39 research outputs found

    Adaptive GPU-accelerated force calculation for interactive rigid molecular docking using haptics

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    Molecular docking systems model and simulate in silico the interactions of intermolecular binding. Haptics-assisted docking enables the user to interact with the simulation via their sense of touch but a stringent time constraint on the computation of forces is imposed due to the sensitivity of the human haptic system. To simulate high fidelity smooth and stable feedback the haptic feedback loop should run at rates of 500 Hz to 1 kHz. We present an adaptive force calculation approach that can be executed in parallel on a wide range of Graphics Processing Units (GPUs) for interactive haptics-assisted docking with wider applicability to molecular simulations. Prior to the interactive session either a regular grid or an octree is selected according to the available GPU memory to determine the set of interatomic interactions within a cutoff distance. The total force is then calculated from this set. The approach can achieve force updates in less than 2 ms for molecular structures comprising hundreds of thousands of atoms each, with performance improvements of up to 90 times the speed of current CPU-based force calculation approaches used in interactive docking. Furthermore, it overcomes several computational limitations of previous approaches such as pre-computed force grids, and could potentially be used to model receptor flexibility at haptic refresh rates

    Helpdesking: Knowing and learning in IT support practices

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    The background of this doctoral thesis is an interest in work achievement over extended time periods in specialized and technology-infused workplaces. Globalization, digitalization and increased focus on customer services are constituent aspects that have been claimed responsible for the current changes in the way work practices and teamwork are organized. In IT helpdesk work, which is the object of study in this thesis, challenges including dissemination of information, keeping up-to-date with technological changes and coordi- nation of people and tasks have been identified as critical. The aim of this thesis is to illuminate how knowing and competence are maintained and shared as participants engage in backstage activities in helpdesk work. The focus is on the nature of the activities that unfolds when employees engage in activities that include interaction as well as artefacts. The empirical material comprises video- and audio-recorded activities of a second-level helpdesk in a large multinational IT provider. Targeted ‘hot spot’ activities are shift changes, quality discussions and introductions of newcomers. Based on a sociocultural perspective, the (re)production of professional practices is understood as continuous negotiations between participants and tools within a situated framework. Methodologically, this implies detailed investigations of authentic activities where interactions and tool use are analysed from the participant’s perspective. Three studies are included in the thesis, each of them provide insights into the organizing of shared knowing and competence. Study One focuses on how tasks and information are communicated between shifts and transformed into workable units and knowledge. Study Two addresses the role of activities specifically arranged for learning and separated from other work tasks. In Study Three, the focus is on introductions of newcomers and what can be learned from interactions with experienced participants and technological tools. The analyses show that knowledge work is a continuous and communicatively-based undertaking. Continuity across shifts relies on several documenting routines and procedures, but shift change meetings provide opportunities for interpretation and negotiation of information as well as coordination of tasks. Talking about work provides a space for reflection and reformulation of team-related quality norms and values as shared foundations for work. Furthermore, inducting newcomers to the specialized and situated practice brings about the very detailed procedures involved in managing everyday work and technological tools. By describing the reasoning and knowing displayed by helpdesk employees, the thesis contributes to discussions about knowledge work and sharing in organizational settings, teamwork, system design and lifelong learning. To conclude, it is suggested that sharing and reproduction of knowing in practice is a collective effort that entails creative involvement by members of the practice

    Petter Bivall Cover Image: Homage to the Helix

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    Copyright © 2010 Petter Bivall, unless otherwise noted. The following copyright statement applies to figures 2.4, 4.2, 5.1 & 5.3: © 2010 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Printed by LiU-Tryck, Linköping 2010 Communicating the content of molecular life science is a challenge that educators and researchers face on a daily basis. The complexity of this communication arises partly because molecular events occur at a scale of both size and time which is not perceivable to humans, and partly from the multiple and stochastic interactions involved in those events. This dissertation presents research investigating the development and use of a combined visual and haptic virtual model in higher education. The model presents molecular recognition through the example of protein-ligand docking, and enables students to simultaneousl

    Learning Molecular Interaction Concepts through Haptic Protein Visualization

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    Abstract The use of haptics is growing in the area of science education. Haptics appears to convey information to students in a manner that influences their learning and ways of thinking. This document outlines examples of how haptics has been employed in science education contexts and gives a more detailed description of an education oriented evaluation of a haptic protein-ligand docking system. In molecular life science, students need to grasp several complex concepts to understand molecular interactions. Research on how haptics influences students' learning show strong positive affective responses and, in the protein-ligand docking case, that reasoning with respect to molecular processes is altered. However, since many implications of using haptics in education are still unknown, more research is needed

    Touching the Essence of Life : Haptic Virtual Proteins for Learning

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    This dissertation presents research in the development and use of a multi-modal visual and haptic virtual model in higher education. The model, named Chemical Force Feedback (CFF), represents molecular recognition through the example of protein-ligand docking, and enables students to simultaneously see and feel representations of the protein and ligand molecules and their force interactions. The research efforts have been divided between educational research aspects and development of haptic feedback techniques. The CFF model was evaluated in situ through multiple data-collections in a university course on molecular interactions. To isolate possible influences of haptics on learning, half of the students ran CFF with haptics, and the others used the equipment with force feedback disabled. Pre- and post-tests showed a significant learning gain for all students. A particular influence of haptics was found on students reasoning, discovered through an open-ended written probe where students' responses contained elaborate descriptions of the molecular recognition process. Students' interactions with the system were analyzed using customized information visualization tools. Analysis revealed differences between the groups, for example, in their use of visual representations on offer, and in how they moved the ligand molecule. Differences in representational and interactive behaviours showed relationships with aspects of the learning outcomes. The CFF model was improved in an iterative evaluation and development process. A focus was placed on force model design, where one significant challenge was in conveying information from data with large force differences, ranging from very weak interactions to extreme forces generated when atoms collide. Therefore, a History Dependent Transfer Function (HDTF) was designed which adapts the translation of forces derived from the data to output forces according to the properties of the recently derived forces. Evaluation revealed that the HDTF improves the ability to haptically detect features in volumetric data with large force ranges. To further enable force models with high fidelity, an investigation was conducted to determine the perceptual Just Noticeable Difference (JND) in force for detection of interfaces between features in volumetric data. Results showed that JNDs vary depending on the magnitude of the forces in the volume and depending on where in the workspace the data is presented

    ”Knöligt men vĂ€rdefullt” : en utvĂ€rderingsrapport om samverkan i ett multiprofessionellt, tvĂ€rsektoriellt innovationsprojekt

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    Idag pĂ„gĂ„r omfattande satsningar pĂ„ innovationsprojekt inom offentlig sektor dĂ€r mĂ„let Ă€r genomgripande förĂ€ndringar och nytĂ€nk pĂ„ individ- och samhĂ€llsnivĂ„. Innovationsprojekt av detta slag karaktĂ€riseras av skapandet av nya samarbeten och samverkansaktiviteter inom offentlig sektor men ocksĂ„ med privat sektor och akademi. BĂ€ttre folkhĂ€lsa genom skolframgĂ„ng Ă€r ett Vinnova-finansierat samverkansprojekt med visionen att bidra till ett ökat och förbĂ€ttrat folkhĂ€lsoarbete genom ett fokus pĂ„ barn och unga och genom att hjĂ€lpa elever till ett bĂ€ttre skolresultat. Projektets utgĂ„ngspunkt var analyser av stora datamĂ€ngder, sĂ„ kallade ”big data”-analyser, i en tvĂ€rsektoriell och tvĂ€rprofessionell projektgrupp. Denna rapport redogör för resultatet av den beteendevetenskapligt inriktade utvĂ€rdering som gjorts, dĂ€r syftet var att analysera samverkan och samarbete inom projektet. Den utgĂ„r frĂ„n deltagarnas upplevelser och erfarenheter av att delta i projektarbetet och belyser bĂ„de framgĂ„ngsrika och försvĂ„rande förhĂ„llanden under projektets genomförande.  Intervjuer med nio projektdeltagare som genomfördes i maj och juni 2019 ligger till grund för analysen. DĂ€rutöver har samtal förts med projektledaren som ett sĂ€tt att skapa förstĂ„else för projektets struktur och genomförande jĂ€mte projektets interna dokumentation. Resultatet visade att innovationsarbetet inneburit en viss förflyttning av projektfokus frĂ„n en ursprunglig visionĂ€r instĂ€llning baserat i en ”big data”-approach för förbĂ€ttrade skolresultat och verksamhetsförĂ€ndring till en mer operationaliserbar mjukvaruutveckling av verktyg för att hantera och förebygga skolfrĂ„nvaro. Projektgruppens breda kunskapsbas, dĂ€r olika professionella kompetenser samverkade, fick betydelse för projektets möjligheter att formulera innovativa idĂ©er och göra nĂ„got nytt. Kontinuerliga möten och dialog mellan deltagare var centrala för ett gemensamt skapande av projektmĂ„l och -riktning. Antalet projektparters problematiserades samtidigt dĂ„ bredden av perspektiv i viss mĂ„n försvĂ„rade möjligheten att driva projektet framĂ„t. Projektets utveckling och riktning pĂ„verkades Ă€ven av att nya projektmedlemmar tillkom och andra försvann, som exempelvis initiativtagare och ursprunglig projektledare. Projektets breda innovativa idĂ© och angreppsĂ€tt innebar att deltagarna i huvudsak uppfattade projektet som dels ett forskningsprojekt och dels ett mjukvaruutvecklingsprojekt. Relationen dem emellan tycktes delvis oklar, med frĂ„gor om pĂ„ vilka sĂ€tt de förvĂ€ntades förhĂ„lla sig till varandra. Det datadrivna arbetet gav upphov till etiska och juridiska spörsmĂ„l men aktualiserade ocksĂ„ frĂ„gan om den inbördes relationen mellan forskning och produktutveckling. En stark verksamhetsanknytning och kontakt med lĂ€rare och skola sĂ„gs som centralt för projektresultatets relevans inom skolan. Uteblivna kontakter med kontinuerliga lĂ€rargrupper och skolledare över tid pĂ„ grund av organisatoriska hinder försvĂ„rade dock ett konstruktivt och iterativt utvecklingsarbete. Det blev inte heller möjligt att genomföra verksamhetsövergripande förĂ€ndringsarbete. Slutsatser som lyfts fram Ă€r att breda innovationsprojekt av verksamhetförĂ€ndrande karaktĂ€r stĂ€ller stora krav pĂ„ projektorganisering och en tydligt delad mĂ„lbild av gruppen. Komplexiteten i den hĂ€r typen av innovationsprojekt ökar ju fler samverkansparter dĂ€r ingĂ„r som ska enas om ett gemensamt syn- och angreppssĂ€tt pĂ„ innovationens genomförande. En bredd av professionell kunskap och erfarenhet som strĂ€cker sig över privata företag, offentlig förvaltning och akademi/institut ger utrymme för att finna nya innovativa lösningar men samarbetsmöjligheterna försvĂ„ras ocksĂ„. Valet av vilka kompetenser som behövs för att skapa och genomföra innovationen behöver stĂ€llas mot antalet projektparter dĂ„ fler inspel inte nödvĂ€ndigtvis leder till bĂ€ttre kvalitet i slutresultatet. Innovationsinsatser som sker i samverkan mellan olika aktörer, sĂ„vĂ€l privata som offentliga, krĂ€ver nĂ„gon eller nĂ„gra sammanhĂ„llande krafter som kan processleda helheten och som kontinuerligt kommunicerar med styrgruppen och arbetsgrupperna. DĂ€rtill behövs mötesarenor för dialog mellan projektdeltagare i projektets olika delar om ambitionen Ă€r att arbeta fram en sammanhĂ„llen innovation med stort inflytande för innovationsvisionen. Den eller de som ska hĂ„lla samman behöver fĂ„ eller skapa förutsĂ€ttningar för att kunna göra det. Slutligen lyfts att skolans och lĂ€rarnas behov och intresse av innovationen i den riktning projektet tagit med att fokusera pĂ„ produktutveckling av nĂ€rvarorelaterade system endast framgĂ„r som andrahandsberĂ€ttelser i den hĂ€r utvĂ€rderingen. UtifrĂ„n ett samverkansperspektiv framstĂ„r det dock tydligt att skolan som samverkanspart Ă€r grundlĂ€ggande för att Ă„stadkomma de relevanta och stödjande it-system som projektet arbetar för och Ă€ven för att Ă„stadkomma en genomgripande verksamhetsutveckling.

    Skyddsvallar mot översvÀmning runt Kristianstad

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    KlimatförĂ€ndringar Ă€r ett allvarligt problem som vi behöver ta ansvar för. NĂ€r temperaturen ökar i luften ökar Ă€ven temperaturen i havet vilket orsakar att vattnet expanderar, isarna smĂ€lter och vi fĂ„r kraftigare skyfall. DessvĂ€rre hinner vi inte stoppa sjĂ€lva klimatförĂ€ndringarna innan vi pĂ„verkas av de höga vattennivĂ„erna och vattenflödena som blivit följden av klimatförĂ€ndringarna. DĂ€remot kan vi klimatanpassa och förbereda vĂ„ra samhĂ€llen för klimatförĂ€ndringarna som berĂ€knas upptrĂ€da. Syftet med arbetet har varit att ge en överblick över Kristianstad kommuns klimatanpassningsĂ„tgĂ€rder för att skydda staden mot översvĂ€mningar. Syftet har Ă€ven varit att utreda om och pĂ„ vilka sĂ€tt de befintliga översvĂ€mningsskydden i staden erbjuder eller skulle kunna erbjuda fler funktioner Ă€n att endast stoppa översvĂ€mningar. Arbetet baserades frĂ€mst pĂ„ en litteraturstudie och observation. Först utfördes en litteraturstudie för att undersöka om översvĂ€mningsskydden fyller den primĂ€ra funktionen, dĂ€refter utfördes en observation för att undersöka om det fanns sekundĂ€ra funktioner vid anlĂ€ggningarna. Resultatet frĂ„n litteraturstudien visar att Kristianstad frĂ€mst anvĂ€nder skyddsvallar och pumpstationer som översvĂ€mningsskydd. DĂ€remot behöver Kristianstad vidta fler klimatanpassningsĂ„tgĂ€rder för att skydda staden mot översvĂ€mningar pĂ„ lĂ„ng sikt. Resultatet frĂ„n observationen visar att det finns sekundĂ€ra funktioner vid skyddsvallarna, frĂ€mst i form av gĂ„ngvĂ€gar ovanpĂ„ skyddsvallens krön. Slutsatserna i denna studie Ă€r att Kristianstad kommun har god beredskap för höga vattenstĂ„nd och vattenflöden. Det kan Ă€ven konstateras att det finns sekundĂ€ra funktioner vid skyddsvallarna, frĂ€mst i form av gĂ„ngvĂ€gar. Men det skulle vara mer anvĂ€ndbart om man skapade fler sekundĂ€ra funktioner som bidrar till rekreation, biologisk mĂ„ngfald och andra vistelsevĂ€rden.Climate change is a serious problem that we need to take responsibility for. As the temperature increases in the air, the temperature in the ocean also increases, causing the water to expand and ice to melt. There will also be more intense rainfall. Unfortunately, we can’t stop the climate change itself before we are affected by the high-water levels and flows that have resulted from the climate change. However, we can adapt to the climate and prepare our communities for the expected effects of climate change. The purpose of this work has been to provide an overview of Kristianstad municipality’s climate adaption measures to protect the city against flooding. The purpose has also been to investigate whether and in what ways the existing flood protection in the city offers and could offer more functions than just preventing flooding. The work was primarily based on a literature study and observation. First, a literature study was conducted to investigate if the flood protections serve their primary function, and then an observation was performed to investigate the presence of secondary functions at the facilities. The results from the literature study indicate that Kristianstad primarily utilizes protective embankments and pumping stations as flood protection measures. However, Kristianstad needs to implement more climate adaption measures to safeguard the city against flooding in the long run. The results from the observation show that there are secondary functions associated with the protective embankment, primarily in the form of pedestrian walkways on top of the embankment crests. The conclusions drawn from this study are that the municipality of Kristianstad is well-prepared for high water levels and water flows. It can also be noted that there are secondary functions present at the protective embankments, primarily in the form of pedestrian walkways. However, it would be more useful to create more secondary functions that contribute to recreation, biodiversity, and other amenities

    Haptic Just Noticeable Difference in Continuous Probing of Volume Data

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    Just noticeable difference (JND) describes how much two perceptual sensory inputs must differ in order to be distinguishable from each other. Knowledge of the JND is vital when two features in a dataset are to be separably represented. JND has received a lot of attention in haptic research and this study makes a contribution to the field by determining JNDs during users' probing of volumetric data at two force levels. We also investigated whether these JNDs were affected by where in the haptic workspace the probing occurred. Reference force magnitudes were 0.1 N and 0.8 N, and the volume data was presented in rectangular blocks positioned at the eight corners of a cube 10 cm3 in size. Results showed that the JNDs varied significantly for the two force levels, with mean values of 38.5% and 8.8% obtained for the 0.1 N and 0.8 N levels, respectively, and that the JND was influenced by where the data was positioned
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