Preferred Language
Articles
/
alkej-213
Formation of Compressive Residual Stress by Face Milling Steel AISI 1045
...Show More Authors

Abstract

     Machining residual stresses correlate very closely with the cutting parameters and the tool geometries. This research work aims to investigate the effect of cutting speed, feed rate and depth of cut on the surface residual stress of steel AISI 1045 after face milling operation. After each milling test, the residual stress on the surface of the workpiece was measured by using X-ray diffraction technique. Design of Experiment (DOE) software was employed using the response surface methodology (RSM) technique with a central composite rotatable design to build a mathematical model to determine the relationship between the input variables and the response. The results showed that both the feed rate and the cutting speed are the significant factors controlling the surface residual stress, while the depth of cut had no influence. A quadratic empirical model was developed with a 95% confidence level, and a good agreement was found between the experimental and predicted results. A numerical optimization was then conducted through DOE program to find the optimum surface residual stress at the optimum cutting parameters, depending on the maximum desirability obtained. The optimum compressive surface residual stress (-224.361 MPa) was found at cutting speed of 69.2 m/min, feed rate of 0.4 m/min and depth of cut of 0.4 mm.

Keywords: Face milling, Cutting parameters, Steel AISI 1045, Residual stresses, XRD; DOE, RSM, Modeling and Numerical optimization.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Dec 15 2015
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Determination of some Optimum Conditions for Bioremediation of Some Heavy Metals by Saccharomyces cerevisiae: Determination of some Optimum Conditions for Bioremediation of Some Heavy Metals by Saccharomyces cerevisiae
...Show More Authors

The study aimed to determine of some Optimum conditions for bioremediation and removing of seven mineral elements included hexavalent chromium, nickel, cobalt, cadmium, lead, iron and copper as either alone or in group by living and heat treated cells of baker’s yeast Saccharomyces cerevisiae. The dried baker's yeast from Aldnaamaya China Company was used in this study. Biochemical tests was used to ensure yeast belonging to S. cerevisiae and then used to remove the mentioned mineral elementes under different conditions which included incubation period, pH, and temperature. It was found that the best of these conditions was 60 minutes for duration of incubation, 6 for pH, 25 ᵒC for temperature. During the study the behavior of living

... Show More
View Publication Preview PDF
Publication Date
Thu May 18 2023
Journal Name
Journal Of Engineering
Experimental Study of Power Increase Transient in Heat Generation Systems Simulated By Immersed Heat Source
...Show More Authors

Theoretical and experimental investigations of the transient heat transfer parameters of constant heat flux source subjected to water flowing in the downward direction in closed channel are conducted. The power increase transient is ensured by step change increase in the heat source power. The theoretical investigation involved a mathematical modeling for axially symmetric, simultaneously developing laminar water flow in a vertical annulus. The mathematical model is based on one dimensional downward flow. The boundary conditions of the studied case are based on adiabatic outer wall, while the inner wall is subjected to a constant heat flux. The heat & mass balance equation derived for specified element of bulk water within the annulu

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Mar 01 2019
Journal Name
Iraqi Journal Of Physics
Enhancement of NO2 gas sensing behavior for ZnS/PPy nanostructure by loading graphene
...Show More Authors

The pure ZnS and ZnS-Gr nanocomposite have been prepared
successfully by a novel method using chemical co-precipitation. Also
conductive polymer PPy nanotubes and ZnS-PPy nanocomposite
have been synthesized successfully by chemical route. The effect of
graphene on the characterization of ZnS has been investigated. X-ray
diffraction (XRD) study confirmed the formation of cubic and
hexagonal structure of ZnS-Gr. Dc-conductivity proves that ZnS and
ZnS-Gr have semiconductor behavior. The SEM proved that
formation of PPy nanotubes and the Gr nanosheet. The sensing
properties of ZnS-PPy/ZnS-Gr for NO2 gas was investigated as a
function of operating temperature and time under optimal condition.
The sensitivity,

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jan 02 2019
Journal Name
International Journal Of Agricultural & Statistical Sciences
RESPONSE OF OLIVE SEEDLINGS TO HUMIC ACID AND INOCULATION BY FUNGI (TRICHODERMA SSP) AND THE INTERACTION OF THEM AND IRRIGATION BY SALT WATER ON VEGETATIVE GROWTH.
...Show More Authors

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
Fri Jan 01 2016
Journal Name
Journal Of Engineering
Improve the Performance of PID Controller by Two Algorithms for Controlling the DC Servo Motor
...Show More Authors

The paper uses the Direct Synthesis (DS) method for tuning the Proportional Integral Derivative (PID) controller for controlling the DC servo motor. Two algorithms are presented for enhancing the performance of the suggested PID controller. These algorithms are Back-Propagation Neural Network and Particle Swarm Optimization (PSO). The performance and characteristics of DC servo motor are explained. The simulation results that obtained by using Matlab program show that the steady state error is eliminated with shorter adjusted time when using these algorithms with PID controller. A comparative between the two algorithms are described in this paper to show their effectiveness, which is found that the PSO algorithm gives be

... Show More
View Publication Preview PDF
Publication Date
Sun Feb 03 2019
Journal Name
Iraqi Journal Of Physics
Thickness and gamma-ray effect on physical properties of CdO thin films grown by pulsed laser deposition
...Show More Authors

Polycrystalline Cadmium Oxide (CdO) thin films were prepared
using pulsed laser deposition onto glass substrates at room
temperature with different thicknesses of (300, 350 and 400)nm,
these films were irradiated with cesium-137(Cs-137) radiation. The
thickness and irradiation effects on structural and optical properties
were studied. It is observed by XRD results that films are
polycrystalline before and after irradiation, with cubic structure and
show preferential growth along (111) and (200) directions. The
crystallite sizes increases with increasing of thickness, and decreases
with gamma radiation, which are found to be within the range
(23.84-4.52) nm and (41.44-4.974)nm before and after irradiation for

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
The Writer Authentication by Using Syllables Frequency
...Show More Authors

An approach is depended in the recent years to distinguish any author or writer from other by analyzing his writings or essays. This is done by analyzing the syllables of writings of an author. The syllable is composed of two letters; therefore the words of the writing are fragmented to syllables and extract the most frequency syllables to become trait of that author. The research work depend on analyzed the frequency syllables in two cases, the first, when there is a space between the words, the second, when these spaces are ignored. The results is obtained from a program which scan the syllables in the text file, the performance is best in the first case since the sequence of the selected syllables is higher than the same syllables in

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 12 2019
Journal Name
Dirasat: Human And Social Sciences
Teaching by pause technique in the classroom
...Show More Authors

Communication represents the essence of language learning. Since the unspecified evolution of conveying information, human beings have been employing the main constituents of language with short pauses. Although the punctuation marks necessitate short expressions among thought group of words in writing, human language demand for understanding how and when to pause orally. This paper presents the pause technique in the classroom. It signifies the relation between pausing and lecturing in the class and determines its sufficient time-management to interact with college learners of different specializations. The conduct study reviewed teaching pause technique in the empirical studies at Special Education and Communication Disorders of Pennsylva

... Show More
View Publication Preview PDF
Scopus (1)
Scopus
Publication Date
Sat Dec 01 2012
Journal Name
International Journal Of Contemporary Mathematical Sciences
Approximation by Convex Polynomials in Weighted Spaces
...Show More Authors

Here, we found an estimation of best approximation of unbounded functions which satisfied weighted Lipschitz condition with respect to convex polynomial by means of weighted Totik-Ditzian modulus of continuity