WebSocket vs WebRTC in the stream overlays of the Streamr Network

The Streamr Network is a decentralized publish-subscribe system. This thesis experimentally compares WebSocket and WebRTC as transport protocols in the system’s d-regular random graph type unstructured stream overlays. The thesis explores common designs for publish-subscribe and decentralized P2P systems. Underlying network protocols including NAT traversal are explored to understand how the WebSocket and WebRTC protocols function. The requirements set for the Streamr Network and how its design and implementations fulfill them are discussed. The design and implementations are validated with the use simulations, emulations and AWS deployed real-world experiments. The performance metrics measured from the real-world experiments are compared to related work. As the implementations using the two protocols are separate incompatible versions, the differences between them was taken into account during analysis of the experiments. Although the WebSocket versions overlay construction is known to be inefficient and vulnerable to churn, it is found to be unintentionally topology aware. This caused the WebSocket stream overlays to perform better in terms of latency. The WebRTC stream overlays were found to be more predictable and more optimized for small payloads as estimates for message propagation delays had a MEPA of 1.24% compared to WebSocket’s 3.98%. Moreover, the WebRTC version enables P2P connections between hosts behind NATs. As the WebRTC version’s overlay construction is more accurate, reliable, scalable, and churn tolerant, it can be used to create intentionally topology aware stream overlays to fully take over the results of the WebSocket implementation

Interfaces with the Ineffable

In recent years, Human Computer Interaction (HCI) designers and researchers have shifted focus from a primary concern with procedural, generic, and task based applications to applications that address messy, personal, and aesthetic experiences. These difficult to formalize experiences, such as feelings of intimacy, spirituality, or a sense of place, are conceptualized as experiences of the ineffable. In this work, I use a reflective design practice to look at two primary approaches to designing interfaces with the ineffable, one emphasizes reduction and the other openness to interpretation. I discuss issues of control and reification that result from the reduction approach and develop the interpretation approach as a viable alternative requiring a re-thinking design and evaluation strategies and criteria. These issues and approaches are explored in detail through the development of two case studies. Case study one addresses the ineffable experience of art and presents a series of applications for interfacing with the ineffable in the art museum. Case study two details the ineffable experience of affect and presents a system designed for augmenting affective presence in an office environment. To further this work, I examine new thinking in both HCI and Communication for understanding every day interpretive acts and the implications for design. In addition, I advance reflective design as a new process based practice for the field of Communication

Paradoxes of interactivity: perspectives for media theory, human-computer interaction, and artistic investigations

Current findings from anthropology, genetics, prehistory, cognitive and neuroscience indicate that human nature is grounded in a co-evolution of tool use, symbolic communication, social interaction and cultural transmission. Digital information technology has recently entered as a new tool in this co-evolution, and will probably have the strongest impact on shaping the human mind in the near future. A common effort from the humanities, the sciences, art and technology is necessary to understand this ongoing co- evolutionary process. Interactivity is a key for understanding the new relationships formed by humans with social robots as well as interactive environments and wearables underlying this process. Of special importance for understanding interactivity are human-computer and human-robot interaction, as well as media theory and New Media Art. "Paradoxes of Interactivity" brings together reflections on "interactivity" from different theoretical perspectives, the interplay of science and art, and recent technological developments for artistic applications, especially in the realm of sound

Paradoxes of Interactivity

Current findings from anthropology, genetics, prehistory, cognitive and neuroscience indicate that human nature is grounded in a co-evolution of tool use, symbolic communication, social interaction and cultural transmission. Digital information technology has recently entered as a new tool in this co-evolution, and will probably have the strongest impact on shaping the human mind in the near future. A common effort from the humanities, the sciences, art and technology is necessary to understand this ongoing co- evolutionary process. Interactivity is a key for understanding the new relationships formed by humans with social robots as well as interactive environments and wearables underlying this process. Of special importance for understanding interactivity are human-computer and human-robot interaction, as well as media theory and New Media Art. »Paradoxes of Interactivity« brings together reflections on »interactivity« from different theoretical perspectives, the interplay of science and art, and recent technological developments for artistic applications, especially in the realm of sound

The essential nature of on-the-job thinking: A phenomenological study of health and fitness professionals engaged in learning experiences.

For as long as learning is considered to include a cognitive element, then questions about how, and indeed, why, we think, remain crucial considerations for stakeholders in education, learning, and professional development. This study explores thinking in the specific context of on-the-job learning, or in other words, the essential nature of on-the-job thinking. Research generally portrays on-the-job learning, and the thinking assumed to take place therein, as an increasingly complex and poorly understood process. Beginning from a position rooted in health and fitness sector-specific research, and subsequently venturing into the wider landscape of fundamental theories in education and learning, a review of literature identifies the tendency for on-the-job learning to occur predominantly tacitly, as a main contributing factor to an evident impasse in our attempts to understand or study it further. The review subsequently traces this tacit-ness problem to its roots in cognitive science, or more specifically, in dual process theories which depict thinking as an action that is either conscious or unconscious (tacit). Despite a clear juxtaposition of doing and thinking, and the apportioning of comparative importance to the two, theories and models in education and learning seeking to expound the learning process, typically rely on definitions of thinking that are unclear or inconsistent, and fundamental concepts, typically originating from cognitive science, that are obscure and/or paradoxical. It is argued, therefore, that in order to further our understanding of on-the-job learning, a clearer and more robust definition of thinking is warranted, as an alternative theoretical foundation for modern education and learning theories, based not solely on explanations derived from cognitive science, but also on descriptions derived from more philosophical endeavours, namely, phenomenology. Following a deep and reflective phenomenological analysis of personal fitness trainers' accounts of their onthe- job thinking, using modern as well as classical phenomenological methods, the study aims to, first, uncover a re-conceptualised and less problematic description of on-the-job thinking, and second, to evaluate the actual implications of such a reconceptualisation. The description that results, which is also presented in the text as an analogy, casts light on the centrality of feelings, as well as concepts either general or pertaining to self, as key influential factors guiding on-the-job learning outcomes, portrays on-the-job thinking as an integrated activity that is not isolated or separated from interaction with self, other, or the world, and finally, challenges traditional conceptualisations of thinking in light of the challenging notions of conscious awareness and volition. In so doing, the results of this study provide an alternative view of thinking in the context of on-the-job learning by personal fitness trainers, or indeed other professionals, from a conceptual/theoretical standpoint, while also revealing specific features of the phenomenon with immediate and more practical applications as prospective constituents of existing initiatives or interventions designed to facilitate and enhance on-the-job learning in the health and fitness sector, and perhaps further afield

5TH applied research conference in Africa

Abstract: Please refer to full text to view abstrac