. It consists of primary coil, middle resonant coil, and cube-like full-direction secondary receiving coils. Our experimental results proved that 200mW of power can be successfully delivered. Such a wireless power transmission capability could satisfy the requirements of the Micro-Ball based endoscopy application. The transmission efficiency is in the range of 41% (worst working condition) to 53% (best working condition). Comparing to conventional structures, Asymmetric Resonant Coupling Structure improves power efficiency by 13%.

Structure of Flame Balls at Low Lewis-Number (SOFBALL): Preliminary Results From the STS-83 and STS-94 Space Flight Experiments

NASA Technical Reports Server (NTRS)

Ronney, Paul D.; Wu, Ming-Shin; Pearlman, Howard G.; Weiland, Karen J.

1998-01-01

Results from the Structure Of Flame Balls At Low Lewis-number (SOFBALL) space flight experiment conducted on the MSL-1 Space Shuttle missions are reported. Several new insights were obtained, including: much lower buoyancy-induced drift speed than anticipated pre-flight; repulsion of adjacent flame balls due to their mutual interaction; remarkable sensitivity of flame balls to small accelerations resulting from Orbiter attitude control maneuvers; and very similar net heat release for all flame balls in all mixtures tested. Comparison of experimental results to computational predictions reveals limitations in current models of H2-02 chemistry for very lean mixtures. It is discussed how the results of these space experiments may provide an improved understanding of the interactions of the two most important phenomena in combusting materials, namely chemical reaction and transport processes, in the unequivocally simplest possible configuration.

Application of a Saddle-Type Eddy Current Sensor in Steel Ball Surface-Defect Inspection

PubMed Central

Zhong, Mingming; Xie, Fengqin; Cao, Maoyong

2017-01-01

Steel ball surface-defect inspection was performed by using a new saddle-type eddy current sensor (SECS), which included a saddle coil and a signal conditioning circuit. The saddle coil was directly wound on the steel ball’s outer bracket in a semi-circumferential direction. Driven by a friction wheel, the test steel ball rotated in a one-dimensional direction, such that the steel ball surface was fully scanned by the SECS. There were two purposes for using the SECS in the steel ball inspection system: one was to reduce the complexity of the unfolding wheel of the surface deployment mechanism, and the other was to reduce the difficulty of sensor processing and installation. Experiments were carried out on bearing steel balls in diameter of 8 mm with three types of representative and typical defects by using the SECS, and the results showed that the inspection system can detect surface defects as small as 0.05 mm in width and 0.1 mm in depth with high-repetition detection accuracy, and the detection efficiency of 5 pcs/s, which meet the requirement for inspecting ISO grade 10 bearing steel balls. The feasibility of detecting steel ball surface defects by SECS was verified. PMID:29206154

Insecticides evaluated as regulatory immersion treatments to eliminate third-instar Japanese beetles (Coleoptera: Scarabaeidae) from small-diameter field-grown nursery plants

USDA-ARS?s Scientific Manuscript database

Japanese beetles, Popillia japonica Newman, are a quarantine issue for nursery shipments to certain U.S. states. The Domestic Japanese Beetle Harmonization Plan (DJHP) allows balled and burlapped (B&B) root ball immersion in chlorpyrifos or bifenthrin for P. japonica certification. Study objective...

Reflections on a Disco Ball

ERIC Educational Resources Information Center

Ribeiro, Jair Lúcio Prados

2016-01-01

A disco ball is a spherical object covered with small plane mirrors. When light reflects on these mirrors, it is scattered in many directions, producing a novel effect. The mirror globe is usually set to rotate, creating a profusion of moving spots (Fig. 1). In this article, we present a geometrical description of the movement of these spots and…

Magnetically driven, acoustically tracked, translating-ball rheometer for small, opaque samples

NASA Astrophysics Data System (ADS)

Tran-Son-Tay, R.; Beaty, B. B.; Acker, D. N.; Hochmuth, R. M.

1988-08-01

A new rheometer has been designed to measure the rheological properties at low Reynolds number of microliter quantities of opaque suspensions. The rheometer uses a falling-ball technique to measure steady-state viscosity and a vertically oscillating, magnetically driven ball for viscoelastic measurements. The motion of the ball is tracked by ultrasound echo location, in which sound waves are transmitted and received by an ultrasound transducer mounted at the base of the tube. Concentrated suspensions of red blood cells are used as opaque test samples. The results obtained are in good agreement with those reported in the literature. The data confirm the fact that a concentrated suspension of red blood cells behaves as a shear thinning material and that the energy stored by the suspension during an oscillatory cycle increases with frequency. Testing of the rheometer is also made by using a Newtonian silicone oil. Viscosity measurements obtained with both the falling- and oscillating-ball methods are consistent and are within 2% of the value of 47.3±0.5 cP given by the Cannon-Fenske viscometer. However, it is found that the oscillating-ball technique gives the largest standard deviation, 6%, as opposed to 2% for the falling-ball technique.

Empirical links between instruction with teaching tools and the hierarchical model of intrinsic and extrinsic motivation in a Korean college tennis class.

PubMed

Shin, Myoungjin; Kwon, Sungho

2015-04-01

The objective of this study was to demonstrate the sequential process (i.e., social factors→mediators→motivation→consequences) underlying the Hierarchical Model of Intrinsic and Extrinsic Motivation at the contextual level in instruction using three teaching tools, modified balls, a high net, and colored balls and cones in a college-level tennis class in South Korea. 126 students enrolled in a 15-week tennis class participated in the study. The results indicate that the three teaching tools positively affected students' perceived competence, with perceived competence's beta on intrinsic motivation equal to 0.45. Intrinsic motivation was found to reduce negative affect further by -0.33, thereby demonstrating the sequential process of the Hierarchical Model of Intrinsic and Extrinsic Motivation.

Space Creation Dynamics in Basketball Small-Sided Games.

PubMed

Bredt, Sarah G T; Morales, Juan C P; Andrade, André G P; Torres, Juliana O; Peixoto, Gustavo H; Greco, Pablo J; Praça, Gibson M; Chagas, Mauro H

2018-02-01

Space creation dynamics (SCDs) describe actions players perform to create a scoring opportunity. This study compared SCDs and types of offense during three different three versus three (3vs.3) basketball small-sided games (SSGs) played in half court: 3vs.3 with man-to-man defense in half playing area (3vs.3 HALF ), 3vs.3 with man-to-man defense in full playing area (3vs.3 FULL ), and 3vs.3 with reduced shot clock (3vs.3 RT ). We also investigated the efficacy of SCDs in all SSGs and the reliability of SCDs in 3vs.3 HALF . While the efficacy of SCDs did not differ among these SSGs, 3vs.3 RT presented significantly more "space creation with ball dribbled" and "shot clock violations," and less "on ball screens." 3vs.3 FULL presented no differences in the SCDs and types of offense compared with 3vs.3 HALF . Reliability within 3vs.3 HALF was higher for "space creation with ball dribbled," "space creation without the ball," "set offenses," "fast breaks," and "loss of ball during passing or dribbling." We concluded that 3vs.3 basketball SSGs with different rules can be used for training different tactical behaviors important to formal games, especially since the 3vs.3 HALF presented good reliability for many variables related to tactical behavior.

Seed Balls and the Circle of Courage: A Decolonization Model of Youth Development in an Environmental Stewardship Program

ERIC Educational Resources Information Center

Wenger-Schulman, A. R. S.; Hoffman, Lauren

2018-01-01

Middle School 88 in Brooklyn, New York serves a community of students often considered at high risk for dropping out of high school and other socially undesirable behaviors. In this high-need setting, the authors designed and implemented an environmental education program designed to meet the needs of urban youth of color. The approach they used,…

History through Art and Architecture: The Art and Architecture of the Maya. Teacher's Manual [and] Creative Workbook.

ERIC Educational Resources Information Center

Campbell, Ann; Hoag, John, Ed.

This packet--a teacher's manual, student workbook, and color poster--was designed to accompany a 2-part videotape program. The teacher's manual provides a script of the videotape, and is organized in 2 sections. Part 1, "Kings, Glyphs, Temples and Ball Courts", looks at the written glyph language and the Solar and Ritual calendars of the…

A novel high-throughput imaging system for automated analyses of avoidance behavior in zebrafish larvae.

PubMed

Pelkowski, Sean D; Kapoor, Mrinal; Richendrfer, Holly A; Wang, Xingyue; Colwill, Ruth M; Creton, Robbert

2011-09-30

Early brain development can be influenced by numerous genetic and environmental factors, with long-lasting effects on brain function and behavior. The identification of these factors is facilitated by recent innovations in high-throughput screening. However, large-scale screening in whole organisms remains challenging, in particular when studying changes in brain function or behavior in vertebrate model systems. In this study, we present a novel imaging system for high-throughput analyses of behavior in zebrafish larvae. The three-camera system can image 12 multiwell plates simultaneously and is unique in its ability to provide local visual stimuli in the wells of a multiwell plate. The acquired images are converted into a series of coordinates, which characterize the location and orientation of the larvae. The developed imaging techniques were tested by measuring avoidance behaviors in seven-day-old zebrafish larvae. The system effectively quantified larval avoidance and revealed an increased edge preference in response to a blue or red 'bouncing ball' stimulus. Larvae also avoid a bouncing ball stimulus when it is counter-balanced with a stationary ball, but do not avoid blinking balls counter-balanced with a stationary ball. These results indicate that the seven-day-old larvae respond specifically to movement, rather than color, size, or local changes in light intensity. The imaging system and assays for measuring avoidance behavior may be used to screen for genetic and environmental factors that cause developmental brain disorders and for novel drugs that could prevent or treat these disorders. Copyright © 2011 Elsevier B.V. All rights reserved.

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.

Reply to remarks of R Cross on ‘A comparative study of two types of ball-on-ball collision’

NASA Astrophysics Data System (ADS)

White, Colin

2018-01-01

In this letter, I explain an error which was identified to me in my use of the equation v_n=e^nv0 in the first method of measuring the coefficient of restitution of two colliding Newton’s cradle balls. In fact, for this particular scenario, the correct equation is shown to be v_n=≤ft(\\frac{1+e}{2}\\right)n v0 . However, it is further shown that, in this case, the resulting error is small and the thesis of the paper remains valid.

Aids to Develop Throwing and Catching Skills.

ERIC Educational Resources Information Center

Schilling, Mary Lou, Ed.

1982-01-01

THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT: STICKER MITT: (Creative Concepts Unlimited, P.O. Box 176, Elmhurst, IL 60126) A plastic mitt with small suction cups on the palm of the glove so that a plastic ball will easily adhere to it. This ensures a successful experience for children who have never caught a ball!! Approximate cost: $8.95.…

78 FR 20371 - Small Business Size Standards; Waiver of the Nonmanufacturer Rule

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-04

... SMALL BUSINESS ADMINISTRATION Small Business Size Standards; Waiver of the Nonmanufacturer Rule AGENCY: U.S. Small Business Administration. ACTION: On April 16, 2001, SBA granted a Class Waiver of the Nonmanufacturer Rule (NMR) for Aerospace Ball and Roller Bearings, North American Industry Classification System...

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

Liu, Zhi-jie; Dai, Le-yang; Yang, De-zheng

Highlights: • A novel and high efficiency synthesizing AlN powders method combining mechanical ball milling and DBDP has been developed. • The particle size, the crystallite size, the lattice distortion, the morphology of Al{sub 2}O{sub 3} powders, and the AlN conversion rate are investigated and compared under the ball milled Al{sub 2}O{sub 3} powders with DBDP and without DBDP. • The ball milled Al{sub 2}O{sub 3} powders with DBDP have small spherical structure morphology with very fine particles size and high specific surface area, which result in a higher chemical efficiency and a higher AlN conversion rate at lower thermalmore » temperature. - Abstract: In this paper, aluminum nitride (AlN) powers have been produced with a novel and high efficiency method by thermal annealing at 1100–1600 °C of alumina (Al{sub 2}O{sub 3}) powders which were previously ball milled for various time up to 40 h with and without the assistant of dielectric barrier discharge plasma (DBDP). The ball milled Al{sub 2}O{sub 3} powders with DBDP and without DBDP and the corresponding synthesized AlN powers are characterized by X-ray diffraction, scanning electron microscope, and transmission electron microscopy. From the characteristics of the ball milled Al{sub 2}O{sub 3} powders with DBDP and without DBDP, it can be seen that the ball milled Al{sub 2}O{sub 3} powders with DBDP have small spherical structure morphology with very fine particles size and high specific surface area, which result in a higher chemical efficiency and a higher AlN conversion rate at lower thermal temperature. Meanwhile, the synthesized AlN powders can be known as hexagonal AlN with fine crystal morphology and irregular lump-like structure, and have uniform distribution with the average particle size of about between 500 nm and 1000 nm. This provides an important method for fabricating ultra fine powders and synthesizing nitrogen compounds.« less

Mechanochemical Ring-Opening Polymerization of Lactide: Liquid-Assisted Grinding for the Green Synthesis of Poly(lactic acid) with High Molecular Weight.

PubMed

Ohn, Nuri; Shin, Jihoon; Kim, Sung Sik; Kim, Jeung Gon

2017-09-22

Mechanochemical polymerization of lactide is carried out by using ball milling. Mechanical energy from collisions between the balls and the vessel efficiently promotes an organic-base-mediated metal- and solvent-free solid-state polymerization. Investigation of the parameters of the ball-milling synthesis revealed that the degree of lactide ring-opening polymerization could be modulated by the ball-milling time, vibration frequency, mass of the ball media, and liquid-assisted grinding. Liquid-assisted grinding was found to be an especially important factor for achieving a high degree of mechanochemical polymerization. Although polymer-chain scission from the strong collision energy prevented mechanical-force-driven high-molecular-weight polymer synthesis, the addition of only a small amount of liquid enabled sufficient energy dissipation and poly(lactic acid) was thereby obtained with a molecular weight of over 1×10 5  g mol -1 . © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Solid Lubricated Rolling Element Bearings

DTIC Science & Technology

1979-02-15

lubricant into uneven patches of varnish . This varnish , along with the file-like action of the exposed ball carbides on the relatively softer races, can...its structure. Fluorine , one of the most reactive elements, reacts with graphite without combustion from about 790’F to 1022°F, forming a grey-colored...to allow for molding and machining after molding. 0 Method 2 (Hughes) Impregnating these dense weaves with a Thermid 600 polyimide varnish

Development of a technique for contrast radiographic examination of the gastrointestinal tract in ball pythons (Python regius).

PubMed

Banzato, Tommaso; Russo, Elisa; Finotti, Luca; Zotti, Alessandro

2012-07-01

To develop a technique for radiographic evaluation of the gastrointestinal tract in ball pythons (Python regius). 10 ball python cadavers (5 males and 5 females) and 18 healthy adult ball pythons (10 males and 8 females). Live snakes were allocated to 3 groups (A, B, and C). A dose (25 mL/kg) of barium sulfate suspension at 3 concentrations (25%, 35%, and 45% [wt/vol]) was administered through an esophageal probe to snakes in groups A, B, and C, respectively. Each evaluation ended when all the contrast medium had reached the large intestine. Transit times through the esophagus, stomach, and small intestine were recorded. Imaging quality was evaluated by 3 investigators who assigned a grading score on the basis of predetermined criteria. Statistical analysis was conducted to evaluate differences in quality among the study groups. The esophagus and stomach had a consistent distribution pattern of contrast medium, whereas 3 distribution patterns of contrast medium were identified in the small intestine, regardless of barium concentration. Significant differences in imaging quality were detected among the 3 groups. Radiographic procedures were tolerated well by all snakes. The 35% concentration of contrast medium yielded the best imaging quality. Use of contrast medium for evaluation of the cranial portion of the gastrointestinal tract could be a reliable technique for the diagnosis of gastrointestinal diseases in ball pythons. However, results of this study may not translate to other snake species because of variables identified in this group of snakes.

To Believe the Past or to Trust the Future

ERIC Educational Resources Information Center

Jin, Fengtao; Zhou, Zhaoyan

2012-01-01

A small ball rolls down from a quarter-circle to a frictionless plane. What will be the magnitude of the normal force when the ball arrives at the tangent point of the circle and the plane? According to the centripetal force formula, the normal force will be 3 "mg" when the curvature radius of the circle is considered, but will be "mg" instead…

[Volleyball sport school injuries].

PubMed

Knobloch, K; Rossner, D; Gössling, T; Richter, M; Krettek, C

2004-12-01

Ball sport school injuries account for a significant morbidity among children and adolescents. Volleyball is popular in school sport and leads frequent injuries in youth besides basketball and soccer. During a school year 2234 school sport injuries have been reported to the Gemeinde Unfall Versicherung (GUV) from all schools in Niedersachsen, Germany. The major disciplines were ball sport injuries, accounting for 59.5 % (1330 accidents), Gymnastic sport injuries follow at second position accounting for 18 % (403 accidents), followed by athletics with 8.1 %. Regarding the non-gender-specific distribution of the ball sport disciplines, basketball leads with 32.4 % (431 injuries), followed by soccer (23.8 %, 316 injuries), volleyball (17.4 %, 232 injuries), small ball games (11.2 %, 149 injuries), handball (8.3 %, 110 injuries), and hockey (4.9 %, 65 injuries). In boys, volleyball accounts third among the ball sport injuries (10 %, 63 injuries), after soccer (38 %, 245 injuries), and basketball (28.5 %, 185 injuries). In girls, volleyball was the second major ball sport injury discipline (24.8 %, 169 injuries) after basketball (36.1 %, 246 injuries), followed by small ball games (12.9 %, 88 injuries), and soccer at 4 (th) position (10.4 %, 71 injuries). The analysis of the distribution of injury during volleyball accidents dominate upper extremity injuries (71.3 %), with special emphasis on finger injuries in 53 %, followed by lower extremity injuries (21.5 %) and head injuries (4.3 %). Spine injuries were rare (0.9 %). The type of injury during volleyball school sport injuries were predominantly sprains (21 %), ligament distorsions and ruptures (20 %), fractures (17 %), and bruise (16 %). Analyzing the circumstances of the injuries, most injuries during volleyball school sport occurred without a opponent contact during ball contact (59 %), followed during movements (9 %), the landing phase (9 %), and after a strike of the ball (7 %). Volleyball injuries account for a significant number of all school sport related injuries. Upper extremity injuries account for the vast majority of all injuries especially during individual game play. Blunt trauma and fractures are most prevalent among school sport injuries in soccer. Preventive measures such as preservation of a high level of attention when scheduling a sport lesson, safety measures, and awareness of the possible severe injuries and knowledge in basic life support are mandatory to implement in school sports, since ball sport is proven to be very valuable for the physical and psychological development of the children. The role of preventive finger taping in volleyball school sport has to be evaluated in prospective clininal trials.

Benefit from NASA

NASA Image and Video Library

1998-01-01

The Ultra 500 Series golf balls, introduced in 1995 by Wilson Sporting Goods Company, has 500 dimples arranged in a pattern of 60 spherical triangles. The design employs NASA's aerodynamics technology analysis of air loads of the tank and Shuttle orbiter that was performed under the Space Shuttle External Tank program. According to Wilson, this technology provides "the most symmetrical ball surface available, sustaining initial velocity longer and producing the most stable ball flight for unmatched accuracy and distance." The dimples are in three sizes, shapes and depths mathematically positioned for the best effect. The selection of dimples and their placement optimizes the interaction of opposing forces of lift and drag. Large dimples reduce air drag, enhance lift, and maintain spin for distance. Small dimples prevent excessive lift that destabilizes the ball flight and the medium size dimples blend the other two.

16 CFR 1117.3 - Reportable information.

Code of Federal Regulations, 2011 CFR

2011-01-01

... balloon, or on a marble, small ball, latex balloon or other small part contained in a toy or game and, as a result of that incident the child died, suffered serious injury, ceased breathing for any length...

16 CFR 1117.3 - Reportable information.

Code of Federal Regulations, 2014 CFR

2014-01-01

... balloon, or on a marble, small ball, latex balloon or other small part contained in a toy or game and, as a result of that incident the child died, suffered serious injury, ceased breathing for any length...

16 CFR 1117.3 - Reportable information.

Code of Federal Regulations, 2012 CFR

2012-01-01

... balloon, or on a marble, small ball, latex balloon or other small part contained in a toy or game and, as a result of that incident the child died, suffered serious injury, ceased breathing for any length...

16 CFR 1117.3 - Reportable information.

Code of Federal Regulations, 2010 CFR

2010-01-01

... balloon, or on a marble, small ball, latex balloon or other small part contained in a toy or game and, as a result of that incident the child died, suffered serious injury, ceased breathing for any length...

Hemodynamic consequences of cardiac malformations in two juvenile ball pythons (Python regius).

PubMed

Jensen, Bjarke; Wang, Tobias

2009-12-01

Two cases of bifid ventricles and cardiac malformations in juvenile ball python (Python regius) were investigated by blood pressure measurements and macro- and microscopic sectioning. A study of a normal ball python was included for reference. In both cases, all cardiac chambers were enlarged and abnormally shaped. Internal assessment of the ventricles revealed a pronounced defect of the muscular ridge, which normally is responsible for separating the systemic and pulmonary circuits. Consistent with the small muscular ridge, systolic pressures were identical in the pulmonary and systemic arteries, but, the snakes, nevertheless, lived to reach body weights severalfold of their hatchling weight.

Nanometer-scale features in dolomite from Pennsylvanian rocks, Paradox Basin, Utah

NASA Astrophysics Data System (ADS)

Gournay, Jonas P.; Kirkland, Brenda L.; Folk, Robert L.; Lynch, F. Leo

1999-07-01

Scanning electron microscopy reveals an association between early dolomite in the Pennsylvanian Desert Creek (Paradox Fm.) and small (approximately 0.1 μm) nanometer-scale textures, termed `nannobacteria'. Three diagenetically distinct dolomites are present: early dolomite, limpid dolomite, and baroque dolomite. In this study, only the early dolomite contained nanometer-scale features. These textures occur as discrete balls and rods, clumps of balls, and chains of balls. Precipitation experiments demonstrate that these textures may be the result of precipitation in an organic-rich micro-environment. The presence of these nanometer-scale textures in Pennsylvanian rocks suggests that these early dolomites precipitated in organic-rich, bacterial environments.

Electromechanically Actuated Valve for Controlling Flow Rate

NASA Technical Reports Server (NTRS)

Patterson, Paul

2007-01-01

A proposed valve for controlling the rate of flow of a fluid would include an electric-motor-driven ball-screw mechanism for adjusting the seating element of the valve to any position between fully closed and fully open. The motor would be of a type that can be electronically controlled to rotate to a specified angular position and to rotate at a specified rate, and the ball screw would enable accurate linear positioning of the seating element as a function of angular position of the motor. Hence, the proposed valve would enable fine electronic control of the rate of flow and the rate of change of flow. The uniqueness of this valve lies in a high degree of integration of the actuation mechanism with the flow-control components into a single, relatively compact unit. A notable feature of this integration is that in addition to being a major part of the actuation mechanism, the ball screw would also be a flow-control component: the ball screw would be hollow so as to contain part of the main flow passage, and one end of the ball screw would be the main seating valve element. The relationships among the components of the valve are best understood by reference to the figure, which presents meridional cross sections of the valve in the fully closed and fully open positions. The motor would be supported by a bracket bolted to the valve body. By means of gears or pulleys and a timing belt, motor drive would be transmitted to a sleeve that would rotate on bearings in the valve body. A ball nut inside the sleeve would be made to rotate with the sleeve by use of a key. The ball screw would pass through and engage the ball nut. A key would prevent rotation of the ball screw in the valve body while allowing the ball screw to translate axially when driven by the ball nut. The outer surface of the ball screw would be threaded only in a mid-length region: the end regions of the outer surface of the ball screw would be polished so that they could act as dynamic sealing surfaces. The inlet end (the right end as depicted in the figure) of the ball screw would be the main seating valve element: in the fully closed position, it would be pressed against the valve seat, as depicted in the upper part of the figure. A retainer would hold the valve seat in an inlet fitting. In addition, the retainer would be contoured to obtain a specified flow rate as a function of axial position of the ball screw. In the fully closed position, little force would be needed to press the ball screw against the seat because the push bore area upon which the upstream pressure would act would be small. The motor would position and hold the ball screw against the seat, providing the force necessary for sealing. To open the valve to a particular position, the motor would be commanded to rotate to a particular angular position (equivalently, a particular number of revolutions) at a particular rate of rotation within its torque limitations. Once the valve was open, fluid would flow through the inlet fitting and the chamber in the inlet housing, past the seat and its retainer, along the hollow core of the ball screw, and through the outlet housing and outlet fitting. The net force generated from fluid pressure in the open position would be small because the pressure exposed to the push bore areas at the inlet and outlet are nearly equal and the forces generated would be in opposing directions.

A Small Business Management Entrepreneurship Curriculum: A Dual Progression Experience.

ERIC Educational Resources Information Center

Kuratko, Donald; LaFollette, William R.

1986-01-01

Describes Ball State University's "dual progression" curriculum for the small business management program. The program seeks to combine the best elements of entrepreneurial theory with the difficult facets of practical experience. The five major component courses (small business ventures, entrepreneurship, management information systems,…

16 CFR § 1117.3 - Reportable information.

Code of Federal Regulations, 2013 CFR

2013-01-01

... balloon, or on a marble, small ball, latex balloon or other small part contained in a toy or game and, as a result of that incident the child died, suffered serious injury, ceased breathing for any length...

Planetwide Color Movie

NASA Technical Reports Server (NTRS)

2000-01-01

The first color movie of Jupiter from NASA's Cassini spacecraft shows what it would look like to peel the entire globe of Jupiter, stretch it out on a wall into the form of a rectangular map, and watch its atmosphere evolve with time.

The brief movie clip spans 24 Jupiter rotations between Oct. 31 and Nov. 9, 2000.

Various patterns of motion are apparent all across Jupiter at the cloudtop level seen here. The Great Red Spot shows its counterclockwise rotation, and the uneven distribution of its high haze is obvious. To the east (right) of the Red Spot, oval storms, like ball bearings, roll over and pass each other. Horizontal bands adjacent to each other move at different rates. Strings of small storms rotate around northern-hemisphere ovals. The large grayish-blue 'hot spots' at the northern edge of the white Equatorial Zone change over the course of time as they march eastward across the planet. Ovals in the north rotate counter to those in the south. Small, very bright features appear quickly and randomly in turbulent regions, candidates for lightning storms.

The clip consists of 14 unevenly spaced timesteps, each a true color cylindrical projection of the complete circumference of Jupiter, from 60 degrees south to 60 degrees north. The maps are made by first assembling mosaics of six images taken by Cassini's narrow-angle camera in the same spectral filter over the course of one Jupiter rotation and, consequently, covering the whole planet. Three such global maps -- in red, green and blue filters -- are combined to make one color map showing Jupiter during one Jovian rotation. Fourteen such maps, spanning 24 Jovian rotations at uneven time intervals comprise the movie. The maps were reduced in scale by a factor of two to make them accessible on the Internet at reasonable rates. Occasional appearances of Io, Europa, and their shadows have not been removed.

The smallest visible features at the equator are about 600 kilometers (about 370 miles) across. In a map of this nature, the most extreme northern and southern latitudes are unnaturally stretched out.

Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

Stereo matching image processing by synthesized color and the characteristic area by the synthesized color

NASA Astrophysics Data System (ADS)

Akiyama, Akira; Mutoh, Eiichiro; Kumagai, Hideo

2014-09-01

We have developed the stereo matching image processing by synthesized color and the corresponding area by the synthesized color for ranging the object and image recognition. The typical images from a pair of the stereo imagers may have some image disagreement each other due to the size change, missed place, appearance change and deformation of characteristic area. We constructed the synthesized color and corresponding color area with the same synthesized color to make the distinct stereo matching. We constructed the synthesized color and corresponding color area with the same synthesized color by the 3 steps. The first step is making binary edge image by differentiating the focused image from each imager and verifying that differentiated image has normal density of frequency distribution to find the threshold level of binary procedure. We used Daubechies wavelet transformation for the procedures of differentiating in this study. The second step is deriving the synthesized color by averaging color brightness between binary edge points with respect to horizontal direction and vertical direction alternatively. The averaging color procedure was done many times until the fluctuation of averaged color become negligible with respect to 256 levels in brightness. The third step is extracting area with same synthesized color by collecting the pixel of same synthesized color and grouping these pixel points by 4 directional connectivity relations. The matching areas for the stereo matching are determined by using synthesized color areas. The matching point is the center of gravity of each synthesized color area. The parallax between a pair of images is derived by the center of gravity of synthesized color area easily. The experiment of this stereo matching was done for the object of the soccer ball toy. From this experiment we showed that stereo matching by the synthesized color technique are simple and effective.

Removable Type Expansion Bolt Innovative Design

NASA Astrophysics Data System (ADS)

Wang, Feng-Lan; Zhang, Bo; Gao, Bo; Liu, Yan-Xin; Gao, Bo

2016-05-01

Expansion bolt is a kind of the most common things in our daily life. Currently, there are many kinds of expansion bolts in the market. However, they have some shortcomings that mainly contain underuse and unremovement but our innovation of design makes up for these shortcomings very well. Principle of working follows this: expansion tube is fixed outside of bolt, steel balls and expansion covers are fixed inside. Meanwhile, the steel balls have 120° with each other. When using it ,expansion cover is moved in the direction of its internal part. So the front part of expansion bolt cover is increasingly becoming big and steel halls is moved outside. Only in this way can it be fixed that steel balls make expansion tube expand. When removing them, expansion bolt is moved outside. So the front part of expansion bolt cover is gradually becoming small and steel balls moves inside, after expansion tube shrinks, we can detach them.

The differences in analysing strategy of viscosity experiment between freshmen and laboratory assistant

NASA Astrophysics Data System (ADS)

Anggrayni, S.; Mubarok, H.; Putri, N. P.; Suprapto, N.; Kholiq, A.

2018-03-01

The viscosity is defined by dimension of a fluid that resists the force tending to motive the fluid to flow. The aim of viscosity experiment is to determine the fluid viscosity coefficient value. By using graphical analysis, the result of oil viscosity coefficient value which performed by laboratory assistant showed: (1) 0.20 Pa.s using solid ball with accuracy 99.64% and (2) 0.21 Pa.s using smaller solid ball with accuracy 99.17%. Meanwhile, the result of oil viscosity coefficient value which performed by freshmen showed: (1) 0.44 Pa.s using solid ball with accuracy 87.85% and (2) 0.32 Pa.s using smaller solid ball with accuracy 89.84%. The differences result of the freshmen and assistant laboratory viscosity experiment are caused by the freshmen calculated the coefficient viscosity value without velocity correction factor and they used small range fluid so the times are not identified well.

Using a Force Plate to Correct Student Misconceptions

NASA Astrophysics Data System (ADS)

Wyrembeck, Edward P.

2005-09-01

Each year during the unit on collisions I ask my physics students this conceptual question: If you want to close a door but you have too much inertia at the moment to get up and do it yourself, should you throw a ball that rebounds well, like a basketball, or a ball that rebounds poorly, like a ball of modeling dough, at the door? I also impose the condition that the two balls must have the same momenta when they strike the door. I give my students some time to discuss the problem in small groups and then make a prediction. I find that most students predict incorrectly that the dough ball will be more effective at closing the door because it is solid throughout and denser than the hollow, air-filled basketball. The students do not focus on the better-rebounding basketball and the greater change in velocity that it experiences than the modeling dough ball when they strike a solid object like a door. To correct this misconception I use a Vernier2 force plate to measure the impulse of a size 3 basketball and a ball of modeling dough of equal mass (0.3213 ± 0.0002 kg) dropped from the same height of 0.200 ± 0.002 m, to ensure equal velocities, onto the force plate. While I realize that a collision between a ball and a force plate is not exactly the same as a collision between a ball and a door, a more complex system, I believe it offers some very useful insights into the problem. I also include in this paper an extension on validating the impulse-momentum theorem.

Symmetry breaking in (gravitating) scalar field models describing interacting boson stars and Q-balls

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

Brihaye, Yves; Caebergs, Thierry; Hartmann, Betti

2009-09-15

We investigate the properties of interacting Q-balls and boson stars that sit on top of each other in great detail. The model that describes these solutions is essentially a (gravitating) two-scalar field model where both scalar fields are complex. We construct interacting Q-balls or boson stars with arbitrarily small charges but finite mass. We observe that in the interacting case--where the interaction can be either due to the potential or due to gravity--two types of solutions exist for equal frequencies: one for which the two-scalar fields are equal, but also one for which the two-scalar fields differ. This constitutes amore » symmetry breaking in the model. While for Q-balls asymmetric solutions have always corresponding symmetric solutions and are thus likely unstable to decay to symmetric solutions with lower energy, there exists a parameter regime for interacting boson stars, where only asymmetric solutions exist. We present the domain of existence for two interacting nonrotating solutions as well as for solutions describing the interaction between rotating and nonrotating Q-balls and boson stars, respectively.« less

A simple demonstration when studying the equivalence principle

NASA Astrophysics Data System (ADS)

Mayer, Valery; Varaksina, Ekaterina

2016-06-01

The paper proposes a lecture experiment that can be demonstrated when studying the equivalence principle formulated by Albert Einstein. The demonstration consists of creating stroboscopic photographs of a ball moving along a parabola in Earth's gravitational field. In the first experiment, a camera is stationary relative to Earth's surface. In the second, the camera falls freely downwards with the ball, allowing students to see that the ball moves uniformly and rectilinearly relative to the frame of reference of the freely falling camera. The equivalence principle explains this result, as it is always possible to propose an inertial frame of reference for a small region of a gravitational field, where space-time effects of curvature are negligible.

Disruptive Commercial Technologies

DTIC Science & Technology

2008-06-26

with rotating mirrored “ disco ” balls could be used to blind and confuse Marine forces while masking Red positions. COTS polycarbonate first-responder...specialize in small orders” • Active/passive − Magnesium firebreak − Smoke bombs − 2M candlepower IR illuminators aimed at disco balls − IR strobes...and virtual exercises, we must also equip our irregular OPFOR with the tools they would be likely to acquire and apply against us in creative new ways

Effect of low-temperature degradation on the mechanical and microstructural properties of tooth-colored 3Y-TZP ceramics.

PubMed

Nakamura, K; Harada, A; Ono, M; Shibasaki, H; Kanno, T; Niwano, Y; Adolfsson, E; Milleding, P; Örtengren, U

2016-01-01

The aim of the present study was to evaluate the effects of low-temperature degradation (LTD) induced by autoclaving on the mechanical and microstructural properties of tooth-colored 3 mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP). In total, 162 disc-shaped 3Y-TZP specimens were prepared. Two-thirds of the specimens were shaded by either the infiltration or powder mixing methods while the remaining specimens were used without coloring. The specimens were autoclaved at 134 °C for 0, 10, and 100 h to induce LTD (n=18 for each group). Chemical compositions were analyzed with X-ray fluorescence spectroscopy. Biaxial flexural strength was measured using a piston-on-three-ball test. The surface fraction and penetration depth of the monoclinic phase were examined using X-ray diffraction and scanning electron microscopy, respectively. The tooth-colored 3Y-TZP specimens contained Fe2O3 and Er2O3 (infiltration technique), and Fe2O3 (powder mixing method) at concentrations of<0.5 wt%. The tooth-colored 3Y-TZP had higher strength than the non-colored material after 100 h of autoclaving. In terms of surface fraction and penetration depth, the generation of monoclinic phase was significantly lower in the tooth-colored 3Y-TZP than in the non-colored material. The tooth-colored 3Y-TZP possessed equivalent biaxial flexural strength to that of the non-colored material and higher resistance to LTD regardless of the coloring technique (infiltration technique or powder mixing method) when the coloring pigments were contained at concentrations used in the present study. Copyright © 2015 Elsevier Ltd. All rights reserved.

FOD impact testing of composite fan blades

NASA Technical Reports Server (NTRS)

Johns, R. H.

1974-01-01

The results of impact tests on large, fiber composite fan blades for aircraft turbofan engine applications are discussed. Solid composite blades of two different sizes and designs were tested. Both graphite/epoxy and boron/epoxy were evaluated. In addition, a spar-shell blade design was tested that had a boron/epoxy shell bonded to a titanium spar. All blades were tested one at a time in a rotating arm rig to simulate engine operating conditions. Impacting media included small gravel, two inch diameter ice balls, gelatin and RTV foam-simulated birds, as well as starlings and pigeons. The results showed little difference in performance between the graphite and boron/epoxy blades. The results also indicate that composite blades may be able to tolerate ice ball and small bird impacts but need improvement to tolerate birds in the small duck and larger category.

FOD impact testing of composite fan blades

NASA Technical Reports Server (NTRS)

Johns, R. H.

1974-01-01

The results of impact tests on large, fiber composite fan blades for aircraft turbofan engine applications are discussed. Solid composite blades of two different sizes and designs were tested. Both graphite/epoxy and boron/epoxy were evaluated. In addition, a spar-shell blade design was tested that had a boron/epoxy shell bonded to a titanium spar. All blades were tested one at a time in a rotating arm rig to simulate engine operating conditions. Impacting media included small gravel, two inch diameter ice balls, gelatin, and RTV foam-simulated birds, as well as starlings and pigeons. The results showed little difference in performance between the graphite and boron/epoxy blades. The results also indicate that composite blades may be able to tolerate ice ball and small bird impacts but need improvement to tolerate birds in the small duck and larger category.

Impact testing on composite fan blades

NASA Technical Reports Server (NTRS)

Johns, R. H.

1974-01-01

The results of impact tests on large, fiber composite fan blades for aircraft turbofan engine applications are discussed. Solid composite blades of two different sizes and designs were tested. Both graphite/epoxy and boron/epoxy were evaluated. In addition, a spar-shell blade design was tested that had a boron/epoxy shell bonded to a titanium spar. All blades were tested one at a time in a rotating arm rig to simulate engine operating conditions. Impacting media included small gravel, two inch diameter ice balls, gelatin and RTV foam-simulated birds, as well as starlings and pigeons. The results showed little difference in performance between the graphite and boron/epoxy blades. The results also indicate that composite blades may be able to tolerate ice ball and small bird impacts but need improvement to tolerate birds in the small duck and larger category.

Effect of the racket mass and the rate of strokes on kinematics and kinetics in the table tennis topspin backhand.

PubMed

Iino, Yoichi; Kojima, Takeji

2016-01-01

The purpose of this study was to investigate the effect of the racket mass and the rate of strokes on the kinematics and kinetics of the trunk and the racket arm in the table tennis topspin backhand. Eight male Division I collegiate table tennis players hit topspin backhands against topspin balls projected at 75 balls · min(-1) and 35 balls · min(-1) using three rackets varying in mass of 153.5, 176 and 201.5 g. A motion capture system was used to obtain trunk and racket arm motion data. The joint torques of the racket arm were determined using inverse dynamics. The racket mass did not significantly affect all the trunk and racket arm kinematics and kinetics examined except for the wrist dorsiflexion torque, which was significantly larger for the large mass racket than for the small mass racket. The racket speed at impact was significantly lower for the high ball frequency than for the low ball frequency. This was probably because pelvis and upper trunk axial rotations tended to be more restricted for the high ball frequency. The result highlights one of the advantages of playing close to the table and making the rally speed fast.

Effect of upper body plyometric training on physical performance in healthy individuals: A systematic review.

PubMed

Singla, Deepika; Hussain, M Ejaz; Moiz, Jamal Ali

2018-01-01

To determine the impact of upper body plyometric training (UBPT) on physical performance parameters such as strength, ball throwing speed, ball throw distance and power in healthy individuals. PubMed, Scopus, ResearchGate and ERIC databases were searched up to August 2017. Selection of articles was done if they described the outcomes of an upper body plyometric exercise intervention; included measures of strength, ball throwing speed, ball throw distance, or power; included healthy individuals; used a randomized control trial; and had full text available in English language. The exclusion criteria were unpublished research work and clubbing of UBPT with some other type(s) of training apart from routine sports training. PEDro scale was used to rate the quality of studies eligible for this review. Initially 264 records were identified and out of them only 11 articles met the eligibility criteria and were selected (PEDro score = 4 to 6). Though large to very small effects observed in improving ball throwing velocity, ball throwing distance, power and strength of upper limb muscles after UBPT, the results should be implemented with caution. Inconclusive results obtained preclude any strong conclusion regarding the efficacy of UBPT on physical performance in healthy individuals. Copyright © 2017 Elsevier Ltd. All rights reserved.

78 FR 59624 - Guidance for Industry #223: Small Entity Compliance Guide-Declaring Color Additives in Animal...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-27

... industry 223 entitled ``Small Entity Compliance Guide--Declaring Color Additives in Animal Foods.'' This... of certified color additives on the labels of animal food including animal feeds and pet foods. DATES... SECG entitled ``Small Entity Compliance Guide--Declaring Color Additives in Animal Foods.'' This SECG...

On-machine precision preparation and dressing of ball-headed diamond wheel for the grinding of fused silica

NASA Astrophysics Data System (ADS)

Chen, Mingjun; Li, Ziang; Yu, Bo; Peng, Hui; Fang, Zhen

2013-09-01

In the grinding of high quality fused silica parts with complex surface or structure using ball-headed metal bonded diamond wheel with small diameter, the existing dressing methods are not suitable to dress the ball-headed diamond wheel precisely due to that they are either on-line in process dressing which may causes collision problem or without consideration for the effects of the tool setting error and electrode wear. An on-machine precision preparation and dressing method is proposed for ball-headed diamond wheel based on electrical discharge machining. By using this method the cylindrical diamond wheel with small diameter is manufactured to hemispherical-headed form. The obtained ball-headed diamond wheel is dressed after several grinding passes to recover geometrical accuracy and sharpness which is lost due to the wheel wear. A tool setting method based on high precision optical system is presented to reduce the wheel center setting error and dimension error. The effect of electrode tool wear is investigated by electrical dressing experiments, and the electrode tool wear compensation model is established based on the experimental results which show that the value of wear ratio coefficient K' tends to be constant with the increasing of the feed length of electrode and the mean value of K' is 0.156. Grinding experiments of fused silica are carried out on a test bench to evaluate the performance of the preparation and dressing method. The experimental results show that the surface roughness of the finished workpiece is 0.03 μm. The effect of the grinding parameter and dressing frequency on the surface roughness is investigated based on the measurement results of the surface roughness. This research provides an on-machine preparation and dressing method for ball-headed metal bonded diamond wheel used in the grinding of fused silica, which provides a solution to the tool setting method and the effect of electrode tool wear.

Scale-up of organic reactions in ball mills: process intensification with regard to energy efficiency and economy of scale.

PubMed

Stolle, Achim; Schmidt, Robert; Jacob, Katharina

2014-01-01

The scale-up of the Knoevenagel-condensation between vanillin and barbituric acid carried out in planetary ball mills is investigated from an engineering perspective. Generally, the reaction proceeded in the solid state without intermediate melting and afforded selectively only one product. The reaction has been used as a model to analyze the influence and relationship of different parameters related to operation in planetary ball mills. From the viewpoint of technological parameters the milling ball diameter, dMB, the filling degree with respect to the milling balls' packing, ΦMB,packing, and the filling degree of the substrates with respect to the void volume of the milling balls' packing, ΦGS, have been investigated at different reaction scales. It was found that milling balls with small dMB lead to higher yields within shorter reaction time, treaction, or lower rotation frequency, rpm. Thus, the lower limit is set considering the technology which is available for the separation of the milling balls from the product after the reaction. Regarding ΦMB,packing, results indicate that the optimal value is roughly 50% of the total milling beakers' volume, VB,total, independent of the reaction scale or reaction conditions. Thus, 30% of VB,total are taken by the milling balls. Increase of the initial batch sizes changes ΦGS significantly. However, within the investigated parameter range no negative influence on the yield was observed. Up to 50% of VB,total can be taken over by the substrates in addition to 30% for the total milling ball volume. Scale-up factors of 15 and 11 were realized considering the amount of substrates and the reactor volume, respectively. Beside technological parameters, variables which influence the process itself, treaction and rpm, were investigated also. Variation of those allowed to fine-tune the reaction conditions in order to maximize the yield and minimize the energy intensity.

Novel technology to prepare oral formulations for preclinical safety studies.

PubMed

Niwa, Toshiyuki; Hashimoto, Naofumi

2008-02-28

A novel method to prepare oral formulations, normally suspended dosage form, for preclinical safety studies in animals has been developed using a rotation/revolution mixer. Small hard balls made of zirconia were added to the mixing process to evaluate effectiveness in making a high quality suspension. The driving with balls loaded in the cylindrical container (vessel) of the mixer was quite efficient in dispersing and milling the particles of the active pharmaceutical ingredient (API) in an aqueous medium. The API powder and a small amount of oral aqueous medium (vehicle) were successfully mixed by the spinning motion of the balls in the vessel as though the paste-like suspension was kneaded with a mortar and pestle. It was found that the milled suspension with the mean size of 10-20microm could be prepared, in addition finer milling of less than 10microm could be achieved by selecting the material of vessel. Optimum driving conditions including mixing time, size and quantity of balls, and the standard operational procedure was established using compounds varying in physicochemical properties. The particle size and quantitative analysis by HPLC showed that the resultant suspension was well-milled and highly homogeneous with the nearly intended concentration of API. The proposed method established by this experiment could be applied to the actual safety studies in the real preparation scale of oral suspension.

Measurement of Direct Current Voltage Causing Electrical Pitting

NASA Astrophysics Data System (ADS)

Noguchi, Shoji; Kakinuma, Shin-Nosuke; Kanada, Tohru

It is widely known that electrical pitting occurs when an electrical current is passed through a ball or roller bearing. The authors have investigated critical electrical current density causing electrical pitting and have shown that it occurs in a ball bearing even at an extremely low current. In this paper we present the results of an experiment in which a small ball bearing was supplied with a direct current (DC) voltage to determine the voltage required to induce a current. A film of grease acts as the insulator on an antifriction bearing used, and the thickness of this film is an important consideration and the current must pass through this film. Four types of grease were used on the bearing, which was rotated at various speed during 500 hours. A potential of 1.3V to 1.5V was necessary to induce the flow of current. The results indicate that the voltage supplied by typical dry cell batteries is sufficient to drive a currents through a small bearing, and that the experimental conditions had little effect on the magnitude of the flowing current.

Coordinate measuring machine test standard apparatus and method

DOEpatents

Bieg, L.F.

1994-08-30

A coordinate measuring machine test standard apparatus and method are disclosed which includes a rotary spindle having an upper phase plate and an axis of rotation, a kinematic ball mount attached to the phase plate concentric with the axis of rotation of the phase plate, a groove mounted at the circumference of the phase plate, and an arm assembly which rests in the groove. The arm assembly has a small sphere at one end and a large sphere at the other end. The small sphere may be a coordinate measuring machine probe tip and may have variable diameters. The large sphere is secured in the kinematic ball mount and the arm is held in the groove. The kinematic ball mount includes at least three mounting spheres and the groove is an angular locating groove including at least two locking spheres. The arm may have a hollow inner core and an outer layer. The rotary spindle may be a ratio reducer. The device is used to evaluate the measuring performance of a coordinate measuring machine for periodic recertification, including 2 and 3 dimensional accuracy, squareness, straightness, and angular accuracy. 5 figs.

Coordinate measuring machine test standard apparatus and method

DOEpatents

Bieg, Lothar F.

1994-08-30

A coordinate measuring machine test standard apparatus and method which iudes a rotary spindle having an upper phase plate and an axis of rotation, a kinematic ball mount attached to the phase plate concentric with the axis of rotation of the phase plate, a groove mounted at the circumference of the phase plate, and an arm assembly which rests in the groove. The arm assembly has a small sphere at one end and a large sphere at the other end. The small sphere may be a coordinate measuring machine probe tip and may have variable diameters. The large sphere is secured in the kinematic ball mount and the arm is held in the groove. The kinematic ball mount includes at least three mounting spheres and the groove is an angular locating groove including at least two locking spheres. The arm may have a hollow inner core and an outer layer. The rotary spindle may be a ratio reducer. The device is used to evaluate the measuring performance of a coordinate measuring machine for periodic recertification, including 2 and 3 dimensional accuracy, squareness, straightness, and angular accuracy.

Effect of the number of ball contacts within bouts of 4 vs. 4 small-sided soccer games.

PubMed

Dellal, Alexandre; Lago-Penas, Carlos; Wong, Del P; Chamari, Karim

2011-09-01

The aim of this study was to examine the influence of the number of ball touches authorized per possession on the physical demands, technical performances and physiological responses throughout the bouts within 4 vs. 4 soccer small-sided games (SSGs). Twenty international soccer players (27.4 ± 1.5 y, 180.6 ± 2.3 cm, 79.2 ± 4.2 kg, body fat 12.7 ± 1.2%) performed three different 4 vs. 4 SSGs (4 × 4 min) in which the number of ball touches authorized per possession was manipulated (1 touch = 1T; 2 touches = 2T; Free Play = FP). The SSGs were divided in 4 bouts (B1, B2, B3 and B4) separated by 3 min of passive recovery. The physical performances, technical activities, heart rate responses, blood lactate and RPE were analyzed. The FP rule presented greater number of duels, induced the lowest decreases of the sprint and high-intensity performances, and affected less the technical actions (successful passes and number of ball losses) from B1 to B4 as compared with 1T and 2T forms. Moreover, the SSG played in 1T form led to reach higher solicitation of the high-intensity actions while players presented more difficulty to perform a correct technical action. The modification of the number of ball touches authorized per possession affects the soccer player activity from the first to the last bout of SSG, indicating that the determination of this rule has to be precisely planned by the coach according to the objectives of the training.

Miniature ball-tip optical fibers for use in thulium fiber laser ablation of kidney stones

NASA Astrophysics Data System (ADS)

Wilson, Christopher R.; Hardy, Luke A.; Kennedy, Joshua D.; Irby, Pierce B.; Fried, Nathaniel M.

2016-01-01

Optical fibers, consisting of 240-μm-core trunk fibers with rounded, 450-μm-diameter ball tips, are currently used during Holmium:YAG laser lithotripsy to reduce mechanical damage to the inner lining of the ureteroscope working channel during fiber insertion and prolong ureteroscope lifetime. Similarly, this study tests a smaller, 100-μm-core fiber with 300-μm-diameter ball tip during thulium fiber laser (TFL) lithotripsy. TFL was operated at a wavelength of 1908 nm, with 35-mJ pulse energy, 500-μs pulse duration, and 300-Hz pulse rate. Calcium oxalate/phosphate stone samples were weighed, laser procedure times were measured, and ablation rates were calculated for ball tip fibers, with comparison to bare tip fibers. Photographs of ball tips were taken before and after each procedure to track ball tip degradation and determine number of procedures completed before need for replacement. A high speed camera also recorded the cavitation bubble dynamics during TFL lithotripsy. Additionally, saline irrigation rates and ureteroscope deflection were measured with and without the presence of TFL fiber. There was no statistical difference (P>0.05) between stone ablation rates for single-use ball tip fiber (1.3±0.4 mg/s) (n=10), multiple-use ball tip fiber (1.3±0.5 mg/s) (n=44), and conventional single-use bare tip fibers (1.3±0.2 mg/s) (n=10). Ball tip durability varied widely, but fibers averaged greater than four stone procedures before failure, defined by rapid decline in stone ablation rates. Mechanical damage at the front surface of the ball tip was the limiting factor in fiber lifetime. The small fiber diameter did not significantly impact ureteroscope deflection or saline flow rates. The miniature ball tip fiber may provide a cost-effective design for safe fiber insertion through the ureteroscope working channel and into the ureter without risk of instrument damage or tissue perforation, and without compromising stone ablation efficiency during TFL lithotripsy.

16 CFR 1117.9 - Prohibited acts and sanctions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Prohibited acts and sanctions. 1117.9 Section 1117.9 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND OTHER SMALL...

Infants’ Looking to Surprising Events: When Eye-Tracking Reveals More than Looking Time

PubMed Central

Yeung, H. Henny; Denison, Stephanie; Johnson, Scott P.

2016-01-01

Research on infants’ reasoning abilities often rely on looking times, which are longer to surprising and unexpected visual scenes compared to unsurprising and expected ones. Few researchers have examined more precise visual scanning patterns in these scenes, and so, here, we recorded 8- to 11-month-olds’ gaze with an eye tracker as we presented a sampling event whose outcome was either surprising, neutral, or unsurprising: A red (or yellow) ball was drawn from one of three visible containers populated 0%, 50%, or 100% with identically colored balls. When measuring looking time to the whole scene, infants were insensitive to the likelihood of the sampling event, replicating failures in similar paradigms. Nevertheless, a new analysis of visual scanning showed that infants did spend more time fixating specific areas-of-interest as a function of the event likelihood. The drawn ball and its associated container attracted more looking than the other containers in the 0% condition, but this pattern was weaker in the 50% condition, and even less strong in the 100% condition. Results suggest that measuring where infants look may be more sensitive than simply how much looking there is to the whole scene. The advantages of eye tracking measures over traditional looking measures are discussed. PMID:27926920

Aerodynamic drag of modern soccer balls.

PubMed

Asai, Takeshi; Seo, Kazuya

2013-12-01

Soccer balls such as the Adidas Roteiro that have been used in soccer tournaments thus far had 32 pentagonal and hexagonal panels. Recently, the Adidas Teamgeist II and Adidas Jabulani, respectively having 14 and 8 panels, have been used at tournaments; the aerodynamic characteristics of these balls have not yet been verified. Now, the Adidas Tango 12, having 32 panels, has been developed for use at tournaments; therefore, it is necessary to understand its aerodynamic characteristics. Through a wind tunnel test and ball trajectory simulations, this study shows that the aerodynamic resistance of the new 32-panel soccer ball is larger in the high-speed region and lower in the middle-speed region than that of the previous 14- and 8-panel balls. The critical Reynolds number of the Roteiro, Teamgeist II, Jabulani, and Tango 12 was ~2.2 × 10(5) (drag coefficient, C d  ≈ 0.12), ~2.8 × 10(5) (C d  ≈ 0.13), ~3.3 × 10(5) (C d  ≈ 0.13), and ~2.4 × 10(5) (C d  ≈ 0.15), respectively. The flight trajectory simulation suggested that the Tango 12, one of the newest soccer balls, has less air resistance in the medium-speed region than the Jabulani and can thus easily acquire large initial velocity in this region. It is considered that the critical Reynolds number of a soccer ball, as considered within the scope of this experiment, depends on the extended total distance of the panel bonds rather than the small designs on the panel surfaces.

Do weather conditions correlate with findings in failed, provision-filled nest cells of Megachile rotundata (Hymenoptera: Megachilidae) in western North America?

PubMed

Pitts-Singer, Theresa L; James, Rosalind R

2008-06-01

Cavity-nesting alfalfa leafcutting bees, Megachile rotundata (F.) (Hymenoptera: Megachilidae), are excellent pollinators of alfalfa, Medicago savita L., for seed production. In commercial settings, artificial cavities are placed in field domiciles for nesting and, thereby, bee populations are sustained for future use. For this study, cells from leafcutting bee nests were collected in late summer from commercial seed fields. Over 3 yr (2003-2005), 39 samples in total of approximately equal to 1,000 cells each were taken from several northwestern U.S. states and from Manitoba, Canada. X-radiography of 500 cells from each sample was used to identify "pollen balls" (i.e., cells in which the pollen-nectar provision remained, but the egg or larva, if present, was not detectable on an x-radiograph). Most U.S. samples seemed to have higher proportions of pollen ball cells than Manitoba samples. Pollen ball cells were dissected to determine the moisture condition of the mass provision and true contents of each cell. Most pollen ball cells from Manitoba samples contained fungus, the frequency of which was positively correlated with cool, wet weather. In the United States, most pollen ball cells had moist provisions, and many of them lacked young brood. Correlation analysis revealed that pollen ball cells occurred in greater proportions in fields with more hot days (above 38 degrees C). Broodless pollen ball cells occurred in greater proportions under cool conditions, but dead small larvae (second-third instars) seemed to occur in greater proportions under hot conditions. Pollen ball cells with unhatched eggs and first instars (in the chorion) occurred in lesser proportions under hot conditions.

Fabrication of Aluminum Foams with Small Pore Size by Melt Foaming Method

NASA Astrophysics Data System (ADS)

Cheng, Ying; Li, Yanxiang; Chen, Xiang; Shi, Tong; Liu, Zhiyong; Wang, Ningzhen

2017-04-01

This article introduces an improvement to the fabrication of aluminum foams with small pore size by melt foaming method. Before added to the melt, the foaming agent (titanium hydride) was pretreated in two steps. It firstly went through the traditional pre-oxidation treatment, which delayed the decomposition of titanium hydride and made sure the dispersion stage was controllable. Then such pre-oxidized titanium hydride powder was mixed with copper powder in a planetary ball mill. This treatment can not only increase the number of foaming agent particles and make them easier to disperse in the melt, which helps to increase the number of pores, but also reduce the amount of hydrogen released in the foaming stage. Therefore, the pore size could be decreased. Using such a ball-milled foaming agent in melt foaming method, aluminum foams with small pore size (average size of 1.6 mm) were successfully fabricated.

A novel high-throughput imaging system for automated analyses of avoidance behavior in zebrafish larvae

PubMed Central

Pelkowski, Sean D.; Kapoor, Mrinal; Richendrfer, Holly A.; Wang, Xingyue; Colwill, Ruth M.; Creton, Robbert

2011-01-01

Early brain development can be influenced by numerous genetic and environmental factors, with long-lasting effects on brain function and behavior. The identification of these factors is facilitated by recent innovations in high-throughput screening. However, large-scale screening in whole organisms remains challenging, in particular when studying changes in brain function or behavior in vertebrate model systems. In this study, we present a novel imaging system for high-throughput analyses of behavior in zebrafish larvae. The three-camera system can image twelve multiwell plates simultaneously and is unique in its ability to provide local visual stimuli in the wells of a multiwell plate. The acquired images are converted into a series of coordinates, which characterize the location and orientation of the larvae. The developed imaging techniques were tested by measuring avoidance behaviors in seven-day-old zebrafish larvae. The system effectively quantified larval avoidance and revealed an increased edge preference in response to a blue or red ‘bouncing ball’ stimulus. Larvae also avoid a bouncing ball stimulus when it is counter-balanced with a stationary ball, but do not avoid blinking balls counter-balanced with a stationary ball. These results indicate that the seven-day-old larvae respond specifically to movement, rather than color, size, or local changes in light intensity. The imaging system and assays for measuring avoidance behavior may be used to screen for genetic and environmental factors that cause developmental brain disorders and for novel drugs that could prevent or treat these disorders. PMID:21549762

Eye on the B-ALL: B-cell receptor repertoires reveal persistence of numerous B-lymphoblastic leukemia subclones from diagnosis to relapse

PubMed Central

Bashford-Rogers, R J M; Nicolaou, K A; Bartram, J; Goulden, N J; Loizou, L; Koumas, L; Chi, J; Hubank, M; Kellam, P; Costeas, P A; Vassiliou, G S

2016-01-01

The strongest predictor of relapse in B-cell acute lymphoblastic leukemia (B-ALL) is the level of persistence of tumor cells after initial therapy. The high mutation rate of the B-cell receptor (BCR) locus allows high-resolution tracking of the architecture, evolution and clonal dynamics of B-ALL. Using longitudinal BCR repertoire sequencing, we find that the BCR undergoes an unexpectedly high level of clonal diversification in B-ALL cells through both somatic hypermutation and secondary rearrangements, which can be used for tracking the subclonal composition of the disease and detect minimal residual disease with unprecedented sensitivity. We go on to investigate clonal dynamics of B-ALL using BCR phylogenetic analyses of paired diagnosis-relapse samples and find that large numbers of small leukemic subclones present at diagnosis re-emerge at relapse alongside a dominant clone. Our findings suggest that in all informative relapsed patients, the survival of large numbers of clonogenic cells beyond initial chemotherapy is a surrogate for inherent partial chemoresistance or inadequate therapy, providing an increased opportunity for subsequent emergence of fully resistant clones. These results frame early cytoreduction as an important determinant of long-term outcome. PMID:27211266

Rolling ball sifting algorithm for the augmented visual inspection of carotid bruit auscultation

NASA Astrophysics Data System (ADS)

Huang, Adam; Lee, Chung-Wei; Liu, Hon-Man

2016-07-01

Carotid bruits are systolic sounds associated with turbulent blood flow through atherosclerotic stenosis in the neck. They are audible intermittent high-frequency (above 200 Hz) sounds mixed with background noise and transmitted low-frequency (below 100 Hz) heart sounds that wax and wane periodically. It is a nontrivial task to extract both bruits and heart sounds with high fidelity for further computer-aided auscultation and diagnosis. In this paper we propose a rolling ball sifting algorithm that is capable to filter signals with a sharper frequency selectivity mechanism in the time domain. By rolling two balls (one above and one below the signal) of a suitable radius, the balls are large enough to roll over bruits and yet small enough to ride on heart sound waveforms. The high-frequency bruits can then be extracted according to a tangibility criterion by using the local extrema touched by the balls. Similarly, the low-frequency heart sounds can be acquired by a larger radius. By visualizing the periodicity information of both the extracted heart sounds and bruits, the proposed visual inspection method can potentially improve carotid bruit diagnosis accuracy.

Superelastic Ball Bearings: Materials and Design to Avoid Mounting and Dismounting Brinell Damage in an Inaccessible Press-Fit Application-. I ; Design Approach

NASA Technical Reports Server (NTRS)

Dellacorte, Christopher; Howard, S. Adam

2015-01-01

Ball bearings require proper fit and installation into machinery structures (onto shafts and into bearing housings) to ensure optimal performance. For some applications, both the inner and outer race must be mounted with an interference fit and care must be taken during assembly and disassembly to avoid placing heavy static loads between the balls and races otherwise Brinell dent type damage can occur. In this paper, a highly dent resistant superelastic alloy, 60NiTi, is considered for rolling element bearing applications that encounter excessive static axial loading during assembly or disassembly. A small (R8) ball bearing is designed for an application in which access to the bearing races to apply disassembly tools is precluded. First Principles analyses show that by careful selection of materials, raceway curvature and land geometry, a bearing can be designed that allows blind assembly and disassembly without incurring raceway damage due to ball denting. Though such blind assembly applications are uncommon, the availability of bearings with unusually high static load capability may enable more such applications with additional benefits, especially for miniature bearings.

Experimental comparison and validation of hot-ball method with guarded hot plate method on polyurethane foams

NASA Astrophysics Data System (ADS)

Hudec, Ján; Glorieux, Christ; Dieška, Peter; Kubičár, Ľudovít

2016-07-01

The Hot-ball method is an innovative transient method for measuring thermophysical properties. The principle is based on heating of a small ball, incorporated in measured medium, by constant heating power and simultaneous measuring of the ball's temperature response since the heating was initiated. The shape of the temperature response depends on thermophysical properties of the medium, where the sensor is placed. This method is patented by Institute of Physics, SAS, where the method and sensors based on this method are being developed. At the beginning of the development of sensors for this method we were oriented on monitoring applications, where relative precision is much more important than accuracy. Meanwhile, the quality of sensors was improved good enough to be used for a new application - absolute measuring of thermophysical parameters of low thermally conductive materials. This paper describes experimental verification and validation of measurement by hot-ball method. Thanks to cooperation with Laboratory of Soft Matter and Biophysics of Catholic University of Leuven in Belgium, established Guarded Hot Plate method was used as a reference. Details about measuring setups, description of the experiments and results of the comparison are presented.

China Report, Political, Sociological and Military Affairs

DTIC Science & Technology

1985-01-29

of world attention , both the United States and the Soviet Union had emphasized the need for "sincerity" from the other side, kicking the ball to...systems and laws of this kind will not change because there is a change of the leader or because there is a change of the view and attention of a...system of this kind has a bearing on whether the party and the state will change their colors, which must be brought to the close attention of the

Volumetric dispenser for small particles from plural sources

DOEpatents

Bradley, R.A.; Miller, W.H.; Sease, J.D.

1975-12-16

Apparatus is described for rapidly and accurately dispensing measured volumes of small particles from a supply hopper. The apparatus includes an adjustable, vertically oriented measuring tube and orifice member defining the volume to be dispensed, a ball plug valve for selectively closing the bottom end of the orifice member, and a compression valve for selectively closing the top end of the measuring tube. A supply hopper is disposed above and in gravity flow communication with the measuring tube. Properly sequenced opening and closing of the two valves provides accurate volumetric discharge through the ball plug valve. A dispensing system is described wherein several appropriately sized measuring tubes, orifice members, and associated valves are arranged to operate contemporaneously to facilitate blending of different particles.

Water ball collision

NASA Technical Reports Server (NTRS)

Fujimoto, K.

1986-01-01

What happens if a stainless steel ball hits a water ball in the weightless space ot the Universe? In other words, it was the objective of our experiments in the Space to observe the surface tension of liquid by means of making a solid collide with a liquid. Place a small volume of water between 2 glass sheets to make a thin water membrane: the 2 glass sheets cannot be separated unless an enormous force is applied. It is obvious from this phenomenom that the surface tension of water is far greater than presumed. On Earth, however, it is impossible in most cases to observe only the surface tension of liquid, because gravity always acts on the surface tension. Water and stainless steel balls were chosen the liquid and solids for the experiments. Because water is the liquid most familiar to us, its properties are well known. And it is also of great interest to compare its properties on the Earth with those in the weightless space.

Evaluating the uniformity of color spaces and performance of color difference formulae

NASA Astrophysics Data System (ADS)

Lian, Yusheng; Liao, Ningfang; Wang, Jiajia; Tan, Boneng; Liu, Zilong

2010-11-01

Using small color difference data sets (Macadam ellipses dataset and RIT-DuPont suprathreshold color difference ellipses dataset), and large color difference data sets (Munsell Renovation Data and OSA Uniform Color Scales dataset), the uniformity of several color spaces and performance of color difference formulae based on these color spaces are evaluated. The color spaces used are CIELAB, DIN99d, IPT, and CIECAM02-UCS. It is found that the uniformity of lightness is better than saturation and hue. Overall, for all these color spaces, the uniformity in the blue area is inferior to the other area. The uniformity of CIECAM02-UCS is superior to the other color spaces for the whole color-difference range from small to large. The uniformity of CIELAB and IPT for the large color difference data sets is better than it for the small color difference data sets, but the DIN99d is opposite. Two common performance factors (PF/3 and STRESS) and the statistical F-test are calculated to test the performance of color difference formula. The results show that the performance of color difference formulae based on these four color spaces is consistent with the uniformity of these color spaces.

Temperature Measurement of Residual Penetration Fragments

DTIC Science & Technology

1977-07-01

three targets by the 1.27 cm annealed spheres. 16 800 at: 3 < UJ 5 8 600 o o o o 400 1.2 O = PLUG • » BALL L 1.4 1.6 m m... annealed projectiles. The radiographs of Figure 5 show soft and hard spheres after penetration of 12.7 mm targets. The hard metal breaks up into many small...861 and 862 provided the possibility of ball temperature measurement. 11 400 TEMPERATURE 600 , ’C 800 Figure 2. Calibration curves for steel

Hanging angles of two electrostatically repelling pith balls of different masses

NASA Astrophysics Data System (ADS)

Tran, Phuc G.; Mungan, Carl E.

2011-09-01

An analytic solution can be derived for the angles of two mutually repelling charged pith balls of unequal mass hanging from strings from a common point of attachment. Just as in the equal-mass case, a cubic equation is found for the square of the sine of either angle, and an approximation can be used to avoid Cardano's formula for small angles. These results extend a standard problem treated in introductory undergraduate courses in electricity and magnetism.

Small, high-speed bearing technology for cryogenic turbo-pumps

NASA Technical Reports Server (NTRS)

Winn, L. W.; Eusepi, M. W.; Smalley, A. J.

1974-01-01

The design of 20-mm bore ball bearings is described for cryogenic turbo-machinery applications, operating up to speeds of 120,000 rpm. A special section is included on the design of hybrid bearings. Each hybrid bearing is composed of a ball bearing in series with a conventional pressurized fluid-film journal bearing. Full details are presented on the design of a test vehicle which possesses the capability of testing the above named bearings within the given speed range under externally applied radial and axial loads.

Influence of ball milling on atomic structure and magnetic properties of Co{sub 40}Fe{sub 22}Ta{sub 8}B{sub 30} glassy alloy

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

Taghvaei, Amir Hossein, E-mail: Amirtaghvaei@gmail.com; Department of Materials Science and Engineering, Shiraz University of Technology, Shiraz; Stoica, Mihai

2014-06-01

The influence of ball milling on the atomic structure and magnetic properties of the Co{sub 40}Fe{sub 22}Ta{sub 8}B{sub 30} metallic glass with a high thermal stability and excellent soft magnetic properties has been investigated. After 14 h of milling, the obtained powders were found to consist mainly of an amorphous phase and a small fraction of the (Co,Fe){sub 21}Ta{sub 2}B{sub 6} nanocrystals. The changes in the reduced pair correlation functions suggest noticeable changes in the atomic structure of the amorphous upon ball milling. Furthermore, it has been shown that milling is accompanied by introduction of compressive and dilatational sites inmore » the glassy phase and increasing the fluctuation of the atomic-level hydrostatic stress without affecting the coordination number of the nearest neighbors. Ball milling has decreased the thermal stability and significantly affected the magnetic properties through increasing the saturation magnetization, Curie temperature of the amorphous phase and coercivity. - Highlights: • Ball milling affected the atomic structure of Co{sub 40}Fe{sub 22}Ta{sub 8}B{sub 30} metallic glass. • Mechanically-induced crystallization started after 4 h milling. • Milling increased the fluctuation of the atomic-level hydrostatic stress in glass. • Ball milling influenced the thermal stability and magnetic properties.« less

Physical characteristics that predict involvement with the ball in recreational youth soccer.

PubMed

Ré, Alessandro H Nicolai; Cattuzzo, Maria Teresa; Henrique, Rafael Dos Santos; Stodden, David F

2016-09-01

This study examined the relative contribution of age, stage of puberty, anthropometric characteristics, health-related fitness, soccer-specific tests and match-related technical performance to variance in involvements with the ball during recreational 5-a-side small-sided (32 × 15 m) soccer matches. Using a cross-sectional design, 80 healthy male students (14.6 ± 0.5 years of age; range 13.6-15.4) who played soccer recreationally were randomly divided into 10 teams and played against each other. Measurements included height, body mass, pubertal status, health-related fitness (12-min walk/run test, standing long jump, 15-m sprint and sit-ups in 30 s), soccer-specific tests (kicking for speed, passing for accuracy and agility run with and without a ball), match-related technical performance (kicks, passes and dribbles) and involvements with the ball during matches. Forward multiple regression analysis revealed that cardiorespiratory fitness (12-min walk/run test) accounted for 36% of the variance in involvements with the ball. When agility with the ball (zigzag running) and power (standing long jump) were included among the predictors, the total explained variance increased to 62%. In conclusion, recreational adolescent players, regardless of their soccer-specific skills, may increase participation in soccer matches most through physical activities that promote improvement in cardiorespiratory fitness, muscle power and agility.

16 CFR 1117.8 - Effect of reports on liability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Effect of reports on liability. 1117.8 Section 1117.8 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND OTHER SMALL...

Spin-bowling in cricket re-visited: model trajectories for various spin-vector angles

NASA Astrophysics Data System (ADS)

Robinson, Garry; Robinson, Ian

2016-08-01

In this paper we investigate, via the calculation of model trajectories appropriate to slow bowling in cricket, the effects on the flight path of the ball before pitching due to changes in the angle of the spin-vector. This was accomplished by allowing the spin-vector to vary in three ways. Firstly, from off-spin, where the spin-vector points horizontally and directly down the pitch, to top-spin where it points horizontally towards the off-side of the pitch. Secondly, from off-spin to side-spin where, for side-spin, the spin-vector points vertically upwards. Thirdly, where the spin-vector points horizontally and at 45° to the pitch (in the general direction of ‘point’, as viewed by the bowler), and is varied towards the vertical, while maintaining the 45° angle in the horizontal plane. It is found that, as is well known, top-spin causes the ball to dip in flight, side-spin causes the ball to move side-ways in flight and, perhaps most importantly, off-spin can cause the ball to drift to the off-side of the pitch late in its flight as it begins to fall. At a more subtle level it is found that, if the total spin is kept constant and a small amount of top-spin is added to the ball at the expense of some off-spin, there is little change in the side-ways drift. However, a considerable reduction in the length at which the ball pitches occurs, ˜25 cm, an amount that batsmen can ignore at their peril. On the other hand, a small amount of side-spin introduced to a top-spin delivery does not alter the point of pitching significantly, but produces a considerable amount of side-ways drift, ˜10 cm or more. For pure side-spin the side-ways drift is up to ˜30 cm. When a side-spin component is added to the spin of a ball bowled with a mixture of off-spin and top-spin in equal proportions, significant movement occurs in both the side-ways direction and in the point of pitching, of the order of a few tens of centimetres.

Ruptured eardrum

MedlinePlus

... as from a powerful slap or explosion) Inserting cotton-tipped swabs or small objects into the ears ... clean and dry while it is healing. Place cotton balls in the ear while showering or shampooing ...

An in situ occurrence of coal balls in the Amburgy coal bed, Pikeville Formation (Duckmantian), central Appalachian Basin, USA

USGS Publications Warehouse

Greb, S.F.; Eble, C.F.; Chesnut, D.R.; Phillips, T.L.; Hower, J.C.

1999-01-01

Carbonate concretions containing permineralized peat, commonly called coal balls, were encountered in the Amburgy coal, a generally low-ash (9.4%), but commonly high-sulfur (3.6%), Middle Pennsylvanian coal of the Eastern Kentucky Coal Field. These are the first coal balls from the Amburgy coal, and one of only a few reported occurrences from the central Appalachian Basin. The coal balls occur in the upper part of the coal, between two paleochannel cut-outs at the top of the Pikeville Formation, and immediately beneath a scour with a marine fossil lag at the base of the Kendrick Shale Member, Hyden Formation. The coal is thickest (1.3 m) in a narrow (<300 m), elongate depression between the bounding paleochannels, and thins toward the occurrence of coal balls. Total biovolume as measured from acetate peels of coal balls indicates cordaites or lycopsid (36.1% each) dominance. Vertical sampling through one coal-ball aggregate shows zoning from a lower cordaites-dominant (88.7%) assemblage, to a middle, degraded, sphenopsid-rich assemblage, to an upper lycopsid-dominant (88.6%) assemblage. Beneath the coal balls, palynologic and petrographic analyses indicate the basal and middle portions of the bed are dominated by arborescent lycopsid spores and cordaites pollen, and by vitrinite macerals. The top part of the bed, above the coal balls, contains increased intertinite macerals, increased percentages of small fern spores, and variable ash yield (5-21%). Thickening of the Amburgy coal along a structural low, in combination with basal high-ash yields, vitrinite-dominance, and heterogenous palynoflora, indicate paleotopographic control on initial peat accumulation. Abundant lycopsid spores in the basal and middle part of the coal reflect rheotrophic conditions consistent with accumulation in a paleotopographic depression. Apparent zonation preserved in one of the coal-ball masses may document plant successions in response to flooding. Similar percentages of cordaites and lycopods, respectively, in the zones above and below the degraded incursion interval reflect development of a mixed, successional pattern in response to the flooding. Coal-ball formation may have been facilitated by channeling along the Kendrick ravinement, within a paleotopographic depression, at the split margin of the Amburgy peat, either through direct transmittal of carbonates and marine waters into the peat, or through degassing of the peat beneath the scour.

A study of glasses-type color CGH using a color filter considering reduction of blurring

NASA Astrophysics Data System (ADS)

Iwami, Saki; Sakamoto, Yuji

2009-02-01

We have developed a glasses-type color computer generated hologram (CGH) by using a color filter. The proposed glasses consist of two "lenses" made of overlapping holograms and color filters. The holograms, which are calculated to reconstruct images in each primary color, are divided to small areas, which we called cells, and superimposed on one hologram. In the same way, colors of the filter correspond to the hologram cells. We can configure it very simply without a complex optical system, and the configuration yields a small and light weight system suitable for glasses. When the cell is small enough, the colors are mixed and reconstructed color images are observed. In addition, color expression of reconstruction images improves, too. However, using small cells blurrs reconstructed images because of the following reasons: (1) interference between cells because of the correlation with the cells, and (2) reduction of resolution caused by the size of the cell hologram. We are investigating in order to make a hologram that has high resolution reconstructed color images without ghost images. In this paper, we discuss (1) the details of the proposed glasses-type color CGH, (2) appropriate cell size for an eye system, (3) effects of cell shape on the reconstructed images, and (4) a new method to reduce the blurring of the images.

Ball Lightning–Aerosol Electrochemical Power Source or A Cloud of Batteries

PubMed Central

2007-01-01

Despite numerous attempts, an adequate theoretical and experimental simulation of ball lightning still remains incomplete. According to the model proposed here, the processes of electrochemical oxidation within separate aerosol particles are the basis for this phenomenon, and ball lightning is a cloud of composite nano or submicron particles, where each particle is a spontaneously formed nanobattery which is short-circuited by the surface discharge because it is of such a small size. As free discharge-shorted current loops, aerosol nanobatteries are exposed to a powerful mutual magnetic dipole–dipole attraction. The gaseous products and thermal energy produced by each nanobattery as a result of the intra-particle self-sustaining electrochemical reactions, cause a mutual repulsion of these particles over short distances and prevent their aggregation, while a collectivization of the current loops of separate particles, due to the electric arc overlapping between adjacent particles, weakens their mutual magnetic attraction over short distances. Discharge currents in the range of several amperes to several thousand amperes as well as the pre-explosive mega ampere currents, generated in the reduction–oxidation reactions and distributed between all the aerosol particles, explain both the magnetic attraction between the elements of the ball lightning substance and the impressive electromagnetic effects of ball lightning.

Spatiotemporal characteristics of muscle patterns for ball catching

PubMed Central

D'Andola, M.; Cesqui, B.; Portone, A.; Fernandez, L.; Lacquaniti, F.; d'Avella, A.

2013-01-01

What sources of information and what control strategies the central nervous system (CNS) uses to perform movements that require accurate sensorimotor coordination, such as catching a flying ball, is still debated. Here we analyzed the EMG waveforms recorded from 16 shoulder and elbow muscles in six subjects during catching of balls projected frontally from a distance of 6 m and arriving at two different heights and with three different flight times (550, 650, 750 ms). We found that a large fraction of the variation in the muscle patterns was captured by two time-varying muscle synergies, coordinated recruitment of groups of muscles with specific activation waveforms, modulated in amplitude and shifted in time according to the ball's arrival height and flight duration. One synergy was recruited with a short and fixed delay from launch time. Remarkably, a second synergy was recruited at a fixed time before impact, suggesting that it is timed according to an accurate time-to-contact estimation. These results suggest that the control of interceptive movements relies on a combination of reactive and predictive processes through the intermittent recruitment of time-varying muscle synergies. Knowledge of the dynamic effect of gravity and drag on the ball may be then implicitly incorporated in a direct mapping of visual information into a small number of synergy recruitment parameters. PMID:23966939

Complete analytical solution of electromagnetic field problem of high-speed spinning ball

NASA Astrophysics Data System (ADS)

Reichert, T.; Nussbaumer, T.; Kolar, J. W.

2012-11-01

In this article, a small sphere spinning in a rotating magnetic field is analyzed in terms of the resulting magnetic flux density distribution and the current density distribution inside the ball. From these densities, the motor torque and the eddy current losses can be calculated. An analytical model is derived, and its results are compared to a 3D finite element analysis. The model gives insight into the torque and loss characteristics of a solid rotor induction machine setup, which aims at rotating the sphere beyond 25 Mrpm.

Dynamic, High-Temperature, Flexible Seal

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M.; Sirocky, Paul J.

1989-01-01

New seal consists of multiple plies of braided ceramic sleeves filled with small ceramic balls. Innermost braided sleeve supported by high-temperature-wire-mesh sleeve that provides both springback and preload capabilities. Ceramic balls reduce effect of relatively high porosity of braided ceramic sleeves by acting as labyrinth flow path for gases and thereby greatly increasing pressure gradient seal can sustain. Dynamic, high-temperature, flexible seal employed in hypersonic engines, two-dimensional convergent/divergent and vectorized-thrust exhaust nozzles, reentry vehicle airframes, rocket-motor casings, high-temperature furnaces, and any application requiring non-asbestos high-temperature gaskets.

Angular Motion of Projectiles with a Moving Internal Part.

DTIC Science & Technology

1977-02-01

Ball Rotor T317 hellIntermal Projectile RingsM505 Fuze Quasi-linear Angular Motion N\\ ANSTRACT (-jCanhs si rveree side ff naeweemv end identify by...LIST OF FIGURES Figure Page 1. 20mm Shell T282E1 with Arming Ball Rotor .... .......... 20 2. Fast Mode Damping Rate for the 20mm T282E1...fuze has a spherical arming rotor in a cylindrical cavity with small but non-zero clearanc’es (Figure 1). The fourth sa.ell - the 8-inch T317 - showed

16 CFR 1117.6 - Relation to section 15(b) of the CPSA.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Relation to section 15(b) of the CPSA. 1117.6 Section 1117.6 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS REPORTING OF CHOKING INCIDENTS INVOLVING MARBLES, SMALL BALLS, LATEX BALLOONS AND OTHER SMALL...

78 FR 61443 - Small Business Size Standards: Waiver of the Nonmanufacturer Rule

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-03

... to rescind the Class Waiver of the Nonmanufacturer Rule (NMR) for Aerospace Ball and Roller Bearings... accessed by accessing the following URL: http://www.sba.gov/sites/default/files/files/NMR_WAIVED_3110... roller bearings manufactured by small businesses, unless an Individual Waiver of the NMR is granted by...

Big Policies and a Small World: An Analysis of Policy Problems and Solutions in Physical Education

ERIC Educational Resources Information Center

Penney, Dawn

2017-01-01

This paper uses Ball's [1998. Big policies/small world: An introduction to international perspectives in education policy. "Comparative Education," 34(2), 119-130] policy analysis and Bernstein's [1990. "The structuring of pedagogic discourse. Volume IV class, codes and control". London: Routledge; 2000, "Pedagogy,…

Biomechanical Effects of the Geometry of Ball-and-Socket Artificial Disc on Lumbar Spine: A Finite Element Study.

PubMed

Choi, Jisoo; Shin, Dong-Ah; Kim, Sohee

2017-03-15

A three-dimensional finite element model of intact lumbar spine was constructed and four surgical finite element models implanted with ball-and-socket artificial discs with four different radii of curvature were compared. To investigate biomechanical effects of the curvature of ball-and-socket artificial disc using finite element analysis. Total disc replacement (TDR) has been accepted as an alternative treatment because of its advantages over spinal fusion methods in degenerative disc disease. However, the influence of the curvature of artificial ball-and-socket discs has not been fully understood. Four surgical finite element models with different radii of curvature of ball-and-socket artificial discs were constructed. The range of motion (ROM) increased with decreasing radius of curvature in extension, flexion, and lateral bending, whereas it increased with increasing radius of curvature in axial torsion. The facet contact force was minimum with the largest radius of curvature in extension, flexion, and lateral bending, whereas it was maximum with the largest radius in axial torsion. It was also affected by the disc placement, more with posterior placement than anterior placement. The stress in L4 cancellous bone increased when the radius of curvature was too large or small. The geometry of ball-and-socket artificial disc significantly affects the ROM, facet contact force, and stress in the cancellous bone at the surgical level. The implication is that in performing TDR, the ball-and-socket design may not be ideal, as ROM and facet contact force are sensitive to the disc design, which may be exaggerated by the individual difference of anatomical geometry. N/A.

Effect of Internal Clearance on Load Distribution and Life of Radially Loaded Ball and Roller Bearings

NASA Technical Reports Server (NTRS)

Oswald, Fred B.; Zaretsky, Erwin V.; Poplawski, Joseph V.

2012-01-01

The effect of internal clearance on radially loaded deepgroove ball and cylindrical roller bearing load distribution and fatigue life was determined for four clearance groups defined in the bearing standards. The analysis was extended to negative clearance (interference) conditions to produce a curve of life factor versus internal clearance. Rolling-element loads can be optimized and bearing life maximized for a small negative operating clearance. Life declines gradually with positive clearance and rapidly with increasing negative clearance. Relationships were found between bearing life and internal clearance as a function of ball or roller diameter, adjusted for load. Results are presented as life factors for radially loaded bearings independent of bearing size or applied load. In addition, a modified Stribeck Equation is presented that relates the maximum rolling-element load to internal bearing clearance.

RosettaHoles: rapid assessment of protein core packing for structure prediction, refinement, design, and validation.

PubMed

Sheffler, Will; Baker, David

2009-01-01

We present a novel method called RosettaHoles for visual and quantitative assessment of underpacking in the protein core. RosettaHoles generates a set of spherical cavity balls that fill the empty volume between atoms in the protein interior. For visualization, the cavity balls are aggregated into contiguous overlapping clusters and small cavities are discarded, leaving an uncluttered representation of the unfilled regions of space in a structure. For quantitative analysis, the cavity ball data are used to estimate the probability of observing a given cavity in a high-resolution crystal structure. RosettaHoles provides excellent discrimination between real and computationally generated structures, is predictive of incorrect regions in models, identifies problematic structures in the Protein Data Bank, and promises to be a useful validation tool for newly solved experimental structures.

RosettaHoles: Rapid assessment of protein core packing for structure prediction, refinement, design, and validation

PubMed Central

Sheffler, Will; Baker, David

2009-01-01

We present a novel method called RosettaHoles for visual and quantitative assessment of underpacking in the protein core. RosettaHoles generates a set of spherical cavity balls that fill the empty volume between atoms in the protein interior. For visualization, the cavity balls are aggregated into contiguous overlapping clusters and small cavities are discarded, leaving an uncluttered representation of the unfilled regions of space in a structure. For quantitative analysis, the cavity ball data are used to estimate the probability of observing a given cavity in a high-resolution crystal structure. RosettaHoles provides excellent discrimination between real and computationally generated structures, is predictive of incorrect regions in models, identifies problematic structures in the Protein Data Bank, and promises to be a useful validation tool for newly solved experimental structures. PMID:19177366

A novel disturbance-observer based friction compensation scheme for ball and plate system.

PubMed

Wang, Yongkun; Sun, Mingwei; Wang, Zenghui; Liu, Zhongxin; Chen, Zengqiang

2014-03-01

Friction is often ignored when designing a controller for the ball and plate system, which can lead to steady-error and stick-slip phenomena, especially for the small amplitude command. It is difficult to achieve high-precision control performance for the ball and plate system because of its friction. A novel reference compensation strategy is presented to attenuate the aftereffects caused by the friction. To realize this strategy, a linear control law is proposed based on a reduced-order observer. Neither the accurate friction model nor the estimation of specific characteristic parameters is needed in this design. Moreover, the describing function method illustrates that the limit cycle can be avoided. Finally, the comparative mathematical simulations and the practical experiments are used to validate the effectiveness of the proposed method. © 2013 ISA Published by ISA All rights reserved.

Shipyard Marking Methods

DTIC Science & Technology

1980-09-01

K ( 7 ) D , SOAPSTONE ( 1 3 ) E. lNK (5) F. CRAYON OR PAINT STICK (14) G.DYE (1) H . PE N C I L ( 1 ) 1. ELECTRIC ENGRAVING (1) 2. WHO MANUFACTURES...CHALK ( 2 ) D . DYE (1) H, SOAPSTONE (4) 4. W HAT TYPE OF DISPENSING METHOD IS UTILIZED WITH MARKING MATERIALS? A . BALL POINT TUBE ( 1 3 ) H , STEEL...9 ) L, BAMBOO PEN & INK POT F. SOAPSTONE (12) M . OIL PENCIL ( 1 ) G . L A C S T I C K ( 0 ) N . ELECTRI c ENGRAVER (1) 5, ARE STANDARD COLORS

SPHERES Slosh Run

NASA Image and Video Library

2014-01-22

ISS038-E-033888 (22 Jan. 2014) --- A new experiment using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES, already on the station, is featured in this image photographed by an Expedition 38 crew member in the International Space Station's Kibo laboratory. For the SPHERES-Slosh experiment, two SPHERES robots are attached to opposite ends of a metal frame holding a plastic tank with green-colored water. The new hardware for the SPHERES-Slosh study was delivered to the station aboard Orbital Sciences' Cygnus cargo craft on Jan. 12.

SPHERES Slosh Run

NASA Image and Video Library

2014-01-22

ISS038-E-033890 (22 Jan. 2014) --- In the International Space Station's Kibo laboratory, NASA astronaut Mike Hopkins, Expedition 38 flight engineer, works with a new experiment using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES, which are already on the station. For the SPHERES-Slosh experiment, two SPHERES robots are attached to opposite ends of a metal frame holding the plastic tank with the green-colored water. The new hardware for the SPHERES-Slosh study was delivered to the station aboard Orbital Sciences' Cygnus cargo craft on Jan. 12.

Gas Release Behavior of Cu-TiH2 Composite Powder and Its Application as a Blowing Agent to Fabricate Aluminum Foams with Low Porosity and Small Pore Size

NASA Astrophysics Data System (ADS)

Cheng, Ying; Li, Yanxiang; Chen, Xiang; Liu, Zhiyong; Zhou, Xu; Wang, Ningzhen

2018-06-01

Compared to traditional pore structure with high porosity (≥ 80 pct) and large pore size (≥ 3 mm), aluminum foams with low porosity (60 to 70 pct) and small pore size (≤ 2 mm) possess higher compressive property and formability. In order to achieve the goal of reducing pore size, Cu-TiH2 composite powder prepared by ball milling preoxidized TiH2 with Cu powder was used as a blowing agent. Its gas release behavior was characterized by thermogravimetric analysis and differential scanning calorimetry. The results show that the ball milling treatment can advance the gas release process and slow the gas release rate at the same time. All these changes are favorable to the reduction of porosity and pore size. Such Cu-TiH2 composite powder provides an alternative way to fabricate aluminum foams with low porosity and small pore size.

Voyager 2 Color Image of Enceladus, Almost Full Disk

NASA Technical Reports Server (NTRS)

1990-01-01

This color Voyager 2 image mosaic shows the water-ice-covered surface of Enceladus, one of Saturn's icy moons. Enceladus' diameter of just 500 km would fit across the state of Arizona, yet despite its small size Enceladus exhibits one of the most interesting surfaces of all the icy satellites. Enceladus reflects about 90% of the incident sunlight (about like fresh-fallen snow), placing it among the most reflective objects in the Solar System. Several geologic terrains have superposed crater densities that span a factor of at least 500, thereby indicating huge differences in the ages of these terrains. It is possible that the high reflectivity of Enceladus' surface results from continuous deposition of icy particles from Saturn's E-ring, which in fact may originate from icy volcanoes on Enceladus' surface. Some terrains are dominated by sinuous mountain ridges from 1 to 2 km high (3300 to 6600 feet), whereas other terrains are scarred by linear cracks, some of which show evidence for possible sideways fault motion such as that of California's infamous San Andreas fault. Some terrains appear to have formed by separation of icy plates along cracks, and other terrains are exceedingly smooth at the resolution of this image. The implication carried by Enceladus' surface is that this tiny ice ball has been geologically active and perhaps partially liquid in its interior for much of its history. The heat engine that powers geologic activity here is thought to be elastic deformation caused by tides induced by Enceladus' orbital motion around Saturn and the motion of another moon, Dione.

Target size matters: target errors contribute to the generalization of implicit visuomotor learning.

PubMed

Reichenthal, Maayan; Avraham, Guy; Karniel, Amir; Shmuelof, Lior

2016-08-01

The process of sensorimotor adaptation is considered to be driven by errors. While sensory prediction errors, defined as the difference between the planned and the actual movement of the cursor, drive implicit learning processes, target errors (e.g., the distance of the cursor from the target) are thought to drive explicit learning mechanisms. This distinction was mainly studied in the context of arm reaching tasks where the position and the size of the target were constant. We hypothesize that in a dynamic reaching environment, where subjects have to hit moving targets and the targets' dynamic characteristics affect task success, implicit processes will benefit from target errors as well. We examine the effect of target errors on learning of an unnoticed perturbation during unconstrained reaching movements. Subjects played a Pong game, in which they had to hit a moving ball by moving a paddle controlled by their hand. During the game, the movement of the paddle was gradually rotated with respect to the hand, reaching a final rotation of 25°. Subjects were assigned to one of two groups: The high-target error group played the Pong with a small ball, and the low-target error group played with a big ball. Before and after the Pong game, subjects performed open-loop reaching movements toward static targets with no visual feedback. While both groups adapted to the rotation, the postrotation reaching movements were directionally biased only in the small-ball group. This result provides evidence that implicit adaptation is sensitive to target errors. Copyright © 2016 the American Physiological Society.

16 CFR 1117.1 - Purpose.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., distributor, retailer, and importer of a marble, small ball, or latex balloon, or a toy or a game that... or game and, as a result of that incident the child died, suffered serious injury, ceased breathing...

16 CFR 1117.1 - Purpose.

Code of Federal Regulations, 2012 CFR

2012-01-01

... or game and, as a result of that incident the child died, suffered serious injury, ceased breathing..., distributor, retailer, and importer of a marble, small ball, or latex balloon, or a toy or a game that...

16 CFR 1117.1 - Purpose.

Code of Federal Regulations, 2011 CFR

2011-01-01

... or game and, as a result of that incident the child died, suffered serious injury, ceased breathing..., distributor, retailer, and importer of a marble, small ball, or latex balloon, or a toy or a game that...

16 CFR 1117.1 - Purpose.

Code of Federal Regulations, 2014 CFR

2014-01-01

... or game and, as a result of that incident the child died, suffered serious injury, ceased breathing..., distributor, retailer, and importer of a marble, small ball, or latex balloon, or a toy or a game that...

Space to ground talking through small different areas in the top part of the air where the space-house flies.

NASA Astrophysics Data System (ADS)

Heine, T.

2015-12-01

If you look between the middle and the top of the ball of rock on which we all live, the very excited part of the top air (as high as where the space-house flies) doesn't change much on a normal day. In fact, it is very much the same in every direction. However, sometimes when there is sudden, heavy wind from the sun, the excited top air can be different and changing, becoming more or less filled up, in many directions---especially if you look at toward the top and the right of the ball of rock on which we all live. Some of the excited top air becomes suddenly filled up in one big area. Near there, there are also parts of the the excited top air that start changing in many very small places. These small changing areas sometimes make it hard to talk between space and the ground. We studied this happening on days on and around day 17 of third month of 2015 when the wind from the sun hit the ball of rock on which we all live very hard. We used things that talk from space to the ground in an area around school up to several hundred 5280 feet away. We made pictures of the changing excited top air, especially the small changing places, and looked for when they did and didn't make for good talking from space to the ground. We studied these pictures to learn when and why this sometimes happens and sometimes it doesn't. We are excited to share what we learned with you.

Gage for micromachining system

DOEpatents

Miller, Donald M.

1979-02-27

A gage for measuring the contour of the surface of an element of a micromachining tool system and of a work piece machined by the micromachining tool system. The gage comprises a glass plate containing two electrical contacts and supporting a steel ball resting against the contacts. As the element or workpiece is moved against the steel ball, the very slight contact pressure causes an extremely small movement of the steel ball which breaks the electrical circuit between the two contacts. The contour information is supplied to a dedicated computer controlling the micromachining tool so that the computer knows the contour of the element and the work piece to an accuracy of .+-. 25 nm. The micromachining tool system with X- and omega-axes is used to machine spherical, aspherical, and irregular surfaces with a maximum contour error of 100 nanometers (nm) and surface waviness of no more than 0.8 nm RMS.

Application of double laser interferometer in the measurement of translational stages' roll characteristics

NASA Astrophysics Data System (ADS)

Jin, Tao; Shen, Lu; Ke, Youlong; Hou, Wenmei; Ju, Aisong; Yang, Wei; Luo, Jialin

2016-10-01

In order to achieve rapid measurement of larger travel translation stages' roll-angle error in industry and to study the roll characteristics, this paper designs a small roll-angle measurement system based on laser heterodyne interferometry technology, test and researched on the roll characteristics of ball screw linear translation stage to fill the blank of the market. The results show that: during the operation of the ball screw linear translation stage, the workbench's roll angle changes complexly, its value is not only changing with different positions, but also shows different levels of volatility, what's more, the volatility varies with the workbench's work speed . Because of the non uniform stiffness of ball screw, at the end of each movement, the elastic potential energy being stored from the working process should release slowly, and the workbench will cost a certain time to roll fluctuate before it achieves a stable tumbling again.

Saccular lung cannulation in a ball python (Python regius) to treat a tracheal obstruction.

PubMed

Myers, Debbie A; Wellehan, James F X; Isaza, Ramiro

2009-03-01

An adult male ball python (Python regius) presented in a state of severe dyspnea characterized by open-mouth breathing and vertical positioning of the head and neck. The animal had copious discharge in the tracheal lumen acting as an obstruction. A tube was placed through the body wall into the caudal saccular aspect of the lung to allow the animal to breathe while treatment was initiated. The ball python's dyspnea immediately improved. Diagnostics confirmed a bacterial respiratory infection with predominantly Providencia rettgeri. The saccular lung (air sac) tube was removed after 13 days. Pulmonary endoscopy before closure showed minimal damage with a small amount of hemorrhage in the surrounding muscle tissue. Respiratory disease is a common occurrence in captive snakes and can be associated with significant morbidity and mortality. Saccular lung cannulation is a relatively simple procedure that can alleviate tracheal narrowing or obstruction, similar to air sac cannulation in birds.

Relative locality and the soccer ball problem

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

Amelino-Camelia, Giovanni; Freidel, Laurent; Smolin, Lee

We consider the behavior of macroscopic bodies within the framework of relative locality [G. Amelino-Camelia, L. Freidel, J. Kowalski-Glikman, and L. Smolin, arXiv:1101.0931]. This is a recent proposal for Planck scale modifications of the relativistic dynamics of particles which are described as arising from deformations in the geometry of momentum space. We consider and resolve a common objection against such proposals, which is that, even if the corrections are small for elementary particles in current experiments, they are huge when applied to composite systems such as soccer balls, planets, and stars, with energies E{sub macro} much larger than M{sub P}.more » We show that this soccer ball problem does not arise within the framework of relative locality because the nonlinear effects for the dynamics of a composite system with N elementary particles appear at most of order E{sub macro}/N{center_dot}M{sub P}.« less

16 CFR § 1117.1 - Purpose.

Code of Federal Regulations, 2013 CFR

2013-01-01

... or game and, as a result of that incident the child died, suffered serious injury, ceased breathing..., distributor, retailer, and importer of a marble, small ball, or latex balloon, or a toy or a game that...

Genetic variations associated with six-white-point coat pigmentation in Diannan small-ear pigs

PubMed Central

Lü, Meng-Die; Han, Xu-Man; Ma, Yun-Fei; Irwin, David M.; Gao, Yun; Deng, Jia-Kun; Adeola, Adeniyi C.; Xie, Hai-Bing; Zhang, Ya-Ping

2016-01-01

A common phenotypic difference among domestic animals is variation in coat color. Six-white-point is a pigmentation pattern observed in varying pig breeds, which seems to have evolved through several different mechanistic pathways. Herein, we re-sequenced whole genomes of 31 Diannan small-ear pigs from China and found that the six-white-point coat color in Diannan small-ear pigs is likely regulated by polygenic loci, rather than by the MC1R locus. Strong associations were observed at three loci (EDNRB, CNTLN, and PINK1), which explain about 20 percent of the total coat color variance in the Diannan small-ear pigs. We found a mutation that is highly differentiated between six-white-point and black Diannan small-ear pigs, which is located in a conserved noncoding sequence upstream of the EDNRB gene and is a putative binding site of the CEBPB protein. This study advances our understanding of coat color evolution in Diannan small-ear pigs and expands our traditional knowledge of coat color being a monogenic trait. PMID:27270507

Water color affects the stratification, surface temperature, heat content, and mean epilimnetic irradiance of small lakes

USGS Publications Warehouse

Houser, J.N.

2006-01-01

The effects of water color on lake stratification, mean epilimnetic irradiance, and lake temperature dynamics were examined in small, north-temperate lakes that differed widely in water color (1.5-19.8 m -1). Among these lakes, colored lakes differed from clear lakes in the following ways: (i) the epilimnia were shallower and colder, and mean epilimnetic irradiance was reduced; (ii) the diel temperature cycles were more pronounced; (iii) whole-lake heat accumulation during stratification was reduced. The depth of the epilimnion ranged from 2.5 m in the clearest lake to 0.75 m in the most colored lake, and 91% of the variation in epilimnetic depth was explained by water color. Summer mean morning epilimnetic temperature was ???2??C cooler in the most colored lake compared with the clearest lake. In clear lakes, the diel temperature range (1.4 ?? 0.7??C) was significantly (p = 0.01) less than that in the most colored lake (2.1 ?? 1.0??C). Change in whole-lake heat content was negatively correlated with water color. Increasing water color decreased light penetration more than thermocline depth, leading to reduced mean epilimnetic irradiance in the colored lakes. Thus, in these small lakes, water color significantly affected temperature, thermocline depth, and light climate. ?? 2006 NRC.

Experiment in Assessing Color Separation Techniques for Identifying Small Density Variations in Tires

DOT National Transportation Integrated Search

1972-07-01

An experimental color system was tested as an adjunct to the X-ray fluoroscopy system already in use. Shades of gray were translated into various colors as a means of enhancing small defects normally observed with difficulty, and to provide for more ...

Colorization-Based RGB-White Color Interpolation using Color Filter Array with Randomly Sampled Pattern

PubMed Central

Oh, Paul; Lee, Sukho; Kang, Moon Gi

2017-01-01

Recently, several RGB-White (RGBW) color filter arrays (CFAs) have been proposed, which have extra white (W) pixels in the filter array that are highly sensitive. Due to the high sensitivity, the W pixels have better SNR (Signal to Noise Ratio) characteristics than other color pixels in the filter array, especially, in low light conditions. However, most of the RGBW CFAs are designed so that the acquired RGBW pattern image can be converted into the conventional Bayer pattern image, which is then again converted into the final color image by using conventional demosaicing methods, i.e., color interpolation techniques. In this paper, we propose a new RGBW color filter array based on a totally different color interpolation technique, the colorization algorithm. The colorization algorithm was initially proposed for colorizing a gray image into a color image using a small number of color seeds. Here, we adopt this algorithm as a color interpolation technique, so that the RGBW color filter array can be designed with a very large number of W pixels to make the most of the highly sensitive characteristics of the W channel. The resulting RGBW color filter array has a pattern with a large proportion of W pixels, while the small-numbered RGB pixels are randomly distributed over the array. The colorization algorithm makes it possible to reconstruct the colors from such a small number of RGB values. Due to the large proportion of W pixels, the reconstructed color image has a high SNR value, especially higher than those of conventional CFAs in low light condition. Experimental results show that many important information which are not perceived in color images reconstructed with conventional CFAs are perceived in the images reconstructed with the proposed method. PMID:28657602

Colorization-Based RGB-White Color Interpolation using Color Filter Array with Randomly Sampled Pattern.

PubMed

Oh, Paul; Lee, Sukho; Kang, Moon Gi

2017-06-28

Recently, several RGB-White (RGBW) color filter arrays (CFAs) have been proposed, which have extra white (W) pixels in the filter array that are highly sensitive. Due to the high sensitivity, the W pixels have better SNR (Signal to Noise Ratio) characteristics than other color pixels in the filter array, especially, in low light conditions. However, most of the RGBW CFAs are designed so that the acquired RGBW pattern image can be converted into the conventional Bayer pattern image, which is then again converted into the final color image by using conventional demosaicing methods, i.e., color interpolation techniques. In this paper, we propose a new RGBW color filter array based on a totally different color interpolation technique, the colorization algorithm. The colorization algorithm was initially proposed for colorizing a gray image into a color image using a small number of color seeds. Here, we adopt this algorithm as a color interpolation technique, so that the RGBW color filter array can be designed with a very large number of W pixels to make the most of the highly sensitive characteristics of the W channel. The resulting RGBW color filter array has a pattern with a large proportion of W pixels, while the small-numbered RGB pixels are randomly distributed over the array. The colorization algorithm makes it possible to reconstruct the colors from such a small number of RGB values. Due to the large proportion of W pixels, the reconstructed color image has a high SNR value, especially higher than those of conventional CFAs in low light condition. Experimental results show that many important information which are not perceived in color images reconstructed with conventional CFAs are perceived in the images reconstructed with the proposed method.

Anthocyanin and Carotenoid Contents in Different Cultivars of Chrysanthemum (Dendranthema grandiflorum Ramat.) Flower.

PubMed

Park, Chang Ha; Chae, Soo Cheon; Park, Soo-Yun; Kim, Jae Kwang; Kim, Yong Joo; Chung, Sun Ok; Arasu, Mariadhas Valan; Al-Dhabi, Naif Abdullah; Park, Sang Un

2015-06-15

The flowers of twenty-three cultivars of Dendranthema grandiflorum Ramat. were investigated to determine anthocyanin and carotenoid levels and to confirm the effects of the pigments on the flower colors using high-performance liquid chromatography (HPLC) and electrospray ionization-mass spectrometry (ESI-MS). The cultivars contained the anthocyanins cyanidin 3-glucoside (C3g) and cyanidin 3-(3"-malonoyl) glucoside (C3mg) and the following carotenoids: lutein, zeaxanthin, β-cryptoxanthin, 13-cis-β-carotene, α-carotene, trans-β-carotene, and 9-cis-β-carotene. The cultivar "Magic" showed the greatest accumulation of total and individual anthocyanins, including C3g and C3gm. On the other hand, the highest level of lutein and zeaxanthin was noted in the cultivar "Il Weol". The cultivar "Anastasia" contained the highest amount of carotenoids such as trans-β-carotene, 9-cis-β-carotene, and 13-cis-β-carotene. The highest accumulation of β-cryptoxanthin and α-carotene was noted in the cultivar "Anastasia" and "Il Weol". Our results suggested that 'Magic", "Angel" and "Relance' had high amounts of anthocyanins and showed a wide range of red and purple colors in their petals, whereas "Il Weol', "Popcorn Ball' and "Anastasia" produced higher carotenoid contents and displayed yellow or green petal colors. Interestingly, "Green Pang Pang", which contained a high level of anthocyanins and a medium level of carotenoids, showed the deep green colored petals. "Kastelli", had high level of carotenoids as well as a medium level of anthocyanins and showed orange and red colored petals. It was concluded that each pigment is responsible for the petal's colors and the compositions of the pigments affect their flower colors and that the cultivars could be a good source for pharmaceutical, floriculture, and pigment industries.

Adaptability of expert visual anticipation in baseball batting.

PubMed

Müller, Sean; Fadde, Peter J; Harbaugh, Allen G

2017-09-01

By manipulating stimulus variation in terms of opponent pitcher actions, this study investigated the capability of expert (n = 30) and near-expert (n = 95) professional baseball batters to adapt anticipation skill when using the video simulation temporal occlusion paradigm. Participants watched in-game footage of two pitchers, one after the other, that was temporally occluded at ball release and various points during ball flight. They were required to make a written prediction of pitch types and locations. Per cent accuracy was calculated for pitch type, for pitch location, and for type and location combined. Results indicated that experts and near-experts could adapt their anticipation to predict above guessing level across both pitchers, but adaptation to the left-handed pitcher was poorer than the right-handed pitcher. Small-to-moderate effect sizes were found in terms of superior adaptation by experts over near-experts at the ball release and early ball flight occlusion conditions. The findings of this study extend theoretical and applied knowledge of expertise in striking sports. Practical application of the instruments and findings are discussed in terms of applied researchers, practitioners and high-performance staff in professional sporting organisations.

On Developing a Taxonomy for Multidisciplinary Design Optimization: A Decision-Based Perspective

NASA Technical Reports Server (NTRS)

Lewis, Kemper; Mistree, Farrokh

1995-01-01

In this paper, we approach MDO from a Decision-Based Design (DBD) perspective and explore classification schemes for designing complex systems and processes. Specifically, we focus on decisions, which are only a small portion of the Decision Support Problem (DSP) Technique, our implementation of DBD. We map coupled nonhierarchical and hierarchical representations from the DSP Technique into the Balling-Sobieski (B-S) framework (Balling and Sobieszczanski-Sobieski, 1994), and integrate domain-independent linguistic terms to complete our taxonomy. Application of DSPs to the design of complex, multidisciplinary systems include passenger aircraft, ships, damage tolerant structural and mechanical systems, and thermal energy systems. In this paper we show that Balling-Sobieski framework is consistent with that of the Decision Support Problem Technique through the use of linguistic entities to describe the same type of formulations. We show that the underlying linguistics of the solution approaches are the same and can be coalesced into a homogeneous framework with which to base the research, application, and technology MDO upon. We introduce, in the Balling-Sobieski framework, examples of multidisciplinary design, namely, aircraft, damage tolerant structural and mechanical systems, and thermal energy systems.

Shear punch and ball microhardness measurements of 14 MeV neutron irradiation hardening in five metals

NASA Astrophysics Data System (ADS)

Shinohara, K.; Lucas, G. E.; Odette, G. R.

1985-08-01

The irradiation hardening response of five metals irradiated in RTNS-II was investigated using a combination of ball microhardness and shear punch test techniques. The specimens were transmission electron microscopy disks of pure nickel, Ni-5wt%Si, pure iron, solution annealed prime candidate alloy (PCA) for Path A, and 40% cold worked MFE 316 stainless steel. Specimens were irradiated in RTNS-II to fluences in the range 6 × 10 16 to 6 × 10 17 n/cm 2. Only limited ball microhardness data could be obtained because of disk thickness. However, the ball microhardness data obtained were in good agreement with shear punch data. It was found that the pure metals exhibited little hardening after exposure to fluences of ~1 × 10 17 n/cm 2, but Ni-5 Si exhibited significant hardening after 6 × 10 17 n/cm 2. Hardening in PCA was similar to that observed in solution annealed 316 stainless steel; and hardening in 40% cold worked MFE 316 was relatively small after 6 × 10 17 n/cm 2. The Ni-5 Si response may be due to irradiation induced precipitation.

Let's Weigh in on "Deflategate"

NASA Astrophysics Data System (ADS)

Toepker, Terrence

2016-09-01

The September 2015 paper "Bouncing Back from `Deflategate'" is a very interesting article from a physics viewpoint. However, we doubt that the National Football League (NFL) officials will bounce footballs and measure the coefficient of restitution to verify that the footballs remain properly inflated. The release of a few pounds per square inch (psi) from a football seems trivial until one reads about the millions of dollars in suspensions, fines, and legal fees that were accrued. What is a possible solution that the NFL might actually use? Weigh the ball! When a small amount of air is deliberately released, causing a change in pressure, the change in mass can be calculated and measured. Note that the change in mass can be measured without making another pressure measurement. This is important because the reinsertion of the needle of the gauge to make another measurement causes a small inadvertent loss of pressure and mass from the ball.

Application study of the optical biopsy system for small experimental animals

NASA Astrophysics Data System (ADS)

Sato, Hidetoshi; Suzuki, Toshiaki; Morita, Shin-ichi; Maruyama, Atsushi; Shimosegawa, Toru; Matsuura, Yuji; Kanai, Gen'ichi; Ura, Nobuo; Masutani, Koji; Ozaki, Yukihiro

2008-02-01

An optical biopsy system for small experimental animals has been developed. The system includes endoscope probe, portable probe and two kinds of miniaturized Raman probes. The micro Raman probe (MRP) is made of optical fibers and the ball lens hollow optical fiber Raman probe (BHRP) is made of hollow fiber. The former has large focal depth and suitable to measure average spectra of subsurface tissue. The latter has rather small focal depth and it is possible to control focal length by selecting ball lens attached at the probe head. It is suitable to survey materials at the fixed depth in the tissue. The system is applied to study various small animal cancer models, such as esophagus and stomach rat models and subcutaneous mouse models of pancreatic cancers. In the studies of subcutaneous tumor model mouse, it is suggested that protein conformational changes occur in the tumor tissue within few minutes after euthanasia of the mouse. No more change is observed for the following ten minutes. Any alterations in the molecular level are not observed in normal skin, muscle tissues. Since the change completes in such a short time, it is suggested that this phenomenon caused by termination of blood circulation.

Grasping in One-Handed Catching in Relation to Performance

PubMed Central

Cesqui, Benedetta; Russo, Marta; Lacquaniti, Francesco; d’Avella, Andrea

2016-01-01

Catching a flying ball involves bringing the hand to the aimed interception point at the right time, adjusting the hand posture to receive the incoming ball and to absorb the ball momentum, and closing the hand to ensure a stable grip. A small error in any of these actions can lead to a failure in catching the ball. Here we sought to gather new insights on what aspects of the catching movements affect the interceptive performance most. In particular, we wondered whether the errors occurred in bringing the hand to the interception point or in closing the fingers on the ball, and whether these two phases of interception differed between individuals. To this end, we characterized grasping and wrist movement kinematics of eleven participants attempting to catch a ball projected in space with different ball arrival heights and flight durations. The spatial position of the ball and of several markers placed on the participant’s arm were recorded by a motion capture system, the hand joint angles were recorded with an instrumented glove, and several movement features were extracted. All participants were able to intercept the ball trajectory (i.e. to touch the ball) in over 90% of cases, but they differed in the ability to grasp the ball (success rate varied between 2% and 85%). Similar temporal features were observed across individuals when they caught the ball. In particular, all participants adapted their wrist movements under varying temporal and arrival height constraints, they aligned the time of peak hand closing velocity to the time of hand-ball contact, and they maintained the same hand closing duration in the different experimental conditions. These movement features characterized successful trials, and hence allowed to evaluate the possible sources of errors underlying unsuccessful trials. Thus, inter-individual and inter-trial variability in the modulation of each kinematic feature were related to catching performance. We observed that different participants used different solutions to bring the hand to the interception point. In particular the value of the wrist velocity at impact distinguished good from poor catchers. However, each individual showed similar wrist kinematics in grasped and touched trials. We also found that specific grasping features predicted the catching outcome, both on a trial-by-trial basis and across individuals of different performance level. A higher speed of hand closing distinguished touched from grasped trials. A proper triggering of the enclosing phase of the grasping movement and an accurate alignment of the peak of the hand closing speed to the impact event predicted the catching performance of different participants. These results indicate that the control of the grasping movement was the main source of errors affecting catching performance in our experiments. Moreover, these results suggest that distinct temporal and spatial features in the coordination of the grasping movement are related to individual catching abilities. PMID:27392041

A new measurement method of profile tolerance for the LAMOST focal plane

NASA Astrophysics Data System (ADS)

Zhou, Zengxiang; Jin, Yi; Zhai, Chao; Xing, Xiaozheng

2008-07-01

There were a few methods taken in the profile tolerance measurement of the LAMOST Focal Plane Plate. One of the methods was to use CMM (Coordinate Measurement Machine) to measure the points on the small Focal Plane Plate and calculate the points whether or not in the tolerance zone. In this process there are some small shortcomings. The measuring point positions on the Focal Plane Plate are not the actual installation location of the optical fiber positioning system. In order to eliminate these principle errors, a measuring mandrel is inserted into the unit-holes, and the precision for the mandrel with the hole is controlled in the high level. Then measure the center of the precise target ball which is placed on the measuring mandrel by CMM. At last, fit a sphere surface with the measuring center points of the target ball and analyze the profile tolerance of the Focal Plane Plate. This process will be more in line with the actual installation location of the optical fiber positioning system. When use this method to judge the profile tolerance can provide the reference date for maintaining the ultra error unit-holes on the Focal Plane Plate. But when insert the measuring mandrel into the unit hole, there are manufacturing errors in the measuring mandrel, target ball and assembly errors. All these errors will bring the influence in the measurement. In the paper, an impact evaluation assesses the intermediate process with all these errors through experiments. And the experiment results show that there are little influence when use the target ball and the measuring mandrel in the measurement of the profile tolerance. Instead, there are more advantages than many past use of measuring methods.

Non-stationary filtration mode during chemical reactions with the gas phase

NASA Astrophysics Data System (ADS)

Zavialov, Ivan; Konyukhov, Andrey; Negodyaev, Sergey

2015-04-01

An experimental and numerical study of filtration accompanied by chemical reactions between displacing fluid and solid skeleton is considered. Glass balls (400-500 μm in diameter) were placed in 1 cm gap between two glass sheets and were used as model porous medium. The baking soda was added to the glass balls. The 70% solution of acetic acid was used as the displacer. The modeling porous medium was saturated with a mineral oil, and then 70% solution of colored acetic acid was pumped through the medium. The glass balls and a mineral oil have a similar refractive index, so the model porous medium was optically transparent. During the filtration, the gas phase was generated by the chemical reactions between the baking soda and acetic acid, and time-dependent displacement of the chemical reaction front was observed. The front of the chemical reaction was associated with the most intensive gas separation. The front moved, stopped, and then moved again to the area where it had been already. We called this process a secondary oxidation wave. To describe this effect, we added to the balance equations a term associated with the formation and disappearance of phases due to chemical reactions. The equations were supplemented by Darcy's law for multiphase filtration. Nonstationarity front propagation of the chemical reaction in the numerical experiment was observed at Damköhler numbers greater than 100. The mathematical modelling was agreed well with the experimental results.

KEPLER EXOPLANET CANDIDATE HOST STARS ARE PREFERENTIALLY METAL RICH

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

Schlaufman, Kevin C.; Laughlin, Gregory, E-mail: kcs@ucolick.org, E-mail: laughlin@ucolick.org

We find that Kepler exoplanet candidate (EC) host stars are preferentially metal rich, including the low-mass stellar hosts of small-radius ECs. The last observation confirms a tentative hint that there is a correlation between the metallicity of low-mass stars and the presence of low-mass and small-radius exoplanets. In particular, we compare the J-H-g-r color-color distribution of Kepler EC host stars with a control sample of dwarf stars selected from the {approx}150, 000 stars observed during Q1 and Q2 of the Kepler mission but with no detected planets. We find that at J - H = 0.30 characteristic of solar-type stars,more » the average g-r color of stars that host giant ECs is 4{sigma} redder than the average color of the stars in the control sample. At the same J - H color, the average g-r color of solar-type stars that host small-radius ECs is indistinguishable from the average color of the stars in the control sample. In addition, we find that at J - H = 0.62 indicative of late K dwarfs, the average g-r color of stars that host small-radius ECs is 4{sigma} redder than the average color of the stars in the control sample. These offsets are unlikely to be caused by differential reddening, age differences between the two populations, or the presence of giant stars in the control sample. Stellar models suggest that the first color offset is due to a 0.2 dex enhancement in [Fe/H] of the giant EC host population at M{sub *} {approx} 1 M{sub sun}, while Sloan photometry of M 67 and NGC 6791 suggests that the second color offset is due to a similar [Fe/H] enhancement of the small-radius EC host population at M{sub *} {approx} 0.7 M{sub sun}. These correlations are a natural consequence of the core-accretion model of planet formation.« less

Stratus Ocean Reference Station (20 deg S, 85 deg W) Mooring Recovery and Deployment Cruise, R/V Ronald H. Brown Cruise 06-07, October 9-October 27, 2006

DTIC Science & Technology

2007-02-01

SUNWAVE as a viable alternative to organotin, copper , and other more toxic coatings. The Table III.D.3 below shows methods used for coating the buoy hull...trasdu 1.8 m (2 each) Tsunameter S almm chain (3.5 m) Swivel ss , u-d ct, of-aoic 25 mm nylon G.l as ball acoustic flotation teiemetry 1 22 mm nylon...e - Size(s) Manufacturer .... .......... Chain ,Wire Rope- Hardware Flotation Type (G.8.s, Spheres,_etc) Si ze Quantijty Color No. of Flotation

4K Video of Colorful Liquid in Space

NASA Image and Video Library

2015-10-09

Once again, astronauts on the International Space Station dissolved an effervescent tablet in a floating ball of water, and captured images using a camera capable of recording four times the resolution of normal high-definition cameras. The higher resolution images and higher frame rate videos can reveal more information when used on science investigations, giving researchers a valuable new tool aboard the space station. This footage is one of the first of its kind. The cameras are being evaluated for capturing science data and vehicle operations by engineers at NASA's Marshall Space Flight Center in Huntsville, Alabama.

Novel device for male infertility screening with single-ball lens microscope and smartphone.

PubMed

Kobori, Yoshitomo; Pfanner, Peter; Prins, Gail S; Niederberger, Craig

2016-09-01

To investigate the usefulness of a novel semen analysis device consisting of a single-ball lens microscope paired with a state-of-the-art smartphone equipped with a camera. Laboratory investigation. University research laboratory. A total of 50 semen samples obtained from volunteers were analyzed for count, concentration, and motility with an 0.8-mm ball lens and three types of smartphone. Comparisons were made with results obtained with a laboratory-based computer-assisted sperm analysis (CASA) system. None. Sperm concentration; sperm motility. Sperm concentration counted with a ball lens and each smartphone showed a very strong correlation with the CASA results. Likewise, sperm motility calculated with our device showed significant correlations to CASA. If eight spermatozoa or fewer were found on the field of view of an iPhone 6s, the semen specimens were considered to be below the lower reference limit for sperm concentration of World Health Organization 2010 guidelines (15 × 10(6) spermatozoa/mL). The sensitivity was 87.5%, and specificity was 90.9%. Smartphones have great potential to analyze semen because they are portable, contain excellent digital cameras, and can be easily attached to a microscope. A single-ball lens microscope is inexpensive and easy to use for acquiring digital microscopic movies. Given its small size and weight, the device can support testing for male fertility at home or in the field, making it much more convenient and economical than current practice. This single-ball lens microscope provides an easy solution for global users to rapidly screen for male infertility. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Sound Guard

NASA Technical Reports Server (NTRS)

1978-01-01

Lubrication technology originally developed for a series of NASA satellites has produced a commercial product for protecting the sound fidelity of phonograph records. Called Sound Guard, the preservative is a spray-on fluid that deposits a microscopically thin protective coating which reduces friction and prevents the hard diamond stylus from wearing away the softer vinyl material of the disc. It is marketed by the Consumer Products Division of Ball Corporation, Muncie, Indiana. The lubricant technology on which Sound Guard is based originated with NASA's Orbiting Solar Observatory (OSO), an Earth-orbiting satellite designed and built by Ball Brothers Research Corporation, Boulder, Colorado, also a division of Ball Corporation. Ball Brothers engineers found a problem early in the OSO program: known lubricants were unsuitable for use on satellite moving parts that would be exposed to the vacuum of space for several months. So the company conducted research on the properties of materials needed for long life in space and developed new lubricants. They worked successfully on seven OSO flights and attracted considerable attention among other aerospace contractors. Ball Brothers now supplies its "Vac Kote" lubricants and coatings to both aerospace and non-aerospace industries and the company has produced several hundred variations of the original technology. Ball Corporation expanded its product line to include consumer products, of which Sound Guard is one of the most recent. In addition to protecting record grooves, Sound Guard's anti-static quality also retards particle accumulation on the stylus. During comparison study by a leading U.S. electronic laboratory, a record not treated by Sound Guard had to be cleaned after 50 plays and the stylus had collected a considerable number of small vinyl particles. The Sound Guard-treated disc was still clean after 100 plays, as was its stylus.

Clarifying color category border according to color vision

NASA Astrophysics Data System (ADS)

Ichihara, Takumi; Ichihara, Yasuyo G.

2015-01-01

We usually recognize color by two kinds of processes. In the first, the color is recognized continually and a small difference in color is recognized. In the second, the color is recognized discretely. This process recognizes a similar color of a certain range as being in the same color category. The small difference in color is ignored. Recognition by using the color category is important for communication using color. It is known that a color vision defect confuses colors on the confusion locus of color. However, the color category of a color vision defect has not been thoroughly researched. If the color category of the color vision defect is clarified, it will become an important key for color universal design. In this research, we classified color stimuli into four categories to check the shape and the border of the color categories of varied color vision. The experimental result was as follows. The border of protanopia is the following three on the CIE 1931 (x, y) chromaticity diagram: y = -0.3068x + 0.4795, y = -0.1906x + 0.4021, y = -0.2624x + 0.3896. The border of deuteranopia is the following three on the CIE 1931 (x, y) chromaticity diagram: y = -0.7931x + 0.7036, y = -0.718x + 0.5966, y = -0.6667x + 0.5061.

Soccer player recognition by pixel classification in a hybrid color space

NASA Astrophysics Data System (ADS)

Vandenbroucke, Nicolas; Macaire, Ludovic; Postaire, Jack-Gerard

1997-08-01

Soccer is a very popular sport all over the world, Coaches and sport commentators need accurate information about soccer games, especially about the players behavior. These information can be gathered by inspectors who watch the soccer match and report manually the actions of the players involved in the principal phases of the game. Generally, these inspectors focus their attention on the few players standing near the ball and don't report about the motion of all the other players. So it seems desirable to design a system which automatically tracks all the players in real- time. That's why we propose to automatically track each player through the successive color images of the sequences acquired by a fixed color camera. Each player which is present in the image, is modelized by an active contour model or snake. When, during the soccer match, a player is hidden by another, the snakes which track these two players merge. So, it becomes impossible to track the players, except if the snakes are interactively re-initialized. Fortunately, in most cases, the two players don't belong to the same team. That is why we present an algorithm which recognizes the teams of the players by pixels representing the soccer ground which must be withdrawn before considering the players themselves. To eliminate these pixels, the color characteristics of the ground are determined interactively. In a second step, dealing with windows containing only one player of one team, the color features which yield the best discrimination between the two teams are selected. Thanks to these color features, the pixels associated to the players of the two teams form two separated clusters into a color space. In fact, there are many color representation systems and it's interesting to evaluate the features which provide the best separation between the two classes of pixels according to the players soccer suit. Finally, the classification process for image segmentation is based on the three most discriminating color features which define the coordinates of each pixel in an 'hybrid color space.' Thanks to this hybrid color representation, each pixel can be assigned to one of the two classes by a minimum distance classification.

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments.

PubMed

Belenguer, Ana M; Lampronti, Giulio I; Sanders, Jeremy K M

2018-01-23

The equilibrium outcomes of ball mill grinding can dramatically change as a function of even tiny variations in the experimental conditions such as the presence of very small amounts of added solvent. To reproducibly and accurately capture this sensitivity, the experimentalist needs to carefully consider every single factor that can affect the ball mill grinding reaction under investigation, from ensuring the grinding jars are clean and dry before use, to accurately adding the stoichiometry of the starting materials, to validating that the delivery of solvent volume is accurate, to ensuring that the interaction between the solvent and the powder is well understood and, if necessary, a specific soaking time is added to the procedure. Preliminary kinetic studies are essential to determine the necessary milling time to achieve equilibrium. Only then can exquisite phase composition curves be obtained as a function of the solvent concentration under ball mill liquid assisted grinding (LAG). By using strict and careful procedures analogous to the ones here presented, such milling equilibrium curves can be obtained for virtually all milling systems. The system we use to demonstrate these procedures is a disulfide exchange reaction starting from the equimolar mixture of two homodimers to obtain at equilibrium quantitative heterodimer. The latter is formed by ball mill grinding as two different polymorphs, Form A and Form B. The ratio R = [Form B] / ([Form A] + [Form B]) at milling equilibrium depends on the nature and concentration of the solvent in the milling jar.

Coupled analysis of high and low frequency resonant ultrasound spectroscopy: Application to the detection of defects in ceramic balls

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

Deneuville, Francois; Duquennoy, Marc; Ouaftouh, Mohammadi

2009-05-15

A coupled analysis of high and low frequency resonant ultrasound spectroscopy of spheroidal modes is presented in this paper. Experimentally, by using an ultrasonic probe for the excitation (piezoelectric transducer) and a heterodyne optic probe for the receiver (interferometer), it was possible to take spectroscopic measurements of spheroidal vibrations over a large frequency range of 100 kHz-45 MHz in a continuous regime. This wide analysis range enabled variations in velocity due to the presence of defects to be differentiated from the inherent characteristics of the balls and consequently, it offers the possibility of detecting cracks independently of production variations. Thismore » kind of defect is difficult to detect because the C-shaped surface crack is very small and narrow (500x5 {mu}m{sup 2}), and its depth does not exceed 50 {mu}m. The proposed methodology can excite spheroidal vibrations in the ceramic balls and detect such vibrations over a large frequency range. On the one hand, low frequency resonances are used in order to estimate the elastic coefficients of the balls according to various inspection depths. This method has the advantage of providing highly accurate evaluations of the elastic coefficients over a wide frequency range. On the other hand, high frequency vibrations are considered because they are similar to the surface waves propagating in the surface zone of the ceramic balls and consequently can be used to detect C-crack defects.« less

78 FR 33975 - Safety Zone; Flagship Niagara Mariners Ball Fireworks, Presque Isle Bay, Erie, PA

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-06

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Equal-magnitude size-weight illusions experienced within and between object categories.

PubMed

Buckingham, Gavin; Goodale, Melvyn A; White, Justin A; Westwood, David A

2016-01-01

In the size-weight illusion (SWI), small objects feel heavier than larger objects of the same mass. This effect is typically thought to be a consequence of the lifter's expectation that the large object will outweigh the small object, because objects of the same type typically get heavier as they get larger. Here, we show that this perceptual effect can occur across object category, where there are no strong expectations about the correspondence between size and mass. One group of participants lifted same-colored large and small cubes with the same mass as one another, while another group lifted differently-colored large and small cubes with the same mass as one another. The group who lifted the same-colored cubes experienced a robust SWI and initially lifted the large object with more force than the small object. By contrast, the group who lifted the different-colored objects did so with equal initial forces on the first trial, but experienced just as strong an illusion as those who lifted the same-colored objects. These results demonstrate that color cues can selectively influence the application of fingertip force rates while not impacting at all upon the lifter's perception of object weight, highlighting a stark dissociation in how prior information affects perception and action.

Improved Method Being Developed for Surface Enhancement of Metallic Materials

NASA Technical Reports Server (NTRS)

Gabb, Timothy P.; Telesman, Jack; Kantzos, Peter T.

2001-01-01

Surface enhancement methods induce a layer of beneficial residual compressive stress to improve the impact (FOD) resistance and fatigue life of metallic materials. A traditional method of surface enhancement often used is shot peening, in which small steel spheres are repeatedly impinged on metallic surfaces. Shot peening is inexpensive and widely used, but the plastic deformation of 20 to 40 percent imparted by the impacts can be harmful. This plastic deformation can damage the microstructure, severely limiting the ductility and durability of the material near the surface. It has also been shown to promote accelerated relaxation of the beneficial compressive residual stresses at elevated temperatures. Low-plasticity burnishing (LPB) is being developed as an improved method for the surface enhancement of metallic materials. LPB is being investigated as a rapid, inexpensive surface enhancement method under NASA Small Business Innovation Research contracts NAS3-98034 and NAS3-99116, with supporting characterization work at NASA. Previously, roller burnishing had been employed to refine surface finish. This concept was adopted and then optimized as a means of producing a layer of compressive stress of high magnitude and depth, with minimal plastic deformation (ref. 1). A simplified diagram of the developed process is given in the following figure. A single pass of a smooth, free-rolling spherical ball under a normal force deforms the surface of the material in tension, creating a compressive layer of residual stress. The ball is supported in a fluid with sufficient pressure to lift the ball off the surface of the retaining spherical socket. The ball is only in mechanical contact with the surface of the material being burnished and is free to roll on the surface. This apparatus is designed to be mounted in the conventional lathes and vertical mills currently used to machine parts. The process has been successfully applied to nickel-base superalloys by a team from the NASA Glenn Research Center, Lambda Research, and METCUT Research, as supported by the NASA Small Business Innovation Research Phase I and II programs, the Ultra Safe program, and the Ultra- Efficient Engine Technology (UEET) Program.

Estimation of Mechanical Properties of Stainless Steel AISI 410 by Small-Punch Testing (Erickson Test)

NASA Astrophysics Data System (ADS)

Hassan, A.-P.

2014-07-01

The small-punch testing (SPT) method is used for determining the mechanical properties of AISI 410 (0.14% C, 12% Cr) stainless steel. A thin disc-shaped specimen with known mechanical properties is pressed with a small ball until the appearance of cracks in the former. The load - displacement curves are recorded. Computation of the yield strength and fracture energy by the curve obtained and by known formulas shows good convergence with the characteristics obtained by standard testing.

Symmetry breaking, Josephson oscillation and self-trapping in a self-bound three-dimensional quantum ball.

PubMed

Adhikari, S K

2017-11-22

We study spontaneous symmetry breaking (SSB), Josephson oscillation, and self-trapping in a stable, mobile, three-dimensional matter-wave spherical quantum ball self-bound by attractive two-body and repulsive three-body interactions. The SSB is realized by a parity-symmetric (a) one-dimensional (1D) double-well potential or (b) a 1D Gaussian potential, both along the z axis and no potential along the x and y axes. In the presence of each of these potentials, the symmetric ground state dynamically evolves into a doubly-degenerate SSB ground state. If the SSB ground state in the double well, predominantly located in the first well (z > 0), is given a small displacement, the quantum ball oscillates with a self-trapping in the first well. For a medium displacement one encounters an asymmetric Josephson oscillation. The asymmetric oscillation is a consequence of SSB. The study is performed by a variational and a numerical solution of a non-linear mean-field model with 1D parity-symmetric perturbations.

Excitation of ship waves by a submerged object: New solution to the classical problem

NASA Astrophysics Data System (ADS)

Arzhannikov, A. V.; Kotelnikov, I. A.

2016-08-01

We have proposed a new method for solving the problem of ship waves excited on the surface of a nonviscous liquid by a submerged object that moves at a variable speed. As a first application of this method, we have obtained a new solution to the classic problem of ship waves generated by a submerged ball that moves rectilinearly with constant velocity parallel to the equilibrium surface of the liquid. For this example, we have derived asymptotic expressions describing the vertical displacement of the liquid surface in the limit of small and large values of the Froude number. The exact solution is presented in the form of two terms, each of which is reduced to one-dimensional integrals. One term describes the "Bernoulli hump" and another term the "Kelvin wedge." As a second example, we considered vertical oscillation of the submerged ball. In this case, the solution leads to the calculation of one-dimensional integral and describes surface waves propagating from the epicenter above the ball.

Excitation of ship waves by a submerged object: New solution to the classical problem.

PubMed

Arzhannikov, A V; Kotelnikov, I A

2016-08-01

We have proposed a new method for solving the problem of ship waves excited on the surface of a nonviscous liquid by a submerged object that moves at a variable speed. As a first application of this method, we have obtained a new solution to the classic problem of ship waves generated by a submerged ball that moves rectilinearly with constant velocity parallel to the equilibrium surface of the liquid. For this example, we have derived asymptotic expressions describing the vertical displacement of the liquid surface in the limit of small and large values of the Froude number. The exact solution is presented in the form of two terms, each of which is reduced to one-dimensional integrals. One term describes the "Bernoulli hump" and another term the "Kelvin wedge." As a second example, we considered vertical oscillation of the submerged ball. In this case, the solution leads to the calculation of one-dimensional integral and describes surface waves propagating from the epicenter above the ball.

A High-Resolution Measurement of Ball IR Black Paint's Low-Temperature Emissivity

NASA Technical Reports Server (NTRS)

Tuttle, Jim; Canavan, Ed; DiPirro, Mike; Li, Xiaoyi; Franck, Randy; Green, Dan

2011-01-01

High-emissivity paints are commonly used on thermal control system components. The total hemispheric emissivity values of such paints are typically high (nearly 1) at temperatures above about 100 Kelvin, but they drop off steeply at lower temperatures. A precise knowledge of this temperature-dependence is critical to designing passively-cooled components with low operating temperatures. Notable examples are the coatings on thermal radiators used to cool space-flight instruments to temperatures below 40 Kelvin. Past measurements of low-temperature paint emissivity have been challenging, often requiring large thermal chambers and typically producing data with high uncertainties below about 100 Kelvin. We describe a relatively inexpensive method of performing high-resolution emissivity measurements in a small cryostat. We present the results of such a measurement on Ball InfraRed BlackTM(BIRBTM), a proprietary surface coating produced by Ball Aerospace and Technologies Corp (BATC), which is used in spaceflight applications. We also describe a thermal model used in the error analysis.

Phosphatase of regenerating liver-3 is expressed in acute lymphoblastic leukemia and mediates leukemic cell adhesion, migration and drug resistance

PubMed Central

Hjort, Magnus A.; Abdollahi, Pegah; Vandsemb, Esten N.; Fenstad, Mona H.; Lund, Bendik; Slørdahl, Tobias S.; Børset, Magne; Rø, Torstein B.

2018-01-01

Phosphatase of regenerating liver-3 (PRL-3/PTP4A3) is upregulated in multiple cancers, including BCR-ABL1- and ETV6-RUNX-positive acute lymphoblastic leukemia (ALL). With this study, we aim to characterize the biological role of PRL-3 in B cell ALL (B-ALL). Here, we demonstrate that PRL-3 expression at mRNA and protein level was higher in B-ALL cells than in normal cells, as measured by qRT-PCR or flow cytometry. Further, we demonstrate that inhibition of PRL-3 using shRNA or a small molecular inhibitor reduced cell migration towards an SDF-1α gradient in the preB-ALL cell lines Reh and MHH-CALL-4. Knockdown of PRL-3 also reduced cell adhesion towards fibronectin in Reh cells. Mechanistically, PRL-3 mediated SDF-1α stimulated calcium release, and activated focal adhesion kinase (FAK) and Src, important effectors of migration and adhesion. Finally, PRL-3 expression made Reh cells more resistance to cytarabine treatment. In conclusion, the expression level of PRL-3 was higher in B-ALL cells than in normal cells. PRL-3 promoted adhesion, migration and resistance to cytarabine. PRL-3 may represent a novel target in the treatment of B-ALL. PMID:29423065

Space weathering and the color indexes of minor bodies in the outer Solar System

NASA Astrophysics Data System (ADS)

Kaňuchová, Zuzana; Brunetto, Rosario; Melita, Mario; Strazzulla, Giovanni

2012-09-01

The surfaces of small bodies in the outer Solar System are rich in organic compounds and carbonaceous refractories mixed with ices and silicates. As made clear by dedicated laboratory experiments space weathering (e.g. energetic ion bombardment) can produce red colored materials starting from bright and spectrally flat ices. In a classical scenario, the space weathering processes “nurture” alter the small bodies surface spectra but are in competition with resurfacing agents that restore the original colors, and the result of these competing processes continuously modifying the surfaces is supposed to be responsible for the observed spectral variety of those small bodies. However an alternative point of view is that the different colors are due to “nature” i.e. to the different primordial composition of different objects. In this paper we present a model, based on laboratory results, that gives an original contribution to the “nature” vs. “nurture” debate by addressing the case of surfaces showing different fractions of rejuvenated vs. space weathered surface, and calculating the corresponding color variations. We will show how a combination of increasing dose coupled to different resurfacing can reproduce the whole range of observations of small outer Solar System bodies. Here we demonstrate, for the first time that objects having a fully weathered material turn back in the color-color diagrams. At the same time, object with the different ratio of pristine and weathered surface areas lay on specific lines in color-color diagrams, if exposed to the same amount of irradiation.

Do Red and Blue Uniforms Matter in Football and Handball Penalties?

PubMed Central

Krenn, Bjoern; Pernhaupt, Niklas; Handsteiner, Markus

2017-01-01

Past research has revealed ambiguous results on the impact of red uniforms in sports competition. The current study was aimed at analyzing the role of red and blue uniforms in football and handball penalties. Two experiments were conducted using a within subjects design, where participants rated uniform color-manipulated video clips. In the first study, participants (n = 39) watched footage of football players kicking a penalty, whereas in the second study (n = 118) videos of handball penalty takers, handball goalkeepers and football goalkeepers preparing themselves to score/save a penalty were shown. Participants rated player’s/goalkeeper’s level of confidence and the expected position of the ball crossing the goal line in the first experiment and additionally the probability of scoring the penalty against the goalkeepers in the second experiment. The videos stopped at the point where the ball was leaving the foot and hand respectively. Results did not show any beneficial impact of red uniforms. Rather, football players wearing blue were rated to kick the ball higher. The study contradicts any positive effect of red versus blue uniforms in the context of football and handball penalties, which emphasizes the need of searching for potential moderators of color’s impact on human behavior. Key points In two video-based experiments no potential advantage of wearing red versus blue in football and handball penalties for either goalkeepers or penalty takers was found. The roles of contextual variables differing in various sports are discussed as potential moderator of color’s impact on human behavior. PMID:29238258

A theory with consolidation: Linking everything to explain everything

NASA Astrophysics Data System (ADS)

Biraris, Gaurav Shantaram

The paper reports a theory which gives explicit (ontic) understanding of the abstract (epistemic) mechanisms spanning many branches of physics. It results to most modern physics starting from Newtonian physics by abandoning progress in twentieth century. The theory assumes consolidation of points in 4-balls of specific radius in the universe. Thus the 4-balls are fundamental elements of the universe. Analogue of momentum defined as soul vector is assumed to be induced on the 4-balls at the beginning of the universe. Then with progression of local time, collisions happen leading to different rotations of CNs. For such rotations, the consolidation provides centripetal binding. By using general terminologies of force and work, the mass energy mechanism gets revealed. The theory provides explicit interpretation of intrinsic properties of mass, electric charge, color charge, weak charge, spin etc. It also provides explicit understanding of the wave-particle duality & quantum mechanics. Epistemic study of the universe with the consolidation results to conventional quantum theories. Elementary mechanism of the field interactions is evident due to conservation of the soul vectors, and its epistemic expectation results to the gauge theories. The theory predicts that four types of interaction would exist in the universe along with the acceptable relative strengths; it provides fundamental interpretation of the physical forces. Further, it explains the basic mechanisms which can be identified with dark energy & dark matter. It also results to (or explains) entanglement, chirality, excess of matter, 4-component spinor, real-abstract (ontic-epistemic) correspondence etc. The theory is beyond standard model and results to the standard model, relativity, dark energy & dark matter, starting by simple assumptions.

Small-scale Conformity of the Virgo Cluster Galaxies

NASA Astrophysics Data System (ADS)

Lee, Hye-Ran; Lee, Joon Hyeop; Jeong, Hyunjin; Park, Byeong-Gon

2016-06-01

We investigate the small-scale conformity in color between bright galaxies and their faint companions in the Virgo Cluster. Cluster member galaxies are spectroscopically determined using the Extended Virgo Cluster Catalog and the Sloan Digital Sky Survey Data Release 12. We find that the luminosity-weighted mean color of faint galaxies depends on the color of adjacent bright galaxy as well as on the cluster-scale environment (gravitational potential index). From this result for the entire area of the Virgo Cluster, it is not distinguishable whether the small-scale conformity is genuine or if it is artificially produced due to cluster-scale variation of galaxy color. To disentangle this degeneracy, we divide the Virgo Cluster area into three sub-areas so that the cluster-scale environmental dependence is minimized: A1 (central), A2 (intermediate), and A3 (outermost). We find conformity in color between bright galaxies and their faint companions (color-color slope significance S ˜ 2.73σ and correlation coefficient {cc}˜ 0.50) in A2, where the cluster-scale environmental dependence is almost negligible. On the other hand, the conformity is not significant or very marginal (S ˜ 1.75σ and {cc}˜ 0.27) in A1. The conformity is not significant either in A3 (S ˜ 1.59σ and {cc}˜ 0.44), but the sample size is too small in this area. These results are consistent with a scenario in which the small-scale conformity in a cluster is a vestige of infallen groups and these groups lose conformity as they come closer to the cluster center.

Small maritime target detection through false color fusion

NASA Astrophysics Data System (ADS)

Toet, Alexander; Wu, Tirui

2008-04-01

We present an algorithm that produces a fused false color representation of a combined multiband IR and visual imaging system for maritime applications. Multispectral IR imaging techniques are increasingly deployed in maritime operations, to detect floating mines or to find small dinghies and swimmers during search and rescue operations. However, maritime backgrounds usually contain a large amount of clutter that severely hampers the detection of small targets. Our new algorithm deploys the correlation between the target signatures in two different IR frequency bands (3-5 and 8-12 μm) to construct a fused IR image with a reduced amount of clutter. The fused IR image is then combined with a visual image in a false color RGB representation for display to a human operator. The algorithm works as follows. First, both individual IR bands are filtered with a morphological opening top-hat transform to extract small details. Second, a common image is extracted from the two filtered IR bands, and assigned to the red channel of an RGB image. Regions of interest that appear in both IR bands remain in this common image, while most uncorrelated noise details are filtered out. Third, the visual band is assigned to the green channel and, after multiplication with a constant (typically 1.6) also to the blue channel. Fourth, the brightness and colors of this intermediate false color image are renormalized by adjusting its first order statistics to those of a representative reference scene. The result of these four steps is a fused color image, with naturalistic colors (bluish sky and grayish water), in which small targets are clearly visible.

Science of Ball Lightning (Fire Ball)

NASA Astrophysics Data System (ADS)

Ohtsuki, Yoshi-Hiko

1989-08-01

The Table of Contents for the full book PDF is as follows: * Organizing Committee * Preface * Ball Lightning -- The Continuing Challenge * Hungarian Ball Lightning Observations in 1987 * Nature of Ball Lightning in Japan * Phenomenological and Psychological Analysis of 150 Austrian Ball Lightning Reports * Physical Problems and Physical Properties of Ball Lightning * Statistical Analysis of the Ball Lightning Properties * A Fluid-Dynamical Model for Ball Lightning and Bead Lightning * The Lifetime of Hill's Vortex * Electrical and Radiative Properties of Ball Lightning * The Candle Flame as a Model of Ball Lightning * A Model for Ball Lightning * The High-Temperature Physico-Chemical Processes in the Lightning Storm Atmosphere (A Physico-Chemical Model of Ball Lightning) * New Approach to Ball Lightning * A Calculation of Electric Field of Ball Lightning * The Physical Explanation to the UFO over Xinjiang, Northern West China * Electric Reconnection, Critical Ionization Velocity, Ponderomotive Force, and Their Applications to Triggered and Ball Lightning * The PLASMAK™ Configuration and Ball Lightning * Experimental Research on Ball Lightning * Performance of High-Voltage Test Facility Designed for Investigation of Ball Lightning * List of Participants

Ball Screw Actuator Including a Compliant Ball Screw Stop

NASA Technical Reports Server (NTRS)

Wingett, Paul T. (Inventor); Hanlon, Casey (Inventor)

2015-01-01

An actuator includes a ball nut, a ball screw, and a ball screw stop. The ball nut is adapted to receive an input torque and in response rotates and supplies a drive force. The ball screw extends through the ball nut and has a first end and a second end. The ball screw receives the drive force from the ball nut and in response selectively translates between a retract position and a extend position. The ball screw stop is mounted on the ball screw proximate the first end to translate therewith. The ball screw stop engages the ball nut when the ball screw is in the extend position, translates, with compliance, a predetermined distance toward the first end upon engaging the ball nut, and prevents further rotation of the ball screw upon translating the predetermined distance.

Ball Screw Actuator Including a Compliant Ball Screw Stop

NASA Technical Reports Server (NTRS)

Wingett, Paul T. (Inventor); Hanlon, Casey (Inventor)

2017-01-01

An actuator includes a ball nut, a ball screw, and a ball screw stop. The ball nut is adapted to receive an input torque and in response rotates and supplies a drive force. The ball screw extends through the ball nut and has a first end and a second end. The ball screw receives the drive force from the ball nut and in response selectively translates between a retract position and a extend position. The ball screw stop is mounted on the ball screw proximate the first end to translate therewith. The ball screw stop engages the ball nut when the ball screw is in the extend position, translates, with compliance, a predetermined distance toward the first end upon engaging the ball nut, and prevents further rotation of the ball screw upon translating the predetermined distance.

Molecular and Genetic Investigation of Tau in Chronic Traumatic Encephalopthy

DTIC Science & Technology

2016-10-01

Very wide blood vessels, but no gliosis, macrophages, or tangles. 6 Controls Heavy retraction around vessels and high amounts of cell shrinkage...neocortical pyramidal neuron. (B) This neuron contains a mature intracellular tangle. (C) In the white matter, scattered small granular retraction balls

Conical Seat Shut-Off Valve

NASA Technical Reports Server (NTRS)

Farner, Bruce

2013-01-01

A moveable valve for controlling flow of a pressurized working fluid was designed. This valve consists of a hollow, moveable floating piston pressed against a stationary solid seat, and can use the working fluid to seal the valve. This open/closed, novel valve is able to use metal-to-metal seats, without requiring seat sliding action; therefore there are no associated damaging effects. During use, existing standard high-pressure ball valve seats tend to become damaged during rotation of the ball. Additionally, forces acting on the ball and stem create large amounts of friction. The combination of these effects can lead to system failure. In an attempt to reduce damaging effects and seat failures, soft seats in the ball valve have been eliminated; however, the sliding action of the ball across the highly loaded seat still tends to scratch the seat, causing failure. Also, in order to operate, ball valves require the use of large actuators. Positioning the metal-to-metal seats requires more loading, which tends to increase the size of the required actuator, and can also lead to other failures in other areas such as the stem and bearing mechanisms, thus increasing cost and maintenance. This novel non-sliding seat surface valve allows metal-to-metal seats without the damaging effects that can lead to failure, and enables large seating forces without damaging the valve. Additionally, this valve design, even when used with large, high-pressure applications, does not require large conventional valve actuators and the valve stem itself is eliminated. Actuation is achieved with the use of a small, simple solenoid valve. This design also eliminates the need for many seals used with existing ball valve and globe valve designs, which commonly cause failure, too. This, coupled with the elimination of the valve stem and conventional valve actuator, improves valve reliability and seat life. Other mechanical liftoff seats have been designed; however, they have only resulted in increased cost, and incurred other reliability issues. With this novel design, the seat is lifted by simply removing the working fluid pressure that presses it against the seat and no external force is required. By eliminating variables associated with existing ball and globe configurations that can have damaging effects upon a valve, this novel design reduces downtime in rocket engine test schedules and maintenance costs.

Candle Flames in Microgravity Video

NASA Technical Reports Server (NTRS)

1997-01-01

This video of a candle flame burning in space was taken by the Candle Flames in Microgravity (CFM) experiment on the Russian Mir space station. It is actually a composite of still photos from a 35mm camera since the video images were too dim. The images show a hemispherically shaped flame, primarily blue in color, with some yellow early int the flame lifetime. The actual flame is quite dim and difficult to see with the naked eye. Nearly 80 candles were burned in this experiment aboard Mir. NASA scientists have also studied how flames spread in space and how to detect fire in microgravity. Researchers hope that what they learn about fire and combustion from the flame ball experiments will help out here on Earth. Their research could help create things such as better engines for cars and airplanes. Since they use very weak flames, flame balls require little fuel. By studying how this works, engineers may be able to design engines that use far less fuel. In addition, microgravity flame research is an important step in creating new safety precautions for astronauts living in space. By understanding how fire works in space, the astronauts can be better prepared to fight it.

Reach the sky

NASA Astrophysics Data System (ADS)

Mariana Peicuti, Cristina

2017-04-01

I am working as primary teacher at Scoala Gimnaziala Dumbrava,Timis County, Romania & my pupils has 6 to 10 years old. I was&I am a main pillar in my community, always disseminating knowledge and experience to students, other teachers in the school area &Timis County.Astronomy is the must favorite subject of my students from my classes. They are very courious & always come to me with questions about Earth and Sky because Curriculum scientific disciplines provides too little information about Earth and Sky.I need to know more about how to teach space contents into my classes&what competencies can form in elementary school and also to share my experience to the others.As a result of participation at this meeting I want to attract as many students to astronomy,science/STEM disciplines&space technologies, to astronomy topics and exploration of outer space.Schools needs to be prepared for social life needs,new generations needs,on science/space technologies,which are one of the key points for developing the knowledge society.I intend to introduce new scientific activities as part of the existing curriculum.I am passionate about astronomy,I need to know new approaches and new ideas for primary because I think Science is very important in daily life. Here are some developed activities with pupils from K-2 grade levels wich I wish share with colleagues in Viena. Subject: MATHEMATICS. Primary Topic: MEASUREMENT : -+=<> ☼ Rockets by Size. Students cut out,color and sequence paper rockets/Read the information on the International Space Station and rockets/Gather pictures of different types of rockets/Print/cut out/color&laminate rocket drawings/Find objects in the room to put in order by height. ☼ Oil Spot Photometer - Measure the brightness of the sun using cooking oil and a white card. A smear of oil on a white card becomes a powerful tool for comparing the brightness of two light sources, including the sun. ☼ The Sundial & Making Shadows-device to measure time by the sun:make a gnomon pattern/Refer to the latitude table to determine the correct angle to mark- 45°/Place the sundial outdoors,with the gnomon pointing North/Record the outline of the gnomon's shadow and record the time next to it/Repeat this process each hour/See if the students notice a pattern in the movement of the shadow. ☼ Play Dough Planets-To demonstrate the size(volume)differences between Earth,Earth's Moon and Mars through a hands-on activity:Make a play dough ball about the size of a marble(Moon).How many "Moons" it would take to make a ball the size of the Mars or Earth?Students combine 8 of the Moon-size balls to make one "Mars"ball.The students have a Moon and a Mars and after that they combine 50 Moon-size balls,to make"Earth." By second to fourth grade age,students are increasingly able to think about abstractions and different perspectives.They can reflect on their thinking and can consider whether their reasoning follows well from the evidence that they have collected.knowledge.They will be learning that science is a continuing process of seeking answers. "We learn best when we learn from our own experiences."

Recent advances in small molecule OLED-on-silicon microdisplays

NASA Astrophysics Data System (ADS)

Ghosh, Amalkumar P.; Ali, Tariq A.; Khayrullin, Ilyas; Vazan, Fridrich; Prache, Olivier F.; Wacyk, Ihor

2009-08-01

High resolution OLED-on-silicon microdisplay technology is unique and challenging since it requires very small subpixel dimensions (~ 2-5 microns). eMagin's OLED microdisplay is based on white top emitter architecture using small molecule organic materials. The devices are fabricated using high Tg materials. The devices are hermetically sealed with vacuum deposited thin film layers. LCD-type color filters are patterned using photolithography methods to generate primary R, G, B colors. Results of recent improvements in the OLED-on-silicon microdisplay technology, with emphasis on efficiencies, lifetimes, grey scale and CIE color coordinates for SVGA and SXGA resolution microdisplays is presented.

Ball Screw Actuator Including a Stop with an Integral Guide

NASA Technical Reports Server (NTRS)

Wingett, Paul T. (Inventor); Perek, John (Inventor); Geck, Kellan (Inventor)

2015-01-01

An actuator includes a housing assembly, a ball nut, a ball screw, and a ball screw stop. The ball nut is rotationally mounted in the housing assembly, is adapted to receive an input torque, and is configured, upon receipt thereof, to rotate and supply a drive force. The ball screw is mounted within the housing assembly and extends through the ball nut. The ball screw has a first end and a second end, and is coupled to receive the drive force from the ball nut. The ball screw is configured, upon receipt of the drive force, to selectively translate between a stow position and a deploy position. The ball screw stop is mounted on the ball screw to translate therewith and is configured to at selectively engage the housing assembly while the ball screw is translating, and engage the ball nut when the ball screw is in the deploy position.

Ball clay and bentonite deposits of the central and western Gulf of Mexico Coastal Plain, United States

USGS Publications Warehouse

Hosterman, John W.

1984-01-01

The Gulf of Mexico Coastal Plain produces approximately 85 percent of the ball clay used in the United States. The best commercial-grade clay deposits are composed of poorly crystalline kaolinite and small amounts of Md illite and (or) smectite. Sand and silt and iron oxide minerals are virtually absent, but quartz is present in the clay-size fraction. The best grade ball clays are found as lenses limited to the Wilcox Group (Paleocene and lower Eocene) and Claiborne Group (middle Eocene). Reserves of ball clay are sufficient for the present, but because of the lenticular nature of the clay bodies, close-spaced drilling, detailed sampling, mineralogic analyses, and ceramic testing are needed to prove future reserves.Approximately 11 percent of the total bentonite produced in the United States comes from the Gulf Coast region. The commercial-grade bentonites are composed primarily of smectite with little or no Md illite and kaolinite. The nonclay impurities are quartz, feldspar, muscovite, biotite, calcite, dolomite, gypsum, and heulandite. Commercial bentonites occur in the Upper Cretaceous formations in Alabama and Mississippi, in Paleocene formations in Mississippi and Tennessee, and in Eocene and Miocene formations in Texas. The demand for low-swelling bentonite of the Gulf Coastal Plain has not increased along with the demand for swelling bentonite; therefore the reserves are adequate.

Analysis of Space Station Centrifuge Rotor Bearing Systems: A Case Study

NASA Technical Reports Server (NTRS)

Poplawski, Joseph V.; Loewenthal, Stuart H.; Oswald, Fred B.; Zaretsky, Erwin V.; Morales, Wilfredo; Street, Kenneth W., Jr.

2014-01-01

A team of NASA bearing and lubrication experts was assembled to assess the risk for the rolling-element bearings used in the International Space Station (ISS) centrifuge rotor (CR) to seize or otherwise fail to survive for the required 10-year life. The CR was designed by the Japan Aerospace Exploration Agency and their subcontractor, NEC Toshiba Space Systems, Ltd. (NTSpace). The NASA team performed a design audit for the most critical rolling-element bearing systems and reviewed the lubricant selected. There is uncertainty regarding the ability of the Braycote 601 grease (Castrol Limited) to reliably provide the 10-year continuous life required without relubrication of the system. The fatigue life of the Rotor Shaft Assembly (RSA) spring loaded face-to-face mount at a 99-percent probability of survival (L1 life) for the ball bearing set was estimated at 700 million hours and the single ball bearing (Row 3) at 58 million hours. These lives satisfy the mission requirements for fatigue. Rolling-element seizure tests on the RSA and fluid slip joint bearings were found unlikely to stop the centrifuge, which can cause damage to the ISS structure. The spin motor encoder duplex angular-contact ball bearings have a hard preload and a large number of small balls have the highest risk of failure. These bearings were not tested for seizure even though they are less tolerant to debris or internal clearance reductions.

Some of the ball lightning observations could be phosphenes induced by energetic radiation from thunderstorms and lightning

NASA Astrophysics Data System (ADS)

Cooray, G. K.; Cooray, G. V.; Dwyer, J. R.

2011-12-01

Ball Lightning was seen and described since antiquity and recorded in many places. However, so far no one has managed to generate them in the laboratory. It is possible that many different phenomena are grouped together and categorized simply as ball lightning. One such phenomenon could be the phosphenes induced in humans by energetic radiation and particles from lightning and thunderstorms. A phosphene is a visual sensation that is characterized by perceiving luminous phenomena without light entering the eye. Phosphenes are generated when electrical signals are created in the retina or the optical nerve by other means in the absence of light stimuli. The fact that energetic radiation produced by radium can give rise to phosphenes was first noted by Giesel in 1899 [1]. A resurge of studies related to the creation of phosphenes by energetic radiation took place after the reports of phosphenes observed in space by Apollo astronauts and first reported by Buzz Aldrin after the Apollo 11 flight to the moon in 1969 [2]. The shapes of the phosphenes observed by astronauts were either rods, comet shaped, or comprised of a single dot, several dots or blobs. The colors were mostly white, but some had been colored yellow, orange, blue, green or red. The majority of the astronauts had perceived some kind of motion in association with the phosphenes. Most of the time, they were moving horizontally (from the periphery of the vision to the center) and sometimes diagonally, but never vertically. Subsequent studies conducted in space and ground confirmed the creation of phosphenes by energetic radiation. From these studies the threshold energy dissipation in the eye tissue necessary for phosphenes induction was estimated to be 10 MeV/cm. In the present study a quantitative analysis of the energetic radiation generated in the form of X-rays, Gamma rays and relativistic electrons by thunderstorms and lightning was made to investigate whether this radiation is strong enough to induce phosphenes. The study shows that: (i) X-rays and relativistic electrons generated by the lightning leaders are strong enough to induce phosphenes in a person located indoors during a direct lightning strike to a building. (ii) Strong gamma ray busts at ground level produced by thunderstorms could release sufficient energy in the eye to induce phosphenes. (iii) If an air plane encounters the source of an ongoing gamma ray burst in a cloud, the energetic electrons penetrating the airplane during the encounter is strong enough to induce phosphenes in the passengers. It is suggested that some of the ball lightning observations are phosphenes induced by energetic radiation from thunderstorms and lightning. [1] Lipetz, L. E. (1955), The X-ray and radium phosphenes, British Journal of Ophthalmology, 39, pp. 577-598. [2] Fuglesang, C. (2007), Using the human eye to image space radiation or the history and status of the light flash phenomena, Nuclear Instruments and Physics Research A, vol. 580, pp. 861 - 865.

The "Collisions Cube" Molecular Dynamics Simulator.

ERIC Educational Resources Information Center

Nash, John J.; Smith, Paul E.

1995-01-01

Describes a molecular dynamics simulator that employs ping-pong balls as the atoms or molecules and is suitable for either large lecture halls or small classrooms. Discusses its use in illustrating many of the fundamental concepts related to molecular motion and dynamics and providing a three-dimensional perspective of molecular motion. (JRH)

Toxic-Waste Disposal by Drain-in-Furnace Technique

NASA Technical Reports Server (NTRS)

Compton, L. E.; Stephens, J. B.; Moynihan, P. I.; Houseman, J.; Kalvinskas, J. J.

1986-01-01

Compact furnace moved from site to site. Toxic industrial waste destroyed using furnace concept developed for disposal of toxic munitions. Toxic waste drained into furnace where incinerated immediately. In furnace toxic agent rapidly drained and destroyed in small combustion chamber between upper and lower layers of hot ceramic balls

Stripping the Sheath From Stranded Cables

NASA Technical Reports Server (NTRS)

Prisk, A. L.; Rotta, J. W.

1985-01-01

Device similar to tubing cutter removes tough plastic cover. Insulation stripper is 3 in. (7.6 cm) long and 1.5 (3.8 cm) in diameter. Two rollers are small-diameter bearings. Cutter blade journaled for rotation between pair of similar bearings. Bearings either pin or ball types of suitable dimensions.

Hard particle effect on surface generation in nano-cutting

NASA Astrophysics Data System (ADS)

Xu, Feifei; Fang, Fengzhou; Zhang, Xiaodong

2017-12-01

The influence of the hard particle on the surface generation, plastic deformation and processing forces in nano-cutting of aluminum is investigated by means of molecular dynamics simulations. In this investigation, a hard particle which is simplified as a diamond ball is embedded under the free surface of workpiece with different depths. The influence of the position of the hard ball on the surface generation and other material removal mechanism, such as the movement of the ball under the action of cutting tool edge, is revealed. The results show that when the hard particle is removed, only a small shallow pit is left on the machined surface. Otherwise, it is pressed down to the subsurface of the workpiece left larger and deeper pit on the generated surface. Besides that, the hard particle in the workpiece would increase the processing force when the cutting tool edge or the plastic carriers interact with the hard particle. It is helpful to optimize the cutting parameters and material properties for obtaining better surface quality in nano-cutting of composites or other materials with micro/nanoscale hard particles in it.

A new family of low cost momentum/reaction wheels

NASA Astrophysics Data System (ADS)

Bialke, Bill

In order to satisfy the tight budgets and stringent power requirements of small and medium sized satellites, a new series of momentum/reaction wheels has been developed by ITHACO, Inc. The T-WHEEL integrates state-of-the-art ball bearing technology with flight-proven materials and conventional fabrication techniques to produce a reliable and manufacturable wheel assembly. Maximum performance is attained by using an optimized ball bearing suspension system and an ironless armature brushless dc motor for low power dissipation and minimum weight. In addition to summaries of the tradeoff studies performed, the results of the development effort include the application of a low vapor pressure synthetic hydrocarbon lubricant in the ball bearing suspension system, and performance data from the ironless armature brushless dc motor and driver. The original 4 N-m-s version (Type A) has been enlarged to increase the momentum storage capacity to 19.5 N-m-s (Type B), using the same suspension system and design baseline. A 68 N-m-s version is currently under development to broaden the product family.

Acoustic Attraction

NASA Astrophysics Data System (ADS)

Oviatt, Eric; Patsiaouris, Konstantinos; Denardo, Bruce

2009-11-01

A sound source of finite size produces a diverging traveling wave in an unbounded fluid. A rigid body that is small compared to the wavelength experiences an attractive radiation force (toward the source). An attractive force is also exerted on the fluid itself. The effect can be demonstrated with a styrofoam ball suspended near a loudspeaker that is producing sound of high amplitude and low frequency (for example, 100 Hz). The behavior can be understood and roughly calculated as a time-averaged Bernoulli effect. A rigorous scattering calculation yields a radiation force that is within a factor of two of the Bernoulli result. For a spherical wave, the force decreases as the inverse fifth power of the distance from the source. Applications of the phenomenon include ultrasonic filtration of liquids and the growth of supermassive black holes that emit sound waves in a surrounding plasma. An experiment is being conducted in an anechoic chamber with a 1-inch diameter aluminum ball that is suspended from an analytical balance. Directly below the ball is a baffled loudspeaker that exerts an attractive force that is measured by the balance.

Relaxation Method for Navier-Stokes Equation

NASA Astrophysics Data System (ADS)

de Oliveira, P. M. C.

2012-04-01

The motivation for this work was a simple experiment [P. M. C. de Oliveira, S. Moss de Oliveira, F. A. Pereira and J. C. Sartorelli, preprint (2010), arXiv:1005.4086], where a little polystyrene ball is released falling in air. The interesting observation is a speed breaking. After an initial nearly linear time-dependence, the ball speed reaches a maximum value. After this, the speed finally decreases until its final, limit value. The provided explanation is related to the so-called von Kármán street of vortices successively formed behind the falling ball. After completely formed, the whole street extends for some hundred diameters. However, before a certain transient time needed to reach this steady-state, the street is shorter and the drag force is relatively reduced. Thus, at the beginning of the fall, a small and light ball may reach a speed superior to the sustainable steady-state value. Besides the real experiment, the numerical simulation of a related theoretical problem is also performed. A cylinder (instead of a 3D ball, thus reducing the effective dimension to 2) is positioned at rest inside a wind tunnel initially switched off. Suddenly, at t = 0 it is switched on with a constant and uniform wind velocity ěc{V} far from the cylinder and perpendicular to it. This is the first boundary condition. The second is the cylinder surface, where the wind velocity is null. In between these two boundaries, the velocity field is determined by solving the Navier-Stokes equation, as a function of time. For that, the initial condition is taken as the known Stokes laminar limit V → 0, since initially the tunnel is switched off. The numerical method adopted in this task is the object of the current text.

Observations of Spacecraft Bearing Lubricant Redistribution Based on Thermal Conductance Measurements

NASA Technical Reports Server (NTRS)

Takeuchi, Yoshimi R.; Frantz, Peter P.; Hilton, Michael R.

2014-01-01

The performance and life of precision ball bearings are critically dependent on maintaining a quantity of oil at the ball/race interface that is sufficient to support a robust protective film. In space applications, where parched conditions are intentionally the norm, harsh operating conditions can displace the small reserves of oil, resulting in reduced film thickness and premature wear. In the past, these effects have proven difficult to model or to measure experimentally. This paper describes a study addressing this challenge, where bearing thermal conductance measurements are employed to infer changes in lubricant quantity at the critical rolling interfaces. In the first part of the paper, we explain how the lubricant's presence and its quantity impacts bearing thermal conductance measurements. For a stationary bearing, we show that conductance is directly related to the lubricant quantity in the ball/race contacts. Hence, aspects of bearing performance related to oil quantity can be understood and insights improved with thermal conductance data. For a moving bearing, a different mechanism of heat transfer dominates and is dependent on lubricant film thickness on the ball. In the second part of the report, we discuss lubricant quantity observations based on bearing thermal conductance measurements. Lubricant quantity, and thus bearing thermal conductance, depends on various initial and operating conditions and is impacted further by the run-in process. A significant effect of maximum run-in speed was also observed, with less oil remaining after obtaining higher speeds. Finally, we show that some of the lubricant that is displaced between the ball and race during run-in operation can be recovered during rest, and we measure the rate of recovery for one example.

A Ball Lightning Model as a Possible Explanation of Recently Reported Cavity Lights

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

Fryberger, David; /SLAC

The salient features of cavity lights, in particular, mobile luminous objects (MLO's), as have been experimentally observed in superconducting accelerator cavities, are summarized. A model based upon standard electromagnetic interactions between a small particle and the 1.5 GHz cavity excitation field is described. This model can explain some features of these data, in particular, the existence of particle orbits without wall contact. While this result is an important success for the model, it is detailed why the model as it stands is incomplete. It is argued that no avenues for a suitable extension of the model through established physics appearmore » evident, which motivates an investigation of a model based upon a more exotic object, ball lightning. As discussed, further motivation derives from the fact that there are significant similarities in many of the qualitative features of ball lightning and MLO's, even though they appear in quite different circumstances and differ in scale by orders of magnitude. The ball lightning model, which incorporates electromagnetic charges and currents, is based on a symmetrized set of Maxwell's equations in which the electromagnetic sources and fields are characterized by a process called dyality rotation. It is shown that a consistent mathematical description of dyality rotation as a physical process can be achieved by adding suitable (phenomenological) current terms to supplement the usual current terms in the symmetrized Maxwell's equations. These currents, which enable the conservation of electric and magnetic charge, are called vacuum currents. It is shown that the proposed ball lightning model offers a good qualitative explanation of the perplexing aspects of the MLO data. Avenues for further study are indicated.« less

Wounding potential of 4.4-mm (.173) caliber steel ball projectiles.

PubMed

Kamphausen, Thomas; Janßen, Katharina; Banaschak, Sibylle; Rothschild, Markus Alexander

2018-03-06

From time to time, severe or fatal injuries caused by small caliber air rifle projectiles are seen. In forensic sciences, the theoretical wounding potential of these weapons and projectiles is widely known. Usually, shots against the skull were reported and, in these cases, penetrating the eyes or thin bone layers of the temporal region. Amongst a huge number of different projectiles available for air guns, sub-caliber 4.4-mm (.173) caliber steel ball projectiles were used in an unusual suicide case. This case led to fundamental questions concerning wound ballistics. An 82-year-old man shot once against his right temporal region and twice into his mouth with a 4.5-mm (.177) caliber air rifle. Because of the exceptionally deep penetration of the base of the skull and the use of spherical-shaped sub-caliber air rifle projectiles, terminal ballistic features were analyzed and compared to results published in forensic literature. Test shots using the same weapon and similar projectiles were fired into ballistic gelatin to measure and calculate basic wound ballistic variables of cal. 4.4-mm (.173) steel balls. In comparison, further test shots with cal. 4.5-mm (.177) steel balls BB (ball bearing), flat-headed and pointed air rifle pellets ("diabolos") were carried out. The theoretical penetration depth in solid bone was calculated with 36.4 mm, and test shots in gelatin from hard contact produced an on-average wound track of 120 mm underlining the potential wounding effect. Furthermore, spherical projectiles could roll back and forth within the barrel, and an air cushion between projectile and breechblock can reduce muzzle velocity by more than half, explaining the retained missile in the temporal region.

Magnetically driven cold valve for 4He

NASA Astrophysics Data System (ADS)

Bueno, J.; Blaauwgeers, R.; Partapsing, R.; Taminiau, I.; Jochemsen, R.

2006-08-01

We have designed a low temperature valve for liquid helium, which uses a magnetic field gradient and a permanent magnet to close. For closing, it presses a small ruby ball onto a Torlon seat. We present a small valve that is easy to build and easily controlled via two wires. It has a fast response, reliable, and has the advantage that there is no dead volume change on closing and no additional helium line is required to operate.

To believe the past or to trust the future

NASA Astrophysics Data System (ADS)

Jin, Fengtao; Zhou, Zhaoyan

2012-01-01

A small ball rolls down from a quarter-circle to a frictionless plane. What will be the magnitude of the normal force when the ball arrives at the tangent point of the circle and the plane? According to the centripetal force formula, the normal force will be 3mg when the curvature radius of the circle is considered, but will be mg instead when the curvature radius of the plane is considered. Which one is the correct answer? The difficulty is that Newton's second law requires the second time derivative of displacement to be continuous; however, this condition is not fulfilled at the tangent point. In this paper we will discuss several possible solutions to this problem in detail.

Measurements of drag and lift on smooth balls in flight

NASA Astrophysics Data System (ADS)

Cross, Rod; Lindsey, Crawford

2017-07-01

Measurements are presented on the drag and lift coefficients for three relatively smooth balls launched in air and tracked with two cameras separated horizontally by 6.4 m. The ball spin was varied in order to investigate whether the Magnus force would increase or decrease when the ball spin was increased. For one ball, the Magnus force increased. For another ball, the Magnus force decreased almost to zero after reaching a maximum. For the third ball, the Magnus force was negative at low ball spins and positive at high ball spins. For one of the balls, the ball spin increased with time as it travelled through the air.

21 CFR 73.170 - Grape skin extract (enocianina).

Code of Federal Regulations, 2012 CFR

2012-04-01

... LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.170 Grape skin extract (enocianina). (a... removed. A small amount of sulphur dioxide may be present. (2) Color additive mixtures for food use made... suitable in color additive mixtures for coloring foods. (b) Specifications. Grape skin extract (enocianina...

21 CFR 73.170 - Grape skin extract (enocianina).

Code of Federal Regulations, 2014 CFR

2014-04-01

... LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.170 Grape skin extract (enocianina). (a... removed. A small amount of sulphur dioxide may be present. (2) Color additive mixtures for food use made... suitable in color additive mixtures for coloring foods. (b) Specifications. Grape skin extract (enocianina...

21 CFR 73.170 - Grape skin extract (enocianina).

Code of Federal Regulations, 2013 CFR

2013-04-01

... LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.170 Grape skin extract (enocianina). (a... removed. A small amount of sulphur dioxide may be present. (2) Color additive mixtures for food use made... suitable in color additive mixtures for coloring foods. (b) Specifications. Grape skin extract (enocianina...

21 CFR 73.170 - Grape skin extract (enocianina).

Code of Federal Regulations, 2011 CFR

2011-04-01

... LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.170 Grape skin extract (enocianina). (a... removed. A small amount of sulphur dioxide may be present. (2) Color additive mixtures for food use made... suitable in color additive mixtures for coloring foods. (b) Specifications. Grape skin extract (enocianina...

21 CFR 73.170 - Grape skin extract (enocianina).

Code of Federal Regulations, 2010 CFR

2010-04-01

... LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.170 Grape skin extract (enocianina). (a... removed. A small amount of sulphur dioxide may be present. (2) Color additive mixtures for food use made... suitable in color additive mixtures for coloring foods. (b) Specifications. Grape skin extract (enocianina...

Schaeberle Crater - False Color

NASA Image and Video Library

2015-01-26

The THEMIS VIS camera contains 5 filters. The data from different filters can create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the floor of Schaeberle Crater, including small dunes.

Nanofiltration Membranes for Removal of Color and Pathogens in Small Public Drinking Water Sources

EPA Science Inventory

Small public water supplies that use surface water as a source for drinking water are frequently faced with elevated levels of color and natural organic matter (NOM) that are precursors for chlorinated disinfection byproduct (DBP) formation. Nanofiltration (NF) systems can preve...

Capen Crater - False Color

NASA Image and Video Library

2015-01-21

The THEMIS VIS camera contains 5 filters. The data from different filters can create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows small dunes of the floor of Capen Crater in Terra Sabea.

Effect of soccer shoe upper on ball behaviour in curve kicks

PubMed Central

Ishii, Hideyuki; Sakurai, Yoshihisa; Maruyama, Takeo

2014-01-01

New soccer shoes have been developed by considering various concepts related to kicking, such as curving a soccer ball. However, the effects of shoes on ball behaviour remain unclear. In this study, by using a finite element simulation, we investigated the factors that affect ball behaviour immediately after impact in a curve kick. Five experienced male university soccer players performed one curve kick. We developed a finite element model of the foot and ball and evaluated the validity of the model by comparing the finite element results for the ball behaviour immediately after impact with the experimental results. The launch angle, ball velocity, and ball rotation in the finite element analysis were all in general agreement with the experimental results. Using the validated finite element model, we simulated the ball behaviour. The simulation results indicated that the larger the foot velocity immediately before impact, the larger the ball velocity and ball rotation. Furthermore, the Young's modulus of the shoe upper and the coefficient of friction between the shoe upper and the ball had little effect on the launch angle, ball velocity, and ball rotation. The results of this study suggest that the shoe upper does not significantly influence ball behaviour. PMID:25266788

Novel mathematical model to estimate ball impact force in soccer.

PubMed

Iga, Takahito; Nunome, Hiroyuki; Sano, Shinya; Sato, Nahoko; Ikegami, Yasuo

2017-11-22

To assess ball impact force during soccer kicking is important to quantify from both performance and chronic injury prevention perspectives. We aimed to verify the appropriateness of previous models used to estimate ball impact force and to propose an improved model to better capture the time history of ball impact force. A soccer ball was fired directly onto a force platform (10 kHz) at five realistic kicking ball velocities and ball behaviour was captured by a high-speed camera (5,000 Hz). The time history of ball impact force was estimated using three existing models and two new models. A new mathematical model that took into account a rapid change in ball surface area and heterogeneous ball deformation showed a distinctive advantage to estimate the peak forces and its occurrence times and to reproduce time history of ball impact forces more precisely, thereby reinforcing the possible mechanics of 'footballer's ankle'. Ball impact time was also systematically shortened when ball velocity increases in contrast to practical understanding for producing faster ball velocity, however, the aspect of ball contact time must be considered carefully from practical point of view.

Effect of soccer shoe upper on ball behaviour in curve kicks

NASA Astrophysics Data System (ADS)

Ishii, Hideyuki; Sakurai, Yoshihisa; Maruyama, Takeo

2014-08-01

New soccer shoes have been developed by considering various concepts related to kicking, such as curving a soccer ball. However, the effects of shoes on ball behaviour remain unclear. In this study, by using a finite element simulation, we investigated the factors that affect ball behaviour immediately after impact in a curve kick. Five experienced male university soccer players performed one curve kick. We developed a finite element model of the foot and ball and evaluated the validity of the model by comparing the finite element results for the ball behaviour immediately after impact with the experimental results. The launch angle, ball velocity, and ball rotation in the finite element analysis were all in general agreement with the experimental results. Using the validated finite element model, we simulated the ball behaviour. The simulation results indicated that the larger the foot velocity immediately before impact, the larger the ball velocity and ball rotation. Furthermore, the Young's modulus of the shoe upper and the coefficient of friction between the shoe upper and the ball had little effect on the launch angle, ball velocity, and ball rotation. The results of this study suggest that the shoe upper does not significantly influence ball behaviour.

Motion on Cycloid Paths: A Project

ERIC Educational Resources Information Center

Gluck, P.

2010-01-01

This article reports a high school laboratory project whose theme is the motion of a small ball on cycloidal tracks. Models were built both of a brachistochrone and of a Huygens pendulum clock whose bob is constrained to move on a cycloidal path. Photogates and a data acquisition system were employed in order to investigate experimentally the…

Visualization of Kepler's Laws of Planetary Motion

ERIC Educational Resources Information Center

Lu, Meishu; Su, Jun; Wang, Weiguo; Lu, Jianlong

2017-01-01

For this article, we use a 3D printer to print a surface similar to universal gravitation for demonstrating and investigating Kepler's laws of planetary motion describing the motion of a small ball on the surface. This novel experimental method allows Kepler's laws of planetary motion to be visualized and will contribute to improving the…

BILLIARDS: Baseline Instrumented Lithology Lander, Inspector and Asteroid Redirection Demonstration System

NASA Technical Reports Server (NTRS)

Marcus, Matthew; Sloane, Joshua; Ortiz, Oliver; Barbee, Brent

2015-01-01

BILLIARDS Baseline Instrumented Lithology Lander, Inspector, and Asteroid Redirection Demonstration System Proposed demonstration mission for Billiard-Ball concept Select asteroid pair with natural close approach to minimize cost and complexity Primary Objectives Rendezvous with a small (10m), near Earth (alpha) asteroid Maneuver the alpha asteroid to a collision with a 100m (beta) asteroid Produce a detectable deflection or disruption of the beta asteroid Secondary objectives Contribute knowledge of asteroid composition and characteristics Contribute knowledge of small-body formation Opportunity for international collaboration

Manipulator for rotating and examining small spheres

DOEpatents

Weinstein, Berthold W. [Livermore, CA; Willenborg, David L. [Livermore, CA

1980-02-12

A manipulator which provides fast, accurate rotational positioning of a small sphere, such as an inertial confinement fusion target, which allows inspecting of the entire surface of the sphere. The sphere is held between two flat, flexible tips which move equal amounts in opposite directions. This provides rolling of the ball about two orthogonal axes without any overall translation. The manipulator may be controlled, for example, by an x- and y-axis driven controlled by a mini-computer which can be programmed to generate any desired scan pattern.

Combines Attitude Control and Energy Storage for Small Satellites using Variable Speed Control Moment Gyroscopes

DTIC Science & Technology

2008-06-24

CMG torque amplification property in which a small amount of CMG gimbal motor input torque results in a relatively large slewing torque gives it a... properties these actuators provide [74–77]. 2.1.3 Magnetic Levitation and Bearing Technology Magnetic bearings for flywheel rotor suspension has a rich...2.1: Example of Magnetic and Ball Bearing Properties [21] Bearing ID OD Height Radial Static Max Speed (mm) (mm) (mm) Capacity(N) (RPM) MB-R-25-205 25

75 FR 34688 - Ball Bearings and Parts Thereof from France: Final Results of Changed-Circumstances Review

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-18

...: antifriction balls, ball bearings with integral shafts, ball bearings (including radial ball bearings) and... thereof (inner race, outer race, cage, rollers, balls, seals, shields, etc.) outlined above with certain...

78 FR 29702 - Ball Bearings and Parts Thereof From Germany: Final Results of Antidumping Duty Administrative...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-21

... balls, ball bearings with integral shafts, ball bearings (including radial ball bearings) and parts... all the subject bearings and parts thereof (inner race, outer race, cage, rollers, balls, seals...

Dual load path ball screw with rod end swivel

NASA Technical Reports Server (NTRS)

Wngett, Paul (Inventor)

2002-01-01

A dual drive ball has a ball screw shaft coupled at one end to a gear train and coupled at the other end to a ball screw nut. The ball screw shaft and ball screw nut are connected through complementary helical grooves filled with ball bearing balls. The outer surface of the ball screw nut is plined and can be driven by a second gear train. An output tube is coupled at one end to the ball screw nut and at its opposite end has a connector portion with a groove on its inner surface. A rod end has a coupling member for coupling to a surface to be actuated and a shaft portion with a groobe on its outer surface. This shaft portion is received with in the outputtube portion and the corresponding grooves are coupled through the use of a plurality of ball bearing balls.

The biological basis of a universal constraint on color naming: cone contrasts and the two-way categorization of colors.

PubMed

Xiao, Youping; Kavanau, Christopher; Bertin, Lauren; Kaplan, Ehud

2011-01-01

Many studies have provided evidence for the existence of universal constraints on color categorization or naming in various languages, but the biological basis of these constraints is unknown. A recent study of the pattern of color categorization across numerous languages has suggested that these patterns tend to avoid straddling a region in color space at or near the border between the English composite categories of "warm" and "cool". This fault line in color space represents a fundamental constraint on color naming. Here we report that the two-way categorization along the fault line is correlated with the sign of the L- versus M-cone contrast of a stimulus color. Moreover, we found that the sign of the L-M cone contrast also accounted for the two-way clustering of the spatially distributed neural responses in small regions of the macaque primary visual cortex, visualized with optical imaging. These small regions correspond to the hue maps, where our previous study found a spatially organized representation of stimulus hue. Altogether, these results establish a direct link between a universal constraint on color naming and the cone-specific information that is represented in the primate early visual system.

[Luminescence properties of white LED blue light conversion materials].

PubMed

Hao, Hai-tao; Zhou, He-feng; Liang, Jian; Liu, Xu-guang; Xu, Bing-she

2007-02-01

Using rare earth oxides as raw materials, yttrium aluminum garnets activated by cerium and gadolinium ions were prepared by high energy ball milling and solid-state reaction at 1300 degrees C. The crystal structures of the products were studied by XRD, and the luminescence characteristics of Ce ion and the influence of Gd ion were studied by emission and excitation spectra. The results indicated that the products were yttrium aluminum garnet crystals of cubic system, and they were excited by blue light chips effectively. The emission peak of phosphors could change among 530-560 nm by adjusting the mole density of doping ions. The red shift of emission spectra could be interpreted with the configuration coordination figure. White LEDs were fabricated by phosphor conversion. When electric current is 20 mA, and the working voltage is 3.5 V, the white light LED chromaticity coordinates are x=0.310 and y=0.323, the lumen efficiency is 26.131 m x W(-1), the color rendering index is 81.8, and the color temperature is 6605 K.

Ball Machine Usage in Tennis: Movement Initiation and Swing Timing While Returning Balls from a Ball Machine and from a Real Server

PubMed Central

Carboch, Jan; Süss, Vladimir; Kocib, Tomas

2014-01-01

Practicing with the use of a ball machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a ball projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a ball machine or by a real server). Receivers’ movements were measured on a tennis court. In spite of using a serving ball speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a ball machine and serves received from a real server. Players had shorter movement initiation when they faced a ball machine. Backswing duration was longer for the group using a ball machine. That demonstrates different movement timing of tennis returns when players face a ball machine. Use of ball machines in tennis practice should be limited as it may disrupt stroke timing. Key points Players have shorter initial move time when they are facing the ball machine. Using the ball machine results in different swing timing and movement coordination. The use of the ball machine should be limited. PMID:24790483

Ball machine usage in tennis: movement initiation and swing timing while returning balls from a ball machine and from a real server.

PubMed

Carboch, Jan; Süss, Vladimir; Kocib, Tomas

2014-05-01

Practicing with the use of a ball machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a ball projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a ball machine or by a real server). Receivers' movements were measured on a tennis court. In spite of using a serving ball speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a ball machine and serves received from a real server. Players had shorter movement initiation when they faced a ball machine. Backswing duration was longer for the group using a ball machine. That demonstrates different movement timing of tennis returns when players face a ball machine. Use of ball machines in tennis practice should be limited as it may disrupt stroke timing. Key pointsPlayers have shorter initial move time when they are facing the ball machine.Using the ball machine results in different swing timing and movement coordination.The use of the ball machine should be limited.

RCSD1-ABL1 Translocation Associated with IKZF1 Gene Deletion in B-Cell Acute Lymphoblastic Leukemia.

PubMed

Kamran, Shawana; Raca, Gordana; Nazir, Kamran

2015-01-01

The RCSD1 gene has recently been identified as a novel gene fusion partner of the ABL1 gene in cases of B-cell Acute Lymphoblastic Leukemia (B-ALL). The RCSD1 gene is located at 1q23 and ABL1 is located at 9q34, so that the RCSD1-ABL1 fusion typically arises through a rare reciprocal translocation t(1;9)(q23;q34). Only a small number of RCSD1-ABL1 positive cases of B-ALL have been described in the literature, and the full spectrum of clinical, morphological, immunophenotypic, and molecular features associated with this genetic abnormality has not been defined. We describe extensive genetic characterization of a case of B-ALL with RCSD1-ABL1 fusion, by using conventional cytogenetic analysis, Fluorescence In Situ Hybridization (FISH) studies, and Chromosomal Microarray Analysis (CMA). The use of CMA resulted in detection of an approximately 70 kb deletion at 7p12.2, which caused a disruption of the IKZF1 gene. Deletions and mutations of IKZF1 are recurring abnormalities in B-ALL and are associated with a poor prognosis. Our findings highlight the association of the deletion of IKZF1 gene with the t(1;9)(q24;q34) and illustrate the importance of comprehensive cytogenetic and molecular evaluation for accurate prediction of prognosis in patients with B-cell ALL.

RCSD1-ABL1 Translocation Associated with IKZF1 Gene Deletion in B-Cell Acute Lymphoblastic Leukemia

PubMed Central

Kamran, Shawana; Nazir, Kamran

2015-01-01

The RCSD1 gene has recently been identified as a novel gene fusion partner of the ABL1 gene in cases of B-cell Acute Lymphoblastic Leukemia (B-ALL). The RCSD1 gene is located at 1q23 and ABL1 is located at 9q34, so that the RCSD1-ABL1 fusion typically arises through a rare reciprocal translocation t(1;9)(q23;q34). Only a small number of RCSD1-ABL1 positive cases of B-ALL have been described in the literature, and the full spectrum of clinical, morphological, immunophenotypic, and molecular features associated with this genetic abnormality has not been defined. We describe extensive genetic characterization of a case of B-ALL with RCSD1-ABL1 fusion, by using conventional cytogenetic analysis, Fluorescence In Situ Hybridization (FISH) studies, and Chromosomal Microarray Analysis (CMA). The use of CMA resulted in detection of an approximately 70 kb deletion at 7p12.2, which caused a disruption of the IKZF1 gene. Deletions and mutations of IKZF1 are recurring abnormalities in B-ALL and are associated with a poor prognosis. Our findings highlight the association of the deletion of IKZF1 gene with the t(1;9)(q24;q34) and illustrate the importance of comprehensive cytogenetic and molecular evaluation for accurate prediction of prognosis in patients with B-cell ALL. PMID:26600955

Closed retrograde retrieval of the distal broken segment of femoral cannulated intramedullary nail using a ball-tipped guide wire.

PubMed

Metikala, Sreenivasulu; Mohammed, Riazuddin

2011-07-01

Extracting broken segments of intramedullay nails from long bones can be an operative challenge, particularly from the distal end. We report a case series where a simple and reproducible technique of extracting broken femoral cannulated nails using a ball-tipped guide wire is described. This closed technique involves no additional equipment or instruments. Eight patients who underwent the described method were included in the study. The technique involves using a standard plain guide wire passed through the cannulated distal broken nail segment after extraction of the proximal nail fragment. The plain guide wire is then advanced distally into the knee joint carefully under fluoroscopy imaging. Over this wire, a 5-millimeter (mm) cannulated large drill bit is used to create a track up to the distal broken nail segment. Through the small knee wound, a ball-tipped guide wire is passed, smooth end first, till the ball engages the end of the nail. The guide wire is then extracted along with the broken nail through the proximal wound. The method was successfully used in all eight patients for removal of broken cannulated intramedullary nail from the femoral canal without any complications. All patients underwent exchange nailing with successful bone union in six months. None of the patients had any problems at the knee joint at the final follow-up. We report a technique for successful extraction of the distal fragment of broken femoral intramedullary nails without additional surgical approaches.

Machine tool locator

DOEpatents

Hanlon, John A.; Gill, Timothy J.

2001-01-01

Machine tools can be accurately measured and positioned on manufacturing machines within very small tolerances by use of an autocollimator on a 3-axis mount on a manufacturing machine and positioned so as to focus on a reference tooling ball or a machine tool, a digital camera connected to the viewing end of the autocollimator, and a marker and measure generator for receiving digital images from the camera, then displaying or measuring distances between the projection reticle and the reference reticle on the monitoring screen, and relating the distances to the actual position of the autocollimator relative to the reference tooling ball. The images and measurements are used to set the position of the machine tool and to measure the size and shape of the machine tool tip, and examine cutting edge wear. patent

Remote detection of insect epidemics in conifers

NASA Technical Reports Server (NTRS)

Heller, R. C.

1970-01-01

With properly exposed color or infrared color film, discolored foliage caused by insect infestations in ponderosa pine is detectable on moderately small-scale photographs with acceptable accuracies. Black and white photographs which matched the wavebands of the ERTS multispectral scanner were combined into one additive color photo. This imagery was not as useful as photographs taken on color, color infrared, or color film with a minus blue filter. Based on the high-altitude color and color infrared photos obtained, it is concluded that only insect infestations larger than 100 meters in diameter are detectable on ERTS imagery.

Free vibration analysis of linear particle chain impact damper

NASA Astrophysics Data System (ADS)

Gharib, Mohamed; Ghani, Saud

2013-11-01

Impact dampers have gained much research interest over the past decades that resulted in several analytical and experimental studies being conducted in that area. The main emphasis of such research was on developing and enhancing these popular passive control devices with an objective of decreasing the three parameters of contact forces, accelerations, and noise levels. To that end, the authors of this paper have developed a novel impact damper, called the Linear Particle Chain (LPC) impact damper, which mainly consists of a linear chain of spherical balls of varying sizes. The LPC impact damper was designed utilizing the kinetic energy of the primary system through placing, in the chain arrangement, a small-sized ball between each two large-sized balls. The concept of the LPC impact damper revolves around causing the small-sized ball to collide multiple times with the larger ones upon exciting the primary system. This action is believed to lead to the dissipation of part of the kinetic energy at each collision with the large balls. This paper focuses on the outcome of studying the free vibration of a single degree freedom system that is equipped with the LPC impact damper. The proposed LPC impact damper is validated by means of comparing the responses of a single unit conventional impact damper with those resulting from the LPC impact damper. The results indicated that the latter is considerably more efficient than the former impact damper. In order to further investigate the LPC impact damper effective number of balls and efficient geometry when used in a specific available space in the primary system, a parametric study was conducted and its result is also explained herein. Single unit impact damper [14-16]. Multiunit impact damper [17,18]. Bean bag impact damper [19,20]. Particle/granular impact damper [21,23,22]. Resilient impact damper [24]. Buffered impact damper [25-27]. Multiunit impact damper consists of multiple masses instead of a single mass. This produces a smaller contact force for each mass while maintaining the same effect of the single unit impact damper. The analytical and experimental work showed that the multiunit impact damper is more functional than the conventional single unit impact damper in reducing noise and vibration [17]. The bean bag impact damper is considered as another form of multiunit impact damper. It consists of a flexible bag packed with small spherical particles (e.g. lead shots). The resilience of the damper can be varied by adjusting the tightness of the flexible bag. It is found that the bean bag impact damper is better than the conventional impact damper in vibration suppression, contact forces reductions, and noise attenuation [19]. The particle/granular impact damper consists of a cavity(s) filled with ceramic/metal particles or powders with small granule sizes. Better damping performances are achieved when using metal particles with high density (lead or tungsten steel) [23]. Other investigations recommended using multiple particle impact dampers that involve friction, impact and shear mechanisms to achieve optimal damping effect [22]. The resilient impact damper is similar to the conventional impact dampers. The only difference is that the deformation of the impact damper with the stops during the collision is taken into account [24]. The buffered impact damper is an extension of the resilient impact damper by adding a flexible buffer layer to the stops to absorb the energy of the moving mass. The experimental work shows that the buffer zone reduces the impact forces, avoids high acceleration and reduces the contact forces by absorbing more of the impact energy and increasing the contact time [25].

Bending stresses in spherically hollow ball bearing and fatigue experiments

NASA Technical Reports Server (NTRS)

Nypan, L. J.; Coe, H. H.; Parker, R. J.

1975-01-01

Spherically hollow balls of 21.7, 50.0, and 56.5 percent mass reduction were operated in ball bearings and in a five-ball fatigue tester with differing outcomes. Available theoretical and experimental treatments of stresses in spherically hollow balls are reviewed and compared. Bending stresses are estimated for these spherically hollow balls to better understand the differences in ball bearing and fatigue test experience.

IRAS colors within M31: Evidence for deficiency of very small grains?

NASA Technical Reports Server (NTRS)

Xu, Cong; Helou, George

1994-01-01

Significant differences are found in the IRAS color-color diagrams of small regions (2 min x 2 min, or 0.4 x 1.8 kpc) within the disk of M31 compared to Galactic cirrus, most noticeably demonstrated by a trend of low 60 to 100 micrometer surface brightness ratio and high 12 to 25 micrometer ratio. Based on physical arguments, we conclude that these color differences are best explained by assuming that 'very small grains' (VSG; but not polycylic aromatic hydrocarbons) are only half as abundant in M31 as they are in Galactic cirrus. We confirm this conclusion and test its detailed agreement with data by using the phenomenological model of Desert et al. (1990). In particular, we show that the data cannot be explained by postulating weaker UV heating in the disk of M31. We also show that the VSG-deficient model predicts correctly the correspondence between the IRAS colors and the 100 micrometer emissivity per H I atom in the outer disk of M31. 'Very small grains' are a leading candidate for the carrier of the 2175 A bump in the extinction curve. Our suggested VSG deficiency in M31 is thus consistent with recent Hubble Space Telescope (HST) observations which show evidence for a weaker and narrower 2175 A bump on the M31 extinction curve. Some speculation is offered as to possible links between very small grains and the low rate of current star formation in M31.

Color naming: color scientists do it between Munsell sheets of color

NASA Astrophysics Data System (ADS)

Beretta, Giordano B.; Moroney, Nathan M.

2010-01-01

With the advent of high dynamic range imaging and wide gamut color spaces, gamut mapping algorithms have to nudge image colors much more drastically to constrain them within a rendering device's gamut. Classical colorimetry is concerned with color matching and the developed color difference metrics are for small distances. For larger distances, categorization becomes a more useful concept. In the gamut mapping case, lexical distance induced by color names is a more useful metric, which translates to the condition that a nudged color may not cross a name boundary. The new problem is to find these color name boundaries. We compare the experimental procedures used for color naming by linguists, ethnologists, and color scientists and propose a methodology that leads to robust repeatable experiments.

Bending stresses in spherically hollow ball bearing and fatigue experiments

NASA Technical Reports Server (NTRS)

Nypan, L. J.; Coe, H. H.; Parker, R. J.

1975-01-01

Spherically hollow balls of 21.7, 50.0 and 56.5 per cent mass reduction have been operated in ball bearings and in a 5-ball fatigue tester with differing outcomes. Available theoretical and experimental treatments of stresses in spherically hollow balls are reviewed and compared. Bending stresses are estimated for these spherically hollow balls to better understand the differences in ball bearing and fatigue test experience.

A formula for comparison of selected sport ball compressibility.

PubMed Central

Dowell, L J; Krebs, G

1991-01-01

The purpose of this study was to develop a formula to determine and compare the compressibility of selected sport balls. Six balls (basketball, volleyball, soccer ball, baseball, handball, golf ball) were dropped ten times from each of four different heights onto a smooth solid surface overlaid with a white sheet of typing paper, overlaid with a sheet of carbon paper. The diameter of the area of contact of each ball imprinted onto the typing paper was measured in millimetres with calipers. From the data, the distance (d) that each ball compressed for each velocity (v) was calculated. It was found that a linear relationship existed between velocity at impact and the distance for each ball studied. The compressibility coefficient (c) for each ball was calculated and a formula was developed to determine the distance each ball would compress at a given velocity. When velocity is measured in metres per second and the distance a ball compresses is measured in millimetres, the formula to determine d for selected balls, in order of compressibility is: basketball d = 3.07v, volleyball d = 2.90v, soccer ball d = 2.80v, baseball d = 0.77v, handball d = 0.53v, and golf ball d = 0.17v. PMID:1913029

A geometric constraint, the head-to-tail exclusion rule, may be the basis for the isolated-pentagon rule in fullerenes with more than 60 vertices

PubMed Central

Schein, Stan; Friedrich, Tara

2008-01-01

Carbon atoms self-assemble into the famous soccer-ball shaped Buckminsterfullerene (C60), the smallest fullerene cage that obeys the isolated-pentagon rule (IPR). Carbon atoms self-assemble into larger (n > 60 vertices) empty cages as well—but only the few that obey the IPR—and at least 1 small fullerene (n ≤ 60) with adjacent pentagons. Clathrin protein also self-assembles into small fullerene cages with adjacent pentagons, but just a few of those. We asked why carbon atoms and clathrin proteins self-assembled into just those IPR and small cage isomers. In answer, we described a geometric constraint—the head-to-tail exclusion rule—that permits self-assembly of just the following fullerene cages: among the 5,769 possible small cages (n ≤ 60 vertices) with adjacent pentagons, only 15; the soccer ball (n = 60); and among the 216,739 large cages with 60 < n ≤ 84 vertices, only the 50 IPR ones. The last finding was a complete surprise. Here, by showing that the largest permitted fullerene with adjacent pentagons is one with 60 vertices and a ring of interleaved hexagons and pentagon pairs, we prove that for all n > 60, the head-to-tail exclusion rule permits only (and all) fullerene cages and nanotubes that obey the IPR. We therefore suggest that self-assembly that obeys the IPR may be explained by the head-to-tail exclusion rule, a geometric constraint. PMID:19050075

Enhancement of Perfluoropolyether Boundary Lubrication Performance

NASA Technical Reports Server (NTRS)

Jones, W. R., Jr.; Ajayi, O. O.; Wedeven, L. D.

1996-01-01

A ball bearing simulator operating under starved conditions was used to perform screening tests to evaluate the boundary lubrication performance of a branched perfluoropolyether (PFPE), K-143 AB. Several approaches to enhance boundary lubrication were studied. These included: (1) soluble boundary additives, (2) bearing surface modifications, (3) 'run-in' surface films, and (4) ceramic bearing components. In addition, results were compared with two non-perfluorinated liquid lubricant formulations. Based on these tests, the following tentative conclusions can be made: (1) Substantial improvements in boundary lubrication performance were observed with a beta-diketone boundary additive and a tricresyl phosphate (TCP) liquid surface pretreatment, (2) the use of rough Si3N4 balls (R(sub a) = 40 micro-inch) also provided increases in test duration, but with concomitant abrasive wear, (3) moderate improvements were seen with two boundary additives (a phosphine and a phosphatriazine) and a neat (100%) fluid (a carboxylic acid terminated PFPE); and small improvements with surface pretreatments with synthetic hydrocarbons, a polytetrafluoroethylene (PTFE) coating, and TiC coated 440 C and smooth Si3N4 balls (R(sub a) = 1 micro-inch), and (4) two non-PFPE lubricant formulations (a polyalphaolefin (PAO) and synthetic hydrocarbon) yielded substantial improvements.

Measurement of the temporal progression of scour in a pool-riffle sequence in a gravel bed stream using an electronic scour monitor

NASA Astrophysics Data System (ADS)

Devries, Paul; Burges, Stephen J.; Daigneau, Julie; Stearns, Daniel

2001-11-01

A relatively inexpensive prototype monitor was designed and developed to record temporal variation in scour depth and was field-tested in a gravel bed stream. The device consists of plastic practice golf balls that are fitted internally with ring magnets and strung on a two-conductor cable enclosing a small reed switch. The balls are installed and oriented near-vertically in the streambed. As each ball is disturbed and released, it slides along the cable past the reed switch, and the time of circuit closure caused by passage of the magnet is recorded by a data logger. The device can be applied in arrays that span large areas of the streambed, including in wide channels that are inaccessible during a flood. Data obtained from 19 devices installed in an aggrading site described scouring processes in a pool-riffle interface during a bed load transport event. Substantial bed excavation occurred in the region of the pool edge during the rising stage, indicating existence of a local, temporally varying imbalance in bed load transport rate. Bed disturbance in the rest of the site prior to aggradation was limited to the surface and immediate subpavement layer.

Rep. Bill Nelson inside a personal rescue sphere

NASA Image and Video Library

1985-09-25

U.S. Representative Bill Nelson (D.,Florida) gives a thumbs up signal from inside a small ball called a personal rescue sphere (PRS). The PRS is not part of STS 61-C hardware, but serves to evaluate a subject's reaction to close quarters. The photo was taken through a visor on the 39-inch diameter fabric rescue sphere.

Micropolitics, Leadership and All That...The Need To Increase the Micropolitical Awareness and Skills of School Leaders.

ERIC Educational Resources Information Center

West, Mel

1999-01-01

Explores the influence of micropolitical factors on school organization and management, drawing on Ball's idea regarding the inevitability of micropolitics in school settings. Using Edgar Schein's small-group perspective, shows how micropolitical analyses of school cultures and teacher behavior can be used to increase school leaders'…

Play Ball? Reflections on My Father's Youth Baseball Experiences and Why They Matter

ERIC Educational Resources Information Center

Kimiecik, Jay C.

2016-01-01

The author uses his father's autobiographical writings about the small-town, baseball experiences of his youth as background for discussing the significant cultural shifts that have dramatically changed the nature of the game from a free-play experience for neighborhood kids to an organized youth-league sport. In contrast to his father's day, the…

An Evaluation of the Efficacy of a Laboratory Exercise on Cellular Respiration

ERIC Educational Resources Information Center

Scholer, Anne-Marie; Hatton, Mary

2008-01-01

This study is an analysis of the effectiveness of a faculty-designed laboratory experience about a difficult topic, cellular respiration. The activity involves a hands-on model of the cellular-respiration process, making use of wooden ball-and-stick chemistry models and small toy trucks on a table top model of the mitochondrion. Students…

A Force-Velocity Relationship and Coordination Patterns in Overarm Throwing

PubMed Central

van den Tillaar, Roland; Ettema, Gertjan

2004-01-01

A force-velocity relationship in overarm throwing was determined using ball weights varying from 0.2 to 0.8 kg. Seven experienced handball players were filmed at 240 frames per second. Velocity of joints of the upper extremity and ball together with the force on the ball were derived from the data. A statistically significant negative relationship between force and maximal ball velocity, as well as between ball weight and maximal ball velocity was observed. Also, with increase of ball weight the total throwing movement time increased. No significant change in relative timing of the different joints was demonstrated, suggesting that the subjects did not change their “global ”coordination pattern (kinematics) within the tested range of ball weights. A simple model revealed that 67% of ball velocity at ball release was explained by the summation of effects from the velocity of elbow extension and internal rotation of the shoulder. With regard to the upper extremity the internal rotation of the shoulder and elbow extension are two important contributors to the total ball velocity at release. Key Points An inverse relationship between load and velocity and a linear force-velocity exists in overarm throwing with ball weights varying from 0.2 to 0.8 kg. Qualitatively, no changes in coordination pattern (relative timing) occur with increasing ball weight within the tested range of ball weights. The absolute throwing movement time increased with ball weight. Quantitatively, with regard to the upper extremity, the internal rotation of the shoulder and elbow extension are two important contributors to the total ball velocity at release. PMID:24624005

Experimental evaluation of 150-millimeter bore ball bearing to 3 million DN using either solid or drilled balls

NASA Technical Reports Server (NTRS)

Scibbe, H. W.; Munson, H. E.

1973-01-01

Seven 150-mm bore ball bearings were run under 8900 Newton (2000 lb) thrust load at speeds from 6670 to 20,000 rpm (1 to 3 million DN). Four of the bearings had conventional solid balls and three bearing had drilled (cylindrically hollow) balls with 50 percent mass reduction. The bearings were under-race cooled and slot-lubricated with Type 2 ester oil at flow rates from 4.35 to 5.80 liters per minute (1.15 to 1.57 gal min). Friction torque and temperatures were measured on all bearings. No significant difference in torque was noted, between the solid and drilled ball bearings. One bearing of each type was rerun at 17,800 Newtons (4000 lb) thrust load. The solid ball bearings performed satisfactorily at 3 million DN. However, at about 2 million DN the drilled ball bearing experienced a broken ball and cracks appeared in two other balls as the result of flexure fatigue. Metallurgical examination of the cracked balls indicated a brittle structure in the bore of the drilled balls.

21 CFR 73.1647 - Copper powder.

Code of Federal Regulations, 2010 CFR

2010-04-01

... good manufacturing practice. (d) Labeling. The color additive and any mixture prepared therefrom... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive... contains small amounts of stearic or oleic acid as lubricants. (2) Color additive mixtures for drug use...

21 CFR 73.1647 - Copper powder.

Code of Federal Regulations, 2014 CFR

2014-04-01

... good manufacturing practice. (d) Labeling. The color additive and any mixture prepared therefrom... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive... contains small amounts of stearic or oleic acid as lubricants. (2) Color additive mixtures for drug use...

21 CFR 73.1647 - Copper powder.

Code of Federal Regulations, 2012 CFR

2012-04-01

... good manufacturing practice. (d) Labeling. The color additive and any mixture prepared therefrom... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive... contains small amounts of stearic or oleic acid as lubricants. (2) Color additive mixtures for drug use...

21 CFR 73.1647 - Copper powder.

Code of Federal Regulations, 2013 CFR

2013-04-01

... good manufacturing practice. (d) Labeling. The color additive and any mixture prepared therefrom... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive... contains small amounts of stearic or oleic acid as lubricants. (2) Color additive mixtures for drug use...

Flight trajectory of a rotating golf ball with grooves

NASA Astrophysics Data System (ADS)

Baek, Moonheum; Kim, Jooha; Choi, Haecheon

2014-11-01

Dimples are known to reduce drag on a sphere by the amount of 50% as compared to a smooth surface. Despite the advantage of reducing drag, dimples deteriorate the putting accuracy owing to their sharp edges. To minimize this putting error but maintain the same flight distance, we have devised a grooved golf ball (called G ball hereafter) for several years. In this study, we modify the shape and pattern of grooves, and investigate the flow characteristics of the G ball by performing wind-tunnel experiments at the Reynolds numbers of 0 . 5 ×105 - 2 . 5 ×105 and the spin ratios (ratio of surface velocity to the free-stream velocity) of 0 - 0.6 that include the real golf-ball velocity and rotational speed. We measure the drag and lift forces on the rotating G ball and compare them with those of a smooth ball and two well-known dimpled balls. The lift-to-drag ratio of the G ball is much higher than that of a smooth ball and is in between those of the two dimpled balls. The trajectories of flying golf balls are computed. The flight distance of G ball is almost the same as that of one dimpled ball but slightly shorter than that of the other dimpled ball. The fluid-dynamic aspects of these differences will be discussed at the talk. Supported by 2011-0028032, 2014M3C1B1033980.

Effects of ball-milling on lithium insertion into multi-walled carbon nanotubes synthesized by thermal chemical vapour deposition

NASA Astrophysics Data System (ADS)

Eom, JiYong; Kim, DongYung; Kwon, HyukSang

The effects of ball-milling on Li insertion into multi-walled carbon nanotubes (MWNTs) are presented. The MWNTs are synthesized on supported catalysts by thermal chemical vapour deposition, purified, and mechanically ball-milled by the high energy ball-milling. The purified MWNTs and the ball-milled MWNTs were electrochemically inserted with Li. Structural and chemical modifications in the ball-milled MWNTs change the insertion-extraction properties of Li ions into/from the ball-milled MWNTs. The reversible capacity (C rev) increases with increasing ball-milling time, namely, from 351 mAh g -1 (Li 0.9C 6) for the purified MWNTs to 641 mAh g -1 (Li 1.7C 6) for the ball-milled MWNTs. The undesirable irreversible capacity (C irr) decreases continuously with increase in the ball-milling time, namely, from 1012 mAh g -1 (Li 2.7C 6) for the purified MWNTs to 518 mAh g -1 (Li 1.4C 6) for the ball-milled MWNTs. The decrease in C irr of the ball-milled samples results in an increase in the coulombic efficiency from 25% for the purified samples to 50% for the ball-milled samples. In addition, the ball-milled samples maintain a more stable capacity than the purified samples during charge-discharge cycling.

76 FR 10335 - Ball Bearings and Parts Thereof From Germany: Initiation of Antidumping Duty Changed...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-24

... classified under the following categories: Antifriction balls, ball bearings with integral shafts, ball..., outer race, cage, rollers, balls, seals, shields, etc.) outlined above with certain limitations. With...

THE EFFECTS OF HIGH VOLTAGE CATHODE RAY IONIZING RADIATION ON SOME OF THE PHYSICAL AND CHEMICAL PROPERTIES OF WHEAT FLOUR PROTEIN

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

Alsup, E.B.

1959-01-01

The effect of irradiation on some of the physical and chemical properties of wheat flour protein was determined. A study of the baking quality and palatability of an irradiated flour product, yields of crude gluten from irradiated flour, and electrophoretic analyses of some of the protein fractions of irradiated flour were studied. Triangle taste tests indicated that 50000 rep was the dosage level at which the irradiation treatment of flour could be detected in baking powder biscuits. Taste panel scores for color, odor, and baking characteristics of biscuits made with flour treated with 100000 rep or less of ionizing radiation,more » however, were not significantly different from the scores for the control biscuits. An off-odor and darkening in color of the biscuits were readily apparent at a dosage of 500000 rep. The weight of crude gluten extracted from flour was greater from flour exposed to dosages of 1000000 rep or less than from the control flour, but no differences were found in the volumes of the baked balls of crude gluten. This indicates a greater water retention with the irradiated flour. Very small yields of crude gluten at dosages of 3000000 rep or more indicated that definite changes had occurred in the protein structure. Electrophoretic analyses by the moving boundary method were performed on acetic acid extracts of whole flour in a citric acid-disodium phos, phate buffer pH 2.2, ionic strength 0.024. Electrophoretic patterns obtained from the non-irradiated flour indicated that there were at least six separate protein components present, including one which was fast-moving and high in relative concentration, one which was slow-moving and medium high in relative concentration, and four relatively small components. Irradiation of the flour with 300000 rep produced no apparent changes in the electrophoretic patterns obtained, but it 1000000 rep or more, the relative concentrations of the two largest components were changed (the slow-moving one becoming larger and the fastermoving one smaller with each increase in dosage). Also with increased radiation dosages, the peaks of the smaller components became less distinct until only the two main peaks were distinguishable at 10000000 rep. (Dissertition Abstr., 23: No. 4, 1962)« less

Finite element analysis of the axial stiffness of a ball screw

NASA Astrophysics Data System (ADS)

Zhou, L.-X.; Li, P.-Y.

2018-06-01

The ball screw was developed for high speed and high precision operation; therefore, increasingly greater demands have been placed on the stiffness of the ball screw. Firstly, ANSYS software was used to compare the axial stiffness of a single-nut and single-arc ball screw and a single-nut and double-arc ball screw when the spiral angle is not considered. On this basis, the model of a single-nut ball screw was established taking into consideration the spiral lead angle, and then the variations in displacement and stiffness when the ball screw pair was subjected to an axial force were determined. The axial contact stiffness of the double-nut ball screw pair, subject to a pre-tightening force, was analyzed, according to the above-mentioned steps. The simulation results demonstrated that under the same working conditions, the stiffness of the double-arc ball screw was larger by between 5∼100 N/um than that of the single-arc ball screw. The spiral lead angle increased the axial stiffness of the ball screw pair, and the axial stiffness of the double-nut ball screw pair subject to a pre-tightening force was larger by between 790∼1360 N/um than that of the axial stiffness of the single-nut ball screw pair.

Comparison of experimental and predicted performance of 150-millimeter-bore solid and drilled ball bearings to 3 million DN

NASA Technical Reports Server (NTRS)

Scibbe, H. W.; Munson, H. E.

1974-01-01

Seven 150-millimeter-bore ball bearings were run under 8900-newton (2000-lbf) thrust load at speeds from 6670 to 20,000 rpm (1 million to 3 million DN). Four of the bearings had conventional solid balls, and three bearings had drilled (cylindrically hollow) balls with 50-percent mass reduction. The bearings were under-race cooled and slot lubricated with a type 2 ester oil at flow rates from 4.35 x 0.001 to 5.94 x 0.001 cubic meter/min (1.15 to 1.57 gal/min). Friction torque and temperature were measured on all bearings. While there was considerable spread in the temperature data, the drilled ball bearings tended to run slightly cooler than the solid ball bearings at higher speeds. No significant difference in torque was noted, however, between the solid and drilled ball bearings. One bearing of each type was rerun at 17,800-newton (4000-lbf) thrust load. The solid ball bearings performed satisfactorily at 3 million DN. However, at about 2 million DN the drilled ball bearing experienced a broken ball, and cracks appeared in other balls as a result of flexure fatigue. Metallurgical examination of the cracked balls indicated a brittle structure in the bore of the drilled balls.

78 FR 76104 - Ball Bearings and Parts Thereof From Japan and the United Kingdom: Notice of Reinstatement of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-16

... following categories: Antifriction balls, ball bearings with integral shafts, ball bearings (including..., rollers, balls, seals, shields, etc.) outlined above with certain limitations. With regard to finished...

Enhancing the Bounce of a Ball

NASA Astrophysics Data System (ADS)

Cross, Rod

2010-10-01

In sports such as baseball, softball, golf, and tennis, a common objective is to hit the ball as fast or as far as possible. Another common objective is to hit the ball so that it spins as fast as possible, since the trajectory of the ball through the air is strongly affected by ball spin. In an attempt to enhance both the coefficient of restitution (COR) and the spin of a golf ball, I conducted several experiments to see what would happen when a 45-g, 42.8-mm diameter golf ball bounced on: (a) a 58-mm diameter, 103-g Super Ball®; (b) an 8-mm thick, 56-mm diameter circular disk of Super Ball material cut from a large Super Ball and glued to a 3.4-kg lead brick; and (c) a 3-mm thick sheet of rubber glued to a 3.4-kg lead brick. (See Fig. 1.)

Sonic beam model of Newton’s cradle

NASA Astrophysics Data System (ADS)

Menger, Fredric M.; Rizvi, Syed A. A.

2016-07-01

The motions of Newton’s cradle, consisting of several steel balls hanging side-by-side, have been analysed in terms of a sound pulse that travels via points of contact among the balls. This presupposes a focused energy beam. When the pulse reaches the fifth and final ball, the energy disperses and dislocates the ball with a trajectory equivalent to that of the first ball after it was released. The pulse passes unchanged through the internal balls without, therefore, causing movement of these balls. Lack of movement can be affirmed by immobilising one or more of the balls, thereby disproving both the gap and vibrating lattice models. This also contrasts with previous mechanisms that postulate complete energy dispersal within a ball prior to transferring the energy to another ball. Inserting an inelastic barrier between the second and third balls disrupts the pulse such that it spreads out to reach regions that are not in contact with another ball. As a result, the normally stationary third ball is forced into a forward motion, thereby pushing the fourth and fifth ball with it as a single unit. The model is valuable in explaining a fact that has puzzled physicists for generations: why is only one motional mode observed among a multitude of motions that maintain a constant momentum and kinetic energy as required by the laws of physics? The answer lies in the fact that all motions, except the one that is actually observed, require a rebound in one or more of the balls. Since the energy beam formed upon impact is unidirectional, reverse motions are not accommodated.

Individual ball possession in soccer

PubMed Central

Hoernig, Martin

2017-01-01

This paper describes models for detecting individual and team ball possession in soccer based on position data. The types of ball possession are classified as Individual Ball Possession (IBC), Individual Ball Action (IBA), Individual Ball Control (IBC), Team Ball Possession (TBP), Team Ball Control (TBC) und Team Playmaking (TPM) according to different starting points and endpoints and the type of ball control involved. The machine learning approach used is able to determine how long the ball spends in the sphere of influence of a player based on the distance between the players and the ball together with their direction of motion, speed and the acceleration of the ball. The degree of ball control exhibited during this phase is classified based on the spatio-temporal configuration of the player controlling the ball, the ball itself and opposing players using a Bayesian network. The evaluation and application of this approach uses data from 60 matches in the German Bundesliga season of 2013/14, including 69,667 IBA intervals. The identification rate was F = .88 for IBA and F = .83 for IBP, and the classification rate for IBC was κ = .67. Match analysis showed the following mean values per match: TBP 56:04 ± 5:12 min, TPM 50:01 ± 7:05 min and TBC 17:49 ± 8:13 min. There were 836 ± 424 IBC intervals per match and their number was significantly reduced by -5.1% from the 1st to 2nd half. The analysis of ball possession at the player level indicates shortest accumulated IBC times for the central forwards (0:49 ± 0:43 min) and the longest for goalkeepers (1:38 ± 0:58 min), central defenders (1:38 ± 1:09 min) and central midfielders (1:27 ± 1:08 min). The results could improve performance analysis in soccer, help to detect match events automatically, and allow discernment of higher value tactical structures, which is based on individual ball possession. PMID:28692649

Manipulator for rotating and examining small spheres

DOEpatents

Weinstein, B.W.; Willenborg, D.L.

1980-02-12

A manipulator is disclosed which provides fast, accurate rotational positioning of a small sphere, such as an inertial confinement fusion target, which allows inspecting of the entire surface of the sphere. The sphere is held between two flat, flexible tips which move equal amounts in opposite directions. This provides rolling of the ball about two orthogonal axes without any overall translation. The manipulator may be controlled, for example, by an x- and y-axis driven controlled by a mini-computer which can be programmed to generate any desired scan pattern. 8 figs.

Biomass Burning Research Using DOE ARM Single-Particle Soot Photometer (SP2) Field Campaign Report

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

Onasch, Timothy B; Sedlacek, Arthur J; Lewis, Ernie

The focus of this laboratory study was to investigate the chemical and optical properties, and the detection efficiencies, of tar balls generated in the laboratory using the same instruments deployed on the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility Gulfstream-1 (G-1) aircraft during the 2013 Biomass Burning Observation Project (BBOP) field study, during which tar balls were observed in wildland biomass burning particulate emissions. Key goals of this laboratory study were: (a) measuring the chemical composition of tar balls to provide insights into the atmospheric processes that form (evaporation/oxidation) and modify them in biomass burningmore » plumes, (b) identifying whether tar balls contain refractory black carbon, (c) determining the collection efficiencies of tar balls impacting on the 600oC heated tungsten vaporizer in the Aerodyne Soot Particle Aerosol Mass Spectrometer (SP-AMS) (i.e., given the observed low volatilities, AMS measurements might underestimate organic biomass burning plume loadings), and (d) measuring the wavelength-dependent, mass-specific absorption cross-sections of brown carbon components of tar balls. This project was funded primarily by the DOE Atmospheric System Research (ASR) program, and the ARM Facility made their single-particle soot photometer (SP2) available for September 1-September 31, 2016 in the Aerodyne laboratories. The ARM mentor (Dr. Sedlacek) requested no funds for mentorship or data reduction. All ARM SP2 data collected as part of this project are archived in the ARM Data Archive in accordance with established protocols. The main objectives of the ARM Biomass Burning Observation Period (BBOP, July-October, 2013) field campaign were to (1) assess the impact of wildland fires in the Pacific Northwest on climate, through near-field and regional intensive measurement campaigns, and (2) investigate agricultural burns to determine how those biomass burn plumes differ from those from wildland fires. During BBOP, tar balls, small solid particles of organic substances, were observed downwind from wildland fires (at plume ages of 0-3 hours), but not agricultural burns. Observations of the tar balls on transmission electron microscope (TEM) grids suggest that they formed during atmospheric transport, likely due to the same atmospheric processes that increased the oxidation levels of the organic aerosol. Preliminary analyses suggest that tar balls may account for almost 50% of the total particle number, and 30% of the total organic particle mass, of the aerosol emitted from the burning events. These BBOP observations are described in detail in a manuscript in preparation (Sedlacek et al., 2017). The current laboratory study lasted four weeks and was conducted in the aerosol laboratories located at Aerodyne Research, Inc. in Billerica, Massachusetts. Tar balls were generated from several different biomass fuels, including samples from BBOP-related field sites, following literature procedures (Hoffer, Tóth, Nyirö-Kósa, Pósfai, and Gelencsér, 2016; Tóth, Hoffer, Nyirö-Kósa, Pósfai, and Gelencsér, 2014), and they were characterized using the same equipment used during the 2013 BBOP study, specifically the SP-AMS, SP2 and TEM. This study determined that laboratory-generated tar balls (1) are refractory with respect to TEM analysis in a similar manner to those collected during BBOP from wildland fires, (2) are composed of organic material with some refractory carbon components, (3) can be measured quantitatively by the SP-AMS, strengthening observations during BBOP, (4) absorb visible light, and (4) are dominated by unsaturated hydrocarbons that may be responsible for their light-absorbing properties. The results from this project are already being incorporated into our analysis of the formation processes and emission rates of tar balls as a function of fuel and combustion conditions from wildland fires.« less

Optimum Projection Angle for Attaining Maximum Distance in a Soccer Punt Kick

PubMed Central

Linthorne, Nicholas P.; Patel, Dipesh S.

2011-01-01

To produce the greatest horizontal distance in a punt kick the ball must be projected at an appropriate angle. Here, we investigated the optimum projection angle that maximises the distance attained in a punt kick by a soccer goalkeeper. Two male players performed many maximum-effort kicks using projection angles of between 10° and 90°. The kicks were recorded by a video camera at 100 Hz and a 2 D biomechanical analysis was conducted to obtain measures of the projection velocity, projection angle, projection height, ball spin rate, and foot velocity at impact. The player’s optimum projection angle was calculated by substituting mathematical equations for the relationships between the projection variables into the equations for the aerodynamic flight of a soccer ball. The calculated optimum projection angles were in agreement with the player’s preferred projection angles (40° and 44°). In projectile sports even a small dependence of projection velocity on projection angle is sufficient to produce a substantial shift in the optimum projection angle away from 45°. In the punt kicks studied here, the optimum projection angle was close to 45° because the projection velocity of the ball remained almost constant across all projection angles. This result is in contrast to throwing and jumping for maximum distance, where the projection velocity the athlete is able to achieve decreases substantially with increasing projection angle and so the optimum projection angle is well below 45°. Key points The optimum projection angle that maximizes the distance of a punt kick by a soccer goalkeeper is about 45°. The optimum projection angle is close to 45° because the projection velocity of the ball is almost the same at all projection angles. This result is in contrast to throwing and jumping for maximum distance, where the optimum projection angle is well below 45° because the projection velocity the athlete is able to achieve decreases substantially with increasing projection angle. PMID:24149315

Social causes of correlational selection and the resolution of a heritable throat color polymorphism in a lizard.

PubMed

Sinervo, B; Bleay, C; Adamopoulou, C

2001-10-01

When selection acts on social or behavioral traits, the fitness of an individual depends on the phenotypes of its competitors. Here, we describe methods and statistical inference for measuring natural selection in small social groups. We measured selection on throat color alleles that arises from microgeographic variation in allele frequency at natal sites of side-blotched lizards (Uta stansburiana). Previous game-theoretic analysis indicates that two color morphs of female side-blotched lizards are engaged in an offspring quantity-quality game that promotes a density- and frequency-dependent cycle. Orange-throated females are r-strategists. They lay large clutches of small progeny, which have poor survival at high density, but good survival at low density. In contrast, yellow-throated females are K-strategists. They lay small clutches of large progeny, which have good survival at high density. We tested three predictions of the female game: (1) orange progeny should have a fitness advantage at low density; (2) correlational selection acts to couple color alleles and progeny size; and (3) this correlational selection arises from frequency-dependent selection in which large hatchling size confers an advantage, but only when yellow alleles are rare. We also confirmed the heritability of color, and therefore its genetic basis, by producing progeny from controlled matings. A parsimonious cause of the high heritability is that three alleles (o, b, y) segregate as one genetic factor. We review the physiology of color formation to explain the possible genetic architecture of the throat color trait. Heritability of color was nearly additive in our breeding study, allowing us to compute a genotypic value for each individual and thus predict the frequency of progeny alleles released on 116 plots. Rather than study the fitness of individual progeny, we studied how the fitness of their color alleles varied with allele frequency on plots. We confirmed prediction 1: When orange alleles are present in female progeny, they have higher fitness at low density when compared to other alleles. Even though the difference in egg size of the female morphs was small (0.02 g), it led to knife-edged survival effects for their progeny depending on local social context. Selection on hatchling survival was not only dependent on color alleles, but on a fitness interaction between color alleles and hatchling size, which confirmed prediction 2. Sire effects, which are not confounded by maternal phenotype, allowed us to resolve the frequency dependence of correlational selection on egg size and color alleles and thereby confirmed prediction 3. Selection favored large size when yellow sire alleles were rare, but small size when they were common. Correlational selection promotes the formation of a self-reinforcing genetic correlation between the morphs and life-history variation, which causes selection in the next density and frequency cycle to be exacerbated. We discuss general conditions for the evolution of self-reinforcing genetic correlations that arise from social selection associated with frequency-dependent sexual and natural selection.

Pulse analysis of acoustic emission signals. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Houghton, J. R.

1976-01-01

A method for the signature analysis of pulses in the frequency domain and the time domain is presented. Fourier spectrum, Fourier transfer function, shock spectrum and shock spectrum ratio are examined in the frequency domain analysis, and pulse shape deconvolution is developed for use in the time domain analysis. To demonstrate the relative sensitivity of each of the methods to small changes in the pulse shape, signatures of computer modeled systems with analytical pulses are presented. Optimization techniques are developed and used to indicate the best design parameters values for deconvolution of the pulse shape. Several experiments are presented that test the pulse signature analysis methods on different acoustic emission sources. These include acoustic emissions associated with: (1) crack propagation, (2) ball dropping on a plate, (3) spark discharge and (4) defective and good ball bearings.

[Laterality of upper extremity movements in infancy: observations at 4 and 9 months of age].

PubMed

Shiotani, Yuka; Matsuzawa, Shigeyuki; Ikeda, Hiroko; Sawada, Akiko; Okada, Masako; Kutsuki, Aya; Tomiwa, Kiyotaka

2010-07-01

This study investigated the process involved in the lateralization of movements during infancy by observing upper extremity movements in a laboratory setting. Reaching for flying rings, balls, mini toy cars, and small round cookies were observed and recorded by videotape at 4 and 9 months of age. The subjects were 202 infants who participated in Japan Children's Study, a cohort study on the development of sociability. Infants reached for objects significantly more frequently at 9 months (98%) than at 4 months (40%) (p<0.001). Though the lateral preference in reaching for balls at 4 months was ambiguous, reaching for toy cars was performed more frequently with the right hand at 9 months (50%) than with the left one (19%) (p<0.01). Lateralization of the upper extremity movements is thought to appear by 9 months.

MAPPING SPATIAL/TEMPORAL DISTRIBUTIONS OF GREEN MACROALGAE IN A PACIFIC NORTHWEST COASTAL ESTUARY VIA SMALL FORMAT COLOR INFRARED AERIAL PHOTOGRAPHY

EPA Science Inventory

A small format 35 mm hand-held camera with color infrared slide film was used to map blooms of benthic green macroalgae upon mudflats of Yaquina Bay estuary on the central Oregon coast, U.S.A. Oblique photographs were taken during a series of low tide events, when the intertidal...

Scoring mode and age-related effects on youth soccer teams' defensive performance during small-sided games.

PubMed

Almeida, Carlos Humberto; Duarte, Ricardo; Volossovitch, Anna; Ferreira, António Paulo

2016-07-01

This study aimed to examine the scoring mode (line goal, double goal or central goal) and age-related effects on the defensive performance of youth soccer players during 4v4 small-sided games (SSGs). Altogether, 16 male players from 2 age groups (U13, n = 8, mean age: 12.61 ± 0.65 years; U15, n = 8, 14.86 ± 0.47 years) were selected as participants. In six independent sessions, participants performed the three SSGs each during 10-min periods. Teams' defensive performance was analysed at every instant ball possession was regained through the variables: ball-recovery type, ball-recovery sector, configuration of play and defence state. Multinomial logistic regression analysis used in this study revealed the following significant main effects of scoring mode and age: (1) line goal (vs. central goal) increased the odds of regaining possession through tackle and in the defensive midfield sector, and decreased the odds of successful interceptions; (2) double goal (vs. central goal) decreased the odds of regaining possession through turnover won and with elongated playing shapes; (3) the probability of regaining possession through interception significantly decreased with age. Moreover, as youth players move forward in age groups, teams tend to structurally evolve from elongated playing shapes to flattened shapes and, at a behavioural level, from defending in depth to more risky flattened configurations. Overall, by manipulating the scoring mode in SSGs, coaches can promote functional and coadaptive behaviours between teams not only in terms of configurations of play, but also on the pitch locations that teams explore to regain possession.

Streaks Of Colored Water Indicate Surface Airflows

NASA Technical Reports Server (NTRS)

Wilcox, Floyd J., Jr.

1994-01-01

Response faster and contamination less than in oil-flow technique. Flowing colored water provides accurate and clean way to reveal flows of air on surfaces of models in wind tunnels. Colored water flows from small orifices in model, forming streak lines under influence of air streaming over surface of model.

An evaluation of satellite data for estimating the area of small forestland in the southern lower peninsula of Michigan. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Karteris, M. A. (Principal Investigator)

1980-01-01

A winter black and white band 5, a winter color, a fall color, and a diazo color composite of the fall scene were used to assess the use and potential of LANDSAT images for mapping and estimating acreage of small scattered forest tracts in Barry County, Michigan. Forests as small as 2.5 acres were mapped from each LANDSAT data source. The maps for each image were compared with an available forest-type map. Mapping errors detected were categorized as boundary and identification errors. The most frequently misclassified areas were agriculture lands, treed-bogs, brushlands and lowland and mixed hardwood stands. Stocking level affected interpretation more than stand size. The overall level of the interpretation performance was expressed through the estimation of classification, interpretation, and mapping accuracies. These accuracies ranged from 74 between 74% and 98%. Considering errors, accuracy, and cost, winter color imagery is the best LANDSAT alternative for mapping small forest tracts. However, since the availability of cloud-free winter images of the study area is significantly lower than images for other seasons, a diazo enhanced image of a fall scene is recommended as the best next best alternative.

Model of the material removal function and an experimental study on a magnetorheological finishing process using a small ball-end permanent-magnet polishing head.

PubMed

Chen, Mingjun; Liu, Henan; Cheng, Jian; Yu, Bo; Fang, Zhen

2017-07-01

In order to achieve the deterministic finishing of optical components with concave surfaces of a curvature radius less than 10 mm, a novel magnetorheological finishing (MRF) process using a small ball-end permanent-magnet polishing head with a diameter of 4 mm is introduced. The characteristics of material removal in the proposed MRF process are studied. The model of the material removal function for the proposed MRF process is established based on the three-dimensional hydrodynamics analysis and Preston's equation. The shear stress on the workpiece surface is calculated by means of resolving the presented mathematical model using a numerical solution method. The analysis result reveals that the material removal in the proposed MRF process shows a positive dependence on shear stress. Experimental research is conducted to investigate the effect of processing parameters on the material removal rate and improve the surface accuracy of a typical rotational symmetrical optical component. The experimental results show that the surface accuracy of the finished component of K9 glass material has been improved to 0.14 μm (PV) from the initial 0.8 μm (PV), and the finished surface roughness Ra is 0.0024 μm. It indicates that the proposed MRF process can be used to achieve the deterministic removal of surface material and perform the nanofinishing of small curvature radius concave surfaces.

SMALL COLOUR VISION VARIATIONS AND THEIR EFFECT IN VISUAL COLORIMETRY,

DTIC Science & Technology

COLOR VISION, PERFORMANCE(HUMAN), TEST EQUIPMENT, PERFORMANCE(HUMAN), CORRELATION TECHNIQUES, STATISTICAL PROCESSES, COLORS, ANALYSIS OF VARIANCE, AGING(MATERIALS), COLORIMETRY , BRIGHTNESS, ANOMALIES, PLASTICS, UNITED KINGDOM.

Automatic ball bar for a coordinate measuring machine

DOEpatents

Jostlein, H.

1997-07-15

An automatic ball bar for a coordinate measuring machine determines the accuracy of a coordinate measuring machine having at least one servo drive. The apparatus comprises a first and second gauge ball connected by a telescoping rigid member. The rigid member includes a switch such that inward radial movement of the second gauge ball relative to the first gauge ball causes activation of the switch. The first gauge ball is secured in a first magnetic socket assembly in order to maintain the first gauge ball at a fixed location with respect to the coordinate measuring machine. A second magnetic socket assembly secures the second gauge ball to the arm or probe holder of the coordinate measuring machine. The second gauge ball is then directed by the coordinate measuring machine to move radially inward from a point just beyond the length of the ball bar until the switch is activated. Upon switch activation, the position of the coordinate measuring machine is determined and compared to known ball bar length such that the accuracy of the coordinate measuring machine can be determined. 5 figs.

Automatic ball bar for a coordinate measuring machine

DOEpatents

Jostlein, Hans

1997-01-01

An automatic ball bar for a coordinate measuring machine determines the accuracy of a coordinate measuring machine having at least one servo drive. The apparatus comprises a first and second gauge ball connected by a telescoping rigid member. The rigid member includes a switch such that inward radial movement of the second gauge ball relative to the first gauge ball causes activation of the switch. The first gauge ball is secured in a first magnetic socket assembly in order to maintain the first gauge ball at a fixed location with respect to the coordinate measuring machine. A second magnetic socket assembly secures the second gauge ball to the arm or probe holder of the coordinate measuring machine. The second gauge ball is then directed by the coordinate measuring machine to move radially inward from a point just beyond the length of the ball bar until the switch is activated. Upon switch activation, the position of the coordinate measuring machine is determined and compared to known ball bar length such that the accuracy of the coordinate measuring machine can be determined.

Study of morphology and magnetic properties of the HoNi{sub 3} crystalline and ball-milled compound

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

Bajorek, Anna, E-mail: anna.bajorek@us.edu.pl; Silesian Center for Education and Interdisciplinary Research, University of Silesia, 75 Pułku Piechoty 1A, 41-500 Chorzów; Skornia, Paweł

2015-03-15

The morphology and magnetic properties of the HoNi{sub 3} crystalline and ball-milled intermetallic compounds are presented. The polycrystalline HoNi{sub 3} bulk compound crystallizes in the rhombohedral PuNi{sub 3} — type of crystal structure and indicates ferrimagnetic arrangement with the Curie temperature of T{sub C} = 57 ± 2 K, the helimagnetic temperature T{sub h} = 23 ± 2 K with the total saturation magnetic moment of 6.84 μ{sub B}/f.u. at 2 K. The use of the ball-milling method leads to the formation of HoNi{sub 3} nanoflakes with typical thickness of less than 100 nm prone to agglomeration upon milling. Themore » increase of grinding duration leads to the reduction in crystallite size, which was confirmed by various complementary microscopical and diffraction studies. Moreover, the increase in milling duration results in the emergence of the relatively small coercivity (H{sub C}), remanence (M{sub r}) and a variation of the saturation magnetization (M{sub S}). - Graphical abstract: Display Omitted - Highlights: • The ball-milling method exhibits significant potential for producing RT{sub 3} nanopowders. • The AFM method was used for the first time in analysis of R–T nanoflakes morphology. • HoNi{sub 3} compound forms polycrystalline and textured nanoflakes evolving upon milling. • The decrease in crystallite size via grinding is confirmed by XRD, TEM and AFM. • The magnetic parameters were sensitive to the extension of pulverization b.« less

Contamination risk of stable isotope samples during milling.

PubMed

Isaac-Renton, M; Schneider, L; Treydte, K

2016-07-15

Isotope analysis of wood is an important tool in dendrochronology and ecophysiology. Prior to mass spectrometry analysis, wood must be homogenized, and a convenient method involves a ball mill capable of milling samples directly in sample tubes. However, sample-tube plastic can contaminate wood during milling, which could lead to biological misinterpretations. We tested possible contamination of whole wood and cellulose samples during ball-mill homogenization for carbon and oxygen isotope measurements. We used a multi-factorial design with two/three steel milling balls, two sample amounts (10 mg, 40 mg), and two milling times (5 min, 10 min). We further analyzed abrasion by milling empty tubes, and measured the isotope ratios of pure contaminants. A strong risk exists for carbon isotope bias through plastic contamination: the δ(13) C value of polypropylene deviated from the control by -6.77‰. Small fibers from PTFE filter bags used during cellulose extraction also present a risk as the δ(13) C value of this plastic deviated by -5.02‰. Low sample amounts (10 mg) showed highest contamination due to increased abrasion during milling (-1.34‰), which is further concentrated by cellulose extraction (-3.38‰). Oxygen isotope measurements were unaffected. A ball mill can be used to homogenize samples within test tubes prior to oxygen isotope analysis, but not prior to carbon or radiocarbon isotope analysis. There is still a need for a fast, simple and contamination-free sample preparation procedure. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Ball valve extractor

DOEpatents

Herndon, Charles; Brown, Roger A.

2002-01-01

An apparatus and process for removing a ball valve is provided. The ball valve removal tool provides a handle sliding along the length of a shaft. One end of the shaft is secured within an interior cavity of a ball valve while the opposite end of the shaft defines a stop member. By providing a manual sliding force to the handle, the handle impacts the stop member and transmits the force to the ball valve. The direction of the force is along the shaft of the removal tool and disengages the ball valve from the ball valve housing.

Color vision but not visual attention is altered in migraine.

PubMed

Shepherd, Alex J

2006-04-01

To examine visual search performance in migraine and headache-free control groups and to determine whether reports of selective color vision deficits in migraine occur preattentively. Visual search is a classic technique to measure certain components of visual attention. The technique can be manipulated to measure both preattentive (automatic) and attentive processes. Here, visual search for colored targets was employed to extend earlier reports that the detection or discrimination of colors selective for the short-wavelength sensitive cone photoreceptors in the retina (S or "blue" cones) is impaired in migraine. Visual search performance for small and large color differences was measured in 34 migraine and 34 control participants. Small and large color differences were included to assess attentive and preattentive processing, respectively. In separate conditions, colored stimuli were chosen that would be detected selectively by either the S-, or by the long- (L or "red") and middle (M or "green")-wavelength sensitive cone photoreceptors. The results showed no preattentive differences between the migraine and control groups. For active, or attentive, search, differences between the migraine and control groups occurred for colors detected by the S-cones only, there were no differences for colors detected by the L- and M-cones. The migraine group responded significantly more slowly than the control group for the S-cone colors. The pattern of results indicates that there are no overall differences in search performance between migraine and control groups. The differences found for the S-cone colors are attributed to impaired discrimination of these colors in migraine and not to differences in attention.

Slow-Release Fertilizer

NASA Technical Reports Server (NTRS)

1998-01-01

Under an SBIR (Small Business Innovative Research), ZeoponiX, Inc., introduced ZeoPro. This product is used as a fertilizer/soil amendment for golf courses, ball fields, greenhouse and horticultural uses. A combination of superior growth medium and soil conditioner allow for nutrient supplementation and high efficiency delivery of nutrients throughout the plant. ZeoPro provides a balanced nutrient system for major, minor, and trace nutrients.

Microgravity

NASA Image and Video Library

2004-04-15

Structure Of Flame Balls At Low Lewis-numbers (SOFBALL) Experiment Mounting Structure (EMS) was used to conduct the SOFBALL experiment on Combustion Module-1. The EMS was inserted into the CM-1 combustion chamber. The chamber was filled with a lean fuel/oxidizer mixture and a spark igniter on the EMS ignited the gas. Very small, weak flames, in the shape of spheres, were formed and studied.

PANSAT satellite deployment from STS-95 Discovery's payload bay

NASA Image and Video Library

1998-10-30

STS095-E-5040 (30 Oct. 1998) --- PANSAT, a nonrecoverable satellite developed by the Naval Postgraduate School (NPS) in Monterey, California, is deployed from the cargo bay of the Earth-orbiting Space Shuttle Discovery. The small ball-shaped payload is basically a tiny telecommunications satellite. The photo was recorded with an electronic still camera (ESC) at 1:49:13 GMT, Oct. 30.

NASA DOD Lead Free Electronics Project

NASA Technical Reports Server (NTRS)

Kessel, Kurt R.

2008-01-01

The primary'technical objective of this project is to undertake comprehensive testing to generate information on failure modes/criteria to better understand the reliability of: Packages (e.g., Thin Small Outline Package [TSOP], Ball Grid Array [BGA], Plastic Dual In-line Package [PDIPD assembled and reworked with lead-free alloys Packages (e.g., TSOP, BGA, PDIP) assembled and reworked with mixed (lead/lead-free) alloys.

Inverse estimation of Vcmax, leaf area index, and the Ball-Berry parameter from carbon and energy fluxes

Treesearch

Adam Wolf; Kanat Akshalov; Nicanor Saliendra; Douglas A. Johnson; Emilio A. Laca

2006-01-01

Canopy fluxes of CO2 and energy can be modeled with high fidelity using a small number of environmental variables and ecosystem parameters. Although these ecosystem parameters are critically important for modeling canopy fluxes, they typically are not measured with the same intensity as ecosystem fluxes. We developed an algorithm to estimate leaf...

Experimental testing of centrifugal pump: small and medium sized enterprise product

NASA Astrophysics Data System (ADS)

Ismail, R.; Paddiyatu, F.; Khafidh, M.; Nugroho, S.; Sugiyanto, S.; Jamari, J.

2014-06-01

This paper reports the experimental testing for centrifugal pump for fisherman ship, manufactured by small and medium sized enterprises in Central Java Province, Indonesia. The research covers material analysis, component observation, endurance and vibration test. Six centrifugal pumps are tested and three main pump components are discussed: shaft, bearings and seals. The results show that the material of the shaft is predicted to support and transmit the load from the engine to impeller. The problem found in the tolerance and geometry accuracy of the shaft which causes difficulties during assembling process, excessive wear and leakage during testing. From the endurance and vibration test, the ball bearings fail and lock the shaft due to the fatigue on the rolling elements and raceways. The oil seal and water seal also fail in maintaining the oil and water in the chamber and induce the unlubricated system for the ball bearings. Some suggestions are delivered to improve the product quality of the centrifugal pump. A good quality of the centrifugal pump for fishermen ship and long life span is expected to be produced by local SMEs to win the free trade competition in the Indonesian market.

RCS Diversity of Electromagnetic Wave Carrying Orbital Angular Momentum.

PubMed

Zhang, Chao; Chen, Dong; Jiang, Xuefeng

2017-11-13

An electromagnetic (EM) wave with orbital angular momentum (OAM) has a helical wave front, which is different from that of the plane wave. The phase gradient can be found perpendicular to the direction of propagation and proportional to the number of OAM modes. Herein, we study the backscattering property of the EM wave with different OAM modes, i.e., the radar cross section (RCS) of the target is measured and evaluated with different OAM waves. As indicated by the experimental results, different OAM waves have the same RCS fluctuation for the simple target, e.g., a small metal ball as the target. However, for complicated targets, e.g., two transverse-deployed small metal balls, different RCSs can be identified from the same incident angle. This valuable fact helps to obtain RCS diversity, e.g., equal gain or selective combining of different OAM wave scattering. The majority of the targets are complicated targets or expanded targets; the RCS diversity can be utilized to detect a weak target traditionally measured by the plane wave, which is very helpful for anti-stealth radar to detect the traditional stealth target by increasing the RCS with OAM waves.

Two new species of Pterostichus Bonelli subgenus Pseudoferonina Ball (Coleoptera, Carabidae, Pterostichini) from the mountains of central Idaho, U.S.A.

PubMed

Bergdahl, James C; Kavanaugh, David H

2011-01-01

Two new species of Pterostichus Bonelli subgenus Pseudoferonina Ball, are described from the mountains of central Idaho: Pterostichus bousqueti Bergdahl [type locality = small tributaries of South Fork of Payette River watershed, ca. 1170 m (3840 ft), 44.0675°; -115.6822°, near Lowman, Salmon River Mountains, Boise County, Idaho, U.S.A.] and Pterostichus lolo Bergdahl [type locality = Cottonwood/Orogrande Creek, ca. 870 m (2850 ft), 46.5528°; -115.5522°, North Fork of Clearwater River watershed, Clearwater Mountains, near Bungalow, Clearwater County, Idaho, U.S.A.]. Males of Pterostichus bousqueti and Pterostichus lolo are easily distinguished from each other and the seven previously described Pseudoferonina species by the form of the median lobe of the aedeagus, and from most individuals of the other species of Pseudoferonina in Idaho by features of pronotal shape and macrosculpture. Both species appear to be obligate ripicolous hygrophiles, restricted in distribution primarily to the margins of small montane streams in forested areas. Widespread intensive stream surveys for Pseudoferonina over many years indicate the geographic ranges of both species are highly localized, and additional undescribed species may occur in Idaho.

Bilateral periorbital necrotizing fasciitis following exposure to Holi colors: a case report.

PubMed

Chauhan, Deepender; Arora, Ritu; Das, Sima; Shroff, Daraius; Narula, Ritesh

2007-01-01

Holi festival is celebrated in India traditionally by applying colors on one another. Various ocular adverse effects of these colors have been reported including conjunctivitis and corneal abrasion. We report a case of bilateral periorbital necrotizing fasciitis, following exposure to Holi colors. General physicians might encounter more such cases after exposure to Holi colors. In India, these colors are prepared on a small scale and lack any quality checks. Use of such toxic colors should be discouraged, and all doctors should caution people against using synthetic dyes. This case report highlights the need to put manufacturing of Holi colors under guidelines of the Food and Drug Cosmetic Act and the Bureau of Indian Standards.

Reconstructing color images of astronomical objects using black and white spectroscopic emulsions

NASA Technical Reports Server (NTRS)

Dufour, R. I.; Martins, D. H.

1976-01-01

A color photograph of the peculiar elliptical galaxy NGC 5128 (Centaurus A) has been reconstructed from three Kodak 103a emulsion type photographs by projecting positives of the three B&W plates through appropriate filters onto a conventional color film. The resulting photograph shows color balance and latitude characteristics superior to color photographs of similar astronomical objects made with commercially available conventional color film. Similar results have been obtained for color reconstructed photographs of the Large and Small Magellanic Clouds. These and other results suggest that these projection-reconstruction techniques can be used to obtain high-quality color photographs of astronomical objects which overcome many of the problems associated with the use of conventional color film for the long exposures required in astronomy.

Real time elastography - a non-invasive diagnostic method of small hepatocellular carcinoma in cirrhosis.

PubMed

Gheorghe, Liana; Iacob, Speranta; Iacob, Razvan; Dumbrava, Mona; Becheanu, Gabriel; Herlea, Vlad; Gheorghe, Cristian; Lupescu, Ioana; Popescu, Irinel

2009-12-01

Small nodules (under 3 cm) detected on ultrasound (US) in cirrhotics represent the most challenging category for noninvasive diagnosis of hepatocellular carcinoma (HCC). To evaluate real-time sonoelastography as a noninvasive tool for the diagnosis of small HCC nodules in cirrhotic patients. 42 cirrhotic patients with 58 nodules (1-3 cm) were evaluated with real-time elastography (Hitachi EUB-6500); the mean intensity of colors red, blue, green were measured using a semi-quantitative method. Analysis of histograms for each color of the sonoelastography images was performed for quantifying the elasticity of nodule tissue in comparison with the cirrhotic liver tissue. AUROC curves were constructed to define the best cut-off points to distinguish malignant features of the nodules. Univariate and multivariate logistic regression analysis was performed. 595 sonoelastography images from 42 patients (25 men; 17 women) were analyzed. The mean age was 56.4 +/- 0.7 years and 69% patients were in Child-Pugh class A, 19% class B, 11% class C. For the mean intensity of green color AUROC=0.81, a cut-off value under 108.7 being diagnostic for HCC with a Sp=91.1%, Se=50%, PPV=92.1%, NPV=47.1%. Mean intensity of blue color proved to be an excellent diagnostic tool for HCC (AUROC=0.94); for a cut-off value greater than 128.9, Sp=92.2%, Se=78.9%, PPV=95.4%, NPV=68%. Independent predictive factors of HCC for a small nodule in cirrhotic patients were: blue color over 128.9 at sonoelastography and hypervascular appearance at Doppler US. US elastography is a promising method for the non-invasive diagnosis of early HCC. Blue color at elastography and hypervascular aspects are independent predictors of HCC.

Effect of ball geometry on endurance limit in bending of drilled balls

NASA Technical Reports Server (NTRS)

Munson, H. E.

1975-01-01

Four designs of drilled (cylindrically hollow) balls were tested for resistance to bending fatigue. Bending fatigue has been demonstrated to be a limiting factor in previous evaluations of the drilled ball concept. A web reinforced drilled ball was most successful in resisting bending fatigue. Another design of through drilled design, involving a heavier wall than the standard reference ball, also showed significant improvement in resistance to bending fatigue.

A kicking simulator to investigate the foot-ball interaction during a rugby place kick.

PubMed

Minnaar, Nick; van den Heever, Dawie J

2015-01-01

Foot-ball interaction is an important aspect in rugby place kicking but has received very little attention in literature. This preliminary study presents an adjustable mechanical kicking simulator used to investigate different foot positions and orientations during the foot-ball interaction on resultant ball motion. It was found that changes in foot position and orientation during ball contact can have a large influence on ball motion. It is believed that with further research an optimal place-kicking technique can be found to maximize energy transfer to the ball while still maintaining accuracy.

Ceramic Rail-Race Ball Bearings

NASA Technical Reports Server (NTRS)

Balzer, Mark A.; Mungas, Greg S.; Peters, Gregory H.

2010-01-01

Non-lubricated ball bearings featuring rail races have been proposed for use in mechanisms that are required to function in the presence of mineral dust particles in very low-pressure, dry environments with extended life. Like a conventional ball bearing, the proposed bearing would include an inner and an outer ring separated by balls in rolling contact with the races. However, unlike a conventional ball bearing, the balls would not roll in semi-circular or gothic arch race grooves in the rings: instead, the races would be shaped to form two or more rails (see figure). During operation, the motion of the balls would push dust particles into the spaces between the rails where the particles could not generate rolling resistance for the balls

Effect of panel shape of soccer ball on its flight characteristics

PubMed Central

Hong, Sungchan; Asai, Takeshi

2014-01-01

Soccer balls are typically constructed from 32 pentagonal and hexagonal panels. Recently, however, newer balls named Cafusa, Teamgeist 2, and Jabulani were respectively produced from 32, 14, and 8 panels with shapes and designs dramatically different from those of conventional balls. The newest type of ball, named Brazuca, was produced from six panels and will be used in the 2014 FIFA World Cup in Brazil. There have, however, been few studies on the aerodynamic properties of balls constructed from different numbers and shapes of panels. Hence, we used wind tunnel tests and a kick-robot to examine the relationship between the panel shape and orientation of modern soccer balls and their aerodynamic and flight characteristics. We observed a correlation between the wind tunnel test results and the actual ball trajectories, and also clarified how the panel characteristics affected the flight of the ball, which enabled prediction of the trajectory. PMID:24875291

Performance of 75-millimeter-bore bearings using electron-beam-welded hollow balls with a diameter ratio of 1.26

NASA Technical Reports Server (NTRS)

Coe, H. H.; Parker, R. J.; Scibbe, H. W.

1975-01-01

An experimental investigation was performed to determine the rolling element fatigue life of electron beam-welded hollow balls with a diameter ratio (o.d./i.d.) of 1.26 and to determine the operating characteristics of bearings using these hollow balls. Similar bearings with solid balls were also tested and the data compared. The bearings were operated at shaft speeds up to 28,000 rpm with a thrust load of 2200 N (500 lb). Ball failures during the bearing tests were due to flexure fatigue. The solid and hollow ball bearings tested showed little difference in outer race temperatures and indicated the same bearing torque. The 17.5-mm (0.6875-in.) diameter balls were also tested in the five-ball fatigue tester and showed no significant difference in life when compared with the life of a solid ball.

Effect of panel shape of soccer ball on its flight characteristics

NASA Astrophysics Data System (ADS)

Hong, Sungchan; Asai, Takeshi

2014-05-01

Soccer balls are typically constructed from 32 pentagonal and hexagonal panels. Recently, however, newer balls named Cafusa, Teamgeist 2, and Jabulani were respectively produced from 32, 14, and 8 panels with shapes and designs dramatically different from those of conventional balls. The newest type of ball, named Brazuca, was produced from six panels and will be used in the 2014 FIFA World Cup in Brazil. There have, however, been few studies on the aerodynamic properties of balls constructed from different numbers and shapes of panels. Hence, we used wind tunnel tests and a kick-robot to examine the relationship between the panel shape and orientation of modern soccer balls and their aerodynamic and flight characteristics. We observed a correlation between the wind tunnel test results and the actual ball trajectories, and also clarified how the panel characteristics affected the flight of the ball, which enabled prediction of the trajectory.

Visualization of air flow around soccer ball using a particle image velocimetry

PubMed Central

Hong, Sungchan; Asai, Takeshi; Seo, Kazuya

2015-01-01

A traditional soccer ball is constructed using 32 pentagonal and hexagonal panels. In recent years, however, the likes of the Teamgeist and Jabulani balls, constructed from 14 and 8 panels, respectively, have entered the field, marking a significant departure from conventionality in terms of shape and design. Moreover, the recently introduced Brazuca ball features a new 6-panel design and has already been adopted by many soccer leagues. However, the shapes of the constituent panels of these balls differ substantially from those of conventional balls. Therefore, this study set out to investigate the flight and aerodynamic characteristics of different orientations of the soccer ball, which is constructed from panels of different shapes. A wind tunnel test showed substantial differences in the aerodynamic forces acting on the ball, depending on its orientation. Substantial differences were also observed in the aerodynamic forces acting on the ball in different directions, corresponding to its orientation and rotation. Moreover, two-dimensional particle image velocimetry (2D-PIV) measurements showed that the boundary separation varies depending on the orientation of the ball. Based on these results, we can conclude that the shape of the panels of a soccer ball substantially affects its flight trajectory. PMID:26446616

Visualization of air flow around soccer ball using a particle image velocimetry

NASA Astrophysics Data System (ADS)

Hong, Sungchan; Asai, Takeshi; Seo, Kazuya

2015-10-01

A traditional soccer ball is constructed using 32 pentagonal and hexagonal panels. In recent years, however, the likes of the Teamgeist and Jabulani balls, constructed from 14 and 8 panels, respectively, have entered the field, marking a significant departure from conventionality in terms of shape and design. Moreover, the recently introduced Brazuca ball features a new 6-panel design and has already been adopted by many soccer leagues. However, the shapes of the constituent panels of these balls differ substantially from those of conventional balls. Therefore, this study set out to investigate the flight and aerodynamic characteristics of different orientations of the soccer ball, which is constructed from panels of different shapes. A wind tunnel test showed substantial differences in the aerodynamic forces acting on the ball, depending on its orientation. Substantial differences were also observed in the aerodynamic forces acting on the ball in different directions, corresponding to its orientation and rotation. Moreover, two-dimensional particle image velocimetry (2D-PIV) measurements showed that the boundary separation varies depending on the orientation of the ball. Based on these results, we can conclude that the shape of the panels of a soccer ball substantially affects its flight trajectory.

Reexamination of Ball-Race Conformity Effects on Ball Bearing Life

NASA Technical Reports Server (NTRS)

Zaretsky, Erwin V.; Poplawski, Joseph V.; Root, Lawrence E.

2007-01-01

The analysis in this report considers the life of the ball set as well as the respective lives of the races to reassess the effect of ball-race conformity on ball bearing life. The related changes in ball bearing life are incorporated in life factors that can be used to modify the bearing predicted life using the Lundberg-Palmgren equations and the ANSI/ABMA and ISO Standards. Two simple algebraic relationships were established to calculate life factors LF(sub c) to determine the effect of inner- and outer-race conformity combinations on bearing L(sub 10) life for deepgroove and angular-contact ball bearings, respectively. Depending on the bearing type and series as well as conformity combinations, the calculated life for deep-groove ball bearings can be over 40 percent less than that calculated by the Lundberg-Palmgren equations. For angular-contact ball bearings, the life can vary between +16 and -39 percent from that calculated by the Lundberg-Palmgren equations. Comparing the two ball bearing types, the life factors LF(sub c) for the deep-groove bearings can be as much as 40 percent lower than that for angular-contact ball bearings.

Ceramic ball grid array package stress analysis

NASA Astrophysics Data System (ADS)

Badri, S. H. B. S.; Aziz, M. H. A.; Ong, N. R.; Sauli, Z.; Alcain, J. B.; Retnasamy, V.

2017-09-01

The ball grid array (BGA), a form of chip scale package (CSP), was developed as one of the most advanced surface mount devices, which may be assembled by an ordinary surface ball bumps are used instead of plated nickel and gold (Ni/Au) bumps. Assembly and reliability of the BGA's printed circuit board (PCB), which is soldered by conventional surface mount technology is considered in this study. The Ceramic Ball Grid Array (CBGA) is a rectangular ceramic package or square-shaped that will use the solder ball for external electrical connections instead of leads or wire for connections. The solder balls will be arranged in an array or grid at the bottom of the ceramic package body. In this study, ANSYS software is used to investigate the stress on the package for 2 balls and 4 balls of the CBGA package with the various force range of 1-3 Newton applied to the top of the die, top of the substrate and side of the substrate. The highest maximum stress was analyzed and the maximum equivalent stress was observed on the solder ball and the die. From the simulation result, the CBGA package with less solder balls experience higher stress compared to the package with many solder balls. Therefore, less number of solder ball on the CBGA package results higher stress and critically affect the reliability of the solder balls itself, substrate and die which can lead to the solder crack and also die crack.

A general theory for ball lightning structure and light output

NASA Astrophysics Data System (ADS)

Morrow, R.

2018-03-01

A general theory for free-floating ball lightning is presented which unifies the phantom plasma ball theory involving the production of very little light, with theories for ball lightning involving light output produced by burning particles from the soil. The mechanism for the formation of plasma balls is shown to be quite general, producing very similar plasma balls independent of initial ion densities over four orders of magnitude. All that is required is an excess of positive ions in the initial ball of ions. The central plasma density after 1 s is shown to be the reciprocal of the ion neutralization coefficient for all cases, both analytically and computationally. Further, the plasma region has zero electric field in all cases. Surrounding the plasma ball is a sphere of positive ions moving away from the centre via their own space-charge field; this space-charge field, which is the same in all cases near the plasma ball, drives negative ions and negative particles towards the plasma centre. The connection with burning particle theories is the proposition that the burning particles are highly-charged which is very likely after a lightning strike. Burning negatively charged particles would be driven into the plasma ball region and trapped while any positively charged particles would be driven away. The plasma ball structure is shown to last more than 10 s and the ‘burnout time’ for a typical coal particle (as an example) has been measured at 5-10 s this is comparable with the lifetimes observed for ball lightning. The light output from a few hundred particles is estimated to be ~1 W, a typical output for ball lightning. Finally, suggestions are made for the generation of ball lightning in the laboratory.

The Head Tracks and Gaze Predicts: How the World’s Best Batters Hit a Ball

PubMed Central

Mann, David L.; Spratford, Wayne; Abernethy, Bruce

2013-01-01

Hitters in fast ball-sports do not align their gaze with the ball throughout ball-flight; rather, they use predictive eye movement strategies that contribute towards their level of interceptive skill. Existing studies claim that (i) baseball and cricket batters cannot track the ball because it moves too quickly to be tracked by the eyes, and that consequently (ii) batters do not – and possibly cannot – watch the ball at the moment they hit it. However, to date no studies have examined the gaze of truly elite batters. We examined the eye and head movements of two of the world’s best cricket batters and found both claims do not apply to these batters. Remarkably, the batters coupled the rotation of their head to the movement of the ball, ensuring the ball remained in a consistent direction relative to their head. To this end, the ball could be followed if the batters simply moved their head and kept their eyes still. Instead of doing so, we show the elite batters used distinctive eye movement strategies, usually relying on two predictive saccades to anticipate (i) the location of ball-bounce, and (ii) the location of bat-ball contact, ensuring they could direct their gaze towards the ball as they hit it. These specific head and eye movement strategies play important functional roles in contributing towards interceptive expertise. PMID:23516460

Optical and Acoustic Sensor-Based 3D Ball Motion Estimation for Ball Sport Simulators †.

PubMed

Seo, Sang-Woo; Kim, Myunggyu; Kim, Yejin

2018-04-25

Estimation of the motion of ball-shaped objects is essential for the operation of ball sport simulators. In this paper, we propose an estimation system for 3D ball motion, including speed and angle of projection, by using acoustic vector and infrared (IR) scanning sensors. Our system is comprised of three steps to estimate a ball motion: sound-based ball firing detection, sound source localization, and IR scanning for motion analysis. First, an impulsive sound classification based on the mel-frequency cepstrum and feed-forward neural network is introduced to detect the ball launch sound. An impulsive sound source localization using a 2D microelectromechanical system (MEMS) microphones and delay-and-sum beamforming is presented to estimate the firing position. The time and position of a ball in 3D space is determined from a high-speed infrared scanning method. Our experimental results demonstrate that the estimation of ball motion based on sound allows a wider activity area than similar camera-based methods. Thus, it can be practically applied to various simulations in sports such as soccer and baseball.

Design and validation of the Grip-ball for measurement of hand grip strength.

PubMed

Jaber, Rana; Hewson, David J; Duchêne, Jacques

2012-11-01

The Grip-ball is a new dynamometer used to evaluate grip strength, as well as for use in home-based rehabilitation of the hand and forearm. The Grip-ball consists of pressure and temperature sensors and an electronic wireless communication system contained in an airtight ball. That can be inflated to different pressures. The device has advantages over standard dynamometers in that it looks like a simple ball, and can wirelessly communicate via Bluetooth to any compatible receiver, thus have potential to be used for clinical assessment and rehabilitation in a remote setting. The reliability and reproducibility of the device were assessed for the pressure sensor itself, as well as the relationship between the force applied and the pressure measured by the Grip-ball. The initial validation was performed using the pressure sensor without the ball in order to confirm the accuracy of the sensor used. A second validation study was conducted using the Grip-ball rather than just its sensor to examine the relationship between the pressure measured inside the ball and force applied. The results showed that there is a very good correlation (r=0.997, p<0.05) between the pressure measured by the Grip-ball sensor and that measured by a Vigorimeter, thus confirming the reliability of the sensor used in the Grip-ball. A quadratic regression equation was calculated in order to predict the force applied based on the pressure measured inside the ball, and the initial pressure to which the ball was inflated (R(2)=0.97, standard error 10.9N). Such a finding compares favourably with the variability inherent in Jamar recordings, thus indicating that the Grip-ball could be used to assess grip force. An industrial version of the Grip-ball, which is currently under development, will be able to be used for the entire range of grip force in the population. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

Effects of turbulence on the drag force on a golf ball

NASA Astrophysics Data System (ADS)

Cross, Rod

2016-09-01

Measurements are presented of the drag force on a golf ball dropped vertically into a tank of water. As observed previously in air, the drag coefficient drops sharply when the flow becomes turbulent. The experiment would be suitable for undergraduate students since it can be undertaken at low ball speeds and since the effects of turbulence are easily observed on video film. A modified golf ball was used to show how a ball with a smooth and a rough side, such as a cricket ball, is subject to a side force when the ball surface itself is asymmetrical in the transverse direction.

Evaluation of drilled-ball bearings at DN values to three million. 1: Variable oil flow tests

NASA Technical Reports Server (NTRS)

Holmes, P. W.

1932-01-01

Two 125-mm-bore solid ball bearings and two similar drilled ball bearings were operated at speeds up to 24,000 rpm (3.0 million DN) with a 13,000 newton (3000 lb) thrust load. The oil flow rate was varied from 0.045 to 0.121 kilograms per second (6 to 16 lb/min). The solid ball bearings operated satisfactorily over the entire range of conditions. The drilled ball bearing experienced cage rub with marginal lubrication at 0.045 kilograms per second (6 lb/min). The drilled ball bearing generally ran cooler than the solid ball bearings.

Design and Testing of UMM Vertical Ball Mill (UVBM) for producing Aluminium Powder

NASA Astrophysics Data System (ADS)

Aisyah, I. S.; Caesarendra, Wahyu; Suprihanto, Agus

2018-04-01

UMM Vertical Ball Mill (UVBM) was intended to be the apparatus to produce metal powder with superior characteristic in production rate while retaining good quality of metal powder. The concept of design was adopting design theory of Phal and Beitz with emphasis on increasing of probability of success in engineering and economy aspects.Since it was designed as vertical ball mill, a new way to produce powder, then it need to be tested for the performance after manufactured. The test on UVBM was carried out by milling of aluminium chip for 5 (five) different milling time of 0.5 hours, 1 hour, 3 hours, 5 hours and 7 hours, and the powder product then be characterized for it morphology and size using Scanning Electron Microscope (SEM) and Sieve.The results of the study were the longer of the milling time, the finer of the powder. From the test results of SEM, the morphology of the powder with 5 variations of milling time were most of the powder in form of flake (flat), small round and angular (irregular). The distribution of powder size was best obtained on the variation of milling time 3 hours, 5 hours, and 7 hours with percentage of 200 mesh in size of 22.14 %, 64 % and 91.25 % respectively.

On the origin of the drag force on golf balls

NASA Astrophysics Data System (ADS)

Balaras, Elias; Beratlis, Nikolaos; Squires, Kyle

2017-11-01

It is well establised that dimples accelerate the drag-crisis on a sphere. The result of the early drag-crisis is a reduction of the drag coefficient by more than a factor of two when compared to a smooth sphere at the same Reynolds number. However, when the drag coefficients for smooth and dimpled spheres in the supercritical regime are compared, the latter is higher by a factor of two to three. To understand the origin of this behavior we conducted direct numerical simulations of the flow around a dimpled sphere, which is similar to commercially available golf balls, in the supercritical regime. By comparing the results to those for a smooth sphere it is found that dimples, although effective in accelerating the drag crisis, impose a local drag-penalty, which contributes significantly to the overall drag force. This finding challenges the broadly accepted view, that the dimples only indirectly affect the drag force on a golf ball by manipulating the structure of the turbulent boundary layer near the wall and consequently affect global separation. Within this view, typically the penalty on the drag force imposed by the dimples is assumed to be small and coming primarily from skin friction. The direct numerical simulations we will report reveal a very different picture.

Formulation of a dry powder influenza vaccine for nasal delivery.

PubMed

Garmise, Robert J; Mar, Kevin; Crowder, Timothy M; Hwang, C Robin; Ferriter, Matthew; Huang, Juan; Mikszta, John A; Sullivan, Vincent J; Hickey, Anthony J

2006-03-10

The purpose of this research was to prepare a dry powder vaccine formulation containing whole inactivated influenza virus (WIIV) and a mucoadhesive compound suitable for nasal delivery. Powders containing WIIV and either lactose or trehalose were produced by lyophilization. A micro-ball mill was used to reduce the lyophilized cake to sizes suitable for nasal delivery. Chitosan flakes were reduced in size using a cryo-milling technique. Milled powders were sieved between 45 and 125 microm aggregate sizes and characterized for particle size and distribution, morphology, and flow properties. Powders were blended in the micro-ball mill without the ball. Lyophilization followed by milling produced irregularly shaped, polydisperse particles with a median primary particle diameter of approximately 21 microm and a yield of approximately 37% of particles in the 45 to 125 microm particle size range. Flow properties of lactose and trehalose powders after lyophilization followed by milling and sieving were similar. Cryo-milling produced a small yield of particles in the desired size range (<10%). Lyophilization followed by milling and sieving produced particles suitable for nasal delivery with different physicochemical properties as a function of processing conditions and components of the formulation. Further optimization of particle size and morphology is required for these powders to be suitable for clinical evaluation.

Why bigger may in fact be better... in the context of table tennis

NASA Astrophysics Data System (ADS)

Truscott, Tadd; Pan, Zhao; Belden, Jesse

2014-11-01

We submit that table tennis is too fast. Because of the high ball velocities relative to the small table size, players are required to act extremely quickly, often exceeding the limits of human reaction time. Additionally, the Magnus effect resulting from large rotation rates introduces dramatically curved paths and causes rapid direction changes after striking the table or paddle, which effectively reduces reaction time further. Moreover, watching a professional game is often uninteresting and even tiring because the ball is moving too quickly to follow with the naked eye and the action of the players is too subtle to resolve from a distance. These facts isolate table tennis from our quantitatively defined ``fun game club,'' and make it less widely appealing than sports like baseball and soccer. Over the past 100 years, the rules of table tennis have changed several times in an effort to make the game more attractive to players and spectators alike, but the game continues to lose popularity. Here, we experimentally quantify the historic landmark equipment changes of table tennis from a fluid dynamics perspective. Based on theory and observation, we suggest a larger diameter ball for table tennis to make the game more appealing to both spectators and amateur players.

Effects of 12-week on-field combined strength and power training on physical performance among U-14 young soccer players.

PubMed

Wong, Pui-lam; Chamari, Karim; Wisløff, Ulrik

2010-03-01

This study examined the effects of on-field combined strength and power training (CSPT) on physical performance among U-14 young soccer players. Players were assigned to experimental (EG, n = 28) and control groups (CG, n = 23). Both groups underwent preseason soccer training for 12 weeks. EG performed CSPT twice a week, which consisted of strength and power exercises that trained the major muscles of the core, upper, and lower body. CSPT significantly (p < 0.05) improved vertical jump height, ball-shooting speed, 10 m and 30 m sprint times, Yo-Yo intermittent endurance run (YYIER), and reduced submaximal running cost (RC). CSPT had moderate effect on vertical jump, ball-shooting, 30 m sprint, and YYIER, small effect on 10 m sprint, RC, and maximal oxygen uptake. YYIER had significant (p < 0.05) correlations with 10 m (r = -0.47) and 30 m (r = -0.43) sprint times, ball-shooting speed (r = 0.51), and vertical jump (r = 0.34). The CSPT can be performed together with soccer training with no concomitant interference on aerobic capacity and with improved explosive performances. In addition, it is suggested that CSPT be performed during the preseason period rather than in-season to avoid insufficient recovery/rest or overtraining.

Survival of Serratia marcescens in benzalkonium chloride and in multiple-dose medication vials: relationship to epidemic septic arthritis.

PubMed Central

Nakashima, A K; Highsmith, A K; Martone, W J

1987-01-01

In an epidemic of septic arthritis due to Serratia marcescens, the intra-articular injection of contaminated methylprednisolone may have played a key role. The epidemic strain was found in used multiple-dose vials of methylprednisolone and in a canister of cotton balls soaked in benzalkonium chloride. The cotton balls had been used for antisepsis and disinfection. Growth characteristics of the epidemic strain of S. marcescens were compared with those of control strains of S. marcescens which had been obtained from unrelated nosocomial outbreaks. The epidemic strain was able to survive in 1:100 dilutions of benzalkonium chloride and was able to grow to greater than 10(5) CFU/ml in multiple-dose vials of methylprednisoline; control strains could not be recovered after 24 h in the same solutions. The preservative in methylprednisolone is gamma-myristyl picolinium chloride, a compound chemically related to benzalkonium chloride. We speculate that the epidemic strain of S. marcescens, which was resistant to benzalkonium chloride, had cross-resistance to gamma-myristyl picolinium chloride. If the cotton balls were used to disinfect the tops of the multiple-dose vials of methylprednisolone, small numbers of organisms subsequently introduced into the solution could have grown to high concentrations. PMID:3298309

Iron-Nickel Meteorite Zapped by Mars Rover Laser

NASA Image and Video Library

2016-11-02

The dark, golf-ball-size object in this composite, colorized view from the Chemistry and Camera (ChemCam) instrument on NASA's Curiosity Mars rover shows a grid of shiny dots where ChemCam had fired laser pulses used for determining the chemical elements in the target's composition. The analysis confirmed that this object, informally named "Egg Rock," is an iron-nickel meteorite. Iron-nickel meteorites are a common class of space rocks found on Earth, and previous examples have been found on Mars, but Egg Rock is the first on Mars to be examined with a laser-firing spectrometer. The laser pulses on Oct. 30, 2016, induced bursts of glowing gas at the target, and ChemCam's spectrometer read the wavelengths of light from those bursts to gain information about the target's composition. The laser pulses also burned through the dark outer surface, exposing bright interior material. This view combines two images taken later the same day by ChemCam's remote micro-imager (RMI) camera, with color added from an image taken by Curiosity's Mast Camera (Mastcam). A Mastcam image of Egg Rock is at PIA21134. http://photojournal.jpl.nasa.gov/catalog/PIA21133

When red lights look yellow.

PubMed

Wood, Joanne M; Atchison, David A; Chaparro, Alex

2005-11-01

Red signals are typically used to signify danger. This study was conducted to investigate a situation identified by train drivers in which red signals appear yellow when viewed at long distances (approximately 900 m) through progressive-addition lenses. A laboratory study was conducted to investigate the effects of defocus, target size, ambient illumination, and surround characteristics on the extent of the color misperception of train signals by nine visually normal participants. The data from the laboratory study were validated in a field study by measuring the amounts of defocus and the distances at which the misperception of the color of train signals was apparent and whether these distances varied as a function of time of day. The laboratory study demonstrated that small red targets (approximately 1 min arc) can appear yellow when viewed through small amounts of defocus (approximately +0.75 D) under bright illumination (1910 cd/m(2)). In the field study, the defocus needed to produce the color misperception was similar to that found in the laboratory study. Time of day affected the color misperception, and there was no misperception at night. The color misperception is not solely associated with progressive-addition lenses, but occurs in the presence of small amounts of positive defocus. The potential for the misperception to result in collisions and fatalities presents a major safety concern.

Bilateral periorbital necrotizing fasciitis following exposure to Holi colors: A case report

PubMed Central

Arora, Ritu; Das, Sima; Shroff, Daraius; Narula, Ritesh

2007-01-01

Holi festival is celebrated in India traditionally by applying colors on one another. Various ocular adverse effects of these colors have been reported including conjunctivitis and corneal abrasion. We report a case of bilateral periorbital necrotizing fasciitis, following exposure to Holi colors. General physicians might encounter more such cases after exposure to Holi colors. In India, these colors are prepared on a small scale and lack any quality checks. Use of such toxic colors should be discouraged, and all doctors should caution people against using synthetic dyes. This case report highlights the need to put manufacturing of Holi colors under guidelines of the Food and Drug Cosmetic Act and the Bureau of Indian Standards. PMID:17699947

Accuracy and Reliability of a New Tennis Ball Machine

PubMed Central

Brechbuhl, Cyril; Millet, Grégoire; Schmitt, Laurent

2016-01-01

The aim was to evaluate the reliability of a newly-developed ball machine named 'Hightof', on the field and to assess its accuracy. The experiment was conducted in the collaboration of the 'Hawk-Eye' technology. The accuracy and reliability of this ball machine were assessed during an incremental test, with 1 min of exercise and 30 sec of recovery, where the frequency of the balls increased from 10 to 30 balls·min-1. The initial frequency was 10 and increased by 2 until 22, then by 1 until 30 balls·min-1. The reference points for the impact were 8.39m from the net and 2.70m from lateral line for the right side and 2.83m for the left side. The precision of the machine was similar on the right and left sides (0.63 ± 0.39 vs 0.63 ± 0.34 m). The distances to the reference point were 0.52 ± 0.42, 0.26 ± 0.19, 0.52 ± 0.37, 0.28 ± 0.19 m for the Y-right, X-right, Y-left and X-left impacts. The precision was constant and did not increase with the intensity. (e.g ball frequency). The ball velocity was 86.3 ± 1.5 and 86.5 ± 1.3 km·h-1 for the right and the left side, respectively. The coefficient of variation for the velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min-1). Conclusion: both the accuracy and the reliability of this new ball machine appear satisfying enough for field testing and training. Key points The reliability and accuracy of a new ball machine named 'Hightof' were assessed. The impact point was reproducible and similar on the right and left sides (±0.63 m). The precision was constant and did not increase with the intensity (e.g ball frequency). The coefficient of variation of the ball velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min-1). PMID:27274663

Accuracy and Reliability of a New Tennis Ball Machine.

PubMed

Brechbuhl, Cyril; Millet, Grégoire; Schmitt, Laurent

2016-06-01

The aim was to evaluate the reliability of a newly-developed ball machine named 'Hightof', on the field and to assess its accuracy. The experiment was conducted in the collaboration of the 'Hawk-Eye' technology. The accuracy and reliability of this ball machine were assessed during an incremental test, with 1 min of exercise and 30 sec of recovery, where the frequency of the balls increased from 10 to 30 balls·min(-1). The initial frequency was 10 and increased by 2 until 22, then by 1 until 30 balls·min(-1). The reference points for the impact were 8.39m from the net and 2.70m from lateral line for the right side and 2.83m for the left side. The precision of the machine was similar on the right and left sides (0.63 ± 0.39 vs 0.63 ± 0.34 m). The distances to the reference point were 0.52 ± 0.42, 0.26 ± 0.19, 0.52 ± 0.37, 0.28 ± 0.19 m for the Y-right, X-right, Y-left and X-left impacts. The precision was constant and did not increase with the intensity. (e.g ball frequency). The ball velocity was 86.3 ± 1.5 and 86.5 ± 1.3 km·h(-1) for the right and the left side, respectively. The coefficient of variation for the velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min(-1)). both the accuracy and the reliability of this new ball machine appear satisfying enough for field testing and training. Key pointsThe reliability and accuracy of a new ball machine named 'Hightof' were assessed.The impact point was reproducible and similar on the right and left sides (±0.63 m).The precision was constant and did not increase with the intensity (e.g ball frequency).The coefficient of variation of the ball velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min(-1)).

Ball clay

USGS Publications Warehouse

Virta, R.L.

2001-01-01

Part of the 2000 annual review of the industrial minerals sector. A general overview of the ball clay industry is provided. In 2000, sales of ball clay reached record levels, with sanitary ware and tile applications accounting for the largest sales. Ball clay production, consumption, prices, foreign trade, and industry news are summarized. The outlook for the ball clay industry is also outlined.

A Comparative Study of Two Types of Ball-on-Ball Collision

ERIC Educational Resources Information Center

White, Colin

2017-01-01

This paper describes three methods of measuring the coefficient of restitution (CoR) for two different types of ball-on-ball collision. The first collision type (for which two different CoR measurement procedures are described) is a static, hanging steel ball forming part of a Newton's cradle arrangement, which is then hit by its adjacent…

Systematic study of Zc+ family from a multiquark color flux-tube model

NASA Astrophysics Data System (ADS)

Deng, Chengrong; Ping, Jialun; Huang, Hongxia; Wang, Fan

2015-08-01

Inspired by the present experimental results of charged charmonium-like states Zc+, we present a systematic study of the tetraquark states [c u ][c ¯ d ¯ ] in a color flux-tube model with a multibody confinement potential. Our investigation indicates that charged charmonium-like states Zc+(3900 ) or Zc+(3885 ), Zc+(3930 ) , Zc+(4020 ) or Zc+(4025 ), Z1+(4050 ), Z2+(4250 ), and Zc+(4200 ) can be described as a family of tetraquark [c u ][c ¯d ¯] states with the quantum numbers n 2SL+1 J and JP of 1 3S1 and 1+, 2 3S1 and 1+, 1 5S2 and 2+, 1 3P1 and 1-, 1 5D1 and 1+, and 1 3D1 and 1+, respectively. The predicted lowest mass charged tetraquark state [c u ][c ¯ d ¯ ] with 0+ and 1 1S0 lies at 3780 ±10 MeV /c2 in the model. These tetraquark states have compact three-dimensional spatial configurations similar to a rugby ball with higher orbital angular momentum L between the diquark [c u ] and antidiquark [c ¯d ¯] corresponding to a more prolate spatial distribution. The multibody color flux tube, a collective degree of freedom, plays an important role in the formation of those charged tetraquark states. However, the two heavier charged states Zc+(4430 ) and Zc+(4475 ) cannot be explained as tetraquark states [c u ][c ¯d ¯] in this model approach.

Ban Deodorant Ball Mortar.

ERIC Educational Resources Information Center

Carpenter, D. Rae, Jr.; And Others

1988-01-01

Discusses a demonstration of vertical collision of two balls. Shows the theoretical height ratio using mathematical expression and diagrams. Compares it with researchers' experimental results. Expands the two-ball collision to multi-ball system. (YP)

Morphological and XPS study of ball milled Fe1-xAlx (0.3≤x≤0.6) alloys

NASA Astrophysics Data System (ADS)

Rajan, Sandeep; Kumar, Anil; Vyas, Anupam; Brajpuriya, Ranjeet

2018-05-01

The paper presents mechanical and XPS study of ball milled Fe1-xAlx (0.3≤x≤0.6) alloys. The author prepared the solid solution of Fe(Al) with different composition of Al by using mechanical alloying (MA) technique. The MA process induces a progressive dissolution of Al into Fe, resulted in the formation of an extended Fe(Al) solid solution with the bcc structure after 5 hr of milling. The SEM Images shows that the initial shape of particles disappeared completely, and their structure became a mixture of small and large angular-shaped crystallites with different sizes. The TEM micrograph also confirms the reduction in crystallite size and alloy formation. XPS study shows the shift in the binding energy position of both Fe and Al Peaks provide strong evidence of Fe(Al) phase formation after milling.

Collective effects and dynamics of non-adiabatic flame balls

NASA Astrophysics Data System (ADS)

D'Angelo, Yves; Joulin, Guy

2001-03-01

The dynamics of a homogeneous, polydisperse collection of non-adiabatic flame balls (FBs) is investigated by analytical/numerical means. A strongly temperature-dependent Arrhenius reaction rate is assumed, along with a light enough reactant characterized by a markedly less than unity Lewis number (Le). Combining activation-energy asymptotics with a mean-field type of treatment, the analysis yields a nonlinear integro-differential evolution equation (EE) for the FB population. The EE accounts for heat losses inside each FB and unsteadiness around it, as well as for its interactions with the entire FB population, namely mutual heating and faster (Le<1) consumption of the reactant pool. The initial FB number density and size distribution enter the EE explicitly. The latter is studied analytically at early times, then for small total FB number densities; it is subsequently solved numerically, yielding the whole population evolution and its lifetime. Generalizations and open questions relating to `spotty' turbulent combustion are finally evoked.

Mechanical design and analysis of focal plate for gravity deformation

NASA Astrophysics Data System (ADS)

Wang, Jianping; Chu, Jiaru; Hu, Hongzhuan; Li, Kexuan; Zhou, Zengxiang

2014-07-01

The surface accuracy of astronomical telescope focal plate is a key indicator to precision stellar observation. To conduct accurate deformation measurement for focal plate in different status, a 6-DOF hexapod platform was used for attitude adjustment. For the small adjustment range of a classic 6-DOF hexapod platform, an improved structural arrangement method was proposed in the paper to achieve ultimate adjustment of the focal plate in horizontal and vertical direction. To validate the feasibility of this method, an angle change model which used ball hinge was set up for the movement and base plate. Simulation results in MATLAB suggested that the ball hinge angle change of movement and base plate is within the range of the limiting angle in the process of the platform plate adjusting to ultimate attitude. The proposed method has some guiding significance for accurate surface measurement of focal plate.

Processing and Characterization of Fe-Mn-Cu-Sn-C Alloys Prepared by Ball Milling and Spark Plasma Sintering

NASA Astrophysics Data System (ADS)

Bączek, Elżbieta; Konstanty, Janusz; Romański, Andrzej; Podsiadło, Marcin; Cyboroń, Jolanta

2018-03-01

In this work, Fe-Mn-Cu-Sn-C alloys were prepared by means of powder metallurgy (PM). Powder mixtures were ball-milled for 8, 30 and 120 h and densified to < 1% porosity using spark plasma sintering (SPS) at 900 °C and 35 MPa. After consolidation, all samples of the Fe alloys were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), hardness and flexural strength tests. Resistance to abrasive wear was evaluated in both three-body abrasion and two-body abrasion tests. The SEM observations revealed an evident dependence of grain size and microstructural homogeneity on milling time. The XRD analysis showed a marked increase in austenite content in the as-sintered specimens with milling time. Although the proportion of deformation-induced martensite was small, the strengthening effect of abrasion on the subsurface layer of the investigated alloys was clearly indicated by Knoop hardness measurements.

Laboratory measurements of upwelled radiance and reflectance spectra of Calvert, Ball, Jordan, and Feldspar soil sediments

NASA Technical Reports Server (NTRS)

Whitlock, C. H.; Usry, J. W.; Witte, W. G.; Gurganus, E. A.

1977-01-01

An effort to investigate the potential of remote sensing for monitoring nonpoint source pollution was conducted. Spectral reflectance characteristics for four types of soil sediments were measured for mixture concentrations between 4 and 173 ppm. For measurements at a spectral resolution of 32 mm, the spectral reflectances of Calvert, Ball, Jordan, and Feldspar soil sediments were distinctly different over the wavelength range from 400 to 980 nm at each concentration tested. At high concentrations, spectral differences between the various sediments could be detected by measurements with a spectral resolution of 160 nm. At a low concentration, only small differences were observed between the various sediments when measurements were made with 160 nm spectral resolution. Radiance levels generally varied in a nonlinear manner with sediment concentration; linearity occurred in special cases, depending on sediment type, concentration range, and wavelength.

[Endoscopic diagnosis of local chemical burn of mucous membranes of the stomach, induced with the purpose of simulation of gastric ulcer].

PubMed

Byzov, N V; Plekhanov, V N

2013-01-01

With the purpose of improvement of diagnosis of induced gastric ulcer were examined 11 patients who took aggressive agents for simulation of gastric ulcer and 33 patients who took pseudo-aggressive agents. Observables, conduced diagnosis of local chemical burn of mucous coat of stomach during initial 6 days after taking aggressive agents. Stages of ulcerous process, resulting from local chemical burn of mucous coat of stomach, coressponds to real gactric ulcer. Gelatin capsule using as a container for delivery of aggressive agents, melts in stomach in 5-6 minutes after taking. Independent from body position, mucous coat of greater curvature of the stomach is damaged. It is impossible to simulate duodenal bulb ulcer using the gelatine capsule or ball made of breadcrumb. The last method of delivery of aggressive agent can damage the small intestine because of uncontrollability of the place of breaking the ball.

Rare-earth magnet ingestion: a childhood danger reaches adolescence.

PubMed

Agha, Beesan Shalabi; Sturm, Jesse J; Costello, Brian E

2013-10-01

Ingestion of multiple magnets may cause serious gastrointestinal morbidity, such as pressure necrosis, perforation, fistula formation, or intestinal obstruction due to forceful attraction across bowel wall. Although the consequences of multiple magnet ingestion are well documented in young children, the current popularity of small, powerful rare-earth magnets marketed as "desk toys" has heightened this safety concern in all pediatric age groups. A recent US Consumer Product Safety Commission product-wide warning additionally reports the adolescent practice of using toy high-powered, ball-bearing magnets to simulate tongue and lip piercings, a behavior that may increase risk of inadvertent ingestion. We describe 2 cases of older children (male; aged 10 and 13 years, respectively) with unintentional ingestion of multiple rare-earth magnets. Health care providers should be alerted to the potential for misuse of these high-powered, ball-bearing magnets among older children and adolescents.

Spheres settling in an Oldroyd-B fluid

NASA Astrophysics Data System (ADS)

Pan, Tsorng-Whay; Glowinski, Roland

2017-11-01

In this talk we present a numerical study of the dynamics of balls settling in a vertical channel with a square cross-section filled with an Oldroyd-B fluid. For the case of two balls, two typical kinds of particle dynamics are obtained: (i) periodic interaction between two balls and (ii) the formation of a vertical chain of two balls. For the periodic interaction of two balls occurred at lower values of the elasticity number, two balls draft, kiss and break away periodically and the chain is not formed due to not strong enough elastic force. For slightly higher values of the elasticity number, two balls draft, kiss and break away a couple times first and then form a chain. Such chain finally becomes a vertical one after the oscillation damps out. For higher values of the elasticity number, two balls draft, kiss and form a vertical chain right away. The formation of three ball chain can be obtained at higher values of the elasticity number. This work was supported by NSF (Grant DMS-1418308).

How Cristiano Ronaldo performs his knuckleball?

NASA Astrophysics Data System (ADS)

Cohen, Caroline; Darbois Texier, Baptiste; Quere, David; Clanet, Christophe

2012-11-01

A soccer ball kicked at very low spin can exhibit a zigzag trajectory. Along its straight path, the ball deviates laterally from about 0.2 m, that is to say one ball diameter. One zig zag happens as the ball travelled about 15 m. As the deviation direction seems unpredictable, this effect is highly annoying for goalkeepers. That why Cristiano Ronaldo and many soccer players are looking for this phenomenon. Those trajectories called knuckleballs are also observed on volleyball and baseball. We study experimentally indoor knuckleballs for different balls varying from soccer balls to smooth spheres. We show that knuckle effect doesn't derive from ball deformations at foot impact or ball seams. Actually, aerodynamic lift forces on a smooth sphere are fluctuating and are responsible for knuckleballs. From this study, we deduce side force intensity exerted on smooth spheres and sport balls for typical game Reynolds number (Re ~104 -106). Finally we discuss required conditions to observe a knuckleball on the sport field.

Problems with the Baade-Wesselink method

NASA Technical Reports Server (NTRS)

Bohm-Vitense, E.; Garnavich, P.; Lawler, M.; Mena-Werth, J.; Morgan, S.

1989-01-01

The discrepancy noted in radii obtained by the Baade-Wesselink method when different colors are used to determine the effective temperatures is explored. The discrepancy is found to be due to an inconsistency in the applied temperature-color calibrations. The assumption of the maximum likelihood method that beta (the effective temperature + 0.1 times the bolometric correction) is a linear function of the color is valid for the B-V and V-I colors, but not for the V-R colors. It is suggested that the errors introduced by the nonlinearity in the relation between beta and the V-R colors will produce radii which are too large. The radii derived from the V-B colors appear to be too small.

The Crystal Ball Project: Predicting the Future of Composition and the Preparation of Composition Teachers

ERIC Educational Resources Information Center

Hill, Crag; Ericsson, Patricia Freitag

2014-01-01

In this article the authors peer into current elementary classrooms and college composition courses in 2020 to envision what K-12 and composition curricula can do now to ensure today's students are prepared for those future composition classes. The authors interviewed veteran (20 or more years) K-6 teachers in a small university town and…

Single and combination insecticides evaluated as regulatory immersion treatments to eliminate third-instar Japanese beetle (Coleoptera: Scarabaeidae) from small diameter field-grown and containerized nursery plants

USDA-ARS?s Scientific Manuscript database

Japanese beetles, Popillia japonica Newman, are a nursery regulatory pest. Immersion of field-grown plants harvested as balled and burlapped (B&B) or container plants grown in pine bark substrates in a solution of chlorpyrifos or bifenthrin is allowed for certification in the Domestic Japanese Beet...

NASA-DoD Lead-Free Electronics Project

NASA Technical Reports Server (NTRS)

Kessel, Kurt R.

2009-01-01

The primary technical objective of this project is to undertake comprehensive testing to generate information on failure modes/criteria to better understand the reliability of: (1) Packages (e.g., Thin Small Outline Package [TSOP], Ball Grid Array [BGA], Plastic Dual In-line Package [PDIP]) assembled and reworked with lead-free alloys, (2) Packages (e.g., TSOP, BGA, PDIP) assembled and reworked with mixed (lead/lead-free) alloys.

Game-Based Approaches, Pedagogical Principles and Tactical Constraints: Examining Games Modification

ERIC Educational Resources Information Center

Serra-Olivares, Jaime; García-López, Luis M.; Calderón, Antonio

2016-01-01

The purpose of this study was to analyze the effect of modification strategies based on the pedagogical principles of the Teaching Games for Understanding approach on tactical constraints of four 3v3 soccer small-sided games. The Game performance of 21 U-10 players was analyzed in a game similar to the adult game; one based on keeping-the-ball;…

Analysis of Black Bearing Balls from a Space Shuttle Body Flap Actuator

NASA Technical Reports Server (NTRS)

Sovinski, Marjorie F.; Street, Kenneth W.

2005-01-01

A significantly deteriorated ball bearing mechanism from a body flap actuator on Space Shuttle OV-103 was disassembled and the balls submitted for analysis in conjunction with Return to Flight activities. The OV-103 balls, referred to as the "black balls", were subjected to X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) and Raman micro spectroscopy, surface profilometry, and optical and electron microscopy. The spectroscopic results in combination with microscopy analysis allowed a determination of the lubricant degradation pathway. The chemical attack mechanism does not adequately explain the unique visual appearance of the black balls. Numerous efforts have unsuccessfully focused on duplication of the phenomena causing this unique surface structure and appearance of the black balls. Further detail will be presented supporting these conclusions along with plausible explanations of the unique black appearance to the balls.

Ball mounting fixture for a roundness gage

DOEpatents

Gauler, Allen L.; Pasieka, Donald F.

1983-01-01

A ball mounting fixture for a roundness gage is disclosed. The fixture includes a pair of chuck assemblies oriented substantially transversely with respect to one another and mounted on a common base. Each chuck assembly preferably includes a rotary stage and a wobble plate affixed thereto. A ball chuck affixed to each wobble plate is operable to selectively support a ball to be measured for roundness, with the wobble plate permitting the ball chuck to be tilted to center the ball on the axis of rotation of the rotary stage. In a preferred embodiment, each chuck assembly includes a vacuum chuck operable to selectively support the ball to be measured for roundness. The mounting fixture enables a series of roundness measurements to be taken with a conventional rotating gagehead roundness instrument, which measurements can be utilized to determine the sphericity of the ball.

Measuring the rebound resilience of a bouncing ball

NASA Astrophysics Data System (ADS)

Wadhwa, Ajay

2012-09-01

Some balls which are made of high-quality rubber (an elastomeric) material, such as tennis or squash balls, could be used for the determination of an important property of such materials called resilience. Since a bouncing ball involves a single impact we call this property 'rebound resilience' and express it as the ratio of the rebound height to the initial drop height of the ball. We determine the rebound resilience for three different types of ball by calculating the coefficient of restitution of the ball-surface combination from the experimentally measurable physical quantities, such as initial drop height and time interval between successive bounces. Using these we also determine the contact time of balls with the surface of impact. For measurements we have used audio, motion and surface-temperature sensors that were interfaced through a USB port with a computer.

Influence of mass and volume of ruminal contents on voluntary intake and digesta passage of a forage diet in steers.

PubMed

Schettini, M A; Prigge, E C; Nestor, E L

1999-07-01

To assess the influence of volume and mass of ruminal contents on voluntary intake and related variables, five ruminally cannulated steers (550 kg) were fed a low-quality forage diet (43.1% ADF, 8.1% CP) in a 5 x 5 Latin square experiment. Mass and volume of ruminal contents were altered by adding varying numbers and weights of filled tennis balls (6.7-cm diameter) to the rumen immediately before the initiation of each experimental period. Treatments consisted of 0 balls (control), 50 balls with a 1.1 specific gravity (SG), 100 balls with a 1.1 SG, 50 balls with a 1.3 SG, and 100 balls with a SG of 1.3. The total volume of balls was 7.25 and 14.5 L for 50 and 100 balls, respectively. The total weight of balls was 8.5 and 17 kg for 50 and 100 balls with a 1.1 SG and 10.75 and 21.5 kg for 50 and 100 balls with a 1.3 SG, respectively. Daily DMI was 8.3, 7.3, 7.0, 6.5, and 6.0 kg for control; 50, 1.1 SG; 50, 1.3 SG; 100, 1.1 SG; and 100, 1.3 SG, respectively. Addition of balls to the rumen reduced (P < .01) DMI. Increasing the number (P < .01) and SG (P <. 01) of the balls decreased DMI further. However, digestibilities of DM, NDF, ADF, and CP were not influenced by treatment. Increasing the number of balls in the rumen increased (P < .05) rate of passage of digesta from the rumen, but increasing SG of the balls did not alter rate of passage. There was a treatment x hour interaction (P < .05) in the proportion of ruminal digesta with a functional specific gravity (FSG) less than 1.1, which decreased with time after feeding for the control but increased with time after feeding for other treatments. Ruminal passage rate of inert particles added in the rumen of different SG (1.1 and 1.3) and length (1 and 3 mm) decreased (P < .05) as SG of the balls increased. Mean fecal particle size was greater for those treatments with the heavier balls. Both the number and SG of balls (P < .10) influenced total VFA, and total concentrations were greater for the control and for the 1.1 SG than for the 1.3 SG treatments.

Biomechanical Analysis of Weighted-Ball Exercises for Baseball Pitchers.

PubMed

Fleisig, Glenn S; Diffendaffer, Alek Z; Aune, Kyle T; Ivey, Brett; Laughlin, Walter A

Weighted-ball throwing programs are commonly used in training baseball pitchers to increase ball velocity. The purpose of this study was to compare kinematics and kinetics among weighted-ball exercises with values from standard pitching (ie, pitching standard 5-oz baseballs from a mound). Ball and arm velocities would be greater with lighter balls and joint kinetics would be greater with heavier balls. Controlled laboratory study. Twenty-five high school and collegiate baseball pitchers experienced with weighted-ball throwing were tested with an automated motion capture system. Each participant performed 3 trials of 10 different exercises: pitching 4-, 5-, 6-, and 7-oz baseballs from a mound; flat-ground crow hop throws with 4-, 5-, 6-, and 7-oz baseballs; and flat-ground hold exercises with 14- and 32-oz balls. Twenty-six biomechanical parameters were computed for each trial. Data among the 10 exercises were compared with repeated measures analysis of variance and post hoc paired t tests against the standard pitching data. Ball velocity increased as ball mass decreased. There were no differences in arm and trunk velocities between throwing a standard baseball and an underweight baseball (4 oz), while arm and trunk velocities steadily decreased as ball weight increased from 5 to 32 oz. Compared with values pitching from a mound, velocities of the pelvis, shoulder, and ball were increased for flat-ground throws. In general, as ball mass increased arm torques and forces decreased; the exception was elbow flexion torque, which was significantly greater for the flat-ground holds. There were significant differences in body positions when pitching on the mound, flat-ground throws, and holds. While ball velocity was greatest throwing underweight baseballs, results from the study did not support the rest of the hypothesis. Kinematics and kinetics were similar between underweight and standard baseballs, while overweight balls correlated with decreased arm forces, torques, and velocities. Increased ball velocity and joint velocities were produced with crow hop throws, likely because of running forward while throwing. As pitching slightly underweight and overweight baseballs produces variations in kinematics without increased arm kinetics, these exercises seem reasonable for training pitchers. As flat-ground throwing produces increased shoulder internal rotation velocity and elbow varus torque, these exercises may be beneficial but may also be stressful and risky. Flat-ground holds with heavy balls should not be viewed as enhancing pitching biomechanics, but rather as hybrid exercises between throwing and resistance training.

How Magnus Bends the Flying Ball--Experimenting and Modeling

ERIC Educational Resources Information Center

Timková, V.; Ješková, Z.

2017-01-01

Students are well aware of the effect of the deflection of sports balls when they have been given a spin. A volleyball, tennis, or table tennis ball served with topspin results in an additional downward force that makes the ball difficult to catch and return. In soccer, the effect of sidespin causes the ball to curve unexpectedly sideways,…

Enhancing the Bounce of a Ball

ERIC Educational Resources Information Center

Cross, Rod

2010-01-01

In sports such as baseball, softball, golf, and tennis, a common objective is to hit the ball as fast or as far as possible. Another common objective is to hit the ball so that it spins as fast as possible, since the trajectory of the ball through the air is strongly affected by ball spin. In an attempt to enhance both the coefficient of…

Determination of Contact Time of Rubber Balls Using a Digital Oscilloscope

ERIC Educational Resources Information Center

Wadhwa, Ajay

2010-01-01

We present a new method for determining the contact time of a rubber ball with the rebounding surface by using a sound-detecting electronic circuit and a digital storage oscilloscope. The rubber ball (a tennis ball or squash ball) is dropped from a known height onto a rigid surface and its contact time on first bounce is determined on the…

Propagation of self-localized Q -ball solitons in the 3He universe

NASA Astrophysics Data System (ADS)

Autti, S.; Heikkinen, P. J.; Volovik, G. E.; Zavjalov, V. V.; Eltsov, V. B.

2018-01-01

In relativistic quantum field theories, compact objects of interacting bosons can become stable owing to conservation of an additive quantum number Q . Discovering such Q balls propagating in the universe would confirm supersymmetric extensions of the standard model and may shed light on the mysteries of dark matter, but no unambiguous experimental evidence exists. We have created long-lived Q -ball solitons in superfluid 3He, where the role of the Q ball is played by a Bose-Einstein condensate of magnon quasiparticles. The principal qualitative attribute of a Q ball is observed experimentally: its propagation in space together with the self-created potential trap. Additionally, we show that this system allows for a quantitatively accurate representation of the Q -ball Hamiltonian. Our Q ball belongs to the class of the Friedberg-Lee-Sirlin Q balls with an additional neutral field ζ , which is provided by the orbital part of the Nambu-Goldstone mode. Multiple Q balls can be created in the experiment, and we have observed collisions between them. This set of features makes the magnon condensates in superfluid 3He a versatile platform for studies of Q -ball dynamics and interactions in three spatial dimensions.

Geochemistry of autochthonous and hypautochthonous siderite-dolomite coal-balls (Foord Seam, Bolsovian, Upper Carboniferous), Nova Scotia, Canada

USGS Publications Warehouse

Zodrow, E.L.; Lyons, P.C.; Millay, M.A.

1996-01-01

The 11-13 m thick Foord Seam in the fault-bounded Stellarton Basin, Nova Scotia, is the thickest seam from the Euramerican floral province known to contain coal-balls. In addition to the first discovery of autochthonous coal-balls in the Foord Seam, Nova Scotia, its shale parting also contains hypautochthonous coal-balls with histologically preserved plant structures. The coal-ball discovery helps fill a stratigraphic gap in coal-ball occurrences in the upper Carboniferous (Bolsovian) of Euramerica. The autochthonous and hypautochthonous coal-balls have a similar mineralogical composition and are composed of siderite (81-100%), dolomite-ankerite (0-19%), minor quartz and illite, and trace amounts of 'calcite'. Similar is also their permineralizing mineralogy, which consists of dolomite-ankerite and siderite. Their low pyrite content and carbonate mineralogy, and nonmarine origin, differentiates the Foord Seam coal-balls from other Euramerican coal-ball occurrences. A preliminary geochemical model, which is based on oxygen and carbon isotopic data, indicates that siderite in both the autochthonous and hypautochthonous coal-balls is of very early diagenetic (nonmarine) origin from 13C-enriched bicarbonate derived from bacterial methanogenesis of organic matter.

A Highly Miniaturized, Wireless Inertial Measurement Unit for Characterizing the Dynamics of Pitched Baseballs and Softballs

PubMed Central

McGinnis, Ryan S.; Perkins, Noel C.

2012-01-01

Baseball and softball pitch types are distinguished by the path and speed of the ball which, in turn, are determined by the angular velocity of the ball and the velocity of the ball center at the instant of release from the pitcher's hand. While radar guns and video-based motion capture (mocap) resolve ball speed, they provide little information about how the angular velocity of the ball and the velocity of the ball center develop and change during the throwing motion. Moreover, mocap requires measurements in a controlled lab environment and by a skilled technician. This study addresses these shortcomings by introducing a highly miniaturized, wireless inertial measurement unit (IMU) that is embedded in both baseballs and softballs. The resulting “ball-embedded” sensor resolves ball dynamics right on the field of play. Experimental results from ten pitches, five thrown by one softball pitcher and five by one baseball pitcher, demonstrate that this sensor technology can deduce the magnitude and direction of the ball's velocity at release to within 4.6% of measurements made using standard mocap. Moreover, the IMU directly measures the angular velocity of the ball, which further enables the analysis of different pitch types.

Study of the dynamic properties and effects of temperature using a spring model for the bouncing ball

NASA Astrophysics Data System (ADS)

Wadhwa, Ajay

2013-05-01

We studied the motion of a bouncing ball by representing it through an equivalent mass-spring system executing damped harmonic oscillations. We represented the elasticity of the system through the spring constant ‘k’ and the viscous damping effect, causing loss of energy, through damping constant ‘c’. By including these two factors we formed a differential equation for the equivalent mass-spring system of the bouncing ball. This equation was then solved to study the elastic and dynamic properties of its motion by expressing them in terms of experimentally measurable physical quantities such as contact time, coefficient of restitution, etc. We used our analysis for different types of ball material: rubber (lawn-tennis ball, super ball, soccer ball and squash ball) and plastic (table-tennis ball) at room temperature. Since the effect of temperature on the bounce of a squash ball is significant, we studied the temperature dependence of its elastic properties. The experiments were performed using audio and surface-temperature sensors interfaced with a computer through a USB port. The work presented here is suitable for undergraduate laboratories. It particularly emphasizes the use of computer interfacing for conducting conventional physics experiments.

Telescoping magnetic ball bar test gage

DOEpatents

Bryan, J.B.

1982-03-15

A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengagable servo drives which cannot be clutched out. Two gage balls are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit and a rigid member. One gage ball is secured by a magnetic socket knuckle assembly which fixes its center with respect to the machine being tested. The other gage ball is secured by another magnetic socket knuckle assembly which is engaged or held by the machine in such manner that the center of that ball is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball. As the moving ball executes its trajectory, changes in the radial distance between the centers of the two balls caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly actuated by the parallel reed flexure unit. Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball locations, thereby determining the accuracy of the machine.

Study of microforging of metallic nanoflakes in relation to electronic applications

NASA Astrophysics Data System (ADS)

Kang, Wooseung

This dissertation reports the first systematic study of cold microforging; the conversion of micron scale metal powders to thin flakes by a series of plastically deforming impacts in a ball mill at low temperature. The research focused on processing Fe and Cu flakes with submicron thicknesses (nanoflakes) which are expected to find significant applications in electronics. The principal objectives were to develop a detailed understanding of the underlying materials science of the process, and to characterize the material and processing parameters that maximize the rate at which nanoflakes with a specific aspect ratio (diameter/thickness) can be microforged. A model for microforging was developed using Hertzian impact theory to establish the compressive impact energy (Emf) imparted to a spherical powder particle in a ball-powder-ball impact, and the Coffin-Manson relation for cyclical fatigue to determine the number of plastically deforming impacts it could sustain before fracturing. The rate of microforging in the ball mill was obtained from the product of the impact frequency (f) and the statistical probability of impact (p). Both f and p depend on the number of balls and powders, and the collision velocity (v) and the milling vial volume (V). The parameters Emf, p, v and V are specific to the mill and used to develop scaling laws for transferring the process from small vibratory research mills to large commercial equipment. The empirical parameters required by these models were determined by microforging a few grams of powders in small research mills. The validity of the model was assessed by comparing the time required to microforge several hundred grams of a particular powder in a much larger mill, with that determined by scaling the model equations to account for change in mill parameters. The good agreement obtained provided strong support for the microforging model. SEM microphotos and sieving fractions were used to show that the minimum thicknesses, and maximum aspect ratios of the Fe and Cu nanoflakes that could be produced before fracture, are in the ~0.3 μm-0.5 μm range, and agreed well with those calculated from volume conserving sphere-flake transformations. X-ray diffraction measurements showed that the grain sizes of these powders were ~0.1x their thicknesses, and were little changed by microforging. The magnetic hysteresis and permeabilities of the Fe nanoflakes were in good agreement with those computed from the nanoflake geometries. The results indicate that the model of microforging as a statistical random sequence of plastic deformations can be used to develop a commercial process to support the development of their application potential in electronics.

The effect of load uncertainty on anticipatory muscle activity in catching.

PubMed

Eckerle, Jason J; Berg, William P; Ward, Rose Marie

2012-08-01

To investigate how the CNS copes with load uncertainty in catching, anticipatory postural adjustments (APAs) in one-handed catching of balls of known and unknown weights were compared. Twenty-nine (n = 29) men (mean age = 21.1 years) participated, all of whom had engaged in a sport activity requiring hand-eye coordination. Participants' muscle activity in the biceps brachii, triceps brachii, wrist flexor group, and bilateral erector spinae at L4-5 was recorded using electromyography (EMG) while they caught visually identical balls of four different weights (0.5, 1.33, 2.17, and 3.0 kg). EMG integrals were computed for the 1 s prior to ball drop (pre-drop period), and the interval between ball drop and catch (drop period). Uncertainty about ball weight had no effect on APA activity during the pre-drop period. During the drop period, however, load uncertainty did influence APA activity in the biceps brachii, triceps brachii, and the wrist flexor muscles (i.e., the effect of ball weight on APA magnitude depended on the presence or absence of load knowledge). In the known ball weight condition, participants exhibit greater APA magnitude with increases in ball weight. In contrast, under the unknown ball weight condition, APA magnitude was relatively consistent across ball weights and at a level similar to the APA magnitude for an intermediate weight (i.e., the second heaviest ball of four) in the known weight condition. In catching balls of unknown weights, the CNS appears to scale APA magnitude to afford the greatest chance of catching the ball, regardless of the weight.

Detection of microRNAs in color space.

PubMed

Marco, Antonio; Griffiths-Jones, Sam

2012-02-01

Deep sequencing provides inexpensive opportunities to characterize the transcriptional diversity of known genomes. The AB SOLiD technology generates millions of short sequencing reads in color-space; that is, the raw data is a sequence of colors, where each color represents 2 nt and each nucleotide is represented by two consecutive colors. This strategy is purported to have several advantages, including increased ability to distinguish sequencing errors from polymorphisms. Several programs have been developed to map short reads to genomes in color space. However, a number of previously unexplored technical issues arise when using SOLiD technology to characterize microRNAs. Here we explore these technical difficulties. First, since the sequenced reads are longer than the biological sequences, every read is expected to contain linker fragments. The color-calling error rate increases toward the 3(') end of the read such that recognizing the linker sequence for removal becomes problematic. Second, mapping in color space may lead to the loss of the first nucleotide of each read. We propose a sequential trimming and mapping approach to map small RNAs. Using our strategy, we reanalyze three published insect small RNA deep sequencing datasets and characterize 22 new microRNAs. A bash shell script to perform the sequential trimming and mapping procedure, called SeqTrimMap, is available at: http://www.mirbase.org/tools/seqtrimmap/ antonio.marco@manchester.ac.uk Supplementary data are available at Bioinformatics online.

Impact of Increased Football Field Width on Player High-Speed Collision Rate.

PubMed

Joseph, Jacob R; Khalsa, Siri S; Smith, Brandon W; Park, Paul

2017-07-01

High-acceleration head impact is a known risk for mild traumatic brain injury (mTBI) based on studies using helmet accelerometry. In football, offensive and defensive players are at higher risk of mTBI due to increased speed of play. Other collision sport studies suggest that increased playing surface size may contribute to reductions in high-speed collisions. We hypothesized that wider football fields lead to a decreased rate of high-speed collisions. Computer football game simulation was developed using MATLAB. Four wide receivers were matched against 7 defensive players. Each offensive player was randomized to one of 5 typical routes on each play. The ball was thrown 3 seconds into play; ball flight time was 2 seconds. Defensive players were delayed 0.5 second before reacting to ball release. A high-speed collision was defined as the receiver converging with a defensive player within 0.5 second of catching the ball. The simulation counted high-speed collisions for 1 team/season (65 plays/game for 16 games/season = 1040 plays/season) averaged during 10 seasons, and was validated against existing data using standard field width (53.3 yards). Field width was increased in 1-yard intervals up to 58.3 yards. Using standard field width, 188 ± 4 high-speed collisions were seen per team per season (18% of plays). When field width increased by 3 yards, high-speed collision rate decreased to 135 ± 3 per team per season (28% decrease; P < 0.0001). Even small increases in football field width can lead to substantial decline in high-speed collisions, with potential for reducing instances of mTBI in football players. Copyright © 2017 Elsevier Inc. All rights reserved.

[Dynamic vision of sportsmen with different requirement profiles for the visual apparatus].

PubMed

Lüder, A; Andexer, V; Witte, K; Böckelmann, I

2011-12-01

In particular, in the quick ball and racket games a good dynamic seeing is required . The afferent dynamic seeing occurs via the retiina which mediates the stimuli for efferent dynamic seeing . The aim of this study was to examine the dynamic visual acuity of sportsmen from sports with different demands on their dynamic seeing (DS). 19 sports students took part in the study. 10 subjects participated in coached team sports (group I) and 9 remaining performed individual sports (group II). The DS was assessed by means of the Düsseldorfer test for dynamic seeing of Wist which was performed twice on one day. The DS of the two groups in the first study did not differ (right eye 95.7 ± 10.6 % in group I vs. 94.3 ± 6.9 % in group II and left eye 97.6 ± 4.8 % vs. 95.3 ± 5.6 %; p ≥ 0.05). Also the second study there was no different in DS for the two groups (right eye 98.3 ± 2.6 % vs. 93.8 ± 8.0 % and left eye 99.3 ± 1.2 % vs. 95.6 ± 7.0 %; p ≥ 0.05). Our hypothesis about a different DS in players of ball games compared with non-ball sport players could not be proved. It is to be critically noted that a generalization is not possible due to the small sample numbers. Because DS is a necessary precondition in ball games further studies should be concentrated on its trainability. © Georg Thieme Verlag KG Stuttgart · New York.

Alternative actions on the K stack problem

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

Spencer, H.G.

1958-09-29

On June 6, 1958, KW Operations had HCR Channel No. 16 borescoped to determine why this rod could not be inserted on May 3. Observations revealed 3X balls in the channel and horizontal separation between graphite blocks ranging from 1/2 inch to 2 1/4 inch. The separations were noted only in the first fifteen feet in from the outer skin and in the last five feet of the channel. As a result of these findings and past operational difficulties with certain HCR`s at both KE and KW Reactors, a program of measurements is in progress to determine the extent andmore » causes of the stack displacements. From measurements and observations so far obtained, the following conclusions may be drawn about separations at locations of consequence to the loss of 3X balls from channels: Side to side horizontal separations totaling two to three inches have been observed at both reactors. The significant separations lie outside of the VSR pattern and in the lower half of the stack. The VSR pattern does not include the six outer ball 3X channels. There are probably a few small separations (< 1/2 inch) at the outer VSR`s. There are probably no separations large enough to admit balls on inner VSR channels, i.e. VSR`s inside the outer front to rear rows of VSR`s. These conclusions can not be considered fully reliable, but no information obtained to date refutes them. A team was established on 9-17-58 to evaluate and provide information on alternate courses of action for elimination or alleviation of the problem. This report contains the information and recommendations developed by the team.« less

Investigations of suprathreshold color-difference tolerances with different visual scales and different perceptual correlates using CRT colors.

PubMed

Wang, Zhehong; Xu, Haisong

2008-12-01

In order to investigate the performance of suprathreshold color-difference tolerances with different visual scales and different perceptual correlates, a psychophysical experiment was carried out by the method of constant stimuli using CRT colors. Five hue circles at three lightness (L*=30, 50, and 70) and chroma (C*ab=10, 20, and 30) levels were selected to ensure that the color-difference tolerances did not exceed the color gamut of the CRT display. Twelve color centers distributed evenly every 30 degrees along each hue circle were assessed by a panel of eight observers, and the corresponding color-difference tolerances were obtained. The hue circle with L*=50 and C*ab=20 was assessed with three different visual scales (DeltaV=3.06, 5.92, and 8.87 CIELAB units), which ranged from small to large visual scales, while the remaining hue circles were observed only with the small visual scale. The lightness tolerances had no significant correlation with the hue angles, while chroma and hue tolerances showed considerable hue angle dependences. The color-difference tolerances were linearly proportional to the visual scales but with different slopes. The lightness tolerances with different lightness levels but the same chroma showed the crispening effect to some extent, while the chroma and hue tolerances decreased with the increment of the lightness. For the color-difference tolerances with different chroma levels but the same lightness, there was no correlation between the lightness tolerances and the chroma levels, while the chroma and hue tolerances were nearly linearly proportional to the chroma levels.

Direct push driven in situ color logging tool (CLT): technique, analysis routines, and application

NASA Astrophysics Data System (ADS)

Werban, U.; Hausmann, J.; Dietrich, P.; Vienken, T.

2014-12-01

Direct push technologies have recently seen a broad development providing several tools for in situ parameterization of unconsolidated sediments. One of these techniques is the measurement of soil colors - a proxy information that reveals to soil/sediment properties. We introduce the direct push driven color logging tool (CLT) for real-time and depth-resolved investigation of soil colors within the visible spectrum. Until now, no routines exist on how to handle high-resolved (mm-scale) soil color data. To develop such a routine, we transform raw data (CIEXYZ) into soil color surrogates of selected color spaces (CIExyY, CIEL*a*b*, CIEL*c*h*, sRGB) and denoise small-scale natural variability by Haar and Daublet4 wavelet transformation, gathering interpretable color logs over depth. However, interpreting color log data as a single application remains challenging. Additional information, such as site-specific knowledge of the geological setting, is required to correlate soil color data to specific layers properties. Hence, we exemplary provide results from a joint interpretation of in situ-obtained soil color data and 'state-of-the-art' direct push based profiling tool data and discuss the benefit of additional data. The developed routine is capable of transferring the provided information obtained as colorimetric data into interpretable color surrogates. Soil color data proved to correlate with small-scale lithological/chemical changes (e.g., grain size, oxidative and reductive conditions), especially when combined with additional direct push vertical high resolution data (e.g., cone penetration testing and soil sampling). Thus, the technique allows enhanced profiling by means of providing another reproducible high-resolution parameter for analysis subsurface conditions. This opens potential new areas of application and new outputs for such data in site investigation. It is our intention to improve color measurements by means method of application and data interpretation, useful to characterize vadose layer/soil/sediment characteristics.

Aerodynamics in the classroom and at the ball park

NASA Astrophysics Data System (ADS)

Cross, Rod

2012-04-01

Experiments suitable for classroom projects or demonstrations are described concerning the aerodynamics of polystyrene balls. A light ball with sufficient backspin can curve vertically upward through the air, defying gravity and providing a dramatic visual demonstration of the Magnus effect. A ball projected with backspin can also curve downward with a vertical acceleration greater than that due to gravity if the Magnus force is negative. These effects were investigated by filming the flight of balls projected in an approximately horizontal direction so that the lift and drag forces could be easily measured. The balls were also fitted with artificial raised seams and projected with backspin toward a vertical target in order to measure the sideways deflection over a known horizontal distance. It was found that (a) a ball with a seam on one side can deflect either left or right depending on its launch speed and (b) a ball with a baseball seam can also deflect sideways even when there is no sideways component of the drag or lift forces acting on the ball. Depending on the orientations of the seam and the spin axis, a sideways force on a baseball can arise either if there is rough patch on one side of the ball or if there is a smooth patch. A scuff ball with a rough patch on one side is illegal in baseball. The effect of a smooth patch is a surprising new observation.

The strange flight behaviour of slowly spinning soccer balls

NASA Astrophysics Data System (ADS)

Mizota, Taketo; Kurogi, Kouhei; Ohya, Yuji; Okajima, Atsushi; Naruo, Takeshi; Kawamura, Yoshiyuki

2013-05-01

The strange three-dimensional flight behaviour of slowly spinning soccer balls is one of the most interesting and unknown phenomenon associated with the trajectories of sports balls. Many spectators have experienced numerous exciting and emotional instances while observing the curious flight behaviour of these balls. We examine the aerodynamic mechanisms of erratic ball behaviours through real flight observations, unsteady force measurements and flow pattern visualisations. The strange behaviour is elucidated by the relationship between the unsteady forces on the ball and the wake flow. The irregular changes in position for twin longitudinal vortices have already been discovered in the supercritical Reynolds number region of a sphere with a smooth surface. This finding is applicable to the strange behaviour of the flight of soccer balls with this supercritical flow. The players, spectators, and television viewers will gain greater insight into the effects of soccer ball flights.

Ball mounting fixture for a roundness gage

DOEpatents

Gauler, A.L.; Pasieka, D.F.

1983-11-15

A ball mounting fixture for a roundness gage is disclosed. The fixture includes a pair of chuck assemblies oriented substantially transversely with respect to one another and mounted on a common base. Each chuck assembly preferably includes a rotary stage and a wobble plate affixed thereto. A ball chuck affixed to each wobble plate is operable to selectively support a ball to be measured for roundness, with the wobble plate permitting the ball chuck to be tilted to center the ball on the axis of rotation of the rotary stage. In a preferred embodiment, each chuck assembly includes a vacuum chuck operable to selectively support the ball to be measured for roundness. The mounting fixture enables a series of roundness measurements to be taken with a conventional rotating gagehead roundness instrument, which measurements can be utilized to determine the sphericity of the ball. 6 figs.

Examining action effects in the execution of a skilled soccer kick by using erroneous feedback.

PubMed

Ford, Paul; Hodges, Nicola J; Williams, A Mark

2007-11-01

The authors examined the role of action effects (i.e., ball trajectory) during the performance of a soccer kick. Participants were 20 expert players who kicked a ball over a height barrier toward a ground-level target. The authors occluded participants' vision of the ball trajectory after foot-to-ball contact. Participants in a 1st group received erroneous feedback from a video that showed a ball-trajectory apex approximately 75 cm lower than that of their actual kick, although the ball's landing position was unaltered. Participants in a 2nd group received correct video feedback of both the ball trajectory and the landing position. The erroneous-feedback group showed a significant bias toward higher ball trajectories than did the correct-feedback group. The authors conclude that performers at high levels of skill use the visual consequences of the action to plan and execute an action.

Color-Word Stroop test performance across the adult life span.

PubMed

Uttl, B; Graf, P

1997-06-01

In the Color-Word Stroop test (CWST), the basic task is to name the ink color of rows of XXXs, and performance in this condition is compared with performance in naming the ink-color of color words under conditions where word meanings and ink colors mismatch or are incongruent (e.g., the word red printed in green ink). The present study investigated whether Stroop test interference, defined as the cost associated with ink-color naming in the incongruous stimulus condition versus in the basic color-naming condition, provides positive evidence for a kind of processing qualitatively different than that which is required for color naming or for word reading. Does the pattern of age-related differences in Stroop interference force the conclusion that the incongruous condition taps a qualitatively different kind of processing than that required for color naming or for word reading? We gave the CWST to 310 healthy adults. Their performance in each condition of the test replicates and extends previous findings. Structural equation modeling of the data showed a significant, direct link between age and performance in the latent factor associated with the incongruent condition. However, this direct link with age produced a relatively small increase in the model's fit; it amounted to only a .024 increase in the proportion of variance explained in the incongruent condition. In light of this small direct influence due to age, the most parsimonious explanation of our findings is that age effects in Stroop interference are due to age-related slowing (which is also indexed by color naming and by word reading) primarily; the findings do not provide evidence for a qualitatively different kind of processing that declines with age.

Additive benefits of autonomy support and enhanced expectancies for motor learning.

PubMed

Wulf, Gabriele; Chiviacowsky, Suzete; Cardozo, Priscila Lopes

2014-10-01

Two factors that have been shown to facilitate motor learning are autonomy support (AS) and enhanced expectancies (EE) for performance. We examined the individual and combined influences of these factors. In a 2 × 2 design, participants learning a novel motor skill (throwing with the non-dominant arm) were or were not provided a choice (AS) about the ball color on each of 6 10-trial blocks during practice, and were or were not given bogus positive social-comparative feedback (EE). This resulted in four groups: AS/EE, AS, EE, and C (control). One day after the practice phase, participants completed 10 retention and 10 transfer trials. The distance to the target--a bull's eye with a 1m radius and 10 concentric circles--was 7.5m during practice and retention, and 8.5m during transfer. Autonomy support and enhanced expectancies had additive advantages for learning, with both main effects being significant for retention and transfer. On both tests, the AS/EE group showed the greatest throwing accuracy. Also, the accuracy scores of the AS and EE groups were higher than those of the C group. Furthermore, self-efficacy measured after practice and before retention and transfer was increased by both AS and EE. Thus, supporting learners' need for autonomy by given them a small choice--even though it was not directly related to task performance--and enhancing their performance expectancies appeared to independently influence learning. Copyright © 2014 Elsevier B.V. All rights reserved.

DNA Re-EvolutioN: a game for learning molecular genetics and evolution.

PubMed

Miralles, Laura; Moran, Paloma; Dopico, Eduardo; Garcia-Vazquez, Eva

2013-01-01

Evolution is a main concept in biology, but not many students understand how it works. In this article we introduce the game DNA Re-EvolutioN as an active learning tool that uses genetic concepts (DNA structure, transcription and translation, mutations, natural selection, etc.) as playing rules. Students will learn about molecular evolution while playing a game that mixes up theory and entertainment. The game can be easily adapted to different educational levels. The main goal of this play is to arrive at the end of the game with the longest protein. Students play with pawns and dices, a board containing hypothetical events (mutations, selection) that happen to molecules, "Evolution cards" with indications for DNA mutations, prototypes of a DNA and a mRNA chain with colored "nucleotides" (plasticine balls), and small pieces simulating t-RNA with aminoacids that will serve to construct a "protein" based on the DNA chain. Students will understand how changes in DNA affect the final protein product and may be subjected to positive or negative selection, using a didactic tool funnier than classical theory lectures and easier than molecular laboratory experiments: a flexible and feasible game to learn and enjoy molecular evolution at no-cost. The game was tested by majors and non-majors in genetics from 13 different countries and evaluated with pre- and post-tests obtaining very positive results. © 2013 by The International Union of Biochemistry and Molecular Biology.

Carbon nanotube balls and their application in supercapacitors.

PubMed

Kang, Da-Young; Moon, Jun Hyuk

2014-01-08

We have provided a design of the macroscopic morphology of carbon nanotubes (CNTs) using emulsion droplet confinement. The evaporation of CNT-dispersed aqueous emulsion droplets in oil produces spherical CNT assemblies, i.e., CNT balls. In this emulsion-assisted method, compact packing of CNT was obtained by the presence of capillary pressure during droplet evaporation. The size of the CNT balls could be controlled by changing the concentration of the CNT dispersion solution; typically, CNT balls with an average size in the range of 8-12 μm were obtained with a Brunauer-Emmett-Teller (BET) specific area of 200 m(2)/g. Heat treatment of the CNT balls, which was required to remove residual solvent, and cement CNTs was followed, and their effect has been characterized; the heat treatment at high temperature desorbed surface oxygenated groups of CNTs and created defective carbon structures, but did not change pore structure. The dispersion of CNT balls was applied to form CNT ball-assembled film for a supercapacitor electrode. The specific capacitance of 80 F/g was obtained at 500 °C heat treatment, but the CNT balls prepared at a higher temperature actually decreased the capacitance, because of the removal of surface oxygenated groups, thereby decreasing the pseudo-capacitance. The capacitive properties of CNT ball-assembled electrodes were compared to CNT films; the CNT ball electrodes showed 40% higher specific electrochemical capacitance and higher rate performance, which is attributed to the compact packing of CNTs in the CNT ball and the hierarchical porous structures in the ball assemblies.

Unified picture of Q-balls and boson stars via catastrophe theory

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

Tamaki, Takashi; Sakai, Nobuyuki; Department of Education, Yamagata University, Yamagata 990-8560

2010-06-15

We make an analysis of Q-balls and boson stars using catastrophe theory, as an extension of the previous work on Q-balls in flat spacetime. We adopt the potential V{sub 3}({phi})=(m{sup 2}/2){phi}{sup 2}-{mu}{phi}{sup 3}+{lambda}{phi}{sup 4} for Q-balls and that with {mu}=0 for boson stars. For solutions with |g{sup rr}-1|{approx}1 at its peak, stability of Q-balls has been lost regardless of the potential parameters. As a result, phase relations, such as a Q-ball charge versus a total Hamiltonian energy, approach those of boson stars, which gives us a unified picture of Q-balls and boson stars.

Ball feeder for replenishing evaporator feed

DOEpatents

Felde, David K.; McKoon, Robert H.

1993-01-01

Vapor source material such as uranium, which is to be dropped into a melt in an evaporator, is made into many balls of identical diameters and placed inside a container. An elongated sloping pipe is connected to the container and leads to the evaporator such that these balls can travel sequentially therealong by gravity. A metering valve in this pipe for passing these balls one at a time is opened in response to a signal when it is ascertained by a detector that there is a ball ready to be passed. A gate in the pipe near the evaporator momentarily stops the motion of the traveling ball and is then opened to allow the ball drop into the melt at a reduced speed.

Ball feeder for replenishing evaporator feed

DOEpatents

Felde, D.K.; McKoon, R.H.

1993-03-23

Vapor source material such as uranium, which is to be dropped into a melt in an evaporator, is made into many balls of identical diameters and placed inside a container. An elongated sloping pipe is connected to the container and leads to the evaporator such that these balls can travel sequentially therealong by gravity. A metering valve in this pipe for passing these balls one at a time is opened in response to a signal when it is ascertained by a detector that there is a ball ready to be passed. A gate in the pipe near the evaporator momentarily stops the motion of the traveling ball and is then opened to allow the ball drop into the melt at a reduced speed.

Children Reorient Using the Left/Right Sense of Coloured Landmarks at 18-24 Months

ERIC Educational Resources Information Center

Nardini, Marko; Atkinson, Janette; Burgess, Neil

2008-01-01

In previous studies, children disoriented in small enclosures used room shape, but not wall colors, to find hidden objects. Their reorientation was said to depend solely on a "geometric module" informationally encapsulated with respect to color. We argue that previous studies did not fully evaluate children's use of color owing to a bias in the…

An improved quantum watermarking scheme using small-scale quantum circuits and color scrambling

NASA Astrophysics Data System (ADS)

Li, Panchi; Zhao, Ya; Xiao, Hong; Cao, Maojun

2017-05-01

In order to solve the problem of embedding the watermark into the quantum color image, in this paper, an improved scheme of using small-scale quantum circuits and color scrambling is proposed. Both color carrier image and color watermark image are represented using novel enhanced quantum representation. The image sizes for carrier and watermark are assumed to be 2^{n+1}× 2^{n+2} and 2n× 2n, respectively. At first, the color of pixels in watermark image is scrambled using the controlled rotation gates, and then, the scrambled watermark with 2^n× 2^n image size and 24-qubit gray scale is expanded to an image with 2^{n+1}× 2^{n+2} image size and 3-qubit gray scale. Finally, the expanded watermark image is embedded into the carrier image by the controlled-NOT gates. The extraction of watermark is the reverse process of embedding it into carrier image, which is achieved by applying operations in the reverse order. Simulation-based experimental results show that the proposed scheme is superior to other similar algorithms in terms of three items, visual quality, scrambling effect of watermark image, and noise resistibility.

Semi-inclusive deep inelastic scattering at small- x

NASA Astrophysics Data System (ADS)

Marquet, Cyrille; Xiao, Bo-Wen; Yuan, Feng

2009-11-01

We study the semi-inclusive hadron production in deep inelastic scattering at small-x. A transverse-momentum-dependent factorization is found consistent with the results calculated in the small-x approaches, such as the color-dipole framework and the color glass condensate, in the appropriate kinematic region at the lowest order. The transverse-momentum-dependent quark distribution can be studied in this process as a probe for the small-x saturation physics. Especially, the ratio of quark distributions as a function of transverse momentum at different x demonstrates strong dependence on the saturation scale. The Q2 dependence of the same ratio is also studied by applying the Collins-Soper-Sterman resummation method.

76 FR 57019 - Ball Bearings and Parts Thereof From France, Germany and Italy: Final Results of Sunset Reviews...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-15

... with integral shafts, ball bearings (including radial ball bearings) and parts thereof, and housed or... thereof (inner race, outer race, cage, rollers, balls, seals, shields, etc.) outlined above with certain...

Two degree of freedom camera mount

NASA Technical Reports Server (NTRS)

Ambrose, Robert O. (Inventor)

2003-01-01

A two degree of freedom camera mount. The camera mount includes a socket, a ball, a first linkage and a second linkage. The socket includes an interior surface and an opening. The ball is positioned within an interior of the socket. The ball includes a coupling point for rotating the ball relative to the socket and an aperture for mounting a camera. The first and second linkages are rotatably connected to the socket and slidably connected to the coupling point of the ball. Rotation of the linkages with respect to the socket causes the ball to rotate with respect to the socket.

Influence of the cage on friction torque in low loaded thrust ball bearing operating in dry conditions

NASA Astrophysics Data System (ADS)

Olaru, D.; Balan, M. R.; Tufescu, A.

2016-08-01

The authors investigated analytically and experimentally the friction torque in a modified thrust ball bearing operating at very low axial load in dry conditions by using only three balls and a cage. The experiments were conducted by using spin-down methodology. The results evidenced the influence of the sliding friction between the cage and the balls on the total friction torque. It was concluded that at very low loads the friction between cage and balls in a thrust ball bearing has an important contribution on total friction torque.

Thermal Stability of Gun Propellants from Munition Articles That Returned from Cambodia.

DTIC Science & Technology

1998-02-01

0482 0661 0312 0472 EMZ 79- 11 MEN 80-8 DAG 86-2 MEN 88-57 DAG 89- 11 DAG 90-3 IMI91-4 7% 9 % 12% 15% 17% 18% 16% CTG.50 inch Ball LKD...5. Peltierelement, 6. diffe- rentiemeetpunt, 7. aluminium binnenblok, 8. referentievat, 9 . isolatie, 10. verwarmingsman- tel, 11 . isolatie, 12...W/TR CTG 7,62 mm NATO Ball CTG.50 inch Med RNG Ball LKD, W/TR CTG 7,62 mm NATO Ball CTG 9 mm NATO Ball CTG 7,62 mm NATO Ball CTG 7,62 mm NATO

The relationships between impact location and post-impact ball speed, bat torsion, and ball direction in cricket batting.

PubMed

Peploe, C; McErlain-Naylor, S A; Harland, A R; King, M A

2018-06-01

Three-dimensional kinematic data of bat and ball were recorded for 239 individual shots performed by twenty batsmen ranging from club to international standard. The impact location of the ball on the bat face was determined and assessed against the resultant instantaneous post-impact ball speed and measures of post-impact bat torsion and ball direction. Significant negative linear relationships were found between post-impact ball speed and the absolute distance of impact from the midline medio-laterally and sweetspot longitudinally. Significant cubic relationships were found between the distance of impact from the midline of the bat medio-laterally and both a measure of bat torsion and the post-impact ball direction. A "sweet region" on the bat face was identified whereby impacts within 2 cm of the sweetspot in the medio-lateral direction, and 4.5 cm in the longitudinal direction, caused reductions in ball speed of less than 6% from the optimal value, and deviations in ball direction of less than 10° from the intended target. This study provides a greater understanding of the margin for error afforded to batsmen, allowing researchers to assess shot success in more detail, and highlights the importance of players generating consistently central impact locations when hitting for optimal performance.

CFD Analysis of Swing of Cricket Ball and Trajectory Prediction

NASA Astrophysics Data System (ADS)

G, Jithin; Tom, Josin; Ruishikesh, Kamat; Jose, Jyothish; Kumar, Sanjay

2013-11-01

This work aims to understand the aerodynamics associated with the flight and swing of a cricket ball and predict its flight trajectory over the course of the game: at start (smooth ball) and as the game progresses (rough ball). Asymmetric airflow over the ball due to seam orientation and surface roughness can cause flight deviation (swing). The values of Drag, Lift and Side forces which are crucial for determining the trajectory of the ball were found with the help of FLUENT using the standard K- ɛ model. Analysis was done to study how the ball velocity, spin imparted to be ball and the tilt of the seam affects the movement of the ball through air. The governing force balance equations in 3 dimensions in combination a MATLAB code which used Heun's method was used for obtaining the trajectory of the ball. The conditions for the conventional swing and reverse swing to occur were deduced from the analysis and found to be in alignment with the real life situation. Critical seam angle for maximum swing and transition speed for normal to reverse swing were found out. The obtained trajectories were compared to real life hawk eye trajectories for validation. The analysis results were in good agreement with the real life situation.

Telescoping magnetic ball bar test gage

DOEpatents

Bryan, J.B.

1984-03-13

A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengageable servo drives which cannot be clutched out is disclosed. Two gage balls are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit and a rigid member. One gage ball is secured by a magnetic socket knuckle assembly which fixes its center with respect to the machine being tested. The other gage ball is secured by another magnetic socket knuckle assembly which is engaged or held by the machine in such manner that the center of that ball is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball. As the moving ball executes its trajectory, changes in the radial distance between the centers of the two balls caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly actuated by the parallel reed flexure unit. Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball locations, thereby determining the accuracy of the machine. 3 figs.

New Skeletal-Space-Filling Models

ERIC Educational Resources Information Center

Clarke, Frank H.

1977-01-01

Describes plastic, skeletal molecular models that are color-coded and can illustrate both the conformation and overall shape of small molecules. They can also be converted to space-filling counterparts by the additions of color-coded polystyrene spheres. (MLH)

The Rich Color Variations of Pluto

NASA Image and Video Library

2015-09-24

NASA's New Horizons spacecraft captured this high-resolution enhanced color view of Pluto on July 14, 2015. The image combines blue, red and infrared images taken by the Ralph/Multispectral Visual Imaging Camera (MVIC). Pluto's surface sports a remarkable range of subtle colors, enhanced in this view to a rainbow of pale blues, yellows, oranges, and deep reds. Many landforms have their own distinct colors, telling a complex geological and climatological story that scientists have only just begun to decode. The image resolves details and colors on scales as small as 0.8 miles (1.3 kilometers). http://photojournal.jpl.nasa.gov/catalog/PIA19952

Electrically actuatable temporal tristimulus-color device

DOEpatents

Koehler, Dale R.

1992-01-01

The electrically actuated light filter operates in a cyclical temporal mode to effect a tristimulus-color light analyzer. Construction is based on a Fabry-Perot interferometer comprised of a high-speed movable mirror pair and cyclically powered electrical actuators. When combined with a single vidicon tube or a monochrome solid state image sensor, a temporally operated tristimulus-color video camera is effected. A color-generated is accomplished when constructed with a companion light source and is a flicker-free colored-light source for transmission type display systems. Advantages of low cost and small physical size result from photolithographic batch-processing manufacturability.

Color-Matching and Blending-Effect of Universal Shade Bulk-Fill-Resin-Composite in Resin-Composite-Models and Natural Teeth.

PubMed

Abdelraouf, Rasha M; Habib, Nour A

2016-01-01

Objectives . To assess visually color-matching and blending-effect (BE) of a universal shade bulk-fill-resin-composite placed in resin-composite-models with different shades and cavity sizes and in natural teeth (extracted and patients' teeth). Materials and Methods . Resin-composite-discs (10 mm × 1 mm) were prepared of universal shade composite and resin-composite of shades: A1, A2, A3, A3.5, and A4. Spectrophotometric-color-measurement was performed to calculate color-difference (Δ E ) between the universal shade and shaded-resin-composites discs and determine their translucency-parameter (TP). Visual assessment was performed by seven normal-color-vision-observers to determine the color-matching between the universal shade and each shade, under Illuminant D65. Color-matching visual scoring (VS) values were expressed numerically (1-5): 1: mismatch/totally unacceptable, 2: Poor-Match/hardly acceptable, 3: Good-Match/acceptable, 4: Close-Match/small-difference, and 5: Exact-Match/no-color-difference. Occlusal cavities of different sizes were prepared in teeth-like resin-composite-models with shades A1, A2, A3, A3.5, and A4. The cavities were filled by the universal shade composite. The same scale was used to score color-matching between the fillings and composite-models. BE was calculated as difference in mean-visual-scores in models and that of discs. Extracted teeth with two different class I-cavity sizes as well as ten patients' lower posterior molars with occlusal caries were prepared, filled by universal shade composite, and assessed similarly. Results . In models, the universal shade composite showed close matching in the different cavity sizes and surrounding shades (4 ≤ VS < 5) (BE = 0.6-2.9 in small cavities and 0.5-2.8 in large cavities). In extracted teeth, there was good-to-close color-matching (VS = 3.7-4.4 in small cavities, BE = 2.5-3.2) (VS = 3-3.5, BE = 1.8-2.3 in large cavities). In patients' molars, the universal shade composite showed good-matching (VS = 3-3.3, BE = -0.9-2.1). Conclusions . Color-matching of universal shade resin-composite was satisfactory rather than perfect in patients' teeth.

Evaporation-induced self-assembly of quantum dots-based concentric rings on polymer-based nanocomposite films.

PubMed

Zhang, Shaofu; Luan, Weiling; Zhong, Qixin; Yin, Shaofeng; Yang, Fuqian

2016-10-12

The "ball-on-film" template is used to construct concentric rings on the surface of PMMA-QDs (polymethyl methacrylate - quantum dots) nanocomposite films via the evaporation of pure chloroform droplets, which are confined by a steel ball. The concentric rings consist of QDs, as revealed by the fluorescence images of the concentric rings. The photoluminescence intensity of the concentric rings increases with the increase of the distance to the ball center, suggesting that the amount of QDs accumulated around the contact line at individual stick state increases with the increase of the distance to the ball center. Both the wavelength and cross-sectional area (width) of the concentric rings increase approximately linearly with increasing distance to the ball center, independent of the ball size, the film thickness and the QDs concentration. For the PMMA-QDs nanocomposite films prepared from the same QDs concentration in chloroform, the thicker the PMMA-QDs nanocomposite film, the larger the wavelength for the same distance to the ball center. The effect of confinement of two steel balls on the surface patterns over the PMMA-QDs nanocomposite films is studied via a template of "two spheres on film". Symmetric surface patterns are formed. There exist two types of featureless zone between the two balls, depending on the distance between the two balls: one is the inner featureless zone and the other is the outer featureless zone. The size of both featureless zones increases with the increase of the ball distance.

Detonator-activated ball shutter

DOEpatents

McWilliams, Roy A.; von Holle, William G.

1983-01-01

A detonator-activated ball shutter for closing an aperture in about 300.mu. seconds. The ball shutter containing an aperture through which light, etc., passes, is closed by firing a detonator which propels a projectile for rotating the ball shutter, thereby blocking passage through the aperture.

Playing Ball in a Space Station

ERIC Educational Resources Information Center

Simoson, Andrew J.

2006-01-01

How does artificial gravity affect the path of a thrown ball? This paper contrasts ball trajectories on the Little Prince's asteroid planet B-612 and Arthur C. Clarke's rotating-drum spacecraft of 2001, and demonstrates curve balls with multiple loops in the latter environment.

Micro structrual characterization and analysis of ball milled silicon carbide

NASA Astrophysics Data System (ADS)

Madhusudan, B. M.; Raju, H. P.; Ghanaraja., S.

2018-04-01

Mechanical alloying has been one of the prominent methods of powder synthesis technique in solid state involving cyclic deformation, cold welding and fracturing of powder particles. Powder particles in this method are subjected to greater mechanical deformation due to the impact of ball-powder-ball and ball-powder-container collisions that occurs during mechanical alloying. Strain hardening and fracture of particles decreases the size of the particles and creates new surfaces. The objective of this Present work is to use ball milling of SiC powder for different duration of 5, 10, 15 and 20 hours by High energy planetary ball milling machine and to evaluate the effect of ball milling on SiC powder. Micro structural Studies using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and EDAX has been investigated.

Assessment of head injury of children due to golf ball impact.

PubMed

Lee, Heow Pueh; Wang, Fang

2010-10-01

Head trauma injury due to impact by a flying golf ball is one of the most severe possible injury accidents on the golf course. Numerical simulations based on the finite element method are presented to investigate head injury in children due to impact by a flying golf ball. The stress and energy flow patterns in a head model during the golf ball impact are computed for various combinations of striking speed, falling angle of the golf ball before impact, and impact location. It is found that a child is more prone to head injury due to golf ball impact on the frontal and side/temporal areas. The simulated results are found to conform to the clinical reports on children's head injuries from flying golf balls.

Preparation of Si nano-crystals with controlled oxidation state from SiO disproportionated by ZrO2 ball-milling

NASA Astrophysics Data System (ADS)

Okamoto, Yuji; Harada, Yoshitomo; Ohta, Narumi; Takada, Kazunori; Sumiya, Masatomo

2016-09-01

We demonstrate that a SiO disproportionation reaction can be achieved simply by high energy mechanochemical milling. The planetary ball-milling of ZrO2 for a few minutes generated Si nano-crystals. Milling conditions including rotation speed, ball number, milling time, and type of ball material were able to control the oxidation states of Si. The ball-milled SiO powder was tested as an anode of a lithium battery. ZrO2 contamination from the vial and balls was eliminated by dipping the ball-milled SiO powder in (NH4)HSO4 molten salt and heating for 5 min. The disproportionated SiO powder showed characteristics comparable to those of a powder prepared by a conventional heating process taking several hours.

Application of coordinate transform on ball plate calibration

NASA Astrophysics Data System (ADS)

Wei, Hengzheng; Wang, Weinong; Ren, Guoying; Pei, Limei

2015-02-01

For the ball plate calibration method with coordinate measurement machine (CMM) equipped with laser interferometer, it is essential to adjust the ball plate parallel to the direction of laser beam. It is very time-consuming. To solve this problem, a method based on coordinate transformation between machine system and object system is presented. With the fixed points' coordinates of the ball plate measured in the object system and machine system, the transformation matrix between the coordinate systems is calculated. The laser interferometer measurement data error due to the placement of ball plate can be corrected with this transformation matrix. Experimental results indicate that this method is consistent with the handy adjustment method. It avoids the complexity of ball plate adjustment. It also can be applied to the ball beam calibration.

Infrared small target tracking based on SOPC

NASA Astrophysics Data System (ADS)

Hu, Taotao; Fan, Xiang; Zhang, Yu-Jin; Cheng, Zheng-dong; Zhu, Bin

2011-01-01

The paper presents a low cost FPGA based solution for a real-time infrared small target tracking system. A specialized architecture is presented based on a soft RISC processor capable of running kernel based mean shift tracking algorithm. Mean shift tracking algorithm is realized in NIOS II soft-core with SOPC (System on a Programmable Chip) technology. Though mean shift algorithm is widely used for target tracking, the original mean shift algorithm can not be directly used for infrared small target tracking. As infrared small target only has intensity information, so an improved mean shift algorithm is presented in this paper. How to describe target will determine whether target can be tracked by mean shift algorithm. Because color target can be tracked well by mean shift algorithm, imitating color image expression, spatial component and temporal component are advanced to describe target, which forms pseudo-color image. In order to improve the processing speed parallel technology and pipeline technology are taken. Two RAM are taken to stored images separately by ping-pong technology. A FLASH is used to store mass temp data. The experimental results show that infrared small target is tracked stably in complicated background.

Heading in football. Part 3: Effect of ball properties on head response

PubMed Central

Shewchenko, N; Withnall, C; Keown, M; Gittens, R; Dvorak, J

2005-01-01

Objectives: Head impacts from footballs are an essential part of the game but have been implicated in mild and acute neuropsychological impairment. Ball characteristics have been noted in literature to affect the impact response of the head; however, the biomechanics are not well understood. The present study determined whether ball mass, pressure, and construction characteristics help reduce head and neck can impact response. Methods: Head responses under ball impact (6–7 m/s) were measured with a biofidelic numerical human model and controlled human subject trials (n = 3). Three ball masses and four ball pressures were investigated for frontal heading. Further, the effect of ball construction in wet/dry conditions was studied with the numerical model. The dynamic ball characteristics were determined experimentally. Head linear and angular accelerations were measured and compared with injury assessment functions comprising peak values and head impact power. Neck responses were assessed with the numerical model. Results: Ball mass reductions up to 35% resulted in decreased head responses up to 23–35% for the numerical and subject trials. Similar decreases in neck axial and shear responses were observed. Ball pressure reductions of 50% resulted in head and neck response reductions up to 10–31% for the subject trials and numerical model. Head response reductions up to 15% were observed between different ball constructions. The wet condition generally resulted in greater head and neck responses of up to 20%. Conclusion: Ball mass, pressure, and construction can reduce the impact severity to the head and neck. It is foreseeable that the benefits can be extended to players of all ages and skill levels. PMID:16046354

An investigation of the generation and properties of laboratory-produced ball lightning

NASA Astrophysics Data System (ADS)

Oreshko, A. G.

2015-06-01

The experiments revealed that ball lightning is a self-confining quasi-neutral in a whole plasma system that rotates around its axis. Ball lightning has a structure of a spherical electric domain, consisting of a kernel with excess negative charge and an external spherical layer with excess positive charge. The excess of charges of one sort and the lack of charges of the other sort in the kernel or in the external spherical layer significantly reduces the possibility of electron capture by means of an electric field, created by the nearest ions and leads to a drastic slowdown of recombination process. Direct proof has been obtained that inside of ball lightning - in an external spherical layer that rotates around the axis - there is a circular current of sub-relativistic particles. This current creates and maintains its own poloidal magnetic field of ball lightning, i.e. it carries out the function of magnetic dynamo. The kernel of ball lightning is situated in a region with minimum values of induction of the magnetic field. The inequality of positive and negative charges in elements of ball lightning also significantly reduces losses of the charged plasma on bremsstrahlung. Ball lightning generation occurs in a plasmic vortex. The ball lightning energy in the region of its generation significantly differs from the ball lightning energy, which is drifting in space. The axial component of kinetic energy of particles slightly exceeds 100 keV and the rotational component of the ions energy is a bit greater than 1 MeV. Ball lightning is `embedded' in atmosphere autonomous accelerator of charged particles of a cyclotron type due to self-generation of strong crossed electric and magnetic fields. A discussion of the conditions of stability and long-term existence of ball lightning is given.

HYDRAULIC SERVO

DOEpatents

Wiegand, D.E.

1962-05-01

A hydraulic servo is designed in which a small pressure difference produced at two orifices by an electrically operated flapper arm in a constantly flowing hydraulic loop is hydraulically amplified by two constant flow pumps, two additional orifices, and three unconnected ball pistons. Two of the pistons are of one size and operate against the additional orifices, and the third piston is of a different size and operates between and against the first two pistons. (AEC)

Assessment of Industrial Attitudes Toward Generic Research Needs in Tribology

DTIC Science & Technology

1985-09-01

Ford (3) Chrysler (4) Aerospace Pratt and Whitney ( 5 ) Williams International (6) Hughes (7) Small Mechanical Products Xerox (19) Black and...correlation of the 4-^ball with the 5 -J-car tests was interesting and valuable, but some reservations were indicated about its applicability over wider...resulting from excessive vibration. 5 . Generally interested in DOE work presented. Least interested in high temperature applications . 6. Interested in

Visualization of Kepler’s laws of planetary motion

NASA Astrophysics Data System (ADS)

Lu, Meishu; Su, Jun; Wang, Weiguo; Lu, Jianlong

2017-03-01

For this article, we use a 3D printer to print a surface similar to universal gravitation for demonstrating and investigating Kepler’s laws of planetary motion describing the motion of a small ball on the surface. This novel experimental method allows Kepler’s laws of planetary motion to be visualized and will contribute to improving the manipulative ability of middle school students and the accessibility of classroom education.

SPHERES Slosh

NASA Image and Video Library

2014-06-18

ISS040-E-013914 (18 June 2014) --- In the International Space Station's Kibo laboratory, NASA astronauts Steve Swanson (left), Expedition 40 commander; and Reid Wiseman, flight engineer, conduct test runs of the SPHERES-Slosh experiment, using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES. The SPHERES-Slosh investigation uses small robotic satellites on the space station to examine how liquids move around inside containers in microgravity.

SPHERES Slosh

NASA Image and Video Library

2014-06-18

ISS040-E-014615 (18 June 2014) --- In the International Space Station's Kibo laboratory, NASA astronauts Steve Swanson (top), Expedition 40 commander; and Reid Wiseman, flight engineer, conduct test runs of the SPHERES-Slosh experiment, using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES. The SPHERES-Slosh investigation uses small robotic satellites on the space station to examine how liquids move around inside containers in microgravity.

SPHERES Slosh

NASA Image and Video Library

2014-06-18

ISS040-E-014147 (18 June 2014) --- In the International Space Station's Kibo laboratory, NASA astronauts Steve Swanson (foreground), Expedition 40 commander; and Reid Wiseman, flight engineer, conduct test runs of the SPHERES-Slosh experiment, using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES. The SPHERES-Slosh investigation uses small robotic satellites on the space station to examine how liquids move around inside containers in microgravity.

SPHERES Slosh

NASA Image and Video Library

2014-06-18

ISS040-E-014536 (18 June 2014) --- In the International Space Station's Kibo laboratory, NASA astronauts Steve Swanson (left), Expedition 40 commander; and Reid Wiseman, flight engineer, conduct test runs of the SPHERES-Slosh experiment, using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES. The SPHERES-Slosh investigation uses small robotic satellites on the space station to examine how liquids move around inside containers in microgravity.

SPHERES Slosh

NASA Image and Video Library

2014-06-18

ISS040-E-014444 (18 June 2014) --- In the International Space Station's Kibo laboratory, NASA astronauts Steve Swanson (left), Expedition 40 commander; and Reid Wiseman, flight engineer, conduct test runs of the SPHERES-Slosh experiment, using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES. The SPHERES-Slosh investigation uses small robotic satellites on the space station to examine how liquids move around inside containers in microgravity.

SPHERES Slosh

NASA Image and Video Library

2014-06-18

ISS040-E-015415 (18 June 2014) --- In the International Space Station's Kibo laboratory, NASA astronauts Steve Swanson, Expedition 40 commander; and Reid Wiseman (partially obscured), flight engineer, conduct test runs of the SPHERES-Slosh experiment, using the soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES. The SPHERES-Slosh investigation uses small robotic satellites on the space station to examine how liquids move around inside containers in microgravity.

Aluminum-Scandium: A Material for Semiconductor Packaging

NASA Astrophysics Data System (ADS)

Geissler, Ute; Thomas, Sven; Schneider-Ramelow, Martin; Mukhopadhyay, Biswajit; Lang, Klaus-Dieter

2016-10-01

A well-known aluminum-scandium (Al-Sc) alloy, already used in lightweight sports equipment, is about to be established for use in electronic packaging. One application for Al-Sc alloy is manufacture of bonding wires. The special feature of the alloy is its ability to harden by precipitation. The new bonding wires with electrical conductivity similar to pure Al wires can be processed on common wire bonders for aluminum wedge/wedge (w/w) bonding. The wires exhibit very fine-grained microstructure. Small Al3Sc particles are the main reason for its high strength and prevent recrystallization and grain growth at higher temperatures (>150°C). After the wire-bonding process, the interface is well closed. Reliability investigations by active power cycling demonstrated considerably improved lifetime compared with pure Al heavy wires. Furthermore, the Al-Sc alloy was sputter-deposited onto silicon wafer to test it as chip metallization in copper (Cu) ball/wedge bonding technology. After deposition, the layers exhibited fine-grained columnar structure and small coherent Al3Sc particles with dimensions of a few nanometers. These particles inhibit softening processes such as Al splashing in fine wire bonding processes and increase the thickness of remnant Al under the copper balls to 85% of the initial thickness.

Structure of Immune Stimulating Complex Matrices and Immune Stimulating Complexes in Suspension Determined by Small-Angle X-Ray Scattering

PubMed Central

Pedersen, Jan Skov; Oliveira, Cristiano L.P.; Hübschmann, Henriette Baun; Arleth, Lise; Manniche, Søren; Kirkby, Nicolai; Nielsen, Hanne Mørck

2012-01-01

Immune stimulating complex (ISCOM) particles consisting of a mixture of Quil-A, cholesterol, and phospholipids were structurally characterized by small-angle x-ray scattering (SAXS). The ISCOM particles are perforated vesicles of very well-defined structures. We developed and implemented a novel (to our knowledge) modeling method based on Monte Carlo simulation integrations to describe the SAXS data. This approach is similar to the traditional modeling of SAXS data, in which a structure is assumed, the scattering intensity is calculated, and structural parameters are optimized by weighted least-squares methods when the model scattering intensity is fitted to the experimental data. SAXS data from plain ISCOM matrix particles in aqueous suspension, as well as those from complete ISCOMs (i.e., with an antigen (tetanus toxoid) incorporated) can be modeled as a polydisperse distribution of perforated bilayer vesicles with icosahedral, football, or tennis ball structures. The dominating structure is the tennis ball structure, with an outer diameter of 40 nm and with 20 holes 5–6 nm in diameter. The lipid bilayer membrane is 4.6 nm thick, with a low-electron-density, 2.0-nm-thick hydrocarbon core. Surprisingly, in the ISCOMs, the tetanus toxoid is located just below the membrane inside the particles. PMID:22677391

Investigation into the mechanisms of closed three-body abrasive wear

NASA Astrophysics Data System (ADS)

Dwyer-Joyce, R. S.; Sayles, R. S.; Ioannides, E.

1994-06-01

Contacting components frequently fail by abrasion caused by solid contaminants in the lubricant. This process can be classified as a closed three-body abrasive wear process. The mechanisms by which trapped particles cause material removal are not fully understood. This paper describes tests using model elastohydrodynamic contacts to study these mechanisms. An optical elastohydrodynamic lubrication rig has been used to study the deformation and fracture of ductile and brittle lubricant-borne debris. A ball-on-disk machine was used to study the behavior of the particles in partially sliding contacts. Small diamond particles were used as abrasives since these were thought not to break down in the contact; wear could then be directly related to particles of a known size. The particles were found to embed in the softer surface and to scratch the harder. The mass of material worn from the ball surface was approximately proportional to the particle sliding distance and abrasive concentration. Small particles tumbled through the contact, while larger particles ploughed. Mass loss was found to increase with abrasive particle size. Individual abrasion scratches have been measured and related to the abrading particle. A simple model of the abrasive process has been developed and compared with experimental data. The discrepancies are thought to be the result of the uncertainty about the entrainment of particles into the contact.

Effect of milling on particle shape and surface energy heterogeneity of needle-shaped crystals.

PubMed

Ho, Raimundo; Naderi, Majid; Heng, Jerry Y Y; Williams, Daryl R; Thielmann, Frank; Bouza, Peter; Keith, Adam R; Thiele, Greg; Burnett, Daniel J

2012-10-01

Milling and micronization of particles are routinely employed in the pharmaceutical industry to obtain small particles with desired particle size characteristics. The aim of this study is to demonstrate that particle shape is an important factor affecting the fracture mechanism in milling. Needle-shaped crystals of the β polymorph of D-mannitol were prepared from recrystallization in water. A portion of the recrystallized materials was ball-milled. Unmilled and milled sieved fractions of recrystallized D-mannitol were analyzed by dynamic image analysis (DIA) and inverse gas chromatography (IGC) at finite concentration to explain the breakage/fracture behavior. In the process of ball-milling, D-mannitol preferentially fractured along their shortest axis, exposing (011) plane with increased hydrophilicity and increased bounding rectangular aspect ratio. This is in contrary to attachment energy modeling which predicts a fracture mechanism across the (010) plane with increased hydrophobicity, and small change in particle shape. Crystal size, and more importantly, crystal shape and facet-specific mechanical properties, can dictate the fracture/cleavage behavior of organic crystalline materials. Thorough understanding of the crystal slip systems, combining attachment energy prediction with particle shape and surface characterization using DIA and IGC, are important in understanding fracture behavior of organic crystalline solids in milling and micronization.

Classification of event location using matched filters via on-floor accelerometers

NASA Astrophysics Data System (ADS)

Woolard, Americo G.; Malladi, V. V. N. Sriram; Alajlouni, Sa'ed; Tarazaga, Pablo A.

2017-04-01

Recent years have shown prolific advancements in smart infrastructures, allowing buildings of the modern world to interact with their occupants. One of the sought-after attributes of smart buildings is the ability to provide unobtrusive, indoor localization of occupants. The ability to locate occupants indoors can provide a broad range of benefits in areas such as security, emergency response, and resource management. Recent research has shown promising results in occupant building localization, although there is still significant room for improvement. This study presents a passive, small-scale localization system using accelerometers placed around the edges of a small area in an active building environment. The area is discretized into a grid of small squares, and vibration measurements are processed using a pattern matching approach that estimates the location of the source. Vibration measurements are produced with ball-drops, hammer-strikes, and footsteps as the sources of the floor excitation. The developed approach uses matched filters based on a reference data set, and the location is classified using a nearest-neighbor search. This approach detects the appropriate location of impact-like sources i.e. the ball-drops and hammer-strikes with a 100% accuracy. However, this accuracy reduces to 56% for footsteps, with the average localization results being within 0.6 m (α = 0.05) from the true source location. While requiring a reference data set can make this method difficult to implement on a large scale, it may be used to provide accurate localization abilities in areas where training data is readily obtainable. This exploratory work seeks to examine the feasibility of the matched filter and nearest neighbor search approach for footstep and event localization in a small, instrumented area within a multi-story building.

2012 Problem 15: Frustrating Golf Ball

NASA Astrophysics Data System (ADS)

Huang, Shan; Zhu, Zheyuan; Gao, Wenli; Wang, Sihui

2015-10-01

This paper studies the condition for a golf ball to escape from a hole. The two determining factors are the ball's initial velocity v0 and its deviation from the center of the hole d. There is a critical escaping velocity vc for every deviation d. The ball's motion is analyzed by calculating the change of velocity whenever the ball collides with the hole. The critical conditions predicted by our theory are verified through experiment.

Device Rotates Bearing Balls For Inspection

NASA Technical Reports Server (NTRS)

Burley, R. K.

1988-01-01

Entire surface of ball inspected automatically and quickly. Device holds and rotates bearing ball for inspection by optical or mechanical surface-quality probe, eddy-current probe for detection of surface or subsurface defects, or circumference-measuring tool. Ensures entire surface of ball moves past inspection head quickly. New device saves time and increases reliability of inspections of spherical surfaces. Simple to operate and provides quick and easy access for loading and unloading of balls during inspection.

Experimental evaluation of stresses in spherically hollow balls

NASA Technical Reports Server (NTRS)

Nypan, L. J.

1974-01-01

An analysis was undertaken to evaluate stresses within spherically hollow ball bearings proportioned for 40, 50, and 60% mass reductions. Strain gage rosettes were used to determine principal strains and stresses in the steel ball models statically loaded in various orientations. Dimensionless results are reported for the balls under flate plate contact loads. Similitude considerations permit these results to be applied to calculate stresses in hollow ball bearings proportioned to these mass reductions.

Detonator-activated ball shutter

DOEpatents

McWilliams, R.A.; Holle, W.G. von.

1983-08-16

A detonator-activated ball shutter for closing an aperture in about 300[mu] seconds. The ball shutter containing an aperture through which light, etc., passes, is closed by firing a detonator which propels a projectile for rotating the ball shutter, thereby blocking passage through the aperture. 3 figs.

Fatigue life of high-speed ball bearings with silicon nitride balls

NASA Technical Reports Server (NTRS)

Parker, R. J.; Zaretsky, E. V.

1974-01-01

Hot-pressed silicon nitride was evaluated as a rolling-element bearing material. The five-ball fatigue tester was used to test 12.7-mm- diameter silicon nitride balls at maximum Hertz stresses ranging from 4.27 x 10 to the 9th power n/sq m to 6.21 x 10 to the 9th power n/sq m at a race temperature of 328K. The fatigue life of NC-132 hot-pressed silicon nitride was found to be equal to typical bearing steels and much greater than other ceramic or cermet materials at the same stress levels. A digital computer program was used to predict the fatigue life of 120-mm- bore angular-contact ball bearings containing either steel or silicon nitride balls. The analysis indicates that there is no improvement in the lives of bearings of the same geometry operating at DN values from 2 to 4 million where silicon nitride balls are used in place of steel balls.

Evaluation and Description of Friction between an Electro-Deposited Coating and a Ceramic Ball under Fretting Condition

PubMed Central

Kim, Kyungmok

2015-01-01

This article describes fretting behavior of zirconia and silicon nitride balls on an electro-deposited coating. Fretting tests are performed using a ball-on-flat configuration. The evolution of the kinetic friction coefficient is determined, along with slip ratio. Experimental results show that the steady-state friction coefficient between ceramic balls (Si3N4 and ZrO2) and an electro-deposited coating is about 0.06, lower than the value between AISI 52100 ball and the coating. After a steady-state sliding, the transition of the friction coefficient is varied with a ball. The friction coefficient for ZrO2 balls became a critical value after higher fretting cycles than those for Si3N4 and AISI 52100 balls. In addition, it is identified that two parameters can describe the transition of the friction coefficient. Finally, the evolution of the friction coefficient is expressed as an exponential or a power-law form. PMID:28793471

Ball Lightning in Zero Gravity in the Laboratory

NASA Astrophysics Data System (ADS)

Alexeff, Igor; Parameswaran, Sriram; Grace, Michael

2004-11-01

We have created balls of orange plasma in atmospheric - pressure air that survive for over 1/2 second without power input. The technique used was to create a pulsed horizontal electric arc in a zero - gravity environment using 6 neon - sign transformers in parallel, each producing 16,000 V at 60 mA. The zero - gravity environment reduces heat losses by reducing thermal convection, creating a larger ball. Previous work (1) suggests that the ball lifetime scales as the square of the ball radius. The balls were photographed after power turnoff with a high - speed 16 mm movie camera. Movies of the balls being formed and decaying will be shown. We suggest that there are several other forms of ball lightning (2). 1.Igor Alexeff et. al. International Conference On Plasma Science, Jeju, Korea, June 2-5, 2003, Conference Record, p 254. 2. Igor Alexeff and Mark Rader, IEEE Transactions on Plasma Science, Vol. 20, No. 6, Dec. 1992, pp.669-671. Igor Alexeff and Mark Rader, Fusion Technology, Vol. 27, May 1995, p. 271.

"We're just targeted as the flock that has HIV": health care experiences of members of the house/ball culture.

PubMed

Rowan, Diana; DeSousa, Maysa; Randall, Ethan Makai; White, Chelsea; Holley, Lamont

2014-01-01

The house/ball community is an understudied sub-group of young Black men who have sex with men and transgender persons in urban centers of the United States who affiliate in social structures called houses and gather at elaborate dance and performance events called balls. In Charlotte, North Carolina, 12 house/ball members were interviewed about their experiences with health care providers and their assessment of any barriers to care due to their affiliation with the rather clandestine house/ball sub-culture. Additionally, HIV-specific health care providers were interviewed, to assess their knowledge of the sub-culture. House/ball members reported both positive and negative perceptions of treatment by their health care providers with respect to their house/ball involvement. Some reported feeling stigmatized, especially around HIV status. Results showed that increased knowledge about the house/ball community could improve practitioners' cultural competence, thereby reducing stigma-related barriers to care.

Hollow fiber-optic Raman probes for small experimental animals

NASA Astrophysics Data System (ADS)

Katagiri, Takashi; Hattori, Yusuke; Suzuki, Toshiaki; Matsuura, Yuji; Sato, Hidetoshi

2007-02-01

Two types of hollow fiber-optic probes are developed to measure the in vivo Raman spectra of small animals. One is the minimized probe which is end-sealed with the micro-ball lens. The measured spectra reflect the information of the sample's sub-surface. This probe is used for the measurement of the esophagus and the stomach via an endoscope. The other probe is a confocal Raman probe which consists of a single fiber and a lens system. It is integrated into the handheld microscope. A simple and small multimodal probe is realized because the hollow optical fiber requires no optical filters. The performance of each probe is examined and the effectiveness of these probes for in vivo Raman spectroscopy is shown by animal tests.

Modeling Color Difference for Visualization Design.

PubMed

Szafir, Danielle Albers

2018-01-01

Color is frequently used to encode values in visualizations. For color encodings to be effective, the mapping between colors and values must preserve important differences in the data. However, most guidelines for effective color choice in visualization are based on either color perceptions measured using large, uniform fields in optimal viewing environments or on qualitative intuitions. These limitations may cause data misinterpretation in visualizations, which frequently use small, elongated marks. Our goal is to develop quantitative metrics to help people use color more effectively in visualizations. We present a series of crowdsourced studies measuring color difference perceptions for three common mark types: points, bars, and lines. Our results indicate that peoples' abilities to perceive color differences varies significantly across mark types. Probabilistic models constructed from the resulting data can provide objective guidance for designers, allowing them to anticipate viewer perceptions in order to inform effective encoding design.

Cerebellar subjects show impaired adaptation of anticipatory EMG during catching.

PubMed

Lang, C E; Bastian, A J

1999-11-01

We evaluated the role of the cerebellum in adapting anticipatory muscle activity during a multijointed catching task. Individuals with and without cerebellar damage caught a series of balls of different weights dropped from above. In Experiment 1 (light-heavy-light), each subject was required to catch light balls (baseline phase), heavy balls (adaptation phase), and then light balls again (postadaptation phase). Subjects were not told when the balls would be switched, and they were required to keep their hand within a vertical spatial "window" during the catch. During the series of trials, we measured three-dimensional (3-D) position and electromyogram (EMG) from the catching arm. We modeled the adaptation process using an exponential decay function; this model allowed us to dissociate adaptation from performance variability. Results from the position data show that cerebellar subjects did not adapt or adapted very slowly to the changed ball weight when compared with the control subjects. The cerebellar group required an average of 30.9 +/- 8.7 trials (mean +/- SE) to progress approximately two-thirds of the way through the adaptation compared with 1.7 +/- 0.2 trials for the control group. Only control subjects showed a negative aftereffect indicating storage of the adaptation. No difference in performance variability existed between the two groups. EMG data show that control subjects increased their anticipatory muscle activity in the flexor muscles of the arm to control the momentum of the ball at impact. Cerebellar subjects were unable to differentially increase the anticipatory muscle activity across three joints to perform the task successfully. In Experiment 2 (heavy-light-heavy), we tested to see whether the rate of adaptation changed when adapting to a light ball versus a heavy ball. Subjects caught the heavy balls (baseline phase), the light balls (adaptation phase), and then heavy balls again (postadaptation phase). Comparison of rates of adaptation between Experiment 1 and Experiment 2 showed that the rate of adaptation was unchanged whether adapting to a light ball or a heavy ball. Given these findings, we conclude that the cerebellum is important in generating the appropriate anticipatory muscle activity across multiple muscles and modifying it in response to changing demands though trial-and-error practice.

UAVSAR Acquires False-Color Image of Galeras Volcano, Colombia

NASA Image and Video Library

2013-04-03

This false-color image of Colombia Galeras Volcano, was acquired by UAVSAR on March 13, 2013. A highly active volcano, Galeras features a breached caldera and an active cone that produces numerous small to moderate explosive eruptions.

Apparatus and method for inspecting a bearing ball

NASA Technical Reports Server (NTRS)

Bankston, B. F. (Inventor)

1985-01-01

A method and apparatus for inspecting the surface of a ball bearing is disclosed which includes a base having a high friction non-abrasive base scanning surface. A holding device includes a cone-shaped cup recess in which a ball element is received. Air is introduced through a passage to relieve friction between the wall of the recess and the ball element and facilitate rolling of the ball over the high friction base surface. The holding device is moved over the base scanning surface in a predetermined pattern such that the entire surface of the ball element is inspected byan eddy current probe which detects any surface defects.

Analysis on Sealing Reliability of Bolted Joint Ball Head Component of Satellite Propulsion System

NASA Astrophysics Data System (ADS)

Guo, Tao; Fan, Yougao; Gao, Feng; Gu, Shixin; Wang, Wei

2018-01-01

Propulsion system is one of the important subsystems of satellite, and its performance directly affects the service life, attitude control and reliability of the satellite. The Paper analyzes the sealing principle of bolted joint ball head component of satellite propulsion system and discuss from the compatibility of hydrazine anhydrous and bolted joint ball head component, influence of ground environment on the sealing performance of bolted joint ball heads, and material failure caused by environment, showing that the sealing reliability of bolted joint ball head component is good and the influence of above three aspects on sealing of bolted joint ball head component can be ignored.

Process engineering with planetary ball mills.

PubMed

Burmeister, Christine Friederike; Kwade, Arno

2013-09-21

Planetary ball mills are well known and used for particle size reduction on laboratory and pilot scales for decades while during the last few years the application of planetary ball mills has extended to mechanochemical approaches. Processes inside planetary ball mills are complex and strongly depend on the processed material and synthesis and, thus, the optimum milling conditions have to be assessed for each individual system. The present review focuses on the insight into several parameters like properties of grinding balls, the filling ratio or revolution speed. It gives examples of the aspects of grinding and illustrates some general guidelines to follow for modelling processes in planetary ball mills in terms of refinement, synthesis' yield and contamination from wear. The amount of energy transferred from the milling tools to the powder is significant and hardly measurable for processes in planetary ball mills. Thus numerical simulations based on a discrete-element-method are used to describe the energy transfer to give an adequate description of the process by correlation with experiments. The simulations illustrate the effect of the geometry of planetary ball mills on the energy entry. In addition the imaging of motion patterns inside a planetary ball mill from simulations and video recordings is shown.

Determination of the boundary conditions of the grinding load in ball mills

NASA Astrophysics Data System (ADS)

Sharapov, Rashid R.

2018-02-01

The prospects of application in ball mills for grinding cement clinker with inclined partitions are shown. It is noted that ball mills with inclined partitions are more effective. An algorithm is proposed for calculating the power consumed by a ball mill with inclined inter-chamber partitions in which an axial movement of the ball load takes place. The boundary conditions in which the ball load is located are determined. The equations of bounding the grinding load are determined. The behavior of a grinding load is considered in view of the characteristic cross sections. The coordinates of the centers of gravity of the grinding load with a definite step and the shape of the cross sections are determined. It is theoretically shown that grinding load in some parts of the ball mill not only consumes, but also helps to rotate the ball mill. Methods for calculating complex analytical expressions for determining the coordinates of the centers of gravity of the grinding load under the conditions of its longitudinal motion have developed. The carried out researches allow to approach from the general positions to research of behavior of a grinding load in the ball mills equipped with various in-mill devices.

The principal time balls of New Zealand

NASA Astrophysics Data System (ADS)

Kinns, Roger

2017-04-01

Accurate time signals in New Zealand were important for navigation in the Pacific. Time balls at Wellington and Lyttelton were noted in the 1880 Admiralty list of time signals, with later addition of Otago. The time ball service at Wellington started in March 1864 using the first official observatory in New Zealand, but there was no Wellington time ball service during a long period of waterfront redevelopment during the 1880s. The time ball service restarted in November 1888 at a different harbour location. The original mechanical apparatus was used with a new ball, but the system was destroyed by fire in March 1909 and was never replaced. Instead, a time light service was inaugurated in 1912. The service at Lyttelton, near Christchurch, began in December 1876 after construction of the signal station there. It used telegraph signals from Wellington to regulate the time ball. By the end of 1909, it was the only official time ball in New Zealand, providing a service that lasted until 1934. The Lyttelton time ball tower was an iconic landmark in New Zealand that had been carefully restored. Tragically, the tower collapsed in the 2011 earthquakes and aftershocks that devastated Christchurch. A daily time ball service at Port Chalmers, near Dunedin, started in June 1867, initially using local observatory facilities. The service appears to have been discontinued in October 1877, but was re-established in April 1882 as a weekly service, with control by telegraph from Wellington. The service had been withdrawn altogether by the end of 1909. Auckland never established a reliable time ball service, despite provision of a weekly service for mariners by a public-spirited citizen between August 1864 and June 1866. A time ball was finally installed on the Harbour Board building in 1901, but the signal was unreliable and it ceased in 1902. Complaints from ships' masters led to various proposals to re-establish a service. These concluded with erection of a time ball on the new Ferry Building in 1912. The service was finally announced in April 1915, but it was again unreliable and the time ball had been replaced by time lights before the end of that year. The provision of time balls at Wellington, Lyttelton, Port Chalmers and Auckland is described in this paper with particular reference to newspaper announcements.

Stellar Color Regression: A Spectroscopy-based Method for Color Calibration to a Few Millimagnitude Accuracy and the Recalibration of Stripe 82

NASA Astrophysics Data System (ADS)

Yuan, Haibo; Liu, Xiaowei; Xiang, Maosheng; Huang, Yang; Zhang, Huihua; Chen, Bingqiu

2015-02-01

In this paper we propose a spectroscopy-based stellar color regression (SCR) method to perform accurate color calibration for modern imaging surveys, taking advantage of millions of stellar spectra now available. The method is straightforward, insensitive to systematic errors in the spectroscopically determined stellar atmospheric parameters, applicable to regions that are effectively covered by spectroscopic surveys, and capable of delivering an accuracy of a few millimagnitudes for color calibration. As an illustration, we have applied the method to the Sloan Digital Sky Survey (SDSS) Stripe 82 data. With a total number of 23,759 spectroscopically targeted stars, we have mapped out the small but strongly correlated color zero-point errors present in the photometric catalog of Stripe 82, and we improve the color calibration by a factor of two to three. Our study also reveals some small but significant magnitude dependence errors in the z band for some charge-coupled devices (CCDs). Such errors are likely to be present in all the SDSS photometric data. Our results are compared with those from a completely independent test based on the intrinsic colors of red galaxies presented by Ivezić et al. The comparison, as well as other tests, shows that the SCR method has achieved a color calibration internally consistent at a level of about 5 mmag in u - g, 3 mmag in g - r, and 2 mmag in r - i and i - z. Given the power of the SCR method, we discuss briefly the potential benefits by applying the method to existing, ongoing, and upcoming imaging surveys.

Oxone/Fe[superscript 2+] Degradation of Food Dyes: Demonstration of Catalyst-Like Behavior and Kinetic Separation of Color

ERIC Educational Resources Information Center

Nalliah, Ruth E.

2015-01-01

A demonstration of the degradation of food coloring dyes by oxidation via the Fenton reaction can be substituted with a simpler demonstration using the oxidant oxone with iron(II) ions as an activator. The addition of small amounts of solid oxone and iron(II) sulfate to solutions containing mixtures of food coloring results in successive…

COMPARING MID-INFRARED GLOBULAR CLUSTER COLORS WITH POPULATION SYNTHESIS MODELS

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

Barmby, P.; Jalilian, F. F.

2012-04-15

Several population synthesis models now predict integrated colors of simple stellar populations in the mid-infrared bands. To date, the models have not been extensively tested in this wavelength range. In a comparison of the predictions of several recent population synthesis models, the integrated colors are found to cover approximately the same range but to disagree in detail, for example, on the effects of metallicity. To test against observational data, globular clusters (GCs) are used as the closest objects to idealized groups of stars with a single age and single metallicity. Using recent mass estimates, we have compiled a sample ofmore » massive, old GCs in M31 which contain enough stars to guard against the stochastic effects of small-number statistics, and measured their integrated colors in the Spitzer/IRAC bands. Comparison of the cluster photometry in the IRAC bands with the model predictions shows that the models reproduce the cluster colors reasonably well, except for a small (not statistically significant) offset in [4.5] - [5.8]. In this color, models without circumstellar dust emission predict bluer values than are observed. Model predictions of colors formed from the V band and the IRAC 3.6 and 4.5 {mu}m bands are redder than the observed data at high metallicities and we discuss several possible explanations. In agreement with model predictions, V - [3.6] and V - [4.5] colors are found to have metallicity sensitivity similar to or slightly better than V - K{sub s}.« less

Real-time detecting and tracking ball with OpenCV and Kinect

NASA Astrophysics Data System (ADS)

Osiecki, Tomasz; Jankowski, Stanislaw

2016-09-01

This paper presents a way to detect and track ball with using the OpenCV and Kinect. Object and people recognition, tracking are more and more popular topics nowadays. Described solution makes it possible to detect ball based on the range, which is set by the user and capture information about ball position in three dimensions. It can be store in the computer and use for example to display trajectory of the ball.

Telescoping magnetic ball bar test gage

DOEpatents

Bryan, James B.

1984-01-01

A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengageable servo drives which cannot be clutched out. Two gage balls (10, 12) are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit (14) and a rigid member (16, 18, 20, 22, 24). One gage ball (10) is secured by a magnetic socket knuckle assembly (34) which fixes its center with respect to the machine being tested. The other gage ball (12) is secured by another magnetic socket knuckle assembly (38) which is engaged or held by the machine in such manner that the center of that ball (12) is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball (10). As the moving ball (12) executes its trajectory, changes in the radial distance between the centers of the two balls (10, 12) caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly (50, 52, 54, 56, 58, 60) actuated by the parallel reed flexure unit (14). Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball (10) locations, thereby determining the accuracy of the machine.

Promoting ball skills in preschool-age girls.

PubMed

Veldman, Sanne L C; Palmer, Kara K; Okely, Anthony D; Robinson, Leah E

2017-01-01

Evidence supports that girls are less proficient than boys at performing ball skills. This study examined the immediate and long-term effects of a ball skill intervention on preschool-age girls' ball skill performance. Randomized controlled trial. Girls (M age =47.24±7.38 months) were randomly assigned to a high autonomy, mastery-based 9-week motor skill intervention (the Children's Health Activity Motor Program; CHAMP, 540min; n=38) or a control group (free-play; n=16). Ball skill proficiency was assessed at pretest, posttest, and retention test (after 9 weeks) using the object control subscale of the Test of Gross Motor Development - 2nd Edition. Treatment efficacy was examined using linear mixed models. Two models were fit: one for short-term changes (pretest to posttest) and one for long-term changes (pretest to retention). Linear mixed models revealed a significantly time*treatment interaction for both models. Post hoc analysis confirmed that girls in CHAMP experienced significant gains in ball skills from pretest to posttest (p<.001) and pretest to retention (p<.001). Moreover, girls in CHAMP were no different from the control group at pretest (p>.05) but had significantly higher ball skills scores at both posttest (p<.001) and retention (p<.001). This study demonstrates the positive effects of a ball skill intervention (i.e., CHAMP) on improving girls' ball skills both short- and long-term. Findings suggest that early childhood interventions that focus on the development of ball skills in young girls might be an avenue to improve girls' ball skill performance. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Neural Extrapolation of Motion for a Ball Rolling Down an Inclined Plane

PubMed Central

La Scaleia, Barbara; Lacquaniti, Francesco; Zago, Myrka

2014-01-01

It is known that humans tend to misjudge the kinematics of a target rolling down an inclined plane. Because visuomotor responses are often more accurate and less prone to perceptual illusions than cognitive judgments, we asked the question of how rolling motion is extrapolated for manual interception or drawing tasks. In three experiments a ball rolled down an incline with kinematics that differed as a function of the starting position (4 different positions) and slope (30°, 45° or 60°). In Experiment 1, participants had to punch the ball as it fell off the incline. In Experiment 2, the ball rolled down the incline but was stopped at the end; participants were asked to imagine that the ball kept moving and to punch it. In Experiment 3, the ball rolled down the incline and was stopped at the end; participants were asked to draw with the hand in air the trajectory that would be described by the ball if it kept moving. We found that performance was most accurate when motion of the ball was visible until interception and haptic feedback of hand-ball contact was available (Experiment 1). However, even when participants punched an imaginary moving ball (Experiment 2) or drew in air the imaginary trajectory (Experiment 3), they were able to extrapolate to some extent global aspects of the target motion, including its path, speed and arrival time. We argue that the path and kinematics of a ball rolling down an incline can be extrapolated surprisingly well by the brain using both visual information and internal models of target motion. PMID:24940874

Neural extrapolation of motion for a ball rolling down an inclined plane.

PubMed

La Scaleia, Barbara; Lacquaniti, Francesco; Zago, Myrka

2014-01-01

It is known that humans tend to misjudge the kinematics of a target rolling down an inclined plane. Because visuomotor responses are often more accurate and less prone to perceptual illusions than cognitive judgments, we asked the question of how rolling motion is extrapolated for manual interception or drawing tasks. In three experiments a ball rolled down an incline with kinematics that differed as a function of the starting position (4 different positions) and slope (30°, 45° or 60°). In Experiment 1, participants had to punch the ball as it fell off the incline. In Experiment 2, the ball rolled down the incline but was stopped at the end; participants were asked to imagine that the ball kept moving and to punch it. In Experiment 3, the ball rolled down the incline and was stopped at the end; participants were asked to draw with the hand in air the trajectory that would be described by the ball if it kept moving. We found that performance was most accurate when motion of the ball was visible until interception and haptic feedback of hand-ball contact was available (Experiment 1). However, even when participants punched an imaginary moving ball (Experiment 2) or drew in air the imaginary trajectory (Experiment 3), they were able to extrapolate to some extent global aspects of the target motion, including its path, speed and arrival time. We argue that the path and kinematics of a ball rolling down an incline can be extrapolated surprisingly well by the brain using both visual information and internal models of target motion.

Percutaneous Renal Cryoablation: Short-Axis Ice-Ball Margin as a Predictor of Outcome.

PubMed

Ge, Benjamin H; Guzzo, Thomas J; Nadolski, Gregory J; Soulen, Michael C; Clark, Timothy W I; Malkowicz, Stanley B; Wein, Alan J; Hunt, Stephen J; Stavropoulos, S William

2016-03-01

To determine if CT characteristics of intraprocedural ice balls correlate with outcomes after cryoablation. A retrospective review was performed on 63 consecutive patients treated with renal cryoablation. Preprocedural and intraprocedural images were used to identify the size and location of renal tumors and ice balls as well as the tumor coverage and ice-ball margins. Review of follow-up imaging (1 mo and then 3-6-mo intervals) distinguished successful ablations from cases of residual tumor. Patients who underwent successful ablation (n = 50; 79%) had a mean tumor diameter of 2.5 cm (range, 0.9-4.3 cm) and mean ice-ball margin of 0.4 cm (range, 0.2-1.2 cm). Patients with residual tumor (n = 13; 21%) had a mean tumor diameter of 3.8 cm (range, 1.8-4.5 cm) and mean ice-ball margin of -0.4 cm (range, -0.9 to 0.4 cm). Residual and undertreated tumors were larger and had smaller ice-ball margins than successfully treated tumors (P < .01). Ice-ball diameters were significantly smaller after image reformatting (P < .01). Ice-ball margins of 0.15 cm had 90% sensitivity, 92% specificity, and 98% positive predictive value for successful ablation. Success was independent of tumor location or number of cryoprobes. Ice-ball margin and real-time intraprocedural reformatting could be helpful in predicting renal cryoablation outcomes. Although a 0.5-cm margin is preferred, a well-centered ice ball with a short-axis margin greater than 0.15 cm strongly correlated with successful ablation. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

Motion analysis of throwing Boccia balls in children with cerebral palsy.

PubMed

Huang, Po-Chang; Pan, Po-Jung; Ou, Yu-Chih; Yu, Yi-Chen; Tsai, Yung-Shen

2014-02-01

Boccia is a sport suitable for children with cerebral palsy (CP). Throwing Boccia balls requires upper extremity and torso coordination. This study investigated the differences between children with CP and normally developed children regarding throwing patterns of Boccia balls. Thirteen children with bilateral spastic CP and 20 normally developed children participated in this study. The tests in this study were a pediatric reach test and throwing of Boccia balls. A 3D electromagnetic motion tracking system and a force plate were synchronized to record and analyze biomechanical parameters of throwing Boccia balls. The results of the pediatric reach test for participants with CP were significantly worse than those for normally developed participants. The 2 groups of participants did not significantly differ regarding the distance between a thrown Boccia ball and a target ball (jack). Participants with CP demonstrated significantly longer movement duration, smaller amplitude of elbow movement, greater amplitudes of shoulder abduction and flexion, slower maximal velocity of torso flexion and the linear velocity of moving the wrist joint forward, faster maximal velocity of head flexion, and smaller sway ratio compared with normally developed participants when throwing Boccia balls. Participants with CP seemed to mainly use head and shoulder movements to bring the Boccia balls forward with limited torso movement. Normally developed participants brought the Boccia ball forward with faster torso and greater elbow movement while stabilizing head and shoulder movements. Nevertheless, participants with CP did not demonstrate significantly worse performance in the throwing accuracy of Boccia balls. Copyright © 2013 Elsevier Ltd. All rights reserved.

Ball clay

USGS Publications Warehouse

Virta, Robert L.

2010-01-01

The article reports on the global market performance of ball clay in 2009 and presents an outlook for its 2010 performance. Several companies mined ball call in the country including Old Hickey Clay Co., Kentucky-Tennessee Clay Co., and H.C. Spinks Clay Co. Information on the decline in ball clay imports and exports is also presented.

Fizz-Ball Fizzics

ERIC Educational Resources Information Center

Moinester, Murray; Gerland, Lars; Liger-Belair, Gerard; Ocherashvili, Aharon

2012-01-01

We describe the fluid dynamics principles governing the up-down oscillatory cycling of a bubble-covered, low-density, low-mass ball of material (referred to henceforth as a "fizz-ball") immersed inside a glass of bubbling (super-saturated) carbonated liquid. The bubbles serve to desaturate the liquid of excess CO[subscript 2]. The fizz-ball acts…

Does fin coloration signal social status in a dominance hierarchy of the livebearing fish Xiphophorus variatus?

PubMed

Culumber, Zachary W; Monks, Scott

2014-09-01

In each population of the livebearing fish Xiphophorus variatus, only a small portion of the adult males develop bright yellow-red (YR) coloration on the dorsal and caudal fins. Here we characterized the dominance hierarchy in X. variatus and tested whether YR coloration is related to a male's position in the hierarchy and can therefore serve as a reliable cue to rival males. Populations varied considerably in the frequency of YR males. Across all populations, males with YR coloration were significantly larger than the rest of the males in the population. Observations of aggressive interactions among males in small groups in the laboratory revealed a sized-based dominance hierarchy with YR males at the top. Aggression was more common among males of a similar size and fighting increased as male body size differences decreased. However, despite the reliability of YR coloration as a signal of dominance status, males at lower social ranks did not avoid aggression with YR males and YR males did not experience fewer aggressive attacks compared to non-YR males. Our findings demonstrate that fin coloration is a reliable cue of a male's social status but rival males appear to not use this information to avoid potentially costly interactions with dominant males, suggesting that YR fin coloration has not evolved as a cue in agonistic interactions. Copyright © 2014 Elsevier B.V. All rights reserved.

Experimental verification of a tuned inertial mass electromagnetic transducer

NASA Astrophysics Data System (ADS)

Watanabe, Yuta; Sugiura, Keita; Asai, Takehiko

2018-03-01

This research reports on the design and experimental verification of a tuned inertial mass electromagnetic trans- ducer (TIMET) for energy harvesting from vibrating large structures and structural vibration control devices. The TIMET consists of a permanent-magnetic synchronous motor (PMSM), a rotational mass, and a tuning spring. The PMSM and the rotational mass are connected to a ball screw mechanism so that the rotation of the PMSM is synchronized with the rotational mass. And the tuning spring interfaced to the shaft of the ball screw mechanism is connected to the vibrating structure. Thus, through this ball screw mechanism, transla- tional vibration motion of the structure is converted to rotational behavior and mechanical energy is absorbed as electrical energy by the PMSM. Moreover, the amplified equivalent inertial mass effect is obtained by rotating relatively small physical masses. Therefore, when the stiffness of the tuning spring is determined so that the inertial mass resonates with the natural frequency of the vibratory structure, the PMSM rotates more effectively. As a result, the generated energy by the PMSM can be increased. The authors design a prototype of the TIMET and carry out experiments using sine and sine seep waves to show the effectiveness of the tuned inertial mass mechanism. Also, an analytical model of the proposed device is developed using a curve fitting technique to simulate the behavior of the TIMET.

Ball clay

USGS Publications Warehouse

Virta, R.L.

2000-01-01

Part of the 1999 Industrial Minerals Review. The state of the ball clay industry in 1999 is presented. Record highs in the sales and use of ball clay were attained in 1999 due to the continued strength of the U.S. economy. U.S. production was estimated at 1.25 million st for the year, with more than half of that amount mined in Tennessee. Details of the consumption, price, imports, and exports of ball clay in 1999 and the outlook for ball clay over the next few years are provided.

Ball Screw Actuator Including an Axial Soft Stop

NASA Technical Reports Server (NTRS)

Forrest, Steven Talbert (Inventor); Woessner, George (Inventor); Abel, Steve (Inventor); Wingett, Paul T. (Inventor); Hanlon, Casey (Inventor)

2016-01-01

An actuator includes an actuator housing, a ball screw, and an axial soft stop assembly. The ball screw extends through the actuator housing and has a first end and a second end. The ball screw is coupled to receive a drive force and is configured, upon receipt of the drive force, to selectively move in a retract direction and an extend direction. The axial soft stop assembly is disposed within the actuator housing. The axial soft stop assembly is configured to be selectively engaged by the ball screw and, upon being engaged thereby, to translate, with compliance, a predetermined distance in the extend direction, and to prevent further movement of the ball screw upon translating the predetermined distance.

Easy approach to assembling a biomimetic color film with tunable structural colors.

PubMed

Wang, Wentao; Tang, Bingtao; Ma, Wei; Zhang, Jian; Ju, Benzhi; Zhang, Shufen

2015-06-01

The self-assembly of silica microspheres into a close-packed array is a simple method of fabricating three-dimensional photonic crystal structural color films. However, the color is very dull because of the interferences of scattering and background light. In this study, we added a small quantity of surface-modified carbon black (CB) to the system of colloidal silica in n-propanol. The use of n-propanol as a dispersant is beneficial to the rapid development of photonic crystal films during the process of dip-coating. The doping of CB into silica microspheres can absorb background and scattering light, resulting in vivid structural colors.

Behavior of hollow balls containing granules bouncing repeatedly off the ground

NASA Astrophysics Data System (ADS)

Hu, Min; Mu, Qing-song; Luo, Ning; Li, Gang; Peng, Ning-bo

2013-07-01

An experimental study of the behavior of hollow balls filled with some granules (mung beans or millets) bouncing repeatedly off a static flat horizontal surface is presented. We observed that the bounce number of the ball is limited and decreases regularly with an increasing number of granules. Moreover, for two balls containing a different kind of granules, their bounce numbers are basically equal when the two balls have the same mass of granules. While there is no clear relationship between the first rebound height of one ball and the number of granules, there appears an exponential decay of the second rebound height with an increase of the granule number. Furthermore, a two-dimensional numerical model has been created to find out the law of the ball's rebound height and the dissipation law of the granule nested system. A generalized prediction equation to reasonably explain the law of the bounce number has also been proposed.

PDC bit hydraulics design, profile are key to reducing balling

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

Hariharan, P.R.; Azar, J.J.

1996-12-09

Polycrystalline diamond compact (PDC) bits with a parabolic profile and bladed hydraulic design have a lesser tendency to ball during drilling of reactive shales. PDC bits with ribbed or open-face hydraulic designs and those with flat or rounded profiles tended to ball more often in the bit balling experiments conducted. Experimental work also indicates that PDC hydraulic design seems to have a greater influence on bit balling tendency compared to bit profile design. There are five main factors that affect bit balling: formation type, drilling fluid, drilling hydraulics, bit design, and confining pressures. An equation for specific energy showed thatmore » it could be used to describe the efficiency of the drilling process by examining the amount of energy spent in drilling a unit volume of rock. This concept of specific energy has been used herein to correlate with the parameter Rd, a parameter to quantify the degree of balling.« less

Conversion of baryonic fermions into squarks in neutron stars from supersymmetric dark matter Q-balls

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

Shoemaker, Ian M.

2009-08-01

The gauge-mediated model of supersymmetry breaking implies that stable nontopological solitons, Q-balls, could form in the early Universe and comprise the dark matter. It is shown that the inclusion of the effects from gravity-mediation set an upper limit on the size of Q-balls. When in a dense baryonic environment Q-balls grow until reaching this limiting size at which point they fragment into two equal-sized Q-balls. This Q-splitting process will rapidly destroy a neutron star that absorbs even one Q-ball. The new limits on Q-ball dark matter require an ultralight gravitino m{sub 3/2} < or approx. keV, naturally avoiding the gravitinomore » overclosure problem, and providing the minimal supersymmetric standard model with a dark matter candidate where gravitino dark matter is not viable.« less

Effect of Hoop Stress on Ball Bearing Life Prediction

NASA Technical Reports Server (NTRS)

Zaretsky, Erwin V.; August, Richard; Coe, Harold H.

1995-01-01

A finite-element analysis (FEA) of a generic, dimensionally normalized inner race of an angular-contact ball bearing was performed under varying conditions of speed and the press (or interference) fit of the inner-race bore on a journal. The FEA results at the ball-race contact were used to derive an equation from which was obtained the radius of an equivalent cylindrical bearing race with the same or similar hoop stress. The radius of the equivalent cylinder was used to obtain a generalized closed-form approximation of the hoop stresses at the ball-inner-race contact in an angular-contact ball bearing. A life analysis was performed on both a 45- and a 120-mm-bore, angular-contact ball bearing. The predicted lives with and without hoop stress were compared with experimental endurance results obtained at 12000 and 25000 rpm with the 120-mm-bore ball bearing. A life factor equation based on hoop stress is presented.

Ball-morph: definition, implementation, and comparative evaluation.

PubMed

Whited, Brian; Rossignac, Jaroslaw Jarek

2011-06-01

We define b-compatibility for planar curves and propose three ball morphing techniques between pairs of b-compatible curves. Ball-morphs use the automatic ball-map correspondence, proposed by Chazal et al., from which we derive different vertex trajectories (linear, circular, and parabolic). All three morphs are symmetric, meeting both curves with the same angle, which is a right angle for the circular and parabolic. We provide simple constructions for these ball-morphs and compare them to each other and other simple morphs (linear-interpolation, closest-projection, curvature-interpolation, Laplace-blending, and heat-propagation) using six cost measures (travel-distance, distortion, stretch, local acceleration, average squared mean curvature, and maximum squared mean curvature). The results depend heavily on the input curves. Nevertheless, we found that the linear ball-morph has consistently the shortest travel-distance and the circular ball-morph has the least amount of distortion.

Stemless ball valve

NASA Technical Reports Server (NTRS)

Burgess, Kevin (Inventor); Yakos, David (Inventor); Walthall, Bryan (Inventor)

2012-01-01

A stemless ball valve comprising: a right flange; left flange; ball with an axis pin and two travel pins; ball seal on either side of the ball; guide sleeve with inner walls comprising two channels; cartridge guide holder; inner magnetic cartridge; and outer magnetic cartridge. The ball is situated inside of the guide sleeve, and a travel pin is located in each of the two channels. The guide sleeve is situated inside of the cartridge guide holder, which is located adjacent to and outside of the inner magnetic cartridge and secured to the inner magnetic cartridge such that when the inner magnetic cartridge rotates, the cartridge guide holder also rotates. The cartridge guide holder is secured to the guide sleeve such that when the cartridge guide holder rotates, the travel pins move within the channels in the inner walls of the guide sleeve, thereby causing the ball to rotate.

Human Factors Guidelines for Command and Control Systems: Battlefield and Decision Graphics Guidelines

DTIC Science & Technology

1989-03-01

detail in a small area, use achromatic colors ( black , white, and grey) and use chromatic colors for larger panels or for attracting attention. b. Blues...purposes (e.g., to draw the users attention to a total, a broken bar or other important data element). b. Black and white should be used with caution. They...enough to set the bars or columns off from the background and define figure and ground relationships. (2) Use black in small areas and for certain

PULSE COLUMN

DOEpatents

Grimmett, E.S.

1964-01-01

This patent covers a continuous countercurrent liquidsolids contactor column having a number of contactor states each comprising a perforated plate, a layer of balls, and a downcomer tube; a liquid-pulsing piston; and a solids discharger formed of a conical section at the bottom of the column, and a tubular extension on the lowest downcomer terminating in the conical section. Between the conical section and the downcomer extension is formed a small annular opening, through which solids fall coming through the perforated plate of the lowest contactor stage. This annular opening is small enough that the pressure drop thereacross is greater than the pressure drop upward through the lowest contactor stage. (AEC)

Naive Beliefs in Baseball: Systematic Distortion in Perceived Time of Apex for Fly Balls

ERIC Educational Resources Information Center

Shaffer, Dennis M.; McBeath, Michael K.

2005-01-01

When fielders catch fly balls they use geometric properties to optically maintain control over the ball. The strategy provides ongoing guidance without indicating precise positional information concerning where the ball is located in space. Here, the authors show that observers have striking misconceptions about what the motion of projectiles…

Having a Ball with Fitness Balls

ERIC Educational Resources Information Center

McNulty, Betty

2011-01-01

Fitness programs can be greatly enhanced with the addition of fitness balls. They are a fun, challenging, economical, and safe way to incorporate a cardiovascular, strength, and stretching program for all fitness levels in a physical education setting. The use of these balls has become more popular during the last decade, and their benefits and…

Eddy-Current Inspection of Ball Bearings

NASA Technical Reports Server (NTRS)

Bankston, B.

1985-01-01

Custom eddy-current probe locates surface anomalies. Low friction air cushion within cone allows ball to roll easily. Eddy current probe reliably detects surface and near-surface cracks, voids, and material anomalies in bearing balls or other spherical objects. Defects in ball surface detected by probe displayed on CRT and recorded on strip-chart recorder.

An examination of slo-pitch pitching trajectories.

PubMed

Wu, Tom; Gervais, Pierre

2008-01-01

Many slo-pitch coaches and players believe that generating spin on a ball can affect its trajectory. The influence of air resistance on a ball that is thrown at a moderate speed and spin is unclear. The aim of this study was to examine the influence of spin on the ball's trajectory in slo-pitch pitching using both experimental results and ball flight simulations. Fourteen pitchers participated in the study, each of whom threw five backspin and topspin pitches each. Data were collected using standard three-dimensional videography. The horizontal velocity, vertical velocity, angular velocity, release height, and horizontal displacement of the backspin pitches were significantly higher than those of the topspin pitches. The ball flight simulations were developed to examine the influence of the ball spin, and it was concluded that the spin of the ball had a significant effect on the ball's vertical and horizontal displacements. Furthermore, our results suggest that a backspin pitch that reaches the maximum height allowable and lands in the front edge of the strike zone has the steepest slope. The present results add to our understanding of projectile motion and aerodynamics.

Cricket Ball Aerodynamics: Myth Versus Science

NASA Technical Reports Server (NTRS)

Mehta, Rabindra D.; Koga, Demmis J. (Technical Monitor)

2000-01-01

Aerodynamics plays a prominent role in the flight of a cricket ball released by a bowler. The main interest is in the fact that the ball can follow a curved flight path that is not always under the control of the bowler. ne basic aerodynamic principles responsible for the nonlinear flight or "swing" of a cricket ball were identified several years ago and many papers have been published on the subject. In the last 20 years or so, several experimental investigations have been conducted on cricket ball swing, which revealed the amount of attainable swing, and the parameters that affect it. A general overview of these findings is presented with emphasis on the concept of late swing and the effects of meteorological conditions on swing. In addition, the relatively new concept of "reverse" swing, how it can be achieved in practice and the role in it of ball "tampering", are discussed in detail. A discussion of the "white" cricket ball used in last year's World Cup, which supposedly possesses different swing properties compared to a conventional red ball, is also presented.

The Development of using the digital projection method to measure the contact angle of ball screw

NASA Astrophysics Data System (ADS)

Chen, Chun-Jen; Jywe, Wenyuh; Liu, Yu-Chun; Jwo, Hsin-Hong

The ball screw frequently used to drive or translate the parts on the precision machine, such as machine tool and motorized stage. Therefore they were most frequently used on the precision machine, semiconductor equipment, medical instrument and aero industry. The main parts of ball screw are screw, ball and nut. The contact angle between the screw, ball and nut will affect the performance (include loading and noise) and lifecycle of a ball screw. If the actual contact angle and the designed contact angle are not the same, the friction between the ball, screw and nut will increase and it will result in the thermal increase and lifecycle decrease. This paper combines the traditional profile projector and commercial digital camera to build an imaging based and noncontact measurements system. It can implement the contact angle measurement quickly and accurately. Three different pitch angles of ball screws were completed tests in this paper. The angle resolution of this measurement system is about 0.001 degree and its accuracy is about 0.05 degree.

Method and apparatus for jetting, manufacturing and attaching uniform solder balls

DOEpatents

Yost, F.G.; Frear, D.R.; Schmale, D.T.

1999-01-05

An apparatus and process are disclosed for jetting molten solder in the form of balls directly onto all the metallized interconnects lands for a ball grid array package in one step with no solder paste required. Molten solder is jetted out of a grid of holes using a piston attached to a piezoelectric crystal. When voltage is applied to the crystal it expands forcing the piston to extrude a desired volume of solder through holes in the aperture plate. When the voltage is decreased the piston reverses motion creating an instability in the molten solder at the aperture plate surface and thereby forming spherical solder balls that fall onto a metallized substrate. The molten solder balls land on the substrate and form a metallurgical bond with the metallized lands. The size of the solder balls is determined by a combination of the size of the holes in the aperture plate, the duration of the piston pulse, and the displacement of the piston. The layout of the balls is dictated by the location of the hooks in the grid. Changes in ball size and layout can be easily accomplished by changing the grid plate. This invention also allows simple preparation of uniform balls for subsequent supply to BGA users. 7 figs.

How Magnus Bends the Flying Ball - Experimenting and Modeling

NASA Astrophysics Data System (ADS)

Timková, V.; Ješková, Z.

2017-02-01

Students are well aware of the effect of the deflection of sports balls when they have been given a spin. A volleyball, tennis, or table tennis ball served with topspin results in an additional downward force that makes the ball difficult to catch and return. In soccer, the effect of sidespin causes the ball to curve unexpectedly sideways, resulting in a so-called banana kick that can confuse the goalkeeper. These surprising effects attract students' attention such that the motion of sports balls can be used to capture the interest of students towards the physics behind it. However, to study and analyze the motion of a real ball kicked in a playfield is not an easy task. Instead of the large-scale full-size sports ball motion, there can be designed and studied simpler experiments that can be carried out in the classroom. Moreover, digital technologies that are available at schools enable students to collect data from the experiment easily in a reasonable time. The mathematical model based on the analysis of forces acting on the ball flying in the air can be used to simulate the motion in order to understand the basic physical principles of the motion so that the best correspondence may be found.

Ball flight kinematics, release variability and in-season performance in elite baseball pitching.

PubMed

Whiteside, D; McGinnis, R S; Deneweth, J M; Zernicke, R F; Goulet, G C

2016-03-01

The purpose of this study was to quantify ball flight kinematics (ball speed, spin rate, spin axis orientation, seam orientation) and release location variability in the four most common pitch types in baseball and relate them to in-season pitching performance. Nine NCAA Division I pitchers threw four pitching variations (fastball, changeup, curveball, and slider) while a radar gun measured ball speed and a 600-Hz video camera recorded the ball trajectory. Marks on the ball were digitized to measure ball flight kinematics and release location. Ball speed was highest in the fastball, though spin rate was similar in the fastball and breaking pitches. Two distinct spin axis orientations were noted: one characterizing the fastball and changeup, and another, the curveball and slider. The horizontal release location was significantly more variable than the vertical release location. In-season pitching success was not correlated to any of the measured variables. These findings are instructive for inferring appropriate hand mechanics and spin types in each of the four pitches. Coaches should also be aware that ball flight kinematics might not directly relate to pitching success at the collegiate level. Therefore, talent identification and pitching evaluations should encompass other (e.g., cognitive, psychological, and physiological) factors. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Method and apparatus for jetting, manufacturing and attaching uniform solder balls

DOEpatents

Yost, Frederick G.; Frear, Darrel R.; Schmale, David T.

1999-01-01

An apparatus and process for jetting molten solder in the form of balls directly onto all the metallized interconnects lands for a ball grid array package in one step with no solder paste required. Molten solder is jetted out of a grid of holes using a piston attached to a piezoelectric crystal. When voltage is applied to the crystal it expands forcing the piston to extrude a desired volume of solder through holes in the aperture plate. When the voltage is decreased the piston reverses motion creating an instability in the molten solder at the aperture plate surface and thereby forming spherical solder balls that fall onto a metallized substrate. The molten solder balls land on the substrate and form a metallurgical bond with the metallized lands. The size of the solder balls is determined by a combination of the size of the holes in the aperture plate, the duration of the piston pulse, and the displacement of the piston. The layout of the balls is dictated by the location of the hooks in the grid. Changes in ball size and layout can be easily accomplished by changing the grid plate. This invention also allows simple preparation of uniform balls for subsequent supply to BGA users.

Randomized Controlled Trial of Use of the Peanut Ball During Labor.

PubMed

Roth, Cheryl; Dent, Sarah A; Parfitt, Sheryl E; Hering, Sandra L; Bay, R Curtis

2016-01-01

The purpose of this study was to evaluate the efficacy of peanut ball use on duration of first stage labor and pushing time in women who were scheduled for elective induction of labor at ≥39 weeks gestation and planning an epidural. In this randomized controlled trial, women having labor induction and planning a labor epidural were assigned (1:1) to one of two groups: one group used a peanut ball and one group did not. Outcome variables were time spent in first stage labor and time spent pushing. Factors included group assignment (peanut ball, no peanut ball), parity (primiparous, multiparous), and race. Age and maximum oxytocin dose served as covariates. Among women having elective induction with epidural analgesia, use of a peanut ball reduced first stage labor duration for primiparous patients significantly more than multiparous patients, p = 0.018. There was no significant difference in the reduction of length of first stage labor for multiparous women, p = 0.057 with use of the peanut ball. Peanut ball use did not alter length of pushing time for either group, p > 0.05. Use of peanut balls may reduce total labor time to a greater degree in primiparous patients than multiparous patients having elective induction at ≥39 weeks with epidural analgesia.

Training Level Does Not Affect Auditory Perception of The Magnitude of Ball Spin in Table Tennis.

PubMed

Santos, Daniel P R; Barbosa, Roberto N; Vieira, Luiz H P; Santiago, Paulo R P; Zagatto, Alessandro M; Gomes, Matheus M

2017-01-01

Identifying the trajectory and spin of the ball with speed and accuracy is critical for good performance in table tennis. The aim of this study was to analyze the ability of table tennis players presenting different levels of training/experience to identify the magnitude of the ball spin from the sound produced when the racket hit the ball. Four types of "forehand" contact sounds were collected in the laboratory, defined as: Fast Spin (spinning ball forward at 140 r/s); Medium Spin (105 r/s); Slow Spin (84 r/s); and Flat Hit (less than 60 r/s). Thirty-four table tennis players of both sexes (24 men and 10 women) aged 18-40 years listened to the sounds and tried to identify the magnitude of the ball spin. The results revealed that in 50.9% of the cases the table tennis players were able to identify the ball spin and the observed number of correct answers (10.2) was significantly higher (χ 2 = 270.4, p <0.05) than the number of correct answers that could occur by chance. On the other hand, the results did not show any relationship between the level of training/experience and auditory perception of the ball spin. This indicates that auditory information contributes to identification of the magnitude of the ball spin, however, it also reveals that, in table tennis, the level of training does not interfere with the auditory perception of the ball spin.