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Miniaturization and precision are two crucial parameters in modern industry, so the concern of producing a linear drive at variable speed in a very small housing becomes vital. In this paper, a new design of a linear piezoelectric motor and a modification of the current piezo-motor to reduce the frequency range are proposed. The response surface method is used along with finite element method to optimize its parameters. AnsysWorbbench program is used for this purpose. Three different materials are chosen based on the most commonly used materials in industrial application. These materials are then analyzed with four selected parameters (geometrical parameters such as length and width of piezoelectric beam, radius of the driving wheel, and electrical parameters such as the applied voltage). These parameters have a major impact on the response of piezo elements such as size and voltage. A harmonic analysis for different frequency ranges is conducted. It is found that the 9th naturel frequency is suitable for best actuation speed. In addition, the PVDF material is not suitable for this kind of application. Using a motor made from PZT5 material with 32 kHz could produce better behavior. [ABSTRACT FROM AUTHOR]

In injection molding process (IMP), the cooling phase is greatly affected by thermal conductivity as the main factor for conductive heat transfer which represents about 70–80% of the cycle time. Recently, most researchers focus on overcoming the limitation with regard to poor thermal conductivity by developing a new formulation of metal epoxy composite materials as mold inserts for rapid tooling (RT) in IMP. Thus, this research investigates the performance of the cooling efficiency of mold inserts fabricated using epoxy resin mixed with filler particles consisting of aluminum, brass and copper. The transient thermal analysis carried out using the ANSYS simulation software was used to evaluate cooling performance of mold inserts made from various types of filler particles mixed with epoxy. The results obtained will be compared with the results of using P20 mold steel, which is the common material used as mold insert for RT. The simulation results showed that inserting a copper filler particle in the epoxy mold inserts was able to improve the efficiency of cooling time and definitely improve the cycle time of IMP. It is expected that a better mold insert in terms of cooling efficiency could be produced using RT technologies, thus, offering more profit to the molding industries without compromising the quality of molded parts produced. [ABSTRACT FROM AUTHOR]

Today, finding a viable solution for any real world problem focusing on combinatorial of problems is a crucial task. However, using optimisation techniques, a viable best solution for a specific problem can be obtained, developed and solved despite the existing limitations of the implemented technique. Furthermore, population based optimisation techniques are now a current interest and has spawned many new and improved techniques to rectify many engineering problems. One of these methods is the Grey Wolf Optimiser (GWO), which resembles the grey wolf's leadership hierarchy and its hunting behavior in nature. The GWO adopts the hierarchical nature of grey wolfs and lists the best solution as alpha, followed by beta and delta in descending order. Additionally, its hunting technique of tracking, encircling and attacking are also modeled mathematically to find the best optimised solution. This paper presents the results from an extensive study of 83 published papers from previous studies related to GWO in various applications such as parameter tuning, economy dispatch problem, and cost estimating to name a few. A discussion on the properties of GWO algorithm and how it minimises the different problems in the different applications is presented, as well as an analysis on the research trend of GWO optimisation technique in various applications from year 2014 to 2017. Based on the literatures, it was observed that GWO has the ability to solve single and multi-objective problems efficiently due to its good local search criteria that performs exceptionally well for different problems and solutions. [ABSTRACT FROM AUTHOR]