Preferred Language
Articles
/
alkej-37
Performance Improvement of Neural Network Based RLS Channel Estimators in MIMO-OFDM Systems
...Show More Authors

The objective of this study was tointroduce a recursive least squares (RLS) parameter estimatorenhanced by using a neural network (NN) to facilitate the computing of a bit error rate (BER) (error reduction) during channels estimation of a multiple input-multiple output orthogonal frequency division multiplexing (MIMO-OFDM) system over a Rayleigh multipath fading channel.Recursive least square is an efficient approach to neural network training:first, the neural network estimator learns to adapt to the channel variations then it estimates the channel frequency response. Simulation results show that the proposed method has better performance compared to the conventional methods least square (LS) and the original RLS and it is more robust at high speed mobility.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Jan 01 2021
Journal Name
Computers, Materials & Continua
Fused and Modified Evolutionary Optimization of Multiple Intelligent Systems Using ANN, SVM approaches
...Show More Authors

View Publication
Scopus (6)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Sun Mar 02 2008
Journal Name
Baghdad Science Journal
Calculations of Signal to Noise Ratio (SNR) for Free Space Optical Communication Systems
...Show More Authors

In this paper, we calculate and measure the SNR theoretically and experimental for digital full duplex optical communication systems for different ranges in free space, the system consists of transmitter and receiver in each side. The semiconductor laser (pointer) was used as a carrier wave in free space with the specification is 5mW power and 650nm wavelength. The type of optical detector was used a PIN with area 1mm2 and responsively 0.4A/W for this wavelength. The results show a high quality optical communication system for different range from (300-1300)m with different bit rat (60-140)kbit/sec is achieved with best values of the signal to noise ratio (SNR).

View Publication Preview PDF
Crossref
Publication Date
Mon Dec 05 2022
Journal Name
Baghdad Science Journal
An Asymptotic Analysis of the Gradient Remediability Problem for Disturbed Distributed Linear Systems
...Show More Authors

The goal of this work is demonstrating, through the gradient observation of a   of type linear ( -systems), the possibility for reducing the effect of any disturbances (pollution, radiation, infection, etc.) asymptotically, by a suitable choice of related actuators of these systems. Thus, a class of  ( -system) was developed based on finite time  ( -system). Furthermore, definitions and some properties of this concept -system and asymptotically gradient controllable system ( -controllable) were stated and studied. More precisely, asymptotically gradient efficient actuators ensuring the weak asymptotically gradient compensation system ( -system) of known or unknown disturbances are examined. Consequently, under convenient hypo

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (4)
Scopus Crossref
Publication Date
Sun Mar 15 2020
Journal Name
Al-academy
Techniques of Acting Performance in Fantasy Theatrical Show: راسل كاظم عوده-ليلى فؤاد فاضل
...Show More Authors

     This research deals with the fact that arts exit from their familiar context in practice and enter in the context of the fantasy and exoticism picture. In order to understand the theatrical phenomenon and know the way of its production of the fantasy picture, especially the acting performance in its transitions between the real and fantasy. This study consists of: an introduction of the research in which the researcher presented the research problem, importance and objectives.  

    The theoretical framework dealt with founding a theoretical part for the research consisting of two sections: the first (fantasy: the concept and the working) and the second (techniques of acting perfo

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon May 27 2019
Journal Name
Al-academy
The Performance Variable of the Actor's Techniques in Postmodern Theater Shows: وئام وافي علي
...Show More Authors

The postmodern ideas and concepts have produced social, political and economic variables that have been affected by wars, crises, the role of globalization and the information revolution. They have created many variables in concepts and great variables in technological, artistic and cultural innovations. All these changes have contributed to changing the form of the theatrical show aesthetically and intellectually, which cast a shadow over the nature of the actor's performance who has become more demanding to change his performance and to find the mechanisms and new nature of work governing him corresponding to those variables and this prompted the researcher to adopt the subject (the performance variable of the actor's techniques in pos

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 17 2019
Journal Name
Baghdad Science Journal
A Study on the Accuracy of Prediction in Recommendation System Based on Similarity Measures
...Show More Authors

Recommender Systems are tools to understand the huge amount of data available in the internet world. Collaborative filtering (CF) is one of the most knowledge discovery methods used positively in recommendation system. Memory collaborative filtering emphasizes on using facts about present users to predict new things for the target user. Similarity measures are the core operations in collaborative filtering and the prediction accuracy is mostly dependent on similarity calculations. In this study, a combination of weighted parameters and traditional similarity measures are conducted to calculate relationship among users over Movie Lens data set rating matrix. The advantages and disadvantages of each measure are spotted. From the study, a n

... Show More
View Publication Preview PDF
Scopus (17)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Wed Mar 01 2023
Journal Name
مجلة كلية العلوم الاسلامية / جامعة بغداد
توظيف التعلم الالكتروني باستعمال الوسائل التكنلوجية في العملية التعليمية واهميته في نحقيق التنمية المستدامة
...Show More Authors

Preview PDF
Publication Date
Tue Mar 31 2015
Journal Name
Al-khwarizmi Engineering Journal
Dual Measurements of Pressure and Temperature With Fiber Bragg Grating Sensor
...Show More Authors

Abstract

The fiber Bragg grating (FBG) technology has been rapidly applied in the sensing technology field. In this work, uniform FBG was used as pressure sensor based on measuring related Bragg wavelength shift. The pressure was applied directly by air compressor to the sensor and the pressure was ranged from 1 to 6 bar.

      This sensor also was affected by the external temperature so as a result it could be used as a temperature sensor. This sensor could be used to monitor the pressure of dams. It has been shown from the result that the sensor is very sensitive to the pressure and the sensitivity was (67 pm\bar) and is very sensitive to temperature and the sensitivity was (10p

... Show More
View Publication Preview PDF
Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
تقويم كفاءة أداء الاستثمارات بحث تطبيقي في شركتي التأمين الوطنية والتأمين العراقية
...Show More Authors

This study attempts to highlights on the evaluation of performance efficiency for Investments in both National & Iraqi Insurance companies for the years 2001-2010 and their importance on those companies and the economy of the country in order to find  out the investment areas and to compare between investment activity and its revenues as well as to compare performance of both companies in investment field.

The study was based on annual reports and balance sheets of both companies. In many chapters, this study dealt with theoretical and practical aspects of the investments and its revenues. Key hypothesis was based on this study, including four parts of Sub hypotheses about (statistical effective relationship between the

... Show More
View Publication Preview PDF
Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Choosing the best method for estimating the survival function of inverse Gompertz distribution by using Integral mean squares error (IMSE)
...Show More Authors

In this research , we study the inverse Gompertz distribution (IG) and estimate the  survival function of the distribution , and the survival function was evaluated using three methods (the Maximum likelihood, least squares, and percentiles estimators) and choosing the best method estimation ,as it was found that the best method for estimating the survival function is the squares-least method because it has the lowest IMSE and for all sample sizes

View Publication Preview PDF
Crossref