## 4 Discussion  
This study can be compared only partially with previous literature [1; 22; 28; 33]. The reason for this is that those studies used cutouts for ventilation purposes in standard locations and sizes generally used in practice. Based on this, the role of the sidewall cutouts in influencing the strength cannot be determined. Study of [PERSON] et al. [32] would be a point of reference partly due to the same FEFCO 0201 box type samples, but it did not observe the effect of the length-to-width ratio and the cutout size together. That study used only a 1.5 (300 \(\times\) 200 mm) length-to-width ratio. In our study, starting from the geometric center of the box sidewalls, the cutout area of the sidewall was continuously increased in cases with the same manufacture and design, so that a clear observation between the sidewall cutout area and associated maximum compression strength can be obtained. In ref. [34], where the effect of the aspect ratio on box compression strength was investigated, the authors showed that the compressive strength increases at first and then decreases, and the maximum compression strength appeared when the length-to-width ratio was about 1.6. The results of this study have shown a good correlation with [33], but in our case, the optimal length-to-width ratio was 1.33. It should be noted here that in [33], the material of the tested corrugated box was a BC flute corrugated cardboard with five layers, but in our tests, a B flute corrugated cardboard with a single wall design was applied. So, it can be presumed that the different optimal length-to-width ratio in our case came from the different corrugated box material. Based on our study, a corrugated box with a 1.33 length-to-width ratio made from B flute corrugated cardboard with three layers showed the best result; therefore, it can be assumed that this is the most suitable ratio for logistics usage if other conditions are met. Here, it has to be mentioned that the scientific literature examines many variables compared to our study, such as the quality of the corrugated cardboard, the number of layers, the shape and position of the cutouts or ventilation holes, temperature and/or humidity changes and box height. Our study reduced the number of variables to two in order to be able to clearly examine the effect of the length-to-width ratio (by keeping the height constant) and cutout sizes. The shape of the cutouts was perfectly square, and these are placed precisely in the center of the sidewalls. No such study has presented this before. Of course, these cutouts reduced the sidewall surface area; thereby, it logically changed the mechanical behavior of the box structure. Further research is needed to determine the correlation between the reduction in compression strength and different cutout sizes involving more cardboard types and quality. However, the results of this study can give better guidance on the placement of the handle and ventilation holes, taking into account the factor of the box length-to-width ratio. It can be assumed that the average of maximum compression force decreases when the cutout rate increases. The 400 \(\times\) 300 \(\times\) 300 sized box was strongest in each group. So, in this study, the results showed that the optimal box size with or without cutouts has a 1.33 length-to-width ratio. The statistical tests showed that there is no significant difference between the 0% and 20% cutout groups, so the compression strength of the boxes was not changed significantly if a 20% cutout was used. The preliminary results presented in this study make a reasonable first approximation of interconnection within the base length-to-width ratio and cutout sizes of the boxes. The authors would like to draw the attention to additional ongoing research involving more variables that focus on such variables as cardboard quality with different layer numbers, flute heights and grammage per square meter.