Search Results (112)

Natural walking locomotion in virtual reality (VR) allows intuitive movement through a virtual environment (VE), lower rates of simulator sickness, and increased immersion. However, it is limited by available play-space. Impossible spaces are VEs that use self-overlapping geometry to imitate larger play-spaces within a smaller area. Understanding how users interact with impossible spaces requires understanding how they perceive and remember VEs. However, it is unknown how impossible spaces impact users’ memory. An experiment was conducted comparing 32 participants’ memory from two conditions: natural walking in an impossible space and joystick movement in a similar non-impossible space. Participants were given up to 20 min to explore a virtual museum and were not instructed on what to remember. The experience was designed to allow participants to freely explore the VE at their own pace, allowing engagement duration to vary naturally. No significant differences were found between conditions for object or spatial memory; however, participants in the natural walking condition spent more time in the environment, revisited more areas, and were more confident identifying objects not encountered in the VE. This suggests natural walking in impossible spaces may be a viable alternative to traditional locomotion techniques. Full article

Artificial intelligence (AI) is now the computational core of smart building automation, acting across the entire cyber–physical stack. This review surveys peer-reviewed work on the integration of AI with indoor environmental quality (IEQ) and energy performance, distinguishing itself by presenting a holistic synthesis of the complete technological evolution from IoT sensors to generative AI. We uniquely frame this progression within a human-centric architecture that integrates digital twins of both the building (DT-B) and its occupants (DT-H), providing a forward-looking perspective on occupant comfort and energy management. We find that deep reinforcement learning (DRL) agents, often developed within physics-calibrated digital twins, reduce annual HVAC demand by 10–35% while maintaining an operative temperature within ±0.5 °C and CO₂ below 800 ppm. These comfort and IAQ targets are consistent with ASHRAE Standard 55 (thermal environmental conditions) and ASHRAE Standard 62.1 (ventilation for acceptable indoor air quality); keeping the operative temperature within ±0.5 °C of the setpoint and indoor CO₂ near or below ~800 ppm reflects commonly adopted control tolerances and per-person outdoor air supply objectives. Regarding energy impacts, simulation studies commonly report higher double-digit reductions, whereas real building deployments typically achieve single- to low-double-digit savings; we therefore report simulation and field results separately. Supervised learners, including gradient boosting and various neural networks, achieve 87–97% accuracy for short-term load, comfort, and fault forecasting. Furthermore, unsupervised models successfully mine large-scale telemetry for anomalies and occupancy patterns, enabling adaptive ventilation that can cut sick building complaints by 40%. Despite these gains, deployment is hindered by fragmented datasets, interoperability issues between legacy BAS and modern IoT devices, and the computer energy and privacy–security costs of large models. The key research priorities include (1) open, high-fidelity IEQ benchmarks; (2) energy-aware, on-device learning architectures; (3) privacy-preserving federated frameworks; (4) hybrid, physics-informed models to win operator trust. Addressing these challenges is pivotal for scaling AI from isolated pilots to trustworthy, human-centric building ecosystems. Full article

Maritime training increasingly employs conventional full-mission bridge simulators (FMBS) and virtual reality (VR). This study aims to compare the incidence and severity of simulator sickness induced by a conventional FMBS and an equivalent VR system during a maritime navigation task. Thirty-two final-year maritime students with no prior VR experience participated in two 30 min sessions (conventional FMBS first, then VR after a minimum two-day break), performing an identical navigational watch scenario as observers. Pre- and post-session SSQ scores were collected using a standardized questionnaire, supplemented by post-study qualitative interviews. The results indicated no significant change in SSQ scores following the conventional simulator session. In the VR session, a slight increase in Total SSQ and in Oculomotor and Disorientation subscales was observed (uncorrected p-values < 0.05), but none of these remained significant after applying a Holm–Bonferroni correction. The Nausea subscale did not increase in either condition. Notably, participants’ baseline SSQ scores were lower before the VR trial than before the conventional trial, suggesting a possible novelty effect. Qualitative feedback reflected VR’s high immersion yet also some physical discomfort (e.g., headset weight and visual resolution), with most participants preferring the conventional simulator for longer training. Overall, while VR’s current hardware had comfort limitations, using a standard calm-weather training scenario in VR produced only a minimal, statistically non-significant increase in simulator sickness compared to the conventional simulator. Full article

Background: This review investigates the use of virtual and augmented reality games in dementia care. It provides an insight into the last 13 years of research, including the earliest publications on this topic, and takes a systematic and bibliographic approach. Methods: We sourced research publications from three different scientific databases (PubMed, Scopus, and APA PsycInfo) for this publication. We chose the PRISMA approach and categorized the studies according to the publisher. A set of 12 variables was defined across three categories (bibliographic, medical, and technical). Results: Of the 389 identified articles, 36 met the inclusion and exclusion criteria. After a phase of pilot studies mainly being conducted, the number of publications increased by four times but decreased again in 2023. Dominating were pilot and feasibility studies; 8 out of the 36 trials were RCTs. The median trial population was 24, and the protocols were performed for an average of 10 weeks, with two 40-min sessions a week. Simulator sickness was reported but not by the majority of participants. A total of 59% of the studies used fully immersive 3D-VR systems. We identified only three publications that provided high immersion quality. These findings indicate the positive effects of using virtual and augmented reality systems on participants’ cognitive function and mood. Conclusions: This publication focuses on the technical aspects of the applied technologies and immersion levels of the patients. Using augmented and virtual reality methods to improve the quality of life and physical interaction of dementia patients shows the potential to enhance cognitive functioning in this population, but further investigation and multicenter RCTs are needed. There are strong indications that this research branch has high potential to benefit both caretakers and patients. Full article

Background: Acute mountain sickness (AMS) is a prevalent and potentially life-threatening condition caused by rapid exposure to high-altitude hypoxia, affecting pulmonary and neurological functions. Tongqiao Jiuxin Oil (TQ), a traditional Chinese medicine formula composed of aromatic and resinous ingredients such as sandalwood, agarwood, frankincense, borneol, and musk, has been widely used in the treatment of cardiovascular and cerebrovascular disorders. Clinical observations suggest its potential efficacy against AMS, yet its pharmacological mechanisms remain poorly understood. Methods: The chemical profile of TQ was characterized using UHPLC-Q-Exactive Orbitrap HRMS. Network pharmacology was applied to predict the potential targets and pathways involved in AMS. A rat model of AMS was established by exposing animals to hypobaric hypoxia (~10% oxygen), simulating an altitude of approximately 5500 m. TQ was administered at varying doses. Physiological indices, oxidative stress markers (MDA, SOD, GSH), histopathological changes, and the expression of hypoxia- and apoptosis-related proteins (HIF-1α, VEGFA, EPO, Bax, Bcl-2, Caspase-3) in lung and brain tissues were assessed. Results: A total of 774 chemical constituents were identified from TQ. Network pharmacology predicted the involvement of multiple targets and pathways. TQ significantly improved arterial oxygenation and reduced histopathological damage in both lung and brain tissues. It enhanced antioxidant activity by elevating SOD and GSH levels and reducing MDA content. Mechanistically, TQ downregulated the expression of HIF-1α, VEGFA, EPO, and pro-apoptotic markers (Bax/Bcl-2 ratio, Caspase-3), while upregulated Bcl-2, the anti-apoptotic protein expression. Conclusions: TQ exerts protective effects against AMS-induced tissue injury by improving oxygen homeostasis, alleviating oxidative stress, and modulating hypoxia-related and apoptotic signaling pathways. This study provides pharmacological evidence supporting the potential of TQ as a promising candidate for AMS intervention, as well as the modern research method for multi-component traditional Chinese medicine. Full article

Background: Emerging evidence indicates that some individuals recovering from COVID-19 develop persistent symptoms, including fatigue, pain, cognitive difficulties, and psychological distress, commonly known as Long COVID. These symptoms often overlap with those seen in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME), underscoring the need for integrative, non-pharmacological interventions. This Phase II controlled trial aimed to evaluate the feasibility and preliminary efficacy of Heart Rate Variability Biofeedback (HRV-BF) in individuals with Long COVID who meet the diagnostic criteria for CFS/ME. Specific objectives included assessing feasibility indicators (drop-out rates, side effects, participant satisfaction) and changes in fatigue, depression, anxiety, pain, and health-related quality of life. Methods: Participants were assigned alternately and consecutively to the HRV-BF intervention or Treatment-as-usual (TAU), in a predefined 1:1 sequence (quasirandom assignment). The intervention consisted of 10 HRV-BF sessions, held twice weekly over 5 weeks, with each session including a 10 min respiratory preparation and 40 min of active training. Results: The overall drop-out rate was low (5.56%), and participants reported a generally high level of satisfaction. Regarding side effects, the mean total Simulator Sickness Questionnaire score was 24.31 (SD = 35.42), decreasing to 12.82 (SD = 15.24) after excluding an outlier. A significantly greater improvement in severe fatigue was observed in the experimental group (H = 4.083, p = 0.043). When considering all outcomes collectively, a tendency toward improvement was detected in the experimental group (binomial test, p < 0.0001). Conclusions: HRV-BF appears feasible and well tolerated. Findings support the need for Phase III trials to confirm its potential in mitigating fatigue in Long COVID. Full article

With the development of electrification and intelligent technologies in vehicles, ride comfort issues represented by motion sickness have become a key constraint on the performance of autonomous driving. The occurrence of motion sickness is influenced by the comprehensive movement of the vehicle in the longitudinal, lateral, and vertical directions, involving ACC, LKA, active suspension, etc. Existing motion sickness control method focuses on optimizing the longitudinal, lateral, and vertical directions separately, or coordinating the optimization control of the longitudinal and lateral directions, while there is relatively little research on the coupling effect and coupled optimization of the longitudinal and vertical directions. This study proposes a coupled framework of ACC and active suspension control system based on MPC. By adding pitch angle changes caused by longitudinal acceleration to the suspension model, a coupled state equation of half-car vertical dynamics and ACC longitudinal dynamics is constructed to achieve integrated optimization of ACC and suspension for motion suppression. The suspension active forces and vehicle acceleration are regulated coordinately to optimize vehicle vertical, longitudinal, and pitch dynamics simultaneously. Simulation experiments show that compared to decoupled control of ACC and suspension, the integrated control framework can be more effective. The research results confirm that the dynamic coordination between the suspension and ACC system can effectively suppress the motion sickness, providing a new idea for solving the comfort conflict in the human vehicle environment coupling system. Full article

Hypoxia can adversely affect multiple organ systems. This study investigated the impact of intermittent hypoxia on serotonin levels and depression-like behaviors across distinct neuroanatomical regions. Sixteen adult female Wistar albino rats were divided into two groups: control (n = 8) and hypoxia (n = 8). The hypoxia group was exposed to a simulated altitude of 3000 for 5 h daily over 14 days. Behavioral assessments included locomotor activity (open field test) and depression-like behaviors (forced swimming test). Serotonin levels were quantified via ELISA in the prefrontal cortex, striatum, thalamus, hypothalamus, hippocampus, and serum. Intermittent hypoxia did not alter locomotor activity (p > 0.05) but significantly increased depression-like behavior (p < 0.05), accompanied by a pronounced reduction in swimming behavior (p < 0.0001), a marker associated with serotonergic function. Serotonin levels were significantly reduced in the prefrontal cortex (p < 0.005) and striatum (p < 0.05), while no changes were observed in other regions or serum (p > 0.05). These findings demonstrate that intermittent hypoxia induces depression-like behaviors and region-specific serotonin depletion, particularly in the prefrontal cortex and striatum. This underscores the need to evaluate hypoxia-related brain health implications in conditions such as sleep apnea and acute mountain sickness. Full article

Simulation sickness (SS) remains a challenge in virtual reality (VR) applications, especially in pedestrian safety research. This study investigates SS symptoms in VR environments, focusing on gender differences, exposure time, and user perceptions. A total of 145 participants were exposed to two VR pedestrian scenarios: a crosswalk and a sidewalk. The Simulator Sickness Questionnaire (SSQ) was used to assess symptoms of nausea, oculomotor disturbance, and disorientation. Results showed that female participants reported significantly higher SS symptoms than males, with the sidewalk scenario inducing greater overall SS. Additionally, perceived realism in the VR environment was associated with reduced symptoms, while perceived disengagement led to increased discomfort. These findings highlight the importance of user perceptions in mitigating SS and suggest that VR scenarios should be designed with attention to gender differences and environmental realism to improve user experience and safety. Full article

Path tracking is an essential task for autonomous driving (AD), for which controllers are designed to issue commands so that vehicles will follow the path of upper-level decision planning properly to ensure operational safety, comfort, and efficiency. Current path-tracking methods still face challenges in balancing tracking accuracy with computational overhead, and more critically, lack consideration for Motion Sickness (MS) mitigation. However, as AD applications divert occupants’ attention to non-driving activities at varying degrees, MS in self-driving vehicles has been significantly exacerbated. This study presents a novel framework, the Hybrid Supervised–Reinforcement Learning (HSRL), designed to reduce passenger discomfort while achieving high-precision tracking performance with computational efficiency. The proposed HSRL employs expert data-guided supervised learning to rapidly optimize the path-tracking model, effectively mitigating the sample efficiency bottleneck inherent in pure Reinforcement Learning (RL). Simultaneously, the RL architecture integrates a passenger MS mechanism into a multi-objective reward function. This design enhances model robustness and control performance, achieving both high-precision tracking and passenger comfort optimization. Simulation experiments demonstrate that the HSRL significantly outperforms Proportional–Integral–Derivative (PID) and Model Predictive Control (MPC), achieving improved tracking accuracy and significantly reducing passengers’ cumulative Motion Sickness Dose Value (MSDV) across several test scenarios. Full article

As in-vehicle display environments become increasingly common, addressing motion sickness has become essential due to the intensified visual and vestibular discrepancies introduced by media experiences within vehicles. Prior research highlights that minimizing the conflict between vestibular signals and visual motion perception is crucial for reducing motion sickness. This study aims to identify optimal viewing conditions and simulation settings for motion sickness reduction by experimentally adjusting field of view (FOV) and screen brightness. Specifically, the FOV is narrowed according to vehicle acceleration and angular speed, aligning with simulated vehicle motion through a motion simulator connected to a head-mounted display (HMD). The experimental results indicate that this approach can reduce motion sickness by up to 40%. Additionally, integrating the generated motion data with VR motion data enables a realistic simulation of in-vehicle conditions, suggesting that this method may enhance comfort in actual in-vehicle media environments. Full article

The adoption of immersive technologies, such as virtual reality (VR) and augmented reality (AR), is transforming sectors like healthcare, education, entertainment, and retail by offering innovative, simulated experiences. These technologies provide significant benefits, such as enhanced learning, improved patient outcomes, and innovative rehabilitation tools. However, their use also raises concerns about user comfort and potential health impacts. This systematic literature review examines the positive and negative health implications of immersive technologies, drawing insights from 104 peer-reviewed articles. The findings highlight therapeutic and rehabilitation benefits, such as treating anxiety and improving motor skills, alongside physical health concerns like eye strain and cybersickness, and mental health challenges, including cognitive overload and addiction. The study identifies key demographics most susceptible to these effects, such as children, the elderly, and individuals with pre-existing health conditions. Recommendations for mitigating risks include ergonomic device design, synchronized sensory inputs, and user training. This research underscores the need for the responsible and ethical development of immersive technologies, ensuring they enhance real-world experiences without compromising user well-being. Future studies should focus on long-term health implications, inclusive design, and establishing guidelines to maximize benefits while minimizing risks. Full article

Rhodiola crenulata (RC) is a traditional herb and functional food that has demonstrated beneficial effects in improving physical function, enhancing work capacity, alleviating fatigue, and preventing altitude sickness. Additionally, RC has shown promising effects in the treatment of non-alcoholic fatty liver disease (NAFLD), although its specific bioactive components and underlying mechanisms remain unclear. In this study, ultra-high-performance liquid chromatography–mass spectrometry (UHPLC-MS) combined with network pharmacology was employed to identify six potential bioactive compounds from the serum of rats treated with RC—Salidroside, Tyrosol, Crenulatin, Catechin gallate, Eriodictyol, and Rhodiooctanoside—that may contribute to its therapeutic effects on NAFLD. The efficacy of these compounds in improving NAFLD was assessed in vitro using HepG2 cells exposed to Palmitic acid (PA), and it was found that Catechin gallate exhibited a significant effect in reducing lipid accumulation in HepG2 cells. Furthermore, based on network pharmacology predictions, molecular docking studies suggested that the primary targets of Catechin gallate in alleviating fatty liver might include ABCB1, DYRK1A, PGD, and FUT4. Molecular dynamics simulations revealed stable binding interactions between Catechin gallate and these four target proteins. This study clarifies the material basis of RC in the treatment of NAFLD and provides a theoretical foundation for the application of RC and Catechin gallate as functional additives for the management of NAFLD. Full article

This paper presents a method to design a parameter adaptive suspension controller to boost ride comfort and to reduce motion sickness. According to recently published papers, combined motions of a sprung mass (SPMS) along heave and pitch directions tend to make motion sickness severe. To reduce motion sickness, it is necessary to design a controller which can reduce the heave and pitch vibrations of a SPMS. To avoid full-state feedback which is very difficult to implement in a real vehicle, a static output feedback (SOF) control is chosen as a feedback structure. With the SOF structure, linear quadratic SOF and parameter adaptive controllers are designed. When designing parameter adaptive controllers, an extended Kalman filter (EKF), equivalent to recursive least square (RLS), is selected for parameter adaptation. To verify performance of the controllers, simulation is performed on vehicle simulation tool. From simulation responses, it is checked whether the proposed parameter adaptive controllers are effective or not and which is the best controller, with respect to ride comfort and motion sickness. Full article

Model-Based Systems Engineering (MBSE) prioritizes system design through models rather than documents, and it is implemented with the Systems Modeling Language (SysML), which is the state-of-the-art language in academia and industry. Virtual Reality (VR), an immersive visualization technology, can simulate reality in virtual environments with varying degrees of fidelity. In recent years, the technology industry has invested substantially in the development of head-mounted displays (HMDs) and related virtual reality (VR) technologies. Various research has suggested that VR-based immersive design reviews enhance system issue/fault identification, collaboration, focus, and presence compared to non-immersive approaches. Additionally, several research efforts have demonstrated that the VR environment provides higher understanding and knowledge retention levels than traditional approaches. In recent years, multiple attempts have been made to visualize conventional 2D SysML diagrams in a virtual reality environment. To the best of the author’s knowledge, no empirical evaluation has been performed to analyze the benefits and drawbacks of visualizing SysML diagrams in a VR environment. Hence, the authors aimed to evaluate four key benefit types and drawbacks through experiments with human subjects. The authors chose four benefit types—Systems Understanding, Information Sharing, Modeling and Training Experience, and Digital Twin based on the MBSE value and benefits review performed by researchers and benefits claimed by the evaluations for similar visual formalism languages. Experiments were conducted to compare the understanding, interaction, and knowledge retention for 3D VR and conventional 2D SysML diagrams. The authors chose a ground-based telescope system as the system of interest (SOI) for system modeling. The authors utilized a standalone wireless HMD unit for a virtual reality experience, which enabled experiments to be conducted irrespective of location. Students and experts from multiple disciplines, including systems engineering, participated in the experiment and provided their opinions on the VR SysML implementation. The knowledge test, perceived evaluation results, and post-completion surveys were analyzed to determine whether the 3D VR SysML implementation improved these benefits and identified potential drawbacks. The authors utilized a few VR scenario efficacy measures, namely the Simulation Sickness Questionnaire (SSQ) and System Usability Scale (SUS), to avoid evaluation design-related anomalies. Full article