14 research outputs found
Performance Evaluation of Channel Decoding With Deep Neural Networks
With the demand of high data rate and low latency in fifth generation (5G),
deep neural network decoder (NND) has become a promising candidate due to its
capability of one-shot decoding and parallel computing. In this paper, three
types of NND, i.e., multi-layer perceptron (MLP), convolution neural network
(CNN) and recurrent neural network (RNN), are proposed with the same parameter
magnitude. The performance of these deep neural networks are evaluated through
extensive simulation. Numerical results show that RNN has the best decoding
performance, yet at the price of the highest computational overhead. Moreover,
we find there exists a saturation length for each type of neural network, which
is caused by their restricted learning abilities.Comment: 6 pages, 11 figures, Latex; typos corrected; IEEE ICC 2018 to appea
MATLABER: Material-Aware Text-to-3D via LAtent BRDF auto-EncodeR
Based on powerful text-to-image diffusion models, text-to-3D generation has
made significant progress in generating compelling geometry and appearance.
However, existing methods still struggle to recover high-fidelity object
materials, either only considering Lambertian reflectance, or failing to
disentangle BRDF materials from the environment lights. In this work, we
propose Material-Aware Text-to-3D via LAtent BRDF auto-EncodeR
(\textbf{MATLABER}) that leverages a novel latent BRDF auto-encoder for
material generation. We train this auto-encoder with large-scale real-world
BRDF collections and ensure the smoothness of its latent space, which
implicitly acts as a natural distribution of materials. During appearance
modeling in text-to-3D generation, the latent BRDF embeddings, rather than BRDF
parameters, are predicted via a material network. Through exhaustive
experiments, our approach demonstrates the superiority over existing ones in
generating realistic and coherent object materials. Moreover, high-quality
materials naturally enable multiple downstream tasks such as relighting and
material editing. Code and model will be publicly available at
\url{https://sheldontsui.github.io/projects/Matlaber}
Fastened CROWN: Tightened Neural Network Robustness Certificates
The rapid growth of deep learning applications in real life is accompanied by
severe safety concerns. To mitigate this uneasy phenomenon, much research has
been done providing reliable evaluations of the fragility level in different
deep neural networks. Apart from devising adversarial attacks, quantifiers that
certify safeguarded regions have also been designed in the past five years. The
summarizing work of Salman et al. unifies a family of existing verifiers under
a convex relaxation framework. We draw inspiration from such work and further
demonstrate the optimality of deterministic CROWN (Zhang et al. 2018) solutions
in a given linear programming problem under mild constraints. Given this
theoretical result, the computationally expensive linear programming based
method is shown to be unnecessary. We then propose an optimization-based
approach \textit{FROWN} (\textbf{F}astened C\textbf{ROWN}): a general algorithm
to tighten robustness certificates for neural networks. Extensive experiments
on various networks trained individually verify the effectiveness of FROWN in
safeguarding larger robust regions.Comment: Zhaoyang Lyu and Ching-Yun Ko contributed equally, accepted to AAAI
202
The Annual Rhythmic Differentiation of Populus davidiana Growth–Climate Response Under a Warming Climate in The Greater Hinggan Mountains
The stability and balance of forest ecosystems have been seriously affected by climate change. Herein, we use dendrochronological methods to investigate the radial growth and climate response of pioneer tree species in the southern margin of cold temperate coniferous forest based on Populus davidiana growing on the Greater Hinggan Mountains in northeastern China. Correlations of P. davidiana growth with temperature and precipitation in a year (October–September) were rhythmically opposed: while temperatures in previous October–June (winter and spring) and in May–September (growing season) respectively inhibited and promoted radial growth on P. davidiana (p \u3c 0.01), precipitation in the same periods respectively promoted and inhibited of growth (p \u3c 0.01). High temperature or less rain/snow in winter and early spring, and low temperature or excess rainfall in summer, are inconducive to P. davidiana growth and vice versa (p \u3c 0.01). In addition, in March–April, when air temperature was above 0 °C and ground temperature below 0 °C, physiological drought caused significant growth inhibition in P. davidiana (p \u3c 0.05). In general, temperatures play a driving and controlling role in the synergistic effect of temperature and precipitation on P. davidiana growth. Under current conditions of available water supply, changes of temperature, especially warming, are beneficial to the growth of P. davidiana in the study area. The current climate conditions promote the growth of P. davidiana, the pioneer species, compared with the growth inhibition of Larix gmelinii, the dominant species. Thus, the structure and function of boreal forest might be changed under global warming by irreversible alterations in the growth and composition of coniferous and broadleaf tree species in the forest
DiffBIR: Towards Blind Image Restoration with Generative Diffusion Prior
We present DiffBIR, which leverages pretrained text-to-image diffusion models
for blind image restoration problem. Our framework adopts a two-stage pipeline.
In the first stage, we pretrain a restoration module across diversified
degradations to improve generalization capability in real-world scenarios. The
second stage leverages the generative ability of latent diffusion models, to
achieve realistic image restoration. Specifically, we introduce an injective
modulation sub-network -- LAControlNet for finetuning, while the pre-trained
Stable Diffusion is to maintain its generative ability. Finally, we introduce a
controllable module that allows users to balance quality and fidelity by
introducing the latent image guidance in the denoising process during
inference. Extensive experiments have demonstrated its superiority over
state-of-the-art approaches for both blind image super-resolution and blind
face restoration tasks on synthetic and real-world datasets. The code is
available at https://github.com/XPixelGroup/DiffBIR
Accelerating Diffusion Models via Early Stop of the Diffusion Process
Denoising Diffusion Probabilistic Models (DDPMs) have achieved impressive
performance on various generation tasks. By modeling the reverse process of
gradually diffusing the data distribution into a Gaussian distribution,
generating a sample in DDPMs can be regarded as iteratively denoising a
randomly sampled Gaussian noise. However, in practice DDPMs often need hundreds
even thousands of denoising steps to obtain a high-quality sample from the
Gaussian noise, leading to extremely low inference efficiency. In this work, we
propose a principled acceleration strategy, referred to as Early-Stopped DDPM
(ES-DDPM), for DDPMs. The key idea is to stop the diffusion process early where
only the few initial diffusing steps are considered and the reverse denoising
process starts from a non-Gaussian distribution. By further adopting a powerful
pre-trained generative model, such as GAN and VAE, in ES-DDPM, sampling from
the target non-Gaussian distribution can be efficiently achieved by diffusing
samples obtained from the pre-trained generative model. In this way, the number
of required denoising steps is significantly reduced. In the meantime, the
sample quality of ES-DDPM also improves substantially, outperforming both the
vanilla DDPM and the adopted pre-trained generative model. On extensive
experiments across CIFAR-10, CelebA, ImageNet, LSUN-Bedroom and LSUN-Cat,
ES-DDPM obtains promising acceleration effect and performance improvement over
representative baseline methods. Moreover, ES-DDPM also demonstrates several
attractive properties, including being orthogonal to existing acceleration
methods, as well as simultaneously enabling both global semantic and local
pixel-level control in image generation.Comment: Code is released at https://github.com/ZhaoyangLyu/Early_Stopped_DDP
Fastened CROWN: Tightened Neural Network Robustness Certificates
The rapid growth of deep learning applications in real life is accompanied by severe safety concerns. To mitigate this uneasy phenomenon, much research has been done providing reliable evaluations of the fragility level in different deep neural networks. Apart from devising adversarial attacks, quantifiers that certify safeguarded regions have also been designed in the past five years. The summarizing work in (Salman et al. 2019) unifies a family of existing verifiers under a convex relaxation framework. We draw inspiration from such work and further demonstrate the optimality of deterministic CROWN (Zhang et al. 2018) solutions in a given linear programming problem under mild constraints. Given this theoretical result, the computationally expensive linear programming based method is shown to be unnecessary. We then propose an optimization-based approach FROWN (Fastened CROWN): a general algorithm to tighten robustness certificates for neural networks. Extensive experiments on various networks trained individually verify the effectiveness of FROWN in safeguarding larger robust regions.</jats:p
Fastened CROWN: Tightened Neural Network Robustness Certificates
The rapid growth of deep learning applications in real life is accompanied by severe safety concerns. To mitigate this uneasy phenomenon, much research has been done providing reliable evaluations of the fragility level in different deep neural networks. Apart from devising adversarial attacks, quantifiers that certify safeguarded regions have also been designed in the past five years. The summarizing work in (Salman et al. 2019) unifies a family of existing verifiers under a convex relaxation framework. We draw inspiration from such work and further demonstrate the optimality of deterministic CROWN (Zhang et al. 2018) solutions in a given linear programming problem under mild constraints. Given this theoretical result, the computationally expensive linear programming based method is shown to be unnecessary. We then propose an optimization-based approach FROWN (Fastened CROWN): a general algorithm to tighten robustness certificates for neural networks. Extensive experiments on various networks trained individually verify the effectiveness of FROWN in safeguarding larger robust regions
A GIS-Based Method for Identification of Blindness in Former Site Selection of Sewage Treatment Plants and Exploration of Optimal Siting Areas: A Case Study in Liao River Basin
With regard to environmental facilities, blindness and the subjectivity of site selection lead to serious economic, engineering and social problems. A proper siting proposal often poses a challenge to local governments, as multiple factors should be considered, such as costs, construction conditions and social impact. How to make the optimal siting decision has become a topical issue in academic circles. In order to enrich the framework of site selection models, this study combined GIS, AHP and Remote Sensing (RS) technologies to conduct siting suitability analysis of sewage treatment plants, and it was first applied in the Liao River basin in Jilin Province in China. The enriched model is able to reveal blindness in the former site selection of sewage treatment plants and explore optimal siting areas, involving an effective quantification method for summer dominant wind direction and urban stream direction. In a case study, it was found that local governments need to be cautious of the distance of sites from rivers and residential areas and the impact of these sites on downwind and downstream residents. Additionally, siting suitability has obvious regional characteristics, and its distribution varies significantly between towns. Huaide Town shows the largest optimal siting areas and can be given priority for the construction of new sewage treatment plants. This paper developed a more scientific approach to site selection, and the outcome can provide a robust reference for local governments