abstract: in the paper of black and scholes (1973) a closed form solution for the price of a european option is derived . as extension to the black and scholes model with constant volatility, option pricing model with time varying volatility have been suggested within the frame work of generalized autoregressive conditional heteroskedasticity (garch) . these processes can explain a number of em...

  Since forest parks have high importance in urban environment, evaluation of outdoor recreation potential and identification of the suitable regions for outdoor recreation usage in forest parks is necessary . In this research, the suitable areas for intensive and extensive outdoor recreation, their various degrees and outdoor recreation potential of Sorkhehesar forest park was identified using...

چکیده : تحقیق حاضر به منظور مقایسه دو روش تدریس انتزاعی و تدریس در متن بر یادگیری دستور زبان ایتالیاییِ زبان آموزان ترم 1 مدرسه ایتالیایی تهران در تابستان 89 صورت گرفت. روش تحقیق آزمایشی بوده و پژوهش بر 30 نفر از زبان آموزان مدرسه ایتالیایی تهران که بصورت تصادفی به 2 گروه جایگزین شدند صورت گرفت. ابزار تحقیق آزمون 30 سوالی تستی از بانک سوالات استاندارد شده بود که به تصادف انتخاب شده بودند.روشهای...

the present dissertation aims to investigate four-word lexical bundles in applied linguistics research articles by iranian and internationally-published writers. the aims of this study are two-fold: first of all, attempts have been made to create a comprehensive list of the most commonly used four-word lexical bundles categorized by their type and token frequency, their structural characteristi...

attempts have been made to study the thermodynamic behavior of 1,3 butadiene purification columns with the aim of retrofitting those columns to more energy efficient separation schemes. 1,3 butadiene is purified in two columns in series through being separated from methyl acetylene and 1,2 butadiene in the first and second column respectively. comparisons have been made among different therm...

Mapping of forest extent is a prerequisite to acquire quantitative and qualitative information about forests and to formulate management and conservation strategies. forest canopy density (FCD) model is one of the useful RS methods for forest mapping using satellite images. One of the most serious challenges in FCD model is the weakness in the calculation of canopy density in low density forest...

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 ...

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...