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Enhancing the Performance of Piezoelectric Energy Harvesters Using Permanent Magnets
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A cantilevered piezoelectric beam with a tip mass at its free end is a common energy harvester configuration. This paper introduces a new principle of designing such a harvester which increases the generated voltage without changing the natural frequency of the harvester: The attraction force between two permanent magnets is used to add stiffness to the system. This magnetic stiffening counters the effect of the tip mass on the natural frequency. Three setups incorporating piezoelectric bimorph cantilevers of the same type in different mechanical configurations are compared theoretically and experimentally to investigate the feasibility of this principle. Theoretical and experimental results show that magnetically stiffened harvesters have important advantages over conventional setups. They generate more voltage and they can be tuned across a wide range of excitation frequencies.

 

 

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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Additives on The Performance of Hydrostatic Thrust Bearings
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The paper is concerned with, the behavior of the hydrostatic thrust bearings lubricated with liquid-solid lubricants using Einstein viscosity formula, and taking into account the centrifugal force resulting from high speed.  Also studied is the effect of the bearing dimensions on the pressure, flow rate, load capacity, shear stress, power consumption and stiffness.

The theoretical results show an increase in load capacity by (8.3%) in the presence of solid graphite particles with concentration of (16%) by weight as compared with pure oil, with increasing shear stress.  .

In general the performance of hydrostatic thrust bearings improve for load carrying capacity, volume flow rate,

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Publication Date
Fri Dec 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Transparency of government performance to the state of iraq
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The most important recommendations of this research are:-

1.The benefit of the other countries experiences about the transparency of the government performance, without depending on the transparency that imitating the other experiences; that may not fit with the Iraqi government units.

2.The Ministry of Finance has to prepare the citizen guidebook about the government performance which is considered an essential document, it should be simple and available for all the parties of relation; and for not specialized citizen for the purpose of simplifying the understanding of government performance details.

3.The benefit of the government units websites of inte

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Publication Date
Tue Dec 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Study of the Performance of Batch Reactive Distillation Column
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Batch reactive distillation was studied in packed bed column. Esterification of methanol with acetic acid to produce methyl acetate and water with homogenous sulfuric acid as a catalyst was considered. This system was chosen because the reaction is reversible and the boiling point of reactant and products are different.
The reaction was carried out with and without distillation column and shows that the reactive distillation is more efficient from the conventional process (reactor and then separation). The conversion of acetic acid and concentration of methyl acetate increase by (30.43% and 75.14%) respectively at the best condition (reflux ratio 2, feed mole ratio 2 and batch time 90 minute).
The influence of various parameters, s

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Publication Date
Sun Jan 26 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Evaluation of Financial Performance of the Iraqi Insurance Company
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Insurance Companies perform a prominent role in providing services and bolstering national economy, and they contribute in achieving the aims of the economic development plans in addition to many other social and economic benefits. So it is necessary to evaluate the activity of these companies continuously to define performance level and its nature. Financial analysis is one of the important instruments that helps in analyzing and explanation of data in such a way that enable administration to define performance level and diagnosing strength and weakness points. This study tackles the state of affairs of the Iraqi Insurance Company which is considered as one of the active national institutions, due to its distinguished role in collecting

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Publication Date
Wed Sep 24 2025
Journal Name
Tropical Journal Of Pharmaceutical Research
Antibacterial-enhancing efficacy of aloe vera and honey in salicylic acid topical formulations against acne
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Purpose: To compare the antibacterial-enhancing efficacy of aloe vera and honey in salicylic acid topical formulations against acne. Method: Six formulations containing 5 % salicylic acid were developed as creams and gels as follows: Formulations S, V and H were creams containing salicylic acid alone (S), salicylic acid with 28 % aloe vera (V), and salicylic acid with 10 % honey (H). Formulations J, M, and B were gels containing salicylic acid alone (J), salicylic acid with aloe vera 20 % (M) and salicylic acid with 12 % honey (B). Each formula was evaluated for colour, odour, pH, viscosity, spreadability, and stability under different temperatures (25, 30, and 60oC) and times (1 hour, 1 day, and 1 week). Furthermore, antibacterial

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Publication Date
Sat Sep 01 2018
Journal Name
International Journal Of Heat And Mass Transfer
Accelerated melting of PCM in energy storage systems via novel configuration of fins in the triplex-tube heat exchanger
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Publication Date
Thu Jan 04 2024
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Marketing commission and its role in enhancing the competitive advantage of insurance companies : Applied research on a sample of Iraqi insurance companies
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Abstract:

                 The research aims to improve the insurance service through the marketing commission as a tool that enables the insurance companies to achieve a competitive advantage. The researcher, by observing the challenges faced by insurance companies, insurance agents and brokers, raised the main question of the research: Is there an effect of the marketing commission on the competitive advantage of insurance companies? The data was obtained through the financial statements and annual reports of the research sample companies (the National General Insurance Company, the Iraqi General Insurance Company, Al-Hamra Private

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Publication Date
Fri Dec 30 2011
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Energy Generation from Static Water Head Developed By Forward Osmosis
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In this work, the possibility of utilizing osmosis phenomenon to produce energy as a type of the renewable energy using Thin Film Composite Ultra Low Pressure membrane TFC-ULP was studied. Where by forward osmosis water passes through the membrane toward the concentrated brine solution, this will lead to raise the head of the high brine solution. This developed static head may be used to produce energy. The aim of the present work is to study the static head developed and the flux on the high brine water solution side when using forward and reverse osmosis membranes for an initial concentration range from 35-300 g/l for each type of membrane used at room temperature and pressure conditions, and finally calculating the maximum possible po

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Publication Date
Sat Dec 01 2018
Journal Name
2018 Third Scientific Conference Of Electrical Engineering (scee)
A UWB Monopole Antenna Design based RF Energy Harvesting Technology
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Recently, wireless charging based RF harvesting has interfered our lives [1] significantly through the different applications including biomedical, military, IoT, RF energy harvesting, IT-care, and RFID technologies. Wirelessly powered low energy devices become significantly essential for a wide spectrum of sensing applications [1]. Such devices require for low energy resources from sunlight, mechanical vibration, thermal gradients, convection flows or other forms of harvestable energy [2]. One of the emerging power extraction resources based on passive devices is harvesting radio frequency (RF) signals powers [3]–[5]. Such applications need devices that can be organized in very large numbers, so, making separate node battery impractical.

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Publication Date
Tue Jan 01 2019
Journal Name
Aip Conference Proceedings
Temperature dependence energy distribution function for proton-tritium fusion reaction
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The physical behavior for the energy distribution function (EDF) of the reactant particles depending upon the gases (fuel) temperature are completely described by a physical model covering the global formulas controlling the EDF profile. Results about the energy distribution for the reactant system indicate a standard EDF, in which it’s arrive a steady state form shape and intern lead to fix the optimum selected temperature.

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