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Variable Structure Control Design for a Magnetic Levitation System
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In this paper the variable structure control theory is utilized to derive a discontinuous controller to the magnetic levitation system. The magnetic levitation system model is considered uncertain, which subjected to the uncertainty in system parameters, also it is open-loop unstable and strongly nonlinear. The proposed variable structure control to magnetic levitation system is proved, and the area of attraction is determined. Additionally, the chattering, which induced due to the discontinuity in control law, is attenuated by using a non-smooth approximate. With this approximation the resulted controller is a continuous variable structure controller with a determined steady state error according to the selected control parameters. Finally the ability and the effectiveness of the proposed continuous variable structure controller to the magnetic levitation system are verified via numerical simulations. When state initiated inside the area of attraction, the results show that the ball position can be directed to follow various desired positions, with steady state error not exceeding .  

 

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Publication Date
Mon Apr 14 2014
Journal Name
Ibn Al-haitham Jour. For Pure & Appl. Sci
Synthesis and Characterization of Some O-[2-{''2-Substituted Aryl (''1,''3,''4 thiadiazolyl) ['3,'4-b]-'1,'2,'4- Triazolyl]-Ethyl]-p- chlorobenzald oxime Derivatives
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In this study new derivatives of O-[2-{''2-Substituted Aryl (''1,''3,''4 thiadiazolyl) ['3,'4-b]-'1,'2,'4- Triazolyl]-Ethyl]-p- chlorobenzald oxime (6-11)have been synthesized from the starting material p-chloro – E- benzaldoxime 1.Compound 2 was synthesized by the reaction of p-chloro – E- benzaldoxime with ethyl acrylate in basic medium. Refluxing compound 2 with hydrazine hydrate in ethanol absolute afforded 3. Derivative 4 was prepared by the reaction of 3 with carbon disulphide, treated of compound 4 with hydrazine hydrate gave 5. The derivatives (6-11) were prepared by the reaction of 5 with different substitutesof aromatic acids. The structures of these compounds were characterized from their melting points, infrared spectroscopy

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Publication Date
Thu Apr 25 2019
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
HARNESSING DIGITIZATION TO ACHIEVE THE GOALS OF SUSTAINABLE DEVELOPMENT 2030\ EXPERIENCE OF THE EMIRATE OF DUBAI.: HARNESSING DIGITIZATION TO ACHIEVE THE GOALS OF SUSTAINABLE DEVELOPMENT 2030\ EXPERIENCE OF THE EMIRATE OF DUBAI.
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Experienced economic environmentRadical changes at the end of the last century and the beginning of the present century, resulting in new concepts and expectations in all aspects of economic, political, social and even behavioral.Each of these concepts is the result of rapid developments in the intangible space. Competition is no longer limited to the mere possession of tangible material resources, but because of its link to knowledge and technology content and to the comprehensive quality standards and efficient and effective policies of States. With the increasing pace of growth and interdependence among the global economies, this resulted in the birth of a new economic system led by technological development and financial liberalizati

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Publication Date
Wed Mar 30 2022
Journal Name
Journal Of Educational And Psychological Researches
Extension of sense of self According to Cognitive style Of Complexity-Simplicity Among University Students
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The current research aims to identify the level of extension of the sense of self and the cognitive style (complexity - simplification) among university students, as well as the significance of the difference according to gender (males - females), as well as the correlation between the two variables, and in order to verify this, the researcher has constructed The measure of the extension of the sense of self based on the theory of Alport 1961, as the number of its final paragraphs reached (28) paragraphs, and the cognitive style scale (complexity - simplification) prepared by (Abdullah 2017) was adopted, as the scale consisted of (32) paragraphs in its final form. To verify their psychometric properties, and the two tools were applied to

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Publication Date
Tue Feb 14 2023
Journal Name
Journal Of Educational And Psychological Researches
The Organizational Relaxation of Employees of the Educational Directorates in the Sultanate of Oman
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Abstract

The current research aims to identify the level of organizational relaxation among the employees of educational directorates in the Sultanate of Oman. The descriptive approach was used, as well as a questionnaire of two parts to collect data. The questionnaire consists of (15) items divided into three themes about the relaxing level. It was applied on a sample of (406) male & female employees of the educational directorates who were randomly selected. The results of the study showed that the level of organizational relaxation was low. The study results also found that there were no statistically significant differences at the level of significance (α ≤ 0.05) of the study sample in the level of org

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Publication Date
Thu Dec 01 2016
Journal Name
Journal Of Engineering
Numerical and Experimental Investigations of the Effect of PVD and Vacuum Pressure on the Degree of Saturation
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    Soft clays are generally characterized by low shear strength, low permeability and high compressibility. An effective method to accelerate consolidation of such soils is to use vertical drains along with vacuum preloading to encourage radial flow of water.  In this research numerical modeling of prefabricated vertical drains with vacuum pressure was done to investigate the effect of using vertical drains together with vacuum pressure on the degree of saturation of fully and saturated-unsaturated soft soils.  Laboratory experiments were conducted by using a specially-designed large consolidometer cell where a central drain was installed and vacuum pressure was applied. All tests were conducted

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Publication Date
Sun Sep 05 2010
Journal Name
Baghdad Science Journal
Synthesis and Characterization of New Metal Complexes of α-Aminonitriles Derived from P- Toluidine and Aromatic Aldehydes
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New metal complexes of some transition metal ions Co(II), Cu(II) , Cd(II) and Zn(II) were prepared by their reaction with previously prepared ligands HLI= (P-methyl anilino) phenyl acetonitrile and HLII = (P-methyl anilino) –P– chloro phenyl acetonitrile . The two ligands were prepared by Strecker’s procedure which includ the reaction of p- toluidine with benzaldehyde and P- chlorobenzaldehyde respectively. Structures were proposed depending on atomic absorption , i.r. and u.v.visible spectra in addition to magnetic susceptibility and electrical conductivity measurements.

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Publication Date
Thu Oct 01 2009
Journal Name
Iraqi Journal Of Physics
تقنیة جدیدة لدراسة انتقال الطاقة الجانبیة
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The transport of energy from the focal region when high power laser are focused onto
solid targets is of two dimensions axially in the direction of the laser and laterally in the
direction along the target surface perpendicular to the laser direction.
In this paper we present anew consideration to study lateral energy transport in plasma
produced by laser KrF λ=248nm and pulse time 20n sec. Targets are C, Al, Cu.we used
photo resist (negative type) which is mode localy and noticing the effective area as
afunction of lateralenergy transport

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Publication Date
Wed Dec 12 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Stress and Its Associated Factors among Students of the College of Nursing University of Baghdad
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Objectives: The current study aims at identifying the level of perceived stress among nursing college students and determining the factors associated with stress they have. Methodology: A cross-sectional descriptive study initiated for the period on November 1st, 2014 to May 1st, 2015. The study has been conducted on the undergraduate nursing college students / University of Baghdad. The sample of the study was consisted of (128) students who were selected purposively. The questionnaire of the study was adopted and modified for the present study which consisted of socio-demographic data and the scale of

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Publication Date
Sun Apr 04 2010
Journal Name
Journal Of Educational And Psychological Researches
Effective an instructional in program in the development of some of the moral values on the children of kindergarten
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The research aims to
1 – The discloser  of the level of moral values in the children of
kindergarten.
2 - Building an educational program designed to develop moral values on the children of
kindergarten.

3 - Knowing the impact of the program in the development of moral values in children
Purposive sample was selected consisted of 40 children and a child aged 5-6 years and to achieve objectives of the research promising measure of the moral  values
kindergarten has been applied to the children of the two groups was based on  pre and post test

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Publication Date
Thu Sep 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
The influence of the personal values of the workers in the performance of the work teams
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The research aims to know the impact of workers values on their performance which is reflected on increasing productivity and improving its quality as well as the organization's progress and success.  Application of this research took place in the General Company Of Electrical Industries; it contained four main pillars; the first involved research methodology، regarding the problem، importance، aim، basic theory، and method of data collection، the second is dedicated to the theoretical framework related to the research basic variables (values and workgroups) the third is assigned to analyze the actual data by using number of statistical methods، such as mathematical medium and standard deviation and also spearman rank

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