A type-centric framework for specifying heterogeneous, large-scale, component-oriented, architectures

Maintaining integrity and consistency, and effecting conformance in architectures of large-scale systems require specification and enforcement of many different forms of structural constraints. While type systems have proved effective for enforcing structural constraints in programs and data structures, most architectural modeling frameworks include only weak notions of typing or rely on first order logic constraint languages that have steep learning curves associated with them and that become unwieldy when scaling to large systems.We present the Cadena Architecture Language with Meta-modeling (CALM) — that uses multi-level type systems to specify and enforce a variety of architectural constraints relevant to the development of large-scale component-based systems. Cadena is a robust and extensible tool that has been used to specify a number of industrial strength component models and applied in multiple industrial research projects on model-driven development and software product lines.     

一种融合多种定位精度改进策略的实时定位中间件

无论是普适计算还是物联网,实时定位均是其关键技术之一。在建筑物、洞室等复杂环境中,由于无线信号的不规则衰减、非视距传播,使得常用的一些定位算法(如接收信号强度、到达角度等)无法达到较高的定位精度。为了解决复杂环境中定位精度不足的问题,设计并实现了一个定位精度改进中间件。它集成了平滑、传感器融合、卡尔曼滤波、粒子滤波等多种精度改进策略,可以根据用户对定位精度的需求动态地选择相应的策略。通过实验分析了不同精度改进策略的性能,结果表明,该中间件能够较好地满足用户对不同精度的需求。     

RFID室内实时定位系统的数据滤波方法

在射频识别室内实时定位应用中,由于场景的复杂性和定位系统的精度有限,定位系统报告的物品的连续两个位置可能出现在不同的区域内,物品的运动轨迹可能出现穿过墙壁等异常。为此,提出了一种避免这种异常的室内定位系统的数据滤波方法。首先,将场景离散化为一幅“灰度图像”,图像像素表示场景中的点,图像像素的灰度表示不同的区域/房间、墙壁或房门;在定位过程中,将物品的连续两个场景坐标分别映射到两个图像像素,利用连接这两个像素的线段上的像素的“灰度”来判断是否出现穿墙等异常,并修正物品当前在图像上的位置;最后,将图像中的位置映射回场景坐标。实验表明,所提方法快速且高效,能有效避免物品运动轨迹中的异常。     

Admission control for a responsive distributed middleware using decision trees to model run-time parameters

The software in modern systems has become too complex to make accurate predictions about their performance under different configurations. Real-time or even responsiveness requirements cannot be met because it is not possible to perform admission control for new or changing tasks if we cannot tell how their execution affects the other tasks already running. Previously, we proposed a resource-allocation middleware that manages the execution of tasks in a complex distributed system with real-time requirements. The middleware behavior can be modeled depending on the configuration of the tasks running, so that the performance of any given configuration can be calculated. This makes it possible to have admission control in such a system, but the model requires knowledge of run-time parameters. We propose the utilization of machine-learning algorithms to obtain the model parameters, and be able to predict the system performance under any configuration, so that we can provide a full admission control mechanism for complex software systems. In this paper, we present such an admission control mechanism, we measure its accuracy in estimating the parameters of the model, and we evaluate its performance to determine its suitability for a real-time or responsive system.     

一个利用EMAIL实现分布数据共享的方法

文章介绍一种利用Email实现分布数据共享的方法。文中先对该方法的几个要点进行了描述,之后介绍了该方法的设计和实现过程,最后介绍了它在好来西CIMS系统中的应用。     

Software Architectures for Reducing Priority Inversion and Non-determinism in Real-time Object Request Brokers

There is increasing demand to extend Object RequestBroker (ORB) middleware to support distributed applications withstringent real-time requirements. However, conventional ORB implementations,such as CORBA ORBs, exhibit substantial priority inversion andnon-determinism, which makes them unsuitable for applicationswith deterministic real-time requirements. This paper providestwo contributions to the study and design of real-time ORB middleware.First, it illustrates empirically why conventional ORBs do notyet support real-time quality of service. Second, it evaluatesconnection and concurrency software architectures to identifystrategies that reduce priority inversion and non-determinismin real-time CORBA ORBs. The results presented in this paperdemonstrate the feasibility of using standard OO middleware likeCORBA to support certain types of real-time applications overthe Internet.     

中间件的优先队列技术研究

在三层体系结构（客户端－中间件－服务器端）中,中间件作为客户端和服务端的中间层,起到至关重要的作用,优先队列是指在中间件的应用程序需要处理多个任务时,按任务的轻重顺序执行,使用户的平均等待时间最短,本文讨论了用二叉堆算法实现优先队列。     

一种灵活的RFID事件规则管理框架*

射频识别（Radio Frequency Identification,RFID）技术的快速发展,使RFID中间件已经成为业界关注的焦点。初步探讨了RFID中间件中事件规则管理的内容,并提出一种灵活的RFID事件规则管理框架,全面介绍了RFID事件编码、模式过滤、目标事件识别以及业务规则定义四个环节的内容,重点阐述了一种基于XML语言的业务规则定义方法及其执行引擎的底层实现,从而为构建更加具有个性化和扩展能力的RFID应用奠定了基础。     

基于CORBA的CRM开发

随着软件技术和信息技术的发展,CRM逐渐成为企业应用的焦点。以CORBA中间件技术为依托,给出了基于CORBA的CRM应用系统软件架构,并给出了具体的开发流程以及主要难点的解决方案。