A Service-Oriented Middleware for Building Collaborative UAVs

For a while, Unmanned Arial Vehicles (UAVs) use was limited to military applications, however recently UAVs are also used for a wide range of civilian applications. Some of these UAV applications may involve multiple UAVs that must cooperate to achieve a common goal. This kind of applications is termed collaborative UAV applications. This paper investigates the collaborative aspects and challenges of multiple UAV systems. One of the main issues for multiple UAV systems is developing an effective framework to enable the development of software systems for collaborative UAV operations. One possible approach is to rely on service-oriented computing and service-oriented middleware technologies to simplify the development and operations of such applications. This paper discusses how the service-oriented middleware approach can help resolve some of the challenges of developing collaborative UAVs. The paper also proposes a service-oriented middleware architecture that can satisfy the development and operations of such applications.     

面向服务的消息中间件研究

将Web服务与消息中间件结合,充分发挥两者的技术优点,提出一种面向服务的消息服务,既提高Web服务的灵活性、可靠性和服务质量,同时又部分解决了Web服务与遗留应用集成的问题.     

Middleware for pervasive computing: A survey

The rapidly emerging area of pervasive computing faces many challenging research issues critical to application developers. Wide heterogeneity of hardware, software, and network resources pose veritable coordination problems and demand thorough knowledge of individual elements and technologies. In order to ease this problem and to aid application developers, different middleware platforms have been proposed by researchers. Though the existing middleware solutions are useful, they themselves have varied features and contribute partially, for context, data, or service management related application developments. There is no single middleware solution that can address a majority of pervasive computing application development issues, due to the diverse underlying challenges. In this survey paper, we identify different design dimensions of pervasive computing middleware and investigate their use in providing various system services. In-depth analysis of the system services have been carried out and middleware systems have been carefully studied. With a view to aid future middleware developers, we also identify some challenging open research issues that have received little or no attention in existing middleware solutions.     

CROWN-C: A High-Assurance Service-Oriented Grid Middleware System

A proposed grid middleware system includes specific enhancements to support the development and assessment of highly secure, dependable, service-oriented grid systems and applications.     

Effectively deploying services on virtualization infrastructure

Virtualization technology provides an opportunity to acieve efficient usage of computing resources. However, the management of services on virtualization infrastructure is still in the preliminary stage. Contstructing user service environments quickly and efficiently remains a challenge. This paper presents a service oriented multiple-VM deployment system (SO-MVDS) for creating and configuring virtual appliances running services on-demand. The system provides a template management model where all the virtual machines are created based on the templates with the software environment pre-prepared. To improve the deployment performance, we explore some strategies for incremental mechanisms and deployment.We also design a service deployment mechanism to dynamically and automatically deploy multiple services within virtual appliances. We evaluate both the deployment time and I/O performance using the proposed incremental mechanism. The experimental results show that the incremental mechanism outperforms the clone one.     

普适环境下基于中间件的身份验证模型*

为了更好地保证普适计算环境中计算资源的安全性,减少人为的非正常破坏,提出了普适环境下应用的身份验证需求,即验证不仅要随时随地,而且可以随着用户的移动在异构设备和计算环境中移动,让移动中的用户能够体验到不间断的计算。提出了基于移动代理的普适计算中间件ValidateAgent,并结合情境感知技术, 给出了验证模型、算法及原理。此研究对于普适计算在协同设计领域中的应用有重要意义。     

An effective offloading middleware for pervasive services on mobile devices

The practical success of pervasive services running in mobile wireless networks and devices relies on their ability to provide effective and efficient offloading support, so as to satisfy the increasing demand for mobile devices to run heavier applications (e.g. those running on desktop PCs). Offloading is an effective mechanism for leveraging the severity of resource constrained mobile devices by migrating some computing load to nearby resource-rich surrogates (e.g. desktop PCs, servers) on home networks or their extension. This paper proposes a light-weight and efficient offloading middleware, which provides runtime offloading services for resource constrained mobile devices. The middleware considers multiple types of resources (i.e. memory, CPU and bandwidth) and carries out application partitioning and partition offloading in an adaptive and efficient manner. The corresponding algorithms are presented. The evaluation outcomes indicate the effectiveness and efficiency of this service offloading solution.     

PerContRep: a practical reputation system for pervasive content services

Social network has extended its popularity from the Internet to mobile domain. Personal mobile devices can be self-organized and communicate with each other for instant social activities at any time and in any places to achieve pervasive social networking (PSN). In such a network, various content information flows. To which extent should mobile users trust it, whilst user privacy can also be preserved? Existing work has not yet seriously considered trust and reputation management, although trust plays an important role in PSN. In this paper, we propose PerContRep, a practical reputation system for pervasive content services that can assist trustworthy content selection and consumption in a pervasive manner. We develop a hybrid trust and reputation management model to evaluate node recommendation trust and content reputation in the context of frequent change of node pseudonyms. Simulations show the advantages of PerContRep in assisting user decisions and its effectiveness with regard to unfair rating attack, collaborative unfair rating attack, on-off attack and conflict behavior attack. A prototype system achieves positive user feedback on its usability and social acceptance.     

一种保证传感器网络实时服务的中间件机制

传感器网络技术的发展导致了在应用与网络之间建立中间件,根据系统资源及网络能源保证在网络上并发运行的应用的QoS。首先,本文结合传感器网络的特性及实时应用的特点,定义了一个事件驱动的保证实时QoS的传感器网络中间件框架。然后,定义了传感器网络中实时应用的执行模型,提出了一种基于时间戳相关的实现技术,在应用调度中结合应用语义保证实时QoS、数据流的时间一致性及并发应用执行的逻辑一致性。最后,给出了基于时间戳模型的调度算法。通过性能测试结果分析表明,它能够显著提高系统的运行效率及对高速外部采集数据处理的实时性,特别适应于处理间歇、高速的传感器网络外部采集数据。     

基于多模态知识感知注意力机制的问答方法

随着网络的普及,越来越多人遇到身体不适时,会选择在网站上搜索相关症状.随着在线医疗问答网站的出现,如春雨医生、寻医问药等,患者可以便捷地医生交流.现有的问答系统方法,聚焦于词级别的交互与语义信息,却很少考虑在回答问题时,回答者还利用了与问答本身无直接联系的常识.在实际生活中,除了病人的表述,医生还需要额外知识来诊断病人.提出了一个基于多模态知识感知注意力机制的医疗问答方法,它可以有效地利用多模态医疗知识图谱来构建基于知识图谱的问答对之间的交互.该模型首先学习知识图谱中实体的多模态表示;然后从多模态知识图谱中与问答对相关联的实体的路径来推测出回答该问题时的逻辑,并刻画问答对之间的交互关系.此外,该模型还提出了一种注意力机制来判别连接问答对的不同路径之间的重要性.构建了一个大规模的多模态医疗知识图谱和一个医疗问答数据集,实验结果表明:该方法比当前最好的方法准确度提升了2%以上.     

一种低成本普适网络环境构建及服务优化研究

蓝牙技术具有低成本、低覆盖范围、高速率和方便组织微微网等特点,ZigBee技术具有低功耗,低复杂性、低成本、长距离组网等特点,构建两者结合的低成本普适网络环境,提出基于用户属性的多用户接入算法和带宽分配算法。硬件体系由ARM、蓝牙、ZigBee、传感器等主要模块构成,软件环境为Linux操作系统。系统运行状态平稳,蓝牙和ZigBee信道利用率高,能够很好地满足用户对数据的下载需求,而且应用多用户接入算法使系统各项指标均好于系统采用平均分配算法。     

Middleware services for P2P computing in wireless grid networks

Advances in network architecture are changing application and service delivery. The wireless industry, for example, now talks of service grids - collections of separate wireless services collated from across the network. However, with current limitations in mobile device capabilities, a scalable and efficient middleware platform is essential. The authors' new middleware architecture, called scalable inter-grid network adaptation layers (signal), integrates mobile devices with existing grid platforms to conduct peer-to-peer operations through proxy-based systems. Combining mobile P2P applications with grid technologies could ultimately give mobile devices the power of supercomputers.     

Providing advanced remote medical treatment services through pervasive environments

Advances on sensor technology, wireless environments and data mining introduce new possibilities in the healthcare sector, realizing the anytime-anywhere access to medical information. Towards this direction, integration of packet-switched networks and sensor devices can be effective in deploying assistive environments, such as home monitoring for elderly or patients. In this paper we describe a policy-based architecture that utilizes wireless sensor devices, advanced network topologies and software agents to enable remote monitoring of patients and elderly people; through the aforementioned technologies we achieve continuous monitoring of a patient’s condition and we can proceed when necessary with proper actions. We also present a software framework and network architecture that realizes the provision of remote medical services, in compliance with the imposed security and privacy requirements. A proof of concept prototype is also deployed, along with an evaluation of the overall architecture’s performance.     

A business model for deploying Web services:A data-centric approach based on factual dependencies

The standards XML, SOAP, WSDL and UDDI allow (i) services to be accessed and executed via the Web; and (ii) a loose coupling of these services. Thanks to these standards, Web services technology is becoming not only a de facto integration standard, but also a de facto Internet standard instance of the SOA architecture. However, the deployment of such a technology is still hindered by some technical as well as methodological issues. This paper proposes a business model with multiple interfaced abstraction levels as a framework to methodologically deploy Web services technology with respect to SOA architecture. The attributes describing the business objects and coordination artifacts as described in the highest abstraction level of the business model, i.e. the universe of discourse, are aggregated according to a time/space constraint called factual dependency. Each aggregation of factually dependent attributes is validated with regard to an actual business event. The aggregation is then interfaced to lead to a well-specified Web service. The resulting comprehensive set of consistent Web services are then registered in a public or a private UDDI to be discovered and invoked by any business process. The proposed Web services generation process aims at unlocking and turning informational assets into actions. It differs from the current IT perspective approaches that generate Web services directly from redundant and inconsistent elements in the enterprise information systems.     

Ontological user modelling and semantic rule-based reasoning for personalisation of Help-On-Demand services in pervasive environments

Existing context-aware applications are limited in their support of user personalisation. Nevertheless, the increase in the use of context-aware technologies has sparked the growth in assistive applications resulting in a need to enable adaptation to reflect the changes in user behaviours. This paper introduces a systematic approach to service personalisation for mobile users in pervasive environments and presents a service-oriented distributed system architecture. The developed approach makes use of semantic technologies for user modelling and personalisation reasoning. In the paper we characterise user behaviours and needs in pervasive environments upon which ontological user models are created with special emphasis being placed on ontological modelling of dynamic and adaptive user profiles. We develop a rule-based personalisation mechanism that exploits semantic web rule mark-up language for rule design and a combination of semantic and rule-based reasoning for personalisation. We use two case studies focusing on providing personalised travel assistance for people using Help-on-Demand services deployed on a smart-phone to contextualise the discussions within the paper. The proposed approach is implemented in a prototype system, which includes Help-on-Demand services, content management services, user models and personalisation mechanisms in addition to application specific rules. Experiments have been designed and conducted to test and evaluate the approach with initial results demonstrating the functionality of the approach.