Energy
Everything You Need to Know About the WIRED & Octopus Energy Tech Summit 2024
Get ready for the return of the annual energy summit in Berlin on October 10. Returning for its second edition this October in Berlin, the WIRED & Octopus Energy Tech Summit is bringing together Europe's leading experts and visionaries in the green energy sector to explore how to accelerate the creation of a fully carbon-free energy system. Last year's summit focused on the urgent need for green technology in the wake of the energy crisis. Audiences heard from business leaders, startup founders, politicians, inventors, and even an astronaut. This year, energy leaders from across the EU will meet to carve the path to a rapid global energy transition.
I'm pretty sure I saw a UFO last night โฆ here's my story
Sponsored Content I'm pretty sure I saw a UFO last night here's my story These binoculars have a built-in camera and are only $99.99. We may earn revenue from the products available on this page and participate in affiliate programs. It sounds insane, but I know what I saw--a UFO. Too many people have drones these days, so I guess it could've been anything. Alas, I was sitting on my porch, enjoying my new pair of night vision binoculars, when I saw something moving in the dark.
How AI can help spot wildfires
New technologies could detect fires faster, giving first responders a head start. In February 2024, a broken utility pole brought down power lines near the small town of Stinnett, Texas. In the following weeks, the fire reportedly sparked by that equipment grew to burn over 1 million acres, the biggest wildfire in the state's history. The full FireSat system should be able to detect tiny fires anywhere in the world, and provide updated images every 20 minutes. Anything from stray fireworks to lightning strikes can start a wildfire. While it's natural for many ecosystems to see some level of fire activity, the hotter, drier conditions brought on by climate change are fueling longer fire seasons with larger fires that burn more land.
Representing Positional Information in Generative World Models for Object Manipulation
Ferraro, Stefano, Mazzaglia, Pietro, Verbelen, Tim, Dhoedt, Bart, Rajeswar, Sai
Object manipulation capabilities are essential skills that set apart embodied agents engaging with the world, especially in the realm of robotics. The ability to predict outcomes of interactions with objects is paramount in this setting. While model-based control methods have started to be employed for tackling manipulation tasks, they have faced challenges in accurately manipulating objects. As we analyze the causes of this limitation, we identify the cause of underperformance in the way current world models represent crucial positional information, especially about the target's goal specification for object positioning tasks. We introduce a general approach that empowers world model-based agents to effectively solve object-positioning tasks. We propose two declinations of this approach for generative world models: position-conditioned (PCP) and latent-conditioned (LCP) policy learning. In particular, LCP employs object-centric latent representations that explicitly capture object positional information for goal specification. This naturally leads to the emergence of multimodal capabilities, enabling the specification of goals through spatial coordinates or a visual goal. Our methods are rigorously evaluated across several manipulation environments, showing favorable performance compared to current model-based control approaches.
Galileo: A Pseudospectral Collocation Framework for Legged Robots
Chandler, Ethan, Jaitly, Akshay, Agheli, Mahdi
Dynamic maneuvers for legged robots present a difficult challenge due to the complex dynamics and contact constraints. This paper introduces a versatile trajectory optimization framework for continuous-time multi-phase problems. We introduce a new transcription scheme that enables pseudospectral collocation to optimize directly on Lie Groups, such as SE(3) and quaternions without special normalization constraints. The key insight is the change of variables - we choose to optimize over the history of the tangent vectors rather than the states themselves. Our approach uses a modified Legendre-Gauss-Radau (LGR) method to produce dynamic motions for various legged robots. We implement our approach as a Model Predictive Controller (MPC) and track the MPC output using a Quadratic Program (QP) based whole-body controller. Results on the Go1 Unitree and WPI HURON humanoid confirm the feasibility of the planned trajectories.
Machine-learning-based multipoint optimization of fluidic injection parameters for improving nozzle performance
Yang, Yunjia, Li, Jiazhe, Zhang, Yufei, Chen, Haixin
Fluidic injection provides a promising solution to improve the performance of overexpanded single expansion ramp nozzle (SERN) during vehicle acceleration. However, determining the injection parameters for the best overall performance under multiple nozzle operating conditions is still a challenge. The gradient-based optimization method requires gradients of injection parameters at each design point, leading to high computational costs if traditional computational fluid dynamic (CFD) simulations are adopted. This paper uses a pretrained neural network model to replace CFD during optimization to quickly calculate the nozzle flow field at multiple design points. Considering the physical characteristics of the nozzle flow field, a prior-based prediction strategy is adopted to enhance the model's transferability. In addition, the back-propagation algorithm of the neural network is adopted to quickly evaluate the gradients by calling the computation process only once, thereby greatly reducing the gradient computation time compared to the finite differential method. As a test case, the average nozzle thrust coefficient of a SERN at seven design points is optimized. An improvement in the thrust coefficient of 1.14% is achieved, and the time cost is greatly reduced compared with the traditional optimization methods, even when the time to establish the database for training is considered.
Rapid aerodynamic prediction of swept wings via physics-embedded transfer learning
Yang, Yunjia, Li, Runze, Zhang, Yufei, Lu, Lu, Chen, Haixin
Machine learning-based models provide a promising way to rapidly acquire transonic swept wing flow fields but suffer from large computational costs in establishing training datasets. Here, we propose a physics-embedded transfer learning framework to efficiently train the model by leveraging the idea that a three-dimensional flow field around wings can be analyzed with two-dimensional flow fields around cross-sectional airfoils. An airfoil aerodynamics prediction model is pretrained with airfoil samples. Then, an airfoil-to-wing transfer model is fine-tuned with a few wing samples to predict three-dimensional flow fields based on two-dimensional results on each spanwise cross section. Sweep theory is embedded when determining the corresponding airfoil geometry and operating conditions, and to obtain the sectional airfoil lift coefficient, which is one of the operating conditions, the low-fidelity vortex lattice method and data-driven methods are proposed and evaluated. Compared to a nontransfer model, introducing the pretrained model reduces the error by 30%, while introducing sweep theory further reduces the error by 9%. When reducing the dataset size, less than half of the wing training samples are need to reach the same error level as the nontransfer framework, which makes establishing the model much easier.
Disentangling Recognition and Decision Regrets in Image-Based Reinforcement Learning
Hรผyรผk, Alihan, Koblitz, Arndt Ryo, Mohajeri, Atefeh, Andrews, Matthew
In image-based reinforcement learning (RL), policies usually operate in two steps: first extracting lower-dimensional features from raw images (the "recognition" step), and then taking actions based on the extracted features (the "decision" step). Extracting features that are spuriously correlated with performance or irrelevant for decision-making can lead to poor generalization performance, known as observational overfitting in image-based RL. In such cases, it can be hard to quantify how much of the error can be attributed to poor feature extraction vs. poor decision-making. In order to disentangle the two sources of error, we introduce the notions of recognition regret and decision regret. Using these notions, we characterize and disambiguate the two distinct causes behind observational overfitting: over-specific representations, which include features that are not needed for optimal decision-making (leading to high decision regret), vs. under-specific representations, which only include a limited set of features that were spuriously correlated with performance during training (leading to high recognition regret). Finally, we provide illustrative examples of observational overfitting due to both over-specific and under-specific representations in maze environments as well as the Atari game Pong.
Evolution and challenges of computer vision and deep learning technologies for analysing mixed construction and demolition waste
Langley, Adrian, Lonergan, Matthew, Huang, Tao, Azghadi, Mostafa Rahimi
Improving the automatic and timely recognition of construction and demolition waste (C&DW) composition is crucial for enhancing business returns, economic outcomes, and sustainability. Technologies like computer vision, artificial intelligence (AI), robotics, and internet of things (IoT) are increasingly integrated into waste processing to achieve these goals. While deep learning (DL) models show promise in recognising homogeneous C&DW piles, few studies assess their performance with mixed, highly contaminated material in commercial settings. Drawing on extensive experience at a C&DW materials recovery facility (MRF) in Sydney, Australia, we explore the challenges and opportunities in developing an advanced automated mixed C&DW management system. We begin with an overview of the evolution of waste management in the construction industry, highlighting its environmental, economic, and societal impacts. We review various C&DW analysis techniques, concluding that DL-based visual methods are the optimal solution. Additionally, we examine the progression of sensor and camera technologies for C&DW analysis as well as the evolution of DL algorithms focused on object detection and material segmentation. We also discuss C&DW datasets, their curation, and innovative methods for their creation. Finally, we share insights on C&DW visual analysis, addressing technical and commercial challenges, research trends, and future directions for mixed C&DW analysis. This paper aims to improve the efficiency of C&DW management by providing valuable insights for ongoing and future research and development efforts in this critical sector.
Unsupervised Attention-Based Multi-Source Domain Adaptation Framework for Drift Compensation in Electronic Nose Systems
Zhang, Wenwen, Hu, Shuhao, Zhang, Zhengyuan, Zheng, Yuanjin, Wang, Qi Jie, Lin, Zhiping
Continuous, long-term monitoring of hazardous, noxious, explosive, and flammable gases in industrial environments using electronic nose (E-nose) systems faces the significant challenge of reduced gas identification accuracy due to time-varying drift in gas sensors. To address this issue, we propose a novel unsupervised attention-based multi-source domain shared-private feature fusion adaptation (AMDS-PFFA) framework for gas identification with drift compensation in E-nose systems. The AMDS-PFFA model effectively leverages labeled data from multiple source domains collected during the initial stage to accurately identify gases in unlabeled gas sensor array drift signals from the target domain. To validate the model's effectiveness, extensive experimental evaluations were conducted using both the University of California, Irvine (UCI) standard drift gas dataset, collected over 36 months, and drift signal data from our self-developed E-nose system, spanning 30 months. Compared to recent drift compensation methods, the AMDS-PFFA model achieves the highest average gas recognition accuracy with strong convergence, attaining 83.20% on the UCI dataset and 93.96% on data from our self-developed E-nose system across all target domain batches. These results demonstrate the superior performance of the AMDS-PFFA model in gas identification with drift compensation, significantly outperforming existing methods.