The field of structural optimization (optimal design) has grown rapidly over the past decades with many different optimization methods that could be used to produce a structure of minimum weight. This research deals with two aspects, in the first, a general numerical technique based on the finite element analysis and it suggests to investigate the preliminary behavior of metal stiffened plate under action of static load environment. The technique was included a finite element model of the structures using high- order isoparimetric plate elements to be used to create a certain models to obtain their optimum design. The models are characterized such that, each model is builded using different types of stiffener configuration. The second aspect was concerned with the investigation of the optimum design configuration of the structures. The optimization techniques used is called Morphing Evolutionary Structural Optimization (MESO). The Morphing ESO was examined in this research to be applied on stiffened plate structures. The Morphing ESO is based on the simple concept that by slowly removing efficient material from a structure, the residual shape evolves in the direction of making the structure better. The mathematical representation of this method is accomplished in this thesis with full programming and modification required being applicable to a new structure with a new condition. Where the thickness of the plate and stiffeners, and the stiffener height are the design variable. While the objective of the optimization is the structure weight and inequality constraints are the maximum Von Misses stress required for each structure.
Dam and powerhouse operation sustainability is a major concern from the hydraulic engineering perspective. Powerhouse operation is one of the main sources of vibrations in the dam structure and hydropower plant; thus, the evaluation of turbine performance at different water pressures is important for determining the sustainability of the dam body. Draft tube turbines run under high pressure and suffer from connection problems, such as vibrations and pressure fluctuation. Reducing the pressure fluctuation and minimizing the principal stress caused by undesired components of water in the draft tube turbine are ongoing problems that must be resolved. Here, we conducted a comprehensive review of studies performed on dams, powerhouses, a
... Show MoreCuO nanoparticles were synthesized in two different ways, firstly by precipitation method using copper acetate monohydrate Cu(CO2CH13)2·H2O, glacial acetic acid (CH3COOH) and sodium hydroxide(NaOH), and secondly by sol-gel method using copper chloride(CuCl2), sodium hydroxide (NaOH) and ethanol (C2H6O). Results of scanning electron microscopy (SEM) showed that different CuO nanostructures (spherical and Reef) can be formed using precipitation and sol- gel process, respectively, at which the particle size was found to be less than 2 µm. X-ray diffraction (XRD)manifested that the pure synthesized powder has no inclusions that may exist during preparations. XRD result
... Show MoreResumen:
El presente trabajo intenta analizar las características del lenguaje jurídico español a cuya estructura se debe su complejidad. A la vez, damos una descripción detallada de sus rasgos morfosintácticos, léxico-semánticos y estilísticos. En ningún momento, pretendemos fijar unas pautas o normas para la traducción de este lenguaje que requiere unos previos conocimientos jurídicos y cierta preparación para proceder a realizar esta tarea. Nuestra intención es, simplemente, ofrecer al lector árabe una pequeña visión de lo difícil que es comprender los textos legales españoles hasta para los nativos para imaginarse las posibles dificultades a la hora de iniciar a traducirlos.
The thermal performance of a flat-plate solar collector (FPSC) using novel heat transfer fluids of aqueous colloidal dispersions of covalently functionalized multi-walled carbon nanotubes with β-Alanine (Ala-MWCNTs) has been studied. Multi-walled carbon nanotubes (MWCNTs) with outside diameters of (< 8 nm) and (20–30 nm) having specific surface areas (SSAs) of (500 m2/g) and (110 m2/g), respectively, were utilized. For each Ala-MWCNTs, waterbased nanofluids were synthesized using weight concentrations of 0.025%, 0.05%, 0.075%, and 0.1%. A MATLAB code was built and a test rig was designed and developed. Heat flux intensities of 600, 800, and 1000 W/m2; mass flow rates of 0.6, 1.0, and 1.4 kg/min; and inlet fluid temperatures of 30, 40, an
... Show MoreThe objective of the research is to identify the effect of an instructional design according to the active learning modelsالباحثين in the achievement of the students of the fifth grade, the instructional design was constructed according to the active learning models for the design of education. The research experience was applied for a full academic year (the first & the second term of 2017-2018). The sample consisted of 58 students, 28 students for the experimental group and 30 students for the control group. The experimental design was adopted with partial and post-test, the final achievement test consisted of (50) objectives and essays items on two terms, the validity of the test was verified by the adoption of the Kudoric
... Show MoreThe letters draw clear picture for what had happened in that time it was full of incidents .that incidents had began with the byzantine invation and persioan persecution .later on the Muslins managed to conquest Iraq and Persia .the muslims spread peace and security for the pupils of that area.
Ishuib manged to achieve peace and security to his adherence .he proved that he was one of those who were aunique persons. Because he did his beast to active and revive the general and special life to his adherence. He succeeded to organize the Christian relation ship with the muslims .
He wrote an agreement with muslims .he thought that this Islamic canquest was from allah to die done the mazdism. He said t
... Show Moreتعد اللغة العربية العامة من المواد التي تدرسها الطالبات في الصف الأول في كل أقسام كلية التربية للبنات، وقد لاحظ الباحث إن الطالبات يفتقرن الى التعرف الى معاني كثير من الكلمات التي ترد في المقطوعات الأدبية الشعرية منها والنثرية التي يقدمها أستاذ المادة، وبما إن وقت المحاضرة محدود فأنه لا يسمح بالتعرف الى أفكار الطالبات حول معاني هذه الكلمات وقد يضطر الأستاذ أخيرا الى تقديم المعاني جاهزة للطالبات من اجل
... Show MoreIn this work, a ceramic model has obtained from Iraqi bentonite as a base material with limited additions of alumina and silica. The selected material can bear temperatures higher than the bearing temperature of bentonite as it achieved tolerance temperatures (1300°C) based on X-ray diffraction patterns. It was found that the addition of alumina and silica led to the occurrence of basic phases such as mullite, quartz, cordierite and feldspar in percentages that depended on the percentage of addition in the mixture and the firing temperature, which was (1000-1300)°C.
Density Functional Theory at the generalized-gradient approximation level coupled with large unit cell method is used to simulate the electronic structure of (II-VI) zinc-blende cadmium sulfide nanocrystals that have dimensions 2-2.5 nm. The calculated properties include lattice constant, conduction and valence bands width, energy of the highest occupied orbital, energy of the lowest unoccupied orbital, energy gap, density of states etc. Results show that lattice constant and energy gap converge to definite values. However, highest occupied orbital, lowest unoccupied orbital fluctuates indefinitely depending on the shape of the nanocrystal.