428 research outputs found

    Optimization based energy-efficient control inmobile communication networks

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    In this work we consider how best to control mobility and transmission for the purpose of datatransfer and aggregation in a network of mobile autonomous agents. In particular we considernetworks containing unmanned aerial vehicles (UAVs). We first consider a single link betweena mobile transmitter-receiver pair, and show that the total amount of transmittable data isbounded. For certain special, but not overly restrictive cases, we can determine closed-formexpressions for this bound, as a function of relevant mobility and communication parameters.We then use nonlinear model predictive control (NMPC) to jointly optimize mobility and trans-mission schemes of all networked nodes for the purpose of minimizing the energy expenditureof the network. This yields a novel nonlinear optimal control problem for arbitrary networksof autonomous agents, which we solve with state-of-the-art nonlinear solvers. Numerical re-sults demonstrate increased network capacity and significant communication energy savingscompared to more na ̈Ĺve policies. All energy expenditure of an autonomous agent is due tocommunication, computation, or mobility and the actual computation of the NMPC solutionmay be a significant cost in both time and computational resources. Furthermore, frequentbroadcasting of control policies throughout the network can require significant transmit andreceive energies. Motivated by this, we develop an event-triggering scheme which accounts forthe accuracy of the optimal control solution, and provides guarantees of the minimum timebetween successive control updates. Solution accuracy should be accounted for in any triggeredNMPC scheme where the system may be run in open loop for extended times based on pos-sibly inaccurate state predictions. We use this analysis to trade-off the cost of updating ourtransmission and locomotion policies, with the frequency by which they must be updated. Thisgives a method to trade-off the computation, communication and mobility related energies ofthe mobile autonomous network.Open Acces

    Dynamic Formation and Strategic Management of Web Services Communities

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    In the last few years, communities of services have been studied in a certain numbers of proposals as virtual pockets of similar expertise. The motivation is to provide these services with high chance of discovery through better visibility, and to enhance their capabilities when it comes to provide requested functionalities. There are some proposed mechanisms and models on aggregating web services and making them cooperate within their communities. However, forming optimal and stable communities as coalitions to maximize individual and group efficiency and income for all the involved parties has not been addressed yet. Moreover, in the proposed frameworks of these communities, a common assumption is that residing services, which are supposed to be autonomous and intelligent, are competing over received requests. However, those services can also exhibit cooperative behaviors, for instance in terms of substituting each other. When competitive and cooperative behaviors and strategies are combined, autonomous services are said to be "coopetitive". Deciding to compete or cooperate inside communities is a problem yet to be investigated. In this thesis, we first identify the problem of defining efficient algorithms for coalition formation mechanisms. We study the community formation problem in two different settings: 1) communities with centralized manager having complete information using cooperative game-theoretic techniques; and 2) communities with distributed decision making mechanisms having incomplete information using training methods. We propose mechanisms for community membership requests and selections of web services in the scenarios where there is interaction between one community and many web services and scenarios where web services can join multiple established communities. Then in order to address the coopetitive relation within communities of web services, we propose a decision making mechanism for our web services to efficiently choose competition or cooperation strategies to maximize their payoffs. We prove that the proposed decision mechanism is efficient and can be implemented in time linear in the length of the time period considered for the analysis and the number of services in the community. Moreover, we conduct extensive simulations, analyze various scenarios, and confirm the obtained theoretical results using parameters from a real web services dataset

    A room of one\u27s own, revisited: An existential-hermeneutic study of female solitude

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    This study presents an existential-hermeneutic analysis of nine women\u27s first-person accounts of extended periods of solitude. The accounts were analyzed along the five existential dimensions of spatiality, temporality, embodiment, language, and co-existentiality, producing a rich portrait of the women\u27s lived experience of solitude. One of the first-person accounts was provided by the author of the study, who underwent three solitary retreats in the interest of this project, adding an autoethnographic component to the work. Theory from the existential-phenomenological, monastic, ecopsychological, and feminist literatures was applied to the data, enabling us to interpret the significance of the shifts the women experienced through an interdisciplinary set of lenses. The women experienced both subtle and profound shifts in their senses of self and modes of being in the world over the course of their retreats. In the absence of direct human relations, the women developed greater intimacy with things, non-human beings, and the Divine. Through the practice of simplicity, the women cultivated humility and more contemplative modes of seeing, revealing previously hidden contours of the material world and fostering a child-like sense of wonder. By leaving clock time and slowing down, the women became increasingly oriented toward the present moment, entrained to the rhythms of the natural world, and attuned to their desire. By retreating from the gaze of the (human) other, the women worked to heal a sense of alienation from their own bodies, experienced a respite from feminine performativity, and came to move through the world more seamlessly and comfortably. And by observing silence, the women cultivated the ability to listen beyond the human conversation and the chattering of their own minds, developed a more sacred relationship to language, confronted their emotional demons, and found themselves increasingly drawn toward the poetic. Overall, through their solitudes, the women developed a greater stance of receptivity toward the more-than-human world, deconstructed elements of identity and modes of being aligned with the false self, and recovered aspects of their lived experience which had been neglected or suppressed over the course of becoming an adult, and especially a woman, in the context of contemporary American culture

    Foundations for practical network verification

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    Computer networks are large and complex and the often manual process of configuring such systems is error-prone, leading to network outages and breaches. This has ignited research into network verification tools that given a set of operator intents, automatically check whether the configured network satisfies the intents. In this dissertation, we argue that existing works in this area have important limitations that prevent their widespread adoption in the real world. We set to address these limitations by revisiting the main aspects of network verification: verification framework, intent specification, and network modeling. First, we develop #PEC, a symbolic packet header analysis framework that resolves the tension between expressiveness and efficiency in previous works. We provide an extensible library of efficient match-types that allows encoding and analyzing more types of forwarding rules (e.g. Linux iptables) compared to most previous works. Similar to the state-of-the-art, #PEC partitions the space of packet headers into a set of equivalence classes (PECs) before the analysis. However, it uses a lattice-based approach to do so, refraining from using computationally expensive negation and subtraction operations. Our experiments with a broad range of real-world datasets show that #PEC is 10× faster than similarly expressive state-of-the-art. We also demonstrate how empty PECs in previous works lead to unsound/incomplete analysis and develop a counting-based method to eliminate empty PECs from #PEC that outperforms baseline approaches by 10 − 100×. Next, we note that network verification requires formal specifications of the intents of the network operator as a starting point, which are almost never available or even known in a complete form. We mitigate this problem by providing a framework to utilize existing low-level network behavior to infer the high-level intents. We design Anime, a system that given observed packet forwarding behavior, mines a compact set of possible intents that best describe the observations. Anime accomplishes this by applying optimized clustering algorithms to a set of observed network paths, encoded using path features with hierarchical values that yield a way to control the precision-recall tradeoff. The resulting inferred intents can be used as input to verification/synthesis tools for continued maintenance. They can also be viewed as a summary of network behavior, and as a way to find anomalous behavior. Our experiments, including data from an operational network, demonstrate that Anime produces higher quality (F-score) intents than past work, can generate compact summaries with minimal loss of precision, is resilient to imperfect input and policy changes, scales to large networks, and finds actionable anomalies in an operational network. Finally, we turn our attention to modeling networking devices. We envision basing data plane analysis on P4 as the modeling language. Unlike most tools, we believe P4 analysis must be based on a precise model of the language rather than its informal specification. To this end, we develop a formal operational semantics of the P4 language during the process of which we have identified numerous issues with the design of the language. We then provide a suite of formal analysis tools derived directly from our semantics including an interpreter, a symbolic model checker, a deductive program verifier, and a program equivalence checker. Through a set of case studies, we demonstrate the use of our semantics beyond just a reference model for the language. This includes applications for the detection of unportable code, state-space exploration, search for bugs, full functional verification, and compiler translation validation

    Multispace & Multistructure. Neutrosophic Transdisciplinarity (100 Collected Papers of Sciences), Vol. IV

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    The fourth volume, in my book series of “Collected Papers”, includes 100 published and unpublished articles, notes, (preliminary) drafts containing just ideas to be further investigated, scientific souvenirs, scientific blogs, project proposals, small experiments, solved and unsolved problems and conjectures, updated or alternative versions of previous papers, short or long humanistic essays, letters to the editors - all collected in the previous three decades (1980-2010) – but most of them are from the last decade (2000-2010), some of them being lost and found, yet others are extended, diversified, improved versions. This is an eclectic tome of 800 pages with papers in various fields of sciences, alphabetically listed, such as: astronomy, biology, calculus, chemistry, computer programming codification, economics and business and politics, education and administration, game theory, geometry, graph theory, information fusion, neutrosophic logic and set, non-Euclidean geometry, number theory, paradoxes, philosophy of science, psychology, quantum physics, scientific research methods, and statistics. It was my preoccupation and collaboration as author, co-author, translator, or cotranslator, and editor with many scientists from around the world for long time. Many topics from this book are incipient and need to be expanded in future explorations

    Emergent Design

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    Explorations in Systems Phenomenology in Relation to Ontology, Hermeneutics and the Meta-dialectics of Design SYNOPSIS A Phenomenological Analysis of Emergent Design is performed based on the foundations of General Schemas Theory. The concept of Sign Engineering is explored in terms of Hermeneutics, Dialectics, and Ontology in order to define Emergent Systems and Metasystems Engineering based on the concept of Meta-dialectics. ABSTRACT Phenomenology, Ontology, Hermeneutics, and Dialectics will dominate our inquiry into the nature of the Emergent Design of the System and its inverse dual, the Meta-system. This is an speculative dissertation that attempts to produce a philosophical, mathematical, and theoretical view of the nature of Systems Engineering Design. Emergent System Design, i.e., the design of yet unheard of and/or hitherto non-existent Systems and Metasystems is the focus. This study is a frontal assault on the hard problem of explaining how Engineering produces new things, rather than a repetition or reordering of concepts that already exist. In this work the philosophies of E. Husserl, A. Gurwitsch, M. Heidegger, J. Derrida, G. Deleuze, A. Badiou, G. Hegel, I. Kant and other Continental Philosophers are brought to bear on different aspects of how new technological systems come into existence through the midwifery of Systems Engineering. Sign Engineering is singled out as the most important aspect of Systems Engineering. We will build on the work of Pieter Wisse and extend his theory of Sign Engineering to define Meta-dialectics in the form of Quadralectics and then Pentalectics. Along the way the various ontological levels of Being are explored in conjunction with the discovery that the Quadralectic is related to the possibility of design primarily at the Third Meta-level of Being, called Hyper Being. Design Process is dependent upon the emergent possibilities that appear in Hyper Being. Hyper Being, termed by Heidegger as Being (Being crossed-out) and termed by Derrida as Differance, also appears as the widest space within the Design Field at the third meta-level of Being and therefore provides the most leverage that is needed to produce emergent effects. Hyper Being is where possibilities appear within our worldview. Possibility is necessary for emergent events to occur. Hyper Being possibilities are extended by Wild Being propensities to allow the embodiment of new things. We discuss how this philosophical background relates to meta-methods such as the Gurevich Abstract State Machine and the Wisse Metapattern methods, as well as real-time architectural design methods as described in the Integral Software Engineering Methodology. One aim of this research is to find the foundation for extending the ISEM methodology to become a general purpose Systems Design Methodology. Our purpose is also to bring these philosophical considerations into the practical realm by examining P. Bourdieu’s ideas on the relationship between theoretical and practical reason and M. de Certeau’s ideas on practice. The relationship between design and implementation is seen in terms of the Set/Mass conceptual opposition. General Schemas Theory is used as a way of critiquing the dependence of Set based mathematics as a basis for Design. The dissertation delineates a new foundation for Systems Engineering as Emergent Engineering based on General Schemas Theory, and provides an advanced theory of Design based on the understanding of the meta-levels of Being, particularly focusing upon the relationship between Hyper Being and Wild Being in the context of Pure and Process Being

    Internet of Things Applications - From Research and Innovation to Market Deployment

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    The book aims to provide a broad overview of various topics of Internet of Things from the research, innovation and development priorities to enabling technologies, nanoelectronics, cyber physical systems, architecture, interoperability and industrial applications. It is intended to be a standalone book in a series that covers the Internet of Things activities of the IERC – Internet of Things European Research Cluster from technology to international cooperation and the global "state of play".The book builds on the ideas put forward by the European research Cluster on the Internet of Things Strategic Research Agenda and presents global views and state of the art results on the challenges facing the research, development and deployment of IoT at the global level. Internet of Things is creating a revolutionary new paradigm, with opportunities in every industry from Health Care, Pharmaceuticals, Food and Beverage, Agriculture, Computer, Electronics Telecommunications, Automotive, Aeronautics, Transportation Energy and Retail to apply the massive potential of the IoT to achieving real-world solutions. The beneficiaries will include as well semiconductor companies, device and product companies, infrastructure software companies, application software companies, consulting companies, telecommunication and cloud service providers. IoT will create new revenues annually for these stakeholders, and potentially create substantial market share shakeups due to increased technology competition. The IoT will fuel technology innovation by creating the means for machines to communicate many different types of information with one another while contributing in the increased value of information created by the number of interconnections among things and the transformation of the processed information into knowledge shared into the Internet of Everything. The success of IoT depends strongly on enabling technology development, market acceptance and standardization, which provides interoperability, compatibility, reliability, and effective operations on a global scale. The connected devices are part of ecosystems connecting people, processes, data, and things which are communicating in the cloud using the increased storage and computing power and pushing for standardization of communication and metadata. In this context security, privacy, safety, trust have to be address by the product manufacturers through the life cycle of their products from design to the support processes. The IoT developments address the whole IoT spectrum - from devices at the edge to cloud and datacentres on the backend and everything in between, through ecosystems are created by industry, research and application stakeholders that enable real-world use cases to accelerate the Internet of Things and establish open interoperability standards and common architectures for IoT solutions. Enabling technologies such as nanoelectronics, sensors/actuators, cyber-physical systems, intelligent device management, smart gateways, telematics, smart network infrastructure, cloud computing and software technologies will create new products, new services, new interfaces by creating smart environments and smart spaces with applications ranging from Smart Cities, smart transport, buildings, energy, grid, to smart health and life. Technical topics discussed in the book include: • Introduction• Internet of Things Strategic Research and Innovation Agenda• Internet of Things in the industrial context: Time for deployment.• Integration of heterogeneous smart objects, applications and services• Evolution from device to semantic and business interoperability• Software define and virtualization of network resources• Innovation through interoperability and standardisation when everything is connected anytime at anyplace• Dynamic context-aware scalable and trust-based IoT Security, Privacy framework• Federated Cloud service management and the Internet of Things• Internet of Things Application

    Spatial Auditory Maps for Blind Travellers

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    Empirical research shows that blind persons who have the ability and opportunity to access geographic map information tactually, benefit in their mobility. Unfortunately, tangible maps are not found in large numbers. Economics is the leading explanation: tangible maps are expensive to build, duplicate and distribute. SAM, short for Spatial Auditory Map, is a prototype created to address the unavail- ability of tangible maps. SAM presents geographic information to a blind person encoded in sound. A blind person receives maps electronically and accesses them using a small in- expensive digitalizing tablet connected to a PC. The interface provides location-dependent sound as a stylus is manipulated by the user, plus a schematic visual representation for users with residual vision. The assessment of SAM on a group of blind participants suggests that blind users can learn unknown environments as complex as the ones represented by tactile maps - in the same amount of reading time. This research opens new avenues in visualization techniques, promotes alternative communication methods, and proposes a human-computer interaction framework for conveying map information to a blind person

    What Support Does Information and Communication Technology (ICT) Offer to Organizational Improvisation During Crisis Response ?

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    While evidence of the exceedingly important role of technology in organizational life is commonplace, academics have not fully captured the influence of Information and Communication Technology (ICT) on crisis response. A substantive body of knowledge on technology and crisis response already exists and keeps developing. Extensive research is on track to highlight how technology helps to prepare to crisis response and develop service recovery plans. However, some aspects of crisis response remain unknown. Among all the facets of crisis response that have been under investigation for some years, improvisation still challenges academics as a core component of crisis response. In spite of numerous insights on improvisation as a cognitive process and an organizational phenomenon, the question of how improvisers do interact together while improvising remains partly unanswered. As a result, literature falls short of details on whether crisis responders can rely on technology to interact when they have to improvise collectively. This dissertation therefore brings into focus ICT support to organizational improvisation in crisis response in two steps: We first address this question from a general standpoint by reviewing literature. We then propose an in depth and contextualized analysis of the use of a restricted set of technologies – emails, faxes, the Internet, phones - during the organizational crisis provoked by the 2003 French heat wave. Our findings offer a nuanced view of ICT support to organizational improvisation in crisis response. Our theoretical investigation suggests that ICTs, in a large sense, allow crisis responders to improvise collectively. It reports ICT properties - graphical representation, modularity, calculation, many-to-many communication, data centralization and virtuality – that promote the settling of appropriate conditions for interaction during organizational improvisation in crisis response. In the empirical work, we provide a more integrative picture of ICT support to organizational improvisation in crisis response by retrospectively observing crisis responders’ interactions during the 2003 French heat wave. Our empirical findings suggest that improvisation enables crisis responders to cope with organizational emptiness that burdens crisis response. However, crisis responders’ participation in organizational improvisation depends on their communicative genres. During the 2003 French heat wave crisis, administrative actors who had developed what we call a “dispassionate” communicative genre in relation to their email use, barely participated in organizational improvisation. Conversely, improvisers mainly communicated in what we call a “fervent” communicative genre. Therefore, our findings reveal that the ICT support to organizational improvisation in crisis response is mediated by the communication practices and strategies that groups of crisis responders develop around ICT tools
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