The ASSISTment system is a web-based tutor that is currently being used as an eighth and tenth-grade mathematics in both Massachusetts and Pennsylvania. This system represents its tutors as state-based "pseudo-tutors" which mimic a more complex cognitive tutor based on a set of production rules. It has been shown that building pseudo-tutors significantly decreases the time spent authoring content. This is an advantage for authoring systems such as the ASSITment builder, though it sacrifices greater expressive power and flexibility. A cognitive tutor models a student's behavior with general logical rules. Through model-tracing of a cognitive tutor's rule space, a system can find the reasons behind a student action and give better tutoring. In addition, these cognitive rules are general and can be used for many different tutors. It is the goal of this thesis to provide the architecture for using cognitive rule-based tutors in the ASSITment system. A final requirement is that running these computationally intensive model-tracing tutors do not slow down students using the pseudo-tutors, which represents the majority of ASSISTment usage. This can be achieved with remote computation, realized with SOAP web services. The system was further extended to allow the creation and implementation of user-level experiments within the system. These experiments allow the testing of pedagogical choices. We implemented a hint dissuasion experiment to test this experimental framework and provide those results.

JavaScript Object Notation (JSON) is a format for representing data. In this thesis we show how to capture the history of changes to a JSON document. Capturing the history is important in many applications, where not only the current version of a document is required, but all the previous versions. Conceptually the history can be thought of as a sequence of non-temporal JSON documents, one for each instant of time. Each document in the sequence is called a snapshot. Since changes to a document are few and infrequent, the sequence of snapshots largely duplicates a document across many time instants, so the snapshot model is (wildly) inefficient in terms of space needed to represent the history and time taken to navigate within it. A more efficient representation can be achieved by “gluing" the snapshots together to form a temporal model. Data that remains unchanged across snapshots is represented only once in a temporal model. But we show that the temporal model is not a JSON document, and it is important to represent a history as JSON to ensure compatibility with web services and scripting languages that use JSON. So we describe a representational model that captures the information in a temporal model. We implement the representational model in Python and extensively experiment with the model. Our experiments show that the model is efficient.

Cordova (Curated Online Reference Database Of Variation Annotations) is an out-of-the-box solution for building and maintaining an online database of genetic variations integrated with population study information and pathogenicity prediction results from popular algorithms. Our primary motivation for developing this system is to aid researchers and clinician-scientists in determining the clinical significance of genetic variations. To achieve this goal, Cordova provides an interface to review and manually or computationally curate genetic variation data as well as share it for clinical diagnostics and the advancement of research.

Scientific databases often need to be accessed from a variety of different applications. There are usually many ways to retrieve and analyse data already in a database. However, it can be more difficult to enter data which has originally been stored in different sources and formats (e.g. spreadsheets, other databases, statistical packages). This project focuses on investigating a generic, platform independent way to simplify the loading of databases. The proposed solution uses Web services as middleware to supply essential data management functionality such as inserting, updating, deleting and retrieval of data. These functions allow application developers to easily customise their own data entry applications according to local data sources, formats and user requirements. We implemented a Web service to support loading data to the Germinate database at the New Zealand Institute of Crop & Food Research (CFR). We also provided language specific client toolkits to help developers invoke the Web service. The toolkits allow applications to be easily customised for different platforms. In addition, we developed sample applications to help end users load data from their project data sources via the Web service. The Web service approach was evaluated through user and developer trials. The feedback from the developer trial showed that using Web services as middleware is a useful approach to allow developers and competent end users to customise data entry with minimal effort. More importantly, the customised client applications enabled end users to load data directly from their project spreadsheets and databases. It significantly reduced the effort required for exporting or transforming the source data.

In Service-Oriented Architectures, everything is a service and services can interact with each other when needed. Web services (or simply services) are loosely coupled software components that are published, discovered, and invoked across the Web. As the use of Web services grows, in order to correctly interact with the growing services, it is important to understand the business protocols that provide clients with the information on how to interact with services. In dynamic Web services environments, service providers need to constantly adapt their business protocols for reflecting the restrictions and requirements proposed by new applications, new business strategies, and new laws, or for fixing the problems found in the protocol definition. However, the effective management of such a protocol evolution raises critical problems: one of the most critical issues is to handle instances running under the old protocol when their protocol has been changed. Simple solutions, such as aborting them or allowing them to continue to run according to the old protocol, can be considered, but they are inapplicable for many reasons (e.g., the lose of work already done and the critical nature of work). We present a framework that supports service administrators in managing the business protocol evolution by providing several features, such as a set of change operators allowing modifications of protocols, a variety of protocol change impact analyses automatically determining which ongoing instances can be migrated to the new version of protocol, and data mining techniques inducing a model for classifying ongoing instances migrateable to the new protocol. To support the protocol evolution process, we have also developed database-backed GUI tools on top of our existing system. The proposed approach and tools can help service administrators in managing the evolution of ongoing instances when the business protocols of services with which they are interacting have changed.

Existing service matching approaches trade precision for recall, creating the need for humans to choose the correct services, which is a major obstacle for automating the service matching and the service aggregation processes. To overcome this problem, the matchmaker must automatically determine the correctness of the matching results according to the defined users' goals. That is, only service(s)-achieving users' goals are considered correct. This requires the high-level functional semantics of services, users, and application domains to be captured in a machine-understandable format. Also this requires the matchmaker to determine the achievement of users' goals without invoking the services. We propose the G+ model to capture the high-level functional specifications of services and users (namely goals, achievement contexts and external behaviors) providing the basis for automated goal achievement determination; also we propose the concepts substitutability graph to capture the application domains' semantics. To avoid the false negatives resulting from adopting existing constraint and behavior matching approaches during service matching, we also propose new constraint and behavior matching approaches to match constraints with different scopes, and behavior models with different number of state transitions. Finally, we propose two correctness-aware matching approaches (direct and aggregate) that semantically match and aggregate semantic web services according to their G+ models, providing the required theoretical proofs and the corresponding verifying simulation experiments.

全球資訊網的快速發展，已成為現代人生活中最主要的資訊媒介，使用者可以在網路上找到各種所需的資訊。然而，這些資訊是分散在各個網站上的，使用者必須分別從不同的來源取得所需的資訊。資訊的整合較之於單一的來源，往往能夠提供更多的價值，若能有一個整合性的資訊入口，並且能夠針對使用者的需求，提供使用者個人化的資訊，這些資訊對於使用者而言就會更有意義。 　　本研究利用XML Web Services的架構，將每個提供資訊的網站視為一個資源，以鬆散耦合(Loosely-Coupled)的方式將這些資源整合在單一的介面，從而讓使用者只需透過單一的入口，便可以獲得整合性的資訊資源。

Les réseaux à base de politiques (PBN) définissent un paradigme des plus prometteurs pour la gestion et le contrôle des ressources réseaux. COPS tend à être le protocole de facto pour l'utilisation de ce type d'applications. La question se pose de savoir comment déployer ce type de services pour permettre les échanges entre les différentes entités protocolaires du réseau (PEP et PDP). C'est à ce niveau que nous proposons de faire intervenir la notion de réseaux actifs, vu que ce paradigme permet d'intégrer du code exécutable aux paquets transférés et/ou nœuds en vue de distribuer et de configurer dynamiquement les services du réseau. D'autre part, une grande effervescence existe actuellement autour du déploiement des Web services sur Internet à l'aide du protocole SOAP. Toujours dans le cadre de l'Internet mais selon une perspective différente, la représentation sémantique des données, et grâce à la définition d'ontologies, permet aux logiciels d'interpréter intelligemment les données qu'elles gèrent et de ne plus jouer le rôle de simple équipement de stockage passif. La synergie entre les 4 paradigmes: PBN, Réseaux actifs, Web services, et représentation sémantique des données, présente une solution intégrée et portable des plus intéressantes pour la représentation des nœuds de l'architecture active, la conception, l'implémentation et le déploiement de services, et plus spécifiquement un service de gestion dynamique contrôlable et intelligent, dont les données (politiques et règles) sont représentés par une même ontologie.

<p>Utvecklingen går mot alltmer distribuerade IT-system, där ett flertal datorer kommunicerar med varandra. Detta gäller även försvarsmaktens ledningssystem. I dessa öppna och distribuerade system är olika säkerhetsfunktioner kritiska. En av dessa är att kunna verifiera identiteten hos den part som kommunikationen sker med. Detta görs oftast med hjälp av asymmetriska kryptooperationer, där identiteter kan verifieras med hjälp av öppet publicerade autentiseringsnycklar. Hanteringen av sådana nycklar kan centraliseras med hjälp av XML Key Management Specification. XKMS är en standard utvecklad av W3C som specificerar en Web Service för hantering av distribution, verifiering och registrering av öppna nycklar. I detta examensarbete har en del av en sådan service implementerats. Fokus har legat på distribution och verifikation av X.509-certifikat som är en ledande standard för att knyta ihop identiteter med nycklar. Slutligen har ett API till Java utvecklats för att på klientsidan underlätta nyttjandet av en XKMS-service.</p>

Sensor network web services have recently emerged as promising tools to provide remote management, data collection and querying capabilities for sensor networks. They can be utilized in a large number of elds among which Demand-Side Energy Management (DSEM) is an important application area that has become possible with the smart electrical power grid. DSEM applications generally aim to reduce the cost and the amount of power consumption. In the traditional power grid, DSEM has not been implemented widely due to the large number of households and lack of ne-grained automation tools. However by employing intelligent devices and implementing communication infrastructure among these devices, the smart grid will renovate the existing power grid and it will enable a wide variety of DSEM applications. In this thesis, we analyze various DSEM scenarios that become available with sensor network web services. We assume a smart home with a Wireless Sensor Network (WSN) where the sensors are mounted on the appliances and they are able to run web services. The web server retrieves data from the appliances via the web services running on the sensor nodes. These data can be stored in a database after processing, where the database can be accessed by the utility, as well as the inhabitants of the smart home. We showthat our implementation is e cient in terms of running time. Moreover, the message sizes and the implementation code is quite small which makes it suitable for the memory-limited sensor nodes. Furthermore, we show the application scenarios introduced in the thesis provide energy saving for the smart home.