39 research outputs found

    Checking Trustworthiness of Probabilistic Computations in a Typed Natural Deduction System

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    In this paper we present the probabilistic typed natural deduction calculus TPTND, designed to reason about and derive trustworthiness properties of probabilistic computational processes, like those underlying current AI applications. Derivability in TPTND is interpreted as the process of extracting nn samples of possibly complex outputs with a certain frequency from a given categorical distribution. We formalize trust for such outputs as a form of hypothesis testing on the distance between such frequency and the intended probability. The main advantage of the calculus is to render such notion of trustworthiness checkable. We present a computational semantics for the terms over which we reason and then the semantics of TPTND, where logical operators as well as a Trust operator are defined through introduction and elimination rules. We illustrate structural and metatheoretical properties, with particular focus on the ability to establish under which term evolutions and logical rules applications the notion of trustworhtiness can be preserved

    8th International Conference on Ambient Systems, Networks and Technologies, ANT-2017 and the 7th International Conference on Sustainable Energy Information Technology, SEIT 2017, 16-19 May 2017, Madeira, Portugal

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    The common approach enabling a resource constrained device to get connected to the Internet is through programming instructions and transferring it to an embedded device. This procedure involves various tools and cross-compiling of the code depending on the platform architecture. In practical IoT applications, where a huge number of nodes exist, this process becomes almost impossible due to the heterogeneous platforms and protocols involved and the deployment conditions. This paper introduces a flexible and scalable approach that enhances modifiability and programmability through client-server-server-client architecture. It allows changing the behavior of the system after deployment through a lightweight script written with a domain specific language, DoS-IL, and stored in a gateway at the fog layer. An embedded resource browser is used to request and execute the script. The results of analysis for this model and the tools developed along the way are discussed. 1877-0509 (C) 2017 The Authors. Published by Elsevier B.V.</p

    Security and Trust in Safety Critical Infrastructures

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    Critical infrastructures such as road vehicles and railways are undergoing a major change, which increases the dependency of their operation and control on Information Technology (IT) and makes them more vulnerable to malicious intent. New complex communication infrastructures emerge using the increased connectivity of these safety-critical systems to enable efficient management of operational processes, service provisioning, and information exchange for various (third-party) actors. Railway Command and Control Systems (CCSs) turn with the introduction of digital interlocking into an “Internet of Railway Things”, where safety-critical railway signaling components are deployed on common-purpose platforms and connected via standard IP-based networks. Similarly, the mass adoption of Electric Vehicles (EVs) and the need to supply their batteries with energy for charging has given rise to a Vehicle-to-Grid (V2G) infrastructure, which connects vehicles to power grids and multiple service providers to coordinate charging and discharging processes and maintain grid stability under varying power demands. The Plug-and-Charge feature brought in by the V2G communication standard ISO 15118 allows an EV to access charging and value-added services, negotiate charging schedules, and support the grid as a distributed energy resource in a largely automated way, by leveraging identity credentials installed in the vehicle for authentication and payment. The fast deployment of this advanced functionality is driven by economical and political decisions including the EU Green Deal for climate neutrality. Due to the complex requirements and long standardization and development cycles, the standards and regulations, which play the key role in operating and protecting critical infrastructures, are under pressure to enable the timely and cost-effective adoption. In this thesis, we investigate security and safety of future V2G and railway command and control systems with respect to secure communication, platform assurance as well as safety and security co-engineering. One of the major goals in this context is the continuous collaboration and establishment of the proposed security solutions in upcoming domain-specific standards, thus ensuring their practical applicability and prompt implementation in real-world products. We first analyze the security of V2G communication protocols and requirements for secure service provisioning via charging connections. We propose a new Plug-and-Patch protocol that enables secure update of EVs as a value-added service integrated into the V2G charging loop. Since EVs can also participate in energy trading by storing and feeding previously stored energy to grid, home, or other vehicles, we then investigate fraud detection methods that can be employed to identify manipulations and misbehaving users. In order to provide a strong security foundation for V2G communications, we propose and analyze three security architectures employing a hardware trust anchor to enable trust establishment in V2G communications. We integrate these architectures into standard V2G protocols for load management, e-mobility services and value-added services in the V2G infrastructure, and evaluate the associated performance and security trade-offs. The final aspect of this work is safety and security co-engineering, i.e., integration of safety and security processes vital for the adequate protection of connected safety-critical systems. We consider two application scenarios, Electric Vehicle Charging System (EVCS) and Object Controller (OC) in railway CCS, and investigate how security methods like trusted computing can be applied to provide both required safety and security properties. In the case of EVCS, we bind the trust boundary for safety functionality (certified configuration) to the trust boundary in the security domain and design a new security architecture that enforces safety properties via security assertions. For the railway use case, we focus on ensuring non-interference (separation) between these two domains and develop a security architecture that allows secure co-existence of applications with different criticality on the same hardware platform. The proposed solutions have been presented to the committee ISO/TC 22/SC 31/JWG 1 that develops the ISO 15118 standard series and to the DKE working group “Informationssicherheit für Elektromobilität” responsible for the respective application guidelines. Our security extension has been integrated in the newest edition ISO 15118-20 released in April 2022. Several manufacturers have already started concept validation for their future products using our results. In this way, the presented analyses and techniques are fundamental contributions in improving the state of security for e-mobility and railway applications, and the overall resilience of safety-critical infrastructures to malicious attacks

    ECOS 2012

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    The 8-volume set contains the Proceedings of the 25th ECOS 2012 International Conference, Perugia, Italy, June 26th to June 29th, 2012. ECOS is an acronym for Efficiency, Cost, Optimization and Simulation (of energy conversion systems and processes), summarizing the topics covered in ECOS: Thermodynamics, Heat and Mass Transfer, Exergy and Second Law Analysis, Process Integration and Heat Exchanger Networks, Fluid Dynamics and Power Plant Components, Fuel Cells, Simulation of Energy Conversion Systems, Renewable Energies, Thermo-Economic Analysis and Optimisation, Combustion, Chemical Reactors, Carbon Capture and Sequestration, Building/Urban/Complex Energy Systems, Water Desalination and Use of Water Resources, Energy Systems- Environmental and Sustainability Issues, System Operation/ Control/Diagnosis and Prognosis, Industrial Ecology

    Sistema cooperativo de planificación de demanda de electricidad agregada: Comunidades sostenibles que optimizan el consumo de renovables

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    Hoy en día, la eficiencia energética aparece como eje fundamental para combatir el cambio climático y reducir nuestra huella de carbono. En este sentido, el rol del ciudadano y las decisiones de los consumidores con respecto a su estilo de vida, como el uso de vehículos híbridos o eléctricos, el consumo de alimentos procedentes de agricultura sostenible y una gestión eficiente de la energía en hogares son piezas claves para promover una nueva realidad de energía sostenible. Instituciones públicas están prestando programas de ayuda para la modernización de equipamiento, y financiando reformas hacia una mayor eficiencia energética en hogares, instalaciones públicas y edificios residenciales. Por su parte, Red Eléctrica promueve un nuevo modelo energético, estimulado por Directivas Europeas, en el que la gestión de la flexibilidad de demanda, el fomento de autoconsumo y almacenamiento procedente de fuentes renovables, así como la integración del consumidor en servicios de balanceo son iniciativas reales. La conocida como comunidad inteligente surge como evolución del paradigma de las ciudades inteligentes y supone un enfoque centrado en las personas en el que los ciudadanos aspiran a lograr objetivos comunes. Este paradigma, junto con los electrodomésticos inteligentes y otros dispositivos conectados en la Internet de las cosas, han aumentado las expectativas en las tecnologías TIC para la consecución y mayor aceptación de programas de eficiencia energética como la Respuesta de Demanda. Estos programas buscan balancear suministro y demanda energética, reducir emisiones, promover la integración de las energías renovables y fomentar un cambio en el comportamiento del consumidor. Esta tesis doctoral surge de la necesidad de diseñar, desarrollar, implantar y medir los beneficios derivados de la gestión de la demanda mediante una solución tecnológica que ayude a los consumidores a administrar su demanda y su flexibilidad. Para ello, se diseña un algoritmo de planificación de la demanda agregada de electricidad en una comunidad de consumidores y un controlador de sus electrodomésticos conectados. Esta agregación se optimiza gracias a una función objetivo que se alimenta con la oferta disponible de energía renovable. La solución se implementa en plataformas ligeras y económicas, y se valida en entornos de laboratorio cumpliendo estrictos requisitos de rendimiento, fiabilidad, calidad de servicio y seguridad. Escenarios emulados en prototipos ofrecen resultados muy eficientes y realistas y permiten reconocer un conjunto de tres patrones de comportamiento en comunidades de consumidores construidas sobre un conjunto de datos de consumo real. La flexibilidad, el volumen y curva de demanda son factores determinantes para una planificación más efectiva y eficiente de la demanda total de la comunidad. La identificación, por experto y por aprendizaje automático, de estos patrones ayuda a definir y predecir una mejor estrategia en el desarrollo de programas de gestión de demanda y de agregación en comunidades reales que busquen cooperativamente maximizar el aprovechamiento de fuentes renovables además de fomentar un cambio en el comportamiento del consumidor hacia un consumo más sostenible y eficiente

    Constructing pedestrian-centric street mobility: Observation and simulation for design

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    There are three principal components to the research presented in this thesis: a video-observation study of pedestrian behaviours and interactions with traffic, leading to the development of an agent-based digital simulation, and demonstrating the potential of this simulation for designing pedestrian-centric interventions in the streetscape. The long-term objective is to devise streetscapes that responsively adapt to the needs of pedestrians. Since the advent of car culture in the late 1930s, the approaches to street design have prioritised efficient motorised traffic flow, restricting walking and neglecting the pedestrian point of view. In recent years, however, a growing interest in making urban spaces more pedestrian-friendly has emerged, popularising concepts such as walkability, shared space, and traffic calming. These approaches aim to promote active travel and reduce car dependency in order to mitigate congestion, pollution, accidents and other harms. Urban studies have concentrated primarily on pedestrian-only zones and utilised spatial features as a way to reach pedestrian-friendly streets. Meanwhile, transport studies have tended to approach the street from a throughput and vehicle-oriented stance. Despite these endeavours, pedestrian-oriented approaches appear to lack systematic consideration of pedestrian behaviours as they interact with motor vehicles and street infrastructure. My PhD research differs from prior studies by focusing on these behaviours and interactions to support a pedestrian-oriented street mobility system. The current design of streets communicates to pedestrians via its structures and signs, such as barriers, crossings, and lights, while its capacity to respond and adapt is minimal. In contrast, this thesis argues that, since the street environment is inherently dynamic, we should analyse its dynamics and design the street to be responsive. Through responsiveness, my aim is to increase the convenience of pedestrian movement whilst creating a safe experience. This PhD asks the question 'how to design a pedestrian-centric street system that dynamically manages street mobility?'. The research takes a practice-based and reflective approach, designing agent-based simulations based on a qualitative observational study. Designing a simulation accomplishes two things: 1) it creates a space for implementing and evaluating possible design interventions, and 2) it prompts new insights into the behavioural processes of pedestrians. My research has followed an iterative cycle in line with second-order cybernetics: in two feedback loops, the first study informed the second study while the second informed the first. The video observation of street behaviours particularly explored pedestrian decision and interaction processes, identifying pedestrians’ own observational strategies and their varying levels of risk-taking. These aspects are reflected in the simulation. The first chapter introduces the pedestrian issues on the street and sets out the key concepts in pedestrian-centric street design. The second chapter examines the literature and existing practice that addresses pedestrian and vehicle interactions on the street. Chapter three sets out the theoretical framework and the following chapter describes the methodology. The three subsequent chapters present the following studies: (1) understanding the context by conducting qualitative video observation in a real street environment to observe and document the relations between streets, pedestrians and vehicles; (2) creating an artificial pedestrian society for simulation purposes, using agent-based modelling, both to refine the understanding developed through video analysis and to create a platform for experimentation; (3) design and implementation of prototype responsive interventions within the simulation, focusing on localised changes in the environment to empower pedestrians. The last chapter reflects on these projects by discussing the research contributions in terms of methods, techniques, and practices. The methodological innovation includes combining qualitative and computational tools as well as the use of simulation and video analysis in an iterative and reflexive cycle. Theoretical contributions include evaluating streets through pedestrian dynamics, creating a taxonomy of existing pedestrian interventions according to their spatial and temporal impacts, and rethinking the street as a responsive environment. The practical component advances the technical state of the art by expanding the capabilities of pedestrian agents when negotiating with vehicles and making crossing decisions and demonstrates the potential for designing novel interventions in the streetscape, including those that respond to pedestrian behaviour. The last chapter, also, emphasises the role of reflective design practice and the place of simulation within it

    The Impact of Digital Technologies on Public Health in Developed and Developing Countries

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    This open access book constitutes the refereed proceedings of the 18th International Conference on String Processing and Information Retrieval, ICOST 2020, held in Hammamet, Tunisia, in June 2020.* The 17 full papers and 23 short papers presented in this volume were carefully reviewed and selected from 49 submissions. They cover topics such as: IoT and AI solutions for e-health; biomedical and health informatics; behavior and activity monitoring; behavior and activity monitoring; and wellbeing technology. *This conference was held virtually due to the COVID-19 pandemic

    Differences in Perceived Information Sensitivity During Smartphones Use Among UK University Graduates

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    The level of sensitivity with which smartphone users perceive information influences their privacy decisions. Information sensitivity is complex to understand due to the multiple factors influencing it. Adding to this complexity is the intimate nature of smartphone usage that produces personal information about various aspects of users’ lives. Users’ perceive information differently and this plays an important role in determining responses to privacy risk. The different levels of perceived sensitivity in turn point out how users could be uniquely supported through information cues that will enhance their privacy. However, several studies have tried to explain information sensitivity and privacy decisions by focusing on single-factor analysis. The current research adopts a different approach by exploring the influences of the disclosure context (smartphone ecosystem), three critical factors (economic status, location tracking, apps permission requests) and privacy attributes (privacy guardian, pragmatist, and privacy unconcerned) for a more encompassing understanding of how smartphone user-categories in the UK perceive information. The analysis of multiple factors unearths deep complexities and provides nuanced understanding of how information sensitivity varies across categories of smartphone users. Understanding how user-categories perceive information enables tailored privacy. Tailored privacy moves from “one-size-fits-all” to tailoring support to users and their context. The present research applied the Struassian grounded theory to analyse the qualitative interview data collected from 47 UK university graduates who are smartphone users. The empirical research findings show that smartphone users can be characterised into eight categories. However, the category a user belongs depends on the influencing factor or the information (identity or financial) involved and the privacy concern category of the user. This study proposes a middle-range theory for understanding smartphone users’ perception of information sensitivity. Middle-range theories are testable propositions resulting from in-depth focus on a specific subject matter by looking at the attributes of individuals. The propositions shows that an effective privacy support model for smartphone users should consider the varying levels of information sensitivity. Therefore, the study argues that users who perceive information as highly sensitive require privacy assurance to strengthen privacy, whereas users who perceive information as less sensitive require appropriate risk awareness to mitigate privacy risks. The proposition provides the insight that could support tailored privacy for smartphone users

    Envisioning Model-Based Performance Engineering Frameworks.

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    Abstract Our daily activities depend on complex software systems that must guarantee certain performance. Several approaches have been devised in the last decade to validate software systems against performance requirements. However, software designers still encounter problems in the interpretation of performance analysis results (e.g., mean values, probability distribution functions) and in the definition of design alternatives (e.g., to split a software component in two and redeploy one of them) aimed at fulfilling performance requirements. This paper describes a general model-based performance engineering framework to support designers in dealing with such problems aimed at enhancing the system. The framework relies on a formalization of the knowledge needed in order to characterize performance flaws and provide alternative system design. Such knowledge can be instantiated based on the techniques devised for interpreting performance analysis results and providing feedback to designers. Three techniques are considered in this paper for instantiating the framework and the main challenges to face during such process are pointed out and discussed
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