Signal modelling: A versatile approach for the automatic analysis of the electroencephalogram

Despite recent advances in brain monitoring techniques, the electroencephalogram (EEG) is still widely used in the diagnosis and monitoring of epilepsy. To increase its effectiveness, long-term monitoring of patients was proposed but the large volume of recorded EEG signals produced, made their traditional interpretation by human experts difficult and automatic EEG analysis was proposed as an alternative. This Thesis is concerned, primarily, with the on-line detection of epileptic transients (spikes) in the interictal EEG signals of patients. A review of previous methods, revealed that the limited success of automatic analysis systems was linked to the vagueness of neurophysiological definitions and the subjectiveness of human interpretation, which is based on experience. To address these issues, it was realized that a common point of reference is required for the integration of medical and signal processing expertise, which could be provided by a model of the signal. Early attempts to develop such a model are described. These led to the development of spike detectors based on the derivatives of the EEG. Later, by describing medical definitions with signal processing terminology, a comprehensive model of the signal was constructed. This was based on its decomposition into background activity, spikes, transients and noise and describing each one of them in terms of simple, random signals and quasi-linear systems. This suggested a method of analysis based on inverse modelling for the decomposition of the EEG. The model for transients was estimated off-line. An on-line system, consisting of adaptive prediction error systems, constrained all-pole adaptive systems and a basic signal detection procedure was implemented. Several alternative adaptive realizations were investigated. The spike detection procedure was generalized for the detection of other transients. Finally this procedure was replaced by a Multi-Layer Perceptron neural network, whose inherent ability to learn by example is important, as it provides the means to incorporate medical experience without requiring its explicit quantification. The system is flexible and its extension to detect any number of transients is demonstrated. The method may be applied to other signals and improved by new developments in signal processing

An Economic Study of the Effect of Android Platform Fragmentation on Security Updates

Vendors in the Android ecosystem typically customize their devices by modifying Android Open Source Project (AOSP) code, adding in-house developed proprietary software, and pre-installing third-party applications. However, research has documented how various security problems are associated with this customization process. We develop a model of the Android ecosystem utilizing the concepts of game theory and product differentiation to capture the competition involving two vendors customizing the AOSP platform. We show how the vendors are incentivized to differentiate their products from AOSP and from each other, and how prices are shaped through this differentiation process. We also consider two types of consumers: security-conscious consumers who understand and care about security, and na\"ive consumers who lack the ability to correctly evaluate security properties of vendor-supplied Android products or simply ignore security. It is evident that vendors shirk on security investments in the latter case. Regulators such as the U.S. Federal Trade Commission have sanctioned Android vendors for underinvestment in security, but the exact effects of these sanctions are difficult to disentangle with empirical data. Here, we model the impact of a regulator-imposed fine that incentivizes vendors to match a minimum security standard. Interestingly, we show how product prices will decrease for the same cost of customization in the presence of a fine, or a higher level of regulator-imposed minimum security.Comment: 22nd International Conference on Financial Cryptography and Data Security (FC 2018

Local E-Government in Cyprus: A Comparison of Perceptions Between Citizens and Decision Makers

This paper identifies attitudes and perceptions on e-government among two key populations: citizens of the Republic of Cyprus and local government decision makers. The research methodology is based on both secondary and primary data collection, with the latter including a questionnaire survey of the public and another of major local governments\u27 officials who were directly involved in the decision making of the services provided through local egovernment initiatives. The results of the surveys are analysed and cross-related The research has reached three principal clusters of conclusions. The first relates to a number of discrepancies found when comparing the public\u27s perceptions, needs and potentialities on e-government and the corresponding perceptions of the municipality decision makers. The second cluster relates to the wider potentialities of local e-government in Cyprus. The third cluster is provides directions and towards a successful local e-government implementation in Cyprus

The application of useless Japanese inventions for requirements elicitation in information security

Rules of requirements elicitation in security are broken through the use of Chindōgu, by designing impractical security countermeasures in the first instance, then using these to create usable security requirements. We present a process to conceive the requirements in Chindōgu form. We evaluate the usefulness of this process by applying it in three workshops with data gathered from a European rail company, and comparing requirements elicited by this process with a set of control requirements

Collaborative Gaze Channelling for Improved Cooperation During Robotic Assisted Surgery

The use of multiple robots for performing complex tasks is becoming a common practice for many robot applications. When different operators are involved, effective cooperation with anticipated manoeuvres is important for seamless, synergistic control of all the end-effectors. In this paper, the concept of Collaborative Gaze Channelling (CGC) is presented for improved control of surgical robots for a shared task. Through eye tracking, the fixations of each operator are monitored and presented in a shared surgical workspace. CGC permits remote or physically separated collaborators to share their intention by visualising the eye gaze of their counterparts, and thus recovers, to a certain extent, the information of mutual intent that we rely upon in a vis-à-vis working setting. In this study, the efficiency of surgical manipulation with and without CGC for controlling a pair of bimanual surgical robots is evaluated by analysing the level of coordination of two independent operators. Fitts' law is used to compare the quality of movement with or without CGC. A total of 40 subjects have been recruited for this study and the results show that the proposed CGC framework exhibits significant improvement (p<0.05) on all the motion indices used for quality assessment. This study demonstrates that visual guidance is an implicit yet effective way of communication during collaborative tasks for robotic surgery. Detailed experimental validation results demonstrate the potential clinical value of the proposed CGC framework. © 2012 Biomedical Engineering Society.link_to_subscribed_fulltex

Use-Case Informed Task Analysis for Secure and Usable Design Solutions in Rail

Meeting secure and usable design goals needs the combined effort of safety, security and human factors experts. Human factors experts rely on a combination of cognitive and hierarchical task analysis techniques to support their work. We present an approach where use-case specifications are used to support task analysis, and human failure levels help identify design challenges leading to errors or mistakes. We illustrate this approach by prototyping the role of the European Railway Traffic Management System (ERTMS) - Signaller, which provides human factors experts a chance to work in collaboration with safety and security design experts

Quantization of Magnetic Poisson Structures:LMS/EPSRC Durham Symposium on Higher Structures in M-Theory

We describe three perspectives on higher quantization, using the example of magnetic Poisson structures which embody recent discussions of nonassociativity in quantum mechanics with magnetic monopoles and string theory with non-geometric fluxes. We survey approaches based on deformation quantization of twisted Poisson structures, symplectic realization of almost symplectic structures, and geometric quantization using 2-Hilbert spaces of sections of suitable bundle gerbes. We compare and contrast these perspectives, describing their advantages and shortcomings in each case, and mention many open avenues for investigation.Comment: 13 pages, Contribution to Proceedings of LMS/EPSRC Durham Symposium Higher Structures in M-Theory, August 201

Alternative activation of macrophages by filarial nematodes is MyD88-independent

AbstractAlternative macrophage activation is largely defined by IL-4Rα stimulation but the contribution of Toll-like receptor (TLR) signaling to this phenotype is not currently known. We have investigated macrophage activation status under Th2 conditions in the absence of the core TLR adaptor molecule, MyD88. No impairment was observed in the ability of MyD88-deficient bone marrow derived macrophages to produce or express alternative activation markers, including arginase, RELM-α or Ym1, in response to IL-4 treatment in vitro. Further, we observed no difference in the ability of peritoneal exudate cells from nematode implanted wild type (WT) or MyD88-deficient mice to produce arginase or express the alternative activation markers RELM-α or Ym1. Therefore, MyD88 is not a fundamental requirement for Th2-driven macrophage alternative activation, either in vitro or in vivo