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  • 1.
    Arén, Björn
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Dimensionering efter hållfasthet av olika slag2009Inngår i: Uppfinnaren & konstruktören, ISSN 0284-9682, nr 5, s. 32-34Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 2.
    de Miranda, Luis
    et al.
    School of Literatures, Languages and Culture, The University of Edinburgh, UK.
    Ramamoorthy, Subramanian
    School of Informatics, The University of Edinburgh, UK.
    Rovatsos, Michael
    School of Informatics, The University of Edinburgh, UK.
    We, Anthrobot: Learning from Human Forms of Interaction and Esprit de Corps to Develop More Diverse Social Robotics2016Inngår i: WHAT SOCIAL ROBOTS CAN AND SHOULD DO, IOS Press, 2016, Vol. 290, s. 48-59Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We contend that our relationship with robots is too often seen within a universalistic and individualistic mind-frame. We propose a specific perspective in social robotics that we call anthrobotics. Anthrobotics starts with the choice to consider the human-machine intertwining as a dynamic union of more or less institutionalised collectives rather than separated discrete realities (individual humans, on one side, and discrete individualised machines on the other). We draw on our research in types of social interaction and esprit de corps to imagine more plural and harmonious forms of shared natural-artificial cognitive systems. We propose to look at four types of organised groups: conformative, autonomist, creative, and universalistic, that may provide guiding principles for the design of more diverse anthrobots.

  • 3.
    Flyktman, Stefan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Johansson, Jan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Tillverkningsmetoders påverkan på en transmissions vikt och tillverkningskostnad2010Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Volvo Powertrain, VPT, i Köping tillverkar idag växellådor för tunga fordon. Till medeltunga fordon köper Volvo växellådor från bland annat underleverantören ZF. Volvo vill undersöka scenariot att ta fram AMT - växellådor för medeltunga fordon. I-shift modellen AT2412, som är dimensionerad för en max belastning på 2400 Nm och anpassad för tunga lastbilar, skulle kunna fungera även i medeltunga fordon men är då överdimensionerad och onödigt tung.

    Med tanke på kommande utvecklingsprojekt behöver Volvo öka sin kunskap hur val av tillverkningsmetoder påverkar vikt och tillverkningskostnader. Det behövs för att öka förståelsen för hur olika prioriteringar ska göras med avseende på vikt och tillverkningskostnader. Examensarbetets syfte var att ge denna förståelse för hur olika tillverkningsprocesser påverkar en transmissions utformning med avseende på mått och vikt utifrån ett givet momentområde. Målet med examensarbetet var att påvisa samband mellan valet av tillverkningsmetoder för enskilda artiklar och hur mycket det kan påverka den kompletta transmissionens vikt samt tillverkningskostnad. Arbetet var avgränsat till att analysera modifierade kugghjul i baslådan.

    Första delen av arbetet bestod av att dimensionera nya kugghjul anpassade för max belastning på 1600 Nm, detta utifrån samma produktionsupplägg som för befintliga kugghjul som återfinns i bland annat AT2412. Den andra delen bestod av att ta fram faktorer för hur olika tillverkningsmetoder påverkar dimensioneringen och för varje enskilt kugghjul beräkna vikt och tillverkningskostnad då åtta kombinationer av tillverkningsmetoder används. Avslutningsvis gjordes en summering för att visa vilka varianter som ger en optimal växellåda utifrån minimal vikt respektive minimal tillverkningskostnad.

    Resultatet visar att valet av tillverkningsmetoder leder till att vikten på kugghjulen kan reduceras mer eller mindre. Generellt visar beräkningarna att kugghjul som slipas, kulpenas och manganfosfateras får lägst vikt och blir dyrast att producera. Lägsta tillverkningskostnad uppnås genom att vissa tillverkningsprocesser som kulpening och manganfosfatering utesluts men detta måste då kompenseras med ökad kuggbredd vilket leder till högre vikt.

    Om VPT väljer att ta fram en ny variant av I-shift där kugghjulen är dimensionerade för 1600Nm så kan växellådan göras 6-11 kg lättare och tillverkningskostnaderna för kugghjulen kan minska med ca 10 procent.

    Fulltekst (pdf)
    FULLTEXT01
  • 4.
    Jarl, Magnus
    et al.
    Örebro universitet, Institutionen för teknik.
    Axelsson, Fredrik
    Wear of dies, measured and calculated by the process control system in a drawing machine2009Inngår i: Wire Journal International, ISSN 0277-4275, Vol. 42, nr 10, s. 80-83Artikkel i tidsskrift (Fagfellevurdert)
  • 5.
    Ranjbar, Parivash
    et al.
    Örebro universitet, Institutionen för hälsovetenskap och medicin.
    Borg, Erik
    Örebro University Hospital, Örebro, Sweden.
    Philipson, Lennart
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Stranneby, Dag
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Sensing the environment: A perceptual and psychosocial analysis of events in surroundings from a handicapped perspective2003Konferansepaper (Annet vitenskapelig)
  • 6.
    Sattari, Amir
    KTH, Stockholm, Sweden.
    Investigations of Flow Patterns in Ventilated Rooms Using Particle Image Velocimetry: Applications in a Scaled Room with Rapidly Varying Inflow and over a Wall-Mounted Radiator2015Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis introduces and describes a new experimental setup for examining the effects of pulsating inflow to a ventilated enclosure. The study aimed to test the hypothesis that a pulsating inflow has potential to improve ventilation quality by reducing the stagnation zones through enhanced mixing. The experimental setup, which was a small-scale, two-dimensional (2D), water-filled room model, was successfully designed and manufactured to be able to capture two-dimensional velocity vectors of the entire field using Particle Image Velocimetry (PIV). Using in-house software, it was possible to conclude that for an increase in pulsation frequency or alternatively in the flow rate, the stagnation zones were reduced in size, the distribution of vortices became more homogeneous over the considered domain, and the number of vortices in all scales had increased. Considering the occupied region, the stagnation zones were moved away in a favorable direction from a mixing point of view. In addition, statistical analysis unveiled that in the far-field occupied region of the room model, stronger eddies were developed that we could expect to give rise to improved mixing. As a fundamental experimental study performed in a 2D, small-scale room model with water as operating fluid, we can logically conclude that the positive effect of enhanced mixing through increasing the flow rate could equally be accomplished through applying a pulsating inflow.

    In addition, this thesis introduces and describes an experimental setup for study of air flow over a wall-mounted radiator in a mockup of a real room, which has been successfully designed and manufactured. In this experimental study, the airflow over an electric radiator without forced convection, a common room-heating technique, was measured and visualized using the 2D PIV technique. Surface blackening due to particle deposition calls for monitoring in detail the local climate over a heating radiator. One mechanism causing particle deposition is turbophoresis, which occurs when the flow is turbulent. Because turbulence plays a role in particle deposition, it is important to identify where the laminar flow over radiator becomes turbulent. The results from several visualization techniques and PIV measurements indicated that for a room with typical radiator heating, the flow over the radiator became agitated after a dimensionless length, 5.0–6.25, based on the radiator thickness.

    Surface properties are among the influencing factors in particle deposition; therefore, the geometrical properties of different finishing techniques were investigated experimentally using a structured light 3D scanner that revealed differences in roughness among different surface finishing techniques. To investigate the resistance to airflow along the surface and the turbulence generated by the surfaces, we recorded the boundary layer flow over the surfaces in a special flow rig, which revealed that the types of surface finishing methods differed very little in their resistance and therefore their influence on the deposition velocity is probably small. 

    Fulltekst (pdf)
    Spikblad
  • 7.
    Sattari, Amir
    Building Technology, Dalarna University, Falun, Sweden; University of Gävle, Gävle, Sweden; Royal Institute of Technology (KTH), Stockholm, Sweden.
    Particle Image Velocimetry Visualization and measurement of Airflow over a Wall-Mounted Radiator2015Inngår i: The International Journal of Ventilation, ISSN 1473-3315, E-ISSN 2044-4044, Vol. 14, nr 3, s. 289-302Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A common room-heating technique involves the use of a wall-mounted radiator without forced convection. The cold surrounding air passes adjacent to the warm surfaces of the radiator where it absorbs heat and gains momentum to rise along the wall surface and finally circulate in the entire room. Understanding the properties of heated airflows is important for several purposes. To understand the flow process it is important to identify where the transition from laminar to turbulent flow occurs and to quantify the turbulent fluctuations. With the objective to characterize the airflow in the vicinity of wall surfaces, the local climate over the radiator was visualized and measured using a two-dimensional particle image velocimetry technique. The PIV technique yields 2D vector fields of the flow. The resulting vector maps were properly validated and post-processed using in-house software to provide the average streamlines and other statistical information such as standard deviation, average velocity, and covariance of the entire vector field. The results show that, for a room with a typical heating power, the airflow over the radiator becomes agitated after an ordinate of N = 5 - 6.25 over the radiator upper level, in which N is the dimensionless length based on the thickness of the radiator. Practical problems encountered in near-wall PIV measurements include generating a homogeneous global seeding that makes it possible to study both plume and entraining region, as well as optical problems due to near-surface laser reflection that makes the measurement process more complicated.

  • 8.
    Sattari, Amir
    et al.
    University of Gävle, Gävle, Sweden.
    Fallenius, Bengt
    The Royal Institute of Technology (KTH), Stockholm, Sweden.
    Fransson, Jens H. M.
    The Royal Institute of Technology (KTH), Stockholm, Sweden.
    Sandberg, M.
    University of Gävle, Gävle, Sweden.
    PIV Visualisation study in a two-dimensional room model with rapid time varying ventilation flow rates2011Inngår i: Roomvent 2011: proceedings / [ed] Vojislav Novakovic, Sten Olaf Hanssen, Hans Martin Mathisen, Tapir Academic Press , 2011Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Optimal control of inlet jet flows is of wide applicative interest in order to enhance mixing and reduce stagnation in a ventilated room. The general approach in mechanical ventilation is to use a constant flow rate forced convection system providing the ventilation air. This type of ventilation may cause several problems such as draught, stagnation at certain occupied locations, and subsequently low ventilation efficiencies. An alternative to increase the ventilation quality that has been of interest in this study is to introduce flow variations, which is considered as a potential to reduce stagnation and increase efficiency of the ventilation. The study was conducted as a model experiment in a small-scale, two-dimensional (2-D) room model with dimensions 30200.9 cm3 with water as operating fluid. The size of the model made it possible to investigate the 2-D velocity vector field within the entire room using Particle Image Velocimetry (PIV) method and further consequent dynamical and statistical analyses have been done from the resulted PIV vector fields. The comparison between cases of constant flow rate and flow variations have been conducted for the cases of two set of base flow rates and for each one, the cases of constant flow rate and flow variations with frequencies of 0.3, 0.4 and 0.5 Hz, is considered. In this investigation we show that the calm region, with a large stagnation zone, without pulsating inflow condition becomes more active in the sense that the stagnation points are moved and that the small-scale structures are grown for increasing pulsation frequency.

  • 9.
    Sattari, Amir
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Sandberg, Mats
    Particle Image Velocimetry (PIV) visualization of air flow over a wall-mounted radiator2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A common room heating technique is to use a wall-mounted radiator without forced convection. The cold surrounding air passes adjacent to the warm surfaces of the radiator, gets heated, and the buoyancy difference gives this heated air a momentum to rise along the wall surface (as plume) and finally circulate and get mixed into the whole room. The properties of heated plumes are important for assessing the risk of soiling of the wall surfaces through particle deposition driven by thermophoresis and turbophoresis. It is important to identify where there is a transition from laminar to turbulent flow. With the objective to characterize the plume of heated air flow in the vicinity of wall surface, the airflow over the radiator is visualized and measured using the two-dimensional Particle Image Velocimetry (2D PIV) technique. The PIV technique yields two-dimensional vector fields of the flow. The resulted vector maps are size and peak validated and post processed using in house developed software to provide the average streamlines. In the near wall PIV measurements there are practical problems; generating a homogeneous global seeding that makes it possible to study both the plume and the surrounding entrainment region, and optical problems due to strong laser reflection from the wall surface which limits the investigation area. These issues are dealt with in the present study. In addition to visualization with PIV, visualization with a CMOS video camera was also conducted.

  • 10.
    Susha, Iryna
    Örebro universitet, Handelshögskolan vid Örebro Universitet.
    The digital citizen as partner in eGovernance: ambitions and institutional realities2013Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This cover paper summarizes the research conducted in the period from June 2011 to January 2013 as part of PhD work. It belongs to the field of eParticipation, often considered to be a sub-domain of the eGovernment field. More generally, eParticipation stands for citizens’ participation in the processes of public service provision at its various stages. It is not limited to activities involving government but also includes bottom-up citizen participation like social networking, blogging, video sharing etc. The focus of this thesis is government-initiated eParticipation activities. The rationale for focusing on government-owned channels of eParticipation is that they, unlike e.g. opinion formation in social networks, normally have a direct link to the formal process of decision-making. This means that the citizens’ input provided via government-managed eParticipation tools would be expected to be formally processed by the government and integrated in some way into the policy-making activities.

    The status of government-initiated eParticipation is not impressive by any standards; regardless of numerous trials and gradual progress, governments still use the new media in their interaction with the public in a quite tentative manner. This occurs against the background of the rapidly changing communication landscape, such as the rise of the social Internet, which governments need to embrace in order to catch up with the public and stay relevant to their citizens. Therefore this research asks the question: how do governments handle the challenge of delivering more and better eParticipation? By "more and better eParticipation" is meant including forms of participation which utilise state-of-the-art communication technology as well as enhancing the role and influence of the citizenry in the decision-making process. "Digital citizen as partner" is the conceptual framing of such enhanced presence and leverage of the wider public in the democratic affairs of the state. In sum, this research looks into the development practice of ambitious eParticipation activities with the view of understanding how – with what degree of success and failure, and why – governments implement this change.

    The research is based on the analysis of a single project using case-study methodology. The selected case is the European Citizens’ Initiative (ECI), which was launched on April 1, 2012. It was bound to become the first trans-European agenda-setting mechanism; 1 million citizens can by signing an initiative propose a new EU law. Of particular interest in this study was the eParticipation element in this project, namely the online collection of statements of support across EU. Hence the research inquired into how this technological component was shaped by the institutional forces, including organisational behaviour, institutional logics, political agendas, regulatory frameworks etc. The research refers to such theories as systems view (dimensions of eDemocracy shaping, dynamic socio-technical eGovernance system); political value perspective (models of eDemocracy, values in participatory policy-making); stakeholder analysis (genre taxonomy to capture perceptions). The research is reported in three research publications, including a literature review of eParticipation (Paper 1), a conceptual study of the case (Paper 2), and an empirical investigation of the start-up phase of the project (Paper 3). The fieldwork included document studies, interviews, and observations carried out in the period of March through August 2012 in EU institutions in Brussels.

    The main findings of the case study can be summarised as follows: in its initial configuration the ECI created major constraints to effective citizen participation online. This was due to the disproportionate requirements for using the procedure, such as for example expensive system setup and liability for data breaches. The root cause, as the analysis of policy-makers’ rationales showed, lay in the way the tool was designed. This in turn could be traced to the institutions’ failure to handle the socio-technical complexity of the eParticipation procedure, i.e. focusing on the technical solution without properly considering the social environment of its use. The research proposes a number of measures which can be conducive to more effective eParticipation design, such as for instance enabling genuine collaboration with external stakeholders and seizing opportunities for learning and adjustment in the organisational setup of public institutions. In general the conclusion is that the strategic and operational sides of developing eParticipation need better alignment; a visionary eDemocracy idea like the ECI would require a more entrepreneurial attitude and processes within government to implement it effectively.

    The contributions of this research are relevant both for the practice and theory of eParticipation development. In the practical dimension this research shows how the design – understood broadly as the regulatory framework governing the use of the tool – which is conditional on internal institutional variables, can affect eParticipation. Therefore understanding the attitudes and actions of the ‘insiders’ – politicians, public officials, technologists – can be crucial for developing ICT-supported democratic procedures. Such focus on the collective mental models of decision-makers regarding eParticipation is not quite common in eParticipation research and practice which makes this thesis particularly relevant. In relation to theory this cover paper also has important implications – it addresses a gap in the eParticipation literature concerning the changing role and behaviour of traditional public institutions under the conditions of new media and the transforming relationship with the increasingly more digital citizenry. The research also puts an eParticipation case against the background of eGovernance by applying a model therefrom (a dynamic socio-technical view of eGovernance) onto the development of the ECI as an eParticipation opportunity. By doing so the cover paper tests the model and further elaborates on the interaction between the social and technical dimensions using the case as an illustration.

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