Papers by Keyword: Factorial Analysis

Abstract: In this study, was investigated the optimization of the factors that significantly influenced the mechanical property improvement of cassava starch nanocomposites through complete factorial design 23. The factors to be analyzed were cassava starch (A), glycerol (B) and modified clay (C) contents. The clay had its surface modified by anion exchange in the presence of a quaternary ammonium salt. The factorial analysis suggested a regression model capable of predicting the optimal mechanical property of the cassava starch biofilm from the maximization of the elastic modulus. The reliability of the regression model was tested by the correlation established with the experimental data through the following statistical analyzes: Pareto graph and response surface. The response surface showed the best combination of factor configurations to achieve the best response and SEM analysis in thermoplastic cassava starch biofilms in both the best and the worst elasticity conditions was performed to visualize the standard of the structure of the biopolymeric matrix in both conditions. The sequence of the degree of statistical significance on the elastic modulus in relation to the effects investigated is therefore C> B> A> BC> AC.

Abstract: The increase of environmental issues awareness has accelerated the utilization of renewable resources like plant fiber to be used as reinforced material in polymer composite. However, there are significant problems of compatibility between the fiber and the matrix due to weakness in the interfacial adhesion of the natural fiber with the synthetic matrices. One of the solutions to overcome this problem is using chemical modification like alkali treatment. In this study, the impact of alkali treatment conditions on short randomly oriented kenaf fiber reinforced polyester matrix composite tensile strength was investigated. The experimental design setting was based on 2 level factorial experiments. Two parameters were selected during alkali treatment process which are kenaf fiber immersion duration (at 30 minute and 480 minute) and alkali solution temperature (at 40°C and 80°C). Alkali concentration was fixed at 2% (w/v) and the kenaf polyester volume fraction ratio was 10:90. The composite specimens were tested to determine the tensile properties according to ASTM D638-10 Type I. JOEL scanning electron microscopy (SEM) was used to study the microstructure of the material. The result showed that alkali treatment conditions setting do have the impact on tensile strength of short randomly oriented kenaf polyester composite. The interaction factors between immersion time and temperature was found to have prominent factors to the tensile strength of composite followed by the immersion time factor.

Abstract: With the accelerating process of urbanization, heavy metal pollution problem is getting worse. In order to find out the state of heavy metal pollution in urban surface soils, we divided the city into different functional areas, and conducted the surface soil sampling, heavy metals analysis, and urban heavy metal pollution of surface soil data gathering. On this basis, evaluate the state of heavy metal pollution using Nemerow index, and analyze the source of heavy metal pollution. Evaluation and analysis process is simple and reasonable, is conducive to engineering applications, and also for environmental management department of the scientific decisions.

Abstract: Based on the mechanism of mass and heat transfer of the particles and air in drying tube, the mathematics model of pneumatic drying process was established which referred to straw fuel in straight horizontal tube, and the equations were solved by Runge-Kutta integration method. Then, by analyzing the thermal factors of gas flow drying，the most important factor in gas flow drying on straw fuel was summed up which was the mass of hot air. The method of orthogonal experimental design was used to analyze the whole process of gas flow drying, and primary and secondary roles led to the conclusion, which were the mass of hot air first , the equivalent diameter of the fuel granule and the temperature of hot air.

Abstract: The design of experiments (DOE) is a very useful tool to design and analyze complicated industrial design problems. They help to understand the variability a manufacturing process by investigating which parameters and their interaction mainly affect the output repeatability. As a consequence, it enables to individuate the combination of parameters that optimize the output avoiding misinterpretation that can be due to the singularity of the experimental data. In this study the factorial analysis was used to investigate the effects of the major geometrical parameters on the shape of the force-displacement curve of the self piercing riveting (SPR) process. A full two level three-factorial design (23) was completed, three-way interaction was not considered. The statistical analysis was carried out at four different points of the force-rivet displacement curve. These points can be considered critical since they limit the four steps in which the process is commonly divided for studying purpose. The experimental data did not fulfil the required design points, the missing points were obtained by a finite element model of the riveting process, which furnished the force versus the rivet run.