12,101 research outputs found
Exploring relationships between touch perception and surface physical properties
This paper reports a study of materials for confectionery packaging. The aim was to explore the touch perceptions of textures and identify their relationships with the surfaces' physical properties. Thirty-seven tactile textures were tested including 22 cardboards, nine flexible materials and six laminate boards. Semantic differential questionnaires were administered to assess responses to touching the textures against six word pairs: warm-cold, slippery-sticky, smooth,-rough, hard-soft, bumpy-flat, and wet-dry. Four physical measurements were conducted to characterize the surfaces' roughness, compliance, friction, and the rate of cooling of an artificial finger when touching the surface. Correlation and regression analyses were carried out to identify the relationships between the people's responses and the physical measurements. Results show that touch perception is often associated with more than one physical property, and the strength and form of the combined contribution can be represented by a regression model. © 2009 Chen, Shao, Barnes, Childs, & Henson
Perceptual learning of dot pattern
Dot pattern is a type of pattern defined by specific spatial relationship among some dots. As a compensation for concrete and meaningful visual stimuli, meaningless dot pattern can be used as stimuli in learning tasks. We performed an experiment for exploring the perceptual learning process of dot pattern against random-dot background. Participants were required to learn two types of dot patterns (9-dot and 11-dot). They were assigned to two groups: participants in Group 1 learned 9-dot pattern first and 11-dot pattern later, while those in Group 2 learned 11-dot pattern first and 9-dot pattern later. The results showed that participants could acquire the spatial relationship of dot pattern through perceptual learning in relatively short learning time. In comparison with 9-dot pattern, learning time of 11-dot pattern was slightly longer and its accuracy rate lower, but there was significant positive transfer effect from 11-dot pattern learning to 9-dot learning
An Experimental Research on Search Order Based on Contour (in Chinese)
Contour is an important cue for pattern recognition. Further feature search may have something to do with contour, which is produced by parallel processing. In this research, 3 experiments were undertaken to explore the effects of contour on searching sequence. Experiment 1 aims at confirming the key role of contour in visual search. It’s results show that there exists mental representation of potential targets in visual search. Experiment 2 aims to verify the hypothesis that the new features produced by two figures’ overlapping will accelerate visual search. The results show that although the figures’ overlapping may produce new features, these byproducts may not make search faster. An alternative hypothesis was introduced that contour has effects on searching sequence. On the basis of contour, the search of distinct features follows this order: in the outer band of contour----along contour----in the inner band of contour. Experiment 3 tests this hypothesis further
Community detection in complex networks using flow simulation
Community detection and analysis is an important part of studying the organization of complex systems in real world, and it�s extensively applied on many fields. Recently, many of existing algorithms are not effective or the results are unstable. In this paper, a new method of community testing is proposed by us based on the conception of flow field. In our approach, each node is represented as a field source and has a tendency to forward data to the connected nodes with highest field strength, after some iterations the nodes with same data information form a community. It is evaluated by us for the approach on some synthetic and real-world networks whose community structures are known. It is demonstrated that the approach performs wellin effectiveness and robustness. © 2017 Association for Computing Machinery
Environment, morphology and stellar populations of bulgeless low surface brightness galaxies
Based on the Sloan Digital Sky Survey DR 7, we investigate the environment,
morphology and stellar population of bulgeless low surface brightness (LSB)
galaxies in a volume-limited sample with redshift ranging from 0.024 to 0.04
and . The local density parameter is used to
trace their environments. We find that, for bulgeless galaxies, the surface
brightness does not depend on the environment. The stellar populations are
compared for bulgeless LSB galaxies in different environments and for bulgeless
LSB galaxies with different morphologies. The stellar populations of LSB
galaxies in low density regions are similar to those of LSB galaxies in high
density regions. Irregular LSB galaxies have more young stars and are more
metal-poor than regular LSB galaxies. These results suggest that the evolution
of LSB galaxies may be driven by their dynamics including mergers rather than
by their large scale environment.Comment: 12 pages, 13 figures, Accepted by A&
Note on a new fundamental length scale instead of the Newtonian constant
The newly proposed entropic gravity suggests gravity as an emergent force
rather than a fundamental one. In this approach, the Newtonian constant
does not play a fundamental role any more, and a new fundamental constant is
required to replace its position. This request also arises from some
philosophical considerations to contemplate the physical foundations for the
unification of theories. We here consider the suggestion to derive from
more fundamental quantities in the presence of a new fundamental length scale
, which is suspected to originate from the structure of quantum space-time,
and can be measured directly from Lorentz-violating observations. Our results
are relevant to the fundamental understanding of physics, and more practically,
of natural units, as well as explanations of experimental constraints in
searching for Lorentz violation.Comment: 10 latex pages, final version for journal publicatio
High-fidelity interconversion between Greenberger-Horne-Zeilinger and states through Floquet-Lindblad engineering in Rydberg atom arrays
Greenberger-Horne-Zeilinger and W states feature genuine tripartite
entanglement that cannot be converted into each other by local operations and
classical communication. Here, we present a dissipative protocol for
deterministic interconversion between Greenberger-Horne-Zeilinger and W states
of three neutral Rb atoms arranged in an equilateral triangle of a
two-dimensional array. With three atomic levels and diagonal van der Waals
interactions of Rydberg atoms, the interconversion between tripartite entangled
states can be efficiently accomplished in the Floquet-Lindblad framework
through the periodic optical pump and dissipation engineering. We evaluate the
feasibility of the existing methodology using the experimental parameters
accessible to current neutral-atom platforms. We find that our scheme is robust
against typical noises, such as laser phase noise and geometric imperfections
of the atom array. In addition, our scheme can integrate the Gaussian soft
quantum control technique, which further reduces the overall conversion time
and increases the resilience to timing errors and interatomic distance
fluctuations. The high-fidelity and robust tripartite entanglement
interconversion protocol provides a route to save physical resources and
enhance the computational efficiency of quantum networks formed by neutral-atom
arrays.Comment: 18 pages, 14 figures, accepted by Physical Review Applie
Comparing the Host Galaxies of Type Ia, Type II and Type Ibc Supernovae
We compare the host galaxies of 902 supernovae, including SNe Ia, SNe II and
SNe Ibc, which are selected by cross-matching the Asiago Supernova Catalog with
the SDSS Data Release 7. We further selected 213 galaxies by requiring the
light fraction of spectral observations 15%, which could represent well the
global properties of the galaxies. Among them, 135 galaxies appear on the
Baldwin-Phillips-Terlevich diagram, which allows us to compare the hosts in
terms of star-forming, AGNs (including composites, LINERs and Seyfert 2s) and
"Absorp" (their related emission-lines are weak or non-existence) galaxies. The
diagrams related to parameters D(4000), H, stellar masses, SFRs
and specific SFRs for the SNe hosts show that almost all SNe II and most of SNe
Ibc occur in SF galaxies, which have a wide range of stellar mass and low
D(4000). The SNe Ia hosts as SF galaxies follow similar trends. A
significant fraction of SNe Ia occurs in AGNs and Absorp galaxies, which are
massive and have high D(4000). The stellar population analysis from
spectral synthesis fitting shows that the hosts of SNe II have a younger
stellar population than hosts of SNe Ia. These results are compared with those
of the 689 comparison galaxies where the SDSS fiber captures less than 15% of
the total light. These comparison galaxies appear biased towards higher
12+log(O/H) (0.1dex) at a given stellar mass. Therefore, we believe the
aperture effect should be kept in mind when the properties of the hosts for
different types of SNe are discussed.Comment: 15 pages, 9 figure
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