| Popis: |
The quantification of the solid wood content in a wood stack is an object of investigation since the 18th century. Especially the log parameters exert a considerable influence on the volume of the stack. Some important parameters which were analyzed by this method are (1) log midpoint diameter, (2) average bark thickness, (3) crookedness and (4) log taper. Although many of these parameters have already been studied and some are already considered in many countries when measuring wood stacks, their influence has not been analyzed individually so far since a broad statistical database is needed and the data collection is very costly. Consequently 3D-simulation model was developed based on a cross-platform game engine. This model generates virtual wood stacks based on a data set of logs which are defined by the user. One simulation cycle needs a few seconds and each stack generated can be visualized once all iterations are done. The simulation results are the stacked cubic volume, solid wood cubic volume and the respective conversion factors. The model, fed with both real collected and user-defined data, allows a detailed analysis of the effect of each parameter on the results, as the user can vary their values discretionary as well. To obtain the first results from real data, 400 logs of Norway spruce were measured. The first simulations based on these data showed reliable results and it was possible to quantify the influence of the parameters described above on stack volume. In addition, the results are highly in line with the real trials that have already been done in parallel around the world. Although a further scientific evaluation and statistical analysis will be done in a second study phase, the model provides a reasonable tool that is easy to apply for the forest and wood industry in order to make the most accurate estimate possible of the solid wood content. |
