186 research outputs found

    The Information System by Uncertainty Theory

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    The theories of uncertainty are very useful to treatwith mathematics that needs to address and in providing aflexible model to elaborate uncertainty and vagueness involvedin decision making. In this paper, we used the informationsystem by converting the information system to the triangularfuzzy number matrix; into its membership function and bycomputing the relation matrices to take the suitable decisionwith degree. In this paper, we also introduced an application inreal life

    Pathological issues of the Finite Element Method

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    157 σ.Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.)This master thesis aims to investigate some Pathological issues of the FEM on static analysis of plane problems. Its objective is to analyze the results of the plane elements and find a way to improve them in simple and efficient way. Four types of plane elements are being discussed; Constant Strain Triangle CST, Linear Strain Triangle LST, Bilinear Quadratic element Q4 and Quadratic Quadrature element Q8. Each type has its advantages and defects. Some locking problems as shear locking and compressibility locking are discussed too. They are the main reasons of the wrong results of the plane elements. How the choice of the numerical integration can affect the analysis and overcome the shear locking problem. An illustrative example is analyzed to understand the locking problems. Computer program for each example has been written and included in the appendices. The program used for the analysis is MatLab.Ahmed Shokr

    Utilization of Synthesized Nano-Zinc Oxide in Yellow Basic Dye Decontamination from Industrial Wastewater

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    ZnO nanorod has been successfully synthesized through the reduction of Zinc chloride salt with ammonia solution in the presence of triethanolamine (TEA) as surfactant agent via hydrothermal technique. The properties of the produced material were determined using different characterization techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared spectrum (FTIR). The results showed that the asprepared ZnO are rod- like morphologies at pH equal to 10. The synthesized nano rod-zinc oxide was employed asadsorbent agent for basic yellow 28 dye decolorization from polluted industrial wastewater. The synthesized nano-ZnO was achieved 93.26% dye decolorization affinity with in 60minutes. The variation in the different processing parameters on the dye sorption process was elucidated using batch technique. The increment in both the dye solution pH and its  temperature was association with decline in the decolourization process. The optimum nano-zinc oxide dosage was recorded to be equal to 10 g/L. The adsorption data at equilibrium were analyzed using Langmuir, Freundlich and Temkin equilibrium isotherms. The experimental results confirmed the applicability of synthesized nano-zinc oxide as adsorbent agent for dye decontamination from polluted wastewater.Keywords: nano-zinc oxide, dye decolourization, sorption parameters

    Stellar parameters of Be stars observed with X-shooter

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    Aims. The X-shooter archive of several thousand telluric star spectra was skimmed for Be and Be-shell stars to derive the stellar fundamental parameters and statistical properties, in particular for the less investigated late type Be stars, and the extension of the Be phenomenon into early A stars. Methods. An adapted version of the BCD method is used, utilizing the Balmer discontinuity parameters to determine effective temperature and surface gravity. This method is optimally suited for late B stars. The projected rotational velocity was obtained by profile fitting to the Mg ii lines of the targets, and the spectra were inspected visually for the presence of peculiar features such as the infrared Ca ii triplet or the presence of a double Balmer discontinuity. The Balmer line equivalent widths were measured, but due to uncertainties in determining the photospheric contribution are useful only in a subsample of Be stars for determining the pure emission contribution. Results. A total of 78 Be stars, mostly late type ones, were identified in the X-shooter telluric standard star archive, out of which 48 had not been reported before. The general trend of late type Be stars having more tenuous disks and being less variable than early type ones is confirmed. The relatively large number (48) of relatively bright (V > 8.5) additional Be stars casts some doubt on the statistics of late type Be stars; they are more common than currently thought: The Be/B star fraction may not strongly depend on spectral subtype.Comment: Accepted for publication in A&

    Allergic bronchopulmonary aspergillosis as a cause of bronchial asthma in children

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    Background: Allergic bronchopulmonary aspergillosis (ABPA) occurs in patients with asthma and cystic fibrosis. When aspergillus fumigatus spores are inhaled they grow in bronchial mucous as hyphae. It occurs in non immunocompromised patients and belongs to the hypersensitivity disorders induced by Aspergillus. Objective: To diagnose cases of allergic bronchopulmonary aspergillosis among asthmatic children and define the association between the clinical and laboratory findings of aspergillus fumigatus (AF) and bronchial asthma. Methods: Eighty asthmatic children were recruited in this study and divided into 50 atopic and 30 non-atopic children. The following were done: skin prick test for aspergillus fumigatus and other allergens, measurement of serum total IgE, specific serum aspergillus fumigatus antibody titer IgG and IgE (AF specific IgG and IgE) and absolute eosinophilic count. Results: ABPA occurred only in atopic asthmatics, it was more prevalent with decreased forced expiratory volume at the first second (FEV1). Prolonged duration of asthma and steroid dependency were associated with ABPA. AF specific IgE and IgG were higher in the atopic group, they were higher in Aspergillus fumigatus skin prick test positive children than negative ones .Wheal diameter of skin prick test had a significant relation to the level of AF IgE titer. Skin prick test positive cases for aspergillus fumigatus was observed in 32% of atopic asthmatic children. Conclusion: ABPA occurs in 1/3 of atopic asthmatic children and is related to the duration and severity of asthma.Keywords: Aspergillosis, bronchial asthma, childrenEgypt J Pediatr Allergy Immunol 2012;10(2):95-10

    Formulation of Synthesized Zinc Oxide Nanopowder into Hybrid Beads for Dye Separation

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    The sol-gel prepared zinc oxide nanopowder was immobilized onto alginate-polyvinyl alcohol polymer blend to fabricate novel biocomposite beads. Various physicochemical characterization techniques have been utilized to identify the crystalline, morphological, and chemical structures of both the fabricated zinc oxide hybrid beads and their corresponding zinc oxide nanopowder. The thermal stability investigations demonstrate that ZnO nanopowder stability dramatically decreased with its immobilization into the polymeric alginate and PVA matrix. The formulated beads had very strong mechanical strength and they are difficult to be broken up to 1500 rpm. Moreover, these hybrid beads are chemically stable at the acidic media (pH < 7) especially within the pH range of 2–7. Finally, the applicability of the formulated ZnO hybrid beads for C.I. basic blue 41 (BB41) decolorization from aqueous solution was examined

    Utilization of Synthesized Nano-Zinc Oxide in Yellow Basic Dye Decontamination from Industrial Wastewater

    Get PDF
    ZnO nanorod has been successfully synthesized through the reduction of Zinc chloride salt with ammonia solution in the presence of triethanolamine (TEA) as surfactant agent via hydrothermal technique. The properties of the produced material were determined using different characterization techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared spectrum (FTIR). The results showed that the as prepared ZnO are rod- like morphologies at pH equal to 10. The synthesized nano rod-zinc oxide was employed as adsorbent agent for basic yellow 28 dye decolorization from polluted industrial wastewater. The synthesized nano-ZnO was achieved 93.26% dye decolorization affinity with in 60minutes. The variation in the different processing parameters on the dye sorption process was elucidated using batch technique. The increment in both the dye solution pH and its temperature was association with decline in the decolorization process. The optimum nano-zinc oxide dosage was recorded to be equal to 10 g/L. The adsorption data at equilibrium were analyzed using Langmuir, Freundlich and Temkin equilibrium isotherms. The experimental results confirmed the applicability of synthesized nano-zinc oxide as adsorbent agent for dye decontamination from polluted wastewater
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