49 research outputs found

    Designing Advanced Reliability Testing Mathematical Model for Modern Products

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    The modern era is the age of science, technology and at the same time it is the age of competition. The advancement of new technology and increased global competition have emphasized the importance of product strength and reliability estimation. As a result, producers and manufacturers must now verify the strength and reliability of their products prior to releasing them to the market. In the past, reliability data analysis was a critical tool for this purpose. Traditionally, reliability data analysis entails quantifying these life characteristics through the examination of failure data. However, in many situations, obtaining such failure data has been extremely difficult, if not impossible, due to the length of time between designing and releasing a product, and the difficulty of designing a product that will last a long period due to its continuous use and operation. Faced with this challenge, reliability statisticians developed a technique called Accelerated Reliability Testing to rapidly determine the reliability and life characteristics of products. This technique increases product reliability and identifies when and how a product will fail in its intended environment. In the present work, we plan to investigate these mathematical reliability models to determine the costs associated with the various product guarantees. If component lifetimes follow the power-function distribution, the problem is examined under increasing stress using percent failure censoring. The method is referred as a process that applies accelerated testing to estimate the cost of age-replacement for goods sold under warranty. Additionally, a mathematical illustration is presented to illustrate the results

    Sustainable energy saving alternatives in small buildings

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    Day lighting significance in architectural designs is well established for enhancing visual comfort, energy-efficiency and low carbon buildings development. Practising the atrium element in the modern architectures has been increasingly popular in recent years because of the fact that the transitional space with good environmental elements can improve the quality of the buildings and reduce extra energy utilisation. The present study explores the advantages and effectiveness of the atrium on the energy performance of small buildings, a case study of ‘The Azuma Row House’. Based on local micro-climate data Autodesk Ecotect Analysis was performed to calculate the daylight factors and the energy demand of the building. A comparison was made with atrium and without atrium in the building to evaluate overall energy savings. The results show a higher annual heating energy demand with atrium 3443 kWh compared without atrium 2526 kWh. The annual cooling energy demand without atrium 2516 kWh is significantly greater than with atrium 912 kWh. The total energy requirements under no atrium case is about 5042 kWh which is considerably higher than the total annual energy demand with atrium 4355 kWh. The total amount of energy saved is about 15.7% per year by introducing the sunlight through the atrium. Along with the increasing issue of the energy crisis, environmental problem and the beautiful design of atrium, the development of atrium in modern architecture designing is feasible to have a good future

    Evolutionary Integrated Heuristic with Gudermannian Neural Networks for Second Kind of Lane–Emden Nonlinear Singular Models

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    In this work, a new heuristic computing design is presented with an artificial intelligence approach to exploit the models with feed-forward (FF) Gudermannian neural networks (GNN) accomplished with global search capability of genetic algorithms (GA) combined with local convergence aptitude of active-set method (ASM), i.e., FF-GNN-GAASM to solve the second kind of Lane–Emden nonlinear singular models (LE-NSM). The proposed method based on the computing intelligent Gudermannian kernel is incorporated with the hidden layer configuration of FF-GNN models of differential operatives of the LE-NSM, which are arbitrarily associated with presenting an error-based objective function that is used to optimize by the hybrid heuristics of GAASM. Three LE-NSM-based examples are numerically solved to authenticate the effectiveness, accurateness, and efficiency of the suggested FF-GNN-GAASM. The reliability of the scheme via statistical valuations is verified in order to authenticate the stability, accuracy, and convergence

    Numerical evaluation of thermal comfort in traditional courtyards to develop new microclimate design in a hot and dry climate

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    The growing interest in thermal comfort of outdoor environments yields in different analysis on courtyards as a common space between urban and architectural scales. However, there is a limited knowledge regarding the microclimatic behavior of such spaces. Using ENVI-met simulations, this paper aims to numerically discuss the thermal performance of different configurations of traditionally designed courtyards in Shiraz, Iran, which experiences hot summers and cold winters. The geometrical effects such as orientation and H/W (height to width ratio) of courtyards are considered as potential parameters to improve the microclimatic conditions. In this paper, PMV and UTCI are used as thermal comfort indices. The obtained results indicate mean radiant temperature and wind speed as the most effective parameters for thermal comfort of courtyards. In addition, the aforementioned geometrical parameters might not be able to solely create a desirable condition, but they could significantly improve the thermal comfort of courtyards during summer and winter. To achieve a desirable thermal comfort level, the results suggest using configurations of a high H/W rate and southward orientation in order to obtain better shading during summer as well as allowing the solar radiation in while regulating the wind speed in winter

    Assessing the energy performance of modern glass facade systems

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    The design and construction of the building envelope have a significant effect on the energy performance of buildings because the building envelope physically separates the exterior from the interior environment. The use of glass as a component of the building envelope has been significantly growing since its initial introduction as a building material. The glass is necessary for aesthetics, ventilation, and daylight. Despite the many benefits to the building, the glazing still provides the lowest insulating value. Of all envelope components, windows and skylights represent major sources of thermal losses and gains which impact the thermal comfort in buildings. Therefore, window size, type, and design are the most important consideration for reducing the need for space heating and cooling. This study investigates the thermal performance and the effectiveness of various modern glass facade systems to improve building efficiency levels. The main objectives of this study are to provide a comparison and evaluation of glazing systems and to establish guidelines for energy-efficient envelope design that provide architects and designers with a basic framework for the selection of the most appropriate glazing systems. It has been noted that the spectrally selective system and the electrochromic glazing system show high energy efficiency compared to other tested glazing systems

    Ramanujan-type series for [one divided by pi] with quadratic irrationals : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Mathematics at Massey University, Albany, New Zealand

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    In 1914, Ramanujan discovered 17 series for 1= , 16 are rational and one is irrational. They are classi ed into four groups depending on a variable ` called the level, where ` = 1, 2, 3 and 4. Since then, a total of 36 rational series have been found for these levels. In addition, 57 series have been found for other levels. Moreover, 14 irrational series for 1= were found. This thesis will classify the series that involve quadratic irrationals for the levels ` 2 f1; 2; 3; 4g. A total of 90 series are given, 76 of which are believed to be new. These series were discovered by numerical experimentations using the mathematical software tool \Maple" and they will be listed in tables at the end of this thesis

    Recovery and Stabilization of Anthocyanins and Phenolic Antioxidants of Roselle (Hibiscus sabdariffa L.) with Hydrophilic Deep Eutectic Solvents

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    Deep eutectic solvents (DESs) have got huge interest as new green and sustainable solvents for the extraction of bioactive compounds from plants in recent decades. In the present study, we aimed to investigate the effectiveness of hydrophilic DES for the extraction of anthocyanin and polyphenol antioxidants from Roselle. A natural hydrophilic DES constituted of sodium acetate (hydrogen bond acceptor) and formic acid (hydrogen bond donor) designed to evaluate the total phenolic compound (TPC), total flavonoid (TFC), total anthocyanin (TACN), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP) values of Roselle. Distilled water, 70% ethanol, and 80% methanol used as conventional solvents for comparison. The results indicated that the DES prepared in molarity ratio (SAFAm) was the most efficient. Subsequently, this prominent DES selected for the optimization and the optimum extraction conditions were 1:3.6 molarity ratio, 0% additional water, and 10 mL solvent. TPC, TFC, TACN, FRAP, and DPPH radical scavenging at the optimum point were 233.26 mg GAE/g, 10.14 mg ECE/g, 10.62 mg D3S/g, 493.45 mmol ISE/g, and 343.41 mmol TE/g, respectively. The stability tests showed that anthocyanins were more stable in SAFAm. These findings revealed that SAFAm is an effective green solvent for the extraction of polyphenols from various plants

    Utilization of eggshell membrane and olive leaf extract for the preparation of functional materials

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    2-s2.0-85104106624Eggshell membrane (ESM) is a natural proteinaceous by-product of the food industry, especially in the pasteurized egg industry, resulting in the availability of much discarded egg waste. In the literature, eggshell (ES) and ESM usage for their adsorbent properties to remove various organic and inorganic hazardous chemicals, especially from wastewater, has gained interest. In addition, agricultural (olive leaf) and food industry (eggshell and eggshell membrane) waste can together be valorized to produce value-added functional products. This study’s objective was to evaluate the eggshell membrane’s loading capacity for bioactive compounds obtained from olive leaf extract (OLE) in order to prepare functional biomaterial. In this study, waste eggshell membranes were used to adsorb the phenolic compounds from olive leaf extract to design functional biomaterials. Using the foam separation method, both separation of the eggshell membrane and adsorption of bioactive compounds to the eggshell membrane were achieved simultaneously. The characterization studies showed that OLE was successfully adsorbed to the eggshell membrane. Cytotoxicity and antimicrobial studies showed that prepared OLE-loaded membranes were functional materials with bioactive properties. In conclusion, ESM was determined as a promising protein in the production of functional antioxidative and antimicrobial food or dietary supplement after the adsorption of bioactive olive leaf polyphenols. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.NC 27411 National Institute of Food and Agriculture, NIFA King Saud University, KSU: NC.X337-5-21-170-1, NC.X341-5-21-170-1Acknowledgments: The participation of the authors Turki M. S. Aldawoud and Charis M. Galanakis in this work was supported by the Researchers Supporting Project number (RSP-2021/197) of King Saud University, Riyadh, Saudi Arabia. Author (S.A.I.) would also like to acknowledge the support of the Agricultural Research Station at North Carolina Agricultural and Technical State University (Greensboro, NC 27411, USA). This research was funded, in part, by grants (project Number NC.X337-5-21-170-1 and NC.X341-5-21-170-1) from the National Institute of Food and Agriculture (NIFA). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of NIFA.The participation of the authors Turki M. S. Aldawoud and Charis M. Galanakis in this work was supported by the Researchers Supporting Project number (RSP-2021/197) of King Saud University, Riyadh, Saudi Arabia. Author (S.A.I.) would also like to acknowledge the support of the Agricultural Research Station at North Carolina Agricultural and Technical State University (Greensboro, NC 27411, USA). This research was funded, in part, by grants (project Number NC.X337-5-21-170-1 and NC.X341-5-21-170-1) from the National Institute of Food and Agriculture (NIFA). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of NIFA.Funding: The participation of the authors Turki M. S. Aldawoud and Charis M. Galanakis in this work was supported by the Researchers Supporting Project number (RSP-2021/197) of King Saud University, Riyadh, Saudi Arabia. Author (S.A.I.) would also like to acknowledge the support of the Agricultural Research Station at North Carolina Agricultural and Technical State University (Greensboro, NC 27411, USA). This research was funded, in part, by grants (project Number NC.X337-5-21-170-1 and NC.X341-5-21-170-1) from the National Institute of Food and Agriculture (NIFA). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of NIFA
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