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Adaptive Coded Modulation for OFDM System
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This paper studies the adaptive coded modulation for coded OFDM system using punctured convolutional code, channel estimation, equalization and SNR estimation. The channel estimation based on block type pilot arrangement is performed by sending pilots at every sub carrier and using this estimation for a specific number of following symbols. Signal to noise ratio is estimated at receiver and then transmitted to the transmitter through feedback channel ,the transmitter according to the estimated SNR select appropriate modulation scheme and coding rate which maintain constant bit error rate
lower than the requested BER. Simulation results show that better performance is confirmed for target bit error rate (BER) of (10-3) as compared to conventional modulation schemes, the convolutional coded modulation offers a SNR gains of 5 dB compared to uncoded state at BER of 10-3. The proposed adaptive OFDM scheme maintains fixed BER under changing channel conditions.

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Publication Date
Wed Jun 29 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
A Comparison Study for The Performance of Polyethersulfone Ultrafiltration Mixed Matrix Membranes in The Removal of Heavy Metal Ions from Aqueous Solutions
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Polyethersulfone (PES) ultrafiltration membrane blending NaX zeolite crystals as a hydrophilic additive was examined for zinc (II) and lead ions Pb (II) removal from aqueous solutions. The effect of NaX zeolite content on the permeation flux and removal efficiency was studied. The results showed that adding zeolite to the polymer matrix enhanced the permeation flux. The permeation flux of all the zeolite/PES matrix membranes was higher than the pristine membrane. No significant improvement was observed in the removal of Zn (II) ions using all prepared membranes as the removal percentage did not raise above 29.2%. However, the removal percentage of Pb (II) ions was enhanced to 97% using a membrane containing 0.9%wt. zeolite. Also, it was

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Publication Date
Sat Jan 01 2022
Journal Name
Optik
Plasma parameters of Au nano-particles ablated on porous silicon produced via Nd-YAG laser at 355 nm for sensing NH3 gas
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a laser ablation Q-switched Nd: YAG laser with a wave-length of 355 nm at a variety of laser pulse energies (E) and deposited on porous silicon (PS). Optical emission spectrometer was used to diagnosed medium air to study gold plasma characteristics and prepared Au nanoparticles. The laser pulse energy influence has been studied on the plasma characteristics in air. The data showed the emergence of the ionic (Au II) spectral emission lines in the gold plasma emission spectrum. XRD has been utilized to examine structural characteristics. Moreover, AFM results 37.2 nm as the mean value of the diameter that is coordinated in a shape similar to the rod that appears for Au NPs, in addition to that, TEM has been an indication of the fact that syn

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Publication Date
Tue Oct 20 2026
Journal Name
Karbala Journal Of Physical Education Sciences
Training of different ranges using the (HC-SR04 ultrasonic sensor ) and its effect in developing some of special abilities for young boxers
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Publication Date
Tue Feb 26 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Role Lean Accounting in Support Corporate Governance to Achieve a Competitive Advantage: An Application Study in Diala State Company for Electrical industrial
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        The modern business environment has witnesses tremendous developments as a result of the globalization of markets and economic openness and technological as well as the acquisition of the issue of corporate governance of great importance regarding it as one of the global innovations trends of control provisions on the management of companies as result of these developments ,increasing on competition between economic unit ,thus a decrease in market share because they do not take into account the response to the requirements of customers ,which kept her to search a modern management accounting methods to help them keep up with the changes and the availability of information for the various adminis

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Adoption of multi – model Assignment Fuzzy to find Optimizing for the use of internet line in the Ministry of Science and Technlogy
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We have provided in this research model multi assignment  with  fuzzy function goal has been to build programming model is correct Integer Programming fogging  after removing the case from the objective function data and convert it to real data .Pascal triangular graded mean using Pascal way to the center of the triangular.

The data processing to get rid of the case fogging which is surrounded by using an Excel 2007 either model multi assignment  has been used program LNDO to reach the optimal solution, which represents less than what can be from time to accomplish a number of tasks by the number of employees on the specific amount of the Internet, also included a search on some of the

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Publication Date
Sat Jan 01 2022
Journal Name
Geotechnical Engineering And Sustainable Construction
Determine the Most Common Geotechnical Risks and Their Impacts on the Cost and Time Schedule for Implementing Water Treatment Plants in Iraq
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Publication Date
Thu Jun 30 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Determination of the Optimum Conditions for the Production of Gamma Alumina (ɤ-Al2O3) By the Precipitation Method of the Sodium Aluminate Solution
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Design of experiments (DOE) was made by Minitab software for the study of three factors used in the precipitation process of the Sodium Aluminate solution prepared from digestion of α-Al2O3  to determine the optimum conditions to a produce Boehmite which is used in production of ɤ-Al2O3 during drying and calcination processes, the factors are; the temperature of the sodium aluminate solution, concentration of HCl acid added for the precipitation and the pH of the solution at which the precipitation was ended. The design of the experiments leads to 18 experiments.

   The results show that the optimum conditions for the precipitation of the sodium aluminate solution which

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Publication Date
Tue Feb 14 2023
Journal Name
Journal Of Educational And Psychological Researches
The Effectiveness of Teaching Practices of Science and Mathematics Teachers Based on the National Framework for Future Skills in the Omani School
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Abstract

The research aims to identify the level of effectiveness of the teaching practices of science and mathematics teachers in light of the national framework for future skills in Omani schools. To achieve the objectives of the study, the researchers used the descriptive approach, as he designed a note card consisting of (30) phrases distributed on three axes: basic skills, practical skills, and technical skills. After verifying the validity and reliability of the tools, they were applied to a sample of (116) teachers. The results of the research revealed that the level of effectiveness of the teaching practices of mathematics teachers has recorded a medium degree with a mean (3.05). The results a

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Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Al-nahrain University-science
Synthesis of Polyacrylamides from Derivatives 2-Aminobenzothiazole and also Preparation of Dibutylphthalate as a Plasticizer to Estimate Plasticization Behaviour for Prepared Polymers
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Publication Date
Thu Aug 31 2017
Journal Name
Journal Of Engineering
The Effect of Cyclic Bending Loads on Crack Growth in Pipes for Inclined and Transverse Cracks with or Without Internal Pulsing Pressure
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In the present research a new test rig has been proposed to be suitable for different cyclic loads such as cyclic bending, cyclic torsion, proportional and non proportional loads. In this work the efforts were concentrated on the cyclic bending loads concerning cracked pipes with or without internal pulsing pressure to study crack propagation in small bore pipes (up to 1'') for transverse or inclined cracks. The rig simulates the real service conditions under different stresses by means the least dangerous case will be suggested, so the experiments were considered for copper pipe, and the results have been tabulated and drawn to demonstrate the crack growth behavior as well as to justify the outcomes practically, consequently the durabil

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