15 research outputs found
DeepSketchHair: Deep Sketch-based 3D Hair Modeling
We present sketchhair, a deep learning based tool for interactive modeling of
3D hair from 2D sketches. Given a 3D bust model as reference, our sketching
system takes as input a user-drawn sketch (consisting of hair contour and a few
strokes indicating the hair growing direction within a hair region), and
automatically generates a 3D hair model, which matches the input sketch both
globally and locally. The key enablers of our system are two carefully designed
neural networks, namely, S2ONet, which converts an input sketch to a dense 2D
hair orientation field; and O2VNet, which maps the 2D orientation field to a 3D
vector field. Our system also supports hair editing with additional sketches in
new views. This is enabled by another deep neural network, V2VNet, which
updates the 3D vector field with respect to the new sketches. All the three
networks are trained with synthetic data generated from a 3D hairstyle
database. We demonstrate the effectiveness and expressiveness of our tool using
a variety of hairstyles and also compare our method with prior art
DCL: Differential Contrastive Learning for Geometry-Aware Depth Synthesis
We describe a method for unpaired realistic depth synthesis that learns
diverse variations from the real-world depth scans and ensures geometric
consistency between the synthetic and synthesized depth. The synthesized
realistic depth can then be used to train task-specific networks facilitating
label transfer from the synthetic domain. Unlike existing image synthesis
pipelines, where geometries are mostly ignored, we treat geometries carried by
the depth scans based on their own existence. We propose differential
contrastive learning that explicitly enforces the underlying geometric
properties to be invariant regarding the real variations been learned. The
resulting depth synthesis method is task-agnostic, and we demonstrate the
effectiveness of the proposed synthesis method by extensive evaluations on
real-world geometric reasoning tasks. The networks trained with the depth
synthesized by our method consistently achieve better performance across a wide
range of tasks than state of the art, and can even surpass the networks
supervised with full real-world annotations when slightly fine-tuned, showing
good transferability.Comment: Accepted by International Conference on Robotics and Automation
(ICRA) 2022 and RA-L 202
MonoHair: High-Fidelity Hair Modeling from a Monocular Video
Undoubtedly, high-fidelity 3D hair is crucial for achieving realism, artistic
expression, and immersion in computer graphics. While existing 3D hair modeling
methods have achieved impressive performance, the challenge of achieving
high-quality hair reconstruction persists: they either require strict capture
conditions, making practical applications difficult, or heavily rely on learned
prior data, obscuring fine-grained details in images. To address these
challenges, we propose MonoHair,a generic framework to achieve high-fidelity
hair reconstruction from a monocular video, without specific requirements for
environments. Our approach bifurcates the hair modeling process into two main
stages: precise exterior reconstruction and interior structure inference. The
exterior is meticulously crafted using our Patch-based Multi-View Optimization
(PMVO). This method strategically collects and integrates hair information from
multiple views, independent of prior data, to produce a high-fidelity exterior
3D line map. This map not only captures intricate details but also facilitates
the inference of the hair's inner structure. For the interior, we employ a
data-driven, multi-view 3D hair reconstruction method. This method utilizes 2D
structural renderings derived from the reconstructed exterior, mirroring the
synthetic 2D inputs used during training. This alignment effectively bridges
the domain gap between our training data and real-world data, thereby enhancing
the accuracy and reliability of our interior structure inference. Lastly, we
generate a strand model and resolve the directional ambiguity by our hair
growth algorithm. Our experiments demonstrate that our method exhibits
robustness across diverse hairstyles and achieves state-of-the-art performance.
For more results, please refer to our project page
https://keyuwu-cs.github.io/MonoHair/.Comment: Accepted by IEEE CVPR 202
GCN-Denoiser: Mesh Denoising with Graph Convolutional Networks
In this paper, we present GCN-Denoiser, a novel feature-preserving mesh
denoising method based on graph convolutional networks (GCNs). Unlike previous
learning-based mesh denoising methods that exploit hand-crafted or voxel-based
representations for feature learning, our method explores the structure of a
triangular mesh itself and introduces a graph representation followed by graph
convolution operations in the dual space of triangles. We show such a graph
representation naturally captures the geometry features while being lightweight
for both training and inference. To facilitate effective feature learning, our
network exploits both static and dynamic edge convolutions, which allow us to
learn information from both the explicit mesh structure and potential implicit
relations among unconnected neighbors. To better approximate an unknown noise
function, we introduce a cascaded optimization paradigm to progressively
regress the noise-free facet normals with multiple GCNs. GCN-Denoiser achieves
the new state-of-the-art results in multiple noise datasets, including CAD
models often containing sharp features and raw scan models with real noise
captured from different devices. We also create a new dataset called PrintData
containing 20 real scans with their corresponding ground-truth meshes for the
research community. Our code and data are available in
https://github.com/Jhonve/GCN-Denoiser.Comment: Accepted by ACM Transactions on Graphics 202
Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo
Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level
Ultralight vector dark matter search using data from the KAGRA O3GK run
Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM
Wind Turbine Blade Defect Detection Based on Acoustic Features and Small Sample Size
Wind power has become an important source of electricity for both production and domestic use. However, because wind turbines often operate in harsh environments, they are prone to cracks, blisters, and corrosion of the blade surface. If these defects cannot be repaired in time, the cracks evolve into larger fractures, which can lead to blade rupture. As such, in this study, we developed a remote non-contact online health monitoring and warning system for wind turbine blades based on acoustic features and artificial neural networks. Collecting a large number of wind turbine blade defect signals was challenging. To address this issue, we designed an acoustic detection method based on a small sample size. We employed the octave to extract defect information, and we used an artificial neural network based on model-agnostic meta-learning (MAML-ANN) for classification. We analyzed the influence of locations and compared the performance of MAML-ANN with that of traditional ANN. The experimental results showed that the accuracy of our method reached 94.1% when each class contained only 50 data; traditional ANN achieved an accuracy of only 85%. With MAML-ANN, the training is fast and the global optimal solution is automatic searched, and it can be expanded to situations with a large sample size
Wind Turbine Blade Defect Detection Based on Acoustic Features and Small Sample Size
Wind power has become an important source of electricity for both production and domestic use. However, because wind turbines often operate in harsh environments, they are prone to cracks, blisters, and corrosion of the blade surface. If these defects cannot be repaired in time, the cracks evolve into larger fractures, which can lead to blade rupture. As such, in this study, we developed a remote non-contact online health monitoring and warning system for wind turbine blades based on acoustic features and artificial neural networks. Collecting a large number of wind turbine blade defect signals was challenging. To address this issue, we designed an acoustic detection method based on a small sample size. We employed the octave to extract defect information, and we used an artificial neural network based on model-agnostic meta-learning (MAML-ANN) for classification. We analyzed the influence of locations and compared the performance of MAML-ANN with that of traditional ANN. The experimental results showed that the accuracy of our method reached 94.1% when each class contained only 50 data; traditional ANN achieved an accuracy of only 85%. With MAML-ANN, the training is fast and the global optimal solution is automatic searched, and it can be expanded to situations with a large sample size
Domain Adaptation on Point Clouds via Geometry-Aware Implicits
As a popular geometric representation, point clouds have attracted much
attention in 3D vision, leading to many applications in autonomous driving and
robotics. One important yet unsolved issue for learning on point cloud is that
point clouds of the same object can have significant geometric variations if
generated using different procedures or captured using different sensors. These
inconsistencies induce domain gaps such that neural networks trained on one
domain may fail to generalize on others. A typical technique to reduce the
domain gap is to perform adversarial training so that point clouds in the
feature space can align. However, adversarial training is easy to fall into
degenerated local minima, resulting in negative adaptation gains. Here we
propose a simple yet effective method for unsupervised domain adaptation on
point clouds by employing a self-supervised task of learning geometry-aware
implicits, which plays two critical roles in one shot. First, the geometric
information in the point clouds is preserved through the implicit
representations for downstream tasks. More importantly, the domain-specific
variations can be effectively learned away in the implicit space. We also
propose an adaptive strategy to compute unsigned distance fields for arbitrary
point clouds due to the lack of shape models in practice. When combined with a
task loss, the proposed outperforms state-of-the-art unsupervised domain
adaptation methods that rely on adversarial domain alignment and more
complicated self-supervised tasks. Our method is evaluated on both PointDA-10
and GraspNet datasets. The code and trained models will be publicly available
The effects of crop rotation combinations on the soil quality of old apple orchard
This study investigated the effects of six crop rotation combinations on the soil quality of old apple orchard and seedling growth of Malus hupehensis Rehd. (apple rootstock) under pot conditions. The inhibitory effects of crops such as Allium fistulosum, Brassica juncea, and Triticum aestivum on four species of Fusarium were observed and compared in six treatments. These were continuous cropping (CK), fumigation with the methyl bromide (FM), rotating A. fistulosum only (R1), rotating A. fistulosum and T. aestivum (R2), rotating A. fistulosum, B. juncea, and T. aestivum (R3), and fallow (FC) in a year. The results showed that the biomass of Malus hupehensis Rehd. seedlings increased significantly. The root length increased and the root architecture was optimized. The respiration rate of the root system was increased by about 1 time after rotation. The treatments of R1, R2, R3, and FC increased bacterial count by 232.17%, 96.04%, 316.21%, and 60.02%, respectively. However, the fungi were reduced in varying degrees and bacteria/fungi ratio was increased by 5–10 times. The enzyme activities, pH, and organic matter were increased, but soil bulk density was decreased. Phenolic acids such as phloridzin was decreased significantly. The copy number of four Fusarium species declined by 85.59%, 74.94%, 69.68%, and 54.41% after rotating three different crops (R3 treatment). The root volatiles of three plants inhibited mycelial growth and spore germination of four Fusarium species