Preferred Language
Articles
/
joe-2256
Effect of Design Parameters and Support Conditions on Natural Frequency of Pipe Excited by a Turbulent Internal Flow
...Show More Authors

In this study, the effect of design parameters such as pipe diameter, pipe wall thickness, pipe material and the effect of fluid velocity on the natural frequency of fluid-structure interaction in straight pipe conveying fully developed turbulent flow were investigate numerically,analytically and experimentally. Also the effect of support conditions, simply-simply and clamped-clamped was investigated. Experimentally, pipe vibrations were characterized by accelerometer mounted on the pipe wall. The natural frequencies of vibration were analyzed by using Fast Fourier Transformer (FFT). Five test sections of two different pipe diameters of 76.2
mm and 50.8 mm with two pipe thicknesses of 3.7 mm and 2.4 mm and two pipe materials,stainless steel and polyvinyl chloride PVC in the range of Reynolds numbers from 4*104 to 5*105 were studied. Mathematically, the governing continuity and momentum equations were solved numerically by using the finite volume method to compute the characteristics of two dimensional turbulent flow. The dynamics of a pipe conveying fluid was described by the Transfer Matrix Method (TMM) which is provides a numerical technique for solving the equations of pipe vibrations for simply-simply and clamped supports. The results showed that,the natural frequencies increase with pipe diameter increase and the natural frequencies slightly increases with pipe wall thickness increase. Also, the natural frequencies in clamped-clamped supported pipe are higher than those in simply-simply supported pipe.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Dec 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Genetic Algorithm Based PID Controller Design for a Precise Tracking of Two-Axis Piezoelectric Micropositioning Stage
...Show More Authors

 In this paper, an intelligent tracking control system of both single- and double-axis Piezoelectric Micropositioner stage is designed using Genetic Algorithms (GAs) method for the optimal Proportional-Integral-Derivative (PID) controller tuning parameters. The (GA)-based PID control design approach is a methodology to tune a (PID) controller in an optimal control sense with respect to specified objective function. By using the (GA)-based PID control approach, the high-performance trajectory tracking responses of the Piezoelectric Micropositioner stage can be obtained. The (GA) code was built and the simulation results were obtained using MATLAB environment. The Piezoelectric Micropositioner simulation model with th

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Accounting measurement of strategic storage in light of government support and its implications for presentation and disclosure / proposed model: an analytical study at the General Company for Grain Trade
...Show More Authors

يؤدي عرض معلومات مضللة او محرفة ضمن القوائم المالية والتي تعد أهم مصادر المعلومات الموثوقة التي يُعول عليها لاتخاذ القرارات السليمة الى عدم قدرتها على عكس نتيجة النشاط والمركز المالي لها او اعمال الوحدة الاقتصادية لتلك الفترات الزمنية بصورة صادقة وعادلة نتيجة لنوعية المعلومات المفصح عنها في القوائم المالية لذلك زاد الاهتمام بتطوير الممارسات المحاسبية لتتضمن افصاحات كافية بغرض اعطائهم صورة صادقة وعادلة

... Show More
View Publication Preview PDF
Publication Date
Fri Dec 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
Effect of Addition Different Levels of Kojic Acid and Sodium Alginate as a substitutes of conventional Antibiotic on the Characteristics of Cryopreserved Semen of Buffalo Bulls
...Show More Authors
Abstract<p>This experiment examined the effects of adding sodium alginate and KOJIC acid as substitutes of Conventional antibiotics to soybean lecithin extender on the characteristics of cryopreserved and frozen buffalo bull semen, as well as evaluation of their additions as antibiotics that to help lowering the microbial load. Following the collection and dilution of in the soybean lecithin extender, the experimental treatments were separated into five groups, as follows: T1: (control-) without adding any antibiotics; T2: (control+) adding the conventional antibiotics Gentamicin 0.4 IU and Tylosin 0.08 IU per 100 ml; T3: adding Kojic acid at (0.06 g/L) T4: adding sodium alginate at (0.6 mg/mL)T</p> ... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Sat Oct 20 2018
Journal Name
Journal Of Economics And Administrative Sciences
Fluctuations of global crude oil prices and their effect on inflation and economic growth in Iraq " A standard study for the period 1988– 2015
...Show More Authors

Abstract

That Iraq's dependence on the revenues of the oil product in financing its development programs and growth rates , Making the economy affected by external forces represented by fluctuations in crude oil prices in the global market, Which is directly reflected on the performance and efficiency of the Iraqi economy.

The study adopted its objectives to analyze the time series for the period (1988 - 2015) through the use of standard and statistical methods, Four standard models were estimated to reach those targets, Where the results of the stability test showed instability of most variables at their original level, But to achieve stability when taking the first differences, While the result

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat Apr 01 2023
Journal Name
Journal Of Engineering
Minimum Instream Environmental Flow in Shatt Al-Hillah River
...Show More Authors

To maintain river flows necessary to meet social and ecological objectives, instream environmental flows are frequently used as a strategy. The capability of three alternative historical flow approaches to protect against low flows is shown in this study using gage stations in the Shatt Al-Hillah River in Iraq. The extension of the Shatt al-Hillah River is the focus of this research discussion on environmental flow assessment. The available data on discharge in this research were adopted for ten years from 2012-2021. Different flow methods were adopted to establish a minimum environmental flow in the Shatt Al-Hillah River. Three hydrological-based approaches: Tennant, modified Tennant, and low-flow metrics like 7Q10, wer

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Physics: Conference Series
Gamma Irradiation Effects on Energy Transfer Parameters for Acrvlaven – Rhodamine19 Binary Laser Dye Mixtures
...Show More Authors

View Publication
Scopus Clarivate Crossref
Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Physics: Conference Series
Gamma Irradiation Effects on Energy Transfer Parameters for Acrvlaven – Rhodamine19 Binary Laser Dye Mixtures
...Show More Authors

View Publication
Scopus Clarivate Crossref
Publication Date
Tue Jun 25 2024
Journal Name
African Journal Of Biological Sciences
Toxic effect of Thiamethoxam and Lambda cyhalothrin on Nephrotoxicity and Hematological in rats
...Show More Authors

Thiamethoxam is a synthetic organic insecticide belong to The most significant new class of pesticides created in the last thirty years is neonicotinoids. This study's objective was to determine the effect of thiamethoxam, lambda cyhalothrin and their combination on biochemical parameters, the levels of free radicals and enzymes activities liver of male.Forty Rats ( 150-170 g ) were used. animals Were separated into four groups, each with ten rats.The Gp1 was used as control, the Gp2 was used to study the effect of thiamethoxam for 3weeks, the Gp3 was employed to examine the impact of lambda cyhalothrin for 3 weeks and the Gp4 was used to research the impact of thiamethoxam and lambda cyhalothrin for 3 weeks. thiamethoxam and/or lambda cyha

... Show More
View Publication Preview PDF
Publication Date
Tue Jan 01 2019
Journal Name
Indian Journal Of Public Health Research &amp; Development
Effect of Gold Nanoparticles and Laser on Platelet, Lymphocytes, and White Blood Cells
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Fri Jun 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The tax planning and its effect on the investment: On sample of Iraqi Contribution Company
...Show More Authors

The importance of the current study  lies in the  importance of the  Tax policy that  being considered one of the most important tools working on fulfilling  the  social,  financial  and economic  goals  and improving  the investment environment  in the country  to become  having the ability to  activate the  national economy. The current study  has  referred  that  (  Has  the  tax planning  practiced by  the Iraqi  contribution  companies  led to increase  the  far-term tax  outcome through  getting  benefit of   the monetary  funds  and expansion in&nbs

... Show More
View Publication Preview PDF
Crossref