Based on Lyapunov exponent criterion, the aircraft lateral-directional stability during critical flight cases is presented. A periodic motion or limit cycle oscillation isdisplayed. A candidate mechanism for the wing rock limit cycle is the inertia coupling between an unstable lateral-directional (Dutch roll) mode with stable longitudinal (short period) mode. The coupling mechanism is provided by the nonlinear interaction of motion related terms in the complete set equations of motion. To analyze the state variables of the system, the complete set of nonlinear equations of motion at different high angles of attack are solved. A novel analysis including the variation of roll angle as a function of angle of attack is proposed. Furthermore the variation of Lyapunov exponent parameter as function of time is introduced. The numerical result indicated that the system became lightly damped at high angle of attack with increasing the amplitude of aircraft state variables limit cycle. A good agreement between the numerical result and published work is obtained for the onset of limit cycle oscillation, almost at .
In the present work, the behavior of thick-walled cylinder of elasto-plastic material (polymeric material) has been studied analytically. The study is based on modified Von-Mises yield criterion (for non metallic material). The equations of stress distribution are obtained for the cylinder under general cases of elastic expansion, plastic initiation and elastic-plastic expansion.
A computer program is developed for evaluating the stress distribution. The solution is carried out for worst boundary conditions when the cylinder is subjected to the combination of pressure load, inertia load, and temperature gradient.
The results are presente
... Show MoreIntelligence is the production of nervous system function and it's contents memory and creative thinking and understanding and other processes. It's a general cognitive ability and it's a concept. It's essential for good judgment and reasoning, there's an argument about definition of intelligence, is it one ability or multiple abilities. Multiple intelligences theory presented by (Gardner 1983) view intelligence as composing from six types of intelligences: (1) linguistic. (2) mathematical. (3) visual – spatial. (4) musical. (5) bodily – kinesthetic. (6) personal. Present research has reached to several conclusions. Most important one is that multiple intelligences theory is based on the conception of distinct varieties of intelligen
... Show MoreBackground: Despite the recently improved neonatal intensive management, gastrointestinal perforation during the neonatal period is still a major challenge for pediatric surgeons.
Objective: To review the effects of different clinical and operative parameters on the mortality of neonatal intestinal perforations.
Patients and Methods: A retrospective study was done to 31 cases of neonatal intestinal perforation at the neonatal intensive care unit of Basrah children speciality hospital during the past four and half years (July 2011 to December 2015). Information regarding the age, sex, gestational age, birth weight, clinical examination, x-rays value in diagnosis, causes and sites of perforations, types of operative procedures, and t
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Regression testing is a crucial phase in the software development lifecycle that makes sure that new changes/updates in the software system don’t introduce defects or don’t affect adversely the existing functionalities. However, as the software systems grow in complexity, the number of test cases in regression suite can become large which results into more testing time and resource consumption. In addition, the presence of redundant and faulty test cases may affect the efficiency of the regression testing process. Therefore, this paper presents a new Hybrid Framework to Exclude Similar & Faulty Test Cases in Regression Testing (ETCPM) that utilizes automated code analysis techniques and historical test execution data to
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The diverse urban spaces of the streets is an important part of the city's physicist configuration and a link between architectural and civilizational communication through time starting from the historic towns down to the contemporary cities, within the proposals of the future cities. From general observations and literature review a research problem is crystallized as some directions not arbitrary rational when expansion and the growth of cities, and other measures wrong or the existence of some incorrect actions and processes related to the cities planning as a categorizing the goals and priorities in city plan.The streets were constitute a high proportion of the total area of cities, where up to over 30% in major cities. These
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Background: Concha bullosa is an anatomical variation which defined by pneumatizaton of middle turbinate that occurred with an incidence of (5 to 25%) in the normal population.It has the potential to cause crowding and obstruction of the middle meatus and nasal cavity. There are many surgical techniques which utilized for its management. Study goal: Is to compare the formation of adhesion between endoscopic partial lateral middle turbinectomy and middle turbinate trimming in cases of concha bullosa. Patients and methods: A prospectivecomparative clinical trial was performed in the ENT department at Al-Shahid Ghazi AL Hariri Hospital in Medical City over the period from September 2016 to August 2017. Fifty nine (59) patients {24 males
... Show MoreBackground:Breast carcinoma is the most common malignant tumor and the leading cause of carcinoma death in women, with more than 1,000,000 cases occurring worldwide annually.(1) as a matter of fact , the mortality rate for breast carcinoma changed very little from the 1930s to the early 1990s, because of the combined action of earlier diagnosis and improved therapy .<br />Materials and methods: The prospective study included 500 cases of breast carcinoma who went total mastectomy , between October 2006- April 2007, where taken from private pathology laboratory , sections(4microns) are taken and stained with H&E stain and over-reviewed.<br />Results: Clinicopathological analysis of the 500 cases of breast carcinoma, includ
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Seeing Allah Almighty
Detective according to incoming nodules
In the interpretation of Ibn Arabi Maliki
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In this paper, we build a fuzzy classification system for classifying the nutritional status of children under 5 years old in Iraq using the Mamdani method based on input variables such as weight and height to determine the nutritional status of the child. Also, Classifying the nutritional status faces a difficult challenge in the medical field due to uncertainty and ambiguity in the variables and attributes that determine the categories of nutritional status for children, which are relied upon in medical diagnosis to determine the types of malnutrition problems and identify the categories or groups suffering from malnutrition to determine the risks faced by each group or category of children. Malnutrition in children is one of the most
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The presented work shows a preliminary analytic method for estimation of load and pressure distributions on low speed wings with flow separation and wake rollup phenomena’s. A higher order vortex panel method is coupled with the numerical lifting line theory by means of iterative procedure including models of separation and wake rollup. The computer programs are written in FORTRAN which are stable and efficient.
The capability of the present method is investigated through a number of test cases with different types of wing sections (NACA 0012 and GA(W)-1) for different aspect ratios and angles of attack, the results include the lift and drag curves, lift and pressure distributions along the wing s
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