Preferred Language
Articles
/
alkej-389
Transient Behavior Analysis for Solar Energy Storage in PCM-CFM Material Using Equivalent Heat Capacity Method as Storage Model
...Show More Authors

A paraffin wax and copper foam matrix were used as a thermal energy storage material in the double passes air solar chimney (SC) collector to get ventilation effect through daytime and after sunset. Air SC collector was installed in the south wall of an insulated test room and tested with different working angles (30o, 45o and 60o). Different SC types were used; single pass, double passes flat plate collector and double pass thermal energy storage box collector (TESB). A computational model based on the finite volume method for transient tw dimensional domains was carried out to describe the heat transfer and storage in the thermal energy storage material of collector. Also, equivalent specific heat method was employed to describe the heat storage and release in the mushy zone. Experimental results referred to an increase in thermal conductivity of paraffin wax that supported by copper foam matrix more than ten times. While the ventilation effect was still active for hours after the sun set, depending on the heat storage amount. Maximum ventilation mass flow rate with TESB collector was recorded with value equals to 36.651 kg/hr., when the overall discharge coefficient that was calculated for the system equals to 0.371. Experimental results showed that the best working angle range was 45~60o, and the highest air to the collector approaching temperature appeared to the double passes flat plate collector. Results gave greater heat storage efficiency of (47)% when the maximum solar radiation was 780 W/m2 at 12.00pm, while the energy summation through duration charge time was 18460 kJ. Computational results, depending on the equivalent heat capacity method for heat storage or release from phase change material that supported by copper foam matrix, showed the behavior of paraffin wax melting and solidification situation through periodic for charge and released heat from the solar collector. Also, these results gave agreement approaching the experimental results for the heat storage in the combined heat storage material, with standard error of 16.8%.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Jan 11 2024
Journal Name
Eximia
Using an educational method according to special exercises to perform the skill of bow and develop flexibility for cub wrestlers in Iraq
...Show More Authors

creating unique exercises utilizing a teaching approach that works with the research sample, determining how special exercises affect the development of torso flexibility, and determining how special exercises affect the development of bow ability. Activate the search The results of the pre- and post-tests for the control and experimental research groups show a statistically significant association that is favoring the post-test in the development of bow skill performance Using the experimental technique, the researcher set up one group and gave them two tests (pre and post) based on scientific theories that made sense for the topic at hand. Forty adolescent wrestlers from the Adhamiya Club in the Baghdad Governorate were recognized

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Jul 01 2023
Journal Name
Journal Of Analytical Chemistry
A Spectrophotometric Method for Tetracycline Determination in its Bulk Powder and Pharmaceutical Formulations Using Flow Injection and Batch Procedures: a Comparative Study
...Show More Authors

A reliable and environmental analytical method was developed for the direct determination of tetracycline using flow injection analysis (FIA) and batch procedures with spectrophotometric detection. The developed method is based on the reaction between a chromogenic reagent (vanadium (III) solution) and tetracycline at room temperature and in a neutral medium, resulting in the formation of an intense brown product that shows maximum absorption at 395 nm. The analytical conditions were improved by the application of experimental design. The proposed method was successfully used to analyze samples of commercial medications and verified throughout the concentration ranges of 25–250 and 3–25 µg/mL for both FIA and batch procedures, respecti

... Show More
View Publication
Scopus (8)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Mon Jan 02 2017
Journal Name
Al-academy
How to build a virtual personal imagined in the picture, directed by James Cameron (Avatar) movie as a model
...Show More Authors

The personal drama in particular, and one of the key elements underlying the dramatic structure to convey ideas and visions presented by the author when writing the text of the dramatic fall after that on the way out the submission form that suits the proposals of the text and processors directorial would push the wheel of dramatic structure to the front. So take the maker of the artwork (writer) undertook the transfer of those events and personalities in art presumed sometimes real and sometimes, in order to enrich the art inspired by the human reality through the ages, and full of its themes and ideas that led to the development experiences of peoples experiences of living. Therefore, we find it important to research in the characters

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Theoretical Calculation of the Electron Transport Parameters and Energy Distribution Function for CF3I with noble gases mixtures using Monte Carlo simulation program
...Show More Authors

View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Sun Jun 12 2016
Journal Name
Baghdad Science Journal
Measurement of Photon Buildup Factor for Samples of Iraqi Carbon Black Material
...Show More Authors

The buildup factor was measured after irradiating Iraq carbon black powder using each of and sources respectively, using mixing ratios 40% & 50% for thickness range . The results showed that the buildup factor depends on energy and has limited dependence on the mixing ratio. The QIFT program succeeded accenting for the experimental results even for expected values more than 4 m.f.p outside the thickness range.

View Publication Preview PDF
Crossref
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
...Show More Authors

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

... Show More
View Publication Preview PDF
Publication Date
Mon Jul 15 2019
Journal Name
Iet Microwaves, Antennas & Propagation
Hilbert metamaterial printed antenna based on organic substrates for energy harvesting
...Show More Authors

Abstract In this study, an investigation is conducted to realise the possibility of organic materials use in radio frequency (RF) electronics for RF-energy harvesting. Iraqi palm tree remnants mixed with nickel oxide nanoparticles hosted in polyethylene, INP substrates, is proposed for this study. Moreover, a metamaterial (MTM) antenna is printed on the created INP substrate of 0.8 mm thickness using silver nanoparticles conductive ink. The fabricated antenna performances are instigated numerically than validated experimentally in terms of S11 spectra and radiation patterns. It is found that the proposed antenna shows an ultra-wide band matching bandwidth to cover the frequencies from 2.4 to 10 GHz with bore-sight gain variation from 2.2 to

... Show More
View Publication
Scopus (55)
Crossref (35)
Scopus Clarivate Crossref
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Improve the performance of solar cells using new designs for pelvic center wheel Type V compound mirrors encased by Vernil glasses
...Show More Authors

Design and build a center basins new p-type four mirrors were studied its effect on all parameters evaluating the performance of the solar cell silicon in the absence of a cooling system is switched on and noted that the efficiency of the performance Hzzh cell increased from 11.94 to 21 without cooling either with cooling has increased the efficiency of the

View Publication Preview PDF
Publication Date
Fri Dec 01 2023
Journal Name
Baghdad Science Journal
Building a Statistical Model to Detect Foreground Objects and using it in Video Steganography
...Show More Authors

Video steganography has become a popular option for protecting secret data from hacking attempts and common attacks on the internet. However, when the whole video frame(s) are used to embed secret data, this may lead to visual distortion. This work is an attempt to hide sensitive secret image inside the moving objects in a video based on separating the object from the background of the frame, selecting and arranging them according to object's size for embedding secret image. The XOR technique is used with reverse bits between the secret image bits and the detected moving object bits for embedding. The proposed method provides more security and imperceptibility as the moving objects are used for embedding, so it is difficult to notice the

... Show More
View Publication Preview PDF
Crossref (1)
Scopus Crossref
Publication Date
Wed Sep 15 2021
Journal Name
Al-academy
representations of body language in the contemporary Iraqi theatrical show "Imagine That as a model": عمار عبد سلمان محمد
...Show More Authors

There is no doubt that each of the arts has a material from which the aesthetic achievement is built, so the researcher found that the art of theater, especially the show, whose artistic achievement is based on the body of the actor who emits the formal language (body language), is the focus of interest and active presence, because the body possesses its spiritual qualities that made him and the ability to The formation of things by (his body language), so the researcher studied this theatrical phenomenon and divided it into four chapters. In the first chapter, the research problem included the following question: (Is there a phenomenon of body language in the contemporary theatrical show "Imagine that" as a model) so It is of cognitive

... Show More
View Publication Preview PDF
Crossref