Hasso-Plattner-Institut
Prof. Dr. Holger Giese
  
 

Dr. Leen Lambers

Senior Researcher

 

Phone: +49 (0)331 5509 352

E-Mail: Leen.Lambers(at)hpi.de

Room: A-E.8

Research topics

As part of digitalization, more and more functionality of systems is realized through software.  Areas that were previously decoupled are now interlinked using various types of software.  Examples include web and mobile applications with social network integration, learning bots, services for managing business processes, up to embedded software in self-driving vehicles and production systems in Industry 4.0.

Quality assurance (QA) for software & systems in the era of digitalization therefore requires a comprehensive approach.  A tight integration of flexibly transformable and incrementally verifiable models into the development process enables us to manage with a clear commitment to quality the rising complexity and heterogeneity of today's data- and software-intensive systems with increasing adaptivity requirements.  Our approach to quality assurance is therefore based on the integration of the following research areas:  

  • model engineering: for the construction of models for systems
  • transformation engineering: for the construction of automatic (from deterministic to search-based and randomized) methods for the transformation of systems
  • verification engineering: for the construction of techniques (analysis, test, formal verification) that support quality assurance in the entire life cycle of systems.

Since the underlying structure of models can be described very well by graphs, graph transformation is a suitable means to specify model transformations. In addition, graph transformation also lends itself to the management and evolution of semi-structured data. We therefore use graph and graph transformation theory as a solid pioneer for the interaction of the above-mentioned research fields. In this focus, we develop the following foundations:

  • graph logic: automated reasoning and sat solving for graph properties, automated graph repair
  • graph transformation: analysis, test, formal verification
  • category theory for transformation systems: consolidation and unification of transformation theory for different variants of high-level structures such as typed graphs, labeled graphs, triple graphs, hypergraphs, Petri nets, attributed graphs, algebraic specifications, etc.

Based on these foundations, we continuously strive to develop and implement QA techniques that take into account basic engineering principles such as expressiveness, efficiency, usability, and are generally applicable.  The overall goal is to create QA techniques that are closely linked to the software development process and include an appropriate level of automation and human interaction. Selected examples of QA techniques that we are researching are the following:

  • conflict and dependency detection in requirement specifications
  • plausibility checking of executable models
  • consistency and behavior preservation (resp. functional behavior) verification for model transformations (or model refactorings in particular)
  • conformance testing of triple graph grammar implementations
  • model-based testing of graph databases & graph database applications.

Our QA techniques can be used in different domains and applications. We apply them, for example, for quality assurance of:

  • adaptable service-based applications, such as a personal mobility manager
  • refactorings, e.g. of finite automata, state charts, or JAVA programs
  • modernizations of legacy systems
  • model synchronization, e.g. for the model-based development of automotive systems and flexible production systems
  • query implementations in social network applications.

Finally, we investigate and support concepts and international initiatives for dissemination, training, and further education in "Quality assurance in software & systems engineering". 

Teaching

Scientific Events

  • PC member ICGT 2021 14th International Conference on Graph Transformation
  • PC member GCM 2021 12th International Workshop on Graph Computation Models
  • PC chair Bx 2021 9th International Workshop on Bidirectional Transformations
  • PC member FASE 2021 24th International Conference on Fundamental Approaches to Software Engineering
  • Scientific committee member GreTA: International (Virtual) Seminar Series on Graph Transformation Theory and Applications
  • PC member MoDeVVa 2020 17th Workshop on Model-Driven Engineering, Verification and Validation
  • PC member ME 2020 14th International Workshop on Models and Evolution
  • Member selection committee MODELS20-Demo Tools and Demonstrations at 23rd International Conference on Model Driven Engineering Languages and Systems
  • PC member EduSymp@Models2020
  • PC chair Bx 2020 9th International Workshop on Bidirectional Transformation (postponed to 2021)
  • PC member WADT 2020 25th International Workshop on Algebraic Development Techniques
  • PC member ICGT 2020 13th International Conference on Graph Transformation
  • PC member ME 2019 13th International Workshop on Models and Evolution
  • PC member EduSymp@Models2019
  • PC member MoDeVVa 2019 16th Workshop on Model-Driven Engineering, Verification and Validation
  • PC member GCM 2019 10th International Workshop on Graph Computation Models
  • PC member ICGT 2019 12th International Conference on Graph Transformation
  • PC member ICMT 2019 12th International Conference on Model Transformation
  • PC member BX 2019 8th International Workshop on Bidirectional Transformations
  • PC member ME 2018 Models and Evolution Workshop
  • PC member MoDeVVa 2018 15th Workshop on Model-Driven Enginnering, Verification and Validation
  • PC chair ICGT 2018 11th International Conference on Graph Transformation
  • PC member ICMT 2018 11th International Conference on Model Transformation
  • PC member MoDeVVa 2017 14th Workshop on Model-Driven Engineering, Verification and Validation
  • PC member GAM 2017 3rd International Workshop on Graphs as Models
  • PC member ICGT 2017 10th International Conference on Graph Transformation
  • Publication Chair STAF 2017 Software Technologies: Applications and Foundations
  • PC member MoDeVVa 2016 13th Workshop on Model-Driven Engineering, Verification and Validation
  • PC member VOLT 2016 5th Workshop on the Verificaton of Model Transformation
  • PC member GaM 2016 2nd International Workshop on Graphs as Models 
  • PC member ICGT 2016 9th International Conference on Graph Transformation
  • Participant  Verification of Evolving Graph Structures Dagstuhl Seminar 2015
  • PC member MoDeVVa 2015 12th Workshop on Model-Driven Engineering, Verification and Validation
  • PC member VOLT 2015 4th International Workshop on the Verification of modeL Transformation
  • PC member ICGT 2015 8th International Conference on Graph Transformation
  • PC member VOLT 2014 3rd International Workshop on the Verification Of modeL Transformation
  • PC member ICSME 2014 30th International Conference on Software Maintenance and Evolution
  • PC member & publicity chair ICGT 2014 7th International Conference on Graph Transformation
  • PC member ICSM 2013 29th IEEE International Conference on Software Maintenance
  • OC member VOLT 2013 2nd International Workshop on the Verification of ModeL Transformation
  • PC member ICMT 2013 6th International Conference on Model Transformation
  • PC member ICGT 2012 6th International Conference on Graph Transformation - Foundations Track
  • PC member ICMT 2012 5th International Conference on Model Transformation
  • 2012 Bellairs CAMPaM Workshop on Computer Automated Multi-Paradigm Modeling
  • PC chair GT-VMT 2012 11th International Workshop on Graph Transformation and Visual Modeling Techniques, co-located with ETAPS 2012
  • PC member ACCAT 2012 7th Workshop on Applied and Computational Category Theory, co-located with ETAPS 2012

Publications