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1.
Appl Ergon ; 116: 104206, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38141524

RESUMO

Trams are experiencing a resurgence with worldwide network expansion driven by the need for sustainable and efficient cities. Trams often operate in shared or mixed-traffic environments, which raise safety concerns, particularly in hazardous situations. This paper adopts an international, mixed-methods approach, conducted through two interconnected studies in Melbourne (Australia) and Birmingham (UK). The first study involved qualitative interviews, while the second was an experimental study involving a virtual reality (VR) simulator and haptic master controller (i.e., speed lever). In tram operations, master controllers play a critical role in ensuring a smooth ride, which directly influences passenger safety and comfort. The objective was to understand how a master control system, enhanced with additional haptic feedback, could improve tram driver braking performance and perceptions in safety-critical scenarios. Interview results indicate that the use of the emergency brake is considered the final or ultimate choice by drivers, and their driving experience is a moderating factor in limiting its application. Combined with the experimental results, this paper highlights how implementing haptic feedback within a master controller can reduce the performance disparity between novice and experienced tram drivers.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Retroalimentação , Tecnologia Háptica , Veículos Automotores
2.
Sensors (Basel) ; 23(9)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37177658

RESUMO

Given the rise of automated vehicles from an engineering and technical perspective, there has been increased research interest concerning the Human and Computer Interactions (HCI) between vulnerable road users (VRUs, such as cyclists and pedestrians) and automated vehicles. As with all HCI challenges, clear communication and a common understanding-in this application of shared road usage-is critical in order to reduce conflicts and crashes between the VRUs and automated vehicles. In an effort to solve this communication challenge, various external human-machine interface (eHMI) solutions have been developed and tested across the world. This paper presents a timely critical review of the literature on the communication between automated vehicles and VRUs in shared spaces. Recent developments will be explored and studies analyzing their effectiveness will be presented, including the innovative use of Virtual Reality (VR) for user assessments. This paper provides insight into several gaps in the eHMI literature and directions for future research, including the need to further research eHMI effects on cyclists, investigate the negative effects of eHMIs, and address the technical challenges of eHMI implementation. Furthermore, it has been underlined that there is a lack of research into the use of eHMIs in shared spaces, where the communication and interaction needs differ from conventional roads.


Assuntos
Veículos Autônomos , Pedestres , Humanos , Computadores , Comunicação , Acidentes de Trânsito
3.
J Neurotrauma ; 40(1-2): 52-62, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35734899

RESUMO

There is a recognized need for objective tools for detecting and tracking clinical and neuropathological recovery after sports-related concussion (SRC). Although computerized neurocognitive testing has been shown to be sensitive to cognitive deficits after SRC, and some blood biomarkers have shown promise as indicators of axonal and glial damage, the potential utility of these measures in isolation and combination for assisting SRC diagnosis and tracking recovery is not well understood. To provide new insights, we conducted a prospective study of 64 male and female professional flat-track jockeys (49 non-SRC, 15 SRC), with each jockey undergoing symptom evaluation, cognitive testing using the CogSport battery, and serum biomarker quantification of glial fibrillary acidic protein (GFAP), tau, and neurofilament light (NfL) using a Simoa HD-X Analyzer. Measures were performed at baseline (i.e., pre-injury), and 2 and 7 days and 1 and 12 months after SRC. Symptoms were most pronounced at 2 days and had largely resolved by either 7 days or 1 month. CogSport testing at 2 days revealed cognitive impairments relative to both non-concussed peers and their own pre-injury baselines, with SRC classification utility found at 2 days, and to a slightly lesser extent, at 7 days. Relatively prolonged changes in serum NfL were observed, with elevated levels and classification utility persisting beyond the resolution of SRC symptoms and cognitive deficits. Finally, SRC classification performance throughout the 1st month after SRC was optimized through the combination of cognitive testing and serum biomarkers. Considered together, these findings provide further evidence for a role of computerized cognitive testing and fluid biomarkers of neuropathology as objective measures to assist in the identification of SRC and the monitoring of clinical and neuropathological recovery.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Recuperação de Função Fisiológica , Feminino , Humanos , Masculino , Traumatismos em Atletas/sangue , Traumatismos em Atletas/diagnóstico , Biomarcadores/sangue , Concussão Encefálica/sangue , Concussão Encefálica/diagnóstico , Projetos Piloto , Estudos Prospectivos
4.
Comput Biol Med ; 151(Pt B): 106327, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36442275

RESUMO

PURPOSE: Patients with mandibular defects due to trauma or infiltrated disease are in a need of functional mandibular implants that will completely restore the function of their lower jaw. One of the most important roles of well-functioning jaw is mastication, a complex mechanism. A conventional approach used in oral and maxillofacial surgery accomplish this aim via two major surgeries- mandibular reconstruction and surgical placement of dental implants. Little work has been done on combining the two surgeries into with using Additive Manufacturing (AM) and digital planning. MATERIAL AND METHODS: This case study offers a mandibular implant design solution with pre-positioned dental implants that can reduce the requirement to only one surgery. Mandibular implant was designed using 3-Matic software (Materialise, Belgium). Positions for dental implants were restoratively-driven and planned on the designed mandibular implant in Blue Sky Plan 4 software (Blue Sky Bio, USA) and placed prior to mandibular reconstruction using a 3D-printed surgical guide. Finite Element Analysis (FEA) was used to evaluate the mechanical behaviour of the 3D-printed surgical guide during dental implant placement. RESULTS: The surgical guide was fabricated using SLA and stress distribution was evaluated in ANSYS Workbench FEM software (Ansys Inc Swanson, Houston, USA). Results showed that the designed surgical guide can withstand the forces occurring during the surgery. CONCLUSION: The proposed method substantially reduces the surgical procedure and recovery time, increases the accuracy, and allows for a predictable restorative solution that can be visualised from the beginning.


Assuntos
Implantes Dentários , Reconstrução Mandibular , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Análise de Elementos Finitos , Impressão Tridimensional
5.
Atten Percept Psychophys ; 84(2): 383-395, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35178679

RESUMO

Research on the relationship between chronic stress and cognition is limited by a lack of concurrent measurement of state-anxiety, physiological arousal, and gender. For the first time, we assessed the impact of these factors on top-down/conscious (simple and choice reaction time) and bottom-up/reflexive (saccadic reaction time) measures of attention using CONVIRT virtual-reality cognitive tests. Participants (N = 163) completed measures of academic stress (effort-reward imbalance; ERI) and state-anxiety while heart-rate variability was recorded continuously throughout the experiment. Gender moderated the association between academic stress with the top-down measures (b = -0.002, t = -2.023, p = .045; b = -0.063, t = -3.080, p = .002) and higher academic stress was associated with poorer/slower reaction times only for male participants. For bottom-up attention, heart rate variability moderated the relationship between academic stress and saccadic reaction time (b = 0.092, t = 1.991, p = .048), and only female participants who were more stressed (i.e., ERI ≥ 1) and displayed stronger sympathetic dominance had slower reaction times. Our findings align with emerging evidence that chronic stress is related to hyperarousal in women and cognitive decrements in men. Our findings suggest that higher ERI and sympathetic dominance during cognitive testing was associated with poorer bottom-up attention in women, whereas for men, academic stress was related with poorer top-down attention irrespective of sympathovagal balance.


Assuntos
Ansiedade , Recompensa , Ansiedade/psicologia , Cognição/fisiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Tempo de Reação , Estresse Psicológico/psicologia
6.
Ergonomics ; 65(3): 445-466, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34487483

RESUMO

Tram drivers operate a master controller to control the acceleration and braking of the tram. Operation should ensure passenger comfort and safety through smooth tram motion and the avoidance of jerkiness that may cause passengers to fall in the carriage. This work investigates current driver practices and strategies for tram driving in normal operations through interviews and the capacity of a new haptic master controller to support drivers in achieving smooth and safe tram journeys. A haptic feedback algorithm based on viscosity was implemented on the master controller to provide drivers with feedback on the rate at which they were accelerating and braking the tram. This aspect was tested in a virtual tram within a simulated inner city virtual reality environment. Results indicate that the haptic master controller and coupled viscosity feedback algorithm did not increase smoothness of driving during the simulated experiences. Despite this, the drivers indicated a preference for the provision of further haptic information to support driving tasks and the overall journey safety and smoothness. Practitioner Summary: This research comprises two studies. The first investigates strategies currently used by drivers to operate a tram smoothly in order to elicit design requirements for a haptic tram master controller. The second study evaluates the impact of a novel haptic master controller on journey smoothness within a virtual environment.


Assuntos
Condução de Veículo , Realidade Virtual , Retroalimentação , Tecnologia Háptica , Humanos , Veículos Automotores , Interface Usuário-Computador
7.
Behav Res Methods ; 53(3): 1115-1123, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32989723

RESUMO

New technologies such as virtual reality (VR) and eye-tracking software have paved the way for more sophisticated and ecologically valid measures of cognitive function. Testing the sensitivity and reliability of such measurements in response to acute alcohol intoxication provides a first step in establishing how these measures may operate in relation to cognitive impairments observed post-concussion. Healthy young adults (N = 54, M = 20.65, SD = 2.06, 30 females) completed the CONVIRT test battery (manual simple and choice reaction-time and saccade reaction-time) at three breath alcohol concentration (BrAC) levels: 0.00%T1, 0.05%T2, 0.08%T3. Participants consumed alcoholic beverages at 30-min intervals, with BrAC monitored at 15-min intervals using a breathalyser. All three CONVIRT measures were sensitive to changes in cognitive performance induced by alcohol at BrAC levels at or exceeding 0.05%. A composite measure was also sensitive to alcohol intoxication (Cohen's d = .85 at BrAC = 0.05%; d = 1.20 at BrAC = 0.08%). Strong test-retest reliability was observed (all r < .80), with no gender differences noted. CONVIRT measures were reliable and detected dose-dependent changes in alcohol-induced cognitive impairment. Potentially, the ecologically valid measures may assist in better quantifying the effects of conditions such as concussion, on cognitive performance.


Assuntos
Concussão Encefálica , Disfunção Cognitiva , Realidade Virtual , Concussão Encefálica/diagnóstico , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Feminino , Humanos , Testes Neuropsicológicos , Reprodutibilidade dos Testes , Adulto Jovem
8.
Ann Biomed Eng ; 48(9): 2285-2300, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32691264

RESUMO

Mandibular and craniofacial bone defects can be caused by trauma, inflammatory disease, and benign or malignant tumors. Patients with bone defects suffer from problems with aesthetics, speech, and mastication, resulting in the need for implants. Conventional methods do not always provide satisfactory results. Most of the techniques proposed by researchers in the field of biomedical engineering use reverse engineering, computer-aided design (CAD), and additive manufacturing (AM), whose implementation can improve the outcomes of reconstructive surgeries. Several literature reviews on this particular topic have been conducted. However, they provide mostly overviews of AM technologies for general biomedical devices. This paper summarizes the use of existing medical AM techniques for the design and fabrication of mandibular and craniofacial implants, and then discusses their advantages and disadvantages in terms of accuracy, costs, energy consumption, and production rate. The aim of this study is to present a comparative review of the most commonly used AM technologies to aid researchers in selecting the best possible AM technologies for medical use. Studies included in this review contain CAD designs of mandibular or cranial implants, as well as their fabrication using AM technologies. Special attention is paid to PolyJet technology, because of its high accuracy, and economical efficiency.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Engenharia Biomédica , Ossos Faciais , Mandíbula , Traumatismos Mandibulares , Procedimentos de Cirurgia Plástica , Próteses e Implantes , Ossos Faciais/diagnóstico por imagem , Ossos Faciais/lesões , Ossos Faciais/cirurgia , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Traumatismos Mandibulares/diagnóstico por imagem , Traumatismos Mandibulares/cirurgia
9.
BMC Psychol ; 8(1): 61, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532362

RESUMO

BACKGROUND: Technological advances provide an opportunity to refine tools that assess central nervous system performance. This study aimed to assess the test-retest reliability and convergent and ecological validity of a newly developed, virtual-reality, concussion assessment tool, 'CONVIRT', which uses eye-tracking technology to assess visual processing speed, and manual reaction time (pushing a button on a riding crop) to assess attention and decision-making. CONVIRT was developed for horse jockeys, as of all sportspersons, they are most at risk of concussion. METHODS: Participants (N = 165), were assessed with CONVIRT, which uses virtual reality to give the user the experience of riding a horse during a horserace. Participants were also assessed with standard Cogstate computer-based concussion measures in-between two completions of the CONVIRT battery. The physiological arousal induced by the test batteries were assessed via measures of heart rate and heart rate variability (LF/HF ratio). RESULTS: Satisfactory test-retest reliability and convergent validity with Cogstate attention and decision-making subtests and divergent validity in visual processing speed measures were observed. CONVIRT also increased heart rate and LF/HF ratio, which may better approximate participant arousal levels in their workplace. CONCLUSIONS: CONVIRT may be a reliable and valid tool to assess elements of cognition and CNS disruption. The increased ecological validity may also mean better informed 'return-to-play' decisions and stronger industry acceptance due to the real-world meaningfulness of the assessment. However, before this can be achieved, the sensitivity of the CONVIRT battery needs to be demonstrated.


Assuntos
Cognição , Testes Neuropsicológicos , Realidade Virtual , Adolescente , Adulto , Atenção , Concussão Encefálica/diagnóstico , Cognição/fisiologia , Feminino , Humanos , Masculino , Tempo de Reação , Reprodutibilidade dos Testes , Adulto Jovem
10.
Sci Total Environ ; 689: 883-898, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31280170

RESUMO

Urban climate knowledge has been increasingly integrated into urban design and planning practices. Numerical modeling systems, such as climatic and bioclimatic tools, are currently more popular than onsite field measurements. This higher popularity is mainly due to the complicated interactions in 3D urban environments and the spatial distribution of various climatic parameters that cannot be captured thoroughly via on-site measurements alone. Such modeling systems also offer better solutions to overcome the nonlinearity of urban climate in forecasting different "what if scenarios." This paper provides an overview of different types of climatic and bioclimatic modeling systems and presents their main benefits and shortcomings. In the second part of this study, one of the most commonly used tools in urban climate studies, namely, ENVI-met, was selected, and its reliability in different contexts was investigated by reviewing past researches. The applicability of ENVI-met in accurately simulating the influence of future urban growth on one of the fastest growing suburbs in Melbourne, was tested by conducting a sensitivity analysis on inputs and control parameters, backed up with a series of field measurements in selected points. RMSE value was calculated for different runs of the initial ENVI-met model with adjusted control parameters (e.g., factor of short-wave adjustment, initial air temperature, relative humidity, roughness length, wind speed, albedo of walls, and albedo of roofs). The model achieved the optimum performance by altering the short-wave adjustment factor from 0.5 to 1; therefore, ENVI-met was considered a reliable tool for relative comparison of urban dynamics. The findings of this study not only help planners select the most practical modeling systems that address project objectives but also educate them on limitations associated with using ENVI-met.


Assuntos
Clima , Monitoramento Ambiental/métodos , Meteorologia/métodos , Cidades , Modelos Teóricos , Reprodutibilidade dos Testes , Vitória
11.
Physiol Behav ; 199: 292-299, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30503848

RESUMO

The job demands-resources model (JD-R) has shown an ability to predict worker engagement and exhaustion, yet to our knowledge, research has not been conducted that assesses the JD-R model with physiological indicators of chronic stress and burnout. Using the JD-R model, we assessed if occupational stress and burnout were related to dysregulated cortisol and salivary alpha-amylase awakening responses (sAA-AR). Professional apprentice jockeys comprising of males (n = 14) and females (n = 18) provided morning saliva samples and completed self-report measures relating to job demands and resources, burnout, and perceived mental and physical health. Data was collected at two time points coinciding with naturally occurring 'low' and 'high' stress periods during the racing calendar. The jockeys reported good physical and mental health but had elevated levels of the burnout subtypes cynicism and exhaustion. Regression analyses suggested that those jockeys presenting with reduced professional efficacy in the high stress period produced a 'flattened' sAA-AR indicative of reduced autonomic nervous system (ANS) arousal, which has been associated with burnout. Further, decreases in professional efficacy explained the relationship between increased workplace stress and decreased ANS activity in the high stress period. Our findings suggest that assessments of psychological stress or physiology in isolation are not as useful as looking at both in combination, and extend previous findings on the sAA-AR.


Assuntos
Esgotamento Profissional/diagnóstico , Hidrocortisona/análise , alfa-Amilases Salivares/análise , Estresse Psicológico/diagnóstico , Adolescente , Esgotamento Profissional/fisiopatologia , Feminino , Humanos , Masculino , Saúde Mental , Saliva/química , Estresse Psicológico/fisiopatologia , Local de Trabalho , Adulto Jovem
12.
PLoS One ; 13(4): e0193772, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29702645

RESUMO

In this paper, the suitability and performance of ANFIS (adaptive neuro-fuzzy inference system), ANFIS-PSO (particle swarm optimization), ANFIS-GA (genetic algorithm) and ANFIS-DE (differential evolution) has been investigated for the prediction of monthly and weekly wind power density (WPD) of four different locations named Mersing, Kuala Terengganu, Pulau Langkawi and Bayan Lepas all in Malaysia. For this aim, standalone ANFIS, ANFIS-PSO, ANFIS-GA and ANFIS-DE prediction algorithm are developed in MATLAB platform. The performance of the proposed hybrid ANFIS models is determined by computing different statistical parameters such as mean absolute bias error (MABE), mean absolute percentage error (MAPE), root mean square error (RMSE) and coefficient of determination (R2). The results obtained from ANFIS-PSO and ANFIS-GA enjoy higher performance and accuracy than other models, and they can be suggested for practical application to predict monthly and weekly mean wind power density. Besides, the capability of the proposed hybrid ANFIS models is examined to predict the wind data for the locations where measured wind data are not available, and the results are compared with the measured wind data from nearby stations.


Assuntos
Modelos Teóricos , Energia Renovável , Vento , Algoritmos , Lógica Fuzzy , Malásia
13.
Psychoneuroendocrinology ; 84: 151-158, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28732265

RESUMO

The inverse relationship between acute stress and decision-making is well documented, but few studies have investigated the impact of chronic stress. Jockeys work exhaustive schedules and have extremely dangerous occupations, with safe performance requiring quick reaction time and accurate decision-making. We used the effort reward imbalance (ERI) occupational stress model to assess the relationship of work stress with indices of stress physiology and decision-making and reaction time. Jockeys (N=32) completed computerised cognitive tasks (Cogstate) on two occasions; September and November (naturally occurring lower and higher stress periods), either side of an acute stress test. Higher ERI was correlated with the cortisol awakening responses (high stress r=-0.37; low stress r=0.36), and with decrements in decision-making comparable to having a blood alcohol concentration of 0.08 in the high stress period (p<0.001) The LF/HF ratio of heart rate variability impacted the association of ERI with decision-making. Potentially, this may be attributed to a 'tipping point' whereby the higher ERI reported by jockeys in the high stress period decreases vagal tone, which may contribute to reduced decision-making abilities.


Assuntos
Tomada de Decisões/fisiologia , Estresse Ocupacional/psicologia , Tempo de Reação/fisiologia , Adolescente , Atletas/psicologia , Concentração Alcoólica no Sangue , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hidrocortisona/análise , Masculino , Ocupações , Recompensa , Estresse Psicológico/fisiopatologia , Nervo Vago/fisiologia , Trabalho/psicologia , Adulto Jovem
14.
Sensors (Basel) ; 17(3)2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28335431

RESUMO

The Robot Operating System (ROS) provides roboticists with a standardized and distributed framework for real-time communication between robotic systems using a microkernel environment. This paper looks at how ROS metadata, Unified Robot Description Format (URDF), Semantic Robot Description Format (SRDF), and its message description language, can be used to identify key robot characteristics to inform User Interface (UI) design for the teleoperation of heterogeneous robot teams. Logical relationships between UI components and robot characteristics are defined by a set of relationship rules created using relevant and available information including developer expertise and ROS metadata. This provides a significant opportunity to move towards a rule-driven approach for generating the designs of teleoperation UIs; in particular the reduction of the number of different UI configurations required to teleoperate each individual robot within a heterogeneous robot team. This approach is based on using an underlying rule set identifying robots that can be teleoperated using the same UI configuration due to having the same or similar robot characteristics. Aside from reducing the number of different UI configurations an operator needs to be familiar with, this approach also supports consistency in UI configurations when a teleoperator is periodically switching between different robots. To achieve this aim, a Matlab toolbox is developed providing users with the ability to define rules specifying the relationship between robot characteristics and UI components. Once rules are defined, selections that best describe the characteristics of the robot type within a particular heterogeneous robot team can be made. A main advantage of this approach is that rather than specifying discrete robots comprising the team, the user can specify characteristics of the team more generally allowing the system to deal with slight variations that may occur in the future. In fact, by using the defined relationship rules and characteristic selections, the toolbox can automatically identify a reduced set of UI configurations required to control possible robot team configurations, as opposed to the traditional ad-hoc approach to teleoperation UI design. In the results section, three test cases are presented to demonstrate how the selection of different robot characteristics builds a number of robot characteristic combinations, and how the relationship rules are used to determine a reduced set of required UI configurations needed to control each individual robot in the robot team.

15.
IEEE Trans Haptics ; 6(1): 46-57, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24808267

RESUMO

Virtual reality and simulation are becoming increasingly important in modern society and it is essential to improve our understanding of system usability and efficacy from the users' perspective. This paper introduces a novel evaluation method designed to assess human user capability when undertaking technical and procedural training using virtual training systems. The evaluation method falls under the user-centered design and evaluation paradigm and draws on theories of cognitive, skill-based and affective learning outcomes. The method focuses on user interaction with haptic-audio-visual interfaces and the complexities related to variability in users' performance, and the adoption and acceptance of the technologies. A large scale user study focusing on object assembly training tasks involving selecting, rotating, releasing, inserting, and manipulating three-dimensional objects was performed. The study demonstrated the advantages of the method in obtaining valuable multimodal information for accurate and comprehensive evaluation of virtual training system efficacy. The study investigated how well users learn, perform, adapt to, and perceive the virtual training. The results of the study revealed valuable aspects of the design and evaluation of virtual training systems contributing to an improved understanding of more usable virtual training systems.


Assuntos
Percepção Auditiva/fisiologia , Percepção do Tato/fisiologia , Interface Usuário-Computador , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Software , Adulto Jovem
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