10 research outputs found

    Adaptive facade network — Europe

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    Energy efficient buildings significantly contribute to meeting the EU climate and energy sustainability targets for 2020 as approximately one-third of all end-user energy in Europe today is consumed by space heating/cooling, ventilation and lighting of buildings. In this context, the energy performance of future building envelopes will play a key role.  The main aim of COST Action TU1403 with 120 participants from 26 European countries is to harmonise, share and disseminate technological knowledge on adaptive facades on a European level and to generate ideas for new innovative technologies and solutions

    Information-sharing outage-probability analysis of vehicular networks

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    In vehicular networks, information dissemination/sharing among vehicles is of salient importance. Although diverse mechanisms have been proposed in the existing literature, the related information credibility issues have not been investigated. Against this background, in this paper, we propose a credible information-sharing mechanism capable of ensuring that the vehicles do share genuine road traffic information (RTI). We commence with the outage-probability analysis of information sharing in vehicular networks under both a general scenario and a specific highway scenario. Closed-form expressions are derived for both scenarios, given the specific channel settings. Based on the outage-probability expressions, we formulate the utility of RTI sharing and design an algorithm for promoting the sharing of genuine RTI. To verify our theoretical analysis and the proposed mechanism, we invoke a real-world dataset containing the locations of Beijing taxis to conduct our simulations. Explicitly, our simulation results show that the spatial distribution of the vehicles obeys a Poisson point process (PPP), and our proposed credible RTI sharing mechanism is capable of ensuring that all vehicles indeed do share genuine RTI with each other

    Cross-Border Debt Recovery in the EU : a Comparative and Empirical Study on the Use of the European Uniform Procedures

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    The book evaluates the application of the first autonomous European civil procedures: the European Order for Payment and the European Small Claims Procedure. The study offers an in-depth comparative and empirical analysis of the way these instruments function in interaction with national procedures in England and Wales, France, Italy, and Romania. The analysis combines available statistics with European and national case law, together with practitioners’ experience. This approach provides a comprehensive understanding of the difficulties encountered, and of the solutions chosen to overcome procedural intricacies and to secure parties’ procedural rights. The findings create a solid basis for enhancing judicial cooperation and addressing the practical aspects related to the application of the procedures. In its conclusion, the book discusses the ongoing developments taking shape in this area, and reflects on the implications that the legal standards established by the European uniform procedures have for future developments. The book is of particular relevance for practitioners and courts applying the European Order for Payment and the European Small Claims Procedures; for European and national legislators, and policymakers working in this field; and for scholars interested in European civil procedure

    Theoretical arguments on exergy method and non-equilibrium in nuclear processes

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    The present Ph.D. thesis aims at discussing theoretical aspects and arguments concerning thermodynamic methods and applications to fission and fusion nuclear plants. All parts of the thesis are rooted in the ground of the scientific literature, and all outcomes and conclusions corroborate the conceptual building with no disprove of any foundations constituting the framework accepted and shared by the whole scientific community. Though, clarifications, extensions, generalizations and applications of concepts and definitions represent primary outcomes deemed by the author beneficial for a rational and systematic perspective of Physics and Thermodynamics in the research and applications to technological and industrial developments. This abstract attempt to summarize state-of-the-art and references, methods, achievements, original results, future perspectives and is followed by an index breaking down all sections to enable an overview on the way the thesis is organized. The mechanical aspect of the entropy-exergy relationship, together with the thermal aspect usually considered, represents the outset of the research and one of the central topics. This very aspect leads to a formulation of physical exergy and chemical exergy based on both useful work and useful heat, or useful work and useful mass, representing first outcomes based on the concept of available energy of a thermodynamic system interacting with a reservoir. By virtue of the entropy-exergy relationship, this approach suggests that a mechanical entropy contribution can be defined, in addition to the already used thermal entropy contribution, for work interaction due to pressure and volume variations. The mechanical entropy is related to energy transfer through work interaction, and it is complementary to the thermal entropy that accounts energy transfer by means of heat interaction. Then, the logical sequence to get mechanical exergy expression to evaluate useful work withdrawn from available energy is demonstrated. Based on mechanical exergy expression, the mechanical entropy set forth is deduced in a general form valid for any process. Finally, the formulation of physical exergy is proposed that summarizes the contribution of either heat or work interactions and related thermal exergy as well as mechanical exergy that both result as the outcome from the available energy of the composite of the system interacting with a reservoir. This formulation contains an additional term that takes into account the volume and, consequently, the pressure that allow to evaluate exergy with respect to the reservoir characterized by constant pressure other than constant temperature. The basis and related conclusions of this paper are not in contrast with principles and theoretical framework of thermodynamics and highlight a more extended approach to exergy definitions already reported in literature that remain the reference ground of present analysis. The literature reports that equality of temperature, equality of potential and equality of pressure between a system and a reservoir are necessary conditions for the stable equilibrium of the system-reservoir composite or, in the opposite and equivalent logical inference, that stable equilibrium is a sufficient condition for equality. A novelty of the present study is to prove that equality of temperature, potential and pressure is also a sufficient condition for stable equilibrium, in addition to necessity, implying that stable equilibrium is a condition also necessary, in addition to sufficiency, for equality. A subsequent implication is that the proof of the sufficiency of equality (or the necessity of stable equilibrium) is attained by means of the generalization of the entropy property, derived from the generalization of exergy property, which is used to demonstrate that stable equilibrium is a logical consequence of equality of generalized potential. This proof is underpinned by the Second Law statement and the Maximum-Entropy Principle based on the generalized entropy which depends on temperature, potential and pressure of the reservoir. The conclusion, based on these two novel concepts, consists of the theorem of necessity and sufficiency of stable equilibrium for equality of generalized potentials within a composite constituted by a system and a reservoir. Among all statements of Second Law, the existence and uniqueness of stable equilibrium, for each given value of energy content and composition of constituents of any system, has been adopted to define thermodynamic entropy by means of the impossibility of Perpetual Motion Machine of the Second Kind (PMM2) which is a consequence of the Second Law. Equality of temperature, chemical potential and pressure in many-particle systems are proved to be necessary conditions for the stable equilibrium. The proofs assume the stable equilibrium and derive, through the Highest-Entropy Principle, equality of temperature, chemical potential and pressure as a consequence. In this regard, a first novelty of the present research is to demonstrate that equality is also a sufficient condition, in addition to necessity, for stable equilibrium implying that stable equilibrium is a condition also necessary, in addition to sufficiency, for equality of temperature potential and pressure addressed to as generalized potential. The second novelty is that the proof of sufficiency of equality, or necessity of stable equilibrium, is achieved by means of a generalization of entropy property, derived from a generalized definition of exergy, both being state and additive properties accounting for heat, mass and work interactions of the system underpinning the definition of Highest-Generalized-Entropy Principle adopted in the proof. To complement the physical meaning and the reasons behind the need of a generalized definition of thermodynamic entropy, it is proposed a logical relation of its formulation on the base of Gibbs equation expressing the First Law. Moreover, a step forward is the extension of the canonical Equation of State in the perspective of thermal and chemical aspect of microscopic configurations of a system related to inter-particle kinetic energy and inter-particle potential energy determining macroscopic parameters. As a consequence, a generalized State Equation is formulated accounting for thermal, chemical and mechanical thermodynamic potentials characterizing any system in any state. As far as the Non-Equilibrium Thermodynamic is concerned, the present research aims at discussing the hierarchical structure of so-called mesoscopic systems configuration. In this regard, thermodynamic and informational aspects of entropy concept are highlighted to propose a unitary perspective of its definitions as an inherent property of any system in any state, both physical and informational. The dualism and the relation between physical nature of information and the informational content of physical states of matter and phenomena play a fundamental role in the description of multi-scale systems characterized by hierarchical configurations. A method is proposed to generalize thermodynamic and informational entropy property and characterize the hierarchical structure of its canonical definition at macroscopic and microscopic levels of a system described in the domain of classical and quantum physics. The conceptual schema is based on dualisms and symmetries inherent to the geometric and kinematic configurations and interactions occurring in many-particle and few-particle thermodynamic systems. The hierarchical configuration of particles and sub-particles, representing the constitutive elements of physical systems, breaks down into levels characterized by particle masses subdivision, implying positions and velocities degrees of freedom multiplication. This hierarchy accommodates the allocation of phenomena and processes from higher to lower levels in the respect of the equipartition theorem of energy. However, the opposite and reversible process, from lower to higher level, is impossible by virtue of the Second Law, expressed as impossibility of Perpetual Motion Machine of the Second Kind (PMM2) remaining valid at all hierarchical levels, and the non-existence of Maxwell’s demon. Based on the generalized definition of entropy property, the hierarchical structure of entropy contribution and production balance, determined by degrees of freedom and constraints of systems configuration, is established. Moreover, as a consequence of the Second Law, the non-equipartition theorem of entropy is enunciated, which would be complementary to the equipartition theorem of energy derived from the First Law. A section is specifically dedicated to specialize Second Law analyses to characterize balances of properties, and efficiencies of processes, occurring in elemental fission and fusion nuclear reactions. The conceptual schema is underpinned by the paradigm of microscopic few-particle systems and the inter-particle kinetic energy and binding potential energy determined by interactions among atomic nuclei and subatomic particles in non-equilibrium states along irreversible phenomena. The definition here proposed for thermodynamic entropy calculation is based on energy and exergy both being measurable properties by means of those values calculated from particles mass defect and used to directly derive entropy balances along nuclear processes occurring in operating industrial plants. Finally, it is proposed a preliminary exergy analysis of EU DEMO pulsed fusion power plant considering the Primary Heat Transfer Systems, the Intermediate Heat Transfer System (IHTS) including the Energy Storage System (ESS) as a first option to ensure the continuity of electric power released to the grid. A second option here considered is a methane fired auxiliary boiler replacing the ESS. The Power Conversion System (PCS) performance is evaluated as well in the overall balance. The performance analysis is based on the exergy method to correctly assess the amount of exergy destruction determined by irreversible phenomena along the whole cyclic process. The pulse and dwell phases of the reactor operation are evaluated considering the state of the art of the ESS adopting molten salts alternate heating and storage in a hot tank followed by a cooling and recovery of molten salt in a cold tank to ensure the continuity of power release to the electrical grid. An alternative plant configuration is evaluated on the basis of an auxiliary boiler replacing the ESS with a 10% of the power produced by the reactor during pulse mode. The conclusive summary of main achievements and original outcomes is followed by proposals of future developments in different fields of theoretical and applied research and technology. These themes represent an outlook on the opportunities and initiatives originating from the passionate dedication effort spent along the here ended Doctorate

    Entropic Characterization and Time Evolution of Complex Networks

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    In this thesis, we address problems encountered in complex network analysis using graph theoretic methods. The thesis specifically centers on the challenge of how to characterize the structural properties and time evolution of graphs. We commence by providing a brief roadmap for our research in Chapter 1, followed by a review of the relevant research literature in Chapter 2. The remainder of the thesis is structured as follows. In Chapter 3, we focus on the graph entropic characterizations and explore whether the von Neumann entropy recently defined only on undirected graphs, can be extended to the domain of directed graphs. The substantial contribution involves a simplified form of the entropy which can be expressed in terms of simple graph statistics, such as graph size and vertex in-degree and out-degree. Chapter 4 further investigates the uses and applications of the von Neumann entropy in order to solve a number of network analysis and machine learning problems. The contribution in this chapter includes an entropic edge assortativity measure and an entropic graph embedding method, which are developed for both undirected and directed graphs. The next part of the thesis analyzes the time-evolving complex networks using physical and information theoretic approaches. In particular, Chapter 5 provides a thermodynamic framework for handling dynamic graphs using ideas from algebraic graph theory and statistical mechanics. This allows us to derive expressions for a number of thermodynamic functions, including energy, entropy and temperature, which are shown to be efficient in identifying abrupt structural changes and phase transitions in real-world dynamical systems. Chapter 6 develops a novel method for constructing a generative model to analyze the structure of labeled data, which provides a number of novel directions to the study of graph time-series. Finally, in Chapter 7, we provide concluding remarks and discuss the limitations of our methodologies, and point out possible future research directions

    Analyse des graphes de reactions biochimiques avec une application au réseau metabolique de la cellule de plante

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    Nowadays, systems biology are facing the challenges of analysing the huge amount of biological data and large-scale metabolic networks. Although several methods have been developed in recent years to solve this problem, it is existing hardness in studying these data and interpreting the obtained results comprehensively. This thesis focuses on analysis of structural properties, computation of elementary flux modes and determination of minimal cut sets of the heterotrophic plant cellmetabolic network. In our research, we have collaborated with biologists to reconstructa mid-size metabolic network of this heterotrophic plant cell. This network contains about 90 nodes and 150 edges. First step, we have done the analysis of structural properties by using graph theory measures, with the aim of finding its owned organisation. The central points orhub reactions found in this step do not explain clearly the network structure. The small-world or scale-free attributes have been investigated, but they do not give more useful information. In the second step, one of the promising analysis methods, named elementary flux modes, givesa large number of solutions, around hundreds of thousands of feasible metabolic pathways that is difficult to handle them manually. In the third step, minimal cut sets computation, a dual approach of elementary flux modes, has been used to enumerate all minimal and unique sets of reactions stopping the feasible pathways found in the previous step. The number of minimal cut sets has a decreasing trend in large-scale networks in the case of growing the network size. We have also combined elementary flux modes analysis and minimal cut sets computation to find the relationship among the two sets of results. The findings reveal the importance of minimal cut sets in use of seeking the hierarchical structure of this network through elementary flux modes. We have set up the circumstance that what will be happened if glucose entry is absent. Bi analysis of small minimal cut sets we have been able to found set of reactions which has to be present to produce the different sugars or metabolites of interest in absence of glucose entry. Minimal cut sets of size 2 have been used to identify 8 reactions which play the role of the skeleton/core of our network. In addition to these first results, by using minimal cut sets of size 3, we have pointed out five reactions as the starting point of creating a new branch in creationof feasible pathways. These 13 reactions create a hierarchical classification of elementary flux modes set. It helps us understanding more clearly the production of metabolites of interest inside the plant cell metabolism.Aujourd’hui, la biologie des systèmes est confrontée aux défis de l’analyse de l’énorme quantité de données biologiques et à la taille des réseaux métaboliques pour des analyses à grande échelle. Bien que plusieurs méthodes aient été développées au cours des dernières années pour résoudre ce problème, ce sujet reste un domaine de recherche en plein essor. Cette thèse se concentre sur l’analyse des propriétés structurales, le calcul des modes élémentaires de flux et la détermination d’ensembles de coupe minimales du graphe formé par ces réseaux. Dans notre recherche, nous avons collaboré avec des biologistes pour reconstruire un réseau métabolique de taille moyenne du métabolisme cellulaire de la plante, environ 90 noeuds et 150 arêtes. En premier lieu, nous avons fait l’analyse des propriétés structurelles du réseau dans le but de trouver son organisation. Les réactions points centraux de ce réseau trouvés dans cette étape n’expliquent pas clairement la structure du réseau. Les mesures classiques de propriétés des graphes ne donnent pas plus d’informations utiles. En deuxième lieu, nous avons calculé les modes élémentaires de flux qui permettent de trouver les chemins uniques et minimaux dans un réseau métabolique, cette méthode donne un grand nombre de solutions, autour des centaines de milliers de voies métaboliques possibles qu’il est difficile de gérer manuellement. Enfin, les coupes minimales de graphe, ont été utilisés pour énumérer tous les ensembles minimaux et uniques des réactions qui stoppent les voies possibles trouvées à la précédente étape. Le nombre de coupes minimales a une tendance à ne pas croître exponentiellement avec la taille du réseau a contrario des modes élémentaires de flux. Nous avons combiné l’analyse de ces modes et les ensembles de coupe pour améliorer l’analyse du réseau. Les résultats montrent l’importance d’ensembles de coupe pour la recherche de la structure hiérarchique du réseau à travers modes de flux élémentaires. Nous avons étudié un cas particulier : qu’arrive-t-il si on stoppe l’entrée de glucose ? En utilisant les coupes minimales de taille deux, huit réactions ont toujours été trouvés dans les modes élémentaires qui permettent la production des différents sucres et métabolites d’intérêt au cas où le glucose est arrêté. Ces huit réactions jouent le rôle du squelette / coeur de notre réseau. En élargissant notre analyse aux coupes minimales de taille 3, nous avons identifié cinq réactions comme point de branchement entre différent modes. Ces 13 réactions créent une classification hiérarchique des modes de flux élémentaires fixés et nous ont permis de réduire considérablement le nombre de cas à étudier (approximativement divisé par 10) dans l’analyse des chemins réalisables dans le réseau métabolique. La combinaison de ces deux outils nous a permis d’approcher plus efficacement l’étude de la production des différents métabolites d’intérêt par la cellule de plante hétérotrophique
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