时间:2019-02-24 作者:英语课 分类:英语听力文摘 English Digest


英语课

  D: OK, Yael, you want to build an aquatic 1 robot,and you're trying to figure out the most efficient way to move it through water, what do you do?

Y: I am guessing the answer isn't to build a robot using a lot of root-force to move forward?

D: Anyone who has tried walking or running in water knows how much effort that can take compared to swimming, which by the way is a hint.

Y: It is?

D: Look at the fish, my friend. Many fish after all, live in turbulent waters.

Y: I see where this is going. Over time, fish have made adaptations to conserve 2 energy when swimming against the current.

D: And researchers at Harvard figured out the underlying 3 physics.

Y: So they literally 4 understand what it means to swim like a fish?

D: Yes. You see, when water hits objects like branches, rocks, or other fish, it forms strings 5 of little whirlpools, or vortices. So researchers set up a tank with water flowing in one direction, and dropped a cylinder 6 in it that generated vortices.

Y: So what did they find out?

D: The researchers observed that rather than fighting the current, the fish simply slalomed between vortices, using a swimming style that resembles a flag flapping in the wind. The advantage of all the side-to-side movement is that it requires very little muscle activity. In fact, fish can use this technique to hold their position and rest while in rough patches of water.

Y: I bet that comes in handy for swiming up a fish letter.

D: These findings have applications ranging from technology to conservation.

Y: And it gives us a whole new dimension of what it means to swim like a fish.



adj.水生的,水栖的
  • Aquatic sports include swimming and rowing.水上运动包括游泳和划船。
  • We visited an aquatic city in Italy.我们在意大利访问过一个水上城市。
vt.保存,保护,节约,节省,守恒,不灭
  • He writes on both sides of the sheet to conserve paper.他在纸张的两面都写字以节省用纸。
  • Conserve your energy,you'll need it!保存你的精力,你会用得着的!
adj.在下面的,含蓄的,潜在的
  • The underlying theme of the novel is very serious.小说隐含的主题是十分严肃的。
  • This word has its underlying meaning.这个单词有它潜在的含义。
adv.照字面意义,逐字地;确实
  • He translated the passage literally.他逐字逐句地翻译这段文字。
  • Sometimes she would not sit down till she was literally faint.有时候,她不走到真正要昏厥了,决不肯坐下来。
n.弦
  • He sat on the bed,idly plucking the strings of his guitar.他坐在床上,随意地拨着吉他的弦。
  • She swept her fingers over the strings of the harp.她用手指划过竖琴的琴弦。
n.圆筒,柱(面),汽缸
  • What's the volume of this cylinder?这个圆筒的体积有多少?
  • The cylinder is getting too much gas and not enough air.汽缸里汽油太多而空气不足。
学英语单词
acados
accelerating by gravity
acceleration amplitude
addisin
Admr.
age-class vector
allii macrostemonis bulbus
Allium teretifolium
analog approach
artificial rain
BG (bearing)
binocular tube
blood disorders
brave the worst
brickfilmed
buck the system
calcium metazirconate
chihsia age
component color switcher
concrete pouring machine
conductive foil
court of university
daily time report
delirant
dicyclic flower
dock leaf
double shell form
drawing lift
ebelmenite
Edvard Munch
end stone
fazls
fensive
fibrillar element
freezing-point lowering
fully-mechanized coal winning face unit
gas permeation
George, David Lloyd
Gosseck
graphite-water reactor
hexachloromelamine
HTML, html
in marriage
INTSUM
leaf burn
leucocarpum
lindsaea cultrata
loose key
maimuna
managerial competency
Marchihue
mccarran-walter
Mörön Gol
nasal polypus snare
nonconflicted
nonscheduled maintenance
nontelescoping
Nospan
operationalists
overhead cableway
Phoeniculus
plough-boy
plug-in type
polydioxanone
printer box
product market expansion grid
prosoposchisis
pullyblank
rail line
riffle
right-abouts
rocky mountains cherries
satellite digital and analog display
seededness
sets-in-use rating
single lacing
slab cake
smeralda
spellken
spongiaria
stabilized pinch
subaerial-laminated crust
suborder Xenarthra
subrotoes
supraposition
table height control
termas
texturing effect
thiotolene
timefield
tracer solution
unbar
undefined file designator
underground river
urinary stasis
water cooled internal combustion engine
water wave motion
weather vane
wedge beam
woollen fabric
Z-crank