Population I Stellar Structure and Evolution: facing the lingering difficulties to make a step forward

An Enhanced Flux Treatment in Solving Incompressible Flow in a Forward-Facing Step

The aim of this paper is to give a detailed effect of several parameters such as step height, Reynolds number, contraction ratio, and temperature difference between the entrance and solid boundaries, of a forward-facing step. An accurate length of separation and reattachment zones are achieved. A finite-volume method (FVM) has been developed to study incompressible flow in a forward-facing step...

Stellar Structure and Evolution

"X-ray vision" and the evolution of forward-facing eyes.

Why do our eyes face forward, and why do many mammals have eyes facing sideways? Here, we describe results suggesting that the degree of binocular convergence is selected to maximize how much the mammal can see in its environment. Mammals in non-cluttered environments can see the most around them with panoramic, laterally directed eyes. Mammals in cluttered environments, however, can see best w...

Presupernova Evolution of Rotating Massive Stars I: Numerical Method and Evolution of the Internal Stellar Structure

The evolution of rotating stars with zero-age main sequence (ZAMS) masses in the range 8M⊙ to 25M⊙ is followed through all stages of stable evolution. The initial angular momentum is chosen such that the star’s equatorial rotational velocity on the ZAMS ranges from zero to ∼ 70% of break-up. The stars rotate rigidly on the ZAMS as a consequence of angular momentum redistribution during the pre-...

the underlying structure of language proficiency and the proficiency level

هدف از انجام این تخقیق بررسی رابطه احتمالی بین سطح مهارت زبان خارجی (foreign language proficiency) و ساختار مهارت زبان خارجی بود. تعداد 314 زبان آموز مونث و مذکر که عمدتا دانشجویان رشته های زبان انگلیسی در سطوح کارشناسی و کارشناسی ارشد بودند در این تحقیق شرکت کردند. از لحاظ سطح مهارت زبان خارجی شرکت کنندگان بسیار با هم متفاوت بودند، (75 نفر سطح پیشرفته، 113 نفر سطح متوسط، 126 سطح مقدماتی). کلا ...