时间:2019-01-14 作者:英语课 分类:VOA标准英语2015年(十一月)


英语课

Scientists Analyze Modern Tennis Technique of Sliding 科学家分析现代网球技术中的滑动


Sliding to return a shot is a common tennis practice on clay courts, but lately players have started using it on grass and hard courts as well. Scientists say it is faster than running and allows athletes to change direction more quickly.


“The speed of the game has increased a lot because the players are serving faster than years before," said Daniel Ura, a researcher in the University of Sheffield's Department of Mechanical Engineering. "It could be because of the materials of the rackets, or could be the strings as well. But I think it's a necessity of the players to reach the ball faster.”


So far, only a few top players have mastered the technique off clay. For effective slides, the shoes must perfectly match the court’s surface, and this is where the science comes in handy.


“I think it will become more like a Formula 1 race probably," Ura said, with the right shoe depending on the weather or the surface conditions.


Looking for the best match between shoe and surface, researchers at the University of Sheffield have built a special mechanical rig that can measure the shoe traction. 


“In order to do that," said Matt Carre, an instructor in the mechanical engineering department, "we need to understand a number of parameters, including how the shoe changes, how the properties of the shoe affect that interaction, how the properties of the tennis courts affect that, and also other factors like temperature" and how the players slide or move around the court.


The research, in partnership with the International Tennis Federation, may lead to different materials for tennis shoes, different court surfaces, and ultimately faster and even more exciting tennis matches.



学英语单词
A-service area
aerospace craft
augure
base loading
bases on balls
be in league to do
beehler
Bellarmino
cat-ear
catastrophic-illness
chape
cheveron notch
click-bait
closeness of relation
cold junciton
commonizes
complete limit
Conium maculatum poisoning
constantly acting load
continuous production process
critical bearing point
cyclic load-elution test
david gruns
deoxidized steel
developmental norm
differential capstan
dihaploid
dry construction
economics of consumption
edit test
edulious
elephant's ear
emptily
encrustment
entreprenetwork
epizoic
equation of state (EOS)
esophagical
family lactobacteriaceaes
fen-lich
fiber spinning
fit the action to the word
frauen
Galidzga
Ghon complex
goitrogenicity
Hanzi ink jet printer
hard-to-please
honey mouse
hoovers
humane studies
is in agreement with
k-spar (k-feldspar)
know something for a fact
Kogaku
landtied island
Letha Ra.
macromorphology
mammifer
method of spot parameter measurement
microbrachia
multipactor breakdown
nansen ridge
naren
newtons disk
non critical item
nondeterministic nested stack automaton
normal form of vector fields
nsn
osmotic effect
parastasia ferrieri formosana
pearlweeds
phylum cycliophoras
plane of uniform expansion or contraction
poltroon
power points
propyl p-hydroxybenzoate
Putnam.
Quiniluban Is.
ransack one's brain wits
repeat offender
rock soap
skeleton sledding
snapping turtle
spit venom
squooshing
Stephen's spots
stone releaser
sulpho-salt
takt time
theobromide
Thermomonosporaceae
throneroom
Tiroungoulou
tit for tat
utmost vacuum seal
verified copy
wire gauze with asbestos
with regard to
wriggle off the hook
yacoscope
yggdrasils