Ruhr-Universität Bochum (RUB): Open Journal Systems
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Structural representation and the Newman problem of the brain and AI
No full textThe brain is an operationally closed system. At it’s boundary, every incoming signal gets translated into neural activity. The intrinsic nature of the distal causes perturbing the brain at its sensory surfaces cannot be grasped from the inside. Moreover, the brain exploits change detection and relational coding. Hence, the external relations between any distal causes are transformed into internal relations between neural activities. The picture of a thoroughgoing structuralism about the mind emerges: all mental states are relationally individuated and thereby provide structural representations. But structuralism is vulnerable to a rather generic logico-mathematical problem: the Newman problem. The specific “Newman problem of the brain” is the concern that the brain’s operational closure is accompanied by a representational closure, where neither the intrinsic nature of the distal causes nor the nature of the external relations can be grasped from the inside. Potentially, this applies to any operationally closed structural representation system, including brains and AI systems. If the Newman problem persists, then such systems “know” nothing, the outside world remains completely hidden. This is nothing less than a skeptical scenario of the most extreme form. However, I will present a solution to this conundrum. It works by “spatio-temporal grounding”: spatial and temporal relations are unalteredly transferred from the external world to systems of structural representation
Country Report: Programmes of Philosophical Subjects in Primary and Secondary Schools in Serbia
Get PDFPhilosophical subjects exist in primary and secondary schools in Serbia. In primary schools, pupils can elect to attend a "Philosophy with Children" free teaching activity. Certain secondary schools have philosophical subjects as compulsory or elective courses. Gymnasium pupils often have a two-year "Philosophy" subject, while some vocational schools have subjects like "Logic", "Ethics", "Logic with Ethics", "Medical Ethics", which are most often elective courses with a few exceptions. Although philosophical subjects are declared to be useful in developing pupils\u27 reasoning and critical thinking skills, there is a tendency towards reducing the presence of philosophical subjects in school curricula, especially in vocational schools
Review: Böhner, Ines K. / Chojnacki-Herbers, Gretchen / Michaels, Joseph / Nixon, John D.: English for Science and Technology (C1).
No full textBöhner, Ines K. / Chojnacki-Herbers, Gretchen / Michaels, Joseph / Nixon, John D.: English for Science and Technology (C1).Review: Böhner, Ines K. / Chojnacki-Herbers, Gretchen / Michaels, Joseph / Nixon, John D.: English for Science and Technology (C1)
Buck, Isabella: Wissenschaftliches Schreiben mit KI.
Get PDFBuck, Isabella: Wissenschaftliches Schreiben mit KI.Buck, Isabella: Wissenschaftliches Schreiben mit KI
Attacking Split-and-Lookup-Based Primitives Using Probabilistic Polynomial System Solving: Applications to Round-Reduced Monolith and Full-Round Skyscraper
No full textIn recent years, many hash functions have been introduced to satisfy the pressing need of some zero-knowledge protocols for such primitives allowing a low degree verification of their round function when arithmetized over a large field.While this can be achieved by restricting their sub-components to low-degree functions (and their inverse), the newest primitives in this category also leverage the intricacies of some proof systems to use “Split-and-Lookup” non-linear functions that essentially apply a small S-box in parallel over the binary representation of a field element.Such components excel at hindering attacks relying on polynomial system solving, but they offer poor security against statistical attacks. On the other hand, low degree monomials offer the opposite guarantees, being strong against statistical attacks. Several primitives have recently been proposed that combine such components in different ways in order to get the best from both.In this paper, we target such primitives by relying on the low degree components to allow a low-cost polynomial solving step. The weakness of Split-and-Lookups against linear attacks is used to simplify these systems, and their weakness against differential attacks is then used to propagate across many rounds the differential patterns obtained during polynomial solving. We instantiate this general approach by attacking round-reduced Monolith, and providing a distinguisher on full-round Skyscraper. These result then shed some light on how to best combine the different types of components to achieve the highest security
Pushing The Area Limit of Composable Gadgets: Low-Area Hardware Masked Circuits with Fewer Sources of Randomness
No full textWith the dramatic increase of easily accessible IoT devices, there is a growing demand to protect these cryptographic hardware implementations against Side-Channel Analysis (SCA) attacks. Among various proposed countermeasures against SCA, masking is a widely adopted countermeasure. Constructing a correct and secure masking hardware scheme is a challenging task, even for experienced engineers. Composable gadgets have recently been proposed to facilitate the process of masking large circuits by using the free composition property. For the composable gadget design, besides composability, minimizing hardware overhead in the overall composable masking scheme is also an important factor. To reduce the area overhead, we propose first- and second-order composable gadgets based on a ring circuit design, named OBS. The design of the ring circuit reduces the number of registers and sources of randomness, thereby reducing the area of the gadgets. From the perspective of composing large masked circuits, we propose several optimization methods based on the characteristics of ring circuits, such as register optimization, frozen technique and bubble strategy. These optimization methods can further optimize the overall area of the masked circuit. Furthermore, we also provide the proof of the first- and second-order security of the OBS gadgets under the glitch- and transition-extended probe model. To show the area advantage of the OBS schemes, we give the are comparison results with other schemes at the gadget level and masked circuit level. The best optimization rate compared to the state-of-the-art can reach 40% for the AES S-box. The comparison results of different implementations show that our scheme outperforms various other composable masking schemes in terms of area overhead. We also use the formal verification tool SILVER and practical FPGA-based experiments to confirm the claimed first- and second-order security
Constant-Cycle Hardware Private Circuits
No full textThe efficient implementation of Boolean masking with minimal overhead in terms of latency has become a critical topic due to the increasing demand for physically secure yet high-performance cryptographic primitives. However, achieving low latency in masked circuits while ensuring that glitches and transitions do not compromise their security remains a significant challenge. State-of-the-art multiplication gadgets, such as the recently introduced HPC4 (CHES 2024), offer composable security against glitches and transitions, as proven under the robust d-probing model. However, these gadgets require at least one clock cycle per computation, resulting in a latency overhead that increases with the algebraic degree. In contrast, LMDPL gadgets (CHES 2014 & CHES 2020) can achieve fixed latency independent of the algebraic degree, effectively addressing this issue. However, they are limited to two shares, and extending them to guarantee composable security at order d with d + 1 shares is considered an open challenge.In this work, we introduce Constant-Cycle Hardware Private Circuits (CCHPC), a novel hardware masking scheme built on the concept of LUT-based Masked Dual-Rail with Pre-charge Logic (LMDPL). Specifically, CCHPC achieves a fixed latency of d clock cycles by masking a Boolean function of arbitrary algebraic degree with d + 1 shares. CCHPC gadgets are secure and trivially composable, as formally proven under the Robust but Relaxed d-probing model (CHES 2024). Using CCHPC gadgets, we design a masked Advanced Encryption Standard (AES) encryption core which can be instantiated for an arbitrary number of d + 1 shares with a total latency of 11 + d clock cycles
Fault Injection Evaluation with Statistical Analysis: How to Deal with Nearly Fabricated Large Circuits
No full textA critical aspect of securing cryptographic hardware is their resistance to Fault Injection (FI) attacks, which involve the successful injection of faults into the system in operation. Specifically, a hardware design must be resilient to wellestablished fault injection techniques, including voltage or clock glitching, laser fault injections, and the more recently introduced Electromagnetic Fault Injection (EMFI). Ideally, the protection level must be verified before the chip is fabricated. Although initial efforts to verify the resistance of hardware designs against fault injection have been made, analyzing the security of practical designs with realistic gate counts under fault injections that affect multiple gates or the entire circuit state remains a significant challenge. This scenario, however, is considered more realistic than assessing resistance to a fixed, relatively small number of faults. In this work, we introduce FIESTA, a versatile automated framework for analyzing the resistance of hardware circuits under the general random fault model. By leveraging a nonexhaustive approach, FIESTA is capable of evaluating larger designs compared to state-of-the-art tools, while maintaining a reasonable level of confidence. FIESTA supports various adversary models, allowing customized resistance analysis against specific adversaries. In particular, we present a concrete procedure for evaluating more realistic precise adversaries, based on practical observations. Using FIESTA, we assessed the resistance of several (protected) Advanced Encryption Standard (AES) cores
Avengers assemble! Supervised learning meets lattice reduction: A single power trace attack against CRYSTALS-Kyber Key Generation
No full textIn this paper, we attack Kyber’s key-generation algorithm using power analysis and lattice reduction. More specifically, we target the Centered Binomial Distribution (CBD) sampler which generates the secret data of the underlying Learning With Error (LWE) instance. From a side-channel perspective, our attack uses a single trace, leveraging classifiers developed through supervised learning. We enhance the classification with the AdaBoost strategy, which provides more reliable results and exploitable statistics, enabling the identification of error-free classified samples. In optimal scenarios, our classifiers, combined with the outputted statistics, allow us to recover up to 68% of the secret key’s coefficients from the trace, ensuring that these recovered coefficients are error-free. In such cases, we show that the secret keys can be recovered by Gaussian elimination over a finite field in a few seconds. For less advantageous cases, we assess the block-size in lattice reduction that would complete the key recovery, providing a fine-grained trade-offs between the correctly guessed proportion and the block-size, based on standard estimates. Finally, we conducted large-scale experiments, from power traces to secret key recovery (for most of the instances) under a threshold of 18 hours, targeting all three Kyber’s security levels. Our average rate of success across all security level is more than 96%
Narratological knowledge for teachers: Didactic modelling of a threshold concept in literary studies
Get PDFAbstract: Der Beitrag setzt sich zunächst mit der grundlegenden Frage auseinander, welche theoretisch-konzeptionellen Ansätze für die Auswahl und Gestaltung von literaturwissenschaftlichen Wissensangeboten für das Lehramtsstudium Deutsch fruchtbar gemacht werden können. Dabei werden insbesondere die Ansätze der Basiserkenntniskonzepte (Pohl, 2020) und threshold concepts (Meyer & Land, 2003) aufgegriffen. Ausgehend von der Annahme, dass die erzählerische Vermittlung ein literaturwissenschaftliches Schwellenkonzept ist, wird die Notwendigkeit einer didaktischen Modellierung narratologischen Wissens begründet und es werden Anforderungen an ein solches Modell hergeleitet. Im Zentrum des Beitrags steht die Vorstellung eines Modells zur Erschließung erzählerischer Vermittlung, das als Brücke zwischen fachwissenschaftlichem narratologischen Wissen und dem in didaktischen Anwendungssituationen verstehensrelevanten Wissen fungieren soll. Dieses Modell zeichnet sich durch die Kombination dreier Merkmale aus: (1) Hierarchisierung der Kategorien der Erzähltextanalyse (Wer erzählt? –> Wie? –> Was?), (2) Nutzung verstehensanregender Fragen statt abstrakter Termini, (3) Verknüpfung der drei Analyseebenen: Welches Bild vom Was wird durch die Vermittlung erzeugt?Abstract: First, the article addresses the fundamental question of which theoretical and conceptual approaches can be applied fruitfully to discussions about the selection and design of literary knowledge for teacher training in German. In particular, it considers the approaches of basic knowledge concepts (Basiserkenntniskonzepte, Pohl, 2020) and threshold concepts (Meyer & Land, 2003). Assuming that narrative transmission is a threshold concept in literary studies, the article explains the necessity of didactic modelling of narratological knowledge and derives requirements for such a model. The core of the article is the presentation of a model for analysing narrative transmission. This model aims to bridge the gap between specialist narratological knowledge and knowledge that is relevant for promoting an understanding of literary texts in educational contexts. The model is characterised by the combination of three features: (1) hierarchisation of categories in narrative text analysis (who narrates? –> how? –> what?), (2) use of questions, rather than abstract terms, to stimulate understanding, (3) linking of the three levels of analysis: How does the narrative transmission influence our understanding of what is narrated