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...

according to webster and wind (1972) and anderson et al (1987), “organizational buying is a complex process and involves many people from different functional areas, multiple goals and potentially conflicting decision criteria. moreover, the customers of today are also more knowledgeable and selective when making their purchasing decisions. since a key to organizational survival is the retentio...

increasing academic and professional language demands around the world are not a deniable fact. the purpose of this study was to investigate english language needs and communication needs of the chemistry students at master and ph.d. levels at the iranian universities. in this research, different methods were used including un-structured interview, structured interview, and two sets of question...

this thesis basically deals with the well-known notion of the bear-invariant of groups, which is the generalization of the schur multiplier of groups. in chapter two, section 2.1, we present an explicit formula for the bear-invariant of a direct product of cyclic groups with respect to nc, c>1. also in section 2.2, we caculate the baer-invatiant of a nilpotent product of cyclic groups wuth resp...

muhammad ibn muhammad ibn numan, known as "shaykh mufid," one of the great imamiye theologians and jurists in the fourth and early fifth century , had comprehensive mastery of both rational and traditional topics and exerted his influence upon both his contemporary and future scholors. he is considered to be one of the top imamiye scholars who spent his lifetime teaching, learning and authorin...

کتاب تبصره المومنین(نگارش در سال1080ق) تالیف محمد مومن حسینی تنکابنی، جوابیه و ردّیه ای بر سخنان ملامحمد طاهر قمی در کتاب تحفه الاخیار است. این تحقیق تصحیح انتقادی و نقد وبررسی این کتاب است که نسخه مجلس شورای اسلامی اساس قرارداده شده و با سه نسخه دیگر مقابله شده است. نویسنده کتاب یکی از پزشکان دربار شاه سلیمان صفوی(1077) است. وی در عصری زندگی می کند که تصوف وصوفیان اگرچه درحمایت نسبی حکومت هستند...

the purpose of the present study is to find out whether bilinguals of khuzestan-arab origin or monolinguals of iranian origin code-switch during learning or speaking english and which group is more susceptible to code-switch. to this end, the students of 24 classes from high schools and pre- university centers were screened out, and interviewed and their voices and code-switchings were recorded...

it is definitely necessary to understand the concept and behavior of causation of life insurance policies and its determinants for insurance managers, regulators, and customers. for insurance managers, the profitability and liquidity of insurers can be increasingly influenced by the number of causation through costs, adverse selection, and cash surrender values. therefore, causation is a materi...