Data security for third generation telecommunication systems

This research work started as a humble, and yet ambitious attempt of enhancing the current security level in wireless data communication. Detailed analysis of the existing security protocols and wireless networks, together with their strengths and weaknesses, presented in the beginning of this thesis, indicates the need of employing human voice as an alternative security solution. Consequently the presentation of the state of the art biometric solutions and their applicability to the desired communication medium is more than necessary. However, the lack of previous involvement of human voice in an encryption method with successful results, constitute the core of this work. The majority of biometric applications aim to improve the confidence of the system to know whether a user is who he or she claims to be (authentication) and a few of them help the system in deciding his/her identity (identification). This novel method of encryption combines wireless communication (especially Third Generation mobile phones), data security, digital signal processing and smart cards. All these four different research areas have been covered theoretically in the beginning of this thesis. Thorough discussion of the fundamental principles governing each area results in identifying the strengths and weaknesses of these four core research elements and benefits the implementation stages of this work. Continuing with the thesis and proceeding to the second part, the theoretical analysis has been backed up by experimental development and testing. Every aspect of the novel research architecture has been transformed into a research algorithm. The performance of the algorithm, its cohesion and coupling has been closely investigated. The overall result of the research work accompanied with the algorithm’s strengths and weaknesses, future directions together with possible applicability of the research solution provide the epilogue of this scientific journey has been discussed

Feature-domain super-resolution framework for Gabor-based face and iris recognition

The low resolution of images has been one of the major limitations in recognising humans from a distance using their biometric traits, such as face and iris. Superresolution has been employed to improve the resolution and the recognition performance simultaneously, however the majority of techniques employed operate in the pixel domain, such that the biometric feature vectors are extracted from a super-resolved input image. Feature-domain superresolution has been proposed for face and iris, and is shown to further improve recognition performance by capitalising on direct super-resolving the features which are used for recognition. However, current feature-domain superresolution approaches are limited to simple linear features such as Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA), which are not the most discriminant features for biometrics. Gabor-based features have been shown to be one of the most discriminant features for biometrics including face and iris. This paper proposes a framework to conduct super-resolution in the non-linear Gabor feature domain to further improve the recognition performance of biometric systems. Experiments have confirmed the validity of the proposed approach, demonstrating superior performance to existing linear approaches for both face and iris biometrics

Improved Zn-based coatings for ipersandelin steel products

The protection of iron-based alloy products against corrosion is fundamental to preserve their mechanical properties in aggressive environments. Hot-dip galvanizing process represents one of the most used techniques to make protective coatings for such products. In order to improve both mechanical and chemical properties of coating, metallic elements may be added to the traditional zinc bath. In the present paper, two types of improved zinc-based coating are proposed: (i) A coating obtained employing a tin addition (3% in weight); (ii) A coating obtained employing aluminium (5% in weight), tin (1% in weight) and copper (0.5% in weight) additions. Firstly, the performance of such two types of coatings is experimentally investigated through bending tests on ipersandelin steel plate specimens, treated through different bath dipping times. The intermetallic phase thicknesses of coatings are measured for each dipping time, in order to evaluate the kinetic formation. Then, a Finite Element (FE) model is proposed in order to simulate the bending behaviour of the above specimens, both employing the measured phase thickness and implementing the loading and boundary conditions of the experimental tests. A numerical non-linear static analysis is performed. A quite satisfactory agreement between experimental and numerical results is observed, especially under plastic behaviour regime

New VISTAs in Science Education

In the summer of 2012, a colleague and I attended the four-week Virginia Initiative for Science Teaching and Achievement (VISTA) Elementary Summer Science Institute where we were trained to conduct inquiry-based science teaching in a problem-based learning setting. We then implemented our training in our own academic classrooms by developing a Problem-Based Learning unit meeting the objectives of our Virginia standards-based science curriculum and selecting a topic with tics to our local community. Toward demonstrating that students, teachers, and educational systems stand to benefit from the implementation of this methodology, this article clarifies the following aspects: 1) outlines the problem, scenario, and process of developing a Problem-Based Leaming unit; 2) explains the delivery in the classroom; 3) analyzes ongoing formative and summative assessments; 4) and, discusses the influence on students, teachers, and instruction as a whole

Assessment of sensor performance

There is an international commitment to develop a comprehensive, coordinated and sustained ocean observation system. However, a foundation for any observing, monitoring or research effort is effective and reliable in situ sensor technologies that accurately measure key environmental parameters. Ultimately, the data used for modelling efforts, management decisions and rapid responses to ocean hazards are only as good as the instruments that collect them. There is also a compelling need to develop and incorporate new or novel technologies to improve all aspects of existing observing systems and meet various emerging challenges. Assessment of Sensor Performance was a cross-cutting issues session at the international OceanSensors08 workshop in Warnemünde, Germany, which also has penetrated some of the papers published as a result of the workshop (Denuault, 2009; Kröger et al., 2009; Zielinski et al., 2009). The discussions were focused on how best to classify and validate the instruments required for effective and reliable ocean observations and research. The following is a summary of the discussions and conclusions drawn from this workshop, which specifically addresses the characterisation of sensor systems, technology readiness levels, verification of sensor performance and quality management of sensor systems