Bending effects on the transmission of optical signal are investigated on a single mode
optical fiber (SMOF) of 10 m length, core radius of 5 μm and optical refractive index difference
0.003. The bending radii (R) were between 0.08 and 0.0015 m. A great decrease in the amplitude is
shown for radii below 0.01 m. Sudden break down occurs for radii less than 0.0015 m. Birefringence
(B) is difficult to measure for long fibers. Meanwhile, B was found by comparing with calibrated
fiber of the same properties but of length of 0.075 m. The results show an increase in propagation
constant (Δβ) and the decrease in beat length (Lb), and show that bending decreases the critical radius
of curvature (Rc) related to B. The changes induced on the initial phase of the signal are shown for
bending curvatures of radii 0.06, 0.03 and 0.005 m. The linear phase retardation is found to increase
more rapidly for bends of R< 0.05 m. The degree of polarization decreases smoothly for bends of
R>0.01m. Below this curvature, the fluctuation and great instability in the polarization- state of the
output signal are easily detected. All these features are very important in using SMOF in sensitive
optical devices especially in long distance fiber communications.
ملخص البحث: يعد اسلوب تدريب المقاومات المرنة واحد من اساليب تدريب القوة العضلية فهو النظام الذي يتم من خلاله استخدام تمرينات يتم ادائها ضد مقاومات متغيرة مثل الحبال المطاطية او اشرطة الساندو، ويمتاز هذا الاسلوب بتغير الشدة خلال اداء التمرين الواحد اي ان كلما تم مط الحبل المطاطي ازدادت مقاومته وبالتالي فان اللاعب يستخرج قوته اكثر كلما اقترب الى مركزية الحركة في التمرين وهذا هو جوهر الاختلاف بينه وبين استخد
... Show MoreThe research aims to diagnose the level of reflection of uncertainty management strategies (Ignoring uncertainty, knowledge generation , interaction , coping) managing of Organizational change strategies (power coercive, rational empirical, Normative reductive) to the importance of the two subjects and the importance of the expected results has been selected sample size (65) managers from Zain , Asia Cell Telecommunication (32 Zain and 33 company Asia),which alignment for the such a study being heavily dependent on the certainty or uncertainty subject . The researchers are attain there is the effect of uncertainty management strategies in Organizational change management strategies on the overall level in the two companies but have tended t
... Show Moreالملخص: تعد عناصر اللياقة البدنية العمود الفقري للألعاب الرياضية وخصوصا في الالعاب الجماعية ومنها لعبة كرة القدم للصالات والتي تعد من الالعاب الرياضية التي تتطلب بذل جهود كبيرة خلال المنافسة نظرا لطبيعة الاداء الذي يمتاز بالقوة والسرعة طيلة شوطي المباراة وهذا يتطلب من اللاعب امتلاكه للياقة بدنية عالية تؤهله للإيفاء بهذه المتطلبات خلال المنافسة، لذا نجد المدربين يتبعون كافة الاساليب وطرائق التدريب في سب
... Show Moreتتطلب عملية التنمية الاقتصـادية في الدول النامية مبالغ كبيرة من رؤوس الأمـوال اللازمة لتنفيذ البرامج والخطط الاقتصادية، ولما كانت الاسـتثمارات التي تنفذها هذه الدول خلال حقبة معينة، تزيد على ما تم تحقيقه من موارد مالية محلية، فلابد أنْ يمول الفرق من خلال انسياب صافٍ لرأس المال الأجنبي (قروض ومساعدات) إلى الداخل خلال المدة نفسها، لغـرض سَدّ الفجوة في المـوارد المحلية المعدة للاسـتثمار، وعانت بعض د
... Show MoreAbstract
Due to increased interest on organizations and the human element, organizational and environmental aspects of the organization Has been analyzed, and behavioral aspects of the members and what is the impact of each on the other, To give the recipe interaction between the organization and its environment, in order to bring about change in behavior appeared the concept of organizational health as a concept in a modern organizations, Either the organization to be stimulating good, healthy, and then called healthy organization Or that the situation be frustrating it is not good and unhealthy, so the cause of tension and anxiety, unhealthy organization is here The research aim to determine the existence of organizatio
... Show MoreBackground: Analysis of human reports and comparison with results of experimental animals indicate that the effects of progesterone on human not analogous to experimental animals fetus, many studies showed that exposure to progesterone during developing of genital tract of human fetus was not teratogenic. Other studies which performed on laboratory animals found association between progesterone administration during gestation and genital malformation. Objectives: to explore the effect of progesterone in 10.2 mg/kg intraperitoneal injection in mice on testis development and anogenital distance. Materials and Methods: ten pregnant mice divided into five mouse control group that injected10. 2mg/kg sesame oil and treated group that injected pro
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