Table 1. Data on log concentration and the number of assortments in studies of mechanized CTL, which have reported total and forwarded log concentration as well as the number assortments at harvesting site and in loads. View in new window/tab. |

Table 2. Treatments included in the study (i.e. factor combinations) and their resulting levels of forwarded log concentration and distances driven between the first and the last loaded pile in a load. Each treatment was repeated three times, resulting in 24 observed loads in total. | |||

Factors | Forwarded log concentration (m ^{3}ob (100 m)^{–1}) | Distance driven between the first and the last loaded pile in a load (m) | |

Total log concentration (m^{3}ob (100 m)^{–1}) | Number of assortments in a load | ||

6.4 | 1 | 1.3 | 625 |

3 | 3.8 | 209 | |

5 | 6.4 | 125 | |

19.2 | 1 | 3.8 | 209 |

2 | 7.7 | 104 | |

3 | 11.5 | 70 | |

32.0 | 1 | 6.4 | 125 |

3 | 19.2 | 42 | |

m^{3}ob (100 m)^{–1} = solid m^{3} over bark per 100 m of the strip-road |

Table 3. Levels of significance (p-values) and level of explained variance (R^{2} adjusted values) obtained from the analysis of variance (ANOVA) of the main effects on the work elements’ time consumption and on the loading and unloading components. α is the number of assortments in a load, β is total log concentration on the strip-road and (αβ) is the fixed interaction effect. | |||||

Dependent variable | p-value | R^{2} (adj) (%) | Number of observations (n) | ||

α | β | (αβ) | |||

Time consumption for work elements (PMmin (m^{3}ob)^{–1}) | |||||

Work elements pooled | 0.006 | <0.001 | <0.001 | 89.8 | 18 |

Loading | <0.001 | 0.393 | 0.985 | 63.5 | 18 |

Driving while loading | <0.001 | <0.001 | <0.001 | 99.8 | 18 |

Unloading | <0.001 | 0.629 | 0.596 | 81.9 | 18 |

Driving while unloading | <0.001 | 0.538 | 0.538 | 88.6 | 18 |

Loading components | |||||

Time consumption for a loading stop (PMmin) | <0.001 | <0.001 | <0.001 | 67.5 | 378 |

Time consumption for distance driven between the first and the last loaded pile in a load (PMmin m^{–1}) | 0.182 | 0.132 | 0.074 | 32.9 | 18 |

Time consumption for a loading crane cycle (PMmin) | <0.001 | 0.076 | 0.721 | 11.5 | 526 |

Number of loading stops per load | <0.001 | <0.001 | <0.001 | 96.9 | 18 |

Number of loaded piles per stop | <0.001 | <0.001 | <0.001 | 69.2 | 378 |

Number of crane cycles per loading stop | <0.001 | <0.001 | <0.001 | 73.0 | 378 |

Number of loaded piles per crane cycle | 0.054 | <0.001 | 0.028 | 6.9 | 526 |

Unloading components | |||||

Time consumption for an unloading stop (PMmin) | 0.016 | 0.917 | 0.878 | 5.0 | 52 |

Time consumption for an unloading crane cycle (PMmin) | <0.001 | 0.767 | 0.470 | 15.1 | 200 |

Number of unloading stops per load | <0.001 | 0.344 | 0.344 | 94.8 | 18 |

Number of unloading crane cycles per load | <0.001 | 0.926 | 0.168 | 85.3 | 18 |

Number of unloading crane cycles per stop | <0.001 | 0.659 | 0.735 | 71.6 | 52 |

Significant values (p < 0.05) in bold. |

Table 4. Time consumption (mean and standard deviation (SD), PMmin (m^{3}ob)^{–1}) for work elements by total log concentration and the number of assortments in a load. | |||||||||

Work element | Total log concentration (m^{3}ob (100 m)^{–1}) | Number of assortments in a load | |||||||

Balanced two-way ANOVA | Supplements for one-way ANOVA | ||||||||

1 | 3 | 2 | 5 | ||||||

Mean | SD | Mean | SD | Mean | SD | Mean | SD | ||

Work elements pooled | 6.4 | 3.19^{A,a} | 0.17 | 2.90^{A,b} | 0.02 | 3.60^{c} | 0.09 | ||

19.2 | 1.97^{BC,a} | 0.06 | 2.38^{B,a} | 0.33 | 1.95^{a} | 0.13 | |||

32.0 | 1.69^{C} | 0.11 | 2.39^{B} | 0.16 | |||||

Loading | No effect | 0.94^{a} | 0.08 | 1.13^{b} | 0.06 | 1.04^{ab} | 0.01 | 1.40^{c} | 0.10 |

Driving while loading | 6.4 | 1.86^{A,a} | 0.05 | 0.72^{B,b} | 0.02 | 0.46^{c} | 0.03 | ||

19.2 | 0.72^{B,a} | 0.01 | 0.26^{D,b} | 0.02 | 0.36^{c} | 0.01 | |||

32.0 | 0.41^{C} | 0.03 | 0.13^{E} | 0.01 | |||||

Unloading | No effect | 0.34^{a} | 0.03 | 0.89^{b} | 0.17 | 0.47^{a} | 0.07 | 1.43^{c} | 0.20 |

Driving while unloading | No effect | 0^{a} | 0 | 0.16^{b} | 0.04 | 0.07^{ab} | 0.05 | 0.31^{c} | 0.11 |

Different superscript uppercase letters within work elements pooled and driving while loading indicate significant differences (p < 0.05) between the six combinations of total log concentration and 1 and 3 assortments (Two-way ANOVA with Tukey test). When there was no effect from total log concentration (see Table 3), data within 1 and 3 assortments were pooled (i.e. means based on 9 loads instead of 3). Different superscript lowercase letters within rows indicate significant differences (p < 0.05) (One-way ANOVA with Tukey test). |

Table 5. Observations (mean and SD) for loading components by total log concentration and the number of assortments in a load. View in new window/tab. |

Table 6. Comparisons at equal forwarded log concentrations: the main effect of number of assortments in a load α and the covariate forwarded log concentration on the strip-road γ (m^{3}ob (100 m)^{–1}). View in new window/tab. |

Table 7. Observations (mean and SD) for unloading components by the number of assortments in a load. View in new window/tab. |