Swimmers can drown in busy swimming pools when lifeguards fail to notice that they are in trouble. The Royal Society for the Pre

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问题     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 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 manufacturer, Poseidon Technologies.
    Poseidon keeps watch through a network of underwater and overhead video cameras. AI software analyses the images to work out swimmers, trajectories. 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 on 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 so the 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" 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 Poseid6n system will be officially opened next week at a pool in High Wycombe, Buckinghamshire. One man who is impressed with the idea is Travor Baylis, 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 on a Poseidon system ought to be investing similar amounts in teaching children to swim.
Which of the following statements about Trevor Baylis is NOT true?

选项 A、He runs.
B、He invented the clockwork radio.
C、He was once an entertainer.
D、He runs a company.

答案A

解析 这道题问的是:下面这些有关Travor Baylis的命题中哪一个不是真的?A他跑步。A中的run是不及物动词。最后一段中的“Baylis runs a company...”中的run是及物动词,作“经营”解。二者不是一回事。可见A是正确答案。B他发明了机械装置的无线电。这个选项可以从下面这个句子中找到(第六段):One man who is impressed with the idea is Travor Baylis, inventor of the clockwork radio.C说的是:他曾经是一名职业娱乐节目表演者。D他经营一家公司。C和D都可以在第六段里找到。
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