6.適合半雙工通信方式數(shù)據(jù)傳輸時屬HDLC規(guī)約的是

A.異步響應(yīng)模式                                            B.異步平衡模式

C.非正規(guī)響應(yīng)模式                                         D.正規(guī)響應(yīng)模式

7.對于12位的模/數(shù)轉(zhuǎn)換器，模/數(shù)轉(zhuǎn)換后的值D為

A.1024                                                          B.1023

C.2048                                                          D.2047

8.計算機局部網(wǎng)絡(luò)的傳輸距離是

A.0.1~l0km                                                    B.10~50km

C.50~100km                                                  D.100~500km

9.發(fā)生無碼的秒數(shù)與發(fā)信總傳輸?shù)拿霐?shù)之比為

A.誤字率                                                       B.誤秒率

C.平均誤碼率                                                D.誤組率

10.異步通信中數(shù)據(jù)接收端的接收時鐘為16倍數(shù)據(jù)速率，以下選項為干擾信息的寬度，其中能被檢驗出來的是

A.12倍時鐘周期                                            B.10倍時鐘周期

C.4倍時鐘周期                                             D.9倍時鐘周期

11.在數(shù)據(jù)傳輸檢錯中，在接收到的碼序列中檢測出有錯碼時就將該序列丟棄不用的是

A.檢錯重發(fā)法                                                B.循環(huán)檢錯法

C.反饋檢驗法                                                D.前向糾錯法

12.電力系統(tǒng)狀態(tài)估計的量測量主要來自

A.調(diào)度人員                                                   B.值班人員

C.SCADA系統(tǒng)                                              D.主機

13.被稱為用戶與網(wǎng)口之間的接口的是

A.傳送層                                                       B.表示層

C.對話層                                                       D.應(yīng)用層

14.物理層數(shù)據(jù)傳輸規(guī)約中______規(guī)定了數(shù)據(jù)采集方式。

A.機械特性                                                   B.電氣特性

C.功能特性                                                   D.電信號功能

15.OSI七層協(xié)議中，傳輸層傳送數(shù)據(jù)的單位為

A.幀                                                              B.比特

C.分組                                                          D.信息