scholarly journals The mean matters: Effects of statistically defined nonspeech spectral distributions on speech categorization

2006 ◽  
Vol 120 (5) ◽  
pp. 2801-2817 ◽  
Author(s):  
Lori L. Holt
Keyword(s):  
The Mean ◽  
Spectral Distributions ◽  
Speech Categorization

scholarly journals Comparison of silorane and methacrylate-based composite resins on the curing light transmission

2010 ◽  
Vol 21 (6) ◽  
pp. 538-542 ◽  
Author(s):  
Ricardo Danil Guiraldo ◽  
Simonides Consani ◽  
Rafael Leonardo Xediek Consani ◽  
Sandrine Bittencourt Berger ◽  
Wilson Batista Mendes ◽  
...  
Keyword(s):  
Composite Resin ◽  
Light Transmission ◽  
Knoop Hardness ◽  
Composite Resins ◽  
Power Meter ◽  
Light Curing ◽  
Curing Light ◽  
The Mean ◽  
Spectral Distributions ◽  
The Difference

The aim of this study was to investigate the influence of different composite resins - Filtek P90 (silorane-based composite) and Heliomolar (methacrylate-based composite) - on light transmission and decrease in Knoop hardness between the bottom and top of cured specimens. The irradiance of a light-curing unit (LCU) was measured with a power meter (Ophir Optronics; 900 mw/cm2) and spectral distributions were obtained using a spectrometer (USB 2000). Twenty standardized cylindrical specimens (2 mm thick x 7 mm diameter) of each composite resin were obtained by curing using the LCU for 40 s. Light energy transmission through the composite was calculated (n=10). The Knoop hardness number for each surface was recorded as the mean of 3 indentations. The difference in Knoop hardness between the top and bottom (DKH) of the same specimen was calculated (n=10). The irradiance of light that passed through Filtek P90 (272 mW/cm2) was not significantly greater than that the passed through Heliomolar (271 mW/cm2). The DKH of Filtek P90 (25%) was significantly higher than that of Heliomolar (12%). There was a greater degree of subsurface polymerization of the methacrylate-based composite compared to the silorane-based composite.

Temporally Nonadjacent Nonlinguistic Sounds Affect Speech Categorization

2005 ◽  
Vol 16 (4) ◽  
pp. 305-312 ◽  
Author(s):  
Lori L. Holt
Keyword(s):  
Speech Perception ◽  
Context Effects ◽  
Sine Wave ◽  
Speech Stimulus ◽  
Spectral Information ◽  
Statistical Distributions ◽  
Nonspeech Sounds ◽  
Spectral Distributions ◽  
Context Dependent ◽  
Speech Categorization

Speech perception is an ecologically important example of the highly context-dependent nature of perception; adjacent speech, and even nonspeech, sounds influence how listeners categorize speech. Some theories emphasize linguistic or articulation-based processes in speech-elicited context effects and peripheral (cochlear) auditory perceptual interactions in non-speech-elicited context effects. The present studies challenge this division. Results of three experiments indicate that acoustic histories composed of sine-wave tones drawn from spectral distributions with different mean frequencies robustly affect speech categorization. These context effects were observed even when the acoustic context temporally adjacent to the speech stimulus was held constant and when more than a second of silence or multiple intervening sounds separated the nonlinguistic acoustic context and speech targets. These experiments indicate that speech categorization is sensitive to statistical distributions of spectral information, even if the distributions are composed of nonlinguistic elements. Acoustic context need be neither linguistic nor local to influence speech perception.

Rhythmic variations in R-R interval during sleep and wakefulness in puppies and dogs

1984 ◽  
Vol 247 (1) ◽  
pp. H67-H73
Author(s):  
G. G. Haddad ◽  
H. J. Jeng ◽  
S. H. Lee ◽  
T. L. Lai
Keyword(s):  
Low Frequency ◽  
Total Power ◽  
Short Term ◽  
Sleep State ◽  
Quiet Sleep ◽  
Low Frequencies ◽  
Low Frequency Oscillations ◽  
Percent Contribution ◽  
The Mean ◽  
Spectral Distributions

We studied the short-term oscillations in the R-R interval in five puppies at 4 wk of age and five adult dogs during sleep and wakefulness. The R-R interval was measured using an R-R preprocessor, and respiration was recorded using barometric plethysmography. Puppies showed much smaller fluctuations in the R-R interval (SD between 6 and 40 ms) than adult dogs (SD between 124 and 367 ms) in both rapid eye movement (REM) and quiet sleep. Spectral analysis demonstrated that these oscillations were primarily of low frequencies, and the contribution of respiratory sinus arrythmia (RSA) to total power was low. In contrast, in adult dogs during sleep, the spectral distributions were peaked in frequency bands corresponding to mean respiratory rate, and the percent contribution of low frequencies to power was small. Furthermore, the mean R-R interval was considerably larger during expiration than during inspiration in adult dogs (showing 20-140% increase), but not in puppies (showing only -0.4 to 4.4% increase). We conclude that 1) the mechanisms responsible for RSA mature postnatally in the dog; 2) the magnitude of RSA depends on the state of consciousness in the adult dog, being greater in sleep than during wakefulness; and 3) low-frequency oscillations, not related to breathing and independent of sleep state, characterize the variations in the R-R interval in early life but are insignificant in the adult dog.

Photo-electric Hβ and uvby photometry

1966 ◽  
Vol 24 ◽  
pp. 170-180
Author(s):  
D. L. Crawford
Keyword(s):  
Narrow Band ◽  
Line Strength ◽  
Interference Filter ◽  
B Stars ◽  
Relative Line ◽  
The Mean ◽  
F Stars ◽  
Two Parameters ◽  
Filter Photometry ◽  
The Continuum

Early in the 1950's Strömgren (1, 2, 3, 4, 5) introduced medium to narrow-band interference filter photometry at the McDonald Observatory. He used six interference filters to obtain two parameters of astrophysical interest. These parameters he calledlandc, for line and continuum hydrogen absorption. The first measured empirically the absorption line strength of Hβby means of a filter of half width 35Å centered on Hβand compared to the mean of two filters situated in the continuum near Hβ. The second index measured empirically the Balmer discontinuity by means of a filter situated below the Balmer discontinuity and two above it. He showed that these two indices could accurately predict the spectral type and luminosity of both B stars and A and F stars. He later derived (6) an indexmfrom the same filters. This index was a measure of the relative line blanketing near 4100Å compared to two filters above 4500Å. These three indices confirmed earlier work by many people, including Lindblad and Becker. References to this earlier work and to the systems discussed today can be found in Strömgren's article inBasic Astronomical Data(7).

A one-dimensional self-gravitating stellar gas

1966 ◽  
Vol 25 ◽  
pp. 46-48 ◽  
Author(s):  
M. Lecar
Keyword(s):  
Gravitational Field ◽  
Phase Space ◽  
Motion Picture ◽  
Space Distribution ◽  
Two Dimensional ◽  
One Dimensional ◽  
Phase Space Distribution ◽  
Dimensional Phase Space ◽  
The Mean

“Dynamical mixing”, i.e. relaxation of a stellar phase space distribution through interaction with the mean gravitational field, is numerically investigated for a one-dimensional self-gravitating stellar gas. Qualitative results are presented in the form of a motion picture of the flow of phase points (representing homogeneous slabs of stars) in two-dimensional phase space.

The motion of a lunar orbiter

1966 ◽  
Vol 25 ◽  
pp. 373
Author(s):  
Y. Kozai
Keyword(s):  
Degrees Of Freedom ◽  
Dimensional Space ◽  
Artificial Satellite ◽  
Equations Of Motion ◽  
Triaxial Ellipsoid ◽  
The Moon ◽  
Secular Motion ◽  
The Earth ◽  
Close Satellite ◽  
The Mean

The motion of an artificial satellite around the Moon is much more complicated than that around the Earth, since the shape of the Moon is a triaxial ellipsoid and the effect of the Earth on the motion is very important even for a very close satellite.The differential equations of motion of the satellite are written in canonical form of three degrees of freedom with time depending Hamiltonian. By eliminating short-periodic terms depending on the mean longitude of the satellite and by assuming that the Earth is moving on the lunar equator, however, the equations are reduced to those of two degrees of freedom with an energy integral.Since the mean motion of the Earth around the Moon is more rapid than the secular motion of the argument of pericentre of the satellite by a factor of one order, the terms depending on the longitude of the Earth can be eliminated, and the degree of freedom is reduced to one.Then the motion can be discussed by drawing equi-energy curves in two-dimensional space. According to these figures satellites with high inclination have large possibilities of falling down to the lunar surface even if the initial eccentricities are very small.The principal properties of the motion are not changed even if plausible values ofJ3andJ4of the Moon are included.This paper has been published in Publ. astr. Soc.Japan15, 301, 1963.

On nearly-commensurable periods in the restricted problem of three bodies, with calculations of the long-period variations in the interior 2:1 case

1966 ◽  
Vol 25 ◽  
pp. 197-222 ◽  
Author(s):  
P. J. Message
Keyword(s):  
Periodic Solution ◽  
Periodic Solutions ◽  
Large Amplitude ◽  
Restricted Problem ◽  
Small Amplitude ◽  
Minor Planets ◽  
Long Period ◽  
Numerical Integrations ◽  
Period Variations ◽  
The Mean

An analytical discussion of that case of motion in the restricted problem, in which the mean motions of the infinitesimal, and smaller-massed, bodies about the larger one are nearly in the ratio of two small integers displays the existence of a series of periodic solutions which, for commensurabilities of the typep+ 1:p, includes solutions of Poincaré'sdeuxième sortewhen the commensurability is very close, and of thepremière sortewhen it is less close. A linear treatment of the long-period variations of the elements, valid for motions in which the elements remain close to a particular periodic solution of this type, shows the continuity of near-commensurable motion with other motion, and some of the properties of long-period librations of small amplitude.To extend the investigation to other types of motion near commensurability, numerical integrations of the equations for the long-period variations of the elements were carried out for the 2:1 interior case (of which the planet 108 “Hecuba” is an example) to survey those motions in which the eccentricity takes values less than 0·1. An investigation of the effect of the large amplitude perturbations near commensurability on a distribution of minor planets, which is originally uniform over mean motion, shows a “draining off” effect from the vicinity of exact commensurability of a magnitude large enough to account for the observed gap in the distribution at the 2:1 commensurability.

the effects of resonance with Jupiter in the system of short-period comets

1974 ◽  
Vol 22 ◽  
pp. 193-203
Author(s):  
L̆ubor Kresák
Keyword(s):  
Structural Effects ◽  
Order Resonance ◽  
Mean Motion ◽  
Short Period ◽  
The Mean ◽  
Compound Effect ◽  
Low Order

AbstractStructural effects of the resonance with the mean motion of Jupiter on the system of short-period comets are discussed. The distribution of mean motions, determined from sets of consecutive perihelion passages of all known periodic comets, reveals a number of gaps associated with low-order resonance; most pronounced are those corresponding to the simplest commensurabilities of 5/2, 2/1, 5/3, 3/2, 1/1 and 1/2. The formation of the gaps is explained by a compound effect of five possible types of behaviour of the comets set into an approximate resonance, ranging from quick passages through the gap to temporary librations avoiding closer approaches to Jupiter. In addition to the comets of almost asteroidal appearance, librating with small amplitudes around the lower resonance ratios (Marsden, 1970b), there is an interesting group of faint diffuse comets librating in characteristic periods of about 200 years, with large amplitudes of about±8% in μ and almost±180° in σ, around the 2/1 resonance gap. This transient type of motion appears to be nearly as frequent as a circulating motion with period of revolution of less than one half that of Jupiter. The temporary members of this group are characteristic not only by their appearance but also by rather peculiar discovery conditions.

Contrast of Filament Bright Rims

1994 ◽  
Vol 144 ◽  
pp. 365-367
Author(s):  
E. V. Kononovich ◽  
O. B. Smirnova ◽  
P. Heinzel ◽  
P. Kotrč
Keyword(s):  
High Altitude ◽  
Line Profile ◽  
Line Center ◽  
Magnetic Structures ◽  
The Mean

AbstractThe Hα filtergrams obtained at Tjan-Shan High Altitude Observatory near Alma-Ata (Moscow University Station) were measured in order to specify the bright rims contrast at different points along the line profile (0.0; ± 0.25; ± 0.5; ± 0.75 and ± 1.0 Å). The mean contrast value in the line center is about 25 percent. The bright rims interpretation as the bases of magnetic structures supporting the filaments is suggested.

Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

1997 ◽  
Vol 161 ◽  
pp. 197-201 ◽  
Author(s):  
Duncan Steel
Keyword(s):  
Probability Distributions ◽  
Regions Of Interest ◽  
Significant Fraction ◽  
Organic Chemicals ◽  
Impact Speed ◽  
The Mean ◽  
The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

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