Cloud computing and context-awareness: A study of the adapted user experience

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Today, mobile technology is part of everyday life and activities and the mobile ecosystems are blossoming, with smartphones and tablets being the major growth drivers. The mobile phones are no longer just another device, we rely on their capabilities in work and in private. We look to our mobile phones for timely and updated information and we rely on this being provided any time of any day at any place. Nevertheless, no matter how much you trust and love your mobile phone the quality of the information and the user experience is directly associated with the sources and presentation of information. In this perspective, our activities, interactions and preferences help shape the quality of service, content and products we use. Context-aware systems use such information about end-users as input mechanisms for producing applications based on mobile, location, social, cloud and customized content services. This represents new possibilities for extracting aggregated user-centric information and includes novel sources for context-aware applications. Accordingly, a Design Research based approach has been taken to further investigate the creation, presentation and tailoring of user-centric information. Through user evaluated experiments findings show how multi-dimensional context-aware information can be used to create adaptive solutions tailoring the user experience to the users’ needs. Research findings in this work; highlight possible architectures for integration of cloud computing services in a heterogeneous mobile environment in future context-aware solutions. When it comes to combining context-aware results from local computations with those of cloud based services, the results provide findings that give users tailored and adapted experiences based on the collective efforts of the two

The Live Programming Lecturing Technique: A Study of the Student Experience in Introductory and Advanced Programming Courses

This paper investigates the topic of teaching programming in higher education. The teaching method often referred to as live programming has become a widely applied lecturing strategy for teaching programming subjects in an interactive fashion. Lectures based on live programming normally involve live demonstrations, explanations and interaction with the students. Although this technique seems to be very popular amongst students and instructors, we hypothesise that it also involves potential challenges. In this paper, we investigate the perceived difficulty and promise of following such an approach from a student perspective. We present results from interviews with 1st and 2nd year IT Bachelor students about their experience with live programming. Our results indicate that students’ engagement and desire to learn through active learning techniques still are very much valid also in introductory and advanced programming courses. Furthermore, we also interpret from our findings a suggested model of a repeated cycle of lecture, demo and exercise as highly beneficial to the student learning process

Latency Thresholds for Usability in Games: A Survey

User interactions in interactive applications are time critical operations;late response will degrade the experience. Sensitivity to delay doeshowever vary greatly with between games. This paper surveys existingliterature on the specifics of this limitation. We find a classificationwhere games are grouped with others of roughly the same requirements.In addition we find some numbers on how long latency is acceptable.These numbers are however inconsistent between studies, indicatinginconsistent methodology or insufficient classification of games andinteractions. To improve classification, we suggest some changes.In general, research is too sparse to draw any strong or statisticallysignificant conclusions. In some of the most time critical games, latencyseems to degrade the experience at about 50 ms

Thirty Years of NIK: A Bibliometric Study of Paper Impact and Changes in Publication Patterns

The Norwegian Annual Informatics Conference (NIK) has served as the most important national meeting point for the academic community in Norway during the last thirty years. National conferences often have a reputation of being of lesser quality than international conferences. Yet, NIK have practiced peer review with relatively low acceptance rates which is a trait of quality. Based on the assumption that quality and impact are related, this study set out to explore the actual impact of NIK in terms of citations over its thirty-year lifetime. As NIK is not being systematically indexed there are no readily available source of citation data and these were thus manually extracted. The results show that NIK papers do get cited at a level comparable to reputable international conferences, and the ratio of papers that are cited is increasing. The results also show that the title length and the number of authors per paper have increased, whereas papers written in Norwegian do not get cited

Comprehensive Analysis of Innovative Cross-Platform App Development Frameworks

Mobile apps are increasingly realized by using a cross-platform development framework. Using such frameworks, code is written once but the app can be deployed to multiple platforms. Despite progress in research on cross-platform techniques, results (i.e. apps) are not always satisfactory. They are subject to tedious tailoring and the development effort tends to be notable. In these cases, either pure web apps (realized through web browsers) or native apps (realized for each platform separately) are chosen. Recent activities have led to new approaches. In this paper, we have a closer look at three of these, namely React Native, the Ionic Framework, and Fuse. We present a comprehensive analysis of the three approaches. Our work is based on a real-world use case, which allows us to provide generalizable advice. Our findings suggest that there is no clear winner; the frameworks incorporate notable ideas and general progress in the field can be asserted

A round-robin study of cellulose pyrolysis kinetics by thermogravimetry

Eight European laboratories with access to five different thermogravimetric analyzers participated in this round-robin study of Avicel PH-105 cellulose pyrolysis at 5 and 40 °C/min. Agreement between the laboratories on the temperature (Tpeak) associated with the maximum rate of weight loss at 5 °C/min was good. Less agreement was obtained on the residual char yield. At 40 °C/min, the scatter associated with measurements of Tpeak and the char yield increased. Good fits to each weight loss curve were obtained by use of a kinetic model based on an irreversible, first order reaction with a high (ca. 244 kJ/mol) apparent activation energy (E). Variations in values of E and the pre-exponential constant (A) are attributed to variations in thermal lag between the various instruments, and at different heating rates. Kinetic parameters are presented which offer a good fit to the 5 °C/min round-robin data, and which prescribe an envelope that contains the data. We recommend that future studies of biomass pyrolysis by thermogravimetry include an analysis of Avicel PH 105 cellulose at 5 °C/min, and a comparison of the resulting weight loss curve with the curves presented herein

Unconsciously Influential. Understanding sociotechnical Influence on social media

Over the last two decades, the rise of social media platforms such as Instagram, YouTube, and TikTok has sparked a global shift in commercial practices worldwide. People are exposed to and influenced by massive amounts of commercial content carefully and strategically integrated into these platforms’ social content. In addition, due to network structures, people’s engagement in the form of likes, comments, and simply viewing content results in the influence of people within and outside their network. In this study, we adopt a sociotechnical perspective and study the interplay between social and technical components in how influence is exercised on social media. Specifically, we identify the actors involved in the influence of commercial content and analyse how they exercise their influence for commercial purposes. Based on our findings and analysis, we present three contributions to Information systems literature: (1) how people have become unconsciously influential in spreading commercial content, which is the premise for social media commercial success, (2) how people’s social and commercial lives and contents are increasingly intertwined and (3) how this interweaving effect removes peoples’ ability to reflect on the content they engage with critically. Our study draws attention to the societal outcomes caused by technologies in practice

Effects of sample origin, extraction and hot water washing on the devolatilization kinetics of chestnut wood

The variations in chemical composition and the effects of sample origin and pre-treatments represent a major problem in the kinetic modeling of wood pyrolysis. This study aims to a deeper understanding of these issues by examining a species, chestnut (Castanea sativa), that contains a higher amount of extractives than the common forest hardwoods of the temperate zone. Thermogravimetric and kinetic analysis were carried out on five chestnut samples obtained from plants grown in France, Italy and Russia. The results were compared to that of a widely used and investigated species (beech) belonging to the same plant family. Degradation takes place over a narrower range and at lower temperatures, giving higher yields of char. In all cases, hot water washing causes a decrease in the fixed carbon content and char yield, an increase in the peak rate, a better separation between pseudo-component dynamics and a displacement of the reaction zones toward higher temperatures. Though with some scatter and quantitatively lower, the same effects are also observed as a consequence of acetone extraction. Both pre-treatments act to reduce the differences between chestnut samples and with beech, but peculiarities due to origin and species are preserved. The three parallel reaction mechanism for the hemicellulose, cellulose and lignin, with the same activation energies previously determined for other hardwood species by Grønli et al. (Ind. Eng. Chem. Res. 2002, 41, 4201) is still acceptable for engineering applications. On the contrary, predictions of the process details require single curves evaluations, resulting in kinetic data specific to sample origin, except for the activation energy of the lignin devolatilization step. Kinetic parameters also indicate that the lower char yields, associated with pre-treatments, are chiefly due to alterations in the cellulose decomposition kinetics, whereas the effects on the other two components nearly compensate each other. Finally, reliable evaluations are provided of experimental uncertainties associated with repeatability of experiments and reproducibility of sample properties

Immutable Infrastructure Calls for Immutable Architecture

With the advent of cloud computing and the concept of immutable infrastructure, the scaling and deployment of applications has become significantly easier. This increases the possibility of “configuration drift” as an operations team manages this cluster of machines, both virtual and actual. In this paper we propose a revised view on configuration and architecture. We propose that software deployed on a public or private cloud should, to the furthest possible extent, be immutable and source controlled. This reduces configuration drift and ensures no configuration problems in production as a result of updates or changes. We will show an example of a software project deployed on Amazon Web Services with an immutable Jenkins setup which manages updating the whole cluster and is self-regenerating. We will also discuss how this lends itself naturally to interoperability between clouds, because of the infrastructure-agnostic nature of this approach