Preferred Language
Articles
/
alkej-132
Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
...Show More Authors

Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at high Doppler shifts with same SNR and target BER=10-4. It was shown that the performance at higher Doppler frequency shifts (<30Hz) was improved by more than 2dB over channel estimation at target BER=10-4 and 32QAM constellation used.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Dec 06 2015
Journal Name
Baghdad Science Journal
Synthesis, Characterization and Antibacterial of 2,3-Dihydrobenzo Thiazole-2-Carboxylic Acid Complexes with Some Selected Metal Ions
...Show More Authors

A new ligand 2,3-dihydrobenzo [d] thiazole-2-carboxylic acid (L) has been prepared from the reaction of ortho amino phenyl thiol with dichloroacetic acid in mole ratio (1:1). It has been characterized by elemental analysis (C.H.N.), IR, UV- Vis.spectraand 1H, 13C-NMR. A new series complexes of the bivalent ions (Co, Ni, Cu, Pd, Cd, Hg and Pb) and the trivalent (Cr) have been prepared and characterized too. The structural has been established by elemental analysis (C.H.N.), IR, UV-Vis. spectra, molar conductivity, atomic absorption and magnetic susceptibility measurements. The synthesized complexes were prepared in (1:2) ratio correspond to (Co(II), Ni(II), Cu(II), Pd(II), Cd(II), Hg(II) and Pb(II) complexes while in case Cr(III) complex is

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 14 2023
Journal Name
Al-academy
Social Graphic Design and its Reflections on The Practices of The Saudi Designer in Designing Awareness Posters
...Show More Authors

The concept of social graphic design is one of the most critical areas that highlight the designer's knowledge of social responsibility by employing design skills in community awareness. This study focused on defining social graphic design, the meaning, practices, and strategies for designing awareness posters. This study reviewed two examples of awareness posters that reflect the Saudi designer's practices. The results summarized that social graphic design is a concept not taught directly but gained from permanent practice in designing awareness posters that interact with community issues. The designer's understanding of his social events and their sensing in the visual form of a poster reflects the designer's social awareness. Social g

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Nov 24 2023
Journal Name
Iraqi Journal Of Science
Atmospheric Stability and Its Effect on The Polluted Columns of Concentrations in North West of Baghdad City
...Show More Authors

Atmospheric stability plays the most important role in the transport and dispersion of air pollutants. Different methods are used for stability determination with varying degrees of complexity. Most of these methods are based on the relative magnitude of convective and mechanical turbulence in atmospheric motions, such as Richardson number, Monin-Obukhov length, Pasquill-Gifford stability classification and Pasquill-Turner stability classification. The Pasquill-Turner Method (PTM), which is employed in this study used Observations of wind speed, solar altitude angle and the time of day to classify atmospheric stability with distinguishable indices. As a case study, meteorological data that gathered from European Centre For Medium-Range W

... Show More
View Publication Preview PDF
Publication Date
Mon May 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Foliar Applied Potassium and Cytokinin On Some Growth Parameters Of Lentil Plant (Lens culinaris Medic.).
...Show More Authors

The experiment was conducted in the glasshouse of Biology Dept. ,College of Education
Ibn- Al- Haitham ,University of Baghdad, during the growing season(2011), to study the
effect of sprying potassium sulphate at (0,200,400,600) ppm and cytokinin at (0,75,150)ppm
and their interactions on number of branches , protein percentage , carbohydrate percentage ,
absolute growth rate , biomass duration , relative efficiency of fertilizer and value of the
secondary productivity ,in Lentil plant cultivar(Baraka).
Results indicated that foliar sprying of potassium sulphate and cytokinin and their
interactions gave a significant effect on all vegetative growth parameters of lentil plant. the
concentration600 ppm of po

... Show More
View Publication Preview PDF
Publication Date
Tue Jun 30 2015
Journal Name
Al-khwarizmi Engineering Journal
The Influence of the Magnetic Abrasive Finishing System for Cylindrical Surfaces on the Surface Roughness and MRR
...Show More Authors

Abstract

Magnetic abrasive finishing (MAF) is one of the advanced finishing processes, which produces a high level of surface quality and is primarily controlled by a magnetic field. This paper study the effect of the magnetic abrasive finishing system on the material removal rate (MRR) and surface roughness (Ra) in terms of magnetic abrasive finishing system for eight of input parameters, and three levels according to Taguchi array (L27) and using the regression model to analysis the output (results). These parameters are the (Poles geometry angle, Gap between the two magnetic poles, Grain size powder, Doze of the ferromagnetic abrasive powder, DC current, Workpiece velocity, Magnetic poles velocity, and Finishi

... Show More
View Publication Preview PDF
Publication Date
Sat Jun 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Elements of the economic intelligence of the organization and its role in achieving economic growth: Applied research
...Show More Authors

   The aim of the research is to demonstrate of the relation and the influence of the components of economic intelligence (strategic alertness, information security policy, impact policy) in achieving of economic growth (creativity, competitiveness, quality improvement). The questionnaire was used as a main tool for selected sample. Answers analyzed by using the statistical program (SPSS)  to calculate the arithmetic mean, standard deviation, weight percentage, correlation, F test, and Squared factor (R2).

 The research derived its importance from the distinguished role of information systems in the work of industrial companies, and its impact toward achieving economic growth rates in its various activities. T

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Dec 08 2023
Journal Name
Iraqi Journal Of Science
Effect of Toxoplasmosis Infection on Liver and Kidney Functions among Pregnant Women in Abo-Gharib District- Iraq
...Show More Authors

The effect of toxoplasmosis infection on liver and kidney functions among pregnant women in Abo-Gharib District- Iraq was studied. Forty women that had positive test for toxoplasmosis by ELISA test were participated in this study. Also control group of apparently healthy women was selected (ten total women). This group had negative test for toxoplasmosis (ELISA test). The venous blood was collected from each patient and control individual to obtain serum. Liver function was evaluated by the estimation of serum aspartate aminotransferase (AST/GOT), serum alanine aminotransferase (ALT/ GPT) and serum alkaline Phosphatase (ALP) activities. Kidney function was evaluated by the estimation of serum creatinine and urea concentrations by the enz

... Show More
View Publication Preview PDF
Publication Date
Fri Jan 01 2021
Journal Name
Journal Of Economics And Administrative Sciences
Evaluation suppliers according to the integration of the Quality Function Deployment and the Fuzzy Analytic Hierarchy Process
...Show More Authors

The process of evaluating business processes, complex, repetition of procurement processes, need for raw materials and frequency of demand, which makes dealing with suppliers in the evaluation process, making the need for a process intervention in the process. Lighter on the other hand.

Many Iraqi companies suffer from problems related to suppliers, and cases of administrative and financial corruption are often raised regarding this type of contract and from this reality the necessity of researching this problem and trying to develop some solutions to reduce its impact on the companies' work, by using a method that works according to the standards adopted in Evaluation and selection of the supplier in the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Dec 26 2018
Journal Name
Iraqi Journal Of Science
Use Isotopes to Identity the Origin of Surface Water and Groundwater in ameriyat AL-Fallujah, Center Iraq
...Show More Authors

     Isotope tracer methods were used to determine flow paths, recharge areas, and relative age for groundwater in the Ameriyat Al- Falluja Al-Anbar governorate. The isotope of surface water and groundwater in the Ameriyat Al- Falluja area was assessed using a stable isotope technique. Data stable isotope parameters (2H and 18O) for three surface water and five groundwater samples were detected. The comparison of hydrogen and oxygen isotope compositions between groundwater and Euphrates River water demonstrated that the composition of the hydrogen and oxygen isotopes from Euphrates River matched that of the local meteoric water. This indicated that rainfall is the primary source of the river wate

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
The Decent Work Impact in Enhancing Job Immersion/ An Applied Research in Labour and Vocational Training Directorate
...Show More Authors

The research aims to identify decent work and its impact in enhancing job immersion. The questionnaire was adopted as a tool to analyze the sample responses of (81) workers to represent an estimated response rate of (88 per cent) out of the total population of (92) individuals. The research adopted descriptive-analytical approach, and reliability calculation, arithmetic means standard deviations, relative importance, and regression analysis adopted on SPSS v.25. The conclusion shows that there is a medium correlation between decent work and job immersion, and there is a low impact of decent work with its dimensions in job immersion; extract the most important acceptable components for job from the sample point of view about the o

... Show More
View Publication Preview PDF
Crossref (1)
Crossref