Biomechanical Analysis of Body Movement During Skiing Over Bumps

Maintenance of balance of the skier's body is one of the most important and basic techniques in skiing on slopes of various conditions. However, skiers, especially beginners are likely to lose their balance on an uneven terrain with dips and swells. In order to keep his balance during skiing on an uneven terrain, it seems to be important for a skier to avoid receiving impulse from the snow surface. Some investigations have been conducted about maintenance of balance of body during skiing over artificially constructed bumps by means of electromyography (Miyashita and Sakurai, 1979), electrogoniometry (Iizuka and Miyashita, 1979) and cinematography (Miyashita and Sakurai, 1979, Iizuka and Miyashita, 1979, Sodeyama et al., 1979 and Ikegami et al. 1985). However, there is no research to try to measure force or acceleration acting on the skier's body during running over bumps. Therefore the purpose of this study is to measure force acting on skier's body by analyzing the movement of skier's body mechanically as well as kinematically, and to find out essential motions to maintain the balance of skier's body against rapid change of force acting from snow surface while skiing over bumps on a straight downhill run

Observation of the decay mode K_L -> pi^+ pi^- e^+ e^-

We report on results of an experimental search for the K_L -> pi^+ pi^- e^+ e^- decay mode. We found 13.5 +- 4.0 events and determined its branching ratio to be (4.4 +- 1.3(stat) +- 0.5(syst))*10^{-7}. The result agrees well with the theoretical prediction.Comment: 9 pages, 6 eps-figures, LaTeX2e, graphicx package, submitted to Physics Letters

A THREE-DIMENSIONAL CINEMATOGRAPHIC ANALYSIS OF THE BASEBALL PITCH

Pitching is one of the most important aspects of the game of baseball. However, only a small number of quantitative biomechanical studies have been reported (Feltner & Dapena, 1986). Specifically, there have been few studies of the motion of the forearm and wrist joints during a pitching action. The purpose of this study is to record the changes in angles and angular velocities of the shoulder, elbow, radioulnar and wrist joints during a baseball pitch. In this study, three dimensional (3-D) high-speed cinematography was used to record the fastball pitches of varsity baseball pitchers

A Three-Dimensional Cinematographic Analysis of Badminton Strokes

Badminton and tennis are two of the most popular striking activities, Broer & Zernicke (1979) stated that one evident difference between the two sports skills was the degree to which the wrist snap was used. They stated that the wrist snap just before impact was the most essential action of badminton strokes and it was enabled by the lightness of the badminton racket. Gowitzke & Waddell (1979) analyzed forehand and backhand smash strokes, representative of the most powerful overhead striking motions in badminton. They concluded that medial rotation of the humerus at the shoulder joint and pronation of the forearm at the radio-ulnar joints were the principal contributing movements for the forehand smash, In badminton strokes, many joint actions in three planes are involved in the striking motion, so that two-dimensional procedures are insufficient for analyzing the stroke motion of badminton. Relatively small numbers of biomechanical studies have been completed on kinematic parameters of badminton strokes. Quantitative studies with threedimensional procedures have been even more limited. The purpose of this investigation was to determine the changes of joint angles of the upper body during the execution of the drop shot and the cut shot in badminton using three dimensional cinematography

Scalability of spin FPGA: A Reconfigurable Architecture based on spin MOSFET

Scalability of Field Programmable Gate Array (FPGA) using spin MOSFET (spin FPGA) with magnetocurrent (MC) ratio in the range of 100% to 1000% is discussed for the first time. Area and speed of million-gate spin FPGA are numerically benchmarked with CMOS FPGA for 22nm, 32nm and 45nm technologies including 20% transistor size variation. We show that area is reduced and speed is increased in spin FPGA owing to the nonvolatile memory function of spin MOSFET.Comment: 3 pages, 7 figure

Experimental search for the decay mode K_L -> pi^0 gamma e^+ e^-

We report on results of a search for the decay mode K_L -> pi^0 gamma e^+ e^- conducted by the E162 experiment at KEK. We observed no events and set a 90% confidence level upper limit of Br(K_L -> pi^0 gamma e^+ e^-)< 7.1x10^{-7} for its branching ratio. This is the first published experimental result on this decay mode.Comment: 10 pages, 4 figures, submitted to Physics Letters