A winglet is devices attached at the wing tips, used to improve aircraft wing efficiency by reduction influence wing tips vortices and induct drag, increasing lift force at the wing tips and effective aspect ratio without adding greatly to the structural stress and weight in the wing structure. This paper is presented three-dimensional numerical analysis to proposed modification swept back wing by adding Raked winglets devices at the main wing tips belong the two seat trainer aircraft type Aermacchi Siai S211 by using Fluent ANSYS 13 software. CFD numerical analysis process was performed at the same flight boundary conditions indifferent wing angle of attacks with constant air flow velocity V∞ =50 (m/sec), ambient pressure Po=101325 (Pa), ambient temperature To=288.14 (K), and at air density ρo=1.225 (kg\m3) to both proposed wing model and the main aircraft wing model. The results are shown an improvement in aerodynamic parameters including increment lift coefficient to (0.22%-5.95%), reduction drag coefficient to (0.34% - 3.60%), increment wing load efficiency ratio to (2.62% - 7.30%), reduction induct drag coefficient CDi to (7.65% - 13.11%) compared with the main aircraft wing model and achieved an improvement in aircraft flight maneuver abilities and stability controls especially during descent, approach, landing and takeoff with lower speed with shortage runway.
Phenytoin selective electrodes were constructed based on penytoin-phosphotungstate (Ph-PT) complex with different plasticizers; di-butyl phosphate (DBP), tri-butyl phosphate (TBP), di-butyl phthalate (DBPH),and o-nitro phenyl octyl ether (NPOE) phthalate. The electrodes based on DBPH, ONPOE plasticizers gave Narnistain slope which are, 56.4 and 55.3mV/decade with detection limit of 1.9x10-5 M , 1.8x10-5 and concentration range 10-1 to 10-4 M and pH range 3.0 – 8.0. The electrodes based on TBP and DBP showed non-Nernistain slopes, 40.2,40.5 mV/decade for both plasticizers. Interfering of some cations was investigated and shows no interfering with electrodes response. Potentiometric methods were used for measuring phenytion in
... Show MoreBackground: During the pandemic, Corona virus forced many people, especially students, to spend more time than before on the computer and smartphone to study and communicate. The poor posture of the body may have worse effect on its body parts , most of which is the cervical spine (forward head posture). Objective: To assess the incidence of neck pain and the associated factors among undergraduate medical students related to position during E learning Subjects and Methods: Cross-sectional study was conducted among medical students in three Iraqi universities during 2021. The sample size was 152. Online questionnaire by Google forms sampling method were used to collect the data which was analysed using SPSS 25. Results: The perce
... Show MoreA restrictive relative clause (RRC hereafter), which is also known as a defining relative clause, gives essential information about a noun that comes before it: without this clause the sentence wouldn’t make much sense. A RRC can be introduced by that, which, whose, who, or whom. Givon (1993, 1995), Fox (1987), Fox and Thompson (1990) state that a RCC is used for two main functions: grounding and description. When a RRC serves the function of linking the current referent to the preceding utterance in the discourse, it does a grounding function; and when the information coded in a RRC is associated with the prior proposition frame, the RRC does a proposition-linking grounding function. Furthermore, when a RRC is not used to ground a new di
... Show MoreThis study is the first and new record to the spider Scytodes univittata Simon, 1882 (Araneae:Scytodidae)in Baghdad /Iraq , the spiders Scytodes univittata were collect from province Baghdad in Iraq , genus Scytodes belong to the family Scytodidae it is one of the most family are wide distribution around the world have 6 eyes and are slow moving , the genus Scytodes are known from the names spitting spiders ,.Female Scytodes univittata can be characteristic by :large round cephalothorax length:4.45 mm , abdomen length 3.50, total body length 7.95 mm and V-shaped of fovea, scutela triangle and large with long thin legs femur I have two row of spines then spineless are in IV femur , coloration is yello
... Show MoreSignificant advances in horizontal well drilling technology have been made in recent years. The conventional productivity equations for single phase flowing at steady state conditions have been used and solved using Microsoft Excel for various reservoir properties and different horizontal well lengths.
The deviation between the actual field data, and that obtained by the software based on conventional equations have been adjusted to introduce some parameters inserted in the conventional equation.
The new formula for calculating flow efficiency was derived and applied with the best proposed values of coefficients ψ=0.7 and ω= 1.4. The simulated results fitted the field data.
Various reservoir and field parameters including late
This paper proposes a new method to tune a fractional order PID controller. This method utilizes both the analytic and numeric approach to determine the controller parameters. The control design specifications that must be achieved by the control system are gain crossover frequency, phase margin, and peak magnitude at the resonant frequency, where the latter is a new design specification suggested by this paper. These specifications results in three equations in five unknown variables. Assuming that certain relations exist between two variables and discretizing one of them, a performance index can be evaluated and the optimal controller parameters that minimize this performance index are selected. As a case study, a third order linear time
... Show MoreAbstract
The research aims to study the problem of high production costs and low quality and the use of total quality management tools to detect problems of the high cost of failure and low quality products, diagnosis, and developing appropriate solutions.
To achieve the goal, we studied the overall quality tools and its relationship with the costs and the possibility of improving quality through the use of these tools.
Was limited to these tools and study the relation to the reduction of costs and improving quality have been studied serially by the possibility of the reduction.
To achieve the goal, the study of the concept of total quality management
Traditional accounting takes only one dimension (economic) in calculating the value added of the company, and all other aspects (including environmental and social) are neglected, and despite the emergence of Sustainability Accounting and the interest of companies in preparing sustainability reports, these reports are suffering from many problems, including multiple metrics used in measuring companies (cash, quantity and lavish). In addition, these reports may reach dozens of pages in some companies and this causes the problem (information overload) which affects the qualitative properties of accounting information such as appropriate and relative, which requires the need to find a tool that can measure the Sustainability Unit of
... Show MoreA sense of job security for divorced female teachers is one of the basic and very important requirements for enjoying the mental health that a person needs in order to be positive, balanced and productive. job security is one of the important things that workers must feel not only to ensure interaction and harmony between them and officials, but to ensure their satisfaction and increasing their motivation towards work, as job security is one of the most important indicators of job satisfaction and optimism in life, and it leads to the experience of psychological reassurance, which affects the building of individuals' personalities, the development of their intellectual competence and the identification of their psychological characteristic
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