Deep Learning
Layer-Wise Adaptive Updating for Few-Shot Image Classification
Qin, Yunxiao, Zhang, Weiguo, Wang, Zezheng, Zhao, Chenxu, Shi, Jingping
Few-shot image classification (FSIC), which requires a model to recognize new categories via learning from few images of these categories, has attracted lots of attention. Recently, meta-learning based methods have been shown as a promising direction for FSIC. Commonly, they train a meta-learner (meta-learning model) to learn easy fine-tuning weight, and when solving an FSIC task, the meta-learner efficiently fine-tunes itself to a task-specific model by updating itself on few images of the task. In this paper, we propose a novel meta-learning based layer-wise adaptive updating (LWAU) method for FSIC. LWAU is inspired by an interesting finding that compared with common deep models, the meta-learner pays much more attention to update its top layer when learning from few images. According to this finding, we assume that the meta-learner may greatly prefer updating its top layer to updating its bottom layers for better FSIC performance. Therefore, in LWAU, the meta-learner is trained to learn not only the easy fine-tuning model but also its favorite layer-wise adaptive updating rule to improve its learning efficiency. Extensive experiments show that with the layer-wise adaptive updating rule, the proposed LWAU: 1) outperforms existing few-shot classification methods with a clear margin; 2) learns from few images more efficiently by at least 5 times than existing meta-learners when solving FSIC.
Detecting Out-of-distribution Samples via Variational Auto-encoder with Reliable Uncertainty Estimation
Ran, Xuming, Xu, Mingkun, Mei, Lingrui, Xu, Qi, Liu, Quanying
In unsupervised learning, variational auto-encoders (VAEs) are an influential class of deep generative models with rich representational power of neural networks and Bayesian methods. However, VAEs suffer from assigning higher likelihood to out-of-distribution (OOD) inputs than in-distribution (ID) inputs. Recent studies advise that the deep generative models with reliable uncertainty estimation is critical to a deep understanding of OOD inputs. Meanwhile, noise contrastive prior (NCP) is an emerging promising method for obtaining uncertainty, with the advantages of easy to scale, being trainable, and compatibility with extensive models. Inspired by these ideas, We propose an improved noise contrastive prior (INCP) to acquire reliable uncertainty estimate for standard VAEs. By combining INCP with the encoder of VAE, patterns between OOD and ID inputs can be well captured and distinguished. Our method outperforms standard VAEs on the FashionMNIST and CIFAR10 datasets. We also demonstrate the preferred robustness of our model by the extensive experiments on anomaly detection tasks.
Data-driven effective model shows a liquid-like deep learning
Geometric structure of an optimization landscape is argued to be fundamentally important to support the success of deep learning. However, recent research efforts focused on either of toy random models with unrealistic assumptions and numerical evidences about different shapes of the optimization landscape, thereby lacking a unified view about the nature of the landscape. Here, we propose a statistical mechanics framework by directly building a least structured model of the high-dimensional weight space, considering realistic structured data, stochastic gradient descent algorithms, and the computational depth of the network parametrized by weight parameters. We also consider whether the number of network parameters outnumbers the number of supplied training data, namely, over- or under-parametrization. Our least structured model predicts that the weight spaces of the under-parametrization and over-parameterization cases belong to the same class. These weight spaces are well-connected without any heterogeneous geometric properties. In contrast, the shallow-network has a shattered weight space, characterized by discontinuous phase transitions in physics, thereby clarifying roles of depth in deep learning. Our effective model also predicts that inside a deep network, there exists a liquid-like central part of the architecture in the sense that the weights in this part behave as randomly as possible. Our work may thus explain why deep learning is unreasonably effective in terms of the high-dimensional weight space, and how deep networks are different from shallow ones.
Human-Expert-Level Brain Tumor Detection Using Deep Learning with Data Distillation and Augmentation
Lu, Diyuan, Polomac, Nenad, Gacheva, Iskra, Hattingen, Elke, Triesch, Jochen
The application of Deep Learning (DL) for medical diagnosis is often hampered by two problems. First, the amount of training data may be scarce, as it is limited by the number of patients who have acquired the condition to be diagnosed. Second, the training data may be corrupted by various types of noise. Here, we study the problem of brain tumor detection from magnetic resonance spectroscopy (MRS) data, where both types of problems are prominent. To overcome these challenges, we propose a new method for training a deep neural network that distills particularly representative training examples and augments the training data by mixing these samples from one class with those from the same and other classes to create additional training samples. We demonstrate that this technique substantially improves performance, allowing our method to reach human-expert-level accuracy with just a few thousand training examples. Interestingly, the network learns to rely on features of the data that are usually ignored by human experts, suggesting new directions for future research.
Quantization Guided JPEG Artifact Correction
Ehrlich, Max, Davis, Larry, Lim, Ser-Nam, Shrivastava, Abhinav
The JPEG image compression algorithm is the most popular method of image compression because of its ability for large compression ratios. However, to achieve such high compression, information is lost. For aggressive quantization settings, this leads to a noticeable reduction in image quality. Artifact correction has been studied in the context of deep neural networks for some time, but the current methods delivering state-of-the-art results require a different model to be trained for each quality setting, greatly limiting their practical application. We solve this problem by creating a novel architecture which is parameterized by the JPEG files quantization matrix. This allows our single model to achieve state-of-the-art performance over models trained for specific quality settings.... Keywords: JPEG, Discrete Cosine Transform, Artifact Correction, Quantization
Meta-Gradient Reinforcement Learning with an Objective Discovered Online
Xu, Zhongwen, van Hasselt, Hado, Hessel, Matteo, Oh, Junhyuk, Singh, Satinder, Silver, David
Deep reinforcement learning includes a broad family of algorithms that parameterise an internal representation, such as a value function or policy, by a deep neural network. Each algorithm optimises its parameters with respect to an objective, such as Q-learning or policy gradient, that defines its semantics. In this work, we propose an algorithm based on meta-gradient descent that discovers its own objective, flexibly parameterised by a deep neural network, solely from interactive experience with its environment. Over time, this allows the agent to learn how to learn increasingly effectively. Furthermore, because the objective is discovered online, it can adapt to changes over time. We demonstrate that the algorithm discovers how to address several important issues in RL, such as bootstrapping, non-stationarity, and off-policy learning. On the Atari Learning Environment, the meta-gradient algorithm adapts over time to learn with greater efficiency, eventually outperforming the median score of a strong actor-critic baseline.
Everyone should know!! What is Artificial Intelligence?
Amplify_Tech Everyone should Know!! What is Artificial Intelligence? In this video one will get good idea about Artificial Intelligence with practical examples in daily life and branches of Artificial Intelligence- โข #Machine Learning โข #Deep Learning โข #Natural Language Processing โข #Expert System โข #Robotics.
DeepGhost: real-time computational ghost imaging via deep learning
The potential of random pattern based computational ghost imaging (CGI) for real-time applications has been offset by its long image reconstruction time and inefficient reconstruction of complex diverse scenes. To overcome these problems, we propose a fast image reconstruction framework for CGI, called โDeepGhostโ, using deep convolutional autoencoder network to achieve real-time imaging at very low sampling rates (10โ20%). By transferring prior-knowledge from STL-10 dataset to physical-data driven network, the proposed framework can reconstruct complex unseen targets with high accuracy. The experimental results show that the proposed method outperforms existing deep learning and state-of-the-art compressed sensing methods used for ghost imaging under similar conditions. The proposed method employs deep architecture with fast computation, and tackles the shortcomings of existing schemes i.e., inappropriate architecture, training on limited data under controlled settings, and employing shallow network for fast computation.
Generative algorithms are redefining the intersection of software and music โ TechCrunch
What if you could mix and match different tracks from your favorite artists, or create new ones on your own with their voices? This could become a reality sooner than later, as AI models similar to the ones used to create computer-generated art images and embed deepfakes in videos are being increasingly applied to music. The use of algorithms to create music is not new. Researchers used computer programs to generate piano sheet music as far back as the 1950s, and musicians from that era such as Iannis Xenakis and Gottfried Koenig even used them to compose their own music. What has changed are the improvements in generative algorithms, which first gained popularity back in 2014, coupled with large amounts of compute power that are increasingly changing what computers can do with music today.
Exploring AI Cybersecurity, Role of AI and Future of AI in Cybersecurity
AI service providers are bringing together the best machine learning algorithms, NLP applications and Deep Learning methodologies to provide solutions that have foolproof algorithms to detect viruses and malware, often by running pattern recognitions in software. With time, advanced ways AI software and ML implementation in organizations are being tested, with AI algorithms being trained to identify even the smallest malware and ransomware attacks in the system. In several cases the algorithms can even predict future attacks and take necessary action for prevention.