With the development of high-speed and heavy-haul railway in China, problems like insufficient thickness of ballast bed and overlarge track stiffness are obvious. Ballast may break into small particles and their conta...With the development of high-speed and heavy-haul railway in China, problems like insufficient thickness of ballast bed and overlarge track stiffness are obvious. Ballast may break into small particles and their contact status will deteriorate under cyclic loading, resulting in ballast degradation. Discrete element method(DEM) was used to research improved performance of ballast bed using elastic sleeper. Clusters were generated by bonding spheres to model real ballasts, while broken bonds were utilized to distinguish breakage. Two kinds of ballast beds with elastic sleeper and conventional sleeper were established, respectively. After applying cyclic loading to the models, differences of mechanical properties between two models were analyzed by contrasting their dynamic behavior indexes, such as particle contact force, sleeper settlement, vibration velocity and acceleration, breakage characteristic. The results illustrate that compared with conventional sleeper, elastic sleeper increases sleeper settlement, while reduces ballast vibration and contact force between particles, which could depress ballast breakage.展开更多
目的:基于PatSnap数据库计量分析,研究全球针灸相关专利的发展现状,以期为针灸专利的发展提供参考和建议。方法:通过检索智慧芽(PatSnap)数据库2004—2022年全球范围内针灸领域专利信息,对专利的申请趋势、地域分布、相关技术、主要发...目的:基于PatSnap数据库计量分析,研究全球针灸相关专利的发展现状,以期为针灸专利的发展提供参考和建议。方法:通过检索智慧芽(PatSnap)数据库2004—2022年全球范围内针灸领域专利信息,对专利的申请趋势、地域分布、相关技术、主要发明人及主题词等进行分析。结果:共检索到针灸领域专利101343件,全球针灸专利申请量、授权量及授权占比总体呈上升趋势;我国是针灸专利申请量最多的国家,其次为韩国、日本;国内广东省、山东省和江苏省在针灸领域专利申请量靠前;A61H39专利技术类型占比最多;国内左点实业(湖北)有限公司、湖南中医药大学和成都中医药大学为主要申请人;国际上刘泰宇(■)、萨哈罗夫·康斯坦丁·谢尔盖耶维奇(SAKHAROV KONSTANTIN SERGEEVICH)和一心株式会社(■)为主要申请人;技术热点主要集中在立体图、多功能、医疗器械、点火针、便携式等。针灸医疗器械的发明整合创造是热点和高层次创新点。结论:目前我国针灸专利整体保持领先优势,今后仍需加强国内外交流合作;强化专利技术创新,提升专利质量和科技水平;优化专利申请布局,密切校院企合作,促进成果转化;促进多学科交叉融合创新。展开更多
基金Project(U1234211)supported by the National Natural Science Foundation of ChinaProject(2013G009-B)supported by China Railway Corporation
文摘With the development of high-speed and heavy-haul railway in China, problems like insufficient thickness of ballast bed and overlarge track stiffness are obvious. Ballast may break into small particles and their contact status will deteriorate under cyclic loading, resulting in ballast degradation. Discrete element method(DEM) was used to research improved performance of ballast bed using elastic sleeper. Clusters were generated by bonding spheres to model real ballasts, while broken bonds were utilized to distinguish breakage. Two kinds of ballast beds with elastic sleeper and conventional sleeper were established, respectively. After applying cyclic loading to the models, differences of mechanical properties between two models were analyzed by contrasting their dynamic behavior indexes, such as particle contact force, sleeper settlement, vibration velocity and acceleration, breakage characteristic. The results illustrate that compared with conventional sleeper, elastic sleeper increases sleeper settlement, while reduces ballast vibration and contact force between particles, which could depress ballast breakage.
文摘目的:基于PatSnap数据库计量分析,研究全球针灸相关专利的发展现状,以期为针灸专利的发展提供参考和建议。方法:通过检索智慧芽(PatSnap)数据库2004—2022年全球范围内针灸领域专利信息,对专利的申请趋势、地域分布、相关技术、主要发明人及主题词等进行分析。结果:共检索到针灸领域专利101343件,全球针灸专利申请量、授权量及授权占比总体呈上升趋势;我国是针灸专利申请量最多的国家,其次为韩国、日本;国内广东省、山东省和江苏省在针灸领域专利申请量靠前;A61H39专利技术类型占比最多;国内左点实业(湖北)有限公司、湖南中医药大学和成都中医药大学为主要申请人;国际上刘泰宇(■)、萨哈罗夫·康斯坦丁·谢尔盖耶维奇(SAKHAROV KONSTANTIN SERGEEVICH)和一心株式会社(■)为主要申请人;技术热点主要集中在立体图、多功能、医疗器械、点火针、便携式等。针灸医疗器械的发明整合创造是热点和高层次创新点。结论:目前我国针灸专利整体保持领先优势,今后仍需加强国内外交流合作;强化专利技术创新,提升专利质量和科技水平;优化专利申请布局,密切校院企合作,促进成果转化;促进多学科交叉融合创新。
