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  • 751.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Fuzzy logic in autonomous navigation2001In: Fuzzy logic techniques for autonomous vehicle navigation / [ed] Dimiter Driankov, Alessandro Saffiotti, Heidelberg: Physica Verlag, 2001, p. 3-24Chapter in book (Refereed)
    Abstract [en]

    The development of techniques for autonomous navigation constitutes one of the major trends in the current research on mobile robotics. In this case study, we discuss how fuzzy computation techniques have be used in the SRI International mobile robot Flakey to address some of the difficult issues posed by autonomous navigation: (i) how to design basic behaviors; (ii) how to coordinate behaviors to execute full navigation plans; and (iii) how to use approximate map information. Our techniques have been validated in both in-house experiments and public events. The use of fuzzy logic has resulted in smooth motion control, robust performance in face of errors in the prior knowledge and in the sensor data, and principled integration between different layers of control

  • 752.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Handling uncertainty in control of autonomous robots1999In: Artificial intelligence today: recent trends and developments / [ed] Michael J. Wooldridge, Manuela Veloso, Berlin: Springer Berlin/Heidelberg, 1999, Vol. 1600, p. 381-407Chapter in book (Refereed)
    Abstract [en]

    Autonomous robots need the ability to move purposefully and without human intervention in real-world environments that have not been specifically engineered for them. These environments are characterized by the pervasive presence of uncertainty: the need to cope with this uncertainty constitutes a major challenge for autonomous robots. In this note, we discuss this challenge, and present some specific solutions based on our experience on the use of fuzzy logic in mobile robots. We focus on three issues: how to realize robust motion control; how to flexibly execute navigation plans; and how to approximately estimate the robot's location.

  • 753.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    The Concept of Peis-Ecology: Integrating Robots in Smart Environments.2009In: Acta Futura, E-ISSN 2309-1940, no 3, p. 35-42Article in journal (Refereed)
    Abstract [en]

    The concept of Ecology of Physically Embedded Intelligent Systems, or PEIS-Ecology, combines insights from the fields of ubiquitous robotics and ambient intelligence to provide a new solution to building intelligent robots in the service of people. In this note I introduce this concept, summarize its main technological aspects, and speculate on its potential impact for space exploration.

  • 754.
    Saffiotti, Alessandro
    et al.
    Örebro University, School of Science and Technology.
    Broxvall, Mathias
    Örebro University, School of Science and Technology.
    Affordances in an ecology of physically embedded intelligent systems2008In: Towards affordance-based robot control, SPRINGER-VERLAG BERLIN, HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY , 2008, p. 106-121Conference paper (Refereed)
    Abstract [en]

    The concept of Ecology of Physically Embedded Intelligent Systems, or PFIS-Ecology, combines insights from the fields of autonomous robotics and ambient intelligence to provide a new solution to building intelligent robotic systems in the service of people. The concept of PEIS-Ecology also offers an interesting setting to study the applicability of Gibson's notion of affordances to an ecology of robots. In this paper we introduce this concept, and discuss its potential and implications both from an application point of view and from an ecological (Gibsonian) point of view. We also discuss some new scientific challenges introduced by a PEIS-Ecology, present our current steps toward its realization, and point at a few experimental results that show the viability of this concept.

  • 755.
    Saffiotti, Alessandro
    et al.
    Örebro University, School of Science and Technology.
    Broxvall, Mathias
    Örebro University, School of Science and Technology.
    Affordances in an ecology of physically embedded intelligent systems2008In: Towards affordance-based robot control / [ed] E. Rome, J. Hertzberg, G. Dorffner, Berlin: Springer , 2008, p. 106-121Chapter in book (Other academic)
    Abstract [en]

    The concept of Ecology of Physically Embedded Intelligent Systems, or PEIS-Ecology, combines insights fromthe fields of autonomous robotics and ambient intelligence to provide a new solution to building intelligent robotic systems in the service of people. The concept of PEIS- Ecology also offers an interesting setting to study the applicability of Gibson's notion of affordances to an ecology of robots. In this paper we introduce this concept, and discuss its potential and implications both from an application point of view and from an ecological (Gibsonian) point of view. We also discuss some new scientific challenges introduced by a Peis- Ecology, present our current steps toward its realization, and point at a few experimental results that show the viability of this concept.

  • 756.
    Saffiotti, Alessandro
    et al.
    Örebro University, Department of Technology.
    Broxvall, Mathias
    Örebro University, Department of Technology.
    PEIS ecologies: ambient intelligence meets autonomous robotics2005In: Proceedings of the 2005 joint conference on Smart objects and ambient intelligence: innovative context-aware services: usages and technologies, 2005, p. 275-280Conference paper (Refereed)
    Abstract [en]

    A common vision in the field of autonomous robotics is to create a skilled robot companion that is able to live in our homes and to perform physical tasks to help us in our everyday life. Another vision, coming from the field of ambient intelligence, is to create a network of intelligent devices that provides us with information, communication, and entertainment. We propose to combine these two visions into the new concept of an ecology of networked Physically Embedded Intelligent Systems (PEIS). In this paper, we define this concept, discuss ways to implement it, and illustrate it on a simple example involving some real robotic devices.

  • 757.
    Saffiotti, Alessandro
    et al.
    Örebro University, School of Science and Technology.
    Broxvall, Mathias
    Örebro University, School of Science and Technology.
    Gritti, Marco
    Örebro University, School of Science and Technology.
    LeBlanc, Kevin
    Örebro University, School of Science and Technology.
    Lundh, Robert
    Örebro University, School of Science and Technology.
    Rashid, Jayedur
    Örebro University, School of Science and Technology.
    Seo, Beom-Su
    Cho, Young-Jo
    The PEIS-ecology project: vision and results2008In: IEEE/RSJ international conference on intelligent robots and systems, IROS 2008, New York: IEEE , 2008, p. 2329-2335Conference paper (Refereed)
    Abstract [en]

    The vision of an Ecology of Physically Embedded Intelligent Systems, or PEIS-Ecology, combines insights from the fields of autonomous robotics and ambient intelligence to provide a new approach to building robotic systems in the service of people. In this paper, we present this vision, and we report the results of a four-year collaborative research project between Sweden and Korea aimed at the concrete realization of this vision. We focus in particular on three results: a robotic middleware able to cope with highly heterogeneous systems; a technique for autonomous self-configuration and re-configuration; and a study of the problem of sharing information of both physical and digital nature.

  • 758.
    Saffiotti, Alessandro
    et al.
    Örebro University, Department of Technology.
    Driankov, Dimiter
    Örebro University, Department of Technology.
    Duckett, Tom
    Örebro University, Department of Technology.
    A system for vision based human-robot interaction2004Conference paper (Refereed)
    Abstract [en]

    We describe our initial steps toward the realization of a robotic system for assisting fire-fighting and rescue services. The system implements the concept of shared autonomy between the robot and the human operator: the mobile robot performs local navigation, sensing and mapping, while the operator interprets the sensor data and provides strategic navigation goals.

  • 759.
    Saffiotti, Alessandro
    et al.
    Örebro University, Department of Technology.
    LeBlanc, Kevin
    Örebro University, Department of Technology.
    Active perceptual anchoring of robot behavior in a dynamic environment2000In: IEEE international conference on robotics and automation, ICRA '00: proceedings, 2000, p. 3796-3802Conference paper (Refereed)
    Abstract [en]

    Perceptual anchoring is the process of linking action to the appropriate objects in the environment via perception. The pivot of anchoring is the inclusion of micro-models of the world, or anchors, into a controller. In this paper, we propose to use anchors to focus the perceptual effort according to the current needs of the controller. We describe an active gaze control strategy able to maintain anchoring of several objects in a dynamic environment, and show how we have used it in a team of legged robots in the RoboCup'99 international robot soccer competition

  • 760.
    Saffiotti, Alessandro
    et al.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    SOFTEC: the Swedish open facility for technology in elder care2010Conference paper (Other academic)
  • 761.
    Saffiotti, Alessandro
    et al.
    Örebro University, Department of Technology.
    Ruspini, Enrique H.
    Global team coordination by local computation2001Conference paper (Refereed)
    Abstract [en]

    Desirability functions are an effective way to define group and individual objectives of a team of cooperating mobile robots. By combining desirability functions, we can identify the individual actions that best satisfy both sets of objectives. Combination, however, is global, posing high demands in terms of communication and computation resources. In this paper, we investigate a technique to perform this combination using local computations. Simulated experiments suggest that, under conditions of spatial locality, team control by local computation achieves the same performance than using a global technique

  • 762.
    Saffiotti, Alessandro
    et al.
    Örebro University, Department of Technology.
    Ruspini, Enrique H.
    Konolige, Kurt
    Using fuzzy logic for mobile robot control1999In: Practical applications of fuzzy technologies / [ed] Hans-Jürgen Zimmermann, Kluwer Academic, MA , 1999, p. 185-205Chapter in book (Other academic)
    Abstract [en]

    The development of techniques for autonomous operation in real-world, unstructured environments constitutes one of the major trends in the current research on mobile robotics. In spite of recent advances, a number of fundamental difficulties remain. In this chapter, we discuss how fuzzy logic techniques can be used to address some of these difficulties. To illustrate the discussion, we describe the fuzzy-logic solutions developed on Flakey, the mobile robot of SRI International

  • 763.
    Saffiotti, Alessandro
    et al.
    Örebro University, School of Science and Technology.
    van der Zant, Tijn
    CEO at RoboLect, CTO at SIM-CI, the Netherlands.
    The Impact of RoCKIn on Robotics2017In: RoCKIn: Benchmarking Through Robot Competitions / [ed] Pedro Lima, INTECH, 2017, p. 1-5Chapter in book (Refereed)
  • 764.
    Saffiotti, Alessandro
    et al.
    Örebro University, Department of Technology.
    Wasik, Zbigniew
    Örebro University, Department of Technology.
    Using hierarchical fuzzy behaviors in the RoboCup domain2003In: Autonomous robotic systems / [ed] Changjiu Zhou, Dario Maravall, Da Ruan, Janusz Kacprzyk, Heidelberg: Physica Verlag, 2003, Vol. 116, p. 235-262Chapter in book (Refereed)
    Abstract [en]

    An important reason for the popularity of the behavior-based paradigm in autonomous robotics is the possibility to design complex robot behaviors in an incremental way. We propose a fuzzy hierarchical behavior-based architecture, in which rules and meta-rules are used in a uniform way at all levels of the control hierarchy. This architecture has been successfully used in a number of robots performing autonomous navigation tasks. In this paper, we show the use of hierarchical fuzzy behaviors to implement a set of navigation and ball control behaviors for a Sony four-legged robot operating in the RoboCup domain. We also show that the logical structure of the rules and the hierarchical decomposition simplify the design of very complex behaviors, like the "GoalKeeper" behavior.

  • 765.
    Saffiotti, Alessandro
    et al.
    Örebro University, Department of Technology.
    Zumel, N. B.
    Ruspini, Enrique H.
    Multi-robot team coordination using desirabilities2000In: Proceedings of the 6th international conference on intelligent autonomous systems: IAS, 2000, p. 107-114Conference paper (Refereed)
    Abstract [en]

    Desirability functions are an effective way to express and implement complex behavior coordination strategies inside a single robot. In this paper, we extend the desirability function approach to deal with behaviors of teams of robots. We show that desirability functions offer a convenient tool to incorporate and blend individual objectives and team objectives. We illustrate our approach on two significant problems of team coordination: reactive formation motion control, and collaborative searching and tracking.

  • 766.
    Sahlin, Anders
    et al.
    Örebro University, School of Science and Technology.
    Särner, Erik
    Örebro University, School of Science and Technology.
    UTVECKLING AV SPEL I XNA TILL SWEDISH GAME AWARDS 20092009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report is centered on the development of a game with the goal to participate in the national game development competition for students, Swedish Game Awards 2009. Some of the things discussed are the theory behind, as well as the design and implementation of a two dimensional platform game created with XNA. The report also comments on the pitfalls and difficulties we encountered during the process of development. The reader is expected to have basic understanding of expressions and some knowledge concerning object oriented programming. We have tried to limit the use of technical terms in order to reach a wider audience.

  • 767.
    Sandahl, Thomas
    et al.
    Örebro University, School of Science and Technology.
    Reyes, Rafael
    Örebro University, School of Science and Technology.
    Mobilapplikation för Norrlandskontakten.se2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Smartphones have hit it big in the market recently and a need for websites to promote themselves on the market has also increased. The goal of this project is to enhance the dating site Norrlandskontakten.se’s role on the market. This is done by developing an application for the iPhone.

    This report describes the development of this application and the type of code design we chose to follow, in other words how the application is built and its functionality. Most of the work of developing this application has been about network communications and how this is linked to a web service. Given that this is an application based on the interaction between people with its primary goal to establish contact, it requires a lot of communication with the server.

    It has been important for the navigation and the use of the application to keep high availability and that the user is not tied down during load times. And at the same time keeping down the amount of data downloaded from the server down to reduce the load on its bandwidth.

    The project is made on behalf of the Company Sailsoft AB, which has developed Norrlandskontakten.se, the webpage this application is based on.

  • 768.
    Sandberg, Erik
    Örebro University, School of Science and Technology.
    Mjukvaruoptimering med fokus på prestanda och kodeffektivitet2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project is about analyzing and optimizing Generic Mobile’s messaging services with respect to performance (priority 1) and code efficiency (priority 2). The aim is to speed up the system so that a message will transit through as quickly as possible, while the load on software, hardware and database is minimal. To begin with, I will focus on optimizing the service "SMS via E-post" and then a more general approach to store-and-forward optimization will be discussed. Finally, an optimal method that works in similar systems is presented. 

    In order to demonstrate the effectiveness of the new system, a couple of analytical methods and how to analyze the data dynamically will be discussed.

  • 769.
    Sanfeliu, Alberto
    et al.
    Institut de Robòtica I Informàtica Industrial (UPC-CSIC), Universitat Politècnica de Catalunya, Barcelona, Spain.
    Hagita, Norihiro
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Network Robot Systems2008In: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 56, no 10, p. 793-797Article in journal (Refereed)
    Abstract [en]

     This article introduces the definition of Network Robot Systems (NRS) as is understood in Europe, USA and Japan. Moreover, it describes some of the NRS projects in Europe and Japan and presents a summary of the papers of this Special Issue.  

  • 770. Sanfeliu, Alberto
    et al.
    Hagita, Norihiro
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Special issue: Network robot systems2008In: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 56, no 10, p. 791-791Article in journal (Refereed)
  • 771.
    Sari, Anny Kartika
    et al.
    Department of Computer Science and Computer Engineering, La Trobe University, Victoria, Australia; Department of Computer Science and Electronics, Gadjah Mada University, Yogyakarta, Indonesia.
    Rahayu, J. Wenny
    Department of Computer Science and Computer Engineering, La Trobe University, Victoria, Australia.
    Bhatt, Mehul
    SFB/TR 8 Spatial Cognition, Informatics, University of Bremen, Bremen, Germany.
    An approach for sub-ontology evolution in a distributed health care enterprise2013In: Information Systems, ISSN 0306-4379, E-ISSN 1873-6076, Vol. 38, no 5, p. 727-744Article in journal (Refereed)
    Abstract [en]

    In response to the changing nature of health issues, standardized health ontologies such as SNOMED CT and UMLS incline to change more frequently than most other domain ontologies. Yet, semantic interoperability shared among institutions within a distributed health care enterprise relies heavily on the availability of a valid and up-to-date standardized ontology. In this paper, we propose the creation and preservation of sub-ontologies to deal with the frequent changes in health ontologies. Our approach focuses on the nature and characteristics of standard health ontologies, however it can also be applied to other domain ontologies with similar characteristics. Our sub-ontology evolution approach defines ways to create valid sub-ontologies for each specific health application, and to effectively develop a series of propagation mechanism when the main ontology changes. Our approach will (i) isolate the required change propagation to the relevant health applications that utilized the changing concepts only, and (ii) optimize the propagation mechanism to include the minimum number of operations only. Since a sub-ontology should be a valid ontology by itself, the change propagation approach used in this process should contain the rules to assure the validity of the produced sub-ontology while keeping the consistency of the sub-ontology to the evolved base ontology. A change identification process, which considers the nature of the health ontology change logs, is conducted to identify the semantics of the changes. From the evaluation, it is shown that the content of the evolved sub-ontologies produced using our approach is consistent to the evolved base ontology. Moreover, the propagation process can be performed more efficiently because the number of operations required for our change propagation method is lower than the number of operations required for direct re-extraction from the evolved base ontology.

  • 772.
    Sari, Anny Kartika
    et al.
    Department of Computer Science and Computer Engineering, La Trobe University, Victoria, Australia; Department of Computer Science and Electronics, Gadjah Mada University, Yogyakarta, Indonesi.
    Rahayu, J. Wenny
    Department of Computer Science and Computer Engineering, La Trobe University, Victoria, Australia.
    Bhatt, Mehul
    SFB/TR 8 Spatial Cognition, Informatics, University of Bremen, Bremen, Germany.
    Archetype sub-ontology: Improving constraint-based clinical knowledge model in electronic health records2012In: Knowledge-Based Systems, ISSN 0950-7051, E-ISSN 1872-7409, Vol. 26, p. 75-85Article in journal (Refereed)
    Abstract [en]

    The global effort in the standardization of electronic health records has driven the need for a model to allow medical practitioners to interact with the newly standardized medical information system by focusing on the actual medical concepts/processes rather than the underlying data representations. An archetype has been introduced as a model that represents functional health concepts or processes such as admission record, which enables capturing all information relevant to the processes transparently to the users. However, it is necessary to ensure that the archetypes capture accurately all information relevant to the archetype concepts. Therefore, a semantic backbone is required for each of the archetype.

    In this paper, we propose the development of an archetype sub-ontology for each archetype to represent the semantic content of the corresponding archetype. The sub-ontology is semi-automatically extracted from a standard health ontology, in this case SNOMED CT. Two steps performed to build an archetype sub-ontology are the annotation process and the extraction process, in which some rules have to be applied to maintain the validity of sub-ontology. The approach is evaluated by utilizing the archetype sub-ontologies produced in the development of a new archetype to ensure that only relevant archetypes can be linked to the archetype being developed, so that the only relevant data are captured using the particular archetype. It is shown that the method produces better results than the current approach in which an archetype sub-ontology is not used. We conclude that the archetype sub-ontology can represent well the semantic content of archetype.

  • 773.
    Scandurra, Isabella
    et al.
    Uppsala University.
    Holgersson, Jesper
    Skövde University.
    Lind, Thomas
    Uppsala University.
    Myreteg, Gunilla
    Uppsala University.
    Development of Patient Access to Electronic Health Records as a Step Towards Ubiquitous Public eHealth2013In: European Journal of ePractice, ISSN 1988-625X, E-ISSN 1988-625X, Vol. 20, p. 21-36Article in journal (Refereed)
  • 774.
    Scandurra, Isabella
    et al.
    APRI eHealth, Själevad, Sweden..
    Hägglund, Maria
    A collaborative design method to support integrated care.: An ICT development method containing continuous user validation improves the entire care process and the individual work situation2009In: International Journal of Integrated Care, ISSN 1568-4156, E-ISSN 1568-4156, Vol. 9, no Suppl.Article in journal (Refereed)
    Abstract [en]

    Introduction

    Integrated care involves different professionals, belonging to different care provider organizations and requires immediate and ubiquitous access to patient-oriented information, supporting an integrated view on the care process [1].

    Purpose

    To present a method for development of usable and work process-oriented information and communication technology (ICT) systems for integrated care.

    Theory and method

    Based on Human-computer Interaction Science and in particular Participatory Design [2], we present a new collaborative design method in the context of health information systems (HIS) development [3]. This method implies a thorough analysis of the entire interdisciplinary cooperative work and a transformation of the results into technical specifications, via user validated scenarios, prototypes and use cases, ultimately leading to the development of appropriate ICT for the variety of occurring work situations for different user groups, or professions, in integrated care.

    Results and conclusions

    Application of the method in homecare of the elderly resulted in an HIS that was well adapted to the intended user groups. Conducted in multi-disciplinary seminars, the method captured and validated user needs and system requirements for different professionals, work situations, and environments not only for current work; it also aimed to improve collaboration in future (ICT supported) work processes. A holistic view of the entire care process was obtained and supported through different views of the HIS for different user groups, resulting in improved work in the entire care process as well as for each collaborating profession.

  • 775.
    Scandurra, Isabella
    et al.
    Centre for eHealth, Uppsala University, Uppsala, Sweden .
    Hägglund, Maria
    Koch, Sabine
    Karolinska University.
    Application of the Multi-disciplinary Thematic Seminar Method in two Homecare Cases: A Comparative Study2008In: EHealth Beyond the Horizon – Get IT There: Proceedings of MIE2008 / [ed] Stig Kjær Andersen; Gunnar O. Klein; Stefan Schulz; Jos Aarts; M. Cristina Mazzoleni, Amsterdam: IOS Press, 2008, Vol. 136, p. 597-602Conference paper (Refereed)
    Abstract [en]

    A significant problem with current health information technologies is that they poorly support collaborative work of healthcare professionals, sometimes leading to a fragmentation of workflow and disruption of healthcare processes. Objective: This paper presents two homecare cases, both applying multi-disciplinary thematic seminars (MdTS) as a collaborative method for user needs elicitation and requirements specification. Methods: This study describes the MdTS application to elicit user needs from different perspectives to coincide with collaborative professions' work practices in two cases. Results: Despite different objectives, the two cases validated that MdTS emphasized the "points of intersection" in cooperative work. Different user groups with similar, yet distinct needs reached a common understanding of the entire work process, agreed upon requirements and participated in the design of prototypes supporting cooperative work. Conclusion: MdTS was applicable in both exploratory and normative studies aiming to elicit the specific requirements in a cooperative environment.

  • 776.
    Scandurra, Isabella
    et al.
    Centre for eHealth, Uppsala University, University Hospital, Uppsala, Sweden.
    Hägglund, Maria
    Koch, Sabine
    Karolinska University.
    From user needs to system specifications: Multi-disciplinary thematic seminars as a collaborative design method for development of health information systems2008In: Journal of Biomedical Informatics, ISSN 1532-0464, E-ISSN 1532-0480, Vol. 41, no 4, p. 557-569Article in journal (Refereed)
    Abstract [en]

    This paper presents a new multi-disciplinary method for user needs analysis and requirements specification in the context of health information systems based on established theories from the fields of participatory design and computer supported cooperative work (CSCW). Whereas conventional methods imply a separate, sequential needs analysis for each profession, the “multi-disciplinary thematic seminar” (MdTS) method uses a collaborative design process. Application of the method in elderly homecare resulted in prototypes that were well adapted to the intended user groups. Vital information in the points of intersection between different care professions was elicited and a holistic view of the entire care process was obtained. Health informatics-usability specialists and clinical domain experts are necessary to apply the method. Although user needs acquisition can be time-consuming, MdTS was perceived to efficiently identify in-context user needs, and transformed these directly into requirements specifications. Consequently the method was perceived to expedite the entire ICT implementation process.

  • 777.
    Scandurra, Isabella
    et al.
    Centre for eHealth, Uppsala University, Uppsala, Sweden.
    Hägglund, Maria
    Koch, Sabine
    Karolinska University.
    Usability Laboratory Test of a Novel Mobile Healthcare Application with Experienced Home Help Service Staff2008In: Open Medical Informatics Journal, ISSN 1874-4311, Vol. 2, p. 117-128Article in journal (Refereed)
    Abstract [en]

    Using participatory design, we developed and deployed a mobile Virtual Health Record (VHR) on a personal digital assistant (PDA) together with experienced homecare staff. To assess transferability to a second setting and usability when used by novice users with limited system education the application was tested in a usability lab. Eight participants from another homecare district performed tasks related to daily homecare work using the VHR. Test protocols were analyzed with regard to effectiveness, potential usability problems and user satisfaction. Usability problems having impact on system performance and contextual factors affecting system transferability were uncovered. Questionnaires revealed that the participants frequently used computers, but never PDAs. Surprisingly there were only minor differences in input efficiency between novice and experienced users. The participants were overall satisfied with the application. However, transfer to another district can not be performed, unless by means of careful field observations of contextual differences.

  • 778.
    Scandurra, Isabella
    et al.
    Uppsala universitet, Institutionen för medicinska vetenskaper, Uppsala, Sweden.
    Hägglund, Maria
    Uppsala universitet, Institutionen för medicinska vetenskaper, Uppsala, Sweden.
    Moström, Dennis
    Koch, Sabine
    Uppsala universitet, Institutionen för medicinska vetenskaper, Uppsala, Sweden.
    Old@Home: Tekniskt stöd till mobil närvård2004In: Proceedings of Sundsvall 42: ADB i verksamhetens tjänst, 2004, p. 108-110Conference paper (Other academic)
  • 779.
    Scandurra, Isabella
    et al.
    Centre for eHealth, Uppsala University, Sweden.
    Moström, Dennis
    Hägglund, Maria
    Introducing a Mobile ICT system in Homecare: Evaluation of a Socio-technical Implementation Process 2008In: Journal on Information Technology in Healthcare, ISSN 1479-649X, Vol. 6, no 5, p. 356-366Article in journal (Refereed)
  • 780.
    Scandurra, Isabella
    et al.
    Division of Visual Information and Interaction, Department of Information Technology, Uppsala University, Uppsala, Sweden.
    Sjölinder, Marie
    Swedish ICT/SICS.
    Participatory design with seniors: Design of future services and iterative refinements of interactive eHealth Services for old citizens2013In: Medicine 2.0, ISSN 1923-2195Article in journal (Refereed)
    Abstract [en]

    Background: There is an increasing social isolation among the elderly today. This will be an even larger issue in the future with growing numbers of elderly and less resources, for example, in terms of economy and staff. Loneliness and social isolation can, however, be addressed in several ways using different interactive eHealth services.

    Objective: This case study investigated novel eHealth services for the elderly, and their usage of a social interactive device designed especially for them.

    Methods: In this work, we used an innovative mobile communication device connected to the television (TV), which worked as a remotely controlled large interactive screen. The device was tested by 8 volunteers who visited a senior center. They were between 65 and 80 years of age and lived in their own homes. Throughout the 1.5 year-long project, 7 design workshops were held with the seniors and the staff at the center. During these workshops, demands and preferences regarding existing and new services were gathered. At the end of the project the participants’ experience of the device and of the services was elaborated in 3 workshops to get ideas for improved or new meaningful services. During the data analyses and development process, what seniors thought would be useful in relation to what was feasible was prioritized by the development company.

    Results: Regarding daily usage, the seniors reported that they mainly used the service for receiving information from the senior center and for communication with other participants in the group or with younger relatives. They also read information about events at the senior center and they liked to perform a weekly sent out workout exercise. Further, they played games such as Memory and Sudoku using the device. The service development focused on three categories of services: cognitive activities, social activities, and physical activities. A cognitive activity service that would be meaningful to develop was a game for practicing working memory. In the social activities category, the seniors wanted different quizzes and multi-player games. For physical activities, the seniors desired more workout exercises and suggestions for guided walking routes. A new category, “information and news”, was suggested since they lacked services like senior-customized global and local news.

    Conclusions: This study showed the importance of input from a group of seniors when designing new services for elderly citizens. Besides input to interactive eHealth service development for seniors, this study showed the importance of a social context around such work. The seniors were very engaged throughout the project and workshops were frequently visited and the seniors became friends. The high amount of input from the seniors could be explained in terms of social inclusion; they belonged to a group and each member was considered important for the work. The friendly workshop atmosphere facilitated new ideas and redesign of the services.

  • 781.
    Schabert, Antek
    Örebro University, School of Science and Technology.
    Integrating the use of prior information into Graph-SLAM with NDTregistration for loop detection2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 782.
    Schattenberg, Bernd
    et al.
    Universität Ulm, Ulm, Germany.
    Bidot, Julien
    Universität Ulm, Ulm, Germany.
    Biundo, Susanne
    Universität Ulm, Ulm, Germany.
    On the construction and evaluation of flexible plan-refinement strategies2007In: KI 2007: advances in artificial intelligence / [ed] Joachim Hertzberg, Michael Beetz, Roman Englert, 2007, p. 367-381Conference paper (Refereed)
    Abstract [en]

    This paper describes a system for the systematic construction and evaluation of planning strategies. It is based on a proper formal account of refinement planning and allows us to decouple plan-deficiency detection, refinement computation, and search control. In adopting this methodology, planning strategies can be explicitly described and easily deployed in various system configurations.

    We introduce novel domain-independent planning strategies that are applicable to a wide range of planning capabilities and methods. These so-called HotSpot strategies are guided by information about current plan defects and solution options. The results of a first empirical performance evaluation are presented in the context of hybrid planning.

  • 783.
    Schattenberg, Bernd
    et al.
    Universität Ulm, Ulm, Germany.
    Bidot, Julien
    Universität Ulm, Ulm, Germany.
    Geßler, Sascha
    Universität Ulm, Ulm, Germany.
    Biundo, Susanne
    Universität Ulm, Ulm, Germany.
    A framework for interactive hybrid planning2009In: KI 2009: advances in artificial intelligence / [ed] Bärbel Mertsching, Marcus Hund, Zaheer Aziz, Springer, 2009, p. 17-24Conference paper (Refereed)
    Abstract [en]

    Hybrid planning provides a powerful mechanism to solve real-world planning problems. We present a domain-independent, mixed-initiative approach to plan generation that is based on a formal concept of hybrid planning. It allows any interaction modalities and models of initiative while preserving the soundness of the planning process. Adequately involving the decision competences of end-users in this way will improve the application potential as well as the acceptance of the technology.

  • 784.
    Schougaard, Daniel
    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.
    Evaluation of Professional Cloud Password Management Tools2016In: Current Trends in Web Engineering: ICWE 2016 International Workshops, 2016, p. 16-28Conference paper (Refereed)
    Abstract [en]

    Strong passwords have been preached since decades. However, lot of the regular users of IT systems resort to simple and repetitive passwords, especially nowadays in the "service era". To help alleviate this problem, a new class of software grew popular: password managers. Since their introduction, password managers have slowly been migrating into the cloud. In this paper we review and analyze current professional password managers in the cloud. We discuss several functional and nonfunctional requirements to evaluate existing solutions and we sum up their strengths and weaknesses. The main conclusion is that a silver bullet solution is not available yet and that this type of tools still deserve a significant research effort from the privacy and security community.

  • 785.
    Schultz, Carl
    et al.
    University of Münster, Münster, Germany; The DesignSpace Group, Bremen, Germany.
    Bhatt, Mehul
    University of Bremen, Bremen, Germany; The DesignSpace Group, Bremen, Germany.
    A Numerical Optimisation Based Characterisation of Spatial Reasoning2016In: Rule Technologies. Research, Tools, and Applications: 10th International Symposium, RuleML 2016, Stony Brook, NY, USA, July 6-9, 2016. Proceedings / [ed] Jose Julio Alferes, Leopoldo Bertossi, Guido Governatori, Paul Fodor, Dumitru Roman, Springer, 2016, p. 199-207Conference paper (Refereed)
    Abstract [en]

    We present a novel numerical optimisation based characterisation of spatial reasoning in the context of constraint logic programming (CLP). The approach —formalised and implemented within CLP— is developed as an extension to CLP(QS), a declarative spatial reasoning framework providing a range of mixed quantitative-qualitative spatial representation and reasoning capabilities. We demonstrate the manner in which the numerical optimisation based extensions further enhance the declarative spatial reasoning capabilities of CLP(QS).

  • 786.
    Schultz, Carl
    et al.
    The Design Space Group, Germany; University of Münster, Germany.
    Bhatt, Mehul
    The Design Space Group, Germany; University of Bremen, Germany.
    Constructive Geometric Constraint Solving as a General Framework for KR-Based Declarative Spatial Reasoning2016In: Declarative Learning Based Programming: Technical Report WS-16-07, AI Access Foundation , 2016, p. 417-423Conference paper (Refereed)
    Abstract [en]

    We present a robust and scalable KR-centered foundation for modularly supporting general declarative spatial representation and reasoning within diverse declarative programming AI frameworks. Based on Constructive Geometric Constraint Solving, our approach provides the foundations for mixed qualitative-quantitative reasoning about space - mereotopology, relative orientation, size, proximity - encompassing key application-driven capabilities such as qualification, spatial consistency solving, quantification, and dynamic geometry. The paper also demonstrates: (a) the framework with benchmark problems (e.g., contact and orientation problems) and applications in spatial Q/A; (b) integration with constraint logic programming, and (c) empirical results illustrating how the proposed encodings outperform existing methods by orders of magnitude on the selected problems.

  • 787.
    Schultz, Carl
    et al.
    The DesignSpace Group, Germany; Spatial Intelligence Lab (SIL), University of Münster, Germany.
    Bhatt, Mehul
    The DesignSpace Group, Germany; Department of Computer Science, University of Bremen, Germany.
    Borrmann, André
    Chair of Computational Modeling and Simulation, Technische Universität München, Germany.
    Bridging qualitative spatial constraints and feature-based parametric modelling: Expressing visibility and movement constraints2017In: Advanced Engineering Informatics, ISSN 1474-0346, E-ISSN 1873-5320, Vol. 31, p. 2-17Article in journal (Refereed)
    Abstract [en]

    We present a concept for integrating state-of-the-art methods in geometric and qualitative spatial representation and reasoning with feature-based parametric modelling systems. Using a case-study involving a combination of topological, visibility, and movement constraints, we demonstrate the manner in which a parametric model may be constrained by the spatial aspects of conceptual design specifications and higher-level semantic design requirements. We demonstrate the proposed methodology by applying it to architectural floor plan layout design, where a number of spaces with well defined functionalities have to be arranged such that particular functional design constraints are maintained. The case-study is developed by an integration of the declarative spatial reasoning system CLP(QS) (CLP(QS) - a declarative spatial reasoning system. www.spatial-reasoning.com.) with the parametric CAD system FreeCAD.

  • 788.
    Schultz, Carl
    et al.
    University of Münster, Münster, Germany; The DesignSpace Group, Bremen, Germany.
    Bhatt, Mehul
    University of Bremen, Bremen, Germany; The DesignSpace Group, Bremen, Germany.
    Suchan, Jakob
    University of Bremen, Bremen, Germany; The DesignSpace Group, Bremen, Germany.
    Probabilistic Spatial Reasoning in Constraint Logic Programming2016In: Scalable Uncertainty Management: 10th International Conference, SUM 2016, Nice, France, September 21-23, 2016, Proceedings / [ed] Steven Schockaert, Pierre Senellart, Springer, 2016, p. 289-302Conference paper (Refereed)
    Abstract [en]

    In this paper we present a novel framework and full implementation of probabilistic spatial reasoning within a Logic Programming context. The crux of our approach is extending Probabilistic Logic Programming (based on distribution semantics) to support reasoning over spatial variables via Constraint Logic Programming. Spatial reasoning is formulated as a numerical optimisation problem, and we implement our approach within ProbLog 1. We demonstrate a range of powerful features beyond what is currently provided by existing probabilistic and spatial reasoning tools.

  • 789.
    Schultz, Carl P. L.
    et al.
    SFB/TR 8 Spatial Cognition, University of Bremen, Bremen, Germany.
    Bhatt, Mehul
    SFB/TR 8 Spatial Cognition, University of Bremen, Bremen, Germany.
    A multi-modal data access framework for spatial assistance systems: Use-cases with the industry foundation classes (IFC)2010In: Proceedings of the 2nd ACM SIGSPATIAL International Workshop on Indoor Spatial Awareness: ISA 2010, Association for Computing Machinery (ACM), 2010, p. 39-46Conference paper (Refereed)
    Abstract [en]

    Spatial assistance systems are computational embodiments of spatial decision-making and other forms of analytical abilities that otherwise typically require extensive domain-specific training, knowledge, and expertise. Broadly, such systems are essentially instruments of assistance, assurance and empowerment. Whereas these systems may vary in the domain of application and the precise manner of intelligent assistance, there exist several fundamental similarities from a systemic and information-theoretic viewpoint with regard to the ontological and computational foundations that underlie their practical design and implementation.

    We present a multi-modal spatial data access framework designed to serve the informational and computational requirements of the class of spatial assistance systems that are intended to provide intelligent spatial decision-making capabilities. The framework focuses on multi-perspective semantics, qualitative and artefactual abstractions, and industrial conformance and interoperability. We position the framework, and also provide use-cases with distinct application domains.

  • 790.
    Schultz, Carl P. L.
    et al.
    Cognitive Systems (CoSy) University of Bremen, Bremen, Germany.
    Bhatt, Mehul
    Cognitive Systems (CoSy) University of Bremen, Bremen, Germany.
    Declarative Computing with Shapes and Shadows2013In: SHAPES 2013: Proceedings of the Second Interdisciplinary Workshop The Shape of Things, Rio de Janeiro, Brazil, April 3-4, 2013, CEUR Workshop Proceedings , 2013, Vol. 1007, p. 143-150Conference paper (Refereed)
    Abstract [en]

    We present a preliminary concept and a prototypical implementation of a declarative computing framework that is capable of reasoning about 3D physical entities, and the shadows that they cast in open or uniformly lit environments. For this paper, we restrict our scope of 'uniform lighting' to sunlight, and its incidence on a given geospatially and temporally referenced location. The model extends traditional techniques from computational geometry and computer graphics that are primarily motivated by simulation or visualisation. In particular, our declarative framework is capable of deriving and reasoning about the objects and their cast shadows in a knowledge processing sense, e.g., involving qualitative abstraction and semantic specification of requirements, query capability, ensuring conceptual consistency of design requirements. Our ontology of objects and shadows, and the resulting computational framework serves as a foundational engine for high-level conceptual (spatial) design assistance technology. The capabilities demonstrated in this paper are aimed at applications in spatial design, chiefly encompassing Computer-Aided Architecture Design (CAAD), Urban Planning, and Interior Design.

  • 791.
    Schultz, Carl P. L.
    et al.
    Spatial Cognition Research Center (SFB/TR 8), University of Bremen, Bremen, Germany.
    Bhatt, Mehul
    Spatial Cognition Research Center (SFB/TR 8), University of Bremen, Bremen, Germany.
    Declarative Spatial Reasoning with Boolean Combinations of Axis-Aligned Rectangular Polytopes2014In: ECAI 2014: 21st European Conference on Artificial Intelligence, 18-22 August 2014, Prague, Czech Republic - Including Prestigious Applications of Intelligent Systems (PAIS 2014). Proceedings / [ed] Torsten Schaub, Gerhard Friedrich, Barry O'Sullivan, IOS Press , 2014, Vol. 263, p. 795-800Conference paper (Refereed)
    Abstract [en]

    We present a formal framework and implementation for declarative spatial representation and reasoning about the topological relationships between boolean combinations of regions (i.e., union, intersection, difference, xor). Regions of space here correspond to arbitrary axis aligned n-polytope objects, with geometric parameters either fully grounded, partially grounded, or completely unspecified. The framework is implemented in the context of CLP(QS)(2), a constraint logic programming based declarative spatial reasoning system providing support for geometric and qualitative spatial abstraction and inference capabilities.

    We demonstrate that our method can solve packing, contact, containment, and constructive proof problems that are unsolvable using standard relational algebraic approaches for qualitative spatial reasoning (QSR). Our approach is driven by general accessibility of spatial reasoning via KR languages for their application in domains such as design, geography, robotics, and cognitive vision.

  • 792.
    Schultz, Carl P. L.
    et al.
    Spatial Cognition Research Center (SFB / TR 8) and Cognitive Systems (CoSy), University of Bremen, Bremen, Germany.
    Bhatt, Mehul
    Spatial Cognition Research Center (SFB / TR 8) and Cognitive Systems (CoSy), University of Bremen, Bremen, Germany.
    InSpace3D: A Middleware for Built Environment Data Access and Analytics2013In: International Conference on Computational Science, ICCS 2013, Elsevier , 2013, Vol. 18, p. 80-89Conference paper (Refereed)
    Abstract [en]

    Standardisation, archiving, and digital access of spatial data pertaining to built-up environments is an area acquiring increasing attention amongst several interest groups: policy makers, designers and planners, civil engineers, infrastructure management and public service personnel, building users. Initiatives such as the Building Information Model (BIM), Industry Foundation Classes (IFC), and CityGML are creating the information-theoretic backbone that guides the crucial aspects of quality, exchange, and interoperability of spatial data at the environmental and urban scale. However, due to the inherent scale, complexity, and detailed geometric character of building information data, extracting useful semantic and qualitative knowledge for accomplishing high-level analytical tasks is still an extremely complex and error prone process involving data intensive computing. We propose a uniform spatial data access middleware that can provide a combination of high-level, multi-modal, semantic, and quantitative-qualitative spatial data access and analytical capability. We present the core computational capabilities for the proposed middleware and present an overview of the high-level spatial model and its compliance with the industry standard IFC. A key theoretical contribution is a framework for investigating the computational complexity of deriving spatial artefacts within the context of building informatics. Additionally, we empirically investigate the feasibility and practicality of the derivation of spatial artefacts by conducting experiments on seven industry-scale IFC models. The experiment results show that, despite having non-linear polynomial increase with respect to time, deriving spatial artefacts is practical with large designs.

  • 793.
    Schultz, Carl P. L.
    et al.
    Project [DesignSpace], University of Bremen, Bremen, Germany.
    Bhatt, Mehul
    Project [DesignSpace], University of Bremen, Bremen, Germany.
    Multimodal spatial data access for architecture design assistance2012In: Artificial intelligence for engineering design, analysis and manufacturing, ISSN 0890-0604, E-ISSN 1469-1760, Vol. 26, no 2, p. 177-203Article in journal (Refereed)
    Abstract [en]

    We present a multimodal spatial data access framework designed to serve the informational and computational requirements of architectural design assistance systems that are intended to provide intelligent spatial decision support and analytical capabilities. The framework focuses on multiperspective semantics, qualitative and artifactual spatial abstractions, and industrial conformance and interoperability within the context of the industry foundation classes. The framework provides qualitative and cognitively adequate representational mechanisms, and the formal interpretation of the structural form of indoor spaces that are not directly provided by conventional computer-aided design based or quantitative models of space. We illustrate the manner in which these representations directly provide the spatial abstractions that are needed to enable the implementation of intelligent analytical capabilities in design assistance tools. We introduce the framework, and also provide detailed use cases that illustrate the usability of the framework and the manner of its utilization within architectural design assistance systems.

  • 794.
    Schultz, Carl P. L.
    et al.
    Institute for Geoinformatics, University of Münster, Münster, Germany; The DesignSpace Group, Bremen, Germany.
    Bhatt, Mehul
    Department of Computer Science, University of Bremen, Bremen, Germany; The DesignSpace Group, Bremen, Germany.
    Spatial Symmetry Driven Pruning Strategies for Efficient Declarative Spatial Reasoning2015In: Spatial Information Theory: 12th International Conference, COSIT 2015, Santa Fe, NM, USA, October 12-16, 2015, Proceedings / [ed] Sara Irina Fabrikant, Martin Raubal, Michela Bertolotto, Clare Davies, Scott Freundschuh, Scott Bell, Springer , 2015, Vol. 9368, p. 331-353Conference paper (Refereed)
    Abstract [en]

    Declarative spatial reasoning denotes the ability to (declaratively) specify and solve real-world problems related to geometric and qualitative spatial representation and reasoning within standard knowledge representation and reasoning (KR) based methods (e. g., logic programming and derivatives). One approach for encoding the semantics of spatial relations within a declarative programming framework is by systems of polynomial constraints. However, solving such constraints is computationally intractable in general (i. e. the theory of real-closed fields).

    We present a new algorithm, implemented within the declarative spatial reasoning system CLP(QS), that drastically improves the performance of deciding the consistency of spatial constraint graphs over conventional polynomial encodings. We develop pruning strategies founded on spatial symmetries that form equivalence classes (based on affine transformations) at the qualitative spatial level. Moreover, pruning strategies are themselves formalised as knowledge about the properties of space and spatial symmetries. We evaluate our algorithm using a range of benchmarks in the class of contact problems, and proofs in mereology and geometry. The empirical results show that CLP(QS) with knowledge-based spatial pruning outperforms conventional polynomial encodings by orders of magnitude, and can thus be applied to problems that are otherwise unsolvable in practice.

  • 795.
    Schultz, Carl P. L.
    et al.
    University of Bremen, Bremen, Germany.
    Bhatt, Mehul
    University of Bremen, Bremen, Germany.
    Towards a Declarative Spatial Reasoning System2012In: ECAI 2012: 20th European Conference on Artificial Intelligence, 27-31 August 2012, Montpellieer, France : including Prestigious Applications of Artificial Intelligence (PAIS-2010) systems demonstrations track : proceedings / [ed] Luc De Raedt, Christian Bessiere, Didier Dubois, Patrick Doherty, Paolo Frasconi, Fredrik Heintz, Peter Lucas, IOS Press , 2012, Vol. 242, p. 925-926Conference paper (Refereed)
    Abstract [en]

    We present early results on the development of a declarative spatial reasoning system within the context of the Constraint Logic Programming (CLP) framework. The system is capable of modelling and reasoning about qualitative spatial relations pertaining to multiple spatial domains, i.e., one or more aspects of space such as topology, and intrinsic and extrinsic orientation. It provides a seamless mechanism for combining formal qualitative spatial calculi within one framework, and provides a Prolog-based declarative interface for AI applications to abstract and reason about quantitative, geometric information in a qualitative manner. Based on previous work concerning the formalisation of the framework [ 2], we present ongoing work to develop the theoretical result into a comprehensive reasoning system (and Prolog-based library) which may be used independently, or as a logic-based module within hybrid intelligent systems.

  • 796.
    Schwaneberg, Oliver
    et al.
    Bonn-Rhein-Sieg University of Applied Sciences, St. Augustin, Germany.
    Köckemann, Uwe
    Bonn-Rhein-Sieg University of Applied Sciences, St. Augustin, Germany.
    Steiner, Holger
    Bonn-Rhein-Sieg University of Applied Sciences, St. Augustin, Germany.
    Sporrer, S.
    onn-Rhein-Sieg University of Applied Sciences, St. Augustin, Germany.
    Kolb, Andreas
    University of Siegen, Siegen, Germany.
    Jung, Norbert
    onn-Rhein-Sieg University of Applied Sciences, St. Augustin, Germany.
    Material classification through distance aware multispectral data fusion2013In: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 24, no 4, article id 045001Article in journal (Refereed)
    Abstract [en]

    Safety applications require fast, precise and highly reliable sensors at low costs. This paperpresents signal processing methods for an active multispectral optical point sensorinstrumentation for which a first technical implementation exists. Due to the very demandingrequirements for safeguarding equipment, these processing methods are targeted to run on asmall embedded system with a guaranteed reaction time T < 2 ms and a sufficiently lowfailure rate according to applicable safety standards, e.g., ISO-13849. The proposed dataprocessing concept includes a novel technique for distance-aided fusion of multispectral datain order to compensate for displacement-related alteration of the measured signal. Thedistance measuring is based on triangulation with precise results even for low-resolutiondetectors, thus strengthening the practical applicability. Furthermore, standard components,such as support vector machines (SVMs), are used for reliable material classification. Allmethods have been evaluated for variants of the underlying sensor principle. Therefore, theresults of the evaluation are independent of any specific hardware.

  • 797.
    Shahid, Zahraa
    Örebro University, School of Science and Technology.
    Design and development of intelligentapartments2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Developments in the elds of Ambient Intelligent Environments (AmIE) and UbiquitousComputing environments have provided the opportunity to develop assistive technologiesto help individuals who need medical care on a daily basis; in fact the integration betweenrobots, smart actuators and sensors can ease the execution of several domestic tasks.Since building a real physical IE is costly, simulations have opened the door to variouspossibilities to design, test and explore dierent scenarios of virtual IE. This thesisproject is aimed at developing an agile prototyping toolkit that provides the means forusers to simulate smart environments for robotics, AmIE and Ubiquitous Computingelds. This toolkit leverages well known software middlewares: Robot Operating System(ROS) and Gazebo. The former is a middleware providing access to several state of theart techniques used in robotics as well as to a variety of hardware platforms. The latterprovides a simulator which allows to reproduce 3D environments as well as roboticplatforms. Besides reproducing realistic scenarios, the proposed framework easily allowsto go beyond a single apartment: in particular in this thesis a double oor building hasbeen taken into account. Performances about this scenario and the integration withexisting middlewares are also provided.

  • 798.
    Shi, Min
    et al.
    Department of Computer and Information Science, Norwegian University of Science and Technology, Trondheim, Norway.
    Gao, Shang
    Örebro University, Örebro University School of Business. Department of Informatics.
    Reference sharing: a new collaboration model for cooperative coevolution2017In: Journal of Heuristics, ISSN 1381-1231, E-ISSN 1572-9397, Vol. 23, no 1, p. 1-30Article in journal (Refereed)
    Abstract [en]

    Cooperative coevolutionary algorithms have been a popular and effective learning approach to solve optimization problems through problem decomposition. However, their performance is highly sensitive to the degree of problem separability. Different collaboration mechanisms usually have to be chosen for particular problems. In the paper, we aim to design a collaboration model that can be successfully applied to a wide range of problems. We present a novel collaboration mechanism that offers this type of potential, along with a new sorting strategy for individuals that are assigned multiple fitness values. Furthermore, we demonstrate and analyze our algorithm through comparison studies with other popular cooperative coevolutionary models on a suite of standard function optimization problems.

  • 799.
    Siddiqui, Abujawad Rafid
    Blekinge Tekniska Högskola, Institutionen för kommunikationssystem.
    On Fundamental Elements of Visual Navigation Systems2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Visual navigation is a ubiquitous yet complex task which is performed by many species for the purpose of survival. Although visual navigation is actively being studied within the robotics community, the determination of elemental constituents of a robust visual navigation system remains a challenge. Motion estimation is mistakenly considered as the sole ingredient to make a robust autonomous visual navigation system and therefore efforts are made to improve the accuracy of motion estimations. On the contrary, there are other factors which are as important as motion and whose absence could result in inability to perform seamless visual navigation such as the one exhibited by humans. Therefore, it is needed that a general model for a visual navigation system be devised which would describe it in terms of a set of elemental units. In this regard, a set of visual navigation elements (i.e. spatial memory, motion memory, scene geometry, context and scene semantics) are suggested as building blocks of a visual navigation system in this thesis. A set of methods are proposed which investigate the existence and role of visual navigation elements in a visual navigation system. A quantitative research methodology in the form of a series of systematic experiments is conducted on these methods. The thesis formulates, implements and analyzes the proposed methods in the context of visual navigation elements which are arranged into three major groupings; a) Spatial memory b) Motion Memory c) Manhattan, context and scene semantics. The investigations are carried out on multiple image datasets obtained by robot mounted cameras (2D/3D) moving in different environments.

    Spatial memory is investigated by evaluation of proposed place recognition methods. The recognized places and inter-place associations are then used to represent a visited set of places in the form of a topological map. Such a representation of places and their spatial associations models the concept of spatial memory. It resembles the humans’ ability of place representation and mapping for large environments (e.g. cities). Motion memory in a visual navigation system is analyzed by a thorough investigation of various motion estimation methods. This leads to proposals of direct motion estimation methods which compute accurate motion estimates by basing the estimation process on dominant surfaces. In everyday world, planar surfaces, especially the ground planes, are ubiquitous. Therefore, motion models are built upon this constraint.

    Manhattan structure provides geometrical cues which are helpful in solving navigation problems. There are some unique geometric primitives (e.g. planes) which make up an indoor environment. Therefore, a plane detection method is proposed as a result of investigations performed on scene structure. The method uses supervised learning to successfully classify the segmented clusters in 3D point-cloud datasets. In addition to geometry, the context of a scene also plays an important role in robustness of a visual navigation system. The context in which navigation is being performed imposes a set of constraints on objects and sections of the scene. The enforcement of such constraints enables the observer to robustly segment the scene and to classify various objects in the scene. A contextually aware scene segmentation method is proposed which classifies the image of a scene into a set of geometric classes. The geometric classes are sufficient for most of the navigation tasks. However, in order to facilitate the cognitive visual decision making process, the scene ought to be semantically segmented. The semantic of indoor scenes as well as semantic of the outdoor scenes are dealt with separately and separate methods are proposed for visual mapping of environments belonging to each type. An indoor scene consists of a corridor structure which is modeled as a cubic space in order to build a map of the environment. A “flash-n-extend” strategy is proposed which is responsible for controlling the map update frequency. The semantics of the outdoor scenes is also investigated and a scene classification method is proposed. The method employs a Markov Random Field (MRF) based classification framework which generates a set of semantic maps.

    List of papers
    1. Multi-Cue Based Place Learning for Mobile Robot Navigation
    Open this publication in new window or tab >>Multi-Cue Based Place Learning for Mobile Robot Navigation
    2012 (English)In: Autonomous and Intelligent Systems: Proceedings / [ed] Mohamed Kamel, Fakhri Karray, Hani Hagras, Springer , 2012, p. 50-58Conference paper, Published paper (Refereed)
    Abstract [en]

    Place recognition is important navigation ability for autonomous navigation of mobile robots. Visual cues extracted from images provide a way to represent and recognize visited places. In this article, a multi-cue based place learning algorithm is proposed. The algorithm has been evaluated on a localization image database containing different variations of scenes under different weather conditions taken by moving the robot-mounted camera in an indoor-environment. The results suggest that joining the features obtained from different cues provide better representation than using a single feature cue.

    Place, publisher, year, edition, pages
    Springer, 2012
    Series
    Lecture notes in computer science, ISSN 0302-9743 ; 7326 LNAI
    Keyword
    place learning, visual cues, place recognition, robot navigation, localization.
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-46480 (URN)10.1007/978-3-642-31368-4_7 (DOI)2-s2.0-84864124357 (Scopus ID)978-3-642-31367-7 (ISBN)978-3-642-31368-4 (ISBN)
    Conference
    3rd International Conference on Autonomous and Intelligent Systems, AIS 2012, Aveiro, Portugal, June 25-27, 2012
    Available from: 2012-12-03 Created: 2015-11-12 Last updated: 2018-01-10Bibliographically approved
    2. Robust Place Recognition with an Application to Semantic Topological Mapping
    Open this publication in new window or tab >>Robust Place Recognition with an Application to Semantic Topological Mapping
    2013 (English)In: Sixth International Conference on Machine Vision (ICMV 2013) / [ed] Branislav Vuksanovic; Jianhong Zhou; Antanas Verikas, SPIE - International Society for Optical Engineering, 2013Conference paper, Published paper (Refereed)
    Abstract [en]

    The problem of robust and invariant representation of places is being addressed. A place recognition technique is proposed followed by an application to a semantic topological mapping. The proposed technique is evaluated on a robot localization database which consists of a large set of images taken under various weather conditions. The results show that the proposed method can robustly recognize the places and is invariant to geometric transformations, brightness changes and noise. The comparative analysis with the state-of-the-art semantic place description methods show that the method outperforms the competing methods and exhibits better average recognition rates.

    Place, publisher, year, edition, pages
    SPIE - International Society for Optical Engineering, 2013
    Series
    Proceedings of the Society of Photo-Optical Instrumentation Engineers, ISSN 0277-786X ; 9067
    Keyword
    Landmarks; Place recognition; Topological maps; Visual features; Visual navigation
    National Category
    Signal Processing Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-46477 (URN)10.1117/12.2051490 (DOI)000339220200048 ()2-s2.0-84901305228 (Scopus ID)9780819499967 (ISBN)
    Conference
    6th International Conference on Machine Vision (ICMV), London, England, November 16-17, 2013
    Available from: 2015-05-25 Created: 2015-11-12 Last updated: 2018-02-26Bibliographically approved
    3. Bio-inspired Metaheuristic based Visual Tracking and Ego-motion Estimation
    Open this publication in new window or tab >>Bio-inspired Metaheuristic based Visual Tracking and Ego-motion Estimation
    2014 (English)In: Proceedings of the 3rd International Conference on Pattern Recognition Applications and Methods / [ed] Maria De Marsico, Antoine Tabbone and Ana Fred, SciTePress , 2014, p. 569-579Conference paper, Published paper (Refereed)
    Abstract [en]

    The problem of robust extraction of ego-motion from a sequence of images for an eye-in-hand camera configuration is addressed. A novel approach toward solving planar template based tracking is proposed which performs a non-linear image alignment and a planar similarity optimization to recover camera transformations from planar regions of a scene. The planar region tracking problem as a motion optimization problem is solved by maximizing the similarity among the planar regions of a scene. The optimization process employs an evolutionary metaheuristic approach in order to address the problem within a large non-linear search space. The proposed method is validated on image sequences with real as well as synthetic image datasets and found to be successful in recovering the ego-motion. A comparative analysis of the proposed method with various other state-of-art methods reveals that the algorithm succeeds in tracking the planar regions robustly and is comparable to the state-of-the art methods. Such an application of evolutionary metaheuristic in solving complex visual navigation problems can provide different perspective and could help in improving already available methods.

    Place, publisher, year, edition, pages
    SciTePress, 2014
    Keyword
    Camera Tracking, Visual Odometry, Planar Template based Tracking, Particle Swarm Optimization.
    National Category
    Signal Processing Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-46475 (URN)10.5220/0004811105690579 (DOI)2-s2.0-84902308101 (Scopus ID)978-989758018-5 (ISBN)
    Conference
    3rd International Conference on Pattern Recognition Applications and Methods (ICPRAM 2014), Angers, Loire Valley, France, March 6-8, 2014
    Available from: 2014-12-17 Created: 2015-11-12 Last updated: 2018-01-10Bibliographically approved
    4. Robust visual odometry estimation of road vehicle from dominant surfaces for large-scale mapping
    Open this publication in new window or tab >>Robust visual odometry estimation of road vehicle from dominant surfaces for large-scale mapping
    2015 (English)In: IET Intelligent Transport Systems, ISSN 1751-956X, E-ISSN 1751-9578, Vol. 9, no 3, p. 314-322Article in journal (Refereed) Published
    Abstract [en]

    Every urban environment contains a rich set of dominant surfaces which can provide a solid foundation for visual odometry estimation. In this work visual odometry is robustly estimated by computing the motion of camera mounted on a vehicle. The proposed method first identifies a planar region and dynamically estimates the plane parameters. The candidate region and estimated plane parameters are then tracked in the subsequent images and an incremental update of the visual odometry is obtained. The proposed method is evaluated on a navigation dataset of stereo images taken by a car mounted camera that is driven in a large urban environment. The consistency and resilience of the method has also been evaluated on an indoor robot dataset. The results suggest that the proposed visual odometry estimation can robustly recover the motion by tracking a dominant planar surface in the Manhattan environment. In addition to motion estimation solution a set of strategies are discussed for mitigating the problematic factors arising from the unpredictable nature of the environment. The analyses of the results as well as dynamic environmental strategies indicate a strong potential of the method for being part of an autonomous or semi-autonomous system.

    Place, publisher, year, edition, pages
    The Institution of Engineering and Technology, 2015
    Keyword
    object tracking, road safety, distance measurement, stereo image processing, cameras, road vehicles, pose estimation, motion estimation
    National Category
    Signal Processing Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-46478 (URN)10.1049/iet-its.2014.0100 (DOI)000351633300009 ()2-s2.0-84925379428 (Scopus ID)
    Available from: 2015-05-26 Created: 2015-11-12 Last updated: 2018-01-10Bibliographically approved
    5. A novel plane extraction approach using supervised learning
    Open this publication in new window or tab >>A novel plane extraction approach using supervised learning
    2013 (English)In: Machine Vision and Applications, ISSN 0932-8092, E-ISSN 1432-1769, Vol. 24, no 6, p. 1229-1237Article in journal (Refereed) Published
    Abstract [en]

    This paper presents a novel approach for the classification of planar surfaces in an unorganized point clouds. A feature-based planner surface detection method is proposed which classifies a point cloud data into planar and non-planar points by learning a classification model from an example set of planes. The algorithm performs segmentation of the scene by applying a graph partitioning approach with improved representation of association among graph nodes. The planarity estimation of the points in a scene segment is then achieved by classifying input points as planar points which satisfy planarity constraint imposed by the learned model. The resultant planes have potential application in solving simultaneous localization and mapping problem for navigation of an unmanned-air vehicle. The proposed method is validated on real and synthetic scenes. The real data consist of five datasets recorded by capturing three-dimensional(3D) point clouds when a RGBD camera is moved in five different indoor scenes. A set of synthetic 3D scenes are constructed containing planar and non-planar structures. The synthetic data are contaminated with Gaussian and random structure noise. The results of the empirical evaluation on both the real and the simulated data suggest that the method provides a generalized solution for plane detection even in the presence of the noise and non-planar objects in the scene. Furthermore, a comparative study has been performed between multiple plane extraction methods.

    Place, publisher, year, edition, pages
    Springer, 2013
    Keyword
    Autonomous navigation, Planar surfaces, Point cloud, UAV navigation
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-46471 (URN)10.1007/s00138-013-0482-4 (DOI)000321871600009 ()2-s2.0-84880793024 (Scopus ID)
    Available from: 2013-09-10 Created: 2015-11-12 Last updated: 2018-01-10Bibliographically approved
    6. Scene perception by context-aware dominant surfaces
    Open this publication in new window or tab >>Scene perception by context-aware dominant surfaces
    2013 (English)In: Signal Processing and Communication Systems (ICSPCS): Proceedings / [ed] Tadeusz A. Wysocki & Beata J. Wysocki, IEEE , 2013Conference paper, Published paper (Refereed)
    Abstract [en]

    Most of the computer vision algorithms operate pixel-wise and process image in a small neighborhood for feature extraction. Such a feature extraction strategy ignores the context of an object in the real world. Taking geometric context into account while classifying various regions in a scene, we can discriminate the similar features obtained from different regions with respect to their context. A geometric context based scene decomposition method is proposed and is applied in a context-aware Augmented Reality (AR) system. The proposed system segments a single image of a scene into a set of semantic classes representing dominant surfaces in the scene. The classification method is evaluated on an urban driving sequence with labeled ground truths and found to be robust in classifying the scene regions into a set of dominant applicable surfaces. The classified dominant surfaces are used to generate a 3D scene. The generated 3D scene provides an input to the AR system. The visual experience of 3D scene through the contextually aware AR system provides a solution for visual touring from single images as well as an experimental tool for improving the understanding of human visual perception.

    Place, publisher, year, edition, pages
    IEEE, 2013
    Keyword
    geometric cues, image segmentation, scene understanding, single image, surface extraction, visual perception
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-46479 (URN)10.1109/ICSPCS.2013.6723977 (DOI)000345766100076 ()2-s2.0-84903834661 (Scopus ID)978-1-4799-1319-0 (ISBN)
    Conference
    7th International Conference on Signal Processing and Communication Systems (ICSPCS), Gold Coast, Australia, December 16-18, 2013
    Available from: 2015-05-25 Created: 2015-11-12 Last updated: 2018-01-10Bibliographically approved
    7. Semantic indoor maps
    Open this publication in new window or tab >>Semantic indoor maps
    2013 (English)In: Proceedings of 2013 28th International Conference of Image and Vision Computing New Zealand / [ed] Rhee, T; Rayudu, R; Hollitt, C; Lewis, J; Zhang, M, IEEE , 2013, p. 465-470Conference paper, Published paper (Refereed)
    Abstract [en]

    The cumbersome process of construction and incremental update of large indoor maps can be simplified by semantic maps. A novel semantic mapping method for indoor environments is proposed which employs a flash-n-extend strategy for constructing and updating the map. At the exposure of every flash event, a 3D snapshot of the environment is taken which is extended until flash event reoccurs. A flash event occurs at a motion state transition of a mobile robot which is detected by the decomposition of motion estimates. The proposed method is evaluated on a set of image sequences and is found to be robust in building indoor maps which are suitable for robust autonomous navigation. The constructed maps provide simplistic representation of the environment which makes it ideal for high-level reasoning tasks.

    Place, publisher, year, edition, pages
    IEEE, 2013
    Series
    International Conference on Image and Vision Computing New Zealand, ISSN 2151-2191
    Keyword
    indoor, local awareness, Semantic, simultaneous localization and mapping, SLAM, visual navigation
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-46474 (URN)10.1109/IVCNZ.2013.6727059 (DOI)000350291600080 ()2-s2.0-84894293773 (Scopus ID)978-1-4799-0882-0 (ISBN)978-1-4799-0883-7 (ISBN)
    Conference
    28th International Conference on Image and Vision Computing New Zealand (IVCNZ), Wellington, New Zealand, November 27-29, 2013
    Available from: 2015-05-25 Created: 2015-11-12 Last updated: 2018-01-10Bibliographically approved
    8. Semantic Urban Maps
    Open this publication in new window or tab >>Semantic Urban Maps
    2014 (English)In: 22nd International Conference on Pattern Recognition: Proceedings, IEEE conference proceedings, 2014, p. 4050-4055Conference paper, Published paper (Refereed)
    Abstract [en]

    A novel region based 3D semantic mapping method is proposed for urban scenes. The proposed Semantic Urban Maps (SUM) method labels the regions of segmented images into a set of geometric and semantic classes simultaneously by employing a Markov Random Field based classification framework. The pixels in the labeled images are back-projected into a set of 3D point-clouds using stereo disparity. The point-clouds are registered together by incorporating the motion estimation and a coherent semantic map representation is obtained. SUM is evaluated on five urban benchmark sequences and is demonstrated to be successful in retrieving both geometric as well as semantic labels. The comparison with relevant state-of-art method reveals that SUM is competitive and performs better than the competing method in average pixel-wise accuracy.

    Place, publisher, year, edition, pages
    IEEE conference proceedings, 2014
    Series
    International Conference on Pattern Recognition, ISSN 1051-4651
    Keyword
    semantic classification; semantic mapping; visual navigation
    National Category
    Signal Processing Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-46476 (URN)10.1109/ICPR.2014.694 (DOI)000359818004031 ()2-s2.0-84919934206 (Scopus ID)978-1-4799-5208-3 (ISBN)
    Conference
    22nd International Conference on Pattern Recognition (ICPR), Stockholm, Sweden, August 24-28, 2014
    Available from: 2014-12-17 Created: 2015-11-12 Last updated: 2018-01-10Bibliographically approved
  • 800.
    Siddiqui, J. Rafid
    et al.
    Department of Computing, Blekinge Institute of Technology, Karlskrona, Sweden.
    Havaei, Mohammad
    Department of Computing, Blekinge Institute of Technology, Karlskrona, Sweden.
    Khatibi, Siamak
    Department of Computing, Blekinge Institute of Technology, Karlskrona, Sweden.
    Lindley, Craig
    Department of Computing, Blekinge Institute of Technology, Karlskrona, Sweden.
    PLASE: A novel planar surface extraction method for the autonomous navigation of micro-air vehicle2011In: Proceedings of the International Micro Air Vehicles conference 2011, Delft University of Technology and Thales , 2011, p. 48-55Conference paper (Refereed)
    Abstract [en]

    A Planar Surface Extraction (PLASE) method is proposed for the indoor navigation of a micro-air vehicle (MAV). The algorithm finds planar clusters from the unorganized point clouds. This is achieved by implementing a novel approach that first segments the data points into clusters and then each cluster is estimated for its planarity. The method is tested on indoor point cloud data obtained by 3D PrimeSense based sensor. In order to validate the algorithm, a simulated model containing a set of planes has been constructed, with noise injected into the model. The results of the empirical evaluation suggest that the method performs well even in the presence of the noise and non-planar objects, suggesting that the method will be a viable one for use in MAV navigation in the presence of noisy sensor data.

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