● Although a given waveform. may contain frequencies over a very broad range, as a practical matter any transmission system will be able to accommodate only a limited band of (71) . This, in turn, limits the data rate that can be carried on the transmission (72) . Asquare wave has an infinite number of frequency components and hence an infinite (73) . However, the peak amplitude of the kth frequency component, kf, is only 1/k, so most of the (74) in this waveform. is in the first few frequency components. In general, any digital waveform. will have (75) bandwidth. If we attempt to transmit this waveform. as a signal over any medium, the transmission system will limit the bandwidth that can be transmitted.
(71)A. frequencies B. connections C. diagrams D. resources
(72)A. procedure B. function C. route D. medium
(73)A. source B. bandwidth C. energy D. cost
(74)A. frequency B. energy C. amplitude D. phase
(75)A. small B. limited C. infinite D. finite
(71)
A. frequencies
B. connections
C. diagrams
D. resources
(72)
A. procedure
B. function
C. route
D. medium
(73)
A. source
B. bandwidth
C. energy
D. cost
(74)
A. frequency
B. energy
C. amplitude
D. phase
(75)
A. small
B. limited
C. infinite
D. finite
第1题:
包容类Contain和内嵌类Embed定义如下: #include <iostream.h> class Contain { private: int x; protected: int z; public: class Embed { private: int y; public: Embed(){y=100;} int Embed_Fun(); }MyEmbed; int Contain_Fun(); }; 对上面的定义,正确的描述是( )。
A.定义类Embed对象的语句是:Contain::Embed embed;
B.类Contain的成员函数Contain_Fun()中可以用MyEmbed.y的方式访问类Embed的私有成员y
C.类Embed的成员函数Embed_Fun()中可以直接访问类Contain和的私有成员x
D.类Embed的成员函数Embed_Fun()中可以直接访问类Contain的保护成员z
第2题:
类 Contain 的定义如下: class Contain { private: int x; protected: int z; public: class Embed { private: int y; public: Embed ( ) { y=100; } int Embed_Fun(); }MyEmbed; int Contain_Fun(); }; 下列对上面定义的描述中,正确的是( )。
A.定义类Embed对象的语句是:Contain::Embed Myobject;
B.类Contain的成员函数Contain_Fun()中可以访问对象MyEmbed的私有成员y
C.类Embed的成员函数Embed_Fun()中可以直接访问类Contain的所有成员
D.类Embed的成员函数Embed_Fun()中只能直接访问类Contain的公有成员
第3题:
第4题:
包容类Contain和内嵌类Embed定义如下: #include<iostream.h> class Contain { private: int X; protected: int z; public: class Embed { private: int y; public: Embed(){y=100;} int Embed_Fun(); }MyEmbed; int Contain_Fun(
A.定义类Embed对象的语句是:Contain? Embed embed;
B.类Contain的成员函数Contain_Fun()中可以用MyEmbe D.y的方式访问类Embed的私有成员y
C.类Embed的成员函数Embed_Fun()中可以直接访问Contain的私有成员x
D.类Embed的成员函数Embed_Fun()中可以直接访问Contain的保护成员Z
第5题:
A.contain,inoculate,quarantine,andtreat
B.inoculate,contain,quarantine,andtreat
C.quarantine,contain,inoculate,andtreat
D.preparation,identification,traceback,andpostmortem
E.preparation,classification,reaction,andtreat
F.identification,inoculation,postmortem,andreaction
第6题:
下面英文日期写法错误的是____?
A.May 1, 2015
B.1 May,2015
C.1 May 2015
D.May 1st, 2015