Call for Papers: Special Issue on Model-Driven System-Performance Engineering for CPS

I’m honored to serve as Guest Editor for a special issue of IET Cyber-Physical Systems: Theory and Applications focused on Model-Driven System-Performance Engineering for CPS. This issue is a collaboration with Twan Basten (Eindhoven University of Technology), Arvind Easwaran (Nanyang Technological University), and Marilyn Wolf (University of Nebraska-Lincoln).

We invite submissions from both academia and industry across various application domains. If you’re working in this area, consider contributing your research! The submission deadline is November 1, 2024. Feel free to reach out if you have any questions!


Model-Driven System-Performance Engineering for CPS

Submission deadline: Friday, 1 November 2024
Expected Publication Month: June 2025

System performance refers to the amount of useful work done by a system within predefined quality constraints. System performance often brings the competitive advantage for cyber-physical systems in domains like autonomous driving, chip manufacturing and production systems in general, healthcare, the smart grid, precision agriculture, and so on. To meet market demands for product and system quality, system customization, and a low total cost of ownership, systems need to meet ever more ambitious targets relating to system performance. Performance is a cross-cutting system-level concern, with intricate relations to other system-level concerns like quality, cost, energy efficiency, security, reliability, and customizability. Model-driven system-performance engineering (MD-SysPE) for CPS is essential to improve time-to-quality and the cost-performance ratio of complex systems.

This special issue invites any contributions in model-driven system-performance engineering for CPS that are of interest to the academic and industrial CPS community at large. Original research papers, industrial applications and case studies, and surveys on relevant topics are welcome.

Topics for this call for papers include but are not restricted to:

  • Multi-domain modelling, analysis, and optimization of performance aspects
  • Performance views in system architecture
  • Modelling and analysis of trade-offs with other system qualities
  • Modelling and analysis across abstraction levels
  • Design-space exploration methods
  • Synthesis methods targeting performance
  • Scheduling, control in relation to performance
  • Time-predictable (software) execution
  • Data-driven performance analysis and optimization
  • AI methods for performance analysis, optimization, diagnostics
  • Performance monitoring
  • Run-time adaptation and optimization
  • Performance debugging and diagnostics
  • Model learning for performance
  • Performance validation, verification, and testing

TNO-ESI and Academic Partners Deliver ASCI PhD Course on Design and Implementation of Real-time Systems

The Netherlands boasts a world-leading high-tech manufacturing industry renowned for constructing distributed real-time systems of continuously growing complexity. These systems must meet stringent timing requirements to ensure the delivery of mission-critical functionalities. To create interest in the high-tech equipment domain and prepare PhD students in Computer Science to address its performance challenges, TNO-ESI has co-created and delivered a one-week PhD course Design and Implementation of Real-time Systems together with academic partners from Eindhoven University of Technology, University of Twente, and University of Amsterdam. The course is given in the context of the Advanced School for Computing and Imaging (ASCI), a Dutch research school for high-quality research and education in computer systems and imaging systems. ASCI encompasses almost all Dutch universities with computer-science departments. The main goals of ESI involvement in this course were to make participants aware of TNO and its role in society and industry and position it as a possible future employer, and creating awareness of TNO-ESIs vision and work in the area of system performance engineering.

The course is focused on providing an overview of selected timing-sensitive applications and the current research landscape on real-time systems and explaining the rationale behind considering real-time requirements in system software design. Through a series of lectures and hands-on labs, the course covers selected topics from scheduling algorithms, priority assignments, resource sharing, resource reservation, together with their implementation in real-time operating systems. It further discusses emerging challenges and practices in an industrial context, based on empirical surveys and experience from TNO-ESIs applied research on telemetry-based system performance engineering for purposes of performance optimization, verification, and diagnostics.

This first instance of the course was given at the Carlton President Hotel in Maarsen, outside Utrecht between June 10 – 14. 15 PhD students from universities all over the Netherlands researching a broad range of topics in computer science participated in the course. TNO-ESI was in the spotlight during the last day of the course. In the morning, I introduced the high-tech equipment domain and its complexity drivers and explained how new model-based engineering methodologies where needed to address them. Next, my colleague Bram van der Sanden presented our view on the field of System Performance Engineering, along with its focus areas and best practices. This was followed by two concrete examples from our system performance research: Kostas Triantafyllidis presented his work on performance analysis and diagnosis with ASML, followed by a presentation by me about performance verification and conformance checking in microservice systems based on our work with Thales.

The course was well-received by the participants and the contents were rated 8.7/10 in the evaluation. We very much enjoyed the experience of creating and delivering this course together with our academic partners. Thank you Kuan-Hsun Chen (leader of the initiative), Mitra Nasri, and Geoffrey Nelissen for the excellent collaboration in organizing this course. Thanks to Kay Heider and Christian Hakert for leading the hands-on exercises. We are also thankful to invited speakers Bram van der Sanden and Kostas Triantafyllidis.

Inaugural Lecture Explores Managing Complexity of High-Tech Systems

Today, I finally gave my inaugural lecture “Managing Complexity in High-tech Systems” to celebrate my appointment as Endowed Professor at the University of Amsterdam, which happened back in 2019.

The academic ceremony started at 16:00 with a small reception for fellow professors and members of the curatorium. Together, this group walked in a procession into the beautiful auditorium of the University of Amsterdam, where an audience of colleagues, family, and friends, where waiting in anticipation. The lecture discussed the challenge of increasing complexity in the high-tech equipment industry and how new (model-based) development methodologies leveraging abstraction, boundedness, and composition, are required to address it. I argued that the required innovation should come from collaboration in an innovation chain, where universities, applied research organizations, and industry work together in strategic partnerships. The presentation was concluded with a number of concrete examples of what this collaboration could look like, based on examples from my education and research at TNO and the University of Amsterdam. The inaugural lecture was followed by a reception full of networking and congratulations. I would like to thank everybody that showed up for the event, physically and online. Together, we created a memory that I will treasure for a lifetime.

If you did not manage to attend the lecture, or see it online, there is a recording available. Pop some popcorn, take a seat, and click the link below:

https://webcolleges.uva.nl/Mediasite/Play/99497b81432a49acb57f0ae7a32050d11d

Master Thesis on Formal Verification of Software Interfaces Defended

Today, Bart-Jan Hilbrands, a master student from UvA supervised by myself and my ESI colleague Debjyoti Bera, successfully defended his master thesis “Verification of Inter-Dependent Interfaces in Component-Based Architectures”. The thesis considers formal verification of ComMA components with multiple interfaces with inter-dependent behavior, caused by three different types of functional constraints. The four main contributions of the thesis are: 1) A formalization of each type of interface constraint, defining how they should restrict behavior, 2)  a set of assumptions, describing properties that help ComMA users avoid creating specifications with termination issues, 3) methods for encoding the behavior of these constraints into existing Petri net representations of interfaces, and 4) methods for validating whether a set of given constraints is encoded correctly into a given Petri net. The theory is supported by a prototype implementation ComMA.

Bart presented his thesis well and expertly answered questions from the committee. We thank Bart for his excellent work and wish him good luck is his future career. First off, he will continue working with me and Deb to publish his work as a paper.

Paper about Model-driven System Performance Engineering Accepted at ESWEEK Industry Session

The System Performance Expertise Team at ESI (TNO) has worked for a long time to consolidate our many years of experience across projects and companies. This effort has now culminated in a paper entitled “Model-driven System Performance Engineering for Cyber-physical Systems“, which has been accepted for the industry session at the Embedded Systems Week (ESWEEK) in October.

The paper describes ESI’s current view on the field of System-Performance Engineering (SysPE). SysPE encompasses modeling formalisms, methods, techniques, and industrial practices to design systems for performance, where performance is taken integrally into account during the whole system life cycle. Industrial SysPE state of practice is generally model-based. Due to the rapidly increasing complexity of systems, there is a need to develop and establish model-driven methods and techniques. To structure the field of SysPE, the paper identifies: (1) industrial challenges motivating the importance of SysPE, (2) scientific challenges that need to be addressed to establish model-driven SysPE, (3) important focus areas for SysPE and (4) best practices. A survey was conducted to collect feedback on our views. The responses were used to update and validate the identified challenges, focus areas, and best practices. The final result is presented in this paper. Interesting observations are that industry sees a need for better design-space exploration support, more than for additional performance modeling and analysis techniques. Also tools and integral methods for SysPE need attention. From the identified focus areas, scheduling and supervisory control is seen as lacking established best practices.

The paper will be presented as a part of Industry Session 2 at ESWEEK on October 12. The second talk of that session presents why and how ITEC, Nexperia, a world-leading manufacturer of semiconductor equipment, is moving towards model-driven system-level development. The session ends with a moderated Q&A. Since ESWEEK is an online event this year, you can register for 20 USD if you want to attend the conference and the session.

Update: The video of the Industry session is now available:

ESI Featured in Nederland Maakt Het

ESI (TNO) was featured in the latest episode (Season 4 Episode 1) of Nederland Maakt Het, a program on RTL Z about Dutch organizations that develop of apply innovative technologies. In the segment, Wouter Leibbrandt, the Research and Operations director at ESI, explains that the Netherlands has a powerful high-tech industry, which is important to its competitiveness and earning power. To stay at the top and continue to develop excellent products in light of increasing system complexity, it is important to invest in research and development of new design methodologies. Big high-tech companies do this in an open innovation environment to address the challenges they face together. ESI is the applied research organization and knowledge partner that brings the industry and academic parties together into an eco-system to facilitate this.

In my role as part-time professor at UvA, I explain my view on open innovation and how universities contribute and get value from the eco-system. In the Embedded Software and Systems course at the University of Amsterdam, which is an academic partner of ESI since 2021, I discuss the increasing system complexity with my students and teach model-based engineering methodologies to help them address this challenge. I also supervise students that want to contribute to solving the complexity problem by doing their thesis project in with ESI or in industry.  Lastly, Hein Otto Folkerts, the (former) head of Research at ASML, provides the industry view and explains the value of open innovation to ASML, one of the big high-tech companies in the Eindhoven region.

For those of you that missed the episode, it is available for online viewing on RTL XL. The segment about ESI starts at 14m30s and last for about 4 minutes. ESI also has a version of this segment in its own house style that is used for promotional purposes. This version is available here:

Embedded Software and Systems Course @ UvA Continues to Evolve

The fall semester of the very special academic year 2020/2021 is over. Most of the students following the Master of Software Engineering program at the University of Amsterdam have just completed my course Embedded Software and Systems (ESS). The ESS course had changed in a three important ways this year.

Firstly, a generic lecture about Petri Nets was changed to a series about two lectures, explaining how Petri Nets can be used to model and analyze software interfaces and components. Part of the material for this course was reused from the course Modelling and Analysis of Component-based Systems (MOANA-CBS), developed together with Thales targeting an industrial audience. These new lectures also prime students nicely for a lecture about the DYNAMICS project, a research collaboration between ESI and Thales. This allows me to show how these models and analyses can be used in practice to address problems related to software evolution by detecting incompatibilities and generating adapters when updating software interfaces. A generic lecture about the data-flow model of computation was removed to create room for this new material, but I am happy to teach fewer modelling formalisms and have more time to go in depth and show how they can be used to solve industrial problems. A nice result of this change to the course is that three master students have accepted thesis projects in the area of modelling and analysis of software components and interfaces in collaboration with ESI under the supervision of myself and my colleague Debjyoti Bera.

Secondly, the course project was redeveloped this year. Previously, students used Mathworks Stateflow to program Lego Mindstorm EV3 rovers to follow a line, avoid obstacles, and count objects. However, this project felt a bit too much like a toy and there were technical problems with both rovers and tools that were hard to overcome and limited the education experience. In particular, it was not easily possible to see or influence how code was generated for the Lego Mindstorm robots, which felt like a missed opportunity when teaching model-based engineering. 

Two bachelor students did their theses in spring to evaluate the suitability of using the TurtleBot3 Burger robot, both in reality and in simulation using Gazebo, in the course. In addition, Stateflow was exchanged for Yakindu Statechart Tools, which is easier to use and gives us the flexibility we need in code generation. The new application developed in the project is to use Yakindu to program the TurtleBot to autonomously drive through a maze and map it.

Lastly, the COVID-19 pandemic required the entire course to be taught online. As a result, used a blended learning approach and prerecorded the lectures so that the students could watch them when they wanted to. Online interactive sessions were added to the course where the students could ask questions about the lectures, and participate in quizzes and group discussions. Online teaching meant that the students did not have access to the four physical TurtleBots that we had purchased. Luckily, the newly developed course project could be done with simulations in Gazebo. Below is a demo from one of the groups that very successfully solved the assignment. 

The ESS course is continuously evolving and maturing and next year will be no different. Most importantly, we hope that the pandemic will be over by then and that we can put our three physical TurtleBots to good use.

Model-based Engineering Dominates Software-Centric Systems Conference

I attended the online edition of Software-Centric Systems Conference (SC2) today. Although I prefer the networking and social aspects of a physical conference, it was nice to enjoy these presentations from the comfort of my couch.

It was interesting to see that most of the conference presentations were related to domain-specific languages (DSLs) in one way or another. There were also presentations about model-based testing and digital twinning. I am not sure if model-based engineering was an intentional theme, or if this is just what is considered interesting in software-centric systems in the Netherlands for the moment. However, this suggests that the applied research into model-based design methodologies done by ESI (TNO) together with its industrial eco-system is highly relevant.

A highlight for myself was the two presentations about the Component Modelling and Analysis (ComMA) DSL. This is not only because it relates to my research on evolvable interfaces, but also because of the main message that the industry can achieve a lot through open innovation in areas that are not their core business, such as specification, verification, and evolution of software interfaces. Great news that ComMA will become open-source in 2021!

Design Methodologies for Cyber-physical Systems

In this short two minute presentation, I introduce myself and my fundamental and academic research into design methodologies for cyber-physical systems. I sketch a high-level view of the problem and outline a direction based on model-based engineering in which my previous work into domain-specific languages and analysis non-functional behavior fits. For a more elaborate description of my research, please have a look at my research page.

Paper Accepted at GPCE 2020

A paper entitled “PReGO: a Generative Methodology for Satisfying Real-Time Requirements on COTS-based Systems – Definition and Experience Report” was accepted for publication at the 19th International Conference on Generative Programming: Concepts & Experiences (GPCE). This is my first paper in collaboration with my new colleagues at the University of Amsterdam, and it describes work done in the TeamPlay project, a three-year research project funded by the EU Horizon 2020 research and innovation programme.

The paper addresses the problem of satisfying real-time requirements in industrial systems using unpredictable hardware and software, which limit or entirely prevent the application of established real-time analysis techniques. To this end, we propose PReGO, a generative methodology for satisfying real-time requirements in industrial commercial-off-the-shelf (COTS) systems. We report on our experience in applying PReGO to a use-case: a Search & Rescue application running on a fixed-wing drone with COTS components, including an NVIDIA Jetson board and a stock Ubuntu/Linux. We empirically evaluate the impact of each integration step and demonstrate the effectiveness of our methodology in meeting real-time application requirements in terms of deadline misses and energy consumption.