/library/oar/handle/123456789/65866 2026-06-22T08:48:34Z /library/oar/handle/123456789/121343 Title: Analysis of EOG data recorded while reading Abstract: Reading is the activity through which humans decipher written symbols in an effort to extract information from written text. It is a medium through which knowledge is shared and communication is exercised. Whether written on paper, or displayed on an electronic screen, literacy can be considered as a valuable tool to one’s social and educational development. While reading, humans perform a wide variety of different eye movements intended to maximize the rate with which information is collected. Through the use of electrooculography (EOG) data, the ocular movements performed by humans while reading can be recorded, analysed and classified. These eye movements harness valuable information regarding the user’s reading capabilities, proficiency in a language and familiarity with a particular topic. By monitoring and carefully analysing these ocular movements, reading disorders such as dyslexia can be identified and inferences regarding the layout of the text at hand can be made. This project, has made use of EOG data recorded while reading in order to investigate the manifestation of different eye movements performed while reading. Through this, a Wordometer application was developed, capable of measuring the quantity of reading. Through the incorporation of various classification measures, this application provided various reading statistics, such as word estimates, reading speeds, lines read and quantifying various eye movements. Providing the reader with this information, can in turn motivate the user to improve his/her reading speeds as well as increase his/her reading volumes. Secondly, EOG based eye gaze tracking was explored in order to track the progression of the user while reading paragraphs of text. The latter is ultimately intended to permit the execution of commonly used commands, such as the selection of hyperlinks on a website, through eye movements rather than using conventional input devices such as keyboards and touchscreens. This would also facilitate the experience for users with mobile impairments as commonly used tools can be accessed using simple ocular movements as a control input. Description: B.ENG.(HONS) 2020-01-01T00:00:00Z /library/oar/handle/123456789/120491 Title: Real time monitoring for the efficient use of industrial pneumatic applications Abstract: Manufacturing companies are becoming increasingly aware of the financial and environmental penalties linked with inefficient compressed air systems. Traditional methodologies of identifying and maintaining compressed air inefficiencies have proved to be ineffective. Therefore, current market trends are shifting towards implementing smart monitoring devices that make use of Industry 4.0 to communicate information in real time. A significant portion of analysed case studies and market options implemented monitoring devices that analysed data from the supply side of the system. According to the literature, demand side inefficiencies account for 50-70% of the total compressed air improvement opportunities. However, only one market option was identified which monitored the demand parameters and it made use of highly proprietary equipment that drove up implementation costs. Therefore, a real time demand side data monitoring system was designed to scientifically answer the research questions that were established. The experimental procedures showed that three different parameters had to be monitored in order to identify inefficiencies at the demand side. These included system pressure, system flow rate and actuation rate. The latter parameter was an innovative way of analysing different inefficiencies through the digital time stamps of solid state switches installed with each compressed air actuator. Through these digital data time stamps, the actuation rate was monitored in a highly accurate manner by using a technique that was not encountered in the literature survey. The results showed that with an introduction of a large 1.61mm leak, the actuation rate of an actuator decreased marginally by 0.82% while the actuation rate of a faster secondary cylinder decreased by 1.57%. This concluded that a leak within an automation system impacted the actuation rate of all actuators within that system. The change in actuation rate was interpreted through Bernoulli’s principles which was related to a decrease in static pressure that was caused by an increase in flow rate due to a 1.61mm leak. Moreover, by correlating the changes that were measured in terms of system pressure, compressed air flow rate and actuation rate, inefficiencies such as leakages, faulty actuators and an increase in system pressure were identified at the demand side with the use of standard equipment and sensors. Description: M.Sc.(Melit.) 2020-01-01T00:00:00Z /library/oar/handle/123456789/120484 Title: Biodegradable iron-based scaffolds : developing a replication method using additive manufacturing Abstract: Orthopaedic trauma patients may require a load bearing scaffold to assist their recovery. Ideally such a scaffold would be biodegradable, with its degradation rate matching that of bone growth and with pore diameter in the range of 100 µm to 800 µm. Research being carried out on iron-based scaffolds suggests that this can be achieved. This work is aimed to develop a reliable fabrication process for biodegradable iron scaffolds, based on the replication method combined with stereolithography (SLA) 3D printing. The replication method is a powder metallurgy technique which uses a perishable polymer template that is coated with a slurry containing the desired iron-based final material. Instead of using said slurry, a dry coating technique was developed which made use of the inherent tackiness of the 3D printed polymer templates, to attach the powder. The metallic coated polymer template is then heat treated at a low temperature to partially sinter the powder coating to form an interconnected lattice. This is then followed by a high temperature heat treatment to completely burn away the polymer template and fully sinter the metallic scaffold implant. In this work, the technique was developed further by incorporating SLA 3D printing to produce the polymeric templates thus making it possible to produce patient specific scaffolds at a very low price. Two template types were developed namely, cubic and gyroid type templates. To develop this adapted replication method, the SLA 3D printing polymer was analysed using dynamic mechanical analysis, differential scanning calorimetry and furnace heat treatments, to determine the softening and degradation temperatures. The 3D printed templates were analysed using optical microscopy and scanning electron microscopy to analyse their strut and pore size. Coated templates were subsequently analysed using weighted coating mass uptake and X-ray Microscopy. Scanning electron microscopy with electron dispersive spectroscopy was employed to characterise the powder used and the final heat-treated iron lattices. For both template types, the minimum achievable pore and strut size was 600 µm and 420 µm respectively. The optimal pore and strut size was set to 1000 µm and 700 µm, to minimise pore clogging for gyroid templates and to cater for the shrinkage experienced during heat treatment. The best heat treatment achieved used milled iron powder (particle diameter about 1.5 µm), coated using the dry coating method and heat treated with the first dwell at 175°C for 2 hours and a final dwell at 1120°C for 3 hours. Description: B.Eng. (Hons)(Melit.) 2020-01-01T00:00:00Z /library/oar/handle/123456789/98739 Title: Incylinder heat transfer and friction analysis in pressurised motored compression ignition engine Abstract: An experimental study was performed to investigate the total mechanical friction and in-cylinder heat transfer from a pressurised motored engine. The mechanical friction study was done on a four-cylinder engine, whereas heat transfer experiments were conducted on a single cylinder version of the same engine model as the four cylinder, converted in the same project. The pressurised motored setup was modified from its conventional configuration to allow the engine to be run on gases other than air. Argon and its mixtures with air were used as the working gas. This method made it possible to test the motored engine at peak bulk gas temperatures up to 1200, around 600 higher than what is expected from conventional motoring using air. An investigation of several engine metrics in relation to the working gas was carried out. It was found that the location of peak in-cylinder pressure and location of peak bulk gas temperature are advanced from TDC by a magnitude that is directly proportional to the peak bulk gas temperature. The summation of the losses of heat and blow-by were found to show a linear increase with an increase in the peak bulk gas temperature, whereas the losses associated with the pumping of the gas showed a decrease with using gases of higher ratios of specific heats. The mechanical friction of the pressurised motored engine was found to be insensitive to the bulk gas temperature, and its effect on the combustion chamber surface temperature. It was hypothesised that this result is probably due to the gas pressure phasing with crank angle of the pressurised motored engine, which exhibits the peak gas pressure load very close to TDC where the piston lateral thrust is small. With the devised setup, the thermal load on the motored engine could be studied independently from the gas pressure load, however phasing of gas pressure with crank angle could not be changed. For the study of the transient component of heat flux from the combustion chamber, two fast response thermocouples of the eroding type were installed; one at the valve bridge, and another at the cylinder periphery in the squish region. The methods used for converting the temporal surface temperature measurements to heat flux were the traditional Fourier method and the Impulse Response method. The Impulse Response method was applied using basis functions obtained from a two-dimensional finite element study of the eroding thermocouple. This analysis allowed an evaluation of the heat flow that occurs in three different types of eroding thermocouples based on Zirconia, Stainless Steel and Aluminium. It was found that significant two-dimensional effects occur at the surface of the Aluminium and Zirconia based thermocouples, whereas only minute two-dimensional heat transfer was noted for the Stainless-Steel based thermocouple. A parametric in-cylinder heat flux study was conducted, where it was found that the transient component of heat flux increases with an increase in engine speed and peak in-cylinder pressure. An increase in the transient component of heat flux was also noted with using gases of higher ratios of specific heats; however, it was found that the increase in heat flux experienced with the range of gases tested was not as large as initially expected. Results from this experimental session were compared to existing zero-dimensional and one-dimensional heat flux models. It was found that zero-dimensional, one-zone models of the Annand and Woschni type are able to determine the cycle-averaged total heat flux, but unable to predict the temporal heat flux curve. On the other hand, one-dimensional heat flux models derived from the one-dimensional unsteady energy equation in the boundary layer showed very good correlation with the experimental heat flux in terms of the temporal variation, but underpredicted the magnitude. Description: PH.D 2020-01-01T00:00:00Z