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 ...

the present study aimed at exploring cognitions of iranian english teachers within the context of english for academic purposes (eap). to this end, the cognitions of two groups of eap teachers with respect to their pedagogical content knowledge (pck) and their sense of professional identity (pi) were probed. two language teachers and two content instructors who had at least five years of eap te...

abstract the third millennium has started, but the world is facing with serious challenges in achieving international security and peace. various human rights violations have lead the states to find means to protect human rights. also article 55 of the united nations charter introduces the respect to human rights and fundamental freedom as the most suitable ways to realize peace and security. ...

introduction acetic acid bacteria are large group of obligate aerobic gram negative bacteria with the ability to oxidize ethanol to acetic acid (1). they are widely distributed in natural habitats and classified in family acetobacteraceae. members of this family are useful in industrial production of vinegar(2). acetic acid bacteria (aab) can use substrates as glucose, ethanol, lactate or glyc...

the present study has tried to accomplish an analysis of margaret atwood’s novels oryx and crake, and the year of the flood in the light of posthuman and cyborg theories. considering posthumanism as a critical reading of some notions of humanism focus of which in this thesis has been identity, new definitions for humanity and human identity are formed. haraway’s cyborg, as one possible new figu...

this is an original study on the effect of a polyisobutylene – polydimethylsiloxane (pibpdms) block copolymer modifier used as an interfacial active agent on the dynamics behaviour of single newtonian drops suspended in a polyisobutylene (pib) newtonian matrix. the results were divided in two sections. the first part included the experiments carried out on the non-modified and 2% block cop...

هدف تحقیق حاضر بررسی تاثیر نشانه های فرا گفتمان متنی بر فهم متون انگلیسی به وسیله ی زبان اموزان فارسی زبان است.این تحقیق علاوه بر این کوشیده است تا میزان اگاهی این زبان اموزان و نحوه ی تعامل انان را با متون خوانده شده در زبان انگلیسی به وسیله ی پرسش نامه ی تهیه شده بررسی کند.بر اساس محتوای یک متن انگلیسی یازده سوال درست /غلط طرح گردید و یک مرتبه با ان متن و یک مرتبه با نسخه ای که نشانه ها...

seismic retrofit strategies have been developed in the past few decades following the introduction of new seismic provisions and the availability of advanced materials and methods. it can be observed that new approaches to deal with more lateral forces are more innovative and more energy absorbent. in line with this, there is a growing trend toward the use of steel shear walls as a system with ...

insurers have in the past few decades faced longevity risks - the risk that annuitants survive more than expected - and therefore need a new approach to manage this new risk. in this dissertation we survey methods that hedge longevity risks. these methods use securitization to manage risk, so using modern financial and insurance pricing models, especially wang transform and actuarial concepts, ...

this study attempted to explore if teaching english collocations through two different modes of awareness-raising and input flooding has any possible differential effect on immediate retention as well as retention in a delayed assessment. it also compared the possible differential effect of teaching english collocations implicitly and explicitly on actively using the items in writing. m...