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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
Fri Mar 31 2017
Journal Name
Al-khwarizmi Engineering Journal
Design an Integral Sliding Mode Controller for a Nonlinear System
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The goal of this paper is to design a robust controller for controlling a pendulum
system. The control of nonlinear systems is a common problem that is facing the researchers in control systems design. The Sliding Mode Controller (SMC) is the best solution for controlling a nonlinear system. The classical SMC consists from two phases. The first phase is the reaching phase and the second is the sliding phase. The SMC suffers from the chattering phenomenon which is considered as a severe problem and undesirable property. It is a zigzag motion along the switching surface. In this paper, the chattering is reduced by using a saturation function instead of sign function. In spite of SMC is a good method for controlling a nonlinear system b

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Publication Date
Wed Jul 29 2020
Journal Name
Iraqi Journal Of Science
Dual-Stage Social Friend Recommendation System Based on User Interests
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The use of online social network (OSN) has become essential to humans' lives whether for entertainment, business or shopping. This increasing use of OSN motivates designing and implementing special systems that use OSN users' data to provide better user experience using machine learning and data mining algorithms and techniques. One system that is used extensively for this purpose is friend recommendation system (FRS) in which it recommends users to other users in professional or entertaining online social networks.

For this purpose, this study proposes a novel friend recommendation system, namely Hybrid Friend Recommendation (FR) model. The Hybrid model applies dual-stage methodology on unlabeled data of 1241 users collected fro

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Publication Date
Sun Jan 30 2022
Journal Name
Iraqi Journal Of Science
A New Image Encryption Algorithm Based on Multi Chaotic System
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       In recent years, encryption technology has been developed rapidly and many image encryption methods have been put forward. The chaos-based image encryption technique is a modern encryption system for images. To encrypt images, it uses random sequence chaos, which is an efficient way to solve the intractable problem of simple and highly protected image encryption. There are, however, some shortcomings in the technique of chaos-based image encryption, such limited accuracy issue. The approach focused on the chaotic system in this paper is to construct a dynamic IP permutation and S-Box substitution by following steps. First of all, use of a new IP table for more diffusion of al

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Publication Date
Tue Jan 17 2023
Journal Name
International Journal Of Online And Biomedical Engineering (ijoe)
Private Backend Server Software-Based Telehealthcare Tracking and Monitoring System
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In these recent years, the world has witnessed a kind of social exclusion and the inability to communicate directly due to the Corona Virus Covid 19 (COVID-19) pandemic, and the consequent difficulty of communicating with patients with hospitals led to the need to use modern technology to solve and facilitate the problem of people communicating with each other. healthcare has made many remarkable developments through the Internet of things (IOT) and cloud computing to monitor real-time patients' data, which has enabled many patients' lives to be saved. this paper presents the design and implementation of a Private Backend Server Software based on an IoT health monitoring system concerned emergency medical services utilizing biosenso

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Publication Date
Fri Jan 01 2021
Journal Name
International Journal Of Drug Delivery Technology
Transethosomes a novel transdermal drug delivery system for antifungal drugs
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Publication Date
Tue Jun 30 2015
Journal Name
Al-khwarizmi Engineering Journal
Integral Sliding Mode Control Design for Electronic Throttle Valve System
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Abstract

 One of the major components in an automobile engine is the throttle valve part. It is used to keep up with emissions and fuel efficiency low. Design a control system to the throttle valve is newly common requirement trend in automotive technology. The non-smoothness nonlinearity in throttle valve model are due to the friction model and the nonlinear spring, the uncertainty in system parameters and non-satisfying the matching condition are the main obstacles when designing a throttle plate controller.

In this work, the theory of the Integral Sliding Mode Control (ISMC) is utilized to design a robust controller for the Electronic Throttle Valve (ETV) system. From the first in

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Publication Date
Wed Feb 29 2012
Journal Name
Al-khwarizmi Engineering Journal
A New Audio Steganography System Based on Auto-Key Generator
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Stenography is the art of hiding the very presence of communication by embedding secret message into innocuous looking cover document, such as digital image, videos, sound files, and other computer files that contain perceptually irrelevant or redundant information as covers or carriers to hide secret messages.

In this paper, a new Least Significant Bit (LSB) nonsequential embedding technique in wave audio files is introduced. To support the immunity of proposed hiding system, and in order to recover some weak aspect inherent with the pure implementation of stego-systems, some auxiliary processes were suggested and investigated including the use of hidden text jumping process and stream ciphering algorithm. Besides, the suggested

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Publication Date
Thu Apr 28 2022
Journal Name
Iraqi Journal Of Science
Robotic System for Tracking Moving Objects Based On Their Color
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Tracking moving objects is one of a very important applications within the computer vision. The goal of object tracking is segmenting a region of interest from a video scene and keeping track of its motion and positioning. Track moving objects used in many applications such as video surveillance, robot vision, and traffic monitoring, and animation. In this paper a four-wheeled robotic system have been designed and implemented by using Arduino-Uno microcontroller. Also a useful algorithms have been developed to detect and track objects in real time. The main proposed algorithm based on the kernel based color algorithm and some geometric properties to tracking color object. Robotic system is a compromise of two principal parts which are th

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Physics: Conference Series
Determination of the Fertility of Southern Iraqi Soil Using Laser - Induced Breakdown Spectroscopy System
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In this work, seven soil samples were brought brought to study and analyses the element concentrations from different southern regions of Iraq using laser-induced breakdown spectroscopy (LIBS) technique. It has been documented as an atomic emission spectroscopy (AES) technique. Laser-induced plasma utilized to analyze elements in materials (gases, liquids, and solids). In order to analyze elements in materials (gases, liquids, and solid). The Nd: YAG laser excitation source at 1064 nm with pulse width 9 ns is used to generate power density of 5.5 x 1012 MW/mm2, with optical spectrum in the range 320-740 nm. From this investigation, the soil sample analysis of the southern cities of Iraqi, it is concluded that the rich soil element of P, Si,

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Publication Date
Sun May 14 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Calculate of the Rate Constant of Electron Transfer in TiO2 – Safranine Dye System
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         A theoretical calculations of the rate constant of electron transfer (ET) in a dye – semiconductor system with variety solvent are applied on system contains safranineT dye with TiO2 in many solvents like water, 1-propanol, Formamide, Acetonitrile and Ethanol.

    A matlap program has been written to evaluate many parameters such that, the solvent reorganization energy, effective free energy, activation free energy, coupling matrix element and the rate constant of electron transfer.

    The results of the rate constant of electron transfer calculated theoretically are in a good agreement with experimental and theoretical value

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