=Injection molding is now used to mold plastic parts with precision contours such as lenses. Cooling conditions have critical effects on the quality and productivity of such precision parts. This article is devoted to investigate the effects of mold temperature and cooling time on quality. A two-cavity mold for molding convex lenses with square-looped cooling channels was used. Samples molded with different mold temperatures and cooling times were collected, and their contour conformity to those of the cavity was evaluated. Contour errors were defined. The correlation between mold temperature and cooling time and contour errors was analyzed. It has been found that for a given mold temperature, two critical cooling times can be defined at which the thermal and rigidity states pass through a transition. Most dramatic improvements in part conformity occur around such critical points. 0 1996

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Improving the scientific research productivity of lecturers is an important strategy contributing to improving the reputation of universities, attracting external funding sources, and improving the credibility of both domestic and international students. This study was carried out with the aim of determining the priority of the university’s governance factors that affect lecturers’ scientific research productivity. Six university governance factors were considered, including (i) research objectives and strategies, (ii) decentralization, (iii) leadership, (iv) support for research activities, (v) policy towards lecturers, and (vi) resources for research activities. In this study, an improved analytic hierarchy process method using generalized triangular fuzzy numbers and a centroid index was proposed. The research data were collected via in-depth interviews with experts and administrators at Vietnam National University, Hanoi (VNU). The results indicate that “resources for research activities” constitute the most important factor affecting the research productivity of lecturers at VNU, followed by research objectives and strategies and leadership.

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