Incremental Integer Linear Programming Models for Petri Nets Reachability Problems

http://www.intechopen.com/books/petri_net_theory_and_application

Large enhancement of the thermopower in Nax_xCoO2_2 at high Na doping

Research on the oxide perovskites has uncovered electronic properties that are strikingly enhanced compared with those in conventional metals. Examples are the high critical temperatures of the cuprate superconductors and the colossal magnetoresistance in the manganites. The conducting layered cobaltate $\rm Na_xCoO_2$ displays several interesting electronic phases as $x$ is varied including water-induced superconductivity and an insulating state that is destroyed by field. Initial measurements showed that, in the as-grown composition, $\rm Na_xCoO_2$ displays moderately large thermopower $S$ and conductivity $\sigma$. However, the prospects for thermoelectric cooling applications faded when the figure of merit $Z$ was found to be small at this composition (0.6$<x<$0.7). Here we report that, in the poorly-explored high-doping region $x>$0.75, $S$ undergoes an even steeper enhancement. At the critical doping $x_p\sim$ 0.85, $Z$ (at 80 K) reaches values $\sim$40 times larger than in the as-grown crystals. We discuss prospects for low-temperature thermoelectric applications.Comment: 6 pages, 7 figure

Measuring children’s involvement as an indicator of curriculum effectiveness : a curriculum evaluation of a selected child study centre in Singapore

This paper presents one aspect of a research project evaluating a curriculum model of a selected child study centre in Singapore. An issue of worldwide interest and concern is the &lsquo;quality of learning&rsquo; debate as it relates to early childhood centres. In Singapore, the government is focusing on expansion in child care settings and increases in the amount of funded training. One of the issues surrounding prior-to-school education raises the question of how one measures the quality of teaching and learning, to describe the value of using, funding and promoting early education. The research reported in this study used a quasi experimental research paradigm to assess one aspect of the quality of a curriculum programme in a child study centre in Singapore. Children aged between 18 months and 6 years (N = 81) participated in the research. Using the observation scale of Laevers&rsquo; Child Involvement Scale, the active involvement of children in learning experiences was measured. The findings are presented and discussed

Laughter and humour for personal development: A systematic scoping review of the evidence

The accessibility of laughter and humour make them attractive choices for self-care, and integrative medicine. There is a growing body of literature, but both fields are fragmented and the overall evidence has not been systematically reviewed. The relationship between health and personal development is increasingly recognized. This review scopes the evidence for laughter and humour interventions from the perspective of their potential benefits on personal development. A systematic scoping review used Joanna Briggs guidelines and the Preferred Reporting Items for Systematic Reviews Scoping Review extension (PRISMA-ScR). All-population laughter and humour interventions described in primary and secondary research from 1970, and in English, were searched in Web of Science and PubMed/Medline. Analysis of 240 primary research articles (k), and 11 systematic reviews (K), identified k = 564 discrete articles with studies involving 574,611 participants (n). Twelve large studies (n >15,000) contributed 77% of participants. Classification analysis found more research relating to humour (k = 445, n = 334,996) than laughter (k = 119, n = 239,615) and identified diverse personal development outcomes associated with Biological, Psychological, Social, Environmental, and Behavioural (BPSE-B) factors. This review presents growing evidence for the diverse applications and benefits of laughter and humour. Multiple opportunities for self-care and interventional applications are described. The consideration of personal development outcomes may support tailored applications according to specific needs and objectives. An umbrella Personal Development Theory of laughter and humour, inclusive humour and laughter definitions, and a humour-laughter-affect model are proposed to unify the fields.N/

Extraction of Critical Scenarios in a Railway Level Crossing Control System

Abstract: This paper deals with the safety of the level crossing control system. We propose one way of the safety evaluation witch consist on the extraction of feared scenarios in the Petri net model of the system. We use ESA_PetriNet tool (Extraction Scenarios &amp; Analyzer by Petri Net model) that was developed in the aim of extraction of feared scenarios in computer-controlled systems. These scenarios characterize the sequences of actions leading to dangerous situations. The taking into account of the failures, the temporal constraints and partially the continuous dynamic (by temporal abstraction) of the system makes it possible to respect the order of appearance of the events in the generated scenarios

Modeling Information System Behavior with Dynamic Relations Nets

In this paper we highlight three main qualities for a processing model: processing abstraction, dynamic behavior and graphical representation. We define a model closely related to high-level Petri Nets. Dynamic Relations Nets (DRN) allow the specification of data, processing, events and constraints within a unique graphical representation. Annotations of the net use a set based abstract language. Constraints arise from three levels: from places (related to the notion of abstract type), from markings (we can then express global constraints between places), and from transitions (in order to specify processing as state transformations). The DRN formalism has been successfully applied to a number of case studies. In this paper, we develop the standard `IFIP case , which has been handled with a lot of modeling methods. A DRN specification has a well defined operational semantics. Therefore a DRN can also be viewed as an executable specification of information systems. We briefly introduce a tool designed to operate an application developed with DRNs, namely NetSpec, based on the use of an active database management system. This tool allows an automated code generation (C/SQL) from a DRN specification

Two stages optimization problem: New variant of Bin Packing Problem for decision making

Abstract—In this paper, we present a new multi-criteria assignment problem that groups characteristics from the well known Bin Packing Problem (BPP) and Generalized Assign-ment Problem (GAP). Similarities and differences between these problems are discussed, and a new variant of BPP is presented. The new variant will be called generalized assignment problem with identified first-use bins (GAPIFB). The GAPIFB will be used to supply decision makers with quantitative and qualitative indicators in order to optimize a business process. An algorithm based on the GAP problem model and on GAPIFB is proposed. I

Integrating a business process analysis and optimization step using BPMN model in a general process design and development approach (application to a paperless mail flow process)

Cette thèse a été réalisée dans le cadre du projet Gestion et Optimisation de la Chaîne Documentaire , projet labellisé par le Pôle de compétitivité des Industries du Commerce. Le projet a pour but de concevoir et de développer un nouveau workflow et un outil d aide à la décision. Ce système doit être capable de gérer et d optimiser le flux complet dématérialisé de contrats reçus à COFIDIS.Nous présentons d abord le framework retenu dans le cadre du projet pour modéliser et implémenter le workflow. En phase de conception BPMN a été choisi. Pour la partie développement, l utilisation de BPEL a été préconisée pour implémenter et exécuter l'application finale (services web).Cependant la flexibilité offerte par BPMN peut conduire à des propriétés indésirables du processus telles que blocage et inaccessibilité. De plus, BPMN a été conçu pour fournir des modèles Orientés Process. Les données ou les ressources y sont donc peu représentées. En conséquence, l'analyse de performance sur un modèle BPMN est quasi inexistante.Afin de surmonter ces problèmes nous proposons d insérer dans le framework deux nouvelles phases. Ces deux phases sont appliquées au modèle BPMN. La première est une phase de vérification et de validation et la deuxième une phase d'optimisation. Ces deux phases sont réalisées en transformant le modèle BPMN vers un langage formel. Notre choix dans ce travail a été d'utiliser les réseaux de Petri. Ce qui nous a permis de vérifier et de valider de bonnes propriétés du process. Quant à l optimisation, nous avons défini une nouvelle variante du problème d affectation (bin packing problem) et proposé une résolution à intégrer dans le processus d aide à la décisionThis thesis has been realized as a part of the project GOCD (French acronym for Management and optimization of document life cycle) and within the context of the French competitive cluster PICOM. The project aims to design and develop a new paperless workflow system and decision making tool to replace the current paper based system. The new workflow system must manage and optimize received credit demands at COFIDIS.The first part of this thesis presents and discusses a framework to model and implement workflow systems. The proposed framework allows more flexibility in workflow reengineering process and operational analysis for different business process. The proposed framework uses the most recent and promising language to model and execute workflow the Business Process Modeling Notation (BPMN) and Business Process Execution Language (BPEL).The flexibility offered by BPMN can also lead to undesirable properties for business process such as deadlocks and unreachablity. More, BPMN notation was designed to model business process, and little consideration was concentrated to represent data and resources. As a result, carrying out performance analysis on a BPMN model is also limited.To overcome these problems, we propose two additional phases in the reengineering process. They are applied to the target BPMN model. The first phase is verification and validation and the second one is optimization. These two phases are realized by transforming the BPMN model to a formal language, Petri nets. As for optimization, a new variant of bin packing problem has been defined. And we propose to integrate its resolution in a decision making toolVILLENEUVE D'ASCQ-ECLI (590092307) / SudocSudocFranceF

State Observer for DES Under Partial Observation with Time Petri Nets

International audienceThis paper deals with a state observation approach for Discrete Event Systems with a known behavior. The system behavior is modeled using a Time Petri Net model. The proposed approach exploits temporal constraints to assess the system state and therefore detect and determine faults given partial observability of events. The goal here is to track the system state and to identify the event scenarios which occur on the system. Our approach uses the class graph of the Time Petri Net which models the complete system behavior to develop a state observer which is a base to perform online fault detection and diagnosing

Techniques d'abstraction pour l'analyse et la synthèse de réseaux de Petri

Le croisement de concepts issus de la logique, de la recherche opérationnelle et de ï'automatique discrète nous .permet de nous intéresser au problème de l'explosion combinatoire sous des angles d'attaque nouveaux, pour proposer finalement un ensemble de techniques d'abstraction pour l'analyse et la synthèse de réseaux de Petri. Pour l'analyse, nous proposons une abstraction du comportement des RdPs. Le résultat principal concerne la définition d'un modèle incrémentai permettant de capturer le comportement du RdP étudié. Ce modèle permet la formulation de propriétés dites positives dont l'expressivité s'étend aux problématiques d'accessibilité et de sûreté. Nous le traduisons ensuite en un problème d'optimisation combinatoire, et proposons plusieurs modèles opérationnels et techniques complémentaires permettant d'améliorer les performances pratiques de résolution. Dans le cadre de l'étude des RdPs bornés, nous contribuons également à la défmition formelle des paramètres de profondeur séquentielle et intrinsèque, qui permettent de garantir les propriétés de décidabilité de nos algoritlnnes. Pour la synthèse, nous développons une abstraction de la structure des RdPs. Nous utilisons cette abstraction pour présenter une approche de conception incrémentale originale fondée sur la notion d'exigences de fonctionnement. Cette démarche exploratoire consiste à intégrer dans une même méthodologie des techniques de spécification formelle et de vérification. Les exigences sont traduites en termes de contraintes sur les éléments d'une structure appelée RdP1 partieL Des outils de résolution de contraintes permettent ensuite de générer les réseaux satisfaisant les exigences de départ.LILLE1-BU (590092102) / SudocVILLENEUVE D'ASCQ-ECLI (590092307) / SudocCACHAN-ENS (940162301) / SudocSudocFranceF