This thesis presents an ethnographic study that aims at explicating the work of creating content in Minecraft. The existing literature paves the way in understanding Minecraft’s community by providing fragments of what players do. However, the game is studied mainly from a ludic perspective or is treated as a resource to explore distinct research agendas, instead of a field of study in itself. As such, particular phenomena that are situated inside Minecraft’s community are lost. The conducted fieldwork discovered the invisible digital economy that is part of this community. More specifically, the chapters to follow elaborate on the actors involved in this economy, covering their roles, responsibilities and goals. Furthermore, the lived work of content production is unpacked by presenting the various work practices members attend to in commissioning, creating, and delivering Minecraft content. It also becomes evident that there is a complex division of labour at play, which is based on a fragmented infrastructure as Minecraft itself does not support the wide range of activities that are necessary for carrying out the work. Essentially, actors bootstrap the market’s infrastructure by appropriating or even creating bespoke systems for conducting the various work practices that are entailed in this business. On top of that, these systems are utilised for articulation work, which is necessary for tracking progress between the geographically dispersed actors, accounting for conducted work and addressing contingent scenarios. The main contribution of this PhD project is the discovery of this digital economy, which evidently plays a significant role in Minecraft’s current form and development. Additionally, prevailing understandings of Minecraft’s ecosystem are re-visited, re-examined, and re-specified, based on the empirical evidence presented in this thesis. Finally, a number of design implications are raised with regard to addressing the game’s lack of CSCW support.

The work presented in this thesis focuses on solving course timetabling problems, a variant of education timetabling. Automated timetabling is a popular topic among researchers and practitioners because manual timetable construction is impractical, if not impossible, as it is known to be NP-hard. A two-stage approach is investigated. The first stage involves finding feasible solutions. Monte Carlo Tree Search (MCTS) is utilized in this stage. As far as we are aware, it is used for the first time in addressing the timetabling problem. It is a relatively new search method and has achieved breakthrough in the domain of games particularly Go. Several enhancements are attempted on MCTS such as heuristic based simulations and pruning. We also compare the effectiveness of MCTS with Graph Coloring Heuristic (GCH) and Tabu Search (TS) based methods. Initial findings show that a TS based method is more promising, so we focus on improving TS. We propose an algorithm called Tabu Search with Sampling and Perturbation (TSSP). Among the enhancements that we introduced are event sampling, a novel cost function and perturbation. Furthermore, we hybridize TSSP with Iterated Local Search (ILS). The second stage focuses on improving the quality of feasible solutions. We propose a variant of Simulated Annealing called Simulated Annealing with Reheating (SAR). SAR has three features: a novel neighborhood examination scheme, a new way of estimating local optima and a reheating scheme. The rigorous setting of initial and end temperature in conventional SA is bypassed in SAR. Precisely, reheating and cooling were applied at the right time and level, thus saving time allowing the search to be performed efficiently. One drawback of SAR is having to preset the composition of neighborhood structures for the datasets. We present an enhanced variant of the SAR algorithm called Simulated Annealing with Improved Reheating and Learning (SAIRL). We propose a reinforcement learning based method to obtain a suitable neighborhood structure composition for the search to operate effectively. We also propose to incorporate the average cost changes into the reheated temperature function. SAIRL eliminates the need for tuning parameters in conventional SA as well as neighborhood structures composition in SAR. Experiments were tested on four publicly available datasets namely Socha, International Timetabling Competition 2002 (ITC02), International Timetabling Competition 2007 (ITC07) and Hard. Our results are better or competitive when compared with other state of the art methods where new best results are obtained for many instances.

Protein classification databases are widely used in the prediction of protein structure and function, and amongst these databases the manually-curated Structural Classification of Proteins database (SCOP) is considered to be a gold standard. In SCOP, functional relationships are described by hyperfamily and superfamily categories and structural relationships are described by family, species and protein categories. We present a method to calculate a difference measure between pairs of proteins that can be used to reproduce SCOP2 structural relationship classifications, and that can also be used to reproduce a subset of functional relationship classifications at the superfamily level. Calculating the difference measure requires first finding the best correspondence between atoms in two protein configurations. The problem of finding the best correspondence is known as the unlabelled, partial matching problem. We consider the unlabelled, partial matching problem through a detailed analysis of the approach presented in Green and Mardia (2006). Using this analysis, and applying domain-specific constraints, we develop a new algorithm called GProtA for protein structure alignment. The proposed difference measure is constructed from the root mean squared deviation of the aligned protein structures and a binary similarity measure, where the binary similarity measure takes into account the proportions of atoms matching from each configuration. The GProtA algorithm and difference measure are applied to protein structure data taken from the Protein Data Bank. The difference measure is shown to correctly classify 62 of a set of 72 proteins into the correct SCOP family categories when clustered. Of the remaining 9 proteins, 2 are assigned incorrectly and 7 are considered indeterminate. In addition, a method for deriving characteristic signatures for categories is proposed. The signatures offer a mechanism by which a single comparison can be made to judge similarity to a particular category. Comparison using characteristic signatures is shown to correctly delineate proteins at the family level, including the identification of both families for a subset of proteins described by two family level categories.

Domestic Networks are gaining in complexity, with an increasing number and variety of devices. Increasing complexity results in greater difficulty managing configuration and troubleshooting when problems occur. This thesis presents strategies to assist users in managing the complexity of their networks. The work is split into several parts. First, configuration changes are tracked and users are presented with a timeline of changes to their network. Provision of a selective undo system is the second feature. The undo facility is designed to allow any change to be undone independently of any other. Users are also given the option of reverting to an earlier point, either before a specific change, or to a specific timestamp. The next feature is use of notifications. Any changes that require further actions can be broadcast to users directly. Changing Wi-Fi configuration is one example. The range of devices in use makes changing Wi-Fi configuration (and the subsequent reconfiguration of devices) a challenge, because the devices affected may be part of the infrastructure of a home (lights or thermostat for example). Because these devices have unique methods of network setup, restoring connectivity to every device can be challenging. This thesis also presents a method of changing Wi-Fi configuration which allows users a grace period to reconnect all their devices. Each of these features was assessed by a user study, the results of which are also discussed.

abstract: Dieterich Buxtehude (ca. 1637-1707) is known for his many organ works. However, no significant portion of his choral music is in the standard performing repertoire. Buxtehude's large-scale choral work Membra Jesu Nostri should be considered a seminal "passion" composition in part because of its historic position in early German Lutheran church music. It also serves as an example of the heightened levels of affect in a seventeenth century devotional passion. To better understand Buxtehude and his music, an overview of his life, career and religious beliefs are discussed, including the incorporation of pietism and mysticism in his cantata, Membra Jesu Nostri. Details of the composition's structure, unifying thematic elements and text sources with translations are included. Historical performance practices are discussed, including the composer's probable intent of having one of the seven cantatas performed every day before Easter. This research study also provides conductors with a variety of practical performance considerations. Through these observations, it will be shown that Buxtehude's Membra Jesu Nostri is one of the most well-conceived and well-constructed choral works of the early Baroque era. / Dissertation/Thesis / D.M.A. Music 2012

Type theory (with dependent types) was introduced by Per Martin-Löf with the intention of providing a foundation for constructive mathematics. A part of constructive mathematics is type theory itself, hence we should be able to say what type theory is using the formal language of type theory. In addition, metatheoretic properties of type theory such as normalisation should be provable in type theory. The usual way of defining type theory formally is by starting with an inductive definition of precontexts, pretypes and preterms and as a second step defining a ternary typing relation over these three components. Well-typed terms are those preterms for which there exists a precontext and pretype such that the relation holds. However, if we use the rich metalanguage of type theory to talk about type theory, we can define well-typed terms directly as an inductive family indexed over contexts and types. We believe that this latter approach is closer to the spirit of type theory where objects come intrinsically with their types. Internalising a type theory with dependent types is challenging because of the mutual definitions of types, terms, substitution of terms and the conversion relation. We use induction induction to express this mutual dependency. Furthermore, to reduce the type-theoretic boilerplate needed for reasoning in the syntax, we encode the conversion relation as the equality type of the syntax. We use equality constructors thus we define the syntax as a quotient inductive type (a special case of higher inductive types from homotopy type theory). We define the syntax of a basic type theory with dependent function space, a base type and a family over the base type as a quotient inductive inductive type. The definition of the syntax comes with a notion of model and an eliminator: whenever one is able to define a model, the eliminator provides a function from the syntax to the model. We show that this method of representing type theory is practically feasible by defining a number of models: the standard model, the logical predicate interpretation for parametricity (as a syntactic translation) and the proof-relevant presheaf logical predicate interpretation. By extending the latter with a quote function back into the syntax, we prove normalisation for type theory. This can be seen as a proof of normalisation by evaluation. Internalising the syntax of type theory is not only of theoretical interest. It opens the possibility of type-theoretic metaprogramming in a type-safe way. This could be used for generic programming in type theory and to implement extensions of type theory which are justified by models such as guarded type theory or homotopy type theory.

Drugs that are preferentially absorbed through the stomach or the small intestine have a narrow time window for absorption since passage through this region of the gastrointestinal tract is rapid. A drug delivery system that can adhere to the gastric epithelium will substantially slow down drug transit and help overcome this problem. To achieve this, this study proposes the novel use of a glycan-binding adhesion protein from Helicobacter pylori, BabA, to create targeted drug delivery vectors that can mimic the attachment of this bacterium to the gastric epithelium. In this work, a recombinant form of BabA was expressed in the periplasmic space of Escherichia coli; it was found that after the incorporation of a C-terminal hexa-lysine tag, the expression and purification of this protein was significantly improved to amounts that enabled its subsequent characterisation and application. Recombinant BabA retained the highly selective glycan-binding properties of H. pylori and next, its crystal structure was solved in the absence and presence of Lewisb – a glycan well studied for its role in serving as a receptor for BabA. The structural models revealed that Lewisb binding occurred through a network of hydrogen bonds within a single, shallow binding pocket at the tip of a β-unit in BabA. Binding studies then confirmed that this site was also responsible for the recognition of other glycan receptors. Using this insight, recombinant BabA was conjugated to model drug delivery vectors via a linkage that favoured exposure of its glycan-binding β-unit; the binding properties of BabA successfully translated to these model BabA-vectors. The research presented in this thesis lays a strong foundation for future work to assess the in vitro and in vivo efficacy of biomimetic BabA drug carriers.

Les forêts françaises et luxembourgeoises sont des espaces économiques, destinés à la production de ressources ligneuses. Les forêts publiques relevant du régime forestier et les forêts privées ne sont pas soumises au même cadre législatif, expliquant les différences de mise en œuvre intellectuelle de la propriété forestière, au cours des phases de planification et de gestion, et de mise en œuvre matérielle de la propriété forestière, au cours des travaux et de l’exploitation. De plus, la multifonctionnalité de la forêt lui confère une grande importance environnementale au sens large. En effet, les espaces forestiers, gérés durablement, sont protecteurs des facteurs biotiques et abiotiques. Même si le droit forestier était particulièrement destiné à protéger la capacité de production de ressource ligneuse, il se révèle, à présent, être un outil de prévention et de répression permettant de soutenir l’accomplissement des missions économiques, écologiques et sociales attribuées à la forêt. En outre, le rapport complexe entre forêt et société impose une évolution constante de la valorisation et de l’organisation de l’accès du public aux espaces forestiers. Partageant une histoire commune, la France et le Grand-Duché de Luxembourg ont adopté une approche théorique de la législation forestière analogue, rehaussée de différences sectorielles révélatrices des enjeux et des préoccupations auxquels doit faire face le gestionnaire forestier pour garantir la pérennité de la forêt, des espèces qui la composent, des habitats qu’elle représente et du cadre de vie qu’elle offre / French and Luxembourg forests are economic areas for the production of wood products. Public forests and private forests are not subject to the same legislative framework. This explains the differences in forest management policy according to forest ownership in the planning and management phases, and in the implementation of forestry and harvesting operations. Also, forest multifunctionality is of great environmental importance in the broadest sense. Sustainably managed forested areas protect biotic and abiotic factors. Although forestry law was specifically intended to protect wood products production capacity, it appears at present to be a preventive and repressive tool to support the achievement of forest-related economic, ecological and social missions. In addition, the complex relationship between forests and society demands constant reevaluation of the importance and organization of public access to forest areas. Sharing a common history, France and the Grand Duchy of Luxembourg have adopted analogous theoretical approaches to forest legislation. This is brought into focus by the revealing nature of sectoral differences as to the stakes at issue and concerns faced by forest managers to ensure the sustainability of the forest, of its component species, of its habitats and the living environment it offers

Mixed reality games combine interactive digital content with real world environments, objects, and actors by utilizing a multitude of different sensors. While offering plenty of opportunities for designers, they are also notoriously difficult to design. This is in part due to them still being a relatively new form of gaming with only very few examples of commercially successful games. This means that the majority of aspiring designers lacks knowledge about the design space of these games – something that is crucial in order to create new and exciting experiences. While there exist several authoring tools to facilitate the development of mixed reality games, these tools do not provide guidance on the game design aspects. The design of mixed reality games is likewise bringing together experts from different domains (e.g. game design, technology, locales). In order to support this multifaceted and collaborative design process I have developed the Mixed Reality Game Cards. These are a deck of ideation cards that encapsulate the design space of mixed reality games in the form of physical playing cards. The cards can be used for rapid idea generation (i.e. creating a multitude of ideas from scratch in a short time) and in-depth idea development (i.e. further expanding and refining an idea). The Mixed Reality Game Cards consist of four types of cards to support idea generation as well as idea development. Opportunity Cards are the building blocks of an idea and describe potential elements of a design. Question Cards prompt the design group to consider the experience from different angles to refine the design. Challenge Cards surface typical design issues and problems that might occur. These domain-specific cards are supported by Theme Cards that are taken from the board game Dixit in order to provide additional domain-extrinsic sources of inspiration. I developed the Mixed Reality Game Cards iteratively over the course of seven studies following a Research through Design approach. This provided valuable insight into what makes ideation cards such powerful facilitators of collaborative design sessions. I identify content, appearance, and rules as crucial elements under direct control of an ideation card designer and tangible as well as playful interactions as dynamics that emerge during an ideation session. This thesis describes the development of the Mixed Reality Game Cards and uses the insights gained from this process to reflect on ideation cards as design tools in general, expanding our understanding of them.

Portfolio optimisation problems are generally concerned with allocating funds to investments. The goal is to find an allocation that minimises risk subject to some certain constraints. To attain robust solutions from the optimisation, it is vital to ensure that the model is able to properly represent the underlying uncertainty in portfolio management. The main source of uncertainty in managing portfolios is from asset returns fluctuation. Typically, it is depicted through scenarios or return distributions which are commonly assumed to be normal. Such assumption, however, does not illustrate the true characteristics of financial asset returns and thus distorts the representation of returns, risks and interrelationship of assets in a portfolio. This thesis presents novel approaches to represent the uncertainty in international portfolio management in order to mitigate risks associated. Three main issues are covered in our studies. The first issue deals with an approach to hedge risk from exchange rates of a multi-currency portfolio. A hedging mechanism is incorporated into a portfolio optimisation model to produce a portfolio that is optimal in terms of asset and currency exposure. Costs associated to exchange rate hedging are also included into the model to improve accuracy in calculating risk and return of the portfolio. The second issue is about representing the uncertainty of multiple assets in a portfolio through scenarios. Under the assumption of normality, some risk and return characteristics of assets are omitted from standard scenario generation method. We present a novel approach to extract more accurate information from assets to generate realistic scenarios. A two-stage stochastic international portfolio optimisation model is formulated accordingly to create portfolios that are expected to be more efficient than portfolios optimised with scenarios generated from the standard approach. The last issue is associated with an approach to keep portfolio's efficiency over its investment horizon through continual reallocation, known as portfolio rebalancing. Since the uncertainty regarding changes in financial market conditions diminishes the efficiency of conventional rebalancing strategies, we propose a new rebalancing method and formulate it as a stochastic optimisation problem. The proposed rebalancing strategy aims to reallocate the portfolio to attain a high probability of positive returns and low probability of negative returns under second-order stochastic dominance criteria. A portfolio implementing the new rebalancing strategy is expected to outperform a portfolio that follows traditional rebalancing methods in terms of portfolio returns. Overall, the thesis aims to create a richer portfolio optimisation model as well as to extract the correct information from financial markets to better cope with the underlying uncertainty in portfolio management.