Aichi University of Education (愛知教育大学, Aichi kyōiku daigaku) is a national university at Kariya, Aichi, Japan.The history of the university dates back to 1873 when it was called Aichi Prefectural Training Institution. In 1949, the university had become known as the Aichi University of Arts and Science and by 1966 it got a title of what it is called today, Aichi University of Education. In 2004, the title got changed again, this time to the National University Corporation Aichi University of Education.The school offers four education programs for undergraduate studies, as well as post graduate programs in the Graduate School of Educaction and Graduate School of Practitioners of Education.In 2016, the university signed an exchange agreement with the Jogjakarta State University.
This paper investigates the existence of m-stiff configurations in the unit sphere Sd-1, which are spherical (2m - 1)-designs that lie on m parallel hyperplanes. We establish two non-existence results: (1) for each fixed integer m > 5, there exists no m-stiff configuration in Sd-1 for sufficiently large d; (2) for each fixed integer d > 10, there exists no m-stiff configuration in Sd-1 for sufficiently large m. Furthermore, we provide a complete classification of the dimensions where m-stiff configurations exist for m = 2,3,4,5. We also determine the non-existence (and the existence) of m-stiff configurations in Sd-1 for small d(3 <= d <= 120) with arbitrary m, and also for small m(6 <= m <= 10) with arbitrary d. Finally, we conjecture that there is no m-stiff configuration in Sd-1 for (d, m) with d >= 3 and m >= 6. (c) 2025 Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
We define a two-particle quantum walk of identical particles on a graph G via the one-particle Grover walk on the Kronecker product G ⊗ G, and call it the two-particle Grover walk. In systems of identical particles, quantum mechanics requires that quantum states have a certain invariance with respect to the exchange of particles. Focusing on the symmetry of the Kronecker product G ⊗ G as a graph, we show that the time evolution operator of this walk commutes with the swap operator, which ensures that this requirement is satisfied. Furthermore, we study the entanglement entropy of quantum states evolved by this walk. For the complete bipartite graph K_n,n, we completely determine the values of n for which the quantum states evolved from specific initial states attain the upper bound of the entropy at some time, and prove that they are exactly 1 and 2.
Abstract This study visualizes long-term shifts in interregional trade between Ishikawa Prefecture in the Hokuriku region and Aichi Prefecture in the Tokai region, focusing on their trade relationships with other prefectures in the Chubu region. Using the hypothetical regional extraction method and multiregional input–output tables for five time points (1995, 2000, 2005, 2011, and 2015), the economic effects of hypothetically removing these prefectures from the regional production network were analyzed. The analysis revealed that interregional trade within the Chubu region expanded in both prefectures after 2011 despite a substantial decline in production owing to the Great East Japan Earthquake. By 2015, production levels had recovered to approximately the same level as in 2005, and the trend of increasing interregional trade continued. Thus, the expansion in interregional trade observed after 2011 was not temporary; both Ishikawa and Aichi prefectures have since strengthened their trade relationships with other prefectures in the Chubu region. Positioning the Great East Japan Earthquake within the international literature on disaster propagation through production networks, this paper provides a comparable, multi-period indicator of interregional embeddedness and its persistence after large shocks. It also highlights the importance of resilient interregional trade networks in mitigating future disruptions, offering policy-relevant insights.
This paper is a continuation of a recent work [5] on the imaginary quadratic fields ℚ(√(-D_s)) where 5D_s = F_10 s+5 , with F_n the n -th Fibonacci number. In a previous paper [5], it was shown that the class number of ℚ(√(-D_s)) is divisible by 5 for all nonnegative s except possibly those s ≡ 0 20 . In this paper, we refine the argument and remove that restriction, proving that the class number of ℚ(√(-D_s)) is divisible by 5 for every positive integer s . Our proof combines a construction of a quintic polynomial, properties of Fibonacci-Lucas numbers, and Sase’s ramification criterion to exhibit an unramified C_5 -extension within a dihedral extension of degree 10.
Abstract This study evaluates Northern winter seasonal forecasts initialized in early November to assess both whether they can skillfully predict the occurrence or absence of one or more major sudden stratospheric warmings (MSSWs) in the subsequent December‐January‐February period and whether ensemble members provide internally consistent predictions of MSSW occurrence. These questions are important because MSSWs are known to influence anomalous tropospheric and surface weather conditions; however, the predictability of MSSWs at the seasonal time scale remains unclear. Results based on the coefficient—a special case of the correlation coefficient for binary data—from 43‐season forecast data of one primary system demonstrate that the members are internally consistent with each other but that they are not significantly consistent with observations, suggesting a lack of or only weak forecast skill. The lack of skill is supported by results using other metrics. These conclusions are broadly robust across the different MSSW definitions tested. Similar results are found in an additional analysis using shorter 24‐season forecasts from each of the six systems. Internal consistency is not found in one system with the smallest ensemble size, while some hint of skill is observed in limited cases depending on the system and target latitude for MSSWs. It is worth noting that the results, including those related to the coefficient, vary depending on both ensemble size and the number of seasons.
