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...

this study was conducted to investigate the impact of podcasts as a learning and teaching tool on iranian efl learners’ motivation for listening as well as on their listening comprehension ability. the study also investigated the learners’ perception towards listening to podcasts and examined whether the learners were likely to accept podcasts. out of fifty-five intermediate learners studying e...

abstract the first purpose of this study was to investigate the effect of consciousness-raising (c-r) activities on learning grammatical structures (simple present tense in this case) by iranian guidance school efl learners. the second one was to investigate the effect of gender on learning the simple present tense through c-r activities and tasks. finally, this study aimed to investigate the ...

learning a second or foreign language requires the manipulation of four main skills, namely, listening, reading, speaking, and writing which lead to effective communication. it is obvious that vocabulary is an indispensible part of any communication, so without a vocabulary, no meaningful communication can take place and meaningful communication relies heavily on vocabulary. one fundamental fac...

the purpose of this study was to investigate the effect of task repetition on accuracy of iranian efl learners ’speaking ability. in order to achieve this purpose, a null hypothesis was developed: there is no statistically significant difference between accuracy speaking ability in iranian efl learners by use of task repetition. ; of course i should mention that, beside this null hypothesis, an...

august wilson is undoubtedly one of the rare black playwrights whose works have attracted streams of attention and worldwide audience. the present study aims at analyzing fences and piano lesson which are two of the most successful plays in his pittsburgh cycle from the perspective of michel foucault’s theories and ideas. studying these two plays from foucault’s perspective opens new windows in...

abstract biometric access control is an automatic system that intelligently provides the access of special actions to predefined individuals. it may use one or more unique features of humans, like fingerprint, iris, gesture, 2d and 3d face images. 2d face image is one of the important features with useful and reliable information for recognition of individuals and systems based on this ...

cml in breif cml is characterized by the proliferation of large numbers of immature wbc in the blood and bone marrow. in most of the patients , it is a clonal disorder in which all cell lines, express the philadelphia chromosome)q/22 translocation(it accounts for 20 of all leukemias and most cases occur over 25 yrs of age. the disease usually begins insidiously,but symptoms referable to anemia ...

abstract this thesis includes five chapter : the first chapter assign to establish fuzzy mathematics requirement and introduction of liner programming in thesis. the second chapter we introduce a multilevel linear programming problems. the third chapter we proposed interactive fuzzy programming which consists of two phases , the study termination conditions of algorithm we show a satisfac...

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...