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This study investigates the visual angle threshold value for the recognition of Chinese characters displayed on the optical head-mounted display. As optical head-mounted displays are becoming increasingly popular in various fields, character legibility has become an important topic for research. In this study, a legibility test was conducted by randomly displaying characters on the optical head-mounted display. The characteristics that were tested included the number of strokes, components and usage frequency rankings. The visual angle threshold value of each character was recorded and analysed. The results indicate that Chinese characters with more strokes, more components and lower usage frequency have a larger visual angle threshold value than characters with fewer strokes, fewer components and higher frequency. The number of strokes and usage frequency rankings were inputted into a regression model to predict the visual angle threshold value for character recognition (R2 = 0.72; Adj-R2 = 0.71). The regression analyses revealed that the foregoing inputs increased the visual angle threshold value. These findings provide a practical reference for the display of Chinese characters on optical head-mounted displays. [ABSTRACT FROM AUTHOR]

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The present study introduces a novel approach for quantifying distances within constructed environments. A mathematical model was developed for distance estimation in image processing using width and height estimation. In order to determine distance, the study employed the use of visual angle and sky view factor (SVF). Additionally, a camera with capabilities similar to the human eye was utilized to capture 360-degree photographs from a fixed position within a virtual reality corridor. The technique of Sky View Factor (SVF) is employed in indoor environments with ceilings by eliminating windows, doors, and roofs, thereby simulating a virtual sky. This enables the calculation of various parameters such as the image's area, area fraction, and aspect ratio through the utilization of image processing methods. Distance estimation can be predicted through the utilization of the sky view factor and visual angle, employing a linear regression analysis. The method of virtual sky view factor (VSVF) has potential applications in the fields of Engineering, robotics, and architecture for the estimation of indoor distances. [ABSTRACT FROM AUTHOR]

Visual working memory (VWM) is a cognitive mechanism essential for interacting with the environment and accomplishing ongoing tasks, as it allows fast processing of visual inputs at the expense of the amount of information that can be stored. A better understanding of its functioning would be beneficial to research fields such as simulation and training in immersive Virtual Reality or information visualization and computer graphics. The current work focuses on the design and implementation of a paradigm for evaluating VWM in immersive visualization and of a novel image-based computational model for mimicking the human behavioral data of VWM. We evaluated the VWM at the variation of four conditions: set size, spatial layout, visual angle (VA) subtending stimuli presentation space, and observation time. We adopted a full factorial design and analysed participants' performances in the change detection experiment. The analysis of hit rates and false alarm rates confirms the existence of a limit of VWM capacity of around 7 ± 2 items, as found in the literature based on the use of 2D videos and images. Only VA and observation time influence performances (p<0.0001). Indeed, with VA enlargement, participants need more time to have a complete overview of the presented stimuli. Moreover, we show that our model has a high level of agreement with the human data, r>0.88 (p<0.05). [ABSTRACT FROM AUTHOR]

In the light of the visual angle model (VAM), an improved car-following model considering driver’s visual angle, anticipated time and stabilizing driving behavior is proposed so as to investigate how the driver’s behavior factors affect the stability of the traffic flow. Based on the model, linear stability analysis is performed together with bifurcation analysis, whose corresponding stability condition is highly fit to the results of the linear analysis. Furthermore, the time-dependent Ginzburgâ€"Landau (TDGL) equation and the modified Kortewegâ€"de Vries (mKdV) equation are derived by nonlinear analysis, and we obtain the relationship of the two equations through the comparison. Finally, parameter calibration and numerical simulation are conducted to verify the validity of the theoretical analysis, whose results are highly consistent with the theoretical analysis. [ABSTRACT FROM AUTHOR]

Introduction: Culture in the architecture of any society is the representation of ideologies that are manifested in objective dimensions, which are formed in this process of architectural transformation. Architectural culture includes any building that materializes the mental thought of its designer through its appearance. Today, the pleasantness of the visual space is an important and significant issue in the field of architecture. While experimental and normative criteria have always been used to design building facades; But the subject of videoecology seeks to obtain visual criteria for greater adaptation of the artificial environment to human vision mechanisms with the visual world. research methodology: This article has tried to arrive at a specific algorithm based on visual ecology from the perspective of the culture that governs the society, considering the characteristics of the human eye structure in relation to building views and the analysis of vertical visual angles; So that, along with other existing aesthetic and normative criteria, this space can be formed in a more harmonious and pleasant manner. This research has used the descriptive-phenomenological method in an inferential and interpretive reading approach, and the information and data related to the subject have been used from the analytical-comparative method in relation to visual angles. Then data alignment was used to achieve the aforementioned algorithm and finally the research findings were presented as a result and a conceptual model. Findings: This research shows that the human eye has the ability to recognize color at specific vertical angles from 40 degrees below the horizon to 30 degrees above it; Also, the optimal range of eye rotation is 30 degrees below the horizon line to 25 degrees above it, and the maximum permissible range for humans is 70 degrees below the horizon line to 50 degrees above it. Conclusion: The results of this research on 4 landmark buildings showed that as in the Iranian architectural culture, respecting the human scale and people-friendly spaces has been considered, the height obtained from the algorithm [Maximum height = average human height + The distance between the observer and the building x tan a)] was one of the most common and pleasant heights used by designers in the architectural culture of their time. [ABSTRACT FROM AUTHOR]

We deal with integrals of invariant measures of pairs of planes in the Euclidean space E 3 as considered by Hug and Schneider. In this paper, we express some of these integrals in terms of functions of the visual angle of a convex set. As a consequence of our results, we evaluate the deficit in a Crofton-type inequality due to Blaschke. [ABSTRACT FROM AUTHOR]

Pedestrian re-identification searches for specific pedestrians in different environments, which has attracted widespread attention from domestic and foreign scholars in recent years. At present, pedestrian re-recognition algorithms mostly use a combination of local features and global features, and the training test on a single data set has achieved very good results. However, the results in the cross-domain test are not satisfactory, and the generalization ability is low. This paper proposes a cross-domain pedestrian re-recognition method based on deep capsule network. Through the view angle classification training task, the model can learn the effective features of the pedestrian in the image, and these features can be directly transferred to the pedestrian re-recognition task, alleviating the problem of insufficient generalization ability of pedestrian re-recognition. Experimental results show that this model is superior to all current pedestrian re-recognition methods based on unsupervised learning and has good generalization ability. [ABSTRACT FROM AUTHOR]

There are significant differences in the processing of perceived visuo-spatial information by drivers, which reflects their velocity optimization and collision avoidance abilities in car-following behavior. In addition, visuo-spatial working memory provides the driver with the functions of spatial information storage and attention allocation, which is critical in driving decision-making. Therefore, we try to use the data of car-following experiments in real traffic scenes to study the association between driving behavior and driver's visuo-spatial working memory and establish a new visual angle model based on data correlation analysis and dynamic characteristics. The effects of newly introduced attention allocation, visuo-spatial working memory duration, memory sensitivity to visuo-spatial rate of change, and vehicle size factors on the nonlinear and linear stability of traffic flow were analyzed. The above conclusions are verified by small disturbance simulation experiments. Finally, we propose a new collision assessment indicator incorporating visuo-spatial working memory and use it to conduct simulation experiments and statistical analysis on the improvement of the new model in driving safety. • A visual angle model incorporating visuo-spatial working memory was established. • The linear and nonlinear stability of the newly developed model are researched. • The influence of newly factors on the stability of traffic flow is simulated. • Collision risk is assessed by a newly developed traffic conflict indicator. [ABSTRACT FROM AUTHOR]

Convex polygons are distinguishable among the piecewise C ∞ convex domains by comparing their visual angle functions on any surrounding circle. This is a consequence of our main result, that every segment in a C ∞ multicurve can be reconstructed from the masking function of the multicurve given on any surrounding circle. [ABSTRACT FROM AUTHOR]

In this paper we deal with a general type of integral formulas of the visual angle, among them those of Crofton, Hurwitz and Masotti, from the point of view of Integral Geometry. The purpose is twofold: to provide an interpretation of these formulas in terms of integrals of functions with respect to the canonical density in the space of pairs of lines and to give new simpler proofs of them. [ABSTRACT FROM AUTHOR]

When we see another person’s gaze, spatial attention shifts toward the gaze direction. Thus, a gaze perceiver can more quickly respond to a forthcoming target when it appears in a direction of a gaze giver than when it does not. This phenomenon is termed the gaze cuing effect. Previous studies have investigated the gaze cuing effect only in foveal vision; hence, it remains unclear whether the gaze cuing effect is induced when a face is presented in peripheral vision. This is an important issue because in our daily lives we communicate not only with people in front of us but also with those in our periphery. To tackle this question, we manipulated vertically aligned locations of a facial stimulus (i.e., a face stimulus appeared above or below the center fixation) and tested the extent to which a gaze cuing effect, conveyed by gaze shifts of another, is observed in the periphery. The facial stimulus was located 0, ±2.5, ±5.0, and ±7.5° of the visual angle from the center of the display, and a target was presented 5.6° to the left or right of the center of the display. In Experiment 1, when participants responded to the location of an abrupt onset of a target (i.e., localization task), we observed significant gaze cuing effects when a facial stimulus was located 0, ±2.5, and ±5.0°, but not ±7.5°. In Experiment 2, we replicated the findings in Experiment 1 if participants pressed a key only when a target appeared (i.e., detection task). In Experiment 3, we used adjusted sizes of facial images based on the cortical representations and manipulated eye directions of the facial images oriented toward the possible target locations; it resulted in enlarged effective field of view for gaze cuing effects. The study reveals that gaze cuing effects can appear even in peripheral vision and within a vertical distance of 5.0° of the visual angles, but the effective field of view is expanded when the facial image is adjusted based on the cortical representations, and eye gaze directly looks at the possible target locations.

An illusory exaggeration of the horizon moon's visual angle (together with an apparently larger physical size) may account for its dramatic appearance. [ABSTRACT FROM AUTHOR]

When we see another person's gaze, spatial attention shifts toward the gaze direction. Thus, a gaze perceiver can more quickly respond to a forthcoming target when it appears in a direction of a gaze giver than when it does not. This phenomenon is termed the gaze cuing effect. Previous studies have investigated the gaze cuing effect only in foveal vision; hence, it remains unclear whether the gaze cuing effect is induced when a face is presented in peripheral vision. This is an important issue because in our daily lives we communicate not only with people in front of us but also with those in our periphery. To tackle this question, we manipulated vertically aligned locations of a facial stimulus (i.e., a face stimulus appeared above or below the center fixation) and tested the extent to which a gaze cuing effect, conveyed by gaze shifts of another, is observed in the periphery. The facial stimulus was located 0, ±2.5, ±5.0, and ±7.5° of the visual angle from the center of the display, and a target was presented 5.6° to the left or right of the center of the display. In Experiment 1, when participants responded to the location of an abrupt onset of a target (i.e., localization task), we observed significant gaze cuing effects when a facial stimulus was located 0, ±2.5, and ±5.0°, but not ±7.5°. In Experiment 2, we replicated the findings in Experiment 1 if participants pressed a key only when a target appeared (i.e., detection task). In Experiment 3, we used adjusted sizes of facial images based on the cortical representations and manipulated eye directions of the facial images oriented toward the possible target locations; it resulted in enlarged effective field of view for gaze cuing effects. The study reveals that gaze cuing effects can appear even in peripheral vision and within a vertical distance of 5.0° of the visual angles, but the effective field of view is expanded when the facial image is adjusted based on the cortical representations, and eye gaze directly looks at the possible target locations. [ABSTRACT FROM AUTHOR]

Given a simple closed plane curve Γ of length L enclosing a compact convex set K of area F , Hurwitz found an upper bound for the isoperimetric deficit, namely L 2 − 4 π F ≤ π | F e | , where F e is the algebraic area enclosed by the evolute of Γ. In this note we improve this inequality finding strictly positive lower bounds for the deficit π | F e | − Δ , where Δ = L 2 − 4 π F . These bounds involve either the visual angle of Γ or the pedal curve associated to K with respect to the Steiner point of K or the L 2 distance between K and the Steiner disk of K . For compact convex sets of constant width Hurwitz's inequality can be improved to L 2 − 4 π F ≤ 4 9 π | F e | . In this case we also get strictly positive lower bounds for the deficit 4 9 π | F e | − Δ . For each established inequality we study when equality holds. This occurs for those compact convex sets being bounded by a curve parallel to an hypocycloid of 3, 4 or 5 cusps or the Minkowski sum of this kind of sets. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to find whether the visual evoked potential (VEP) latencies and amplitude are altered with different visual angles in healthy adult volunteers or not and to determine the visual angle which is the optimum and most appropriate among a wide range of check sizes for the reliable interpretation of pattern reversal VEPs (PRVEPs). Materials and Methods: The present study was conducted on 40 healthy volunteers. The subjects were divided into two groups. One group consisted of 20 individuals (nine males and 11 females) in the age range of 25-57 years and they were exposed to checks subtending a visual angle of 90, 120, and 180 minutes of arc. Another group comprised of 20 individuals (10 males and 10 females) in the age range of 36-60 years and they were subjected to checks subtending a visual angle of 15, 30, and 120 minutes of arc. The stimulus configuration comprised of the transient pattern reversal method in which a black and white checker board is generated (full field) on a VEP Monitor by an Evoked Potential Recorder (RMS EMG. EPMARK II). The statistical analysis was done by One Way Analysis of Variance (ANOVA) using EPI INFO 6. Results: In Group I, the maximum (max.) P100 latency of 98.8 ± 4.7 and the max. P100 amplitude of 10.05 ± 3.1 μV was obtained with checks of 90 minutes. In Group II, the max. P100 latency of 105.19 ± 4.75 msec as well as the max. P100 amplitude of 8.23 ± 3.30 μV was obtained with 15 minutes. The min. P100 latency in both the groups was obtained with checks of 120 minutes while the min. P100 amplitude was obtained with 180 minutes. A statistically significant difference was derived between means of P100 latency for 15 and 30 minutes with reference to its value for 120 minutes and between the mean value of P100 amplitude for 120 minutes and that of 90 and 180 minutes. Conclusion: Altering the size of stimulus (visual angle) has an effect on the PRVEP parameters. Our study found that the 120 is the appropriate (and optimal) check size that can be used for accurate interpretation of PRVEPs. This will help in better assessment of the optic nerve function and integrity of anterior visual pathways.

AIM: To introduce a new color pediatric visual acuity chart and its clinical application.METHODS:The color pediatric visual acuity chart was designed based on principle of visual angle. The optotype on the color chart had graphics. The progression rate of optotype size between 2 lines was 10(10)1/2 and 1.2589. A regular geometric progression of optotype sizes and distribution was employed to arrange 8 lines with 11 optotype on the color chart. The testing distance was 3m. The visual acuity score could be recorded as logarithm of the minimum angle of resolution notation or decimal notation. The reliability of naked distant measurements with this new chart was tested in one eye of 100 children(4 ～6 years old)taking the Chinese national standard logarithm visual acuity chart standard. RESULTS: The color pediatric visual acuity chart and logarithmic chart controls, visual acuity test results that in the two groups had no significant difference(t=1.2671, P>0.05). Two sets of vision data existed positive correlation(r=0.924, PCONCLUSION:Children are easier to accept used new color pediatric visual acuity chart to inspect vision. New chart is reliability and apply to children's vision screening.