著者
阿江 通良 湯 海鵬 横井 孝志
出版者
バイオメカニズム学会
雑誌
バイオメカニズム (ISSN:13487116)
巻号頁・発行日
vol.11, pp.23-33, 1992-05-20 (Released:2016-12-05)
被引用文献数
131 195

Inertia properties of the body segments such as segment mass, location of the center of mass, and moment of inertia can be measured and predicted in a number of ingenious approaches. They can be classified into a) direct measurements on cadavers, b) indirect measurements on living subjects, and c) mathematical modelling. However, there is little information upon which complete inertial estimates for Japanese people, especially male and female athletes, can be based. The purposes of this study were to determine the mass, center of mass location, and moments of inertia of the body segments for Japanese male and female athletes using a mathematical modelling approach, and to develop a set of regression equations to estimate inertia properties of body segments using simple anthropometric measurements as predictors. Subjects were 215 male and 80 female athletes belonging to various college sport clubs. Each subject, wearing swimming suit and cap, was stereo-photographed in a standing position. Ten body segments including the upper and lower torso were modelled to be a system of elliptical zones 2cm thick based on Jensen and Yokoi et al. Significant prediction equations based on body height, body weight, and segment lengths were then sought, and some prediction strategies were examined. The results obtained were summarized as follows: 1) Table 2 provides a summary of mass ratios, center of mass location ratios and radius of gyration ratios for males and females. There were many significant differences in body segment parameters between the two sexes. This suggests the need to develop different prediction equations for males and females. 2) Close relationships were noted between segment masses and segment lengths and body weight as predictors for all body segments. Table 5 provides coefficients of multiple regression equations to predict segment masses. 3) No close relationship was noted between independent variables and estimates of the center of mass location. This indicates that the variance in the center of mass location in proportion to the segment length was very small, and that location of centers of mass could be estimated by the mean ratio provided in Table 2. 4) Close relationships were noted between segment moments of inertia and segment lengths (except hand and foot), and body weight as predictors. Tables 6 and 7 provide coefficients of multiple regression equations to predict segment moments of inertia from segment lengths and body weight.
著者
横井 孝
出版者
駒澤大学
雑誌
駒澤國文 (ISSN:04523652)
巻号頁・発行日
vol.17, pp.137-142, 1980-03
著者
今西 裕一郎 伊藤 鉄也 野本 忠司 江戸 英雄 相田 満 海野 圭介 加藤 洋介 斎藤 達哉 田坂 憲二 田村 隆 中村 一夫 村上 征勝 横井 孝 上野 英子 吉野 諒三 後藤 康文 坂本 信道
出版者
国文学研究資料館
雑誌
基盤研究(A)
巻号頁・発行日
2010-04-01

本研究課題は、『源氏物語』における写本の単語表記という問題から、さらに大きな日本語日本文化の表記の問題を浮かび上がらせることとなった。当初の平仮名や漢字表記の違いというミクロの視点が、テキストにおける漢字表記の増加現象、またその逆の、漢字主体テキストの平仮名テキスト化という現象へと展開する過程で、テキストにおける漢字使用の変貌も「表記情報学」のテーマとなることが明らかになった。「文字の表記」は「文化の表記」「思想の表記」へとつながっている。「何が書かれているか」という始発点から「如何に書かれているか」に至る「表記情報学」は、今後も持続させるべき「如何に」の研究なのである。
著者
湯 海鵬 阿江 通良 横井 孝志 渋川 侃二
出版者
バイオメカニズム学会
雑誌
バイオメカニズム (ISSN:13487116)
巻号頁・発行日
vol.10, pp.107-118, 1990-09-10 (Released:2016-12-05)

Twisting from a somersault is one of the most used techniques in sports with airborne components such as diving, gymnastics, and so on. The purposes of this study were to investigate the effect of arm swing on the production of aerial twist during somersault and to identify factors affecting the production of the twist. By using a model composed of three rigid bodies, the mechanism of the production of twist from a somersault was confirmed theoretically. Then, quantitative calculation was done based on the model. In the calculation a performer was assumed to swing one arm downward from the symmetrical position with both arms above the head. To validate the model, twisting somersaults of two male skilled gymnasts were filmed and analyzed with 3-dimensional cinematography (DLT method) to compare with the model. The performances were forward twist-somersaults of 1/2, 1 and 3/2 revolutions from a vaulting horse. The factors affecting the generation of twist are discussed based on the results of computer simulation and film data. The results are summarized as follows: 1) An asymmetrical arm swing could generate a twist about the longitudinal axis of the body from a somersault. This arm swing tilted the principal axes of the body away from their original positions. The axis of the angular momentum that was initially established did not change in the airborne phase, but the momentum resolved into two perpendicular components, one about the body's principal longitudinal axis and the another about the body's frontal axis (principal axis). Thus, the somersaulting motion around the frontal axis will continue even though the frontal axis is now tilted from its original position, and in addition the body will begin to twist about its longitudinal axis. 2) The direction of the twist depended upon the initial directions of the somersault and/or arm swing. 3) Large angular velocity of the somersault before the change in the posture and large swing angle of the arm were effective for the generation of twisting. The smaller the moment of inertia about body's longitudinal axis, the larger the twisting that was produced.
著者
高木 昭浩 吉岡 克則 寺岡 悟見 相馬 努 矢野 今朝人 宮坂 正 横井 孝司 村瀬 研也
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.62, no.5, pp.729-733, 2006-05-20
被引用文献数
6 5

The following process conventionally has been followed to develop quantitative images of cerebral blood flow: (1) mean cerebral blood flow (mCBF) is calculated by the Patlak plot method; (2) a SPECT slice that includes the basal ganglia is selected; and (3) based on the value of mCBF calculated by the Patlak plot method, the SPECT slice is corrected by the Lassen method and developed into a SPECT image of quantitative regional cerebral blood flow. However, this process is complicated, and the values of rCBF have been reported to fluctuate because selection of the SPECT slice and the ROI setting are in the hands of the operator. We have developed new software that automates this analysis. This software enables automatic processing simply by inputting the value of mCBF in the normal hemisphere. Since there is no need for manual operations such as setting the ROI, reproducibility is improved as well. Regional cerebral blood flow as determined by this software is quite similar to that calculated by the conventional method, so the existing clinical evaluation does not need to be changed. This software is considered to be useful.
著者
阿江 通良 湯 海鵬 横井 孝志
出版者
バイオメカニズム学会
雑誌
バイオメカニズム
巻号頁・発行日
vol.11, pp.23-33, 1992
被引用文献数
67 195

Inertia properties of the body segments such as segment mass, location of the center of mass, and moment of inertia can be measured and predicted in a number of ingenious approaches. They can be classified into a) direct measurements on cadavers, b) indirect measurements on living subjects, and c) mathematical modelling. However, there is little information upon which complete inertial estimates for Japanese people, especially male and female athletes, can be based. The purposes of this study were to determine the mass, center of mass location, and moments of inertia of the body segments for Japanese male and female athletes using a mathematical modelling approach, and to develop a set of regression equations to estimate inertia properties of body segments using simple anthropometric measurements as predictors. Subjects were 215 male and 80 female athletes belonging to various college sport clubs. Each subject, wearing swimming suit and cap, was stereo-photographed in a standing position. Ten body segments including the upper and lower torso were modelled to be a system of elliptical zones 2cm thick based on Jensen and Yokoi et al. Significant prediction equations based on body height, body weight, and segment lengths were then sought, and some prediction strategies were examined. The results obtained were summarized as follows: 1) Table 2 provides a summary of mass ratios, center of mass location ratios and radius of gyration ratios for males and females. There were many significant differences in body segment parameters between the two sexes. This suggests the need to develop different prediction equations for males and females. 2) Close relationships were noted between segment masses and segment lengths and body weight as predictors for all body segments. Table 5 provides coefficients of multiple regression equations to predict segment masses. 3) No close relationship was noted between independent variables and estimates of the center of mass location. This indicates that the variance in the center of mass location in proportion to the segment length was very small, and that location of centers of mass could be estimated by the mean ratio provided in Table 2. 4) Close relationships were noted between segment moments of inertia and segment lengths (except hand and foot), and body weight as predictors. Tables 6 and 7 provide coefficients of multiple regression equations to predict segment moments of inertia from segment lengths and body weight.
著者
横井 孝 小田 寛貴 野村 精一 中村 俊夫 上野 英子 丹生 越子
出版者
名古屋大学
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.12, pp.80-88, 2001-03

第13回名古屋大学タンデトロン加速器質量分析計シンポジウム(平成12 (2000)年度)報告 名古屋大学タンデトロン加速器質量分析計第2号機の研究成果と利用計画