the finite derwent meThod Ir position of boundary conditions(olis plcewent) We had obtained the aesewbed finite element eeve Kik2∞ Kht K Ki

Which of the following are real problems with the ritz method 1. Selection of basis functions for general ge- metres 2. Lack of systematic procedure to compute stiff atrix and forcing terms

美国麻省理工大学：《结构分析与设计技术》教学资源（讲义）notes121

我们先从一种最简单、最容易理解的图形开始分析技术形态。横线或称盘局,就是图形 之中最基本的形状。图表虽然浅显又简单但横线的含义与启示却十分重要,能够确认某种投 资是横线走势,密切观察,一但发现盘局发生变化,把握买入卖出讯号,利润可能以数倍计 图1中的阿城钢铁股价,由98年9月至12月初的走势基本呈一条横线的形状,价位在 4.5元左右,每日波动幅度不超过两三个价位,与12月中旬起逐步飙升至18元的行情不可 同日而语。9月至12月的图形形状就是“横线”,技术上又称盘局

4.3 样本总容量n的确定 4.4 分层的若干技术问题

美国麻省理工大学：《结构分析与设计技术》教学资源（讲义）notes122

What, in your opinion is the value of ritz's method? 1. Some. It is fraught with difficult make it almost impossible to apply to the challenging problems of design of moder aerospace structures

Principle of Virtual Displacements Consider a body in equilibrium. We know that the stress field must satisfy the differential equations of equilibrium. Multiply the differential equations of equilibrium by an \arbitrary\displacement field T

原子簇(团簇) cluster C660 Roundest and most symmetrical molecule known to man Compressed becomes stronger than diamond Third major form of pure carbon Heat resistance and =0.77nm electrical conductivity

Unit #9 -Calculus of Variations Let u be the actual configuration of a structure or mechanical system. u satisfies the displacement boundary conditions: u=u* on Su. Define