for a given riemannian manifold (m,g),it is an interesting question to study the existence of a conformal diffemorphism (also called as a conformal transformation) f : m ! m such that the metric g? = fg has one of the following properties: (i)(m; g?) has constant scalar curvature. (ii)(m; g?) is an einstein manifold.

هدف این پایان نامه تعیین تعداد مولدهای مینیمال ایده آلها در یک حلقه (جابجایی، یکدار، موضعی و نوتری) است، هر چند تعیین دقیق تعداد مولدها در حالتهایی خاص امکان پذیر است اما در حالتهای کلی روش های موجود بدست آوردن کرانهای مختلف برای تعداد مولدها است. مرجع اصلی این پایانامه ‏‎[1]‎‏ می باشد، به علاوه از نتایج جدیدی که در مرجع ‏‎‏‎[2]‎‏ نیز آمده استفاده کرده ایم. ‏‎[1]. j. sally. numbers of generator...

reserches show that relationship between human and residential places is based upo both emotional and identity structures. in other words, habitat place is not only the creator of a part of humanistic identity but also form a kind of sentimental and emotional bond that may result in tendency to maintain closeness to a specific place. therefor, formaton of emotional and identity relationship wit...

peace and national security protection and ironic solving of international conflicts become the preliminary foundation of the united nations charter and had been considered as the main responsibilities of the security council, after world war ii and the establishment of united nations organization. therefore, the security council enables to analyze every kind of conflicts and challenges which ...

data envelopment analysis (dea) is a powerful tool for measuring relative efficiency of organizational units referred to as decision making units (dmus). in most cases dmus have network structures with internal linking activities. traditional dea models, however, consider dmus as black boxes with no regard to their linking activities and therefore do not provide decision makers with the reasons...

abstract english language learning in iran has become significant in recent years, and english has been included in the curriculum of iranian schools and universities, and considerable attention has been paid to this language in our society. nevertheless, teaching and learning english in iranian schools has not been able to satisfy the specified goals, so different efl institutes have been est...

the present thesis is a study of postmodern historical novel with respect to the voice of women. according to postmodern historiography,the established institution of history is one of the other manifestations of patriarchys power which has silenced women. the study analyzes angela carters nights at the circus as a postmodern historical novel which makes its female characters transgress the pat...

a simple, rapid and low-cost scanner spectroscopy method for the glucose determination by utilizing glucose oxidase and cdte/tga quantum dots as chromoionophore has been described. the detection was based on the combination of the glucose enzymatic reaction and the quenching effect of h2o2 on the cdte quantum dots (qds) photoluminescence.in this study glucose was determined by utilizing glucose...

with the introduction of communicative language teaching, a large number of studies have concerned with students’ oral participation in language classrooms. although the importance of classroom participation is evident, some language learners are unwilling to engage in oral activities. this passivity and unwillingness to participate in language classroom discussions is known as “reticence”. rev...

in this work, a novel and fast method for direct analysis of volatile compounds (davc) of medicinal plants has been developed by holding a filament from different parts of a plant in the gc injection port. the extraction and analysis of volatile components of a small amount of plant were carried out in one-step without any sample preparation. after optimization of temperature, extraction time a...