scholarly journals Object Clusters or Spectral Energy? Assessing the Relative Contributions of Image Phase and Amplitude Spectra to Trypophobia

2019 ◽  
Author(s):  
R. Nathan Pipitone ◽  
Chris DiMattina
Keyword(s):  
Amplitude Spectrum ◽  
Spectral Energy ◽  
Visual Comfort ◽  
Visual Discomfort ◽  
Comfort Levels ◽  
Spatial Frequencies ◽  
Amplitude Spectra ◽  
Small Clusters ◽  
Full Factorial ◽  
Phase Spectra

Trypophobia refers to the visual discomfort experienced by some people when viewing clustered patterns (e.g., clusters of holes). Trypophobic images deviate from the 1/f amplitude spectra typically characterizing natural images by containing excess energy at mid-range spatial frequencies. While recent work provides partial support for the idea of excess mid-range spatial frequency energy causing visual discomfort when viewing trypophobic images, a full factorial manipulation of image phase and amplitude spectra has yet to be conducted. Here, we independently manipulated the phase and amplitude spectra of 31 Trypophobic images using a standard Fast Fourier Transform (FFT). Participants rated the four different versions of each image for levels of visual comfort, and completed the Trypophobia Questionnaire (TQ). Images having the original phase spectra intact (with either original or 1/f amplitude) explained the most variance in comfort ratings and were rated lowest in comfort. However, images with the original amplitude spectra but scrambled phase spectra were rated higher in comfort, with a smaller amount of variance in comfort attributed to the amplitude spectrum. Participant TQ scores correlated with comfort ratings only for images having the original phase spectra intact. There was no correlation between TQ scores and comfort levels when participants viewed the original amplitude / phase-scrambled images. Taken together, the present findings show that the phase spectrum of trypophobic images, which determines the pattern of small clusters of objects, plays a much larger role than the amplitude spectrum in determining visual comfort.

Determination of crustal thickness from spectral behavior of SH waves

1969 ◽  
Vol 59 (3) ◽  
pp. 1247-1258
Author(s):  
Abou-Bakr K. Ibrahim
Keyword(s):  
Amplitude Spectrum ◽  
Body Waves ◽  
Multiple Reflections ◽  
Matrix Formulation ◽  
Sh Waves ◽  
Crustal Model ◽  
Amplitude Spectra ◽  
Phase Spectra ◽  
Zero Phase

abstract The amplitude spectrum obtained from Haskell's matrix formulation for body waves travelling through a horizontally layered crustal model shows a sequence of minima and maxima. It is known that multiple reflections within the crustal layers produce constructive and destructive interferences, which are shown as maxima and minima in the amplitude spectrum. Analysis of the minima in the amplitude spectra, which correspond to zero phase in the phase spectra, enables us to determine the thickness of the crust, provided the ratio of wave velocity in the crust to velocity under the Moho is known.

Spectra of S-waves radiated from bilateral fracture

1967 ◽  
Vol 57 (1) ◽  
pp. 39-54
Author(s):  
J. C. Savage
Keyword(s):  
Amplitude Spectrum ◽  
Regular Sequence ◽  
Time Function ◽  
Source Time Function ◽  
S Waves ◽  
Amplitude Spectra ◽  
Bilateral Fracture ◽  
Tensile Fractures ◽  
Wave Trains ◽  
Phase Spectra

abstract The phase and amplitude spectra of the S waves radiated from five different bilateral, tensile fractures in two-dimensional models are discussed. Two S waves, radiated in approximately opposite directions, were recorded for each fracture. The amplitude spectra display the regular sequence of holes first explained by Ben-Menahem. The phase spectra display a phase jump of π radians associated with each hole in the corresponding amplitude spectrum. The phase of the source-time function was extracted from the phase spectra; it is consistent with a representation of the source-time function by a ramp function of 14 μsec duration. An explanation of the observed spectra is given in terms of interference between the initial and stopping phases of the radiated signal. From this viewpoint Ben-Menahem's directivity method is seen as a procedure for detecting the stopping phase in dispersed wave trains. Finally, it is suggested that the analyses by Ben-Menahem and Toksöz of the phase spectra of the Kamchatka 1952 and Alaska 1958 earthquakes have not properly taken account of the phase jumps in the spectra.

On: “Mineral discrimination and removal of inductive coupling with multifrequency IP” by W. H. Pelton, S. H. Ward, P. G. Hallof, W. R. Sill, and P. H. Nelson (GEOPHYSICS, 43, 588–609).

Geophysics ◽  
1984 ◽  
Vol 49 (9) ◽  
pp. 1556-1557
Author(s):  
Heikki Soininen
Keyword(s):  
Apparent Resistivity ◽  
Dispersion Model ◽  
Constant Factor ◽  
Constant Independent ◽  
Real Constant ◽  
Frequency Range ◽  
Dilution Factor ◽  
Amplitude Spectra ◽  
Polarizable Body ◽  
Phase Spectra

The authors discussed the behavior of the resistivity spectra by means of the Cole‐Cole dispersion model. They also discussed the corrections with which the petrophysical resistivity spectrum can be reduced into an apparent resistivity spectrum caused by a polarizable body embedded in an unpolarizable environment. The application of the Cole‐Cole dispersion model is a marked step forward in spectral IP analysis. However, closer attention must be paid to the assumptions and approaches on which the authors base the relations between the petrophysical and apparent spectra. The authors based their relations between the true and apparent spectra on the use of the dilution factor [Formula: see text]. In accordance with the definition by Seigel (1959), they assumed that [Formula: see text] is a real constant (independent of frequency) over the whole frequency range under consideration. First consider the justification for the assumption of the existence of a constant factor [Formula: see text] in the light of an example calculated for phase spectra. Similar considerations could also be made with the aid of amplitude spectra.

The Effect of Directional Spreading on Interaction of Focused Wave Groups With a Cylinder

2004 ◽  
Author(s):  
Eugeny V. Buldakov ◽  
Rodney Eatock Taylor ◽  
Paul H. Taylor
Keyword(s):  
Numerical Solutions ◽  
Amplitude Spectrum ◽  
Wave Group ◽  
Helmholtz Equations ◽  
Incoming Wave ◽  
Wave Groups ◽  
Practical Applications ◽  
Amplitude Spectra ◽  
Focused Wave ◽  
Focused Wave Group

The problem of diffraction of a directionally spread focused wave group by a bottom-seated circular cylinder is considered from the view point of second-order perturbation theory. After applying the time Fourier transform and separation of vertical variable the resulting two-dimensional non-homogeneous Helmholtz equations are solved numerically using finite differences. Numerical solutions of the problem are obtained for JONSWAP amplitude spectra for the incoming wave group with various types of directional spreading. The results are compared with the corresponding results for a unidirectional wave group of the same amplitude spectrum. Finally we discuss the applicability of the averaged spreading angle concept for practical applications.

scholarly journals Artificial Intelligence for Detecting Indoor Visual Discomfort from Facial Analysis of Building Occupants

2021 ◽  
Vol 2042 (1) ◽  
pp. 012008
Author(s):  
Hicham Johra ◽  
Rikke Gade ◽  
Mathias Østergaard Poulsen ◽  
Albert Daugbjerg Christensen ◽  
Mandana Sarey Khanie ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Image Analysis ◽  
Office Building ◽  
Visual Comfort ◽  
Feedback Control System ◽  
Visual Discomfort ◽  
Facial Analysis ◽  
Video Footage ◽  
Artificial Intelligence Algorithm ◽  
Shading Devices

Abstract Glare is a common local visual discomfort that is difficult to identify with conventional light sensors. This article presents an artificial intelligence algorithm that detects subjective local glare discomfort from the image analysis of the video footage of an office occupant’s face. The occupant’s face is directly used as a visual comfort sensor. Results show that it can recognize glare discomfort with around 90% accuracy. This algorithm can thus be at the basis of an efficient feedback control system to regulate shading devices in an office building.

scholarly journals The Influence of Typography on Algorithms That Predict the Speed and Comfort of Reading

2020 ◽  
Author(s):  
Arnold Wilkins ◽  
Katie Smith ◽  
Olivier Penacchio
Keyword(s):  
Amplitude Spectrum ◽  
Visual Comfort ◽  
Fourier Amplitude ◽  
Font Design ◽  
Spatial Regularity ◽  
Line Separation ◽  
Fourier Amplitude Spectrum

The speed with which text can be read is determined in part by the spatial regularity and similarity of vertical letter strokes as assessed by the height of the first peak in the horizontal autocorrelation of the text. The height of this peak was determined for two passages in 20 fonts. The peak was unaffected by the size of the text or its content but was influenced by the font design. Sans serif fonts usually had a lower peak than serif fonts because the presence of serifs resulted in a more even spacing of letter strokes. There were small effects of justification and font- dependent effects of font expansion and compression. The visual comfort of images can be estimated from the extent to which the Fourier amplitude spectrum conforms to 1/f. Students were asked to adjust iBooks to obtain their preferred settings of font and layout. The preference was predicted by the extent to which the Fourier amplitude spectrum approximated 1/f, which in turn was jointly affected by the design of the font, its weight and the ratio of x-height to line separation. The above algorithms can be usefully applied to any orthography to estimate likely speed and comfort of reading.

Research on the Relationship between the Depth-Movement of the Stereoscopic HDTV and Visual Comfort

2012 ◽  
Vol 239-240 ◽  
pp. 959-965
Author(s):  
Jia Xi Yu
Keyword(s):  
Research Result ◽  
Experimental Results ◽  
Visual Comfort ◽  
Visual Effects ◽  
Visual Discomfort ◽  
The Relationship

Visual comfort is an important factor that should be considered in the production of stereoscopic HDTV programs. This paper reports the result of recent researches on the relationship between visual comfort and the depth-movements, and analyses the experimental results in terms of the principle of vergence-accommodation conflict. The analysis result indicates that the depth-movements will cause viewers’ visual discomfort and fatigue, especially when the depth-movement range is large and the speed is fast. The research result is of significance to reach a balance between the realistic stereoscopic visual effects and visual comfort.

The thickness imaging of channels using multiple-frequency components analysis

2019 ◽  
Vol 7 (1) ◽  
pp. B1-B8 ◽  
Author(s):  
Yan Ye ◽  
Bo Zhang ◽  
Cong Niu ◽  
Jie Qi ◽  
Huailai Zhou
Keyword(s):  
Amplitude Spectrum ◽  
Low Frequency ◽  
Blue Color ◽  
Self Organizing Map ◽  
Multiple Frequency ◽  
Thickness Estimation ◽  
Red Color ◽  
Amplitude Spectra ◽  
Frequency Components ◽  
Components Analysis

Blending of different frequency components of seismic traces is a common way to estimate the relative time thickness of the formation. Red, blue, and green (RGB) color blending is one of the most popular blending models in analyzing multiple seismic attributes. Geologists and geophysicist interpreters typically associate low-frequency components (formations with the largest thickness value) with a red color, medium-frequency components (formations with a medium thickness value) with a green color, and high-frequency components (formations with the smallest thickness value) with a blue color for the thickness estimation of thin beds using frequency components. However, we found that the same result of RGB blending may come from different sets of three frequency components. As a result, the same blended color may correspond to several different time thicknesses. It is also very difficult to interpret the corresponding thickness of the blended colors such as white and yellow. To avoid the ambiguity of time-thickness estimation using RGB blending, we have estimated the time thickness of the thin beds using all of the frequency components in a user-defined frequency band instead of only three frequency components. Our workflow begins with the normal seismic spectral decomposition. Considering that the different reflectivity pairs with a different time thickness have a different amplitude spectrum, we then use the self-organizing map to cluster the decomposed amplitude spectra of seismic traces. We finally assign each cluster with a relative thickness by comparing the clustered results with well logs.

scholarly journals Insights from Spitzer on massive star formation in the LMC

2008 ◽  
Vol 4 (S256) ◽  
pp. 239-243
Author(s):  
Rémy Indebetouw ◽  
Barbara A. Whitney ◽  
Marta Sewilo ◽  
Thomas Robitaille ◽  
Margaret Meixner ◽  
...  
Keyword(s):  
Star Formation ◽  
Spatial Scales ◽  
Scaling Law ◽  
Spectral Energy ◽  
Stellar Content ◽  
Evolutionary State ◽  
Star Formation Activity ◽  
Dust Distribution ◽  
Small Clusters ◽  
First Time

AbstractSpitzer's sensitive mid-IR photometric surveys of the Magellanic Clouds provide a relatively extinction-free census of star formation activity, and sub-parsec resolution permits the study of individual massive protostars and small clusters. Using the SAGE survey of the LMC, we identify over 1000 massive YSO candidates by their MIR colors. Analysis of their spectral energy distributions (SEDs) constrains the stellar content and evolutionary state, beginning to realize for the first time the unique potential of the Clouds to study an entire galaxy's population of individual protostars. We probe the physics underlying the Schmidt-Kennicutt scaling law by analyzing how it begins to break down at 10–100 pc spatial scales. MIR spectroscopic surveys currently underway like SAGE-SPEC will enable us to couple the circumprotostellar dust distribution (the evolutionary state reflected in the SED) with the physical state of the gas, dust and ice.

scholarly journals An Experimental Study of Focusing Wave Generation with Improved Wave Amplitude Spectra

Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2521 ◽  
Author(s):  
Guochun Xu ◽  
Hongbin Hao ◽  
Qingwei Ma ◽  
Qinqin Gui
Keyword(s):  
Wave Energy ◽  
Wave Amplitude ◽  
Wave Spectrum ◽  
Amplitude Spectrum ◽  
Wave Frequency ◽  
Wave Crest ◽  
Wave Component ◽  
Frequency Wave ◽  
Motion Signal ◽  
Amplitude Spectra

We experimentally investigate the generating results of space-time focusing waves based on two new wave spectra, i.e., the quasi constant wave amplitude spectrum (QCWA) and the quasi constant wave steepness spectrum (QCWS), in which amplitude and steepness for each wave component can be adjusted with fixed wave energy. The wavemaker signal consists of a theoretical wavemaker motion signal and two different auxiliary functions at two ends of the signal. By testing a series of focusing waves in a physical wave tank, we found that with given wave energy, the QCWA spectrum can produce a focusing wave with larger crest elevation and farther focusing location from the wavemaker flap, as compared with the QCWS spectrum. However, both spectra lead to larger focusing wave crests when the wave frequency bandwidth was narrowed down and a positive correlation between the generated relative wave crest elevation and the input wave elevation parameter. The two spectra produce different focusing wave positions for the same wave frequency range. We also found that the focusing time strongly relates to the energy of the highest-frequency wave component of the wave spectrum.

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