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Suche nach „[2013]“ hat 285 Publikationen gefunden
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    DigitalBauingenieurwesen und Umwelttechnik

    Vortrag

    Gerd Maurer

    Building Information Modeling (BIM) im Industriebau

    Talk

    2013

    DigitalBauingenieurwesen und Umwelttechnik

    Zeitschriftenartikel

    Gerd Maurer

    Modell und Wirklichkeit. Expertenmeinung: Wohin steuert BIM?

    AUTOCAD & Inventor Magazin (Architektur & Bauwesen), no. 6, pp. 38-39

    2013

    DigitalAngewandte Informatik

    Zeitschriftenartikel

    K. Brunnström, I. Ananth, C. Hedberg, K. Wang, B. Andrén, Marcus Barkowsky

    36.4: Comparison between Different Rating Scales for 3D TV

    SID Symposium Digest of Technical Papers, vol. 44, no. 1, pp. 509-512

    2013

    DOI: 10.1002/j.2168-0159.2013.tb06256.x

    Abstract anzeigen

    Stereoscopic 3D viewing experience has been studied quite intensively recently, but still the subjective test methods have not yet been settled. It has become clear that the 3D viewing experience cannot easily be described by just one scale. This paper describes a study where three different rating scales (Quality, Discomfort and Presence) are compared in a subjective test, combined with two viewing distances. The results shows that in a stereoscopic 3D video quality test targeting mainly coding distortions one scale such as video quality could be sufficient.

    DigitalAngewandte Informatik

    Zeitschriftenartikel

    W. Chen, J. Fournier, Marcus Barkowsky, P. Le Callet

    Methodologies for Assessing 3D QoE: Standards and Explorative Studies

    ZTE Communications, vol. 11, no. 1, pp. 2-10

    2013

    Abstract anzeigen

    Mastering quality of experience (QoE) is key to the widespread adoption of stereoscopic 3DTV (S-3DTV). However, assessing QoE of S-3DTV is not straightforward. Methods for determining observer experience need to be clearly defined and sufficiently robust. In this paper, we present state-of-the-art subjective QoE assessment for S-3DTV. We present conventional stan⁃ dardized ITU recommendations for evaluating picture quality and discuss new ITU activities in the area of S-3DTV assess⁃ ment. We also present and discuss explorative studies from the literature. We then introduce ways of using conventional quality assessment for S-3DTV QoE assessment. In discussing our pro⁃ posal, we mainly focus on QoE indicators and common features of subjective assessment. Multidimensional QoE indicators need to be used in S-3DTV to highlight advantages and reveal problems. In the second part of our proposal, we discuss the re⁃ quirements for adapting ITU-R BT.500, a conventional subjec⁃ tive QoE assessment method, ITU-R BT.500, for assessing QoE of S-3DTV are presented.

    DigitalAngewandte Informatik

    Zeitschriftenartikel

    M. Pinson, Marcus Barkowsky, P. Le Callet

    Selecting scenes for 2D and 3D subjective video quality tests

    EURASIP Journal on Image and Video Processing, no. 1

    2013

    Abstract anzeigen

    This paper presents recommended techniques for choosing video sequences for subjective experiments. Subjective video quality assessment is a well-understood field, yet scene selection is often driven by convenience or content availability. Three-dimensional testing is a newer field that requires new considerations for scene selection. The impact of experiment design on best practices for scene selection will also be considered. A semi-automatic selection process for content sets for subjective experiments will be proposed.

    DigitalAngewandte Informatik

    Zeitschriftenartikel

    M. Urvoy, Marcus Barkowsky, P. Le Callet

    How visual fatigue and discomfort impact 3D-TV quality of experience: a comprehensive review of technological, psychophysical, and psychological factors

    Annales des Télécommunications, vol. 68, no. 11-12, pp. 641-655

    2013

    DOI: 10.1007/s12243-013-0394-3

    Abstract anzeigen

    The quality of experience (QoE) of 3D contents is usually considered to be the combination of the perceived visual quality, the perceived depth quality, and lastly the visual fatigue and comfort. When either fatigue or discomfort are induced, studies tend to show that observers prefer to experience a 2D version of the contents. For this reason, providing a comfortable experience is a prerequisite for observers to actually consider the depth effect as a visualization improvement. In this paper, we propose a comprehensive review on visual fatigue and discomfort induced by the visualization of 3D stereoscopic contents, in the light of physiological and psychological processes enabling depth perception. First, we review the multitude of manifestations of visual fatigue and discomfort (near triad disorders, symptoms for discomfort), as well as means for detection and evaluation. We then discuss how, in 3D displays, ocular and cognitive conflicts with real world experience may cause fatigue and discomfort; these includes the accommodation-vergence conflict, the inadequacy between presented stimuli and observers depth of focus, and the cognitive integration of conflicting depth cues. We also discuss some limits for stereopsis that constrain our ability to perceive depth, and in particular the perception of planar and in-depth motion, the limited fusion range, and various stereopsis disorders. Finally, this paper discusses how the different aspects of fatigue and discomfort apply to 3D technologies and contents. We notably highlight the need for respecting a comfort zone and avoiding camera and rendering artifacts. We also discuss the influence of visual attention, exposure duration, and training. Conclusions provide guidance for best practices and future research.

    DigitalAngewandte Informatik

    Zeitschriftenartikel

    J. Li, Marcus Barkowsky, P. Le Callet

    Recent Advances in Standardization on 3D Quality of Experience

    IEEE COMSOCMMTC E-Letter, vol. 8, no. 3

    2013

    Abstract anzeigen

    For the last decades, video quality assessment has mostly tackled 2D video sequences. Technological advances were mostly tackling coding and transmission schemes while the display technology, especially in lab viewing environments, could be considered as transparent. Subjective assessment methodologies needed to be selected mostly with respect to the severity of the degradations. Typical examples are Absolute Category Rating with Hidden Reference (ACR-HR) from ITU-T P.910 for strong degradations experienced in networked multimedia scenarios, and Paired Comparison (PC) or Double Stimulus Continuous Quality Scale (DSCQS) from ITU-R BT.500 for near lossless scenarios such as satellite transmissions.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    K. Wang, K. Brunnström, Marcus Barkowsky, M. Urvoy, M. Sjöström, P. Le Callet, S. Tourancheau, B. Andrén

    Stereoscopic 3D video coding quality evaluation with 2D objective metrics

    Proceedings of SPIE Vol. 8648: Stereoscopic Displays and Applications XXIV

    2013

    Abstract anzeigen

    The 3D video quality is of highest importance for the adoption of a new technology from a user’s point of view. In this paper we evaluated the impact of coding artefacts on stereoscopic 3D video quality by making use of several existing full reference 2D objective metrics. We analyzed the performance of objective metrics by comparing to the results of subjective experiment. The results show that pixel based Visual Information Fidelity metrics fits subjective data the best. The 2D stereoscopic video quality seems to have dominant impact on the coding artefacts impaired stereoscopic videos.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    J. Li, Marcus Barkowsky, P. Le Callet

    Boosting Paired Comparison methodology in measuring visual discomfort of 3DTV: Performances of three different designs

    Proceedings of SPIE Vol. 8648: Stereoscopic Displays and Applications XXIV

    2013

    Abstract anzeigen

    The pair comparison method is often recommended in subjective experiments because of the reliability of the obtained results. However, a drawback of this method is that the number of comparisons increases exponentially with the number of stimuli, which limits its usability for a large number of stimuli. Several design methods that aim to reduce the number of comparisons were proposed in the literature. However, their performances in the context of 3DTV should be evaluated carefully due to the fact that the results obtained from a paired comparison experiment in 3DTV may be influenced by two important factors. One is the observation error from observer's attentiveness, in particular inverting the vote. The second factor concerns the dependence on the context in which the evaluation takes place. In this study, three design methods, namely Full Paired Comparison method (FPC), Square Design method (SD) and the Adaptive Square Design method (ASD) were evaluated by subjective visual discomfort experiment in 3DTV. The results from the FPC method were considered as the ground truth. Comparing with the ground truth, the ASD method provided the most accurate results with a given number of trials. It also showed the highest robustness against observation errors and interdependence of comparisons. Due to the efficiency of the ASD method, paired comparison experiments become feasible with a reasonably large number of stimuli for measuring 3DTV visual discomfort.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    Marcus Barkowsky, J. Li, T. Han, S. Youn, J. Ok, C. Lee, I. Vijai Ananth, K. Wang, K. Brunnström, P. Le Callet

    Towards standardized 3DTV QoE assessment: Cross-lab study on display technology and viewing environment parameters

    Proceedings of SPIE Vol. 8648: Stereoscopic Displays and Applications XXIV;

    2013

    Abstract anzeigen

    Subjective assessment of Quality of Experience in stereoscopic 3D requires new guidelines for the environmental setup as existing standards such as ITU-R BT.500 may no longer be appropriate. A first step is to perform cross-lab experiments in different viewing conditions on the same video sequences. Three international labs performed Absolute Category Rating studies on a freely available video database containing degradations that are mainly related to video quality degradations. Different conditions have been used in the labs: Passive polarized displays, active shutter displays, differences in viewing distance, the number of parallel viewers, and the voting device. Implicit variations were introduced due to the three different languages in Sweden, South Korea, and France. Although the obtained Mean Opinion Scores are comparable, slight differences occur in function of the video degradations and the viewing distance. An analysis on the statistical differences obtained between the MOS of the video sequences revealed that obtaining an equivalent number of differences may require more observers in some viewing conditions. It was also seen that the alignment of the meaning of the attributes used in Absolute Category Rating in different languages may be beneficial. Statistical analysis was performed showing influence of the viewing distance on votes and MOS results.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    J. Li, Marcus Barkowsky, P. Le Callet

    Visual Discomfort is not always proportonal to Eye Blinking Rate: Exploring Some Effects of Planar and In-Depth Motion on 3DTV QoE

    International Workshop on Video Processing and Quality Metrics for Consumer Electronics VPQM 2013 (Jan 2013; Scottsdale, AZ, USA)

    2013

    Abstract anzeigen

    Visual discomfort is an important factor in determiningQoE in 3DTV. It can be measured by physiological signals. Inthis study, the relationship between 3D video characteristics(e.g., motion type, disparity, velocity, etc), visual discom-fort and eye blinking rate were studied. Three motion typeswere considered, which were static scenes, planar motionand in-depth motion. 44 stimuli with different motion types,disparity levels and velocity levels were studied. The eyeblinking signals of 28 observers were obtained by an electro-physiological measurement device. The experimental resultsshowed that stimulus velocity affected eye blinks significantlyand differently for planar motion stimuli and in-depth motionstimuli. The objective eye blinking model for 3D stimuliwas developed in function of the 3D video characteristics.Furthermore, the results showed that eye blinking rate wasproportional to the visual discomfort of the static 3D stimulibut inversely proportional to the visual discomfort of planarmotion stimuli.

    DigitalBauingenieurwesen und Umwelttechnik

    Zeitschriftenartikel

    Gerd Maurer

    Modell und Wirklichkeit. Expertenmeinung: Wohin steuert BIM?

    Statement-Artikel

    AUTOCAD & Inventor Magazin (Architektur & Bauwesen), no. 6, pp. 38-39

    2013

    DigitalBauingenieurwesen und Umwelttechnik

    Zeitschriftenartikel

    Gerd Maurer

    Building Information Modeling (BIM) aus der Praxis

    Statement-Artikel

    Architektur Aktuell, Wien, no. 404

    2013

    Angewandte Wirtschaftswissenschaften

    Buch (Monographie)

    S. Arent, Wolfgang Nagl, J. Ragnitz

    Bildungsland Sachsen - Eine Zukunftsinvestition für Deutschland

    ifo Dresden Studien, München, vol. 68

    2013

    ISBN: 978-3-88512-534-1

    Abstract anzeigen

    Gutachten im Auftrag der Sächsischen Staatskanzlei. Bildung ist eine der zentralen föderalen Aufgaben in Deutschland. So können die Bundesländer die Bildungspolitik weitgehend alleine gestalten, müssen allerdings auch die Ausgaben dafür tragen. Die Bildungsausgaben stellen einen der größten Posten den Länderhaushalten dar. Ökonomisch interessant und politisch brisant werden die föderalen Bildungsausgaben vor dem Hintergrund der innerdeutschen Wanderung. Für den Freistaat Sachsen werden in diesem Projekt die mit den Wanderungsströmen fließenden Bildungsinvestitionen von und nach jedem Bundesland bestimmt. Um die Bildungsinvestitionssalden zu bestimmen, erfolgt in einem ersten Schritt eine altersspezifische Analyse der einzelnen Wanderungsströme mit jedem Bundesland. Es zeigt sich, dass aus den anderen ostdeutschen Flächenländern eine Nettozuwanderung nach Sachsen stattfindet, während mehr Menschen aus Sachsen in die westdeutschen Länder abwandern, als von dort zuwandern. Die meisten Personen wandern dabei in die großen und wirtschaftlich starken südlichen Bundesländer ab. Insgesamt ist der Wanderungssaldo 2008 für Sachsen deutlich negativ. Wanderung findet hauptsächlich zwischen dem 20. und dem 35. Lebensjahr statt, sodass netto aus Sachsen tendenziell junge und gut ausgebildete Personen abwandern. Um den tatsächlichen Transfer von Bildungsinvestitionen zu quantifizieren, werden in einem zweiten Schritt die Bildungskosten in jedem Bundesland bestimmt. Es werden dann spezifische Bildungskosten für jedes Altersjahr bzw. Qualifikationsniveau bestimmt. In einem letzten Schritt werden diese alters- und qualifikationsspezifischen Bildungskosten auf die Wanderungsströme übertragen. Analog zu den Wanderungsströmen fließen Sachsen netto Bildungsinvestitionen aus den anderen ostdeutschen Bundesländern zu, aber Bildungsinvestitionen nach den westdeutschen Bundesländern ab. Insgesamt verliert Sachsen mehr Bildungsinvestitionen als es gewinnt.

    Angewandte Wirtschaftswissenschaften

    Zeitschriftenartikel

    S. Arent, Wolfgang Nagl, J. Ragnitz

    Öffentliche Ausgaben der Länder für Bildung

    ifo Dresden berichtet, vol. 20, no. 2, pp. 10-18

    2013

    Abstract anzeigen

    Bildung ist eine der zentralen Aufgaben der Bundesländer. In dem vorliegenden Beitrag werden die Ausbildungskosten in den 16 Bundesländern verglichen. Dazu werden mit Hilfe von amtlichen Daten die häufigsten Bildungskarrieren konstruiert. Ein Schwerpunkt der Untersuchung liegt dabei auf der vergleichsweise teuren universitären Ausbildung. Im Vergleich zu den anderen Bundesländern zeigt sich, dass die Bildungsausgaben in Sachsen relativ hoch sind. Bis zum Abitur investiert der Freistaat Sachen über 100.000€ in die Ausbildung eines Jugendlichen. Für einen durchschnittlichen Universitätsabsolventen werden über 155.000 € ausgegeben.

    Angewandte Wirtschaftswissenschaften

    Zeitschriftenartikel

    Wolfgang Nagl, L. Vandrei

    Der Beitrag zur Gesetzlichen Rentenversicherung im demographischen Wandel – Die Babyboomer gehen in Rente

    ifo Dresden berichtet, vol. 20, no. 4, pp. 30-33

    2013

    Abstract anzeigen

    Immer weniger Beitragszahler müssen zukünftig für immer mehr Rentner aufkommen. Gerade mit dem Eintritt der Babyboomer-Generation in die Rente steigt der Rentenquotient deutlich an. In einer Simulationsrechnung wird die voraussichtliche Entwicklung des Beitragssatzes zur Gesetzlichen Rentenversicherung bis ins Jahr 2040 aufgezeigt. Die Ergebnisse werden dabei mit den beiden Studien von HOLTHAUSEN et al. (2012) und WERDING (2013) verglichen. Alle drei Modelle prognostizieren einen signifikanten Anstieg des Beitragssatzes auf einen Wert zwischen 23,7 % und 24,8 %. Mittelfristig lässt sich der Übergang der Babyboom-Generation durch eine verstärkte Erwerbsbeteiligung der Frauen und der älteren Kohorten etwas abfedern, langfristig bedarf es aber einer längeren Lebensarbeitszeit, um den Anstieg des Beitragssatzes zu begrenzen.

    Angewandte Wirtschaftswissenschaften

    Zeitschriftenartikel

    Wolfgang Nagl, S. Arent

    Unemployment Compensation and Wages: Evidence from the German Hartz Reforms

    Jahrbücher für Nationalökonomie und Statistik, vol. 233, no. 4, pp. 450-466

    2013

    DOI: 10.1515/jbnst-2014-0505

    Angewandte Wirtschaftswissenschaften

    Zeitschriftenartikel

    Wolfgang Nagl, L. Vandrei

    Mütterrente: Aus Steuermitteln finanzieren

    Wirtschaftsdienst - Zeitschrift für Wirtschaftspolitik, vol. 93, no. 11

    2013

    DigitalAngewandte WirtschaftswissenschaftenTC Grafenau

    Zeitschriftenartikel

    Michael Scholz, V. Dorner

    The Recipe for the Perfect Review?

    Business & Information Systems Engineering, vol. 5, no. 3, pp. 141-151

    2013

    DOI: 10.1007/s12599-013-0259-3

    Abstract anzeigen

    Online product reviews, originally intended to reduce consumers’ pre-purchase search and evaluation costs, have become so numerous that they are now themselves a source for information overload. To help consumers find high-quality reviews faster, review rankings based on consumers’ evaluations of their helpfulness were introduced. But many reviews are never evaluated and never ranked. Moreover, current helpfulness-based systems provide little or no advice to reviewers on how to write more helpful reviews. Average review quality and consumer search costs could be much improved if these issues were solved. This requires identifying the determinants of review helpfulness, which we carry out based on an adaption of Wang and Strong’s well-known data quality framework. Our empirical analysis shows that review helpfulness is influenced not only by single-review features but also by contextual factors expressing review value relative to all available reviews. Reviews for experiential goods differ systematically from reviews for utilitarian goods. Our findings, based on 27,104 reviews from Amazon.com across six product categories, form the basis for estimating preliminary helpfulness scores for unrated reviews and for developing interactive, personalized review writing support tools. We analyze determinants of review helpfulness in online retailing based on Wang and Strong’s (1996) data quality framework. Helpful reviews consist of 9 % of adjectives, display high product feature entropy, and present opinions that differ from previous reviews for the product in question. Other helpfulness determinants depend on whether experiential or utilitarian products are reviewed. Our research points e-shop providers towards two major improvements in their review systems.

    DigitalAngewandte WirtschaftswissenschaftenTC Grafenau

    Zeitschriftenartikel

    J. Pfeiffer, Michael Scholz

    A Low-Effort Recommendation System with High Accuracy

    Business & Information Systems Engineering, vol. 5, no. 6, pp. 397-408

    2013

    DOI: 10.1007/s12599-013-0295-z

    Abstract anzeigen

    In recent studies on recommendation systems, the choice-based conjoint analysis has been suggested as a method for measuring consumer preferences. This approach achieves high recommendation accuracy and does not suffer from the start-up problem because it is also applicable for recommendations for new consumers or of new products. However, this method requires massive consumer input, which causes consumer reluctance. In a simulation study, we demonstrate the high accuracy, but also the high user’s effort for using a utility-based recommendation system using a choice-based conjoint analysis with hierarchical Bayes estimation. In order to reduce the conflict between consumer effort and recommendation accuracy, we develop a novel approach that only shows Pareto-efficient alternatives and ranks them according to the number of dominated attributes. We demonstrate that, in terms of the decision accuracy of the recommended products, the ranked Pareto-front approach performs better than a recommendation system that employs choice-based conjoint analysis. Furthermore, the consumer’s effort is kept low and comparable to that of simple systems that require little consumer input. In a simulation study, we demonstrate that recommendation systems using a choice-based conjoint analysis with hierarchical Bayes estimation require up to three times higher mental effort for the consumer than simple sorting mechanisms. However, consumers benefit from a choice-based conjoint analysis in terms of a significantly higher utility of the selected product. We further introduce the concept of a ranked Pareto-front which allows consumers to select a product with a better utility than they will select when using a choice-based conjoint analysis for the same low costs that using a simple sorting mechanism require.