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21.
采用单元教学法对高水平运动员进行文化课教学的探讨   总被引:2,自引:0,他引:2  
针对高水平运动员在接受文化教育中所面临的“时间不够”的难题,着重从改革教学方法入手进行分析与研究,摸索出单元教学法是解决这一难题的有效途径。  相似文献   
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This article is concerned with the control of a Semi-Active suspension system of a 7DOF Full Vehicle model, equipped with four Electro Rheological (ER) dampers, taking into account their incipient dissipativity constraints. Herein, a real-time, fast, advanced control structure is presented within the Model Predictive Control framework for Linear Parameter Varying (LPV) systems. The control algorithm is developed to provide a suitable trade-off between comfort and handling performances of the vehicle in a very limited sampling period (Ts=5ms), in view of a possible realtime implementation on a real vehicle. The control structure is tested and compared to other standard fast control approaches. Full nonlinear realistic simulation results illustrate the overall good operation and behaviour of the proposed control approach.  相似文献   
24.
This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller.  相似文献   
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Many very young children attend early care and education programs, but current information about the quality of center-based care for toddlers is scarce. Using 2 observation instruments, the Infant/Toddler Environment Rating Scale–Revised (ITERS-R) and the Classroom Assessment Scoring System, Toddler Version (CLASS-Toddler), 93 child care classrooms for toddlers across the state of North Carolina, representing a range of quality, were assessed to determine overall quality, and associations between observed quality and teachers' ratings of child behavior problems and competence outcomes using the Brief Infant Toddler Social Emotional Assessment. Research Findings: Findings indicated that overall, toddler classrooms were rated as being of moderate quality. Associations between observed quality and teacher-reported child behavior problems and competence outcomes indicated that CLASS-Toddler ratings were positively associated with fewer behavior problems; specifically, children in classrooms with higher levels on the CLASS-Toddler domains of Emotional and Behavioral Support as well as Engaged Support for Learning were reported to have fewer behavior problems. Similarly, the ITERS-R subscales of Interaction and Listening and Talking were positively related to fewer reported behavior problems. Regression models showed that the CLASS-Toddler Emotional and Behavioral Support domain predicted differences in child behavior problems. Practice or Policy: Findings suggest the need for additional research related to very young children's experiences in center-based child care to examine associations between quality and child experiences and outcomes. Children's experiences over time need to be examined to understand how these early child care experiences are related to children's later school adjustment and performance. On a related note, professional development for teachers in toddler classrooms needs to be addressed in terms of preparing effective teachers for young children during the toddler developmental period.  相似文献   
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This autobiographical article explores the way one North American high school teacher's intuitive teaching principles developed over time. The author uses tennis as a metaphor to try to describe her feelings about the teaching process.  相似文献   
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All traumatic and overuse injuries occurring during an average period of 4 years (2002/09) in a group of 51 currently active road top-level cyclists were retrospectively registered through clinical interviews. Average age was 25.8 years. Average training and competition period was 28.3 ± 2.4 h a week. Only 8 cyclists (15.6%) were completely free from lesions during the period of study. The remaining 43 cyclists suffered a total of 112 lesions; however, 9 out of these were unrelated to their cycling practice. These 103 cycling-related injuries include 50 (48.5%) traumatic and 53 (51.5%) overuse injuries. Twenty-eight fractures were reported, the clavicle being the most frequently affected bone (11 cases). The 68.5% of overuse injuries were located in the lower limbs. Most overuse injuries (89.6%) occurred during the training period. According to the injury abbreviated scale (AIS), severe lesions were only found in 4 cases (8% of traumatic injuries). Overall injury rates were 0.50 per racer/year, 2.02 per studied racer, and 0.007 per 1000 km of training and competition. Active professional top-level cyclists are exposed to a high injury risk. According to the scarce previously published data the current study provides relevant information on the injury occurrence of still active top-level road cycling.  相似文献   
28.
The painting Proas Iluminadas (Illuminated Bows) by Benito Quinquela Martín is studied by Raman spectroscopy in order to analyse the technique and the pigments employed by the artist: ultramarine blue, carbon black, cadmium-sulphure based compounds for the hue of yellow, orange and red; also zinc white, barium yellow, massicot yellow and viridian were observed. The importance of using different excitation laser lines in the analysis of mixtures of pigments is highlighted. The Raman mapping analysis of cross section samples shows the way the artist composed the ground layer: a lead white stratum over a calcite one. It also allows distinguishing between a mixture of components and strata superposition, both presenting the same appearance under an optical microscope. This paper provides information about the materials and techniques used in a period of Argentine art not studied before from this point of view.  相似文献   
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The National Council for Accreditation of Teacher Education (NCATE) program review process increasingly emphasizes the importance of performance-based assessment of early childhood teacher preparation programs. As part of the effort to address performance-based assessment requirements, the teacher educator program described in this study examined students’ beliefs related to developmentally appropriate practice, attitudes toward children, and perceived competencies at different points in the program and upon graduation. One hundred eighteen students and 78 recent graduates participated. Results suggest that students’ beliefs are more consistent with developmentally appropriate practices and with a progressive or child-centered approach at later points in the program. In general, participants felt they were more competent in what they know about early childhood practices than in how they implement the practices. Students nearing completion of the program and those who had graduated reported that they knew more about early childhood practices than students enrolled in early courses in the program, and graduates felt they were more competent to implement early childhood practices than students not enrolled in the program. Results are discussed in terms of implications for examining teacher preparation programs.  相似文献   
30.
Research Findings: Using observational data gathered in 730 kindergarten classrooms in 6 states, the present study focuses on the quality of children's learning opportunities in kindergarten classrooms. Findings show that overall, children experience moderate to low levels of quality in the areas of classroom organization and instructional support in kindergarten. Results are also presented in comparison to children's experiences in the pre-kindergarten year. These comparisons indicate that kindergarten children spend a greater proportion of the school day in language arts, math, and whole-group instruction and less time in centers than they do in pre-kindergarten. An examination of predictors of kindergarten classroom quality indicated that program characteristics (i.e., adult–child ratio, length of school day) and teacher psychological variables (i.e., beliefs and depressive symptoms) were stronger predictors of classroom quality than were teacher experience and educational background. Practice or Policy: Findings are discussed in terms of implications for children's academic and social development in kindergarten as well as for kindergarten teacher preparation and development.  相似文献   
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