The semantic integration of geographically distributed and heterogeneous data resources still remains a key challenge in Grid infrastructures. Today's mainstream Grid technologies hold the promise to meet this challenge in a systematic manner, making data applications more scalable and manageable. The thesis conducts a thorough investigation of the problem, the state of the art, and the related technologies, and proposes an Architecture for Semantic Integration of Data Sources (ASIDS) addressing the semantic heterogeneity issue. It defines a simple mechanism for the interoperability of heterogeneous data sources in order to extract or discover information regardless of their different semantics. The constituent technologies of this architecture include Globus Toolkit (GT4) and OGSA-DAI (Open Grid Service Architecture Data Integration and Access) alongside other web services technologies such as XML (Extensive Markup Language). To show this, the ASIDS architecture was implemented and tested in a realistic setting by building an exemplar application prototype on a HealthGrid (pilot implementation). The study followed an empirical research methodology and was informed by extensive literature surveys and a critical analysis of the relevant technologies and their synergies. The two literature reviews, together with the analysis of the technology background, have provided a good overview of the current Grid and HealthGrid landscape, produced some valuable taxonomies, explored new paths by integrating technologies, and more importantly illuminated the problem and guided the research process towards a promising solution. Yet the primary contribution of this research is an approach that uses contemporary Grid technologies for integrating heterogeneous data resources that have semantically different. data fields (attributes). It has been practically demonstrated (using a prototype HealthGrid) that discovery in semantically integrated distributed data sources can be feasible by using mainstream Grid technologies, which have been shown to have some Significant advantages over non-Grid based approaches.

The promise of telemedicine is great as observed in developed countries. However, its adoption in developing countries has been very slow. The Kenyan government approved telemedicine (use of ICT to overcome geographical barriers and increase access to health care services) as a strategic approach of improving healthcare delivery especially in the marginalised areas of the country. However, the adoption of telemedicine is further hindered in developing countries by the fact that the cost of implementing telemedicine technology is deemed high and the resources needed are scarce especially in the public sector. Extant literature on healthcare technological innovation indicates that organisation collaboration can expedite the adoption of telemedicine especially in developing countries. Since it is highlighted that empirical evidence on how organisation collaboration can facilitate telemedicine deployment in developing countries is still lacking, this research aims to develop a model to examine the potential of various organisation factors in facilitating telemedicine deployment in developing countries. This study employed a conceptual research framework to examine organisation factors that may influence organisation collaboration in facilitating telemedicine deployment in developing countries. A questionnaire survey was conducted in 50 private and public hospitals located in Eastern Kenya. 177 valid questionnaires were received and analysed using SPSS software (version 20). The findings of this research revealed that Kenyan hospitals collaborate with other organisations mainly to lessen budget restrained suffered during technological innovation process. Further, it was revealed that organisation affiliation might enhance their ability to adopt telemedicine. Organisation affiliation was observed to significantly influence organisation resources, organisation’s innovation acceptance, organisation’s innovative capacities, organisation agility and collaborative innovation aspects. In addition, all the organisational model factors were supported and explained 46.5% of the variance in collaborative innovation internal outcomes and 53.2% of the variance in collaborative innovation external outcomes. However, personnel innovation acceptance made no significant effect on collaborative innovation outcomes.

<p>I studien har en relativt ovanlig intervjumetod, Repertory Grid Technology använts för att ge några blivande fysiklärares syn på god fysikundervisning. Metoden inspirerar till användning i många andra sammanhang. Resultaten visar att god fysikundervisning bland annat uppfattas som krävande för läraren.</p>

I studien har en relativt ovanlig intervjumetod, Repertory Grid Technology använts för att ge några blivande fysiklärares syn på god fysikundervisning. Metoden inspirerar till användning i många andra sammanhang. Resultaten visar att god fysikundervisning bland annat uppfattas som krävande för läraren.

Θέμα της παρούσας εργασίας είναι η υλοποίηση και εξομοίωση δίκαιων αλγόριθμων χρονοπρογραμματισμού σε Grids και η σύγκρισή τους με κλασικούς αλγόριθμους χρονοπρογραμματισμού. Η βασική ιδέα πίσω από την τεχνολογία Grid και τις υπηρεσίες που παρέχει είναι η ενοποίηση υπολογιστικών και αποθηκευτικών πόρων και η συνολική θεώρηση τους από τους χρήστες. Με τον τρόπο αυτό γίνεται δυνατή η ανάπτυξη πολύπλοκων και απαιτητικών εφαρμογών, τόσο στον χώρο της επιστημονικής έρευνας, όσο και στα πλαίσια της παραγωγής εμπορικών λύσεων. Ένα τέτοιο σύστημα απαιτεί διαμοιρασμό των υπολογιστικών και άλλων πόρων καθώς και μεγάλες ταχύτητες σύνδεσης μεταξύ τους. Οι αλγόριθμοι χρονοπρογραμματισμού αναλαμβάνουν τον αποδοτικό διαμοιρασμό των πόρων ώστε να επιτυγχάνεται καλύτερη ποιότητα υπηρεσίας. Η αποτελεσματικότητα ενός αλγόριθμου χρονοπρογραμματισμού εξαρτάται από την συνάρτηση που θέλουμε να βελτιστοποιήσουμε, που με τη σειρά της εξαρτάται από τεχνο-οικονομικά κριτήρια. Στην προσπάθεια βελτιστοποίησης της εκάστοτε συνάρτησης ευνοούνται κάποιες προς εκτέλεση διεργασίες έναντι άλλων. Ένας δίκαιος αλγόριθμος χρονοπρογραμματισμού όμως θα πρέπει να συμπεριφέρεται με τον ίδιο τρόπο σε όλες τις διεργασίες ανεξαρτήτως των χαρακτηριστικών τους. Στην εργασία που θα παρουσιάσουμε, αναλύουμε δύο δίκαιους αλγόριθμους χρονοπρογραμματισμού, τον Fair Completion Time (Ordering) και τον Fair Completion Time Estimation (Assignment). Κατόπιν τους υλοποιούμε και τους εξομοιώνουμε με το GridSim Toolkit και συγκρίνουμε την απόδοση τους με κλασικούς αλγόριθμους χρονοπρογραμματισμού. / The subject of this thesis is the implementation and simulation of fair scheduling algorithms applied on Computational Grids and their comparison with the classic scheduling algorithms. The basic idea of the Grid Technology and the services it provides, is the unification of computational and storage resources. This way it is possible to serve sophisticated applications, in fields like scientific research and trading. A Grid Network demands the sharing of the computational and storage resources, and high bandwidth connections between them. Scheduling algorithms are responsible for the efficient assignment of tasks to resources for better quality of service. Evaluating the efficiency of a scheduling algorithm depends on a utility function that we seek to optimize which in turns depends on techno-economic criteria. As a result of trying to optimize the utility function, some tasks with specific characteristics are favoured against others. A fair scheduling algorithm however should treat all tasks in the same way regardless of their characteristics. In this thesis we study the Fair Completion Time Ordering Algorithm and suggest a new fair scheduling algorithm called Fair Completion Time Estimation Assignment Algorithm. We implement and simulate these algorithms using the GridSim Toolkit and compare them with the classic scheduling algorithms.