著者
三宅 恵介 松井 崇 佐藤 武尊 横山 喬之 竹澤 稔裕 川端 健司 秋本 啓之
出版者
日本武道学会
雑誌
武道学研究 (ISSN:02879700)
巻号頁・発行日
vol.47, no.1, pp.19-27, 2014

The All-Japan Judo Championships (AJJC) is an open-weight tournament for determining the best judoka in Japan. The AJJC has been held under the Kodokan Judo Refereeing Rules (KDK Rules) since 1951. In 2011, the All-Japan Judo Federation (AJJF) introduced the International Judo Federation Refereeing Rules (IJF Rules), which were formulated to facilitate more dynamic judo (increased wins by <i>ippon</i>, decreased wins by judges' decisions, and decreased <i>mate</i>-time). Although the IJF Rules has facilitated dynamic judo in international competitions, their effects on the competition contents in the AJJC are still unknown. Here, we aimed to clarify whether the introduction of the IJF Rules facilitated dynamic judo in the AJJC.<BR>The 221 judo matches in the AJJC from 2008 to 2013 were separated into two groups, the tournaments following the KDK Rules (2008-2010) and those following the IJF Rules (2011-2013). Their data were extracted from the AJJC records by<i> Judo</i>, the official Kodokan journal, and from the match videos recorded by the AJJF. We analyzed the proportions of winning contents (wins by <i>ippon</i> or superior performance), winning methods (points from techniques or penalties, or judges' decisions), techniques for getting points (<i>te-waza, koshi-waza, ashi-waza, sutemi-waza, </i>or<i> katame-waza</i>) and the <i>mate</i>-time for each match. A chi-square test and an independent <i>t</i>-test were used to perform statistical analyses, and for each test, statistical significance was assumed at <i>P</i> value < 0.05.<BR>For the winning methods of the IJF Rules' and the KDK Rules' tournaments, the proportion of points from techniques (60.4% vs. 53.6%) and points from penalties (23.4% vs. 15.5%) showed no differences, but the proportion of wins by judges' decisions in the IJF Rules' tournaments was significantly lower than in the KDK Rules' tournaments (16.2% vs. 30.9%) (P < 0.05). Furthermore, the <i>mate</i>-time in the IJF Rules' tournaments was significantly shorter than in the KDK Rules' tournaments (77 s vs. 105 s) (P < 0.01). However, the winning contents and techniques for obtaining points showed no differences between the IJF Rules' and the KDK Rules' tournaments.<BR>We confirmed for the first time that the IJF Rules did not affect the winning contents and techniques for getting points, but decreased the proportion of judges' decisions and <i>mate</i>-time in the AJJC. These findings suggest that the IJF Rules partially facilitated dynamic judo in the AJJC.
著者
仲田 直樹 三嶋 康嗣 横山 喬之
出版者
一般社団法人 日本体育・スポーツ・健康学会
雑誌
体育学研究 (ISSN:04846710)
巻号頁・発行日
vol.65, pp.915-928, 2020 (Released:2020-12-12)
参考文献数
36

Judo, which has become popular in more than 200 countries and regions, has developed while merging with both national and ethnic sports. Among them, chidaoba practiced in Georgia is a remarkable example of anethnic martial art. However, no literature in Japan has yet described the technical form and historical background of chidaoba in detail. Therefore, the purpose of the present study was to clarify the essence of chidaoba by considering its historical and cultural background. The author has mastered basic Russian language skills and performed a search for academic essays and websites using keywords such as chidaoba or Georgia and ethnic martial arts in Russian. To ensure accurate translation from Russian into Japanese, the text was checked by several Japanese with native-level Russian language skills. Chidaoba matches were held on Christian holidays such as Saint George’s Day and the Svetitskhoveli Cathedral Holiday. Thus, chidaoba took root in cities and rural areas as an irreplaceable festival event. Later, when the Christian church banned some forms of ethnic entertainment and physical exercise, only chidaoba was exempt. Before a match, competitors were obliged to perform the traditional dance, kartuli or palavnuri. In chidaoba, any type of grasping from the waist and upper body is allowed, while grasping below the waist is prohibited. There are a wide variety of techniques in chidaoba, such as throwing from close contact, foot throwing, foot sweeps, reaps, and hooks. Due to the diversity of Georgians, ethnic groups vary from region to region. Moreover, there are several different forms of martial arts in the mountainous areas of Georgia, which are very different from chidaoba. In 2018, chidaoba was registered as an Intangible Cultural Asset. The results of this research should serve as a basic material for clarifying the outline of the Georgian ethnic martia art chidaoba.
著者
仲田 直樹 三嶋 康嗣 横山 喬之
出版者
一般社団法人 日本体育学会
雑誌
体育学研究 (ISSN:04846710)
巻号頁・発行日
vol.65, pp.915-928, 2020

Judo, which has become popular in more than 200 countries and regions, has developed while merging with both national and ethnic sports. Among them, chidaoba practiced in Georgia is a remarkable example of anethnic martial art. However, no literature in Japan has yet described the technical form and historical background of chidaoba in detail. Therefore, the purpose of the present study was to clarify the essence of chidaoba by considering its historical and cultural background. The author has mastered basic Russian language skills and performed a search for academic essays and websites using keywords such as chidaoba or Georgia and ethnic martial arts in Russian. To ensure accurate translation from Russian into Japanese, the text was checked by several Japanese with native-level Russian language skills. Chidaoba matches were held on Christian holidays such as Saint George's Day and the Svetitskhoveli Cathedral Holiday. Thus, chidaoba took root in cities and rural areas as an irreplaceable festival event. Later, when the Christian church banned some forms of ethnic entertainment and physical exercise, only chidaoba was exempt. Before a match, competitors were obliged to perform the traditional dance, kartuli or palavnuri. In chidaoba, any type of grasping from the waist and upper body is allowed, while grasping below the waist is prohibited. There are a wide variety of techniques in chidaoba, such as throwing from close contact, foot throwing, foot sweeps, reaps, and hooks. Due to the diversity of Georgians, ethnic groups vary from region to region. Moreover, there are several different forms of martial arts in the mountainous areas of Georgia, which are very different from chidaoba. In 2018, chidaoba was registered as an Intangible Cultural Asset. The results of this research should serve as a basic material for clarifying the outline of the Georgian ethnic martia art chidaoba.
著者
泉 聡志 横山 喬 寺岡 卓也 岩崎 篤 酒井 信介 斎藤 金次郎 名川 政人 野田 秀樹
出版者
一般社団法人日本機械学会
雑誌
日本機械学會論文集. A編 (ISSN:03875008)
巻号頁・発行日
vol.71, no.703, pp.380-386, 2005-03-25
被引用文献数
8 16

We have developed a new nut named 'super slit nut (SSN)', which realizes anti-loosening performance without complicated tightening procedures. In this study, tightening behavior and loosening behavior caused by shear load are analyzed by mean of three-dimensional finite element method. It is found that SSN has a prevailing torque of 15 to 19Nm, which closely agrees with experimental data. The load distribution of thread depends on the rotation angle of nut. At the angle of 24.6 degree, the distribution of 1st pitch turns to be 10% larger than that of conventional nut, reflecting the decrease in the thread at slit region. It is also found that the anti-loosening performance cas be realized by the thread contact force at the slit region. Since its contact force does not depend on the tightening force, the effect of anti-loosening performance drastically increases as the tightening force is decreased. Shear fracture would initiate not at slit region but at the bottom of 1st thread, whose stress is about 10% larger, as compared with conventional nut. Moreover, by mean of tensile and fatigue experiments, it is concluded that SSN involves sufficient strength in practical use.