cloud
Can cloud seeding save us from water bankruptcy?
Can cloud seeding save us from water bankruptcy? We've long tried to control the weather by engineering rainfall. Now such cloud-seeding efforts are escalating, creating conflict between countries and stoking conspiracy theories. On a cold, windy night in November 2025, a quadcopter drone took off from a farm field at the foot of the Bannock mountain range north of Salt Lake City, rising 4000 metres into thick clouds. A fan with anti-icing propellers kicked into action, blowing yellow dust out of a cannister attached to the back of the drone. Cloud-seeding company Rainmaker was trying to fight dust with dust, spreading silver iodide powder to encourage precipitation and end the deadly dust storms plaguing Utah's capital.
Unsupervised Point Cloud Completion and Segmentation by Generative Adversarial Autoencoding Network
Most existing point cloud completion methods assume the input partial point cloud is clean, which is not the case in practice, and are generally based on supervised learning. In this paper, we present an unsupervised generative adversarial autoencoding network, named UGAAN, which completes the partial point cloud contaminated by surroundings from real scenes and cutouts the object simultaneously, only using artificial CAD models as assistance. The generator of UGAAN learns to predict the complete point clouds on real data from both the discriminator and the autoencoding process of artificial data. The latent codes from generator are also fed to discriminator which makes encoder only extract object features rather than noises. We also devise a refiner for generating better complete cloud with a segmentation module to separate the object from background. We train our UGAAN with one real scene dataset and evaluate it with the other two. Extensive experiments and visualization demonstrate our superiority, generalization and robustness. Comparisons against the previous method show that our method achieves the state-of-the-art performance on unsupervised point cloud completion and segmentation on real data.
Sorting out typicality with the inverse moment matrix SOS polynomial
We study a surprising phenomenon related to the representation of a cloud of data points using polynomials. We start with the previously unnoticed empirical observation that, given a collection (a cloud) of data points, the sublevel sets of a certain distinguished polynomial capture the shape of the cloud very accurately. This distinguished polynomial is a sum-of-squares (SOS) derived in a simple manner from the inverse of the empirical moment matrix. In fact, this SOS polynomial is directly related to orthogonal polynomials and the Christoffel function. This allows to generalize and interpret extremality properties of orthogonal polynomials and to provide a mathematical rationale for the observed phenomenon. Among diverse potential applications, we illustrate the relevance of our results on a network intrusion detection task for which we obtain performances similar to existing dedicated methods reported in the literature.
FM-Delta: Lossless Compression for Storing Massive Fine-tuned Foundation Models
Pre-trained foundation models, particularly large language models, have achieved remarkable success and led to massive fine-tuned variants. These models are commonly fine-tuned locally and then uploaded by users to cloud platforms such as HuggingFace for secure storage. However, the huge model number and their billion-level parameters impose heavy storage overhead for cloud with limited resources. Our empirical and theoretical analysis reveals that most fine-tuned models in cloud have a small difference (delta) from their pre-trained models. To this end, we propose a novel lossless compression scheme FM-Delta specifically for storing massive fine-tuned models in cloud.
SafetyNets: Verifiable Execution of Deep Neural Networks on an Untrusted Cloud
Inference using deep neural networks is often outsourced to the cloud since it is a computationally demanding task. However, this raises a fundamental issue of trust. How can a client be sure that the cloud has performed inference correctly? A lazy cloud provider might use a simpler but less accurate model to reduce its own computational load, or worse, maliciously modify the inference results sent to the client. We propose SafetyNets, a framework that enables an untrusted server (the cloud) to provide a client with a short mathematical proof of the correctness of inference tasks that they perform on behalf of the client. Specifically, SafetyNets develops and implements a specialized interactive proof (IP) protocol for verifiable execution of a class of deep neural networks, i.e., those that can be represented as arithmetic circuits. Our empirical results on three-and four-layer deep neural networks demonstrate the run-time costs of SafetyNets for both the client and server are low.
NASA shows how Sahara desert dust spread all over Europe
The dust coated the Alps and caused'blood rain' in England. In the light of the setting sun, the sky forms a veil of Saharan dust over the Wurmberg in Lower Saxony, Germany. Breakthroughs, discoveries, and DIY tips sent six days a week. The wild winds of winter typically bring snow in the Northern Hemisphere. But sometimes, they carry dust .
Amazon's cloud 'hit by two outages caused by AI tools last year'
A technician works at an Amazon Web Services AI datacentre in New Carlisle, Indiana. A technician works at an Amazon Web Services AI datacentre in New Carlisle, Indiana. Amazon's cloud'hit by two outages caused by AI tools last year' Reported issues at Amazon Web Services raise questions about firm's use of artificial intelligence as it cuts staff Amazon's huge cloud computing arm reportedly experienced at least two outages caused by its own artificial intelligence tools, raising questions about the company's embrace of AI as it lays off human employees. A 13-hour interruption to Amazon Web Services' (AWS) operations in December was caused by an AI agent autonomously choosing to "delete and then recreate" a part of its environment, the Financial Times reported. AWS, which provides vital infrastructure for much of the internet, suffered several outages last year.
Atmospheric pollution caused by space junk could be a huge problem
After a Falcon 9 rocket stage burned up in the atmosphere, vaporised lithium and other metals drifted over Europe. A SpaceX rocket that burned up after re-entering the atmosphere unleashed a plume of vaporised metals over Europe, a type of pollution that is expected to increase as spacecraft and satellites multiply. The upper stage of a Falcon 9, which is designed to splash down in the Pacific Ocean for possible re-use, lost control due to engine failure and fell from orbit over the north Atlantic in February 2025. We're finally solving the puzzle of how clouds will affect our climate People across Europe saw fiery debris streaking through the sky, some of which crashed behind a warehouse in Poland. Seeing the news, Robin Wing at the Leibniz Institute of Atmospheric Physics in Germany and his colleagues turned on their lidar, an instrument for atmospheric sensing.