opyright Nancy Leveson, Sept. 1999 Stage 1: Forming Team members begin to discover what behaviors are acceptable Usually highly unstructured environment Attempt to identify tasks, how to accomplish them Decisions on what information is needed Hesitant participation

Can programming language influence correctness? anguages affect the way we think about problems The tools we use have a profound(and devious) influence on our thinking habits, and, therefore on our thinking abilities?

Reuse (Assume have source code, not a commercial product) Ariane 5. Therac-25. British AtC Expectation Significantly lower development costs and time. Amortize costs among all users or uses Assumptions

Formal design Reviews Associated with each of documentation phases Evaluate with respect to Customer requirements Prescribed standards and practices Contractual requirements

State Machine specifications Define behavior using states and transitions between states

（一）岩体边坡破坏 的主要类型： 平面滑动

一、应力路径的概念: 二、土体受力发生发展和变化的过程

(一) 自重应力情况 (二) 附加应力情况—孔压系数概念 1 . 侧限应力状态

第一节 土的压缩性 一. 侧限压缩实验

概 述 10.1 空气污染连续自动监测系统 10.2 水污染连续自动监测系统 10.3 遥感监测技术 10.4 简易监测方法