For many problems in Physics and Computational Fluid Dynamics (CFD), providing an accurate approximation of derivatives is a challenging task. This paper presents a class of high order numerical schemes for approximating the first derivative. These approximations are derived based on solving a special system of equations with some unknown coefficients. The construction method provides numerous types of schemes with different orders of accuracy. The accuracy of each scheme is analyzed by using Fourier analysis, which illustrates the dispersion and dissipation of the scheme. The polynomial technique is used to verify the order of accuracy of the proposed schemes by obtaining the error terms. Dispersion and dissipation errors are calculated and compared to show the features of high order schemes. Furthermore, there is a plan to study the stability and accuracy properties of the present schemes and apply them to standard systems of time dependent partial differential equations in CFD.
Abstract
This paper concerned with study the effect of a graphite micro powder mixed in the kerosene dielectric fluid during powder mixing electric discharge machining (PMEDM) of high carbon high chromium AISI D2 steel. The type of electrode (copper and graphite), the pulse current and the pulse-on time and mixing powder in kerosene dielectric fluid are taken as the process main input parameters. The material removal rate MRR, the tool wear ratio TWR and the work piece surface roughness (SR) are taken as output parameters to measure the process performance. The experiments are planned using response surface methodology (RSM) design procedure. Empirical models are developed for MRR, TWR and SR, using the analysis
... Show MoreEmployee Stealing or internal theft is considered from the passive practices that can’t be denied or be hidden, In spite of the hospital privacy as a serving organization that works 24\7 and deleing with human lives, they weren’t infallible from that kind of practice. To prevent or reduce this practice, it was important to search for the organizational and behavioral factors influencing internal thefts. The study problem briefly is to reach the most organizational and behavioral factors influencing internal theft, in governmental hospitals in Baghdad Rusafa Health district, this was done by analyzing (20) administrative cases of thefts occurred in the District, also a sample of (60) specialist Doctor’s opinion work, in (3) hospital
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The research seeks to identify the role of the International Assurance Standard (3402) in the auditor's procedures, as the importance of the research stems from providing assurance services for control tools through reports that are prepared according to this standard, which contribute to strengthening audit procedures through a proposed assurance program. Many conclusions were reached, the most important of which The assurance operations are considered among the operations with a special assignme
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Abstract
Due to the lack of previous statistical study of the behavior of payments, specifically health insurance, which represents the largest proportion of payments in the general insurance companies in Iraq, this study was selected and applied in the Iraqi insurance company.
In order to find the convenient model representing the health insurance payments, we initially detected two probability models by using (Easy Fit) software:
First, a single Lognormal for the whole sample and the other is a Compound Weibull for the two Sub samples (small payments and large payments), and we focused on the compoun
... Show MoreThe features of the actor's performance in the ritual theater are of great importance and chief in theatrical work since the first emergence of the theater, as the features of the performance were embodied in all Iraqi theatrical performances, but they took personal privacy in some ritual performances because of their differences and similarities between the ritual theatrical performance and the ritual show Al-Khalis, who wanted the researcher to know the similarities and differences in the features of the ritual performance and in the theatrical performance, despite the many transformations that occurred in the theater and affected the features of the performance, but it remained an important and attractive link between the recipient, t
... Show MoreThe political movements of Islam are among the most prominent phenomena of the popular uprisings witnessed by the Arab world. However, this rise and the rise of some movements led to many problems on the political theses of Islam, especially those associated with the ideas of Islamic ideologues and their slogan Legitimacy and the authorities as the origin of the divine, and said the application to achieve the Islamic solution, and then became the state in theses of some Islamists a tool to apply the law and then the preservation of religion.
The present study aims to identify the most and the least common teaching practices among faculty members in Northern Border University according to brain-based learning theory, as well as to identify the effect of sex, qualifications, faculty type, and years of experiences in teaching practices. The study sample consisted of (199) participants divided into 100 males and 99 females. The study results revealed that the most teaching practice among the study sample was ‘I am trying to create an Environment of encouragement and support within the classroom which found to be (4.4623). As for the least teaching practice was ‘I use a natural musical sounds to create student's mood to learn’ found to be (2.2965). The study results also in
... Show MoreNigella sativa seeds (NSS) are reputed traditionally and scientifically as a potent agent that promote milk secretion (galactagogue), but their mechanism of action is studied trivially. One suggestion was that these seeds are bio-transformed to sex hormones within the ovaries. Therefore, this investigation was designated to throw light on the action of these seeds in the absence of ovaries i.e. in male rats. Thirty Norway male albino rats were used in this investigation. They were divided into experimental (n=20,fed NSS 2g/ Kg body weight /day for 14 days) and control (n=10, fed placebo for 14 days). After sacrifice mammary gland and blood samples were obtained. Experimental rats revealed a significant increase (p (0.01>in
... Show MoreKlebsilla pneumoniae is one of must opportunistic pathogens that causes nosocomial infection, UTI, respiratory tract infections and blood infections. ZrO2 nanoparticles have antimicrobial activity against some pathogenic bacteria and fungi. Ceftazidime is one of third generation cephalosporins groups of antibiotecs, characterized by its broad spectrum on bacteria in general and particularly on Enterobacteriaceae family like Klebsiella spp. Method: Diverse clinical samples of Klebsilla pneumoniae were isolated from several hospitals in Baghdad – Iraq and ZrO2 nanoparticles was investigated against it. Ceftazidime was also investigated against K. pneumoniae. Both of ZrO2 nanoparticles and ceftazidime were mixed together and investigated aga
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