In this research, polypropylene (PP)–graphite composites were prepared using the melt mixing tech... more In this research, polypropylene (PP)–graphite composites were prepared using the melt mixing technique in a twin-screw extruder. Graphite, multi-walled carbon nanotubes (MWCNT), carbon black (CB), and expanded graphite (EG) were added to the PP in binary, ternary, and quaternary formations. The graphite was used as a primary filler, and MWCNT, CB, and EG were added to the PP–graphite composites as secondary fillers at different compositions. The secondary filler compositions were considered the control input factors of the optimization study. A full factorial design of the L-27 Orthogonal Array (OA) was used as a Design of Experiment (DOE). The through-plane electrical conductivity and flexural strength were considered the output responses. The experimental data were interpreted via Analysis of Variance (ANOVA) to evaluate the significance of each secondary filler. Furthermore, statistical modeling was performed using response surface methodology (RSM) to predict the properties of t...
Despite being inexpensive and robust, steel cord reinforcements are often prone to pose risks to ... more Despite being inexpensive and robust, steel cord reinforcements are often prone to pose risks to user health and safety in some industrial applications such as escalator handrails and rubber conveyor belts. Steel cords can reduce the overall stability and performance of the application over time due to their inherent creep accompanied by cyclic thermal expansion and contraction. In this context, this research focuses on replacing steel cords in some critical thermoplastic polyurethane (TPU) composite applications with continuous sustainable alternate synthetic fibers that possess high specific strength (e.g. carbon, glass, and Kevlar fibers). The first part of this research characterizes the effect of epoxy coating on synthetic fibers alone by studying their mechanical properties before and after modification, whereas the second half of the research involves reinforcing a TPU matrix with raw and epoxy-coated synthetic fibers to fabricate fiber-reinforced composites by compression mo...
One of the opportunities given to third-year students enrolled in the Computer-Aided Design cours... more One of the opportunities given to third-year students enrolled in the Computer-Aided Design course at UOIT is to utilize Design of Experiments and design optimization techniques to determine optimal parameter settings for best performance of an artifact. In the previous course offerings, students determined optimal designs of paper helicopters to optimize flight time, while adhering to a limited number of design constraints. In practice, though, more performance dimensions should be explored for an optimal design. This is particularly true with the design of unmanned air vehicles, which are required to have optimal range (aerodynamic efficiency for higher flight speeds), as well as optimal endurance (ability to stay aloft for extended periods of time, while operating at low speeds and low power). This paper proposes a new assignment that could be used in future offerings of the course, whereby students construct gliders out of ordinary material (Styrofoam, cardboard, etc.), and dete...
Proceedings of the Canadian Engineering Education Association (CEEA), 2018
– This paper introduces a top down, system-engineering approach to develop a quantifiable and s... more – This paper introduces a top down, system-engineering approach to develop a quantifiable and systematic tool, referred to as Design Readiness Level (DRL), to gauge design at each stage of product development. It is developed to facilitate communication between different stockholders of a design project and to address the complexities arising during all the phases of product design, from initiation to completion. The design process as one of the pillars of DRL has been studied thoroughly and is categorized into nine stages to reflect the technical flow in product development. The design stages are iterative at any level from 1 to 9 and have distinctive deliverables at the end of each stage. The deliverables simplify and characterize the assessment of the design from the technical point of view. Developing a comprehensive DRL metrics that encompasses all the stockholders’ perspectives in a design is a work in progress.
ABSTRACT Design engineering educators often create their own term design project problems for the... more ABSTRACT Design engineering educators often create their own term design project problems for their respective courses within an undergraduate engineering curriculum. In particular, upper year projects are more complex and multidisciplinary in nature, requiring several tasks with complex relationships to be completed concurrently. The coupled tasks rely on information from each other, directly affecting the relative difficulty of the design engineering challenge being assigned to students. Quantifying this level of difficulty and project feasibility meaningfully ahead of time is a challenge for instructors, especially given the time constraints of the academic term and expected student knowledge skill level. In this paper, the dynamic response of the design process is analyzed by introducing an unexpected event (a "random disturbance") to some of the design tasks in the process and analyzing its response. The severity of the disturbance will determine what action can be taken to mitigate the impact of unexpected events on the design process as a whole. Using this information, educators have an additional dimension to assess the feasibility (or "doability") of a design project, while students can systematically determine how to reassign resources available to them to reduce the effect of unexpected events in the design process. In this context, a DSM (Design Structure Matrix)-based method for investigating the effect of random disturbances on the outcome of a design project is presented through a third-year engineering design project example at UOIT. 2 BACKGROUND Research over the last several years focused on methods to improve organization of design tasks and to anticipate the effects of design changes. A probability model developed by Gil et al (2006) showed that clients bear higher design rework risk in introducing changes to designs, requiring better planning for uncertainties. Lin et al (2008) developed a model for overlapped iterative development by considering rework due to development errors and corruptions. More recently, Barari and Pop-Iliev (2009) extended a cost due to change model (Prasad, 1996) to understand the role of rigidity and level of changeability of a design, that is, the total cost or difficulty of a desired change. Matrix representation (i.e., DSM) has been used to define the sequence of and the technical relationships between design tasks, and then to find alternative sequences or task definitions to improve the design process (Eppinger et al., 1994). This matrix has been extended to make use of the fully coupled portion of the design process (i.e., WTM) to not only relate dependencies between tasks, but to also define the relative strength of this dependence in terms of a probability of rework of a task, as would result from the completion of a design iteration where the design has not yet satisfied the required specifications and new information becomes available (Smith and Eppinger, 1997). Dynamic analysis techniques have been used to investigate and predict the dynamics of concurrent engineering design using DSM and WTM methods (Kim, 2007; Ong et al., 2003). Further research includes closed-loop control for the design process (Lee et al., 2004), where the feedback gain matrix is chosen based on the slowest converging task in order to expedite it to converge faster and the amount of additional resources needed to do so. The thrust of this paper will be to investigate the convergence of the design process when an unexpected event is introduced into the process. Unpredictable events could include late customer requests or a failure of an agent, causing conflict between aspects of the design that must be resolved.
In this study, the continuous fiber rowing of 12K carbon was electrolytically oxidized by incorpo... more In this study, the continuous fiber rowing of 12K carbon was electrolytically oxidized by incorporating three different types of electrolytes: Ammonium bicarbonate, Sulfuric acid, and Sodium hydroxide at various concentrations. Upon chemical treatment, the fibers were grafted with 3-Aminopropyl-triethoxysilane (APTS), a silane coupling agent, to achieve better interlocking and compatibility with the thermoplastic polyurethane (TPU) matrix. Mechanical properties were analyzed by tensile tests, morphological analysis was carried out through Scanning Electron Microscopy, and spectral analysis was studied through X-ray photoelectron spectroscopy (XPS) characterizations. The results show that 10% sulfuric acid treatment plus APTS grafted carbon fiber/TPU composites showed an average tensile load capacity of 2528 N, about 39% higher than raw carbon/TPU. The morphological analysis provided compelling evidence for the increase in mechanical properties of modified fiber composites as the int...
DEStech Transactions on Engineering and Technology Research, 2017
Conventional rotational foam molding, a modification of the traditional rotational molding (or ro... more Conventional rotational foam molding, a modification of the traditional rotational molding (or rotomolding) process, has lately been brought into being a distinct plastic processing technology. It is characterized with very lengthy processing times and intensive energy consumption. A recently developed and patented, melt extrusion-assisted rotational foam molding process, referred to as Rapid Rotational Foam Molding (RRFM), has been instrumental in increasing the eco-friendliness of rotational molding operations by dramatically reducing processing cycle times and energy consumption. This paper focuses on identifying possible novel processing concepts that would improve further melt extrusion-assisted rotational foam molding operations. Currently, pioneering attempts are being made to successfully apply physical blowing agents (PBAs) in RRFM and thereby substitute commonly used chemical blowing agents (CBAs). Thereby, fabricating a new class of eco-friendly rotationally foam molded i...
The main focus of the research presented in this paper is the investigation of the ability of var... more The main focus of the research presented in this paper is the investigation of the ability of various polyolefin resins to be converted into integral-skin cellular composites by using the rotational foam molding process. Integral-skin foamed rotational moldings are formally denoted as cellular composites ideally having a clearly distinct surface layer of solid skin of uniform thickness that is encapsulating a seamlessly coupled fine-celled foamed core or layer of uniform cell density and distribution. A systematic comparative material characterization study that attempts to derive practical guidelines about determining the roto-foamability of polyolefins that would be useful for rotomolding processors is presented. The study included two experimental methods of characterization, a melt rheology-based and a rotational foam molding processing-based. The experimental results from both implemented characterization methods revealed good agreement. A comprehensive insight into the key pol...
Characterizing the morphology of polymeric foams is crucial for determining their practical appli... more Characterizing the morphology of polymeric foams is crucial for determining their practical applicability. The internal cellular structure of polymeric foams is typically analyzed by 2 D imaging techniques, such as Scanning Electron Microscopy (SEM) and optical microscopy. The problem with these techniques is that their tests are tedious, destructive, and the accuracy of the obtained results is questionable. The objective of this paper is to establish and experimentally verify an efficient 3- dimensional (3 D) Microcomputed-tomography based methodology for reliably estimating and characterizing each of the phases commonly present in multiple types of polymeric foam samples, such as the open, the closed, and the solid phase. A comparative study was carried out between morphology data obtained from 2-dimensional (2 D) analysis and those obtained from 3 D analysis to investigate the reliability of the 2 D analysis results. In this context, the experimental results revealed that by usin...
Volume 4: ASME/IEEE International Conference on Mechatronic and Embedded Systems and Applications and the 19th Reliability, Stress Analysis, and Failure Prevention Conference, 2007
Volume 5: 13th Design for Manufacturability and the Lifecycle Conference; 5th Symposium on International Design and Design Education; 10th International Conference on Advanced Vehicle and Tire Technologies, 2008
Project-based learning is a widely adopted strategy and a preferred pedagogical tool in the under... more Project-based learning is a widely adopted strategy and a preferred pedagogical tool in the undergraduate engineering curriculum. However, design-and-build engineering projects are open-ended, ill-defined, and quite complex so that students often feel quite overwhelmed by the imposed need to solve relatively challenging and practical problems within limited time and resources. Although there are virtually no right or wrong feasible design engineering project solutions, over the years, students’ design project submissions identify a number of students with mediocre design competencies. This indicates that there is a need for developing a pedagogical strategy designed for assisting the students in better preparing for undertaking the challenges of term design engineering projects. Hence, a special series of deliberately designed small-scale “mini” design projects has been developed to serve as “just-in-time” means for building-up the students’ skills required to successfully undertake...
In this research, polypropylene (PP)–graphite composites were prepared using the melt mixing tech... more In this research, polypropylene (PP)–graphite composites were prepared using the melt mixing technique in a twin-screw extruder. Graphite, multi-walled carbon nanotubes (MWCNT), carbon black (CB), and expanded graphite (EG) were added to the PP in binary, ternary, and quaternary formations. The graphite was used as a primary filler, and MWCNT, CB, and EG were added to the PP–graphite composites as secondary fillers at different compositions. The secondary filler compositions were considered the control input factors of the optimization study. A full factorial design of the L-27 Orthogonal Array (OA) was used as a Design of Experiment (DOE). The through-plane electrical conductivity and flexural strength were considered the output responses. The experimental data were interpreted via Analysis of Variance (ANOVA) to evaluate the significance of each secondary filler. Furthermore, statistical modeling was performed using response surface methodology (RSM) to predict the properties of t...
Despite being inexpensive and robust, steel cord reinforcements are often prone to pose risks to ... more Despite being inexpensive and robust, steel cord reinforcements are often prone to pose risks to user health and safety in some industrial applications such as escalator handrails and rubber conveyor belts. Steel cords can reduce the overall stability and performance of the application over time due to their inherent creep accompanied by cyclic thermal expansion and contraction. In this context, this research focuses on replacing steel cords in some critical thermoplastic polyurethane (TPU) composite applications with continuous sustainable alternate synthetic fibers that possess high specific strength (e.g. carbon, glass, and Kevlar fibers). The first part of this research characterizes the effect of epoxy coating on synthetic fibers alone by studying their mechanical properties before and after modification, whereas the second half of the research involves reinforcing a TPU matrix with raw and epoxy-coated synthetic fibers to fabricate fiber-reinforced composites by compression mo...
One of the opportunities given to third-year students enrolled in the Computer-Aided Design cours... more One of the opportunities given to third-year students enrolled in the Computer-Aided Design course at UOIT is to utilize Design of Experiments and design optimization techniques to determine optimal parameter settings for best performance of an artifact. In the previous course offerings, students determined optimal designs of paper helicopters to optimize flight time, while adhering to a limited number of design constraints. In practice, though, more performance dimensions should be explored for an optimal design. This is particularly true with the design of unmanned air vehicles, which are required to have optimal range (aerodynamic efficiency for higher flight speeds), as well as optimal endurance (ability to stay aloft for extended periods of time, while operating at low speeds and low power). This paper proposes a new assignment that could be used in future offerings of the course, whereby students construct gliders out of ordinary material (Styrofoam, cardboard, etc.), and dete...
Proceedings of the Canadian Engineering Education Association (CEEA), 2018
– This paper introduces a top down, system-engineering approach to develop a quantifiable and s... more – This paper introduces a top down, system-engineering approach to develop a quantifiable and systematic tool, referred to as Design Readiness Level (DRL), to gauge design at each stage of product development. It is developed to facilitate communication between different stockholders of a design project and to address the complexities arising during all the phases of product design, from initiation to completion. The design process as one of the pillars of DRL has been studied thoroughly and is categorized into nine stages to reflect the technical flow in product development. The design stages are iterative at any level from 1 to 9 and have distinctive deliverables at the end of each stage. The deliverables simplify and characterize the assessment of the design from the technical point of view. Developing a comprehensive DRL metrics that encompasses all the stockholders’ perspectives in a design is a work in progress.
ABSTRACT Design engineering educators often create their own term design project problems for the... more ABSTRACT Design engineering educators often create their own term design project problems for their respective courses within an undergraduate engineering curriculum. In particular, upper year projects are more complex and multidisciplinary in nature, requiring several tasks with complex relationships to be completed concurrently. The coupled tasks rely on information from each other, directly affecting the relative difficulty of the design engineering challenge being assigned to students. Quantifying this level of difficulty and project feasibility meaningfully ahead of time is a challenge for instructors, especially given the time constraints of the academic term and expected student knowledge skill level. In this paper, the dynamic response of the design process is analyzed by introducing an unexpected event (a "random disturbance") to some of the design tasks in the process and analyzing its response. The severity of the disturbance will determine what action can be taken to mitigate the impact of unexpected events on the design process as a whole. Using this information, educators have an additional dimension to assess the feasibility (or "doability") of a design project, while students can systematically determine how to reassign resources available to them to reduce the effect of unexpected events in the design process. In this context, a DSM (Design Structure Matrix)-based method for investigating the effect of random disturbances on the outcome of a design project is presented through a third-year engineering design project example at UOIT. 2 BACKGROUND Research over the last several years focused on methods to improve organization of design tasks and to anticipate the effects of design changes. A probability model developed by Gil et al (2006) showed that clients bear higher design rework risk in introducing changes to designs, requiring better planning for uncertainties. Lin et al (2008) developed a model for overlapped iterative development by considering rework due to development errors and corruptions. More recently, Barari and Pop-Iliev (2009) extended a cost due to change model (Prasad, 1996) to understand the role of rigidity and level of changeability of a design, that is, the total cost or difficulty of a desired change. Matrix representation (i.e., DSM) has been used to define the sequence of and the technical relationships between design tasks, and then to find alternative sequences or task definitions to improve the design process (Eppinger et al., 1994). This matrix has been extended to make use of the fully coupled portion of the design process (i.e., WTM) to not only relate dependencies between tasks, but to also define the relative strength of this dependence in terms of a probability of rework of a task, as would result from the completion of a design iteration where the design has not yet satisfied the required specifications and new information becomes available (Smith and Eppinger, 1997). Dynamic analysis techniques have been used to investigate and predict the dynamics of concurrent engineering design using DSM and WTM methods (Kim, 2007; Ong et al., 2003). Further research includes closed-loop control for the design process (Lee et al., 2004), where the feedback gain matrix is chosen based on the slowest converging task in order to expedite it to converge faster and the amount of additional resources needed to do so. The thrust of this paper will be to investigate the convergence of the design process when an unexpected event is introduced into the process. Unpredictable events could include late customer requests or a failure of an agent, causing conflict between aspects of the design that must be resolved.
In this study, the continuous fiber rowing of 12K carbon was electrolytically oxidized by incorpo... more In this study, the continuous fiber rowing of 12K carbon was electrolytically oxidized by incorporating three different types of electrolytes: Ammonium bicarbonate, Sulfuric acid, and Sodium hydroxide at various concentrations. Upon chemical treatment, the fibers were grafted with 3-Aminopropyl-triethoxysilane (APTS), a silane coupling agent, to achieve better interlocking and compatibility with the thermoplastic polyurethane (TPU) matrix. Mechanical properties were analyzed by tensile tests, morphological analysis was carried out through Scanning Electron Microscopy, and spectral analysis was studied through X-ray photoelectron spectroscopy (XPS) characterizations. The results show that 10% sulfuric acid treatment plus APTS grafted carbon fiber/TPU composites showed an average tensile load capacity of 2528 N, about 39% higher than raw carbon/TPU. The morphological analysis provided compelling evidence for the increase in mechanical properties of modified fiber composites as the int...
DEStech Transactions on Engineering and Technology Research, 2017
Conventional rotational foam molding, a modification of the traditional rotational molding (or ro... more Conventional rotational foam molding, a modification of the traditional rotational molding (or rotomolding) process, has lately been brought into being a distinct plastic processing technology. It is characterized with very lengthy processing times and intensive energy consumption. A recently developed and patented, melt extrusion-assisted rotational foam molding process, referred to as Rapid Rotational Foam Molding (RRFM), has been instrumental in increasing the eco-friendliness of rotational molding operations by dramatically reducing processing cycle times and energy consumption. This paper focuses on identifying possible novel processing concepts that would improve further melt extrusion-assisted rotational foam molding operations. Currently, pioneering attempts are being made to successfully apply physical blowing agents (PBAs) in RRFM and thereby substitute commonly used chemical blowing agents (CBAs). Thereby, fabricating a new class of eco-friendly rotationally foam molded i...
The main focus of the research presented in this paper is the investigation of the ability of var... more The main focus of the research presented in this paper is the investigation of the ability of various polyolefin resins to be converted into integral-skin cellular composites by using the rotational foam molding process. Integral-skin foamed rotational moldings are formally denoted as cellular composites ideally having a clearly distinct surface layer of solid skin of uniform thickness that is encapsulating a seamlessly coupled fine-celled foamed core or layer of uniform cell density and distribution. A systematic comparative material characterization study that attempts to derive practical guidelines about determining the roto-foamability of polyolefins that would be useful for rotomolding processors is presented. The study included two experimental methods of characterization, a melt rheology-based and a rotational foam molding processing-based. The experimental results from both implemented characterization methods revealed good agreement. A comprehensive insight into the key pol...
Characterizing the morphology of polymeric foams is crucial for determining their practical appli... more Characterizing the morphology of polymeric foams is crucial for determining their practical applicability. The internal cellular structure of polymeric foams is typically analyzed by 2 D imaging techniques, such as Scanning Electron Microscopy (SEM) and optical microscopy. The problem with these techniques is that their tests are tedious, destructive, and the accuracy of the obtained results is questionable. The objective of this paper is to establish and experimentally verify an efficient 3- dimensional (3 D) Microcomputed-tomography based methodology for reliably estimating and characterizing each of the phases commonly present in multiple types of polymeric foam samples, such as the open, the closed, and the solid phase. A comparative study was carried out between morphology data obtained from 2-dimensional (2 D) analysis and those obtained from 3 D analysis to investigate the reliability of the 2 D analysis results. In this context, the experimental results revealed that by usin...
Volume 4: ASME/IEEE International Conference on Mechatronic and Embedded Systems and Applications and the 19th Reliability, Stress Analysis, and Failure Prevention Conference, 2007
Volume 5: 13th Design for Manufacturability and the Lifecycle Conference; 5th Symposium on International Design and Design Education; 10th International Conference on Advanced Vehicle and Tire Technologies, 2008
Project-based learning is a widely adopted strategy and a preferred pedagogical tool in the under... more Project-based learning is a widely adopted strategy and a preferred pedagogical tool in the undergraduate engineering curriculum. However, design-and-build engineering projects are open-ended, ill-defined, and quite complex so that students often feel quite overwhelmed by the imposed need to solve relatively challenging and practical problems within limited time and resources. Although there are virtually no right or wrong feasible design engineering project solutions, over the years, students’ design project submissions identify a number of students with mediocre design competencies. This indicates that there is a need for developing a pedagogical strategy designed for assisting the students in better preparing for undertaking the challenges of term design engineering projects. Hence, a special series of deliberately designed small-scale “mini” design projects has been developed to serve as “just-in-time” means for building-up the students’ skills required to successfully undertake...
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Papers by Remon Pop-iliev