摘要：Anterior cruciate ligament （ACL） injuries are common in soccer. Understanding ACL loading mechanisms and risk factors for ACL injury is critical for designing effective prevention programs. The purpose of this review is to summarize the relevant literature on ACL loading mechanisms, ACL injury risk factors, and current ACL injury prevention programs for soccer players. Literature has shown that tibial anterior translation due to shear force at the proximal end of tibia is the primary ACL loading mechanism. No evidence has been found showing that knee valgus moment is the primary ACL loading mechanism. ACL loading mechanisms are largely ignored in previous studies on risk factors for ACL injury. Identified risk factors have little connections to ACL loading mechanisms. The results of studies on ACL injury prevention programs for soccer players are inconsistent. Current ACL injury prevention programs for soccer players are clinically ineffective due to low compliance. Future studies are urgently needed to identify risk factors for ACL injury in soccer that are connected to ACL loading mechanisms and have cause-and-effect relationships with injury rate, and to develop new prevention programs to improve compliance.

摘要：强化函数的设计是构建多智能体学习系统的一个难点。提出了一种基于知识的强化函数设计方法,根据实际应用的特点,将经验信息和先验知识引入到强化函数中,提高了强化学习的性能。通过在Robotsoccer中的应用和实验,基于知识的强化函数的学习效果要优于传统的强化函数。

摘要：听说课是初中英语的一种基本课型,但由于初中英语教学内容多,教学课时少等原因,听说教学的重要地位并没有得到充分体现,很多时候都是老师播放听力录音,学生做题目。这种课堂教学模式,导致学生不喜欢开口说,同时也缺乏听的兴趣。《义务教育英语课程标准(2011年版)》对初中毕业生的语言技能要求是五级,其中'听'的标准描述涉及六项,'说'的标准描述涉及七项。基于对课程要求的分析,笔者以学生为中心,创设真实的情境,通过五个环节开展Section A(1a-1c)的听说课:明标引课、自学探究、精讲点拨、训练达标和小结提升。

摘要：一、教学任务分析