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Background: According to the findings of several studies conducted on work-related musculoskeletal disorders (WMSDs) among the video display terminals (VDTs) users, Prevention of these disorders among this population is a challenge for many workplaces today. Ergonomically Improving of VDT workstations may be an effective and applicable way to decrease the risk of WMSDs. This study evaluated the effect of an ergonomics-training program on the risk of WMSDs among VDT users. Methods: This study was conducted among a large group of computer users in SAPCO industrial company, Tehran, Iran (84 persons with 29.85±11.2 years of age and with 6.98±2.54 years of experience). An active ergonomics-training program was designed and implemented during 14 days to empower the VDT users and involve them in improving their workstations. The direct observational RULA (Rapid Upper Limb Assessment) method was used in pre and post-intervention stages to evaluate the risk of WMSDs among participants. Results: The RULA final scores showed that 18.8 % of VDT users were at action level 2, 63.5% at action level 3 and 17.6% at action level 4 before any intervention. In addition, 8.2% of users were at action level 1, 44.7% at action level 2, 42.4% at action level 3 and 4.7% at action level 4 at the post-intervention stage. The results of Wilcoxon statistical test indicated that RULA scores ere decreased significantly after interventions (P < 0.05) and consequently, decreased risk of WMSDs. Conclusion: Active ergonomics training programs can be used effectively to improve the VDT workstations and decrease the risk of musculoskeletal disorders among VDT users. [ABSTRACT FROM AUTHOR]

Background: Musculoskeletal pains are the main health problems reported by computer workers. There has been an increased frequency of ergonomic injuries and illness in the computer workstation. The increase in Visual Display Terminal (VDT) use has been associated with an increased prevalence of disorders in the neck, upper extremities and lower back of the body. Furthermore, poor workstation design has been associated with an increased risk of developing these symptoms. Aims: To estimate the prevalence of musculoskeletal disorders among visual display terminal (VDT) users. Method: A cross-sectional study was conducted over a two month period during the summer of 2010 in Baquba. One hundred twenty VDT workers are selected randomly comprising 60 male and 60 female. Questionnaire was performed among these VDT workers for study period to measure the prevalence during the previous 12 months of musculoskeletal disorders. The survey was carried out on the effect of work with VDTs on musculoskeletal disorders in workers in the computer workstation. Results: The result of this study was that the neck, shoulder and lower back problem are the main problems among VDT workers. Both male and female VDT workers also suffered pain in neck, shoulder, low back, forearm, wrist, elbow and the different parts of the upper extremities. This study revealed that the female VDT workers suffer more discomfort feeling than male VDT workers. Prolonged period of work in an awkward posture mainly lead to discomfort feeling among the VDT workers. The 12 month prevalence of musculoskeletal complaints in various body parts were: neck (30.0%), back (28.3%), shoulder (18.3%), wrist (8.3%), forearm (6.6%) elbow (5.8%) and (2.5%) fingers. It was found that there was a gradual increase in musculoskeletal complaints as the number of hours spent for working on computers daily increased. Conclusions: It is concluded that; The VDT workers suffered pain mainly in neck, upper extremities and lower back of the body. As the duration of job increased, the risk for musculoskeletal symptoms significantly increased. Recommendation: More consideration should be paid to the ergonomics of workstations, the placing of the mouse, the postures of the upper extremities and the handling of the mouse. [ABSTRACT FROM AUTHOR]

Today, several vehicles are equipped with a visual display combined with a haptic rotary device for handling in-vehicle information system tasks while driving. This experimental study investigates whether a haptic addition to a visual interface interferes with or supports secondary task performance and whether haptic information could be used without taking eyes off road. Four interfaces were compared during simulated driving: visual only, partly corresponding visual-haptic, fully corresponding visual-haptic, and haptic only. Secondary task performance and subjective mental workload were measured. Additionally, the participants were interviewed. It was found that some haptic support improved performance. However, when more haptic information was used, the results diverged in terms of task completion time and interface comprehension. Some participants did not sense all haptics provided, some did not comprehend the correspondence between the haptic and visual interfaces, and some did. Interestingly, the participants managed to complete the tasks when using haptic-only information. [ABSTRACT FROM AUTHOR]

One of the more debated issues regarding training simulators is their validity for transfer of skills to sensory environments that differ from the simulator. In two experiments, the advantages of three-dimensional (3D) and collocated (Col) visual displays were evaluated in a realistic and complex visuomotor task. The two factors were evaluated independently, comparing Col-2D with dislocated-2D (experiment 1) and with Col-3D (experiment 2). As expected, in both cases the more immersive presentation condition facilitated better performance. Furthermore, improvement following training in the more immersive condition carried over to the following less immersive condition but there was no carry over in the opposing order of presentation. This is taken as an indication for the differential development of skills conditioned by the level of immersiveness of the training environment. This further suggests that learning of complex realistic tasks is not carried over from less immersive simulator to the complex sensory environment of reality, due to the large gap in sensory patterns. [ABSTRACT FROM AUTHOR]

As more and more technology is added to the automobile interior it needs to be designed in a usable and efficient way: to facilitate safe driving. This paper reviews guidelines and visual design principles for automotive instrumentation. Guidelines were compiled, categorized and analysed in order to determine whether they were valid and usable for today's design of information presentation in automobiles. By doing this, contradictory guidelines and gaps in knowledge were identified and discussed. However, there appeared a consensus within the different guidelines of best practice, and many are still usable by designers today. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the effect of moving from small offices to a landscape environment for 19 Visual Display Unit (VDU) operators at Alcatel Denmark AS. The operators reported significantly improved lighting condition and glare situation. Further, visual discomfort was also significantly reduced on a Visual Analogue Scale (VAS). There was no significant correlation between lighting condition and visual discomfort neither in the small offices nor in the office landscape. However, visual discomfort correlated significantly with glare in small offices i.e. more glare is related to more visual discomfort. This correlation disappeared after the lighting system in the office landscape had been improved. There was also a significant correlation between glare and itching of the eyes as well as blurred vision in the small offices, i.e. more glare more visual symptoms. Experience of pain was found to reduce the subjective assessment of work capacity during VDU tasks. There was a significant correlation between visual discomfort and reduced work capacity in small offices and in the office landscape. When moving from the small offices to the office landscape, there was a significant reduction in headache as well as back pain. No significant changes in pain intensity in the neck, shoulder, forearm, and wrist/hand were observed. The pain levels in different body areas were significantly correlated with subjective assessment of reduced work capacity in small offices and in the office landscape. By careful design and construction of an office landscape with regard to lighting and visual conditions, transfer from small offices may be acceptable from a visual-ergonomic point of view. [Copyright &y& Elsevier]

Abstract: Manmade electromagnetic (EM) field in the low frequency range of the spectrum, from static to 200kHz has caused interference with electronic equipment and poses a possible public health risk. Typical sources of these EM emissions include television sets, video display terminals (VDT), electric appliances, fluorescent lights, certain medical devices, walk-through and hand-held detectors, radio stations, induction heating, wireless electricity delivered over distance, hybrid cars and transmission lines. Our main goals for writing this paper are, first, to describe taking measurements of the frequencies and magnetic field levels in residential and occupational environments, particularly around cathode ray tube displays, induction heating units, and hybrid cars; and, second, to compare the measurements to the established or recommended limits according to national standards so that engineers and scientists can understand these nontrivial electrical measurements. The field measurements were carried out using different kinds of devices where a brief description of the instruments used is also provided. [Copyright &y& Elsevier]

This paper explores the effectiveness, efficiency and ease of use of two alternative interface interactions in a mobile tablet application. More specifically, the study employs a navigation task which novice users were required to complete by means of two types of main menu button, one utilizing text and the other utilizing a visual metaphor. Furthermore, little evidence exists on the effect of the use of metaphor on users of various ages and levels of computer experience. Our results show that young users prefer buttons that display a visual metaphor in the form of an icon, in contrast to older participants, who preferred the button that employed text. They also show that the users' performance is dependent upon age. [ABSTRACT FROM AUTHOR]

ABSTRACT Autonomous virtual characters (AVCs) are becoming more prevalent both for real-time interaction and also as digital actors in film and TV production. AVCs require believable virtual human animations, accompanied by natural attention generation, and thus the software that controls the AVCs needs to model when and how to interact with the objects and other characters that exist in the virtual environment. This paper models automatic attention behaviour using a saliency model that generates plausible targets for combined gaze and head motions. The model was compared with the default behaviour of the Second Life (SL) system in an object observation scenario while it was compared with real actors' behaviour in a conversation scenario. Results from a study run within the SL system demonstrate a promising attention model that is not just believable and realistic but also adaptable to varying task, without any prior knowledge of the virtual scene. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents a study on the prevalence of neck-upper extremity musculoskeletal disorders (MSD) among users of video display terminals (VDT). The researchers performed a comparative cross-sectional study on 95 Egyptian Telecommunications Co. employees at Mansoura from February 2006 to August 2007. They obtained anthropometric measurements for all subjects. They found no significant difference in the prevalence of neck-upper extremity MSD among VDT users compared to controls.

Braking systems in motor vehicles are important to preserve safety in traffic. They serve to effectively stop the vehicle in motion. This paper will present an innovative application of the classical concept of disc brake caliper and apply solutions to minimize high-frequency vibrations and raise the efficiency of the brake. Collected in an experimental way the data are preliminary information for further study and justify the applicability of utilitarian in the automotive industry. [ABSTRACT FROM AUTHOR]

hand-held 3D scanning technique is proposed to reconstruct 3D models of real objects. A sequence of range images captured from a hand-held stereo camera is automatically registered to a reference coordinate system. The automated scanning process consists of two states, coarse and fine registration. At the beginning, scanning process starts at the fine registration state. A fast and accurate registration refinement technique is used to align range images in a pair-wise manner. If the refinement technique fails, the process changes to the coarse registration state. A feature-based coarse registration technique is proposed to find correspondences between the last successful frame and the current frame. If the coarse registration successes, the process returns to the fine registration state again. A fast point-to-plane refinement technique is employed to do shape-based registration. After the shape-based alignment, a texture-based refinement technique matches texture features to enhance visual appearance of the reconstructed models. Through a graphic and video display, a human operator adjusts the pose of the camera to change the view of the next acquisition. Experimental results show that 3D models of real objects are reconstructed from sequences of range images. [ABSTRACT FROM AUTHOR]

The article presents a study on the effective points of view (POV) in occupational health management for visual display terminals (VDT) operators with disabilities. It is mentioned that for the validation of POV, two VDT operators with cerebral palsy were examined through observations of the equipment used and posture as well as measurement of sitting pressure distribution and surface electromyogram. The article also discusses solution of the problem and importance of POV in health management.

The paper presents a video monitoring system utilizing fixed and PTZ cameras for tracking of moving objects. First type of camera provides image for background modelling, being employed for foreground objects localization. Estimated objects locations are then utilised for steering of PTZ cameras when observing targeted objects with high close-ups. Objects are classified into several classes, then basic event detection is being performed. Event type, object localisation and images acquired by the cameras are presented visually in a "live map" system. In the paper details related to detection of moving objects are presented. Next, camera calibration procedure and geopositioning coordinates way of processing are discussed. Event detection is described. Finally an experiment is presented, organised in order to verify the camera tracking system accuracy. [ABSTRACT FROM AUTHOR]

Boundary and finite element modeling approach to the assessment of electrostatic field on human head generated by Video Display Units (VDU's) are compared and discussed. Attention is focused to the field distribution over the surface of the face. The mathematical formulation for the assessment of the electrostatic field is based on the Laplace equation for the electric scalar potential. The electrostatic field is calculated for two different models of face. Numerical results are presented and compared in order to estimate the accuracy and computational efficiency of the two methods for the considered problem. In order to make comparison as meaningful as possible, boundary and finite element codes have been both developed by the authors. In general, boundary element appears to be the better choice than finite element with respect to computational efficiency and level of accuracy. [ABSTRACT FROM AUTHOR]

Rail signalling in the UK has seen a move from mechanical lever frame boxes to entry and exit signalling, and on through to situating signallers within a visual display unit-based workstation environment. These developments have taken place in tandem with changes such as making the signallers more remote from their area of control and the introduction of automation. These changes have implications not only at a cognitive level for factors such as workload and situation awareness, but also at an organizational level, such as the shift away from traditional career progression, and the resulting implications for training and the development of expertise. Understanding the implications of the signalling interface and the design implementation of automation is critical in facilitating more effective performance, safety, and signaller well-being, as well as informing the design of future rail control systems. Bainbridge articulated a set of ironies of automation — unintended consequences of introducing automation that may not be beneficial to the overall system effectiveness. The work presented in this article uses a structured observation approach to examine behavioural indicators of the impact of automation, either as a successful tool to support signalling or as a source of some or all of the ironies noted by Bainbridge. The work was conducted over a period of 2 years, to investigate the effect of levels of automation on rail signallers’ activity and workload as part of the EPSRC Rail Research UK B6 programme. [ABSTRACT FROM AUTHOR]

For IEEE 802.11-based wireless local area networks (WLANs), due to inherent random access mechanisms, it is very challenging to provision video services, which are subject to very stringent quality-of-service (QoS) constraints. Collision and fading are two main sources of packet loss in WLANs and as such, both are affected by the packetization at the medium access control (MAC) layer. While a larger packet is preferred to balance protocol header overhead, a shorter packet is less vulnerable to packet loss due to channel fading errors or staggered collisions in the presence of hidden terminals. In this paper, we exploit estimate of collision probabilities to adapt packetization for video frames. We first show analytically that the effective throughput is a unimodal function of packet size when considering both channel fading and staggered collisions. We then design an additive increase and multiplicative decrease (AIMD) packetization strategy which adjusts the MAC-layer packet size based on local estimate of staggered collision probability. It is demonstrated that the proposed approach can greatly improve the effective throughput of WLAN and reduce video frame transfer delay. [ABSTRACT FROM AUTHOR]

Research of human-centered computing systems in industry should not avoid advances in visual display technology for safety, warning, and interaction. Novel 3D displays that present information in real depth offer potential benefits. Previous research has studied depth in visual search but depth was mostly not realized by real physical separation. Many areas of Human Factors could be augmented with the study and evaluation for operation of novel 3D displays. Such a study was presented to better understand the effects of real physical depth in association with depth redundantly coded with another feature (an additional mark on a target) distinguishing it from distracters and target location on visual search in a depth display. Target location was studied as the row or column in the visual field of view the target was positioned and also in terms of eccentricity outwardly from the center of the display. In general, depth was found to be of benefit when redundantly coded with another attribute for guiding attention. Targets were not found as fast when the target's location was further from the center fixation point, and interactions between target distinction (depth, mark, or depth+mark) and target location provide implications for designers. [ABSTRACT FROM AUTHOR]

The visualization of high resolution video on small mobile devices is still a great challenge today. Most critical are the limited display resolution and different aspect ratios of handheld mobile devices. So far, there is no retargeting algorithm available that guarantees good results for all videos. We introduce a new video retargeting approach that reduces the resolution while preserving as much of the relevant content as possible. A central component of the system selects the most suitable algorithm to adapt a given shot. We have implemented two retargeting algorithms: a region of interest ( ROI) based technique, and a fast implementation of seam carving for size adaptation of videos ( FSCAV). The ROI-based retargeting detects important regions like faces, objects, text, and contrast-based saliency regions. A rectangular window within the larger frame is selected that defines the visible area of the target video. If several relevant regions are detected, an artificial camera motion (pan, tilt, or zoom) may change the selected view within a shot. For seam carving, we present two extensions: The first reduces the distortion of straight lines (lines may become curved or disconnected); the second avoids jitter in the target video, limits the large memory requirements and computational effort of seam carving, and makes it applicable to video retargeting. In addition, we present a heuristic that estimates the visual quality of the target video. If the quality drops below a threshold, the ROI-based retargeting is used for this shot. User evaluations confirm a very high visual quality of our approach. [ABSTRACT FROM AUTHOR]

Abstract: The approximation functions of the directivity of the light emitting diodes (LED) have been investigated. LEDs used in large scale LED video displays have been studied. LED directional properties among the other parameters define the video display image quality. The simplicity of an approximation function and ease of analytical handling have been targeted. These functions suppose to be used in display directivity engineering. Four candidate approximation functions were identified and their approximation performance analyzed. The evaluation is done on eight different type LEDs’ sample batches. These samples have been chosen to represent the variety of the main colors and the range of the most popular viewing angles used in large scale LED video displays design. The relative intensity approximation root mean square (RMS) error and approximation errors’ cross correlation have been used as performance estimation criteria. The radiometric intensity variation within a manufacturing lot was suggested as lower error bound. Approximation error variance was analyzed for various approximation ranges. Results of four candidate approximation functions’ performance on eight different type LEDs’ are presented. [Copyright &y& Elsevier]

With international trends of energy saving and low emissions, pursuing healthy and low-emission buildings as well as ensuring the quality of interior environments have become critical issues in the 21st century. Bymeans of applying critical flicker frequency to the quantitative assessment of objective visual fatigue, and using a visual fatigue questionnaire to evaluate subjective visual fatigue, this study attempts, in 500lux and 200lux lighting environments, to investigate the influence of visual fatigue on working performance when using visual display terminals. Changes in productivity as a result of subjective and objective visual fatigue under different artificial lights have been analysed. The outcome shows that with light-emitting diode lighting, the sense of alertness and productivity was better. In terms of productivity, the 200lux lighting environment was even better than the 500lux lighting standard for a general operation environment, as suggested by the Illumination Engineering Society. [ABSTRACT FROM AUTHOR]

One of the non-self-similar models which is capable of modeling self-similar traffic in networks and always attracts attention of researches is MMPP process. In other words, this model can produce bur sty traffics in data and video networks. In this paper, accuracy and preciseness of adapting MMPP on voice, data and video traffics are studied and the efficiency of input process of MMPP into high speed networks is reviewed based on queue model of MMPP/D/1. Then by means of advanced and MMPP-based algorithms such as LAMBDA, data and video fractal traffics are synthesized based on original trace and their efficiency are compared. We correct the algorithms in a manner that the coordination impreciseness resulted by the change in parameters of selfsimilar traffic, in particular, HURST parameter fades out. Our strategy for correcting the above algorithm is as follows: Whereas the number of MMPP states in adjustment process is low, we may not be able to cover all original packet trace. Therefore, if the number of MMPP states increases, we can solve the efficiency problems. [ABSTRACT FROM AUTHOR]

Objective: Effects of display size and dual display setting on preferred display and keyboard positions were evaluated.Background: User-preferred display position may vary as its size changes or when multiple displays are used. It is also not known whether the use of larger displays or multiple displays would influence positioning of the keyboard.Method: Participants (N = 19) who had normal visual acuity (20/30 or better) determined preferred positions of the display and the keyboard during a data entry task in four display setups (19, 24, 27.5, and dual 19 in.). The size of capital characters (3.2 mm high) was kept consistent between setups.Results: Preferred viewing distance ranged from 0.68 m (19-in. display) to 0.76 m (27.5-in. display). No significant differences in viewing distance and display height were found between the single 19-in. display and dual 19-in. displays setups. The preferred position of the keyboard was consistent between display setups.Conclusion: Participants placed larger displays farther and lower while maintaining the display top at or near eye height. Preferred position of the dual displays in landscape setting did not differ from that of a single display. It appears that the preferred display position varies with the vertical dimension of the overall viewable area of the display.Application: The results of this study can be used to determine the dimensions or adjustability of computer workstations for larger displays or multiple displays settings. [ABSTRACT FROM AUTHOR]

The article discusses a study that investigates human color discrimination ability among visual display terminal workers. The researchers examine the color discrimination in visual display terminals among 10 participants and use three illuminant colors including red, blue and white as independent variables. Study reveals that screen background and illuminant colors influenced human color discrimination ability.

A method for the analysis of fatigue parameters has been rarely researched in VDT operation. Up to now, fatigue was evaluated by changing of biological information. If signals regarding fatigue are detected, fatigue can be measured. The purpose of this study was an experiment and analysis method to extract parameters related to fatigue from the biological information during VDT operation using Independent Component Analysis (ICA). The experiment had 11 subjects, and examined light-load and heavy-load VDT operation. Measurement items were amount of work, number of mistakes, subjective symptoms, surface skin temperature (forehead and apex nasi), heart rate, skin blood flow of forearm, and respiratory rate. In the heavy-load operation group, number of mistakes and subjective symptom score were increased. Two-factor ANOVA was used for analysis. The result of number of mistakes was confirmed for the heavy load. After the moving averages of waveform were calculated, we extracted independent components by using ICA. The results of ICA suggest that the independent components increase according to accumulation of fatigue. Thus, the independent components would be a possible parameter of fatigue. However, further experiments should continue in order to obtain conclusive findings of our research. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(9): 47–57, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10033 [ABSTRACT FROM AUTHOR]

Abstract: Synchronous Digital Hierarchy (SDH) is a standard for data transmission over telecommunication networks which is often used for framing and synchronization at the physical layer. SDH networks can carry large payloads, but, at the same time, accommodate lower speed signals packed into elementary transport units. The price of this flexibility consists of a potential waste of capacity, due to the complexity of simultaneously determining an efficient signal packing and routing. We address the problem of maximizing the number of communication requests of a given set which can be routed so as to fulfill capacity restrictions (on links and encoders/decoders) and additional constraints imposed by the signal packing mechanism. Despite the technological complexity, we show that a flow formulation can still be provided including signal packing. This formulation shows a nice experimental behavior when tested on the video network of one major Italian broadcasting company. [ABSTRACT FROM AUTHOR]

Abstract: We propose a 3D video display technique that allows multiple viewers to see 3D images from a 360-degree horizontal arc without wearing 3D glasses. This technique uses a cylindrical parallax barrier and a one-dimensional light source array. We have developed an experimental display system using this technique. Since this technique is based on the parallax panoramagram, the parallax number and resolution are limited by the diffraction at the parallax barrier. In order to solve this problem, we improved the technique by revolving the parallax barrier. The improved technique was incorporated into two experimental display systems. The newer one is capable of displaying 3D color video images within a 200-mm diameter and a 256-mm height. Images have a resolution of 1254 circumferential pixels and 256 vertical pixels, and are refreshed at 30Hz. Each pixel has a viewing angle of 60 degrees that is divided into over 70 views so that the angular parallax interval of each pixel is less than 1 degree. These pixels are arranged on a cylindrical surface to allow for the produced 3D images to be observed from all directions. In this case, observers may barely perceive the discrete parallax. [Copyright &y& Elsevier]

Abstract: 3D video based on stereo/multi-view representations is becoming widely popular. Real-time encoding/decoding of such video is an important concern as the number and spatial/temporal resolution of views increase. We present a systematic method for design and optimization of multi-threaded multi-view video encoding/decoding algorithms using multi-core processors and provide benchmark results for real-time decoding. The proposed multi-core decoding architectures are compliant with the current MVC extension of H.264/AVC international standard, and enable multi-threaded processing with negligible loss of encoding efficiency and minimum processing overhead. Benchmark results show that multi-core processors and multi-threading decoding are necessary for real-time high-definition multi-view video decoding and display. [Copyright &y& Elsevier]

For children with complex communication needs, augmentative and alternative communication (AAC) devices offer a functional way to communicate thoughts and feelings. Despite many significant advances in the field, effective and efficient aided communication can remain a challenge for some clients and their partners. One critical element of aided AAC intervention is systematic attention to the design of the communication display itself. A well-designed display will foster communication outcomes; a poorly designed one might have the opposite effect. Surprisingly, to our knowledge there are no studies of the strategies that clinicians actually employ when putting together a display. In this research note, we examine, on a case-by-case basis, the strategies six clinicians used when constructing display pages, as a means of highlighting potential areas that might warrant systematic research on display design. [ABSTRACT FROM AUTHOR]

Background: Dry eye has shown a marked increase due to visual display terminal (VDT) use. It remains unclear whether reduced blinking while focusing can have a direct deleterious impact on the lacrimal gland function. To address this issue that potentially affects the life quality, we conducted a large-scale epidemiological study of VDT users and an animal study. Methodology/Principal Findings: Cross sectional survey carried out in Japan. A total of 1025 office workers who use VDT were enrolled. The association between VDT work duration and changes in tear film status, precorneal tear stability, lipid layer status and tear secretion were analyzed. For the animal model study, the rat VDT user model, placing rats onto a balance swing in combination with exposure to an evaporative environment was used to analyze lacrimal gland function. There was no positive relationship between VDT working duration and change in tear film stability and lipid layer status. The odds ratio for decrease in Schirmer score, index of tear secretion, were significantly increased with VDT working year (P = 0.012) and time (P = 0.005). The rat VDT user model, showed chronic reduction of tear secretion and was accompanied by an impairment of the lacrimal gland function and morphology. This dysfunction was recovered when rats were moved to resting conditions without the swing. Conclusions/Significance: These data suggest that lacrimal gland hypofunction is associated with VDT use and may be a critical mechanism for VDT-associated dry eye. We believe this to be the first mechanistic link to the pathogenesis of dry eye in office workers. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the effectiveness of a workstation ergonomic intervention for work-related posture and low back pain (LBP) in Video Display Terminal (VDT) workers. 100 VDT workers were selected to receive the ergonomic intervention, whereas 100 were assigned to a control group. The two groups were then crossed-over after 30 months from baseline. Follow-ups were repeated at 5, 12, and 30 months from baseline and then at 6 months following crossover. Outcomes: Work-related posture and LBP point-prevalence using the Rapid Entire Body Assessment method and a Pain Drawing, respectively. The ergonomic intervention at the workstation improved work-related posture and was effective in reducing LBP point-prevalence both in the first study period and after crossover, and these effects persisted for at least 30 months. In conclusion, our findings contribute to the evidence that individualized ergonomic interventions may be able to improve work-related posture and reduce LBP for VDT workers. [Copyright &y& Elsevier]

The aim of this study is to identify, by a brief ad hoc questionnaire, specific dimensions of perceived occupational stress that could be relevant in two different work conditions of female workers: visual display unit (VDU) operators, for whom the risk of work-related stress is already known in literature, and kindergarten teachers, for whom very few studies have examined this risk. A questionnaire, prepared specifically for workers, was filled in by 70 all-female kindergarten teachers and 70 all-female VDU operators. The two groups were matched for age and length of service. The questionnaire was examined by factor analysis and questionnaire single item scores. Total score and factor scores were examined between group comparison of means analysis. The level of significance was established at p<0.05. Kindergarten teachers show significantly higher values of the questionnaire total score than VDU operators, indicating a higher level of perceived stress related to their occupation. In particular, the factor scores concerning perceived load of work responsibilities, the first of the three factors accounting for the structure of the questionnaire (1. perceived load of work-responsibility; 2. independence and autonomy in performing work-duties; 3. negative features of work interfering with psycho-physical wellbeing) are significant between groups. Compared to VDU operators, kindergarten teachers perceive a more stressful condition of responsibility in taking independent decisions and autonomously managing their work. When appropriate comparisons are performed between groups of workers operating under different occupational conditions, it is possible to identify, using an ad hoc questionnaire, different sources of occupational stress which are effective in the work environment of different categories of female workers. [ABSTRACT FROM AUTHOR]

In this paper, a highly area-efficient controller for capacitive touch screen panels (TSPs) is proposed. The proposed controller uses a 10-bit successive approximation register analog-to-digital converter (SAR ADC) with an adder to compensate for the capacitance variation in the TSP and for the offset voltage variation in the charge amplifier of the sensing circuit. By using the proposed compensation method, the area of the controller can be reduced by 90.3% of the area of the conventional controllers. The measurement results showed that the signal-to-noise ratio (SNR) of the controller increases from 12.5 to 21.3 dB after compensation. Also, its spatial jitter decreases from ±1.5 to ±0.46 mm, which is 7% of the sensor pitch of 8 mm. [ABSTRACT FROM AUTHOR]

Objective: This study was designed to identify the effect of seat support characteristics on the neck and trunk muscles and forward head posture of visual display terminal (VDT) workers working at computers. Participants: 22 VDT workers with forward head posture were asked to perform computer work. Methods: Surface electromyography recorded the five neck and trunk muscles Forward head angle was analyzed with a 3-D motion analysis system. The significance of differences in the seat supports (hard, spongy, unstable) was tested by repeated one-way ANOVA with the significance cutoff set at α = 0.05. Results: Computer work seated on an unstable cushion-ball as compared to a spongy soft-cushion seat support showed significantly lower midcervical and L5 paraspinal muscle activity and significantly higher lower trapezius and internal oblique abdominal muscle activity. The mean forward head angle decreased in the order of spongy, hard, and unstable seat supports. Conclusions: An unstable cushion-ball seat support may prevent work-related neck and upper limb disorders associated with forward head posture. [ABSTRACT FROM AUTHOR]

This study explored the effects of color combinations and polarity on user preferences and EEC responses using an icon design for a visual display terminal. 72 college students (M=24.5 yr., SD=2.3 yr.) were tested. The seven color combinations of top 16% with rating scores (5-point scale) over 3.60 almost always included black or white as a target or background, including white-on-black, red-on-black, yellow-on-black, blue-on-white, and black-on-white; the other two preferred color combinations were yellow-on-blue and blue-on-yellow. The eight color combinations of the bottom 16% with rating scores under 2.38 almost always included green, turquoise, or purple as a target or background. Negative image polarity (higher luminance color image shown on a lower luminance color background) was preferred over positive image polarity (lower luminance color image shown on a higher luminance color background) by the subjects. The θ and α band power in the right hemisphere were greater than those in the left hemisphere during the experiment. There seemed to be no linear correlation between the rating scores of subjective preferences and brain wave power of θ and α bands, so the possibility of using brain wave power to measure subjective preference is questionable. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate whether representational sounds that capture the richness of experience of a collision enhance performance in braking to avoid a collision relative to other forms of warnings in a driving simulator. Background: There is increasing interest in auditory warnings that are informative about their referents. But as well as providing information about some intended object, warnings may be designed to set the occasion for a rich body of information about the outcomes of behavior in a particular context. These richly informative warnings may offer performance advantages, as they may be rapidly processed by users. Method: An auditory occasion setter for a collision (a recording of screeching brakes indicating imminent collision) was compared with two other auditory warnings (an abstract and an "environmental" sound), a speech message, a visual display, and no warning in a fixed-base driving simulator as interfaces to a collision avoidance system. The main measure was braking response times at each of two headways (1.5 s and 3 s) to a lead vehicle. Results: The occasion setter demonstrated statistically significantly faster braking responses at each headway in 8 out of 10 comparisons (with braking responses equally fast to the abstract warning at 1.5 s and the environmental warning at 3 s). Conclusion: Auditory displays that set the occasion for an outcome in a particular setting and for particular behaviors may offer small but critical performance enhancements in time-critical applications. Application: The occasion setter could be applied in settings where speed of response by users is of the essence. [ABSTRACT FROM AUTHOR]

Electroencephalogram measures have frequently been shown to be highly sensitive to variations in task conditions; however, research on the effects of memory load on EEG response and Visual Display Terminal (VDT) performance is lacking. Data from 19 college students were analyzed for effects of memory load and polarity on VDT performance. Included also were modulation of the EEC distribution around the cerebrum, the inferred source of operation of working memory and comprehension. Analyses indicated that the effects of memory load on finish time were statistically significant. The theta (0) band at FP1 and FF2 had larger change in power than at T6, showing a large effect between memory load and frontal lobe function. This experiment on polarity and EEC response indicated the power change in the 0 band was stronger for positive contrast than negative; however, the polarity of the display had no statistically significant effect on EEC response. [ABSTRACT FROM AUTHOR]

Automatic face indexing is an important technique for realizing actor-based video services in an IPTV environment. This paper proposes a novel face indexing system that takes advantages of the internet connection of an STB to construct a FR engine that is equipped with a high number of training face images. In addition, we use a face clustering technique to obtain multiple face images of the same subject from a sequence of video frames. The clustered face images are combined using a weighted feature fusion scheme, resulting in a considerable enhancement in face indexing accuracy. The effectiveness of the proposed system is validated using more than 300,000 video frames, collected from Jive video clips containing drama or movie content. The experimental results show that the proposed system can achieve a face annotation accuracy that is feasible for practical applications. [ABSTRACT FROM AUTHOR]

This paper introduces a new technique for image bit-depth scaling for display devices. Conventional bit-depth scaling methods such as spatial 2D filtering and dithering algorithms suffer from false contours or dithered pattern artifacts, which significantly deteriorate image quality in display devices. In this paper, we propose a spatio-temporal 3D adaptive noise shaping filter whose coefficients are varied according to the characteristics of the input video signal. This filter minimizes the quantization error by adaptively altering the spectral shape of the error such that it does not produce visual annoyance in the reduced bit-resolution images. Experimental result shows that the proposed method effectively reduces the false contouring and dithered pattern artifacts compared with the conventional and current methods. [ABSTRACT FROM AUTHOR]

Analogy is a powerful heuristic for problem solving. In design, where designers are constantly exposed to visual stimuli, visual analogies are considered to be particularly helpful. To date, however, few researchers have given enough attention to visual analogy and visual displays in design contexts. This study deals with the use of these tools by investigating the effect that expertise has on them, in ill-defined and well-defined problem solving. Novice and experienced designers solved both types of design problem with exposure to visual displays and with the requirement to use visual analogy. Results showed that when visual displays and instructions to use analogy were available no expertise differences existed in well-defined problem solving. However, with the availability of only visual displays, architects tend to perform better than students. Without guidance to use analogy, students found difficulty in spontaneous recall of visual displays as candidate analogues in well-defined problems. In ill-defined problem solving, architects performed better than novice students in the use of both analogy and visual displays. However, no differences were found between the experienced designers and the advanced students in any experimental condition in this problem context. [ABSTRACT FROM AUTHOR]

The aim of the present study is to compare the duration of computer use assessed through a software package and through self-report by questionnaire. Applied in a large Public Administration, the software package led altogether to a remarkable reduction in the number of workers reaching the duration of use which requires medical examination. Nevertheless, it highlighted that self-reporting of a considerable number of workers had underestimated the computer use. The consistency with Italian laws is also discussed. [ABSTRACT FROM AUTHOR]

In this study, the authors analyzed the association between video display terminal (VDT) use before and during the three trimesters of pregnancy and risk of small-for-gestational-age (SGA) birth in a case-control study. The cases for this study were 555 women who delivered SGA births. The controls were 1,966 women who gave birth at term to healthy infants of normal weight. In terms of the length of exposure, the odds ratios (OR) of SGA birth were 1.2; for less than one hour and 1.3 for between two and 20 hours per week. For higher usage (more than 20 hours per week), the OR was 1.2 (95% CI: [Confidence Interval] 0.91.7). The authors conclude that this study does not show any association between VDT use and risk of SGA birth. [ABSTRACT FROM AUTHOR]

Background: Musculoskeletal disorders (MSDs) due to repetitive work are common in manufacturing industries, such as the automotive industry. However, it's still unclear which MSDs of the upper limb are to be expected in the automotive industry in a first aid unit as well as in occupational precaution examinations. It is also unclear which examination method could be performed effectively for practical reasons and under rehabilitation aspects. Additionally, it was to discuss whether the conception of unspecific description for MSDs has advantages or disadvantages in contrast to a precise medical diagnosis. Methods: We investigated the health status of two study populations working at two automotive plants in Germany. The first part included 67 consecutive patients who were seen for acute or chronic MSDs at the forearm over a 4-month period at the plants' medical services. Information about patients' working conditions and musculoskeletal symptoms was obtained during a standardized interview, which was followed by a standardized orthopedic-chiropractic physical examination. In the second part, 209 workers with daily exposure to video display terminals (VDT) completed a standardized questionnaire and were examined with function-oriented muscular tests on the occasion of their routine occupational precaution medical check-up. Results: The majority of the 67 patients seen by the company's medical services were blue-collar works from the assembly lines and trainees rather than white-collar workers from offices. Rates of musculoskeletal complaints were disproportionately higher among experienced people performing new tasks and younger trainees. The most common MSD in this group were disorders of flexor tendons of the forearm. By contrast, among the 209 employees working at VDT disorders of the neck and shoulders were more common than discomfort in the forearm. A positive tendency between restricted rotation of the cervical vertebrae and years worked at VDT was observed. In addition, only less than 8% of unspecific disorders of the upper limb (esp. wrist and forearm) were found. Conclusions: Functional tests for the upper limb seemed to be very helpful to give precise medical advice to the employees to prevent individual complaints. The results are also helpful for developing specific training programs before beginning new tasks as well as for rehabilitation reasons. There's no need to use uncertain terminology (such as RSI) as it may not be representative of the actual underlying disorders as diagnosed by more thorough physical examinations. [ABSTRACT FROM AUTHOR]

This multimedia essay combines words and images in a creative performance drawn from our 2009 cross-Canada Whistlestop Project,1 a study of the diverse art practices of Canadian popular educators involved in the women's movement. We focus on the Tofino Whistlestop on Vancouver Island on the Pacific Coast, the most westerly point on this research-by-rail journey, which began on the Atlantic coast. The eight participants at The Common Loaf Bake Shop in Tofino represented diverse art forms: arts-researcher Dorothy; arts-researcher and photographer Anita; baker-designer Maureen; painter-collagist-muralist Marla; flamenco dancer Thérèse; baker-mosaic artist Stephanie; poet-writer Chris; and, poet-writer-videographer John. This essay unfolds as a show and tell of the research participants' art practices as they constitute popular education in the context of arts-based action research methodology of Appreciative Inquiry (AI) to generate personal and collective stories of life-affirming experiences of art as popular education. This video essay highlights the relational art of story- telling and story-receiving through gesture, performance, and symbol. [ABSTRACT FROM AUTHOR]

In three experiments, the rate of acquisition of information from a visual display was measured, using Sperling's method of backward masking (Sperling, 1963). Experiment I (which included a control for letter redundancy) showed that the rate of acquisition from an array of letters or words is determined not by the number of visual features or letters to be processed, but by the number of names into which they are to be encoded. In a second, control experiment, no effect was found on acquisition rate of restricting the letter ensemble-size. The third experiment showed that the time needed to identify words of the same frequency of occurrence was identical for words of three or six letters and of one or two syllables. The results are contrasted with those obtained in RT and comparison tasks. They are interpreted as evidence that (1) the backward masking paradigm provides a direct measure of word identification latency; (2) visually presented words are processed as wholes: that is, prior to word identification there is no intermediate stage of representation — not subject to backward masking — in units (e.g., syllables, spelling patterns) smaller than a complete word; (3) words are initially represented in an abstract lexical code, which does not reflect either visual or motor attributes of the word name. [ABSTRACT FROM AUTHOR]

An empirical study was carried out to examine the effects of color combination and ambient illumination on visual perception time using TFT-LCD. The effect of color combination was broken down into two subfactors, luminance contrast ratio and chromaticity contrast. Analysis indicated that the luminance contrast ratio and ambient illumination had significant, though small effects on visual perception. Visual perception time was better at high luminance contrast ratio than at low luminance contrast ratio. Visual perception time under normal ambient illumination was better than at other ambient illumination levels, although the stimulus color had a confounding effect on visual perception time. In general, visual perception time was better for the primary colors than the middle-point colors. Based on the results, normal ambient illumination level and high luminance contrast ratio seemed to be the optimal choice for design of workplace with video display terminals TFT-LCD. [ABSTRACT FROM AUTHOR]

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PREVIOUS RESEARCH HAS DEMONSTRATED THAT MUSICAL soundtracks can influence the emotional impact, interpretation, and remembering of visual information. The present research examines the reverse relationship and whether visual information influences the perception and memory of music. In Experiment 1, listeners were presented with affectively ambiguous tunes paired with visual displays varying in their affect (positive, negative) and format (video, montage), or a control condition (no visual information at all). After each, participants were asked to provide a set of perceptual ratings that evaluated different melody characteristics and qualities of the visual displays. Results showed that both the affect and format of visual information differentially influenced the way a melody was perceived. Experiment 2 extended these findings by revealing that the affect of visual displays distorted melody recognition in a mood congruent fashion. These results are discussed in terms of their theoretical implications for audiovisual processing. [ABSTRACT FROM AUTHOR]

When high-quality video is delivered via a bandwidth-limited network, one solution is to reduce the spatial resolution of the bitstream before transmission. Downsizing transcoding is adopted as an efficient tool to reduce the spatial resolution of the precoded bitstream. Since the downsizing process and the coding process both apply a low-pass filtering operation on the picture, the reconstructed video may result in serious blocking artifact. In this paper, pre- and post-shift filters are considered in the transcoding process. The block boundary is shifted between the downsizing process and the coding process. This reduces the blocking effect in downsizing transcoding. Experimental results show that the proposed scheme can efficiently remove the blocking effect without introducing high computation. [ABSTRACT FROM AUTHOR]

Multiple-camera systems are currently widely used in research and development as a means of capturing and synthesizing realistic 3-D video content. Studio systems for 3-D production of human performance are reviewed from the literature, and the practical experience gained in developing prototype studios is reported across two research laboratories. System design should consider the studio backdrop for foreground matting, lighting for ambient illumination, camera acquisition hardware, the camera configuration for scene capture, and accurate geometric and photometric camera calibration. A ground-truth evaluation is performed to quantify the effect of different constraints on the multiple-camera system in terms of geometric accuracy and the requirement for high-quality view synthesis. As changing camera height has only a limited influence on surface visibility, multiple-camera sets or an active vision system may be required for wide area capture, and accurate reconstruction requires a camera baseline of 25°, and the achievable accuracy is 5-10-mm at current camera resolutions. Accuracy is inherently limited, and view-dependent rendering is required for view synthesis with sub-pixel accuracy where display resolutions match camera resolutions. The two prototype studios are contrasted and state-of-the-art techniques for 3-D content production demonstrated. [ABSTRACT FROM AUTHOR]