a semi-empirical mathematical model for predicting physical part of ignition delay period in the combustion of direct - injection diesel engines with swirl is developed . this model based on a single droplet evaporation model . the governing equations , namely , equations of droplet motion , heat and mass transfer were solved simultaneously using a rung-kutta step by step unmerical method . the...

rivers and runoff have always been of interest to human beings. in order to make use of the proper water resources, human societies, industrial and agricultural centers, etc. have usually been established near rivers. as the time goes on, these societies developed, and therefore water resources were extracted more and more. consequently, conditions of water quality of the rivers experienced rap...

nowadays in trade and economic issues, prediction is proposed as the most important branch of science. existence of effective variables, caused various sectors of the economic and business executives to prefer having mechanisms which can be used in their decisions. in recent years, several advances have led to various challenges in the science of forecasting. economical managers in various fi...

چکیده هدف اصلی این پژوهش شناسایی الزامات نظام مدیریت کیفیت فراگیر در حوزه پژوهشی دانشگاه اصفهان بود. سوالهای پژوهش با توجه به مولفه های مدیریت کیفیت (تعهد مدیران، بهبود مستمر فرایندها ، مشتری محوری ، منابع انسانی ، مدیریت اطلاعات ، زیرساختهای کیفیت ، استفاده از نتایج ، انعطاف پذیری، مشارکت در فعالیتهای پژوهشی، ایجاد فرهنگ کیفیت و تناسب ساختارهای سازمانی) که بر اساس مطالعه استانداردهای بین المل...

in the area of vocabulary teaching and learning although much research has been done, only some of it has led to effective techniques of vocabulary teaching and many language learners still have problem learning vocabulary. the urge behind this study was to investigate three methods of teaching words. the first one was teaching words in context based on a traditional method of teaching that is,...

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...

the present study investigated construct equivalence of multiple choice (mc) and constructed response (cr) item types across stem and content equivalent mc and cr items (item type ‘a’), non-stem-equivalent but content equivalent mc and cr items (item type ‘b’), and non-stem and non-content equivalent mc and cr items (item type ‘c’). one hundred seventy english-major undergraduates completed mc ...

to teach english adequately, qualified teachers are needed. unfortunately, there are still teachers who are teaching english without an academic degree in tefl. it is necessary for teachers to have a major in english to have subject knowledge, but it is not sufficient. teachers need to have an understanding of the social, cultural, moral, ethical, and pedagogical issues of education and practic...

testing plays a vital role in any language teaching program. it allows teachers and stakeholders, including program administrators, parents, admissions officers and prospective employers to be assured that the learners are progressing according to an accepted standard (douglas, 2010). the problems currently facing language testers have both practical and theoretical implications but the first i...

the aim of this thesis is an approach for assessing insurer’s solvency for iranian insurance companies. we use of economic data with both time series and cross-sectional variation, thus by using the panel data model will survey the insurer solvency.