46 CFR 160.040-6 - Marking and labeling.

Code of Federal Regulations, 2013 CFR

2013-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... rocket-projectiles shall be legibly marked with the name of the manufacturer, the model designation, the...

46 CFR 160.040-6 - Marking and labeling.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... rocket-projectiles shall be legibly marked with the name of the manufacturer, the model designation, the...

46 CFR 160.040-6 - Marking and labeling.

Code of Federal Regulations, 2014 CFR

2014-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... rocket-projectiles shall be legibly marked with the name of the manufacturer, the model designation, the...

46 CFR 160.040-6 - Marking and labeling.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... rocket-projectiles shall be legibly marked with the name of the manufacturer, the model designation, the...

46 CFR 160.040-6 - Marking and labeling.

Code of Federal Regulations, 2010 CFR

2010-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... rocket-projectiles shall be legibly marked with the name of the manufacturer, the model designation, the...

46 CFR 160.040-1 - Incorporation by reference.

Code of Federal Regulations, 2010 CFR

2010-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... incorporated by reference into this subpart: (1) MIL-R-23139 B, 16 August 1965—Rocket Motors, Surface Launched..., Rocket and Projectile Units. (b) The military specifications may be obtained from Customer Service, Naval...

46 CFR 160.040-1 - Incorporation by reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... incorporated by reference into this subpart: (1) MIL-R-23139 B, 16 August 1965—Rocket Motors, Surface Launched..., Rocket and Projectile Units. (b) The military specifications may be obtained from Military Specifications...

46 CFR 160.040-1 - Incorporation by reference.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... incorporated by reference into this subpart: (1) MIL-R-23139 B, 16 August 1965—Rocket Motors, Surface Launched..., Rocket and Projectile Units. (b) The military specifications may be obtained from Customer Service, Naval...

46 CFR 160.040-1 - Incorporation by reference.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... incorporated by reference into this subpart: (1) MIL-R-23139 B, 16 August 1965—Rocket Motors, Surface Launched..., Rocket and Projectile Units. (b) The military specifications may be obtained from Customer Service, Naval...

46 CFR 160.040-1 - Incorporation by reference.

Code of Federal Regulations, 2014 CFR

2014-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Impulse-Projected Rocket Type (and... incorporated by reference into this subpart: (1) MIL-R-23139 B, 16 August 1965—Rocket Motors, Surface Launched..., Rocket and Projectile Units. (b) The military specifications may be obtained from Military Specifications...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 6 2014-10-01 2014-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 6 2010-10-01 2010-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 6 2013-10-01 2013-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 6 2012-10-01 2012-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 6 2011-10-01 2011-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-2 - Type and size.

Code of Federal Regulations, 2010 CFR

2010-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-2 Type and size. (a) The shoulder gun type line-throwing appliance shall be breech-loading for the...

46 CFR 160.031-2 - Type and size.

Code of Federal Regulations, 2014 CFR

2014-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-2 Type and size. (a) The shoulder gun type line-throwing appliance shall be breech-loading for the...

46 CFR 160.031-2 - Type and size.

Code of Federal Regulations, 2013 CFR

2013-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-2 Type and size. (a) The shoulder gun type line-throwing appliance shall be breech-loading for the...

46 CFR 160.031-2 - Type and size.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-2 Type and size. (a) The shoulder gun type line-throwing appliance shall be breech-loading for the...

46 CFR 160.031-2 - Type and size.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-2 Type and size. (a) The shoulder gun type line-throwing appliance shall be breech-loading for the...

46 CFR 160.031-7 - Procedure for approval.

Code of Federal Regulations, 2013 CFR

2013-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-7 Procedure for approval. (a) Shoulder gun line throwing appliances are approved by the Coast...

46 CFR 160.031-7 - Procedure for approval.

Code of Federal Regulations, 2014 CFR

2014-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-7 Procedure for approval. (a) Shoulder gun line throwing appliances are approved by the Coast...

46 CFR 160.031-7 - Procedure for approval.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-7 Procedure for approval. (a) Shoulder gun line throwing appliances are approved by the Coast...

46 CFR 160.031-7 - Procedure for approval.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-7 Procedure for approval. (a) Shoulder gun line throwing appliances are approved by the Coast...

46 CFR 160.031-7 - Procedure for approval.

Code of Federal Regulations, 2010 CFR

2010-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-7 Procedure for approval. (a) Shoulder gun line throwing appliances are approved by the Coast...

Probing the magnetsophere with artificial electron beams

NASA Technical Reports Server (NTRS)

Winckler, J. R.

1981-01-01

An analysis is conducted of the University of Minnesota Electron Echo experiments, which so far have included five sounding rocket experiments. The concept of the Echo experiment is to inject electron beam pulses from a rocket into the ionosphere at altitudes in the range from 100 to 300 km. The electrons move to the conjugate hemisphere following magnetic field lines and return on neighboring field lines to the neighborhood of the rocket where the pulses may be detected and analyzed. Attention is given to the detection and analysis of echoes, the structure of echoes, and the Echo V experiment. The Echo V experiment showed clearly that detection of remote echo beams by atmospheric fluorescence using low light level TV system is not a viable technique. A future experiment is to use throw-away detectors for direct remote echo detection.

In vitro evaluation of square and surgeon's knots in large gauge suture.

PubMed

Gillen, Alex M; Munsterman, Amelia S; Farag, Ramsis; Coleridge, Matthew O D; Hanson, R Reid

2017-02-01

To investigate the strength and size of surgeon's and square knots for starting and ending continuous suture lines using large gauge suture. In vitro mechanical study. Knotted suture. Surgeon's and square knots were tested using 2 and 3 USP polyglactin 910 and 2 USP polydioxanone under linear tension on a universal testing machine. Failure mode and knot holding capacity (KHC) were recorded, and relative knot security (RKS) was calculated as a percentage of KHC. Comparisons were made between number of throws, suture size, suture type, and knot types. Knot volume and weight were assessed by a digital micrometer and balance, respectively. There were no significant differences in KHC (P = .295), RKS (P = .307), volume (P = .128), or weight (P = .310) between square and surgeon's knots at the start or end of suture lines with the same number of throws and suture type. A minimum of 6 throws were required for start knots and 7 throws at end knots to prevent unraveling. Knots tied with 3 polyglactin 910 were strongest (P < .001) and 2 polyglactin 910 produced knots with higher KHC and RKS than 2 polydioxanone (P < .001). No consistent differences were detected between knots types tied with the same suture material; however, number of throws affected KHC and RKS up to 6 throws in start or 7 throws in end knots. The configuration of square and surgeon's knots performed at the end of a continuous line alters their KHC, supporting the use of additional throws for knot security. © 2017 The American College of Veterinary Surgeons.

KSC-2011-1813

NASA Image and Video Library

2011-02-25

CAPE CANAVERAL, Fla. -- A crew member from Freedom Star, one of NASA's solid rocket booster retrieval ships, throws a tow line into the Atlantic Ocean in order to capture the left spent booster nose cap after space shuttle Discovery's STS-133 launch. The shuttle’s two solid rocket booster casings and associated flight hardware are recovered in the Atlantic Ocean after every launch by Liberty Star and Freedom Star. The boosters impact the Atlantic about seven minutes after liftoff and the retrieval ships are stationed about 10 miles from the impact area at the time of splashdown. After the spent segments are processed, they will be transported to Utah, where they will be refurbished and stored, if needed. Photo credit: NASA/Ben Smegelsky

46 CFR 108.597 - Line-throwing appliance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Line-throwing appliance. 108.597 Section 108.597... AND EQUIPMENT Lifesaving Equipment § 108.597 Line-throwing appliance. (a) General. Each unit in international service must have a line-throwing appliance that is approved under approval series 160.040. Each...

33 CFR 87.1 - Need of assistance.

Code of Federal Regulations, 2010 CFR

2010-07-01

...; (c) Rockets or shells, throwing red stars fired one at a time at short intervals; (d) A signal made... burning tar barrel, oil barrel, etc.); (i) A rocket parachute flare or a hand flare showing a red light...

33 CFR 87.1 - Need of assistance.

Code of Federal Regulations, 2011 CFR

2011-07-01

...; (c) Rockets or shells, throwing red stars fired one at a time at short intervals; (d) A signal made... burning tar barrel, oil barrel, etc.); (i) A rocket parachute flare or a hand flare showing a red light...

33 CFR 87.1 - Need of assistance.

Code of Federal Regulations, 2014 CFR

2014-07-01

...; (c) Rockets or shells, throwing red stars fired one at a time at short intervals; (d) A signal made... burning tar barrel, oil barrel, etc.); (i) A rocket parachute flare or a hand flare showing a red light...

33 CFR 87.1 - Need of assistance.

Code of Federal Regulations, 2013 CFR

2013-07-01

...; (c) Rockets or shells, throwing red stars fired one at a time at short intervals; (d) A signal made... burning tar barrel, oil barrel, etc.); (i) A rocket parachute flare or a hand flare showing a red light...

33 CFR 87.1 - Need of assistance.

Code of Federal Regulations, 2012 CFR

2012-07-01

...; (c) Rockets or shells, throwing red stars fired one at a time at short intervals; (d) A signal made... burning tar barrel, oil barrel, etc.); (i) A rocket parachute flare or a hand flare showing a red light...

46 CFR 133.170 - Line-throwing appliance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Line-throwing appliance. 133.170 Section 133.170... SYSTEMS Requirements for All OSVs § 133.170 Line-throwing appliance. (a) General. Each OSV must have a line-throwing appliance that is approved under approval series 160.031 or 160.040. (b) Stowage. The...

Robinson-Trautman solutions to Einstein's equations

NASA Astrophysics Data System (ADS)

Davidson, William

2017-02-01

Solutions to Einstein's equations in the form of a Robinson-Trautman metric are presented. In particular, we derive a pure radiation solution which is non-stationary and involves a mass m, The resulting spacetime is of Petrov Type II A special selection of parametric values throws up the feature of the particle `rocket', a Type D metric. A suitable transformation of the complex coordinates allows the metrics to be expressed in real form. A modification, by setting m to zero, of the Type II metric thereby converting it to Type III, is then shown to admit a null Einstein-Maxwell electromagnetic field.

Kinematic Analysis of Line-Out Throwing in Elite International Rugby Union

PubMed Central

Sayers, Mark G.L.

2011-01-01

The rugby union line-out is a key aspect of game play and involves players from both teams contesting for the ball after it has been thrown in from the side line. Successful lines-out throws require the ball to be delivered accurately to the hands of a jumping and/or lifted team mate (approximately 3-3.5 m off the ground) over distances of between 5- 18 m. Previous research has suggested considerable inter and intra-individual differences in the throwing techniques of international level players. Accordingly, this project investigated the interrelationships between accuracy and the line-out throwing characteristics of three elite international rugby players, and then analyzed whether these changed for throws over increasing length. Three-dimensional (3D) data were developed from video footage (50 Hz) of three elite international subjects for 30 throws over three distances (6 m, 10 m, and 15 m). Results showed notable differences between subjects in many variables at each of the key throw phases. However, several variables such as the degree of trunk flexion at the end of the backswing and at ball release, coupled with elbow flexion angle at ball release remained constant as throw length increased. All subjects exhibited high levels of consistency in movement patterns across all throw lengths. Findings indicated that these high performance line-out throwers shared several common characteristics that will provide useful guides in the development of training programs. Key points A key aspect of this research was the assessment of throwing accuracy using a functional throwing task that mimicked normal performance. Although individual differences in throwing technique occurred, several technical aspects of the throw were common to each of these elite international players. Subjects tended to be extremely consistent in the way they positioned the ball at the end of the backswing, and had very consistent elbow (flexion) and shoulder (flexion and abduction) angles at both the end of the backswing and at ball release. In addition, throwers kept the trunk close to upright during the throw with minimal trunk flexion or extension regardless of throw distance. To throw for longer distances participants tended to increase the involvement of the legs. PMID:24150632

46 CFR 199.170 - Line-throwing appliance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Line-throwing appliance. 199.170 Section 199.170 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LIFESAVING APPLIANCES AND ARRANGEMENTS... appliance. (a) General. Each vessel must have a line-throwing appliance approved under approval series 160...

46 CFR 133.170 - Line-throwing appliance.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Line-throwing appliance. 133.170 Section 133.170 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS LIFESAVING SYSTEMS Requirements for All OSVs § 133.170 Line-throwing appliance. (a) General. Each OSV must have a...

46 CFR 133.170 - Line-throwing appliance.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Line-throwing appliance. 133.170 Section 133.170 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS LIFESAVING SYSTEMS Requirements for All OSVs § 133.170 Line-throwing appliance. (a) General. Each OSV must have a...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2010 CFR

2010-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2013 CFR

2013-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2014 CFR

2014-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

The electron Echo 6 mechanical deployment systems

NASA Technical Reports Server (NTRS)

Meyers, S. C.; Steffen, J. E.; Malcolm, P. R.; Winckler, J. R.

1984-01-01

The Echo 6 sounding rocket payload was flown on a Terrier boosted Black Brant vehicle on March 30, 1983. The experiment requirements resulted in the new design of a rocket propelled Throw Away Detector System (TADS) with onboard Doppler radar, a free-flyer forward experiment designated the Plasma Diagnostic Package (PDP), and numerous other basic systems. The design, developmental testing, and flight preparations of the payload and the mechanical deployment systems are described.

Rocket Science: The Shuttle's Main Engines, though Old, Are not Forgotten in the New Exploration Initiative

NASA Technical Reports Server (NTRS)

Covault, Craig

2005-01-01

The Space Shuttle Main Engine (SSME), developed 30 years ago, remains a strong candidate for use in the new Exploration Initiative as part of a shuttle-derived heavy-lift expendable booster. This is because the Boeing-Rocket- dyne man-rated SSME remains the most highly efficient liquid rocket engine ever developed. There are only enough parts for 12-15 existing SSMEs, however, so one NASA option is to reinitiate SSME production to use it as a throw-away, as opposed to a reusable, powerplant for NASA s new heavy-lift booster.

Defining the Long-Toss: A Professional Baseball Epidemiological Study

PubMed Central

Stone, Austin V.; Mannava, Sandeep; Patel, Anita; Marquez-Lara, Alejandro; Freehill, Michael T.

2017-01-01

Background: Despite widespread use of long-toss throwing in baseball as a component of arm conditioning, interval throwing programs, and rehabilitation, long-toss distance and throwing mechanics remain controversial. Purpose: To ascertain the perceived definition of long-toss throwing through a survey of professional pitchers, pitching coaches (PCs), and certified athletic trainers (ATCs) associated with Major League Baseball. Study Design: Descriptive epidemiology study. Methods: Pitchers, PCs, and ATCs associated with 5 Major League Baseball organizations completed an anonymous survey that collected demographic data, personal use of long-toss throwing, and their perception of the distance and throwing mechanics that comprised long-toss. Results: A total of 321 surveys were completed by 271 pitchers, 19 PCs, and 31 ATCs. For all respondents, the mean distance considered as long-toss was 175 ft (95% CI, 170-181 ft). Respondents categorized the throwing mechanics of long-toss, with 36% reporting throwing “on a line” and 70% reporting long-toss as “not on a line.” Of those throwing “on a line,” 28% reported using crow-hop footwork while 60% used crow-hop footwork when throwing “not on a line.” Interpretation of long-toss distance significantly varied by position: pitchers, 177 ft (95% CI, 171-183 ft); PCs, 177 ft (95% CI, 155-200 ft); and ATCs, 157 ft (95% CI, 144-169 ft) (P = .048). When asked when long-toss throwing is used, pitchers reported using it more frequently in preseason (P = .007), during the season (P = .015), and in the off-season (P = .002) compared with that by ATCs. Functional goals for long-toss throwing demonstrated that pitchers and PCs use long-toss for shoulder stretching more frequently than ATCs (P < .001 and P = .026, respectively). ATCs used long-toss more than pitchers for interval throwing programs (P < .001). Conclusion: The definition varies for long-toss throwing distance and throwing mechanics. Pitchers and PCs believe that long-toss comprised longer distances than ATCs and employed long-toss differently for strength conditioning, training, stretching, and rehabilitation. This discrepancy highlights a potential lost opportunity for protecting the shoulder. While long-toss is an important tool, a more scientific definition is warranted to better elucidate its role in enhancing throwing performance and rehabilitation. PMID:28255565

LETTER TO THE EDITOR: James Bond escapes from slippery ice - how?

NASA Astrophysics Data System (ADS)

2000-07-01

Students respond well to the situation where you tell them that James Bond is lowered onto ice with his girlfriend and left there to freeze to death, slowly. I asked, `What do you do if you are he? Quickly, think, you are freezing. Do something.' They quickly say that they should push off of each other and coast to the bank in opposite directions. Then I ask, `What does James do if he is placed there alone?' Silence follows. I plead with them to think of something, he is dying. But they cannot usually think of anything. Someone finally says he can throw his coat along the surface and coast in the other direction. `Good - so, what is a better thing to throw?' I ask. His shoes, they finally realize. Alright then, is it better to throw one then the other or both at the same time? Now the arguments get excited. Some say throw both, some say one at a time, and some say it does not make any difference. Who is right? I struggled with the problem some years ago when a student asked if it made any difference. The answer is complicated. I published my best effort then in Physics Education (Edmonds 1990). Since then, I have used this problem repeatedly and come to understand it better. The best answer is to throw both at once. You cannot beat that, and it is easiest to do. Besides, it prevents your going into a spin if you throw one carelessly. If you insist on throwing one at a time, then you can produce the same recoil speed if you throw the first shoe with less effort output than would have been given to that shoe if both were thrown together. You make up for this by giving the second shoe more `effort' than it would have gotten when both were thrown. If you do it just right, the two shoes will be moving, one behind the other, with the same speed as they would have had if thrown together, when measured by an outside inertial frame. Since the momentum of the shoes is the same in this frame, then the recoil speed of Bond must be the same as in the first case, in this ice frame, where both were thrown together. Why do you have to throw the second shoe with extra effort? It is going the wrong way when you start to throw it, because the other shoe left Bond going in the opposite direction already. Thus, you throw the first shoe with less than maximum effort and use the leftover energy (somehow?)Â to throw the second shoe extra hard, so they both come out going at the same speed after both have been thrown. If you cannot transfer power from one shoe-throwing arm muscle group to the other arm, then you will use only equal exertion on both shoes, and the second shoe will come out going slower than the first. It was going the wrong way, remember, when you started to throw it, after a delay - any delay. This difference could have been substantial if Bond were throwing bowling balls. A heavy (second) ball will be going the wrong direction with more momentum before you try to start throwing it in the other direction, the direction that the first (heavy) ball was thrown in. It is a cute problem. Suppose that you have hundreds of shoes in a rocket, or in Santa's sleigh, and can only throw one at a time, for some reason, using a machine that you charge with energy to fire it. Best rocket recoil speed will occur when you throw the first shoe out with low speed and increase the charge of the gun with each subsequent shoe shot, such that all the shoes come out moving at the same speed when you are done, as seen in an inertial frame outside the ship. If the shoes have different final energies in this frame, I think the recoil speed of the ship will not be as large. These subtle differences must come from momentum being linearly related to the speed and energy being related to speed squared. Can you prove me wrong? Can you see a simple reason why this must be correct, if it is? This would also apply to ion beam rockets. They can control the acceleration voltage for the beam of ions that they throw out the back. These engines run for a long time, perhaps years. Getting maximum efficiency would be a good idea here. Reference Edmonds J D Jr 1990 Phys. Educ. 25 304-5 James D Edmonds Jr Department of Physics, McNeese State University, Lake Charles, LAÂ 70609, USA

A stone's throw into the universe: A memoir

NASA Technical Reports Server (NTRS)

Zwicky, F.

1977-01-01

Early goals in experimental astronomy are recalled. Physio-chemical properties of the atmosphere were studied by observing the tracks and point-to-point spectra of fast particles from artificial meteors. Some of these self-luminous pellets were fired from an Aerobee rocket in 1958.

46 CFR 160.031-1 - Incorporation by reference.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 6 2012-10-01 2012-10-01 false Incorporation by reference. 160.031-1 Section 160.031-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160...

46 CFR 160.031-1 - Incorporation by reference.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 6 2010-10-01 2010-10-01 false Incorporation by reference. 160.031-1 Section 160.031-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160...

46 CFR 160.031-1 - Incorporation by reference.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 6 2014-10-01 2014-10-01 false Incorporation by reference. 160.031-1 Section 160.031-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160...

46 CFR 160.031-1 - Incorporation by reference.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 6 2011-10-01 2011-10-01 false Incorporation by reference. 160.031-1 Section 160.031-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160...

46 CFR 160.031-1 - Incorporation by reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 6 2013-10-01 2013-10-01 false Incorporation by reference. 160.031-1 Section 160.031-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160...

Association of eye color and sex with basketball free throws by elementary school children.

PubMed

Patee, T; Frewen, M; Beer, J

1991-12-01

Dark-eyed individuals perform reactive activities better while light-eyed individuals generally perform self-paced activities better. There were 68 (21 dark- and 47 light-eyed) elementary school children who shot 5 practice and then 15 free throws from the free-throw line in a high school gym. There were no differences in performance between light- and dark-eyed children, but boys scored more free throws than girls.

46 CFR 160.031-5 - Approval and production tests.

Code of Federal Regulations, 2011 CFR

2011-10-01

... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and... test. The operational test must be conducted as follows: (1) Three rounds must be fired by the gun, at... of the projectile must be in accordance with § 160.031-3(d) the gun must fire each round properly and...

46 CFR 160.031-5 - Approval and production tests.

Code of Federal Regulations, 2014 CFR

2014-10-01

... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and... test. The operational test must be conducted as follows: (1) Three rounds must be fired by the gun, at... of the projectile must be in accordance with § 160.031-3(d) the gun must fire each round properly and...

46 CFR 160.031-5 - Approval and production tests.

Code of Federal Regulations, 2013 CFR

2013-10-01

... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and... test. The operational test must be conducted as follows: (1) Three rounds must be fired by the gun, at... of the projectile must be in accordance with § 160.031-3(d) the gun must fire each round properly and...

46 CFR 160.031-5 - Approval and production tests.

Code of Federal Regulations, 2010 CFR

2010-10-01

... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and... test. The operational test must be conducted as follows: (1) Three rounds must be fired by the gun, at... of the projectile must be in accordance with § 160.031-3(d) the gun must fire each round properly and...

46 CFR 160.031-5 - Approval and production tests.

Code of Federal Regulations, 2012 CFR

2012-10-01

... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and... test. The operational test must be conducted as follows: (1) Three rounds must be fired by the gun, at... of the projectile must be in accordance with § 160.031-3(d) the gun must fire each round properly and...

Release parameters at the foul line and the official result in javelin throwing.

PubMed

Viitasalo, Jukka; Mononen, Harri; Norvapalo, Kare

2003-01-01

Range in javelin throwing is determined by the release parameters and aerodynamic factors. The current study was designed to investigate the effects of release speed, release angle and uncorrected angle of attack measured at the foul line on the official javelin throwing result. The data were collected in international competitions for 26 elite male and 15 elite female javelin throwers (total 248 throws). Multiple regression models were constructed to predict the range of throw for a) individual throwers, b) a group of throwers using the mean value for each thrower in the analysis, and c) all individual throws registered for each gender separately. The data collection was carried out using a computerised photocell gate that consists of two invisible infrared walls two metres apart, perpendicular to the throwing direction. Release speed was found to have the highest correlation with the official throwing result. The three release parameters accounted for 56% of the variance in the official result for the male and 51% for the female throwers. For individual male and female throwers, the variance explained by the model was between 46 and 87%. Among the individual male throwers an increase of 1 m.s-1 in the release speed from 29 to 30 m.s-1 was calculated to increase the official result between 2.12 to 6.14 m while among the female throwers the effect of increase from 24 to 25 m.s-1 in the release speed was from 2.25 to 3.68 m. The study emphasises the importance of investigating javelin throwing biomechanics on an individual thrower basis.

The influence of visual contextual information on the emergence of the especial skill in basketball.

PubMed

Stöckel, Tino; Breslin, Gavin

2013-10-01

We examined whether basketball throwing performance in general and motor skill specificity from the free throw distance in particular are influenced by visual contextual information. Experienced basketball players (N = 36) performed basketball set shots at five distances from the basket. Of particular interest was the performance from the free throw distance (4.23 m), at which experienced basketball players are expected to show superior performance compared with nearby locations as a result of massive amounts of practice. Whereas a control group performed the shots on a regular basketball court, the distance between the rim and the free throw line was either increased or decreased by 30 cm in two experimental groups. Findings showed that only the control group had a superior performance from the free throw distance, and the experimental groups did not. Moreover, all groups performed more accurately from the perceived free throw line (independent of its location) compared with nearby locations. The findings suggest that visual context information influences the presence of specificity effects in experienced performers. The findings have theoretical implications for explaining the memory representation underlying the especial skill effect in basketball.

Comparison of volume, security, and biomechanical strength of square and Aberdeen termination knots tied with 4-0 polyglyconate and used for termination of intradermal closures in canine cadavers.

PubMed

Regier, Penny J; Smeak, Daniel D; Coleman, Kristin; McGilvray, Kirk C

2015-08-01

To compare volumes of square knots and Aberdeen knots in vitro and evaluate security of these knot types when used as buried terminal knots for continuous intradermal wound closures in canine cadavers. Experimental study. 24 surgically closed, full-thickness, 4-cm, epidermal wounds in 4 canine cadavers and 80 knots tied in vitro. Continuous intradermal closures were performed with 4-0 polyglyconate and completed with a buried knot technique. Surgeon (intern or experienced surgeon) and termination knot type (4-throw square knot or 2 + 1 Aberdeen knot; 12 each) were randomly assigned. Closed wounds were excised, and a servohydraulic machine applied tensile load perpendicular to the long axis of the suture line. A load-displacement curve was generated for each sample; maximum load, displacement, stiffness, and mode of construct failure were recorded. Volumes of 2 + 1 Aberdeen (n = 40) and 4-throw square knots (40) tied on a suture board were measured on the basis of a cylindrical model. Aberdeen knots had a mean smaller volume (0.00045 mm(3)) than did square knots (0.003838 mm(3)). Maximum load and displacement did not differ between construct types. Mean stiffness of Aberdeen knot constructs was greater than that of square knots. The 2 + 1 Aberdeen knot had a smaller volume than the 4-throw square knot and was as secure. Although both knots may be reliably used in a clinical setting as the termination knot at the end of a continuous intradermal line, the authors advocate use of the Aberdeen terminal knot on the basis of ease of burying the smaller knot.

Letters

NASA Astrophysics Data System (ADS)

2001-03-01

The Editor welcomes letters, by e-mail to ped@iop.org or by post to Dirac House, Temple Back, Bristol BS1 6BE Contents: Force on a pendulum Sound slows down Bond is back Force on a pendulum The simple pendulum has been used by several educationalists for investigating the patterns of thinking among students and their observations that Aristotelian thinking persists among students at college level. I had also considered the simple pendulum in my 1985 letter in Physics Today [1], so I was interested to read the test given by Lenka Czudková and Jana Musilová [2]. When students were asked to draw net forces acting on the particle at various positions, 31.9% of students believed that the net force was tangential to the particle's path the whole time. To me this is no surprise because in our derivation of the equation for the period of a simple pendulum we assume that the unbalanced sine component provides the restoring force for the harmonic motion of the bob. Of course, Czudková and Musilová's question asked students for the net force on the particle, not the component. The student's answer fits well with the logic of the equilibrium of forces and the parallelogram law. Lastly, let me bring out the similarity between the student's answer and the thinking of George Gamow. He used to call positrons 'donkey' electrons because of their displacement against the applied force, before Paul Dirac termed them positrons. Victor Weisskeptf told me this anecdote in a letter in May 1982. References [1] Sathe D 1985 Phys. Today 38 144 [2] Czudková L and Musilová J 2000 Phys. Educ. 35 428 Dileep V Sathe Dadawala Jr College, Pune, India Sound slows down Without wanting to stir up more trouble amongst the already muddy waters of Physics teaching, consider how many times you have heard (or, more worryingly, read) this: 'Sound waves travel faster in a denser material' But...The velocity of simple longitudinal waves in a bulk medium is given by v = (K/ρ)1/2 where K is the bulk modulus and ρ is the density. Note that the speed is inversely proportional to the square root of the density. The higher the density the lower the speed. A little reasoning will lead to the obvious fact that if a material is more dense, then the mass per unit volume is obviously greater, which implies that the acceleration of any part of the material under application of a force will be less than in a lower density material. In addition, the force producing this acceleration will be due to the stiffness quality of the material. The greater the stiffness the larger the force. How the gross error stated above has found its way into elementary physics texts is beyond me. Perhaps it may have something to do with the Earth and atmosphere modules that seem to be 'hot' topics at the moment, rather than a simple application of Newton II. What amazes me is that if one takes lead and aluminium (not the most uncommon of materials), we find that vAl approx 5000 m s-1 and vlead approx 2000 m s-1. Yet lead is about four times as dense as aluminium! (Who is vetting these books, or is the National Curriculum ignorant of the real world?) Whilst on this subject it seems apparently obvious that a liquid cannot withstand a shear force (it collapses), which is why transverse waves do not travel through the liquid core. Is this simple explanation mentioned? However, in the solid region v = (G/ρ)1/2 where G is the shear modulus - which accounts for the velocity difference compared with compression waves. John Severn George Abbot School, Surrey, UK Bond is back Further to recent correspondence, it is always better for Bond to throw away both of his shoes at once. This will give him maximum velocity on the frictionless ice. Throwing the shoes separately will never match it. This assumes that each shoe is thrown with identical, maximum, effort in either situation. Edmonds [1] is correct to surmise, 'These subtle differences must come from momentum being linearly related to the speed and energy being related to the speed squared.' Oliver Linton [2] 'proved' the opposite. Starting with the maximum effort per throw condition, he wrongly states: 'What this means in practice is that every time Bond throws away a shoe, the separation velocity of the man and shoe is constant, vsep.' This is not correct! The mass of one object (Bond) is less for the second throw. If energy and momentum are conserved then vsep will be greater for the second throw. Consider a general throw (let M and m be the masses of Bond and projectile respectively, V and v their recoil velocities and E the energy transferred from Bond's muscles ('work done') in a single throw): General case Momentum: MV = mv, hence: v2 = (MV/m)2 Energy: E = ½MV2 + ½mv2 2E = MV2 + m(MV/m)2 where R = M/m, and by symmetry. Vsep = V + v (in magnitude) Now consider two cases: Case 1: Very massive Bond: M >> m R is very large so [the first term for vsep] approx 0. In the second term: 1+1/R approx 1. This gives: vsep approx v approx (2E/m)1/2 Case 2: Very low mass Bond: M = m R = 1, both terms are identical and vsep = 2(E/m)1/2 Note: vsep is a factor of surd2 larger for the low mass Bond. In general vsep is not constant if the M:m ratio can change. I concentrated on Bond's final velocity and derived an expression for VS/VB (B = 'both together', S = 'separate throws'). (For a fuller account of the algebra e-mail me!) Case 'B' The same as the 'General case', but replace E by 2E (uses two arms), m by 2m and V by VB: Case 'S' 1st throw: U = velocity of Bond and remaining shoe in the 'Ice Frame' after throw. (As for Case 'B' but replacing M by (M + m), 2m by m and 2E by just E.) 2nd throw: Start by finding VCM (recoil velocity of Bond) in the centre of mass (CM) frame (which has a velocity, U, in the 'Ice Frame'). (Again use Case 'B' by just replacing 2E by E and 2m by m.) VS = VCM + U (transforming from CM to Ice Frame) Final result (after 'a bit' of algebra!) VS/VB = (1/surd2) (1+R/2)1/2 ? [(1+R)-1/2 + (3+2/R+R)-1/2] This result is not very illuminating unless we try a few examples: (a) M = m (heavy shoes!) so R = 1: ∴ VS/VB = 0.966. (b) M = 75 kg and m = 0.5 kg (sensible values), so R =150: VS/VB = 0.999994517. Conclusions Edmonds is correct. He rightly concluded that the only way to match the recoil velocity of the pair of shoes is to arrange for the shoe velocities in the separate throws to be the same (in the Ice Frame) as the pair of shoes. This is why he invoked the 'extra effort' idea that Oliver Linton and I dismissed. However, he points out that if this is not available then Bond's velocity will be less if he throws separately. Application to rocket propulsion Some of Oliver Linton's statements about the 'well known' formula for rocket propulsion are also incorrect. The separation speed of fuel and rocket, vs, is assumed to be constant in the equation - which for a normal rocket is a very good approximation because at any instant the mass of ejected fuel is always much smaller than the mass of rocket and remaining fuel (if any). This is analogous to my 'Case 1' where vs = vsep approx (2E/m)1/2 and m << M. Oliver Linton's example of ejecting all the fuel at once from a rocket in which m = M is just my 'Case 2'. The separation velocity here is vall. It was noted after 'Case 2' that vall = surd2 vsep The rocket formula (gradual release of fuel) V = vsln[(M + m)/M] gives V = ln2 vs = 0.693 vsep (using the vs from Case 1). But when all the mass is ejected at once we now have (besides a 'bomb'!): V = ½ vall = ½ (surd2 vsep) = 0.707 vsep and not the 0.5 vsep (or '50%') quoted by Oliver Linton. The reasons why rockets are designed to operate to give this lower theoretical maximum speed are numerous but mainly revolve around not killing the astronauts, not destroying the rocket or reducing drag at lift-off. References [1] Edmonds J D 2000 Phys. Educ. 35 225 [2] Linton J O 2000 Phys. Educ. 35 317-8 Laurence Caves Blessed George Napier RC School Addison Road, Banbury OX16 9DG, UK LCaves@blessed-george-napier.oxon.sch.uk

Fin-line PIN-diode attenuators and switches for 94 GHz range

NASA Astrophysics Data System (ADS)

Meinel, H.; Callsen, H.

1982-06-01

The letter reports new results of fin-line PIN-diode attenuators and switches for the 94 GHz range. Design and performance of SPST and SPDT switches - single pole single throw and single pole double throw, respectively - will be presented. The attenuation of the SPST switch, for example, can be adjusted between 2 and 35 dB over the entire waveguide band from 75 to 110 GHz.

Preliminary results of rocket attitude and auroral green line emission rate in the DELTA campaign

NASA Astrophysics Data System (ADS)

Iwagami, Naomoto; Komada, Sayaka; Takahashi, Takao

2006-09-01

The attitude of a sounding rocket launched in the DELTA (Dynamics and Energetics of the Lower Thermosphere in Aurora) campaign was determined with IR horizon sensors and geomagnetic sensors. Since the payload was separated into two portions, two sets of attitude sensors were needed. A new IR sensor was developed for the present experiment, and found the zenith-angle of the spin-axis of the rocket with an accuracy of 2°. By combining information obtained by both type of sensors, the absolute attitudes were determined. The auroral green line emission rate was measured by a photometer on board the same rocket launched under active auroral conditions, and the energy flux of the auroral particle precipitation was estimated.

Self-Paced and Temporally Constrained Throwing Performance by Team-Handball Experts and Novices without Foreknowledge of Target Position

PubMed Central

Rousanoglou, Elissavet N.; Noutsos, Konstantinos S.; Bayios, Ioannis A.; Boudolos, Konstantinos D.

2015-01-01

The fixed duration of a team-handball game and its continuously changing situations incorporate an inherent temporal pressure. Also, the target’s position is not foreknown but online determined by the player’s interceptive processing of visual information. These ecological limitations do not favour throwing performance, particularly in novice players, and are not reflected in previous experimental settings of self-paced throws with foreknowledge of target position. The study investigated the self-paced and temporally constrained throwing performance without foreknowledge of target position, in team-handball experts and novices in three shot types (Standing Shot, 3Step Shot, Jump Shot). The target position was randomly illuminated on a tabloid surface before (self-paced condition) and after (temporally constrained condition) shot initiation. Response time, throwing velocity and throwing accuracy were measured. A mixed 2 (experience) X 2 (temporal constraint condition) ANOVA was applied. The novices performed with significantly lower throwing velocity and worse throwing accuracy in all shot types (p = 0.000) and, longer response time only in the 3Step Shot (p = 0.013). The temporal constraint (significantly shorter response times in all shot types at p = 0.000) had a shot specific effect with lower throwing velocity only in the 3Step Shot (p = 0.001) and an unexpected greater throwing accuracy only in the Standing Shot (p = 0.002). The significant interaction between experience and temporal constraint condition in throwing accuracy (p = 0.003) revealed a significant temporal constraint effect in the novices (p = 0.002) but not in the experts (p = 0.798). The main findings of the study are the shot specificity of the temporal constraint effect, as well as that, depending on the shot, the novices’ throwing accuracy may benefit rather than worsen under temporal pressure. Key points The temporal constraint induced a shot specific significant difference in throwing velocity in both the experts and the novices. The temporal constraint induced a shot specific significant difference in throwing accuracy only in the novices. Depending on the shot demands, the throwing accuracy of the novices may benefit under temporally constrained situations. PMID:25729288

Relationship of pectoralis major muscle size with bench press and bench throw performances.

PubMed

Akagi, Ryota; Tohdoh, Yukihiro; Hirayama, Kuniaki; Kobayashi, Yuji

2014-06-01

This study examined the relationship of muscle size indices of the pectoralis major muscle with bench press and bench throw performances in 18 male collegiate athletes. The maximal cross-sectional area (MCSAMAx) and volume (MV) of the pectoralis major muscle were determined by magnetic resonance imaging. First, subjects were tested for their one repetition maximum bench press strength (1RMBP) using a Smith machine. At a later date, subjects performed bench throws using the Smith machine with several different loads ranging from 30.0 kg to 90% of 1RMBP. Barbell positions were measured by a linear position transducer, and bench throw power was calculated using a dynamic equation. Three trials were performed for each load. In all the trials, the maximal peak power was adopted as bench throw peak power (PPBT). The 1RMBP was significantly correlated with MCSAMAx. Similarly, the correlation coefficient between MV and PPBT was significant. In contrast to the y-intercept of the MV-PPBT regression line, that of the MCSAMAx-1RMBP regression line was not significantly different from 0. These results suggested that, although the dependence on pectoralis major muscle size is slightly different between bench press strength and bench throw power, the pectoralis major muscle size has a significant impact on bench press and throw performances. Greater muscle size leads to heavier body weight, which can be a negative factor in some sports. We therefore recommend that athletes and their coaches develop training programs for improving sports performance by balancing the advantage of increased muscle size and the potential disadvantage of increased body weight.

Relationship among maximal grip, throwing velocity and anthropometric parameters in elite water polo players.

PubMed

Ferragut, C; Vila, H; Abraldes, J A; Argudo, F; Rodriguez, N; Alcaraz, P E

2011-03-01

As independent aspects, body size, body composition, and physiological performance of elite athletes have aroused the interest of sports scientists but, unfortunately, studies that combine these aspects are scarcely avalaible in water polo. The aim of the present study was to: 1) to develop an anthropometric profile of highly skilled male Water Polo players, and 2) to identify significant relationships between these features and overhead throwing velocity in highly skilled male water polo players. Thirteen male water polo players, with a mean age of 26.10±4.82, were recruited from the Spanish Water Polo team and an anthropometric assessment on all of them was carried out. Throwing velocity was evaluated in three different situations from the 5 m-penalty line on the center of the water polo goal: A) throwing without a defender nor a goalkeeper; B) throwing with a goalkeeper only, and C) 3) armfuls running shot with goalkeeper. Maximal handgrip was also tested. Biacromial breadth shows a significative correlation with hand grip in water polo players (r=0.792; P=0.001) and also correlates with Throwing velocity (r=0.716; P<0.001). Biepicondylar femur breadth correlates significatively with hand grip (r=0.727; P<0.05) and also with throwing velocity in "throwing with goalkeeper" situation (r=0.664; P<0.05). Hand grip shows a significant correlation with throwing velocity in "throwing with goalkeeper" situation (r=0.603; P<0.05). In conclusion, body mass aspects are not related with throwing velocity in highly skilled Water Polo players. Maximal hand grip is related with throwing velocity in "throwing with goalkeeper" situation. More investigations about water polo are necessary.

Skill-dependent proximal-to-distal sequence in team-handball throwing.

PubMed

Wagner, Herbert; Pfusterschmied, Jürgen; Von Duvillard, Serge P; Müller, Erich

2012-01-01

The importance of proximal-to-distal sequencing in human performance throwing has been reported previously. However, a comprehensive comparison of the proximal-to-distal sequence in team-handball throwing in athletes with different training experience and competition is lacking. Therefore, the aim of the study was to compare the ball velocity and proximal-to-distal sequence in the team-handball standing throw with run-up of players of different skill (less experienced, experienced, and elite). Twenty-four male team-handball players (n = 8 for each group) performed five standing throws with run-up with maximal ball velocity and accuracy. Kinematics and ball trajectories were recorded with a Vicon motion capture system and joint movements were calculated. A specific proximal-to-distal sequence, where elbow flexion occurred before shoulder internal rotation, was found in all three groups. These results are in line with previous studies in team-handball. Furthermore, the results of the present study suggest that in the team-handball standing throw with run-up, increased playing experience is associated with an increase in ball velocity as well as a delayed start to trunk flexion.

Return to play after nonoperative management for a severe type III acromioclavicular separation in the throwing shoulder of a collegiate pitcher.

PubMed

Watson, Scott T; Wyland, Douglas J

2015-02-01

Treatment of type III acromioclavicular (AC) separations is controversial, especially in the dominant shoulder of a high-level throwing athlete. This case report describes the return to play after nonoperative management of a collegiate baseball pitcher with a severe type III AC separation in his throwing shoulder. Case report of return to play with nonoperative management of a type III AC separation in the throwing shoulder of a collegiate pitcher. A case report of a single patient. Prospective data were recorded in the case of a collegiate pitcher who suffered an acute injury to the dominant shoulder, resulting in a severe type III AC separation. He was initially treated with a figure-of-8 brace and a sling. Postinjury, strengthening of the wrist, hand, and elbow began at 3½ weeks, and shoulder range of motion (ROM) and a periscapular strengthening program began at 6 weeks. At 2 months postinjury, a deformity was still present, but the athlete was pain free, with full shoulder ROM and strength without tenderness at the AC joint. Formal physical therapy was initiated to include an accelerated interval throwing program. At 12 weeks postinjury, the athlete was pitching asymptomatically, and gradually returned to regular play. At 6 months and now through 24 months postinjury, the athlete reported full strength, full ROM, and return to his previous level of throwing and velocity without complication. He volunteered that he was 100% satisfied with the result, and feels he is the same pitcher as, if not stronger than, prior to this injury. This case demonstrates a collegiate baseball pitcher who returned to his preinjury level of pitching with nonoperative treatment of a severe type III AC separation.

Maximal power training induced different improvement in throwing velocity and muscle strength according to playing positions in elite male handball players

PubMed Central

Chtourou, H; Souissi, N; Aouidet, A; Chamari, K

2016-01-01

This study was designed to assess the effect of strength and power training on throwing velocity and muscle strength in handball players according to their playing positions. Twenty-two male handball players were assigned to either an experimental group (n=11) or a control group (n=11) (age: 22.1 ± 3.0 years). They were asked to complete (i) the ball throwing velocity test and (ii) the one-repetition maximum (1-RM) tests for the half-back squat, the pull-over, the bench press, the developed neck, and the print exercises before and after 12 weeks of maximal power training. The training was designed to improve strength and power with an intensity of 85-95% of the 1RM. In addition to their usual routine handball training sessions, participants performed two sessions per week. During each session, they performed 3-5 sets of 3-8 repetitions with 3 min of rest in between. Then, they performed specific shots (i.e., 12 to 40). Ball-throwing velocity (p<0.001) was higher after the training period in rear line players (RL). The training programme resulted in an improvement of 1RM bench press (p<0.001), 1RM developed neck (p<0.001) and 1RM print (p<0.001) in both front line (FL) and RL. The control group showed a significant improvement only in ball-throwing velocity (p<0.01) and 1RM bench press (p<0.01) in RL. A significantly greater improvement was found in ball-throwing velocity (p<0.001), 1RM bench press (p<0.001), and 1RM half-back squat exercises in players of the central axis (CA) compared to the lateral axis (LA) (p<0.01). The power training programme induced significantly greater increases in ball-throwing velocity and muscle strength in FL than RL and in CA than LA axis players. PMID:28090144

Maximal power training induced different improvement in throwing velocity and muscle strength according to playing positions in elite male handball players.

PubMed

Cherif, M; Chtourou, H; Souissi, N; Aouidet, A; Chamari, K

2016-12-01

This study was designed to assess the effect of strength and power training on throwing velocity and muscle strength in handball players according to their playing positions. Twenty-two male handball players were assigned to either an experimental group (n=11) or a control group (n=11) (age: 22.1 ± 3.0 years). They were asked to complete (i) the ball throwing velocity test and (ii) the one-repetition maximum (1-RM) tests for the half-back squat, the pull-over, the bench press, the developed neck, and the print exercises before and after 12 weeks of maximal power training. The training was designed to improve strength and power with an intensity of 85-95% of the 1RM. In addition to their usual routine handball training sessions, participants performed two sessions per week. During each session, they performed 3-5 sets of 3-8 repetitions with 3 min of rest in between. Then, they performed specific shots (i.e., 12 to 40). Ball-throwing velocity (p<0.001) was higher after the training period in rear line players (RL). The training programme resulted in an improvement of 1RM bench press (p<0.001), 1RM developed neck (p<0.001) and 1RM print (p<0.001) in both front line (FL) and RL. The control group showed a significant improvement only in ball-throwing velocity (p<0.01) and 1RM bench press (p<0.01) in RL. A significantly greater improvement was found in ball-throwing velocity (p<0.001), 1RM bench press (p<0.001), and 1RM half-back squat exercises in players of the central axis (CA) compared to the lateral axis (LA) (p<0.01). The power training programme induced significantly greater increases in ball-throwing velocity and muscle strength in FL than RL and in CA than LA axis players.

Kinematic patterns underlying disguised movements: Spatial and temporal dissimilarity compared to genuine movement patterns.

PubMed

Helm, Fabian; Munzert, Jörn; Troje, Nikolaus F

2017-08-01

This study examined the kinematic characteristics of disguised movements by applying linear discriminant (LDA) and dissimilarity analyses to the motion data from 788 disguised and 792 non-disguised 7-m penalty throws performed by novice and expert handball field players. Results of the LDA showed that discrimination between type of throws (disguised vs. non-disguised) was more error-prone when throws were performed by experts (spatial: 4.6%; temporal: 29.6%) compared to novices (spatial: 1.0%; temporal: 20.2%). The dissimilarity analysis revealed significantly smaller spatial dissimilarities and variations between type of throws in experts compared to novices (p<0.001), but also showed that these spatial dissimilarities and variations increased significantly in both groups the closer the throws came to the moment of (predicted) ball release. In contrast, temporal dissimilarities did not differ significantly between groups. Thus, our data clearly demonstrate that expertise in disguising one's own action intentions results in an ability to perform disguised penalty throws that are highly similar to genuine throws. We suggest that this expertise depends mainly on keeping spatial dissimilarities small. However, the attempt to disguise becomes a challenge the closer one gets to the action outcome (i.e., ball release) becoming visible. Copyright © 2017 Elsevier B.V. All rights reserved.

Judgement bias in predicting the success of one's own basketball free throws but not those of others.

PubMed

Cañal-Bruland, Rouwen; Balch, Lars; Niesert, Loet

2015-07-01

Skilled basketball players are supposed to hit more often from the free throw distance than would be predicted by their shooting performances at adjacent distances. This is dubbed an especial skill. In the current study, we examined whether especial skills in free throw performance in basketball map onto especial skills in visually judging the success of basketball free throws. In addition, we tested whether this effect would be present in those who predict their own shots but absent in those who judge shots performed by another person. Eight skilled basketball players were coupled with eight equally skilled players, and performed 150 set shots from five different distances (including the free throw distance) while the yoked partner observed the shots. At the moment of ball release, the performers' and the observers' vision were synchronously occluded using liquid-crystal occlusion goggles, and both independently judged whether the shot was successful or not. Results did not replicate an especial skill effect in shooting performance. Based on signal detection theory (SDT) measures (d' and criterion c), results also revealed no especial skill for visually discriminating successful from unsuccessful shots at the foul line when compared to other distances. However, players showed an especial skill judgement bias towards judging balls 'in' at the foul line, but not at other distances. Importantly, this bias was only present in those who judged the success of their own shots, but not in those who judged the shots performed by someone else.

Effects of Strength vs. Ballistic-Power Training on Throwing Performance

PubMed Central

Zaras, Nikolaos; Spengos, Konstantinos; Methenitis, Spyridon; Papadopoulos, Constantinos; Karampatsos, Giorgos; Georgiadis, Giorgos; Stasinaki, Aggeliki; Manta, Panagiota; Terzis, Gerasimos

2013-01-01

The purpose of the present study was to investigate the effects of 6 weeks strength vs. ballistic-power (Power) training on shot put throwing performance in novice throwers. Seventeen novice male shot-put throwers were divided into Strength (N = 9) and Power (n = 8) groups. The following measurements were performed before and after the training period: shot put throws, jumping performance (CMJ), Wingate anaerobic performance, 1RM strength, ballistic throws and evaluation of architectural and morphological characteristics of vastus lateralis. Throwing performance increased significantly but similarly after Strength and Power training (7.0-13.5% vs. 6.0-11.5%, respectively). Muscular strength in leg press increased more after Strength than after Power training (43% vs. 21%, respectively), while Power training induced an 8.5% increase in CMJ performance and 9.0 - 25.8% in ballistic throws. Peak power during the Wingate test increased similarly after Strength and Power training. Muscle thickness increased only after Strength training (10%, p < 0.05). Muscle fibre Cross Sectional Area (fCSA) increased in all fibre types after Strength training by 19-26% (p < 0.05), while only type IIx fibres hypertrophied significantly after Power training. Type IIx fibres (%) decreased after Strength but not after Power training. These results suggest that shot put throwing performance can be increased similarly after six weeks of either strength or ballistic power training in novice throwers, but with dissimilar muscular adaptations. Key points Ballistic-power training with 30% of 1RM is equally effective in increasing shot put performance as strength training, in novice throwers, during a short training cycle of six weeks. In novice shot putters with relatively low initial muscle strength/mass, short-term strength training might be more important since it can increase both muscle strength and shot put performance. The ballistic type of power training resulted in a significant increase of the mass of type IIx muscle fibres and no change in their proportion. Thus, this type of training might be used effectively during the last weeks before competition, when the strength training load is usually reduced, in order to increase muscle power and shot put performance in novice shot putters. PMID:24149736

Effects of Strength vs. Ballistic-Power Training on Throwing Performance.

PubMed

Zaras, Nikolaos; Spengos, Konstantinos; Methenitis, Spyridon; Papadopoulos, Constantinos; Karampatsos, Giorgos; Georgiadis, Giorgos; Stasinaki, Aggeliki; Manta, Panagiota; Terzis, Gerasimos

2013-01-01

The purpose of the present study was to investigate the effects of 6 weeks strength vs. ballistic-power (Power) training on shot put throwing performance in novice throwers. Seventeen novice male shot-put throwers were divided into Strength (N = 9) and Power (n = 8) groups. The following measurements were performed before and after the training period: shot put throws, jumping performance (CMJ), Wingate anaerobic performance, 1RM strength, ballistic throws and evaluation of architectural and morphological characteristics of vastus lateralis. Throwing performance increased significantly but similarly after Strength and Power training (7.0-13.5% vs. 6.0-11.5%, respectively). Muscular strength in leg press increased more after Strength than after Power training (43% vs. 21%, respectively), while Power training induced an 8.5% increase in CMJ performance and 9.0 - 25.8% in ballistic throws. Peak power during the Wingate test increased similarly after Strength and Power training. Muscle thickness increased only after Strength training (10%, p < 0.05). Muscle fibre Cross Sectional Area (fCSA) increased in all fibre types after Strength training by 19-26% (p < 0.05), while only type IIx fibres hypertrophied significantly after Power training. Type IIx fibres (%) decreased after Strength but not after Power training. These results suggest that shot put throwing performance can be increased similarly after six weeks of either strength or ballistic power training in novice throwers, but with dissimilar muscular adaptations. Key pointsBallistic-power training with 30% of 1RM is equally effective in increasing shot put performance as strength training, in novice throwers, during a short training cycle of six weeks.In novice shot putters with relatively low initial muscle strength/mass, short-term strength training might be more important since it can increase both muscle strength and shot put performance.The ballistic type of power training resulted in a significant increase of the mass of type IIx muscle fibres and no change in their proportion. Thus, this type of training might be used effectively during the last weeks before competition, when the strength training load is usually reduced, in order to increase muscle power and shot put performance in novice shot putters.

Design and Experimental Study on Spinning Solid Rocket Motor

NASA Astrophysics Data System (ADS)

Xue, Heng; Jiang, Chunlan; Wang, Zaicheng

The study on spinning solid rocket motor (SRM) which used as power plant of twice throwing structure of aerial submunition was introduced. This kind of SRM which with the structure of tangential multi-nozzle consists of a combustion chamber, propellant charge, 4 tangential nozzles, ignition device, etc. Grain design, structure design and prediction of interior ballistic performance were described, and problem which need mainly considered in design were analyzed comprehensively. Finally, in order to research working performance of the SRM, measure pressure-time curve and its speed, static test and dynamic test were conducted respectively. And then calculated values and experimental data were compared and analyzed. The results indicate that the designed motor operates normally, and the stable performance of interior ballistic meet demands. And experimental results have the guidance meaning for the pre-research design of SRM.

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

PubMed

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

2018-01-01

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

Prioritization of anticancer drugs against a cancer using genomic features of cancer cells: A step towards personalized medicine

PubMed Central

Gupta, Sudheer; Chaudhary, Kumardeep; Kumar, Rahul; Gautam, Ankur; Nanda, Jagpreet Singh; Dhanda, Sandeep Kumar; Brahmachari, Samir Kumar; Raghava, Gajendra P. S.

2016-01-01

In this study, we investigated drug profile of 24 anticancer drugs tested against a large number of cell lines in order to understand the relation between drug resistance and altered genomic features of a cancer cell line. We detected frequent mutations, high expression and high copy number variations of certain genes in both drug resistant cell lines and sensitive cell lines. It was observed that a few drugs, like Panobinostat, are effective against almost all types of cell lines, whereas certain drugs are effective against only a limited type of cell lines. Tissue-specific preference of drugs was also seen where a drug is more effective against cell lines belonging to a specific tissue. Genomic features based models have been developed for each anticancer drug and achieved average correlation between predicted and actual growth inhibition of cell lines in the range of 0.43 to 0.78. We hope, our study will throw light in the field of personalized medicine, particularly in designing patient-specific anticancer drugs. In order to serve the scientific community, a webserver, CancerDP, has been developed for predicting priority/potency of an anticancer drug against a cancer cell line using its genomic features (http://crdd.osdd.net/raghava/cancerdp/). PMID:27030518

Comparison of range of motion tests with throwing kinematics in elite team handball players.

PubMed

van den Tillaar, Roland

2016-10-01

The aim of this study was to compare the active and passive range of motion (ROM) of the glenohumeral external rotation with the maximal external rotation and throwing performance during different throws with different wind-up techniques in elite team handball players. Twenty-two elite team handball players participated in the study in which the maximal ball release velocity and maximal external rotation during standing, with run-up and jump throws with two types of wind-ups were measured together with the maximal active and passive glenohumeral ROM of the external rotation, lying supine on a bench. Higher maximal external rotation was found during the throws with the whip-like wind-up in comparison to circular-like wind-up throws together with a lower external rotation during the active ROM test. No correlations were found between the ROM of the external rotation with the maximal ball release velocity and the maximal external rotation measured during the throws. It was concluded that ROM of the external rotation measured on the bench does not give any information about the maximal throwing performance or the external rotation angle during throwing and therefore cannot be used to identify potential fast throwers or injuries in elite team handball players.

Comparing performance and kinematics of throwing with a circular and whip-like wind up by experienced handball players.

PubMed

van den Tillaar, R; Zondag, A; Cabri, J

2013-12-01

The aim of this study was to compare the performance (throwing velocity of the ball) and kinematics of overarm throwing with the circular and whip-like wind up in elite handball players. Twenty-two elite handball players (11 men and 11 women) conducted both types of throws. The ball release velocity, maximal ball acceleration, maximal velocity of the end points of the five segments and maximal angles, angles at ball release and maximal angular velocities of the 11 joint movements and their timing during the throw were analyzed. Significantly higher ball release velocities (21.9 m/s vs 20.6 m/s) were reached together with higher maximal linear velocities of the end points of all segments and longer throwing time with the circular wind up than with the whip-like wind up. Furthermore, it seems that the timing and amount of maximal angular pelvis rotation was the main contributor to the difference in the maximal ball release velocity between the two wind ups. The findings support the observation that overarm throwing with the circular wind up results in higher ball releases but also a longer throwing movement in comparison to whip-like wind up throws. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Rocket Spectroheliograph for the Mg II Line at 2802.7 A.

PubMed

Fredga, K

1969-02-01

A rocket-borne spectroheliograph designed to take monochromatic pictures of the sun in the Mg II line at 2802.7 A is described in detail. The photographic system consists of a Questar telescope, a Solc type birefringent filter, and an automatic Robot camera. The double Solc filter has a spectral bandwidth of 3.5 A. The two units in the double filter have been thoroughly tested and are compared with theoretically calculated transmission curves. Two new types of linear film polarizers for the uv region have been tested and used in the filter. A temperature control unit was developed which stabilized the filter temperature in flight to within +/-0.2 degrees C. The instrument has been tested in vacuum and to the Aerobee 150 vibration specifications. It has been flown and successfully recovered three times and performed excellently during each fight.

Burns during Easter festivities in Greece.

PubMed

Pallantzas, A; Kourakos, P; Stampolidis, N; Papagianni, E; Balagoura, A; Stathopoulos, A; Polizoi, A; Emvalomata, A; Evaggelopoulou, M; Castana, O

2012-12-31

Easter is the most important holiday for the Greek Church. It is rich in traditions and rituals but during the Greek Easter festivities, especially at midnight Mass on Easter Saturday night, it is customary to throw fireworks around. These fireworks are not part of the true Easter tradition and they are potentially fatal. Unfortunately, in the past few years, the custom has become more and more popular in Greece. There are some local variations, mainly in the Aegean islands, where homemade rockets are used to have a "rocket war". The rockets consist of wooden sticks loaded with an explosive mixture containing gunpowder and launched from special platforms. Many severe injuries involving loss of sight and limbs as well as major burns are also caused by the use of illegal fireworks at Easter. Every year numerous burn victims are hospitalized. The most affected areas are the face, the upper extremities, and the chest, often in association with slight or severe wounds and injuries. This study presents our department's experience with incidents due to the use of fireworks during Easter festivities.

Field of Vision Influences Sensory-Motor Control of Skilled and Less-Skilled Dart Players

PubMed Central

Rienhoff, Rebecca; Baker, Joseph; Fischer, Lennart; Strauss, Bernd; Schorer, Jörg

2012-01-01

One characteristic of perceptual expertise in sport and other domains is known as ’the quiet eye', which assumes that fixated information is processed during gaze stability and insufficient spatial information leads to a decrease in performance. The aims of this study were a) replicating inter- and intra-group variability and b) investigating the extent to which quiet eye supports information pick-up of varying fields of vision (i.e., central versus peripheral) using a specific eye-tracking paradigm to compare different skill levels in a dart throwing task. Differences between skill levels were replicated at baseline, but no significant differences in throwing performance were revealed among the visual occlusion conditions. Findings are generally in line with the association between quiet eye duration and aiming performance, but raise questions regarding the relevance of central vision information pick-up for the quiet eye. Key pointsInvestigation of throwing performance and quiet eye duration in dart throwing under several vision conditionsFirst investigation using a dynamic occlusion paradigm, manipulating field of vision in situReplication of previous findings concerning throwing performance and quiet eye durationNew insights about the role of central (and peripheral) vision concerning the quiet eye phenomena PMID:24149366

Dizziness in discus throwers is related to motion sickness generated while spinning.

PubMed

Perrin, P; Perrot, C; Deviterne, D; Ragaru, B; Kingma, H

2000-03-01

While both discus and hammer throwing involve rotating movements resulting in the throw of an object, discus throwers sometimes report dizziness, a condition never experienced by hammer throwers. We investigated whether this susceptibility was related to the sensitivity of the thrower or to the type of throwing achieved. For the latter, we compared the determining features of gesture, gaze stabilization and projectile trajectory in both sports. A total of 22 high-level sportsmen in these 2 disciplines, half of them practising both sports, were interviewed. Slow motion video recordings of discus and hammer throwing were examined to determine the visual referential, head movements and plantar surface support area involved at each stage of the motions. Discomfort was reported by 59% of the sportsmen while throwing discus, but by none while throwing hammer. Because several individuals practised both sports, these results exclude the hypothesis of individual susceptibility to dizziness. Video analysis evidenced that during hammer throwing, visual bearings can be used more easily than during discus throwing. Moreover, there is a loss of plantar afferents and generation of head movements liable to induce motion sickness, such as Coriolis acceleration. In conclusion, although hammer and discus-throwing present numerous similarities, we demonstrate here that crucial differences in the specific execution of each sport are responsible for the dizziness experienced by discus throwers.

Stinger Post Hybrid Simulation: Design Description and Users’ Manual

DTIC Science & Technology

1983-04-01

function of three variables. Table 4 MVFG Modes £ ?*" Mode Function Number Argument Number Trunking Station Address Output Hole Argument...between JA and J7. This permits the signal to control a normally-open, single-throw minature relay. It closes the remote operate line when a logic...logic functions are also performed on the card. A normally- open, single-throw minature relay (U5) and an AND gate (1/4 of Ul) are used to perform the

C3 Performance of the Ares-I Launch Vehicle and its Capabilities for Lunar and Interplanetary Science Missions

NASA Technical Reports Server (NTRS)

Thomas, H. Dan

2008-01-01

NASA s Ares-I launch vehicle will be built to deliver the Orion spacecraft to Low-Earth orbit, servicing the International Space Station with crew-transfer and helping humans begin longer voyages in conjunction with the larger Ares-V. While there are no planned missions for Ares-I beyond these, the vehicle itself offers an additional capability for robotic exploration. Here we present an analysis of the capability of the Ares-I rocket for robotic missions to a variety of destinations, including lunar and planetary exploration, should such missions become viable in the future. Preliminary payload capabilities using both single and dual launch architectures are presented. Masses delivered to the lunar surface are computed along with throw capabilities to various Earth departure energies (i.e. C3s). The use of commercially available solid rocket motors as additional payload stages were analyzed and will also be discussed.

Predicting Electron Population Characteristics in 2-D Using Multispectral Ground-Based Imaging

NASA Astrophysics Data System (ADS)

Grubbs, Guy; Michell, Robert; Samara, Marilia; Hampton, Donald; Jahn, Jorg-Micha

2018-01-01

Ground-based imaging and in situ sounding rocket data are compared to electron transport modeling for an active inverted-V type auroral event. The Ground-to-Rocket Electrodynamics-Electrons Correlative Experiment (GREECE) mission successfully launched from Poker Flat, Alaska, on 3 March 2014 at 11:09:50 UT and reached an apogee of approximately 335 km over the aurora. Multiple ground-based electron-multiplying charge-coupled device (EMCCD) imagers were positioned at Venetie, Alaska, and aimed toward magnetic zenith. The imagers observed the intensity of different auroral emission lines (427.8, 557.7, and 844.6 nm) at the magnetic foot point of the rocket payload. Emission line intensity data are correlated with electron characteristics measured by the GREECE onboard electron spectrometer. A modified version of the GLobal airglOW (GLOW) model is used to estimate precipitating electron characteristics based on optical emissions. GLOW predicted the electron population characteristics with 20% error given the observed spectral intensities within 10° of magnetic zenith. Predictions are within 30% of the actual values within 20° of magnetic zenith for inverted-V-type aurora. Therefore, it is argued that this technique can be used, at least in certain types of aurora, such as the inverted-V type presented here, to derive 2-D maps of electron characteristics. These can then be used to further derive 2-D maps of ionospheric parameters as a function of time, based solely on multispectral optical imaging data.

Measurements of temperature profiles at the exit of small rockets.

PubMed

Griggs, M; Harshbarger, F C

1966-02-01

The sodium line reversal technique was used to determine the reversal temperature profile across the exit of small rockets. Measurements were made on one 73-kg thrust rocket, and two 23-kg thrust rockets with different injectors. The large rocket showed little variation of reversal temperature across the plume. However, the 23-kg rockets both showed a large decrease of reversal temperature from the axis to the edge of the plume. In addition, the sodium line reversal technique of temperature measurement was compared with an infrared technique developed in these laboratories.

Shaving

MedlinePlus

... the shower or the tub or with water running from the sink. Traditional razors will give you a close, smooth shave. There are two types you can choose from – one that is completely disposable (meaning you throw away the entire razor and the blade), and another, where you just throw away the ...

Ground Reaction Forces and Throwing Performance in Elite and Novice Players in Two Types of Handball Shot

PubMed Central

Rousanoglou, Elissavet; Noutsos, Konstantinos; Bayios, Ioannis; Boudolos, Konstantinos

2014-01-01

The purpose of this study was to examine the differences in the ground reaction force (GRF) patterns between elite and novice players during two types of handball shots, as well as the relationships between throwing performance and the GRF variables. Ball velocity and throwing accuracy were measured during jump shots and 3-step shots performed by 15 elite and 15 novice players. The GRF pattern was recorded for the vertical and the anterior-posterior GRF components (Kistler forceplate type-9281, 750Hz). One-way ANOVA was used for the group differences and the Pearson coefficient for the correlation between throwing performance and GRF variables (SPSS 21.0, p ≤ 0.05). The elite players performed better in both types of shot. Both groups developed consistent and similar GRF patterns, except for the novices’ inconsistent Fz pattern in the 3-step shot. The GRF variables differed significantly between groups in the 3-step shot (p ≤ 0.05). Significant correlations were found only for ball velocity and predominantly for the novice players during the 3-step shot (p ≤ 0.05). The results possibly highlight a shortage in the novice ability to effectively reduce their forward momentum so as to provide a stable base of support for the momentum transfer up the kinetic chain, a situation that may predispose athletes to injury. PMID:25031672

Ground reaction forces and throwing performance in elite and novice players in two types of handball shot.

PubMed

Rousanoglou, Elissavet; Noutsos, Konstantinos; Bayios, Ioannis; Boudolos, Konstantinos

2014-03-27

The purpose of this study was to examine the differences in the ground reaction force (GRF) patterns between elite and novice players during two types of handball shots, as well as the relationships between throwing performance and the GRF variables. Ball velocity and throwing accuracy were measured during jump shots and 3-step shots performed by 15 elite and 15 novice players. The GRF pattern was recorded for the vertical and the anterior-posterior GRF components (Kistler forceplate type-9281, 750Hz). One-way ANOVA was used for the group differences and the Pearson coefficient for the correlation between throwing performance and GRF variables (SPSS 21.0, p ≤ 0.05). The elite players performed better in both types of shot. Both groups developed consistent and similar GRF patterns, except for the novices' inconsistent Fz pattern in the 3-step shot. The GRF variables differed significantly between groups in the 3-step shot (p ≤ 0.05). Significant correlations were found only for ball velocity and predominantly for the novice players during the 3-step shot (p ≤ 0.05). The results possibly highlight a shortage in the novice ability to effectively reduce their forward momentum so as to provide a stable base of support for the momentum transfer up the kinetic chain, a situation that may predispose athletes to injury.

A biomechanical study of laparoscopic 4S-modified Roeder and Weston knot strength in 3-0 polyglactin 910 and 3-0 polydioxanone.

PubMed

Fugazzi, Russell W; Fransson, Boel A; Curran, Katie M; Davis, Howard M; Gay, John M

2013-02-01

To (1) evaluate biomechanical strength of 4 different laparoscopic knots using 2 suture types, and (2) evaluate carotid artery ligature bursting pressure of 2 knots using a single suture type. Biomechanical materials testing. Suture material (3-0 polydioxanone, 3-0 polyglactin 910). Four knot types were tested: 4S-modified Roeder (4SMR) Weston plus 3 square throws (W3S); Weston plus 3 granny throws (W3G); and a 4 square throw knot as a control (control); 24 specimens of each knot type were tied with 3-0 polyglactin 910 and 24 of 3 knot types (4SMR, W3S, control) were tied with 3-0 polydioxanone. Suture loop constructs were tested to 3 mm displacement failure and ultimate failure. Carotid artery ligation bursting pressure was tested using 10 samples each of 4SMR and W3S knots with 3-0 polyglactin 910. The W3S, W3G, and controls were similar. The 4SMR was similar to W3S using 3-0 PDS but the 4SMR had lower load to failure and greater elongation than the Weston using 3-0 polyglactin 910. The 4SMR had a higher slippage rate with 3-0 polyglactin 910. All ligatures withstood supraphysiologic pressures. Surgeons using 3-0 polyglactin 910 should consider using the Weston knot with added throws during laparoscopic procedures. © Copyright 2012 by The American College of Veterinary Surgeons.

Biomimetics of throwing at basketball

NASA Astrophysics Data System (ADS)

Merticaru, E.; Budescu, E.; Iacob, R. M.

2016-08-01

The paper deals with the inverse dynamics of a kinematic chain of the human upper limb when throwing the ball at the basketball, aiming to calculate the torques required to put in action the technical system. The kinematic chain respects the anthropometric features regarding the length and mass of body segments. The kinematic parameters of the motion were determined by measuring the angles of body segments during a succession of filmed pictures of a throw, and the interpolation of these values and determination of the interpolating polynomials for each independent geometric coordinate. Using the Lagrange equations, there were determined the variations with time of the required torques to put in motion the kinematic chain of the type of triple physical pendulum. The obtained values show, naturally, the fact that the biggest torque is that for mimetic articulation of the shoulder, being comparable with those obtained by the brachial biceps muscle of the analyzed human subject. Using the obtained data, there can be conceived the mimetic technical system, of robotic type, with application in sports, so that to perform the motion of ball throwing, from steady position, at the basket.

Relationship between grip, pinch strengths and anthropometric variables, types of pitch throwing among Japanese high school baseball pitchers.

PubMed

Tajika, Tsuyoshi; Kobayashi, Tsutomu; Yamamoto, Atsushi; Shitara, Hitoshi; Ichinose, Tsuyoshi; Shimoyama, Daisuke; Okura, Chisa; Kanazawa, Saeko; Nagai, Ayako; Takagishi, Kenji

2015-03-01

Grip and pinch strength are crucially important attributes and standard parameters related to the functional integrity of the hand. It seems significant to investigate normative data for grip and pinch strength of baseball players to evaluate their performance and condition. Nevertheless, few reports have explained the association between grip and pinch strength and anthropometric variables and types of pitch throwing for baseball pitchers. The aim of this study was to measure and evaluate clinical normative data for grip and tip, key, palmar pinch strength and to assess the relationship between these data and anthropometric variables and types of pitch throwing among Japanese high-school baseball pitchers. One hundred-thirty three healthy high school baseball pitchers were examined and had completed a self-administered questionnaire including items related to age, hand dominance, throwing ratio of type of pitch. A digital dynamometer was used to measure grip strength and a pinch gauge to measure tip, key and palmer pinch in both dominant and nondominant side. Body composition was measured by the multi frequency segmental body composition analyzer. Grip strength and tip and palmer pinch strength in dominant side were statistically greater than them in nondominant side (P < 0.05). There were significant associations between grip strength and height (r = 0.33, P < 0.001), body mass (r = 0.50, P < 0.001), BMI (r = 0.37, P < 0.001), muscle mass of upper extremity (r = 0.56, P < 0.001), fat free mass (r = 0.57, P < 0.001), fat mass (r = 0.22, P < 0.05) in dominant side. A stepwise multiple regression analysis revealed that fat free mass and tip, palmer, key pinch strength were predictors of grip strength in dominant side. No statistical significant correlations were found between the throwing ratio of types of pitches thrown and grip strength and tip, key, palmar pinch strength. Our result provides normative values and evidences for grip and pinch strengths in high school baseball pitchers.

Determinant Factors of Physical Performance and Specific Throwing in Handball Players of Different Ages.

PubMed

Ortega-Becerra, Manuel; Pareja-Blanco, Fernando; Jiménez-Reyes, Pedro; Cuadrado-Peñafiel, Víctor; González-Badillo, Juan J

2018-06-01

Ortega-Becerra, M, Pareja-Blanco, F, Jiménez-Reyes, P, Cuadrado-Peñafiel, V, and González-Badillo, JJ. Determinant factors of physical performance and specific throwing in handball players of different ages. J Strength Cond Res 32(6): 1778-1786, 2018-This study aimed to analyze various fitness qualities in handball players of different ages and to determine the relationships between these parameters and throwing velocity. A total of 44 handball players participated, pooled by age groups: professional (ELITE, n = 13); under-18 (U18, n = 16); under-16 (U16, n = 15). The following tests were completed: 20-m running sprints; countermovement jumps (CMJs); jump squat to determine the load that elicited ∼20 cm jump height (JSLOAD-20 cm); a progressive loading test in full squat and bench press to determine the load that elicited ∼1 m·s (SQ-V1-LOAD and BP-V1-LOAD); and handball throwing (jump throw and 3-step throw). ELITE showed greater performance in almost all sprint distances, CMJ, JSLOAD-20 cm, and bench press strength than U18 and U16. The differences between U18 and U16 were unclear for these variables. ELITE also showed greater (p < 0.001) performance for squat strength and throwing than U18 and U16, and U18 attained greater performance (p ≤ 0.05) for these variables than U16. Throwing performance correlated (p ≤ 0.05) with sprint times (r = -0.31; -0.51) and jump ability (CMJ: r = 0.39; 0.56 and JSLOAD-20 cm: r = 0.57; 0.60). Muscle strength was also associated (p < 0.001) with both types of throw (SQ-V1-LOAD: r = 0.66; 0.76; and BP-V1-LOAD: r = 0.33; 0.70). These results indicate that handball throwing velocity is strongly associated with lower-limb strength, although upper-limb strength, jumping and sprint capacities also play a relevant role in throwing performance, suggesting the need for coaches to include proper strength programs to improve handball players' throwing velocity.

Comparison of three types of full‐body compression garments on throwing and repeat‐sprint performance in cricket players

PubMed Central

Duffield, Rob; Portus, Marc

2007-01-01

Objective To compare the effects of three types of full‐body compression garments (Skins, Adidas and Under Armour) on repeat‐sprint and throwing performance in cricket players. Methods Following familiarisation, 10 male cricket players performed four randomised exercise sessions (3 garments and a control). Each session involved a 30 min repeat‐sprint exercise protocol comprising 20 m sprints every minute, separated by submaximal exercise. Throwing tests included a pre‐exercise and a postexercise maximal distance test and accuracy throwing tests. During each session, measures of heart rate, skin temperature, change in body mass, rate of perceived exertion and perceived muscle soreness were recorded. Capillary blood samples were analysed before and after exercise for lactate, pH, O2 saturation and O2 partial pressure, and 24 h after exercise for creatine kinase (CK). Ratings of perceived muscle soreness were also obtained 24 h after exercise. Results No significant differences (p>0.05) were evident in repeat‐sprint performance (10 m, 20 m time or total submaximal distance covered) or throwing performance (maximum distance or accuracy). No significant differences (p>0.05) were observed in heart rate, body mass change or blood measures during exercise. Significant differences (p<0.05) were observed by way of higher mean skin temperature, lower 24 h postexercise CK values and lower 24 h postexercise ratings of muscle soreness when wearing compression garments. Analysis between respective brands of compression garments revealed no statistical differences (p>0.05). Conclusions No benefit was noted when wearing compression garments for repeat‐sprint or throwing performance; however, the use of the garments as a recovery tool, when worn after exercise, may be beneficial to reduce postexercise trauma and perceived muscle soreness. PMID:17341589

Comparison of three types of full-body compression garments on throwing and repeat-sprint performance in cricket players.

PubMed

Duffield, Rob; Portus, Marc

2007-07-01

To compare the effects of three types of full-body compression garments (Skins, Adidas and Under Armour) on repeat-sprint and throwing performance in cricket players. Following familiarisation, 10 male cricket players performed four randomised exercise sessions (3 garments and a control). Each session involved a 30 min repeat-sprint exercise protocol comprising 20 m sprints every minute, separated by submaximal exercise. Throwing tests included a pre-exercise and a postexercise maximal distance test and accuracy throwing tests. During each session, measures of heart rate, skin temperature, change in body mass, rate of perceived exertion and perceived muscle soreness were recorded. Capillary blood samples were analysed before and after exercise for lactate, pH, O(2) saturation and O(2) partial pressure, and 24 h after exercise for creatine kinase (CK). Ratings of perceived muscle soreness were also obtained 24 h after exercise. No significant differences (p>0.05) were evident in repeat-sprint performance (10 m, 20 m time or total submaximal distance covered) or throwing performance (maximum distance or accuracy). No significant differences (p>0.05) were observed in heart rate, body mass change or blood measures during exercise. Significant differences (p<0.05) were observed by way of higher mean skin temperature, lower 24 h postexercise CK values and lower 24 h postexercise ratings of muscle soreness when wearing compression garments. Analysis between respective brands of compression garments revealed no statistical differences (p>0.05). No benefit was noted when wearing compression garments for repeat-sprint or throwing performance; however, the use of the garments as a recovery tool, when worn after exercise, may be beneficial to reduce postexercise trauma and perceived muscle soreness.

The High Altitude Balloon Experiment demonstration of acquisition, tracking, and pointing technologies (HABE-ATP)

NASA Astrophysics Data System (ADS)

Dimiduk, D.; Caylor, M.; Williamson, D.; Larson, L.

1995-01-01

The High Altitude Balloon Experiment demonstration of Acquisition, Tracking, and Pointing (HABE-ATP) is a system built around balloon-borne payload which is carried to a nominal 26-km altitude. The goal is laser tracking thrusting theater and strategic missiles, and then pointing a surrogate laser weapon beam, with performance levels end a timeline traceable to operational laser weapon system requirements. This goal leads to an experiment system design which combines hardware from many technology areas: an optical telescope and IR sensors; an advanced angular inertial reference; a flexible multi-level of actuation digital control system; digital tracking processors which incorporate real-time image analysis and a pulsed, diode-pumped solid state tracking laser. The system components have been selected to meet the overall experiment goals of tracking unmodified boosters at 50- 200 km range. The ATP system on HABE must stabilize and control a relative line of sight between the platform and the unmodified target booster to a 1 microrad accuracy. The angular pointing reference system supports both open loop and closed loop track modes; GPS provides absolute position reference. The control system which positions the line of sight for the ATP system must sequence through accepting a state vector handoff, closed-loop passive IR acquisition, passive IR intermediate fine track, active fine track, and then finally aimpoint determination and maintenance modes. Line of sight stabilization to fine accuracy levels is accomplished by actuating wide bandwidth fast steering mirrors (FSM's). These control loops off-load large-amplitude errors to the outer gimbal in order to remain within the limited angular throw of the FSM's. The SWIR acquisition and MWIR intermediate fine track sensors (both PtSi focal planes) image the signature of the rocket plume. After Hard Body Handover (HBHO), active fine tracking is conducted with a visible focal plane viewing the laser-illuminated target rocket body. The track and fire control performance must be developed to the point that an aimpoint can be selected, maintained, and then track performance scored with a low-power 'surrogate' weapon beam. Extensive instrumentation monitors not only the optical sensors and the video data, but all aspects of each of the experiment subsystems such as the control system, the experiment flight vehicle, and the tracker. Because the system is balloon-borne and recoverable, it is expected to fly many times during its development program.

Rockets using Liquid Oxygen

NASA Technical Reports Server (NTRS)

Busemann, Adolf

1947-01-01

It is my task to discuss rocket propulsion using liquid oxygen and my treatment must be highly condensed for the ideas and experiments pertaining to this classic type of rocket are so numerous that one could occupy a whole morning with a detailed presentation. First, with regard to oxygen itself as compared with competing oxygen carriers, it is known that the liquid state of oxygen, in spite of the low boiling point, is more advantageous than the gaseous form of oxygen in pressure tanks, therefore only liquid oxygen need be compared with the oxygen carriers. The advantages of liquid oxygen are absolute purity and unlimited availability at relatively small cost in energy. The disadvantages are those arising from the impossibility of absolute isolation from heat; consequently, allowance must always be made for a certain degree of vaporization and only vented vessels can be used for storage and transportation. This necessity alone eliminates many fields of application, for example, at the front lines. In addition, liquid oxygen has a lower specific weight than other oxygen carriers, therefore many accessories become relatively larger and heavier in the case of an oxygen rocket, for example, the supply tanks and the pumps. The advantages thus become effective only in those cases where definitely scheduled operation and a large ground organization are possible and when the flight requires a great concentration of energy relative to weight. With the aim of brevity, a diagram of an oxygen rocket will be presented and the problem of various component parts that receive particularly thorough investigation in this classic case but which are also often applicable to other rocket types will be referred to.

Differences in anthropometric characteristics in relation to throwing velocity and competitive level in professional male team handball: a tool for talent profiling.

PubMed

Fieseler, Georg; Hermassi, Souhail; Hoffmeyer, Birgit; Schulze, Stephan; Irlenbusch, Lars; Bartels, Thomas; Delank, Karl-Stefan; Laudner, Kevin G; Schwesig, René

2017-01-01

The primary aim of the study was to examine the anthropometric characteristics as well as throwing and sprinting performance of professional handball players classified by playing position and competition level. 21 male players (age: 25.2±5.1 years) from the first German handball league (FGL) and 34 male players (age: 26.1±4.1 years) from the third German handball league (TGL) were categorized as backs, pivots, wings and goalkeepers. Measurements included anthropometric data (height, mass and body mass index (BMI)), throwing and sprinting performance selected out of a complex handball test (HBCT), which was conducted twice (2 rounds). During the HBCT, the subjects performed two sprints (10, 20 m), two standing throws with run-up (ST) and four vertical jump throws (VJT) over a hurdle (20 cm) with and without precision for goal shot. The anthropometric data revealed a significantly (P=0.038 and η2=0.079) shorter body height for TGL than for FGL players. In the cohort of first league athletes the pivots were the tallest (1.98±0.04 m), backs in the third league showed the maximum body height (1.90±0.05 m). Regarding body mass, pivots were the heaviest players independent from the league membership. The FGL players showed a significantly (P<0.05 and η2>0.10) higher throwing velocity in all type of throws. Body height was significantly related to ST (r=0.53) and VJT (r=0.52) in the first round of HBCT but only for the FGL athletes. Throwing velocity was also correlated with BMI (r=-0.50) among the TGL players. Substantial differences of body characteristics, throwing and sprinting performance between playing positions and competitive levels underline the importance of a careful scouting and position-specific training for professional handball players.

Frequency and number of ultrasound lung rockets (B-lines) using a regionally based lung ultrasound examination named vet BLUE (veterinary bedside lung ultrasound exam) in dogs with radiographically normal lung findings.

PubMed

Lisciandro, Gregory R; Fosgate, Geoffrey T; Fulton, Robert M

2014-01-01

Lung ultrasound is superior to lung auscultation and supine chest radiography for many respiratory conditions in human patients. Ultrasound diagnoses are based on easily learned patterns of sonographic findings and artifacts in standardized images. By applying the wet lung (ultrasound lung rockets or B-lines, representing interstitial edema) versus dry lung (A-lines with a glide sign) concept many respiratory conditions can be diagnosed or excluded. The ultrasound probe can be used as a visual stethoscope for the evaluation of human lungs because dry artifacts (A-lines with a glide sign) predominate over wet artifacts (ultrasound lung rockets or B-lines). However, the frequency and number of wet lung ultrasound artifacts in dogs with radiographically normal lungs is unknown. Thus, the primary objective was to determine the baseline frequency and number of ultrasound lung rockets in dogs without clinical signs of respiratory disease and with radiographically normal lung findings using an 8-view novel regionally based lung ultrasound examination called Vet BLUE. Frequency of ultrasound lung rockets were statistically compared based on signalment, body condition score, investigator, and reasons for radiography. Ten left-sided heart failure dogs were similarly enrolled. Overall frequency of ultrasound lung rockets was 11% (95% confidence interval, 6-19%) in dogs without respiratory disease versus 100% (95% confidence interval, 74-100%) in those with left-sided heart failure. The low frequency and number of ultrasound lung rockets observed in dogs without respiratory disease and with radiographically normal lungs suggests that Vet BLUE will be clinically useful for the identification of canine respiratory conditions. © 2014 American College of Veterinary Radiology.

MEMS, Ka-Band Single-Pole Double-Throw (SPDT) Switch for Switched Line Phase Shifters

NASA Technical Reports Server (NTRS)

Scardelletti, Maximilian C.; Ponchak, George E.; Varaljay, Nicholas C.

2002-01-01

Ka-band MEMS doubly anchored cantilever beam capacitive shunt devices are used to demonstrate a MEMS SPDT switch fabricated on high resistivity silicon (HRS) utilizing finite ground coplanar waveguide (FGC) transmission lines. The SPDT switch has an insertion loss (IL), return loss (RL), and isolation of 0.3dB, 40dB, and 30 dB, respectively at Ka-band.

The Relationship of Throwing Arm Mechanics and Elbow Varus Torque: Within-Subject Variation for Professional Baseball Pitchers Across 82,000 Throws.

PubMed

Camp, Christopher L; Tubbs, Travis G; Fleisig, Glenn S; Dines, Joshua S; Dines, David M; Altchek, David W; Dowling, Brittany

2017-11-01

Likely due to the high level of strain exerted across the elbow during the throwing motion, elbow injuries are on the rise in baseball. To identify at-risk athletes and guide postinjury return-to-throw programs, a better understanding of the variables that influence elbow varus torque is desired. To describe the within-subject relationship between elbow varus torque and arm slot and arm rotation in professional baseball pitchers. Descriptive laboratory study. A total of 81 professional pitchers performed 82,000 throws while wearing a motusBASEBALL sensor and sleeve. These throws represented a combination of throw types, such as warm-up/catch, structured long-toss, bullpen throwing from a mound, and live game activity. Variables recorded for each throw included arm slot (angle of the forearm relative to the ground at ball release), arm speed (maximal rotational velocity of the forearm), arm rotation (maximal external rotation of the throwing arm relative to the ground), and elbow varus torque. Linear mixed-effects models and likelihood ratio tests were used to estimate the relationship between elbow varus torque and arm slot, arm speed, and arm rotation within individual pitchers. All 3 metrics-arm slot (χ 2 = 428, P < .001), arm speed (χ 2 = 57,683, P < .001), and arm rotation (χ 2 = 1392, P < .001)-were found to have a significant relationship with elbow varus torque. Within individual athletes, a 1-N.m increase in elbow varus torque was associated with a 13° decrease in arm slot, a 116 deg/s increase in arm speed, and an 8° increase in arm rotation. Elbow varus torque increased significantly as pitchers increased their arm rotation during the arm cocking phase, increased the rotational velocity of their arm during the arm acceleration phase of throwing, and decreased arm slot at ball release. Thus, shoulder flexibility, arm speed, and elbow varus torque (and likely injury risk) are interrelated and should be considered collectively when treating pitchers. It is well established that elbow varus torque is related to ulnar collateral ligament injuries in overhead throwers. This study describes the relationship of arm slot, arm speed, and arm rotation to elbow varus torque in an attempt to identify modifiable risk factors for injury.

An ultrashort throw ratio projection lens design based on a catadioptric structure

NASA Astrophysics Data System (ADS)

Wang, Hsiu-Cheng; Pan, Jui-Wen

2018-07-01

In this paper, we present a rotational symmetry for an ultrashort throw (UST) lens with offset field. The UST lens has a throw ratio of 0.23 and a total track of 195 mm. The optical elements of the UST lens are comprised of two parts. First, a catadioptric projection lens where the catadioptric function permits reaching an ultrashort throw ratio, short total track, while at the same time requiring fewer lens elements. The second part is a collimating lens which takes advantage of the telecentric condition to generate uniform total internal reflection (TIR) in the TIR prism. With this design, an effective focal length of -1.96 mm and a f-number of 2.4 can be obtained. The root mean square spot size and lateral colour of all fields are smaller than one pixel in size. The maximum optical distortion of -0.97% and TV distortion of 0.2% are acceptable. In terms of image quality, the modulation transfer function (MTF) values for all fields are above 0.65 at 0.245 line pairs/mm. Even when the tolerance error is considered, the MTF values for all fields are still above 0.3. The suitability of the novel UST lens design for projection applications is discussed.

Rocket spectroscopy of zeta Orionis.

NASA Technical Reports Server (NTRS)

Smith, A. M.

1972-01-01

Analysis of a spectrum of zeta Ori extending from 922 to 1453 A with approximately 0.8 A resolution recorded at rocket altitudes. All lines used in existing models of stellar atmospheres appear in the recorded spectrum with the exception of those masked by telluric N2 or strong P Cygni-type profiles and by an O V line at 1371.29 A. Fifteen multiplets of subordinate lines have been reliably identified, indicating an approximate range of excitation from 0 to 50 eV. Transitions in C III (1176 A), N III (991 A), N V (1239, 1243 A), O VI (1032, 1038 A), Si IV (1394, 1403 A), S IV (1063, 1074 A), and S VI (933, 944 A) have been observed as P Cygni-type profiles presumably arising in a circumstellar envelope. The degree of ionization, transitions present, and mean radial velocities are all consistent with viewing the envelope as a hot (about 100,000 K), rarefied plasma in which collisional ionization is important. Interstellar lines in C I (1277, 1280 A), C II (1036, 1334 A), N I (1134-1135 A), N I (1200-1201 A), N II (1084-1086 A), O I (1302, 1305 A), Si II (1190, 1193 A), Si II (1260 A), and Si II (1304 A) have been definitely identified. Other transitions in Ar II, S I, C I, and Fe II are tentatively identified. The equivalent width of the L alpha line is found to be 10.4 plus or minus 1.6 A, corresponding to a columnar density of 2.0 plus or minus 0.7 x 10 to the 20th per cu cm.

In Vitro Evaluation of the Size, Knot Holding Capacity, and Knot Security of the Forwarder Knot Compared to Square and Surgeon's Knots Using Large Gauge Suture.

PubMed

Gillen, Alex M; Munsterman, Amelia S; Hanson, R Reid

2016-11-01

To investigate the strength, size, and holding capacity of the self-locking forwarder knot compared to surgeon's and square knots using large gauge suture. In vitro mechanical study. Knotted suture. Forwarder, surgeon's, and square knots were tested on a universal testing machine under linear tension using 2 and 3 USP polyglactin 910 and 2 USP polydioxanone. Knot holding capacity (KHC) and mode of failure were recorded and relative knot security (RKS) was calculated as a percentage of KHC. Knot volume and weight were assessed by digital micrometer and balance, respectively. ANOVA and post hoc testing were used tocompare strength between number of throws, suture, suture size, and knot type. P<.05 was considered significant. Forwarder knots had a higher KHC and RKS than surgeon's or square knots for all suture types and number of throws. No forwarder knots unraveled, but a proportion of square and surgeon's knots with <6 throws did unravel. Forwarder knots had a smaller volume and weight than surgeon's and square knots with equal number of throws. The forwarder knot of 4 throws using 3 USP polyglactin 910 had the highest KHC, RKS, and the smallest size and weight. Forwarder knots may be an alternative for commencing continuous patterns in large gauge suture, without sacrificing knot integrity, but further in vivo and ex vivo testing is required to assess the effects of this sliding knot on tissue perfusion before clinical application. © Copyright 2016 by The American College of Veterinary Surgeons.

Mean Line Pump Flow Model in Rocket Engine System Simulation

NASA Technical Reports Server (NTRS)

Veres, Joseph P.; Lavelle, Thomas M.

2000-01-01

A mean line pump flow modeling method has been developed to provide a fast capability for modeling turbopumps of rocket engines. Based on this method, a mean line pump flow code PUMPA has been written that can predict the performance of pumps at off-design operating conditions, given the loss of the diffusion system at the design point. The pump code can model axial flow inducers, mixed-flow and centrifugal pumps. The code can model multistage pumps in series. The code features rapid input setup and computer run time, and is an effective analysis and conceptual design tool. The map generation capability of the code provides the map information needed for interfacing with a rocket engine system modeling code. The off-design and multistage modeling capabilities of the code permit parametric design space exploration of candidate pump configurations and provide pump performance data for engine system evaluation. The PUMPA code has been integrated with the Numerical Propulsion System Simulation (NPSS) code and an expander rocket engine system has been simulated. The mean line pump flow code runs as an integral part of the NPSS rocket engine system simulation and provides key pump performance information directly to the system model at all operating conditions.

Liquid Rocket Lines, Bellows, Flexible Hoses, and Filters

NASA Technical Reports Server (NTRS)

1977-01-01

Fluid-flow components in a liquid propellant rocket engine and the rocket vehicle which it propels are interconnected by lines, bellows, and flexible hoses. Elements involved in the successful design of these components are identified and current technologies pertaining to these elements are reviewed, assessed, and summarized to provide a technology base for a checklist of rules to be followed by project managers in guiding a design or assessing its adequacy. Recommended procedures for satisfying each of the design criteria are included.

Early Rockets

NASA Image and Video Library

2004-04-15

By 1870, American and British inventors had found other ways to use rockets. For example, the Congreve rocket was capable of carrying a line over 1,000 feet to a stranded ship. In 1914, an estimated 1,000 lives were saved by this technique.

Despin System for Hydrogen Tank in the Propulsion Systems Laboratory

NASA Image and Video Library

1962-04-21

Mechanic Howard Wine inspects the setup of a spin isolator in Cell 2 of the Propulsion Systems Laboratory at the National Aeronautics and Space Administration (NASA) Lewis Research Center. Photographer Al Jecko filmed the proceedings. This test was unique in that the chamber’s altitude system was used, but not its inlet air flow. The test was in preparation for an upcoming launch of modified liquid hydrogen propellant tank on a sounding rocket. This Weightlessness Analysis Sounding Probe (WASP) was part of Lewis investigation into methods for controlling partially filled liquid hydrogen fuel tanks during flight. Second-stage rockets, the Centaur in particular, were designed to stop their engines and coast, then restart them when needed. During this coast period, the propellant often shifted inside the tank. This movement could throw the rocket off course or result in the sloshing of fuel away from the fuel pump. Wine was one of only three journeymen mechanics at Lewis when he was hired in January 1954. He spent his first decade in the Propulsion Systems Laboratory and was soon named a section head. Wine went on to serve as Assistant Division Chief and later served as an assistant to the director. Jecko joined the center in 1947 as a photographer and artist. He studied at the Cleveland School or Art and was known for his cartoon drawing. He worked at the center for 26 years.

Data-Based Interval Throwing Programs for Collegiate Softball Players

PubMed Central

Axe, Michael J.; Windley, Thomas C.; Snyder-Mackler, Lynn

2002-01-01

Objective: To construct interval throwing programs followed by a simulated game for collegiate softball players at all positions. The programs are intended to be used as functional progressions within a comprehensive rehabilitation program for an injured athlete or to augment off-season conditioning workouts. Design and Setting: We collected data over a single season of National Collegiate Athletic Association softball at the University of Delaware and Goldey Beacom College. We observed 220 half-innings of play and 2785 pitches during data collection. Subjects: The subjects were collegiate-level softball players at all positions of play. Measurements: We recorded the number of pitches for pitchers. For catchers, we recorded the number of sprints to back up a play, time in the squat stance, throws back to the pitcher, and the perceived effort and distance of all other throws. We also collected the perceived effort and distance of all throws for infielders and outfielders. Results: Pitchers threw an average of 89.61 pitches per game; catchers were in the squat stance 14.13 minutes per game; infielders threw the ball between 4.28 times per game and 6.30 times per game; and outfielders threw distances of up to 175 feet. Conclusions: We devised the interval throwing programs from the data collected, field dimensions, the types of injuries found to occur in softball, and a general understanding of tissue healing. We designed programs that allow a safe and efficient progressive return to sport. PMID:12937435

Two-Dimensional Motions of Rockets

ERIC Educational Resources Information Center

Kang, Yoonhwan; Bae, Saebyok

2007-01-01

We analyse the two-dimensional motions of the rockets for various types of rocket thrusts, the air friction and the gravitation by using a suitable representation of the rocket equation and the numerical calculation. The slope shapes of the rocket trajectories are discussed for the three types of rocket engines. Unlike the projectile motions, the…

32 CFR 552.184 - Policy.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 3 2011-07-01 2009-07-01 true Policy. 552.184 Section 552.184 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES..., it is illegal and a violation of existing law to throw fishing line, paper, plastic materials, and...

32 CFR 552.184 - Policy.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 3 2012-07-01 2009-07-01 true Policy. 552.184 Section 552.184 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES..., it is illegal and a violation of existing law to throw fishing line, paper, plastic materials, and...

32 CFR 552.184 - Policy.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 3 2013-07-01 2013-07-01 false Policy. 552.184 Section 552.184 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES..., it is illegal and a violation of existing law to throw fishing line, paper, plastic materials, and...

Age-associated power decline from running, jumping, and throwing male masters world records.

PubMed

Gava, Paolo; Kern, Helmut; Carraro, Ugo

2015-01-01

BACKGROUND/STUDY CONTEXT: The capacity to perform everyday tasks is directly related to the muscular power the body can develop (see Appendix). The age-related loss of power is a fact, but the characterization or the rate of muscle power loss remains an open issue. Data useful to study the decline of the skeletal muscles power are largely available from sources other than medical tests, e.g., from track and field competitions of Masters athletes. The aim of our study is to identify the age-related decline trend of the power developed by the athletes in carrying out the track and field events. Absolute male world records of 16 events were collected along with world records of male Masters categories. Performance was normalized with respect to the absolute record; the performance of various age groups is consequently represented by a number ranging from 1 (world absolute records) to 0 (null performance). The performance of a jumping event is transformed into a parameter proportional to the power developed by the athletes: the displacement of the center of gravity of the athlete. Throwing events are further normalized for the decreasing weight of the implements with the increasing age of the Masters athletes. Most track and field events show a linear decline to 70 years. The annual rate of power decline for all the events (running, throwing, and jumping), using a simplified synthesis, is 1.25% per year. The events that involve mostly upper limbs (shot put, javelin throw) show a higher rate of decline (1.4% per year) compared to those where the lower limbs are mostly involved (long jump 1.1%, track events 0.6-0.7% per year). This analysis of muscle power decline is only partially in line with the results of works based on clinical tests. A clarification of the reasons for such discrepancy may provide clinically significant information. Human power decline in Masters athletes was analyzed, adopting a coherent approach based on an extended database. Skeletal muscle power starts declining after the age of 30, with slight variations depending on the events. This conclusion is in line with only some of the previous studies. The various trend lines point to 0 at the age of 110 years, which is in line with the present human survival age. The study can be further developed with a suitable database for male and female Masters performances to facilitate longitudinal studies, which are currently lacking.

Miniature Autonomous Rocket Recovery System (MARRS)

DTIC Science & Technology

2011-05-01

composed of approximately 4 to 6 cubic centimeters of FFFF black powder. C. Rocket System Structure The rocket body was an epoxy-laden phenolic ... Kevlar line upon which was the lower main parachute; a 50” Rocket Rage Parachute. The booster had a 70” Rocket Rage parachute. In order to protect...the parachutes from burns, the parachutes were wrapped in protective Kevlar cloth and a layer of flame-retardant cellulose was packed in between the

Radiation/convection coupling in rocket motors and plumes

NASA Technical Reports Server (NTRS)

Farmer, R. C.; Saladino, A. J.

1993-01-01

The three commonly used propellant systems - H2/O2, RP-1/O2, and solid propellants - primarily radiate as molecular emitters, non-scattering small particles, and scattering larger particles, respectively. Present technology has accepted the uncoupling of the radiation analysis from that of the flowfield. This approximation becomes increasingly inaccurate as one considers plumes, interior rocket chambers, and nuclear rocket propulsion devices. This study will develop a hierarchy of methods which will address radiation/convection coupling in all of the aforementioned propulsion systems. The nature of the radiation/convection coupled problem is that the divergence of the radiative heat flux must be included in the energy equation and that the local, volume-averaged intensity of the radiation must be determined by a solution of the radiative transfer equation (RTE). The intensity is approximated by solving the RTE along several lines of sight (LOS) for each point in the flowfield. Such a procedure is extremely costly; therefore, further approximations are needed. Modified differential approximations are being developed for this purpose. It is not obvious which order of approximations are required for a given rocket motor analysis. Therefore, LOS calculations have been made for typical rocket motor operating conditions in order to select the type approximations required. The results of these radiation calculations, and the interpretation of these intensity predictions are presented herein.

46 CFR 131.530 - Abandon-ship training and drills.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Abandon-ship training and drills. 131.530 Section 131... OPERATIONS Tests, Drills, and Inspections § 131.530 Abandon-ship training and drills. (a) Material for... rescue gear (slings, baskets, stretchers) and vessel's line-throwing apparatus. (b) An abandon-ship drill...

46 CFR 131.530 - Abandon-ship training and drills.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Abandon-ship training and drills. 131.530 Section 131... OPERATIONS Tests, Drills, and Inspections § 131.530 Abandon-ship training and drills. (a) Material for... rescue gear (slings, baskets, stretchers) and vessel's line-throwing apparatus. (b) An abandon-ship drill...

46 CFR 131.530 - Abandon-ship training and drills.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Abandon-ship training and drills. 131.530 Section 131... OPERATIONS Tests, Drills, and Inspections § 131.530 Abandon-ship training and drills. (a) Material for... rescue gear (slings, baskets, stretchers) and vessel's line-throwing apparatus. (b) An abandon-ship drill...

The Throws: Contemporary Theory, Technique and Training.

ERIC Educational Resources Information Center

Wilt, Fred, Ed.

This compilation of articles covers the subject of four throwing events--shot put, discus throw, hammer throw, and javelin throw. The history of the art and science of throwing is traced from ancient to modern times in the introduction. Theories on training and techniques of throwing are presented in essays contributed by coaches from the United…

[Experimental studies on the wounding capacity of recently developed shuriken/throwing stars and their legal categorization--an interdisciplinary view].

PubMed

Kettner, Mattias; Gade, Gunther; Ramsthaler, Frank; Shah, Sanjai; Pape, Andreas; Theisen, Alf; Schmidt, Peter

2010-01-01

Shuriken/throwing stars are traditional Japanese weapons for close combat situations. They vary greatly in shape and mode of action. Due to their wounding capacity traditional shuriken made of steel were prohibited in Germany in the 1980's. In the present study three recently developed types of shuriken were examined to determine their wounding capacity. Type 1 was made of plastic, whereas type 2 was a so-called cyclone shuriken equipped with three knives protruding from a discoidal center due to centrifugal force during the flight. Type 3 consisted of three traditional metal shuriken with blunt edges and peaks produced for decorative purposes. Experiments using pig carcasses were carried out for types 1 and 2. An experiment using human skin was performed with type 3 shuriken. An experienced thrower performed throws from a distance of 1, 2, 3, and 4 m with the shuriken made of plastic. For the cyclone shuriken a distance of 4 m was chosen to ensure the unfolding of the shuriken during flight. Type 3 shuriken were tested using a distance of 2 m. Penetration depths of the shuriken made of plastic reached up to 8 mm in pig skin. The experiment with the cyclone shuriken revealed a penetration depth of up to 2.5 cm cutting through the entire abdominal tissue and opening up an intestinal loop whereas type 3 shuriken yielded maximal penetration depths between 0.9 and 2.3 cm. This study indicates that all three types of shuriken may inflict lethal wounds upon opponents in close combat. The findings of this study should promote a public discussion whether the ban on traditional shuriken should be extended to the recently developed types.

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.

Randomized in vitro and in vivo evaluation of different biopsy needles and devices for breast biopsy.

PubMed

Helbich, T H; Rudas, M; Böhm, G; Huber, S; Wagner, T; Taucher, S; Wolf, G; Mostbeck, G H

1999-01-01

In an experimental study (in vitro and in vivo) we evaluated the efficacy of various biopsy needles/devices for breast biopsy. In vitro, biopsies of five human cadaveric breast specimens were performed using 33 different needles/devices ranging from 14 to 20-gauge. Of these 33 needles/devices, 22 optimally performing needles were selected for the in vivo study. In the clinical part of the study, 44 breast lesions were randomly biopsied with each of the 22 needles/devices under stereotactic guidance. Tissue specimens were analysed quantitatively and qualitatively. Several automatic long-throw guns (Acecut, Asap, Biopty, Magnum) obtained greater tissue areas and had a better histopathologic score than the conventional type of a side-notch needle like Trucut, an aspiration needle like Surecut, or an end-cut needle like Autovac. The automatic long-throw guns performed better than the short-throw Monopty gun. Regardless of needle size (14-20-gauge), breast biopsies should be routinely performed with automated long-throw side-notch guns (Acecut, Asap, Biopty, Magnum).

Test report for 120-inch-diameter Solid Rocket Booster (SRB) model tests. [floating and towing characteristics of space shuttle boosters

NASA Technical Reports Server (NTRS)

Jones, W. C.

1973-01-01

The space shuttle solid rocket boosters (SRB's) will be jettisoned to impact in the ocean within a 200-mile radius of the launch site. Tests were conducted at Long Beach, California, using a 12-inch diameter Titan 3C model to simulate the full-scale characteristics of the prototype SRB during retrieval operations. The objectives of the towing tests were to investigate and assess the following: (1) a floating and towing characteristics of the SRB; (2) need for plugging the SRB nozzle prior to tow; (3) attach point locations on the SRB; (4) effects of varying the SRB configuration; (5) towing hardware; and (6) difficulty of attaching a tow line to the SRB in the open sea. The model was towed in various sea states using four different types and varying lengths of tow line at various speeds. Three attach point locations were tested. Test data was recorded on magnetic tape for the tow line loads and for model pitch, roll, and yaw characteristics and was reduced by computer to tabular printouts and X-Y plots. Profile and movie photography provided documentary test data.

[Research of Identify Spatial Object Using Spectrum Analysis Technique].

PubMed

Song, Wei; Feng, Shi-qi; Shi, Jing; Xu, Rong; Wang, Gong-chang; Li, Bin-yu; Liu, Yu; Li, Shuang; Cao Rui; Cai, Hong-xing; Zhang, Xi-he; Tan, Yong

2015-06-01

The high precision scattering spectrum of spatial fragment with the minimum brightness of 4.2 and the resolution of 0.5 nm has been observed using spectrum detection technology on the ground. The obvious differences for different types of objects are obtained by the normalizing and discrete rate analysis of the spectral data. Each of normalized multi-frame scattering spectral line shape for rocket debris is identical. However, that is different for lapsed satellites. The discrete rate of the single frame spectrum of normalized space debris for rocket debris ranges from 0.978% to 3.067%, and the difference of oscillation and average value is small. The discrete rate for lapsed satellites ranges from 3.118 4% to 19.472 7%, and the difference of oscillation and average value relatively large. The reason is that the composition of rocket debris is single, while that of the lapsed satellites is complex. Therefore, the spectrum detection technology on the ground can be used to the classification of the spatial fragment.

46 CFR 57.06-4 - Production testing specimen requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... WELDING AND BRAZING Production Tests § 57.06-4 Production testing specimen requirements. (a) For test... to welding shall not throw the finished test plate out of line by an angle of over 5°. (c) Where the welding has warped the test plates, the plates shall be straightened before being stress-relieved. The...

46 CFR 57.06-4 - Production testing specimen requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... WELDING AND BRAZING Production Tests § 57.06-4 Production testing specimen requirements. (a) For test... to welding shall not throw the finished test plate out of line by an angle of over 5°. (c) Where the welding has warped the test plates, the plates shall be straightened before being stress-relieved. The...

46 CFR 57.06-4 - Production testing specimen requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... WELDING AND BRAZING Production Tests § 57.06-4 Production testing specimen requirements. (a) For test... to welding shall not throw the finished test plate out of line by an angle of over 5°. (c) Where the welding has warped the test plates, the plates shall be straightened before being stress-relieved. The...

46 CFR 57.06-4 - Production testing specimen requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... WELDING AND BRAZING Production Tests § 57.06-4 Production testing specimen requirements. (a) For test... to welding shall not throw the finished test plate out of line by an angle of over 5°. (c) Where the welding has warped the test plates, the plates shall be straightened before being stress-relieved. The...

46 CFR 57.06-4 - Production testing specimen requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... WELDING AND BRAZING Production Tests § 57.06-4 Production testing specimen requirements. (a) For test... to welding shall not throw the finished test plate out of line by an angle of over 5°. (c) Where the welding has warped the test plates, the plates shall be straightened before being stress-relieved. The...

Differences in ball speed and three-dimensional kinematics between male and female handball players during a standing throw with run-up.

PubMed

Serrien, Ben; Clijsen, Ron; Blondeel, Jonathan; Goossens, Maggy; Baeyens, Jean-Pierre

2015-01-01

The purpose of this paper was to examine differences in ball release speed and throwing kinematics between male and female team-handball players in a standing throw with run-up. Other research has shown that this throwing type produces the highest ball release speeds and comparing groups with differences in ball release speed can suggest where this difference might come from. If throwing technique differs, perhaps gender-specific coordination- and strength-training guidelines are in order. Measurements of three-dimensional kinematics were performed with a seven-camera VICON motion capture system and subsequent joint angles and angular velocities calculations were executed in Mathcad. Data-analysis with Statistical Parametric Mapping allowed us to examine the entire time-series of every variable without having to reduce the data to certain scalar values such as minima/maxima extracted from the time-series. Statistical Parametric Mapping enabled us to detect several differences in the throwing kinematics (12 out of 20 variables had one or more differences somewhere during the motion). The results indicated two distinct strategies in generating and transferring momentum through the kinematic chain. Male team-handball players showed more activity in the transverse plane (pelvis and trunk rotation and shoulder horizontal abduction) whereas female team-handball players showed more activity in the sagital plane (trunk flexion). Also the arm cocking maneuver was quite different. The observed differences between male and female team handball players in the motions of pelvis, trunk and throwing arm can be important information for coaches to give feedback to athletes. Whether these differences contribute to the observed difference in ball release speed is at the present unclear and more research on the relation with anthropometric profile needs to be done. Kinematic differences might suggest gender-specific training guidelines in team-handball.

Development of Overarm Throwing Technique Reflects Throwing Ability during Childhood

PubMed Central

KASUYAMA, Tatsuya; MUTOU, Ikuo; SASAMOTO, Hitoshi

2016-01-01

Background: It is important to acquire fundamental movement skills during childhood. Throwing is a representative manipulative skill required for various intrinsic factors. However, the relationship between intrinsic factors and throwing ability in childhood is unclear. The purpose of this study was to investigate intrinsic factors related to the ball throwing distance of Japanese elementary school children. Methods: Japanese elementary school children from grades 1-6 (aged 6-12 years; n=112) participated in this study. The main outcome was throwing ability, which was measured as the ball throwing distance. We measured five general anthropometric parameters, seven physical fitness parameters, and the Roberton's developmental sequence for all subjects. The relationships between the throwing ability and the 13 parameters were analysed. Results: The Roberton's developmental sequence was the best predictor of ball throwing distance (r=0.80, p≤0.01). The best multiple regression model, which included sex, handgrip strength, shuttle run test, and the Roberton's developmental sequence, accounted for 81% of the total variance. Conclusions: The development of correct throwing technique reflects throwing abilities in childhood. In addition to the throwing sequence, enhancement of grip strength and aerobic capacity are also required for children's throwing ability. PMID:28289578

Performance and Kinematics of Various Throwing Techniques in Team-Handball

PubMed Central

Wagner, Herbert; Pfusterschmied, Jürgen; von Duvillard, Serge P.; Müller, Erich

2011-01-01

In team-handball competition, the players utilize various throwing techniques that differ in the lower body movements (with and without run-up or jump). These different lower body movements influence changes in the upper body movements and thus also affect the performance. A comprehensive analysis of 3D-kinematics of team-handball throws that may explain these differences in performance is lacking. Consequently, the purpose of this study was (1) to compare performance (ball velocity and throwing accuracy) between the jump throw, standing throw with and without run-up, and the pivot throw; (2) to calculate the influence of kinematic parameters to ball velocity; and (3) to determine if these four throwing techniques differ significantly in kinematics. Three-dimensional kinematic data (angles, angular velocities and their timing, ball velocity and velocity of the center of mass) of 14 elite team-handball players were measured using an 8 camera Vicon MX13 motion capture system (Vicon, Oxford, UK), at 250 Hz. Significant difference was found between the four throwing techniques for ball velocity (p < 0. 001), maximal velocity of the center of mass in goal-directed movement (p < 0.001), and 15 additional kinematic variables (p < 0.003). Ball velocity was significant impacted by the run-up and the pelvis and trunk movements. Depending on floor contact (standing vs. jump throws), elite players in the study used two different strategies (lead leg braces the body vs. opposed leg movements during flight) to accelerate the pelvis and trunk to yield differences in ball velocity. However, these players were able to utilize the throwing arm similarly in all four throwing techniques. Key points Elite team-handball players achieved the greatest ball velocity in the standing throw with run-up (100%), followed by the standing throw without run-up (93%), jump throw (92%) and pivot throw (85%). Depending on the floor contact (standing vs. jump throws) the elite players of the study used two different strategies (lead leg braces the body vs. opposed leg movements during flight) to accelerate the pelvis and trunk that caused differences in ball velocity. Elite team-handball players were able to utilize the throwing arm similarly in all four throwing techniques. PMID:24149298

Kinematic comparison of team handball throwing with two different arm positions.

PubMed

Wagner, Herbert; Buchecker, Michael; von Duvillard, Serge P; Müller, Erich

2010-12-01

The aims of the present study were: (1) to compare the differences in the ball release speed and throwing accuracy between the ABOVE and SIDE throw; (2) to analyze kinematic differences of these two throwing techniques; and (3) to give practical applications to team handball coaches and players. Ball release speed, throwing accuracy, and kinematics were measured via the Vicon MX 13 (Vicon Peak, Oxford, UK) from 12 male elite right-handed team handball players. Results of our study suggest that the two throwing techniques differ significantly (P < .0073) in the angles and/or angular velocities of the trunk (flexion, left tilt and rotation) and shoulder (flexion and abduction) of the throwing arm that result in a significantly different ball release speed (1.4 ± 0.8 m/s; P < .001) and that throwing accuracy was not significantly different. Our results indicated that the different position of the hand at ball release of the ABOVE and SIDE throws is primarily caused by different trunk flexion and tilt angles that lead to differences in ball release speed but not in throwing accuracy, and that the participants try to move their throwing arm similarly in both throwing techniques.

"White men can't jump." But can they throw? Social perception in European basketball.

PubMed

Furley, P; Dicks, M

2014-10-01

In the present article, we investigate the influence of sociocultural stereotypes on the impression formation of basketball players and coaches. In Experiment 1 (n = 32), participants were shown a picture of a black or white basketball player prior to observation of a point-light video of a player executing a basketball free throw. The participant was informed that the player depicted in the picture was executing the free throw. Results indicated that ethnicity of the target player significantly influenced participant evaluations, demonstrating specific stereotypes about black and white basketball players when evaluating performance. In Experiment 2 (n = 30), results derived from the Implicit Association Test indicated that black players are implicitly associated with athletic player attributes. The results are in line with social schema theory and demonstrate that - similar to findings that have been reported in the United States - a subpopulation of German basketball players and coaches hold specific stereotypes about the abilities of black and white basketball athletes. These stereotypes bias impression formation when coaches and players make assessments of basketball performance. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Air-Powered Rockets.

ERIC Educational Resources Information Center

Rodriguez, Charley; Raynovic, Jim

This document describes methods for designing and building two types of rockets--rockets from paper and rockets from bottles. Devices used for measuring the heights that the rockets obtain are also discussed. (KHR)

Bertrand's Paradox: A Physical Way out along the Lines of Buffon's Needle Throwing Experiment

ERIC Educational Resources Information Center

Di Porto, P.; Crosignani, B.; Ciattoni, A.; Liu, H. C.

2011-01-01

Bertrand's paradox (Bertrand 1889 "Calcul des Probabilites" (Paris: Gauthier-Villars)) can be considered as a cautionary memento, to practitioners and students of probability calculus alike, of the possible ambiguous meaning of the term "at random" when the sample space of events is continuous. It deals with the existence of different possible…

Narrative in a Nutshell: Sharing Hopes, Fears, and Dreams with Self-Advocates

ERIC Educational Resources Information Center

Roets, Griet; Goodley, Dan; Van Hove, Geert

2007-01-01

The grand narrative of modernism is a dominating story with profound sociopolitical implications in the lives of people with the label of intellectual disabilities. In this article, we throw light on the life stories and interpretive theories of self-advocates, which usually remain hidden between the story-lines of life. Professionals in the field…

Effects of Variable Resistance Using Chains on Bench Throw Performance in Trained Rugby Players.

PubMed

Godwin, Mark S; Fernandes, John F T; Twist, Craig

2018-04-01

Godwin, MS, Fernandes, JFT, and Twist, C. Effects of variable resistance using chains on bench throw performance in trained rugby players. J Strength Cond Res 32(4): 950-954, 2018-This study sought to determine the effects of variable resistance using chain resistance on bench throw performance. Eight male rugby union players (19.4 ± 2.3 years, 88.8 ± 6.0 kg, 1RM 105.6 ± 17.0 kg) were recruited from a national league team. In a randomized crossover design, participant's performed 3 bench throws at 45% one repetition maximum (1RM) at a constant load (no chains) or a variable load (30% 1RM constant load and 15% 1RM variable load; chains) with 7 days between conditions. For each repetition, the peak and mean velocity, peak power, peak acceleration, and time to peak velocity were recorded. Differences in peak and mean power were very likely trivial and unclear between the chain and no chain conditions, respectively. Possibly greater peak and likely greater mean bar velocity were accompanied by likely to most likely greater bar velocity between 50 and 400 ms from initiation of bench press in the chain condition compared with the no chain condition. Accordingly, bar acceleration was very likely greater in the chain condition compared with the no chain condition. In conclusion, these results show that the inclusion of chain resistance can acutely enhance several variables in the bench press throw and gives support to this type of training.

Hydrocarbon-Fueled Rocket Engine Plume Diagnostics: Analytical Developments and Experimental Results

NASA Technical Reports Server (NTRS)

Tejwani, Gopal D.; McVay, Gregory P.; Langford, Lester A.; St. Cyr, William W.

2006-01-01

A viewgraph presentation describing experimental results and analytical developments about plume diagnostics for hydrocarbon-fueled rocket engines is shown. The topics include: 1) SSC Plume Diagnostics Background; 2) Engine Health Monitoring Approach; 3) Rocket Plume Spectroscopy Simulation Code; 4) Spectral Simulation for 10 Atomic Species and for 11 Diatomic Molecular Electronic Bands; 5) "Best" Lines for Plume Diagnostics for Hydrocarbon-Fueled Rocket Engines; 6) Experimental Set Up for the Methane Thruster Test Program and Experimental Results; and 7) Summary and Recommendations.

Comparison of In-Season-Specific Resistance vs. A Regular Throwing Training Program on Throwing Velocity, Anthropometry, and Power Performance in Elite Handball Players.

PubMed

Hermassi, Souhail; van den Tillaar, Roland; Khlifa, Riadh; Chelly, Mohamed Souhaiel; Chamari, Karim

2015-08-01

The purpose of this study was to compare the effect of a specific resistance training program (throwing movement with a medicine ball) with that of regular training (throwing with regular balls) on ball velocity, anthropometry, maximal upper-body strength, and power. Thirty-four elite male team handball players (age: 18 ± 0.5 years, body mass: 80.6 ± 5.5 kg, height: 1.80 ± 5.1 m, body fat: 13.4 ± 0.6%) were randomly assigned to 1 of the 3 groups: control (n = 10), resistance training group (n = 12), or regular throwing training group (n = 12). Over the 8-week in season, the athletes performed 3 times per week according to an assigned training program alongside their normal team handball training. One repetition maximum (1RM) bench press and 1RM pullover scores assessed maximal arm strength. Anthropometry was assessed by body mass, fat percentage, and muscle volumes of upper body. Handball throwing velocity was measured by a standing throw, a throw with run, and a jump throw. Power was measured by measuring total distance thrown by a 3-kg medicine ball overhead throw. Throwing ball velocity, maximal strength, power, and muscle volume increases for the specific resistance training group after the 8 weeks of training, whereas only maximal strength, muscle volume and power and in the jump throw increases were found for the regular throwing training group. No significant changes for the control group were found. The current findings suggest that elite male handball players can improve ball velocity, anthropometrics, maximal upper-body strength, and power during the competition season by implementing a medicine ball throwing program.

Uniting of NuSTAR Spacecraft and Rocket

NASA Image and Video Library

2012-02-23

Inside an environmental enclosure at Vandenberg Air Force Base processing facility in California, solar panels line the sides of NASA Nuclear Spectroscopic Telescope Array NuSTAR, which was just joined to the Orbital Sciences Pegasus XL rocket.

Movement variability and skill level of various throwing techniques.

PubMed

Wagner, Herbert; Pfusterschmied, Jürgen; Klous, Miriam; von Duvillard, Serge P; Müller, Erich

2012-02-01

In team-handball, skilled athletes are able to adapt to different game situations that may lead to differences in movement variability. Whether movement variability affects the performance of a team-handball throw and is affected by different skill levels or throwing techniques has not yet been demonstrated. Consequently, the aims of the study were to determine differences in performance and movement variability for several throwing techniques in different phases of the throwing movement, and of different skill levels. Twenty-four team-handball players of different skill levels (n=8) performed 30 throws using various throwing techniques. Upper body kinematics was measured via an 8 camera Vicon motion capture system and movement variability was calculated. Results indicated an increase in movement variability in the distal joint movements during the acceleration phase. In addition, there was a decrease in movement variability in highly skilled and skilled players in the standing throw with run-up, which indicated an increase in the ball release speed, which was highest when using this throwing technique. We assert that team-handball players had the ability to compensate an increase in movement variability in the acceleration phase to throw accurately, and skilled players were able to control the movement, although movement variability decreased in the standing throw with run-up. Copyright © 2011 Elsevier B.V. All rights reserved.

Statistical Estimation of Some Irrational Numbers Using an Extension of Buffon's Needle Experiment

ERIC Educational Resources Information Center

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

2006-01-01

In the nineteenth century many people tried to seek a value for the most famous irrational number, [pi], by means of an experiment known as Buffon's needle, consisting of throwing randomly a needle onto a surface ruled with straight parallel lines. Here we propose to extend this experiment in order to evaluate other irrational numbers, such as…

Rocket Power Plants Based on Nitric Acid and their Specific Propulsive Weights

NASA Technical Reports Server (NTRS)

Zborowski, Helmut

1947-01-01

Two fields are reserved for the application of rocket power plants. The first field is determined by the fact that the rocket power plant is the only type of power plant that can produce thrust without dependence upon environment. For this field,the rocket is therefore the only possible power plant and the limit of what may be done is determined by the status of the technical development of these power plants at the given moment. The second field is that in which the rocket power plant proves itself the most suitable as a high-power drive in free competition with other types of power plants. The exposition will be devoted to the demarcation of this field and its division among the various types of rocket power plants.

Automatic Detection of Pitching and Throwing Events in Baseball With Inertial Measurement Sensors.

PubMed

Murray, Nick B; Black, Georgia M; Whiteley, Rod J; Gahan, Peter; Cole, Michael H; Utting, Andy; Gabbett, Tim J

2017-04-01

Throwing loads are known to be closely related to injury risk. However, for logistic reasons, typically only pitchers have their throws counted, and then only during innings. Accordingly, all other throws made are not counted, so estimates of throws made by players may be inaccurately recorded and underreported. A potential solution to this is the use of wearable microtechnology to automatically detect, quantify, and report pitch counts in baseball. This study investigated the accuracy of detection of baseball pitching and throwing in both practice and competition using a commercially available wearable microtechnology unit. Seventeen elite youth baseball players (mean ± SD age 16.5 ± 0.8 y, height 184.1 ± 5.5 cm, mass 78.3 ± 7.7 kg) participated in this study. Participants performed pitching, fielding, and throwing during practice and competition while wearing a microtechnology unit. Sensitivity and specificity of a pitching and throwing algorithm were determined by comparing automatic measures (ie, microtechnology unit) with direct measures (ie, manually recorded pitching counts). The pitching and throwing algorithm was sensitive during both practice (100%) and competition (100%). Specificity was poorer during both practice (79.8%) and competition (74.4%). These findings demonstrate that the microtechnology unit is sensitive to detect pitching and throwing events, but further development of the pitching algorithm is required to accurately and consistently quantify throwing loads using microtechnology.

Hybrid rockets - Combining the best of liquids and solids

NASA Technical Reports Server (NTRS)

Cook, Jerry R.; Goldberg, Ben E.; Estey, Paul N.; Wiley, Dan R.

1992-01-01

Hybrid rockets employing liquid oxidizer and solid fuel grain answers to cost, safety, reliability, and environmental impact concerns that have become as prominent as performance in recent years. The oxidizer-free grain has limited sensitivity to grain anomalies, such as bond-line separations, which can cause catastrophic failures in solid rocket motors. An account is presently given of the development effort associated with the AMROC commercial hybrid booster and component testing efforts at NASA-Marshall. These hybrid rockets can be fired, terminated, inspected, evaluated, and restarted for additional testing.

ARC-2009-ACD09-0144-122

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more. Building a rocket from scratch.

46 CFR 160.036-2 - Type.

Code of Federal Regulations, 2012 CFR

2012-10-01

... APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket-Propelled Parachute Red Flare Distress Signals § 160.036-2 Type. (a) Handheld rocket-propelled parachute red flare distress signals specified by this subpart... fired from the hand to provide a rocket-propelled parachute red flare distress signal. (b) [Reserved] ...

46 CFR 160.036-2 - Type.

Code of Federal Regulations, 2014 CFR

2014-10-01

... APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket-Propelled Parachute Red Flare Distress Signals § 160.036-2 Type. (a) Handheld rocket-propelled parachute red flare distress signals specified by this subpart... fired from the hand to provide a rocket-propelled parachute red flare distress signal. (b) [Reserved] ...

46 CFR 160.036-2 - Type.

Code of Federal Regulations, 2010 CFR

2010-10-01

... APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket-Propelled Parachute Red Flare Distress Signals § 160.036-2 Type. (a) Handheld rocket-propelled parachute red flare distress signals specified by this subpart... fired from the hand to provide a rocket-propelled parachute red flare distress signal. (b) [Reserved] ...

46 CFR 160.036-2 - Type.

Code of Federal Regulations, 2011 CFR

2011-10-01

... APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket-Propelled Parachute Red Flare Distress Signals § 160.036-2 Type. (a) Handheld rocket-propelled parachute red flare distress signals specified by this subpart... fired from the hand to provide a rocket-propelled parachute red flare distress signal. (b) [Reserved] ...

46 CFR 160.036-2 - Type.

Code of Federal Regulations, 2013 CFR

2013-10-01

... APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket-Propelled Parachute Red Flare Distress Signals § 160.036-2 Type. (a) Handheld rocket-propelled parachute red flare distress signals specified by this subpart... fired from the hand to provide a rocket-propelled parachute red flare distress signal. (b) [Reserved] ...

Serious play: A comparative study of engagement and learning in hobby practices

NASA Astrophysics Data System (ADS)

Azevedo, Flavio Saraiva

This dissertation is concerned with human behavior usually attributed to individual interests. As conceptualized in experimental and educational psychology, an individual interest refers to a particular relationship (called an interest relationship) between a person and a set of topically related activities. Interest relationships are self-motivated, long-term, and relatively stable, though they might change over time. As an example, a teenager's enduring and self-motivated involvement with model rocketry reflects her individual interest in the topic or domain of rocketry. As an alternative to this formulation, I develop a practice-centered theory of persistent engagement---or, simply, a theory of persistence---in free-choice, self-motivated practices. Taken together, self-motivated, long-term persistence in a free-choice practice refers exactly to the same set of phenomena that is the purview of psychological theories of individual interests. Hobbies are prototypic of free-choice, self-motivated, extended pursuit practices and therefore are the focal object of study of this dissertation. The centerpiece of the theory I put forward is the grounded theoretical concept of lines of practice. A line of practice is a distinctive, recurrent pattern of engagement in a person's continued pursuit of a hobby. To return to the example above, our rocketry buff might have three lines of practice in her hobby---one related to designing and flying unusual rockets, the other related to designing and flying high-powered rockets, and yet a third line concerned with designing and flying low-powered models. Any particular line of practice entails a set of closely interrelated activities. For instance, designing and flying high-powered rockets might entail visiting particular hobby stores, becoming a member of particular rocketry clubs, and engaging in construction work. Designing and flying unusual rockets, on the other hand, might entail some very different activities (e.g., continuously searching for unusual materials that can be transformed into rockets), as well as activities that cross line boundaries (e.g., construction work). The "essence" that runs through a set of closely related activities is what defines a line of practice. Such an "essence" is determined by two structural elements. The first element is the preferences that a hobbyist brings to bear on her practice. Preferences refer to psychological constructs such as goals, beliefs, values, and so forth. Our hypothetical subject's line of unusual rockets might reflect her need to fashion an identity as a competent practitioner and her love of design and construction. The second structural element refers to the conditions of practice impinging on the persons hobby. Conditions of practice include such things as the material infrastructure available to the practitioner (e.g., tools for working rocket parts), the immediate circumstances of the hobbyist's life (e.g., the person's socio-economic status and whether or not the person has easy access to practice sites), the rules of practice adopted by a hobby community (e.g., the maximum ceiling for rocket flights), the larger socio-cultural space in which the hobby exists (e.g., the availability of hobby stores), and so on. Each of these factors, and the many sub-factors included therein, may be seen to provide constraints and affordances for practice. I illustrate the theory with a comparative study of two hobby practices with techno-scientific underpinnings---model rocketry and amateur astronomy. The empirical base of the work is a series of ethnographic video records of two focal subjects, one for each hobby practice. (Abstract shortened by UMI.)

Kinetics of throwing arm joints and the trunk motion during an overarm distance throw by skilled Japanese elementary school boys.

PubMed

Kobayashi, Yasuto; Ae, Michiyoshi; Miyazaki, Akiyo; Fujii, Norihisa; Iiboshi, Akira; Nakatani, Hideki

2016-09-01

The purpose of this study was to investigate joint kinetics of the throwing arms and role of trunk motion in skilled elementary school boys during an overarm distance throw. Throwing motions of 42 boys from second, fourth, and sixth grade were videotaped with three high-speed cameras operating at 300 fps. Seven skilled boys from each grade were selected on the basis of throwing distance for three-dimensional kinetic analysis. Joint forces, torques, and torque powers of the throwing arm joints were calculated from reconstructed three-dimensional coordinate data smoothed at cut-off frequencies of 10.5-15 Hz and by the inverse dynamics method. Throwing distance and ball velocity significantly increased with school grade. The angular velocity of elbow extension before ball release increased with school grade, although no significant increase between the grades was observed in peak extension torque of elbow joint. The joint torque power of shoulder internal/external rotation tended to increase with school grade. When teaching the overarm throw, elementary school teachers should observe large backward twisting of trunk during the striding phase and should keep in mind that young children, such as second graders (age 8 years), will be unable to effectively utilise shoulder external/internal rotation during the throwing phase.

ARC-2009-ACD09-0144-126

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more. Launching the rocket you've built from scratch.

High-Pressure Burning Rate Studies of Solid Rocket Propellants

DTIC Science & Technology

2013-01-01

monopropellant burning rate. The self-de§agration rates of neat AP are plotted in Fig. 2 for both pressed pellets and single crystals. There is agreement...rate data from various investigators: 1 ¡ [2]; pressed pellets : 2 ¡ [3], 3 ¡ [4], and 4 ¡ [2]; and single crystals: 5 ¡ [5], and 6 ¡ [6]. Line ¡ AP...7]. Strand or window burners have had more use in the solid propellant community. There are numerous types and styles of combustion vessels, but they

Radiometric observations of the 752.033-GHz rotational absorption line of H2O from a laboratory jet. [simulation of rocket plumes

NASA Technical Reports Server (NTRS)

Dionne, G. F.; Fitzgerald, J. F.; Chang, T.-S.; Fetterman, H. R.; Litvak, M. M.

1980-01-01

With the aid of a high-resolution two-stage heterodyne radiometer, spectral absorption measurements of the 752.033 GHz line of water vapor were carried out, using a blackbody continuum as a background radiation source for investigating the absorptive properties of the H2O content of high altitude rocket plumes. To simulate this physical situation in a laboratory environment, a small steam jet was operated within a large high-vacuum chamber, with the H2O jet plume traversing the radiometer line of sight. The experiments verified that this rotational line is optically thick, with excitation temperatures below 100 K, in the downstream part of the plume, as predicted by theoretical modelling.

Comparison of three baseball-specific 6-week training programs on throwing velocity in high school baseball players.

PubMed

Escamilla, Rafael F; Ionno, Michele; deMahy, M Scott; Fleisig, Glenn S; Wilk, Kevin E; Yamashiro, Kyle; Mikla, Tony; Paulos, Lonnie; Andrews, James R

2012-07-01

Throwing velocity is an important baseball performance variable for baseball pitchers, because greater throwing velocity results in less time for hitters to make a decision to swing. Throwing velocity is also an important baseball performance variable for position players, because greater throwing velocity results in decreased time for a runner to advance to the next base. This study compared the effects of 3 baseball-specific 6-week training programs on maximum throwing velocity. Sixty-eight high school baseball players 14-17 years of age were randomly and equally divided into 3 training groups and a nontraining control group. The 3 training groups were the Throwers Ten (TT), Keiser Pneumatic (KP), and Plyometric (PLY). Each training group trained 3 d·wk(-1) for 6 weeks, which comprised approximately 5-10 minutes for warm-up, 45 minutes of resistance training, and 5-10 for cool-down. Throwing velocity was assessed before (pretest) and just after (posttest) the 6-week training program for all the subjects. A 2-factor repeated measures analysis of variance with post hoc paired t-tests was used to assess throwing velocity differences (p < 0.05). Compared with pretest throwing velocity values, posttest throwing velocity values were significantly greater in the TT group (1.7% increase), the KP group (1.2% increase), and the PLY group (2.0% increase) but not significantly different in the control group. These results demonstrate that all 3 training programs were effective in increasing throwing velocity in high school baseball players, but the results of this study did not demonstrate that 1 resistance training program was more effective than another resistance training program in increasing throwing velocity.

Gender Differences in Motor Skills of the Overarm Throw

PubMed Central

Gromeier, Michael; Koester, Dirk; Schack, Thomas

2017-01-01

In this cross-sectional study, the qualitative and quantitative throwing performance of male and female athletes (6 to 16 years of age) was analyzed. The goal of this study was to assess whether there were gender based qualitative and quantitative differences in throwing performance of young athletes, throughout three different age bands (childhood, pubescence, and adolescence). Furthermore, we explored whether all components of the throwing movement are equally affected by gender differences. Focus was placed on five essential components of action: trunk, forearm, humerus, stepping, and backswing. Therefore, children and adolescents (N = 96) were invited to throw three times from three different distances, while aiming at a target placed at shoulder height. The participants were aspiring athletes, competitive in the sport handball. For analyzing the quality of movement the component approach of Halverson and Roberton (1984) was used. The throwing accuracy was noted and used to evaluate the quantitative performance of the throwing movement. Throughout three different age bands, no statistically significant difference was found between genders in throwing accuracy, i.e., quantitative performance. Regarding the qualitative evaluation of the throwing movement, male and female athletes differed significantly. The component approach yielded higher scores for male than for female participants. As expected, with increasing age qualitative and quantitative performance of male and female athletes improved. These results suggest that there are gender-specific differences in qualitative throwing performance, but not necessarily in quantitative throwing performance. Exploration shows that differences in the qualitative throwing performance were seen in specific components of action. Male and female athletes demonstrated similar movement patterns in humerus and forearm actions, but differed in trunk, stepping, and backswing actions. PMID:28261142

VARIABLE-THROW CAM

DOEpatents

Godsil, E.C.; Robinson, E.Y.

1963-07-16

A variable-throw cam comprising inner and outer eccentric sleeves which are adjustably locked together is described. The cam throw is varied by unlocking the inner and outer sleeves, rotating the outer sleeve relative to the inner one until the desired throw is obtained, and locking the sleeves together again. The cam is useful in applications wherein a continuously-variable throw is required, e.g., ram-and-die pressing operations, cyclic fatigue testing of materials, etc. (AEC)

Main lines of scientific and technical research at the Soviet Jet Propulsion Research Institute (RNII), 1933 - 1942

NASA Technical Reports Server (NTRS)

Shchetinkov, Y. S.

1977-01-01

The rapid development of rocketry in the U.S.S.R. during the post-war years was due largely to pre-war activity; in particular, to investigations conducted in the Jet Propulsion Research Institute (RNII). The history of RNII commenced in 1933, resulting from the merger of two rocket research organizations. Previous research was continued in areas of solid-propellant rockets, jet-assisted take-off of aircraft, liquid propellant engines (generally with nitric acid as the oxidizer), liquid-propellant rockets (generally with oxgen as the oxidizer), ram jet engines, rockets with and without wings, and rocket planes. RNII research is described and summarized for the years 1933-1942.

Elastic energy storage in the shoulder and the evolution of high-speed throwing in Homo

PubMed Central

Roach, Neil T.; Venkadesan, Madhusudhan; Rainbow, Michael J.; Lieberman, Daniel E.

2013-01-01

Although some primates, including chimpanzees, throw objects occasionally1,2, only humans regularly throw projectiles with high speed and great accuracy. Darwin noted that humans’ unique throwing abilities, made possible when bipedalism emancipated the arms, enabled foragers to effectively hunt using projectiles3. However, there has been little consideration of the evolution of throwing in the years since Darwin made his observations, in part because of a lack of evidence on when, how, and why hominins evolved the ability to generate high-speed throws4-8. Here, we show using experimental studies of throwers that human throwing capabilities largely result from several derived anatomical features that enable elastic energy storage and release at the shoulder. These features first appear together approximately two million years ago in the species Homo erectus. Given archaeological evidence that suggests hunting activity intensified around this time9, we conclude that selection for throwing in order to hunt likely played an important role in the evolution of the human genus. PMID:23803849

Analysis of the influence of the milling machine throw-out plate surfacing and structure design on throwing material

NASA Astrophysics Data System (ADS)

Fang, Yuanbin; Sha, Hongwei; Yu, Yunmin; Chen, Bing

2018-03-01

Material composition, hardness and wear properties of the throw-out plate improved are analysed on a road milling machine. At the same time, analyse the tissue and performance of Fe based alloy named Fe60 cladding layer using the plasma surfacing method. And the original and improved throw-out plates are analysed throwing material effect by the dynamic analysis. Then the throw-out plate samples are verified. The results show that Fe60 powder is selected as surface strengthening material. By the improved structure, the hardness of the throw-out plate increases from 14.6HRC to 57.5HRC, and the wear resistance increases from 0.452g-1 to 16.393g-1. At the same time, it increases from 3263 to 3433 to fall into the collecting material number of milling machine. It provides important guidance for structure design and process design of the milling machine throw-out plate.

Throwing speed and accuracy in baseball and cricket players.

PubMed

Freeston, Jonathan; Rooney, Kieron

2014-06-01

Throwing speed and accuracy are both critical to sports performance but cannot be optimized simultaneously. This speed-accuracy trade-off (SATO) is evident across a number of throwing groups but remains poorly understood. The goal was to describe the SATO in baseball and cricket players and determine the speed that optimizes accuracy. 20 grade-level baseball and cricket players performed 10 throws at 80% and 100% of maximal throwing speed (MTS) toward a cricket stump. Baseball players then performed a further 10 throws at 70%, 80%, 90%, and 100% of MTS toward a circular target. Baseball players threw faster with greater accuracy than cricket players at both speeds. Both groups demonstrated a significant SATO as vertical error increased with increases in speed; the trade-off was worse for cricketers than baseball players. Accuracy was optimized at 70% of MTS for baseballers. Throwing athletes should decrease speed when accuracy is critical. Cricket players could adopt baseball-training practices to improve throwing performance.

6. "EXPERIMENTAL ROCKET ENGINE TEST STATION AT AFFTC." A low ...

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

6. "EXPERIMENTAL ROCKET ENGINE TEST STATION AT AFFTC." A low oblique aerial view of Test Area 1-115, looking south, showing Test Stand 1-3 at left, Instrumentation and Control building 8668 at center, and Test Stand 15 at right. The test area is under construction; no evidence of railroad line in photo. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Leuhman Ridge near Highways 58 & 395, Boron, Kern County, CA

The Kinetic Chain Revisited: New Concepts on Throwing Mechanics and Injury.

PubMed

Chu, Samuel K; Jayabalan, Prakash; Kibler, W Ben; Press, Joel

2016-03-01

The overhead throwing motion is a complex activity that is achieved through activation of the kinetic chain. The kinetic chain refers to the linkage of multiple segments of the body that allows for transfer of forces and motion. The lower extremities and core provide a base of support, generating energy that is transferred eventually through the throwing arm and hand, resulting in release of the ball. The kinetic chain requires optimal anatomy, physiology, and mechanics and is involved in all 6 phases of overhead throwing: windup, stride, arm cocking, acceleration, deceleration, and follow-through. Breaks or deficits in the kinetic chain can lead to injury or decreased performance. Through an understanding of the mechanics and pathomechanics seen in each phase of throwing, the clinician can better evaluate and screen for potential kinetic chain deficits in the overhead throwing athlete. The purpose of this article is to review the biomechanics of the overhead throwing motion, the role of the kinetic chain in throwing, and the clinical evaluation and management of abnormal throwing mechanics and related injuries. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

30 CFR 57.9308 - Switch throws.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Switch throws. 57.9308 Section 57.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9308 Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from...

30 CFR 57.9308 - Switch throws.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Switch throws. 57.9308 Section 57.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9308 Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from...

30 CFR 56.9308 - Switch throws.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Switch throws. 56.9308 Section 56.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from contact...

30 CFR 57.9308 - Switch throws.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Switch throws. 57.9308 Section 57.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9308 Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from...

30 CFR 57.9308 - Switch throws.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Switch throws. 57.9308 Section 57.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9308 Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from...

30 CFR 56.9308 - Switch throws.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Switch throws. 56.9308 Section 56.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from contact...

30 CFR 56.9308 - Switch throws.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Switch throws. 56.9308 Section 56.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from contact...

30 CFR 56.9308 - Switch throws.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Switch throws. 56.9308 Section 56.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from contact...

30 CFR 56.9308 - Switch throws.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Switch throws. 56.9308 Section 56.9308 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Switch throws. Switch throws shall be installed to provide clearance to protect switchmen from contact...

No Side-to-Side Difference in Humeral Retroversion in Baseball Players with Shoulder Disorders Using a True Three-Dimensional Measurement Technique: Validation and Comparison

PubMed Central

Saka, Masayuki; Yamauchi, Hiroki; Yoshioka, Toru; Hamada, Hidetoshi; Gamada, Kazuyoshi

2014-01-01

Objectives: Increased humeral retroversion in the throwing shoulder is considered to exist in many baseball players and is often considered as a cause of internal rotation deficit. However, retroversion angles using two-dimensional (2D) methods utilized in previous studies did not correlated with a true three-dimensional measurement technique (3D retroversion) in our study. The purposes of this study were to determine 1) if significant side-to-side differences in retroversion exist, and 2) the relationships between retroversion and glenohumeral range of motion (ROM) in baseball players with a shoulder disorder. Methods: Fourteen male baseball players (age: 21.4 ± 1.5 years; mean ± standard deviation) with a throwing shoulder disorder were enrolled, including 11 in the collegiate and 3 in the adult levels, comprising 5 pitchers and 9 position players. The mean age when the athletes had started playing baseball was 9.1 years (range, 6 to 10 years) and the mean playing experience was 12.1 years (range, 9 to 17 years). Patients with history of fracture or surgery in the shoulder or elbow were excluded. Outcome measurements included a 3D retroversion angle and glenohumeral ROM in bilateral shoulders. Patients underwent CT scan at 1.0 mm slice pitch for the bilateral humerus and geometric bone models were created. The 3D retroversion angle was defined as an angle between the projected humeral neck line (connecting the spherical center of the humeral head and the cylindrical axis of the humeral shaft) onto the horizontal plane and the flexion-extension axis of the distal humerus obtained by a cylinder-fitting method for the capitulum and trochlea (intratester reliability: ICC 0.98, standard error of measurement: 1.7º). The CT slices for the proximal and distal humerus were used to measure a 2D-CT retroversion angle using a reported convention. An indirect measurement of retroversion was performed using a bicipital grove-ulna angle by an ultrasound images dusing a reported convention. Glenohumeral ROM measurements included internal rotation (IR) and horizontal adduction (HAd) in the supine position with the scapula manually stabilized on the treatment table. Independent t tests were used to determine if significant side-to-side differences exist in retroversion and glenohumeral ROM. Pearson correlation coefficients were used to determine the association between retroversion and glenohumeral ROM in the throwing shoulders. Statistical analysis was performed with PASW Statistics 18 (SPSS, Inc, Chicago, IL). An alpha level of 0.05 was set a priori for statistical significance. Results: No significant difference was found in 3D retroversion between the throwing and non-throwing shoulders (P = .182). The throwing shoulders demonstrated decreased IR and HAd compared with the non-throwing shoulders (P < .001 and P = .002, respectively). There were no significant correlations between retroversion and glenohumeral ROM for the throwing shoulders (Table). The 2D-CT retroversion and bicipital grove-ulna angles were greater in the throwing shoulder (P = .007 and .009, respectively). Conclusion: Contradicted to the previous studies, no side-to-side difference in retroversion and no association between retroversion and glenohumeral ROM were observed in the baseball players with a shoulder disorder. We believe that deficit in shoulder IR and HAd may be attributed to soft tissue tightness. The results of the previous studies involving humeral retroversion should be reassessed.

Throwing, the Shoulder, and Human Evolution.

PubMed

Kuhn, John E

2016-01-01

Throwing with accuracy and speed is a skill unique to humans. Throwing has many advantages and the ability to throw has likely been promoted through natural selection in the evolution of humans. There are many unsolved questions regarding the anatomy of the human shoulder. The purpose of this article is to review many of these mysteries and propose that the answer to these questions can be understood if one views the shoulder as a joint that has evolved to throw.

Secondary Impacts on Structures on the Lunar Surface

NASA Technical Reports Server (NTRS)

Christiansen, Eric; Walker, James D.; Grosch, Donald J.

2010-01-01

The Altair Lunar Lander is being designed for the planned return to the Moon by 2020. Since it is hoped that lander components will be re-used by later missions, studies are underway to examine the exposure threat to the lander sitting on the Lunar surface for extended periods. These threats involve both direct strikes of meteoroids on the vehicle as well as strikes from Lunar regolith and rock thrown by nearby meteorite strikes. Currently, the lander design is comprised of up to 10 different types of pressure vessels. These vessels included the manned habitation module, fuel, cryogenic fuel and gas storage containers, and instrument bays. These pressure vessels have various wall designs, including various aluminum alloys, honeycomb, and carbon-fiber composite materials. For some of the vessels, shielding is being considered. This program involved the test and analysis of six pressure vessel designs, one of which included a Whipple bumper shield. In addition to the pressure vessel walls, all the pressure vessels are wrapped in multi-layer insulation (MLI). Two variants were tested without the MLI to better understand the role of the MLI in the impact performance. The tests of performed were to examine the secondary impacts on these structures as they rested on the Lunar surface. If a hypervelocity meteor were to strike the surface nearby, it would throw regolith and rock debris into the structure at a much lower velocity. Also, when the manned module departs for the return to Earth, its rocket engines throw up debris that can impact the remaining lander components and cause damage. Glass spheres were used as a stimulant for the regolith material. Impact tests were performed with a gas gun to find the V50 of various sized spheres striking the pressure vessels. The impacts were then modeled and a fast-running approximate model for the V50 data was developed. This model was for performing risk analysis to assist in the vessel design and in the identification of ideal long-term mission sites. This paper reviews the impact tests and analysis and modeling examining the impact threat to various components in the lander design.

Night Airglow Observations from Orbiting Spacecraft Compared with Measurements from Rockets.

PubMed

Koomen, M J; Gulledge, I S; Packer, D M; Tousey, R

1963-06-07

A luminous band around the night-time horizon, observed from orbiting capsules by J. H. Glenn and M. S. Carpenter, and identified as the horizon enhancement of the night airglow, is detected regularly in rocket-borne studies of night airglow. Values of luminance and dip angle of this band derived from Carpenter's observations agree remarkably well with values obtained from rocket data. The rocket results, however, do not support Carpenter's observation that the emission which he saw was largely the atomic oxygen line at 5577 A, but assign the principal luminosity to the green continuum.

Acute effect of stretching modalities and time-pressure on accuracy and consistency of throwing darts among 12- and 13-year-old schoolboys.

PubMed

Frikha, Mohamed; Chaâri, Nesrine; Derbel, Mohammad S; Elghoul, Yousri; Zinkovsky, Anatoly V; Chamari, Karim

2017-09-01

The present study addressed the lack of data on the effect of different types of stretching on selected measures of throwing accuracy. We hypothesized that the stretching procedures, within pre-exercise warm-up, could affect the accuracy and the consistency in throwing darts performances under different stress conditions. Eighteen right-handed schoolboys (13.1±0.4 years, 166±0.1 cm and 54.5±9 kg; mean±SD) completed the Darts Throwing Accuracy Test in free (FDT) and in time-pressure (TPDT) conditions, either after static (SS), dynamic (DS), ballistic (BS) or no-stretching (NS) protocols, on nonconsecutive days and in a counter-balanced randomized order. After performing 5 minutes of light standardized jogging and one of the three stretching protocols for 10 minutes, each participant completed the FDT and TPDT tests. Mean scores, missed darts and variability of scores, were recorded and analyzed using a two-way ANOVA with repeated measures. Heart rate (HR), ratings of perceived exertion (RPE) and the task difficulty perception (DP), were recorded through each experimental session. There was no effect of the stretching procedures on accuracy in FDT. However, in the TPDT condition, better performances were recorded after NS and SS compared to DS and BS. The accuracy performances decreased in TPDT by 9.6% after NS (P<0.01); 15.3% after DS (P<0.001) and 11.8% after BS (P<0.001); but not after SS (P<0.05). Static stretching helped reducing the adverse effects of time-pressure on darts throwing performance. Consequently, static exercises are recommended before practicing activities requiring both upper limbs speed and accuracy.

Effects of 6-week sling-based training of the external-rotator muscles on the shoulder profile in elite female high school handball players.

PubMed

Genevois, Cyril; Berthier, Philippe; Guidou, Vincent; Muller, Franck; Thiebault, Boris; Rogowski, Isabelle

2014-11-01

In women's handball, the large numbers of throws and passes make the shoulder region vulnerable to overuse injuries. Repetitive throwing motions generate imbalance between shoulder internal- and external-rotator muscles. It has not yet been established whether sling-based training can improve shoulder external-rotator muscle strength. This study investigated the effectiveness of a 6-wk strengthening program in improving shoulder functional profile in elite female high school handball players. Crossover study. National elite handball training center. 25 elite female high school handball players. The program, completed twice per week for 6 wk, included sling-based strengthening exercises using a suspension trainer for external rotation with scapular retraction and scapular retraction alone. Maximal shoulder external- and internal-rotation strength, shoulder external- and internal-rotation range of motion (ROM), and maximal throwing velocity were assessed preintervention and postintervention for dominant and nondominant sides. After sling training, external- and internal-rotation strength increased significantly for both sides (P ≤ .001, and P = .004, respectively), with the result that there was no significant change in external- and internal-rotation strength ratios for either the dominant or the nondominant shoulder. No significant differences were observed for external-rotation ROM, while internal-rotation ROM decreased moderately, in particular in the dominant shoulder (P = .005). Maximal throwing velocity remained constant for the dominant arm, whereas a significant increase was found for the nondominant arm (P = .017). This 6-wk strengthening program was effective in improving shoulder external-rotator muscle strength but resulted in a decrease in the ROM in shoulder internal rotation, while throwing velocity remained stable. Adding a stretching program to this type of sling-based training program might help avoid potential detrimental effects on shoulder ROM.

Performance and technical feasibility comparison of reusable launch systems: A synthesis of the ESA winged launcher studies

NASA Astrophysics Data System (ADS)

Berry, W.; Grallert, H.

1996-02-01

The paper presents a synthesis of the performance and technical feasibility assessment of 7 reusable launcher types, comprising 13 different vehicles, studied by European Industry for ESA in the ESA Winged Launcher Study in the period January 1988 to May 1994. The vehicles comprised single-stage-to-orbit (SSTO) and two-stage-to-orbit (TSTO) vehicles, propelled by either air-breathing/rocket propulsion or entirely by rocket propulsion. The results showed that an SSTO vehicle of the HOTOL-type, propelled by subsonic combustion air-breathing/rocket engines could barely deliver the specified payload mass and was aerodynamically unstable; that a TSTO vehicle of the Saenger type, employing subsonic combustion airbreathing propulsion in its first stage and rocket propulsion in its second stage, could readily deliver the specified payload mass and was found to be technically feasible and versatile; that an SSTO vehicle of the NASP type, propelled by supersonic combustion airbreathing/rocket propulsion was able to deliver a reduced payload mass, was very complex and required very advanced technologies; that an air-launched rocket propelled vehicle of the Interim HOTOL type, although technically feasible, could deliver only a reduced payload mass, being constrained by the lifting capability of the carrier airplane; that three different, entirely rocket-propelled vehicles could deliver the specified payload mass, were technically feasible but required relatively advanced technologies.

Effect of verbal instructions and image size on visual search strategies in basketball free throw shooting.

PubMed

Al-Abood, Saleh A; Bennett, Simon J; Hernandez, Francisco Moreno; Ashford, Derek; Davids, Keith

2002-03-01

We assessed the effects on basketball free throw performance of two types of verbal directions with an external attentional focus. Novices (n = 16) were pre-tested on free throw performance and assigned to two groups of similar ability (n = 8 in each). Both groups received verbal instructions with an external focus on either movement dynamics (movement form) or movement effects (e.g. ball trajectory relative to basket). The participants also observed a skilled model performing the task on either a small or large screen monitor, to ascertain the effects of visual presentation mode on task performance. After observation of six videotaped trials, all participants were given a post-test. Visual search patterns were monitored during observation and cross-referenced with performance on the pre- and post-test. Group effects were noted for verbal instructions and image size on visual search strategies and free throw performance. The 'movement effects' group saw a significant improvement in outcome scores between the pre-test and post-test. These results supported evidence that this group spent more viewing time on information outside the body than the 'movement dynamics' group. Image size affected both groups equally with more fixations of shorter duration when viewing the small screen. The results support the benefits of instructions when observing a model with an external focus on movement effects, not dynamics.

An Unexpected Effect: Restitution Maintains Object Throwing.

ERIC Educational Resources Information Center

Jensen, Mary

1988-01-01

This study examined effects of restitution on object throwing behavior of an adolescent male with severe mental retardation. Restitution was shown to maintain throwing behavior. When the subject was not forced to pick up what he threw (no restitution), throwing dropped to zero and was maintained at a very low rate. (Author/PB)

Throwing velocities, anthropometric characteristics, and efficacy indices of women's European water polo subchampions.

PubMed

Alcaraz, Pedro E; Abraldes, J Arturo; Ferragut, Carmen; Rodríguez, Nuria; Argudo, Francisco M; Vila, Helena

2011-11-01

Water polo is a team sport characterized by a high-intensity, intermittent activity, where technical and tactical aspect are of a great importance. For that reason, the main aim of this study was to define the anthropometrical characteristics, maximum isometric grip strength, training and competition throwing velocities, and the efficacy indices in female high-level water polo players. A second purpose was to examine the differences between the throwing velocities in training vs. European championships in the water polo female national team. Ten elite trained female water polo players participated in this study. Before the competitive phase of their season, the following measures were taken: standard anthropometry, static and dynamic training throwing velocities, and hand-grip dynamometry. In the competitive phase, efficacy indices, average and maximum throwing velocities from all the participants were also determined. Significant differences (p ≤ 0.05) were found between different training situations and different competitive throwing velocities. We concluded that elite female water polo players modify their throwing velocity depending if the throw is performed during training or competitive situation.

Effect of stride length on overarm throwing delivery: A linear momentum response.

PubMed

Ramsey, Dan K; Crotin, Ryan L; White, Scott

2014-12-01

Changing stride length during overhand throwing delivery is thought to alter total body and throwing arm linear momentums, thereby altering the proportion of throwing arm momentum relative to the total body. Using a randomized cross-over design, nineteen pitchers (15 collegiate and 4 high school) were assigned to pitch two simulated 80-pitch games at ±25% of their desired stride length. An 8-camera motion capture system (240Hz) integrated with two force plates (960Hz) and radar gun tracked each throw. Segmental linear momentums in each plane of motion were summed yielding throwing arm and total body momentums, from which compensation ratio's (relative contribution between the two) were derived. Pairwise comparisons at hallmark events and phases identified significantly different linear momentum profiles, in particular, anteriorly directed total body, throwing arm, and momentum compensation ratios (P⩽.05) as a result of manipulating stride length. Pitchers with shorter strides generated lower forward (anterior) momentum before stride foot contact, whereas greater upward and lateral momentum (toward third base) were evident during the acceleration phase. The evidence suggests insufficient total body momentum in the intended throwing direction may potentially influence performance (velocity and accuracy) and perhaps precipitate throwing arm injuries. Copyright © 2014 Elsevier B.V. All rights reserved.

Neuromuscular and technical abilities related to age in water-polo players.

PubMed

De Siati, Fabio; Laffaye, Guillaume; Gatta, Giorgio; Dello Iacono, Antonio; Ardigò, Luca Paolo; Padulo, Johnny

2016-08-01

Testing is one of the important tasks in any multi-step sport programme. In most ball games, coaches assess motor, physical and technical skills on a regular basis in early stages of talent identification in order to further athletes' development. The purpose of the study was to investigate anthropometric variables and vertical jump heights as a free throw effectiveness predictor in water-polo players of different age groups. Two hundred and thirty-six young (10-18 years) male water-polo players partitioned into three age groups underwent anthropometric variables' measures and squat- and countermovement-jump tests, and performed water-polo free throws. Anthropometric variables, vertical jump heights and throw speed - as a proxy for free throw effectiveness - resulted different over age groups. Particularly, throw speed changed from 9.28 to 13.70 m · s(-1) (+48%) from younger to older players. A multiple-regression model indicated that body height, squat-jump height and throw time together explain 52% of variance of throw speed. In conclusion, tall height, high lower limb power and throwing quickness appeared to be relevant determinants for effective free throws. Such indications can help coaches during talent identification and development processes, even by means of novel training strategies. Further research is needed over different maturity statuses.

Network Policy Languages: A Survey and a New Approach

DTIC Science & Technology

2000-08-01

go, throwing a community into economic chaos. These events could result from discontinued funding from Silicon Valley investors who became aware of...prevented. C. POLICY HIERARCHIES FOR DISTRIBUTED SYSTEMS MANAGEMENT In [23], Moffett and Sloman form a policy hierarchy is by refining general high...management behavior of a system, without coding the behavior into the manager agents. Lupu and Sloman focus on techniques and tool support for off-line

GLC_Exec v. 1.2.1

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

Kilgore, Roger Martin; Soloboda, Alexander Joseph

Launching a rocket involves a controlled transition of the rocket subsystems from a quiescent state to the launch state (i.e., lift-off). In order to launch safely, with confidence that the rocket will successfully complete its mission, the state-of-health for all rocket subsystems and critical ground support equipment must be closely monitored throughout the launch process. This is accomplished by the ground support engineers using mission-specific ground support equipment. A subset of the GSE, the Remote Electrical Ground Interface System (REGIS), is located nearest the rocket to which it's connected via the Umbilical, a wiring harness providing power, sensor, and controlmore » lines. The REGIS also connects via Ethernet to the Ground Launch Computer (GLC).« less

Encyclopedia: Satellites and Sounding Rockets, August 1959 - December 1969

NASA Technical Reports Server (NTRS)

1970-01-01

Major space missions utilizing satellites or sounding rockets managed by the NASA Goddard Space Flight Center between August 1959 and December 1969 were documented. The information was presented in the following form: (1) description of each satellite project where Goddard was responsible for the spacecraft or the successful launch or both, with data such as launch characteristics, objectives, etc.; (2) description of each Goddard sounding rocket project, with the following data: sounding rocket type, vehicle number, experimental affiliation, and type of experiment; (3) brief description of current sounding rockets and launch vehicles; (4) table of tracking and data acquisition stations. Summary tables are also provided.

Throwing Accuracy

ERIC Educational Resources Information Center

Cross, Rod

2018-01-01

A simple throwing task is described to illustrate various aspects of projectile motion. The task was to throw a tennis ball in a waste paper bin about 2 m away. Success depends on skill, but it also depends on the physics of the problem. If the ball is thrown underarm, then success depends primarily on the throw speed, which must be controlled to…

Throwing accuracy

NASA Astrophysics Data System (ADS)

Cross, Rod

2018-05-01

A simple throwing task is described to illustrate various aspects of projectile motion. The task was to throw a tennis ball in a waste paper bin about 2 m away. Success depends on skill, but it also depends on the physics of the problem. If the ball is thrown underarm, then success depends primarily on the throw speed, which must be controlled to within about 2%. The launch angle can be chosen within a wide range. If the ball is thrown overarm, then the launch angle is just as important as the throw speed.

Rocket spectrogram of a solar flare in the 10-100 A region

NASA Technical Reports Server (NTRS)

Acton, L. W.; Bruner, M. E.; Brown, W. A.; Fawcett, B. C.; Schweizer, W.; Speer, R. J.

1985-01-01

The soft (10-100 A) X-ray spectrum of an M-class solar flare was observed with a high-resolution (0.02 A) rocket-borne spectrograph on 1982 July 13. The spectrum samples an area of 600/sq arcsec on the sun, centered on or near the brightest X-ray feature of the flare. Several hundred emission lines characteristic of temperatures from about 0.5 to 7 x 10 to the 6th K have been photographically recorded. All but three of the stronger lines have been identified. It is argued that previous identification of the line at 17.62 A as iron Ly-alpha is incorrect. Spectral lines from nickel, iron, chromium, calcium, sulphur, silicon, aluminium, magnesium, neon, oxygen, nitrogen, and carbon are tabulated and discussed with extensive reference to earlier work. Absolute line intensities are given and the calibration of the telescope-spectrograph is discussed.

High-speed schlieren imaging of rocket exhaust plumes

NASA Astrophysics Data System (ADS)

Coultas-McKenney, Caralyn; Winter, Kyle; Hargather, Michael

2016-11-01

Experiments are conducted to examine the exhaust of a variety of rocket engines. The rocket engines are mounted in a schlieren system to allow high-speed imaging of the engine exhaust during startup, steady state, and shutdown. A variety of rocket engines are explored including a research-scale liquid rocket engine, consumer/amateur solid rocket motors, and water bottle rockets. Comparisons of the exhaust characteristics, thrust and cost for this range of rockets is presented. The variety of nozzle designs, target functions, and propellant type provides unique variations in the schlieren imaging.

Differential Expression and Pathway Analysis in Drug-Resistant Triple-Negative Breast Cancer Cell Lines Using RNASeq Analysis.

PubMed

Shaheen, Safa; Fawaz, Febin; Shah, Shaheen; Büsselberg, Dietrich

2018-06-19

Triple-negative breast cancer (TNBC) is among the most notorious types of breast cancer, the treatment of which does not give consistent results due to the absence of the three receptors (estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) as well as high amount of molecular variability. Drug resistance also contributes to treatment unresponsiveness. We studied differentially expressed genes, their biological roles, as well as pathways from RNA-Seq datasets of two different TNBC drug-resistant cell lines of Basal B subtype SUM159 and MDA-MB-231 treated with drugs JQ1 and Dexamethasone, respectively, to elucidate the mechanism of drug resistance. RNA sequencing(RNA-Seq) data analysis was done using edgeR which is an efficient program for determining the most significant Differentially Expressed Genes (DEGs), Gene Ontology (GO) terms, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. iPathway analysis was further used to obtain validated results using analysis that takes into consideration type, function, and interactions of genes in the pathway. The significant similarities and differences throw light into the molecular heterogeneity of TNBC, giving clues into the aspects that can be focused to overcome drug resistance. From this study, cytokine-cytokine receptor interaction pathway appeared to be a key factor in TNBC drug resistance.

ELF waves and ion resonances produced by an electron beam emitting rocket in the ionosphere

NASA Technical Reports Server (NTRS)

Winckler, J. R.; Abe, Y.; Erickson, K. N.

1986-01-01

Results are reported from the ECHO-6 electron-beam-injection experiment, performed in the auroral-zone ionosphere on March 30, 1983 using a sounding rocket equipped with two electron guns and a free-flying plasma-diagnostics instrument package. The data are presented in extensive graphs and diagrams and characterized in detail. Large ELF wave variations, superposed on the strong beam-sector-directed quasi-dc component, are observed in the 100-eV beam-induced plasma when the beam is injected in a transverse spiral, but not when it is injected upward parallel to the magnetic-field line. ELF activity is found to be suppressed whenever the rocket passed through field lines with auroral activity, suggesting that the waves are produced by the interaction of the beam potentials, plasma currents, and return currents neutralizing the accelerator payload.

Is hefting to perceive the affordance for throwing a smart perceptual mechanism?

PubMed

Zhu, Qin; Bingham, Geoffrey P

2008-08-01

G. P. Bingham, R. C. Schmidt, and L. D. Rosenblum (1989) found that, by hefting objects of different sizes and weights, people could choose the optimal weight in each size for throwing to a maximum distance. In Experiment 1, the authors replicated this result. G. P. Bingham et al. hypothesized that hefting is a smart mechanism that allows objects to be perceived in the context of throwing dynamics. This hypothesis entails 2 assumptions. First, hefting by hand is required for information about throwing by hand. The authors tested and confirmed this in Experiments 2 and 3. Second, optimal objects are determined by the dynamics of throwing. In Experiment 4, the authors tested this by measuring throwing release angles and using them with mean thrown distances from Experiment 1 and object sizes and weights to simulate projectile motion and recover release velocities. The results showed that only weight, not size, affects throwing. This failed to provide evidence supporting the particular smart mechanism hypothesis of G. P. Bingham et al. Because the affordance relation is determined in part by the dynamics of projectile motion, the results imply that the affordance is learned from knowledge of results of throwing.

The Acute Effects of Upper Extremity Stretching on Throwing Velocity in Baseball Throwers

PubMed Central

Melton, Jason; Delobel, Ashley; Puentedura, Emilio J.

2013-01-01

Purpose. To examine the effects of static and proprioceptive neuromuscular facilitation (PNF) stretching of the shoulder internal rotators on throwing velocity. Subjects. 27 male throwers (mean age = 25.1 years old, SD = 2.4) with adequate knowledge of demonstrable throwing mechanics. Study Design. Randomized crossover trial with repeated measures. Methods. Subjects warmed up, threw 10 pitches at their maximum velocity, were randomly assigned to 1 of 3 stretching protocols (static, PNF, or no stretch), and then repeated their 10 pitches. Velocities were recorded after each pitch and average and peak velocities were recorded after each session. Results. Data were analyzed using a 3 × 2 repeated measures ANOVA. No significant interaction between stretching and throwing velocity was observed. Main effects for time were not statistically significant. Main effects for the stretching groups were statistically significant. Discussion. Results suggest that stretching of the shoulder internal rotators did not significantly affect throwing velocity immediately after stretching. This may be due to the complexity of the throwing task. Conclusions. Stretching may be included in a thrower's warm-up without any effects on throwing velocity. Further research should be performed using a population with more throwing experience and skill. PMID:26464880

Three-dimensional scapular kinematics during the throwing motion.

PubMed

Meyer, Kristin E; Saether, Erin E; Soiney, Emily K; Shebeck, Meegan S; Paddock, Keith L; Ludewig, Paula M

2008-02-01

Proper scapular motion is crucial for normal shoulder mechanics. Scapular motion affects glenohumeral joint function during throwing, yet little is known about this dynamic activity. Asymptomatic subjects (10 male and 10 female), ages 21 to 45, were analyzed. Electromagnetic surface sensors on the sternum, acromion, and humerus were used to collect 3-D motion data during three trials of low-velocity throwing. Scapular angular position data were described or five predetermined events throughout the throw corresponding with classic descriptions of throwing phases, and trial-to-trial reliability was determined. ANOVA compared scapular angles across events. Subjects demonstrated good to excellent reliability between trials of the throw (ICC 0.74-0.98). The scapula demonstrated a pattern of external rotation, upward rotation (peak of approx. 40 degrees), and poster humeral horizontal abduction. During the arm acceleration phase, the scapula moved toward greater internal rotation and began anteriorly tilting. At maximum humeral internal rotation, the scapula ended in internal rotation (55 degrees), upward rotation (20 degrees), and anterior tilting (3 degrees). Significant differences in scapular position (p<0.05) were identified across the throwing motion. Scapular data identify events in the throwing motion in which throwers may be more susceptible to shoulder pathologies related to abnormal scapular kinematics.

Motion-plane dependency of the range of dart throw motion and the effects of tendon action due to finger extrinsic muscles during the motion.

PubMed

Mitsukane, Masahiro; Sekiya, Noboru; Kamono, Arinori; Nakabo, Tohru

2018-03-01

[Purpose] To clarify the motion-plane dependency of the range of dart throw motion and the effects of tendon action due to long finger flexors and extensors during the motion. [Subjects and Methods] Forty healthy subjects attended the experiment, and the active range of wrist motion in seven motion planes was measured with an originally designed apparatus. [Results] The reliability of the measurement was acceptable. The range of dart throw motion depended on the motion planes, with a maximum at around the motion plane of 45° from the sagittal plane (45° of pronation). The tendon action of long finger muscles was shown in dart throw motion except in 45° of pronation. [Conclusion] Motion-plane dependency of the range of dart throw motion exists in healthy subjects. The absence of tendon action due to finger extrinsic muscles in dart throw motion at 45° might be one of the causes of the advantage of dart throw motion.

Optimal strategies for throwing accurately

PubMed Central

2017-01-01

The accuracy of throwing in games and sports is governed by how errors in planning and initial conditions are propagated by the dynamics of the projectile. In the simplest setting, the projectile path is typically described by a deterministic parabolic trajectory which has the potential to amplify noisy launch conditions. By analysing how parabolic trajectories propagate errors, we show how to devise optimal strategies for a throwing task demanding accuracy. Our calculations explain observed speed–accuracy trade-offs, preferred throwing style of overarm versus underarm, and strategies for games such as dart throwing, despite having left out most biological complexities. As our criteria for optimal performance depend on the target location, shape and the level of uncertainty in planning, they also naturally suggest an iterative scheme to learn throwing strategies by trial and error. PMID:28484641

Optimal strategies for throwing accurately

NASA Astrophysics Data System (ADS)

Venkadesan, M.; Mahadevan, L.

2017-04-01

The accuracy of throwing in games and sports is governed by how errors in planning and initial conditions are propagated by the dynamics of the projectile. In the simplest setting, the projectile path is typically described by a deterministic parabolic trajectory which has the potential to amplify noisy launch conditions. By analysing how parabolic trajectories propagate errors, we show how to devise optimal strategies for a throwing task demanding accuracy. Our calculations explain observed speed-accuracy trade-offs, preferred throwing style of overarm versus underarm, and strategies for games such as dart throwing, despite having left out most biological complexities. As our criteria for optimal performance depend on the target location, shape and the level of uncertainty in planning, they also naturally suggest an iterative scheme to learn throwing strategies by trial and error.

Antileukemic Activity of Tillandsia recurvata and Some of its Cycloartanes

PubMed Central

LOWE, HENRY I.C.; TOYANG, NGEH J.; WATSON, CHARAH T.; AYEAH, KENNETH N.N.; BRYANT, JOSEPH

2015-01-01

Background Approximately 250,000 deaths were caused by leukemia globally in 2012 and about 40%-50% of all leukemia diagnoses end-up in death. Medicinal plants are a rich source for the discovery of new drugs against leukemia and other types of cancers. To this end, we subjected the Jamaican ball moss (Tillandsia recurvata) and its cycloartanes, as well as some analogs, to in vitro screening against a number of leukemia cell lines. The WST-1 anti-proliferation assay was used to determine the anticancer activity of ball moss and two cycloartanes isolated from ball moss and four of their analogs against four leukemia cell lines (HL-60, K562, MOLM-14, monoMac6). Ball moss crude methanolic extract showed activity with a 50% inhibition concentration (IC50) value of 3.028 μg/ml against the Molm-14 cell line but was ineffective against HL-60 cells. The six cycloartanes tested demonstrated varying activity against the four leukemia cancer cell lines with IC50 values ranging from 1.83 μM to 18.3 μM. Five out of the six cycloartanes demonstrated activity, while one was inactive against all four cell lines. The preliminary activity demonstrated by the Jamaican ball moss and its cycloartanes against selected leukemia cell lines continues to throw light on the broad anticancer activity of ball moss. Further studies to evaluate the efficacy of these molecules in other leukemia cell lines are required in order to validate the activity of these molecules, as well as to determine their mechanisms of action and ascertain the activity in vivo in order to establish efficacy and safety profiles. PMID:24982361

Antileukemic activity of Tillandsia recurvata and some of its cycloartanes.

PubMed

Lowe, Henry I C; Toyang, Ngeh J; Watson, Charah T; Ayeah, Kenneth N N; Bryant, Joseph

2014-07-01

Approximately 250,000 deaths were caused by leukemia globally in 2012 and about 40%-50% of all leukemia diagnoses end-up in death. Medicinal plants are a rich source for the discovery of new drugs against leukemia and other types of cancers. To this end, we subjected the Jamaican ball moss (Tillandsia recurvata) and its cycloartanes, as well as some analogs, to in vitro screening against a number of leukemia cell lines. The WST-1 anti-proliferation assay was used to determine the anticancer activity of ball moss and two cycloartanes isolated from ball moss and four of their analogs against four leukemia cell lines (HL-60, K562, MOLM-14, monoMac6). Ball moss crude methanolic extract showed activity with a 50% inhibition concentration (IC50) value of 3.028 μg/ml against the Molm-14 cell line but was ineffective against HL-60 cells. The six cycloartanes tested demonstrated varying activity against the four leukemia cancer cell lines with IC50 values ranging from 1.83 μM to 18.3 μM. Five out of the six cycloartanes demonstrated activity, while one was inactive against all four cell lines. The preliminary activity demonstrated by the Jamaican ball moss and its cycloartanes against selected leukemia cell lines continues to throw light on the broad anticancer activity of ball moss. Further studies to evaluate the efficacy of these molecules in other leukemia cell lines are required in order to validate the activity of these molecules, as well as to determine their mechanisms of action and ascertain the activity in vivo in order to establish efficacy and safety profiles. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

A comparison of the technique of the football quarterback pass between high school and university athletes.

PubMed

Toffan, Adam; Alexander, Marion J L; Peeler, Jason

2017-07-28

The purpose of the study was to compare the most effective joint movements, segment velocities and body positions to perform the fastest and most accurate pass of high school and university football quarterbacks. Secondary purposes were to develop a quarterback throwing test to assess skill level, to determine which kinematic variables were different between high school and university athletes as well as to determine which variables were significant predictors of quarterback throwing test performance. Ten high school and ten university athletes were filmed for the study, performing nine passes at a target and two passes for maximum distance. Thirty variables were measured using Dartfish Team Pro 4.5.2 video analysis system, and Microsoft Excel was used for statistical analysis. University athletes scored slightly higher than the high school athletes on the throwing test, however this result was not statistically significant. Correlation analysis and forward stepwise multiple regression analysis was performed on both the high school players and the university players in order to determine which variables were significant predictors of throwing test score. Ball velocity was determined to have the strongest predictive effect on throwing test score (r = 0.900) for the high school athletes, however, position of the back foot at release was also determined to be important (r = 0.661) for the university group. Several significant differences in throwing technique between groups were noted during the pass, however, body position at release showed the greatest differences between the two groups. High school players could benefit from more complete weight transfer and decreased throw time to increase throwing test score. University athletes could benefit from increased throw time and greater range of motion in external shoulder rotation and trunk rotation to increase their throwing test score. Coaches and practitioners will be able to use the findings of this research to help improve these and related throwing variables in their high school and university quarterbacks.

CLASP2: The Chromospheric LAyer Spectro-Polarimeter

NASA Astrophysics Data System (ADS)

Rachmeler, Laurel; E McKenzie, David; Ishikawa, Ryohko; Trujillo Bueno, Javier; Auchère, Frédéric; Kobayashi, Ken; Winebarger, Amy; Bethge, Christian; Kano, Ryouhei; Kubo, Masahito; Song, Donguk; Narukage, Noriyuki; Ishikawa, Shin-nosuke; De Pontieu, Bart; Carlsson, Mats; Yoshida, Masaki; Belluzzi, Luca; Stepan, Jiri; del Pino Alemná, Tanausú; Ballester, Ernest Alsina; Asensio Ramos, Andres

2017-08-01

We present the instrument, science case, and timeline of the CLASP2 sounding rocket mission. The successful CLASP (Chromospheric Lyman-Alpha Spectro-Polarimeter) sounding rocket flight in 2015 resulted in the first-ever linear polarization measurements of solar hydrogen Lyman-alpha line, which is sensitive to the Hanle effect and can be used to constrain the magnetic field and geometric complexity of the upper chromosphere. Ly-alpha is one of several upper chromospheric lines that contain magnetic information. In the spring of 2019, we will re-fly the modified CLASP telescope to measure the full Stokes profile of Mg II h & k near 280 nm. This set of lines is sensitive to the upper chromospheric magnetic field via both the Hanle and the Zeeman effects.

76 FR 70695 - Taking and Importing Marine Mammals: U.S. Navy Training in 12 Range Complexes and U.S. Air Force...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-15

... regarding the types and amounts of missile and rocket launches that the USAF conducts. DATES: Comments and... missiles and rockets that could be launched over the course of the 5-year rule and indicated that marine... flexibility in the types and amounts of missile and rocket launches that they conduct. NMFS now proposes to...

Ego depletion and attention regulation under pressure: is a temporary loss of self-control strength indeed related to impaired attention regulation?

PubMed

Englert, Chris; Zwemmer, Kris; Bertrams, Alex; Oudejans, Raôul R

2015-04-01

In the current study we investigated whether ego depletion negatively affects attention regulation under pressure in sports by assessing participants' dart throwing performance and accompanying gaze behavior. According to the strength model of self-control, the most important aspect of self-control is attention regulation. Because higher levels of state anxiety are associated with impaired attention regulation, we chose a mixed design with ego depletion (yes vs. no) as between-subjects and anxiety level (high vs. low) as within-subjects factor. Participants performed a perceptual-motor task requiring selective attention, namely, dart throwing. In line with our expectations, depleted participants in the high-anxiety condition performed worse and displayed a shorter final fixation on bull's eye, demonstrating that when one's self-control strength is depleted, attention regulation under pressure cannot be maintained. This is the first study that directly supports the general assumption that ego depletion is a major factor in influencing attention regulation under pressure.

Visual uncertainty influences the extent of an especial skill.

PubMed

Czyż, S H; Kwon, O-S; Marzec, J; Styrkowiec, P; Breslin, G

2015-12-01

An especial skill in basketball emerges through highly repetitive practice at the 15 ft free throw line. The extent of the role vision plays in the emergence of an especial skill is unknown. We examined the especial skills of ten skilled basketball players in normal and blurred vision conditions where participants wore corrective lenses. As such, we selectively manipulated visual information without affecting the participants' explicit knowledge that they were shooting free throws. We found that shot efficiency was significantly lower in blurred vision conditions as expected, and that the concave shape of shot proficiency function in normal vision conditions became approximately linear in blurred vision conditions. By applying a recently proposed generalization model of especial skills, we suggest that the linearity of shot proficiency function reflects the participants' lesser dependence on especial skill in blurred vision conditions. The findings further characterize the role of visual context in the emergence of an especial skill. Copyright © 2015 Elsevier B.V. All rights reserved.

Screen Cage Ion Plating (SCIP) and scratch testing of polycrystalline aluminum oxide

NASA Technical Reports Server (NTRS)

Spalvins, Talivaldis; Sliney, Harold E.; Deadmore, Daniel L.

1992-01-01

A screen cage ion plating (SCIP) technique was developed to apply silver films on electrically nonconducting aluminum oxide. It is shown that SCIP has remarkable throwing power; surfaces to be coated need not be in direct line of sight with the evaporation source. Scratch tests, employing a diamond stylus with a 200 micro m radius tip, were performed on uncoated and on silver coated alumina. Subsequent surface analysis show that a significant amount of silver remains on the scratched surfaces, even in areas where high stylus load produced severe crack patterns in the ceramic. Friction coefficients were lowered during the scratch tests on the coated alumina indicating that this modification of the ion planting process should be useful for applying lubricating films of soft metals to electrical insulating materials. The very good throwing power of SCIP also strongly suggests general applicability of this process in other areas of technology, e.g., electronics, in addition to tribology.

Transfer of motor and perceptual skills from basketball to darts

PubMed Central

Rienhoff, Rebecca; Hopwood, Melissa J.; Fischer, Lennart; Strauss, Bernd; Baker, Joseph; Schorer, Jörg

2013-01-01

The quiet eye is a perceptual skill associated with expertise and superior performance; however, little is known about the transfer of quiet eye across domains. We attempted to replicate previous skill-based differences in quiet eye and investigated whether transfer of motor and perceptual skills occurs between similar tasks. Throwing accuracy and quiet eye duration for skilled and less-skilled basketball players were examined in basketball free throw shooting and the transfer task of dart throwing. Skilled basketball players showed significantly higher throwing accuracy and longer quiet eye duration in the basketball free throw task compared to their less-skilled counterparts. Further, skilled basketball players showed positive transfer from basketball to dart throwing in accuracy but not in quiet eye duration. Our results raise interesting questions regarding the measurement of transfer between skills. PMID:24062703

Throwing enhances humeral shaft cortical bone properties in pre-pubertal baseball players: a 12-month longitudinal pilot study.

PubMed

Weatherholt, Alyssa M; Warden, Stuart J

2018-06-01

To explore throwing athletes as a prospective, within-subject controlled model for studying the response of the skeleton to exercise. Male pre-pubertal throwing athletes (n=12; age=10.3±0.6 yrs) had distal humerus cortical volumetric bone mineral density (Ct.vBMD), cortical bone mineral content (Ct.BMC), total area (Tt.Ar), cortical area (Ct.Ar), medullary area (Me.Ar), cortical thickness (Ct.Th) and polar moment of inertia (IP) assessed within their throwing (exercised) and nonthrowing (control) arms by peripheral quantitative computed tomography at baseline and 12 months. Throwing-to-nonthrowing arm percent differences (i.e. bilateral asymmetry) were compared over time. Over 12 months, the throwing arm gained 4.3% (95% Cl=1.1% to 7.5%), 2.9% (95% Cl=0.3% to 5.4%), 3.9% (95% Cl=0.7% to 7.0%), and 8.2% (95% Cl=2.0% to 6.8%) more Ct.BMC, Ct.Ar, Tt.Ar, and I P than the nonthrowing arm, respectively (all p<0.05). There was no significant effect of throwing on Ct.vBMD, Ct.Th and Me.Ar (all p=0.18-0.82). Throwing induced surface-specific cortical bone adaptation at the distal humeral diaphysis that contributed to a gain in estimated strength. These longitudinal pilot data support the utility of throwing athletes as a within-subject controlled model to explore factors influencing exercise-induced bone adaptation during the critical growing years.

Time-motion analysis of goalball players in attacks: differences of the player positions and the throwing techniques.

PubMed

Monezi, Lucas Antônio; Magalhães, Thiago Pinguelli; Morato, Márcio Pereira; Mercadante, Luciano Allegretti; Furtado, Otávio Luis Piva da Cunha; Misuta, Milton Shoiti

2018-03-26

In this study, we aimed to analyse goalball players time-motion variables (distance covered, time spent, maximum and average velocities) in official goalball match attacks, taking into account the attack phases (preparation and throwing), player position (centres and wings) and throwing techniques (frontal, spin and between the legs). A total of 365 attacks were assessed using a video based method (2D) through manual tracking using the Dvideo system. Inferential non-parametric statistics were applied for comparison of preparation vs. throwing phase, wings vs. centres and, among the throwing techniques, frontal, spin and between the legs. Significant differences were found between the attack preparation versus the throwing phase for all player time-motion variables: distance covered, time spent, maximum player velocity and average player velocity. Wing players performed most of the throws (85%) and covered longer distances than centres (1.65 vs 0.31 m). The between the legs and the spin throwing techniques presented greater values for most of the time-motion variables (distance covered, time spent and maximum player velocity) than did the frontal technique in both attack phases. These findings provide important information regarding players' movement patterns during goalball matches that can be used to plan more effective training.

Relationship between throwing velocity, muscle power, and bar velocity during bench press in elite handball players.

PubMed

Marques, Mario C; van den Tilaar, Roland; Vescovi, Jason D; Gonzalez-Badillo, Juan Jose

2007-12-01

The purpose of this study was to examine the relationship between ball-throwing velocity during a 3-step running throw and dynamic strength, power, and bar velocity during a concentric-only bench-press exercise in team-handball players. Fourteen elite senior male team-handball players volunteered to participate. Each volunteer had power and bar velocity measured during a concentric-only bench-press test with 26, 36, and 46 kg, as well as having 1-repetition-maximum (1-RMBP) strength determined. Ball-throwing velocity was evaluated with a standard 3-step running throw using a radar gun. Ball-throwing velocity was related to the absolute load lifted during the 1-RMBP (r = .637, P = .014), peak power using 36 kg (r = .586, P = .028) and 46 kg (r = .582, P = .029), and peak bar velocity using 26 kg (r = .563, P = .036) and 36 kg (r = .625, P = .017). The results indicate that throwing velocity of elite team-handball players is related to maximal dynamic strength, peak power, and peak bar velocity. Thus, a training regimen designed to improve ball-throwing velocity in elite male team-handball players should include exercises that are aimed at increasing both strength and power in the upper body.

MIDDLE NORTH Series Pre-DICE THROW I, II and DICE THROW Test Execution Report

DTIC Science & Technology

1978-04-01

THROW 1 1- 14 1-10 Site Layout, 5 -Ton Events, Pre-DICE THROW I 1-16 1-11 Test Bed Layout - Pre-DICE THROW I 1-17 1-12 Airblast Gages and Instrumentation...111- 14 0-15 List of Tables (Cont’d) Table Page 3-3 Stacking Data 111-19 -22 3-4 Charge Weights 111-23 3- 5 ANFO Charge Summiary 111-23 3-6 Power...described in Table 1-1 and in Figures 1- 5 and 1-6 (these were detonated on 30 April, 14 May and 31 May 1975). Figures 1-7 and 1-8 show photographs of the ANFO

SCORE - Sounding-rocket Coronagraphic Experiment

NASA Astrophysics Data System (ADS)

Fineschi, Silvano; Moses, Dan; Romoli, Marco

The Sounding-rocket Coronagraphic Experiment - SCORE - is a The Sounding-rocket Coronagraphic Experiment - SCORE - is a coronagraph for multi-wavelength imaging of the coronal Lyman-alpha lines, HeII 30.4 nm and HI 121.6 nm, and for the broad.band visible-light emission of the polarized K-corona. SCORE has flown successfully in 2009 acquiring the first images of the HeII line-emission from the extended corona. The simultaneous observation of the coronal Lyman-alpha HI 121.6 nm, has allowed the first determination of the absolute helium abundance in the extended corona. This presentation will describe the lesson learned from the first flight and will illustrate the preparations and the science perspectives for the second re-flight approved by NASA and scheduled for 2016. The SCORE optical design is flexible enough to be able to accommodate different experimental configurations with minor modifications. This presentation will describe one of such configurations that could include a polarimeter for the observation the expected Hanle effect in the coronal Lyman-alpha HI line. The linear polarization by resonance scattering of coronal permitted line-emission in the ultraviolet (UV) can be modified by magnetic fields through the Hanle effect. Thus, space-based UV spectro-polarimetry would provide an additional new tool for the diagnostics of coronal magnetism.

46 CFR 160.040-5 - Approval and production tests.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Rocket Type (and Equipment) § 160.040-5 Approval and production tests. (a) Approval tests. An independent... lot of rockets which fails the inspections and tests must not be represented as meeting this subpart... rockets at least once each year. The inspection must determine that the appliances and rockets are being...

46 CFR 160.040-5 - Approval and production tests.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Rocket Type (and Equipment) § 160.040-5 Approval and production tests. (a) Approval tests. An independent... lot of rockets which fails the inspections and tests must not be represented as meeting this subpart... rockets at least once each year. The inspection must determine that the appliances and rockets are being...

46 CFR 160.040-5 - Approval and production tests.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Rocket Type (and Equipment) § 160.040-5 Approval and production tests. (a) Approval tests. An independent... lot of rockets which fails the inspections and tests must not be represented as meeting this subpart... rockets at least once each year. The inspection must determine that the appliances and rockets are being...

46 CFR 160.040-5 - Approval and production tests.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Rocket Type (and Equipment) § 160.040-5 Approval and production tests. (a) Approval tests. An independent... lot of rockets which fails the inspections and tests must not be represented as meeting this subpart... rockets at least once each year. The inspection must determine that the appliances and rockets are being...

46 CFR 160.040-5 - Approval and production tests.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Rocket Type (and Equipment) § 160.040-5 Approval and production tests. (a) Approval tests. An independent... lot of rockets which fails the inspections and tests must not be represented as meeting this subpart... rockets at least once each year. The inspection must determine that the appliances and rockets are being...

78 FR 60763 - Clarification on Fireworks Policy Regarding Approvals or Certifications for Firework Series

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-02

... Fountain Cylindrical Fountain Illuminating Torch Mine and Shell Missile with Fin-type Rocket Roman Candle Sky Rocket/Bottle Rocket Toy Smoke Device Wire Sparkler/Dipped Sparkler Display Aerial Shell...

NASA Social

NASA Image and Video Library

2012-05-18

Models of various rockets line a table at a NASA Social, Friday, May 18, 2012, at Kennedy Space Center in Cape Canaveral, Fla. About 50 NASA Social followers attended an event as part of activities surrounding the launch of Space Exploration Technologies, or SpaceX, demonstration mission of the company's Falcon 9 rocket to the International Space Station. Photo Credit: (NASA/Paul E. Alers)

Increased efficiency of mammalian somatic cell hybrid production under microgravity conditions during ballistic rocket flight

NASA Technical Reports Server (NTRS)

Schnettler, R.; Gessner, P.; Zimmermann, U.; Neil, G. A.; Urnovitz, H. B.

1989-01-01

The electrofusion of hybridoma cell lines under short-duration microgravity during a flight of the TEXUS 18 Black Brand ballistic sounding rocket at Kiruna, Sweden is reported. The fusion partners, growth medium, cell fusion medium, cell fusion, cell viability in the fusion medium, and postfusion cell culture are described, and the rocket, cell fusion chamber, apparatus, and module are examined. The experimental timeline, the effects of fusion medium and incubation time on cell viability and hybrid yields, and the effect of microgravity on hybrid yields are considered.

69. Photograph of line drawing. ISOMETRIC VIEW OF 500,000 POUND ...

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

69. Photograph of line drawing. ISOMETRIC VIEW OF 500,000 POUND STATIC TEST FACILITY, NO DATE - White Sands Missile Range, V-2 Rocket Facilities, Near Headquarters Area, White Sands, Dona Ana County, NM

70. Photograph of line drawing. TOPOGRAPHIC SITE PLAN OF 500,000 ...

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

70. Photograph of line drawing. TOPOGRAPHIC SITE PLAN OF 500,000 POUND STATIC TEST FACILITY, APRIL 1947 - White Sands Missile Range, V-2 Rocket Facilities, Near Headquarters Area, White Sands, Dona Ana County, NM

72. Photograph of line drawing. SOUTH ELEVATION OF MOTOR CARRIAGE, ...

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

72. Photograph of line drawing. SOUTH ELEVATION OF MOTOR CARRIAGE, 500,000 POUND STATIC TEST FACILITY, NO DATE - White Sands Missile Range, V-2 Rocket Facilities, Near Headquarters Area, White Sands, Dona Ana County, NM

Structural design of an in-line bolted joint for the space shuttle solid rocket motor case segments

NASA Technical Reports Server (NTRS)

Dorsey, John T.; Stein, Peter A.; Bush, Harold G.

1987-01-01

Results of a structural design study of an in-line bolted joint concept which can be used to assemble Space Shuttle Solid Rocket Motor (SRM) case segments are presented. Numerous parametric studies are performed to characterize the in-line bolted joint behavior as major design variables are altered, with the primary objective always being to keep the inside of the joint (where the O-rings are located) closed during the SRM firing. The resulting design has 180 1-inch studs, an eccentricity of -0.5 inch, a flange thickness of 3/4 inch, a bearing plate thickness of 1/4 inch, and the studs are subjected to a preload which is 70% of ultimate. The mass penalty per case segment joint for the in-line design is 346 lbm more than the weight penalty for the proposed capture tang fix.

A comparison of peak power in the shoulder press and shoulder throw.

PubMed

Dalziel, W M; Neal, R J; Watts, M C

2002-09-01

The ability to generate peak power is central for performance in many sports. Currently two distinct resistance training methods are used to develop peak power, the heavy weight/slow velocity and light weight/fast velocity regimes. When using the light weight/fast velocity power training method it was proposed that peak power would be greater in a shoulder throw exercise compared with a normal shoulder press. Nine males performed three lifts in the shoulder press and shoulder throw at 30% and 40% of their one repetition maximum (1RM). These lifts were performed identically, except for the release of the bar in the throw condition. A potentiometer attached to the bar measured displacement and duration of the lifts. The time of bar release in the shoulder throw was determined with a pressure switch. ANOVA was used to examine statistically significant differences where the level of acceptance was set at p < 0.05. Peak power was found to be significantly greater in the shoulder throw at 30% of 1 RM condition [F, (1, 23) = 2.325 p < 0.051 and at 40% of 1 RM [F, (1, 23) = 2.905 p < 0.05] compared to values recorded for the respective shoulder presses. Peak power was also greater in the 30% of 1 RM shoulder throw (510 +/- 103W) than in the 40% of 1 RM shoulder press (471 +/- 96W). Peak power was produced significantly later in the shoulder throw versus the shoulder press. This differing power reflected a greater bar velocity of the shoulder throw at both assigned weights compared with the shoulder press.

Performance enhancement among adolescent players after 10 weeks of pitching training with appropriate baseball weights.

PubMed

Yang, Wen-Wen; Liu, Ya-Chen; Lu, Lee-Chang; Chang, Hsiao-Yun; Chou, Paul Pei-Hsi; Liu, Chiang

2013-12-01

Compared with regulation-weight baseballs, lightweight baseballs generate lower torque on the shoulder and elbow joints without altering the pitching movement and timing. This study investigates the throwing accuracy, throwing velocity, arm swing velocity, and maximum shoulder external rotation (MSER) of adolescent players after 10 weeks of pitching training with appropriate lightweight baseballs. We assigned 24 adolescent players to a lightweight baseball group (group L) and a regulation-weight baseball group (group R) based on their pretraining throwing velocity. Both groups received pitching training 3 times per week for 10 weeks with 4.4- and 5-oz baseballs. The players' throwing accuracy, throwing velocity, arm swing velocity, and MSER were measured from 10 maximum efforts throws using a regulation-weight baseball before and after undergoing the pitching training. The results showed that the players in group L significantly increased their throwing velocity and arm swing velocity (p < 0.05) after 10 weeks of pitching training with the 4.4-oz baseball, whereas group R did not (p > 0.05). Furthermore, the percentage change in the throwing velocity and arm swing velocity of group L was significantly superior to that of group R (p < 0.05). Thus, we concluded that the 10 weeks of pitching training with an appropriate lightweight baseball substantially enhanced the arm swing velocity and throwing velocity of the adolescent baseball players. These findings suggest that using a lightweight baseball, which can reduce the risk of injury without altering pitching patterns, has positive training effects on players in the rapid physical growth and technique development stage.

A rocket-borne energy spectrometer using multiple solid-state detectors for particle identification

NASA Technical Reports Server (NTRS)

Fries, K. L.; Smith, L. G.; Voss, H. D.

1979-01-01

A rocket-borne experiment using energy spectrometers that allows particle identification by the use of multiple solid-state detectors is described. The instrumentation provides information regarding the energy spectrum, pitch-angle distribution, and the type of energetic particles present in the ionosphere. Particle identification was accomplished by considering detector loss mechanisms and their effects on various types of particles. Solid state detectors with gold and aluminum surfaces of several thicknesses were used. The ratios of measured energies for the various detectors were compared against known relationships during ground-based analysis. Pitch-angle information was obtained by using detectors with small geometrical factors mounted with several look angles. Particle flux was recorded as a function of rocket azimuth angle. By considering the rocket azimuth, the rocket precession, and the location of the detectors on the rocket, the pitched angle of the incident particles was derived.

Arm pain in youth baseball players: a survey of healthy players.

PubMed

Makhni, Eric C; Morrow, Zachary S; Luchetti, Timothy J; Mishra-Kalyani, Pallavi S; Gualtieri, Anthony P; Lee, Randall W; Ahmad, Christopher S

2015-01-01

Overuse injury in youth baseball players is increasing in prevalence, and these injuries have been correlated to pitching mechanics and pitch counts/types. Prior studies regarding arm pain in these athletes have focused simply on presence or absence of pain during the season rather than on detailed factors related to arm pain with respect to frequency, severity, and associated performance and psychosocial effect. The goal of this study was to investigate frequency, quality, and effect of arm pain in healthy youth baseball players. The hypothesis was that arm pain will affect a majority of healthy baseball players and will be associated with adverse psychosocial effects. Descriptive epidemiological study. A novel survey focusing on arm pain in youth baseball players was developed for the purpose of this study. Survey questions were formulated by a consortium of trainers, clinicians, and coaches. Surveys were administered to healthy youth baseball players throughout the states of New Jersey and New York. A total of 203 healthy players completed the survey; 23% of players (n=47) reported a prior overuse injury. Only 26% and 20% of players reported that their arm never hurt when throwing or the day after throwing, respectively; 30% of players reported that arm pain at least sometimes caused them to have less fun playing; and 46% of players reported at least once being encouraged to keep playing despite having arm pain. Pitchers were more likely to report arm pain while throwing and the day after throwing and to indicate that arm pain held them back from being a better player (all P<.05). Those with prior overuse injury were more likely to have arm pain while throwing, to have arm fatigue during a game or practice, and to be encouraged to keep playing despite having pain (all P<.05). A majority of healthy (actively competing) youth baseball players report at least some baseline arm pain and fatigue, and many players suffer adverse psychosocial effects from this pain. © 2014 The Author(s).

Dual-gate GaAs FET switches

NASA Astrophysics Data System (ADS)

Vorhaus, J. L.; Fabian, W.; Ng, P. B.; Tajima, Y.

1981-02-01

A set of multi-pole, multi-throw switch devices consisting of dual-gate GaAs FET's is described. Included are single-pole, single-throw (SPST), double-pole, double-throw (DPDT), and single-pole four-throw (SP4T) switches. Device fabrication and measurement techniques are discussed. The device models for these switches were based on an equivalent circuit of a dual-gate FET. The devices were found to have substantial gain in X-band and low Ku-band.

Reliability and validity of a talent identification test battery for seated and standing Paralympic throws.

PubMed

Spathis, Jemima Grace; Connick, Mark James; Beckman, Emma Maree; Newcombe, Peter Anthony; Tweedy, Sean Michael

2015-01-01

Paralympic throwing events for athletes with physical impairments comprise seated and standing javelin, shot put, discus and seated club throwing. Identification of talented throwers would enable prediction of future success and promote participation; however, a valid and reliable talent identification battery for Paralympic throwing has not been reported. This study evaluates the reliability and validity of a talent identification battery for Paralympic throws. Participants were non-disabled so that impairment would not confound analyses, and results would provide an indication of normative performance. Twenty-eight non-disabled participants (13 M; 15 F) aged 23.6 years (±5.44) performed five kinematically distinct criterion throws (three seated, two standing) and nine talent identification tests (three anthropometric, six motor); 23 were tested a second time to evaluate test-retest reliability. Talent identification test-retest reliability was evaluated using Intra-class Correlation Coefficient (ICC) and Bland-Altman plots (Limits of Agreement). Spearman's correlation assessed strength of association between criterion throws and talent identification tests. Reliability was generally acceptable (mean ICC = 0.89), but two seated talent identification tests require more extensive familiarisation. Correlation strength (mean rs = 0.76) indicated that the talent identification tests can be used to validly identify individuals with competitively advantageous attributes for each of the five kinematically distinct throwing activities. Results facilitate further research in this understudied area.

THORACOLUMBAR RANGE OF MOTION IN BASEBALL PITCHERS AND POSITION PLAYERS

PubMed Central

Lynall, Robert; Williams, Jeffrey G.; Wong, Regan; Onuki, Takashi; Meister, Keith

2013-01-01

Introduction/Background: Optimal baseball throwing mechanics require a significant contribution of thoracolumbar motion, particularly in the sagittal and transverse planes. This motion is key for proper transmission of forces from the lower to upper extremity, thereby minimizing a throwing athlete's risk of injury and maximizing athletic performance. Purpose: To define the active‐assisted thoracolumbar ROM of both baseball pitchers and position players and to compare these motions both within and between groups. Methods: Fifty‐six asymptomatic, collegiate and minor league baseball pitchers and 42 position players volunteered to participate. Active‐assisted thoracolumbar flexion, extension, and bilateral rotation ROM, were measured in a standing position, using two bubble inclinometers. Two‐tailed t tests were used to determine differences in ROM between and within the pitchers and position players. Results: The pitchers had significantly more rotation to the non‐throwing arm side as compared to the position players (p = .007, effect size = .61). The pitchers also had more rotation to the non‐throwing arm side as compared to their throwing side (p = .006, effect size = .47). There were no other significant differences between the pitchers and the position players (p > .53). Furthermore, the position players did not have a side‐to‐side rotation difference (p = .99). Conclusions: Pitchers have a greater amount of rotation ROM towards the non‐throwing arm side as compared to position players. Pitchers also have a greater amount of rotation ROM to the non‐throwing arm side as compared to their throwing side rotation. Because pitchers often present with posterior shoulder tightness and subsequent altered shoulder horizontal adduction and internal rotation ROM, the increase in non‐throwing side rotation ROM may occur in response to these adaptations. More specifically, this increase in non‐throwing side trunk rotation ROM may allow such athletes to bring the arm across the body during the follow‐through phase of the throwing motion despite posterior shoulder tightness. However, future research is necessary to investigate this relationship. Based on these results, clinicians should consider these thoracolumbar ROM adaptations in the prevention, evaluation, and treatment of baseball players. Level of Evidence: 2b PMID:24377063

Users manual for program NYQUIST: Liquid rocket nyquist plots developed for use on a PC computer

NASA Astrophysics Data System (ADS)

Armstrong, Wilbur C.

1992-06-01

The piping in a liquid rocket can assume complex configurations due to multiple tanks, multiple engines, and structures that must be piped around. The capability to handle some of these complex configurations have been incorporated into the NYQUIST code. The capability to modify the input on line has been implemented. The configurations allowed include multiple tanks, multiple engines, and the splitting of a pipe into unequal segments going to different (or the same) engines. This program will handle the following type elements: straight pipes, bends, inline accumulators, tuned stub accumulators, Helmholtz resonators, parallel resonators, pumps, split pipes, multiple tanks, and multiple engines. The code is too large to compile as one program using Microsoft FORTRAN 5; therefore, the code was broken into two segments: NYQUIST1.FOR and NYQUIST2.FOR. These are compiled separately and then linked together. The final run code is not too large (approximately equals 344,000 bytes).

Users manual for program NYQUIST: Liquid rocket nyquist plots developed for use on a PC computer

NASA Technical Reports Server (NTRS)

Armstrong, Wilbur C.

1992-01-01

The piping in a liquid rocket can assume complex configurations due to multiple tanks, multiple engines, and structures that must be piped around. The capability to handle some of these complex configurations have been incorporated into the NYQUIST code. The capability to modify the input on line has been implemented. The configurations allowed include multiple tanks, multiple engines, and the splitting of a pipe into unequal segments going to different (or the same) engines. This program will handle the following type elements: straight pipes, bends, inline accumulators, tuned stub accumulators, Helmholtz resonators, parallel resonators, pumps, split pipes, multiple tanks, and multiple engines. The code is too large to compile as one program using Microsoft FORTRAN 5; therefore, the code was broken into two segments: NYQUIST1.FOR and NYQUIST2.FOR. These are compiled separately and then linked together. The final run code is not too large (approximately equals 344,000 bytes).

Sensitivity of the curve-to-growth technique utilized in rocket experiments to determine the line shape of solar He I resonance lines

NASA Technical Reports Server (NTRS)

Wu, C. Y. R.; Ogawa, H. S.

1986-01-01

The sensitivity of the curve-of-growth (COG) technique utilized in rocket measurements to determine the line profiles of the solar He I resonance emissions is theoretically examined with attention to the possibility of determining the line core shape using this technique. The line at 584.334 A is chosen as an illustration. Various possible source functions of the solar line have been assumed in the computation of the integrated transmitted intensity. A recent observational data set obtained by the present researchers is used as the constraint of the computation. It is confirmed that the COG technique can indeed provide a good measurement of the solar line width. However, to obtain detailed knowledge of the solar profile at line center and in the core region, (1) it is necessary to be able to carry out relative solar flux measurements with a 1-percent or better precision, and (2) it must be possible to measure the He gas pressure in the absorption cell to lower than 0.1 mtorr. While these numbers apply specifically to the present geometry, the results are readily scaled to other COG measurements using other experimental parameters.

Berkeley extreme-ultraviolet airglow rocket spectrometer - BEARS

NASA Technical Reports Server (NTRS)

Cotton, D. M.; Chakrabarti, S.

1992-01-01

The Berkeley EUV airglow rocket spectrometer (BEARS) instrument is described. The instrument was designed in particular to measure the dominant lines of atomic oxygen in the FUV and EUV dayglow at 1356, 1304, 1027, and 989 A, which is the ultimate source of airglow emissions. The optical and mechanical design of the instrument, the detector, electronics, calibration, flight operations, and results are examined.

Field aligned currents and the auroral spectrum below 1 keV

NASA Technical Reports Server (NTRS)

Arnoldy, R. L.

1973-01-01

Measurements during auroral events were conducted with the aid of detectors flown aboard three Nike-Tomahawk rocket flights. The detectors used to measure the auroral spectrum below 1 keV consisted of electrostatic analyzers positioned in the rocket to measure particles moving up and down the magnetic field lines. The analyzers measured electrons and protons simultaneously during a given sweep.

Strength and Power Correlates of Throwing Velocity on Subelite Male Cricket Players.

PubMed

Freeston, Jonathan L; Carter, Thomas; Whitaker, Gary; Nicholls, Owen; Rooney, Kieron B

2016-06-01

Throwing velocity is an important aspect of fielding in cricket to affect run-outs and reduce the opponent's run-scoring opportunities. Although a relationship between strength and/or power and throwing velocity has been well established in baseball, water polo, and European handball, it has not been adequately explored in cricket. Consequently, this study aimed to determine the relationship between measures of strength and/or power and throwing velocity in cricket players. Seventeen male cricket players (mean ± SD; age, 21.1 ± 1.6 years; height, 1.79 ± 0.06 m; weight, 79.8 ± 6.4 kg) from an elite athlete program were tested for maximal throwing velocity from the stretch position and after a 3-meter shuffle. They were also assessed for strength and power using a range of different measures. Throwing velocity from the stretch position (30.5 ± 2.4 m·s) was significantly related to dominant leg lateral-to-medial jump (LMJ) distance (r = 0.71; p < 0.01), dominant shoulder internal rotation (IR) strength (r = 0.55; p ≤ 0.05), and dominant (r = 0.73; p < 0.01) and nondominant (r = 0.54; p ≤ 0.05) medicine ball rotation (MB Rot) throw velocity and medicine ball chest pass (MB CP) distance (r = 0.67; p < 0.01). A nonsignificant trend was observed for vertical jump (VJ) height (p = 0.06), whereas no significant relationships were observed for nondominant LMJ distance (p = 0.97), nondominant shoulder IR strength (p = 0.80), 1 repetition maximum (RM) squat strength (p = 0.57), 1RM bench press strength (p = 0.90), height (p = 0.33), or weight (p = 0.29). Multiple regression analysis revealed that dominant MB Rot and MB CP explained 66% of the variance. The results were similar for velocity after a shuffle step (31.8 ± 2.1 m·s); however, VJ height reached statistical significance (r = 0.51; p ≤ 0.05). The multiple regression was also similar with MB Rot and MB CP explaining 70% of the variance. The cricketers in this study threw with greater velocity than elite junior and subelite senior cricketers but with lower velocities than elite senior cricketers and collegiate level and professional baseball players. This is the first study to demonstrate a link between strength and/or power and throwing velocity in cricket players and highlight the importance of power development as it relates to throwing velocity. Exercises that more closely simulated the speed (body weight jumps and medicine ball throws) or movement pattern (shoulder IR) of overhead throwing were greater predictors of throwing velocity. Strength and conditioning staff should assess and develop power to enhance throwing performance in cricket players. Exercises with greater movement and speed specificity to throwing should be used in preference over exercises that are slower and have less movement specificity to the throwing motion. Cricket players should engage in power training to bridge the gap in performance between them and baseball players.

Medial elbow injury in young throwing athletes

PubMed Central

Gregory, Bonnie; Nyland, John

2013-01-01

Summary This report reviews the anatomy, overhead throwing biomechanics, injury mechanism and incidence, physical examination and diagnosis, diagnostic imaging and conservative treatment of medial elbow injuries in young throwing athletes. Based on the information a clinical management decision-making algorithm is presented. PMID:23888291

On-Line Course Development: Engaging and Retaining Students

ERIC Educational Resources Information Center

Bruster, Benita G.

2015-01-01

As the number of on-line classes and the demand for on-line education continues to sky-rocket, it is critical that course developers and university faculty have the skills to effectively design curricula, to develop engaging learning opportunities, and to create responsive courses that meet individual student needs. This paper details three…

Return to Throwing after Shoulder or Elbow Injury.

PubMed

Sgroi, Terrance A; Zajac, John M

2018-03-01

Throwing places high demands on the human body, and specific characteristics are developed over time unique to these athletes. When returning to throw after injury, it is important to follow a criterion-based progression that allows the body to be prepared appropriately for the stresses that throwing will require. There is currently a void in the literature for criteria-based progression that helps these athletes return to the highest level of play. As injury rates continue to rise in baseball, there is increased evidence showing contributions of the core and lower extremity to the baseball pitch. There is also additional data showing pitcher specific characteristics such as range of motion and scapular position in this unique population. The rehab professional should take into account every phase of the pitch starting from balance through ball release when designing a comprehensive return-to-throwing program. Returning an athlete back to a throwing sport can be an overwhelming task. The rehabilitation specialist must have a sound understanding of the throwing motion as well as any biomechanical implications on the body, contributions throughout the kinetic chain, range of motion, and strength characteristics specific to the thrower as well as proper tissue loading principles. It is important that these athletes are not progressed too quickly through their programs and that a criteria-based progression is followed. They should have normalized range of motion, strength, and scapular mechanics, followed by a sound plyometric progression. Once this is achieved, they are advanced to an interval throwing program with increasing distance, effort, and volume which should be tracked for workload, making sure they do not throw more than their body is prepared for.

Acute Effect of Countermovement Jumping on Throwing Performance in Track and Field Athletes During Competition.

PubMed

Karampatsos, Giorgos P; Korfiatis, Panagiotis G; Zaras, Nikolaos D; Georgiadis, Giorgos V; Terzis, Gerasimos D

2017-02-01

Karampatsos, GP, Korfiatis, PG, Zaras, ND, Georgiadis, GV, and Terzis, GD. Acute effect of countermovement jumping on throwing performance in track and field athletes during competition. J Strength Cond Res 32(1): 359-364, 2017-The purpose of the study was to investigate whether performing 3 consecutive countermovement jumps (CMJs) just before an attempt enhances performance in track and field throwers during competition. Twelve shot putters, 8 hammer throwers, 9 discus throwers, and 3 javelin throwers of both sexes participated in the study. They performed 3 maximal CMJs 85 ± 12 seconds before the second, fourth, and sixth attempt during 3 different official competitions of national level. Maximal strength (1 repetition maximum [1RM]) in squat and bench press was measured 1 week after the competition. Mean throwing performance was significantly higher after the CMJs intervention (2.66 ± 4.3%, range of increase 0.02-18.98%, p = 0.0001). Similarly, maximum throwing performance was significantly higher after the CMJs (2.76 ± 3.29%, range of increase 0.09-13.93%, p = 0.0009). All but 2 athletes increased their best performance after the CMJs. The percentage increase in performance was similar between sexes (male athletes 2.56 ± 3.01%; female athletes 3.06 ± 3.76%, p = 0.677), but it was higher for the "lighter throws" (discus and javelin throw: 4.66 ± 4.11%) compared with the "heavier throws" (shot and hammer throw: 1.62 ± 2.04%, p = 0.008). The percentage increase in performance was not significantly correlated with 1RM squat or bench press, anthropometric characteristics, and personal best performance. These results suggest that performing 3 CMJs approximately 1 minute before an attempt may increase track and field throwing performance during competition.

Comparing the tensile strength of square and reversing half-hitch alternating post knots

PubMed Central

Wu, Vincent; Sykes, Edward A.; Mercer, Dale; Hopman, Wilma M.; Tang, Ephraim

2017-01-01

Background Square knots are the gold standard in hand-tie wound closure, but are difficult to reproduce in deep cavities, inadvertently resulting in slipknots. The reversing half-hitch alternating post (RHAP) knot has been suggested as an alternative owing to its nonslip nature and reproducibility in limited spaces. We explored whether the RHAP knot is noninferior to the square knot by assessing tensile strength. Methods We conducted 10 trials for each baseline and knot configuration, using 3–0 silk and 3–0 polyglactin 910 sutures. We compared tensile strength between knot configurations at the point of knot failure between slippage and breakage. Results Maximal failure strength (mean ± SD) in square knots was reached with 4-throw in both silk (30 ± 1.5 N) and polyglactin 910 (39 ± 12 N). For RHAP knots, maximal failure strength was reached at 5-throw for both silk (31 ± 1.5 N) and polyglactin 910 (41 ± 13 N). In both sutures, there were no strength differences between 3-throw square and 4-throw RHAP, between 4-throw square and 5-throw RHAP, or between 5-throw square and 6-throw RHAP knots. Polyglactin 910 sutures, in all knot configurations, were more prone to slippage than silk sutures (p < 0.001). Conclusion The difference in mean tensile strength could be attributed to the proportion of knot slippage versus breakage, which is material-dependent. Future studies can re-evaluate findings in monofilament sutures and objectively assess the reproducibility of square and RHAP knots in deep cavities. Our results indicate that RHAP knots composed of 1 extra throw provide equivalent strength to square knots and may be an alternative when performing hand-ties in limited cavities with either silk or polyglactin 910 sutures. PMID:28327276

Comparing the tensile strength of square and reversing half-hitch alternating post knots.

PubMed

Wu, Vincent; Sykes, Edward A; Mercer, Dale; Hopman, Wilma M; Tang, Ephraim

2017-06-01

Square knots are the gold standard in hand-tie wound closure, but are difficult to reproduce in deep cavities, inadvertently resulting in slipknots. The reversing half-hitch alternating post (RHAP) knot has been suggested as an alternative owing to its nonslip nature and reproducibility in limited spaces. We explored whether the RHAP knot is noninferior to the square knot by assessing tensile strength. We conducted 10 trials for each baseline and knot configuration, using 3-0 silk and 3-0 polyglactin 910 sutures. We compared tensile strength between knot configurations at the point of knot failure between slippage and breakage. Maximal failure strength (mean ± SD) in square knots was reached with 4-throw in both silk (30 ± 1.5 N) and polyglactin 910 (39 ± 12 N). For RHAP knots, maximal failure strength was reached at 5-throw for both silk (31 ± 1.5 N) and polyglactin 910 (41 ± 13 N). In both sutures, there were no strength differences between 3-throw square and 4-throw RHAP, between 4-throw square and 5-throw RHAP, or between 5-throw square and 6-throw RHAP knots. Polyglactin 910 sutures, in all knot configurations, were more prone to slippage than silk sutures ( p < 0.001). The difference in mean tensile strength could be attributed to the proportion of knot slippage versus breakage, which is material-dependent. Future studies can re-evaluate findings in monofilament sutures and objectively assess the reproducibility of square and RHAP knots in deep cavities. Our results indicate that RHAP knots composed of 1 extra throw provide equivalent strength to square knots and may be an alternative when performing hand-ties in limited cavities with either silk or polyglactin 910 sutures.

An Invitation to Play.

ERIC Educational Resources Information Center

Lange, Jenny; Zieher, Connie

The manual is intended to provide suggestions for play to parents of young children with exceptional educational needs. Nineteen types of activities are described and pictured, including make believe with boxes, dress-up activities, kitchen play, bubbles, small motor activities using beans and buttons, use of throw-away materials, painting,…

Effect of different training programs on the velocity of overarm throwing: a brief review.

PubMed

van den Tillaar, Roland

2004-05-01

Throwing velocity in overarm throwing is of major importance in sports like baseball, team handball, javelin, and water polo. The purpose of this literature review was to give an overview of the effect of different training programs on the throwing velocity in overarm throwing, provide a theoretical framework that explains findings, and give some practical applications based on these findings. The training studies were divided into 4 categories: (a) specific resistance training with an overload of velocity, (b) specific resistance training with an overload of force, (c) specific resistance training with a combination of overload of force and velocity, and (d) general resistance training according to the overload of force. Each category is presented and discussed.

The Solar Ultraviolet Magnetograph Investigation Sounding Rocket Program

NASA Technical Reports Server (NTRS)

West, E. A.; Kobayashi, K.; Davis, J. M.; Gary, G. A.

2007-01-01

This paper will describe the objectives of the Marshall Space Flight Center (MSFC) Solar Ultraviolet Magnetograph Investigation (SUMI) and the unique optical components that have been developed to meet those objectives. A sounding rocket payload has been developed to test the feasibility of magnetic field measurements in the Sun's transition region. The optics have been optimized for simultaneous measurements of two magnetic sensitive lines formed in the transition region (CIV at 1550 A and MgII at 2800 A). This paper will concentrate on the polarization properties SUMI's toroidal varied-line-space (TVLS) gratings and its system level testing as we prepare to launch in the Summer of 2008.

Near Space Environments: Tethering Systems

NASA Technical Reports Server (NTRS)

Lucht, Nolan R.

2013-01-01

Near Space Environments, the Rocket University (Rocket U) program dealing with high altitude balloons carrying payloads into the upper earth atmosphere is the field of my project. The tethering from balloon to payload is the specific system I am responsible for. The tethering system includes, the lines that tie the payload to the balloon, as well as, lines that connect payloads together, if they are needed, as well as how to sever the tether to release payloads from the balloon. My objective is to design a tethering system that will carry a payload to any desired altitude and then sever by command at any given point during flight.

The use of Congreve-type war Rockets by the Spanish in the 19th century: A chronology

NASA Technical Reports Server (NTRS)

Sancho, P. M.

1977-01-01

A yearly account of military uses, by the Spanish, of Congreve war rockets is given, from the year 1810 until 1895. Events prior to the 19th century are also recorded which include the use of rockets against the Moors of Valencia and documentation, from literature of that period, relating to rocket applications.

Rocket Science 101 Interactive Educational Program

NASA Technical Reports Server (NTRS)

Armstrong, Dennis; Funkhouse, Deborah; DiMarzio, Donald

2007-01-01

To better educate the public on the basic design of NASA s current mission rockets, Rocket Science 101 software has been developed as an interactive program designed to retain a user s attention and to teach about basic rocket parts. This program also has helped to expand NASA's presence on the Web regarding educating the public about the Agency s goals and accomplishments. The software was designed using Macromedia s Flash 8. It allows the user to select which type of rocket they want to learn about, interact with the basic parts, assemble the parts to create the whole rocket, and then review the basic flight profile of the rocket they have built.

Russian Rocket Engine Test

NASA Technical Reports Server (NTRS)

1998-01-01

NASA engineers successfully tested a Russian-built rocket engine on November 4, 1998 at the Marshall Space Flight Center (MSFC) Advanced Engine Test Facility, which had been used for testing the Saturn V F-1 engines and Space Shuttle Main engines. The MSFC was under a Space Act Agreement with Lockheed Martin Astronautics of Denver to provide a series of test firings of the Atlas III propulsion system configured with the Russian-designed RD-180 engine. The tests were designed to measure the performance of the Atlas III propulsion system, which included avionics and propellant tanks and lines, and how these components interacted with the RD-180 engine. The RD-180 is powered by kerosene and liquid oxygen, the same fuel mix used in Saturn rockets. The RD-180, the most powerful rocket engine tested at the MSFC since Saturn rocket tests in the 1960s, generated 860,000 pounds of thrust.

Relationship between sitting volleyball performance and field fitness of sitting volleyball players in Korea

PubMed Central

Jeoung, Bogja

2017-01-01

The purpose of this study was to evaluate the relationship between sitting volleyball performance and the field fitness of sitting volleyball players. Forty-five elite sitting volleyball players participated in 10 field fitness tests. Additionally, the players’ head coach and coach assessed their volleyball performance (receive and defense, block, attack, and serve). Data were analyzed with SPSS software version 21 by using correlation and regression analyses, and the significance level was set at P< 0.05. The results showed that chest pass, overhand throw, one-hand throw, one-hand side throw, splint, speed endurance, reaction time, and graded exercise test results had a statistically significant influence on the players’ abilities to attack, serve, and block. Grip strength, t-test, speed, and agility showed a statistically significant relationship with the players’ skill at defense and receive. Our results showed that chest pass, overhand throw, one-hand throw, one-hand side throw, speed endurance, reaction time, and graded exercise test results had a statistically significant influence on volleyball performance. PMID:29326896

Clinical measurement of the dart throwing motion of the wrist: variability, accuracy and correction.

PubMed

Vardakastani, Vasiliki; Bell, Hannah; Mee, Sarah; Brigstocke, Gavin; Kedgley, Angela E

2018-01-01

Despite being functionally important, the dart throwing motion is difficult to assess accurately through goniometry. The objectives of this study were to describe a method for reliably quantifying the dart throwing motion using goniometric measurements within a healthy population. Wrist kinematics of 24 healthy participants were assessed using goniometry and optical motion tracking. Three wrist angles were measured at the starting and ending points of the motion: flexion-extension, radial-ulnar deviation and dart throwing motion angle. The orientation of the dart throwing motion plane relative to the flexion-extension axis ranged between 28° and 57° among the tested population. Plane orientations derived from optical motion capture differed from those calculated through goniometry by 25°. An equation to correct the estimation of the plane from goniometry measurements was derived. This was applied and differences in the orientation of the plane were reduced to non-significant levels, enabling the dart throwing motion to be measured using goniometry alone.

Comparison of the backward overhead medicine ball throw to power production in college football players.

PubMed

Mayhew, Jerry L; Bird, Michael; Cole, Mary L; Koch, Alex J; Jacques, Jeff A; Ware, John S; Buford, Brittney N; Fletcher, Kate M

2005-08-01

The purpose of this study was to determine the relationship of the backward overhead medicine ball (BOMB) throw to power production in college football players. Forty National Collegiate Athletic Association Division II college football players were studied at the end of an 8-week off-season conditioning program for power output determined from a countermovement vertical jump on a force plate and for maximal distance in the standing BOMB throw. Although the reliability of the BOMB test was high (interclass correlation coefficient = 0.86), there was a significant learning effect across 3 trials (p < 0.01). Peak and average powers generated during the vertical jump correlated moderately but significantly with the best BOMB throw distance (r = 0.59 and 0.63, respectively). Considering power relative to body mass or lean body mass failed to produce significant correlations with BOMB throw distance (r = 0.27 and 0.28, respectively). Therefore, the BOMB throw may have limited potential as a predictor of total body explosive power in college football players.

67. Photograph of line drawing. PLANS AND SECTIONS OF 20,000 ...

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

67. Photograph of line drawing. PLANS AND SECTIONS OF 20,000 POUND MOTOR TEST AND LAUNCH FACILITY ('BLAST PIT'), DECEMBER 1945 - White Sands Missile Range, V-2 Rocket Facilities, Near Headquarters Area, White Sands, Dona Ana County, NM

68. Photograph of line drawing. SECTIONS AND DETAILS OF 20,000 ...

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

68. Photograph of line drawing. SECTIONS AND DETAILS OF 20,000 POUND MOTOR TEST AND LAUNCH FACILITY ('BLAST PIT'), DECEMBER 1945 - White Sands Missile Range, V-2 Rocket Facilities, Near Headquarters Area, White Sands, Dona Ana County, NM

Frequent Immediate Knowledge of Results Enhances the Increase of Throwing Velocity in Overarm Handball Performance.

PubMed

Štirn, Igor; Carruthers, Jamie; Šibila, Marko; Pori, Primož

2017-02-01

In the present study, the effect of frequent, immediate, augmented feedback on the increase of throwing velocity was investigated. An increase of throwing velocity of a handball set shot when knowledge of results was provided or not provided during training was compared. Fifty female and seventy-three male physical education students were assigned randomly to the experimental or control group. All participants performed two series of ten set shots with maximal effort twice a week for six weeks. The experimental group received information regarding throwing velocity measured by a radar gun immediately after every shot, whereas the control group did not receive any feedback. Measurements of maximal throwing velocity of an ordinary handball and a heavy ball were performed, before and after the training period and compared. Participants who received feedback on results attained almost a four times greater relative increase of the velocity of the normal ball (size 2) as compared to the same intervention when feedback was not provided (8.1 ± 3.6 vs. 2.7 ± 2.9%). The velocity increases were smaller, but still significant between the groups for throws using the heavy ball (5.1 ± 4.2 and 2.5 ± 5.8 for the experimental and control group, respectively). Apart from the experimental group throwing the normal ball, no differences in velocity change for gender were obtained. The results confirmed that training oriented towards an increase in throwing velocity became significantly more effective when frequent knowledge of results was provided.

KSC-08pd1096

NASA Image and Video Library

2008-05-01

CAPE CANAVERAL, Fla. -- In Firing Room No. 1 in the Launch Control Center at NASA's Kennedy Space Center, workers line up the new equipment cabinets. The firing room will support the future Ares rocket launches as part of the Constellation Program. Future astronauts will ride to orbit on Ares I, which uses a single five-segment solid rocket booster, a derivative of the space shuttle's solid rocket booster, for the first stage. Ares will be launched from Pad 39B, which is being reconfigured from supporting space shuttle launches. The Launch Control Center firing rooms face the launch pads. Photo credit: NASA/Kim Shiflett

Evolving virtual creatures and catapults.

PubMed

Chaumont, Nicolas; Egli, Richard; Adami, Christoph

2007-01-01

We present a system that can evolve the morphology and the controller of virtual walking and block-throwing creatures (catapults) using a genetic algorithm. The system is based on Sims' work, implemented as a flexible platform with an off-the-shelf dynamics engine. Experiments aimed at evolving Sims-type walkers resulted in the emergence of various realistic gaits while using fairly simple objective functions. Due to the flexibility of the system, drastically different morphologies and functions evolved with only minor modifications to the system and objective function. For example, various throwing techniques evolved when selecting for catapults that propel a block as far as possible. Among the strategies and morphologies evolved, we find the drop-kick strategy, as well as the systematic invention of the principle behind the wheel, when allowing mutations to the projectile.

Throw Away that Telework Manual!’ - the Limitations of Existing Telework Literature in the B2C e-Business Context

DTIC Science & Technology

2004-06-01

of Case B identified the importance of a Customer Relationship Management ( CRM ) strategy in their e-business for effective telework to occur as...telework that acknowledge and take account of the heterogeneity of teleworkers. Keywords. Telework, e-Business, Customer relationship management ...to build rapport on-line with the customers makes it easier to work from outside the office. Fourthly, the employees (T3 and T4) and manager (M2

On-Line Detection and Segmentation of Sports Motions Using a Wearable Sensor.

PubMed

Kim, Woosuk; Kim, Myunggyu

2018-03-19

In sports motion analysis, observation is a prerequisite for understanding the quality of motions. This paper introduces a novel approach to detect and segment sports motions using a wearable sensor for supporting systematic observation. The main goal is, for convenient analysis, to automatically provide motion data, which are temporally classified according to the phase definition. For explicit segmentation, a motion model is defined as a sequence of sub-motions with boundary states. A sequence classifier based on deep neural networks is designed to detect sports motions from continuous sensor inputs. The evaluation on two types of motions (soccer kicking and two-handed ball throwing) verifies that the proposed method is successful for the accurate detection and segmentation of sports motions. By developing a sports motion analysis system using the motion model and the sequence classifier, we show that the proposed method is useful for observation of sports motions by automatically providing relevant motion data for analysis.

33 CFR Appendix A to Part 274 - Preventive Safety Measures in Handling of Pesticides

Code of Federal Regulations, 2011 CFR

2011-07-01

... immediately washed off with detergent and water. 7. Protective clothing is used in conjunction with... lightweight water and chemical resistant throw away type protective clothing that is impervious to herbicides... beneficial in reducing physical stress to applicators. Additional protection is afforded by protective skin...

33 CFR Appendix A to Part 274 - Preventive Safety Measures in Handling of Pesticides

Code of Federal Regulations, 2010 CFR

2010-07-01

... immediately washed off with detergent and water. 7. Protective clothing is used in conjunction with... lightweight water and chemical resistant throw away type protective clothing that is impervious to herbicides... beneficial in reducing physical stress to applicators. Additional protection is afforded by protective skin...

Evaluation of the thickness of the medial ulnar collateral ligament in junior high and high school baseball players.

PubMed

Nagamoto, Hideaki; Yamamoto, Nobuyuki; Kurokawa, Daisuke; Takahashi, Hiroyuki; Muraki, Takayuki; Tanaka, Minoru; Koike, Yoichi; Sano, Hirotaka; Itoi, Eiji

2015-07-01

Thickening of the medial ulnar collateral ligament in the throwing arm of adult baseball players is a well-known phenomenon. However, onset of the thickening is unclear among young baseball players. The purpose of this study was to evaluate the thickness of the medial ulnar collateral ligament in junior high and high school baseball players. Seventy-one uninjured and asymptomatic junior high and high school baseball players were included in the study. Participants underwent physical examination after completing a questionnaire, followed by ultrasonographic evaluation. The thickness of the medial ulnar collateral ligament was measured bilaterally. The thickness of the throwing and non-throwing sides in high school and junior high school baseball players, and within each group, was compared and statistically analyzed. The medial ulnar collateral ligament in the throwing arm of high school baseball players was thicker than that in the non-throwing arm (5.5 vs. 4.4 mm), although no significant difference was seen in junior high school baseball players. High school baseball players showed a significantly thicker medial ulnar collateral ligament in the throwing arm than junior high school baseball players. Thickening of the medial ulnar collateral ligament in the throwing arm of asymptomatic and uninjured baseball players may begin by the time the players reach high school.

Biomechanical analysis of the sidearm throwing motion for distance of a flying disc: a comparison of skilled and unskilled ultimate players.

PubMed

Sasakawa, Kei; Sakurai, Shinji

2008-09-01

Joint angles of the throwing limb were examined from the acceleration phase up until release for the sidearm throwing motion when using a flying disc. 17 individuals (ten skilled, seven unskilled) threw a disc as far as possible ten times. Throwing motions were recorded using three-dimensional high-speed videography. The initial condition of disc release and joint angle kinematics of the upper limb during the throwing motion were obtained. Mean (+/- standard deviation) throwing distance and disc spin rate were significantly greater for skilled throwers (51.4 +/- 6.6 m, 12.9 +/- 1.3 rps) than for unskilled throwers (29.5 +/- 7.6 m, 9.4 +/- 1.3 rps), although there was no significant difference in initial velocity of the disc between the two groups (skilled: 21.7 +/- 1.7m/s; unskilled: 20.7 +/- 2.5m/s). A marked difference in motion of supination/pronation of the forearm before disc release was identified, with the forearm supinated in the final acceleration phase leading up to disc release for the unskilled participants, while the forearm was pronated in the same phase for the skilled participants. These differences in joint kinematics could be related to differences in disc spin rate, and thus led to the substantial differences in throwing distance.

Astro Camp is a blast!

NASA Image and Video Library

2006-06-08

An Astro Camp counselor and her campers perform a science experiment to learn what types of `fuel' will best propel their 'rockets.' Stennis Space Center's popular series of day camps have campers design, build and test model rockets based on the principles that would be used to build different types of rockets suitable for a mission to the moon or Mars. They learn details like how far they would travel, how long it would take, what supplies they would need and how to survive in that environment.

3. SOUTHWEST REAR, WITH RAILROAD LINE AT RIGHT. HIGH PRESSURE ...

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

3. SOUTHWEST REAR, WITH RAILROAD LINE AT RIGHT. HIGH PRESSURE HELIUM STORAGE TANKS AT LEFT. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Helium Compression Plant, Test Area 1-115, intersection of Altair & Saturn Boulevards, Boron, Kern County, CA

19. TRAVELING CRANE ATOP SUPERSTRUCTURE, FROM RUN LINE DECK. Looking ...

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

19. TRAVELING CRANE ATOP SUPERSTRUCTURE, FROM RUN LINE DECK. Looking up to north northeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

63. Photograph of line drawing. SITE PLAN OF GANTRY CRANE ...

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

63. Photograph of line drawing. SITE PLAN OF GANTRY CRANE TRACKS AND 20,000 POUND MOTOR TEST AND LAUNCH FACILITY ('BLAST PIT'), OCTOBER 1946 - White Sands Missile Range, V-2 Rocket Facilities, Near Headquarters Area, White Sands, Dona Ana County, NM

Measurements of induced voltages and currents in a distribution power line and associated atmospheric parameters

NASA Technical Reports Server (NTRS)

Santiago-Perez, Julio

1988-01-01

The frequency and intensity of thunderstorms around the Kennedy Space Center (KSC) has affected scheduled launch, landing, and other ground operations for many years. In order to protect against and provide safe working facilities, KSC has performed and hosted several studies on lightning phenomena. For the reasons mentioned above, KSC has established the Atmospheric Science Field Laboratory (ASFL). At these facilities KSC launches wire-towing rockets into thunderstorms to trigger natural lightning to the launch site. A program named Rocket Triggered Lightning Program (RTLP) is being conducted at the ASFL. This report calls for two of the experiments conducted in the summer 1988 Rocket Triggered Lightning Program. One experiment suspended an electric field mill over the launching areas from a balloon about 500 meters high to measure the space charges over the launching area. The other was to connect a waveform recorder to a nearby distribution power line to record currents and voltages wave forms induced by natural and triggered lightning.

Measurements of induced voltages and currents in a distribution power line and associated atmospheric parameters

NASA Astrophysics Data System (ADS)

Santiago-Perez, Julio

1988-10-01

The frequency and intensity of thunderstorms around the Kennedy Space Center (KSC) has affected scheduled launch, landing, and other ground operations for many years. In order to protect against and provide safe working facilities, KSC has performed and hosted several studies on lightning phenomena. For the reasons mentioned above, KSC has established the Atmospheric Science Field Laboratory (ASFL). At these facilities KSC launches wire-towing rockets into thunderstorms to trigger natural lightning to the launch site. A program named Rocket Triggered Lightning Program (RTLP) is being conducted at the ASFL. This report calls for two of the experiments conducted in the summer 1988 Rocket Triggered Lightning Program. One experiment suspended an electric field mill over the launching areas from a balloon about 500 meters high to measure the space charges over the launching area. The other was to connect a waveform recorder to a nearby distribution power line to record currents and voltages wave forms induced by natural and triggered lightning.

Effects of Six Weeks of Medicine Ball Training on Throwing Velocity, Throwing Precision, and Isokinetic Strength of Shoulder Rotators in Female Handball Players.

PubMed

Raeder, Christian; Fernandez-Fernandez, Jaime; Ferrauti, Alexander

2015-07-01

The aim of this study was to investigate the effects of 6 weeks of medicine ball training (MBT) on throwing velocity, throwing precision, and isokinetic strength of shoulder rotators in competitive female handball players. Twenty-eight players (mean ± SD; age: 20.8 ± 3.3 years, height: 170.5 ± 5.6 cm, body mass: 65.2 ± 8.0 kg) were randomly assigned to an MBT group (TG; n = 15) and a control group (CG; n = 13). TG performed a supervised MBT program, 3 times a week for a total of 6 weeks, focusing on handball-specific movement patterns. Both groups, TG and CG, also conducted a supervised shoulder injury prevention program with elastic tubes, as part of the warm-up, finishing with regular handball throws. Results showed a significant group × time interaction in throwing velocity (p < 0.001) with the TG posttest results being significantly higher compared with CG (d = 2.1), and also a significant main time effect (p < 0.001), with an increase in throwing velocity of 14% (d = 3.0) and 3.7% (d = 0.3) for both TG and CG, respectively. Throwing precision did not significantly differ between groups and time points. Isokinetic strength measures revealed a significant group × time interaction (p ≤ 0.05) with the TG posttest results being significantly higher compared with CG (d = 0.9) and also a significant main time effect (p < 0.01) with an increase of 15% (d = 0.9) in concentric shoulder internal rotation at 180°·s⁻¹ in the dominant arm in TG, whereas no significant changes occurred in CG. The present results indicate that 6 weeks of MBT elicit significant improvements in functional performance (i.e., throwing velocity) in female handball players, whereas throwing precision remained unaffected. Medicine ball training exercises seem to be a useful and inexpensive strength training strategy in enhancing functional performance by closely mimicking sport-specific movement activities.

Where Are You Throwing the Ball? I Better Watch Your Body, Not Just Your Arm!

PubMed

Maselli, Antonella; Dhawan, Aishwar; Cesqui, Benedetta; Russo, Marta; Lacquaniti, Francesco; d'Avella, Andrea

2017-01-01

The ability to intercept or avoid a moving object, whether to catch a ball, snatch one's prey, or avoid the path of a predator, is a skill that has been acquired throughout evolution by many species in the animal kingdom. This requires processing early visual cues in order to program anticipatory motor responses tuned to the forthcoming event. Here, we explore the nature of the early kinematics cues that could inform an observer about the future direction of a ball projected with an unconstrained overarm throw. Our goal was to pinpoint the body segments that, throughout the temporal course of the throwing action, could provide key cues for accurately predicting the side of the outgoing ball. We recorded whole-body kinematics from twenty non-expert participants performing unconstrained overarm throws at four different targets placed on a vertical plane at 6 m distance. In order to characterize the spatiotemporal structure of the information embedded in the kinematics of the throwing action about the outgoing ball direction, we introduced a novel combination of dimensionality reduction and machine learning techniques. The recorded kinematics clearly shows that throwing styles differed considerably across individuals, with corresponding inter-individual differences in the spatio-temporal structure of the thrower predictability. We found that for most participants it is possible to predict the region where the ball hit the target plane, with an accuracy above 80%, as early as 400-500 ms before ball release. Interestingly, the body parts that provided the most informative cues about the action outcome varied with the throwing style and during the time course of the throwing action. Not surprisingly, at the very end of the action, the throwing arm is the most informative body segment. However, cues allowing for predictions to be made earlier than 200 ms before release are typically associated to other body parts, such as the lower limbs and the contralateral arm. These findings are discussed in the context of the sport-science literature on throwing and catching interactive tasks, as well as from the wider perspective of the role of sensorimotor coupling in interpersonal social interactions.

Graduate Student Researchers Program (GSRP)

NASA Technical Reports Server (NTRS)

Westerhoff, John

2004-01-01

An advanced concept in in-space transportation currently being studied is the Momentum-Exchange/Electrodynamic Reboost Tether System (MXER). The MXER system is a permanently orbiting platform designed to boost payloads from low earth orbit (LEO). Unlike conventional rockets that use propellants, MXER acts as a large momentum wheel, imparting a Av to a payload at the expense of its own orbital energy. After throwing a payload, the system reboosts itself using an electrodynamic tether to push against Earth s magnetic field and brings itself back up to an operational orbit to prepare for the next payload. The ability to reboost itself allows for continued reuse of the system without the expenditure of propellants. Considering the cost of lifting propellant from the ground to LEO to do the same Av boost at $10000 per pound, the system cuts the launch cost of the payload dramatically, and subsequently, the MXER system pays for itself after a small number of missions. As such, this technology is a valuable addition to NASA s mission for in-space transportation.

Effect of Core Training on Male Handball Players’ Throwing Velocity

PubMed Central

García-Ruiz, José; Cortell-Tormo, Juan Manuel; Tortosa-Martínez, Juan

2017-01-01

Abstract In handball, throwing velocity is considered to be one of the essential factors in achieving the ultimate aim of scoring a goal. The objective of the present study was to analyze the effect of a core training program on throwing velocity in 30 handball players (age 18.7 ± 3.4 years, body height 179.3 ± 7.0 cm, body mass 78.9 ± 7.7 kg), 16 of whom were in the junior category and 14 of whom were in the senior category. The 30 players were randomly divided into two groups, the control group (n = 15) and the experimental group (n = 15). For a period of ten weeks, both groups attended their regular handball training sessions (four per week), but in addition, the experimental group participated in a program specifically aimed at progressively strengthening the lumbo-pelvic region and consisting of seven exercises performed after the general warm-up in each regular session. Pre- and post-tests were carried out to analyze each player’s throwing velocity from different throwing positions and thus assess the effects of this specific training program. Statistically significant differences (p ≤ 0.05) in throwing velocity were observed between the experimental group, which presented a percentage improvement of 4.5%, and the control group, which did not show any improvement. The results seem to indicate that an increase in the strength and stability of the lumbo-pelvic region can contribute to an improvement in the kinetic chain of the specific movement of throwing in handball, thus, increasing throwing velocity. PMID:28469756

Effect of Core Training on Male Handball Players' Throwing Velocity.

PubMed

Manchado, Carmen; García-Ruiz, José; Cortell-Tormo, Juan Manuel; Tortosa-Martínez, Juan

2017-02-01

In handball, throwing velocity is considered to be one of the essential factors in achieving the ultimate aim of scoring a goal. The objective of the present study was to analyze the effect of a core training program on throwing velocity in 30 handball players (age 18.7 ± 3.4 years, body height 179.3 ± 7.0 cm, body mass 78.9 ± 7.7 kg), 16 of whom were in the junior category and 14 of whom were in the senior category. The 30 players were randomly divided into two groups, the control group (n = 15) and the experimental group (n = 15). For a period of ten weeks, both groups attended their regular handball training sessions (four per week), but in addition, the experimental group participated in a program specifically aimed at progressively strengthening the lumbo-pelvic region and consisting of seven exercises performed after the general warm-up in each regular session. Pre- and post-tests were carried out to analyze each player's throwing velocity from different throwing positions and thus assess the effects of this specific training program. Statistically significant differences (p ≤ 0.05) in throwing velocity were observed between the experimental group, which presented a percentage improvement of 4.5%, and the control group, which did not show any improvement. The results seem to indicate that an increase in the strength and stability of the lumbo-pelvic region can contribute to an improvement in the kinetic chain of the specific movement of throwing in handball, thus, increasing throwing velocity.

The differences in frontal midline theta power between successful and unsuccessful basketball free throws of elite basketball players.

PubMed

Chuang, Lan-Ya; Huang, Chung-Ju; Hung, Tsung-Min

2013-12-01

During the preparatory period of motor skill, attention is considered as one of the most vital factors for athletic performance. Electroencephalographic (EEG) indices, such as occipital α, have been employed to explore the psychological state during the preparatory period in elite athletes. The main purpose of this study was to investigate the differences in frontal midline theta (Fm θ) power during the aiming period between successful and unsuccessful basketball free throws. Fifteen skilled male basketball players were recruited and asked to perform free throws. Electroencephalogram (EEG) data were collected 2seconds prior to the initiation of the free throw and segmented into four 0.5-s epochs. The lower theta (θ1, 4-6Hz) and upper theta (θ2, 6-8Hz) power values was contrasted between the successful and unsuccessful throws. Two 2×4×6 (performance×time×electrode) ANOVAs with repeated measures were conducted separately for θ1 and θ2 power. The results indicate that θ1 power at the Fz site and θ2 power at the Fz and the F4 sites fluctuated significantly during the preparatory period for an unsuccessful throw when compared with a successful throw. Additionally, a higher Fm θ2 power was observed at the beginning of the aiming period of a successful throw. This study suggests that a stable arousal and a relatively constant amount of attention to the task prior to motor execution may facilitate athletic performance. Crown Copyright © 2013. All rights reserved.

Analysis of rocket beacon transmissions for computerized reconstruction of ionospheric densities

NASA Technical Reports Server (NTRS)

Bernhardt, P. A.; Huba, J. D.; Chaturvedi, P. K.; Fulford, J. A.; Forsyth, P. A.; Anderson, D. N.; Zalesak, S. T.

1993-01-01

Three methods are described to obtain ionospheric electron densities from transionospheric, rocket-beacon TEC data. First, when the line-of-sight from a ground receiver to the rocket beacon is tangent to the flight trajectory, the electron concentration can be obtained by differentiating the TEC with respect to the distance to the rocket. A similar method may be used to obtain the electron-density profile if the layer is horizontally stratified. Second, TEC data obtained during chemical release experiments may be interpreted with the aid of physical models of the disturbed ionosphere to yield spatial maps of the modified regions. Third, computerized tomography (CT) can be used to analyze TEC data obtained along a chain of ground-based receivers aligned along the plane of the rocket trajectory. CT analysis of TEC data is used to reconstruct a 2D image of a simulated equatorial plume. TEC data is computed for a linear chain of nine receivers with adjacent spacings of either 100 or 200 km. The simulation data are analyzed to provide an F region reconstruction on a grid with 15 x 15 km pixels. Ionospheric rocket tomography may also be applied to rocket-assisted measurements of amplitude and phase scintillations and airglow intensities.

Techniques for the measurements of the line of sight velocity of high altitude Barium clouds

NASA Technical Reports Server (NTRS)

Mende, S. B.

1981-01-01

It is demonstrated that for maximizing the scientific output of future ion cloud release experiments a new type of instrument is required which will measure the line of sight velocity of the ion cloud by the Doppler Technique. A simple instrument was constructed using a 5 cm diameter solid Fabry-Perot etalon coupled to a low light level integrating television camera. It was demonstrated that the system has both the sensitivity and spectral resolution for the detection of ion clouds and the measurement of their line of sight Doppler velocity. The tests consisted of (1) a field experiment using a rocket barium cloud release to check the sensitivity, (2) laboratory experiments to show the spectral resolving capabilities of the system. The instrument was found to be operational if the source was brighter than about 1 kilorayleigh and it had a wavelength resolution much better than .2A which corresponds to about 12 km/sec or an acceleration potential of 100 volts.

Developmental Gender Differences for Overhand Throwing in Aboriginal Australian Children

ERIC Educational Resources Information Center

Thomas, Jerry R.; Alderson, Jacqueline A.; Thomas, Katherine T.; Campbell, Amity C.; Elliott, Bruce C.

2010-01-01

In a review of 46 meta-analyses of gender differences, overhand throwing had the largest gender difference favoring boys (ES greater than 3.0). Expectations for gender-specific performances may be less pronounced in female Australian Aborigines, because historical accounts state they threw for defense and hunting. Overhand throwing velocities and…

Reduction of errors during practice facilitates fundamental movement skill learning in children with intellectual disabilities.

PubMed

Capio, C M; Poolton, J M; Sit, C H P; Eguia, K F; Masters, R S W

2013-04-01

Children with intellectual disabilities (ID) have been found to have inferior motor proficiencies in fundamental movement skills (FMS). This study examined the effects of training the FMS of overhand throwing by manipulating the amount of practice errors. Participants included 39 children with ID aged 4-11 years who were allocated into either an error-reduced (ER) training programme or a more typical programme in which errors were frequent (error-strewn, ES). Throwing movement form, throwing accuracy, and throwing frequency during free play were evaluated. The ER programme improved movement form, and increased throwing activity during free play to a greater extent than the ES programme. Furthermore, ER learners were found to be capable of engaging in a secondary cognitive task while manifesting robust throwing accuracy performance. The findings support the use of movement skills training programmes that constrain practice errors in children with ID, suggesting that such approach results in improved performance and heightened movement engagement in free play. © 2012 The Authors. Journal of Intellectual Disability Research © 2012 Blackwell Publishing Ltd.

Large Eddy Simulations of Transverse Combustion Instability in a Multi-Element Injector

DTIC Science & Technology

2016-07-27

plagued the development of liquid rocket engines and remains a large riskin the development and acquisition of new liquid rocket engines. Combustion...simulations to better understand the physics that can lead combustion instability in liquid rocket engines. Simulations of this type are able to...instabilities found in liquid rocket engines are transverse. The motivating of the experiment behind the current work is to subject the CVRC injector

Especial skill effect across age and performance level: the nature and degree of generalization.

PubMed

Czyż, S H; Breslin, G; Kwon, O; Mazur, M; Kobiałka, K; Pizlo, Z

2013-01-01

It has been claimed that an especial skill emerges after massive amounts of basketball practice. Despite this no direct evidence is available to support this claim. The authors aimed to shed light on this question. Thirty-seven male basketball players took part representing four groups: 2 groups of senior players, a cadet group, and a group of juniors. Players performed free throw shots from 7 distances including shots from the free throw line (15 ft). It was shown that an especial skill was present in senior players, but not in junior players who had only 3 years of playing experience. The authors present a descriptive model of especial skill and express it using the formalism of a hierarchical Bayesian model to fit the data and estimate the parameters. This model can account not only for the results, which indicate the presence and a substantial degree of generalizability of especial skill to nearby distances, but also for results of the original study on especial skill where it was proposed that specificity in practice leads to the emergence of the especial skill.

Carrier rockets

NASA Astrophysics Data System (ADS)

Aleksandrov, V. A.; Vladimirov, V. V.; Dmitriev, R. D.; Osipov, S. O.

This book takes into consideration domestic and foreign developments related to launch vehicles. General information concerning launch vehicle systems is presented, taking into account details of rocket structure, basic design considerations, and a number of specific Soviet and American launch vehicles. The basic theory of reaction propulsion is discussed, giving attention to physical foundations, the various types of forces acting on a rocket in flight, basic parameters characterizing rocket motion, the effectiveness of various approaches to obtain the desired velocity, and rocket propellants. Basic questions concerning the classification of launch vehicles are considered along with construction and design considerations, aspects of vehicle control, reliability, construction technology, and details of structural design. Attention is also given to details of rocket motor design, the basic systems of the carrier rocket, and questions of carrier rocket development.

Mid-humerus adaptation in fast pitch softballers and the impact of throwing mechanics

PubMed Central

Bogenschutz, Elizabeth D.; Smith, Heather D.; Warden, Stuart J.

2011-01-01

Purpose Throwing is a vigorous activity that generates large internal loads. There is limited evidence of the effect of these loads on bone adaptation. The aim of this study was to investigate the: 1) magnitude of bone adaptation within the midshaft humerus of female fast-pitch softball players and 2) influence of throwing mechanics (windmill vs. overhand throwing) on the magnitude of adaptation. Methods Midshaft humeral bone mass, structure and estimated strength were assessed via peripheral quantitative computed tomography in fast-pitch softball players (throwers; n=15) and matched controls (controls; n=15). The effect of throwing was examined by comparing dominant-to-nondominant differences in throwers to controls, while the influence of mechanics was determined by comparing dominant-to-nondominant differences in throwers who primarily play as pitcher (windmill thrower), catcher (overhand thrower) or fielder (overhand thrower). Results Throwers had greater dominant-to-nondominant difference in midshaft humeral bone mass, structure and estimated strength relative to controls (all P<0.05). The largest effect was for estimated torsional strength with throwers having a mean dominant-to-nondominant difference of 22.5% (range, 6.7% to 43.9%) compared to 4.4% (range, -8.3% to 17.5%) in controls (P<0.001). Throwing mechanics appeared to influence the magnitude of skeletal adaptation, with overhand throwers having more than double dominant-to-nondominant difference in midshaft humeral bone mass, structure and estimated strength than windmill throwers (all P<0.05). Conclusion Throwing induces substantial skeletal adaptation at the midshaft humerus of the dominant upper extremity. Throwing mechanics appears to the influence the magnitude of adaptation as catchers and fielders (overhand throwers) had twice as much adaptation as pitchers (windmill throwers). The latter finding may have implications for skeletal injury risk at the midshaft humerus in throwing athletes. PMID:21311354

Effects of 4-Week Training Intervention with Unknown Loads on Power Output Performance and Throwing Velocity in Junior Team Handball Players.

PubMed

Sabido, Rafael; Hernández-Davó, Jose Luis; Botella, Javier; Moya, Manuel

2016-01-01

To compare the effect of 4-week unknown vs known loads strength training intervention on power output performance and throwing velocity in junior team handball players. Twenty-eight junior team-handball players (17.2 ± 0.6 years, 1.79 ± 0.07 m, 75.6 ± 9.4 kg)were divided into two groups (unknown loads: UL; known loads: KL). Both groups performed two sessions weekly consisting of four sets of six repetitions of the bench press throw exercise, using the 30%, 50% and 70% of subjects' individual 1 repetition maximum (1RM). In each set, two repetitions with each load were performed, but the order of the loads was randomised. In the KL group, researchers told the subjects the load to mobilise prior each repetition, while in the UL group, researchers did not provide any information. Maximal dynamic strength (1RM bench press), power output (with 30, 50 and 70% of 1RM) and throwing velocity (7 m standing throw and 9 m jumping throw) were assessed pre- and post-training intervention. Both UL and KL group improved similarly their 1RM bench press as well as mean and peak power with all loads. There were significant improvements in power developed in all the early time intervals measured (150 ms) with the three loads (30, 50, 70% 1RM) in the UL group, while KL only improved with 30% 1RM (all the time intervals) and with 70% 1RM (at certain time intervals). Only the UL group improved throwing velocity in both standing (4.7%) and jumping (5.3%) throw (p > 0.05). The use of unknown loads has led to greater gains in power output in the early time intervals as well as to increases in throwing velocity compared with known loads. Therefore unknown loads are of significant practical use to increase both strength and in-field performance in a short period of training.

Upper body contributions to power generation during rapid, overhand throwing in humans.

PubMed

Roach, Neil T; Lieberman, Daniel E

2014-06-15

High-speed and accurate throwing is a distinctive human behavior. Achieving fast projectile speeds during throwing requires a combination of elastic energy storage at the shoulder, as well as the transfer of kinetic energy from proximal body segments to distal segments. However, the biomechanical bases of these mechanisms are not completely understood. We used inverse dynamics analyses of kinematic data from 20 baseball players fitted with four different braces that inhibit specific motions to test a model of power generation at key joints during the throwing motion. We found that most of the work produced during throwing is generated at the hips, and much of this work (combined with smaller contributions from the pectoralis major) is used to load elastic elements in the shoulder and power the rapid acceleration of the projectile. Despite rapid angular velocities at the elbow and wrist, the restrictions confirm that much of the power generated to produce these distal movements comes from larger proximal segments, such as the shoulder and torso. Wrist hyperextension enhances performance only modestly. Together, our data also suggest that heavy reliance on elastic energy storage may help explain some common throwing injuries and can provide further insight into the evolution of the upper body and when our ancestors first developed the ability to produce high-speed throws. © 2014. Published by The Company of Biologists Ltd.

Influence Of Opposition On Ball Velocity In The Handball Jump Throw

PubMed Central

Rivilla-Garcia, Jesús; Grande, Ignacio; Sampedro, Javier; Van Den Tillaar, Roland

2011-01-01

The purpose of the present study was to investigate the influence of different degrees of opposition on ball velocity in the jump throw in elite, amateur and adolescent team handball players. Thus, one hundred and nineteen elite, amateur and under 18 team handball players performed jump throws under three different conditions: 1) without opposition, 2) with the opposition of the goalkeeper and 3) with the opposition of the goalkeeper and a defensive player. The degree of opposition was found to have a negative effect on ball velocity in all three groups (p < 0.001). Furthermore, the level of competition had a positive effect on ball velocity (p < 0.001). However, no interaction was found between the level of competition and the degree of opposition on ball velocity (p = 0.178). The findings of this study indicate that an increase of external stimuli probably influences throwing kinematics and thereby maximal ball velocity. However, experience does not seem to be a factor that can reduce the influence of these external stimuli. Key points The degree of opposition had a negative effect upon ball throwing velocity in elite, amateur and adolescent handball players in the jump throw. It indicated that an increase of external stimuli influences the execution of throwing. Experience does not seem to be a factor that can reduce the influence of these external stimuli. PMID:24150629

Reducing errors benefits the field-based learning of a fundamental movement skill in children.

PubMed

Capio, C M; Poolton, J M; Sit, C H P; Holmstrom, M; Masters, R S W

2013-03-01

Proficient fundamental movement skills (FMS) are believed to form the basis of more complex movement patterns in sports. This study examined the development of the FMS of overhand throwing in children through either an error-reduced (ER) or error-strewn (ES) training program. Students (n = 216), aged 8-12 years (M = 9.16, SD = 0.96), practiced overhand throwing in either a program that reduced errors during practice (ER) or one that was ES. ER program reduced errors by incrementally raising the task difficulty, while the ES program had an incremental lowering of task difficulty. Process-oriented assessment of throwing movement form (Test of Gross Motor Development-2) and product-oriented assessment of throwing accuracy (absolute error) were performed. Changes in performance were examined among children in the upper and lower quartiles of the pretest throwing accuracy scores. ER training participants showed greater gains in movement form and accuracy, and performed throwing more effectively with a concurrent secondary cognitive task. Movement form improved among girls, while throwing accuracy improved among children with low ability. Reduced performance errors in FMS training resulted in greater learning than a program that did not restrict errors. Reduced cognitive processing costs (effective dual-task performance) associated with such approach suggest its potential benefits for children with developmental conditions. © 2011 John Wiley & Sons A/S.

Development and validation of a method to directly measure the cable force during the hammer throw.

PubMed

Brice, Sara M; Ness, Kevin F; Rosemond, Doug; Lyons, Keith; Davis, Mark

2008-05-01

The development of cable force during hammer-throw turns is crucial to the throw distance. In this paper, we present a method that is capable of measuring cable force in real time and, as it does not interfere with technique, it is capable of providing immediate feedback to coaches and athletes during training. A strain gauge was mounted on the wires of three hammers to measure the tension in the wire and an elite male hammer thrower executed three throws with each hammer. The output from the gauges was recorded by a data logger positioned on the lower back of the thrower. The throws were captured by three high-speed video cameras and the three-dimensional position of the hammer's head was determined by digitizing the images manually. The five best throws were analysed. The force acting on the hammer's head was calculated from Newton's second law of motion and this was compared with the force measured via the strain gauge. Qualitatively the time dependence of the two forces was essentially the same, although the measured force showed more detail in the troughs of the force-time curves. Quantitatively the average difference between the measured and calculated forces over the five throws was 76 N, which corresponds to a difference of 3.8% for a cable force of 2000 N.

Long term changes of the throwing arm of former elite javelin throwers.

PubMed

Schmitt, H; Hansmann, H J; Brocai, D R; Loew, M

2001-05-01

The aim of this study was to determine long term changes in shoulder and elbow joints of former elite javelin throwers. Twenty-one elite javelin throwers were examined at an average of 19 years after the end of their high performance phase. Mean age at examination was 50 years. Functional assessment of both shoulders was determined by the Constant-score. The shoulder of the throwing arm was examined by magnetic resonance imaging. Both elbow joints were examined clinically and radiographically. Five athletes complained about transient shoulder pain in their throwing arm affecting activities of daily living, fourteen athletes had a deficit of internal rotation of at least ten degrees. Constant-scores of throwing arms were six points lower than those of non-throwing arms (P < 0.05). Complete ruptures and partial tears of the rotator cuff were frequent. Three athletes complained about transient elbow pain in their throwing arm affecting activities of daily living; ten athletes had a deficit of extension of more than five degrees. All dominant elbows had advanced arthrotic alterations (osteophytes, sclerosis) compared to the non-dominant side. Athletes who trained with weights of more than 3 kg had a significantly higher risk of degenerative changes than athletes who did not (P < 0.01). We therefore recommend to avoid throwing training with weights of more than 3 kg.

Active Region Soft X-Ray Spectra as Observed Using Sounding Rocket Measurements from the Solar Aspect Monitor (SAM), - a Modified SDO/EVE Instrument

NASA Astrophysics Data System (ADS)

Wieman, S. R.; Didkovsky, L. V.; Woods, T. N.; Jones, A. R.; Caspi, A.; Warren, H. P.

2015-12-01

Observations of solar active regions (ARs) in the soft x-ray spectral range (0.5 to 3.0 nm) were made on sounding rocket flight NASA 36.290 using a modified Solar Aspect Monitor (SAM), a pinhole camera on the EUV Variability Experiment (EVE) sounding rocket instrument. The suite of EVE rocket instruments is designed for under-flight calibrations of the orbital EVE on SDO. While the sounding rocket EVE instrument is for the most part a duplicate of the EVE on SDO, the SAM channel on the rocket version was modified in 2012 to include a free-standing transmission grating so that it could provide spectrally resolved images of the solar disk with the best signal to noise ratio for the brightest features on it, such as ARs. Calibrations of the EVE sounding rocket instrument at the National Institute of Standards and Technology Synchrotron Ultraviolet Radiation Facility (NIST SURF) have provided a measurement of the SAM absolute spectral response function and a mapping of wavelength separation in the grating diffraction pattern. For solar observations, this spectral separation is on a similar scale to the spatial size of the AR on the CCD, so dispersed AR images associated with emission lines of similar wavelength tend to overlap. Furthermore, SAM shares a CCD detector with MEGS-A, a separate EVE spectrometer channel, and artifacts of the MEGS-A signal (a set of bright spectral lines) appear in the SAM images. For these reasons some processing and analysis of the solar images obtained by SAM must be performed in order to determine spectra of the observed ARs. We present a method for determining AR spectra from the SAM rocket images and report initial soft X-ray spectra for two of the major active regions (AR11877 and AR11875) observed on flight 36.290 on 21 October 2013 at about 18:30 UT. We also compare our results with concurrent measurements from other solar soft x-ray instrumentation.

Theory, Image Simulation, and Data Analysis of Chemical Release Experiments

NASA Technical Reports Server (NTRS)

Wescott, Eugene M.

1994-01-01

The final phase of Grant NAG6-1 involved analysis of physics of chemical releases in the upper atmosphere and analysis of data obtained on previous NASA sponsored chemical release rocket experiments. Several lines of investigation of past chemical release experiments and computer simulations have been proceeding in parallel. This report summarizes the work performed and the resulting publications. The following topics are addressed: analysis of the 1987 Greenland rocket experiments; calculation of emission rates for barium, strontium, and calcium; the CRIT 1 and 2 experiments (Collisional Ionization Cross Section experiments); image calibration using background stars; rapid ray motions in ionospheric plasma clouds; and the NOONCUSP rocket experiments.

An Optimal Basketball Free Throw

ERIC Educational Resources Information Center

Seppala-Holtzman, David

2012-01-01

A basketball player attempting a free throw has two parameters under his or her control: the angle of elevation and the force with which the ball is thrown. We compute upper and lower bounds for the initial velocity for suitable values of the angle of elevation, generating a subset of the configuration space of all successful free throws. A…

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…

Changing Throwing Pattern: Instruction and Control Parameter

ERIC Educational Resources Information Center

Southard, Dan

2006-01-01

The purpose of this study was to determine the effects of instruction and scaling up a control parameter (velocity of throw) on changes in throwing pattern. Sixty adult female throwers (ages 20-26 years) were randomly placed into one of four practice conditions: (a) scale up on velocity with no instruction, (b) maintain constant velocity with no…

Low-Resolution Near-infrared Stellar Spectra Observed by the Cosmic Infrared Background Experiment (CIBER)

NASA Astrophysics Data System (ADS)

Kim, Min Gyu; Lee, Hyung Mok; Arai, Toshiaki; Bock, James; Cooray, Asantha; Jeong, Woong-Seob; Kim, Seong Jin; Korngut, Phillip; Lanz, Alicia; Lee, Dae Hee; Lee, Myung Gyoon; Matsumoto, Toshio; Matsuura, Shuji; Nam, Uk Won; Onishi, Yosuke; Shirahata, Mai; Smidt, Joseph; Tsumura, Kohji; Yamamura, Issei; Zemcov, Michael

2017-02-01

We present near-infrared (0.8-1.8 μm) spectra of 105 bright ({m}J < 10) stars observed with the low-resolution spectrometer on the rocket-borne Cosmic Infrared Background Experiment. As our observations are performed above the Earth's atmosphere, our spectra are free from telluric contamination, which makes them a unique resource for near-infrared spectral calibration. Two-Micron All-Sky Survey photometry information is used to identify cross-matched stars after reduction and extraction of the spectra. We identify the spectral types of the observed stars by comparing them with spectral templates from the Infrared Telescope Facility library. All the observed spectra are consistent with late F to M stellar spectral types, and we identify various infrared absorption lines.

Biomechanical Analysis of Weighted-Ball Exercises for Baseball Pitchers.

PubMed

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

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

Specific Shoulder Pathoanatomy in Semiprofessional Water Polo Players

PubMed Central

Klein, Maria; Tarantino, Ignazio; Warschkow, René; Berger, Claus Joachim; Zdravkovic, Vilijam; Jost, Bernhard; Badulescu, Michael

2014-01-01

Background: Shoulders of throwing and swimming athletes are highly stressed joints that often show structural abnormalities on magnetic resonance imaging (MRI). However, while water polo players exhibit a combination of throwing and swimming movements, a specific pattern of pathological findings has not been described. Purpose: To assess specific MRI abnormalities in shoulders of elite water polo players and to compare these findings with a healthy control group. Study Design: Cross-sectional study; Level of evidence, 3. Methods: After performing a power analysis, volunteers were recruited for this study. Both shoulders of 28 semiprofessional water polo players and 15 healthy volunteers were assessed clinically (based on the Constant score) and had bilateral shoulder MRIs. The shoulders were clustered into 3 groups: 28 throwing and 28 nonthrowing shoulders of water polo athletes and 30 shoulders of healthy control subjects. Results: Twenty-eight male water polo players with an average age of 24 years and 15 healthy subjects (30 shoulders) with an average age of 31 years were examined. Compared with controls, significantly more MRI abnormalities in the water polo players' throwing shoulders could be found in the subscapularis, infraspinatus, and posterior labrum (P = .001, P = .024, and P = .041, respectively). Other structures showed no statistical differences between the 3 groups, including the supraspinatus tendon, which had abnormalities in 36% of throwing versus 32% of nonthrowing shoulders and 33% of control shoulders. All throwing shoulders showed abnormal findings in the MRI, but only 8 (29%) were symptomatic. Conclusion: The shoulders of semiprofessional water polo players demonstrated abnormalities in subscapularis and infraspinatus tendons that were not typical abnormalities for swimmers or throwing athletes. Clinical Relevance: The throwing shoulders of water polo players have specific MRI changes. Clinical symptoms do not correlate with the MRI findings. PMID:26535326

A Sounding Rocket Experiment for the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP)

NASA Astrophysics Data System (ADS)

Kubo, M.; Kano, R.; Kobayashi, K.; Bando, T.; Narukage, N.; Ishikawa, R.; Tsuneta, S.; Katsukawa, Y.; Ishikawa, S.; Suematsu, Y.; Hara, H.; Shimizu, T.; Sakao, T.; Ichimoto, K.; Goto, M.; Holloway, T.; Winebarger, A.; Cirtain, J.; De Pontieu, B.; Casini, R.; Auchère, F.; Trujillo Bueno, J.; Manso Sainz, R.; Belluzzi, L.; Asensio Ramos, A.; Štěpán, J.; Carlsson, M.

2014-10-01

A sounding-rocket experiment called the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is presently under development to measure the linear polarization profiles in the hydrogen Lyman-alpha (Lyα) line at 121.567 nm. CLASP is a vacuum-UV (VUV) spectropolarimeter to aim for first detection of the linear polarizations caused by scattering processes and the Hanle effect in the Lyα line with high accuracy (0.1%). This is a fist step for exploration of magnetic fields in the upper chromosphere and transition region of the Sun. Accurate measurements of the linear polarization signals caused by scattering processes and the Hanle effect in strong UV lines like Lyα are essential to explore with future solar telescopes the strength and structures of the magnetic field in the upper chromosphere and transition region of the Sun. The CLASP proposal has been accepted by NASA in 2012, and the flight is planned in 2015.

Physics of overarm throwing

NASA Astrophysics Data System (ADS)

Cross, Rod

2004-03-01

Measurements are presented of the speed at which objects of different mass can be projected by an overarm throw. Light objects can be thrown faster than heavy objects, although the difference in speed is not as large as one might expect. For a factor of 60 increase in the thrown mass, there was a decrease of only 2.4 in the throw speed. The relatively small change in throw speed is due to the fact that the force that can be applied to a thrown object increases with object mass. Estimates of the muscle forces involved indicate that the increase in force with mass is primarily an inertial rather than a physiological effect. The total kinetic energy of the mass, hand, and the forearm was found to be almost independent of the object mass, and the throw speed is almost independent of the mass of the upper arm.

Russian Rocket Engine Test

NASA Technical Reports Server (NTRS)

1998-01-01

NASA engineers successfully tested a Russian-built rocket engine on November 4, 1998 at the Marshall Space Flight Center (MSFC) Advanced Engine Test Facility, which had been used for testing the Saturn V F-1 engines and Space Shuttle Main engines. The MSFC was under a Space Act Agreement with Lockheed Martin Astronautics of Denver to provide a series of test firings of the Atlas III propulsion system configured with the Russian-designed RD-180 engine. The tests were designed to measure the performance of the Atlas III propulsion system, which included avionics and propellant tanks and lines, and how these components interacted with the RD-180 engine. The RD-180 is powered by kerosene and liquid oxygen, the same fuel mix used in Saturn rockets. The RD-180, the most powerful rocket engine tested at the MSFC since Saturn rocket tests in the 1960s, generated 860,000 pounds of thrust. The test was the first test ever anywhere outside Russia of a Russian designed and built engine.

14 CFR 101.29 - Information requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Information requirements. 101.29 Section... BALLOONS Amateur Rockets § 101.29 Information requirements. (a) Class 2—High-Power Rockets. When a Class 2... must provide the information below on each type of rocket to the FAA at least 45 days before the...

Users manual for program ADMIT: Admittance and pressure transfer function developed for use on a PC computer

NASA Technical Reports Server (NTRS)

Armstrong, Wilbur C.

1992-01-01

The piping in a liquid rocket can assume complex configurations due to multiple tanks, multiple engines, and structures that must be piped around. The capability to handle some of these complex configurations have been incorporated into the ADMIT code. The capability to modify the input on line has been implemented. The configurations allowed include multiple tanks, multiple engines, the splitting of a pipe into unequal segments going to different (or the same) engines. This program will handle the following type elements: straight pipes, bends, inline accumulators, tuned stub accumulators, Helmholtz resonators, parallel resonators, pumps, split pipes, multiple tanks, and multiple engines.

Users manual for program SSFREQ intermediate mode stability curves: Developed for use on a PC computer

NASA Technical Reports Server (NTRS)

Armstrong, Wilbur C.

1992-01-01

The piping in a liquid rocket can assume complex configurations due to multiple tanks, multiple engines, and structures that must be piped around. The capability to handle some of these complex configurations have been incorporated into the SSFREQ code. The capability to modify the input on line has been implemented. The configurations allowed include multiple tanks, multiple engines, the splitting of a pipe into equal segments going to different (or the same) engines. This program will handle the following type elements: straight pipes, bends, inline accumulators, tuned stub accumulators, Helmholtz resonators, parallel resonators, pumps, split pipes, multiple tanks, and multiple engines.

Projectile Motion for Quarterbacks: How to Throw the Perfect Pass

ERIC Educational Resources Information Center

Tomin, Milan; Scipioni, Marco; DeAngelis, Fred

2018-01-01

In the sport of American football, the quarterback (QB) is the player almost always responsible for throwing the ball downfield to an open receiver. That important throw requires him to make a split second decision to launch the ball at the correct speed and angle to guarantee it lands directly into the hands of the receiver. In this paper we…

Is a Basketball Free-Throw Sequence Nonrandom? A Group Exercise for Undergraduate Statistics Students

ERIC Educational Resources Information Center

Adolph, Stephen C.

2007-01-01

I describe a group exercise that I give to my undergraduate biostatistics class. The exercise involves analyzing a series of 200 consecutive basketball free-throw attempts to determine whether there is any evidence for sequential dependence in the probability of making a free-throw. The students are given the exercise before they have learned the…

Verbal instruction for correcting errors versus such instructions plus videotape replay on learning the overhand throw.

PubMed

Kernodle, M W; Johnson, R; Arnold, D R

2001-06-01

The influence of two methods of providing information to women, ages 19 to 22 years who were novices and learning the overhand throw with the nondominant arm, was examined. One group received verbal information on correcting errors, and a second group received the same information immediately prior to viewing a videotaped replay of a just completed throw. Performance was assessed quantitatively with respect to outcome (distance thrown) and qualitatively with respect to throwing form as measured on a 7-point rating scale by judges with a working knowledge of the overhand throw and with respect to throwing mechanics rated by a panel of experts in biomechanics using a scale of Leme and Shambes. Although the treatments led to better learning and performance, there was no significant difference between groups for distance thrown on the Leme and Shambes scale in Sessions 1-6 of 10 trials each on Session 7. The mean rating also indicated increased scores for both groups and better retention at posttest by the group receiving only verbal corrections. These results suggest that information provided by adding videotaped replay may be redundant and unnecessary for those in Sessions 1-6.

Rapid and accurate estimation of release conditions in the javelin throw.

PubMed

Hubbard, M; Alaways, L W

1989-01-01

We have developed a system to measure initial conditions in the javelin throw rapidly enough to be used by the thrower for feedback in performance improvement. The system consists of three subsystems whose main tasks are: (A) acquisition of automatically digitized high speed (200 Hz) video x, y position data for the first 0.1-0.2 s of the javelin flight after release (B) estimation of five javelin release conditions from the x, y position data and (C) graphical presentation to the thrower of these release conditions and a simulation of the subsequent flight together with optimal conditions and flight for the sam release velocity. The estimation scheme relies on a simulation model and is at least an order of magnitude more accurate than previously reported measurements of javelin release conditions. The system provides, for the first time ever in any throwing event, the ability to critique nearly instantly in a precise, quantitative manner the crucial factors in the throw which determine the range. This should be expected to much greater control and consistency of throwing variables by athletes who use system and could even lead to an evolution of new throwing techniques.

A design of experiments test to define critical spray cleaning parameters for Brulin 815 GD and Jettacin cleaners

NASA Technical Reports Server (NTRS)

Keen, Jill M.; Evans, Kurt B.; Schiffman, Robert L.; Deweese, C. Darrell; Prince, Michael E.

1995-01-01

Experimental design testing was conducted to identify critical parameters of an aqueous spray process intended for cleaning solid rocket motor metal components (steel and aluminum). A two-level, six-parameter, fractional factorial matrix was constructed and conducted for two cleaners, Brulin 815 GD and Diversey Jettacin. The matrix parameters included cleaner temperature and concentration, wash density, wash pressure, rinse pressure, and dishwasher type. Other spray parameters: nozzle stand-off, rinse water temperature, wash and rinse time, dry conditions, and type of rinse water (deionized) were held constant. Matrix response testing utilized discriminating bond specimens (fracture energy and tensile adhesion strength) which represent critical production bond lines. Overall, Jettacin spray cleaning was insensitive to the range of conditions tested for all parameters and exhibited bond strengths significantly above the TCA test baseline for all bond lines tested. Brulin 815 was sensitive to cleaning temperature, but produced bond strengths above the TCA test baseline even at the lower temperatures. Ultimately, the experimental design database was utilized to recommend process parameter settings for future aqueous spray cleaning characterization work.

Tilting-filter measurements in dayglow rocket photometry.

PubMed

Schaeffer, R C; Fastie, W G

1972-10-01

A rocket-borne photometer containing two tilting-filter channels for the measurement of the [OI] lambdalambda6300-A and 5577A emission lines in the day airglow is described. The results of one flight substantiate the employment of tilting filters to determine accurate corrections for background continuum and provide reliable height profiles of emission intensity down to approximately 90 km. Discussions on the calibration of the instrument and its baffling against sunlight are also presented.

Advanced Concept

NASA Image and Video Library

2008-03-15

A CONCEPT IMAGE SHOWS THE ARES I CREW LAUNCH VEHICLE DURING ASCENT. ARES I IS AN IN-LINE, TWO-STAGE ROCKET CONFIGURATION TOPED BY THE ORION CREW EXPLORATION VEHICLE AND LAUNCH ABORT SYSTEM. THE ARES I FIRST STAGE IS A SINGLE, FIVE-SEGMENT REUSABLE SOLID ROCKET BOOSTER, DERIVED FROM THE SPACE SHUTTLE. ITS UPPER STAGE IS POWERED BY A J-2X ENGINE. ARES I WILL CARRY THE ORION WITH ITS CRW OF UP TO SIX ASTRONAUTS TO EARTH ORBIT.

Hybrid rocket propellants from lunar material

NASA Astrophysics Data System (ADS)

Sparks, Douglas R.

This paper examines the use of lunar material for hybrid rocket propellants. Liquid oxygen is identified as the primary oxidizer and metals such as aluminum, magnesium, calcium, titanium and silicon are compared as possible fuels. Due to the reduced transportation costs, the use of lunar materials for both oxidizer and fuel will dramatically reduce the cost of a sustained space program. The advantage of hybrid rocket systems over liquid and solid rockets is discussed. It is pointed out that this type of hybrid rocket propellant could also be obtained from asteroidal and planetary soils, thereby facilitating the exploration and industrialization of the inner solar system.

Elbow isokinetic strength characteristics among collegiate baseball players.

PubMed

Laudner, Kevin G; Wilson, James T; Meister, Keith

2012-05-01

To compare the bilateral strength characteristics of the wrist flexors, extensors, pronators, and supinators among baseball players. Cross-sectional. Laboratory. 30 collegiate baseball players with no recent history of upper extremity injury. Bilateral pronation, supination, wrist flexion, and wrist extension peak torque (PT) and peak torque to body weight (PT/BW) strength were measured at speeds of 90 and 180°/second. Paired t-tests showed that the throwing arm of baseball players produced significantly less PT/BW strength for supination at 90°/second compared to the non-throwing arm (P = .001). The throwing arm produced significantly more PT/BW strength for pronation (P = .001) at 180°/second compared to the non-throwing arm. Furthermore, the throwing arm had more PT and PT/BW strength for wrist extension (P < .005) at 180°/second. Conversely, the throwing arm had less PT and PT/BW strength for supination (P < .004) and wrist flexion (P < .004) at 180°/second compared to the non-throwing arm. Significant bilateral strength differences exist in pronation, supination, wrist flexion, and wrist extension among collegiate baseball players. With the steady increase in ulnar collateral ligament injuries of the elbow among baseball players and the proven resistance to valgus force provided by the flexor-pronator mass of the elbow, the results of this study may prove beneficial in the prevention, evaluation, and rehabilitation of such dysfunctions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Examining impulse-variability in overarm throwing.

PubMed

Urbin, M A; Stodden, David; Boros, Rhonda; Shannon, David

2012-01-01

The purpose of this study was to examine variability in overarm throwing velocity and spatial output error at various percentages of maximum to test the prediction of an inverted-U function as predicted by impulse-variability theory and a speed-accuracy trade-off as predicted by Fitts' Law Thirty subjects (16 skilled, 14 unskilled) were instructed to throw a tennis ball at seven percentages of their maximum velocity (40-100%) in random order (9 trials per condition) at a target 30 feet away. Throwing velocity was measured with a radar gun and interpreted as an index of overall systemic power output. Within-subject throwing velocity variability was examined using within-subjects repeated-measures ANOVAs (7 repeated conditions) with built-in polynomial contrasts. Spatial error was analyzed using mixed model regression. Results indicated a quadratic fit with variability in throwing velocity increasing from 40% up to 60%, where it peaked, and then decreasing at each subsequent interval to maximum (p < .001, η2 = .555). There was no linear relationship between speed and accuracy. Overall, these data support the notion of an inverted-U function in overarm throwing velocity variability as both skilled and unskilled subjects approach maximum effort. However, these data do not support the notion of a speed-accuracy trade-off. The consistent demonstration of an inverted-U function associated with systemic power output variability indicates an enhanced capability to regulate aspects of force production and relative timing between segments as individuals approach maximum effort, even in a complex ballistic skill.

Stretch-Induced Reductions in Throwing Performance Are Attenuated by Warm-up Before Exercise.

PubMed

Mascarin, Naryana C; Vancini, Rodrigo L; Lira, Claudio A B; Andrade, Marilia S

2015-05-01

Recent investigations have suggested that static stretching (SS) performed before exercise reduces muscular performance. However, it is yet unknown whether dynamic warm-up exercises performed together with SS may actually minimize the detrimental acute effects of stretching on muscular performance. This study aimed to assess the effects of static shoulder stretching exercises, dynamic warm-up exercises, or both together, on muscular performance evaluated by ball throwing. Twenty-one female handball players (age: 16.2 ± 1.0 years [range: 14-18 years], height: 167.0 ± 10.0 cm [range: 158-179 cm], and body mass: 63.3 ± 7.6 kg [range: 50.4-77.4 kg]) performed SS, dynamic warm-up exercises or both, targeting the muscles of the upper limbs. Thereafter, medicine ball throwing distance and handball ball throwing speed tests were performed. Static stretching performed before the medicine ball throwing test reduced performance when compared with the warm-up exercises (95% confidence interval [CI] = 0.02-0.17, p ≤ 0.05, effect size [ES] = 0.34). When a warm-up exercise routine was added to SS, the detrimental effects of SS were abolished (95% CI = -0.01 to 0.18, p > 0.05, ES = 0.31). The throwing speed was the same over the 3 conditions. In conclusion, warm-up exercises performed together with SS abolished the impairment in medicine ball throwing distance. We recommend that athletes perform warm-up exercises together with SS before activity to avoid detrimental effects on muscle strength.

Performance potential of gas-core and fusion rockets - A mission applications survey.

NASA Technical Reports Server (NTRS)

Fishbach, L. H.; Willis, E. A., Jr.

1971-01-01

This paper reports an evaluation of the performance potential of five nuclear rocket engines for four mission classes. These engines are: the regeneratively cooled gas-core nuclear rocket; the light bulb gas-core nuclear rocket; the space-radiator cooled gas-core nuclear rocket; the fusion rocket; and an advanced solid-core nuclear rocket which is included for comparison. The missions considered are: earth-to-orbit launch; near-earth space missions; close interplanetary missions; and distant interplanetary missions. For each of these missions, the capabilities of each rocket engine type are compared in terms of payload ratio for the earth launch mission or by the initial vehicle mass in earth orbit for space missions (a measure of initial cost). Other factors which might determine the engine choice are discussed. It is shown that a 60 day manned round trip to Mars is conceivable.-

Translations on Eastern Europe, Political, Sociological and Military Affairs, Number 1601

DTIC Science & Technology

1978-10-25

every house has lots of fishing gear, they all fish, throw out their lines and pull them in, and cry when there are no fish. Yet still we ail eat...every day. Everyone pulls out a kilogram a day at least. And what about poachers? There are enough of them here too. They can hardly wait for my...picked the lemons. Who else would do that but the local people, to pull such a prank." The mother would not hear of such a thing: "What do you

14 CFR Appendix E to Part 25 - Appendix E to Part 25

Code of Federal Regulations, 2013 CFR

2013-01-01

... certificated takeoff and landing weights of an airplane equipped with a type-certificated standby power rocket engine may obtain an increase as specified in paragraph (b) if— (1) The installation of the rocket engine has been approved and it has been established by flight test that the rocket engine and its controls...

14 CFR Appendix E to Part 25 - Appendix E to Part 25

Code of Federal Regulations, 2011 CFR

2011-01-01

... certificated takeoff and landing weights of an airplane equipped with a type-certificated standby power rocket engine may obtain an increase as specified in paragraph (b) if— (1) The installation of the rocket engine has been approved and it has been established by flight test that the rocket engine and its controls...

14 CFR Appendix E to Part 25 - Appendix E to Part 25

Code of Federal Regulations, 2014 CFR

2014-01-01

... certificated takeoff and landing weights of an airplane equipped with a type-certificated standby power rocket engine may obtain an increase as specified in paragraph (b) if— (1) The installation of the rocket engine has been approved and it has been established by flight test that the rocket engine and its controls...

14 CFR Appendix E to Part 25 - Appendix E to Part 25

Code of Federal Regulations, 2012 CFR

2012-01-01

... certificated takeoff and landing weights of an airplane equipped with a type-certificated standby power rocket engine may obtain an increase as specified in paragraph (b) if— (1) The installation of the rocket engine has been approved and it has been established by flight test that the rocket engine and its controls...

14 CFR Appendix E to Part 25 - Appendix E to Part 25

Code of Federal Regulations, 2010 CFR

2010-01-01

... certificated takeoff and landing weights of an airplane equipped with a type-certificated standby power rocket engine may obtain an increase as specified in paragraph (b) if— (1) The installation of the rocket engine has been approved and it has been established by flight test that the rocket engine and its controls...

Predictive Ability of the Medicine Ball Chest Throw and Vertical Jump Tests for Determining Muscular Strength and Power in Adolescents

ERIC Educational Resources Information Center

Hackett, Daniel A.; Davies, Timothy B.; Ibel, Denis; Cobley, Stephen; Sanders, Ross

2018-01-01

This study examined the predictive ability of the medicine ball chest throw and vertical jump for muscular strength and power in adolescents. One hundred and ninety adolescents participated in this study. Participants performed trials of the medicine ball chest throw and vertical jump, with vertical jump peak power calculated via an estimation…

Effects of 4-Week Training Intervention with Unknown Loads on Power Output Performance and Throwing Velocity in Junior Team Handball Players

PubMed Central

Sabido, Rafael; Hernández-Davó, Jose Luis; Botella, Javier; Moya, Manuel

2016-01-01

Purpose To compare the effect of 4-week unknown vs known loads strength training intervention on power output performance and throwing velocity in junior team handball players. Methods Twenty-eight junior team-handball players (17.2 ± 0.6 years, 1.79 ± 0.07 m, 75.6 ± 9.4 kg)were divided into two groups (unknown loads: UL; known loads: KL). Both groups performed two sessions weekly consisting of four sets of six repetitions of the bench press throw exercise, using the 30%, 50% and 70% of subjects’ individual 1 repetition maximum (1RM). In each set, two repetitions with each load were performed, but the order of the loads was randomised. In the KL group, researchers told the subjects the load to mobilise prior each repetition, while in the UL group, researchers did not provide any information. Maximal dynamic strength (1RM bench press), power output (with 30, 50 and 70% of 1RM) and throwing velocity (7 m standing throw and 9 m jumping throw) were assessed pre- and post-training intervention. Results Both UL and KL group improved similarly their 1RM bench press as well as mean and peak power with all loads. There were significant improvements in power developed in all the early time intervals measured (150 ms) with the three loads (30, 50, 70% 1RM) in the UL group, while KL only improved with 30% 1RM (all the time intervals) and with 70% 1RM (at certain time intervals). Only the UL group improved throwing velocity in both standing (4.7%) and jumping (5.3%) throw (p > 0.05). Conclusions The use of unknown loads has led to greater gains in power output in the early time intervals as well as to increases in throwing velocity compared with known loads. Therefore unknown loads are of significant practical use to increase both strength and in-field performance in a short period of training. PMID:27310598

A Content Analysis of 'O' Level Papers on Imperial and Commonwealth History Set by Two GCE Examination Boards.

ERIC Educational Resources Information Center

Inglis, W. F. J.

1979-01-01

This study sought to determine what types of history were emphasized by the Examination Boards and thus to throw light on the experience in history which was gained by candidates for these exams. A bias toward the political history of the imperial power was found. (Author/SJL)

[The Throwing Shoulder].

PubMed

Wieser, Karl; Gerber, Christian; Meyer, Dominik C

2016-02-03

Repetitive top-performance of overhead athletes induces a tremendous stress for the throwing shoulder. Throwers reach rotational speed of their arm of more than 7000°/s with joint compression and distraction forces of more than 1000 N. This performance is tributary to adaption of the shoulder muscles and the joint itself. These adaptions may, however lead to two specific problems of the throwing shoulder: 1. The posterosuperior internal impingement of the rotator cuff and labrum between glenoid and humeral head during late cooking phase; 2. A decreased internal rotation of the glenohumeral joint (GIRD) with compensatory problems of the scapula-stabilizing muscles. Precise analysis of kinematics and pathomechanics aims to improve understanding and treatment of those specific problems of the throwing shoulder.

Muscle fiber type, Achilles tendon length, potentiation, and running economy.

PubMed

Hunter, Gary R; McCarthy, John P; Carter, Stephen J; Bamman, Marcas M; Gaddy, Emily S; Fisher, Gordon; Katsoulis, Kostantina; Plaisance, Eric P; Newcomer, Bradley R

2015-05-01

The purpose of this investigation was to develop a potential model for how muscle fiber type, Achilles tendon length, stretch-shortening cycle potentiation (SSCP), and leg strength interact with running economy. Twenty trained male distance runners 24-40 years of age served as subjects. Running economy (net oxygen uptake) was measured while running on a treadmill. Leg press SSCP(force) and SSCP(velocity) were determined by measuring the difference in velocity between a static leg press throw and a countermovement leg press throw. Vertical jump SSCP was determined by measuring the difference in jump height between a static jump and a drop jump from a 20.3-cm bench. Tendon length was measured by magnetic resonance imaging, and muscle fiber type was made from a vastus lateralis muscle biopsy. Type IIx muscle fiber percent (r = 0.70, p < 0.001) and leg strength (r = 0.95, p < 0.001) were positively and independently related to late eccentric force development. Achilles tendon length (r = 0.42, p ≤ 0.05) and late eccentric force during stretch-shortening cycle (r = 0.76, p < 0.001) were independently related to SSCP(force). SSCP(force) was related to SSCP(velocity), which in turn was related to running economy (r = 0.61, p < 0.01). These results suggest that longer Achilles tendon length, type II fiber, and muscular leg strength may enhance the potential for SSCP, running economy, and physiological effort while running.

An introduction to the water recovery x-ray rocket

NASA Astrophysics Data System (ADS)

Miles, Drew M.; McEntaffer, Randall L.; Schultz, Ted B.; Donovan, Benjamin D.; Tutt, James H.; Yastishock, Daniel; Steiner, Tyler; Hillman, Christopher R.; McCoy, Jake A.; Wages, Mitchell; Hull, Sam; Falcone, Abe; Burrows, David N.; Chattopadhyay, Tanmoy; Anderson, Tyler; McQuaide, Maria

2017-08-01

The Water Recovery X-ray Rocket (WRXR) is a sounding rocket payload that will launch from the Kwajalein Atoll in April 2018 and seeks to be the first astrophysics sounding rocket payload to be water recovered by NASA. WRXR's primary instrument is a grating spectrometer that consists of a mechanical collimator, X-ray reflection gratings, grazing-incidence mirrors, and a hybrid CMOS detector. The instrument will obtain a spectrum of the diffuse soft X-ray emission from the northern part of the Vela supernova remnant and is optimized for 3rd and 4th order OVII emission. Utilizing a field of view of 3.25° × 3.25° and resolving power of λ/δλ ≍40-50 in the lines of interest, the WRXR spectrometer aims to achieve the most highly-resolved spectrum of Vela's diffuse soft X-ray emission. This paper presents introductions to the payload and the science target.

Around Marshall

NASA Image and Video Library

1998-11-04

NASA engineers successfully tested a Russian-built rocket engine on November 4, 1998 at the Marshall Space Flight Center (MSFC) Advanced Engine Test Facility, which had been used for testing the Saturn V F-1 engines and Space Shuttle Main engines. The MSFC was under a Space Act Agreement with Lockheed Martin Astronautics of Denver to provide a series of test firings of the Atlas III propulsion system configured with the Russian-designed RD-180 engine. The tests were designed to measure the performance of the Atlas III propulsion system, which included avionics and propellant tanks and lines, and how these components interacted with the RD-180 engine. The RD-180 is powered by kerosene and liquid oxygen, the same fuel mix used in Saturn rockets. The RD-180, the most powerful rocket engine tested at the MSFC since Saturn rocket tests in the 1960s, generated 860,000 pounds of thrust.

Guessing imagined and live chance events: adults behave like children with live events.

PubMed

Robinson, E J; Pendle, J E C; Rowley, M G; Beck, S R; McColgan, K L T

2009-11-01

An established finding is that adults prefer to guess before rather than after a chance event has happened. This is interpreted in terms of aversion to guessing when relatively incompetent: After throwing, the fall could be known. Adults (N=71, mean age 18;11, N=28, mean age 48;0) showed this preference with imagined die-throwing as in the published studies. With live die-throwing, children (N=64, aged 6 and 8 years; N=50, aged 5 and 6 years) and 15-year-olds (N=93, 46) showed the opposite preference, as did 17 adults. Seventeen-year-olds (N=82) were more likely to prefer to guess after throwing with live rather than imagined die-throwing. Reliance on imagined situations in the literature on decision-making under uncertainty ignores the possibility that adults imagine inaccurately how they would really feel: After a real die has been thrown, adults, like children, may feel there is less ambiguity about the outcome.

Examining Impulse-Variability Theory and the Speed-Accuracy Trade-Off in Children's Overarm Throwing Performance.

PubMed

Molina, Sergio L; Stodden, David F

2018-04-01

This study examined variability in throwing speed and spatial error to test the prediction of an inverted-U function (i.e., impulse-variability [IV] theory) and the speed-accuracy trade-off. Forty-five 9- to 11-year-old children were instructed to throw at a specified percentage of maximum speed (45%, 65%, 85%, and 100%) and hit the wall target. Results indicated no statistically significant differences in variable error across the target conditions (p = .72), failing to support the inverted-U hypothesis. Spatial accuracy results indicated no statistically significant differences with mean radial error (p = .18), centroid radial error (p = .13), and bivariate variable error (p = .08) also failing to support the speed-accuracy trade-off in overarm throwing. As neither throwing performance variability nor accuracy changed across percentages of maximum speed in this sample of children as well as in a previous adult sample, current policy and practices of practitioners may need to be reevaluated.

Heat exchanger and method of making. [rocket lining

NASA Technical Reports Server (NTRS)

Fortini, A.; Kazaroff, J. M. (Inventor)

1980-01-01

A heat exchange of increased effectiveness is disclosed. A porous metal matrix is disposed in a metal chamber or between walls through which a heat-transfer fluid is directed. The porous metal matrix has internal bonds and is bonded to the chamber in order to remove all thermal contact resistance within the composite structure. Utilization of the invention in a rocket chamber is disclosed as a specific use. Also disclosed is a method of constructing the heat exchanger.

Low-altitude acceleration of auroral electrons during breakup observed by a mother-daughter rocket

NASA Technical Reports Server (NTRS)

Johnstone, A. D.; Davis, T. N.

1974-01-01

By the use of a mother-daughter rocket combination and ground-based observations with television, time and space variations are resolved in particle measurements in breakup aurora. The spectral variations measured during a temporal variation in the aurora can be explained by a nearly uniform acceleration of all the electrons such as would be caused by an electric potential drop along the magnetic field lines. Many other explanations can be eliminated.

Rocket engine exhaust plume diagnostics and health monitoring/management during ground testing

NASA Technical Reports Server (NTRS)

Chenevert, D. J.; Meeks, G. R.; Woods, E. G.; Huseonica, H. F.

1992-01-01

The current status of a rocket exhaust plume diagnostics program sponsored by NASA is reviewed. The near-term objective of the program is to enhance test operation efficiency and to provide for safe cutoff of rocket engines prior to incipient failure, thereby avoiding the destruction of the engine and the test complex and preventing delays in the national space program. NASA programs that will benefit from the nonintrusive remote sensed rocket plume diagnostics and related vehicle health management and nonintrusive measurement program are Space Shuttle Main Engine, National Launch System, National Aero-Space Plane, Space Exploration Initiative, Advanced Solid Rocket Motor, and Space Station Freedom. The role of emission spectrometry and other types of remote sensing in rocket plume diagnostics is discussed.

A Flight Demonstration of Plasma Rocket Propulsion

NASA Technical Reports Server (NTRS)

Petro, Andrew

1999-01-01

The Advanced Space Propulsion Laboratory at the Johnson Space Center has been engaged in the development of a magneto-plasma rocket for several years. This type of rocket could be used in the future to propel interplanetary spacecraft. One advantageous feature of this rocket concept is the ability to vary its specific impulse so that it can be operated in a mode which maximizes propellant efficiency or a mode which maximizes thrust. This presentation will describe a proposed flight experiment in which a simple version of the rocket will be tested in space. In addition to the plasma rocket, the flight experiment will also demonstrate the use of a superconducting electromagnet, extensive use of heat pipes, and possibly the transfer of cryogenic propellant in space.

Design and analysis of compact MMIC switches utilising GaAs pHEMTs in 3D multilayer technology

NASA Astrophysics Data System (ADS)

Haris, Norshakila; Kyabaggu, Peter B. K.; Alim, Mohammad A.; Rezazadeh, Ali A.

2017-05-01

In this paper, we demonstrate for the first time the implementation of three-dimensional multilayer technology on GaAs-based pseudomorphic high electron mobility transistor (pHEMT) switches. Two types of pHEMT switches are considered, namely single-pole single-throw (SPST) and single-pole double-throw (SPDT). The design and analysis of the devices are demonstrated first through a simulation of the industry-recognised standard model, TriQuint’s Own Model—Level 3, developed by TriQuint Semiconductor, Inc. From the simulation analysis, three optimised SPST and SPDT pHEMT switches which can address applications ranging from L to X bands, are fabricated and tested. The performance of the pHEMT switches using multilayer technology are comparable to those of the current state-of-the-art pHEMT switches, while simultaneously offering compact circuits with the advantages of integration with other MMIC components.

Learning to throw on a rotating carousel: recalibration based on limb dynamics and projectile kinematics.

PubMed

Bruggeman, Hugo; Pick, Herbert L; Rieser, John J

2005-05-01

Skilled actions exhibit adjustment in calibration to bring about their goals. The sought-after calibrations change as a function of the environmental situation that stages the actions. In these experiments participants sat on one side of a rotating carousel and threw beanbags underhanded at a target fixed on the opposite side. Logically, aimed throwing in this situation involves adjustment to fit changes in limb dynamics (originating from Coriolis forces) and changes in perceived projectile kinematics (originating from the tangential velocity of thrower and target). We studied whether such adjustment involved one or multiple components of recalibration. An initial experiment showed that exposure to rotation while throwing beanbags produced a robust recalibration in the direction of underhanded throws as manifest in throwing at stationary targets from a stationary position. Following some initial decay this recalibration persisted and approached an asymptote. Subsequent experiments suggested two independent components of recalibration. One is based on limb dynamics and accounts for the initial decay. The other is based on the perceived projectile kinematics and accounts for the stable change in throwing direction. These results raised the question of how multiple components of recalibration of an action are related. We propose that movement components are independent and calibrated separately at different levels in the organization of an action.

Brain lateralisation and motor learning: selective effects of dominant and non-dominant hand practice on the early acquisition of throwing skills.

PubMed

Stöckel, Tino; Weigelt, Matthias

2012-01-01

Findings from neurosciences indicate that the two brain hemispheres are specialised for the processing of distinct movement features. How this knowledge can be useful in motor learning remains unclear. Two experiments were conducted to investigate the influence of initial practice with the dominant vs non-dominant hand on the acquisition of novel throwing skills. Within a transfer design two groups practised a novel motor task with the same amount of practice on each hand, but in opposite hand-order. In Experiment 1, participants acquired the position throw in basketball, which places high demands on throwing accuracy. Participants practising this task with their non-dominant hand first, before changing to the dominant hand, showed better skill acquisition than participants practising in opposite order. In Experiment 2 participants learned the overarm throw in team handball, which requires great throwing strength. Participants initially practising with their dominant hand benefited more from practice than participants beginning with their non-dominant hand. These results indicate that spatial accuracy tasks are learned better after initial practice with the non-dominant hand, whereas initial practice with the dominant hand is more efficient for maximum force production tasks. The effects are discussed in terms of brain lateralisation and bilateral practice schedules.

The Development of Humeral Retrotorsion and Its Relationship to Throwing Sports.

PubMed

Greenberg, Elliot M; Fernandez-Fernandez, Alicia; Lawrence, J Todd R; McClure, Philip

2015-01-01

Several investigations have noted that throwing athletes exhibit a more posteriorly oriented humeral head (humeral retrotorsion) in the dominant arm. This asymmetry is believed to represent an adaptive response to the stress of throwing that occurs during childhood. The significance of this alteration and factors that affect its development are currently not clear. Basic science, research studies, and review articles were searched through PubMed with search terms including humeral torsion, humeral retrotorsion, and with 1 of the following: pediatric, adult, baseball, pitching, shoulder, and range of motion. The references from each article were reviewed for further inclusion. This review included articles through March 2015. Clinical review. Level 4. The throwing motion creates stressors that result in bony adaptations that occur while skeletally immature. These osseous changes likely contribute to the observed shift in the arc of rotational range of motion noted in throwing athletes and may play a protective role against injury. However, too much or too little retrotorsion may predispose the shoulder to injury. The degree of "optimal" humeral retrotorsion and factors that influence its development are not fully understood. Evidence supports the assertion that the throwing motion creates stressors that alter bony anatomy while young. It is important to determine what specific factors affect this adaptation and its relationship to injury. © 2015 The Author(s).

Proprioception and throwing accuracy in the dominant shoulder after cryotherapy.

PubMed

Wassinger, Craig A; Myers, Joseph B; Gatti, Joseph M; Conley, Kevin M; Lephart, Scott M

2007-01-01

Application of cryotherapy modalities is common after acute shoulder injury and as part of rehabilitation. During athletic events, athletes may return to play after this treatment. The effects of cryotherapy on dominant shoulder proprioception have been assessed, yet the effects on throwing performance are unknown. To determine the effects of a cryotherapy application on shoulder proprioception and throwing accuracy. Single-group, pretest-posttest control session design. University-based biomechanics laboratory. Healthy college-aged subjects (n = 22). Twenty-minute ice pack application to the dominant shoulder. Active joint position replication, path of joint motion replication, and the Functional Throwing Performance Index. Subjects demonstrated significant increases in deviation for path of joint motion replication when moving from 90 degrees of abduction with 90 degrees of external rotation to 20 degrees of flexion with neutral shoulder rotation after ice pack application. Also, subjects exhibited a decrease in Functional Throwing Performance Index after cryotherapy application. No differences were found in subjects for active joint position replication after cryotherapy application. Proprioception and throwing accuracy were decreased after ice pack application to the shoulder. It is important that clinicians understand the deficits that occur after cryotherapy, as this modality is commonly used following acute injury and during rehabilitation. This information should also be considered when attempting to return an athlete to play after treatment.

Biomechanics of increased spin velocity of flying discs during forehand throws by skilled and unskilled throwers.

PubMed

Sasakawa, Kei; Umegaki, Koji; Sakurai, Shinji

2018-04-01

We aimed to assess the relationship between throwing distance and kinematic release parameters of the flying disc in unskilled throwers, and to assess the relationship between kinetic variables acting on flying discs and the change in spin velocity during long forehand throws by skilled and unskilled throwers. Ten skilled and eleven unskilled throwers performed throws at maximum effort. Reflective marker positions on the disc and body were recorded with a 3D motion capture system during the throws to derive kinematic variables of a disc and kinetic variables acting on the disc. The analysis interval was from maximum external shoulder rotation to disc release. Significant correlations were observed between the throwing distance and spin velocity in skilled (r = 0.722, P < 0.05) and unskilled throwers (r = 0.794, P < 0.01), between the change in spin velocity and the angular impulse of moments of force, in unskilled throwers (r = 0.703, P < 0.05), and between the change in spin velocity and the angular impulse of torque among skilled throwers (r = 0.680, P < 0.01). Therefore, a strategy for increasing spin velocity in unskilled throwers could be used to generate a larger torque, similar to that observed in skilled throwers.

2. Credit GE. Photographic copy of photograph, refractory brick lining ...

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

2. Credit GE. Photographic copy of photograph, refractory brick lining being laid in Test Stand 'A' flame pit to protect concrete from heat of rocket engine flames. (JPL negative no. 383-764, 8 March 1945) - Jet Propulsion Laboratory Edwards Facility, Test Stand A, Edwards Air Force Base, Boron, Kern County, CA

Cracking Codes & Launching Rockets

ERIC Educational Resources Information Center

Paoletti, Teo J.

2013-01-01

To engage students, many teachers wish to connect the mathematics they are teaching to other branches of mathematics or to real-world applications. The lesson presented in this article, which uses the algebraic skill of finding the equation of a line between two points and the geometric axiom that any two points define a line, does both. A…

Proposed rocket experiments to measure the profile and intensity of the solar He1584A resonance line

NASA Technical Reports Server (NTRS)

Judge, D. L.

1978-01-01

The intensity and profile of the helium resonance line at 584 A from the entire disc of the sun was investigated using a rocket-borne helium-filled spectrometer and a curve of growth technique. The line profile was found to be accurately represented by a Gaussian profile with full width at half maximum of 122 plus or minus 10m A while the integrated intensity was measured to be (2.6 plus or minus 1.3) x 10 to the 9th power/photons sec sq cm at solar levels of F sub 10.7 = 90.8 x 10 to the minus 22th power/sq m H sub z and R sub z = 27. The measured linewidth is in good agreement with previous spectrographic measurement but the integrated intensity is larger than most previous photoelectric measurements. However, the derived line center flux of (2.0 plus or minus 1.0) x 10 to the 10th power/photons sec sq cm A is in good agreement with values inferred from airglow measurements.

Differences in humeral retroversion in dominant and nondominant sides of young baseball players.

PubMed

Kurokawa, Daisuke; Yamamoto, Nobuyuki; Ishikawa, Hiroaki; Nagamoto, Hideaki; Takahashi, Hiroyuki; Muraki, Takayuki; Tanaka, Minoru; Sato, Katsumi; Itoi, Eiji

2017-06-01

The relationship between the disabled throwing shoulder and humeral retroversion has recently attracted a great deal of attention. However, none of the previous studies clarified when the side-to-side difference of humeral retroversion in young baseball players would start. This study aimed to clarify when the difference of humeral retroversion in the dominant and nondominant sides appeared in baseball players. The bicipital-forearm angle in bilateral shoulders of 172 elementary school baseball players was measured by ultrasound. The bicipital-forearm angle was defined as an angle between the perpendicular line to the bicipital groove and the ulnar long axis with the elbow flexed at 90°. The correlation between the bicipital-forearm angle and the grade and the difference of the bicipital-forearm angle between the dominant and nondominant sides were analyzed. In the nondominant shoulders, the bicipital-forearm angle increased with the grade in school (r = 0.32, P < .0001), but this was not observed in the dominant shoulders. In the fourth to sixth graders, the bicipital-forearm angles were significantly smaller in the dominant shoulders than in the nondominant shoulders. Our findings indicated that humeral retroversion decreased with age in the nonthrowing side but not in the throwing side and that the side-to-side difference of humeral retroversion in the baseball players became obvious from the fourth grade. We assume that the repetitive throwing motion restricts the physiologic humeral derotation process and the difference became apparent from the fourth grade when the growth spurt begins in boys. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

CAN UPPER EXTREMITY FUNCTIONAL TESTS PREDICT THE SOFTBALL THROW FOR DISTANCE: A PREDICTIVE VALIDITY INVESTIGATION

PubMed Central

Hanney, William J.; Kolber, Morey J.; Davies, George J.; Riemann, Bryan

2011-01-01

Introduction: Understanding the relationships between performance tests and sport activity is important to the rehabilitation specialist. The purpose of this study was two- fold: 1) To identify if relationships exist between tests of upper body strength and power (Single Arm Seated Shot Put, Timed Push-Up, Timed Modified Pull-Up, and The Davies Closed Kinetic Chain Upper Extremity Stability Test, and the softball throw for distance), 2) To determine which variable or group of variables best predicts the performance of a sport specific task (the softball throw for distance). Methods: One hundred eighty subjects (111 females and 69 males, aged 18-45 years) performed the 5 upper extremity tests. The Pearson product moment correlation and a stepwise regression were used to determine whether relationships existed between performance on the tests and which upper extremity test result best explained the performance on the softball throw for distance. Results: There were significant correlations (r=.33 to r=.70, p=0.001) between performance on all of the tests. The modified pull-up test was the best predictor of the performance on the softball throw for distance (r2= 48.7), explaining 48.7% of variation in performance. When weight, height, and age were added to the regression equation the r2 values increased to 64.5, 66.2, and 67.5 respectively. Conclusion: The results of this study indicate that several upper extremity tests demonstrate significant relationships with one another and with the softball throw for distance. The modified pull up test was the best predictor of performance on the softball throw for distance. PMID:21712942

Motion analysis of throwing Boccia balls in children with cerebral palsy.

PubMed

Huang, Po-Chang; Pan, Po-Jung; Ou, Yu-Chih; Yu, Yi-Chen; Tsai, Yung-Shen

2014-02-01

Boccia is a sport suitable for children with cerebral palsy (CP). Throwing Boccia balls requires upper extremity and torso coordination. This study investigated the differences between children with CP and normally developed children regarding throwing patterns of Boccia balls. Thirteen children with bilateral spastic CP and 20 normally developed children participated in this study. The tests in this study were a pediatric reach test and throwing of Boccia balls. A 3D electromagnetic motion tracking system and a force plate were synchronized to record and analyze biomechanical parameters of throwing Boccia balls. The results of the pediatric reach test for participants with CP were significantly worse than those for normally developed participants. The 2 groups of participants did not significantly differ regarding the distance between a thrown Boccia ball and a target ball (jack). Participants with CP demonstrated significantly longer movement duration, smaller amplitude of elbow movement, greater amplitudes of shoulder abduction and flexion, slower maximal velocity of torso flexion and the linear velocity of moving the wrist joint forward, faster maximal velocity of head flexion, and smaller sway ratio compared with normally developed participants when throwing Boccia balls. Participants with CP seemed to mainly use head and shoulder movements to bring the Boccia balls forward with limited torso movement. Normally developed participants brought the Boccia ball forward with faster torso and greater elbow movement while stabilizing head and shoulder movements. Nevertheless, participants with CP did not demonstrate significantly worse performance in the throwing accuracy of Boccia balls. Copyright © 2013 Elsevier Ltd. All rights reserved.

Factors Modulating Post-Activation Potentiation of Jump, Sprint, Throw, and Upper-Body Ballistic Performances: A Systematic Review with Meta-Analysis.

PubMed

Seitz, Laurent B; Haff, G Gregory

2016-02-01

Although post-activation potentiation (PAP) has been extensively examined following the completion of a conditioning activity (CA), the precise effects on subsequent jump, sprint, throw, and upper-body ballistic performances and the factors modulating these effects have yet to be determined. Moreover, weaker and stronger individuals seem to exhibit different PAP responses; however, how they respond to the different components of a strength-power-potentiation complex remains to be elucidated. This meta-analysis determined (1) the effect of performing a CA on subsequent jump, sprint, throw, and upper-body ballistic performances; (2) the influence of different types of CA, squat depths during the CA, rest intervals, volumes of CA, and loads during the CA on PAP; and (3) how individuals of different strength levels respond to these various strength-power-potentiation complex components. A computerized search was conducted in ADONIS, ERIC, SPORTDiscus, EBSCOhost, Google Scholar, MEDLINE, and PubMed databases up to March 2015. The analysis comprised 47 studies and 135 groups of participants for a total of 1954 participants. The PAP effect is small for jump (effect size [ES] = 0.29), throw (ES = 0.26), and upper-body ballistic (ES = 0.23) performance activities, and moderate for sprint (ES = 0.51) performance activity. A larger PAP effect is observed among stronger individuals and those with more experience in resistance training. Plyometric (ES = 0.47) CAs induce a slightly larger PAP effect than traditional high-intensity (ES = 0.41), traditional moderate-intensity (ES = 0.19), and maximal isometric (ES = -0.09) CAs, and a greater effect after shallower (ES = 0.58) versus deeper (ES = 0.25) squat CAs, longer (ES = 0.44 and 0.49) versus shorter (ES = 0.17) recovery intervals, multiple- (ES = 0.69) versus single- (ES = 0.24) set CAs, and repetition maximum (RM) (ES = 0.51) versus sub-maximal (ES = 0.34) loads during the CA. It is noteworthy that a greater PAP effect can be realized earlier after a plyometric CA than with traditional high- and moderate-intensity CAs. Additionally, shorter recovery intervals, single-set CAs, and RM CAs are more effective at inducing PAP in stronger individuals, while weaker individuals respond better to longer recovery intervals, multiple-set CAs, and sub-maximal CAs. Finally, both weaker and stronger individuals express greater PAP after shallower squat CAs. Performing a CA elicits small PAP effects for jump, throw, and upper-body ballistic performance activities, and a moderate effect for sprint performance activity. The level of potentiation is dependent on the individual's level of strength and resistance training experience, the type of CA, the depth of the squat when this exercise is employed to elicit PAP, the rest period between the CA and subsequent performance, the number of set(s) of the CA, and the type of load used during the CA. Finally, some components of the strength-power-potentiation complex modulate the PAP response of weaker and stronger individuals in a different way.

Low-temperature Ignition-delay Characteristics of Several Rocket Fuels with Mixed Acid in Modified Open-cup-type Apparatus

NASA Technical Reports Server (NTRS)

Miller, Riley O

1950-01-01

Summaries of low-temperature self-ignition data of various rocket fuels with mixed acid (nitric plus sulfuric) are presented. Several fuels are shown to have shorter ignition-delay intervals and less variation in delay intervals at moderate and sub-zero temperatures than crude N-ethylaniline (monoethylaniline),a rocket fuel in current use.

Kinematic Analysis of Javelin Throw Performed by Wheelchair Athletes of Different Functional Classes

PubMed Central

Chow, John W.; Kuenster, Ann F.; Lim, Young-tae

2003-01-01

The purpose of this study was to identify those kinematic characteristics that are most closely related to the functional classification of a wheelchair athlete and measured distance of a javelin throw. Two S-VHS camcorders (60 field·s-1) were used to record the performance of 15 males of different classes. Each subject performed 6-10 throws and the best two legal throws from each subject were selected for analysis. Three-dimensional kinematics of the javelin and upper body segments at the instant of release and during the throw (delivery) were determined. The selection of kinematic parameters that were analyzed in this study was based on a javelin throw model showing the factors that determine the measured distance of a throw. The average of two throws for each subject was used to compute Spearman rank correlation coefficients between selected parameters and measured distance, and between selected parameters and the functional classification. The speeds and angles of the javelin at release, ranged from 9.1 to 14.7 m·s-1 and 29.6 to 35.8°, respectively, were smaller than those exhibited by elite male able-bodied throwers. As expected, the speed of the javelin at release was significantly correlated to both the classification (p<0.01) and measured distance (p<0.001). Of the segmental kinematic parameters, significant correlations were found between the trunk inclination at release and classification and between the angular speed at release and measured distance (p<0.01 for both). The angular speed of the shoulder girdle at release and the average angular speeds of the shoulder girdle during the delivery were significantly correlated to both the classification and measured distance (p<0.05). The results indicate that shoulder girdle movement during the delivery is an important determinant of classification and measured distance. PMID:24616609

Osteochondritis Dissecans of the Glenoid in a Major League Baseball Prospect: A Case Report.

PubMed

Grau, Luis Carlos; Jose, Jean; Sama, Andrew Joseph; Baraga, Michael Gerald

2016-01-01

A 16-year-old Major League Baseball prospect presented with persistent shoulder pain associated with throwing. Magnetic resonance imaging (MRI) demonstrated a large osteochondritis dissecans lesion in the posterosuperior aspect of the glenoid. The patient was restricted from throwing and underwent therapy to improve range of motion and throwing mechanics. Eight months after initiating nonoperative treatment, an MRI arthrogram demonstrated a healed lesion. At follow-up 2 years after treatment, full relief of symptoms had persisted. Osteochondritis dissecans lesions of the glenoid are extremely rare, but have the potential to heal in overhead-throwing athletes. To our knowledge, this is the only case reported in the literature that demonstrates a healed osteochondritis dissecans lesion of the glenoid following nonoperative treatment.

The environmental impact of the use of large wind turbines

NASA Astrophysics Data System (ADS)

Manning, P. T.

The existing data base on the environmental impact of large wind energy conversion systems (WECS) is explored. The maximum blade throw distance has been calculated at 850 m, with a 5% probability of more than 300 m. Good design and inspection procedures reduce the risk. Ice throw can be prevented by aircraft deicing techniques, but detectors are still necessary. TV interference is ameliorated by the use of composite blades and directional antennas, by relocating the nearst transmission or relay station, or by introduction of cable TV. Microwave transmission effects can be avoided by careful siting of WECS in a favorable line of sight whenever within 1 km of a transmitter. Visual impact studies have produced few adverse opinions. Noise has not proved an intractable problem, although 30 dB levels have been exceeded 2100 m downwind of the Mod 2 WECS. Further studies are necessary on the effects of heightened ground turbulence produced by large WECS. It is expected that few birds will be harmed by slowly rotating blades in the birds' natural domain, a projection confirmed by sporadic studies. Finally, aircraft collisions are regarded as unlikely and actual land use, mostly confined to rural areas, is minimal.

New instrumentation technologies for testing the bonding of sensors to solid materials

NASA Technical Reports Server (NTRS)

Hashemian, H. M.; Shell, C. S.; Jones, C. N.

1996-01-01

This report presents the results of a comprehensive research and development project that was conducted over a three-year period to develop new technologies for testing the attachment of sensors to solid materials for the following NASA applications: (1) testing the performance of composites that are used for the lining of solid rocket motor nozzles, (2) testing the bonding of surface-mounted platinum resistance thermometers that are used on fuel and oxidizer lines of the space shuttle to detect valve leaks by monitoring temperature, (3) testing the attachment of strain gages that are used in testing the performance of space shuttle main engines, and (4) testing the thermocouples that are used for determining the performance of blast tube liner material in solid rocket boosters.

Operation Hardtack. Project 2.8. Fallout Measurements by Aircraft and Rocket Sampling,

DTIC Science & Technology

1985-09-01

EXTRICTED WVE O OPERATION HARDTACK-PROJECT 2.8 Fallout Measurements by Aircraft and Rocket Sampling S. L. Whitcher L R. Bunney R. R. Soule U.S. Naval...Aircraft and Rocket Sampling , Extracted Version 12. PERSONAL AUTHOR(S) Whitcher, S.L.; Bunney, L.R.; Soule , R.R.; and daRoza, R.A. 13a. TYPE OF REPORT 13b...ROCKET SAMPLING S. L. Whitcher L.R. Bunney Rt. R. Soule , Project Officer U.S. Nav2l Radiological Defense Laboratory San Francisco 24, California R.A

A more thorough analysis of water rockets: Moist adiabats, transient flows, and inertial forces in a soda bottle

NASA Astrophysics Data System (ADS)

Gommes, Cedric J.

2010-03-01

Although water rockets are widely used to illustrate first year physics principles, accurate measurements show that they outperform the usual textbook analysis at the beginning of the thrust phase. This paper gives a more thorough analysis of this problem. It is shown that the air expansion in the rocket is accompanied by water vapor condensation, which provides an extra thrust; the downward acceleration of water within the rocket also contributes to the thrust, an effect that is negligible in other types of rockets; the apparent gravity resulting from the acceleration of the rocket contributes as much to water ejection as does the pressure difference between the inside and outside of the rocket; and the water flow is transient, which precludes the use of Bernoulli's equation. Although none of these effects is negligible, they mostly cancel each other, and the overall accuracy of the analysis is only marginally improved. There remains a difference between theory and experiment with water rockets.

77 FR 4917 - Taking and Importing Marine Mammals: U.S. Navy Training in 12 Range Complexes and U.S. Air Force...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-01

... missile and rocket launches that the USAF conducts. DATES: Effective on February 1, 2012. ADDRESSES... rockets that could be launched over the course of the 5-year rule and indicated that marine mammal take... flexibility in the types and amounts of missile and rocket launches that they conduct. NMFS now amends the...

CLASP: A UV Spectropolarimeter on a Sounding Rocket for Probing theChromosphere-Corona Transition Regio

NASA Astrophysics Data System (ADS)

Ishikawa, Ryohko; Kano, Ryouhei; Winebarger, Amy; Auchere, Frederic; Trujillo Bueno, Javier; Bando, Takamasa; Narukage, Noriyuki; Kobayashi, Ken; Katsukawa, Yukio; Kubo, Masahito; Ishikawa, Shin-nosuke; Giono, Gabriel; Tsuneta, Saku; Hara, Hirohisa; Suematsu, Yoshinori; Shimizu, Toshifumi; Sakao, Taro; Ichimoto, Kiyoshi; Cirtain, Jonathan; De Pontieu, Bart; Casini, Roberto; Manso Sainz, Rafael; Asensio Ramos, Andres; Stepan, Jiri; Belluzzi, Luca

2015-08-01

The wish to understand the energetic phenomena of the outer solar atmosphere makes it increasingly important to achieve quantitative information on the magnetic field in the chromosphere-corona transition region. To this end, we need to measure and model the linear polarization produced by scattering processes and the Hanle effect in strong UV resonance lines, such as the hydrogen Lyman-alpha line. A team consisting of Japan, USA, Spain, France, and Norway has been developing a sounding rocket experiment called the Chromospheric Lyman-alpha Spectro-Polarimeter (CLASP). The aim is to detect the scattering polarization produced by anisotropic radiation pumping in the hydrogen Lyman-alpha line (121.6 nm), and via the Hanle effect to try to constrain the magnetic field vector in the upper chromosphere and transition region. In this talk, we will present an overview of our CLASP mission, its scientific objectives, ground tests made, and the latest information on the launch planned for the Summer of 2015.

Kinematic Description of Elite Vs. Low Level Players in Team-Handball Jump Throw

PubMed Central

Wagner, Herbert; Buchecker, Michael; von Duvillard, Serge P.; Müller, Erich

2010-01-01

The jump throw is the most applied throwing technique in team- handball (Wagner et al., 2008); however, a comprehensive analysis of 3D-kinematics of the team-handball jump throw is lacking. Therefore, the purpose of our study was: 1) to measure differences in ball release speed in team- handball jump throw and anthropometric parameters between groups of different levels of performance and (2) to analyze upper body 3D-kinematics (flexion/extension and rotation) to determine significant differences between these groups. Three-dimensional kinematic data was analyzed via the Vicon MX 13 motion capturing system (Vicon Peak, Oxford, UK) from 26 male team-handball players of different performance levels (mean age: 21.2 ± 5.0 years). The participants were instructed to throw the ball (IHF Size 3) onto a target at 8 m distance, and to hit the center of a square of 1 × 1 m at about eye level (1.75 m), with maximum ball release speed. Significant differences between elite vs. low level players were found in the ball release speed (p < 0.001), body height (p < 0.05), body weight (p < 0.05), maximal trunk internal rotation (p < 0.05), trunk flexion (p < 0.01) and forearm pronation (p < 0.05) as well as trunk flexion (p < 0.05) and shoulder internal rotation (p < 0.001) angular velocity at ball release. Results of our study suggest that team-handball players who were taller and of greater body weight have the ability to achieve a higher ball release speed in the jump throw, and that an increase in trunk flexion and rotation angular velocity improve the performance in team-handball jump throw that should result in an increase of ball release speed. Key points Team-handball players who were taller and of greater body weight have the ability to achieve a higher ball release speed. An increase in trunk flexion, trunk rotation and shoulder internal rotation angular velocity should result in an increase of ball release speed. Trunk movements are normally well observable for experienced coaches, easy correctable and therefore practical to improve the performance in team-handball jump throw of low level players during training without using complex measurement devices. PMID:24149381

Kinematic description of elite vs. Low level players in team-handball jump throw.

PubMed

Wagner, Herbert; Buchecker, Michael; von Duvillard, Serge P; Müller, Erich

2010-01-01

The jump throw is the most applied throwing technique in team- handball (Wagner et al., 2008); however, a comprehensive analysis of 3D-kinematics of the team-handball jump throw is lacking. Therefore, the purpose of our study was: 1) to measure differences in ball release speed in team- handball jump throw and anthropometric parameters between groups of different levels of performance and (2) to analyze upper body 3D-kinematics (flexion/extension and rotation) to determine significant differences between these groups. Three-dimensional kinematic data was analyzed via the Vicon MX 13 motion capturing system (Vicon Peak, Oxford, UK) from 26 male team-handball players of different performance levels (mean age: 21.2 ± 5.0 years). The participants were instructed to throw the ball (IHF Size 3) onto a target at 8 m distance, and to hit the center of a square of 1 × 1 m at about eye level (1.75 m), with maximum ball release speed. Significant differences between elite vs. low level players were found in the ball release speed (p < 0.001), body height (p < 0.05), body weight (p < 0.05), maximal trunk internal rotation (p < 0.05), trunk flexion (p < 0.01) and forearm pronation (p < 0.05) as well as trunk flexion (p < 0.05) and shoulder internal rotation (p < 0.001) angular velocity at ball release. Results of our study suggest that team-handball players who were taller and of greater body weight have the ability to achieve a higher ball release speed in the jump throw, and that an increase in trunk flexion and rotation angular velocity improve the performance in team-handball jump throw that should result in an increase of ball release speed. Key pointsTeam-handball players who were taller and of greater body weight have the ability to achieve a higher ball release speed.An increase in trunk flexion, trunk rotation and shoulder internal rotation angular velocity should result in an increase of ball release speed.Trunk movements are normally well observable for experienced coaches, easy correctable and therefore practical to improve the performance in team-handball jump throw of low level players during training without using complex measurement devices.

How to Plan a Theme Based Field Day

ERIC Educational Resources Information Center

Shea, Scott A.; Fagala, Lisa M.

2006-01-01

Having a theme-based field day is a great way to get away from doing the traditional track-and-field type events, such as the softball throw, 50 yard dash, and sack race, year after year. In a theme-based field day format all stations or events are planned around a particular theme. This allows the teacher to be creative while also adding…

Some Foreign Educational Surveys. Bulletin, 1915, No. 37. Whole Number 664

ERIC Educational Resources Information Center

Mahoney, James

1915-01-01

The educational surveys of which some account is given in this bulletin do not by any means represent all the foreign investigations that have been made; it is believed, however, that they will serve to acquaint American students of education with certain foreign types, and at the same time throw some light on the history of surveys and of…

He Throws like a Girl (but Only when He's Sad): Emotion Affects Sex-Decoding of Biological Motion Displays

ERIC Educational Resources Information Center

Johnson, Kerri L.; McKay, Lawrie S.; Pollick, Frank E.

2011-01-01

Gender stereotypes have been implicated in sex-typed perceptions of facial emotion. Such interpretations were recently called into question because facial cues of emotion are confounded with sexually dimorphic facial cues. Here we examine the role of visual cues and gender stereotypes in perceptions of biological motion displays, thus overcoming…

Rocket-Plume Spectroscopy Simulation for Hydrocarbon-Fueled Rocket Engines

NASA Technical Reports Server (NTRS)

Tejwani, Gopal D.

2010-01-01

The UV-Vis spectroscopic system for plume diagnostics monitors rocket engine health by using several analytical tools developed at Stennis Space Center (SSC), including the rocket plume spectroscopy simulation code (RPSSC), to identify and quantify the alloys from the metallic elements observed in engine plumes. Because the hydrocarbon-fueled rocket engine is likely to contain C2, CO, CH, CN, and NO in addition to OH and H2O, the relevant electronic bands of these molecules in the spectral range of 300 to 850 nm in the RPSSC have been included. SSC incorporated several enhancements and modifications to the original line-by-line spectral simulation computer program implemented for plume spectral data analysis and quantification in 1994. These changes made the program applicable to the Space Shuttle Main Engine (SSME) and the Diagnostic Testbed Facility Thruster (DTFT) exhaust plume spectral data. Modifications included updating the molecular and spectral parameters for OH, adding spectral parameter input files optimized for the 10 elements of interest in the spectral range from 320 to 430 nm and linking the output to graphing and analysis packages. Additionally, the ability to handle the non-uniform wavelength interval at which the spectral computations are made was added. This allowed a precise superposition of wavelengths at which the spectral measurements have been made with the wavelengths at which the spectral computations are done by using the line-by-line (LBL) code. To account for hydrocarbon combustion products in the plume, which might interfere with detection and quantification of metallic elements in the spectral region of 300 to 850 nm, the spectroscopic code has been enhanced to include the carbon-based combustion species of C2, CO, and CH. In addition, CN and NO have spectral bands in 300 to 850 nm and, while these molecules are not direct products of hydrocarbon-oxygen combustion systems, they can show up if nitrogen or a nitrogen compound is present as an impurity in the propellants and/or these can form in the boundary layer as a result of interaction of the hot plume with the atmosphere during the ground testing of engines. Ten additional electronic band systems of these five molecules have been included into the code. A comprehensive literature search was conducted to obtain the most accurate values for the molecular and the spectral parameters, including Franck-Cordon factors and electronic transition moments for all ten band systems. For each elemental transition in the RPSSC, six spectral parameters - Doppler broadened line width at half-height, pressure-broadened line width at half-height, electronic multiplicity of the upper state, electronic term energy of the upper state, Einstein transition probability coefficient, and the atomic line center - are required. Input files have been created for ten elements of Ni, Fe, Cr, Co, Cu, Ca, Mn, Al, Ag, and Pd, which retain only relatively moderate to strong transitions in 300 to 430 nm spectral range for each element. The number of transitions in the input files is 68 for Ni; 148 for Fe; 6 for Cr; 87 for Co; 1 for Ca; 3 for Mn; 2 each for Cu, Al, and Ag; and 11 for Pd.

Significant Climate Changes Caused by Soot Emitted From Rockets in the Stratosphere

NASA Astrophysics Data System (ADS)

Mills, M. J.; Ross, M.; Toohey, D. W.

2010-12-01

A new type of hydrocarbon rocket engine with a larger soot emission index than current kerosene rockets is expected to power a fleet of suborbital rockets for commercial and scientific purposes in coming decades. At projected launch rates, emissions from these rockets will create a persistent soot layer in the northern middle stratosphere that would disproportionally affect the Earth’s atmosphere and cryosphere. A global climate model predicts that thermal forcing in the rocket soot layer will cause significant changes in the global atmospheric circulation and distributions of ozone and temperature. Tropical ozone columns decline as much as 1%, while polar ozone columns increase by up to 6%. Polar surface temperatures rise one Kelvin regionally and polar summer sea ice fractions shrink between 5 - 15%. After 20 years of suborbital rocket fleet operation, globally averaged radiative forcing (RF) from rocket soot exceeds the RF from rocket CO_{2} by six orders of magnitude, but remains small, comparable to the global RF from aviation. The response of the climate system is surprising given the small forcing, and should be investigated further with different climate models.

Changes in Muscle Architecture, Explosive Ability, and Track and Field Throwing Performance Throughout a Competitive Season and After a Taper.

PubMed

Bazyler, Caleb D; Mizuguchi, Satoshi; Harrison, Alex P; Sato, Kimitake; Kavanaugh, Ashley A; DeWeese, Brad H; Stone, Michael H

2017-10-01

The purpose of this study was to examine the effects of an overreach and taper on measures of muscle architecture, jumping, and throwing performance in Division I collegiate throwers preparing for conference championships. Six collegiate track and field throwers (3 hammer, 2 discus, 1 javelin) trained for 12 weeks using a block-periodization model culminating with a 1-week overreach followed by a 3-week taper (ORT). Session rating of perceived exertion training load (RPETL) and strength training volume-load times bar displacement (VLd) were recorded weekly. Athletes were tested pre-ORT and post-ORT on measures of vastus lateralis architecture, unloaded and loaded squat and countermovement jump performance, underhand and overhead throwing performance, and competition throwing performance. There was a statistical reduction in weight training VLd/session (d = 1.21, p ≤ 0.05) and RPETL/session (d = 0.9, p ≤ 0.05) between the in-season and ORT training phases. Five of 6 athletes improved overhead throw and competition throwing performance after the ORT (d = 0.50, p ≤ 0.05). Vastus lateralis muscle thickness statistically increased after the in-season training phase (d = 0.28, p ≤ 0.05) but did not change after the ORT. Unloaded countermovement jump peak force and relative peak power improved significantly after the ORT (d = 0.59, p ≤ 0.05, d = 0.31, p ≤ 0.05, respectively). These findings demonstrate that an overreaching week followed by a 3-week taper is an effective means of improving explosive ability and throwing performance in collegiate track and field throwers despite the absence of detectable changes in muscle architecture.

Clavicle length, throwing performance and the reconstruction of the Homo erectus shoulder.

PubMed

Roach, Neil T; Richmond, Brian G

2015-03-01

Powerful, accurate throwing may have been an important mode of early hunting and defense. Previous work has shown that throwing performance is functionally linked to several anatomical shifts in the upper body that occurred during human evolution. The final shift to occur is the inferior reorientation of the shoulder. Fossil scapulae show the earliest evidence of a more inferior glenoid in Homo erectus. However, where the scapula rests on the thorax is uncertain. The relative length of the clavicle, the only skeletal attachment of the scapula to the torso, is quite variable. Depending on which fossils or skeletal measures are used to reconstruct the H. erectus shoulder, either a novel, anteriorly facing shoulder configuration or a modern human-like lateral orientation is possible. These competing hypotheses have led to very different conclusions regarding the throwing ability and hunting behavior of early Homo. Here, we evaluate competing models of H. erectus shoulder morphology and examine how these models relate to throwing performance. To address these questions, we collected skeletal measures from fossil and extant taxa, as well as anthropometric (N = 36) and kinematic (N = 27) data from Daasanach throwers from northwestern Kenya. Our data show that all H. erectus fossil clavicles fall within the normal range of modern human variation. We find that a commonly used metric for normalizing clavicle length, the claviculohumeral ratio, poorly predicts shoulder position on the torso. Furthermore, no significant relationship between clavicle length and any measure of throwing performance was found. These data support reconstructing the H. erectus shoulder as modern human-like, with a laterally facing glenoid, and suggest that the capacity for high speed throwing dates back nearly two million years. Copyright © 2014 Elsevier Ltd. All rights reserved.

Definition of Throw-Away Detectors (TADs) and VLF antenna for the AMPS laboratory

NASA Technical Reports Server (NTRS)

Koons, H. C.; Fennell, J. F.

1975-01-01

A Throw Away Detector (TAD)/subsatellite to be used as an experiment platform for the test flights to map the EMI from the shuttle and during the AMPS science flights is defined. A range of instrument platforms of varying capabilities is examined with emphasis on the EMI test vehicle. The operational support requirements of TAD/subsatellites are determined. The throw away detector is envisioned as a simple instrument package for supporting specific experiments.

Associations Between Rate of Force Development Metrics and Throwing Velocity in Elite Team Handball Players: a Short Research Report

PubMed Central

Marques, Mário C.; Saavedra, Francisco J.; Abrantes, Catarina; Aidar, Felipe J.

2011-01-01

Performance assessment has become an invaluable component of monitoring participant’s development in distinct sports, yet limited and contradictory data are available in trained subjects. The purpose of this study was to examine the relationship between ball throwing velocity during a 3-step running throw in elite team handball players and selected measures of rate of force development like force, power, velocity, and bar displacement during a concentric only bench press exercise in elite male handball players. Fitteen elite senior male team handball players volunteered to participate. Each volunteer had power and bar velocity measured during a concentric only bench press test with 25, 35, and 45 kg as well as having one-repetition maximum strength determined. Ball throwing velocity was evaluated with a standard 3-step running throw using a radar gun. The results of this study indicated significant associations between ball velocity and time at maximum rate of force development (0, 66; p<0.05) and rate of force development at peak force (0,56; p<0.05) only with 25kg load. The current research indicated that ball velocity was only median associated with maximum rate of force development with light loads. A training regimen designed to improve ball-throwing velocity in elite male team handball players should emphasize bench press movement using light loads. PMID:23487363

The biomechanics of an overarm throwing task: a simulation model examination of optimal timing of muscle activations.

PubMed

Chowdhary, A G; Challis, J H

2001-07-07

A series of overarm throws, constrained to the parasagittal plane, were simulated using a muscle model actuated two-segment model representing the forearm and hand plus projectile. The parameters defining the modeled muscles and the anthropometry of the two-segment models were specific to the two young male subjects. All simulations commenced from a position of full elbow flexion and full wrist extension. The study was designed to elucidate the optimal inter-muscular coordination strategies for throwing projectiles to achieve maximum range, as well as maximum projectile kinetic energy for a variety of projectile masses. A proximal to distal (PD) sequence of muscle activations was seen in many of the simulated throws but not all. Under certain conditions moment reversal produced a longer throw and greater projectile energy, and deactivation of the muscles resulted in increased projectile energy. Therefore, simple timing of muscle activation does not fully describe the patterns of muscle recruitment which can produce optimal throws. The models of the two subjects required different timings of muscle activations, and for some of the tasks used different coordination patterns. Optimal strategies were found to vary with the mass of the projectile, the anthropometry and the muscle characteristics of the subjects modeled. The tasks examined were relatively simple, but basic rules for coordinating these tasks were not evident. Copyright 2001 Academic Press.

Assessment and monitoring of ballistic and maximal upper-body strength qualities in athletes.

PubMed

Young, Kieran P; Haff, G Gregory; Newton, Robert U; Gabbett, Tim J; Sheppard, Jeremy M

2015-03-01

To evaluate whether the dynamic strength index (DSI: ballistic peak force/isometric peak force) could be effectively used to guide specific training interventions and detect training-induced changes in maximal and ballistic strength. Twenty-four elite male athletes were assessed in the isometric bench press and a 45% 1-repetition-maximum (1RM) ballistic bench throw using a force plate and linear position transducer. The DSI was calculated using the peak force values obtained during the ballistic bench throw and isometric bench press. Athletes were then allocated into 2 groups as matched pairs based on their DSI and strength in the 1RM bench press. Over the 5 wk of training, athletes performed either high-load (80-100% 1RM) bench press or moderate-load (40-55% 1RM) ballistic bench throws. The DSI was sensitive to disparate training methods, with the bench-press group increasing isometric bench-press peak force (P=.035, 91% likely), and the ballistic-bench-throw group increasing bench-throw peak force to a greater extent (P≤.001, 83% likely). A significant increase (P≤.001, 93% likely) in the DSI was observed for both groups. The DSI can be used to guide specific training interventions and can detect training-induced changes in isometric bench-press and ballistic bench-throw peak force over periods as short as 5 wk.

Seat surface inclination may affect postural stability during Boccia ball throwing in children with cerebral palsy.

PubMed

Tsai, Yung-Shen; Yu, Yi-Chen; Huang, Po-Chang; Cheng, Hsin-Yi Kathy

2014-12-01

The aim of the study was to examine how seat surface inclination affects Boccia ball throwing movement and postural stability among children with cerebral palsy (CP). Twelve children with bilateral spastic CP (3 with gross motor function classification system Level I, 5 with Level II, and 4 with Level III) participated in this study. All participants underwent pediatric reach tests and ball throwing performance analyses while seated on 15° anterior- or posterior-inclined, and horizontal surfaces. An electromagnetic motion analysis system was synchronized with a force plate to assess throwing motion and postural stability. The results of the pediatric reach test (p = 0.026), the amplitude of elbow movement (p = 0.036), peak vertical ground reaction force (PVGRF) (p < 0.001), and movement range of the center of pressure (COP) (p < 0.020) were significantly affected by seat inclination during throwing. Post hoc comparisons showed that anterior inclination allowed greater amplitude of elbow movement and PVGRF, and less COP movement range compared with the other inclines. Posterior inclination yielded less reaching distance and PVGRF, and greater COP movement range compared with the other inclines. The anterior-inclined seat yielded superior postural stability for throwing Boccia balls among children with bilateral spastic CP, whereas the posterior-inclined seat caused difficulty. Copyright © 2014 Elsevier Ltd. All rights reserved.

Associations between rate of force development metrics and throwing velocity in elite team handball players: a short research report.

PubMed

Marques, Mário C; Saavedra, Francisco J; Abrantes, Catarina; Aidar, Felipe J

2011-09-01

Performance assessment has become an invaluable component of monitoring participant's development in distinct sports, yet limited and contradictory data are available in trained subjects. The purpose of this study was to examine the relationship between ball throwing velocity during a 3-step running throw in elite team handball players and selected measures of rate of force development like force, power, velocity, and bar displacement during a concentric only bench press exercise in elite male handball players. Fitteen elite senior male team handball players volunteered to participate. Each volunteer had power and bar velocity measured during a concentric only bench press test with 25, 35, and 45 kg as well as having one-repetition maximum strength determined. Ball throwing velocity was evaluated with a standard 3-step running throw using a radar gun. The results of this study indicated significant associations between ball velocity and time at maximum rate of force development (0, 66; p<0.05) and rate of force development at peak force (0,56; p<0.05) only with 25kg load. The current research indicated that ball velocity was only median associated with maximum rate of force development with light loads. A training regimen designed to improve ball-throwing velocity in elite male team handball players should emphasize bench press movement using light loads.

Proprioception and Throwing Accuracy in the Dominant Shoulder After Cryotherapy

PubMed Central

Wassinger, Craig A; Myers, Joseph B; Gatti, Joseph M; Conley, Kevin M; Lephart, Scott M

2007-01-01

Context: Application of cryotherapy modalities is common after acute shoulder injury and as part of rehabilitation. During athletic events, athletes may return to play after this treatment. The effects of cryotherapy on dominant shoulder proprioception have been assessed, yet the effects on throwing performance are unknown. Objective: To determine the effects of a cryotherapy application on shoulder proprioception and throwing accuracy. Design: Single-group, pretest-posttest control session design. Setting: University-based biomechanics laboratory. Patients or Other Participants: Healthy college-aged subjects (n = 22). Intervention(s): Twenty-minute ice pack application to the dominant shoulder. Main Outcome Measure(s): Active joint position replication, path of joint motion replication, and the Functional Throwing Performance Index. Results: Subjects demonstrated significant increases in deviation for path of joint motion replication when moving from 90° of abduction with 90° of external rotation to 20° of flexion with neutral shoulder rotation after ice pack application. Also, subjects exhibited a decrease in Functional Throwing Performance Index after cryotherapy application. No differences were found in subjects for active joint position replication after cryotherapy application. Conclusions: Proprioception and throwing accuracy were decreased after ice pack application to the shoulder. It is important that clinicians understand the deficits that occur after cryotherapy, as this modality is commonly used following acute injury and during rehabilitation. This information should also be considered when attempting to return an athlete to play after treatment. PMID:17597948

Stretching

MedlinePlus

... your particular sport. For instance, if you play baseball, you might focus on your shoulder for throwing. ... your particular sport. For instance, if you play baseball you might focus on your shoulder for throwing ...

Scaphoid tuberosity excursion is minimized during a dart-throwing motion: A biomechanical study.

PubMed

Werner, Frederick W; Sutton, Levi G; Basu, Niladri; Short, Walter H; Moritomo, Hisao; St-Amand, Hugo

2016-01-01

The purpose of this study was to determine whether the excursion of the scaphoid tuberosity and therefore scaphoid motion is minimized during a dart-throwing motion. Scaphoid tuberosity excursion was studied as an indicator of scaphoid motion in 29 cadaver wrists as they were moved through wrist flexion-extension, radioulnar deviation, and a dart-throwing motion. Study results demonstrate that excursion was significantly less during the dart-throwing motion than during either wrist flexion-extension or radioulnar deviation. If the goal of early wrist motion after carpal ligament or distal radius injury and reconstruction is to minimize loading of the healing structures, a wrist motion in which scaphoid motion is minimal should reduce length changes in associated ligamentous structures. Therefore, during rehabilitation, if a patient uses a dart-throwing motion that minimizes his or her scaphoid tuberosity excursion, there should be minimal changes in ligament loading while still allowing wrist motion. Bench research, biomechanics, and cross-sectional. Not applicable. The study was laboratory based. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Biomechanical factors critical for performance in the men's javelin throw.

PubMed

Morriss, C; Bartlett, R

1996-06-01

In the men's javelin event the athlete throws an 800g implement into a 40 degrees sector. The objective is to throw as far as possible. Compared with most other throwing implements, the javelin is relatively aerodynamic. Even so, the most important release parameter is still the release speed. Maximising this parameter gives the athlete the best chance of attaining success in the event. For an elite thrower, as much as 70% of the release speed of the javelin is developed in the last 0.1 second. As such, the movements of throwers during this period and immediately preceding it have received attention from researchers. It would appear that a thrower's body position at the instant of final foot strike, his ability to transfer momentum between the lower body and the upper body during the delivery, and coordination of the working body segments in the most effective manner are linked to his success in the event. This paper reviews the most important biomechanical research on the men's javelin throw and highlights findings such as these which may improve the understanding of how elite javelin throwers achieve success.

Effects of Dehydration on Cricket Specific Skill Performance in Hot and Humid Conditions.

PubMed

Gamage, Janaka P; De Silva, Angela P; Nalliah, Arjan K; Galloway, Stuart D R

2016-12-01

The aim of the current study was to assess the effects of dehydration on cricket specific motor skill performance among fast-bowlers, fielders, and batsmen playing in a hot and humid environment. 10 fast-bowlers, 12 fielders and 8 batsmen participated in two field trials conducted 7 days apart: a fluid provision trial (FP) and a fluid restriction trial (FR). Each trial consisted of a 2-hr standardized training session and pretraining and posttraining skill performance assessments. Bowling speed and accuracy (line and length), throwing speed and accuracy (overarm, sidearm and underarm) and timed running between wickets (1, 2, and 3 runs) was assessed pre to posttraining in each trial. Mass loss was 0.6 ± 0.3 kg (0.9 ± 0.5%) in FP, and 2.6 ± 0.5kg (3.7 ± 0.8%) in FR trials. Maintaining mass within 1% of initial values did not cause any significant skill performance decline. However, the dehydration on the FR trial induced a significant time and trial effect for bowling speed by 1.0 ± 0.8% reduction (0.3 ± 0.8% reduction in FP trial; p < .01) and 19.8 ± 17.3% reduction in bowling accuracy for line (3.6 ± 14.2% reduction in FP trial; p < .01), but no effect on bowling length. A significant decline was noted in the FR trial for throwing speed for overarm (6.6 ± 4.1%; p < .01; 1.6 ± 3.4% reduction in FP trial) and sidearm (4.1 ± 2.3%; p < .01; 0.6 ± 4.7% increase in FP trial) techniques, and for throwing accuracy for overarm (14.2 ± 16.3%; p < .01; 0.8 ± 24.2% increase in FP trial) and sidearm (22.3 ± 13.3%; p < .05; 3.2 ± 34.9% reduction in FP trial) techniques. Batsmen demonstrated significant performance drop in making three runs (0.8 ± 1.2% increase in time in FP trial and 2.2 ± 1.7% increase in time in FR trial; p < .01). Moderate-severe dehydration of 3.7% body mass loss significantly impairs motor skill performance among cricketers, particularly bowlers and fielders, playing in hot and humid conditions. Fluid ingestion strategies maintaining mass loss within 1% prevented a decline in skill performance.

NASA's Ground-Based Observing Campaigns of Rocket Bodies with the UKIRT and NASA ES-MCAT Telescopes

NASA Technical Reports Server (NTRS)

Lederer, Susan M.; Buckalew, Brent A.; Anz-Meador, Phillip; Cowardin, Heather M.; Frith, James M.; Matney, Mark

2017-01-01

Rocket bodies comprise a class of human-made space debris that are at the same time essential for launching every spacecraft from the Earth, but are also a significant source of debris both as intact objects, as well as fragmented debris. Unspent fuel has been long theorized as a potential cause of catastrophic rocket body break-ups. Given typical orbital speeds range from approximately 2-3 kilometers per second at Geosynchronous Orbit (GEO) and up to 15 kilometers per second in low Earth orbit (LEO), collisions with uncatalogued and undetected debris can also cause catastrophic breakups. Understanding break-ups is a necessary step in preventing them, and one key step in that process is to correlate and characterize daughter fragments with their parent bodies. Two very different methods include (1) conducting photometric surveys to correlate an object's motion and orbital elements to the parent body, and (2) characterizing what materials comprise the target to determine whether those materials are consistent with the parent body or like objects. With this in mind, photometric data were taken shortly after the breakup of one rocket body for short-term orbital studies, and a suite of spectral data were taken of rocket bodies that are fully intact to compare with debris, for characterization studies. Targets included Titan Transtage, Briz-M, and Ariane rocket bodies and debris. Spectra of each sub-class of rocket body were very similar within their rocket body type, but differed distinctly from one type to the next, supporting the effectiveness of this approach.

Perceptual training effects on anticipation of direct and deceptive 7-m throws in handball.

PubMed

Alsharji, Khaled E; Wade, Michael G

2016-01-01

We examined the effectiveness of perceptual training on the performance of handball goalkeepers when anticipating the direction of both direct and deceptive 7-m throws. Skilled goalkeepers were assigned equally to three matched-ability groups based on their pre-test performance: a perceptual training group (n = 14) received video-based perceptual training, a placebo training group (n = 14) received video-based regular training and a control group received no training. Participants in the perceptual training group significantly improved their performance compared to both placebo and control groups; however, anticipation of deceptive throws improved less than for direct throws. The results confirm that although anticipating deception in handball is a challenging task for goalkeepers, task-specific perceptual training can minimise its effect and improve performance.

Convection and electrodynamic signatures in the vicinity of a Sun-aligned arc: Results from the Polar Acceleration Regions and Convection Study (Polar ARCS)

NASA Technical Reports Server (NTRS)

Weiss, L. A.; Weber, E. J.; Reiff, P. H.; Sharber, J. R.; Winningham, J. D.; Primdahl, F.; Mikkelsen, I. S.; Seifring, C.; Wescott, Eugene M.

1994-01-01

An experimental campaign designed to study high-latitude auroral arcs was conducted in Sondre Stromfjord, Greenland, on February 26, 1987. The Polar Acceleration Regions and Convection Study (Polar ARCS) consisted of a coordinated set of ground-based, airborne, and sounding rocket measurements of a weak, sun-aligned arc system within the duskside polar cap. A rocket-borne barium release experiment, two DMSP satellite overflights, all-sky photography, and incoherent scatter radar measurements provided information on the large-scale plasma convection over the polar cap region while a second rocket instrumented with a DC magnetometer, Langmuir and electric field probes, and an electron spectrometer provided measurements of small-scale electrodynamics. The large-scale data indicate that small, sun-aligned precipitation events formed within a region of antisunward convection between the duskside auroral oval and a large sun-aligned arc further poleward. This convection signature, used to assess the relationship of the sun-aligned arc to the large-scale magnetospheric configuration, is found to be consistent with either a model in which the arc formed on open field lines on the dusk side of a bifurcated polar cap or on closed field lines threading an expanded low-latitude boundary layer, but not a model in which the polar cap arc field lines map to an expanded plasma sheet. The antisunward convection signature may also be explained by a model in which the polar cap arc formed on long field lines recently reconnected through a highly skewed plasma sheet. The small-scale measurements indicate the rocket passed through three narrow (less than 20 km) regions of low-energy (less than 100 eV) electron precipitation in which the electric and magnetic field perturbations were well correlated. These precipitation events are shown to be associated with regions of downward Poynting flux and small-scale upward and downward field-aligned currents of 1-2 micro-A/sq m. The paired field-aligned currents are associated with velocity shears (higher and lower speed streams) embedded in the region of antisunward flow.

Monitoring Workload in Throwing-Dominant Sports: A Systematic Review.

PubMed

Black, Georgia M; Gabbett, Tim J; Cole, Michael H; Naughton, Geraldine

2016-10-01

The ability to monitor training load accurately in professional sports is proving vital for athlete preparedness and injury prevention. While numerous monitoring techniques have been developed to assess the running demands of many team sports, these methods are not well suited to throwing-dominant sports that are infrequently linked to high running volumes. Therefore, other techniques are required to monitor the differing demands of these sports to ensure athletes are adequately prepared for competition. To investigate the different methodologies used to quantitatively monitor training load in throwing-dominant sports. A systematic review of the methods used to monitor training load in throwing-dominant sports was conducted using variations of terms that described different load-monitoring techniques and different sports. Studies included in this review were published prior to June 2015 and were identified through a systematic search of four electronic databases including Academic Search Complete, CINAHL, Medline and SPORTDiscus. Only full-length peer-reviewed articles investigating workload monitoring in throwing-dominant sports were selected for review. A total of 8098 studies were initially retrieved from the four databases and 7334 results were removed as they were either duplicates, review articles, non-peer-reviewed articles, conference abstracts or articles written in languages other than English. After screening the titles and abstracts of the remaining papers, 28 full-text papers were reviewed, resulting in the identification of 20 articles meeting the inclusion criteria for monitoring workloads in throwing-dominant sports. Reference lists of selected articles were then scanned to identify other potential articles, which yielded one additional article. Ten articles investigated workload monitoring in cricket, while baseball provided eight results, and handball, softball and water polo each contributed one article. Results demonstrated varying techniques used to monitor workload and purposes for monitoring workload, encompassing the relationship between workload and injury, individual responses to workloads, the effect of workload on subsequent performance and the future directions of workload-monitoring techniques. This systematic review highlighted a number of simple and effective workload-monitoring techniques implemented across a variety of throwing-dominant sports. The current literature placed an emphasis on the relationship between workload and injury. However, due to differences in chronological and training age, inconsistent injury definitions and time frames used for monitoring, injury thresholds remain unclear in throwing-dominant sports. Furthermore, although research has examined total workload, the intensity of workload is often neglected. Additional research on the reliability of self-reported workload data is also required to validate existing relationships between workload and injury. Considering the existing disparity within the literature, it is likely that throwing-dominant sports would benefit from the development of an automated monitoring tool to objectively assess throwing-related workloads in conjunction with well-established internal measures of load in athletes.

Multiple Wheel Throwing: And Chess Sets.

ERIC Educational Resources Information Center

Sapiro, Maurice

1978-01-01

A chess set project is suggested to teach multiple throwing, the creation on a potter's wheel of several pieces of similar configuration. Processes and finished sets are illustrated with photographs. (SJL)

Effects of in-season circuit training on physical abilities in male handball players.

PubMed

Hermassi, Souhail; Wollny, Rainer; Schwesig, René; Shephard, Roy J; Chelly, Mohamed Souhaiel

2017-10-07

This study analyzed the effects of a resistance-type circuit training program (RCT) (30-35 minutes, performed twice a week for 10 weeks) on male handball players. Twenty-two males were divided into experimental (E; age 20.3 ± 0.5 years) and control groups (C; age 20.1± 0.5 years). Measures before and after RCT included squat (SJ) and countermovement jumps (CMJ), one repetition maximum (1-RM) ofbench press, pull-over and back half-squats, throwing velocity (a 3-step throw with run (RT), and a jump throw (JT)), repeated-sprint ability (six 2 x 15-m shuttle sprints with recording of best time for a single trial), anthropometric estimates of leg and thigh muscle volumes and mean thigh cross-sectional area (CSA), and a test of agility. The agility T-half test showed a significant interaction effect (p=0.001; η=0.422), with an inter-group difference in effect size (d) of 1.27 (dTG=1.24 vs. dCG=-0.03). The SJ displayed no interaction effect. The interaction effects for half back-squat (d=2.73, η=0.740) and CMJ (d=3.76, η=0.700) were large, but that for RT was smaller (η=0.460) than that for JT (η=0.745). The throwing velocity of C decreased for both measures, with negative effect sizes (d=-0.18 and d=-0.93 respectively). Upper body, leg, and thigh muscle volumes and thigh CSA increased significantly after resistance training. However, repeated-sprint parameters showed no significant changes. During the competitive season, 10 weeks of RCT with only 2 training sessions per week improved numerous measures of athletic performance in handball players, and such conditioning can be highly recommended as part of the annual training program for elite handball players.

Prediction of Launch Vehicle Ignition Overpressure and Liftoff Acoustics

NASA Technical Reports Server (NTRS)

Casiano, Matthew

2009-01-01

The LAIOP (Launch Vehicle Ignition Overpressure and Liftoff Acoustic Environments) program predicts the external pressure environment generated during liftoff for a large variety of rocket types. These environments include ignition overpressure, produced by the rapid acceleration of exhaust gases during rocket-engine start transient, and launch acoustics, produced by turbulence in the rocket plume. The ignition overpressure predictions are time-based, and the launch acoustic predictions are frequency-based. Additionally, the software can predict ignition overpressure mitigation, using water-spray injection into the rocket exhaust stream, for a limited number of configurations. The framework developed for these predictions is extensive, though some options require additional relevant data and development time. Once these options are enabled, the already extensively capable code will be further enhanced. The rockets, or launch vehicles, can either be elliptically or cylindrically shaped, and up to eight strap-on structures (boosters or tanks) are allowed. Up to four engines are allowed for the core launch vehicle, which can be of two different types. Also, two different sizes of strap-on structures can be used, and two different types of booster engines are allowed. Both tabular and graphical presentations of the predicted environments at the selected locations can be reviewed by the user. The output includes summaries of rocket-engine operation, ignition overpressure time histories, and one-third octave sound pressure spectra of the predicted launch acoustics. Also, documentation is available to the user to help him or her understand the various aspects of the graphical user interface and the required input parameters.

The thrower's elbow.

PubMed

Patel, Ronak M; Lynch, T Sean; Amin, Nirav H; Calabrese, Gary; Gryzlo, Stephen M; Schickendantz, Mark S

2014-07-01

Overhead throwing activities expose the elbow to tremendous valgus stress, making athletes vulnerable to a specific constellation of injuries. Although baseball players, in particular pitchers, are the athletes affected most commonly, overhead throwing athletes in football, volleyball, tennis, and javelin tossing also are affected. The purpose of this review is to review the anatomy, biomechanics, pathophysiology, and treatment of elbow disorders related to overhead throwing athletes. Although focus is on management of ulnar collateral ligament injuries, all common pathologies are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

Launch summary for 1980

NASA Technical Reports Server (NTRS)

Vostreys, R. W.

1981-01-01

Sounding rockets, artificial Earth satellites, and space probes launched betweeen January 1 and December 31, 1980 are listed. Data tabulated for the rocket launchings show launching site, instruments carried, date of launch, agency rocket identification, sponsoring country, experiment discipline, peak altitude, and the experimenter or institution responsible. Tables for satellites and space probes show COSPAR designation, spacecraft name, country, launch date, epoch date, orbit type, apoapsis, periapsis and inclination period. The functions and responsibilities of the World Data Center and the areas of scientific interest at the seven subcenters are defined. An alphabetical listing of experimenters using the sounding rockets is also provided.

Acoustic/infrasonic rocket engine signatures

NASA Astrophysics Data System (ADS)

Tenney, Stephen M.; Noble, John M.; Whitaker, Rodney W.; ReVelle, Douglas O.

2003-09-01

Infrasonics offers the potential of long-range acoustic detection of explosions, missiles and even sounds created by manufacturing plants. The atmosphere attenuates acoustic energy above 20 Hz quite rapidly, but signals below 10 Hz can propagate to long ranges. Space shuttle launches have been detected infrasonically from over 1000 km away and the Concorde airliner from over 400 km. This technology is based on microphones designed to respond to frequencies from .1 to 300 Hz that can be operated outdoors for extended periods of time with out degrading their performance. The US Army Research Laboratory and Los Alamos National Laboratory have collected acoustic and infrasonic signatures of static engine testing of two missiles. Signatures were collected of a SCUD missile engine at Huntsville, AL and a Minuteman engine at Edwards AFB. The engines were fixed vertically in a test stand during the burn. We will show the typical time waveform signals of these static tests and spectrograms for each type. High resolution, 24-bit data were collected at 512 Hz and 16-bit acoustic data at 10 kHz. Edwards data were recorded at 250 Hz and 50 Hz using a Geotech Instruments 24 bit digitizer. Ranges from the test stand varied from 1 km to 5 km. Low level and upper level meteorological data was collected to provide full details of atmospheric propagation during the engine test. Infrasonic measurements were made with the Chaparral Physics Model 2 microphone with porous garden hose attached for wind noise suppression. A B&K microphone was used for high frequency acoustic measurements. Results show primarily a broadband signal with distinct initiation and completion points. There appear to be features present in the signals that would allow identification of missile type. At 5 km the acoustic/infrasonic signal was clearly present. Detection ranges for the types of missile signatures measured will be predicted based on atmospheric modeling. As part of an experiment conducted by ARL, sounding rocket launches have been detected from over 150 km. A variety of rockets launched from NASA"s Wallops Island facility were detected over a two year span. Arrays of microphones were able to create a line of bearing to the source of the launches that took place during different times of the year. This same experiment has been able to detect the space shuttle from over 1000 km on a regular basis. These two sources represent opposite ends of the target size, but they do demonstrate the potential for the detection and location of rocket launches.

The Joint Astrophysical Plasmadynamic Experiment (J-PEX): a high-resolution rocket spectrometer

NASA Astrophysics Data System (ADS)

Barstow, Martin A.; Bannister, Nigel P.; Cruddace, Raymond G.; Kowalski, Michael P.; Wood, Kent S.; Yentis, Daryl J.; Gursky, Herbert; Barbee, Troy W., Jr.; Goldstein, William H.; Kordas, Joseph F.; Fritz, Gilbert G.; Culhane, J. Leonard; Lapington, Jonathan S.

2003-02-01

We report on the successful sounding rocket flight of the high resolution (R=3000-4000) J-PEX EUV spectrometer. J-PEX is a novel normal incidence instrument, which combines the focusing and dispersive elements of the spectrometer into a single optical element, a multilayer-coated grating. The high spectral resolution achieved has had to be matched by unprecedented high spatial resolution in the imaging microchannel plate detector used to record the data. We illustrate the performance of the complete instrument through an analysis of the 220-245Å spectrum of the white dwarf G191-B2B obtained with a 300 second exposure. The high resolution allows us to detect a low-density ionized helium component along the line of sight to the star and individual absorption lines from heavier elements in the photosphere.

Reusable Rocket Engine Turbopump Health Management System

NASA Technical Reports Server (NTRS)

Surko, Pamela

1994-01-01

A health monitoring expert system software architecture has been developed to support condition-based health monitoring of rocket engines. Its first application is in the diagnosis decisions relating to the health of the high pressure oxidizer turbopump (HPOTP) of Space Shuttle Main Engine (SSME). The post test diagnostic system runs off-line, using as input the data recorded from hundreds of sensors, each running typically at rates of 25, 50, or .1 Hz. The system is invoked after a test has been completed, and produces an analysis and an organized graphical presentation of the data with important effects highlighted. The overall expert system architecture has been developed and documented so that expert modules analyzing other line replaceable units may easily be added. The architecture emphasizes modularity, reusability, and open system interfaces so that it may be used to analyze other engines as well.

KSC-08pd1859

NASA Image and Video Library

2008-07-01

CAPE CANAVERAL, Fla. – In the Assembly and Refurbishment Facility at NASA's Kennedy Space Center, a crane is lowered over the aft skirt for the Ares 1-X rocket. The segment is being lifted into a machine shop work stand for drilling modifications. The modifications will prepare it for the installation of the auxiliary power unit controller, the reduced-rate gyro unit, the booster decelerator motors and the booster tumble motors. Ares I is an in-line, two-stage rocket that will transport the Orion crew exploration vehicle to low-Earth orbit. Ares I-X is a test rocket. The Ares I first stage will be a five-segment solid rocket booster based on the four-segment design used for the shuttle. Ares I’s fifth booster segment allows the launch vehicle to lift more weight and reach a higher altitude before the first stage separates from the upper stage, which ignites in midflight to propel the Orion spacecraft to Earth orbit. Photo credit: NASA/Jim Grossmann

Toroidal varied-line space (TVLS) gratings

NASA Astrophysics Data System (ADS)

Thomas, Roger J.

2003-02-01

It is a particular challenge to develop a stigmatic spectrograph for EUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both re-imaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-space rulings (TULS). A number of solar EUV spectrographs have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets SERTS and EUNIS. More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. These ideas are now combined into a spectrograph concept that considers varied-line space grooves ruled onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of two solar spectrographs based on this concept are described: SUMI, proposed as a sounding rocket experiment, and NEXUS, proposed for the Solar Dynamics Observatory mission.

Toroidal Varied-Line Space (TVLS) Gratings

NASA Technical Reports Server (NTRS)

Thomas, Roger J.; Oegerle, William (Technical Monitor)

2002-01-01

It is a particular challenge to develop a stigmatic spectrograph for XUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both re-imaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-spaced rulings (TULS). A number of solar EUV (Extreme Ultraviolet) spectrometers have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets SERTS and EUNIS. More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. We now combine these ideas into a spectrometer concept that puts varied-line space rulings onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of two solar spectrometers based on this concept are described: SUMI, proposed as a sounding rocket experiment, and NEXUS, proposed for the Solar Dynamics Observatory mission.

Effect of retinal defocus on basketball free throw shooting performance.

PubMed

Bulson, Ryan C; Ciuffreda, Kenneth J; Hayes, John; Ludlam, Diana P

2015-07-01

Vision plays a critical role in athletic performance; however, previous studies have demonstrated that a variety of simulated athletic sensorimotor tasks can be surprisingly resilient to retinal defocus (blurred vision). The purpose of the present study was to extend this work to determine the effect of retinal defocus on overall basketball free throw performance, as well as for the factors gender, refractive error and experience. Forty-four young adult participants of both genders were recruited. They had a range of refractive errors and basketball experience. Each performed 20 standard basketball free throws under five lens defocus conditions in a randomised manner: plano, +1.50 D, +3.00 D, +4.50 D and +10.00 D. Overall, free throw performance was significantly reduced under the +10.00 D lens defocus condition only. Previous experience, but neither refractive error nor gender, yielded a statistically significant difference in performance. Consistent with previous studies of complex sensorimotor tasks, basketball free throw performance was resilient to low and moderate levels of retinal defocus. Thus, for a relatively non-dynamic motor task at a fixed far distance, such as the basketball free throw, precise visual clarity was not critical. Other factors such as motor memory may be important. However, in the dynamic athletic competitive environment it is likely that visual clarity plays a more critical role in one's performance level, at least for specific task demands. © 2015 The Authors. Clinical and Experimental Optometry © 2015 Optometry Australia.

Effect of core stability training on throwing velocity in female handball players.

PubMed

Saeterbakken, Atle H; van den Tillaar, Roland; Seiler, Stephen

2011-03-01

The purpose was to study the effect of a sling exercise training (SET)-based core stability program on maximal throwing velocity among female handball players. Twenty-four female high-school handball players (16.6 ± 0.3 years, 63 ± 6 kg, and 169 ± 7 cm) participated and were initially divided into a SET training group (n = 14) and a control group (CON, n = 10). Both groups performed their regular handball training for 6 weeks. In addition, twice a week, the SET group performed a progressive core stability-training program consisting of 6 unstable closed kinetic chain exercises. Maximal throwing velocity was measured before and after the training period using photocells. Maximal throwing velocity significantly increased 4.9% from 17.9 ± 0.5 to 18.8 ± 0.4 m·s in the SET group after the training period (p < 0.01), but was unchanged in the control group (17.1 ± 0.4 vs. 16.9 ± 0.4 m·s). These results suggest that core stability training using unstable, closed kinetic chain movements can significantly improve maximal throwing velocity. A stronger and more stable lumbopelvic-hip complex may contribute to higher rotational velocity in multisegmental movements. Strength coaches can incorporate exercises exposing the joints for destabilization force during training in closed kinetic chain exercises. This may encourage an effective neuromuscular pattern and increase force production and can improve a highly specific performance task such as throwing.

Sleeper stretch accelerates recovery of glenohumeral internal rotation after pitching.

PubMed

Reuther, Katherine E; Larsen, Ryan; Kuhn, Pamela D; Kelly, John D; Thomas, Stephen J

2016-12-01

The natural time course for recovery of glenohumeral internal rotation (IR) loss after a throwing episode is unknown. In addition, the effect of the sleeper stretch on the time course for recovery of motion after a throwing episode has never been investigated. Therefore, the objectives of this study were to (1) to determine the natural time course for spontaneous recovery of IR after a throwing episode and (2) to evaluate the effect of the sleeper stretch on the time course for recovery of IR after a throwing episode. The study participants were 17 male high school baseball pitchers (aged 17.7 ± 0.9 years). A crossover designed was used over a 2-week period. For week 1, glenohumeral IR and external rotation (ER) were evaluated in the dominant shoulder 1 day before a throwing episode and at 2 hours, 1 day, 2 days, 3 days, 4 days, and 5 days after pitching. During week 2, participants completed a sleeper stretch protocol before measurements. The natural time course of spontaneous recovery for IR after a throwing episode was 4 days. Stretching reduced the time course of recovery for IR to 2 days. A sleeper stretch program for high school baseball pitchers can accelerate the recovery of commonly observed IR loss and also may mitigate the cumulative effects observed over the course of a season. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Baseball Throwing Mechanics as They Relate to Pathology and Performance - A Review

PubMed Central

Whiteley, Rod

2007-01-01

It is a commonly held perception amongst biomechanists, sports medicine practitioners, baseball coaches and players, that an individual baseball player's style of throwing or pitching influences their performance and susceptibility to injury. With the results of a series of focus groups with baseball managers and pitching coaches in mind, the available scientific literature was reviewed regarding the contribution of individual aspects of pitching and throwing mechanics to potential for injury and performance. After a discussion of the limitations of kinematic and kinetic analyses, the individual aspects of pitching mechanics are discussed under arbitrary headings: Foot position at stride foot contact; Elbow flexion; Arm rotation; Arm horizontal abduction; Arm abduction; Lead knee position; Pelvic orientation; Deceleration-phase related issues; Curveballs; and Teaching throwing mechanics. In general, popular opinion of baseball coaching staff was found to be largely in concordance with the scientific investigations of biomechanists with several notable exceptions. Some difficulties are identified with the practical implementation of analyzing throwing mechanics in the field by pitching coaches, and with some unquantified aspects of scientific analyses. Key pointsBiomechanical analyses including kinematic and kinetic analyses allow for estimation of pitching performance and potential for injury.Some difficulties both theoretic and practical exist for the implementation and interpretation of such analyses.Commonly held opinions of baseball pitching authorities are largely held to concur with biomechanical analyses.Recommendations can be made regarding appropriate pitching and throwing technique in light of these investigations. PMID:24149219

Experimental investigation of solid rocket motors for small sounding rockets

NASA Astrophysics Data System (ADS)

Suksila, Thada

2018-01-01

Experimentation and research of solid rocket motors are important subjects for aerospace engineering students. However, many institutes in Thailand rarely include experiments on solid rocket motors in research projects of aerospace engineering students, mainly because of the complexity of mixing the explosive propellants. This paper focuses on the design and construction of a solid rocket motor for total impulse in the class I-J that can be utilised as a small sounding rocket by researchers in the near future. Initially, the test stands intended for measuring the pressure in the combustion chamber and the thrust of the solid rocket motor were designed and constructed. The basic design of the propellant configuration was evaluated. Several formulas and ratios of solid propellants were compared for achieving the maximum thrust. The convenience of manufacturing and casting of the fabricated solid rocket motors were a critical consideration. The motor structural analysis such as the combustion chamber wall thickness was also discussed. Several types of nozzles were compared and evaluated for ensuring the maximum thrust of the solid rocket motors during the experiments. The theory of heat transfer analysis in the combustion chamber was discussed and compared with the experimental data.

Turbopump Design and Analysis Approach for Nuclear Thermal Rockets

NASA Technical Reports Server (NTRS)

Chen, Shu-cheng S.; Veres, Joseph P.; Fittje, James E.

2006-01-01

A rocket propulsion system, whether it is a chemical rocket or a nuclear thermal rocket, is fairly complex in detail but rather simple in principle. Among all the interacting parts, three components stand out: they are pumps and turbines (turbopumps), and the thrust chamber. To obtain an understanding of the overall rocket propulsion system characteristics, one starts from analyzing the interactions among these three components. It is therefore of utmost importance to be able to satisfactorily characterize the turbopump, level by level, at all phases of a vehicle design cycle. Here at NASA Glenn Research Center, as the starting phase of a rocket engine design, specifically a Nuclear Thermal Rocket Engine design, we adopted the approach of using a high level system cycle analysis code (NESS) to obtain an initial analysis of the operational characteristics of a turbopump required in the propulsion system. A set of turbopump design codes (PumpDes and TurbDes) were then executed to obtain sizing and performance characteristics of the turbopump that were consistent with the mission requirements. A set of turbopump analyses codes (PUMPA and TURBA) were applied to obtain the full performance map for each of the turbopump components; a two dimensional layout of the turbopump based on these mean line analyses was also generated. Adequacy of the turbopump conceptual design will later be determined by further analyses and evaluation. In this paper, descriptions and discussions of the aforementioned approach are provided and future outlooks are discussed.

Development of partial rock veneers by root throw in a subalpine setting

USGS Publications Warehouse

Osterkamp, W.R.; Toy, T.J.; Lenart, M.T.

2006-01-01

Rock veneers stabilize hillslope surfaces, occur especially in areas of immature soil, and form through a variety of process sets that includes root throw. Near Westcliffe, Colorado, USA, data were collected from a 20 ?? 500 m transect on the east slope of the Sangre de Cristo Mountains. Ages of pit/mound complexes with rock fragments exposed at the surface by root throw ranged from recent (freshly toppled tree) to unknown (complete tree decay). Calculations based on dimensions of the pit/mound complexes, estimated time of free topppling, sizes of exposed rock fragments, and percentage rock covers at pit/mound complexes, as well as within the transect area, indicate that recent rates of root throw have resulted in only partial rock veneering since late Pleistocene deglaciation. Weathering of rock fragments prevent development of an extensive rock veneer and causes a balance, achieved within an estimated 700 years, between the rates of rock-fragment exposure by root throw and clast disintegration by chemical reduction. The estimated rate of rock-fragment reduction accounts for part of the fluvial sediment yields observed for forested subalpine areas of western North America. Copyright ?? 2005 John Wiley & Sons, Ltd.

Sequence-dependent rotation axis changes and interaction torque use in overarm throwing.

PubMed

Hansen, Clint; Rezzoug, Nasser; Gorce, Philippe; Venture, Gentiane; Isableu, Brice

2016-01-01

We examined the role of rotation axes during an overarm throwing task. Participants performed such task and were asked to throw a ball at maximal velocity at a target. The purpose of this study was to examine whether the minimum inertia axis would be exploited during the throwing phases, a time when internal-external rotations of the shoulder are particularly important. A motion capture system was used to evaluate the performance and to compute the potential axes of rotation (minimum inertia axis, shoulder-centre of mass axis and the shoulder-elbow axis). More specifically, we investigated whether a velocity-dependent change in rotational axes can be observed in the different throwing phases and whether the control obeys the principle of minimum inertia resistance. Our results showed that the limbs' rotational axis mainly coincides with the minimum inertia axis during the cocking phase and with the shoulder-elbow axis during the acceleration phase. Besides these rotation axes changes, the use of interaction torque is also sequence-dependent. The sequence-dependent rotation axes changes associated with the use of interaction torque during the acceleration phase could be a key factor in the production of hand velocity at ball release.

Development of a Polarimeter for Magnetic Field Measurements in the Ultraviolet

NASA Technical Reports Server (NTRS)

West, Edward; Porter, Jason; Davis, John; Gary, Allen; Adams, Mitzi; Rose, M. Franklin (Technical Monitor)

2001-01-01

This paper will describe the polarizing optics that are being developed for an ultraviolet magnetograph (SUMI) which will be flown on a sounding rocket payload. With a limited observing program, the polarizing optics were optimized to make simultaneous observation at two magnetic lines CIV (155nm) and MgII (280). This paper will give a brief overview of the SUMI instrument, will describe the polarimeter that will be used in the sounding rocket program and will present some of the measurements that have been made on the (SUMI) polarization optics.

Solid propellant processing factor in rocket motor design

NASA Technical Reports Server (NTRS)

1971-01-01

The ways are described by which propellant processing is affected by choices made in designing rocket engines. Tradeoff studies, design proof or scaleup studies, and special design features are presented that are required to obtain high product quality, and optimum processing costs. Processing is considered to include the operational steps involved with the lining and preparation of the motor case for the grain; the procurement of propellant raw materials; and propellant mixing, casting or extrusion, curing, machining, and finishing. The design criteria, recommended practices, and propellant formulations are included.

GLENOHUMERAL MOTION DEFICITS: FRIEND OR FOE?

PubMed Central

Wilk, Kevin E.; Davies, George; Ellenbecker, Todd; Reinold, Mike

2013-01-01

In most shoulder conditions a loss of glenohumeral motion results in shoulder performance impairments. However, in the overhead athlete loss of glenohumeral internal rotation, termed glenohumeral internal rotation deficiency (GIRD), is a normal phenomenon that should be expected. Without a loss of glenohumeral internal rotation the overhead athlete will not have the requisite glenohumeral external rotation needed to throw a baseball at nearly 100 miles per hour, or serve a tennis ball at velocities of 120 miles per hour or more. Not all GIRD is pathologic. The authors of this manuscript have defined two types of GIRD; one that is normal and one that is pathologic. Anatomical GIRD (aGIRD) is one that is normal in overhead athletes and is characterized by a loss of internal rotation of less than 18°‐20° with symmetrical total rotational motion (TROM) bilaterally. Pathologic GIRD (pGIRD) is when there is a loss of glenohumeral internal rotation greater than 18°‐20° with a corresponding loss of TROM greater than 5° when compared bilaterally. A more problematic motion restriction may be that of a loss of TROM in the glenohumeral joint. Recent evidence supports that a loss of TROM is predictive of future injury to the shoulder in professional athletes. Additionally, external rotation deficiency (ERD), the difference between external rotation (ER) of the throwing shoulder and the non‐throwing shoulder of less than 5°, may be another predictor of future shoulder injury and disability. Level of Evidence: 5 PMID:24175137

75 FR 20874 - Agency Information Collection Activity Seeking OMB Approval

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-21

... to issue Experimental Permits for reusable suborbital rockets to authorize launches for the purpose... Suborbital Rockets. Type of Request: Extension without change of a currently approved collection. OMB Control... FAA's new authority to issue Experimental Permits for reusable [[Page 20875

ARC-2009-ACD09-0144-035

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-065

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-080

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-047

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-089

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-096

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-094

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-091

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-051

NASA Image and Video Library

2009-07-19

MoonFest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-063

NASA Image and Video Library

2009-07-19

Moonfest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

ARC-2009-ACD09-0144-021

NASA Image and Video Library

2009-07-19

Moonfest: From Apollo to LCROSS and Beyond public event at NASA'S Ames Researc Center, Moffett Field, Calif. The day included scientific talks, model rocket launches on the flight line, musical performances, family-friendly activities and more.

The Marshall Grazing Incidence X-ray Spectrometer

NASA Astrophysics Data System (ADS)

Kobayashi, Ken; Winebarger, Amy R.; Savage, Sabrina; Champey, Patrick; Cheimets, Peter N.; Hertz, Edward; Bruccoleri, Alexander R.; Golub, Leon; Ramsey, Brian; Ranganathan, Jaganathan; Marquez, Vanessa; Allured, Ryan; Parker, Theodore; Heilmann, Ralf K.; Schattenburg, Mark L.

2017-08-01

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a NASA sounding rocket instrument designed to obtain spatially resolved soft X-ray spectra of the solar atmosphere in the 6-24 Å (0.5-2.0 keV) range. The instrument consists of a single shell Wolter Type-I telescope, a slit, and a spectrometer comprising a matched pair of grazing incidence parabolic mirrors and a planar varied-line space diffraction grating. The instrument is designed to achieve a 50 mÅ spectral resolution and 5 arcsecond spatial resolution along a +/-4-arcminute long slit, and launch is planned for 2019. We report on the status and our approaches for fabrication and alignment for this novel optical system. The telescope and spectrometer mirrors are replicated nickel shells, and are currently being fabricated at the NASA Marshall Space Flight Center. The diffraction grating is currently under development by the Massachusetts Institute of Technology (MIT); because of the strong line spacing variation across the grating, it will be fabricated through e-beam lithography.

Closed-kinetic chain upper-body training improves throwing performance of NCAA Division I softball players.

PubMed

Prokopy, Max P; Ingersoll, Christopher D; Nordenschild, Edwin; Katch, Frank I; Gaesser, Glenn A; Weltman, Arthur

2008-11-01

Closed-kinetic chain resistance training (CKCRT) of the lower body is superior to open-kinetic chain resistance training (OKCRT) to improve performance parameters (e.g., vertical jump), but the effects of upper-body CKCRT on throwing performance remain unknown. This study compared shoulder strength, power, and throwing velocity changes in athletes training the upper body exclusively with either CKCRT (using a system of ropes and slings) or OKCRT. Fourteen female National Collegiate Athletic Association Division I softball player volunteers were blocked and randomly placed into two groups: CKCRT and OKCRT. Blocking ensured the same number of veteran players and rookies in each training group. Training occurred three times weekly for 12 weeks during the team's supervised off-season program. Olympic, lower-body, core training, and upper-body intensity and volume in OKCRT and CKCRT were equalized between groups. Criterion variables pre- and posttraining included throwing velocity, bench press one-repetition maximum (1RM), dynamic single-leg balance, and isokinetic peak torque and power (PWR) (at 180 degrees x s(-1)) for shoulder flexion, extension, internal rotation, and external rotation (ER). The CKCRT group significantly improved throwing velocity by 2.0 mph (3.4%, p < 0.05), and the OKCRT group improved 0.3 mph (0.5%, NS). A significant interaction was observed (p < 0.05). The CKCRT group improved its 1RM bench press to the same degree (1.9 kg) as the OKCRT group (p < 0.05 within each group). The CKCRT group improved all measures of shoulder strength and power, whereas OKCRT conferred little change in shoulder torque and power scores. Although throwing is an open-chain movement, adaptations from CKCRT may confer benefits to subsequent performance. Strength coaches can incorporate upper-body CKCRT without sacrificing gains in maximal strength or performance criteria associated with an athletic open-chain movement such as throwing.

Altitude-Compensating Nozzle (ACN) Project: Planning for Dual-Bell Rocket Nozzle Flight Testing on the NASA F-15B

NASA Technical Reports Server (NTRS)

Jones, Daniel S.; Bui, Trong T.; Ruf, Joseph H.

2013-01-01

For more than a half-century, several types of altitude-compensating nozzles have been proposed and analyzed, but very few have been adequately tested in a relevant flight environment. One type of altitude-compensating nozzle is the dual-bell rocket nozzle, which was first introduced into literature in 1949. Although the dual-bell rocket nozzle has been thoroughly studied, this nozzle has still not been tested in a relevant flight environment. This poster presents the top-level rationale and preliminary plans for conducting flight research with the dual-bell rocket nozzle, while exhausting the plume into the freestream flow field at various altitudes. The primary objective is to gain a greater understanding of the nozzle plume sensitivity to freestream flight effects, which will also include detailed measurements of the plume mode transition within the nozzle. To accomplish this goal, the NASA F-15B is proposed as the testbed for advancing the technology readiness level of this greatly-needed capability. All proposed tests include the quantitative performance analysis of the dual-bell rocket nozzle as compared with the conventional-bell nozzle.

Read the Label First! Protect Your Pets

MedlinePlus

... important information about the product. ✔ Keep Products in Original Containers • It is very dangerous to put products ... to the product. • If you throw away the original container, you throw away important information needed in ...

Read the Label First! Protect Your Household

MedlinePlus

... as directed on the label. ✔ Keep Products in Original Containers • It is very dangerous to put products ... about the product. • If you throw away the original container, you throw away important information needed in ...

Integrating fundamental movement skills in late childhood.

PubMed

Gimenez, Roberto; Manoel, Edison de J; de Oliveira, Dalton Lustosa; Dantas, Luiz; Marques, Inara

2012-04-01

The study examined how children of different ages integrate fundamental movement skills, such as running and throwing, and whether their developmental status was related to the combination of these skills. Thirty children were divided into three groups (G1 = 6-year-olds, G2 = 9-year-olds, and G3 = 12-year-olds) and filmed performing three tasks: running, overarm throwing, and the combined task. Patterns were identified and described, and the efficiency of integration was calculated (distance differences of the ball thrown in two tasks, overarm throwing and combined task). Differences in integration were related to age: the 6-year-olds were less efficient in combining the two skills than the 9- and 12-year-olds. These differences may be indicative of a phase of integrating fundamental movement skills in the developmental sequence. This developmental status, particularly throwing, seems to be related to the competence to integrate skills, which suggests that fundamental movement skills may be developmental modules.

Damage-mitigating control of a reusable rocket engine for high performance and extended life

NASA Technical Reports Server (NTRS)

Ray, Asok; Dai, Xiaowen

1995-01-01

The goal of damage mitigating control in reusable rocket engines is to achieve high performance with increased durability of mechanical structures such that functional lives of the critical components are increased. The major benefit is an increase in structural durability with no significant loss of performance. This report investigates the feasibility of damage mitigating control of reusable rocket engines. Phenomenological models of creep and thermo-mechanical fatigue damage have been formulated in the state-variable setting such that these models can be combined with the plant model of a reusable rocket engine, such as the Space Shuttle Main Engine (SSME), for synthesizing an optimal control policy. Specifically, a creep damage model of the main thrust chamber wall is analytically derived based on the theories of sandwich beam and viscoplasticity. This model characterizes progressive bulging-out and incremental thinning of the coolant channel ligament leading to its eventual failure by tensile rupture. The objective is to generate a closed form solution of the wall thin-out phenomenon in real time where the ligament geometry is continuously updated to account for the resulting deformation. The results are in agreement with those obtained from the finite element analyses and experimental observation for both Oxygen Free High Conductivity (OFHC) copper and a copper-zerconium-silver alloy called NARloy-Z. Due to its computational efficiency, this damage model is suitable for on-line applications of life prediction and damage mitigating control, and also permits parametric studies for off-line synthesis of damage mitigating control systems. The results are presented to demonstrate the potential of life extension of reusable rocket engines via damage mitigating control. The control system has also been simulated on a testbed to observe how the damage at different critical points can be traded off without any significant loss of engine performance. The research work reported here is built upon concepts derived from the disciplines of Controls, Thermo-fluids, Structures, and Materials. The concept of damage mitigation, as presented in this report, is not restricted to control of rocket engines. It can be applied to any system where structural durability is an important issue.

Welded Titanium Case for Space-Probe Rocket Motor

NASA Technical Reports Server (NTRS)

Brothers, A. J.; Boundy, R. A.; Martens, H. E.; Jaffe, L. D.

1959-01-01

The high strength-to-weight ratio of titanium alloys suggests their use for solid-propellant rocket-motor cases for high-performance orbiting or space-probe vehicles. The paper describes the fabrication of a 6-in.-diam., 0.025-in.-wall rocket-motor from the 6A1-4V titanium alloy. The rocket-motor case, used in the fourth stage of a successful JPL-NASA lunar-probe flight, was constructed using a design previously proven satisfactory for Type 410 stainless steel. The nature and scope of the problems peculiar to the use of the titanium alloy, which effected an average weight saving of 34%, are described.

Technical Advisory Team (TAT) report on the rocket sled test accident of October 9, 2008.

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

Stofleth, Jerome H.; Dinallo, Michael Anthony; Medina, Anthony J.

2009-01-01

This report summarizes probable causes and contributing factors that led to a rocket motor initiating prematurely while employees were preparing instrumentation for an AIII rocket sled test at SNL/NM, resulting in a Type-B Accident. Originally prepared by the Technical Advisory Team that provided technical assistance to the NNSA's Accident Investigation Board, the report includes analyses of several proposed causes and concludes that the most probable source of power for premature initiation of the rocket motor was the independent battery contained in the HiCap recorder package. The report includes data, evidence, and proposed scenarios to substantiate the analyses.

Measurements of the Magnetic Field of the Upper Chromosphere with Polarimetry

NASA Technical Reports Server (NTRS)

Rachmeler, Laurel; Mckenzie, David; Winebarger, Amy; Kobayashi, Ken; Ishikawa, Ryohko; Kubo, Masahito; Narukage, Noriyuki; Bueno, Trujillo, Javier; Auchere, Frederic

2017-01-01

A major remaining challenge for heliophysics is to decipher the magnetic structure of the chromosphere. The chromosphere is the critical interface between the Sun's photosphere and corona: it contains more mass than the entire interplanetary heliosphere, requires a heating rate that is larger than that of the corona, and mediates all the energy driving the solar wind, solar atmospheric heating and solar eruptions. While measurements of the magnetic field in the photosphere are routine, the chromosphere poses several extra challenges. The magnetically sensitive lines formed in the upper chromosphere are in the ultraviolet, so space-based observations are required. The lines are often formed over a range of heights, sampling different plasma which complicates the inversion process. These lines are sensitive to the magnetic field via polarized light that is created or modified through the Hanle and Zeeman effects. There are a few observations of these lines, and a significant challenge remains in extracting the magnetic field from the polarization measurements, as detailed model atmospheres with advanced radiative transfer physics are needed. Real progress is obtained by a simultaneous improvement in both the observational side and the modeling side. We present information on the CLASP (Chromospheric LAyer Spectro-Polarimeter) sounding rocket program, and future prospects for these types of measurements.

Labeled line drawing of Magellan spacecraft

NASA Technical Reports Server (NTRS)

1988-01-01

Labeled line drawing identifies Magellan spacecraft components including forward equipment module, star scanner, propulsion module, rocket engine module, thermal control louvers, solar panel drive and cable wrap, solar panel, bus, altimeter antenna, low-gain antenna, and high gain antenna. Magellan, named for the 16th century Portuguese explorer, will be deployed from the payload bay (PLB) of Atlantis, Orbiter Vehicle (OV) 104, during mission STS-30.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

Team members prepare the Advanced Base Line Imager, the primary optical instrument, for installation on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

Team members install the Advanced Base Line Imager, the primary optical instrument, on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

The Advanced Base Line Imager, the primary optical instrument, has been installed on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Multi-body dynamic coupling mechanism for generating throwing arm velocity during baseball pitching.

PubMed

Naito, Kozo; Takagi, Tokio; Kubota, Hideaki; Maruyama, Takeo

2017-08-01

The purpose of this study was to identify the detailed mechanism how the maximum throwing arm endpoint velocity is determined by the muscular torques and non-muscular interactive torques from the perspective of the dynamic coupling among the trunk, thorax and throwing and non-throwing arm segments. The pitching movements of ten male collegiate baseball pitchers were measured by a three-dimensional motion capture system. Using the induced-segmental velocity analysis (IVA) developed in this study, the maximum fingertip velocity of the throwing arm (MFV) was decomposed into each contribution of the muscular torques, passive motion-dependent torques due to gyroscopic moment, Coriolis force and centrifugal force, and other interactive torque components. The results showed that MFV (31.6±1.7m/s) was mainly attributed to two different mechanisms. The first is the passive motion-dependent effect on increasing the angular velocities of three joints (thorax rotation, elbow extension and wrist flexion). The second is the muscular torque effect of the shoulder internal rotation (IR) torque on generating IR angular velocity. In particular, the centrifugal force-induced elbow extension motion, which was the greatest contributor among individual joint contributions, was caused primarily by the angular velocity-dependent forces associated with the humerus, thorax, and trunk rotations. Our study also found that a compensatory mechanism was achieved by the negative and positive contributions of the muscular torque components. The current IVA is helpful to understand how the rapid throwing arm movement is determined by the dynamic coupling mechanism. Copyright © 2017 Elsevier B.V. All rights reserved.

On-the-Field Resistance-Tubing Exercises for Throwers: An Electromyographic Analysis

PubMed Central

Myers, Joseph B; Pasquale, Maria R; Laudner, Kevin G; Sell, Timothy C; Bradley, James P; Lephart, Scott M

2005-01-01

Context: Athletes who throw commonly use rubber-tubing resistance exercises in the field setting to assist with warm-up before throwing. Yet no researchers have described which muscles are being activated or which exercises are most effective during rubber-tubing exercises used by throwers for warm-up. Objective: To describe the effectiveness of 12 rubber-tubing resistance exercises commonly used by throwers in activating the shoulder muscles important for throwing. Design: Descriptive research design. Setting: An applied biomechanics research laboratory. Patients or Other Participants: Fifteen physically active male subjects with no history of shoulder injury. Main Outcome Measure(s): Subjects randomly performed 12 rubber-tubing resistance exercises while we assessed muscle activation of the subscapularis, supraspinatus, teres minor, and rhomboid major by indwelling electromyography. Activation of the sternal portion of the pectoralis major, anterior deltoid, middle deltoid, latissimus dorsi, serratus anterior, biceps brachii, triceps brachii, lower trapezius, and infraspinatus muscles was assessed by surface electromyography. Results: Performance of 7 exercises (external rotation at 90° of abduction, throwing deceleration, humeral flexion, humeral extension, low scapular rows, throwing acceleration, and scapular punch) resulted in the highest level of muscle activation of all muscles tested. Conclusions: These 7 exercises exhibited moderate activation (>20% maximal voluntary isometric contraction) in each muscle of the rotator cuff, the primary humeral movers, and the scapular stabilizer muscles. The results suggest that these exercises are most effective in activating the muscles important to the throwing motion and may be beneficial for throwers during their prethrowing warm-up routine. PMID:15902319

Porous Ceramic Composite ZrO2(MgO)-MgO for Osteoimplantology

NASA Astrophysics Data System (ADS)

Buyakov, A. S.; Kulkov, S. N.

2017-02-01

Pore and crystalline structure, biocompatibility of ceramic composite ZrO2(MgO)-MgO were studied. The main mechanical characteristics were determined and it has been shown that compression strength directly depends on microstresses obtained from X-ray data. In-vitro studies of mesenchymal stromal stem cells (MMSC), cultivated on material surface are shown that cell proliferation and differentiation of MMSC goes throw osteogenic type.

The Effect of Different Goals and Self-Recording on Self-Regulation of Learning a Motor Skill in a Physical Education Setting

ERIC Educational Resources Information Center

Kolovelonis, Athanasios; Goudas, Marios; Dermitzaki, Irini

2011-01-01

This study examined the effect of different goals (process, performance outcome, and multiple goals) and self-recording on self-regulation of learning a dart-throwing skill. Participants were 105 fifth and sixth graders who were randomly assigned to six (3 Goal type x 2 self-recording) experimental and one control group. Results showed a positive…

Rocket observations of the ultraviolet airglow during morning twilight

NASA Technical Reports Server (NTRS)

Cebula, R. P.; Feldman, P. D.

1984-01-01

Rocket-borne (Astrobee) UV measurements were made of the terrestrial airglow at morning twilight from 82 and 90 deg zenith angles at altitudes of 90 and 246 km in September 1979. Data were acquired on the NO gamma and delta bands, the 2470 A O II, 1356 A and the 1304 A O I lines, the Lyman-Berge-Hopfield N2 and the Herzberg 02 lines. The zodiacal contribution was substracted to obtain pure airglow data. Spectral analyses supported a larger nighttime decrease of N(4S) than for NO, the latter being in diffusive equilibrium above 190 km altitude. The NO gamma band was directly related to the thermospheric N(4S) contribution, the latter having a density of 2-8 million/cu cm at 200 km. Finally, self-consistent photoionization and photoelectron impact ionization models were derived for the atomic and ionic oxygen emissions.

Rocket studies of solar corona and transition region. [X-Ray spectrometer/spectrograph telescope

NASA Technical Reports Server (NTRS)

Acton, L. W.; Bruner, E. C., Jr.; Brown, W. A.; Nobles, R. A.

1979-01-01

The XSST (X-Ray Spectrometer/Spectrograph Telescope) rocket payload launched by a Nike Boosted Black Brant was designed to provide high spectral resolution coronal soft X-ray line information on a spectrographic plate, as well as time resolved photo-electric records of pre-selected lines and spectral regions. This spectral data is obtained from a 1 x 10 arc second solar region defined by the paraboloidal telescope of the XSST. The transition region camera provided full disc images in selected spectral intervals originating in lower temperature zones than the emitting regions accessible to the XSST. A H-alpha camera system allowed referencing the measurements to the chromospheric temperatures and altitudes. Payload flight and recovery information is provided along with X-ray photoelectric and UV flight data, transition camera results and a summary of the anomalies encountered. Instrument mechanical stability and spectrometer pointing direction are also examined.

Analysis of magnesium XI line profiles from solar active regions

NASA Technical Reports Server (NTRS)

Blake, R. L.; Cowan, R. D.; Felthauser, H.; Fenimore, E. E.; Hockaday, M. P.; Bely-Dubau, F.; Faucher, P.; Steenman-Clark, L.

1984-01-01

High-resolution solar spectra of the Mg XI 1s2 1S0-1s2p 1P1 resonance line at 9.169 A and the associated nearby satellite lines obtained from two rocket-borne crystal spectrometer measurements are presented. Comparisons with two independent sets of theoretical calculations for the 1s2nl-1s2pnl dielectronic satellite lines with n = 3-7 indicate electron temperatures of 4-4.5 million K. Measured line widths indicate either that the ion temperature exceeds the electron temperature by about a million K or that about 28 km/s of turbulence is present.

Turbopump systems for liquid rocket engines

NASA Technical Reports Server (NTRS)

1974-01-01

The turbopump system, from preliminary design through rocket engine testing is examined. Selection of proper system type for each application and integration of the components into a working system are dealt with. Details are also given on the design of various components including inducers, pumps, turbines, gears, and bearings.

KSC-00pp0704

NASA Image and Video Library

2000-05-25

At Launch Pad 36A, Cape Canaveral Air Force Station, lines help guide the ascent of a Centaur rocket up the launch tower where it will be mated with the lower stage Atlas IIA rocket already in the tower. The Lockheed-built Atlas IIA/Centaur rocket will launch the latest Tracking and Data Relay Satellite (TDRS) June 29 from CCAFS. The TDRS is one of three (labeled H, I and J) being built in the Hughes Space and Communications Company Integrated Satellite Factory in El Segundo, Calif. The new satellites will augment the TDRS system’s existing Sand Ku-band frequencies by adding Ka-band capability. TDRS will serve as the sole means of continuous, high-data-rate communication with the space shuttle, with the International Space Station upon its completion, and with dozens of unmanned scientific satellites in low earth orbit

KSC00pp0704

NASA Image and Video Library

2000-05-25

At Launch Pad 36A, Cape Canaveral Air Force Station, lines help guide the ascent of a Centaur rocket up the launch tower where it will be mated with the lower stage Atlas IIA rocket already in the tower. The Lockheed-built Atlas IIA/Centaur rocket will launch the latest Tracking and Data Relay Satellite (TDRS) June 29 from CCAFS. The TDRS is one of three (labeled H, I and J) being built in the Hughes Space and Communications Company Integrated Satellite Factory in El Segundo, Calif. The new satellites will augment the TDRS system’s existing Sand Ku-band frequencies by adding Ka-band capability. TDRS will serve as the sole means of continuous, high-data-rate communication with the space shuttle, with the International Space Station upon its completion, and with dozens of unmanned scientific satellites in low earth orbit

Demand-type gas supply system for rocket borne thin-window proportional counters

NASA Technical Reports Server (NTRS)

Acton, L. W.; Caravalho, R.; Catura, R. C.; Joki, E. G.

1977-01-01

A simple closed loop control system has been developed to maintain the gas pressure in thin-window proportional counters during rocket flights. This system permits convenient external control of detector pressure and system flushing rate. The control system is activated at launch with the sealing of a reference volume at the existing system pressure. Inflight control to plus or minus 2 torr at a working pressure of 760 torr has been achieved on six rocket flights.

About an Element of Human Greatness

NASA Astrophysics Data System (ADS)

Hickam, Homer

2002-01-01

What a grand day that was when Alan Shepard climbed into his Mercury capsule attached to a Redstone rocket-the rocket which would ultimately grow into the greatest rocket ever built, the Saturn V Moon rocket. When I was a boy in Coalwood, WV, my greatest hero, besides my father and my mother, was Huntsville's Dr. Wernher von Braun. After Sputnik was launched in October 1957, the newspapers we received in our little coal camp were filled with stories of how American scientists and engineers were desperately working to catch up in the space race. It was as if the science fiction I had read all my life was coming true. Gradually, I became fascinated by the whole thing. I read every article I could find about the men who built rockets and launched them, and kept myself pinned to the television set for the latest on what they were doing. Dr. von Braun's name was mentioned often. At night before I went to steep, I thought about what he might be doing at that very moment and imagined that he was down at Huntsville or Cape Canaveral high on a gantry, lying on his back like Michelangelo, working with a wrench on the fuel lines of one of his rockets. I started to think about what an adventure it would be to work for him, helping him to build rockets and launching them into space. For all I knew, a man with that much conviction might even form an expedition into space, like Lewis and Clark. Either way, I wanted to be part of his team.

A methodology to study the possible occurrence of chugging in liquid rocket engines during transient start-up

NASA Astrophysics Data System (ADS)

Leonardi, Marco; Nasuti, Francesco; Di Matteo, Francesco; Steelant, Johan

2017-10-01

An investigation on the low frequency combustion instabilities due to the interaction of combustion chamber and feed line dynamics in a liquid rocket engine is carried out implementing a specific module in the system analysis software EcosimPro. The properties of the selected double time lag model are identified according to the two classical assumptions of constant and variable time lag. Module capabilities are evaluated on a literature experimental set up consisting of a combustion chamber decoupled from the upstream feed lines. The computed stability map results to be in good agreement with both experimental data and analytical models. Moreover, the first characteristic frequency of the engine is correctly predicted, giving confidence on the use of the module for the analysis of chugging instabilities. As an example of application, a study is carried out on the influence of the feed lines on the system stability, correctly capturing that the lines extend the stable regime of the combustion chamber and that the propellant domes play a key role in coupling the dynamics of combustion chamber and feed lines. A further example is presented to discuss on the role of pressure growth rate and of the combustion chamber properties on the possible occurrence of chug instability during engine start-up and on the conditions that lead to its damping or growth.

Relationship between accuracy and complexity when learning underarm precision throwing.

PubMed

Valle, Maria Stella; Lombardo, Luciano; Cioni, Matteo; Casabona, Antonino

2018-06-12

Learning precision ball throwing was mostly studied to explore the early rapid improvement of accuracy, with poor attention on possible adaptive processes occurring later when the rate of improvement is reduced. Here, we tried to demonstrate that the strategy to select angle, speed and height at ball release can be managed during the learning periods following the performance stabilization. To this aim, we used a multivariate linear model with angle, speed and height as predictors of changes in accuracy. Participants performed underarm throws of a tennis ball to hit a target on the floor, 3.42 m away. Two training sessions (S1, S2) and one retention test were executed. Performance accuracy increased over the S1 and stabilized during the S2, with a rate of changes along the throwing axis slower than along the orthogonal axis. However, both the axes contributed to the performance changes over the learning and consolidation time. A stable relationship between the accuracy and the release parameters was observed only during S2, with a good fraction of the performance variance explained by the combination of speed and height. All the variations were maintained during the retention test. Overall, accuracy improvements and reduction in throwing complexity at the ball release followed separate timing over the course of learning and consolidation.

The Influence of the ‘Trier Social Stress Test’ on Free Throw Performance in Basketball: An Interdisciplinary Study

PubMed Central

Mascret, Nicolas; Ibáñez-Gijón, Jorge; Bréjard, Vincent; Buekers, Martinus; Casanova, Rémy; Marqueste, Tanguy; Montagne, Gilles; Rao, Guillaume; Roux, Yannick; Cury, François

2016-01-01

The aim of the present study was to explore the relationship between stress and sport performance in a controlled setting. The experimental protocol used to induce stress in a basketball free throw was the Trier Social Stress Test (TSST) and its control condition (Placebo-TSST). Participants (n = 19), novice basketball players but trained sportspersons, were exposed to two counterbalanced conditions in a crossover design. They were equipped with sensors to measure movement execution, while salivary cortisol and psychological state were also measured. The task consisted of two sequences of 40 free throws, one before either the TSST or Placebo-TSST and one after. Physiological and psychological measures evidenced that the TSST induced significant stress responses, whereas the Placebo-TSST did not. Shooting performance remained stable after the TSST but decreased after the Placebo-TSST. We found no effect of the TSST or Placebo-TSST on movement execution. A multivariate model of free throw performance demonstrated that timing, smoothness and explosiveness of the movements are more relevant to account for beginner’s behavior than stress-related physiological and psychological states. We conclude that the TSST is a suitable protocol to induce stress responses in sport context, even though the effects on beginners’ free throw performance and execution are small and complex. PMID:27309715

Comparison of trunk kinematics in trunk training exercises and throwing.

PubMed

Stodden, David F; Campbell, Brian M; Moyer, Todd M

2008-01-01

Strength and conditioning professionals, as well as coaches, have emphasized the importance of training the trunk and the benefits it may have on sport performance and reducing the potential for injury. However, no data on the efficacy of trunk training support such claims. The purpose of this study was to examine the maximum differential trunk rotation and maximum angular velocities of the pelvis and upper torso of participants while they performed 4 trunk exercises (seated band rotations, cross-overs, medicine ball throws, and twisters) and compare these trunk exercise kinematics with the trunk kinematics demonstrated in actual throwing performance. Nine NCAA Division I baseball players participated in this study. Each participant's trunk kinematics was analyzed while he performed 5 repetitions of each exercise in both dominant and nondominant rotational directions. Results indicated maximum differentiated rotation in all 4 trunk exercises was similar to maximum differentiated rotation (approximately 50-60 degrees) demonstrated in throwing performance. Maximum angular velocities of the pelvis and upper torso in the trunk exercises were appreciably slower (approximately 50% or less) than the angular velocities demonstrated during throwing performance. Incorporating trunk training exercises that demonstrate sufficient trunk ranges of motion and velocities into a strength and conditioning program may help to increase ball velocity and/or decrease the risk injury.

The Influence of the 'Trier Social Stress Test' on Free Throw Performance in Basketball: An Interdisciplinary Study.

PubMed

Mascret, Nicolas; Ibáñez-Gijón, Jorge; Bréjard, Vincent; Buekers, Martinus; Casanova, Rémy; Marqueste, Tanguy; Montagne, Gilles; Rao, Guillaume; Roux, Yannick; Cury, François

2016-01-01

The aim of the present study was to explore the relationship between stress and sport performance in a controlled setting. The experimental protocol used to induce stress in a basketball free throw was the Trier Social Stress Test (TSST) and its control condition (Placebo-TSST). Participants (n = 19), novice basketball players but trained sportspersons, were exposed to two counterbalanced conditions in a crossover design. They were equipped with sensors to measure movement execution, while salivary cortisol and psychological state were also measured. The task consisted of two sequences of 40 free throws, one before either the TSST or Placebo-TSST and one after. Physiological and psychological measures evidenced that the TSST induced significant stress responses, whereas the Placebo-TSST did not. Shooting performance remained stable after the TSST but decreased after the Placebo-TSST. We found no effect of the TSST or Placebo-TSST on movement execution. A multivariate model of free throw performance demonstrated that timing, smoothness and explosiveness of the movements are more relevant to account for beginner's behavior than stress-related physiological and psychological states. We conclude that the TSST is a suitable protocol to induce stress responses in sport context, even though the effects on beginners' free throw performance and execution are small and complex.

The Water music of Vanuatu

NASA Astrophysics Data System (ADS)

Truscott, Tadd; Hurd, Randy; Belden, Jesse; Speirs, Nathan; Merritt, Andrew; Allen, John

2017-11-01

Female musicians from the northern islands of Vanuatu (within larger Polynesia) use the water surface as an instrument to create a variety of unique sounds. Water music is often made by a line of performers standing side by side, waist deep in clear island waters. Accompanied by singing, the women work in unison exhibiting several percussive techniques, which include striking the water surface and throwing handfuls of water which scatter into droplets before impacting the surface. Each interaction produces a unique acoustic response corresponding to the air-water-hand interaction. We highlight the connection between water interaction, cavity shape and the resulting sound which was discovered by these people through their own experimentation.

Liquid rocket valve components

NASA Technical Reports Server (NTRS)

1973-01-01

A monograph on valves for use with liquid rocket propellant engines is presented. The configurations of the various types of valves are described and illustrated. Design criteria and recommended practices for the various valves are explained. Tables of data are included to show the chief features of valve components in use on operational vehicles.

FEASIBILITY STUDY OF AIR BEARING ROCKET SLED SLIPPERS

DTIC Science & Technology

a simple self-acting type of bearing can support a typical monorail rocket sled, without contact between the slipper and the rail, at speeds between...slipper bearing is capable of preventing slipper-rail contact over the entire speed range of typical monorail and dual rail sleds. However, the weight and

Si III OV Bright Line of Scattering Polarized Light That Has Been Observed in the CLASP and Its Center-to-Limb Variation

NASA Technical Reports Server (NTRS)

Katsukawa, Yukio; Ishikawa, Ryoko; Kano, Ryohei; Kubo, Masahito; Noriyuki, Narukage; Kisei, Bando; Hara, Hirohisa; Yoshiho, Suematsu; Goto, Motouji; Ishikawa, Shinnosuke;

Development of a Low-cost, FPGA-based, Delay Line Particle Detector for Satellite and Sounding Rocket Applications

NASA Astrophysics Data System (ADS)

Harrington, M.; Kujawski, J. T.; Adrian, M. L.; Weatherwax, A. T.

2013-12-01

Electrons are, by definition, a fundamental, chemical and electromagnetic constituent of any plasma. This is especially true within the partially ionized plasmas of Earth's ionosphere where electrons are a critical component of a vast array of plasma processes. Siena College is working on a novel method of processing information from electron spectrometer anodes using delay line techniques and inexpensive COTS electronics to track the movement of high-energy particles. Electron spectrometers use a variety of techniques to determine where an amplified electron cloud falls onto a collecting surface. One traditional method divides the collecting surface into sectors and uses a single detector for each sector. However, as the angular and spatial resolution increases, so does the number of detectors, increasing power consumption, cost, size, and weight of the system. An alternative approach is to connect each sector with a delay line built within the PCB material which is shielded from cross talk by a flooded ground plane. Only one pair of detectors (e.g., one at each end of the chain) are needed with the delay line technique which is different from traditional delay line detectors which use either Application Specific Integrated Circuits (ASICs) or very fast clocks. In this paper, we report on the implementation and testing of a delay line detector using a low-cost Xilinx FPGA and a thirty-two sector delay system. This Delay Line Detector has potential satellite and rocket flight applications due to its low cost, small size and power efficiency

Relationships Between Parents' Child-Rearing Attitudes and the Jumping and Throwing Performance of Their Preschool Children

ERIC Educational Resources Information Center

Schnabl-Dickey, Elizabeth A.

1977-01-01

Permissive, indulgent home environments (characterized by low disciplinarian, high indulgent, and high protective child-rearing attitudes) were positively associated with superior throwing skill, while increased jumping skill was associated with higher maternal discipline. (MB)

The far-ultraviolet emission spectrum of the K2 III star, Arcturus.

NASA Technical Reports Server (NTRS)

Moos, H. W.; Rottman, G. J.

1972-01-01

A moderate-resolution far-ultraviolet spectrum of the K2 IIIp star Arcturus, obtained with a rocket-borne spectrometer, shows chromospheric emission features. Hydrogen L-alpha and O I (1303 A) are clearly identified. The O I (1304 A) stellar surface brightness is as great or greater than that of the sun. Other metal lines, including those of carbon, are weak compared to the O I line.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

Team members assist as a crane lifts the Advanced Base Line Imager, the primary optical instrument, for installation on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

Team members assist as a crane moves the Advanced Base Line Imager, the primary optical instruments, for installation on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Tether Deployer And Brake

NASA Technical Reports Server (NTRS)

Carroll, Joseph A.; Alexander, Charles M.

1993-01-01

Design concept promises speed, control, and reliability. Scheme for deploying tether provides for fast, free, and snagless payout and fast, dependable braking. Developed for small, expendable tethers in outer space, scheme also useful in laying transoceanic cables, deploying guidance wires to torpedoes and missiles, paying out rescue lines from ship to ship via rockets, deploying antenna wires, releasing communication and power cables to sonobuoys and expendable bathythermographs, and in reeling out lines from fishing rods.

Supercomputer modeling of hydrogen combustion in rocket engines

NASA Astrophysics Data System (ADS)

Betelin, V. B.; Nikitin, V. F.; Altukhov, D. I.; Dushin, V. R.; Koo, Jaye

2013-08-01

Hydrogen being an ecological fuel is very attractive now for rocket engines designers. However, peculiarities of hydrogen combustion kinetics, the presence of zones of inverse dependence of reaction rate on pressure, etc. prevents from using hydrogen engines in all stages not being supported by other types of engines, which often brings the ecological gains back to zero from using hydrogen. Computer aided design of new effective and clean hydrogen engines needs mathematical tools for supercomputer modeling of hydrogen-oxygen components mixing and combustion in rocket engines. The paper presents the results of developing verification and validation of mathematical model making it possible to simulate unsteady processes of ignition and combustion in rocket engines.

On the nature of the fragment environment created by the range destruction or random failure of solid rocket motor casings

NASA Technical Reports Server (NTRS)

Eck, M.; Mukunda, M.

1988-01-01

Given here are predictions of fragment velocities and azimuths resulting from the Space Transportation System Solid Rocket Motor range destruct, or random failure occurring at any time during the 120 seconds of Solid Rocket Motor burn. Results obtained using the analytical methods described showed good agreement between predictions and observations for two specific events. It was shown that these methods have good potential for use in predicting the fragmentation process of a number of generically similar casing systems. It was concluded that coupled Eulerian-Lagrangian calculational methods of the type described here provide a powerful tool for predicting Solid Rocket Motor response.

JANNAF Lessons Learned Panel: Selected Saturn V History

NASA Technical Reports Server (NTRS)

Urquhart, Skip

2010-01-01

Pogo occurs when the natural frequency of a propellant feed line comes close to a readily excited rocket longitudinal structural vibration natural frequency. Maximum Pogo response corresponds to close tuning of the structural and hydraulic frequencies. On Saturn V, accelerations up to 17 g's (Zero To Peak) at the Launch Vehicle/Payload Interface and up to 34 g's at an Engine have been observed. Nicknamed Pogo because it causes the Rocket to stretch and compress like a Pogo stick. First recognized with the Titan II in 1962, Pogo remains a prime consideration in design of launch vehicles today

Crew Access Arm Installation onto Mobile Launcher

NASA Image and Video Library

2018-02-26

Viewed from the 274-foot level mobile launcher (ML), the Orion crew access arm (CAA) is beign installed on the tower. The CAA will support the Space launch System (SLS) rocket at NASA's Kennedy Space Center in Florida. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Crew Access Arm Installation onto Mobile Launcher

NASA Image and Video Library

2018-02-26

Viewed from the 274-foot level mobile launcher (ML), a technician begins installation of the Orion crew access arm (CAA) to the tower. The CAA will support the Space launch System (SLS) rocket at NASA's Kennedy Space Center in Florida. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Crew Access Arm Installation onto Mobile Launcher

NASA Image and Video Library

2018-02-26

Viewed from the 274-foot level mobile launcher (ML), a crane positions the Orion crew access arm (CAA) so it can be attached to the tower that will support the Space launch System (SLS) rocket at NASA's Kennedy Space Center in Florida. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Integration of rocket turbine design and analysis through computer graphics

NASA Technical Reports Server (NTRS)

Hsu, Wayne; Boynton, Jim

1988-01-01

An interactive approach with engineering computer graphics is used to integrate the design and analysis processes of a rocket engine turbine into a progressive and iterative design procedure. The processes are interconnected through pre- and postprocessors. The graphics are used to generate the blade profiles, their stacking, finite element generation, and analysis presentation through color graphics. Steps of the design process discussed include pitch-line design, axisymmetric hub-to-tip meridional design, and quasi-three-dimensional analysis. The viscous two- and three-dimensional analysis codes are executed after acceptable designs are achieved and estimates of initial losses are confirmed.

KSC-08pd3245

NASA Image and Video Library

2008-10-17

CAPE CANAVERAL, Fla. - Workers lift the Ares IX upper stage segments’ ballast assemblies off a truck in high bay 4 of the Vehicle Assembly Building at NASA’s Kennedy Space Center, part of the preparations for the test of the Ares IX rocket. These ballast assemblies will be installed in the upper stage 1 and 7 segments and will mimic the mass of the fuel. Their total weight is approximately 160,000 pounds. The test launch of the Ares IX in 2009 will be the first designed to determine the flight-worthiness of the Ares I rocket. Ares I is an in-line, two-stage rocket that will transport the Orion crew exploration vehicle to low-Earth orbit. The Ares I first stage will be a five-segment solid rocket booster based on the four-segment design used for the space shuttle. Ares I’s fifth booster segment allows the launch vehicle to lift more weight and reach a higher altitude before the first stage separates from the upper stage, which ignites in midflight to propel the Orion spacecraft to Earth orbit. Photo credit: NASA/Kim Shiflett

KSC-08pd3247

NASA Image and Video Library

2008-10-17

CAPE CANAVERAL, Fla. - Workers position Ares IX upper stage segments’ ballast assemblies along the floor of high bay 4 in the Vehicle Assembly Building at NASA’s Kennedy Space Center, part of the preparations for the test of the Ares IX rocket. These ballast assemblies will be installed in the upper stage 1 and 7 segments and will mimic the mass of the fuel. Their total weight is approximately 160,000 pounds. The test launch of the Ares IX in 2009 will be the first designed to determine the flight-worthiness of the Ares I rocket. Ares I is an in-line, two-stage rocket that will transport the Orion crew exploration vehicle to low-Earth orbit. The Ares I first stage will be a five-segment solid rocket booster based on the four-segment design used for the space shuttle. Ares I’s fifth booster segment allows the launch vehicle to lift more weight and reach a higher altitude before the first stage separates from the upper stage, which ignites in midflight to propel the Orion spacecraft to Earth orbit. Photo credit: NASA/Kim Shiflett