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A Parametric Evaluation of Flexural and Tensile Strength Ratios, and Bundle Stresses of Axial Composites Using Weibull’s Theory
Mohammed Faruqi,
Ankur Patel
Issue:
Volume 2, Issue 6, December 2017
Pages:
99-102
Received:
12 September 2017
Accepted:
8 November 2017
Published:
22 December 2017
Abstract: Weibull theory works well for brittle materials. However, its application to composites is not very clear. The present study is a comparative parametric evaluation of flexural and tensile strength ratios, and fiber bundle stresses of axial composites with brittle fiber bundles. A composite based model that utilizes Weibull’s theory is developed and compared with derived Weibull’s theory for brittle fiber bundles. It was found that the predicted strength ratios and the stresses are of similar magnitude to that of Weibull’s and the model converges to unity for composite materials with little or no variability.
Abstract: Weibull theory works well for brittle materials. However, its application to composites is not very clear. The present study is a comparative parametric evaluation of flexural and tensile strength ratios, and fiber bundle stresses of axial composites with brittle fiber bundles. A composite based model that utilizes Weibull’s theory is developed and...
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The Methods Used in the Automotive Production: Hemming Operations Planning
Sezgin Ersoy,
Ishak Ertugrul,
Ebuzer Aygul
Issue:
Volume 2, Issue 6, December 2017
Pages:
103-106
Received:
28 February 2017
Accepted:
15 April 2017
Published:
10 January 2018
Abstract: Hemming is a method used to combine the metal-based parts in automotive manufacturing. Generally, this method is using as an assembly method for closures as doors, hoods, tailgates and trunk lids in automotive bodies. A compound flanging and hemming die is mounted on a carriage for horizontal movement into and out of alignment with the anvil for successive formation of a flange and impacting the flange into a finished hem. In this work aim is explain to Hemming methods and devices and their planning for manufacturing.
Abstract: Hemming is a method used to combine the metal-based parts in automotive manufacturing. Generally, this method is using as an assembly method for closures as doors, hoods, tailgates and trunk lids in automotive bodies. A compound flanging and hemming die is mounted on a carriage for horizontal movement into and out of alignment with the anvil for su...
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A New Damage Model to Predict Orthotropic Nonlinear Behavior of Woven Glass-Epoxy Composite
Mohammad Kashfi,
Gholamhossein Majzoobi,
Nicola Bonora,
Gianluca Iannitti,
Andrew Ruggiero,
Ehsan Khademi
Issue:
Volume 2, Issue 6, December 2017
Pages:
107-112
Received:
8 June 2017
Accepted:
8 August 2017
Published:
12 January 2018
Abstract: In the present work a new damage model based on continuum damage mechanic was proposed to predict the nonlinear behavior of woven glass fiber composite under tensile test. The composite specimens were fabricated by hand lay-up method and they were put into a temperature and pressure controlled curing chamber. In order to perform the tensile test a universal Instron machine was used with the DIC method to measure the strain field during the tensile test. All orthotropic mechanical properties such as elasticity modulus, Poisson`s ratio and failure strain were calculated from experiment. After tensile test it was observed that the material behavior was brittle elastic however the stress-strain curve was exhibited a nonlinear fashion. The reason of nonlinearity assumed as irreversible damage effect during the test for instance initial void, fiber breakage, matrix cracking, delamination and fibers debonding. A new damage model with four physical meaning constants was proposed to predict the nonlinear behavior of the material. The model was implemented by a user subroutine in MSC MARC finite element software. Additionally the material damage constants were obtained from iterative numerical simulations. Moreover the damage parameters were optimized by Genetic Algorithm. In conclusion the damage model can predict the nonlinear behavior of composite in both warp and weft direction with reasonable agreement in comparing with experiment.
Abstract: In the present work a new damage model based on continuum damage mechanic was proposed to predict the nonlinear behavior of woven glass fiber composite under tensile test. The composite specimens were fabricated by hand lay-up method and they were put into a temperature and pressure controlled curing chamber. In order to perform the tensile test a ...
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The Role of Biotechnology in Food Production and Processing
Balarabe Musa Maryam,
Mohammed Sani Sambo Datsugwai,
Idris Shehu
Issue:
Volume 2, Issue 6, December 2017
Pages:
113-124
Received:
10 March 2017
Accepted:
5 April 2017
Published:
15 January 2018
Abstract: Biotechnology is the use of living systems and organisms to develop or make useful products, or any technological applications that uses biological systems, living organisms or derivatives thereof, to make or modify products or processes for specific use. Depending on the tools and applications, it often overlaps with the fields of bioengineering and biomedical engineering. Some of the applications were identified in this paper to include biotechnology in food fermentation to enhance properties such as the taste, aroma, shelf-life, texture and nutritional value of food. Biotechnology in the production of enzymes to bring about desirable changes in food, biotechnology in the production of food ingredients; flavours, fragrances, food additives and a range of other high valued-added products, genetically modified starter cultures, genetically modified foods, the use of all these modern technologies in diagnostics for food testing, the role of biotechnology in food production by increasing food production, improved harvesting, storage and nutritional value, better raw materials, better flavour and the production of food containing vaccines, the safety of food produced with biotechnology as well as the risks and benefits of biotechnology in food production.
Abstract: Biotechnology is the use of living systems and organisms to develop or make useful products, or any technological applications that uses biological systems, living organisms or derivatives thereof, to make or modify products or processes for specific use. Depending on the tools and applications, it often overlaps with the fields of bioengineering a...
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Slaking Lime for Restoration and Conservation of Historical Buildings and Materials, Criticism of an Arabic Historical Manuscripts
Sameh Abdelsalam Hassan,
Abdulnaser Abdulrahman Al-Zahrani
Issue:
Volume 2, Issue 6, December 2017
Pages:
125-131
Received:
20 November 2016
Accepted:
13 December 2016
Published:
5 January 2018
Abstract: Slaking lime is an important and effective process for preparing mortars in conservation of historical buildings and archaeological artifacts based on lime. The lime mortars have been widely used since the Roman era, and lime became one of the important materials for conservation and restoration process to keep the authenticity of the historical materials and sustainability. In many cases, some conservators use black and white cement separately or mix with lime in conservation and restoration, or mix gypsum with lime. They think that will improve the strength of mortars, but all those procedures give bad results on the properties of the mortars, and cause irreversible deterioration for historical materials in both layers and surfaces. Through the mentioned problems, we should go back to historical documents to identify the best method for slaking process to get best results in any intervention needs lime mortars. So we depend on three historical resources from 13th A. H century the first historical manuscript entitled "message in architecture) preserved in king Saud university No.3392 without any previous criticism, the second European historical book entitled" all kinds of Roman cement) translated to Arabic in 1829 AD, the third Arabic book entitled" Summary of ideas in architecture), those resources presented all methods of slaking to give information for researchers to evaluate slaking process after experimental studies which depend on several factors, the main target of the research is to provide conservators with information about slaking process for preparing mortars with good properties in all conservation interventions in artefacts and historical buildings.
Abstract: Slaking lime is an important and effective process for preparing mortars in conservation of historical buildings and archaeological artifacts based on lime. The lime mortars have been widely used since the Roman era, and lime became one of the important materials for conservation and restoration process to keep the authenticity of the historical ma...
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