The aim of this research is to investigate the performance of a bi-stable device using a single active element and to design a higher order all optical binary delta-sigma modulator (BΔΣM). A Delta sigma modulator has two important components that require enhancement to achieve robust modulation. The first component is the integrator which accumulates the error and at the same time leaks it. Here, the integrator is a single ring laser consisting of a semiconductor optical amplifier (SOA) and a filter to allow the light frequency of interest into the ring. The other component is the bi-stable device (called Schmitt trigger) that switches either ON (1) or OFF (0). There are different novel approaches to developing a bi-stable circuit. First, the coupled two ring lasers where each ring suppresses each other. Second, a novel idea that considered as a bi-stable device with single active element to achieve reduced power and reduce cost. This type of circuit is merged ring lasers with using single SOA. This system is modeled and its bistability hysteretic characteristics is investigated. The first bi-stable device is used to construct an all optical BΔΣM with 1st, 2nd and 3rd -order approaches. It performs better when the SOA bulk device is replaced by multi-quantum well (MQW) SOA.

Next Generation Networks (NGNs) aim to provide a unified network infrastructure to offer multimedia data and telecommunication services through IP convergence. NGNs utilize multiple broadband, QoS-enabled transport technologies, creating a converged packet-switched network infrastructure, where service-related functions are separated from the transport functions. This requires significant changes in the way how networks are managed to handle the complexity and heterogeneity of NGNs. This thesis proposes a Service Oriented Architecture (SOA) based management framework that integrates heterogeneous management systems in a loose coupling manner. The key benefit of the proposed management architecture is the reduction of the complexity through service and data integration. A network management middleware layer that merges low level management functionality with higher level management operations to resolve the problem of heterogeneity was proposed. A prototype was implemented using Web Services and a testbed was developed using trouble ticket systems as the management application to demonstrate the functionality of the proposed framework. Test results show the correcting functioning of the system. It also concludes that the proposed framework fulfils the principles behind the SOA philosophy.

No description available.

I enighet med teknikutvecklingen förändras även förutsättningarna för kostnadseffektiva IT-miljöer. Systemarkitekturen för mjukvarusystem förändras i samband med detta och verksamhetens systemdesign måste följa denna utveckling för att vara konkurrenskraftig på IT-marknaden.Implementeringar av Service Oriented Architecture, förkortat SOA, har i många fall visat sig vara lönsamma investeringar till en modernare arkitektur. Denna rapport förklarar på vilka sätt SOA kan vara kostnadseffektivt för verksamheter, samt identifierar kritiska framgångsfaktorer som är avgörande vid systemskiften till SOA.I kombination av en teoretisk litteraturstudie, analys av publicerade företagsfall och empirisk undersökning visar sig SOA-baserade lösningar vara kostnadseffektiva genom sänkta kostnader, tidsbesparingar och snabbare produktutveckling. Studien identifierar huvudsakligen fem kritiska framgångsfaktorer som är direkt kopplade till hur pass kostnadseffektiv en implementering av SOA kan komma att bli. / In unity with the technological evolution the conditions for cost-effective IT environments also changes. In this context, the architecture of software systems is changing and the business system design has to follow this development in order to be competitive on the IT market.Implementations of Service Oriented Architecture, abbreviated as SOA, have in many cases proven to be profitable investments to a modern architecture. This thesis explains in which ways SOA may turn out to be cost-effective for companies, and identifies critical success factors that are crucial within a system transition to SOA.The combination of a theoretical literature study, analysis of published business cases and empirical studies provided a result in which SOA-based solutions was cost-effective by reduced costs, time savings and faster product development. The study identifies five main critical success factors which are directly related to how cost-effective an implementation of SOA may be.

Affärsnytta är ett mångtydigt och svårdefinierat begrepp, men det är något som alla verksamheter vill uppnå.Uppsatsen avgränsar sig till särskilda kvalitativa egenskaper som definieras av ISO/IEC FDIS 25010:2010 under kapitlet "Quality in use". Uppsatsen går ut på att utvärdera de kvalitativa egenskaperna och om SOA (Service Oriented Architecture) bidrar till dessa samt inom vilken aspekt av affärsnytta. För att svara på frågan var det relevant att utvärdera begreppen Affärsnytta och Kvalitativ nytta samt definiera SOA.Resultatet fick vi genom kvalitativa intervjuer från fyra respondenter som har deltagit i ett lyckat SOA projekt och har goda kunskaper inom SOA och dess koppling till affärsnytta inom olika aspekter.Utifrån litteraturen och resultatet ser vi indikationer på att SOA bidrar till de utvalda kvalitativa egenskaperna. Resultatet visar även indikationer på att SOA bidrar till kvalitativ nytta och att det är en drivande kraft för strävan av affärsnytta. / Business value is ambiguous and very hard to define, but it is something that all enterprises strive for.The thesis focuses on specific quality characteristics defined by ISO / IEC FDIS 25010:2010 chapter "Quality in use". The thesis aims to evaluate the qualitative attributes and to find out if SOA (Service Oriented Architecture) contributes to these and in what aspect of business value. To answer the question it was relevant to define Business Value, Qualitative value and SOA.Our results are based on four qualitative interviews from respondents who have participated in a successful SOA project and have knowledge about SOA and it’s connection to business value in various aspects.We see indications that SOA contributes to the selected qualitative characteristics based on the litterature and result. The result also indicates that SOA contributes to qualitative value and that it is the driving force behind the pursuit of business value.

Bindings are used to make a software library accessible in languages other than those that the library was originally written for. However, creating and maintaining large amounts of bindings for every library is time-consuming and costly. An alternative approach to bringing functionality to more languages is to use a service-oriented architecture, where functionality is provided as services accessible from another process through message passing. Various middlewares exist to enable message passing between processes. In this thesis, some of the state of the art messaging middlewares are explored and evaluated them in terms of various criteria. Emphasis is given to their suitability for programmable built for industrial vehicles. Three of the most suitable middlewares are used to implement small systems based on a service-oriented architecture for further evaluation. The results indicate that the Data Distribution Service is the most promising candidate, owing to its interface description language, language support, and relatively low RAM and disk space usage. / Bindings används för att göra ett mjukvarubibliotek tillgängliga i andra språk än de som biblioteket till en början var gjort för. Att skapa och underhålla bindings för varje bibliotek är dock tidskrävande och kostsamt. Ett alternativt sätt att tillhandahålla funktionalitet till fler språk är att använda en tjänsteorienterad arkitektur där funktionalitet finns tillgänglig i tjänster som andra processer använder via meddelandeöverföring. Det finns flera mellanprogramvaror för meddelandeöverföring mellan processer. I denna uppsats undersöks några av de främsta mellanprogramvarorna i förhållande till en mängd kriterier, med fokus på hur lämpliga de är för programmerbara displays gjorda för industriella fordon. För ytterligare utvärdering används de tre mest lämpliga mellanprogramvarorna för att implementera små system baserade på en tjänstorienterad arkitektur. Resultaten tyder på att Data Distribution Service är den mest lovande kandidaten tack vare dess Interface Description Language, språkstöd och relativt låga användning av RAM och diskutrymme.

Los efectos de la luz lenta y luz rápida (SFL) han mostrado unas capacidades excepcionales sobre el control dinámico de la velocidad de la luz en diferentes medios. Una de las motivaciones más estimulantes redica en la potente aplicación de estos sistemas en el marco del procesado fotónico de señales de radio frecuencia (RF). En esta tesis doctoral, se evalúan las prestaciones de las plataformas de SFL actuales para desarrollar múltiples tareas que se requieren en el campo de la fotónica de microondas (MWP) con el valor añadido de sintonizabilidad y operación en banda ancha. En esta contexto, el scattering de Brillouin estimulado (SBS) tanto en fibra estándar como en fibra mantenedora de polarización (PMF), de redes Bragg (FBG), amplificadores ópticos de semiconductor (SOA) y cristales fotónicos (PhC) han sido las tecnologías bajo estudio. Desde escalas del orden de km hata mm, estas plataformas de SFL representan la evolución hacia la consolidación de componentes y subsistemas de MWP en circuitos fotónicos integrados (PIC). Diversos modelos analíticos y numéricos se han desarrollado con el objetivo de entender los procesos físicos que goboernan la porpagación a través de las diferentes plataformas de SFL, así como para describir los enfoques de MWP propuestos. Además, a través de las plataformas presentadas se ha llevado a cabo el análisis de las prestaciones de dos de las funcionalidades clave que se requieren para el procesado fotónico de señales de microondas, desfasadores sintonizables y retardos verdaderos (TTD). Se ha propuesto un sistema de TTD basado en la llamada técnica de sintonización separada de la portadora (SCT) a través de los efectos de SBS en fibrras estándr. Se ha evaluado la interacción del SBS en PMF con el propósito de desarrollar redes de Brillouin dinámicas (DBG), cuya fase generada ha sido fruto de estudio. Por otro lado, también se ha demostrado un sistema de densado distribuido basado en la reflexión continua de un pulso estrecho a lo la / Sancho Durá, J. (2012). Photonic-assisted RF Signal Processing based on Slow and Fast Light Technological Platforms [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/16471

(略) / Service-oriented Architecture (SOA) paradigm is an emerging architectural blueprint which enables flexible process-oriented application systems. While more and more enterprises plan to adopt SOA to increase reusability and flexibility of their business processes, the readiness of this technology becomes important to enterprises. However, previous SOA studies focus mainly on the technical issues but ignore the organizational or managerial issues. To fill this gap, this research aims to explore the factors of adopting SOA. Developed upon institutional theory and diffusion of innovation theory, we not only consider the technical factors with SOA adoption, but also pay attention to factors related with organizations and IT innovations. Furthermore, a content analysis of online Webs, blogs, and forums is taken to verify our research framework, and research findings indicate the relative advantage of SOA, compatibility of SOA, the characteristics of decision makers, culture, IT capability, and SOA socioeconomic characteristics are the most important drivers for SOA adoption. The contribution is summarized in two folds: (1) enterprises can use this framework as a reference to diagnose their organization conditions and then make a decision to adopting SOA; and (2) researchers can develop their study upon the constructs of this framework.

Le travail de recherche présenté dans ce mémoire s’intéresse aux problèmes d’interopérabilité dans le domaine du Product Lifecycle Management (PLM) et vise à proposer une méthodologie capable d’y remédier. Nous définissons l’objectif stratégique du PLM comme la maîtrise de la complexité qui caractérise le développement et le suivi des produits. Dans ce cadre, l’objectif de l’interopérabilité est le contrôle des interactions entre constituants de ce système complexe PLM. Nous montrons que cet objectif est atteint si on assure la continuité et la conservation du flux sémantique qui circule dans le système. Notre étude est restreinte aux seuls domaines de la conception et de la production, mais a l’ambition de pouvoir s’appliquer à d’autres domaines. La continuité du flux sémantique est assurée par une architecture que nous avons baptisée « médiation multi-échelle orientée services ». Le cœur de cette architecture, le médiateur, se charge d’orienter les flux sémantiques vers les systèmes concernés, et met en correspondance sémantique les informations échangées en s’appuyant sur un méta-modèle d’unification. Nous montrons que pour assurer la robustesse, la flexibilité et l’agilité du système ainsi constitué, il faut privilégier le choix d’un méta-modèle standard générique et extensible. A cet effet, nous proposons une cartographie du standard STEP permettant de choisir le méta-modèle pertinent. Nous illustrons le choix et la définition de ce méta-modèle dans le cas de deux problèmes d’interopérabilité des domaines de la conception et de la production : l’interopérabilité CAO/PDM et l’interopérabilité PDM/ERP. Nous expliquons notre démarche dans la mise en œuvre de la norme PLCS. Par ailleurs, nous introduisons un modèle d’annotations sémantiques du produit qui permet de reconstruire des vues multiples correspondant à différents besoins métiers. Un ensemble de démonstrateurs permet de valider nos propositions et nos résultats. / Research work presented in this manuscript deals with interoperability issues in the domain of Product Lifecycle Management (PLM) and aims at proposing a methodology able to remedy it. We define the objective of PLM as the control of the complexity that characterizes the development and monitoring of the product. In this context, the objective of the interoperability is to control the interactions between components of this PLM complex system. We demonstrate that this objective is reached if we ensure the continuity and the conservation of the semantic flow inside the system. Our study is restricted to design and production fields, but can be extended to other domains. The continuity of the semantic flow is guaranteed by an architecture that we entitled “service-oriented multi-layered mediation”. The main part of this architecture, the mediator, takes care to orientate the semantic flows towards the adequate systems, and semantically connect the exchanged information by relying on an unification meta-model. We demonstrate that, to ensure the robustness the flexibility and the agility of the so-constituted system, the choice of a generic and extensible standard meta-model should be favored. We thus proposed a mapping of STEP standard allowing to choose the adequate meta-model. We illustrate the choice and the definition of this meta-model in the case of two interoperability problems in the design and production domains: the interoperability CAD/PDM and the interoperability PDM/ERP. We illustrate our methodology in the implementation of the PLCS standard. Moreover, we introduce a model of product semantic tags that allows to rebuild the multiple product views corresponding to different actor needs. A set of demonstrators validate our propositions and our results.

A presente tese de doutorado propõe uma arquitetura de cloud broker para ambientes de computação em nuvem híbrida. Um cloud broker tem o objetivo de executar a mediação entre clientes e provedores, recebendo requisições dos clientes e encaminhando-as ao serviço do provedor que melhor se adaptar aos requisitos de qualidade de serviço (QoS) solicitados. A arquitetura de broker de serviços com QoS proposta denomina-se QBroker, características de implementação de seu modo de operação bem como sua interação com os recursos virtuais de um ambiente de nuvem são apresentadas. O modelo de nuvem considerado foi o de nuvem híbrida com uma caracterização de arquitetura orientada a serviços (SOA) na qual serviços remotos são disponibilizados aos clientes. A política de escalonamento de tarefas desenvolvida para o QBroker foi a de intermediação de serviços, considerando tratativas de QoS, diferenciação das instâncias de serviços (SOA) e alocação dinâmica de serviços. Além disso, toda a caracterização do modo de operação do QBroker foi baseada no conceito de intermediação do modelo de referência de nuvem do NIST. O componente QBroker foi introduzido numa arquitetura de computação em nuvem BEQoS (Bursty Energy and Quality of Service), desenvolvida no Laboratório de Sistemas Distribuídos e Programação Concorrente do ICMC-USP de São Carlos. Avaliações de desempenho para a implementação da arquitetura QBroker foram conduzidas por meio de programas de simulação com uso da API do simulador CloudSim e da arquitetura CloudSim-BEQoS. Três cenários experimentais foram avaliados e, segundo a análise de resultados efetuada, foi possível validar que as características arquiteturais implementadas no QBroker resultaram em significativo impacto nas variáveis de resposta consideradas. Assim, foi possível comprovar que o uso do QBroker como mecanismo de mediação em ambientes de nuvem híbrida com SOA promoveu ganhos em desempenho para o sistema de nuvem e permitiu melhoria na qualidade dos serviços oferecidos. / This doctoral thesis proposes a cloud broker architecture for hybrid cloud computing environments. A cloud broker aims to perform mediation between clients and providers, receiving customer requests and forwarding them to the service provider that best suits the requested QoS requirements. The broker architecture services with QoS proposal is called QBroker. Implementation features of its mode of operation as well as its interaction with the virtual resources from a cloud environment are presented. The cloud deployment model was considered a hybrid cloud with a characterization of service-oriented architecture (SOA) in which remote services are available to customers. The task scheduling policy developed for QBroker was the intermediation of services, considering negotiations of QoS, differentiation of services instances and dynamic allocation of services. Moreover, the entire characterization of QBroker operation mode is based on the intermediation concept of the NIST cloud reference model. The QBroker component was introduced into a cloud computing architecture BEQoS (Bursty, Energy and Quality of Service), developed in the Laboratory of Distributed Systems and Concurrent Programming at ICMC-USP. Performance evaluations analysis the of results of QBroker architecture were conducted through simulation programs using the CloudSim simulator API and CloudSim-BEQoS architecture. Three experimental scenarios were evaluated and, according to analysis of the results, it was possible to validate that the architectural features implemented in QBroker resulted in significant impact on response variables considered. Thus, it was possible to prove that the use of QBroker as mediation mechanism in hybrid cloud environments with SOA promoted performance gains for the cloud system and allowed improvement in the quality of services offered.