String Tension Effects on Tennis Ball Rebound Speed and Accuracy During Playing Conditions
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USTA Parents Guide to 10 and Under Tennis
10 AND UNDER TENNIS A Parents Guide 10andUnderTennis.com little activity, your child is unlikely to develop a love of the game Chapter 1: Introduction and will instead find another activity that is more compelling. Parents want to do what is best for their children. They want to Long-term goals include the enjoyment of an activity they can play provide meaningful and positive experiences that will be enjoyable for a lifetime. It is a game kids can play with friends and family. and lead to the positive development of the child. Tennis is a sport Tennis is a fantastic way to spend quality time as a family. that a child can learn at a young age and enjoy with friends and Be aware of putting pressure on children for results, but make family for a lifetime. This guide will provide you with the right tools sure you recognize and acknowledge effort. In this country, 70 to get your child started correctly, keeping the focus on the fun, percent of kids quit organized sport by the age of 13, and the top active and lifelong benefits of tennis. three reasons given by kids are: Goals 1. It’s not fun anymore It is important to keep participation in youth sports in perspective and 2. Parental pressure to perform to understand why kids play. Many times adults have grand ideas of a 3. Unmet coaching expectations professional career or even a college scholarship. While these could be long-term goals for those players who eventually specialize in a sport, children play for different reasons. -
Ball Change in Tennis: How Does It Affect Match Characteristics and Rally Pace in Grand Slam Tournaments?
Original Article Ball change in tennis: How does it affect match characteristics and rally pace in Grand Slam tournaments? JAN CARBOCH 1 , MATEJ BLAU, MICHAL SKLENARIK, JAKUB SIMAN, KRISTYNA PLACHA Department of Sport Games, Faculty of Physical Education and Sport, Charles University, Prague, Czech Republic ABSTRACT Tennis balls degrade after fast racket and ground impacts until they are changed after agreed number of games. The aim is to analyse the new (after the ball change) and used balls (prior to the ball change) match characteristics and the frequency of rally shots in matches in the Australian Open, French Open and Wimbledon in 2017. Paired samples t-tests and Cohen d were used to compare the point duration, number of rally shots, time between the points, rally pace and work to rest ratio among these tournaments. There was a significant difference in rally shots number played with the new balls (4.17 ± 0.86) compared to the used balls (4.60 ± 1.10) in female matches (p = 0.047); in males matches large effect size was found (d = - 0.83) in the same variable with the new balls (4.44 ± 0.57) and used balls (4.95 ± 0.66), both happened in the Australian Open. No difference was found between the new and used balls in the rally pace in all the observed events. The Wimbledon match characteristics were least affected by the ball change. The ball degradation affected the match characteristic the most in the Australian Open, in terms of more rally shots, but not slowing down the rally pace. -
Influence of Physical Properties of Hockey Stick Blade on Shots
Influence of Physical Properties of Hockey Stick Blade on Shots Martin Plesch1, 2, Samuel Jan´ Plesn´ık3, and Natalia´ Ruˇzickovˇ a´ 4, * 1Institute of Physics, Slovak Academy of Sciences, Bratislava, Slovak Republic 2Institute of Computer Science, Masaryk University, Brno, Czech Republic 3Prve´ Sukromn´ e´ Gymnazium,´ Bratislava, Slovak Republic 4Institute of Science and Technology, Klosterneuburg, Austria *[email protected] ABSTRACT Parameters of a shot of an ice hockey player are mostly determined by the capabilities of the player and the physical properties of the stick used. To reach better performance, every hockey player uses also a hockey tape for an adjustment of the stick blade, that changes both the damping properties as well as the friction coefficient of the blade surface. To show the unexpected extent to which these physical properties of the blade affect the shot, we compared two types of blade cover: traditional tape (rolled onto the blade) and a blade sticker that adheres to both sides of the hockey stick blade. We analysed high-speed recordings of two types of shots by 13 players, ranging from amateurs and junior players to NHL superstars. The two covers differ greatly in friction coefficient and stiffness, which results in significantly (more than 99% confidence) greater speed, rotation and energy when using the stiffer and rougher sticker. 1 Introduction Ice hockey sticks have experienced a gradual development in recent decades. Progress in material science allowed the replacement of widely used wood by composite materials that nowadays represent the standard for hockey players worldwide. Broad usage of new materials like aluminium and composites has become an interesting topic for research as well. -
Learning of Cooperative Actions in Multi-Agent Systems: a Case Study of Pass Play in Soccer Hitoshi Matsubara, Itsuki Noda and Kazuo Hiraki
From: AAAI Technical Report SS-96-01. Compilation copyright © 1996, AAAI (www.aaai.org). All rights reserved. Learning of Cooperative actions in multi-agent systems: a case study of pass play in Soccer Hitoshi Matsubara, Itsuki Noda and Kazuo Hiraki Electrotechnical Laboratory 1-1-4 Umezono, Tsukuba, Ibaraki, 305 JAPAN e-maih {matsubar, noda, khiraki} @etl.go.jp Abstract Fromthe standpoint of multi-agent systems, soccer (association football), whichis just one of usual team sports, makea good example of problems in the real world which is moderately abstracted. Wehave cho- sen soccer as one of standard problems for the study on multi-agent systems, and we are now developing a soccer server, which provides a commontest-bench to various multi-agent systems. Wepresent an exper- iment on cooperative action learning amongsoccer- player agents on the server. Oursoccer agent can learn whetherhe should shoot a ball or pass it. Introduction Soccer (association football) is a typical team game, in which each player is required to play cooperatively. Figure 1: Soccer players and a ball And soccer is a real-time game in which situation changes dynamically. We have chosen soccer as one of standard problems for the study on multi-agent sys- ¯ Team play is advantageous. tems, and we are now developing a soccer server for ¯ As precise communication by language is not ex- the research. We present an experiment on coopera- pected, effectiveness must be provided by combining tive action learning amongsoccer-player agents on the simple signals with the situation. server. These characteristics show that soccer is an appro- Soccer as a Standard Problem priate example for evaluation of multi-agent systems. -
Nassau Sports Product Catalog
2019 www.nassau.co.kr NASSAU SPORTS E - mail : [email protected] Tel : +82-70-4493-4577 Fax : +82-32-326-2570 PRODUCT CATALOG Address : Nassau B/D, 42, Bogwang-ro 106beon-gil, Deogyang-gu,Goyang-si, Gyeonggi-do, Republic of Korea Since our foundation in 1971 as a company specializing in sporting goods, we have been endeavoring hard to keep our technology state-of-the-art and provide our custom- ers the best service they can get in the industry. In an effort to do so, we could manage to get appointed as an official match ball supplier for several international tournaments: 86 Asian Games for tennis, soccer, handball and volleyball, 88 Olympics Games for tennis and 4 Grand Slam tournaments for tennis. In addition, we got our balls interna- tionally approved by world-renowned sports federations such as International Tennis Federation(ITF), Fédération Internationale de Volleyball(FIVB), International Handball Federation(IHF), Fédération Internationale de Football Association(FIFA) and Korea Football Association(KFA). 028 Volleyball Section 1 04 History Section 5 029 PATRIOT 3000 / NEW PATRIOT(VNP) 030 AERO DYNAMIC(VAD) / POWER DYNAMIC(VPD) / ATTACK(VA) Section 2 06 Soccer Ball / Futsal Ball / Handball / Rugby Ball 08 TUJI FA “New Technology of 4 Panel” 010 TUJI FA (SSTG-5FF) 011 TUJI PREMIUM(SSTG-P) / TUJI PREMIUM(SSTP) / TUJI(SSTG-5) Section 6 032 Tennis Racket / Badminton Racket / Shuttlecock / Padminton 012 NEW TUJI(SSHTJ) / TUJI(SSNTJ) / TUJI 88(SBT88) 034 SENIOR TOUR / SENIOR TEAM / OPTIMUM PRO 013 TUJI TRAPPER(SBTR) / CHAMPIONSHIP -
Return to Competition: Individual Sport Considerations
Pennsylvania Interscholastic Athletic Association Return to Competition: Individual Sport Considerations Pennsylvania Interscholastic Athletic Association National Federation of State High School Associations Pennsylvania Department of Education Pennsylvania Department of Health Sports Medicine Advisory Committee TABLE OF CONTENTS General Considerations for All Sports ..................................................................................................................... 2 General Considerations for Officials ....................................................................................................................... 7 General Considerations for Fall Sports: Cross Country ........................................................................................................................................... 11 Field Hockey ............................................................................................................................................. 12 Football .................................................................................................................................................... 14 Golf ........................................................................................................................................................... 17 Soccer ....................................................................................................................................................... 18 Tennis ...................................................................................................................................................... -
Stick Making Guide
How To Make a Broomball Stick: An Introductory Guide Created by: Justin Hicks Ben Hoover Michael W. Johnson Tyler Schwartz Introduction Broomball has become a tradition for many Michigan Tech students during the long winter months in Houghton, Michigan. The following guide provides step‐by‐ step instructions on how to make a broomball stick for IRHC Broomball at Michi‐ gan Technological University. It is best suited for individuals who have never con‐ structed a broomball stick before. It can also be used as an instructional resource for those teaching others how a broomball stick is constructed. The guide will lay out the general procedure for constructing a broomball stick. The guide will also discuss different styles of broomball sticks that can be made and the IRHC rules and regulations that pertain to the construction of broomball sticks. Remember that this guide is intended only for those individual who going to be competing in IRHC Broomball at Michigan Tech. Broom Diagram (Yes, this is a diagram of a broom!) This diagram points out some im‐ portant parts of the broom, but more importantly, gives them a standard name that will be used throughout the rest of the guide. Broom Handle Metal Coil Metal Ring Broom Head Strings Bristles IRHC Rules and Regulations Page 6 of the IRHC Broomball Rules and Details packet states the following: ‐ Only the broom’s original handle may be attached to the original broom head (i.e. no homemade brooms). ‐ Brooms must have a wooden handle. ‐ No official Broomball brooms will be allowed (hard plastic brooms). ‐ A minimum of six (6) inches of bristle must extend below the broom’s handle. -
Towel Flip Standing Long Jump
Foot Bottle Flip Trap Shoe Flip Spoon Your Flip Relay Lid Soccer Towel Flip Water Bottle Scooter Pillow Bowl Ball Bullseye Race Trap Stack The Backboard Sneakers Bank It Stacks & Jacks Fan Favorite Shoe Balance Standing Pillowcase Sock-er Long Jump Penguin Race Sack Race Keep it Up Skee-Ball Shoe Flip Back Click Here for Video Demonstration Equipment- 1 Sneaker, Open Space, timer/stopwatch Set Up- Make sure you have plenty of open space around you. 1 Point Directions: ● How many points can you score in a minute. 2 Points ● Put your sneaker on just over your toes. ● When timer starts, flick your shoe off your foot. ● 1pt- sneaker lands on side; 2 pts- sneaker lands 3 Points upright; 3 pts- sneaker lands upside down ● 0pts- sneaker hits the ceiling/fan/knocks something over. ● Write your score on Field Day Scorecard. Click Here for Video Stack the Sneakers Back Demonstration Equipment- 10-15 pairs of sneakers of sneakers/shoes, item to create home base (plate, cone, cup) Set Up- Make a pile of shoes/sneakers in the middle of players. Place home bases equal distance from shoe pile. Directions: ● Object is to stack the sneakers/shoes on top of one another to create a tall stack of shoes. ● When signal begins, go to stack and take 1 shoe/sneaker and place it on your home base. ● Repeat taking 1 shoe/sneaker at a time until all sneakers/shoes are gone from the middle pile ● It is okay if your stack falls. Fix the stack before you go and get another shoe. -
A Type System for Format Strings E
ifact t * r * Comple t te A A n * te W E is s * e C n l l o D C A o * * c T u e m S s E u e S e n I R t v A Type System for Format Strings e o d t y * s E a * a l d u e a t Konstantin Weitz Gene Kim Siwakorn Srisakaokul Michael D. Ernst University of Washington, USA {weitzkon,genelkim,ping128,mernst}@cs.uw.edu ABSTRACT // Untested code (Hadoop) Most programming languages support format strings, but their use Resource r = ... format("Insufficient memory %d", r); is error-prone. Using the wrong format string syntax, or passing the wrong number or type of arguments, leads to unintelligible text // Unchecked input (FindBugs) output, program crashes, or security vulnerabilities. String urlRewriteFormat = read(); This paper presents a type system that guarantees that calls to format(urlRewriteFormat, url); format string APIs will never fail. In Java, this means that the API will not throw exceptions. In C, this means that the API will not // User unaware log is a format routine (Daikon) log("Exception " + e); return negative values, corrupt memory, etc. We instantiated this type system for Java’s Formatter API, and // Invalid syntax for Formatter API (ping-gcal) evaluated it on 6 large and well-maintained open-source projects. format("Unable to reach {0}", server); Format string bugs are common in practice (our type system found Listing 1: Real-world code examples of common programmer 104 bugs), and the annotation burden on the user of our type system mistakes that lead to format routine call failures. -
40Plus Games
NAME TOSS Throw the tennis ball around the circle. As you throw it, announce your name VERY loudly and HELLO keep going until everyone has had a chance to make their bold introduction. Now change it up – instead of announcing your name to the “royal ball” say the name of the person to whom you are throwing the ball. Change positions in the circle and try again. INTRODUCTION CIRCLES You may be nervous when meeting someone for the first time. Pretend the ball is large emerald jewel from the Royal Treasury. Group members number off as a “1” or “2” or by “toilet paper folders” and “toilet paper crumplers.” Each group chooses a leader, and then choose which group will get the jewel first. That group’s leader then presents the jewel to someone in the “un-jeweled” group, who must dazzle the giver with 45 seconds of valuable personal information. Leaders should feel free to give some topics for conversation. After the time is up, jewel recipients then present the jewel to someone in the other group for new introductions. Repeat until all have spoken. MAGIC TRANSFORMING TENNIS BALL Every medieval kingdom has a good old wizard hanging around. Merlin (the leader) begins with the tennis ball and tosses it to another “magician-in-training” in the group. As it is tossed, Merlin casts a hand in a spell-enchanting fashion while shouting out the name of a new object. The ball is now “transformed” into that object. Each time, the conversion “spell” must create an object just a little bit bigger than its current size. -
Tennis Rules and Etiquette Guidelines Our Spectator Policy, This Will Not Be Tolerated
Tennis Rules and Etiquette Guidelines our spectator policy, this will not be tolerated. If someone does question you on a line call or a ruling Tennis you have the right to remove them/ask them to leave the playing area. Should they refuse to leave the playing area, let them and the player know that the cheat sheet player will now receive a code violation related to this action and will continue to do so until either one of two things occur – Rules and a) The parent/spectator leaves the area b) The player reaches his or her 3rd code violation and is defaulted from match play. Etiquette Parent/Spectator Continues to be Unruly: These are grounds for immediate removal from the playing area and facility. Should they refuse to leave the premises and having gone through Code Violations, then do Guidelines not hesitate to contact security or the police to have them removed. Safety of the players, officials, tournament staff and facility staff always comes first. Should an Incident Occur: If something does take place, please contact USTA Northern: http://www.northern.usta.com. Tennis Rules and Etiquette Guidelines Tennis Rules and Etiquette Guidelines Etiquette (for parent or spectators) 1. Any attempt by a spectator (which includes the above mentioned) to question an official, tournament staff or 1. Use primarily your “inside voice” when watching player regarding a line call or other ruling during match matches. play will be cause for immediate removal from the playing area and, if warranted, from the premises. 2. Don’t cheer, shout encouragement, or applaud during a point or serve. -
Backboard Bank It
BACKBOARD BANK IT Get Ready: 5 Large Sock Balls, Laundry Basket or Bucket, A Wall Get Set: Roll up the socks to make sock-balls. Place the basket or bucket against the wall. Mark a distance 5’ – 10’ From the basket. GO! ● This event is called Backboard Bank It. ● The obJect oF this game is to score as many points as you can in 1 minute. ● Do that by tossing the sock balls oFF oF the wall and into the basket. You MUST use the wall as your backboard and bank it into the basket. ● Score a point For every sock that is banked into the basket. ● Write your score down on the oFFicial Field Day Score Card. BOWL BALL Get Ready: 6 Bowls, 1 Sock Ball, Paper & Pencil to Tally Score Get Set: Set the bowls on the floor in a triangle pattern 3-4 inches apart. Put a piece of paper with the point total in the bottom of each bowl. Mark a throwing line 6-8 ft. away. Hint: Big bowls are easier than small bowls! GO! • The object of the game is to see how many points you can score in 1-minute. • You do this by tossing the sock ball into the bowls and scoring points based upon where they land. • After each throw, retrieve the sock ball and hustle back and throw again. • If the sock lands in a bowl, use the pencil and paper to tally the points for that bowl. • After 1-minute, calculate your tally and write your total number of points on the official Field Day Score Card.