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 ...

this study was designed to investigate the impacts of teachers self-disclosure on students foreign language classroom anxiety, attitude to english language learning and their achievement scores at the end of the term. there were 48 female learners of intermediate level. they were not randomly selected. there were one experimental group with 21 students and one control group with 27 students.the...

abstract reception environment has considerable effects on accepting a translation. as the expectations of a target culture and its values and needs change throughout history, its criteria for accepting a translation or rejecting it will change accordingly (gentzler, 2001). the expectations of iran, as the reception environment in the present study, have changed after the islamic revolution. i...

the skill of reading in english as a foreign language is an important and challenging one which is affected both by linguistic and extra linguistic factors. since vocabularies are part and parcel of every reading comprehension text, knowing enough vocabulary always facilitates this process. however, guessing strategy as one of the most important strategies has consistently ignored by language l...

this thesis is presented 10 ghz voltage controlled ring oscillator for high speed application. the voltage controlled ring oscillator was designed and fabricated in 0.13یm cmos technology. the oscillator is 7-stages ring oscillator with one inverter replaced by nand-gate for shutting down in the ring oscillator during idle mode. tri-state inverter was used to control of 126 bit vector in ri...

the subjects of the study are only the tefl teachers and students at gilan university. to obtain the desired data, a questionnaire which was based on the theories and disecussions gathered, was used as the main data gathering instrument. to determine the degree of relationship between variables, covariance and pearson product moment correlation coefficient were the formulas applied. the data we...

in this thesis, a new optically active poly(amide-imide) (pai) was synthesized by the indirect polycondensation reaction of the l-phenylalanine based diacid chloride and 4,4?-diaminodiphenylether in the presence of triethylamine in n-methyl-2-pyrrolidone. the formation of pai was confirmed by ftir, 1h nmr and elemental analysis. in next step, the surface of titanium dioxide (tio2) nanoparticles...

run-out-table (rot) is located between last finishing stand and down coiler in a hot strip mill. as the hot steel strip passes from rot, water jets impact on it from top and bottom and strip temperature decreases approximately from 800-950 °c to 500-750°c. the temperature history that strip experience while passing through rot affects significantly the metallurgical and mechanical properties, s...

abstract part one: the electrode oxidation potentials of a series of eighteen n-hydroxy compounds in aqueous solution were calculated based on a proper thermodynamic cycle. the dft method at the level of b3lyp-6-31g(d,p) was used to calculate the gas-phase free energy differences ,and the polarizable continuum model (pcm) was applied to describe the solvent and its interaction with n-hydroxy ...

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...