Preferred Language
Articles
/
ijl-230
Pulsed Er,Cr:YSGG Laser For Surface Modification of Dental Zerconia Ceramic
...Show More Authors

Background: Surface treatment of machined dental zirconia for enhancement of the adhesion to resin cement, using Er,Cr:YSGG  Laser. Materials and Methods: Total number of 42 zirconia disc specimens (9 mm diameter, and 2 mm height) was sintered according to the manufacturer instruction. They are divided into six groups, each group of seven samples. Laser groups (Experiment parameters) were depend on laser total irradiation time, pulse duration, and power. Group (A): 20 sec., 60 µs pulse duration. Group (B): 30 sec., 60 µs pulse duration. Group (C): 40 sec., 60 µs pulse duration. Group (D): 20 sec., 700 µs pulse duration. Group (E): 30 sec., 700 µs pulse duration, with different powers used (1, 1.50, 2, 2.50, 3, 3.50, 4) W. And finally group (N): untreated samples representing the control group. Luting cement was applied to laser treated zirconia sample’s surfaces and cured by light for 40 s. Then all sample surfaces were examined under a stereo microscope, for determining the depth mean values of the created pulse holes, for each specimen. The bond between the laser treated zirconia surfaces and the applied resin cement, were examined for all samples by using a universal testing machine, for determination of the shear bond strength values. Six additional specimens: one untreated sample and five other samples that were laser irradiated with the parameters that exhibited the highest shear bond strength values in each treated group, were examined for their average surface roughness by using an atomic force microscope. Another similar six specimens were also examined for their surface morphology, by using a scanning electron microscope. Both surface examination methods were performed by specialized operators. The bond failure modes were also examined by an optical microscope. Results obtained from shear bond strength test and laser pulse depth examination were statistically analyzed. Results: There was significant differences in the shear bond strength values, indicating a clear increase in zirconia-resin cement bonding, especially in group B (30 s, 60 µs, 4W), reaching  (8.63 Mpa). Whereas, the control group had (4.49 Mpa), and an enhanced zirconia surface average roughness, that group E (30 s, 700 µs, 3.5 W) specimen had the highest value (14.5nm), among the six examined specimens. While the control specimen had the least value examined which is (3.05nm). Conclusion: A relation between the cement bonding efficiency and the laser treated zirconia surface roughness, laser pulse depths was detected. The Er,Cr:YSGG laser pulse duration and  power is  crucial parameters in the surface roughness enhancement of the zirconia ceramic.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Jan 01 2024
Journal Name
Ieee Access
A Direct Solution Scheme for Wide-Angle Electromagnetic Scattering Problems Using Compressive Sensing-Based Method of Moments
...Show More Authors

View Publication
Scopus Clarivate Crossref
Publication Date
Sun Apr 06 2014
Journal Name
Journal Of Economics And Administrative Sciences
Modeling Absolute Deviations Method by using Numerical Methods to measure the dispersion of the proposal for error
...Show More Authors

Is in this research review of the way minimum absolute deviations values ​​based on linear programming method to estimate the parameters of simple linear regression model and give an overview of this model. We were modeling method deviations of the absolute values ​​proposed using a scale of dispersion and composition of a simple linear regression model based on the proposed measure. Object of the work is to find the capabilities of not affected by abnormal values by using numerical method and at the lowest possible recurrence.

 

View Publication Preview PDF
Crossref
Publication Date
Sun Feb 10 2019
Journal Name
Iraqi Journal Of Physics
Matter density distribution and longitudinal form factors for the ground and excited states of 17Ne exotic nucleus
...Show More Authors

The two-frequency shell model approach is used to calculate the
ground state matter density distribution and the corresponding root
mean square radii of the two-proton17Ne halo nucleus with the
assumption that the model space of 15O core nucleus differ from the
model space of extra two loosely bound valence protons. Two
different size parameters bcore and bhalo of the single particle wave
functions of the harmonic oscillator potential are used. The
calculations are carried out for different configurations of the outer
halo protons in 17Ne nucleus and the structure of this halo nucleus
shows that the dominant configuration when the two halo protons in
the 1d5/2 orbi

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Feb 01 2024
Journal Name
Baghdad Science Journal
Estimating the Parameters of Exponential-Rayleigh Distribution for Progressively Censoring Data with S- Function about COVID-19
...Show More Authors

The two parameters of Exponential-Rayleigh distribution were estimated using the maximum likelihood estimation method (MLE) for progressively censoring data. To find estimated values for these two scale parameters using real data for COVID-19 which was taken from the Iraqi Ministry of Health and Environment, AL-Karkh General Hospital. Then the Chi-square test was utilized to determine if the sample (data) corresponded with the Exponential-Rayleigh distribution (ER). Employing the nonlinear membership function (s-function) to find fuzzy numbers for these parameters estimators. Then utilizing the ranking function transforms the fuzzy numbers into crisp numbers. Finally, using mean square error (MSE) to compare the outcomes of the survival

... Show More
View Publication Preview PDF
Scopus (2)
Scopus Crossref
Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Comparison some of methods wavelet estimation for non parametric regression function with missing response variable at random
...Show More Authors

Abstract

 The problem of missing data represents a major obstacle before researchers in the process of data analysis in different fields since , this problem is a recurrent one in all fields of study including social , medical , astronomical and clinical experiments .

The presence of such a problem within the data to be studied may influence negatively on the analysis and it may lead to misleading conclusions , together with the fact that these conclusions that result from a great bias caused by that problem in spite of the efficiency of wavelet methods but they are also affected by the missing of data , in addition to the impact of the problem of miss of accuracy estimation

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Dec 31 2013
Journal Name
Al-khwarizmi Engineering Journal
Design of an Adaptive PID Neural Controller for Continuous Stirred Tank Reactor based on Particle Swarm Optimization
...Show More Authors

 A particle swarm optimization algorithm and neural network like self-tuning PID controller for CSTR system is presented. The scheme of the discrete-time PID control structure is based on neural network and tuned the parameters of the PID controller by using a particle swarm optimization PSO technique as a simple and fast training algorithm. The proposed method has advantage that it is not necessary to use a combined structure of identification and decision because it used PSO. Simulation results show the effectiveness of the proposed adaptive PID neural control algorithm in terms of minimum tracking error and smoothness control signal obtained for non-linear dynamical CSTR system.

View Publication Preview PDF
Publication Date
Mon Aug 18 2025
Journal Name
Soil And Sediment Contamination: An International Journal
Remediation Prediction of Contaminated Soil with Crude Oil Using the Optimized Remediation Method for the Iraqi Environment
...Show More Authors

Large quantities of petroleum-contaminated soil are generated with increased global energy consumption and crude oil production. This theoretical study evaluates the treatment of 1 ton of petroleum-contaminated soil using seven methods: incineration, physical washing, chemical washing, thermal pyrolysis, Fenton-oxidation-pyrolysis, the biological treatment, and asphaltenes. Data were based on experimental results from the Nahran Bin Omar oil lake in Basra Governorate, Iraq, (2019–2021). The methods were compared by waste generation, treatment cost, and duration. Results indicate that using petroleum-contaminated soil as a raw material for asphalt manufacturing is most beneficial since it is sold as a raw material. Incineration is faster a

... Show More
View Publication
Scopus Crossref
Publication Date
Mon Nov 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Building a model to reduce the cost of hajj in the Iraqi Authority for Hajj and Umrah
...Show More Authors

The research is summarized in the construction of a mathematical model using the most common methods in the science of Operations Research, which are the models of transportation and linear programming to find the best solution to the problem of the high cost of hajj in Iraq, and this is done by reaching the optimum number of pilgrims traveling through both land ports and the number Ideal for passengers traveling through airports by Iraqi Airways, instead of relying on the personal experience of the decision-maker in Hajj and Umrah Authority by identifying the best port for pilgrim's travel, which can tolerate right or wrong, has been based on scientific methods of Operations Research, the researcher built two mathematical models

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2017
Journal Name
Engineering And Technology Journal
Study of the Diffusion Coefficient and Hardness for a Composite Material when Immersed in Different Solutions Polymer
...Show More Authors

View Publication
Crossref (1)
Crossref
Publication Date
Sat May 04 2024
Journal Name
Chemchemtech
HPLC METHOD FOR THE DETERMINATION OF SOME ANTIBIOTIC RESIDUES IN DIFFERENT HOSPITALS WASTEWATER IN BAGHDAD CITY, IRAQ
...Show More Authors

Antibiotics present the greatest threat to soil and aquatic ecosystems among the different therapeutic groups of medicines (which include prescription drugs and treatments for cancer). The strongest drugs, antibiotics, have been utilized to stop the growth of microorganisms or eradicate them. Using high-performance liquid chromatography technology with fluorescence detection, the amounts of levofloxacin and tetracycline in the wastewater from three hospitals (Medical City, AlKindi, and Al-Yarmouk) were determined. Levofloxacin and tetracycline were chosen in this study because they are the most important water pollutants. These antibiotic residues were separated and measured using a gradient elution technique on a reverse-phase C18 co

... Show More
Scopus (10)
Scopus