t .ahmadzadeh

Evaluation is an integral part of educational programs and undoubtedly, for conducting appropriate evaluation Students should be evaluated in simulated conditions of the future workplace. The purpose of the present study was to design, implement and evaluate an objective structured practical test to assess the practical capabilities of environmental health engineering students at Yasuj Health Faculty in 2020-2021.

In the present descriptive study, 18 senior students of Environmental Health Engineering of Yasuj School of Health and Nutrition Sciences in 2021 were studied. The study instruments were checklists from eleven different stations, which were prepared based on the training program of the relevant course and Its content validity was examined by a panel of experts. Students' skills were evaluated in each station by the evaluator using a checklist. At the end, students completed the Survey form. After collecting the data, it was entered into SPSS20 software and t-test, Mann-Whitney and correlation tests were used to analyze the data.

The results indicated that the average score of stations was more than 50% (63.54). Students in nine stations had a score above 50%, which indicated that the selected stations could be a suitable criterion for evaluating practical skills and OSFE exam was a suitable alternative to written and oral tests at the end of the semester. The score of two stations was less than 50%. This was due to the virtual nature of universities during the COVID-19 epidemic and it was not possible for the students to perform the necessary skills sufficiently during the study period. Stations with an average score of more than 70% indicate the mastery of students in the skills they have learned in laboratories and health-treatment centers. The level of students' satisfaction with the test was also 77.94%.

According to the level of student satisfaction (77.94), it can be said that this exam is a suitable and student-friendly method for assessment and its use is suitable for different courses. Given the average scores that are above average, it seems necessary to review the evaluation methods in the practical sections.

The main purposes of a transformerless grid-connected photovoltaic (PV) system consist of the reduction of leakage current, extraction of maximum power point (MPP), tracking of MPP (MPPT), controlling the active and reactive powers, and having the unity power factor. To achieve the above-mentioned aims, the following actions have been performed in this paper. First of all, a brief analysis of the transformerless PV system has been done by using the conventional full-bridge (FB) topologies with two bipolar and unipolar PWM techniques. Then, an effective solution has been also introduced to significantly reduce the leakage current in the conventional H5 FB topology. Moreover, a proper control method has been proposed by using the combination of the fractional open-circuit voltage (FOCV) and the model predictive control (MPC) strategies to extract the MPP from PV panels, control the injection of the reactive power to the gird and have the unity power factor. At last, the simulation results performed in PSCAD software will be used to prove the correct performance of the proposed control method in the improved H5 FB topology.