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The Imperial Gaze: Practices, Representations, and Identities in the Visual Archive
No full textpeer reviewed(1) The first part of this book presents five texts written by scholars from diverse disciplinary backgrounds which share a focus on traveling and/or tourism as a means of actively constructing identity and otherness in colonial contexts. The chapters analyze travel guides, albums, diaries, postcards, the press, film, and television as powerful media shaping empire, colonial culture, and (foreign) territories, where the visual takes center stage. Images were used as a means of domination and objectification, and served as conveyers of familiarity, identity, and otherness across geographies and what were perceived as cultural borders. It was not only the male but also the female gaze that was engaged in contrasting notions of Western civilization against untamed colonial landscapes, geographies and cultures. The different chapters address how (home) audiences were instructed on the way in which they should see, experience, and interpret the colonial project, its powerful interventions and hierarchical structure. (2) The second part of the book focuses on the gender of imperial imagery. Imagery of the female body – a powerful site of colonial and imperial conquest – gives rise to a collision between the cultural norms and practices of the colonized with the normalizing and stereotyped cultural codes of metropoles. The choices of the image taker, and the intent behind the taking of the image, lie principally with the colonizer. This interaction was often carried out by male stakeholders, privileged because of their power, yet their image taking unwittingly undoing the white male language of empire when viewers, as recipients, saw in these images disconnections around gender and culture – and even imperial malignancies created by the imposition of Western religion. Imposing the paradigm of gender on the imagery generated by empire, the chapters in this part of the book provide important perspectives about the intent and imperatives of empire. (3) The essays that make up the third part of this book deal with the imperial archive. Jeffrey Wallen (2023) recently described the last thirty years as “the era of the archive”: not only has there been a dramatic increase in the collection of documents and the establishment of archives, but the archive itself is now “one of the central topics of thought throughout the humanities,” appealing to a desire “to come in contact with the material of history” and, at the conceptual level, “to engage with the archive itself, both as an institution and as a constitutive and transformative force.” In some ways Wallen was echoing an earlier lecture by Stuart Hall (2025) in The Missing Chapter where he outlined his view that archives involve engaging in “a conversation between the past and the present”; they are a place of “activity and engagement” which must provoke people to think differently and ask new questions – otherwise they are “completely dead.” (4) Part four is dedicated to imperial looking and storytelling. Imperial visualities produced and were produced along narratives that told stories about the colonial and postcolonial experience. If “visual technologies and practices frequently underwrote colonial governance and power” (Ramaswamy 2024) , they did so within broader worldviews that gave meaning to the imperial experience, in both the metropole and the colonies. Most historiographies have not paid sufficient attention to the nexuses between empire and vision and have remained “dominated by the hegemony of the word and the tyranny of the textual archive” (ibid.). The focus on images should not neglect to consider how they were supplemented by histories about the self, the other, and the world. The chapters in this section analyze narratives about progress, humankind, war, and subalternity that were constitutive of the imperial gaze – some of them supposedly well-intentioned, some of them unabashedly exploitative, but in all cases never neutral in relation to the imperial regimes in which they were inscribed. (5) Part five of this volume concerns the journeys that visual studies can undertake over time – untrammeled by the written text and today’s strong epistemological boundaries when writing about colonial “others.” This is particularly in evidence when it comes to First Nations peoples of Australia. Images of them can convey false colonial impressions of “the other,” even when taken by the most sympathetic image-taker in past eras. First Nation Australians are often conveyed as “primitive,” with no written language and little recoverable “culture,” in images that are inescapably complicit with the eugenics of empire – unlike Brahmins in India, who are associated with their deep Sanskrit-based knowledge and written language. However, reconsidering these same images of First Australians through a contemporary lens, using separate theorizations, captures new meaning – reframed and contextualized to verify deeper knowledge garnered by new sociological, anthropological, and even psychological vistas that better, albeit still imperfectly, understand the consequences of unjust colonial dispossession. This final section reveals other dimensions as well. For people of color, “turning the camera on oneself” can be a means of reclaiming control of their identity. Although the camera and film might be used without any initial intention to convey meaning, yet meaning is recoverable in unintended ways by later generations when looking at these same images. Powerful revisions in messaging are also possible by placing images in a museum as part of new thematic exhibitions
PaCo: Bootstrapping for CKKS via Partial CoeffToSlot
Full text linkpeer reviewedWe introduce PaCo, a novel and efficient bootstrapping procedure for the CKKS homomorphic encryption scheme, where PaCo stands for “(Bootstrapping via) Partial CoeffToSlot”. At a high level, PaCo reformulates the CKKS decryption equation in terms of blind rotations and modular additions. This reformulated decryption circuit is then evaluated homomorphically within the CKKS framework. Our approach makes use of the circle group in the complex plane to simulate modular additions via complex multiplication, and utilizes alternative polynomial ring structures to support blind rotations. These ring structures are enabled by a variant of the CoeffToSlot operation, which we call a partial CoeffToSlot. This yields a new bootstrapping approach within CKKS, achieving a computational complexity which is logarithmic in the number of complex slots. We further introduce a parallelized variant that enables bootstrapping over all CKKS slots with enhanced throughput, highlighting PaCo’s suitability for practical and large-scale homomorphic applications. In addition to the bootstrapping technique itself, we develop several supporting tools — particularly in the context of bit-reversing and alternative ring structures for CKKS — which can be of independent interest to the community. Finally, a proof-of-concept implementation confirms that PaCo achieves performance competitive with state-of-the-art methods for CKKS bootstrapping
Optimized sparse 2D antenna array design via beampattern matching
No full textpeer reviewedEmerging millimeter-wave (mmWave) MIMO radars combine the benefits of large bandwidth available at mmWave frequencies with the spatial diversity provided by MIMO architectures, significantly enhancing radar capabilities for automotive, surveillance, and imaging applications. However, deploying large numbers of antennas and transceivers at these high frequencies substantially increases chip complexity and hardware costs. In this paper, we address the design of sparse two-dimensional (2D) antenna arrays that retain the desirable beampattern characteristics of fully populated arrays – namely, narrow mainlobes and low sidelobes – while significantly reducing the required number of antenna elements. We formulate the sparse array design problem as a beampattern matching optimization, which selects optimal subsets of transmit and receive antenna positions from an initial dense grid. To efficiently solve this challenging nonconvex optimization problem, we introduce an iterative algorithm combining Majorization–Minimization (MM) and Alternating Optimization (AO) techniques. We provide theoretical guarantees for convergence to at least a local optimum. Additionally, we propose a weighting vector optimization step to further enhance sidelobe suppression. Numerical simulations confirm that the proposed method maintains angular resolution and Sidelobe Levels (SLLs) comparable to those of full arrays, while substantially reducing hardware complexity and cost. Performance comparisons against existing methods demonstrate notable improvements in sidelobe suppression and computational efficiency without compromising processing gain
LunarLeaper—A mission concept to explore the lunar subsurface with a small-scale legged robot
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Multimodal Learning for Operational Risk Detection in Delivery Route Planning
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Privacy evaluation of the European Digital Identity Wallet's Architecture and Reference Framework
Full text linkpeer reviewedDigital identity wallets promise significant advancements in digital identity management by offering users a high degree of convenience, security, and control over their data disclosure. However, there is also criticism regarding their privacy guarantees, especially when used in regulated use cases that require high levels of assurance on the correctness and binding of a legal identity. In this paper, we present a comprehensive privacy model and analysis of one of the most prominent digital wallets – the European Digital Identity Wallet (EUDIW) – as specified by the Architecture and Reference Framework (ARF) and the eIDAS 2.0 regulation. We employ a suite of qualitative privacy risk assessment methods to systematically map and evaluate information flows in three key use cases. Our analysis identifies multiple privacy risks – including linkability, identifiability, and excessive attribute data disclosure – and reveals that although the ARF is designed to comply with privacy-by-design principles, inherent design choices, such as the reliance on SD-JWT and mDOC data formats, as well as the concept of a Wallet Unit Attestation (WUA), retain risks to user privacy. Building on our findings, we then highlight how advanced Privacy-Enhancing Technologies (PETs), such as (general-purpose) Zero-Knowledge Proofs (ZKPs), can reduce or mitigate some of these risks
From at Least n/3 to at Most 3n: Correcting the Algebraic Immunity of the Hidden Weight Bit Function: Algebraic Immunity Upper Bounds on Weightwise Degree-d Functions and Their Implications
Full text linkpeer reviewedWeightwise degree-d (WWdd) functions are Boolean functions that, on each set of fixed Hamming weight, coincide with a function of degree at most d. They generalize both symmetric functions and the Hidden Weight Bit Function (HWBF), which has been studied in cryptography for its favorable properties. In this work, we establish a general upper bound on the algebraic immunity of such functions, a key security parameter against algebraic attacks on stream ciphers like filtered Linear Feedback Shift Registers (LFSRs). We construct explicit low-degree annihilators for WWdd functions with small d, and show how to generalize these constructions. As an application, we prove that the algebraic immunity of the HWBF is upper bounded by 3n disproving a result from 2011 that claimed a lower bound of n/3. We then apply our technique to several generalizations of the HWBF proposed since 2021 for homomorphically friendly constructions and LFSR-based ciphers, refining or refuting results from six prior works
Cleaning Maintenance Logs with LLM Agents for Improved Predictive Maintenance
Full text linkpeer reviewedEconomic constraints, limited availability of datasets for reproducibility
and shortages of specialized expertise have long
been recognized as key challenges to the adoption and advancement
of predictive maintenance (PdM) in the automotive
sector. Recent progress in large language models (LLMs)
presents an opportunity to overcome these barriers and speed
up the transition of PdM from research to industrial practice.
Under these conditions, we explore the potential of LLMbased
agents to support PdM cleaning pipelines. Specifically,
we focus on maintenance logs, a critical data source
for training well-performing machine learning (ML) models,
but one often affected by errors such as typos, missing
fields, near-duplicate entries, and incorrect dates. We evaluate
LLM agents on cleaning tasks involving six distinct types
of noise. Our findings show that LLMs are effective at handling
generic cleaning tasks and offer a promising foundation
for future industrial applications. While domain-specific errors
remain challenging, these results highlight the potential
for further improvements through specialized training and enhanced
agentic capabilities
Fuel-aware autonomous docking using RL-augmented MPC rewards for on-orbit refueling
No full textpeer reviewedThe operational lifespan of satellites is constrained by finite fuel reserves, limiting their maneuverability and mission duration. On-orbit refueling offers a transformative solution, extending satellite functionality, reducing costs, and enhancing sustainability. However, the precise execution of docking maneuvers remains a critical challenge, exacerbated by fuel sloshing effects in microgravity, which introduce unpredictable disturbances. This study proposes an integrated control framework combining Model Predictive Control (MPC) and Reinforcement Learning (RL) to ensure safe and efficient docking under these dynamic conditions. Initially, a Proximal Policy Optimization (PPO)-based RL control strategy is introduced, leveraging MPC for trajectory optimization. To further enhance adaptability in highly dynamic environments, Soft Actor-Critic (SAC) is incorporated, offering superior sample efficiency and robustness against stochastic disturbances. The proposed SAC-MPC framework effectively mitigates fuel sloshing effects by balancing computational efficiency with predictive accuracy. Experimental validation is conducted in the Zero-G Lab, emulating control scenarios with 3-DoF floating platforms, while high-fidelity numerical simulations extend the study to 6-DoF dynamics with realistic sloshing behavior modeled using OpenFOAM. Comparative results demonstrate that SAC-MPC outperforms conventional RL and MPC-based methods in docking success rate, precision, and control effort. This research establishes a robust foundation for autonomous satellite docking, contributing to the viability of on-orbit refueling missions and the future of sustainable space operations
