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  • 1.
    Abbas, Asad
    et al.
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Faiz, Ali
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Reasons for the failure of government IT projects in Pakistan: A Contemporary Study2013Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
  • 2.
    Abbas, Asad
    et al.
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Faiz, Ali
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Usefulness of Digital and Traditional Library in Higher Education2012Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 3.
    Abbay, Kissery
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    Gender Vis-à-vis Swedish Municipal Web sites2010Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 4.
    Abdul Khaliq, Ali
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Pecora, Federico
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Point-to-point safe navigation of a mobile robot using stigmergy and RFID technology2016Inngår i: 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Institute of Electrical and Electronics Engineers (IEEE), 2016, s. 1497-1504, artikkel-id 7759243Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Reliable autonomous navigation is still a challenging problem for robots with simple and inexpensive hardware. A key difficulty is the need to maintain an internal map of the environment and an accurate estimate of the robot’s position in this map. Recently, a stigmergic approach has been proposed in which a navigation map is stored into the environment, on a grid of RFID tags, and robots use it to optimally reach predefined goal points without the need for internal maps. While effective,this approach is limited to a predefined set of goal points. In this paper, we extend this approach to enable robots to travel to any point on the RFID floor, even if it was not previously identified as a goal location, as well as to keep a safe distance from any given critical location. Our approach produces safe, repeatable and quasi-optimal trajectories without the use of internal maps, self localization, or path planning. We report experiments run in a real apartment equipped with an RFID floor, in which a service robot either reaches or avoids a user who wears slippers equipped with an RFID tag reader.

  • 5.
    Abdulhomeed, Bashar
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Contemporary Research on e-democracy: A Literature Review2013Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
  • 6.
    Ackfjärd, Rickard
    et al.
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Karlsson, Mattias
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Förslag till ett nytt ramverk för utvärdering och utveckling av ARP-poisoning-skydd2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 7.
    Adolfsson, Chandra
    et al.
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    Håkansson, Alexandra
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    En studie av sambandet mellan kvarstående bias och kostnad vid selektiv granskning i undersökningen Kortperiodisk Sysselsättningsstatistik: Analys av parameterval i verktyget Selekt2009Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Det har pågått ett intensivt utvecklingsarbete på Statistiska Centralbyrån (SCB) under de senaste åren i syfte att standardisera och effektivisera statistikproduktionsprocessen. I detta utvecklingsarbete har fokus främst riktats mot processerna insamling och granskning. Ett flertal studier har visat att det finns potential att reducera granskningens omfattning samtidigt som den övergripande kvaliteten i undersökningarna bibehålls. För att uppnå detta krävs att nya arbetssätt, metoder och verktyg utvecklas och implementeras.

    Den traditionella ansatsen på SCB har varit att i granskningsprocessen försöka hitta och rätta alla databearbetnings- och mätfel. Ingen skillnad har gjorts mellan stora och små fel eller om felen har någon effekt på statistiken eller inte. Detta är en ineffektiv ansats där stora resurser åtgår till att rätta fel som inte påverkar den statistiska redovisningen nämnvärt. I mer moderna ansatser betonas vikten av att hitta betydelsefulla fel som har stor påverkan på parameterskattningarna och att fel som inte ger någon påverkan bör lämnas som de är eller åtgärdas via imputering. Detta, att inte granska allt, kallas för selektiv granskning.

    SCB har beslutat att införa metoden selektiv granskning med poängfunktioner. Metoden fordrar att poängberäkningar görs, dessa utförs i verktyget Selekt. Verktyget ingår i den framtida verktygslådan för granskning som är under utveckling vid SCB och är uppbyggt av ett stort antal parametrar. För att uppnå så effektiv granskning som möjligt måste de mest lämpliga parametervärdena sökas för att sedan implementeras i Selekt.

    I denna studie har ett datamaterial från undersökningen Kortperiodisk Sysselsättningsstatistik, privat sektor (KSP) använts för att studera sambanden mellan statistikens kvalitet och valet av parametrar i Selekt.  Valet av datamaterial motiveras främst av att Selekt ska implementeras i KSP under år 2010. De parametrar som har behandlats i studien kallas för KAPPA, TAU och LAMBDA samt variablerna RPB_20 och Kostnad.

    Logistisk regression har använts för att undersöka vilken påverkan parametrarna har på den bias (kallad RPB) som införs i skattningarna vid selektiv granskning. En ansats valdes där sambandet mellan responsvariabeln RPB_20 och förklaringsvariablerna KAPPA, TAU och Kostnad studerades separat för olika värden på LAMBDA.

    Vid resultatframställningen indikerades tidigt att valet av värde på LAMBDA inte verkade ha någon nämnvärd betydelse för modellen och i de fortsatta analyserna stärktes denna misstanke och kom att omfatta även KAPPA och TAU. Det var redan från början känt att Kostnad är en viktig variabel att ta hänsyn till och för att undersöka detta närmare konstruerades en modell bestående av ett fjärdegradspolynom med enbart variabeln Kostnad. Modellen lyckades fånga upp huvuddragen av variationen i RPB_20.

    Det går inte att dra generella slutsatser från den studie som här har genomförts. Resultaten visar dock att en modell utan KAPPA, TAU och LAMBDA fungerar för att beskriva variationen i RPB_20.  Valet av värden på KAPPA, TAU och LAMBDA i Selekt är av mindre betydelse. I implementeringsarbetet av Selekt i KSP rekommenderas därför att, förutom RPB, fokusera på variabeln Kostnad för att hitta den mest lämpliga kombinationen av parameterinställningar.

  • 8.
    Adolfsson, Daniel
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Lowry, Stephanie
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Magnusson, Martin
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Andreasson, Henrik
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    A Submap per Perspective: Selecting Subsets for SuPer Mapping that Afford Superior Localization Quality2019Inngår i: 2019 European Conference on Mobile Robots (ECMR), IEEE, 2019Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper targets high-precision robot localization. We address a general problem for voxel-based map representations that the expressiveness of the map is fundamentally limited by the resolution since integration of measurements taken from different perspectives introduces imprecisions, and thus reduces localization accuracy.We propose SuPer maps that contain one Submap per Perspective representing a particular view of the environment. For localization, a robot then selects the submap that best explains the environment from its perspective. We propose SuPer mapping as an offline refinement step between initial SLAM and deploying autonomous robots for navigation. We evaluate the proposed method on simulated and real-world data that represent an important use case of an industrial scenario with high accuracy requirements in an repetitive environment. Our results demonstrate a significantly improved localization accuracy, up to 46% better compared to localization in global maps, and up to 25% better compared to alternative submapping approaches.

  • 9.
    Afshar, Sara
    et al.
    Mälardalen University, Västerås, Sweden.
    Nemati, Farhang
    Mälardalen University, Västerås, Sweden.
    Nolte, Thomas
    Mälardalen University, Västerås, Sweden.
    Resource Sharing under Multiprocessor Semi-Partitioned Scheduling2012Inngår i: 2012 IEEE International Conference on Embedded and Real-Time Computing Systems and Applications: Proceedings, IEEE, 2012, s. 290-299Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Semi-partitioned scheduling has become the subject of recent interest for multiprocessors due to better utilization results, compared to conventional global and partitioned scheduling algorithms. Under semi-partitioned scheduling, a major group of tasks are assigned to fixed processors while a low number of tasks are allocated to more than one processor. Various task assigning techniques have recently been proposed in a semi-partitioned environment. However, a synchronization mechanism for resource sharing among tasks in semi-partitioned scheduling has not yet been investigated. In this paper we propose and evaluate two methods for handling resource sharing under semi-partitioned scheduling in multiprocessor platforms. The main challenge addressed in this paper is to serve the resource requests of tasks that are assigned to different processors.

  • 10.
    Afshar, Sara
    et al.
    Mälardalen University, Västerås, Sweden.
    Nemati, Farhang
    Mälardalen University, Västerås, Sweden.
    Nolte, Thomas
    Mälardalen University, Västerås, Sweden.
    Towards Resource Sharing under Multiprocessor Semi-Partitioned Scheduling2012Inngår i: 7th IEEE International Symposium on Industrial Embedded Systems (SIES'12): Conference Proceedings, IEEE, 2012, s. 315-318Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Semi-partitioned scheduling has been the subject of recent interest, compared with conventional global and partitioned scheduling algorithms for multiprocessors, due to better utilization results. In semi-partitioned scheduling most tasks are assigned to fixed processors while a low number of tasks are split up and allocated to different processors. Various techniques have recently been proposed to assign tasks in a semi-partitioned environment. However, an appropriate resource sharing mechanism for handling the resource requests between tasks in semi-partitioned scheduling has not yet been investigated. In this paper we propose two methods for handling resource sharing under semi-partitioned scheduling in multiprocessor platforms. The main challenge is to handle the resource requests of tasks that are split over multiple processors.

  • 11.
    AGALOMBA, CHRISTINE AFANDI
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Factors contributing to failure of egovernment projects in developing countries: a literature review2012Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
  • 12.
    Agalomba, Christine Afandi
    et al.
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    Bakibinga, Stella
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    A Review of Telecentre Literature: Sustainability, Impact and Best practices2010Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 13.
    Aghanavesi, Somayeh
    et al.
    Department of Computer Engineering, Dalarna University, Borlänge, Sweden.
    Bergquist, Filip
    Department of Pharmacology, Institute of Neuroscience and Physiology, Gothenburg University, Gothenburg, Sweden.
    Nyholm, Dag
    Department of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Senek, Marina
    Department of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Memedi, Mevludin
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Motion sensor-based assessment of Parkinson's disease motor symptoms during leg agility tests: results from levodopa challenge2020Inngår i: IEEE journal of biomedical and health informatics, ISSN 2168-2194, E-ISSN 2168-2208, Vol. 24, nr 1, s. 111-118Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Parkinson's disease (PD) is a degenerative, progressive disorder of the central nervous system that mainly affects motor control. The aim of this study was to develop data-driven methods and test their clinimetric properties to detect and quantify PD motor states using motion sensor data from leg agility tests. Nineteen PD patients were recruited in a levodopa single dose challenge study. PD patients performed leg agility tasks while wearing motion sensors on their lower extremities. Clinical evaluation of video recordings was performed by three movement disorder specialists who used four items from the motor section of the Unified PD Rating Scale (UPDRS), the treatment response scale (TRS) and a dyskinesia score. Using the sensor data, spatiotemporal features were calculated and relevant features were selected by feature selection. Machine learning methods like support vector machines (SVM), decision trees and linear regression, using 10-fold cross validation were trained to predict motor states of the patients. SVM showed the best convergence validity with correlation coefficients of 0.81 to TRS, 0.83 to UPDRS #31 (body bradykinesia and hypokinesia), 0.78 to SUMUPDRS (the sum of the UPDRS items: #26-leg agility, #27-arising from chair and #29-gait), and 0.67 to dyskinesia. Additionally, the SVM-based scores had similar test-retest reliability in relation to clinical ratings. The SVM-based scores were less responsive to treatment effects than the clinical scores, particularly with regards to dyskinesia. In conclusion, the results from this study indicate that using motion sensors during leg agility tests may lead to valid and reliable objective measures of PD motor symptoms.

  • 14.
    Aghanavesi, Somayeh
    et al.
    Computer Engineering, School of Technology and Business Studies, Borlänge, Dalarna University, Sweden.
    Bergquist, Filip
    Dept. of Pharmacology, University of Gothenburg, Gothenburg, Sweden.
    Nyholm, Dag
    Dept. of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Senek, Marina
    Dept. of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Memedi, Mevludin
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Objective assessment of Parkinson’s disease motor symptoms during leg agility test using motion sensors2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Title: Objective assessment of Parkinson’s disease motor symptoms during leg agility test using motion sensors

    Objective: To develop and evaluate machine learning methods for assessment of Parkinson’s disease (PD) motor symptoms using leg agility (LA) data collected with motion sensors during a single dose experiment.

    Background: Nineteen advanced PD patients (Gender: 14 males and 5 females, mean age: 71.4, mean years with PD: 9.7, mean years with levodopa: 9.5) were recruited in a single center, open label, single dose clinical trial in Sweden [1].

    Methods: The patients performed up to 15 LA tasks while wearing motions sensors on their foot ankle. They performed tests at pre-defined time points starting from baseline, at the time they received a morning dose (150% of their levodopa equivalent morning dose), and at follow-up time points until the medication wore off. The patients were video recorded while performing the motor tasks. and three movement disorder experts rated the observed motor symptoms using 4 items from the Unified PD Rating Scale (UPDRS) motor section including UPDRS #26 (leg agility), UPDRS #27 (Arising from chair), UPDRS #29 (Gait), UPDRS #31 (Body Bradykinesia and Hypokinesia), and dyskinesia scale. In addition, they rated the overall mobility of the patients using Treatment Response Scale (TRS), ranging from -3 (very off) to 3 (very dyskinetic). Sensors data were processed and their quantitative measures were used to develop machine learning methods, which mapped them to the mean ratings of the three raters. The quality of measurements of the machine learning methods was assessed by convergence validity, test-retest reliability and sensitivity to treatment.

    Results: Results from the 10-fold cross validation showed good convergent validity of the machine learning methods (Support Vector Machines, SVM) with correlation coefficients of 0.81 for TRS, 0.78 for UPDRS #26, 0.69 for UPDRS #27, 0.78 for UPDRS #29, 0.83 for UPDRS #31, and 0.67 for dyskinesia scale (P<0.001). There were good correlations between scores produced by the methods during the first (baseline) and second tests with coefficients ranging from 0.58 to 0.96, indicating good test-retest reliability. The machine learning methods had lower sensitivity than mean clinical ratings (Figure. 1).

    Conclusions: The presented methodology was able to assess motor symptoms in PD well, comparable to movement disorder experts. The leg agility test did not reflect treatment related changes.

  • 15.
    Aghanavesi, Somayeh
    et al.
    Computer Engineering, School of Technology and Business Studies, Dalarna University, Borlänge, Sweden.
    Filip, Bergquist
    Dept. of Pharmacology, University of Gothenburg, Gothenbrug, Sweden.
    Nyholm, Dag
    Dept. of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Senek, Marina
    Dept. of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Memedi, Mevludin
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Feasibility of a multi-sensor data fusion method for assessment of Parkinson’s disease motor symptoms2018Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Title: Feasibility of a multi-sensor data fusion method for assessment of Parkinson’s disease motor symptoms

    Objective: To assess the feasibility of measuring Parkinson’s disease (PD) motor symptoms with a multi-sensor data fusion method. More specifically, the aim is to assess validity, reliability and sensitivity to treatment of the methods.

    Background: Data from 19 advanced PD patients (Gender: 14 males and 5 females, mean age: 71.4, mean years with PD: 9.7, mean years with levodopa: 9.5) were collected in a single center, open label, single dose clinical trial in Sweden [1].

    Methods: The patients performed leg agility and 2-5 meter straight walking tests while wearing motion sensors on their limbs. They performed the tests at baseline, at the time they received the morning dose, and at pre-specified time points until the medication wore off. While performing the tests the patients were video recorded. The videos were observed by three movement disorder specialists who rated the symptoms using a treatment response scale (TRS), ranging from -3 (very off) to 3 (very dyskinetic). The sensor data consisted of lower limb data during leg agility, upper limb data during walking, and lower limb data during walking. Time series analysis was performed on the raw sensor data extracted from 17 patients to derive a set of quantitative measures, which were then used during machine learning to be mapped to mean ratings of the three raters on the TRS scale. Combinations of data were tested during the machine learning procedure.

    Results: Using data from both tests, the Support Vector Machines (SVM) could predict the motor states of the patients on the TRS scale with a good agreement in relation to the mean ratings of the three raters (correlation coefficient = 0.92, root mean square error = 0.42, p<0.001). Additionally, there was good test-retest reliability of the SVM scores during baseline and second tests with intraclass-correlation coefficient of 0.84. Sensitivity to treatment for SVM was good (Figure 1), indicating its ability to detect changes in motor symptoms. The upper limb data during walking was more informative than lower limb data during walking since SVMs had higher correlation coefficient to mean ratings.  

    Conclusions: The methodology demonstrates good validity, reliability, and sensitivity to treatment. This indicates that it could be useful for individualized optimization of treatments among PD patients, leading to an improvement in health-related quality of life.

  • 16.
    Aghanavesi, Somayeh
    et al.
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    Memedi, Mevludin
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Dougherty, Mark
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    Nyholm, Dag
    Department of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Westin, Jerker
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    Verification of a Method for Measuring Parkinson’s Disease Related Temporal Irregularity in Spiral Drawings2017Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 17, nr 10, artikkel-id 2341Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Parkinson’s disease (PD) is a progressive movement disorder caused by the death of dopamine-producing cells in the midbrain. There is a need for frequent symptom assessment, since the treatment needs to be individualized as the disease progresses. The aim of this paper was to verify and further investigate the clinimetric properties of an entropy-based method for measuring PD-related upper limb temporal irregularities during spiral drawing tasks. More specifically, properties of a temporal irregularity score (TIS) for patients at different stages of PD, and medication time points were investigated. Nineteen PD patients and 22 healthy controls performed repeated spiral drawing tasks on a smartphone. Patients performed the tests before a single levodopa dose and at specific time intervals after the dose was given. Three movement disorder specialists rated videos of the patients based on the unified PD rating scale (UPDRS) and the Dyskinesia scale. Differences in mean TIS between the groups of patients and healthy subjects were assessed. Test-retest reliability of the TIS was measured. The ability of TIS to detect changes from baseline (before medication) to later time points was investigated. Correlations between TIS and clinical rating scores were assessed. The mean TIS was significantly different between healthy subjects and patients in advanced groups (p-value = 0.02). Test-retest reliability of TIS was good with Intra-class Correlation Coefficient of 0.81. When assessing changes in relation to treatment, TIS contained some information to capture changes from Off to On and wearing off effects. However, the correlations between TIS and clinical scores (UPDRS and Dyskinesia) were weak. TIS was able to differentiate spiral drawings drawn by patients in an advanced stage from those drawn by healthy subjects, and TIS had good test-retest reliability. TIS was somewhat responsive to single-dose levodopa treatment. Since TIS is an upper limb high-frequency-based measure, it cannot be detected during clinical assessment.

  • 17.
    Aghanavesi, Somayeh
    et al.
    Computer Engineering, School of Technology and Business Studies, Dalarna University, Borlänge, Sweden.
    Memedi, Mevludin
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Westin, Jerker
    Computer Engineering, School of Technology and Business Studies, Dalarna University, Borlänge, Sweden.
    Measuring temporal irregularity in spiral drawings of patients with Parkinson’s disease2017Inngår i: Abstracts of the 21st International Congress of Parkinson's Disease and Movement Disorders, John Wiley & Sons, 2017, Vol. 32, s. s252-s252, artikkel-id 654Konferansepaper (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    Objective: The aim of this work is to evaluate clinimetric properties of a method for measuring Parkinson’s disease (PD) upper limb temporal irregularities during spiral drawing tasks.

    Background: Basal ganglia fluctuations of PD patients are associated with motor symptoms and relating them to objective sensor-based measures may facilitate the assessment of temporal irregularities, which could be difficult to be assessed visually. The present study investigated the upper limb temporal irregularity of patients at different stages of PD and medication time points.

    Methods: Nineteen PD patients and 22 healthy controls performed repeated spiral drawing tasks on a smartphone. Patients performed the tests before a single levodopa dose and at specific time intervals after the dose was given. Three movement disorder specialists rated the videos of patients' performance according to six items of UPDRS-III, dyskinesia (Dys), and Treatment Response Scale (TRS). A temporal irregularity score (TIS) was developed using approximate entropy (ApEn) method. Differences in mean TIS between two groups of patients and healthy subjects, and also across four subject groups: early, intermediate, advanced patients and, healthy subjects were assessed. The relative ability of TIS to detect changes from baseline (no medication) to later time points when patients were on medication was assessed. Correlations between TIS and clinical rating scales were assessed by Pearson correlation coefficients and test-retest reliability of TIS was measured by intra-class correlation coefficients (ICC).

    Results: The mean TIS was significantly different between healthy subjects and patients (P<0.0001). When assessing the changes in relation to treatment, clinical-based scores (TRS and Dys) had better responsiveness than TIS. However, the TIS was able to capture changes from Off to On, and the wearing off effects. Correlations between TIS and clinical scales were low indicating poor validity. Test-retest reliability correlation coefficient of the mean TIS was good (ICC=0.67).

    Conclusions: Our study found that TIS was able to differentiate spiral drawings drawn by patients from those drawn by healthy subjects. In addition, TIS could capture changes throughout the levodopa cycle.TIS was weakly correlated to clinical ratings indicating that TIS measures high frequency upper limb temporal irregularities that could be difficult to be detected during clinical observations.

  • 18.
    Aghanavesi, Somayeh
    et al.
    Computer Engineering, School of Technology and Business Studies, Dalarna University, Falun, Sweden.
    Nyholm, Dag
    Dept. of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Senek, Marina
    Dept. of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Bergquist, Filip
    Dept. of Pharmacology, University of Gothenburg, Gothenburg, Sweden.
    Memedi, Mevludin
    Örebro universitet, Handelshögskolan vid Örebro Universitet. Computer Engineering, School of Technology and Business Studies, Dalarna University, Falun, Sweden.
    A smartphone-based system to quantify dexterity in Parkinson's disease patients2017Inngår i: Informatics in Medicine Unlocked, ISSN 2352-9148, Vol. 9, s. 11-17Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Objectives

    The aim of this paper is to investigate whether a smartphone-based system can be used to quantify dexterity in Parkinson's disease (PD). More specifically, the aim was to develop data-driven methods to quantify and characterize dexterity in PD.

    Methods

    Nineteen advanced PD patients and 22 healthy controls participated in a clinical trial in Uppsala, Sweden. The subjects were asked to perform tapping and spiral drawing tests using a smartphone. Patients performed the tests before, and at pre-specified time points after they received 150% of their usual levodopa morning dose. Patients were video recorded and their motor symptoms were assessed by three movement disorder specialists using three Unified PD Rating Scale (UPDRS) motor items from part III, the dyskinesia scoring and the treatment response scale (TRS). The raw tapping and spiral data were processed and analyzed with time series analysis techniques to extract 37 spatiotemporal features. For each of the five scales, separate machine learning models were built and tested by using principal components of the features as predictors and mean ratings of the three specialists as target variables.

    Results

    There were weak to moderate correlations between smartphone-based scores and mean ratings of UPDRS item #23 (0.52; finger tapping), UPDRS #25 (0.47; rapid alternating movements of hands), UPDRS #31 (0.57; body bradykinesia and hypokinesia), sum of the three UPDRS items (0.46), dyskinesia (0.64), and TRS (0.59). When assessing the test-retest reliability of the scores it was found that, in general, the clinical scores had better test-retest reliability than the smartphone-based scores. Only the smartphone-based predicted scores on the TRS and dyskinesia scales had good repeatability with intra-class correlation coefficients of 0.51 and 0.84, respectively. Clinician-based scores had higher effect sizes than smartphone-based scores indicating a better responsiveness in detecting changes in relation to treatment interventions. However, the first principal component of the 37 features was able to capture changes throughout the levodopa cycle and had trends similar to the clinical TRS and dyskinesia scales. Smartphone-based scores differed significantly between patients and healthy controls.

    Conclusions

    Quantifying PD motor symptoms via instrumented, dexterity tests employed in a smartphone is feasible and data from such tests can also be used for measuring treatment-related changes in patients.

  • 19.
    Aghanavesi, Somayeh
    et al.
    Department of Computer Engineering, Dalarna University, Falun, Sweden.
    Westin, Jerker
    Department of Computer Engineering, Dalarna University, Falun, Sweden.
    Bergquist, Filip
    Department of Pharmacology at Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.
    Nyholm, Dag
    Department of Neuroscience, Neurology at Uppsala University, Uppsala, Sweden.
    Askmark, Håkan
    Department of Neuroscience, Neurology at Uppsala University, Uppsala, Sweden.
    Aquilonius, Sten Magnus
    Department of Neuroscience, Neurology at Uppsala University, Uppsala, Sweden.
    Constantinescu, Radu
    Department of Clinical Neuroscience, University of Gothenburg, Gothenburg, Sweden.
    Medvedev, Alexander
    Department of Information Technology, at Uppsala University, Uppsala, Sweden.
    Spira, Jack
    Sensidose AB, Sollentuna, Sweden.
    Ohlsson, Fredrik
    Department of Sensor Systems at Acreo Swedish ICT, Kista, Sweden.
    Thomas, Ilias
    Department of Statistics, Dalarna University, Falun, Sweden.
    Ericsson, Anders
    Department of Clinical Neuroscience and Rehabilitation, University of Gothenburg, Gothenburg, Sweden.
    Johansson Buvarp, Dongni
    Irisity AB, Gothenburg.
    Memedi, Mevludin
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    A multiple motion sensors index for motor state quantification in Parkinson's disease2020Inngår i: Computer Methods and Programs in Biomedicine, ISSN 0169-2607, E-ISSN 1872-7565Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Aim: To construct a Treatment Response Index from Multiple Sensors (TRIMS) for quantification of motor state in patients with Parkinson's disease (PD) during a single levodopa dose. Another aim was to compare TRIMS to sensor indexes derived from individual motor tasks.

    Method: Nineteen PD patients performed three motor tests including leg agility, pronation-supination movement of hands, and walking in a clinic while wearing inertial measurement unit sensors on their wrists and ankles. They performed the tests repeatedly before and after taking 150% of their individual oral levodopa-carbidopa equivalent morning dose.Three neurologists blinded to treatment status, viewed patients’ videos and rated their motor symptoms, dyskinesia, overall motor state based on selected items of Unified PD Rating Scale (UPDRS) part III, Dyskinesia scale, and Treatment Response Scale (TRS). To build TRIMS, out of initially 178 extracted features from upper- and lower-limbs data, 39 features were selected by stepwise regression method and were used as input to support vector machines to be mapped to mean reference TRS scores using 10-fold cross-validation method. Test-retest reliability, responsiveness to medication, and correlation to TRS as well as other UPDRS items were evaluated for TRIMS.

    Results: The correlation of TRIMS with TRS was 0.93. TRIMS had good test-retest reliability (ICC=0.83). Responsiveness of the TRIMS to medication was good compared to TRS indicating its power in capturing the treatment effects. TRIMS was highly correlated to dyskinesia (R = 0.85), bradykinesia (R=0.84) and gait (R=0.79) UPDRS items. Correlation of sensor index from the upper-limb to TRS was 0.89.

    Conclusion: Using the fusion of upper- and lower-limbs sensor data to construct TRIMS provided accurate PD motor states estimation and responsive to treatment. In addition, quantification of upper-limb sensor data during walking test provided strong results.

  • 20.
    Agrawal, Vikas
    et al.
    IBM Research, , India.
    Archibald, Christopher
    Mississippi State University, Starkville, United States.
    Bhatt, Mehul
    University of Bremen, Bremen, Germany.
    Bui, Hung Hai
    Laboratory for Natural Language Understanding, Sunnyvale CA, United States.
    Cook, Diane J.
    Washington State University, Pullman WA, United States.
    Cortés, Juan
    University of Toulouse, Toulouse, France.
    Geib, Christopher W.
    Drexel University, Philadelphia PA, United States.
    Gogate, Vibhav
    Department of Computer Science, University of Texas, Dallas, United States.
    Guesgen, Hans W.
    Massey University, Palmerston North, New Zealand.
    Jannach, Dietmar
    Technical university Dortmund, Dortmund, Germany.
    Johanson, Michael
    University of Alberta, Edmonton, Canada.
    Kersting, Kristian
    Fraunhofer-Institut für Intelligente Analyse- und Informationssysteme (IAIS), Sankt Augustin, Germany; The University of Bonn, Bonn, Germany.
    Konidaris, George
    Massachusetts Institute of Technology (MIT), Cambridge MA, United States.
    Kotthoff, Lars
    INSIGHT Centre for Data Analytics, University College Cork, Cork, Ireland.
    Michalowski, Martin
    Adventium Labs, Minneapolis MN, United States.
    Natarajan, Sriraam
    Indiana University, Bloomington IN, United States.
    O’Sullivan, Barry
    INSIGHT Centre for Data Analytics, University College Cork, Cork, Ireland.
    Pickett, Marc
    Naval Research Laboratory, Washington DC, United States.
    Podobnik, Vedran
    Telecommunication Department of the Faculty of Electrical Engineering and Computing, University of University of Zagreb, Zagreb, Croatia.
    Poole, David
    Department of Computer Science, University of British Columbia, Vancouver, Canada.
    Shastri, Lokendra
    Infosys, , India.
    Shehu, Amarda
    George Mason University, Washington, United States.
    Sukthankar, Gita
    University of Central Florida, Orlando FL, United States.
    The AAAI-13 Conference Workshops2013Inngår i: The AI Magazine, ISSN 0738-4602, Vol. 34, nr 4, s. 108-115Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The AAAI-13 Workshop Program, a part of the 27th AAAI Conference on Artificial Intelligence, was held Sunday and Monday, July 14-15, 2013, at the Hyatt Regency Bellevue Hotel in Bellevue, Washington, USA. The program included 12 workshops covering a wide range of topics in artificial intelligence, including Activity Context-Aware System Architectures (WS-13-05); Artificial Intelligence and Robotics Methods in Computational Biology (WS-13-06); Combining Constraint Solving with Mining and Learning (WS-13-07); Computer Poker and Imperfect Information (WS-13-08); Expanding the Boundaries of Health Informatics Using Artificial Intelligence (WS-13-09); Intelligent Robotic Systems (WS-13-10); Intelligent Techniques for Web Personalization and Recommendation (WS-13-11); Learning Rich Representations from Low-Level Sensors (WS-13-12); Plan, Activity,, and Intent Recognition (WS-13-13); Space, Time, and Ambient Intelligence (WS-13-14); Trading Agent Design and Analysis (WS-13-15); and Statistical Relational Artificial Intelligence (WS-13-16)

  • 21.
    Agélii Genlott, Annika
    et al.
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Grönlund, Åke
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Closing the gaps: Improving literacy and mathematics by ict-enhanced collaboration2016Inngår i: Computers and education, ISSN 0360-1315, E-ISSN 1873-782X, Vol. 99, s. 68-80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Literacy and mathematics are necessary skills that for different reasons unfortunately not everybody acquires sufficiently. In OECD countries there is also a gender gap; boys lag behind girls in literacy but often outperform girls in mathematics (OECD, 2012). ICT (Information and communication technologies) may contribute useful tools to address both these problems but in order to effectively create better educational conditions there is yet a need to develop effective methods that combine ICT with key factors for learning. This research contributes to this by measuring effects of the “Write to Learn” (WTL) method. WTL lets children from 1st grade use several ICT tools to write texts and subsequently discuss and refine them together with classmates and teachers using digital real-time formative feedback and assessment. The central learning factor addressed, in mathematics as well as in literacy, is the written communication allowing the learners to interact with peers and teachers. WTL draws on methods from socio-cultural theory, including continuous social interaction and written real-time formative feedback among peers, using shared electronic forums for collaboration, thereby providing social meaning and increased learning of literacy and mathematics, among both boys and girls.

    The study uses quantitative methods and two control groups, one using traditional method (no ICT) and one using technology individually (without integrated social interaction and formative feedback), to compare results from 502 students in grade 3 national tests in mathematics and literacy. WTL yields by far best results; higher average score both in literacy and mathematics, smaller gender gap, and significantly better results for the under-achievers. The ITU method performs worst, which shows that ICT use must be well integrated into the pedagogy to be useful.

  • 22.
    Ahlinder, Mikael
    et al.
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    Wiklund, Martin
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    ANVÄNDBARHET OCH HANDLINGSBARHET PÅ ELEKTRONISKA B2B MARKNADSPLATSER: En fallstudie på Visma Proceedo ur leverantörens perspektiv2009Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    De elektroniska marknadsplatsernas betydelse för affärstransaktioner världen över har ökat dramatiskt de senaste åren. Allt fler företag väljer att ta med sina befintliga kundkontakter eller skapa nya via dessa marknadsplatser. Dock finns det vissa problem med dessa, ofta webbaserade system, de har inte en tillfred- ställande grad av användbarhet respektive handlingsbarhet. Syftet med vår undersökning var att beskriva vilka aspekter av de olika perspek- tiven, användbarhet samt handlingsbarhet, som kan anses vara mer betydande än andra att ta hänsyn till vid utveckling av elektroniska B2B marknadsplatser. Användbarhet är ett perspektiv som behandlar aspekter som att systemet skall vara lätt att använda, lätt att lära, subjektivt tilltalande osv. Handlingsbarhet som perspektiv tar till skillnad från användbarheten en mer kommunikativ utgångs- punkt, där systemets förmåga att fungera som en kommunikativ länk i de verk- samhetshandlingar som utförs sätts i fokus. Vi har genomfört en kvalitativ fallstudie på marknadsplatsoperatören Visma Proceedo’s webbsystem Supplier Center. Datainsamling har främst skett genom telefonintervjuer med tre olika företag som använder sig av Supplier Center som lösning för deras kundkommunikation.  Vi har i våra slutsatser kommit fram till att vissa aspekter av de två perspektiven är viktigare att beakta vi utformning av ett system likt Supplier Center. Ett så- dant system skall tillgodose kraven på tydlig handlingsrepertoar, handlingstrans- parent, tydlig feedback, personifiering, känd och begriplig vokabulär, intentionellt tydligt, handlingsstödjande, minimera användarens minnesbelastning, enhetlighet, förse användaren med återkoppling, förse användaren med klart markerade funk- tioner för att avbryta dialogen, bra felmeddelanden och förhindra fel.

  • 23.
    Ahmed, Farouq
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Utökad automatisering av e-handel med shopify API2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    inträdesbarriären. För att vara relevanta måste säljare vara så effektiva som möjligt genom att använda sig av olika metoder och verktyg för att uppnå en framgångsrik och lönsam webbutik. En av metoderna som används av säljare är drop shipping som tillåter försäljning av varor utan lagerhållning. Detta sker genom att säljare köper varor från en tredje part som levererar direkt till kunden vid beställning, istället för att köpa produkterna i förväg. Detta leder till billigare samt effektivare handel för nya samt redan existerande säljare.Trots de goda möjligheterna som drop shipping erbjuder är det tidskrävande och kräver en hög nivå av noggrannhet, då säljprocessen består av upprepade manuella uppgifter. Detta är ett problem som kan hindra säljare från att utnyttja sig av drop shipping modellen. För att göra det enklare för säljare att använda sig av denna modell, kan de manuella åtgärderna skötas av ett program som gör det automatiskt.I denna rapport studeras olika mjukvaruarkitektoniska mönster för att bygga grunden av ett prototypprogram som utför de manuella åtgärderna med en tillfredsställande nivå av automation.

  • 24.
    Ahmed, Mobyen Uddin
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Banaee, Hadi
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Rafael-Palou, Xavier
    Barcelona Digital Technology Centre, Barcelona, Spain.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Intelligent Healthcare Services to Support Health Monitoring of Elderly2015Inngår i: INTERNET OF THINGS: USER-CENTRIC IOT, PT I, Springer, 2015, Vol. 150, s. 178-186Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper proposed an approach of intelligent healthcare services to support health monitoring of old people through the project named SAAPHO. Here, definition and architecture of the proposed healthcare services are presented considering six different health parameters such as: 1) physical activity, 2) blood pressure, 3) glucose, 4) medication compliance, 5) pulse monitoring and 6) weight monitoring. The outcome of the proposed services is evaluated in a case study where total 201 subjects from Spain and Slovenia are involved for user requirements analysis considering 1) end users, 2) clinicians, and 3) field study analysis perspectives. The result shows the potentiality and competence of the proposed healthcare services for the users.

  • 25.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, Västerås, Sweden.
    Fotouhi, Hossein
    Mälardalen University, Västerås, Sweden.
    Köckemann, Uwe
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Lindén, Maria
    Mälardalen University, Västerås, Sweden.
    Tomasic, Ivan
    Mälardalen University, Västerås, Sweden.
    Tsiftes, Nicolas
    RISE SICS, Stockholm, Sweden.
    Voigt, Thiemo
    RISE SICS, Stockholm, Sweden.
    Run-Time Assurance for the E-care@home System2018Inngår i: Internet of Things (IoT) Technologies for HealthCare (HealthyIoT 2017) / [ed] Ahmed, MU; Begum, S; Fasquel, JB, Springer, 2018, Vol. 225, s. 107-110Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents the design and implementation of the software for a run-time assurance infrastructure in the E-care home system. An experimental evaluation is conducted to verify that the run-time assurance infrastructure is functioning correctly, and to enable detecting performance degradation in experimental IoT network deployments within the context of E-care home.

  • 26.
    Ahmed, Mobyen Uddin
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Physical Activity Classification for Elderly based on Pulse Rate2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Physical activity is one of the key components for elderly in order to be actively ageing. However, it is difficult to differentiate and identify the body movement and actual physical activity using only accelerometer measurement. Therefore, this paper presents an application of case-based retrieval classification scheme to classify the physical activity of elderly based on pulse rate measurements. Here, case-based retrieval approach used the features extracted from both time and frequency domain. The evaluation result shows the best accuracy performance while considering the combination of time and frequency domain features. According to the evaluation result while considering the control measurements, the sensitivity, specificity and overall accuracy are achieved as 95%, 96% and 96% respectively. Considering the test dataset, the system was succeeded to identify 13 physical activities out of 16 i.e. the percentage of the correctness was 81%.

  • 27.
    Ahmed, Mobyen Uddin
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Physical activity identification using supervised machine learning and based on pulse rate2013Inngår i: International Journal of Advanced Computer Sciences and Applications, ISSN 2158-107X, E-ISSN 2156-5570, Vol. 4, nr 7, s. 210-217Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Physical activity is one of the key components for elderly in order to be actively ageing. Pulse rate is a convenient physiological parameter to identify elderly’s physical activity since it increases with activity and decreases with rest. However, analysis and classification of pulse rate is often difficult due to personal variation during activity. This paper proposed a Case-Based Reasoning (CBR) approach to identify physical activity of elderly based on pulse rate. The proposed CBR approach has been compared with the two popular classification techniques, i.e. Support Vector Machine (SVM) and Neural Network (NN). The comparison has been conducted through an empirical experimental study where three experiments with 192 pulse rate measurement data are used. The experiment result shows that the proposed CBR approach outperforms the other two methods. Finally, the CBR approach identifies physical activity of elderly 84% accurately based on pulse rate

  • 28.
    Ahmed, Rehan M.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ananiev, Anani V.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Compliant motion control for safe human robot interaction2009Inngår i: Robot motion and control 2009 / [ed] Krzysztof R. Kozłowski, Berlin: Springer , 2009, s. 265-274Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Robots have recently been foreseen to work side by side and share workspace with humans in assisting them in tasks that include physical human-robot (HR) interaction. The physical contact with human tasks under uncertainty has to be performed in a stable and safe manner [6]. However, current industrial robot manipulators are still very far from HR coexisting environments, because of their unreliable safety, rigidity and heavy structure. Besides this, the industrial norms separate the two spaces occupied by a human and a robot by means of physical fence or wall [9]. Therefore, the success of such physical HR interaction is possible if the robot is enabled to handle this interaction in a smart way to prevent injuries and damages.

  • 29.
    Ahmed, Rehan M.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Modeling of magneto rheological fluid actuator enabling safe human-robot interaction2008Inngår i: IEEE International Conference on Emerging Technologies and Factory Automation, 2008. ETFA 2008, 2008, s. 974-979Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Impedance control and compliant behavior for safe human-robot physical interaction of industrial robots normally can be achieved by using active compliance control of actuators based on various sensor data. Alternatively, passive devices allow controllable compliance motion but usually are mechanically complex. We present another approach using a novel actuation mechanism based on magneto-rheological fluid (MRF) that incorporates variable stiffness directly into the joints. In this paper, we have investigated and analyzed principle characteristics of MRF actuation mechanism and presented the analytical-model. Then we have developed the static and dynamic model based on experimental test results and have discussed three essential modes of motion needed for human-robot manipulation interactive tasks.

  • 30.
    Ahtiainen, Juhana
    et al.
    Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland.
    Stoyanov, Todor
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Saarinen, Jari
    GIM Ltd., Espoo, Finland.
    Normal Distributions Transform Traversability Maps: LIDAR-Only Approach for Traversability Mapping in Outdoor Environments2017Inngår i: Journal of Field Robotics, ISSN 1556-4959, E-ISSN 1556-4967, Vol. 34, nr 3, s. 600-621Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Safe and reliable autonomous navigation in unstructured environments remains a challenge for field robots. In particular, operating on vegetated terrain is problematic, because simple purely geometric traversability analysis methods typically classify dense foliage as nontraversable. As traversing through vegetated terrain is often possible and even preferable in some cases (e.g., to avoid executing longer paths), more complex multimodal traversability analysis methods are necessary. In this article, we propose a three-dimensional (3D) traversability mapping algorithm for outdoor environments, able to classify sparsely vegetated areas as traversable, without compromising accuracy on other terrain types. The proposed normal distributions transform traversability mapping (NDT-TM) representation exploits 3D LIDAR sensor data to incrementally expand normal distributions transform occupancy (NDT-OM) maps. In addition to geometrical information, we propose to augment the NDT-OM representation with statistical data of the permeability and reflectivity of each cell. Using these additional features, we train a support-vector machine classifier to discriminate between traversable and nondrivable areas of the NDT-TM maps. We evaluate classifier performance on a set of challenging outdoor environments and note improvements over previous purely geometrical traversability analysis approaches.

  • 31.
    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 Security2017Inngår 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. 628-637Konferansepaper (Fagfellevurdert)
    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.

  • 32.
    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 Robot2018Inngår 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. 462-471Konferansepaper (Fagfellevurdert)
    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.

  • 33.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    School of Innovation, Design and Engineering, Mälardalen University, Västerås, Sweden.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Evaluating the Sense of Safety and Security in Human - Robot Interaction with Older People2019Inngår i: Social Robots: Technological, Societal and Ethical Aspects of Human-Robot Interaction / [ed] Oliver Korn, Springer, 2019, s. 237-264Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    For many applications where interaction between robots and older people takes place, safety and security are key dimensions to consider. ‘Safety’ refers to a perceived threat of physical harm, whereas ‘security’ is a broad term which refers to many aspects related to health, well-being, and aging. This chapter presents a quantitative evaluation tool of the sense of safety and security for robots in elder care. By investigating the literature on measurement of safety and security in human–robot interaction, we propose new evaluation tools specially tailored to assess interaction between robots and older people.

  • 34.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    School of Innovation, Design and Engineering, Mälardalen University, Västerås, Sweden.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    The Influence of Feedback Type in Robot-Assisted Training2019Inngår i: Multimodal Technologies and Interaction, E-ISSN 2414-4088, Vol. 3, nr 4Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Robot-assisted training, where social robots can be used as motivational coaches, provides an interesting application area. This paper examines how feedback given by a robot agent influences the various facets of participant experience in robot-assisted training. Specifically, we investigated the effects of feedback type on robot acceptance, sense of safety and security, attitude towards robots and task performance. In the experiment, 23 older participants performed basic arm exercises with a social robot as a guide and received feedback. Different feedback conditions were administered, such as flattering, positive and negative feedback. Our results suggest that the robot with flattering and positive feedback was appreciated by older people in general, even if the feedback did not necessarily correspond to objective measures such as performance. Participants in these groups felt better about the interaction and the robot.

  • 35.
    Akbari, Aliakbar
    et al.
    Institute of Industrial and Control Engineering (IOC), Universitat Politècnica de Catalunya (UPC)—Barcelona Tech, Barcelona, Spain.
    Lagriffoul, Fabien
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Rosell, Jan
    Institute of Industrial and Control Engineering (IOC), Universitat Politècnica de Catalunya (UPC)—Barcelona Tech, Barcelona, Spain.
    Combined heuristic task and motion planning for bi-manual robots2019Inngår i: Autonomous Robots, ISSN 0929-5593, E-ISSN 1573-7527, Vol. 43, nr 6, s. 1575-1590Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Planning efficiently at task and motion levels allows the setting of new challenges for robotic manipulation problems, like for instance constrained table-top problems for bi-manual robots. In this scope, the appropriate combination of task and motion planning levels plays an important role. Accordingly, a heuristic-based task and motion planning approach is proposed, in which the computation of the heuristic addresses a geometrically relaxed problem, i.e., it only reasons upon objects placements, grasp poses, and inverse kinematics solutions. Motion paths are evaluated lazily, i.e., only after an action has been selected by the heuristic. This reduces the number of calls to the motion planner, while backtracking is reduced because the heuristic captures most of the geometric constraints. The approach has been validated in simulation and on a real robot, with different classes of table-top manipulation problems. Empirical comparison with recent approaches solving similar problems is also reported, showing that the proposed approach results in significant improvement both in terms of planing time and success rate.

  • 36.
    Akeh, Lucas Kunene
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    Investigating the Challenges and Opportunities for the Adoption use of Electronic Medical Record in Cameroon. A qualitative study.2008Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
  • 37.
    Al-Ali, Mohammed
    et al.
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Sokhan, Sereyvisith
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Remote Monitoring Technologies: The Improvement of Health Care Service for COPD Patients2016Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
  • 38.
    Al-Ali, Mohammed
    et al.
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Zahir, Ako
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Agile Software Requirements Handling Expectations of Product Owner: Theories and Practices2015Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 39.
    Albadawi, Salem
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Improvement of Information Infrastructure for the North Hebron Directorate of Education2014Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 40.
    Albadawi, Salem
    et al.
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Azizi, Fereshta
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Success factors in Healthcare Information Technology: A study about how Healthcare and IT vendor companies address the success factors2015Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
  • 41.
    Albitar, Houssam
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    In-water surface cleaning robot: concept, locomotion and stability2014Inngår i: International Journal of Mechatronics and Automation, ISSN 2045-1067, Vol. 4, nr 2, s. 104-115Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper introduces a new concept of flexible crawling mechanism in the design ofindustrial in-water cleaning robot, which is evaluated from the viewpoint of work and operationon an underwater surface. It enables the scanning and cleaning process performed by water jets,while keeping stable robot position on the surface by its capacity to bear and compensate the jetreactions. Such robotic platform can be used for cleaning and maintenance of various underwatersurfaces, including moving ships in the open sea. The designed robot implements its motions bycontraction and expansion of legged mechanism using standard motors and suction cupstechnology. In this study we focus at the conditions for achieving enough adhesion for keepingcontinuous contact between the robot and the surface and robot stability in different situations forthe basic locomotions.

  • 42.
    Albitar, Houssam
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    New concept of in-water surface cleaning robot2013Inngår i: Mechatronics and Automation (ICMA), 2013 IEEE International Conference onDate 4-7 Aug. 2013, IEEE conference proceedings, 2013, s. 1582-1587Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper introduces a new concept of flexible crawling mechanism to design an industrial underwater cleaning robot, which is evaluated from the viewpoint of the capability to work underwater, scanning the desired surface, and bearing the reactions. This can be used as a robotic application in underwater surface cleaning and maintenance. We designed a robot that realizes the motion by contraction and extraction using DC-motors and vacuum technology. In this study we first focused on realizing the adhesion, bearing reactions, and achieving a stable locomotion on the surface.

  • 43.
    Albitar, Houssam
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Stability study of underwater crawling robot on non-horizontal surface2014Inngår i: Mobile Service Robotics: Clawar 2014: 17th International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines: Poznan, Poland 21 - 23 July 2014, Singapore: World Scientific, 2014, s. 511-519Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper introduces a study of a concept of exible crawling mechanism todesign an industrial underwater cleaning robot, which is evaluated from theviewpoint of the capability to work underwater, scanning the desired surface,and bearing the reactions. This can be used as a robotic application in under-water surface cleaning and maintenance. In this study we focused on realizingthe adhesion on the surface in stationary and in motion, bearing reactions,enabling the needed locomotion types for scanning, and achieving the stabilityin dierent situations on the surface.

  • 44.
    Albitar, Houssam
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Dandan, Kinan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Layered mission control architecture and strategy for crawling underwater cleaning robot2015Inngår i: International Journal of Mechatronics and Automation, ISSN 2045-1059, Vol. 5, nr 2/3, s. 114-124Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents the mechanical design and the control system architecture of anunderwater robot, developed for bio-fouling cleaning surfaces. The robotic system presented herehas been designed to improve the productivity, reduce the environmental impacts, and excludethe hazards for the operators. The control system has a layered structure which is distributed intotwo blocks: cleaning robot, and on-board base station connected with power and control cablesand a water hose, to facilitate different modes of operations and to increase the system reliability.A low level control has been implemented on the robotic platform. The onboard station designedto be in different layers of the control system: manual, semiautonomous and autonomous modes.A scaled prototype has been implemented and tested to prove the concept, and to make certainthat the mechanical design and the chosen control system are perfectly suited to the mainfunctions of the robotic system.

  • 45.
    Albitar, Houssam
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Dandan, Kinan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Underwater Robotics: Surface Cleaning Technics, Adhesion and Locomotion Systems2016Inngår i: International Journal of Advanced Robotic Systems, ISSN 1729-8806, E-ISSN 1729-8814, Vol. 13, artikkel-id 7Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Underwater robots are being developed for various applications ranging from inspection to maintenance and cleaning of submerged surfaces and constructions. These platforms should be able to travel on these surfaces. Furthermore, these platforms should adapt and reconfigure for underwater environment conditions and should be autonomous. Regarding the adhesion to the surface, they should produce a proper attaching force using a light-weight technics. Taking these facts into consideration, this paper presents a survey of different technologies used for underwater cleaning and the available underwater robotics solutions for the locomotion and the adhesion to surfaces.

  • 46.
    Albrecht, Stefan
    et al.
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Axelsson, Morgan
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Umbraco, EPiServer, WordPress, Drupal och egen-utvecklade CMS - Utvecklares åsikter2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 47.
    Al-Dabbagh, Mustafa
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    Electronic Government in Iraq: Challenges of development and implementation2011Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 48.
    Aldammad, Mohamad
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Current collector for heavy vehicles on electrified roads2014Inngår i: Proceedings of the 14th Mechatronics Forum International Conference, Mechatronics 2014 / [ed] Leo J De Vin and Jorge Solis, Karlstad: Karlstads universitet , 2014, s. 436-441Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents a prototype of a novel current collector manipulator that can be mounted beneath a road vehicle between the front and rear wheels to collect electric power from road embedded power lines. The ground-level power supply concept for road vehicles is described and the kinematic model of this two degree of freedom manipulator is detailed. Finally, the power line detection, based on an array of inductive sensors, is discussed.

  • 49.
    Aldammad, Mohamad
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kalaykov, Ivan
    Center for Applied Autonomous Sensor Systems, Örebro University, Örebro, Sweden.
    Current Collector for Heavy Vehicles on Electrified Roads: Field Tests2016Inngår i: Journal of Asian Electric Vehicles, ISSN 1348-3927, Vol. 14, nr 1, s. 1751-1757Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present the field tests and measurements performed on a novel current collector manipulator to be mounted beneath a heavy vehicle to collect electric power from road embedded power lines. We describe the concept of the Electric Road System (ERS) test track being used and give an overview of the test vehicle for testing the current collection. The emphasis is on the field tests and measurements to evaluate both the vertical accelerations that the manipulator’s end-effector is subject to during operation and the performance of the detection and tracking of the power line.

  • 50.
    Aldammad, Mohamad
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Current collector for heavy vehicles on electrified roads: kinematic analysisInngår i: International Journal of Electric and Hybrid Vehicles, ISSN 1751-4088Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a prototype of a novel current collector manipulator to be be mounted beneath a heavy vehicle to collect electric power from road-embedded power lines. We describe the concept of the ground-level power supply system for heavy vehicles and its main components. The main requirements and constraints, such as safety, robustness to harsh road and weather operational conditions, ambient environment aspects and dynamic properties, are introduced. The emphasis is on the developed kinematic model, which provides the base for further development of the control system. We propose and derive an alternative approach for representing the inverse kinematics by a two-dimensional polynomial approximation that avoids the usage of complicated non-linear equations. Its simplicity is demonstrated by a numerical example with the basic parameters of the prototype. The basic motion sequences of the current collector and the way to control them are outlined. 

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