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Performance comparison of gallium nitride (GaN) in DC-DC converter circuit
No full textTheoretical thesis.Bibliography: pages 54-59.Chapter 1.Introduction -- Chapter 2. Literature review -- Chapter 3. Analysis and simulation diagram -- Chapter 4. Circuit descriptions and simulations -- Chapter 5. Outcome and results -- Chapter 6. Conclusion.Solar power system is a free sources of sustainable power unlike fossil fuels, and inexhaustible. Converters can shift the level of voltage from one to another through switches. Which is very important for solar power system. Transistor plays a vital role in any converter circuit because the overall efficiency of a circuit depends on the switching losses. Transistor works as switch in a converter circuit. In last few years it has been proven that Gallium Nitride (GaN) based switches have benefits over silicon switches. Using GaN technology reduces the cost of design and the construction of transistors. The GaN based transistor has the ability to operate at a high frequency with low switching power loss. This study is based on a boost converter circuit, where three different transistor model were used to compare their output and efficiency. The output was measured based on simulation conducted on LTSpice platform. Then comes to a decision as to which transistor can give better performance.Mode of access: World wide web1 online resource (59 pages) illustrations (some colour
Engineering biosensors for the detection of unfolded protein response in saccharomyces cerevisiae
No full textTheoretical thesis.Bibliography: pages 41-441. Introduction -- 2. Methods and materials -- 3. Results -- 4. Discussion -- 5. Conclusion and future development.The unfolded protein response (UPR) is activated when the protein folding capacity of the endoplasmic reticulum (ER) is overwhelmed by the accumulation of unfolded proteins inside the ER lumen. In S. cerevisiae, the UPR facilitates the up-and down-regulations of a collection of UPR target genes via the IRE1/HAC1 dependent signalling pathway to bring the ER back to homeostasis. In the application of S. cerevisiae as a cell factory for producing heterologous proteins,low levels of target protein secretion are often associated with the up-regulation of UPR. In this study we constructed nine UPR biosensors using the putative promoter sequences of nine UPR genes including DER1, ERO1, EUG1, HAC1, KAR2, PDI1, PMT2, SEC12 andOST2as sensors, and green fluorescent protein as reporter. We have evaluated these biosensors in their capacities to detect the activation and different levels of UPR, and found that the sensors incorporating the DER1and ERO1 putative promoter sequences gave the best responses across a range of UPR induction levels. This study highlighted the prospect of providing a real-time and high-throughput detection of unfolded protein induced stress and its concomitant influences on protein secretion.1 online resource (47 pages
Structure-function investigation of substrate binding proteins from Synechococcus sp.
No full textTheoretical thesis.Bibliography: pages a-fChapter 1: Molecular understanding of bacterial transport -- Chapter 2: Materials and methods -- Chapter 3: Optimising recombinant production of SBPS -- Chapter 4: Biophysical characterisation of recombinant products -- Chapter 5: ConclusionsSynechococcus is a ubiquitous genus of photosynthetic marine bacteria, and vital for primary production and nutrient cycling in global oceans. Genomic annotation for this genus has progressed faster than the functional characterisation of predicted proteins. Consequently, the veracity of predicted functions for many genes is questionable. This is particularly so for the substrate-binding protein (SBP) family, integral to nutrient import via ATP-binding cassettes, which display unusually low sequence homology (despite a highly conserved structural fold). Lack of validation concerning the natural ligands of SBP proteins impacts on our depth of understanding of the function and utility of cellular import machinery in these highly prevalent marine microorganisms. A panel of nineteen SBPs annotated to bind saccharides across representative Synechococcus species has been selected for in vitro characterisation. Two alternative formats for high-throughput production were trialled, and the yield and percentage of soluble protein products compared. Recombinant forms of three SBPs have been produced in sufficient quantities to enable ligand screening using differential scanning fluorimetry and biophysical characterisation in solution. The approach undertaken has demonstrated potential to complement genomic data for previously uncharacterised SBPs1 online resource (vi, 47, f pages) illustration
Mechanical properties of 3D printed parts and discovering zinc fused deposition modeling
No full textEmpirical thesis.Bibliography: pages 38-39.1. Introduction -- 2. Literature review -- 3. Experimental procedure -- 4. Results-- 5. Discussion -- 6. Conclusion -- 7. Future works -- 8. Appendices -- Bibliography.#D printing is becoming a common method of additive manufacturing complex parts for assembly or final net-shape items. The final 3D printed artefact is to be investigated and compared against traditional methods of manufacturing (injection moulding). To investigate the effects of the 3D printing parameters, layer, size, temperature, print head speed and filament material. This paper will investigate and develop novel direct zinc metal FDM for possible applications such as biomedical and electronics tracing. The novel metal FDM will focus on pure zinc (99.9%), with future developments for zinc magnesium alloys. The purpose of this novel FDM is to produce biocompatible complex shapes for vivo use and for electronics as traces for circuitry.Mode of access: World wide web.1 online resource (xvi, 40 pages illustrations (some colour)
Three D print nozzle
No full textEmpirical thesis.Bibliography: pages 44-45.3D printing -- FDM -- SEM -- CFD -- ANSYS experiment -- Discussion -- Bibliography.3-D printing technology appeared in the mid 90s of the 20th century. In fact, 3D printing is the latest rapid prototyping device, using light curing, stacking technology or other technologies. It uses basically the same principle as ordinary printing. The printer is equipped with liquid or powder or other "print material", through computer control to print material layers together, and finally to make the computer blueprint a reality. This printing technique is called 3D stereoscopic printing technology.At present, laser sintering (SLS) and electronic beam processing (EBM) are commonly used for metal 3D printing technology, but these produces produce enormous energy and significantly increase the temperature during modelling (more than 1000°C), which might be higher than the boiling point of the materials. There is limited metal material that can endure such temperatures; therefore the current metal 3D printing equipment has low cost efficiency and melting the metal is difficult to control. Plastic is still the main material used by most 3D printers. This project will study the use of the FDM process , using low melting point metals, zinc being the choice of testing material. Zinc has high degradability and biocompatibility and can be used in formal prostheses and implants. Finally, a thorough discussion on the deference of the learning time will be provided. This document will report the progress of the project and outline what will be expected in the final report.Mode of access: World wide web.1 online resource ([viii], 45 pages illustrations (some colour)
Smart transportation
No full textEmpirical thesis.Bibliography: pages 29-30.1. Introduction -- 2. Literature review and background -- 3. Strategy and techniques to navigate environment -- 4. LabVIEW architecture -- 5. Conclusion -- Bibliography.The National Instruments Autonomous Robotics Competition is a challenging experience where students are pushed to the limit to create an autonomous vehicle that performs various tasks. We used National Instruments state of the art technology and software, myRIO and LabVIEW. Challenges faced are localisation, path planning and obstacle avoidance, all while trying to complete the tasks at hand.Our design utilises techniques using a mecanum drive system, quadrature encoders and ultrasonic sensors in order to successfully navigate a changing environment accurately. The purpose of my thesis is to be a guide and mentor for future NIARC teams to give them an insight of what to expect and problems they may face. Our research will also serve those looking to find a simple way to successfully navigate a changing environment.Mode of access: World wide web.1 online resource (xiii, 30 pages colour illustrations
Holistic design for a simplistic autonomous vehicle
No full textEmpirical thesis.Bibliography: pages 53-55.1. Introduction -- 2. Background and research -- 3. Design and implementation -- 4. Conclusions -- References.Autonomous vehicle control systems are becoming more and more reliable, efficient and safe than human drivers as time elapses. Thi is a consequence of improved, low power, and high speed embedded processors, advanced high-level development platforms, open source maps and software, high quality, low cost sensors and satellite navigation. This thesis features an investigation of some simplistic control methods used for a miniature vehicle needing to navigate a physical grid with walols in a known, mapped area. The purpose of this thesis is to demonstrate and explain some of the elementary concepts of autonomous control on the most basic level of logic and control. While the vehicle presented is simple, its design would suit many applications, such as factory floor transportation, or a mail delivery system in a building. Consequently, this thesis will be focused on a simplistic, low cost implementations of such a type of system. It will not, however, focus in detail on modern technologies and advanced control systems, such as for example, autonomous road driving. The vehicle developed for this project was designed as an entry in the 2017 NI ARC (National Instruments Autonomous Robotics Competition).Mode of access: World wide web.1 online resource (55 pages colour illustrations
Drag-line sensor for drone assisted meteorite detection
No full textEmpirical thesis.Bibliography: pages 59-61.1. Introduction -- 2.Background and related work -- 3.Project methodology -- 4. Results and discussion -- 5. Conclusions and future work -- Appendix -- Bibliography.Meteorites are great scientific materials in the study of astronomy, planetary geology and astrobiology. They not only provide a glimpse into the wider cosmos, but also stimulate research into the respective fields (stated above), due to their unique material structure and properties. This prompts technological innovations that aid in the detection and identification of these scientific marvels.Current detection methods rely heavily on visual identification or with specialised handheld magnetic sensory equipment. This task is labour intensive and requires large amounts of time to survey suspected landing zones. These zones may have hazardous environments that traverse different land formations and as such prove to be unreachable by researchers and enthusiasts. To alleviate these hardships in the discovery of meteorites, unmanned aerial vehicles (UAV) may be employed. These versatile vehicles are capable of traversing a multitude of environments with a wide range of temperatures and altitudes. Alongside their affordability and functionality, these vehicles are essentially modular, therefore making them transformable to suit any sensory needs, thus reducing equipment costs and labour.The design of magnetic sensory equipment can prove to be invaluable, and the effects of sensor orientation are thoroughly investigated in this document. As such, a key component of this project was based on the effectiveness of a pair of fluxgate magnetometers (Stefan Mayer FLI-500) in a dragline setup and their ability to detect the items of interest, meteorites. Through numerous tests based on susceptibility to both relatively strong magnetic fields (as generated by a bar magnet) and weak magnetic fields (generated from a meteorite's residue magnetic field) and the capabilities of the sensors themselves, the document aims to quantify the sensor's usefulness.In addition to experimental methods, the feasibility of operating the system in conjunction with a micro-controller will provide a plausible system with capabilities ranging from acquisition of sensor data in real time to storage and processing of acquired data to displaying said data either on a display or through wireless communication. However, it is important to note that the preliminary design, prototyping and coding of the sensor suite will have to be refined and completed to allow for actual use in a realistic environment.Mode of access: World wide web.1 online resource (xvii, 61 pages colour illustrations
Web interface for the program analyser Skink
No full textEmpirical thesis.Bibliography: pages 75-76.1. Introduction -- 2. Background literature and related works -- 3. Experimental procedures -- 4. Results -- 5. Discussion -- 6. Conclusions -- 7. Future work -- 8. Abbreviations -- Appendices -- Bibliography.Development of software in this day and age across a wide range of technologies, from embedded closed systems to vital, complex, globally interconnected systems, at some point or another suffer from unforeseen outcomes in the use of these systems. Software bugs and errors are an unfortunate reality in the software development process that are prone to exist due to the difficulty in producing perfect programs. Software verification systems often become incredibly complex, require a large amount of time, resources and knowledge to install and operate. As such it is not always easily accessible to most developers who want to check their work. The goal of this project is to implement an easy to use web interface for an existing C program analysis tool called Skink, that does not require any installation or the use of complex software or software verification knowledge, that will provide software verification feedback to the user.Mode of access: World wide web.1 online resource (xii, 76 pages diagrams, tables
Autonomous wireless controlled robotic arm to pick up and drop tiny object
No full textEmpirical thesis.Bibliography: pages 60-61.Chapter 1. Introduction -- Chapter 2. Background and related work -- Chapter 3. Literature review -- Chapter 4. Proposed work -- Chapter 5. Experiment procedures -- Chapter 6. Results -- Chapter 7. Discussion & conclusion -- 8. Future work -- 9. Abbreviations -- Appendices -- References.The precise movement of a robotic arm is considered challenging, but having to pick up and drop a tiny object wirelessly and autonomously is even harder. The robotic arm will be required to pick up and drop a tiny object autonomously wile also being able to take user input through wireless control. The arm being controlled by a wireless communication system poses a hurdle in terms of data transfer and retention. The main aim of this research is to provide an overview of the methods, specifications and functional requirements of wirelessly controlling a 5 DOF robotic arm. There are certain design challenges that need to be achieved in order for the precise movement of the robotic arm to pick up a tiny object wirelessly. Skills that will be exercised and expanded upon include the use of a 5 DOF robotic arm, control system engineering wireless communication by radio frequency transceivers, MATLAB/Arduino and embedded type coding. Further research and development can be implemented for feedback data from the gripper to further its functionality. The report that follows will outline the experimental methods used and the results obtained through circuit data testing. The main focus of the research is based on the transmission of data and its retention in a control system. As such, further research is needed to design and produce wireless control systems that have a higher degree of accuracy to further improve their functions.Mode of access: World wide web.1 online resource (61 pages colour illustrations