in the first chapter we study the necessary background of structure of commutators of operators and show what the commutator of two operators on a separable hilbert space looks like. in the second chapter we study basic property of jb and jb-algebras, jc and jc-algebras. the purpose of this chapter is to describe derivations of reversible jc-algebras in term of derivations of b (h) which are we...

abstract nowadays, industries cannot play a crucial role in national and international competitions. the tourism industry is no exception. tourism industry development as the most important economic sector and income generation is one of the key challenges of economic development in the world. therefore, countries were successful that take advantage of the capabilities of tourism sector using ...

چکیده معضل چاقی به عنوان عارضه ای جدی برای زندگی بی تحرک و ماشینی، مورد توجه اغلب مراکز بهداشتی و درمانی دنیا قرار گرفته است. چاقی عامل زمینه ساز و در واقع عامل خطری برای بروز بیماری های قلبی - عروقی است که عموماً با کاهش طول عمر مورد انتظار و افزایش بیماری همراه است. هدف پژوهش حاضر تأثیر 12 هفته تمرینات ویبریشن کل بدن، تمرینات هوازی و تمرینات ترکیبی( هوازی و ویبریشن کل بدن) بر ترکیب بدنی زنان ...

in this thesis, a better reaction conditions for the synthesis of spirobarbiturates catalyzed by task-specific ionic liquid (2-hydroxy-n-(2-hydroxyethyl)-n,n-dimethylethanaminium formate), calcium hypochlorite ca(ocl)2 or n-bromosuccinimide (nbs) in the presence of water at room temperature by ultrasonic technique is provided. the design and synthesis of spirocycles is a challenging task becaus...

over the past decades a number of approaches have been applied for forecasting mortality. in 1992, a new method for long-run forecast of the level and age pattern of mortality was published by lee and carter. this method was welcomed by many authors so it was extended through a wider class of generalized, parametric and nonlinear model. this model represents one of the most influential recent d...

the world wide web becomes very popular recently and plays an influential role in english learning. by burgeoning role of source-based writing as partial fulfillment of tefl courses and vast use of the internet, lack of empirical studies to explore these areas is obvious. this study aimed to explore the effect of the amount of familiarity with the web (internet literacy) on junior english stude...

abstract the balvard metamorphic assemblage (bma) crops out at the northeastern margin of the southeastern part of the sanandaj-sirjan zone (ssz) in contacting to the dehshir-baft ophiolitic mélange. this location prepared a special situation to resolve some of the complicated tectonic problems of this part of iran. petrology, micro-tectonics and satellite image investigation were carried out ...

in this investigation the effect of external field on the electron density of nanostructures of cds, cdse, cdte, gaas and polymeric structure of three, four, five and six units of cds as a kind of nanosolar cells has been studied theoretically. as modeling this system in nanodimension, molecular structures has used. specific properties of molecular structures permit us to consider different sym...

the purpose of the present study was to investigate the effect of task-based instruction of vocabulary on the receptive and oral productive acquisition of english vocabulary and compare the results with those obtained from the traditional method. the method and procedure applied in this study was as follows: after the implementation of opt, a group of sixty female students were chosen. the stu...

the present study aimed at investigating how different news agencies using the concept of legitimation/delegitimation represent the same event differently. to this end, van leeuwens (2008) legitimatory/delegitimatory framework was applied to the data gleaned from the iranian state-run news agency fars news, british state-run news agency bbc, and also american state-run news agency voa. the resu...