Application of the Ultimate Hanging Arch Length of the Layered Roof with Anchors and the Gob-Side Entry Retaining

The gob-side entry retaining plays an important role in improving working face ventilation, alleviating working face connection, and increasing mining revenue. According to the characteristics of the crossheading roof at the 2103 working face of a mine in Shanxi, a structural mechanics model of the roof was established to derive the theoretical formulae for the ultimate hanging arch length of the layered roof with anchors and the initial support resistance of the entry-side support. The influence factors of the ultimate hanging arch length were evaluated using local sensitivity analysis. Based on the theoretical study, the work proposed the collaborative support technology of the crossheading, collaborative support at the 2103 working face. The results showed that the ultimate hanging arch length was most influenced by the width of the plastic zone, followed by the width of the roadway, supporting strength, anchoring strength, layered thickness, and mining depth, while the ultimate tensile strength had little influence. The initial support resistance of the entry-side supports was closely related to the ultimate hanging arch length and the process of gob-side entry retaining. The improved entry-retaining supporting process could control the sharp surface convergence of the surrounding rocks of the entry retaining, the sinkage of the roof of the entry-retaining section was controlled below 100 mm, and that of the advanced section was controlled below 50 mm. The stability of the supports next to the entry is improved, and the needs of the site project are met.

Benefits of and Challenges to Becoming a Teacherpreneur

This chapter educates the reader on the benefits of and challenges to becoming a teacherpreneur. The benefits—which include being able to set their own work schedule, having control over what additional responsibilities they take on, supplemental income, or becoming a better teacher due to the reflective practices—typically outweigh the challenges, which can include working alone, lack of a steady income (especially in the beginning when starting out), excessive paperwork to fill out (e.g., self-employment taxes, paperwork to consult with a school), lack of collaborative support, an unpredictable work schedule, and a high level of competition. Educators who are interested in becoming teacherpreneurs should be aware of the benefits and challenges discussed herein prior to getting involved in this educational movement.

A Collaborative Support for Recommending References in Papers

Understanding citations to scientific publications is a task of vital importance in the academic world. This task can be supported by appropriate data structures and visualization mechanisms. One challenge is the amount of existing relationships and the difficulty of determining which of the references of a document are considered the most potentially relevant to it. In this paper, we propose a visual approach based on graphs to recommend important references. Also, we propose a procedure to build and update the citation graph in a collaborative way.