一种新的多版本增创算法  

A New Multiple Versions Incremental Creation Algorithm

作　　者：杨君[1] 窦万峰[2] 

机构地区：[1]南京师范大学数学与计算机科学学院,南京210097 [2]南京师范大学虚拟地理环境教育部重点实验室,南京210097

出　　处：《计算机学报》2008年第4期702-710,共9页Chinese Journal of Computers

基　　金：江苏省高校自然科学基金(07KJD520112)资助~~

摘　　要：现有的对象复制技术是实时协同图形编辑系统中符合一致性模型的并发控制策略,但难以解决非几何属性以及三维绘图系统中的并发冲突情况.介绍了一个全新的一致性维护模型——基于版本复制的多版本技术,当并发操作发生冲突时,利用简化规则从目标版本派生出叶子物理版本,分别应用冲突操作到不同的叶子版本,有效地解决了非调和冲突操作的意愿保证.通过研究多版本技术的相关支持算法,在算法MOVIC的基础上,从各个冲突操作的最大共同相容操作着手,提出了基于相容冲突组的快速多版本增创算法FMVIC(Fast Multiple Versions Incremental Creation),减少了相容操作的比较次数,缩小了去冗余操作的范围.The multi versioning technique based on object replication strategy can meet consistency model while the conflict operations occur in the cooperative graphics editing systems（CG-ES）, but it does not efficiently solve conflict between non-geometry attribute operations and complex graphics objects. A new distributed multi-versioning model based on version replication is proposed for consistency maintenance of discordant conflicting operations according to the conflicting features and types of concurrent operations in CGES. To guarantee intention of conflicting operations, leaf-versions must be replicated from the original version based on the reduce strategy, and then applying conflicting operations to the corresponding object of the different replicated versions. The leaf-versions can be created by MOVIC algorithm in which the comparisonnumber of compatible operations is too much. A Fast Multiple Versions Incremental Creation （FMVIC） algorithm based on the compatible and conflict group is presented in this paper. The final versions constructed by the FMVIC algorithm is the same as that constructed by the MOVIC algorithm, but it can decrease the comparison-number of compatible operations and narrow the scope of comparison operations for the removing redundant versions.

关 键 词：协同图形编辑 并发控制 版本复制 一致性模型 相容冲突组 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]