Wyniki wyszukiwania - BazTech

1

Ach, te moje oczy zmęczone... Jak sobie radzić z objawami astenopii i ZSO w XXI wieku

Błoch W., Seredyka-Burduk M., Stępniewski P.

Optyka

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2018

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Nr 2

62--64

2

Development of a practical high frequency brain–computer interface based on steady-state visual evoked potentials using a single channel of EEG

Ajami S., Mahnam A., Abootalebi V.

Biocybernetics and Biomedical Engineering

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2018

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Vol. 38, no. 1

106--114

EN

Brain–computer interfaces based on steady-state visual evoked potentials have recently gained increasing attention due to high performance and minimal user training. Stimulus frequencies in the range of 4–60 Hz have been used in these systems. However, eye fatigue when looking at low-frequency flickering lights, higher risk of induced epileptic seizure for medium-frequency flickers, and low signal amplitude for high-frequency flickers complicate appropriate selection of flickering frequencies. Here, different flicker frequencies were evaluated for development of a brain–computer interface speller that ensures user's comfort as well as the system's efficiency. A frequency detection algorithm was also proposed based on Least Absolute Shrinkage and Selection Operator estimate that provides excellent accuracy using only a single channel of EEG. After evaluation of the SSVEP responses in the range of 6–60 Hz, three stimulus frequency sets of 30–35, 35–40 and 40–45 Hz were adopted and the system's performance and corresponding eye fatigue were compared. While the accuracy of the asynchronous speller for all three stimulus frequency sets was close to the maximum (average 97.6%), repeated measures ANOVA demonstrated that the typing speed for 30–35 Hz (8.09 char/min) and 35–40 Hz (8.33 char/min) are not significantly different, but are significantly higher than for 40–45 Hz (6.28 char/min). On the other hand, the average eye fatigue scale for 35–40 Hz (80%) is comparable to that for 40–45 Hz (85%), but very higher than for 30–35 Hz (60%). Therefore, 35–40 Hz range was proposed for the system which resulted in 99.2% accuracy and 67.1 bit/min information transfer rate.

3

Stereoscopic image visual perception

Fornalczyk K., Napieralski P., Szajerman D., Wojciechowski A.

International Journal of Microelectronics and Computer Science

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2015

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Vol. 6, nr 1

15--22

EN

Stereoscopic films and interactive presentations are extensively popularized whereas their perceived quality still dissatisfies viewers. The reasons are shared between hardware inconsistencies and stereo image producers unawareness concerning factors influencing depth perception quality. This paper reviews aspects influencing 3D image perception visual comfort, presents visual comfort estimation methods and suggests how to measure image perception quality. It also comprises results of researches conducted on dedicated CinemaVision Movie Diagnostics work stand.

4

Wyniki badań zmęczenia wzroku osób o umiarkowanym upośledzeniu widzenia w zależności od systemu oświetleniowego

Pawlak A.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 3a

88-91

PL

W artykule przedstawiono wyniki badań eksperymentalnych mających na celu ustalenie preferencji oświetleniowych osób o umiarkowanym upośledzeniu widzenia. Omówiono przebieg tych badań oraz opracowano metodę oceny zmęczenia wzroku, która składała się z badań obiektywnych oraz subiektywnych. Zaprezentowano także opracowany system oświetleniowy, który był w badaniach alternatywą dla opraw oświetlenia ogólnego z rastrami parabolicznymi.

EN

The paper presents the results of experimental investigation aimed at the assessment of lighting preferences of workers with moderately poor sight. Conduction of research was described, as well as, the method of assessment of eye fatigue, that consists of objective and subjective studies. The author presents the designed of lighting system that was the alternative for general lighting with parabolic louver during the research.

5

Inteligentne systemy sterowania oświetleniem a zmęczenie wzroku użytkowników

Wolska A.

Przegląd Elektrotechniczny

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2007

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R. 83, nr 5

97-99

PL

Jedną z podstawowych cech inteligentnych systemów sterowania oświetleniem jest utrzymywanie stałego poziomu natężenia oświetlenia będącego sumą światła dziennego oraz elektrycznego. Celem badań było określenie zmęczenia wzroku i samopoczucia pracowników biurowych obsługujących komputer przy różnych systemach oświetlenia zarządzanych przez cyfrowy system sterowania oświetleniem (DALI). Badania wykonane były w warunkach laboratoryjnych dla trzech systemów oświetleniowych.

EN

One of the main features of new intelligent lighting control systems is to maintain the desired level of illuminance from the mixture of daylight and artificial lighting. The purpose of the study was to define visual fatigue and well-being of VDT operators under an automatic operation of digital light control system (DALI). Experiments were carried out in laboratory conditions for three different lighting systems which ensured compliance with lighting requirements and created different luminous environments.

6

Visual Strain and Lighting Preferences of VDT Users Under Different Lighting Systems

Wolska A.

International Journal of Occupational Safety and Ergonomics

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2003

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Vol. 9, No. 4

431--440

EN

Lighting influences users’ visual strain and well-being. Therefore creating lighting that ensures visual work conditions do not results in visual fatigue is a preventive activity. The aim of the study was to model different lighting systems for visual display terminal (VDT) work and to determine their influence on users’ visual strain and preferences. The results of the study showed that visual fatigue was lowest for indirect and compound lighting systems. On the other hand, in general, direct lighting realized by “dark-light” luminaires was the most preferred lighting system. Some interesting differences related to age, gender, and VDT work experience were found. On the basis of the obtained results lighting designers can be provided with some guidance.

7

Luminance of the Surround and Visual Fatigue of VDT Operators

Wolska A., Swituta M.

International Journal of Occupational Safety and Ergonomics

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1999

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Vol. 5, No. 4

553--580

EN

Luminance distribution in the visual field is considered as one of causal factors with a significant influence on visual fatigue, especially for intensive and extended Video Display Terminal (VDT) work. The aim of the study was to define visual fatigue of VDT operators for different values of surrounding luminance. Experiments were carried out in laboratory conditions under 3 lighting conditions. Only 1 lighting parameter - the luminance of the wall behind the display (surrounding luminance) - changed. Visual fatigue was measured both by a subjective evaluation of different visual complaints (asthenopic symptoms) and by objective measurements of changes in the following visual functions: accommodation, convergence, habitual horizontal phoria, critical fusional frequency (CFF), and visual acuity. The same experiments were done for CRT (Cathode Ray Tube) and LCD TFT (Liquid Crystal Display with Thin Film Transistor) screens. The results of the study have shown that there was no significant influence of the value of surrounding luminance on the asthenopic symptoms for either type of screen. A general tendency towards bigger visual complaints for LCD TFT than for CRT participants was found. An objective evaluation of visual fatigue demonstrated a tendency towards bigger changes in visual functions with an increase of surrounding luminance for both screens. Statistical analysis of the results has shown that surrounding luminance influences significantly the reduction of the accommodation amplitude (significance level < .05).