Bragg Reflectors consist of periodic dielectric layers having an optical path length of quarter wavelength for each layer giving them important properties and makes them suitable for optoelectronics applications. The reflectivity can be increased by increasing the number of layers of the mirror to get the required value. For example for an 8 layers Bragg mirror (two layers for each dielectric pair), the contrast of the refractive index has to be equal to 0.275 for reaching reflectivity > 99%. Doubling the number of layers results in a reflectivity of 99.99%. The high reflectivity is purely caused by multiple-interference effects. It can be analyzed by using different matrix methods such as the transfer matrix method (TMM) which is the simplest method to study the characteristic of devices with different alternating layers.
The current search aims to identify First: To measure the level of authoritarian personality among the students of the sample as a whole. Second: Measurement of differences in the level of authoritarian personality among students in the middle school according to the following variables 0.Science (literary, scientific) 8. Sex (male - female) Third: the level of control site level among the students of the sample as a whole. Ra'aa: Measurement of differences in the level of the control site among junior students according to the following variables 0.Science (literary, scientific) 8. Sex (male - female) Fifth: Explain the relationship between the authoritarian personality and the locus of control among the students of the research sample.
... Show Moreان تقدير مسؤولية المحاسب في تصميم نظام المعلومات المحاسبي من منظور تاريخي سبقت استخدام الحاسوب كأداة معلوماتية للاعمال، لما له من رؤيا بالتطورات الرئيسية لنظام المعلومات والتي اهمها تحديد متطلبات مستخدمي المعلومات وتعيين مضمون وشكل مخرجات النظام من التقارير وتحديد مصادر البيانات وانتقاء القواعد المحاسبية الملائمة فضلاً عن الرقابة الضرورية لتكامل وفاعلية النظام.
ان النظم المحاسبية التقليدية غالبا
... Show MoreDeveloped technologies and complementary means for viewing theater through the ages, and they affected would improve and get better. Valsinogravea appeared to express a description and identification of existing in the theatrical space of lighting and decorative structure architecture, and the lighting of the elements that have contributed since ancient times in the process of the show, and played a significant role in strengthening the relationship between the recipient and actor and presentation theater as a whole scenes, working to broadcast a dramatic speech theatrical holds ideas and content and symbols and semantics affect the spectator of different age, particularly the child viewer, that little spectator who represent the
... Show Moreتركز هذا البحث على تصميم عدسة كهروستاتيكية ثلاثية الاقطاب اسطوانية الشكل متحدة المركز ومفصولة بفتحة هوائية . تم حل معادلة لابلاس بطريقة كثافة الشحنة في مجال بصريات الجسيمات المشحونة اللانسبية وبغياب تأثيرات شحنة الفضاء إن توزيع الجهد المحوري لعدسة ثلاثية كهروستاتيكية تم حسابه باستخدام كثافة الشحنة الموزعة على الاقطاب، الناتجة من تسليط فولتية معينة على الاقطاب اعتمادا على ق
... Show More