Preferred Language
Articles
/
bsj-2538
Comparison between Direct and Coherent Optical Communication System
...Show More Authors

The work in this paper focuses on the system quality of direct and coherent communication system for two computers. A system quality is represented by Signal to Noise ratio (SNR) and Bit Error Rate (BER). First part of the work includes implementation of direct optical fiber communication system and measure the system quality .The second part of the work include implementation both the( homodyne and heterodyne)coherent optical fiber communication system and measure the system quality . Laser diode 1310 nm wavelength with its drive circuit used in the transmitter circuit . A single mode of 62.11 km optical fiber is selected as transmission medium . A PIN photo detector is used in the receiver circuit. The optical D-coupler was used to combine the optical signal that come from transmitter laser source with optical signal of laser local oscillator at 1310/1550 nm to obtain coherent detection . Results show that for direct detection the SNR and the BER (28.5 dB, 9.64x10-8,) respectively, while for homodyne and heterodyne coherent detection , the SNR(94.36,97.71)dB and the BER are (1.32x10-22,2.43x10-23) at maximum optical fiber length at 62.11 km. Results show that the homodyne and heterodyne detection are better than direct detection because the large output SNR and low BER of the received signal.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Nov 20 2012
Journal Name
J. Of University Of Anbar For Pure Science
Laser Processing For Nanoscale Size Quantum Wires of AlGaAs/GaAs
...Show More Authors

In this work we investigate and calculate theoretically the variation in a number of optoelectronic properties of AlGaAs/GaAs quantum wire laser, with emphasis on the effect of wire radius on the confinement factor, density of states and gain factor have been calculated. It is found that there exist a critical wire radius (rc) under which the confinement of carriers are very weak. Whereas, above rc the confinement factor and hence the gain increase with increasing the wire radius.

Publication Date
Fri Mar 01 2019
Journal Name
Iraqi Journal Of Physics
Spectroscopic investigation of Rhodamine-B thin film prepared by PLD technique
...Show More Authors

Optical properties of Rhodamine-B thin film prepared by PLD
technique have been investigated. The absorption spectra using
1064nm and 532 nm laser wavelength of different laser pulse
energies shows that all the curves contain two bands, B band and Q
bands with two branches, Q1 and Q2 band and a small shift in the
peaks location toward the long wavelength with increasing laser
energy. FTIR patterns for Rhodamine-B powder and thin film within
shows that the identified peaks were located in the standard values
that done in the previous researches. X-ray diffraction patterns of
powder and prepared Rhodamine-B thin film was display that the
powder has polycrystalline of tetragonal structure, while the thin film

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Apr 30 2023
Journal Name
Al-kindy College Medical Journal
The Surgical outcomes of fundus-first technique in lowering the rate of bile duct injuries and bleeding during open cholecystectomy that facing intraoperative difficulties: A single-center prospective study: The surgical outcomes of open fundus-first cholecystectomy technique.
...Show More Authors

Background: The problem of difficult gallbladder is not clearly defined and associated with real missing of therapeutic approaches that decreased morbidity. Moreover, the difficult gallbladder was reported as a contributing risk factor for biliary injury due to raised difficulty in surgical dissection within Calot’s triangle. The aim of this study is to determine the surgical outcomes of the open fundus-first cholecystectomy in lowering the rate of lethal intraoperative risks.

Subjects and Methods: Our prospective study conducted during the period of January 2019 to December 2022 at Ibn Sina specialized hospital, Khartoum, Sudan, for two hundred and fifty-three patients underw

... Show More
View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Wed Jun 01 2022
Journal Name
Journal Of The College Of Languages (jcl)
A study of the nomenclature of Russian vocabulary of Arabic origin denoting some religious worship, or denoting some political and social positions: «Лексика арабского происхождения со значением «служители религиозного культа, социального статуса» и её функционирование в русской речи»
...Show More Authors

      The present paper discusses one of the most important Russian linguistic features of Arabic origin Russian lexes denoting some religious worship or some political and social positions like Qadi, Wally, Sultan, Alam, Ruler, Caliph, Amir, Fakih, Mufti, Sharif, Ayatollah, Sheikh.. etc.  A lexical analysis of the two of the most efficient and most used words of Arabic origin Russian lexes that are “Caliph and Sheikh” is considered in the present study. The lexicographic analysis of these words makes it possible to identify controversial issues related to their etymology and semantic development.

The study is conducted by the use of the modern Russian and Arabic dictionary, specifically, (Intermediate lexicon Dictionary

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
The partial substitution of copper with nickel oxide on the Structural and electrical properties of HgBa<sub>2</sub> Ca<sub>2</sub> Cu<sub>3x</sub>Ni<sub>x</sub> O<sub>8+δ</sub> superconducting compound
...Show More Authors

View Publication
Scopus (31)
Crossref (15)
Scopus Clarivate Crossref
Publication Date
Tue Apr 18 2023
Journal Name
Al–bahith Al–a'alami
Media policy and its impact on the level of objectivity in the Iraqi media : A study from the communicators’ point of view in the Iraqi medi outlets for the period from (1/5/2021 to 1/9/2021)
...Show More Authors

The research aims to reveal the impact of media policy in Iraqi media outlets on the level of objectivity in these outlets. A study from the communicators’ point of view where the researcher used a survey method on the communicators in media outlets to reveal the extent of media policies knowledge as well as the pressures exerted by this policy on communicators in media outlets. It also reveals the extent of their commitment to objectivity, neutrality in dealing with information and the way used to transfer it.
The research sample included (179) respondents from communicators in a range of Media outlets such as (Press, Radio, and Television), The researcher was careful with the diversity of the sample, and

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
The effect of the Doping with Cobalt Transition Metal on the Dielectric and Structural Properties of Fe<sub>0.5</sub>Co<sub>x</sub>Mg<sub>0.95-x</sub>O Nanoparticles Synthesized by Sol-Gel Assisted Auto-Combustion
...Show More Authors
Abstract<p>The compound Fe<sub>0.5</sub>Co<sub>x</sub>Mg<sub>0.95-x</sub>O where (x= 0.025, 0.05, 0.075, 0.1) was prepared via the sol-gel technique. The crystalline nature of magnesium oxide was studied by X-ray powder diffraction (XRD) analysis, and the size of the sample crystals, ranging between (16.91-19.62nm), increased, while the lattice constant within the band (0.5337-0.4738 nm) decreased with increasing the cobalt concentration. The morphology of the specimens was studied by scanning electron microscopy (SEM) which shows images forming spherical granules in addition to the presence of interconnected chips. The presence of the elements involved in the super</p> ... Show More
View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Wed Sep 01 2021
Journal Name
Baghdad Science Journal
A Posteriori L_∞ (L_2 )+L_2 (H^1 )–Error Bounds in Discontinuous Galerkin Methods For Semidiscrete Semilinear Parabolic Interface Problems
...Show More Authors

The aim of this paper is to derive a posteriori error estimates for semilinear parabolic interface problems. More specifically, optimal order a posteriori error analysis in the - norm for semidiscrete semilinear parabolic interface problems is derived by using elliptic reconstruction technique introduced by Makridakis and Nochetto in (2003). A key idea for this technique is the use of error estimators derived for elliptic interface problems to obtain parabolic estimators that are of optimal order in space and time.

View Publication Preview PDF
Scopus (12)
Crossref (9)
Scopus Clarivate Crossref
Publication Date
Tue Dec 01 2020
Journal Name
Iraqi Journal Of Physics
Modifications to Accelerate the Iterative Algorithm for the Single Diode Model of PV Model
...Show More Authors

This paper discussed the solution of an equivalent circuit of solar cell, where a single diode model is presented. The nonlinear equation of this model has suggested and analyzed an iterative algorithm, which work well for this equation with a suitable initial value for the iterative. The convergence of the proposed method is discussed. It is established that the algorithm has convergence of order six. The proposed algorithm is achieved with a various values of load resistance. Equation by means of equivalent circuit of a solar cell so all the determinations is achieved using Matlab in ambient temperature. The obtained results of this new method are given and the absolute errors is demonstrated.

View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Measuring the Implementation gap of Operational requirement according to the international standard (ISO 9001:2015) in the National Insurance Company : Applied research.
...Show More Authors

The aim of the research is to diagnose and analyze the gap between the actual reality and the application of the eighth requirement (operation) in the National Insurance Company in accordance with the international standard specification for the quality management system (ISO 9001:2015), which is related to the planning, implementation and control of operations, which would raise the level of performance of employees and be reflected in the provision of An appropriate service for the faithful, as the reality of the condition of the requirement was studied by identifying the strengths and weaknesses of the system to diagnose the gap and find ways to address it. A workshop was held with company officials, through which questions were raise

... Show More
View Publication Preview PDF