Birth-death processes have been widely used for different biological applications, the most common of which is stochastic modeling of population dynamics. A review of these applications can be found in Novozhilov et al. (2006). In this letter we illustrate a method to obtain approximate formulae for the steady-state mean and variance, of a birth death process involving a single species with arb...

امروزه در مبحث محاسبات رآکتورهای هسته‌ای مثل فرسایش و مدیریت سوخت، تحلیل گذرا بازسازی توان میله‌های به دنبال روش‌هایی جهت استفاده کدهای هستند که علاوه بر دقت قابل‌قبول از هزینه زمان بهینه‌ای برخوردار باشند. این پژوهش با گسسته‌سازی معادله پخش نوترون روش نودال بسط شار جریان ‌متوسط مرتبه بالا نشان داده می‌شود روش‌ بهینه قابل‌قبولی بهره می‌برد. مستقیم الحاقی نوترون، برای هندسه مربعی دوبعدی دو گروه ...

Plates and shells represent principal elements of aerospace structures, including fuselages of planes and missiles, control surfaces, bulkheads, helicopter blades, and others. The multiple applications, shapes, and materials found in plate and shell structures dictate the necessity of a comprehensive approach to their analysis reflected in relevant theories and methodologies. Various aspects of...

The Middle Cambrian Spence Shale Member (Langston Formation) and Wheeler and Marjum Formations of Utah are known to contain a diverse soft-bodied fauna, but important new paleontological material continues to be uncovered from these strata. New specimens of anomalocaridids include the largest and smallest near complete examples yet reported from Utah. New material of stem group arthropods inclu...