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ijs-10688
Designing Cassegrain Telescope System with Best Obscuration Ratio of Secondary Mirror
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     A computer simulation was conducted using Optics Software for Layout and Optimization (OSLO) to design a Cassegrain telescope system for on-axis rays. In order to establish such a telescope, the two mirrors of the optical system were designed as spherical surfaces: a concave mirror and a convex mirror. The obscuration ratios of the Cassegrain telescope's secondary mirror were examined using different values, which ranged between 0.1 and 0.3, to determine the best obscuration ratio. This work adopted three criteria to decide which obscuration ratio is the best for the Cassegrain telescope. The first criterion was the number of rays that reached the final image. The second criterion was calculating the modulation transfer function (MTF). The third criterion was calculating the point spread function (PSF) and Strehl ratio (SR). Finally, the result showed that the best obscuration ratio of the telescope’s secondary mirror was found at D2/D1=0.116-0.166, where D1=0.76 m for the primary mirror and D2=0.09 – 0.125m for the secondary mirror.

 

 

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Publication Date
Mon Apr 10 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Simulation of Multilayer Mirror Design for Visible region Using MATLAB Language
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  In this work, the theoretical study for designing of dielectric mirrors of high reflectance in the visible region of electromagnetic spectrum between wavelength of 400-700 nm is presented, and searching on the performance properties of the design, like there reflectance as a function to the wavelength, as beam incident in a normal form, for the materials of neglected absorbance, and scattering, in the form of thin film deposition, which are deposited on glass substrate, and by using matrix system in the study, which are used as computer simulation in MATLAB code.      The materials which are used in this study are represented by ( AlAs ), (TiO2 ),( SiC ), and  (Si3N4 ), which used in the designing mirrors alter

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Publication Date
Mon Aug 26 2019
Journal Name
Iraqi Journal Of Science
Finding Best Clustering For Big Networks with Minimum Objective Function by Using Probabilistic Tabu Search
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     Fuzzy C-means (FCM) is a clustering method used for collecting similar data elements within the group according to specific measurements. Tabu is a heuristic algorithm. In this paper, Probabilistic Tabu Search for FCM implemented to find a global clustering based on the minimum value of the Fuzzy objective function. The experiments designed for different networks, and cluster’s number the results show the best performance based on the comparison that is done between the values of the objective function in the case of using standard FCM and Tabu-FCM, for the average of ten runs.

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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Numerical Study of Optimum Configuration of Unconventional Airfoil with Steps and Rotating Cylinder for Best Aerodynamics Performance
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Numerical study of separation control on symmetrical airfoil, four digits (NACA

0012) by using rotating cylinder with double steps on its upper surface based on the computation of Reynolds-average Navier- Stokes equations was carried out to find the optimum configuration of unconventional airfoil for best aerodynamics performance. A model based on collocated Finite Volume Method was developed to solve the governing equations on a body-fitted coordinate system. A revised (k-w) model was proposed as a known turbulence model. This model was adapted to simulate the control effects of rotating cylinder. Numerical solutions were performed for flow around unconventional airfoil with cylinder to main stream velocities ratio in the range

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Publication Date
Mon Apr 03 2023
Journal Name
Journal Of Educational And Psychological Researches
Personal and Moral Responsibility and Its Relation with Moral Flexibility upon Faculty of Secondary Schools
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Abstract

The factor that keeps society from collapsing and regressing to chaos, violence, and lawbreaking is to stick to the human moral principles and criteria of moral behavior that prevent the spread of corruption and crime to the extent that law becomes devoid of activity and loss its dot errant power in front of chaos. The role of moral behavior is to motivate individuals to respect the general laws in dealing with others. Because of the dissemination of odd behavior patterns within our society, the social links are been badly affected and it's urgent for educational institutions to perform their duty in working on spreading awareness about moral values and avoid deviant directions and socially threatening t

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Publication Date
Thu Apr 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Designing an electronic program for the Assessment of project management in accordance with the methodology (PMBOK)
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The research aims to design an electronic program that allows users to assess the possibility of different practices for projects management professional according to the PMBOK methodology)) and using the requirements Data mentioned in the "knowledge and experience in project management Evaluation guide" issued by the professional Institute of project management According to the results of this program will be electronic The possible classification of project management in terms of both (proficiency_ perform tasks) as less than the desired level or within or above average in terms of best practices, and finally a number of recommendations to overcome the possible shortcomings. The most important is the need to enrich the service

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Publication Date
Mon Jan 29 2024
Journal Name
Proceedings Of The International Conference On Research Advances In Engineering And Technology - Itechcet 2022
Effect of length to diameter ratio on column bearing capacity stabilized with sodium silicate
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The numerical analysis was conducted to studying the influence of length to diameter ratio (L/D) on the behavior of the soil treated with sand columns treated with 8% sodium silicate for both floating and end bearing type by using finite element method (Plaxis 3D Foundation ) for isolated foundation of real dimensions. The analysis’s study indicate that in the floating type the best improvement ratio was achieved at (L/D=8) when using columns with a diameter of (0.5, 0.7), but when using columns with a diameter of 0.3 m, it was noticed that the bearing improvement ratio increases with increasing (L/d). While the results of the analysis for end bearing type show that the higher improvement ratio was achieved at (L/D=4) when using columns w

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Publication Date
Fri May 01 2015
Journal Name
Journal Of Physics: Conference Series
Spectrum of Secondary Submodules
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Publication Date
Thu Apr 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
A Novel Algorithm to Find the Best Solution for Pentagonal Fuzzy Numbers with Linear Programming Problems
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    Fuzzy numbers are used in various fields such as fuzzy process methods, decision control theory, problems involving decision making, and systematic reasoning. Fuzzy systems, including fuzzy set theory. In this paper, pentagonal fuzzy variables (PFV) are used to formulate linear programming problems (LPP). Here, we will concentrate on an approach to addressing these issues that uses the simplex technique (SM). Linear programming problems (LPP) and linear programming problems (LPP) with pentagonal fuzzy numbers (PFN) are the two basic categories into which we divide these issues. The focus of this paper is to find the optimal solution (OS) for LPP with PFN on the objective function (OF) and right-hand side. New ranking f

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Publication Date
Fri Mar 29 2024
Journal Name
Iraqi Journal Of Science
Finding the Best Route for Connecting Citizens with Service Centers in Baghdad Based on NN Technology
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     A geographic information system (GIS) is a very effective management and analysis tool. Geographic locations rely on data. The use of artificial neural networks (ANNs) for the interpretation of natural resource data has been shown to be beneficial. Back-propagation neural networks are one of the most widespread and prevalent designs. The combination of geographic information systems with artificial neural networks provides a method for decreasing the cost of landscape change studies by shortening the time required to evaluate data. Numerous designs and kinds of ANNs have been created; the majority of them are PC-based service domains. Using the ArcGIS Network Analyst add-on, you can locate service regions around any network

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Publication Date
Tue Jan 02 2018
Journal Name
Journal Of Educational And Psychological Researches
Masculine identification among secondary schoolboys
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The purposes of this study are to measure masculine's identification among secondary school students, and to examine the significant differences among secondary school students in respect of students age (16-18) year. The researcher has prepared a questionnaire comprised (25) item to measure masculine identification among students: this scale was applied on (100) student who were selected as a sample from four different school at al-rusafa side in Baghdad. The scale then modified to (23) item to be more consistent. The results revealed that there were no significant differences among students based on the variable of age, and the mean of masculine identification showed a high level than the hypothesized mean.

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