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Digitalization for Port Decarbonization: Decarbonization of key energy processes at the Port of Tyne
No full textThis article presents findings of the Clean Tyne Project. This project was part of the Clean Maritime Demonstration, funded by the UK’s Department for Transport and delivered in partnership with Innovate UK. Announced in March 2020, and part of the Prime Minister’s Ten Point Plan to position the UK at the forefront of green shipbuilding and maritime technology, the Clean Maritime Demonstration Competition was a £20m investment from government alongside a further £10m from industry to reduce emissions from the maritime sector. The contribution of Newcastle University in the project was to provide quantifiable evidence around the benefits of digitalization, by means of a real-time supervisory and data acquisition platform, in the reduction of carbon emissions, as well as operating and infrastructural costs, at the Port of Tyne.The main aim of this article is to report and discuss the key outputs originating from the modelling performed by Newcastle University around specific operational scenarios at the port. These are intended to highlight the value of intelligent coordination of key energy processes and reduced uncertainty of associated data, both enabled by digitalization. For this purpose, we have designed and modelled current and future operational scenarios, in which Emission Reduction Technologies (ERTs)1 and infrastructure are introduced, alongside increased capability for coordination of energy assets and data availability. In our analysis we consider a centralized decision-making process where energy costs and carbon emissions are minimized subject to available infrastructure and data.Our results can be divided into three categories: impact of emission reduction technologies, impact of coordination, and impact of uncertainty on investment deferral. Under certain credible modelling and data assumptions, and considering energy operational costs and emissions, our findings are that: ERTs can yield significant emissions reductions of up to 93% in year 2040 compared to a present scenario, even if imported power is not 100% zero-carbon; energy costs related with key operations can be reduced up to 45% in year 2050 compared to a scenario where assets are not coordinated; and finally, confidence in data can yield significant reductions in infrastructural investment costs for key energy assets such as energy storage; we have noted that reduction of uncertainty through data availability (due to digitalization) led to a £3.35 Mreduction of CapEx for a particular case considering energy storage installed at the Port of Tyne. We now continue by showing how we modelled port operational scenarios. We then perform a quantitative analysis of cost and carbon emission savings that can be achieved by intelligent coordination of key processes, as well as savings in the form of deferral of network reinforcement and investment in new assets and technologies due to reduced uncertainty around historical data. We subsequently present our results, key findings, and conclude this article, including some suggestions for future work
Surveillance des systèmes à événements discrets commandés: Conception et implémentation en utilisant l'automate programmable industriel
No full textThis thesis presents an approach to monitoring the controlled discrete events systems. The study is limited to the interruptible faults : intermittent and permanent. To increase the availability of a system, it is crucial to reduce the unnecessary interruptions. For that, the acceptable behavior of these systems is introduced. This behavior presents a tolerance to the intermittent faults. An approach of the construction of monitoring system is presented. We model, firstly, the behavior of the systems by a stopwatch automaton. Secondly, we apply to this automaton a synthesis procedure. This procedure is based on the forward and backward reachability analysis of the stopwatch automaton. A new model called Post- and Pre-initialized stopwatch Petri nets is also presented. This model is used to model the behavior of systems subjected to the interrupting faults. The implementation of our monitoring approach is done by using a Programmable Logic Controller. The monitoring system is translated structurally into a SFC program.Ce mémoire de thèse prèsente une approche pour la surveillance des systèmes à événements discrets commandés. L'étude se restreint aux défauts interruptibles : intermittents et permanents. Le comportement acceptable de ces systèmes est introduit afin d'accroître la disponibilité des systèmes commandés. Ce comportement présente une tolérance aux défauts intermittents. Une démarche de construction du système de surveillance est présentée. Nous modélisons, dans un premier temps, le comportement du système sujet aux défauts interruptibles par un automateà chronomètres. Nous appliquons, dans un deuxième temps, une procédure de synthèse à cet automate. Cette procédure est basée aux opérateurs d'analyse en avant et en arriérer de l'automate. Un nouveau modèle appelé réseaux de Petri à chronomètres post- et Pré-initialisés est également présenté. Ce modèle général du RdP a été utilisé, dans le cadre de ce mémoire, pour modéliser le comportement des systèmes sujets aux défauts interruptibles. L'implémentation de notre méthode de surveillance se fait par un automate programmable industriel. Pour ce faire, le système de surveillance étant sous la forme d'un automate àchronomètres est traduit structurellement en programme SFC
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Réseaux de Petri à chronomètres Post et Préinitialisés
No full textNational audienceUn paradigme de modélisation appelé Réseaux de Petri à chronomètres Post et Préinitialisés SWPN est introduit. Il étend les réseaux de Petri T-temporels en incluant le concept de chronomètre dans sa sémantique. Un mécanisme d'initialisation des chronomètres appelé Post-initialisation est utilisé. Ce mécanisme repose sur l'initialisation du chronomètre après le franchissement de la transition correspondante. Le modèle résultant permet de modéliser de façon naturelle la suspension et la reprise des tâches dans les systèmes temps-réel. Nous présentons d'abord la sémantique formelle de ce modèle sous la forme d'un système de transitions temporisé. Nous proposons ensuite une méthode d'analyse temporelle de ce modèle en le traduisant en automate à chronomètres. La vérification de propriétés temporelles peut alors être effectuée en utilisant l'automate à chronomètres ainsi obtenu. L'avantage de ce modèle est qu'il combine la concision du modèle réseau de Petri et la puissance d'analyse de l'automate à chronomètres
Post and pre-initialized stopwatch Petri nets: Formal semantics and state space computa
No full textInternational audienceA modeling paradigm is introduced which defines an extension of T-Time Petri Nets with the concept of Stopwatch. In this model, stopwatches which are associated with transitions, can be reset either by using classical mechanism in Time Petri Nets or by the firing of the corresponding transitions. The resulting model, which we call Post- and Pre-initialized Stopwatch Petri Nets or SWPN, permits a natural description of so-called preemption-resume behavior. We give the formal semantics of this model as a timed transition system and we position SWPN with regard to other classes of Petri nets destined to model preemptive behavior. We also propose a method for computing the state space of a SWPN as a stopwatch automaton. The method consists of labeling firstly the marking graph of a SWPN as a stopwatch automaton. Then, a forward region- based algorithm is applied to this automaton by using an analyzing tool on linear hybrid system PHAVer in order to compute its reachable states. The obtained automaton is proved to be timed bisimilar to initial SWPN. Thus, the verification of quantitative properties can be conducted thanks to the such obtained automaton
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Design and implementation of a monitiring system using grafcet
No full textInternational audienceA monitoring system based on a stopwatch automaton is proposed to detect the system faults as early as possible. Each location in the automaton corresponds to a system's situation. Its time space delimits exactly the range of the normal behavior in the corresponding system's situation. The monitoring system detects a fault when the time space corresponding to the actual system's situation is violated. The stopwatch automaton provides a formal foundation to model the system's behavior and to synthesize the exactly time space in each location. This paper aims to provide the grafcet monitor that allows to link the design of the monitoring system of a system with its implementation in a programmable logic controller
Monitoring of Timed Discrete Events Systems With Interrupts
No full textInternational audienceA framework is introduced for monitoring the interrupting faults in the timed discrete events systems. We introduce the notion of acceptable behavior of the system subjected to these faults: permanent or intermittent. The acceptable behavior of a system is modeled by a stopwatch automaton. The timed sub-spaces in the locations of the automaton delimit exactly the range of the acceptable behavior. They are synthesized using the techniques of reachability analysis of stopwatch automata in a way to detect the system faults as early as possible
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