Preferred Language
Articles
/
joe-600
Compensation of the Nonlinear Power Amplifier by Using SCPWL Predistorter with Genetic Algorithm in OFDM technique
...Show More Authors

The High Power Amplifiers (HPAs), which are used in wireless communication, are distinctly characterized by nonlinear properties. The linearity of the HPA can be accomplished by retreating an HPA to put it in a linear region on account of power performance loss. Meanwhile the Orthogonal Frequency Division Multiplex signal is very rough. Therefore, it will be required a large undo to the linear action area that leads to a vital loss in power efficiency. Thereby, back-off is not a positive solution. A Simplicial Canonical Piecewise-Linear (SCPWL) model based digital predistorters are widely employed to compensating the nonlinear distortion that introduced by a HPA component in OFDM technology. In this paper, the genetic algorithm has been used to optimized the SCPWL coefficients by using Matlab 2015b, and then the Bit Error Rate (BER) performance has been evaluated for OFDM signal with 16-QAM and 64-QAM modulations in three cases, with nonlinear effects, without nonlinear effects (ideal case), with SCPWL and with nonlinear effects (compensated case)). The simulation results showed that the predistorter that adjusted by the genetic algorithm accomplishes huge execution change by successfully compensating the nonlinearity and reducing the input and output back-off (IBO, OBO) of the HPA.

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed May 01 2019
Journal Name
Iraqi Journal Of Science
Investigation of nanostructured and gas sensing of tin dioxide films prepared by oxidation of Sn
...Show More Authors

Publication Date
Tue Jan 01 2008
Journal Name
J Bagh College Of Dentistry
Assessment of consistency and compressive strength of glass ionomer reinforced by different amount of hydroxyapatite
...Show More Authors

Background: Glass ionomers have good biocompatibility and the ability to adhere to both enamel and dentin. However, they have certain demerits, mainly low tensile and compressive strengths. Therefore, this study was done to assess consistency and compressive strength of glass ionomer reinforced by different amount of hydroxyapatite. Materials and Methods: In this study hydroxyapatite materials were added to glass ionomer cement at different ratios, 10%, 15%, 20%, 25% and 30% (by weight). The standard consistency test described in America dental association (ADA) specification No. 8 was used, so that all new base materials could be conveniently mixed and the results would be of comparable value and the compressive strength test described by

... Show More
View Publication Preview PDF
Publication Date
Wed May 01 2024
Journal Name
Journal Of Ecological Engineering
Explore the Impact of Surfactant Type on the Stability and Separation Efficiency of Oil–Water Emulsions of Real Wastewater from Al-Basrah Crude Oil Using Microbubble Air Flotation
...Show More Authors

Among several separation processes, the air flotation distinguish as remarkably high potential separation process related to its high separation efficiency and throughput, energy-efficient, simple process, cost-effective, applicable to a wide range of oily wastewater and no by-products. The current study aimed to investigate the effect of the type and concentration of surfactant on the stability of oil-water emulsion and efficiency of the separation process. For this purpose, three types of surfactant where used (anionic SDS, mixed nonionic Span 85/Tween 80, and cationic CTAB). The results demonstrated that the Span 85/Tween 80 surfactant has the best stability, and it increases with the surfactant concentration augmentation. The removal ef

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
BUMPINESS IN THE ATMOSPHERE IN IRAQ STUDY IN THE GEOGRAPHY OF CLIMATE
...Show More Authors

Bumpiness in the atmosphere is the vertical movement of air, whether
upward or downward movement and the bumpiness is accompanied by areas
of unrest in the air and wind. And contribute to each of the coups thermal
fronts, wind, wind and thunderstorms. Moreover, bumpiness is net of the
reasons that lead to circumstances is appropriate to cut the wind, and this
contributes to the formation of bumpiness in the atmosphere. The study found
that the noon of the times, which is expected to occur where clear-air
bumpiness during flights because of the warmth of the earth's surface. The
study found increased incidence of air hole during the summer, especially
July, due to increased incidence of coup surface, while the s

... Show More
View Publication Preview PDF
Publication Date
Fri Nov 01 2019
Journal Name
Journal Of Engineering
Analysis of Shell and Double Concentric Tube Heat Exchanger Using CFD Application
...Show More Authors

This study focuses on CFD analysis in the field of the shell and double concentric tube heat exchanger. A commercial CFD package was used to resolve the flow and temperature fields inside the shell and tubes of the heat exchanger used. Simulations by CFD are performed for the single shell and double concentric tube.

This heat exchanger included 16 tubes and 20 baffles. The shell had a length of 1.18 m and its diameter was 220 mm. Solid Works 2014, ANSYS 15.0 software was used to analyze the fields of flow and temperature inside the shell and the tubes. The RNG k-ε model was used and it provided good results. Coarse and fine meshes were investigated, showing that aspect ratio has no significant effect. 14 million

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Sun Mar 15 2020
Journal Name
Journal Of The College Of Education For Women
The Role of Supervisory and Training Practices in The Field Education Programmes in Achieving the Course Objectivesfrom the Perspective of the Student Teachers in the Faculty of Science and Arts in Sharourah
...Show More Authors

The present study aimed at identifying the role of supervisory and training practices in the field   education program in achieving course objectives from the perspective of the student teachers in the Faculty of Science and Arts in sharourah, and its relationship to some variables (gender, specialization,estimation). To achieve this, the researcher used the descriptive-analytical method, and the study tool was designed, which consists of (24) items distributed on two axes: the objectives of field education and supervisory and training practices.Then, the study tool was applied to the research sample represented in the entire study community, which consists of (65) male and female students in the Faculty of Sciences and Arts in

... Show More
View Publication Preview PDF
Publication Date
Sun Apr 28 2024
Journal Name
Bmc Medical Education
Pharmacy faculty experiences with student academic entitlement: a multinational study from the Arab world
...Show More Authors
Abstract<p>Academic Entitlement (AE) is the expectation by students to receive high grades or preferential treatment without significant effort. Exploring AE from faculty perspective has not been investigated in Arab colleges of pharmacy. The aim of this study was to explore experiences and perceptions towards student AE among pharmacy faculty in the Arab World. A cross-sectional, self-administered, anonymous, electronic survey was sent to pharmacy faculty across pharmacy colleges in Arab countries. The survey collected demographic data, an AE measure including 17 items reflecting seven AE components, and faculty perceptions and perceived reasons for AE. A total of 345 responses were collected. The AE level wa</p> ... Show More
View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Mon Mar 15 2021
Journal Name
Al-academy
tv series with multiple parts from the viewers viewpoint: عبد الكريم حسين عباس السوداني
...Show More Authors

TV drama has gone through many developmental stages until it reached and settled in the form of TV series of thirty episodes. Alongside the development of the TV technologies and the widespread of satellite channels, the form of the TV drama has changed and the series has consisted of two parts and then parts multiplied until they amounted to ten parts and more. This form of TV drama has become an artistic phenomenon, that once the series is displayed on one of the channels and achieves a noticeable success, its producers work to produce a second part of that series and so on. This form of TV drama has remained away from being researched.
This has urged the researcher to accomplish this study entitled (TV series of multiple parts fro

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 15 2020
Journal Name
Journal Of The College Of Education For Women
Second Language Learning and Its Relationship with the Third Language Learning: Statistical Study: China
...Show More Authors

The exchanges in various fields,like economics, science, culture, etc., have been enhanced unceasingly among different countries around the world in the twenty-first century, thus, the university graduate who masters one foreign language does not meet the need of the labor market in most countries.So, many universities began to develop new programs to cultivate students who can use more foreign languages to serve the intercultural communication. At the same time, there is more scientific research emerged which is related to the relationship between the second and third languages. This humble research seeks to explain the relevant concepts and analyze the real data collected from Shanghai International Studies University in China, to expl

... Show More
View Publication Preview PDF
Publication Date
Tue Jul 05 2022
Journal Name
Journal Of Pharmaceutical Care
Epidemiological and Clinical Factors Affecting the Response to Etanercept Among Patients with Rheumatoid Arthritis
...Show More Authors

View Publication Preview PDF
Crossref