Yokohama National University

YNU-Repository (Yokohama National University)
Not a member yet
    14532 research outputs found

    A Study on the History and Current Situation of Performance Evaluation in China

    Full text link

    Brillouin frequency shift dependences on strain and temperature in perfluorinated polymer optical fibers with unique core dopants

    No full text
    Optical fiber sensors based on Brillouin scattering have attracted extensive attention due to their ability to perform distributed strain and temperature measurements. In this study, we explore the Brillouin frequency shift (BFS) characteristics in perfluorinated graded-index polymer optical fibers (POFs) doped with unique materials, focusing on the BFS dependencies on strain and temperature. Our results reveal a strain sensitivity coefficient of –195 MHz/%, which is approximately 1.6 times higher in absolute value than previously reported for other POFs, while the temperature sensitivity (–3.1 MHz/K) remains comparable to previous findings

    Reactive persistent surveillance by heterogeneous multi-agents with energy constraint

    No full text
    When natural disasters occur, accurately assessing the situation in a changing environment requires rapid and persistent observation. This paper focuses on the problem of conducting persistent observations using heterogeneous multi-agents with different observation capabilities and maximum operational time. To enable long-term operations covering vast environments, agents must replenish energy resources such as batteries and fuel. In this research, we discuss a method for selecting the direction of movement for observation by calculating utility values based on mutual information and remaining energy. Additionally, since mutual information reflects the different observation capabilities of each agent type, agents can move to locations where they can obtain the most information through their own observations. Through utility value-based action determination, agents fundamentally decide their movement directions based on mutual information, but as their energy levels decrease, they become more likely to choose the shortest path to a supply station. To validate the proposed method, we conducted numerical experiments involving persistent observation simulations in two changing environments: a simplified artificial environment and an environment representing a large-scale disaster in progress. The experimental results confirm that our proposed method successfully enables heterogeneous multi-agents to perform reactive observations while resupplying energy

    Cavity-mediated coupling between local and nonlocal modes in Landau polaritons

    Full text link
    The multimode ultrastrong coupling (USC) regime has emerged as a novel platform for accessing previously inaccessible phenomena in cavity quantum electrodynamics. Of particular interest are cavity-mediated correlations between local and nonlocal excitations, or equivalently, between modes at zero and finite in-plane momentum, which offer new opportunities for controlling light–matter interactions across space. However, direct experimental evidence of such interactions has remained elusive. Here,we demonstrate nonlocal multimode coupling in a Landau polariton system, where cavity photons simultaneously interactwith the zero-momentum cyclotron resonance and finite-momentum magnetoplasmons of GaAs two-dimensional electron gas. Our slot cavities, with their subwavelength mode volumes, supply in-plane momentum components that enable the excitation of finite-momentum matter modes. Terahertz time-domain magnetospectroscopymeasurements reveal a clear splitting of the upper-polariton branch, arising from hybridization between magnetoplasmon modes and the cavity–cyclotron-resonance hybrids. Extracted coupling strengths confirm USC of the cyclotron resonance and strong coupling of the magnetoplasmon modes to the cavity field, respectively. The experimental results are well captured by the multimode Hopfield model and finite-element simulations. These findings establish a pathway for engineeringmultimode light–matter interactions involving zero- and finite-momentum matter modes in the USC regime

    Appendix

    Full text link
    付録資料(教材・テスト等)Appendix 1: Chants Appendix 2: Storytelling Task Appendix 3: Sample Written Tests Appendix 4: Questionnair

    14,232

    full texts

    14,532

    metadata records
    Updated in last 30 days.
    YNU-Repository (Yokohama National University)
    Access Repository Dashboard
    Do you manage Open Research Online? Become a CORE Member to access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard! 👇