scholarly journals Controlling Teleportation-Based Locomotion in Virtual Reality with Hand Gestures: A Comparative Evaluation of Two-Handed and One-Handed Techniques

Electronics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 715
Author(s):  
Alexander Schäfer ◽  
Gerd Reis ◽  
Didier Stricker
Keyword(s):  
Virtual Reality ◽  
Virtual Worlds ◽  
User Preferences ◽  
Interaction Techniques ◽  
Hand Gestures ◽  
Wide Range ◽  
Effectiveness And Efficiency ◽  
High Degree ◽  
Additional Hardware ◽  
Comprehensive Study

Virtual Reality (VR) technology offers users the possibility to immerse and freely navigate through virtual worlds. An important component for achieving a high degree of immersion in VR is locomotion. Often discussed in the literature, a natural and effective way of controlling locomotion is still a general problem which needs to be solved. Recently, VR headset manufacturers have been integrating more sensors, allowing hand or eye tracking without any additional required equipment. This enables a wide range of application scenarios with natural freehand interaction techniques where no additional hardware is required. This paper focuses on techniques to control teleportation-based locomotion with hand gestures, where users are able to move around in VR using their hands only. With the help of a comprehensive study involving 21 participants, four different techniques are evaluated. The effectiveness and efficiency as well as user preferences of the presented techniques are determined. Two two-handed and two one-handed techniques are evaluated, revealing that it is possible to move comfortable and effectively through virtual worlds with a single hand only.

Evaluating the Efficacy of Multi-Sensory Stimulations on Simulator Sickness and Sense of Presence during HMD-mediated VR Experience

2020 ◽  
Author(s):  
Simone Grassini ◽  
Karin Laumann ◽  
Virginia de Martin Topranin ◽  
Sebastian Thorp
Keyword(s):  
Virtual Reality ◽  
Sensory Input ◽  
Mechanical Vibration ◽  
Sensory Stimulation ◽  
Vestibular Stimulation ◽  
Simulator Sickness ◽  
Sense Of Presence ◽  
Wide Range ◽  
High Degree ◽  
Seat Vibration

Virtual reality (VR) is currently being used for a wide range of applications. However, a sense of discomfort during VR experiences (commonly referred to as simulator sickness), is an obstacle for acceptance of the technology outside the niche of tech enthusiasts. Some lines of evidence have shown that sensory input, especially related to vestibular stimulation, may reduce the symptoms related to simulator sickness and increase the sense of presence. This investigation aims at understanding how mechanical vibration can be used to improve user experience in VR, reducing symptoms of simulator sickness and increasing the sense of presence. Four different groups comprising a total of 80 participants were tested under different conditions of sensory input (visual and vibratory, visual and auditory, visuo-auditory and vibratory, and visual only), during a VR roller-coaster experience. A questionnaire was used as the research instrument to evaluate both the sense of presence and the degree of simulator sickness experienced in VR. No significant differences in simulator sickness or presence were found between the groups exposed to seat vibration and/or audio. However, female participants experienced higher sense of presence when vibration was included. For participants experiencing a high degree of simulator sickness, vibration improved the experienced sense of presence, and the inclusion of vibration (but not sound) decreased the level of sickness-related disorientation. The inclusion of multi-sensory stimulation in VR revealed possibilities to improve the experience in some user categories; however, the use of vibration stimulation requires further research to be proven effective for the general public.Keywords: virtual reality, simulator sickness, presence, HMDs, vibration

Understanding Conformational Entropy in Small Molecules

2020 ◽  
Author(s):  
Lucian Chan ◽  
Garrett Morris ◽  
Geoffrey Hutchison
Keyword(s):  
Small Molecules ◽  
Degrees Of Freedom ◽  
Absolute Error ◽  
Low Energy ◽  
Standard Entropy ◽  
Free Energies ◽  
Conformational Entropy ◽  
Wide Range ◽  
High Degree ◽  
Empirical Corrections

The calculation of the entropy of flexible molecules can be challenging, since the number of possible conformers grows exponentially with molecule size and many low-energy conformers may be thermally accessible. Different methods have been proposed to approximate the contribution of conformational entropy to the molecular standard entropy, including performing thermochemistry calculations with all possible stable conformations, and developing empirical corrections from experimental data. We have performed conformer sampling on over 120,000 small molecules generating some 12 million conformers, to develop models to predict conformational entropy across a wide range of molecules. Using insight into the nature of conformational disorder, our cross-validated physically-motivated statistical model can outperform common machine learning and deep learning methods, with a mean absolute error ≈4.8 J/mol•K, or under 0.4 kcal/mol at 300 K. Beyond predicting molecular entropies and free energies, the model implies a high degree of correlation between torsions in most molecules, often as- sumed to be independent. While individual dihedral rotations may have low energetic barriers, the shape and chemical functionality of most molecules necessarily correlate their torsional degrees of freedom, and hence restrict the number of low-energy conformations immensely. Our simple models capture these correlations, and advance our understanding of small molecule conformational entropy.

Cerebellotrigeminal Dermal Dysplasia (Gómez-López-Hernández Syndrome)

2018 ◽  
Vol 16 (05) ◽  
pp. 362-368 ◽  
Author(s):  
Federica Sullo ◽  
Agata Polizzi ◽  
Stefano Catanzaro ◽  
Selene Mantegna ◽  
Francesco Lacarrubba ◽  
...  
Keyword(s):  
De Novo ◽  
Chromosomal Rearrangements ◽  
Number Of Patients ◽  
Wide Range ◽  
Visual Problems ◽  
Neurodevelopmental Abnormalities ◽  
Clinical Triad ◽  
High Degree ◽  
Motor Handicap

Cerebellotrigeminal dermal (CTD) dysplasia is a rare neurocutaneous disorder characterized by a triad of symptoms: bilateral parieto-occipital alopecia, facial anesthesia in the trigeminal area, and rhombencephalosynapsis (RES), confirmed by cranial magnetic resonance imaging. CTD dysplasia is also known as Gómez-López-Hernández syndrome. So far, only 35 cases have been described with varying symptomatology. The etiology remains unknown. Either spontaneous dominant mutations or de novo chromosomal rearrangements have been proposed as possible explanations. In addition to its clinical triad of RES, parietal alopecia, and trigeminal anesthesia, CTD dysplasia is associated with a wide range of phenotypic and neurodevelopmental abnormalities.Treatment is symptomatic and includes physical rehabilitation, special education, dental care, and ocular protection against self-induced corneal trauma that causes ulcers and, later, corneal opacification. The prognosis is correlated to the mental development, motor handicap, corneal–facial anesthesia, and visual problems. Follow-up on a large number of patients with CTD dysplasia has never been reported and experience is limited to few cases to date. High degree of suspicion in a child presenting with characteristic alopecia and RES has a great importance in diagnosis of this syndrome.

scholarly journals The effect of water immersion on vection in virtual reality

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Géraldine Fauville ◽  
Anna C. M. Queiroz ◽  
Erika S. Woolsey ◽  
Jonathan W. Kelly ◽  
Jeremy N. Bailenson
Keyword(s):  
Virtual Reality ◽  
Motion Sickness ◽  
Water Immersion ◽  
Sensory Information ◽  
Future Research ◽  
Visually Induced Motion Sickness ◽  
Wide Range ◽  
Induced Motion ◽  
Ground Condition ◽  
The Impact

AbstractResearch about vection (illusory self-motion) has investigated a wide range of sensory cues and employed various methods and equipment, including use of virtual reality (VR). However, there is currently no research in the field of vection on the impact of floating in water while experiencing VR. Aquatic immersion presents a new and interesting method to potentially enhance vection by reducing conflicting sensory information that is usually experienced when standing or sitting on a stable surface. This study compares vection, visually induced motion sickness, and presence among participants experiencing VR while standing on the ground or floating in water. Results show that vection was significantly enhanced for the participants in the Water condition, whose judgments of self-displacement were larger than those of participants in the Ground condition. No differences in visually induced motion sickness or presence were found between conditions. We discuss the implication of this new type of VR experience for the fields of VR and vection while also discussing future research questions that emerge from our findings.

scholarly journals Children’s interactive storytelling in Virtual Reality

2021 ◽  
Vol 1 (1) ◽  
pp. 48-67
Author(s):  
Dylan Yamada-Rice
Keyword(s):  
Virtual Reality ◽  
Digital Media ◽  
Virtual Worlds ◽  
Health And Safety ◽  
Design Elements ◽  
Interactive Storytelling ◽  
Head Mounted Display ◽  
Visual Style ◽  
Multimodal Methods ◽  
Core Points

This article reports on one stage of a project that considered twenty 8–12-years-olds use of Virtual Reality (VR) for entertainment. The entire project considered this in relation to interaction and engagement, health and safety and how VR play fitted into children’s everyday home lives. The specific focus of this article is solely on children’s interaction and engagement with a range of VR content on both a low-end and high-end head mounted display (HMD). The data were analysed using novel multimodal methods that included stop-motion animation and graphic narratives to develop multimodal means for analysis within the context of VR. The data highlighted core design elements in VR content that promoted or inhibited children’s storytelling in virtual worlds. These are visual style, movement and sound which are described in relation to three core points of the user’s journey through the virtual story; (1) entering the virtual environment, (2) being in the virtual story world, and (3) affecting the story through interactive objects. The findings offer research-based design implications for the improvement of virtual content for children, specifically in relation to creating content that promotes creativity and storytelling, thereby extending the benefits that have previously been highlighted in the field of interactive storytelling with other digital media.

Krypton 85 myocardial blood flow: precordial scintillation versus coronary sinus sampling

1965 ◽  
Vol 209 (4) ◽  
pp. 705-710 ◽  
Author(s):  
Michael D. Klein ◽  
Lawrence S. Cohen ◽  
Richard Gorlin
Keyword(s):  
Blood Flow ◽  
Myocardial Blood Flow ◽  
Coronary Sinus ◽  
Human Subjects ◽  
Radioactive Decay ◽  
Empirical Correction ◽  
Wide Range ◽  
Actual Flow ◽  
Flow Through ◽  
High Degree

Myocardial blood flow in human subjects was assessed by comparative simultaneous measurement of krypton 85 radioactive decay from coronary sinus and precordial scintillation. Empirical correction of postclearance background from precordial curves yielded a high degree of correlation between flows derived from the two sampling sites (r = .889, P < .001). Comparison of left and right coronary flows in nine subjects revealed similarity in flow through the two vessels over a wide range of actual flow values (r = .945, P < .001).

Interaction, engagement, and perceived interactivity in single-handed interaction

2016 ◽  
Vol 26 (5) ◽  
pp. 1134-1157 ◽  
Author(s):  
Donghee Shin ◽  
Myunggoon Choi ◽  
Jang Hyun Kim ◽  
Jae-gil Lee
Keyword(s):  
Behavioral Intention ◽  
Interaction Techniques ◽  
Content Type ◽  
Thumb Movement ◽  
Wide Range ◽  
Mobile Industry ◽  
Perceived Interactivity ◽  
The Subject ◽  
Definition Of ◽  
Practical Implications

Purpose The purpose of this paper is to examine the effects of interaction techniques (e.g. swiping and tapping) and the range of thumb movement on interactivity, engagement, attitude, and behavioral intention in single-handed interaction with smartphones. Design/methodology/approach A 2×2 between-participant experiment (technological features: swiping and tapping×range of thumb movement: wide and narrow) was conducted to study the effects of interaction techniques and thumb movement ranges. Findings The results showed that the range of thumb movement had significant effects on perceived interactivity, engagement, attitude, and behavioral intention, whereas no effects were observed for interaction techniques. A narrow range of thumb movement had more influence on the interactivity outcomes in comparison to a wide range of thumb movement. Practical implications While the subject of actual and perceived interactivity has been discussed, the issue has not been applied to smartphone. Based on the research results, the mobile industry may come up with a design strategy that balances feature- and perception-based interactivity. Originality/value This study adopted the perspective of the hybrid definition of interactivity, which includes both actual and perceived interactivity. Interactivity effect outcomes mediated by perceived interactivity.

Historical Dynamics

2018 ◽  
Author(s):  
Peter Turchin
Keyword(s):  
Religious Conversion ◽  
Synthetic Approach ◽  
Dynamical Processes ◽  
Factors Affecting ◽  
Historical Processes ◽  
Wide Range ◽  
Historical Dynamics ◽  
State Breakdown ◽  
Political Economic ◽  
High Degree

Many historical processes are dynamic. Populations grow and decline. Empires expand and collapse. Religions spread and wither. Natural scientists have made great strides in understanding dynamical processes in the physical and biological worlds using a synthetic approach that combines mathematical modeling with statistical analyses. Taking up the problem of territorial dynamics—why some polities at certain times expand and at other times contract—this book shows that a similar research program can advance our understanding of dynamical processes in history. The book develops hypotheses from a wide range of social, political, economic, and demographic factors: geopolitics, factors affecting collective solidarity, dynamics of ethnic assimilation/religious conversion, and the interaction between population dynamics and sociopolitical stability. It then translates these into a spectrum of mathematical models, investigates the dynamics predicted by the models, and contrasts model predictions with empirical patterns. The book's highly instructive empirical tests demonstrate that certain models predict empirical patterns with a very high degree of accuracy. For instance, one model accounts for the recurrent waves of state breakdown in medieval and early modern Europe. And historical data confirm that ethno-nationalist solidarity produces an aggressively expansive state under certain conditions (such as in locations where imperial frontiers coincide with religious divides). The strength of the book's results suggests that the synthetic approach advocated can significantly improve our understanding of historical dynamics.

Virtual Reality (VR) in Pediatrics: Innovative Perspectives With Special Reference To Clinical Applications and Pediatric Rehabilitation

2021 ◽  
Author(s):  
Stefan Bittmann
Keyword(s):  
Virtual Reality ◽  
Virtual Environment ◽  
Virtual Worlds ◽  
Virtual World ◽  
Mixed Reality ◽  
Clinical Applications ◽  
Virtual Space ◽  
Data Glove ◽  
Input Devices ◽  
Head Mounted Displays

Virtual reality (VR) is the term used to describe representation and perception in a computer-generated, virtual environment. The term was coined by author Damien Broderick in his 1982 novel “The Judas Mandala". The term "Mixed Reality" describes the mixing of virtual reality with pure reality. The term "hyper-reality" is also used. Immersion plays a major role here. Immersion describes the embedding of the user in the virtual world. A virtual world is considered plausible if the interaction is logical in itself. This interactivity creates the illusion that what seems to be happening is actually happening. A common problem with VR is "motion sickness." To create a sense of immersion, special output devices are needed to display virtual worlds. Here, "head-mounted displays", CAVE and shutter glasses are mainly used. Input devices are needed for interaction: 3D mouse, data glove, flystick as well as the omnidirectional treadmill, with which walking in virtual space is controlled by real walking movements, play a role here.

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