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4. SpotTheFake: An Initial Report on a New CNN-Enhanced Platform for Counterfeit Goods Detection

Author

Şerban, Alexandru, Ilaş, George, and Poruşniuc, George-Cosmin

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Artificial Intelligence, Electrical Engineering and Systems Science - Image and Video Processing, I.2.1, I.4.9
Abstract

The counterfeit goods trade represents nowadays more than 3.3% of the whole world trade and thus it's a problem that needs now more than ever a lot of attention and a reliable solution that would reduce the negative impact it has over the modern society. This paper presents the design and early stage development of a novel counterfeit goods detection platform that makes use of the outstsanding learning capabilities of the classical VGG16 convolutional model trained through the process of "transfer learning" and a multi-stage fake detection procedure that proved to be not only reliable but also very robust in the experiments we have conducted so far using an image dataset of various goods which we gathered ourselves., Comment: 7 pages, 13 figures

Published
2020

7. Counterexample-Guided Strategy Improvement for POMDPs Using Recurrent Neural Networks

Author

Carr, Steven, Jansen, Nils, Wimmer, Ralf, Serban, Alexandru C., Becker, Bernd, and Topcu, Ufuk

Subjects
Computer Science - Artificial Intelligence, Computer Science - Machine Learning
Abstract

We study strategy synthesis for partially observable Markov decision processes (POMDPs). The particular problem is to determine strategies that provably adhere to (probabilistic) temporal logic constraints. This problem is computationally intractable and theoretically hard. We propose a novel method that combines techniques from machine learning and formal verification. First, we train a recurrent neural network (RNN) to encode POMDP strategies. The RNN accounts for memory-based decisions without the need to expand the full belief space of a POMDP. Secondly, we restrict the RNN-based strategy to represent a finite-memory strategy and implement it on a specific POMDP. For the resulting finite Markov chain, efficient formal verification techniques provide provable guarantees against temporal logic specifications. If the specification is not satisfied, counterexamples supply diagnostic information. We use this information to improve the strategy by iteratively training the RNN. Numerical experiments show that the proposed method elevates the state of the art in POMDP solving by up to three orders of magnitude in terms of solving times and model sizes.

Published
2019

8. Adversarial Examples - A Complete Characterisation of the Phenomenon

Author

Serban, Alexandru Constantin, Poll, Erik, and Visser, Joost

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Cryptography and Security, Computer Science - Machine Learning, Computer Science - Neural and Evolutionary Computing
Abstract

We provide a complete characterisation of the phenomenon of adversarial examples - inputs intentionally crafted to fool machine learning models. We aim to cover all the important concerns in this field of study: (1) the conjectures on the existence of adversarial examples, (2) the security, safety and robustness implications, (3) the methods used to generate and (4) protect against adversarial examples and (5) the ability of adversarial examples to transfer between different machine learning models. We provide ample background information in an effort to make this document self-contained. Therefore, this document can be used as survey, tutorial or as a catalog of attacks and defences using adversarial examples.

Published
2018

10. Safe Reinforcement Learning via Probabilistic Shields

Author

Jansen, Nils, Könighofer, Bettina, Junges, Sebastian, Serban, Alexandru C., and Bloem, Roderick

Subjects
Computer Science - Artificial Intelligence
Abstract

This paper targets the efficient construction of a safety shield for decision making in scenarios that incorporate uncertainty. Markov decision processes (MDPs) are prominent models to capture such planning problems. Reinforcement learning (RL) is a machine learning technique to determine near-optimal policies in MDPs that may be unknown prior to exploring the model. However, during exploration, RL is prone to induce behavior that is undesirable or not allowed in safety- or mission-critical contexts. We introduce the concept of a probabilistic shield that enables decision-making to adhere to safety constraints with high probability. In a separation of concerns, we employ formal verification to efficiently compute the probabilities of critical decisions within a safety-relevant fragment of the MDP. We use these results to realize a shield that is applied to an RL algorithm which then optimizes the actual performance objective. We discuss tradeoffs between sufficient progress in exploration of the environment and ensuring safety. In our experiments, we demonstrate on the arcade game PAC-MAN and on a case study involving service robots that the learning efficiency increases as the learning needs orders of magnitude fewer episodes.

Published
2018

13. A Security Analysis of the ETSI ITS Vehicular Communications

Author

Serban, Alexandru Constantin, Poll, Erik, Visser, Joost, Hutchison, David, Series Editor, Kanade, Takeo, Series Editor, Kittler, Josef, Series Editor, Kleinberg, Jon M., Series Editor, Mattern, Friedemann, Series Editor, Mitchell, John C., Series Editor, Naor, Moni, Series Editor, Pandu Rangan, C., Series Editor, Steffen, Bernhard, Series Editor, Terzopoulos, Demetri, Series Editor, Tygar, Doug, Series Editor, Weikum, Gerhard, Series Editor, Gallina, Barbara, editor, Skavhaug, Amund, editor, Schoitsch, Erwin, editor, and Bitsch, Friedemann, editor

Published
2018
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21. New IT Tools and Methods Improving Lifestyle of Young People

Author

Serban, Alexandru, Crisan-Vida, Mihaela, Serban, Maria-Corina, Stoicu-Tivadar, Lacramioara, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Kobsa, Alfred, Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Weikum, Gerhard, Series editor, Istrail, Sorin, Series editor, Pevzner, Pavel, Series editor, Waterman, Michael S., Series editor, Ortuño, Francisco, editor, and Rojas, Ignacio, editor

Published
2015
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27. Socket Programming in .NET

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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28. Authentication Protocols

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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29. Multicast Sockets

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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30. UDP

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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31. Streams in .NET

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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32. TCP

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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33. IPv6

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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34. Raw Socket Programming

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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35. Network Programming in .NET

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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36. Networking Concepts and Protocols

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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37. Cryptography in.NET

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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38. E-mail Protocols

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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39. HTTP

Author

Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, Serban, Alexandru, Nagel, Christian, Mungale, Ajit, Kumar, Vinod, Laghari, Nauman, Krowczyk, Andrew, Parker, Tim, Sivakumar, S. Srinivasa, and Serban, Alexandru

Published
2004
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