Solving resource-constrained multiple project scheduling problem using timed colored Petri nets

To solve the resource-constrained multiple project scheduling problem (RCMPSP) more effectively, a method based on timed colored Petri net (TCPN) was proposed. In this methodology, firstly a novel mapping mechanism between traditional network diagram such as CPM (critical path method)/PERT (program evaluation and review technique) and TCPN was presented. Then a primary TCPN (PTCPN) for solving RCMPSP was modeled based on the proposed mapping mechanism. Meanwhile, the object PTCPN was used to simulate the multiple projects scheduling and to find the approximately optimal value of RCMPSP. Finally, the performance of the proposed approach for solving RCMPSP was validated by executing a mould manufacturing example.     

台风移动的理论分析

本文主要是从描述大气运动的涡度控制方程出发,通过一些常规的假设,运用计算技巧代入原方程并化简,得到频散关系式,由此式得到台风移速公式,从理论上分析了台风的移动情况,从而为台风的移动情况预报提供了理论依据,为海上航行安全提供了一定的气象服务保障.     

2002年天津沿海地区春季首场大雾分析

春季大雾是影响天津沿海地区海上航运、港口作业的一个重要因素，本文利用常规气象资料分析了本场平流雾产生的环流背景、低空风场、地面形势及塘沽站、上游站天气要素等特点，认为高空玮向环流平直、低空有暖平流、地面风向风速适宜、气流上游水气条件较好是形成此次大雾的主要原因。     

Engineering design optimization based on intelligent response surface methodology

An intelligent response surface methodology （IRSM） was proposed to achieve the most competitive metal forming products, in which artificial intelligence technologies are introduced into the optimization process. It is used as simple and inexpensive replacement for computationally expensive simulation model. In IRSM, the optimal design space can be reduced greatly without any prior information about function distribution. Also, by identifying the approximation error region, new design points can be supplemented correspondingly to improve the response surface model effectively. The procedure is iterated until the accuracy reaches the desired threshold value. Thus, the global optimization can be performed based on this substitute model. Finally, we present an optimization design example about roll forming of a ＂U＂ channel product.