Preferred Language
Articles
/
ijp-113
Study of optical bistability in a fully optimized laser Fabry-Perot system
...Show More Authors

The analytical study of optical bistability is concerned in a fully
optimized laser Fabry-Perot system. The related phenomena of
switching dynamics and optimization procedure are also included.
From the steady state of optical bistability equation can plot the
incident intensity versus the round trip phase shift (φ) for different
values of dark mistuning 




12
,
6
,
3
,
1.5
0 , o
   
 or finesse (F= 1, 5, 20,
100). In order to obtain different optical bistable loops. The inputoutput
characteristic for a nonlinear Fabry-Perot etalon of a different
values of finesse (F) and using different initial detuning (φ0) are used
in this research. When the cavity finesse values increase, the switch-
ON intensity increases for the same value of (φ0), because the
bistable loop width increases with increasing the cavity finesse
values.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Dec 15 2022
Journal Name
Arab World English Journal
Investigating Teachers of English Knowledge and Awareness of Dyslexia: A case study in Primary Iraqi Schools
...Show More Authors

Dyslexia is a learning disability in which people face difficulty reading though they are intelligent and have motivation for reading. Therefore; it impacts the portion of the brain responsible for processing language. Such a condition compromises the learning efficiency of the affected person, which generally gets unnoticed. Even affected children are unaware of their state. The study investigates the knowledge and awareness of dyslexia among teachers of English in Iraqi primary schools. this study has three objectives: (i) To investigate the amount of awareness and knowledge among the primary school teachers of English in Baghdad City about dyslexia.; (ii) To examine how English teachers’ awareness of dyslexia is affected by the

... Show More
View Publication
Scopus (2)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Fri Nov 03 2023
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
The Effectiveness of Autogenous Dentin Graft as a Biomaterial in Optimizing the Esthetic Outcomes of Immediate Dental Implants: A Prospective Clinical Study
...Show More Authors

Background: Immediate implant placement in the maxillary anterior region was challenging, especially with the jumping gap and limited primary implant stability. Objective: To assess the autogenous dentin graft biomaterial's ability to improve the esthetic outcomes of an immediately inserted implant. Methods: Twenty patients with non-restorable retained roots in the maxillary non-molar region surrounded by natural sound teeth were included in this study after a complete clinical and radiological examination, including patient health and clinical fitness for the immediate dental implant procedure. A single dental implant was inserted for each patient, and the resulting jump distance was filled with the mineralized dentin graft and co

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (2)
Scopus Crossref
Publication Date
Mon Sep 30 2019
Journal Name
College Of Islamic Sciences
What Bukhari shortened to a bug in its attribution: (Applied study in the correct mosque)
...Show More Authors

This study aims to show some of Imam Al-Bukhari's criticism of the Hadith from the Metn side, and part of his methodology in dealing with the correct hadiths that are tainted by a bug. This research focuses on what Imam Al-Bukhari summarized in his Sahih illusion of the narrator in his attribution, or uniqueness of the narrator, or to suggest a novel. We find that Bukhari sometimes abbreviates the hadeeth, and does not bring it out completely in his Sahih. He is satisfied with the abbreviated position but has done so because of a bug in it. The Bukhari usually does not declare his intention but knows this through tracking, inspection, and research of the correct hadiths.

View Publication Preview PDF
Publication Date
Tue Sep 01 2020
Journal Name
Journal Of Engineering
Experimental Study on Heat Transfer and Flow Characteristics in Subcooled Flow Boiling in a Microchannel
...Show More Authors

The current study presents an experimental investigation of heat transfer and flow characteristic for subcooled flow boiling of deionized water in the microchannel heat sink. The test section consisted of a single microchannel having 300μm wide nominal dimensions and 300μm height (hydraulic diameter of 300μm). The test section formed of oxygen-free copper with 72mm length and 12mm width. Experimental operation conditions spanned the heat flux (78-800) kW/m2, mass flux (1700 and 2100) kg/m2.s at 31˚C subcooled inlet temperature. The boiling heat transfer coefficient is measured and compared with existing correlations. Also, the experimental pressure drop is measured and compared with microscale p

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Jun 29 2018
Journal Name
Journal Of The College Of Education For Women
HandWritten Numerals Recognition System
...Show More Authors

  Recognition is one of the basic characteristics of human brain, and also for the living   creatures. It is possible to recognize images, persons, or patterns according to their characteristics. This recognition could be done using eyes or dedicated proposed methods. There are numerous applications for pattern recognition such as recognition of printed or handwritten letters, for example reading post addresses automatically and reading documents or check reading in bank.

      One of the challenges which faces researchers in character recognition field is the recognition of digits, which are written by hand. This paper describes a classification method for on-line handwrit

... Show More
View Publication Preview PDF
Publication Date
Wed Jan 01 2014
Journal Name
Journal Of The College Of Basic Education
Effect of annealing temperature on Structural and Optical properties of amorphous Selenium thin films
...Show More Authors

Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Studying of the optical properties of poly (vinyl alcohol) films using Aluminum sulphate as additive by measuring allowed direct transition energy gap
...Show More Authors

The change in the optical band gap and optical activation energy have been investigated for pure Poly (vinyl alcohol)and Poly (vinyl alcohol) doped with Aluminum sulphate to proper films from their optical absorption spectra. The absorption spectra were measured in the wave range from (200-700) nm at temperature range (25-140) 0C. The optical band gap (Eg) for allowed direct transition decrease with increase the concentration of Aluminum sulphate. The optical activation energy for allowed direct transition band gap was evaluated using Urbach- edges method. It was found that ?E increases with increasing the concentration of Al2 (SO4)3 and decreases when temperature increases.

View Publication Preview PDF
Crossref
Publication Date
Wed Jun 10 2009
Journal Name
Iraqi Journal Of Laser
Real Time Quantum Bit Error Rate Performance Test for a Quantum Cryptography System Based on BB84 protocol
...Show More Authors

In this work, the performance of the receiver in a quantum cryptography system based on BB84 protocol is scaled by calculating the Quantum Bit Error Rate (QBER) of the receiver. To apply this performance test, an optical setup was arranged and a circuit was designed and implemented to calculate the QBER. This electronic circuit is used to calculate the number of counts per second generated by the avalanche photodiodes set in the receiver. The calculated counts per second are used to calculate the QBER for the receiver that gives an indication for the performance of the receiver. Minimum QBER, 6%, was obtained with avalanche photodiode excess voltage equals to 2V and laser diode power of 3.16 nW at avalanche photodiode temperature of -10

... Show More
View Publication Preview PDF
Publication Date
Wed Apr 14 2021
Journal Name
Wireless Personal Communications
A Partial CSI Estimation Approach for Downlink FDD massive-MIMO System with Different Base Transceiver Station Topologies
...Show More Authors

Massive multiple-input multiple-output (massive-MIMO) is a promising technology for next generation wireless communications systems due to its capability to increase the data rate and meet the enormous ongoing data traffic explosion. However, in non-reciprocal channels, such as those encountered in frequency division duplex (FDD) systems, channel state information (CSI) estimation using downlink (DL) training sequence is to date very challenging issue, especially when the channel exhibits a shorter coherence time. In particular, the availability of sufficiently accurate CSI at the base transceiver station (BTS) allows an efficient precoding design in the DL transmission to be achieved, and thus, reliable communication systems can be obtaine

... Show More
View Publication
Scopus (6)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Sun Dec 01 2024
Journal Name
Energy Storage
Comprehensive Study of <scp>PAN</scp>‐<scp>NaBF<sub>4</sub></scp> Solid Polymer Electrolytes: Insights Into Optical, Structural, Thermal, Electrical, and Electrochemical Properties for Sodium‐Ion Batteries
...Show More Authors
ABSTRACT<p>This research explores the use of solid polymer electrolytes (SPEs) as a conductive medium for sodium ions in sodium‐ion batteries, presenting a possible alternative to traditional lithium‐ion battery technology. The researchers prepare SPEs with varying molecular weight ratios of polyacrylonitrile (PAN) and sodium tetrafluoroborate (NaBF<sub>4</sub>) using a solution casting method with dimethyl formamide as the solvent. Through optical absorbance measurements, we identified the PAN:NaBF<sub>4</sub> (80:20) SPE composition as having the lowest energy band gap value (4.48 eV). This composition also exhibits high thermal stability based on thermogravimetric analysis results. </p> ... Show More
View Publication
Scopus (6)
Crossref (6)
Scopus Clarivate Crossref