Tao Yu的论文之一 "Service Selection Algorithms for Web Services with End-to-end QoS Constraints (ISeBM2005)"
Yu Tao
个人主页: http://link.ece.uci.edu/tyu/index.html
个人简历上介绍, 本科就读于成都电子科技大学(1995), 硕士是北邮(1998), PhD在University of California, Irvine(2002), 博士论文的题目是"QoS (Quality of Service) in Web Services: Architecture, Model and Algorithms"
她于05~07年在Web service selection with QoS constraints方面发表过一系列的论文:
T. Yu and K.J. Lin " Service Selection Algorithms for Web Services with End-to-end QoS Constraints", Journal of Information Systems and e-Business Management, Volume 3, Number 2, July 2005
T. Yu and K.J. Lin, " Service Selection Algorithms for Composing Complex Services with Multiple QoS Constraints", ICSOC2005
T. Yu and K.J. Lin, " Adaptive algorithms for Finding Replacement Services in Autonomic Distributed Business Processes." ISADS2005
T. Yu and K.J. Lin " A Broker-Based Framework for QoS-Aware Web Service Composition", EEE05
Tao Yu, Yue Zhang, Kwei-Jay Lin: Efficient algorithms for Web services selection with end-to-end QoS constraints. TWEB 1(1): (2007)
今天重读了一遍"Service Selection Algorithms for Web Services with End-to-end QoS Constraints (ISeBM2005)".
本文研究的是如何选择Web服务, 使得组合服务的整体QoS满足约束, 并且使效用值最大.
这篇论文对研究的问题做了一些简化:
(1) 只考虑sequantial composition model (这个是一个比较重大的简化)
(2) 只考虑具有一个QoS约束条件(delay)
使用了两种方式来解决问题: combinatorial approach, graph approach
在combinatorial approach中,
问题被建模为MCKP(多选择背包问题), 并使用了Exhausive search, dynamic programming, Pisinger这3种算法来求解.
这种方式的缺陷是无法对transmision delay和cost进行建模. 由于同一个service class内的不同service可以由不同的provider提供, 而不同的provider可以处于不同的网络, 因此service之间的transmission delay/cost是存在差异的, 但是在combinatorial approach中只能假定两个service之间的transmission delay/cost是一样的.
在graph approach中,
使用DAG进行建模(如果还有其他composition model ,比如parallel, 似乎很难用文中现有的建模方法), 经过转换, 将cost/benefit等参数映射到边上.
将问题建模成图论中的constrained shortest path问题.
使用了Constrained Bellman-Ford(CBF)和Constrained Shortest Path(CSP)算法来求解.
CBF算法是指数级的
其他注意点
(1) dominate relationship (S5.2.3, 算法1中提到)
两条路径a, b, 如果(a.utility >= b.utility) && (a.delay <= b.delay ), 则称路径a dominate 路径b, 即路径a在每一个方面都优于路径b.
(2) topological order
Definition: A numbering of the vertices of a directed acyclic graph such that every edge from a vertex numbered i to a vertex numbered j satisfies i<j.
个人主页: http://link.ece.uci.edu/tyu/index.html
个人简历上介绍, 本科就读于成都电子科技大学(1995), 硕士是北邮(1998), PhD在University of California, Irvine(2002), 博士论文的题目是"QoS (Quality of Service) in Web Services: Architecture, Model and Algorithms"
她于05~07年在Web service selection with QoS constraints方面发表过一系列的论文:
T. Yu and K.J. Lin " Service Selection Algorithms for Web Services with End-to-end QoS Constraints", Journal of Information Systems and e-Business Management, Volume 3, Number 2, July 2005
T. Yu and K.J. Lin, " Service Selection Algorithms for Composing Complex Services with Multiple QoS Constraints", ICSOC2005
T. Yu and K.J. Lin, " Adaptive algorithms for Finding Replacement Services in Autonomic Distributed Business Processes." ISADS2005
T. Yu and K.J. Lin " A Broker-Based Framework for QoS-Aware Web Service Composition", EEE05
Tao Yu, Yue Zhang, Kwei-Jay Lin: Efficient algorithms for Web services selection with end-to-end QoS constraints. TWEB 1(1): (2007)
今天重读了一遍"Service Selection Algorithms for Web Services with End-to-end QoS Constraints (ISeBM2005)".
本文研究的是如何选择Web服务, 使得组合服务的整体QoS满足约束, 并且使效用值最大.
这篇论文对研究的问题做了一些简化:
(1) 只考虑sequantial composition model (这个是一个比较重大的简化)
(2) 只考虑具有一个QoS约束条件(delay)
使用了两种方式来解决问题: combinatorial approach, graph approach
在combinatorial approach中,
问题被建模为MCKP(多选择背包问题), 并使用了Exhausive search, dynamic programming, Pisinger这3种算法来求解.
这种方式的缺陷是无法对transmision delay和cost进行建模. 由于同一个service class内的不同service可以由不同的provider提供, 而不同的provider可以处于不同的网络, 因此service之间的transmission delay/cost是存在差异的, 但是在combinatorial approach中只能假定两个service之间的transmission delay/cost是一样的.
在graph approach中,
使用DAG进行建模(如果还有其他composition model ,比如parallel, 似乎很难用文中现有的建模方法), 经过转换, 将cost/benefit等参数映射到边上.
将问题建模成图论中的constrained shortest path问题.
使用了Constrained Bellman-Ford(CBF)和Constrained Shortest Path(CSP)算法来求解.
CBF算法是指数级的
其他注意点
(1) dominate relationship (S5.2.3, 算法1中提到)
两条路径a, b, 如果(a.utility >= b.utility) && (a.delay <= b.delay ), 则称路径a dominate 路径b, 即路径a在每一个方面都优于路径b.
(2) topological order
Definition: A numbering of the vertices of a directed acyclic graph such that every edge from a vertex numbered i to a vertex numbered j satisfies i<j.