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Takeshi Miyakawa 《Educational Studies in Mathematics》2017,94(1):37-54
This paper reports the results of an international comparative study on the nature of proof to be taught in geometry. Proofs in French and Japanese lower secondary schools were explored by analyzing curricular documents: mathematics textbooks and national curricula. Analyses on the three aspects of proof—statement, proof, and theory—suggested by the notion of Mathematical Theorem showed differences in these aspects and also differences in the three functions of proof—justification, systematization, and communication—that are seemingly commonly performed in these countries. The results of analyses imply two major elements that form the nature of proof: (a) the nature of the geometrical theory that is chosen to teach and (b) the principal function of proof related to that theory. This paper suggests alternative approaches to teach proof and proving and shows that these approaches are deeply related to the way geometry is taught. 相似文献
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A featured microchip owning three big reservoirs and long turned geometry channel was designed to improve the detection limit of DNA fragments by using floating electrokinetic supercharging (FEKS) method. The novel design matches the FEKS preconcentration needs of a large sample volume introduction with electrokinetic injection (EKI), as well as long duration of isotachophoresis (ITP) process to enrich low concentration sample. In the curved channel [∼45.6 mm long between port 1 (P1) and the intersection point of two channels], EKI and ITP were performed while the side port 3 (P3) was electrically floated. The turn-induced band broadening with or without ITP process was investigated by a computer simulation (using CFD-ACE+ software) when the analytes traveling through the U-shaped geometry. It was found that the channel curvature determined the extent of band broadening, however, which could be effectively eliminated by the way of ITP. After the ITP-stacked zones passed the intersection point from P1, they were rapidly destacked for separation and detection from ITP to zone electrophoresis by using leading ions from P3. The FEKS carried on the novel chip successfully contributed to higher sensitivities of DNA fragments in comparison with our previous results realized on either a single channel or a cross microchip. The analysis of low concentration 50 bp DNA step ladders (0.23 μg∕ml after 1500-fold diluted) was achieved with normal UV detection at 260 nm. The obtained limit of detections (LODs) were on average 100 times better than using conventional pinched injection, down to several ng∕ml for individual DNA fragment. 相似文献
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Combined effects of pre-cooling and water ingestion on thermoregulation and physical capacity during exercise in a hot environment 总被引：2，自引：1，他引：1
The aim of the present study was to determine the combined effects of pre-cooling and water ingestion on thermoregulatory responses and exercise capacity at 32 degrees C and 80% relative humidity. Nine untrained males exercised for 60 min on a cycle ergometer at 60% maximal oxygen uptake (VO2max) (first exercise bout) under four separate conditions: No Water intake, Pre-cooling, Water ingestion, and a combination of pre-cooling and water ingestion (Combined). To evaluate the efficacy of these conditions on exercise capacity, the participants exercised to exhaustion at 80% VO2max (second exercise bout) following the first exercise bout. Rectal and mean skin temperatures before the first exercise bout in the Pre-cooling and Combined conditions were significantly lower than in the No Water and Water conditions. At the end of the first exercise bout, rectal temperature was lower in the Combined condition (38.5 +/- 0.1 degrees C) than in the other conditions (No Water: 39.1 +/- 0.1 degrees C; Pre-cooling: 38.7 +/- 0.1 degrees C; Water: 38.8 +/- 0.1 degrees C) (P < 0.05). Heat storage was higher following pre-cooling than when there was no pre-cooling (P < 0.05). The final rectal temperature in the second exercise bout was similar between the four conditions (39.1 +/- 0.1 degrees C). However, exercise time to exhaustion was longer (P < 0.05) in the Combined condition than in the other conditions. Total sweat loss was less following pre-cooling than when there was no pre-cooling (P < 0.001). Evaporative sweat loss in the Water and Combined conditions was greater (P < 0.01) than in the No Water and Pre-cooling conditions. Our results suggest that the combination of pre-cooling and water ingestion increases exercise endurance in a hot environment through enhanced heat storage and decreased thermoregulatory and cardiovascular strain. 相似文献
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Naoyuki Ebine Hoby Hasina Rafamantanantsoa Youichirou Nayuki Kunio Yamanaka Kouzou Tashima Takeshi Ono 《Journal of sports sciences》2013,31(5):391-397
To determine the daily energy requirements of professional soccer players during a competitive season, we measured total energy expenditure in seven players (age 22.1 - 1.9 years, height 1.75 - 0.05 m, mass 69.8 - 4.7 kg; mean - s ) using the doubly labelled water method. Energy intake was simultaneously estimated from 7 day self-report dietary records. Mean total energy expenditure and energy intake were 14.8 - 1.7 MJ · day -1 (3532 - 408 kcal· day -1 ) and 13.0 - 2.4 MJ · day -1 (3113 - 581 kcal· day -1 ), respectively. Although there was a significant difference between total energy expenditure and energy intake ( P ? 0.01), there was a strong relationship between the two ( r = 0.893, P ? 0.01). Basal metabolic rate and recommended energy allowance calculated from the Recommended Dietary Allowances for the Japanese were 7.0 - 0.3 MJ ·day -1 (1683 - 81 kcal· day -1 ) and 15.6 - 0.8 MJ · day -1 (3739 - 180 kcal· day -1 ), respectively. A physical activity level (total energy expenditure/ basal metabolic rate) of 2.11 - 0.30 indicated that, during the competitive season, professional soccer players undertake much routine physical activity, similar to that of competitive athletes during moderate training. Energy intake estimated using dietary records was under-reported, suggesting that its calculation from these data does not predict energy expenditure in soccer players. 相似文献
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Yoko Yamasaki 《History of education》2013,42(5):575-588
Little is known about the impact of Western educational ideals in Japan during the Meiji (1868–1912), Taisho (1912–1926) and Showa (post‐1926) eras, although, in reality, there was considerable interest among Japanese educators in Western thought and practice and there were numerous attempts to disseminate these ideas widely. This article highlights some of the more significant of these developments and attempts to assess their impact and their interpretation in a Japanese context. Translations of foreign philosophical and educational works on the one hand and the publication of teachers' magazines on the other were the two viaducts for what became little short of a Japanese educational movement that was one of the stepping stones to the modernisation of Japan and which has resonated down to the present. In this article this process is described through its chronological phases, during the period which saw Japan's transition from an intellectually isolated, inward‐looking society into one which developed as a democracy and saw the coming of industrialisation before moving into a period of Fascist supernationalism. 相似文献
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Takeshi Yoneyama 《Sports Engineering》2018,21(4):277-282
The relation between the ski side-cut radius and deflection during a turn has been investigated. Using a model wherein the ski slides along a turn of a constant radius with an edging angle, it was found that the side-cut radius increases and the ski-deflection radius decreases as the edging angle increases. Even if additional deflection is necessary in the front part of the ski to form the turn groove, the side-cut radius is still the same in the groove. Owing to the constant side-cut radius of existing skis in the turn groove with a large edging angle, the top wide part of the ski causes an increase in skiing resistance. To reduce the skiing resistance, a prototype variable side-cut ski was fabricated, and test skiing was performed. Athletes felt more stable in the turn with the variable side-cut ski and found it easier to increase speed. 相似文献
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TANIYAMA Kenta MORII Takeshi KOIZUMI Shinya NOGUCHI Kazuhiro KOTANI Yukihiro KATTO Jiro 《浙江大学学报(A卷英文版)》2006,7(Z1)
We propose an on-demand multiparth routing algorithm in a mobile ad hoc network for video transmission and evaluate its real world performance in video streaming application. There have been a number of multipath routing protocols extended from AODV which is a well-known single path routing protocol. Multipath routing protocols indicate good performance in the reduction of route discovery latency and unnecessary routing packets in simulations. We show that the route establishment using source route lists provided by us (Hu and Johnson, 2002) can reduce the route discovery latency, select stable routes automatically, and work well for live video streaming without limitation of the hop count based approaches. We evaluate this proposed method compared with the original AODV by using eight laptop PCs and demonstrate live streaming experiments. 相似文献
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Yasushi Takata Anri Inaki Takafumi Mochizuki Hitoaki Numata Takeshi Oshima 《Journal of sports sciences》2016,34(20):2011-2017
Changes in muscle activity were evaluated by positron emission tomography–computed tomography (PET–CT) after performing part 2 of the Fédération Internationale de Football Association’s 11+ programme (11+) for 4 weeks. Eleven males performed part 2 of the 11+ for 20 min before and after 37 MBq of 18F-fluorodeoxyglucose (FDG) was injected intravenously. PET–CT images were obtained 50 min after FDG injection. The participants were then instructed to perform part 2 of the 11+ 3 times per week for 4 consecutive weeks, after which another set of PET–CT images was obtained following the same procedure. Regions of interest were defined within 30 muscles. The standardised uptake value (SUV) of FDG by muscle tissue per unit volume was calculated, and FDG accumulation was compared between pre- and post-training PET–CT results. Performing part 2 of the 11+ for 4 weeks increased mean SUV in the sartorius, semimembranosus, biceps femoris, abductor hallucis, and flexor hallucis brevis muscles (P < 0.05). In conclusion, routinely performing part 2 of the 11+ for 4 weeks increased glucose uptake related to muscle activity in the hamstrings and hallux muscles. We speculate that there is some possibility of this change of muscle activity contributing to a decrease in sports-related injuries. 相似文献