For the underwater long baseline(LBL)positioning systems,the traditional distance intersection algorithm simplifies the sound speed to a constant,and calculates the underwa-ter target position parameters with a nonlin...For the underwater long baseline(LBL)positioning systems,the traditional distance intersection algorithm simplifies the sound speed to a constant,and calculates the underwa-ter target position parameters with a nonlinear iteration.However,due to the complex underwater environment,the sound speed changes with time and space,and then the acoustic propagation path is actually a curve,which inevitably causes some errors to the traditional distance intersection positioning algorithm.To reduce the position error caused by the uncertain underwater sound speed,a new time of arrival(TOA)intersection underwater positioning algorithm of LBL system is proposed.Firstly,combined with the vertical layered model of the underwater sound speed,an implicit positioning model of TOA intersection is constructed through the constant gradient acoustic ray tracing.And then an optimization function based on the overall TOA residual square sum is advanced to solve the position parameters for the underwater target.Moreover,the particle swarm optimization(PSO)algorithm is replaced with the tra-ditional nonlinear least square method to optimize the implicit positioning model of TOA intersection.Compared with the traditional distance intersection positioning model,the TOA intersec-tion positioning model is more suitable for the engineering practice and the optimization algorithm is more effective.Simulation results show that the proposed methods in this paper can effectively improve the positioning accuracy for the underwater target.展开更多
目的本研究旨在探讨BOPPPS联合案例为基础的学习方法(case-based learning,CBL)+教师主导式教学(lecture based learning,LBL)教学模式在心脏查体带教中的应用效果。方法以广东医科大学2020级本科临床医学专业的132名学生为研究对象,采...目的本研究旨在探讨BOPPPS联合案例为基础的学习方法(case-based learning,CBL)+教师主导式教学(lecture based learning,LBL)教学模式在心脏查体带教中的应用效果。方法以广东医科大学2020级本科临床医学专业的132名学生为研究对象,采用随机数字表法分为对照组(65人)和试验组(67人)。试验组男37人,女30人,年龄(22.37±0.91)岁;对照组男35人,女30人,年龄(22.68±0.69)岁。试验组采用BOPPPS联合CBL+LBL教学模式进行教学,而对照组采用传统的CBL+LBL教学法。最后采用问卷形式对教学效果进行评价。采用χ^(2)检验、独立样本t检验。结果试验组学生的满意度高于对照组[98.5%(66/67)比86.2%(56/65)],差异有统计学意义(P<0.05)。自我评价方面,在“是否激发学习兴趣、是否提高对学习重点难点的掌握、是否增强临床操作技能培养、教学组织的合理性及是否提高临床学习的兴趣”5个项目方面,试验组的学生评价均优于对照组(均P<0.05);在“培养临床思维能力、增强解决问题的能力、师生及医患的沟通和表达能力、学习效率及能力的提高、团队合作能力”5个项目方面,两组之间差异均无统计学意义(均P>0.05)。结论与传统CBL+LBL教学法相比,BOPPPS联合CBL+LBL教学模式,不仅可以提高学生的学习效率,激发其学习兴趣、积极性,同时也增强了他们的临床思维和临床操作技能。因此,这种教学模式具有很好的教学效果,值得推广和应用。展开更多
目的 探究讲授式教学法(lecture based learning,LBL)、以问题为基础的教学方法(problem-based learning,PBL)、慕课(massive open online course,MOOC)联合翻转课堂对于临床医学专业留学生临床实习效果的影响。方法选取2018年6月-2019...目的 探究讲授式教学法(lecture based learning,LBL)、以问题为基础的教学方法(problem-based learning,PBL)、慕课(massive open online course,MOOC)联合翻转课堂对于临床医学专业留学生临床实习效果的影响。方法选取2018年6月-2019年6月在哈尔滨医科大学附属第一医院6年制临床医学毕业实习阶段留学生共80名作为研究对象,随机分成4组,每组20人,分别采用4种不同教学模式进行神经内科实习教学:1组采用LBL教学法;2组采用PBL教学法;3组采用LBL联合PBL教学法;4组采用LBL+PBL+慕课联合翻转课堂。课后向每名同学发放调查问卷以此了解学生的满意情况,实习结束以后对4组学生进行理论和临床技能综合考试。以评估留学生的临床知识掌握能力、临床技能操作能力、临床病例分析能力。结果 第4组学生临床知识掌握能力、临床技能操作能力、临床病例分析能力均高于其他3组留学生,差异有统计学意义(P <0.05);第4组学生在专业知识涵盖满意度、临床思维培养满意度、教学体验满意度3个方面评分高于其他3组学生,差异有统计学意义(P <0.05)。结论 在留学生临床实习教学中采用LBL+PBL+MOOC联合翻转课堂教学模式效果显著,能有效激发学生的主观能动性,培养学生自主学习和分析问题的能力,提高学生的学习成绩及临床知识掌握能力、临床技能操作能力、临床病例分析能力,提升整体教学效果和教学满意率。展开更多
基金supported by the National Natural Science Foundation of China(61903086,61903366,62001115)the Natural Science Foundation of Hunan Province(2019JJ50745,2020JJ4280,2021JJ40133)the Fundamentals and Basic of Applications Research Foundation of Guangdong Province(2019A1515110136).
文摘For the underwater long baseline(LBL)positioning systems,the traditional distance intersection algorithm simplifies the sound speed to a constant,and calculates the underwa-ter target position parameters with a nonlinear iteration.However,due to the complex underwater environment,the sound speed changes with time and space,and then the acoustic propagation path is actually a curve,which inevitably causes some errors to the traditional distance intersection positioning algorithm.To reduce the position error caused by the uncertain underwater sound speed,a new time of arrival(TOA)intersection underwater positioning algorithm of LBL system is proposed.Firstly,combined with the vertical layered model of the underwater sound speed,an implicit positioning model of TOA intersection is constructed through the constant gradient acoustic ray tracing.And then an optimization function based on the overall TOA residual square sum is advanced to solve the position parameters for the underwater target.Moreover,the particle swarm optimization(PSO)algorithm is replaced with the tra-ditional nonlinear least square method to optimize the implicit positioning model of TOA intersection.Compared with the traditional distance intersection positioning model,the TOA intersec-tion positioning model is more suitable for the engineering practice and the optimization algorithm is more effective.Simulation results show that the proposed methods in this paper can effectively improve the positioning accuracy for the underwater target.
文摘目的本研究旨在探讨BOPPPS联合案例为基础的学习方法(case-based learning,CBL)+教师主导式教学(lecture based learning,LBL)教学模式在心脏查体带教中的应用效果。方法以广东医科大学2020级本科临床医学专业的132名学生为研究对象,采用随机数字表法分为对照组(65人)和试验组(67人)。试验组男37人,女30人,年龄(22.37±0.91)岁;对照组男35人,女30人,年龄(22.68±0.69)岁。试验组采用BOPPPS联合CBL+LBL教学模式进行教学,而对照组采用传统的CBL+LBL教学法。最后采用问卷形式对教学效果进行评价。采用χ^(2)检验、独立样本t检验。结果试验组学生的满意度高于对照组[98.5%(66/67)比86.2%(56/65)],差异有统计学意义(P<0.05)。自我评价方面,在“是否激发学习兴趣、是否提高对学习重点难点的掌握、是否增强临床操作技能培养、教学组织的合理性及是否提高临床学习的兴趣”5个项目方面,试验组的学生评价均优于对照组(均P<0.05);在“培养临床思维能力、增强解决问题的能力、师生及医患的沟通和表达能力、学习效率及能力的提高、团队合作能力”5个项目方面,两组之间差异均无统计学意义(均P>0.05)。结论与传统CBL+LBL教学法相比,BOPPPS联合CBL+LBL教学模式,不仅可以提高学生的学习效率,激发其学习兴趣、积极性,同时也增强了他们的临床思维和临床操作技能。因此,这种教学模式具有很好的教学效果,值得推广和应用。
