471 research outputs found
Towards a Smart World: Hazard Levels for Monitoring of Autonomous Vehicles’ Swarms
This work explores the creation of quantifiable indices to monitor the safe operations and movement of families of autonomous vehicles (AV) in restricted highway-like environments. Specifically, this work will explore the creation of ad-hoc rules for monitoring lateral and longitudinal movement of multiple AVs based on behavior that mimics swarm and flock movement (or particle swarm motion). This exploratory work is sponsored by the Emerging Leader Seed grant program of the Mineta Transportation Institute and aims at investigating feasibility of adaptation of particle swarm motion to control families of autonomous vehicles. Specifically, it explores how particle swarm approaches can be augmented by setting safety thresholds and fail-safe mechanisms to avoid collisions in off-nominal situations. This concept leverages the integration of the notion of hazard and danger levels (i.e., measures of the “closeness” to a given accident scenario, typically used in robotics) with the concept of safety distance and separation/collision avoidance for ground vehicles. A draft of implementation of four hazard level functions indicates that safety thresholds can be set up to autonomously trigger lateral and longitudinal motion control based on three main rules respectively based on speed, heading, and braking distance to steer the vehicle and maintain separation/avoid collisions in families of autonomous vehicles. The concepts here presented can be used to set up a high-level framework for developing artificial intelligence algorithms that can serve as back-up to standard machine learning approaches for control and steering of autonomous vehicles. Although there are no constraints on the concept’s implementation, it is expected that this work would be most relevant for highly-automated Level 4 and Level 5 vehicles, capable of communicating with each other and in the presence of a monitoring ground control center for the operations of the swarm
Analysis of Disengagements in Semi-Autonomous Vehicles: Drivers’ Takeover Performance and Operational Implications
This report analyzes the reactions of human drivers placed in simulated Autonomous Technology disengagement scenarios. The study was executed in a human-in-the-loop setting, within a high-fidelity integrated car simulator capable of handling both manual and autonomous driving. A population of 40 individuals was tested, with metrics for control takeover quantification given by: i) response times (considering inputs of steering, throttle, and braking); ii) vehicle drift from the lane centerline after takeover as well as overall (integral) drift over an S-turn curve compared to a baseline obtained in manual driving; and iii) accuracy metrics to quantify human factors associated with the simulation experiment. Independent variables considered for the study were the age of the driver, the speed at the time of disengagement, and the time at which the disengagement occurred (i.e., how long automation was engaged for). The study shows that changes in the vehicle speed significantly affect all the variables investigated, pointing to the importance of setting up thresholds for maximum operational speed of vehicles driven in autonomous mode when the human driver serves as back-up. The results shows that the establishment of an operational threshold could reduce the maximum drift and lead to better control during takeover, perhaps warranting a lower speed limit than conventional vehicles. With regards to the age variable, neither the response times analysis nor the drift analysis provide support for any claim to limit the age of drivers of semi-autonomous vehicles
The Effect of Landscape Architecture on Climate Change
Permanent environmental influences such as sun, fog, acid rain can destroy structures, buildings and the environment. Improving the quality of urban environment with utilizing green roof and green facades is illustrated for several years and installing them can offer multiple benefits. A detailed integrated presentation of green roof and green facade systems is provided in this paper. The aim of the research is to illustrate the effect of green façade and green roofs and generally greenery structure on the climate changes. The author tries to find a solution for the climate changes and environmental issues and resolving it by above- mentioned landscape architecture methods
Developing a measure of blind patients\u27 interactions with their healthcare providers
Background: People who are blind (PWB) are often perceived as being incompetent with common tasks and functions. When patients detect that their healthcare providers (HCPs) have negative perceptions of them, they often report less satisfaction with their healthcare and disengage in their own healthcare.
Objective: A scale assessing the experiences of PWB interacting with HCPs was developed and validated across two studies.
Methods: In Study 1, 144 participants completed the scale and provided feedback. In Study 2, 214 participants completed the scale and 4 additional scales to assess construct validity.
Results: An exploratory factor analysis in Study 1 revealed a two-factor model consisting of General Quality of Health Care (30.5% variance explained) and Stereotype Content-related items (9.4% variance explained). Study 2 confirmed and validated this two-factor structure (RMSEA (90% CI) = 0.068 (0.057, 0.079), CFI = 0.898, SRMR = 0.066, AIC = 14568.902).
Conclusions: This scale is one of the first tools developed from the perspectives of PWB. Results from these studies highlight and elaborate on how PWB perceive that they are viewed by their HCPs in terms of competence and how they perceive to be treated by these HCPs. This scale can be used in training HCPs to better serve their patients with disabilities
The underrepresentation of Latinx students in the professional dissemination of psychology research
Latinx students are well represented among undergraduate psychology majors. However, there is an underrepresentation of Latinxs in psychology graduate programs, among faculty, and licensed practitioners. This underrepresentation is evidence of a leaky pipeline of attrition among Latinx psychology students from bachelor to postbachelor career tracks. The present research investigates one point of this leaky pipeline—research activity and professional dissemination of research. We used public data sets and surname matching to compare Latinx student representation at a regional psychology conference to Latinx enrollment and psychology degree completions at colleges and universities represented at the conference. We found consistent evidence of Latinx underrepresentation in the professional dissemination of research. This underrepresentation occurred at both federally designated Hispanic-serving institutions (HSIs) and non-HSIs. This research shows one point in the academic pipeline in psychological science at which Latinx students are underrepresented. Results provide evidence for a lack of recruitment of Latinx students into the research process. This disparity in research activity may lead to attrition from undergraduate to postbachelor education and career tracks in psychology. Strategies that faculty and departments can employ to address these disparities are discussed
Sound quality effects of an adaptive nonlinear frequency compression processor with normal-hearing and hearing-impaired listeners
© 2019 American Academy of Audiology. All rights reserved. Background: Frequency lowering (FL) technology offers a means of improving audibility of high-frequency sounds. For some listeners, the benefit of such technology can be accompanied by a perceived degradation in sound quality, depending on the strength of the FL setting. Purpose: The studies presented in this article investigate the effect of a new type of FL signal processing for hearing aids, adaptive nonlinear frequency compression (ANFC), on subjective speech quality. Research Design: Listener ratings of sound quality were collected for speech stimuli processed with systematically varied fitting parameters. Study Sample: Study 1 included 40 normal-hearing (NH) adult and child listeners. Study 2 included 11 hearing-impaired (HI) adult and child listeners. HI listeners were fitted with laboratory-worn hearing aids for use during listening tasks. Intervention: Speech quality ratings were assessed across test conditions consisting of various strengths of static nonlinear frequency compression (NFC) and ANFC speech. Test conditions included those that were fine-tuned on an individual basis per hearing aid fitting and conditions that were modified to intentionally alter the sound quality of the signal. Data Collection and Analysis: Listeners rated speech quality using the MUlti Stimulus test with Hidden Reference and Anchor (MUSHRA) test paradigm. Ratings were analyzed for reliability and to compare results across conditions. Results: Results show that interrater reliability is high for both studies, indicating that NH and HI listeners from both adult and child age groups can reliably complete the MUSHRA task. Results comparing sound quality ratings across experimental conditions suggest that both the NH and HI listener groups rate the stimuli intended to have poor sound quality (e.g., anchors and the strongest available parameter settings) as having below-average sound quality ratings. A different trend in the results is reported when considering the other experimental conditions across the listener groups in the studies. Speech quality ratings measured with NH listeners improve as the strength of ANFC decreases, with a range of bad to good ratings reported, on average. Speech quality ratings measured with HI listeners are similar and above-average for many of the experimental stimuli, including those with fine-tuned NFC and ANFC parameters. Conclusions: Overall, HI listeners provide similar sound quality ratings when comparing static and adaptive forms of frequency compression, especially when considering the individualized parameter settings. These findings suggest that a range in settings may result in above-average sound quality for adults and children with hearing impairment. Furthermore, the fitter should fine-tune FL parameters for each individual listener, regardless of type of FL technology
Development and Validation of a Measure for Seeking Health Information in the Diabetes Online Community: Mixed Methods Study
Background
Individuals with chronic diseases often search for health information online. The Diabetes Online Community (DOC) is an active community with members who exchange health information; however, few studies have examined health information brokering in the DOC. Objective
The aim of this study was to develop and validate the Attitudes Toward Seeking Health Information Online (ATSHIO) scale in a sample of adults with type 1 diabetes (T1D). Methods
People with T1D were recruited through the DOC, specifically Facebook and Twitter. They were provided with a Qualtrics link to complete the survey. This was a mixed methods study that used thematic analysis along with existing theory and formative research to design the quantitative ATSHIO scale. Results
A total of 166 people with T1D participated in this study. Confirmatory factor analyses determined a 2-factor scale (Trusting and Evaluating Online Health Information in the DOC and Engaging With Online Health Information in the DOC) with good convergent validity and discriminant validity. Correlations were found between social support, online health information–seeking, diabetes distress, and disease management. Conclusions
The ATSHIO scale can be used to investigate how people with diabetes are using the internet for obtaining health information, which is especially relevant in the age of telehealth and Health 2.0
A randomised controlled trial investigating the benefits of adaptive working memory training for working memory capacity and attentional control in high worriers
The process of worry has been associated with reductions in working memory capacity and availability of resources necessary for efficient attentional control. This, in turn, can lead to escalating worry. Recent investigations into working memory training have shown improvements in attentional control and cognitive performance in high trait-anxious individuals and individuals with sub-clinical depression. The current randomised controlled trial investigated the effects of 15 days of adaptive n-back working memory training, or an active control task, on working memory capacity, attentional control and worry in a sample of high worriers. Pre-training, post-training and one-month follow-up measures of working memory capacity were assessed using a Change Detection task, while a Flanker task was used to assess attentional control. A breathing focus task was used as a behavioural measure of worry in addition to a number of self-report assessments of worry and anxiety. Overall there was no difference between the active training and the active control condition with both groups demonstrating similar improvements in working memory capacity and worry, post-training and at follow-up. However, training-related improvements on the n-back task were associated with gains in working memory capacity and reductions in worry symptoms in the active training condition. These results highlight the need for further research investigating the role of individual differences in working memory training
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