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Abstract This paper presents novel multicore fibers with broadband emission in the 1.4–2.1 μm range. Based on our previous work with barium gallo-germanate glasses and fibers, the 4 and 11-core fiber structures, each containing core glasses doped with Er3+ and Yb3+/Tm3+/Ho3+, were developed. Our efforts have resulted in flat emission in 3 dB and 10 dB bands, achievable under excitation at 796 nm, 808 nm, 940 nm, and 980 nm. The measured emission spectra of these fibers are described as a superposition of emission bands from each individual core, corresponding to the transitions of Er3+, Tm3+, and Ho3+ ions. Our method demonstrates the potential of emission profiling in multicore optical fibers as a new way to construct eye-safe broadband fiber sources.

Students often experience social and psychological barriers to success in General Chemistry, which is a key gateway to many students' science pathways. Learning assistants (LAs) have the potential to reduce these barriers and to strengthen students' sense of belonging in General Chemistry and STEM more broadly. Here, we used a 17-item Likert scale to determine whether incorporating LAs into General Chemistry I and II enhances students' sense of belonging in these courses. The incorporation of LAs into General Chemistry I had a significant positive effect and a medium to large effect size for students in all student groups examined: women and men; students in both racially and ethnically underrepresented and well-represented groups; first- and continuing-generation students. In General Chemistry II, similar results were observed for women and men; students in well-represented racial and ethnic groups; continuing-generation students. Further, we asked students to reflect on the impact that working with LAs had on their sense of belonging in STEM and confidence in talking about science. Sixty percent of students indicated that working with LAs had a positive impact on their STEM belonging, with five themes describing LA impacts: reducing isolation, serving as inspirational role models, providing mentoring, increasing opportunities for engagement and confidence building, and serving as accessible and approachable sources of support. Sixty-one percent of students also indicated that working with LAs increased their confidence in talking about science, with three themes emerging: fostering an environment with a lower risk of negative judgment, providing increased opportunities for feedback, and supporting students as they practiced their growing skills. Together, these results indicate that LAs can be an important means to reduce social and psychological barriers for students in gateway science courses, increasing their sense that they belong to the class and STEM more broadly.

Driving characteristics of bicyclists and motorists differ significantly in critical, uncritical and unaffected situations in road traffic. When bicyclists cross the path of right-turning motorists, bicyclists seem to mitigate conflicts that can develop into crashes, while motorists seem to avoid non-critical but close interactions that can develop into conflicts. This is one of the key findings of the evaluation of a recently developed and successfully tested cooperative driver assistance system (C-ADAS) that warns right-turning motorists of potential collisions. The warning is given by a special traffic light, which we called ‘amber light’, lighting up only in dangerous situations. Whether a situation becomes dangerous or not is determined by a decision tree, fed by the measured kinematics and specific surrogate measures of safety of the interacting road users. Most notably, the results demonstrate that criticality can be rated by measuring anticipation (or surprise) by computing the cross-power spectrum and applying entropy metric on the acceleration functions of the road users. However, one of the outcomes is that the time for the road users to perceive the amber light state might be too low to react properly. These findings can be used to improve the performance of such a C-ADAS.

Abstract Ride‐hailing services have the potential to play a major role within future transport systems. While the operation as well as environmental, social and economic consequences are research subjects, the focus in the literature lies on system efficiency and profitability. In this study, vehicle relocation strategies are investigated with respect to service provision equity using an agent‐based simulation approach. The aim is to identify ways of operation that support social fairness while maintaining the profitability and effectiveness of the service. The results show that a typical demand‐anticipatory relocation strategy leads to an imbalance in the spatial distribution of mean wait times for the use case of Berlin. This can be significantly improved by applying different relocation strategies. As a consequence, the overall demand for the system rises while the ratio of empty vehicle kilometres increases slightly.