To Örebro University

oru.seÖrebro University Publications
Change search
Refine search result
3456789 251 - 300 of 1393
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 251.
    Carlson, Jan
    et al.
    Department of Computer Science and Engineering, Mälardalen University, Västerås, Sweden.
    Lennvall, Tomas
    Department of Computer Science and Engineering, Mälardalen University, Västerås, Sweden.
    Fohler, Gerhard
    Department of Computer Science and Engineering, Mälardalen University, Västerås, Sweden.
    Enhancing time triggered scheduling with value based overload handling and task migration2003In: Sixth IEEE International Symposium on Object-Oriented Real-Time Distributed Computing, 2003: Proceedings, IEEE Computer Society, 2003, p. 121-128Conference paper (Refereed)
    Abstract [en]

    Time triggered methods provide deterministic behaviour suitable for critical real-time systems. The), perform less favourably, however if the arrival times of some activities are not known in advance, in particular if overload situations have to be anticipated. In many systems, the criticality of only a subset of activities justify the cost associated with the time triggered methods.

    In this paper we consider distributed systems where a subset of critical activities are handled in a time triggered fashion, via an offline schedule. At runtime, the arrival of aperiodic tasks may cause overload that demands to be handled in such a way that i) time triggered activities still meet all their original constraints, ii) execution of high-valued tasks are prioritised over tasks with lower value, iii) tasks can be quickly migrated to balance the overall system load.

    We give a precise formulation of overload detection and value based task rejection in the presence of offline scheduled tasks, and present a heuristic algorithm to handle overload. To benefit from the distributed setting, the overload handling includes an algorithm that integrates migration of rejected tasks with resource reclaiming and an acceptance test of newly arrived tasks.

    Simulation results underline the effectiveness of the presented approach.

  • 252.
    Carrascosa, Carlos
    et al.
    Universitat Politécnica de Valencia, Valencia, Spain.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Ricci, Alessandro
    Universita di Bologna, Cesena, Italy.
    Virtual Environments 4 MAS2014In: E4MAS - 10 Years Later. Workshop at AAMAS 2014 / [ed] D. Weyns et al., 2014Conference paper (Refereed)
    Abstract [en]

    The environment is a key point when talking about MASapplications, being a key concept when developing a platform or appli-cation in the past ten years: what is important in it and how to access it.At the same time, technology has evolved so that Virtual Environment-kinds of applications have grown out of science ction novels till researchpapers and even real applications. Current technology makes possible toMAS to interact also in this environments.In this paper, we have looked for the common ground that have all thedierent domains relating Virtual Environments as E4MAS, and we havecharacterized those domains according to three dimensions: connectionto the physical world of the environment, agents nature, and sociability.Moreover, we comment one of these domains, Mirror Worlds, as it is oneof the most complex domains commented, that we believe that is one ofthe topics to take into account in the near future both as a researh anddeveloping domain.

  • 253.
    Carrascosa, Carlos
    et al.
    Departamento de Sistemas Informáticos y Computación (DSIC), Universitat Politècnica de València, Valencia, Spain.
    Klügl, Franziska
    Örebro University, School of Law, Psychology and Social Work.
    Ricci, Alessandro
    Dipartimento di Informatica - Scienza e Ingegneria (DISI), Alma Mater Studiorum Università di Bologna, Cesena, Italy.
    Boissier, Olivier
    Mines and Laboratoire Hubert Curien CNRS:UMR 5516, Institut Henri Fayol - Ecole Normale Supérieure (FAYOL - ENS), Saint-Etienne, France.
    From Physical to Virtual: Widening the Perspective on Multi-Agent Environments2015In: Agent Environments for Multi-Agent Systems IV, Springer, 2015, 1, p. 133-146Conference paper (Refereed)
    Abstract [en]

    Since more than a decade, the environment is seen as a key element when analyzing, developing or deploying Multi-Agent Systems (MAS) applications. Especially, for the development of multi-agent platforms, it has become a key concept, similarly to many application in the area of location-based, distributed systems. An emerging, prominent application area for MAS is related to Virtual Environments. The underlying technology has evolved in a way, that these applications have grown out of science fiction novels till research papers and even real applications. Even more, current technologies enable MAS to be key components of such virtual environments.

    In this paper, we widen the concept of the environment of a MAS to encompass new and mixed physical, virtual, simulated, etc. forms of environments. We analyze currently most interesting application domains based on three dimensions: the way different "realities" are mixed via the environment, the underlying natures of agents, the possible forms and sophistication of interactions. In addition to this characterization, we discuss how this widened concept of possible environments influences the support it can give for developing applications in the respective domains.

  • 254.
    Carretero Chavez, Willow
    et al.
    Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 9500 Gilman Dr, La Jolla, CA, 92093, USA; Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA.
    Krantz, Marcus
    Örebro University, School of Medical Sciences. Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115, Berlin, Germany; School of Medical Sciences and Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Klipp, Edda
    Theoretical Biophysics, Humboldt-Universität zu Berlin, Invalidenstr. 42, 10115, Berlin, Germany.
    Kufareva, Irina
    Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 9500 Gilman Dr, La Jolla, CA, 92093, USA.
    kboolnet: a toolkit for the verification, validation, and visualization of reaction-contingency (rxncon) models2023In: BMC Bioinformatics, E-ISSN 1471-2105, Vol. 24, no 1, article id 246Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Computational models of cell signaling networks are extremely useful tools for the exploration of underlying system behavior and prediction of response to various perturbations. By representing signaling cascades as executable Boolean networks, the previously developed rxncon ("reaction-contingency") formalism and associated Python package enable accurate and scalable modeling of signal transduction even in large (thousands of components) biological systems. The models are split into reactions, which generate states, and contingencies, that impinge on reactions; this avoids the so-called "combinatorial explosion" of system size. Boolean description of the biological system compensates for the poor availability of kinetic parameters which are necessary for quantitative models. Unfortunately, few tools are available to support rxncon model development, especially for large, intricate systems.

    RESULTS: We present the kboolnet toolkit ( https://github.com/Kufalab-UCSD/kboolnet , complete documentation at https://github.com/Kufalab-UCSD/kboolnet/wiki ), an R package and a set of scripts that seamlessly integrate with the python-based rxncon software and collectively provide a complete workflow for the verification, validation, and visualization of rxncon models. The verification script VerifyModel.R checks for responsiveness to repeated stimulations as well as consistency of steady state behavior. The validation scripts TruthTable.R, SensitivityAnalysis.R, and ScoreNet.R provide various readouts for the comparison of model predictions to experimental data. In particular, ScoreNet.R compares model predictions to a cloud-stored MIDAS-format experimental database to provide a numerical score for tracking model accuracy. Finally, the visualization scripts allow for graphical representations of model topology and behavior. The entire kboolnet toolkit is cloud-enabled, allowing for easy collaborative development; most scripts also allow for the extraction and analysis of individual user-defined "modules".

    CONCLUSION: The kboolnet toolkit provides a modular, cloud-enabled workflow for the development of rxncon models, as well as their verification, validation, and visualization. This will enable the creation of larger, more comprehensive, and more rigorous models of cell signaling using the rxncon formalism in the future.

  • 255.
    Cavallo, Filippo
    et al.
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Limosani, Raffaele
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Manzi, Alessandro
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Bonaccorsi, Manuele
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Esposito, Raffaele
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Di Rocco, Maurizio
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Teti, Giancarlo
    Robotech Srl, Peccioli, Italy.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Dario, Paolo
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Development of a socially believable multi-robot solution from town to home2014In: Cognitive Computation, ISSN 1866-9956, E-ISSN 1866-9964, Vol. 6, no 4, p. 954-967Article in journal (Refereed)
    Abstract [en]

    Technological advances in the robotic and ICT fields represent an effective solution to address specific societal problems to support ageing and independent life. One of the key factors for these technologies is that they have to be socially acceptable and believable to the end-users. This paper aimed to present some technological aspects that have been faced to develop the Robot-Era system, a multi-robotic system that is able to act in a socially believable way in the environments daily inhabited by humans, such as urban areas, buildings and homes. In particular, this paper focuses on two services-shopping delivery and garbage collection-showing preliminary results on experiments conducted with 35 elderly people. The analysis adopts an end-user-oriented perspective, considering some of the main attributes of acceptability: usability, attitude, anxiety, trust and quality of life.

  • 256. Cesta, Amedeo
    et al.
    Bahadori, Shahram
    Cortellessa, Gabriella
    Grisetti, Giorgio
    Giuliani, Vittoria
    Iocchi, Luca
    Leone, Riccardo G.
    Nardi, Daniele
    Oddi, Angelo
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Saggese, Anna
    Scopelliti, Massimiliano
    The RoboCare project, cognitive systems for the care of the elderly2003Conference paper (Refereed)
  • 257. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Giuliani, M. Vittoria
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Scopelliti, Massimiliano
    Tiberio, Lorenza
    The RoboCare project: the user’s view2008In: Aging, disability and independence: selected papers from the 4th international conference on aging, disability and independence / [ed] William C. Mann, IOS Press, 2008, p. 85-104Chapter in book (Refereed)
  • 258. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Giuliani, Vittoria
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Scopelliti, Massimiliano
    Tiberio, Lorenza
    Proactive assistive technology: an empirical study2007In: Human-Computer Interaction: INTERACT 2007 / [ed] Cécilia Calani Baranauskas, Philippe Palanque, Julio Abascal, Simone Diniz Junqueira Barbosa, Springer Berlin/Heidelberg, 2007, p. 255-268Conference paper (Refereed)
    Abstract [en]

    This paper analyzes the problem of evaluating elderly people’s perception of assistive robots and domotic environments. Specifically, we focus on aspects related to the modalities in which interaction can occur between an elder user and an assistive robotic agent. Our work benefits from the products of project RoboCare, namely, a domestic environment in which sensors, intelligent software components and a domestic robot provide a set of cognitive support services for the elder user. This paper analyzes a number of evaluation criteria in detail, specifically related to the robot’s aspect, the way in which it communicates with the user, and the perceived usefulness of its support services. Among these criteria, the paper proposes and reports an evaluation of the Proactive interaction modality (where the system takes the initiative) and On-demand interaction (in which the user explicitly requests a service). Users evaluate the On-demand support services in personal safety scenarios as particularly useful, and less so in scenarios which are not critical. The paper also provides a discussion which can be useful for the design of future assistive agents and robotic companions. This research is partially supported by MIUR (Italian Ministry of Education, University and Research) under project RoboCare (A Multi-Agent System with Intelligent Fixed and Mobile Robotic Components).

  • 259. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Giuliani, Vittoria
    Pecora, Federico
    Örebro University, Department of Technology.
    Scopelliti, Massimiliano
    Tiberio, Lorenza
    Caring about the user’s view: the joys and sorrows of experiments with people2007In: Proceedings of Workshop on Moving Planning and Scheduling Systems into the Real World at ICAPS'07, 2007Conference paper (Refereed)
  • 260. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Giuliani, Vittoria
    Pecora, Federico
    Örebro University, Department of Technology.
    Scopelliti, Massimiliano
    Tiberio, Lorenza
    Psychological implications of domestic assistive technology for the elderly2007In: PsychNology Journal, E-ISSN 1720-7525, Vol. 5, no 3, p. 229-252Article in journal (Refereed)
    Abstract [en]

    The ROBOCARE Domestic Environment (RDE) is the result of a three-year project aimed at developing cognitive support technology for elderly people. Specifically, the domestic environment is equipped with sensors, intelligent software components and devices which cooperate to provide cognitive support to the assisted person. The ROBOCARE interaction capabilities have been concentrated in a robotic mediator who acts as the main communication channel between the users and the intelligent domestic environment. This paper presents an evaluation of elderly people's perception of assistive robots and smart domotic environments. Results show how the acceptability of robotic devices in home setting does not depend only on the practical benefits they can provide, but also on complex relationships between the cognitive, affective and emotional components of people's images of robot. Specially, we analyzes a number of evaluation criteria related to the robot's aspect, the way in which it communicates with the user, and the perceived usefulness of its support services. Among these criteria, the paper proposes and reports an evaluation of how perceived frailty, with reference to both health in general and fear of cognitive weakening, more specifically, can influence the evaluation of a potential aid in everyday life, namely the robotic assistant. The paper also provides a discussion which can be useful for the design of future assistive agents and socially interactive robotic.

  • 261. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Coordinating heterogeneous agents to synthesize proactive monitoring2007In: Proceedings of Workshop on Planning and Plan Execution for Real-World Systems at ICAPS'07, 2007Conference paper (Refereed)
  • 262. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Intelligent supervision for ambient intelligence: customizing scheduling technology2005In: Proceedings of IEE Workshop on Intelligent Environments, 2005Conference paper (Refereed)
  • 263. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Mediating the knowledge of end-users and technologists: a problem in the deployment of scheduling technology2005In: Proceedings of IASTED International Conference on Artificial Intelligence and Applications, 2005Conference paper (Refereed)
  • 264. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Monitoring domestic activities with scheduling techniques2005In: RoboCare, RC-Ws-2: proceedings of the second RoboCare workshop / [ed] Amedeo Cesta, 2005, p. 31-38Conference paper (Other academic)
  • 265. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Supporting interaction in the robocare intelligent assistive environment2007In: Proceedings of AAAI spring symposium on interaction challenges for intelligent assistants, 2007Conference paper (Refereed)
  • 266. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Synthesizing proactive assistance with heterogeneous agents2007In: AI*IA 2007: Artificial Intelligence and Human-Oriented Computing: Proceedings of the 10th Congress of the Italian Association for Artificial Intelligence, Rome, Italy, September 10-13, 2007, Springer Berlin/Heidelberg, 2007, Vol. 4733, no 1, p. 495-506Conference paper (Refereed)
  • 267. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Rasconi, Riccardo
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Scopelliti, Massimiliano
    Tiberio, Lorenza
    Monitoring elderly people with the robocare domestic environment: interaction synthesis and user evaluation2011In: Computational intelligence, ISSN 0824-7935, E-ISSN 1467-8640, Vol. 27, no 1, p. 60-82Article in journal (Refereed)
    Abstract [en]

    This article describes aspects of a fully implemented artificial intelligence (AI) system that integrates multiple intelligent components to actively assist an elderly person at home. Specifically, we describe how constraint-based scheduling technology is used to actively monitor a pattern of activities executed by the person and how detected temporal constraint violations are used to trigger meaningful and contextualized proactive interactions. This article also presents a psychological evaluation of the system focusing on elderly people’s attitudes, in which system acceptability, perceived utility, interaction modality, and emotional response are considered.

  • 268. Cesta, Amedeo
    et al.
    Farinelli, Alessandro
    Iocchi, Luca
    Leone, Riccardo G.
    Nardi, Daniele
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    “Robotically Rich” environments for supporting elderly people at home: the RoboCare experience2005In: Proceedings of Symposium on Robot Companions: Hard Problems and Open Challenges in Robot-Human Interaction, 2005Conference paper (Refereed)
  • 269. Cesta, Amedeo
    et al.
    Fratini, Simone
    Oddi, Angelo
    Pecora, Federico
    Örebro University, School of Science and Technology.
    APSI Case# 1: pre-planning science operations in Mars Express2008In: Proceedings of International Symposium on Artificial Intelligence, Robotics and Automation for Space (ISAIRAS'08), 2008Conference paper (Refereed)
  • 270. Cesta, Amedeo
    et al.
    Fratini, Simone
    Pecora, Federico
    Örebro University, Department of Technology.
    A multi-component framework for planning and scheduling integration2007In: Proceedings of UK Planning and Scheduling SIG (PlanSig'07), 2007Conference paper (Refereed)
  • 271. Cesta, Amedeo
    et al.
    Fratini, Simone
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Planning with multiple-components in OMPS2008In: New frontiers in applied artificial intelligence / [ed] Ngoc Thanh Nguyen, Leszek Borzemski, Adam Grzech, Moonis Ali, Springer Berlin/Heidelberg, 2008, p. 435-445Conference paper (Refereed)
  • 272. Cesta, Amedeo
    et al.
    Fratini, Simone
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Unifying planning and scheduling as timelines in a component-based perspective2008In: Archives of Control Science, ISSN 1230-2384, Vol. 18, no 2, p. 231-271Article in journal (Refereed)
    Abstract [en]

    The timeline-based approach to planning represents an effective alternative to classical planning for complex domains requiring the use of both temporal reasoning and scheduling features. This paper discusses the constraint-based approach to timeline planning and scheduling introduced in OMPS.  OMPS is a an architecture for problem solving which draws inspiration from both control theory and constraint-based reasoning, and which is based on the notion of components.The rationale behind the component-based approach shares with classical control theory a basic modeling perspective: the planning and scheduling problem is represented by identifying a set of relevant domain components which need to be controlled to obtain a desired temporal behavior for the entire system. Components are entities whose properties may vary in time and which model one or more physical (or logical) domain subsystems relevant to a given planning context. The planner/scheduler plays the role of the controller for these entities, and reasons in terms of constraints that bound their internal evolutions and the desired properties of the generated behaviors (goals). Our work complements this modeling assumption with a constraint-based computational framework.  Admissible temporal behaviors of components are specified as a set of causal constraints within a rich temporal specification, and goals are specified as temporal constraint preferences.  The OMPS software architecture presented in this paper combines both specific and generic constraint solvers in defining consistent timelines which satisfy a given set of goals.

    Download full text (pdf)
    Fulltext
  • 273. Cesta, Amedeo
    et al.
    Iocchi, Luca
    Leone, Giuseppe R.
    Nardi, Daniele
    Pecora, Federico
    Örebro University, Department of Technology.
    Robotic, sensory and problem-solving ingredients for the future home2009In: Intelligent environments: methods, algorithms and applications / [ed] Dorothy Monekosso, Yoshinori Kuno, Springer Berlin/Heidelberg, 2009, p. 67-87Chapter in book (Refereed)
  • 274. Cesta, Amedeo
    et al.
    Pecora, Federico
    Örebro University, Department of Technology.
    The robocare project: intelligent systems for elder care2005In: Proceedings of AAAI fall symposium on caring machines, AI in elder care, 2005Conference paper (Refereed)
  • 275. Cesta, Amedeo
    et al.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    The robocare project: multi-agent systems for the care of the elderly2003In: ERCIM News, ISSN 0926-4981, E-ISSN 1564-0094, no 53Article in journal (Other academic)
  • 276. Cesta, Amedeo
    et al.
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    A component-based framework for loosely-coupled planning and scheduling integrations2003In: Proceedings of the First RoboCare Workshop / [ed] Amedeo Cesta, Roma, Italy: ISTC-CNR , 2003, p. 33-38Conference paper (Other academic)
  • 277. Cesta, Amedeo
    et al.
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Biasing the structure of scheduling problems through classical planners2004In: Proceedings of Workshop on Integrating Planning into Scheduling (WIPIS) at ICAPS'04, 2004Conference paper (Refereed)
  • 278.
    Chadalavada, Ravi Teja
    Chalmers University of Technology.
    Human Robot Interaction for Autonomous Systems in Industrial Environments2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The upcoming new generation of autonomous vehicles for transporting materials in industrial environments will be more versatile, flexible and efficient than traditional Automatic Guided Vehicles (AGV), which simply follow pre-defined paths. However, freely navigating vehicles can appear unpredictable to human workers and thus cause stress and render joint use of the available space inefficient. This work addresses the problem of providing information regarding a service robot’s intention to humans co-populating the environment. The overall goal is to make humans feel safer and more comfortable, even when they are in close vicinity of the robot. A spatial Augmented Reality (AR) system for robot intention communication by means of projecting proxemic information onto shared floor space is developed on a robotic fork-lift by equipping it with a LED projector. This helps in visualizing internal state information and intents on the shared floors spaces. The robot’s ability to communicate its intentions is evaluated in realistic situations where test subjects meet the robotic forklift. A Likert scalebased evaluation which also includes comparisons to human-human intention communication was performed. The results show that already adding simple information, such as the trajectory and the space to be occupied by the robot in the near future, is able to effectively improve human response to the robot. This kind of synergistic human-robot interaction in a work environment is expected to increase the robot’s acceptability in the industry.

    Download full text (pdf)
    fulltext
  • 279.
    Chadalavada, Ravi Teja
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Empirical evaluation of human trust in an expressive mobile robot2016In: Proceedings of RSS Workshop "Social Trust in Autonomous Robots 2016", 2016Conference paper (Refereed)
    Abstract [en]

    A mobile robot communicating its intentions using Spatial Augmented Reality (SAR) on the shared floor space makes humans feel safer and more comfortable around the robot. Our previous work [1] and several other works established this fact. We built upon that work by adding an adaptable information and control to the SAR module. An empirical study about how a mobile robot builds trust in humans by communicating its intentions was conducted. A novel way of evaluating that trust is presented and experimentally shown that adaption in SAR module lead to natural interaction and the new evaluation system helped us discover that the comfort levels between human-robot interactions approached those of human-human interactions.

    Download full text (pdf)
    fulltext
  • 280.
    Chadalavada, Ravi Teja
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    That’s on my Mind!: Robot to Human Intention Communication through on-board Projection on Shared Floor Space2015In: 2015 European Conference on Mobile Robots (ECMR), New York: IEEE conference proceedings , 2015Conference paper (Refereed)
    Abstract [en]

    The upcoming new generation of autonomous vehicles for transporting materials in industrial environments will be more versatile, flexible and efficient than traditional AGVs, which simply follow pre-defined paths. However, freely navigating vehicles can appear unpredictable to human workers and thus cause stress and render joint use of the available space inefficient. Here we address this issue and propose on-board intention projection on the shared floor space for communication from robot to human. We present a research prototype of a robotic fork-lift equipped with a LED projector to visualize internal state information and intents. We describe the projector system and discuss calibration issues. The robot’s ability to communicate its intentions is evaluated in realistic situations where test subjects meet the robotic forklift. The results show that already adding simple information, such as the trajectory and the space to be occupied by the robot in the near future, is able to effectively improve human response to the robot.

  • 281.
    Chadalavada, Ravi Teja
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Schindler, Maike
    Faculty of Human Sciences, University of Cologne, Germany, Cologne, Gemany.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Implicit intention transference using eye-tracking glasses for improved safety in human-robot interaction2019Conference paper (Refereed)
    Abstract [en]

    Eye gaze can convey information about intentions beyond what can beinferred from the trajectory and head pose of a person. We propose eye-trackingglasses as safety equipment in industrial environments shared by humans androbots. In this work, an implicit intention transference system was developed and implemented. Robot was given access to human eye gaze data, and it responds tothe eye gaze data through spatial augmented reality projections on the sharedfloor space in real-time and the robot could also adapt its path. This allows proactivesafety approaches in HRI for example by attempting to get the human'sattention when they are in the vicinity of a moving robot. A study was conductedwith workers at an industrial warehouse. The time taken to understand the behaviorof the system was recorded. Electrodermal activity and pupil diameter wererecorded to measure the increase in stress and cognitive load while interactingwith an autonomous system, using these measurements as a proxy to quantifytrust in autonomous systems.

    Download full text (pdf)
    Implicit intention transference using eye-tracking glasses for improved safety in human-robot interaction
  • 282.
    Chadalavada, Ravi Teja
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Schindler, Maike
    Örebro University, School of Science and Technology.
    Palm, Rainer
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Accessing your navigation plans! Human-Robot Intention Transfer using Eye-Tracking Glasses2018In: Advances in Manufacturing Technology XXXII: Proceedings of the 16th International Conference on Manufacturing Research, incorporating the 33rd National Conference on Manufacturing Research, September 11–13, 2018, University of Skövde, Sweden / [ed] Case K. &Thorvald P., Amsterdam, Netherlands: IOS Press, 2018, p. 253-258Conference paper (Refereed)
    Abstract [en]

    Robots in human co-habited environments need human-aware task and motion planning, ideally responding to people’s motion intentions as soon as they can be inferred from human cues. Eye gaze can convey information about intentions beyond trajectory and head pose of a person. Hence, we propose eye-tracking glasses as safety equipment in industrial environments shared by humans and robots. This paper investigates the possibility of human-to-robot implicit intention transference solely from eye gaze data.  We present experiments in which humans wearing eye-tracking glasses encountered a small forklift truck under various conditions. We evaluate how the observed eye gaze patterns of the participants related to their navigation decisions. Our analysis shows that people primarily gazed on that side of the robot they ultimately decided to pass by. We discuss implications of these results and relate to a control approach that uses human eye gaze for early obstacle avoidance.

    Download full text (pdf)
    Accessing your navigation plans! Human-Robot Intention Transfer using Eye-Tracking Glasses
  • 283.
    Chang, Chujie
    et al.
    Kyushu University, Fukuoka, Japan.
    Miyauchi, Shoko
    Kyushu University, Fukuoka, Japan.
    Morooka, Ken'ichi
    Okayama University, Okayama, Japan.
    Kurazume, Ryo
    Kyushu University, Fukuoka, Japan.
    Martinez Mozos, Oscar
    Örebro University, School of Science and Technology.
    FusionNet: A Frame Interpolation Network for 4D Heart Models2023In: Medical Image Computing and Computer Assisted Intervention – MICCAI 2023 Workshops: MTSAIL 2023, LEAF 2023, AI4Treat 2023, MMMI 2023, REMIA 2023, Held in Conjunction with MICCAI 2023, Vancouver, BC, Canada, October 8–12, 2023, Proceedings / [ed] Jonghye Woo, Alessa Hering, Wilson Silva, ..., Springer, 2023, Vol. 14394, p. 35-44Conference paper (Refereed)
    Abstract [en]

    Cardiac magnetic resonance (CMR) imaging is widely used to visualise cardiac motion and diagnose heart disease. However, standard CMR imaging requires patients to lie still in a confined space inside a loud machine for 40-60 min, which increases patient discomfort. In addition, shorter scan times decrease either or both the temporal and spatial resolutions of cardiac motion, and thus, the diagnostic accuracy of the procedure. Of these, we focus on reduced temporal resolution and propose a neural network called FusionNet to obtain four-dimensional (4D) cardiac motion with high temporal resolution from CMR images captured in a short period of time. The model estimates intermediate 3D heart shapes based on adjacent shapes. The results of an experimental evaluation of the proposed FusionNet model showed that it achieved a performance of over 0.897 in terms of the Dice coefficient, confirming that it can recover shapes more precisely than existing methods. This code is available at: https://github.com/smiyauchi199/FusionNet.git.

  • 284.
    Charusta, Krzysztof
    et al.
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Iliev, Boyko
    Örebro University, School of Science and Technology.
    Extraction of grasp-related features by human dual-hand object exploration2009In: 2009 International Conference on Advanced Robotics, Piscataway, NJ: IEEE conference proceedings, 2009, p. 1-6Conference paper (Refereed)
    Abstract [en]

    We consider the problem of objects exploration for grasping purposes, specifically in cases where vision based methods are not applicable. A novel dual-hand object exploration method is proposed that takes benefits from a human demonstration to enrich knowledge about an object. The user handles an object freely using both hands, without restricting the object pose. A set of grasp-related features obtained during exploration is demonstrated and utilized to generate grasp oriented bounding boxes that are basis for pre-grasp hypothesis. We believe that such exploration done in a natural and user friendly way creates important link between an operator intention and a robot action.

  • 285.
    Charusta, Krzysztof
    et al.
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar
    Örebro University, School of Science and Technology.
    Iliev, Boyko
    Örebro University, School of Science and Technology.
    Independent contact regions based on a patch contact model2012In: 2012 IEEE International Conference on Robotics and Automation (ICRA), IEEE conference proceedings, 2012, p. 4162-4169Conference paper (Refereed)
    Abstract [en]

    The synthesis of multi-fingered grasps on nontrivial objects requires a realistic representation of the contact between the fingers of a robotic hand and an object. In this work, we use a patch contact model to approximate the contact between a rigid object and a deformable anthropomorphic finger. This contact model is utilized in the computation of Independent Contact Regions (ICRs) that have been proposed as a way to compensate for shortcomings in the finger positioning accuracy of robotic grasping devices. We extend the ICR algorithm to account for the patch contact model and show the benefits of this solution.

  • 286.
    Charusta, Krzysztof
    et al.
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar
    Örebro University, School of Science and Technology.
    Iliev, Boyko
    Örebro University, School of Science and Technology.
    Generation of independent contact regions on objects reconstructed from noisy real-world range data2012In: 2012 IEEE International Conference on Robotics and Automation (ICRA), IEEE conference proceedings, 2012, p. 1338-1344Conference paper (Refereed)
    Abstract [en]

    The synthesis and evaluation of multi-fingered grasps on complex objects is a challenging problem that has received much attention in the robotics community. Although several promising approaches have been developed, applications to real-world systems are limited to simple objects or gripper configurations. The paradigm of Independent Contact Regions (ICRs) has been proposed as a way to increase the tolerance to grasp positioning errors. This concept is well established, though only on precise geometric object models. This work is concerned with the application of the ICR paradigm to models reconstructed from real-world range data. We propose a method for increasing the robustness of grasp synthesis on uncertain geometric models. The sensitivity of the ICR algorithm to noisy data is evaluated and a filtering approach is proposed to improve the quality of the final result.

  • 287.
    Chatzipetrou, Panagiota
    et al.
    Department of Informatics, Aristotle University of Thessaloniki, Greece.
    Angelis, Lefteris
    Department of Informatics, Aristotle University of Thessaloniki, Greece.
    Barney, Sebastian
    Blekinge Institute of Technology, Karlskrona, Sweden.
    Wohlin, Claes
    Blekinge Institute of Technology, Karlskrona, Sweden.
    Software product quality in global software development: Finding groups with aligned goals2011In: 37th EUROMICRO Conference on Software Engineering and Advanced Applications (SEAA 2011) / [ed] Biffl, S; Koivuluoma, M; Abrahamsson, P; Oivo, M, IEEE Computer Society, 2011, p. 435-442Conference paper (Refereed)
    Abstract [en]

    The development of a software product in an organization involves various groups of stakeholders who may prioritize the qualities of the product differently. This paper presents an empirical study of 65 individuals in different roles and in different locations, including on shoring, outsourcing and off shoring, prioritizing 24 software quality aspects. Hierarchical cluster analysis is applied to the prioritization data, separately for the situation today and the ideal situation, and the composition of the clusters, regarding the distribution of the inherent groupings within each of them, is analyzed. The analysis results in observing that the roles are not that important in the clustering. However, compositions of clusters regarding the onshore-offshore relationships are significantly different, showing that the offshore participants have stronger tendency to cluster together. In conclusion, stakeholders seem to form clusters of aligned understanding of priorities according to personal and cultural views rather than their roles in software development.

  • 288.
    Chatzipetrou, Panagiota
    et al.
    Department of Informatics, Aristotle University of Thessaloniki, Greece.
    Karapiperis, Christos
    Department of Informatics, Aristotle University of Thessaloniki, Greece.
    Palampouiki, Chrysa
    Department of Informatics, Aristotle University of Thessaloniki, Greece.
    Angelis, Lefteris
    Department of Informatics, Aristotle University of Thessaloniki, Greece.
    Statistical Analysis of Requirements Prioritization for Transition to Web Technologies: A Case Study in an Electric Power Organization2014In: Software Quality. Model-Based Approaches for Advanced Software and Systems Engineering: 6th International Conference, SWQD 2014, Vienna, Austria, January 14-16, 2014. Proceedings / [ed] Winkler, D.; Biffl, S.; Bergsmann, J., Cham: Springer, 2014, p. 63-84Conference paper (Refereed)
    Abstract [en]

    Transition from an existing IT system to modern Web technologies provides multiple benefits to an organization and its customers. Such a transition in a large organization involves various groups of stakeholders who may prioritize differently the requirements of the software under development. In our case study, the organization is a leading domestic company in the field of electricity power. The existing online system supports the customer service along with the technical activities and has more than 1,500 registered users, while simultaneous access can be reached by 300 users. The paper presents an empirical study where 51 employees in different roles prioritize 18 software requirements using hierarchical cumulative voting. The goal of this study is to test significant differences in prioritization between groups of stakeholders. Statistical methods involving data transformation, ANOVA and Discriminant Analysis were applied to data. The results showed significant differences between roles of the stakeholders in certain requirements.

  • 289.
    Chella, Antonio
    et al.
    Università di Palermo.
    Coradeschi, Silvia
    Örebro University, Department of Technology.
    Frixione, Marcello
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Perceptual anchoring via conceptual spaces2004Conference paper (Refereed)
    Abstract [en]

    Perceptual anchoring is the problem of creating and maintaining in time the connection between symbols and sensor data that refer to the same physical objects. This is one of the facets of the general problem of integrating symbolic and non-symbolic processes in an intelligent system. Gärdenfors' conceptual spaces provide a geometric treatment of knowledge which bridges the gap between the symbolic and sub-symbolic approaches. As such, they can be used for the study of the anchoring problem. In this paper, we propose a computational framework for anchoring based on conceptual spaces. Our framework exploits the geometric structure of conceptual spaces for many of the crucial tasks of anchoring, like matching percepts to symbolic descriptions or tracking the evolution of objects over time.

  • 290.
    Chen, Zetao
    et al.
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Lowry, Stephanie
    Örebro University, School of Science and Technology.
    Jacobson, Adam
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Ge, ZongYuan
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Milford, Michael
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Distance metric learning for feature-agnostic place recognition2015In: Proceedings of the 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, 2015, p. 2556-2563Conference paper (Refereed)
    Abstract [en]

    The recent focus on performing visual navigation and place recognition in changing environments has resulted in a large number of heterogeneous techniques each utilizing their own learnt or hand crafted visual features. This paper presents a generally applicable method for learning the appropriate distance metric by which to compare feature responses from any of these techniques in order to perform place recognition under changing environmental conditions. We implement an approach which learns to cluster images captured at spatially proximal locations under different conditions, separated from frames captured at different places. The formulation is a convex optimization, guaranteeing the existence of a global solution. We evaluate the general applicability of our method on two benchmark change datasets using three typical image pre-processing and feature types: GIST, Principal Component Analysis and learnt Convolutional Neural Network features. The results demonstrate that the distance metric learning approach uniformly improves single-image-based visual place recognition performance across all feature types. Furthermore, we demonstrate that this performance improvement is maintained when the sequence-based algorithm SeqSLAM is applied to the single-image place recognition results, leading to state-of-the-art performance.

  • 291.
    Chen, Zetao
    et al.
    School of Electrical Engineering and Computer Science, Queensland University of Technology, Brisbane Qld, Australia; Australian Centre for Robotic Vision, Queensland University of Technology, Brisbane Qld, Australia.
    Lowry, Stephanie
    School of Electrical Engineering and Computer Science, Queensland University of Technology, Brisbane Qld, Australia.
    Jacobson, Adam
    School of Electrical Engineering and Computer Science, Queensland University of Technology, Brisbane Qld, Australia; Australian Centre for Robotic Vision, Queensland University of Technology, Brisbane Qld, Australia.
    Hasselmo, Michael E.
    Center for Memory and Brain and Graduate Program for Neuroscience, Boston University, Boston, United States.
    Milford, Michael
    School of Electrical Engineering and Computer Science, Queensland University of Technology, Brisbane Qld, Australia; Australian Centre for Robotic Vision, Queensland University of Technology, Brisbane Qld, Australia.
    Bio-inspired homogeneous multi-scale place recognition2015In: Neural Networks, ISSN 0893-6080, E-ISSN 1879-2782, Vol. 72, p. 48-61Article in journal (Refereed)
    Abstract [en]

    Robotic mapping and localization systems typically operate at either one fixed spatial scale, or over two, combining a local metric map and a global topological map. In contrast, recent high profile discoveries in neuroscience have indicated that animals such as rodents navigate the world using multiple parallel maps, with each map encoding the world at a specific spatial scale. While a number of theoretical-only investigations have hypothesized several possible benefits of such a multi-scale mapping system, no one has comprehensively investigated the potential mapping and place recognition performance benefits for navigating robots in large real world environments, especially using more than two homogeneous map scales. In this paper we present a biologically-inspired multi-scale mapping system mimicking the rodent multi-scale map. Unlike hybrid metric-topological multi-scale robot mapping systems, this new system is homogeneous, distinguishable only by scale, like rodent neural maps. We present methods for training each network to learn and recognize places at a specific spatial scale, and techniques for combining the output from each of these parallel networks. This approach differs from traditional probabilistic robotic methods, where place recognition spatial specificity is passively driven by models of sensor uncertainty. Instead we intentionally create parallel learning systems that learn associations between sensory input and the environment at different spatial scales. We also conduct a systematic series of experiments and parameter studies that determine the effect on performance of using different neural map scaling ratios and different numbers of discrete map scales. The results demonstrate that a multi-scale approach universally improves place recognition performance and is capable of producing better than state of the art performance compared to existing robotic navigation algorithms. We analyze the results and discuss the implications with respect to several recent discoveries and theories regarding how multi-scale neural maps are learnt and used in the mammalian brain.

  • 292.
    Cheng, Lu
    et al.
    School of Electrical and Information Engineering, Tianjin University, Tianjin, People's Republic of China .
    Meng, Qing-Hao
    School of Electrical and Information Engineering, Tianjin University, Tianjin, People's Republic of China .
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Qi, Pei-Feng
    National Computer Network Emergency Response Technical Team/Coordination Center of China (CNCERT/CC), Beijing, People's Republic of China .
    Development of compact electronic noses: a review2021In: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 32, no 6, article id 062002Article, review/survey (Refereed)
    Abstract [en]

    An electronic nose (e-nose) is a measuring instrument that mimics human olfaction and outputs 'fingerprint' information of mixed gases or odors. Generally speaking, an e-nose is mainly composed of two parts: a gas sensing system (gas sensor arrays, gas transmission paths) and an information processing system (microprocessor and related hardware, pattern recognition algorithms). It has been more than 30 years since the e-nose concept was introduced in the 1980s. Since then, e-noses have evolved from being large in size, expensive, and power-hungry instruments to portable, low cost devices with low power consumption. This paper reviews the development of compact e-nose design and calculation over the last few decades, and discusses possible future trends. Regarding the compact e-nose design, which is related to its size and weight, this paper mainly summarizes the development of sensor array design, hardware circuit design, gas path (i.e. the path through which the mixed gases to be measured flow inside the e-nose system) and sampling design, as well as portable design. For the compact e-nose calculation, which is directly related to its rapidity of detection, this review focuses on the development of on-chip calculation and wireless computing. The future trends of compact e-noses include the integration with the internet of things, wearable e-noses, and mobile e-nose systems.

  • 293.
    Chimamiwa, Gibson
    et al.
    Örebro University, School of Science and Technology.
    Alirezaie, Marjan
    Örebro University, School of Science and Technology.
    Banaee, Hadi
    Örebro University, School of Science and Technology.
    Köckemann, Uwe
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Towards Habit Recognition in Smart Homes for People with Dementia2019In: Ambient Intelligence: 15th European Conference, AmI 2019, Rome, Italy, November 13–15, 2019, Proceedings / [ed] Ioannis Chatzigiannakis, Boris De Ruyter, Irene Mavrommati, Springer Nature, 2019, Vol. 11912, p. 363-369Conference paper (Refereed)
    Abstract [en]

    The demand for smart home technologies that enable ageingin place is rising. Through activity recognition, users’ activities can be monitored. However, for dementia patients, activity recognition alone cannot address the challenges associated with changes in the user’s habits along the disease’s stage transitions. Extending activity recognition to habit recognition enables the capturing of patients’ habits and change sin habits in order to detect anomalies. This paper aims to introduce relevant features for habit recognition solutions, extracted from data, in order to enrich the representation of the user’s habits. This solution is personalisable to meet the specific needs of the patients and generalizable for use in different scenarios. In this way caregivers are better informed on the expected changes of the patient’s habits, which can help to mitigate further deterioration through early treatment and intervention.

  • 294.
    Chimamiwa, Gibson
    et al.
    Örebro University, School of Science and Technology.
    Alirezaie, Marjan
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Multi-sensor dataset of human activities in a smart home environment2021In: Data in Brief, E-ISSN 2352-3409, Vol. 34, article id 106632Article in journal (Refereed)
    Abstract [en]

    Time series data acquired from sensors deployed in smart homes present valuable information for intelligent systems to learn activity patterns of occupants. With the increasing need to enable people to age in place independently, the availability of such data is key to the development of home monitoring solutions. In this article we describe an unlabelled dataset of measurements collected from multiple environmental sensors placed in a smart home to capture human activities of daily living. Various sensors were used including passive infrared, force sensing resistors, reed switches, mini photocell light sensors, temperature and humidity, and smart plugs. The sensors record data from the user's interactions with the environment, such as indoor movements, pressure applied on the bed, or current consumption when using electrical appliances. Millions of raw sensor data samples were collected continuously at a frequency of 1 Hz over a period of six months between 26 February 2020 and 26 August 2020. The dataset can be useful in the analysis of different methods, including data-driven algorithms for activity or habit recognition. In particular, the research community might be interested in investigating the performance of algorithms when applied on unlabelled datasets and not necessarily on annotated datasets. Furthermore, by applying artificial intelligence (AI) algorithms on such data collected over long periods, it is possible to extract patterns that reveal the user's habits as well as detect changes in the habits. This can benefit in detecting deviations in order to provide timely interventions for patients, e.g., people with dementia.

  • 295.
    Cielniak, Grzegorz
    Örebro University, Department of Technology.
    People tracking by mobile robots using thermal and colour vision2007Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis addresses the problem of people detection and tracking by mobile robots in indoor environments. A system that can detect and recognise people is an essential part of any mobile robot that is designed to operate in populated environments. Information about the presence and location of persons in the robot’s surroundings is necessary to enable interaction with the human operator, and also for ensuring the safety of people near the robot.

    The presented people tracking system uses a combination of thermal and colour information to robustly track persons. The use of a thermal camera simplifies the detection problem, which is especially difficult on a mobile platform. The system is based on a fast and efficient samplebased tracking method that enables tracking of people in real-time. The elliptic measurement model is fast to calculate and allows detection and tracking of persons under different views. An explicit model of the human silhouette effectively distinguishes persons from other objects in the scene. Moreover the process of detection and localisation is performed simultaneously so that measurements are incorporated directly into the tracking framework without thresholding of observations. With this approach persons can be detected independently from current light conditions and in situations where other popular detection methods based on skin colour would fail.

    A very challenging situation for a tracking system occurs when multiple persons are present on the scene. The tracking system has to estimate the number and position of all persons in the vicinity of the robot. Tracking of multiple persons in the presented system is realised by an efficient algorithm that mitigates the problems of combinatorial explosion common to other known algorithms. A sequential detector initialises an independent tracking filter for each new person appearing in the image. A single filter is automatically deleted when it stops tracking a person. While thermal vision is good for detecting people, it can be very difficult to maintain the correct association between different observations and persons, especially where they occlude one another, due to the unpredictable appearance and social behaviour of humans. To address these problems the presented tracking system uses additional information from the colour camera. An adaptive colour model is incorporated into the measurement model of the tracker to improve data association. For this purpose an efficient integral image based method is used to maintain the real-time performance of the tracker. To deal with occlusions the system uses an explicit method that first detects situations where people occlude each other. This is realised by a new approach based on a machine learning classifier for pairwise comparison of persons that uses both thermal and colour features provided by the tracker. This information is then incorporated into the tracker for occlusion handling and to resolve situations where persons reappear in a scene.

    Finally the thesis presents a comprehensive, quantitative evaluation of the whole system and its different components using a set of well defined performance measures. The behaviour of the system was investigated on different data sets including different real office environments and different appearances and behaviours of persons. Moreover the influence of all important system parameters on the performance of the system was checked and their values optimised based on these results.

    Download full text (pdf)
    FULLTEXT01
  • 296.
    Cielniak, Grzegorz
    et al.
    Örebro University, Department of Technology.
    Duckett, Tom
    Örebro University, Department of Technology.
    People recognition by mobile robots2004In: Journal of Intelligent & Fuzzy Systems, ISSN 1064-1246, E-ISSN 1875-8967, Vol. 15, no 1, p. 21-27Article in journal (Refereed)
    Abstract [en]

    This paper addresses the problem of detecting and identifying persons with a mobile robot, by sensory fusion of thermal and colour vision information. In the proposed system, people are first detected with a thermal camera, using image analysis techniques to segment the persons in the thermal images. This information is then used to segment the corresponding regions of the colour images, using an affine transformation to solve the image correspondence between the two cameras. After segmentation, the region of the image containing a person is further divided into regions corresponding to the person's head, torso and legs. Temperature and colour features are then extracted from each region for input to a pattern recognition system. Three alternative classfication methods were investigated in experiments with a moving mobile robot and moving persons in an office environment. The best identification performance was obtained with a dynamic recognition method based on a Bayes classifier, which takes into account evidence accumulated in a sequence of images.

  • 297.
    Cielniak, Grzegorz
    et al.
    Sch Comp Sci, Lincoln Univ, Lincoln, England.
    Duckett, Tom
    Sch Comp Sci, Lincoln Univ, Lincoln, England.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Data association and occlusion handling for vision-based people tracking by mobile robots2010In: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 58, no 5, p. 435-443Article in journal (Refereed)
    Abstract [en]

    This paper presents an approach for tracking multiple persons on a mobile robot with a combination of colour and thermal vision sensors, using several new techniques. First, an adaptive colour model is incorporated into the measurement model of the tracker. Second, a new approach for detecting occlusions is introduced, using a machine learning classifier for pairwise comparison of persons (classifying which one is in front of the other). Third, explicit occlusion handling is incorporated into the tracker. The paper presents a comprehensive, quantitative evaluation of the whole system and its different components using several real world data sets. (C) 2010 Elsevier B.V. All rights reserved.

  • 298.
    Cielniak, Grzegorz
    et al.
    Örebro University, Department of Technology.
    Miladinovic, Mihajlo
    Dept. of Technology, AASS, Örebro University, Örebro, Sweden.
    Hammarin, Daniel
    Dept. of Technology, AASS, Örebro University, Örebro, Sweden.
    Göransson, Linus
    Dept. of Technology, AASS, Örebro University, Örebro, Sweden.
    Lilienthal, Achim J.
    Örebro University, Department of Technology.
    Duckett, Tom
    Örebro University, Department of Technology.
    Appearance-based tracking of persons with an omnidirectional vision sensor2003In: IEEE Computer Society Conference on Computer Vision and Pattern Recognition Workshops, IEEE, 2003, Vol. 7, article id 4624346Conference paper (Refereed)
    Abstract [en]

    This paper addresses the problem of tracking a moving person with a single, omnidirectional camera. An appearance-based tracking system is described which uses a self-acquired appearance model and a Kalman filter to estimate the position of the person. Features corresponding to ``depth cues'' are first extracted from the panoramic images, then an artificial neural network is trained to estimate the distance of the person from the camera. The estimates are combined using a discrete Kalman filter to track the position of the person over time. The ground truth information required for training the neural network and the experimental analysis was obtained from another vision system, which uses multiple webcams and triangulation to calculate the true position of the person. Experimental results show that the tracking system is accurate and reliable, and that its performance can be further improved by learning multiple, person-specific appearance models

    Download full text (pdf)
    Appearance-based Tracking of Persons with an Omnidirectional Vision Sensor
  • 299.
    Cielniak, Grzegorz
    et al.
    Örebro University, Department of Technology.
    Treptow, André
    University of Tübingen.
    Duckett, Tom
    Örebro University, Department of Technology.
    Quantitative performance evaluation of a people tracking system on a mobile robot2005Conference paper (Refereed)
    Abstract [en]

    Future service robots will need to keep track of the persons in their environment. A number of people tracking systems have been developed for mobile robots, but it is currently impossible to make objective comparisons of their performance. This paper presents a comprehensive, quantitative evaluation of a state-of-the-art people tracking system for a mobile robot in an office environment, for both single and multiple persons.

  • 300.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Planning in Inhabited Environments: Human-Aware Task Planning and Activity Recognition2010Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Promised some decades ago by researchers in artificial intelligence and robotics as an imminent breakthrough in our everyday lives, a robotic assistant that could work with us in our home and our workplace is a dream still far from being fulfilled. The work presented in this thesis aims at bringing this future vision a little closer to realization. Here, we start from the assumption that an efficient robotic helper should not impose constraints on users' activities, but rather perform its tasks unobtrusively to fulfill its goals and to facilitate people in achieving their objectives.  Also, the helper should be able to consider the outcome of possible future actions by the human users, to assess how those would affect the environment with respect to the agent's objectives, and to predict when its support will be needed. In this thesis we address two highly interconnected problems that are essential for the cohabitation of people and service robots: robot task planning and human activity recognition. First, we present human-aware planning, that is, our approach to robot high-level symbolic reasoning for plan generation. Human-aware planning can be applied in situations where there is a controllable agent, the robot, whose actions we can plan, and one or more uncontrollable agents, the human users, whose future actions we can only try to predict. In our approach, therefore, the knowledge of the users' current and future activities is an important prerequisite. We define human-aware as a new type of planning problem, we formalize the extensions needed by a classical planner to solve such a problem, and we present the implementation of a planner that satisfies all identified requirements. In this thesis we explore also a second issue, which is a prerequisite to the first one: human activity monitoring in intelligent environments. We adopt a knowledge driven approach to activity recognition, whereby a constraint-based domain description is used to correlate sensor readings to human activities. We validate our solutions to both human-aware planning and activity recognition both theoretically and experimentally, describing a number of explanatory examples and test runs in a real environment.

    Download full text (pdf)
    FULLTEXT03
    Download (pdf)
    COVER01
    Download (pdf)
    SPIKBLAD01
3456789 251 - 300 of 1393
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf