Search results for " mask"
showing 10 items of 171 documents
Study on the transient characteristic in the human visual system using masking experiments
1979
In this paper the visual masking effect is interpreted on the basic of the transient characteristic in two dimensional neuronal networks. The study investigates the suitability of the effect for use as a measurement method. It is shown that the stimulus distribution in space can be scanned at different points in time and that various dynamic characteristic values of the system can be measured.
Rank-order and morphological enhancement of image details with an optoelectronic processor.
2010
In all-optical processors, enhancement of image details is the result of high-pass filtering. We describe an optoelectronic processor in which detail enhancement results from the digitally calculated difference between an original input image and its low-pass filtered version. The low-pass filtering is realized through the rank-order median and the morphological opening and closing operations calculated by use of the optical convolver. It is shown that the normalized difference between the morphological white and black top hats enhances bright and dark image details analogously to the rank-order unsharp masking.
On the role of the upper part of words in lexical access: evidence with masked priming.
2012
More than 100 years ago, Huey (1908) indicated that the upper part of words was more relevant for perception than the lower part. Here we examined whether mutilated words, in their upper/lower portions (e.g., , , , ), can automatically access their word units in the mental lexicon. To that end, we conducted four masked repetition priming experiments with the lexical decision task. Results showed that mutilated primes produced a sizeable masked repetition priming effect. Furthermore, the magnitude of the masked repetition priming effect was greater when the upper part of the primes was preserved than when the lower portion was preserved –this was the case not only when the mutilated words we…
LMA Supreme™ and Ambu® AuraGain™ in anesthetized adult patients: a prospective observational study
2017
BACKGROUND Second-generation laryngeal masks with gastric access are increasingly used in daily practice and expand the indications for laryngeal masks in the OR. Only limited data exist comparing different types of laryngeal masks. We investigated the second-generation laryngeal masks LMA Supreme™ and Ambu® AuraGain™ in a clinical setting. We hypothesized that the two devices would be comparable in terms of success rate and airway complications. METHODS After approval from the local ethics committee, data were collected in a prospective trial. Endpoints were success rate, time to insertion and airway morbidity. Anesthesiologists used either the Supreme (Teleflex Medical GmbH) or Gain (Ambu…
Measurement of matter-antimatter differences in beauty baryon decays
2017
Differences in the behaviour of matter and antimatter have been observed in $K$ and $B$ meson decays, but not yet in any baryon decay. Such differences are associated with the non-invariance of fundamental interactions under the combined charge-conjugation and parity transformations, known as $C\!P$ violation. Using data from the LHCb experiment at the Large Hadron Collider, a search is made for $C\!P$-violating asymmetries in the decay angle distributions of $\Lambda^0_b$ baryons decaying to $p\pi^-\pi^+\pi^-$ and $p\pi^-K^+K^-$ final states. These four-body hadronic decays are a promising place to search for sources of $C\!P$ violation both within and beyond the Standard Model of particle…
Far-field light imaging in the presence of atmospheric turbulence with rotating anti-phase apertures: Theoretical investigation
2017
We investigated the diffraction of far-field light objects in the presence of turbulence formed by an optical system with a rotating anti-phase mask. This mask facilitates to detect the position of faint companion in every direction around the bright companion. In the presence of atmospheric turbulence, diffraction images of distant objects are beyond the diffraction limits, the proposed phase shift mask has a merit to compensate the turbulence results high contrast astronomical imaging under partially coherent light illumination and it is proficient to increase the resolution limits in a Sparrow criterion sense. In this approach, we demonstrated the mask fabrication in laboratory condition…
Influence of gravity vector on eye movement elicited by linear acceleration.
1991
When the body/head motion is sensed by otolith organs, they respond not only to the resultant acceleration of the motion but also to the gravitational force. We investigated the influence of the gravity vector on the otolithic-ocular reflex caused by motion in normal subjects. The sled type linear accelerator, moving back and forth with a frequency of 0.25 Hz and an amplitude of 2 m, generated right-left linear acceleration with a maximum magnitude of 0.5 g. We tested every subject under seven different postures: 1) 135 degrees forward tilted (F.T.), 2) 90 degrees F.T., 3) 45 degrees F.T., 4) upright sitting, 5) 45 degrees backward tilted (B.T.), 6) 90 degrees B.T., and 7) 135 degrees B.T. …
Electrophysiological Correlates of Intensity Resolution Under Forward Masking
2010
Nonsimultaneous masking can severely impair auditory intensity resolution, but the effect strongly depends on the stimulus configuration. For example, an intense forward masker causes a pronounced impairment in intensity resolution for standards presented at intermediate levels, but not for standards presented at low and high levels, resulting in a midlevel hump pattern (Zeng et al., Hear Res 55:223-230, 1991). Several aspects of the phenomenon cannot be explained by mechanisms in the auditory periphery. For instance, backward maskers cause midlevel humps at least as large as the humps caused by forward maskers. The present experiment was aimed at studying the relation between the effects o…
There is no clam with coats in the calm coast: delimiting the transposed-letter priming effect.
2009
In this article, we explore the transposed-letter priming effect (e.g., jugde–JUDGE vs. jupte–JUDGE), a phenomenon that taps into some key issues on how the brain encodes letter positions and has favoured the creation of new input coding schemes. However, almost all the empirical evidence from transposed-letter priming experiments comes from nonword primes (e.g., jugde–JUDGE). Indeed, previous evidence when using word–word pairs (e.g., causal–CASUAL) is not conclusive. Here, we conducted five masked priming lexical decision experiments that examined the relationship between pairs of real words that differed only in the transposition of two of their letters (e.g., CASUAL vs. CAUSAL). Result…
Do transposed-letter similarity effects occur at a prelexical phonological level?
2006
Nonwords created by transposing two letters (e.g., RELOVUTION) are very effective at activating the lexical representation of their base words (Perea & Lupker, 2004). In the present study, we examined whether the nature of transposed-letter (TL) similarity effects was purely orthographic or whether it could also have a phonological component. Specifically, we examined transposed-letter similarity effects for nonwords created by transposing two nonadjacent letters (e.g., relovución– REVOLUCIÓN) in a masked form priming experiment using the lexical decision task (Experiment 1). The controls were (a) a pseudohomophone of the transposed-letter prime ( relobución– REVOLUCIÓN; note that B an…