The city has normal natural state, and the man has a usual movement, change and search for the new .Also, the city has a usual change and transform in its time, place and quality (sizes)structures. The city has a solid memory diving into the past and the future and reflects The real present, and this memory has a timing layers change into real materialistic place making the city has accumulated overlapping circles which is hard to break u , and it broadcasts the lockup timing density ,in which there is no visual record precisely, it is just like((the social record)) that evaluates the un visual relationships between the components and parts of the city (community and form) in a visual quiet exhibition and transform change inside. There is no city on earth stayed as it is in its size and shape, in which both of these are in a continuous change (increase and decrease) and continuous transform. Because all cities lie on urbanization development pressures that is the population growth and become exhibited worldly especially after the Second World War. Thus, the problem lies on the defect of time and place structures of the city that reflects negatively on the quality structures (sizes). Then, the deformed change and growth of the city loses its historical storage and it imitates the growth samples out of it is contexts that can not follow it. The cities are born as an urban organization which it could be formal or communal, and it don’t stay on its size or form which it born upon them. Actually it's suffer from transformation and changing's or both of them and they are caused by the effects of time and place. As a result of these effects the city may be witness (size operation), or change its architectural properties, all this will be study in the theoretical side of the research. The research applied its theory on Baghdad city as a case study. Baghdad so that any other cities as something alive which is born, then witness transformations and changing which causing to it time and place effects, they are effect its size (increase and decrease) according to the time effect (event) that made the change or the place effect, and all above will be search in more details with a historical sequences, and in a descriptive and analytical method during the practical side of the research. For this, the research aims at checking these effects of time and place and its reflection on the quality size of city (area and population) taking the change in size of Baghdad city and its growth through the
Background and objectives: This study aimed at testing the effect of plastic sleeve or barrier, used to cover the guide of the light cure unit to prevent cross-infection, on the shear bond strength and site of bond failure of stainless steel and ceramic orthodontic brackets. Materials and methods: Forty orthodontic brackets; twenty stainless steel and twenty ceramic brackets bonded to forty extracted human maxillary first premolars using light cure adhesive cured with and without the use of a protective plastic barrier on the guide. Comparing the effect of this barrier on the shear bond strength and adhesive remnant index was performed using an independent t-test and Chi-square test. Results: The protective barrier had decreased the shear b
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The dynamical behavior of a two-dimensional continuous time dynamical system describing by a prey predator model is investigated. By means of constructing suitable Lyapunov functional, sufficient condition is derived for the global asymptotic stability of the positive equilibrium of the system. The Hopf bifurcation analysis is carried out. The numerical simulations are used to study the effect of periodic forcing in two different parameters. The results of simulations show that the model under the effects of periodic forcing in two different parameters, with or without phase difference, could exhibit chaotic dynamics for realistic and biologically feasible parametric values.
The aims of this study are to measure the defect rate and analyze the problems of production of ready concrete mixture plant by using Six Sigma methodology which is a business strategy for operations improvement depending basically on the application of its sub-methodology DMAIC improvement cycle and the basic statistical tools where the process sigma level of concrete production in the case study was 2.41 σ.
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The Backstepping Sliding Mode Control is a control technique used for controlling nonlinear systems. In this paper, the performance of the backstepping sliding mode controller schemes for the angular velocity control for a rotary actuator of an angular velocity control system that utilizes a novel hydraulic flow control method called inlet throttling was investigated. For the angular velocity dynamic, a linear state feedback with suitable high gain is designed as the virtual controller, where steady state error can be made arbitrarily small according to the gain value. A time varying sliding variable is then selected based on the designed virtual controller. The resulting control design is robust, and the maximum error of the angular veloci
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A hydroponic experiment was carried out at the College of Agricultural Engineering Sciences - University of Baghdad during the fall season of 2019-2020 in order to improve the quality traits of broccoli grown hydroponically under the modified Nutrient Film Technique (NFT), using an internationally approved standard solution and alternative solution, the plant was enriched with ozone and the foliar application of organic nutrients. The Hydroponic study included two experiments with the standard solution (Cooper's solution) and the alternative solution (ABEER). Both experiments were implemented within the Nested Design with three replications, and both included the gas type in the main plot, which were oxygen and ozone, while the sub-
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