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Power Efficiency Maximization in Cognitive Radio Networks
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Cognitive radio technology is used to improve spectrum efficiency by having the cognitive radios act as secondary users to access primary frequency bands when they are not currently being used. In general conditions, cognitive secondary users are mobile nodes powered by battery and consuming power is one of the most important problem that facing cognitive networks; therefore, the power consumption is considered as a main constraint. In this paper, we study the performance of cognitive radio networks considering the sensing parameters as well as power constraint. The power constraint is integrated into the objective function named power efficiency which is a combination of the main system parameters of the cognitive network. We prove the existence of optimal combination of parameters such that the power efficiency is maximized. Then we reformulate the objective function to incorporate the throughput. According to different constraints or degree of significance, we may put proper weight to each term so that we could obtain more preferable combination of parameters. Computer simulations have given the optimal solution curve for different weights. We can draw the conclusion that if we put more emphasis on power efficiency, the transmit power is a more critical parameter, however if throughput is more important, the effect of sensing time is significant.

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Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
Surface Modification of the Improved Stainless Steel Alloy AISI-304 and the Use of Diffusion Coating and a Study of Its Efficiency in Resistivity Hot Corrosion in an Atmosphere of Sodium Chloride Vapor NaCL and Sodium SulfateNa_2 SO_4
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       This research aims to modify the components of stainless steel alloy by the method of surface engineering through the single diffusion coating technique in order to obtain new alloys with high efficiency in resisting harsh environmental conditions. Steam a mixture of sodium chloride ( ) and sodium sulfate ( ) at a temperature of 900 and then compare it with the base alloy. The results showed that the alloys produced in this way are very efficient. The results showed that the aluminum coating showed high efficiency in resisting oxidation and provided better protection for a longer time compared to the uncoated alloy due to the  oxide crust layer formed with high adhesion as well as the aluminum-rich phases, whether the phase

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Publication Date
Mon Jun 04 2018
Journal Name
Baghdad Science Journal
Effect the Thickness on the Electrical Properties and (I-V) Character of the (CdTe) Thin Films and Find the Efficiency of Solar Cell CdTe/CdS
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Thin films of CdTe were prepared with thickness (500, 1000) nm on the glass substrate by vacuum evaporation technique at room temperature then treated different annealing temperatures (373,473,and 573)K for one hour. Results of the Hall Effect and the electrical conductivity of (I-V) characteristics were measured in darkness and light.at different annealing temperature results show that the thin films have ability to manufacture solar cells, and found that the efficient equal to (2.18%) for structure solar cell (Algrid / CdS / CdTe /glass/ Al) and the efficient equal to (1.12%) for structure solar cell (Algrid / CdS / CdTe /Si/ Al) with thick ness of (1000) nm with CdTe thin films at RT.

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Publication Date
Sun Jun 11 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Characterization of New Chelating Terpolymer Resin Derived from p-Amino Benzoic Acid, Biuret and Formaldehyde and Study Efficiency Extractive from Some Metal Ion
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  In this study terpolymer resin  ) p-ABBF) was prepared by condensation of (p-amino benzoic acid) and (Biuret) with formaldehyde in (1:1:3) mol ratio using hydrolic acid as a reaction medium at 130±2 ℃ .The synthesized terpolymer resin was characterized by elemental analysis , FT-IR and (1H-NMR) spectroscopy. The intrinsic viscosity was determined. The thermal stability of the terpolymer was analyzed by (TGA and DSC).The morphological feature of the (p-ABBF) terpolymer resin was studied by scanning electron microscopy (SEM).Bach equilibrium method was employed to study analytical efficiency of the terpolymer resin towards certain trivalent and divalent metal ions such as (Cu+2,Ni+2, Co+2,Zn+2,Cd+2 and Cr+3( where thes

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Publication Date
Tue Nov 09 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The role of the use of automated accounting systems technology in enhancing the efficiency and effectiveness of the internal control system.: دراسة تحليلية لعينة من الموظفين العاملين في اقسام المحاسبة والتدقيق في الجامعات البحرينية
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The research aims to show the relationship between the use of automated accounting systems technology and its impact on enhancing the efficiency and effectiveness of the internal control system in a sample of Bahraini universities in light of the rapid changes in the                                       electronic business environment. Automated accounting and its impact on enhancing the efficiency and effectiveness of the internal control system, and it is concluded through the analytical study of the research sample that there is a percenta

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Publication Date
Sat Jun 21 2025
Journal Name
Al-fatih Journal
Development of explosive power training with weights in a way the ups and downs and its impact on the improvement of some variables Albyukinmetekih and technical performance of the skill of a leap forward on your hands vaulting modern
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Publication Date
Fri Jan 01 2021
Journal Name
Review Of International Geographical Education Online
Measuring The Efficiency of The Departments of The College of Administration and Economics / University of Baghdad Using the Method of Data Envelopment Analysis (DEA), A Comparative Study
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The research aims at the possibility of measuring the technical and scale efficiency (SE) of the departments of the College of Administration and Economics at the University of Baghdad for a period lasting 8 years, from the academic year 2013-2014 to 2018-2019 using the method of Applied Data Analysis with an input and output orientation to maintain the distinguished competitive position and try to identify weaknesses in performance and address them. Nevertheless, the research problem lies in diagnosing the most acceptable specializations in the labor market and determining the reasons for students’ reluctance to enter some departments. Furthermore, the (Win4DEAp) program was used to measure technical and scale efficiency (SE) and rely on

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Scopus
Publication Date
Wed Jun 29 2022
Journal Name
Iraqi Journal Of Agricultural Sciences
EFFECT OF OZONE ENRICHMENT AND SPRAYING WITH ORGANIC NUTRIENT ON NUTRIENT AND WATER USE EFFICIENCY AND FERTILIZER PRODUCTIVITY OF BROCCOLI PLANT CULTIVATED HYDROPONICALLY WITH MODIFIED NFT TECHNOLOGY.
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This study was carried out at University of Baghdad - College of Agricultural Engineering Sciences - research station B during the fall season of 2019-2020, in order to evaluate the effect of Ozone enrichment and the foliar application of organic nutrient  on nutrient and water use efficiency and fertilizer productivity of broccoli plant using the modified NFT film technology. A factorial experiment (2*5) was carried out within Nested Design with three replicates. The ozone treatment was distributed into the main plots which consisted of oxygen (O2) and ozone (O3). The foliar application of organic nutrients were distributed randomly within each replicate including five treatments, which were the control treatment (T0), Coconut wat

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Publication Date
Fri Nov 05 2021
Journal Name
Review Of International Geographical Education Online
Measuring The Efficiency of The Departments of The College of Administration and Economics / University of Baghdad Using the Method of Data Envelopment Analysis (DEA), A Comparative Study
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Publication Date
Thu Apr 30 2020
Journal Name
International Journal Of Psychosocial Rehabilitation
The use of physical exercises specialized for with aids of developing explosive power for arms and legs and their effect on free throw and jump shooting skills for advanced basketball players
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The research aims to develop physical exercises with auxiliary training tools that work to develop the explosive power of the arms and legs, and then find out their effect on the accuracy of shooting from free throw and correction from jumping of advanced basketball players, as the researchers found a problem that these players have weakness in the skill of throwing Free throwing and shooting by jumping calculated with two points as a result of adopting unhealthy physical and technical positions, which led to a lack of focus and accuracy, and thus negatively affected the performance technique of free throw and jump shot, as most teams use traditional exercises without the use of auxiliary training tools, and this topic gave researchers the

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Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Efficiency of Human Resources Information System and Its Impact on The Level Effectiveness of Employees Performance Appraisal System / Practical Research on Ministry of Higher Education and Scientific Research
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Abstract

The research aims to determine the role of the efficiency of Human Resources Information System in the effectiveness of Employees Performance Appraisal System in the Ministry of Higher Education and Scientific Research / Center for the ministry, it was touching the researchers need the ministry to devise methods that employ outputs Human Resources Information System in the organization surveyed for the development of methods and levels of process evaluate the performance of its employees, in order to identify the extent of the role played by human resources information system in the process of assessing the performance of employees, we raised the question of the President as follows:

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