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Effective working parameters of laser micro-/nano-machining
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Modern emerged technologies impose development and fabrication of miniatur-ized parts and devices in the micro- and nano-scale. Producing micro- and nano-featured structures requires nonconventional machining processes where con-ventional machining processes such as grinding, milling and eroding have failed. New emerging processes, such laser machining processes, are still fraught with almost invincible processes. Micro-/nano-machining are the pro-cesses of producing parts, microsystems or features at a scale of a few microm-eters and less than one hundred nanometers, respectively. Precise cutting and clean material removal accompanied with a negligible heat affected zone (HAZ), which are usually the characteristics of laser ablation, have opened a wide door for the evolution of remarkable technologies. This has been demonstrated by applications in different fields such as medicine, biotechnology, materials pro-cessing, microelectromechanical systems, electronics and communications. The continuous development in laser technology in terms of ultra-short pulse width, short wavelength and optics technologies has reduced the drawbacks of diffrac-tion-limited processing accuracies. Laser micro-/nano-machining requires the attainment of high fluence and short interaction time to achieve ablation pro-cesses in nanofabrication and structuring of different materials. To conduct the optimum desired machining process, it is important to integrally consider a number of laser beam and working parameters. Laser wavelength, beam mode, minimum attainable spot size, peak power, pulse duration, pulse repetition rate and scanning speed are some of the important considerations. Manipulating those parameters is crucial for ideal laser ablation represented by yielding the highest resolution of machining with the least lateral dimensions, acceptable depth and minimal or no melt at the edges. The assembly of laser beam delivery and focusing system with an automation system are the essential factors for workpiece positioning and obtaining the desired dimensions. The objective of this chapter is to review the effective parameters associated with laser machin-ing processes that affect the dimensions and quality of laser machining at the micro-/nano-scales in a simple presentation. The review is supported by demonstrating laser processing techniques applied in the field of micro-/nano-machining such as mask, interferometric and scribing techniques.

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Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Engineering
Optimized Zero and First Order Design of Micro Geodetic Networks
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Precision is one of the main elements that control the quality of a geodetic network, which defines as the measure of the network efficiency in propagation of random errors. This research aims to solve ZOD and FOD problems for a geodetic network using Rosenbrock Method to optimize the geodetic networks by using MATLAB programming language, to find the optimal design of geodetic network with high precision. ZOD problem was applied to a case study network consists of 19 points and 58 designed distances with a priori deviation equal to 5mm, to determine the best points in the network to consider as control points. The results showed that P55 and P73 having the minimum ellipse of error and considered as control points. FOD problem was applie

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparing parameters and Reliability of two-parameters exponential
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One of the most important problems in the statistical inference is estimating parameters and Reliability parameter and also interval estimation , and testing hypothesis . estimating two parameters of exponential distribution and also reliability parameter in a stress-strength model.

This parameter deals with estimating the scale parameter and the Location parameter µ , of two exponential distribution   ,using moments estimator and maximum likelihood estimator , also we estimate the parameter R=pr(x>y), where x,y are two- parameter independent exponential random variables .

Statistical properties of this distribution and its properti

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Radioactivity and annual effective dose in some types of drug
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The aim of this research is to know danger of radioactive isotopes
that are found in samples of drugs traded in Iraqi markets. The
samples are Iraqi Amoxicillin, English Amoxicillin, UAE
Amoxicillin, Indian Amoxicillin, Iraqi Paracetamol, English
Paracetamol, UAE Paracetamol and Indian Paracetamol. By high
purity germanium the activity of the following isotopes 40K, 214Pb,
228Ac and 137Cs is measured and the specific activity was used to
calculate the annual effective dose. Then the calculated annual
effective dose values are compared with the allowable annual
effective dose values of each part of digestive channel. This research
concluded that the measured annual effective dose values are not
dangerous.<

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Publication Date
Sun Jan 01 2023
Journal Name
International Conference Of Computational Methods In Sciences And Engineering Iccmse 2021
The effective radius of elliptical galaxies at z &lt; 0.02
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Publication Date
Sun Nov 26 2017
Journal Name
Journal Of Engineering
Experimental Investigation of Nano Alumina and Nano Silica on Strength and Consistency of Oil Well Cement
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In oil and gas well cementing, a strong cement sheath is wanted to insure long-term safety of the wells. Successful completion of cementing job has become more complex, as drilling is being done in highly deviated and high pressure-high temperature wells. Use of nano materials in enhanced oil recovery, drilling fluid, oil well cementing and other applications is being investigated. This study is an attempt to investigate the effect of nano materials on oil well cement properties. Two types of nano materials were investigated, which are Nano silica (>40 nm) and Nano Alumina (80 nm) and high sulfate-resistant glass G cement is used. The investigated properties of oil well cement included compressive strength, thickening

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Publication Date
Tue Jul 29 2025
Journal Name
Journal Of Engineering
Experimental Investigation of Nano Alumina and Nano Silica on Strength and Consistency of Oil Well Cement
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Publication Date
Fri Jun 29 2018
Journal Name
Journal Of The College Of Education For Women
THE PROBLEM RELATED TO WORKING IN KINDERGARTEN FROM THE POINT OF VIEW OF TEACHERS
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           kindergarten teacher is one of the fundamental pillars upon which the kindergarten environment so that exposure to a number of problems that could affect its functioning in addition to any deficiencies in this environment leads to deprive a child of some activities and acquisition of concepts so the researcher studying the problems of working in kindergartens from the perspective of the parameters, so the researcher based measuring instrument for labour problems of (30) search sample was paragraph (50) parameter that was chosen at random and have been extracted Sincerity and strength tool researcher used statistical methods and discriminatory (Pearson correlation coefficient, t

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Publication Date
Fri Mar 31 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
The Chages in Sex Hormones in Female Working in Battries Manufacturing Plant
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Lead has toxic effects on reproduction of both male and female.  It can cause decreased sex drive ,  infertility and abnormal menstrual cycle  in women.  This study was designed to evaluate the effect of exposure to lead in batteries female workers on sex hormones level in the serum.Thirty nine (39) female workers (volunteers) in Iraqi Batteries Manufacturing Plants, Al-Waziriya / Baghdad  were participated in this study. They are classified into 3 groups,  first group included fourteen (14) female that  have been employed for 1-7 years ,  second  group  included thirteen (13) female that have been employed for 8-14 years , third  grou

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Publication Date
Tue Nov 01 2022
Journal Name
Journal Of Engineering
Study The Impact of Geopolymer Mortar Reinforced by Micro Steel Fibers
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In this research, geopolymer mortar had to be designed with 50% to 50% slag and fly ash with and without 1% micro steel fiber at curing temperature of 240℃. The molarity of alkaline solution adjusted with 12 molar sodium hydroxid to sodium silicate was 2 to 1, reaspectivly. The heat of curing increased the geopolymerization proceses of geoplymer mortar, which led to increasing strength, giving the best result and early curing age. The heat was applied for two days by four hours each day. It was discovered in the impact test that the value first crack of each mix was somewhat similar, but the failure increased 72%  for the mixture that did not contain fiber. For the energy observation results it was shown that the mixt

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Publication Date
Mon Jan 16 2023
Journal Name
Journal Of Medical And Health Studies
Is Mometasone Effective in Treating Otitis Media with Effusion?
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Otitis media with effusion (OME) is the long-term deposition of mucus in the middle ear cleft. It is the leading cause of childhood hearing loss and a common childhood infection. It can impair communication and life quality. OME's direct and indirect costs are also crucial. Improving OME care is crucial. This study examines intranasal mometasone's efficacy in treating otitis media with effusion. A clinical trial study was conducted during a period from January 2021 to June 2022. It included 80 patients suffering from otitis media with effusion bilaterally (160 ears) who had an intact tympanic membrane and tympanometry type B. These patients were included only if they had a hearing change or loss noted by the parents or by the patien

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