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.
The Arab literature in Andalusia was distinguished by its special nature, in addition to the distinction of its influencing rhythm in our souls, it represents the natural extension of the Arab-Islamic civilization in Morocco, that civilization that collapsed with insecurity and stability and the exit of Muslim Arabs from those countries and the defeat of Muslims, their civilization has ceased, and only remains of them witnessing For its leaders in a safe and stable life, but literature in Andalusia underwent many experiences that express the lives of Arab Muslims there, especially what distinguished the Andalusian Muslims from their many battles and conquests, but they did not suffer as their support during the fall of Andalusia and the
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The prophet said that it anybody burdened any of the people or the book more than they could endure he would ben his opponent until the day of judgment.
-under the rightly guided caliphs the Christians had much freedom .this is shown by a letter attributed to ishu-yab III. The Nestorian catholics.
-The third caliph,Uthman favoured the Christians either because of the spcial skills or abilities which they possessed or through the imfluence of his Christian wife Na'ila.
-Under the early Umayyade,the christiansins the Isalamic umma had as much freedom as they had previously enjoyed under the best of their Christians governments because they restorted their churches and appointed many Christians to the
... Show MoreThe present study included the effect of chronic exposure for two concentrations of NaC? salt on the biology of fresh water zooplankton species Brachionus calyciflorus (from ^otifera). The concentrations 0.5 , 0.75%o were used for chronic exposure to investigate its effects on the life tables, range of the rate of expectation for further life and reproduction. The rotifer B. calyciflorus was sensitive to salinity and may tried to protect the species by increasing the size (2.22 ind./clutch lor control group and 2.9? for 0.5%o concentration) and number of clutches produced ?.1? clutch/female for control group and 2.9 ' ' ' for 0.75 %0 concentration) beside stimulation the animal to produce the first clutch of eggs earlier? ? small reduction
... Show MoreThis study investigates the challenges encountered by first-grade intermediate students in learning the Arabic language. It aims to identify specific obstacles that hinder language acquisition and proficiency among this demographic. Through qualitative and quantitative methods, including surveys and interviews with students, teachers, and parents, the research highlights key issues such as limited vocabulary, difficulties in grammar, lack of engagement with the material, and inadequate teaching resources. The findings reveal a complex interplay between cognitive, social, and educational factors that contribute to these challenges. The study underscores the need for targeted interventions, such as enhanced pedagogical strategies and improved
... Show MoreEndometriosis is an estrogen dependent inflammatory disorder plays a pivotal role in the reproductive system of the females which regarded as one of the most important gynecological disorders due to it is a key cause of infertility for women and also it has a remarkable impact on the women's life quality. Indeed, environmental pollution have an extremely importance in the etiology of endometriosis. Hence, the present article submits an abbreviated literature review to the biochemical role of environmental pollutants in the etiology and development of endometriosis. Anyway, this review article represented the major environmental pollutants: the organic pollutants of air, heavy metals, gaseous pollutants and the particulate matter. Th
... Show MoreIn this paper, we studied the resolution of Weyl module for characteristic zero in the case of partition (8,7,3) by using mapping Cone which enables us to get the results without depended on the resolution of Weyl module for characteristic free for the same partition.
Buzurgan oil field suffers from the phenomenon of asphaltene precipitation. The serious negatives of this phenomenon are the decrease in production caused by clogging of the pores and decrease in permeability and wettability of the reservoir rocks, in addition to the blockages that occur in the pipeline transporting crude oil. The presence of laboratories in the Iraqi oil companies helped to conduct the necessary experiments, such as gas chromatography (GC) test to identify the components of crude oil and the percentages of each component, These laboratory results consider the main elements in deriving a new equation called modified colloidal instability index (MCII) equation based on a well-known global equation called colloidal instabi
... Show MoreThe upbringing of Yehuda Amichai and the conditions he lived in had a great influence on his deep sense of pain, which made him think of death and suicide. Especially after the Nazis came to power in Germany, and his emigration with his family. Amichai searched for love throughout his life, and his failure was one of the most important factors affecting his psyche, which is A deep influence that made him live in harsh and painful pains that broke him, and prevented her from achieving his ambitions in life.Dramatic texts are characterized by repetition in writing and presentation. It is a textual discourse that has two advantages, first, that it can be read as a literary text like all other literary texts, and second, that it can be consider
... Show MoreA vector in a separable infinite dimensional Hilbert space is called disk-cyclic for bounded operator if the orbit α : 0, α∈;|∝| 1is dense in. The useful tool used to discover codisk-cyclic operation is called the disk-cyclic Criterion. In this paper we will show that some equivalent conditions of the