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.
Undoped and Iodine (I)–doped chrome oxide (Cr2O3)thin films have been prepared by chemical spray pyrolysis technique at substrate temperatures(773K) on glass substrate. Absorbance and transmittance spectra have been recorded as a function of wavelength in the range (340-800 nm) in order to study the optical properties such as reflectance, Energy gap of allowed direct transition, extinction coefficient refractive index, and dielectric constant in real and imagery parts all as a function of wavelength. It was found that all the investigated parameters affect by the doping ratios.
This work aims to study the exploding copper wire plasma parameters by optical emission spectroscopy. The emission spectra of the copper plasma have been recorded and analyzed The plasma electron temperature (Te), was calculated by Boltzmann plot, and the electron density (ne) calculated by using Stark broadening method for different copper wire diameter (0.18, 0.24 and 0.3 mm) and current
of 75A in distilled water. The hydrogen (Hα line) 656.279 nm was used to calculate the electron density for different wire diameters by Stark broadening. It was found that the electron density ne decrease from 22.4×1016 cm-3 to 17×1016 cm-3 with increasing wire diameter from 0.18 mm to 0.3 mm while the electron temperatures increase from 0.741 to
Recommender Systems are tools to understand the huge amount of data available in the internet world. Collaborative filtering (CF) is one of the most knowledge discovery methods used positively in recommendation system. Memory collaborative filtering emphasizes on using facts about present users to predict new things for the target user. Similarity measures are the core operations in collaborative filtering and the prediction accuracy is mostly dependent on similarity calculations. In this study, a combination of weighted parameters and traditional similarity measures are conducted to calculate relationship among users over Movie Lens data set rating matrix. The advantages and disadvantages of each measure are spotted. From the study, a n
... Show MoreThe research aims to identify the concept of financing structure and what are the determinants that affect it and the goals achieved by financing in commercial banks in addition to the sources upon which the financing structure depends consisting of internal financing sources and external financing sources and their connection to the profits of commercial banks. Baghdad, Khaleeji Commercial Bank) registered in the Iraq Stock Exchange during the period for the years (2011-2020) published in the Iraq Stock Exchange from and the research relied on financial analysis tools to analyze the independent variable the following financing structure (the ratio of equity to total assets, the ratio of deposits to Total liabilities, the ratio of loans
... Show MoreCeramic coating compose from a ceramic mixture (MgO, Al2O3) and metall (Al-Ni) were produced by Thermal Spray Technique. The mixed ratio of used materials Al:Ni (50%) and 40% of Al2O3 and 10% MgO. This mixture was spray on a stainless steel substrate of type (316 L) by using thermal spray with flame method and at spraying distances (8, 12, 16 and 20) cm, then the prepared films were treated by laser and thermal treatment. After that performing a hardness and adhesion tests were eximined. The present study shows that the best value of the thermal treatment is 1000 ℃ for 30 mint; the optimum spray distance is 12 cm and most suitable laser is 500 mJ where the microscopic and mechanical character
... Show MoreThe research dealt with the impact of reinsurance on the financial surplus of the National Insurance Company by focusing on reinsurance in the marine insurance / merchandise branch. The aim of this research was to show the impact of reinsurance indicators (reinsurance ratios, retention ratios, commission rates earned) on reinsurance operations Data on the research variables were collected based on the inductive and deductive approach in the analysis of information for the financial reports of the National Insurance Company of the Marine Insurance Branch and the insurance portfolio (goods) for the period from 2010 to 2017, and for the purpose of obtaining results was used M a number of statistical methods commensurate with the nature of t
... Show MoreJava is a high-level , third generation programming language were introduced Javaoptics Open Source Physics (OSP) as a new simulation for design one of the most important interference optical coating called antireflection coating. It is recent developments in deign thin-film coatings. (OSP) shows multiple beam interferences from a parallel dielectric thin film and the evolution of reflection factors. It is simple to use and efficiently also can serve educational purposes. The obtained results have been compared with needle method
Non thermal argon plasma needle at atmospheric pressure was constructed. The experimental set up was based on simple and low cost electric components that generate electrical field sufficiently high at the electrodes to ionize various gases which flow at atmospheric pressure. A high AC power supply was used with 9.6kV peak to peak and 33kHz frequency. The plasma was generated using two electrodes. The voltage and current discharge waveform were measured. The temperature of Ar gas plasma jet at different gas flow rate and distances from the plasma electrode was also recorded. It was found that the temperature increased with increasing frequency to reach the maximum value at 15 kHz, and that the current leading the voltage, which demonstra
... Show More