Ruhr-Universität Bochum (RUB): Open Journal Systems
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Traduir del català a l\u27alemany: una història en construcció (1583–2024)
No full textThis introductory paper opens the monographic issue on literary translation in Catalan and German. On the one hand, it provides a chronological overview of the works originally written in Catalan that have been published in Austria, Germany and Switzerland from 1583 to the present day. On the other hand, it gives an account of the eight articles of which the issue consists and describes their content, methodology and most outstanding results.This introductory paper opens the monographic issue on literary translation in Catalan and German. On the one hand, it provides a chronological overview of the works originally written in Catalan that have been published in Austria, Germany and Switzerland from 1583 to the present day. On the other hand, it gives an account of the eight articles of which the issue consists and describes their content, methodology and most outstanding results
Activitats verbals de la construcció d\u27autoimatge en el discurs parlamentari
Full text linkIn the present work, an analysis of self-image activities is carried out within the framework of parliamentary language, which is also intended to reflect the values that politicians defend in order to constitute or reaffirm their social image. In addition, the study analyses the possible neutral, polite or impolite social effects of self-image activities on the interlocutors or recipients of the interventions. It is assumed that the studied interventions involve strategic behaviour, they have a goal which is, among other things, to enhance the image of the speaker and thereby gain the favour of multiple audiences. The theoretical framework is based on the concept of image activities (Hernández Flores, 2013), considering the social image from the basic categories of autonomy and affiliation (Bravo, 1999) with its individual and group realizations (Bravo, 1999, 2002). The analysis carried out shows that the most productive strategy of the self-image activity is that of group affiliation whose social effect is usually neutral, which means that the self-image of the own group presents the main objective of the strategy.In the present work, an analysis of self-image activities is carried out within the framework of parliamentary language, which is also intended to reflect the values that politicians defend in order to constitute or reaffirm their social image. In addition, the study analyses the possible neutral, polite or impolite social effects of self-image activities on the interlocutors or recipients of the interventions. It is assumed that the studied interventions involve strategic behaviour, they have a goal which is, among other things, to enhance the image of the speaker and thereby gain the favour of multiple audiences. The theoretical framework is based on the concept of image activities (Hernández Flores, 2013), considering the social image from the basic categories of autonomy and affiliation (Bravo, 1999) with its individual and group realizations (Bravo, 1999, 2002). The analysis carried out shows that the most productive strategy of the self-image activity is that of group affiliation whose social effect is usually neutral, which means that the self-image of the own group presents the main objective of the strategy
Chosen-IV Algebraic Attack on Randomized Ciphers FASTA and HERA
No full textFully homomorphic encryption (FHE) enables computation on encrypted data without decryption, providing strong guarantees for privacy-preserving applications. However, its practicality heavily depends on the efficiency of the underlying cryptographic primitives. To this end, FHE-friendly symmetric ciphers have been designed to achieve a balance between security and homomorphic efficiency. Among them, FASTA (a variant of Rasta) and HERA are two FHE-friendly symmetric-key primitives proposed at CT-RSA 2022 and ASIACRYPT 2021, respectively. Previous cryptanalytic results of FASTA and HERA were achieved by peeling off the last nonlinear layer. In this paper, we present an improved algebraic cryptanalysis of FASTA by exploiting structural properties of its affine layers through chosen-IV algebraic attacks. We demonstrate that both the first and last nonlinear layers of FASTA can be removed, which significantly reduces the algebraic degree of the resulting system. As a result, we achieve the first key-recovery attack on 4-round FASTA, with time complexity about 2118.8, memory complexity 294.2, and data complexity 234.1, improving the best attack by 1 round. Overall, our findings reveal exploitable algebraic weaknesses in the affine layer of FASTA. For HERA, our refined chosen-IV algebraic attack based on the eXtended Linearization (XL) algorithm significantly enlarges the feasible parameter range, enabling attacks on prime moduli that were previously considered out of reach. This is mainly because the integration of the XL algorithm further decreases the number of keystream words required during the online phase of the chosen-IV algebraic attack, thus reducing the cost of its offline phase, i.e., a better tradeoff between the offline and online complexity can be achieved in our improved attack. This highlights the central role of the XL algorithm in enabling efficient algebraic attacks on FHE-friendly symmetric ciphers
Phenomenal structure: What is it and what is it for?
No full textCore theoretical and methodological commitments for a structuralist science of phenomenal experience are articulated in sufficient detail to define a substantive, actionable research program. I argue that phenomenal experience is characterized by geometric, group-theoretic, and dynamic structure. Intuitively, these structures correspond to phenomenal quality spaces, perceptual constancies, and the perceived valence or affordance of possibilities for action. These structures instantiate distinctively phenomenal features of experience: geometrical structure functions as a precondition for meaning; group-theoretic structure induces a distinction between subject and object; and dynamical structure imbues the objective world with value and meaning. The methodological imperative of a structuralist science of consciousness is to establish isomorphisms, or structure-preserving maps, between these phenomenal structures and corresponding neural and physical structures. Progress in this research program is driven by iterative refinement and de-idealization of phenomenal, neural, and physical models in the pursuit of more sophisticated and precise isomorphisms between them. This project succeeds in targeting first-personal phenomenal experience by rendering structural relations between phenomenal experiences behaviorally manifest, and thereby exposing them to intersubjective comparisons using third-personal methods.
The incommensurability problem: A critique of phenomenal structuralism
No full textPhenomenal structuralism marks a significant shift in the study of consciousness, emphasizing the relational properties of experiential qualities rather than their intrinsic properties. This approach highlights how subjective qualities are organized and related, proposing that these structural relationships individuate such qualities within a multidimensional space. This paper focuses on the core tenets of phenomenal structuralism, particularly its commitment to holism, and the challenges it poses for comparing experiences both between and within subjects. These challenges cast serious doubt on whether similar qualitative experiences are possible across different individuals or over time. This issue is especially concerning in cases like pain, which has important ethical implications. While phenomenal structuralism successfully illuminates the relational nature of qualities, it fails to adequately account for shared aspects of qualitative experience and the possibility that different sets of qualities might lead to the same discriminations. The paper concludes by considering alternative approaches, such as representationalism, which might preserve the strengths of phenomenal structuralism without its problematic consequences. This critique calls for further investigation into how qualitative experiences can be rigorously understood without invoking intrinsic properties in mental states
Sprachliche Bedürfnisse, akademische Ausrichtung oder beides? Die Wahrnehmung der Bedürfnisse internationaler Studierender in EME-Masterstudiengängen durch Fachdozent*innen
No full textDer Wechsel zu Englisch als Unterrichtssprache an Hochschulen in Deutschland verfolgt unter anderem das Ziel, die sprachlichen Hürden zum Studium für internationale Studierende zu verringern. Doch trotz Englisch als Kommunikationssprache berichten Lehrende in englischsprachigen Studiengängen von Kommunikationsschwierigkeiten mit internationalen Studierenden. Um eine geeignete Unterstützungsmaßnahme für diese Zielgruppe zu entwickeln, wurde eine Befragung von Lehrenden in englischsprachigen Studiengängen durch das Sprachenzentrum der Technischen Universität Darmstadt durchgeführt. Die Onlinebefragung zielte darauf ab, die Wahrnehmung Lehrender zum sprachlichen sowie akademischen Qualifizierungsbedarf bei internationalen Studierenden zu eruieren und somit Interventionsschwerpunkte festzulegen. Die Aussagen der Lehrende zeigen, dass die Handlungskompetenz internationaler Studierende in Englisch im Rahmen des Masterstudiums teilweise nicht den Erwartungen der Lehrenden entspricht, vor allem im Bereich Sprechen und Schreiben. Sie machen aber auch deutlich, dass gelungene Kommunikation im Studium stark mit soziokulturellem Wissen über den deutschen Hochschulkontext zusammenhängt. Sprachliche Interventionen für diese Zielgruppe sollten demnach idealerweise sowohl Sprache als auch akademisch-kulturelle Orientierung zusammen denken.One of the aims of switching to English as the language of instruction at universities in Germany is to reduce the language barriers to studying for international students. However, despite English being the language of communication, teachers in English-language degree programs report communication difficulties with international students. In order to develop appropriate support measures for this target group, the Language Center at Darmstadt Technical University conducted a survey of teachers in English-language degree programs. The online survey aimed to determine teachers\u27 perceptions of the linguistic and academic qualification needs of international students, and thus to identify areas for intervention. The statements made by the teachers show that the English language skills of international students in master\u27s programs sometimes do not meet the expectations of the teachers, especially in the areas of speaking and writing. However, they also make it clear that successful communication during studies is strongly related to sociocultural knowledge about the German university context. Language interventions for this target group should therefore ideally combine language and academic-cultural orientation.
 
AutoDiVer: Automatically Verifying Differential Characteristics and Learning Key Conditions
Full text linkDifferential cryptanalysis is one of the main methods of cryptanalysis and has been applied to a wide range of ciphers. While it is very successful, it also relies on certain assumptions that do not necessarily hold in practice. One of these is the hypothesis of stochastic equivalence, which states that the probability of a differential characteristic behaves similarly for all keys. Several works have demonstrated examples where this hypothesis is violated, impacting the attack complexity and sometimes even invalidating the investigated prior attacks. Nevertheless, the hypothesis is still typically taken for granted. In this work, we propose AutoDiVer, an automatic tool that allows to thoroughly verify differential characteristics. First, the tool supports calculating the expected probability of differential characteristics while considering the key schedule of the cipher. Second, the tool supports estimating the size of the space of keys for which the characteristic permits valid pairs, and deducing conditions for these keys. AutoDiVer implements a custom SAT modeling approach and takes advantage of a combination of features of advanced SAT solvers, including approximate model counting and clause learning. To show applicability to many different kinds of block ciphers like strongly aligned, weakly aligned, and ARX ciphers, we apply AutoDiVer to GIFT, PRESENT, RECTANGLE, SKINNY, Midori, WARP, SPECK, and SPEEDY
Extending the Quasidifferential Framework: From Fixed-Key to Expected Differential Probability
Full text linkBeyne and Rijmen proposed in 2022 a systematic and generic framework to study the fixed-key probability of differential characteristics. One of the main challenges for implementing this framework is the ability to efficiently handle very large quasidifferential transition matrices (QDTMs) for big (e.g. 8-bit) S-boxes. Our first contribution is a new MILP model capable of efficiently representing such matrices, by exploiting the inherent block structure of these objects. We then propose two extensions to the original framework. First, we demonstrate how to adapt the framework to the related-key setting. Next, we present a novel approach to compute the average expected probability of a differential characteristic that takes the key schedule into account. This method, applicable to both linear and non-linear key schedules, works in both the single-key and related-key settings. Furthermore, it provides a faster way to verify the validity of characteristics compared to computing the fixed-key probability. Using these extensions and our MILP model, we analyze various (related-key) differential characteristics from the literature. First, we prove the validity of several optimal related-key differential characteristics of AES. Next, we show that this approach permits to obtain more precise results than methods relying on key constraints for SKINNY. Finally, we examine the validity of a differential distinguisher used in two differential meet-in-the-middle attacks on SKINNY-128, demonstrating that its probability is significantly higher than initially estimated
Improved Quantum Linear Attacks and Application to CAST
Full text linkThis paper studies quantum linear key-recovery attacks on block ciphers. The first such attacks were last-rounds attacks proposed by Kaplan et al. (ToSC 2016), which combine a linear distinguisher with a guess of a partial key. However, the most efficient classical attacks use the framework proposed by Collard et al. (ICISC 2007), which computes experimental correlations using the Fast Walsh-Hadamard Transform. Recently, Schrottenloher (CRYPTO 2023) proposed a quantum version of this technique, in which one uses the available data to create a quantum correlation state, which is a superposition of subkey candidates where the amplitudes are the corresponding correlations. A limitation is that the good subkey is not marked in this state, and cannot be found easily.In this paper, we combine the correlation state with another distinguisher. From here, we can use Amplitude Amplification to recover the right key. We apply this idea to Feistel ciphers and exemplify different attack strategies on LOKI91 before applying our idea on the CAST-128 and CAST-256 ciphers. We demonstrate the approach with two kinds of distinguishers, quantum distinguishers based on Simon’s algorithm and linear distinguishers. The resulting attacks outperform the previous Grover-meet-Simon attacks
TFHE Gets Real: an Efficient and Flexible Homomorphic Floating-Point Arithmetic
Full text linkFloating-point arithmetic plays a central role in computer science and is used in various domains where precision and computational scale are essential. One notable application is in machine learning, where Fully Homomorphic Encryption (FHE) can play a crucial role in safeguarding user privacy. In this paper, we focus on TFHE and develop novel homomorphic operators designed to enable the construction of precise and adaptable homomorphic floating-point operations. Integrating floating-point arithmetic within the context of FHE is particularly challenging due to constraints such as small message space and the lack of information during computation. Despite these challenges, we were able to determine parameters for common precisions (e.g., 32-bit, 64-bit) and achieve remarkable computational speeds, with 32-bit floating-point additions completing in 2.5 seconds and multiplications in approximately 1 second in a multi-threaded environment. These metrics provide empirical evidence of the efficiency and practicality of our proposed methods, which significantly outperform previous efforts. Our results demonstrate a significant advancement in the practical application of FHE, making it more viable for real-world scenarios and bridging the gap between theoretical encryption techniques and practical usability