Official Journal of the Japan Wood Research Society
Table 1 Relationships between the calculated strains (\({\varepsilon _x}\), \({\varepsilon _y}\), \({\gamma _{xy}}\)) and the artificially imposed strains (\({\varepsilon _{\text{n}}}\), \({\gamma _{\text{n}}}\))
Artificially imposed strain \({\varepsilon _{\text{n}}}\), \({\gamma _{\text{n}}}\) (%) | Mean | ||||||||
|---|---|---|---|---|---|---|---|---|---|
\(- 0.94\) | \(- 0.83\) | \(- 1.04\) | \(- 5.00\) | \(- 10.00\) | \(- 15.00\) | \(- 20.00\) | \(- 25.00\) | ||
Mean ± SD (%) (n = 25) | |||||||||
\(\overline {{{\varepsilon _x}}} \pm {\text{SD}}\_{\varepsilon _x}\) | \(- 0.90 \pm 0.21\) | \(- 4.96 \pm 0.44\) | \(- 10.02 \pm 1.32\) | \(- 14.95 \pm 2.25\) | \(- 19.35 \pm 3.39\) | \(- 24.44 \pm 4.99\) | |||
\(\overline {{{\varepsilon _y}}} \pm {\text{SD}}\_{\varepsilon _y}\) | \(- 0.78 \pm 0.17\) | \(- 5.06 \pm 0.52\) | \(- 10.10 \pm 1.14\) | \(- 14.93 \pm 1.90\) | \(- 20.08 \pm 2.92\) | ||||
\(\overline {{{\gamma _{xy}}}} \pm {\text{SD}}\_{\gamma _{xy}}\) | \(- 1.00 \pm 0.34\) | \(- 5.07 \pm 0.91\) | \(- 10.12 \pm 1.72\) | \(- 15.17 \pm 2.70\) | \(- 20.22 \pm 3.70\) | \(- 25.37 \pm 5.10\) | |||
Coefficient of variation (%) | |||||||||
\({\text{CV}}\_{\varepsilon _x}={\text{SD}}\_{\varepsilon _x}/\overline {{{\varepsilon _x}}} \times 100\) | \(- 24\) | \(- 9\) | \(- 13\) | \(- 15\) | \(- 18\) | \(- 20\) | \(- 16\) | ||
\({\text{CV}}\_{\varepsilon _y}={\text{SD}}\_{\varepsilon _y}/\overline {{{\varepsilon _y}}} \times 100\) | \(- 20\) | \(- 10\) | \(- 11\) | \(- 13\) | \(- 15\) | \(- 14\) | |||
\({\text{CV}}\_{\gamma _{xy}}={\text{SD}}\_{\gamma _{xy}}/\overline {{{\gamma _{xy}}}} \times 100\) | \(- 34\) | \(- 18\) | \(- 17\) | \(- 18\) | \(- 18\) | \(- 20\) | − 21 | ||
Error rate (%) | |||||||||
\({\text{ER}}\_{\varepsilon _x}=(\overline {{{\varepsilon _x}}} - {\varepsilon _{\text{n}}})/{\text{~}}{\varepsilon _{\text{n}}} \times 100\) | \(- 4.00\) | \(- 0.81\) | \(0.16\) | \(- 0.33\) | \(- 3.27\) | \(- 2.23\) | \(- 1.75\) | ||
\({\text{ER}}\_{\varepsilon _y}=(\overline {{{\varepsilon _y}}} - {\varepsilon _{\text{n}}})/{\text{~}}{\varepsilon _{\text{n}}} \times 100\) | \(- 6.62\) | \(1.19\) | \(0.97\) | \(- 0.50\) | \(0.41\) | \(- 0.91\) | |||
\({\text{ER}}\_{\gamma _{xy}}=(\overline {{{\gamma _{xy}}}} - {\gamma _{\text{n}}})/{\text{~}}{\gamma _{\text{n}}} \times 100\) | \(- 3.99\) | \(1.53\) | \(1.17\) | \(1.10\) | \(1.12\) | \(1.48\) | \(0.40\) | ||