A5017991461- Optimization and Search Problems
- Cryptography and Data Security
- Optimization and Packing Problems
- Cryptographic Implementations and Security
- Complexity and Algorithms in Graphs
- Advanced Graph Theory Research
- Scheduling and Optimization Algorithms
- Security and Verification in Computing
- Advanced Manufacturing and Logistics Optimization
- Internet Traffic Analysis and Secure E-voting
- Coding theory and cryptography
- Advanced Steganography and Watermarking Techniques
- Advanced Malware Detection Techniques
- Formal Methods in Verification
- Privacy-Preserving Technologies in Data
- Advanced Optimization Algorithms Research
- Auction Theory and Applications
- Atomic and Molecular Physics
- graph theory and CDMA systems
- Chaos-based Image/Signal Encryption
- Machine Learning and Algorithms
- semigroups and automata theory
- Adversarial Robustness in Machine Learning
- Algorithms and Data Compression
- Advanced Authentication Protocols Security
Johannes Gutenberg University Mainz
2022-2025
University of Lübeck
2015-2024
Technical University of Applied Sciences Lübeck
2024
Alexion (Germany)
2023
Technical University of Munich
2021
Kiel University
2014-2020
TU Dresden
2015
Abstract The atomic structure of neptunium (Np) was investigated by two-step resonance ionization spectroscopy. study involved exploring ground-state transitions as well following to high-lying states just below the potential (IP) or auto-ionizing above IP. That resulted in identification schemes, suitable for trace analysis and nuclear investigations. lifetimes two excited located at 25,342.48 $$\, \text {cm}^{-1} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow>...
The goal of an algorithm substitution attack (ASA), also called a subversion (SA), is to replace honest implementation cryptographic tool by subverted one which allows leak private information while generating output indistinguishable from the output. Bellare, Paterson, and Rogaway provided at CRYPTO '14 formal security model capture this kind attacks constructed practically implementable ASAs against large class symmetric encryption schemes. At CCS'15, Ateniese, Magri, Venturi extended...
We report on high-resolution laser spectroscopy studies $^{249\text{--}253}\mathrm{Cf}$ with spectral linewidths in the order of 100 MHz carried out at RISIKO mass separator Mainz University. In total three atomic ground-state transitions were investigated and hyperfine parameters for odd-$A$ isotopes isotope shift all examined have been determined from measured spectra. The measurements allowed tracking changes mean-squared charge radii across deformed nuclear shell closure $N=152$, whereby...
While the theoretical aspects concerning computation of tree width - one most important graph parameters are well understood, it is not clear how can be computed practically. We present open source Java library Jdrasil that implements several different state art algorithms for this task. By experimentally comparing these algorithms, we show default choices made in lead to an competitive implementation (it took third place first PACE challenge) while also being easy use and extend.
Parameterized complexity theory has led to a wide range of algorithmic breakthroughs within the last few decades, but practicability these methods for real-world problems is still not well understood. We investigate one fundamental approaches this field: dynamic programming on tree decompositions. Indisputably, key technique in parameterized algorithms and modern algorithm design. Despite enormous impact approach theory, it very little influence practical implementations. The reasons...
The security of digital communication relies on few cryptographic protocols that are used to protect internet traffic, from web sessions instant messaging. These and the primitives they rely have been extensively studied considered secure. Yet, sophisticated attackers often able bypass rather than break mechanisms. Kleptography or algorithm substitution attacks (ASA) describe techniques place backdoors right into primitives. While highly relevant as a building block, we show real danger ASAs...
Residuality plays an essential role for learning finite automata. While residual deterministic and non-deterministic automata have been understood quite well, fundamental questions concerning alternating (AFA) remain open. Recently, Angluin, Eisenstat, Fisman (2015) initiated a systematic study of AFAs proposed algorithm called AL* – extension the popular L* to learn AFAs. Based on computer experiments they conjectured that produces AFAs, but not able give proof. In this paper we disprove...
The quantum-mechanical nuclear-shell structure determines the stability and limits of existence heaviest nuclides with large proton numbers Z ≳ 100 (refs.
The adoption of machine learning solutions is rapidly increasing across all parts society. As the models grow larger, both training and inference increasingly outsourced, e.g. to cloud service providers. This means that potentially sensitive data processed on untrusted platforms, which bears inherent security privacy risks. In this work, we investigate how protect distributed systems, focusing deep convolutional neural networks. most common best-performing mixed MPC approaches are based HE,...
The adoption of machine learning solutions is rapidly increasing across all parts society. Cloud service providers such as Amazon Web Services, Microsoft Azure and the Google Platform aggressively expand their Machine-Learning-as-a-Service offerings. While widespread has huge potential for both research industry, large-scale evaluation possibly sensitive data on untrusted platforms bears inherent security privacy risks. Since computation time expensive, performance a critical factor...
We consider the fully dynamic bin packing problem, where items arrive and depart in an online fashion repacking of previously packed is allowed. The goal is, course, to minimize both number bins used as well amount repacking. A recently introduced way measuring costs at each timestep migration factor, defined total size repacked divided by arriving or departing item. Concerning trade-off between if we wish achieve asymptotic competitive ratio 1 + epsilon for bins, a relatively simple...
MPC-in-the-head based protocols have recently gained much popularity and are at the brink of seeing widespread usage. With use come spectres implementation issues attacks such as side-channel attacks. We show that implementations implementing paradigm vulnerable to As a case study, we choose ZKBoo-protocol Giacomelli, Madsen, Orlandi (USENIX 2016) even single leaked value is sufficient break security protocol. To this attack not just theoretical vulnerability, apply differential power...
In medical research, there are constantly new findings that lead to insights and novel treatments. Hence, physicians always need stay up-to-date provide high-quality patient care. Virtual reality is unique among the available learning methods as it offers opportunity collaboratively explore inside of human body experience understand complex workings interventions. We realized such a VR-Learning-System assessed its potential with experts (n = 9). Initial results indicate prefer system,...
The microarchitectural behavior of modern CPUs is mostly hidden from developers and users computer software. Due to a plethora attacks exploiting behavior, security-critical software must, e.g., ensure their code constant-time, which cumbersome usually results in slower programs. In practice, small leakages are deemed not exploitable still remain the codebase. For example, sub-cache-line have previously been investigated CacheBleed MemJam attacks, impractical on platforms.In this work, we...
We present the first complexity-theoretic secure steganographic protocol which, for any communication channel, is provably secure, reliable, and has nearly optimal bandwidth. Our system unconditionally i.e. our proof does not rely on unproven assumption, like e.g. existence of one-way functions. This disproves claim that functions access to a channel oracle are both necessary sufficient conditions steganography, in sense reliable steganography exists independently
Implementations of cryptographic libraries have been scrutinized for secret-dependent execution behavior exploitable by microarchitectural side-channel attacks. To prevent unintended leakages, most moved to constant-time implementations primitives. There also efforts certify use in sensitive areas, like Microsoft CNG and Botan, with specific attention leakage behavior.