Teaching Objectives 1)understand the main idea(despite the many negative effects of virtual life the author prefers it to real life) and the structure of the text(contrast between virtual life and real life); -2)learn some rules of interpreting new vocabulary

Directions: In this part, you will hear ten short statements. The statements will be spoken only once. After each statement, there will be a pause. During the pause, you must read four choices marked A, B, C, and D, and decide which is the best answer. Then mark the corresponding letter on the Answer sheet with a single line through the center

1. understand the main idea (despite his wealth, Sam Walton remains down-home and devoted to his team) and the structure of the text; 2. appreciate the use of indirect description in portraying person: 3. grasp the key language points and grammatical structures in the text

一、前言 二、波的基本概念 三、平面简谐波方程 四、波动方程与波速 五、平均能流密度·声强与声压 六、波的叠加和千涉·驻波 七、多普勒效应

Section A Longing for a New Welfare System The Objective of the Teaching 1. Let the students grasp some new words and phrases 2. Learn the figurative language and how to describe some persons or some things. 3. Let the students have a better understanding of the life of the disabled

§1 机械波的产生和传播 §2 一维简谐波的表达式 §3 波动方程和波速 §4 波的能量 §5 惠更斯原理 §6 多普勒效应 §7 波的叠加 §8 驻波(standing wave) §9 波的干涉

Lead-in activities What is ethics in our country? Honesty and modest are two basic ethics in our country. A society with ethics is a society with prosperity, so is business. 2. By far, which country is the relatively clear country in the world? Why? Singapore. two possible reasons: near-perfect welfare system; high salary for all the working people

置换密码（列置换密码和周期置换密码） 代换密码（单表代换密码、多表代换密码和维尔姆密码） 典型传统密码的分析（统计分析法和明文-密文对分析法）

3.1运输问题的典例和数学模型 一、典例: 某食品公司经营糖果业务,公司下设三个工厂A1、A2、A3,四个销售门市部B1、B2、B3、B4。已知每天各自的生产量、销售量及调运时的单位运输费用情况。问:如何调运可使总费用最小?

本讲主要内容： 数字签名的简介 基于RSA数字签名 基于离散对数数字签名 ElGamal数字签名 Schnorr数字签名 DSA数字签名 基于ECC数字签名