排序方式： 共有16条查询结果，搜索用时 15 毫秒
1.
Donald Merriman Robin S. Codding Georgiana Shick Tryon Takuya Minami 《Psychology in the schools》2016,53(5):457-470
Research on the effectiveness of homework provides ample evidence that homework has a positive effect on learning, particularly for secondary students. Unfortunately, the rate of consistent homework completion for students, with and without disabilities, is low. This study used a between‐groups design to examine the differential effectiveness of coaching, a self‐management intervention, compared with the local treatment‐as‐usual (homework center) on improving the homework completion of 50 middle school students (Grades 6 to 8) with and without disabilities who were having substantial difficulty with homework. Results indicated that both group coaching and homework center (treatment‐as‐usual) were effective in significantly decreasing homework problems, with no clear indication that one intervention was, overall, superior to the other. However, preliminary analyses suggest that these interventions might be differentially effective as a function of disability status. 相似文献
2.
用于钢筋混凝土受弯构件补强加固的碳纤维织物的力学性能 总被引：1，自引：0，他引：1
讨论了用以测定碳纤维织物的抗拉强度及弹性模量等有关力学性能指标的相关方法 .对 5根碳纤维织物补强加固简支梁进行了试验研究和计算机模拟分析 ,试验数据与分析数据符合较好 ,说明碳纤维织物的实测力学性能指标可靠合理 .同时 ,在对试验数据进行分析整理的基础上 ,得出了碳纤维织物补强加固钢筋混凝土受弯构件正截面承载力的简化设计公式 . 相似文献
3.
4.
5.
结合运动员的工会组织全球化的趋势背景,以最早成立的全球化的运动员工会代表组织——国际职业足球运动员联盟（FIFPro）为中心,从1965年的早期着手开始,到近期的全球足球运动员工会成立,介绍该组织的历史以及在足球领域的立法和司法工作内容,并阐述超越体育运动框架的工会组织全球化的尝试以及今后的展望. 相似文献
6.
在发展中国家和一些有多种文化背景的发达国家里,民族数学已经获得了一定水平的发展动力。另一方面,起源于发达国家的批判性数学教育特别关注民族数学研究的批判性观点。在这种研究中,为了把民族数学和学校数学连接起来,并把它作为教育尝试,批判性数学教育和民族数学之间相辅相成的关系已被详细考虑。因此,为了通过互惠方式加强批判性本质和发展以民族数学为基础的数学教育,一个基础性的框架被建立。 相似文献
7.
Michihiro Hayashi Hiroshi Tachiya Naoki Asakawa Takuya Kawamura 《Journal of The Franklin Institute》2011,348(1):101-111
This study proposed a method for suppressing torques and consumed energy of manipulators considering an effect of inertial forces in order to achieve power-saved drive. The present paper describes the case that the start and end points of a work path of a manipulator are specified and the path between the points can be determined arbitrarily, which is so-called point-to-point (PTP) control. The proposed method determines both the initial pose of a manipulator and input motions of its joints so that the torque or consumed energy is suppressed. The input motion of the joint is expressed by a motion curve that indicates the time profiles of input displacements, velocities and accelerations. The proposed method determines the motion curve as a polynomial with appropriate coefficients. Those coefficients and their values are decided by a heuristic algorithm in order to suppress the input torques or consumed energy of a manipulator. The paper actually determines the power-saved drive motion of “PUMA560” by the proposed method and reveals its effectiveness. 相似文献
8.
Kazumichi Ae Sekiya Koike Takashi Kawamura 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(4):452-466
ABSTRACT The aim of this study was to investigate the kinetic functions of the lower limbs at different hitting-point heights to provide key information for improving batting technique in baseball players. Three-dimensional coordinate data were acquired using a motion capture system (250 Hz) and ground reaction forces were measured using three force platforms (1000 Hz) in 22 male collegiate baseball players during tee-batting set at three different hitting-point heights (high, middle, and low). Kinetic data were used to calculate joint torque and mechanical work in the lower limbs by the inverse dynamics approach. The peak angular velocity of the lower trunk about the vertical axis was smaller under the low condition. The joint torques and mechanical works done by both hip adduction/abduction axes were different among the three conditions. These results indicate that hip adduction/abduction torques mainly contribute to a change in the rotational movement of the lower body about the vertical axis when adjusting for different hitting-point heights. In order to adjust for the low hitting-point height which would be difficult compared with other hitting-point heights, batters should focus on rotating the lower trunk slowly by increasing both hip abduction torques. 相似文献
9.
Kazumichi Ae Sekiya Koike Norihisa Fujii Michiyoshi Ae Takashi Kawamura 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(3):283-296
The purpose of this study was to investigate effects of the ground reaction forces on the rotation of the body as a whole and on the joint torques of the lower limbs associated with trunk and pelvic rotation in baseball tee batting. A total of 22 male collegiate baseball players participated in this study. Three-dimensional coordinate data were acquired by a motion capture system (250 Hz), and ground reaction forces of both legs were measured with three force platforms (1,000 Hz). Kinetic data were used to calculate the moment about the vertical axis through the body’s centre of mass resulting from ground reaction forces, as well as to calculate the torque and mechanical work in the lower limb joints. The lateral/medial ground reaction force generated by both legs resulted in the large whole body moment about its vertical axis. The joint torques of flexion/extension of both hips, adduction of the stride hip and extension of the stride knee produced significantly larger mechanical work than did the other joint torques. To obtain high bat-head speed, the batter should push both legs in the lateral/medial direction by utilising both hips and stride knee torques so as to increase the whole body rotation. 相似文献
10.
Katsue Kawamura Masahiro Shinya Hirofumi Kobayashi Hiroki Obata Masumi Kuwata Kimitaka Nakazawa 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(3):399-410
This study evaluated baseball pitching accuracy using a variety of parameters to quantify pitching errors and analysed the validity of the accuracy measurements by comparing the outcomes of two small groups of pitchers. Several professional (n = 5) and high school (n = 8) pitchers threw 30 pitches each, including 20 fastballs and 10 breaking balls. To assess pitching accuracy, pitch locations relative to the catcher’s mitt (as the target) were evaluated with various parameters, including major/minor radius, an area of 95% confidence ellipse, absolute error, constant error and pitch location trajectory. Compared to the high school pitchers, the professional pitchers exhibited shorter major and minor radii in their 20 fastball pitches (p < 0.05), more accurate control in the lateral direction (p < 0.05), and shorter pitch location trajectories (p < 0.05). The evaluation methods presented in this study can objectively assess pitching accuracy and may thus provide useful coaching feedback with visual information. 相似文献