The general aim of this research is to develop a conceptual privacy governance framework (CPGF) that can be used to develop a valid and reliable information privacy governance questionnaire (IPGQ) to assess the perception of employees of how effective the organisation governs privacy. The CPGF was developed to incorporate a comprehensive set of privacy components that could assist management in governing privacy across an organisation. IPGQ statements were derived from the theory of the sub-components of CPGF, evaluated by an expert panel and pre-tested by a pilot group. A quantitative mono method research was followed using a survey questionnaire to collect data in a financial institution in South Africa. Exploratory Factor Analysis (EFA) was used to determine the underlying factorial structure and the Cronbach Alpha was used to establish the internal reliability of the factors. From the initial item reduction of the constructs, four factors were derived to test the privacy perception of employees. The IPGQ consisted of 49 valid and reliable questions. One-way Analysis of Variance (ANOVA) was used, and three significant differences were discovered among the demographical groups for the age groups and two for the employment status groups (organisational commitment and privacy controls). The CPGF and IPGQ can aid organisations to determine if organisations are effectively governing the privacy in the organisations in order to assist them in meeting the accountability condition of the Protection of Personal Information Act (POPIA). / Computing / M. Sc. (Information Systems)

Die Forschungsarbeit beabsichtigte den Zusammenhang zwischen Kultur und der wahrgenommenen Bedienbarkeit der PIM Software seitens deutscher und indonesischer Anwender, welcher in zwei Experimenten untersucht wurde, zu erforschen. Die Entwicklung der PIM Technologie in beiden Ländern, sowie deren kultureller Wert, insbesondere Unsicherheitsvermeidung (UA) und Individualismus-Kollektivismus (INCOL), repräsentieren die zentralen Beweggründe der vorliegenden Untersuchung. Der betrachtete kulturelle Hintergrund und die verwendete Methodik stellen die Verbindung zwischen der ersten und zweiten Studie dar. Die Experimente waren in zwei Studien aufgeteilt, da jeder kulturelle Hintergrund ein unterschiedliches Erhebungsdesign benötigt: UA steht in Beziehung mit der ersten vs. der zweiten Aufgabe und INCOL wurde mittels zwei verschiedenen Wegen der Vervollständigung erfasst (Individual- vs. Gruppenaufgabe). Während sich der Fokus der ersten Studie auf den Vergleich zwischen der deutschen und indonesischen Kultur richtet, konzentrierte sich die zweite Studie auf Kulturen zwischen (Deutschland vs. Indonesien) und innerhalb eines Landes (Individualismus vs. Kollektivismus). Die Ergebnisse legen dar, dass deutsche Anwender ein höheres Level an Unsicherheitsvermeidung als indonesische Anwender zeigen. Lediglich hinsichtlich der Zufriedenheit weisen indonesische, verglichen zu deutschen Benutzern, einen höheren Wert auf, wobei der Haupteffekt der Zeit nur bezüglich der Höhe der Effizienz signifikant ist. Es zeigte sich außerdem ein positiver Zusammenhang zwischen UA und der Effizienz beider Aufgaben, sowie eine negative Korrelation zwischen UA und der berichteten Zufriedenheit. Hinsichtlich der Höhe von UA und der Effektivität ließ sich kein negativer Zusammenhang nachweisen. Desweiteren, betreffend INCOL, lässt sich zusammenfassen, dass der Hauptinteraktionseffekt Aufgabe*INCOL statistisch signifikant ist. Bezüglich Effizienz und Zufriedenheit ist entscheidend, dass, je höher die Ausprägung von Individualismus und Kollektivismus auf Seiten der Anwender ist, desto weniger Zeit beanspruchen diese für die Ausführung individueller Aufgaben und desto zufriedener wenden die Benutzer das PIM und GIM Tool an. Mit eingeschlossen ist jedoch, dass sich zwischen Individualismus und Kollektivismus deutscher und indonesischer Bediener kein Zusammenhang mit der Höhe der Effektivität darstellen lasst. Zusammenfassend ist festzuhalten, dass die Entwickler der PIM Software mit einer internationalen Anwendergruppe beachten sollten, dass die Ergebnisse von Usability Messungen seitens Benutzeranfänger in verschiedenen Kulturen unterschiedlich sein können.:1. Abstract 2. Chapter 1: Introduction 3. Chapter 2: Research Paradigm 4. Chapter 3: Uncertainty Avoidance and Usability of Personal Information Management 5. Chapter 4: Do Individualistic and Collective Persons Measure Usability of Personal and Group Information Management differently? A Culturability Study with German and Indonesian Users 6. Chapter 5: Summary and Conclusion 7. References

Introduction. The aim of this master thesis is to examine how students at Uppsala university manage, organize, and preserve their study-related information in a digital environment. It also investigates the motivations for personal information management (PIM) among students, and explores the concepts of sense making as both an activity and a desired outcome. The thesis focuses on the respondents’ experiences and behaviours in terms of PIM in relation to their digital collections.  Method. The research is based on 12 interviews with 9 exchange students, which were audio recorded and transcribed. Transcripts constituted the data for analysis.  Analysis. Interview data was analysed qualitatively with Nvivo software. Concepts were defined so that they could be used in the survey. Results. The study found that the five metalevels of PIM activities proposed by William Jones (2008) were applicable to the interview data, and that the respondents used a variety of digital tools and storage options, including cloud services, text editors and desktop applications, to organize and manage their information collections. Results are also presented in relation to Soo Jin Park’s (2011) three types of organizing and managing information collections.  Conclusion. The results showed that reflection on PIM and planning over time can lead to meaning-making and motivation for personal development. The degree of effort in organizing and managing information collections varied according to the individual values, personality, and contextual situations. The participants’ most common software for data storage were cloud services, text editors and web pages, with laptops, computers and mobile phones being the most popular devices for data storage. Some also had external hard drives as backup solutions and strict rules for discipline regarding PIM. While many participants trusted cloud storage when it came to privacy, some participants were skeptical of large IT companies and tried to find their own strategies to become less dependent on them. The majority made informed choices due to the risk of data loss and fragmentation. They had a profile of cognitive skills that included the ability to use visual messages to create unification and transparency in systems. They had a mix of dynamic and large collections of data.  They preferred to structure their files in a specific and structured system. Some preferred to file in more well-defined locations, while others used a more flexible method of organization. The majority had a one folder filing strategy. Some had file systems with a top-down approach, while others used incremental bottom-up strategies. They used a variety of PIM tools and strategies to meet their changing needs, such as using descriptive file names, splitting projects into smaller collections, regularly reviewing and deleting older files and categorize files by date. The study provided valuable insights into the process of managing digital information and the importance of continuous evaluation and adaptation of PIM tools and strategies to meet the changing needs of participants.  This is a two years master’s thesis in Archival Science.

Social media become a powerful communication medium for effective online social interaction globally. The use of various social networking sites has integrated into people’s daily lives especially among young adults. Problem arises when personal information is used without individuals’ involvement and relevant privacy risks increased. The main focus for the thesis is to investigate privacy perception and risks knowledge of Facebook usage among university students in Sweden. Based on this focus, the research identifies the key reasons that students decide to use and still use Facebook despite of privacy risks. The study also explores how user perspective of privacy affects the utilization of Facebook. The adopted methodology is qualitative research through the methods of interview and Facebook data analysis among ten young adult students at Linnaeus University in Sweden. As result, the research has identified seven concepts and three special outcomes to answer the research questions. Through the analysis, we have recognized weak perception of privacy risks among university students. Although users claim they are privacy concerned yet large amount of private information is shared on Facebook. The findings have shown that users are somewhat willing to accept certain part of potential privacy risks and personal information usage by different parties, in exchange for benefits and needs of online interaction in today’s modern society. Users believe the shared personal information on Facebook is under control and they can prepare for possible consequences. However, we believe that people’s needs for popular online social interaction outweigh privacy concerns. We suggest that it is significantly important for social networking sites’ users to balance benefits and risks, in order to maintain balanced usage and positive effects of online personal privacy. In the end of the thesis, we have suggested two future research directions based on our research topic.

The sharing of personal information among health and social service organisations is a complex issue and problematic process in present-day England. Organisations which provide services to children face enormous challenges on many fronts. Internal ways of working, evolving best practice, data protection applications, government mandates and new government agencies, rapid changes in technology, and increasing costs are but a few of the challenges with which organisations must contend in order to provide services to children while keeping in step with change. This thesis is an exploration into the process of sharing personal information in the context of public sector reforms. Because there is an increasing emphasis of multi-agency collaboration, this thesis examines the information sharing processes both within and among organisations, particularly those providing services to children. From the broad principles which comprise a socio-technical approach of information sharing, distinct critical factors for successful information sharing and best practices are identified. These critical success factors are then used to evaluate the emerging national database, ContactPoint, highlighting particular areas of concern. In addition, data protection and related issues in the information sharing process are addressed. It is argued that one of the main factors which would support effective information sharing is to add a timeline to the life of a dataset containing personal information, after which the shared information would dissolve. Therefore, this thesis introduces Dynamic Multi-Agency Collaboration (DMAC), a theoretical model of effective information sharing using a limited-life dataset. The limited life of the DMAC dataset gives more control to information providers, encouraging effective information sharing within the parameters of the Data Protection Act 1998.

Cette thèse a été réalisée dans le cadre du projet PIMI, financé par l’Agence Nationale de la Recherche. Elle porte sur la modélisation et l’utilisation d’informations personnelles dont la validité ou l'utilisabilité dépend du contexte. Plus particulièrement, elle a pour but d'aider l’utilisateur à réaliser des procédures en ligne. Elle aborde les problématiques de la représentation d’informations hétérogènes,d’interrogation d’espaces d’informations personnelles contextualisées, de remplissage automatique de formulaires et de réalisation automatique de procédures définies à un haut niveau d’abstraction par composition de services disponibles en ligne. Pour répondre à ces problématiques, nous avons proposé plusieurs contributions.La première contribution porte sur la gestion d’un espace d’informations personnelles. Nous avons proposé une modélisation permettant la description des informations personnelles en utilisant plusieurs ontologies de domaine. Ces informations personnelles sont ainsi instanciées avec différentes valeurs dont l’utilisabilité dépend du contexte et d'un degré d'utilisabilité. Nous avons également proposé deux algorithmes d’interrogation contextuelles SQE et FQE qui permettent la recherche par des requêtes sur des informations personnelles stockées.La seconde contribution porte sur l'utilisation de ces informations par de différents services en ligne, et ce dans deux cas. Dans le cas du remplissage automatique de formulaires, nous avons proposé un algorithme permettant de générer une requête sémantique à partir de la représentation annotée d’un formulaire. Cette requête est évaluée en utilisant les deux algorithmes d'interrogation SQE et FQE. Dans le cas de la réalisation d'un objectif utilisateur par composition de services, nous avons étendu l'algorithme de Graphplan pour prendre en compte la contextualisation des données et des politiques de sécurité spécifiées par l'utilisateur. Ces dernières permettent ainsi à l'utilisateur d'augmenter le contrôle sur ses informations et de limiter leur divulgation. / This thesis was conducted within the PIMI project, financed by the National Agency of the Research. It concerns the modeling, the querying and thecomposition of personal information. We considered that the use and the accessto personal information is context dependent (e.g., social, geographical). More particularly, it aims to support the user when realising online,administrative or personal procedures. In this setting, the tackled problems arethe representation of heterogeneous information, the context-aware personalinformation spaces querying, the automatic form-filling and the automaticrealization of procedures defined at a high level of abstraction by compositionof online available services.To solve these problems, we have developped several contributions. The first oneconcerns the management of the personal information space. We havedefined a model allowing the description of personal information using severaldomain ontologies. Our model can be instantiated on the user's personalinformation with several usability values depending on the context and with ausability degree. We have also proposed two contextualquerying algorithms SQE and FQE which allow to query the recorded information.The second contribution concerns the use of these information by several onlineservices. It presents two use cases. In the case of the automaticforms-filling, we have proposed an algorithm allowing to generate a semanticquery from an annotated form representation. This query is evaluated by usingboth querying algorithms SQE and FQE. Then, in the case of the user objectiverealization (an abstract procedure) by service composition, we have extendedthe Graphplan algorithm to take into account the contextualization of the dataand the access policy rules specified by the user. The latter allows the user toincrease the control of its information and to limit their leaking.

Os arquivos pessoais possuem seu tratamento e preservação justificados pelo valor histórico, cultural e testemunhal que assumem a respeito das personalidades que os acumularam; por essa razão, devem ser (re)considerados nos campos da Ciência da Informação e, especialmente, da Arquivologia. Devido aos limiares, sobretudo da informalidade e da subjetividade, refletidos em seus documentos, esses acervos foram, diacronicamente, contemplados aquém do arcabouço teórico e metodológico dos referidos domínios e de seus processos. Por conseguinte, o tratamento da informação a eles conferido se deu por preceitos, princípios e métodos desalinhados ao que denominamos, nesta investigação, \"racionalização arquivística\", abordagem baseada no respect des fonds (e seus desdobramentos), pela qual os arquivos pessoais passam, pois, a ser concebidos enquanto tais: arquivos, conjuntos de documentos orgânicos cuja procedência são pessoas (físicas). Na Diplomática Clássica, pouco provavelmente os registros particulares seriam passíveis de análise e crítica; todavia, uma vez revisitada pela Arquivologia, assume um caráter, apesar de também crítico, voltado à terminologia e à funcionalidade, para além da formalidade, da qual são esses documentos, comum e facultativamente, desprovidos. Nesse sentido, a metodologia passa a se ocupar da verificação dos contextos de produção e das atividades, mandatórias ou espontâneas, que dão origem aos documentos, em perspectiva contextual. Dessa premissa, temos por objetivo geral a proposta de refletir acerca da contextualização da informação em arquivos pessoais, bem como seus limiares, no domínio da Arquivologia, por meio da práxis da identificação de tipologia documental no fundo Clarice Lispector, custodiado pelo Arquivo-Museu de Literatura Brasileira. Trata-se de uma pesquisa qualitativa e exploratória, pautada em levantamento bibliográfico e documental, e no estudo de caso do arquivo da modernista. Nesta, foram, pois, identificados e relacionados os tipos documentais que compõem as seis séries de gênero textual do vigente quadro de arranjo do arquivo Clarice. Almejamos, ao final, evidenciar a relevância do \"percurso diplomático\" (à identificação arquivística) como parâmetro de contextualização desses acervos, bem como revisão e perspectivas de organização de sua informação. / The personal archives have their management and presentation justified by the historical, cultural e testimonial value regarding the personalities who have accumulated them; thus, they are out to be (re)considered within the fields of Information and, specially, Archival Science. Due to the challenges, withal informality and subjectivity reflected on their documents, such collections have, diachronically, been contemplated short from the theoretical and methodological framework development of the referred domains and their processes. As a result, the information treatment given out to them occurred through precepts, principles and methods misaligned with what we have denominated, in this investigation, \"archival rationalization\", a respect des fonds (and its outspreads) based approach, through which personal archives and then conceived as such: archives, collection of organic documents whose provenance are people. In the classical theory of Diplomatic, the personal archive documents would unlikely be subject to analysis and criticism; however, once revisited by Archival Science, it assumes a character, despite also critical, focused on terminology and functionality, beyond formality, of which they are common and facultatively devoid. In this sense, such methodology tends to be concerned about verifying the contexts of production and the mandatory or spontaneous activities that pin down documents, under contextual perspective. From this premise, our general objective is the proposal to reflect about the contextualization of information in personal archives, as well as their thresholds in the Archival Science domain, through the praxis of documental typology identification in Clarice Lispector\'s private archive, held by the Brazilian Literature Archive-Museum. It is a qualitative and exploratory research, based on bibliographical and documental survey, as well as on the modernist writer\'s case study. In this were identified and reported the documental types which make up the six textual-genre series of Clarice\'s archive\'s current arrangement scheme. We aim to evidence the relevance of the \"diplomatic route\" (to archival identification) as a parameter of contextualization of such archives, and also as a review and perspectives of organization of their information.

In order to improve the quality of care, there is urgent need to involve patients in their own healthcare. So to make patient centered health care system Personal Health Records are proposed as viable solution. This research discusses the importance of a Patient Centric Health Record system. Such systems can empower patients to participate in improving health care quality. It would also provide an economically viable solution to the need for better healthcare without escalating costs by avoiding duplication. The proposed system is Web-based; therefore it has high accessibility and availability. The cloud computing based architecture is used which will allow consumers to address the challenge of sharing medical data. PHR would provide a complete and accurate summary of the health and medical history of an individual by gathering data from many sources. This would make information accessible online to anyone who has the necessary electronic credentials to view the information. / by Vishesh Ved. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Personal document management is the activity of managing a collection of digital documents performed by the owner of the documents, and consists of creation/acquisition, organisation, finding and maintenance. Document management is a pervasive aspect of digital work, but has received relatively little attention from researchers. The hierarchical file system used by most people to manage their documents has not conceptually changed in decades. Although revolutionary prototypes have been developed, these have not been grounded in a thorough understanding of document management behaviour and therefore have not resulted in significant changes to document management interfaces. Improvements in understanding document management can result in productivity gains for knowledge workers, and since document management is such a common activity, small improvements can deliver large gains. The aim of this research was to understand how people manage their personal document collections and to develop guidelines for the development of tools to support personal document management. A field study was conducted that included interviews, a survey and file system snapshot. The interviews were conducted with ten participants to investigate their document management strategies, structures and struggles. In addition to qualitative analysis of semi-structured interviews, a novel investigation technique was developed in the form of a file system snapshot which collects information about document structures and derives a number of metrics which describe the document structure. A survey was also conducted, consisting of a questionnaire and a file system snapshot, which enabled the findings of the field study to be validated, and to collect information from a greater number of participants. The results of this research culminated in (1) development of a conceptual framework highlighting the key personal document management attitudes, behaviours and concerns; (2) model of basic operations that any document management system needs to provide; (3) identification of piling, filing and structuring as three key document management strategies; (4) guidelines for the development of user interfaces to support document management, including specific guidelines for each document management strategy. These contributions both improve knowledge of personal document management on which future research can build, and provide practical advice to document management system designers which should result in the development of more usable system.

Οι τεχνολογικές εξελίξεις των τελευταίων ετών, έχουν αναβαθμίσει τις κινητές συσκευές, από απλά κινητά τηλέφωνα σε συσκευές κινητού υπολογισμού. Οι σύγχρονες κινητές συσκευές είναι πλέον εξοπλισμένες με φωτογραφικούς φακούς υψηλής ανάλυσης, δέκτη GPS, δέκτη WiFi (802.11 b/g/n), κυκλώματα NFC, δυνατότητες σύνδεσης στο διαδίκτυο μέσω δικτύων κινητής τηλεφωνίας (3G/4G), επιταχυνσιόμετρα, αισθητήρες καταγραφής καρδιακών παλμών κ.α. Οι αισθητήρες αυτοί, είναι σε θέση να συλλέγουν πληροφορίες για το πλαίσιο του χρήστη (user’s context), το οποίο συμπεριλαμβάνει πληροφορίες όπως η τοποθεσία του, η τρέχουσα μέρα και ώρα, ο προσανατολισμός της συσκευής, το αν ο χρήστης κινείται και με πόση ταχύτητα, την τρέχουσα δραστηριότητα του χρήστη (π.χ. ομιλία, πληκτρολόγηση κειμένου) κ.α. Επίσης, οι ίδιοι οι χρήστες αποθηκεύουν στις συσκευές όλο και περισσότερες προσωπικές πληροφορίες, όπως το ιστορικό της επικοινωνίας τους, σύντομα μηνύματα, φωτογραφίες, emails, μουσική και βίντεο, υπενθυμίσεις και γεγονότα στο ημερολόγιο κ.α. Ο συνδυασμός του πλαισίου του χρήστη με την κοινωνική πληροφορία του χρήστη, δημιουργούν ένα δυναμικά οριζόμενο πλαίσιο, το κοινωνικό κινητό πλαίσιο του χρήστη (user’s mobile social context). Σκοπός της διδακτορικής διατριβής, είναι η υποστήριξη του χρήστη για την ανάκτηση προσωπικών πληροφοριών από συσκευές κινητού υπολογισμού, με αξιοποίηση του κινητού κοινωνικού πλαισίου. Στα πλαίσια της διδακτορικής διατριβής, ως περίπτωση χρήσης, μελετήθηκε η ανάκτηση επαφών από το χρήστη με σκοπό την επικοινωνία (κλήση, μήνυμα κ.λπ.). Παρόλα αυτά, η μεθοδολογία που ακολουθήθηκε μπορεί να εφαρμοστεί για την ανάκτηση οποιουδήποτε είδους προσωπικής πληροφορίας, όπως φωτογραφίες, βίντεο, μουσική κ.α. Συγκεκριμένα, αφού μελετήθηκαν πραγματικά δεδομένα χρήσης από δύο σύνολα δεδομένων, σχεδιάστηκε και υλοποιήθηκε ένας νέος αλγόριθμος για την πρόβλεψη της μελλοντικής επικοινωνίας του χρήστη συσκευών κινητού υπολογισμού. Στη συνέχεια, έγινε σύγκριση του συγκεκριμένου αλγορίθμου με υπάρχουσες προσεγγίσεις, οι οποίες αναφέρονται στη βιβλιογραφία. Κατόπιν, σχεδιάστηκε και υλοποιήθηκε σύστημα για συσκευές κινητού υπολογισμού το οποίο ενσωματώνει τον προτεινόμενο αλγόριθμο. Παράλληλα, σχεδιάστηκαν, υλοποιήθηκαν και αξιολογήθηκαν, τόσο στο εργαστήριο όσο και με πειράματα πεδίου, υβριδικές προσαρμοστικές διεπαφές για την παρουσίαση των προτάσεων του αλγορίθμου και, γενικότερα, την υποστήριξη ανάκτησης προσωπικής πληροφορίας, όπως οι επαφές, σε συσκευές κινητού υπολογισμού. Αναλυτικότερα, στο πρώτο κεφάλαιο, παρουσιάζεται η τρέχουσα κατάσταση στο πεδίο των συσκευών κινητού υπολογισμού, σε επίπεδο υλικού, σε επίπεδο δικτύων και σε επίπεδο λειτουργικών συστημάτων των συσκευών κινητού υπολογισμού. Επίσης, παρουσιάζεται συνοπτικά η έννοια του context και των context aware συστημάτων. Τέλος, γίνεται μια πρώτη καταγραφή των ερευνητικών θεμάτων της διδακτορικής διατριβής και παρουσιάζεται συνοπτικά η συνεισφορά της. Στο δεύτερο κεφάλαιο, γίνεται μια εκτενής παρουσίαση της τρέχουσας ερευνητικής δραστηριότητας στον τομέα της διδακτορικής διατριβής. Συγκεκριμένα, αναπτύσσονται οι έννοιες του context και των context-aware συστημάτων και στη συνέχεια γίνεται αναφορά στις έννοιες του mobile και social context. Κατόπιν, παρουσιάζονται μεθοδολογίες ανάκτησης και μοντελοποίησης του context, με έμφαση στο context των συσκευών κινητού και διάχυτου υπολογισμού. Στη συνέχεια, παρουσιάζονται χαρακτηριστικά παραδείγματα κινητών context aware συστημάτων, με έμφαση στα context aware συστήματα για τη διαχείριση προσωπικής πληροφορίας σε συσκευές κινητού υπολογισμού και ειδικότερα στη διαχείριση των επαφών και της επικοινωνίας του χρήστη. Τέλος, παρουσιάζονται νέα είδη διεπαφών (adaptive interfaces), οι οποίες προσαρμόζονται στο τρέχον context της συσκευής κινητού υπολογισμού. Στο τρίτο κεφάλαιο, παρουσιάζεται το πρώτο μέρος του ερευνητικού έργου της παρούσας διδακτορική διατριβής. Συγκεκριμένα, παρουσιάζεται η μελέτη και υλοποίηση ενός αλγορίθμου για την ανάκτηση προσωπικής πληροφορίας από συσκευές κινητού υπολογισμού. Ως περίπτωση χρήσης, εστιάσαμε στην ανάκτηση των επαφών. Αρχικά, παρουσιάστηκε ο τρόπος με τον οποίο επιλέξαμε να αναπαραστήσουμε το context του χρήστη. Στη συνέχεια, για να ερευνηθεί ποιες διαστάσεις του context είναι οι σημαντικότερες για την ανάκτηση επαφών, πραγματοποιήθηκε η ανάλυση δύο συνόλων δεδομένων, ενός που συλλέχθηκε στα πλαίσια της διδακτορικής διατριβής και ενός που παραχωρήθηκε από την εταιρία ΝΟΚΙΑ. Κατόπιν, παρουσιάζεται ο σχεδιασμός και η πειραματική αξιολόγηση του αλγορίθμου. Τέλος, παρουσιάζεται η σύγκριση του προτεινόμενου αλγορίθμου με αντίστοιχους αλγορίθμους και προσεγγίσεις της βιβλιογραφίας. Στο τέταρτο κεφάλαιο, παρουσιάζεται η υλοποίηση ενός συστήματος ανάκτησης επαφών σε συσκευές κινητού υπολογισμού. Συγκεκριμένα, υλοποιήθηκε ο αλγόριθμος που παρουσιάστηκε στο προηγούμενο κεφάλαιο και στη συνέχεια σχεδιάστηκαν και υλοποιήθηκαν context aware προσαρμοστικές διεπαφές, για την ανάκτηση επαφών σε συσκευές κινητού υπολογισμού. Στη συνέχεια, παρουσιάζεται η αξιολόγηση του συστήματος που υλοποιήθηκε, με την πραγματοποίηση πειράματος πεδίου, διάρκειας ενός μήνα. Κατά τη διάρκεια του πειράματος, συλλέγονταν ανώνυμα στατιστικά χρήσης του συστήματος, ενώ, στο τέλος του πειράματος, έγινε και συλλογή ποιοτικών δεδομένων, με χρήση ερωτηματολογίων. Στο τελευταίο, πέμπτο, κεφάλαιο, παρουσιάζεται μία σύνοψη της διδακτορικής διατριβής, καταγράφονται τα συμπεράσματα της και γίνεται αναφορά στις μελλοντικές επεκτάσεις του ερευνητικού έργου. / Recent technological advances have transformed the mobile phones from simple communication devices to pervasive computing devices. Today’s mobiles are equipped with a great variety of hardware, such as high definition cameras, GPS receivers, WiFi capabilities, NFC chips, 3G/4G mobile network connections, compass, accelerometers etc. Those sensors collect a huge amount of information about mobile device’s user and her environment (user’s context), for example, the location, current day and time, device’s orientation, if she is on the move and how fast, the current task (e.g. talking, typing text) etc. Besides the automatically generated information, users keep a lot of personal information on their mobile devices like communication history, short messages, photos, emails, music and videos, reminder and calendar events etc. If we combine the user’s context with the stored social information, a dynamic context is created, which can be termed the user’s mobile social context. The aim of this PhD thesis is the exploitation of user’s mobile social context in order to support the extraction of personal information from mobile computing devices. As an example of personal information, this thesis studies the support of user’s communication by extracting the desired contacts. However, the same methodology applies to all kinds of personal information like photos, videos, music etc. First of all, real mobile usage statistics from two different datasets were analyzed in order to design and implement a new prediction algorithm of the future user’s communication on mobile devices. Secondly, a comparison between the proposed algorithm and relative algorithms was conducted. Then, a system for mobile devices that embeds the proposed algorithm was developed. At the same time, adaptive interfaces for the presentation of the proposals of the algorithm were designed and evaluated, conducting both lab and field experiments. Chapter 1 presents the current status in the field of mobile computing devices, in terms of hardware, mobile networks and mobile operating systems. The terms “context” and “context aware” systems are also briefly presented. Finally, Chapter 1 presents the research question of this thesis and its research contribution. Chapter 2 presents the related work in the field. First, the terms “context” and “context aware” are discussed in detail and then the terms of “mobile” and “social context” are introduced. The chapter discusses proposals for retrieving and modeling the user’s context, giving detailed information about the mobile user’s context. Also, in the same chapter, examples of context aware systems are presented, focusing mainly to context aware systems for communication management and contacts retrieval. Finally, novel, adaptive, context aware interfaces are also presented. Chapter 3 presents the first part of the thesis’ research. A new algorithm for the task of contacts retrieval is proposed. In order to choose the proper dimensions of the user’s context for the specific task, an analysis and examination of two different dataset is perfomed. The first dataset is preliminary and it is collected in the context of this thesis. The second one is provided by NOKIA and is the outcome of a large scale initiative that took place in Geneva area of Switzerland, the NOKIA Lausanne Data Collection Campaign. A comparative evaluation of the proposed algorithm against the two mentioned datasets is finally performed. Finally, a comparison of the proposed algorithm with similar approaches and algorithms is presented. In Chapter 4, the design and implementation of a Google Android system for contacts retrieval from mobile computing devices is presented. A set of context aware adaptive interfaces for contacts retrieval was designed and developed, to make use of the algorithm discussed in Chapter 3. These interfaces were tested using a large scale field experiment (1 month duration) in order to evaluate the system in real conditions and with real users. During the experiment, anonymous usage statistics from users were collected and a questionnaire for the qualitative evaluation of our system was also distributed. In the final chapter (chapter 5), the conclusions of the thesis and future work suggestions are presented.