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  • 1.
    Abdul Khaliq, Ali
    et al.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Point-to-point safe navigation of a mobile robot using stigmergy and RFID technology2016In: 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Institute of Electrical and Electronics Engineers (IEEE), 2016, p. 1497-1504, article id 7759243Conference paper (Refereed)
    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.

  • 2.
    Abdulkareem, Ahmed
    et al.
    Örebro University, School of Science and Technology.
    Al-Radi, Omar
    Örebro University, School of Science and Technology.
    Evaluating the measured grip stiffness of different carton board material properties and geometries2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This candidate thesis reports the findings of a study on an objective method for measuring grip stiffness in carton board packages with different geometries and material properties. Syntouch Biotac and a tensile tester were used as an objective method for measuring grip stiffness. In this project tests were carried out on packages with three different grammages and two different geometries. For each grammage and geometry, ten packages were tested.

    The study identifies that the applied method for the measurement of grip stiffness works to measure the change in grip stiffness regardless of where a load was applied on a package. Furthermore, the method demonstrates reasonable results. Finally, the study concluded that the objective testing method could distinguish between different material properties and geometries of the cartons being measured.

  • 3.
    Abdullah, Aram
    et al.
    Örebro University, School of Science and Technology.
    Oktay, Samuel
    Örebro University, School of Science and Technology.
    Översyn av arbetstidsförläggning2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In order to keep up with the construction industry development it is important to be competitive. Many building contractors strive short construction times, which some- times can be difficult to achieve. In order to achieve short construction times you have to find clever solutions and a good production technic that ultimately gives a good re- sult. Shorter construction time contributes to lower costs for contractors.

    Something that is rare in today's construction industry is an extended working time this is something untried in Örebro. In the current situation a construction site opens about 07.00 and closes again for the day at 16.00, Monday to Friday. After 16.00 the construc- tion is stopped. This contributes to an inefficient use of the expenses found at a con- struction site. By extending the current working time with a few hours per day, it will hopefully contribute to a more efficiency use of the costs found at a construction site and also that the number of construction days decreases.

    In the current situation construction workers in PEAB se an extended working time negatively. According to PEAB this is because they do not understand their position in a business way within the company. PEAB argue that construction workers "permanent employment" is not a particularly secure employment. They argue that the only way to get a secure job is to PEAB in partnership with their employees can go get new jobs and deliver results together with their workers. The question then is how PEAB will be able to distinguish themselves from all other construction companies and gain a competitive advantage. According to Fredrik Ahl, Project Manager at PEAB, the solution is an ex- tended working time.

    This report aims to examine how a change in the current working time will affect the cost of a construction site. We also examined the reactions that occur among workers and officials when working hours are changing. 

  • 4.
    Abdullah, Muhammad
    Örebro University, School of Science and Technology.
    Mobile Robot Navigation using potential fields andmarket based optimization2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A team of mobile robots moving in a shared area raises the problem of safe and autonomous navigation. While avoiding static and dynamic obstacles, mobile robots in a team can lead to complicated and irregular movements. Local reactive approaches are used to deal with situations where robots are moving in dynamic environment; these approaches help in safe navigation of robots but do not give optimal solution. In this work a 2-D navigation strategy is implemented, where a potential field method is used for obstacle avoidance. This potential field method is improved using fuzzy rules, traffic rules and market based optimization (MBO). Fuzzy rules are used to deform repulsive potential fields in the vicinity of obstacles. Traffic rules are used to deal situations where two robots are crossing each other. Market based optimization (MBO) is used to strengthen or weaken repulsive potential fields generated by other robots based on their importance. For the verification of this strategy on more realistic vehicles this navigation strategy is implemented and tested in simulation. Issues while implementing this method and limitations of this navigation strategy are also discussed. Extensive experiments are performed to examine the validity of MBO navigation strategy over traditional potential field (PF) method.

  • 5.
    Abrikossova, Natalia
    et al.
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden .
    Skoglund, Caroline
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden; Division of Clinical Medicine, Department of Biomedicine, Örebro University, Örebro, Sweden.
    Ahrén, Maria
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
    Bengtsson, Torbjörn
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Division of Clinical Medicine, Department of Biomedicine, School of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Uvdal, Kajsa
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
    Effects of gadolinium oxide nanoparticles on the oxidative burst from human neutrophil granulocytes2012In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 23, no 27, article id 275101Article in journal (Refereed)
    Abstract [en]

    We have previously shown that gadolinium oxide (Gd2O3) nanoparticles are promising candidates to be used as contrast agents in magnetic resonance (MR) imaging applications. In this study, these nanoparticles were investigated in a cellular system, as possible probes for visualization and targeting intended for bioimaging applications. We evaluated the impact of the presence of Gd2O3 nanoparticles on the production of reactive oxygen species (ROS) from human neutrophils, by means of luminol-dependent chemiluminescence. Three sets of Gd2O3 nanoparticles were studied, i.e. as synthesized, dialyzed and both PEG-functionalized and dialyzed Gd2O3 nanoparticles. In addition, neutrophil morphology was evaluated by fluorescent staining of the actin cytoskeleton and fluorescence microscopy. We show that surface modification of these nanoparticles with polyethylene glycol (PEG) is essential in order to increase their biocompatibility. We observed that the as synthesized nanoparticles markedly decreased the ROS production from neutrophils challenged with prey (opsonized yeast particles) compared to controls without nanoparticles. After functionalization and dialysis, more moderate inhibitory effects were observed at a corresponding concentration of gadolinium. At lower gadolinium concentration the response was similar to that of the control cells. We suggest that the diethylene glycol (DEG) present in the as synthesized nanoparticle preparation is responsible for the inhibitory effects on the neutrophil oxidative burst. Indeed, in the present study we also show that even a low concentration of DEG, 0.3%, severely inhibits neutrophil function. In summary, the low cellular response upon PEG-functionalized Gd2O3 nanoparticle exposure indicates that these nanoparticles are promising candidates for MR-imaging purposes.

  • 6.
    Abu Baker Karim, Aria
    et al.
    Örebro University, School of Science and Technology.
    Schnelzer, Anna
    Örebro University, School of Science and Technology.
    Optimering av glidlager och utveckling av dess konstruktion2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    We have in this project become engrossed in a plain bearing design that is located in a screw press. The screw press compact an unknown mass that is confidential. Robustus have a suggestion to over dimensioning the present plain bearing. The aim of this project was to analyze and to do an optimization on some plain bearings and compare them to the present bearing and to take the choice of material and the environment where the bearing is located into account. The analysis and the optimizations showed that the current plain bearing had the best geometry but not the optimal material selection. The project is in an early state and it needs some geometrical changes. The most important of everything is that the problem has been identified with the help of the wrecked plain bearing and with an excel model.

  • 7.
    Adayson, Christian
    et al.
    Örebro University, School of Science and Technology.
    Ashor, Denkha
    Örebro University, School of Science and Technology.
    Analysering av förbättringsförslag till byggproduktion - En studie baserad på Lean2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, production in the construction industry has evolved into a costlier construction. It has become poorer productivity and increased construction defect attributed to scientific development. They can include notes that 40% of employees time at work goes to value-added work. Construction industry is inefficient in comparison to other manufacturing industries which has 65-75% in value-added work. It is also clear that the costs in the construction sector can be reduced by 30-35%. The authorities in the various reports conveyed its current troubles and that the renovation industry needs.

    The study was done with the help of interviews and a questionnaire analysis on several construction sites to investigate if the problem persists. We chose to focus on four different construction companies working on similar sized projects. By this is obtained a greater overview of the practical work steps.

    The aim is to offer suggestions for improvement using Lean to building production.

    The work delineated on studying waste, orderliness, and continuous improvement.

    The work began with a thorough literature search and through scientific articles. This was done in order to get an overall picture of Lean and also to analyze the problem in the construction industry.

    Lean is about making work more efficiently by managing resources properly. It aims to eliminate unnecessary waste and making continuous improvements. It is an approach that has been used in manufacturing and have been designed by Toyota Automotive Group. Given its present situation in the construction industry want to study, explore opportunities Lean can bring in terms of efficiency and reduction of costs of production.

    It can be ascertained is that workplaces are still gaps in the understanding of what waste is. They are not sufficiently informed and prioritize sometimes the wrong kind of waste. During the interviews it became apparent major gaps in knowledge on the issue. Wrong priorities result that it becomes a messy workplace, which in turn makes it less environmentally friendly and can thus cause injuries.

    Through that process and maintain order in the workplace, it provides the opportunity for a larger workspace that is more flexible, higher quality of performance, employee ergonomics are better and there is less risk of injury.

  • 8.
    Agélii Genlott, Annika
    et al.
    Örebro University, Örebro University School of Business.
    Grönlund, Åke
    Örebro University, Örebro University School of Business.
    Att lära sig läsa och skriva - i nutid och för framtid2014In: Interaktiva medier och lärandemiljöer / [ed] Elza Dunkels; Simon Lindgren, Malmö: Gleerups Utbildning AB, 2014, 1, p. 155-166Chapter in book (Refereed)
  • 9.
    Ahari, Elias
    et al.
    Örebro University, School of Science and Technology.
    Eliasson, Erik
    Örebro University, School of Science and Technology.
    UNDERSÖKNING AV OMSTÄLLNINGSTIDER OCH VARIATIONER VID KARTONGMASKIN 2: EN FALLSTUDIE PÅ IGGESUND PAPERBOARD AB, IGGESUND2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Iggesund Mill manufactures bleached board that is used in exclusive packaging. Iggesund Mill is a part of the Holmen Groupand is located almost 30 scandinavian miles north of Stockholm. A strategic initiative has been launched at Iggesund Mill, which includes improving the working environment, increasing participation and increasing the ability to produce high quality board.

    In this study, changeovers and the variations that occur on the board machine 2 (KM2)have been investigated. This work has been conducted as a qualitative case study where interviews and observations have been analyzed with theoretical support. Early in the study it proved difficult to determine the changeover times at KM2. This may be due to an uncertainty regarding how to report changeovers, which creates a misleading picture of the changeover problems. The conclusion of this is that Iggesund Mill should clearly define the term "Changeover". The variety of products also leads to a lot of changeovers which leads to variations in the process that adversely affect the productivity. A recommendation for a continued work is to investigate whether the product variety can be reduced or the possibility to run larger production cycles.

  • 10.
    Ahmed, Mobyen Uddin
    et al.
    Örebro University, School of Science and Technology.
    Banaee, Hadi
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Health monitoring for elderly: an application using case-based reasoning and cluster analysis2013In: ISRN Artificial Intelligence, ISSN 2090-7435, E-ISSN 2090-7443, Vol. 2013, no 2013, p. 1-11Article in journal (Refereed)
    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.

  • 11.
    Ahmed, Mobyen Uddin
    et al.
    Örebro University, School of Science and Technology.
    Islam, Asif Moinul
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    A case-based patient identification system using pulseoximeter and a personalized health profile2012Conference paper (Refereed)
    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.

  • 12.
    Ahmed, Muhammad Rehan
    Örebro University, School of Science and Technology.
    Compliance Control of Robot Manipulator for Safe Physical Human Robot Interaction2011Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Inspiration from biological systems suggests that robots should demonstrate same level of capabilities that are embedded in biological systems in performing safe and successful interaction with the humans. The major challenge in physical human robot interaction tasks in anthropic environment is the safe sharing of robot work space such that robot will not cause harm or injury to the human under any operating condition.

    Embedding human like adaptable compliance characteristics into robot manipulators can provide safe physical human robot interaction in constrained motion tasks. In robotics, this property can be achieved by using active, passive and semi active compliant actuation devices. Traditional methods of active and passive compliance lead to complex control systems and complex mechanical design.

    In this thesis we present compliant robot manipulator system with semi active compliant device having magneto rheological fluid based actuation mechanism. Human like adaptable compliance is achieved by controlling the properties of the magneto rheological fluid inside joint actuator. This method offers high operational accuracy, intrinsic safety and high absorption to impacts. Safety is assured by mechanism design rather than by conventional approach based on advance control. Control schemes for implementing adaptable compliance are implemented in parallel with the robot motion control that brings much simple interaction control strategy compared to other methods.

    Here we address two main issues: human robot collision safety and robot motion performance.We present existing human robot collision safety standards and evaluate the proposed actuation mechanism on the basis of static and dynamic collision tests. Static collision safety analysis is based on Yamada’s safety criterion and the adaptable compliance control scheme keeps the robot in the safe region of operation. For the dynamic collision safety analysis, Yamada’s impact force criterion and head injury criterion are employed. Experimental results validate the effectiveness of our solution. In addition, the results with head injury criterion showed the need to investigate human bio-mechanics in more details in order to acquire adequate knowledge for estimating the injury severity index for robots interacting with humans.

    We analyzed the robot motion performance in several physical human robot interaction tasks. Three interaction scenarios are studied to simulate human robot physical contact in direct and inadvertent contact situations. Respective control disciplines for the joint actuators are designed and implemented with much simplified adaptable compliance control scheme.

    The series of experimental tests in direct and inadvertent contact situations validate our solution of implementing human like adaptable compliance during robot motion and prove the safe interaction with humans in anthropic domains.

  • 13.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Semi-active compliant robot enabling collision safety for human robot interaction2010In: 2010 International Conference on Mechatronics and Automation (ICMA), IEEE, 2010, p. 1932-1937Conference paper (Refereed)
    Abstract [en]

    Human robot interaction (HRI) tasks requires robots to have safe sharing of work space and to demonstrate adaptable compliant behavior enabling eminent collision safety as well as maintaining high position accuracy. Robot compliance control 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 proposed a unique method using semi-active compliant actuation mechanism having magneto-rheological (MR) fluid based actuator that introduces reconfigurable compliance characteristics into the robot joints. This enables high intrinsic safety coming from fluid mechanics as well as, it offers simpler interaction control strategy compared to other concurrent approaches. In this studies, we have described three essential modes of motions required for physical human system interaction. Furthermore, we have demonstrated robot collision safety in terms of static collision and experimentally validates the performance of robot manipulator enabling safe human robot interaction.

  • 14.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Static and dynamic collisionsafety for human robot interaction using magneto-rheological fluid based compliant robot manipulator2010In: IEEE international conference on robotics and biomimetics (ROBIO), 2010, IEEE conference proceedings, 2010, p. 370-375Conference paper (Refereed)
    Abstract [en]

    The success of human robot interaction (HRI) tasks is characterized by evaluating robot performance in terms of collision safety and position accuracy. Hence, both position accuracy and collision safety are equally indispensable. HRI refers to cognitive as well as physical interaction. Cognitive human robot interaction based on perception and awareness where as physical human robot interaction demands direct contact with the humans exhibiting adaptable compliant behavior. Therefore, development of ideal safe robot manipulator having adaptable compliant actuation is inevitable. Adaptable compliance can be achieved by using active compliant actuation requiring various sensor data or by using passive compliant devices with high mechanical complexity. We present magneto rheological fluid based compliant actuation mechanism introducing adaptable compliance directly into robotic joint with much simpler interaction control and higher intrinsic safety originating from fluid mechanics. In this study, we have discussed adaptable compliance in terms of essential modes of motion for safe physical HRI and evaluated the safety performance of our robot for static collision testing and dynamic collision testing based on impact force and head injury criterion. Finally, the experimental results validate the significance of our proposed method for both human robot collision safety and high position accuracy.

  • 15.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Static collision analysis of semi active compliant robot for safe human robot interaction2010In: Proceedings of the 12th Mechatronics Forum Biennial International Conference, IWF Institute of Machine tools and manufacturing , 2010, p. 220-227Conference paper (Refereed)
  • 16.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Two link compliant robot manipulator for physical human robot collision safety2012In: Biomedical Engineering Systems and Technologies / [ed] Ana Fred, Joaquim Filipe, Hugo Gamboa, Springer, 2012Conference paper (Refereed)
  • 17.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani V.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Compliant motion control for safe human robot interaction2009In: Robot motion and control 2009 / [ed] Krzysztof R. Kozłowski, Berlin: Springer , 2009, p. 265-274Conference paper (Refereed)
    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.

  • 18.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani V.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan G.
    Örebro University, School of Science and Technology.
    Safe robot with reconfigurable compliance/stiffness actuation2009In: Proceedings of ASME/IFToMM International Conference on Reconfigurable Mechanisms and Robots. ReMAR'2009 / [ed] J. S. Dai, M. Zoppi, X. W. Kong, IEEE, 2009, p. 633-638Conference paper (Refereed)
    Abstract [en]

    Human robot interaction (HRI) in constrained motion tasks requires robots to have safe sharing of work space and to demonstrate adaptable compliant behavior Compliance control 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 a unique method using a novel actuation mechanism based on magneto-rheological fluid (MRF) that incorporates reconfigurable compliance directly into the robot joints. This brings much simple interaction control strategy compared to other antagonistic methods. In this studies, we have described three essential modes of motions required for physical human system interaction. Then we have discussed their respective control disciplines. Finally, we have presented functional performance of reconfigurable MRF actuation mechanism in constrained motion tasks by simulating various HRI scenarios.

  • 19.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Modeling of magneto rheological fluid actuator enabling safe human-robot interaction2008In: IEEE International Conference on Emerging Technologies and Factory Automation, 2008. ETFA 2008, 2008, p. 974-979Conference paper (Refereed)
    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.

  • 20.
    Akalin, Neziha
    et al.
    Örebro University, School of Science and Technology.
    Kiselev, Andrey
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    An Evaluation Tool of the Effect of Robots in Eldercare on the Sense of Safety and Security2017In: 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, p. 628-637Conference paper (Refereed)
    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.

  • 21.
    Akalin, Neziha
    et al.
    Örebro University, School of Science and Technology.
    Kiselev, Andrey
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Enhancing Social Human-Robot Interaction with Deep Reinforcement Learning.2018In: Proc. FAIM/ISCA Workshop on Artificial Intelligence for Multimodal Human Robot Interaction, 2018, MHRI , 2018, p. 48-50Conference paper (Refereed)
    Abstract [en]

    This research aims to develop an autonomous social robot for elderly individuals. The robot will learn from the interaction and change its behaviors in order to enhance the interaction and improve the user experience. For this purpose, we aim to use Deep Reinforcement Learning. The robot will observe the user’s verbal and nonverbal social cues by using its camera and microphone, the reward will be positive valence and engagement of the user.

  • 22.
    Akbari, Haris
    et al.
    Örebro University, School of Science and Technology.
    Amel, Hadzic
    Svensk vindkraft2012Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
  • 23.
    Albaldawi, Hisham
    et al.
    Örebro University, School of Science and Technology.
    Kobbah, Diana
    Örebro University, School of Science and Technology.
    Dimensionering av Traverskranbana2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Crane Loads acts on runways which varies with time and cannot be treated as static loads, this allows that the static estimation is not secure enough, therefore the crane runways should be designed in such terms that it can handle static as well as dynamic crane loads.

    The work was chosen after feasibility studies which were made on the internet to get basic knowledge on the subject. The information was sought in Swedish, English and German in order to find relevant and reliable sources which deal with overhead crane runway according to Eurocode. Thanks to advice from Björn Åsted from the Steel Construction Institute (SBI), a book in German was found. In order to compare the results, a Swedish software CraneGirder EC3 was used during the project. The report contains a calculation method for a rolled section girder, calculations were based on Eurocode equations and regulations which were the design basis for the project. The report refer to how a crane runway must be designed with a high utilization level, a number of controls were made to ensure that the beam and its details, such as rail and welding are surely designed to fatigue and deformation. The design was based on load calculations for the overhead crane. Traditional calculations showed how different crane loads can be combined in load groups to achieve the highest impact on the beam, calculations showed that HEB 280 and dimensioning dominated only by load group 1 and 5. With the help of calculation software the results were largely consistent with the program but with some differences. For the delimitation that was assumed in the project the fatigue seemed to have an effect especially on some small details like weld.

  • 24.
    Albitar, Houssam
    Örebro University, School of Science and Technology.
    Enabling a Robot for Underwater Surface Cleaning2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biofouling build-up on submerged structures such as ships, petroleum and gas storage tanks, electric power plants, bridges, oil rigs etc. is a major problem that affects the surface material of the structure, the eventual hydrodynamic quality of the surface and in some cases the efficacy of cooling systems. Underwater cleaning is a solution to maintain submerged structures in order to assure proper functioning for as long as possible. Consequently, there has been an increased interest in the development of new technologies for robotised underwater cleaning systems.

    This thesis presents a new concept of a flexible crawling mechanism for an industrial underwater cleaning robot, which is evaluated from the viewpoint of its capability to work underwater, scanning the desired surface, and perform a cleaning task. The main research questions investigated in this thesis are: (1.) how to select the most important features in choosing the platform mechanism to fulfil the surface scanning operation, (2.) how to design the platform in order to bear the forces related to the cleaning task, (3.) how to maintain surface contact throughout cleaning, (4.) determine the significant parameters to be monitored in order to ensure stable positioning on the surface during the cleaning process and (5.) how to develop the control of actuators to realise the locomotion and to follow the desired trajectory.

    This thesis begins with a classification and discussion of the available solutions for underwater operation, taking into consideration the benefits and drawbacks, overall efficiency and environmental and human safety issues. From this survey, an underwater mobile robotic platform is designed to address the main requirements and industrial needs. Further, a study and simulation of its mobility and stability on the surface is performed and a complete scenario of the entire cleaning operation is presented. In addition, an overview of the required sensors and the control system is given. Finally, a new robotised system was developed to clean underwater surfaces with minimum active degrees of freedom. A successful simulation and real experimental results were obtained with a simplified lab-scale prototype. The thesis concludes with a summary of future works and outlook for the growing field of underwater cleaning robots.

    List of papers
    1. Underwater Robotics: Surface Cleaning Technics, Adhesion and Locomotion Systems
    Open this publication in new window or tab >>Underwater Robotics: Surface Cleaning Technics, Adhesion and Locomotion Systems
    2016 (English)In: International Journal of Advanced Robotic Systems, ISSN 1729-8806, E-ISSN 1729-8814, Vol. 13, article id 7Article in journal (Refereed) Published
    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.

    Place, publisher, year, edition, pages
    INTECH, 2016
    Keywords
    Underwater Robot, Underwater Cleaning, Bio-fouling, Adhesion, Locomotion
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-47813 (URN)10.5772/62060 (DOI)000368630700001 ()2-s2.0-85002271299 (Scopus ID)
    Available from: 2016-01-28 Created: 2016-01-28 Last updated: 2018-01-10Bibliographically approved
    2. New concept of in-water surface cleaning robot
    Open this publication in new window or tab >>New concept of in-water surface cleaning robot
    2013 (English)In: Mechatronics and Automation (ICMA), 2013 IEEE International Conference onDate 4-7 Aug. 2013, IEEE conference proceedings, 2013, p. 1582-1587Conference paper, Published paper (Refereed)
    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.

    Place, publisher, year, edition, pages
    IEEE conference proceedings, 2013
    Keywords
    climbing robot; inspection
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-30340 (URN)10.1109/ICMA.2013.6618150 (DOI)000335375900267 ()2-s2.0-84887901379 (Scopus ID)978-1-4673-5557-5 (ISBN)
    Conference
    2013 IEEE International Conference on Mechatronics and Automation (ICMA), 4-7 aug. 2013, Takamatsu, Japan
    Available from: 2013-08-27 Created: 2013-08-27 Last updated: 2018-01-11Bibliographically approved
    3. In-water surface cleaning robot: concept, locomotion and stability
    Open this publication in new window or tab >>In-water surface cleaning robot: concept, locomotion and stability
    2014 (English)In: International Journal of Mechatronics and Automation, ISSN 2045-1067, Vol. 4, no 2, p. 104-115Article in journal (Refereed) Published
    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.

    Keywords
    underwater robot, crawling robot, underwater surface cleaning
    National Category
    Computer Sciences
    Identifiers
    urn:nbn:se:oru:diva-35987 (URN)10.1504/IJMA.2014.062338 (DOI)000335375900267 ()2-s2.0-84904859302 (Scopus ID)
    Available from: 2014-08-19 Created: 2014-08-19 Last updated: 2018-01-11Bibliographically approved
    4. Stability study of underwater crawling robot on non-horizontal surface
    Open this publication in new window or tab >>Stability study of underwater crawling robot on non-horizontal surface
    2014 (English)In: 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, p. 511-519Conference paper, Published paper (Refereed)
    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.

    Place, publisher, year, edition, pages
    Singapore: World Scientific, 2014
    Keywords
    Crawling robot, underwater, locomotion, stability
    National Category
    Computer Sciences
    Identifiers
    urn:nbn:se:oru:diva-35985 (URN)000342693100061 ()2-s2.0-85007347787 (Scopus ID)978-981-4623-34-6 (ISBN)
    Conference
    Clawar 2014: 17th International Conference on Climbing and Walking Robots CLAWAR, Poznan, Poland, 21 - 23 July, 2014
    Available from: 2014-08-19 Created: 2014-08-19 Last updated: 2018-01-11Bibliographically approved
    5. Layered mission control architecture and strategy for crawling underwater cleaning robot
    Open this publication in new window or tab >>Layered mission control architecture and strategy for crawling underwater cleaning robot
    2015 (English)In: International Journal of Mechatronics and Automation, ISSN 2045-1059, Vol. 5, no 2/3, p. 114-124Article in journal (Refereed) Published
    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.

    Place, publisher, year, edition, pages
    InderScience Publishers, 2015
    Keywords
    underwater robots, layered control system, crawling robots, bio-fouling cleaning
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-49753 (URN)10.1504/IJMA.2015.075957 (DOI)2-s2.0-84973596360 (Scopus ID)
    Available from: 2016-04-11 Created: 2016-04-11 Last updated: 2018-01-10Bibliographically approved
  • 25.
    Alderholm, Daniel
    et al.
    Örebro University, School of Science and Technology.
    Torstensson, Mattias
    Örebro University, School of Science and Technology.
    Funktionsbaserad undersökning av BENTLEYS POWERCIVIL FOR SWEDEN och Novapoint 19 DCM2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis was accomplished in cooperation with WSP Civils in Örebro in the

    spring of 2014. WSP Civil is in the consulting business of construction orientated

    in roads and terrain. Tools of engineering are crucial to be able to produce a

    good result. Therefore between the years of 2012 and 2013, WSP did an investigation

    regarding to which program would suit their demands. The projects task

    was to compare the existing tool Novapoint with a potential future program

    Bentleys PowerCivil for Sweden.

    The process was accomplished by creating a fictional road in both programs. Different

    functions were compared in a matrix table to be able to get a result in an

    illustrative way.

    The result in this rapport is in favor of PowerCivil for Sweden. It is mainly because

    of their templates but also because of their possibility to apply standards

    to the programs functions.

  • 26.
    Alfredsson, Axel
    et al.
    Örebro University, School of Science and Technology.
    Knutson, Gustav
    Örebro University, School of Science and Technology.
    Analys av driftstopp i ett hyvleri2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Moelven is an industrial group that produces building materials and systems for the construction industry; with its 52 productions units in Norway, Sweden and Denmark, it is one of the biggest in Scandinavia. This study has been carried out in the planing mill at Moelven Valåsen Wood AB in Karlskoga.

    Because of the low utilization rate in the planing mill (65%), it constitutes a bottleneck, meaning it limits the capacity and flow of material, for most of the products. The purpose of the study was to analyze the stoppage in the planing mill in order to make recommendations on how the utilization rate can be increased.

    The study began with a wide perspective to identify the reasons behind this problem. A summary of all stops in the planing mill concluded that set ups of the planer made up for 30% of total stoppage. Because of this, the study was narrowed down to mainly analyze the different types of set ups, which was done through extensive observations and videotaping. The solutions and recommendations that were given are therefore almost entirely regarding set up-time reduction, and more specifically, milling set ups. The recommendations, based on the results of the study, includes:

    • Suggestions on how to separate internal and external set up.

    • Better order of tools through designing a check table.

    Standardizing the procedure by creating a routine and dividing the operators into different work roles.

    Involving everyone in the organization in order to work with continuous improvement.

    A simulation of milling set ups was done by implementing parts of the recommendations – this resulted in a setup up-time reduction of 13 minutes, which corresponds to 32.5%. Because of common denominators, such as movements, the recommendations given are likely generalizable for all set ups.

  • 27.
    Algesten, Johannes
    et al.
    Örebro University, School of Science and Technology.
    Svedberg, Sofie
    Örebro University, School of Science and Technology.
    KONSTRUKTION AV AUTOMATISK PÅHASPLINGSPROCESS VID TILLVERKNING AV BANDSTÅL2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The mission that we have received is to design a device that will automate the coiling processin the manufacture of steel strip. The goal of this project is to develop a production documentation that will form the basis for further development of the product. The production documentation shall include drawings, list of components and a cost estimate. A pilot study was conducted where we visited one of the largest strip steel manufacturer to investigate the solutions they had to our problem. Based on what we saw, a concept generation was made that led to the concept that we proceeded with. In the process, we have placed great emphasis on making the design as simple as possible to get a reasonable production cost. We have also taken into account that the design will be integrated with existing equipment. Regarding cost, we have as far as possible tried to use standard components and standard dimensions of the material in the construction. Parts of the structure exposed to high forces have been analyzed by using ANSYS. The result is a construction with two arms using a belt to envelope the coil. The arm is controlled using a hydraulic cylinder, while the other is positioned when the belt is stretched. The construction will be placed above the coil and lowered when it is used.

  • 28.
    AL-Hindi, Rafah
    et al.
    Örebro University, School of Science and Technology.
    Yousef, Yousef
    Örebro University, School of Science and Technology.
    BIM Byggnadsinformationsmodellering BIM-användning hos de olika aktörerna2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Clarus Arkitekter as design companies often receive orders from contractors and clients asking for a BIM model. In most cases, the BIM model is not fully used, but 3D drawings or 2D drawings are available. Then asks the question "Does the client / contractor have the correct understanding of what BIM is?" Different players have different guidelines and requirements that the projector should follow, which can be perceived as defective by the projector just to know what is demanded from each client. The question the thesis will answer is "How should the consultant do the best to offer the right service and what goals the consultant will do.

    The purpose of this master thesis is to find out how BIM usage could facilitate the work as well as the communication between the various actors who is involved in a construction project. To investigate how the level of competence lies with the Client, Entrepreneur and Projectors / Architects and answerthe question "what is behind the skill difference that exists?".

    The work began with literature studies for the collection and compilation of information. Questions will be set up to later use them during interviews with different people from different companies. The interviews will take place with individuals from consultancy, contractor and client company.

    The interest in using BIM is high in the industry, but unfortunately there is a great deal of skills shortage. Customers and entrepreneurs plan to start using BIM more, which will happen in the coming years, but now, they do not want to take new risks and prefer to use traditional methods that are more secure. To be able to apply BIM more in the construction industry, more knowledge is needed.

  • 29.
    Al-Hussein, Heba
    Örebro University, School of Science and Technology.
    PLATSBASERAD HANTERING AV SÄKERHETSRISKER PÅ EN BYGGARBETSPLATS PÅ SKANSKA2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Should there be a risk working at construction sites?

    This is an issue that is daily discussed by many construction companies. The Construction industry is a major industry that reflects and provides the society with what it needs in order to function, such as residences, hospitals, commercial buildings, roads, bridges, ports etcetera. In order to provide the society all these different types of constructions, there is a risk for those who work at the construction site. Accidents and occupational diseases are about twice as common among construction workers compared to the average worker according to Swedish Work Environment Authority [1].

    Skanska is one of the leading construction companies in Sweden, and is working hard with occupational health and safety issues. There is a vision of zero construction site accidents. "Mitt Gröna Kvarter" is an infill and rebuild project that has focused extra on safety. This extra focus on safety was the reason why this particular project was chosen to study health and safety, and to see how this can be improved more. How the safety should be handled and solved varies depending on the activity to be done and the risk that occurs at that specific location. Skanska has with SBUF support published two reports on how a building drawing can be used to increase the safety on construction sites, by collecting information using a reference group working in different projects.

    This academic work shows a new way to categorize safety risks on construction sites. The report shows how safety risks can be documented on the building drawings and regulations. The categorization method and the risk documentation in drawing and regulations can lower the safety risks in the constructions sites.

    A construction time plan contains all the activities that must be done before a building is completed, and all the safety risks can be linked to the timetable even if this is an ineffective method. In this academic work, studying the project "Mitt Gröna Kvarter", approximately 50% of all the security risks can be linked to a specific location. Therefore both an activity and location specific account of risks is an optimal solution.

  • 30.
    Ali Ibrahim, Yusuf
    Örebro University, School of Science and Technology.
    KOMMUNIKATION OCH INFORMATIONSFLÖDE En studie av förbättringsmöjligheter vid Strängbetongs fabrik i Kungsör: COMMUNICATION AND FLOW OF INFORMATION A study of the improvement opportunities at Strängbetong plant in Kungsör2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Effective communication and unobstructed flow of information is essential for an organization's productivity and efficiency. Previous research on communication and information flow shows that the efficiency and productivity of an organization is correlated with how well the communication and information flow works in the organization. The aim of the work presented in this report is to map and analyze the communication and information flow in Strängbetongs plant in Kungsör. Among the methods used during this work are interviews with staff from different departments and open talks with the production staff in the factory. In addition to interviews and conversations with the staff, how gathered information is used for production monitoring and productivity improvement has also been analyzed.

    How communication and information flow can be improved are presented in the conclusion. The result shows how inadequate communication between different partners whose work hangs together give rise to reduced productivity, increased waiting times and leads to rework and discard.

  • 31.
    Alirezaie, Marjan
    et al.
    Örebro University, School of Science and Technology.
    Kiselev, Andrey
    Örebro University, School of Science and Technology.
    Klügl, Franziska
    Örebro University, School of Science and Technology. Örebro University, School of Law, Psychology and Social Work.
    Längkvist, Martin
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Exploiting Context and Semantics for UAV Path-finding in an Urban Setting2017In: Proceedings of the 1st International Workshop on Application of Semantic Web technologies in Robotics (AnSWeR 2017), Portoroz, Slovenia, May 29th, 2017 / [ed] Emanuele Bastianelli, Mathieu d'Aquin, Daniele Nardi, Technical University Aachen , 2017, p. 11-20Conference paper (Refereed)
    Abstract [en]

    In this paper we propose an ontology pattern that represents paths in a geo-representation model to be used in an aerial path planning processes. This pattern provides semantics related to constraints (i.e., ight forbidden zones) in a path planning problem in order to generate collision free paths. Our proposed approach has been applied on an ontology containing geo-regions extracted from satellite imagery data from a large urban city as an illustrative example.

  • 32.
    Alirezaie, Marjan
    et al.
    Örebro University, School of Science and Technology.
    Kiselev, Andrey
    Örebro University, School of Science and Technology.
    Längkvist, Martin
    Örebro University, School of Science and Technology.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    An Ontology-Based Reasoning Framework for Querying Satellite Images for Disaster Monitoring2017In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 17, no 11, article id 2545Article in journal (Refereed)
    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.

  • 33.
    Alirezaie, Marjan
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Automated reasoning using abduction for interpretation of medical signals2014In: Journal of Biomedical Semantics, ISSN 2041-1480, E-ISSN 2041-1480, Vol. 5, article id 35Article in journal (Refereed)
    Abstract [en]

    This paper proposes an approach to leverage upon existing ontologies in order to automate the annotation of time series medical data. The annotation is achieved by an abductive reasoner using parsimonious covering theorem in order to determine the best explanation or annotation for specific user defined events in the data. The novelty of this approach resides in part by the system’s flexibility in how events are defined by users and later detected by the system. This is achieved via the use of different ontologies which find relations between medical, lexical and numerical concepts. A second contribution resides in the application of an abductive reasoner which uses the online and existing ontologies to provide annotations. The proposed method is evaluated on datasets collected from ICU patients and the generated annotations are compared against those given by medical experts.

  • 34.
    Alirezaie, Marjan
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Ontology alignment for classification of low level sensor data2012Conference paper (Refereed)
  • 35.
    Alirezaie, Marjan
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Reasoning for Improved Sensor Data Interpretation in a Smart Home2014Conference paper (Refereed)
    Abstract [en]

    In this paper an ontological representation and reasoning paradigm has been proposed for interpretation of time-series signals. The signals come from sensors observing a smart environment. The signal chosen for the annotation process is a set of unintuitive and complexgas sensor data. The ontology of this paradigm is inspired form the SSNontology (Semantic Sensor Network) and used for representation of both the sensor data and the contextual information. The interpretation process is mainly done by an incremental ASP solver which as input receivesa logic program that is generated from the contents of the ontology. The contextual information together with high level domain knowledge given in the ontology are used to infer explanations (answer sets) for changes in the ambient air detected by the gas sensors.

  • 36.
    Alirezaie, Marjan
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Towards Automatic Ontology Alignment for Enriching Sensor Data Analysis2013In: Communications in Computer and Information Science, ISSN 1865-0929, E-ISSN 1865-0937, Vol. 415, p. 179-193Article in journal (Refereed)
    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.

  • 37.
    Alirezaie, Marjan
    et al.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Context Recognition: Towards Automatic Query Generation2015In: Ambient Intelligence: 12th European Conference, AmI 2015, Athens, Greece, November 11-13, 2015, Proceedings, Springer, 2015, p. 205-218Conference paper (Refereed)
    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.

  • 38.
    Alirezaie, Marjan
    et al.
    Örebro University, School of Science and Technology.
    Renoux, Jennifer
    Örebro University, School of Science and Technology.
    Köckemann, Uwe
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Blomqvist, Eva
    RISE SICS East, Linköping, Sweden.
    Tsiftes, Nicolas
    RISE SICS, Stockholm, Sweden.
    Voigt, Thiemo
    RISE SICS, Stockholm, Sweden.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    An Ontology-based Context-aware System for Smart Homes: E-care@home2017In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 17, no 7, article id 1586Article in journal (Refereed)
    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.

  • 39.
    Almerstedt, Matilda
    et al.
    Örebro University, School of Science and Technology.
    Lindhé, Johanna
    Örebro University, School of Science and Technology.
    Empirisk studie i form och geometrins upplevda inverkan på konsument produkter2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    It is unclear which mechanical properties that affect consumer products, it can be assumed that the shape and geometry affect the perceived feeling of consumer products. The aim of the project is to examine how the geometry and folding views affect the feeling in the use of consumer products.The study was performed on three consumer products of different dimensions where each product was produced in two different versions. The results showed that consumer product’s geometry is significant, while the folding views do not have a significant impact.

  • 40.
    Almestrand, Lovisa
    Örebro University, School of Science and Technology.
    Passivhus i Örebro län: Undersökning av marknaden för fastighetsägare2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project aims to study the knowledge that property owners have of passive houses and if there is a market for this concept in Örebro County.

    Environmental and climate problems in the world are growing and a result of this is the constant circulating debate of passive houses. Low-energy houses are a necessary solution to reducing energy consumption, then the housing sector accounts for about 40 % of Sweden´s total energy use. Passive houses are a development of the low-energy house built without conventional heating systems and have a low energy use. Asplunds Bygg in Örebro is now building the very first passive houses in Örebro this spring 2009.

    The project began with contacting property owners to book interviews. The interviews were carried out over a four week period at the respective property owner's office. An independent in-depth were made parallel to the interviews by studying passivhus in literature, articles and on the Internet. The results of the interviews were compiled, compared and analyzed based on the purpose of the work.

    Property owners are receptive to the concept and believe that the energy issue is important, but that knowledge into passive houses of some is poor.  Finally found that from the results of the interviews it seems that there is a future market for passive houses in Örebro County. 

    Keywords: passive houses, low-energy houses, energy use, ventilation system, heat recovery, thick insulation.  

  • 41.
    Almér, Ida
    et al.
    Örebro University, School of Science and Technology.
    Hed, Johanna
    Örebro University, School of Science and Technology.
    Utveckling av delningsarm2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes a bachelor degree project conducted at the company EMBA Machinery AB. The company manufactures corrugated cardboard conversion machines. The machines convert cardboard sheets into folded corrugated boxes. EMBA´s machines are so-called internal machines that consist of several devices. The unit involved in the thesis work reported herein was the unit Counter Stacker. The Counter Stacker is the last unit in the EMBA machines, it counts and divides the finished cardboard boxes into bundles.

    EMBA wanted the authors to redesign the function that divides the sheets, the divider arm, in the affected unit. The divider arm should be controlled via electric servo operation and also act as a rebuild kit for previously sold machines.

    Calculations to investigate the stresses that arise at critical points in the design have been carried out. Motion profiles have been developed and motors and gearboxes have been dimensioned. Parallel to this a 3D-model was created in CAD. Based on the CAD-model, the company can proceed with creating complete drawing documents.

  • 42.
    Alzghoul, Ahmad
    et al.
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Löfstrand, Magnus
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Increasing availability of industrial systems through data stream mining2011In: Computers & industrial engineering, ISSN 0360-8352, E-ISSN 1879-0550, Vol. 60, no 2, p. 195-205Article in journal (Refereed)
    Abstract [en]

    Improving industrial product reliability, maintainability and thus availability is a challenging task for many industrial companies. In industry, there is a growing need to process data in real time, since the generated data volume exceeds the available storage capacity. This paper consists of a review of data stream mining and data stream management systems aimed at improving product availability. Further, a newly developed and validated grid-based classifier method is presented and compared to one-class support vector machine (OCSVM) and a polygon-based classifier.

    The results showed that, using 10% of the total data set to train the algorithm, all three methods achieved good (>95% correct) overall classification accuracy. In addition, all three methods can be applied on both offline and online data.

    The speed of the resultant function from the OCSVM method was, not surprisingly, higher than the other two methods, but in industrial applications the OCSVMs' comparatively long time needed for training is a possible challenge. The main advantage of the grid-based classification method is that it allows for calculation of the probability (%) that a data point belongs to a specific class, and the method can be easily modified to be incremental.

    The high classification accuracy can be utilized to detect the failures at an early stage, thereby increasing the reliability and thus the availability of the product (since availability is a function of maintainability and reliability). In addition, the consequences of equipment failures in terms of time and cost can be mitigated.

  • 43.
    Alzghoul, Ahmad
    et al.
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Löfstrand, Magnus
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Backe, Björn
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Data stream forecasting for system fault prediction2012In: Computers & industrial engineering, ISSN 0360-8352, E-ISSN 1879-0550, Vol. 62, no 4, p. 972-978Article in journal (Refereed)
    Abstract [en]

    Competition among today’s industrial companies is very high. Therefore, system availability plays an important role and is a critical point for most companies. Detecting failures at an early stage or foreseeing them before they occur is crucial for machinery availability. Data analysis is the most common method for machine health condition monitoring. In this paper we propose a fault-detection system based on data stream prediction, data stream mining, and data stream management system (DSMS). Companies that are able to predict and avoid the occurrence of failures have an advantage over their competitors. The literature has shown that data prediction can also reduce the consumption of communication resources in distributed data stream processing. In this paper different data-stream-based linear regression prediction methods have been tested and compared within a newly developed fault detection system. Based on the fault detection system, three DSM algorithms outputs are compared to each other and to real data. The three applied and evaluated data stream mining algorithms were: Grid-based classifier, polygon-based method, and one-class support vector machines (OCSVM). The results showed that the linear regression method generally achieved good performance in predicting short-term data. (The best achieved performance was with a Mean Absolute Error (MAE) around 0.4, representing prediction accuracy of 87.5%). Not surprisingly, results showed that the classification accuracy was reduced when using the predicted data. However, the fault-detection system was able to attain an acceptable performance of around 89% classification accuracy when using predicted data.

  • 44.
    Alzghoul, Ahmad
    et al.
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Löfstrand, Magnus
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Karlsson, Lennart
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Karlberg, Magnus
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Data stream mining for increased functional product availability awareness2011In: Functional Thinking for Value Creation: Proceedings of the 3rd CIRP International Conference on Industrial Product Service Systems, Technische Universität Braunschweig, Braunschweig, Germany, May 5th - 6th, 2011 / [ed] Hesselbach, J. & Herrmann, C., Springer Berlin/Heidelberg, 2011, p. 237-241Conference paper (Refereed)
    Abstract [en]

    Functional Products (FP) and Product Service Systems (PSS) may be seen as integrated systems comprising hardware and support services. For such offerings, availability is key. Little research has been done on integrating Data Stream Management Systems (DSMS) for monitoring (parts of) a FP to improve system availability. This paper introduces an approach for how data stream mining may be applied to monitor hardware being part of a Functional Product. The result shows that DSMS have the potential to significantly support continuous availability awareness of industrial systems, especially important when the supplier is to supply a function with certain availability.

  • 45.
    Amato, Giuseppe
    et al.
    ISTI-CNR, Pisa, Italy.
    Broxvall, Mathias
    Örebro University, School of Science and Technology.
    Chessa, Stefano
    Università di Pisa, Pisa, Italy.
    Dragone, Mauro
    University College Dublin, Dublin, Ireland.
    Gennaro, Caludio
    ISTI-CNR, Pisa, Italy.
    Lopez, Rafa
    Robotnik Automation, Valencia, Spain.
    Maguire, Liam
    University of Ulster, Coleraine, Ireland.
    McGinnity, Martin T.
    University of Ulster, Coleraine, Ireland.
    Micheli, Alessio
    Università di Pisa, Pisa, Italy.
    Renteria, Arantxa
    Tecnalia, Derio, Spain.
    O’Hare, Gregory M. P.
    University College Dublin, Dublin, Ireland.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Robotic UBIquitous COgnitive Network2012In: Ambient Intelligence: Software and Applications / [ed] Paulo Novais, Kasper Hallenborg, Dante I. Tapia, Juan M. Corchado Rodríguez, Springer-Verlag New York, 2012, p. 191-195Conference paper (Refereed)
    Abstract [en]

    Robotic ecologies are networks of heterogeneous robotic devices pervasively embedded in everyday environments, where they cooperate to perform complex tasks. While their potential makes them increasingly popular, one fundamental problem is how to make them self-adaptive, so as to reduce the amount of preparation, pre-programming and human supervision that they require in real world applications. The EU FP7 project RUBICON develops self-sustaining learning solutions yielding cheaper, adaptive and efficient coordination of robotic ecologies. The approach we pursue builds upon a unique combination of methods from cognitive robotics, agent control systems, wireless sensor networks and machine learning. This paper briefly illustrates how these techniques are being extended, integrated, and applied to AAL applications.

  • 46.
    Amir, Halmat
    et al.
    Örebro University, School of Science and Technology. Örebro universitet.
    Björk, Chritian
    Örebro universitet.
    EGENKONTROLLER OCH FUKT, EN DEL I KVALITETSARBETET2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To ensure a high quality of the final product it’s important that quality work is considered during the production. Quality work affects the company in a positive way by making our customers happy, improving and retaining our good reputation and leads to a good economy. NCC suspects that there’s insufficient quality work during production in the construction in-dustry across the country and based on that they want us to examine how they’re handling this. In this thesis we’ve done the interviews on five of NCC's ongoing projects in Örebro County in order to provide a picture about how the process of quality controls and moisture at the construction sites works. We’ll identify how employees work with their quality controls and moisture during the production, if there are any deficiencies in the work and in such case what’s causing it.

  • 47.
    Amouzgar, Kaveh
    et al.
    Department of Mechanical Engineering, School of Engineering, Jönköping University, Jönköping, Sweden.
    Rashid, Asim
    Department of Mechanical Engineering, School of Engineering, Jönköping University, Jönköping, Sweden.
    Strömberg, Niclas
    Department of Mechanical Engineering, School of Engineering, Jönköping University, Jönköping, Sweden.
    Multi-objective optimization of a disc brake system by using SPEA2 and RBFN2013In: ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference: Volume 3B: 39th Design Automation Conference, New York: ASME Press, 2013Conference paper (Other academic)
    Abstract [en]

    Many engineering design optimization problems involve multiple conflicting objectives, which today often are obtained by computational expensive finite element simulations. Evolutionary multi-objective optimization (EMO) methods based on surrogate modeling is one approach of solving this class of problems. In this paper, multi-objective optimization of a disc brake system to a heavy truck by using EMO and radial basis function networks (RBFN) is presented. Three conflicting objectives are considered. These are: 1) minimizing the maximum temperature of the disc brake, 2) maximizing the brake energy of the system and 3) minimizing the mass of the back plate of the brake pad. An iterative Latin hypercube sampling method is used to construct the design of experiments (DoE) for the design variables. Next, thermo-mechanical finite element analysis of the disc brake, including frictional heating between the pad and the disc, is performed in order to determine the values of the first two objectives for the DoE. Surrogate models for the maximum temperature and the brake energy are created using RBFN with polynomial biases. Different radial basis functions are compared using statistical errors and cross validation errors (PRESS) to evaluate the accuracy of the surrogate models and to select the most accurate radial basis function. The multi-objective optimization problem is then solved by employing EMO using the strength Pareto evolutionary algorithm (SPEA2). Finally, the Pareto fronts generated by the proposed methodology are presented and discussed.

  • 48.
    Amouzgar, Kaveh
    et al.
    Department of Mechanical Engineering, School of Engineering, Jönköping University, Jönköping, Sweden .
    Strömberg, Niclas
    Department of Engineering Science, University West, Trollhättan, Sweden.
    An approach towards generating surrogate models by using RBFN with a priori bias2014In: Proceedings of the ASME International Design Engineering Technical Conferences & Computers and Information in Engineering Conference, 2014, Vol. 2B, New York, USA: ASME Press, 2014, article id V02BT03A024Conference paper (Refereed)
    Abstract [en]

    In this paper, an approach to generate surrogate modelsconstructed by radial basis function networks (RBFN) with a prioribias is presented. RBFN as a weighted combination of radialbasis functions only, might become singular and no interpolationis found. The standard approach to avoid this is to add a polynomialbias, where the bias is defined by imposing orthogonalityconditions between the weights of the radial basis functionsand the polynomial basis functions. Here, in the proposed a prioriapproach, the regression coefficients of the polynomial biasare simply calculated by using the normal equation without anyneed of the extra orthogonality prerequisite. In addition to thesimplicity of this approach, the method has also proven to predictthe actual functions more accurately compared to the RBFNwith a posteriori bias. Several test functions, including Rosenbrock,Branin-Hoo, Goldstein-Price functions and two mathematicalfunctions (one large scale), are used to evaluate the performanceof the proposed method by conducting a comparisonstudy and error analysis between the RBFN with a priori and aposteriori known biases. Furthermore, the aforementioned approachesare applied to an engineering design problem, that ismodeling of the material properties of a three phase sphericalgraphite iron (SGI) . The corresponding surrogate models arepresented and compared

  • 49.
    Amouzgar, Kaveh
    et al.
    Product Development Department, School of Engineering, Jönköping University, Jönköping, Sweden; School of Engineering Science, University of Skövde, Skövde, Sweden.
    Strömberg, Niclas
    Örebro University, School of Science and Technology. Department of Mechanical Engineering.
    Radial Basis Functions as Surrogate Models with A Priori Bias in Comparison with a Posteriori Bias2017In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 55, no 4, p. 1453-1469Article in journal (Refereed)
    Abstract [en]

    In order to obtain a robust performance, the established approach when using radial basis function networks (RBF) as metamodels is to add a posteriori bias which is defined by extra orthogonality constraints. We mean that this is not needed, instead the bias can simply be set a priori by using the normal equation, i.e. the bias becomes the corresponding regression model. In this paper we demonstrate that the performance of our suggested approach with a priori bias is in general as good as, or even for many test examples better than, the performance of RBF with a posteriori bias. Using our approach, it is clear that the global response is modelled with the bias and that the details are captured with radial basis functions. The accuracy of the two approaches are investigated by using multiple test functions with different degrees of dimensionality. Furthermore, several modeling criteria, such as the type of radial basis functions used in the RBFs, dimension of the test functions, sampling techniques and size of samples, are considered to study their affect on the performance of the approaches. The power of RBF with a priori bias for surrogate based design optimization is also demonstrated by solving an established engineering benchmark of a welded beam and another benchmark for different sampling sets generated by successive screening, random, Latin hypercube and Hammersley sampling, respectively. The results obtained by evaluation of the performance metrics, the modeling criteria and the presented optimal solutions, demonstrate promising potentials of our RBF with a priori bias, in addition to the simplicity and straight-forward use of the approach.

  • 50.
    Ananiev, Anani
    et al.
    Örebro University, Department of Technology.
    Michelfelder, Thorsten
    Örebro University, Department of Technology.
    Kalaykov, Ivan
    Örebro University, Department of Technology.
    Driving redundant robots by a dedicated clutch-based actuator2007In: Robot motion and control 2007 / [ed] Krzysztof Kozłowski, Berlin: Springer , 2007, p. 167-176Conference paper (Other academic)
    Abstract [en]

    The redundancy in the body construction of humans and animals makes them very adaptable for a wide variety of natural environments. By switching/activating/deactivating they can accommodate the necessary locomotion for performing almost any task in their lifes. Therefore redundant and hyper-redundant robots are at the focus of research world-wide. The existing hyper-redundant robotic platforms are built in a plenty of mechanical constructions and purposes of use, but have a limited number of useful features that, unfortunately, limit their applicability in some important areas.

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