航海仿真课件NavSim01祥解.pptVIP

Simulation Technology John Shi Chaojian Ways to study a system Course Philosophy Examine Several Modern Techniques Understand, practically and theoretically, how the techniques perform on representative, but real, applications Why Theory? Guarantees, given assumptions, that the method will always work. Can help debug programs. The Theory can tell you what to do in practice. Examples 1. Queuing System A customer who arrives and finds the server idel enters service immediately. A customer who arrives and finds the server busy joins the end of a single queue. Upon completing service for a customer, the server choose a customer from the queue (if any) in a FIFO manner. Suppose interarrival time and service time are independent and identically distributed(IID). Examples 2. Inventory System Times between demands 0.1 month Demand size {1,2,3,4} with probability {1/6,1/3,1/3,1/6} Order at beginning of each month. Z items cost=32+3*Z. if Z=0, cost=0. Arrival time 0.5 t0 1 month uniformly distributed. Use stationary policy (if Is, Z=S-I; else Z=0.) Holding cost 1/(item·month); backlog cost 5/((item·month). Examples Compare policies Examples 3. Four Stroke Engine Examples 4. Power Distribution for a VLSI Circuit Examples Load Bearing Space Frame Thermal Analysis Does the engine get too hot ! ? The heat generated by the gas burning in the cylinders must be conducted through the engine block to a wide enough surface area that the heat can be dissipated. Ifnot, the engine block temperature will rise too high and the block will melt. 仿真技术定义 以相似原理、控制理论、计算机技术、信息技术及其应用领域的专业技术为基础，以计算机和各种物理效应设备为工具，利用数学模型或部分实物对实际的或设想的系统进行动态试验研究的一门综合性技术。 仿真分类 按被仿真对象性质可分为: 连续系统仿真(Continuous System Simulation) 离散事件系统仿真(Discrete Events System Simulation) 按功能用途可分为: 工程仿真(Engineering Simulation) 训练仿真(Training Simulation)； 按应用领域可划分为: 工程领域仿真 非工程领域仿真 按虚实结合的程度又可分为: 结构仿真(Constructive Simulation) 虚拟仿真(Virtual Simulation) 实况仿真(Live Simulation)。 工程应用领域连续系统仿真分类 数学仿真(Mathematical Simulation) 硬件在回路仿真(Hardwar