Preferred Language
Articles
/
OBdc4I4BVTCNdQwCYFl_
Absorption Coefficient of a Double-Layer Inhomogeneous Micro-perforated Panel Backed with Multiple Cavity Depths
...Show More Authors

Double-layer micro-perforated panels (MPPs) have been studied extensively as sound absorption systems to increase the absorption performance of single-layer MPPs. However, existing proposed models indicate that there is still room for improvement regarding the frequency bands of absorption for the double-layer MPP. This study presents a double-layer MPP formed with two single MPPs with inhomogeneous perforation backed by multiple cavities of varying depths. The theoretical formulation is developed using the electrical equivalent circuit method to calculate the absorption coefficient under a normal incident sound. The simulation results show that the proposed model can produce absorption coefficient with wider absorption bandwidth compared with the conventional double- and even triple-layer MPPs. The bandwidth can be increased to higher frequency by decreasing the cavity depth behind a sub-MPP with small hole diameter and a high perforation ratio, and to lower frequency by increasing the cavity depth behind a sub-MPP with large hole diameter and a small perforation ratio. The experimental data, measured by impedance tube, are in good agreement with the predicted results.

Scopus Clarivate Crossref
View Publication
Publication Date
Sun Sep 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Sharing knowledge on organizational innovation Field study in the arab company , for detergents and chemical
...Show More Authors

ABSTRACT

Impkact  of  Knowledge  sharing  on  organizational  innovation  Impriscal  study in Arabic company . 

of  Knowledge Management is  the  main  component  Knowledge  sharing  system, it mean the exchange if  Knowledge, ideas, and good  practice with  another  individual . Knowledge sharing between persons, then its values can growth .

It is vry important because it can provide us with the contention between virus peoples . the interaction among the people can pass all kind of Knowledge among them. the connection and interaction and interaction enabl

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Association Of Arab Universities Journal Of Engineering Sciences
Experimental and numerical investigation on the behavior of reinforced reactive powder concrete two-way slabs under static load
...Show More Authors

This paper studied the behaviour of reinforced reactive powder concrete (RPC) two-way slabs under static load. The experimental program included testing three simply supported slabs of 1000 mm length, 1000 mm width, and 70 mm thickness. Tested specimens were of identical properties except their steel fibers volume ratio (0.5 %, 1 %, and 1.5 %). Static test results revealed that, increasing steel fibers volume ratio from 0.5% to 1% and from 1% to 1.5%, led to an increase in: first crack load by (32.2 % and 52.3 %), ultimate load by (36.1 % and 17.0 %), ultimate deflection by (33.6 % and 3.4 %), absorbed energy by (128 % and 20.2 %), and the ultimate strain by (1.1 % and 6.73 %). The stiffness and ductility of the specimens also increased. A

... Show More
View Publication
Publication Date
Thu Mar 30 2023
Journal Name
Journal Of Economics And Administrative Sciences
Using the Critical Path Method to Find Time of Constriction for Helicopters Airport Project in the Oil Fields
...Show More Authors

This research is considered one of the important researches in Maysan Governorate, as it focuses on the construction of helicopter airport project in the oil fields of the Maysan Oil Company, where the oil general companies in Maysan Governorate suffer from the cost of transporting the foreign engineering experts and the governing equipment of sustaining oil industry from Iraq's international airports to oil fields and vice versa. Private international transport companies transport foreign engineering from the oil fields to Iraqi airports and vice versa, and other international security companies take action to provide protection for foreign engineering experts during transportation. Hence, this process is very costly.

 &nbs

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Dec 15 2022
Journal Name
Journal Of Baghdad College Of Dentistry
Experimental In vitro Study to Assess the Antibacte-rial Activity of Thymus vulgaris Oil on Streptococ-cus Sanguinis
...Show More Authors

Background: The Streptococcus genus are the predominant bacteria in the mouth and the Streptococcus sanguinis is one of them which performing a primary function for expansion of dental biofilm. Gingival and periodontal disorders are caused by dental biofilm, today, there is a necessity to discover naturally presenting antibacterial compounds from herbs with less side effects as a substitutive to the commonly handled chlorohexidine. Thus, the purpose of this study was to assess the antibacterial activity of thymus vulgaris oil on Streptococcus sanguinis bacteria In vitro. Materials and Methods: Human supragingival plaque samples were taken from 10 subjects, then morphological and microscopical examination, bioch

... Show More
View Publication Preview PDF
Scopus (3)
Crossref (2)
Scopus Crossref
Publication Date
Wed Jan 08 2025
Journal Name
Journal Of Al-rafidain University College For Sciences ( Print Issn: 1681-6870 ,online Issn: 2790-2293 )
Utilizing the Error Correction Model to Investigate the Impact of Fluctuations in Bank Deposits on the Money Supply
...Show More Authors

This paper assesses the impact of changes and fluctuations in bank deposits on the money supply in Iraq. Employing  the research constructs an Error Correction Model (ECM) using  monthly time series data from 2010 to 2015. The analysis begins with  the Phillips-Perron unit root test to ascertain the stationarity of the  time series and the Engle and Granger cointegration test to examine  the existence of a long-term relationship. Nonparametric regression functions are estimated using two methods: Smoothing Spline and M-smoothing. The results indicate that the  M-smoothing approach is the most effective, achieving the shortest adjustment period and the highest adjustment ratio for short-term disturbances, thereby facilitating a return

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Sat Mar 04 2023
Journal Name
Baghdad Science Journal
Nordhaus-Gaddum Type Relations on Open Support Independence Number of Some Path Related Graphs Under Addition and Multiplication
...Show More Authors

In this paper, Nordhaus-Gaddum type relations on open support independence number of some derived graphs of path related graphs under addition and multiplication are studied.

View Publication Preview PDF
Scopus Clarivate Crossref
Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Study of opacity broadening in spectral lines for helium like ions in aluminum plasma which produced by laser
...Show More Authors

A theoretical analysis studied was performed to study the opacity broadening of spectral lines emitted from aluminum plasma produced by Nd-YLF laser. The plasma density was in the range 1028-1026 )) m-3 with length of plasma about ?300) m) , the opacity was studied as function of plasma density & principle quantum number. The results show that the opacity broadening increases as plasma density increases & decreases with the spacing between energy levels of emission spectral line.

View Publication Preview PDF
Crossref
Publication Date
Sat Feb 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Assessing the efficiency Economic performance of the diyala General company for electrical industries for the Period (2000-2010)
...Show More Authors


     Facing industrial companies many pressures and challenges due to rapid changes in the business environment of contemporary, which requires them to do their performance look more inclusive rather than limiting performance evaluation on the financial perspective in spite of its importance, prompting companies to rethink their reality competitive through the adoption of methodologies and new philosophies to manage competitiveness of total quality management, and re-engineering of production processes, and knowledge management,... etc., as This study framework cognitive and practical "to evaluate the performance of a company Diyala General Electric Industries and how to rehabilitate

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Tue Sep 15 2020
Journal Name
Al-academy
Transformations of Actor's Performance between the Body and Mask Dualism in Iraqi Child's Theatre Shows: حازم عوده صيوان
...Show More Authors

The Child's theatre was and still is the most investing art for masks of all kinds (partial and total) for suspense, aesthetic and artistic purposes that meet the requirements of those performances. Here the actor's performance is associated with two tools, i.e. the body and the mask, where it has become a must to search for the performance transformations required in order to achieve the highest level of the right performance through this dualism. This urged the researcher to address this problem. Thus, the researcher has put forward an objective to identify the transformations of the character's performance between the body and the mask in the child's theatre shows. The research consists of a methodological framework and a theoretical

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Dec 30 2018
Journal Name
Journal Of Global Pharma Technology
Employing the Physicochemical, Spectroscopy, Antimicrobial and Antifungal Efficacy Studies of P-Hydroxy Acetophenone Based Azo Schiff Base Complexes
...Show More Authors

The azo Schiff base [Reaction of 4-aminoanypyrine and P-hydroxy acetophenone] and O-Phenylene diamine have been prepared. One azo Schiff base chelate of Co(Il), Ni(II), Cu(II) and Zn(II)ion was also prepared. The chemical frameworks of the azo Schiff base and like elemental analyses (CHN), determinations of molar conductance, 1 H &13C NMR, IR mass and electronic spectroscopy .The elemental analyses exhibited the combination of [L: M] 1:1 ratio. Established on the values IR spectral, it is showed that the azo Schiff base compound acts as neutral hexadentate ligand bonded with the metal ion from two hydroxyl, two azomethine and two azo groups of the azo Schiff base compound in chelation was confirmed by IR , 1Hand 13CNMR spectral outco

... Show More
Scopus (3)
Scopus