Preferred Language
Articles
/
alkej-12
e Timoshenko Three-Beams Technique To Estimate The Main Elastic Moduli Of Orthotropic Homogeneous Materials
...Show More Authors

 A New developed technique to estimate the necessary six elastic constants of homogeneous laminate of special orthotropic properties are presented in this paper for the first time. The new approach utilizes the elasto-static deflection behavior of composite cantilever beam employing the famous theory of Timoshenko. Three extracted strips of the composite plate are tested for measuring the bending deflection at two locations. Each strip is associated to a preferred principal axis and the deflection is measured in two orthogonal planes of the beam domain. A total of five trails of testing is accomplished and the numerical results of the stiffness coefficients are evaluated correctly under the contribution of the macromechanics and the approximate bending theory. To insure the validity of the new approach, separate individual tensile tests are performed, and the corresponding results are compared. Excellent agreements are obtained between the different approaches. The ease, simple and accurate predictions are well confident by the new technique.

 

 

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of classical method and optimization methods for estimating parameters in nonlinear ordinary differential equation
...Show More Authors

 ABSTRICT:

  This study is concerned with the estimation of constant  and time-varying parameters in non-linear ordinary differential equations, which do not have analytical solutions. The estimation is done in a multi-stage method where constant and time-varying parameters are estimated in a straight sequential way from several stages. In the first stage, the model of the differential equations is converted to a regression model that includes the state variables with their derivatives and then the estimation of the state variables and their derivatives in a penalized splines method and compensating the estimations in the regression model. In the second stage, the pseudo- least squares method was used to es

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Jan 01 2015
Journal Name
Journal Of Engineering
Performance Improvement of the Implementation of Concrete Structures in the Construction Sector In Iraq Using The Modern Management Technique “Six Sigma”
...Show More Authors

The reality of the field of construction projects in Iraq refers to needing for the development of performance in order to improve quality and reduce defects and errors and to control the time and cost, so there is needing for the application of effective methods in this area, one of the methods that can be applied in this area is the manner of Six Sigma. This research aims to enhance the performance and quality improvement for the construction projects by improving performance in the work of the implementation of the concrete structure depending on the Six Sigma methodology, and for the purpose of achieving the aim of the research, the researcher firstly depends on the theoretical study that include the concepts of qual

... Show More
View Publication
Publication Date
Fri Jan 02 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Comparative Assessment of In Vitro Effect of Three Fluoride Releasing Agents on Enamel Demineralization around Orthodontic Brackets
...Show More Authors

Background: White spot lesion considered as irreversible tooth demineralization presenting challenge to orthodontists during treatment schedules, fluoride was the most successfully used measure to overcome this challenge. Materials and method: A total of forty sound human permanent premolars were used in the present study and categorized into four groups, in one group the teeth were bonded with stainless steel brackets using Resin-modified glass ionomer cement (RMGIC) and the other three groups the teeth were bonded with light cured composite Resilience® (Ortho technology Co., USA). Group A; Acidulated phosphate fluoride (APF) topical gel (Mfg by DEEPAK PRODUCTS, INC, USA), fluoride ion 1.23% applied on examine area for four minute. Gro

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Oct 12 2018
Journal Name
International Journal Of Dynamics And Control
Decentralized adaptive partitioned approximation control of high degrees-of-freedom robotic manipulators considering three actuator control modes
...Show More Authors

View Publication
Scopus (11)
Crossref (9)
Scopus Crossref
Publication Date
Tue Feb 18 2020
Journal Name
Modelling And Simulation In Engineering
Temperature and Stress Evaluation during Three Different Phases of Friction Stir Welding of AA 7075-T651 Alloy
...Show More Authors

The current study performs an explicit nonlinear finite element simulation to predict temperature distribution and consequent stresses during the friction stir welding (FSW) of AA 7075-T651 alloy. The ABAQUS® finite element software was used to model and analyze the process steps that involve plunging, dwelling, and traverse stages. Techniques such as Arbitrary Lagrangian–Eulerian (ALE) formulation, adaptive meshing, and computational feature of mass scaling were utilized to simulate sequence events during the friction stir welding process. The contact between the welding tool and workpiece was modelled through applying Coulomb’s friction model with a nonlinear friction coefficient value. Also, the model considered the effect of nonlin

... Show More
View Publication Preview PDF
Scopus (43)
Crossref (25)
Scopus Clarivate Crossref
Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Comparative Assessment of in Vitro Effect of Three Fluoride Releasing Agents on Enamel Demineralization around Orthodontic Brackets
...Show More Authors

View Publication
Crossref (2)
Crossref
Publication Date
Thu Apr 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
The Role of E-Learning in enhancing Total Quality Management in Educational Institutions: an exploratory study of the opinions of a sample of the staff of the Directorate of Education in the province of Nineveh
...Show More Authors

Purpose: The research aims to determine the relationship between E-Learning and Total Quality Management (TQM) in Educational institutions in Nineveh Governorates.

Methodology / Design: The researchers distributed (30) questionnaires to employees (teachers and administrators) of Nineveh Governorate education who represent the community of the research sample, as they were analyzed using the SPSS V.20

The importance of research: The importance of the research in the fact that it focuses on one of the educational methods represented in integrating the traditional method and relying on modern technologies using computers and the Internet in the field of education to improve the reali

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Aug 19 2020
Journal Name
Applied Water Science
Spiral path three phase fluidized bed reactor for treating wastewater contaminated with engine oil
...Show More Authors
Abstract<p>In this study, a new type of circulating three-phase fluidized bed reactor was conducted by adding a spiral path and was named as spiral three-phase fluidized bed reactor (TPFB-S) to investigate the possibility for removing engine oil (virgin and waste form) from synthetic wastewater by using Ricinus communis (RC) leaves natural and activated by KOH. The biosorption process was conducted by changing particle diameter in the range 150–300 and 300–600 µm, liquid flow rate in the range 2.5–4.5 L/min and gas flow rate in range of 0–1 L/min, while other parameters initial oil emulsion concentration, pH, adsorbent concentration, agitation speed and contact time were kept constant at 2000 mg/L, 2,</p> ... Show More
View Publication
Scopus (12)
Crossref (10)
Scopus Clarivate Crossref
Publication Date
Sun Jan 01 2023
Journal Name
Journal Of The Mechanical Behavior Of Materials
Transient response and performance of prestressed concrete deep T-beams with large web openings under impact loading
...Show More Authors
Abstract<p>This study reports testing results of the transient response of T-shape concrete deep beams with large openings due to impact loading. Seven concrete deep beams with openings including two ordinary reinforced, four partially prestressed, and one solid ordinary reinforced as a reference beam were fabricated and tested. The effects of prestressing strand position and the intensity of the impact force were investigated. Two values for the opening’s depth relative to the beam cross-section dimensions were inspected under the effect of an impacting mass repeatedly dropped from different heights. The study revealed that the beam’s transient deflection was increased by about 50% with gre</p> ... Show More
View Publication
Scopus (6)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Tue Aug 03 2021
Journal Name
Key Engineering Materials
Comparative Study of Structural Behavior for Asymmetrical Castellated (Concavely - Curved Soffit) Steel Beams with Different Strengthening Techniques
...Show More Authors

The Asymmetrical Castellated concavely – curved soffit Steel Beams with RPC and Lacing Reinforcement improves compactness and local buckling (web and flange local buckling), vertical shear strength at gross section (web crippling and web yielding at the fillet), and net section ( net vertical shear strength proportioned between the top and bottom tees relative to their areas (Yielding)), horizontal shear strength in web post (Yielding), web post-buckling strength, overall beam flexure strength, tee Vierendeel bending moment and lateral-torsional buckling, as a result of steel section encasement. This study presents two concentrated loads test results for seven specimens Asymmetrical Castellated concavely – curved soffit Steel Be

... Show More
View Publication
Scopus (6)
Crossref (4)
Scopus Crossref