growing demands and requires of high data rate systems cause significant increase of high frequency systems for wideband communication applications. as mixers are one of the main blocks of each receivers and its performance has great impact on receiver’s performance; in this thesis, a new solution for ku-band (12-18 ghz) mixer design in tsmc 0.18 µm is presented. this mixer has high linearity a...

thermal barrier coatings (tbcs) are used to provide thermal insulation to the hot section components of gas turbines in order to enhance the operating temperature and turbine efficiency. hot corrosion and thermal shocks are the main destructive factors in tbcs which comes as a result of oxygen and molten salt diffusion into the coating. in this thesis atmospheric plasma spraying was used to dep...

1- in a search directed to the reaction of compound)23(the cycloaddition reaction of 1,3- diphenylisobenzofurane)14(with p-benzoquinone)19(,followed by addition of cyclopentadiene was carried out.the specific spacial stracture of its ir,nmr,mass spectra. 2- in another attempt the kinetic stability and behavior of compounds)20(and)23(was studied.the main subject of this study was the highly reve...

the methods which are used to analyze microstrip antennas, are divited into three categories: empirical methods, semi-empirical methods and full-wave analysis. empirical and semi-empirical methods are generally based on some fundamental simplifying assumptions about quality of surface current distribution and substrate thickness. thses simplificatioms cause low accuracy in field evaluation. ful...

dendrimer synthesis strategies now provide virtual control of macromolecular nanostructures as a function of size and surface/interior functionality. these strategies involve the covalent assembly of hierarchical components reactive monomers , branch cells or dendron’s around atomic or molecular cores according to divergent/convergent dendrite branching principles.combinon of two or more dendri...

today, scouring is one of the important topics in the river and coastal engineering so that the most destruction in the bridges is occurred due to this phenomenon. whereas the bridges are assumed as the most important connecting structures in the communications roads in the country and their importance is doubled while floodwater, thus exact design and maintenance thereof is very crucial. f...

the study aims to achieve research and testing of hypotheses survey techniques and questionnaires to collect information used. 61 questions in the questionnaire included 15 questions and 46 open questions according to research in the study population, girls and their mothers as the value of different children investment should be. mothers according to the research community benefits from havi...

this study was an attempt to investigate and compare the effect of lexical inferencing and concept mapping on developing vocabulary retention of iranian language learners. sixty homogeneous students from different intact classes who were being taught as intermediate learners in sokhan english institute participated in this study. they were in different classes. a teacher made test as a pre-test...

from its emergence till present time marxist principles has undergone great changes since their promulgation by marx. many theorists and thinkers set at rectifying marxist tenets and introducing those of their own while others advocated its main concepts and attempted at improving them. among marxist philosophers who had an intensive study of marxs ideology, is louis althusser whose reflections...

چکیده تمام نما مقدمه: این تحقیق برای بررسی میزان خلاقیت و عناصر آن (انعطاف- سیالی- ابتکار و بسط) در کارشناسان فوق برنامه های تربیت بدنی دانشگاههای تهران صورت گرفته است. بطور کلی خلاقیت به معنای توانایی تولید اندیشه ها و ایده های جدید و ترکیب آنها با یکدیگر و بیشتر در جنبه های فکری نظری و به اصطلاح فعالیتهای ذهنی و طراحی قبل از عمل به کار می رود و دارای چهار عنصر به شرح زیر می باشد. 1- سیالی...