This paper is concerned with an original analysis of an multiple pulse
position modulation (MPPM) scheme using graded-index plastic optical
fiber.
this research studies 2x2 MIMO LTE signal transmission from the
main tower eNB and the relay node RN over single mode fiber
using ROF technology and take advantage of the WDM technology,
the results show the ability of ROF to accommodate MIMO
com
munication with high efficiency.
The network has been simulated and analyzed using Optisystem
program, and the results were more than promising.
the best utilization of raw material for manufacturing the optimum
quality of yarn has become inevitable for the spinning mills to face
the global competition.
mechanical properties of yarn are of the most important properties
from quality point
of view and largely depend upon the fiber length
and micronair value ; which are considered the foremost quality
parameters for the selection of raw material .
it is the purpose of this study to investigate the effect of cottons
differing fiber length and micronair value on mechanical propeties
of yarn so as to contribute in determining the optimum using of the
raw material .
research The aim of this is to find an explicit relationship between the strength of fibers, bundle and
yarns. The CV values of the strength are given as well. This provides a relatively simple method for
estimation of staple yarn strength, while a
voiding some difficulties of an empirical method. The effects of
important factors such as fiber length and thickness, twist and count of yarn are considered. The results
are verified by published data in Mechanical Engineering of Textile Industries and Their Technologies,
Faculty of Mechanical and Electrical Engineering, Damascus University. and also in Al-Kumasiah
company in Damascus city.
This research provides suggestions if we apply it it will help in estimating directly the yarn strength
without manufacturing and suitable testing of the yarn.
A Photonic Crystal Fiber (PCF) is a special class of optical fibers which is made of a single material
and having air holes in the cladding. This paper studies and compares the optical characteristics such as
effective area, confinement loss and no
nlinearity, among three different PCF's structures: Hexagonal PCF (HPCF),
Octagonal PCF (O-PCF) and Decagonal PCF (D-PCF) with varied structural parameters (number of
the air-holes rings, the air-hole's diameter, and the lattice constant), and the target is to use the fiber in a
Raman amplifier. Proposed structures are simulated by using COMSOL MULTIPHYSICS which depends on
Finite Element Method (FEM).
The numerically simulated results shows that Decagonal PCF (D-PCF) offers lower confinement loss,
lower effective area, and larger value of nonlinearity than the other two structures. It is seen that Decagonal
PCF(D-PCF) is suitable for long transmission fiber applications.
جرت هذه الدراسة على 78 مريضاً و تم تقييم نتائجها من خلال 57 مـنهم اسـتمروا فـي
المتابعة، خضعوا جميعاً لعملية جراحة جيوب تنظيرية بسبب إصابتهم بداء البوليبات الأنفية
المتعدد (Polyposis nasal) ، بالتهاب جيوب مزمن (sinusitis chronic) . و قد تـم تطبيـق
مادة الميتومايسين c في نهاية العمل الجراحي داخل إحدى الحفرتين الأنفيتين الخاضـعتين
للجراحة و كانت دائماً اليسرى و قد اعتمد بروتوكول مشابه لبروتوكول مجرى فـي دراسـة
عالمية حديثة مع تعمد تطبيق المادة الدوائية بالتركيز نفسه الموصى به و إنما لفترة أطول.
كما أنه في دراستنا خلافاً للدراسة الأخرى فقد جرى اختبار تأثير هذه المـادة أيضـاً فـي
المرضى الخاضعين لعمل جراحي بسبب إصابتهم بداء البوليبات الأنفية، و هو الأكثر مشاهدة
لدينا من بين الأمراض المعالجة بجراحة الجيوب التنظيرية.
و قد خلصت هذه الدراسة إلى تأكيد فائدة هذه المادة الدوائية و لا سيما فيما يتعلق بإنقاصـها
لاحتمال النكس في داء البوليبات الأنفية و تشكل التندبات و الالتصاقات المرضـية و تضـيق
فتحات الجيوب. كما خلصت أيضاً إلى بعض النتائج الأخرى التي يمكن أن تعود بالفائدة على
هذه الجراحة و مجال استخدام هذه المادة فيها.
