变换器械训练法在体工队链球训练中的应用

链球是田径运动中的投掷项目之一,属于一种可增长力量型的运动,对运动员的协调性和高速度旋转中身体的平衡度要求较高。在体工队链球训练的过程中,应用变换器械训练法能够帮助体工队运动员更好的掌握身体的协调性,使运动员达到身体素质和技能素质的快速提升,从而在各类比赛活动中,获得更加优异的成绩。     

巧用摩擦角解摩擦平衡题

摩擦角在工程力学中有广泛的应用，是工程力学的重要概念，如果在有关摩擦平衡的问题上巧用摩擦角处理却能收到意想不到的效果，它可以简化受力，减少运算，提高处理问题的效率。下面针对摩擦角的概念和应用作以下简要介绍。     

Skin friction of various surfaces

Measurements were made of the skin friction of various fabrics and surfaces due to interest in the reduction of the skin friction of Zeppelin outer cover.A machine was designed and constructed using Couette type of flow for the purpose of making the measurements. Results obtained with the machine are in general agreement with wind tunnel results.It was found that a smooth surface free from nap, whatever the material, approaches a limiting value for skin friction, and that as a surface becomes smoother any improvement in skin friction becomes increasingly hard to obtain.The results are illustrated by curves.     

浅谈液压破碎锤在石方开挖工程中的应用

随着以人为本安全工作及环保工作的深入开展、市场的激烈竞争,选取适宜科学的施工工艺方法以保障工程安全、质量进度是值得深入研讨的。     

The nature of static friction

The factors concerned in friction are discussed, together with a review of the limitations of the various approaches heretofore used. A more satisfactory view of the basic cause of static friction is developed in relation to modern experimental knowledge by considering the pertinent factors in systems having ideal surfaces, then relating this discussion to conditions in the best obtainable practical situation.