A feasibility study of low-power laser trepanning drilling of composite using modified DVD writer

In the present study, laser cutting of cotton fiber composite laminate is experimented using a modified DVD writer drive. A 250 mW diode laser is initially extracted from a DVD writer drive, and then regulated by a custom-made laser driver circuit designed using a Proteus® software. Experimental tests are carried out using multi-pass laser trepanning drilling at different drilling speeds and standoff distances (SODs). The cut quality is evaluated by measuring the extent of both oxide and resolidified resin regions. It was discovered high speed of trepanning drilling and positive SOD significantly improve cutting region quality. Furthermore, positive and negative SODs require relatively high number of passes at different drilling speeds. From SEM micrographs, it is found out that the crack formation and fiber protruding happen in thedrilling area due to thermal stresses and matrix vaporization

Edupreneurship management in shaping the nation's character

The character cannot be directly obtained,it is instantaneous but requires time with the custom of academic habits to become a necessity and ultimately to get entrepreneurial skills, the purpose of identifying students' entrepreneurial skills in supporting the nation's character. Mix method with Convergence Model and t-test analysis shows that there are differences in indicators of student entrepreneurial skills with character education treatment and those that are not. There is the lowest indicator on creative thinking and responding to global problems by 60% enough categories. so it needs to be improved in further research with edupreneurship designs that are characterized in preparation, teaching materials, resources and learning media that are adapted to technological developments. Keyword: Edupreneurship Nation's characte