Preferred Language
Articles
/
joe-1841
On the Laser Micro Cutting: Experimentation and Mathematical Modeling based on RSM-CCD
...Show More Authors

The laser micro-cutting process is the most widely commonly applied machining process which can be applied to practically all metallic and non-metallic materials. While this had challenges in cutting quality criteria such as geometrical precision, surface quality and numerous others. This article investigates the laser micro-cutting of PEEK composite material using nano-fiber laser, due to their significant importunity and efficiency of laser in various manufacturing processes. Design of experiential tool based on Response Surface Methodology (RSM)-Central Composite Design (CCD) used to generate the statistical model. This method was employed to analysis the influence of parameters including laser speed, laser power, laser frequency and number of passes on the cutting characteristics -and geometrical. Cutting-geometry requirements are significant quality features since they are one of the metrics for the geometrical precision of micro-cutting proses it was concluded that higher laser power, slower speed, and more pass number result in a low kerf taper, these parameters have a significant impact on the other cutting characteristics, and geometrical. Whereas the frequency has the lowers impact on the cutting geometrical. Finally, the experiments show Maximum depth was 2000, width minimum top kerf width was 305.56 µm and the minimum angle of 2.8906.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Feb 15 2018
Journal Name
Iraqi Journal Of Laser
Characterization of Gold Coating on Nanostructured CR39 Polymer as SERS Sensor
...Show More Authors

Abstract: The development of highly sensitive sensors has become an efficient field of research. In this work, an ArF Excimer laser of 193 nm with a maximum pulse energy of 275 mJ, 15 ns pulse duration and a repetition rate of 1 Hz is utilized to form a Laser Induced Periodic Surface Structures (LIPSS) of three different morphologies (nanochains, contours, grooves) on surface of CR39 polymer at a fluence range above the ablation threshold (250 mJ/cm2). The laser ablated polymer surface is then Surface Enhanced Raman Scattering (SERS) activated by deposition of a gold layer of 30 nm thickness. The capability of the produced substrate for surface enhanced Raman scattering is evaluated through thiophenol as an analyte molecule. It is observ

... Show More
View Publication Preview PDF
Publication Date
Sun Sep 07 2014
Journal Name
Baghdad Science Journal
Exponential Function of a bounded Linear Operator on a Hilbert Space.
...Show More Authors

In this paper, we introduce an exponential of an operator defined on a Hilbert space H, and we study its properties and find some of properties of T inherited to exponential operator, so we study the spectrum of exponential operator e^T according to the operator T.

View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Mar 04 2018
Journal Name
Baghdad Science Journal
Effect of Cyanobacteria Isolates on Rice Seeds Germination in Saline Soil
...Show More Authors

Cyanobacteria are prokaryotic photosynthetic communities which are used in biofertilization of many plants especially rice plant. Cyanobacteria play a vital role to increase the plant's ability for salinity tolerance. Salinity is a worldwide problem which affects the growth and productivity of crops. In this work three cyanobacteria strains (Nostoc calcicola, Anabaena variabilis, and Nostoc linkia) were isolated from saline soil at Kafr El-Sheikh Governorate; North Egypt. The propagated cyanobacteria strains were used to withstand salinity of the soil and increase rice plant growth (Giza 178). The length of roots and shoot seedlings was measured for seven and forty days of cultivation, respectively. The results of this investigation showed

... Show More
View Publication Preview PDF
Scopus (15)
Crossref (12)
Scopus Clarivate Crossref
Publication Date
Sun Jun 18 2023
Journal Name
International Journal Of Development In Social Sciences And Humanities
A CRITICAL DISCOURSE ANALYSIS OF SELECTED POLITICAL SPEECH ON ONLINE EDUCATION
...Show More Authors

PDBN Rashid, International Journal of Development in Social Sciences and Humanities, 2023

View Publication
Publication Date
Tue Mar 28 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Effect of Administration of Crystalloid IV Fluids Preoperatively on Postoperative Pain
...Show More Authors

Pain is a sensory and emotional experience that is influenced by physiologic, sensory, affective, cognitive, socio-cultural and behavioral factors. Postoperative pain is the commonest reason for delayed discharge and unanticipated hospital admission after ambulatory surgery. Our Objective is to test the hypothesis that administration of 2 ml/kg/hr preoperative IV fluids may attenuates postoperative pain.The study was carried out in the Baghdad Teaching Hospital, Al-Yarmok Teaching Hospital and Al-Karama Teaching Hospital from 12 May till 17 June 2009. The total number of patients was 120 (35 males and 85 females) with their age ranged between 10-90 years. The patients were divided into two groups according to administration of preoperati

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Mar 01 2012
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Predicting changes on budget expenditures using Markov chains with practical application
...Show More Authors

The researchers have a special interest in studying  Markov  chains as one of the probability samples which has many applications in different fields. This study comes to deal with the changes issue that happen on budget expenditures by using statistical methods, and Markov chains is the best expression about that as they are regarded reliable  samples in the prediction process. A transitional matrix is built for three expenditure cases (increase ,decrease ,stability) for one of budget expenditure items (base salary) for three directorates (Baghdad ,Nineveh , Diyala) of one  of the ministries. Results are analyzed by applying  Maximum likelihood estimation  and Ordinary least squares  methods resulting

... Show More
View Publication Preview PDF
Publication Date
Sat Nov 07 2020
Journal Name
Theory And Practice Of Mathematics And Computer Science
Discussion on Bipolar Fuzzy n-fold KU-ideal of KU-algebras
...Show More Authors

Publication Date
Mon Aug 31 2015
Journal Name
International Journal Of Advanced Research
On instability of zero solution of some types of forth order
...Show More Authors

The purpose of this paper is to study the instability of the zero solution of some type of nonlinear delay differential equations of fourth order by using the Lyapunov-Krasovskii functional approach; we obtain some conditions of instability of solution of such equation.

Publication Date
Tue Jan 01 2019
Journal Name
Eurasian Chemico --technological Journal
Influence of addition (Mn) on enhance efficiency of (CuInTe2) photovoltaic cell
...Show More Authors

Publication Date
Tue Sep 01 2015
Journal Name
Journal Of Engineering
Internal Convective Heat Transfer Effect on Iraqi Building Construction Cooling Load
...Show More Authors

This work involves the calculation of the cooling load in Iraqi building constructions taking in account the effect of the convective heat transfer inside the buildings. ASHRAE assumptions are compared with the Fisher and Pedersen model of estimation of internal convective heat transfer coefficient when the high rate of ventilation from ceiling inlet configuration is used. Theoretical calculation of cooling load using the Radiant Time Series Method (RTSM) is implemented on the actual tested spaces. Also the theoretical calculated cooling loads are experimentally compared by measuring the cooling load in these tested spaces. The comparison appears that using the modified Fisher and Pedersen model when large ventilation ra

... Show More
View Publication Preview PDF