衡量FONST3000系统传输质量好坏的质量有下列哪些指标()。 A.OSNR B.

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问题:

衡量FONST3000系统传输质量好坏的质量有下列哪些指标()。

A.OSNR

B.边模抑制比

C.消光比

D.功率大小

考点:移动通信机务员鉴定烽火设备部分烽火设备部分题库
题型:单项选择题

某施工单位承建一居民楼,现浇混凝土框架结构,自拌C30混凝土,内隔墙采用加气混凝土砌块双坡屋面,防水材料为3mm厚SBS防水卷材,外墙为玻璃幕墙。生产技术科编制了安全专项施工方案和环境保护方案。一层混凝土浇捣时,项目部对现场自拌混凝土容易出现强度等级不够的质量通病,制定了有效的防治措施。一层楼板混凝土浇筑完毕后,质检人员发现木工班组不按规定拆模。

该工程屋面的卷材防水的基层应作为圆弧的有()。

A.烟囱

B.檐口

C.前坡面

D.屋脊

E.后坡面

题型:单项选择题

下列排斥反应,哪个是由于受者体内存在针对供者特异性抗原的预存抗体引起的()。

A.超急性排斥反应

B.加速性排斥反应

C.急性排斥反应

D.慢性排斥反应

E.以上都不是

题型:单项选择题

人体缺碘会影响正常的生命活动.为提高人体素质,食盐加碘、食物补碘已引起人们的重视.据报道,人从食物中摄取碘后碘便在甲状腺中积存下来,通过一系列化学反应可形成甲状腺素.甲状腺素的结构如图:

(1)我国目前使用______加工碘;

(2)甲状腺素的分子式为______;

(3)青少年及成人缺碘可引起______.

题型:单项选择题

A公司是一个商业企业。由于目前的收账政策过于严厉,不利于扩大销售,且收账费用较高,该公司正在研究修改现行的收账政策。现有甲和乙两个放宽收账政策的备选方案,有关数据如下:

项 目现行收账政策甲方案乙方案
年销售额(万元/年)240026002700
收账费用(万元/年)402010
所有账户的平均收账期2个月3个月4个月
所有账户的坏账损失率2%2.5% 3%
  已知A公司的销售毛利率为20%,应收账款投资要求的最低报酬率为15%。坏账损失率是指预计年度坏账损失和销售额的百分比。假没不考虑所得税的影响。
  要求:通过计算分析,回答应否改变现行的收账政策如果要改变,应选择甲方案还是乙方案

题型:单项选择题

阅读理解。

     My bookshelves are full of dust-and with good reason. When it comes to cleaning that part of my

home, I suffer from the most serious case of avoidance (回避反应症).

     The thing is this: when I do set out to clean and re-organize my books, which seldom happens, I

place myself into a really bad situation. No sooner do I take a title from the shelf, blow off the dust, and

wipe down the cover than I find myself sitting on the floor with legs crossed and my back against the

wall. Pretty soon books get piled up on my legs as I am reunited with old friends.

     It is as if these books have voices, and each wants to say its piece. "Remember me? I was given to

you when you went into the Navy, so that you would never lack for companionship," one whispers.

Another says, "I was your first book of poems, given to you before you learned to love poetry." And

a third, "I was the book that made history so attractive to you."

     Perhaps the greatest pleasure of re-organizing my books are the surprises - or better said,

reunions-that occur. During my latest book-cleaning adventure, I found one that had fallen behind the

shelf: "Tales of Edgar Allan Poe." Not an unusual title, but the words written on the first page made it

very special: "With Love from Mom and Dad, Christmas 1965." What's this? A book on the physics

of lasers().It is filled with mathematical statements, and I had bought it at a library sale when I was 12,

not long after the laser had been invented. I couldn't understand a bit of it, but I did learn what "laser"

meant.

     What I end up with when I empty my bookshelves is a cross-section (横剖面) of my personal

history. It's like a road cut where one sees all the layers of rock going back through time to the beginning

of the simplest life forms. The books I've read-and kept-are not just old friends. They are my résumé ?

1.What could be said about the author?

A. He is too busy to tidy up his bookshelves.  

B. He considers his books treasured possessions.

C. He has made a lot of notes in his books.    

D. He is a lover of science books.

2. By saying that his books have voices, the author means            .

A. hey bring back happy memories  

B. they are recorded in human voice

C. they say a lot about human history  

D. they offer good topics for discussion

3.What does the author enjoy most from re-organizing his books?

A. Finding some missing books.          

B. Putting books in good order.

C. Learning something new from the books.

D. Rediscovering interesting stories behind some books.

4. The underlined word "résumé" in the last paragraph probably means __________.

A. personal history  

B. precious notes

C. good companion

D. imply life forms  

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