问题 问答题 简答题

在开始继电器KJ的自闭电路中接有XJJ61-62接点的作用是什么?

答案

参考答案:

可防止调车信号错误开放。在调车车列完全进入进路内方,信号关闭后,若值班员误按该信号按钮,则将使FKJ按重复开放信号的励磁电路吸起而后自闭。则KJ将又一次接通了经由FKJ前接点接通的自闭电路,并在第一个区段解锁,SJ吸起后,KJ仍不落下。于是,就在机车车辆出清最末一个区段后,在ZJ缓放过程中,又使XJJ吸起,使信号错误重复开放。有了XJJ第六组前接点在调车车列进入进路时,XJJ落下,不使KJ错误励磁,从而防止调车信号错误开放。

问答题

In my children’s lifetimes, I believe gorillas, chimpanzees and orangutans will all become extinct in the wild. So the question we have to ask ourselves is this: do we want our children to see only in zoos what used to exist in the real world (46) It is the great apes that will disappear first, because there are so few of them left, and because they’re so vulnerable to changes in their habitats.

Many of the threats to these animals result from a global economy not local pressures. The threat to the orangutan in Indonesia, for example, is largely a result of deforestation and the risks to primates in Africa result from the timber-trade and the demand for bush-meat. (47) The two work together: logging opens up the forest, which means that the bush-meat can be got out fast, to Kinshasa or to London.

(48) If we want to avoid the disaster scenario, people in developed countries will have to take a global perspective and accept responsibility for the damage export crops such as timber, coffee, cut flowers or even green beans, do to the environment. The challenge is to avoid simply imposing western attitudes on local peoples.

Already there are no truly wild places left in the world. (49) Looking at wildlife has become the preserve of the middle classes over the last twenty-odd years, and as wild animals become even rarer, so more tourists want to see them. But tour ism alone plainly cannot conserve the world’s animals; economic development is the priority.

For the future, I suspect that ff you really want to do something about wild life conservation, you would be better off putting your money into women’s education rather than just into the protection of flagship species. (50) Women often bear the direct costs of wildlife conflict; their knowledge of how to deal with conflict and how to control their own reproductive destinies may yet determine the survival of many threatened species.

Looking at wildlife has become the preserve of the middle classes over the last twenty-odd years, and as wild animals become even rarer, so more tourists want to see them

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