MULTI-OBJECTIVE OPTIMIZATION RESEARCH ON VR TASK SCENARIO DESIGN BASED ON COGNITIVE LOAD

To test the hypothesis that racial biases in opioid prescribing would be more likely under high levels of cognitive load, defined as the amount of mental activity imposed on working memory, which may come from environmental factors such as stressful conditions, chaotic workplace, staffing insufficiency, and competing demands, one's own psychological or physiological state, as well as from demands inherent in the task at hand. Two (patient race: White vs Black) by two (cognitive load: low vs high) between-subjects factorial design. Ninety-eight primary care physicians from the Veterans Affairs Healthcare System. Web-based experimental study. Physicians were randomly assigned to read vignettes about either a Black or White patient, under low vs high cognitive load, and to indicate their likelihood of prescribing opioids. High cognitive load was induced by having physicians perform a concurrent task under time pressure. There was a three-way interaction between patient race, cognitive load, and physician gender on prescribing decisions (P = 0.034). Hypotheses were partially confirmed. Male physicians were less likely to prescribe opioids for Black than White patients under high cognitive load (12.5% vs 30.0%) and were more likely to prescribe opioids for Black than White patients under low cognitive load (30.8% vs 10.5%). By contrast, female physicians were more likely to prescribe opioids for Black than White patients in both conditions, with greater racial differences under high (39.1% vs 15.8%) vs low cognitive load (28.6% vs 21.7%). Physician gender affected the way in which patient race and cognitive load influenced decisions to prescribe opioids for chronic pain. Future research is needed to further explore the potential effects of physician gender on racial biases in pain treatment, and the effects of physician cognitive load on pain treatment.

This paper describes a study aimed at developing and applying a method for comparing the user experience (UX) of virtual reality (VR) systems, in order to identify aspects that differentiate VR systems from a user perspective as well as aspects that users consider important when selecting a VR system. A within-subjects study was conducted, in which twelve participants played a VR game using four different VR systems (i.e., VR headsets and hand controllers). The UX was evaluated through semi-structured interviews and questionnaires. Headset comfort, fit, and perceived image quality as well as unrestricted mobility (i.e., untethered headsets) were identified as important aspects for the UX. Hand controllers that allowed more natural interaction were generally preferred. Image sharpness and headset comfort were considered the most important aspects for selecting a VR system. The study demonstrated that the method can be applied and generate insights into the UX of VR systems.

Background and Purpose: Repetitive practice improves function and facilitates cortical plasticity after stroke. Virtual reality (VR) systems have the potential to provide motivating and safe repetitive practice with minimal supervision. The purpose of this case study is to look at the effect of a VR system, activated by surface electromyography of dorsiflexors and plantarflexors, on gait velocity, function, and kinematics. Method: The first person randomized to the treatment group of a larger study was chosen for this case. She was 51 years old and 9 months poststroke. She received treatment 3 times per week for 8 weeks. Each 60-minute session consisted of both structured lower extremity exercise and VR ankle activities. Results: After intervention, the subject demonstrated increased gait speed and decreased time to perform the modified Emory Functional Ambulation Profile. Gait kinematics demonstrated improved ankle motion and plantarflexion moments at push off. Discussion: The improved gait speed, possibly due to increased ankle plantarflexion motion and moments, resulted in a more normalized trailing limb posture. This case study suggests that ankle to computer VR systems may help stroke patients improve gait function. This VR system has potential as an adjunctive therapy or home program requiring minimal supervision.

To effectively organize design elements in virtual reality (VR) scene design and provide evaluation methods for the design process, we built a user image space cognitive model. This involved perceptual engineering methods and optimization of the VR interface. First, we studied the coupling of user cognition and design features in the VR system via the Kansei Engineering (KE) method. The quantitative theory I and KE model regression analysis were used to analyze the design elements of the VR system’s human–computer interaction interface. Combined with the complex network method, we summarized the relationship between design features and analyzed the important design features that affect users’ perceptual imagery. Then, based on the characteristics of machine learning, we used a convolutional neural network (CNN) to predict and analyze the user’s perceptual imagery in the VR system, to provide assistance for the design optimization of the VR system design. Finally, we verified the validity and feasibility of the solution by combining it with the human–machine interface design of the VR system. We conducted a feasibility analysis of the KE model, in which the similarity between the multivariate regression analysis of the VR intention space and the experimental test was approximately 97% and the error was very small; thus, the VR intention space model was well correlated. The Mean Square Error (MSE) of the convolutional neural network (CNN) prediction model was calculated with a measured value of 0.0074, and the MSE value was less than 0.01. The results show that this method can improve the effectiveness and feasibility of the design scheme. Designers use important design feature elements to assist in VR system optimization design and use CNN machine learning methods to predict user image values in VR systems and improve the design efficiency. Facing the same design task requirements in VR system interfaces, the traditional design scheme was compared with the scheme optimized by this method. The results showed that the design scheme optimized by this method better fits the user’s perceptual imagery index, and thus the user’s task operation experience was better.

Digital restoration of fragmentary human skeletal remains: Testing the feasibility of virtual reality

With the rapid development of science and technology, virtual reality (VR) systems have developed rapidly. VR systems can be applied in many fields such as education, medical, military, and probing. According to the survey, the VR system will have a delay in the process of acquisition, transmission and processing, and more than 40% of the human body will have motion sickness after experiencing VR. The cause of motion sickness is delay. Accurate measurement of delays therefore helps to resolve motion sickness in the virtual world and provides guidance for the upgrade of these systems. In response to the existing problems, our research team designed a low-cost, high-performance experimental equipment that uses a single-chip microcomputer and a PIN photodiode as the hardware core of the delay detection device. The light intensity changes are used to determine the start and end of the detection. The algorithm calculates the delay time of the VR device.

Virtual reality (VR) technology is commonly used in entertainment applications; however, it has also been deployed in practical applications in more serious aspects of our lives, such as safety. To support people working in dangerous industries, VR can ensure operators manipulate standardized tasks and work collaboratively to deal with potential risks. Surprisingly, little research has focused on how people can collaboratively work in VR environments. Few studies have paid attention to the cognitive load of operators in their collaborative tasks. Once task demands become complex, many researchers focus on optimizing the design of the interaction interfaces to reduce the cognitive load on the operator. That approach could be of merit; however, it can actually subject operators to a more significant cognitive load and potentially more errors and a failure of collaboration. In this paper, we propose a new collaborative VR system to support two teleoperators working in the VR environment to remote control an uncrewed ground vehicle. We use a compared experiment to evaluate the collaborative VR systems, focusing on the time spent on tasks and the total number of operations. Our results show that the total number of processes and the cognitive load during operations were significantly lower in the two-person group than in the single-person group. Our study sheds light on designing VR systems to support collaborative work with respect to the flow of work of teleoperators instead of simply optimizing the design outcomes.

The evolution of Virtual Reality (VR) technology has contributed in all fields, including psychology. This evolution involves improvements in hardware and software allowing more immersive experiences. In a VR environment users can perceive the sensation of presence and feel immersed. These sensations are possible using VR devices as HMDs. Nowadays, the development of the HMDs has focused on improving their technical features to offer full immersion. In psychology, VR environments are research tools because they allow the use of new paradigms that are not possible to employ in a real environment. There are some applications for assessing spatial memory that use basic methods of HCI. However, VR systems that incorporate stereoscopy and physical movement have not yet been exploited in psychology. In this thesis, a novel VR system combining immersive, interactive and motion features was developed. This system was used for the assessment of the spatial memory and the evaluation of depth perception. For this system, a virtual maze task was designed and implemented. In this system, two different types of interaction were integrated: a locomotion-based interaction pedaling a fixed bicycle (condition1), and a stationary interaction using a gamepad (condition2). This system integrated two types of display systems: 1) The Oculus Rift; 2) A large stereo screen. Two studies were designed to determine the efficacy of the VR system using physical movement and immersion. The first study (N=89) assessed the spatial short term memory using the Oculus Rift and the two types of interaction The results showed that there were statistically significant differences between both conditions. The participants who performed the condition2 got better performance than participants who performed the condition1. However, there were no statistically significant differences in satisfaction and interaction scores between both conditions. The performance on the task correlated with the performance on other classical neuropsychological tests, revealing a verisimilitude between them. The second study (N=59) involved participants who had and who had not stereopsis. This study assessed the depth perception by comparing the two display systems. The participants performed the task using the condition2. The results showed that the different features of the display system did not influence the performance on the task between the participants with and without stereopsis. Statistically significant differences were found in favor of the HMD between the two conditions and between the two groups of participants regard to depth perception. The participants who did not have stereopsis and could not perceive the depth when they used other display systems (e.g. CAVE); however, they had the illusion of depth perception when they used the Oculus Rift. The study suggests that for the people who did not have stereopsis, the head tracking largely influences the 3D experience. The statistical results of both studies have proven that the VR system developed for this research is an appropriate tool to assess the spatial short-term memory and the depth perception. Therefore, the VR systems that combine full immersion, interaction and movement can be a helpful tool for the assessment of human cognitive processes as the memory. General conclusions from these studies are: 1) The VR technology and immersion provided by current HMDs are appropriate tools for psychological applications, in particular, the assessment of spatial short-term memory; 2) A VR system like the one presented in this thesis could be used as a tool to assess or train adults in skills related to spatial short-term memory; 3) The two types of interaction (condition1 and condition2) used for navigation within the virtual maze could be helpful to use with different collectives; 4) The Oculus Rift allows that the users without stereopsis can perceive the depth perception of 3D objects and have rich 3D experiences.

Generally, a virtual reality (VR) system cannot provide the realistic sound formed by the multi-channel audio signals to a user with the stereo headphone environment. In addition, the VR system has a gap between the visual scene and the sound because it supplies the audio signal having only a constant sound scene without respect to the change of the user's position. To solve these problems, we introduce the sound scene control of binaural sound. Binaural sound is a stereo realistic sound that can be generated by convolving a 10.1 channel audio signal with a head related transfer function (HRTF) coefficients which features all the paths from the multi-channel speaker layout to the ears in free space. However, since a binaural sound is generated using a fixed multi-channel layout and HRTF coefficients, the binaural sound has a constant sound scene and cannot reflect the user's movements. So, we apply the sound scene control scheme that modifies the binaural sound to allow the user's movement in the VR system. Initially, a multichannel layout is re-created according to the user's azimuth change and the original multi-channel signal is mapped to a new ultra multi-channel layout using a constant power panning law. Secondly, the sound level of the new multichannel audio signal is controlled by the user's distance change, using the characteristics of the sound level inversely proportional to distance. Finally, the final multi-channel audio signal is convolved with the HRTF coefficients to produce a binaural sound with the controlled sound scene. As a result, the proposed realistic audio sound generation method allows the current VR system to provide true VR service without distinction between the visual scenes and sounds.

Extended-Reality Technologies: An Overview of Emerging Applications in Medical Education and Clinical Care.

PurposeEmerging technologies, such as virtual reality (VR), have been influencing both the tourism supply side and tourists alike. The purpose of this study is to analyse VR research in tourism and to provide a comprehensive state-of-the-art review. As the technological connotation of the term VR has been changing and encompasses various VR systems with different capabilities, this paper aims to provide a systematic and structured overview. The overall objective of this paper is to contribute to a thorough understanding of VR research in tourism.Design/methodology/approachThis paper comprehensively reviews and analyses existing literature on VR in tourism, published from 1994 to February 2018. Using a wide variety of sources, these papers were examined so as to give a state-of-the-art literature review and to deepen one’s understanding of the diverse applications of VR in a tourism context. This paper also presents a novel classification of different VR systems according to the level of immersion and depicts their respective technological capabilities.FindingsThe advent of new VR hardware necessitates a distinction for different VR systems applied in the tourism sector. Research conducted during the past three years has been focussing on the application of head-mounted displays, which reflects the temporal development of VR technology. Regardless of the VR system, most studies examine VR as a marketing tool for promotion and communication purposes during the pre-travel phase, focussing on behavioural aspects. Advances in technology will yield new opportunities and application possibilities for the tourism industry.Originality/valueThe key contribution of this paper lies in its structural approach, which differentiates between non-, semi- and fully immersive VR systems in tourism, as well as the proposition of respective definitions. The concluding part of the paper proposes practical implications for tourism businesses together with directions for future studies.

There still lacks a collaborative framework that integrates existing and new virtual reality systems supporting remote collaboration for data visualization. The collaborative framework currently available might limit the collaborators for collaboration because it is not developed to support interaction with diverse 3D applications while using heterogeneous virtual reality (VR) systems remotely in a synchronized way. We will present our collaborative framework that supports remote collaboration across heterogeneous VR systems to interact with multiple 3D applications. This system is independent of any VR systems and can be used to interact collaboratively in real-time on a shared task. Additionally, we conducted a pilot study to gain perspective on the usability of the system for collaborative work across heterogeneous VR systems. We will present the results on the usability of the system, and the results obtained from the users are motivating and encouraging. Our system has the potential to increase task effectiveness and workflow because it enables shared and real-time interaction while remotely collaborating with diverse 3D applications across heterogeneous VR systems.

Virtual Reality (VR) systems are used to distract patients from their current condition and immerse them in a virtual world where they are able to do many virtual activities while receiving their treatment. It was observed that VR systems improve the patent state of mind thereby improving their immune system. In this paper we study the role of VR in improving pain threshold for chemotherapy and burn patients. Unfortunately not all patients are able to use VR equipments, for example burn patents are unable to use VR head mounts and gloves. To design a VR software and hardware that could be used for every patent is close to impossible. In this paper we introduce the benefits and challenges of using VR systems as an added therapy to reduce pain sensation; we also give the general technical requirements for such system.

Immersive engineering instruction: Using Virtual Reality to enhance students’ experience in the classroom

This paper describes a task-oriented approach to cope with the difference between the three dimensional (3D) space in a virtual reality (VR) system and that perceived by the user from its stereoscopic images with binocular disparity. This difference occurs for the reason that human visual perception is affected not only by binocular disparity but also by various kinds of visual cues. Although it is possible to set some of those cues consistent with each other when they are presented by a stereoscopic display, it is difficult to do the same for other cues especially vergence and focus. As the result, the users of VR systems often fail to manipulate virtual objects due to this difference. In this article, we propose to adjust the virtual space in a VR system through object manipulation by the user so that the user does not fail in each manipulation. We verified by experiments that this adjustment is effective to improve the rate of successful manipulation.