Preferred Language
Articles
/
alkej-511
Finite Element Based Solution of Laplace's Equation Applied to Electrical Activity of the Human Body
...Show More Authors

Computer models are used in the study of electrocardiography to provide insight into physiological phenomena that are difficult to measure in the lab or in a clinical environment.

The electrocardiogram is an important tool for the clinician in that it changes characteristically in a number of pathological conditions. Many illnesses can be detected by this measurement. By simulating the electrical activity of the heart one obtains a quantitative relationship between the electrocardiogram and different anomalies.

Because of the inhomogeneous fibrous structure of the heart and the irregular geometries of the body, finite element method is used for studying the electrical properties of the heart.

This work describes the implementation of the Conjugate Gradient iterative method for the solution of large linear equation systems resulting from the finite element method. A diagonal Jacobi preconditioner is used in order to accelerate the convergence. Gaussian elimination is also implemented and compared with the Precondition Conjugate Gradient (PCG) method and with the iterative method. Different types of matrix storage schemes are implemented such as the Compressed Sparse Row (CSR) to achieve better performance. In order to demonstrate the validity of the finite element analysis, the technique is adopted to solve Laplace's equation that describes the electrical activity of the human body with Dirichlet and Neumann boundary conditions. An automatic mesh generator is built using C++ programming language.  Initially a complete finite element program is built to solve Laplace's equation. The same accuracy is obtained using these methods. The results show that the CSR format reduces computation time compared to the order format. The PCG method is better for the solution of large linear system (sparse matrices) than the Gaussian Elimination and back substitution method, while Gaussian elimination is better than iterative method.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Dec 20 2017
Journal Name
Materials Science-poland
Preparation and electrical properties of polyimide/carbon nanotubes composites
...Show More Authors
Abstract<p>Polyimide/MWCNTs nanocomposites have been fabricated by solution mixing process. In the present study, we have investigated electrical conductivity and dielectric properties of PI/MWCNT nanocomposites in frequency range of 1 kHz to 100 kHz at different MWCNTs concentrations from 0 wt.% to 15 wt.%. It has been observed that the electrical conductivity and dielectric constants are enhanced significantly by several orders of magnitude up to 15 wt.% of MWCNTs content. The electrical conductivity increases as the frequency is increased, which can be attributed to high dislocation density near the interface. The rapid increase in the dielectric constant at a high MWCNTs content can be explained by the form</p> ... Show More
View Publication
Scopus (42)
Crossref (38)
Scopus Clarivate Crossref
Publication Date
Fri Jul 01 2011
Journal Name
Energy
Experimental and numerical analysis of electrical metal foam heater
...Show More Authors

A novel concept of air heater using a heating element made from Aluminum metal porous disc surrounded by a DC resistive electrical heater inserted in the mid-plane of a copper tube of (52.8 mm) diameter and (480 mm) length is presented herein. Study of the developed heater is conducted; using different porous disc thicknesses of (20, 40, 60 mm), heater wall temperatures (106 °C and 119 °C), and flow rates rare varied from (100–300 L/min). Al-metal foam disc has been made using the metal powder technology. Different resistive electrical heaters according to the type of porous disc used have been manufactured. A 2-D computational model is developed, using continuity, momentum, and energy equations for turbulent forced flow in plain tube,

... Show More
View Publication
Scopus (13)
Crossref (10)
Scopus Crossref
Publication Date
Sat Nov 12 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The possibility of adopting a market approach to measure the fair value of biological assets in Iraq: (Applied study in Middle East Fish Production and Marketing Company)
...Show More Authors

The research aims to show the possibility of adopting the market approach to measure the fair value of biological assets in Iraq, by applying to a sample of the company listed on the Iraq Stock Exchange, where the Middle East Fish Production and Marketing Company was selected from among 7 companies representing the agricultural sector in Iraq, and according to the availability of data and for five years, the financial statements were presented of the measurement and disclosure of  biological assets at fair value according to the market approach, One of the most important conclusions reached by the researcher is the The possibility of measuring and disclosing biological assets at fair value according to the market approach in the Ira

... Show More
View Publication Preview PDF
Publication Date
Sun Mar 17 2019
Journal Name
Baghdad Science Journal
Enhancement of Hydrothermally Co3O4 Thin Films as H2S Gas Sensor by Loading Yttrium Element
...Show More Authors

The gas sensing properties of Co3O4 and Co3O4:Y nano structures were investigated. The films were synthesized using the hydrothermal method on a seeded layer. The XRD, SEM analysis and gas sensing properties were investigated for Co3O4 and Co3O4:Y thin films. XRD analysis shows that all films are polycrystalline in nature, having a cubic structure, and the crystallite size is (11.7)nm for cobalt oxide and (9.3)nm for the Co3O4:10%Y. The SEM analysis of thin films obviously indicates that Co3O4 possesses a nanosphere-like structure and a flower-like structure for Co3O4:Y.

The sen

... Show More
View Publication Preview PDF
Scopus (5)
Scopus Clarivate Crossref
Publication Date
Fri Jul 24 2020
Journal Name
Al-kindy College Medical Journal
Serum Ferritin and Body Mass Index in Chronic Telogen Effluvium among women attending the main dermatological outpatient clinics in BaghdadSerum Ferritin and Body Mass Index in Chronic Telogen Effluvium among women attending the main dermatological
...Show More Authors

Background: Hair loss is a common distressing disease and challenging problem for many dermatologist. Telogen effluvium is the most common hair loss disease in which nutritional deficiencies may precipitate the disease through their effect on hair structure and growth.

Study Aim : Validating role of serum ferritin level and body mass index in Chronic Telogen Effluvium and analyzing association between these factors with socioeconomic, demographic, gynecological factors and weight loss effect. Establishing a nutritional preventive advice to improve treatment successfulness and decrease the disease occurrence.

             

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Nov 30 2018
Journal Name
Oriental Journal Of Chemistry
Viscosity and Density Studies of Drugs in Aqueous Solution and in Aqueous Threonine Solution at 298.15 K
...Show More Authors

Viscosities (η) and densities (ρ) of atenolol and propranolol hydrochloride in water and in concentrations (0.05 M) and (0.1 M) aqueous solution of threonine have been used to reform different important thermodynamic parameters like apparent molal volumes fv partial molal volumes at infinite dilution fvo , transfer volume fvo (tr), the slop Sv , Gibbs free energy of activation for viscous flow of solution ΔG*1,2 and the B-coefficient have been calculated using Jones-Dole equation. These thermodynamic parameters have been predicted in terms of solute-solute and solute-solvent interaction.

Publication Date
Mon Feb 25 2019
Journal Name
Oriental Journal Of Chemistry
Viscosity and Density Studies of Drugs in Aqueous Solution and in Aqueous Threonine Solution at 298.15 K
...Show More Authors

View Publication
Crossref (4)
Crossref
Publication Date
Thu Jun 30 2011
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
A PARTICULAR SOLUTION OF THE TWO AND THREE DIMENSIONAL TRANSIENT DIFFUSION EQUATIONS
...Show More Authors

A particular solution of the two and three dimensional unsteady state thermal or mass diffusion equation is obtained by introducing a combination of variables of the form,
η = (x+y) / √ct , and η = (x+y+z) / √ct, for two and three dimensional equations
respectively. And the corresponding solutions are,
θ (t,x,y) = θ0 erfc (x+y)/√8ct and θ( t,x,y,z) =θ0 erfc (x+y+z/√12ct)

View Publication Preview PDF
Publication Date
Sat Dec 28 2024
Journal Name
Journal Of Physical Education
The effect of using special intense exercise accompanied by intermittent electrical stimulation to get rid of lower neck pain among professors of the College of Science - University of Baghdad for ages (40-60) years
...Show More Authors

Lower neck pain is one of the problems facing all ages, especially the elderly, as it revolves around the causes of this pain from many diverse factors. The aim of the research is to use special intense exercise accompanied by intermittent electrical stimulation to get rid of lower neck pain among professors of the College of Science - University of Baghdad for ages. (40-60) years and to identify the extent of the effect. The research assumed the presence of statistically significant differences. The research sample represented professors at the University of Baghdad - College of Science who suffer from continuous pain for the period between (10/15/2023) and (1/15/) 2024) and their number is (5), The researchers used the experimenta

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 02 2011
Journal Name
Al-khwarizmi Engineering Journal
Biomechanical Concept Design of Artificial Human Hand
...Show More Authors

This work is focused on the design parameters and activity of artificial human finger for seven grips. At first, obtained the ideal kinematics of human fingers motion by analyzing the grips video which were recorded using a single digital camera recorder fitted on a tripod in sagital plane while the hand is moving. Special motion analysis software (Dartfish) the finger joint angles were studied using the video recording. Then the seven grips were modeled using static torque analysis, which calculates the amount of torque applied on the fingers joint grip depending on the results of the kinematic analysis. The last step of the work was to design the actuator (Muscle Wire) of artificial finger for the seven grips in a simple design approac

... Show More
View Publication Preview PDF