Σκοπός της εργασίας αυτής ήταν η θεωρητική ανάλυση των web services και η υλοποίηση ενός ηλεκτρονικού καταστήματος. Για να γίνει κατορθωτή η υλοποίησή του χρησιμοποιήθηκε ένα σύστημα διαχείρισης περιεχομένου, το Joomla. Το Joomla είναι ένα βραβευμένο σύστημα διαχείρισης περιεχομένου το οποίο μας δίνει τη δυνατότητα να οικοδομήσουμε ιστοσελίδες και ισχυρές online εφαρμογές .Είναι γραμμένο σε php, αποθηκεύει δεδομένα MySQL και περιλαμβάνει χαρακτηριστικά όπως η προσωρινή αποθήκευση σελίδας , RSS feeds, printable εκδόσεις των σελίδων, αναβοσβήνει ειδήσεις, blogs, δημοσκοπήσεις και έρευνα. Με τη βοήθειά του δημιουργήσαμε ένα ηλεκτρονικό κατάστημα και συγκεκριμένα ένα ηλεκτρονικό βιβλιοπωλείο που περιέχει δυο κατηγορίες βιβλίων. Με κλικάρισμα σε κάθε βιβλίο προβάλλονται οι λεπτομέρειες του προιόντος και δίνεται η δυνατότητα αγοράς του. / -

Este trabalho de mestrado apresenta a modelagem, a prototipação e os resultados do desenvolvimento de um middleware para composição dinâmica de Web Services denominado DWSC-M (Dynamic Web service Composition Middleware). O objetivo principal desse middleware é permitir que serviços sejam compostos dinamicamente considerando aspectos de qualidade de serviço na escolha dos serviços que fazem parte de um fluxo de composição. Para complementar o funcionamento do middleware DWSC-M foram propostos dois algoritmos para seleção de Web Services: o primeiro utiliza seleção aleatória e o segundo utiliza distância Euclidiana para seleção de serviços e considera, para tal finalidade, os parâmetros de QoS enviados pela requisição do cliente do serviço / This work presents the modeling, the prototype and the results of the developing of a middleware for dynamic composition of Web Services named DWSC-M (Dynamic Web Service Composition Middleware). The main focus of this middleware is to allow services being dynamically composed, considering aspects of quality of service in the choice of services that are part of the composite flow. Complementing the operation of the DWSC-M middleware two algorithms were proposed for Web Services selection : the first one uses Random selection and the second one uses Euclidean Distance for the selection of services and considers for this purpose the QoS parameters sent by the client service request

Geographic information is critical to GIS applications located remotely for executing business operations. GIS applications need to interoperate to be able to share information for analysis and decision making process. Heterogeneity and complexity of information models and structures limit the data flow and application interoperation. Advancements in Internet technologies provided new opportunities for delivering spatial information to remote users. However, spatial data delivered is in proprietary structures, limiting the utility to GIS applications. To enable information flow between GIS applications a portable data modeling approach is necessary. However, geographic information is inherently complex to model. A comprehensive and standardized vocabulary to model characteristics of geographic entities is required. Furthermore applications with the need to share information should have an agreement on information structure and content exchanged. This research presents GML representation to provide interoperable spatial data services. The objective is achieved by providing an open framework to model, encode and delivery geographic information. The results of this research show that it is possible to develop interoperable spatial data services through service oriented architecture.

Web services transactions have some unique characteristics. A Web transaction may be composed of a number of individual Web services, executed across multiple loosely coupled autonomous systems. Each Web service may be executed on an independent system belonging to an independent provider. There raises the question whether Web transactions can and should be maintained as a single business unit in a similar way to how transactions are maintained in classical database systems. In classical database systems, the transaction management protocol and mechanism are constrained by the primary properties of atomicity, consistency, isolation and durability (ACID). These ACID properties are the cornerstone of maintaining data integrity in transaction management. However, ACID properties were meant for centralised systems and are better suited for short transactions. Unlike short transactions, Web services transactions may be long-running; they can take hours or even days depending on the application. Composing certain actions from loosely coupled distributed business processes across multiple distributed applications is one of the essentials of Web services transactions. The classic ACID model, which is tightly coupled, is therefore seen as too rigid to support all the requirements of the new Web transactions model. The research proposes a system that increases throughput while maintaining the consistency and correctness required by the particular applications that are using the model; the system is known as AuTrA (Adaptable user-defined Transaction relaxed Approach). AuTrA allows relaxation of each ACID property. The model is adaptable to meet different situations with different characteristics. For instance, in some cases it will be appropriate to relax atomicity, whereas in others it may be appropriate to relax isolation and atomicity while maintaining consistency. The research explores how transaction support for Web services can be customised to suit the needs of varying applications and result in improved service. The AuTrA prototype has been implemented. The experimental results show that the AuTrA application is able to support the basic features of Web services transaction management, allowing users to specify their correctness requirements, and it can increase throughput of transactions in models in a flexible and reliable manner. Additional facilities allow users to specify application-specific, non-ACID criteria that can increase throughput. Safeguards have also been implemented to prevent execution of inappropriate user specifications, such as relaxation of properties that may damage data integrity. AuTrA can be used as a tool by software developers who need to compose applications from independent Web services and who wish to build applications which result in improved performance while maintaining application-required consistency.

As the population of the Internet users increases, various Web services, which are based on a set of standardized technologies, are now offered through the Internet. However, as the market becomes more competitive, atomic Web services are not sophisticated enough to meet users¡¦ needs, and the concept of Web services-based workflow emerges accordingly. Web services-based workflow is a workflow composed of several related activities, aiming to achieve certain task, and for each activity, there can be a set of candidate Web services to be selected. The goal is to make a selection, which optimizes the QoS of the entire workflow. Although numerous methods are proposed to solve this QoS-based Web services selection problem, most of them are based on a static QoS model, which cannot accurately reflect the real QoS measures, and as a result, methods based on this static model will not necessarily derive the optimal solution even in the average case. Therefore, in this thesis, we adopt a probability-based model, which represents QoS measures as probability mass functions, and propose a branch and bound algorithm for selecting Web services from a set of candidate Web services. Under this QoS model, the goal is to maximize the probability of meeting the QoS goal subject to some QoS constraints. As demonstrated by the results of our experiments, it is much more probable for a workflow to meets the QoS goal by executing the selection derived by the probability-based approach.

The last decade has demonstrated steady growth and utilization of Web Service technology. While Web Services have become significant in a number of IT domains such as eCommerce, digital libraries, data feeds, and geographical information systems, common portals or registries of Web Services require manual publishing for indexing. Manually compiled registries of Web Services have proven useful but often fail to include a considerable amount of Web Services published and available on the Web. We propose a system capable of finding, binding, and integrating Web Services into an index in an automated manner. By using a combination of guided search and web crawling techniques, the system finds a large number of Web Service providers that are further bound and aggregated into a single portal available for public use. Results show that this approach is successful in discovering a considerable number of Web Services in the GIS(Geographical Information Systems) domain, and demonstrate improvements over existing methods of Web Service Discovery.

Made available in DSpace on 2015-03-05T13:56:59Z (GMT). No. of bitstreams: 0 Previous issue date: 16 / Hewlett-Packard Brasil Ltda / Os serviços e as aplicações de computação móvel possuem exigências para o seu bom funcionamento, cujo atendimento é dificultado em virtude do ambiente altamente dinâmico em que estão inseridos. Nesse ambiente, o gerenciamento passa a ser peça chave para propiciar o funcionamento harmonioso tanto da infra-estrutura física, quanto das aplicações. As soluções existentes para essa finalidade se restringem à monitoração dos recursos de hardware, não oferecendo mecanismos para o gerenciamento das aplicações executadas nos dispositivos portáteis. Esta dissertação propõe uma arquitetura para gerenciamento de ambientes de computação móvel que permite obter e disseminar, de forma flexível, informações sobre o funcionamento dos dispositivos e, sobretudo, das aplicações. A arquitetura é baseada no padrão Web Services Distributed Management, que propõe o emprego de serviços Web na modelagem de interfaces de gerenciamento. A dissertação apresenta, ainda,resultados obtidos com a instanciação da arquitetura em um ambiente / Mobile computing services and applications pose special requirements to run properly, whose satisfaction is hampered due to the highly dynamic environment where they are executed. In this environment, management becomes an important element to enable harmonious functioning of both the mobile physical infrastructure and the applications. Current solutions are restricted to resource monitoring, and do not provide mechanisms to manage the applications running on top of the mobile devices. This work proposes an architecture to manage mobile computing environments, which allows one to obtain and disseminate, in a flexible manner, information about the devices and the applications. The architecture is based on the Web Services Distributed Management standard. This work also presents results obtained with the instantiation of the architecture in a real setup

Researchers have spent years understanding resource utilization to improve scheduling, load balancing, and system management through short-term prediction of resource utilization. Early research focused primarily on single operating systems; later, interest shifted to distributed systems and, finally, into web services. In each case researchers sought to more effectively use available resources. Since schedulers are required to manage the execution of multiple programs every second, short-term prediction has focused on time frames ranging from fractions of a second to several minutes. The recent increase in the number of research studies about web services has occurred because of the explosive growth and reliance on these services by most businesses. As demand has moved from static to dynamic content, the load on machine resources has grown exponentially, periodically resulting in temporary loss of service. To address these short-term denial-of-service issues, researchers have tried short-term prediction to manage scheduling of service requests. What researchers have not considered is that the same methods used for single step short-term prediction can also be used for long-term prediction if a coarse granularity of samples is used. Instead of using one or more samples per second, a coarser aggregate of minutes or hours more accurately emulates the long-term patterns. This research has shown that simple moving averages and exponential moving averages as a prediction technique can be used to more accurately predict hourly, daily, and weekly seasonal patterns of resource utilization for web servers. Additionally, this research provides a foundation where using a resource prediction within a confidence interval range could be more useful to an administrator or system software than a single prediction point. When the focus shifts to a range, a set of probabilities can establish normal function within that system. For distributed systems, it will provide the ability to notify other systems when resource utilization is no longer normal before that system is unable to issue a notice of overloading. For web systems it can be used to provide a warning, permitting the instantiation of a second system to begin load balancing during unscheduled heavy loads. In both cases, the availability of the system can be improved by predicting a resource utilization level and the confidence interval within which that resource use has historically fallen.

In the modern geographic information systems, COTS software has been playing a major role. However, deploying heterogeneous GIS software has the tendency to form fragmented data sets and to cause inconsistency. To accomplish data consolidation, we must achieve interoperability between different GIS tools. In my thesis project, I developed Vector and Raster Data Adapters to implement the spatial data consolidation. I deployed ArcIMS to publish the spatial data and metadata onto Internet. Furthermore, the SOAP-Based GIS Web services are implemented to achieve the enterprise information system integration. The contribution of ours in this project is we have streamlined the COTS GIS server, the J2EE coordinator server, the web service provider components, and the COTS web publishing tools into a hybrid web service architecture, in which the enterprise information system integration, the web publishing, and the business-to business online services are uniformed.

Regression testing is essential to ensure software quality. Regression Test-case selection is another process wherein, the testers would like to ensure that test-cases which are obsolete due to the changes in the system should not be considered for further testing. This is the Regression Test-case Selection problem. Although existing research has addressed many related problems, most of the existing regression test-case selection techniques cater to procedural systems. Being academic, they lack the scalability and detail to cater to multi-tier applications. Such techniques can be employed for procedural systems, usually mathematical applications. Enterprise applications have become complex and distributed leading to component-based architectures. Thus, inter-process communication has become a very important activity of any such system. Messaging is the most widely employed intermodule interaction mechanism. Today's systems, being heavily internet dependent, are Web-Services based which utilize XML for messaging. We propose an RTS technique which is specifically targeted at enterprise applications.