浅谈运动处方的实施

综述了对运动处方的认识与理解 ;有氧运动是指 4～ 5min或更长时间进行的全身性的持续运动 ,强调运动强度和持续时间的组合和频率 ;局部肌肉运动分为动和静两种运动 ;注意最大肌力的比例和反复次数的结合 ;循环训练。

共生效应法是开展班级田径运动值得采用的一种方法

田径运动是各项体育开展的如何,首先要看它的田径运动的运动的基础,一个学校体育运动群众性和代表性。因此,学校理应是发展田径运动的摇篮。然而,这几年,受世俗偏见的影响,青少年对田径运动的兴趣被冷落,群众性的课外田径运动自然遇到不少困难,我们采用共生效应法,推动于一个班级田径运动的开展,取得了良好的效果。

夜光反射纤维

美国制造了一种新型纤维,即夜光反射纤维。目前已将这种纤维制成了用于夜间室内活动的运动衣、背包、短裤、外套以及其他用具或服装等物品。这种纤维具有一种能反射光线的抛光体—微型玻璃珠。用这种纤维制成的用具能使赛跑、竞走、自行车运动员在夜间活动时,更容易看清楚。实验证明,在普通光线下。

Simulation and Analysis of Fiber Motion in Condensing Zone of Compact Spinning with Lattice Apron

To get fiber motion in condensing zone of compact spinning,velocity of this area is achieved by simulation,and then a bead-elastic rod fiber model is established.Based on simulation and dynamic analysis on this zone,governing equations are constructed and Runge-Kutta approach is used.Lastly,trajectories of fibers are calculated by specially designed Matlab procedure according to the principles mentioned above.Results show that fiber motions at different initial positions are different;X-axis velocity component makes fibers gathering on sides of suction slot;Y-axis airflow gets fibers gradually close and then stick to the surface of lattice apron.Fiber motions also reflect that the compact spinning process in condensing zone can be divided into three parts:fast convergence zone,adjustment convergence zone,and steady convergence zone.

Molecular dynamics study of viscosity of aqueous NaCl solution confined in nanoscale channels

A physical model of bulk-nanochannel-bulk with buffer baths is built up using nonequilibrium molecular dynamics （MD） simulation to study the effects of vibrating silicon atoms on the viscosity of aqueous NaCl solutions confined in the nanochannel. The simulation is performed under different moving speeds of the upper wall, different heights and different surface charge densities in the nanochannel. The simulation results indicate that with the increase in the surface charge density and the decrease in the nanochannel height and the shear rate, the vibration effect of silicon atoms on the shear viscosity of the confined fluid in the nanochannel cannot be ignored. Compared with still silicon atoms, the vibrating silicon atoms result in the decrease in the viscosity when the height of the nanochannel is less than 0.8 nm and the shear rate is less than 1.0 ×10^11 s^-1, and the effect of the vibrating silicon atoms on the shear viscosity is significant when the shear rate is small. This is due to the fact that the vibrating silicon atoms weaken the interactions between the counter-ions （Na^＋ ） and the charged surface.

L2 Syntactic Alignment in the Reading-Writing Integrated Continuation Task: Evidence From Chinese EFL Learners’ Description of Motion Events

This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construction with manner verbs. Ninety Chinese students were assigned to either of the two experimental groups or a control group, and they all experienced a pretest, an alignment phase and a posttest. In the alignment phase, the two experimental groups completed a reading-writing integrated continuation task but in different modes. For the multi-turn mode,participants reconstructed a picture story by continuing the episodes extracted from the story with one episode presented and continued at a time;for the single-turn mode, the first half of the same picture story was presented as a chunk, and then participants read and continued it. Results show that L2 learners aligned with the target structure in completing the story, and the alignment effect was retained in the posttest conducted after a delay of two weeks. Moreover, syntactic alignment was modulated by task mode with the multi-turn group exhibiting stronger immediate and longterm alignment effects. We conclude that the continuation task is a fruitful context for L2 structural alignment, and the magnitude of alignment effect hinges on interactive intensity.

Nonlinear Dynamic Analysis of the Whole Vehicle on Bumpy Road

Through the research into the characteristics of 7-DoF high dimensional nonlinear dynamics of a vehicle on bumpy road, the periodic movement and chaotic behavior of the vehicle were found.The methods of nonlinear frequency response analysis, global bifurcation, frequency chart and Poincaré maps were used simultaneously to derive strange super chaotic attractor.According to Lyapunov exponents calculated by Gram-Schmidt method, the unstable region was compartmentalized and the super chaotic characteristic of ...

Using physical examinations to estimate age in elementary school children:A Chinese population-based study

Background:Designing a simple and accessible approach to age estimation in children and youth is a great challenge in the fields of sports and physical activity(PA).This study was designed to develop and validate a physical-examination-based method of estimating age in young children.Methods:In a cross-sectional study conducted in 2014,we performed physical examinations and assessed PA among 14,970 elementary school children 7–12 years old in Shanghai,China.Additional biological information on the children's height and birth date was ascertained through their parents.Two indicators were applied to develop a gender-specific age estimation equation:The percentage of predicted mature height(PPMH) and the Tanner stage.The equation was validated through a k-fold cross-validation approach.To check for estimation accuracy,the association between the discrepancy of estimated age(EA) and chronological age and PA was examined.Results:The gender-specific equations of EA were as follows:EA_(boy) = –6.071 + 6.559 Tanner 2 + 13.315 Tanner 3 + 14.130 Tanner 4 + 0.190 PPMH – 0.071 Tanner 2 × PPMH – 0.146 Tanner 3 × PPMH – 0.155 Tanner 4 × PPMH;EA_(girl) = –4.524 – 1.251 Tanner 2 + 2.504 Tanner 3 + 8.752 Tanner 4 + 11.893 Tanner 5 + 0.158 PPMH + 0.017 Tanner 2 × PPMH – 0.024 Tanner 3 × PPMH – 0.087 Tanner 4 × PPMH – 0.118 Tanner5 × PPMH.The mean absolute error was 0.60 years for boys and 0.59 years for girls.The discrepancy score was negatively and weakly associated with self-reported moderate-to-vigorous PA in both genders(r_(boy) = –0.09,p < 0.001;r_(girl) = –0.12,p < 0.001).Conclusion:Findings suggest that physical examinations could provide a valid and reliable approach for estimating age in young Chinese children.

Integral Operator Solving Process of the Boundary Value Problem of Abstract Kinetic Equation with the First Kind of Critical Parameter and Generalized Periodic Boundary Conditions

In this paper the concepts of the boundary value problem of abstract kinetic equation with the first kind of critical parameter γ 0 and generalized periodic boundary conditions are introduced in a Lebesgue space which consists of functions with vector valued in a general Banach space, and then describe the solution of these abstract boundary value problem by the abstract linear integral operator of Volterra type. We call this process the integral operator solving process.

步法的重要元素——分腿垫步

网球运动由各种基本技术组成,而这些基本技术又都包含了一连串的动作。网球场上,没有一次击球是在完全相同的情况下进行,场上情况千变万化,需要针对场上不同情况反复使用各项基本技术,将这些基本技术有机地连接在一起的就是步法。其中分腿垫步可称得上是最为重要的元素之一。

跖管综合症的病因与治疗

跖管综合症,多见于跑跳过多的运动爱好者和从事跑跳项目的运动员。它的发病原因和病理是:跑跳过多的运动爱好者和从事跑跳运动的运动员,在过多的跑跳中,足过度地跖屈和背伸活动,使踝关节内侧下方的骨性纤维管(跖管)内的肌腱。

Incipient motion of sediment by waves

In this paper, the forces acting on sediment particles are analyzed in all the aspects. Considering the cohesive force between particles, the additional static water pressure induced by the solid-body characteristics of film water and the inertia force of waves, a unified formula of the incipient motion for both coarse and fine particles is defined. The formula can reflect the variation in the initial velocity of fine particles with the volume weight of sediment. The verification of the formula is carried out by use of both experimental data and field observation data accumulated by experts at home and abroad. The verification shows that the formula expresses the law governing the incipient motion of sediment of all particle sizes inclusive of natural sediment and light-weight materials, and thus a basic formula for the study and solution of sediment problems in estuarine and coastal regions is provided.

Determination of Euler parameters of Philippine Sea plate and the inferences

Euler vectors of 12 plates, including Philippine Sea plate (PH), relative to a randomly fixed Pacific plate(PA) were determined by inverting the 1122 data from NUVEL-1 global plate motion model, earthquake slip vectors along Philippine Sea plate boundary, and GPS observed velocities. Euler vectors of Philippine Sea plate relative to adjacent plates are also gained. Our results are well consistent with observed data and can satisfy the geological and geophysical constraints along the Caroline(CR)-PH and PA-CR boundaries. Deformation of Philippine Sea plate is also discussed by using the plate motion Euler parameters.

An orbital motion study of globular cluster NGC6205

The positions and absolute proper motions of 264 stars in the field of about 70′ x 70′ around the globular cluster NGC6205 were determined. In the astrometric reduction, three early and three late epoch plates taken with the 40-cm refractor at Shensan, Shanghai, China, were used, with the epoch span of 73 a. The reduction was done using the central overlapping method, with 5 Hipparcos stars and 38 Tycho-2 stars as reference stars. Based on the reduced data of proper motion, the membership probabilities of the sample stars were determined. An absolute proper motion of the cluster of(1.49±0.36)mas a-1 in R.A. and (3.06±0.35)mas a-1 in Decl. was obtained. From this proper motion, together with distance and radial velocity data, we derived the space motion of NGC6205 and the orbit of the cluster in the Galaxy via numerical integration.

Disturbance rejection and performance enhancement of perturbed tri-stable energy harvesters by adaptive finite-time disturbance observer

Tristable energy harvesters(TEHs)have been proposed to achieve broad frequency bandwidth and superior low-frequency energy harvesting performance.However,due to the coexistence of three potential wells and the sensitivity to system conditions and external disturbances,the desired high-amplitude inter-well oscillation in the TEHs may be replaced by the chaotic or intra-well oscillations with inferior energy output.Specifically,the chaos has an unpredictable trajectory and may cause system damages,lessen the structural durability as well as require a more complicated circuit for power management.Therefore,in this paper,we firstly propose an adaptive finite-time disturbance observer(AFTDO)for performance enhancement of TEHs by detecting the external disturbances that induce the chaos,and reject them for the recovery of the desired inter-well motion.The proposed AFTDO eliminates the need to know in advance the upper bounds of imposed perturbations in conventional observers by means of the proposed adaptive protocols,leading to the higher efficacy of estimation.The mathematical model of the piezoelectric TEH system and the AFTDO is provided.To demonstrate the effectiveness of the AFTDO,a series of numerical simulations have been performed.Results show that for both cases with sinusoidal and impulsive disturbances,the AFTDO can successfully track the trajectories of the disturbance signals with the adaptive gain,and reject the disturbance to enable the TEH to sustain the periodic inter-well oscillation with effective energy harvesting performance.