A full factorial design of experiments was used to study the effect of blend shear strain on the compaction process, relative density and strength of pharmaceutical tablets. The powder blends were subjected to different shear strain levels (integral of shear rate with respect to time) using an ad hoc Couette shear cell. Tablets were compressed at different compaction forces using an instrumented compactor simulator, and compaction curves showing the force-displacement profiles during compaction were obtained. Although the die-fill blend porosity (initial porosity) and the minimum in-die tablet porosity (at maximum compaction) decreased significantly with shear strain, the final tablet porosity was surprisingly independent of shear strain. The increase in the in-die maximum compaction with shear strain was, in fact, compensated during postcompaction relaxation of the tables, which also increased significantly with shear strain. Therefore, tablet porosity alone was not sufficient to predict tablet tensile strength. A decrease in the 'work of compaction' as a function of shear strain, and an increase in the recovered elastic work was observed, which suggested weaker particle-particle bonding as the shear strain increased. For each shear strain level, the Ryskewitch Duckworth equation was a good fit to the tensile strength as a function of tablet porosity, and the obtained asymptotic tensile strength at zero porosity exhibited a 60% reduction as a function of shear strain. This was consistent with a reduced bonding efficiency as the shear strain increased.

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Objectives This study aimed to analyze the effects of self-directed learning ability, self-regulatory efficacy, collaboration preference, and communication skill according to college students’ participation in learning community activities in order to find an effective management plan for the learning community. Methods To do so, a survey was conducted on 422 students at S College in Gyeonggi-do. The experimental group had 181 students who participated in the learning community program run by the Center for Teaching and Learning Development in the first semester of 2022. The control group consisted of 241 people who did not participate in the learning community program. To verify the effect of learning community participation, pre- and post-surveys were carried out at the beginning and end of the learning community activities of the experimental group and For statistical verification, covariance analysis(ANCOVA) was performed. Results The analysis results showed that the self-directed learning ability, self-regulatory efficacy, collaboration preference, and the communication skill of college students who participated in the learning community improved. Conclusions This study is meaningful in that it analyzed the effect of the learning community program on college students and provided basic data for the measures to vitalize learning communities in colleges and performance analysis.