Second-Order Conformally Equivariant Quantization in Dimension 1|2

This paper is the next step of an ambitious program to develop conformally equivariant quantization on supermanifolds. This problem was considered so far in (super)dimensions 1 and 1|1. We will show that the case of several odd variables is much more difficult. We consider the supercircle $S^{1|2}$ equipped with the standard contact structure. The conformal Lie superalgebra $\mathcal{K}(2)$ of contact vector fields on $S^{1|2}$ contains the Lie superalgebra osp(2|2). We study the spaces of linear differential operators on the spaces of weighted densities as modules over osp(2|2). We prove that, in the non-resonant case, the spaces of second order differential operators are isomorphic to the corresponding spaces of symbols as osp(2|2)-modules. We also prove that the conformal equivariant quantization map is unique and calculate its explicit formula

Conformally equivariant second-order differential operators in dimension 1|2: Quantization and symbol calculus

11This paper is the next step of an ambitious program to develop conformally equivariant quantization on supermanifolds. This problem was considered so far in (super)dimensions 1 and 1|1. We will show that the case of several odd variables is much more difficult. We consider the supercircle $S^{1|2}$ equipped with the standard contact structure. The conformal Lie superalgebra K(2) of contact vector fields on $S^{1|2}$ contains the Lie superalgebra osp(2|2). We study the spaces of linear differential operators on the spaces of weighted densities as modules over osp(2|2). We prove that, in the non-resonant case, the spaces of second order differential operators are isomorphic to the corresponding spaces of symbols as osp(2|2)-modules. We also prove that the conformal equivariant quantization map is unique and calculate its explicit formula

FATMAS: a methodology to design fault-tolerant multi-agent systems

Un système multi-agent (SMA) est un système dans lequel plusieurs agents opèrent et interagissent. Chaque agent a la responsabilité d’exécuter des tâches. Cependant, chaque agent, pour diverses raisons, peut rencontrer des problèmes pendant l’exécution de ses tâches ; ce qui peut induire un disfonctionnement du SMA. Cependant, le SMA doit être en mesure de détecter les sources de problèms (d’erreurs) afin de les contrôler et ainsi continuer son exécution correctement. Un tel SMA est appelé un SMA tolérant aux fautes. Il existe deux types de sources d’erreurs pour un agent : les erreurs causées par son environnment et les erreurs dûes à sa programmation. Dans la littérature, il existe plusieurs techniques qui traitent des erreurs de programmation au niveau des agents. Cependant, ces techniques ne traitent pas des erreurs causées par l’environnement de l’agent. Tout d’abord, nous distinguons entre l’environnment d’un agent et l’environnement du SMA. L’environnement d’un agent représente toutes les composantes matérielles ou logicielles que l’agent ne peut contrôler mais avec lesquelles il interagit. Cependant, l’environnment du SMA représente toutes les composantes que le système ne contrôle pas mais avec lesquelles il interagit. Ainsi, le SMA peut contrôler certaines des composantes avec lesquelles un agent interagit. Ainsi, une composante peut appartenir à l’environnement d’un agent et ne pas appartenir à l’environnement du système. Dans ce travail, nous présentons une méthodologie de conception de SMA tolérants aux fautes, nommée FATMAS, qui permet au concepteur du SMA de détecter et de corriger, si possible, les erreurs causées par les environnements des agents. Cette méthodologie permettra ainsi de délimiter la frontière du SMA de son environnement avec lequel il interagit. La frontière du SMA est déterminée par les différentes composantes (matérielles ou logicielles) que le système contrôle. Ainsi, le SMA, à l’intérieur de sa frontière, peut corriger les erreurs provenant de ses composantes. Cependant, le SMA n’a aucun contrôle sur toutes les composantes opérant dans son environnement. La méthodologie, que nous proposons, doit couvrir les trois premières phases d’un développement logiciel qui sont l’analyse, la conception et l’implémentation tout en intégrant, dans son processus de développement, une technique permettant au concepteur du système de délimiter la frontière du SMA et ainsi détecter les sources d’erreurs et les contrôler afin que le système multi-agent soit tolérant aux fautes (SMATF). Cependant, les méthodologies de conception de SMA, référencées dans la littérature, n’intègrent pas une telle technique. FATMAS offre au concepteur du SMATF quatre modèles pour décrire et développer le SMA ainsi qu’une technique de réorganisation du système qui lui permet de détecter et de contrôler ses sources d’erreurs, et ainsi définir la frontière du SMA. Chaque modèle est associé à un micro processus qui guide le concepteur lors du développement du modèle. FATMAS offre aussi un macro-processus, qui définit le cycle de développement de la méthodologie. FATMAS se base sur un développement itératif pour identifier et déterminer les tâches à ajouter au système afin de contrôler des sources d’erreurs. À chaque itération, le concepteur évalue, selon une fonction de coût/bénéfice s’il est opportun d’ajouter de nouvelles tâches de contrôle au système. Le premier modèle est le modèle de tâches-environnement. Il est développé lors de la phase d’analyse. Il identifie les différentes tâches que les agents doivent exécuter, leurs préconditions et leurs ressources. Ce modèle permet d’identifier différentes sources de problèmes qui peuvent causer un disfonctionnement du système. Le deuxième modèle est le modèle d’agents. Il est développé lors de la phase de conception. Il décrit les agents, leurs relations, et spécifie pour chaque agent les ressources auxquelles il a le droit d’accéder. Chaque agent exécutera un ensemble de tâches identifiées dans le modèle de tâches-environnement. Le troisième modèle est le modèle d’interaction d’agents. Il est développé lors de la phase de conception. Il décrit les échanges de messages entre les agents. Le quatrième modèle est le modèle d’implémentation. Il est développé lors de la phase d’implémentation. Il décrit l’infrastructure matérielle sur laquelle le SMA va opérer ainsi que l’environnement de développement du SMA. La méthodologie inclut aussi une technique de réorganisation. Cette technique permet de délimiter la frontière du SMA et contrôler, si possible, ses sources d’erreurs. Cette technique doit intégrer trois techniques nécessaires à la conception d’un système tolérant aux fautes : une technique de prévention d’erreurs, une technique de recouvrement d’erreurs, et une technique de tolérance aux fautes. La technique de prévention d’erreurs permet de délimiter la frontière du SMA. La technique de recouvrement d’erreurs permet de proposer une architecture du SMA pour détecter les erreurs. La technique de tolérance aux fautes permet de définir une procédure de réplication d’agents et de tâches dans le SMA pour que le SMA soit tolérant aux fautes. Cette dernière technique, à l’inverse des techniques de tolérance aux fautes existantes, réplique les tâches et les agents et non seulement les agents. Elle permet ainsi de réduire la complexité du système en diminuant le nombre d’agents à répliquer. Résumé iv De même, un agent peut ne pas être en erreur mais la composante matérielle sur laquelle il est exécuté peut ne plus être fonctionnelle. Ce qui constitue une source d’erreurs pour le SMA. Il faudrait alors que le SMA continue à s’exécuter correctement malgrè le disfonctionnement d’une composante. FATMAS fournit alors un support au concepteur du système pour tenir compte de ce type d’erreurs soit en contrôlant les composantes matérielles, soit en proposant une distribution possible des agents sur les composantes matérielles disponibles pour que le disfonctionnement d’une composante matérielle n’affecte pas le fonctionnement du SMA. FATMAS permet d’identifier des sources d’erreurs lors de la phase de conception du système. Cependant, elle ne traite pas des sources d’erreurs de programmation. Ainsi, la technique de réorganization proposée dans ce travail sera validée par rapport aux sources d’erreurs identifiées lors de la phase de conception et provenant de la frontière du SMA. Nous démontrerons formellement que, si une erreur provient d’une composante que le SMA contrôle, le SMA devrait être opérationnel. Cependant, FATMAS ne certifie pas que le futur système sera toujours opérationnel car elle ne traîte pas des erreurs de programmation ou des erreurs causées par son environnement.A multi-agent system (MAS) consists of several agents interacting together. In a MAS, each agent performs several tasks. However, each agent is prone to individual failures so that it can no longer perform its tasks. This can lead the MAS to a failure. Ideally, the MAS should be able to identify the possible sources of failures and try to overcome them in order to continue operating correctly ; we say that it should be fault-tolerant. There are two kinds of sources of failures to an agent : errors originating from the environment with which the agents interacts, and programming exceptions. There are several works on fault-tolerant systems which deals with programming exceptions. However, these techniques does not allow the MAS to identify errors originating from an agent’s environment. In this thesis, we propose a design methodology, called FATMAS, which allows a MAS designer to identify errors originating from agents’ environments. Doing so, the designer can determine the sources of failures it could be able to control and those it could not. Hence, it can determine the errors it can prevent and those it cannot. Consequently, this allows the designer to determine the system’s boundary from its environment. The system boundary is the area within which the decision-taking process of the MAS has power to make things happen, or prevent them from happening.We distinguish between the system’s environment and an agent’s environment. An agent’s environment is characterized by the components (hardware or software) that the agent does not control. However, the system may control some of the agent’s environment components. Consequently, some of the agent’s environment components may not be a part of the system’s environment. The development of a fault-tolerant MAS (FTMAS) requires the use of a methodology to design FTMAS and of a reorganization technique that will allow the MAS designer to identify and control, if possible, different sources of system failure. However, current MAS design methodologies do not integrate such a technique. FATMAS provides four models used to design and implement the target system and a reorganization technique to assist the designer in identifying and controlling different sources of system’s failures. FATMAS also provides a macro process which covers the entire life cycle of the system development as well as several micro processes that guide the designer when developing each model. The macro-process is based on an iterative approach based on a cost/benefit evaluation to help the designer to decide whether to go from one iteration to another. The methodology has three phases : analysis, design, and implementation. The analysis phase develops the task-environment model. This model identifies the different tasks the agents will perform, their resources, and their preconditions. It identifies several possible sources of system failures. The design phase develops the agent model and the agent interaction model. The agent model describes the agents and their resources. Each agent performs several tasks identified in the task-environment model. The agent interaction model describes the messages exchange between agents. The implementation phase develops the implementation model, and allows an automatic code generation of Java agents. The implementation model describes the infrastructure upon which the MAS will operate and the development environment to be used when developing the MAS. The reorganization technique includes three techniques required to design a fault-tolerant system : a fault-prevention technique, a fault-recovery technique, and a fault-tolerance technique. The fault-prevention technique assists the designer in delimiting the system’s boundary. The fault-recovery technique proposes a MAS architecture allowing it to detect failures. The fault-tolerance technique is based on agent and task redundancy. Contrary to existing fault-tolerance techniques, this technique replicates tasks and agents and not only agents. Thus, it minimizes the system complexity by minimizing the number of agents operating in the system. Furthermore, FATMAS helps the designer to deal with possible physical component failures, on which the MAS will operate. It proposes a way to either control these components or to distribute the agents on these components in such a way that if a component is in failure, then the MAS could continue operating properly. The FATMAS methodology presented in this dissertation assists a designer, in its development process, to build fault-tolerant systems. It has the following main contributions : 1. it allows to identify different sources of system failure ; 2. it proposes to introduce new tasks in a MAS to control the identified sources of failures ; 3. it proposes a mechanism which automatically determines which tasks (agents) should be replicated and in which other agents ; 4. it reduces the system complexity by minimizing the replication of agents ; Abstract vii 5. it proposes a MAS reorganization technique which is embedded within the designed MAS and assists the designer to determine the system’s boundary. It proposes a MAS architecture to detect and recover from failures originating from the system boundary. Moreover, it proposes a way to distribute agents on the physical components so that the MAS could continue operating properly in case of a component failure. This could make the MAS more robust to fault prone environments. FATMAS alows to determine different sources of failures of a MAS. The MAS controls the sources of failures situated in its boundary. It does not control the sources of failures situated in its environments. Consequently, the reorganization technique proposed in this dissertation will be proven valid only in the case where the sources of failures are controlled by the MAS. However, it cannot be proven that the future system is fault-tolerant since faults originating from the environment or from coding are not dealt with

Projectively Equivariant Quantization and Symbol calculus in dimension 1|2

The spaces of higher-order differential operators (in Dimension 1|2), which are modules over the stringy Lie superalgebra K(2), are isomorphic to the corresponding spaces of symbols as orthosymplectic modules in non resonant cases. Such an osp (2|2)-equivariant quantization, which has been given in second-order differential operators case, keeps existing and unique. We calculate its explicit formula that provides extension in particular order cases.Comment:

Taxonomy and antimicrobial activities of a new Streptomyces sp. TN17 isolated in the soil from an oasis in Tunis

An actinomycete strain referred to as TN17 was screened for its antimicrobial activities. The taxonomic status of this strain was established. The organism was found to have morphological and chemotaxonomic characteristics typical of Streptomycetes. Based on the 16S rRNA nucleotide sequences, Streptomyces sp. TN17 was found to have a relationship with Streptomyces lilaceus, Streptomyces gobitricini and Streptomyces lavendofoliae. Combined analysis of the 16 S rRNA gene sequence (FN687757), phylogenetic analysis, fatty acids profile and physiological tests indicated that there are genotypic and phenotypic differences between TN17 and neighboring Streptomyces species’ neighbors. Therefore, TN17 is a novel species: Streptomyces sp. TN17 (=DSM 42020T=CTM50229T). A cultured extract of this strain inhibits the growth of several Gram positive and Gram negative bacteria and fungi

Winning the SDG battle in cities : how an integrated information ecosystem can contribute to the achievement of the 2030 sustainable development goals

In 2015, the United Nations adopted an ambitious development agenda composed of 17 sustainable development goals (SDGs), which are to be reached by 2030. Beyond SDG 11 concerning the development of sustainable cities, many of the SDGs target activities falling within the responsibility of local governments. Thus, cities will play a leading role in the achievement of these goals, and we argue that the information systems (IS) community must be an active partner in these efforts. This paper aims to contribute to the achievement of the SDGs by developing a conceptual model to explain the role of IS in building smart sustainable cities and providing a framework of action for IS researchers and city managers. To this end, we conduct grounded theory studies of two green IS used by an internationally recognized smart city to manage water quality and green space. Based on these findings, we articulate a model explaining how an integrated information ecosystem enables the interactions between three interrelated spheres – administrative, political and sustainability – to support the development of smart sustainable cities. Moving from theory to practice, we use two real‐world scenarios to demonstrate the applicability of the model. Finally, we define an action framework outlining key actions for cities and suggest corresponding questions for future research. Beyond a simple call‐to‐action, this work provides a much‐needed foundation for future research and practice leading to a sustainable future for all

The Contribution of Internal Communication to the Social Performance of the Company: Case of Moroccan SME

This research focuses on the contribution of internal communication, through its various antecedents, on social performance by integrating human skills and entrepreneurial motivation in Morocco. Given the development of ICT (Information and Communication Technologies), individual and collective behaviors at work have changed, so we faced difficult communication. The application of human resources management is more requested so that it promotes the acquisition of knowledge, their exploitation, know-how, and creativity everywhere to companies, public and private organizations, indeed this application improves the working conditions and the acquisition of global performance. We have carried out a state of the art on theoretical framework, through which we seek to highlight the contributions of internal communication within the organization on the managerial level. This literature review has allowed us to establish eight hypotheses concerning the delimitation of the concept of internal communication, to determine its purposes and consequently to identify the dimensions of said purposes; with qualitative methodology through its four contributions to the organization, in this case, the commitment, satisfaction, motivation and individual performance that represent a management lever capable of developing a capacity and a performing competence.   Keywords: Internal Communication; Organizational Commitment; Corporate Social Performance; Know-How. JEL Classification: O1. O15. O35 Paper type: Empirical research  This research focuses on the contribution of internal communication, through its various antecedents, on social performance by integrating human skills and entrepreneurial motivation in Morocco. Given the development of ICT (Information and Communication Technologies), individual and collective behaviors at work have changed, so we faced difficult communication. The application of human resources management is more requested so that it promotes the acquisition of knowledge, their exploitation, know-how, and creativity everywhere to companies, public and private organizations, indeed this application improves the working conditions and the acquisition of global performance. We have carried out a state of the art on theoretical framework, through which we seek to highlight the contributions of internal communication within the organization on the managerial level. This literature review has allowed us to establish eight hypotheses concerning the delimitation of the concept of internal communication, to determine its purposes and consequently to identify the dimensions of said purposes; with qualitative methodology through its four contributions to the organization, in this case, the commitment, satisfaction, motivation and individual performance that represent a management lever capable of developing a capacity and a performing competence.   Keywords: Internal Communication; Organizational Commitment; Corporate Social Performance; Know-How. JEL Classification: O1. O15. O35 Paper type: Empirical research &nbsp

Produktionsprogrammplanung unter Einbeziehung von Preis-Absatz-Funktionen und Lernkurveneffekten

Eine der Managementaufgaben besteht im Treffen von Entscheidungen, wobei im Sinne der normativen Entscheidungstheorie ein reales Entscheidungsproblem in Form eines Entscheidungsmodells abzubilden und mit geeigneten Verfahren zu lösen ist. Die Modellierung betriebswirtschaftlicher Entscheidungsprobleme erfolgt im operativen und taktischen Bereich vielfach unter der Annahme linearer Kosten- und Erlösfunktionen. Dieser Sachverhalt ergibt sich in erster Linie aus den verwendeten Systemen der internen Unternehmensrechnung. So werden entscheidungsrelevante Kosten und Erlöse üblicherweise mit der Grenzkosten- und Grenzerlösrechnung geplant, wobei gemäß den Prämissen dieser Systeme alle Einflussgrößen bis auf die Produktions- bzw. Absatzmengen als konstant unterstellt werden.1 Ein weiterer Grund für die Verwendung linearer Funktionsverläufe besteht darin, dass die Einbeziehung nichtlinearer Zusammenhänge vielfach zu Modellstrukturen führt, deren Lösbarkeit bei größeren Modelldimensionen als problematisch anzusehen ist. Allerdings kann die Beschränkung auf lineare Erlös- und Kostenstrukturen zu einer zu vereinfachenden Modellierung der realen Entscheidungssituation führen, da die Absatzpreise und Stückkosten oft in nichtlinearen Zusammenhängen zu den Absatz- und Produktionsmengen stehen. Exemplarisch lassen sich Preis-Absatz-Funktionen, Lernkurveneffekte, sprungfixe Kosten- bzw. Erlösverläufe und Variablenprodukte nennen. In diesem Sinn besteht das erste Ziel dieser Arbeit in der Erarbeitung von Ansätzen zur Einbeziehung nichtlinearer Zusammenhänge in betriebswirtschaftliche Entscheidungsprobleme

EXAMINING THE INFLUENCE OF EXTERNAL STAKEHOLDERS ON IT GOVERNANCE: PERCEPTIONS OF IT EXECUTIVES

Information Technology (IT) governance decisions usually involve several stakeholders with divergent claims. Past research on IT governance focused on internal stakeholders\u27 responsibilities and roles in IT governance decisions. However, we don’t know much about external stakeholders’ place in IT governance. Based on stakeholder theory, a qualitative research approach is adopted to determine the importance of different external stakeholders in IT governance by examining how they are prioritized in this context. Results suggested that external stakeholders’ prioritization in IT governance context as perceived by IT executives vary according to IT decision domains. Moreover external stakeholders’ influence over IT decision domains may be direct or indirect depending on their active role in IT activities or on their relationship with the organization as a whole. Implications of results are discussed