田径短跑摆腿技术动作分析与训练方法研究

短跑是一项竞争激烈且成绩提高缓慢的田径运动项目,现代短跑理论的侧重点已经从后蹬向摆腿进行转移.作为提高跑步速度的重要一环,如何提高运动员的摆腿速度和幅度,成为提升短跑运动员成绩的关键.因此,通过对传统和现代田径短跑理论的对比分析,阐述了现代短跑摆腿技术的特征,并从生物力学的角度分析了短跑摆腿训练方法,提出了切实可行的摆...     

对短跑摆动支撑技术生物学力学的再认识

后蹬不再是决定短跑成绩的主要推动力，摆动力才是提高跑速的关键，以髋为轴的摆腿技术是短跑技术的重点，正确的摆腿动作，可形成良好的着地支撑技术．突出支撑后蹬力在短跑中的重要性，势必破坏跑的周期性、协调性和连惯性，导致引入跳跃式跑动的歧途     

通过下肢肌电活动的对比探讨极限强度下摆腿力量训练的方法

本文运用运动生物力学分析和肌电观察对比的方法,找出了现有短跑运动员向前摆腿专门力量训练方法的缺陷,设计出一种运动形式和肌肉工作特点较为接近短跑摆腿动作的仰卧高台上摆腿的练习方法。     

大学短跑技术教学改革探析

运用文献资料、比较分析方法,针对现代短跑技术与训练的主要技术特征,跑动动作的节省化,完整技术的个体化特点,笔者认为以蹬摆结合技术是短跑技术的重中之重,"屈蹬式"后蹬后的快速折叠前摆有利于加大摆动腿前摆速度与幅度,对提高后蹬反作用力有帮助,有利于提高短跑速度。     

现代短跑技术教学与训练改革研究

研究将现代短跑技术理论应用于教学与训练实践的途径．提出并论述了“从腰发力,以髋带腿;快速高摆,积极扒地;步长适宜,加快频率”的技术要求,以及由“完整技术、变形技术、跑的专门练习和技术基础身体练习”４个层次组成的现代短跑技术训练内容体系．     

论短跑的跑蹬技术

回顾分析了短跑技术中的完全蹬伸技术、曲蹬技术和爬蹬技术在不同时期的演变过程.揭示了现代短蹬技术只是高速跑动中的一个自然连续的过程,是摆腿动作的延续,不需刻意地去作独立蹬伸动作.同时也对跑蹬技术和跑蹬技术的训练进行了论述.     

改进途中跑摆动腿技术对提高短跑速度的作用

百米跑是速度性项目,要想跑出人体的最大速度,首先要有正确的短跑技术。随着科技的发展,塑胶跑道的问世,现代短跑技术又有新的进展,从而促使对短跑技术理论作新的理解和探讨。在途中跑中后蹬不再是短跑成绩的主要决定因素,摆动腿积极前摆、后扒才是提高短跑速度的关键。实践证明,采用必要的专门性辅助练习能有效地改进途中跑摆动腿前摆后扒的技术,从而提高百米跑的专项成绩。     

改进途中跑摆动腿技术对提高短跑速度的作用

百米跑是速度性项目,要想跑出人体的最大速度,首先要有正确的短跑技术.随着科技的发展,塑胶跑道的问世,现代短跑技术又有新的进展,从而促使对短跑技术理论作新的理解和探讨.在途中跑中后蹬不再是短跑成绩的主要决定因素,摆动腿积极前摆、后扒才是提高短跑速度的关键.实践证明,采用必要的专门性辅助练习能有效地改进途中跑摆动腿前摆后扒的技术,从而提高百米跑的专项成绩.     

短跑伸髋高摆鞭打技术探析

从生物力学的角度对短跑中鞭打扒地、伸膝蹬地和伸髋高摆鞭打技术进行了分析,研究伸髋高摆鞭打技术的动作结构变化及其在短跑训练中的应用.     

短跑途中跑摆动腿动作技术对速度影响的分析

现代先进的短跑技术训练中提出加强摆动技术和“扒地”式着地技术的训练,短跑技术的重点已从后蹬转为摆动,训练方法和手段都相应地发生了变化。通过对短跑摆动腿动作技术的分析,提出有针对性地改进摆动技术方法,从而促进与提高后蹬效果、加快步频、增大步幅,达到提高短跑成绩的目的。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with