## 3 Results
The other characteristics determined were as follows:  
- the participation of class \(i\) in the sample; \(p_{i}=(n_{i}/T_{s})\times 100\);  
- average \(i\) class size; \(c_{i}=c_{min}+\lambda(2i-1)/2\);  
- the distribution curve of the seeds \(y\)  
Analyzing the specific distribution curves, we observed that the hybrid whose specific distribution curve by thicknesses was closest to the normal distribution curve was SUM 96521. The graphs in Figures 9-11 help to determine the participation of fractions in the mass of hybrids, namely,  
- seed size fractions \(c\in[M_{c}-\sigma_{c},M_{c}+\sigma_{c}]\);  
- seed size fractions \(c\in[M_{c}-2\sigma_{c},M_{c}+2\sigma_{c}]\);  
- seed size fractions \(c\in[M_{c}-3\sigma_{c},M_{c}+3\sigma_{c}]\). The values obtained are shown in Table 10.  
Using the data in Table 3 for coordinates \(X_{p}\) and \(Y_{p}\), the diagram for the contact point of seeds with the cylindrical sieve was obtained, as shown in Figure 12.  
Figure 11: The specific distribution curve by thickness for the Kalista hybrid. Figure 12: Contact points between the seed and the cylindrical sieve. The diagram obtained in \(X_{p}\) and \(Y_{p}\) coordinates represents an arc of a circle inscribed in quadrant 4. From Figure 12 and analyzing the data in Table 3, it can be observed that as the angle \(\theta\) took values between 50 and 60 degrees, \(X_{p}\) and \(Y_{p}\) decreased, with the contact point approaching the inferior point of the cylindrical sieve, the point of relative repose, with these points being the best points for the seeds to pass through the orifices of the cylindrical sieve. Figure 13 shows the influence of the revolution speed on the calibration of corn seeds on the sieve with 5 mm \(\times\) 25 mm orifices. From Figure 14, it can be seen that the number of separated seeds was the highest for the smallest revolution speed (33 rot/min) and decreased when increasing the revolution speed up to 49 rot/min; the only exception was observed for the LG2244 hybrid, with this being explained by the distribution curve for this hybrid where it can be seen that the number of these seeds was equal for various classes of sizes. Also from Figure 14, it can be observed that when the revolution speed was higher than 40 rot/min, the decrease in seed separation was lower. The speed of the cylindrical sieve with constant speed can be increased (therefore in terms of its productivity) without the appearance of relative rest, by using special devices: internal cylindrical screens, internal inclined planes, internal cylindrical screens with brushes, etc. Using such solutions, the speed can be increased 2-3 times compared to the speed of the simple cylindrical sieve, increasing its productivity accordingly. During operation, the seed mixture is not distributed uniformly over its entire inner surface, but in a layer of uneven thickness having in the cross-section approximately the shape of a biconvex lens, which extends over an angle to the center of about 90-100\({}^{\circ}\), so the contact of the seeds with the sieve is made on a small surface of it (about \(\frac{1}{4}\)). The working surface can be increased by using the same devices presented above. Figures 14 and 15 show the influence of sieve length on the calibration process for the lowest and highest revolution speeds. From Figures 14 and 15, it can be seen that for both revolution speeds, the highest part of separated seeds was found on the first third of the cylindrical sieve length. In the remaining two thirds, with small fluctuations, the separation was uniform. Measurements showed that in the first third of the sieve's length, the seeds were separated that had a thickness up to 4.8 mm, and in the other two thirds of the sieve's length, the seeds with thicknesses between 4.8 and 5 mm were separated. Figure 13: Influence of revolution speed on the calibration of corn seeds on the 5 mm \(\times\) 25 mm sieve.