in this thesis, we consider a mathematical model of cancer with completely unknown parameters. we study the stability of critical points which are biologically admissible. then we consider a control on the system and introduce situations at which solutions are attracted to critical points and so the cancer disease has auto healing. the lyapunov stability method is used for estimating the un...

the study of air infiltration into the buildings is important from several perspectives that may be noted to energy and design of hvac systems, indoor air quality and thermal comfort and design of smoke control systems. given the importance of this issue, an experimental and numerical study of air infiltration through conventional doors and windows has been explored in iran. to this end, at fir...

abstract: the potato tuberworm, phthorimaea operculella (zeller), is an important insect pest of potato (solanum tuberosum l.) in the storage and field in most parts of the world especially in tropical and subtropical regions due to its close relationship with the host, high reproductive potential and high economic losses. information on host preference, life table parameters and digestive en...

from its emergence till present time marxist principles has undergone great changes since their promulgation by marx. many theorists and thinkers set at rectifying marxist tenets and introducing those of their own while others advocated its main concepts and attempted at improving them. among marxist philosophers who had an intensive study of marxs ideology, is louis althusser whose reflections...

abstract since heubners (1985) pioneering study, there have been many studies on (mis) use/ non-use of articles by l2 learners from article-less and article languages. the present study investigated how persian l2 learners of english produce and interpret english definite descriptions and demonstrative descriptions. it was assumed that definite and demonstrative descriptions share the same cen...

a simple, sensitive and selective method for solvent extraction and spectrophotemetric determination of lanthanum (ii) europium (iii), and cerium (iii) is described , the rare earth metals are extracted into chloroform solution of n-phenylbenzohydroxamic acid (pbha) at ph 9-10 various parameters are studied to optimize the extraction conditions. the molar absorptivity is found to increase from ...

nowadays,tourism industry considered as one of the main sources of income of a country.unfortunately and despite of owning plenty of cultural historical and natural attractions, iran has not reached to a proper position in this field. besides, the historical cities of a country are considered as the income resource and national wealth of it. qazvin with a rich cultural precedent, have suitable ...

بررسی رابطه بین یادگیری سازمانی و توانمندسازی مدیران و معاونین مدارس شهرستان میانه دکتر محمد اورکی1، دکتر هاشم نعمتی، گلسیما عزیزی* استادیار گروه علوم تربیتی ، دانشگاه پیام نور تهران جنوب استادیار گروه علوم تربیتی. ، دانشگاه پیام نور مشهد دانشجوی کارشناسی ارشد مدیریت آموزشی ، دانشگاه پیام نور تهران جنوب [email protected] میانه- دانشگاه پیام نور میانه مدیر آموزشی، 2226062 – 0423، ت...

in his last years of life americans had almost forgotton steinbeck, and those who had not, occasionally criticized him for supporting and praising the u. s. military intervention in the vietnam war. althought ateinbeck incorporates different themes into his works, each one bears many signs of his concern and sympathy for america and the american common people in particular. steinbecks to a god ...

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 ...