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  • Journal article
    Colasanto L, Kormushev P, Tsagarakis N, Caldwell DGet al., 2012,

    Optimization of a compact model for the compliant humanoid robot COMAN using reinforcement learning

    , International Journal of Cybernetics and Information Technologies, Vol: 12, Pages: 76-85, ISSN: 1311-9702

    COMAN is a compliant humanoid robot. The introduction of passive compliance in some of its joints affects the dynamics of the whole system. Unlike traditional stiff robots, there is a deflection of the joint angle with respect to the desired one whenever an external torque is applied. Following a bottom up approach, the dynamic equations of the joints are defined first. Then, a new model which combines the inverted pendulum approach with a three-dimensional (Cartesian) compliant model at the level of the center of mass is proposed. This compact model is based on some assumptions that reduce the complexity but at the same time affect the precision. To address this problem, additional parameters are inserted in the model equation and an optimization procedure is performed using reinforcement learning. The optimized model is experimentally validated on the COMAN robot using several ZMP-based walking gaits.
  • Journal article
    Howey DA, Childs PRN, Holmes AS, 2012,

    Air-gap convection in rotating electrical machines

    , IEEE Transactions on Industrial Electronics, Vol: 59, Pages: 1367-1375, ISSN: 0278-0046

    This paper reviews convective heat transfer within the air-gap of both cylindrical and disc geometry rotating electrical machines, including worked examples relevant to fractional horsepower electrical machines. Thermal analysis of electrical machines is important because torque density is limited by maximum temperature. Knowledge of surface convective heat transfer coefficients is necessary for accurate thermal modelling for example using lumped parameter models. There exists a wide body of relevant literature, but much of it has traditionally been in other application areas, dominated by mechanical engineers, such as gas turbine design. Particular attention is therefore given to the explanation of the relevant non-dimensional parameters, and to the presentation of measured convective heat transfer correlations for a wide variety of situations from laminar to turbulent flow at small and large gap sizes for both radial flux and axial flux electrical machines.
  • Journal article
    Trombe P-J, Pinson P, Madsen H, 2012,

    A General Probabilistic Forecasting Framework for Offshore Wind Power Fluctuations

    , ENERGIES, Vol: 5, Pages: 621-657
  • Journal article
    Myant CW, Fan T, Underwood R, cann Pet al., 2012,

    Synovial Fluid Lubrication of Artificial Joints: Protein Film Formation and Composition

    , Faraday Discussions, ISSN: 1364-5498
  • Conference paper
    Childs PRN, Fountain R, 2012,

    Commercivity

    , 13th International Conference on Engineering and Product Design Education, Publisher: The Design Society, Pages: 3-8
  • Book
    Liu Z, Zhao C, Hall A, Childs Pet al., 2012,

    GoGlobal – Rural-Urban

    , Publisher: Waterpub, ISBN: 9787508494234
  • Journal article
    Steer SJ, Cardin M-A, Nuttall WJ, Parks GT, Goncalves LVNet al., 2012,

    Minimising the economic cost and risk to accelerator-driven subcritical reactor technology: The case of designing for flexibility: Part 1

    , NUCLEAR ENGINEERING AND DESIGN, Vol: 243, Pages: 135-147, ISSN: 0029-5493
  • Journal article
    Cardin M-A, Steer SJ, Nuttall WJ, Parks GT, Goncalves LVN, de Neufville Ret al., 2012,

    Minimizing the economic cost and risk to Accelerator-Driven Subcritical Reactor technology. Part 2: The case of designing for flexibility

    , NUCLEAR ENGINEERING AND DESIGN, Vol: 243, Pages: 120-134, ISSN: 0029-5493
  • Journal article
    Comin A, Korobchevskaya K, George C, Diaspro A, Manna Let al., 2012,

    Plasmon Bleaching Dynamics in Colloidal Gold-Iron Oxide Nanocrystal Heterodimers

    , NANO LETTERS, Vol: 12, Pages: 921-926, ISSN: 1530-6984
    • Cite
    • Citations: 33
  • Journal article
    Wu B, Matian M, Offer GJ, 2012,

    Hydrogen PEMFC system for automotive applications

    , International Journal of Low Carbon Technologies

    A balance of plant (BOP) system for a 9.5-kWe Nedstack P9.5-75 low-temperature proton exchange membrane fuel cell (FC) stack was tested up to a power of 2 kWe. The system has been designed to act as a range extender for a series hybrid electric vehicle driven under urban duty cycles. Vehicle simulations have estimated that an average gross power requirement of 4 kWe is needed from the FC, whilst simulations of the FC stack and BOP components have allowed for characterisation of transient behaviour and performance degradation.
  • Book
    Kormushev P, Olson E, Saxena A, Takano Wet al., 2012,

    Preface
  • Conference paper
    Hussain MS, Monkaresi H, Calvo RA, 2012,

    Combining classifiers in multimodal affect detection

    , Pages: 103-108, ISSN: 1445-1336

    Affect detection where users' mental states are automatically recognized from facial expressions, speech, physiology and other modalities, requires accurate machine learning and classification techniques. This paper investigates how combined classifiers, and their base classifiers, can be used in affect detection using features from facial video and multichannel physiology. The base classifiers evaluated include function, lazy and decision trees; and the combined where implemented as vote classifiers. Results indicate that the accuracy of affect detection can be improved using the combined classifiers especially by fusing the multimodal features. The base classifiers that are more useful for certain modalities have been identified. Vote classifiers also performed best for most of the individuals compared to the base classifiers.
  • Conference paper
    Liu M, Calvo RA, Rus V, 2012,

    Hybrid question generation approach for critical review writing support

    , Pages: 109-111

    Research towards automated feedback can build on the work in other areas. In this paper we explore question generation techniques. Most research in question generation has focused on generating content specific questions that help students comprehend a set of documents that they must read. However, this approach is not so useful in writing activities, as students would generally understand the document that they themselves wrote. The aim of our project is to build a system which automatically generates feedback questions for academic writing support, particularly for critical review support. This paper presents our question generation system which relies on both syntax-based and template-based approaches, and uses Wikipedia as background knowledge.
  • Conference paper
    Monkaresi H, Hussain MS, Calvo RA, 2012,

    A dynamic approach for detecting naturalistic affective states from facial videos during HCI

    , Pages: 170-181, ISSN: 0302-9743

    Significant progress has been made in automatic facial expression analysis using facial images and videos. The recognition reliability of most current approaches is still poor in naturalistic expressions compared to acted ones. Most of these methods use a static image of each expression that captures the characteristic image at the apex. However, according to psychologists, analyzing a sequence of images in a dynamic manner produces more accurate and robust recognition of facial affect expressions. In this paper, a new dynamic model is proposed for detecting naturalistic affect expressions. The Local Binary Pattern in Three Orthogonal Planes (LBP-TOP) is considered for modeling appearance and motion of facial features. The International Affective Picture System (IAPS) collection was used as stimulus for triggering naturalistic affective states. The dynamic approach produced an improvement of 16% for valence classification and 22% for arousal classification over previous studies. © 2012 Springer-Verlag.
  • Conference paper
    Picinali L, Feakes C, Mauro DA, Katz BFGet al., 2012,

    Spectral discrimination thresholds comparing audio and haptics for complex stimuli

    , Pages: 131-140, ISSN: 0302-9743

    Individuals with normal hearing are generally able to discriminate auditory stimuli that have the same fundamental frequency but different spectral content. This study concerns to what extent it is possible to perform the same differentiation considering vibratory tactile stimuli. Three perceptual experiments have been carried out in an attempt to compare discrimination thresholds in terms of spectral differences between auditory and vibratory tactile stimulations. The first test consists of assessing the subject’s ability in discriminating between three signals with distinct spectral content. The second test focuses on the measurement of the discrimination threshold between a pure tone signal and a signal composed of two pure tones, varying the amplitude and frequency of the second tone. Finally, in the third test the discrimination threshold is measured between a tone with even harmonic components and a tone with odd ones. The results show that it is indeed possible to discriminate between haptic signals having the same fundamental frequency but different spectral. The threshold of sensitivity for detection is markedly less than for audio stimuli.
  • Journal article
    Lancheros S, Demirel P, 2012,

    Does Finance Play a Role in Exporting for Service Firms? Evidence from India

    , WORLD ECONOMY, Vol: 35, Pages: 44-60, ISSN: 0378-5920
  • Journal article
    De Trizio L, Figuerola A, Manna L, Genovese A, George C, Brescia R, Saghi Z, Simonutti R, Van Huis M, Falqui Aet al., 2012,

    Size-Tunable, Hexagonal Plate-like Cu<sub>3</sub>P and Janus-like Cu-Cu<sub>3</sub>P Nanocrystals

    , ACS NANO, Vol: 6, Pages: 32-41, ISSN: 1936-0851
    • Cite
    • Citations: 92
  • Journal article
    Villegas C, Corless M, Griggs W, Shorten Ret al., 2012,

    A Passivity Based Decentralized Control Design Methodology With Application to Vehicle Dynamics Control

    , JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND CONTROL-TRANSACTIONS OF THE ASME, Vol: 134, ISSN: 0022-0434
  • Conference paper
    Monkaresi H, Calvo RA, Hussain MS, 2012,

    Automatic Natural Expression Recognition using Head Movement and Skin Color Features

    , International Working Conference on Advanced Visual Interfaces (AVI), Publisher: ASSOC COMPUTING MACHINERY, Pages: 657-660
  • Journal article
    Dilena E, Dorfs D, George C, Miszta K, Povia M, Genovese A, Casu A, Prato M, Manna Let al., 2012,

    Colloidal Cu<sub>2-<i>x</i></sub>(S<i><sub>y</sub></i>Se<sub>1-<i>y</i></sub>) alloy nanocrystals with controllable crystal phase: synthesis, plasmonic properties, cation exchange and electrochemical lithiation

    , JOURNAL OF MATERIALS CHEMISTRY, Vol: 22, Pages: 13023-13031, ISSN: 0959-9428
  • Conference paper
    Chew WT, Astolfi A, Ming X, 2012,

    Robust Control of Bipedal Humanoid (TPinokio)

    , International Symposium on Robotics and Intelligent Sensors (IRIS), Publisher: ELSEVIER SCIENCE BV, Pages: 643-649, ISSN: 1877-7058
  • Conference paper
    Egwutuoha IP, Chen S, Levy D, Selic B, Calvo Ret al., 2012,

    A Proactive Fault Tolerance Approach to High Performance Computing (HPC) in the Cloud

    , 2nd International Conference on Cloud and Green Computing / 2nd International Conference on Social Computing and its Applications (CGC/SCA), Publisher: IEEE, Pages: 268-273
  • Conference paper
    Monkaresi H, Hussain MS, Calvo RA, 2012,

    Classification of Affects Using Head Movement, Skin Color Features and Physiological Signals

    , IEEE International Conference on Systems, Man, and Cybernetics (SMC), Publisher: IEEE, Pages: 2664-2669, ISSN: 1062-922X
  • Journal article
    Eastwood D, Coren DD, Long CA, Atkins NR, Childs PRN, Scanlon TJ, Guijarro-Valencia Aet al., 2012,

    Experimental Investigation of Turbine Stator Well Rim Seal, Re-Ingestion and Interstage Seal Flows Using Gas Concentration Techniques and Displacement Measurements

    , Journal of Engineering for Gas Turbines and Power-Transactions of the ASME, Vol: 134, Pages: 082501-1-082501-9

    Gas turbine engine performance requires effective and reliable internal cooling over theduty cycle of the engine. Life predictions for rotating components subject to the main gaspath temperatures are vital. This demands increased precision in the specification of theinternal air system flows which provide turbine stator well cooling and sealing. This inturn requires detailed knowledge of the flow rates through rim seals and interstage labyrinthseals. Knowledge of seal movement and clearances at operating temperatures is ofgreat importance when prescribing these flows. A test facility has been developed atthe University of Sussex, incorporating a two stage turbine rated at 400 kW with anindividual stage pressure ratio of 1.7:1. The mechanical design of the test facility allowsinternal cooling geometry to be rapidly re-configured, while cooling flow rates ofbetween 0.71 CW, ENT and 1.46 CW, ENT, may be set to allow ingress or egress dominatedcavity flows. The main annulus and cavity conditions correspond to in cavity rotationalReynolds numbers of 1.71 106< Reu<1.93 106. Displacement sensors have beenused to establish hot running seal clearances over a range of stator well flow conditions,allowing realistic flow rates to be calculated. Additionally, gas seeding techniques havebeen developed, where stator well and main annulus flow interactions are evaluated bymeasuring changes in gas concentration. Experiments have been performed which allowrim seal and re-ingestion flows to be quantified. It will be shown that this work developsthe measurement of stator well cooling flows and provides data suitable for the validationof improved thermo-mechanical and CFD codes, beneficial to the engine design process.
  • Journal article
    Childs PRN, Hall A, Teasley S, 2012,

    Design thinking, the third culture of design

    , Design Issues

    In response to CP Snow’s consideration of the separations of the cultures of the arts andhumanities from the sciences and numeracy, Bruce Archer in the 1970s suggested that designrepresented a third and distinct culture. More recently the distinct processes associated withdesign thinking have been explored, with the identification of the importance of abductivereasoning in design. However the identification of distinctively ‘design’ ways of thinking andproposals for their application outside the design industries have an earlier history, one thatsuggests a link between design thinking, creativity and moments of economic andinfrastructural change. This paper draws together contemporary and historical considerationsof design culture, design thinking and creativity research. Recognising design as a distinctthird culture highlights its value as an increasingly important element of global economicprosperity. Understanding its core thinking structure can provide guidance to both educatorsand practising designers in prioritising training and design activity. It is concluded that theframing of design thinking and its translation to other disciplines has now provided a richsource of experiences that feeds back into the design disciplines, enabling the culture ofdesign to further develop.
  • Journal article
    Deken F, Kleinsmann M, Aurisicchio M, Lauche K, Bracewell RHet al., 2012,

    Tapping into past design experiences: knowledge sharing and creation during novice-expert design consultations

    , Research in Engineering Design, Vol: 23, Pages: 203-218

    Designing is a knowledge-intensive activity. For novice design engineers, an important means of acquiring knowledge is to consult experienced colleagues. We observed novice–expert consultations as part of three engineering projects in a large aerospace company. Seven meetings were analysed in detail regarding the design activity, the content, and the form of interaction. Although the meetings were initiated for the purpose of information seeking , this process amounted to only 8% of the time compared to knowledge creation between novices and experts (47% of meeting time), and contextual information sharing (45% of meeting time). Both experts and novices were found to contribute equally and interactively to the discussion and analysis of solutions. The analysis showed how the processes alternated in the meetings. We identified tentative patterns on how these consultation processes change over the course of the design process phases. The micro-level analysis of the design activities and form of interaction provided a deeper understanding of how the consultation processes are discursively produced by the experts and novices. Finally, implications for design engineering practitioners are derived and suggestions for further research are provided.
  • Journal article
    Porat T, Tractinsky N, 2012,

    It's a Pleasure Buying Here: The Effects of Web-Store Design on Consumers' Emotions and Attitudes

    , HUMAN-COMPUTER INTERACTION, Vol: 27, Pages: 235-276, ISSN: 0737-0024
  • Journal article
    Demirel P, Mazzucato M, 2012,

    Innovation and Firm Growth: Is R&D Worth It?

    , INDUSTRY AND INNOVATION, Vol: 19, Pages: 45-62, ISSN: 1366-2716
  • Journal article
    Dallali H, Kormushev P, Li Z, Caldwell DGet al., 2012,

    On Global Optimization of Walking Gaits for the Compliant Humanoid Robot COMAN Using Reinforcement Learning

    , International Journal of Cybernetics and Information Technologies, Vol: 12
  • Journal article
    Leonetti M, Kormushev P, Sagratella S, 2012,

    Combining Local and Global Direct Derivative-free Optimization for Reinforcement Learning

    , International Journal of Cybernetics and Information Technologies, Vol: 12

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