Corless M.,Purdue University |
Shorten R.,NUI Maynooth Co.
International Journal of Control | Year: 2012
In this article we propose a version of the Additive-Increase Multiplicative-Decrease (AIMD) algorithm that provides a suitable basis to develop congestion control protocols that can be deployed in both conventional and high-speed communication networks. Our algorithm retains many of the properties of the standard AIMD algorithm. However, unlike other non-standard AIMD algorithms, our scheme can be shown to be ergodic under very general assumptions. © 2012 Taylor & Francis.
Batty M.,University College London |
Axhausen K.W.,ETH Zurich |
Giannotti F.,University of Pisa |
Pozdnoukhov A.,NUI Maynooth Co. |
And 4 more authors.
European Physical Journal: Special Topics | Year: 2012
Here we sketch the rudiments of what constitutes a smart city which we define as a city in which ICT is merged with traditional infrastructures, coordinated and integrated using new digital technologies. We first sketch our vision defining seven goals which concern: developing a new understanding of urban problems; effective and feasible ways to coordinate urban technologies; models and methods for using urban data across spatial and temporal scales; developing new technologies for communication and dissemination; developing new forms of urban governance and organisation; defining critical problems relating to cities, transport, and energy; and identifying risk, uncertainty, and hazards in the smart city. To this, we add six research challenges: to relate the infrastructure of smart cities to their operational functioning and planning through management, control and optimisation; to explore the notion of the city as a laboratory for innovation; to provide portfolios of urban simulation which inform future designs; to develop technologies that ensure equity, fairness and realise a better quality of city life; to develop technologies that ensure informed participation and create shared knowledge for democratic city governance; and to ensure greater and more effective mobility and access to opportunities for urban populations.We begin by defining the state of the art, explaining the science of smart cities. We define six scenarios based on new cities badging themselves as smart, older cities regenerating themselves as smart, the development of science parks, tech cities, and technopoles focused on high technologies, the development of urban services using contemporary ICT, the use of ICT to develop new urban intelligence functions, and the development of online and mobile forms of participation. Seven project areas are then proposed: Integrated Databases for the Smart City, Sensing, Networking and the Impact of New Social Media, Modelling Network Performance, Mobility and Travel Behaviour, Modelling Urban Land Use, Transport and Economic Interactions, Modelling Urban Transactional Activities in Labour and Housing Markets, Decision Support as Urban Intelligence, Participatory Governance and Planning Structures for the Smart City. Finally we anticipate the paradigm shifts that will occur in this research and define a series of key demonstrators which we believe are important to progressing a science of smart cities.© The Author(s) 2012.
de Lima M.H.,Rua Edelberto de Oliveira |
Keller D.,Federal University of Acre |
Pimenta M.S.,Federal University of Rio Grande do Sul |
Lazzarini V.,NUI Maynooth Co. |
Journal of Music, Technology and Education | Year: 2012
This study is among the first that attempt to define a methodology for creativity-centred software design in educational contexts, more specifically for musical activities in ubiquitous settings. We propose and apply a set of design techniques - the Ubimus Planning and the Ubimus Design protocols - as alternatives to experimental procedures that leave out relevant aspects of social and procedural dimensions in educational research. Two workshops were conducted to assess both technological and domainspecific requirements for support of creative musical activities. The first workshop was conducted with music teachers and school teachers that had no formal musical training. The objective of this workshop was to assess domain-specific requirements for musical creative activities by educational staff. The second workshop focused on technological support for tool development by non-musicians. This workshop yielded two software projects that involved user evaluations of creative processes. Participants in the corresponding user studies included both musicians and non-musicians. The Ubimus Planning protocol served to raise important questions regarding technological usage by musicians and naive subjects in educational contexts. Non-technical approaches, such as those proposed by traditional soundscape activities, may not be suited for introducing non-musicians to sonic composition. Naive subjects may respond better to technologically based approaches, such as those used in ecocomposition. The Ubimus Design approach proved to be effective to test the usability of musical tools at early stages of development. Prototypes were implemented and usability studies were carried out by undergraduate IT students within a three-week time slot. Sharp differences were observed in the type of requirements expressed by musicians and non-musicians regarding creativity support tools. Nevertheless, both groups of subjects assessed the use of software prototypes within exploratory musical activities as being fun and expressive. © 2012 Intellect Ltd Article.
Martin J.S.,Technical University of Madrid |
Martin J.S.,Spanish University for Distance Education (UNED) |
O'Farrell A.G.,NUI Maynooth Co.
International Journal of Adaptive Control and Signal Processing | Year: 2013
We report conditions on a switching signal that guarantee that solutions of a switched linear system converge asymptotically to zero. These conditions apply to continuous, discrete-time and hybrid switched linear systems, those having both stable subsystems and mixtures of stable and unstable subsystems. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.
Medioli A.,University of Newcastle |
Seron M.,University of Newcastle |
Middleton R.,NUI Maynooth Co.
Automatica | Year: 2011
The null controllable set of a system is the largest set of states that can be controlled to the origin. Control systems that have a region of attraction equal to the null controllable set are said to be maximally controllable closed-loop systems. In the case of open-loop unstable plants with amplitude constrained control it is well known that the null controllable set does not cover the entire state-space. Further the combination of input constraints and unstable system dynamics results in a set of state constraints which we call implicit constraints. It is shown that the simple inclusion of implicit constraints in a controller formulation results in a controller that achieves maximal controllability for a class of open-loop unstable systems. © 2011 Elsevier Ltd. All rights reserved.