系统思考与现代管理——以阿姆布雷斯岛旅游业发展为例分析

系统思考作为现代管理中的重要方法和手段,正在受到越来越多人的重视和推崇。它强调整体性和动态性复杂,处理和对待事物是必须考虑时间滞延效应。运用系统思考基模分析和处理旅游业发展带来的种种问题,才能使旅游业健康持续稳定地增长。

Research on temperature rise of hoisting machine disk brake

A mathematical model and finite element model for analysis of temperature rise of the hoisting machine brake sys- tem was constructed, limit conditions were defined, and the law of temperature rise of brake shoes during emergent brake course was analyzed and calculated by using finite element software. By analyzing the calculation results, the law of tempera- ture change of surface of brake disk and shoes during the braking process was found. The law of brake shoes surface tempera- ture distribution and the law of temperature change along with thickness of brake shoes at brake time 0.5 s, 1.0 s and 1.5 s was analyzed. A hoisting machine emergent braking test was carried out. Finally, the author concluded that velocity rebound in the process of hoisting machine emergent brake is due to decreased friction coefficient caused by the temperature rise of the brake shoes surface.

有关疑问域的一点历时思考

古代、近代汉语中不存在疑问域限制规律,"邪(耶)"、"与"、"乎"等疑问语气词可出现于各类问句。现代汉语"吗"与"呢"的互补分布也是在历时演变中自然形成的。"吗"的使用能造成疑问域的移动,这可以用疑问域限制规律来解释,更可以从"吗"(及其前身"不"、"无")的历时演变中找到答案。非疑问语气词"吧"的使用有时也会造成疑问域的移动。