Block cipher is an important branch of cryptology, it has many attractive features such as high rates, easy for standardization, and efficient for both software and hardware implementations . block ciphers are usually core components in information and internet security for data encryption, data signature, authentication and key management 分组密码是密码学的一个重要分支，它具有速度快、易于标准化和便于软硬件实现等特点，通常是信息与网络安全中实现数据加密、数字签名、认证及密钥管理的核心体制。
Er fluids, as a kind of smart material, possibly be revolutionary in several areas of industry and technology due to their attractive features of rapid ( within ms order ), reversible and dramatic changes in rheologic properties upon applied electric field of kilo-voltage per millimeter order 电流变体在外加电场作用下能在毫秒级时间内发生明显的、可逆的流变响应，从而被认为是“有可能使诸多工业部门发生变革的一种智能材料”，它是材料科学和液态物理等领域的一大研究热点和学科前沿。
Mobile agent ( ma ), compared with traditional c / s model, is a novel network computing paradigm, which has some attractive features, such as dynamic adaptability, heterogeneity, robusticity and fault tolerance . it can effectively reduce the network traffic and delay, and be independent of different network protocols as well as support mobile devices 移动agent作为一种新的网络计算模型，与传统的客户服务器模型相比，具有动态适应性、异构性、健壮性和容错性，在分布式移动应用中可以降低网络流量、减少网络延迟、封装网络协议差异、支持移动设备等。
