CSR: Small: Maintaining System Operation in Wireless Sensor Networks Over Long Lifetimes

无线传感器网络技术正被考虑用于许多要求高可靠性和长寿命的真实的世界应用。例如，新的低成本无线传感器网络（WSN）可以嵌入到大城市的摩天大楼中，以支持火灾检测和反应。这种系统必须可靠地检测任何楼层的火灾，启动警报，通知消防站，并宣布和照亮出口路线。这些建筑物被动地监测危险，基本上无人值守。然而，这类系统需要对其运行有高度的信心，并且还必须能够证明它们在定期检查的基础上是可运行的（至少）。该项目确定如何在运行时指定和支持一系列解决方案，使嵌入式系统能够提高可信度并展示应用程序的可操作性。该项目在几个方面都很新颖。首先，它开发了一种需求语言，允许设计人员通过声明性语句、不变量和规则的组合来指定高置信度所需的运行时保证。该语言解决了应用程序语义，WSN的统计性质，成本，对系统性能的未来预测，以及各种机制的监控需求。它还允许自动生成代码。其次，运行时保证方法和框架的开发，支持特定的演示系统？的关键功能，并提供了一个定义良好的诊断能力，包括数据挖掘时，系统无法满足其保证。第三，各种运行时机制的创建和使用的新方法，包括虚拟事件生成和真实的事件重放。第四，作为一个系统的发展，解决方案的理解系统模型应用于控制器的设计。第五，在一个应用领域进行实施和评估。这项工作的广泛影响是可能的，因为在工业工厂，家庭和辅助生活医疗保健和交通中的WSN应用存在类似的问题。一套课程模块的开发，并纳入目前在弗吉尼亚大学的两个课程：无线传感器网络和网络物理系统。相应的教学材料（幻灯片和实验室）可通过网络在其他大学使用。工程学院少数民族事务办公室用于将少数民族学生与本研究相匹配。

Wireless sensor network technology is being considered for many real world applications that require high reliability and long lifetimes. For example, new, low cost wireless sensor networks (WSN) can be embedded into large city skyscrapers to support fire detection and reaction. Such systems must reliably detect a fire on any floor, activate alarms, notify fire stations, and announce and illuminate egress routes. These buildings are passively monitored for hazards and are largely unattended. However, such systems require high confidence in their operation and must also be able to demonstrate that they are operational on a periodic inspection basis (at a minimum). This project determines how to specify and support, at runtime, a collection of solutions that enable embedded systems to improve confidence and demonstrate application operability. The project is novel in several ways. First, it develops a requirements language that permits designers to specify, via a combination of declarative statements, invariants, and rules, the runtime assurances required for high confidence. The language addresses application semantics, the statistical nature of WSN, costs, future predictions on system performance, and monitoring needs for various mechanisms. It also permits automatic code generation. Second, a runtime assurance methodology and framework is developed that supports specific demonstrations of a system?s key functional capabilities on demand and offers a well defined set of diagnosis capabilities including data mining when the system fails to meet its assurances. Third, various runtime mechanisms are created and used in novel ways including virtual event generation and real event replay. Fourth, as a system evolves solutions for understanding the system model as applied to controller design are developed. Fifth, an implementation and evaluation in an application domain is undertaken. Broad impact of the work is possible because similar issues exist for WSN applications in industrial plants, home and assisted living health care, and transportation. A set of course modules is developed and incorporated into two current course offerings at the University of Virginia: Wireless Sensor Networks and Cyber Physical Systems. The corresponding teaching materials (slides and labs) are available for use at other Universities via the Web. The School of Engineering Office of Minority Affairs is used to match minority students with this research.