Optimal configuration of active and backup servers for augmented reality cooperative games

Interactive applications as online games and mobile devices have become more and more popular in recent years. From their combination, new and interesting cooperative services could be generated. For instance, gamers endowed with Augmented Reality (AR) visors connected as wireless nodes in an ad-hoc network, can interact with each other while immersed in the game. To enable this vision, we discuss here a hybrid architecture enabling game play in ad-hoc mode instead of the traditional client-server setting. In our architecture, one of the player nodes also acts as the server of the game, whereas other backup server nodes are ready to become active servers in case of disconnection of the network i.e. due to low energy level of the currently active server. This allows to have a longer gaming session before incurring in disconnections or energy exhaustion. In this context, the server election strategy with the aim of maximizing network lifetime is not so straightforward. To this end, we have hence analyzed this issue through a Mixed Integer Linear Programming (MILP) model and both numerical and simulation-based analysis shows that the backup servers solution fulfills its design objective

Tactor devices : using tactile interface designs for mobile digital appliances : a practice-based research thesis for the fulfilment of a Master of Design degree, College of Design, Fine Arts, and Music, Massey University, Wellington

This Thesis focuses the potential of communication interfaces that use tactors (tactile actuators) to improve user interactions with mobile digital devices which are currently based on audio and visual technologies. It presents two product concepts, which use tactile signals to enable new ways in tele-operations, such as tactile telecommunication and tactile navigation. Tactor interfaces, although still in its infancy as elements of modern digital communication and technology, have considerable potential for the future as designers attempt to maximise the use of all human senses in people's interaction with technology. Only the military and a few entertainment companies have introduced tactile signals into Human-Computer Interactions (HCI). Human touch perception uses the hands as the main sensing organs. They perceive tactile signals while handling, typing or navigating with digital devices and receive direct confirmation of physical actions. In contrast to other senses, touch perceptions are based on interactions with the sensed objects. The study analyses, experiments and evaluates if these interactions are useful in interface designs and recommends how tactile stimulations can be introduced to interface designs besides images and sounds that dominate the control of current digital appliances. Tactile actuators and sensors enable devices to use tactile signals, such as impulses and vibrations, to communicate with the users. Users and tactor devices will be able to communicate in a physical and direct way. Touch reflective interfaces, could react like living creatures that respond to touch, for example a cat that starts purring when touched. Digital product design is always challenged to create human-computer interactions that meet people's needs. Designing digital devices is difficult because they are not necessarily three-dimensional objects. They are stimulator of the human senses and can be as small as the sensing nerve endings that detect sensations. By miniaturisation, form and function become invisible and Product Design is increasingly incorporating Process Design that explores and enables new interactions between users and products to work interactively and efficiently. The study is divided into four chapters: Chapter 1 gives an introduction to the thesis. Chapter 2 presents a survey on current literature which examines the five human senses to define the limits and possibilities in interface design. It reviews current research on materials and technologies as well as the psychology and physiology of touch as a potential sense in human-computer interactions. It evaluates the technical feasibilty of tactile signal performances and how they could be used as tele-touch codes in navigation and telecommunication. Chapter 3 is focused on primary research undertaken to extend the knowledge in tactile sensing. It includes experiments, questionnaires, and concepts that give examples how tactor interfaces can be used in tele-operations. This section focuses on specific user groups, that may primarily benefit from tactile signal transmissions, such as sight and hearing-impaired people or professionals who have to deal with limited perceptions like fire fighters, for example. These case studies are aimed at exploring and expanding a wider range of possibilities in tactile device innovations in the networked society. Chapter 4 gives a conclusion of the research

Context Aware Computing for The Internet of Things: A Survey

As we are moving towards the Internet of Things (IoT), the number of sensors deployed around the world is growing at a rapid pace. Market research has shown a significant growth of sensor deployments over the past decade and has predicted a significant increment of the growth rate in the future. These sensors continuously generate enormous amounts of data. However, in order to add value to raw sensor data we need to understand it. Collection, modelling, reasoning, and distribution of context in relation to sensor data plays critical role in this challenge. Context-aware computing has proven to be successful in understanding sensor data. In this paper, we survey context awareness from an IoT perspective. We present the necessary background by introducing the IoT paradigm and context-aware fundamentals at the beginning. Then we provide an in-depth analysis of context life cycle. We evaluate a subset of projects (50) which represent the majority of research and commercial solutions proposed in the field of context-aware computing conducted over the last decade (2001-2011) based on our own taxonomy. Finally, based on our evaluation, we highlight the lessons to be learnt from the past and some possible directions for future research. The survey addresses a broad range of techniques, methods, models, functionalities, systems, applications, and middleware solutions related to context awareness and IoT. Our goal is not only to analyse, compare and consolidate past research work but also to appreciate their findings and discuss their applicability towards the IoT.Comment: IEEE Communications Surveys & Tutorials Journal, 201

A Benchmark for Image Retrieval using Distributed Systems over the Internet: BIRDS-I

The performance of CBIR algorithms is usually measured on an isolated workstation. In a real-world environment the algorithms would only constitute a minor component among the many interacting components. The Internet dramati-cally changes many of the usual assumptions about measuring CBIR performance. Any CBIR benchmark should be designed from a networked systems standpoint. These benchmarks typically introduce communication overhead because the real systems they model are distributed applications. We present our implementation of a client/server benchmark called BIRDS-I to measure image retrieval performance over the Internet. It has been designed with the trend toward the use of small personalized wireless systems in mind. Web-based CBIR implies the use of heteroge-neous image sets, imposing certain constraints on how the images are organized and the type of performance metrics applicable. BIRDS-I only requires controlled human intervention for the compilation of the image collection and none for the generation of ground truth in the measurement of retrieval accuracy. Benchmark image collections need to be evolved incrementally toward the storage of millions of images and that scaleup can only be achieved through the use of computer-aided compilation. Finally, our scoring metric introduces a tightly optimized image-ranking window.Comment: 24 pages, To appear in the Proc. SPIE Internet Imaging Conference 200

A Survey of Green Networking Research

Reduction of unnecessary energy consumption is becoming a major concern in wired networking, because of the potential economical benefits and of its expected environmental impact. These issues, usually referred to as "green networking", relate to embedding energy-awareness in the design, in the devices and in the protocols of networks. In this work, we first formulate a more precise definition of the "green" attribute. We furthermore identify a few paradigms that are the key enablers of energy-aware networking research. We then overview the current state of the art and provide a taxonomy of the relevant work, with a special focus on wired networking. At a high level, we identify four branches of green networking research that stem from different observations on the root causes of energy waste, namely (i) Adaptive Link Rate, (ii) Interface proxying, (iii) Energy-aware infrastructures and (iv) Energy-aware applications. In this work, we do not only explore specific proposals pertaining to each of the above branches, but also offer a perspective for research.Comment: Index Terms: Green Networking; Wired Networks; Adaptive Link Rate; Interface Proxying; Energy-aware Infrastructures; Energy-aware Applications. 18 pages, 6 figures, 2 table

Industrial Fieldbus Improvements in Power Distribution and Conducted Noise Immunity With No Extra Costs

Industrial distributed control continues the move toward networks at all levels. At lower levels, control networks provide flexibility, reliability, and low cost, although perhaps the simplest but most important advantage is the reduced volume of wiring. Powered fieldbuses offer particular notable benefits in system wiring simplification. Nevertheless, very few papers are dealing with the potentials and limitations in power distribution through the bus cable. Only a few of the existent fieldbus standards consider this possibility but often simply as an option without enough technical specifications. In fact, nobody talks about it, but power distribution through the bus and conducted noise disturbances are strongly related. This paper points out and analyzes these limitations and proposes a new low-cost fieldbus physical layer that enlarges power distribution capability of the bus and improves system robustness. We show an industrial application on water desalination plants and the very good results obtained owing to the fieldbus. Finally, we present electromagnetic compatibility test results that verify improvements against electrical fast transients on the sensor/actuator connection side as disturbances usually encountered in harsh-environment industrial applications