A two-dimensional computational study had been performed regarding aerodynamic forces and pressures affecting a cambered inverted airfoil, CLARK-Y smoothed with ground effects by solving the Reynolds-averaged Navier-Stokes equations, using the commercial software COMSOL Multiphysics 5.0 solver. Turbulence effects are modeled using the Menter shear-stress transport (SST) two-equation model. The negative lift (down-force), drag forces and pressures surface were predicted through the simulation of wings over inverted wings in different parameters namely; varying incidences i.e. angles of attack of the airfoils, varying the ride hide from the ground covering various force regions, two-dimensional cross-section of the inverted front wings to be fixed on nose of a race car- and varying speeds of initial airflow (Reynolds number). The results show that the down-force increases as the angle of attack increases; however, if an inverted wing is fixed on a car at high angles of attack the wing starts to stall which is not a desired condition that affects the vehicle stability and performance. As the ride height was reduced, the down-force was increased; at clearances between the suction surface and the ground of less than 0.2 of the chord length c, the down-force is significantly higher. Very close to the ground, at a ride height of less than 0.1c, down-force decreases as the wing stalls. Also, down-force increases as the free-stream velocity (Reynolds number) increases. The pressures for lower and upper surface of the wing increased with increasing both of angle of attack and ride height, but remains relatively ineffective with varying the speeds.
This paper aims to find new analytical closed-forms to the solutions of the nonhomogeneous functional differential equations of the nth order with finite and constants delays and various initial delay conditions in terms of elementary functions using Laplace transform method. As well as, the definition of dynamical systems for ordinary differential equations is used to introduce the definition of dynamical systems for delay differential equations which contain multiple delays with a discussion of their dynamical properties: The exponential stability and strong stability
This research is an attempt to study aspects of syntactic deviation in AbdulWahhab Al-Bayyati with reference to English. It reviews this phenomenon from an extra-linguistic viewpoint. It adopts a functional approach depending on the stipulates of systemic Functional Grammar as developed by M.A.K. Halliday and others adopting this approach. Within related perspective, fairly’s taxonomy (1975) has been chosen to analyze the types of syntactic deviation because it has been found suitable and relevant to describe this phenomenon. The research hypothesizes that syntactic deviation is pervasive in Arabic poetry, in general and in Abdul-Wahhab Al-Bayyati Poetry in specific, and can be analyzed in the light of systemic Functional Grammar
... Show MoreSalivary peroxidases have biological functions of particular importance to oral health. The aim of this paper is to shed the light on saliva and serum total peroxidases activity as well as the activity of each of salivary peroxidase (SPO) and myeloperoxidase (MPO) in patients with oral tumors. The studied participants were divided into two groups: the first group included 18 oral squamous cell carcinoma patients and 20 age and gender-matched healthy controls while the second group consisted of 20 oral ossifying fibroma patients and 23 age and gender-matched healthy controls. Total peroxidases activity was determined, and its specific activity was calculated in serum and whole mixed saliva as well as in the supernatant and pellet fractions
... Show MoreBackground: The present study aimed to assess the distribution, prevalence, severity of malocclusion in Baghdad governorate in relation to gender and residency Materials and Methods: A multi-stage stratified sampling technique was used in this investigation to make the sample a representative of target population. The sample consisted of 2700 (1349 males and 1351 females) intermediate school students aged 13 years representing 3% of the total target population. A questionnaire was used to determine the perception of occlusion and orthodontic treatment demand of the students and the assessment procedures for occlusal features by direct intraoral measurement using veriner and an instrument to measure the rotated and displaced teeth. Results a
... Show MoreIntroduction: Cutaneous leishmaniasis (CL) is a common protozoan disease in Iraq characterized by localized ulcers, primarily on exposed skin. This study aimed to investigate the hematological parameters of infected patients using a complete blood count (CBC) in the endemic area of Diyala Governorate, northeast of Baghdad. This has been studied in newly diagnosed, untreated individuals and patients receiving sodium antimony gluconate. Methodology: Hematological screening was performed on blood samples from 161 patients with microscopically diagnosed cutaneous leishmaniasis before and after treatment. Anti-Leishmania IgG was also assessed by ELISA in seropositive and seronegative subjects. Results: The newly diagnosed, untreated pati
... Show MoreMultiple linear regressions are concerned with studying and analyzing the relationship between the dependent variable and a set of explanatory variables. From this relationship the values of variables are predicted. In this paper the multiple linear regression model and three covariates were studied in the presence of the problem of auto-correlation of errors when the random error distributed the distribution of exponential. Three methods were compared (general least squares, M robust, and Laplace robust method). We have employed the simulation studies and calculated the statistical standard mean squares error with sample sizes (15, 30, 60, 100). Further we applied the best method on the real experiment data representing the varieties of
... Show MoreMy research to study the processes of the creation of shapes and encrypt any encryption in design forms and contents of computer technology as the creative property of definable and renewal, change and transformation process of transformative theme of shape, form and content encryption process in textile designs lets us know the meaning or substance which may be invisible to the encryption in the digital design of fabrics is a recruitment ideas modern and refined through a technique to accomplish the work of a beautiful audiences with novelty and innovation. The search includes four chapters:1Chapter I deal with the problem of research and its current research (form and content encryption with digital designs in women's contemporary fabr
... Show MoreAbstract Background: The hip joint and lumbar spine are both anatomically and functionally closely related as had shown by many authors. So the abnormality in one area can affect the other e.g. hip joint osteoarthritis can cause lumbar sagittal malalignment and backache. Objectives: is to see if there is significant improvement in backache after total hip replacement? And which degree of backache improvement is associated with significant changes in lumbar lordosis? Methods and patients: a prospective open trial study was performed on 30 patients who had severe hip osteoarthritis and chronic low back pain. Total hip replacement was performed to all patients. Backache and lumbar lordosis were measured by visual analogue scale and Cobb’s a
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