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Tattering of flags under controlled conditions

1966; Elsevier BV; Volume: 3; Issue: 3-4 Linguagem: Inglês

10.1016/0002-1571(66)90025-2

1878-2949

Nick Rutter,

Sports Dynamics and Biomechanics

The value of the textile flag as an index of exposure is examined under controlled conditions. Methods for recording reduction in material are compared, factors affecting tatter are examined and estimates are made of reliability of the technique. Weight and, secondly, area loss are the most reliable measures but nothing is gained by combining these. Water in the material and the development of a protective fray each affect tatter, which is therefore not a function of wind alone. The regressions of tatter y over 90 min on windspeed x are given by: log y = −0.1708+0.0245 x (for wet flags) and y = −0.284+0.1246 x (for dry flags) tatter being assessed as percentage weight loss from the original flag. Reliability is good under wet and dry conditions separately and when tatter is averaged over successive exposures, but individual observations are shown to be unreliable, especially at high windspeeds. Consequently the textile flag is thought to have limited application in biological studies.