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...

teachers beliefs have usually been left unattended in the realm of educational research in iranian context. one of those beliefs which seems to impact teachers performance in the classroom is their sense of self-efficacy, which refers to teachers belief in their ability to enhance student achievement and in bringing about positive learning outcomes. the present study aimed to investigate the pr...

for several years, researchers in familiarity of efl teachers with post-method and its role in second and foreign language learners’ productions have pointed out that the opportunity to plan for a task generally develops language learners’ development (ellis, 2005). it is important to mention that the critical varies in language teaching was shown is the disappearances of the concept of method ...

investigation the archetype of mother can help the reader to understand poes works, especially his fiction, better, if not fully. motivated by internal and external drives to get into the universe in its manifold form poe was impelled to art and, from various modes of art, to symbolism. how much was poe successful to produce works of art has been a matter of dispute among critics. however, ther...

‏‎applications such as high definition viedeo reproduction, portable computers, wireless, and multimedia demand, and ever-increasing need for ligh-frequency high-resolution and low-power analog-to-digital converters. flash, two-step flash, and pipeline convertors are fast but consume large amount of power and require large area. to overcome these problems, successive approximation converter blo...

a one dimensional dynamic model for a riser reactor in a fluidized bed catalytic cracking unit (fccu) for gasoil feed has been developed in two distinct conditions, one for industrial fccu and another for fccu using various frequencies of microwave energy spaced at the height of the riser reactor (fccu-mw). in addition, in order to increase the accuracy of component and bulk diffusion, instanta...

nowadays, technical terminology translation plays an important role in human life. specific groups of people all over the world refer to learn these terminologies in order to be familiar with a subject and improve their knowledge in that domain. on the other hand, saving the technical translation equivalent is a particularly salient challenge for technical translators. the present study was con...

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...

we have devided the thesis in to five chapters. the first recollects facts from purely algebraic theory of jordan algebras and also basic properties of jb and jb* - algebras which are needed in the sequel. in the second chapter we extend to jb* - algebras, a classical result due to cleveland [8]. this result shows shows the weakness of jb* - norm topology on a jb* - algebera. in chapter three, ...

the quest for power has formed much of the world history especially in 20th and 21st centuries. oil (energy) particularly after industrial revolution has been a tool for conquest and power and has been transformed to a geopolitical issue. from a geopolitical point of view this has been the case for the last two centuries in central asia and caucasus. central asia and caucasus has always been...