Emergent dynamics of the Kuramoto ensemble under the effect of inertia

We study the emergent collective behaviors for an ensemble of identical Kuramoto oscillators under the effect of inertia. In the absence of inertial effects, it is well known that the generic initial Kuramoto ensemble relaxes to the phase-locked states asymptotically (emergence of complete synchronization) in a large coupling regime. Similarly, even for the presence of inertial effects, similar collective behaviors are observed numerically for generic initial configurations in a large coupling strength regime. However, this phenomenon has not been verified analytically in full generality yet, although there are several partial results in some restricted set of initial configurations. In this paper, we present several improved complete synchronization estimates for the Kuramoto ensemble with inertia in two frameworks for a finite system. Our improved frameworks describe the emergence of phase-locked states and its structure. Additionally, we show that as the number of oscillators tends to infinity, the Kuramoto ensemble with infinite size can be approximated by the corresponding kinetic mean-field model uniformly in time. Moreover, we also establish the global existence of measure-valued solutions for the Kuramoto equation and its large-time asymptotics

Discomfort luminance level of head-mounted displays depending on the adapting luminance

The Images in an immersive head-mounted display (HMD) for virtual reality provide the sole source for visual adaptation. Thus, significant, near-instantaneous increases in luminance while viewing an HMD can result in visual discomfort. Therefore, the current study investigated the luminance change necessary to induce this discomfort. Based on the psychophysical experiment data collected from 10 subjects, a prediction model was derived using four complex images and one neutral image, with four to six levels of average scene luminance. Result showed that maximum area luminance has a significant correlation with the discomfort luminance level than average, median, or maximum pixel luminance. According to the prediction model, the discomfort luminance level of a head-mounted display was represented as a positive linear function in log(10) units using the previous adaptation luminance when luminance is calculated as maximum area luminance

The Monster is Growing

Panel: America Abroa

Analysis of different class sizes on decision making processes and teaching behaviors of highly experienced teachers (HETs) and less experienced teachers (LETs)

Objectives. This study examined the decision making process employed by two highly experienced teachers (HETs) and two less experienced teachers (LETS) as they planned for and taught lessons with two different class sizes; n=15-16 and n=30-31. A secondary purpose of this study was to investigate the influence of class size on teaching behaviors and student learning. Finally, this study used in-depth interviews to describe concerns associated with teaching and preparing lessons for classes of different size.;Design and setting. This was a mixed-methods study that utilized both behavioral analysis and qualitative methods of investigation. Qualitative methods included think-aloud, stimulated-recall techniques and semi-structured, open-ended interviews which were used to describe participants teaching concerns when dealing with class size. Quantitative methods included the use of the West Virginia University Teaching Evaluation System (WVUTES; Hawkins & Wiegand, 1989), and Field System Analysis (FSA; Sharpe & Hawkins, 1992) which were used to examine the influence of class size on teaching and student learning behaviors.;Subjects. Two highly experienced physical education teachers (HET1 and HET2) and two less experienced physical education teachers (LET1 and LET2, student teachers) were involved in this study. Pseudonyms were used for all participants in this study including: Erick Sam (HET1), Erin Hong (HET2), Nancy Young (LET1) and Nathan Smith (LET2). A total of 184 student participants were recruited from the two different elementary schools along with their cooperating physical education teachers.;Results. WVUTES data showed that HETs used similar instructional behaviors in terms of the amount, duration and frequency of feedback given during both classes. FSA revealed that all teachers provided individual feedback more often in smaller classes. Experienced teachers provided more individual feedback in larger classes, whereas their less experienced counterparts provided individual feedback more frequently only in smaller classes.;Conclusions. Smaller classes are more beneficial especially for less experienced teachers, due to the increase in frequency of individual feedback. Class size was an important consideration for planning, specifically selecting content and the organizational structure. Experienced teachers used multiple formations to deal with variations in class size. Less experienced teachers tend to use the one teaching format (either station or cohort) they were most comfortable with for both classes regardless of size. In this study, station teaching: (1) allowed students to concentrate better on instructional tasks; (2) reduced managerial tasks; (3) aided in the prevention off-task behaviors. Another critical component was the frequency of individual feedback, which kept students more active and engaged in class activities. Smaller class sizes appear more beneficial especially for less experienced teachers, due to the increase in the delivery of individual feedback