Four basic components of the solar radio emission: the quiet sun, the slowly varying component (SVC), the radio burst and the ultra-fast varying component (UFVC) are studied. As their six characteristic parameters: ra...Four basic components of the solar radio emission: the quiet sun, the slowly varying component (SVC), the radio burst and the ultra-fast varying component (UFVC) are studied. As their six characteristic parameters: radiation source, brightness temperature, radiation lifetime, polarized radiation, radiation mechanism, and character of superposition are affirmed.展开更多
本文研究了一个包含波动CISK(Convective Instability of the Second Kind)机制的扰动方程数值模式中,基本气流对低频振荡数值模拟的影响。结果显示,当基本气流为纬向均匀风场U时,振荡周期随U的增加而减小:当U取2 m s-1时,周期从50~60 ...本文研究了一个包含波动CISK(Convective Instability of the Second Kind)机制的扰动方程数值模式中,基本气流对低频振荡数值模拟的影响。结果显示,当基本气流为纬向均匀风场U时,振荡周期随U的增加而减小:当U取2 m s-1时,周期从50~60 d减小到30 d;当U减小到-1 m s-1时,振荡周期增加为70~80 d。这是由于低频振荡是从西向东传播,西风基本气流能加快扰动东传,反之东风基本气流会抑制扰动东传,使振荡周期增加。同时,模式中的边界层顶出现误差时,模拟结果会有敏感的响应。若边界层顶取值比标准值高,对流加热反馈作用过大,出现扰动增长过快的现象,传播到80°~90°E附近时,扰动不再继续传播,而是无限增长;而边界层顶取值比标准值低时,对流加热反馈过小,扰动增长小且衰减加快,扰动传播不远便耗散到零,扰动循环周期表现为热源的周期。展开更多
三维参数化、可视化设计是现代机械设计的发展趋势之一.在AutoCAD软件的二次开发工具VBA(visual basic for application)中,开发了刨齿刀三维参数化和可视化设计软件.在AutoCAD软件中进行刨齿刀三维参数化建模,利用生成的刨齿刀三维实...三维参数化、可视化设计是现代机械设计的发展趋势之一.在AutoCAD软件的二次开发工具VBA(visual basic for application)中,开发了刨齿刀三维参数化和可视化设计软件.在AutoCAD软件中进行刨齿刀三维参数化建模,利用生成的刨齿刀三维实体模型,在Pro/Engineer,ANSYS软件中进行刨齿刀有限元分析.制造了硬齿面圆锥直齿轮刨齿刀,对刀具的磨损进行分析,为刀具的快速开发提供条件.展开更多
文摘Four basic components of the solar radio emission: the quiet sun, the slowly varying component (SVC), the radio burst and the ultra-fast varying component (UFVC) are studied. As their six characteristic parameters: radiation source, brightness temperature, radiation lifetime, polarized radiation, radiation mechanism, and character of superposition are affirmed.
文摘本文研究了一个包含波动CISK(Convective Instability of the Second Kind)机制的扰动方程数值模式中,基本气流对低频振荡数值模拟的影响。结果显示,当基本气流为纬向均匀风场U时,振荡周期随U的增加而减小:当U取2 m s-1时,周期从50~60 d减小到30 d;当U减小到-1 m s-1时,振荡周期增加为70~80 d。这是由于低频振荡是从西向东传播,西风基本气流能加快扰动东传,反之东风基本气流会抑制扰动东传,使振荡周期增加。同时,模式中的边界层顶出现误差时,模拟结果会有敏感的响应。若边界层顶取值比标准值高,对流加热反馈作用过大,出现扰动增长过快的现象,传播到80°~90°E附近时,扰动不再继续传播,而是无限增长;而边界层顶取值比标准值低时,对流加热反馈过小,扰动增长小且衰减加快,扰动传播不远便耗散到零,扰动循环周期表现为热源的周期。
文摘三维参数化、可视化设计是现代机械设计的发展趋势之一.在AutoCAD软件的二次开发工具VBA(visual basic for application)中,开发了刨齿刀三维参数化和可视化设计软件.在AutoCAD软件中进行刨齿刀三维参数化建模,利用生成的刨齿刀三维实体模型,在Pro/Engineer,ANSYS软件中进行刨齿刀有限元分析.制造了硬齿面圆锥直齿轮刨齿刀,对刀具的磨损进行分析,为刀具的快速开发提供条件.