Screen Refresh Rate Research Articles

Sistem pendukung keputusan pemilihan smartphone tahun 2022 menggunakan metode simple additive weighting berbasis MATLAB

This research develops a decision support system using the Simple Additive Weighting (SAW) method based on MATLAB to choose a smartphone in 2022. Based on the specified criteria and data, the best smartphone that managed to get the highest rating is the Xiaomi Redmi Note 12 Pro. This smartphone meets the criteria for price, rating, 5G features, NFC, IR Blaster, RAM capacity, internal memory, battery, screen refresh rate, and rear main camera well. This decision support system provides effective assistance in choosing a smartphone according to user preferences and needs.

Применение технологии SDR (Software Defined Radio) для восстановления сигналов побочных электромагнитных излучений видеотракта

This article presents the results of recovering signals of spurious electromagnetic radiation of a video path using an SDR receiver. This work demonstrates the existence of a potential risk of leakage of confidential information through a technical channel of information leakage due to spurious electromagnetic radiation of a video path, bypassing traditional cryptographic and physical methods of information protection. An attack can be carried out by an attacker without special technical knowledge and special professional expensive equipment. The presented stand makes it possible to simplify research related to spurious electromagnetic radiation, as well as to apply this technology to build a learning process in this domain. In the course of the work, a description of the concept of a technical channel of information leakage and a brief description of the side electromagnetic radiation of the video path are given. The following briefly describes the SDR technology, the selected USRP B210 receiver, and the cross-platform open source GNU Radio software package. The demonstration stand is described in detail and the results of image reconstruction are given. In addition, two stages of the development of a demonstration stand are considered: using a simulation signal and a real intercepted signal. A demonstration stand with simulation signals serves to develop a user's understanding of the properties of spurious electromagnetic radiation, as well as possible obstacles to converting an intercepted signal into an image. The studies of the real intercepted signal were carried out on a monitor with a set resolution of 1280×1024 and a screen refresh rate of 60 Hz. An analog VGA (Video Graphics Array) interface was used to connect the monitor. The dependence of the quality of the reconstructed image on the set sampling frequency of the SDR receiver is shown.

Decision Support System for Laptop Selection Using AHP Method and Profile Matching

Laptop is a desktop personal computer (PC) whose dimensions are reduced to increase flexibility in its use. However, the large number of products will make it difficult for consumers to choose a laptop that suits the needs of consumers who want to buy it.The purpose of this research is to help buyers who want to buy laptop products according to their needs by making a Decision Support System (DSS). There are 12 criteria considered in this research, price, processor, RAM capacity, hard disk capacity, SSD capacity, V-RAM capacity, maximum RAM upgrade capacity, laptop weight, screen size, screen type, screen refresh rate, and screen resolution. Choosing a laptop product there is a criterion value of a laptop product and a value of preference criteria from the buyer as a decision maker. Also the criteria values on laptop products have different contributions to the overall value of the laptop product. Thus, the methods used are Analytical Hierarchy Process (AHP), Profile Matching (PM) with linear interpolation, and Simple Addictive Weighting (SAW) to determine the recommended options. Lastly, SPK that has been made will be able to provide recommendations best alternative choices and best suit the needs of buyers for selecting laptop products.

Individual Differences in Subconscious Motor Control Predicted by GABA Concentration in SMA

Subliminal visual stimuli affect motor planning, but the size of such effects differs greatly between individuals. Here, we investigated whether such variation may be related to neurochemical differences between people. Cortical responsiveness is expected to be lower under the influence of more of the main inhibitory neurotransmitter, GABA. Thus, we hypothesized that, if an individual has more GABA in the supplementary motor area (SMA)--a region previously associated with automatic motor control--this would result in smaller subliminal effects. We measured the reversed masked prime--or negative compatibility--effect, and found that it correlated strongly with GABA concentration, measured with magnetic resonance spectroscopy. This occurred specifically in the SMA region, and not in other regions from which spectroscopy measurements were taken. We replicated these results in an independent cohort: more GABA in the SMA region is reliably associated with smaller effect size. These findings suggest that, across individuals, the responsiveness of subconscious motor mechanisms is related to GABA concentration in the SMA.

Predictors of Tool Usage in the Military Health System's Electronic Health Record, the Armed Forces Health Longitudinal Technology Application

To assess the association between key predictor variables and use of advanced features for the Armed Forces Health Longitudinal Technology Application (AHLTA), the electronic health record (EHR) for the Military Health System (MHS). Secondary analysis of a web-based volunteer survey of 520 Navy AHLTA users. chi2 and logistic regression methods were used to assess the strength of relationship between three predictor variables and the use of several advanced AHLTA features. Adequacy of initial training was associated with increased use of the template management module (adjusted OR = 2.34, 95% CI 1.64-3.61) and order sets (adjusted OR = 1.64, 95% CI 1.07-2.51). Duration of AHLTA usage was associated with use of all advanced features (adjusted OR = 1.69-6.12, p < or = 0.001-0.045). Physicians use most of the advanced features more than nonphysicians (adjusted OR = 1.95-7.07, p < or = 0.001-0.030). Seventy percent of users cited a slow screen refresh rate as a problem. Training, duration of usage, and provider role are associated with use of advanced features.

Visual Flicker in the Gamma-Band Range Does Not Draw Attention

External transients, such as a flash or a startling sound, are believed to capture attention. Bauer, Cheadle, Parton, Müller, and Usher reported that attention can also be captured by a stimulus that flickers subliminally at 50 Hz, presumably by entrainment of neurons to the flicker frequency. In their reaction time (RT) task, participants had to locate a subtle change in the spatial frequency content of one of three Gabors (the target). Prior to target onset, presumably subliminal 50-Hz flicker in one of the Gabors served as a spatial cue. Bauer et al. found faster RTs when the cued location was congruent with the target location than when the cue was incongruent with the target location. In their experiments, the cue stopped to flicker at 50 Hz at target onset and was replaced by a stimulus flickering at 100 Hz (i.e., the screen refresh rate). In the present study, we show that the transition from 50 to 100 Hz results in a flash-like impression that can be localized above chance. We suggest that the illusory transition flash interfered with the localization of the subtle target, which contributed to the congruency effect. In support of this view, participants selected the flickering object more often than the non-flickering object when they failed to respond to the target. Further, no cueing effects were observed when the cue continued to flicker until the end of the trial or when the target was a salient change in polarity. In our view, the cueing effect occurs because observers confuse the illusory transition flash with the target when the two are similar. When truly subliminal flicker is used (70-Hz flicker), very small cueing effects persist in the absence of an illusory transition flash but may be accounted for by small effects on reaction time unrelated to attention.

Contrast sensitivity to angular frequency gratings is not higher than to Cartesian gratings.

When contrast sensitivity functions to Cartesian and angular gratings were compared in previous studies the peak sensitivity to angular stimuli was reported to be 0.21 log units higher. In experiments carried out to repeat this result, we used the same two-alternative forced-choice paradigm, but improved experimental control and precision by increasing contrast resolution from 8 to 12 bits, increasing the screen refresh rate from 30 Hz interlaced to 85 Hz non-interlaced, linearizing the voltage-luminance relation, modulating luminance in frequencies that minimize pixel aliasing, and improving control of the subject's exposure to the stimuli. The contrast sensitivity functions to Cartesian and angular gratings were similar in form and peak sensitivity (2.4 cycles per visual degree (c/deg) and 32 c/360 degrees, respectively) to those reported in a previous study (3 c/deg and 32 c/360 degrees, respectively), but peak sensitivity to angular stimuli was 0.13 log units lower than that to Cartesian stimuli. When the experiment was repeated, this time simulating the experimental control level used in the previous study, no difference between the peak sensitivity to Cartesian and angular stimuli was found. This result agrees with most current models that assume Cartesian filtering at the first visual processing stage. The discrepancy in the results is explained in part by differences in the degree of experimental control.

The effects of intermittent illumination on a visual inspection task.

Two experiments are described in which eye movements were monitored as subjects performed a simple target-spotting task under conditions of intermittent illumination produced by varying the display-screen frame rate on a computer VDU. In Experiment 1, subjects executed a saccade from a fixation point to a target which appeared randomly at a fixed eccentricity of 14 character positions to the left or right. Saccade latency did not differ reliably as a function of screen refresh rate, but average saccade extent at 70 Hz and 110 Hz was reliably shorter than at 90 Hz and 100 Hz. Experiment 2 examined the same task using a range of target eccentricities (7, 14, and 28 character positions to the left and right) and across a wider range of screen refresh rates. The results confirmed the curvilinear relationship obtained in Experiment 1, with average saccade extent reliably shorter at refresh rates of 50 Hz and 125 Hz than at 75 Hz and 100 Hz. While the effect was greater for remote targets, analyses of the proportional target error failed to show a reliable interaction between target eccentricity and display refresh rate. In contrast to Experiment 1, there was a pronounced effect of refresh rate on saccade latency (corrected for time to write the screen frame), with shorter latencies at higher refresh rates. It may be concluded that pulsation at frequencies above fusion disrupts saccade control. However, the curvilinear functional relationship between screen refresh rate and saccade extent obtained in these studies differs from previously reported effects of intermittent illumination on the average size of "entry saccades" (the first saccade to enter a given word) in a task involving word identification (Kennedy & Murray, 1993a, 1996). This conflict of data may arise in part because within-word adjustments in viewing position, which are typical of normal reading, influence measures of average saccade extent.

High refresh rate and oculomotor adaptation facilitate reading from video displays

Reading from a video display terminal (VDT) was tested at screen refresh rates of 500 Hz and 60 Hz. Reading was initially 8 words/min (3.05%) faster at 500 Hz. A hypothesis that reading rate on VDTs is limited by stimulus availability accounts for the difference. When the eye reaches a new fixation position, it 'parks' until a sample of text appears at the fovea. Then processing resumes in the normal way. This idea, combined with the 500-Hz reading data, can predict reading rate at any refresh rate, and is quantitatively confirmed by the reading rate at 60 Hz. The difference in reading rates disappeared for the second half of the text, as a result of differences between frequencies of eye movements in the two refresh conditions. From the first half to the second, subjects at 60 Hz made more large forward saccades and fewer small reverse saccades. Both changes make sampling of the text more sparse, compensating for the dead time between samples. Subjects were unaware of refresh conditions, differences in their reading rates, and types of eye movements they generated. Reading from a continuously illuminated active-matrix display is slightly faster than from a comparable VDT.

Eye Movement Control During the Inspection of Words Under Conditions of Pulsating Illumination

Previous work has suggested that eye movement control in reading is disturbed by pulsating illumination such as that characteristic of visual display units, which are periodically refreshed. The average size of the first saccade directed towards a word (the ''entry saccade'') varies as a function of screen refresh rate. We report the results of an experiment which attempted to discern whether this arises through a direct effect of pulsation on saccade control or as a result of a strategic adaptation to phenomenal image degradation which might be associated with refreshed displays. Subjects examined a prompt word followed by two target words. Depending on the prompt, a decision was required as to whether the two target words were physically identical or had the same meaning. The task was conducted in four conditions of screen pulsation (50, 75, 100 and 125 Hz) and in both positive (i.e. black-on-white) and negative (white-on-black) polarity. Since launch position into the first target word was tightly cont...

The Relation between Target Localisation in Strings of Letters, Contrast, and Refresh Rate

Jacobs (1987, Vision Research27 1953 – 1966) obtained psychometric curves to investigate the relationship between target localisability and the latency of primary saccades. These psychometric curves show correct scores as a function of string length, target location, and target-background similarity. They were obtained with white text on a black background. We repeated this experiment, with a few extensions. First, we did not only use white text on a black background, but we used black text on a white background as well. The stimuli were also presented with the use of isoluminant colours. Second, we varied the refresh rate of the screen (from 60 Hz up to 150 Hz). Third, we used two different instructions for the subjects: in one the subject was instructed to indicate the position of the target relative to the beginning of the string; in the other the position of the target relative to the fixation point. When the string was presented to the right of the fixation point, the results of these two instructions were predicted to be similar; in the other case the results might be different. The results of our experiments show a clear effect of the amount of contrast between text and background, and an influence of the screen refresh rate. We also found that the results differ depending on the instruction used. Sadly, we were not able to replicate all of the results of the original experiment by Jacobs.

The Effects of Screen Refresh Rate on Editing Operations Using a Computer Mouse Pointing Device

Two experiments are described in which subjects attempted to locate a specified target word in a short text using a cursor controlled by a computer mouse pointing device. The task was performed at screen refresh rates of 50 Hz, 75 Hz, and 100 Hz. In Experiment 1, both the timing and accuracy of the cursor movement was influenced by screen pulsation. During the early phase of the movement, performance was worse at 100 Hz, whereas in the later, visually guided phase, performance was worse at 50 Hz. In Experiment 2, eye movements were recorded as the task was performed. The results show that the cursor movement is typically preceded by an eye movement and that subjects do not directly inspect the cursor in the early stages of its movement. In the later phase of the movement the cursor is tracked for considerable periods of time. The data suggest that adverse effects of screen pulsation on the control of cursor movement are inherited from penalties incurred during the process of target computation but may also be influenced by concurrent eye movements.