nodal pattern

The optimization method is used to design a structure subject to the constraints of multiple frequencies, nodal lines, mass centre and the total weight.

在给定了多阶固有频率、振型节线位置、结构的质量与质心等要求条件下，运用优化方法进行结构动力学设计，文中还给出了一种振型节线的直接搜索法，且对一个实际的机翼颤振模型进行了设计。

cos- mopolitan technical problems arisen in the process of precisely screening the moist glutinous fines of the raw coal(6 mm),proposes an essential solution,and provides a new kind of the screening machine;Low frequen- cy,large amplitude,large vibrating direction angle,sectional vibration,even-depth screening,large line vi- bration screen,large amplitude arthropod screen.

在煤炭加工行业中,针对潮湿粘性细粒原煤深度筛分(6 mm)中出现的筛孔堵塞、筛分效率低下等世界性技术难题,提出了根本的解决方案,提供了一种新型的筛分机械：低频率、高振幅、大振动方向角、分节振动和等厚筛分的大型直线振动筛-大振幅节肢筛。