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Cicerone C M - - 1995
We introduce and explore a color phenomenon which requires the prior perception of motion to produce a spread of color over a region defined by motion. We call this motion-induced spread of color dynamic color spreading. The perception of dynamic color spreading is yoked to the perception of apparent motion: ...
Tsudzuki M - - 1995
A new plumage color mutation of Japanese quail (Coturnix japonica) was named "light down lethal" based on its light coloration of neonatal plumage and almost total mortality by 3 weeks of age. Prehatch mortality of the light down lethal was also higher (36.8%) than the wild type (8.2%). The majority ...
Theeuwes J - - 1995
The present studies investigated whether an isoluminant color change pops out, indicating that it can be detected preattentively in parallel. The results of Experiment 1 show that an abrupt color change presented on an equiluminant background does not pop out. However, when the color change is accompanied by a small ...
Martin T Z - - 1995
The Galileo Photopolarimeter Radiometer experiment made direct photometric observations at 678 and 945 nanometers of several comet Shoemaker-Levy 9 fragments impacting with Jupiter. Initial flashes occurred at (fragment G) 18 July 1994 07:33:32, (H) 18 July 19:31:58, (L) 19 July 22:16:48, and (Q1) 20 July 20:13:52 [equivalent universal time coordinated ...
Cameron D L - - 1995
30 male and 13 female licensed drivers were given a static reaction-time test for Donders Type B reactions to the onset of automotive rear lights. The lights were displayed as by conventional systems and by a new color-specific method referred to as the "Red Light Means Stop approach." When subjects ...
De Weert C M - - 1995
A pincushion formed by four arcs on a gray background looks darker when the arcs are black, and lighter when the arcs are white. Yet, a matching-experiment shows that this difference is relative. Whereas the apparently darker pincushion requires a matching luminance that is lower than the background luminance (i.e. ...
Law M B - - 1995
The inhibition of return of visual attention based on stimulus color was examined in three experiments. In the first experiment, a discrete trial paradigm showed that subjects were slower to detect a color patch if the color matched that of a patch presented earlier in the same location. Experiment 2 ...
Morriss R H - - 1995
Participants adjusted the saturation of one rectangular color stimulus so that it appeared to match the saturation of another rectangular color stimulus for stimulus pairs of different relative areas. In Experiment 1, in which stimuli of complementary colors were used, higher saturation stimuli were consistently chosen for large areas to ...
Watanabe T - - 1995
The McCollough orientation-contingent color aftereffect could be equally well elicited by either a full test pattern of black and white stripes or a similar test pattern that was largely occluded by white surfaces, provided the latter stripes were made to appear as through continuing under the white surfaces--by means of ...
Zhu P - - 1995
A display hologram of an object can be recorded and reconstructed in three primary colors if the angular selectivity of volume recording media is exploited. Three holograms are recorded in the same medium, each at a different primary color. These three holograms are reconstructed by simultaneous illumination of the hologram ...
Courtney S M - - 1995
A biologically-based neural network simulation is used to analyze the contributions to color perception of each of several processing steps in the visual system from the retina to cortical area V4. We consider the effects on color constancy and color induction of adaptation, spectral opponency, non-linearities including saturation and rectification, ...
Losada M A - - 1995
We assessed the contribution of off-frequency looking for pattern detection and obtained bandwidths for chromatic and luminance mechanisms in conditions free from this effect. We used a simultaneous spatial masking technique with Gaussian enveloped sinusoidal test stimuli (0.5 cycle/deg) and filtered one-dimensional static-noise masks whose spectral power was uniformly distributed ...
Glick K L - - 1995
Ideally, a cosmetic restoration should be indistinguishable from the surrounding unrestored dentition. The cosmetic dentist faces the challenging task of creating the restoration using materials that do not possess the light-transmitting properties of natural tooth structures. A thorough knowledge of the physical and physiologic properties of light, color production and ...
Smith V C - - 1995
There is a growing use of color monitor systems in visual research and a parallel growth in the use of cone-excitation space to define stimuli and to report data. Color specification in monitor systems is accomplished by combination of the phosphor chromaticities. The effect of interobserver variation on color specification ...
La Heij W - - 1995
Color-color interference refers to the finding that the naming of a target color is hampered by the simultaneous presentation of an incongruent distractor color somewhere else in the visual field. This interference effect has been attributed to an imperfect input selection (selection-for-processing). We test an alternative account in which it ...
Wei J - - 1995
Changes in color appearance caused by chromatic adaptation were measured with a wide range of adapting fields. Observers viewed a 39'-55' annular test field composed of an admixture of lights from the red phosphor and the green phosphor of a CRT. The annular mixture field was centered and superimposed upon ...
Courtney S M - - 1995
A biologically-based multistage neural network is presented which produces color constant responses to a variety of color stimuli. The network takes advantage of several mechanisms in the human visual system, including retinal adaptation, spectral opponency, and spectrally-specific long-range inhibition. This last stage is a novel mechanism based on cells which ...
Eskew R T RT - - 1994
The temporal properties of the red-green chromatic mechanism were studied with red and green equiluminant flashes of 1 deg diameter presented in the center of a bright (800-3000 td) yellow adapting field. A subthreshold 200 msec red or green flash makes an immediately subsequent, suprathreshold yellow luminance flash appear tinged ...
Steen R - - 1994
PURPOSE: To determine the effect of disability glare (DG) upon luminance and color contrast sensitivity for young and elderly subjects. METHODS: DG was defined as the difference in contrast sensitivity with and without the presence of a glare source. Isoluminant color gratings were modulated either along a red-green (R-G) or ...
Ooi T L - - 1994
Psychophysical increment thresholds were compared for periods of phenomenological dominance or suppression produced by different stimulation of the two eyes. Three experimental procedures were used; binocular rivalry, permanent suppression and flash suppression. The amount of suppression produced by each procedure was evaluated under conditions intended to accentuate color or luminance ...
Kim R Y - - 1994
PURPOSE: To define further the syndrome of cutaneous melanoma-associated retinopathy, of which only five affected patients have been reported previously. METHODS: Three men with melanoma-associated retinopathy were examined and studied electrophysiologically. Two were studied in detail psychophysically. RESULTS: Visual symptoms consisted of flickering black and white spots, shimmering patches of ...
Bude R O - - 1994
PURPOSE: To compare power Doppler sonography with color Doppler sonography in the depiction of normal intrarenal vasculature. MATERIALS AND METHODS: Twenty kidneys in 10 healthy, nonobese subjects were studied with color Doppler and power Doppler sonography at 3.5 MHz and a pulse repetition frequency of 800 Hz. The color gain ...
Haug B A - - 1994
We used the computerized Moorfield Vision System to demonstrate specific increases in various perceptual visual thresholds in idiopathic Parkinson's syndrome. Fifteen patients were compared to 13 age-matched normals. Motion detection was impaired maximally (2 p < 0.01 and better in two-tailed t test) at luminance contrasts of 3-7%. Stimulus was ...
Webster M A - - 1994
Most models of color vision assume that signals from the three classes of cone receptor are recoded into only three independent post-receptoral channels: one that encodes luminance and two that encode color. Stimuli that are equated for their effects on two of the channels should be discriminable only to the ...
Smith G - - 1994
The ability to recognize and discriminate colors under full-moon light was measured Color naming was performed at three sizes (0.5°, 2°, and 4°) by the use of one white and six colored chips that spanned the spectrum at two levels of saturation. The results show that correct color recognition is ...
Gordon J - - 1994
Most of the fully elaborated systems for describing color appearance rely on matching to samples from some standard set. Since this is not satisfactory in all situations, various forms of direct linguistic description have been used, ranging from color naming to continuous numerical scaling of sensations. We have developed and ...
Iverson G - - 1994
We examine conditions under which the spectral properties of lights and surfaces may be recovered by a trichromatic visual system that uses bilinear models. We derive criteria for perfect recovery, formulated in terms of invariant properties of model matrices, for situations in which either two or three lights are shown ...
Scott R P - - 1994
At 30 weeks of age, Large White turkey hens were exposed to blue (B), green (G), red (R), or incandescent (I) light equalized at a photon output of 9.0 microM/sec/m2. Blood cell counts, stress status, and immune function were evaluated after 15 and 23 weeks of exposure to the light ...
Forsberg F - - 1994
Intravenously injected ultrasonic contrast agents making use of encapsulated gas microbubbles have excellent clinical potential for both color and spectral Doppler studies. However, a number of artifacts are associated with sonographic contrast agent measurements. Three artifacts were identified: (1) color "blooming," (2) increased maximum Doppler shift, and (3) spectral "bubble ...
Kawabata M - - 1994
We present a new type of photopolymer system for recording reflection holograms. The photopolymer system with radical and cationic photopolymerization controlled by the wavelength of light gives us enhanced diffraction efficiencies and a balanced recording sensitivity (20-60 mJ/cm(2)) in the blue to red region of the spectrum. In color hologram ...
Ali A - - 1994
The attraction of adult Chironomus salinarius to incandescent 3-W lamps of 7 different colors used in CDC traps was studied on a small island in the lagoon of Venice, Italy. An ANOVA indicated that the lamp type was a highly significant (P < 0.01) factor associated with differences in light ...
Sanocki E - - 1994
The dual Rayleigh-type color match is the ratio of 621 nm light to 550 nm light that in admixture matches 586 nm light, divided by the ratio of 667 nm light to 550 nm light that in admixture matches 586 nm light. Compared to the classical Rayleigh match, the dual-match ...
Kawabata Y - - 1994
The present study showed that the spatial integration area was expanded even if the background energy was increased, provided that the background consisted of the two colors which were opponent to each other (red/green). This expansion was not found for the subjects with dichromatic color vision even though the same ...
Wesner M F - - 1994
Light at the boundary of a uniform test field (contrast) has a qualitatively different effect on color perception than light in more remote noncontiguous regions (context). Basic properties of color perception with contextual short-wavelength light are assessed here with a 1 degree test field surrounded by either contiguous or noncontiguous ...
Bäuml K H - - 1994
A theory about how changes in the illuminant affect the color appearance of objects must specify how the visual system's adjustments to illuminant changes vary with the surface collection in a scene. I report an experiment designed to investigate this issue. The stimuli were CRT simulations of flat matte surfaces ...
Shackelford S D - - 1994
The objectives of this experiment were to characterize longissimus muscle color, texture, and firmness for beef carcasses of diverse biological types and to determine the genetic parameters of lean color, texture, and firmness. The carcasses (n = 3,641) used in this experiment were from steers produced by mating Angus, Brahman, ...
Ito S - - 1994
A new plumage color mutant, orange, in Japanese quail (Coturnix japonica) was characterized by the same plumage pattern as in the wild type but with diluted pigmentation on the whole body. Light reddish-brown and light black are predominant instead of heavy brown and heavy black in the wild type. Although ...
Watanuki S - - 1994
To investigate the effects of body temperature decrease which occurred along with cold exposure and menstrual cycle, on color sensation, differential limen (DL) and points of subjectively equality (PSE) or red, green, blue and gray colors were measured by using methods of limit in six young female subjects. also, the ...
Takiwaki H - - 1994
Two types of portable reflectance instruments, tristimulus colorimeters (Chroma Meter CR-200) and narrow-band spectrophotometers (Dermaspectrometer), have recently become available for the quantification of skin color. In order to know the difference and the relationship between the different color systems, the CIE L*a*b* system and the erythema melanin (E/M) indices, respectively, ...
Yuk K C - - 1994
We present a simple method of determining the absolute order of shadow moiré fringes by using two differently colored light sources. This technique is based on the periodic color structures generated by superimposing two moiré patterns with different colors.
Häusler G - - 1993
We discuss a three-dimensional sensor that combines coded illumination and triangulation. The sensor supplies the distance of ~ 250,000 object pixels (TV format) in 40 ms (one single TV frame period). Themethod is based on the following principle: a color spectrum of a white-light source is imaged onto the object ...
Gorea A - - 1993
We present psychological experiments that reveal two motion systems, a specific and an unspecific one. The specific system prevails at medium to high temporal frequencies. It comprises at least two separate motion pathways that are selective for color and for luminance and that do not interact until after the motion ...
Poirson A B - - 1993
We have measured how color appearance of square-wave bars varies with stimulus strength and spatial frequency. Observers adjusted the color of a uniform patch to match the color appearance of the bars in square-wave patterns. We used low-to-moderate square-wave patterns, from 1 to 8 cycles per degree (c/deg). The matches ...
Gur M - - 1993
We have previously argued that unless color and luminance are shown to be processed independently, using isoluminant stimuli may not reveal the full contribution of color to visual functioning. Here we study the interaction of color and luminance in a task, Mach bands detection and perceived brightness, where color by ...
Stoerig P - - 1993
Spatial summation curves were determined in the circumscribed visual-field defects of five patients with blindsight. Under light-adapted conditions that favor the color-opponent system, increment thresholds for white and red targets presented on a white background were measured as a function of stimulus size which ranged from 9-110 min arc. In ...
Hasson H M - - 1993
A new endoscopic camera that does not require a viewing rod lens endoscope has been developed. It consists of a 10-mm metal tube and handle containing a distally placed camera chip. The distal chip endoscope is attached to a combined camera light source and processor by a well-protected cable. Due ...
Bajpai O P - - 1993
A white-light optical signal-processing technique is presented to color encode directional edges present in discrete-tone black and white imagery in real time with colors that are available in the white-light source.
Arend L E - - 1993
Does the light coming from a surface (as opposed to the surface color) appear the same after adaptation to a new illumination as it did before the illumination changed? Many answers have been proposed over the past century, but all have been unsatisfactory. The main measurement problem is to provide ...
D'Zmura M - - 1993
Changing a scene's illuminant causes the chromatic properties of reflected lights to change. This change in the lights from surfaces provides spectral information about surface reflectances and illuminants. We examine conditions under which these properties may be recovered by using bilinear models. Necessary conditions that follow from comparing the number ...
Nothdurft H C - - 1993
Arrays of lines or blobs were used to investigate the role of features vs feature contrast in preattentive vision. This study continues earlier work on orientation cues and extends it into the dimensions of motion and color. Tests were performed on patterns displaying continuous feature gradients, i.e. continuous variation, from ...
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