Preferred Language
Articles
/
alkej-569
Time Prediction of Dynamic Behavior of Glass Fiber Reinforced Polyester Composites Subjected to Fluctuating Varied Temperatures
...Show More Authors

The reduction of vibration properties for composite material (woven roving E-glass fiber plies in thermosetting polyester matrix) is investigated at the prediction time under varied combined temperatures (60  to -15) using three types of boundary conditions like (CFCF, CCCF, and CFCC). The vibration properties are the amplitude, natural frequency, dynamic elastic moduli (young modulus in x, y directions and shear modulus in 1, 2 plane) and damping factor. The natural frequency of a system is a function of its elastic properties, dimensions, and mass. The woven roving glass fiber has been especially engineered for polymer reinforcement; but the unsaturated thermosetting polyester is widely used, offering a good balance of vibration properties at moderate or ambient temperatures, and also at relatively low cost. The mismatch between matrix and fiber yarns gives a predominant role for the fiber's mechanics where the matrix is the area where most damage mechanisms develop. The free vibration test was carried out for (5, 10, 15, 20, 25, 30) minutes. The composite plate was exposed to (75) of thermal gradient for ten times in various times at different stages. The results were classified into experimental and finite element using software ANSYS Ver. 9.    

View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
A Comparison Between Recursive Least-Squares (RLS) and Extended Recursive Least-Squares (E-RLS) for Tracking Multiple Fast Time Variation Rayleigh Fading Channel
...Show More Authors

In order to select the optimal tracking of fast time variation of multipath fast time variation Rayleigh fading channel, this paper focuses on the recursive least-squares (RLS) and Extended recursive least-squares (E-RLS) algorithms and reaches the conclusion that E-RLS is more feasible according to the comparison output of the simulation program from tracking performance and mean square error over five fast time variation of Rayleigh fading channels and more than one time (send/receive) reach to 100 times to make sure from efficiency of these algorithms.

View Publication Preview PDF
Publication Date
Sun Jul 02 2017
Journal Name
Journal Of Educational And Psychological Researches
The effectiveness of instructional design according to whole brain theory of Herman in the achievement of chemistry of the fifth scientific students
...Show More Authors

The research aimed to identify the effectiveness of instructional design according to whole brain theory of Herman in the achievement of chemistry at the fifth scientific students at a secondary school of the General Directorate for Educational in Diyala / Baladruz in Iraq. The research sample Consisted of (57 student, (29) students as experimental group studied according to instructional design strategies for whole brain theory of Herrmann and (28) a student as a control group studied by the usual way for two semesters, a prepared achievement test as article and objective type of multiple choice, the coefficient stability of alpha-Cronbach equation reached (0.86). The research Results showed the presence of a statistically significant d

... Show More
View Publication Preview PDF
Publication Date
Fri Jan 11 2019
Journal Name
Iraqi Journal Of Physics
Structural and optical properties for PVA- PEG-MnCl2 composites
...Show More Authors

Polymer films of PEG and PVA and their blend with different
concentrations of MnCl2 (0, 2, 4, 6 and 10 %.wt) were study using
casting technique. The X-ray spectra of pure PEG, PVA and
PVA:PEG films and with addition of 2% concentrations from
(MnCl2) show amorphous structures. The results for FTIR show the
interaction between the filler and polymer blend results in
decreasing crystallinity with rich amorphous phase. This
amorphous nature confirms the complexation between the filler and
the polymer blend. The optical properties of (PVA:PEG/MnCl2)
contain the recording of absorbance (A) and explain that the
absorption coefficient (α), refractive index (n), extinction coefficient
(ko) and the dielectric cons

... Show More
View Publication Preview PDF
Crossref (9)
Crossref
Publication Date
Sun Jan 13 2019
Journal Name
Iraqi Journal Of Physics
Optical properties for prepared polyaniline / Ferro fluid nano composites
...Show More Authors

Pure nano Ferro fluid was synthesized by chemical co-precipitation method. The composite of polyaniline with nano sized Ferro fluid was prepared by In-situ–chemical oxidation polymerization method with ammonium per sulphate as an oxidant in aqueous hydrochloric acid under constant stirring at room temperature. The optical properties, absorption, transmission, optical energy gap (Eg) and optical constant refractive index (n) have been investigated. The value of the Eg decreased with increasing Ferro fluid concentration.

View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Thu Mar 01 2012
Journal Name
Al-khwarzmi Engineering Journal
Dynamic response analysis for the parabolic trough of solar collector
...Show More Authors

parabolic trough

Publication Date
Sat Nov 01 2014
Journal Name
Al-khwarizmi Engineering Journal
Experimental and Theoretical Investigation of Impact Dynamic Plasticity for CK45
...Show More Authors

Abstract

This paper represents a study of the effect of the soil type, the drilling parameters and the drilling tool properties on the dynamic vibrational behavior of the drilling rig and its assessment in the drilling system. So first, an experimental drilling rig was designed and constructed to embrace the numerical work.

The experimental work included implementation of the drill-string in different types of soil with different properties according to the difference in the grains size, at different rotational speeds (RPM), and different weights on bit (WOB) (Thrust force), in a way that allows establishing the charts that correlate the vibration acceleration, the rate of penetration (ROP), and the power

... Show More
View Publication Preview PDF
Publication Date
Sat Mar 01 1997
Journal Name
Polymer-plastics Technology And Engineering
Feasibility of Dynamic Acid Corrosion Control in Oil Well Tubing
...Show More Authors

View Publication
Scopus (5)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Tue Feb 21 2023
Journal Name
Journal Of Risk And Financial Management
A Multidimensional View of Intellectual Capital and Dynamic Innovative Performance
...Show More Authors

A review of the literature on intellectual capital development was conducted using systemic criteria for the inclusion of relevant studies. The concepts behind the ideas explored in the present study were discussed in respect to the subject matter. Examining the past state of the art in the intellectual capital sector for achieving high levels of innovation performance provided a multidimensional picture of intellectual capital, innovation performance, and dynamic capabilities. The present review was designed to illustrate the correlation between intellectual capital and innovation performance, as well as the role of dynamic capabilities in moderating the relationship between these constructs. Accordingly, we presented an extensive

... Show More
View Publication
Scopus (50)
Crossref (38)
Scopus Crossref
Publication Date
Sat Jun 15 2019
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluation of The Microleakage of Polyacid Modified Composite Compared to Hybrid Composite and Resin Modified Glass Ionomer Cement in Primary and Permanent Teeth Restoration (An in vitro study)
...Show More Authors

Background: Dental caries is one of the most significant problems in world health care. Restoring carious primary teeth is one of the major treatment goals for Children, and the light activated resin restoration materials like composite, resin-modified glass ionomer and polyacid-modified which was introduced in dentistry in 1970, widely used in clinical dentistry but its application increased dramatically in recent years because of its biocompatibility, color matching, good adhesive properties of its resemblance in physical and mechanical aspects to tooth. The aim of this study: To evaluate the microleakage of Polyacid-Modified Composite resin Compared to Flowable Hybrid Composite and Resin-Modified Glass ionomer cement. Materials and me

... Show More
View Publication
Scopus (6)
Crossref (4)
Scopus Crossref
Publication Date
Fri Feb 01 2019
Journal Name
Sci.int.(lahore)
TIME MANAGEMENT AND ITS RELATIONSHIP TO THE STAFF PERFORMANCE IN THE FACULTIES OF PHYSICAL EDUCATION AND SPORTS SCIENCES AT UNIVERSITY OF BAGHDAD
...Show More Authors

The study aimed to identify the importance of time in the Faculties of Physical Education and Sports Sciences at the University of Baghdad, as well as to identify the relationship between time management and the level of staff functional performance. The research population consisted of the staff members who work in the Faculties of Physical Education and Sports Sciences for Girls in Al-Jadriya for the academic year 2017-2018. A random sample of 50 staff members from each faculty were selected, that is the total number was (100) staff members. The researchers identified the concept of time management and functional performance, after that a questionnaire consisting of (39) statements and (6) parts presented to a specialized group of experts

... Show More