/library/oar/handle/123456789/11954 2025-11-04T22:31:26Z /library/oar/handle/123456789/12970 Title: Video distribution over a campus network using MPEG-DASH Abstract: Internet traffic is growing fast and video data is becoming the dominant traffic that defines the nature of the network. Internet traffic is exposed to delay, stall, congestion and other related problems which lead to the degradation of the quality of video viewing experience. The introduction of the Dynamic Adaptive Streaming over HTTP (DASH) standard from the Moving Picture Expert Group (MPEG) [1] is aimed at addressing these issues. This dissertation studies the distribution of video over a campus network using the MPEG-DASH streaming standard. The study has been carried out using literature review, laboratory experiments and real-world experiments using wired and WiFi media on the University of Malta campus network. Through these experiments it is shown that using the MPEG-DASH streaming standard, video can be played in poor bandwidth network conditions and in fast throughput changing situations with considerable reduction in stall compared to the current existing technology, which is progressive download. Hence improvements in Quality of Experience (QoE) of video is achieved. All the lab experiments and real-world experiment results, provide a picture of the possible improvements, but also problems, when using MPEG-DASH. This helps to strengthen confidence in the deployment of MPEG-DASH and also in its analysis to mitigate its shortcomings, for further improvements in the QoE of the streamed video. Based on the experiments carried out in this dissertation and also based on the related work reported in the literature, it can be concluded that MPEG-DASH increases the QoE when viewing video over a campus network. Description: M.SC.IT 2016-01-01T00:00:00Z /library/oar/handle/123456789/12967 Title: Construction of insertion/deletion error correcting codes using heuristic algorithms Abstract: Insertion deletion channels are very common and found in unexpected places. Various algorithms have been designed to construct good codes to be used in differ- ent scenarios. This work reports research carried out on these different algorithms and their possible use. One of the most recent construction algorithm (Salmon al- gorithm) which shows great potential is compared to an older algorithm (Simulated Annealing algorithm) which is both simple and e ective. The results indicate that the Salmon algorithm is the better algorithm of the two for the scenarios tested. The result were also compared to published upper bounds of various code sizes (from length n = 5 varying to n = 12) and the Salmon Algorithm managed to find better codes. Description: M.SC.IT 2016-01-01T00:00:00Z /library/oar/handle/123456789/12237 Title: Portable device for detecting electric fields in water Abstract: In our electrically powered world, it is not uncommon for electrical alternating current (AC) supply cables or infrastructure to exist in, or close to water. In the event of faults, poor engineering practices or natural disasters, like floods, hazardous, AC voltage leakages can arise, which can be lethal to persons in the water, in close proximity to the fault. This study aims to prevent electrocution by implementing a device which can detect the presence of potentially-lethal water-borne electric fields. The dissertation presents the design and development of a PCB-based prototype, with the aim of preventing electrocution accidents in water. The proposed device is handheld, portable, and battery operated. It consists of discrete electronic components interfaced with a microcontroller, which performs the necessary processing, to detect alternating voltages and determine whether they are lethal in nature. When an AC supply, such as a faulty cable, is exposed to water, it causes water-borne electric fields. Placing two conductors a distance, d apart, perpendicular to the same electric field, a potential difference is observed across the two conductors. This project exploits this phenomenon to detect the presence of AC voltages in water, by detecting AC potential differences across two probes. The detected potential difference is interfaced to the Analogue to Digital Convertor (ADC) input of a microcontroller such that digital signal processing techniques are used to determine the value of the potential difference and display it on a bar-graph display. This study is mainly concerned with the design and implementation of the interface circuit, built using discrete components and the routines to be executed by the microcontroller. The selection of the best microcontroller and programming language to use is also discussed, leading to the selection of the ATMEGA328PB AVR microcontroller and the C programming language. This dissertation reports on 62 test cases, which show that the proposed device is capable of detecting AC voltages with an average accuracy of 99.13% of the actual voltage. This high level of accuracy confirms that the proposed device meets the functional requirement, is capable of detecting leaking alternating voltages in water, and can potentially save lives. Description: B.SC.IT(HONS) 2016-01-01T00:00:00Z /library/oar/handle/123456789/12189 Title: Internet of things in 4G and beyond Abstract: This project consists of two main parts. The first part of this project is a literature review that focuses on papers and publications that discuss the concept of cellular data such as 4G and 5G in the Internet of Things (IoT). Proposals made by prominent authors in the field will be presented and evaluated. An additional section of this first part deals with background information on this subject in order to familiarise the reader with the basic knowledge about this subject. In the second part an IoT prototype is designed with the aim of being installed in a home environment. This prototype runs, but not exclusively, on 4G or, in the near future, 5G. The prototype built was functionally tested and where possible improved. The prototype is implemented twice with different setups. In the first setup an Arduino is used as a controlling/monitoring platform, controlled from a webpage. The webpage is hosted on a PC running the WinLAMP version 2 application and connected to the Arduino via the WiFi router. The setup does not require an Internet connection and it can be controlled by any Wi- Fi device connected to the same WiFi router. However, if the WiFi router is connected to the Internet, the IoT platform can be controlled by using a 4G, or any other, device connected to the Internet. This makes it possible for the user to control and monitor the devices from home or away from it. In the second setup the Arduino IoT prototype device platform is connected to a 4G WiFi Router to connect it to the Internet, instead of using a traditional Ethernetconnected modem. This is used in cases where there is an unstable or even no Ethernet connection. The tests were made according to the specifications of the prototype. The purpose of the testing was to find its limits and efficiency and in order to provide insights and knowledge in this field of study that could inform any future work. Description: B.SC.IT(HONS) 2016-01-01T00:00:00Z