2022年考博英语-外交学院考前拔高综合测试题(含答案带详解)第73期

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1、2022年考博英语-外交学院考前拔高综合测试题(含答案带详解)1. 单选题With so much focus on the Ohio energy firm whose lapses may have triggered the blackout of 2003, its been hard to remember that the real question is not how it started, but why it spread so far and so fast. Rather than tackle that question head-on, most commentat

2、ors have reached for the usual metaphors: it was a chain reaction, a cascading failures domino effect. All of these are borrowed from the physical sciences. Maybe a better way to look at it is in biological terms.We already use the language of epidemiology when we speak of “viruses” propagating acro

3、ss the Internet, “infecting” our computer. Likewise, its tempting to view the blackout, spreading from link to link along the power grid, as a pernicious kind of electrical contagion. But thats not quite the right metaphor, either. The blackout was not caused by an infectious electrical disease; it

4、was caused by the grids immune response to the threat of such a disease. In other words, the grid suffered a violent allergic reaction, a sort of anaphylactic shock.Just as the symptoms of a severe allergic reaction are caused not by the offending bee who stings itself but by the overzealous respons

5、e of the bodys immune system to it, so the blackout was aggravated by the grids attempt to defend itself, one power station at a time. Threatened by a torrent of electrical energy gone berserker overwhelmed by the sudden loads placed on it, each power plant in turn tripped its circuit breakers, deta

6、ching itself from the grid. Though this strategy achieved its desired aim-saving each plants generator from being damagedit was too myopic to serve the best interests of the grid as a whole.What is needed is a more subtle, coordinated mode of response. When our own immune systems are performing at t

7、heir best, they orchestrate their defenses through countless chemical conversations among T-cells and antibodies, enabling these defenders to calibrate their response to pathogens. In the same way, the thousands of power plants substations in the grid need to be able to communicate with one another

8、when any part of the system is breached, so they can collectively decide which circuit breakers should be tripped and which can safely remain intact.The technology necessary to achieve this has existed for about a decade. It relies on computer, sensors and protective devices tied together by optical

9、 fiber so that all parts of the grid would be able to talk to one another at the speed of light-fast enough to get ahead of an onrushing blackout and confine it.The sensors would continuously monitor the voltage, frequency and other important characteristics of the electricity coursing through the t

10、ransmission lines. When a line appeared at risk of being overloaded, a computer would decide whether to switch on a protective device. At present, such decisions are made purely parochially. Power plants defend themselves first, and dont worry about the consequences for neighboring plants on the gri

11、d. Nor do they consider any potentially helpful or harmful actions that those neighbors might be taking at the same time.In the new approach, each plant would have nearly instantaneous information about all the other plants and power lines in its extended neighborhood. Everyone would know what every

12、one else was doing and thinking. As threats arose (either from random failures or malicious attacks), the sensors would fire a flurry of warning signals down the optical fibers, and the networked computers would decide which protective devices to activate to contain the threat most effectively. The

13、grid would then be responding as an integrated entity, not as a ragtag collection of selfish units. It would look a lot like an organism defending itself.Granted, such a distributed control system would cost billions of dollars and, in this era of deregulation, there would be little incentive for en

14、ergy companies to join forces and build it, especially when the big money is in power generation. But the construction of a system wide immune network would be well worth the cost. Without it, our overburdened grid is likely to fail more and more often, and might even collapse, with costs that would

15、 be incalculable, both economically and in terms of national security. State and federal governments need to step in and provide incentives for utilities to do the right thing.Of course, even if this new kind of smart defense system were to be built someday, one can already imagine an insidious diso

16、rder that might eventually outsmart it and afflict it, a catastrophic disruption of the immune system itself, rather than the grid its supposed to protect. Such a thing would be the technological analog of AIDS.A grim prospect, perhaps, but a realistic one. We need to stop pretending that the grid is ever going to be a perfectible machine. Just as bacteria eventually develop resistance to the antibiotics used to kill them, the defense of the grid will require ev

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