A radio frequency identification application for car theft prevention in parking lot management systems

Currently, there are many parking lot management systems in use; however, most of them are unsuited to the problem of car theft. For example, a thief can drive a jalopy into a parking lot, and because the gate does not have any mechanism to detect whether the driver is the owner of the car, the gate will be open according merely to whether the driver pays the parking fee. A thief can drive away with a luxurious car away using his own parking ticket. We propose a new scheme to prevent the car theft. We adopt radio frequency identification technology conforming to EPCglobal Class 1 Generation 2 to our scheme design. Our scheme supplies an easy, cheap and high security parking environment for customers and the parking management system. Copyright © 2012 John Wiley & Sons, Ltd.     

顾客延时离开的共享车位预订控制策略研究

基于车位共享用户未按约定时间离开而导致车位使用时间冲突的问题,构建了随机动态规划模型。通过模型,研究了平台的预订控制策略,并针对平台能否拒绝延时需求的情形,设计两种算法对模型进行求解,最后通过数值仿真验证了算法的有效性。研究结果表明：(1)随着预订周期的增加,平台的边际收益会先增加后减少,因此存在最优预订周期;(2)若平台可以决策延时需求是否被接受,则随着延时概率的增加,机会成本将减少,而平台服务率和车位利用率将增加;(3)若平台只能被动接受延时需求,则随着延时概率的增加,平台服务率将减少,而机会成本和车位利用率将增加。     

新型高压半超结功率MOSFET的优化设计

给出了一个完整的半超结MOS的设计方法,包括超结部分浓度的确定,电压支持层部分的深度和浓度的优化.借助二维器件仿真讨论了在原胞尺寸不变的情况下导通电阻和击穿电压的折中关系的优化方法.通过模拟得到了一个750 V,特征导通电阻为32 mΩ*cm2的半超结结构.结果表明在不增加外延次数,工艺成本和难度的情况下,深宽比为5半超结MOS的特征导通电阻比VDMOS的下降了64%,比超结MOS的下降了8%.