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The interest in the field of immersive audio/visual systems exists for many years from both of the commercialization point of view and the research perspective. Technological advancements in the field of cameras, video display along with the processing hardware lead the way to a new generation of immersive systems. On one hand, advancement in video compression schemes like MPEG and H.264/AVC, and transmission technologies like and 3G and 4G LTE enhanced the feeling of virtual presence. However, on the other hand the secure transmission of immersive audio/visual contents over wireless networks is a challenge, as it suffers from the potential malicious attacks. One type of typical malicious attack is passive eavesdropping. The goal of this paper is to propose a solution to enhance the secure wireless transmissions of Video in Immersive Systems via simple yet effective physical-layer approach. To reduce the chance that that the passive eavesdropper extracts information, we present a physical-layer security method, termed noise aggregation, for the secure video transmission to legitimate receiver. Theoretical analyses and simulation results demonstrate that our method is able to effectively limit the amount of information eavesdropped by the unauthorized user at bit level, and thus significantly enhancing security for video distribution. [ABSTRACT FROM AUTHOR]

This study investigated the effects of font size, stroke width, and character complexity on the legibility of Chinese characters. A within-subjects design experiment was employed. Thirty-six subjects participated in the experiment and completed the character-search tasks in the pseudo-texts. The search time per target character, correct response number, and correct response rate were used to measure the legibility. The results indicated that the font size and character complexity had significant effects on the legibility, while the effect of stroke width was not significant. All the two-way interactions among the three display factors had significant effects on the legibility. Stroke width is critical to the legibility for characters with high-level complexity, whereas font size is the critical factor influencing the legibility for characters with low-level complexity. The combination of 12pt font size and 1:10 stroke width resulted in the best legibility for both character complexity levels. The findings provide useful information for the font design of Chinese texts displayed on a visual display terminal to improve the legibility. [ABSTRACT FROM AUTHOR]

The human-machine interaction interface design between users and cloud is an important problem in Cloud manufacturing research system. The subjective evaluation on a visual display terminal (VDT) interface is usually influenced by the subject's emotional or mental factors, which will lead to the inaccurate results. In this paper, an objective description model was established by least square method on the basis of the combination of subjective and objective experiments. The test objects were the instrument interfaces with different color combinations. The amplitude and latency of P100 and P300 induced by different combinations were obtained, as well as the occupancy of electroencephalogram (EEG) power under different bands. Besides, a subjective evaluation was performed. Through correlation analysis, the highly relevant relationships were found among the visual comfort (VC) and P300 amplitude at the parietal lobe (P4) F ( r = 0.644, p < 0.05), the occupancy of β band power P ( r = 0.85, p < 0.005), and the rate of β/(α + θ) P ( r = −0.872, p < 0.005). Through the least square surface fitting, a mathematical model of visual comfort (VC) was established and F and P are independent variables. The model reveals that the relationship between VC and FP4 is positive linear and the relationship between VC and P is quadratic parabola; a negative relation is found between VC and the interaction of F and P. The above results illustrated that it is feasible to use this model to evaluate the visual comfort objectively. It can provide support for all kinds of personalized customization of the user interface in the whole life cycle of cloud manufacturing. [ABSTRACT FROM AUTHOR]

Electronic visual displays have shown a rapid technological evolution in the last two decades. With reference to the ergonomic requirements for video display terminal (VDT) workstations (ISO 9241), at an international level, attention is focused on the human–system interaction. With reference to visual ergonomics, the aim of this study is to assess luminance conditions through in-field measurements in order to evaluate: luminance and contrast ratios, luminance and contrast non-uniformities. The assessment was applied to widespread flat screen displays and repeated for fourteen combinations of Contrast–Brightness. The analysis carried out by the Authors shows the importance of realizing a simple and quick procedure to determine the performance levels of displays used in VDT workstations. The proposed assessment could be used as a practical tool for staff assigned to assess the risks arising from VDT use in the workplace within the Occupational Health and Safety Assessment Procedure. [ABSTRACT FROM AUTHOR]

Background: Computer vision syndrome (CVS) is a group of visual symptoms experienced in relation to the use of computers. Nearly 60 million people suffer from CVS globally, resulting in reduced productivity at work and reduced quality of life of the computer worker. The present study aims to describe the prevalence of CVS and its associated factors among a nationally-representative sample of Sri Lankan computer workers. Methods: Two thousand five hundred computer office workers were invited for the study from all nine provinces of Sri Lanka between May and December 2009. A self-administered questionnaire was used to collect socio-demographic data, symptoms of CVS and its associated factors. A binary logistic regression analysis was performed in all patients with 'presence of CVS' as the dichotomous dependent variable and age, gender, duration of occupation, daily computer usage, pre-existing eye disease, not using a visual display terminal (VDT) filter, adjusting brightness of screen, use of contact lenses, angle of gaze and ergonomic practices knowledge as the continuous/dichotomous independent variables. A similar binary logistic regression analysis was performed in all patients with 'severity of CVS' as the dichotomous dependent variable and other continuous/dichotomous independent variables. Results: Sample size was 2210 (response rate—88.4 %). Mean age was 30.8 ± 8.1 years and 50.8 % of the sample were males. The 1-year prevalence of CVS in the study population was 67.4 %. Female gender (OR: 1.28), duration of occupation (OR: 1.07), daily computer usage (1.10), pre-existing eye disease (OR: 4.49), not using a VDT filter (OR: 1.02), use of contact lenses (OR: 3.21) and ergonomics practices knowledge (OR: 1.24) all were associated with significantly presence of CVS. The duration of occupation (OR: 1.04) and presence of pre-existing eye disease (OR: 1.54) were significantly associated with the presence of 'severe CVS'. Conclusions: Sri Lankan computer workers had a high prevalence of CVS. Female gender, longer duration of occupation, higher daily computer usage, pre-existing eye disease, not using a VDT filter, use of contact lenses and higher ergonomics practices knowledge all were associated with significantly with the presence of CVS. The factors associated with the severity of CVS were the duration of occupation and presence of pre-existing eye disease. [ABSTRACT FROM AUTHOR]

As surgeons, we have spent years training to excel in a variety of settings: technical masters in the operating room, well-honed clinicians in the wards and clinic, able to function efficiently despite sleep deprivation and without regular meals or breaks. In one survey study, [[5]] of 104 surgeons who sustained a musculoskeletal injury at work, 49% required medical treatment but only 19% of these injuries were reported by the surgeon to their institution. Upper extremity stretches: trapezius stretch, levator scapulae stretch, cross-body shoulder stretch. [Extracted from the article]

Purpose To evaluate the validity of a dry eye (DE) screening method in visual display terminal (VDT) workers using functional visual acuity (VA) measurement combined with a symptoms questionnaire, and to make recommendations regarding practical use of the screening. Methods This prospective cross-sectional study included 369 young and middle-age office workers, who use VDTs. Subjects completed two types of DE questionnaires and underwent DE testing and functional VA measurement. Subjects were assigned to DE and non-DE groups. Sensitivity and specificity of the DE prediction value were assessed. According to the probability distribution of DE and non-DE calculated by the discriminant analysis formula, we classified subjects into three categories based on the most appropriate cut-off levels. Positive predictive value (PPV) and negative predictive value (NPV) of the DE prediction value were also assessed. Results Of 369 subjects, 218 and 151 subjects were assigned to the DE and non-DE groups, respectively. Sensitivity and specificity were 93.1% and 43.7%, respectively. Based on the probability prediction, the cutoff levels were defined as probability prediction ≥85%, 45%≤ probability prediction <85% and probability prediction <45%. Subjects with a probability prediction ≥85% were defined positive (N=130), while those with values <45% were defined as negative (N=73). The PPV and NPV were 83.8% and 80.8%, respectively. Conclusions Acceptable PPV and NPV were obtained by setting three discriminate categories. This improved version of the DE screening method may be acceptable for practical use in VDT workers. [ABSTRACT FROM AUTHOR]

With the ever-growing number of people who work at visual display terminals, the work-related musculoskeletal disorders of the upper body are believed to be an important problem all over the world. The forearm support, which can keep the forearm and wrist in biomechanical posture, is a possible protective factor of the development of upper body syndrome. This meta-analysis examines the efficacy of forearm support in reducing upper body syndrome. The Cochrane Library, EMBASE, Ovid, ScienceDirect, SpringerLink, Google Scholar, CNKI database, and Wanfang database were searched from inception until May 29, 2013. Relevant studies were included after the screening of title, abstract, and the full text. Impact of bias was assessed independently by 2 authors. Four studies that met all the inclusion criteria were included finally. The combined results based on all studies suggested that statistically the forearm support had a nonsignificant effect on upper body syndrome (odds ratio [OR] = 0.70, 95% confidence interval [CI]: 0.49, 1.02). The result of subgroup analysis suggested that forearm support has a significant effect on neck or shoulder syndrome (OR = 0.70, 95% CI: 0.43, 1.14) and the effect on upper extremity syndrome (OR = 0.76, 95% CI: 0.49, 1.19) is not significant. This meta-analysis suggested that the forearm support had statistically nonsignificant effect on preventing upper body syndrome on the whole. [ABSTRACT FROM PUBLISHER]

In this paper, participants operated visual display terminals (VDT); the authors analyzed their pulse wave signals to develop objective indices for diagnosing and assessing VDT-induced. The experiment used 30 healthy undergraduates test subjects; each subject operated static PC for 4 hours. The pulse waves of local blood volumes in the test subjects' finger-tips were measured every 30 minutes for 2 minutes. After the experiment, the pulse wave parameters were analyzed. All test subjects exhibited signs of visual fatigue according to the fatigue scale results. There were significant differences of heart rate (HR), which clearly declined before and after the experiment (P<0.01). The indexes RMSSD, SDNN, P3, P4, P5, P6, and TP had significant differences (P<0.01) and all rose. The positions of the main and dicrotic waves advanced (P<0.01). The experiment parameters prompted significant changes; pulse wave forms changed during VDT work. Based on these results, pulse wave analysis holds promise as an effective, noninvasive technique for measuring VDT fatigue. [ABSTRACT FROM AUTHOR]

In Latvia occupational musculoskeletal disorder - chronic neck-shoulders pain (NSP) - is a common complaint in the general population, also in video display terminal (VDT) employees in their giving age, working in bank and agriculture system, and such patients with chronic NSP load markedly the public health care service. The biopsychosocial influence on pain for VDT employees is team learning (TL) with self-management (SM) strategies: pain-blocking imagery, mind-body relaxation, cognitive restructuring of unpleasant physical and emotional experience, improvement of workplace relations and organizational culture. The aim of the research was to evaluate the effectiveness of using TL and SM one month course for bank and agricultural advisory services VDT employees, females and males, suffering from chronic moderate NSP. The structured self-administrated questionnaire was carried out to find out which body parts suffer from pain during workload, information on work-related ergonomic and psychosocial risk factors was collected during face to face interviews. During testing for TL and SM course with follow-up assessment was selected 21 VDT employees (females = 11, males = 10; age between 22 and 50). The intensity of NSP was determined by using the Numeric Pain Rating Scale (NPRS), life quality assessment was analysed with Quality of Life Scale (QOLS), p-value, confidence interval was calculated. Patients were asked to keep a Pain Diary during treatment course. The results indicated decrease in neck-shoulders pain intensity, and positive quality of life changes after TL and SM intervention in video display terminal (VDT) employees. Statistically significant reduction in pain intensity after TL and SM intervention by the biopsychosocial influence on pain according NPRS was among males, and the life quality according to QOLS score - among females. The necessity to perform patient's objective clinical examinations, subjective tests of self-esteem, to keep a Pain Diary during treatment course has been proved in our research. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the relationship between subjective symptoms and clinical signs in dry eye disease (DED) in office workers using visual display terminals (VDTs). DESIGN: Cross-sectional study. METHODS: This study involved 672 Japanese young and middle-aged office workers who use VDTs. The subjects completed questionnaires designed to detect subjective symptoms and risk factors for DED. Dry eye tests, including tear film break-up time (TBUT), cornealconjunctival staining with fluorescein and lissamine green, and the Schirmer test, were performed. Based on the Japanese diagnostic criteria for DED, the subjects were classified into 3 groups: definite DED, probable DED, and non-DED. Between each group, subjective symptoms and clinical signs were compared. RESULTS: Of the 672 subjects, 561 (374 male, 187 female) completed the questionnaire (response rate: 83.5%). Definite DED was diagnosed in 65 subjects (11.6%), probable DED in 303 subjects (54.0%), and non-DED in 193 subjects (34.4%). The mean subjective symptom score was significantly less in subjects with probable DED (2.05 ± 0.42) and non-DED (1.63 ± 0.38) than in those with definite DED (2.19 ± 0.40) (P < .05 and P < .01, respectively). In the subjects with probable DED, a subgroup with positive subjective symptoms and abnormal TBUT (≤5 seconds) was categorized as short TBUT-type DED, and it was found that they had a higher subjective symptom score (2.09 ± 0.40), equivalent to that of those with definite DED (P = .269). CONCLUSIONS: Despite no or minor epithelial damage, the severity of subjective symptoms was greater in short TBUT-type DED, most likely attributable to tear film instability. Thus, it might prove important to evaluate TBUT to successfully treat those patients. [ABSTRACT FROM AUTHOR]

Multiple human detection and tracking is a very important and active research topic in computer vision. At present, the recognition performance is not satisfactory, which is mainly due to the fact that the full-body of human cannot be captured efficiently by cameras. In this paper, an improved method is developed to detect and track multiple heads by considering them as rigid body parts. The appearance model of human heads is updated according to fusion of color histogram and oriented gradients. An associative mechanism of detection and tracking has been developed to recover transient missed detections and suppress transient false detections. The object identity can be kept invariant during tracking even if unavoidable occlusion occurs. Besides, the proposed method is fast to detect and track multiple human in a dynamic scene without any hypothesis for the scenario contents in advance. Comparisons with state-of-the-arts have indicated the superiority and good performance of the proposed method. [ABSTRACT FROM AUTHOR]

Purpose: Extended screen time amongst youth is a pervasive global phenomenon, with wide-ranging implications for health and quality of life. Dry eye disease is increasingly reported as emerging in paediatric populations and is associated with modified blinking behaviour during extended screen time. This study sought to evaluate spontaneous blink rates, dry eye symptomology and screen use habits of young extended screen time users.Methods: Attendees of a gaming convention in Auckland, NZ, completed a self-directed iPad-based survey on personal screen use habits and ocular symptoms using the 5-item Dry Eye Questionnaire (DEQ-5) and the Symptom Assessment in Dry Eye (SANDE) questionnaire. Blink rate was covertly and concomitantly recorded using the front-facing iPad camera and quantified by automated software. A validated, self-assessment blink test was administered as a proxy for tear film stability measurements.Results: A total of 456 respondents (mean age ± SD: 24 ± 10 years, range: 13 - 75, 38% female) reported an average weekly screen time of 43.7 ± 24.4 h. DEQ-5 and SANDE scores were 10 ± 3 and 34 ± 19; 90% of respondents qualified as symptomatic for dry eye disease (DEQ-5 ≥ 6). Blink test results suggested a tear film stability < 10 s in 24% of cases. Poorer symptomology correlated with increased screen use, elevated blink rates and reduced proxy tear film stability (r = 0.15 to 0.22, all p < 0.01).Conclusion: Extended screen time in a young population was associated with blinking behaviour and symptomology consistent with patients with dry eye. Implementing routine clinical screening, educational interventions, and developing official guidance on safe screen use may help prevent an accelerated degradation of ocular surface health and quality of life in young people. [ABSTRACT FROM AUTHOR]

This research proposes an assessment model for quantifying the perceived visual complexity (PVC) of an in-vehicle instrument cluster. An initial study was conducted to investigate the possibility of evaluating the PVC of an in-vehicle instrument cluster by estimating and analyzing the complexity of its individual components. However, this approach was only partially successful, because it did not take into account the combination of the different components with random levels of complexity to form one visual display. Therefore, a second study was conducted focusing on the effect of combining the different components. The results from the overall research enabled us to suggest a basis for quantifying the PVC of an in-vehicle instrument cluster based both on the PVCs of its components and on the integration effect. [ABSTRACT FROM AUTHOR]

Introduction: IT has revolutionized economies throughout the world, more so in India. West Bengal has also got its share of IT boom. But with this, it has brought in the class of human resource of Video Display Terminal workers operators that and along with that can cause a host of occupational problems in them namely musculoskeletal, ocular and psychological systems. The current study had assessed some of the musculoskeletal disorders occurring due to VIDEO DISPLAY TERMINAL use. Materials and Methods: An analytical cross-sectional study was done in a Software Company of Sector V, Kolkata, the IT hub of West Bengal. Of all the employees, required sample size of 206 was selected by Simple Random Sampling. After proper permissions and consent, socio-demographic variables were collected by standardized instruments, musculoskeletal morbidity was collected by Nordic questionnaire, and ergonomic practices were obtained by checklists. Results: 90.78% of population showed some form of musculo skeletal symptoms. They were highest in fingers, elbows, wrist, shoulder, upper, while legs and lower back showed low morbidities. Increasing age, female sex, increasing years of work, repetition of work, poorer ergonomic scores all showed to have increased the symptoms. The regionwise ergonomic scores revealed how the poorer scores affected the musculo skeletal systems adversely. Several individual adverse ergonomic practices were also elicited. Discussion: The study goes hand to hand with many other studies throughout the world and also in India. However, a much higher morbidity has been found in this study probably due to a symptom based questionnaire. The adverse practices obtained here goes well with other relevant studies. Conclusion: This study puts occupational health problems of VIDEO DISPLAY TERMINAL users, and upholds the need of future multicentric cohort studies along with implementation of proper measures to ameliorate the effects of this occupational hazard. [ABSTRACT FROM AUTHOR]

Purpose: A study was designed to evaluate the efficacy of three different strategies aiming at increasing spontaneous eyeblink rate (SEBR) during computer use. Methods: A total of 12 subjects (5 female) with a mean age of 28.7 years were instructed to read a text presented on a computer display terminal during 15 min. Four reading sessions (reference and three "blinking events" [BE]) were programmed in which SEBR was digitally recorded. "Blinking events" were based on either a slight distortion of the text characters or on the presentation of a white screen instead of the text, with or without accompanying blinking instructions. All BE had a duration of 20 ms and occurred every 15 s. Participants graded the intrusiveness of each BE configuration, and the number of lines participants read in each session was recorded. Results: Data from 11 subjects was analysed. A statistically significant difference in SEBR was encountered between the experimental configuration consisting on a white screen plus blinking instructions (7.8 blinks/min) and both reference (5.2 blinks/min; p = 0.049) and white screen without blinking instructions (4.8 blinks/min; p = 0.038). All three BE had superior levels of intrusiveness than reference conditions, although the performance of participants (line count) was not compromised. Conclusions: The joint contribution of white screen and blinking instructions has been shown to result in a short term improvement in blinking rate in the present sample of non-dry eye computer users. Further work is necessary to improve the acceptance of any BE aiming at influencing SEBR. [ABSTRACT FROM AUTHOR]

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Purpose/Aim: Wink glass (WG), an invention to stimulate blinking at interval of 5 s was designed to reduce dry eye symptoms during visual display unit (VDU) use. The objective of this study is to investigate the effect of WG on visual functions that include blink rate, ocular surface symptoms (OSS) and tear stability during VDU use. Materials and methods: A total of 26 young and asymptomatic subjects were instructed to read articles in Malay language with a computer for 20 min with WG whereby their blink rate, pre- and post-task tear break-up time, and OSS were recorded. The results were compared to another reading session of the subjects wearing a transparent plastic sheet as a control. Results: Non-invasive tear break-up time was reduced after reading session with transparent plastic sheet (pre-task = 5.97 s, post-task = 5.14 s, z = −2.426, p = 0.015, Wilcoxon), but remained stable (pre-task = 5.62 s, post-task = 5.35 s, z = −0.67, p = 0.501) during the reading session with WG. The blink rate recorded during reading session with plastic sheet was 9 blinks/min (median) and this increased to 15 blinks/min (z = −3.315, p = 0.001) with WG. The reading task caused OSS (maximum scores = 20) with median score of 1 (0-8) reduced to median score of 0 (0-3) after wearing WG (z = −2.417, p = 0.016). Conclusion: WG was found to increase post-task tear stability, increased blinking rate and reduced OSS during video display unit use among young and healthy adults. Although it may be considered as an option to improve dry eye symptoms among VDU users, further studies are warranted to establish its stability and its effect on subjects with dry eyes. [ABSTRACT FROM AUTHOR]

The monitoring of molecular systems usually requires sophisticated technologies to interpret nanoscale events into electronic-decipherable signals. We demonstrate a new method for obtaining read-outs of molecular states that uses graphics processing units made from molecular circuits. Because they are made from molecules, the units are able to directly interact with molecular systems. We developed deoxyribozyme-based graphics processing units able to monitor nucleic acids and output alphanumerical read-outs via a fluorescent display. Using this design we created a molecular 7-segment display, a molecular calculator able to add and multiply small numbers, and a molecular automaton able to diagnose Ebola and Marburg virus sequences. These molecular graphics processing units provide insight for the construction of autonomous biosensing devices, and are essential components for the development of molecular computing platforms devoid of electronics. [ABSTRACT FROM AUTHOR]

Objective: To explore meibomian gland dysfunction (MGD) may determine the severity of dry eye conditions in visual display terminal (VDT) workers. Methodology: Prospective, case-control study carried out in China.106 eyes of 53 patients (VDT work time >4 hour per day) were recruited as the Long time VDT group; 80 eyes of 40 control subjects (VDT work time ≤4 hour per day) served as the Short time VDT group. A questionnaire of Ocular Surface Disease Index (OSDI) and multiple tests were performed. Three dry eye tests: tear film breakup time (BUT), corneal fluorescein staining, Schirmer I test; and three MGD parameters: lid margin abnormality score, meibum expression assessment (meibum score), and meibomian gland dropout degree (meiboscore) using Keratograph 5 M. Principal Findings: OSDI and corneal fluorescein score were significantly higher while BUT was dramatically shorter in the long time VDT group than the short time VDT group. However, the average of Schirmer tear volumes was in normal ranges in both groups. Interestingly, the three MGD parameters were significantly higher in the long time VDT group than the short time one (P<0.0001). When 52 eyes with Schirmer <10 mm and 54 eyes with Schirmer ≥10 mm were separated from the long time VDT workers, no significant differences were found between the two subgroups in OSDI, fluorescein staining and BUT, as well as the three MGD parameters. All three MGD parameters were positively correlated with VDT working time (P<0.0001) and fluorescein scores (P<0.0001), inversely correlated with BUT (P<0.05), but not correlated with Schirmer tear volumes in the VDT workers. Conclusions: Our findings suggest that a malfunction of meibomian glands is associated with dry eye patients in long term VDT workers with higher OSDI scores whereas some of those patients presenting a normal tear volume. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the effectiveness of providing interruption recovery assistance in the form of an interactive visual timeline of historical events on a peripheral display in support of team supervision in time-critical settings. As interruptions can have detrimental effects on task performance, particularly in time-critical work environments, there is growing interest in the design of tools to assist people in resuming their pre-interruption activity. A user study was conducted to evaluate the use of an interactive event timeline that provides assistance to human supervisors in time-critical settings. The study was conducted in an experimental platform that emulated a team of operators and a mission commander performing a time-critical unmanned aerial vehicle (UAV) mission. The study results showed that providing interruption assistance enabled people to recover from interruptions faster and more accurately. These results have implications for interface design that could be adopted in similar time-critical environments such as air-traffic control, process control, and first responders. [Copyright &y& Elsevier]

In this paper, we propose a luminance and color correction scheme for multiview image compression for a 3-DTV system. According to characteristics of luminance and chrominance, we propose a 3-D discrete cosine transform (3-D DCT) for 3-D image compression. Then, a cubic memory-based 3-D DCT is proposed for 3-D image compression in this paper. 3-D display technology has become an important technology lately. TFT-based multiview 3-D display has the advantage of convenient setup, mass production, and a large amount of 3-D content support, making it a popular 3-D display product. However, multiview 3-D signals need huge storage space and wide channel bandwidth, especially when view number is larger than two views. To overcome the obstacles, we propose a 3-D DCT component based on cubic memory to perform 3-D image compression in this paper. The presented architecture reduces a great quantity of memory space and provides efficient 3-D signal storage. [ABSTRACT FROM PUBLISHER]

Background: Along with the rapid growth of technology its related tools such as computer, monitors and video display terminals (VDTs) grow as well. Based on the studies, the most common complaint reported is of the VDT users. Methods: This study attempts to design a proper tool to assess the visual fatigue of the VDT users. First draft of the questionnaire was prepared after a thorough study on the books, papers and similar questionnaires. The validity and reliability of the questionnaire was confirmed using the content validity index (CVI) beside that of the Cronbach's Coefficient Alpha. Then, a cross-sectional study was carried out on 248 of the VDT users in different professions. A theoretical model with four categories of symptoms of visual fatigue was derived from the previous studies and questionnaires. Having used the AMOS16 software, the construct validity of the questionnaire was evaluated using the confirmatory factor analysis. The correlation co-efficiency of the internal domains was calculated using the SPSS 11.5 software. To assess the quality check index and determining the visual fatigue levels, visual fatigue of the VDT users was measured by the questionnaire and visual fatigue meter (VFM) device. Cut-off points were identified by receiver operating characteristic curves. Results: CVI and reliability co-efficiency were both equal to 0.75. Model fit indices including root mean of squared error approximation, goodness of fit index and adjusted goodness of fit index were obtained 0.026, 0.96 and 0.92 respectfully. The correlation between the results measured with the questionnaire and VFM-90.1 device was -0.87. Cut-off points of the questionnaire were 0.65, 2.36 and 3.88. The confirmed questionnaire consists of four main areas: Eye strain (4 questions), visual impairment (5 questions) and the surface impairment of the eye (3 questions) and the out of eye problems (3 questions). Conclusions: The visual fatigue questionnaire contains 15 questions and has a very remarkable validity and reliability. Using this questionnaire and its findings, one will be able to identify, assess and finally prevent the effective factors of VDT users' visual fatigue. [ABSTRACT FROM AUTHOR]

Principal axis methods such as principal component analysis (PCA) and correspondence analysis (CA) are useful for identifying structures in data through interesting planar graphic displays. However, some kinds of data sets can be dealt alternatively with PCA or CA. This paper focuses on methods, such as PCA and CA, and on visual displays. Our aim is to illustrate the implications for a potential user of selecting either method, and its advantages and disadvantages, from an applied point of view. This is a matter covered broadly in textbooks and elsewhere considering theoretical arguments. Our purpose is to contribute to the comparison between these methods, over the same data set, in order to illustrate them for the practitioner. In the first part of this paper we present a novel analytical study of a binary matrix associated with a non-oriented axis-symmetric graph and show that CA outperforms standardized PCA for the reconstitution and visualization of such kind of graphs. In the second part we present a case using real data dealing with the distribution of employees in different economic sectors for the countries of the European Union, analyzed by means of standardized PCA and two-way CA, in order to see the differences between the two methods in practice. [ABSTRACT FROM AUTHOR]

Our eyes are increasingly exposed to light from the emitting diode (LED) light of video display terminals (VDT) which contain much blue light. VDTs are equipped with televisions, personal computers, and smart phones. The present study aims to clarify the mechanism underlying blue LED light-induced photoreceptor cell damage. Murine cone photoreceptor-derived cells (661 W) were exposed to blue, white, or green LED light (0.38 mW/cm2). In the present study, blue LED light increased reactive oxygen species (ROS) production, altered the protein expression level, induced the aggregation of short-wavelength opsins (S-opsin), resulting in severe cell damage. While, blue LED light damaged the primary retinal cells and the damage was photoreceptor specific. N-Acetylcysteine (NAC), an antioxidant, protected against the cellular damage induced by blue LED light. Overall, the LED light induced cell damage was wavelength-, but not energy-dependent and may cause more severe retinal photoreceptor cell damage than the other LED light. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes our research in full-surround, multimodal, multi-user, immersive instrument design in a large VR instrument. The three-story instrument, designed for large-scale, multimodal representation of complex and potentially high-dimensional information, specifically focuses on multi-user participation by facilitating interdisciplinary teams of co-located researchers in exploring complex information through interactive visual and aural displays in a full-surround, immersive environment. We recently achieved several milestones in the instrument's design that improves multi-user participation when exploring complex data representations and scientific simulations. These milestones include affordances for “ensemble-style” interaction allowing groups of participants to see, hear, and explore data as a team using our multi-user tracking and interaction systems; separate visual display modes for rectangular legacy content and for seamless surround-view stereoscopic projection using 4 high-resolution, high-lumen projectors with hardware warping and blending integrated with 22 small-footprint projectors placed above and below the instrument's walkway; and a 3D spatial audio system enabling a variety of sound spatialization techniques. These facilities can be accessed and controlled by a multimodal framework for authoring applications integrating visual, audio, and interactive elements. We report on the achieved instrument design. [Copyright &y& Elsevier]

An approach is described for monitoring urine samples using a portable system based on chromatic techniques and for predicting urinary tract infection (UTI) from the results. The system uses a webcam–computer combination with the screen of a computer visual display unit as a tuneable illumination source. It is shown that the system can operate in a robust manner under ambient lighting conditions and with potential for use as a point of care test in primary care. The present approach combines information on urine liquid concentration and turbidity. Its performance in an exploratory study is compared with microbiological culture of 200 urine samples, of which 79 had bacterial growth >105 colony forming unit/millilitre (cfu ml−1) indicative of UTI. It is shown that both sensitivity and negative predictive value of 0.92 could be achieved. [ABSTRACT FROM AUTHOR]

The investigation light-emitting diode (LED) dimming temporal response when used in large scale LED video displays is presented. The aim was to find the response times for several driver topologies. Four driver topologies were considered: commercial constant current driver, passive driver, transconductance amplifier and constant current driver with tamper turn-off. 85 red Screen Master LEDs from Cotco were used in experiments. Measurement setup and circuit diagrams of the equipment used are presented. Measurement results for rise and fall fronts measurement are reported. Investigation results indicate that circuits possessing fast constant current drive (passive driver, transconductance amplifier and constant current driver with tamper turn-off) have similar performance for the front where this constant current source is operational: rise time. Average rise time for the aforementioned topologies is 62 ns, 54 ns and 56 ns accordingly. It was concluded, that average rise time is 283 ns and fall time was 111 ns when commercial driver MBI5026 was used. This is in high contrast with manufacturer specifications. Tamper turn-off produced very short fall time (4.2 ns) but this created large skew in light output response therefore it can be predicted that dimming linearity performance will be the worst. If passive driver is used then rise and fall response are 62 ns and 30 ns correspondingly. Lowest skew was obtained for transconductance amplifier-based topology. [ABSTRACT FROM AUTHOR]

Background: To validate the association between accommodation and visual asthenopia by measuring objective accommodative amplitude with the Optical Quality Analysis System (OQAS®, Visiometrics, Terrassa, Spain), and to investigate associations among accommodation, ocular surface instability, and visual asthenopia while viewing 3D displays. Methods: Fifteen normal adults without any ocular disease or surgical history watched the same 3D and 2D displays for 30 minutes. Accommodative ability, ocular protection index (OPI), and total ocular symptom scores were evaluated before and after viewing the 3D and 2D displays. Accommodative ability was evaluated by the near point of accommodation (NPA) and OQAS to ensure reliability. The OPI was calculated by dividing the tear breakup time (TBUT) by the interblink interval (IBI). The changes in accommodative ability, OPI, and total ocular symptom scores after viewing 3D and 2D displays were evaluated. Results: Accommodative ability evaluated by NPA and OQAS, OPI, and total ocular symptom scores changed significantly after 3D viewing (p = 0.005, 0.003, 0.006, and 0.003, respectively), but yielded no difference after 2D viewing. The objective measurement by OQAS verified the decrease of accommodative ability while viewing 3D displays. The change of NPA, OPI, and total ocular symptom scores after 3D viewing had a significant correlation (p < 0.05), implying direct associations among these factors. Conclusions: The decrease of accommodative ability after 3D viewing was validated by both subjective and objective methods in our study. Further, the deterioration of accommodative ability and ocular surface stability may be causative factors of visual asthenopia in individuals viewing 3D displays. [ABSTRACT FROM AUTHOR]