2008年4月中国制造业信息化第37卷第7期 表6负判断矩阵中元素向量出现正值符合要求,从而可以实现对产品外型的评价和筛 选,对产品外型设计具有一定的实用价值。如果把 NURBS的数据点看作参数,这种改进思想对其他 100090)∞0.0参数化的几何表达方法也具有一定的参考价值。 2(-10410,0)(-104100)(244100(24,4100) ,0)(95,0,1)65500)(560,0) 参考文献 Apllications, 1991, 11(1): 55-71 3结束语 12]方顾李季军,陆亚文.一种用于模具设计的 NURBS曲面 由以上的理论分析和实验结果可知,本文提出 造型系统设计方案[].模具工业,200632(2):18-21 的改进 NURBS表达方法可以判断产品外型设计3】陈军,崔汉国刘建军复杂船体曲面NURS造型技术的 研究与实现].计算机工程,2005,31(1):201-202 的合理性,只要能对产品外型的取值范围进行恰当(4]许平,田红旗,姚曙光流线型列车头部结构设计方法门 的限定,就可以获得比较好的判断效果,而且,由于 中国铁道科学,2006,27(1):78-82. 取值范围也可以是函数,所以它具有相当的灵活5]韩宝玲罗庆生,黎臻荣采用 NURBS进行汽车壳体计算机 性,为进一步精确表达设计要求提供了可能。 拟实外型的方法[J]机械设计与制造,2007,7(7):69-70 6]施法中计算机辅助几何设计与非均匀有理B样条[M].北 这种方法可以方便地判断改变后的曲面是否 京:高等教育出版社,2000 A Surface Re presentation Based on NURBS and Its Application An Yan fei-. QIU Ho (1. Xi'an Qixin Software Ltd. Co., Shaanxi Xi'an, 710076, China) (2. Dalian University, Liaoning Dalian, 116622, China) (3. Shantou University, Guangdong Shantou, 515063, China) Abstract It proposes a surface representation based on NURBS, which can test the validity of product design result. This method reorganizes the disorderly data of points in original NURBS, uses a differ- matrix and a criterion- matrix to represent geometric constraint, judges the requirement of design with the judgment-mar trix. It int roduces the common steps for representing and judging existed NUrBs surfaces, shows the shape car design of its front engine crust Key words NURBS; Differ- matrix; Criterion- matrix, J udgment-matrix (上接第40页) 2]伍晓宇,陈锦盛,王志勇,等.一个面向制造业的生产作业计 划调度系统[U]中国机械工程,2002,13(16):1423-1426 The Genetic Algorithm for Job- Shop Based on Real and Virtual Gene Stands WU Xiao- yu, WANG Zhi- yong, WU Xu-yi (1. Shenzhen University, Guangdong Shenzhen, 518060, China) 2. Shenzhen Institute of Standard Technology, Guangdong Shenzhen, 518033, China) Abstract It presents an improved genetic al gorithm using the idea of real and virtual gene stands for job hop. This met hod is self-adaptable in crossover and mutation, simple in encoding, evolving in small group converging in low generation and strong global searching. The example proves that the algorithm can solve the practical scheduling problems for job- shop and shorten the lead -time Key words: Shop Cont rol Scheduling; Genetic Algorithm; Optimization 201994-2008cHinaAcademicJournalElectronicPUblishingHouseaLlrightsreservedhttp:/hnnv.cnkiner表 6 负判断矩阵中元素向量出现正值 i j 1 2 3 4 1 (0 ,0 ,0 ,0) (0 ,0 ,0 ,0) (30 ,0 ,0 ,0) (30 ,0 ,0 ,0) 2 ( - 10 ,41 ,0 ,0) ( - 10 ,41 ,0 ,0) (24 ,41 ,0 ,0) (24 ,41 ,0 ,0) 3 (9 ,6 ,0 ,0) (9 ,6 ,0 ,1) (5 ,6 ,0 ,0) (5 ,6 ,0 ,0) 4 (0 ,0 ,0 ,0) (0 ,0 ,0 ,0) (15 ,0 ,0 ,0) (15 ,0 ,0 ,0) 3 结束语 由以上的理论分析和实验结果可知 ,本文提出 的改进 NURBS 表达方法可以判断产品外型设计 的合理性 ,只要能对产品外型的取值范围进行恰当 的限定 ,就可以获得比较好的判断效果 ;而且 ,由于 取值范围也可以是函数 ,所以它具有相当的灵活 性 ,为进一步精确表达设计要求提供了可能。 这种方法可以方便地判断改变后的曲面是否 符合要求 ,从而可以实现对产品外型的评价和筛 选 ,对产品外型设计具有一定的实用价值。如果把 NURBS 的数据点看作参数 ,这种改进思想对其他 参数化的几何表达方法也具有一定的参考价值。 参考文献 : [ 1 ] Piegl L . On NURBS :a survey[J ] . IEEE Computer Graphics & Apllications , 1991 ,11 (1) :55 - 71. [2 ] 方 顾 ,李季军 ,陆亚文. 一种用于模具设计的 NURBS 曲面 造型系统设计方案[J ] . 模具工业 ,2006 ,32 (2) :18 - 21. [ 3 ] 陈 军 ,崔汉国 ,刘建军. 复杂船体曲面 NURBS 造型技术的 研究与实现[J ] . 计算机工程 ,2005 ,31 (1) :201 - 202. [ 4 ] 许 平 ,田红旗 ,姚曙光. 流线型列车头部结构设计方法[J ] . 中国铁道科学 ,2006 ,27 (1) :78 - 82. [ 5 ] 韩宝玲 ,罗庆生 ,黎臻荣. 采用 NURBS 进行汽车壳体计算机 拟实外型的方法[J ] . 机械设计与制造 , 2007 ,7 (7) : 69 - 70. [ 6 ] 施法中. 计算机辅助几何设计与非均匀有理 B 样条[ M ] . 北 京 :高等教育出版社 ,2000. A Surface Representation Based on NURBS and Its Application AN Yan - ping 1 , YI Peng - fei2 , Q IU Hong - jun3 (1. Xi’an Qixin Software Ltd. Co. , Shaanxi Xi’an , 710076 , China) (2. Dalian University , Liaoning Dalian , 116622 , China) (3. Shantou University , Guangdong Shantou , 515063 , China) Abstract :It proposes a surface representation based on NURBS , which can test the validity of product design result . This method reorganizes the disorderly data of points in original NURBS , uses a differ - matrix and a criterion - matrix to represent geometric constraint , judges the requirement of design with the judgment - ma2 trix. It introduces the common steps for representing and judging existed NURBS surfaces , shows the shape car design of its front engine crust . Key words :NURBS ; Differ - matrix ; Criterion - matrix ; J udgment - matrix (上接第 40 页) [2 ] 伍晓宇 ,陈锦盛 ,王志勇 ,等. 一个面向制造业的生产作业计 划调度系统[J ] . 中国机械工程 ,2002 ,13 (16) :1 423 - 1 426. The Genetic Algorithm for Job - Shop Based on Real and Virtual Gene Stands WU Xiao - yu 1 , WAN G Zhi - yong 2 , WU Xu - yi2 (1. Shenzhen University , Guangdong Shenzhen , 518060 , China) (2. Shenzhen Institute of Standard Technology , Guangdong Shenzhen , 518033 , China) Abstract :It presents an improved genetic algorithm using the idea of real and virtual gene stands for job - shop . This method is self - adaptable in crossover and mutation , simple in encoding , evolving in small group , converging in low generation and strong global searching. The example proves that the algorithm can solve the practical scheduling problems for job - shop and shorten the lead - time. Key words :Shop Control ; Scheduling ; Genetic Algorithm ; Optimization 44 2008 年 4 月 中国制造业信息化 第 37 卷 第 7 期 © 1994-2008 China Academic Journal Electronic Publishing House. All rights reserved. http://www.cnki.net