309 research outputs found

    A Survey on Service Composition Middleware in Pervasive Environments

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    The development of pervasive computing has put the light on a challenging problem: how to dynamically compose services in heterogeneous and highly changing environments? We propose a survey that defines the service composition as a sequence of four steps: the translation, the generation, the evaluation, and finally the execution. With this powerful and simple model we describe the major service composition middleware. Then, a classification of these service composition middleware according to pervasive requirements - interoperability, discoverability, adaptability, context awareness, QoS management, security, spontaneous management, and autonomous management - is given. The classification highlights what has been done and what remains to do to develop the service composition in pervasive environments

    From Network to Web dimension in supply chain management

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    Cette thèse soutient que la dimension réseau, étant actuellement la portée du domaine de la gestion de chaîne logistique, contraint l’avancement de ce domaine et restreint des innovations conceptuelles et fondamentales capables d’adresser les grands défis économiques, environnementaux et sociaux. Les concepts de chaîne et de réseau ne reflètent pas la complexité des flux physiques, informationnels et financiers générés par les interactions qui ont lieu dans des réseaux interconnectés. Ces concepts n’offrent pas les fondations théoriques pour supporter des interventions allant au-delà d’un seul réseau et laissent échapper des opportunités nécessitant une vision multi-réseau. Ainsi, la dimension “web”, celle des réseaux de réseaux, est proposée comme une extension de la dimension réseau. Cette extension peut être vue comme l’étape naturelle suivante dans la progression qui a commencé par le niveau de gestion des opérations internes, est passée au niveau de la chaîne logistique et se trouve actuellement au niveau du réseau logistique. Après l’investigation théorique des raisons et de la façon d’intégrer la dimension web dans le domaine de la gestion de la chaîne logistique, la thèse étudie des implications importantes de cette intégration sur la collaboration inter-organisationnelle et le processus de prise de décision dans des environnements de webs logistiques. Elle démontre, en exploitant l’exemple des réseaux interconnectés ouverts, des potentialités inimaginables sans une vision web. Une méthodologie de conception d’un modèle de simulation permettant l’évaluation et la comparaison des webs ouverts par rapport aux webs existants est proposée. Puisque l’aide à la décision est une composante importante de la gestion de la chaîne logistique, la thèse contribue à déterminer les besoins des gestionnaires et à identifier les lignes directrices de la conception des outils d’aide à la décision offrant le support adéquat pour faire face aux défis et à la complexité des webs logistiques. Ces lignes directrices ont été compilées dans un cadre de conception des logiciels d’aide à la décision supportant la dimension web. Ce cadre est exploité pour développer quatre applications logicielles offrant aux praticiens et aux chercheurs des outils nécessaires pour étudier, analyser et démêler la complexité des webs logistiques.This thesis argues that the network dimension as the current scope of supply chain management is confining the evolution of this field and restricting the conceptual and fundamental innovations required for addressing the major challenges imposed by the evolution of markets and the increased intricacies of business relationships. The concepts of chain and network are limitative when attempting to represent the complexity of physical, informational and financial flows resulting from the interactions occurring in overlapping networks. They lack the theoretical foundations necessary to explain and encompass initiatives that go beyond a single chain or network. They also lead to overlook substantial opportunities that require beyond a network vision. Therefore, the “web” dimension, as networks of networks, is proposed as an extension to the network dimension in supply chain management. This new scope is the natural next step in the progression from the internal operations management level to the supply chain level and then to the supply network level. After a theoretical investigation of why and how the web dimension should be integrated into the supply chain management field, the thesis studies and discusses important implications of this integration on inter-organisational collaboration and of the decision-making processes in the logistic web environments. It demonstrates through the example of open interconnected logistic webs some of the potentials that cannot be imagined without a web vision. A methodology for designing a simulation model to assess the impact of such open webs versus existing webs is proposed. Since decision support is a key element in supply chain management, the thesis contributes to determine the needs of supply chain managers and identify the important axes for designing decision support systems that provide adequate assistance in dealing with the challenges and complexity presented by logistic web environments. The identified elements result in the establishment of a foundation for designing software solutions required to handle the challenges revealed by the web dimension. This conceptual framework is applied to the prototyping of four applications that have the potential of providing practitioners and researchers with the appropriate understanding and necessary tools to deal with the complexity of logistics webs

    Impact of information exchange on supply chain strategies

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    Due to globalisation and the competition faced from Asian countries, there is an emergent need to investigate how to extend the limited capabilities of developing countries in order to survive in the market as well as reach global market. Developing countries play an important role as OEM units to provide global markets with under-brand names. Many difficulties face the industrial zones in these countries in their attempt to reach this target and these prevent them from providing their own brands. For example, many sectors in Egyptian industry are outperformed by Chinese competition and have even lost their domestic market share. Textiles are one of the most affected industries as a result of this competition. The risk of Egyptian fabrics vanishing from global markets is indicated by a huge reduction in export rate after the quota phase-out. Egyptian textile producers rely on global agreements to reach global markets. The period after the Multi-Fibre agreement shows an obvious drop in exportation rates till the Qualified Industrial Zones (QIZ) agreement was issued. Can the same scenario occur after QIZ quota phase-out? What should Egyptian fabric manufacturer do? Since the situation is alarming and may result in exporting the high quality Egyptian cotton to global markets instead of to its domestic manufacturers, the flood of Chinese fabrics in Egyptian Markets requires that the question “how to survive and compete with low-cost Chinese fabrics?” be investigated. The aim of the research was to investigate the deficiencies experienced by Egyptian firms trying to reach global markets and maintain their domestic market share. The research conducted an exploratory-explanatory empirical study to identify the major issues facing textile fabricators in Egyptian industrial zones. Case studies and a survey outcome were matched to provide validated empirical findings. An Interpretive Structuring Modelling approach was used to indicate the stages of supply chain deficiencies based on the case study findings. The major issues causing supply chain deficiencies are defined from the case study analysis and validated using the survey approach. The outcome of the empirical study indicates that supply chain design, integration and IT infrastructure are considered as major issues that lead to the existing deficiencies of the textile industry supply chain in Egypt despite the low level assigned to their importance. At the same time, production and procurement issues are considered as dependant on poor supply chain design, IT infrastructure and unreliable forecasting despite the high level assigned to their importance. A stage-based model for supply chain deficiencies in the Egyptian textile sector was highlighted in this study to indicate dependency and driving power among internal deficiencies. A framework, indicates supply chain deficiencies and their leading factors in Egypt, was concluded from this study. The study points out a number of external issues related to the surrounding environment and the government’s role in contributing to the aggravation of the existing deficiencies. The research uses simulation techniques to test the proposed solution that might provide better supply chain performance. A System Dynamic approach is used to model a case study of the investigated industry. Different scenarios of fulfilling local and international orders have been tested. These scenarios are represented in: expansion of production capacity, reduction of inventory levels or reduction of procurement time. Since addressing the internal deficiency, which empirical study respondents’ pointed out as being the most important one, could not provide an adaquate solution for the existing deficiencies, supply chain re-structuring to represent a collaborative pattern between partners was, therefore, tested and proved to have a great effect on supply chain performance. A collaborative pattern among supply chain partners indicated its positive impact on supply chain performance. The simulation experiments prove that the individual decisions of supply chain partners cannot bring about improvement to supply chain cost and responsiveness. The negative impact of an unreliable logistic system on supply chain performance was confirmed through the simulation experiments. The study provides the managerial levels in textile organisations with a solid causal basis for the supply chain deficiencies in the Egyptian textile sector. The outcome of the work can be employed by governmental authorities to address such difficulties and accelerate the growth of this sector globally. The thesis provides the fundamentals for investigating deficiencies in developing countries that might be extended by other researchers to investigate other defective sectors in Egypt and other developing countries

    Integrated Real-Virtuality System and Environments for Advanced Control System Developers and Machines Builders

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    The pace of technological change is increasing and sophisticated customer driven markets are forcing rapid machine evolution, increasing complexity and quality, and faster response. To survive and thrive in these markets, machine builders/suppliers require absolute customer and market orientation, focusing on .. rapid provision of solutions rather than products. Their production systems will need to accommodate unpredictable changes while maintaining financial and operational efficiency with short lead and delivery times. Real-Virtuality (R-V) systems are an innovative environment to address these requirements by facilitating enhanced support in machine system design utilising integrated real-virtual environments centred on concurrent machine system development and realization. This environment supports not only machine system design but also the development of the' control system at the same time. Utilising the Real-Virtual Mapping Environment (RVMI;:), 3-D simulation machine models can perform actual machine operations in real-time when coupled with the real machine controller. This provides a more understandable, reliable and transparent machine function and performance. The research study explores different types of controller verification methods and proposes a new method which employs the use of a control signal emulator. The research study has fomulated a novel technique for emulating quadrature encoder signals to provide virtual closed loop control of servomotors. The deployment of a control signal emulator technique makes the system unique and removes its dependency on specific hardware. Enabling the real-time data from the signal emulation environment eases the task of realising a real-time machine simulator. To evaluate the proposed architecture, three case studies were performed. The results have shown that it is possible to create verified and validated machine control programs with no modification needed when applied to the real machine. The migration from the virtual to the real world is totally seamless. The result from the ????study show that the virtual machine is able to operate and respond as a real machine in real-time. This opens up the unexplored potential of integrated 3-D virtual technology. The real-time 3-D simulation virtual machine will enable commissioning and training to be conducted '!-t an earlier stage in the design process (without having to wait for the real machine to be built). Furthermore, various test scenarios can also be developed and tested on the system which helps to provide a better lofriderstanding of the machine behaviours and responses. This research study has made an original contribution in the field of machine system development. It has contributed a novel approach of using emulated control signals to provide machine control programmers with a platform to test their application programs at machine level which involves both discrete digital signals and continuous signals. The real-time virtual environment extends the application domain for the use of simulation. The architecture proposed is generic; to be exact it is not constrained to a specific industrial control system or to a specific simulation vendor

    Supply Chain

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    Traditionally supply chain management has meant factories, assembly lines, warehouses, transportation vehicles, and time sheets. Modern supply chain management is a highly complex, multidimensional problem set with virtually endless number of variables for optimization. An Internet enabled supply chain may have just-in-time delivery, precise inventory visibility, and up-to-the-minute distribution-tracking capabilities. Technology advances have enabled supply chains to become strategic weapons that can help avoid disasters, lower costs, and make money. From internal enterprise processes to external business transactions with suppliers, transporters, channels and end-users marks the wide range of challenges researchers have to handle. The aim of this book is at revealing and illustrating this diversity in terms of scientific and theoretical fundamentals, prevailing concepts as well as current practical applications

    Towards Data Sharing across Decentralized and Federated IoT Data Analytics Platforms

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    In the past decade the Internet-of-Things concept has overwhelmingly entered all of the fields where data are produced and processed, thus, resulting in a plethora of IoT platforms, typically cloud-based, that centralize data and services management. In this scenario, the development of IoT services in domains such as smart cities, smart industry, e-health, automotive, are possible only for the owner of the IoT deployments or for ad-hoc business one-to-one collaboration agreements. The realization of "smarter" IoT services or even services that are not viable today envisions a complete data sharing with the usage of multiple data sources from multiple parties and the interconnection with other IoT services. In this context, this work studies several aspects of data sharing focusing on Internet-of-Things. We work towards the hyperconnection of IoT services to analyze data that goes beyond the boundaries of a single IoT system. This thesis presents a data analytics platform that: i) treats data analytics processes as services and decouples their management from the data analytics development; ii) decentralizes the data management and the execution of data analytics services between fog, edge and cloud; iii) federates peers of data analytics platforms managed by multiple parties allowing the design to scale into federation of federations; iv) encompasses intelligent handling of security and data usage control across the federation of decentralized platforms instances to reduce data and service management complexity. The proposed solution is experimentally evaluated in terms of performances and validated against use cases. Further, this work adopts and extends available standards and open sources, after an analysis of their capabilities, fostering an easier acceptance of the proposed framework. We also report efforts to initiate an IoT services ecosystem among 27 cities in Europe and Korea based on a novel methodology. We believe that this thesis open a viable path towards a hyperconnection of IoT data and services, minimizing the human effort to manage it, but leaving the full control of the data and service management to the users' will

    Review of IT Service Management Tools Currently in Use in Finland : ITIL®, Implementation and Functionality

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    This thesis was carried out for itSMF Finland, an IT Service Management (ITSM) cooperation forum. The itSMF Finland is a non-profit organization dedicated to the development and promotion of best practice ITSM. ITSM is about providing a framework to structure IT-related activities and the interaction of IT technical personnel with business customers and users. ITSM practices have existed for some time already, but the technology to support it has only recently become more advanced and comprehensive. The purpose of this thesis was to investigate the requirements for ITSM tools and to create a “snapshot” of the current situation of the ITSM tool market in Finland. IT Infrastructure Library (ITIL®) was chosen as a framework for this thesis, which is considered as de-facto best practice model in ITSM. This research investigates the requirements stated in ITIL® for the ITSM technologies. Nine tools were chosen for interviews. The object of the interviews was to gain information about what functionalities are included in the tools, how the vendor supports the customer in the implementation project, and what the customer experiences are regarding the implementation and use of the tool. These results were then compared to the ITIL® framework. ITIL® recommends the tools to be utilized in the organization to provide data for analysis and improvement of the service provision and also to support the service lifecycle. All tools in this study were ITSM suites that have functionalities to support the service lifecycle widely. Based on the interviews the study shows that the tools are important for the organizations, but are not as widely used as they could be. The implementation projects varied greatly, but were relatively successful in all cases. All in all, the tools were considered beneficial for the organizations in all cases. This thesis provides important key-points to be kept in mind when selecting, implementing and using an ITSM tool. When selecting an ITSM tool it is extremely important to identify the benefits that it will bring to the organization. In the implementation phase it is essential to have clear goals, good design work and sufficient training. This ensures that the tool will be used as it was designed and opposition in the organization toward this change will be minimal.Tutkimus tehtiin itSMF Finlandille, IT-palveluhallinnan yhteistyöfoorumille, joka pyrkii parantamaan IT-palvelunhallinnan toimintatapoja Suomessa ja maailmalla. IT-palvelunhallintaan kuuluu muun muassa loppukäyttäjille tarkoitetut tukipalvelut, tietojärjestelmien vikatilojen selvittäminen ja yhteydenpito tietojärjestelmien toimittajiin. IT-palvelunhallinnan käytännöt ovat olleet käytössä jo kauan, mutta käytäntöjä tukeva teknologia on kehittynyt ja tullut entistä monipuolisemmaksi. Tutkimuksen tavoitteena oli selvittää IT-palveluhallinnan työkalujen vaatimuksia sekä tutkia Suomen markkinoilla käytössä olevien IT-palvelunhallinnan työkalujen toiminnallisuuksia sekä niiden käyttökokemuksia. Tutkimuksen viitekehykseksi valittiin IT Infrastructure Library (ITIL®) -malli, josta on muodostunut parhaiden käytäntöjen ohjeistus IT-palvelunhallinnalle. Tutkimuksessa selvitettiin ITIL®:n suosituksia IT-palvelunhallinan teknologioiden osalta. Tämän lisäksi tutkimukseen valittiin yhdeksän työkalua. Kaikkien työkalujen käytöstä haastateltiin sekä toimittajaa että yhtä heidän asiakastaan. Haastattelujen perusteella selvitettiin työkalujen toiminnallisuuksia ja kuinka implementaatioprojektia tuetaan toimittajan puolelta sekä käyttäjäkokemuksia työkalun käytöstä ja implementointivaiheesta asiakkaan puolelta. ITIL® suosittelee IT-palvelunhallinnan työkalua organisaatioille tukemaan jokapäiväisiä toimintoja ja tuottamalla tietoa organisaation palveluista sekä tukemaan yrityksen koko elinkaarimallia. Tutkimuksessa mukana olleet työkalut olivat IT-palvelunhallinnan-ohjelmistoja eli työkaluja, jotka tukevat elinkaarimallin monta osaa. Tutkimuksessa ilmeni, että työkalut ovat tärkeitä yrityksille, mutta niitä ei kuitenkaan käytetä koko laajuudessaan. Käyttöönottoprojektit työkaluille olivat hyvin erilaisia, mutta usein hyvin menestyneitä. Jokaisessa tapauksessa työkalu auttoi organisaatiota toimimaan paremmin. Tämä tutkimus esittää asioita, jotka on hyvä pitää mielessään IT-palvelunhallinnan työkalua valitessa, implementoitaessa ja käytettäessä. Työkalua valitessa on tärkeää ymmärtää, mitä työkalun tulee tuoda yritykseen. Työkalun käyttöönotossa tärkeitä asioita ovat selkeät tavoitteet, hyvä suunnittelu sekä onnistunut koulutus. Nämä edesauttavat työkalun omaksumista yrityksessä sekä vähentävät mahdollista muutosvastarintaa

    Automatic Generation Of Supply Chain Simulation Models From Scor Based Ontologies

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    In today\u27s economy of global markets, supply chain networks, supplier/customer relationship management and intense competition; decision makers are faced with a need to perform decision making using tools that do not accommodate the nature of the changing market. This research focuses on developing a methodology that addresses this need. The developed methodology provides supply chain decision makers with a tool to perform efficient decision making in stochastic, dynamic and distributed supply chain environments. The integrated methodology allows for informed decision making in a fast, sharable and easy to use format. The methodology was implemented by developing a stand alone tool that allows users to define a supply chain simulation model using SCOR based ontologies. The ontology includes the supply chain knowledge and the knowledge required to build a simulation model of the supply chain system. A simulation model is generated automatically from the ontology to provide the flexibility to model at various levels of details changing the model structure on the fly. The methodology implementation is demonstrated and evaluated through a retail oriented case study. When comparing the implementation using the developed methodology vs. a traditional simulation methodology approach, a significant reduction in definition and execution time was observed
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