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71.
The entertainment industry, primarily the video games industry, continues to dictate the development and performance requirements
of graphics hardware and computer graphics algorithms. However, despite the enormous progress in the last few years, it is
still not possible to achieve some of industry’s demands, in particular high-fidelity rendering of complex scenes in real-time,
on a single desktop machine. A realisation that sound/music and other senses are important to entertainment led to an investigation
of alternative methods, such as cross-modal interaction in order to try and achieve the goal of “realism in real-time”. In
this paper we investigate the cross-modal interaction between vision and audition for reducing the amount of computation required
to compute visuals by introducing movement related sound effects. Additionally, we look at the effect of camera movement speed
on temporal visual perception. Our results indicate that slow animations are perceived as smoother than fast animations. Furthermore,
introducing the sound effect of footsteps to walking animations further increased the animation smoothness perception. This
has the consequence that for certain conditions, the number of frames that need to be rendered each second can be reduced,
saving valuable computation time, without the viewer being aware of this reduction. The results presented are another step
towards the full understanding of the auditory-visual cross-modal interaction and its importance for helping achieve “realism
int real-time”. 相似文献
72.
Interface structure of diffusion bonded duplex stainless steel and medium carbon steel couple 总被引:2,自引:0,他引:2
Diffusion bonding of duplex stainless steel to medium carbon steel was carried out with different temperatures for sound bonds. In the bonding process, relatively intermediate temperatures such as 750, 800, 850 and 900 °C were used with a bonding time of 30 min. In this study, microstructural changes and mechanical properties in the interface region of duplex stainless steel and medium carbon steel couples were determined. The results showed that, in interface region, Cr23C6 was formed on the stainless steel side, while ferrite formation was observed on the carbon steel side as a result of mutual diffusion of C and Cr. 相似文献
73.
Gawronski Bertram; LeBel Etienne P.; Peters Kurt R.; Banse Rainer 《Canadian Metallurgical Quarterly》2009,135(3):369
J. De Houwer, S. Teige-Mocigemba, A. Spruyt, and A. Moors’s (see record 2009-05290-001) normative analysis of implicit measures provides an excellent clarification of several conceptual ambiguities surrounding the validation and use of implicit measures. The current comment discusses an important, yet unacknowledged, implication of J. De Houwer et al.’s analysis, namely, that investigations addressing the proposed implicitness criterion (i.e., does the relevant psychological attribute influence measurement outcomes in an automatic fashion?) will be susceptible to fundamental misinterpretations if they are conducted independently of the proposed what criterion (i.e., is the measurement outcome causally produced by the psychological attribute the measurement procedure was designed to assess?). As a solution, it is proposed that experimental validation studies should be combined with a correlational approach in order to determine whether a given manipulation influenced measurement scores via variations in the relevant psychological attribute or via secondary sources of systematic variance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Robert L. Wolff Olivier Lavialle Frédérique Pédrono Elodie Pasquier Laurent G. Deluc Anne M. Marpeau Kurt Aitzetmüller 《Lipids》2001,36(5):439-451
Following our previous review on Pinus spp. seed fatty acid (FA) compositions, we recapitulate here the seed FA compositions of Larix (larch), Picea (spruce), and Pseudotsuga (Douglas fir) spp. Numerous seed FA compositions not described earlier are included. Approximately 40% of all Picea taxa and one-third of Larix taxa have been analyzed so far for their seed FA compositions. Qualitatively, the seed FA compositions in the three genera
studied here are the same as in Pinus spp., including in particular the same Δ5-olefinic acids. However, they display a considerably lower variability in Larix and Picea spp. than in Pinus spp. An assessment of geographical variations in the seed FA composition of P. abies was made, and intraspecific dissimilarities in this species were found to be of considerably smaller amplitude than interspecific
dissimilarities among other Picea species. This observation supports the use of seed FA compositions as chemotaxonomic markers, as they practically do not
depend on edaphic or climatic conditions. This also shows that Picea spp. are coherently united as a group by their seed FA compositions. This also holds for Larix spp. Despite a close resemblance between Picea and Larix spp. seed FA compositions, principal component analysis indicates that the minor differences in seed FA compositions between
the two genera are sufficient to allow a clear-cut individualization of the two genera. In both cases, the main FA is linoleic
acid (slightly less than one-half of total FA), followed by pinolenic (5,9,12-18:3) and oleic acids. A maximum of 34% of total
Δ5-olefinic acids is reached in L. sibirica seeds, which appears to be the highest value found in Pinaceae seed FA. This apparent limit is discussed in terms of regio-
and stereospecific distribution of Δ5-olefinic acids in seed triacylglycerols. Regarding the single species of Pseudotsuga analyzed so far (P. menziesii), its seed FA composition is quite distinct from that of the other two genera, and in particular, it contains 1.2% of 14-methylhexadecanoic
(anteiso-17:0) acid. In the three genera studied here, as well as in most Pinus spp., the C18Δ5-olefinic acids (5,9-18:2 and 5,9,12-18:3 acids) are present in considerably higher amounts than the C20Δ5-olefinic acids (5,11-20:2 and 5,11,14-20:3 acids). 相似文献
75.
Efficient real-time trajectory tracking 总被引:1,自引:0,他引:1
Ralph Lange Frank Dürr Kurt Rothermel 《The VLDB Journal The International Journal on Very Large Data Bases》2011,20(5):671-694
Moving objects databases (MOD) manage trajectory information of vehicles, animals, and other mobile objects. A crucial problem
is how to efficiently track an object’s trajectory in real-time, in particular if the trajectory data is sensed at the mobile
object and thus has to be communicated over a wireless network. We propose a family of tracking protocols that allow trading
the communication cost and the amount of trajectory data stored at a MOD off against the spatial accuracy. With each of these
protocols, the MOD manages a simplified trajectory that does not deviate by more than a certain accuracy bound from the actual
movement. Moreover, the different protocols enable several trade-offs between computational costs, communication cost, and
the reduction in the trajectory data: Connection-Preserving Dead Reckoning minimizes the communication cost using dead reckoning, a technique originally designed for tracking an object’s current position.
Generic Remote Trajectory Simplification (GRTS) further separates between tracking of the current position and simplification of the past trajectory and can be realized
with different line simplification algorithms. For both protocols, we discuss how to bound the space consumption and computing
time at the moving object and thereby present an effective compression technique to optimize the reduction performance of
real-time line simplification in general. Our evaluations with hundreds of real GPS traces show that a realization of GRTS
with a simple simplification heuristic reaches 85–90% of the best possible reduction rate, given by retrospective offline
simplification. A realization with the optimal line simplification algorithm by Imai and Iri even reaches more than 97% of
the best possible reduction rate. 相似文献
76.
Improving classroom learning by collaboratively observing human tutoring videos while problem solving. 总被引:1,自引:0,他引:1
Craig Scotty D.; Chi Michelene T. H.; VanLehn Kurt 《Canadian Metallurgical Quarterly》2009,101(4):779
Collaboratively observing tutoring is a promising method for observational learning (also referred to as vicarious learning). This method was tested in the Pittsburgh Science of Learning Center’s Physics LearnLab, where students were introduced to physics topics by observing videos while problem solving in Andes, a physics tutoring system. Students were randomly assigned to three groups: (a) pairs collaboratively observing videos of an expert human tutoring session, (b) pairs observing videos of expert problem solving, or (c) individuals observing expert problem solving. Immediate learning measures did not display group differences; however, long-term retention and transfer measures showed consistent differences favoring collaboratively observing tutoring. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Daniel E. Canfield Jr Darren J. Pecora Kurt W. Larson Jesse Stephens Mark V. Hoyer 《Lakes & Reservoirs: Research and Management》2013,18(3):239-245
Stocking of largemouth bass is an important management tool for fish management. The stocking of hatchery‐produced fingerling or advanced‐fingerling bass to supplement bass year‐classes, however, has exhibited varying success. Utilizing a different approach, a multiyear stocking programme using wild adult largemouth bass was initiated at the Harris Chain of Lakes (3800 ha Lake Griffin; 1811 ha Lake Dora) in central Florida. Wild adult bass (24 781 fish), ranging in size from 200 mm total length (TL) to over 600 mm TL, were stocked in Lake Griffin (13 932 fish) and Lake Dora (10 849 fish). One month after stocking, the number of stocked bass caught in electrofishing catches in Lake Griffin and Lake Dora was ~10% and 22%, respectively. Estimates of mortality were similar to the native largemouth bass, although the movement of stocked fish into other connecting water bodies was extensive. For the Lake Griffin/Lake Dora stocking programme, bass were transferred at a cost of $10.09–19.89 per fish, depending on how the costs of the project are calculated ($250 000 for just the capture and transport of the fish vs. $492 775 for the total project). Considering only capture and transport costs, conservative benefit/cost ratio estimates would be $1.77/$1.00 spent for replacement and $1.85/$1.00 spent recreational costs, although the benefit/cost ratios could exceed $10/$1. Based on the present study, stocking wild adult largemouth bass is a cost‐effective tool for managing largemouth bass. 相似文献
78.
Kurt Kornbluth Zach McCaffrey Paul A. Erickson 《International Journal of Hydrogen Energy》2009,34(22):9248-9257
A 0.745 L 2-cylinder spark-ignition engine was operated with compressed natural gas and with simulated landfill gas (60% CH4 and 40% CO2 by volume) containing hydrogen concentrations of 0, 30%, 40%, and 50% (by volume of the CH4 in the fuel) at constant rpm. This empirical data was compared with predictions from three existing semi-empirical engine models, using a first-law-based finite heat release model to correlate measured in-cylinder pressure data and burn rate for each fuel mixture. Of the three models only a two zone model incorporating thermal and prompt NOx came within 25% of predicting the measured NOx emissions. 相似文献
79.
Towards cognitive evaluation of computer-drawn sketches 总被引:1,自引:0,他引:1
This paper seeks to raise visual comparisons beyond subjective opinions into evidence-based visual reasoning. It provides
an informal deductive analysis of the marks in sketches derived with two competing line-filtering algorithms. This prompted
the novel speculation that the visual system might be placing some types of anomalies in the foreground of mental 3D space,
where they can be ignored. A brief survey is provided to encourage informed debate. Although the proposed cognitive computation
was not automated, it justified the rejection of the Douglas–Peucker algorithm in favour of Visvalingam's algorithm in subsequent
research within the Cartographic Information Systems Research Group (CISRG). 相似文献
80.
Stuart Crozier Ph.D. Stephen Dodd Kurt Luescher James Field David M. Doddrell 《Magma (New York, N.Y.)》1995,3(1):49-55
By extending the formalism previously developed for the design of unshielded, biplanar gradient coils, shielded biplanarB
0 coils optimized for homogeneity and either minimum energy or minimum power may be designed. We present results from an integrated
approach to shielded biplanar coil design, the results of which are also applicable to gradient coils, enabling the design
of shielded coils with a concomitant decrease in total inductance of the coil. Length constraints are also included in the
integrated minimization procedure. Results from a preliminary design indicate that high-homogeneity, low-impedance, well-shielded
coils result from this design approach. 相似文献