试题与答案

为防止发电机电感参数周期性变化引起的发电机自励磁谐振过电压,一般可采取下列哪些措施?

题型:多项选择题

题目:

为防止发电机电感参数周期性变化引起的发电机自励磁谐振过电压,一般可采取下列哪些措施?()

A.发电机容量小于被投入空载线路的充电功率

B.避免发电机以全压向空载线路合闸

C.快速励磁调节器限制发电机异步自励过电压

D.速动过电压继电保护切机,限制发电机异步自励过电压的作用时间

答案:

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题型:单项选择题

A few years ago I had an "aha!" moment regarding handwriting.

I had in my hand a sheet of paper with handwritten instructions on it for some sort of editorial task. It occurred at first that I did not recognize the handwriting, and then I realized whose it must be. I finally became aware of the fact that I had been working with this colleague for at least a year, maybe two, and yet I did not recognize her handwriting at that point.

It was a very important event in the computerization of life—a sign that the informal. Friendly communication of people working together in an office had changed from notes in pen to instant messages and emails. There was a time when our workdays were filled with little letters, and we recognized one another’s handwriting the way we knew voices or faces.

As a child visiting my father’s office, I was pleased to recognize, in little notes on the desks of his staff, the same handwriting I would see at home in the notes he would leave on the fridge—except that those notes were signed "dad" instead of "RFW".

All this has been on my mind because of the talk about The Rise and Fall of Handwriting, a book by Florey. Sire shows in her book a deep concern about the fall of handwriting and the failure of schools to teach children to write well, but many others argue that people in a digital age can’t be expected to learn to hold a pen.

I don’t buy it. I don’t want to see anyone cut off from the expressive, personal associations that a pen still promotes better than a digital keyboard does. For many a biographer, part of really getting to know their subjects is learning to read their handwriting.

What some people advocate is teaching one of the many attractive handwritings based on the handwriting of 16th century Italy. That may sound impossibly grand—as if they want kids to learn to draw by copying classical paintings. However, they have worked in many school systems.

According to the author, handwritten notes ().

A.are harder to teach in schools

B.attract more attention

C.are used only between friends

D.carry more message

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题型:单项选择题

Although "naming rights" have proliferated in American higher education for the past several decades, the phenomenon has recently expanded to extraordinary lengths. Anything to get an extra dollar out of donors is fair game. I know colleges and universities sorely need to raise funds in these times of fiscal constraints, but things have gotten a bit out of hand.
Universities and colleges have long been named after donors-think of Harvard, Yale, Brown, and many others. John Harvard would hardly get a bench named after him today, given the modesty of his gift of books for the library back in the seventeenth century. Now it takes much more to get one’s name on a college. One institution, Rowan University of New Jersey, changed its name (from Glassboro State College) not long ago when a large donation was made. Buildings, too, have been affected. Traditionally, they were named after people such as distinguished scholars or visionary academic leaders; now they’re often named after big donors.
Why is all of this happening now The main motivation for the naming frenzy is, of course, to raise money. Donors love to see their names, or the names of their parents or other relatives, on buildings, schools, institutions, professorships, and the like. Increasingly, corporations and other businesses also seek to benefit from having their names on educational facilities. Today, no limits seem to exist on what can be named. If something does not have a name, it is up for grabs—a staircase, a pond, or a parking garage. Once all the major facilities have titles, lesser things go on the naming auction block. Colleges and universities, public and private, are all under increased pressure to raise money, and naming brings in cash.
It is unproductive. Separate branding weakens the focus and mission of an institution and perhaps even its broader reputation. It confuses the public, including potential students, and feeds the idea that the twenty-first-century university is simply a confederation of independent entrepreneurial domains.
The trends we see now in the United States, and perhaps tomorrow in other countries, will inevitably weaken the concept of the university as an institution that is devoted to the search for truth and the transmission of knowledge. All this naming distracts from the mission of an institution that has almost a millennium of history and cheapens its image. It is a sad symbol indeed of the commercialization and entrepreneurialism of the contemporary university.

The main purpose for corporations to donate money to universities is ______.

A.to raise more money

B.to get benefit and reputation

C.to train skillful students for them

D.to improve educational facilities

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