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Considering the series effects of high power microwave such as thermal fast electrons effect, collision frequency effect and ionization frequency effect, a unified high power microwave (HPM) propagation model is presented in this paper. A unified air-breakdown model for single-pulse HPM is discussed in detail and the breakdown threshold is determined. It is found that the frequency of plasma induced by high power microwave is greater than previous value. The threshold of air breakdown increases with altitude increasing under the same condition. When the threshold reaches a minimum, a reverse trend will appear. And the minimum value will be obtained in an area of 30-60 km. The typical phenomenon waveform and threshold are gained in the experiment of air breakdown in microwave darkroom. And a well uniform distribution of the air breakdown threshold is shown theoretically and experimentally.

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In this study, 262 Chinese-speaking English learners have been randomly sampled as subjects by stratified sampling in terms of their natural groups (i.e., schools, majors or grades) to demonstrate their transformation of dative wh-question into relative clause construction. Based on the acquisition data collected, the conclusive implication is predictably analogous to that of dative wh-question alternation. To elaborate, the marked PS occurs before its unmarked counterpart PPP, which is obviously incompatible with the markedness hypothesis, however, conforming to the syntactically termed economy principle adopted generally to account for an otherwise unexplained phenomenon from a markedness perspective. As far as the structure of the items is concerned, learners tend to take No-prep. strategy (omitting the preposition at all) corresponding to the stimulus sentences categorized under certain type. Thus, the acquisitional sequence in real time is: PS < No-Prep. < PPP. Chi-square test suggests that the difference between the acquisitional sequence and English proficiency level of subjects is significant, so is the difference between the acquisitional sequence and the structure of the stimulus sentences. Furthermore, PPP shares a higher percentage in relative clauses than that in wh-questions, which is accounted for as the influence of topic-command structure, a usual sentence type in Chinese defined as the topic-prominent language. Besides, the markedness status of who and whom also exerts its influence on the acquisitional sequence, which provides the prerequisite for the construction of the processing acquiring mechanism hypothesis. It is suggested in conclusion that items may as well be inputted in the form of routines, rather patterns.