Select boards allowing optical protection from the following options. （）A、OPB、OPCSC、OPMSD、SWEE、OPMF、OMCP
Select boards allowing optical protection from the following options. （）
- A、OP
- B、OPCS
- C、OPMS
- D、SWE
- E、OPM
- F、OMCP
相关考题：
无源光网络由哪些部分构成?() A.OLT（Optical Line Terminal）－光线路终端B.ONU（Optical NetworkUnit）－光网络单元C.ONT（Optical Network Terminal）－光网络终端D.ODN（Optical Distribution Network）－光分配网
●假设供应商S和供应情况SPJ的关系模式分别为S(Sno，Sname，Status，City)和SPJ(Sno，Pno，Jno，Qty)。SQL语句 (19) 不能正确地查询出"零件号Pno等于'P3'的供应商名Sname"，而 (20) 能正确查询的关系代数表达式。(19) A．SELECT DISTINCT SnameFROMSWHERE EXISTS(SELECT*FROM SPJWHERE S.Sno=SPJ.SnOAND SPJ.Pno=′P3′B．SELECT DISTmCT SnameFROMSWHERE 0(SEIECT COUNT(*)FROM SPJWHERE S.Sno=SPJ.SnoAND SPJ.Pno=′P3′)C．SELECT SnameFROMSWHERE EXISTS(SELECT*FROM SPJWHERE S.Sno=SPJ.SnoAND SPJ.Pno=′P3′)D．SELECT SnameFROMS，SPJWHERES.Sno=SPJ.SnoAND SPJ.Pno=′P3′)GROUP BYSname(20) A．Πsname(S)Dσ 0 Pno=′P3′(SPJ)B．Πsname(SD∞σ Pno=′P3′(SPJ))C．Πsname(S)-Πsname(σ Pno≠′P3′(Sσσ(SPJ)D．Πsname(S)-Πsname((S∞σ Pno≠′P3′(SPJ)
查询订购单号首字符是“P”的订单信息，应该使用命令A．SELECT * FROM 订单 WHERE HEAD（订购单号，1）=“P”B．SELECT * FROM 订单 WHERE LEFT（订购单号,1）= “P”C．SELECT * FROM 订单 WHERE “P”$订购单号D．SELECT * FROM 订单 WHERE RIGHT（订购单号,1）= “P”
Which two capabilities are granted with the SUPER privilege?() A.Allowing a client to kill other client connectionsB.Allowing a client to shut down the serverC.Allowing change of the server runtime configurationD.Allowing client accounts to take over the account of another user
查询订购单号首字符是”P”的订单信息，应该使用命令A)SELECT*FROM订单WHERE HEAD（订购单号，1）=”P”B)SELECT*FROM订单WHERE LEFT（订购单号，1）=”P”C)SELECT*FROM订单WHERE “P” $ 订购单号D)SELECT*FROM订单WHERE RIGHT(订购单号,I)=”P”
假设供应商S和供应情况SPJ的关系模式分别为：S(Sno, Sname, Status, City)和SPJ(Sno, Pno, Jno, Qty)。SQL语句______不能正确地查询出“零件号Pno等于'P3'的供应商名Sname”。A．SELECT DISTINCT Sname FROM S WHERE EXISTS (SELECT* FROM SPJ WHERE S.Sno=SPJ.Sno AND SPJ.Pno='P3')B．SELECT DISTINCT Sname FROM S WHERERE 0＜ (SELECT COUNT (*) FROM SPJ WHERE S.Sno=SPJ.Sno AND SPJ.Pno='P3')C．SELECT Sname FROM S WHERE EXISTS (SELECT* FROM SPJ WHERE S.Sno=SPJ.Sno AND SPJ.Pno='P3')D．SELECT Sname FROM S, SPJ WHERE S.Sno=SPJ.Sno AND SPJ.Pno='P3') GROUP BY Sname
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（ ）is not the advantage of GERT(graphical evaluation and review techniques) as compared with PERT(project evaluation and review techniques)A.allowing loopingB.allowing for dummy tasksC.allowing branchingD.allowing multiple project end results
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c．c．若需得到在所有仓库中都存在的产品的名称，则对应的查询语句为： SELECT name FROM P WHERE(28)(SELECT*FROM W WHERE NOT EXISTS(SELECT*FROM I WHERE P.productID=I.productID AND W.warehouseID=I.warehouseID))(28)A．EXISTSB．NOTEXISTSC．IND．NOTm
假设供应商S和供应情况SPJ的关系模式分别为S(Sno，Sname，Status，City)和SPJ(Sno，Pno，Jno，Qty)。SQL语句(25)不能正确地查询出“零件号Pno等于'P3'的供应商名Sname"，而(26)能正确查询的关系代数表达式。A．SELECT DISTINCT Sname FROM S WHERERE 0 ＜(SELECT COUNT( *)FROM SPJ WHERE S. Sno = SPJ. Sno AND SPJ. Pno = 'P3')B．SELECT DISTINCT Sname FROM S WHERE EXISTS(SELECT * FROM SPJ WHERE S. Sno=SPJ. Sno AND SPJ. Pno= 'P3')C．SELECT Sname FROM S WHERE EXISTS( SELECT * FROM SPJ WHERE S. Sno = SPJ. Sno AND SPJ. Pno = 'P3')D．SELECT Sname FROM S, SPJ WHERE S. Sno = SPJ. Sno AND SPJ. Pno = 'P3' GROUP BY Sname
What three in combination are factors that can cause four－wave mixing in fiber－optic cables? ()(Choose three.) A. low optical powerB. high optical powerC. few optical channelsD. many optical channelsE. low chromatic dispersionF. high chromatic dispersionG. too much power differential in the optical channels
The （） will have a rotating honorary chairman.A、Board of DirectorsB、Boards of DirectorC、boards of directorD、Board Directors
In the OSNR model for EDFA amplifiers, SNR OUT = 1/(1/SNR IN + FhvB/P IN ), what does SNR IN represent?（）A、the signal to noise of the current optical amplifierB、the signal to noise of the previous amplifier or sourceC、the signal to noise introduced by the optical multiplexerD、the accumulated noise to signal ratio of the optical channel
What three in combination are factors that can cause four-wave mixing in fiber-optic cables? （）(Choose three.)A、low optical powerB、high optical powerC、few optical channelsD、many optical channelsE、low chromatic dispersionF、high chromatic dispersionG、too much power differential in the optical channels
OWM的英文全称是（）A、Optical Wavelength MultiplexB、Optical wavelength MonitorC、Optical wavelength MemoryD、All are right
查询订购单号首字符是P的订单信息，应该使用命令（）。A、SELECT＊FROM订单WHERE HEAD（订购单号，1）＝”到B、SELECT＊FROM订单WHERE LEFT（订购单号，1）=nPnC、SELECT＊FROM订单WHERE””＄订购单号D、SELECT＊FROM订单WHERE RIGHT(订购单号，1)_"P'-
无源光网络由哪些部分构成？（）A、OLT（Optical Line Terminal）－光线路终端B、ONU（Optical NetworkUnit）－光网络单元C、ONT（Optical Network Terminal）－光网络终端D、ODN（Optical Distribution Network）－光分配网
（ ）is not the advantage of GERT （Graphical evaluation and review techniques）as compared with PERT （project evaluation and review techniques）. A、Allowing loopingB、Allowing for dummy tasksC、Allowing branchingD、Allowing multiple project end results
Which two capabilities are granted with the SUPER privilege?（）A、Allowing a client to kill other client connectionsB、Allowing a client to shut down the serverC、Allowing change of the server runtime configurationD、Allowing client accounts to take over the account of another user
单选题In the OSNR model for EDFA amplifiers， SNR OUT = 1/（1/SNR IN + FhvB/P IN ）， what does SNR IN represent？（）A the signal to noise of the current optical amplifierB the signal to noise of the previous amplifier or sourceC the signal to noise introduced by the optical multiplexerD the accumulated noise to signal ratio of the optical channel
多选题What three in combination are factors that can cause four-wave mixing in fiber-optic cables？（）Alow optical poweBhigh optical powerCfew optical channelsDmany optical channelsElow chromatic dispersionFhigh chromatic dispersionGtoo much power differential in the optical channels
单选题In the OSNR model for EDFA amplifiers, SNR OUT = 1/(1/SNR IN + FhvB/P IN ), what does SNR IN represent?（）Athe signal to noise of the current optical amplifierBthe signal to noise of the previous amplifier or sourceCthe signal to noise introduced by the optical multiplexerDthe accumulated noise to signal ratio of the optical channel
多选题What three in combination are factors that can cause four-wave mixing in fiber-optic cables? （）(Choose three.)Alow optical powerBhigh optical powerCfew optical channelsDmany optical channelsElow chromatic dispersionFhigh chromatic dispersionGtoo much power differential in the optical channels