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.
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Banks face many of the various risks: which are of dangerous phenomena that cause the state achieved a waste of money and a threat to future development plans to be applied to reach the goals set by: prompting banks and departments to find appropriate solutions and fast: and it was within these solutions rely on Banking risk management and effective role in defining and identifying: measuring and monitoring risk and trying to control and take risks is expected to occur in order to encircle and make it in within acceptable limits: and try to avoid them in the future to reduce the losses that are likely to be exposed to the bank: and it began to emerge and dominate a lot of legislation that seeks to structure the year risk management and t
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In the present study the radon concentration was measured in indoor places by the RAD7 (radon detector) was in some locations at Al-Tuwaitha nuclear site and some surrounding areas for the duration from 13/10/2016 to 2/1/2017 and the measurement of the indoor radon concentration ranged from (4.96±4.4 to 102±25) Bq/m3. The high value of radon has been found at decommissioning directorate /emergency room, which is lower than the action value recommended by the Environmental Protection Agency (EPA) which is (148 Bq/m3) while the lowest value has been founded in central laboratories directorate \ models room. These values were used to calculate the annual effective dose and the health risks for cells bronchial which caused by the inhalatio
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Objective The incidence of rhythm and conduction abnormalities during acute myocardial infarction may approaches 100%; most are seen during the pre-hospital and coronary care unit phases, leading to deleterious effect on morbidity and mortality, this study conducted to find important persistent dysrhythmia found during CCU admission of acute myocardial infarction patients.Method A retrospective observational study of 553 patients who were admitted to the Coronary Care Unit of Alkindy Teaching Hospital during Year 2011 with diagnosis of acute myocardial infarction, Information and data extracted from case sheets and associated 12 leads daily ECGsResults only 25% of our patients had dysrhythmia on examining the present 12 leads ECGs , the
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The current research aims to identify the level of partnership between school and community agencies to improve secondary school outcomes for students with intellectual disabilities and develop strategies that help enhance community partnerships between schools and agencies. The researcher used the qualitative research approach; he utilized the interviews as a tool for data collection. The sample of research included (12) participants: three female school leaders, three male-school leaders, three female-school supervisors, and three male-school supervisors in schools that have programs for students with intellectual disabilities in Riyadh. The results of the study showed that the level of partnership bet
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