引汉济渭工程运行调度综合服务平台的应用实践

针对引汉济渭工程运行调度的实际需求和特点,基于云计算技术,采用面向服务的体系结构(SOA)和JAVA EE平台技术架构,研发了基于云服务架构的引汉济渭工程运行调度综合服务平台,建立了基于平台、组件、知识图及可视化工具灵活搭建的引汉济渭工程运行调度业务应用系统构建模式,形成基于平台、基于组件、基于主题、基于可视化的应用模式,解决了传统的工程运行调度系统应用性差、功能单一、可扩展性差及应用模式单一等问题。通过平台提供工程运行调度业务服务,为工程联合调度提供技术支撑。     

Mobile augmented reality based context-aware library management system

Mobile augmented reality has gained popularity in recent years due to the technological advances of smartphones and other mobile devices. One particular area in which mobile augmented reality is being used is library management. However, current mobile augmented reality solutions in this domain are lacking in context-awareness. It has been suggested in the literature that agent programming may be suitable at overcoming this problem, but little research has been conducted using modern mobile augmented reality applications with agents. This paper aims to bridge this gap through the development of an agent-based, mobile augmented reality prototype, titled Libagent. Libagent was subjected to five experiments to determine its suitability, efficiency, and accuracy for library management. The results of these experiments indicate that agent-based mobile augmented reality is a promising tool for context-aware library management.     

Joint routing and location-based service in VANETs

Geographic routing protocols use location information when they need to route packets. In the meantime, location information are maintained by location-based services provided by network nodes in a distributed manner. Routing and location services are very related but are used separately. Therefore, the overhead of the location-based service is not considered when we evaluate the geographic routing overhead. Our aim is to combine routing protocols with location-based services in order to reduce communication establishment latency and routing overhead.     

Multi-tier service differentiation by coordinated learning-based resource provisioning and admission control

Multiple Internet applications are often hosted in one datacenter, sharing underlying virtualized server resources. It is important to provide differentiated treatment to co-hosted applications and to improve overall system performance by efficient use of shared resources. Challenges arise due to multi-tier service architecture, virtualized server infrastructure, and highly dynamic and bursty workloads. We propose a coordinated admission control and adaptive resource provisioning approach for multi-tier service differentiation and performance improvement in a shared virtualized platform. We develop new model-independent reinforcement learning based techniques for virtual machine (VM) auto-configuration and session based admission control. Adaptive VM auto-configuration provides proportional service differentiation between co-located applications and improves application response time simultaneously. Admission control improves session throughput of the applications and minimizes resource wastage due to aborted sessions. A shared reward actualizes coordination between the two learning modules. For system agility and scalability, we integrate the reinforcement learning approach with cascade neural networks. We have implemented the integrated approach in a virtualized blade server system hosting RUBiS benchmark applications. Experimental results demonstrate that the new approach meets differentiation targets accurately and achieves performance improvement of applications at the same time. It reacts to dynamic and bursty workloads in an agile and scalable manner.     

Self-scaling cooperative discovery of service compositions in unstructured P2P networks

We propose an efficient technique for improving the performance of automatic and cooperative compositions in unstructured Peer-to-Peer networks during service discovery. The technique exploits a probabilistic forwarding algorithm that uses different sources of knowledge, such as network density and service grouping, to reduce the amount of messages exchanged in the network. The technique, analysed in several network configurations by using a simulator to observe resolution time, recall and message overhead, presents good performance especially in dense and large-scale service networks.     

一种融合服务满意度的多因素感知云服务性能预测策略

提出了一种多因素感知的云服务性能预测策略,它基于综合权衡服务提供商的利益,通过合理定价和性能保障来量化和优化服务满意度,并以之驱动性能预测,并引入效用理论实现服务满意度的合理定价.最后通过模拟实验表明,它能够降低SLA破坏率,有效提高云服务的资源利用率.     

基于经纬网格的递增KNN位置隐私保护查询算法

为了在使用基于位置的服务时用户的位置信息不被不可信的位置服务提供商所泄漏,k-匿名位置隐私保护已被广泛研究.然而在集中匿名器被黑客控制时原k-匿名算法会泄漏所有用户的位置隐私,在进行k个最近邻目标查询时对网络的负载较重,而SpaceTwist算法又不能保证k-匿名.提出了一种基于经纬网格的递增KNN位置隐私保护查询算法,将经典的k-匿名算法与SpaceTwist算法相杂交,并引入经纬网格代替原来精确的位置上报给集中匿名器,从而解决了上述问题.实验证明基于经纬网格的递增KNN查询算法比较节省从集中匿名器到位置服务提供商的服务器之间的网络流量.     

ACE中设计模式在分布式网络服务中的应用研究

以网关应用服务的构建为例,详细探讨如何利用Acceptor-Connector模式来构建分布式网络服务的过程。通过分析其构造过程可知,利用Acceptor-Connector模式可提高程序的灵活性、可扩展性,减少重复开发代码工作量。     

Web服务质量建模及其正确性验证

针对现有的Web服务质量模型主要考虑的都是通用的服务质量属性,没有考虑特定的Web服务属性在评价中的作用,提出了一个新的Web服务质量模型,它引入了一个特定领域的服务质量属性,该模型包括三个子模型。模型中建立了相关的服务质量树和目标对象树,通过量化指标子模型对目标对象进行量化,形成相应的服务权重树。该模型既可适应用于单个的Web服务请求,也可以用于多个服务组合而成的请求。通过一个应用实例验证了模型的正确性和可用性。     

JSP嵌套SQL Server Reporting Services报表

针对传统物流行业报表的制作、呈现、管理都是由报表业务人员进行操作,不能及时的将报表呈现的数据信息反馈给决策者,导致信息的延误。通过对JSP以及SQL Server Reporting Service（SSRS）的分析介绍,提出把SSRS报表嵌套在JSP中,加入到网络物流系统操作平台。基于SQL Server 2008 R2数据库以及Spring MVC框架,运用Spring注解方式与JSP技术进行系统开发,直接将SSRS报表嵌套在JSP页面供决策者分析。结果表明,JSP页面可以嵌套带有参数要求的SSRS报表,并且可以准确的读取操作SSRS报表,获得满意的嵌套效果。