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An Efficient Drifters Deployment Strategy to Evaluate Water Current Velocity Fields

arXiv.org Artificial Intelligence

Water current prediction is essential for understanding ecosystems, and to shed light on the role of the ocean in the global climate context. Solutions vary from physical modeling, and long-term observations, to short-term measurements. In this paper, we consider a common approach for water current prediction that uses Lagrangian floaters for water current prediction by interpolating the trajectory of the elements to reflect the velocity field. Here, an important aspect that has not been addressed before is where to initially deploy the drifting elements such that the acquired velocity field would efficiently represent the water current. To that end, we use a clustering approach that relies on a physical model of the velocity field. Our method segments the modeled map and determines the deployment locations as those that will lead the floaters to 'visit' the center of the different segments. This way, we validate that the area covered by the floaters will capture the in-homogeneously in the velocity field. Exploration over a dataset of velocity field maps that span over a year demonstrates the applicability of our approach, and shows a considerable improvement over the common approach of uniformly randomly choosing the initial deployment sites. Finally, our implementation code can be found in [1].


Machine Learning Develops Fluorescent Tools for Data Encryption

#artificialintelligence

Researchers in Switzerland and Australia have used machine learning to crack the code governing charge transfer and colour emission in chains of molecules. Chains of molecules, known as polymers, can be put together in patterns to create different visual effects, such as emitting a certain colour when exposed to ultraviolet light or other light sources. Polymers are used in data storage, security inks, organic light-emitting diodes (OLEDs), and even the solar energy industry. Until now, getting the molecules in the right order to create the desired effect has been a slow process of trial and error, limiting its practical application and usefulness. To solve this problem, Exciton Science Research Fellow Dr Nastaran Meftahi of RMIT University, under the supervision of Professor Salvy Russo, trained a machine learning model to better understand the behaviour occurring inside and between the molecules.


Mosaic Data Science Combats Climate Change & Accelerates ESG Efforts With Custom Artificial Intelligence & Machine Learning Solutions

#artificialintelligence

LEESBURG, Va., Jan. 09, 2023 (GLOBE NEWSWIRE) -- Mosaic Data Science contributed machine learning algorithm development & deployment services to help a leading power firm automate the process of quantifying the switch to renewable energy portfolios from traditional energy sources while exploring the costs and tradeoffs of said offerings for their business-to-business customers. The solution is designed for enterprises that require power to a diverse set of business functions, such as industrial warehouses, production plants, and related physical infrastructure. The application relies on a highly scalable, custom mathematical optimization algorithm to select the products to eliminate or offset the emissions required to reach the GHG targets. Mosaic's data scientists collaborated with key stakeholders to lay out requirements for an interactive dashboard and the algorithms driving the portfolio recommendations. In the past, this had been a manual, error-prone, and time-consuming effort as sales personnel had to piece together a portfolio to cover energy usage across tens of thousands of service locations for a customer over a multi-decade window.


Spectroscopy and Chemometrics Machine-Learning News Weekly #1, 2023 โ€“ [:en]NIR Calibration Model[:de]NIR Calibration Model[:it]Modelli di Calibrazione NIR

#artificialintelligence

Get the Spectroscopy and Chemometrics News Weekly in real time on Twitter @ CalibModel and follow us. "Foods: Prediction Models for the Content of Calcium, Boron and Potassium in the Fruit of'Huangguan' Pears Established by Using Near-Infrared Spectroscopy" LINK "Construction and Application of Detection Model for Leucine and Tyrosine Content in Golden Tartary Buckwheat Based on Near Infrared Spectroscopy" LINK "Rapid recognition of different sources of methamphetamine drugs based on hand-held near infrared spectroscopy and multi-layer-extreme learning machine algorithms" LINK "Rapid determination of viscosity and viscosity index of lube base oil based on near-infrared spectroscopy and new transformation formula" LINK "Simple dilated convolutional neural network for quantitative modeling based on near infrared spectroscopy techniques" LINK "Fast and nondestructive discrimination of fresh tea leaves at different altitudes based on near infrared spectroscopy and various chemometrics methods" LINK "NIR spectroscopy combined with 1D-convolutional neural network for breast cancerization analysis and diagnosis" LINK "Associations between visceral adipose tissue estimates produced by near-infrared spectroscopy, mobile anthropometrics, and traditional body composition โ€ฆ" LINK "Discrimination of Minced Mutton Adulteration Based on Sized-Adaptive Online NIRS Information and 2D Conventional Neural Network. "Fruit detection research based on near-infrared spectroscopy and lightweight neural network" LINK "Honey quality detection based on near-infrared spectroscopy" LINK "Evaluation of the potential of near infrared hyperspectral imaging for monitoring the invasive brown marmorated stink bug" LINK "Denoising stacked autoencodersbased nearinfrared quality monitoring method via robust samples evaluation" LINK "Visualization research of egg freshness based on hyperspectral imaging and binary competitive adaptive reweighted sampling" LINK "Desert Soil Salinity Inversion Models Based on Field In Situ Spectroscopy in Southern Xinjiang, China" LINK "Novel broad spectral response perovskite solar cells: A review of the current status and advanced strategies for breaking the theoretical limit efficiency" LINK "Remote Sensing: Estimation of Potato Above-Ground Biomass Based on Vegetation Indices and Green-Edge Parameters Obtained from UAVs" LINK "Prognostic value of syntax score, intravascular ultrasound and near-infrared spectroscopy to identify low-risk patients with coronary artery disease 5-year โ€ฆ" LINK


So3krates: Equivariant attention for interactions on arbitrary length-scales in molecular systems

arXiv.org Artificial Intelligence

The application of machine learning methods in quantum chemistry has enabled the study of numerous chemical phenomena, which are computationally intractable with traditional ab-initio methods. However, some quantum mechanical properties of molecules and materials depend on non-local electronic effects, which are often neglected due to the difficulty of modeling them efficiently. This work proposes a modified attention mechanism adapted to the underlying physics, which allows to recover the relevant non-local effects. Namely, we introduce spherical harmonic coordinates (SPHCs) to reflect higher-order geometric information for each atom in a molecule, enabling a non-local formulation of attention in the SPHC space. Our proposed model So3krates - a self-attention based message passing neural network - uncouples geometric information from atomic features, making them independently amenable to attention mechanisms. Thereby we construct spherical filters, which extend the concept of continuous filters in Euclidean space to SPHC space and serve as foundation for a spherical self-attention mechanism. We show that in contrast to other published methods, So3krates is able to describe non-local quantum mechanical effects over arbitrary length scales. Further, we find evidence that the inclusion of higher-order geometric correlations increases data efficiency and improves generalization. So3krates matches or exceeds state-of-the-art performance on popular benchmarks, notably, requiring a significantly lower number of parameters (0.25 - 0.4x) while at the same time giving a substantial speedup (6 - 14x for training and 2 - 11x for inference) compared to other models.


Batch Bayesian Optimization via Particle Gradient Flows

arXiv.org Artificial Intelligence

Bayesian Optimisation (BO) methods seek to find global optima of objective functions which are only available as a black-box or are expensive to evaluate. Such methods construct a surrogate model for the objective function, quantifying the uncertainty in that surrogate through Bayesian inference. Objective evaluations are sequentially determined by maximising an acquisition function at each step. However, this ancilliary optimisation problem can be highly non-trivial to solve, due to the non-convexity of the acquisition function, particularly in the case of batch Bayesian optimisation, where multiple points are selected in every step. In this work we reformulate batch BO as an optimisation problem over the space of probability measures. We construct a new acquisition function based on multipoint expected improvement which is convex over the space of probability measures. Practical schemes for solving this `inner' optimisation problem arise naturally as gradient flows of this objective function. We demonstrate the efficacy of this new method on different benchmark functions and compare with state-of-the-art batch BO methods.


Differentiable Safe Controller Design through Control Barrier Functions

arXiv.org Artificial Intelligence

Learning-based controllers, such as neural network (NN) controllers, can show high empirical performance but lack formal safety guarantees. To address this issue, control barrier functions (CBFs) have been applied as a safety filter to monitor and modify the outputs of learning-based controllers in order to guarantee the safety of the closed-loop system. However, such modification can be myopic with unpredictable long-term effects. In this work, we propose a safe-by-construction NN controller which employs differentiable CBF-based safety layers, and investigate the performance of safe-by-construction NN controllers in learning-based control. Specifically, two formulations of controllers are compared: one is projection-based and the other relies on our proposed set-theoretic parameterization. Both methods demonstrate improved closed-loop performance over using CBF as a separate safety filter in numerical experiments.


Reservoir Prediction by Machine Learning Methods on The Well Data and Seismic Attributes for Complex Coastal Conditions

arXiv.org Artificial Intelligence

The aim of this work was to predict the probability of the spread of rock formations with hydrocarbon-collecting properties in the studied coastal area using a stack of machine learning algorithms and data augmentation and modification methods. This research develops the direction of machine learning where training is conducted on well data and spatial attributes. Methods for overcoming the limitations of this direction are shown, two methods - augmentation and modification of the well data sample: Spindle and Revers-Calibration. Considering the difficulties for seismic data interpretation in coastal area conditions, the proposed approach is a tool which is able to work with the whole totality of geological and geophysical data, extract the knowledge from 159-dimensional space spatial attributes and make facies spreading prediction with acceptable quality - F1 measure for reservoir class 0.798 on average for evaluation of "drilling" results of different geological conditions. It was shown that consistent application of the proposed augmentation methods in the implemented technology stack improves the quality of reservoir prediction by a factor of 1.56 relative to the original dataset.


Safer Together: Machine Learning Models Trained on Shared Accident Datasets Predict Construction Injuries Better than Company-Specific Models

arXiv.org Artificial Intelligence

In this study, we capitalized on a collective dataset repository of 57k accidents from 9 companies belonging to 3 domains and tested whether models trained on multiple datasets (generic models) predicted safety outcomes better than the company-specific models. We experimented with full generic models (trained on all data), per-domain generic models (construction, electric T&D, oil & gas), and with ensembles of generic and specific models. Results are very positive, with generic models outperforming the company-specific models in most cases while also generating finer-grained, hence more useful, forecasts. Successful generic models remove the needs for training company-specific models, saving a lot of time and resources, and give small companies, whose accident datasets are too limited to train their own models, access to safety outcome predictions. It may still however be advantageous to train specific models to get an extra boost in performance through ensembling with the generic models. Overall, by learning lessons from a pool of datasets whose accumulated experience far exceeds that of any single company, and making these lessons easily accessible in the form of simple forecasts, generic models tackle the holy grail of safety cross-organizational learning and dissemination in the construction industry.


Physics-separating artificial neural networks for predicting sputtering and thin film deposition of AlN in Ar/N$_2$ discharges on experimental timescales

arXiv.org Artificial Intelligence

Understanding and modeling plasma-surface interactions frame a multi-scale as well as multi-physics problem. Scale-bridging machine learning surface surrogate models have been demonstrated to perceive the fundamental atomic fidelity for the physical vapor deposition of pure metals. However, the immense computational cost of the data-generating simulations render a practical application with predictions on relevant timescales impracticable. This issue is resolved in this work for the sputter deposition of AlN in Ar/N$_2$ discharges by developing a scheme that populates the parameter spaces effectively. Hybrid reactive molecular dynamics / time-stamped force-bias Monte Carlo simulations of randomized plasma-surface interactions / diffusion processes are used to setup a physics-separating artificial neural network. The application of this generic machine learning model to a specific experimental reference case study enables the systematic analysis of the particle flux emission as well as underlying system state (e.g., composition, mass density, stress, point defect structure) evolution within process times of up to 45 minutes.