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.
This study focuses on the basics of cultivation and production of the Wheat Crop in
Wasit Province ; in order to reveal the reality of the geographical distribution of its cultivation
and production.
Wheat is the most important field crops cultivated in Wasit province, as it has vast
possibilities for expansion in growing and production, in which agriculture conducted in a
year and left in other , then changing this method would increase cultivated area of it to nearly
doubled, as well as the possibility of increasing average yields in Donam by using improved
seeds, fertilizer, with the availability of water lever machines, especially wheat is grown in
areas of rivers abutment.
The study showed the spread of th
In this paper, we used maximum likelihood method and the Bayesian method to estimate the shape parameter (θ), and reliability function (R(t)) of the Kumaraswamy distribution with two parameters l , θ (under assuming the exponential distribution, Chi-squared distribution and Erlang-2 type distribution as prior distributions), in addition to that we used method of moments for estimating the parameters of the prior distributions. Bayes
LO Hamza, NA Al-Mansor, J. Entomol. Zool. Studies, 2017 - Cited by 14
This study examines the validity of e-poetry as an acceptable literary genre. The
thematic, stylistic and esthetic features of a selected number of e-poems produced by
poetry generators are analyzed for this purpose. The e-poems are then compared with a
number of works written by Dada poets in order to establish the literary merit of the
former.
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The Research deals with the negative phenomena which appeared in the urban scenes of the Iraqi cities after 2003, particularly trespassing the architectural design of the urban Individual houses. Many academic researchers , critics, and cultural circles, drawn attention to the impact of political and cultural variable change on such phenomena without detailed analysis . The research problem is set according to central questions : If the phenomena is the trespass , what
are the sides which are being trespassed in the division of the individual house? , If the diagnosis of the phenomena denotes perceived repetition of the cases , So what's size of this transposes on the architectural design of t
Stealth marketing is considered as one of the contemporary issues that researchers have begun to explore as a current understanding. It is the marketing approach used by organizations to promote their products and services to the public in implicit and indirect manner. In this article, the concept of stealth marketing will be discussed throw its advantages and disadvantages. In addition, the different techniques of stealth marketing have been discussed including: viral marketing, celebrity marketing, brand pushers, bait-and-tease marketing, video games marketing, and marketing in music. Furthermore, a new technique of marketing entitled “Marketing through social responsibility” has been added and discussed according to the themes in the
... Show MoreA survey conducted at Dalmaj marsh, Al-Diwaniya Province during 2013 revealed that the marsh encounters a considerable part of the Iraqi vertebrate fauna including 147 species belonging to five classes; Pisces, Amphibia, Reptilia, Aves and Mammalia. Some species are of globally conservation importance. The present results are discussed with the pertinent literature.
Estimation of the names and verbs of some letters to consider the grammatical industry