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
a straight face
acissors
anellus
armored chain-scraper conveyor
Atenism
auditory percussion
badge out
ball burst testing
bamies
boojee
breakaway emergency
building-materials
business insolvency
cavalry fight
caved
Chilumba R.
cimanes del tejar
class Gnetopsida
clearance underneath the gear case
dichotomous branching
direct-cycle cooling system
dumbness
earth(ed) circuit
eddy friction
elai
electron tube rack
emissive material
engrauliss
enquote
epididymiss
exsertum
extra-spectral color
field-independence
flec spec
Flos Imperatae
gaseous train
gasification degree
general psychology
generator routine
glass specimen
gone dark
graphitic pressed pipe
guarded experimental subassembly
Hans Adolf Krebs
heart-stirring
hemichromis bimaculatus
hetjens-museum
hi-low
high-pressure separator
hinge belt
holographs
in the desk
indiscriminate use of pesticide
ineludible
information communication
interphase-intraphase diffusion
intradural lipoma
Kentucky black bass
Kliplev
line coupling transmission system
liquid metal fuel reactor
loop back Windsor chair
mahiz
moot hall
night movement
percutaneous transluminal balloon mitral valvuloplasty
periodic component
phrynolysin
pionless
play game
precision matrix
preemptive scheduling
push theory
pusia cancellarioides
Raucourt-et-Flaba
refolded fold
retia venosa vertebrarum
road pizza
rotational delay
Saint Isaac's Cathedral
sea-squirts
segment attribute field
selfhardening steel
serial-parallel addressing
shining clubmosses
sodium nitrate
spiral forming
standard change gear
streptococcus anhemolyticuss
strike-forces
stubble
SWCNT
therry
tragicomical
trewin
under car antenna
vacuum-tubes
variable visibility
vicorps
worldcare
zonifulgal
zyma