English language institute in Greece: A business proposal

The aim of this project is to propose a model for a private English language school in Greece with an emphasis on English for business purposes

A Framework for File Format Fuzzing with Genetic Algorithms

Secure software, meaning software free from vulnerabilities, is desirable in today\u27s marketplace. Consumers are beginning to value a product\u27s security posture as well as its functionality. Software development companies are recognizing this trend, and they are factoring security into their entire software development lifecycle. Secure development practices like threat modeling, static analysis, safe programming libraries, run-time protections, and software verification are being mandated during product development. Mandating these practices improves a product\u27s security posture before customer delivery, and these practices increase the difficulty of discovering and exploiting vulnerabilities. Since the 1980\u27s, security researchers have uncovered software defects by fuzz testing an application. In fuzz testing\u27s infancy, randomly generated data could discover multiple defects quickly. However, as software matures and software development companies integrate secure development practices into their development life cycles, fuzzers must apply more sophisticated techniques in order to retain their ability to uncover defects. Fuzz testing must evolve, and fuzz testing practitioners must devise new algorithms to exercise an application in unexpected ways. This dissertation\u27s objective is to create a proof-of-concept genetic algorithm fuzz testing framework to exercise an application\u27s file format parsing routines. The framework includes multiple genetic algorithm variations, provides a configuration scheme, and correlates data gathered from static and dynamic analysis to guide negative test case evolution. Experiments conducted for this dissertation illustrate the effectiveness of a genetic algorithm fuzzer in comparison to standard fuzz testing tools. The experiments showcase a genetic algorithm fuzzer\u27s ability to discover multiple unique defects within a limited number of negative test cases. These experiments also highlight an application\u27s increased execution time when fuzzing with a genetic algorithm. To combat increased execution time, a distributed architecture is implemented and additional experiments demonstrate a decrease in execution time comparable to standard fuzz testing tools. A final set of experiments provide guidance on fitness function selection with a CHC genetic algorithm fuzzer with different population size configurations

Embedded Firmware Solutions

Computer scienc

2017 Annual Research Symposium Abstract Book

2017 annual volume of abstracts for science research projects conducted by students at Trinity College

Dielectric Waveguides for Electromagnetic Band Gap (EBG) Structures, Antennas, and Microwave Circuits

Dielectric waveguide structures, formed using rectangular blocks of dielectric, can guide electromagnetic energy in a frequency range suitable for new microwave antennas and devices, or between 2 GHz and 18 GHz. In this thesis, we present the analysis and design of thin dielectric waveguide structures so small that for the first time, they can be made economically out of readily available substrates, or circuit boards, even at these frequencies. These strikingly thin metallic-bound dielectric waveguides (H-guides), to be operated in a single fundamental mode, are analyzed and subsequently applied to three brand new applications: a square periodic H-guide structure, an antenna, and a thin H-guide dual-directional coupler. In the first application, we investigate periodic dielectric structures, or Electromagnetic Band Gap (EBG) structures, where a new model for periodicity applies thin H-guide transmission lines with discontinuities. This model allows for the resonant frequency, transmission (S21), and reflection (S11) parameters of such structures to be found quickly and quite accurately with closed form expressions, without the need for any numerical methods. As an added benefit of the new model, which can be represented as a z-transform, an inverse operation exists, creating the possibility to design a structure that meets a certain frequency response. In the second application, we explore the use of the thin H-guide as a transmission line feed for a new type of aperture horn antenna that is not only high gain, but also wideband. Incredibly, with proper design, the antenna can also meet low-sidelobe levels between frequencies of 8 and 18 GHz. The proposed thin H-guide aperture horn antennas have wider bandwidths than typical array designs, have similarly high gains as compared to traditional air-filled horn antennas, and can even be easily fabricated using typical two dimensional substrate machining processes. The prototype operates from 8 to 18 GHz with a peak gain of about 18 dBi with reference to the H-guide transmission line. To make antenna fabrication and measurement of periodic dielectric structures possible, a new transition based on microstrip design has been carefully developed that exceeds the performance of all previous microstrip to dielectric waveguide transition designs. This wideband, low loss, Bézier-shaped microstrip to thin H-guide transition has been carefully developed and is discussed in detail in this thesis. This transition can even be fabricated using the same two dimensional substrate machining processes used for the H-guide aperture horn antenna, which allows for the seamless integration of the two structures. Finally, a dual-directional H-guide coupler is discussed that is much thinner than air-filled waveguide designs. The structure is so thin that its total thickness can be less than 2 millimeters, where the design obtains a directivity of better than 25 dB over a large bandwidth of 8 to 14 GHz

Distributed situation awareness: Advances in theory, measurement and application to team work

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Situation Awareness (SA) is critical commodity for teams working in complex sociotechnical systems and is thus a fundamental consideration in collaborative system design and evaluation. Despite this, SA remains predominantly an individual construct, with the majority of models and measures focused on SA from an individual perspective. In comparison, team SA has received much less attention and this thesis argues that further work is required in the area both in relation to the development of theoretical perspectives and of valid measures, and to the development of guidelines for system, training and procedure design. This thesis advances team SA theory and measurement by further investigating a recently proposed model of SA in complex collaborative environments, the Distributed Situation Awareness (DSA) approach, and by testing a new methodology for representing and analysing DSA during real world collaborative activities. A review of SA theory and SA measurement approaches is presented. Following this, the DSA theory and propositional network assessment methodology are outlined and a series of case studies on DSA during real world collaborative activities in the military and civil domains are presented. The findings are subsequently used to explore the concept of DSA and the sub-concepts of compatible and transactive SA. In conclusion, a model of DSA in complex collaborative systems is presented, and a series of system design guidelines for supporting DSA are outlined

An experimental study of low-temperature combustion in a diesel engine

Increased efficiency and reduced emissions demands from users and legislative organisations have lead to the development of advanced combustion technologies for diesel engines. Exhaust gas recirculation (EGR) is a widely used technology to control diesel combustion and emissions, primarily to reduce emissions of oxides of nitrogen (NOx). Implementation of high levels of EGR (> 50%) is able to simultaneously reduce both emissions of NOx and particulate matter (PM) to ultra low levels. However, high EGR combustion is subject to reduced combustion efficiency and stability with increased total hydrocarbon (THC) and carbon monoxide (CO) emissions. This thesis presents research into low temperature diesel combustion (LTC) operation and the effects on combustion and emissions when the engine is operated under air, fuel and EGR rates encountered during transitions between LTC and conventional diesel operation modes. This has resulted in an improved understanding of the diesel combustion process and pollutant emissions with high rates of EGR, different fuel injection pressures and timings, post fuel injection and exhaust back pressures. The sensitivity of LTC to variations in engine speed, fuel injection quantity, and EGR rate and intake manifold temperature were investigated. Pseudo-transient operation of the engine was studied to interpret the transient performance of a diesel engine during transients within LTC and from LTC to conventional diesel combustion in a new European driving-cycle (NEDC) test. Experimental investigations were conducted on a single cylinder research diesel engine. Cylinder pressure, fuel consumption and gaseous and particulate emissions (filter smoke number, size distribution, and total number) were measured. The results showed that an increase in EGR rate can realise LTC on the research engine. Fuel injection parameters influenced the combustion phasing, and control of this was able to improve the combustion stability and to reduce the THC and CO emissions. The low smoke number for the LTC diesel combustion was a result of reduced mean particle size with possible changes in particulate composition. EGR is the most critical parameter influencing the LTC combustion and emissions. Transient simulation of an engine exhibits significant discrepancies in EGR rate and boost pressure. Pseudo-transient points at intermediate load condition showed significantly increased emissions, particularly smoke number. Retarded fuel injection timing and increased boost pressure were demonstrated to be an effective strategy to reduce smoke emissions for these pseudo-transient operating points