Ruhr-Universität Bochum (RUB): Open Journal Systems
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Country Report: United Kingdom (England)
Get PDFAs a result of the acts of devolution in Scotland, Wales, and Northern Ireland, the education systems of each nation (plus England)tea are different. Differences may pertain to the age students start following the national curriculum, what the national curriculum includes, public exam bodies, and ages of compulsory school attendance. As such, this country report will focus on philosophy in schools in England. Isolating data solely to England, however, will not always be possible, for example concerning the numbers of students taking A Level Philosophy which is taken in all nations
TPUXtract: An Exhaustive Hyperparameter Extraction Framework
No full textModel stealing attacks on AI/ML devices undermine intellectual property rights, compromise the competitive advantage of the original model developers, and potentially expose sensitive data embedded in the model’s behavior to unauthorized parties. While previous research works have demonstrated successful side-channelbased model recovery in embedded microcontrollers and FPGA-based accelerators, the exploration of attacks on commercial ML accelerators remains largely unexplored. Moreover, prior side-channel attacks fail when they encounter previously unknown models. This paper demonstrates the first successful model extraction attack on the Google Edge Tensor Processing Unit (TPU), an off-the-shelf ML accelerator. Specifically, we show a hyperparameter stealing attack that can extract all layer configurations including the layer type, number of nodes, kernel/filter sizes, number of filters, strides, padding, and activation function. Most notably, our attack is the first comprehensive attack that can extract previously unseen models. This is achieved through an online template-building approach instead of a pre-trained ML-based approach used in prior works. Our results on a black-box Google Edge TPU evaluation show that, through obtained electromagnetic traces, our proposed framework can achieve 99.91% accuracy, making it the most accurate one to date. Our findings indicate that attackers can successfully extract various types of models on a black-box commercial TPU with utmost detail and call for countermeasures
Multiplying Polynomials without Powerful Multiplication Instructions
No full textWe improve the performance of lattice-based cryptosystems Dilithium on Cortex-M3 with expensive multiplications. Our contribution is two-fold: (i) We generalize Barrett multiplication and show that the resulting shape-independent modular multiplication performs comparably to long multiplication on some platforms without special hardware when precomputation is free. We call a modular multiplication “shape-independent” if its correctness and efficiency depend only on the magnitude of moduli and not the shapes of the moduli. This was unknown in the literature even though modular multiplication has been studied for more than 40 years. In the literature, shape-independent modular multiplications often perform several times slower than long multiplications even if we ignore the cost of the precomputation. (ii) We show that polynomial multiplications based on Nussbaumer fast Fourier transform and Toom–Cook over Z2k perform the best when modular multiplications are expensive and k is not very close to the arithmetic precision.For practical evaluation, we implement assembly programs for the polynomial arithmetic used in the digital signature Dilithium on Cortex-M3. For the modular multiplications in Dilithium, our generalized Barrett multiplications are 1.92 times faster than the state-of-the-art assembly-optimized Montgomery multiplications, leading to 1.38−1.51 times faster Dilithium NTT/iNTT. Along with the improvement in accumulating products, the core polynomial arithmetic matrix-vector multiplications are 1.71−1.77 times faster. We further apply the FFT-based polynomial multiplications over Z2k to the challenge polynomial multiplication ct0, leading to 1.31 times faster computation for ct0.We additionally apply the ideas to Saber on Cortex-M3 and demonstrate their improvement to Dilithium and Saber on our 8-bit AVR environment. For Saber on Cortex-M3, we show that matrix-vector multiplications with FFT-based polynomial multiplications over Z2k are 1.42−1.46 faster than the ones with NTT-based polynomial multiplications over NTT-friendly coefficient rings. When moving to a platform with smaller arithmetic precision, such as 8-bit AVR, we improve the matrix-vector multiplication of Dilithium with our Barrett-based NTT/iNTT by a factor of 1.87−1.89. As for Saber on our 8-bit AVR environment, we show that matrixvector multiplications with NTT-based polynomial multiplications over NTT-friendly coefficient rings are faster than polynomial multiplications over Z2k due to the large k in Saber
“We Were Striving For Our Revolution” — Navigating Harms in the Pursuit of Change
Get PDFThe death of Zhina-Mahsa Amini on September 16, 2022 ignited widespread protests against the oppression in various parts of Iran. The response from the Islamic Republic (IR) to these protests has been characterised by extreme violence since their inception in September 2022. This raises the question of how and why individuals continue to protest and resist such oppression despite facing them persistently. To explore this question, we conducted qualitative interviews with individuals who participated in the protests of 2022–2023. The research focused on the protesters’ perceptions and their strategies for coping with the oppression they faced. We used the evolving HARM-concept to investigate the profound consequences of suffering on the protesters’ ability to act. The evaluation of the interviews revealed that community-feeling played a crucial role in their decision to resist. The interviewees reported various forms of everyday resistance and how they dealt with the ongoing oppression. It turned out that community-feeling could influence perceptions of HARM and expand the possibilities of dealing with injury. Additionally, factors such as mental endurance and vulnerability appeared to change individuals’ perceptions and handling of injury
Warrior, Poet and Artist: Sixteenth-Century Ottoman Naval Battles through the Eyes of Nigârî
No full textNigârî was a significant painter of miniatures in the sixteenth century, known primarily for his portraits of Sultan Selim II and Barbaros Hayreddin Pasha (Barbarossa), which brought influences from Western-style portraiture to the Ottoman tradition of miniature painting. Since he was a sociable and cheerful person, he was popular in many assemblies, and even became Prince Selim’s (Later Sultan Selim II) boon companion. In addition, Nigârî was a long-serving captain in the Ottoman navy, fighting in many sea battles and proving his usefulness as a soldier. Moreover, Nigârî was a poet, and, while some of his shorter poetry can be seen written beneath his paintings, his major literary work is the heroic poem in praise of Grand Admiral Sinan Pasha, Ghazavat-i Sinan Pasha (Holy Wars of Sinan Pasha). In this book, Nigârî tells of the naval battles that occurred under Admiral Sinan Pasha which he witnessed personally. Among them were the expeditions to Messina and Malta, the conquest of Tripoli, and the defeat of the Crusader fleet under the command of Andrea Doria. A great deal of detail about these expeditions and battles is included in the work that is not found elsewhere. There are many subjects mentioned by the poet, including the places they stopped at on their voyage, the people they travelled with, the number of navy ships, and the admiral’s consultations with the sailors. Furthermore, it includes elements of military and state traditions as well as social life. Therefore, Nigârî’s work holds significant value for literature as well as maritime, social, and cultural history, and carries the potential to serve as a valuable supplementary source in these fields. This paper is organised into two sections, the first of which is an overview of Nigârî’s life and major works. The second section discusses Nigârî’s Ghazavat-i Sinan Pasha, notable for its portrayal of naval battles firsthand and its insight into the broader sociocultural intersections of military history
Chosen-Prefix Collisions on AES-like Hashing
No full textChosen-prefix collision (CPC) attack was first presented by Stevens, Lenstra and de Weger on MD5 at Eurocrypt 2007. A CPC attack finds a collision for any two chosen prefixes, which is a stronger variant of collision attack. CPCs are naturally harder to construct but have larger practical impact than (identical-prefix) collisions, as seen from the series of previous works on MD5 by Stevens et al. and SHA-1 by Leurent and Peyrin. Despite its significance, the resistance of CPC attacks has not been studied on AES-like hashing.In this work, we explore CPC attacks on AES-like hashing following the framework practiced on MD5 and SHA-1. Instead of the message modification technique developed for MD-SHA family, we opt for related-key rebound attack to construct collisions for AES-like hashing in view of its effectiveness. We also note that the CPC attack framework can be exploited to convert a specific class of one-block free-start collisions into two-block collisions, which sheds light on the importance of free-start collisions. As a result, we present the first CPC attacks on reduced Whirlpool, Saturnin-hash and AES-MMO/MP in classic and quantum settings, and extend the collision attack on Saturnin-hash from 5 to 6 rounds in the classic setting. As an independent contribution, we improve the memoryless algorithm of solving 3-round inbound phase by Hosoyamada and Sasaki at Eurocrpyt 2020, which leads to improved quantum attacks on Whirlpool. Notably, we find the first 6-round memoryless quantum collision attack on Whirlpool better than generic CNS collision finding algorithm when exponential-size qRAM is not available but exponential-size classic memory is available
GPU Acceleration for FHEW/TFHE Bootstrapping
No full textFully Homomorphic Encryption (FHE) allows computations to be performed directly on encrypted data without decryption. Despite its great theoretical potential, the computational overhead remains a major obstacle for practical applications. To address this challenge, hardware acceleration has emerged as a promising approach, aiming to achieve real-time computation across a wider range of scenarios. In line with this, our research focuses on designing and implementing a Graphic Processing Unit (GPU)-based accelerator for the third generation FHEW/TFHE bootstrapping scheme, which features smaller parameters and bootstrapping keys particularly suitable for GPU architectures compared to the other generations.In summary, our accelerator offers improved efficiency, scalability, and flexibility for extensions, e.g., functional bootstrapping (Liu et al., Asiacrypt 2022), compared to current state-of-the-art solutions. We evaluate our implementation and demonstrate substantial speedup in the single-GPU setting, our bootstrapping achieves an 18x - 20x speedup compared to a 64-thread server-class CPU; by using 8 GPUs, the throughput can be further improved by 7x compared to the single-GPU implementation, confirming the scalability of our design. Furthermore, compared to the SoTA GPU solution TFHE-rs, we achieve a maximum speedup of 1.69x in AND gate evaluation. Finally, we benchmark several private machine learning applications, showing real-time solutions for (1) encrypted neural network inference for MNIST in 0.04 seconds per image, which is the fastest implementation to our knowledge.(2) private decision trees in 0.38 seconds for Iris dataset, where as prior 16 cores CPU implementation (Lu et al., IEEE S&P 2021) required 1.87 seconds; These results highlight the effectiveness and efficiency of our GPU-acceleration in real-world applications.As a technical highlight, we design a novel parallelization strategy tailored for FHEW/TFHE bootstrapping, allowing an automated optimization that partitions bootstrapping into multiple GPU thread blocks. This is necessary for FHEW/TFHE bootstrapping with scalable parameters, where the whole bootstrapping process may not fit into a single thread block. With this, our accelerator can support a broader range of parameters, making it ideal for upcoming privacy-preserving applications
Minimal states of awareness across sleep and wakefulness: A multidimensional framework to guide scientific research
No full textI introduce a novel multidimensional framework tailored to investigate a set of phenomena that might appear intractable and render them amenable to scientific inquiry. In particular, I focus on examining altered states of consciousness that appear to the experiencing subject as “contentless” or “objectless” states in some form, either by having disrupted or reduced content of awareness, or content that appears as missing altogether. By drawing on empirical research, I propose a cluster of phenomenological dimensions aimed at enhancing our understanding of this group of experiences of minimal awareness, including Richness of the Content, Bodily-Awareness, Passage of Time, Attentional Focus, and Self-Revelation. The result is a robust framework that provides precise scientific terminology, facilitating its operationalisation and adaptability for future empirical work. I show the explanatory power of this framework through a case study of the state of clear light sleep—a state widely reported by Indo-Tibetan Buddhist traditions as an instance of pure awareness during sleep, a state of consciousness-as-such. This rare phenomenon has gained increasing attention in contemporary analytic philosophy of mind for the study of the nature of consciousness. However, we still lack consensus on its characterisation and potential identity with other associated states. I end the paper by illustrating how the state of clear light sleep can be situated in relation to other associated states and more ordinary ones as regions of a multidimensional state space
Conversions to Shiʿism in Italy and Editorial Ventures
Get PDFThis article presents an in-depth analysis of two interrelated topics, namely Italians’ conversions to Shiʿism and their contribution to disseminating knowledge about Twelver Shiʿism in Italy. Employing a combination of historical and sociological methods, the article explores the underlying motivations driving this religious mobility, with a particular focus on the influence of Traditionalist authors such as René Guénon and Julius Evola and the Iranian Revolution on the digital and paper publications of converts. Moreover, the paper investigates the converts’ proclivity for editorial initiatives and social visibility, which can be attributed to their penchant for social engagement and political activism. To conduct this investigation, semi-structured interviews, literature analysis, and historical sources were adopted. This research establishes a strong correlation between the reasons for conversion and the portrayal of Shiʿism in the converts’ literary works. In summary, the distinct characteristics of Italian Shiʿism are intricately intertwined with the factors influencing conversion to this religion
Intuition, Rebellion and Tradition: First Encounter Narratives in Mexican Neopaganism
Get PDFNeopagans in Mexico City started to communitise only about 20 years ago. An initial analysis of related interview material shows that the narratives they develop about their first contact with neopagan content and their access to the field are framed as a conversion-like process, often connoted as a home-coming or a rebellion against predominant Catholicism. Both narratives are usually mixed with a notion of intuition that led to their further involvement in neopagan groups. Nevertheless, Mexican “folk magic” and vernacular healing traditions, Afro-American religions, and the flourishing esoteric scene in the Mexican capital are already offering links to beliefs and practices that are common in neopaganism, like ritualised ways to interact with transcendent entities, magic, and ideas of an “otherworld”.
This raises various questions related to the underlying dynamics, in brief: how do heterogeneous sociohistorical situations influence emerging religious fields like the neopagan one in the Mexican capital, and how do these interactions shape personal religious transformation processes in the wider context of glocalisation, transcultural dynamics, digitalisation and the diversification of the religious field overall? In the light of Adler’s (1979) influential concept of home-coming and Luhrmann’s (1989) theory of the interpretative drift, it remains clear that becoming neopagan is rarely understood as a conversion, and therefore the two contested theoretical approaches are discussed critically and in relation to conversion. Using a grounded theory approach and thus emphasising the emic perspectives of my interviewees, I show how they construct their first encounter narratives and frame them as intuition, rebellion, or tradition, considering the underpinning sociocultural circumstances