## 4 Experimental Program
### First Series
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline
**Cores** & **D** & \(R_{cd}\) & \(R^{md}{}_{c,a}\) & **D** & \(R_{ep}\) & **C\({}_{\rm EV}\)** & \(R^{md}{}_{c,e}\) & **ESC** \\ \hline CVD a & 2.50 & 30.75 & & 3.25 & 39.98 & & & \\ CVD b & 2.50 & 34.75 & & 3.25 & 45.17 & & & \\ CVD c & 2.50 & 34.26 & & 3.25 & 44.53 & & & \\ CVD d & 2.50 & 38.51 & & 3.25 & 50.07 & & & \\ CVD e & 2.50 & 38.50 & 35.35 & 3.25 & 50.05 & 1.04 & 47.80 & C35/45 \\ \hline CMD a & 2.50 & 23.45 & & 3.25 & 30.48 & & & \\ CMD b & 2.50 & 24.07 & & 3.25 & 31.29 & & & \\ CMD c & 2.50 & 30.21 & & 3.25 & 39.28 & & & \\ CMD d & 2.50 & 31.57 & 29.56 & 3.25 & 41.04 & 1.13 & 40.14 & C32/40 \\ \hline MSC i a & 2.30 & 30.83 & & 3.00 & 39.83 & & & \\ MSC i b & 2.30 & 35.69 & & 3.00 & 46.56 & & & \\ MSC i c & 2.30 & 41.82 & & 3.00 & 54.55 & & & \\ MSC i d & 2.30 & 44.25 & 36.77 & 3.00 & 57.72 & 1.00 & 49.66 & C35/45 \\ \hline MDC i a & 2.30 & 39.02 & & 3.00 & 50.90 & & & \\ MDC i b & 2.30 & _37.62_ & & 3.00 & 49.07 & & & \\ MDC i c & 2.30 & 33.21 & & 3.00 & 43.32 & & & \\ MDC i d & 2.30 & 42.47 & & 3.00 & 55.40 & & & \\ MDC i e & 2.30 & 36.08 & 37.68 & 3.00 & 47.06 & 1.00 & 49.15 & C35/45 \\ \hline ARC2 a & 2.30 & 25.81 & & 3.00 & 33.66 & & & \\ ARC2 b & 2.30 & 22.57 & & 3.00 & 29.44 & & & \\ ARC2 c & 2.30 & 32.48 & & 3.00 & 42.36 & & & \\ ARC2 d & 2.30 & 26.00 & & 3.00 & 33.91 & & & \\ ARC2 e & 2.30 & 35.07 & & 3.00 & 45.74 & & & \\ ARC2 f & 2.30 & 24.83 & 28.19 & 3.00 & 32.39 & 1.04 & 37.70 & C30/37 \\ \hline ARC3 a & 2.30 & 25.54 & & 3.00 & 33.31 & & & \\ ARC3 b & 2.30 & 27.52 & & 3.00 & 35.90 & & & \\ ARC3 c & 2.30 & 26.14 & & 3.00 & 34.10 & & \\ ARC3 d & 2.30 & 28.44 & 26.50 & 3.00 & 37.10 & 1.04 & 36.51 & C25/30 \\ \hline \end{tabular}
\begin{tabular}{c c c c c c c c} \hline  & & & & & & & \\ D = parameter depending on the direction of perforation; \(R_{c,a}\) = estimated actual strength; \(R^{md}{}_{c,a}\) = mean value; \(R_{ep}\) = estimated potential strength; \(R^{md}{}_{c,p}\) = mean value; \(\rm{CE}\) = corrective factor; \(\rm{ESC}\) = estimated strength class; \(\rm{S}\) \\ \hline \end{tabular}
\end{table} 
Table 4: Third group—estimated strength class (ESC) by CSTR procedure. \begin{table}
\begin{tabular}{c c c c c c c c} \hline
**Cores** & **D** & \(R_{c,a}\) & \(R^{md}{}_{c,a}\) & **D** & \(R_{ep}\) & **C\({}_{\rm EV}\)** & \(R^{md}{}_{c,p}\) & **ESC** \\ \hline MSC i a & 2.30 & 25.19 & & 3.00 & 32.86 & & & \\ MSC i b & 2.30 & 28.82 & & 3.00 & 37.59 & & & \\ MSC i c & 2.30 & 29.10 & & 3.00 & 37.96 & & & \\ MSC i d & 2.30 & 31.14 & & 3.00 & 40.62 & & & \\ MSC i e & 2.30 & 30.37 & & 3.00 & 39.61 & & & \\ MSC i f & 2.30 & 33.39 & & 3.00 & 43.55 & & & \\ MSC i g & 2.30 & 35.99 & 30.57 & 3.00 & 46.94 & 1.00 & 39.88 & C30/37 \\ \hline MSC 2 a & 2.30 & 30.89 & & 3.00 & 40.30 & & & \\ MSC 2 b & 2.30 & 29.33 & & 3.00 & 38.26 & & & \\ MSC 2 c & 2.30 & 34.62 & & 3.00 & 45.16 & & & \\ MSC 2 d & 2.30 & 34.17 & 32.25 & 3.00 & 44.57 & 1.04 & 43.75 & C32/40 \\ \hline ARC1 a & 2.30 & 29.24 & & 3.00 & 38.14 & & & \\ ARC 1 b & 2.30 & 26.71 & & 3.00 & 34.83 & & & \\ ARC 1 c & 2.30 & 25.94 & & 3.00 & 33.83 & & & \\ ARC 1 d & 2.30 & 29.05 & & 3.00 & 37.89 & & & \\ ARC 1 e & 2.30 & 30.09 & & 3.00 & 39.25 & & & \\ ARC 1 f & 2.30 & 33.61 & 29.11 & 3.00 & 43.84 & 1.04 & 39.48 & C30/37 \\ \hline CVD a & 2.50 & 30.75 & & 3.25 & 39.98 & & & \\ CVD b & 2.50 & 29.88 & & 3.25 & 38.85 & & & \\ CVD c & 2.50 & 31.73 & & 3.25 & 41.25 & & & \\ CVD v & 2.50 & 32.53 & 31.22 & 3.25 & 42.30 & 1.04 & 42.22 & C32/40 \\ \hline \end{tabular}
\begin{tabular}{c c c c c c c c c} \hline  & & & & & & & & \\ D = parameter depending on the direction of perforation; \(R_{c,a}\) = estimated actual strength; \(R^{md}{}_{c,a}\) = mean value; \(R_{ep}\) = estimated potential strength; \(R^{md}{}_{c,p}\) = mean value; \(\rm{CE}\) = corrective factor. & \(\rm{ESC}\) = estimated strength class; \(\rm{S}\) \\ \hline \end{tabular}
\end{table} 
Table 3: Second group—Estimated Class by CSTR procedure.