噪声系数是用来衡量放大器本身的噪声水平,其公式是什么?

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问题:

噪声系数是用来衡量放大器本身的噪声水平,其公式是什么?

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双肺叩诊过清音是

A.支气管炎
B.支气管哮喘
C.肺炎
D.肺结核
E.肺气肿

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In the 19th century, there used to be a model of how to be a good person. There are all these torrents of passion flowing through you. Your job, as captain of your soul, is to erect dams to keep these passions in check. Your job is to just say no to laziness, lust, greed, drug use and the other sins.

  These days that model is out of fashion. You usually can’t change your behavior by simply resolving to do something. Knowing what to do is not the same as being able to do it. Your willpower is not like a dam that can block the torrent of self-indulgence. It's more like a muscle, which tires easily. Moreover, you're a social being. If everybody around you is overeating, you’ll probably do so, too.

  The 19th-century character model was based on an understanding of free will. Today, we know that free will is bounded. People can change their lives, but ordering change is not simple because many things, even within ourselves, are beyond our direct control.

  Much of our behavior, for example, is guided by unconscious habits. Researchers at Duke University calculated that more than 40 percent of the actions we take are governed by habit, not actual decisions. Researchers have also come to understand the structure of habits—cue, routine, reward.

  You can change your own personal habits. If you leave running shorts on the floor at night, that'll be a cue to go running in the morning. Don’t try to ignore your afternoon snack craving. Every time you feel the cue for a snack, insert another routine. Take a walk.

  Their research thus implies a different character model, which is supposed to manipulate the neuralnetworks inside.

  To be an effective person, under this model, you are supposed to coolly examine your own unconscious habits, and the habits of those under your care. You are supposed to devise strategies to alter the cues and routines. Every relationship becomes slightly manipulative, including your relationship with yourself. You're trying to arouse certain responses by implanting certain cues.

  This is a bit disturbing, because the important habitual neural networks are not formed by mere routine, nor can they be reversed by clever cues. They are burned in by emotion and strengthened by strong yearnings, like the yearnings for admiration and righteousness.

  If you think you can change your life in a clever way, the way an advertiser can get you to buy an air freshener, you’re probably wrong. As the Victorians understood, if you want to change your life, don’t just look for a clever cue. Commit to some larger global belief.

小题1:Which of the following is the first-to-none element in the 19th-century character model?

A.Action.

B.Capacity.

C.Resolution.

D.Enthusiasm.小题2:The 19th-century model supposedly does not work on the grounds that ________

A.one’s wished should be pondered before acting.

B.the comparison of free will to a dam is groundless.

C.it has been proved impractical and cannot hold true.

D.there were many other factors beyond one's control.小题3:The research at Duke University indicated that ________

A.One’s behavior is tough to change.

B.Habit has an unidentified structure.

C.Habit plays a vital role in one's behavior.

D.Both habit and will power are of significance.小题4:According to the new character model, personal behavior could be altered through

A.techniques to break old routines.

B.techniques to provide different physical cues.

C.cues to change all the former unconscious habits.

D.cues to manipulate the habitual neural responses.小题5:We can learn from the passage that the new character model ________

A.can generate changes in one's life like what advertisers do.

B.highlights the neural and psychological aspects of habit change.

C.has been identified a new method of changing behavior perfectly.

D.has an advantage over others in dealing with emotional aspects of behavior.

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若电源线有一相内部断线,则必须引起电动机的()运行。

A、尺压

B、失压

C、短路

D、过载

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柑桔树脂病因其发病部位不同而有多种名称,它们是()。

A.树脂病

B.砂皮病

C.蒂腐病

D.疮痂病

E.溃疡病

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山坡地分全阳坡、半阳坡及背阳坡,半阳坡是指()

A.南、北 

B.东、西 

C.西北、东北 

D.西南、东南

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