The Cepheid Data Base

مقدمه ای بر: تکنولوژی data base و اداره سازمان

در ادراه امور سازمان نیز از تکنولوژی data base در دو زمینه مشخص یعنی بصورت سیستم های عملیاتی و سیستم های اطلاعاتی میتوان استفاده کرد. در شرایط کنونی وجود موانع متعدد از قبیل فرهنگ غالب در سازمان های بزرگ و طرز تلقی مدیران دیوان سالار از یکطرف و تازه گی و پیچیده بودن فنون مربوط به سیتم های data base فقدان دانش، تجربه و تخصص کافی برای بهره گیری کامل از آن از طرف دیگر، برنامه ریزی و اقدام برای ایج...

Bayesian Analysis of Cepheid Variable Data

Cepheids are a type of variable star that play a key role in establishing the astronomical distance scale. These objects undergo regular pulsations, shrinking and expanding as their luminosities and colors vary in synchronism. It has long been known that the period of the pulsation is related to the luminosity of the star (the Period-Luminosity relationship), and therefore these objects become ...

the comparison between global and regional precipitation data base with iran asfezari and station data base

nowadays, undoubted access to up to date with high spatial resolution and low temporal resolution of meteorological parameters is a one of the necessary needs for meteorological science researches. in order to doing this research have been used the different daily, monthly and yearly iran precipitation from global and regional data base of gpcpøŒ gpccøŒ aphrodit v101 0.25øŒ aphrodit v101 0.5 ùˆ...

The Cepheid Luminosity Scale

The anomalous Cepheid XZ Ceti

Aims. XZ Ceti is the only known anomalous Cepheid in the Galactic field. Being the nearest and brightest such variable star, a detailed study of XZ Ceti may shed light on the behaviour of anomalous Cepheids whose representatives have been mostly detected in external galaxies. Methods. CCD photometric and radial velocity observations have been obtained. The actual period and amplitude of pulsati...