An ecological approach to anomaly detection: the EIA Model.

The presented work proposes a new approach for anomaly detection. This approach is based on changes in a population of evolving agents under stress. If conditions are appropriate, changes in the population (modeled by the bioindicators) are representative of the alterations to the environment. This approach, based on an ecological view, improves functionally traditional approaches to the detection of anomalies. To verify this assertion, experiments based on Network Intrussion Detection Systems are presented. The results are compared with the behaviour of other bioinspired approaches and machine learning techniques

Comprehensive Aspectual UML Approach to Support AspectJ

Unified Modeling Language is the most popular and widely used Object-Oriented modelling language in the IT industry. This study focuses on investigating the ability to expand UML to some extent to model crosscutting concerns (Aspects) to support AspectJ. Through a comprehensive literature review, we identify and extensively examine all the available Aspect-Oriented UML modelling approaches and find that the existing Aspect-Oriented Design Modelling approaches using UML cannot be considered to provide a framework for a comprehensive Aspectual UML modelling approach and also that there is a lack of adequate Aspect-Oriented tool support. This study also proposes a set of Aspectual UML semantic rules and attempts to generate AspectJ pseudocode from UML diagrams. The proposed Aspectual UML modelling approach is formally evaluated using a focus group to test six hypotheses regarding performance; a “good design” criteria-based evaluation to assess the quality of the design; and an AspectJ-based evaluation as a reference measurement-based evaluation. The results of the focus group evaluation confirm all the hypotheses put forward regarding the proposed approach. The proposed approach provides a comprehensive set of Aspectual UML structural and behavioral diagrams, which are designed and implemented based on a comprehensive and detailed set of AspectJ programming constructs

Ontology-Based Multiple Choice Question Generation

With recent advancements in Semantic Web technologies, a new trend in MCQ item generation has emerged through the use of ontologies. Ontologies are knowledge representation structures that formally describe entities in a domain and their relationships, thus enabling automated inference and reasoning. Ontology-based MCQ item generation is still in its infancy, but substantial research efforts are being made in the field. However, the applicability of these models for use in an educational setting has not been thoroughly evaluated. In this paper, we present an experimental evaluation of an ontology-based MCQ item generation system known as OntoQue. The evaluation was conducted using two different domain ontologies. The findings of this study show that ontology-based MCQ generation systems produce satisfactory MCQ items to a certain extent. However, the evaluation also revealed a number of shortcomings with current ontology-based MCQ item generation systems with regard to the educational significance of an automatically constructed MCQ item, the knowledge level it addresses, and its language structure. Furthermore, for the task to be successful in producing high-quality MCQ items for learning assessments, this study suggests a novel, holistic view that incorporates learning content, learning objectives, lexical knowledge, and scenarios into a single cohesive framework

Some Considerations on Dependability Issues and Cyber-Security of Cyber-Physical Systems

International audienceFor the last recent years, there has been a convergence between computer engineering approaches and automation aspects (industrial systems, internet of things) also called cyber-physical systems, for the development of process-based cyber-security strategies. Classically, security studies are based on risk analysis. Compared to classical IT approaches, the actual process (for instance a nuclear power plant or a chemical process) or system (autonomous car, drone) are taken into account in our approach for two reasons. The first reason is that the vulnerabilities of such systems or processes vary dynamically as a function of the time, the second reason is because the "standards" context is depending on the application domain and relationships with the IEC 61508 functional safety standard seems relevant. The paper presents a state of the art of problematics and proposed some approaches to these issues

Analysis Of Phishing Susceptibility In A Workplace: A Big-Five Personality Perspectives

Employee is frequently referred to as the weakest link in the cyber security in an organization. Differences in the employees’ personality makes it hard for any organization to design a proper mitigation strategy in order to prevent them from being a victim of phishing attack. Besides, users’ general life experience and technological experience will also influence the type of user’s personality traits while handling or interacting with the security system, which affects their susceptibility towards phishing. The objective of this paper is to examine the personality traits that influence phishing susceptibility among employees in a workplace, and to investigate the influence of employees’ experience in shaping employees’ personality and consequently their behaviour in resisting phishing attack. This study used quantitative method. A survey (N = 252) of employees in mid-sized IT related companies in Malaysia attempted to identify individual’s characteristics that relate to phishing susceptibility and characterize the higherrisk employees that pose threats to the companies. This paper presents three notable findings. First, the results of correlation analysis emphasized the importance of employees’ technical and general experience in shaping their personality to resist phishing attack. Secondly, the results of correlation analysis show that conscientiousness and self-monitoring personality traits were positively related with employee’s secure behaviour towards phishing threats. Finally, this study concluded that extroversion personality had the strongest influence towards phishing susceptibility, followed by self-monitoring, agreeableness and conscientiousness. The findings suggest that there is an inverse influence between personality traits (independent variables) and user behaviour (dependent variable). The proposed framework is useful for research attempting to shift concern on human factors in order to help organization improving employees’ cyber security complianc

CONTRIBUTIONS TO EFFICIENT AUTOMATIC TRANSCRIPTION OF VIDEO LECTURES

Tesis por compendio[ES] Durante los últimos años, los repositorios multimedia en línea se han convertido en fuentes clave de conocimiento gracias al auge de Internet, especialmente en el área de la educación. Instituciones educativas de todo el mundo han dedicado muchos recursos en la búsqueda de nuevos métodos de enseñanza, tanto para mejorar la asimilación de nuevos conocimientos, como para poder llegar a una audiencia más amplia. Como resultado, hoy en día disponemos de diferentes repositorios con clases grabadas que siven como herramientas complementarias en la enseñanza, o incluso pueden asentar una nueva base en la enseñanza a distancia. Sin embargo, deben cumplir con una serie de requisitos para que la experiencia sea totalmente satisfactoria y es aquí donde la transcripción de los materiales juega un papel fundamental. La transcripción posibilita una búsqueda precisa de los materiales en los que el alumno está interesado, se abre la puerta a la traducción automática, a funciones de recomendación, a la generación de resumenes de las charlas y además, el poder hacer llegar el contenido a personas con discapacidades auditivas. No obstante, la generación de estas transcripciones puede resultar muy costosa. Con todo esto en mente, la presente tesis tiene como objetivo proporcionar nuevas herramientas y técnicas que faciliten la transcripción de estos repositorios. En particular, abordamos el desarrollo de un conjunto de herramientas de reconocimiento de automático del habla, con énfasis en las técnicas de aprendizaje profundo que contribuyen a proporcionar transcripciones precisas en casos de estudio reales. Además, se presentan diferentes participaciones en competiciones internacionales donde se demuestra la competitividad del software comparada con otras soluciones. Por otra parte, en aras de mejorar los sistemas de reconocimiento, se propone una nueva técnica de adaptación de estos sistemas al interlocutor basada en el uso Medidas de Confianza. Esto además motivó el desarrollo de técnicas para la mejora en la estimación de este tipo de medidas por medio de Redes Neuronales Recurrentes. Todas las contribuciones presentadas se han probado en diferentes repositorios educativos. De hecho, el toolkit transLectures-UPV es parte de un conjunto de herramientas que sirve para generar transcripciones de clases en diferentes universidades e instituciones españolas y europeas.[CA] Durant els últims anys, els repositoris multimèdia en línia s'han convertit en fonts clau de coneixement gràcies a l'expansió d'Internet, especialment en l'àrea de l'educació. Institucions educatives de tot el món han dedicat molts recursos en la recerca de nous mètodes d'ensenyament, tant per millorar l'assimilació de nous coneixements, com per poder arribar a una audiència més àmplia. Com a resultat, avui dia disposem de diferents repositoris amb classes gravades que serveixen com a eines complementàries en l'ensenyament, o fins i tot poden assentar una nova base a l'ensenyament a distància. No obstant això, han de complir amb una sèrie de requisits perquè la experiència siga totalment satisfactòria i és ací on la transcripció dels materials juga un paper fonamental. La transcripció possibilita una recerca precisa dels materials en els quals l'alumne està interessat, s'obri la porta a la traducció automàtica, a funcions de recomanació, a la generació de resums de les xerrades i el poder fer arribar el contingut a persones amb discapacitats auditives. No obstant, la generació d'aquestes transcripcions pot resultar molt costosa. Amb això en ment, la present tesi té com a objectiu proporcionar noves eines i tècniques que faciliten la transcripció d'aquests repositoris. En particular, abordem el desenvolupament d'un conjunt d'eines de reconeixement automàtic de la parla, amb èmfasi en les tècniques d'aprenentatge profund que contribueixen a proporcionar transcripcions precises en casos d'estudi reals. A més, es presenten diferents participacions en competicions internacionals on es demostra la competitivitat del programari comparada amb altres solucions. D'altra banda, per tal de millorar els sistemes de reconeixement, es proposa una nova tècnica d'adaptació d'aquests sistemes a l'interlocutor basada en l'ús de Mesures de Confiança. A més, això va motivar el desenvolupament de tècniques per a la millora en l'estimació d'aquest tipus de mesures per mitjà de Xarxes Neuronals Recurrents. Totes les contribucions presentades s'han provat en diferents repositoris educatius. De fet, el toolkit transLectures-UPV és part d'un conjunt d'eines que serveix per generar transcripcions de classes en diferents universitats i institucions espanyoles i europees.[EN] During the last years, on-line multimedia repositories have become key knowledge assets thanks to the rise of Internet and especially in the area of education. Educational institutions around the world have devoted big efforts to explore different teaching methods, to improve the transmission of knowledge and to reach a wider audience. As a result, online video lecture repositories are now available and serve as complementary tools that can boost the learning experience to better assimilate new concepts. In order to guarantee the success of these repositories the transcription of each lecture plays a very important role because it constitutes the first step towards the availability of many other features. This transcription allows the searchability of learning materials, enables the translation into another languages, provides recommendation functions, gives the possibility to provide content summaries, guarantees the access to people with hearing disabilities, etc. However, the transcription of these videos is expensive in terms of time and human cost. To this purpose, this thesis aims at providing new tools and techniques that ease the transcription of these repositories. In particular, we address the development of a complete Automatic Speech Recognition Toolkit with an special focus on the Deep Learning techniques that contribute to provide accurate transcriptions in real-world scenarios. This toolkit is tested against many other in different international competitions showing comparable transcription quality. Moreover, a new technique to improve the recognition accuracy has been proposed which makes use of Confidence Measures, and constitutes the spark that motivated the proposal of new Confidence Measures techniques that helped to further improve the transcription quality. To this end, a new speaker-adapted confidence measure approach was proposed for models based on Recurrent Neural Networks. The contributions proposed herein have been tested in real-life scenarios in different educational repositories. In fact, the transLectures-UPV toolkit is part of a set of tools for providing video lecture transcriptions in many different Spanish and European universities and institutions.Agua Teba, MÁD. (2019). CONTRIBUTIONS TO EFFICIENT AUTOMATIC TRANSCRIPTION OF VIDEO LECTURES [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/130198TESISCompendi

Population-based algorithms for improved history matching and uncertainty quantification of Petroleum reservoirs

In modern field management practices, there are two important steps that shed light on a multimillion dollar investment. The first step is history matching where the simulation model is calibrated to reproduce the historical observations from the field. In this inverse problem, different geological and petrophysical properties may provide equally good history matches. Such diverse models are likely to show different production behaviors in future. This ties the history matching with the second step, uncertainty quantification of predictions. Multiple history matched models are essential for a realistic uncertainty estimate of the future field behavior. These two steps facilitate decision making and have a direct impact on technical and financial performance of oil and gas companies. Population-based optimization algorithms have been recently enjoyed growing popularity for solving engineering problems. Population-based systems work with a group of individuals that cooperate and communicate to accomplish a task that is normally beyond the capabilities of each individual. These individuals are deployed with the aim to solve the problem with maximum efficiency. This thesis introduces the application of two novel population-based algorithms for history matching and uncertainty quantification of petroleum reservoir models. Ant colony optimization and differential evolution algorithms are used to search the space of parameters to find multiple history matched models and, using a Bayesian framework, the posterior probability of the models are evaluated for prediction of reservoir performance. It is demonstrated that by bringing latest developments in computer science such as ant colony, differential evolution and multiobjective optimization, we can improve the history matching and uncertainty quantification frameworks. This thesis provides insights into performance of these algorithms in history matching and prediction and develops an understanding of their tuning parameters. The research also brings a comparative study of these methods with a benchmark technique called Neighbourhood Algorithms. This comparison reveals the superiority of the proposed methodologies in various areas such as computational efficiency and match quality

Brachistochronic motion of mechanical systems with nonideal constraints and applications to technical objects

Analizirano je brahistohrono kretanje materijalne tačke i sistema krutih tela u prisustvu Kulonove sile trenja primenom varijacionog računa. U slučaju brahistohronog kretanja materijalne tačke razmatran je slučaj kada se materijalna tačka kreće u vertikalnoj ravni u homogenom gravitacionom polju duž veze u obliku hrapave linije sa Kulonovim trenjem, pri čemu je početna brzina tačke različita od nule. Analiza brahistohronog kretanja tačke je sprovedena za slučaj kada se veza tretira kao zadržavajuća i za slučaj kada se veza tretira kao nezadržavajuća. Izvršena je generalizacija rezultata iz literature, koji su tretirali ovu problematiku primenim varijacionog računa u slučaju kada je početna brzina tačke jednaka nuli, uvođenjem pretpostavke o znaku normalne reakcije veze kao dodatnog ograničenja u varijacionoj formulaciji problema.The brachistochrone motion of the particle and the rigid multibody systems in the presence of Coulomb friction was analyzed by the application of variational calculus. In case of the brachistochrone motion of the particle, the case when the particle moves in the vertical plane in the homogeneous gravitational field along the coustraint in the form of a rough curve with Coulomb friction was considered, where the initial velocity of the particle was diff'erent fiom zero. The analysis of the brachistocluone ntotion of the particle was performed for the case when the constraint is treated as bilateral and for the case when the constraint is treated as unilateral. By introducing the assumption regarding the sign of the normal reaction of the constraint as an additional constraint in the variational formula of the problem, the results from the references treating these problems by variational calculus with the assumption that the initial velocity of the parlicle is equal to zero were generahzed. The equations of the brachistochroue were obtained in their parameter form, where the slope angle of the tangent on the brachistochrone curve was taken as the parameter. It was shown that the brachistochrone in the general case is a two-segment curve w'ith the initial line segment representing a free-fall parabola in nonresistant medium. The application of obtained results in the problems of optimization in a plant for transportation of granular nraterial was presented. In this technical object, the problem of minimization of losses of rnechanical energy due to the action of Coulomb friction during transporlation of granular material was analytically solved. In the brachistochrone motion of a constrained system of rigid bodies, the case when a certain number of unilateral constraints treated as real constraints with Coulomb friction are fbLrnd among the constraints imposed on the system. A general approach to solution by the application of the ntethodology used in the problem of brachistochrone motion of the particle was given. Within this chapter of the dissertation, a special type of the mechanical system with two degrees of freedom on which the analogy of solving the brachistocluone problem of this system with the brachistochrone problem of the particle considered in the first two chapters of the dissertation was analyzed. The results were obtained in the form which is suitable for illustration on specific technical objects and further numerical analysis. The application of differential evolution, as the optimization method, in solving systems of nonlinear algebraic equations was mentioned

Placeable and localizable elements in translation memory systems

Translation memory systems (TM systems) are software packages used in computer-assisted translation (CAT) to support human translators. As an example of successful natural language processing (NLP), these applications have been discussed in monographic works, conferences, articles in specialized journals, newsletters, forums, mailing lists, etc. This thesis focuses on how TM systems deal with placeable and localizable elements, as defined in 2.1.1.1. Although these elements are mentioned in the cited sources, there is no systematic work discussing them. This thesis is aimed at filling this gap and at suggesting improvements that could be implemented in order to tackle current shortcomings. The thesis is divided into the following chapters. Chapter 1 is a general introduction to the field of TM technology. Chapter 2 presents the conducted research in detail. The chapters 3 to 12 each discuss a specific category of placeable and localizable elements. Finally, chapter 13 provides a conclusion summarizing the major findings of this research project