The recent advancement in computer-integrated manufacturing related technologies (e.g. internet of things, information technology and service-oriented architecture) has prompted the need for a novel effective, efficient and economical automatic identification and data collection solution for manufacturing scenario. Accurate and timely manufacturing front line information is essential to guarantee the functions and performance of enterprise information systems (EISs) deployed, and is the basis of entire information flow in enterprise. Both researchers and commercial players have made great contributions to the fields of enterprise information systems and data capturing technologies. However, real-time data processing and on-line knowledge support to seamlessly link up the EISs and shop floor front-line operations are still open to discuss. This research discusses an overall solution for manufacturing real-time field data capturing, processing and disseminating strategy in ubiquitous manufacturing environment, named Ubiquitous Manufacturing Platform (UMP). This research discusses the design and development of UMP, which is an innovative framework to integrate Auto-ID hardware devices and software services for facilitating manufacturing shop floor production management. The proposed event-driven UMP aims to enable shop floor real-time visibility and traceability, and bridge the gap between frontline operations and management level activities (e.g. planning and scheduling). On one hand, production management objectives are fulfilled through defined and configured services, and eventually carried out at shop floor operating sites with managed Auto-ID devices. On the other hand, the generated shop floor real-time field data is captured as events, which are then processed and aggregated to leveled meaningful information to satisfy various information requirements for different roles in an enterprise. UMP is expected to improve the efficiency and effectiveness of production supervision and decision making, and to reduce the production disturbances. This research has made the following achievements and contributions. Firstly, a scalable and reconfigurable infrastructure for manufacturing real-time field data capturing, processing and disseminating, named UMP, is developed based on several core technologies to achieve seamless dual-way connectivity and interoperability among enterprise application systems, shop floor, production line and workstation levels. Secondly, an innovative information processing mechanism, namely critical event model, is designed to connect the real-time field data in manufacturing processes to implied business context information. Based on this model, real-time field data is able to be organized in various abstract levels, so as to be useful for making adaptive enterprise decisions. Thirdly, a lightweight devices middleware solution named Gateway Operating System (GOS), is designed and proposed to support UMP. GOS enables a unified system interface for manufacturing companies to deploy and manage their heterogeneous Auto-ID devices. Furthermore, it allows multiple back-end manufacturing applications to share the same Auto-ID infrastructure, and shields the application systems from the implementation detail of enabling hardware devices. Fourthly, the gateway event processing procedure is presented to implement the engine for shop floor real-time field data capturing, processing and disseminating. Based on the Auto-ID infrastructure, it combines the concept of event and software agents into workflow management to realize real-time reconfigurable ubiquitous manufacturing. / published_or_final_version / Industrial and Manufacturing Systems Engineering / Doctoral / Doctor of Philosophy

With its mixing of real and virtual, Augmented Reality (AR) is a technology that has attracted lots of attention from the science community and is seen as a perfect way to visualize context-related information. Computer generated graphics is presented to the user overlaid and registered with the real world and hence augmenting it. Promising intelligence amplification and higher productivity, AR has been intensively researched over several decades but has yet to reach a broad audience. This thesis presents efforts in bringing Augmented Reality to mobile phones and thus to the general public. Implementing technologies on limited devices, such as mobile phones, poses a number of challenges that differ from traditional research directions. These include: limited computational resources with little or no possibility to upgrade or add hardware, limited input and output capabilities for interactive 3D graphics. The research presented in this thesis addresses these challenges and makes contributions in the following areas: Mobile Phone Computer Vision-Based Tracking The first contribution of thesis has been to migrate computer vision algorithms for tracking the mobile phone camera in a real world reference frame - a key enabling technology for AR. To tackle performance issues, low-level optimized code, using fixed-point algorithms, has been developed. Mobile Phone 3D Interaction Techniques Another contribution of this thesis has been to research interaction techniques for manipulating virtual content. This is in part realized by exploiting camera tracking for position-controlled interaction where motion of the device is used as input. Gesture input, made possible by a separate front camera, is another approach that is investigated. The obtained results are not unique to AR and could also be applicable to general mobile 3D graphics. Novel Single User AR Applications With short range communication technologies, mobile phones can exchange data not only with other phones but also with an intelligent environment. Data can be obtained for tracking or visualization; displays can be used to render graphics with the tracked mobile phone acting as an interaction device. Work is presented where a mobile phone harvests a sensor-network to use AR to visualize live data in context. Novel Collaboration AR Applications One of the most promising areas for mobile phone based AR is enhancing face-to-face computer supported cooperative work. This is because the AR display permits non-verbal cues to be used to a larger extent. In this thesis, face-to-face collaboration has been researched to examine whether AR increases awareness of collaboration partners even on small devices such as mobile phones. User feedback indicates that this is the case, confirming the hypothesis that mobile phones are increasingly able to deliver an AR experience to a large audience. / On the day of the defence date the status on articles III and VIII was: Accepted.

M. Tech. Business Information Systems / Focuses on tackling the lack of access to learning content and social resources in the higher learning environment of South Africa (SA). This research is important because South African institutions of higher learning are English language environments dominated by underprepared learners and overpopulated classrooms. Moreover, the country has lately seen increased numbers of learners entering higher learning institutions demonstrating a fair rate of acceptance of social media sites (SMS).

This thesis presents Illusion SDK: a general, extensible framework for augmented reality (AR) applications. Illusion provides loosely coupled or decoupled abstractions of sensors, trackers, and compositors. Implementations are optimized for particular use cases. Illusion’s architecture depends on only an event system and a 3D scene graph, so it is highly portable. Wrapping of third-party trackers is supported. Illusion’s current implementation targets Flash 11.4 and integrates with the Alternativa3D 8 graphics engine. To our knowledge, Illusion’s support for wrapping third-party trackers is unique among toolkits targeting the GPU-accelerated Web. Illusion performs well on MacBook Pro 13" mid-2010, where an intensive camera application can exceed 45 FPS. Generally, Illusion should perform well on hardware that uses shared video memory. Optimizations are needed for hardware that uses dedicated video memory. These optimizations are problematic in Flash 11.4 but should not generally be problematic in ports to other platforms.

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No description available.

To facilitate everyday activities, context-aware applications use sensors to detect what is happening and use increasingly complex mechanisms (e.g., by using big rule-sets or machine learning) to infer the user's context and intent. For example, a mobile application can recognize that the user is in a conversation and suppress any incoming calls. When the application works well, this implicit sensing and complex inference remain invisible. However, when it behaves inappropriately or unexpectedly, users may not understand its behavior. This can lead users to mistrust, misuse, or even abandon it. To counter this lack of understanding and loss of trust, context-aware applications should be intelligible, capable of explaining their behavior. We investigate providing intelligibility in context-aware applications and evaluate its usefulness to improve user understanding and trust in context-aware applications. Specifically, this thesis supports intelligibility in context-aware applications through the provision of explanations that answer different question types, such as: Why did it do X? Why did it not do Y? What if I did W, What will it do? How can I get the application to do Y? This thesis takes a three-pronged approach to investigating intelligibility by (i) eliciting the user requirements for intelligibility, to identify what explanation types end-users are interested in asking context-aware applications, (ii) supporting the development of intelligible context-aware applications with a software toolkit and the design of these applications with design and usability recommendations, and (iii) evaluating the impact of intelligibility on user understanding and trust under various situations and application reliability, and measuring how users use an interactive intelligible prototype. We show that users are willing to use well-designed intelligibility features, and this can improve user understanding and trust in the adaptive behavior of context-aware applications.

This thesis develops a generalized approach for decoupling how a context model is defined and executed from how context-aware data is acquired and managed within a given middleware system. Decoupling the model specification from the data will likely provide more avenues of context-aware investigations due to an increased flexibility in the choice of a middleware system for handling context data. We provide a detailed description of the approach developed for this decoupling task, called Inspect, Adapt, Model, and Integrate (IAMI). By engaging the steps we show that a context model need not be specifically tied to a given context-aware middleware. This successful decoupling will likely add to the future development of context-aware systems by allowing researchers to build upon existing frameworks as opposed to repeatedly engaging in ground-up development. Moreover, we submit that this decoupling is important in that the number of possible ways of representing and expressing a context model is potentially infinite, but the choice of context-aware middleware systems is limited.

Nominally, one can expect any user of modern technology to at least carry a handheld device of the class of an iPAQ (perhaps in the form of a cellphone). The availability of technology in the environment (home, office, public spaces) also continues to grow at an amazing pace. With advances in technology, it is feasible to remain connected and enjoy services that we care about, be it entertainment, sports, or plain work, anytime anywhere. We need a system that supports seamless migration of services from handhelds to the environment (or vice versa) and between environments. Virtualization technology is able to support such a migration by providing a common virtualized interface on both source and destination. In this dissertation, we focus on two levels of virtualization to address issues for seamless mobility. We first identify three different kinds of spaces and three axes to support mobility in these spaces. Then we present two systems that address these dimensions from different perspectives. For middleware level virtualization, we built a system called MobiGo that can capture the application states and restore the service execution with saved states at the destination platform. It provides the architectural elements for efficiently managing different states in the different spaces. Evaluation suggested that the overhead of the system is relatively small and meets user's expectation. On the other hand, for device level virtualization, Chameleon is a Xen-like system level virtualization system to support device level migration and automatic capability adaptation at a lower level. Chameleon is able to capture and restore device states and automatically accommodate the heterogeneity of devices to provide the migration of services. Device level virtualization can address some issues that cannot be addressed in middleware level virtualization. It also has less requirements than middleware level virtualization in order to be applied to existing systems. Through performance measurements, we demonstrate that Chameleon introduces minimal overhead while providing capability adaptation and device state migration for seamless mobility in ubiquitous computing environments.

We are rapidly entering a world with an immense amount of services and devices available to humans and machines. This is a promising future, however there are at least two major challenges for using these services and devices: (1) they have to be found and (2) after being found, they have to be selected amongst. A significant difficulty lies in not only finding most available services, but presenting the most useful ones. In most cases, there may be too many found services and devices to select from. Service discovery needs to become more aimed towards humans and less towards machines. The service discovery challenge is especially prevalent in ubiquitous computing. In particular, service and device flux, human overloading, and service relevance are crucial. This thesis addresses the quality of use of services and devices, by introducing a sophisticated discovery model through the use of new layers in service discovery. This model allows use of services and devices when current automated service discovery and selection would be impractical by providing service suggestions based on user activities, domain knowledge, and world knowledge. To explore what happens when such a system is in place, a wizard of oz study was conducted in a command and control setting. To address service discovery in ubiquitous computing new layers and a test platform were developed together with a method for developing and evaluating service discovery systems. The first layer, which we call the Enhanced Traditional Layer (ETL), was studied by developing the ODEN system and including the ETL within it. ODEN extends the traditional, technical service discovery layer by introducing ontology-based semantics and reasoning engines. The second layer, the Relevant Service Discovery Layer, was explored by incorporating it into the MAGUBI system. MAGUBI addresses the human aspects in the challenge of relevant service discovery by employing common-sense models of user activities, domain knowledge, and world knowledge in combination with rule engines.  The RESPONSORIA system provides a web-based evaluation platform with a desktop look and feel. This system explores service discovery in a service-oriented architecture setting. RESPONSORIA addresses a command and control scenario for rescue services where multiple actors and organizations work together at a municipal level. RESPONSORIA was the basis for the wizard of oz evaluation employing rescue services professionals. The result highlighted the importance of service naming and presentation to the user. Furthermore, there is disagreement among users regarding the optimal service recommendation, but the results indicated that good recommendations are valuable and the system can be seen as a partner. / Vi rör oss snabbt in i en värld med en enorm mängd tjänster och enheter som finns tillgängliga för människor och maskiner. Detta är en lovande framtid, men det finns åtminstone två stora utmaningar för att använda dessa tjänster och enheter: (1) de måste hittas och (2) rätt tjänst/enhet måste väljas. En betydande svårighet ligger i att, inte bara finna de mest lättillgängliga tjänsterna och enheterna, men också att presentera de mest användbara sådana. I de flesta fall kan det vara för många tjänster och enheter som hittas för att kunna välja mellan. Upptäckten av tjänster och enheter behöver bli mer anpassad till människor och mindre till maskiner. Denna utmaning är särskilt framträdande i desktopmetaforens efterföljare Ubiquitous Computing. (Det vill säga en form av interaktion med datorer som blivit integrerad i aktiviteter och objekt i omgivningen.) Framförallt tjänster och enheters uppdykande och försvinnande, mänsklig överbelastning och tjänstens relevans är avgörande utmaningar. Denna avhandling behandlar kvaliteten på användningen av tjänster och enheter, genom att införa en sofistikerad upptäcktsmodell med hjälp av nya lager i tjänsteupptäcktsprocessen. Denna modell tillåter användning av tjänster och enheter när nuvarande upptäcktsprocess och urval av dessa skulle vara opraktiskt, genom att ge förslag baserat på användarnas aktiviteter, domänkunskap och omvärldskunskap. För att utforska vad som händer när ett sådant system är på plats, gjordes ett så kallat Wizard of Oz experiment i ledningscentralen på en brandstation. (Ett Wizard Of Oz experiment är ett experiment där användaren tror att de interagerar med en dator, men i själva verket är det en människa som agerar dator.) För att hantera tjänste- och enhetsupptäckt i Ubiquitous Computing utvecklades nya lager och en testplattform tillsammans med en metod för att utveckla och utvärdera system för tjänste- och enhetsupptäckt. Det första lagret, som vi kallar Förbättrat Traditionellt Lager (FTL), studerades genom att utveckla ODEN och inkludera FTL i den. ODEN utökar det traditionella, datororienterade tjänste- och enhetsupptäcktslagret genom att införa en ontologibaserad semantik och en logisk regelmotor. Det andra skiktet, som vi kallar Relevant Tjänst Lager, undersöktes genom att införliva det i systemet MAGUBI. MAGUBI tar sig an de mänskliga aspekterna i den utmaning som vi benämner relevant tjänste- och enhetsupptäckt, genom att använda modeller av användarnas aktiviteter, domänkunskap och kunskap om världen i kombination med regelmotorer. RESPONSORIA är en webbaserad plattform med desktoputseende och desktopkänsla, och är ett system för utvärdering av ovanstående utmaning tillsammans med de tidigare systemen. Detta system utforskar tjänste- och enhetsupptäckt i ett tjänsteorienterat scenario. RESPONSORIA tar ett ledningsscenario för räddningstjänst där flera aktörer och organisationer arbetar tillsammans på en kommunal nivå. RESPONSORIA låg till grund för ett Wizard of Oz experiment där experimentdeltagarna var professionella räddningsledare. Resultatet underströk vikten av namngivning av tjänster och enheter samt hur dessa presenteras för användaren. Dessutom finns det oenighet bland användare om vad som är den optimala service-/enhets-rekommendationen, men resultaten visar att goda rekommendationer är värdefulla och systemet kan ses som en partner.