Figures 2(a) and 2(b) show the results for a batch distillation column operating at constant reflux ratio of 2.0 with ten theoretical stages. In Figure 2(a) it is observed that at the bottom of the column, the composition of benzene decreased with time while the composition of the heavy components increased.arolo and Guarice [ 8 ] extended their continuous short-cut method to batch distillation columns and used an infinite stage column. Seader and Henley [ 9, 10 ] applied Sundaram and Evans [ 3 ] method and showed how the FUG equations were used to solve a simulation problem with constant reflux.
Executive Summary on Persistence and Retention Topics. â¢ Retention rates commonly measure the percentage of freshmen that re-enroll the next academic year as sophomores. The primary reason that retention rates, along with graduation rates, are important is that retention rates are. perceived as indicators of academic quality and student success. â¢ In addition to retention, persistence, a studentâs continuation behavior leading to a desired goal, helps describe.
Grade retention or grade repetition is the process of having a student repeat an educational course, usually one previously failed. Students who repeat a course are referred as repeaters. Repeaters can be referred to as having been held back.The primary alternative to grade retention (for those who have failed) is a policy of social promotion, under the ideological principle that staying with their same-age peers is important.Social promotion is the promotion of all students, regardless of achievement, from one class to the next.ost schools refuse to retain a student more than once in a single grade, or more than two or three years across all grades. Students with intellectual disabilities are only retained when parents and school officials agree to do so.