薄壁框体零件优质高效加工工艺方法

以航空航天中常用的薄壁框体类零件为例,在提高加工效率和保证加工质量的前提下,研究走刀路径和装夹方案的优选方法,提出了针对薄壁框体类零件的加工策略,即粗加工装夹力应垂直于框体的最长边,刀具平行于框体最长边快速走刀是最高效的走刀路径,尽可能选用小的精加工余量可最大限度地提高框体零件的加工效率.制定了针对框体类零件的精加工余...     

基于Web的纺织品销售管理系统的研制

为某纺织企业研制了一个基于Web的销售管理系统，系统基于B／S结构，采用ASP技术进行开发；介绍了系统的功能目标、总体结构及数据库设计，并讨论了系统开发与实施过程中所采用的关键技术。     

海工装备生产车间可重构制造单元动态布局方法

为满足海工装备品种多、批量小的生产特点,具有多个可重构制造单元的海工装备生产车间需要及时做出布局调整。针对此问题,将改进非支配排序的遗传算法-II(NSGA-II)应用于车间的设备动态布局优化过程,结果显示,求得的Pareto前沿具有良好的分布性。建立了相应的求解数学模型,并用Matlab软件进行求解。结合实例采用仿真软件对求解的布局结果建立仿真模型,并进行仿真分析,为设备布局的选用和改进提供决策依据。     

Event-driven Dynamic and Intelligent Scheduling for Agile Manufacturing Based on Immune Mechanism and Expert System

Based on the biological immune concept, immune response mechanism and expert system, a dynamic and intelligent scheduling model toward the disturbance of the production such as machine fault, task insert and cancel etc. is proposed. The antibody generation method based on the sequence constraints and the coding rule of antibody for the machining procedure is also presented. Using the heuristic antibody generation method based on the physiology immune mechanism, the validity of the scheduling optimization is improved, and based on the immune and expert system under the event-driven constraints, not only Job-shop scheduling problem with multi-objective can be solved, but also the disturbance of the production be handled rapidly. A case of the job-shop scheduling is studied and dynamic optimal solutions with multi-objective function for agile manufacturing are obtained in this paper. And the event-driven dynamic rescheduling result is compared with right-shift rescheduling and total rescheduling.     

极大径厚比薄壁件的加工变形仿真与试验研究

针对径厚比极大的铝合金薄壁件易加工变形的问题,开展基于有限元显示动力学的铣削过程仿真研究.在相同材料去除率下,分析转速、切深及每齿进给量的组合条件对切削力与变形的影响;采用单侧独立切削与双侧交替切削两种加工路径,在薄壁件不同高度处进行切削变形仿真计算.结果表明:较高的转速、较小的切深及适当的每齿进给量可保证加工效率并减...     

Study on the Back Rest System of Looms

Periodic variations of warp tension during a weaving cycle result in corresponding change of back rest position, and the oscillation of back rest affects the fluctuation of warp yarn in return. A mechanical model of back rest system of looms is presented on basis of auto control theory, and the factors affecting the dynamic performance of the back rest are analyzed. In the model, warp yarn is regarded as a viscoelastic medium, and the adjustable parameters and the adjusting range of the back rest system are increased, so the loom's applicability for the fabric's variety is enhanced. Finally, the methods of designing and adjusting the back rest are discussed, and a trend of back rest system development is given.     

The Information Modeling and Intelligent Optimization Method for Logistics Vehicle Routing and Scheduling with Multi-objective and Multi-constraint

The vehicle routing and scheduling (VRS)problem with multi-objective and multi-constraint is analyzed, considering the complexity of the modern logistics in city economy and daily life based on the system engineering. The objective and constraint includes loading,the dispatch and arrival time, transportation conditions,total cost, etc. An information model and a mathematical model are built, and a method based on knowledge and biologic immunity is put forward for optimizing and evaluating the programs dimensions in vehicle routing and scheduling with multi-objective and multi-constraints. The proposed model and method are illustrated in a case study concerning a transport network, and the result shows that more optimization solutions can be easily obtained and the method is efficient and feasible. Comparing with the standard GA and the standard GA without time constraint,the computational time of the algorithm is less in this paper.And the probability of gaining optimal solution is bigger and the result is better under the condition of multi-con,traint.     

Job-shop Scheduling with Multi-objectives Based on Genetic Algorithms

The technology of production planning and scheduling is one of the critical technologies that decide whether the automated manufacturing systems can get the expected economy. Job shop scheduling belongs to the special class of NP-hard problems. Most of the algorithms used to optimize this class of problems have an exponential time; that is, the computation time increases exponentially with problem size. In scheduling study, makespan is often considered as the main objective. In this paper, makespan, the due date request of the key jobs, the availability of the key machine, the average wait-time of the jobs, and the similarities between the jobs and so on are taken into account based on the application of mechanical engineering. The job shop scheduling problem with multi-objectives is analyzed and studied by using genetic algorithms based on the mechanics of genetics and natural selection. In this research, the tactics of the coding and decoding and the design of the genetic operators, along with the des