Flutter is a phenomenon resulting from the interaction between aerodynamic and structural dynamic forces and may lead to a destructive instability. The aerodynamic forces on an oscillating airfoil combination of two independent degrees of freedom have been determined. The problem resolves itself into the solution of certain definite integrals, which have been identified as Theodorsen functions. The theory, being based on potential flow and the Kutta condition, is fundamentally equivalent to the conventional wing-ection theory relating to the steady case. The mechanism of aerodynamic instability has been analyzed in detail. An exact solution, involving potential flow and the adoption of the Kutta condition, has been analyzed in detail. The solution is of a simple form and
is expressed by means of an auxiliary parameter K. The use of finite element modeling technique and unsteady aerodynamic modeling with the V-G method for flutter speed prediction was used on a fixed rectangular and tapered wing to determine the flutter speed boundaries. To build the wing the Ansys 5.4 program was used and the extract values were substituted in the Matlab program which is designed to determine the flutter speed and then predicted the various effects on flutter speed. The program gave us approximately identical results to the results of the referred researches. The following wing design parameters were investigated skin shell thickness, material properties, cross section area for beams, and changing altitude. Results of these calculations indicate that structural mode shape variation plays a significant role in the determination of wing flutter boundary.
To limit or reduce common microbial contamination occurrence in dairy products in general and in soft cheese in particular, produced in locally plants, this study was performed to demonstrate the possibility of implementing HACCP in one of dairy plants in Baghdad city
HACCP plan was proposed in soft cheese production line. A pre-evaluation was performed in soft cheese line production, HACCP Pre-requisites programs was evaluated from its presence and effectiveness. The evaluation was demonstrated risk in each of: Good Manufacturing Practice (GMP) program, evaluated as microbial and physical risk and considered as critical r
... Show MoreAl-Yusifia river was assessed at three sampling stations with study period from Autumn 2010 to the end of Summer 2011. The present investigation was carried out on diversity of fungi and bacteria from Al-Yusifia river, Baghdad city. During the study, a total of 12 fungal genus and 6 bacterial genus were isolated during the year seasons. The dominant fungus at the three stations were Penicillium sp., then Rhizopus and Trichophyton megninii while the dominant bacteria was Escherichia coli and Klebsiella sp.
The higher
... Show MoreThis article investigates the relationship between foot angle and jump stability, focusing on minimizing injury risk. Here are the key points: Importance: Understanding foot angle is crucial for improving jump stability, athletic performance, and reducing jump-related injuries like ankle sprains. Ideal Foot Angle: Research suggests a forward foot angle of around 15 degrees might be ideal for many people during jumps. This angle distributes forces evenly across the foot, lowers the center of gravity, and provides more surface area for pushing off the ground. Factors Affecting Ideal Angle: The optimal angle can vary depending on the type of jump (vertical vs. long jump), fitness level, and personal preference. Incorrect Foot Angles: Landing w
... Show MoreNeed organizations today to move towards strategic thinking which means analyzing situations faced by particular challenges of change in the external environment, which makes it imperative for The Organization That to reconsider their strategies and orientations and operations, a so-called re-engineering to meet those challenges and pressures, to try to achieve improvement root in the installation of the organization and methodscompletion of its work towards achieving high levels of performance and that is reflected to achieve its objectives, and this is what aims to Current search to deal with implications characteristics of strategic thinking in the stages of application re-engineering business of the company General Industries
... Show MoreA field study was conducted on a sample of the public in Baghdad to study the audience's exposure to the television promotion of pharmaceutical products and their trends in order to determine the rate of exposure of the public to the television promotion of pharmaceutical products according to the theory of uses and rumors and to determine the public's attitudes towards television promotion of pharmaceutical products. A survey of (25) a questions was distributed to a sample of the audience of 150 people. The statistical program SPSS was used to unload the data and for the calculation of frequencies and percentages and correlation coefficients. The research reached several results, Most importantly, the television promotion is well receiv
... Show MoreMunicipal solid waste is one of the most important environmental problems in the world and is an important source of environmental pollution and contributes significantly to the pollution of the basic environmental elements of soil, water and air. The management of municipal waste in general is a process of monitoring, collection, treatment or recycling if possible or disposal of waste. This term is used for waste produced by some human activities. States provide this process to mitigate the negative effects of waste on the environment, health and appearance of the city. It is possible to find solutions to the problem of solid waste and make it an important source of income and contribute to securing employment oppor
... Show MoreFor a connected topological space M we define the homeomorphism and period noncoincidence indices of M, each of them is topological invariant reflecting the abundance of fixed point free self homeomorphisms and periodic point free self maps defined on M respectively. We give some results for computing each of these indices and we give some examples and some results relating these indices with Hoffman index.
In this paper we study the notion of preradical on some subcategories of the category of semimodules and homomorphisms of semimodules.
Since some of the known preradicals on modules fail to satisfy the conditions of preradicals, if the category of modules was extended to semimodules, it is necessary to investigate some subcategories of semimodules, like the category of subtractive semimodules with homomorphisms and the category of subtractive semimodules with ҽҟ-regular homomorphisms.