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Spread-out percolation on transitive graphs of polynomial growth
Let be a vertex-transitive graph of superlinear polynomial growth. Given
, let be the graph on the same vertex set as , with two vertices
joined by an edge if and only if they are at graph distance at most apart
in . We show that the critical probability for Bernoulli bond
percolation on satisfies as
. This extends work of Penrose and Bollob\'as-Janson-Riordan, who
considered the case .
Our result provides an important ingredient in parallel work of
Georgakopoulos in which he introduces a new notion of dimension in groups. It
also verifies a special case of a conjecture of Easo and Hutchcroft.Comment: 35 page
Graphs for torus actions on oriented manifolds with isolated fixed points and classification in dimension 6
Let a torus act on a compact oriented manifold with isolated fixed
points, with an additional mild assumption that its isotropy submanifolds are
orientable. We associate a signed labeled multigraph encoding the fixed point
data (weights and signs at fixed points and isotropy submanifolds) of the
manifold. We study operations on and its multigraph, (self) connected sum
and blow up, etc. When the circle group acts on a 6-dimensional , we
classify such a multigraph by proving that we can convert it into the empty
graph by successively applying two types of operations. In particular, this
classifies the fixed point data of any such manifold. We prove this by showing
that for any such manifold, we can successively take equivariant connected sums
at fixed points with itself, , and 6-dimensional analogue
and of the Hirzebruch surfaces (and these with opposite orientations) to
a fixed point free action on a compact oriented 6-manifold. We also classify a
multigraph for a torus action on a 4-dimensional .Comment: Added the assumption on the orientability of isotropy submanifolds.
This paper supercedes arXiv:2108.07560; main results are new, while including
all results of the previous on
Noetherianity of twisted Zhu algebra and bimodules
In this paper we show that for a large natural class of vertex operator
algebras (VOAs) and their modules, the Zhu algebras and bimodules (and their
-twisted analogs) are Noetherian. These carry important information about
the representation theory of the VOA, and its fusion rules, and the Noetherian
property gives the potential for (non-commutative) algebro-geometric methods to
be employed in their study
Is Universal Broadband Service Impossible?
Broadband Internet service is widely expected to be the fundamental universal
service for the 21st century. But more than a decade of national and
international struggles to close the digital divide between broadband haves and
have nots suggest that reaching global universality will be a very difficult
task. This paper argues that the strong guarantees made by the current
broadband paradigm - low latency and constant availability - are unnecessary
obstacles to its adoption as an affordable and universal digital service. We
show that there is nonetheless a plausible strategy for deploying a Basic
Broadband service that does not require such guarantees and is able to offer,
at reasonable cost, almost all the critical and valuable services and
applications currently delivered over low latency broadband, synchronous
telepresence excepted.Comment: Appeared in IEEE 19th International Conference on Mobile Ad Hoc and
Smart Systems 202
Digital Twin Aided RIS Communication: Robust Beamforming and Interference Management
Reconfigurable intelligent surfaces (RISs) are envisioned to play a key role
in future wireless communication networks. However, channel estimation in
RIS-aided wireless networks is challenging due to their passive nature and the
large number of reflective elements, leading to high channel estimation
overhead. Additionally, conventional methods like beam sweeping, which do not
rely on explicit channel state information, often struggle in managing
interference in multi-user networks. In this paper, we propose a novel approach
that leverages digital twins (DTs) of the physical environments to approximate
channels using electromagnetic 3D models and ray tracing, thus relaxing the
need for channel estimation and extensive over-the-air computations in
RIS-aided wireless networks. To address the digital twins channel approximation
errors, we further refine this approach with a DT-specific robust transmission
design that reliably meets minimum desired rates. The results show that our
method secures these rates over 90% of the time, significantly outperforming
beam sweeping, which achieves these rates less than 8% of the time due to its
poor management of transmitting power and interference.Comment: Dataset and code files will be available soon on the DeepMIMIO
website: https://www.deepmimo.ne
Self-supervised Adversarial Training of Monocular Depth Estimation against Physical-World Attacks
Monocular Depth Estimation (MDE) plays a vital role in applications such as
autonomous driving. However, various attacks target MDE models, with physical
attacks posing significant threats to system security. Traditional adversarial
training methods, which require ground-truth labels, are not directly
applicable to MDE models that lack ground-truth depth. Some self-supervised
model hardening techniques (e.g., contrastive learning) overlook the domain
knowledge of MDE, resulting in suboptimal performance. In this work, we
introduce a novel self-supervised adversarial training approach for MDE models,
leveraging view synthesis without the need for ground-truth depth. We enhance
adversarial robustness against real-world attacks by incorporating
L_0-norm-bounded perturbation during training. We evaluate our method against
supervised learning-based and contrastive learning-based approaches
specifically designed for MDE. Our experiments with two representative MDE
networks demonstrate improved robustness against various adversarial attacks,
with minimal impact on benign performance.Comment: Accepted in TPAMI'24. Extended from our ICLR'23 publication
(arXiv:2301.13487). arXiv admin note: substantial text overlap with
arXiv:2301.1348
Management Decisions in Manufacturing using Causal Machine Learning -- To Rework, or not to Rework?
In this paper, we present a data-driven model for estimating optimal rework
policies in manufacturing systems. We consider a single production stage within
a multistage, lot-based system that allows for optional rework steps. While the
rework decision depends on an intermediate state of the lot and system, the
final product inspection, and thus the assessment of the actual yield, is
delayed until production is complete. Repair steps are applied uniformly to the
lot, potentially improving some of the individual items while degrading others.
The challenge is thus to balance potential yield improvement with the rework
costs incurred. Given the inherently causal nature of this decision problem, we
propose a causal model to estimate yield improvement. We apply methods from
causal machine learning, in particular double/debiased machine learning (DML)
techniques, to estimate conditional treatment effects from data and derive
policies for rework decisions. We validate our decision model using real-world
data from opto-electronic semiconductor manufacturing, achieving a yield
improvement of 2 - 3% during the color-conversion process of white
light-emitting diodes (LEDs).Comment: 30 pages, 10 figure
A Survey on Image-text Multimodal Models
With the significant advancements of Large Language Models (LLMs) in the
field of Natural Language Processing (NLP), the development of image-text
multimodal models has garnered widespread attention. Current surveys on
image-text multimodal models mainly focus on representative models or
application domains, but lack a review on how general technical models
influence the development of domain-specific models, which is crucial for
domain researchers. Based on this, this paper first reviews the technological
evolution of image-text multimodal models, from early explorations of feature
space to visual language encoding structures, and then to the latest large
model architectures. Next, from the perspective of technological evolution, we
explain how the development of general image-text multimodal technologies
promotes the progress of multimodal technologies in the biomedical field, as
well as the importance and complexity of specific datasets in the biomedical
domain. Then, centered on the tasks of image-text multimodal models, we analyze
their common components and challenges. After that, we summarize the
architecture, components, and data of general image-text multimodal models, and
introduce the applications and improvements of image-text multimodal models in
the biomedical field. Finally, we categorize the challenges faced in the
development and application of general models into external factors and
intrinsic factors, further refining them into 2 external factors and 5
intrinsic factors, and propose targeted solutions, providing guidance for
future research directions. For more details and data, please visit our GitHub
page: \url{https://github.com/i2vec/A-survey-on-image-text-multimodal-models}
Automatic Generation of Model and Data Cards: A Step Towards Responsible AI
In an era of model and data proliferation in machine learning/AI especially
marked by the rapid advancement of open-sourced technologies, there arises a
critical need for standardized consistent documentation. Our work addresses the
information incompleteness in current human-generated model and data cards. We
propose an automated generation approach using Large Language Models (LLMs).
Our key contributions include the establishment of CardBench, a comprehensive
dataset aggregated from over 4.8k model cards and 1.4k data cards, coupled with
the development of the CardGen pipeline comprising a two-step retrieval
process. Our approach exhibits enhanced completeness, objectivity, and
faithfulness in generated model and data cards, a significant step in
responsible AI documentation practices ensuring better accountability and
traceability.Comment: NAACL 2024 (Oral
Public Computing Intellectuals in the Age of AI Crisis
The belief that AI technology is on the cusp of causing a generalized social
crisis became a popular one in 2023. While there was no doubt an element of
hype and exaggeration to some of these accounts, they do reflect the fact that
there are troubling ramifications to this technology stack. This conjunction of
shared concerns about social, political, and personal futures presaged by
current developments in artificial intelligence presents the academic
discipline of computing with a renewed opportunity for self-examination and
reconfiguration. This position paper endeavors to do so in four sections. The
first explores what is at stake for computing in the narrative of an AI crisis.
The second articulates possible educational responses to this crisis and
advocates for a broader analytic focus on power relations. The third section
presents a novel characterization of academic computing's field of practice,
one which includes not only the discipline's usual instrumental forms of
practice but reflexive practice as well. This reflexive dimension integrates
both the critical and public functions of the discipline as equal intellectual
partners and a necessary component of any contemporary academic field. The
final section will advocate for a conceptual archetype--the Public Computer
Intellectual and its less conspicuous but still essential cousin, the (Almost)
Public Computer Intellectual--as a way of practically imagining the expanded
possibilities of academic practice in our discipline, one that provides both
self-critique and an outward-facing orientation towards the public good. It
will argue that the computer education research community can play a vital role
in this regard. Recommendations for pedagogical change within computing to
develop more reflexive capabilities are also provided.Comment: 28 pages, 2 table