针对塔筒在复杂荷载作用以及不同工况下的结构响应问题,采用建筑信息模型(Building Information Modeling, BIM)+有限元分析(Finite Element Analysis, FEA)的方法,对某2 MW大型水平轴风力发电机组塔筒进行结构性能分析。首先参数化建...针对塔筒在复杂荷载作用以及不同工况下的结构响应问题,采用建筑信息模型(Building Information Modeling, BIM)+有限元分析(Finite Element Analysis, FEA)的方法,对某2 MW大型水平轴风力发电机组塔筒进行结构性能分析。首先参数化建立风力发电机组的BIM模型并对塔筒荷载进行分析计算,然后将塔筒BIM模型转换为有限元模型,最后在有限元软件ANSYS中对塔筒进行仿真分析。结果显示:塔筒最大应力出现在底部,塔筒顶部的位移最大。塔筒前六阶固有频率均不会与塔筒产生共振,且塔筒的固有频率随塔筒高度的增加而减小。随着塔筒顶部质量增加,塔筒的固有频率减小,塔筒顶部质量变化对塔筒的应力和顶部位移影响较小,对塔筒的固有频率影响较大。研究表明BIM+FEA方法能够为风力发电机组塔筒结构安全分析提供新思路,在风力发电机组塔筒的设计和运维中进行安全预警,为管理者决策提供有效数据信息。展开更多
艾滋病、梅毒和乙肝可经由孕产妇向胎儿传播,对母婴健康造成威胁;但目前对于感染孕产妇及其所生婴幼儿已有高效、经济、简便的方法进行预防和干预,使得消除艾滋病、梅毒和乙肝母婴传播成为可能。2010年,我国在全球率先提出整合的预防艾...艾滋病、梅毒和乙肝可经由孕产妇向胎儿传播,对母婴健康造成威胁;但目前对于感染孕产妇及其所生婴幼儿已有高效、经济、简便的方法进行预防和干预,使得消除艾滋病、梅毒和乙肝母婴传播成为可能。2010年,我国在全球率先提出整合的预防艾滋病、梅毒和乙肝母婴传播策略并建立服务网络,2011年发布《预防艾滋病、梅毒和乙肝母婴传播工作实施方案》,在2015年实现了预防三病母婴传播全国全覆盖的服务[1]。2014年,WHO开始在全球范围内开展消除艾滋病和梅毒母婴传播的认证[2],并在2021年将乙肝纳入消除母婴传播的认证流程[3]。WHO把消除母婴传播(Elimination of mother-to-child transmission,EMTCT)定义为将婴幼儿和儿童的艾滋病、梅毒和乙肝新发感染病例数量降至不再构成公共卫生问题的水平[3]。展开更多
The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic c...The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic complementarity of multiple bands are crucial for enhancing the spectrum efficiency,reducing network energy consumption,and ensuring a consistent user experience.This paper investigates the present researches and challenges associated with deployment of multi-band integrated networks in existing infrastructures.Then,an evolutionary path for integrated networking is proposed with the consideration of maturity of emerging technologies and practical network deployment.The proposed design principles for 6G multi-band integrated networking aim to achieve on-demand networking objectives,while the architecture supports full spectrum access and collaboration between high and low frequencies.In addition,the potential key air interface technologies and intelligent technologies for integrated networking are comprehensively discussed.It will be a crucial basis for the subsequent standards promotion of 6G multi-band integrated networking technology.展开更多
文摘针对塔筒在复杂荷载作用以及不同工况下的结构响应问题,采用建筑信息模型(Building Information Modeling, BIM)+有限元分析(Finite Element Analysis, FEA)的方法,对某2 MW大型水平轴风力发电机组塔筒进行结构性能分析。首先参数化建立风力发电机组的BIM模型并对塔筒荷载进行分析计算,然后将塔筒BIM模型转换为有限元模型,最后在有限元软件ANSYS中对塔筒进行仿真分析。结果显示:塔筒最大应力出现在底部,塔筒顶部的位移最大。塔筒前六阶固有频率均不会与塔筒产生共振,且塔筒的固有频率随塔筒高度的增加而减小。随着塔筒顶部质量增加,塔筒的固有频率减小,塔筒顶部质量变化对塔筒的应力和顶部位移影响较小,对塔筒的固有频率影响较大。研究表明BIM+FEA方法能够为风力发电机组塔筒结构安全分析提供新思路,在风力发电机组塔筒的设计和运维中进行安全预警,为管理者决策提供有效数据信息。
文摘艾滋病、梅毒和乙肝可经由孕产妇向胎儿传播,对母婴健康造成威胁;但目前对于感染孕产妇及其所生婴幼儿已有高效、经济、简便的方法进行预防和干预,使得消除艾滋病、梅毒和乙肝母婴传播成为可能。2010年,我国在全球率先提出整合的预防艾滋病、梅毒和乙肝母婴传播策略并建立服务网络,2011年发布《预防艾滋病、梅毒和乙肝母婴传播工作实施方案》,在2015年实现了预防三病母婴传播全国全覆盖的服务[1]。2014年,WHO开始在全球范围内开展消除艾滋病和梅毒母婴传播的认证[2],并在2021年将乙肝纳入消除母婴传播的认证流程[3]。WHO把消除母婴传播(Elimination of mother-to-child transmission,EMTCT)定义为将婴幼儿和儿童的艾滋病、梅毒和乙肝新发感染病例数量降至不再构成公共卫生问题的水平[3]。
基金supported by China’s National Key R&D Program(Project Number:2022YFB2902100)。
文摘The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic complementarity of multiple bands are crucial for enhancing the spectrum efficiency,reducing network energy consumption,and ensuring a consistent user experience.This paper investigates the present researches and challenges associated with deployment of multi-band integrated networks in existing infrastructures.Then,an evolutionary path for integrated networking is proposed with the consideration of maturity of emerging technologies and practical network deployment.The proposed design principles for 6G multi-band integrated networking aim to achieve on-demand networking objectives,while the architecture supports full spectrum access and collaboration between high and low frequencies.In addition,the potential key air interface technologies and intelligent technologies for integrated networking are comprehensively discussed.It will be a crucial basis for the subsequent standards promotion of 6G multi-band integrated networking technology.
