Energy
Seismic Data Interpolation based on Denoising Diffusion Implicit Models with Resampling
Wei, Xiaoli, Zhang, Chunxia, Wang, Hongtao, Tan, Chengli, Xiong, Deng, Jiang, Baisong, Zhang, Jiangshe, Kim, Sang-Woon
The incompleteness of the seismic data caused by missing traces along the spatial extension is a common issue in seismic acquisition due to the existence of obstacles and economic constraints, which severely impairs the imaging quality of subsurface geological structures. Recently, deep learningbased seismic interpolation methods have attained promising progress, while achieving stable training of generative adversarial networks is not easy, and performance degradation is usually notable if the missing patterns in the testing and training do not match. In this paper, we propose a novel seismic denoising diffusion implicit model with resampling. The model training is established on the denoising diffusion probabilistic model, where U-Net is equipped with the multi-head self-attention to match the noise in each step. The cosine noise schedule, serving as the global noise configuration, promotes the high utilization of known trace information by accelerating the passage of the excessive noise stages. The model inference utilizes the denoising diffusion implicit model, conditioning on the known traces, to enable high-quality interpolation with fewer diffusion steps. To enhance the coherency between the known traces and the missing traces within each reverse step, the inference process integrates a resampling strategy to achieve an information recap on the former interpolated traces. Extensive experiments conducted on synthetic and field seismic data validate the superiority of our model and its robustness to various missing patterns. In addition, uncertainty quantification and ablation studies are also investigated.
A Novel Bayes' Theorem for Upper Probabilities
Caprio, Michele, Sale, Yusuf, Hüllermeier, Eyke, Lee, Insup
In their seminal 1990 paper, Wasserman and Kadane establish an upper bound for the Bayes' posterior probability of a measurable set $A$, when the prior lies in a class of probability measures $\mathcal{P}$ and the likelihood is precise. They also give a sufficient condition for such upper bound to hold with equality. In this paper, we introduce a generalization of their result by additionally addressing uncertainty related to the likelihood. We give an upper bound for the posterior probability when both the prior and the likelihood belong to a set of probabilities. Furthermore, we give a sufficient condition for this upper bound to become an equality. This result is interesting on its own, and has the potential of being applied to various fields of engineering (e.g. model predictive control), machine learning, and artificial intelligence.
ChatGPT and Bard Responses to Polarizing Questions
Goyal, Abhay, Siddique, Muhammad, Parekh, Nimay, Schwitzky, Zach, Broekaert, Clara, Michelotti, Connor, Wong, Allie, Cheung, Lam Yin, Hanlon, Robin O, Cheung, Lam Yin, De Choudhury, Munmun, Lee, Roy Ka-Wei, Kumar, Navin
Recent developments in natural language processing have demonstrated the potential of large language models (LLMs) to improve a range of educational and learning outcomes. Of recent chatbots based on LLMs, ChatGPT and Bard have made it clear that artificial intelligence (AI) technology will have significant implications on the way we obtain and search for information. However, these tools sometimes produce text that is convincing, but often incorrect, known as hallucinations. As such, their use can distort scientific facts and spread misinformation. To counter polarizing responses on these tools, it is critical to provide an overview of such responses so stakeholders can determine which topics tend to produce more contentious responses -- key to developing targeted regulatory policy and interventions. In addition, there currently exists no annotated dataset of ChatGPT and Bard responses around possibly polarizing topics, central to the above aims. We address the indicated issues through the following contribution: Focusing on highly polarizing topics in the US, we created and described a dataset of ChatGPT and Bard responses. Broadly, our results indicated a left-leaning bias for both ChatGPT and Bard, with Bard more likely to provide responses around polarizing topics. Bard seemed to have fewer guardrails around controversial topics, and appeared more willing to provide comprehensive, and somewhat human-like responses. Bard may thus be more likely abused by malicious actors. Stakeholders may utilize our findings to mitigate misinformative and/or polarizing responses from LLMs
Aeolus Ocean -- A simulation environment for the autonomous COLREG-compliant navigation of Unmanned Surface Vehicles using Deep Reinforcement Learning and Maritime Object Detection
Vekinis, Andrew Alexander, Perantonis, Stavros
Heading towards navigational autonomy in unmanned surface vehicles (USVs) in the maritime sector can fundamentally lead towards safer waters as well as reduced operating costs, while also providing a range of exciting new capabilities for oceanic research, exploration and monitoring. However, achieving such a goal is challenging. USV control systems must, safely and reliably, be able to adhere to the international regulations for preventing collisions at sea (COLREGs) in encounters with other vessels as they navigate to a given waypoint while being affected by realistic weather conditions, either during the day or at night. To deal with the multitude of possible scenarios, it is critical to have a virtual environment that is able to replicate the realistic operating conditions USVs will encounter, before they can be implemented in the real world. Such "digital twins" form the foundations upon which Deep Reinforcement Learning (DRL) and Computer Vision (CV) algorithms can be used to develop and guide USV control systems. In this paper we describe the novel development of a COLREG-compliant DRL-based collision avoidant navigational system with CV-based awareness in a realistic ocean simulation environment. The performance of the trained autonomous Agents resulting from this approach is evaluated in several successful navigations to set waypoints in both open sea and coastal encounters with other vessels. A binary executable version of the simulator with trained agents is available at https://github.com/aavek/Aeolus-Ocean
Multivariate Time Series characterization and forecasting of VoIP traffic in real mobile networks
Di Mauro, Mario, Galatro, Giovanni, Postiglione, Fabio, Song, Wei, Liotta, Antonio
Predicting the behavior of real-time traffic (e.g., VoIP) in mobility scenarios could help the operators to better plan their network infrastructures and to optimize the allocation of resources. Accordingly, in this work the authors propose a forecasting analysis of crucial QoS/QoE descriptors (some of which neglected in the technical literature) of VoIP traffic in a real mobile environment. The problem is formulated in terms of a multivariate time series analysis. Such a formalization allows to discover and model the temporal relationships among various descriptors and to forecast their behaviors for future periods. Techniques such as Vector Autoregressive models and machine learning (deep-based and tree-based) approaches are employed and compared in terms of performance and time complexity, by reframing the multivariate time series problem into a supervised learning one. Moreover, a series of auxiliary analyses (stationarity, orthogonal impulse responses, etc.) are performed to discover the analytical structure of the time series and to provide deep insights about their relationships. The whole theoretical analysis has an experimental counterpart since a set of trials across a real-world LTE-Advanced environment has been performed to collect, post-process and analyze about 600,000 voice packets, organized per flow and differentiated per codec.
Regression-Oriented Knowledge Distillation for Lightweight Ship Orientation Angle Prediction with Optical Remote Sensing Images
Shi, Zhan, Ding, Xin, Ding, Peng, Yang, Chun, Huang, Ru, Song, Xiaoxuan
Ship orientation angle prediction (SOAP) with optical remote sensing images is an important image processing task, which often relies on deep convolutional neural networks (CNNs) to make accurate predictions. This paper proposes a novel framework to reduce the model sizes and computational costs of SOAP models without harming prediction accuracy. First, a new SOAP model called Mobile-SOAP is designed based on MobileNetV2, achieving state-of-the-art prediction accuracy. Four tiny SOAP models are also created by replacing the convolutional blocks in Mobile-SOAP with four small-scale networks, respectively. Then, to transfer knowledge from Mobile-SOAP to four lightweight models, we propose a novel knowledge distillation (KD) framework termed SOAP-KD consisting of a novel feature-based guidance loss and an optimized synthetic samples-based knowledge transfer mechanism. Lastly, extensive experiments on the FGSC-23 dataset confirm the superiority of Mobile-SOAP over existing models and also demonstrate the effectiveness of SOAP-KD in improving the prediction performance of four specially designed tiny models. Notably, by using SOAP-KD, the test mean absolute error of the ShuffleNetV2x1.0-based model is only 8% higher than that of Mobile-SOAP, but its number of parameters and multiply-accumulate operations (MACs) are respectively 61.6% and 60.8% less.
Energy-efficient Deployment of Deep Learning Applications on Cortex-M based Microcontrollers using Deep Compression
Deutel, Mark, Woller, Philipp, Mutschler, Christopher, Teich, Jürgen
Large Deep Neural Networks (DNNs) are the backbone of today's artificial intelligence due to their ability to make accurate predictions when trained on large data sets. With advancing technologies such as the Internet of Things, interpreting large amounts of data generated by sensors is becoming an increasingly important task. However, in many applications, not only the predictive performance but also the energy consumption of deep learning models is of great interest. This paper investigates the efficient deployment of deep learning models on resource-constrained microcontroller architectures via network compression. We present a methodology for systematically exploring different DNN pruning, quantization, and deployment strategies for different microcontroller architectures, with a focus on lowpower ARM Cortex-M-based systems. The exploration allows to analyze trade-offs between key metrics such as accuracy, memory consumption, execution time, and power consumption. We discuss experimental results on three different DNN architectures and show that we can compress them to less than 10% of their original parameter count before their prediction quality degrades. This also allows us to deploy and evaluate them on Cortex-M based microcontrollers.
Apple insider tells DailyMail.com the iPhone 15 will have 'AI functionality'
An Apple expert revealed the upcoming iPhone 15 will be a game-changer, so much the 250 million iOS users who have not upgraded in four years will run to grab one. Dan Ives, an industry insider with Wedbush Securities, predicts the new smartphone will have more battery power, better camera tech, a new design, and a $100 to $200 increase. The managing director believes the Health app could have AI capabilities to improve data collection on heart rate, breathing and sleeping. And there might be a separate App Store dedicated to AI-powered apps. AI powers Apple's Siri, but the tech giant has yet to add the tech to other aspects of its devices - putting it behind the likes of Google, which added the software to its Pixel cameras.
Recurrent Equilibrium Networks: Flexible Dynamic Models with Guaranteed Stability and Robustness
Revay, Max, Wang, Ruigang, Manchester, Ian R.
This paper introduces recurrent equilibrium networks (RENs), a new class of nonlinear dynamical models} for applications in machine learning, system identification and control. The new model class admits ``built in'' behavioural guarantees of stability and robustness. All models in the proposed class are contracting -- a strong form of nonlinear stability -- and models can satisfy prescribed incremental integral quadratic constraints (IQC), including Lipschitz bounds and incremental passivity. RENs are otherwise very flexible: they can represent all stable linear systems, all previously-known sets of contracting recurrent neural networks and echo state networks, all deep feedforward neural networks, and all stable Wiener/Hammerstein models, and can approximate all fading-memory and contracting nonlinear systems. RENs are parameterized directly by a vector in R^N, i.e. stability and robustness are ensured without parameter constraints, which simplifies learning since \HL{generic methods for unconstrained optimization such as stochastic gradient descent and its variants can be used}. The performance and robustness of the new model set is evaluated on benchmark nonlinear system identification problems, and the paper also presents applications in data-driven nonlinear observer design and control with stability guarantees.
FR3D: Three-dimensional Flow Reconstruction and Force Estimation for Unsteady Flows Around Extruded Bluff Bodies via Conformal Mapping Aided Convolutional Autoencoders
Özbay, Ali Girayhan, Laizet, Sylvain
Since typical experiments in fluids involve only point measurements of the flow via simple and inexpensive methods such as pitot tubes, FR techniques can provide researchers additional insight into flows when more advanced techniques such as particle image velocimetry (PIV) are not available. Various statistical tools have been applied to FR such as linear stochastic estimation (LSE) [1], gappy proper orthogonal decomposition (gappy POD) [2], extended proper orthogonal decomposition (EPOD) [3], and sparse representation [4]. Though these techniques are time-tested and have been applied in practical experiments, for instance to estimate and control the flow in a backward-facing step case via LSE [5], their linear nature limit their capability to deal with complex flows. Neural networks, owing to their universal approximation capabilities [6], are capable of learning arbitrary non-linear and high-dimensional relationships in datasets. This capability makes them very attractive for FR tasks. As a result, the recent explosion of interest in neural networks (NNs) - enabled by substantial increases in computing power, theoretical advances, and the availability of open-source deep learning software - has coincided with a shift towards NN-based FR, and substantial strides were made recently with the application of NNs to the field. Notably, Erichson et al. [7] produced a seminal study exploring the usage of neural networks to reconstruct flows past cylinders. A number of works followed Erichson et al., a selection of which are presented: Fukami et al. [8] demonstrated that NN-based methods can outperform linear FR methods for the reconstruction of flows past cylinders and flapped airfoils [9], and also coupled NN-based FR with Voronoi tessellations to achieve flexibility in terms of the sensor setup [8]. Sun and Wang [10] investigated the application of physics-informed Bayesian NNs in FR, demonstrating high robustness to noise when reconstructing flows in simulated vascular structures.