PRECISE Engineers Receive Awards at CPSWeek 2012
Cyber-Physical Systems Week, or "CPSWeek," brings together five leading conferences as well as several workshops and tutorials on various aspects on the research and development of cyber-physical systems: embedded systems, hybrid systems, real-time systems and sensor networks. At CPSWeek 2012 in Beijing, the Penn Research in Embedded Computing and Integrated Systems Engineering (PRECISE) Center won best paper awards in two conferences.
Conferences included in the events are the Hybrid Systems: Computation and Control (HSCC) conference; the International Conference on Cyber-Physical Systems (ICCPS); the conference on Information Processing in Sensor Networks (IPSN); the Real-Time and Embedded Technology and Applications Symposium (RTAS); and the conference on High Confidence Networked Systems (HiCoNS).
The Best Paper Award for the 2012 HSCC conference went to the paper entitled, "Optimal Scheduling for Constant-Rate Multi-Mode System" authored by Rajeev Alur, Zisman Family Professor in Computer and Information Science (CIS), Ashutosh Trivedi, postdoctoral fellow in CIS, and Dominik Wojtczak, a postdoctoral fellow in Computer Science at the University of Oxford.
Abstract: Constant-rate multi-mode systems are hybrid systems that can switch freely among a finite set of modes, and whose dynamics is specified by a finite number of real-valued variables with mode-dependent constant rates. The schedulability problem for such systems is to design a mode-switching policy that maintains the state within a specified safety set. The main result of the paper is that schedulability can be decided in polynomial time. We also generalize our result to optimal schedulability problems with average cost and reachability cost objectives. Polynomial-time scheduling algorithms make this class an appealing formal model for design of energy-optimal policies. The key to tractability is that the only constraints on when a scheduler can switch the mode are specified by global objectives. Adding local constraints by associating either invariants with modes, or guards with mode switches, lead to undecidability, and requiring the scheduler to make decisions only at multiples of a given sampling rate, leads to a PSPACE-complete schedulability problem.
The Best Student Paper Award for RTAS 2012 went to Miroslav Pajic, a doctoral student in Electrical and Systems Engineering (ESE), for his paper entitled, "From Verification to Implementation: A Model Translation Tool and a Pacemaker Case Study," authored by Pajic, Zhihao Jiang, a doctoral student in CIS, Insup Lee, Cecilia Fitler Moore Professor in CIS, Oleg Sokolsky, Research Associate Professor in CIS, and Rahul Mangharam, Stephen J. Angello Term Assistant Professor in ESE.
Abstract: Between 1990-2000, over 600,000 implantable medical devices were recalled. Over 40% of these were recalled due to software issues. The Food and Drug Administration (FDA) which approves such devices currently does not look at the software in the devices. Implantable medical devices such as Cardiac Pacemakers cost between $22,000 - $35,000 and, more importantly, contain between 80,000-100,000 lines of code. The goal of this project is to develop safe and bug-free software for life-critical medical devices. In this paper, a toolchain has been developed to allow verified software designs to be seamlessly translated into safe code so the patient's life is never at risk due to malfunctioning device software. This effort is a step in the direction of developing a more systematic and efficient device certification process for future medical devices.
Conferences for CPSWeek 2013 will take place in Philadelphia and will be hosted by the PRECISE Center.