1,733 research outputs found
Systematic Digitized Treatment of Engineering Line-Diagrams
YesIn engineering design, there are many functional relationships which are difficult to express into a simple and exact mathematical formula. Instead they are documented within a form of line graphs (or plot charts or curve diagrams) in engineering handbooks or text books. Because the information in such a form cannot be used directly in the modern computer aided design (CAD) process, it is necessary to find a way to numerically represent the information. In this paper, a data processing system for numerical representation of line graphs in mechanical design is developed, which incorporates the process cycle from the initial data acquisition to the final output of required information. As well as containing the capability for curve fitting through Cubic spline and Neural network techniques, the system also adapts a novel methodology for use in this application: Grey Models. Grey theory have been used in various applications, normally involved with time-series data, and have the characteristic of being able to handle sparse data sets and data forecasting. Two case studies were then utilized to investigate the feasibility of Grey models for curve fitting. Furthermore, comparisons with the other two established techniques show that the accuracy was better than the Cubic spline function method, but slightly less accurate than the Neural network method. These results are highly encouraging and future work to fully investigate the capability of Grey theory, as well as exploiting its sparse data handling capabilities is recommended
Effect of Attention and Self-Supervised Speech Embeddings on Non-Semantic Speech Tasks
Human emotion understanding is pivotal in making conversational technology
mainstream. We view speech emotion understanding as a perception task which is
a more realistic setting. With varying contexts (languages, demographics, etc.)
different share of people perceive the same speech segment as a non-unanimous
emotion. As part of the ACM Multimedia 2023 Computational Paralinguistics
ChallengE (ComParE) in the EMotion Share track, we leverage their rich dataset
of multilingual speakers and multi-label regression target of 'emotion share'
or perception of that emotion. We demonstrate that the training scheme of
different foundation models dictates their effectiveness for tasks beyond
speech recognition, especially for non-semantic speech tasks like emotion
understanding. This is a very complex task due to multilingual speakers,
variability in the target labels, and inherent imbalance in the regression
dataset. Our results show that HuBERT-Large with a self-attention-based
light-weight sequence model provides 4.6% improvement over the reported
baseline.Comment: Accepted to appear at ACM Multimedia 2023 Multimedia Grand Challenges
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The shadows of accelerating Kerr-Newman black hole and constraints from M87*
In this paper, we study the influence of the parameters for the accelerating
Kerr-Newman black hole on the shadows and the constraints, extensively. We find
that the rotating parameter , the charge parameter , and the inclination
angle affect the shadow qualitatively similar to that of Kerr-Newman
black holes. The result shows that the size of the shadow will scale down with
the accelerating factor . Besides, the factor also can affect the best
viewing angles, which make the observations maximum deviate from
, and the degree of the deviations are less than .
Then, we assume the M87* as an accelerating Kerr-Newman black hole with the
mass and the distance . Combining the EHT
observations, we find that neither the observations, circularity deviation
or axial ratio can distinguish the accelerating black hole or
not. However, the characteristic areal-radius of the shadow curve can
give corresponding constraints on the parameters of the accelerating
Kerr-Newman black hole. The results shows that the bigger accelerating factor
is, the stronger constraints on the rotating parameter and charged
parameter . {The maximum range of the accelerating factor is
for a accelerating Schwarzschild case with , and for an extremely
slow accelerating case , the ranges of rotating parameter
and charged parameter are and .Comment: 9 pages, 16figure
Jacobian Methods for Dynamic Polarization Control in Optical Applications
Dynamic polarization control (DPC) is beneficial for many optical
applications. It uses adjustable waveplates to perform automatic polarization
tracking and manipulation. Efficient algorithms are essential to realizing an
endless polarization control process at high speed. However, the standard
gradientbased algorithm is not well analyzed. Here we model the DPC with a
Jacobian-based control theory framework that finds a lot in common with robot
kinematics. We then give a detailed analysis of the condition of the Stokes
vector gradient as a Jacobian matrix. We identify the multi-stage DPC as a
redundant system enabling control algorithms with null-space operations. An
efficient, reset-free algorithm can be found. We anticipate more customized DPC
algorithms to follow the same framework in various optical systems
Reconstruction of relativistic modified Newtonian dynamics for various cosmological scenarios
In this paper, we present several explicit reconstructions for a novel
relativistic theory of modified Newtonian dynamics (RMOND) derived from the
background of Friedmann-Lematre-Robertson-Walker cosmological
evolution. It is shown that the Einstein-Hilbert Lagrangian with a positive
cosmological constant is the only Lagrangian capable of accurately replicating
the exact expansion history of the cold dark matter (CDM)
universe filled solely with dust-like matter and the only way to achieve this
expansion history for the RMOND theory is to introduce additional degrees of
freedom to the matter sectors. Besides, we find that the CDM-era also
can be replicated without any real matter field within the framework of the
RMOND theory and the cosmic evolution exhibited by both the power-law and
de-Sitter solutions also can be obtained
Neural encoding of socially adjusted value during competitive and hazardous foraging
In group foraging organisms, optimizing the conflicting demands of competitive food loss and safety is critical. We demonstrate that humans select competition avoidant and risk diluting strategies during foraging depending on socially adjusted value. We formulate a mathematically grounded quantification of socially adjusted value in foraging environments and show using multivariate fMRI analyses that socially adjusted value is encoded by mid-cingulate and ventromedial prefrontal cortices, regions that integrate value and action signals
The Role of the Medial Prefrontal Cortex in Spatial Margin of Safety Calculations
Humans, like many other animals, pre-empt danger by moving to locations that maximize their success at escaping future threats. We test the idea that spatial margin of safety (MOS) decisions, a form of pre-emptive avoidance, results in participants placing themselves closer to safer locations when facing more unpredictable threats. Using multivariate pattern analysis on fMRI data collected while subjects engaged in MOS decisions with varying attack location predictability, we show that while the hippocampus encodes MOS decisions across all types of threat, a vmPFC anterior-posterior gradient tracked threat predictability. The posterior vmPFC encoded for more unpredictable threat and showed functional coupling with the amygdala and hippocampus. Conversely, the anterior vmPFC was more active for the more predictable attacks and showed coupling with the striatum. Our findings suggest that when pre-empting danger, the anterior vmPFC may provide a safety signal, possibly via predictable positive outcomes, while the posterior vmPFC drives prospective danger signals
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Preliminary prediction of individual response to electroconvulsive therapy using whole-brain functional magnetic resonance imaging data.
Electroconvulsive therapy (ECT) works rapidly and has been widely used to treat depressive disorders (DEP). However, identifying biomarkers predictive of response to ECT remains a priority to individually tailor treatment and understand treatment mechanisms. This study used a connectome-based predictive modeling (CPM) approach in 122 patients with DEP to determine if pre-ECT whole-brain functional connectivity (FC) predicts depressive rating changes and remission status after ECT (47 of 122 total subjects or 38.5% of sample), and whether pre-ECT and longitudinal changes (pre/post-ECT) in regional brain network biomarkers are associated with treatment-related changes in depression ratings. Results show the networks with the best predictive performance of ECT response were negative (anti-correlated) FC networks, which predict the post-ECT depression severity (continuous measure) with a 76.23% accuracy for remission prediction. FC networks with the greatest predictive power were concentrated in the prefrontal and temporal cortices and subcortical nuclei, and include the inferior frontal (IFG), superior frontal (SFG), superior temporal (STG), inferior temporal gyri (ITG), basal ganglia (BG), and thalamus (Tha). Several of these brain regions were also identified as nodes in the FC networks that show significant change pre-/post-ECT, but these networks were not related to treatment response. This study design has limitations regarding the longitudinal design and the absence of a control group that limit the causal inference regarding mechanism of post-treatment status. Though predictive biomarkers remained below the threshold of those recommended for potential translation, the analysis methods and results demonstrate the promise and generalizability of biomarkers for advancing personalized treatment strategies
StereoPose: Category-Level 6D Transparent Object Pose Estimation from Stereo Images via Back-View NOCS
Most existing methods for category-level pose estimation rely on object point
clouds. However, when considering transparent objects, depth cameras are
usually not able to capture meaningful data, resulting in point clouds with
severe artifacts. Without a high-quality point cloud, existing methods are not
applicable to challenging transparent objects. To tackle this problem, we
present StereoPose, a novel stereo image framework for category-level object
pose estimation, ideally suited for transparent objects. For a robust
estimation from pure stereo images, we develop a pipeline that decouples
category-level pose estimation into object size estimation, initial pose
estimation, and pose refinement. StereoPose then estimates object pose based on
representation in the normalized object coordinate space~(NOCS). To address the
issue of image content aliasing, we further define a back-view NOCS map for the
transparent object. The back-view NOCS aims to reduce the network learning
ambiguity caused by content aliasing, and leverage informative cues on the back
of the transparent object for more accurate pose estimation. To further improve
the performance of the stereo framework, StereoPose is equipped with a parallax
attention module for stereo feature fusion and an epipolar loss for improving
the stereo-view consistency of network predictions. Extensive experiments on
the public TOD dataset demonstrate the superiority of the proposed StereoPose
framework for category-level 6D transparent object pose estimation.Comment: 7 pages, 6 figures, Project homepage:
https://appsrv.cse.cuhk.edu.hk/~kaichen/stereopose.htm
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