Silas Oseme Okuma; Martins Ufuoma Eki; John Damilola Oluwafemi; Chukwuekum Orumgbe
Abstract
The most desired strength value in any welding process is an excellent Ultimate Tensile Strength (UTS) of the weld in respect to the parent metal. Welding process parameters should be monitored and reviewed on a continuous basis due to the increased demand for structural and industrial materials with ...
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The most desired strength value in any welding process is an excellent Ultimate Tensile Strength (UTS) of the weld in respect to the parent metal. Welding process parameters should be monitored and reviewed on a continuous basis due to the increased demand for structural and industrial materials with higher strength weld joints. The goal of this study is to look into the limitations of the investigated industrial firm's existing GMAW welding process parameters used in the welding procedure, and to propose alternative, uniquely designed, and improved process parameters to replace its existing procedure welding protocol, thereby improving weld results by achieving higher Ultimate tensile strength. The proposed process parameters were then compared to available literature, and optimization was performed using the Response Surface Method.Tensile strength was determined on GMAW welding plates of 200mm by 20mm. The RSM Analysis was used to examine the data acquired from the experimental findings, and the results show that the current, voltage, and travel speed had the most significant effect on the ultimate weld strength. Furthermore, the findings show a high link between the actual and predicted ultimate tensile strength. Maximum ultimate tensile strengths of 425, 450, and 475Mpa were attained at welding voltages of 28 v, currents of 240 A, and travel speeds of 0.012 m/s .
Engineering Optimization
Fatin Ishraq; Rumaisa Ahmed; Joytun Nisa Joti
Abstract
3D printing or additive manufacturing is a technology in which 3D objects are printed by depositing a thin layer of material layer-by-layer until a final product is produced. In this research work, it has been focused on the fabrication of a Portable 3D Printer for the manufacturing of sample parts by ...
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3D printing or additive manufacturing is a technology in which 3D objects are printed by depositing a thin layer of material layer-by-layer until a final product is produced. In this research work, it has been focused on the fabrication of a Portable 3D Printer for the manufacturing of sample parts by using Fused Deposition Modeling (FDM) process. The primary process parameters such as nozzle temperature, extrusion speed and fill density in addition to their interactions are studied. It has been observed that these process parameters influence the dimensional accuracy and extrusion time of the part produced by the process of FDM. The main objective of the research work is to create a reliable and cost efficient 3-D printer and to minimize the dimensional variation that usually occurs to plastic parts produced by 3D printers. Cartesian mechanism has been used where the print bed moves in the Z direction and the extruder moves in both the X and Y directions. The 3D printing filament that has been used is made of Poly Lactic Acid or Poly Lactide (PLA). The process involved 3D solid modeling to design, 3D printing with coated adhesive applied on the printing platform, measurement of dimensional variation of the printed parts and statistical analysis. Response Surface Methodology (RSM) based desirability analysis has been employed for optimization of FDM process parameters namely, nozzle temperature, extrusion speed and fill density. Mathematical models were developed and tested for accuracy and extrusion time using Design Expert 11 software for RSM application.
Total quality management and quality engineering
S. Pal; S. Gauri
Abstract
In the real world, the overall quality of a product is often represented partly by the measured values of some quantitative variables and partly by the observed values of some ordinal variables. The settings for the manufacturing processes of such products are required to be optimized considering the ...
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In the real world, the overall quality of a product is often represented partly by the measured values of some quantitative variables and partly by the observed values of some ordinal variables. The settings for the manufacturing processes of such products are required to be optimized considering the quantitative as well as the ordinal response variables. But the simultaneous optimization of the quantitative and the ordinal response variables are rarely attempted by the researchers. In this paper, a new approach for simultaneous optimization of quantitative and ordinal responses are presented, which are developed by integrating multiple regression techniques, ordinal logistic regression technique, and Taguchi’s Signal-to-Noise Ratio (SNR) concept. The effectiveness of the proposed method is evaluated by analyzing two experimental data sets taken from the literature. The comparison of results reveals that the proposed method leads to the best optimal solution with respect to the total SNR as well as the Mean Square Error (MSE) of individual responses
Engineering Optimization
A. H. Niknamfar; H. Esmaeili
Abstract
Nanotechnology deals with studies of phenomena and manipulation on elements of matter at the atomic, molecular and macromolecular level (rangefrom1to100nm), where the properties of matter are significantly different from properties at larger scales of dimensions. Nanotechnology is science, engineering, ...
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Nanotechnology deals with studies of phenomena and manipulation on elements of matter at the atomic, molecular and macromolecular level (rangefrom1to100nm), where the properties of matter are significantly different from properties at larger scales of dimensions. Nanotechnology is science, engineering, and technology conducted at the nanoscale, which is about 1 to 100 nm where nano denotes the scale range of 10-9 and nanotechnology refers the properties of atoms and molecules measuring thoroughly 0.1 to 1000 nm. Nanotechnology is highly interdisciplinary as a field, and it requires knowledge drawn from a variety of scientific and engineering arenas. There are two main types of approaches to nanotechnology: the first approach is Top-down and another one is Bottom-up approach. The Top-down approach involves taking layer structures that are either reduced down size until they reach the nano-scale or deacon structured into their composite parts. This paper aims to deal with Top-down approach in order to utilize Biopolymer nanoparticles for Creating Antimicrobial for chicken feed so that the live average time of chicken will be increased noticeably by using max-min optimization approach. Finally, the applicability of the proposed approach and the solution methodologies are demonstrated in three steps.
Supply chain management
F. Mokhtari karchegani; H. Shirouyehzad; R. Tavakkoli-Moghaddam
Abstract
The fast changing and dynamic global business environment require companies to plan their entire supply chain from the raw material supplier to the end customer. In this paper, we design an integrated supply chain including multiple suppliers, multiple factories, multiple distributors, multiple customers, ...
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The fast changing and dynamic global business environment require companies to plan their entire supply chain from the raw material supplier to the end customer. In this paper, we design an integrated supply chain including multiple suppliers, multiple factories, multiple distributors, multiple customers, multiple products, and multiple transportation alternatives. A new multi-objective mixed-integer nonlinear programming model is proposed to deal with this facility location-allocation problem. It considers two conflicting objectives simultaneously, and then the problem is transformed into a multi-objective linear one. The first objective function aims to minimize total losses of the supply chain including raw material purchasing costs, transportation costs and establishment costs of factories and distributions. The second objective function is to minimize the sum deterioration rate of end products and raw materials incurred by transportation alternatives. Finally, the proposed model is solved as a single-objective, mixed-integer, programming model applying the Global Criteria Method. We test their model with numerical example and the results indicate that the proposed model can provide a promising approach to fulfill customer demand and design an efficient supply chain.
A. Nikbakhsh; S. A. Gholamian; S. M. Hoseini
Volume 3, Issue 3 , September 2014, , Pages 49-68
Abstract
The Generators used in aerial industries should have the characteristics such as high efficiency, power density and reliability, low weight and volume. Among different generators, permanent magnet synchronous generator adequately satisfied these requirements. In this paper, first the dimensions and other ...
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The Generators used in aerial industries should have the characteristics such as high efficiency, power density and reliability, low weight and volume. Among different generators, permanent magnet synchronous generator adequately satisfied these requirements. In this paper, first the dimensions and other quantities of this generator are calculated through an analytical model. Then using Cuckoo Optimization Algorithm (COA), these quantities are optimized to suit for desirable needs of aerospace systems, in order that the total volume of the generator could be minimized and its efficiency could be maximized. The results of this design for the permanent magnet synchronous generator application in aerospace systems have been satisfactory.
M. Modarres Yazdi; M. Shafiei; S.M. Sahihi Oskooyi
Volume 3, Issue 1 , May 2014, , Pages 11-25
Abstract
Data envelopment analysis (DEA) is a non-parametric analytical methodology widely used in efficiency measurement of decision making units (DMUs). Conventionally, after identifying the efficient frontier, each DMU is compared to this frontier and classified as efficient or inefficient. This thesis introduces ...
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Data envelopment analysis (DEA) is a non-parametric analytical methodology widely used in efficiency measurement of decision making units (DMUs). Conventionally, after identifying the efficient frontier, each DMU is compared to this frontier and classified as efficient or inefficient. This thesis introduces the most productive scale size (MPSS), and anti- most productive scale size (AMPSS), and proposes several models to calculate various distances between DMUs and both frontiers. Specifically, the distances considered in this paper include: (1) both the distance to MPSS and the distance to AMPSS, where the former reveals a unit’s potential opportunity to become a best performer while the latter reveals its potential risk to become a worst performer, and (2) both the closest distance and the farthest distance to frontiers, which may proved different valuable benchmarking information for units. Subsequently, based on these distances, eight efficiency indices are introduced to rank DMUs. Due to different distances adopted in these indices, the efficiency of units can be evaluated from diverse perspectives with different indices employed. In addition, all units can be fully ranked by these indices.
