Romeo Marian
University of South Australia, School of Engineering, Faculty Member
This paper presents the development and implementation of a novel robust sensing and measurement system that achieves fine granularity and permits new insights into operation of rotational machinery. Instant angle speed measurements offer... more
This paper presents the development and implementation of a novel robust sensing and measurement system that achieves fine granularity and permits new insights into operation of rotational machinery. Instant angle speed measurements offer a wealth of useful information for complex machines in which the motion is the result of multidimensional, internal, and external interactions. The implementation of the proposed system was conducted on an internal combustion engine. The internal combustion engine crankshaft’s angular velocity is the result of the integration of all variables of motor and resisting forces. The crankshaft angular velocity variation also reflects the interaction between the internal thermodynamic cycle of the engine and the plant it powers. To minimise the number of variables, we used for our experiments an aero piston engine for small air-vehicles—a well-made and reliable powerplant—connected to a propeller. This paper presents the need for a better sensing and meas...
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This paper addresses two NP-hard and strongly related problems in production planning of flexible manufacturing system (FMS), part type selection problem and machine loading problem. Various flexibilities such as alternative machines,... more
This paper addresses two NP-hard and strongly related problems in production planning of flexible manufacturing system (FMS), part type selection problem and machine loading problem. Various flexibilities such as alternative machines, tools, and production plans are considered. Real coded genetic algorithms (RCGA) that uses an array of real numbers as chromosome representation is developed to handle these flexibilities. Hybridizing with variable neighbourhood search (VNS) is performed to improve the power of the RCGA exploring and exploiting the large search space of the problems. The effectiveness of this hybrid genetic algorithm (HGA) is tested using several test bed problems. The HGA improves the FMS effectiveness by considering two objectives, maximizing system throughput and minimizing system unbalance. The resulted objective values are compared to the optimum values produced by branch-and-bound method. The experiments show that the proposed RCGA could reach near optimum soluti...
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The flight performance and maneuverability of Odonata depends on wing shape and aero-structural characteristics, including airfoil shape, wingspan, and chord. Despite the superficial similarity between Odonata planforms, the frequency... more
The flight performance and maneuverability of Odonata depends on wing shape and aero-structural characteristics, including airfoil shape, wingspan, and chord. Despite the superficial similarity between Odonata planforms, the frequency with which they are portrayed artistically, and the research interest in their aerodynamics, those features that are stable and those that are labile between species have not been identified. Studies have been done on 2D aerodynamics over corrugated wings; however, there is limited comparative quantified data on the planforms of Odonata wings. This study was undertaken to explore the scale relationships between the geometrical parameters of photogrammetrically reconstructed wings of 75 Odonata species, 66 from Epiprocta, and 9 from Zygoptera. The wing semi-spans captured in the database range from 24 to 85 mm. By carrying out an extensive statistical analysis of data, we show that the geometrical parameters for the suborder Epiprocta (dragonflies) can ...
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This paper investigates the underlying interplay between the key process parameters of magnetic abrasive finishing (MAF) in improving surface quality. The five process parameters considered were the working gap, rotational speed, feed... more
This paper investigates the underlying interplay between the key process parameters of magnetic abrasive finishing (MAF) in improving surface quality. The five process parameters considered were the working gap, rotational speed, feed rate, abrasive amount, and abrasive mesh when MAFed independently with two abrasive particles—SiC and Al2O3. A series of experiments were conducted with an in-house built MAF tool. Based on the main effect results, a model predicting roughness reduction was developed. Results show that surface quality improvement and the underlying dominant process parameters seem unique to the abrasive type used. When MAFed with SiC, the abrasive quantity and rotational speed influence the most. On the other hand, when MAFed with Al2O3, the trend is different to SiC, i.e., the abrasive mesh size and the working gap are dominant. The prediction model was well validated by independent experiments, indicating its accuracy in estimating and optimizing the process outcome....
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Product Lead Time (PLT) is the period of time from receiving a customer's order to delivering the final product. PLT is an indicator of the manufacturing controllability, efficiency and performance. Due to the explosion in the rate of... more
Product Lead Time (PLT) is the period of time from receiving a customer's order to delivering the final product. PLT is an indicator of the manufacturing controllability, efficiency and performance. Due to the explosion in the rate of technological innovations and the rapid changes in the nature of manufacturing processes, manufacturing firms can bring the new products to market quicker
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Abstra ct: - Implementation of a supply-chain (SC) system has crucial impacts on a company's financial performance. Overall performance of a SC network is influenced significantly by the decisions taken in its production-distribution... more
Abstra ct: - Implementation of a supply-chain (SC) system has crucial impacts on a company's financial performance. Overall performance of a SC network is influenced significantly by the decisions taken in its production-distribution plan which integrates the decisions in production, transport and warehousing as well as inventory management. Thus, one key issue in the current research area of performance evaluation
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Research Interests: Robotics and Fuzzy Logic
Hybrid micro and nanoparticles have become a topic of intense research in recent years. This is due to the special properties of these materials that open new avenues in advanced applications. Herein, we report a novel method for the... more
Hybrid micro and nanoparticles have become a topic of intense research in recent years. This is due to the special properties of these materials that open new avenues in advanced applications. Herein, we report a novel method for the generation of hybrid particles utilising plasma polymerization. Poly (methyl methacrylate) (PMMA) beads were first coated with a thin allylamine based plasma polymer layer. Gold nanoparticles of engineered size and surface structure were then attached in a controlled manner to the plasma polymer coated beads. To generate uniform chemistry on the outermost surface and to preserve the nanotopography, we deposited a 5-10nm thin layer of Acpp. We demonstrated that these particles can be utilized in in vivo models to interrogate important biological phenomena. Specifically, we used them in mice to study the inflammatory and foreign body responses to surface nanotopography. The data strongly indicates that surface nanotopography and chemistry can modulate collagen production and the number of adhering immune cells. The method for generating hybrid particles reported here is solvent free and can open new opportunities in fields such as tissue engineering, drug delivery, biosensors, and regenerative medicine.
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This paper addresses the problem of simultaneously minimising the total costs of the final product produced by systems adopting a JIT approach. A cost which incorporates both the cost of production processes and the cost arising from the... more
This paper addresses the problem of simultaneously minimising the total costs of the final product produced by systems adopting a JIT approach. A cost which incorporates both the cost of production processes and the cost arising from the many potential risks associated with any reduction. A robust genetic approach is proposed in order to optimise the novel mathematical model published in [1]. Genetic operators adopted to improve the genetic search algorithm are introduced and discussed. Experiments are conducted to evaluate the performance of the proposed algorithm and an illustrative example is given. A comparison of the genetic operators used is made by means of evaluating different rates, to define the most suitable rate of crossover and mutation. The findings illustrate the effectiveness of the proposed approach in the JIT system with focus on simultaneous cost-risk reduction.