نتایج جستجو برای: rf because of low signal

تعداد نتایج: 21269979  

1995
R. Tighe P. Corredoura

A model of the RF feedback system for PEP-II has been developed to provide time-domain simulation and frequency-domain analysis of the complete system. The model includes the longitudinal beam dynamics, cavity fundamental resonance, feedback loops, and the nonlinear klystron operating near saturation. Transients from an ion clearing gap and a reference phase modulation from the longitudinal fee...

2009
Anis LATIRI

The fast development of wireless communication systems requires more flexible and cost effective radio architectures. A long term goal is the software defined radio, where communication standards are chosen by reconfiguration of hardware. Direct analog to digital conversion of the radio frequency (RF) signal is still unrealistic at present time, due to the high requirements imposed on the analo...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه لرستان - دانشکده ادبیات و زبانهای خارجی 1393

rested on sociocultural theory (sct), this study attempted to examine the effect of written corrective feedback (wcf) followed by producing written languaging on developing writing accuracy over new tasks. to this aim, two intact iranian efl classes at the low-intermediate level were randomly assigned to two experimental groups: direct (n = 25) and indirect (n = 25). both groups wrote on a numb...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تربیت مدرس - دانشکده علوم انسانی 1389

rivers and runoff have always been of interest to human beings. in order to make use of the proper water resources, human societies, industrial and agricultural centers, etc. have usually been established near rivers. as the time goes on, these societies developed, and therefore water resources were extracted more and more. consequently, conditions of water quality of the rivers experienced rap...

2000
DAVID RUNTON

With the increasing importance of spectral efficiency in mobile communications, linearity of the RF PA has become a critical design issue for non-constant-envelope digital modulation schemes.1 This issue is particularly significant in spread spectrum applications such as CDMA and wideband CDMA (W-CDMA) base stations, where the peak-to-average ratio of modulated RF signals can vary over a range ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه صنعتی خواجه نصیرالدین طوسی - دانشکده مهندسی برق و کامپیوتر 1391

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...

2009
N. Gudino M. J. Riffe L. Bauer J. A. Heilman M. A. Griswold

Material and Methods: The amplifier diagram is shown in Fig. 1. A digital encoded RF pulse is amplified and split into two out-of-phase digital signals through a high speed Emitter Coupled Logic (ECL) comparator. This is demodulated through a band-pass filter and further amplified through a cascade of high-speed differential amplifiers. Two stages of Voltage-Mode Class-D (VMCD) amplifiers boost...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه یزد 1390

the debate whether esp teachers need to have knowledge of the specialized field they are teaching has been an issue in the literature over the last two decades. the aim of conducting this study was to explore iranian learners’ and instructors’ beliefs and attitudes concerning the role of specialized knowledge in teaching esp classes. a seventeen item questionnaire was administered to 400 esp le...

it is not possible to understand developments of a country’s culture and civilization without knowing his believes and myths. whether it is north or south, east or west, planes or mountains, sahara or deserts, here in iran every corner includes valuable and precious treasures which are known all over the world, and cultural – historical objects which are found here adorn all well known museums of the globe. zagros mountains, lorestan province locating at the heart of that, are not only the same, but are more prominent than other iranian regions. you can not find someone who does not know what the lorestani bronzes are, and there is no museum that not be pride of having a piece of that. the said bronzes which are manufactured four millenniums b.c. are admired nearly by all those researchers because of their beauty, diversity and technique. lorestani artistic works including stone engraves, bronzes and clays, show an ideal and metaphysical world beside real world which explain mental system of human beings on that era against sensations and phenomena happening around them. men main mental occupation on that time was he unknown world which had surrounded them, and they used to use the religion to fight life’s natural factors, and art was a tool of religious and mythical painting which was far from reality and had entered into the abstract domain. as natural objects have become subjects of lorestani art, it cleanses them from any non – intrinsic limitations and external factors which surround them and darken their meanings, and just shows their main specifications. artist in the said civilization is not searching for realism. although these are few works showing the nature, but in effect there is no wish to imitate touchable factors of the nature, and artist has turned real phenomena to encoded signs as per his own mentality. this procedure is called stylization.

پایان نامه :دانشگاه آزاد اسلامی - دانشگاه آزاد اسلامی واحد تهران مرکزی - دانشکده هنر و معماری 1391

it is not possible to understand developments of a country’s culture and civilization without knowing his believes and myths. whether it is north or south, east or west, planes or mountains, sahara or deserts, here in iran every corner includes valuable and precious treasures which are known all over the world, and cultural – historical objects which are found here adorn all well known museums...

2008
C. Harrison M. E. Merritt A. D. Sherry C. Malloy

Introduction Hyperpolarized (HP) [1-C]pyruvate has been shown to be metabolized to [C]bicarbonate and other products both in vivo and in isolated perfused hearts. The appearance of a [C]bicarbonate signal following an injection of hyperpolarized [1-C]pyruvate reflects the activity of pyruvate dehydrogenase (PDH) in heart. In some metabolic circumstances, the [C]bicarbonate signal is low and con...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید