As in previous years we are giving the opportunity to students, apprentices and young engineering professionals to represent Malta at the regional IET Present around the World Competition.
The finalists will compete by giving us the following presentations:
Expressive Piano Music Playing Using a Kalman Filter by Maria Mifsud
Music is a means of communication between three parties – the composer, the performer and the listener, via a music score. Apart from the notes themselves, the score will also contain two types of information. One such type is the symbols that tell the performer how a note or a group of notes should be played. The other type of information envelopes impromptu expressive qualities which the performer decides to include in the performance. The attributes that make a piece of music come to life are changes to the loudness levels (dynamics), note durations (articulation) and tempo.
A system that combines the written expression notation with the phrase structure of the music was designed. The output of such system consists of an interpretation of the music that contains expression in the form of changes to the dynamics, tempo and note articulation. This is achieved through a Kalman filter together with image analysis and performance examples obtained from live recordings of the Beethoven Piano Sonata Op. 2 No. 1. Listening experiments conducted show that expressions introduced by the system match the expected expressions according to the symbolic expressions found in the score as well as the expressions implied by the phrasing structure.
Bone Regeneration; Bridging the Gap with Biodegradable Metals by Christabelle Tonna
More than half a million patients in the United States undergo $2.5 billion worth of procedures annually related to bone defect repair. As a result of enhanced life expectancy, these numbers are predicted to double by the year 2020, making bone the second most transplanted tissue across the world. Scaffolds, bone support structures that mimic the spongy component of bone, are crucial constructs in the modern approach to regenerative medicine, facilitating the surgeon’s task of exploiting the bone’s natural tendency to heal itself. Biodegradable metals have recently gained particular focus for use as bone regeneration scaffolds. Thus, the current work explores the possibility of creating macro-porous iron-based sponges using the polyurethane replication technique. This involves dipping polyurethane foam templates in a slurry containing metal powder and subjecting the foam to a heat treatment in which all organic material is burned-off while the metallic powder is sintered. The scaffolds, which also contain manganese and silver, are expected to offer MRI-compatibility, adequate strength and a controllable corrosion rate. Early results have indicated that powder metallurgy is a promising approach for the creation of scaffolds, as porous structures were fabricated with good densification obtained through the flow of silver via a liquid-phase sintering mechanism.
PIRAC Nitriding of a NiTi Shape Memory Alloy: Augmentation of Degradation Resistance by Matthias Debono
Nickel titanium (NiTi) has lately been given ever increasing consideration for use in both internal and external biomedical applications. In particular, NiTi has gained widespread popularity for its use in self-expanding cardiovascular stents in virtue of its unique inherent characteristics, such as the shape memory effect and its ability to display superelasticity. Unfortunately, despite numerous successful clinical applications, the biocompatibility of NiTi remains controversial as a consequence of its high nickel content (~50 at.%). The release of nickel ions into the human body and surrounding tissues from a NiTi implant raises concerns as it is well documented that Ni promotes toxic, allergenic and potentially carcinogenic effects in vivo. Because of this, NiTi alloys are generally subjected to a surface engineering treatment prior to their use in the human body.
Thus, in view of this, the efficacy of an innovative, low-cost surface engineering technique, that of powder immersion reaction assisted coating (PIRAC), to enhance the degradation resistance, and hence biocompatibility, of NiTi coupons via the formation of a well-adherent titanium nitride (TiN) coating is investigated. The corrosion properties of PIRAC nitrided NiTi coupons will be investigated via electrochemical techniques, including potentiodynamic testing, crevice corrosion testing and electrochemical impedance spectroscopy. Furthermore, the effect of the TiN coating on the shape memory effect and superelasticity properties of NiTi is of particular interest, and thus, this will also be investigated.
Determination of Dielectric Properties of Rocks for Ground Penetrating Radar (GPR) Images by Geraldine Mifsud
Ground Penetrating Radar (GPR) is a method for analysing the sub-surface structure, and is very often used to verify and locate possible buried hazards, to identify the presence of any archaeological sites and also in the investigation of environmental conditions. Additionally, GPR can also be used to provide data for analysis in the preservation and restoration of heritage sites, non-invasively. During GPR measurements, reflected signals of the sub-surface structure are obtained, based on the dielectric contrast of different layers. Data is then post-processed to form images, depicting more information about the sub-surface layers. Post-processing the measured data requires an initial guess of the dielectric properties of the target material/images. In this study, a range of the dielectric properties including the permittivity and the permeability, with their respective uncertainty, of Lower Globigerina Limestone is presented for applications in cultural heritage sites in Malta. Samples were obtained from various boreholes across the island and dielectric measurements were conducted on samples completely saturated in water as well as fully dry samples.
Probabilistic Impact Assessment of Photovoltaic Integration on LV Networks in Malta by Yesbol Gabdullin
To reduce carbon dioxide emissions, the world’s focus is shifting towards clean energy sources. Therefore, the renewable energy resources are expected to grow continuously in the coming decade. Photovoltaic (PV) market is the fastest growing electrical energy generation industry with an average yearly growth of more than 40%. Over the last six years, there has been a rapid development in grid-connected Photovoltaic installations within Malta. Residential-scale PVs can help decarbonising our economies, but can also lead to technical issues, particularly in Low Voltage (LV) Distribution Networks. To quantify these issues, this work proposes a probabilistic impact assessment methodology and presents the first ever study on the Maltese islands on real LV electric networks located on the island of Gozo, considering real smart meter profiles in 15-minute resolution. The stochastic methodology uses a Monte Carlo technique for statistical evaluation of two extreme PV allocation scenarios, i.e. close to and further away from substation. The results analysed during one day with low consumption and high PV generation show that voltage challenges are more constraining while overloading of feeders is negligible. The proactive study illustrates considerably low technical issues caused by PV integration compared to other studies due to already existing infrastructure.
Graphene: The Path to the Future by Graziella Fenech
Graphene, a monolayer of carbon atoms arranged in a hexagonal lattice, evoked a lot of interest in the scientific community since its first appearance back in 2004. Its discovery led Geim and Novoselov to receive the Nobel Prize “for ground breaking experiments regarding the two-dimensional material graphene”. Studying and understanding this nanomaterial unearthed its unique and intriguing properties; including its excellent thermal conductivity and superior mechanical and electrical properties.
Since 2005, efforts for the efficient synthesis of high quality, large area graphene were made. In fact, after the Nobel Prize winning method of mechanical exfoliation was discovered, different synthesis routes were developed, including chemical vapor deposition, and chemical exfoliation. The substrate supporting the graphene has a crucial role in the synthesis and the subsequent fabrication of graphene-based components, primarily due to the fact that graphene has no bulk, meaning that all its atoms are in contact with this said substrate. Currently I am working on introducing slight modifications to the mechanical exfoliation technique, while also studying the effect of the substrate on the deposited flakes. The recent developments in this novel 2D material allow it to play vanguard roles in these constantly evolving times, offering ground-breaking solutions for prevailing problems while also introducing new possibilities.
From Microns to Miles by Dylan Abela
The need for orthopaedic implants is continuously on the rise. According to the American Joint Replacement Registry, in 2015, there was a 102 percent increase in the number of joint arthroplasty procedures, compared to 2014. Austenitic stainless steels are used in this application due to their good corrosion properties and their lower cost when compared to other metallic biomaterials such as titanium and cobalt based alloys. However, more than 90 percent of failures in orthopedic implants made from austenitic stainless steel are due to leaching of metal ions and localised corrosion, together with the effect of tribocorrosion. PVD is used to deposit coatings, to try and inhibit these problems. Previous work has shown that Cr-C coatings possess a combination of high hardness and toughness. Good corrosion resistance was observed, however, transpassive dissolution was recorded at higher potentials. By analysing the microstructure, mechanical properties and corrosion behaviour of heat treated Cr-C coatings, there is a strive to search for improvements in the overall behaviour of the coating to be used in orthopaedic implants. The addition of a coating of a few microns will extend the lifetime of the implant by miles, reducing the need for revision surgery.