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Research on task performance under visual field loss is often limited due to small and heterogenous samples. Simulations of visual impairments hold the potential to account for many of those challenges. Digitally altered pictures, glasses, and contact lenses with partial occlusions have been used in the past. One of the most promising methods is the use of a gaze-contingent display that occludes parts of the visual field according to the current gaze position. In this study, the gaze-contingent paradigm was implemented in a static driving simulator to simulate visual field loss and to evaluate parallels in the resulting driving and gaze behavior in comparison to patients.

The sample comprised 15 participants without visual impairment. All the subjects performed three drives: with full vision, simulated left-sided homonymous hemianopia, and simulated right-sided homonymous hemianopia, respectively. During each drive, the participants drove through an urban environment where they had to maneuver through intersections by crossing straight ahead, turning left, and turning right.

The subjects reported reduced safety and increased workload levels during simulated visual field loss, which was reflected in reduced lane position stability and greater absence of large gaze movements. Initial compensatory strategies could be found concerning a dislocated gaze position and a distorted fixation ratio toward the blind side, which was more pronounced for right-sided visual field loss. During left-sided visual field loss, the participants showed a smaller horizontal range of gaze positions, longer fixation durations, and smaller saccadic amplitudes compared to right-sided homonymous hemianopia and, more distinctively, compared to normal vision.

The results largely mirror reports from driving and visual search tasks under simulated and pathological homonymous hemianopia concerning driving and scanning challenges, initially adopted compensatory strategies, and driving safety. This supports the notion that gaze-contingent displays can be a useful addendum to driving simulator research with visual impairments if the results are interpreted considering methodological limitations and inherent differences to the pathological impairment.

 

One dimension of the emerging politics of connected and automated vehicles (CAVs) is the development of public concerns over their societal implications and associated policy issues. This study uses original survey data from the United States to contribute to the anticipation of future policy and political issues for CAVs. Several studies have surveyed the public regarding CAVs; however, there are few studies that highlight the multidimensional public concerns that CAVs will most likely bring. The study breaks down the concept of “public” by showing that the demographic variables of gender, age, race, ethnicity, income, location (rural, suburban, urban), and political ideology (conservative, moderate, liberal) are significantly associated with three of the most salient public concerns to date (safety, privacy, and data security). Furthermore, the effects of demographic variables also vary across the type of policy issue. For example, women tend to be more concerned about safety than their male counterparts, and Hispanics (Latinx) tend to be more concerned about privacy than non-Hispanics. The research shows how the social scientific analysis of the “politics” of CAVs will require attention to the variegated connections between different types of public concern and different demographic variables.

 

We propose a reference architecture of safety-critical or industry-critical human cyber-physical systems (CPSs) capable of expressing essential classes of system-level interactions between CPS and humans relevant for the societal acceptance of such systems. To reach this quality gate, the expressivity of the model must go beyond classical viewpoints such as operational, functional, and architectural views and views used for safety and security analysis. The model does so by incorporating elements of such systems for mutual introspections in situational awareness, capabilities, and intentions to enable a synergetic, trusted relation in the interaction of humans and CPSs, which we see as a prerequisite for their societal acceptance. The reference architecture is represented as a metamodel incorporating conceptual and behavioral semantic aspects. We illustrate the key concepts of the metamodel with examples from cooperative autonomous driving, the operating room of the future, cockpit-tower interaction, and crisis management.

 

The design and analysis of multi-agent human cyber-physical systems in safety-critical or industry-critical domains calls for an adequate semantic foundation capable of exhaustively and rigorously describing all emergent effects in the joint dynamic behavior of the agents that are relevant to their safety and well-behavior. We present such a semantic foundation. This framework extends beyond previous approaches by extending the agent-local dynamic state beyond state components under direct control of the agent and belief about other agents (as previously suggested for understanding cooperative as well as rational behavior) to agent-local evidence and belief about the overall cooperative, competitive, or coopetitive game structure. We argue that this extension is necessary for rigorously analyzing systems of human cyber-physical systems because humans are known to employ cognitive replacement models of system dynamics that are both non-stationary and potentially incongruent. These replacement models induce visible and potentially harmful effects on their joint emergent behavior and the interaction with cyber-physical system components.

 

As automation increases qualitatively and quantitatively in safety-critical human cyber-physical systems, it is becoming more and more challenging to increase the probability or ensure that human operators still perceive key artifacts and comprehend their roles in the system. In the companion paper, we proposed an abstract reference architecture capable of expressing all classes of system-level interactions in human cyber-physical systems. Here we demonstrate how this reference architecture supports the analysis of levels of communication between agents and helps to identify the potential for misunderstandings and misconceptions. We then develop a metamodel for safe human machine interaction. Therefore, we ask what type of information exchange must be supported on what level so that humans and systems can cooperate as a team, what is the criticality of exchanged information, what are timing requirements for such interactions, and how can we communicate highly critical information in a limited time frame in spite of the many sources of a distorted perception. We highlight shared stumbling blocks and illustrate shared design principles, which rest on established ontologies specific to particular application classes. In order to overcome the partial opacity of internal states of agents, we anticipate a key role of virtual twins of both human and technical cooperation partners for designing a suitable communication.

 

Research on ridesourcing has grown exponentially in recent years. This study details the results of a systematic review of 161 publications on ridesourcing that explore environmental sustainability and equity in North American cities. We identify five main areas of research. First, ridesourcing is associated with two modal shifts: a decline of the taxi industry and a more complicated association with public transit ridership. Second, several studies have documented workers' rights and the challenges of contingent labor. Third, demographic studies show associations between ridesouring and affluent riders, and spatial analyses indicate that ridesourcing may exacerbate existing patterns of inequity in cities. Fourth, ridesourcing has dubious claims to improve environmental sustainability: it has only a small effect on vehicle ownership, but it increases emissions associated with deadheading, and pooled services do not reduce vehicle miles traveled. Fifth, ridesourcing companies also tend to oppose regulatory responses and sharing data with potential regulators. The review concludes with suggestions on areas for future research. 

With the growth of commercial and recreational use of unmanned aerial vehicles (UAVs, or drones), there is increasing attention to the need for regulation. A systematic review is conducted using a multiple comparative perspective: across three political jurisdictions (the United States, the European Union, and Japan) and across two areas of societal implication and policy (i.e., privacy and safety), with additional comparisons drawn from regulations for related cyber-physical systems. The multiple comparative analysis conducted in this paper shows that safety is a much more salient concern than privacy. Moreover, safety is focused on technical features of the UAVs, registration and certification, and differentiation by use case. Privacy regulations tend to follow broader digital privacy guidelines. Although there are some privacy rules that are UAV-specific, many of them do not yet directly address privacy challenges that are specific for UAVs. Additional comparisons with safety and privacy policies for automated vehicles and the smart grid reveal areas of potential development for harmonization and policy guidance. The study concludes with ten recommendations for future policy development. 

A salient problem faced by governments and industry alike is how to accelerate energy transitions to enhance affordability, accessibility, and greenhouse-gas reduction. Bringing together acceleration processes and spatial scale dynamics, this study highlights the potential for electricity distribution to play a keystone role in the energy transition. We present and examine survey data of electricity distribution utilities in a region of the U.S. to show how trends in decentralization and digitization are intertwined with decarbonization. These trends rebalance economic value toward distribution networks and away from centralized infrastructure. The survey data show that electricity distribution organizations are deploying local, renewable generation projects that produce electricity for one-third (1/3) less than the cost from a centralized generation-and-transmission entity. We suggest that this change and others are likely to transform distribution operators into more broad-based local power organizations. Although the cost advantage of distributed generation seemingly marks a future of local control and decentralized organizational forms, spatial scale dynamics indicate countervailing centralization trends, including that distribution networks may evolve to dependency on external digital, engineering, and capital providers. The outcome of the resulting conflicts will affect the potential for transition acceleration to be enabled or reduced. 

When electrified transit systems make grid aware choices, improved social welfare is achieved by scheduling charging at low grid impact locations and times causing reduced loss, minimal power quality issues and reduced grid stress. Electrifying transit fleet has numerous challenges like non availability of buses during charging, varying charging costs, etc., that are related the electric grid behavior. However, transit systems do not have access to the information about the co-evolution of the grid’s power flow and therefore cannot account for the power grid’s needs in its day to day operation. In this paper we propose a framework of transportation-grid co-simulation analyzing the spatio-temporal interaction between the transit operations with electric buses and the power distribution grid. Real-world data for a day’s traffic from Chattanooga city’s transit system is simulated in SUMO and integrated with a realistic distribution grid simulation (using GridLAB-D) to understand the grid impact due to the transit electrification. Charging information is obtained from the transportation simulation to feed into grid simulation to assess the impact of charging. We also discuss the impact to the grid with higher degree of Transit electrification that further necessitates such an integrated Transportation-Grid co-simulation to operate the integrated system optimally. Our future work includes extending the platform for optimizing the charging and trip assignment operations.