## 1 Introduction
cylinder, which causes the former to gain strength faster than the latter. Predictive analysis on large datasets and the multiple variables and their variances requires a reduction in the complexity and noise of the data so that the critical features \begin{table}
\begin{tabular}{c c} \hline \hline
**Method** & **Description** \\ \hline Method \#C1 & \begin{tabular}{c} Cured in ambient air in direct sunlight in an outdoor concrete site and stripped on the day of the test. Cylinders are covered with a curing blanket (e.g., 2.5 cm (1/2 in.) thick with an R-value = 5.7) during extremely cold weather. \\ \end{tabular} \\ \hline Method \#C2 & \begin{tabular}{c} Gang-cured (e.g., 10 cylinders in a box) in an insulated box (e.g., a cooler) in direct sunlight in an outdoor concrete site and stripped on the day of the test. For example, a cooler rated as a “5-day cooler” can keep ice for up to 5 days in temperatures as high as 32 \({}^{\circ}\)C (90 \({}^{\circ}\)F). \\ \end{tabular} \\ \hline Method \#C3 & \begin{tabular}{c} Gang-cured (e.g., 10 cylinders in a box) in a thermostatically controlled curing box (or power-operated) in direct sunlight in an outdoor concrete site and stripped on the day of the test. The power is kept on for 24 h at 21 \({}^{\circ}\)C (70 \({}^{\circ}\)F) after the casting of cylinders and then turned off. \\ \end{tabular} \\ \hline Method \#B1 & \begin{tabular}{c} Cured in ambient air in direct sunlight in an outdoor concrete site. In cold weather, the beams are covered with a curing blanket (e.g., 2.5 cm (1/2 in.) thick with an R-value = 5.7). \\ \end{tabular} \\ \hline Method \#B2 & \begin{tabular}{c} Gang-cured in a beam box in direct sunlight in an outdoor concrete. Beam boxes can be manufactured using a foam board (R-value = 10) sandwiched in two plywood sheets to provide insulation to beams (total R-value = 12). Two beams were placed inside each box. \\ \end{tabular} \\ \hline Method CIP & \
\begin{tabular}{c} Core-drill or cure cylinders inside a concrete item. \\ \end{tabular} \\ \hline Other &
\begin{tabular}{c} Cylindrical specimens are field cured under burlap/insulation, while beams are cured in a damp sandpit or under burlap/insulation. Other field-curing technologies include match curing, SureCureTM cylinder-mold system, piezoelectric sensors, calorimetry, and penetration-resistance tests. \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Common concrete curing methods. and relationships can be identified. Table 2 discusses several techniques for reducing dataset dimensionality. Principal component analysis (PCA) was used to identify, analyze, and visualize summary indexes for multiple independent variables (e.g., [10; 11]). As a statistical technique for the assessment of the differences in means among multiple groups, analysis of variance (ANOVA) partitions the variance into between-group and within-group components before testing whether the means of several groups are equal. With a focus on multivariate, MANOVA disregards the statistical significance of variances and produces differences among levels of independent variables. Therefore, MANOVA applies to multiple dependent variables and is an inferential statistical analysis. The selection of concrete curing methods should consider mix designs, moisture rates, variations in specimen shapes and sizes (e.g., 4 in. cylinders, 6 in. cylinders, or 20 in. beams in the dimensions of 150 by 150 mm with a minimum length of 530 mm), temperatures, curing durations, and material strength development [15]. However, some of the multiple influence factors (a.k.a., independent variables) affect each other, which increases the complexity of the method selection [7]. For example, industry professionals noticed that beam specimens seem to take less time for strength development than smaller 100 mm \(\times\) 200 mm (4 in. \(\times\) 8 in.) cylindrical specimens [9]. Hence, contractors and site engineers prefer to use beams to test concrete strength because they can load structures or open the pavement to traffic sooner.