题目内容
If not for the English examination I would have gone to the concert last Sunday,
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Why do people's eyes read by little "jumps"？
A Pool Watch
Swimmers can drown in busy swimming pools when lifeguards fail to notice that they are in trouble．The Royal Society for the Prevention of Accidents says that on average 15 people are drown in British pools each year, but many more suffer major injury after getting into difficulties．Now a French company has developed an artificial intelligence system called Poseidon that sounds the alarm when it sees someone in danger of drowning．
When a swimmer sinks towards the bottom of the pool, the new system ．sends an alarm signal to a poolside monitoring station and a lifeguard's pager．In trials at a pool in Ancenis, near Nantes, it saved a life within just a few months, says Alistair McQuade, a spokesman for its maker, Poseidon Technologies．
Poseidon keeps watch through a network of underwater and overhead video cameras．AI software analyses the images to work out swimmers' trajectories(轨迹)．To do this reliably, it has to tell the difference between a swimmer and the shadow of someone being cast onto the bottom or side of the pool．"The underwater environment is a very dynamic one with many shadows and reflections dancing around," says McQuade．
The software does this by "projecting" a shape in its field of view onto an image of the far wall of the pool．It does the same with an image from another camera viewing the shape from a different angle．If the two projections are in the same position, the shape is identified as a shadow and is ignored．But if they are different, the shape is a swimmer and sothe system follows its trajectory．
To pick out potential drowning victims, anyone in the water who starts to descend slowly is added to the software's "pre-alert" (预警) list, says McQuade．Swimmers who then stay immobile on the pool bottom for 5 seconds or more are considered in danger of drowning．Poseidon double-checks that the image really is of a swimmer, not a shadow,by seeing whether it obscures the pool's floor texture when viewed from overhead．If so,it alerts the lifeguard, showing the swimmer' s location on a poolside screen．
The first full-scale Poseidon system will be officially opened next week at a pool in High Wycombe, Buckinghamshire．One man who is impressed with the idea is Travor Bavlis, inventor of the clockwork radio．Baylis runs a company that installs swimming pools and he was once an underwater escapologist with a circus．"I say full marks to them if this works and can save lives," he says．But he adds that any local authority spending 30,000-plus pounds on a Poseidon system ought to be investing similar amounts in teaching children to swim．
第 36 题 AI means the same as____．
In paragraph 4, which word has similar meaning to the phrase "take a catnap"？
Pesticides (杀虫剂)
Where do pesticides(杀虫剂)fit into the picture of environmental disease？ We have seen that they now pollute soil, water, and food, that they have the power to make our streams fishless and our gardens and woodlands silent and birdless．Man, however much he may like to pretend the contrary, is part of nature．Can he escape a pollution that is now so thoroughly distributed throughout our world？
We know that even single exposures(暴露)to these chemicals, if the amount is large enough, can cause extremely severe poisoning．But this is not the major problem．The sudden illness or death of farmers, farm workers, and others exposed to sufficient quantities of pesticides are very sad and should not occur．For the population as a whole, we must be more concerned with the delayed effects of absorbing small amounts of the pesticides that invisibly pollute our world.
Responsible public health officials have pointed out that the biological effects of chemicals are cumulative(积累的)over long periods of time, and that the danger to the individual may depend on the sum of the exposures received throughout his lifetime．For these very reasons the danger is easily ignored．It is human nature to shake off(摆脱)what may seem to us a threat of future disaster．"Men are naturally most impressed by diseases which have obvious signs," says a wise physician, Dr．Rene Dubos, "yet some of their worst enemies slowly approach them unnoticed．"
第 31 题 Which of the following is closest in meaning to the sentence "Man, is part of nature．"(Line 3～4, Para．1)？
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