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IMPROVEMENT OF MARSHALL PROPERTIES FOR HOT MIX ASPHALT BY USING CERAMIC FIBER
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Publication Date
Sat Jun 01 2013
Journal Name
Nahrain University, College Of Engineering Journal
Planned Reliability Improvement Calculation of Iraqi Super Grid Applying Fuzzy Logic Method
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Reliability is an essential measure and important component of all power system planning and operation procedures. It is one of the key design factors when designing complex, critical and expensive systems. This paper presents a fuzzy logic approach for reliability improvement planning purposes. Evaluating the reliability of the complex and large planned Iraqi super grid ;as Al- Khairat generating station with its tie set is intended to be compact to that grid; and determination of the given reliability improvement project are the major goals of the paper. Results show that the Iraqi super grid reliability is improved by 9.64%. In the proposed technique, fuzzy set theory is used to include imprecise indices of different components in normal

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Publication Date
Thu Oct 01 2015
Journal Name
International Journal Of Engineering Sciences & Research Technology
IMPROVEMENT THE MECHANICAL WEAR RESISTANCE OF METAL KNIFE USED IN HARVESTER MACHINE
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SKF Dr. Abbas S. Alwan, Dhurgham I. Khudher, INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY, 2015

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Publication Date
Thu Dec 01 2022
Journal Name
Al-khwarizmi Engineering Journal
BER Performance Improvement of Dual Chaotic Maps Based on STBC Communication System
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Sensitive information of any multimedia must be encrypted before transmission. The dual chaotic algorithm is a good option to encrypt sensitive information by using different parameters and different initial conditions for two chaotic maps. A dual chaotic framework creates a complex chaotic trajectory to prevent the illegal use of information from eavesdroppers. Limited precisions of a single chaotic map cause a degradation in the dynamical behavior of the communication system. To overcome this degradation issue in, a novel form of dual chaos map algorithm is analyzed. To maintain the stability of the dynamical system, the Lyapunov Exponent (LE) is determined for the single and dual maps. In this paper, the LE of the single and dual maps

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Publication Date
Mon Dec 01 2008
Journal Name
Iraqi Journal Of Physics,2008
optical pulse propagation in photonic bandgap fiber Bragg grating
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Abstract: In this work we demonstrate and investigate the optical pulse propagation in a photonic band gap fiber Bragg grating (FBG). The light propagates in opposite direction in FBG is explained and discussed by a Coupled Mode Theory (CMT). The photonic band gap (stop band gap) is created by fabricated, a Bragg grating in optical fiber. The results show the pulse spectrum falls entirely within the stop band gap, the entire pulse is reflected by the grating, while when the pulse spectrum is outside the stop band gap the pulses will transmitted through the grating. The group velocity (VG) becomes zero at the edges of the stop band and group velocity dispersion β2 is anomalous on the shorter side of stop band gap whereas β2 for uniform fi

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Publication Date
Fri Feb 08 2019
Journal Name
Iraqi Journal Of Laser
Refractive Index Scaling in Hollow Core Photonic Crystal Fiber
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In this paper, simulation study of the frequency shift of photonic bandgaps due to refractive index scaling using liquids filled hollow-core photonic crystal fibers is presented. Different liquids (distilled water, n-hexane, methanol, ethanol and acetone) are used to fill the cladding of 2 types of hollow core photonic crystal fibers (HC19-1060, HC7-1060). These liquids are used to change the effective index scaling and index contrast of the cladding. The effect of increasing temperature of the liquid (20-100 0C for water and 20-70 0C for other liquids ) infiltrated hollow core fiber on the bandgap width and transmission properties has been computed. The maximum photonic bandgap width at 0.0243 has appeared with filling HC7-1060 PCF with

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Publication Date
Tue Sep 11 2018
Journal Name
Iraqi Journal Of Physics
The effects of silica addition on the structural, electrical and mechanical characteristics of MgAl2O4 spinel ceramic phase
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The ceramic compound Mg1-xSixAl2O4 (x= 0, 0.1, 0.2, 0.3, 0.4) was prepared from nano powder of Al2O3 and MgO doped with Nano powder of SiO2 at different molar ratios. The specimens were prepared by standard chemical solid reaction technique and sintered at 1450 oC. Structure of the specimens was analyzed by using X-ray diffraction (XRD). The X-ray patterns of the specimens showed the formation of pure simple cubic spinel structure MgAl2O4 phase with space group of ̅ . The average grain size and surface topology were studied by atomic force microscopy. The results showed that the average grain size was about 73-90 nm. The DC electrical properties of the specimen were measured. The apparent density was found to increase and the porosity a

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Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Laser
Enhanced Relative Humidity Sensor via Diameter of No-Core Fiber Structure
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Single mode-no core-single mode fiber structure with a section of tuned no-core fiber diameter to sense changes in relative humidity has been experimentally demonstrated. The sensor performance with tuned NCF diameter was investigated to maximize the evanescent fields. Different tuned diameters of of (100, 80, and 60)μm were obtained by chemical etching process based on hydrofluoric acid immersion. The highest wavelength sensitivity was obtained 184.57 pm/RH% in the RH range of 30% –100% when the no-core fiber diameter diameter was 60 μm and the sensor response was in real-time measurements

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Publication Date
Sat Mar 01 2008
Journal Name
Iraqi Journal Of Physics
Mathematical Model of Amplified Stimulated Raman Scattering and Fiber Raman Amplifier
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The result of a developed mathematical model for predicting the design
parameters of the fiber Raman amplifier (FRA) are demonstrated. The amplification
parameters are tested at different pump power with different fiber length. Recently,
the FRA employed in optical communication system to increase the repeater distance
as will as the capacity of the communication systems. The output results show, that
high Raman gain can be achieved by high pumping power, long effective area that
need to be small for high Raman gain. High-stimulated Raman gain coefficient is
recommended for high Raman amplifier gain, the low attenuation of the pump and the
transmitted signal in the fiber lead to high Raman gain.

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Publication Date
Tue Mar 31 2015
Journal Name
Al-khwarizmi Engineering Journal
Dual Measurements of Pressure and Temperature With Fiber Bragg Grating Sensor
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Abstract

The fiber Bragg grating (FBG) technology has been rapidly applied in the sensing technology field. In this work, uniform FBG was used as pressure sensor based on measuring related Bragg wavelength shift. The pressure was applied directly by air compressor to the sensor and the pressure was ranged from 1 to 6 bar.

      This sensor also was affected by the external temperature so as a result it could be used as a temperature sensor. This sensor could be used to monitor the pressure of dams. It has been shown from the result that the sensor is very sensitive to the pressure and the sensitivity was (67 pm\bar) and is very sensitive to temperature and the sensitivity was (10p

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Compressive Behavior of Fiber Reinforced Concrete Columns Rehabilitated with CFRP Warps
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Over the last few years, there has been a worldwide increase in the use of composite materials for rehabilitation of deficient reinforced concrete structures. One important application of this technology is the use of Carbon Fiber Reinforced Polymer (CFRP) jacket to provide external confinement of reinforced concrete columns. Square concrete column specimens 100×100×1000 mm with concrete
compressive strength of about 30 and 50 MPa, steel fiber volume fraction 0%, 0.5%, 0.75%, and percentage of longitudinal reinforcement 2.01%, 3.14% and 4.52% were tested until failure in previous research. In this research seven tested columns were repaired and rehabilitated using one layer of CFRP flexible wraps and tested to determine their ultim

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