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  • 1.
    Afshar, Sara
    et al.
    Mälardalens högskola, Inbyggda system.
    Moghaddami Khalilzad, Nima
    Mälardalens högskola, Inbyggda system.
    Nemati, Farhang
    Mälardalens högskola, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Inbyggda system.
    Resource Sharing among Prioritized Real-Time Applications on Multiprocessors2015Ingår i: ACM SIGBED Review - Special Issue on the 6th International Workshop on Compositional Theory and Technology for Real-Time Embedded Systems Homepage archiveVolume 12 Issue 1, 2015, s. 46-55Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we propose a new protocol for handling resource sharing among prioritized real-time applications composed on a multiprocessor platform. We propose an optimal priority assignment algorithm which assigns unique priorities to the applications based on information in their interfaces. We have performed experimental evaluations to compare the proposed protocol (called MSOS-Priority) to the current state of the art locking protocols under multiprocessor partitioned scheduling, i.e., MPCP, MSRP, FMLP, MSOS, and OMLP. The valuations show that MSOS-Priority mostly performs significantly better than alternative approaches.

  • 2.
    Ahmed, Mobyen Uddin
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Banaee, Hadi
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Health monitoring for elderly: an application using case-based reasoning and cluster analysis2013Ingår i: ISRN Artificial Intelligence, ISSN 2090-7435, E-ISSN 2090-7443, Vol. 2013, nr 2013, s. 1-11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents a framework to process and analyze data from a pulse oximeter which measures pulse rate and blood oxygen saturation from a set of individuals remotely. Using case-based reasoning (CBR) as the backbone to the framework, records are analyzed and categorized according to how well they are similar. Record collection has been performed using a personalized health profiling approach where participants wore a pulse oximeter sensor for a fixed period of time and performed specific activities for pre-determined intervals. Using a variety of feature extraction in time, frequency and time-frequency domains, and data processing techniques, the data is fed into a CBR system which retrieves most similar cases and generates alarm and flag according to the case outcomes. The system has been compared with an expert's classification and 90% match is achieved between the expert's and CBR classification. Again, considering the clustered measurements the CBR approach classifies 93% correctly both for the pulse rate and oxygen saturation. Along with the proposed methodology, this paper provides a basis for which the system can be used in analysis of continuous health monitoring and be used as a suitable method as in home/remote monitoring systems.

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  • 3.
    Ahmed, Mobyen Uddin
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Islam, Asif Moinul
    Örebro University, Örebro, Sweden.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    A case-based patient identification system using pulseoximeter and a personalized health profile2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper proposes a case-based system framework in order to identify patient using their health parameters taken with physiological sensors. It combines a personalized health profiling protocol with a Case-Based Reasoning (CBR) approach. The personalized health profiling helps to determine a number of individual parameters which are important inputs for a clinician to make the final diagnosis and treatment plan. The proposed system uses a pulse oximeter that measures pulse rate and blood oxygen saturation. The measurements are taken through an android application in a smart phone which is connected with the pulseoximeter and bluetooth communication. The CBR approach helps clinicians to make a diagnosis, classification and treatment plan by retrieving the most similar previous case. The case may also be used to follow the treatment progress. Here, the cases are formulated with person’s contextual information and extracted features from sensor signal measurements. The features are extracted considering three domain analysis:1) time domain features using statistical measurement, 2) frequency domain features applying Fast Fourier Transform (FFT), and 3) time-frequency domain features applying Discrete Wavelet Transform (DWT). The initial result is acceptable that shows the advancement of the system while combining the personalized health profiling together with CBR.

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  • 4.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    An Evaluation Tool of the Effect of Robots in Eldercare on the Sense of Safety and Security2017Ingår i: Social Robotics: 9th International Conference, ICSR 2017, Tsukuba, Japan, November 22-24, 2017, Proceedings / [ed] Kheddar, A.; Yoshida, E.; Ge, S.S.; Suzuki, K.; Cabibihan, J-J:, Eyssel, F:, He, H., Springer International Publishing , 2017, s. 628-637Konferensbidrag (Refereegranskat)
    Abstract [en]

    The aim of the study presented in this paper is to develop a quantitative evaluation tool of the sense of safety and security for robots in eldercare. By investigating the literature on measurement of safety and security in human-robot interaction, we propose new evaluation tools. These tools are semantic differential scale questionnaires. In experimental validation, we used the Pepper robot, programmed in the way to exhibit social behaviors, and constructed four experimental conditions varying the degree of the robot’s non-verbal behaviors from no gestures at all to full head and hand movements. The experimental results suggest that both questionnaires (for the sense of safety and the sense of security) have good internal consistency.

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    An Evaluation Tool of the Effect of Robots in Eldercare on the Sense of Safety and Security
  • 5.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    The Relevance of Social Cues in Assistive Training with a Social Robot2018Ingår i: 10th International Conference on Social Robotics, ICSR 2018, Proceedings / [ed] Ge, S.S., Cabibihan, J.-J., Salichs, M.A., Broadbent, E., He, H., Wagner, A., Castro-González, Á., Springer, 2018, s. 462-471Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper examines whether social cues, such as facial expressions, can be used to adapt and tailor a robot-assisted training in order to maximize performance and comfort. Specifically, this paper serves as a basis in determining whether key facial signals, including emotions and facial actions, are common among participants during a physical and cognitive training scenario. In the experiment, participants performed basic arm exercises with a social robot as a guide. We extracted facial features from video recordings of participants and applied a recursive feature elimination algorithm to select a subset of discriminating facial features. These features are correlated with the performance of the user and the level of difficulty of the exercises. The long-term aim of this work, building upon the work presented here, is to develop an algorithm that can eventually be used in robot-assisted training to allow a robot to tailor a training program based on the physical capabilities as well as the social cues of the users.

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    The Relevance of Social Cues in Assistive Training with a Social Robot
  • 6.
    Alirezaie, Marjan
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Längkvist, Martin
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Klügl, Franziska
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    An Ontology-Based Reasoning Framework for Querying Satellite Images for Disaster Monitoring2017Ingår i: Sensors, E-ISSN 1424-8220, Vol. 17, nr 11, artikel-id 2545Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents a framework in which satellite images are classified and augmented with additional semantic information to enable queries about what can be found on the map at a particular location, but also about paths that can be taken. This is achieved by a reasoning framework based on qualitative spatial reasoning that is able to find answers to high level queries that may vary on the current situation. This framework called SemCityMap, provides the full pipeline from enriching the raw image data with rudimentary labels to the integration of a knowledge representation and reasoning methods to user interfaces for high level querying. To illustrate the utility of SemCityMap in a disaster scenario, we use an urban environment—central Stockholm—in combination with a flood simulation. We show that the system provides useful answers to high-level queries also with respect to the current flood status. Examples of such queries concern path planning for vehicles or retrieval of safe regions such as “find all regions close to schools and far from the flooded area”. The particular advantage of our approach lies in the fact that ontological information and reasoning is explicitly integrated so that queries can be formulated in a natural way using concepts on appropriate level of abstraction, including additional constraints.

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  • 7.
    Alirezaie, Marjan
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Towards Automatic Ontology Alignment for Enriching Sensor Data Analysis2013Ingår i: Communications in Computer and Information Science, ISSN 1865-0929, E-ISSN 1865-0937, Vol. 415, s. 179-193Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this work ontology alignment is used to align an ontology comprising high level knowledge to a structure representing the results of low-level sensor data classification. To resolve inherent uncertainties from the data driven classifier, an ontology about application domain is aligned to the classifier output and the result is recommendation system able to suggest a course of action that will resolve the uncertainty. This work is instantiated in a medical application domain where signals from an electronic nose are classified into different bacteria types. In case of misclassifications resulting from the data driven classifier, the alignment to an ontology representing traditional microbiology tests suggests a subset of tests most relevant to use. The result is a hybrid classification system (electronic nose and traditional testing) that automatically exploits domain knowledge in the identification process.

  • 8.
    Alirezaie, Marjan
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Pecora, Federico
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Context Recognition: Towards Automatic Query Generation2015Ingår i: Ambient Intelligence: 12th European Conference, AmI 2015, Athens, Greece, November 11-13, 2015, Proceedings, Springer, 2015, s. 205-218Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we present an ontology-based approach in designing knowledge model for context recognition (CR) systems. The main focus in this paper is on the use of an ontology to facilitate the generation of user-based queries to the CR system. By leveraging from the ontology, users need not know about sensor details and the structure of the ontology in expressing queries related to events of interest. To validate the approach and demonstrate the flexibility of the ontology for query generation, the ontology has been integrated in two separate application domains. The first domain considers a health care system implemented for the GiraffPlus project where the query generation process is automated to request information about activities of daily living. The second application uses the same ontology for an air quality monitoring application in the home. Since these two systems are independently developed for different purposes, the ease of applying the ontology upon them can be considered as a credit for its generality.

  • 9.
    Alirezaie, Marjan
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Renoux, Jennifer
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Köckemann, Uwe
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Blomqvist, Eva
    RISE SICS East, Linköping, Sweden.
    Tsiftes, Nicolas
    RISE SICS, Stockholm, Sweden.
    Voigt, Thiemo
    RISE SICS, Stockholm, Sweden.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    An Ontology-based Context-aware System for Smart Homes: E-care@home2017Ingår i: Sensors, E-ISSN 1424-8220, Vol. 17, nr 7, artikel-id 1586Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Smart home environments have a significant potential to provide for long-term monitoring of users with special needs in order to promote the possibility to age at home. Such environments are typically equipped with a number of heterogeneous sensors that monitor both health and environmental parameters. This paper presents a framework called E-care@home, consisting of an IoT infrastructure, which provides information with an unambiguous, shared meaning across IoT devices, end-users, relatives, health and care professionals and organizations. We focus on integrating measurements gathered from heterogeneous sources by using ontologies in order to enable semantic interpretation of events and context awareness. Activities are deduced using an incremental answer set solver for stream reasoning. The paper demonstrates the proposed framework using an instantiation of a smart environment that is able to perform context recognition based on the activities and the events occurring in the home.

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  • 10.
    ANGELONE, MARIA LAURA
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    AndroidOS- Robot Command Interface2011Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 11.
    Arain, Muhammad Asif
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Havoutis, Ioannis
    Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy.
    Semini, Claudio
    Department of Advanced Robotics,Istituto Italiano di Tecnologia, Genova, Italy.
    Buchli, Jonas
    Eidgenössische Technische Hochschule Zürich (ETH), Zurich, Schweiz.
    Caldwell, Darwin G.
    Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy.
    A comparison of search-based planners for a legged robot2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    Path planning for multi-DoF legged robots is achallenging task due to the high dimensionality and complexityof the planning space. We present our first attempt to builda path planning framework for the hydraulic quadruped -HyQ. Our approach adopts a similar strategy to [1], whereplanning is divided into a task-space and a joint-space part.The task-space planner finds a path for the center of gravity(COG) of the robot, while then the footstep planner generates theappropriate footholds under reachability and stability criteria.Next the joint-space planner translates the task-space COGtrajectories into robot joint angles. We present a comparisonof a set of search-based planning algorithms; Dijkstra, A* andARA*, and evaluate these over a set of given terrains and anumber of varying start and end points. All test runs supportthat our approach is a simple yet robust solution. We reportcomparisons in path length, computation time, and path cost,between the aforementioned planning algorithms.

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    Arain_RoMoCo13
  • 12.
    Arain, Muhammad Asif
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Schaffernicht, Erik
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Hernandez Bennetts, Victor
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    The Right Direction to Smell: Efficient Sensor Planning Strategies for Robot Assisted Gas Tomography2016Ingår i: 2016 IEEE International Conference on Robotics and Automation (ICRA), New York, USA: IEEE Robotics and Automation Society, 2016, s. 4275-4281Konferensbidrag (Refereegranskat)
    Abstract [en]

    Creating an accurate model of gas emissions is an important task in monitoring and surveillance applications. A promising solution for a range of real-world applications are gas-sensitive mobile robots with spectroscopy-based remote sensors that are used to create a tomographic reconstruction of the gas distribution. The quality of these reconstructions depends crucially on the chosen sensing geometry. In this paper we address the problem of sensor planning by investigating sensing geometries that minimize reconstruction errors, and then formulate an optimization algorithm that chooses sensing configurations accordingly. The algorithm decouples sensor planning for single high concentration regions (hotspots) and subsequently fuses the individual solutions to a global solution consisting of sensing poses and the shortest path between them. The proposed algorithm compares favorably to a template matching technique in a simple simulation and in a real-world experiment. In the latter, we also compare the proposed sensor planning strategy to the sensing strategy of a human expert and find indications that the quality of the reconstructed map is higher with the proposed algorithm.

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    Arain_etal_ICRA-2016
  • 13.
    Arunachalam, Ajay
    et al.
    Department of Computer Science, Graduate School of Applied Statistics, National Institute of Development Administration, Thailand.
    Sornil, Ohm
    Department of Computer Science, Graduate School of Applied Statistics, National Institute of Development Administration, Thailand.
    A broadcast based random query gossip algorithm for resource search in non-DHT mobile Peer-to-Peer networks2017Ingår i: Diànnǎo xuékān (Journal of Computers), ISSN 1991-1599, Vol. 28, nr 1, s. 209-223Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents a resource discovery scheme for decentralized non-DHT Mobile Peer-to-Peer (MP2P) networks. In a mobile environment, the energy of mobile device is very critical. The aim of the proposed technique is to reduce the network overhead, lower battery power consumption and minimize query delay while improving the chance to resolve the query at every successive stage. Peer-to-Peer applications have gained a lot of attention in past years due to its decentralized nature. Resource searching algorithms are one of the major focuses of P2P network. Mobile Ad hoc Network (MANET) with its changing topology further poses additional challenges and thus increasing the search effort. Methods like flooding, random walk and probabilistic forwarding techniques are good candidates to run over such dynamic network. In this work, we study the flooding, random walk and gossip based resource discovery protocols on a P2P Mobile Ad hoc Network. We observed that the classic gossip algorithm does not work well under MANET as in the case of a wired network. We focus to improve the algorithm to suit and work better under such dynamic network scenario. The proposed system presents a light weight resource discovery design to suit the mobility requirement of ad hoc networks to optimize the search performance while at the same time minimize the extra usage of mobile and network resources. For quick and energy efficient search scheme, we explore a novel addressed jumping approach. Our algorithm is entirely distributed, and hence will scale well even to the growing size of the network. The efficiency of our proposed algorithm is validated through extensive NS-2 simulations. The results show that our proposed scheme gives better performance than the widely used techniques. We also validate through statistical hypothesis testing of simulation data.

  • 14.
    Arunachalam, Ajay
    et al.
    Department of Computer Science, School of Applied Statistics, National Institute of Development Administration, Bangkok, Thailand.
    Sornil, Ohm
    Department of Computer Science, School of Applied Statistics, National Institute of Development Administration, Bangkok, Thailand.
    Reducing Routing Overhead in random walk protocol under MP2P Network2016Ingår i: International Journal of Electrical and Computer Engineering, ISSN 2088-8708, Vol. 6, nr 6, s. 3121-3130Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to network dynamics in self-organizing networks the resource discovery effort increases. To discover objects in unstructured peer-to-peer network, peers rely on traditional methods like flooding, random walk and probabilistic forwarding methods. With inadequate knowledge of paths, the peers have to flood the query message which creates incredible network traffic and overhead. Many of the previous works based on random walk were done in wired network. In this context random walk was better than flooding. But under MANETs random walk approach behaved differently increasing the overhead, due to frequent link failures incurred by mobility. Decentralized applications based on peer-to-peer computing are best candidates to run over such dynamic network. Issues of P2P service discovery in wired networks have been well addressed in several earlier works. This article evaluates the performance of random walk based resource discovery protocol over P2P Mobile Adhoc Network (MP2P) and suggests an improved scheme to suit MANET. Our version reduces the network overhead, lowers the battery power consumption, minimizes the query delay while providing equally good success rate. The protocol is validated through extensive NS-2 simulations. It is clear from the results that our proposed scheme is an alternative to the existing ones for such highly dynamic mobile network scenario.

  • 15.
    Banaee, Hadi
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ahmed, Mobyen Uddin
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Towards NLG for Physiological Data Monitoring with Body Area Networks2013Ingår i: 14th European Workshop on Natural Language Generation, 2013, s. 193-197Konferensbidrag (Refereegranskat)
    Abstract [en]

    This position paper presents an on-goingwork on a natural language generationframework that is particularly tailored fornatural language generation from bodyarea networks. We present an overview ofthe main challenges when considering thistype of sensor devices used for at homemonitoring of health parameters. The paperpresents the first steps towards the implementationof a system which collectsinformation from heart rate and respirationusing a wearable sensor.

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  • 16.
    Bandaru, Vamsi Krishna
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Balasubramanian, Rajasekaran
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    OBJECT RECOGNITION USINGDIALOGUES AND SEMANTICANCHORING2013Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This report explains in detail the implemented system containing a robot and a sensor

    network that is deployed in a test apartment in an elderly residence area. The report

    focuses on the creation and maintenance (anchoring) of the connection between the

    semantic information present in the dialog with perceived actual physical objects in the

    home. Semantic knowledge about concepts and their correlations are retrieved from online

    resources and ontologies, e.g. Word-Net and sensors information are provided by

    cameras distributed in the apartment.

    Ladda ner fulltext (pdf)
    fulltext
  • 17.
    Blomqvist, Eva
    et al.
    Linköping University, Linköping, Sweden.
    Alirezaie, Marjan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Santini, Marina
    RISE, Research Institutes of Sweden.
    Towards Causal Knowledge Graphs - Position Paper2020Ingår i: Proceedings of the 5th International Workshop on Knowledge Discovery in Healthcare Data co-located with 24th European Conference on Artificial Intelligence (ECAI 2020) / [ed] Kerstin Bach, Razvan Bunescu, Cindy Marling, Nirmalie Wiratunga, Technical University of Aachen , 2020, Vol. 2675, s. 58-62Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this position paper, we highlight that being able to analyse the cause-effect relationships for determining the causal status among a set of events is an essential requirement in many contexts and argue that cannot be overlooked when building systems targeting real-world use cases. This is especially true for medical contexts where the understanding of the cause(s) of a symptom, or observation, is of vital importance. However, most approaches purely based on Machine Learning (ML) do not explicitly represent and reason with causal relations, and may therefore mistake correlation for causation. In the paper, we therefore argue for an approach to extract causal relations from text, and represent them in the form of Knowledge Graphs (KG), to empower downstream ML applications, or AI systems in general, with the ability to distinguish correlation from causation and reason with causality in an explicit manner. So far, the bottlenecks in KG creation have been scalability and accuracy of automated methods, hence, we argue that two novel features are required from methods for addressing these challenges, i.e. (i) the use of Knowledge Patterns to guide the KG generation process towards a certain resulting knowledge structure, and (ii) the use of a semantic referee to automatically curate the extracted knowledge. We claim that this will be an important step forward for supporting interpretable AI systems, and integrating ML and knowledge representation approaches, such as KGs, which should also generalise well to other types of relations, apart from causality.

  • 18.
    Bouguerra, Abdelbaki
    Örebro universitet, Institutionen för teknik.
    A reactive approach for object finding in real world environments2006Ingår i: Intelligent Autonomous Systems 9 / [ed] Tamio Arai, Rolf Pfeifer, Tucker Balch, Hiroshi Yokoi, 2006, s. 391-398Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In this paper we propose an approach to handle requests of finding objects in real world environments by mobile robots. The proposed approach checks candidate objects based on the likelihood they constitute an answer to the requests in a reactive way. As a result, run-time perceived objects are handled “on the fly” without extra cost. We present the theoretical concepts of the proposed approach, and describe the experiments we run to validate it.

  • 19.
    Canelhas, Daniel Ricão
    et al.
    Univrses AB, Strängnäs, Sweden.
    Stoyanov, Todor
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    A Survey of Voxel Interpolation Methods and an Evaluation of Their Impact on Volumetric Map-Based Visual Odometry2018Ingår i: Proceedings of the IEEE International Conference on Robotics and Automation (ICRA),, IEEE Computer Society, 2018, s. 6337-6343Konferensbidrag (Refereegranskat)
    Abstract [en]

    Voxel volumes are simple to implement and lend themselves to many of the tools and algorithms available for 2D images. However, the additional dimension of voxels may be costly to manage in memory when mapping large spaces at high resolutions. While lowering the resolution and using interpolation is common work-around, in the literature we often find that authors either use trilinear interpolation or nearest neighbors and rarely any of the intermediate options. This paper presents a survey of geometric interpolation methods for voxel-based map representations. In particular we study the truncated signed distance field (TSDF) and the impact of using fewer than 8 samples to perform interpolation within a depth-camera pose tracking and mapping scenario. We find that lowering the number of samples fetched to perform the interpolation results in performance similar to the commonly used trilinear interpolation method, but leads to higher framerates. We also report that lower bit-depth generally leads to performance degradation, though not as much as may be expected, with voxels containing as few as 3 bits sometimes resulting in adequate estimation of camera trajectories.

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    A Survey of Voxel Interpolation Methods and an Evaluation of Their Impact on Volumetric Map-Based Visual Odometry
  • 20.
    Chakraborty, Subham
    et al.
    Innopolis University, Universitetskaya, Innopolis, Russia.
    Thapaliya, Ananga
    Innopolis University, Universitetskaya, Innopolis, Russia.
    Above the Clouds: A Brief Study2019Ingår i: Software Technology: Methods and Tools / [ed] Manuel MazzaraJean-Michel BruelBertrand MeyerAlexander Petrenko, Springer, 2019, Vol. 11771, s. 326-333Konferensbidrag (Refereegranskat)
    Abstract [en]

    Cloud Computing is a versatile technology that can support a broad-spectrum of applications. The low cost of cloud computing and its dynamic scaling renders it an innovation driver for small companies, particularly in the developing world. Cloud deployed enterprise resource planning (ERP), supply chain management applications (SCM), customer relationship management (CRM) applications, medical applications, business applications and mobile applications have potential to reach millions of users. In this paper, we explore the different concepts involved in cloud computing and we also examine clouds from technical aspects. We highlight some of the opportunities in cloud computing underlining the importance of clouds showing why that technology must succeed and we have provided additional cloud computing problems that businesses may need to address. Finally, we discuss some of the issues that this area should deal with.

  • 21.
    Fouladgar, Nazanin
    et al.
    Department of Computing Science, Umeå University, Sweden.
    Alirezaie, Marjan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Främling, Kary
    Department of Computing Science, Umeå University, Sweden; Aalto University, School of Science and Technology, Finland.
    Decision Explanation: Applying Contextual Importance and Contextual Utility in Affect Detection2020Ingår i: Proceedings of the Italian Workshop on Explainable Artificial Intelligence co-located with 19th International Conference of the Italian Association for Artificial Intelligence(AIxIA 2020) / [ed] Cataldo Musto, Daniele Magazzeni, Salvatore Ruggieri, Giovanni Semeraro, Technical University of Aachen , 2020, s. 1-13Konferensbidrag (Refereegranskat)
    Abstract [en]

    Explainable AI has recently paved the way to justify decisions made by black-box models in various areas. However, a mature body of work in the field of affect detection is still limited. In this work, we evaluate a black-box outcome explanation for understanding humans’ affective states. We employ two concepts of Contextual Importance (CI) and Contextual Utility (CU), emphasizing on a context-aware decision explanation of a non-linear model, mainly a neural network. The neural model is designed to detect the individual mental states measured by wearable sensors to monitor the human user’s well-being. We conduct our experiments and outcome explanation on WESAD and MAHNOB-HCI, as multimodal affect computing datasets. The results reveal that in the first experiment the electrodermal activity, respiration as well as accelorometer and in the second experiment the electrocardiogram and respiration signals contribute significantly in the classification task of mental states for a specific participant. To the best of our knowledge, this is the first study leveraging the CI and CU concepts in outcome explanation of an affect detection model.

  • 22. Galindo, Cipriano
    et al.
    González, Javier
    Fernández-Madrigal, Juan-Antonio
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Robots that change their world: inferring goals from semantic knowledge2011Ingår i: Proceedings of the 5th European Conference on Mobile Robots, ECMR 2011 / [ed] Achim J. Lilienthal, Tom Duckett, 2011, s. 1-6Konferensbidrag (Refereegranskat)
  • 23.
    Giaretta, Alberto
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Dragoni, Nicola
    Örebro universitet, Institutionen för naturvetenskap och teknik. DTU Compute, Technical University of Denmark, Lyngby, Denmark.
    Massacci, Fabio
    Department of Information Science and Engineering, University of Trento, Trento, Italy.
    IoT Security Configurability with Security-by-Contract2019Ingår i: Sensors, E-ISSN 1424-8220, Vol. 19, nr 19, artikel-id E4121Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cybersecurity is one of the biggest challenges in the Internet of Things (IoT) domain, as well as one of its most embarrassing failures. As a matter of fact, nowadays IoT devices still exhibit various shortcomings. For example, they lack secure default configurations and sufficient security configurability. They also lack rich behavioural descriptions, failing to list provided and required services. To answer this problem, we envision a future where IoT devices carry behavioural contracts and Fog nodes store network policies. One requirement is that contract consistency must be easy to prove. Moreover, contracts must be easy to verify against network policies. In this paper, we propose to combine the security-by-contract (S × C) paradigm with Fog computing to secure IoT devices. Following our previous work, first we formally define the pillars of our proposal. Then, by means of a running case study, we show that we can model communication flows and prevent information leaks. Last, we show that our contribution enables a holistic approach to IoT security, and that it can also prevent unexpected chains of events.

  • 24.
    Giaretta, Alberto
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Dragoni, Nicola
    DTU Compute, Technical University of Denmark, Kongens Lyngby, Denmark.
    Massacci, Fabio
    Department of Information Sciences and Engineering, University of Trento, Italy; Vrije Universiteit Amsterdam, Netherlands.
    S×C4IoT: A Security-by-contract Framework for Dynamic Evolving IoT Devices2022Ingår i: ACM transactions on sensor networks, ISSN 1550-4867, E-ISSN 1550-4859, Vol. 18, nr 1, artikel-id 12Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Internet of Things (IoT) revolutionised the way devices, and human beings, cooperate and interact. The interconnectivity and mobility brought by IoT devices led to extremely variable networks, as well as unpredictable information flows. In turn, security proved to be a serious issue for the IoT, far more serious than it has been in the past for other technologies. We claim that IoT devices need detailed descriptions of their behaviour to achieve secure default configurations, sufficient security configurability, and self-configurability. In this article, we propose S×C4IoT, a framework that addresses these issues by combining two paradigms: Security by Contract (S×C) and Fog computing. First, we summarise the necessary background such as the basic S×C definitions. Then, we describe how devices interact within S×C4IoT and how our framework manages the dynamic evolution that naturally result from IoT devices life-cycles. Furthermore, we show that S×C4IoT can allow legacy S×C-noncompliant devices to participate with an S×C network, we illustrate two different integration approaches, and we show how they fit into S×C4IoT. Last, we implement the framework as a proof-of-concept. We show the feasibility of S×C4IoT and we run different experiments to evaluate its impact in terms of communication and storage space overhead.

    Ladda ner fulltext (pdf)
    S×C4IoT: A Security-by-contract Framework for Dynamic Evolving IoT Devices
  • 25.
    Grantner, Janos L.
    et al.
    Western Michigan University, Dept. of Electrical and Computer Engineering, USA.
    Fodor, George. A.
    ABB Automation Products AB, Västerås, Sweden; Western Michigan University, Dept. of Electrical and Computer Engineering, USA.
    Driankov, Dimiter
    Department of Information and Computer Science, University of Linköping, Linköping, Sweden.
    The virtual fuzzy state machine approach: a domain-independent fault detection and recovery method for object-based control systems1999Ingår i: Proceedings of the 18th International Conference of the North American  Fuzzy Information Processing Society (NAFIPS), IEEE conference proceedings, 1999, s. 158-162Konferensbidrag (Refereegranskat)
    Abstract [en]

    The current trend of using object based design for real time control systems has the implication that traditional state based fault detection and recovery methods cannot be used directly. This problem is even more difficult for domain independent fault detection and recovery since most such methods are based on a formal analysis of the global state set. The paper presents a domain independent fault isolation, detection and recovery method for object based control systems based on constraints of the object architecture. Variations of the control behavior from normal cases are detected using a fuzzy state machine approach

  • 26.
    Gupta, Puneet Kumar
    et al.
    Independent Accessible Media Professional, Meerut, India.
    Mathew Martin, Poothullil John
    Department of Outreach & Extension Services, Ali Yavar Jung National Institute for the Hearing Handicapped, Mumbai, India.
    Comprehension of basic mathematics among children with hearing impairment using multimedia in accesible and non-accesible format a comparative study2013Ingår i: 2013 IEEE 63rd Annual Conference International Council for Educational Media (ICEM), IEEE conference proceedings, 2013, s. 1-11Konferensbidrag (Refereegranskat)
    Abstract [en]

    Teaching mathematics has been a complex issue for educators as well as learners. Same is the condition for the hearing impaired learners. Multimedia can be a big facilitator in order to render simpler and effective learning methods in the field of teaching mathematics to the hearing impaired students. The guidelines of United Nations Convention of Rights of Persons with Disabilities (UNCRPD, 2007), makes provision for creation of information in accessible format.

    However there are no research studies to establish that teaching mathematics through the accessible format of multimedia would increase comprehension levels in children with hearing impairment. According to Mary Ellen Foster (2003) in her study on visual comprehension found that ‘Intuitively, one way of determining the usefulness of any presentation of data is by measuring the ease with which tasks involving that data can be performed using that presentation’.

    It may be noted that children with hearing impairment use visual techniques in their thought process, therefore accessible format of multimedia will enhance their comprehension levels. Accessible format includes techniques such as captioning, sign language and audio Description.

    This can be very helpful in processing information by hearing impaired children. The study investigated the effects of multimedia in accessible format, through the use of captioning and Indian sign language (ISL), on hearing impaired children. Hearing impaired viewers watched twice, the short multimedia with and without accessibility formats respectively. Their reactions were recorded on a questionnaire developed for the purpose of the study.

    Forty nine students participated in this study from two deaf schools of Mumbai,India. Analysis of the data showed that there was difference in the effects of accessible and non accessible formats of on the Hearing Impaired viewers.

    The study also showed that accessible formats increase the comprehension of the subject of the multimedia and use of ISL and captioning helped hearing impaired students to understand concepts better. The hearing impaired persons correlated watching the ISL interpreter with understanding the concept of the topic of multimedia. Placement of the ISL interpreter in the screen was also covered under the study.

  • 27.
    Ishida, Hiroshi
    et al.
    Tokyo University of Agriculture and Technology, Tokyo, Japan.
    Lilienthal, Achim J.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Matsukura, Haruka
    Tokyo University of Agriculture and Technology, Tokyo, Japan.
    Hernandez Bennetts, Victor
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Schaffernicht, Erik
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Using Chemical Sensors as 'Noses' for Mobile Robots2016Ingår i: Essentials of Machine Olfaction and Taste / [ed] Takamichi Nakamoto, Singapore: John Wiley & Sons, 2016, s. 219-246Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Gas sensors detect the presence of gaseous chemical compounds in air. They are often used in the form of gas alarms for detecting dangerous or hazardous gases. However, a limited number of stationary gas alarms may not be always sufficient to cover a large industrial facility. Human workers having a portable gas detector in their hand needs to be sent to thoroughly check gas leaks in the areas not covered by stationary gas alarms. However, making repetitive measurements with a gas detector at a number of different locations is laborious. Moreover, the places where the gas concentration level needs to be checked are often potentially dangerous for human workers. If a portable gas detector is mounted on a mobile robot, the task of patrolling in an industrial facility for checking a gas leak can be automated. Robots are good at doing repetitive tasks, and can be sent into harsh environments.

  • 28.
    Junges, Robert
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Klügl, Franziska
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Behavior modeling from learning agents: sensitivity to objective function details2012Ingår i: Proceedings of the 11th International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2012): volume 3 / [ed] Conitzer,Winikoff, Padgham, and van der Hoek, Richland SC: The International Foundation for Autonomous Agents and Multiagent Systems (IFAAMAS), 2012, s. 1335-1336Konferensbidrag (Refereegranskat)
    Abstract [en]

    The process of finding the appropriate agent behavior is a cumbersome task – no matter whether it is for agent-based software or simulation models. Machine Learning can help by generating partial or preliminary versions of the agent low-level behavior. However, for actually being useful for the human modeler the results should be interpretable, which may require some post-processing step after the actual behavior learning. In this contribution we test the sensitivity of the resulting, interpretable behavior program with respect to parameters and components of the function that describes the intended behavior.

  • 29.
    Junges, Robert
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Klügl, Franziska
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    How to design agent-based simulation models using agent learning2012Ingår i: Winter Simulation Conference Proceedings, Institute of Electrical and Electronics Engineers (IEEE), 2012, s. 1-10Konferensbidrag (Refereegranskat)
    Abstract [en]

    The question of what is the best way to develop an agent-based simulation model becomes more important as this paradigm is more and more used. Clearly, general model development processes can be used, but these do not solve the major problems of actually deciding about the agents' structure and behavior. In this contribution we introduce the MABLe methodology for analyzing and designing agent simulation models that relies on adaptive agents, where the agent helps the modeler by proposing a suitable behavior program. We test our methodology in a pedestrian evacuation scenario. Results demonstrate the agents can learn and report back to the modeler a behavior that is interestingly better than a hand-made model.

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    How to design agent-based simulation models using agent learning
  • 30.
    Kajtazi, Miranda
    et al.
    Lund University, Lund, Sweden.
    Haftor, Darek
    Institutionen för datavetenskap, fysik och matematik (DFM), Linnéuniversitetet, Växjö, Sweden.
    Information Inadequacy: Instances that Causes the Lack of Needed Information2012Ingår i: The 5th Workshop on Information Logistics and Knowledge Supply (ILOG2012), at the 11th International Conference on Perspectives in Business Informatics Research (BIR2012): Nizhny Novgorod, Russia, September 24-26, 2012. Proceedings: “Satellite Workshops & Doctoral Consortium.”, Springer, 2012, s. 7-17Konferensbidrag (Refereegranskat)
  • 31.
    Kalidindi, Sai Sushanth Varma
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Banaee, Hadi
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Transformers and Contextual Information in Temperature Prediction of Residential Buildings for Improved Energy Consumption2022Konferensbidrag (Refereegranskat)
    Abstract [en]

    Energy optimization plays a vital role in decreasing the carbon footprint of residential buildings. In this paper, we present a prediction model of indoor temperature in residential buildings in three different case studies in different towns in Sweden. To predict the indoor temperature accurately, a dataset based on several years of data collection (up to 7 years) has been used. This paper applies both the traditional LSTM model as well as the more recent transformer model. The latter has been used because of its ability to perform a mechanism of self-attention that shows particular promise in multivariate sensor data. In addition to these algorithms, the data set is also modified based on contextual information and compared against an approach where no contextual information is used. Contextual information in this case takes into account the physical location of specific apartment units within the full residence and builds individual models based on the location of the unit. The results demonstrate that transformers are better suited for task of prediction, and that transformers combined with contextual information, provide a suitable approach for energy consumption prediction. 

    Ladda ner fulltext (pdf)
    Transformers and Contextual Information in Temperature Prediction of Residential Buildings for Improved Energy Consumption
  • 32.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Bernon, Carole
    Paul Sabatier University, Toulouse, France.
    Self-Adaptive Agents for Debugging Multi-Agent Simulations2011Ingår i: Proc. of the 3rd ADAPTIVE 2011: The Third International Conference on Adaptive and Self-Adaptive Systems and Applications / [ed] J. Fox and A. Rausch, Xpert Publishing Services, 2011, s. 79-84Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this contribution, we propose an adaptation-drivenmethodology for the technical design and implementation of multi-agent simulations that is inspired by the concept of "living design". The simulated agents are capable of evaluatingtheir behavior and self-adapt for improving the overall model.For this aim, the modeler describes critical, non valid situations in the life of an agent, or the complete agent system, and explicitly specifies repair knowledge for these situations.

    Ladda ner fulltext (pdf)
    ADAPTIVE2011_KluglBernon
  • 33.
    Klügl, Franziska
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Towards Pattern-Oriented Design of Agent-Based Simulation Models2009Ingår i: MULTI-AGENT SYSTEM TECHNOLOGIES, PROCEEDINGS / [ed] Braubach, L; VanderHoek, W; Petta, P; Pokahr, A, Berlin, Germany: Springer, 2009, s. 41-53Konferensbidrag (Refereegranskat)
    Abstract [en]

    The formalization and use of experiences in good model design would make an important contribution to increasing the efficiency of modeling as well as to supporting the knowledge transfer from experienced modelers to modeling novices. We propose to address this problem by providing a set of model design patterns inspired by patterns in Software Engineering for capturing the reusable essence of a solution to specific partial modeling problem. This contribution provides a First step formulating the vision and indicating how patterns and which types of patterns can play a role in agent-based model design.

  • 34.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ossowski, SaschaUniversity Rey Juan Carlos, Madrid, Spain.
    Multiagent system technologies: 8th German Conference, MATES 2011, Berlin, Germany, October 6-7, 2011. Proceedings2011Proceedings (redaktörskap) (Refereegranskat)
    Abstract [en]

    This book constitutes the proceedings of the 9th German Conference on Multiagent System Technologies held in Berlin, Germany, in October 2011. The 12 revised full papers presented together with 6 short parers were carefully reviewed and selected from 50 submissions. Providing an interdisciplinary forum for researchers, users, and developers to present and discuss latest advances in research work as well as prototyped or fielded systems of intelligent agents and multi-agent systems, the papers cover the whole range of this sector and promote its theory and applications.

  • 35.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Rindsfüser, Guido
    Emch&Berger AG, Bern, Switzerland.
    Agent-based route (and mode) choice simulation in real-world networks2011Ingår i: 2011 IEEE/WIC/ACM International Conference on  Web Intelligence and Intelligent Agent Technology (WI-IAT) / [ed] Jomi F. Hübner, Jean-Marc Petit, Einoshin Suzuki, IEEE, 2011, s. 22-29Konferensbidrag (Refereegranskat)
    Abstract [en]

    Mode and route choice are central elements of traffic simulations. Traditionally they form two subsequent steps in the four-step process where first, the simulated population distributes among available transportation modes and then their movement is assigned to the roads respectively other networks. However, these two phases are better dealt with simultaneously as choices are highly depending on each other. In this paper, we are suggesting an agent-based combined route and mode choice model that is not only able to resemble traditional simulations, but provides the means for new applications. As the simulated agents are active and situated while moving through the network, they are able to react to unforeseen events such as the closing of a link. Thus we can reproduce the self-organized re-distribution of travelers to new routes depending on when/where they are notified about the problem. We illustrate the feasibility and usefulness of our agent-based mode and route choice simulation using a real-world network of a small-size Swiss town.

  • 36.
    Kondyli, Vasiliki
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Bhatt, Mehul
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Evaluating Artificial Vision in AI Systems: The Case of Autonomous Driving2021Ingår i: Perception, ISSN 0301-0066, E-ISSN 1468-4233, Vol. 50, nr 1 Suppl., s. 221-222Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    We develop a cognitive evaluation schema for analysing the diversity and nuances of visuospatial complexity and multimodal interactions encountered in naturalistic everyday driving conditions. The proposed schema is based on a finegrained empirical analysis of real-world everyday driving situations involving stakeholders such as drivers, pedestrians, cyclists. Our method involves a semantic analysis of egocentric POVs of stakeholders, focusing on the sequence and duration of events (e.g. velocity or direction change), the combination of modalities used (e.g., gestures, gaze, head-movements), audio, quantity and variety of moving and static objects in the scene e.g., (cars, signs), behavioural metrics from the stakeholders (e.g. gaze allocation, steering), etc. The proposed cognitive evaluation schema consists of three key aspects: (1) Scene characteristics consisting of a combination of quantitative (e.g., clutter, size), structural (e.g. symmetry), and dynamic attributes (e.g. motion), (2) Multimodal interactions consisting of the mode and method of interaction, as well as the level of joint attention achieved, (3) Recipient effects characterising subject’s behaviour and driving performance through physiological measurements (e.g. eye-tracking, head rotation) in a series of virtual reality (VR) environments replicating a number of naturalistic scenarios (and variations therefrom). Driven by behavioural methods in visual perception, we aim to open-up an interdisciplinary frontier for the human-centred design, evaluation / testing of artificial vision modules within AI-technologies for autonomous driving, cognitive robotics etc., where embodied, multimodal human-machine interaction is of the essence. We also demonstrate the practical application of basic visual perception research towards technology-centric settings of social significance.

  • 37.
    Krug, Robert
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Stoyanov, Todor
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Lilienthal, Achim
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Grasp Envelopes for Constraint-based Robot Motion Planning and Control2015Ingår i: Robotics: Science and Systems Conference: Workshop on Bridging the Gap between Data-driven and Analytical Physics-based Grasping and Manipulation, 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    We suggest a grasp represen-tation in form of a set of enveloping spatial constraints. Our representation transforms the grasp synthesisproblem (i. e., the question of where to position the graspingdevice) from finding a suitable discrete manipulator wrist pose to finding a suitable pose manifold. Also the correspondingmotion planning and execution problem is relaxed – insteadof transitioning the wrist to a discrete pose, it is enough tomove it anywhere within the grasp envelope which allows toexploit kinematic redundancy.

    Ladda ner fulltext (pdf)
    fulltext
  • 38.
    Kucner, Tomasz
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Magnusson, Martin
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Schaffernicht, Erik
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Hernandez Bennetts, Victor
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Lilienthal, Achim
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Tell me about dynamics!: Mapping velocity fields from sparse samples with Semi-Wrapped Gaussian Mixture Models2016Ingår i: Robotics: Science and Systems Conference (RSS 2016), 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Autonomous mobile robots often require informa-tion about the environment beyond merely the shape of thework-space. In this work we present a probabilistic method formappingdynamics, in the sense of learning and representingstatistics about the flow of discrete objects (e.g., vehicles, people)as well as continuous media (e.g., air flow). We also demonstratethe capabilities of the proposed method with two use cases. Onerelates to motion planning in populated environments, whereinformation about the flow of people can help robots to followsocial norms and to learn implicit traffic rules by observingthe movements of other agents. The second use case relates toMobile Robot Olfaction (MRO), where information about windflow is crucial for most tasks, including e.g. gas detection, gasdistribution mapping and gas source localisation. We representthe underlying velocity field as a set of Semi-Wrapped GaussianMixture Models (SWGMM) representing the learnt local PDF ofvelocities. To estimate the parameters of the PDF we employ aformulation of Expectation Maximisation (EM) algorithm specificfor SWGMM. We also describe a data augmentation methodwhich allows to build a dense dynamic map based on a sparseset of measurements. In case only a small set of observations isavailable we employ a hierarchical sampling method to generatevirtual observations from existing mixtures.

    Ladda ner fulltext (pdf)
    fulltext
  • 39.
    Landin, Cristina
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik. Product Development Unit Radio, Production Test Development, Ericsson AB, Kumla, Sweden.
    Hatvani, Leo
    School of Innovation, Design and Engineering, Mälardalen University, Västerås, Sweden.
    Tahvili, Sahar
    Global Artificial Intelligence Accelerator (GAIA), Ericsson AB, Stockholm, Sweden; School of Innovation, Design and Engineering, Mälardalen University, Västerås, Sweden.
    Haggren, Hugo
    Global Artificial Intelligence Accelerator (GAIA), Ericsson AB, Stockholm, Sweden.
    Längkvist, Martin
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Håkansson, Anne
    School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Stockholm, Sweden.
    Performance Comparison of Two Deep Learning Algorithms in Detecting Similarities Between Manual Integration Test Cases2020Ingår i: The Fifteenth International Conference on Software Engineering Advances, International Academy, Research and Industry Association (IARIA) , 2020, s. 90-97Konferensbidrag (Refereegranskat)
    Abstract [en]

    Software testing is still heavily dependent on human judgment since a large portion of testing artifacts, such as requirements and test cases are written in a natural text by experts. Identifying and classifying relevant test cases in large test suites is a challenging and also time-consuming task. Moreover, to optimize the testing process test cases should be distinguished based on their properties, such as their dependencies and similarities. Knowing the mentioned properties at an early stage of the testing process can be utilized for several test optimization purposes, such as test case selection, prioritization, scheduling,and also parallel test execution. In this paper, we apply, evaluate, and compare the performance of two deep learning algorithmsto detect the similarities between manual integration test cases. The feasibility of the mentioned algorithms is later examined in a Telecom domain by analyzing the test specifications of five different products in the product development unit at Ericsson AB in Sweden. The empirical evaluation indicates that utilizing deep learning algorithms for finding the similarities between manual integration test cases can lead to outstanding results.

    Ladda ner fulltext (pdf)
    Performance Comparison of Two Deep Learning Algorithms in Detecting Similarities Between Manual Integration Test Cases
  • 40.
    Liao, Qianfang
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Sun, Da
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Andreasson, Henrik
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Point Set Registration for 3D Range Scans Using Fuzzy Cluster-based Metric and Efficient Global Optimization2021Ingår i: IEEE Transactions on Pattern Analysis and Machine Intelligence, ISSN 0162-8828, E-ISSN 1939-3539, Vol. 43, nr 9, s. 3229-3246Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study presents a new point set registration method to align 3D range scans. In our method, fuzzy clusters are utilized to represent a scan, and the registration of two given scans is realized by minimizing a fuzzy weighted sum of the distances between their fuzzy cluster centers. This fuzzy cluster-based metric has a broad basin of convergence and is robust to noise. Moreover, this metric provides analytic gradients, allowing standard gradient-based algorithms to be applied for optimization. Based on this metric, the outlier issues are addressed. In addition, for the first time in rigid point set registration, a registration quality assessment in the absence of ground truth is provided. Furthermore, given specified rotation and translation spaces, we derive the upper and lower bounds of the fuzzy cluster-based metric and develop a branch-and-bound (BnB)-based optimization scheme, which can globally minimize the metric regardless of the initialization. This optimization scheme is performed in an efficient coarse-to-fine fashion: First, fuzzy clustering is applied to describe each of the two given scans by a small number of fuzzy clusters. Then, a global search, which integrates BnB and gradient-based algorithms, is implemented to achieve a coarse alignment for the two scans. During the global search, the registration quality assessment offers a beneficial stop criterion to detect whether a good result is obtained. Afterwards, a relatively large number of points of the two scans are directly taken as the fuzzy cluster centers, and then, the coarse solution is refined to be an exact alignment using the gradient-based local convergence. Compared to existing counterparts, this optimization scheme makes a large improvementin terms of robustness and efficiency by virtue of the fuzzy cluster-based metric and the registration quality assessment. In the experiments, the registration results of several 3D range scan pairs demonstrate the accuracy and effectiveness of the proposed method, as well as its superiority to state-of-the-art registration approaches.

    Ladda ner fulltext (pdf)
    Point Set Registration for 3D Range Scans Using Fuzzy Cluster-based Metric and Efficient Global Optimization
  • 41.
    Lopez-Paredes, Adolfo
    et al.
    INSISOC, Universidad de Valladolid, Escuela de Ingenierias Industriales Paseo del Cauce, Valladolid, Spain.
    Edmonds, Bruce
    Centre for Policy Modelling, Manchester Metropolitan University, Manchester, United Kingdom.
    Klügl, Franziska
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Special issue: Agent based simulation of complex social systems2012Ingår i: Simulation (San Diego, Calif.), ISSN 0037-5497, E-ISSN 1741-3133, Vol. 88, nr 1, s. 4-6Artikel i tidskrift (Refereegranskat)
  • 42.
    Loughlin, Santiago Mc
    et al.
    Anesthesia Department, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
    Alvarez, Adrian
    Anesthesia Department, Hospital Italiano de Buenos Aires. Buenos Aires, Argentina.
    Falcão, Luiz Fernando Dos Reis
    Federal University of São Paulo, São Paulo, Brazil.
    Ljungqvist, Olle
    Örebro universitet, Institutionen för medicinska vetenskaper.
    The History of ERAS (Enhanced Recovery After Surgery) Society and its development in Latin America2020Ingår i: Revista do Colégio Brasileiro de Cirurgiões, ISSN 0100-6991, E-ISSN 1809-4546, Vol. 47, artikel-id e20202525Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The shortage of hospital beds and changes in the payment model have promoted an increased attention and financing of programs that focus on perioperative care efficiency in. Latin America. In this paper, Enhanced Recovery After Surgery (ERAS) programs developed by the ERAS® Society will be discussed. The implementation and use of ERAS®Society Guidelines consistently demonstrated a reduction in postoperative complications, hospital stay and costs. In the current paper, the definition of ERAS programs, their core elements, and the results of their implementation and regional developments are presented with special focus on Latin America.

  • 43.
    Lowry, Stephanie
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Similarity criteria: evaluating perceptual change for visual localization2019Ingår i: 2019 European Conference on Mobile Robots (ECMR), IEEE, 2019, artikel-id 8870962Konferensbidrag (Refereegranskat)
    Abstract [en]

    Visual localization systems may operate in environments that exhibit considerable perceptual change. This paper proposes a method of evaluating the degree of appearance change using a similarity criteria based on comparing the subspaces spanned by the principal components of the observed image descriptors. We propose two criteria - θmin measures the minimum angle between subspaces and Stotal measures the total similarity between the subspaces. These criteria are introspective - they evaluate the performance of the image descriptor using nothing more than the image descriptor itself. Furthermore, we demonstrate that these similarity criteria reflect the ability of the image descriptor to perform visual localization successfully, thus allowing a measure of quality control on the localization output.

    Ladda ner fulltext (pdf)
    Similarity criteria: Evaluating perceptual change for visual localization
  • 44.
    Lunardini, Francesca
    et al.
    Politecnico Di Milano, Milan, Italy.
    Luperto, Matteo
    University of Milan, Milan, Italy.
    Romeo, Marta
    University of Manchester, Manchester, UK.
    Renoux, Jennifer
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Basilico, Nicola
    University of Milan, Milan, Italy.
    Krpič, Andrej
    Smart Com, Ljubljana, Slovenia.
    Borghese, Nunzio Alberto
    University of Milan, Milan, Italy.
    Ferrante, Simona
    Politecnico di Milano, Milan, Italy.
    The MOVECARE project: Home-based monitoring of frailty2019Ingår i: 2019 IEEE EMBS International Conference on Biomedical & Health Informatics (BHI): Proceedings, IEEE, 2019, artikel-id 8834482Konferensbidrag (Refereegranskat)
    Abstract [en]

    Concerning frailty, the use of home-based technology able to continuously and transparently monitor the independent elder may represent a useful tool to support the traditional geriatric assessment in the identification of elderly people at risk of frailty, with the final aim of guiding the development of early preventive interventions. To this aim, the European MoveCare project develops an ICT platform to support the independent living of the elder at home. Here, we describe how home-based monitoring of frailty is addressed within MoveCare, specifically for the five Fried criteria. The platform leverages a net of heterogeneous sensors a service robot, and the use of gamification to achieve ecological monitoring of frailty through quantitative measurements transparently recorded during common daily-life activities. The indicators collected over time are fed to the reasoning entity of the platform to provide informal caregivers with relevant information on the elder's status.

  • 45.
    Luperto, Matteo
    et al.
    Applied Intelligent System Lab, Department of Computer Science, University of Milan, Milano, Italy.
    Monroy, Javier
    Machine Perception and Intelligent Robotics Group (MAPIR), Department of System Engineering and Automation, University of Malaga, and Instituto de Investigación Biomédica de Málaga-IBIMA, Malaga, Spain.
    Renoux, Jennifer
    Örebro universitet, Institutionen för naturvetenskap och teknik. Machine Perception and Interaction Lab.
    Lunardini, Francesca
    NearLab, Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milano, Italy.
    Basilico, Nicola
    Applied Intelligent System Lab, Department of Computer Science, University of Milan, Milano, Italy.
    Bulgheroni, Maria
    AB.Acus SRL, Milan, Italy.
    Cangelosi, Angelo
    University of Manchester, Manchester, UK.
    Cesari, Matteo
    IRCCS Istituti Clinici Scientifici Maugeri, University of Milan, Milan, Italy.
    Cid, Manuel
    Junta de Extremadura, Merida, Spain.
    Ianes, Aladar
    Korian, Milan, Italy.
    Gonzalez-Jimenez, Javier
    Machine Perception and Intelligent Robotics Group (MAPIR), Department of System Engineering and Automation, University of Malaga, and Instituto de Investigación Biomédica de Málaga-IBIMA, Malaga, Spain.
    Kounoudes, Anastasis
    SignalGeneriX, Limassol, Cyprus.
    Mari, David
    EURECAT, Barcelona, Spain.
    Prisacariu, Victor
    University of Oxford, Oxford, UK.
    Savanovic, Arso
    Smart Com, Ljubjana, Slovenia.
    Ferrante, Simona
    NearLab, Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milano, Italy.
    Borghese, N. Alberto
    Applied Intelligent System Lab, Department of Computer Science, University of Milan, Milano, Italy.
    Integrating Social Assistive Robots, IoT, Virtual Communities and Smart Objects to Assist at-Home Independently Living Elders: the MoveCare Project2023Ingår i: International Journal of Social Robotics, ISSN 1875-4791, E-ISSN 1875-4805, Vol. 15, nr 3, s. 517-545Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The integration of Ambient Assisted Living (AAL) frameworks with Socially Assistive Robots (SARs) has proven useful for monitoring and assisting older adults in their own home. However, the difficulties associated with long-term deployments in real-world complex environments are still highly under-explored. In this work, we first present the MoveCare system, an unobtrusive platform that, through the integration of a SAR into an AAL framework, aimed to monitor, assist and provide social, cognitive, and physical stimulation in the own houses of elders living alone and at risk of falling into frailty. We then focus on the evaluation and analysis of a long-term pilot campaign of more than 300 weeks of usages. We evaluated the system's acceptability and feasibility through various questionnaires and empirically assessed the impact of the presence of an assistive robot by deploying the system with and without it. Our results provide strong empirical evidence that Socially Assistive Robots integrated with monitoring and stimulation platforms can be successfully used for long-term support to older adults. We describe how the robot's presence significantly incentivised the use of the system, but slightly lowered the system's overall acceptability. Finally, we emphasise that real-world long-term deployment of SARs introduces a significant technical, organisational, and logistical overhead that should not be neglected nor underestimated in the pursuit of long-term robust systems. We hope that the findings and lessons learned from our work can bring value towards future long-term real-world and widespread use of SARs.

  • 46.
    Memedi, Mevludin
    et al.
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    Aghanavesi, Somayeh
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    Westin, Jerker
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    A method for measuring Parkinson's disease related temporal irregularity in spiral drawings2016Ingår i: 2016 IEEE International Conference on Biomedical and Health Informatics, New York: Institute of Electrical and Electronics Engineers (IEEE), 2016, s. 410-413Konferensbidrag (Refereegranskat)
    Abstract [en]

    The objective of this paper was to develop and evaluate clinimetric properties of a method for measuring Parkinson's disease (PD)-related temporal irregularities using digital spiral analysis. In total, 108 (98 patients in different stages of PD and 10 healthy elderly subjects) performed repeated spiral drawing tasks in their home environments using a touch screen device. A score was developed for representing the amount of temporal irregularity during spiral drawing tasks, using Approximate Entropy (ApEn) technique. In addition, two previously published spiral scoring methods were adapted and their scores were analyzed. The mean temporal irregularity score differed significantly between healthy elderly subjects and advanced PD patients (P<0.005). The ApEn-based method had a better responsiveness and test-retest reliability when compared to the other two methods. In contrast to the other methods, the mean scores of the ApEn-based method improved significantly during a 3 year clinical study, indicating a possible impact of pathological basal ganglia oscillations in temporal control during spiral drawing tasks. In conclusion, the ApEn-based method could be used for differentiating between patients in different stages of PD and healthy subjects. The responsiveness and test-retest reliability were good for the ApEn-based method indicating that this method is useful for measuring upper limb temporal irregularity at a micro-level.

  • 47.
    NAKHOSTIN, SINA
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Toward Simulation of Violin Sound Based on BowingGestures2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This Master’s thesis work presents an algorithmic approach for automatic synthesis

    of the violin’s instrumental gesture controls. Focusing on

    ” Détaché”,

    as a sustained bow motion technique, this work aims to give an instrumental

    gesture model generator (a physical performer model) to learn an appropriate

    representative function based on a group of already available contours that

    belong to different performances of the same bowing technique. Contours are

    main physical parameters of bowing which can be used as inputs of a physical

    sound model, i.e virtual violin, in order to produce the expected sound. During

    this work the primary physical parameters are under study, In particular

    bow

    transversal velocity

    (v), bow pressing force(f) and bow-bridge distance(d).

    The result of this work then can be generalized to cover the other bowing

    techniques, in particular sustained techniques like different derivatives of

    legato. B-splines were used in order to devise a parametric, flexible and robust

    model which is capable in capturing subtle variations in the time continuum

    of input parameters. A series of test experiments has been conducted in order

    to evaluate the learned model, where people with strong background in music

    and a considerable proficiency in playing musical instruments were asked to

    evaluate the sounds produced by the synthetic model.

    The results of evaluation were to high extent satisfactory, indicating that

    the quality of the sound produced as the result of artificial gestures (outputs of

    performer model) were close enough to the sound produced by the gestures of

    experienced violin players.

    i

  • 48.
    Nemati, Farhang
    et al.
    Mälardalen Real-Time Research Centre, Mälardalen University, Västerås, Sweden.
    Behnam, Moris
    Mälardalen Real-Time Research Centre, Mälardalen University, Västerås, Sweden.
    Nolte, Thomas
    Mälardalen Real-Time Research Centre, Mälardalen University, Västerås, Sweden.
    An Investigation of Synchronization under Multiprocessors Hierarchical Scheduling2009Ingår i: Proceedings of the Work-In-Progress (WIP) session of the 21st Euromicro Conference on Real-Time Systems (ECRTS'09), 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the multi-core and multiprocessor research community, considerable work has been done on real-time multiprocessor scheduling algorithms where it is assumed the tasks are independent. However in practice a typical real-time system includes tasks that share resources. On the other hand, synchronization in the multiprocessor context has not received enough attention.

    In this paper we propose an extension to multiprocessor hierarchical scheduling to support resource sharing. We extend the scheduling framework with an existing synchronization protocol for global scheduling in multi-core systems.

  • 49.
    Nemati, Farhang
    et al.
    Mälardalen Real-Time Research Centre, Mälardalen University, Sweden.
    Inam, Rafia
    Mälardalen Real-Time Research Centre, Mälardalen University, Sweden.
    Nolte, Thomas
    Mälardalen Real-Time Research Centre, Mälardalen University, Sweden.
    Sjödin, Mikael
    M ̈alardalen Real-Time Research Centre, Mälardalen University, Sweden.
    Towards Resource Sharing by Message Passing among Real-Time Components on Multi-cores2011Ingår i: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA 2011 / [ed] Mammeri, Z, IEEE, 2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we propose a message passing synchronization protocol for resource sharing among real-time applications on multi-core platforms where each application is allocated on a cluster of cores. In this protocol the resources that are only used within an application (local resources) are handled by shared memory synchronization while the resources shared cross applications (global resources) are accessed by means of message passing. In our protocol the global resources are safely accessed without requiring to lock the resources explicitly. The goal is to avoid resource locking using shared memory, since accessing shared memory in multi-cores is very time consuming, whereas message passing has the potential to be much more efficient in systems with deep memory hierarchies.

  • 50.
    Nemati, Farhang
    et al.
    Mälardalen Real-Time Research Centre, Mälardalen University, Västerås, Sweden.
    Nolte, Thomas
    Mälardalen Real-Time Research Centre, Mälardalen University, Västerås, Sweden.
    Resource Hold Times under Multiprocessor Static-Priority Global Scheduling2011Ingår i: 2011 IEEE 17th International Conference on Embedded and Real-Time Computing Systems and Applications. Volume 1: Proceedings, IEEE Computer Society , 2011, s. 197-206Konferensbidrag (Refereegranskat)
    Abstract [en]

    Recently there has been a lot of interest in coexisting of multiple independently-developed real-time applications on a shared open platform. On the other hand, emerging of multi-core platforms and the performance and possibilities they offer has attracted a lot of attention in multiprocessor real-time analysis, protocols and techniques. Co-executing independently- developedreal-time applications on a shared multiprocessor system, where each application executes on a dedicated sub set of processors, requires to overcome the problem of handling mutually exclusive shared resources among those applications. To handle resource sharing, it is important to determine the Resource Hold Time (RHT), i.e., the maximum duration of time that an application locks a shared resource.

    In this paper, we study resource hold times under multiprocessor static-priority global scheduling. We present how to compute RHT's for each resource in an application. We also show how to decrease the RHT's without compromising the schedulability of the application. We show that decreasing all RHT's for all shared resources is a multiobjective optimization problem and there can exist multiple Paretooptimal solutions.

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