. فیلتر پیشنهادی دارای فرکانس قطع db 3- در 2.38 ghz و باند‎گذر این فیلتر، از باند عبور به باند قطع که معمولاً از فرکانس قطع db 3- تا فرکانسی که در آن میزان تضعیف به db 20- می‎رسد برابر با ghz 0.45است. باند قطع این فیلتر با میزان تضعیف db 21- از ghz 2.5 تا23.5ghz است. insertion loss در باند عبور کمتر از db 0.1 و return loss در باند عبور بهتر از db 16. 9- و در باند قطع نزدیک به 0 db می‎باشد که نشا...

  Background and Objectives: Studies have indicated that sleep is essential for the development and survival of the brain and increases the brain's capacity for cognitive functions, and sleep loss disrupts cognitive performance. The present review study aimed to investigate the effects of sleep deprivation on learning and memory with an emphasis on the role of sex hormones. Materials and...

the present dissertation aims to investigate four-word lexical bundles in applied linguistics research articles by iranian and internationally-published writers. the aims of this study are two-fold: first of all, attempts have been made to create a comprehensive list of the most commonly used four-word lexical bundles categorized by their type and token frequency, their structural characteristi...