Removing riverine floating debris is an essential environmental conservation practice to mitigate flood risks and reduce water pollution.This floating debris often accumulates around the upstream side of river weirs. While much of this riverine accumulated debris has traditionally been managed through regular manual patrols and removal, an automated detection system would significantly reduce the burden of these manual tasks. This paper reports on a deep learning-based method for the automated detection of accumulated floating debris around a river weir in Asuwa River. We constructed a deep learning model using a Convolutional Neural Network (CNN) trained on images captured by fixed cameras monitoring the river weir. Through repeated training of CNN and detection experiments, the CNN model achieved an accuracy of 0.86, a precision of 0.84, a recall of 0.90, and an F-measure of 0.87. This demonstrates the model's high effectiveness in identifying debris accumulation. The proposed system, utilizing fixed-camera monitoring, enables real-time detection, which can significantly reduce the need for manual patrols and contribute to more efficient river management.

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This study evaluated a TOC-based soil water-shaking extraction method using oven-dried subsamples to estimate available nitrogen in air-dried paddy soils in Fukui Prefecture. In this method, air-dried soils are oven-dried before extraction, and total organic carbon (TOC) extracted by shaking the oven-dried soils in water is measured with a TOC analyzer as an indicator of available nitrogen. The TOC-based method was compared with a flooded incubation–Bremner distillation procedure regarded as a conventional reference method for available nitrogen; with a 0−10 mg C/L calibration range and 20-fold dilution of extracts, the estimated available nitrogen values showed good agreement with those obtained by this reference method. These results show that the TOC-based method is a practical tool for evaluating available nitrogen in paddy soils and is applicable in small-scale testing laboratories lacking nitrogen-specific analytical instruments.

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We theoretically investigate the Josephson effect in a Josephson junction consisting of a ferromagnetic layer sandwiched between two superconductors. Using the quasiclassical Green’s function method and perturbative calculations, we derive analytical expressions for the first harmonic Josephson current (FHJC) and the second harmonic Josephson current (SHJC) in the diffusive regime. Both components exhibit damped oscillatory behavior as functions of the ferromagnetic layer thickness, accompanied by sign changes, indicating the occurrence of 0-π transitions. The analytical results clarify that the oscillation period of the SHJC is half that of the FHJC, while its damping rate is twice as large. These findings suggest that a thin ferromagnetic layer is essential to realize a significantly large SHJC.

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Socrates practiced philosophy through dialogue and discussion. His method of questioning, called the elenchus, takes the form of reductio ad absurdum. Due to its logical structure, debate has persisted over whether it is an appropriate method for pursuing truth. This paper examines Davidson's treatment of the elenchus and considers the significance of dialogue from another perspective. According to Davidson, it is precisely because dialogue is the primary arena where concepts are formed that there is significance in conducting philosophy through dialogue. The purpose of this paper is to further advance his examination, centered on the idea of “conceptual clarification” (or “conceptual transformation”).

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This paper examines memories of war and historical materials related to war. In Japan, the number of people who experienced World War II is decreasing day by day. Therefore, it becomes important to preserve and pass down the war experiences and the 'memories' of war as historical materials. Amid this situation, on June 14, 2025, an interview was conducted with Toshio Yamamoto, a resident of Sabae City, whose father had served on the Chinese front. This paper transcribes interviews and considers the documentation and transmission of war 'memories'.

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This paper reports on an English presentation project conducted at the National Institute of Technology, Fukui College. The project emphasizes the pedagogical application of AI tools in classroom practice. Since 2016, the author has incorporated English presentations into the curriculum, initially in conjunction with student study excursions. The activity was temporarily halted from 2020 to 2022 due to the pandemic and the author's absence for health reasons, but it resumed in 2023 with notable updates. The 2024 and 2025 iterations of the project intentionally integrated AI technologies, such as DeepL Translator, DeepL Write, and the text-to-speech program “On-doku san.”These digital resources assisted students in drafting, refining, and rehearsing their English scripts. Microsoft Teams served as the primary communication platform, offering learners access to comprehensive instructional materials, timelines, and exemplar resources. This paper describes the stages involved in scriptwriting and pronunciation practice, emphasizing students’ autonomous engagement with AI support.The paper also introduces examples of student presentations and shares findings from a survey evaluating the perceived usefulness of AI in improving students' performance and self-confidence. The paper concludes by offering pedagogical insights and practical recommendations for optimizing AI-supported language instruction.

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This paper reconstructs a four-decade research trajectory on the Negative Raising (NR) phenomenon, integrating shifts in theoretical perspectives and methodological approaches. NR refers to sentences like "I don’t think he is right," which semantically equate to "I think he is not right." The phenomenon’s semantic ambiguity and syntactic-pragmatic complexity have motivated diverse linguistic inquiries. The author’s early work (1980s–1990s) focused on syntactic transformations and pragmatic functions, introducing the concept of NEG-Returning to capture speaker attitudes. Cross-linguistic studies with Japanese revealed differences in NR realization and pragmatic motivations. From the 2000s, a cognitive linguistic framework was developed, drawing on Langacker’s theories to reinterpret NR as a cognitive shift in speaker inclination rather than syntactic movement. The 2009 doctoral dissertation integrated corpus analysis and cross-linguistic comparison, elucidating NR’s form-function-phonology correlations and universal versus language-specific aspects. This paper organizes the research into three phases: predissertation, dissertation, and post-dissertation studies, highlighting theoretical refinements and applications to syntax, discourse, and phonetics. The concluding discussion synthesizes the overall findings and outlines future research directions, advocating a cognitive-pragmatic approach to understanding NR beyond traditional syntactic accounts.

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This paper explores the educational significance of debate activities at technical colleges, focusing on the ongoing “Debate Contest” at the National Institute of Technology, Fukui College (Fukui Kosen), which has been held annually since 1997. In the context of Japanese colleges of technology, educational efforts have traditionally prioritized science and engineering, often at the expense of activities fostering critical thinking, communication, and collaborative skills. However, with growing attention to 21st-century competencies, debate has emerged as a promising practice to cultivate these essential abilities. The Debate Contest at Fukui Kosen is unique in that it involves not only students but also faculty members as active participants. This inclusive structure promotes the formation of a collaborative learning community,transcending the boundaries of a conventional school event. Moreover, students involved in the planning and management of the event—mainly cultural committee members—gain valuable experience in leadership, coordination, and problem-solving. By comparing Fukui Kosen’s practice with national-level competitions such as Debate KOSHIEN and debate programs at other Kosen institutions, this paper highlights the distinct characteristics and educational potential of the Fukui model. While it may lack the formal rigor of academic policy debate, it excels in accessibility, creativity, and engagement, making it well-suited to the educational environment of technical colleges. This study aims to clarify the challenges and future possibilities of institutionalizing debate culture within Kosen education. By documenting and analyzing the implementation process and educational outcomes of the Fukui Debate Contest, the paper offers insights for educators and institutions seeking to integrate dialogic learning into technical and vocational education contexts.

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This study examines the phenomenon of polarity-reversed ellipsis in Japanese, focusing on cases where the anaphoric expression soo (“so”) refers to a negated proposition implied by a preceding statement. While earlier research, notably Yagi, Sakamoto, and Tatsumi (2022),has analyzed polarity reversal primarily in connection with syntactic Neg-raising (NR) predicates such as omou (“think”), this paper demonstrates that polarity-reversed interpretations extend beyond NR predicates to include non-NR predicates such as kangaeru(“consider”)and handan-suru (“judge”). Drawing on two large-scale acceptability judgment surveys with a total of 466 participants (students and faculty),the analysis shows that polarity-reversed soo is systematically licensed in contexts where the negated predicate functions as a denial,activating a discourse representation of ¬P (not-P) shared among interlocutors. In addition, chi-square tests conducted on acceptability judgment data from the two surveys (N = 466) revealed statistically significant differences in several conditions, particularly with respect to response type in dialogic contexts, while also indicating that such effects are not uniform across all structures. These findings indicate that the licensing of polarity-reversed ellipsis relies not solely on syntactic identity constraints but also on pragmatic inference and discourse-level factors. By integrating empirical evidence and cognitive-pragmatic analysis, this study deepens our understanding of the interaction between negation, anaphora, and discourse structure in Japanese. It also highlights the need for models of ellipsis resolution that incorporate pragmatic and interactional considerations, offering insights for theoretical linguistics and Japanese language education.

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The lecture on radiation has been given in 2nd grade physics class in NIT Fukui college for a long time. In this report, we will discuss the changes in the lecture materials and questionnaire survey to measure the effectiveness of education in this decade. In recent surveys, text mining techniques were applied to analyze the free-form responses, and it was revealed that the attitude of students was significantly changed by the lecture. The results of the survey suggest that the radiation education had a positive effect on the students to change the awareness of radiation.

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