در طی سالهای اخیراستفاده ازمنابع انرژی تجدید پذیر در شبکه های مدرن بنا به دلایل زیست محیطی و اقتصادی به طور گسترده استفاده شده است همچون نیروگاههای بادی و خورشیدی .ولتاژتولیدی این نیروگاهها اغلب به فرم dc می باشد وادوات الکترونیک قدرت به عنوان مبدل و پل بین شکل موج dc وac استفاده می شوند.این پروسه باعث ایجاد پالسهایی برروی شکل موج خروجی می شود که می تواند وارد تجهیزات قدرت همچون ترانسفورماتور ی...

in current study, 63 samples of bat populations collected from differ regions were used for evaluating the geographic variations. twenty cranial and dental characters for traditional morphometric and landmarks method on the ventral, dorsal skull and mandible for geometry morphometric studies were used. statistical analyses of traditional morphometric and geometry morphometric data indicated low...

as far as bandura’s (1977) conceptualization of the sense of self-efficacy is concerned, it is argued to be context- and even task-specific, compared to other concepts like self-esteem (brown, 2000); therefore, upon the previous research studies, related theories and definitions, and the ideas and views obtained from the interviews conducted with the scholars, the current research study aimed a...

Introduction: Musculoskeletal Discomforts are one of the main problems in all occupations and industries. Printing industry workers are involved in tasks that increase the risk of musculoskeletal Discomforts. So, the aim of this study was to investigate the relationship between musculoskeletal Discomforts and manual load lifting and workers’ postures in a printing industry. Methods: In this st...

  Background and aims: Work-related musculoskeletal disorders (WMSDs) are the most prevalence problems of working populations in many developing countries and specifically in Iran. One of the most important disorders is Carpal Tunnel Syndrome (CTS) which has been reported in many industries, especially in workers of automotive companies. The aim of this study is the risk assessment of related f...

nowadays enhancing critical thinking in learners is considered one of the foreign language teachers’ tasks due to its high position in foreign language classrooms. when it comes to selecting materials for language classrooms, there are obviously some criteria that teachers should apply. the present study aimed at a critical thinking based analysis of ten picture story books and ten folktales th...

Background: Major depression disorder is one of the most common psychiatric disorders which is associated with impairment in cognitive functions, including working memory. In recent decades, a non-invasive and painless technique, called Repetitive Transcranial Magnetic Stimulation (rTMS) has been used in treatment of treatment-resistant depressions. Current study was conducted to investigate th...

abstract cooperative learning refers to small groups of learners working together as a team to solve a problem, complete a task, or accomplish a common goal. in a cooperative environment one’s success is directly related to the success of other members because the focus on the individual shifts towards the group. to test the effectiveness of the method, using jigsaw technique, a study was cond...

the present study investigated construct equivalence of multiple choice (mc) and constructed response (cr) item types across stem and content equivalent mc and cr items (item type ‘a’), non-stem-equivalent but content equivalent mc and cr items (item type ‘b’), and non-stem and non-content equivalent mc and cr items (item type ‘c’). one hundred seventy english-major undergraduates completed mc ...