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Objective: To validate and normalize the Nomophobia Questionnaire (NMP-Q) for use in Iran. Method: This study was a correlation study. Participants in this study were 280 undergraduate students of Mashhad universities in 95-96 who were selected by multistage cluster sampling and responded into Persian version of Nomophobia Questionnaire (NMP-Q) and the Cell-Phone Over-Use Scale (COS). Forty participants answered the questionnaire again two weeks later to assess the validity of the test-retest. The data were analyzed by SPSS statistical software version 20 and LISREL version 8 software. Cronbachchr('39')s alpha, Pearsonchr('39')s correlation analysis and confirmatory factor analysis were used in this study. Results: The results indicated high validity of the questionnaire (Cronbachchr('39')s alpha for all items was 0.921 and for subscales ranging from 0.748 to 0.885). Concurrent validity was equal to (r = 0.51) and retest validity equal to (r = 0.81). Also confirmatory factor analysis results showed that all four factors of the original questionnaire were confirmed in Persian version. Conclusion: According to the results, the Persian version of the Nomophobia Questionnaire has good validity and validity for use in Iran.

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This paper presents a direct slip angle control (DSAC) for rotor side power converter of standalone doubly-fed induction generator (DFIG) DC systems. The conventional direct torque control (DTC) for the rotor side converter (RSC) of the standalone DFIG-DC system is also introduced to evaluate the proposed DSAC compared to the conventional DTC method. In this regard, the proposed DSAC method is mathematically analyzed. Then, three states including output DC voltage change, wind speed change, and load change are simulated and performed for both the proposed DSAC and conventional DTC methods. Various simulations and experiments substantiate that the electromagnetic torque ripple, current harmonics, and the output DC voltage dip, caused by the sudden load-change, are reduced in the proposed DSAC method compared to the conventional DTC method. Besides, the parameter dependency is reduced in the proposed DSAC method since the stator voltage and current sensors are removed.