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241.
Toni Järvenpää Marja Salmimaa Tapani Levola 《Journal of the Society for Information Display》2011,19(2):230-237
Abstract— Virtual‐image (near‐to‐eye) and two‐view autostereoscopic (3‐D) displays share similar optical properties in the comfortable user position for viewing. In this paper, the definitions and criteria of qualified viewing space (QVS) and qualified stereoscopic viewing space (QSVS) are discussed. Due to the complex nature of these viewing spaces, the related presumptions and the required optical characteristics and their measurements are specified. The effects of different display and observer parameters, such as interpupillary distance, to the resulting viewing spaces are discussed. Finally, real measurement data of two autostereoscopic display devices are presented. 相似文献
242.
Adam Kłodowski Timo Rantalainen Aki Mikkola Ari Heinonen Harri Sievänen 《Multibody System Dynamics》2011,25(4):395-409
A method for bone strain estimation is examined in this article. The flexibility of a single bone in an otherwise rigid human
skeleton model has been studied previously by various authors. However, in the previous studies, the effect of the flexibility
of multiple bones on the musculoskeletal model behavior was ignored. This study describes a simulation method that can be
used to estimate the bone strains at both tibias and femurs of a 65-year-old Caucasian male subject. The verification of the
method is performed by the comparison of the results with other studies available in literature. The results of the study
show good correlation with the results of previous empirical studies. A damping effect of the flexible bones on the model
is also studied in this paper. 相似文献
243.
Jukka Mäkelä Markus Luoto Tiia Sutinen Kostas Pentikousis 《Multimedia Tools and Applications》2011,55(2):289-306
Multimedia delivery in mobile multiaccess network environments has emerged as a key area within the future Internet research
domain. When network heterogeneity is coupled with the proliferation of multiaccess capabilities in mobile handheld devices,
one can expect many new avenues for developing novel services and applications. New mechanisms for audio/video delivery over
multiaccess networks will define the next generation of major distribution technologies, but will require significantly more
information to operate according to their best potential. In this paper we present and evaluate a distributed information
service, which can enhance media delivery over such multiaccess networks. We describe the proposed information service, which
is built upon the new distributed control and management framework (DCMF) and the mobility management triggering functionality
(TRG). We use a testbed which includes 3G/HSPA, WLAN and WiMAX network accesses to evaluate our proposed architecture and
present results that demonstrate its value in enhancing video delivery and minimizing service disruption in an involved scenario. 相似文献
244.
The purpose of this study was to investigate whether training in a microworld had an effect on the decision-making process
in a command-and-control training facility. Fourteen battalion commanders participated in the study. Prior to performing the
main task in the command-and-control facility, seven participants (the experimental group) received training in the microworld.
Seven participants (the control group) received no training before the main task. The results show that the experimental group
performed better than the control group, measured by self-ratings and by fulfilling the instructors’ criteria. The experimental
group displayed a different decision-making behaviour in the main task than the control group did. The results indicate that
the experimental group used some behaviour characteristics they learnt during training, namely “working systematically” and
“causal relationship”. Thus, the study shows that favourable behaviour was learnt in the microworld, and that behaviour was
subsequently used in the command-and-control training facility. 相似文献
245.
This special issue collects current advances in the ongoing attempt to obtain synergies from the combination of Tests and
Proofs. 相似文献
246.
Salience detection is a principle mechanism to facilitate visual attention. A good visualization guides the observer's attention to the relevant aspects of the representation. Hence, the distribution of salience over a visualization image is an essential measure of the quality of the visualization. We describe a method for computing such a metric for a visualization image in the context of a given dataset. We show how this technique can be used to analyze a visualization's salience, improve an existing visualization, and choose the best representation from a set of alternatives. The usefulness of this proposed metric is illustrated using examples from information visualization, volume visualization and flow visualization. 相似文献
247.
Sound is an integral part of most movies and videos. In many situations, viewers of a video are unable to hear the sound track, for example, when watching it in a fast forward mode, viewing it by hearing‐impaired viewers or when the plot is given as a storyboard. In this paper, we present an automated visualization solution to such problems. The system first detects the common components (such as music, speech, rain, explosions, and so on) from a sound track, then maps them to a collection of programmable visual metaphors, and generates a composite visualization. This form of sound visualization, which is referred to as SoundRiver, can be also used to augment various forms of video abstraction and annotated key frames and to enhance graphical user interfaces for video handling software. The SoundRiver conveys more semantic information to the viewer than traditional graphical representations of sound illustration, such as phonoautographs, spectrograms or artistic audiovisual animations. 相似文献
248.
Lei Xie Monika Leester-Schädel Gerhard Ziegmann Stephanus Büttgenbach 《Microsystem Technologies》2010,16(6):1009-1013
Micro injection molded polymeric parts coated with functional thin films/layers show off the promising applications in microsystems
area. But the unfavorable and unavoidable defect of weld line in micro injection molding part leads to detrimental mechanical
and surface properties. The possibility of the functional thin film for enhancing micro injection molded weld lines was investigated.
Two typical coating materials (aluminum and titanium) with various film thicknesses (400, 600, 800 nm) were deposited on one
side of the micro injection molded weld line tensile sample via physical vapor deposition (PVD) method. The coated micro weld
line samples were characterized by tensile tests. The results show that PVD films of aluminum and titanium can reinforce the
strength and stiffness of micro injection molded weld line, even at thin thickness levels. But when the film thickness is
increasing, the weaker adhesion between metallic films and polymers decreased the PVD films’ enhancing performance for micro
weld line mechanical properties due to the degradation of polymers related to longer time exposure under high temperature. 相似文献
249.
In this paper, we examine whether or not information theory can be one of the theoretic frameworks for visualization. We formulate concepts and measurements for qualifying visual information. We illustrate these concepts with examples that manifest the intrinsic and implicit use of information theory in many existing visualization techniques. We outline the broad correlation between visualization and the major applications of information theory, while pointing out the difference in emphasis and some technical gaps. Our study provides compelling evidence that information theory can explain a significant number of phenomena or events in visualization, while no example has been found which is fundamentally in conflict with information theory. We also notice that the emphasis of some traditional applications of information theory, such as data compression or data communication, may not always suit visualization, as the former typically focuses on the efficient throughput of a communication channel, whilst the latter focuses on the effectiveness in aiding the perceptual and cognitive process for data understanding and knowledge discovery. These findings suggest that further theoretic developments are necessary for adopting and adapting information theory for visualization. 相似文献
250.
We investigate quantitative extensions of modal logic and the modal μ-calculus, and study the question whether the tight connection between logic and games can be lifted from the qualitative
logics to their quantitative counterparts. It turns out that, if the quantitative μ-calculus is defined in an appropriate way respecting the duality properties between the logical operators, then its model
checking problem can indeed be characterised by a quantitative variant of parity games. However, these quantitative games
have quite different properties than their classical counterparts, in particular they are, in general, not positionally determined.
The correspondence between the logic and the games goes both ways: the value of a formula on a quantitative transition system
coincides with the value of the associated quantitative game, and conversely, the values of quantitative parity games are
definable in the quantitative μ-calculus. 相似文献