Doctor of Philosophy(PhD) / Digital photography has not only changed the nature of photography and the photographic process, but also the manner in which we share photographs and tell stories about them. Some traditional methods, such as the family photo album or passing around piles of recently developed snapshots, are lost to us without requiring the digital photos to be printed. The current, purely digital, methods of sharing do not provide the same experience as printed photographs, and they do not provide effective face-to-face social interaction around photographs, as experienced during storytelling. Research has found that people are often dissatisfied with sharing photographs in digital form. The recent emergence of the tabletop interface as a viable multi-user direct-touch interactive large horizontal display has provided the hardware that has the potential to improve our collocated activities such as digital photograph sharing. However, while some software to communicate with various tabletop hardware technologies exists, software aspects of tabletop user interfaces are still at an early stage and require careful consideration in order to provide an effective, multi-user immersive interface that arbitrates the social interaction between users, without the necessary computer-human interaction interfering with the social dialogue. This thesis presents PhoTable, a social interface allowing people to effectively share, and tell stories about, recently taken, unsorted digital photographs around an interactive tabletop. In addition, the computer-arbitrated digital interaction allows PhoTable to capture the stories told, and associate them as audio metadata to the appropriate photographs. By leveraging the tabletop interface and providing a highly usable and natural interaction we can enable users to become immersed in their social interaction, telling stories about their photographs, and allow the computer interaction to occur as a side-effect of the social interaction. Correlating the computer interaction with the corresponding audio allows PhoTable to annotate an automatically created digital photo album with audible stories, which may then be archived. These stories remain useful for future sharing -- both collocated sharing and remote (e.g. via the Internet) -- and also provide a personal memento both of the event depicted in the photograph (e.g. as a reminder) and of the enjoyable photo sharing experience at the tabletop. To provide the necessary software to realise an interface such as PhoTable, this thesis explored the development of Cruiser: an efficient, extensible and reusable software framework for developing tabletop applications. Cruiser contributes a set of programming libraries and the necessary application framework to facilitate the rapid and highly flexible development of new tabletop applications. It uses a plugin architecture that encourages code reuse, stability and easy experimentation, and leverages the dedicated computer graphics hardware and multi-core processors of modern consumer-level systems to provide a responsive and immersive interactive tabletop user interface that is agnostic to the tabletop hardware and operating platform, using efficient, native cross-platform code. Cruiser's flexibility has allowed a variety of novel interactive tabletop applications to be explored by other researchers using the framework, in addition to PhoTable. To evaluate Cruiser and PhoTable, this thesis follows recommended practices for systems evaluation. The design rationale is framed within the above scenario and vision which we explore further, and the resulting design is critically analysed based on user studies, heuristic evaluation and a reflection on how it evolved over time. The effectiveness of Cruiser was evaluated in terms of its ability to realise PhoTable, use of it by others to explore many new tabletop applications, and an analysis of performance and resource usage. Usability, learnability and effectiveness of PhoTable was assessed on three levels: careful usability evaluations of elements of the interface; informal observations of usability when Cruiser was available to the public in several exhibitions and demonstrations; and a final evaluation of PhoTable in use for storytelling, where this had the side effect of creating a digital photo album, consisting of the photographs users interacted with on the table and associated audio annotations which PhoTable automatically extracted from the interaction. We conclude that our approach to design has resulted in an effective framework for creating new tabletop interfaces. The parallel goal of exploring the potential for tabletop interaction as a new way to share digital photographs was realised in PhoTable. It is able to support the envisaged goal of an effective interface for telling stories about one's photos. As a serendipitous side-effect, PhoTable was effective in the automatic capture of the stories about individual photographs for future reminiscence and sharing. This work provides foundations for future work in creating new ways to interact at a tabletop and to the ways to capture personal stories around digital photographs for sharing and long-term preservation.

Offshore software development (OSD) is a leading business sector in the present ‘glocal’ IT marketplace, and vendors in different countries are opening software development centres worldwide to take advantage of the new business opportunities. However, software development is both a technical and a social process as various software modules need to be integrated, which requires ongoing interaction between the stakeholders. The software modules rely upon local knowledge regarding customer wants, project specific features, chosen design methodologies by development team members and synchronisation of activities to confirm the next design iteration. This study focuses on knowledge sharing processes involving the interplay between acquiring local knowledge and applying the knowledge acquired into the design of the client-specific software builds. New knowledge is created as new processes are applied and new outcomes realised, resulting in re-definition of software development practices. Building on existing theories with empirical case study evidence, this research reveals the socio-technical influences on knowledge management in the OSD process. Ideographic research methods have been applied to bring sensitivity in the everyday organisational activities for knowledge sharing across diverse social and cultural groups within two country contexts (New Zealand and India). Empirical data from ten case studies is used to inductively develop a conceptual framework, which has been applied to make within case and cross case comparisons across three levels of analysis (micro, meso and macro) for knowledge sharing. The micro level analysis explores individual key success drivers (behaviours and methodologies), the meso level explores organisational level practices (work processes and structures) and the macro level gives a holistic evaluation across two country contexts. Country contexts reveal that New Zealand vendors share closer cultural proximity with their clients, are engaged in client facing skills and have further outsourced software development tasks to other low cost countries. The Indian vendors are involved in software construction, prefer technical specialist skills and have defined more discipline in their software development processes. The thesis offers new insights on how vendors’ shape their software development styles based upon their beliefs and understanding of the offshore market and is especially relevant to both vendors and clients who intend venturing into the offshore market.

Introducing function sharing into designs allows eliminating costly structure by adapting existing structure to perform its function. This can eliminate many inefficiencies of reusing general componentssin specific contexts. "Redistribution of intermediate results'' focuses on instances where adaptation requires only addition/deletion of data flow and unused code removal. I show that this approach unifies and extends several well-known optimization classes. The system performs search and screening by deriving, using a novel explanation-based generalization technique, operational filtering predicates from input teleological information. The key advantage is to focus the system's effort on optimizations that are easier to prove safe.

Secret sharing is a fundamental notion for secure cryptographic design. In a secret sharing scheme, a set of participants shares a secret among them such that only pre-specified subsets of these shares can get together to recover the secret. This dissertation introduces a neural network approach to solve the problem of secret sharing for any given access structure. Other approaches have been used to solve this problem. However, the yet known approaches result in exponential increase in the amount of data that every participant need to keep. This amount is measured by the secret sharing scheme information rate. This work is intended to solve the problem with better information rate.

This thesis focuses on the industry wage differentials, rent-sharing and the gender wage gap. I empirically investigate: i) the interaction between inter-industry wage differentials and the gender wage gap in six European countries, ii) how rent sharing interacts with the gender wage gap in the Belgian private sector and iii) the existence of inter-industry wage differentials in Belgium, through the unobserved ability hypothesis. The first chapter is devoted to the analysis of the interaction between inter-industry wage differentials and the gender wage gap in six European countries, i.e. Belgium, Denmark, Ireland, Italy, Spain, and the U.K. To do so, we have relied on a unique harmonised matched employer-employee data set, the 1995 European Structure of Earnings Survey. As far as we know, this paper is the first to analyse with recent techniques, on a comparable basis, and from a European perspective: i) inter-industry wage differentials by gender, ii) gender wage gaps by industry, and iii) the contribution of industry effects to the overall gender wage gap. It is also one of the few, besides Kahn (1998), to analyse for both sexes the relationship between collective bargaining characteristics and the dispersion of industry wage differentials. Empirical findings show that, in all countries and for both sexes, wage differentials exist between workers employed in different sectors, even when controlling for working conditions, individual and firm characteristics. We also find that the hierarchy of sectors in terms of wages is quite similar for male and female workers and across countries. Yet, the apparent similarity between male and female industry wage differentials is challenged by standard statistical tests. Indeed, simple t-tests show that between 43 and 71% of the industry wage disparities are significantly different for women and men. Moreover, Chow tests indicate that sectoral wage differentials are significantly different as a group for both sexes in all countries. Regarding the dispersion of the industry wage differentials, we find that results vary for men and women, although not systematically nor substantially. Yet, the dispersion of industry wage differentials fluctuates considerably across countries. It is quite large in Ireland, Italy and the U.K., and relatively moderate in Belgium, Denmark and Spain. For both sexes, results point to the existence of a negative and significant relationship between the degree of centralisation of collective bargaining and the dispersion of industry wage differentials. Furthermore, independently of the country considered, results show that more than 80% of the gender wage gaps within industries are statistically significant. The average industry gender wage gap ranges between -.18 in the U.K. and -.11 in Belgium. This means that on average women have an inter-industry wage differential of between 18 and 11% below that for men. Yet, correlation coefficients between the industry gender wage gaps across countries are relatively small and often statistically insignificant. This finding suggests that industries with the highest and the lowest gender wage gaps vary substantially across Europe. Finally, results indicate that the overall gender wage gap, measured as the difference between the mean log wages of male and female workers, fluctuates between .18 in Denmark and .39 in the U.K. In all countries a significant (at the .01 level) part of this gap can be explained by the segregation of women in lower paying industries. Yet, the relative contribution of this factor to the gender wage gap varies substantially among European countries. It is close to zero in Belgium and Denmark, between 7 and 8% in Ireland, Spain and the U.K., and around 16% in Italy. Differences in industry wage premia for male and female workers significantly (at the .05 level) affect the gender wage gap in Denmark and Ireland only. In these countries, gender differences in industry wage differentials account for respectively 14 and 20% of the gender wage gap. To sum up, findings show that combined industry effects explain around 29% of the gender wage gap in Ireland, respectively 14 and 16% in Denmark and Italy, around 7% in the U.K. and almost nothing in Belgium and Spain. In conclusion, our results emphasize that the magnitude of the gender wage gap as well as its causes vary substantially among the European countries. This suggests that no single policy instrument will be sufficient to tackle gender pay inequalities in Europe. Our findings indicate that policies need to be tailored to the very specific context of the labour market in each country. The second chapter examines investigates how rent sharing interacts with the gender wage gap in the Belgian private sector. Empirical findings show that individual gross hourly wages are significantly and positively related to firm profits-per-employee even when controlling for group effects in the residuals, individual and firm characteristics, industry wage differentials and endogeneity of profits. Our instrumented wage-profit elasticity is of the magnitude 0.06 and it is not significantly different for men and women. Of the overall gender wage gap (on average women earn 23.7% less than men), results show that around 14% can be explained by the fact that on average women are employed in firms where profits-per-employee are lower. Thus, findings suggest that a substantial part of the gender wage gap is attributable to the segregation of women is less profitable firms. The third and final chapter contributes to the understanding of inter-industry wage differentials in Belgium, taking advantage of access to a unique matched employer-employee data set covering the period 1995-2002. Findings show the existence of large and persistent wage differentials among workers with the same observed characteristics and working conditions, employed in different sectors. The unobserved ability hypothesis may not be rejected on the basis of Martins’ (2004) methodology. However, its contribution to the observed industry wage differentials appears to be limited. Further results show that ceteris paribus workers earn significantly higher wages when employed in more profitable firms. The instrumented wage-profit elasticity stands at 0.063. This rent-sharing phenomenon accounts for a large fraction of the industry wage differentials. We find indeed that the magnitude, dispersion and significance of industry wage differentials decreases sharply when controlling for profits.

Multiparty computation is a computation between multiple players which want to compute a common function based on private input. It was first proposed over 20 years ago and has since matured into a well established science. The goal of this thesis has been to develop efficient protocols for different operations used in multiparty computation and to propose uses for multiparty computation in real world systems. This thesis therefore gives the reader an overview of multiparty computation from the simplest primitives to the current state of software frameworks for multiparty computation, and provides ideas for future applications. Included in this thesis is a proposed model of multiparty computation based on a model of communication complexity. This model provides a good foundation for the included papers and for measuring the efficiency of multiparty computation protocols. In addition to this model, a more practical approach is also included, which examines different secret sharing schemes and how they are used as building blocks for basic multiparty computation operations. This thesis identifies five basic multiparty computation operations: sharing, recombining, addition, multiplication and negation, and shows how these five operations can be used to create more complex operations. In particular two operations “less-than” and “bitwise decomposition” are examined in detail in the included papers. “less-than” performs the “<” operator on two secret shared values with a secret shared result and “bitwise decomposition” takes a secret shared value and transforms it into a vector of secret shared bitwise values. The overall goal of this thesis has been to create efficient methods for multiparty computation so that it might be used for practical applications in the future.

No description available.

As more and more convenience technology brings to human’s life by breaking through the obstacles of geography and psychology, e-health is being accepted by increasing number of people. It shows great potential to decrease the gap between the needs and satisfaction. However, the potential of e-health is far from being noticed. Knowledge shows inevitable advantages in different domains and of course the same in the health care industry. There are many different aspects that can be investigated and improved to reach the purpose, but in this dissertation, we aims to explore how to achieve a better knowledge transfer and sharing among e-health service-providers in order to create high-quality services that will be delivered to the patients. In general, U-CARE community is the one case that studied in this dissertation to explore how to identify knowledge transfer & sharing practices and what techniques can be used to improve it in the context of e-health. A theoretical framework from Etienne Wenger is applied here to help the author understand community well. Further analysis and discussion are based both on existing theories derived from literature review and empirical data obtained in interviews. The main contribution from the author and conclusion in this dissertation are summarized in a format of framework concerning useful techniques and methods (shown in Figure 9), which involves knowledge transfer and sharing practices related to formal/informal meetings, face-to-face communication, coordinator, online platform, IT tools, change management, documentation management, tracking of requirements & decisions, library of FAQ and personalization. The transferred and shared knowledge investigated in this dissertation is “back-office” data, not directly related to patient data, so the protection of patient personal privacy is not a consideration in this dissertation.

In most of the fields, manufacturers are continuously pushed by the market to provide turnkey solutions to the clients. This phenomenon is especially appearing in recycled water projects since the water treatment technology is very specific and complicated to operate. To understand this trend, a real case study is conducted in Veolia Water Solutions & Technologies (VWS) in Australia. This thesis analyses the main reasons for VWS to propose Product/Service System (PSS) and the tools and methods used to provide such a solution. The internal structure of the company and its supply network are studied to understand the balance and VWS trade-off between technical risk decreasing, time to market reduction, innovation development and know-how protection. The role of synergies by VWS group companies is raised as a key to achieve the proper balance. These synergies are the result of the company strategy to focus on innovation rather than on know-how protection while the PSS structure and network provide great opportunities for time to market reduction and risk decreasing with optimized communication between stakeholders.

Friend lists allow Facebook users to group their friends and may be used to share certain information only with those in a specific list. This function has been around for several years, but has never gained any particular popularity among users, most of whom probably did not know it even existed a couple of years ago. In the fall of 2011, however, the function was updated and made more visible on the site. There are several possible uses of friend lists, such as privacy control, filtering of the news feed, self-presentation and targeted information sharing. This paper aims to investigate the extent to which friend lists are used by students today, as well as why students actually use their lists, i.e. for what purposes. Judging from the results of this study in comparison with earlier research, there seems to have been a somewhat recent increase in the awareness of the fact that friend lists actually do exist, but still most users tend not to utilize them. Moreover, the results indicate that friend lists quite rarely are used for privacy control, or anything else for that matter, probably due to a number of drawbacks that they possess as of today.