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  • 51.
    Arain, Muhammad Asif
    et al.
    Örebro University, School of Science and Technology.
    Trincavelli, Marco
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Schaffernicht, Erik
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Global coverage measurement planning strategies for mobile robots equipped with a remote gas sensor2015In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 15, no 3, 6845-6871 p.Article in journal (Refereed)
    Abstract [en]

    The problem of gas detection is relevant to many real-world applications, such as leak detection in industrial settings and landfill monitoring. In this paper, we address the problem of gas detection in large areas with a mobile robotic platform equipped with a remote gas sensor. We propose an algorithm that leverages a novel method based on convex relaxation for quickly solving sensor placement problems, and for generating an efficient exploration plan for the robot. To demonstrate the applicability of our method to real-world environments, we performed a large number of experimental trials, both on randomly generated maps and on the map of a real environment. Our approach proves to be highly efficient in terms of computational requirements and to provide nearly-optimal solutions.

  • 52.
    Argyriou, Marios
    et al.
    DTU Compute, Technical University of Denmark, Lyngby, Denmark.
    Dragoni, Nicola
    Örebro University, School of Science and Technology. DTU Compute, Technical University of Denmark, Lyngby, Denmark.
    Spognardi, Angelo
    DTU Compute, Technical University of Denmark, Lyngby, Denmark; Dipartimento Informatica, Sapienza Università di Roma, Rome, Italy.
    Security Flows in OAuth 2.0 Framework: A Case Study2017In: Computer safety, reliability, and security: SAFECOMP 2017 Workshops, ASSURE, DECSoS, SASSUR, TELERISE, and TIPS, Trento, Italy, September 12, 2017, Proceedings / [ed] Tonetta S., Schoitsch E., Bitsch F., Springer, 2017Conference paper (Refereed)
    Abstract [en]

    The burst in smartphone use, handy design in laptops and tablets as well as other smart products, like cars with the ability to drive you around, manifests the exponential growth of network usage and the demand of accessing remote data on a large variety of services. However, users notoriously struggle to maintain distinct accounts for every single service that they use. The solution to this problem is the use of a Single Sign On (SSO) framework, with a unified single account to authenticate user’s identity throughout the different services. In April 2007, AOL introduced OpenAuth framework. After several revisions and despite its wide adoption, OpenAuth 2.0 has still several flaws that need to be fixed in several implementations. In this paper, we present a thorough review about both benefits of this single token authentication mechanism and its open flaws.

  • 53.
    Asadi, Sahar
    Örebro University, School of Science and Technology.
    Towards Dense Air Quality Monitoring: Time-Dependent Statistical Gas Distribution Modelling and Sensor Planning2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis addresses the problem of gas distribution modelling for gas monitoring and gas detection. The presented research is particularly focused on the methods that are suitable for uncontrolled environments. In such environments, gas source locations and the physical properties of the environment, such as humidity and temperature may be unknown or only sparse noisy local measurements are available. Example applications include air pollution monitoring, leakage detection, and search and rescue operations.

    This thesis addresses how to efficiently obtain and compute predictive models that accurately represent spatio-temporal gas distribution.

    Most statistical gas distribution modelling methods assume that gas dispersion can be modelled as a time-constant random process. While this assumption may hold in some situations, it is necessary to model variations over time in order to enable applications of gas distribution modelling for a wider range of realistic scenarios.

    This thesis proposes two time-dependent gas distribution modelling methods. In the first method, a temporal (sub-)sampling strategy is introduced. In the second method, a time-dependent gas distribution modelling approach is presented, which introduces a recency weight that relates measurement to prediction time. These contributions are presented and evaluated as an extension of a previously proposed method called Kernel DM+V using several simulation and real-world experiments. The results of comparing the proposed time-dependent gas distribution modelling approaches to the time-independent version Kernel DM+V indicate a consistent improvement in the prediction of unseen measurements, particularly in dynamic scenarios under the condition that there is a sufficient spatial coverage. Dynamic scenarios are often defined as environments where strong fluctuations and gas plume development are present.

    For mobile robot olfaction, we are interested in sampling strategies that provide accurate gas distribution models given a small number of samples in a limited time span. Correspondingly, this thesis addresses the problem of selecting the most informative locations to acquire the next samples.

    As a further contribution, this thesis proposes a novel adaptive sensor planning method. This method is based on a modified artificial potential field, which selects the next sampling location based on the currently predicted gas distribution and the spatial distribution of previously collected samples. In particular, three objectives are used that direct the sensor towards areas of (1) high predictive mean and (2) high predictive variance, while (3) maximising the coverage area. The relative weight of these objectives corresponds to a trade-off between exploration and exploitation in the sampling strategy. This thesis discusses the weights or importance factors and evaluates the performance of the proposed sampling strategy. The results of the simulation experiments indicate an improved quality of the gas distribution models when using the proposed sensor planning method compared to commonly used methods, such as random sampling and sampling along a predefined sweeping trajectory. In this thesis, we show that applying a locality constraint on the proposed sampling method decreases the travelling distance, which makes the proposed sensor planning approach suitable for real-world applications where limited resources and time are available. As a real-world use-case, we applied the proposed sensor planning approach on a micro-drone in outdoor experiments.

    Finally, this thesis discusses the potential of using gas distribution modelling and sensor planning in large-scale outdoor real-world applications. We integrated the proposed methods in a framework for decision-making in hazardous inncidents where gas leakage is involved and applied the gas distribution modelling in two real-world use-cases. Our investigation indicates that the proposed sensor planning and gas distribution modelling approaches can be used to inform experts both about the gas plume and the distribution of gas in order to improve the assessment of an incident.

  • 54.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Badica, Costin
    University of Craiova.
    Comes, Tina
    Karslruhe Institute of Technology.
    Conrado, Claudine
    Thales Research and Technology, Delft.
    Evers, Vanessa
    University of Amsterdam.
    Groen, Frans
    University of Amsterdam.
    Illie, Sorin
    University of Craiova.
    Steen Jensen, Jan
    DEMA, Denmark.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Milan, Bianca
    DCMR, Delft.
    Neidhart, Thomas
    Space Applications Services, Zaventem, Belgium,.
    Nieuwenhuis, Kees
    Thales Research and Technology, Delft.
    Pashami, Sepideh
    Örebro University, School of Science and Technology.
    Pavlin, Gregor
    Thales Research and Technology, Delft.
    Pehrsson, Jan
    Prolog Development Center, Denmark.
    Pinchuk, Rani
    Space Applications and Services.
    Scafes, Mihnea
    University of Craiova.
    Schou-Jensen, Leo
    DCMR, Denmark.
    Schultmann, Frank
    Karslruhe Institute of Technology.
    Wijngaards, Niek
    Thales Research and Technology, Delft, the Netherlands.
    ICT solutions supporting collaborative information acquisition, situation assessment and decision making in contemporary environmental management problems: the DIADEM approach2011In: Proceedings of the 25th EnviroInfo Conference "Environmental Informatics", 2011, 920-931 p.Conference paper (Refereed)
    Abstract [en]

    This paper presents a framework of ICT solutions developed in the EU research project DIADEM that supports environmental management with an enhanced capacity to assess population exposure and health risks, to alert relevant groups and to organize efficient response. The emphasis is on advanced solutions which are economically feasible and maximally exploit the existing communication, computing and sensing resources. This approach enables efficient situation assessment in complex environmental management problems by exploiting relevant information obtained from citizens via the standard communication infrastructure as well as heterogeneous data acquired through dedicated sensing systems. This is achieved through a combination of (i) advanced approaches to gas detection and gas distribution modelling, (ii) a novel service-oriented approach supporting seamless integration of human-based and automated reasoning processes in large-scale collaborative sense making processes and (iii) solutions combining Multi-Criteria Decision Analysis, Scenario-Based Reasoning and advanced human-machine interfaces. This paper presents the basic principles of the DIADEM solutions, explains how different techniques are combined to a coherent decision support system and briefly discusses evaluation principles and activities in the DIADEM project.

  • 55.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Approaches to Time-Dependent Gas Distribution Modelling2015In: 2015 European Conference on Mobile Robots (ECMR), New York: IEEE conference proceedings , 2015, 7324215Conference paper (Refereed)
    Abstract [en]

    Mobile robot olfaction solutions for gas distribution modelling offer a number of advantages, among them autonomous monitoring in different environments, mobility to select sampling locations, and ability to cooperate with other systems. However, most data-driven, statistical gas distribution modelling approaches assume that the gas distribution is generated by a time-invariant random process. Such time-invariant approaches cannot model well developing plumes or fundamental changes in the gas distribution. In this paper, we discuss approaches that explicitly consider the measurement time, either by sub-sampling according to a given time-scale or by introducing a recency weight that relates measurement and prediction time. We evaluate the performance of these time-dependent approaches in simulation and in real-world experiments using mobile robots. The results demonstrate that in dynamic scenarios improved gas distribution models can be obtained with time-dependent approaches.

  • 56.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Reggente, Matteo
    Örebro University, School of Science and Technology.
    Stachniss, Cyrill
    University of Freiburg.
    Plagemann, Christian
    Stanford University.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Statistical gas distribution modeling using kernel methods2011In: Intelligent systems for machine olfaction: tools and methodologies / [ed] E. L. Hines and M. S. Leeson, IGI Global, 2011, 1, 153-179 p.Chapter in book (Refereed)
    Abstract [en]

    Gas distribution models can provide comprehensive information about a large number of gas concentration measurements, highlighting, for example, areas of unusual gas accumulation. They can also help to locate gas sources and to plan where future measurements should be carried out. Current physical modeling methods, however, are computationally expensive and not applicable for real world scenarios with real-time and high resolution demands. This chapter reviews kernel methodsthat statistically model gas distribution. Gas measurements are treated as randomvariables, and the gas distribution is predicted at unseen locations either using akernel density estimation or a kernel regression approach. The resulting statistical 

    apmodelsdo not make strong assumptions about the functional form of the gas distribution,such as the number or locations of gas sources, for example. The majorfocus of this chapter is on two-dimensional models that provide estimates for themeans and predictive variances of the distribution. Furthermore, three extensionsto the presented kernel density estimation algorithm are described, which allow toinclude wind information, to extend the model to three dimensions, and to reflecttime-dependent changes of the random process that generates the gas distributionmeasurements. All methods are discussed based on experimental validation usingreal sensor data.

  • 57.
    Asiimwe, Edgar Napoleon
    et al.
    Örebro University, Örebro University School of Business.
    Grönlund, Åke
    Örebro University, Örebro University School of Business.
    On mobile learning with learning content management systems: a contemporary literature review2014In: Communications in Computer and Information Science, ISSN 1865-0929, E-ISSN 1865-0937, Vol. 479, 131-145 p.Article in journal (Refereed)
    Abstract [en]

    Learning Content management systems (LCMS) are important tools for organizing learning material and communication. Increasingly mobile technologies are used for internet access; particularly important in developing countries where broadband is scarce. Mobile LCMS introduce specific challenges, which are yet not fully addressed. This paper reviews the literature on mobile LCMS for the purpose of identifying current research focus, research gaps, and future research directions regarding how to bridge the gaps and leverage CMS technology to support "mobile learning". The concept matrix method is used to collect and analyze literature. Five prominent research areas are found; Use, access, design and infrastructure; communication and collaboration; engagement and knowledge development; content and service delivery; and implementation experiences and evaluation. A major gap identified is that research does neither clearly nor thoroughly address the intersection between learning and technology. Adjusting technologies to learning contexts and environments is a key area for future research.

  • 58.
    Bacciu, Davide
    et al.
    Dipartimento di Informatica, Università di Pisa, Italy.
    Gallicchio, Claudio
    Dipartimento di Informatica, Università di Pisa, Italy.
    Micheli, Alessio
    Dipartimento di Informatica, Università di Pisa, Italy.
    Di Rocco, Maurizio
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Learning context-aware mobile robot navigation in home environments2014In: IISA 2014: The 5th International Conference on Information, Intelligence, Systems and Applications, New York: Institute of Electrical and Electronics Engineers (IEEE), 2014, 57-62 p., 6878733Conference paper (Refereed)
    Abstract [en]

    We present an approach to make planning adaptive in order to enable context-aware mobile robot navigation. We integrate a model-based planner with a distributed learning system based on reservoir computing, to yield personalized planning and resource allocations that account for user preferences and environmental changes. We demonstrate our approach in a real robot ecology, and show that the learning system can effectively exploit historical data about navigation performance to modify the models in the planner, without any prior information oncerning the phenomenon being modeled. The plans produced by the adapted CL fail more rarely than the ones generated by a non-adaptive planner. The distributed learning system handles the new learning task autonomously, and is able to automatically identify the sensorial information most relevant for the task, thus reducing the communication and computational overhead of the predictive task.

  • 59. Bahadori, Shahram
    et al.
    Cesta, Amedeo
    Grisetti, Giorgio
    Iocchi, Luca
    Leone, Riccardo G.
    Nardi, Daniele
    Oddi, Angelo
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Robocare: an integrated robotic system for the domestic care of the elderly2003Conference paper (Refereed)
  • 60. Bahadori, Shahram
    et al.
    Cesta, Amedeo
    Grisetti, Giorgio
    Iocchi, Luca
    Leone, Riccardo G.
    Nardi, Daniele
    Oddi, Angelo
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Rasconi, Riccardo
    RoboCare: pervasive intelligence for the domestic care of the elderly2004In: Intelligenza Artificiale, ISSN 1724-8035, Vol. 1, no 1, 16-21 p.Article in journal (Refereed)
  • 61. Bahadori, Shahram
    et al.
    Cesta, Amedeo
    Iocchi, Luca
    Leone, Riccardo G.
    Nardi, Daniele
    Pecora, Federico
    Örebro University, Department of Technology.
    Rasconi, Riccardo
    Scozzafava, L.
    Towards ambient intelligence for the domestic care of the elderly2005In: Ambient intelligence: a novel paradigm / [ed] Gian Luca Foresti, Tim Ellis, Springer Berlin/Heidelberg, 2005, 15-38 p.Chapter in book (Refereed)
  • 62.
    Banaee, Hadi
    et al.
    Örebro University, School of Science and Technology.
    Ahmed, Mobyen Uddin
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    A framework for automatic text generation of trends in physiological time series data2013In: IEEE International Conference on Systems, Man, and Cybernetics, 13-16 Oct. 2013, Manchester, IEEE conference proceedings, 2013, 3876-3881 p.Conference paper (Refereed)
    Abstract [en]

    Health monitoring systems using wearable sensorshave rapidly grown in the biomedical community. The mainchallenges in physiological data monitoring are to analyse largevolumes of health measurements and to represent the acquiredinformation. Natural language generation is an effective methodto create summaries for both clinicians and patients as it candescribe useful information extracted from sensor data in textualformat. This paper presents a framework of a natural languagegeneration system that provides a text-based representation ofthe extracted numeric information from physiological sensorsignals. More specifically, a new partial trend detection algorithmis introduced to capture the particular changes and events ofhealth parameters. The extracted information is then representedconsidering linguistic characterisation of numeric features. Ex-perimental analysis was performed using a wearable sensor and demonstrates a possible output in natural language text.

  • 63.
    Banaee, Hadi
    et al.
    Örebro University, School of Science and Technology.
    Ahmed, Mobyen Uddin
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Data mining for wearable sensors in health monitoring systems: a review of recent trends and challenges2013In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 13, no 12, 17472-17500 p.Article in journal (Refereed)
    Abstract [en]

    The past few years have witnessed an increase in the development of wearable sensors for health monitoring systems. This increase has been due to several factors such as development in sensor technology as well as directed efforts on political and stakeholder levels to promote projects which address the need for providing new methods for care given increasing challenges with an aging population. An important aspect of study in such system is how the data is treated and processed. This paper provides a recent review of the latest methods and algorithms used to analyze data from wearable sensors used for physiological monitoring of vital signs in healthcare services. In particular, the paper outlines the more common data mining tasks that have been applied such as anomaly detection, prediction and decision making when considering in particular continuous time series measurements. Moreover, the paper further details the suitability of particular data mining and machine learning methods used to process the physiological data and provides an overview of the properties of the data sets used in experimental validation. Finally, based on this literature review, a number of key challenges have been outlined for data mining methods in health monitoring systems

  • 64.
    Banaee, Hadi
    et al.
    Örebro University, School of Science and Technology.
    Ahmed, Mobyen Uddin
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Descriptive Modelling of Clinical Conditions with Data-driven Rule Mining in Physiological Data2015In: Proceedings of the 8th International conference of Health Informatics (HEALTHINF 2015), SciTePress, 2015Conference paper (Refereed)
    Abstract [en]

    This paper presents an approach to automatically mine rules in time series data representing physiologicalparameters in clinical conditions. The approach is fully data driven, where prototypical patterns are mined foreach physiological time series data. The generated rules based on the prototypical patterns are then describedin a textual representation which captures trends in each physiological parameter and their relation to the otherphysiological data. In this paper, a method for measuring similarity of rule sets is introduced in order tovalidate the uniqueness of rule sets. This method is evaluated on physiological records from clinical classesin the MIMIC online database such as angina, sepsis, respiratory failure, etc.. The results show that the rulemining technique is able to acquire a distinctive model for each clinical condition, and represent the generatedrules in a human understandable textual representation

  • 65.
    Banaee, Hadi
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Data-driven rule mining and representation of temporal patterns in physiological sensor data2015In: IEEE journal of biomedical and health informatics, ISSN 2168-2194, E-ISSN 2168-2208, Vol. 19, no 5, 1557-1566 p.Article in journal (Refereed)
    Abstract [en]

    Mining and representation of qualitative patterns is a growing field in sensor data analytics. This paper leverages from rule mining techniques to extract and represent temporal relation of prototypical patterns in clinical data streams. The approach is fully data-driven, where the temporal rules are mined from physiological time series such as heart rate, respiration rate, and blood pressure. To validate the rules, a novel similarity method is introduced, that compares the similarity between rule sets. An additional aspect of the proposed approach has been to utilize natural language generation techniques to represent the temporal relations between patterns. In this study, the sensor data in the MIMIC online database was used for evaluation, in which the mined temporal rules as they relate to various clinical conditions (respiratory failure, angina, sepsis, ...) were made explicit as a textual representation. Furthermore, it was shown that the extracted rule set for any particular clinical condition was distinct from other clinical conditions.

  • 66.
    Banaee, Hadi
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Using Conceptual Spaces to Model Domain Knowledge in Data-to-Text Systems2014In: Proceedings of the 8th International Natural Language Generation Conference, Association for Computational Linguistics, 2014, 11-15 p.Conference paper (Refereed)
    Abstract [en]

    This position paper introduces the utilityof the conceptual spaces theory to conceptualisethe acquired knowledge in data-totextsystems. A use case of the proposedmethod is presented for text generationsystems dealing with sensor data. Modellinginformation in a conceptual spaceexploits a spatial representation of domainknowledge in order to perceive unexpectedobservations. This ongoing work aimsto apply conceptual spaces in NLG forgrounding numeric information into thesymbolic representation and confrontingthe important step of acquiring adequateknowledge in data-to-text systems.

  • 67.
    Bazzan, Ana L. C.
    et al.
    UFRGS, Porto Alegre, Brazil.
    de Oliveira, Denise
    UFRGS, Porto Alegre, Brazil.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Nagel, Kai
    TU Berlin.
    To adapt or not to adapt: consequences of adapting driver and traffic light agents2008In: Adaptive agents and multi-agent systems III: adaptation and multi-agent learning : 5th, 6th, and 7th European Symposium,ALAMAS 2005-2007on Adaptive and Learning Agents and Multi-Agent Systems : revised selected papers / [ed] Karl Tuyls, Ann Nowe, Zahia Guessoum, New York: Springer , 2008, 1-14 p.Conference paper (Refereed)
    Abstract [en]

    One way to cope with the increasing traffic demand is to integrate standard solutions with more intelligent control measures. However, the result of possible interferences between intelligent control or information provision tools and other components of the overall traffic system is not easily predictable. This paper discusses the effects of integrating co-adaptive decision-making regarding route choices (by drivers) and control measures (by traffic lights). The motivation behind this is that optimization of traffic light control is starting to be integrated with navigation support for drivers. We use microscopic, agent-based modelling and simulation, in opposition to the classical network analysis, as this work focuses on the effect of local adaptation. In a scenario that exhibits features comparable to real-world networks, we evaluate different types of adaptation by drivers and by traffic lights, based on local perceptions. In order to compare the performance, we have also used a global level optimization method based on genetic algorithms.

  • 68.
    Bazzan, Ana L. C.
    et al.
    Instituto de Informática/PPGC, UFRGS, Porto Alegre, RS, Brazil.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    A review on agent-based technology for traffic and transportation2014In: Knowledge engineering review (Print), ISSN 0269-8889, E-ISSN 1469-8005, Vol. 29, no 3, 375-403 p.Article, review/survey (Refereed)
    Abstract [en]

    In the last few years, the number of papers devoted to applications of agent-based technologies to traffic and transportation engineering has grown enormously. Thus, it seems to be the appropriate time to shed light over the achievements of the last decade, on the questions that have been successfully addressed, as well as on remaining challenging issues. In the present paper, we review the literature related to the areas of agent-based traffic modelling and simulation, and agent-based traffic control and management. Later we discuss and summarize the main achievements and the challenges.

  • 69.
    Bazzan, Ana L. C.
    et al.
    UFRGS, Porto Alegre, Brazil.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Re-routing agents in an abstract traffic scenario2008In: Advances in artificial intelligence: SBIA 2008 / [ed] Gerson Zaverucha, Augusto Loureiro da Costa, Berlin: Springer , 2008, 63-72 p.Conference paper (Refereed)
    Abstract [en]

    Human drivers may perform replanning when facing traffic jams or when informed that there are expected delays on their planned routes. In this paper, we address the effects of drivers re-routing, an issue that has been ignored so far. We tackle re-routing scenarios, also considering traffic lights that are adaptive, in order to test whether such a form of co-adaptation may result in interferences or positive cumulative effects. An abstract route choice scenario is used which resembles many features of real world networks. Results of our experiments show that re-routing indeed pays off from a global perspective as the overall load of the network is balanced. Besides, re-routing is useful to compensate an eventual lack of adaptivity regarding traffic management.

  • 70.
    Bazzan, Ana Lucia
    et al.
    Universidade Federal do Rio Grande do Sul (UFRGS), Brazil .
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Introduction to Intelligent Systems in Traffic and Transportation2013Book (Refereed)
    Abstract [en]

    Urban mobility is not only one of the pillars of modern economic systems, but also a key issue in the quest for equality of opportunity, once it can improve access to other services. Currently, however, there are a number of negative issues related to traffic, especially in mega-cities, such as economical issues (cost of opportunity caused by delays), environmental (externalities related to emissions of pollutants), and social (traffic accidents). Solutions to these issues are more and more closely tied to information and communication technology. Indeed, a search in the technical literature (using the keyword ``urban traffic" to filter out articles on data network traffic) retrieved the following number of articles (as of December 3, 2013): 9,443  (ACM Digital Library), 26,054 (Scopus), and 1,730,000 (Google Scholar). Moreover, articles listed in the ACM query relate to conferences as diverse as MobiCom, CHI, PADS, and AAMAS. This means that  there is a big and diverse community of computer scientists and computer engineers who tackle research that is connected to the development of intelligent traffic and transportation systems. It is also possible to see that this community is growing, and that research projects are getting more and more interdisciplinary. To foster the cooperation among the involved communities, this book aims at  giving a broad introduction into the basic but relevant concepts related to transportation systems, targeting researchers and practitioners from computer science and information technology. In addition, the second part of the book gives a panorama of some of the most exciting and newest technologies, originating in computer science and computer engineering, that are now being employed in projects related to car-to-car communication, interconnected vehicles, car navigation, platooning, crowd sensing and sensor networks, among others. This material will also be of interest to engineers and researchers from the traffic and transportation community.

  • 71. Beetz, Michael
    et al.
    Chatila, Raja
    Hertzberg, Joachim
    Pecora, Federico
    Örebro University, School of Science and Technology.
    AI Reasoning Methods for Robotics2016In: Springer Handbook of Robotics / [ed] Bruno Siciliano, Oussama Khatib, Springer, 2016, 2, 329-356 p.Chapter in book (Other academic)
    Abstract [en]

    Artificial intelligence (AI) reasoning technology involving, e.g., inference, planning, and learning, has a track record with a healthy number of successful applications. So can it be used as a toolbox of methods for autonomous mobile robots? Not necessarily, as reasoning on a mobile robot about its dynamic, partially known environment may differ substantially from that in knowledge-based pure software systems, where most of the named successes have been registered. Moreover, recent knowledge about the robot’s environment cannot be given a priori, but needs to be updated from sensor data, involving challenging problems of symbol grounding and knowledge base change. This chapter sketches the main robotics relevant topics of symbol-based AI reasoning. Basic methods of knowledge representation and inference are described in general, covering both logic and probability-based approaches. The chapter first gives a motivation by example, to what extent symbolic reasoning has the potential of helping robots perform in the first place. Then (Sect. 14.2), we sketch the landscape of representation languages available for the endeavor. After that (Sect. 14.3), we present approaches and results for several types of practical, robotics-related reasoning tasks, with an emphasis on temporal and spatial reasoning. Plan-based robot control is described in some more detail in Sect. 14.4. Section 14.5 concludes.

  • 72. Benedetti, Marco
    et al.
    Pecora, Federico
    Örebro University, Department of Technology.
    Policella, Nicola
    Anatomy of a scheduling competition2007Conference paper (Refereed)
  • 73.
    Benferhat, Salem
    et al.
    Univ. Paul Sabatier, Toulouse, France.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Smets, Philippe
    Univ. Libre de Bruxelles, Brussels, Belgium.
    Belief functions and default reasoning2000In: Artificial Intelligence, ISSN 0004-3702, E-ISSN 0374-2539, Vol. 122, no 1-2, 1-69 p.Article in journal (Refereed)
    Abstract [en]

    We present a new approach to deal with default information based on the theory of belief functions. Our semantic structures, inspired by Adams' epsilon semantics, are epsilon-belief assignments, where mass values are either close to 0 or close to 1. In the first part of this paper, we show that these structures can be used to give a uniform semantics to several popular non-monotonic systems, including Kraus, Lehmann and Magidor's system P, Pearl's system Z, Brewka's preferred sub-theories, Geffner's conditional entailment, Pinkas' penalty logic, possibilistic logic, and the lexicographic approach. In the second part, we use epsilon-belief assignments to build a new system, called LCD, and we show that this system correctly addresses the well-known problems of specificity, irrelevance, blocking of inheritance, ambiguity, and redundancy

  • 74.
    Berglund, Erik
    et al.
    Örebro University, School of Science and Technology.
    Iliev, Boyko
    Örebro University, School of Science and Technology.
    Palm, Rainer
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Charusta, Krzysztof
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar
    Örebro University, School of Science and Technology.
    Mapping between different kinematic structures without absolute positioning during operation2012In: Electronics Letters, ISSN 0013-5194, E-ISSN 1350-911X, Vol. 48, no 18, 1110-1112 p.Article in journal (Refereed)
    Abstract [en]

    When creating datasets for modelling of human skills based on training examples from human motion, one can encounter the problem that the kinematics of the robot does not match the human kinematics. Presented is a simple method of bypassing the explicit modelling of the human kinematics based on a variant of the self-organising map (SOM) algorithm. While the literature contains instances of SOM-type algorithms used for dimension reduction, this reported work deals with the inverse problem: dimension increase, as we are going from 4 to 5 degrees of freedom.

  • 75.
    Bergstedt, Martin
    et al.
    Örebro University, School of Science and Technology.
    Gillström, Tobias
    Örebro University, School of Science and Technology.
    Observator för frontlinjen på surfplatta2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been carried out at Saab Dynamics. The project's purpose was to develop an application, TBFO, for reporting information containing how the missile GLSDB would strike a target. TBFO is intended to be used in the proximity of the target and information is sent to the planning system GLSDB MPS.

    The application was built around the 3D engine from Vricon and is developed to fit for use of touch devices. The main part of the work concerns the development of user interface for touch input and the system’s application protocol.

    This report describes the processes of developing the system, including what tools and methods that have been used during development. The report also provides an in-depth look at processes used when developing applications for touch devices.

    The conclusion from the results of this project is that the idea of the described system is useful for the process of planning an assault with GLSDB MPS.

  • 76.
    Bergsten, Pontus
    Örebro University, Department of Technology.
    Observers and controllers for Takagi-Sugeno fuzzy systems2001Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis studies analysis and design issues for observers anc controllers for Takagi-Sugeno (TS) fuzzy systems. Many physical systems are nonlinear in nature and using the well known linear techniques for such systems may result in bad performance, and even instability. On the other hand, analysis and design of observers and controllers for general nonlinear systems tend to be a quite involved procedure. It turns out, however, that a TS fuzzy system is able to represent or approximate a large class of nonlinear systems. Developing methods for observation and control for TS systems should therefore be worthwile.

    The TS fuzzy systems considered in this thesis are allowed to have an affine term. This can be an advantage, because affine TS fuzzy systems may be able to approximate nonlinear functions  to high accuracy with fewer rules than the TS fuzzy system with linear consequents only.

    It is shown that observer design is more difficult when the weights in the TS fuzzy systems depend on the estimated state, and an explicit design procedure is devised for that case. A reduced order observer is also proposed. To deal with modeling errors a fuzzy sliding mode approach is taken.

    The controller design is focused on affine TS fuzzy systems. Analysis and design of observer-based error state feedback controllers are proposed. Furthermore, it is also shown how recent results on classical gain scheduling may be used for control of affine TS fuzzy systems.

    Analysis and design for both observers and controllers are based on quadratic stability analysis, and in some cases, on robust quadratic stability analysis. Although this approach may be conservative, it often results in automatic design procedures based on optimization subject to linear matrix inequalities.

  • 77.
    Bergsten, Pontus
    et al.
    Örebro University, School of Science and Technology.
    Palm, Rainer
    Siemens AG Corporate Technology, Otto-Hahn-Ring, Munich, German.
    Driankov, Dimiter
    Örebro University, School of Science and Technology.
    Observers for Takagi-Sugeno fuzzy systems2002In: IEEE transactions on systems, man and cybernetics. Part B. Cybernetics, ISSN 1083-4419, E-ISSN 1941-0492, ISSN 1083-4419/02, Vol. 32, no 1, 114-121 p.Article in journal (Refereed)
    Abstract [en]

    We focus on the analysis and design of two different sliding mode observers for dynamic Takagi-Sugeno (TS) fuzzy systems. A nonlinear system of this class is composed of multiple affine local linear models that are smoothly interpolated by weighting functions resulting from a fuzzy partitioning of the state space of a given nonlinear system subject to observation. The Takagi-Sugeno fuzzy system is then an accurate approximation of the original nonlinear system. Our approach to the analysis and design of observers for Takagi-Sugeno fuzzy systems is based on extending sliding mode observer schemes to the case of interpolated multiple local affine linear models. Thus, our main contribution is nonlinear observer analysis and design methods that can effectively deal with model/plant mismatches. Furthermore, we consider the difficult case when the weighting functions in the Takagi-Sugeno fuzzy system depend on the estimated state

  • 78.
    Berna, Amalia
    et al.
    CSIRO Ecosystem Sciences and CSIRO Food Futures Flagship, ACT, Australia.
    Vergara, Alexander
    University of California San Diego, USA.
    Trincavelli, Marco
    Örebro University, School of Science and Technology.
    Huerta, Ramon
    University of California San Diego, USA.
    Afonja, Ayo
    Department of Chemistry, University College London, London, UK.
    Parkin, Ivan
    Binions, Russell
    Trowell, Stephen
    Evaluating zeolite-modified sensors: towards a faster set of chemical sensors2011In: Olfaction and electronic nose: proceedings of the 14th International Symposium on Olfaction and Electronic Nose (ISOEN 2011), May 2-5, 2011, New York City, USA, 2011, 50-52 p.Conference paper (Refereed)
    Abstract [en]

    The response of zeolite-modified sensors, prepared by screen printing layers of chromium titanium oxide (CTO), were compared to unmodified tin oxide sensors using amplitude and transient responses. For transient responses we used a family of features, derived from the exponential moving average (EMA), to characterize chemo-resistive responses. All sensors were tested simultaneously against 20 individual volatile compounds from four chemical groups. The responses of the two types of sensors showed some independence. The zeolite modified CTO sensors discriminated compounds better using either amplitude response or EMA features and CTO-modified sensors also responded three times faster.

  • 79.
    Besold, Tarek R.
    et al.
    Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany.
    Kuehnberger, Kai-Uwe
    Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany.
    Garcez, Artur d'Avila
    City University London, London, UK.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Fischer, Martin H.
    University of Potsdam, Potsdam, Germany.
    Bundy, Alan
    University of Edinburgh, Edinburgh, Scotland.
    Anchoring Knowledge in Interaction: Towards a Harmonic Subsymbolic/Symbolic Framework and Architecture of Computational Cognition2015In: Artificial General Intelligence (AGI 2015), Springer, 2015, 35-45 p.Conference paper (Refereed)
    Abstract [en]

    We outline a proposal for a research program leading to a new paradigm, architectural framework, and prototypical implementation, for the cognitively inspired anchoring of an agent's learning, knowledge formation, and higher reasoning abilities in real-world interactions: Learning through interaction in real-time in a real environment triggers the incremental accumulation and repair of knowledge that leads to the formation of theories at a higher level of abstraction. The transformations at this higher level filter down and inform the learning process as part of a permanent cycle of learning through experience, higher-order deliberation, theory formation and revision.

    The envisioned framework will provide a precise computational theory, algorithmic descriptions, and an implementation in cyber-physical systems, addressing the lifting of action patterns from the subsymbolic to the symbolic knowledge level, effective methods for theory formation, adaptation, and evolution, the anchoring of knowledge-level objects, realworld interactions and manipulations, and the realization and evaluation of such a system in different scenarios. The expected results can provide new foundations for future agent architectures, multi-agent systems, robotics, and cognitive systems, and can facilitate a deeper understanding of the development and interaction in human-technological settings.

  • 80.
    Bidot, Julien
    et al.
    Universität Ulm, Ulm, Germany.
    Biundo, Susanne
    Universität Ulm, Ulm, Germany.
    Artificial intelligence planning for ambient environments2011In: Next generation intelligent environments: ambient adaptive systems / [ed] Wolfgang Minker, Tobias Heinroth, Springer Science+Business Media B.V., 2011, 1, 195-225 p.Chapter in book (Refereed)
    Abstract [en]

    In this chapter, we describe how Artificial Intelligence planning techniques are used in The Adapted and TRusted Ambient eCOlogies (ATRACO) in order to provide Sphere Adaptation. We introduce the Planning Agent (PA) which plays a central role in the realization and the structural adaptation of activity spheres. Based on particular information included in the ontology of the execution environment, the PA delivers workflows that consist of the basic activities to be executed in order to achieve a user's goals. The PA encapsulates a search engine for hybrid planning--the combination of hierarchical task network planning and partial-order causal-link planning. In this chapter, we describe a formal framework and a development platform for hybrid planning, PANDA. This platform allows for the implementation of many search strategies, and we explain how we realize the search engine of the PA by adapting and configuring PANDA specifically for addressing planning problems that are part of the ATRACO service composition. We describe how the PA interacts with the Sphere Manager and the Ontology Manager in order to create planning problems dynamically and generate workflows in the ATRACO-BPEL language. In addition, an excerpt of a planning domain for ATRACO is provided.

  • 81.
    Bidot, Julien
    et al.
    Universität Ulm, Ulm, Germany.
    Biundo, Susanne
    Universität Ulm, Ulm, Germany.
    Heinroth, Tobias
    Universität Ulm, Ulm, Germany.
    Minker, Wolfgang
    Universität Ulm, Ulm, Germany.
    Nothdurft, Florian
    Universität Ulm, Ulm, Germany.
    Schattenberg, Bernd
    Universität Ulm, Ulm, Germany.
    Verbal plan explanations for hybrid planning2010In: MKWI / [ed] Matthias Schumann, Lutz M. Kolbe, Michael H. Breitner, and Arne Frerichs, Universitätsverlag Göttingen, 2010, 2309-2320 p.Conference paper (Refereed)
  • 82.
    Bidot, Julien
    et al.
    Universität Ulm, Ulm, Germany.
    Biundo, Susanne
    Universität Ulm, Ulm, Germany.
    Schattenberg, Bernd
    Universität Ulm, Ulm, Germany.
    Plan repair in hybrid planning2008In: KI 2008: Advances in Artificial Intelligence / [ed] Andreas R. Dengel, Karsten Berns, Thomas M. Breuel, Frank Bomarius, and Thomas R. Roth-Berghofer, Springer, 2008, 169-176 p.Conference paper (Refereed)
    Abstract [en]

    We present a domain-independent approach to plan repair in a formal framework for hybrid planning. It exploits the generation process of the failed plan by retracting decisions that led to the failed plan fragments. They are selectively replaced by suitable alternatives, and the repaired plan is completed by following the previous generation process as close as possible. This way, a stable solution is obtained, i.e. a repair of the failed plan that causes minimal perturbation.

  • 83.
    Bidot, Julien
    et al.
    Universität Ulm, Ulm, Germany.
    Goumopoulos, Christos
    DAISy Research Unit, Patras, Greece.
    Calemis, Ioannis
    DAISy Research Unit, Patras, Greece.
    Using AI planning and late binding for managing service workflows in intelligent environments2011In: 2011 IEEE International conference on pervasive computing and communications (PerCom), IEEE conference proceedings, 2011, 156-163 p.Conference paper (Refereed)
    Abstract [en]

    In this paper, we present an approach to aggregating and using devices that support the everyday life of human users in ambient intelligence environments. These execution environments are complex and changing over time, since the devices of the environments are numerous and heterogeneous, and they may appear or disappear at any time. In order to appropriately adapt the ambient system to a user's needs, we adopt a service-oriented approach; i.e., devices provide services that reflect their capabilities. The orchestration of the devices is actually realized with the help of Artificial Intelligence planning techniques and dynamic service binding. At design time, (i) a planning problem is created that consists of the user's goal to be achieved and the services currently offered by the intelligent environment, (ii) the planning problem is then solved using Hierarchical Task Network and Partial-Order Causal-Link planning techniques, (iii) and from the planning decisions taken to find solution plans, abstract service workflows are automatically generated. At run time, the abstract services are dynamically bound to devices that are actually present in the environment. Adaptation of the workflow instantiation is possible due to the late binding mechanism employed. The paper depicts the architecture of our system. It also describes the modeling and the life cycle of the workflows. We discuss the advantages and the limit of our approach with respect to related work and give specific details about implementation. We present some experimental results that validate our system in a real-world application scenario.

  • 84. Bidot, Julien
    et al.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Lagriffoul, Fabien
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Geometric backtracking for combined task and motion planning in robotic systems2017In: Artificial Intelligence, ISSN 0004-3702, E-ISSN 1872-7921, Vol. 247, 229-265 p.Article in journal (Refereed)
    Abstract [en]

    Planners for real robotic systems should not only reason about abstract actions, but also about aspects related to physical execution such as kinematics and geometry. We present an approach to hybrid task and motion planning, in which state-based forward-chaining task planning is tightly coupled with motion planning and other forms of geometric reasoning. Our approach is centered around the problem of geometric backtracking that arises in hybrid task and motion planning: in order to satisfy the geometric preconditions of the current action, a planner may need to reconsider geometric choices, such as grasps and poses, that were made for previous actions. Geometric backtracking is a necessary condition for completeness, but it may lead to a dramatic computational explosion due to the large size of the space of geometric states. We explore two avenues to deal with this issue: the use of heuristics based on different geometric conditions to guide the search, and the use of geometric constraints to prune the search space. We empirically evaluate these different approaches, and demonstrate that they improve the performance of hybrid task and motion planning. We demonstrate our hybrid planning approach in two domains: a real, humanoid robotic platform, the DLR Justin robot, performing object manipulation tasks; and a simulated autonomous forklift operating in a warehouse.

  • 85.
    Bidot, Julien
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Lagriffoul, Fabien
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Geometric backtracking for combined task and path planning in robotic systemsManuscript (preprint) (Other academic)
    Abstract [en]

    Planners for real, possibly complex, robotic systems should not only reason about abstract actions, but also about aspects related to physical execution such as kinematics and geometry. We present an approach in which state-based forward-chaining task planning is tightly coupled with sampling-based motion planning and other forms of geometric reasoning. We focus on the problem of geometric backtracking which arises when a planner needs to reconsider geometric choices, like grasps and poses, that were made for previous actions, in order to satisfy geometric preconditions of the current action. Geometric backtracking is a necessary condition for completeness, but it may lead to a dramatic computational explosion due to the systematic exploration of the space of geometric states. In order to deal with that, we introduce heuristics based on the collisions between the robot and movable objects detected during geometric backtracking and on kinematic relations between actions. We also present a complementary approach based on propagating explicit constraints which are automatically generated from the symbolic actions to be evaluated and from the kinematic model of the robot. We empirically evaluate these dierent approaches. We demonstrate our planner on a real advanced robot, the DLR Justin robot, and on a simulated autonomous forklift. 

  • 86.
    Bidot, Julien
    et al.
    Ecole Nationale d'Ingénieurs de Tarbes, Tarbes, France.
    Laborie, Philippe
    ILOG S.A., Gentilly, France.
    Beck, J. Christopher
    University of Toronto, Toronto, Canada.
    Vidal, Thierry
    Ecole Nationale d'Ingénieurs de Tarbes, Tarbes, France.
    Using constraint programming and simulation for execution monitoring and progressive scheduling2006In: Information control problems in manufacturing 2006 / [ed] Alexandre Dolgui, Gérard Morel, Carlos E. Pereira, Elsevier, 2006, 615-620 p.Conference paper (Refereed)
    Abstract [en]

    The problem we tackle is progressive scheduling with temporal and resource uncertainty. Operation durations are imprecise and alternative resources may break down. Operation end times and resource breakdowns are observed during execution. In this paper, we assume we have a representation of uncertainty in the form of probability distributions which are used in the simulation of schedule execution. We generate the schedule piece by piece during execution and use simulation to monitor the execution of the partial schedule. This paper describes the basis on which the decision to select and schedule a new subset of operations is made.

  • 87.
    Bidot, Julien
    et al.
    Ecole Nationale d'Ingénieurs de Tarbes, Tarbes, France.
    Laborie, Philippe
    ILOG S.A., Gentilly, France.
    Beck, J. Christopher
    University College Cork, Cork, Ireland.
    Vidal, Thierry
    Ecole Nationale d'Ingénieurs de Tarbes, Tarbes, France.
    Using simuation for execution monitoring and on-line rescheduling with uncertain durations2003Conference paper (Refereed)
    Abstract [en]

    The problem we tackle is on-line rescheduling with temporal uncertainty, activity durations are uncertain and activity end times must be observed during execution. In this paper, we will assume we have a representation of the uncertainty of each activity duration in the form of probability distributions which are used in the simulation of schedule execution. We use the simulations to monitor the execution of the schedule and in particular to estimate the quality of the schedule and the end times of the activities. Given an initial schedule, the schedule starts execution and we must decide when to reschedule. We propose and explore a non-monotonic technique where each time we reschedule we can completely change the existing schedule except for those activities that have already started (or finished) execution. This paper explicitly addresses the basis on which the decision to reschedule is made by investigating three simple measures of the data provided by simulation.

  • 88.
    Bidot, Julien
    et al.
    Universität Ulm, Ulm, Germany.
    Vidal, Thierry
    Ecole Nationale d'Ingénieurs de Tarbes, Tarbes, France.
    Laborie, Philippe
    ILOG S.A., Gentilly, France.
    Beck, J. Christopher
    University of Toronto, Toronto, Canada.
    A general framework for scheduling in a stochastic environment2007In: / [ed] Manuela M. Veloso, 2007, 56-61 p.Conference paper (Refereed)
    Abstract [en]

    There are many systems and techniques that address stochastic scheduling problems, based on distinct and sometimes opposite approaches, especially in terms of how scheduling and schedule execution are combined, and if and when knowledge about the uncertainties are taken into account. In many real-life problems, it appears that all these approaches are needed and should be combined, which to our knowledge has never been done. Hence it it first desirable to define a thorough classification of the techniques and systems, exhibiting relevant features: in this paper, we propose a three-dimension typology that distinguishes between proactive, progressive, and revision techniques. Then a theoretical representation model integrating those three distinct approaches is defined. This model serves as a general template within which parameters can be tuned to implement a system that will fit specific application needs: we briefly introduce in this paper our first experimental prototypes which validate our model.

  • 89.
    Bidot, Julien
    et al.
    Universität Ulm, Ulm, Germany.
    Vidal, Thierry
    IRISA-INRIA, Rennes, France.
    Laborie, Philippe
    ILOG S.A., Gentilly, France.
    Beck, J. Christopher
    University of Toronto, Toronto, Canada.
    A theoretic and practical framework for scheduling in a stochastic environment2009In: Journal of Scheduling, ISSN 1094-6136, E-ISSN 1099-1425, Vol. 12, no 3, 315-344 p.Article in journal (Refereed)
    Abstract [en]

    There are many systems and techniques that address stochastic planning and scheduling problems, based on distinct and sometimes opposite approaches, especially in terms of how generation and execution of the plan, or the schedule, are combined, and if and when knowledge about the uncertainties is taken into account. In many real-life problems, it appears that many of these approaches are needed and should be combined, which to our knowledge has never been done. In this paper, we propose a typology that distinguishes between proactive, progressive, and revision approaches. Then, focusing on scheduling and schedule execution, a theoretic model integrating those three approaches is defined. This model serves as a general template to implement a system that will fit specific application needs: we introduce and discuss our experimental prototypes which validate our model in part, and suggest how this framework could be extended to more general planning systems.

  • 90.
    Biel, Lena
    Örebro University, Department of Technology.
    Modeling of perceptual systems: a sensor fusion model with active perception2002Licentiate thesis, comprehensive summary (Other academic)
    List of papers
    1. ECG analysis: a new approach in human identification
    Open this publication in new window or tab >>ECG analysis: a new approach in human identification
    2001 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    In this paper a new approach in human identification is investigated, For this purpose, a standard 12-lead electrocardiogram (ECG) recorded during rest is used. Selected features extracted from the ECG are used to identify a person in a predetermined group. Multivariate analysis is used for the identification task. Experiments show that it is possible to identify a person by features extracted from one lead only. Hence, only three electrodes have to be attached on the person to be identified. This makes the method applicable without too much effort.

    Keyword
    data fusion, electrocardiogram (ECG), feature extraction, human identification, multivariate analysis
    National Category
    Computer Science
    Research subject
    Computer and Systems Science
    Identifiers
    urn:nbn:se:oru:diva-16067 (URN)000169439600022 ()
    Available from: 2011-06-22 Created: 2011-06-22 Last updated: 2017-10-17Bibliographically approved
    2. Multivariate sensor fusion by a neural network model
    Open this publication in new window or tab >>Multivariate sensor fusion by a neural network model
    (English)Manuscript (preprint) (Other academic)
    National Category
    Computer Science
    Research subject
    Computer and Systems Science
    Identifiers
    urn:nbn:se:oru:diva-16070 (URN)
    Available from: 2011-06-22 Created: 2011-06-22 Last updated: 2017-10-17Bibliographically approved
    3. Active perception for autonomous sensor systems: an emerging paradigm?
    Open this publication in new window or tab >>Active perception for autonomous sensor systems: an emerging paradigm?
    2000 (English)Manuscript (preprint) (Other academic)
    National Category
    Computer Science
    Research subject
    Computer and Systems Science
    Identifiers
    urn:nbn:se:oru:diva-16068 (URN)000165444800008 ()
    Available from: 2011-06-22 Created: 2011-06-22 Last updated: 2017-10-17Bibliographically approved
    4. Active perception in a sensor fusion model
    Open this publication in new window or tab >>Active perception in a sensor fusion model
    2002 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    During the last decades the research in the sensor fusion area has mainly been focused on fusion methods and feature selection methods. A possible further development in this area is to incorporate a process referred to as active perception. This means that the system is able to manipulate the sensing mechanisms to create a focus on selected information in the surrounding environment. This process may also be able to handle the feature selection process with respect to which features to be used and/or the number of features to use. This paper presents a model that contains a decision system based on active perception integrated with previous sensor fusion algorithms. The human body has perhaps one of the most advanced perceptual processing systems. The human perception process can be divided into sensation (measurement collection) and perception (interpret the surroundings). During the sensation process a huge amount of data is collected from different sensors that reflect the environment. The information has to be interpreted in an effective way, i.e. in the fusion process. The interpretation together with a decision system to control the sensors to focus on important information will correspond to the (active) perception process. The model presented in this paper capitalizes on the properties presented by the biological counterpart to achieve more human-like processes for a sensor fusion. Finally, the paper presents the testing of the model in two examples. The applications used have a safety approach of fire indication, identification and decision-making. The goal is to enlarge a conventional fire alarm system to not only detect fire, but also to propose different actions for a human in a dangerous area for example.

    National Category
    Computer Science
    Research subject
    Computer and Systems Science
    Identifiers
    urn:nbn:se:oru:diva-16066 (URN)000176995000017 ()
    Available from: 2011-06-22 Created: 2011-06-22 Last updated: 2017-10-17Bibliographically approved
  • 91.
    Biel, Lena
    et al.
    Örebro University, Department of Technology.
    Pettersson, Ola
    Örebro University, Department of Technology.
    Philipson, Lennart
    Örebro University, Department of Technology.
    Wide, Peter
    Örebro University, Department of Technology.
    ECG analysis: a new approach in human identification2001Manuscript (preprint) (Other academic)
    Abstract [en]

    In this paper a new approach in human identification is investigated, For this purpose, a standard 12-lead electrocardiogram (ECG) recorded during rest is used. Selected features extracted from the ECG are used to identify a person in a predetermined group. Multivariate analysis is used for the identification task. Experiments show that it is possible to identify a person by features extracted from one lead only. Hence, only three electrodes have to be attached on the person to be identified. This makes the method applicable without too much effort.

  • 92.
    Biel, Lena
    et al.
    Örebro University, Department of Technology.
    Wide, Peter
    Örebro University, Department of Technology.
    Active perception for autonomous sensor systems: an emerging paradigm?2000Manuscript (preprint) (Other academic)
  • 93.
    Biel, Lena
    et al.
    Örebro University, Department of Technology.
    Wide, Peter
    Örebro University, Department of Technology.
    Active perception in a sensor fusion model2002Manuscript (preprint) (Other academic)
    Abstract [en]

    During the last decades the research in the sensor fusion area has mainly been focused on fusion methods and feature selection methods. A possible further development in this area is to incorporate a process referred to as active perception. This means that the system is able to manipulate the sensing mechanisms to create a focus on selected information in the surrounding environment. This process may also be able to handle the feature selection process with respect to which features to be used and/or the number of features to use. This paper presents a model that contains a decision system based on active perception integrated with previous sensor fusion algorithms. The human body has perhaps one of the most advanced perceptual processing systems. The human perception process can be divided into sensation (measurement collection) and perception (interpret the surroundings). During the sensation process a huge amount of data is collected from different sensors that reflect the environment. The information has to be interpreted in an effective way, i.e. in the fusion process. The interpretation together with a decision system to control the sensors to focus on important information will correspond to the (active) perception process. The model presented in this paper capitalizes on the properties presented by the biological counterpart to achieve more human-like processes for a sensor fusion. Finally, the paper presents the testing of the model in two examples. The applications used have a safety approach of fire indication, identification and decision-making. The goal is to enlarge a conventional fire alarm system to not only detect fire, but also to propose different actions for a human in a dangerous area for example.

  • 94.
    Biundo, Susanne
    et al.
    Universität Ulm, Ulm, Germany.
    Bidot, Julien
    Universität Ulm, Ulm, Germany.
    Schattenberg, Bernd
    Universität Ulm, Ulm, Germany.
    Planning in the real world2011In: Informatik-Spektrum, ISSN 0170-6012, E-ISSN 1432-122X, Vol. 34, no 5, 443-454 p.Article in journal (Refereed)
    Abstract [en]

    In this article, we describe how real world planning problems can be solved by employing Artificial Intelligence planning techniques. We introduce the paradigm of hybrid planning, which is particularly suited for applications where plans are not intended to be automatically executed by systems, but are made for humans. Hybrid planning combines hierarchical planning – the stepwise refinement of complex tasks – with explicit reasoning about causal dependencies between actions, thereby reflecting exactly the kinds of reasoning humans perform when developing plans. We show how plans are generated and how failed plans are repaired in a way that guarantees stability. Our illustrating examples are taken from a domain model for disaster relief missions enforced upon extensive floods. Finally, we present a tool to support the challenging task of constructing planning domain models.

    The article ends with an overview of a wide varity of actual planning applications and outlines further such in the area of cognitive technical systems.

  • 95.
    Blanco, Jose Luis
    et al.
    University of Màlaga, Màlaga, Spain.
    Monroy, Javier G.
    University of Màlaga, Màlaga, Spain.
    Gonzalez-Jimenez, Javier
    University of Màlaga, Màlaga, Spain.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    A Kalman Filter Based Approach To Probabilistic Gas Distribution Mapping2013Conference paper (Refereed)
    Abstract [en]

    Building a model of gas concentrations has important indus-trial and environmental applications, and mobile robots ontheir own or in cooperation with stationary sensors play animportant role in this task. Since an exact analytical de-scription of turbulent flow remains an intractable problem,we propose an approximate approach which not only esti-mates the concentrations but also their variances for eachlocation. Our point of view is that of sequential Bayesianestimation given a lattice of 2D cells treated as hidden vari-ables. We first discuss how a simple Kalman filter pro-vides a solution to the estimation problem. To overcomethe quadratic computational complexity with the mappedarea exhibited by a straighforward application of Kalmanfiltering, we introduce a sparse implementation which runsin constant time. Experimental results for a real robot vali-date the proposed method.

  • 96. Bloch, I.
    et al.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    On the representation of fuzzy spatial relations in robot maps2003In: Intelligent systems for information processing: from representation to applications / [ed] Bernadette Bouchon-Meunier, Laurent Foulloy, Ronald R. Yager, Amsterdam: Elsevier, 2003, 47-57 p.Conference paper (Refereed)
    Abstract [en]

    Spatial directional relations, like "north of," play an important role in the modeling of the environment by an autonomous robot. We propose an approach to represent spatial relations grounded in fuzzy set theory and fuzzy mathematical morphology. We show how this approach can be applied to robot maps, and suggest that these relations can be used for self-localization and for reasoning about the environment. We illustrate our approach on real data collected by a mobile robot in an office environment

  • 97. Bloch, Isabelle
    et al.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Why robots should use fuzzy mathematical morphology2002Conference paper (Refereed)
    Abstract [en]

    Mobile robots must represent and reason about spatial knowledge acquired from sensor data which are inherently approximate and uncertain. While techniques based on fuzzy sets are increasingly used in this domain, the use of these techniques often rests on intuitive grounds. In this paper, we show that fuzzy mathematical morphology, a theory often used in image processing but mostly ignored in the robotic tradition, can provide a well grounded approach to the treatment of imprecise spatial knowledge in robotics

  • 98.
    Boldrin, Luca
    et al.
    University of Pauda.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    A modal logic for fusing partial belief of multiple reasoners1999In: Journal of logic and computation (Print), ISSN 0955-792X, E-ISSN 1465-363X, Vol. 9, no 1, 81-103 p.Article in journal (Refereed)
    Abstract [en]

    We present PLn, a multi-agent epistemic logic in which each agent can perform uncertain (possibilistic) reasoning. The original feature of this logic is the presence of a distributed belief operator, with the purpose of merging the belief of different agents. Unlike the corresponding operator in the categorical (non-uncertain) case, our distributed belief operator accumulates support for the same fact coming from different agents. This means that opinions shared by different agents can be combined into a stronger distributed belief. This feature is useful in problems like pooling expert opinions and combining information from multiple unreliable sources. We provide a possible worlds semantics and an axiomatic calculus for our logic, and prove soundness, completeness and decidability results. We hint at some possible applications of PLn in the conclusions

  • 99.
    Bonaccorsi, Manuele
    et al.
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Viale R. Piaggio, Pontedera, Italy.
    Fiorini, L
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Viale R. Piaggio, Pontedera, Italy.
    Sathyakeerthy, Subhash
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Cavallo, Filippo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Viale R. Piaggio, Pontedera, Italy.
    Dario, Paolo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Viale R. Piaggio, Pontedera, Italy.
    Design of cloud robotic services for senior citizens to improve independent living in multiple environments2015In: Intelligenza Artificiale, ISSN 1724-8035, Vol. 9, no 1, 63-72 p.Article in journal (Refereed)
    Abstract [en]

    The paper proposed a cloud robotic solution for the healthcare management of senior citizens, to demonstrate the opportunity to remotely provide continuous assistive robotic services to a number of seniors regardless to their position in the monitored environment. In particular, a medication reminding, a remote home monitoring and an user indoor localization service were outsourced in the cloud and provided to the robots, users and caregivers on request. The proposed system was composed of a number of robotic agents distributed over two smart environments: a flat at the Domocasa Lab (Peccioli, IT) and a condominium at the Angen site of the Orebro science park (Orebro, SE). The cloud acquired data from remote smart environments and enabled the local robots to provide advanced assistive services to a number of users. The proposed smart environments were able to collect raw data for the environmental monitoring and the localization of the users by means of wireless sensors, and provide such data to the cloud. On the cloud, specific algorithms improved the local robots, by providing event scheduling to accomplish assistive services and situation awareness on the users position and environments’ status. The indoor user localization service, was provided by means of commercial and ad-hoc sensors distributed over the environments and a sensor fusion algorithm on the cloud. The entire cloud solution was evaluated in terms of Quality of Service (QoS) to estimate the effectiveness of the architecture.

  • 100.
    Bonaccorsi, Manuele
    et al.
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Fiorini, Laura
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Cavallo, Filippo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Dario, Paolo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    A cloud robotics solution to improve social assistive robots for active and healthy aging2016In: International Journal of Social Robotics, ISSN 1875-4791, E-ISSN 1875-4805, Vol. 8, no 3, 393-408 p.Article in journal (Refereed)
    Abstract [en]

    Technological innovation in robotics and ICT represents an effective solution to tackle the challenge of providing social sustainable care services for the ageing population. The recent introduction of cloud technologies is opening new opportunities for the provisioning of advanced robotic services based on the cooperation of a number of connected robots, smart environments and devices improved by the huge cloud computational and storage capability. In this context, this paper aims to investigate and assess the potentialities of a cloud robotic system for the provisioning of assistive services for the promotion of active and healthy ageing. The system comprised two different smart environments, located in Italy and Sweden, where a service robot is connected to a cloud platform for the provisioning of localization based services to the users. The cloud robotic services were tested in the two realistic environments to assess the general feasibility of the solution and demonstrate the ability to provide assistive location based services in a multiple environment framework. The results confirmed the validity of the solution but also suggested a deeper investigation on the dependability of the communication technologies adopted in such kind of systems.

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