For the smooth transition from paper-based procedures used in operations and maintenance to tablet-based procedures, we produced six types of tablet-based procedures that implemented several required functions proposed by users. In this study, Operational experiments had conducted on the functional aspects of six different tablet-based procedures as opposed to the usability of paper-based procedures. As a result, we confirmed five practical effects, including functions such as the following (1) It is easy to use if all procedures displayed on the tablet are loaded together and displayed by sending pages one by one as if they were paper. (2) Materials related to operations should be easy to use by creating and saving folders for each type and displaying them when needed.

We aim to construct a method to apply Formal Concept Analysis to small-scale data and to use the logic of implication obtained from the analysis for statistical analysis. Specifically, we obtain learning history data of e-learning system users in a class of about 40-60 students in a given year, and use Formal Concept Analysis to obtain an implication relation that can be expressed as “a person who answers one question (group) correctly or incorrectly will always answer another question (group) correctly or incorrectly”. We compare the tendency of correct/incorrect answers of the questions (groups) included in the obtained implication relation with the relationships among the questions (groups) obtained from the statistical analysis of the data of multiple years, which is larger than the group to which Formal Concept Analysis was applied.

This paper proposes a controller design methodology for an encrypted control system that prevents data leakage. In previous model-based design studies, there was a risk of information leakage during the design process. Therefore, this study proposes a method to design a controller directly from the encrypted data. By using the proposed method, security can be maintained both during control system design and during control.