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Yearly Energy, Exergy, and Environmental (3E) Analyses of A Photovoltaic Thermal Module and Solar Thermal Collector in Series
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The annual performance of a hybrid system of a flat plate photovoltaic thermal system and a solar thermal collector (PVT/ST) is numerically analyzed from the energy, exergy, and environmental (CO2 reduction) viewpoints. This system can produce electricity and thermal power simultaneously, with higher thermal power and exergy compared to conventional photovoltaic thermal systems. For this purpose, a 3D transient numerical model is developed for investigating the system's performance in four main steps: (1) investigating the effects of the mass flow rate of the working fluid (20 to 50 kg/h) on the temperature behavior and thermodynamic performance of the system, (2) studying the impacts of using glass covers on the different parts of the system, (3) evaluating the annual energy and exergy analyses of the system under Mashhad weather conditions, and (4) examining the CO2 reduction by using the proposed system. The results show that for the (glazed) PVT and (glazed) ST systems, increasing the mass flow rate of the working fluid from 20 to 50 kg/h results in 22% and 1.5% improvements in both thermal and electrical power, respectively. However, the thermal exergy of the system decreases by 40.1%. Furthermore, the (glazed) PVT/(glazed) ST systems generate approximately 86% and 264% more thermal power and energy than the PVT/ST systems, respectively. Using a (glazed) PVT/(glazed) ST system with a working fluid’s mass flow rate of 50 kg/h results in maximum thermal and electrical efficiencies of 40.7% and 16.22%, respectively. According to the annual analysis, the highest average thermal and electrical power, equal to approximately 338.3 and 24 W, respectively, is produced in August. The amount of CO2 reduction increases by increasing the mass flow rate and using a glass cover. The PVT/(glazed)ST system has the potential to reduce CO2 emissions by 426.3 kg per year. 

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Publication Date
Wed Feb 20 2019
Journal Name
Iraqi Journal Of Physics
The solar eclipse and its relation with higree months
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The solar eclipse occurs at short time before the crescent birth moment when the moon near any one of moon orbit nodes It is important to determine the synchronic month which is used to find Higree date. The 'rules' of eclipses are: 

Y= ± 0.997  of Earth radius , the solar eclipse is central and 0.997 < |Y| < 1.026 the umbra cone touch the surface of the Earth, where Y is the least distance from the axis of the moon's shadow to the center of the Earth in units of the equatorial radius of the Earth.

A new model have been designed, depend on the horizontal coordinates of the sun, moon, the distances Earth-Moon (rm), Earth-sun (rs) and |Y| to determine the date and times of total solar eclipse and the geogra

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Publication Date
Sat Dec 01 2018
Journal Name
2018 Third Scientific Conference Of Electrical Engineering (scee)
A UWB Monopole Antenna Design based RF Energy Harvesting Technology
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Recently, wireless charging based RF harvesting has interfered our lives [1] significantly through the different applications including biomedical, military, IoT, RF energy harvesting, IT-care, and RFID technologies. Wirelessly powered low energy devices become significantly essential for a wide spectrum of sensing applications [1]. Such devices require for low energy resources from sunlight, mechanical vibration, thermal gradients, convection flows or other forms of harvestable energy [2]. One of the emerging power extraction resources based on passive devices is harvesting radio frequency (RF) signals powers [3]–[5]. Such applications need devices that can be organized in very large numbers, so, making separate node battery impractical.

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Publication Date
Wed Jan 01 2025
Journal Name
Journal Of Advanced Transportation
Resilience and Environmental Performance of SMEs: The Mediating Role of Ambidextrous Green Innovation
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The disruptions in supply chains have put small‐ and medium‐sized enterprises (SMEs) in dire need of resilient supply chains through which they can improve their performance. Based on the resource dependence theory, this study proposes a mediation model to improve the environmental performance (EP) of SMEs. The purpose of this study is to investigate the effect of supply chain resilience (SCR) on EP mediated by ambidextrous green innovation (AMGI). We proved a structural equation model based on questionnaire data from 261 companies in Iraq to test our hypotheses. The results show that SCR has a positive effect on AMGI for proactive and exploitative green innovation dimensions and positive impact on SMEs’ EP. AMGI plays a media

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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Identification and Purification of Cholera Like Toxin from Environmental Isolate of Vibrio cholerae
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The presence and prevalence of V. cholerae were investigated in forty five water samples collected from different locations of Tiger River/ Baghdad city. Twenty one isolates were isolated by adopting a simple isolation techniques. The final identification revealed that only three isolates were confirmed as V. cholerae. They were named 1J, 1R and Dial 131 which are all serogrouped as non-O1. Toxin Coregulated Pili (TCP) and heat labile enterotoxin (LT) were determined in only the environmental isolate 1J while non of the isolates produced heat stabile toxin (ST). The purification scheme was improved, few steps were adopted to include back extraction of ammonium sulfate, saturation between 80-20%, desalting through Sephadex G25, and gel filt

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Publication Date
Tue Nov 05 2019
Journal Name
Humanities &amp; Social Sciences Reviews
HUMAN LAB RATS IN JAMES DASHNER’S THE MAZE RUNNER SERIES (2009 – 2011): HISTORICAL REFERENCES, PRESENT ALLUSIONS, AND DYSTOPIAN FUTURE
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Purpose: This study aims to shed the light on allusions to real lab rats in Dashner’s trilogy: The Maze Runner (2009), The Scorch Trails (2010), and The Death Cure (2011).  It also aims to trace the historical documents and chronicles essential to reveal the justifications behind the vague political and scientific crimes.  Methodology: The researchers have used the literary analytical approach to study and analyze selected prominent aspects from each novel; such as the concept of lab rats and genocide crimes in The Maze Runner; references to weather experiments, the climate change conspiracy, gas chambers, and the Holocaust in The Scorch Trails; and finally, the man-made diseases and biological weapons in The Death Cure. Results

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Publication Date
Tue Nov 05 2019
Journal Name
Humanities &amp; Social Sciences Reviews
HUMAN LAB RATS IN JAMES DASHNER’S THE MAZE RUNNER SERIES (2009 – 2011): HISTORICAL REFERENCES, PRESENT ALLUSIONS, AND DYSTOPIAN FUTURE
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Purpose: This study aims to shed the light on allusions to real lab rats in Dashner’s trilogy: The Maze Runner (2009), The Scorch Trails (2010), and The Death Cure (2011).  It also aims to trace the historical documents and chronicles essential to reveal the justifications behind the vague political and scientific crimes.  Methodology: The researchers have used the literary analytical approach to study and analyze selected prominent aspects from each novel; such as the concept of lab rats and genocide crimes in The Maze Runner; references to weather experiments, the climate change conspiracy, gas chambers, and the Holocaust in The Scorch Trails; and finally, the man-made diseases and biological weapons in The Death Cure. Results

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Publication Date
Thu Dec 01 2016
Journal Name
International Journal Of Vlsi Design & Communication Systems (vlsics)
SIMULTANEOUS OPTIMIZATION OF STANDBY AND ACTIVE ENERGY FOR SUB THRESHOLD CIRCUITS
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Increased downscaling of CMOS circuits with respect to feature size and threshold voltage has a result of dramatically increasing in leakage current. So, leakage power reduction is an important design issue for active and standby modes as long as the technology scaling increased. In this paper, a simultaneous active and standby energy optimization methodology is proposed for 22 nm sub-threshold CMOS circuits. In the first phase, we investigate the dual threshold voltage design for active energy per cycle minimization. A slack based genetic algorithm is proposed to find the optimal reverse body bias assignment to set of noncritical paths gates to ensure low active energy per cycle with the maximum allowable frequency at the optimal supply vo

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Publication Date
Sun Mar 01 2020
Journal Name
Iraqi Journal Of Physics
Effect of Laser Energy and Repetition Rate on Holmium Plasma Emission
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The holmium plasma induced by a 1064-nmQ-switched Nd:YAG laser in air was investigated. This work was done theoretically and experimentally.  Cowan code was used to get the emission spectra for different transition of the holmium target. In the experimental work, the evolution of the plasma was studied by acquiring spectral images at different laser pulse energies (600,650,700, 750, and 800 mJ). The repetition rates of (1Hz and 10Hz) in the UV region (200-400 nm). The results indicate that, the emission line intensities increase with increasing of the laser pulse energy and repetition rate. The strongest emission spectra appeared when the laser pulse energy is 800mJ and 10 Hz repetition rate at λ= 345.64nm, with the maximum intensi

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Publication Date
Mon Feb 18 2019
Journal Name
Iraqi Journal Of Physics
Indium doped ZnO Urbach energy and dispersion parameters of thin films
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The characterization of ZnO and ZnO:In thin films were confirmed by spray pyrolysis technique. The films were deposited onto glass substrate at a temperature of 450°C. Optical absorption measurements were also studied by UV-VIS technique in the wavelength range 300-900 nm which was used to calculate the optical constants. The changes in dispersion and Urbach parameters were investigated as a function of In content. The optical energy gap was decreased and the wide band tails were increased in width from 616 to 844 eV as the In content increased from 0wt.% to 3wt.%. The single–oscillator parameters were determined also the change in dispersion was investigated before and after doping.

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Publication Date
Wed Jan 13 2016
Journal Name
University Of Baghdad
Employ Mathematical Model and Neural Networks for Determining Rate Environmental Contamination
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