Search

Driver characteristics have been linked to the frequency and severity of car crashes. Among these, age and gender have been shown to impact both the possibility and severity of a crash. Previous studies have used standard ordered probit (OP) models to analyze crash data, and some research has suggested heteroskedastic ordered probit (HETOP) could provide improved model fit. The objective of this paper is to evaluate potential improvements of the heteroskedastic ordered probit (HETOP) model compared to the standard ordered probit (OP) model in crash analysis, by examining the effect of gender across age on injury severity among drivers. This paper hypothesizes that the HETOP model can provide a better fit to crash data, by allowing heteroskedasticity in the distribution of injury severity across driver age and gender. Data for 20,222 crashes were analyzed for North Carolina from 2016 to 2018, which represents the state with the highest number of fatalities per 100 million vehicle miles traveled amongst available crash data from the Highway Safety Information System. Darker lighting conditions, severe road surface conditions, and less severe weather were associated with increased injury severity. For driver demographics, the probability of severe injuries increased with age and for male drivers. Moreover, the variance of severity increased with age disproportionately within and across genders, and the HETOP was able to account for this. The results of the two applied approaches revealed that HETOP model outperformed the standard OP model when measuring the effects of age and gender together in injury severity analysis, due to the heteroskedasticity in injury severity within gender and age. The HETOP statistical method presented in this paper can be more broadly applied across other contexts and combinations of independent variables for improved model prediction and accuracy of causal variables in traffic safety. [ABSTRACT FROM AUTHOR]

The adoption of agricultural machinery in countries with a developing economy can have a significant impact on improving well-being and pro-poor growth. However, this requires farmers to buy into mechanized farming, which is more likely to happen if the machinery meets their needs. The objective of this paper is to identify deciding factors for traditional farmers to adopt machinery and identify design requirements. Payback models were developed based on these design requirements, willingness to pay, and expected returns. Thirty-six farmers in Sudan were interviewed throughout 2019–2021. Six of these farmers were provided tractors during 2020 and 2021. Differences in net-profits between the 30 control and 6 treatment farms during the mechanized farming seasons were used in the models for expected profits. There were no significant differences in tractor design preferences between the treatment and control groups. Two cost models were estimated using a 95% confidence interval: entire Δ profit (entire additional profit from mechanized farming above nonmechanized) and percentage of total profit (percentage of total net-profits willing to spend). For the average farm size in this study (44.39 acres) and a market available tractor that satisfied all farmer needs, payback was 3.92 years [2.34, 8.54] and 4.57 years [3.39, 6.38] for the models, respectively. [ABSTRACT FROM AUTHOR]

The study evaluated the connectedness of spontaneous speech production in individuals with dementia as a potential predictor of dementia severity. Data were derived from the baseline sample of 143 individuals with dementia in the English Pitt corpus. Dementia severity was assessed via the Mini Mental Status Exam, the Mattis Dementia Rating Scale, and the Blessed Dementia Scale. Language abilities were evaluated using verbal fluency and picture description tasks. Graph analysis was carried out for the picture description task using the computational tool SpeechGraphs to calculate connectedness. Results demonstrated that higher educational attainment, higher verbal fluency and strongly-connected spontaneous speech were associated with better cognitive function. Results suggest that automated language processing approaches, such as graph structure analysis, may provide a faster and ecologically valid method of detecting dementia symptoms. [ABSTRACT FROM AUTHOR]

Drivers with a Commercial Driver's License (CDL) experience higher rates of fatal and serious injury crashes compared to non-commercial drivers. Emotional Intelligence (EI) has shown to be a significant predictor of dangerous driving among non-commercial drivers. However, there is limited research investigating EI within commercial drivers. This paper investigates the relationship between drivers' EI and dangerous driving behaviors, and how this differs between commercial (N = 595) and non-commercial (N = 615) drivers. A survey was conducted, where EI was measured using Trait Emotional Intelligence Questionnaire, and risky driving using Dula Dangerous Driving Questionnaire. Analyses confirmed (1) commercial drivers have lower EI than non-commercial (ANCOVA, p <.01); (2) commercial drivers are more likely to report more dangerous driving behaviors (MANCOVA, p <.01); and (3) lower EI is associated with increased dangerous driving, and these effects are strongest amongst commercial drivers (linear regression, p <.001). Promoting and improving EI can help prevent dangerous driving and reduce crash risk. [ABSTRACT FROM AUTHOR]

This article explores mental models on obsolescence management to assist with mitigating obsolescence for Command, Control, Computers, Communications, Cyber, Intelligence, Surveillance, and Reconnaissance (C5ISR) systems. A systems-thinking methodology was used to develop these mental models, which were validated through interviews with 10 participants. The participants were U.S. Army acquisition practitioners at Aberdeen Proving Ground, Maryland. This research complements the tools and training for mitigating obsolescence by deepening an organization’s understanding of the relationships among systems and the mental models that influence obsolescence management. These mental models are foundational to the interaction relationships of the system of interest (Diminishing Manufacturing Sources and Material Shortages, or DMSMS Management System) within the context of engineered systems. This is enabled by supporting systems such as the supply chain, configuration management, and the budget. Furthermore, this research presents a novel model of the systems within the obsolescence management system. Based on the relationships in the causal loop diagrams and application of a risk-based proactive obsolescence management mental model, one can predict a higher or lower likelihood of successfully mitigating a C5ISR system’s obsolescence. [ABSTRACT FROM AUTHOR]

The adoption of agricultural technologies in developing economy countries has the potential to reduce poverty through sustainable intensification. Mechanized farming can also improve perceptions of farming and mitigate rural out-migration. However, many traditional farmers do not have access to machinery and/or machinery is cost prohibitive. The objective of this paper is to quantify how the use of machinery affects costs, revenue, net-profits, and returns on investment for a case study of farmers in Sudan, Africa. A treatment control study (N = 36) was performed across the 2019 (baseline), 2020, and 2021 farming seasons, where the treatment group was provided tractors. ANOVAs and t-tests were used to compare financial values between these groups across the farming seasons, to quantify economic differences associated with farming machinery. We show that all farmers had similar net-profits when farming without machinery, while mechanized farming yielded significantly higher net-profits (USD 16.61/acre more in 2020, USD 27.10/acre more in 2021). Our study also finds that the volatility of the black-market exchange rate and labor shortages have a significant impact on farming net-profits. These results provide a quantified difference between farming with and without machinery, which can provide a financial basis for purchasing and borrowing models, machinery design requirements, and educational value to farmers. [ABSTRACT FROM AUTHOR]

Shared electric scooters (e-scooters) offer a potential strategy to mitigate environmental concerns and congestion. However, successfully addressing these issues with e-scooters requires adoption across a diverse array of consumers. Understanding the differences between users and non-users can improve shared e-scooter appeal, operation and safety. The objective of this paper is to compare shared e-scooter users and non-users in terms of their perceptions on safety, trip behaviors, other shared modes, risk propensity and willingness to adopt technology. A survey was conducted involving 210 (51.3%) users and 199 (48.7%) non-users of shared e-scooters. Binary logistic regression and chi-squared tests were performed. The results reveal that users demonstrated a higher risk propensity and were more likely to be early adopters of new technologies. Non-users tended to place higher importance on helmet use, while users have an overall increased feeling of safety associated with riding e-scooters in vehicle lanes, on sidewalks and being passed by e-scooters as a pedestrian. Overall, users also have a more positive perception of e-scooter sanitary levels than non-users, and a more positive perception on the sanitary levels and usability of e-scooters over e-bicycles. These findings can provide guidance to urban planners, municipal authorities and micromobility providers in developing infrastructure and policies to better support micromobility adoption. [ABSTRACT FROM AUTHOR]

Obsolescence is a significant challenge for the Command, Control, Communications, Computers, Cyber, Intelligence, Surveillance and Reconnaissance (C5ISR) community. Obsolescence can negatively affect a C5ISR system’s cost, schedule, performance, and readiness. This article examines the challenge of obsolescence for C5ISR systems by focusing on the U.S. Army at Aberdeen Proving Ground, Maryland, and their industry partners. Data were gathered by conducting interviews with 20 individuals who had experience with C5ISR systems: 10 government Army civilians and 10 industry partner employees. The objective of this study is to synthesize insights from the experiences of government and industry practitioners that mitigate diminishing manufacturing sources and material shortages (DMSMS) challenges. The obsolescence mitigation areas described in this article include proactive and reactive obsolescence mitigation, obsolescence mitigation methods, opportunities for alternative components and planned improvements, the importance of DMSMS contracting language, and obsolescence management practices to avoid. This article also offers approaches grounded in practitioner experiences to mitigate obsolescence through a preliminary proactive obsolescence management model, risk mitigation framework, and metrics. The combination of the obsolescence mitigation approaches discussed in this article has the potential to achieve greater system readiness, more availability, better maintainability, and lower costs for C5ISR systems. [ABSTRACT FROM AUTHOR]

This study aims to identify expectations and perceptions of Passenger Air Vehicles (PAVs). Specifically, (1) what are the initial perceptions of PAVs by the public, and (2) what are the differences between early and laggard adopters of PAVs. The emergence of Urban Air Mobility presents an opportunity to increase transportation capacity in densely populated metropolitan areas. However, successful integration is largely dependent on adoption and acceptance from communities. A survey of 407 respondents across the United States provides insights from potential users. The Technology Adoption Life Cycle and Technology Acceptance Model are used to characterize adopter profiles and rates of adoption. Respondents not only expect the same level of safety standards as conventional aircraft (i.e., seatbelts, air quality), but even more feedback (i.e., displays on current and projected flight operations). PAVs are not an immediate replacement for daily trips once available. In-cabin noise is not a crucial deterrent to ridership. Earlier PAV adopters are trusting of the technology, willing to pay more to ride, and exhibit overall riskier behaviors. Later PAV adopters need more feedback in-flight and a pilot on-board. PAV manufacturers, operators, and policymakers can utilize these findings to incorporate crucial design elements needed for PAVs to satisfy user expectations. These findings identify priorities that should be targeted in relative timeframes to satisfy near-term and long-term PAV users appropriately. [ABSTRACT FROM AUTHOR]

Widespread adoption of agricultural machinery for developing economy countries is commonly regarded as a fundamental component of pro-poor growth. This study evaluates agricultural practices using a Human-Systems Integration approach to more effectively adapt technologies to satisfy farmers' needs. Six farms in Sudan, Africa were surveyed regarding their opinions towards using farming machinery, were then provided a tractor, and surveyed again after using the tractor for the planting season. The largest barriers for adoption were culture, security, and maintenance costs. However, the biggest challenges of their current practices were related to labor, safety, and profit margins; all of which could be addressed with machinery. Despite the initial resistance, all of the farmers were satisfied by their experience and expressed an even more accepting attitude from their children. [ABSTRACT FROM AUTHOR]

Widespread adoption of agricultural machinery for developing economy countries is commonly regarded as a fundamental component of pro‐poor growth. This study evaluates agricultural practices using a Human‐Systems Integration approach to more effectively adapt technologies to satisfy farmers' needs. Six farms in Sudan, Africa were surveyed regarding their opinions towards using farming machinery, were then provided a tractor, and surveyed again after using the tractor for the planting season. The largest barriers for adoption were culture, security, and maintenance costs. However, the biggest challenges of their current practices were related to labor, safety, and profit margins; all of which could be addressed with machinery. Despite the initial resistance, all of the farmers were satisfied by their experience and expressed an even more accepting attitude from their children. [ABSTRACT FROM AUTHOR]

The article presents a cross-cultural study of take-over performance in highly automated driving. As take-over performance is an important measure of safe driving, potential cultural differences could have important implications for the future development of automated vehicles. The study was conducted in two culturally different locations, Seattle, WA (n = 20) and Ljubljana, Slovenia (n = 18), using a driving simulator. While driving, participants voluntarily engaged in secondary tasks. The take-over request (TOR) was triggered at a specific time during the drive, and take-over time and type of response (none, brake, steer) were measured for each participant. Results show significant differences in take-over performance between the two locations. In Seattle 30% of participants in Seattle did not respond to TOR; the remaining 70% responded by braking only, compared to Slovenian participants who all responded by either braking or steering. Participants from Seattle responded significantly more slowly to TOR (M = +1285 ms) than Slovenian participants. Secondary task engagement at TOR also had an effect, with distracted US participants' response taking significantly longer (M = +1596 ms) than Slovenian participants. Reported differences in take-over performance may indicate cultural differences in driving behavior and trust in automated driving. [ABSTRACT FROM AUTHOR]

Objective: Automated Truck-Mounted Attenuators (ATMAs) have the potential to improve work zone safety by removing the human driver out of a vehicle that is positioned in work zones to absorb impact from errant vehicles. However, this automated technology is expensive and can be detrimental to safety and project success if operated incorrectly (e.g., operating limitations and procedures not followed). Therefore, it is important to understand users' perceptions of ATMAs and how training can improve appropriate adoption of this technology. The objective of this study was to evaluate how work zone workers perceive the usefulness of and the capabilities of automation in Truck-Mounted Attenuators.Methods: A survey study was conducted with 13 Department of Transportation (DOT) workers in Colorado and California. Each of the DOT workers in this study had some previous experience with the ATMA, either in real-world applications and/or formal training. The survey collected information on participant job specifications, experience with the ATMA, training received, trust in the ATMA, usability of the HMIs, and operating capabilities of the automation.Results: Workers reported an overall positive acceptance of this technology. This was supported by their expectation that it would reduce crash severity; that there was a reasonable workload associated with operating procedures for the automation; and by their overall trust in the automation's reliability. However, workers noted concerns regarding their trust in the automation under various contexts, such as poor visibility and denser traffic volumes. Further, trust in the technology was greatest among workers with higher levels of ATMA training and longer experience working with the ATMA.Conclusions: This research presents a novel perspective on user acceptance of ATMA technology. These findings can help jurisdictions achieve the safety improvements that investment and deployment of automation in work zones offers, by identifying the disconnect between operators and technology. [ABSTRACT FROM AUTHOR]

Objective: A driving simulator study was conducted to evaluate the longitudinal effects of an intervention and withdrawal of a lane keeping system on driving performance and cognitive workload.Background: Autonomous vehicle systems are being implemented into the vehicle fleet. However, limited research exists in understanding the carryover effects of long-term exposure.Methods: Forty-eight participants (30 treatment, 18 control) completed eight drives across three separate days in a driving simulator. The treatment group had an intervention and withdrawal of a lane keeping system. Changes in driving performance (standard deviation of lateral position [SDLP] and mean time to collision [TTC]) and cognitive workload (response time and miss rate to a detection response task) were modeled using mixed effects linear and negative binomial regression.Results: Drivers exposed to the lane keeping system had an increase in SDLP after the system was withdrawn relative to their baseline. Drivers with lane keeping had decreased mean TTC during and after system withdrawal compared with manual drivers. There was an increase in cognitive workload when the lane keeping system was withdrawn relative to when the system was engaged.Conclusion: Behavioral adaptations in driving performance and cognitive workload were present during automation and persisted after the automation was withdrawn.Application: The findings of this research emphasize the importance to consider the effects of skill atrophy and misplaced trust due to semi-autonomous vehicle systems. Designers and policymakers can utilize this for system alerts and training. [ABSTRACT FROM AUTHOR]

State licensure procedures for PAs (physician assistants) vary significantly, as does the average time necessary for states to process a PA license. This article discusses these variations and presents evidence that states with the highest number of extra requirements for PA licensure tend to have longer license processing times. It also includes an analysis showing that states with modernized PA practice laws (e.g., laws that allow PAs to practice to the full extent of their education and experience) tend to have fewer extra licensure requirements. Finally, this article discusses potential benefits of reducing extra PA licensure requirements, including mitigation of health care practitioner shortages without compromising patient safety and greater adoption of the Uniform Application (UA) for PAs. [ABSTRACT FROM AUTHOR]

The goal of this educational outreach project was to examine perceptions of driver distraction among teenagers in the Pacific Northwest. Specifically, to identify secondary tasks this group may consider distracting and determine their self-reported engagement in those same secondary tasks while driving. An interactive presentation was developed and administered to 1,400 teenage drivers. Teenagers from age 14 to 18 years were recruited from high schools in Washington, Idaho, and Oregon with an approximately equal sample in each State. Of these participants, 1,006 teenage drivers responded to a pre- and postknowledge survey administered immediately before and 2 weeks after the interactive presentation. The purpose of the survey was to measure the degree to which the interactive presentation improved teenage driver perspectives regarding the hazards of distracted driving. Results indicated that the interactive presentation positively influenced teenage driver perspectives, meaning that after the interactive presentation, teenage drivers were more likely to correctly identify different types of distracted driving. [ABSTRACT FROM AUTHOR]