Sehr geehrte Damen und Herren,
aufgrund einer akuten Erkrankung von Herrn Dr. Bossek kann das für morgen angesetzte Oberseminar leider nicht stattfinden.
Wir bedauern diese kurzfristige Absage und werden versuchen, zeitnah einen neuen Termin zu finden.
Mit freundlichen Grüßen
Im Auftrag
Andrea Gibbels
--
Andrea Gibbels, M.A.
Administrative Assistant
Chair for AI Methodology / Lehrstuhl für Methodik der Künstlichen Intelligenz
RWTH Aachen University
E-mail: secret(a)aim.rwth-aachen.de
Phone: +49 241 80 21452
Theaterstr. 35-39
52062 Aachen
Germany
+**********************************************************************
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*
* Einladung
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*
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* Informatik-Oberseminar
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*
*
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Zeit: Mittwoch, 24. Mai 2023, 13.00 Uhr
Ort: Raum 9222, Gebäude E3, Ahornstr. 55
Referent: Dr. Jakob Bossek
Lehrstuhl Informatik 14
Thema: Tailored Evolutionary Operators for the Multi-Objective Spanning Tree Problem
Abstract:
With this talk I want to introduce myself to the RWTH computer science department.
In the first part I will go into detail on paper recently accepted in the evolutionary computation journal (Bossek & Grimme, 2023) entitled “Tailored Evolutionary Operators for the Multi-Objective Spanning Tree Problem”. The second part will give a broader overview of my research foci and projects in the fields of Evolutionary Optimisation and Automated Artificial Intelligence.
The Minimum Spanning Tree (MST) problem is the challenge of finding a tree in an edge-weighted graph that maintains connectivity of all nodes and has minimal costs among all such trees. The MST problem is a fundamental combinatorial optimisation problem with countless applications, e.g., in the construction of communication networks, medical imaging, or many other areas that range from logistic via graph drawing to power grid network design. The basic single-objective version of the MST problem can be solved efficiently, i.e., in polynomial time, e.g., by Prim’s algorithm. The multi-objective MST (moMST) version though (i.e., multiple weights per edge) is NP-hard and suffers from intractability. Thus, efficient heuristics are needed to approximate the set of optimal trade-off solutions.
Evolutionary Algorithms are randomised search heuristics that are among the most successful when it comes to solving NP-hard multi-objective optimisation problems.
I will present recent work on the design of several highly biased sub-graph-based mutation operators for the moMST problem. In a nutshell, these operators replace (un)connected sub-trees of candidate solutions with locally (Pareto-)optimal sub-trees. The latter (biased) step is realised by applying Kruskal’s single-objective MST algorithm to a weighted sum scalarisation of a sub-graph.
I will detail some runtime complexity results for the introduced operators and demonstrate results that show that the sub-graph based operators beat baseline algorithms from the literature even with severely restricted computational budget in terms of function evaluations on four different classes of complete graphs.
Es laden ein: die Dozentinnen und Dozenten der Informatik
Dear all,
We'd like to announce our next AI colloquium which will take place on 25 May 2023, 4-6pm.
Jens Kober, TU Delft, will present on "Robots Learning Through Interaction" (in English) in SuperC/Generali-Saal from 4-5pm. The talk will be held in person but also live streamed via Zoom. The event is free, but a registration is required, and the link can be found on our web page<https://www.ai.rwth-aachen.de/go/id/baofsc>.
After the talk, there will be a networking session in the foyer with drinks and nibbles and all are welcome to stay.
[cid:image002.png@01D9874E.DB9193D0]
We kindly ask you to distribute this among your groups and students. Please feel free to use the attached slide.
Thank you in advance.
Julia Mann (part of the organising team)
Dr Julia Mann
Managing Director
______________________________________________
Center for Artificial Intelligence
RWTH Aachen University
Mies-van-der-Rohe-Strasse 15 office: 123
DE-52074 Aachen phone: +49-241-80 20757
Germany
http://www.ai.rwth-aachen.de<http://www.ai.rwth-aachen.de/>
[cid:image001.png@01D9872C.13EB5180]
+**********************************************************************
*
*
* Einladung
*
*
*
* Informatik-Oberseminar
*
*
*
+**********************************************************************
Zeit: Mittwoch, 24. Mai 2023, 13.00 Uhr
Ort: Raum 9222, Gebäude E3, Ahornstr. 55
Referent: Dr. Jakob Bossek
Lehrstuhl Informatik 14
Thema: Tailored Evolutionary Operators for the Multi-Objective Spanning Tree Problem
Abstract:
With this talk I want to introduce myself to the RWTH computer science department.
In the first part I will go into detail on paper recently accepted in the evolutionary computation journal (Bossek & Grimme, 2023) entitled “Tailored Evolutionary Operators for the Multi-Objective Spanning Tree Problem”. The second part will give a broader overview of my research foci and projects in the fields of Evolutionary Optimisation and Automated Artificial Intelligence.
The Minimum Spanning Tree (MST) problem is the challenge of finding a tree in an edge-weighted graph that maintains connectivity of all nodes and has minimal costs among all such trees. The MST problem is a fundamental combinatorial optimisation problem with countless applications, e.g., in the construction of communication networks, medical imaging, or many other areas that range from logistic via graph drawing to power grid network design. The basic single-objective version of the MST problem can be solved efficiently, i.e., in polynomial time, e.g., by Prim’s algorithm. The multi-objective MST (moMST) version though (i.e., multiple weights per edge) is NP-hard and suffers from intractability. Thus, efficient heuristics are needed to approximate the set of optimal trade-off solutions.
Evolutionary Algorithms are randomised search heuristics that are among the most successful when it comes to solving NP-hard multi-objective optimisation problems.
I will present recent work on the design of several highly biased sub-graph-based mutation operators for the moMST problem. In a nutshell, these operators replace (un)connected sub-trees of candidate solutions with locally (Pareto-)optimal sub-trees. The latter (biased) step is realised by applying Kruskal’s single-objective MST algorithm to a weighted sum scalarisation of a sub-graph.
I will detail some runtime complexity results for the introduced operators and demonstrate results that show that the sub-graph based operators beat baseline algorithms from the literature even with severely restricted computational budget in terms of function evaluations on four different classes of complete graphs.
Es laden ein: die Dozentinnen und Dozenten der Informatik
--
Andrea Gibbels, M.A.
Administrative Assistant
Chair for AI Methodology / Lehrstuhl für Methodik der Künstlichen Intelligenz
RWTH Aachen University
E-mail: secret(a)aim.rwth-aachen.de
Phone: +49 241 80 21452
Theaterstr. 35-39
52062 Aachen
Germany
Dear all,
this is a reminder for Nils Nießen's talk with the title "Can Trains Be on Time?" taking place today at 12:30 in the B-IT room 5053.2. Please find the details below
--- Abstract ---
Why are trains always delayed and how is a delay defined at all? In the
talk "Can trains be on time", the influences and conditions in the
occurrence of delays in the railway system will be discussed. The
distribution of buffer times has an influence on the propagation of
delays. Using a two-train model, the mechanisms of delay propagation are
derived. Approaches to increase punctuality and capacity are shown.
----------------
Part of the programme of the research training group UnRAVeL is a series of lectures on the topics of UnRAVeL’s research thrusts algorithms and complexity, verification, logic and languages, and their application scenarios. Each lecture is given by one of the researchers involved in UnRAVeL.
This years topic is "Biggest Milestones - Research at Its Peak", UnRAVeL professors will present the most important milestone of their respective research.
All interested doctoral researchers and master students are invited to attend the UnRAVeL lecture series 2023 and engage in discussions with researchers and doctoral students.
Next week is no talk so that the next one will be held on the 25th May. Here, Jürgen Giesl is going to talk about "Proving Termination with Dependency Pairs".
We are looking forward to seeing you at the lectures.
Kind regards,
Jan-Christoph for the organisation committee
+**********************************************************************
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*
* Einladung
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*
*
* Informatik-Oberseminar
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*
*
+**********************************************************************
Zeit: Freitag, 19. Mai 2023, 13.00 Uhr
Ort: Seminarraum 2202, Hauptbau, Ahornstr. 55
Referent: Christopher Kugler, M.Sc.
Ehem. Lehrstuhl Informatik 11
Thema: Systematic Derivation of Feature-driven and Risk-based Test Strategies for Automotive Applications
Abstract:
The automotive industry is currently characterized by a disruptive change in terms of
electro-mobility and highly autonomous driving. Similarly, new mobility concepts pose
particular challenges for quality assurance measures in automotive product development.
Traditional, experience-based approaches for deriving quality assurance strategies do not
address these challenges and lead to potentially high failure rates during product operation.
Therefore, a risk-based approach for the derivation of feature-specific test strategies
is proposed in this thesis, which enables the objective definition of test end criteria
and, through appropriate prioritization, an increase in the efficiency and effectiveness
of performed verification and validation activities. On the basis of a two-stage risk
assessment, quality assurance measures can initially be defined in early project phases
and then be refined for individual product features as soon as required information is
available. A framework for the derivation of test strategies is presented, which considers
the current state of the art with regard to functional safety and distinguishes the applied
acceptance thresholds for test-end criteria based on previously defined risk classes. The
presented approach is evaluated in context of series development projects, where the
significance of the risk assessment is verified through data analysis. The test strategy
applied in those projects is retrospectively evaluated and compared against the risk-based
approach presented in this thesis in terms of achieved effectiveness and efficiency. Finally,
two different concepts for measuring quality of automotive products are introduced and
profound product release criteria are defined.
Es laden ein: die Dozentinnen und Dozenten der Informatik
Dear all,
this is a reminder for Sebastian Trimpe's talk with the title "Event-Triggered Learning" taking place today at 12:30 in the B-IT room 5053.2. Please find the details below
--- Abstract ---
The ability to learn is an essential aspect of autonomous systems facing uncertain and changing environments. However, the process of learning a new model or behavior often does not come for free, but involves a certain cost. For example, gathering informative data often means to deviate from normal operation, it may be challenging due to physical limitations, or updating models can require substantial computation. Hence, the question of "when to learn?" is essential for the efficient and persistent operation of autonomous systems.
In this talk, I will be discussing recent research on the concept of event-triggered learning (ETL), which we have proposed for making principled decisions on when to learn a new dynamics model or controller. We will present some specific trigger designs that trigger learning when needed, and also highlight experimental application leading to significant resource savings. Moreover, I will give a personal "historical" perspective and trace back, how our recent research was itself triggered by my own PhD research and papers. I will also dare to look into the future and discuss what potential "milestone" papers there might still be to come.
----------------
Part of the programme of the research training group UnRAVeL is a series of lectures on the topics of UnRAVeL’s research thrusts algorithms and complexity, verification, logic and languages, and their application scenarios. Each lecture is given by one of the researchers involved in UnRAVeL.
This years topic is "Biggest Milestones - Research at Its Peak", UnRAVeL professors will present the most important milestone of their respective research.
All interested doctoral researchers and master students are invited to attend the UnRAVeL lecture series 2023 and engage in discussions with researchers and doctoral students.
Next week, Nils Nießen is going to give a talk with the title "Can Trains Be on Time?"
We are looking forward to seeing you at the lectures.
Kind regards,
Jan-Christoph for the organisation committee
Dear all,
this is a reminder for Christina Büsing's talk with the title "Robust Strategic Planning for Mobile Medical Units" taking place today at 12:30 in the B-IT room 5053.2. Please find the details below
--- Abstract ---
Mobile medical units (MMUs) allow for an efficient medical coverage of sparsely populated, spacious areas.
Unfortunately, flexibility comes at the price of a highly complex operation planning process. In this talk,
we investigate the strategic planning of an MMU service by deciding where MMU operation sites should
be set up and how often these should be serviced. To that end, we study the strategic planning problem
for MMUs (SPMMU) – a capacitated set covering problem that includes existing practices and two types
of patient demands: (i) steerable demands representing patients who seek health services through
a centralized appointment system and can be steered to any treatment facility within a given consideration
set and (ii) unsteerable demands representing walk-in patients who always visit the closest available treatment facility.
We propose an integer linear program for the SPMMU that can be solved via Benders decomposition
and constraint generation. All our results transfer to the session-specific SPMMU and we evaluate
our models in a computational study based on a set of instances generated from a rural primary care system in Germany.
----------------
Part of the programme of the research training group UnRAVeL is a series of lectures on the topics of UnRAVeL’s research thrusts algorithms and complexity, verification, logic and languages, and their application scenarios. Each lecture is given by one of the researchers involved in UnRAVeL.
This years topic is "Biggest Milestones - Research at Its Peak", UnRAVeL professors will present the most important milestone of their respective research.
All interested doctoral researchers and master students are invited to attend the UnRAVeL lecture series 2023 and engage in discussions with researchers and doctoral students.
Next week, Sebastian Trimpe is going to give a talk with the title "Event-Triggered Learning"
We are looking forward to seeing you at the lectures.
Kind regards,
Jan-Christoph for the organisation committee
Dear all,
this is a reminder for Martin Grohe's talk with the title "The Quest for a Logic Capturing PTIME" taking place today at 12:30 in the B-IT room 5053.2. Please find the details below
--- Abstract ---
Problems that are hard to describe are hard to solve and
vice versa." This claim may seem naive or just wrong at first sight,
but it is the underlying idea of a deep and fruitful connection
between the descriptive complexity and the computational complexity of
computational problems. Here descriptive complexity refers to the
“language resources” required to express a problem in a formal
language, or logic whereas computational complexity refers to the
computational resources needed to solve the problem.
There are logical characterisations of many common complexity classes
such as NP or PSPACE, but the question of whether there is a logical
characterisation of the class PTIME of polynomial time solvable problems
remains open. It was first asked by Chandra and Harel (1982) in the
context of database theory, and later in a slightly different form by
Gurevich (1988) in the context of finite model theory.
In this talk, I will review the question and speak about negative as
well as positive results spanning the last 40 years.
----------------
Part of the programme of the research training group UnRAVeL is a series of lectures on the topics of UnRAVeL’s research thrusts algorithms and complexity, verification, logic and languages, and their application scenarios. Each lecture is given by one of the researchers involved in UnRAVeL.
This years topic is "Biggest Milestones - Research at Its Peak", UnRAVeL professors will present the most important milestone of their respective research.
All interested doctoral researchers and master students are invited to attend the UnRAVeL lecture series 2023 and engage in discussions with researchers and doctoral students.
Next week, Christina Büsing is going to give a talk with the title "Robust Strategic Planning for Mobile Medical Units"
We are looking forward to seeing you at the lectures.
Kind regards,
Jan-Christoph for the organisation committee
Dear all,
this is a reminder for Erika Ábrahám's talk with the title "Building Bridges between Symbolic Computation and Satisfiability Checking" taking place today at 12:30 in the B-IT room 5053.2. Please find the details below
------
The use of advanced methods to solve practical and industrially relevant
problems by computers has a long history. Symbolic Computation is
concerned with the algorithmic determination of exact solutions to
complex mathematical problems. More recent developments in the area of
Satisfiability Checking started to tackle similar problems but with
different algorithmic and technological solutions.
Though both communities have made remarkable progress in the last
decades, they need to be further strengthened to tackle practical
problems of ever increasing size and complexity. Their separate tools
(computer algebra systems and SMT solvers) are urgently needed to
address prevailing problems having a direct effect on our society. For
example, Satisfiability Checking is an essential backend for assuring
the security and the safety of computer systems. In various scientific
areas, Symbolic Computation is able to deal with large mathematical
problems far beyond the scope of pencil and paper solutions.
Until recently, the two communities have been largely disjoint and
unaware of the achievements of one another, despite there being strong
reasons for them to discuss and collaborate, since they share many
central interests. Researchers from these two communities rarely
interacted, and also their tools lack common, mutual interfaces for
unifying their strengths.
As said, until recently...
------
Part of the programme of the research training group UnRAVeL is a series of lectures on the topics of UnRAVeL’s research thrusts algorithms and complexity, verification, logic and languages, and their application scenarios. Each lecture is given by one of the researchers involved in UnRAVeL.
This years topic is "Biggest Milestones - Research at Its Peak", UnRAVeL professors will present the most important milestone of their respective research.
All interested doctoral researchers and master students are invited to attend the UnRAVeL lecture series 2023 and engage in discussions with researchers and doctoral students.
Next week, Martin Grohe is going to give a talk with the title "The Quest for a Logic Capturing PTIME"
We are looking forward to seeing you at the lectures.
Kind regards,
Jan-Christoph for the organisation committee
+**********************************************************************
*
*
* Einladung
*
*
*
* Informatik-Oberseminar
*
*
*
+**********************************************************************
Zeit: Dienstag, 18.04.2023, 14:00-15:00 Uhr
Der öffentliche Vortrag findet hybrid statt:
Raum: Raum 5053.1 (kleiner B-IT-Hörsaal)/Informatikzentrum, Ahornstraße 55
Zoom: https://rwth.zoom.us/j/95352035574?pwd=anc2VVdzUTQ5TVdSME9mSEJ2SE81Zz09
Meeting-ID: 953 5203 5574
Kenncode: 440352
Referent: Herr Lars Christoph Gleim, M. Sc.
Lehrstuhl Informatik 5
Thema: An Approach for Global and Local Data Lifecycle Management with Provenance and Persistent Identifiers
Abstract:
The increasing complexity of data lifecycle management in inter-organizational collaboration and agile product development has resulted in current data management practices struggling to meet industrial requirements.
To address this, an approach called World Wide Data Management (WWDM) has been developed based on Linked Data technology and principles of findability, accessibility, interoperability, and reusability (FAIR). WWDM provides key services, principles, and best practices for global and local data lifecycle management with provenance and persistent identifiers. The approach includes services for persistent resource identification, infrastructure-independent data persistence, data integration and interoperability, verifiable accountability for data sharing, and integrating the WWDM paradigm with traditional data management in file systems.
WWDM provides a practical foundation to enable inter-organizational data management and collaboration with minimal operational overhead, promoting the adoption of FAIR data management principles and best practices throughout the product lifecycle and enterprise supply chain.
Es laden ein: die Dozentinnen und Dozenten der Informatik
_______________________________
Leany Maaßen
RWTH Aachen University
Lehrstuhl Informatik 5, LuFG Informatik 5
Prof. Dr. Stefan Decker, Prof. Dr. Matthias Jarke,
Prof. Gerhard Lakemeyer Ph.D., JunProf. Dr. Sandra Geisler
Ahornstrasse 55
D-52074 Aachen
Tel: 0241-80-21509
Fax: 0241-80-22321
E-Mail: maassen(a)dbis.rwth-aachen.de