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A Power Conditioning System (PCS) for a PV power generation system obtains the maximum power from a photovoltaic (PV) array by Maximum Power Point Tracking (MPPT), but losses in the inverter are a factor in lowering the power obtained by the MPPT. The generation of harmonic currents is also a problem for PCS. This paper proposes the application of the Peak Current Control Switching (PCCS) method in PCS for PV Generation System using a half bridge inverter. The half bridge inverter improves efficiency by reducing the number of switching elements and further suppresses harmonic currents by controlling them using the PCCS method. In this paper, a comparative simulation of the conventional Hysteresis Current Control (HCC) method and the proposed PCCS method is performed using a half bridge inverter. The results of harmonic analysis and comparative simulation of total harmonic distortion (THD) show that the PCCS method generates harmonic components near the switching frequency, and that the proposed PCCS method always has a lower distortion rate than the conventional HCC method.

This study analyzes the extent to which dictation performance and linguistic features (linguistic difficulty of sentences during dictation) can predict general proficiency in English as a second language (ESL) learners. To this end, this study constructed a multiple linear and a non-linear regression models that predict general ESL proficiency (in which independent variables were the dictation performance scores and the linguistic features of sentences) and verified the correlation between the predicted and observed general ESL proficiencies. The results showed that general ESL proficiency could be predicted by dictation performance and linguistic features. Furthermore, the results indicated significant effects on dictation accuracy, sentence length, and mean word length.

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