A material-independent method for determining liquid-crystal (LC) anchoring energy on rubbed polyimide (PI) surfaces has been devised. This method exploits the changes in the easy axis of rubbed PI film induced by exposure to linearly polarized UV (LPUV) light. The distribution of PI chains in a rubbed film is approximated by a Gaussian function and its width determined from the measured rotati...

Augmented Reality (AR) is a visualization technique in which computer generated graphics are superimposed over one's view of the real world. This paper reports results of recent studies in which navigation data was superimposed into a ship pilot's field of view, including a system recently instaIIed on the US military s High Speed Catamaran Joint Venture (HSV-Xl). The system displays both navig...

Adequate treatment of PTSD is a growing concern for the military. However, there is a shortage of qualified personnel available to apply this treatment. Virtual patient systems offer a novel technology to enhance the training needs of such health providers. This pilot project builds on previous work done with virtual patients and describes a novel scenario wherein a virtual patient is immersed ...

Virtual reality (VR) is a powerful multimedia visualization technique offering a range of mechanisms by which many new experiences can be made available. This paper deals with the basic nature of VR, the technologies needed to create it, and its potential, especially for helping disabled people. It also offers an overview of some examples of existing VR systems.

BACKGROUND For HIV-serodiscordant couples, integrated delivery of antiretroviral therapy (ART) for HIV-positive partners and time-limited pre-exposure prophylaxis (PrEP) for negative partners virtually eliminates HIV transmission. Standardized messaging, sensitive to the barriers and motivators to HIV treatment and prevention, is needed for widespread scale-up of this approach. METHODS Within...

Attentional control (AC) and fear extinction learning are known to be involved in pathological anxiety. In this study we explored whether individual differences in non-emotional AC were associated with individual differences in the magnitude and gradient of fear extinction (learning and recall). In 50 individuals with fear of spiders, we collected measures of non-emotional AC by means of self-r...

This paper proposed a novel spatial-motion-constraints virtual fixtures (VFs) method for the human-machine interface collaborative technique. In our method, two 3D flexible VFs have been presented: warning pipe and safe pipe. And a potential-collision-detection method based on two flexible VFs has been proposed. The safe pipe constructs the safe workspace dynamically for the robot, which makes ...

An increasing number of functional brain imaging studies are employing computer-based virtual reality (VR) to study changes in brain activity during the performance of high-level psychological and cognitive tasks. We report the development of a VR radial arm maze that adapts for human use in a scanning environment with the same general experimental design of behavioral tasks as that has been us...

Although research supports the efficacy of exposure therapy for PTSD, some evidence suggests that exposure is under-utilized in general clinical practice. The purpose of this study was to assess licensed psychologists' use of imaginal exposure for PTSD and to investigate perceived barriers to its implementation. A total of 852 psychologists from three states were randomly selected and surveyed....

In this study, we addressed four related issues concerning the estimation of traveled distances in a distance-matching visual task, using a virtual reality (VR) setup. Firstly, we found that when explicit counting strategies were blocked by an interfering dual task, the performance of 35% of subjects was strongly impaired. Secondly, we found that, when encoding and test phases took place in sim...