| 1. |
- Ljung, Robert, et al.
(författare)
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Poor listening conditions impair memory for intelligible lectures : implications for acoustic cassroom standards
- 2009
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Ingår i: Building Acoustics. - : SAGE Publications. - 1351-010X .- 2059-8025. ; 16:3, s. 257-265
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports two experiments on the effects of degraded speech signals on memory for spoken lectures. Experiment 1 showed that broadband noise impairs university students' memory for a spoken lecture, even though the participants heard what was said. Experiment 2 showed that reverberation has detrimental effects to school adolescents' memory for spoken lectures, similar to broadband noise. The results suggest that poor listening conditions (resulting from background noise and/or long reverberation time) impair memory and learning, even if the conditions allow the listeners to hear what is said. Since the goal for students and pupils attending to lectures is to remember the lecture rather than just hearing what is said, the results presented here indicate that standards for acceptable signal-to-noise ratios and reverberation times in buildings designed for learning should consider the distinction between speech intelligibility and memory. Standards should be based on memory criteria instead of intelligibility criteria.
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| 2. |
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| 3. |
- Elfström, Peter, 1974-
(författare)
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Associated disorders in celiac disease
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Celiac disease (CD) is an autoimmune disorder that affects genetically susceptible individuals and is induced by dietary gluten. Treatment consists of a lifelong gluten-free diet. CD is common and affects about 1% of the general population. The classic symptoms include diarrhea and malabsorption, but many patients have only mild symptoms or no symptoms at all. The proportion of individuals presenting with atypical symptoms or discovered only when investigating an associated condition of CD is increasing. Aims: The aim of this thesis was to investigate the risk of possible associated disorders through Swedish population-based registers. The objective was to gain more information on the consequences of having CD and to identify high risk groups where screening may be considered. Materials and methods: We used the Swedish hospital discharge register to examine the risk of liver disease, autoimmune heart disease, Addison’s disease and thyroid disorders in a cohort of about 14,000 individuals with CD and an age and sex matched reference population of 70,000 individuals. In the last study we used all regional pathology registers and the cancer registry to examine the risk of hematopoietic cancer, including lymphoma in three different cohorts: I) 28,810 individuals with CD; II) 12,681 individuals with small intestinal mucosal inflammation but without villous atrophy; and III) 3552 individuals with latent CD (a positive serology test for CD with a normal small intestinal biopsy). Results: CD is statistically significantly associated with an increased risk of liver disease, Addison’s disease, thyroid disease and lymphoma. We also found an increased risk of lymphoma in individuals with small intestinal mucosal inflammation. There was no statistically significant association between autoimmune heart disease or leukemia and CD. Latent CD was not associated with any hematopoietic cancers. Conclusion: This thesis found a positive association between CD and a number of autoimmune and inflammatory disorders. Clinicians need to have a high awareness of this association and to test for these conditions when symptoms appear.
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| 4. |
- Green, Anders
(författare)
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Characterising dimensions of use for designing adaptive dialogues for human-robot communication
- 2007
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Ingår i: 2007 RO-MAN. - 9781424416349 ; , s. 1071-1076
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Konferensbidrag (refereegranskat)abstract
- In this paper we provide a possible characterisation of user behaviour based on an analysis of a corpus of human-robot communication, collected by using the Wizard-of-Oz technique to elicit communicative behaviour. We distinguish between three general types of user behaviour: uniform user behaviour, idiosyncratic user behaviour and distinguishing user behaviour. We also present an analysis of user behaviour that can be characterized in terms of overall task organisation (i.e., interaction episodes) and behaviour that is intimately connected to communicative behaviour. We also discuss to what extent manipulation of objects to prepare the environment can be used to group users along the dimensions: task- vs. interaction-orientation and control vs. monitoring. Using this typology we discuss categorisation into four dimensions of use: Directors, Manipulators, Pointers and Players. To support these use dimensions we propose a set of adaptation foci (Focus on Feedback or Action, and on Proactive or Reactive behaviour).
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| 5. |
- Green, Anders, 1971-
(författare)
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Designing and Evaluating Human-Robot Communication : Informing Design through Analysis of User Interaction
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis explores the design and evaluation of human-robot communication for service robots that use natural language to interact with people. The research is centred around three themes: design of human-robot communication; evaluation of miscommunication in human-robot communication; and the analysis of spatial influence as empiric phenomenon and design element. The method has been to put users in situations of future use through means of Hi-fi simulation. Several scenarios were enacted using the Wizard-of-Oz technique: a robot intended for fetch- and carry services in an office environment; and a robot acting in what can be characterised as a home tour, where the user teaches objects and locations to the robot. Using these scenarios a corpus of human-robot communication was developed and analysed. The analysis of the communicative behaviours led to the following observations: the users communicate with the robot in order to solve a main task goal. In order to fulfil this goal they overtake service actions that the robot is incapable of. Once users have understood that the robot is capable of performing actions, they explore its capabilities. During the interactions the users continuously monitor the behaviour of the robot, attempting to elicit feedback or to draw its perceptual attention to the users’ communicative behaviour. Information related to the communicative status of the robot seems to have a fundamental impact on the quality of interaction. Large portions of the miscommunication that occurs in the analysed scenarios can be attributed to ill-timed, lacking or irrelevant feedback from the robot. The analysis of the corpus data also showed that the users’ spatial behaviour seemed to be influenced by the robot’s communicative behaviour, embodiment and positioning. This means that we in robot design can consider the use strategies for spatial prompting to influence the users’ spatial behaviour. The understanding of the importance of continuously providing information of the communicative status of the robot to it’s users leaves us with an intriguing design challenge for the future: When designing communication for a service robot we need to design communication for the robot work tasks; and simultaneously, provide information based on the systems communicative status to continuously make users aware of the robots communicative capability.
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| 6. |
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| 7. |
- Green, Anders, et al.
(författare)
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Developing a Contextualized Multimodal Corpus for Human-Robot Interaction
- 2006
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Ingår i: Proceedings of the fifth international conference on language resources and evaluation. ; , s. 401-406
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Konferensbidrag (refereegranskat)abstract
- This paper describes the development process of a contextualized corpus for research on Human-Robot Communication. The data have been collected in two Wizard-of-Oz user studies performedwith 22 and 5 users respectively in a scenario that is called the HomeTour. In this scenario the users show the environment (a single room, or a whole floor) to the robot using a combination of speech and gestures. The corpus has been transcribed and annotated with respect to gestures and conversational acts, thus forming a core annotation. We have also annotated or linked other types of data, e.g., laser range finder readings, positioning analysis, questionnaire data and task descriptions that form the annotated context of the scenario. By providing a rich set of different annotated data, thecorpus is thus an important resource both for research on natural language speech interfaces for robots and for research on human-robot communication in general.
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| 8. |
- Green, Anders
(författare)
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Fotboll och huliganism : Utveckling, problem och åtgärdsarbete i England och Skandinavien
- 2009
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Rapport (refereegranskat)abstract
- Förord Nu är det dags att avsluta mina år som doktorand, vilket sker med ett arbete om fotboll ochhuliganism. Det hela började med att jag hade ett, som vanligt, stimulerande samtal med professorLeif Lenke under vilket vi bland annat diskuterade mina möjligheter att skriva en licentiatuppsatspå ett material om långtidsdömda fångar. Sin vana trogen var Leif positiv och jagantogs som ofinansierad doktorand. Sannolikt med något ord på vägen från Leif, som tyvärravled under fjolåret. Tack, Leif!Det blev alltså inte en fängelsestudie. Inte heller kom min uppsats att handla om närpolisarbete,som var min idé under en period. Att det blev fotboll och huliganism skall min fru Ceciliatackas för. Efter ett inslag om huliganism på TV-nyheterna sade hon att det väl vore ett lämpligtämne för mig att forska om, inte minst då jag har fotbollsintresset. Hmm, sade jag direkt,men gillade allteftersom idén. Ganska snart tog jag kontakt med Lennart Petersson (dåvarandekommissarie på RPS, numera säkerhetsansvarig på SvFF) som var polisen som yttrat sig i TV.Genom hans välvilja kom jag i kontakt med generalsekreteraren i SvFF, Sune Hellströmer.Via stiftelsen ’Älska fotboll’ erhöll jag finansiering i två omgångar, vilket jag är väldigt tacksamför. Inte bara för forskningen i sig, utan även den möjlighet jag fått att få komma in”bakom elitfotbollens kulisser”. I synnerhet resorna till England var lite som att mina pojkdrömmarbesannades. Lennart och Sune, stort tack för det goda bemötandet, att ni trodde påmina projekt och ”dörröppnandet”.Vidare vill jag också rikta ett tack till NSfK (Nordiska Samarbetsrådet för Kriminologi) somfinansierade den skandinaviska delstudien.Under detta arbete har jag kommit i kontakt med många personer. Inledningsvis vill jag riktamitt tackande till de säkerhetsansvariga och supporterpoliser som ställt upp på intervjuer. Attses på möten, utbildningar etc. är riktigt givande och känns som en bekräftelse på att vi har enkonstruktiv dialog, som jag hoppas kan fortgå. Ett extra tack går till Hans Löfdahl, chef försupporterpoliserna i Stockholm, för manusläsningen.Gällande England vill jag rikta särskilda tack till några personer: Chris Whalley, säkerhetschefvid engelska FA, som var min värd vid den första Englands-resan i februari 2006. BryanDrew och Tony Conniford, vid UKFPU, som inte bara tog sig tid för möten utan även hjälptemig med att komma i kontakt med poliser som Keith, Karl, Scott, Warren, Jason, Shirley,John m.fl. till vilka också ett tack skall riktas. Inte minst tackar jag för den tid ni avsatte för atthjälpa mig. Good on you and cheers for all the help I’ve got!I de skandinaviska grannländerna vill jag särskilt tacka Morten Løw Hansen vid Oslo Sentralpoliti.Detsamma gäller Lars Ruby och Henrik Kjaer Jensen vid Rigspolitiet i Köpenhamn.Utöver god hjälp i era respektive länder har ni blivit goda vänner, som håller kontakten ochsom det alltid är givande att träffa.Huliganism ur ordningshållande perspektiv har passat väl inom mitt arbete på Polishögskolan(PHS) och jag har fått flera kollegor inom det polistaktiska arbetet. Tack, alla taktikare, för ertvisade intresse och era uppmuntrande ord. Ett par särskilda tack vill jag rikta till förre studierektornMarianne Hilton och fil.dr. Lars Dolmén. Utöver att ni stöttade mitt arbete och sågnyttan av det inom polisens utbildningar och verksamhet var ni även överseende med att jagunderstundom skrev på denna uppsats. Till PHS bibliotek, och till Maria Perényi i synnerhet,riktas ett stort tack för all hjälp med materialsökande.Professor Janne Flyghed har fungerat som min handledare. Jag är medveten om att mina texterofta präglas av bisatser och stickspår, men du har med noggrannhet tagit dig igenom dem.Allteftersom framväxte mer stringens och tydlighet i manuset och för detta skall du tillskrivasrätt stor ära. Tack, Janne! Framöver kan kanske våra samtal vara helt fotbollsfokuserade…Även om jag inte rent fysiskt har varit närvarande på Kriminologiska institutionen så oftakänner jag mig hemma där, vilket jag redan gjorde under 1980-talets slut då jag läste mitt förstabetyg i ämnet. Då jag kommer förbi finns det alltid någon att luncha med eller bara pratamed och få ventilera lite skrivarvånda. Tack riktas till alla som kan och vill känna sig träffade.Ingen nämnd och heller ingen glömd. Som en avslutning på detta kriminologiska kapitel villjag också passa på att tacka fil.dr. Helena du Rees som var kommentator vid mitt slutseminariumsamt de övriga som bidrog med synpunkter.Utöver nämnda personer finns det fler som jag lärt känna under arbetets gång och som uppmuntratmig och visat intresse för min forskning. Ett nästsista ”öppet tack” går till er som kankänna att ni passar in på denna beskrivning.Mina slutliga tackord riktas givetvis till min familj; Cecilia samt Vera och Jacob. Ni har ju, pågoda grunder, frågat er om jag någonsin blir klar. Trots att jag själv emellanåt tvivlat svaradejag oförtrutet ja på er fråga, och äntligen är det sant. Från och med nu skall jag inte hela tidenförsvinna in i arbetsrummet! Vi kan kanske få loss lite tid för en fotbollsresa till England…
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| 9. |
- Green, Anders, et al.
(författare)
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Integrating miscommunication analysis in natural language interface design for a service robot
- 2006
-
Ingår i: 2006 IEEE/RSJ International Conference on Intelligent Robots and Systems, Vols 1-12. - NEW YORK : IEEE. - 9781424402588 ; , s. 4678-4683
-
Konferensbidrag (refereegranskat)abstract
- Natural language user interfaces for robots with cognitive capabilities should be designed to reduce the occurrence of miscommunication in order to be perceived as providing a smooth and intuitive interaction to its users. This paper describes how miscommunication analysis is integrated in the design process. Observations from 12 user sessions revealed that users misunderstand the robot's functionality; and that feedback sometimes is ill-timed with respect to the situation. We provide a set of design implications to prevent errors from occurring, to influence or adapt to users' behavior.
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| 10. |
- Green, Anders
(författare)
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The need for a model of contact and perception to support natural interactivity in human-robot communication
- 2007
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Ingår i: 2007 RO-MAN. - 9781424416349 ; , s. 551-556
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Konferensbidrag (refereegranskat)abstract
- In studies of human-robot communication we have observed that the robot's inability to give appropriate communicative feedback for contact and perception causes miscommunication [2]. The purpose of this paper is to motivate the need for and give air initial characterisation of a model for communicative contact and perception feedback. One component of a such a model could be a kind of low-level user model aiming to decide the perceptual status of the user. We have analysed an example of inter-action that shows signs of miscommunication that is related to feedback problems concerning contact and perception. Using the analysis to pinpoint the source. of these problem,,; we provide tin initial account for the type of information sources that a low-level user that handles communicative contact and perception feedback should comprise. We also provide two design examples that in our view motivates this explorative effort.
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| 11. |
- Green, Anders
(författare)
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Towards a Minimal Interaction Scheme : Initial Observations on Gesture Repertoire and Communication Strategies
- 2009
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Ingår i: RO-MAN 2009. - NEW YORK : IEEE. - 9781424450800 ; , s. 903-908
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Konferensbidrag (refereegranskat)abstract
- This paper investigates a prototype of an interaction design for a flexible natural language user interface with a minimal set of gestures and natural language commands. The prototype is evaluated using a Hi-Fi simulation approach that allows the enactment of an interfaces that accommodates gesture and speech input for directive commands. In the scenario users were guiding a robot equipped with a camera and microphone through a simple maze. The data from six users were collected and subsequently analysed with respect to the users' communicative behavior. In the analysis of the data special consideration was given to the gesture repertoire. It was found that users, when presented with static images of gestures, added their own dynamic patterns. Furthermore the users appeared to give precedence to the deictic component of gestures that meant left/right. Users were also opportunistic meaning that when they could they used predefined goal points and let the robot use its autonomous navigation to find its way.
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| 12. |
- Green, Anders, 1971-, et al.
(författare)
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With a new helper comes new tasks mixed-initiative interaction for robot-assisted shopping
- 2009
-
Ingår i: IHRCMICA-2009 Improving Human-Robot Communication with Mixed-Initiative and Context-Awareness.
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Konferensbidrag (refereegranskat)abstract
- In the CommRob project1 we are investigating Robot Assisted Shopping. We are considering the effects on usability when allowing for mixed-initiative dialogue. It is noted that when adding a robotic assistant to a scenario that was previously involving only one agent, two new tasks are created: collaborative interaction, and learning an interface. Evaluation of mixed-initiative dialogue becomes complicated because it is not straightforward to separate the overall task performance from the attributes brought by mixed-initiative interaction.
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| 13. |
- Green, Mattias, 1971, et al.
(författare)
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Physical oceanography and water exchange in the Northern Kvark Strait
- 2006
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Ingår i: Continental Shelf Research. - : Elsevier BV. - 0278-4343. ; 26:6, s. 721-732
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Tidskriftsartikel (refereegranskat)abstract
- The Northern Kvark connects the very fresh Bothnian Bay to the slightly saltier Bothilian Sea in the northern Baltic Sea. Intense field experiments were made in the strait in May 2003 and October-December 2004 to describe the physical oceanography of the strait. Three different hydrographic regimes were identified and first-order analyses were made on each regime, neglecting friction, rotation, and horizontal gradients. The strait is shown to be barotropically blocked about 45% of the time. The rest of the time there is vertical stratification, which can be described either by two homogenous layers or by linear density and velocity profiles. The flows in the two stratified regimes are shown to be hydraulically controlled. (C) 2006 Elsevier Ltd. All rights reserved.
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| 14. |
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| 15. |
- Green-Pedersen, Christoffer, et al.
(författare)
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Politics within paths : trajectories of Danish and Swedish earnings-related pensions
- 2006
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Ingår i: Journal of European Social Policy. - : SAGE Publications. - 0958-9287 .- 1461-7269. ; 16:3, s. 245-258
-
Tidskriftsartikel (refereegranskat)abstract
- This article investigates earnings-related pension schemes in Denmark and Sweden with a focus on the last two decades. It takes the path dependency idea as its starting point and develops it further with regard to pension politics. In the Danish case, the article shows that existing funded, occupational pension schemes precluded a pay-as-you-go (PAYGO) solution for workers not already covered due to a 'reverse double payment problem'. Political attention centred instead on broadening the coverage of occupational schemes. The article demonstrates that the development of funded pension systems also shows a great deal of path dependency. In the Swedish case, we provide a detailed empirical investigation which shows how the double payment problem affects the positions of political parties, rather than the entire reform process. The study thus argues that the political parties were the crucial actors in the Swedish pension reform and that the path dependency facilitated a consensual reform process because it made irrelevant a more fundamental party political disagreement over the pension system.
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| 16. |
- Groth, Kristina, et al.
(författare)
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Team Meetings within Clinical Domains : Exploring the Use of Routines and Technical Support for Communication
- 2009
-
Ingår i: HUMAN-COMPUTER INTERACTION - INTERACT 2009, PT II, PROCEEDINGS. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 9783642036576 ; , s. 975-976
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Konferensbidrag (refereegranskat)abstract
- Today, it is common that a team of clinicians, from different disciplines, instead of one single doctor, care for a patient. This is especially true when it concerns more complicated diseases in highly specialised health care. Going from one doctor to a team of doctors raises new dimensions/problems/issues when deciding about the diagnosis and how to treat the patient. Instead of one person deciding, based on the information given from others, a group of people need to agree on a decision. How do the participants during such decision meetings argue for their experience and skill? What kind of technologies are available and how do they support the communication in the meeting? Måseide (2006), for example, focuses on how different forms of evidence influence and regulate the judgements and decisions of medical practitioners during such meetings. Groth et al. (2008), for example, focuses on the technology used during such meetings, with a focus on audio, video, and images.
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| 17. |
- Huettenrauch, Helge, et al.
(författare)
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Investigating spatial relationships in human-robot interaction
- 2006
-
Ingår i: IEEE/RSJ International Conference on Intelligent Robots and Systems. - NEW YORK, NY : IEEE. - 9781424402588 ; , s. 5052-5059, s. 5052-5059
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Konferensbidrag (refereegranskat)abstract
- Co-presence and embodied interaction are two fundamental characteristics of the command and control situation for service robots. This paper presents a study of spatial distances and orientation of a robot with respect to a human user in an experimental setting. Relevant concepts of spatiality from social interaction studies are introduced and related to Human-Robot Interaction (HRI). A Wizard-of-Oz study quantifies the observed spatial distances and spatial formations encountered. However, it is claimed that a simplistic parameterization and measurement of spatial interaction misses the dynamic character and might be counterproductive in the design of socially appropriate robots.
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| 18. |
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| 19. |
- Hüttenrauch, Helge, et al.
(författare)
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What's in the gap? : Interaction Transitions that make the HRI work
- 2006
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Ingår i: Proceedings of the 15th IEEE international symposium on robot and human interactive communication. - New York : IEEE. ; , s. 123-128
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper presents an in-depth analysis from a Human Robot Interaction (HRI) study on spatial positioning and interaction episode transitions. Subjects showed a living room to a robot to teach it new places and objects. This joint task was analyzed with respect to organizing strategies for interaction episodes. Noticing the importance of transitions between interaction episodes, small adaptive movements in posturewere observed. This finding needs to be incorporated into HRI modules that plan and execute robots’ spatial behavior in interaction, e.g., through dynamic adaptation of spatial formations and distances depending on interaction episode.
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| 20. |
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| 21. |
- Ljung, Robert, et al.
(författare)
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Memory of a text heard in noise
- 2008
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Ingår i: ICBEN 2008. - Dortmund : IfADo. - 9783980834254 ; , s. 450-453
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Konferensbidrag (refereegranskat)abstract
- When spoken information is presented in unfavourable listening conditions a larger part of the available and limited information processing resources must be allocated to the identification of the words spoken. This leaves fewer resources for the further processing of the speech (the interpretation and storing of the information). In such circumstances understanding and memory of speech might be impaired although each word has been correctly heard. This hypothesis was confirmed in two previous studies where memory of a word list was shown to be impaired when presented in unfavourable listening conditions: unfavourable signal/noise ratio (Kjellberg, Ljung & Hallman, 2008) and a too long reverberation time (Ljung & Kjellberg, in press). Kjellberg et al. also found that the noise effect was weaker the better the working memory capacity (as measured with a reading span task).
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| 22. |
- Lohse, M., et al.
(författare)
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Evaluating extrovert and introvert behaviour of a domestic robot – a video study
- 2008
-
Ingår i: Proceedings of the 17th IEEE International Symposium on Robot and Human Interactive Communication, RO-MAN. - New York : IEEE. - 9781424422128 ; , s. 488-493
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Konferensbidrag (refereegranskat)abstract
- Human-Robot Interaction (HRI) research is here presented into social robots that have to be able to interact with inexperienced users. In the design of these robots many research findings of human-human interaction and human-computer interaction are adopted but the direct applicability of these theories is limited because a robot is different from both humans and computers. Therefore, new methods have to be developed in HRI in order to build robots that are suitable for inexperienced users. In this paper we present a video study we conducted employing our robot BIRON (BIelefeld RObot companioN) which is designed for use in domestic environments. Subjects watched the system during the interaction with a human and rated two different robot behaviours (extrovert and introvert). The behaviours differed regarding verbal output and person following of the robot. Aiming to improve human-robot interaction, participants' ratings of the behaviours were evaluated and compared.
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| 23. |
- Moss, Brian D., et al.
(författare)
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Climate change and the future of freshwater biodiversity in Europe : a primer for policy-makers
- 2009
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Ingår i: Freshwater Reviews. - : Freshwater Biological Association. - 1755-084X. ; 2:2, s. 103-130
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Tidskriftsartikel (refereegranskat)abstract
- Earth's climate is changing, and by the end of the 21st century in Europe, average temperatures are likely to have risen by at least 2 °C, and more likely 4 °C with associated effects on patterns of precipitation and the frequency of extreme weather events. Attention among policy-makers is divided about how to minimise the change, how to mitigate its effects, how to maintain the natural resources on which societies depend and how to adapt human societies to the changes. Natural systems are still seen, through a long tradition of conservation management that is largely species-based, as amenable to adaptive management, and biodiversity, mostly perceived as the richness of plant and vertebrate communities, often forms a focus for planning. We argue that prediction of particular species changes will be possible only in a minority of cases but that prediction of trends in general structure and operation of four generic freshwater ecosystems (erosive rivers, depositional floodplain rivers, shallow lakes and deep lakes) in three broad zones of Europe (Mediterranean, Central and Arctic-Boreal) is practicable. Maintenance and rehabilitation of ecological structures and operations will inevitably and incidentally embrace restoration of appropriate levels of species biodiversity. Using expert judgement, based on an extensive literature, we have outlined, primarily for lay policy makers, the pristine features of these systems, their states under current human impacts, how these states are likely to alter with a warming of 2 °C to 4 °C and what might be done to mitigate this. We have avoided technical terms in the interests of communication, and although we have included full referencing as in academic papers, we have eliminated degrees of detail that could confuse broad policy-making
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| 24. |
- Mälarstig, Anders, 1975-
(författare)
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Tissue Factor and CD40 Ligand : Markers for the Interplay of Coagulation and Inflammation in the Acute Coronary Syndrome
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- BACKGROUND: Tissue factor (TF) is a 47 kDa transmembrane glycoprotein known as the main initiator of blood coagulation. CD40 ligand is another membrane molecule, which ligates to cell types associated with atherosclerotic plaques thereby mediating intraplaque inflammation and weakening of the fibrous cap. Acute coronary syndrome (ACS) is a multi-factorial disease in which TF and CD40 ligand have prominent roles. Single nucleotide poly-morphisms (SNPs) in the TF and CD40 ligand genes may influence the development, pro-gression and outcome in ACS. AIM: The aim of this thesis was to investigate the genetic and molecular control of TF expression in healthy individuals and in patients with ACS. More-over, the aim was to investigate whether SNPs in the TF and CD40L genes respectively were associated with risk and outcome in ACS and / or with plasma concentrations of these pro-teins. RESULTS: A real-time PCR method that allowed sensitive and dynamic quantification of TF mRNA was established and used for the identification of a high and low response phe-nomenon of TF mRNA. The TF high and low response correlated with the expression of toll-like receptor 4 (TLR-4) thus linking TF to innate immunity in a novel fashion. Investigation of several SNPs in the TF and CD40L genes led to the identification of the 5466 A>G in the TF gene and the -3459 A>G SNP in the CD40L gene. The 5466 G allele was associated with cardiovascular death in patients with ACS and increased TF procoagulant activity in human monocytes, which explained the clinical association. The -3459 G allele regulated the produc-tion of soluble CD40L but was not related with patient outcome. Soluble CD40L levels above median were associated with the risk of MI in patients with ACS. A prolonged treatment with dalteparin was more efficient in patients presenting with high levels of sCD40L, which further supports sCD40L as a marker of a prothrombotic state. CONCLUSIONS: The results of this thesis adds to our current knowledge of factors influencing TF expression and activity by demonstrating the effects of TF gene variants, cell signalling molecules, CD40 ligand protein and gene variation. All of these effects have the potential to modify the risk of development, progression and outcome in the acute coronary syndrome and exemplify the interplay between coagulation and inflammation, in which both TF and CD40 ligand are active.
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| 25. |
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