The collisions of elastic bar and elastic beam are treated analytically. It is already known that the collision phenomena of bar and beam will constitute form from only one time collision pattern to two or more intermittent type of collision patterns. and these patterns are determined by 1) mass ratio m_1/m_2, 2) natural-frequency ratio in the first-order mode f_<11>/f_<21>(or n_<11>/n_<21>), and 3) collision position ratio lp/l_2. In this paper, The influence of the boundary of a beam was investigated about the phenomena in which the number of times of a collision is 1 time, from the coefficient of restitution, the impact-force peak value, and the impact-force pattern. We studied analytically how a variation of the boundary condition of a beam (both-ends are supported beam, both-ends are clamped beam, one end clamped the other end free beam) would influence collision phenomena. The bar and beam to be used were unified and the variation was investigated by changing only a boundary condition. At last the relation between the μ_1/n_<11> value and the elastic energy of bar was considered analytically.

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We introduce our newly developed running watch equipped with heart rate monitor (ASICS AH01). The watch equipped with a function to estimate an AT heart rate (AT is an abbreviation for "Anaerobic Threshold". It refers to the point at which one's body transitions from aerobic to anaerobic exercise as the exercise intensity increases.). Also the watch is equipped with three attractive functions - Estimate of marathon finish time, Measurement condition checking function and Target heart rate zone function.

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