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11.
The purpose of the study was to investigate the effect of different kicking modality, i.e., erratic-dynamic target (EDT) versus static target (ST) on the performance of the roundhouse kick in two groups of taekwondo athletes of different skill level. Three-dimensional analysis and surface electromyography (SEMG) analysis were performed on 12 (Group A: six sub-elite, Group B: six elite) athletes to investigate muscle co-activation pattern under two conditions, i.e., EDT versus ST. In the results, the muscle recruitment ratio of the agonistic muscles was higher for Group A, whereas Group B had higher recruitment ratio for antagonist muscles. Overall, the co-activation index (CI) of hip joints appeared higher in the extensors for Group A, whereas higher CI was observed in flexor muscles for Group B with comparatively higher CI during EDT condition than ST condition. Higher value of CI was observed in flexor muscles of the knee joints among Group A during EDT conditions, in contrast, higher CI in the extensor muscles was observed among Group B during ST conditions. In conclusion, the study confirmed that erratic-dynamic movements of target could change the movement coordination pattern to maintain the joint stability of participants.  相似文献   
12.
Modern organized international badminton began with the founding of the International Badminton Federation (IBF) in 1934, consisting of nine founding member associations. The inaugural men’s Thomas Cup tournament began in 1948 when 10 countries took part. Malaya won the Cup four times in 1949, 1952, 1955, and 1967. When Indonesia took part in the tournament for the first time in 1957, there were 19 competing teams. Indonesia won the triannual tournament seven times from 1957 to 1979. Throughout the 11 Thomas Cup tournaments, only two Asian countries have won the Cup. The only European country, Denmark, qualified to play in the finals five times without a single win. Malaya (later known as Malaysia), Indonesia, and Denmark became leading Thomas Cup teams because they produced singles and doubles players that won many All-England Badminton Championship titles. The winners of these titles were generally considered the world champions. The key sources of information for this research consisted of the IBF annual statutes for listing of participating nations, tournament programmes, and rare specialized books on badminton and the Thomas Cup competition. English language newspapers such as the Singapore Free Press and the Straits Times published historical match results for checking the secondary data collected.  相似文献   
13.
Based on a study conducted in a core module of the Postgraduate Diploma in Education programme at the National Institute of Education (Singapore), this paper provides an account of the perceptions and experiences of pre-service teachers on the roles of their tutors in the online discussion board. The research methods included a questionnaire survey, two focus group interviews and an analysis of the discussion records. The findings suggest that there are gaps between the experiences and perceptions of the pre-service teachers on the roles of their tutors. These identified gaps have various implications for the role of the online tutor in practice: setting meaningful tasks; guiding participants in the 'technicalities' of online discussion; participating actively in discussions by answering queries, providing feedback and posing conflicting views to elicit thinking/reflection; keeping the discussion focused; drawing conclusions and providing content expertise; and recommending resources for extension of learning.  相似文献   
14.
The aim of this study was to compare the pre- and post-impact three-dimensional kinematics of the ball and racquet during first and second serves performed by elite tennis players. Data were collected from four male and four female right-handed professional players during competition using two high-speed cameras (200 Hz). For each player, one first serve and one second serve from the 'deuce' or right service court that landed within the specified target area were analysed. To test for significant differences between the first and second serves, Wilcoxon tests (P < or = 0.05) were performed on selected parameters. The results indicate that the ball travelled forward and to the left during the flight phase of the toss in all but one trial. The average pre-impact ball forward location for the first serve was significantly more in front and had a higher associated forward ball velocity than the corresponding values for the second serve. On average, the decrease in post-impact ball speed from the first to the second serve was 24.1%. No significant differences between the first and second serves were found in the pre-impact racquet head speed and orientation, which was represented as a unit vector perpendicular to the racquet face. The major adjustments made by the players when going from the first to second serve were a decrease in pre-impact ball forward location (P < or = 0.01) and an increase in the pre-impact racquet vertical and lateral velocities (both P < or = 0.05). This implies that the players tossed the ball closer to the body and imparted topspin and sidespin on the ball by changing the racquet vertical and lateral velocities when going from the first to the second serve.  相似文献   
15.
Electroosmotic flow (EOF) with two or more fluids is commonly encountered in various microfluidics applications. However, no investigation has hitherto been conducted to investigate the hysteretic or flow direction-dependent behavior during the displacement flow of solutions with dissimilar ionic species. In this investigation, electroosmotic displacement flow involving dissimilar ionic solutions was studied experimentally through a current monitoring method and numerically through finite element simulations. The flow hysteresis can be characterized by the turning and displacement times; turning time refers to the abrupt gradient change of current-time curve while displacement time is the time for one solution to completely displace the other solution. Both experimental and simulation results illustrate that the turning and displacement times for a particular solution pair can be directional-dependent, indicating that the flow conditions in the microchannel are not the same in the two different flow directions. The mechanics of EOF hysteresis was elucidated through the theoretical model which includes the ionic mobility of each species, a major governing parameter. Two distinct mechanics have been identified as the causes for the EOF hysteresis involving dissimilar ionic solutions: the widening/sharpening effect of interfacial region between the two solutions and the difference in ion concentration distributions (and thus average zeta potentials) in different flow directions. The outcome of this investigation contributes to the fundamental understanding of flow behavior in microfluidic systems involving solution pair with dissimilar ionic species.  相似文献   
16.
During the Japanese occupation of British Malaya and Southeast Asia from the years 1942 to 1945 there were reports of POWs being allowed to play cricket, football, rugby and basketball, as told by Kevin Blackburn in The Sportsmen of Changi published in 2012. This research about the sporting lives of a Governor and male European internees at Singapore's Changi prison is likely to be first detailed research on this topic. The authors depended mainly on four published diaries and 262 issues of the men's camp newspaper, Changi Guardian, to account for the male internees' casual and competitive cricket, football, hockey, volleyball, badminton, tennis and boxing matches that were played during internment. The Japanese Military Administration allowed the male internees to organize their daily lives and play games that they indulged in during the pre-War period as the British dominated the Singapore Cricket Club, Penang Cricket Club and Perak Club. The internees were able to play the various games and matches in spite of the limited food and sparse facilities. Many of the cricket and football games that were played were organized as inter-state, inter-club or league matches. These games were played with improvized equipment and rules.  相似文献   
17.
A novel microfluidic device which consists of two stages for particle focusing and separation using a viscoelastic fluid has been developed. A circular capillary tube was used for three-dimensional particle pre-alignment before the separation process, which was inserted in a polydimethylsiloxane microchannel. Particles with diameters of 5 and 10 μm were focused at the centerline in the capillary tube, and the location of particles was initialized at the first bifurcation. Then, 5 and 10 μm particles were successfully separated in the expansion region based on size-dependent lateral migration, with ∼99% separation efficiency. The proposed device was further applied to separation of MCF-7 cells from leukocytes. Based on the cell size distribution, an approximate size cutoff for separation was determined to be 16 μm. At 200 μl/min, 94% of MCF-7 cells were separated with the purity of ∼97%. According to the trypan blue exclusion assay, high viability (∼90%) could be achieved for the separated MCF-7 cells. The use of a commercially available capillary tube enables the device to be highly versatile in dealing with particles in a wide size range by using capillary tubes with different inner diameters.  相似文献   
18.
The purpose of this research is to investigate the factors that affect undergraduates' behavioral intention to use digital library among the private universities in Malaysia. The target respondents are undergraduates from Malaysian private universities. Questionnaires were distributed among 500 undergraduates through either online or face-to-face method. Reliability test, normality test, Pearson Correlation Coefficient analysis, and Multiple Linear Regression (MLR) were carried out for data analysis. Performance expectancy, social influence, facilitating conditions, hedonic motivation, habit, and information quality had a positive and significant association with behavioral intention to adopt a digital library except for effort expectancy. This research successfully reinforced that the inspiration to ameliorate Unified Theory of Acceptance and Use of Technology 2 (UTAUT 2) by synthesis of Information Systems Success Model (ISSM). This proposed framework with a combination of ISSM and UTAUT 2 has enhanced the fitness of UTAUT 2. Universities that have yet to implement digital library can comprehend undergraduates' needs better by considering all the significant factors to develop a digital library. The universities with the digital library may also notice the important features of the existing digital library that should be maintained and upgraded constantly so that they can fulfil undergraduates' requirements.  相似文献   
19.
Journal of Science Education and Technology - In this study, a new physics education programme is specifically developed for a famous theme park in Hong Kong to provide community-based science...  相似文献   
20.
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