42 research outputs found
AniPortraitGAN: Animatable 3D Portrait Generation from 2D Image Collections
Previous animatable 3D-aware GANs for human generation have primarily focused
on either the human head or full body. However, head-only videos are relatively
uncommon in real life, and full body generation typically does not deal with
facial expression control and still has challenges in generating high-quality
results. Towards applicable video avatars, we present an animatable 3D-aware
GAN that generates portrait images with controllable facial expression, head
pose, and shoulder movements. It is a generative model trained on unstructured
2D image collections without using 3D or video data. For the new task, we base
our method on the generative radiance manifold representation and equip it with
learnable facial and head-shoulder deformations. A dual-camera rendering and
adversarial learning scheme is proposed to improve the quality of the generated
faces, which is critical for portrait images. A pose deformation processing
network is developed to generate plausible deformations for challenging regions
such as long hair. Experiments show that our method, trained on unstructured 2D
images, can generate diverse and high-quality 3D portraits with desired control
over different properties.Comment: SIGGRAPH Asia 2023. Project Page:
https://yuewuhkust.github.io/AniPortraitGAN
Dirac operators and monopoles with singularities
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mathematics, 2007.Includes bibliographical references (p. 75-77).This thesis consists of two parts. In the first part of the thesis, we prove an index theorem for Dirac operators of conic singularities with codimension 2. One immediate corollary is the generalized Rohklin congruence formula. The eta function for a twisted spin Dirac operator on a circle bundle over a even dimensional spin manifold is also derived along the way. In the second part, we study the moduli space of monopoles with singularities along an embedded surface. We prove that when the base manifold is Kahler, there is a holomorphic description of the singular monopoles. The compactness for this case is also proved.by Fangyun Yang.Ph.D
U-shaped relationship between managerial herd behavior and corporate financialization with the moderating effect of corporate governance: evidence from China
Based on behavioral finance theory, we discuss the influence of managers’ herd behavior on corporate financialization from the perspective of managers’ behavioral preferences. Empirical testing was conducted using data from nonfinancial listed firms on the Shanghai and Shenzhen A-shares from 2007 to 2021 and a U-shaped relationship was found between managerial herd behavior and corporate financialization. When managerial herd behavior is within an appropriate range, the increase in managerial herd behavior has a negative influence on corporate financialization. In contrast, excessive managerial herd behavior leads to excessive corporate financialization. Additionally, corporate governance has a weakening effect on this relationship. Heterogeneity analyses indicate significant disparities in the effect of managerial herd behavior on corporate financialization among enterprises with diverse ownership structures. Finally, corporate financialization and innovation investments have an inverted U-shaped relationship, and their relationship is moderated positively by management herd behavior. Our results have strong practical significance for fostering the balanced growth of the financial sector and the real economy.
First published online 05 January 202
Attentive Mask CLIP
Image token removal is an efficient augmentation strategy for reducing the
cost of computing image features. However, this efficient augmentation strategy
has been found to adversely affect the accuracy of CLIP-based training. We
hypothesize that removing a large portion of image tokens may improperly
discard the semantic content associated with a given text description, thus
constituting an incorrect pairing target in CLIP training. To address this
issue, we propose an attentive token removal approach for CLIP training, which
retains tokens with a high semantic correlation to the text description. The
correlation scores are computed in an online fashion using the EMA version of
the visual encoder. Our experiments show that the proposed attentive masking
approach performs better than the previous method of random token removal for
CLIP training. The approach also makes it efficient to apply multiple
augmentation views to the image, as well as introducing instance contrastive
learning tasks between these views into the CLIP framework. Compared to other
CLIP improvements that combine different pre-training targets such as SLIP and
MaskCLIP, our method is not only more effective, but also much more efficient.
Specifically, using ViT-B and YFCC-15M dataset, our approach achieves
top-1 accuracy on ImageNet-1K zero-shot classification, as well as
and I2T/T2I retrieval accuracy on Flickr30K and MS COCO, which are
, , and higher than the SLIP method, while being
faster. An efficient version of our approach running
faster than the plain CLIP model achieves significant gains of ,
, and on these benchmarks
When Does Trust Reinforce Intentions to Upgrade to Paid Online Healthcare Consultations? The Valence of Platform-Versus Service-Related Attitudes
For online healthcare businesses with a multi-tier pricing model, how to motivate patients to pay for high-end services is an important issue. Drawing on the freemium literature and the valence framework, we examined seven service quality-related antecedents of patients’ intentions to upgrade to premium services in the context of online healthcare consultation (OHC). We hypothesized that patients’ perceptions of OHC platform quality, free OHC service quality, and free OHC adoption risks should exert counterbalanced, direct impacts on their intentions to upgrade to premium services. Furthermore, the net outcome of this dual effect may be contingent on patients’ trust in the platform. We conducted an empirical study by surveying 409 OHC consumers in China. Preliminary results support the direct effects of platform- and service-related evaluations for both their benefits and risks. The moderating analysis supports the effect of trust on mitigating the negative impacts of risk perceptions on upgrading intentions
Correction: Transarterial strategies for the treatment of unresectable hepatocellular carcinoma: A systematic review.
[This corrects the article DOI: 10.1371/journal.pone.0227475.]
Transarterial strategies for the treatment of unresectable hepatocellular carcinoma: A systematic review.
Conventional transarterial chemoembolization (cTACE), drug-eluting beads (DEB-TACE) and transarterial radioembolization (TARE) are alternative strategies for unresectable hepatocellular carcinoma (HCC). However, which of these strategies is the best is still controversial. This meta-analysis was performed to evaluate the effects of DEB-TACE, TARE and cTACE in terms of overall survival (OS), tumor response and complications. A literature search was conducted using the EMBASE, PubMed, Google Scholar, and Cochrane databases from inception until July 2019 with no language restrictions. The primary outcome was overall survival, and the secondary outcomes included complete response and local recurrence. The comparison of DEB-TACE with cTACE indicated that DEB-TACE has a better OS at 1 year (RR 0.79, 95% CI 0.67-0.93, p = 0.006), 2 years (RR 0.89; 95% CI 0.81-0.99, p = 0.046), and 3 years (RR 0.89; 95% CI 0.81-0.99, p = 0.035). The comparison of TARE with cTACE indicated that TARE has a better OS than cTACE at 2 years (RR 0.87; 95% CI 0.80-0.95, p = 0.003) and 3 years (RR 0.90; 95% CI 0.85-0.96, p = 0.001). The comparison of DEB-TACE with TARE indicated that DEB-TACE has a better OS than TARE at 2 years (RR 0.40; 95% CI 0.19-0.84, p = 0.016). The current meta-analysis suggests that DEB-TACE is superior to both TARE and cTACE in terms of OS. TARE has significantly lower complications than both DEB-TACE and cTACE for patients with HCC. Further multicenter, well-designed randomized controlled trials are needed, especially for evaluating DEB-TACE versus TARE