【单选题】后来人们将木柱竖于交通要道,作为识别道路的标志是( )
【简答题】If the impact factor of a journal in 2017 is 1.5 and there are 2000 articles published on this journal from 2015 to 2016, these articles have been cited for totally (number)times in 2017.
【单选题】高压单台三相电容器的电容元件组在外壳内部一般接成( )。
【判断题】The influence of an author’s journal articles can be evaluated by the impact factor(IF).
【单选题】当要传播的信号频率在30兆赫兹以上时,必须使用()方式