Preferred Language
Articles
/
bsj-4024
Phase Fitted And Amplification Fitted Of Runge-Kutta-Fehlberg Method Of Order 4(5) For Solving Oscillatory Problems
...Show More Authors

In this paper, the proposed phase fitted and amplification fitted of the Runge-Kutta-Fehlberg method were derived on the basis of existing method of 4(5) order to solve ordinary differential equations with oscillatory solutions. The recent method has null phase-lag and zero dissipation properties. The phase-lag or dispersion error is the angle between the real solution and the approximate solution. While the dissipation is the distance of the numerical solution from the basic periodic solution. Many of problems are tested over a long interval, and the numerical results have shown that the present method is more precise than the 4(5) Runge-Kutta-Fehlberg method.

Scopus Clarivate Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Mar 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Comparison study of Information Criteria to determine the order of Autoregressive models
...Show More Authors

بهذا البحث نقارن معاييرالمعلومات التقليدية (AIC , SIC, HQ , FPE ) مع معيارمعلومات الانحراف المحور (MDIC) المستعملة لتحديد رتبة انموذج الانحدارالذاتي (AR) للعملية التي تولد البيانات,باستعمال المحاكاة وذلك بتوليد بيانات من عدة نماذج للأنحدارالذاتي,عندما خضوع حد الخطأ للتوزيع الطبيعي بقيم مختلفة لمعلماته

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Dec 01 2024
Journal Name
Materials Letters
Determination of third order susceptibility of carbon quantum dots at different concentrations
...Show More Authors

The nonlinear refractive (NLR) index and third order susceptibility (X3) of carbon quantum dots (CQDs) have been studied using two laser wavelengths (473 and 532 nm). The z-scan technique was used to examine the nonlinearity. Results showed that all concentrations have negative NLR indices in the order of 10−10 cm2/W at two laser wavelengths. Moreover, the nonlinearity of CQDs was improved by increasing the concentration of CQDs. The highest value of third order susceptibility was found to be 3.32*10−8 (esu) for CQDs with a concentration of 70 mA at 473 nm wavelength.

View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Sat Feb 02 2019
Journal Name
Journal Of The College Of Education For Women
The use of ionic pumping method for improving the performance of vacuum micro-electronic valves: The use of ionic pumping method for improving the performance of vacuum micro-electronic valves
...Show More Authors

Abstract
The use of electronic valves is commonly available. yet, the most
common is the techniques of communications as prod casting transmitter that
are used by these valves in addition to their use in communication tools as far
distance telephone, electronic measuring techniques , and others.
In this study, an attempt is endeavored for improving the efficiency of the
vacuum micro- valves(GI-19b) through activating their internal surfaces by the
use of ionic pumping which is used for treating valves which are out of order
(because of sedimentation some materials and oxide on its poles). The
existence of these materials and oxide increase the sum of current leakage
moving in between. The use of ionic pumpin

... Show More
View Publication Preview PDF
Publication Date
Fri Aug 07 2026
Journal Name
Iraqi Journal Of Science
UNSTEADY PRESSURE DROP AND HEAT TRANSFER OFMAGNETOHYDRODYNAMIC ANNULAR TWO-PHASE INRECTANGULAR CHANNEL
...Show More Authors

An annular two-phase, steady and unsteady, flow model in which a conductingfluid flow under the action of magnetic field is concavely. Two models arepresented, in the model one; the magnetic field is perpendicular to the long side ofthe channel, while in the model two is perpendicular to the short side. Also, westudy, to some extent the single-phase liquid flow.It is found that the motion and heat transfer equations are controlled by differentdimensionless parameters namely, Reynolds, Hartmann, Prandtl, and Poiseuilleparameters. The Laplace transform technique is used to solve each of the motion andheat transfer equations. The effects of each of dimensionless parameters upon thevelocity and heat transfer is analyzed.A comprehensive study fo

... Show More
View Publication Preview PDF
Publication Date
Thu Jul 18 2002
Journal Name
Phase Transitions
Designed new mesogens via Vilsmeier–Haack reagent: synthesis and phase transition study
...Show More Authors

A new four series of 2,2′-([1,1′- phenyl or biphenyl]-4,4′-diylbis(azanediyl)) bis(N′-((E)-1-(4-alkoxyphenyl) ethylidene) acetohydrazide) [V-XI]a,b and 1,1′-(2,2′-([1,1′- phenyl or biphenyl]-4,4′-diyl bis(azanediyl)) bis- (acetyl)) bis(3-(4-ethoxyphenyl)-1H-pyrazole-4-carbalde hyde) [XII-XVIII]a,b have been synthesized by varying terminal lateral alkoxy chain length (n = 1–3, 5–8), central linkage group (phenyl or biphenyl) and induced pyrazole heterocyclic ring in the main chain. The last two series were synthesized by the cyclization of substituted acetophenone hydrazones with Vilsmeier–Haack reagent (DMF/POCl3) to produce 4-formylpyrazole derivatives. The chemical structures of the synthesized compounds were examine

... Show More
Scopus (2)
Scopus
Publication Date
Fri Dec 15 2023
Journal Name
Al-academy
The extent of theatrical and musical arts contribute to the diagnosis And treatment of psychological problems Inmates of
...Show More Authors

 The research aims to identify the extent to which the theatrical and musical arts contribute to diagnosing and treating psychological problems among the residents of children’s villages in Jordan, and the methodologies adopted by the theatrical and musical arts to achieve this. It moves on to prove the theory that theatrical and musical arts have an impact on improving the psychology of the residents of children’s villages in Jordan by reviewing the theories and opinions that address the subject from a scientific point of view proven by experiences and expertise. The research took place in the period between (2019-2020), and the spatial limits came within the (SOS) children's villages in Jordan. The importance of the research is to

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Dec 01 2025
Journal Name
Journal Of University Of Anbar For Pure Science
Mobile ad hoc network wireless security: problems, solutions, and application: state-of-the-art
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Fri Mar 25 2016
Journal Name
Oriental Journal Of Chemistry
Synthesis and Antioxidant Ability of New 5-amino-1,2,4-Triazole Derivatives Containing 2,6-dimethoxyphenol
...Show More Authors

4-amino-3-(4-(((4-hydroxy-3,5dimethoxybenzyl)oxy)methyl)phenyl)-1,2,4-triazole-5-thione was synthesized by to method the first one from melt reaction of 4-(((4-hydroxy-3,5-dimethoxybenzyl)oxy)methyl)benzoic acid with Thiocarbonyldihydrazide, the second method from convert the corresponded acid hydrazide to potassium 2-(4-(((4-hydroxy-3,5-dimethoxybenzyl)oxy)methyl)benzoyl)hydrazinecarbodithioate salt then react with hydrazine hydrate. Newly Schiff base (7a-7f) were synthesized from reaction the 4-amino-1,2,4-triazol with substituted hydroxybenzaldehyde. The resulting compounds were characterized by IR, 1H-NMR, 13C-NMR, and HRMS data. 2,2-Diphenyl-1-picrylhydrazide (DPPH) and ferric reducing antioxidant power (FRAP) assays were used to scree

... Show More
Scopus (7)
Crossref (3)
Scopus Crossref
Publication Date
Thu Jul 07 2022
Journal Name
Public Works Management & Policy
Impact of Pandemic SARS COVID-19 on Different Construction Project Management: Problems and Solutions
...Show More Authors

This study discusses risk management strategies caused by pandemic-related (Covid-19) suspensions in thirty-six engineering projects of different types and sizes selected from countries in the middle east and especially Iraq. The primary data collection method was a survey and questionnaire completed by selected project crew and laborers. Data were processed using Microsoft Excel to construct models to help decision-makers find solutions to the scheduling problems that may be expected to occur during a pandemic. A theoretical and practical concept for project risk management that addresses a range of global and local issues that affect schedule and cost is presented and results indicate that the most significant delays are due to a

... Show More
Scopus (8)
Crossref (10)
Scopus Clarivate Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Indian Journal Of Ecology
Study on major constraints and problems in transfer of technology by agricultural extension organization
...Show More Authors

Scopus (6)
Scopus