3,598 research outputs found

    An Empirical Framework for Intersection Optimization Based on Uniform Design

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    Operational performance optimization of signalized intersections is one of the most important tasks for traffic engineers and researchers. To compensate for the limitations of practical implementation, simulation software packages have been widely used to evaluate different optimization strategies and thus to improve the efficiency of the intersections as well as the entire network. However, for the existing optimization studies on signalized intersections, the relationships among various optimization measures and the combination of strategies have not been fully investigated. In this paper, uniform design experimentation was introduced to combine different optimization measures into strategies and achieve the minimum time cost in model construction. VISSIM software package was then calibrated and used to evaluate various optimization strategies and identify the one with the best measurement of performance, namely, control delay at the signalized intersection. By taking a representative congested intersection in Shanghai as a case study, the optimal strategy was identified to reduce the overall control delay by 27.3%, which further verified the modeling capability of the proposed method

    On the origin of critical temperature enhancement in atomically-thin superconductors

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    Recent experiments showed that thinning gallium, iron selenide and 2H tantalum disulfide to single/several monoatomic layer(s) enhances their superconducting critical temperatures. Here, we characterize these superconductors by extracting the absolute values of the London penetration depth, the superconducting energy gap, and the relative jump in specific heat at the transition temperature from their self-field critical currents. Our central finding is that the enhancement in transition temperature for these materials arises from the opening of an additional superconducting gap, while retaining a largely unchanged bulk superconducting gap. Literature data reveals that ultrathin niobium films similarly develop a second superconducting gap. Based on the available data, it seems that, for type-II superconductors, a new superconducting band appears when the film thickness becomes smaller than the out-of-plane coherence length. The same mechanism may also be the cause of enhanced interface superconductivity.Comment: 43 pages, 12 figure

    Mapping interdisciplinary collaboration in music education: analysis of models in higher education across North America, Europe, Oceania, and Asia

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    Interdisciplinary collaboration is an emerging imperative in music education, but current understanding of global practices remains limited. Prior studies have focused narrowly on specific programs within limited geographic areas. However, there is minimal quantitative mapping of initiatives across institutions and regions. Contextual insights explaining regional variations are also scarce. Hence, this study aims to address these gaps by conducting a comprehensive analysis of interdisciplinary programs, partnerships, events, and publications across leading global music institutions using a mixed methods approach. The analysis reveals significant diversity in models and determinants of productivity across regions. For instance, while Europe leads in formal integration and research output, North America prioritizes technology-enabled innovation through media and emerging tools. Partnerships are ubiquitous but focus areas and curricular integration vary. The findings reveal significant diversity in interdisciplinary education practices and formats worldwide, implying a need for contextualized implementation aligned to institutional strengths rather than a one-size-fits-all approach. Therefore, as music education evolves, tailored interdisciplinary strategies that blend local priorities with global best practices are recommended to creatively nurture multifaceted skills and maximize potential for innovation. Thus, this research contributes an invaluable knowledge base to inform evidence-based, nimble policies and frameworks for cultivating cutting-edge, socially engaged musicians and ventures worldwide

    Teaching Autonomous Vehicles to Express Interaction Intent during Unprotected Left Turns: A Human-Driving-Prior-Based Trajectory Planning Approach

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    Incorporating Autonomous Vehicles (AVs) into existing transportation systems necessitates examining their coexistence with Human-driven Vehicles (HVs) in mixed traffic environments. Central to this coexistence is the AVs' ability to emulate human-like interaction intentions within traffic scenarios. We introduce a novel framework for planning unprotected left-turn trajectories for AVs, designed to mirror human driving behaviors and effectively communicate social intentions. This framework consists of three phases: trajectory generation, evaluation, and selection.In the trajectory generation phase, we utilize real human-driving trajectory data to establish constraints for a predicted trajectory space, creating candidate motion trajectories that reflect intent. The evaluation phase incorporates maximum entropy inverse reinforcement learning (ME-IRL) to gauge human trajectory preferences, considering aspects like traffic efficiency, driving comfort, and interactive safety. During the selection phase, a Boltzmann distribution-based approach is employed to assign rewards and probabilities to the candidate trajectories, promoting human-like decision-making. We validate our framework using an authentic trajectory dataset and conduct a comparative analysis with various baseline methods. Our results, derived from simulator tests and human-in-the-loop driving experiments, affirm our framework's superiority in mimicking human-like driving, expressing intent, and computational efficiency. For additional information of this research, please visit https://shorturl.at/jqu35

    Thickness dependence of superconductivity and superconductor-insulator transition in ultrathin FeSe films on SrTiO3(001) substrate

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    Interface-enhanced high-temperature superconductivity in one unit-cell (UC) FeSe film on SrTiO3(001) (STO) substrate has recently attracted much attention in condensed matter physics and material science. Here, by ex situ transport measurements, we report on the superconductivity in FeSe ultra-thin films with different thickness on STO substrate. We find that the onset superconducting transition temperature (Tc) decreases with increasing film thickness of FeSe, which is opposite to the behavior usually observed in traditional superconductor films. By systematic post-annealing of 5 UC FeSe films, we observe an insulator to superconductor transition, which is accompanied with a sign change of the dominated charge carriers from holes to electrons at low temperatures according to the corresponding Hall measurement
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