Information access tasks and evaluation for personal lifelogs

Emerging personal lifelog (PL) collections contain permanent digital records of information associated with individuals’ daily lives. This can include materials such as emails received and sent, web content and other documents with which they have interacted, photographs, videos and music experienced passively or created, logs of phone calls and text messages, and also personal and contextual data such as location (e.g. via GPS sensors), persons and objects present (e.g. via Bluetooth) and physiological state (e.g. via biometric sensors). PLs can be collected by individuals over very extended periods, potentially running to many years. Such archives have many potential applications including helping individuals recover partial forgotten information, sharing experiences with friends or family, telling the story of one’s life, clinical applications for the memory impaired, and fundamental psychological investigations of memory. The Centre for Digital Video Processing (CDVP) at Dublin City University is currently engaged in the collection and exploration of applications of large PLs. We are collecting rich archives of daily life including textual and visual materials, and contextual context data. An important part of this work is to consider how the effectiveness of our ideas can be measured in terms of metrics and experimental design. While these studies have considerable similarity with traditional evaluation activities in areas such as information retrieval and summarization, the characteristics of PLs mean that new challenges and questions emerge. We are currently exploring the issues through a series of pilot studies and questionnaires. Our initial results indicate that there are many research questions to be explored and that the relationships between personal memory, context and content for these tasks is complex and fascinating

Evaluating Audience Engagement of an Immersive Performance on a Virtual Stage

Presenting theatrical performances in virtual reality (VR) has been an active area of research since the early 2000\u27s. VR provides a unique form of storytelling, which is made possible through the use of physically and digitally distributed 3D worlds. We describe a methodology for determining audience engagement in a virtual theatre performance. We use a combination of galvanic skin response (GSR) data, self-reported positive and negative affect schedule (PANAS), post-viewing reflection, and a think aloud method to assess user reaction to the virtual reality experience. In this study, we combine the implicit physiological data from GSR with explicit user feedback to produce a holistic metric for assessing immersion. Although the study evaluated a particular artistic work, the methodology of the study provides a foundation for conducting similar research. The combination of PANAS, self reflection, and the think aloud in conjunction with GSR data constitutes a novel approach in the study of live performance in virtual reality. The approach is also extendable to include other implicit measures such as pulse rate, blood pressure, or eye tracking. Our case study compares the experience of viewing the performance on a computer monitor to viewing with a head mounted display. Results showed statistically significant differences based on viewing platform in the PANAS self-report metric, as well as GSR measurements. Feedback obtained via the think aloud and reflection analysis also emphasized qualitative differences between the two viewing scenarios

Capturing route experiences

Tese de mestrado, Informática, Universidade de Lisboa, Faculdade de Ciências, 2014Several systems currently exist to support creation of location-based stories and capturing of life experiences. However, it has been shown that there is a trade-off between fully committing to the authoring process and “staying in the moment”, which produces strain and increases authoring effort. The present work addresses this problem by leveraging the large amount of third party content, readily available through various web services. More concretely, we re-imagine in-situ storytelling process, providing authors with suggestions of external story elements, such as Foursquare1 venues, which they can embed directly into the story. We explore whether with this approach authors are able to balance between producing novel and reusing existing content, saving time and effort whenever necessary. Results from our two user studies suggest that suggestions can potentially reduce the authoring effort, but only provided they are relevant enough. At the same time, they can significantly improve the viewing experience, provided they are content-rich: Foursquare venues, encompassing photos, reviews and comments, are a good example. We also found that authors valued stories’ individuality more than viewers, as the former were somewhat reluctant to “dilute” their personal content with external data, whereas the latter appreciated the social aspects contributed by suggestions

Digital life stories: Semi-automatic (auto)biographies within lifelog collections

Our life stories enable us to reflect upon and share our personal histories. Through emerging digital technologies the possibility of collecting life experiences digitally is increasingly feasible; consequently so is the potential to create a digital counterpart to our personal narratives. In this work, lifelogging tools are used to collect digital artifacts continuously and passively throughout our day. These include images, documents, emails and webpages accessed; texts messages and mobile activity. This range of data when brought together is known as a lifelog. Given the complexity, volume and multimodal nature of such collections, it is clear that there are significant challenges to be addressed in order to achieve coherent and meaningful digital narratives of our events from our life histories. This work investigates the construction of personal digital narratives from lifelog collections. It examines the underlying questions, issues and challenges relating to construction of personal digital narratives from lifelogs. Fundamentally, it addresses how to organize and transform data sampled from an individual’s day-to-day activities into a coherent narrative account. This enquiry is enabled by three 20-month long-term lifelogs collected by participants and produces a narrative system which enables the semi-automatic construction of digital stories from lifelog content. Inspired by probative studies conducted into current practices of curation, from which a set of fundamental requirements are established, this solution employs a 2-dimensional spatial framework for storytelling. It delivers integrated support for the structuring of lifelog content and its distillation into storyform through information retrieval approaches. We describe and contribute flexible algorithmic approaches to achieve both. Finally, this research inquiry yields qualitative and quantitative insights into such digital narratives and their generation, composition and construction. The opportunities for such personal narrative accounts to enable recollection, reminiscence and reflection with the collection owners are established and its benefit in sharing past personal experience experiences is outlined. Finally, in a novel investigation with motivated third parties we demonstrate the opportunities such narrative accounts may have beyond the scope of the collection owner in: personal, societal and cultural explorations, artistic endeavours and as a generational heirloom

Semantic interpretation of events in lifelogging

The topic of this thesis is lifelogging, the automatic, passive recording of a person’s daily activities and in particular, on performing a semantic analysis and enrichment of lifelogged data. Our work centers on visual lifelogged data, such as taken from wearable cameras. Such wearable cameras generate an archive of a person’s day taken from a first-person viewpoint but one of the problems with this is the sheer volume of information that can be generated. In order to make this potentially very large volume of information more manageable, our analysis of this data is based on segmenting each day’s lifelog data into discrete and non-overlapping events corresponding to activities in the wearer’s day. To manage lifelog data at an event level, we define a set of concepts using an ontology which is appropriate to the wearer, applying automatic detection of concepts to these events and then semantically enriching each of the detected lifelog events making them an index into the events. Once this enrichment is complete we can use the lifelog to support semantic search for everyday media management, as a memory aid, or as part of medical analysis on the activities of daily living (ADL), and so on. In the thesis, we address the problem of how to select the concepts to be used for indexing events and we propose a semantic, density- based algorithm to cope with concept selection issues for lifelogging. We then apply activity detection to classify everyday activities by employing the selected concepts as high-level semantic features. Finally, the activity is modeled by multi-context representations and enriched by Semantic Web technologies. The thesis includes an experimental evaluation using real data from users and shows the performance of our algorithms in capturing the semantics of everyday concepts and their efficacy in activity recognition and semantic enrichment

Messhu-gata musen nettowaku ni okeru supekutoramu kenchi to MAC-so purotokoru ni kansuru kenkyu

制度:新 ; 報告番号:甲3458号 ; 学位の種類:博士(国際情報通信学) ; 授与年月日:2011/11/16 ; 早大学位記番号:新578

Edição e visualização criativa de vídeo

Tese de mestrado, Engenharia Informática (Arquitectura, Sistemas e Redes de Computadores), Universidade de Lisboa, Faculdade de Ciências, 2009Este trabalho pretende contribuir para as áreas da visualização e edição criativa de vídeo, criando novas formas de visualização de vídeos. Os vídeos são constituídos por imagens, texto e áudio que variam ao longo do tempo, constituindo informação muito rica mas que ao mesmo tempo é muito complexa. Esta complexidade oferece um desafio a explorar, e a visualização surge como uma forma de exploração e ajuda para simplificar o acesso à informação contida nos vídeos. Com essa informação podem ser criados espaços de vídeo que podem ser usados como plataforma de suporte à expressão da criatividade e como suporte a tarefas de edição, através de funcionalidades como pesquisa e organização de vídeos. Nesse sentido foi desenvolvido um ambiente interactivo para visualizar e explorar espaços de vídeo com ênfase em aspectos da cor e movimento dos vídeos, por serem propriedades visuais importantes, tanto a um nível individual como colectivo – o ColorsInMotion. Este sistema é constituído por dois módulos: o Video Analyzer e o Viewer. No Video Analyzer são postas em prática técnicas de processamento e análise de vídeo e são criadas visualizações em diferentes espaços de cor, permitindo ver diferentes perspectivas sobre os resultados. No Viewer dá-se ênfase à visualização interactiva, permitindo ao utilizador navegar num espaço de vídeos e explorá-lo, tanto a nível colectivo como individual, de forma criativa. No Viewer é possível efectuar pesquisas por cor, servindo também como um sistema de organização, permitindo explorar ligações entre os diferentes vídeos, neste caso, num contexto cultural, com vídeos de dança e música de vários países. Também foram exploradas várias formas de interacção com o sistema, como a interacção por detecção de cor e a interacção gestual, que são indicadas para ambientes de instalação interactiva.This work intends to make a contribution in the field of creative video editing and visualization, developing new ways to visualize videos. Videos are made of images, text and audio all combined and changing with time, making for information, that is, at the same time, very rich and very complex. This complexity offers a challenge to explore, and visualization is one way to help explore and simplify the access to this information, that is contained within the videos. With this information we can create video spaces that can be used as a platform to support the expression of creativity and as a help to video editing tasks, through features such as video search and organization. With this purpose in mind, an interactive environment was developed to visualize and explore video spaces with focus on important visual video properties like color and movement – ColorsInMotion. This system has two modules: the Video Analyzer and the Viewer. In the Video Analyzer we use the techniques of video processing and analysis, and we create different visualizations on different color spaces, allowing different perspectives over the results. In the Viewer we focus on interactive visualization and creativity, giving the user the possibility to browse and explore video spaces, in a creative way, on a collective level, but also on an individual level. In the Viewer we can search by color, serving as a system to organize videos and also serving as a platform to explore connections between different vídeos, in this case, in a cultural context, with videos of dances and music from various countries. We also explored interaction methods to use with the system, like the color detection interaction and the gesture based interaction, that are good for artistic installation environments

Channel assignment and routing in cooperative and competitive wireless mesh networks

This thesis was submitted for the degree of Docter of Philosophy and awarded by Brunel University.In this thesis, the channel assignment and routing problems have been investigated for both cooperative and competitive Wireless Mesh networks (WMNs). A dynamic and distributed channel assignment scheme has been proposed which generates the network topologies ensuring less interference and better connectivity. The proposed channel assignment scheme is capable of detecting the node failures and mobility in an efficient manner. The channel monitoring module precisely records the quality of bi-directional links in terms of link delays. In addition, a Quality of Service based Multi-Radio Ad-hoc On Demand Distance Vector (QMR-AODV) routing protocol has been devised. QMR-AODV is multi-radio compatible and provides delay guarantees on end-to-end paths. The inherited problem of AODV’s network wide flooding has been solved by selectively forwarding the routing queries on specified interfaces. The QoS based delay routing metric, combined with the selective route request forwarding, reduces the routing overhead from 24% up to 36% and produces 40.4% to 55.89% less network delays for traffic profiles of 10 to 60 flows, respectively. A distributed channel assignment scheme has been proposed for competitive WMNs, where the problem has been investigated by applying the concepts from non-cooperative bargaining Game Theory in two stages. In the first stage of the game, individual nodes of the non-cooperative setup is considered as the unit of analysis, where sufficient and necessary conditions for the existence of Nash Equilibrium (NE) and Negotiation-Proof Nash Equilibrium (N-PNE) have been derived. A distributed algorithm has been presented with perfect information available to the nodes of the network. In the presence of perfect information, each node has the knowledge of interference experience by the channels in its collision domain. The game converges to N-PNE in finite time and the average fairness achieved by all the nodes is greater than 0.79 (79%) as measured through Jain Fairness Index. Since N-PNE and NE are not always a system optimal solutions when considered from the end-nodes prospective, the model is further extended to incorporate non-cooperative end-users bargaining between two end user’s Mesh Access Points (MAPs), where an increase of 10% to 27% in end-to-end throughput is achieved. Furthermore, a non-cooperative game theoretical model is proposed for end-users flow routing in a multi-radio multi-channel WMNs. The end user nodes are selfish and compete for the channel resources across the WMNs backbone, aiming to maximize their own benefit without taking care for the overall system optimization. The end-to-end throughputs achieved by the flows of an end node and interference experienced across the WMNs backbone are considered as the performance parameters in the utility function. Theoretical foundation has been drawn based on the concepts from the Game Theory and necessary conditions for the existence of NE have been extensively derived. A distributed algorithm running on each end node with imperfect information has been implemented to assess the usefulness of the proposed mechanism. The analytical results have proven that a pure strategy Nash Equilibrium exists with the proposed necessary conditions in a game of imperfect information. Based on a distributed algorithm, the game converges to a stable state in finite time. The proposed game theoretical model provides a more reasonable solution with a standard deviation of 2.19Mbps as compared to 3.74Mbps of the random flow routing. Finally, the Price of Anarchy (PoA) of the system is close to one which shows the efficiency of the proposed scheme.The Higher Education Commission of Pakistan and the University of Engineering and Technology, Peshawar

Security Policies That Make Sense for Complex Systems: Comprehensible Formalism for the System Consumer

Information Systems today rarely are contained within a single user workstation, server, or networked environment. Data can be transparently accessed from any location, and maintained across various network infrastructures. Cloud computing paradigms commoditize the hardware and software environments and allow an enterprise to lease computing resources by the hour, minute, or number of instances required to complete a processing task. An access control policy mediates access requests between authorized users of an information system and the system\u27s resources. Access control policies are defined at any given level of abstraction, such as the file, directory, system, or network, and can be instantiated in layers of increasing (or decreasing) abstraction. For the system end-user, the functional allocation of security policy to discrete system components, or subsystems, may be too complex for comprehension. In this dissertation, the concept of a metapolicy, or policy that governs execution of subordinate security policies, is introduced. From the user\u27s perspective, the metapolicy provides the rules for system governance that are functionally applied across the system\u27s components for policy enforcement. The metapolicy provides a method to communicate updated higher-level policy information to all components of a system; it minimizes the overhead associated with access control decisions by making access decisions at the highest level possible in the policy hierarchy. Formal definitions of policy often involve mathematical proof, formal logic, or set theoretic notation. Such policy definitions may be beyond the capability of a system user who simply wants to control information sharing. For thousands of years, mankind has used narrative and storytelling as a way to convey knowledge. This dissertation discusses how the concepts of storytelling can be embodied in computational narrative and used as a top-level requirements specification. The definition of metapolicy is further discussed, as is the relationship between the metapolicy and various access control mechanisms. The use of storytelling to derive the metapolicy and its applicability to formal requirements definition is discussed. The author\u27s hypothesis on the use of narrative to explain security policy to the system user is validated through the use of a series of survey instruments. The survey instrument applies either a traditional requirements specification language or a brief narrative to describe a security policy and asks the subject to interpret the statements. The results of this research are promising and reflect a synthesis of the disciplines of neuroscience, security, and formal methods to present a potentially more comprehensible knowledge representation of security policy