单选题X线平均波长与最短波长（λ0）的关系是（）A λmean=0.5λ0B λmean=1.0λ0C λmean=2.0λ0D λmean=2.5λ0E λmean=3.5λ0

第1题

接入信道中,导频信道的开环输出功率为mean pilot channel output power,数据信道的开环输出功率为meandatachanneloutputpower,则接入信导前缀中的导频信道输出功率为()A.mean pilot channel output power-mean data channel output powerB.mean pilot channel output power+mean data channel output powerC.mean pilot channel output power-0.5*mean data channel output powerD.mean pilot channel output power+0.5*mean data channel output power

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第2题

The soundings on the chart are based on the depth of water available at ______.A.mean low waterB.mean lower low waterC.mean high waterD.mean high water springs

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第3题

X线最强波长与最短波长的关系是A.λmax=0.5λ0B.λmax=1.5λ0C.λmax=2.0λ0SXBX线最强波长与最短波长的关系是A.λmax=0.5λ0B.λmax=1.5λ0C.λmax=2.0λ0D.λmax=2.5λ0E.λmax=3.5λ0

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第4题

The average height of the surface of the sea for all stages of the tide over a 19 year period is called ______.A.mean high waterB.mean low waterC.half-tide levelD.mean sea level

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第5题

The reference datum used in determining the heights of land features on most charts is ______.A.mean sea levelB.mean high waterC.mean low waterD.half-tide level

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第6题

X线摄影用线量最强波长的计算公式为A.λmin=1．24／kVp(nm)B.λmin=12．4／kVp(nm)C.λmean=2．5λmin(nm)D.λmax=1．5λmin(nm)E.λmax=2．0λmin(nm)

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第7题

X线平均波长与最短波长(Xo)的关系是A.λmean=0．5λ0B.λmean=1．0λ0C.λmean=2．0λ0D.λmean=2．5λ0E.λmean=3．5λ0

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