113 research outputs found
A Low-cost and Portable Active Noise Control Unit
The objective of this research is to employ cutting-edge active noise control
methodologies in order to mitigate the noise emissions produced by electrical
appliances, such as a coffee machine. The algorithm utilized in this study is
the modified Filtered-X Least Mean Square (FXLMS) algorithm. This algorithm
aims to generate an anti-noise waveform by utilizing measurements from both the
reference microphone and the error microphone. The desired outcome of this
approach is to achieve a residual noise level of zero. The primary difficulty
lies in conducting the experiment in an open space setting, as conventional
active noise control systems are designed to function within enclosed
environments, such as closed rooms or relatively confined spaces like the
volume inside headphones. A validation test bench is established, employing the
Sigma Studio software to oversee the entire system, with the ADAU1452 digital
signal processor being chosen. This study presents an introduction to different
Active Noise Control systems and algorithms, followed by the execution of
simulations for representative techniques. Subsequently, this section provides
a comprehensive account of the procedures involved in executing the
experiments, followed by an exploration of potential avenues for further
research.Comment: A final year project report presented to the Nanyang Technological
Universit
Stop sending me messages!: The negative impact of persuasive messages on green transportation
Persuasive information and communication technology has been used to persuade people to choose fuel-efficient transportation (i.e., green transportation), for example, by sending messages to the public. Many factors may influence the effect of such messages. In this exploratory we report a social experiment, in which participants received persuasive messages from social and non-social approaches. To our surprise, results seem to show a negative impact on green transportation, meaning participants receiving the messages used less green transportation modes. This suggests that messages may not be as an effective way to persuade the public as many organizations’ practice assumes and other persuasive techniques such as real-time feedback and awareness raising techniques may be needed in causing the desired changes
Neural Architectural Backdoors
This paper asks the intriguing question: is it possible to exploit neural
architecture search (NAS) as a new attack vector to launch previously
improbable attacks? Specifically, we present EVAS, a new attack that leverages
NAS to find neural architectures with inherent backdoors and exploits such
vulnerability using input-aware triggers. Compared with existing attacks, EVAS
demonstrates many interesting properties: (i) it does not require polluting
training data or perturbing model parameters; (ii) it is agnostic to downstream
fine-tuning or even re-training from scratch; (iii) it naturally evades
defenses that rely on inspecting model parameters or training data. With
extensive evaluation on benchmark datasets, we show that EVAS features high
evasiveness, transferability, and robustness, thereby expanding the adversary's
design spectrum. We further characterize the mechanisms underlying EVAS, which
are possibly explainable by architecture-level ``shortcuts'' that recognize
trigger patterns. This work raises concerns about the current practice of NAS
and points to potential directions to develop effective countermeasures
Audio is all in one: speech-driven gesture synthetics using WavLM pre-trained model
The generation of co-speech gestures for digital humans is an emerging area
in the field of virtual human creation. Prior research has made progress by
using acoustic and semantic information as input and adopting classify method
to identify the person's ID and emotion for driving co-speech gesture
generation. However, this endeavour still faces significant challenges. These
challenges go beyond the intricate interplay between co-speech gestures, speech
acoustic, and semantics; they also encompass the complexities associated with
personality, emotion, and other obscure but important factors. This paper
introduces "diffmotion-v2," a speech-conditional diffusion-based and
non-autoregressive transformer-based generative model with WavLM pre-trained
model. It can produce individual and stylized full-body co-speech gestures only
using raw speech audio, eliminating the need for complex multimodal processing
and manually annotated. Firstly, considering that speech audio not only
contains acoustic and semantic features but also conveys personality traits,
emotions, and more subtle information related to accompanying gestures, we
pioneer the adaptation of WavLM, a large-scale pre-trained model, to extract
low-level and high-level audio information. Secondly, we introduce an adaptive
layer norm architecture in the transformer-based layer to learn the
relationship between speech information and accompanying gestures. Extensive
subjective evaluation experiments are conducted on the Trinity, ZEGGS, and BEAT
datasets to confirm the WavLM and the model's ability to synthesize natural
co-speech gestures with various styles.Comment: 10 pages, 5 figures, 1 tabl
Defending Pre-trained Language Models as Few-shot Learners against Backdoor Attacks
Pre-trained language models (PLMs) have demonstrated remarkable performance
as few-shot learners. However, their security risks under such settings are
largely unexplored. In this work, we conduct a pilot study showing that PLMs as
few-shot learners are highly vulnerable to backdoor attacks while existing
defenses are inadequate due to the unique challenges of few-shot scenarios. To
address such challenges, we advocate MDP, a novel lightweight, pluggable, and
effective defense for PLMs as few-shot learners. Specifically, MDP leverages
the gap between the masking-sensitivity of poisoned and clean samples: with
reference to the limited few-shot data as distributional anchors, it compares
the representations of given samples under varying masking and identifies
poisoned samples as ones with significant variations. We show analytically that
MDP creates an interesting dilemma for the attacker to choose between attack
effectiveness and detection evasiveness. The empirical evaluation using
benchmark datasets and representative attacks validates the efficacy of MDP.Comment: Accepted by NeurIPS'2
An Embarrassingly Simple Backdoor Attack on Self-supervised Learning
As a new paradigm in machine learning, self-supervised learning (SSL) is
capable of learning high-quality representations of complex data without
relying on labels. In addition to eliminating the need for labeled data,
research has found that SSL improves the adversarial robustness over supervised
learning since lacking labels makes it more challenging for adversaries to
manipulate model predictions. However, the extent to which this robustness
superiority generalizes to other types of attacks remains an open question.
We explore this question in the context of backdoor attacks. Specifically, we
design and evaluate CTRL, an embarrassingly simple yet highly effective
self-supervised backdoor attack. By only polluting a tiny fraction of training
data (<= 1%) with indistinguishable poisoning samples, CTRL causes any
trigger-embedded input to be misclassified to the adversary's designated class
with a high probability (>= 99%) at inference time. Our findings suggest that
SSL and supervised learning are comparably vulnerable to backdoor attacks. More
importantly, through the lens of CTRL, we study the inherent vulnerability of
SSL to backdoor attacks. With both empirical and analytical evidence, we reveal
that the representation invariance property of SSL, which benefits adversarial
robustness, may also be the very reason making \ssl highly susceptible to
backdoor attacks. Our findings also imply that the existing defenses against
supervised backdoor attacks are not easily retrofitted to the unique
vulnerability of SSL.Comment: The 2023 International Conference on Computer Vision (ICCV '23
On the Security Risks of Knowledge Graph Reasoning
Knowledge graph reasoning (KGR) -- answering complex logical queries over
large knowledge graphs -- represents an important artificial intelligence task,
entailing a range of applications (e.g., cyber threat hunting). However,
despite its surging popularity, the potential security risks of KGR are largely
unexplored, which is concerning, given the increasing use of such capability in
security-critical domains.
This work represents a solid initial step towards bridging the striking gap.
We systematize the security threats to KGR according to the adversary's
objectives, knowledge, and attack vectors. Further, we present ROAR, a new
class of attacks that instantiate a variety of such threats. Through empirical
evaluation in representative use cases (e.g., medical decision support, cyber
threat hunting, and commonsense reasoning), we demonstrate that ROAR is highly
effective to mislead KGR to suggest pre-defined answers for target queries, yet
with negligible impact on non-target ones. Finally, we explore potential
countermeasures against ROAR, including filtering of potentially poisoning
knowledge and training with adversarially augmented queries, which leads to
several promising research directions.Comment: In proceedings of USENIX Security'23. Codes:
https://github.com/HarrialX/security-risk-KG-reasonin
Low expression of Notch1 may be associated with acute myocardial infarction
BackgroundThe transmembrane protein Notch1 is associated with cell growth, development, differentiation, proliferation, apoptosis, adhesion, and the epithelial mesenchymal transition. Proteomics, as a research method, uses a series of sequencing techniques to study the composition, expression levels, and modifications of proteins. Here, the association between Notch1 and acute myocardial infarction (AMI) was investigated using proteomics, to assess the possibility of using Notch1 as a biomarker for the disease.MethodsFifty-five eligible patients with AMI and 74 with chronic coronary syndrome (CCS) were enrolled, representing the experimental and control groups, respectively. The mRNA levels were assessed using RT-qPCR and proteins were measured using ELISA, and the results were compared and analyzed.ResultsNotch1 mRNA levels were 0.52 times higher in the peripheral blood mononuclear cells of the AMI group relative to the CCS group (p < 0.05) while Notch1 protein levels were 0.63 times higher in peripheral blood plasma in AMI patients (p < 0.05). Notch1 levels were not associated with older age, hypertension, smoking, high abdominal-blood glucose, high total cholesterol, and high LDL in AMI. Logistic regression indicated associations between AMI and reduced Notch1 expression, hypertension, smoking, and high fasting glucose.ConclusionsNotch1 expression was reduced in the peripheral blood of patients with AMI relative to those with CCS. The low expression of Notch1 was found to be an independent risk factor for AMI and may thus be an indicator of the disease
Potential of Core-Collapse Supernova Neutrino Detection at JUNO
JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve
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