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.
Despite the significant increase in women in academic medicine over the last 50 years, women are still under-represented in leadership positions in academia. However, there is a lack of data on the diversity of editorial boards in Middle Eastern medical journals. So, we aim to portray the diversity of editorial boards of Iraqi medical journals by conducting a cross-sectional analysis of the editorial boards’ members of all Iraqi medical journals. Gender, affiliation and specialty were extracted from the journals’ websites and/or from the professional profiles of the editorial board members. Twenty-five journals and 446 editorial board members were analysed. More than half of editorial board members specialized in basic scienc
... Show MoreNative speakers of English from different parts of the world have different accents,but the differences of accents are mainly the result of differences in the sound of vowels and consonants . The actual use of all these sounds in combination leads the speaker to produce a number of segments which only appear on the production level and realized on the perceptual one . RP pronunciation represents the teachable variety in all Iraqi universities because it is the most acceptable and understandable accent all over the world and not only in South East London ..The structure of the English syllable in RP pronunciation is influenced by the appearance of certain allophones especially aspiration and glottalization which ch
... Show MorePurpose: In view of the trend toward using international financial reporting standards when generating financial statements, we looked at the interaction between audit services and non-audit services for auditors in the context of actuarial services for insurance firms. CPAs are authorized to work in banks and insurance businesses, but those with a practicing license obtained after earning a higher academic degree are not. Design/methodology/approach: A small number of auditing firms control the decisions issued by the Iraqi Accountants Association, monopolizing audit services in banks and insurance businesses. In the case of actuarial services used in reserve estimation, they are credited to an external party's account withou
... Show MoreThis study offers additional evidence for the occurrence of oil residues within fractures of the basement rocks in the Upper Benue Trough, Nigeria. The data suggests that the observed oil residues were originally generated as light oils, which were later biodegraded into heavy oils. These Upper Benue Trough's oil stains are a valuable tool for hydrocarbon exploration in the region as they indicate the existence of a petroleum system in the basin. We find a strong similarity to the proportions of C27, C28, and C29 regular steranes of oils found in the sandstones and shales of the Bima Formation in the Upper Benue Trough when we plot the relative quantities of these steranes of the investigated basement rock oil types on a ternary gra
... Show MoreBackground: The dimensional change of alveolar ridge is normal effect of teeth extraction, with unfavourable functional and esthetical outcomes that might jeopardize implant placement. To reduce the biological effects of the dimensional changes of alveolar ridge, various surgical procedures have been recommended, called alveolar ridge preservation. In the previous decade, autogenously teeth have been proposed as bone graft substitution in fresh extraction socket with successful results, yet with various preparation protocols. Aim: Evaluate the formation of new bone derived from the freshly extracted teeth that are grafted immediately in the post extraction sockets, in comparison with sockets without graft filling, by using CBCT and to compa
... Show MoreThe public budget is on the same time an art and a science .As an accountable science it seeks balance between public income and public expenditure for an accountable year. And as an accountable art it seeks to achieve economic balance by distributing equitable income in order to reach sustainable development .This is the optimal use of all natural and human resources to address scarcity of natural resources facing the increase need of human resources by spending on education, health, environment, housing, agriculture and industry to achieve social justice for the current generation and future generations. Since the first budget in Iraq on 1921 an accounting budget, is balancing the sections and items has been adopted and since the publi
... Show MoreInternational relations scholars have increasingly debated the evolving landscape of actors that challenge the traditional state-centric world order. A key element of this transformation is the rise of sub-state actors, which engages in alternative diplomacy parallel to the state, transcending traditional state-centric frameworks. This paper explores the significant shifts in international actorness over the late 20th century, focusing on the emergence and implications of sub-state diplomacy, or "paradiplomacy." First, the study introduces sub-state actors and their role in challenging the dominant state-centric discourse. It then examines the dynamic evolution of paradiplomacy, highlighting how sub-states have expanded their global
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