Preferred Language
Articles
/
jih-2857
Simulation and Evaluation of a Variable Effective Focal Length of Refractive Binocular Telescope
...Show More Authors

The telescope works to magnify images of distant objects in general, but it needs special optical elements to complete the task to the fullest. The telescope needs optimal balance values of the optical parameters used to produce the best image, such as the effective focal length and the diameter of the pupil aperture, which are combined in a single concept called the focal number. The ground-based binary telescope relies on special lenses and an exceptional prism to achieve a hybrid design that produces clear images of relatively distant terrestrial objects. The pupil diameter of the telescope is relatively large to ensure that the largest possible amount of light is received, and as a result, a good image is obtained.

In this work, an achromatic objective lens and a Porro prism has been used to reduce the length of the telescope and change the path of the rays to the eyepiece, in addition to the presence of a flat convex lens behind the prism to collect the rays coming from it to reach the eyepiece. The effective focal length of the optical system was changed to illustrate the effect of this factor on the performance of a telescope and as a result of its effect on the image quality.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Simulation and experimental study of Pin-Plate DC discharge plasma technique
...Show More Authors

The present work intends to study of dc glow discharge were generated between pin (cathode) and a plate (anode) in Ar gas is performed using COMSOL were used to study electric field distribution along the axis of the discharge and also the distribution of electron density and electron temperature at constant pressure (P=.0.0mbar) and inter electrode distance (d=4 cm) at different applied voltage for both pin cathode system and plate anode and comparison with experimental results.

View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Tue Dec 26 2017
Journal Name
Al-khwarizmi Engineering Journal
Simulation Recording of an ECG, PCG, and PPG for Feature Extractions
...Show More Authors

Recently, the development of the field of biomedical engineering has led to a renewed interest in detection of several events. In this paper a new approach used to detect specific parameter and relations between three biomedical signals that used in clinical diagnosis. These include the phonocardiography (PCG), electrocardiography (ECG) and photoplethysmography (PPG) or sometimes it called the carotid pulse related to the position of electrode.

Comparisons between three cases (two normal cases and one abnormal case) are used to indicate the delay that may occurred due to the deficiency of the cardiac muscle or valve in an abnormal case.

The results shown that S1 and S2, first and second sound of the

... Show More
View Publication Preview PDF
Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of Partial Least Squares and Principal Components Methods by Simulation
...Show More Authors

Abstract                                                                                              

The methods of the Principal Components and Partial Least Squares can be regard very important methods  in the regression analysis, whe

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of Poisson Regression and Conway Maxwell Poisson Models Using Simulation
...Show More Authors

Regression models are one of the most important models used in modern studies, especially research and health studies because of the important results they achieve. Two regression models were used: Poisson Regression Model and Conway-Max Well-  Poisson), where this study aimed to make a comparison between the two models and choose the best one between them using the simulation method and at different sample sizes (n = 25,50,100) and with repetitions (r = 1000). The Matlab program was adopted.) to conduct a simulation experiment, where the results showed the superiority of the Poisson model through the mean square error criterion (MSE) and also through the Akaiki criterion (AIC) for the same distribution.

Paper type:

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Mar 01 2016
Journal Name
Journal Of Engineering
Design and Simulation of Sliding Mode Fuzzy Controller for Nonlinear System
...Show More Authors

Sliding Mode Controller (SMC) is a simple method and powerful technique to design a robust controller for nonlinear systems. It is an effective tool with acceptable performance. The major drawback is a classical Sliding Mode controller suffers from the chattering phenomenon which causes undesirable zigzag motion along the sliding surface. To overcome the snag of this classical approach, many methods were proposed and implemented. In this work, a Fuzzy controller was added to classical Sliding Mode controller in order to reduce the impact chattering problem. The new structure is called Sliding Mode Fuzzy controller (SMFC) which will also improve the properties and performance of the classical Sliding Mode control

... Show More
View Publication Preview PDF
Publication Date
Mon Sep 30 2002
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Modeling and Simulation of the Boilers at Al-Mussaib Thermal Station
...Show More Authors

View Publication Preview PDF
Publication Date
Wed Oct 20 2010
Journal Name
The International Journal Of Advanced Manufacturing Technology
Finite element modeling and simulation of proposed design magneto-rheological valve
...Show More Authors

Magneto-rheological (MR) valve is one of the devices generally used to control the speed of Hydraulic actuator of MR fluid. The performance of valve depends on the magnetic circuit design. Present study deals with a new design of MR valve. A mathematical model for the MR valve is developed and the simulation is carried out to evaluate the newly developed MR valve. The design of the magnetic circuit is accomplished by magnetic finite element software such as Finite Element Method Magnetic (FEMMR). The model dimensions of MR valve, material properties are taken into account. The results of analysis are presented in terms of magnetic strength H and magnetic flux density B. The simulation results based on the proposed model indicate that the ef

... Show More
View Publication
Scopus (36)
Crossref (29)
Scopus Clarivate Crossref
Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Simulation of Heat Storage and Heat Regeneration in Phase Change Material
...Show More Authors

The present study explores numerically the energy storage and energy regeneration during Melting and Solidification processes in Phase Change Materials (PCM) used in Latent Heat Thermal Energy Storage (LHTES) systems. Transient two-dimensional (2-D) conduction heat transfer equations with phase change have been solved utilizing the Explicit Finite Difference Method (FDM) and Grid Generation technique. A Fortran computer program was built to solve the problem. The study included four different Paraffin's. The effects of container geometrical shape, which included cylindrical and square sections of the same volume and heat transfer area, the container volume or mass of PCM, variation of mass flow rate of heat transfer fluid (HTF), and temp

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Sat Dec 17 2022
Journal Name
Journal Of Al-ma'moon College
Simulation and Implementation of SNR Measurement processor for Adaptive Communication Systems
...Show More Authors

Preview PDF
Publication Date
Sun Mar 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Simulation of five methods for parameter estimation and functionExponential distribution reliability
...Show More Authors
The estimation process is one of the pillars of the statistical inference process as well as the hypothesis test, and the assessment is based on the collection of information and conclusions about the teacher or the community's teachers on the basis of the result
... Show More
View Publication Preview PDF
Crossref