著者

江原 謙介 藤本 淳也 福田 一儀 松永 敬子 鳥山 稔 河野 真輝

出版者

日本スポーツ産業学会

雑誌

スポーツ産業学研究 (ISSN:13430688)

巻号頁・発行日

vol.31, no.2, pp.2_183-2_196, 2021-04-01 (Released:2021-04-26)

参考文献数

26

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This research compared university student-athletes and other university students to analyze differences in attitudes towards COVID-19. The objective was to examine the impact of student-athletes′ attitudes on their future athletic activities and perform verification that will contribute to the deliberation and creation of university support measures for student-athletes. Google Forms were used to administer an online questionnaire to university students nationwide. The responses to questions on the questionnaire were recorded on either 5 or 8 point scales, as well as open-ended questions without word limitations at the end of the questionnaire. The results were analyzed by separating results into two cohorts; student-athletes and other university students, and then categorizing responses to each question as positive or negative. Cross-tabulation was used and then Fischer′s exact test was performed. To analyze the open-ended questions, KH-Coder3 software, which excels at Japanese analysis and is used in a great deal of research, was used. The analysis found a significant difference for some questions. In particular, a greater percentage of student-athletes than other university students felt unease regarding infection at university facilities, the impact of infection on university life, and the impact on activities from April 2020 onwards. Some of the reasons for the higher percentage of responses indicating unease were the lack of transparency in student life, with universities not defining clear approaches.

著者

林 裕介 渡辺 昌宏 原 謙介

出版者

一般社団法人 日本機械学会

雑誌

Dynamics & Design Conference 2010 (ISSN:24242993)

巻号頁・発行日

pp._260-1_-_260-6_, 2010-09-14 (Released:2017-06-19)

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This paper deals with theoretical stability analysis of an active feedback control of web flutter which occurs to the web with both ends fixed and tensioned. In this paper, a non-contact active feedback control method of web flutter by using movable plates set at inlet or outlet of the passage are developed and its analytical model is constructed. The equations of motion of the flexible sheet coupled with the fluid flow controlled by the movable plates are obtained. The characteristic equation of the system is derived as a function of the flow velocity in the narrow gap. As a result, it is shown that the web flutter occurs to the web with increasing the flow velocity, and is effectively suppressed by the proposed non-contact flow control devices and active feedback control method. Furthermore, calculation results are verified by the experiments.

著者

CHALERMPONG Kolawach 山浦 弘 原 謙介

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.84, no.861, pp.17-00512-17-00512, 2018 (Released:2018-05-25)

参考文献数

15

被引用文献数

1

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This research studied an influence of the inertia of the hoisting rope on the dynamics of a mobile crane system. Two dynamics models of the mobile crane were formulated with the inertia included rope model and the massless rope model, and their dynamics response were compared. The floating frame of reference formulation was used in formulating the model of the deformable components. In the simulations, we variated the length of the rope and the mass of the hoisted load then applied the slewing motion to the boom for 10 seconds and let the system underwent free vibration for another 10 seconds while the boom angle was fixed. The deformation of the rope and the comparison of the hoisted load motion between two models were considered. The results illustrated that the rope model with included inertia was able to illustrated its bending during the crane operation and this deformation increased with the length of rope. It appeared that the deformation of the boom tip had influences on the deformation of the rope. In the motion of the hoisted load, the time - history data illustrated that the inertia included rope model had slightly higher frequency than the massless rope model during the free motion, and the trajectory also showed the slightly larger sway. In addition, the total calculation time of the inertia included rope model was around 13 times longer. The difference in the motion of the hoisted load from both models increased with the length of rope but decreased when the mass of load increased. In conclusion, the model with included inertia of rope showed different response to the massless rope model at long rope and light load condition, and this difference was decreased at short rope and heavy load condition.

著者

坂本 理絵子 山本 一雄 関原 謙介 篠原 文章 赤坂 晃彦 上森 真理子 川俣 博志 隈崎 達夫

出版者

公益社団法人日本放射線技術学会

雑誌

日本放射線技術學會雜誌 (ISSN:03694305)

巻号頁・発行日

vol.51, no.8, 1995-08-01

被引用文献数

1