Voellmy’s (1955) method for computing the run-out distance of a snow avalanche includes an unsatisfactory feature: the a priori selection of a midslope reference where the avalanche is assumed to begin decelerating from a computed steady velocity. There is no objective criterion for selecting this reference, and yet the choice critically determines the computed stopping position of the avalanche. As an alternative, a differential equation is derived in this paper on the premise that the only logical reference is the starting position of the avalanche. The equation is solved numerically for paths of complex geometry. Solutions are based on two parameters: a coefficient of friction μ; and a ratio of avalanche mass–to–drag, M⁄D. These are analogous to the two parameters in Voellmy’s model, μ and ξH. Velocity and run-out distance data are needed to estimate μ and M⁄D to useful precision. The mathematical properties of two–parameter models are explored, and it is shown that some difficulties arise since similar results are predicted by dissimilar pairs of μ and M⁄D.

This study examined the maximum acceptable weight of carriage (MAWC) for young Taiwanese males experienced in manual load carriage tasks. The elements of the examined load carriage tasks included lifting a box from the floor to the waist height, turning around while holding the box, carrying the box at the waist height for a distance, lowering the box to the floor, turning around, and walking unloaded back to the original position. Subjects performed the load carriage tasks over different levels of carriage distance, frequency, box width (sagittal dimension), and handle according to a response surface design. The results showed that subjects' MAWC decreased with carriage distance, frequency and box width, while heart rate and rate of perceived exertion (RPE) increased with carriage distance, frequency and box width. The MAWC for box with handles was on average 1.5 kg more than that for box without handles, while the effects of handle on heart rate and RPE were very trivial.

This paper explores the computational problem of finding suitable numbers to use in a two-parameter model of snow avalanche dynamics. The two parameters are friction, μ, and a ratio of avalanche mass to drag, M/D. Given a path profile, and a maximum avalanche speed, then it is possible to compute unique values for u and M/D. If only the path profile and the stopping position are known, then it is possible to compute tables of pairs {μ, M/D} which can be tested as predictors of avalanche speeds. To generate these tables it is convenient to scale M/D in multiples of the total vertical drop of the path. The computations were tested on 136 avalanche paths. Values of {μ, M/D} were stratified, and certain values were rejected as unrealistic.

This study tested 29 young Taiwanese men and 31 young Taiwanese women to examine the effects of pulling type (one-handed and two-handed) and height (48 cm, 84 cm, 120 cm, and 156 cm) on maximum horizontal isometric pulling strengths. Analysis showed differences in pulling strength between one-handed and two-handed efforts were surprisingly small for free pulling postures. The pulling strength decreased significantly with pulling height. The highest pulling strength was approximately two to three fold the lowest pulling strength across the four pulling heights. The women's pulling strength was approximately 59% to 67% of men's pulling strength. The test-retest correlations for pulling strength were satisfactory. The correlations between pulling strength and subjects' anthropometry were not sufficiently high to justify the prediction of strength. Most correlations between strengths in any two different pulling conditions were high and significant.

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