Σκοπός της διπλωματικής είναι η ανάπτυξη ενός ολοκληρωμένου σετ σημειώσεων για προγραμματισμό φορητών συσκευών με Windows Mobile και για τεχνολογίες ανάπτυξης εφαρμογών για κινητά.Με το πακέτο του .NET Compact Framework και το Visual Studio από κοντά, η διπλωματική αυτή συμβουλεύεται δειγματικούς κώδικες και εφαρμογές για να παρουσιάσει τις δυνατότητες του κόσμου αυτού των Windows εν κινήσει καθώς και τους περιορισμούς που θέτει η κίνηση αυτή σε σχέση με ένα σταθερό υπολογιστή. Αφού διαλέξει κάποιος την κινητή πλατφόρμα στην οποία στοχεύει να αναπτύξει τις εφαρμογές του και τα εργαλεία που θα χρησιμοποιήσει(και τα 2 παρουσιάζονται στον αναγνώστη με έμφαση στη λεπτομέρεια) ξεκινάει από ένα πρώτο χαμηλό προγραμματιστικό επίπεδο όπου λαμβάνει την βασική γνώση ώστε να ξεκινήσει με την ανάπτυξη μιας κινητής εφαρμογής.Γνωρίζει το υλικό των διαθέσιμων αυτή τη στιγμή κινητών συσκευών και εγκλιματίζεται στο περιβάλλον που καλείται να προγραμματίσει.Στη συνέχεια εισέρχεται πιο βαθιά στο υλικό και λογισμικό υπόβαθρο ώστε να προγραμματίσει αποτελεσματικές εφαρμογές με εργονομία και μοντέρνα λειτουργικότητα.Ζητήματα όπως η σύνδεση των κινητών εφαρμογών με βάσεις δεδομένων, η ασφάλεια, ο συγχρονισμός δεδομένων,η επικοινωνία με το τηλεπικοινωνιακό δίκτυο και η παροχή υπηρεσιών με Web Services εξετάζονται και παρουσιάζονται με παραδείγματα και εικόνες. Ευελπιστούμε πως ο αναγνώστης θα μπορέσει ύστερα από τη μελέτη της διπλωματικής αυτής να προγραμματίσει και σε προχωρημένο πλέον επίπεδο για τις αγαπημένες του εφαρμογές και να δοκιμάσει να εκμεταλευτεί τις νέες δυνατότητες και τεχνολογίες και να δημιουργήσει το δικό του κόσμο εν κινήσει! / -

Dynamic selection and composition of autonomous and loosely-coupled Web services is increasingly used to automate business processes. The typical long-running characteristic of business processes imposes new management challenges such as dynamic adaptation of running process instances. However, current process orchestration engines provide limited flexibility to dynamically adapt to changing runtime conditions (e.g., presence of faults). Additionally, current process specification languages exhibit some limitations regarding modularity of crosscutting management concerns. In particular, monitoring and adaptation logic is often scattered across several process definitions and intertwined with the business logic. This leads to monolithic and complex processes that are hard to understand, reuse, maintain, and evolve. To address these limitations, we developed a policy-based change management framework, named Manageable and Adaptable Service Compositions (MASC), to declaratively express crosscutting monitoring and process adaptation concerns in a separate and modular way. MASC policies use a set of simple, but flexible and relatively powerful, constructs to declaratively specify policies that govern: (1) discovery and selection of services to be used, (2) monitoring to detect the need for adaptation, (3) reconfiguration and adaptation of the process to handle special cases (e.g., context-dependant behaviour) and recover from typical faults in service-based processes. The identified constructs are executed by a lightweight service-oriented management middleware named MASC middleware. The adaptation is transparent because it preserves the original functional behaviour of the business process and does not tangle the adaptation logic with that of the business process. Additionally, policies do not have to be necessarily defined when designing the process; they can also be introduced later during deployment or at runtime. We implemented a MASC proof-of-concept prototype and evaluated it on Stock Trading case study scenarios. We conducted extensive studies to demonstrate the feasibility of the proposed techniques and illustrate the benefits of our approach in providing adaptive composite services using the policy-based approach. Our performance and scalability studies indicate that MASC middleware is scalable and the introduced overhead are acceptable.

Η ύπαρξη Διαδικτύου δημιούργησε την ιδιότητα του "Παγκόσμιου Πολίτη", δίνοντας την δυνατότητα σε όλους τους χρήστες του Διαδικτύου να μπορούν να έχουν πρόσβαση σε μια πληθώρα πληροφοριών, να επικοινωνούν μεταξύ τους, αλλά και να μπορούν και οι ίδιοι να μετατρέπονται από χρήστες του Διαδικτύου σε Παρόχους Υπηρεσιών μέσω του Διαδικτύου. Την σημερινή εποχή αναγνωρίζεται ως μια από τις σημαντικότερες εφαρμογές του Διαδικτύου και μάλιστα όχι άδικα, η τεχνολογία των Web Services, η οποία επιτρέπει στις εφαρμογές να επικοινωνούν μεταξύ τους ανεξαρτήτως πλατφόρμας και γλώσσας προγραμματισμού. Τα πρώτα web services σκόπευαν να είναι πηγές πληροφορίας τις οποίες μπορεί κανείς πολύ εύκολα να ενσωματώσει στις εφαρμογές του. Στην συνέχεια εξελίχθηκαν,προσφέροντας όλα τα δυναμικά τους χαρακτηριστικά ώστε να συνδυάζονται υπηρεσίες σε εφαρμογές. Στην παρούσα διπλωματική εργασία γίνεται μια εκτενής αναφορά στον σχεδιασμό και στην ανάπτυξη των Web Services. Αρχικά παρουσιάζονται οι βασικές τεχνολογίες των Web Services, η γλώσσα XML, το πρωτόκολλο SOAP, καθώς και οι WSDL και UDDI, οι οποίες αποτελούν τον "δομικό σκελετό" των Υπηρεσιών Διαδικτύου. Στην συνέχεια αντιμετωπίζουμε μια Υπηρεσία Web από την πλευρά του Παρόχου Υπηρεσίας. Αναφερόμαστε δηλαδή στους τρόπους υλοποίησης μιας τέτοιας εφαρμογής και στα βασικά εργαλεία προγραμματισμού της. Στο τελευταίο κομμάτι της παρούσας διπλωματικής παρουσιάζονται οι τελευταίες απαιτούμενες τεχνολογίες, ώστε να μπορούμε να μιλάμε για μια ολοκληρωμένη κατανεμημένη τεχνολογία των Υπηρεσιών Διαδικτύου. / The existence of the Internet created the position of "World Citizen", giving the opportunity to all users to be able to access a wealth of information, to communicate with each other, but also can be converted from users of Internet to Internet Service Providers. At this moment recognized as one of the most important applications of the Internet and not unjustly, the technology of Web Services, which allows applications to communicate regardless of platform and programming language. The initial web services intended to be sources of information which can easily incorporate into applications. Then web services were developed by offering all dynamic characteristics to combine services to applications. In this diploma become a comprehensive reference to the design and development of Web Services. Originally presented Initially the basic technologies of Web Services, the language XML, the protocol SOAP, WSDL and the UDDI, which is the "structural frame" of Web Services. Then we have a Web Service from the service provider side. We refer to the ways of implementation of such an application and on the basic development tools. In the last part of this thesis presented the latest technologies required so we can talk about a comprehensive distributed technology of the Web Services.

Neste trabalho é apresentado um sistema de instrumentação inteligente integrado com a arquitetura Web Services e desenvolvido em conformidade com as diretrizes estabelecidas na norma IEEE 1451.1. O protocolo de transmissão de dados do sistema é associado ao conceito das especificações dos transdutores e a um Web Service que permita a configuração remota do sistema de aquisição de dados. Através de uma interface de supervisão remota, acessível via Internet a partir de qualquer navegador, o usuário é capaz de identificar quais são os sensores inteligentes que estão conectados em uma rede, através de uma identificação única associada às suas características (tipo, formatação dos dados, etc.). Nesta mesma interface de apresentação o usuário tem a liberdade de selecionar o número de sensores que deseja ativar para efetuar algum monitoramento. Após a seleção dos sensores é disponibilizada uma interface de monitoramento que permite a visualização dos dados através de um gráfico bem como permite ao usuário salvar em um arquivo texto os dados coletados. Na mesma interface de monitoramento é disponibilizado o Web Service que permite alterar o intervalo de coleta de dados. Um conjunto de computadores em uma rede local (Intranet) simula a rede de sensores inteligentes. Nesta mesma rede está conectado o servidor responsável pela disponibilização da interface de supervisão remota. / In this work is presented the integration of an established system of intelligent instrumentation with the Web Service?s architecture, in accordance with the IEEE 1451.1 standard. It is suggested the association of a data-communication protocol with the concept of Transducer Electronic Data Sheet (TEDS) to a Web Service for making possible the remote configuration of a data acquisition system. Through a remote supervisor interface, accessible via Internet from any browser, the user can, at the first moment, identify which are the smart sensors connected in a network, using an unique identification associated to its characteristics (type, data formatting, etc.). In the same graphical interface the user can choose which sensors wants to monitor and, after the selection, will have available the monitoring interface that enables data visualization through a graph and allows the user to save the collected data in a text file. In the same monitoring interface the Web Service is also available; it admits modifications on the data collection interval. A group of computers in a local network (Intranet) simulates the smart sensors network. In the same network is connected a server responsible for supplying the remote supervisor interface.

O desenvolvimento de trabalhos em grupo tornou-se uma tarefa cada vez mais comum nos dias atuais. Com isso, houve também um crescimento na utilização e no desenvolvimento de aplicações computacionais que implementam os processos de apoio à cooperação entre as pessoas, as quais possibilitam um considerável ganho de produtividade nas tarefas realizadas pelo grupo. A integração de várias dessas aplicações pode resultar em um acréscimo de funcionalidades, aumentando as possibilidades de uso e a flexibilidade para o usuário. Com o objetivo de agregar funcionalidades e melhorar os potenciais usos dos sistemas de software, aplicações integradas possuem, em geral, mais funcionalidades e maiores possibilidades de uso do que aplicações isoladas. Assim, foi desenvolvido o WS4CSCW (Web Services for Computer Supported Cooperative Work), um Web Service que tem como objetivo facilitar a integração de ferramentas e sistemas CSCW. O WS4CSCW permite o gerenciamento de usuários, grupos, recursos, permissões e papéis de usuários e grupos, disponibilizando funcionalidades para aplicações voltadas ao trabalho em grupo, bem como para facilitar a integração entre essas aplicações, permitindo um co-funcionamento mais direto, consistente e coeso. / Nowadays, the achievement of tasks made in groups has become a habitual concern by people. In this way, a rise of using and developing computer programs that support cooperative work process has been noted. The programs aim to provide productivity improvements on work made by groups. Integrating the software could result in increasing functionalities, augmenting both its use possibilities and flexibility. Integrated softwares have, in general, more features and use's potential than isolated applications. As a result, WS4CSCW (Web Services for Computer Supported Cooperative Work) -- a Web Service to assist CSCW application's integration was developed. WS4CSCW allows management of users, groups, resources, permissions, and user and group roles, by making available functionalities to applications for group work, making easy the integration among these applications and providing a straighter, more cohesive and consistent cooperation.

Esta dissertação de mestrado propõe uma nova política de distibuição de requisições em cluster de web services, denominada Política Performance. Essa política provê uma distribuição transparente, flexível e dinâmica das requisições na plataforma em que é executada. Um estudo sistemático também é realizado para analisar a qualidade dos índices de carga empregados no contexto de web services e propõe um novo índice capaz de representar fielmente o desempenho dos web services e encapsular a complexidade estrutural da plataforma. Também é proposto em Módulo Gerenciador de Energia capaz de prover sustentabilidade à plataforma, reduzindo o consumo de energia elétrica sem prejudicar a alta confiabilidade na distribuição das requisições e com baixo impacto no tempo médio de resposta. Os estudos experimentais realizados neste trabalho mostraram que a Política Performance permitiu um melhor desempenho no atendimento das requisições realizadas à plataforma. EStes resultados referem-se a um desempenho superior a 70% no tempo médio de resposta, quando comparado ao desempenho demosntrado pela política padrão do Mod_cluster. O Módulo Gerenciador de Energia proporcionou uma redução de aproximadamente 30% no consumo de energia da plataforma mantendo a alta confiabilidade na distribuição das requisições / The Master\'s dissertation proposes a new for distribution of requests in cluster of web services, named policy Performance. This policy provides a transparent flexible and dynamic distribution of requests on the plataform. A systematic study is also conducted to example the quality of load indices used in the context of web services., and proposes a new index that accurately represent the performance of web services and encapsulate the complexity structural of the plataform. Also proposed is an Energy Manager Module capable of providing sustainability to the plataform, reducing power consumption without sacrificing high reliability in the distribution of request and low impact on the average response time. Our main results show that policy Performance has a better performance in handling requests sent to the plataform. Our results show a gain of performance higher than 70% in average responswetime when compared to the perormance demonstrated by the defaut policy Mod_cluster. The Power Manager Module reduced byapproximately 30% the energy consumption of the plataform even keeping the high reliability in the distribution of requests

Esta tese de doutorado analisa o impacto gerado pela virtualização assistida por hardware, de terceira geração, no desempenho de aplicações baseadas em SOA do tipo CPU-bound e memory-intensive, bem como nas operações de marshalling e unmarshalling de mensagens SOAP executadas nas bibliotecas dos servidores de aplicação. A partir dessa análise, concluiu-se que os recursos disponibilizados pela plataforma de hardware, principalmente no gerenciamento de memória, eliminam a sobrecarga gerada pela virtualização baseada em tradução binária, elevando os hypervisores bare-metal a um novo patamar, onde aplicações executadas sobre tais virtualizadores obtém, frequentemente, desempenho superior àquelas executadas em plataformas não virtualizadas. Assim, modificações nos modelos de desempenho de aplicações baseadas em SOA atualmente em uso são propostas, de acordo com a análise desenvolvida, para que reflitam os resultados obtidos de forma realista / This PhD thesis analyzes the impact caused by third generation hardware-assisted virtualization on the performance of CPU-bound and memory-intensive SOA-based applications, as well as the impact caused on the marshaling and unmarshalling operations of the SOAP messages executed on the libraries of the application servers. From this analysis is concluded that the resources provided by the hardware platform, mainly considering the memory management, eliminate the overload generated by virtualization based on binary translation, raising the bare-metal hypervisors to a new level, where applications running on these hypervisors reach better performance when compared to those applications running on platforms not virtualized. Thus, modifications on the performance models for SOAbased applications currently in use are proposed accordingly to the analysis developed, aiming at reflecting the results obtained in a realistic fashion

Web services discovery is the process of finding the right Web services that best match the end-users’ functional and non-functional requirements. Artificial intelligence, natural language processing, data mining, and text mining techniques have been applied by researchers in Web services discovery to facilitate the process of matchmaking. This thesis contributes to the area of Web services discovery and recommendation, adopting the Design Science Research Methodology to guide the development of useful knowledge, including design theory and artifacts. The lack of a comprehensive review of Web services discovery and recommendation in the literature motivated us to conduct a systematic literature review. Our main purpose in conducting the systematic literature review was to identify and systematically compare current clustering and association rules techniques for Web services discovery and recommendation by providing answers to various research questions, investigating the prior knowledge, and identifying gaps in the related literature. We then propose a conceptual model and a typology of Web services discovery systems. The conceptual model provides a high-level representation of Web services discovery systems, including their various elements, tasks, and relationships. The proposed typology of Web services discovery systems is composed of five groups of characteristics: storage and location characteristics, formalization characteristics, matchmaking characteristics, automation characteristics, and selection characteristics. We reference the typology to compare Web services discovery methods and architectures from the extant literature by linking them to the five proposed characteristics. We employ the proposed conceptual model with its specified characteristics to design and develop the multi-layer data mining architecture for Web services discovery using word embedding and clustering techniques. The proposed architecture consists of five layers: Web services description and data preprocessing; word embedding and representation; syntactic similarity; semantic similarity; and clustering. In the first layer, we identify the steps to parse and preprocess the Web services documents. Bag of Words with Term Frequency–Inverse Document Frequency and three word-embedding models are employed for Web services representation in the second layer. Then in the third layer, four distance measures, including Cosine, Euclidean, Minkowski, and Word Mover, are studied to find the similarities between Web services documents. In layer four, WordNet and Normalized Google Distance are employed to represent and find the similarity between Web services documents. Finally, in the fifth layer, three clustering algorithms, including affinity propagation, K-means, and hierarchical agglomerative clustering, are investigated to cluster Web services based on the observed documents’ similarities. We demonstrate how each component of the five layers is employed in the process of Web services clustering using random-ly selected Web services documents. We conduct experimental analysis to cluster Web services using a collected dataset of Web services documents and evaluating their clustering performances. Using a ground truth for evaluation purposes, we observe that clusters built based on the word embedding models performed better compared to those built using the Bag of Words with Term Frequency–Inverse Document Frequency model. Among the three word embedding models, the pre-trained Word2Vec’s skip-gram model reported higher performance in clustering Web services. Among the three semantic similarity measures, path-based WordNet similarity reported higher clustering performance. By considering the different words representations models and syntactic and semantic similarity measures, the affinity propagation clustering technique performed better in discovering similarities among Web services.

Linklets are location-independent web services, which consume and produce Linked Data resources. These resources form a web of data - the semantic web - that is an abstraction of the web 2.0. However, enterprises are reluctant to provide valuable Linked Data resources due to missing financial stimuli. Operations are not representable in the semantic web. Linklets aim to solve both problems. Previous work developed a prototype. The goal of this thesis is to enhance it by a component model, a formal description and a permission model. A business model has to be developed. This thesis follows a bottom-up approach. The formalization of the Linklet concept creates a foundation. Then, an improved architecture and its reference implementation are studied. It is evaluated by tests, show cases and economic considerations. The resulting component system is based on web-service component systems, while a sandbox concept is the core of the permission model. The formal description shows limits of OWLs open world assumption. A platform leader strategy is the foundation for the business model. In conclusion, the advantages of the Linklet concept provide a way to enhance and monetize the value of the semantic web. Further research is required; the practical use has to be considered.

Linklets are location-independent web services, which consume and produce Linked Data resources. These resources form a web of data - the semantic web - that is an abstraction of the web 2.0. However, enterprises are reluctant to provide valuable Linked Data resources due to missing financial stimuli. Operations are not representable in the semantic web. Linklets aim to solve both problems. Previous work developed a prototype. The goal of this thesis is to enhance it by a component model, a formal description and a permission model. A business model has to be developed. This thesis follows a bottom-up approach. The formalization of the Linklet concept creates a foundation. Then, an improved architecture and its reference implementation are studied. It is evaluated by tests, show cases and economic considerations. The resulting component system is based on web-service component systems, while a sandbox concept is the core of the permission model. The formal description shows limits of OWLs open world assumption. A platform leader strategy is the foundation for the business model. In conclusion, the advantages of the Linklet concept provide a way to enhance and monetize the value of the semantic web. Further research is required; the practical use has to be considered.:1 Introduction 1.1 Motivation 1.2 Thesis 1.3 Contributions of This Work 1.4 Overview 2 Background 2.1 Preliminaries 2.1.1 Linked Data 2.1.2 Composition Models 2.1.3 Java 2 Security Permission Model 2.1.4 OSGi 2.1.5 Related Work 2.2 Formalization of Linklets 2.2.1 Definition 2.2.2 Analogy to Pipes and Filters 2.2.3 Analogy to Database Operators 2.2.4 Related Work 3 Enhancement of the Linklet Architecture 3.1 Linklet Composition 3.1.1 Requirements 3.1.2 Existing Approaches 3.1.3 Possible Approaches 3.1.4 Architecture 3.1.5 Outlook 3.2 Formal Description 3.2.1 Requirements 3.2.2 Mathematical Formalization 3.2.3 Existing Approaches 3.2.4 Architecture 3.2.5 Outlook 3.3 Permission Model 3.3.1 Requirements 3.3.2 Related Work 3.3.3 Permission Model 3.3.4 Security Architecture 3.3.5 Outlook 4 Implementation and Test 4.1 Implementation 4.1.1 Design Decisions 4.1.2 Static View 4.1.3 Dynamic View 4.2 Test 4.2.1 Test Plan 4.2.2 Test Design Specification 4.2.3 Test Realization 4.2.4 Test Results 5 Application Areas for Linklets 5.1 Business Model 5.1.1 Product Innovation 5.1.2 Infrastructure Management 5.1.3 Customer Interface 5.1.4 Financial Aspects 5.1.5 Conclusion 5.2 Show Cases for Linklets 5.2.1 Restaurant Scenario 5.2.2 Annotation Scenario 5.2.3 eBay Scenario 6 Discussion 6.1 Results 6.2 Evaluation 6.3 Future Work 6.4 Conclusion A Ontology B First Steps With Linklets B.1 Development of the Linklet Artifact B.1.1 Adoption of the LinkletActivator Class B.1.2 Development of the Linklet Class B.2 Start of the Linklet