Preferred Language
Articles
/
alkej-714
Impact of using Double Layers Perforated Liners on the Acoustic Treatments of the Combustor Systems
...Show More Authors

The response of the combustor’s liner to the air-flow that passes through it is the key reason for the combustion chambers noise, hence the instabilities of those chambers that decreases the mechanical efficiency of such sections, by increased its mechanical vibrations, which increases the failure rate created during originating of the cracks spreading by the shakes producing by the series of high-level frequencies. Accordingly, any work debating the impact of the context of liners in the combustion chamber can provide grasping for the combustion noise generated by the undesirable vibrations, and benefits the industrial firms to design an ideal production procedure which increases the lifespan of the combustor. The goal of this work is to examine the influence of the acoustic treatment using a double layers cylindrical perforated liner on the acoustic transmission loss of gas turbines. The liners layout influences on this acoustic parameter was examined using an experimental data gained by the insertion of a full scale single and double patterns of perforated liners into the unique large scale acoustic wind tunnel at the acoustic research center at Hull University. The experimental tests under-designed acoustic signals were established firstly using 0m/s air cross-flow velocity, then by changed velocities with interval 5m/s ranging between 10m/s to 25m/s. MATLAB script was used to simulate, analyze, and figure out the data collected the insertion of single and double layer patterns of the perforated liner. The experiments demonstrated that, if the perforation acoustic treatments are applied, the acoustic transmission loss will decrease, particularly obvious at higher level frequencies. Further, the results exposed that the air tunnel with the insertion of the liner with double layers reveals an improved perforation acoustic treatment.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Jun 20 2021
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
ON THE ECOLOGY AND SPECIES DIVERSITY OF THE FRESHWATER GASTROPODS OF SPRINGS IN ANDIJAN REGION, UZBEKISTAN
...Show More Authors

This study examines the species composition, biodiversity, zoogeography, and ecology of freshwater gastropods of 12 springs in Andijan region of Uzbekistan. The study used generally accepted malacological, faunistic, ecological, analytical, and statistical methods. As a result of research in the springs, 14 species of freshwater gastropods belonging to 2 subclasses, 5 families, and 10 genera were recorded. 7 of them are endemic to Central Asia. When indicators of biodiversity of mollusks were analyzed according to the Shannon index, it was found that the highest value was recorded in the springs besides the hills. According to the biotope of distribution and bioecological features, they were divided into cryophilic, phytophilic, pelophil

... Show More
View Publication Preview PDF
Scopus (10)
Crossref (1)
Scopus Crossref
Publication Date
Sun Jan 01 2023
Journal Name
Materials Today: Proceedings
The influence of water-gypsum ratio on the properties of national gypsum (Jοss) for various additives
...Show More Authors

View Publication
Scopus (15)
Crossref (9)
Scopus Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Al-khwarizmi Engineering Journal
A Review of the Stereo lithography 3D Printing Process and the Effect of Parameters on Quality
...Show More Authors

Stereo lithography (SLA) three-dimensional (3D) printing process is a type of additive manufacturing techniques that uses digital models from computer-aided design to automatically produce customized 3D objects. Around 30 years, it has been widely utilized in the manufacturing, design, engineering, industrial sectors and its applications in dentistry for manufacturing prosthodontics are very important. The stereo lithography technology is highly regarded because it can produce items with excellent precision especially when selecting the best process parameters. This review article offers a useful and scientific summary of SLA three-dimensional printing technology and its brief history. The specific type of 3D printers which is SLA t

... Show More
Scopus (28)
Crossref (26)
Scopus Crossref
Publication Date
Wed Aug 06 2025
Journal Name
Innovative Infrastructure Solutions
Understanding the effectiveness of elastomeric and plastomeric polymers on the high-temperature performance of asphalt binders
...Show More Authors

The global rise in temperature and the desert climatic conditions prevalent in Middle Eastern countries have exacerbated rutting distress in heavily trafficked highways. Conventional asphalt binders with a high-temperature performance grade (PG 70) have proven inadequate under such extreme conditions, necessitating the development of modified binders with enhanced high-temperature performance. While polymer modification using styrene-butadiene-styrene (SBS), an elastomeric polymer, and ethylene-vinyl acetate (EVA), a plastomeric polymer, has been widely studied, limited research provides a direct comparison of their effectiveness at both the binder and mixture levels under extremely high-temperature conditions. This study addresses this gap

... Show More
View Publication
Scopus (9)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Al-khwarizmi Engineering Journal
A Review of the Stereo lithography 3D Printing Process and the Effect of Parameters on Quality
...Show More Authors

Stereo lithography (SLA) three-dimensional (3D) printing process is a type of additive manufacturing techniques that uses digital models from computer-aided design to automatically produce customized 3D objects. Around 30 years, it has been widely utilized in the manufacturing, design, engineering, industrial sectors and its applications in dentistry for manufacturing prosthodontics are very important. The stereo lithography technology is highly regarded because it can produce items with excellent precision especially when selecting the best process parameters. This review article offers a useful and scientific summary of SLA three-dimensional printing technology and its brief history. The specific type of 3D printers which is SLA type b

... Show More
View Publication Preview PDF
Scopus (28)
Crossref (26)
Scopus Crossref
Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
A specimen of the internal control system on the stock in light of the application JIT system In construction companies
...Show More Authors

Suffer most of the facilities of the high cost of inventory , which affects the high cost of the product and thus affects many administrative decisions , as well as suffer the facilities of the systems developed by the provisions of inventory control , and this problem is exacerbated in the construction sector where the inventory in the form of Construction spin of the Year for another it becomes difficult to control the cost effectively , and is the research problem in question follows: What are the implications of the use of the system in time inventory accounting system for the contracting company does kills Alrkaah to the provisions of the cost of inventory and what is the optimal approach to inventory control ? Find assumed

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jan 05 2022
Journal Name
International Journal Of Early Childhood Special Education
The effect of single superset exercises on the maximum strength of the limb muscles in bodybuilding for players (Classic Physique).
...Show More Authors

HR Ghanim, GA Abdulhassan, International Journal of Early Childhood Special Education, 2022

View Publication
Publication Date
Fri Jan 02 2026
Journal Name
Journal Of Educational And Psychological Research
The Effect of the Note-Taking Strategy (CORNELL) on the Achievement of Chemistry among Second-Year Middle School Female Students
...Show More Authors

The current research aims to identify the effect of the Cornell note-taking strategy on the achievement of chemistry among second-grade female students in government daytime middle schools. Al-Fadhila School was chosen intentionally as its student sample, affiliated with the First Karkh Directorate for the academic year (2024-2025). One of the two classes was then chosen to represent the experimental group, taught according to the Cornell note-taking strategy, and the other class, the control group, was taught according to the traditional method. The equivalence of the two research groups was verified using a set of variables, including chronological age calculated in months, the Raven Intelligence Test, previous achievement in chemistry, a

... Show More
Publication Date
Fri Aug 25 2023
Journal Name
Enterprenuership Journal For Finance And Bussiness
Argumentative Accounting conservatism and the performance of institutions listed on the Iraq Stock Exchange in light of the Coronavirus pandemic
...Show More Authors

This study aims to test whether the institutions listed on the Iraq Stock Exchange have a significant correlation between the level of conservative accounting practice with the level of market share returns during the Coronavirus pandemic period as one of the policies to confront the economic repercussions of the Coronavirus pandemic. Furthermore, the sample included institutions listed on the Iraq Stock Exchange during the 2019 and 2020 years, i.e., the period before the Coronavirus pandemic and during the Coronavirus pandemic for the purpose of comparison. The market value to book value model was used, and the study found that conservative institutions had achieved the highest level of market share prices compared to non-conservat

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Sun Jul 01 1990
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
THE INFLUENCE OF TEMPERATURE AND HUMIDITY ON THE BIOLOGY OF THE HOUSE DUST MITE DERMATOPHAGOIDES PTERONYSSINUS TROUESSART 1897 (ACARI : PYROGLYPHIDAE)
...Show More Authors

Duration of each developmental stage of the house dust mite Dermatophagoides pteronyssinus together with the mortality percentage were observed at a combination of five different temperatures namely 20C°, 22.5C°, 25C°, 27.5C° and 30C° and four different humidities namely 55%, 75%, 85% and 95% r. h. Results showed that temperature had the greatest effect on the life cycle period. The higher the temperature the shorter the life cycle was aid versa verea. On the other hand, humidity seems to be less effectiveness, though at the higher temperature and humidity no development was occured. Mortality among all temperatures and humidities appeared nearly the same, but at higher temperature and higher humidity and because of mould g

... Show More
View Publication Preview PDF