Final General Workshop (Wednesday 16 February 2022)

The workshop is held remotely. We use a ZOOM room, connection details to be announced. The Workshop is organized by NKUA.

Schedule of the Final Workshop / All times are EET.

16.00. Welcome and Intro (Prof Ioannis Emiris, NKUA and Athena Research Center)
16.05. Ethics Advisor: Anna Damilaki (Dryllerakis Associates)
16.20. Κοnstantinos Tertikas (NKUA)
Deep Learning for 3D Points & Images: A Brief Overview
We present recent advances in Deep Learning for 3D Points and Image data. Specifically, we discuss about the Transformer family of architectures, and its basic building block, the self-attention mechanism.”

16.35. Evangelos Bartzos (NKUA)
Point-bar rigidity and meshes
Rigidity theory studies principally the embeddings of simple undirected graphs on the plane or in the space. These embeddings are known as point-bar mechanisms. Here, we  are interested in applications of rigidity construction
steps in the generation of meshes.

16.50. Business Meeting
17.00. Break
17.15. Dr Nikolaos Zygouras (NKUA)
Hybrid Travel Time Estimation
avel time estimation is a critical task, useful to many urban applications at the individual citizen and the stakeholder level. We introduce a novel hybrid algorithm for travel time estimation that leverages historical and sparse real-time trajectory data. Given a path and a departure time we estimate the travel time taking into account the historical information, the real-time trajectory data and the correlations among different road segments. We detect similar road segments using historical trajectories, and use a latent representation to model the similarities.

17.30. Dimitris Katsiros (NKUA)
AI Forecasting
Wind farms require access to high resolution and high accuracy meteorological forecasting, so as to enable precise prediction of energy production and in turn drive energy trading. We introduce a pipeline that exploits spatial features extracted from the WRF model and utilizes deep learning techniques. Our results indicate that deep learning can significantly improve performance compared to traditional methods.
17.45. Conclusion

The list of participants includes: Prof D. Gunopulos, Dr I. Chamodrakas, Lydia Themeli,  Efthymia Malesiou, Giannis Rovithakis, Lazaros Avgeridis, Thomas Pappas, Charalambos Tzamos (NKUA), Seena Rejal (3DI), Dr Detyniecki Marcin, Boutharouite Chaouki (AXA)


Workshop on Retrieval and Shape analysis (Thursday 14 May 2020)

This focused workshop serves the presentation of research performed in the Project’s WP2 (Retrieval and Shape analysis), and the coordination of further related activities, including our work in 3D shape learning.

The workshop is held remotely due to Covid-19 travel restrictions. We use a ZOOM room. The Workshop is organized by NKUA and by 3DI /

Schedule of Workshop – final

All times are London, UK times.

12.55. Welcome and Intro (Ioannis Emiris, NKUA and Seena Rejal, 3DI)
13.00. Andre’ Lieutier (Dassault Systemes): Learning and Topology.
13.30. Yannis Avrithis (INRIA Rennes): Unsupervised and Semi-supervised Learning on manifolds
14.00. Break
. Yanir Kleiman (3DI, London): Generative Modeling: From Point Clouds to Meshes
15.00. Emmanouil Christoforou (NKUA): Unsupervised Feature Learning on 3D Point Clouds
15.30. Alexander Georgiou (NKUA): 3D Deep Clustering.
15.45. Conclusion.

There were more than 20 participants, including: D. Gunopulos, I. Chamodrakas, C. Konaxis, Α. Karasoulou, N. Zygouras, several PhD / MSc students (NKUA), V. Kalogeraki (AUEB), A. Saravanou (NKUA/Stanford), S. Shankar, A. Kendall (3DI), J. Michailidis (Airbus, Hamburg), P. Achlioptas (Stanford).


H2020 MSCA cluster event “Artificial Intelligence” (10-11 December 2019)

The Marie Sklodowska-Curie Action (MSCA) units of the Research Executive Agency (REA) joined forces and organised, together with the Directorate General Education, Youth, Sport and Culture (DG EAC), a cluster event dedicated to Artificial Intelligence (AI). On December 10th and 11th, 2019, more than 50 MSCA researchers, 40 European Commission policy makers and 50 REA representatives gathered to discuss the latest AI developments in the digital, health and environment sectors. The event aimed at:

  • showcasing the contribution of MSCA projects to the relevant sub-domains of AI,
  • enhancing synergies among projects and create/reinforce networking opportunities, particularly for MSCA fellows,
  • promoting discussion and collect information to provide coordinated input to the relevant EU policy-making level.

37 MSCA project representatives presented their work in panel / poster sessions, while representatives from the European Commission provided AI perspectives on ethics, education and security. They discussed how the EU could position itself as front-runner in setting trustworthy and ethical by-design AI.

LAMBDA participated in the Horizon 2020 MSCA cluster event “Artificial Intelligence” with a presentation by Ph.D. candidate N. Zygouras (working under the supervision of Professor D. Gunopulos, NKUA) on the topic “Mining Mobility Data”.

The meeting report for policy consideration is available online.


Workshop on Un/Semi-supervised learning and Data Mining (14-15 October 2019)

This focused workshop serves the presentation of research performed in WP3 (Unsupervised and semi-supervised learning) and the coordination of further activities. It is hosted by AXA at their Paris premises: 61, rue Mstislav Rostropovich, Paris 75017.

Schedule of Workshop

Monday. 14/10.
13.15. Welcome and Intro (I. Emiris, and AXA)
13.30. Unsupervised detection of adversarial collaboration for pedestrian indoor mobility (M. Sammarco, AXA)
14.30. Map-matching algorithm for telematics car insurance (P. Martial, AXA)
15.30. Coffee break
16.00. Fast, safe and efficient routing (N. Zygouras, NKUA) Download PDF
17.00. Business meeting
17.30. End of 1st day
19.30. Social Dinner at “Coretta”, 151 bis r. Cardinet, 75017 Paris.

Tuesday 15/10 (room ABBA, 7th floor).
09.30. Learning Language for Shape Differentiation (P. Achlioptas, Stanford U.)
10.30. Coffee Break
11.00. Road segmentation, clustering & abnormality detection (I. Chamodrakas, NKUA) Download PDF
12.00. Clustering of one-dimensional objects (E. Christoforou, NKUA) Download PDF
13.00. Lunch Break
14.30. Data-driven methods for financial modeling (A. Chalkis, NKUA) Download PDF
15.30. Conclusions, Outlook and Plans (ALL)
16.00. End of Workshop

PARTICIPANTS include, besides the speakers, L. Themeli (National Kapodistrian U. Athens).


Midterm Meeting (25-28 September 2018)

It serves for reporting and making sure execution of the Project follows the expected plans. It is hosted by 3DI at their London HQ: 1 Berkeley Street, Mayfair, London. On this occasion, the Midterm Review occurs (Thursday 27/9 afternoon to Friday 28/9 noon).

The meeting includes a General Software Workshop (25-27/9), which is a means to coordinate innovation activities based on software development, to review software standards that must be followed by developers in view of integrating their methods to libraries, and to discuss topics related to scaling up our methods for addressing big data. The Workshop includes talks by our members, our USA partners, and by invited speaker Prof. Anne Driemel (TU Eindhoven).

Schedule of Workshop

Tu. 25/9: Arrival
W. 26/9, 10.00-12.30: Informal discussions
W. 26/9, 14.00-16.00: Consortium talks
W. 26/9, 16.00-18.00: Board meeting

Th. 27/9, morning: Invited speakers

9.00 – 10.00    Panagiotis Achlioptas, Stanford University (Remotely)

Learning Fine-Graned Distinctions of 3D Objects from Referential Language

Human world knowledge is highly structured and flexible. When people see an object, they represent it not as a pixel array but as a coherent object consisting of semantic parts. Similarly, when people refer to an object, they provide descriptions that are not merely true but relevant in the current context.  In this work, we harness human behavior in a challenging, grounded reference game task to learn fine-grained correspondences between language and the contextually relevant geometric properties of structured 3D objects. We demonstrate high-performing neural listeners and speakers and introduce a novel dataset containing utterances referring to objects from ShapeNet across a wide diversity of contexts. Using targeted lesions of visual and linguistic input, we show that our systems learn to depend on part words and associate them with the corresponding geometric elements.  Moreover, we find that a context-sensitive neural speaker that plans utterances according to how an imagined listener would interpret their words, in context, produces high quality shape descriptions.

10.15 – 11.15  Anne Driemel (TU Eindhoven,

Searching under the Frechet distance

Similarity search is a fundamental data analysis task. When the input data consists of trajectories or time series, the standard Euclidean distance is unable to capture the similarity properly, unless the data is heavily normalized, preprocessed, or observed only in a feature space. In order to make the similarity search meaningful on the raw data, it is desirable to support more flexible distance measures such as the Frechet distance or Dynamic Time Warping (DTW). Unfortunately, it is an open problem how to build efficient data structures that support similarity search under the Frechet distance. In this talk I will present some recent advances in this area, in particular, I will present a volume argument showing a lower bound on the space-query-time tradeoff and practical approaches based on LSH that might serve as a remedy. Time permitting, I will also present some recent results on the related problem of clustering curves under the Frechet distance.

11.30-12.30 Consortium talks

Venue for the Workshop on Wednesday

Citadines Hotel Lobby (Citadines Holborn-Covent Garden London, located on 94-99 High Holborn, London WC1V 6LF )

Schedule of Midterm Review

Thursday 27 Sep.

Round-table Introduction

14:00-14:10  Round the table Introduction (All)

14:10-14:40  Intro: Status, Financial/administrative issues, ethics, secondments, risks, deviations, dissemination, networking, Deliverables, Tasks, Milestones (Emiris)

14:40-15:00  WP1: Rigorous methods and software (I. Emiris, WP Leader; I. Psarros, secondee)

15:00-15:15  Coffee Break

15:15-15:35  WP2: Retrieval and Shape analysis (S. Rejal, WP Leader; E. Anagnostopoulos, secondee)

15:35-15:55  WP3: Unsupervised and semi-supervised learning (M. Detyniecki, WP Leader; I. Chamodrakas, E. Christophorou, secondees)

15:55-16:15  WP4a. Training: Transfer of Knowledge and Networking, secondments, transfer of knowledge, career opportunities (S. Rejal, WP Leader)

16.15-16.35  WP4b. Dissemination and Communication (S. Rejal, WP Leader)

16:35-16:50  Coffee Break

16:50-17.10  WP5: Project Management (I. Emiris, WP Leader)

17.10-17:30  WP6: Ethics Requirement (I. Emiris, WP Leader)

Dinner 18.30 at The Square Pig, 30 – 32 Procter Street London, WC1V 6NX

Friday 28 Sep.

09:30-10:30     Meeting between secondees and the REA Project Officer (Secondees)
In parallel: Meeting between site leaders and Innovation expert,  discussion on pre-identified innovation aspects (see questionnaire)

10:30-11.00     Coffee Break

11.00-12.00     Open Discussion (All)

12.00-12:30     Summary of Agreed action points (Emiris)

12:30-13.00     Recommendations Overview (Project Officer)

13.00-14.00     Project Lunch

Venue for the Midterm Review

Citadines Holborn-Covent Garden London, located on 94-99 High Holborn, London WC1V 6LF near the Holborn Tube station (contact phone number 0207 395 8800). Conference rooms are located on the ground floor past the reception. Please note that the workshop will be held on Thursday 27th in the “Sydney” conference room and Friday 28th in the “Berlin” conference room.

Kickoff General Workshop (6-8 June 2017)

It serves for academic and industrial members to present the expertise they bring into LAMBDA as well as open problems in which they are working, thus finalising the planned work. Moreover, it serves for organising technology transfer, benchmarking, and joint software development. There shall be an invited speaker.

The meeting will be held on Wednesday, 7th June 2017 and Thursday 8th June 2017, 09.00-17.00. Since participants are expected to arrive on Tuesday, June 6th, a social event may be planned on Tuesday evening. Sessions on Wednesday and Thursday shall be held in the A56 conference room of the Department of Informatics & Telecommunications, at the Campus of National & Kapodistrian University of Athens at Ilisia.

Confirmed participants from all beneficiaries include: M. Detyniecki, I. Emiris, D. Gunopulos, I. Hamodrakas, S. Rejal, X. Renard. Partner participant: Panos Achlioptas (Stanford U.). The ethics adviser has also confirmed participation. Invited speakers: Prof. Joachim Giesen, and Dr. Soeren Laue (Univ. Jena, Germany).


Wed. 9.00. Welcome and Intro (Emiris). Team of NKUA (Emiris, Gunopulos).
10.30. Team of 3DI (Rejal).
11.30. Team of AXA (Detyniecki, Renard).
14.30. Proximity problems in high dimensions (Psarros, NKUA)
15.30. Web-scale clustering (Anagnostopoulos, NKUA)
20.00. SOCIAL DINNER at “Mpousoulas

Thu. 9.00. Invited talk: Scaling Up Generic Optimization for Data Analytics (Giesen and Laue).
10.30. Supervisory board meeting
11.30. Predictive Learning for 3D Point Clouds (Achlioptas).
14.30. A General Framework for First Story Detection  Utilizing Entities and their Relations (Panagiotou, NKUA)
15.30. ChEsS: Cost-Effective Scheduling across multiple heterogeneous mapreduce clusters (Zachilas, Kalogeraki, AUEB)

Practical information

Lunch will be provided on Wednesday and Thursday, as well as a workshop dinner on Wednesday evening. A social event may be organised on Tuesday evening.

Please arrange for your own hotel accommodation (unless you are invited). Suggested hotels in the area (in order of increasing price): Delice Hotel & Apartments (website). Ilisia Best-Western. Divani-Caravel Hotel, on Vassileos Alexandrou Ave. Athens Hilton Hotel.

Directions from Athens International Airport: see also transport from the airport: The best is to use Metro Line 3, and get off at “Evangelismos” stop. Timetable: 05:30-24:00; frequency: 30′. Taxis: their stand is at the Arrivals Level; fee: 40 to 50 Euro. With the Express Airport Bus X95 (to Syntagma sq.): get off at the Hilton Bus Stop; it runs on a 24-hour basis.
Directions to Dept. Informatics & Telecoms from the hotels. There’s 2 bus lines for which you need a valid metro ticket or a bus ticket, to be bought at a kiosk before entering the bus. Bus 250 goes in the campus, drops you off in front of the department (Bus Stop: 2nd PANEPISTIMIOPOLIS). Alternatively use “224”, get off at stop “10th KESSARIANIS”, on “Ethnikis Antistaseos” Ave, turn left and walk 100m. Here is a Google map to the Dept of Informatics from “Evangelismos” metro stop (or the hotels). See also the School of Science.

Satellite event:  Summer school “Techniques in Random Discrete Structures“, University of Athens, Greece, May 22-27, 2017.