many mobile and off-grid devices include electronics and other electrical consumers like servo drives, which need a quite low supply power. since the price for photovoltaic modules drops continuously, photovoltaic power supply is interesting in more and more applications. in solar powered systems, a battery is needed to store energy for the night and cloudy periods. the power electronics of suc...

in the area of automotive engineering there is a tendency to more electrification of power train. in this work control of an induction machine for the application of electric vehicle is investigated. through the changing operating point of the machine, adapting the rotor magnetization current seems to be useful to increase the machines efficiency. in the literature there are many approaches wh...

a significant problem in multicarrier communication systems is the necessity to reduce the value of papr (peak-to-average power ratio) of transmitting signal. in this thesis we study the effect of the system parameters such as coding and modulation types on papr and ultimate ber in a mc-cdma system. in this study we consider fading channel as well as the nonlinearity of transmitter’s amplifier ...

on this project we try to calculated power of hydrogen on dycarbonil compound in different ways ; the first way is shoster way , for sain power of hydrogen notice the different power between central conforms on it and main conform that’s didn’t have hydrogen joint . or in other way different of energy between open and close form. second way, is average way? this is for way that studied conf...

برای هماهنگی آسان تر رله های جریان زیاد در شبکه های بزرگ و بهم پیوسته لازم است تا رله هایی به عنوان نقاط شروع هماهنگی یا همان نقاط شکست تعیین شود، نقاطی که در آن حلقه های شبکه در دو جهت ساعتگرد و پادساعتگرد باز می شوند. در گذشته روشی مبتنی بر سیستم خبره، عواملی همچون محل منابع و یا سطوح اتصال را درقالب قوانین خبره درنظرگرفته و باتوجه به آن ها به تعیین نقاط شکست پرداخته است. اما تعیین کوچکترین م...

any change in the refractive index of a laser active medium can lead to serious degradation of beam quality, laser beam modes, laser performance and variation in the intensity distribution. alteration in the refractive index of laser active medium is especially notable in high power lasers. it is clear that in the laser beam production, the pumping agent induces a great amount of heat which...

one of the most important number sequences in mathematics is fibonacci sequence. fibonacci sequence except for mathematics is applied to other branches of science such as physics and arts. in fact, between anesthetics and this sequence there exists a wonderful relation. fibonacci sequence has an importance characteristic which is the golden number. in this thesis, the golden number is observed ...

وجود معمای امنیت و پایداری آن کشورها را متوجه منطقه، تهدیدات و بی ثباتی های موجود در آن کرده است. تسلط تهدید، رقابت، اختلاف و خصومت، رقابت های تسلیحاتی و اختلافات سیاسی و ائدولوژیک از موانع عمده ی شکل گیری امنیت پایدار در مناطق است. در این میان چرخه ی قدرت یکی از مهم ترین ویژگی های سیستم جهانی و منطقه ای است که تاثیر مستقیمی بر موضوع مذکور دارد. لازم به ذکر است، که انواع چرخه های قدرت، سبب شکل ...

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