Science.gov

Sample records for hidden shot balls

  1. Surface modification of titanium using steel slag ball and shot blasting treatment for biomedical implant applications

    NASA Astrophysics Data System (ADS)

    Arifvianto, Budi; Suyitno; Mahardika, Muslim

    2013-08-01

    Surface modification is often performed using grit or shot blasting treatment for improving the performances of biomedical implants. The effects of blasting treatments using steel slag balls and spherical shots on the surface and subsurface of titanium were studied in this paper. The treatments were conducted for 60-300 s using 2-5 mm steel slag balls and 3.18 mm spherical shots. The surface morphology, roughness, and elemental composition of titanium specimens were examined prior to and after the treatments. Irregular and rough titanium surfaces were formed after the treatment with the steel slag balls instead of the spherical shots. The former treatment also introduced some bioactive elements on the titanium surface, but the latter one yielded a harder surface layer. In conclusion, both steel slag ball and shot blasting treatment have their own specialization in modifying the surface of metallic biomaterials. Steel slag ball blasting is potential for improving the osseointegration quality of implants; but the shot blasting is more appropriate for improving the mechanical properties of temporary and load bearing implants, such as osteosynthesis plates.

  2. Estimating distribution of hidden objects with drones: from tennis balls to manatees.

    PubMed

    Martin, Julien; Edwards, Holly H; Burgess, Matthew A; Percival, H Franklin; Fagan, Daniel E; Gardner, Beth E; Ortega-Ortiz, Joel G; Ifju, Peter G; Evers, Brandon S; Rambo, Thomas J

    2012-01-01

    Unmanned aerial vehicles (UAV), or drones, have been used widely in military applications, but more recently civilian applications have emerged (e.g., wildlife population monitoring, traffic monitoring, law enforcement, oil and gas pipeline threat detection). UAV can have several advantages over manned aircraft for wildlife surveys, including reduced ecological footprint, increased safety, and the ability to collect high-resolution geo-referenced imagery that can document the presence of species without the use of a human observer. We illustrate how geo-referenced data collected with UAV technology in combination with recently developed statistical models can improve our ability to estimate the distribution of organisms. To demonstrate the efficacy of this methodology, we conducted an experiment in which tennis balls were used as surrogates of organisms to be surveyed. We used a UAV to collect images of an experimental field with a known number of tennis balls, each of which had a certain probability of being hidden. We then applied spatially explicit occupancy models to estimate the number of balls and created precise distribution maps. We conducted three consecutive surveys over the experimental field and estimated the total number of balls to be 328 (95%CI: 312, 348). The true number was 329 balls, but simple counts based on the UAV pictures would have led to a total maximum count of 284. The distribution of the balls in the field followed a simulated environmental gradient. We also were able to accurately estimate the relationship between the gradient and the distribution of balls. Our experiment demonstrates how this technology can be used to create precise distribution maps in which discrete regions of the study area are assigned a probability of presence of an object. Finally, we discuss the applicability and relevance of this experimental study to the case study of Florida manatee distribution at power plants. PMID:22761712

  3. Estimating Distribution of Hidden Objects with Drones: From Tennis Balls to Manatees

    PubMed Central

    Martin, Julien; Edwards, Holly H.; Burgess, Matthew A.; Percival, H. Franklin; Fagan, Daniel E.; Gardner, Beth E.; Ortega-Ortiz, Joel G.; Ifju, Peter G.; Evers, Brandon S.; Rambo, Thomas J.

    2012-01-01

    Unmanned aerial vehicles (UAV), or drones, have been used widely in military applications, but more recently civilian applications have emerged (e.g., wildlife population monitoring, traffic monitoring, law enforcement, oil and gas pipeline threat detection). UAV can have several advantages over manned aircraft for wildlife surveys, including reduced ecological footprint, increased safety, and the ability to collect high-resolution geo-referenced imagery that can document the presence of species without the use of a human observer. We illustrate how geo-referenced data collected with UAV technology in combination with recently developed statistical models can improve our ability to estimate the distribution of organisms. To demonstrate the efficacy of this methodology, we conducted an experiment in which tennis balls were used as surrogates of organisms to be surveyed. We used a UAV to collect images of an experimental field with a known number of tennis balls, each of which had a certain probability of being hidden. We then applied spatially explicit occupancy models to estimate the number of balls and created precise distribution maps. We conducted three consecutive surveys over the experimental field and estimated the total number of balls to be 328 (95%CI: 312, 348). The true number was 329 balls, but simple counts based on the UAV pictures would have led to a total maximum count of 284. The distribution of the balls in the field followed a simulated environmental gradient. We also were able to accurately estimate the relationship between the gradient and the distribution of balls. Our experiment demonstrates how this technology can be used to create precise distribution maps in which discrete regions of the study area are assigned a probability of presence of an object. Finally, we discuss the applicability and relevance of this experimental study to the case study of Florida manatee distribution at power plants. PMID:22761712

  4. Severe craniocerebral trauma with sequelae caused by Flash-Ball® shot, a less-lethal weapon: Report of one case and review of the literature.

    PubMed

    Hiquet, Jean; Gromb-Monnoyeur, Sophie

    2016-07-01

    The use of Flash-Ball® as a non-lethal weapon by several special units within the police and police forces started in France in 1995. Little literature is available concerning injuries caused by Flash-Ball® shooting. However, we report the case of a healthy 34-year-old male victim of a Flash-Ball® shooting during a riot following a sports event. This young man presented serious craniocerebral injuries with a left temporal fracture, moderate cerebral oedema, fronto-temporal haemorrhagic contusion along with an extra-dural hematoma and subarachnoid hemorrhage requiring neurological and rehabilitation care for two months leaving important sequelae. Although the risk is obviously lower than with firearms, Flash-Ball® is nonetheless potentially lethal and may cause serious physical injuries, particularly after a shot to the head. PMID:26130748

  5. The hidden cost of coaching: intentional training of shot adequacy discrimination in basketball hampers utilization of informative incidental cues.

    PubMed

    Suárez Cadenas, Ernesto; Cárdenas, David; Sánchez Delgado, Guillermo; Perales, José C

    2015-02-01

    The goal was to identify the advantages and disadvantages of using intentional guidance to teach to discriminate between good and bad circumstances to shoot in basketball. A simulated shot-adequacy learning task was developed, in which participants were asked to decide, in each trial, whether the player in possession of the ball should shoot or not. After each decision, they received feedback on their response (determined by five cues: Opposition, Rebound, Balance, Alternative, and Distance). 65 naïve participants (M age = 18.6 yr., SD = 1.3) were divided into two groups. The Incidental group received no guiding instructions. The Intentional group was instructed to utilize four of the five cues. The Distance cue was kept incidental for both groups. Participants effectively incorporated the cues into their decisions. Guidance had a markedly different effect across cues. The Intentional group utilized Distance less efficiently than the Incidental group, i.e., intentional instructions on the other four cues nearly blocked the utilization of Distance. PMID:25668077

  6. The Hardest Straight-in Pool Shot

    ERIC Educational Resources Information Center

    Mabry, Rick

    2010-01-01

    When playing pool or billiards, a player often has the opportunity to make a "straight-in" shot, that is, one in which the cue ball, the object ball, and the target (e.g., a pocket) are collinear. With the distance from the cue ball to the target assumed fixed, the relative difficulty is here explored of shots taken at varying positions of the…

  7. Dense Plasma Focus: physics and applications (radiation material science, single-shot disclosure of hidden illegal objects, radiation biology and medicine, etc.)

    NASA Astrophysics Data System (ADS)

    Gribkov, V. A.; Miklaszewski, R.; Paduch, M.; Zielinska, E.; Chernyshova, M.; Pisarczyk, T.; Pimenov, V. N.; Demina, E. V.; Niemela, J.; Crespo, M.-L.; Cicuttin, A.; Tomaszewski, K.; Sadowski, M. J.; Skladnik-Sadowska, E.; Pytel, K.; Zawadka, A.; Giannini, G.; Longo, F.; Talab, A.; Ul'yanenko, S. E.

    2015-03-01

    The paper presents some outcomes obtained during the year of 2013 of the activity in the frame of the International Atomic Energy Agency Co-ordinated research project "Investigations of Materials under High Repetition and Intense Fusion-Relevant Pulses". The main results are related to the effects created at the interaction of powerful pulses of different types of radiation (soft and hard X-rays, hot plasma and fast ion streams, neutrons, etc. generated in Dense Plasma Focus (DPF) facilities) with various materials including those that are counted as perspective ones for their use in future thermonuclear reactors. Besides we discuss phenomena observed at the irradiation of biological test objects. We examine possible applications of nanosecond powerful pulses of neutrons to the aims of nuclear medicine and for disclosure of hidden illegal objects. Special attention is devoted to discussions of a possibility to create extremely large and enormously diminutive DPF devices and probabilities of their use in energetics, medicine and modern electronics.

  8. 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.

  9. The Problem of Shot Selection in Basketball

    PubMed Central

    Skinner, Brian

    2012-01-01

    In basketball, every time the offense produces a shot opportunity the player with the ball must decide whether the shot is worth taking. In this article, I explore the question of when a team should shoot and when they should pass up the shot by considering a simple theoretical model of the shot selection process, in which the quality of shot opportunities generated by the offense is assumed to fall randomly within a uniform distribution. Within this model I derive an answer to the question “how likely must the shot be to go in before the player should take it?” and I show that this lower cutoff for shot quality depends crucially on the number of shot opportunities remaining (say, before the shot clock expires), with larger demanding that only higher-quality shots should be taken. The function is also derived in the presence of a finite turnover rate and used to predict the shooting rate of an optimal-shooting team as a function of time. The theoretical prediction for the optimal shooting rate is compared to data from the National Basketball Association (NBA). The comparison highlights some limitations of the theoretical model, while also suggesting that NBA teams may be overly reluctant to shoot the ball early in the shot clock. PMID:22295109

  10. The problem of shot selection in basketball.

    PubMed

    Skinner, Brian

    2012-01-01

    In basketball, every time the offense produces a shot opportunity the player with the ball must decide whether the shot is worth taking. In this article, I explore the question of when a team should shoot and when they should pass up the shot by considering a simple theoretical model of the shot selection process, in which the quality of shot opportunities generated by the offense is assumed to fall randomly within a uniform distribution. Within this model I derive an answer to the question "how likely must the shot be to go in before the player should take it?" and I show that this lower cutoff for shot quality f depends crucially on the number n of shot opportunities remaining (say, before the shot clock expires), with larger n demanding that only higher-quality shots should be taken. The function f(n) is also derived in the presence of a finite turnover rate and used to predict the shooting rate of an optimal-shooting team as a function of time. The theoretical prediction for the optimal shooting rate is compared to data from the National Basketball Association (NBA). The comparison highlights some limitations of the theoretical model, while also suggesting that NBA teams may be overly reluctant to shoot the ball early in the shot clock. PMID:22295109

  11. 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.

  12. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2006-01-01

    In 2005, four companies including H.C. Spinks Clay, Kentucky-Tennessee Clay, Old Hickory Clay and Unimin mined ball clay in four states. Based on a preliminary survey of the ball clay industry, production reached 1.32 Mt valued at $53.3 million. Tennessee was the leading ball clay producer state with 61% of domestic production, followed by Texas, Mississippi and Kentucky.

  13. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2011-01-01

    The article discusses the latest developments in the global ball clay mining industry, particularly in the U.S., as of June 2011. It cites several firms that are involved in ball clay mining in the U.S., including HC Spins Clay Co. Inc., the Imerys Group and Old Hickory Clay Co. Among the products made from ball clay are ceramic tiles, sanitaryware, as well as fillers, extenders and binders.

  14. 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.

  15. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2013-01-01

    Four companies — H.C. Spinks Clay Co., Inc., Imerys, Old Hickory Clay Co. and Unimin Corp. — mined ball clay in five U.S. states in 2012. Production, on the basis of preliminary data, was 900 kt (992,000 st), with an estimated value of $42.3 million. This was a slight increase in tonnage from 886 kt (977,000 st), with a value of $40.9 million in 2011. Tennessee was the leading ball clay producing state, with 63 percent of domestic production, followed by Texas, Mississippi, Kentucky and Indiana. Reported ball clay production from Indiana probably was fire clay rather than ball clay. About 69 percent of total ball clay production was airfloat, 20 percent was crude and 11 percent was water-slurried.

  16. A review on the basketball jump shot.

    PubMed

    Okazaki, Victor H A; Rodacki, André L F; Satern, Miriam N

    2015-06-01

    The ability to shoot an effective jump shot in the sport of basketball is critical to a player's success. In an attempt to better understand the aspects related to expert performance, researchers have investigated successful free throws and jump shots of various basketball players and identified movement variables that contribute to their success. The purpose of this study was to complete a systematic review of the scientific literature on the basketball free throw and jump shot for the purpose of revealing the critical components of shooting that coaches, teachers, and players should focus on when teaching, learning, practising, and performing a jump shot. The results of this review are presented in three sections: (a) variables that affect ball trajectory, (b) phases of the jump shot, and PMID:26102462

  17. Holy balls!

    NASA Astrophysics Data System (ADS)

    Truscott, Tadd; Belden, Jesse

    2011-11-01

    Why can some balls walk on water while others cannot? We investigate the rebound dynamics of elastic spheres impacting on a free-surface. Several variables determine whether or not a sphere will bounce when impacting a free-surface including velocity, impact angle, size and elasticity. Stiff elastic spheres, such as a racquetball, successfully skip at low impact angles and high velocities, but tend not to bounce when the impact angle becomes too large. However, the more compliant Waboba (WAter BOuncing BAll) bounces marvelously even at very high impact angles. Unlike a stiffer ball, the Waboba flattens out quickly as it is forming a cavity. The cavity lip forms a ramp and the flattened ball then skips off the water surface. We demonstrate how this phenomenon surprisingly resembles a skipping stone. Using high-speed video we explore the rebound dynamics for various values of elasticity, velocity, angle and size and determine when an object will bounce off the water surface.

  18. 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.

  19. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2007-01-01

    The article offers information on ball clay. Among the companies that mine ball clay in the U.S. are H.C. Spinks Clay, Kentucky-Tennessee Clay and Old Hickory Clay. In 2006, an estimated 1.2 million tons of the mineral was sold or used domestically and exported. Forty-percent of the total sales is accounted for ceramic floor and wall tile followed by sanitaryware and miscellaneous ceramics. Its average value was $ 45 per ton in 2006.

  20. Precise timing when hitting falling balls

    PubMed Central

    Brenner, Eli; Driesen, Ben; Smeets, Jeroen B. J.

    2014-01-01

    People are extremely good at hitting falling balls with a baseball bat. Despite the ball's constant acceleration, they have been reported to time hits with a standard deviation of only about 7 ms. To examine how people achieve such precision, we compared performance when there were no added restrictions, with performance when looking with one eye, when vision was blurred, and when various parts of the ball's trajectory were hidden from view. We also examined how the size of the ball and varying the height from which it was dropped influenced temporal precision. Temporal precision did not become worse when vision was blurred, when the ball was smaller, or when balls falling from different heights were randomly interleaved. The disadvantage of closing one eye did not exceed expectations from removing one of two independent estimates. Precision was higher for slower balls, but only if the ball being slower meant that one saw it longer before the hit. It was particularly important to see the ball while swinging the bat. Together, these findings suggest that people time their hits so precisely by using the changing elevation throughout the swing to adjust the bat's movement to that of the ball. PMID:24904380

  1. Precise timing when hitting falling balls.

    PubMed

    Brenner, Eli; Driesen, Ben; Smeets, Jeroen B J

    2014-01-01

    People are extremely good at hitting falling balls with a baseball bat. Despite the ball's constant acceleration, they have been reported to time hits with a standard deviation of only about 7 ms. To examine how people achieve such precision, we compared performance when there were no added restrictions, with performance when looking with one eye, when vision was blurred, and when various parts of the ball's trajectory were hidden from view. We also examined how the size of the ball and varying the height from which it was dropped influenced temporal precision. Temporal precision did not become worse when vision was blurred, when the ball was smaller, or when balls falling from different heights were randomly interleaved. The disadvantage of closing one eye did not exceed expectations from removing one of two independent estimates. Precision was higher for slower balls, but only if the ball being slower meant that one saw it longer before the hit. It was particularly important to see the ball while swinging the bat. Together, these findings suggest that people time their hits so precisely by using the changing elevation throughout the swing to adjust the bat's movement to that of the ball. PMID:24904380

  2. Increased distance of shooting on basketball jump shot.

    PubMed

    Okazaki, Victor Hugo Alves; Rodacki, André Luiz Félix

    2012-01-01

    The present study analyzed the effect of increased distance on basketball jump shot outcome and performance. Ten male expert basketball players were filmed and a number of kinematic variables analyzed during jump shot that were performed from three conditions to represent close, intermediate and far distances (2.8, 4.6, and 6.4m, respectively). Shot accuracy decreased from 59% (close) to 37% (far), in function of the task constraints (p < 0.05). Ball release height decreased (p < 0.05) from 2.46 m (close) to 2.38m (intermediate) and to 2.33m (long). Release angle also decreased (p < 0.05) when shot was performed from close (78.92°) in comparison to intermediate distances (65.60°). While, ball release velocity increased (p < 0.05) from 4.39 m/s (close) to 5.75 m·s(-1) (intermediate) to 6.89 m·s(-1) (far). These changes in ball release height, angle and velocity, related to movement performance adaptations were suggested as the main factors that influence jump shot accuracy when distance is augmented. Key pointsThe increased distance leads to greater spatial con-straint over shot movement that demands an adapta-tion of the movement for the regulation of the accu-racy and the impulse generation to release the ball.The reduction in balls release height and release angle, in addition to the increase in balls release ve-locity, were suggested as the main factors that de-creased shot accuracy with the distance increased.Players should look for release angles of shooting that provide an optimal balls release velocity to im-prove accuracy. PMID:24149195

  3. 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

  4. Structure of Flame Balls at Low Lewis Number (SOFBALL) Video

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Structure of Flame Balls at Low Lewis (SOFBALL) experiment, was run on Space Shuttle Columbia in 2003 for STS-107. The experiment tested various fuel-oxygen-inert gas mixtures in microgravity to produce flame balls, which are spherical steady flames that reveal combustion processes hidden by the volatile effects of gravity on Earth. In this video, a hydrogen-oxygen-sulfur hexafluoride gas mixture produced nine flame balls, the most ever created at once, one of which lasted 81 minutes making it the longest lasting flame ball ever burned in space.

  5. Four Ball Best Ball 1

    PubMed Central

    Pollard, Geoff; Pollard, Graham

    2010-01-01

    In this paper a four-ball-best-ball (4BBB) model for pairs of golf players is set up. The 4BBB match-play scoring system is seen to satisfy a basic requirement of fairness. It is shown that it is not strictly possible to rate individual players as 4BBB players. However, a (reasonably broad) class of individual players is identified such that it is possible to rate them individually as 4BBB players. The capacity of an individual to play birdies is seen to be a very important determinant in being a successful member of a 4BBB pair, but there are other minor factors as well. Consideration is given to equal and unequal 4BBB pairs. The transitive law is seen to apply for 4BBB pairs. Thus, if pair A is better than pair B, and pair B is better than pair C, then pair A must be better than pair C. Correspondingly, if pair A is equal to pair B, and pair B is equal to pair C, then pair A is equal to pair C. Consideration is given to some strategic issues in 4BBB match-play golf. For example, the conditions under which a player should take a greater risk and have a higher probability of obtaining a bogie in order to achieve a higher probability of scoring a birdie, are determined. Also, the conditions under which a player, noting that his partner is about to have a ‘bad’ hole and score only a par or a bogie, should ‘play safe’, are determined. Thirdly, players who can interact in certain ways are seen to have an advantage over those pairs that cannot do this. Finally, one pair’s optimal strategy when they see that their opponents are about to score a par or a bogie, but not a birdie, is analyzed. Key points A model for four-ball-best-ball match-play golf is established, and used to show that, although there can be other factors, the capacity of an individual to play birdies is a very important determinant in that player being a successful member of a four-ball-best-ball pair. Although it is not possible in general to rate play-ers individually as 4BBB players, a

  6. Four ball best ball 1.

    PubMed

    Pollard, Geoff; Pollard, Graham

    2010-01-01

    In this paper a four-ball-best-ball (4BBB) model for pairs of golf players is set up. The 4BBB match-play scoring system is seen to satisfy a basic requirement of fairness. It is shown that it is not strictly possible to rate individual players as 4BBB players. However, a (reasonably broad) class of individual players is identified such that it is possible to rate them individually as 4BBB players. The capacity of an individual to play birdies is seen to be a very important determinant in being a successful member of a 4BBB pair, but there are other minor factors as well. Consideration is given to equal and unequal 4BBB pairs. The transitive law is seen to apply for 4BBB pairs. Thus, if pair A is better than pair B, and pair B is better than pair C, then pair A must be better than pair C. Correspondingly, if pair A is equal to pair B, and pair B is equal to pair C, then pair A is equal to pair C. Consideration is given to some strategic issues in 4BBB match-play golf. For example, the conditions under which a player should take a greater risk and have a higher probability of obtaining a bogie in order to achieve a higher probability of scoring a birdie, are determined. Also, the conditions under which a player, noting that his partner is about to have a 'bad' hole and score only a par or a bogie, should 'play safe', are determined. Thirdly, players who can interact in certain ways are seen to have an advantage over those pairs that cannot do this. Finally, one pair's optimal strategy when they see that their opponents are about to score a par or a bogie, but not a birdie, is analyzed. Key pointsA model for four-ball-best-ball match-play golf is established, and used to show that, although there can be other factors, the capacity of an individual to play birdies is a very important determinant in that player being a successful member of a four-ball-best-ball pair.Although it is not possible in general to rate play-ers individually as 4BBB players, a class of indi

  7. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2012-01-01

    Four companies — H.C. Spinks Clay Co., Inc., Imerys Group, Old Hickory Clay Co., and Unimin Corp. — mined ball clay in four states in 2011. Production, on the basis of preliminary data, was 940 kt (1.04 million st) with an estimated value of $44.2 million. This is a 3-percent increase in tonnage from 912 kt (1.01 million st) with a value of $41.3 million that was produced in 2010. Tennessee was the leading producing state with 63 percent of domestic production, followed by Texas, Mississippi and Kentucky. About 69 percent of production was airfloat, 20 percent was crude and 11 percent was water-slurried.

  8. Babies and shots

    MedlinePlus

    ... article discusses how to ease the pain of shots for babies. ... Parents often wonder how to make shots less painful for their babies. Nearly all immunizations (also called vaccinations) need to be given into the muscle or under the skin ...

  9. Allergy Shots (For Parents)

    MedlinePlus

    ... Shots Help Allergy shots help the body build immunity to specific allergens, thus eventually preventing or lessening ... the immune system to safely adjust and build immunity to the allergens. This is called the buildup ...

  10. Get Important Shots

    MedlinePlus

    ... a Plan Keep a Record The Basics The Basics: Overview Adults need to get shots (vaccines) just like kids do. ... Previous section Overview 2 of 5 sections The Basics: Other Shots Do I need any other shots to help me stay healthy? ...

  11. Babies and shots

    MedlinePlus

    ... next one less scary. Some doctors use a pain-relieving spray or cream before giving the shot. WHEN THE SHOT IS BEING GIVEN Put pressure on the area before the shot is given. Stay calm and do not let the child see if ...

  12. Birth Control Shot

    MedlinePlus

    ... to a year after they stop getting the birth control shot. However, the shot does not cause permanent loss of fertility and most women can get pregnant once they stop getting the shot. previous continue Who Uses It? Every method of birth control should be considered in light of what works ...

  13. Bouncing Balls that Spin

    ERIC Educational Resources Information Center

    Knipp, Peter

    2008-01-01

    When a ball bounces elastically against a floor, the vertical component (v[subscript y]) of the velocity of the ball's mass-center changes sign. This is a special case of the elastic collision of two balls (i.e., two objects, neither of which is much more massive than the other), in which case the balls' post-collision relative velocity (=…

  14. 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.

  15. Hidden earthquakes

    SciTech Connect

    Stein, R.S.; Yeats, R.S.

    1989-06-01

    Seismologists generally look for earthquakes to happen along visible fault lines, e.g., the San Andreas fault. The authors maintain that another source of dangerous quakes has been overlooked: the release of stress along a fault that is hidden under a fold in the earth's crust. The paper describes the differences between an earthquake which occurs on a visible fault and one which occurs under an anticline and warns that Los Angeles greatest earthquake threat may come from a small quake originating under downtown Los Angeles, rather than a larger earthquake which occurs 50 miles away at the San Andreas fault.

  16. 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…

  17. The Goldenrod Ball Gall

    ERIC Educational Resources Information Center

    Fischer, Richard B.

    1974-01-01

    The paper presents a generalized life history of the goldenrod ball gall, a ball-shaped swelling found almost exclusively on the Canada goldenrod, Solidago canadensis, and caused by a peacock fly know as Eurosta soldiaginis. (KM)

  18. Dynamics of the basketball shot with application to the free throw.

    PubMed

    Okubo, H; Hubbard, M

    2006-12-01

    A completely general three-dimensional dynamic model is presented for the motion of basketball shots that may contact the rim, the backboard, the bridge between the rim and board, and possibly the board and the bridge simultaneously. Non-linear ordinary differential equations with six degrees of freedom describe the ball angular velocity and ball centre position. The model includes radial ball compliance and damping and contains five sub-models: purely gravitational flight, and ball-rim, ball-bridge, ball-board, and ball-bridge-board contact. Each contact sub-model has both slipping and non-slipping motions. Switching between the sub-models depends on the reaction force at, and velocity of, the contact point. Although the model can be used to study shots from any point on the court, we here use it to study the sets of free throw release angle, velocity, angular velocity, and lateral deviation angle that result in success (capture), as well as underhand free throws and those using an under-inflated ball. Free throw shots with larger backspin, lower inflation pressures, and underhand release conditions are shown to result in larger capture percentages. PMID:17101533

  19. 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…

  20. 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.

  1. Shot-put kinematics

    NASA Astrophysics Data System (ADS)

    DeLuca, R.

    2005-11-01

    The problem of the optimum throw in the shot-put discipline is analysed by relaxing the assumption that the height H, from which the athlete releases the shot, does not depend on the angle θ which the arm of the putter makes with the horizontal axis. In this context, the kinematics of the shot-put is studied and results are compared with the traditional analysis, which considers the height H, the angle θ and the modulus V0 of the initial velocity of the metal sphere as independent parameters.

  2. Duration of mentally simulated movement before and after a golf shot.

    PubMed

    Koyama, Satoshi; Tsuruhara, Kiyoshi; Yamamoto, Yuji

    2009-02-01

    This report examined the temporal consistency of preshot routines and the temporal similarity and variability between simulated movements before and after a shot. 12 male amateur golfers ages 32 to 69 years (M=53.4, SD=10.5) were assigned into two groups according to their handicaps: skilled (M=4.0 handicap, SD=3.1) and less-skilled (M=16.0 handicap, SD=6.5). They performed their shots mentally from their preshot routines to the points when the balls came to rest, then performed the same shots physically and again recalled the shots mentally. For each of four par-three holes, participants' performances were filmed, and the durations of mental and actual shots were timed. Analysis showed that the skilled golfers had more consistent preshot routines in actual movement, and they also had longer durations for the ball flight phase than the less-skilled golfers in simulated movement. The present findings support the importance of consistent preshot routines for high performance in golf, however, the duration of simulated movements was underestimated both before and after the shots. This also suggests that skilled golfers attend to performance goals both before and after shots to execute their shots under proceduralized control and to correct their movements for their next shot. PMID:19425472

  3. Shots for Safety

    MedlinePlus

    ... and Aging Shots For Safety Flu Pneumococcal Disease Tetanus and Diphtheria Shingles Measles, Mumps, and Rubella Side ... may need a second one to stay protected. Tetanus and Diphtheria Tetanus (sometimes called lockjaw) is caused ...

  4. 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.

  5. The bounce of a ball

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    1999-03-01

    In this paper, the dynamics of a bouncing ball is described for several common ball types having different bounce characteristics. Results are presented for a tennis ball, a baseball, a golf ball, a superball, a steel ball bearing, a plasticene ball, and a silly putty ball. The plasticene ball was studied as an extreme case of a ball with a low coefficient of restitution (in fact zero, since the collision is totally inelastic) and the silly putty ball was studied because it has unusual elastic properties. The first three balls were studied because of their significance in the physics of sports. For each ball, a dynamic hysteresis curve is presented to show how energy is lost during and after the collision. The measurement technique is quite simple, it is suited for undergraduate laboratory experiments, and it may provide a useful method to test and approve balls for major sporting events.

  6. Aerodynamics of Wiffle Balls

    NASA Astrophysics Data System (ADS)

    Utvich, Alexis; Jemmott, Colin; Logan, Sheldon; Rossmann, Jenn

    2003-11-01

    A team of undergraduate students has performed experiments on Wiffle balls in the Harvey Mudd College wind tunnel facility. Wiffle balls are of particular interest because they can attain a curved trajectory with little or no pitcher-imparted spin. The reasons behind this have not previously been quantified formally. A strain gauge device was designed and constructed to measure the lift and drag forces on the Wiffle ball; a second device to measure lift and drag on a spinning ball was also developed. Experiments were conducted over a range of Reynolds numbers corresponding to speeds of roughly 0-40 mph. Lift forces of up to 0.2 N were measured for a Wiffle ball at 40 mph. This is believed to be due to air flowing into the holes on the Wiffle ball in addition to the effect of the holes on external boundary layer separation. A fog-based flow visualization system was developed in order to provide a deeper qualitative understanding of what occurred in the flowfield surrounding the ball. The data and observations obtained in this study support existing assumptions about Wiffle ball aerodynamics and begin to elucidate the mechanisms involved in Wiffle ball flight.

  7. Quartz ball valve

    NASA Technical Reports Server (NTRS)

    Goetz, C.; Ingle, W. M. (Inventor)

    1980-01-01

    A ball valve particularly suited for use in the handling of highly corrosive fluids is described. It is characterized by a valve housing formed of communicating segments of quartz tubing, a pair of communicating sockets disposed in coaxial alignment with selected segments of tubing for establishing a pair of inlet ports communicating with a common outlet port, a ball formed of quartz material supported for displacement between the sockets and configured to be received alternately thereby, and a valve actuator including a rod attached to the ball for selectively displacing the ball relative to each of the sockets for controlling fluid flow through the inlet ports.

  8. Ball Bearing Mechanics

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1981-01-01

    Load-deflection relationships for different types of elliptical contacts such as those found in a ball bearing are developed. Simplified expressions that allow quick calculations of deformation to be made simply from a knowledge of the applied load, the material properties, and the geometry of the contacting elements are presented. Ball bearings subjected to radial, thrust and combined ball loads are analyzed. A design criterion for fatigue life of ball bearings is developed. The section of a satisfactory lubricant, as well as describing systems that provide a constant flow of lubricant to the contact, is considered.

  9. Large gauged Q balls

    NASA Astrophysics Data System (ADS)

    Anagnostopoulos, K. N.; Axenides, M.; Floratos, E. G.; Tetradis, N.

    2001-12-01

    We study Q balls associated with local U(1) symmetries. Such Q balls are expected to become unstable for large values of their charge because of the repulsion mediated by the gauge force. We consider the possibility that the repulsion is eliminated through the presence in the interior of the Q ball of fermions with charge opposite to that of the scalar condensate. Another possibility is that two scalar condensates of opposite charge form in the interior. We demonstrate that both these scenarios can lead to the existence of classically stable, large, gauged Q balls. We present numerical solutions, as well as an analytical treatment of the ``thin-wall'' limit.

  10. Birth of ball lightning

    NASA Astrophysics Data System (ADS)

    Lowke, J. J.; Smith, D.; Nelson, K. E.; Crompton, R. W.; Murphy, A. B.

    2012-10-01

    Many observations of ball lightning report a ball of light, about 10 cm in diameter, moving at about walking speed, lasting up to 20 s and frequently existing inside of houses and even aeroplanes. The present paper reports detailed observations of the initiation or birth of ball lightning. In two cases, navigation crew of aircraft saw ball lightning form at the windscreen inside the cockpit of their planes. In the first case, the ball lightning occurred during a thunderstorm, with much lightning activity outside of the plane. In the second case, large "horns" of electrical corona were seen outside of the plane at the surface of the radome, just prior to the formation of the ball lightning. A third case reports ball lightning formed inside of a house, during a thunderstorm, at a closed glass window. It is proposed, based on two-dimensional calculations of electron and ion transport, that ball lightning in these cases is driven and formed by atmospheric ions impinging and collecting on the insulating surface of the glass or Perspex windows. This surface charge can produce electric fields inside of the cockpit or room sufficient to sustain an electric discharge. Charges of opposite sign to those outside of the window accumulate on the inside surface of the glass, leaving a ball of net charge moving inside of the cockpit or room to produce a pulsed discharge on a microsecond time scale.

  11. Physics of ball sports

    NASA Astrophysics Data System (ADS)

    Cohen, C.; Clanet, C.

    2016-06-01

    Ball sports have been part of human history for thousands of years [1]. Nowadays, 13 of them are part of the Olympic games (badminton, basketball, beach volley, football/soccer, golf, handball, hockey, rugby, table tennis, tennis, volleyball, water polo, ice hockey). All these games differ by launcher (hand, club, racket, bat), ball (size, shape and mass), pitch size and number of players. These differences induce different ball velocities. Apart from the velocities and the way to maximize them, we discuss in this article the ball trajectories and their impact on the size of sports fields.

  12. Apparent impact: the hidden cost of one-shot trades

    NASA Astrophysics Data System (ADS)

    Mastromatteo, Iacopo

    2015-06-01

    We study the problem of the execution of a moderate size order in an illiquid market within the framework of a solvable Markovian model. We suppose that in order to avoid impact costs, a trader decides to execute her order through a unique trade, waiting for enough liquidity to accumulate at the best quote. We find that despite the absence of a proper price impact, such trader faces an execution cost arising from a non-vanishing correlation among volume at the best quotes and price changes. We characterize analytically the statistics of the execution time and its cost by mapping the problem to the simpler one of calculating a set of first-passage probabilities on a semi-infinite strip. We finally argue that price impact cannot be completely avoided by conditioning the execution of an order to a more favorable liquidity scenario.

  13. Ball Collision Experiments

    ERIC Educational Resources Information Center

    Cross, R.

    2015-01-01

    Experiments are described on collisions between two billiard balls and between a bat and a ball. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.

  14. Borner Ball Neutron Detector

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Bonner Ball Neutron Detector measures neutron radiation. Neutrons are uncharged atomic particles that have the ability to penetrate living tissues, harming human beings in space. The Bonner Ball Neutron Detector is one of three radiation experiments during Expedition Two. The others are the Phantom Torso and Dosimetric Mapping.

  15. Great balls of fire

    NASA Astrophysics Data System (ADS)

    Stenhoff, Mark; reader01; jjherrera

    2014-03-01

    In reply to the physicsworld.com news article “Burning soil fuels ball lightning” (9 January, http://ow.ly/tl8aO) on evidence that a burning core of soil acts as an energy source for ball lightning.

  16. Biomechanical analysis of the jump shot in basketball.

    PubMed

    Struzik, Artur; Pietraszewski, Bogdan; Zawadzki, Jerzy

    2014-09-29

    Basketball players usually score points during the game using the jump shot. For this reason, the jump shot is considered to be the most important element of technique in basketball and requires a high level of performance. The aim of this study was to compare the biomechanical characteristics of the lower limbs during a jump shot without the ball and a countermovement jump without an arm swing. The differences between variables provide information about the potential that an athlete can utilise during a game when performing a jump shot. The study was conducted among 20 second-league basketball players by means of a Kistler force plate and the BTS SMART system for motion analysis. The variables measured included the take-off time, mean power, peak power, relative mean power, jump height, maximum landing force and calculated impact ratio. Surprisingly, more advantageous variables were found for the jump shot. This finding suggests a very high performance level in the jump shot in the studied group and a maximum utilisation of their motor abilities. Both types of jumps were characterised by high mean and peak power values and average heights. The high forces at landing, which result in considerable impact ratios, may have prompted the studied group to land softly. Use of the countermovement jump without an arm swing is recommended to assess and predict the progression of player's jumping ability. PMID:25414741

  17. Stemless ball valve

    NASA Technical Reports Server (NTRS)

    Burgess, Kevin (Inventor); Yakos, David (Inventor); Walthall, Bryan (Inventor)

    2011-01-01

    A stemless ball valve comprising two flanges and a ball with a channel, two axis pins and two travel pins. One end of each axis and travel pin is fixedly attached to the ball, and the other end of each axis pin is lodged into a notch in the first or second flange such that the axis pin is allowed to rotate in the notch. The guide sleeve comprises two channels, and one end of each travel pin is situated within one of the two channels in the guide sleeve. An outer magnetic cartridge causes the inner magnetic cartridge and guide sleeve to rotate, and when the guide sleeve rotates, the travel pins move up and down within the channels in the guide sleeve. The movement of the travel pins within the channels in the guide sleeve causes the ball to rotate, thereby opening and closing the ball valve.

  18. Tunguska dark matter ball

    NASA Astrophysics Data System (ADS)

    Froggatt, C. D.; Nielsen, H. B.

    2015-04-01

    It is suggested that the Tunguska event in June 1908 was due to a cm-large ball of a condensate of bound states of 6 top and 6 antitop quarks containing highly compressed ordinary matter. Such balls are supposed to make up the dark matter as we earlier proposed. The expected rate of impact of this kind of dark matter ball with the earth seems to crudely match a time scale of 200 years between the impacts. The main explosion of the Tunguska event is explained in our picture as material coming out from deep within the earth, where it has been heated and compressed by the ball penetrating to a depth of several thousand km. Thus the effect has some similarity with volcanic activity as suggested by Kundt. We discuss the possible identification of kimberlite pipes with earlier Tunguska-like events. A discussion of how the dark matter balls may have formed in the early universe is also given.

  19. Happy Balls, Unhappy Balls, and Newton's Cradle

    ERIC Educational Resources Information Center

    Kagan, David

    2010-01-01

    The intricacies of Newton's Cradle are well covered in the literature going as far back as the time of Newton! These discussions generally center on the highly elastic collisions of metal spheres. Thanks to the invention of happy and unhappy balls, you can build and study the interaction of less elastic systems (see Fig. 1).

  20. Compact Q-balls

    NASA Astrophysics Data System (ADS)

    Bazeia, D.; Losano, L.; Marques, M. A.; Menezes, R.; da Rocha, R.

    2016-07-01

    In this work we deal with non-topological solutions of the Q-ball type in two space-time dimensions, in models described by a single complex scalar field that engenders global symmetry. The main novelty is the presence of stable Q-balls solutions that live in a compact interval of the real line and appear from a family of models controlled by two distinct parameters. We find analytical solutions and study their charge and energy, and show how to control the parameters to make the Q-balls classically and quantum mechanically stable.

  1. Kids Guide to Shots

    MedlinePlus

    ... that they usually don't get a very bad case of it. Milder cases mean fewer spots and less itching. Shots are given by injection with a needle. A syringe (say: seh-RINJ) holds the liquid vaccine, and the needle has a hole in it ...

  2. Taking the Shot

    ERIC Educational Resources Information Center

    Grayson, Jennifer

    2011-01-01

    In today's high-pressure IT world, almost every opportunity comes hidden inside a problem. And when it comes to "greening" a data center, the problems can be especially daunting, given institutional inertia, budgetary concerns, politics, and more. For CIOs looking to notch up a win with a leaner, greener data center, the key to success often lies…

  3. 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.

  4. Quartz ball value

    NASA Technical Reports Server (NTRS)

    Goetz, C.; Ingle, W. M.

    1979-01-01

    Quartz ball valve consisting of two quartz joints sealed back-to-back and seated in quartz sockets perform at temperatures of up to 1,250 C and in corrosive chemical environments without contamination or degradation.

  5. Super Ball Bot

    NASA Video Gallery

    Tensegrity Robot: Child's Play or Space Tech? Super Ball Bot is an all-in-one landing and mobility platform based on tensegrity structures, allowing for lower-cost, and more reliable planetary miss...

  6. Passive Ball Capture Joint

    NASA Technical Reports Server (NTRS)

    Cloyd, Richard A. (Inventor); Bryan, Thomas C. (Inventor)

    2003-01-01

    A passive ball capture joint has a sleeve with a plurality of bores distributed about a circumference thereof and formed therethrough at an acute angle relative to the sleeve's longitudinal axis. A spring-loaded retainer is slidingly fitted in each bore and is biased such that, if allowed, will extend at least partially into the sleeve to retain a ball therein. A ring, rotatably mounted about the bores, has an interior wall defining a plurality of shaped races that bear against the spring-loaded retainers. A mechanized rotational force producer is coupled to the ring. The ring can be rotated from a first position (that presses the retainers into the sleeve to lock the ball in place) to a second position (that allows the retainers to springback out of the sleeve to release the ball).

  7. Introduction to ball bearings

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1981-01-01

    The purpose of a ball bearing is to provide a relative positioning and rotational freedom while transmitting a load between two structures, usually a shaft and a housing. For high rotational speeds (e.g., in gyroscope ball bearings) the purpose can be expanded to include rotational freedom with practically no wear in the bearing. This condition can be achieved by separating the bearing parts with a coherent film of fluid known as an elastohydrodynamic film. This film can be maintained not only when the bearing carries the load on a shaft, but also when the bearing is preloaded to position the shaft to within micro- or nano-inch accuracy and stability. Background information on ball bearings is provided, different types of ball bearings and their geometry and kinematics are defined, bearing materials, manufacturing processes, and separators are discussed. It is assumed, for the purposes of analysis, that the bearing carries no load.

  8. Aerodynamics of sports balls

    NASA Astrophysics Data System (ADS)

    Mehta, R. D.

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  9. Aerodynamics of sports balls

    NASA Technical Reports Server (NTRS)

    Mehta, R. D.

    1985-01-01

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  10. The influence of football boot construction on ball velocity and deformation

    NASA Astrophysics Data System (ADS)

    Taha, Zahari; Azri Aris, Mohd; Hasnun Arif Hassan, Mohd

    2013-12-01

    Research on the biomechanical properties of football boots has received little scientific attention. Recently, modern and scientific football boots has been developed that afford excellent ball control, shooting and running ability. Different constructions of football boot deliver different velocity and deformation of the ball. In this study, three commercially available football boots were compared during kicking in terms of, ball velocity and deformation of the ball. A subject performed three repetitive shots of the ball into the net for each football boot model. The footballer's foot and the ball velocity were recorded using a high speed camera. From the recorded video, the kicking velocity, ball velocity and ball deformation were measured. Based on the foot and ball velocity data, the Coefficient of Restitution (COR) was calculated. The results obtained show the COR value varies with different boots (CORBootA = 0.89, CORBootB = 0.59, CORBootC = 0.47) thus delivers different ball velocities at same kicking foot velocity (Uleg = 14 ms-1). It is apparent that the Boot A was made with the best upper material (Teijin synthetic leather), design and also construction of the boot.

  11. 76 FR 58108 - Safety Zone; Ryder Cup Captain's Duel Golf Shot, Chicago River, Chicago, IL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Ryder Cup Captain's Duel Golf Shot, Chicago... restrict vessels from a portion of the Chicago River during a golfing event that will involve hitting golf... the public and their vessels from the hazards associated with golf balls being hit from land onto...

  12. ZAPP shot summary

    SciTech Connect

    Loisel, Guillaume Pascal

    2015-10-01

    This was the second Z Astrophysical Plasma Properties (ZAPP) fundamental science shot series of 2015. ZAPP experiments measure fundamental properties of atoms in plasmas to solve the following important astrophysical puzzles: Why can’t we accurately model the opacity of Fe at the convection zone boundary in the Sun? How accurate are the photoionization models used to interpret data from xray satellite observations? and Why doesn’t spectral fitting provide the correct properties for White Dwarfs?

  13. Problem of hidden variables

    NASA Astrophysics Data System (ADS)

    Santos, Emilio

    1992-10-01

    The problem of hidden variables in quantum mechanics is formalized as follows. A general or contextual (noncontextual) hidden-variables theory is defined as a mapping f: Q×M → C (f: Q→C) where Q is the set of projection operators in the appropriate (quantum) Hilbert space, M is the set of maximal Boolean subalgebras of Q and C is a (classical) Boolean algebra. It is shown that contextual (noncontextual) hidden-variables always exist (do not exist).

  14. Ball lightning burn.

    PubMed

    Selvaggi, Gennaro; Monstrey, Stan; von Heimburg, Dennis; Hamdi, Mustapha; Van Landuyt, Koen; Blondeel, Phillip

    2003-05-01

    Ball lightning is a rare physical phenomenon, which is not yet completely explained. It is similar to lightning but with different, peculiar characteristics. It can be considered a mix of fire and electricity, concentrated in a fireball with a diameter of 20-cm that most commonly appears suddenly, even in indoor conditions, during a thunderstorm. It moves quickly for several meters, can change direction, and ultimately disappears. During a great storm, a 28-year-old man and his 5-year-old daughter sustained burn wounds after ball lightning came from the outdoors through a chimney. These two patients demonstrated signs of fire and electrical injuries. The father, who lost consciousness, sustained superficial second-degree burn wounds bilaterally on the zygomatic area and deep second-degree burn wounds on his right hand (total body surface area, 4%). His daughter demonstrated superficial second-degree burn wounds on the left part of the face and deep second-degree and third-degree burn wounds (total body surface area, 30%) on the left neck, both upper arms, and the back. In this article, the authors report the first two cases of burn injuries resulting from ball lightning contact indoors. The literature on this rare phenomenon is reviewed to elucidate the nature of ball lightning. Emphasis is placed on the nature of injuries after ball lightning contact, the therapy used, and the long-term complications. PMID:12792547

  15. Lead shot toxicity to passerines

    USGS Publications Warehouse

    Vyas, N.B.; Spann, J.W.; Heinz, G.H.

    2001-01-01

    This study evaluated the toxicity of a single size 7.5 lead shot to passerines. No mortalities or signs of plumbism were observed in dosed cowbirds (Molothrus ater) fed a commercial diet, but when given a more natural diet, three of 10 dosed birds died within 1 day. For all survivors from which shot were recovered, all but one excreted the shot within 24 h of dosing, whereas, the dead birds retained their shot. Shot erosion was significantly greater (P < 0.05) when weathered shot were ingested compared to new shot, and the greatest erosion was observed in those birds that died (2.2-9.7%). Blood lead concentrations of birds dosed with new shot were not significantly different (P=0.14) from those of birds exposed to weathered shot. Liver lead concentrations of birds that died ranged from 71 to 137 ppm, dry weight. Despite the short amount of time the shot was retained, songbirds may absorb sufficient lead to compromise their survival.

  16. Hex ball torque test

    NASA Technical Reports Server (NTRS)

    Robinson, B. A.; Foster, C. L.

    1986-01-01

    A series of torque tests were performed on four flight-type hex ball universal joints in order to characterize and determine the actual load-carrying capability of this device. The universal joint is a part of manual actuation rods for scientific instruments within the Hubble Space Telescope. It was found that the hex ball will bind slightly during the initial load application. This binding did not affect the function of the universal joint, and the units would wear-in after a few additional loading cycles. The torsional yield load was approximately 50 ft-lb, and was consistent among the four test specimens. Also, the torque required to cause complete failure exceeded 80 ft-lb. It is concluded that the hex ball universal joint is suitable for its intended applications.

  17. Confinement of Coulomb balls

    SciTech Connect

    Arp, O.; Block, D.; Klindworth, M.; Piel, A.

    2005-12-15

    A model for the confinement of the recently discovered Coulomb balls is proposed. These spherical three-dimensional plasma crystals are trapped inside a rf discharge under gravity conditions and show an unusual structural order in complex plasmas. Measurements of the thermophoretic force acting on the trapped dust particles and simulations of the plasma properties of the discharge are presented. The proposed model of confinement considers thermophoretic, ion-drag, and electric field forces, and shows excellent agreement with the observations. The findings suggest that self-confinement does not significantly contribute to the structural properties of Coulomb balls.

  18. The Physics of Shot Towers

    ERIC Educational Resources Information Center

    Lipscombe, Trevor C.; Mungan, Carl E.

    2012-01-01

    In the late 18th and throughout the 19th century, lead shot for muskets was prepared by use of a shot tower. Molten lead was poured from the top of a tower and, during its fall, the drops became spherical under the action of surface tension. In this article, we ask and answer the question: "How does the size of the lead shot depend on the height…

  19. Lead shot poisons bald eagles

    SciTech Connect

    Cohn, J.P.

    1985-09-01

    This article describes the controversy between the US Fish and Wildlife Service, the National Wildlife Federation and the increased mortality of bald eagles. The eagles are being poisoned by preying on waterfowl which have ingested lead shot or have been wounded by shot and not recovered. The controversy has resulted in the establishment of new criteria for so-called non-toxic shot waterfowl hunting.

  20. The Physics of Shot Towers

    NASA Astrophysics Data System (ADS)

    Lipscombe, Trevor C.; Mungan, Carl E.

    2012-04-01

    In the late 18th and throughout the 19th century, lead shot for muskets was prepared by use of a shot tower. Molten lead was poured from the top of a tower and, during its fall, the drops became spherical under the action of surface tension. In this article, we ask and answer the question: How does the size of the lead shot depend on the height of the tower? In the process, we explain the basic technology underlying an important historical invention (the shot tower) and use simple physics (Newtonian mechanics and the thermodynamic laws of cooling) to model its operation.

  1. Balls and Spheres

    ERIC Educational Resources Information Center

    Szekely, George

    2011-01-01

    This article describes an art lesson that allows students to set up and collect sphere canvases. Spheres move art away from a rectangular canvas into a dimension that requires new planning and painting. From balls to many other spherical canvases that bounce, roll, float and fly, art experiences are envisioned by students. Even if adults recognize…

  2. Centrifugal shot blast system

    SciTech Connect

    1998-02-01

    This report describes a demonstration of Concrete cleaning, Inc., modified centrifugal shot blast technology to remove the paint coating from concrete flooring. This demonstration is part of the Chicago Pile-5 (CP-5) Large-Scale Demonstration Project (LSDP) sponsored by the US Department of Energy (DOE), office of Science and Technology (OST), Deactivation and Decommissioning Focus Area (DDFA). The objective of the LSDP is to select and demonstrate potentially beneficial technologies at the Argonne National Laboratory-East (ANL) CP-5 Research Reactor. The purpose of the LSDP is to demonstrate that using innovative and improved decontamination and decommissioning (D and D) technologies from various sources can result in significant benefits, such as decreased cost and increased health and safety, as compared with baseline D and D technologies. Potential markets exist for the innovative centrifugal shot blast system at the following sites: Fernald Environmental Management Project, Los Alamos, Nevada, Oak Ridge Y-12 and K-25, Paducah, Portsmouth Gaseous Diffusion site, and the Savannah River Site. This information is based on a revision to the OST Linkage Tables dated August 4, 1997.

  3. 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.

  4. 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.

  5. Stemless Ball Valve

    NASA Technical Reports Server (NTRS)

    Burgess, Robert K.; Yakos, David; Walthall, Bryan

    2012-01-01

    This invention utilizes a new method of opening and closing a ball valve. Instead of rotating the ball with a perpendicular stem (as is the case with standard ball valves), the ball is rotated around a fixed axis by two guide pins. This innovation eliminates the leak point that is present in all standard ball valves due to the penetration of an actuation stem through the valve body. The VOST (Venturi Off-Set-Technology) valve has been developed for commercial applications. The standard version of the valve consists of an off-set venturi flow path through the valve. This path is split at the narrowest portion of the venturi, allowing the section upstream from the venturi to be rotated. As this rotation takes place, the venturi becomes restricted as one face rotates with respect to the other, eventually closing off the flow path. A spring-loaded seal made of resilient material is embedded in the upstream face of the valve, making a leak-proof seal between the faces; thus a valve is formed. The spring-loaded lip seal is the only seal that can provide a class six, or bubble-tight, seal against the opposite face of the valve. Tearing action of the seal by high-velocity gas on this early design required relocation of the seal to the downstream face of the valve. In the stemless embodiment of this valve, inner and outer magnetic cartridges are employed to transfer mechanical torque from the outside of the valve to the inside without the use of a stem. This eliminates the leak path caused by the valve stems in standard valves because the stems penetrate through the bodies of these valves.

  6. Shot Planning and Analysis Tools

    SciTech Connect

    Casey, A; Beeler, R; Conder, A; Fallejo, R; Flegel, M; Hutton, M; Jancaitis, K; Lakamsani, V; Potter, D; Reisdorf, S; Tappero, J; Whitman, P; Carr, W; Liao, Z

    2011-07-25

    Shot planning and analysis tools (SPLAT) integrate components necessary to help achieve a high over-all operational efficiency of the National Ignition Facility (NIF) by combining near and long-term shot planning, final optics demand and supply loops, target diagnostics planning, and target fabrication requirements. Currently, the SPLAT project is comprised of two primary tool suites for shot planning and optics demand. The shot planning component provides a web-based interface to selecting and building a sequence of proposed shots for the NIF. These shot sequences, or 'lanes' as they are referred to by shot planners, provide for planning both near-term shots in the Facility and long-term 'campaigns' in the months and years to come. The shot planning capabilities integrate with the Configuration Management Tool (CMT) for experiment details and the NIF calendar for availability. Future enhancements will additionally integrate with target diagnostics planning and target fabrication requirements tools. The optics demand component is built upon predictive modelling of maintenance requirements on the final optics as a result of the proposed shots assembled during shot planning. The predictive models integrate energetics from a Laser Performance Operations Model (LPOM), the status of the deployed optics as provided by the online Final Optics Inspection system, and physics-based mathematical 'rules' that predict optic flaw growth and new flaw initiations. These models are then run on an analytical cluster comprised of forty-eight Linux-based compute nodes. Results from the predictive models are used to produce decision-support reports in the areas of optics inspection planning, optics maintenance exchanges, and optics beam blocker placement advisories. Over time, the SPLAT project will evolve to provide a variety of decision-support and operation optimization tools.

  7. Moon shots for management.

    PubMed

    Hamel, Gary

    2009-02-01

    In May 2008, a group of management scholars and senior executives worked to define an agenda for management during the next 100 years. The so-called renegade brigade, led by Gary Hamel, included academics, such as C.K. Prahalad, Peter Senge, and Jeffrey Pfeffer; new-age thinkers, like James Surowiecki; and progressive CEOs, such as Whole Foods' John Mackey, W.L. Gore's Terri Kelly, and IDEO's Tim Brown. What drew them together was a set of shared beliefs about the importance of management and a sense of urgency about reinventing it for a new era. The group's first task was to compile a roster of challenges that would focus the energies of management innovators around the world. Accordingly, in this article, Hamel (who has set up the Management Lab, a research organization devoted to management innovation) outlines 25 "moon shots"--ambitious goals that managers should strive to achieve and in the process create Management 2.0. Topping the list is the imperative of extending management's responsibilities beyond just creating shareholder value. To do so will require both reconstructing the field's philosophical foundations so that work serves a higher purpose and fully embedding the ideas of community and citizenship into organizations. A number of challenges focus on ameliorating the toxic effects of hierarchy. Others focus on better ways to unleash creativity and capitalize on employees' passions. Still others seek to transcend the limitations of traditional patterns of management thinking. Not all the moon shots are new, but many tackle issues that are endemic in large organizations. Their purpose is to inspire new solutions to long-simmering problems by making every company as genuinely human as the people who work there. PMID:19266704

  8. Golf in the Wind: Exploring the Effect of Wind on the Accuracy of Golf Shots

    NASA Astrophysics Data System (ADS)

    Yaghoobian, Neda; Mittal, Rajat

    2015-11-01

    Golf play is highly dependent on the weather conditions with wind being the most significant factor in the unpredictability of the ball landing position. The direction and strength of the wind alters the aerodynamic forces on a ball in flight, and consequently its speed, distance and direction of travel. The fact that local wind conditions on any particular hole change over times-scales ranging all the way from a few seconds to minutes, hours and days introduces an element of variability in the ball trajectory that is not understood. Any such analysis is complicated by the effect of the local terrestrial and vegetation topology, as well as the inherent complexity of golf-ball aerodynamics. In the current study, we use computational modeling to examine the unpredictability of the shots under different wind conditions over Hole-12 at the Augusta National Golf Club, where the Masters Golf Tournament takes place every year. Despite this being the shortest hole on the course, the presence of complex vegetation canopy around this hole introduces a spatial and temporal variability in wind conditions that evokes uncertainty and even fear among professional golfers. We use our model to examine the effect of wind direction and wind-speed on the accuracy of the golf shots at this hole and use the simulations to determine the key aerodynamic factors that affect the accuracy of the shot.

  9. The hidden universe

    SciTech Connect

    Disney, M.

    1985-01-01

    Astronomer Disney has followed a somewhat different tack than that of most popular books on cosmology by concentrating on the notion of hidden (as in not directly observable by its own radiation) matter in the universe.

  10. Allergy Shots: Could They Help Your Allergies?

    MedlinePlus

    ... substance that you are allergic to (called the allergen). Common allergens include mold and pollen from grasses, ragweed and ... shot. Allergy shots help your body fight the allergen. When you get shots that contain the allergen, ...

  11. Ball Lightning Investigations

    NASA Astrophysics Data System (ADS)

    Bychkov, V. L.; Nikitin, A. I.; Dijkhuis, G. C.

    Ball lightning (BL) researches' review and theoretical models of three different authors are presented. The general review covers investigations from 1838 until the present day, and includes a discussion on observation data, experimental modeling, and theoretical approaches. Section 6.1 is written by Bychkov and Nikitin; authors of the sections 6.2, 6.3 and 6.4 are, respectively, Bychkov, Nikitin and Dijkhuis.

  12. 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.

  13. Physics in a Glitter Ball

    ERIC Educational Resources Information Center

    Trikosko, Walter

    2011-01-01

    Maui Toys' Water Bouncer (Fig. 1) is a water-filled ball containing glitter. Buy one and put it on your desk and students can't keep their hands off of it. Pitch the ball in the air giving it a quick spin. When you catch it you will see a sparkling vortex. Twist the ball around different ways and the angular momentum of the fluid keeps the axis of…

  14. Polyurethane retainers for ball bearings

    NASA Technical Reports Server (NTRS)

    Christy, R. I.

    1973-01-01

    Evaluation of a new ball bearing retainer material is reported. A special composite polyurethane foam ball retainer has been developed that has virtually zero wear, is chemically inert to hydrocarbon lubricants, and stores up to 60 times as much lubricant per unit volume as the most commonly used retainer material, cotton phenolic. This new retainer concept shows promise of years of ball bearing operation without reoiling, based on life testing in high vacuum.

  15. SunShot Identity Video

    SciTech Connect

    Le, Minh; Resch, Rhone

    2014-05-19

    Highlights of the SunShot program, the national targets for the program, and the "all of the above" approach to achieving those goals through research, tech transfer, permitting, tax incentives, and a comprehensive approach to installation.

  16. SunShot Identity Video

    ScienceCinema

    Le, Minh; Resch, Rhone

    2014-06-05

    Highlights of the SunShot program, the national targets for the program, and the "all of the above" approach to achieving those goals through research, tech transfer, permitting, tax incentives, and a comprehensive approach to installation.

  17. The Floating Ball Paradox

    NASA Astrophysics Data System (ADS)

    Wente, Henry C.

    2008-11-01

    In capillary theory there are two kinds of surface tension. There is the surface tension at the interface between two immiscible fluids. Thomas Young [9] also allowed for there to be a surface tension associated with a liquid-solid interface. He proceeded to use a balance of forces argument to derive the well-known contact angle condition along a liquid-liquid-solid intersection. The validity of this argument has recently been called into question by R. Finn [6]. A floating ball experiment discussed in that paper leads to an apparent paradox. We address this issue.

  18. Rotary Ball Locking Mechanism

    NASA Technical Reports Server (NTRS)

    Holman, Earl V.

    1990-01-01

    Ball locking mechanism links input drive shaft to output shaft and disengages two shafts from each other when it locks output shaft at either of two fixed angular positions. Part of drive system turning microwave antenna 143.5 degrees between stowage and employment orientations and holds it at either orientation without back-loading drive motor and gears. Angular interval and dimensions modified for use in robotic or other actuators in which desirable to "rest" drive trains while locking actuators at fixed positions.

  19. Atmospheric Ball Plasma Interactions

    NASA Astrophysics Data System (ADS)

    Wurden, C. J. V.; Wurden, G. A.

    2008-11-01

    Free-floating atmospheric pressure copper hydroxyl ball plasmas have been studied in air and helium atmospheres, using still and high speed photography (up to 20,000 fps), collimated photodiodes, and spectroscopy. A fine boundary layer between the greenish Cu-OH cloud, and the air, is orange in color. However, when the discharge is initiated into a helium atmosphere, the boundary layer is no longer visible, suggesting that the visible boundary was caused by interactions with oxygen. We have studied scaling of the 10-cm diameter ball plasmas with both the size of the water bucket, and the applied discharge voltage, over the range of 500-5000 volts. When looking at the initial spider-leg breakdown above the water surface, the ratio of H-alpha to H-beta lines suggests a temperature of ˜0.3 eV. This is also consistent with the presence of molecular lines of OH, and perhaps CuOH2 in the rising cloud. The cloud is affected by, but can penetrate through an aluminum window screen mesh.

  20. Holy Balls!: Part Deux

    NASA Astrophysics Data System (ADS)

    Belden, Jesse; Jandron, Michael; Truscott, Tadd

    2012-11-01

    A Waboba® (WAter BOuncing BAll) demonstrates remarkable water skipping behavior, even at relatively large impact angles. The highly compliant nature of these elastic spheres results in significant deformation into a disk-like shape upon impact. The increased wetted area and force coefficient generates a large hydrodynamic force that more readily lifts the ball off the water surface. However, elasticity introduces some surprising phenomena, such as material waves that propagate on the sphere and interact with the water cavity. Depending upon impact conditions, material waves may propagate in various directions combining to create multiple modes of deformation and complicated fluid-structure interactions. Furthermore, the timescales of deformation and wave propagation depend on the material properties and impact conditions. In this talk, we will discuss skipping regimes in terms of impact parameters and material properties and relate failed skipping behavior to the structure-fluid interaction caused by deformation. The critical timescales for deformation, wave propagation and collision will be related to the relevant physical parameters of the problem.

  1. 76 FR 59421 - Proposed Information Collection; Approval Procedures for Nontoxic Shot and Shot Coatings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ... Shot Coatings AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice; request for comments... Procedures for Nontoxic Shot and Shot Coatings, 50 CFR 20.134. Service Form Number(s): None. Type of Request... market approved nontoxic shot types or nontoxic shot coatings. Respondent's Obligation: Required...

  2. Kinematic adjustments in the basketball jump shot against an opponent.

    PubMed

    Rojas, F J; Cepero, M; Oña, A; Gutierrez, M

    2000-10-01

    The aim of this study was to analyse the adjustments in technique made by a basketball player when shooting against an opponent. The subjects used consisted of 10 professional basketball players of the Spanish First Division League. Three-dimensional motion analysis based on video recordings (50 Hz) was used to obtain the kinematic characteristics of basketball jump shots with and without an opponent. It was found that when performing against an opponent the release angle of the ball increased, the flight time was reduced and postural adjustments as determined by the angles at the knee and shoulder increased, all significantly. There were several other non-significant differences that helped to interpret the changes in technique imposed by the presence of an opponent. It was suggested that when shooting with an opponent, players attempted to release the ball more quickly and from a greater height. This strategy will lessen the chance of the opponent intercepting the ball. It was concluded that the differences noted in the technical execution of the skill had implications for practice. It was suggested that training would benefit from practice with an opponent for at least some of the time to condition players to the demands which they were more likely to meet in the game situation. PMID:11083144

  3. Reflections on a Bouncing Ball

    ERIC Educational Resources Information Center

    Rohr, Jim; Lopez, Veronica; Rohr, Tyler

    2014-01-01

    While observing the bounce heights of various kinds of sports balls dropped from different heights onto a variety of surfaces, we thought of the following question: Could measurements of drop and bounce heights of balls of different diameters, but of the same material, falling from different heights, but on the same surface, be expressed by a…

  4. Behaviour of a Bouncing Ball

    ERIC Educational Resources Information Center

    Cross, Rod

    2015-01-01

    The bounce of a ball is a seemingly innocuous event that can be used to illustrate many aspects of elementary and even advanced mechanics. Both normal and oblique bounces on a rigid surface are considered in this article, emphasizing qualitative features of the bounce process. If the ball bounces at an oblique angle then it can slide throughout…

  5. Hazing: Hidden Campus Crime.

    ERIC Educational Resources Information Center

    Hollmann, Barbara B.

    2002-01-01

    Initiation traditions and rites of passage are important for group and team membership, but the violent behavior and alcohol abuse involved in hazing constitute serious campus crime. This article helps campus administrators to develop new strategies for attacking the hidden crime of hazing. (Contains 32 references.) (Author)

  6. Structure of laboratory ball lightning

    NASA Astrophysics Data System (ADS)

    Ito, Tsuyohito; Tamura, Tomoya; Cappelli, Mark A.; Hamaguchi, Satoshi

    2009-12-01

    Trajectories of self-sustained laboratory ball lightning, generated by arc discharges with silicon, are investigated for understanding the possibility of buoyant flight. Extremely low apparent densities are found, nearly approaching that of standard air. The freely buoyant balls are observed to survive for about 0.1 s, with significantly buoyant balls surviving for several seconds. These ball lightning objects are found to have a density and size that can easily allow them to be carried by a gentle breeze of a few meters per second. The results are interpreted by a model that is an extension of that first proposed by Abrahamson and Dinniss [J. Abrahamson and J. Dinniss, Nature (London) 403, 519 (2000)]. The buoyant behavior of ball lightning seen in our experiments is believed to arise as a result of the formation of a nanoparticle oxide network growing from a molten silicon core.

  7. Structure of laboratory ball lightning.

    PubMed

    Ito, Tsuyohito; Tamura, Tomoya; Cappelli, Mark A; Hamaguchi, Satoshi

    2009-12-01

    Trajectories of self-sustained laboratory ball lightning, generated by arc discharges with silicon, are investigated for understanding the possibility of buoyant flight. Extremely low apparent densities are found, nearly approaching that of standard air. The freely buoyant balls are observed to survive for about 0.1 s, with significantly buoyant balls surviving for several seconds. These ball lightning objects are found to have a density and size that can easily allow them to be carried by a gentle breeze of a few meters per second. The results are interpreted by a model that is an extension of that first proposed by Abrahamson and Dinniss [J. Abrahamson and J. Dinniss, Nature (London) 403, 519 (2000)]. The buoyant behavior of ball lightning seen in our experiments is believed to arise as a result of the formation of a nanoparticle oxide network growing from a molten silicon core. PMID:20365306

  8. Shot-noise Fano factor

    NASA Astrophysics Data System (ADS)

    Rajdl, Kamil; Lansky, Petr

    2015-11-01

    A variability measure of the times of uniform events based on a shot-noise process is proposed and studied. The measure is inspired by the Fano factor, which we generalize by considering the time-weighted influence of the events given by a shot-noise response function. The sequence of events is assumed to be an equilibrium renewal process, and based on this assumption we present formulas describing the behavior of the variability measure. The formulas are derived for a general response function, restricted only by some natural conditions, but the main focus is given to the shot noise with exponential decrease. The proposed measure is analyzed and compared with the Fano factor.

  9. Shot-noise Fano factor.

    PubMed

    Rajdl, Kamil; Lansky, Petr

    2015-11-01

    A variability measure of the times of uniform events based on a shot-noise process is proposed and studied. The measure is inspired by the Fano factor, which we generalize by considering the time-weighted influence of the events given by a shot-noise response function. The sequence of events is assumed to be an equilibrium renewal process, and based on this assumption we present formulas describing the behavior of the variability measure. The formulas are derived for a general response function, restricted only by some natural conditions, but the main focus is given to the shot noise with exponential decrease. The proposed measure is analyzed and compared with the Fano factor. PMID:26651674

  10. Unsolved Mystery of Ball Lightning

    NASA Astrophysics Data System (ADS)

    Bychkov, V. L.

    Ball lightning is an unusual phenomenon always drawing attention of people. There are still questions about its origination, features, interaction with environment, and phenomena related to it. On a way of studying this phenomenon, there are a lot of difficulties, the basic of them is insufficiency of authentic, scientific data. The chapter sets as the purpose to interest the reader in the problem, to describe conditions of ball lightning occurrence, theories, and its hypotheses explanation, to include readers in a circle of experimental searches in creation of a ball lightning and its analogues, and to describe fascination of a problem and difficulty of its solution.

  11. 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…

  12. Ball Aerospace AMSD Progress Update

    NASA Technical Reports Server (NTRS)

    Blair, Mark; Brown, Robert; Chaney, David; Lightsey, Paul; Russell, J. Kevin (Technical Monitor)

    2002-01-01

    The current status of the Advanced Mirror System Demonstrator program being performed by Ball Aerospace is presented. The hexagonal low-areal density Beryllium mirror blank has been fabricated and undergoing polishing at the time of this presentation.

  13. History of ball bearings

    NASA Technical Reports Server (NTRS)

    Dowson, D.; Hamrock, B. J.

    1981-01-01

    The familiar precision rolling-element bearings of the twentieth century are products of exacting technology and sophisticated science. Their very effectiveness and basic simplicity of form may discourage further interest in their history and development. Yet the full story covers a large portion of recorded history and surprising evidence of an early recognition of the advantages of rolling motion over sliding action and progress toward the development of rolling-element bearings. The development of rolling-element bearings is followed from the earliest civilizations to the end of the eighteenth century. The influence of general technological developments, particularly those concerned with the movement of large building blocks, road transportation, instruments, water-raising equipment, and windmills are discussed, together with the emergence of studies of the nature of rolling friction and the impact of economic factors. By 1800 the essential features of ball and rolling-element bearings had emerged and it only remained for precision manufacture and mass production to confirm the value of these fascinating machine elements.

  14. With Flu Shot, Timing May Be Everything

    MedlinePlus

    ... nih.gov/medlineplus/news/fullstory_158514.html With Flu Shot, Timing May Be Everything Vaccination seems to ... 26, 2016 TUESDAY, April 26, 2016 (HealthDay News) -- Flu shots may be more effective when people get ...

  15. Should I Get a Flu Shot?

    MedlinePlus

    ... Text Size Should People With Cancer Get a Flu Shot? Getting a flu shot is recommended for ... need for the flu season. What types of flu vaccines are recommended for people with cancer? People ...

  16. Flu Shot Might Cut Stillbirth Risk

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_158080.html Flu Shot Might Cut Stillbirth Risk Australian researchers find ... THURSDAY, March 31, 2016 (HealthDay News) -- A seasonal flu shot may reduce a pregnant woman's risk of ...

  17. With Flu Shot, Timing May Be Everything

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_158514.html With Flu Shot, Timing May Be Everything Vaccination seems to ... 26, 2016 TUESDAY, April 26, 2016 (HealthDay News) -- Flu shots may be more effective when people get ...

  18. Ball-joint grounding ring

    NASA Technical Reports Server (NTRS)

    Aperlo, P. J. A.; Buck, P. A.; Weldon, V. A.

    1981-01-01

    In ball and socket joint where electrical insulator such as polytetrafluoroethylene is used as line to minimize friction, good electrical contact across joint may be needed for lightning protection or to prevent static-charge build-up. Electrical contact is maintained by ring of spring-loaded fingers mounted in socket. It may be useful in industry for cranes, trailers, and other applications requiring ball and socket joint.

  19. MODIFIED BALL AND SOCKET COUPLING

    DOEpatents

    Kalen, D.D.

    1961-05-23

    A ball and socket coupling arrangement is described in which the male and female members may be engaged or disengaged without visual aid. The female member has an internal spherical seat through which slots are provided to accommodate appropriately arranged and shaped ribs in the ball member. After engagement of the members, one or both are rotated to lock them together to prevent accidental disengagement. (AEC)

  20. Modified Ball and Socket Coupling

    DOEpatents

    Conley, Jr, W. R.; Pitman, R. W.

    1961-05-23

    A ball and socket coupling arrangement is given in which the male and female members may be engaged or disengaged without visual aid. The female member has an internal spherical seat through which slots are provided to accommodate appropriately arranged and shaped ribs in the male ball member. After engagement of the members, one or both are rotated to lock them together to prevent accidental disengagement.

  1. Shot Automation for the National Ignition Facility

    SciTech Connect

    Lagin, L J; Bettenhausen, R C; Beeler, R G; Bowers, G A; Carey, R; Casavant, D D; Cline, B D; Demaret, R D; Domyancic, D M; Elko, S D; Fisher, J M; Hermann, M R; Krammen, J E; Kohut, T R; Marshall, C D; Mathisen, D G; Ludwigsen, A P; Patterson, Jr., R W; Sanchez, R J; Stout, E A; Van Arsdall, P J; Van Wonterghem, B M

    2005-09-21

    A shot automation framework has been developed and deployed during the past year to automate shots performed on the National Ignition Facility (NIF) using the Integrated Computer Control System This framework automates a 4-8 hour shot sequence, that includes inputting shot goals from a physics model, set up of the laser and diagnostics, automatic alignment of laser beams and verification of status. This sequence consists of set of preparatory verification shots, leading to amplified system shots using a 4-minute countdown, triggering during the last 2 seconds using a high-precision timing system, followed by post-shot analysis and archiving. The framework provides for a flexible, model-based execution driven of scriptable automation called macro steps. The framework is driven by high-level shot director software that provides a restricted set of shot life cycle state transitions to 25 collaboration supervisors that automate 8-laser beams (bundles) and a common set of shared resources. Each collaboration supervisor commands approximately 10 subsystem shot supervisors that perform automated control and status verification. Collaboration supervisors translate shot life cycle state commands from the shot director into sequences of ''macro steps'' to be distributed to each of its shot supervisors. Each Shot supervisor maintains order of macro steps for each subsystem and supports collaboration between macro steps. They also manage failure, restarts and rejoining into the shot cycle (if necessary) and manage auto/manual macro step execution and collaborations between other collaboration supervisors. Shot supervisors execute macro step shot functions commanded by collaboration supervisors. Each macro step has database-driven verification phases and a scripted perform phase. This provides for a highly flexible methodology for performing a variety of NIF shot types. Database tables define the order of work and dependencies (workflow) of macro steps to be performed for a

  2. Toxicity of experimental lead-iron shot versus commercial lead shot in mallards

    USGS Publications Warehouse

    Finley, M.T.; Dieter, M.P.

    1978-01-01

    The toxicity of an experimental lead-iron shot containing 38.1 percent lead was compared with commercial lead shot in mallard ducks (Anas platyrhynchos) fed corn for 14 weeks. Significantly higher mortality occurred in ducks dosed with commercial lead shot compared to ducks given lead-iron shot containing comparable amounts of lead. Loss of body weight was indicative of the difference in toxicity of the 2 types of shot. Mortality was dose related in ducks given commercial lead shot; one # 8 shot (73 mg lead) caused 35 percent mortality with higher amounts of lead causing 80 to 100 percent mortality. Ingestion of up to 2 #4 lead-iron shot (111 mg lead) caused no significant weight loss and only 5 percent mortality. However, ducks dosed with 5 lead-iron shot suffered 45 percent mortality and those given 16 shot 50 percent mortality.

  3. Rotary peening with captive shot

    SciTech Connect

    1998-02-01

    Roto Peen with captive shot removes coatings and surface contamination from concrete floors. The objective of treating radioactively contaminated concrete floors during the Deactivation and Decommissioning (D and D) process is to reduce the surface contamination levels to meet regulatory criteria for unrestricted use. The US Department of Energy (DOE) Chicago Operations office and DOE`s Federal Energy Technology Center (FETC) jointly sponsored a Large-Scale Demonstration Project (LSDP) at the Chicago Pile-5 Research Reactor (CP-5) at Argonne National Laboratory-East (ANL). The objective of the LSDP is to demonstrate potentially beneficial D and D technologies in comparison with current baseline technologies. As part of the LSDP, roto Peen with captive shot was demonstrated March 17--20, 1997, to treat a 20 x 25 ft area of radioactively contaminated concrete floor on the service level of the CP-5 building.

  4. 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.)

  5. SnapShot: Multiple Myeloma.

    PubMed

    Braggio, Esteban; Kortüm, K Martin; Stewart, A Keith

    2015-11-01

    Multiple myeloma (MM) is a plasma cell malignancy characterized by a heterogeneous clinical presentation. Genetic abnormalities are not only key events in the origin and progression of the disease but are also useful tools for prognosis, risk stratification, and therapeutic decision making. Although still incurable, a revolution in the treatment of MM is currently ongoing, leading to a significant improvement of clinical outcome and survival. To view this SnapShot, open or download the PDF. PMID:26555176

  6. Incidence of lead shot in canvasbacks

    USGS Publications Warehouse

    Perry, M.C.

    1976-01-01

    During 1975 and 1976, 2,544 canvasbacks (Aythya valisineria) from North Dakota, Wisconsin, Illinois, and Maryland were flouroscoped to determine the incidence of body shot. A significant increase from west to east was detected in the incidence of shot for immatures from the four states. The incidence of shot in immatures after the 1975-76 hunting season was 18 percent in Maryland and 20 percent in Illinois. In Wisconsin no difference in the incidence of shot could be detected between areas trapped or time periods when trapping was conducted. In Maryland a significant decrease in the incidence of body shot was detected in adults, but not immatures, between 1975 and 1976. shot was located throughout the body of canvasbacks. Frequency varied from one to nine shot per bird and averaged 2.0 for adults and 1.5 for immatures.

  7. Electronic hidden solder joint geometry characterization

    NASA Astrophysics Data System (ADS)

    Hsieh, Sheng-Jen

    2009-05-01

    To reduce the size of electronic equipment, multi-layer printed circuit board structures have become popular in recent years. As a result, the inspection of hidden solder joints between layers of boards has become increasingly difficult. Xray machines have been used for ball grid array (BGA) and hidden solder joint inspection; however, the equipment is costly and the inspection process is time consuming. In this paper, we investigate an active thermography approach to probing solder joint geometry. A set of boards having the same number of solder joints and amount of solder paste (0.061 g) was fabricated. Each solder joint had a different geometry. A semi-automated system was built to heat and then transfer each board to a chamber where an infrared camera was used to scan the board as it was cooling down. Two-thirds of the data set was used for model development and one-third was used for model evaluation. Both artificial neural network (ANN) and binary logistic regression models were constructed. Results suggest that solder joints with more surface area cool much faster than those with less surface area. In addition, both modeling approaches are consistent in predicting solder geometry; ANN had 85% accuracy and the regression model had 80%. This approach can potentially be used to test for cold solder joints prior to BGA assembly, since cold solder joints may have air gaps between the joint and the board and air is a poor heat conductor. Therefore, a cold solder joint may have a slower cooling rate than a normal one.

  8. Electromyographic Patterns during Golf Swing: Activation Sequence Profiling and Prediction of Shot Effectiveness.

    PubMed

    Verikas, Antanas; Vaiciukynas, Evaldas; Gelzinis, Adas; Parker, James; Olsson, M Charlotte

    2016-01-01

    This study analyzes muscle activity, recorded in an eight-channel electromyographic (EMG) signal stream, during the golf swing using a 7-iron club and exploits information extracted from EMG dynamics to predict the success of the resulting shot. Muscles of the arm and shoulder on both the left and right sides, namely flexor carpi radialis, extensor digitorum communis, rhomboideus and trapezius, are considered for 15 golf players (∼5 shots each). The method using Gaussian filtering is outlined for EMG onset time estimation in each channel and activation sequence profiling. Shots of each player revealed a persistent pattern of muscle activation. Profiles were plotted and insights with respect to player effectiveness were provided. Inspection of EMG dynamics revealed a pair of highest peaks in each channel as the hallmark of golf swing, and a custom application of peak detection for automatic extraction of swing segment was introduced. Various EMG features, encompassing 22 feature sets, were constructed. Feature sets were used individually and also in decision-level fusion for the prediction of shot effectiveness. The prediction of the target attribute, such as club head speed or ball carry distance, was investigated using random forest as the learner in detection and regression tasks. Detection evaluates the personal effectiveness of a shot with respect to the player-specific average, whereas regression estimates the value of target attribute, using EMG features as predictors. Fusion after decision optimization provided the best results: the equal error rate in detection was 24.3% for the speed and 31.7% for the distance; the mean absolute percentage error in regression was 3.2% for the speed and 6.4% for the distance. Proposed EMG feature sets were found to be useful, especially when used in combination. Rankings of feature sets indicated statistics for muscle activity in both the left and right body sides, correlation-based analysis of EMG dynamics and features

  9. Electromyographic Patterns during Golf Swing: Activation Sequence Profiling and Prediction of Shot Effectiveness

    PubMed Central

    Verikas, Antanas; Vaiciukynas, Evaldas; Gelzinis, Adas; Parker, James; Olsson, M. Charlotte

    2016-01-01

    This study analyzes muscle activity, recorded in an eight-channel electromyographic (EMG) signal stream, during the golf swing using a 7-iron club and exploits information extracted from EMG dynamics to predict the success of the resulting shot. Muscles of the arm and shoulder on both the left and right sides, namely flexor carpi radialis, extensor digitorum communis, rhomboideus and trapezius, are considered for 15 golf players (∼5 shots each). The method using Gaussian filtering is outlined for EMG onset time estimation in each channel and activation sequence profiling. Shots of each player revealed a persistent pattern of muscle activation. Profiles were plotted and insights with respect to player effectiveness were provided. Inspection of EMG dynamics revealed a pair of highest peaks in each channel as the hallmark of golf swing, and a custom application of peak detection for automatic extraction of swing segment was introduced. Various EMG features, encompassing 22 feature sets, were constructed. Feature sets were used individually and also in decision-level fusion for the prediction of shot effectiveness. The prediction of the target attribute, such as club head speed or ball carry distance, was investigated using random forest as the learner in detection and regression tasks. Detection evaluates the personal effectiveness of a shot with respect to the player-specific average, whereas regression estimates the value of target attribute, using EMG features as predictors. Fusion after decision optimization provided the best results: the equal error rate in detection was 24.3% for the speed and 31.7% for the distance; the mean absolute percentage error in regression was 3.2% for the speed and 6.4% for the distance. Proposed EMG feature sets were found to be useful, especially when used in combination. Rankings of feature sets indicated statistics for muscle activity in both the left and right body sides, correlation-based analysis of EMG dynamics and features

  10. MIPP Plastic Ball electronics upgrade

    SciTech Connect

    Baldin, Boris; /Fermilab

    2009-01-01

    An upgrade electronics design for Plastic Ball detector is described. The Plastic Ball detector was a part of several experiments in the past and its back portion (proposed to be used in MIPP) consists of 340 photomultipliers equipped with a sandwich scintillator. The scintillator sandwich has fast and slow signal component with decay times 10 ns and 1 {micro}s respectively. The upgraded MIPP experiment will collect up to 12,000 events during each 4 second spill and read them out in {approx}50 seconds between spills. The MIPP data acquisition system will employ deadtime-less concept successfully implemented in Muon Electronics of Dzero experiment at Fermilab. An 8-channel prototype design of the Plastic Ball Front End (PBFE) implementing these requirements is discussed. Details of the schematic design, simulation and prototype test results are discussed.

  11. How balls roll off tables

    NASA Astrophysics Data System (ADS)

    Bacon, M. E.

    2005-08-01

    The motion of a ball rolling off the edge of a table is studied theoretically and experimentally. A detailed analysis of the motion requires consideration of an initial no-slip phase followed by a brief slipping phase. To obtain quantitative predictions for comparison with experiment, the equations were solved numerically. Data are obtained using video recordings, and the experimentally determined angular velocity before and after the ball leaves the table is compared with the theoretical calculations. The inadequacy of a previous analysis is demonstrated. Suggestions for other experiments are made.

  12. Ball lightning risk to aircraft

    NASA Astrophysics Data System (ADS)

    Doe, R.; Keul, A.

    2009-04-01

    Lightning is a rare but regular phenomenon for air traffic. Aircraft are designed to withstand lightning strikes. Research on lightning and aircraft can be called detailed and effective. In the last 57 years, 18 reported lightning aviation disasters with a fatality figure of at least 714 persons occurred. For comparison, the last JACDEC ten-year average fatality figure was 857. The majority encountered lightning in the climb, descent, approach and/or landing phase. Ball lightning, a metastable, rare lightning type, is also seen from and even within aircraft, but former research only reported individual incidents and did not generate a more detailed picture to ascertain whether it constitutes a significant threat to passenger and aircraft safety. Lacking established incident report channels, observations were often only passed on as "air-travel lore". In an effort to change this unsatisfactory condition, the authors have collected a first international dataset of 38 documented ball lightning aircraft incidents from 1938 to 2001 involving 13 reports over Europe, 13 over USA/Canada, and 7 over Russia. 18 (47%) reported ball lightning outside the aircraft, 18 (47%) inside, 2 cases lacked data. 8 objects caused minor damage, 8 major damage (total: 42%), only one a crash. No damage was reported in 18 cases. 3 objects caused minor crew injury. In most cases, ball lightning lasted several seconds. 11 (29%) incidents ended with an explosion of the object. A cloud-aircraft lightning flash was seen in only 9 cases (24%) of the data set. From the detailed accounts of air personnel in the last 70 years, it is evident that ball lightning is rarely, but consistently observed in connection with aircraft and can also occur inside the airframe. Reports often came from multiple professional witnesses and in several cases, damages were investigated by civil or military authorities. Although ball lightning is no main air traffic risk, the authors suggest that incident and accident

  13. Semantic Shot Classification in Sports Video

    NASA Astrophysics Data System (ADS)

    Duan, Ling-Yu; Xu, Min; Tian, Qi

    2003-01-01

    In this paper, we present a unified framework for semantic shot classification in sports videos. Unlike previous approaches, which focus on clustering by aggregating shots with similar low-level features, the proposed scheme makes use of domain knowledge of a specific sport to perform a top-down video shot classification, including identification of video shot classes for each sport, and supervised learning and classification of the given sports video with low-level and middle-level features extracted from the sports video. It is observed that for each sport we can predefine a small number of semantic shot classes, about 5~10, which covers 90~95% of sports broadcasting video. With the supervised learning method, we can map the low-level features to middle-level semantic video shot attributes such as dominant object motion (a player), camera motion patterns, and court shape, etc. On the basis of the appropriate fusion of those middle-level shot classes, we classify video shots into the predefined video shot classes, each of which has a clear semantic meaning. The proposed method has been tested over 4 types of sports videos: tennis, basketball, volleyball and soccer. Good classification accuracy of 85~95% has been achieved. With correctly classified sports video shots, further structural and temporal analysis, such as event detection, video skimming, table of content, etc, will be greatly facilitated.

  14. Ball Possession Effectiveness in Men’s Elite Floorball According to Quality of Opposition and Game Period

    PubMed Central

    Gómez, Miguel-Ángel; Prieto, Miguel; Pérez, Javier; Sampaio, Jaime

    2013-01-01

    The aim of the present study was to identify the importance of floorball tactical variables to predict ball possession effectiveness, when controlling quality of opposition and game periods. The sample was composed by 1500 ball possessions, corresponding to 14 games randomly selected from the International Championships played during 2008 and 2010 (World Championship, Four nations tournament and classificatory phases for World Championship) by teams from different competition levels (HIGH, INTERMEDIATE and LOW). The effects of the predictor variables on successful ball possessions according to the three game contexts (HIGH vs. HIGH; HIGH vs. LOW; LOW vs. LOW games) were analyzed using Binomial Logistic Regressions. The results showed no interaction with the game period. In HIGH vs. HIGH games, quality of opposition showed an association with ball possession effectiveness with ending zone, offensive system, possession duration, height of shooting and defensive pressures previous to the shot. In HIGH vs. LOW games the important factors were the starting zone, possession duration, defensive pressure previous to the last pass and to the shot, technique of shooting and the number players involved in each ball possession. Finally, in LOW vs. LOW games, the results emphasized the importance of starting and ending zones, the number of passes used and the technique of shooting. In conclusion, elite floorball performance is mainly affected by quality of opposition showing different game patterns in each context that should be considered by coaches when preparing practices and competitions. PMID:24235997

  15. Temporal structure analysis of broadcast tennis video using hidden Markov models

    NASA Astrophysics Data System (ADS)

    Kijak, Ewa; Oisel, Lionel; Gros, Patrick

    2003-01-01

    This work aims at recovering the temporal structure of a broadcast tennis video from an analysis of the raw footage. Our method relies on a statistical model of the interleaving of shots, in order to group shots into predefined classes representing structural elements of a tennis video. This stochastic modeling is performed in the global framework of Hidden Markov Models (HMMs). The fundamental units are shots and transitions. In a first step, colors and motion attributes of segmented shots are used to map shots into 2 classes: game (view of the full tennis court) and not game (medium, close up views, and commercials). In a second step, a trained HMM is used to analyze the temporal interleaving of shots. This analysis results in the identification of more complex structures, such as first missed services, short rallies that could be aces or services, long rallies, breaks that are significant of the end of a game and replays that highlight interesting points. These higher-level unit structures can be used either to create summaries, or to allow non-linear browsing of the video.

  16. Aligner for Elastic Collisions of Dropped Balls.

    ERIC Educational Resources Information Center

    Mellen, Walter Roy

    1995-01-01

    Discusses an aligner that permits dropping a stack of any number of balls of different sizes, elasticities, hardnesses, or types to observe the rebound of the top ball. Experimental results allow a reasonable comparison with theory. (MVL)

  17. Hidden attractors in dynamical systems

    NASA Astrophysics Data System (ADS)

    Dudkowski, Dawid; Jafari, Sajad; Kapitaniak, Tomasz; Kuznetsov, Nikolay V.; Leonov, Gennady A.; Prasad, Awadhesh

    2016-06-01

    Complex dynamical systems, ranging from the climate, ecosystems to financial markets and engineering applications typically have many coexisting attractors. This property of the system is called multistability. The final state, i.e., the attractor on which the multistable system evolves strongly depends on the initial conditions. Additionally, such systems are very sensitive towards noise and system parameters so a sudden shift to a contrasting regime may occur. To understand the dynamics of these systems one has to identify all possible attractors and their basins of attraction. Recently, it has been shown that multistability is connected with the occurrence of unpredictable attractors which have been called hidden attractors. The basins of attraction of the hidden attractors do not touch unstable fixed points (if exists) and are located far away from such points. Numerical localization of the hidden attractors is not straightforward since there are no transient processes leading to them from the neighborhoods of unstable fixed points and one has to use the special analytical-numerical procedures. From the viewpoint of applications, the identification of hidden attractors is the major issue. The knowledge about the emergence and properties of hidden attractors can increase the likelihood that the system will remain on the most desirable attractor and reduce the risk of the sudden jump to undesired behavior. We review the most representative examples of hidden attractors, discuss their theoretical properties and experimental observations. We also describe numerical methods which allow identification of the hidden attractors.

  18. No need for a social cue! A masked magician can also trick the audience in the vanishing ball illusion.

    PubMed

    Thomas, Cyril; Didierjean, André

    2016-01-01

    In the vanishing ball illusion (VBI), a magician throws a ball up in the air twice, after which he pretends to toss it up again, when in fact it remains secretly concealed in his hand. Observers perceive an imaginary ball disappearing into the air. According to Kuhn and Land (2006), the VBI during the fake throw is mediated by the magician's gaze and/or head direction (also called "social cues") as he looks toward the imaginary ball. The aim of this article is to test an alternative interpretation. According to our hypothesis, the magician's social cues are not essential to the VBI. We compared the numbers of participants experiencing the VBI when the magician's social cues were directed toward the illusory ball and when the magician's social cues were either hidden behind a black mask (Exp. 1) or stationary (Exp. 2). The results showed that the number of observers experiencing the VBI was high (almost two-thirds of the participants), regardless of whether the magician's social cueing was directed toward the illusion, hidden behind a mask, or stationary. In a third experiment (Exp. 3), we replicated Kuhn and Land's initial results and attempted to further explain their "anti-illusion" social-cue effect. This study confirms that social cueing is not required in the VBI: Its presence did not increase the number of participants experiencing the illusion. PMID:26676869

  19. Vertical bounce of two vertically aligned balls

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2007-11-01

    When a tennis ball rests on top of a basketball and both drop to the floor together, the tennis ball is projected vertically at high speed. A mass-spring model of the impact, as well as air track data, suggest that the tennis ball should be projected at relatively low speed. Measurements of the forces on each ball and the bounce of vertically aligned superballs are used to resolve the discrepancy.

  20. 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.

  1. Does Ease to Block a Ball Affect Perceived Ball Speed? Examination of Alternative Hypotheses

    ERIC Educational Resources Information Center

    Witt, Jessica K.; Sugovic, Mila

    2012-01-01

    According to an action-specific account of perception, the perceived speed of a ball can be a function of the ease to block the ball. Balls that are easier to stop look like they are moving slower than balls that are more difficult to stop. This was recently demonstrated with a modified version of the classic computer game Pong (Witt & Sugovic,…

  2. Shot noise in ballistic graphene.

    PubMed

    Danneau, R; Wu, F; Craciun, M F; Russo, S; Tomi, M Y; Salmilehto, J; Morpurgo, A F; Hakonen, P J

    2008-05-16

    We have investigated shot noise in graphene field effect devices in the temperature range of 4.2-30 K at low frequency (f=600-850 MHz). We find that for our graphene samples with a large width over length ratio W/L, the Fano factor F reaches a maximum F ~ 1/3 at the Dirac point and that it decreases strongly with increasing charge density. For smaller W/L, the Fano factor at Dirac point is significantly lower. Our results are in good agreement with the theory describing that transport at the Dirac point in clean graphene arises from evanescent electronic states. PMID:18518472

  3. Secrets of the Crystal Ball

    ERIC Educational Resources Information Center

    Croucher, John S.

    2007-01-01

    This article describes how a crystal ball known as "The Flash Mind Reader" is played. "The Flash Mind Reader" is a mathematics game in which the player is invited to select any-two digit number and then subtract the sum of these two digits from the original number. A chart is provided in which the (adjusted) number they obtained will have a symbol…

  4. Idea Bank: Wiffle Ball Physics

    ERIC Educational Resources Information Center

    Lancor, Rachael

    2009-01-01

    Projectile motion, a cornerstone topic of introductory physics, is usually a student's first exposure to the problem-solving techniques used in this subject. Often, this is an inactive learning experience--students work with pencil and paper to read and solve projectile motion problems (e.g., diagrams and descriptions of balls being hit, kicked,…

  5. Laboratory-produced ball lightning

    NASA Astrophysics Data System (ADS)

    Golka, Robert K., Jr.

    1994-05-01

    For 25 years I have actively been searching for the true nature of ball lightning and attempting to reproduce it at will in the laboratory. As one might expect, many unidentified lights in the atmosphere have been called ball lightning, including Texas Maffa lights (automobile headlights), flying saucers (UFOs), swamp gas in Ann Arbor, Michigan, etc. For 15 years I thought ball lightning was strictly a high-voltage phenomenon. It was not until 1984 when I was short-circuiting the electrical output of a diesel electric railroad locomotive that I realized that the phenomenon was related more to a high current. Although I am hoping for some other types of ball lightning to emerge such as strictly electrostatic-electromagnetic manifestations, I have been unlucky in finding laboratory provable evidence. Cavity-formed plasmodes can be made by putting a 2-inch burning candle in a home kitchen microwave oven. The plasmodes float around for as long as the microwave energy is present.

  6. Ball Aerospace Actuator Cryogenic Testing

    NASA Technical Reports Server (NTRS)

    Kingsbury, Lana; Lightsey, Paul; Quigley, Phil; Rutkowski, Joel; Russell, J. Kevin (Technical Monitor)

    2002-01-01

    The ambient testing characterizing step size and repeatability for the Ball Aerospace Cryogenic Nano-Positioner actuators for the AMSD (Advanced Mirror System Demonstrator) program has been completed and are presented. Current cryogenic testing is underway. Earlier cryogenic test results for a pre-cursor engineering model are presented.

  7. 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.

  8. A biomechanical comparison of the topspin and backspin forehand approach shots in tennis.

    PubMed

    Elliott, B; Marsh, T

    1989-01-01

    Three-dimensional (3-D) high-speed cinematographic techniques were used to record topspin and backspin forehand approach shots hit down-the-line by high-performance players. The direct linear transformation (DLT) technique was used in the 3-D space reconstruction from 2-D images recorded via laterally placed phase-locked cameras operating at 200 Hz. A Mann-Whitney U-test was calculated for the different aspects of the topspin and backspin shots to test for significance (P less than 0.05). A significant difference was recorded between topspin and backspin shots in the angle of the racket at the completion of the backswing. The racket was taken 0.48 rad past a line drawn perpendicular to the back fence for topspin trials, but only rotated 0.86 rad from a line parallel to the net in the backspin shot. Maximum racket velocities occurred prior to impact and were significantly higher in topspin (26.5 m s-1) compared to backspin (16.6 m s-1) trials. This resulted in the topspin trials recording a significantly higher ball velocity compared to backspin trials (27.6 m s-1 vs 21.7 m s-1). Pre-impact racket trajectories revealed that in topspin shots the racket moved on an upward path of 0.48 rad while in backspin shots it moved down at an angle of 0.34 rad. In the topspin trials impact occurred significantly further forward of the front foot than in backspin shots (0.26 m vs 0.05 m) while the angle of the racket was the same for both strokes (0.14 rad behind a line parallel to the net). The mean angle of the racket-face at impact was inclined backwards by 0.11 rad for backspin strokes and rotated forward by 0.13 rad for topspin strokes. Angles of incidence and reflection of the impact between the ball and the court showed that backspin trials had larger angles of incidence and reflection than topspin strokes. PMID:2621759

  9. Aerodynamics of a golf ball with grooves

    NASA Astrophysics Data System (ADS)

    Kim, Jooha; Son, Kwangmin; Choi, Haecheon

    2009-11-01

    It is well known that the drag on a dimpled ball is much lower than that on smooth ball. Choi et al. (Phys. Fluids, 2006) showed that turbulence is generated through the instability of shear layer separating from the edge of dimples and delays flow separation. Based on this mechanism, we devise a new golf ball with grooves on the surface but without any dimples. To investigate the aerodynamic performance of this new golf ball, an experiment is conducted in a wind tunnel at the Reynolds numbers of 0.5 x10^5 - 2.7 x10^5 and the spin ratios (ratio of surface velocity to the free-stream velocity) of α=0 - 0.5, which are within the ranges of real golf-ball velocity and spin rate. We measure the drag and lift forces on the grooved ball and compare them with those of smooth ball. At zero spin, the drag coefficient on the grooved ball shows a rapid fall-off at a critical Reynolds number and maintains a minimum value which is lower by 50% than that on smooth ball. At non-zero α, the drag coefficient on the grooved ball increases with increasing α, but is still lower by 40% than that on smooth ball. The lift coefficient on the grooved ball increases with increasing α, and is 100% larger than that on smooth ball. The aerodynamic characteristics of grooved ball is in general quite similar to that of dimpled ball. Some more details will be discussed in the presentation.

  10. Hidden Magnetic Portals Around Earth

    NASA Video Gallery

    A NASA-sponsored researcher at the University of Iowa has developed a way for spacecraft to hunt down hidden magnetic portals in the vicinity of Earth. These gateways link the magnetic field of our...

  11. Ethics, Equity, and Hidden Privilege.

    ERIC Educational Resources Information Center

    Lawler, Patricia A.

    1996-01-01

    Issues of race and gender are often overlooked in ethical dilemmas. Adult educators must be aware of core professional values, thoughtfully analyze their biases, and acknowledge hidden privileges. (JOW)

  12. Child Abuse: The Hidden Bruises

    MedlinePlus

    ... AACAP Facts for Families Guide Skip breadcrumb navigation Child Abuse - The Hidden Bruises Quick Links Facts For Families ... 5; Updated November 2014 The statistics on physical child abuse are alarming. It is estimated hundreds of thousands ...

  13. Fate of thermal log type Q balls

    SciTech Connect

    Chiba, Takeshi; Kamada, Kohei; Kasuya, Shinta; Yamaguchi, Masahide

    2010-11-15

    We study time evolution of the Q ball in thermal logarithmic potential using lattice simulations. As the temperature decreases due to the cosmic expansion, the thermal logarithmic term in the potential is eventually overcome by a mass term, and we confirm that the Q ball transforms from the thick-wall type to the thin-wall type for a positive coefficient of radiative corrections to the mass term, as recently suggested. Moreover, we find that the Q ball finally ''melts down'' when the Q-ball solution disappears. We also discuss the effects of this phenomenon on the detectability of gravitational waves from the Q-ball formation.

  14. Hidden Statistics of Schroedinger Equation

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2011-01-01

    Work was carried out in determination of the mathematical origin of randomness in quantum mechanics and creating a hidden statistics of Schr dinger equation; i.e., to expose the transitional stochastic process as a "bridge" to the quantum world. The governing equations of hidden statistics would preserve such properties of quantum physics as superposition, entanglement, and direct-product decomposability while allowing one to measure its state variables using classical methods.

  15. [The danger of the game called "paint ball"].

    PubMed

    Gazagne, C; Larricart, P; Haut, J

    1994-04-01

    Severe ocular injuries may occur during a new war game in France, called "paint ball". A high pressure carbon dioxide powered gun fires pellets filled with dye. The pellet is coated with a semisoft gelatin and filled with a "nontoxic" dye mixture. We observed six consecutive cases during a ten month-period. In two cases (both due to a shot at point-blank range), mature cataract occurred. Consequently, lensectomy was achieved, preceded by a prophylactic scleral buckle. In one case, a retinal detachment due to a localized retinal necrosis occurred. With endocular surgery and temporary silicone oil tamponade, we achieved retinal reattachment. The three remaining cases did not require surgery. They suffered blunt ocular lesions of the anterior and/or posterior segment. One of these cases showed permanent tattooing to the cornea. After a mean follow-up lasting six months, all patients had, at least, a 40/100 vision. Some recommendations can reduce the incidence and the severity of ocular injuries due to paint balling. Firstly, eyeguards (made of polycarbonate) must be worn before receiving guns and pellets. Secondly, a kind of safety gun stopper can avoid gun firing by accident apart from practices. Thirdly, according to others publications, alcohol or drugs should not be consumed before the game. Lastly, gun fire at point-blank range or toward the head must be forbidden. We hope that wide distribution of such recommendations will help reducing the frequency of this type of ocular traumas. PMID:8076200

  16. Hidden asymmetry of ice.

    PubMed

    Kirov, Mikhail V

    2014-11-26

    Ice is a very complex and fundamentally important solid. In the present article, we review a new property of the hydrogen-bonded network in ice structures: an explicit nonequivalence of some antipodal configurations with the opposite direction of all hydrogen bonds (H-bonds). This asymmetry is most pronounced for the structures with considerable deviation of the H-bond network from the tetrahedral coordination. That is why we have investigated in detail four-coordinated ice nanostructures with no outer "dangling" hydrogen atoms, namely, ice bilayers and ice nanotubes consisting of stacked n-membered rings. The reason for this H-bonding asymmetry is a fundamental nonequivalence of the arrangements of water molecules in some antipodal configurations with the opposite direction of all H-bonds. For these configurations, the overall pictures of deviations of the hydrogen bonds from linearity are qualitatively different. We consider the reversal of all H-bonds as an additional nongeometric operation of symmetry, more precisely antisymmetry. It is not easy to find the explicit breaking of the symmetry of hydrogen bonding (H-symmetry) in the variety of all configurations. Therefore, this asymmetry may be named hidden. PMID:24905908

  17. Beating the bunker: the effect of PETTLEP imagery on golf bunker shot performance.

    PubMed

    Smith, Dave; Wright, Caroline J; Cantwell, Cara

    2008-09-01

    The aim of this study was to compare the effects of physical practice with PETTLEP-based (Physical, Environment, Task, Timing, Learning, Emotion and Perspective; Holmes & Collins, 2001) imagery and PETTLEP + physical practice interventions on golf bunker shot performance. Thirty-two male county- or international-level golfers were assigned to one of four groups; PETTLEP imagery, physical practice, PETTLEP + physical practice, or control. The PETTLEP imagery group imaged 15 bunker shots, their interventions incorporating PETTLEP components, such as physical, environment, and emotion, twice a week. The physical practice group physically performed their 15 bunker shots twice per week; the PETTLEP + physical practice group performed PETTLEP imagery once per week and physical practice once per week. Each group performed their respective tasks for 6 weeks. Pre- and posttests consisted of 15 bunker shots, with points awarded according to the ball proximity to the pin. All groups improved significantly (p < .01) from pre- to posttest, and the PETTLEP + physical practice group improved more (p < .05) than the PETTLEP and physical practice groups. However, there was no significant difference between the physical practice and PETTLEP groups (p > .05). Findings, therefore, support the effectiveness of PETTLEP in enhancing golf performance, especially when combined with physical practice. PMID:18816950

  18. Effect of Shot Peening on Surface Chracteristics of Carbon Steel with Different Heat Treatments

    NASA Astrophysics Data System (ADS)

    Harada, Yasunori; Yakura, Ryota

    2011-01-01

    The shot peening process is one of the surface treatments. The peening effects are characterized by the fact that the surface layer undergoes large plastic deformation due to the collision of shots. This action imparts compressive residual stress on the surface, thus improving the fatigue life of the component. Therefore, this process has been utilized in order to improve the performance of engineering components. Researchers have been found a number of new phenomena in the shot peening process. It is well known that the peening effects are greatly influenced by the processing history or the thermal history of material. The hardness near the surface of the deformed material or heat treated material was often decreased by shot peening. Presently, little is known about the relation between hardness of the shot peened surface and the processing history of materials. In the present study, the effects of shot peening conditions on the surface characteristics of medium carbon steels with different heat treatments were investigated. In the experiment, the shot peening process was performed with an air-type machine using cast steel balls. Air pressure is in the range from 0.4 to 0.8 MPa and coverage is from 200 to 2000%. The workpiece was used the commercial medium carbon steel JIS-S45C. These are annealed at 900° C for 7.2 ks and quenched and tempered from 850° C in oil. Hardness, surface roughness, and compressive residual stress in the peened workpieces were measured. When the tempered workpiece was shot peened, the hardness of the surface was considerably lowered. The hardness distribution shows work softening near the surface. This amount increases with increasing coverage. This is due to the influence of processing heat generated by the plastic deformation during shot peening. The maximum residual stress appears about 840 MPa at about 0.180 mm in depth from the surface. It was found that the difference of the thermal history of the workpiece influences the hardness

  19. Vibrations of Hybrid Ceramic Ball Bearings

    NASA Astrophysics Data System (ADS)

    Ohta, H.; Kobayashi, K.

    1996-05-01

    Hybrid ceramic ball bearings with silicone nitride balls and steel rings were tested, and the vibration characteristics were compared with those of conventional steel ball bearings. In this study, two types of hybrid ceramic ball bearings and two types of conventional steel ball bearings were used as test bearings. The test bearings were operated under several rotational speeds and axial loads. The radial and the axial vibrations on the outer ring of each test bearing were detected by an accelerometer. The vibrations were examined by using an FFT analyzer. From the experimental results, analysis and discussion, the vibration characteristics of hybrid ceramic ball bearings, compared with those of conventional steel ball bearings, are explained.

  20. 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

  1. 7 CFR 51.904 - Shot berries.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Shot berries. 51.904 Section 51.904 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Table Grapes (European or Vinifera Type) 1 Definitions § 51.904 Shot berries....

  2. SunShot Initiative Portfolio Book 2014

    SciTech Connect

    Solar Energy Technologies Office

    2014-05-01

    The 2014 SunShot Initiative Portfolio Book outlines the progress towards the goals outlined in the SunShot Vision Study. Contents include overviews of each of SunShot’s five subprogram areas, as well as a description of every active project in the SunShot’s project portfolio as of May 2014.

  3. SnapShot: Renal Cell Carcinoma.

    PubMed

    Turajlic, Samra; Larkin, James; Swanton, Charles

    2015-12-01

    This SnapShot summarizes current knowledge about the key features in mutational landscape, major pathways, and tumor evolution and heterogeneity in renal cell carcinoma, as well as the most recent advances in therapeutic development. To view this SnapShot, open or download the PDF. PMID:26638079

  4. Polymer-composite ball lightning.

    PubMed

    Bychkov, V L

    2002-01-15

    Investigations into the state of ball lightning (BL) have been made, and both theory and experiments, related to so-called "polymer-composite" ball lightning, are presented. The properties of such a polymeric BL have been described and are that of a long-lived object capable of storing high energy. Results of experiments, starting with polymeric components in erosive gas discharge experiments, are described and discussed. The model of BL as a highly charged polymer-dielectric structure is described. According to this model BL appears as the result of the aggregation of natural polymers, such as lignin and cellulose, soot, polymeric silica and other natural dust particles. Its ability to glow is explained by the appearance over its perimeter of gas discharges near the highly charged BL surface, and electrical breakdown of some regions on the surface, consisting of polymerized and aggregated threads. PMID:16210170

  5. The killing efficiency of soft iron shot

    USGS Publications Warehouse

    Andrews, R.; Longcore, J.R.

    1969-01-01

    A cooperative research effort between the ammunition industry and the Bureau of Sport Fisheries and Wildlife is aimed at finding a suitable non-toxic substitute for lead shot. A contract study by an independent research organization evaluated ways of coating or detoxifying lead shot or replacing it with another metal. As a result of that study, the only promising candidate is soft iron. Previous tests of hard iron shot had suggested that its killing effectiveness was poor at longer ranges due to the lower density. In addition, its hardness caused excessive damage to shotgun barrels. A unique, automated shooting facility was constructed at the Patuxent Wildlife Research Center to test the killing effectiveness of soft iron shot under controlled conditions. Tethered game-farm mallards were transported across a shooting point in a manner simulating free flight. A microswitch triggered a mounted shotgun so that each shot was 'perfect.' A soft iron shot, in Number 4 size, was produced by the ammunition industry and loaded in 12-gauge shells to give optimum ballistic performance. Commercial loads of lead shot in both Number 4 and Number 6 size were used for comparison. A total of 2,010 ducks were shot at ranges of 30 to 65 yards and at broadside and head-on angles in a statistically designed procedure. The following data were recorded for each duck: time until death, broken wing or leg bones, and number of embedded shot. Those ducks not killed outright were held for 10 days. From these data, ducks were categorized as 'probably bagged,' 'probably lost cripples,' or survivors. The test revealed that the killing effectiveness of this soft iron shot was superior to its anticipated performance and close to that obtained with commercial lead loads containing an equal number of pellets. Bagging a duck, in terms of rapid death or broken wing, was primarily dependent on the probability of a shot striking that vital area, and therefore a function of range. There was no indication

  6. Enhanced osteoblast proliferation and corrosion resistance of commercially pure titanium through surface nanostructuring by ultrasonic shot peening and stress relieving.

    PubMed

    Jindal, Shitu; Bansal, Rajesh; Singh, Bijay P; Pandey, Rajiv; Narayanan, Shankar; Wani, Mohan R; Singh, Vakil

    2014-07-01

    This investigation was carried out to study the effect of a novel process of surface modification, surface nanostructuring by ultrasonic shot peening, on osteoblast proliferation and corrosion behavior of commercially pure titanium (c p-Ti) in simulated body fluid. A mechanically polished disc of c p-Ti was subjected to ultrasonic shot peening with stainless steel balls to create nanostructure at the surface. A nanostructure (<20 nm) with inhomogeneous distribution was revealed by atomic force and scanning electron microscopy. There was an increase of approximately 10% in cell proliferation, but there was drastic fall in corrosion resistance. Corrosion rate was increased by 327% in the shot peened condition. In order to examine the role of residual stresses associated with the shot peened surface on these aspects, a part of the shot peened specimen was annealed at 400°C for 1 hour. A marked influence of annealing treatment was observed on surface structure, cell proliferation, and corrosion resistance. Surface nanostructure was much more prominent, with increased number density and sharper grain boundaries; cell proliferation was enhanced to approximately 50% and corrosion rate was reduced by 86.2% and 41% as compared with that of the shot peened and the as received conditions, respectively. The highly significant improvement in cell proliferation, resulting from annealing of the shot peened specimen, was attributed to increased volume fraction of stabilized nanostructure, stress recovery, and crystallization of the oxide film. Increase in corrosion resistance from annealing of shot peened material was related to more effective passivation. Thus, the surface of c p-Ti, modified by this novel process, possessed a unique quality of enhancing cell proliferation as well as the corrosion resistance and could be highly effective in reducing treatment time of patients adopting dental and orthopedic implants of titanium and its alloys. PMID:25020216

  7. Keeping Your Eyes Continuously on the Ball While Running for Catchable and Uncatchable Fly Balls

    PubMed Central

    Postma, Dees B. W.; den Otter, A. Rob; Zaal, Frank T. J. M.

    2014-01-01

    When faced with a fly ball approaching along the sagittal plane, fielders need information for the control of their running to the interception location. This information could be available in the initial part of the ball trajectory, such that the interception location can be predicted from its initial conditions. Alternatively, such predictive information is not available, and running to the interception location involves continuous visual guidance. The latter type of control would predict that fielders keep looking at the approaching ball for most of its flight, whereas the former type of control would fit with looking at the ball during the early part of the ball's flight; keeping the eyes on the ball during the remainder of its trajectory would not be necessary when the interception location can be inferred from the first part of the ball trajectory. The present contribution studied visual tracking of approaching fly balls. Participants were equipped with a mobile eye tracker. They were confronted with tennis balls approaching from about 20 m, and projected in such a way that some balls were catchable and others were not. In all situations, participants almost exclusively tracked the ball with their gaze until just before the catch or until they indicated that a ball was uncatchable. This continuous tracking of the ball, even when running close to their maximum speeds, suggests that participants employed continuous visual control rather than running to an interception location known from looking at the early part of the ball flight. PMID:24670972

  8. Shot-size reduction of photoresist formulations

    NASA Astrophysics Data System (ADS)

    Moreau, Wayne M.; Cornett, Kathleen M.; Fahey, James T.; Linehan, Leo L.; Montgomery, Warren; Plat, Marina V.; Smith, Randolph S.; Wood, Robert L.

    1995-06-01

    The cost of expendable chemicals in the resist process is increasing and with this the economic impetus to conserve usage. The volume of liquid resist dispensed (shot size) determines the consumption rate and disposal volumes of liquid resist. The choice of resist solvent can influence the shot volume. Three formulation factors influence the shot size: (1) the surface tension of the resist and the interfacial energy of the coating surface, (2) the viscosity of the resist formulation, and (3) the evaporation rate of the solvent. The suitable resist formulation and subsequent solvent choice should be of the lowest surface tension and lowest viscosity and be balanced by an evaporation rate which allows a minimum shot volume to be spread on the surface without significant solvent loss. Of all the solvents examined, ethyl 3-ethoxy propionate (EEP) gave the lowest shot size relative to the old resist solvent standard of 2- ethoxy ethyl acetate (ECA).

  9. Billion shot flashlamp for spaceborne lasers

    NASA Technical Reports Server (NTRS)

    Richter, Linda; Schuda, Felix; Degnan, John

    1990-01-01

    A billion-shot flashlamp developed under a NASA contract for spaceborne laser missions is presented. Lifetime-limiting mechanisms are identified and addressed. Two energy loadings of 15 and 44 Joules were selected for the initial accelerated life testing. A fluorescence-efficiency test station was used for measuring the useful-light output degradation of the lamps. The design characteristics meeting NASA specifications are outlined. Attention is focused on the physical properties of tungsten-matrix cathodes, the chemistry of dispenser cathodes, and anode degradation. It is reported that out of the total 83 lamps tested in the program, 4 lamps reached a billion shots and one lamp is beyond 1.7 billion shots, while at 44 Joules, 4 lamps went beyond 100 million shots and one lamp reached 500 million shots.

  10. Ball Aerospace Hybrid Space Cryocoolers

    NASA Astrophysics Data System (ADS)

    Gully, W.; Glaister, D. S.; Hendershott, P.; Kotsubo, V.; Lock, J. S.; Marquardt, E.

    2008-03-01

    This paper describes the design, development, testing, and performance at Ball Aerospace of a long-life hybrid (combination of Stirling and Joule-Thomson [J-T] thermodynamic cycles) space cryocooler. Hybrid coolers are synergistic combinations of two thermodynamic cycles that combine advantages of each cycle to yield overall improved performance. Hybrid cooler performance advantages include: 1) load leveling of large heat loads; 2) remote cryogenic cooling with very low to negligible induced vibration and jitter; 3) very low redundant (off state) cooler penalties; 4) high power efficiency, especially at low temperatures; and 5) simplified system integration with capability to cross gimbals and no need for thermal straps or switches. Ball Aerospace is currently developing several different hybrid cooler systems. The 35 K hybrid cooler provides 2.0 W at 35 K and 8.5 W at 85 K with an emphasis on load leveling of high transient heat loads and remote, low vibration cooling. The 10 K hybrid cooler provides 200 mW at 10 K, 700 mW at 15 K, and 10.7 W at 85 K with an emphasis on power efficiency. In addition, Ball Aerospace built and tested a complete hybrid cooler that met the requirements of the JWST Mid-Infrared Instrument (MIRI) cooler including providing 80 mW at 6 K and 100 mW at 18 K for a total system (28 V) power of 310 W.

  11. Adults Don't Need Tetanus Shot Every Decade

    MedlinePlus

    ... fullstory_157980.html Adults Don't Need Tetanus Shot Every Decade: Study Booster shot every 30 years would protect as well as ... have always been told to get a tetanus shot every 10 years, but actually, there is very ...

  12. 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.

  13. 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

    Evaluation of hot-pressed silicon nitride as a rolling-element bearing material. Two grades of hot-pressed silicon nitride balls were tested under rolling contact conditions in a five-ball fatigue tester. A digital computer program was used to predict the dynamic performance characteristics and fatigue life of high-speed ball bearings with silicon nitride balls relative to that with bearings containing steel balls. The results obtained include the finding that fatigue spalls on silicon nitride balls are similar in appearance to those obtained with typical bearing steels.

  14. 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

  15. Structural dynamic analysis of a ball joint

    NASA Astrophysics Data System (ADS)

    Hwang, Seok-Cheol; Lee, Kwon-Hee

    2012-11-01

    Ball joint is a rotating and swiveling element that is typically installed at the interface between two parts. In an automobile, the ball joint is the component that connects the control arms to the steering knuckle. The ball joint can also be installed in linkage systems for motion control applications. This paper describes the simulation strategy for a ball joint analysis, considering manufacturing process. Its manufacturing process can be divided into plugging and spinning. Then, the interested responses is selected as the stress distribution generated between its ball and bearing. In this paper, a commercial code of NX DAFUL using an implicit integration method is introduced to calculate the response. In addition, the gap analysis is performed to investigate the fitness, focusing on the response of the displacement of a ball stud. Also, the optimum design is suggested through case studies.

  16. 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.

  17. Adiabatic invariance of oscillons/I -balls

    NASA Astrophysics Data System (ADS)

    Kawasaki, Masahiro; Takahashi, Fuminobu; Takeda, Naoyuki

    2015-11-01

    Real scalar fields are known to fragment into spatially localized and long-lived solitons called oscillons or I -balls. We prove the adiabatic invariance of the oscillons/I -balls for a potential that allows periodic motion even in the presence of non-negligible spatial gradient energy. We show that such a potential is uniquely determined to be the quadratic one with a logarithmic correction, for which the oscillons/I -balls are absolutely stable. For slightly different forms of the scalar potential dominated by the quadratic one, the oscillons/I -balls are only quasistable, because the adiabatic charge is only approximately conserved. We check the conservation of the adiabatic charge of the I -balls in numerical simulation by slowly varying the coefficient of logarithmic corrections. This unambiguously shows that the longevity of oscillons/I -balls is due to the adiabatic invariance.

  18. 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.

  19. Basketball shot types and shot success in different levels of competitive basketball.

    PubMed

    Erčulj, Frane; Štrumbelj, Erik

    2015-01-01

    The purpose of our research was to investigate the relative frequencies of different types of basketball shots (above head, hook shot, layup, dunk, tip-in), some details about their technical execution (one-legged, two-legged, drive, cut, …), and shot success in different levels of basketball competitions. We analysed video footage and categorized 5024 basketball shots from 40 basketball games and 5 different levels of competitive basketball (National Basketball Association (NBA), Euroleague, Slovenian 1st Division, and two Youth basketball competitions). Statistical analysis with hierarchical multinomial logistic regression models reveals that there are substantial differences between competitions. However, most differences decrease or disappear entirely after we adjust for differences in situations that arise in different competitions (shot location, player type, and attacks in transition). Differences after adjustment are mostly between the Senior and Youth competitions: more shots executed jumping or standing on one leg, more uncategorised shot types, and more dribbling or cutting to the basket in the Youth competitions, which can all be attributed to lesser technical and physical ability of developing basketball players. The two discernible differences within the Senior competitions are that, in the NBA, dunks are more frequent and hook shots are less frequent compared to European basketball, which can be attributed to better athleticism of NBA players. The effect situational variables have on shot types and shot success are found to be very similar for all competitions. PMID:26038836

  20. Basketball Shot Types and Shot Success in Different Levels of Competitive Basketball

    PubMed Central

    2015-01-01

    The purpose of our research was to investigate the relative frequencies of different types of basketball shots (above head, hook shot, layup, dunk, tip-in), some details about their technical execution (one-legged, two-legged, drive, cut, …), and shot success in different levels of basketball competitions. We analysed video footage and categorized 5024 basketball shots from 40 basketball games and 5 different levels of competitive basketball (National Basketball Association (NBA), Euroleague, Slovenian 1st Division, and two Youth basketball competitions). Statistical analysis with hierarchical multinomial logistic regression models reveals that there are substantial differences between competitions. However, most differences decrease or disappear entirely after we adjust for differences in situations that arise in different competitions (shot location, player type, and attacks in transition). Differences after adjustment are mostly between the Senior and Youth competitions: more shots executed jumping or standing on one leg, more uncategorised shot types, and more dribbling or cutting to the basket in the Youth competitions, which can all be attributed to lesser technical and physical ability of developing basketball players. The two discernible differences within the Senior competitions are that, in the NBA, dunks are more frequent and hook shots are less frequent compared to European basketball, which can be attributed to better athleticism of NBA players. The effect situational variables have on shot types and shot success are found to be very similar for all competitions. PMID:26038836

  1. Multifractal properties of ball milling dynamics

    SciTech Connect

    Budroni, M. A. Pilosu, V.; Rustici, M.; Delogu, F.

    2014-06-15

    This work focuses on the dynamics of a ball inside the reactor of a ball mill. We show that the distribution of collisions at the reactor walls exhibits multifractal properties in a wide region of the parameter space defining the geometrical characteristics of the reactor and the collision elasticity. This feature points to the presence of restricted self-organized zones of the reactor walls where the ball preferentially collides and the mechanical energy is mainly dissipated.

  2. On the nonlinear modeling of shot noise

    PubMed Central

    Eliazar, Iddo; Klafter, Joseph

    2005-01-01

    We introduced a nonlinear shot-noise model, a natural generalization of the “classic” shot-noise model, which differs markedly from the existing linear shot-noise models. This model produces a wide spectrum of stationary noise processes. Because of its intrinsic nonlinearity, the model's resulting noise processes are capable of displaying a rich variety of both amplitudal and temporal statistical behaviors. Surprisingly, the nonlinear model is amenable to mathematical analysis and yields closed-form formulae for the characterizing statistics of its resulting noise processes. PMID:16172376

  3. Hidden symmetries and black holes

    NASA Astrophysics Data System (ADS)

    Frolov, Valeri P.

    2009-10-01

    The paper contains a brief review of recent results on hidden symmetries in higher dimensional black hole spacetimes. We show how the existence of a principal CKY tensor (that is a closed conformal Killing-Yano 2-form) allows one to generate a `tower' of Killing-Yano and Killing tensors responsible for hidden symmetries. These symmetries imply complete integrability of geodesic equations and the complete separation of variables in the Hamilton-Jacobi, Klein-Gordon, Dirac and gravitational perturbation equations in the general Kerr-NUT-(A)dS metrics. Equations of the parallel transport of frames along geodesics in these spacetimes are also integrable.

  4. Hidden symmetries in jammed systems

    NASA Astrophysics Data System (ADS)

    Morse, Peter K.; Corwin, Eric I.

    2016-07-01

    There are deep, but hidden, geometric structures within jammed systems, associated with hidden symmetries. These can be revealed by repeated transformations under which these structures lead to fixed points. These geometric structures can be found in the Voronoi tesselation of space defined by the packing. In this paper we examine two iterative processes: maximum inscribed sphere (MIS) inversion and a real-space coarsening scheme. Under repeated iterations of the MIS inversion process we find invariant systems in which every particle is equal to the maximum inscribed sphere within its Voronoi cell. Using a real-space coarsening scheme we reveal behavior in geometric order parameters which is length-scale invariant.

  5. 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.

  6. 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.

  7. 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.

  8. I-ball formation with logarithmic potential

    SciTech Connect

    Kawasaki, Masahiro; Takeda, Naoyuki E-mail: takedan@icrr.u-tokyo.ac.jp

    2014-07-01

    A coherently oscillating real scalar field with potential shallower than quadratic one fragments into spherical objects called I-balls. We study the I-ball formation for logarithmic potential which appears in many cosmological models. We perform lattice simulations and find that the I-balls are formed when the potential becomes dominated by the quadratic term. Furthermore, we estimate the I-ball profile assuming that the adiabatic invariant is conserved during formation and obtain the result that agrees to the numerical simulations.

  9. 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.

  10. Between Shots TRANSP Web Service

    NASA Astrophysics Data System (ADS)

    Feibush, E.; Andre, R.; Ludescher-Furth, C.; Kaye, S.; McCune, D.

    2008-11-01

    Running TRANSP between NSTX shots requires rapid data preparation and job submittal. A web service with a graphical user interface and data visualization has been developed to meet these goals. The underlying data preparation system has a command line interface written in Python and runs on a PPPL compute server. The display client is a Java program (ElVis) that sends requests to the data preparation system. As the run data is prepared, graphs are created and sent to the client for display. Flux surface plots are displayed and animated over time. The most commonly used control options are implemented in the UI as buttons and text fields. A time slice or time dependent run can be prepared. The command line interface is available in the client program for expert users to apply advanced settings, to prototype new UI buttons, and to run scripts. The client program contains a simple text editor for modifying the TRANSP namelist. When data preparation is complete the run is submitted to the TRANSP production system. The initial version has been deployed and is being tested in the control room setting. Results will be discussed in the poster presentation. Work performed at PPPL under the auspices of U.S. DOE Contract DE-AC02-76CH03073.

  11. The Soccer-Ball Problem

    NASA Astrophysics Data System (ADS)

    Hossenfelder, Sabine

    2014-07-01

    The idea that Lorentz-symmetry in momentum space could be modified but still remain observer-independent has received quite some attention in the recent years. This modified Lorentz-symmetry, which has been argued to arise in Loop Quantum Gravity, is being used as a phenomenological model to test possibly observable effects of quantum gravity. The most pressing problem in these models is the treatment of multi-particle states, known as the 'soccer-ball problem'. This article briefly reviews the problem and the status of existing solution attempts.

  12. POST-SHOT RADIATION ENVIRONMENT FOLLOWING LOW-YIELD SHOTS INSIDE THE NATIONAL IGNITION FACILITY

    SciTech Connect

    Sitaraman, S; Brereton, S; Dauffy, L; Hall, J; Hansen, L; Khater, H; Kim, S; Pohl, B; Verbeke, J

    2010-10-29

    A detailed model of the Target Bay (TB) at the National Ignition Facility (NIF) has been developed to estimate the post-shot radiation environment inside the facility. The model includes large number of structures and diagnostic instruments present inside the TB. These structures and instruments are activated by the few nanosecond pulse of neutrons generated during a shot and the resultant gamma dose rates are estimated at various decay times following the shot. The results presented in this paper are based on a low-yield D-T shot of 10{sup 16} neutrons. General environment dose rates drop to below 3 mrem/h within three hours following a shot with higher dose rates observed at contact with some of the components. Dose rate maps of the different TB levels were generated to aid in estimating worker stay-out times following a shot before entry is permitted into the TB.

  13. Our Hidden Prejudices, on Trial

    ERIC Educational Resources Information Center

    Glenn, David

    2008-01-01

    In October 2006, a New Hampshire police officer named Michael Briggs was shot to death in an alley. His accused killer, Michael Addison, has been charged with capital murder. It is the state's first death-penalty case in more than 30 years, and it is racially fraught: Addison is African-American, and Briggs was white. New Hampshire has a long list…

  14. Pregnant Women Need a Flu Shot

    MedlinePlus

    ... antibodies after getting flu vaccine. Talk to your doctor, nurse, or clinic about getting vaccinated as soon as ... have already had a flu shot--call your doctor, nurse, or clinic right away. Doctors can prescribe medicine ...

  15. Expectant Mom's Flu Shot Protects 2

    MedlinePlus

    ... infant records. Information was available for nine flu seasons from December 2005 through March 2014. Only about ... shot during any trimester of pregnancy during flu season, Tan said. The new study found that 97 ...

  16. Whooping Cough Shot Safe for Pregnant Women

    MedlinePlus

    ... fullstory_158983.html Whooping Cough Shot Safe for Pregnant Women It also offers short-term protection to ... News) -- The whooping cough vaccine is safe for pregnant women, a new study indicates. The researchers also ...

  17. Whooping Cough Shot Safe for Pregnant Women

    MedlinePlus

    ... nih.gov/medlineplus/news/fullstory_158983.html Whooping Cough Shot Safe for Pregnant Women It also offers ... MONDAY, May 23, 2016 (HealthDay News) -- The whooping cough vaccine is safe for pregnant women, a new ...

  18. Scalable learning method for feedforward neural networks using minimal-enclosing-ball approximation.

    PubMed

    Wang, Jun; Deng, Zhaohong; Luo, Xiaoqing; Jiang, Yizhang; Wang, Shitong

    2016-06-01

    Training feedforward neural networks (FNNs) is one of the most critical issues in FNNs studies. However, most FNNs training methods cannot be directly applied for very large datasets because they have high computational and space complexity. In order to tackle this problem, the CCMEB (Center-Constrained Minimum Enclosing Ball) problem in hidden feature space of FNN is discussed and a novel learning algorithm called HFSR-GCVM (hidden-feature-space regression using generalized core vector machine) is developed accordingly. In HFSR-GCVM, a novel learning criterion using L2-norm penalty-based ε-insensitive function is formulated and the parameters in the hidden nodes are generated randomly independent of the training sets. Moreover, the learning of parameters in its output layer is proved equivalent to a special CCMEB problem in FNN hidden feature space. As most CCMEB approximation based machine learning algorithms, the proposed HFSR-GCVM training algorithm has the following merits: The maximal training time of the HFSR-GCVM training is linear with the size of training datasets and the maximal space consumption is independent of the size of training datasets. The experiments on regression tasks confirm the above conclusions. PMID:27049545

  19. Preschoolers Search for Hidden Objects

    ERIC Educational Resources Information Center

    Haddad, Jeffrey M.; Chen, Yuping; Keen, Rachel

    2011-01-01

    The issue of whether young children use spatio-temporal information (e.g., movement of objects through time and space) and/or contact-mechanical information (e.g., interaction between objects) to search for a hidden object was investigated. To determine whether one cue can have priority over the other, a dynamic event that put these cues into…

  20. Hidden Costs of School Construction.

    ERIC Educational Resources Information Center

    Glass, Thomas E.

    1999-01-01

    Costs that may increase the original school construction estimates include school-design inefficiency, architect fees, and costs for land, site development, technology, demolition, consultants, and security. A quality-review team can plan to avoid hidden costs and ensure that the new facility will meet instructional needs at the least possible…

  1. The Hidden Dimensions of Databases.

    ERIC Educational Resources Information Center

    Jacso, Peter

    1994-01-01

    Discusses methods of evaluating commercial online databases and provides examples that illustrate their hidden dimensions. Topics addressed include size, including the number of records or the number of titles; the number of years covered; and the frequency of updates. Comparisons of Readers' Guide Abstracts and Magazine Article Summaries are…

  2. Sexual Harrassment: A Hidden Problem.

    ERIC Educational Resources Information Center

    Sandler, Bernice R.; And Others

    1981-01-01

    The hidden but serious problem of sexual harassment of students and employees by college faculty is discussed, some statistics are given, and legal and court opinions outlined. Harassment as a violation of Title IX is analyzed, and implications for institutional action to curb it are outlined. (MSE)

  3. Using Ruby Balls As Fiducial Marks

    NASA Technical Reports Server (NTRS)

    Painter, Nance M.

    1990-01-01

    Combination of basic and advanced techniques yields new capability for inspection. In new technique, surface first inspected with fluorescent penetrant dye to reveal flaws. Ruby ball of known diameter placed near flaw having to be measured. Flaw and ball observed through magnifying video system that can "freeze" image.

  4. NCI and Leidos Play Ball | Poster

    Cancer.gov

    By Carolynne Keenan, Contributing Writer The ping of an aluminum bat off a ball or the thump of a pop-up fly ball caught in a glove are two sounds familiar to baseball fans. Slow-pitch softball sounds—like those in the August game between mixed teams of NCI and Leidos Biomedical Research (formerly SAIC-Frederick) players—are similar.

  5. Flicker Ball, Physical Education: 5551.34.

    ERIC Educational Resources Information Center

    Stout, Paul L.

    This course outline is a guide for teaching skills of flicker ball in grades 7-12. The course format includes lectures, game situations, class tournaments, and tests that focus on mastery of skills, understanding of rules, and development of techniques in shooting and passing. Course content includes the following: (a) history of flicker ball, (b)…

  6. Some Mathematics and Physics of Ball Games.

    ERIC Educational Resources Information Center

    Hughes, D. E.

    1985-01-01

    Gives examples on the applications of arithmetic, geometry, and some calculus, vector algebra, and mechanics to ball games. Suggestions for further interesting investigations are provided together with references to other articles and books on applications of mathematics and physics to ball games and sports in general. (JN)

  7. Soccer Ball Lift Coefficients via Trajectory Analysis

    ERIC Educational Resources Information Center

    Goff, John Eric; Carre, Matt J.

    2010-01-01

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin…

  8. The effects of increased shooting distance in the basketball jump shot.

    PubMed

    Miller, S; Bartlett, R M

    1993-08-01

    Three-dimensional video techniques (50 Hz) were used to obtain images of basketball jump shots from one of three distances--short range (group 1, n = 5); medium range (group 2, n = 5); long range (group 3, n = 5)--from the basket, as performed by members of the men's quarter-finalist teams at the games of the XVI Universiade in Sheffield in 1991. Fifteen sequences were digitized, beginning 20 frames prior to take-off to 10 frames after release. To facilitate analysis, the sequences were rotated about the ball position in the final frame so that the shot direction was parallel to one of the pre-defined orthogonal axes. Mean (+/- 1 S.D.) ball release speed was found to increase with distance from the basket (group 1 = 3.04 +/- 0.65 m s-1, group 2 = 4.71 +/- 0.74 m s-1, group 3 = 6.24 +/- 0.80 m s-1), while mean release angles were similar for all groups (group 1 = 48.8 +/- 10.1 degrees, group 2 = 47.8 +/- 5.8 degrees, group 3 = 51.9 +/- 5.5 degrees). The increased impulse necessary for the ball to reach the basket at increased shooting distances was derived from both an increase in angular velocity of the elbow joint of the shooting arm and an increased velocity of the centre of mass in the direction of the basket at release. Centre of mass speed at take-off was found to be influenced to a greater extent by the angular velocity of the ankle joint than that of the knee or hip joints.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8230388

  9. Effect of different number of players and training regimes on physiological and technical demands of ball-drills in basketball.

    PubMed

    Conte, Daniele; Favero, Terence G; Niederhausen, Meike; Capranica, Laura; Tessitore, Antonio

    2016-01-01

    This study aimed to analyse the effects of two factors (number of players and training regimes) on players' physiological and technical demands in basketball ball-drills. Twenty-one young basketball players performed four different ball-drills (two levels for each factor). The number of players involved was 2vs2 and 4vs4, while ball-drill regimes were continuous and intermittent. Physiological demand was assessed using the percentage of maximal heart rate (%HRmax), Edwards' training load and rating of perceived exertion (RPE). Furthermore, the following technical actions were collected: dribbles, steals, rebounds, turnovers, passes (total, correct, wrong and % of correct pass) and shots (total, scored, missed and % of made shot). A 2 × 2 (number of players × regime) two-way ANOVA with repeated measures was applied for physiological parameters and technical actions. The 2vs2 condition showed higher %HRmax (P < 0.001), Edwards' training load (P < 0.001), RPE (P < 0.001), number of dribbles (P < 0.001), rebounds (P < 0.001), passes [total (P = 0.005) and correct (P = 0.005)] and shots [total (P < 0.001) scored (P < 0.001) and missed (P < 0.001)] than 4vs4. Moreover, the continuous regime revealed higher %HRmax (P < 0.001), Edwards' training load (P < 0.001), RPE (P = 0.006) and dribbles (P < 0.001) than the intermittent regime. This study showed that both number of players and regime are useful variables able to modify basketball ball-drills workload. PMID:26208533

  10. Ball bearing heat analysis program (BABHAP)

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The Ball Bearing Heat Analysis Program (BABHAP) is an attempt to assemble a series of equations, some of which are non-linear algebraic systems, in a logical order, which when solved, provide a complex analysis of load distribution among the balls, ball velocities, heat generation resulting from friction, applied load, and ball spinning, minimum lubricant film thickness, and many additional characteristics of ball bearing systems. Although initial design requirements for BABHAP were dictated by the core limitations of the PDP 11/45 computer, (approximately 8K of real words with limited number of instructions) the program dimensions can easily be expanded for large core computers such as the UNIVAC 1108. The PDP version of BABHAP is also operational on the UNIVAC system with the exception that the PDP uses 029 punch and the UNIVAC uses 026. A conversion program was written to allow transfer between machines.

  11. F-term inflation Q-balls

    SciTech Connect

    McDonald, John

    2006-02-15

    A general analysis of Q-ball solutions of the supersymmetric F-term hybrid inflation field equations is given. The solutions consist of a complex inflaton field and a real symmetry-breaking field, with a conserved global charge associated with the inflaton. It is shown that the Q-ball solutions for any value of the superpotential coupling, {kappa}, may be obtained from those with {kappa}=1 by rescaling the space coordinates. The complete range of Q-ball solutions for the case {kappa}=1 is given, from which all possible F-term inflation Q-balls can be obtained. The possible role of F-term inflation Q-balls in cosmology is discussed.

  12. Prediction of shot success for basketball free throws: visual search strategy.

    PubMed

    Uchida, Yusuke; Mizuguchi, Nobuaki; Honda, Masaaki; Kanosue, Kazuyuki

    2014-01-01

    In ball games, players have to pay close attention to visual information in order to predict the movements of both the opponents and the ball. Previous studies have indicated that players primarily utilise cues concerning the ball and opponents' body motion. The information acquired must be effective for observing players to select the subsequent action. The present study evaluated the effects of changes in the video replay speed on the spatial visual search strategy and ability to predict free throw success. We compared eye movements made while observing a basketball free throw by novices and experienced basketball players. Correct response rates were close to chance (50%) at all video speeds for the novices. The correct response rate of experienced players was significantly above chance (and significantly above that of the novices) at the normal speed, but was not different from chance at both slow and fast speeds. Experienced players gazed more on the lower part of the player's body when viewing a normal speed video than the novices. The players likely detected critical visual information to predict shot success by properly moving their gaze according to the shooter's movements. This pattern did not change when the video speed was decreased, but changed when it was increased. These findings suggest that temporal information is important for predicting action outcomes and that such outcomes are sensitive to video speed. PMID:24319995

  13. The effect of introducing a smaller and lighter basketball on female basketball players' shot accuracy.

    PubMed

    Podmenik, Nadja; Leskošek, Bojan; Erčulj, Frane

    2012-03-01

    Our study examined whether the introduction of a smaller and lighter basketball (no. 6) affected the accuracy of female basketball players' shots at the basket. The International Basketball Federation (FIBA) introduced a size 6 ball in the 2004/2005 season to improve the efficiency and accuracy of technical elements, primarily shots at the basket. The sample for this study included 573 European female basketball players who were members of national teams that had qualified for the senior women's European championships in 2001, 2003, 2005 and 2007. A size 7 (larger and heavier) basketball was used by 286 players in 1,870 matches, and a size 6 basketball was used by 287 players in 1,966 matches. The players were categorised into three playing positions: guards, forwards and centres. The results revealed that statistically significant changes by year occurred only in terms of the percentage of successful free throws. With the size 6 basketball, this percentage decreased. Statistically significant differences between the playing positions were observed in terms of the percentage of field goals worth three points (between guards and forwards) and two points (between guards and centres). The results show that the introduction of the size 6 basketball did not lead to improvement in shooting accuracy (the opposite was found for free throws), although the number of three-point shots increased. PMID:23486286

  14. The Effect of Introducing a Smaller and Lighter Basketball on Female Basketball Players’ Shot Accuracy

    PubMed Central

    Podmenik, Nadja; Leskošek, Bojan; Erčulj, Frane

    2012-01-01

    Our study examined whether the introduction of a smaller and lighter basketball (no. 6) affected the accuracy of female basketball players’ shots at the basket. The International Basketball Federation (FIBA) introduced a size 6 ball in the 2004/2005 season to improve the efficiency and accuracy of technical elements, primarily shots at the basket. The sample for this study included 573 European female basketball players who were members of national teams that had qualified for the senior women’s European championships in 2001, 2003, 2005 and 2007. A size 7 (larger and heavier) basketball was used by 286 players in 1,870 matches, and a size 6 basketball was used by 287 players in 1,966 matches. The players were categorised into three playing positions: guards, forwards and centres. The results revealed that statistically significant changes by year occurred only in terms of the percentage of successful free throws. With the size 6 basketball, this percentage decreased. Statistically significant differences between the playing positions were observed in terms of the percentage of field goals worth three points (between guards and forwards) and two points (between guards and centres). The results show that the introduction of the size 6 basketball did not lead to improvement in shooting accuracy (the opposite was found for free throws), although the number of three-point shots increased. PMID:23486286

  15. An On-Line Algorithm for Measuring the Translational and Rotational Velocities of a Table Tennis Ball

    NASA Astrophysics Data System (ADS)

    Liu, Chunfang; Hayakawa, Yoshikazu; Nakashima, Akira

    This paper proposes an on-line method for estimating both translational and rotational velocities of a table tennis ball by using only a few consecutive frames of image data which are sensed by two high speed cameras. In order to estimate the translational velocity, three-dimensional (3D) position of the ball's center at each instant of camera frame is obtained, where the on-line method of reconstructing the 3D position from the two-dimensional (2D) image data of two cameras is proposed without the pattern matching process. The proposed method of estimating the rotational velocity belongs to the image registration methods, where in order to avoid the pattern matching process too, a rotation model of the ball is used to make an estimated image data from an image data sensed at the previous instant of camera frame and then the estimated image data are compared with the image data sensed at the next instant of camera frame to obtain the most plausible rotational velocity by using the least square and the conjugate gradient method. The effectiveness of the proposed method is shown by some experimental results in the case of a ball rotated by a rotation machine as well as in the case of a flying ball shot from a catapult machine.

  16. Bouncing steel balls on water

    NASA Astrophysics Data System (ADS)

    de Podesta, Michael

    2007-09-01

    The 'skimming' of stones on water is a subject of perennial fascination for children and adults alike. In this article I describe the construction of an apparatus for safely and reproducibly demonstrating a similar phenomenon: the bouncing of 25 mm diameter steel balls from a water surface. The 'bouncing' is technically known as a ricochet and the article recounts the use of the effect in the Second World War in the 'Dam Busting' air raids of 1943. A number of calculations are made which allow an estimate of the projectile speed and energy, and the use of simple experimental techniques for validating these estimates is suggested. The role of spin is discussed, and a literature review collates the available empirical and theoretical results concerning the incident angle and speed for successful ricochet of spinning and non-spinning projectiles.

  17. Ready for the Cosmic Ball

    NASA Technical Reports Server (NTRS)

    2006-01-01

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

    NGC 2207 and IC 2163 recently met and began a sort of gravitational tango about 40 million years ago. The two galaxies are tugging at each other, stimulating new stars to form. Eventually, this cosmic ball will come to an end, when the galaxies meld into one. The dancing duo is located 140 million light-years away in the Canis Major constellation.

    The Spitzer image reveals that the galactic mask is adorned with strings of pearl-like beads. These dusty clusters of newborn stars, called 'beads on a string' by astronomers, appear as white balls throughout the arms of both galaxies. They were formed when the galaxies first interacted, forcing dust and gas to clump together into colonies of stars.

    This type of beading has been seen before in other galaxies, but it took Spitzer's infrared eyes to identify them in NGC 2207 and IC 2163. Spitzer was able to see the beads because the stars inside heat up surrounding dust, which then radiates with infrared light.

    The biggest bead lighting up the left side of the mask is also the densest. In fact, some of its central stars might have merged to form a black hole. (Now, that would be quite the Mardi Gras mask!)

    This picture, taken by Spitzer's infrared array camera, is a four-channel composite. It shows light with wavelengths of 3.6 microns (blue); 4.5 microns (green); and 5.8 and 8.0 microns (red). The contribution from starlight (measured at 3.6 microns) has been subtracted from the 5.8- and 8-micron channels to enhance the visibility of the dust features.

  18. 50 CFR 20.134 - Approval of nontoxic shot types and shot coatings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... will add the shot material to the list of approved nontoxic shot materials at 50 CFR 20.21(j). (a... of Sewage Sludge at 40 CFR part 503. Explain how the estimated EEC relates to the toxicity thresholds... Practice Standards (40 CFR part 160) except where they conflict with the requirements in this section...

  19. Indirect monitoring shot-to-shot shock waves strength reproducibility during pump-probe experiments

    NASA Astrophysics Data System (ADS)

    Pikuz, T. A.; Faenov, A. Ya.; Ozaki, N.; Hartley, N. J.; Albertazzi, B.; Matsuoka, T.; Takahashi, K.; Habara, H.; Tange, Y.; Matsuyama, S.; Yamauchi, K.; Ochante, R.; Sueda, K.; Sakata, O.; Sekine, T.; Sato, T.; Umeda, Y.; Inubushi, Y.; Yabuuchi, T.; Togashi, T.; Katayama, T.; Yabashi, M.; Harmand, M.; Morard, G.; Koenig, M.; Zhakhovsky, V.; Inogamov, N.; Safronova, A. S.; Stafford, A.; Skobelev, I. Yu.; Pikuz, S. A.; Okuchi, T.; Seto, Y.; Tanaka, K. A.; Ishikawa, T.; Kodama, R.

    2016-07-01

    We present an indirect method of estimating the strength of a shock wave, allowing on line monitoring of its reproducibility in each laser shot. This method is based on a shot-to-shot measurement of the X-ray emission from the ablated plasma by a high resolution, spatially resolved focusing spectrometer. An optical pump laser with energy of 1.0 J and pulse duration of ˜660 ps was used to irradiate solid targets or foils with various thicknesses containing Oxygen, Aluminum, Iron, and Tantalum. The high sensitivity and resolving power of the X-ray spectrometer allowed spectra to be obtained on each laser shot and to control fluctuations of the spectral intensity emitted by different plasmas with an accuracy of ˜2%, implying an accuracy in the derived electron plasma temperature of 5%-10% in pump-probe high energy density science experiments. At nano- and sub-nanosecond duration of laser pulse with relatively low laser intensities and ratio Z/A ˜ 0.5, the electron temperature follows Te ˜ Ilas2/3. Thus, measurements of the electron plasma temperature allow indirect estimation of the laser flux on the target and control its shot-to-shot fluctuation. Knowing the laser flux intensity and its fluctuation gives us the possibility of monitoring shot-to-shot reproducibility of shock wave strength generation with high accuracy.

  20. 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.

  1. Viscoelastic modelling of tennis ball properties

    NASA Astrophysics Data System (ADS)

    Sissler, L.; Jones, R.; Leaney, P. G.; Harland, A.

    2010-06-01

    An explicit finite element (FE) tennis ball model which illustrates the effects of the viscoelastic materials of a tennis ball on ball deformation and bounce during normal impacts is presented. A tennis ball is composed of a rubber core and a fabric cover comprised of a wool-nylon mix which exhibit non-linear strain rate properties during high velocity impacts. The rubber core model was developed and validated using low strain rate tensile tests on rubber samples as well as high velocity normal impacts of pressurised cores at velocities ranging from 15 m/s to 50 m/s. The impacts were recorded using a high speed video (HSV) camera to determine deformation, impact time and coefficient of restitution (COR). The material properties of the core model were tuned to match the HSV results. A two component anisotropic fabric model was created which included artificial Rayleigh damping to account for hysteresis effects, and the core model 'tuning' process was used to refine the cloth layer. The ball model's parameters were in good agreement with experimental data at all velocities for both cores and complete balls, and a time sequenced comparison of HSV ball motion and FE model confirmed the validity of the model.

  2. BALL - biochemical algorithms library 1.3

    PubMed Central

    2010-01-01

    Background The Biochemical Algorithms Library (BALL) is a comprehensive rapid application development framework for structural bioinformatics. It provides an extensive C++ class library of data structures and algorithms for molecular modeling and structural bioinformatics. Using BALL as a programming toolbox does not only allow to greatly reduce application development times but also helps in ensuring stability and correctness by avoiding the error-prone reimplementation of complex algorithms and replacing them with calls into the library that has been well-tested by a large number of developers. In the ten years since its original publication, BALL has seen a substantial increase in functionality and numerous other improvements. Results Here, we discuss BALL's current functionality and highlight the key additions and improvements: support for additional file formats, molecular edit-functionality, new molecular mechanics force fields, novel energy minimization techniques, docking algorithms, and support for cheminformatics. Conclusions BALL is available for all major operating systems, including Linux, Windows, and MacOS X. It is available free of charge under the Lesser GNU Public License (LPGL). Parts of the code are distributed under the GNU Public License (GPL). BALL is available as source code and binary packages from the project web site at http://www.ball-project.org. Recently, it has been accepted into the debian project; integration into further distributions is currently pursued. PMID:20973958

  3. 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.

  4. Numerical simulation of ball-racket impact

    NASA Astrophysics Data System (ADS)

    Yu, Yingpang

    The collision of a ball with a tennis racket is usually modeled in terms of rigid body dynamics or an elastic system involving only a few springs. In this paper, we study the impact between a tennis ball and racket, by modeling the tennis ball in two different yaws. One method models the tennis ball as a Hertz elastic body and the other one models the ball by a more accurate finite element analysis. In the first model, we assume that the elastic properties of the ball obeys Hertz's law. In the finite element model, we consider the tennis ball as a shell witch is a elastic system constructed out of many isotropic small linear flat, elements, witch have both elastic and damping properties. The damping in each way is approximated as viscous term. In both methods, we study the static condition of deformation against a rigid surface before applying these models to dynamical processes. We compare these two methods and eventually determine how the racket parameters effect the performance of the racket, using numerical simulations. Comparison with experiment are show to confirm the general conclusion of the model.

  5. Titanium carbide coatings for aerospace ball bearings

    NASA Technical Reports Server (NTRS)

    Boving, Hans J.; Haenni, Werner; Hintermann, HANS-E.

    1988-01-01

    In conventional ball bearings, steel to steel contacts between the balls and the raceways are at the origin of microwelds which lead to material transfer, surface roughening, lubricant breakdown, and finally to a loss in the bearing performances. To minimize the microwelding tendencies of the contacting partners it is necessary to modify their surface materials; the solid to solid collisions themselves are difficult to avoid. The use of titanium carbide coated steel balls can bring spectacular improvements in the performances and lifetimes of both oil-grease lubricated and oil-grease free bearings in a series of severe applications.

  6. Shock-Absorbent Ball-Screw Mechanism

    NASA Technical Reports Server (NTRS)

    Hirr, Otto A., Jr.; Meneely, R. W.

    1986-01-01

    Actuator containing two ball screws in series employs Belleville springs to reduce impact loads, thereby increasing life expectancy. New application of springs increases reliability of equipment in which ball screws commonly used. Set of three springs within lower screw of ball-screw mechanism absorbs impacts that result when parts reach their upper and lower limits of movement. Mechanism designed with Belleville springs as shock-absorbing elements because springs have good energy-to-volume ratio and easily stacked to attain any stiffness and travel.

  7. Designing Hollow Nano Gold Golf Balls

    PubMed Central

    2015-01-01

    Hollow/porous nanoparticles, including nanocarriers, nanoshells, and mesoporous materials have applications in catalysis, photonics, biosensing, and delivery of theranostic agents. Using a hierarchical template synthesis scheme, we have synthesized a nanocarrier mimicking a golf ball, consisting of (i) solid silica core with a pitted gold surface and (ii) a hollow/porous gold shell without silica. The template consisted of 100 nm polystyrene beads attached to a larger silica core. Selective gold plating of the core followed by removal of the polystyrene beads produced a golf ball-like nanostructure with 100 nm pits. Dissolution of the silica core produced a hollow/porous golf ball-like nanostructure. PMID:24937196

  8. Craniofacial reconstruction using rational cubic ball curves.

    PubMed

    Majeed, Abdul; Mt Piah, Abd Rahni; Gobithaasan, R U; Yahya, Zainor Ridzuan

    2015-01-01

    This paper proposes the reconstruction of craniofacial fracture using rational cubic Ball curve. The idea of choosing Ball curve is based on its robustness of computing efficiency over Bezier curve. The main steps are conversion of Digital Imaging and Communications in Medicine (Dicom) images to binary images, boundary extraction and corner point detection, Ball curve fitting with genetic algorithm and final solution conversion to Dicom format. The last section illustrates a real case of craniofacial reconstruction using the proposed method which clearly indicates the applicability of this method. A Graphical User Interface (GUI) has also been developed for practical application. PMID:25880632

  9. Q-balls in flat potentials

    SciTech Connect

    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.

  10. Improved Ball-and-Socket Docking Mechanism

    NASA Technical Reports Server (NTRS)

    Cloyd, Richard; Bryan, Tom

    2004-01-01

    A proposed docking mechanism would form a ball-and-socket joint in the docked condition. The mechanism could tolerate significant initial misalignment because it would include an alignment cone that would guide the ball into the socket. Like other ball-and-socket joints, the joint would have three rotational degrees of freedom. This docking mechanism would be a successor to the one described in Passive Capture Joint With Three Degrees of Freedom (MFS-31146), NASA Tech Briefs, Vol. 22, No. 7 (July 1998), page 65. It would contain most of the components of the prior mechanism, plus some additional components that would expand its capabilities.

  11. Rotating boson stars and Q-balls

    SciTech Connect

    Kleihaus, Burkhard; Kunz, Jutta; List, Meike

    2005-09-15

    We consider axially symmetric, rotating boson stars. Their flat-space limits represent spinning Q-balls. We discuss their properties and determine their domain of existence. Q-balls and boson stars are stationary solutions and exist only in a limited frequency range. The coupling to gravity gives rise to a spiral-like frequency dependence of the boson stars. We address the flat-space limit and the limit of strong gravitational coupling. For comparison we also determine the properties of spherically symmetric Q-balls and boson stars.

  12. Geometric optics and the "hairy ball theorem"

    NASA Astrophysics Data System (ADS)

    Bormashenko, Edward; Kazachkov, Alexander

    Applications of the hairy ball theorem to the geometrical optics are discussed. When the ideal mirror, topologically equivalent to a sphere, is illuminated at every point, the "hairy ball theorem" prescribes the existence of at least one point at which the incident light will be normally reflected. For the more general case of the surface, topologically equivalent to a sphere, which is both reflecting and refracting the "hairy ball theorem" predicts the existence of at least one point, at which the incident light will be normally reflected and also normally refracted.

  13. Trajectory analysis of a soccer ball

    NASA Astrophysics Data System (ADS)

    Goff, John Eric; Carré, Matt J.

    2009-11-01

    We performed experiments in which a soccer ball was launched from a machine while two cameras recorded portions of its trajectory. Drag coefficients were obtained from range measurements for no-spin trajectories, for which the drag coefficient does not vary appreciably during the ball's flight. Lift coefficients were obtained from the trajectories immediately following the ball's launch, in which Reynolds number and spin parameter do not vary much. We obtain two values of the lift coefficient for spin parameters that had not been obtained previously. Our codes for analyzing the trajectories are freely available to educators and students.

  14. Craniofacial Reconstruction Using Rational Cubic Ball Curves

    PubMed Central

    Majeed, Abdul; Mt Piah, Abd Rahni; Gobithaasan, R. U.; Yahya, Zainor Ridzuan

    2015-01-01

    This paper proposes the reconstruction of craniofacial fracture using rational cubic Ball curve. The idea of choosing Ball curve is based on its robustness of computing efficiency over Bezier curve. The main steps are conversion of Digital Imaging and Communications in Medicine (Dicom) images to binary images, boundary extraction and corner point detection, Ball curve fitting with genetic algorithm and final solution conversion to Dicom format. The last section illustrates a real case of craniofacial reconstruction using the proposed method which clearly indicates the applicability of this method. A Graphical User Interface (GUI) has also been developed for practical application. PMID:25880632

  15. SnapShot: Expanding the Ubiquitin Code.

    PubMed

    Rajalingam, Krishnaraj; Dikic, Ivan

    2016-02-25

    The Ubiquitin (Ub) system coordinates vital cellular processes by controlling lifetime, signaling, and binding properties of proteins. Ub serves as a multivalent protein tag that is further diversified by post-translational modifications. Specialized Ub receptors then convert the encoded signals into cellular responses. This SnapShot highlights the importance of the rapidly expanding Ub code in biology as well as novel pharmacological approaches to target the Ub system in multiple diseases. To view this SnapShot, open or download the PDF. PMID:26919436

  16. SunShot Initiative Fact Sheet

    SciTech Connect

    DOE Solar Energy Technologies Office

    2015-04-01

    The U.S. Department of Energy (DOE) SunShot Initiative is a collaborative national effort launched in 2011 that aggressively drives innovation to make solar energy fully cost competitive with traditional energy sources before the end of the decade. The SunShot fact sheet outlines goals and successes of the program as it works with private companies, universities, non-profit organizations, state and local governments, and national laboratories to drive down the cost of solar electricity to $0.06 per kilowatt-hour, without incentives, by the year 2020.

  17. Production of ball-lightning-like luminous balls by electrical discharges in silicon.

    PubMed

    Paiva, Gerson Silva; Pavão, Antonio Carlos; Alpes de Vasconcelos, Elder; Mendes, Odim; da Silva, Eronides Felisberto

    2007-01-26

    We performed electric arc discharges in pure Si to generate luminous balls with lifetime in the order of seconds and several properties usually reported for natural ball lightning. This simple experiment does not rely on energy sources and excitation mechanisms that are improbable in the natural phenomenon and clearly demonstrates the role of vaporization and oxidation of Si, as proposed by the Abrahamson-Dinniss theory for ball-lightning formation. PMID:17358820

  18. Production of Ball-Lightning-Like Luminous Balls by Electrical Discharges in Silicon

    NASA Astrophysics Data System (ADS)

    Paiva, Gerson Silva; Pavão, Antonio Carlos; Alpes de Vasconcelos, Elder; Mendes, Odim, Jr.; Felisberto da Silva, Eronides, Jr.

    2007-01-01

    We performed electric arc discharges in pure Si to generate luminous balls with lifetime in the order of seconds and several properties usually reported for natural ball lightning. This simple experiment does not rely on energy sources and excitation mechanisms that are improbable in the natural phenomenon and clearly demonstrates the role of vaporization and oxidation of Si, as proposed by the Abrahamson-Dinniss theory for ball-lightning formation.

  19. Flexible timing of eye movements when catching a ball.

    PubMed

    López-Moliner, Joan; Brenner, Eli

    2016-01-01

    In ball games, one cannot direct ones gaze at the ball all the time because one must also judge other aspects of the game, such as other players' positions. We wanted to know whether there are times at which obtaining information about the ball is particularly beneficial for catching it. We recently found that people could catch successfully if they saw any part of the ball's flight except the very end, when sensory-motor delays make it impossible to use new information. Nevertheless, there may be a preferred time to see the ball. We examined when six catchers would choose to look at the ball if they had to both catch the ball and find out what to do with it while the ball was approaching. A catcher and a thrower continuously threw a ball back and forth. We recorded their hand movements, the catcher's eye movements, and the ball's path. While the ball was approaching the catcher, information was provided on a screen about how the catcher should throw the ball back to the thrower (its peak height). This information disappeared just before the catcher caught the ball. Initially there was a slight tendency to look at the ball before looking at the screen but, later, most catchers tended to look at the screen before looking at the ball. Rather than being particularly eager to see the ball at a certain time, people appear to adjust their eye movements to the combined requirements of the task. PMID:26982371

  20. Principles of Virus Uncoating: Cues and the Snooker Ball.

    PubMed

    Yamauchi, Yohei; Greber, Urs F

    2016-06-01

    Viruses are spherical or complex shaped carriers of proteins, nucleic acids and sometimes lipids and sugars. They are metastable and poised for structural changes. These features allow viruses to communicate with host cells during entry, and to release the viral genome, a process known as uncoating. Studies have shown that hundreds of host factors directly or indirectly support this process. The cell provides molecules that promote stepwise virus uncoating, and direct the virus to the site of replication. It acts akin to a snooker player who delivers accurate and timely shots (cues) to the ball (virus) to score. The viruses, on the other hand, trick (snooker) the host, hijack its homeostasis systems, and dampen innate immune responses directed against danger signals. In this review, we discuss how cellular cues, facilitators, and built-in viral mechanisms promote uncoating. Cues come from receptors, enzymes and chemicals that act directly on the virus particle to alter its structure, trafficking and infectivity. Facilitators are defined as host factors that are involved in processes which indirectly enhance entry or uncoating. Unraveling the mechanisms of virus uncoating will continue to enhance understanding of cell functions, and help counteracting infections with chemicals and vaccines. PMID:26875443

  1. Contact Sensors on Ceramic Ball Bearings

    NASA Astrophysics Data System (ADS)

    Yi, Jia; Just-Agosto, Frederick; Romero, Edwar

    2002-01-01

    Integration of micro contact sensors onto a ball bearing is a critical technology necessary for on-line bearing health monitoring in an industrial harsh environment and evaluation of the bearing performance and design. The current planner fabrication methods offered by the MEMS technology restrict the possibility of integrating micro sensor onto a double contoured bearing surface in a more traditional manufacturing environment. We have developed an unique technique to directly fabricate micron-sized pressure and temperature sensors onto a miniature ceramic ball bearing. A complete fabrication process, based on sensor design, surface preparation, optimized sputtering parameters, photolithographic techniques and sensor post-treatment, is described. Pressure and temperature measurement results on a miniature ceramic ball bearing show good correlation with numerical thermal-EHL analysis and good wear resistance. Keywords: Ball Bearing, Thin film Sensor, Pressure sensor, Temperature Sensor, adhesion, wear resistance, Non-developable surface, and thermal-EHL.

  2. Static Load Distribution in Ball Bearings

    NASA Technical Reports Server (NTRS)

    Ricci, Mario

    2010-01-01

    A numerical procedure for computing the internal loading distribution in statically loaded, single-row, angular-contact ball bearings when subjected to a known combined radial and thrust load is presented. The combined radial and thrust load must be applied in order to avoid tilting between inner and outer rings. The numerical procedure requires the iterative solution of Z + 2 simultaneous nonlinear equations - where Z is the number of the balls - to yield an exact solution for axial and radial deflections, and contact angles. Numerical results for a 218 angular-contact ball bearing have been compared with those from the literature and show significant differences in the magnitudes of the ball loads, contact angles, and the extent of the loading zone.

  3. 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.

  4. Discovering motion primitives for unsupervised grouping and one-shot learning of human actions, gestures, and expressions.

    PubMed

    Yang, Yang; Saleemi, Imran; Shah, Mubarak

    2013-07-01

    This paper proposes a novel representation of articulated human actions and gestures and facial expressions. The main goals of the proposed approach are: 1) to enable recognition using very few examples, i.e., one or k-shot learning, and 2) meaningful organization of unlabeled datasets by unsupervised clustering. Our proposed representation is obtained by automatically discovering high-level subactions or motion primitives, by hierarchical clustering of observed optical flow in four-dimensional, spatial, and motion flow space. The completely unsupervised proposed method, in contrast to state-of-the-art representations like bag of video words, provides a meaningful representation conducive to visual interpretation and textual labeling. Each primitive action depicts an atomic subaction, like directional motion of limb or torso, and is represented by a mixture of four-dimensional Gaussian distributions. For one--shot and k-shot learning, the sequence of primitive labels discovered in a test video are labeled using KL divergence, and can then be represented as a string and matched against similar strings of training videos. The same sequence can also be collapsed into a histogram of primitives or be used to learn a Hidden Markov model to represent classes. We have performed extensive experiments on recognition by one and k-shot learning as well as unsupervised action clustering on six human actions and gesture datasets, a composite dataset, and a database of facial expressions. These experiments confirm the validity and discriminative nature of the proposed representation. PMID:23681992

  5. Gravitational waves from Q-ball formation

    SciTech Connect

    Chiba, Takeshi; Kamada, Kohei; Yamaguchi, Masahide

    2010-04-15

    We study the detectability of the gravitational waves (GWs) from the Q-ball formation associated with the Affleck-Dine (AD) mechanism, taking into account both the dilution effects due to Q-ball domination and to finite temperature. The AD mechanism predicts the formation of nontopological solitons, Q-balls, from which GWs are generated. Q-balls with large conserved charge Q can produce a large amount of GWs. On the other hand, the decay rate of such Q-balls is so small that they may dominate the energy density of the Universe, which implies that GWs are significantly diluted and that their frequencies are redshifted during the Q-ball dominated era. Thus, the detectability of the GWs associated with the formation of Q-balls is determined by these two competing effects. We find that there is a finite but small parameter region where such GWs may be detected by future detectors such as DECIGO or BBO, only in the case when the thermal logarithmic potential dominates the potential of the AD field. Otherwise GWs from Q-balls would not be detectable even by these futuristic detectors: {Omega}{sub GW}{sup 0}<10{sup -21}. Unfortunately, for such parameter region the present baryon asymmetry of the Universe can hardly be explained unless one fine-tunes A-terms in the potential. However the detection of such a GW background may give us an information about the early Universe, for example, it may suggest that the flat directions with B-L=0 are favored.

  6. Heated-Pressure-Ball Monopropellant Rocket Engine

    NASA Technical Reports Server (NTRS)

    Greene, William D.

    2005-01-01

    A recent technology disclosure presents a concept for a monopropellant thermal spacecraft thruster that would feature both the simplicity of a typical prior pressure-fed propellant supply system and the smaller mass and relative compactness of a typical prior pump-fed system. The source of heat for this thruster would likely be a nuclear- fission reactor. The propellant would be a cryogenic fluid (a liquefied low-molecular-weight gas) stored in a tank at a low pressure. The propellant would flow from the tank, through a feedline, into three thick-walled spherical tanks, denoted pressure balls, that would be thermally connected to the reactor. Valves upstream and downstream of the pressure balls would be operated in a three-phase cycle in which propellant would flow into one pressure ball while the fluid underwent pressurization through heating in another ball and pressurized propellant was discharged from the remaining ball into the reactor. After flowing through the reactor, wherein it would be further heated, the propellant would be discharged through an exhaust nozzle to generate thrust. A fraction of the pressurized gas from the pressure balls would be diverted to maintain the desired pressure in the tank.

  7. Decaying hidden dark matter in warped compactification

    SciTech Connect

    Chen, Xingang

    2009-09-01

    The recent PAMELA and ATIC/Fermi/HESS experiments have observed an excess of electrons and positrons, but not anti-protons, in the high energy cosmic rays. To explain this result, we construct a decaying hidden dark matter model in string theory compactification that incorporates the following two ingredients, the hidden dark matter scenario in warped compactification and the phenomenological proposal of hidden light particles that decay to the Standard Model. In this model, on higher dimensional warped branes, various warped Kaluza-Klein particles and the zero-mode of gauge field play roles of the hidden dark matter or mediators to the Standard Model.

  8. Ultrasonics and Optics Would Control Shot Size

    NASA Technical Reports Server (NTRS)

    Morrison, A. D.

    1983-01-01

    Feedback system assures production of silicon shot of uniform size. Breakup of silicon stream into drops is controlled, in part, by varying frequency of vibrations imparted to stream by ultrasonic transducer. Drop size monitored by photodetector. Control method particularly advantageous in that constant size is maintained even while other process variables are changed deliberately or inadvertently. Applicable to materials other than silicon.

  9. Patronin Takes a Shot at Polarity.

    PubMed

    Takeichi, Masatoshi; Toya, Mika

    2016-07-11

    To specify the anterior-posterior axis of Drosophila embryos, noncentrosomal microtubules grow out from cortical regions of the oocyte and help transport axis determinants. In this issue of Developmental Cell, Nashchekin et al. (2016) report a Shot- and Patronin-dependent mechanism by which the oocyte cortex produces polarized microtubule arrays. PMID:27404355

  10. Dual echelon femtosecond single-shot spectroscopy

    SciTech Connect

    Shin, Taeho; Wolfson, Johanna W.; Teitelbaum, Samuel W.; Kandyla, Maria; Nelson, Keith A.

    2014-08-15

    We have developed a femtosecond single-shot spectroscopic technique to measure irreversible changes in condensed phase materials in real time. Crossed echelons generate a two-dimensional array of time-delayed pulses with one femtosecond probe pulse. This yields 9 ps of time-resolved data from a single laser shot, filling a gap in currently employed measurement methods. We can now monitor ultrafast irreversible dynamics in solid-state materials or other samples that cannot be flowed or replenished between laser shots, circumventing limitations of conventional pump-probe methods due to sample damage or product buildup. Despite the absence of signal-averaging in the single-shot measurement, an acceptable signal-to-noise level has been achieved via background and reference calibration procedures. Pump-induced changes in relative reflectivity as small as 0.2%−0.5% are demonstrated in semimetals, with both electronic and coherent phonon dynamics revealed by the data. The optical arrangement and the space-to-time conversion and calibration procedures necessary to achieve this level of operation are described. Sources of noise and approaches for dealing with them are discussed.

  11. SnapShot: The Bacterial Cytoskeleton.

    PubMed

    Fink, Gero; Szewczak-Harris, Andrzej; Löwe, Jan

    2016-07-14

    Most bacteria and archaea contain filamentous proteins and filament systems that are collectively known as the bacterial cytoskeleton, though not all of them are cytoskeletal, affect cell shape, or maintain intracellular organization. To view this SnapShot, open or download the PDF. PMID:27419875

  12. Dissipative hidden sector dark matter

    NASA Astrophysics Data System (ADS)

    Foot, R.; Vagnozzi, S.

    2015-01-01

    A simple way of explaining dark matter without modifying known Standard Model physics is to require the existence of a hidden (dark) sector, which interacts with the visible one predominantly via gravity. We consider a hidden sector containing two stable particles charged under an unbroken U (1 )' gauge symmetry, hence featuring dissipative interactions. The massless gauge field associated with this symmetry, the dark photon, can interact via kinetic mixing with the ordinary photon. In fact, such an interaction of strength ε ˜10-9 appears to be necessary in order to explain galactic structure. We calculate the effect of this new physics on big bang nucleosynthesis and its contribution to the relativistic energy density at hydrogen recombination. We then examine the process of dark recombination, during which neutral dark states are formed, which is important for large-scale structure formation. Galactic structure is considered next, focusing on spiral and irregular galaxies. For these galaxies we modeled the dark matter halo (at the current epoch) as a dissipative plasma of dark matter particles, where the energy lost due to dissipation is compensated by the energy produced from ordinary supernovae (the core-collapse energy is transferred to the hidden sector via kinetic mixing induced processes in the supernova core). We find that such a dynamical halo model can reproduce several observed features of disk galaxies, including the cored density profile and the Tully-Fisher relation. We also discuss how elliptical and dwarf spheroidal galaxies could fit into this picture. Finally, these analyses are combined to set bounds on the parameter space of our model, which can serve as a guideline for future experimental searches.

  13. Hidden variables: the resonance factor

    NASA Astrophysics Data System (ADS)

    Brooks, Juliana H. J.

    2009-08-01

    In 1900 Max Karl Planck performed his famous black-body radiation work which sparked the quantum revolution. Re-examination of that work has revealed hidden variables, consistent with Einstein's famous sentiment that quantum mechanics is incomplete due to the existence of "hidden variables". The recent discovery of these previously hidden variables, which have been missing from foundational equations for more than one hundred years, has important implications for theoretical, experimental and applied sciences and technologies. Planck attempted to integrate the new "resonant Hertzian (electromagnetic) waves", with existing Helmholtz theories on energy and thermodynamics. In his famous January 1901, paper on black-body radiation, Planck described two significant hypotheses - his well known Quantum Hypothesis, and his more obscure Resonance Hypothesis. Few scientists today are aware that Planck hypothesized resonant electromagnetic energy as a form of non-thermal energy available to perform work on a molecular basis, and that Planck's Resonance Hypothesis bridged the gap between classical Helmholtz energy state dynamics of the bulk macrostate, and energy state dynamics of the molecular microstate. Since the black-body experimental data involved only a thermal effect and not a resonant effect, Planck excluded the resonant state in his black-body derivation. He calculated Boltzmann's constant "kB" using completely thermal/entropic data, arriving at a value of 1.38 ×10-23 J K-1 per molecule, representing the internal energy of a molecule under completely thermal conditions. He further hypothesized, however, that if resonant energy was present in a system, the resonant energy would be "free to be converted into work". Planck seems to have been caught up in the events of the quantum revolution and never returned to his Resonance Hypothesis. As a result, a mathematical foundation for resonance dynamics was never completed. Boltzmann's constant was adopted into

  14. Quantum computation and hidden variables

    NASA Astrophysics Data System (ADS)

    Aristov, V. V.; Nikulov, A. V.

    2008-03-01

    Many physicists limit oneself to an instrumentalist description of quantum phenomena and ignore the problems of foundation and interpretation of quantum mechanics. This instrumentalist approach results to "specialization barbarism" and mass delusion concerning the problem, how a quantum computer can be made. The idea of quantum computation can be described within the limits of quantum formalism. But in order to understand how this idea can be put into practice one should realize the question: "What could the quantum formalism describe?", in spite of the absence of an universally recognized answer. Only a realization of this question and the undecided problem of quantum foundations allows to see in which quantum systems the superposition and EPR correlation could be expected. Because of the "specialization barbarism" many authors are sure that Bell proved full impossibility of any hidden-variables interpretation. Therefore it is important to emphasize that in reality Bell has restricted to validity limits of the no-hidden-variables proof and has shown that two-state quantum system can be described by hidden variables. The later means that no experimental result obtained on two-state quantum system can prove the existence of superposition and violation of the realism. One should not assume before unambiguous experimental evidence that any two-state quantum system is quantum bit. No experimental evidence of superposition of macroscopically distinct quantum states and of a quantum bit on base of superconductor structure was obtained for the present. Moreover same experimental results can not be described in the limits of the quantum formalism.

  15. Get Your Flu Shot!| NIH MedlinePlus the Magazine

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Flu Shot Get Your Flu Shot! Past Issues / Winter 2011 Table of Contents ... failure, or lung disease "For the 2010–2011 flu season, the flu vaccine provides protection against the ...

  16. Jello Shots While Underage, Bigger Booze Problems Later?

    MedlinePlus

    ... medlineplus/news/fullstory_158578.html Jello Shots While Underage, Bigger Booze Problems Later? Study suggests the alcohol- ... 2016 FRIDAY, April 29, 2016 (HealthDay News) -- Many underage Americans down jello shots, and these young drinkers ...

  17. 35. INTERIOR VIEW, WHEELBRATORFRYE SHOT PEENER FOR REMOVAL OF RUST ...

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

    35. INTERIOR VIEW, WHEELBRATOR-FRYE SHOT PEENER FOR REMOVAL OF RUST AND SCALE; NOTE TOOLS ARE TUMBLED WITH BLASTED WITH LEAD SHOT TO CLEAN SURFACES - Warwood Tool Company, Foot of Nineteenth Street, Wheeling, Ohio County, WV

  18. Flu Shot Safe for Surgery Patients in Hospital: Study

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_157754.html Flu Shot Safe for Surgery Patients in Hospital: Study ... increased risk for complications if they receive a flu shot in the hospital, a new study suggests. ...

  19. Unpolarized states and hidden polarization

    NASA Astrophysics Data System (ADS)

    de la Hoz, P.; Björk, G.; Klimov, A. B.; Leuchs, G.; Sánchez-Soto, L. L.

    2014-10-01

    We capitalize on a multipolar expansion of the polarization density matrix, in which multipoles appear as successive moments of the Stokes variables. When all the multipoles up to a given order K vanish, we can properly say that the state is Kth-order unpolarized, as it lacks of polarization information to that order. First-order unpolarized states coincide with the corresponding classical ones, whereas unpolarized to any order tally with the quantum notion of fully invariant states. In between these two extreme cases, there is a rich variety of situations that are explored here. The existence of hidden polarization emerges in a natural way in this context.

  20. Random graphs with hidden color.

    PubMed

    Söderberg, Bo

    2003-07-01

    We propose and investigate a unifying class of sparse random graph models, based on a hidden coloring of edge-vertex incidences, extending an existing approach, random graphs with a given degree distribution, in a way that admits a nontrivial correlation structure in the resulting graphs. The approach unifies a number of existing random graph ensembles within a common general formalism, and allows for the analytic calculation of observable graph characteristics. In particular, generating function techniques are used to derive the size distribution of connected components (clusters) as well as the location of the percolation threshold where a giant component appears. PMID:12935185

  1. Injury pattern of the Flash-Ball, a less-lethal weapon used for law enforcement: report of two cases and review of the literature.

    PubMed

    Wahl, Peter; Schreyer, Nicolas; Yersin, Bertrand

    2006-10-01

    Less-lethal weapons are used in law enforcement to neutralize combative individuals and to disperse riot crowds. Local police recently used such an impact weapon, the Flash-Ball, in two different situations. This gun fires large rubber bullets with kinetic energies around 200 J. Although it is designed to avoid skin penetration, impacts at such energies may still create major trauma with associated severe injuries to internal organs. This is a report of 2 patients shot with the Flash-Ball who required medical attention. One could be discharged quickly, but the other required hospitalization for heart and lung contusion. Both patients required advanced investigations including computed tomography (CT) scan. The medical literature on injuries induced by less-lethal impact weapons is reviewed. Impacts from the Flash-Ball can cause significant injury to internal organs, even without penetration. Investigations as for other high-energy blunt traumas are called for in these cases. PMID:16982375

  2. Shot to shot variation in perveance of the explosive emission electron beam diode

    SciTech Connect

    Roy, Amitava; Menon, R.; Singh, S. K.; Kulkarni, M. R.; Saroj, P. C.; Nagesh, K. V.; Mittal, K. C.; Chakravarthy, D. P.

    2009-03-15

    The shot to shot variation in perveance of a planar diode with explosive emission graphite cathode in a range of accelerating gaps 3-12 mm is investigated experimentally. The typical electron beam parameters were 200 kV, 12 kA, 100 ns, with a few hundreds of A/cm{sup 2} current density. The diode perveance remains less than the Child-Langmuir value, indicating that only a fraction of the cathode take part in the emission process. A simple statistical analysis of the diode perveance shows that the shot to shot variation is more pronounced for the later part of the accelerating pulse. The cathode plasma expansion velocity and the effective initial emission area have been calculated from the perveance data. It was found that the plasma expansion velocity varies from 3 to 6.5 cm/{mu}s. The mean expansion velocity and the standard deviation increase with the increase in the accelerating gap. The initial emission areas also varies randomly on a shot to shot basis and at the beginning of the accelerating pulse only 4%-35% of the cathode area take part in the emission process. The mean initial emission area and the standard deviation also increase with the increase in the accelerating gap. Experimental result indicates that the larger gaps and lower electric fields suggest a path to more uniform emission.

  3. 50 CFR 20.108 - Nontoxic shot zones.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Nontoxic shot zones. 20.108 Section 20.108... Nontoxic shot zones. Beginning September 1, 1991, the contiguous 48 United States, and the States of Alaska... United States, are designated for the purpose of § 20.21(j) as nontoxic shot zones for hunting...

  4. Ball to separator contact forces in angular contact ball bearings under thrust and radial loads

    NASA Technical Reports Server (NTRS)

    Nypan, L. J.

    1978-01-01

    Experimental data are reported on ball to cage contact forces in a 110 mm bore ball bearing operating at speeds to 12,000 rpm under radial and thrust loads. Information is also reported on cage to inner race land contact force, cage to inner race land clearance, and cage to shaft speed ratios.

  5. Dissolved gas - the hidden saboteur

    SciTech Connect

    Magorien, V.G.

    1993-12-31

    Almost all hydraulic power components, to properly perform their tasks, rely on one basic, physical property, i.e., the incompressibility of the working fluid. Unfortunately, a frequently overlooked fluid property which frustrates this requirement is its ability to absorb, i.e., dissolve, store and give off gas. The gas is, most often but not always, air. This property is a complex one because it is a function not only of the fluid`s chemical make-up but temperature, pressure, exposed area, depth and time. In its relationshiop to aircraft landing-gear, where energy is absorbed hydraulically, this multi-faceted fluid property can be detrimental in two ways: dynamically, i.e., loss of energy absorption ability and statically, i.e., improper aircraft attitude on the ground. The pupose of this paper is to bring an awareness to this property by presenting: (1) examples of these manifestations with some empirical and practical solutions to them, (2) illustrations of this normally `hidden saboteur` at work, (3) Henry`s Dissolved Gas Law, (4) room-temperature, saturated values of dissolved gas for a number of different working fluids, (5) a description of the instrument used to obtain them, (6) some `missing elements` of the Dissolved Gas Law pertaining to absoption, (7) how static and dynamic conditions effect gas absorption and (8) some recommended solutions to prevent becoming a victim of this `hidden saboteur`

  6. Hidden scale invariance of metals

    NASA Astrophysics Data System (ADS)

    Hummel, Felix; Kresse, Georg; Dyre, Jeppe C.; Pedersen, Ulf R.

    2015-11-01

    Density functional theory (DFT) calculations of 58 liquid elements at their triple point show that most metals exhibit near proportionality between the thermal fluctuations of the virial and the potential energy in the isochoric ensemble. This demonstrates a general "hidden" scale invariance of metals making the condensed part of the thermodynamic phase diagram effectively one dimensional with respect to structure and dynamics. DFT computed density scaling exponents, related to the Grüneisen parameter, are in good agreement with experimental values for the 16 elements where reliable data were available. Hidden scale invariance is demonstrated in detail for magnesium by showing invariance of structure and dynamics. Computed melting curves of period three metals follow curves with invariance (isomorphs). The experimental structure factor of magnesium is predicted by assuming scale invariant inverse power-law (IPL) pair interactions. However, crystal packings of several transition metals (V, Cr, Mn, Fe, Nb, Mo, Ta, W, and Hg), most post-transition metals (Ga, In, Sn, and Tl), and the metalloids Si and Ge cannot be explained by the IPL assumption. The virial-energy correlation coefficients of iron and phosphorous are shown to increase at elevated pressures. Finally, we discuss how scale invariance explains the Grüneisen equation of state and a number of well-known empirical melting and freezing rules.

  7. Building Simple Hidden Markov Models. Classroom Notes

    ERIC Educational Resources Information Center

    Ching, Wai-Ki; Ng, Michael K.

    2004-01-01

    Hidden Markov models (HMMs) are widely used in bioinformatics, speech recognition and many other areas. This note presents HMMs via the framework of classical Markov chain models. A simple example is given to illustrate the model. An estimation method for the transition probabilities of the hidden states is also discussed.

  8. Beyond Curriculum Reform: Confronting Medicine's Hidden Curriculum.

    ERIC Educational Resources Information Center

    Hafferty, Frederic W.

    1998-01-01

    Discusses the existence of three curricula in medical schools (formal, informal, and hidden) and suggests that educators and administrators investigate the hidden curriculum by examining four areas: institutional policies; evaluation practices; resource-allocation decisions; and institutional "slang." Needed reforms in accreditation standards are…

  9. Hidden Curriculum in Continuing Medical Education

    ERIC Educational Resources Information Center

    Bennett, Nancy; Lockyer, Jocelyn; Mann, Karen; Batty, Helen; LaForet, Karen; Rethans, Jan-Joost; Silver, Ivan

    2004-01-01

    In developing curricula for undergraduate and graduate medical education, educators have become increasingly aware of an interweaving of the formal, informal, and hidden curricula and their influences on the outcomes of teaching and learning. But, to date, there is little in the literature about the hidden curriculum of medical practice, which…

  10. Hidden Variable Theories and Quantum Nonlocality

    ERIC Educational Resources Information Center

    Boozer, A. D.

    2009-01-01

    We clarify the meaning of Bell's theorem and its implications for the construction of hidden variable theories by considering an example system consisting of two entangled spin-1/2 particles. Using this example, we present a simplified version of Bell's theorem and describe several hidden variable theories that agree with the predictions of…

  11. 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

  12. 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.

  13. Heating up the Galaxy with hidden photons

    SciTech Connect

    Dubovsky, Sergei; Hernández-Chifflet, Guzmán

    2015-12-29

    We elaborate on the dynamics of ionized interstellar medium in the presence of hidden photon dark matter. Our main focus is the ultra-light regime, where the hidden photon mass is smaller than the plasma frequency in the Milky Way. We point out that as a result of the Galactic plasma shielding direct detection of ultra-light photons in this mass range is especially challenging. However, we demonstrate that ultra-light hidden photon dark matter provides a powerful heating source for the ionized interstellar medium. This results in a strong bound on the kinetic mixing between hidden and regular photons all the way down to the hidden photon masses of order 10{sup −20} eV.

  14. Dark matter balls help supernovae to explode

    NASA Astrophysics Data System (ADS)

    Froggatt, C. D.; Nielsen, H. B.

    2015-10-01

    As a solution to the well-known problem that the shock wave potentially responsible for the explosion of a supernova actually tends to stall, we propose a new energy source arising from our model for dark matter. Our earlier model proposed that dark matter should consist of cm-large white dwarf-like objects kept together by a skin separating two different sorts of vacua. These dark matter balls or pearls will collect in the middle of any star throughout its lifetime. At some stage during the development of a supernova, the balls will begin to take in neutrons and then other surrounding material. By passing into a ball nucleons fall through a potential of order 10 MeV, causing a severe production of heat — of order 10 foe for a solar mass of material eaten by the balls. The temperature in the iron core will thereby be raised, splitting up the iron into smaller nuclei. This provides a mechanism for reviving the shock wave when it arrives and making the supernova explosion really occur. The onset of the heating due to the dark matter balls would at first stop the collapse of the supernova progenitor. This opens up the possibility of there being two collapses giving two neutrino outbursts, as apparently seen in the supernova SN1987A — one in Mont Blanc and one 4 h 43 min later in both IMB and Kamiokande.

  15. Silicon ball grid array chip carrier

    DOEpatents

    Palmer, David W.; Gassman, Richard A.; Chu, Dahwey

    2000-01-01

    A ball-grid-array integrated circuit (IC) chip carrier formed from a silicon substrate is disclosed. The silicon ball-grid-array chip carrier is of particular use with ICs having peripheral bond pads which can be reconfigured to a ball-grid-array. The use of a semiconductor substrate such as silicon for forming the ball-grid-array chip carrier allows the chip carrier to be fabricated on an IC process line with, at least in part, standard IC processes. Additionally, the silicon chip carrier can include components such as transistors, resistors, capacitors, inductors and sensors to form a "smart" chip carrier which can provide added functionality and testability to one or more ICs mounted on the chip carrier. Types of functionality that can be provided on the "smart" chip carrier include boundary-scan cells, built-in test structures, signal conditioning circuitry, power conditioning circuitry, and a reconfiguration capability. The "smart" chip carrier can also be used to form specialized or application-specific ICs (ASICs) from conventional ICs. Types of sensors that can be included on the silicon ball-grid-array chip carrier include temperature sensors, pressure sensors, stress sensors, inertia or acceleration sensors, and/or chemical sensors. These sensors can be fabricated by IC processes and can include microelectromechanical (MEM) devices.

  16. Histopathology of mallards dosed with lead and selected substitute shot

    USGS Publications Warehouse

    Locke, L.N.; Irby, H.D.; Bagley, G.E.

    1967-01-01

    The histopathological response of male game farm mallards fed lead, three types of plastic-coated lead, two lead-magnesium alloys, iron, copper, zinc-coated iron, and molybdenum-coated iron shot was studied. Mallards fed lead, plastic-coated lead, or lead-magnesium alloy shot developed a similar pathological response, including the formation of acid-fast intranuclear inclusion bodies in the kidneys. Birds fed iron or molybdenum-coated iron shot developed hemosiderosis of the liver. Two of four mallards fed zinc-coated iron shot also developed hemosiderosis of the liver. No lesions were found in mallards fed copper shot.

  17. VISTA Captures Celestial Cat's Hidden Secrets

    NASA Astrophysics Data System (ADS)

    2010-04-01

    few million years of life. VISTA's very wide field of view allows the whole star-forming region to be imaged in one shot with much greater clarity than ever before. The VISTA image is filled with countless stars of our Milky Way galaxy overlaid with spectacular tendrils of dark dust that are seen here fully for the first time. The dust is sufficiently thick in places to block even the near-infrared radiation to which VISTA's camera is sensitive. In many of the dusty areas, such as those close to the centre of the picture, features that appear orange are apparent - evidence of otherwise hidden active young stars and their accompanying jets. Further out though, slightly older stars are laid bare to VISTA's vision, revealing the processes taking them from their first nuclear fusion along the unsteady path of the first few million years of their lives. The VISTA telescope is now embarking on several big surveys of the southern sky that will take years to complete. The telescope's large mirror, high quality images, sensitive camera and huge field of view make it by far the most powerful infrared survey telescope on Earth. As this striking image shows, VISTA will keep astronomers busy analysing data they could not have otherwise acquired. This cat is out of the bag. More information ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites

  18. VISTA Captures Celestial Cat's Hidden Secrets

    NASA Astrophysics Data System (ADS)

    2010-04-01

    few million years of life. VISTA's very wide field of view allows the whole star-forming region to be imaged in one shot with much greater clarity than ever before. The VISTA image is filled with countless stars of our Milky Way galaxy overlaid with spectacular tendrils of dark dust that are seen here fully for the first time. The dust is sufficiently thick in places to block even the near-infrared radiation to which VISTA's camera is sensitive. In many of the dusty areas, such as those close to the centre of the picture, features that appear orange are apparent - evidence of otherwise hidden active young stars and their accompanying jets. Further out though, slightly older stars are laid bare to VISTA's vision, revealing the processes taking them from their first nuclear fusion along the unsteady path of the first few million years of their lives. The VISTA telescope is now embarking on several big surveys of the southern sky that will take years to complete. The telescope's large mirror, high quality images, sensitive camera and huge field of view make it by far the most powerful infrared survey telescope on Earth. As this striking image shows, VISTA will keep astronomers busy analysing data they could not have otherwise acquired. This cat is out of the bag. More information ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites

  19. Magnetized Target Fusion Integrated Engineering Test Shot

    NASA Astrophysics Data System (ADS)

    Intrator, T.; Sears, J.; Turchi, P. J.; Waganaar, W. J.; Weber, T.; Wurden, G. A.; Degnan, J. H.; Domonkos, M.; Grabowski, C.; Ruden, E. L.; White, W.; Gale, D.; Kostora, M.; Parker, J.; Frese, M. H.; Frese, S. D.; Camacho, J. F.; Coffey, S. K.; Makhin, V.; Siemon, R. E.; Fuelling, S.; Bauer, B. S.; Lynn, A. G.; Roderick, N. F.

    2010-11-01

    The LANL & AFRL collaboration has carried out the first engineering shakedown demonstration of a Magnetized Target Fusion (MTF) shot. We used a solid, cylinder aluminum flux compressor. The target plasma was created as a high density Field Reversed Configuration (FRC) with closed flux surfaces. After formation, the FRC was expelled to a compression region at 15km/sec. We show some initial data that characterize the target FRC, including some translation data from the Los Alamos FRC experiment FRXL and the FRCHX experiment at AFRL. Data from the implosion shot show that we achieved all our initial objectives. The solid liner realization of Magneto Inertial Fuson is only one of several magnetized, pulsed, fusion schemes that are being pursued.

  20. 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.

  1. Shot overlap model-based fracturing of curvilinear OPC layouts

    NASA Astrophysics Data System (ADS)

    Jiang, Shangliang; Zakhor, Avideh

    2014-10-01

    The semiconductor manufacturing industry has been continuously shrinking the critical dimension of integrated circuits. An important step in manufacturing integrated circuits is transforming the photomasks into constituent shots, a process referred to as fracturing. A major problem with fracturing is the explosion of shots which leads to long mask write times and costly masks. In this paper, we develop fracturing algorithms that are tailored towards curvilinear layouts, such as those optimized by pixel based OPC. Our proposed fracturing algorithms generate the location, size, and dosage of shots given the mask layout and mask manufacturing parameters. We propose two classes of algorithms that both allow for shot overlap. The first manhattanizes a curvilinear mask and applies our previously developed rectilinear fracturing algorithm upon the resulting rectilinear mask. The second one directly generates the shots by matching the boundary of the input polygon with a dictionary of possible shot corners that are associated with a shot dosage. This is followed by the same rectilinear fracturing algorithm to refine the shot edges. An important feature of all our algorithms is that they can readily trade off between mask error and shot count by adjusting input parameters. Compared to a commercially available non- overlapping shot software package, our algorithm results in up to a 50% reduction in shot count with comparable mask error.

  2. Centrifugal shot blasting. Innovative technology summary report

    SciTech Connect

    Not Available

    1999-07-01

    At the US Department of Energy (DOE) Fernald Environmental Management Project (FEMP), the Facilities Closure and Demolition Projects Integrated Remedial Design/Remedial Action (RD/RA) work plan calls for the removal of one inch (1 in) depth of concrete surface in areas where contamination with technetium-99 has been identified. This report describes a comparative demonstration between two concrete removal technologies: an innovative system using Centrifugal Shot Blasting (CSB) and a modified baseline technology called a rotary drum planer.

  3. SnapShot: Stress and Disease.

    PubMed

    Nagaraja, Archana S; Sadaoui, Nouara C; Dorniak, Piotr L; Lutgendorf, Susan K; Sood, Anil K

    2016-02-01

    Perturbation of an organism's homeostasis by stress can trigger biological or behavioral adaptation and accelerate onset and course of several diseases. Signaling triggered by norepinephrine or epinephrine (via adrenergic receptors) and cortisol (through glucocorticoid receptors) has profound effects on dampening immune responses, accelerating cancer progression and increasing the risk of cardiovascular, metabolic, and colonic diseases. To view this SnapShot, open or download the PDF. PMID:26863488

  4. SnapShot: Renal Cell Carcinoma.

    PubMed

    Ricketts, Christopher J; Crooks, Daniel R; Sourbier, Carole; Schmidt, Laura S; Srinivasan, Ramaprasad; Linehan, W Marston

    2016-04-11

    Renal cell carcinoma (RCC) is a heterogeneous disease made up of a number of different cancer types, with distinct histologies, clinical courses, therapeutic responses, and genetic drivers. Germline mutations in 14 genes have been associated with increased risk of RCC and can result in HIF pathway activation, chromatin dysregulation, and altered metabolism. Knowledge of these pathway alterations can inform the development of targeted therapeutic approaches. To view this SnapShot, open or download the PDF. PMID:27070709

  5. SnapShot: Neuronal Regulation of Aging.

    PubMed

    Weir, Heather J; Mair, William B

    2016-07-28

    Aging is characterized by loss of homeostasis across multiple tissues. The nervous system governs whole-body homeostasis by communicating external and internal signals to peripheral tissues. Here, we highlight neuronal mechanisms and downstream outputs that regulate aging and longevity. Targeting these neuronal pathways may be a novel strategy to promote healthy aging. To view this SnapShot, open or download the PDF. PMID:27471972

  6. Shot-time photography at the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Jedlovec, Donald; Christensen, Kim

    2015-08-01

    The Nation Ignition Facility (NIF) conducts a variety of experiments to study matter at the extremes, including studies of material properties, hydrodynamics, and the interaction of intense radiation fields with matter. The NIF supports the users by operating twenty-four hours a day, with a laser shot rate that averages one per day. We have developed a shot time camera that has the capability to provide an image of each shot for the users. While initially more of a promotional tool, there is emerging interest from the scientific staff in support of their experiments at the NIF. The shot time camera is a time integrated, shot-triggered, digital camera that images visible light generated at shot time in the NIF target chamber. It is selectable by the user and operates automatically with the NIF shot cycle. We will discuss the system design, recent results, and plans for the future.

  7. Hairy balls and flux lines in superconductors

    NASA Astrophysics Data System (ADS)

    Laver, Mark; Forgan, Ted

    2011-03-01

    Many physical phenomena originate from geometrical effects rather than from local physics. For example, the hairy ball theorem --- a hairy sphere cannot be combed --- is fulfilled by the atmospheric circulation with the existence of stratospheric polar vortices, and the fact that there is always at least one place on Earth where the horizontal wind is still. We examine the consequences of the hairy ball theorem for the flux line lattice (FLL). We find that discontinuities must exist in lattice shape as a function of field direction relative to the crystal. The remarkable ways in which the hairy ball theorem is fulfilled are demonstrated for FLL's in superconducting niobium. We show that extraordinary, unconventional flux line lattice shapes that spontaneously break the underlying crystal symmetry are surprisingly likely across all Type-II superconductors, both conventional and unconventional.

  8. Ball stud inspection system using machine vision.

    PubMed

    Shin, Dongik; Han, Changsoo; Moon, Young Shik

    2002-01-01

    In this paper, a vision-based inspection system that measures the dimensions of a ball stud is designed and implemented. The system acquires silhouetted images by backlighting and extracts the outlines of the nearly dichotomized images in subpixel accuracy. The sets of boundary data are modeled with reasonable geometric primitives and the parameters of the models are estimated in a manner that minimizes error. Jig-fixtures and servo systems for the inspection are also contrived. The system rotates an inspected object to recognize the objects in space not on a plane. The system moves the object vertically so that it may take several pictures of different parts of the object, resulting in improvement of measuring resolution. The performance of the system is evaluated by measurement of the dimensions of a standard ball, a standard cylinder, and a ball stud. PMID:12014800

  9. Relativistic-microwave theory of ball lightning

    PubMed Central

    Wu, H.-C.

    2016-01-01

    Ball lightning, a fireball sometimes observed during lightnings, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a lightning stroke reaching the ground, a relativistic electron bunch can be produced, which in turn excites intense microwave radiation. The latter ionizes the local air and the radiation pressure evacuates the resulting plasma, forming a spherical plasma bubble that stably traps the radiation. This mechanism is verified by particle simulations. The many known properties of ball lightning, such as the occurrence site, relation to the lightning channels, appearance in aircraft, its shape, size, sound, spark, spectrum, motion, as well as the resulting injuries and damages, are also explained. Our theory suggests that ball lighting can be created in the laboratory or triggered during thunderstorms. Our results should be useful for lightning protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics. PMID:27328835

  10. The bouncing ball through a geometrical series

    NASA Astrophysics Data System (ADS)

    Flores, Sergio; Alfaro, Luis L.; Chavez, Juan E.; Bastarrachea, Aztlan; Hurtado, Jazmin

    2008-10-01

    The mathematical representation of the physical situation related to a bouncing ball on the floor is an important understanding difficulty for most of the students during the introductory mechanics and mathematics courses. The research group named Physics and mathematics in context from the University of Ciudad Juarez is concerned about the versatility in the change from a mathematical representation to the own physical context of any problem under a traditional instruction. In this case, the main idea is the association of the physical properties of the bouncing ball situation to the nearest mathematical model based on a geometrical series. The proposal of the cognitive development is based on a geometrical series that shows the time the ball takes to stop. In addition, we show the behavior of the ratio of the consecutive heights during the motion.

  11. Relativistic-microwave theory of ball lightning

    NASA Astrophysics Data System (ADS)

    Wu, H.-C.

    2016-06-01

    Ball lightning, a fireball sometimes observed during lightnings, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a lightning stroke reaching the ground, a relativistic electron bunch can be produced, which in turn excites intense microwave radiation. The latter ionizes the local air and the radiation pressure evacuates the resulting plasma, forming a spherical plasma bubble that stably traps the radiation. This mechanism is verified by particle simulations. The many known properties of ball lightning, such as the occurrence site, relation to the lightning channels, appearance in aircraft, its shape, size, sound, spark, spectrum, motion, as well as the resulting injuries and damages, are also explained. Our theory suggests that ball lighting can be created in the laboratory or triggered during thunderstorms. Our results should be useful for lightning protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics.

  12. Relativistic-microwave theory of ball lightning.

    PubMed

    Wu, H-C

    2016-01-01

    Ball lightning, a fireball sometimes observed during lightnings, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a lightning stroke reaching the ground, a relativistic electron bunch can be produced, which in turn excites intense microwave radiation. The latter ionizes the local air and the radiation pressure evacuates the resulting plasma, forming a spherical plasma bubble that stably traps the radiation. This mechanism is verified by particle simulations. The many known properties of ball lightning, such as the occurrence site, relation to the lightning channels, appearance in aircraft, its shape, size, sound, spark, spectrum, motion, as well as the resulting injuries and damages, are also explained. Our theory suggests that ball lighting can be created in the laboratory or triggered during thunderstorms. Our results should be useful for lightning protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics. PMID:27328835

  13. Electrostatic charge bounds for ball lightning models

    NASA Astrophysics Data System (ADS)

    Stephan, Karl D.

    2008-03-01

    Several current theories concerning the nature of ball lightning predict a substantial electrostatic charge in order to account for its observed motion and shape (Turner 1998 Phys. Rep. 293 1; Abrahamson and Dinniss 2000 Nature 403 519). Using charged soap bubbles as a physical model for ball lightning, we show that the magnitude of charge predicted by some of these theories is too high to allow for the types of motion commonly observed in natural ball lightning, which includes horizontal motion above the ground and movement near grounded conductors. Experiments show that at charge levels of only 10-15 nC, 3-cm-diameter soap bubbles tend to be attracted by induced charges to the nearest grounded conductor and rupture. We conclude with a scaling rule that can be used to extrapolate these results to larger objects and surroundings.

  14. On the energy characteristics of ball lightning.

    PubMed

    Bychkov, A V; Bychkov, V L; Abrahamson, John

    2002-01-15

    A compilation of 17 observations of ball lightning showing the most energetic effects is presented along with estimates of their energy content. These observations were chosen from several thousand for the much stronger interaction of each ball lightning on its surroundings, and the method of energy estimation outlined. The case is put that some of the observations show a higher energy than self-contained chemical energy could provide. Comments have been added to the paper, arguing that the energy estimations themselves should be consistent with whatever model is used for ball lightning. For example, the presence of reacting nanoparticles releasing chemical energy may bring about the same observed effects with lower estimated energy. PMID:16210173

  15. Estimating shot distance from limited pellets pattern.

    PubMed

    Plebe, Alessio; Compagnini, Domenico

    2012-10-10

    Several methods are available for shooting range estimation based on pellets pattern on the target that have a remarkable degree of accuracy. The task is usually approached working under the assumption that the entire distribution of pellets is available for examination. These methods fail, however, when the victim has been hit by a portion of the pattern only. The problem can be solved with reasonable accuracy when there are areas of void in the victim that are adjacent to the area struck by pellets. This study presents a method that can be used in precisely this type of situation, allowing the estimation of shot distance in cases of partial pellet patterns. It is based on collecting distributions in test shots at several distances, and taking samples in the targets, constrained by the shape of the void and the pellet hit areas. Statistical descriptors of patterns are extracted from such samples, and fed into a neural network classifier, estimating shot ranges of distance. PMID:22658795

  16. Stochastic thermodynamics of hidden pumps

    NASA Astrophysics Data System (ADS)

    Esposito, Massimiliano; Parrondo, Juan M. R.

    2015-05-01

    We show that a reversible pumping mechanism operating between two states of a kinetic network can give rise to Poisson transitions between these two states. An external observer, for whom the pumping mechanism is not accessible, will observe a Markov chain satisfying local detailed balance with an emerging effective force induced by the hidden pump. Due to the reversibility of the pump, the actual entropy production turns out to be lower than the coarse-grained entropy production estimated from the flows and affinities of the resulting Markov chain. Moreover, in presence of a large time scale separation between the fast-pumping dynamics and the slow-network dynamics, a finite current with zero dissipation may be produced. We make use of these general results to build a synthetase-like kinetic scheme able to reversibly produce high free-energy molecules at a finite rate and a rotatory motor achieving 100% efficiency at finite speed.

  17. Stochastic thermodynamics of hidden pumps.

    PubMed

    Esposito, Massimiliano; Parrondo, Juan M R

    2015-05-01

    We show that a reversible pumping mechanism operating between two states of a kinetic network can give rise to Poisson transitions between these two states. An external observer, for whom the pumping mechanism is not accessible, will observe a Markov chain satisfying local detailed balance with an emerging effective force induced by the hidden pump. Due to the reversibility of the pump, the actual entropy production turns out to be lower than the coarse-grained entropy production estimated from the flows and affinities of the resulting Markov chain. Moreover, in presence of a large time scale separation between the fast-pumping dynamics and the slow-network dynamics, a finite current with zero dissipation may be produced. We make use of these general results to build a synthetase-like kinetic scheme able to reversibly produce high free-energy molecules at a finite rate and a rotatory motor achieving 100% efficiency at finite speed. PMID:26066126

  18. Drag Crisis of Gyro-Balls

    NASA Astrophysics Data System (ADS)

    Yokoyama, Yoshiyuki; Miyazaki, Takeshi; Himeno, Ryutaro

    2007-11-01

    Using a high-speed video camera, we measured the trajectory and the rotation of a hard baseball thrown by a pitching machine which can launch Gyro-Balls (rifle spinning balls). We determined the drag- and lift- coefficients by analyzing the video images. The measurements were performed in the range of 0.6x10^5ball with SP=0.12,0.23 and 0.35, decreases gradually with Re. However, the drag coefficient of a 2-seam gyro-ball with SP=0.12 decreases in two steps, i.e. in the ranges 0.8x10^5Ball with SP=0.23,0.35 are almost constant below Re=1.6x10^5 and Re=1.3x10^5, respectively. Their minima are attained at Re=1.8x10^5 and Re=1.6x10^5, respectively. These findings confirm the occurrence of the drag crisis for Gyro-Balls. The different Re-dependencies are due to the different seam patterns.

  19. Coulomb balls in Experiment and Simulation

    SciTech Connect

    Block, D.; Arp, O.; Piel, A.; Melzer, A.

    2005-10-31

    Recently, it was shown that it is possible to confine spherical dust clouds in a plasma. It was found that these dust clouds have a crystalline structure which differs notably from the well known fcc, bcc and hcp order in extended crystalline systems. The experiments show that the particles arrange in nested shells with hexagonal order on individual shells. The high transparency and the rather slow time scales of Coulomb balls allow to observe individual particles with video microscopy techniques and therefore to determine the structural properties of Coulomb balls with high accuracy. This contribution presents a comparison of experimental results and MD-Simulations.

  20. Soccer ball lift coefficients via trajectory analysis

    NASA Astrophysics Data System (ADS)

    Goff, John Eric; Carré, Matt J.

    2010-07-01

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.

  1. Variational Infinite Hidden Conditional Random Fields.

    PubMed

    Bousmalis, Konstantinos; Zafeiriou, Stefanos; Morency, Louis-Philippe; Pantic, Maja; Ghahramani, Zoubin

    2015-09-01

    Hidden conditional random fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An Infinite hidden conditional random field is a hidden conditional random field with a countably infinite number of hidden states, which rids us not only of the necessity to specify a priori a fixed number of hidden states available but also of the problem of overfitting. Markov chain Monte Carlo (MCMC) sampling algorithms are often employed for inference in such models. However, convergence of such algorithms is rather difficult to verify, and as the complexity of the task at hand increases the computational cost of such algorithms often becomes prohibitive. These limitations can be overcome by variational techniques. In this paper, we present a generalized framework for infinite HCRF models, and a novel variational inference approach on a model based on coupled Dirichlet Process Mixtures, the HCRF-DPM. We show that the variational HCRF-DPM is able to converge to a correct number of represented hidden states, and performs as well as the best parametric HCRFs-chosen via cross-validation-for the difficult tasks of recognizing instances of agreement, disagreement, and pain in audiovisual sequences. PMID:26353136

  2. Ball motion and sliding friction in an arched outer-race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1974-01-01

    The motion of the ball and sliding friction in an arched outer-race ball bearing under thrust load is analyzed. Fatigue life evaluations were made. The analysis is applied to a 150-millimeter-bore ball bearing. The results indicated that for high-speed light-load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be optimal. Also, for an arched bearing a considerable amount of spinning occurs at the outer-race contacts.

  3. Ball motion and sliding friction in an arched outer race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1973-01-01

    The motion of the ball and sliding friction in an arched outer race ball bearing under thrust loads is determined. Fatigue life evaluations were made. The analysis is applied to a 150 millimeter bore ball bearing. The results indicated that for high speed-light load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be an optimal. For an arched bearing it was also found that a considerable amount of spinning occurs at the outer race contacts.

  4. Ball motion and sliding friction in an arched outer race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1974-01-01

    The motion of the ball and sliding friction in an arched outer-race ball bearing under thrust load is determined. Fatigue life evaluations were made. The analysis is applied to a 150 millimeter bore ball bearing. The results indicated that for high speed-light load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be an optimal. For an arched bearing it was also found that a considerable amount of spinning occurs at the outer race contacts.

  5. Shallow velocity structure and hidden faults of Kunming city region

    NASA Astrophysics Data System (ADS)

    Yu, Geng-Xin; Lou, Hai; Wang, Chun-Yong; Fu, Li-Yun; Zhang, Jian-Guo; Qin, Jia-Zheng; Yang, Run-Hai; Li, Hai-Ou

    2008-09-01

    In order to image the 3-D velocity structure of its shallow crust in Kunming region, China, finite-difference seismic tomography is used to invert the seismic data selected carefully from six-shot data. The result lays a foundation for the discussion of the relationship between the obtained velocity structure and the hidden faults, and for the illumination of the depth extents of main active faults surrounding Kunming city. Puduhe-Xishan fault lies on the western margin of the Kunming basin and is just situated on the west edge of the low velocity anomaly zone found at all depth levels. This indicates that this fault is a borderline fault of the Kunming basin. It can be concluded that the fault dips eastwards with a steep angle and its depth extent is large. Puji-Hanjiacun fault and Heilongtan-Guandu fault play a role in controlling the low velocity anomaly zone in middle basin. The depth extents of the two faults are comparatively small, without traversing the interface of basin floor.

  6. The role of biomechanics in maximising distance and accuracy of golf shots.

    PubMed

    Hume, Patria A; Keogh, Justin; Reid, Duncan

    2005-01-01

    Golf biomechanics applies the principles and technique of mechanics to the structure and function of the golfer in an effort to improve golf technique and performance. A common recommendation for technical correction is maintaining a single fixed centre hub of rotation with a two-lever one-hinge moment arm to impart force on the ball. The primary and secondary spinal angles are important for conservation of angular momentum using the kinetic link principle to generate high club-head velocity. When the golfer wants to maximise the distance of their drives, relatively large ground reaction forces (GRF) need to be produced. However, during the backswing, a greater proportion of the GRF will be observed on the back foot, with transfer of the GRF on to the front foot during the downswing/acceleration phase. Rapidly stretching hip, trunk and upper limb muscles during the backswing, maximising the X-factor early in the downswing, and uncocking the wrists when the lead arm is about 30 degrees below the horizontal will take advantage of the summation of force principle. This will help generate large angular velocity of the club head, and ultimately ball displacement. Physical conditioning will help to recruit the muscles in the correct sequence and to optimum effect. To maximise the accuracy of chipping and putting shots, the golfer should produce a lower grip on the club and a slower/shorter backswing. Consistent patterns of shoulder and wrist movements and temporal patterning result in successful chip shots. Qualitative and quantitative methods are used to biomechanically assess golf techniques. Two- and three-dimensional videography, force plate analysis and electromyography techniques have been employed. The common golf biomechanics principles necessary to understand golf technique are stability, Newton's laws of motion (inertia, acceleration, action reaction), lever arms, conservation of angular momentum, projectiles, the kinetic link principle and the stretch

  7. Calibration of industrial CT using two forest-balls

    NASA Astrophysics Data System (ADS)

    Shi, Yushu; Song, Xu; Li, Shi; Li, Wei; Li, Qi; Chen, Siwen; Shen, Fei; Song, Xiaoping; Gao, Sitian

    2015-02-01

    A small forest-ball was manufactured and calibrated using CMM F25. An industrial CT called Metrotom1500 was calibrated by the small forest-ball and another big forest-ball produced by Carl Zeiss. These two forest-balls were separately measured at two different magnifications of the industrial CT, and the measurement results could meet the maximum permissible error of Metrotom1500.

  8. 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.

  9. Heat-balling wasps by honeybees

    NASA Astrophysics Data System (ADS)

    Ken, Tan; Hepburn, H. R.; Radloff, S. E.; Yusheng, Yu; Yiqiu, Liu; Danyin, Zhou; Neumann, P.

    2005-10-01

    Defensiveness of honeybee colonies of Apis cerana and Apis mellifera (actively balling the wasps but reduction of foraging) against predatory wasps, Vespa velutina, and false wasps was assessed. There were significantly more worker bees in balls of the former than latter. Core temperatures in a ball around a live wasp of A. cerana were significantly higher than those of A. mellifera, and also significantly more when exposed to false wasps. Core temperatures of bee balls exposed to false wasps were significantly lower than those exposed to V. velutina for both A. cerana and for A. mellifera. The lethal thermal limits for V. velutina, A. cerana and A. mellifera were significantly different, so that both species of honeybees have a thermal safety factor in heat-killing such wasp predators. During wasps attacks at the hives measured at 3, 6 and 12 min, the numbers of Apis cerana cerana and Apis cerana indica bees continuing to forage were significantly reduced with increased wasp attack time. Tropical lowland A. c. indica reduced foraging rates significantly more than the highland A. c. cerana bees; but, there was no significant effect on foraging by A. mellifera. The latency to recovery of honeybee foraging was significantly greater the longer the duration of wasp attacks. The results show remarkable thermal fine-tuning in a co-evolving predator prey relationship.

  10. Sharpening ball-nose mill cutters

    NASA Technical Reports Server (NTRS)

    Burch, C. F.

    1977-01-01

    Economical attachment allows faster, more precise grinding. Vibrationless and rigid relation between grinding wheel and cutter allows for extremely high finish and accurate grinding. Leveling device levels flutes with respect to toolholder rotation that generates ball-nose radius. Constant relief around entire profile of cutting edge produces longer tool life.

  11. Ball and Roller Bearings. A Teaching Reference.

    ERIC Educational Resources Information Center

    American Association for Vocational Instructional Materials, Athens, GA.

    The manual provides a subject reference for ball and roller bearings. The following topics are included: (1) bearing nomenclature, (2) bearing uses, (3) bearing capacities, (4) shop area working conditions, (5) bearing removal, (6) bearing cleaning and inspection, (7) bearing replacement, (8) bearing lubrication, (9) bearing installation, (10)…

  12. When Two Balls Are Just One

    ERIC Educational Resources Information Center

    Kulp, Christopher W.; Biermann, Mark L.; Howard, Timothy; Klingenberg, Kurtis; Ramsey, Paul

    2008-01-01

    A camcorder can be a powerful tool in pedagogical settings, such as in an introductory physics course or in introducing undergraduates to data collection. In this paper, we discuss our experience using a Panasonic PV-GS150 digital camcorder to analyze the motion of a falling steel ball, with the goal of determining the acceleration due to gravity,…

  13. 4. pi. physics with the plastic ball

    SciTech Connect

    Gutbrod, H.H.; Loehner, H.; Poskanzer, A.M.; Renner, T.; Riedesel, H.; Ritter, H.G.; Warwick, A.; Weik, F.; Wieman, H.

    1982-10-01

    4 ..pi.. data taken with the Plastic Ball show that cluster production in relativistic nuclear collisions depends on both the size of the participant volume and the finite size of the cluster. The measurement of the degree of thermalization and the search for collective flow will permit the study of the applicability of macroscopic concepts such as temperature and density.

  14. Construction of the noncommutative complex ball

    SciTech Connect

    Wang, Zhituo

    2014-09-15

    We describe the construction of the noncommutative complex ball whose commutative analog is the Hermitian symmetric space D = SU(m, 1)/U(m), with the method of coherent state quantization. In the commutative limit, we obtain the standard manifold. We also consider a quantum field theory model on the noncommutative manifold.

  15. Intelligent monitoring of ball bearing conditions

    NASA Astrophysics Data System (ADS)

    Liu, T. I.; Mengel, J. M.

    1992-09-01

    Ball bearings are widely used in various kinds of robots, manufacturing machines, and equipment. In order to enhance productivity and improve product quality, an on-line monitoring system is essential to check the status of ball bearings. In this work, peak amplitude in the frequency domain, peak RMS, and the power spectrum were used as indirect indices to develop a system for monitoring and classifying ball bearing defects. These indices were then processed by artificial neural networks. Six different cases of ball bearing states were observed. The data from these observations were then input into neural networks with different architectures to train these neural networks in a learning process. All the trained neural networks are capable of distinguishing the normal bearings from defective bearings with a 100 percent success rate. They can also classify the bearing conditions into six different states with a success rate of up to 97 per cent. The effects of training set sizes and neural network structures on the monitoring performance have also been investigated.

  16. Improvements In Ball-Screw Linear Actuators

    NASA Technical Reports Server (NTRS)

    Iskenderian, Theodore; Joffe, Benjamin; Summers, Robert

    1996-01-01

    Report describes modifications of design of type of ball-screw linear actuator driven by dc motor, with linear-displacement feedback via linear variable-differential transformer (LVDT). Actuators used to position spacecraft engines to direct thrust. Modifications directed toward ensuring reliable and predictable operation during planned 12-year cruise and interval of hard use at end of cruise.

  17. The Ball Aptitude Battery (Test Review).

    ERIC Educational Resources Information Center

    Hall, Alfred E.

    1985-01-01

    The 12 subtests of the Ball Aptitude Battery (BAB) listed in the administration manual were described. The reviewer believes this aptitude battery, designed for use with high school students and adults in job selection and placement, needs major improvements. It is suggested that the BAB be used solely for research purposes. (DWH)

  18. The Ball Bearing as a Motor.

    ERIC Educational Resources Information Center

    Gruenberg, H.

    1978-01-01

    Develops a theory to explain the effect that, when a current passes through a ball bearing, it can act as a motor. The motor can run in either direction on both DC and AC and can be self-starting on DC. Presents some experimental results in support of the theory. (Author/GA)

  19. Fractal Aggregates in Tennis Ball Systems

    ERIC Educational Resources Information Center

    Sabin, J.; Bandin, M.; Prieto, G.; Sarmiento, F.

    2009-01-01

    We present a new practical exercise to explain the mechanisms of aggregation of some colloids which are otherwise not easy to understand. We have used tennis balls to simulate, in a visual way, the aggregation of colloids under reaction-limited colloid aggregation (RLCA) and diffusion-limited colloid aggregation (DLCA) regimes. We have used the…

  20. The dynamic behavior of squash balls

    NASA Astrophysics Data System (ADS)

    Lewis, Gareth J.; Arnold, J. Cris; Griffiths, Iwan W.

    2011-03-01

    The behavior of a squash ball constitutes an excellent case study of the dynamic behavior of rubbery materials. It is shown that the complex viscoelastic behavior of rubber can be investigated using simple drop bounce tests and compression tests. The drop tests show that the coefficient of restitution increases as the ball temperature increases. The compression tests show that as the speed of compression increases or as the ball temperature decreases, the compressive force and the energy loss both increase. These effects are due to the viscoelastic nature of the rubber and are an excellent example of the time-temperature equivalence of polymers. Compression tests were performed on balls with small holes at the base to separate the effects of the internal air pressure from the material deformation. It was found that the internal air pressure contributed about one-third to the compressive force, but contributed little to energy loss. This behavior shows that the rubber material dominates the rebound behavior and that the normal warming up process at the start of a squash game is important to raise the temperature of the rubber rather than to increase the internal air pressure.

  1. Computed Tomography Analysis of NASA BSTRA Balls

    SciTech Connect

    Perry, R L; Schneberk, D J; Thompson, R R

    2004-10-12

    Fifteen 1.25 inch BSTRA balls were scanned with the high energy computed tomography system at LLNL. This system has a resolution limit of approximately 210 microns. A threshold of 238 microns (two voxels) was used, and no anomalies at or greater than this were observed.

  2. Stereoscopic Investigations of 3D Coulomb Balls

    SciTech Connect

    Kaeding, Sebastian; Melzer, Andre; Arp, Oliver; Block, Dietmar; Piel, Alexander

    2005-10-31

    In dusty plasmas particles are arranged due to the influence of external forces and the Coulomb interaction. Recently Arp et al. were able to generate 3D spherical dust clouds, so-called Coulomb balls. Here, we present measurements that reveal the full 3D particle trajectories from stereoscopic imaging.

  3. Supersymmetric Q-balls: A numerical study

    SciTech Connect

    Campanelli, L.; Ruggieri, M.

    2008-02-15

    We study numerically a class of nontopological solitons, the Q-balls, arising in a supersymmetric extension of the standard model with low-energy, gauge-mediated symmetry breaking. Taking into account the exact form of the supersymmetric potential giving rise to Q-balls, we find that there is a lower limit on the value of the charge Q in order to make them classically stable: Q > or approx. 5x10{sup 2}Q{sub cr}, where Q{sub cr} is constant depending on the parameters defining the potential and can be in the range 1 < or approx. Q{sub cr} < or approx. 10{sup 8} {sup divide} {sup 16}. If Q is the baryon number, stability with respect to the decay into protons requires Q > or approx. 10{sup 17}Q{sub cr}, while if the gravitino mass is greater then m{sub 3/2} > or approx. 61 MeV, no stable gauge-mediation supersymmetric Q-balls exist. Finally, we find that energy and radius of Q-balls can be parametrized as E{approx}{xi}{sub E}Q{sup 3/4} and R{approx}{xi}{sub R}Q{sup 1/4}, where {xi}{sub E} and {xi}{sub R} are slowly varying functions of the charge.

  4. Spherical polytropic balls cannot mimic black holes

    NASA Astrophysics Data System (ADS)

    Saida, Hiromi; Fujisawa, Atsuhito; Yoo, Chul-Moon; Nambu, Yasusada

    2016-04-01

    The so-called black hole shadow is a dark region which is expected to appear in a fine image of optical observation of black holes. It is essentially an absorption cross section of the black hole, and the boundary of shadow is determined by unstable circular orbits of photons (UCOP). If there exists a compact object possessing UCOP but no black hole horizon, it can provide us with the same shadow image as black holes, and detection of a shadow image cannot be direct evidence of black hole existence. This paper examines whether or not such compact objects can exist under some suitable conditions. We investigate thoroughly the static spherical polytropic ball of perfect fluid with single polytrope index, and then investigate a representative example of a piecewise polytropic ball. Our result is that the spherical polytropic ball which we have investigated cannot possess UCOP, if the speed of sound at the center is subluminal (slower than light). This means that, if the polytrope treated in this paper is a good model of stellar matter in compact objects, the detection of a shadow image can be regarded as good evidence of black hole existence. As a by-product, we have found the upper bound of the mass-to-radius ratio of a polytropic ball with single index, M_{ast }/R_{ast } < 0.281, under the condition of subluminal sound speed.

  5. Introducing a High Bounce Ball Unit

    ERIC Educational Resources Information Center

    Bernardo, Pat

    2004-01-01

    Those growing up in the 1950s, 60s or 70s are familiar with how physically active children were before computers and video games were introduced. Each neighborhood had its own version of the various games that were played. Many of these games involved a pink rubber ball called a Spaldeen. They were everywhere and almost everyone had one. These…

  6. Exploring the Mathematics of Bouncing Balls

    ERIC Educational Resources Information Center

    Vinogradova, Natalya; Blaine, Larry G.

    2010-01-01

    A common textbook problem asks students to calculate the total distance traveled by a bouncing ball, from its initial release until it comes to rest, under the assumption that the height of each bounce is some fixed proportion "r" of the height of the previous bounce. The solution is found by inserting information about "r" and the height from…

  7. Measuring the Rebound Resilience of a Bouncing Ball

    ERIC Educational Resources Information Center

    Wadhwa, Ajay

    2012-01-01

    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…

  8. Interrelation between ball lightning and optically induced forces

    NASA Astrophysics Data System (ADS)

    Torchigin, V. P.; Torchigin, A. V.

    2013-09-01

    Optically induced forces are considered as a key factor for explaining the phenomenon of ball lightning. They can provide not only the existence of ball lightning in the form of self-confined intense white light circulating in a spherical shell of air strongly compressed by the light but also the anomalous motion of ball lightning in the terrestrial atmosphere.

  9. Validity and Reliability of a Medicine Ball Explosive Power Test.

    ERIC Educational Resources Information Center

    Stockbrugger, Barry A.; Haennel, Robert G.

    2001-01-01

    Evaluated the validity and reliability of a medicine ball throw test to evaluate explosive power. Data on competitive sand volleyball players who performed a medicine ball throw and a standard countermovement jump indicated that the medicine ball throw test was a valid and reliable way to assess explosive power for an analogous total-body movement…

  10. METHODOLOGICAL NOTES: Energy density calculations for ball-lightning-like luminous silicon balls

    NASA Astrophysics Data System (ADS)

    Paiva, Gerson S.; Ferreira, Joacy V.; Bastos, Cristiano C.; dos Santos, Marcus V.; Pavão, Antonio C.

    2010-05-01

    The energy density of a luminous silicon ball [Phys. Rev. Lett. 98 048501 (2007)] is calculated for a model with a metal core surrounded by an atmosphere of silicon oxides. Experimental data combined with the molecular orbital calculations of the oxidation enthalpy lead to a mean energy density of 3.9 MJ m-3, which is within the range of estimates from other ball lightning models. This result provides good evidence to support the silicon-based model.

  11. Perspective: Disclosing hidden sources of funding.

    PubMed

    Resnik, David B

    2009-09-01

    In this article, the author discusses ethical and policy issues related to the disclosure of hidden sources of funding in research. The author argues that authors have an ethical obligation to disclose hidden sources of funding and that journals should adopt policies to enforce this obligation. Journal policies should require disclosure of hidden sources of funding that authors know about and that have a direct relation to their research. To stimulate this discussion, the author describes a recent case: investigators who conducted a lung cancer screening study had received funding from a private foundation that was supported by a tobacco company, but they did not disclose this relationship to the journal. Investigators and journal editors must be prepared to deal with these issues in a manner that promotes honesty, transparency, fairness, and accountability in research. The development of well-defined, reasonable policies pertaining to hidden sources of funding can be a step in this direction. PMID:19707061

  12. Fibroid Tumors in Women: A Hidden Epidemic?

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Fibroid Tumors in Women: A Hidden Epidemic? Past Issues / ... risk for a woman to develop tumors." Got Fibroids? Volunteers Wanted: Sisters Who Have (Or Have Had) ...

  13. Disposition of weapon-grade plutonium with pebble bed type HTGRs using Pu burner balls and Th breeder balls

    SciTech Connect

    Yamashita, Kiyonobu; Tokuhara, Kazumi; Fujimoto, Nozomu; Kunitomi, Kazuhiko

    1996-08-01

    A concept of reactor system was developed with which weapons-grade plutonium could be made perfectly worthless in use for weapons. It is a pebble bed type HTGR using Pu burner ball fuels and Th breeder ball fuels. The residual amounts of {sup 239}Pu in spent Pu balls become less than 1% of the initial loading. Furthermore, a method was found that the power coefficient could be made negative by heavy Pu loading in the Pu burner ball fuels.

  14. 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.

  15. Concrete Cleaning, Inc. centrifugal shot blaster: Baseline report; Summary

    SciTech Connect

    1997-07-31

    The centrifugal shot blaster is an electronically operated shot-blast machine that removes layer of concrete of varying depths. Hardened steel shot propelled at a high rate of speed abrades the surface of the concrete. The depth of material removed is determined by the rate of speed the machine is traveling and the volume of shot being fired into the blast chamber. The steel shot is reused until it is pulverized to dust, which is deposited in the waste container with the concrete being removed. Debris is continually vacuumed by a large dust collection system attached to the shot blaster. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

  16. Influence of Running on Pistol Shot Hit Patterns.

    PubMed

    Kerkhoff, Wim; Bolck, Annabel; Mattijssen, Erwin J A T

    2016-01-01

    In shooting scene reconstructions, risk assessment of the situation can be important for the legal system. Shooting accuracy and precision, and thus risk assessment, might be correlated with the shooter's physical movement and experience. The hit patterns of inexperienced and experienced shooters, while shooting stationary (10 shots) and in running motion (10 shots) with a semi-automatic pistol, were compared visually (with confidence ellipses) and statistically. The results show a significant difference in precision (circumference of the hit patterns) between stationary shots and shots fired in motion for both inexperienced and experienced shooters. The decrease in precision for all shooters was significantly larger in the y-direction than in the x-direction. The precision of the experienced shooters is overall better than that of the inexperienced shooters. No significant change in accuracy (shift in the hit pattern center) between stationary shots and shots fired in motion can be seen for all shooters. PMID:26331462

  17. Settlement rate of lead shot in tundra wetlands

    USGS Publications Warehouse

    Flint, P.L.

    1998-01-01

    Several species of breeding waterfowl have been shown to be exposed to lead shot on the Yukon-Kuskokwim (Y-K) Delta, Alaska. I 'seeded' experimental plots with number 4 lead shot to determine the settlement rate of shot in wetland types commonly used by foraging waterfowl. I resampled plots for 3 years, using a suction dredge to remove sediment in 4-cm layers. There was no consistent change in the proportion of shot recovered in the 0-4-cm layer among years or habitat types. My results suggest lead shot is available to feeding waterfowl for many years, and that exposure of waterfowl to lead poisoning will likely occur for >3 years after the use of lead shot is curtailed.

  18. Harmonic demodulation of nonstationary shot noise.

    PubMed

    Gray, M B; Stevenson, A J; Bachor, H A; McClelland, D E

    1993-05-15

    We report on experimental demodulation of nonstationary shot noise, which is associated with strongly modulated light. For sinusoidal modulation and demodulation, measurements confirm theoretical predictions of 1.8-dB excess noise in the modulation quadrature and 3-dB noise reduction in the opposite quadrature, relative to the standard quantum limit. Demodulation with a third harmonic produces noise correlated with that which is due to the fundamental. Reducing excess noise by 0.8 dB in the modulation quadrature, by combining the fundamental and third harmonics in a 2:1 ratio, is shown to be feasible. PMID:19802263

  19. [Forensic medical characteristics of Glock 19 pistol-shot wounds].

    PubMed

    Musin, E Kh; Lepik, D; Viali, M

    2006-01-01

    An experimental study was made of gun-shot wounds inflicted by shots from a modern stub-barrelled pistol 9mm Glock 19. The study has ascertain characteristics differentiating injuries inflicted by shots from this pistol: specific recoil injury, specific topography, intensity and distribution of begrime, gunpowder and metal particles and relevant lesions. It was found that depth of penetration under the skin depends both on shooting distance and the position of the particle from the inlet. PMID:16509203

  20. Hematologic comparisons of shot and live trapped cottontail rabbits.

    PubMed

    Jacobson, H A; Kirkpatrick, R L; Burkhart, H E; Davis, J W

    1978-01-01

    Comparisons were made between hematologic measurements of shot and box-trapped cottontail rabbits (Sylvilagus floridanus). Trapped rabbits had significantly (P less than 0.001) higher serum corticoid levels and segmented neutrophil percentages and significantly (P less than 0.001) lower lymphocyte percentages than did shot rabbits. Trapped rabbits also had significantly (P less than 0.05) higher packed cell volumes and blood urea nitrogen values than did shot rabbits. PMID:633520

  1. Corrosion potential of steel bird shot in dogs.

    PubMed

    Bartels, K E; Stair, E L; Cohen, R E

    1991-10-01

    Each year many dogs are accidentally or purposely wounded with shotguns. When lead pellets were used exclusively in the past, clinical problems from chronically embedded shot seldom developed except for rare cases of lead toxicosis. However, because expended lead shot ingested unintentionally by waterfowl and other avian species is fatal, the US Fish and Wildlife Service mandated exclusive use of steel shot for waterfowl hunting beginning in 1991. To discover the effects of implanted steel shot in a biological system, in vitro and in vivo studies were performed. Severe surface corrosion was evident when steel shot was placed in physiologic saline solution and sterile canine plasma. Eight laboratory dogs were surgically implanted with sterile steel shot in various superficial locations for intervals of 2 to 26 weeks. Corrosion of implants and tissue inflammation was observed in all biopsy specimens examined. It has been shown that steel shot embedded in tissues will corrode and result in a severe inflammatory response. If the accompanying inflammation is complicated by bacterial contamination, foreign body reactions resulting in infected, draining tracts could develop. Veterinarians and dog owners should be aware that treatment and prognosis for wounds caused by steel shot may differ from those for similar wounds caused by lead shot. PMID:1769870

  2. Expected spectrum of high-energy photons from ball lightning

    NASA Astrophysics Data System (ADS)

    Shmatov, M. L.

    2006-04-01

    Two methods for identifying the flux of high-energy photons as emitted by ball lightning are proposed. It is assumed that ball lightning has a core consisting of oscillating clouds of electrons and totally ionized ions. A search for tooth enamel changes due to the influence of high-energy photons from ball lightning to reveal the influence of such photons on human beings is also proposed. This diagnostic measure should be taken if after observation of ball lightning symptoms similar to those of radiation sickness arise or ball lightning causes heavy burns.

  3. Cue and ball deflection (or ``squirt'') in billiards

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2008-03-01

    A billiard ball struck by a cue travels in the same direction as the cue unless the ball is struck toward one side in order to impart sidespin. In that case the ball deflects or "squirts" away from the line of approach of the cue, typically by a few degrees. Measurements and calculations are presented showing how a cue tip slides across the ball if it is unchalked, resulting in a large squirt angle, and how it grips the ball when it is chalked, resulting in a smaller squirt angle.

  4. Sitting on stability balls: biomechanics evaluation in a workplace setting.

    PubMed

    Schult, Tamara M; Awosika, Ebi R; Schmunk, Sandra K; Hodgson, Michael J; Heymach, Bria L; Parker, Celestine Dent

    2013-01-01

    Use of a stability ball alone and stability ball chair were evaluated in the Veterans Health Administration as possible alternatives to incorporate with regular office chair use. The evaluation of stability ball use was conducted under the auspices of a work site health promotion program as a cross-over trial with participants rotating through use of the stability ball, stability ball chair, and regular office chair on a monthly basis for a total duration of 3 months. Rotations on regular office chairs served as the control. Three medical facilities participated. A total of 193 employees completed a baseline questionnaire; 159 completed at least one post-rotation questionnaire. Self-reported measures included perceived posture when sitting, perceptions of overall balance, energy levels, job performance, safety, and pain. Use was associated with improvements in perceived posture (p < 0.0001) and energy levels (p = 0.007) for stability ball users compared with the office chair control, and improvements in perceived posture (p < 0.0001) and overall balance (p = 0.05) for stability ball chair users compared with the control. Use of stability balls at work decreases the likelihood of reporting pain from regular office chair use from approximately 45% to 21%. Alternatively, a high number of participants reported pain with use of the stability ball alone and stability ball chair, 42% and 45%, respectively. The perceived risks and benefits of stability ball use should be weighed when incorporating use. PMID:23252582

  5. 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.

  6. 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.

  7. High-precision silicon nitride balls for bearings

    NASA Astrophysics Data System (ADS)

    Cundill, Robin T.

    1992-04-01

    Hybrid ceramic bearings are now commercially available for use in high performance applications where the properties of the ceramic balls give advantages in terms of higher operating speeds, increased stiffness, lower fraction and less heat generation. Most hybrid bearings are high precision angular contact ball bearings fitted with silicon nitride balls, which have to be finished to ISO dimensional grades 3 and 5. Ball diameter variation and deviation from the spherical form has to be less than 0.125 micrometers for Grade 5 balls and less than 0.08 micrometers for Grade 3 balls. Surface finish of silicon nitride balls is typically 0.003 - 0.010 micrometers Rq (0.002 - 0.008 micrometers Ra). At this level, the basic material microstructures is discernible which facilitates inspection for material and other faults.

  8. The effects of ball size distribution on attritor efficiency

    SciTech Connect

    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.

  9. The strange flight behaviour of slowly spinning soccer balls

    PubMed Central

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

    2013-01-01

    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. PMID:23695000

  10. New hidden beauty molecules predicted by the local hidden gauge approach and heavy quark spin symmetry

    NASA Astrophysics Data System (ADS)

    Xiao, C. W.; Ozpineci, A.; Oset, E.

    2015-10-01

    Using a coupled channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-meson interaction with hidden beauty. We obtain several new states of isospin I = 0: six bound states, and weakly bound six more possible states which depend on the influence of the coupled channel effects.

  11. Joining of Thin Metal Sheets by Shot Peening

    NASA Astrophysics Data System (ADS)

    Harada, Yasunori

    2011-01-01

    In shot peening the substrate undergoes large plastic deformation near the surface due to the hit with shots. The plastic flow areas formed by cold working may form the surface layer. Authors have recently proposed new joining methods using shot peening, shot lining and shot caulking. Our approach has been applied to the butt joining of the dissimilar metal sheets. In the present study, joining of thin metal sheets using a shot peening process was investigated to improve the joinability. In the joined section, the edge of sheets is the equally-spaced slits. In this method, the convex edges of the sheet are laid on top of the other sheet. Namely, the two sheets are superimposed in the joining area. When the connection is shot-peened, the material of the convex area undergoes large plastic deformation near the surface due to the collision of shots. In this process, particularly noteworthy is the plastic flow near surface layer. The convex edges of the sheet can be joined to the other sheet, thus two sheets are joined each other. In the experiment, the shot peening treatment was performed by using an air-type peening machine. The shots used were made of high carbon cast steel. Air pressure was 0.6 MPa and peening time was in the range of 30-150s. The peening conditions were controlled in the experiment. The thin sheets were commercial low-carbon steel, stainless steel, pure aluminum, and aluminium alloy. The effects of processing conditions on the joinability were mainly examined. The joint strength increased with the kinetic energy of shots. It was found that the present method was effective for joining of thin metal sheets.

  12. The squint Moon and the witch ball

    NASA Astrophysics Data System (ADS)

    Berry, M. V.

    2015-06-01

    A witch ball is a reflecting sphere of glass. Looking into the disk that it subtends, the whole sky can be seen at one glance. This feature can be exploited to see and photograph the squint Moon illusion, in which the direction normal to the illuminated face of the Moon—its ‘attitude vector’—does not appear to point towards the Sun. The images of the Sun and Moon in the disk, the geodesic connecting them, the Moon’s attitude, and the squint angle (distinct from the tilt), can be calculated and simulated, for all celestial configurations and viewing inclinations. The Moon direction antipodal to the Sun, corresponding to full Moon, is a singularity of the attitude vector field, with index +1. The main features of the witch ball images also occur in other ways of imaging the squint Moon.

  13. Instrumented drop ball tester for percussion primers

    SciTech Connect

    Woods, C.M.; Robinson, M.A.; Merten, C.W.; Robbins, V.E. ); Begeal, D.R. )

    1991-01-01

    The drop ball tester has historically been used for determining the threshold characteristics of percussion primers. Typically, the data obtained from such a tester show a wide variation with significantly large standard deviations. This requires that the acceptance specifications for primers be fairly lax. To determine how much of the data scatter was due to the tester alone, a drop ball tester was instrumented with a force monitoring gage, velocity capabilities, deflection gages, and a pressure time output measuring system. This paper deals with the basic fundamental physics involved with the tester and presents results of improvements to the tester geometry. Threshold test results are presented, correlating all of the variables measured. 8 refs., 10 figs.

  14. Irregular diffusion in the bouncing ball billiard

    NASA Astrophysics Data System (ADS)

    Mátyás, L.; Klages, R.

    2004-01-01

    We call a system bouncing ball billiard if it consists of a particle that is subject to a constant vertical force and bounces inelastically on a one-dimensional vibrating periodically corrugated floor. Here we choose circular scatterers that are very shallow, hence this billiard is a deterministic diffusive version of the well-known bouncing ball problem on a flat vibrating plate. Computer simulations show that the diffusion coefficient of this system is a highly irregular function of the vibration frequency exhibiting pronounced maxima whenever there are resonances between the vibration frequency and the average time of flight of a particle. In addition, there exist irregularities on finer scales that are due to higher-order dynamical correlations pointing towards a fractal structure of this curve. We analyze the diffusive dynamics by classifying the attracting sets and by working out a simple random walk approximation for diffusion, which is systematically refined by using a Green-Kubo formula.

  15. Isoguanine octamer: From bowl to ball

    NASA Astrophysics Data System (ADS)

    Gu, Jiande; Wang, Jing; Leszczynski, Jerzy

    2007-09-01

    Isoguanine (2-oxo-6-amino-guanine, isoG) can form the higher-order self-pairing ionophore structures by regulating the concentration of metal ions. The metal ion coordinated isoG-tetrads adopt bowl-like shape with the metal ion located at the bottom of the bowl. The present study of the formation of the H-bonded octamers ((isoG 4-M +) 2; M + = Na +, K +) illustrates that the bowl-shaped isoG 4-M + complexes are able to form the extraordinary ball-shaped octamers (isoG 4-M +) 2 H-bonded through the H(N6) and N7 sites. A moderate energy barrier predicted for the process of separating the ball-shaped octamer into two bowl-shaped tetrads and the unique structural features of the octamer suggests a possibility towards construction of the self-assembled isoG nanostructures.

  16. Relative locality and the soccer ball problem

    SciTech Connect

    Amelino-Camelia, Giovanni; Freidel, Laurent; Smolin, Lee; Kowalski-Glikman, Jerzy

    2011-10-15

    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}. 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}.

  17. Relative locality and the soccer ball problem

    NASA Astrophysics Data System (ADS)

    Amelino-Camelia, Giovanni; Freidel, Laurent; Kowalski-Glikman, Jerzy; Smolin, Lee

    2011-10-01

    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 Emacro much larger than MP. 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 Emacro/N·MP.

  18. Low-Wear Ball-Bearing Separator

    NASA Technical Reports Server (NTRS)

    Hawkinson, Elden L.

    1991-01-01

    Proposed ball-bearing separator for use in cryogenic pump stronger and more resistant to wear. Consists of molded plastic-and-metal composite ring imbued with solid lubricant and containing embedded metal ring. Obtains combination of strength and lubricity. Before molding and machining, ring includes tooling portion for handling and indexing. Molded composite blend of PTFE and fluorinated ethylene/propylene (FEP) filled with brass and bronze powder and molybdenum disulfide powder.

  19. Gravitational effects on critical Q-balls

    NASA Astrophysics Data System (ADS)

    Metaxas, D.

    2007-04-01

    In a cosmological phase transition in theories that admit Q-balls there is a value of the soliton charge above which the soliton becomes unstable and expands, converting space to the true vacuum, much like a critical bubble in the case of ordinary tunneling. Here I consider the effects of gravity on these solitons and I calculate the lowest gravitational corrections to the critical radius and charge.

  20. Free-floating atmospheric pressure ball plasmas

    NASA Astrophysics Data System (ADS)

    Wurden, G. A.; Ticos, C.; Wang, Z.; Wurden, C. J. V.

    2007-11-01

    A long-lived (0.3 second, 10-20 cm diameter) ball plasma floating in the air above a water surface has been formed and studied in the laboratory. A 0.4 - 1 mF capacitor is charged to 4-5 kV, and subsequently discharged (30-60 Amps, 20-50 msec duration) into central copper cathode held fixed just below the surface of a bucket of water (with a weak solution of various salts in distilled water, such as CuSO4 or CuCl2, LiCl or NaCl). An underwater ring anode completes the circuit. A bubble of hot vapor from the water surface rises up in the first few milliseconds, and changes from a mushroom cloud with stalk, to a detached quasi-spherical object, finally evolving into a vortex ring. The plasma consists of ionized water vapor, with positive salts and OH- radicals, as well as molecular species, and it completely excludes nitrogen or oxygen from the rising plasma structure. A fine boundary layer is visible in orange, in contrast to a green ball interior when using Cu/CuSO4, and filamentary structures are visible at late times. Finally, a whisp of smoke ring is observed as a residue. A variety of visible and infrared imaging (both video and still cameras) are used, along with 200-800 nm time & space resolved spectroscopy, to identify features of this laboratory analog to ball lightning. Possible applications include a windowless ball- plasma powered pulsed copper vapor laser operating at 510 nm.

  1. Relation between Hertz Stress-Life Exponent, Ball-Race Conformity, and Ball Bearing Life

    NASA Technical Reports Server (NTRS)

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

    2006-01-01

    ANSI/ABMA and ISO standards based on Lundberg-Palmgren bearing life theory are normalized for ball bearings having inner- and outer-race conformities of 52 percent (0.52) and made from pre-1940 bearing steel. The Lundberg-Palmgren theory incorporates an inverse 9th power relation between Hertz stress and fatigue life for ball bearings. The effect of race conformity on ball set life independent of race life is not incorporated into the Lundberg-Palmgren theory. In addition, post-1960 vacuum-processed bearing steel exhibits a 12th power relation between Hertz stress and life. The work reported extends the previous work of Zaretsky, Poplawski, and Root to calculate changes in bearing life, that includes the life of the ball set, caused by race conformity, Hertz stress-life exponent, ball bearing type and bearing series. The bearing fatigue life in actual application will usually be equal to or greater than that calculated using the ANSI/ABMA and ISO standards that incorporate the Lundberg-Palmgren theory. The relative fatigue life of an individual race is more sensitive to changes in race conformity for Hertz stress-life exponent n of 12 than where n = 9. However, when the effects are combined to predict actual bearing life for a specified set of conditions and bearing geometry, the predicted life of the bearing will be greater for a value of n = 12 than n = 9.

  2. Relation Between Hertz Stress-Life Exponent, Ball-Race Conformity, and Ball Bearing Life

    NASA Technical Reports Server (NTRS)

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

    2008-01-01

    ANSI/ABMA and ISO standards based on Lundberg-Palmgren bearing life theory are normalized for ball bearings having inner- and outerrace conformities of 52 percent (0.52) and made from pre-1940 bearing steel. The Lundberg-Palmgren theory incorporates an inverse 9th power relation between Hertz stress and fatigue life for ball bearings. The effect of race conformity on ball set life independent of race life is not incorporated into the Lundberg-Palmgren theory. In addition, post-1960 vacuum-processed bearing steel exhibits a 12th power relation between Hertz stress and life. The work reported extends the previous work of Zaretsky, Poplawski, and Root to calculate changes in bearing life--that includes the life of the ball set--caused by race conformity, Hertz stress-life exponent, ball bearing type and bearing series. The bearing fatigue life in actual application will usually be equal to or greater than that calculated using the ANSI/ABMA and ISO standards that incorporate the Lundberg-Palmgren theory. The relative fatigue life of an individual race is more sensitive to changes in race conformity for Hertz stress-life exponent n of 12 than where n = 9. However, when the effects are combined to predict actual bearing life for a specified set of conditions and bearing geometry, the predicted life of the bearing will be greater for a value of n = 12 than n = 9.

  3. Detecting targets hidden in random forests

    NASA Astrophysics Data System (ADS)

    Kouritzin, Michael A.; Luo, Dandan; Newton, Fraser; Wu, Biao

    2009-05-01

    Military tanks, cargo or troop carriers, missile carriers or rocket launchers often hide themselves from detection in the forests. This plagues the detection problem of locating these hidden targets. An electro-optic camera mounted on a surveillance aircraft or unmanned aerial vehicle is used to capture the images of the forests with possible hidden targets, e.g., rocket launchers. We consider random forests of longitudinal and latitudinal correlations. Specifically, foliage coverage is encoded with a binary representation (i.e., foliage or no foliage), and is correlated in adjacent regions. We address the detection problem of camouflaged targets hidden in random forests by building memory into the observations. In particular, we propose an efficient algorithm to generate random forests, ground, and camouflage of hidden targets with two dimensional correlations. The observations are a sequence of snapshots consisting of foliage-obscured ground or target. Theoretically, detection is possible because there are subtle differences in the correlations of the ground and camouflage of the rocket launcher. However, these differences are well beyond human perception. To detect the presence of hidden targets automatically, we develop a Markov representation for these sequences and modify the classical filtering equations to allow the Markov chain observation. Particle filters are used to estimate the position of the targets in combination with a novel random weighting technique. Furthermore, we give positive proof-of-concept simulations.

  4. SnapShot: Olfactory Classical Conditioning of Drosophila.

    PubMed

    Davis, Ronald L

    2015-10-01

    This SnapShot summarizes current knowledge about the molecules and circuitry that mediate olfactory memory formation in Drosophila, with emphasis on neural circuits carrying the learned sensory information; the molecular mechanisms for acquisition, memory storage, and forgetting; and the output pathways for memory expression. To view this SnapShot, open or download the PDF. PMID:26451491

  5. SnapShot: SMC Protein Complexes Part I.

    PubMed

    Haering, Christian H; Gruber, Stephan

    2016-01-14

    This first of two SnapShots on SMC proteins depicts the composition and architecture of SMC protein complexes and their regulators. Their roles at different stages of the cell cycle will appear in Part II. To view this SnapShot, open or download the PDF. PMID:26771499

  6. I'm Pregnant. Should I Get a Flu Shot?

    MedlinePlus

    ... Cuts? I'm Pregnant. Should I Get a Flu Shot? KidsHealth > For Teens > I'm Pregnant. Should I Get a Flu Shot? Print A A A Text Size I ... weeks pregnant. Do I need to get the flu vaccine or will it affect my pregnancy? – Eliza* ...

  7. 30 CFR 75.1320 - Multiple-shot blasting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Multiple-shot blasting. 75.1320 Section 75.1320... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1320 Multiple-shot blasting... periods of 1,000 milliseconds or less shall be used. (d) When blasting in anthracite mines, each...

  8. Comparative toxicity of lead shot in black ducks and mallards

    USGS Publications Warehouse

    Rattner, B.A.; Fleming, W.J.

    1988-01-01

    An extreme sensitivity of pen-reared black ducks (BDs) to lead shot was observed incidental to development of an enzyme assay (Pain & Rattner, 1988). Intubation of pen-reared BDs with one no. 4 lead shot resulted in 60% mortality in 6 days. It was concluded that BDs were more sensitive to lead shot than expected, or that lead toxicity may be exacerbated by stressful conditions (elevated temperature, confinement in small pens). We reexamined lead shot toxicity in BDs and mallards (MLs). In winter 1986 (Ta=1.7-14.6? C), pen-reared and wild BDs, and game-farm and wild MLs were sham-dosed or given one no. 4 shot. After 14 days, dosed birds were redosed with two or four additional shot. Since the original observation of enhanced. shot toxicity to BDs occurred during summer, the study was also repeated in summer 1987 (Ta=I7:6-30.9?C), with pen-reared BDs and game-farm MLs. Mortality, overt intoxication, weight change, aminolevulinic acid dehydratase activity, and protoporphyrin concentration were used to compare sensitivity among groups. Sensitivity to lead shot was similar between BDs and MLs. However, the wild ducks appeared more vulnerable than their domesticated counterparts, and signs of intoxication were more pronounced in winter than in summer.

  9. Toxicity of Lead and Proposed Substitute Shot to Mallards

    USGS Publications Warehouse

    Longcore, J.R.; Andrews, R.; Locke, L.N.; Bagley, G.E.; Young, L.T.

    1974-01-01

    Poisoning of North American waterfowl resulting from the ingestion of lead shot by ducks, geese, and swans causes an estimated annual mortality of 2 to 3% of the population (Bellrose 1959). To alleviate this problem the search for a suitable substitute for lead has been underway since the early 1950's. Proposed substitutes for lead shot were evaluated in a series of acute toxicity tests with pen-reared mallards (Anas platyrhynchos). Most candidate materials were as toxic to ducks as commercial lead shot. Coating or alloying lead with other metals only delayed mortality among dosed ducks. The reputedly 'disintegrable' lead shot with the water-soluble binder and the lead containing biochemical additives were also as toxic to mallards as the commercial lead shot. Mortality was not significantly different among lead-dosed adult or first-year hen and drake pen-reared mallards; lead-dosed adult, wild mallards of both sexes; and lead-dosed adult, male black ducks (Anas rubripes). The ingestion of one lead shot, size 4, by each of 80 pen-reared mallards caused an average 19% mortality. The presence and type of grit in the gizzard had a measurable effect on erosion of ingested shot and on shot retention among dosed mallards. Significantly fewer lead-dosed ducks died when fed crushed oystershell grit than when fed either quartz grit or no grit.

  10. 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.

  11. 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.

  12. 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.

  13. Charged Q -balls in gauge mediated SUSY breaking models

    NASA Astrophysics Data System (ADS)

    Hong, Jeong-Pyong; Kawasaki, Masahiro; Yamada, Masaki

    2015-09-01

    It is known that after Affleck-Dine baryogenesis, spatial inhomogeneities of Affleck-Dine field grow into nontopological solitons called Q-balls. In gauge mediated supersymmetry (SUSY) breaking models, sufficiently large Q-balls with baryon charge are stable while Q-balls with lepton charge can always decay into leptons. For a Q-ball that carries nonzero B and L charges, the difference between the baryonic component and the leptonic component in decay rate may induce nonzero electric charge on the Q-ball. This implies that a charged Q-ball, also called gauged Q-ball, may emerge in our universe. In this paper, we investigate two complex scalar fields, a baryonic scalar field and a leptonic one, in an Abelian gauge theory. We find stable solutions of gauged Q-balls for different baryon and lepton charges. Those solutions show that a Coulomb potential arises and the Q-ball becomes electrically charged as expected. It is energetically favored that some amount of leptonic component decays, but there is an upper bound on its amount due to the Coulomb force. The baryonic decay also becomes possible by virtue of electrical repulsion, but we find that the evolution itself stops before it occurs mainly due to the Schwinger limit, so that the charged Q-balls eventually survive in the universe.

  14. Equilibrium and shot noise in mesoscopic systems

    SciTech Connect

    Martin, T.

    1994-10-01

    Within the last decade, there has been a resurgence of interest in the study of noise in Mesoscopic devices, both experimentally and theoretically. Noise in solid state devices can have different origins: there is 1/f noise, which is believed to arise from fluctuations in the resistance of the sample due to the motion of impurities. On top of this contribution is a frequency independent component associated with the stochastic nature of electron transport, which will be the focus of this paper. If the sample considered is small enough that dephasing and inelastic effects can be neglected, equilibrium (thermal) and excess noise can be completely described in terms of the elastic scattering properties of the sample. As mentioned above, noise arises as a consequence of random processes governing the transport of electrons. Here, there are two sources of randomness: first, electrons incident on the sample occupy a given energy state with a probability given by the Fermi-Dirac distribution function. Secondly, electrons can be transmitted across the sample or reflected in the same reservoir where they came from with a probability given by the quantum mechanical transmission/reflection coefficients. Equilibrium noise refers to the case where no bias voltage is applied between the leads connected to the sample, where thermal agitation alone allows the electrons close to the Fermi level to tunnel through the sample. In general, equilibrium noise is related to the conductance of the sample via the Johnson-Nyquist formula. In the presence of a bias, in the classical regime, one expects to recover the full shot noise < {Delta}{sup 2}I >= 2I{Delta}{mu} as was observed a long time ago in vacuum diodes. In the Mesoscopic regime, however, excess noise is reduced below the shot noise level. The author introduces a more intuitive picture, where the current passing through the device is a superposition of pulses, or electron wave packets, which can be transmitted or reflected.

  15. Seasonal ingestion of toxic and nontoxic shot by Canada geese

    USGS Publications Warehouse

    DeStefano, S.; Brand, C.J.; Samuel, M.D.

    1995-01-01

    We used rates of ingested shot and elevated blood-lead levels (≥0.18 ppm) to estimate the proportion of Canada geese (Branta canadensis) exposed to lead on 3 study areas in Manitoba, Minnesota, and Missouri. Lead exposure was prevalent on all areas and was common after the hunting season closed, when up to 15% of geese could have been exposed to lead shot. However, the proportion of steel shot ingested by geese has increased during the past 2 decades. We suggest that lead exposure is still a source of indirect hunting mortality in Canada geese but project that the prevalence of lead exposure in the Eastern Prairie Population and other waterfowl populations will decrease as nontoxic shot regulations persist and hunters use steel or other nontoxic shot.

  16. Hyperchaotic qualities of the ball motion in a ball milling device

    NASA Astrophysics Data System (ADS)

    Caravati, C.; Delogu, F.; Cocco, G.; Rustici, M.

    1999-03-01

    Ball collisions in milling devices are governed by complex dynamics ruled by impredictable impulsive forces. In this paper, nonlinear dynamics techniques are employed to analyze the time series describing the trajectory of a milling ball in an empty container obtained from a numerical model. The attractor underlying the system dynamics was reconstructed by the time delay method. In order to characterize the system dynamics the calculation of the spectrum of Lyapunov exponents was performed. Six Lyapunov exponents, divided into two terns with opposite sign, were obtained. The detection of the positive tern demonstrates the occurrence of the hyperchaotic qualities of the ball motion. A fractal Lyapunov dimension, equal to 5.62, was also obtained confirming the strange features of the attractor.

  17. Hyperchaotic qualities of the ball motion in a ball milling device.

    PubMed

    Caravati, C.; Delogu, F.; Cocco, G.; Rustici, M.

    1999-03-01

    Ball collisions in milling devices are governed by complex dynamics ruled by impredictable impulsive forces. In this paper, nonlinear dynamics techniques are employed to analyze the time series describing the trajectory of a milling ball in an empty container obtained from a numerical model. The attractor underlying the system dynamics was reconstructed by the time delay method. In order to characterize the system dynamics the calculation of the spectrum of Lyapunov exponents was performed. Six Lyapunov exponents, divided into two terns with opposite sign, were obtained. The detection of the positive tern demonstrates the occurrence of the hyperchaotic qualities of the ball motion. A fractal Lyapunov dimension, equal to 5.62, was also obtained confirming the strange features of the attractor. (c) 1999 American Institute of Physics. PMID:12779817

  18. Hidden treasures - 50 km points of interests

    NASA Astrophysics Data System (ADS)

    Lommi, Matias; Kortelainen, Jaana

    2015-04-01

    Tampere is third largest city in Finland and a regional centre. During 70's there occurred several communal mergers. Nowadays this local area has both strong and diversed identity - from wilderness and agricultural fields to high density city living. Outside the city center there are interesting geological points unknown for modern city settlers. There is even a local proverb, "Go abroad to Teisko!". That is the area the Hidden Treasures -student project is focused on. Our school Tammerkoski Upper Secondary School (or Gymnasium) has emphasis on visual arts. We are going to offer our art students scientific and artistic experiences and knowledge about the hidden treasures of Teisko area and involve the Teisko inhabitants into this project. Hidden treasures - Precambrian subduction zone and a volcanism belt with dense bed of gold (Au) and arsenic (As), operating goldmines and quarries of minerals and metamorphic slates. - North of subduction zone a homogenic precambrian magmastone area with quarries, products known as Kuru Grey. - Former ashores of post-glasial Lake Näsijärvi and it's sediments enabled the developing agriculture and sustained settlement. Nowadays these ashores have both scenery and biodiversity values. - Old cattle sheds and dairy buildings made of local granite stones related to cultural stonebuilding inheritance. - Local active community of Kapee, about 100 inhabitants. Students will discover information of these "hidden" phenomena, and rendering this information trough Enviromental Art Method. Final form of this project will be published in several artistic and informative geocaches. These caches are achieved by a GPS-based special Hidden Treasures Cycling Route and by a website guiding people to find these hidden points of interests.

  19. Orchestrating Shots for the National Ignition Facililty (NIF)

    SciTech Connect

    Mathisen, D G; Bettenhausen, R C; Beeler, R G; Bowers, G A; Carey, R W; Casavant, D D; Cline, B D; Demaret, R D; Domyancic, D M; Elko, S D; Fisher, J M; Krammen, J E; Lagin, L J; Ludwigsen, A P; Patterson, R W; Sanchez, R J; Stout, E A

    2005-05-12

    The National Ignition Facility (NIF), currently under construction at the Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8 Megajoule, 500-Terawatt, ultra-violet laser system together with a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. When completed, NIF will be the world's largest and most energetic laser experimental system, providing an international center to study inertial confinement fusion and physics of matter at extreme densities and pressures. The NIF is operated by the Integrated Computer Control System (ICCS), which is a layered architecture of over 700 lower-level front-end processors attached to nearly 60,000 control points and coordinated by higher-level supervisory subsystems in the main control room. A shot automation framework has been developed and deployed during the past year to orchestrate and automate shots performed at the NIF using the ICCS. The Shot Automation framework is designed to automate 4-8 hour shot sequences, that includes deriving shot goals from an experiment definition, set up of the laser and diagnostics, automatic alignment of laser beams, and a countdown to charge and fire the lasers. These sequences consist of set of preparatory verification shots, leading to amplified system shots followed by post-shot analysis and archiving. The framework provides for a flexible, model-based work-flow execution, driven by scripted automation called macro steps. The shot director software is the orchestrating component of a very flexible automation layer which allows us to define, coordinate and reuse simpler automation sequences. This software provides a restricted set of shot life cycle state transitions to 26 collaboration supervisors that automate 8-laser beams (bundle) and a common set of shared resources. Each collaboration supervisor commands approximately 10 subsystem shot supervisors that perform automated control and status verification

  20. Friedel oscillations: Decoding the hidden physics

    NASA Astrophysics Data System (ADS)

    Bena, Cristina

    2016-03-01

    We show that the impurity-induced Friedel oscillations allow one to probe in an unexpected and quite remarkable manner the electronic properties of two-dimensional systems such as graphene or high-temperature superconductors. In particular, we show that by studying these oscillations, one can get access not only to the constant-energy maps, but also to more hidden information such as the chiral properties of Dirac electrons in graphene, which cannot be observed directly by other methods. For graphene, this hidden information is revealed by comparing the theoretical predictions with scanning tunneling microscopy experimental measurements of the local density of states. xml:lang="fr"

  1. Signatures of a hidden cosmic microwave background.

    PubMed

    Jaeckel, Joerg; Redondo, Javier; Ringwald, Andreas

    2008-09-26

    If there is a light Abelian gauge boson gamma' in the hidden sector its kinetic mixing with the photon can produce a hidden cosmic microwave background (HCMB). For meV masses, resonant oscillations gamma<-->gamma' happen after big bang nucleosynthesis (BBN) but before CMB decoupling, increasing the effective number of neutrinos Nnu(eff) and the baryon to photon ratio, and distorting the CMB blackbody spectrum. The agreement between BBN and CMB data provides new constraints. However, including Lyman-alpha data, Nnu(eff) > 3 is preferred. It is tempting to attribute this effect to the HCMB. The interesting parameter range will be tested in upcoming laboratory experiments. PMID:18851438

  2. Mucormycosis (Mucor fungus ball) of the maxillary sinus.

    PubMed

    Cho, Hang Sun; Yang, Hoon Shik; Kim, Kyung Soo

    2014-01-01

    A fungus ball is an extramucosal fungal proliferation that completely fills one or more paranasal sinuses and usually occurs as a unilateral infection. It is mainly caused by Aspergillus spp in an immunocompetent host, but some cases of paranasal fungal balls reportedly have been caused by Mucor spp. A Mucor fungus ball is usually found in the maxillary sinus and/or the sphenoid sinus and may be black in color. Patients with mucormycosis, or a Mucor fungal ball infection, usually present with facial pain or headache. On computed tomography, there are no pathognomonic findings that are conclusive for a diagnosis of mucormycosis. In this article we report a case of mucormycosis in a 56-year-old woman and provide a comprehensive review of the literature on the "Mucor fungus ball." To the best of our knowledge, 5 case reports (8 patients) have been published in which the fungus ball was thought to be caused by Mucor spp. PMID:25397383

  3. New model and estimation of the danger of ball lightning

    NASA Astrophysics Data System (ADS)

    Shmatov, M. L.

    2003-12-01

    A new model of ball lightning is proposed. The main model assumption is that ball lightning has a core consisting of clouds of electrons and totally ionized ions which oscillate with respect to each other. According to the model, ball lightning emits high energy photons that are sometimes dangerous for human beings, and in a number of situations it can kill humans by electric pulses; the ball lightning energy can be of the order of 106 J and even greater. The electric charges that need to be injected into the atmosphere to create ball lightning and the currents, providing the injection of such charges, are estimated. These estimates predict that ball lightning can be created in the experiments with ordinary lightning or powerful electrical installations.

  4. 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.

  5. Magnetohydrodynamics equilibrium of a self-confined elliptical plasma ball

    SciTech Connect

    Wu, H. P. O. Box 8730, Beijing 100080 and Institute of Mechanics, Academia Sinica, Beijing, People's Republic of China ); Oakes, M.E. )

    1991-08-01

    A variational principle is applied to the problem of magnetohydrodynamics (MHD) equilibrium of a self-contained elliptical plasma ball, such as elliptical ball lightning. The principle is appropriate for an approximate solution of partial differential equations with arbitrary boundary shape. The method reduces the partial differential equation to a series of ordinary differential equations and is especially valuable for treating boundaries with nonlinear deformations. The calculations conclude that the pressure distribution and the poloidal current are more uniform in an oblate self-confined plasma ball than that of an elongated plasma ball. The ellipticity of the plasma ball is obviously restricted by its internal pressure, magnetic field, and ambient pressure. Qualitative evidence is presented for the absence of sighting of elongated ball lightning.

  6. Burning molten metallic spheres: One class of ball lightning?

    NASA Astrophysics Data System (ADS)

    Stephan, Karl D.; Massey, Nathan

    2008-08-01

    Abrahamson and Dinniss [2000. Ball lightning caused by oxidation of nanoparticle networks from normal lightning strikes on soil. Nature 403, 519-521] proposed a theory of ball lighting in which silicon nanoparticles undergo slow oxidation and emit light. Paiva et al. [2007. Production of ball-lightning-like luminous balls by electrical discharges in silicon. Physical Review Letters 98, 048501] reported that an electric arc to silicon produced long-lasting luminous white spheres showing many characteristics of ball lightning. We show experimentally that these consist of burning molten silicon spheres with diameters in the 0.1-1 mm range. The evidence of our experiments leads us to propose that a subset of ball lightning events may consist of macro-scale molten spheres of burning metallic materials likely to be ejected from a conventional lightning strike to earth.

  7. Relationships among balance, visual search, and lacrosse-shot accuracy.

    PubMed

    Marsh, Darrin W; Richard, Leon A; Verre, Arlene B; Myers, Jay

    2010-06-01

    The purpose of this study was to examine variables that may contribute to shot accuracy in women's college lacrosse. A convenience sample of 15 healthy women's National Collegiate Athletic Association Division III College lacrosse players aged 18-23 (mean+/-SD, 20.27+/-1.67) participated in the study. Four experimental variables were examined: balance, visual search, hand grip strength, and shoulder joint position sense. Balance was measured by the Biodex Stability System (BSS), and visual search was measured by the Trail-Making Test Part A (TMTA) and Trail-Making Test Part B (TMTB). Hand-grip strength was measured by a standard hand dynamometer, and shoulder joint position sense was measured using a modified inclinometer. All measures were taken in an indoor setting. These experimental variables were then compared with lacrosse-shot error that was measured indoors using a high-speed video camera recorder and a specialized L-shaped apparatus. A Stalker radar gun measured lacrosse-shot velocity. The mean lacrosse-shot error was 15.17 cm with a mean lacrosse-shot velocity of 17.14 m.s (38.35 mph). Lower scores on the BSS level 8 eyes open (BSS L8 E/O) test and TMTB were positively related to less lacrosse-shot error (r=0.760, p=0.011) and (r=0.519, p=0.048), respectively. Relations were not significant between lacrosse-shot error and grip strength (r=0.191, p = 0.496), lacrosse-shot error and BSS level 8 eyes closed (BSS L8 E/C) (r=0.501, p=0.102), lacrosse-shot error and BSS level 4 eyes open (BSS L4 E/O) (r=0.313, p=0.378), lacrosse-shot error and BSS level 4 eyes closed (BSS L4 E/C) (r=-0.029, p=0.936) lacrosse-shot error and shoulder joint position sense (r=-0.509, p=0.055) and between lacrosse-shot error and TMTA (r=0.375, p=0.168). The results reveal that greater levels of shot accuracy may be related to greater levels of visual search and balance ability in women college lacrosse athletes. PMID:20508452

  8. 'Hidden' Brain Injury a Challenge for Military Doctors

    MedlinePlus

    ... nih.gov/medlineplus/news/fullstory_159316.html 'Hidden' Brain Injury a Challenge for Military Doctors Potentially fatal ... may suffer from a distinctive pattern of "hidden" brain injury, a small study finds. "Blast-related brain ...

  9. Impact of a ball on a surface with tangential compliance

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2010-07-01

    A simple model is presented to explain how the spin of a ball can be enhanced when the ball is incident obliquely on a flexible surface. The mechanism involves tangential distortion of the surface and a return of the elastic energy stored in the surface via the action of the static friction force on the ball. As an example, we consider the enhancement of the spin that is possible using an appropriate type of tennis racquet string.

  10. Ground states of baryoleptonic Q-balls in supersymmetric models

    SciTech Connect

    Shoemaker, Ian M.; Kusenko, Alexander

    2008-10-01

    In supersymmetric generalizations of the standard model, all stable Q-balls are associated with some flat directions. We show that, if the flat direction has both the baryon number and the lepton number, the scalar field inside the Q-ball can deviate slightly from the flat direction in the ground state. We identify the true ground states of such nontopological solitons, including the electrically neutral and electrically charged Q-balls.

  11. Experiments on Structure and Trapping of Coulomb balls

    SciTech Connect

    Block, D.; Arp, O.; Piel, A.; Melzer, A.

    2006-10-18

    This paper gives a survey of recent experiments on Coulomb balls. Starting with typical observations to introduce the Coulomb ball experiment and its diagnostic potential, their structural properties are discussed. Further, the trapping mechanism for the dust is quantified to allow for a systematic comparison of experiment and simulations. Finally, the presented results focus on the question how screening influences the structural properties and how Coulomb balls and other strongly coupled systems are related.

  12. DETAIL VIEW OF BALL MILL FEED SYSTEM, MOUTH OF CLASSIFIER, ...

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

    DETAIL VIEW OF BALL MILL FEED SYSTEM, MOUTH OF CLASSIFIER, AND ORE BIN CHUTE, LOOKING EAST NORTHEAST. CRUSHED ORE FROM THE SECONDARY ORE BIN WAS INTRODUCED INTO THE FEED TROUGH VIA A CHUTE. AS THE BALL MILL TURNED, THE ROUND SCOOP ALSO TURNED IN THE TROUGH TO CHANNEL ORE INTO THE BALL MILL. SEE CA-292-14 FOR IDENTICAL B&W NEGATIVE. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  13. DETAIL VIEW OF BALL MILL FEED SYSTEM, MOUTH OF CLASSIFIER, ...

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

    DETAIL VIEW OF BALL MILL FEED SYSTEM, MOUTH OF CLASSIFIER, AND ORE BIN CHUTE, LOOKING EAST NORTHEAST. CRUSHED ORE FROM THE SECONDARY ORE BIN WAS INTRODUCED INTO THE FEED TROUGH VIA A CHUTE. AS THE BALL MILL TURNED, THE ROUND SCOOP ALSO TURNED IN THE TROUGH TO CHANNEL ORE INTO THE BALL MILL. SEE CA-292-20 (CT) FOR IDENTICAL COLOR TRANSPARENCY. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  14. Single-shot fluctuations in waveguided high-harmonic generation.

    PubMed

    Goh, S J; Tao, Y; van der Slot, P J M; Bastiaens, H J M; Herek, J; Biedron, S G; Danailov, M B; Milton, S V; Boller, K-J

    2015-09-21

    For exploring the application potential of coherent soft x-ray (SXR) and extreme ultraviolet radiation (XUV) provided by high-harmonic generation, it is important to characterize the central output parameters. Of specific importance are pulse-to-pulse (shot-to-shot) fluctuations of the high-harmonic output energy, fluctuations of the direction of the emission (pointing instabilities), and fluctuations of the beam divergence and shape that reduce the spatial coherence. We present the first single-shot measurements of waveguided high-harmonic generation in a waveguided (capillary-based) geometry. Using a capillary waveguide filled with Argon gas as the nonlinear medium, we provide the first characterization of shot-to-shot fluctuations of the pulse energy, of the divergence and of the beam pointing. We record the strength of these fluctuations vs. two basic input parameters, which are the drive laser pulse energy and the gas pressure in the capillary waveguide. In correlation measurements between single-shot drive laser beam profiles and single-shot high-harmonic beam profiles we prove the absence of drive laser beam-pointing-induced fluctuations in the high-harmonic output. We attribute the main source of high-harmonic fluctuations to ionization-induced nonlinear mode mixing during propagation of the drive laser pulse inside the capillary waveguide. PMID:26406689

  15. Concrete Cleaning, Inc. centrifugal shot blaster: Baseline report

    SciTech Connect

    1997-07-31

    The centrifugal shot blaster technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The centrifugal shot blaster is an electronically operated shot blast machine that has been modified to remove layers of concrete to varying depths. A hardened steel shot propelled at a high rate of speed abrades the surface of the concrete. The depth of material removed is determined by the rate of speed the machine is traveling and the volume of shot being fired into the blast chamber. The steel shot is recycled and used over until it is pulverized into dust, which ends up in the waste container with the concrete being removed. Debris is continually vacuumed by a large dust collection system attached to the shot blaster. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

  16. Concrete Cleaning, Inc. centrifugal shot blaster: Baseline report; Greenbook (chapter)

    SciTech Connect

    1997-07-31

    The centrifugal shot blaster technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The centrifugal shot blaster is an electronically operated shot blast machine that has been modified to remove layers of concrete to varying depths. A hardened steel shot propelled at a high rate of speed abrades the surface of the concrete. The depth of material removed is determined by the rate of speed the machine is traveling and the volume of shot being fired into the blast chamber. The steel shot is recycled and used over until it is pulverized into dust, which ends up in the waste container with the concrete being removed. Debris is continually vacuumed by a large dust collection system attached to the shot blaster. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

  17. Spherical microwave confinement and ball lightning

    NASA Astrophysics Data System (ADS)

    Robinson, William Richard

    This dissertation presents the results of research done on unconventional energy technologies from 1995 to 2009. The present civilization depends on an infrastructure that was constructed and is maintained almost entirely using concentrated fuels and ores, both of which will run out. Diffuse renewable energy sources rely on this same infrastructure, and hence face the same limitations. I first examined sonoluminescence directed toward fusion, but demonstrated theoretically that this is impossible. I next studied Low Energy Nuclear Reactions and developed methods for improving results, although these have not been implemented. In 2000, I began Spherical Microwave Confinement (SMC), which confines and heats plasma with microwaves in a spherical chamber. The reactor was designed and built to provide the data needed to investigate the possibility of achieving fusion conditions with microwave confinement. A second objective was to attempt to create ball lightning (BL). The reactor featured 20 magnetrons, which were driven by a capacitor bank and operated in a 0.2 s pulse mode at 2.45 GHz. These provided 20 kW to an icosahedral array of 20 antennas. Video of plasmas led to a redesign of the antennas to provide better coupling of the microwaves to the plasma. A second improvement was a grid at the base of the antennas, which provided corona electrons and an electric field to aid quick formation of plasmas. Although fusion conditions were never achieved and ball lightning not observed, experience gained from operating this basic, affordable system has been incorporated in a more sophisticated reactor design intended for future research. This would use magnets that were originally planned. The cusp geometry of the magnetic fields is suitable for electron cyclotron resonance in the same type of closed surface that in existing reactors has generated high-temperature plasmas. Should ball lightning be created, it could be a practical power source with nearly ideal

  18. 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.

  19. Charmonium studies with the crystal ball

    SciTech Connect

    Oreglia, M.

    1980-06-01

    The Crystal Ball detector at SPEAR is used to analyze the decays psi' ..-->.. ..gamma gamma..psi and psi' ..-->.. ..gamma..chi,chi ..-->.. ..gamma gamma... Values are obtained for the branching ratios of psi' ..-->.. eta/..mu../sup 0/psi and psi' ..-->.. ..gamma..chi,chi ..-->.. ..gamma..psi. No evidence is found for a 2/sup 1/S/sub 0/(eta'c) state in the mass range 3129 ..-->.. 3644 MeV/c/sup 2/. Analysis of the angular distributions in the cascade chi decays yields spin and multipole assignments for the chi(3.51) and chi(3.55).

  20. Robin conditions on the Euclidean ball

    NASA Astrophysics Data System (ADS)

    Dowker, J. S.

    1996-04-01

    Techniques are presented for calculating directly the scalar functional determinant on the Euclidean d-ball. General formulae are given for Dirichlet and Robin boundary conditions when d is even and the field is massless. The method involves a large mass asymptotic limit which is carried out in detail for d = 2 as an exercise, incidentally producing some specific summations and identities. Extensive use is made of the Watson - Kober summation formula. The calculation of the finite-mass determinant is also briefly considered.

  1. Crystal Ball evidence for new states

    SciTech Connect

    Coyne, D.G.

    1981-09-01

    Evidence for three new particles observed in the Crystal Ball detector is presented. The first particle, at 3592 MeV, is seen inclusively in ..gamma.. transitions from psi', and is thus a candidate for eta/sub c/'. The other two, at 1440 and 1640 MeV, are best seen in exclusive decays of psi involving a prompt ..gamma.., and are thus candidates for bound states of two gluons. Detailed reasons are presented to support the contention that these states are distinct from previously observed candidates such as E(1420). Alternative hypotheses are discussed.

  2. Possible astronomical meaning of the Povlen ball

    NASA Astrophysics Data System (ADS)

    Ducić, V.; Petrović, R.

    2003-10-01

    The Povlen ball is a spherical rock in the Povlen mountain, near Valjevo, on which the indented signs are found. Archeological team of Petnica Research Center suggested the possible meaning of these signs. They claimed that these marks are signs of "Sepherd insciptions". We noticed two groups of signs: ones like dimples and the others like figures. Working hypothesis is that five gathered dimples could represent constellation of Cepheus, partially fulfill our expectations. Besides, there is the possibility that one figure represents constellation of Cygnus (Cross). Both of these constellations are used for orientation on the sky, and similar archeoastronomical objects were funded in Bulgaria.

  3. When Two Balls Are Just One

    NASA Astrophysics Data System (ADS)

    Kulp, Christopher W.; Biermann, Mark L.; Howard, Timothy; Klingenberg, Kurtis; Ramsey, Paul

    2008-03-01

    A camcorder can be a powerful tool in pedagogical settings, such as in an introductory physics course or in introducing undergraduates to data collection. In this paper, we discuss our experience using a Panasonic PV-GS150 digital camcorder to analyze the motion of a falling steel ball, with the goal of determining the acceleration due to gravity, g = 9.80 m/s2. When performing this simple experiment, an interesting technical issue arose that led to an excellent teaching opportunity that is based on an unexpected and intriguing method of computing g.

  4. Ball Bearing Analysis with the ORBIS Tool

    NASA Technical Reports Server (NTRS)

    Halpin, Jacob D.

    2016-01-01

    Ball bearing design is critical to the success of aerospace mechanisms. Key bearing performance parameters, such as load capability, stiffness, torque, and life all depend on accurate determination of the internal load distribution. Hence, a good analytical bearing tool that provides both comprehensive capabilities and reliable results becomes a significant asset to the engineer. This paper introduces the ORBIS bearing tool. A discussion of key modeling assumptions and a technical overview is provided. Numerous validation studies and case studies using the ORBIS tool are presented. All results suggest the ORBIS code closely correlates to predictions on bearing internal load distributions, stiffness, deflection and stresses.

  5. Are Perytons Signatures of Ball Lightning?

    NASA Astrophysics Data System (ADS)

    Dodin, I. Y.; Fisch, N. J.

    2014-10-01

    The enigmatic downchirped signals, called "perytons," that are detected by radio telescopes in the GHz frequency range may be produced by an atmospheric phenomenon known as ball lightning (BL). If BLs act as nonstationary radio frequency cavities, their characteristic emission frequencies and evolution timescales are consistent with peryton observations, and so are general patterns in which BLs are known to occur. Based on this evidence, testable predictions are made that can confirm or rule out a causal connection between perytons and BLs. In either case, how perytons are searched for in observational data may warrant reconsideration because existing procedures may be discarding events that have the same nature as known perytons.

  6. Are perytons signatures of ball lightning?

    SciTech Connect

    Dodin, I. Y.; Fisch, N. J.

    2014-10-20

    The enigmatic downchirped signals, called 'perytons', that are detected by radio telescopes in the GHz frequency range may be produced by an atmospheric phenomenon known as ball lightning (BL). If BLs act as nonstationary radio frequency cavities, their characteristic emission frequencies and evolution timescales are consistent with peryton observations, and so are general patterns in which BLs are known to occur. Based on this evidence, testable predictions are made that can confirm or rule out a causal connection between perytons and BLs. In either case, how perytons are searched for in observational data may warrant reconsideration because existing procedures may be discarding events that have the same nature as known perytons.

  7. Multiprocessor data acquisition for NordBall

    NASA Astrophysics Data System (ADS)

    Jerrestam, Dan; Forycki, A.; Holm, A.; Høy-Christensen, P.; Jian Shen, T.

    1989-12-01

    For the NordBall multidetector system a versatile data acquisition system has been developed around the VME bus utilizing 68010 processors. The readout of the instrument is based on a generalized READER concept. READERs are CPU boards reading hardware in parallel for each event. In the FERA bus the final fast logical decision is made before an event is to be considered as being present for readout. Synchronization with the trigger for readout, coming from the FERA bus system, is performed by a special hardware unit. Synchronization on event level between the READERs is done by the same hardware unit monitored by a master CPU.

  8. Predicting where a ball will land: from thrower's body language to ball's motion.

    PubMed

    Prigent, Elise; Hansen, Clint; Baurès, Robin; Darracq, Cécile; Amorim, Michel-Ange

    2015-02-01

    To predict where a thrown ball will land, an observer may use visual information about its trajectory. However, in addition, the thrower's body language (i.e., body movement and facial expression) may contain useful information that could be used by the observer to understand intention and emotional state. Here, we investigated how observers estimated a ball's landing point thrown by a virtual agent with different amounts of information from body language. In addition, occlusion time was varied to examine how it potentiates the use of body-language information. Results showed that body movement and facial expression carry information about thrower's effort. However, once the ball has left the thrower's hand, advance information on facial expression does contribute to judgments only if consistent with the amplitude of the throw. Moreover, as the occlusion time increases, a stronger influence of the body movement is observed for estimating the landing point. The overriding effect of ball's trajectory availability over body language is discussed. PMID:25362519

  9. Subtleties of Hidden Quantifiers in Implication

    ERIC Educational Resources Information Center

    Shipman, Barbara A.

    2016-01-01

    Mathematical conjectures and theorems are most often of the form P(x) ? Q(x), meaning ?x,P(x) ? Q(x). The hidden quantifier ?x is crucial in understanding the implication as a statement with a truth value. Here P(x) and Q(x) alone are only predicates, without truth values, since they contain unquantified variables. But standard textbook…

  10. The Hidden Labour Market of the Academic.

    ERIC Educational Resources Information Center

    Rouhelo, Anne

    Finding employment as an academic is becoming increasingly challenging for several reasons, including the tightening employment market and increases in the qualifications demanded of jobseekers and the pool of academically trained job seekers. A two-round Delphi study was therefore conducted to identify recruitment channels in the hidden labor…

  11. Dermatologic hazards from hidden contacts with penicillin.

    PubMed

    Boonk, W J

    1981-01-01

    The unbridled use of penicillin after its discovery by Fleming has resulted in possible hazards to human health due to traces of the drug being present in food and other hidden sources. These hazards may include toxic effects, hypersensitivity reactions and possibly a raising of the frequency and duration of allergy to penicillin. PMID:7028441

  12. Hidden Messages: Instructional Materials for Investigating Culture.

    ERIC Educational Resources Information Center

    Finkelstein, Barbara, Ed.; Eder, Elizabeth K., Ed.

    This book, intended to be used in the middle and high school classroom, provides teachers with unique ideas and lesson plans for exploring culture and adding a multicultural perspective to diverse subjects. "Hidden messages" are the messages of culture that are entwined in everyday lives, but which are seldom recognized or appreciated for the…

  13. Registration of 'Hidden Valley' meadow fescue

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Hidden Valley' (Reg. No. CV-xxxx, PI xxxxxx) meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.; syn. Festuca pratensis Huds.; syn. Lolium pratense (Huds.) Darbysh.] is a synthetic population originating from 561 parental genotypes. The original germplasm is of unknown central or northern Europ...

  14. The Hidden Curriculum of Doctoral Advising

    ERIC Educational Resources Information Center

    Harding-DeKam, Jenni L.; Hamilton, Boni; Loyd, Stacy

    2012-01-01

    We examined the hidden curriculum of doctoral advising by conceptualizing the advisor as a teacher. Using autoethnographic methods in this case study, we simultaneously explored both sides of the advisor-student relationship. The constructivist paradigm permeated all aspects of the research: data collection, analysis, and interpretation. The…

  15. Discovering Hidden Treasures with GPS Technology

    ERIC Educational Resources Information Center

    Nagel, Paul; Palmer, Roger

    2014-01-01

    "I found it!" Addison proudly proclaimed, as she used an iPhone and Global Positioning System (GPS) software to find the hidden geocache along the riverbank. Others in Lisa Bostick's fourth grade class were jealous, but there would be other geocaches to find. With the excitement of movies like "Pirates of the Caribbean"…

  16. Hidden Disability and an Academic Career

    ERIC Educational Resources Information Center

    Beretz, Elaine M.

    2003-01-01

    Is fighting a serious illness or recovering from a major injury mutually exclusive with being a professor? Trends in academic employment and societal attitudes toward disability answer that question with a resounding yes. This disturbing state of affairs will continue until people develop ways to accommodate the "hidden" disability of serious…

  17. A Hidden Minority Amidst White Privilege

    ERIC Educational Resources Information Center

    Singer, Miriam J.

    2008-01-01

    It seems rather amusing to say that the author belongs to a minority, no less a hidden minority. After all, at first glance, she appears to be just another white girl (or woman). She grew up in the mid-west in a predominantly white community, middle class, and well educated. The paradox comes in their definition of minority. Today, as they seek to…

  18. Gamma rays from hidden millisecond pulsars

    NASA Technical Reports Server (NTRS)

    Tavani, Marco

    1992-01-01

    The properties were studied of a new class of gamma ray sources consisting of millisecond pulsars totally or partially surrounded by evaporating material from irradiated companion stars. Hidden millisecond pulsars offer a unique possibility to study gamma ray, optical and radio emission from vaporizing binaries. The relevance of this class of binaries for GRO observations and interpretation of COS-B data is emphasized.

  19. Method and device for measuring single-shot transient signals

    DOEpatents

    Yin, Yan

    2004-05-18

    Methods, apparatus, and systems, including computer program products, implementing and using techniques for measuring multi-channel single-shot transient signals. A signal acquisition unit receives one or more single-shot pulses from a multi-channel source. An optical-fiber recirculating loop reproduces the one or more received single-shot optical pulses to form a first multi-channel pulse train for circulation in the recirculating loop, and a second multi-channel pulse train for display on a display device. The optical-fiber recirculating loop also optically amplifies the first circulating pulse train to compensate for signal losses and performs optical multi-channel noise filtration.

  20. Shot H3837: Darht's first dual-axis explosive experiment

    NASA Astrophysics Data System (ADS)

    Harsh, James F.; Hull, Lawrence; Mendez, Jacob; McNeil, Wendy Vogan

    2012-03-01

    Test H3837 was the first explosive shot performed in front of both flash x-ray axes at the Los Alamos Dual Axis Radiographic Hydrodynamic Test (DARHT) facility. Executed in November 2009, the shot was an explosively-driven metal flyer plate in a series of experiments designed to explore equation-of-state properties of shocked materials. Imaging the initial shock wave traveling through the flyer plate, DARHT Axis II captured the range of motion from the shock front emergence in the flyer to breakout at the free surface; the Axis I pulse provided a perpendicular perspective of the shot at a time coinciding with the third pulse of Axis II.

  1. Incidence of ingested lead shot in sora rails

    USGS Publications Warehouse

    Artmann, J.W.; Martin, E.M.

    1975-01-01

    Gizzards of 934 sora rails (Porzana carolina) collected in Maryland (767) and Missouri (167) were examined for ingested shot. Ingested shot were found in 12.3 percent of the Maryland sample and 1.8 percent of the Missouri birds. Individual Maryland birds had ingested up to 28 pellets. None of the lead pellets examined was larger than a No. 7 1/2 shot. Maryland ingestion rates did not differ by age or sex, but significant differences between collection areas, groups of years, and collection periods within years were indicated. This exploratory work points out a potential lead poisoning problem among sora rails.

  2. Lead shot poisoning of a Pacific loon in Alaska

    USGS Publications Warehouse

    Wilson, H.M.; Oyen, J.L.; Sileo, L.

    2004-01-01

    Lead poisoning, associated with ingestion of spent lead shot, was diagnosed in an adult female Pacific loon (Gavia pacifica) observed with partial paralysis on 13 June 2002 and found dead on 16 June 2002 on Kigigak Island, Yukon Delta National Wildlife Refuge, western Alaska, USA. A necropsy revealed three pellets of ingested lead shot in the loona??s gizzard and a lead liver concentration of 31 ppm wet weight, which was consistent with metallic lead poisoning. This is the first report of lead poisoning in a Pacific loon and is the only account of lead toxicosis associated with ingestion of lead shot in any loon species breeding in Alaska.

  3. Corrosion behaviour of commercially pure titanium shot blasted with different materials and sizes of shot particles for dental implant applications.

    PubMed

    Aparicio, Conrado; Gil, F Javier; Fonseca, Carlos; Barbosa, Mario; Planell, Josep Anton

    2003-01-01

    It is well known that the osseointegration of the commercially pure titanium (c.p. Ti) dental implant is improved when the metal is shot blasted in order to increase its surface roughness. This roughness is colonised by bone, which improves implant fixation. However, shot blasting also changes the chemical composition of the implant surface because some shot particles remain adhered on the metal. The c.p. Ti surfaces shot blasted with different materials and sizes of shot particles were tested in order to determine their topographical features (surface roughness, real surface area and the percentage of surface covered by the adhered shot particles) and electrochemical behaviour (open circuit potential, electrochemical impedance spectroscopy and cyclic polarisation). The results demonstrate that the increased surface area of the material because of the increasing surface roughness is not the only cause for differences found in the electrochemical behaviour and corrosion resistance of the blasted c.p. Ti. Among other possible causes, those differences may be attributed to the compressive residual surface stresses induced by shot blasting. All the materials tested have an adequate corrosion and electrochemical behaviour in terms of its possible use as dental implant material. PMID:12419627

  4. First NIF ARC target shot results

    NASA Astrophysics Data System (ADS)

    Chen, Hui; di Nicola, P.; Hermann, M.; Kalantar, D.; Martinez, D.; Tommasini, R.; NIF ARC Team

    2015-11-01

    The commissioning of the Advanced Radiographic Capability (ARC) laser system in the National Ignition Facility (NIF) is currently in progress. ARC laser is designed to ultimately provide eight beamlets with pulse duration adjustable from 1 to 50 ps, and energies up to 1.7 kJ per beamlet. ARC will add critical capability for the NIF facility for creating precision x-ray backlighters needed for many current NIF ICF and HED experiments. ARC can also produce MeV electrons and protons for new science experiment on NIF. In the initial set of experiments, 4 of the 8 beamlets are being commissioned up to 1 kJ per beam at 30 ps pulse length using foil and wire targets. X-ray energy distribution, spot size and pulse duration are measured using various diagnostics. This talk will describe the shot setup and results. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  5. 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

  6. James Moores Ball: Ophthalmologist, medical historian, bibliophile.

    PubMed

    Feibel, Robert M

    2016-08-01

    James Moores Ball (1862-1929) was an ophthalmologist in St. Louis, Missouri, who excelled as a medical historian and collector of rare and historic books about the history of anatomy. During his lifetime, he was best known as the author of a comprehensive, authoritative, and popular textbook titled Modern Ophthalmology First published in 1904, there were five further editions. Ball was very interested in the history of anatomy and wrote two books on this subject, the first being a biography of Andreas Vesalius, one of the earliest in English, and the second a history of the resurrection men or grave robbers who sold corpses to professors of anatomy and surgery for teaching purposes. His legacy today is the 470 volumes of his personal library, which are now in the Archives and Rare Books department of the Becker Medical Library of the Washington University School of Medicine. These texts are one of their major collections, concentrating on the history of anatomy, beginning with a first edition of Vesalius's De Humani Corporis Fabrica and holding many important and beautiful landmark volumes of anatomical atlases. PMID:27316691

  7. Ion implantation of silicon nitride ball bearings

    SciTech Connect

    Williams, J.M.; Miner, J.R.

    1996-09-01

    Hypothesis for ion implantation effect was that stress concentrations reflected into the bulk due to topography such as polishing imperfections, texture in the race, or transferred material, might be reduced due to surface amorphization. 42 control samples were tested to an intended runout period of 60 h. Six ion implanted balls were tested to an extended period of 150 h. Accelerated testing was done in a V groove so that wear was on two narrow wear tracks. Rutherford backscattering, XRPS, profilometry, optical microscopy, nanoindentation hardness, and white light interferometry were used. The balls were implanted with 150-keV C ions at fluence 1.1x10{sup 17}/cm{sup 2}. The samples had preexisting surface defects (C-cracks), so the failure rate of the control group was unacceptable. None of the ion-implanted samples failed in 150 h of testing. Probability of randomly selecting 6 samples from the control group that would perform this well is about 5%, so there is good probability that ion implantation improved performance. Possible reasons are discussed. Wear tracks, microstructure, and impurity content were studied in possible relation to C-cracks.

  8. One shot, one kill: the forces delivered by archer fish shots to distant targets.

    PubMed

    Burnette, Morgan F; Ashley-Ross, Miriam A

    2015-10-01

    Archer fishes are skillful hunters of terrestrial prey, firing jets of water that dislodge insects perched on overhead vegetation. In the current investigation, we sought an answer to the question: are distant targets impractical foraging choices? Targets far from the shooter might not be hit with sufficient force to cause them to fall. However, observations from other investigators show that archer fish fire streams of water that travel in a non-ballistic fashion, which is thought to keep on-target forces high, even to targets that are several body lengths distant from the fish. We presented targets at different distances and investigated three aspects of foraging behavior: (i) on-target forces, (ii) shot velocity, (iii) a two-target choice assay to determine if fish would show any preference for downing closer targets or more distant targets. In general, shots from our fish (Toxotes chatareus) showed a mild decrease (less than 15% on average) in on-target forces at our most distant target offered (5.8 body lengths) with respect to the closest target offered (2.3 body lengths). One individual in our investigation showed slightly, but significantly, greater on-target forces as target distance increased. Forces on the furthest targets offered were found to double that of attachment forces for 200mg insects, even for individuals whose on-target forces showed mild decreases with increases in target distance. High-speed video analysis of jet impact with the target revealed that the shot was traveling in a non-ballistic manner, even to our most distant target offered, corroborating previous suppositions that on-target forces should remain high. Fish were able to accomplish this without large changes to shot velocity, but we did find evidence that the water jets appeared to differ in the timing of their acceleration as target distance increased. Our two-target choice experiment revealed that fish show preference for downing the closer target first, even though impact

  9. Coherence and shot-to-shot spectral fluctuations in noise-like ultrafast fiber lasers.

    PubMed

    Runge, Antoine F J; Aguergaray, Claude; Broderick, Neil G R; Erkintalo, Miro

    2013-11-01

    We report on experimental studies of coherence and fluctuations in noise-like pulse trains generated by ultrafast fiber oscillators. By measuring the degree of first-order coherence using a Young's-type interference experiment, we prove the lack of phase coherence across the seemingly regular array of pulses. We further quantify the pulse-to-pulse fluctuations by recording the single-shot spectra of the megahertz pulse train, and experimentally demonstrate the existence of spectral fluctuations that remain unresolved in conventional time-averaged ensemble measurements. Phase incoherence and spectral fluctuations are contrasted with quantified coherence and spectral stability when the laser is soliton mode-locked. PMID:24177085

  10. Shots ESS through MET and Shot ZUCCHINI. The final TEAPOT tests, 23 March-15 May 1955. Technical report

    SciTech Connect

    Ponton, J.; Maag, C.; Wilkinson, M.; Rohrer, S.

    1981-11-27

    This report describes the activities of DOD personnel, both military and civilian, in Shots ESS, HADR, APPLE 1, WASP PRIME, HA, POST, MET, and ZUCCHINI, the latter eight events of the TEAPOT atmospheric nuclear weapons test series. Shot APPLE 2, the next to the last TEAPOT test event, is described in a separate volume. These tests were conducted from March 23 to May 15, 1955 and involved participants from Exercise Desert Rock VI, AFSWP, AFSWC, AEC nuclear weapons development laboratories, and the Civil Effects Test Group. This volume also describes the radiological safety activities undertaken at each shot.

  11. A similar shot to the previous image, this photograph, looking ...

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

    A similar shot to the previous image, this photograph, looking northwest, provides a closer image of the brick penthouse and other devices - Department of Energy, Mound Facility, Electronics Laboratory Building (E Building), One Mound Road, Miamisburg, Montgomery County, OH

  12. 21. Interior, view of shot corridor looking from the south ...

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

    21. Interior, view of shot corridor looking from the south to illustrate struyctural failure and a 15" shift - Fort Point, Gun Emplacement Number 1, 25 Wentworth Road, New Castle, Rockingham County, NH

  13. Introducing one-shot work into fluctuation relations

    NASA Astrophysics Data System (ADS)

    Yunger Halpern, Nicole; Garner, Andrew J. P.; Dahlsten, Oscar C. O.; Vedral, Vlatko

    2015-09-01

    Two approaches to small-scale and quantum thermodynamics are fluctuation relations and one-shot statistical mechanics. Fluctuation relations (such as Crooks’ theorem and Jarzynski's equality) relate nonequilibrium behaviors to equilibrium quantities such as free energy. One-shot statistical mechanics involves statements about every run of an experiment, not just about averages over trials. We investigate the relation between the two approaches. We show that both approaches feature the same notions of work and the same notions of probability distributions over possible work values. The two approaches are alternative toolkits with which to analyze these distributions. To combine the toolkits, we show how one-shot work quantities can be defined and bounded in contexts governed by Crooks’ theorem. These bounds provide a new bridge from one-shot theory to experiments originally designed for testing fluctuation theorems.

  14. 1. CONTEXT SHOT LOOKING NORTHWEST, WITH BUILDING 8250 (ARCH HANGAR) ...

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

    1. CONTEXT SHOT LOOKING NORTHWEST, WITH BUILDING 8250 (ARCH HANGAR) IN BACKGROUND. - Loring Air Force Base, Double Cantilever Hangar, East of Arizona Road, west of southern portion of Taxiway J, Limestone, Aroostook County, ME

  15. How one-shot learning unfolds in the brain.

    PubMed

    Weaver, Janelle

    2015-04-01

    Much learning occurs gradually through trial and error, but rare and important experiences require one-shot learning; a new study explores how the brain switches between these two strategies for identifying causal relationships. Read the Research Article. PMID:25919303

  16. [Effect of bending on shot peened and polished osteosynthesis plates].

    PubMed

    Starker, M; Fröhling, M; Hirsch, T

    1991-03-01

    Shot peening can increase the fatigue strength of commercially available surgical plates made of 1.4435 alloy by 40% even in a corrosive environment. Our investigations show that residual stresses resulting from shot peening are reduced by additional bending of the plates. In such plates smaller tensile residual stresses were found than after polishing of the plates. Bending of polished plates results in considerable tensile residual stresses. The hardening achieved by shot peening is not reduced by bending. As the fatigue strength of soft materials depends mainly on the hardening and less on the residual stresses, only little influence of the changed residual stresses on the fatigue strength can be expected. Shot peening of surgical implants thus means an improvement in quality. PMID:2054460

  17. 1. AERIAL SHOT HANGARS 14 (IN CENTER OF VIEW), WEST ...

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

    1. AERIAL SHOT HANGARS 1-4 (IN CENTER OF VIEW), WEST FACING, SIDE LOOKING EAST. BUILDING 100 IS IN FOREGROUND. - Hill Field, Airplane Repair Hangars No. 1-No. 4, 5875 Southgate Avenue, Layton, Davis County, UT

  18. 2. AERIAL SHOT HANGARS 14 (IN CENTER OF VIEW), SOUTH ...

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

    2. AERIAL SHOT HANGARS 1-4 (IN CENTER OF VIEW), SOUTH AND WEST FACING SIDES. BUILDING 238 IS IN LOWER RIGHT FOREGROUND. - Hill Field, Airplane Repair Hangars No. 1-No. 4, 5875 Southgate Avenue, Layton, Davis County, UT

  19. 8. DETAIL SHOT OF POST AND RAIL AND CUT AWAY ...

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

    8. DETAIL SHOT OF POST AND RAIL AND CUT AWAY VIEW OF ABUTMENT SUPPORT INTO THE GROUND - Lost Creek Road Bridge, Spanning Sevier River at County Road 243, 2 miles east of Aurora, Aurora, Sevier County, UT

  20. Interior, detail closeup shot of window with stained glass inserts ...

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

    Interior, detail closeup shot of window with stained glass inserts in top southeast room taken from ther west - J. Weingartner & Son Cigar Factory, 414 East Walnut Street, North Wales, Montgomery County, PA

  1. 26. OVERALL SHOT OF BASEMENT, MILL NO. 1. ORIGINALLY MACHINE ...

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

    26. OVERALL SHOT OF BASEMENT, MILL NO. 1. ORIGINALLY MACHINE SHOP. PALLETS ON FLOOR ADDED IN LATE 20th C. FOR CLOTH STORAGE. - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

  2. Shot noise in an electron waveguide {radical}(NOT) gate

    SciTech Connect

    Reichl, Linda E.; Snyder, Michael G.

    2006-07-15

    We present a calculation of the shot noise in a ballistic electron waveguide {radical}(NOT) gate. A general expression for the shot noise in the leads connected to these types of gates is shown. We then parametrize an S-matrix which qualitatively describes the action of a {radical}(NOT) gate previously found through numerical methods for GaAs/Al{sub x}Ga{sub 1-x}As based waveguide systems. Using this S-matrix, the shot noise in a single output lead and across two output leads is calculated. We find that the measurement of the shot noise across two output leads allows for the determination of the fidelity of the gate itself.

  3. Pregnancy Flu Shot Protects Newborn for 8 Weeks: Study

    MedlinePlus

    ... html Pregnancy Flu Shot Protects Newborn for 8 Weeks: Study Effectiveness drops dramatically after that To use ... protection is likely limited to the first eight weeks of life, said Marta Nunes, of the University ...

  4. Shot noise measurement in a strongly correlated material

    NASA Astrophysics Data System (ADS)

    Zhou, Panpan; Hardy, Will; Cho, Ethan; Cybart, Shane; Dynes, Robert; Natelson, Douglas

    In strongly correlated materials, the motion of an electron is strongly affected by interactions with other electrons, leading to many interesting phenomena including metal-insulator transitions, colossal magnetoresistance, and high temperature superconductivity. Shot noise is one experimental probe for electronic correlations beyond simple electronic transport. Shot noise, which originates from the discrete nature of the charge-carrying particles, can be strongly affected by electronic correlations. Here we report initial shot noise measurements in tunnel junctions prepared from a YBa2Cu3O7-x film sample, with nanoscale junctions written by focused helium ion beam. We will discuss a comparison of the shot noise between the YBCO film sample and standard tunnel junctions, as a function of temperature and bias, and the implications of these results.

  5. SunShot Vision Study: February 2012 (Book)

    SciTech Connect

    Not Available

    2012-02-01

    The objective of the SunShot Vision Study is to provide an in-depth assessment of the potential for solar technologies to meet a significant share of electricity demand in the United States during the next several decades. Specifically, it explores a future in which the price of solar technologies declines by about 75% between 2010 and 2020 - in line with the U.S. Department of Energy (DOE) SunShot Initiative's targets.

  6. Grid Modeling for the SunShot Vision Study

    SciTech Connect

    Brinkman, G.; Denholm, P.; Drury, E.; Ela, E.; Mai, T.; Margolis, R.; Mowers, M.

    2012-02-01

    This document describes the use of production cost modeling in the SunShot Vision study, including methods used to create the SunShot Vision scenarios, their implementation in the Gridview model, and assumptions regarding transmission system and operation of each generator type. It also describes challenges and limitations of modeling solar generation technologies in production cost models, and suggests methods for improving their representation in current models.

  7. SnapShot: SMC Protein Complexes Part II.

    PubMed

    Haering, Christian H; Gruber, Stephan

    2016-02-11

    This second of two SnapShots on SMC proteins depicts their roles at different stages of the eukaryotic cell cycle. The composition and architecture of SMC protein complexes and their regulators appear in SMC Protein Complexes Part I (available at http://www.cell.com/cell/pdf/S0092-8674%2815%2901690-6.pdf). To view this SnapShot, open or download the PDF. PMID:26871638

  8. Experimental lead-shot poisoning in bald eagles

    USGS Publications Warehouse

    Pattee, O.H.; Wiemeyer, Stanley N.; Mulhern, B.M.; Sileo, L.; Carpenter, J.W.

    1981-01-01

    Captive, crippled bald eagles unsuitable for release were fed lead shot to determine diagnostic criteria for lead poisoning. The eagles were fluoroscoped and bled periodically to determine shot retention and blood delta--aminolevulinic acid dehydratase activity. Microscopic examination revealed renal tubular degeneration, arterial fibrinoid necrosis and myocardial necrosis. Acid-fast intra-nuclear inclusion bodies were not found in proximal convoluted tubule cells. Analyses of blood and toxicological data are not yet complete.

  9. Learning to See the Ball Using the Alexander Technique

    ERIC Educational Resources Information Center

    Gosselin, Gaynelle

    2011-01-01

    This article begins with a personal anecdote from the author, for whom childhood P.E. classes were exercises in frustration and humiliation largely because she could not master the coordination needed to catch, throw, or hit a ball. She could not keep her eye on the ball despite well-meaning instruction from coaches, friends, and family members.…

  10. Ball-Stick-Bird: Teaching with the Story Engram.

    ERIC Educational Resources Information Center

    Fuller, Renee

    1990-01-01

    This paper describes the Ball-Stick-Bird reading system, which shows students how all the letters of the alphabet can be built with three basic forms: a circle (ball), a line (stick), and an angle (bird). The method also uses modified phonics and developmental linguistics, aids story reading by using capital letters in the beginning, and enhances…

  11. Machine finishes balls to high degree of roundness

    NASA Technical Reports Server (NTRS)

    Angele, W.; Hill, J. P., Jr.

    1972-01-01

    Machine was developed to finish ball to roundness within 12.5 nm (half a microinch) from any types of hard material. Grinding and polishing to this tolerance is accomplished by lapping elements on four to six motor-driven spindles. Spindles are adjustably spring-loaded to ensure constant contact pressure on ball and are driven by variable speed electric motors.

  12. Segmented ball valve is easy to open and close

    NASA Technical Reports Server (NTRS)

    Prono, E.; Shinault, L. H.; Speisman, C.

    1966-01-01

    Segmented ball valve and flowmeter in the same spherical housing provide a valve that will handle large fluid volume without bulkiness and weight of blade valves or conventional ball valves. The valve is easily opened or closed and the flowmeter remains stationary, so errors are eliminated.

  13. Physical Activity Benefits Creativity: Squeezing a Ball for Enhancing Creativity

    ERIC Educational Resources Information Center

    Kim, JongHan

    2015-01-01

    Studies in embodied cognition show that physical sensations, such as touch and movement, influence cognitive processes. Two studies were conducted to test whether squeezing a soft versus a hard ball facilitates different types of creativity. Squeezing a malleable ball would increase divergent creativity by catalyzing multiple or alternative ideas,…

  14. Launch Creativity with Ping-Pong Ball Challenge

    ERIC Educational Resources Information Center

    Kornoelje, Joanne; Roman, Harry T.

    2011-01-01

    Educators at Thomas A. Edison Middle School have worked together to bring invention information and activities to life. One activity in particular, Ping-Pong Ball Invention Challenge, has proven a great success. The Ping-Pong Ball Invention Challenge was inspired by the basic rules for PBS's "Design Squad"'s "Pop Fly" activity. In this article,…

  15. Motion of a Ball on a Moving Surface

    ERIC Educational Resources Information Center

    Cross, Rod

    2016-01-01

    A well-known physics demonstration is to pull a tablecloth rapidly from under some crockery without disturbing the crockery. An interesting question is whether the same result can be expected if the crockery is replaced by a ball, given that the ball might roll backwards on the tablecloth. Theoretical and experimental results are presented showing…

  16. Hardening treatment of friction surfaces of ball journal bearings

    NASA Astrophysics Data System (ADS)

    Gorlenko, A. O.; Davidov, S. V.

    2016-04-01

    The article presents the technology of finishing plasma hardening by the application of the multi-layer nanocoating Si-O-C-N system to harden the friction surfaces of the ball journal bearings. The authors of the paper have studied the applied wear-resistant anti-friction coating tribological characteristics, which determine the increase in wear resistance of the ball journal bearings.

  17. Forces Acting on a Ball in an Air Jet

    ERIC Educational Resources Information Center

    Lopez-Arias, T.; Gratton, L. M.; Zendri, G.; Oss, S.

    2011-01-01

    The forces acting on a ball in an air jet have been measured using simple equipment. Such measurements allow quite a precise, non-ambiguous description and understanding of the physical mechanism which explains the famous levitating ball experiment. (Contains 7 figures.)

  18. The Net Physiological Cost of Dribbling a Soccer Ball.

    ERIC Educational Resources Information Center

    Reilly, Thomas; Ball, David

    1984-01-01

    To establish the net energy cost of dribbling a soccer ball, eight males ran on a treadmill while dribbling a ball against a rebound box. Oxygen uptake, perceived exertion, and blood lactate levels were measured and compared with results from subjects running without dribbling. Results are discussed. (Author/DF)

  19. [First clinical experiences with ceramic ball attachments for overdentures].

    PubMed

    Büttel, Adrian E; Schmidli, Fredy; Marinello, Carlo P; Lüthy, Heinz

    2008-01-01

    In this prospective clinical study on 40 patients with similar clinical conditions (edentulous jaw with 2 interforaminal implants) commercially available ceramic ball attachments (ruby) were compared to commercial titanium ball attachments. The primary aim of the study was to measure the wear of the ball attachments after being 1 year in function. However, in the course of the study already after 7 to 12 months multiple failures with ceramic ball attachments occurred. Twelve (28%) of 43 ceramic ball attachments had to be replaced, mostly because of fractures (8) of the ceramic ball. It seems that ceramic ball attachments of the investigated design are not able to withstand normal intraoral stresses. The short-term susceptibility to fractures didn't allow to examine the ceramic-inherent features such as compressive strength and wear resistance. Furthermore, a secure connection between a titan base and a ceramic ball seems to be challenging. Based on these results, in implant-retained removable prosthesis the use of metal-based retainers is still recommended, although during maintenance a higher wear has to be expected. This wear can be compensated by either activating or changing the matrix or the patrix. PMID:18293602

  20. Why Low Bounce Balls Exhibit High Rolling Resistance

    ERIC Educational Resources Information Center

    Cross, Rod

    2015-01-01

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

  1. Dynamics of Q-balls in an expanding universe

    SciTech Connect

    Palti, Eran; Saffin, P.M.; Copeland, E.J.

    2004-10-15

    We analyze the evolution of light Q-balls in a cosmological background, and find a number of interesting features. For Q-balls formed with a size comparable to the Hubble radius, we demonstrate that there is no charge radiation, and that the Q-ball maintains a constant physical radius. Large expansion rates cause charge migration to the surface of the Q-ball, corresponding to a nonhomogeneous internal rotation frequency. We argue that this is an important phenomenon as it leads to a large surface charge and possible fragmentation of the Q-ball. We also explore the deviation of the Q-ball profile function from the static case. By introducing a parameter {epsilon}, which is the ratio of the Hubble parameter to the frequency of oscillation of the Q-ball field, and using solutions to an analytically approximated equation for the profile function, we determine the dependence of the new features on the expansion rate. This allows us to gain an understanding of when they should be considered and when they can be neglected, thereby placing restrictions on the existence of homogeneous Q-balls in expanding backgrounds.

  2. Between Traditions: Stephen Ball and the Critical Sociology of Education

    ERIC Educational Resources Information Center

    Apple, Michael W.

    2013-01-01

    Stephen Ball's work has deservedly received a good deal of attention. In this article, I detail a number of tasks in which the critical sociologist of education--as a "public intellectual"--should engage. I then place Ball's work within these tasks and evaluate his contributions to them. In the process, I show that one of the…

  3. Exact solutions, energy, and charge of stable Q-balls

    NASA Astrophysics Data System (ADS)

    Bazeia, D.; Marques, M. A.; Menezes, R.

    2016-05-01

    In this work we deal with nontopological solutions of the Q-ball type in two spacetime dimensions. We study models of current interest, described by a Higgs-like and other, similar potentials which unveil the presence of exact solutions. We use the analytic results to investigate how to control the energy and charge to make the Q-balls stable.

  4. Organic matter in a coal ball: Peat or coal?

    USGS Publications Warehouse

    Hatcher, P.G.; Lyons, P.C.; Thompson, C.L.; Brown, F.W.; Maciel, G.E.

    1982-01-01

    Chemical analyses of morphologically preserved organic matter in a Carboniferous coal ball reveal that the material is coalified to a rank approximately equal to that of the surrounding coal. Hence, the plant tissues in the coal ball were chemically altered by coalification processes and were not preserved as peat. Copyright ?? 1982 AAAS.

  5. On a Simple Formulation of the Golf Ball Paradox

    ERIC Educational Resources Information Center

    Pujol, O.; Perez, J. Ph.

    2007-01-01

    The motion of a ball rolling without slipping on the lateral section inside a fixed vertical cylinder is analysed in the Earth referential frame which is assumed to be Galilean. Equations of motion are rapidly obtained and the golf ball paradox is understood: these equations describe a motion consisting of a vertical harmonic oscillation related…

  6. Optical Trajectories and the Informational Basis of Fly Ball Catching

    ERIC Educational Resources Information Center

    Marken, Richard S.

    2005-01-01

    D. M. Shaffer and M. K. McBeath (see record 2002-02027-006) plotted the optical trajectories of uncatchable fly balls and concluded that linear optical trajectory is the informational basis of the actions taken to catch these balls. P. McLeod, N. Reed, and Z. Dienes (see record 2002-11140-016) replotted these trajectories in terms of changes in…

  7. A Measurement of "g" Listening to Falling Balls

    ERIC Educational Resources Information Center

    White, J. A.; Medina, A.; Roman, F. L.; Velasco, S.

    2007-01-01

    A ball placed on the edge of a horizontal table is hit with a pendulum and thrown over the floor. The fall time is measured by recording the sounds produced by the collisions with the pendulum and the floor. If the height of the ball with respect to the floor is known, one can determine the acceleration of gravity.

  8. Modelling the Projectile Motion of a Cricket Ball.

    ERIC Educational Resources Information Center

    Coutis, Peter

    1998-01-01

    Presents the equations of motion governing the trajectory of a cricket ball subject to a linear drag force. Uses a perturbation expansion technique to solve the resulting trajectory equation for the range of a cricket ball struck into the outfield. (Author/ASK)

  9. A systematic study of ball passing frequencies based on dynamic modeling of rolling ball bearings with localized surface defects

    NASA Astrophysics Data System (ADS)

    Niu, Linkai; Cao, Hongrui; He, Zhengjia; Li, Yamin

    2015-11-01

    Ball passing frequencies (BPFs) are very important features for condition monitoring and fault diagnosis of rolling ball bearings. The ball passing frequency on outer raceway (BPFO) and the ball passing frequency on inner raceway (BPFI) are usually calculated by two well-known kinematics equations. In this paper, a systematic study of BPFs of rolling ball bearings is carried out. A novel method for accurately calculating BPFs based on a complete dynamic model of rolling ball bearings with localized surface defects is proposed. In the used dynamic model, three-dimensional motions, relative slippage, cage effects and localized surface defects are all considered. Moreover, localized surface defects are modeled accurately with consideration of the finite size of the ball, the additional clearance due to material absence, and changes of contact force directions. The reasonability of the proposed method for the prediction of dynamic behaviors of actual ball bearings with localized surface defects and for the calculation of BPFs is discussed by investigating the motion characteristics of a ball when it rolls through a defect. Parametric investigation shows that the shaft speed, external loads, the friction coefficient, raceway groove curvature factors, the initial contact angle, and defect sizes have great effects on BPFs. For a loaded ball bearing, the combination of rolling and sliding in contact region occurs, and the BPFs calculated by simple kinematical relationships are inaccurate, especially for high speed, low external load, and large initial contact angle conditions where severe skidding occurs. The hypothesis that the percentage variation of the spacing between impulses in a defective ball bearing was about 1-2% reported in previous investigations can be satisfied only for the conditions where the skidding effect in a bearing is slight. Finally, the proposed method is verified with two experiments.

  10. Ball Screw Actuator Including an Axial Soft Stop

    NASA Technical Reports Server (NTRS)

    Wingett, Paul T. (Inventor); Forrest, Steven Talbert (Inventor); Abel, Steve (Inventor); Woessner, George (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.

  11. Kinematics analysis on the shot putting technique of back gliding of China's female shot putters

    NASA Astrophysics Data System (ADS)

    Hui, Zhongtao

    2012-04-01

    In this paper, Shanghai female shot-putter Shou Qianwen was selected as the research object, and also the methods in the biological mechanics were used to analyze and research her movements of shot putting techniques. As a result, at the sliding step stage, the maximum swinging velocity of her left leg emerged too early, the joint between the take-off and swinging techniques was not very ideal, and the angle between the calf and the ground when the right leg departed from the ground was too large. However, at the transition step stage, the body weight velocity fluctuated too largely, and its single support time was too long. At the final exertion stage, the posture of her body before the apparatus was highly sufficient, but the exertion movement of the body was too hasty, and the hip movements were insufficient, which was reflected on that the exertion point was not prominent, the acceleration effect was insignificant, and the shooting speed was not very fast, and also the shooting angle was too low.

  12. 77 FR 59158 - Migratory Bird Hunting; Application for Approval of Copper-Clad Iron Shot and Fluoropolymer Shot...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-26

    ... cladding up to 44.1 of the shot mass. Tungsten-bronze 51.1 tungsten, 44.4 copper, Rare Earth Magnet. 3.9........... 40-76 tungsten, 10-37 iron, Hot Shot or Rare Earth Magnet. 9-16 copper, and 5-7 nickel. Tungsten.... Tungsten-tin-bismuth any proportions of Rare Earth Magnet. tungsten, tin, and bismuth....

  13. Ball-scale based hierarchical multi-object recognition in 3D medical images

    NASA Astrophysics Data System (ADS)

    Bağci, Ulas; Udupa, Jayaram K.; Chen, Xinjian

    2010-03-01

    This paper investigates, using prior shape models and the concept of ball scale (b-scale), ways of automatically recognizing objects in 3D images without performing elaborate searches or optimization. That is, the goal is to place the model in a single shot close to the right pose (position, orientation, and scale) in a given image so that the model boundaries fall in the close vicinity of object boundaries in the image. This is achieved via the following set of key ideas: (a) A semi-automatic way of constructing a multi-object shape model assembly. (b) A novel strategy of encoding, via b-scale, the pose relationship between objects in the training images and their intensity patterns captured in b-scale images. (c) A hierarchical mechanism of positioning the model, in a one-shot way, in a given image from a knowledge of the learnt pose relationship and the b-scale image of the given image to be segmented. The evaluation results on a set of 20 routine clinical abdominal female and male CT data sets indicate the following: (1) Incorporating a large number of objects improves the recognition accuracy dramatically. (2) The recognition algorithm can be thought as a hierarchical framework such that quick replacement of the model assembly is defined as coarse recognition and delineation itself is known as finest recognition. (3) Scale yields useful information about the relationship between the model assembly and any given image such that the recognition results in a placement of the model close to the actual pose without doing any elaborate searches or optimization. (4) Effective object recognition can make delineation most accurate.

  14. Resonant frequency method for bearing ball inspection

    DOEpatents

    Khuri-Yakub, B.T.; Chungkao Hsieh.

    1993-11-02

    The present invention provides for an inspection system and method for detecting defects in test objects which includes means for generating expansion inducing energy focused upon the test object at a first location, such expansion being allowed to contract, thereby causing pressure wave within and on the surface of the test object. Such expansion inducing energy may be provided by, for example, a laser beam or ultrasonic energy. At a second location, the amplitudes and phases of the acoustic waves are detected and the resonant frequencies' quality factors are calculated and compared to predetermined quality factor data, such comparison providing information of whether the test object contains a defect. The inspection system and method also includes means for mounting the bearing ball for inspection. 5 figures.

  15. Recent results from the Crystal Ball

    SciTech Connect

    Porter, F.C.

    1981-09-01

    During the past year, the Crystal Ball experiment has continued the investigation of e/sup +/e/sup -/ interactions at SPEAR. In the course of the year, we have slightly more than doubled the available datasets at the J/psi (to 2.2 x 10/sup 6/ produced J/psi) and the psi' (to 1.8 x 10/sup 6/ produced psi') resonances, and have increased the data in the 5.2 to 7.4 GeV center-of-mass (E/sub c.m./) region. The present discussion is limited to recent results obtained with the J/psi and psi' datasets, primarily dealing with transitions among the charmonium bound states.

  16. Neutron detection using a crystal ball calorimeter

    NASA Astrophysics Data System (ADS)

    Martem'yanov, M. A.; Kulikov, V. V.; Krutenkova, A. P.

    2015-12-01

    The program of experiments of the A2 Collaboration performed on a beam of tagged photons of the MAMI electron microtron in Mainz (Germany) includes precision measurements of the total and differential cross sections of the pion photoproduction on neutrons of a deuterium target. The determination of the detector ability to detect neutrons is undoubtedly one of the important problems of the experiment. The calorimetric system of the detector contains a segmented NaI Crystal Ball detector, which gives information about the position, energy, and detection time of neutral and charged particles in a wide angular range. In this work, we describe the measurement of the neutron detection efficiency in the energy range from 20 to 400MeV. The results are compared with BNL data obtained on a pion beam and proton target.

  17. Grinding arrangement for ball nose milling cutters

    NASA Technical Reports Server (NTRS)

    Burch, C. F. (Inventor)

    1974-01-01

    A grinding arrangement for spiral fluted ball nose end mills and like tools includes a tool holder for positioning the tool relative to a grinding wheel. The tool is mounted in a spindle within the tool holder for rotation about its centerline and the tool holder is pivotably mounted for angular movement about an axis which intersects that centerline. A follower arm of a cam follower secured to the spindle cooperates with a specially shaped cam to provide rotation of the tool during the angular movement of the tool holder during the grinding cycle, by an amount determined by the cam profile. In this way the surface of the cutting edge in contact with the grinding wheel is maintained at the same height on the grinding wheel throughout the angular movement of the tool holder during the grinding cycle.

  18. Hot balls splash and sink fast

    NASA Astrophysics Data System (ADS)

    Marston, Jeremy; Vakarelski, Ivan; Thoroddsen, Sigurdur; Chan, Derek

    2011-11-01

    When a heated sphere is immersed in a liquid, we induce an inverted Leidenfrost effect whereby the sphere is wrapped in a vapour jacket which protects it from physical contact with the liquid and, when released to fall freely in the liquid, the sphere's terminal velocity can increase dramatically compared to a cold ball. This Leidenfrost-induced vapour layer can lead to significant drag reduction by up to 85% which appears to be the limiting case for drag reduction techniques based on gas layer injection. In a related experiment, when the heated sphere is released from above the surface, the dynamics of the entry are significantly different from the cold case, resulting in a prompt splash and cavity formation. We propose that this experiment is the ultimate non-wetting scenario during water-entry problems.

  19. Resonant frequency method for bearing ball inspection

    DOEpatents

    Khuri-Yakub, B. T.; Hsieh, Chung-Kao

    1993-01-01

    The present invention provides for an inspection system and method for detecting defects in test objects which includes means for generating expansion inducing energy focused upon the test object at a first location, such expansion being allowed to contract, thereby causing pressure wave within and on the surface of the test object. Such expansion inducing energy may be provided by, for example, a laser beam or ultrasonic energy. At a second location, the amplitudes and phases of the acoustic waves are detected and the resonant frequencies' quality factors are calculated and compared to predetermined quality factor data, such comparison providing information of whether the test object contains a defect. The inspection system and method also includes means for mounting the bearing ball for inspection.

  20. Flame balls - Past, present and future

    NASA Technical Reports Server (NTRS)

    Buckmaster, J.; Ronney, P.; Smooke, M.

    1993-01-01

    This paper discusses analytical and numerical work that has been carried out in order to understand flame-balls and related phenomena that have been observed in microgravity experiments. The importance of heat losses is identified, whether from conduction, convection, or radiation. Accurate numerical simulations for hydrogen-air mixtures with radiation losses reveal a flammability limit of 3.5 percent of hydrogen by volume, a value close to the experimental one. The important role of stability analyses is emphasized, with particular attention to the role of three-dimensional instabilities in explaining unsteady spheroidal flames and flame-strings, objects that are observed in the experiments. We speculate that the dynamics of flame-strings is affected by in-depth radiation absorption for mixtures containing SF6, and report on some preliminary calculations in which this phenomenon is accounted for.

  1. Neutron detection using a crystal ball calorimeter

    SciTech Connect

    Martem’yanov, M. A. Kulikov, V. V.; Krutenkova, A. P.

    2015-12-15

    The program of experiments of the A2 Collaboration performed on a beam of tagged photons of the MAMI electron microtron in Mainz (Germany) includes precision measurements of the total and differential cross sections of the pion photoproduction on neutrons of a deuterium target. The determination of the detector ability to detect neutrons is undoubtedly one of the important problems of the experiment. The calorimetric system of the detector contains a segmented NaI Crystal Ball detector, which gives information about the position, energy, and detection time of neutral and charged particles in a wide angular range. In this work, we describe the measurement of the neutron detection efficiency in the energy range from 20 to 400MeV. The results are compared with BNL data obtained on a pion beam and proton target.

  2. Estimating Neuronal Ageing with Hidden Markov Models

    NASA Astrophysics Data System (ADS)

    Wang, Bing; Pham, Tuan D.

    2011-06-01

    Neuronal degeneration is widely observed in normal ageing, meanwhile the neurode-generative disease like Alzheimer's disease effects neuronal degeneration in a faster way which is considered as faster ageing. Early intervention of such disease could benefit subjects with potentials of positive clinical outcome, therefore, early detection of disease related brain structural alteration is required. In this paper, we propose a computational approach for modelling the MRI-based structure alteration with ageing using hidden Markov model. The proposed hidden Markov model based brain structural model encodes intracortical tissue/fluid distribution using discrete wavelet transformation and vector quantization. Further, it captures gray matter volume loss, which is capable of reflecting subtle intracortical changes with ageing. Experiments were carried out on healthy subjects to validate its accuracy and robustness. Results have shown its ability of predicting the brain age with prediction error of 1.98 years without training data, which shows better result than other age predition methods.

  3. Hidden variables and nonlocality in quantum mechanics

    NASA Astrophysics Data System (ADS)

    Hemmick, Douglas Lloyd

    1997-05-01

    Most physicists hold a skeptical attitude toward a 'hidden variables' interpretation of quantum theory, despite David Bohm's successful construction of such a theory and John S. Bell's strong arguments in favor of the idea. The first reason for doubt concerns certain mathematical theorems (von Neumann's, Gleason's, Kochen and Specker's, and Bell's) which can be applied to the hidden variables issue. These theorems are often credited with proving that hidden variables are indeed 'impossible', in the sense that they cannot replicate the predictions of quantum mechanics. Many who do not draw such a strong conclusion nevertheless accept that hidden variables have been shown to exhibit prohibitively complicated features. The second concern is that the most sophisticated example of a hidden variables theory-that of David Bohm-exhibits non-locality, i.e., consequences of events at one place can propagate to other places instantaneously. However, neither the mathematical theorems in question nor the attribute of nonlocality detract from the importance of a hidden variables interpretation of quantum theory. Nonlocality is present in quantum mechanics itself, and is a required characteristic of any theory that agrees with the quantum mechanical predictions. We first discuss the earliest analysis of hidden variables-that of von Neumann's theorem-and review John S. Bell's refutation of von Neumann's 'impossibility proof'. We recall and elaborate on Bell's arguments regarding the theorems of Gleason, and Kochen and Specker. According to Bell, these latter theorems do not imply that hidden variables interpretations are untenable, but instead that such theories must exhibit contextuality, i.e., they must allow for the dependence of measurement results on the characteristics of both measured system and measuring apparatus. We demonstrate a new way to understand the implications of both Gleason's theorem and Kochen and Specker's theorem by noting that they prove a result we call

  4. Hidden SU (N ) glueball dark matter

    NASA Astrophysics Data System (ADS)

    Soni, Amarjit; Zhang, Yue

    2016-06-01

    We investigate the possibility that the dark matter candidate is from a pure non-Abelian gauge theory of the hidden sector, motivated in large part by its elegance and simplicity. The dark matter is the lightest bound state made of the confined gauge fields, the hidden glueball. We point out that this simple setup is capable of providing rich and novel phenomena in the dark sector, especially in the parameter space of large N . They include self-interacting and warm dark matter scenarios, Bose-Einstein condensation leading to massive dark stars possibly millions of times heavier than our sun giving rise to gravitational lensing effects, and indirect detections through higher dimensional operators as well as interesting collider signatures.

  5. Multiple alignment using hidden Markov models

    SciTech Connect

    Eddy, S.R.

    1995-12-31

    A simulated annealing method is described for training hidden Markov models and producing multiple sequence alignments from initially unaligned protein or DNA sequences. Simulated annealing in turn uses a dynamic programming algorithm for correctly sampling suboptimal multiple alignments according to their probability and a Boltzmann temperature factor. The quality of simulated annealing alignments is evaluated on structural alignments of ten different protein families, and compared to the performance of other HMM training methods and the ClustalW program. Simulated annealing is better able to find near-global optima in the multiple alignment probability landscape than the other tested HMM training methods. Neither ClustalW nor simulated annealing produce consistently better alignments compared to each other. Examination of the specific cases in which ClustalW outperforms simulated annealing, and vice versa, provides insight into the strengths and weaknesses of current hidden Maxkov model approaches.

  6. Extended abstract of a hidden agenda

    SciTech Connect

    Goguen, J.; Malcolm, G.

    1996-12-31

    The initial goal of our hidden research programme was both straightforward and ambitious: give a semantics for software engineering, and in particular for the object paradigm, supporting correctness proofs that are as simple and mechanical as possible. This emphasizes proofs rather than models, and thus suggests an equational approach, rather than one based on higher order logic, denotational semantics, or any kind of model, because equational proofs achieve maximal simplicity and mechanization, and yet are fully expressive. We introduce powerful coinduction techniques for proving behavioral properties of complex systems. We make the no doubt outrageous claim that our hidden approach gives simpler proofs than other formalisms; this is because we exploit algebraic structure that most other approaches discard.

  7. Hydraulic-Leak Detector for Hidden Joints

    NASA Technical Reports Server (NTRS)

    Anderson, G. E.; Loo, S.

    1986-01-01

    Slow leakage of fluid made obvious. Indicator consists of wick wrapped at one end around joint to be monitored. Wick absorbs hydraulic fluid leaking from joint and transmits to opposite end, located outside cover plate and visible to inspector. Leakage manifested as discoloration of outside end of wick. Indicator reveals leaks in hidden fittings on hydraulic lines. Fast inspection of joints without disassembly. Used in aerospace, petroleum, chemical, nuclear, and other industries where removing covers for inspection impossible, difficult, or time-consuming.

  8. Motor adaptation in complex sports - the influence of visual context information on the adaptation of the three-point shot to altered task demands in expert basketball players.

    PubMed

    Stöckel, Tino; Fries, Udo

    2013-01-01

    We examined the influence of visual context information on skilled motor behaviour and motor adaptation in basketball. The rules of basketball in Europe have recently changed, such that that the distance for three-point shots increased from 6.25 m to 6.75 m. As such, we tested the extent to which basketball experts can adapt to the longer distance when a) only the unfamiliar, new three-point line was provided as floor markings (NL group), or b) the familiar, old three-point line was provided in addition to the new floor markings (OL group). In the present study 20 expert basketball players performed 40 three-point shots from 6.25 m and 40 shots from 6.75 m. We assessed the percentage of hits and analysed the landing position of the ball. Results showed better adaptation of throwing performance to the longer distance when the old three-point line was provided as a visual landmark, compared to when only the new three-point line was provided. We hypothesise that the three-point line delivered relevant information needed to successfully adapt to the greater distance in the OL group, whereas it disturbed performance and ability to adapt in the NL group. The importance of visual landmarks on motor adaptation in basketball throwing is discussed relative to the influence of other information sources (i.e. angle of elevation relative to the basket) and sport practice. PMID:23215863

  9. Hidden Markov Model Analysis of Multichromophore Photobleaching

    PubMed Central

    Messina, Troy C.; Kim, Hiyun; Giurleo, Jason T.; Talaga, David S.

    2007-01-01

    The interpretation of single-molecule measurements is greatly complicated by the presence of multiple fluorescent labels. However, many molecular systems of interest consist of multiple interacting components. We investigate this issue using multiply labeled dextran polymers that we intentionally photobleach to the background on a single-molecule basis. Hidden Markov models allow for unsupervised analysis of the data to determine the number of fluorescent subunits involved in the fluorescence intermittency of the 6-carboxy-tetramethylrhodamine labels by counting the discrete steps in fluorescence intensity. The Bayes information criterion allows us to distinguish between hidden Markov models that differ by the number of states, that is, the number of fluorescent molecules. We determine information-theoretical limits and show via Monte Carlo simulations that the hidden Markov model analysis approaches these theoretical limits. This technique has resolving power of one fluorescing unit up to as many as 30 fluorescent dyes with the appropriate choice of dye and adequate detection capability. We discuss the general utility of this method for determining aggregation-state distributions as could appear in many biologically important systems and its adaptability to general photometric experiments. PMID:16913765

  10. Extracting hidden messages in steganographic images

    DOE PAGESBeta

    Quach, Tu-Thach

    2014-07-17

    The eventual goal of steganalytic forensic is to extract the hidden messages embedded in steganographic images. A promising technique that addresses this problem partially is steganographic payload location, an approach to reveal the message bits, but not their logical order. It works by finding modified pixels, or residuals, as an artifact of the embedding process. This technique is successful against simple least-significant bit steganography and group-parity steganography. The actual messages, however, remain hidden as no logical order can be inferred from the located payload. This paper establishes an important result addressing this shortcoming: we show that the expected mean residualsmore » contain enough information to logically order the located payload provided that the size of the payload in each stego image is not fixed. The located payload can be ordered as prescribed by the mean residuals to obtain the hidden messages without knowledge of the embedding key, exposing the vulnerability of these embedding algorithms. We provide experimental results to support our analysis.« less

  11. Extracting hidden messages in steganographic images

    SciTech Connect

    Quach, Tu-Thach

    2014-07-17

    The eventual goal of steganalytic forensic is to extract the hidden messages embedded in steganographic images. A promising technique that addresses this problem partially is steganographic payload location, an approach to reveal the message bits, but not their logical order. It works by finding modified pixels, or residuals, as an artifact of the embedding process. This technique is successful against simple least-significant bit steganography and group-parity steganography. The actual messages, however, remain hidden as no logical order can be inferred from the located payload. This paper establishes an important result addressing this shortcoming: we show that the expected mean residuals contain enough information to logically order the located payload provided that the size of the payload in each stego image is not fixed. The located payload can be ordered as prescribed by the mean residuals to obtain the hidden messages without knowledge of the embedding key, exposing the vulnerability of these embedding algorithms. We provide experimental results to support our analysis.

  12. Lepton mixing from the hidden sector

    NASA Astrophysics Data System (ADS)

    Ludl, P. O.; Smirnov, A. Yu.

    2015-10-01

    Experimental results indicate a possible relation between the lepton and quark mixing matrices of the form UPMNS≈VCKM†UX , where UX is a matrix with special structure related to the mechanism of neutrino mass generation. We propose a framework which can realize such a relation. The main ingredients of the framework are the double seesaw mechanism, SO(10) grand unification and a hidden sector of theory. The latter is composed of singlets (fermions and bosons) of the grand unified theory (GUT) symmetry with masses between the GUT and Planck scale. The interactions in this sector obey certain symmetries Ghidden. We explore the conditions under which symmetries Ghidden can produce flavor structures in the visible sector. Here the key elements are the basis-fixing symmetry and mediators which communicate information about properties of the hidden sector to the visible one. The interplay of SO(10) symmetry, basis-fixing symmetry identified as Z2×Z2 and Ghidden can lead to the required form of UX. A different kind of new physics is responsible for generation of the CKM mixing. We present the simplest realizations of the framework which differ by nature of the mediators and by symmetries of the hidden sector.

  13. The ecotoxicology of lead shot and lead fishing weights.

    PubMed

    Scheuhammer, A M; Norris, S L

    1996-10-01

    : Lead shot ingestion is the primary source of elevated lead exposure and poisoning in waterfowl and most other bird species. For some species (e.g. Common Loons, Gavia immer), lead sinker ingestion is a more frequent cause of lead poisoning. In freshwater environments where recreational angling activity and loon populations co-occur, lead poisoning from ingestion of small (<50 gram) lead sinkers or jigs accounts for 10-50% of recorded adult loon mortality, depending on the locations studied. Lead shot ingestion occurs in waterfowl, and in a wide variety of non-waterfowl species, including upland game birds, shorebirds, raptors, and scavengers. Where it has been explicitly studied in Canada and the US, lead poisoning mortality of bald (Haliacetus leucocephalus) and golden eagles (Aquila chrysactos) from eating prey animals with lead shot embedded in their tissues accounts for an estimated 10-15% of the recorded post-fledging mortality in these raptorial species. In addition to environments that experience hunting with lead shot, clay target shooting ranges, especially those in which the shotfall zones include ponds, marshes, lakes, rivers, beaches, or other aquatic-type environments, create a significant risk of shot ingestion and poisoning for waterbirds. Metallic lead pellets deposited onto soils and aquatic sediments are not chemically or environmentally inert, although tens or hundreds of years may be required for total breakdown and dissolution of pellets. Functional, affordable non-toxic alternatives to lead shot and sinkers are being currently produced, and additional such products are being developed. Several countries have successfully banned the use of small lead sinkers, and of lead shot for waterfowl and other hunting, also for clay target shooting, using a phasing-out process that gives manufactures, sellers, and users adequate time to adjust to the regulations. PMID:24193869

  14. How does gravity save or kill Q-balls?

    SciTech Connect

    Tamaki, Takashi; Sakai, Nobuyuki

    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 Qballs with arbitrarily small charge, no matter how weak gravity is. That is, gravity saves Q-balls with small charge. We also show how stability of Q-balls changes as gravity becomes strong.

  15. Atmospheric tar balls: aged primary droplets from biomass burning?

    NASA Astrophysics Data System (ADS)

    Tóth, A.; Hoffer, A.; Nyirő-Kósa, I.; Pósfai, M.; Gelencsér, A.

    2013-12-01

    Atmospheric tar balls are particles of special morphology and composition that are abundant in the plumes of biomass smoke. These particles form a specific subset of brown carbon (BrC) which has been shown to play a significant role in atmospheric shortwave absorption and thus climate forcing. Formerly tar balls were hypothesized to be formed in secondary processes in the atmosphere from lignin pyrolysis products. Based on their typical size distributions, morphology, chemical characteristics and other features we now suggest that tar balls are initially produced by the emission of primary tar droplets upon biomass burning. To verify our hypothesis tar balls were produced under laboratory conditions with the total exclusion of flame processes. An all-glass apparatus was designed and tar ball particles were generated from liquid tar obtained previously by dry distillation of wood. The size range, morphology and the chemical composition of the laboratory-generated tar ball particles were similar to those observed in biomass smoke plumes or elsewhere in the atmosphere. Based on our results and the chemical and physical characteristics of tar we suggest that tar balls can be formed by the chemical transformation of emitted primary tar droplets.

  16. Tracking of Ball and Players in Beach Volleyball Videos

    PubMed Central

    Gomez, Gabriel; Herrera López, Patricia; Link, Daniel; Eskofier, Bjoern

    2014-01-01

    This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points. PMID:25426936

  17. Development of the maser-caviton ball lightning theory

    NASA Astrophysics Data System (ADS)

    Handel, Peter H.; Leitner, Jean-Francois

    1994-05-01

    The maser-caviton ball lightning theory is briefly described, is compared with the available observations of ball lightning, and is further developed on the basis of the rate equations governing the evolution of the photon number in a single-mode maser. The focus of this paper is on the explosive growth of the photon number at the premature demise of a large atmospheric maser. Ball lightning is a localized high-field soliton forming a cavity surrounded by plasma in this theory. The source of VHF energy is a large atmospheric maser occupying a volume of serveral cubic miles for the case of open air ball lightning, and occupying the volume of the room in electrically shielded confined ball lightning cases. The main, well-known features of ball lightning, including its appearance right after a strong electric field pulse usually caused by lightning, its passage through closed windows and other dielectrics, its always harmless existence in electrically shielded (e.g., metallic) enclosures, without the possibility of electrostatic-explosive demise, its total absence in the vicinity of high peaks or lightning observation stations, as well as the character of its positioning and motion with respect to conducting bodies, and its apparent lack of buoyancy in the air can all be explained consistently only with the help of this theory as far as we can see. The explosive demise of open air ball lightning is described here in terms of maser spiking phonomena with the help of elementary equations.

  18. Tracking of ball and players in beach volleyball videos.

    PubMed

    Gomez, Gabriel; Herrera López, Patricia; Link, Daniel; Eskofier, Bjoern

    2014-01-01

    This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points. PMID:25426936

  19. Microbial contamination of antiseptic-soaked cotton balls.

    PubMed

    Oie, S; Kamiya, A

    1997-06-01

    We investigated microbial contamination of in-use antiseptics at a hospital. No microbial contamination was observed in 70 samples of 0.02% benzalkonium chloride solution (500-ml volume), 70 samples of 1% titratable I2 povidone-iodine solution (250-ml volume), or 15 samples of 0.1% ethacridine lactate solution (500-ml volume) during use in reduced amounts. Nor was any microbial contamination observed in 70 samples of cotton balls soaked in 1% titratable I2 povidone-iodine solution in canisters or cotton gauze soaked in 70% (w/v) ethanol solution in canisters. However, among 70 samples of cotton balls soaked in 0.02% benzalkonium chloride solution in canisters, 6 (8.6%) were contaminated with 10(4) to 10(6) viable cells/ml. The microbial species detected were glucose non-fermentative bacilli such as Alcaligenes xylosoxidans and Pseudomonas putida. The contaminants obtained from cotton balls soaked in 0.02% benzalkonium chloride solution did not proliferate in that solution or in distilled water but showed rapid growth in the cotton balls soaked in either of these liquids. These findings suggested that benzalkonium chloride solution tends to become contaminated when cotton balls are immersed. Therefore, cotton balls soaked in benzalkonium chloride solution are not recommended as an antiseptic. When no other choice is available, the cotton balls should be soaked in benzalkonium chloride solution at the time of usage. PMID:9212987

  20. Investigation of a Plasma Ball using a High Speed Camera

    NASA Astrophysics Data System (ADS)

    Laird, James; Zweben, Stewart; Raitses, Yevgeny; Zwicker, Andrew; Kaganovich, Igor

    2008-11-01

    The physics of how a plasma ball works is not clearly understood. A plasma ball is a commercial ``toy'' in which a center electrode is charged to a high voltage and lightning-like discharges fill the ball with many plasma filaments. The ball uses high voltage applied on the center electrode (˜5 kV) which is covered with glass and capacitively coupled to the plasma filaments. This voltage oscillates at a frequency of ˜26 kHz. A Nebula plasma ball from Edmund Scientific was filmed with a Phantom v7.3 camera, which can operate at speeds up to 150,000 frames per second (fps) with a limit of >=2 μsec exposure per frame. At 100,000 fps the filaments were only visible for ˜5 μsec every ˜40 μsec. When the plasma ball is first switched on, the filaments formed only after ˜800 μsec and initially had a much larger diameter with more chaotic behavior than when the ball reached its final plasma filament state at ˜30 msec. Measurements are also being made of the final filament diameter, the speed of the filament propagation, and the effect of thermal gradients on the filament density. An attempt will be made to explain these results from plasma theory and movies of these filaments will be shown. Possible theoretical models include streamer-like formation, thermal condensation instability, and dielectric barrier discharge instability.