Materials
Lifelong Machine Learning of Functionally Compositional Structures
A hallmark of human intelligence is the ability to construct self-contained chunks of knowledge and reuse them in novel combinations for solving different problems. Learning such compositional structures has been a challenge for artificial systems, due to the underlying combinatorial search. To date, research into compositional learning has largely proceeded separately from work on lifelong or continual learning. This dissertation integrated these two lines of work to present a general-purpose framework for lifelong learning of functionally compositional structures. The framework separates the learning into two stages: learning how to combine existing components to assimilate a novel problem, and learning how to adapt the existing components to accommodate the new problem. This separation explicitly handles the trade-off between stability and flexibility. This dissertation instantiated the framework into various supervised and reinforcement learning (RL) algorithms. Supervised learning evaluations found that 1) compositional models improve lifelong learning of diverse tasks, 2) the multi-stage process permits lifelong learning of compositional knowledge, and 3) the components learned by the framework represent self-contained and reusable functions. Similar RL evaluations demonstrated that 1) algorithms under the framework accelerate the discovery of high-performing policies, and 2) these algorithms retain or improve performance on previously learned tasks. The dissertation extended one lifelong compositional RL algorithm to the nonstationary setting, where the task distribution varies over time, and found that modularity permits individually tracking changes to different elements in the environment. The final contribution of this dissertation was a new benchmark for compositional RL, which exposed that existing methods struggle to discover the compositional properties of the environment.
SFILES 2.0: An extended text-based flowsheet representation
Vogel, Gabriel, Balhorn, Lukas Schulze, Hirtreiter, Edwin, Schweidtmann, Artur M.
SFILES is a text-based notation for chemical process flowsheets. It was originally proposed by d'Anterroches (2006) who was inspired by the text-based SMILES notation for molecules. The text-based format has several advantages compared to flowsheet images regarding the storage format, computational accessibility, and eventually for data analysis and processing. However, the original SFILES version cannot describe essential flowsheet configurations unambiguously, such as the distinction between top and bottom products. Neither is it capable of describing the control structure required for the safe and reliable operation of chemical processes. Also, there is no publicly available software for decoding or encoding chemical process topologies to SFILES. We propose the SFILES 2.0 with a complete description of the extended notation and naming conventions. Additionally, we provide open-source software for the automated conversion between flowsheet graphs and SFILES 2.0 strings. This way, we hope to encourage researchers and engineers to publish their flowsheet topologies as SFILES 2.0 strings. The ultimate goal is to set the standards for creating a FAIR database of chemical process flowsheets, which would be of great value for future data analysis and processing.
Linking Properties to Microstructure in Liquid Metal Embedded Elastomers via Machine Learning
Anantharanga, Abhijith Thoopul, Hashemi, Mohammad Saber, Sheidaei, Azadeh
Liquid metals (LM) are embedded in an elastomer matrix to obtain soft composites with unique thermal, dielectric, and mechanical properties. They have applications in soft robotics, biomedical engineering, and wearable electronics. By linking the structure to the properties of these materials, it is possible to perform material design rationally. Liquid-metal embedded elastomers (LMEEs) have been designed for targeted electro-thermo-mechanical properties by semi-supervised learning of structure-property (SP) links in a variational autoencoder network (VAE). The design parameters are the microstructural descriptors that are physically meaningful and have affine relationships with the synthetization of the studied particulate composite. The machine learning (ML) model is trained on a generated dataset of microstructural descriptors with their multifunctional property quantities as their labels. Sobol sequence is used for in-silico Design of Experiment (DoE) by sampling the design space to generate a comprehensive dataset of 3D microstructure realizations via a packing algorithm. The mechanical responses of the generated microstructures are simulated using a previously developed Finite Element (FE) model, considering the surface tension induced by LM inclusions, while the linear thermal and dielectric constants are homogenized with the help of our in-house Fast Fourier Transform (FFT) package. Following the training by minimization of an appropriate loss function, the VAE encoder acts as the surrogate of numerical solvers of the multifunctional homogenizations, and its decoder is used for the material design. Our results indicate the satisfactory performance of the surrogate model and the inverse calculator with respect to high-fidelity numerical simulations validated with LMEE experimental results.
Future of farming: AI, IoT, drones, and more (free PDF)
By 2024, the Earth's population will total more than 8 billion for the first time in history, adding new stresses on the global supply chain, which is already challenged by a volatile climate and water supply shortages. To meet future food demands, farmers are implementing innovative tech solutions. For example, IBM researchers are working on solutions that tap artificial intelligence (AI) and Internet of Things (IoT) and cloud-connected devices at every step of the food supply chain. New IoT systems are helping monitor the health of beehives to ensure the security of the world's food supply. Farmers are also implementing new technology such as diagnostic drones, which can disperse pesticide and fertilizer to rice fields in Japan and using AI-enhanced robotic harvesters, complete with enhanced dexterity, to tackle crops of various shapes and sizes.
Operational Excellence with Azure Machine Learning for Mining
Machine Learning and Artificial Intelligence, together with other advanced modelling techniques, are continuously evolving and you can find thousands of algorithms, tools, platforms, etc., making it challenging to identify and validate the correct approach, technologies and solutions to use in the Mining industry. Furthermore, the success of a data analytics solution can only be realized if it can be readily deployed, managed and operated. We look forward to seeing you there.
Uncertainty quantification for predictions of atomistic neural networks
Vazquez-Salazar, Luis Itza, Boittier, Eric D., Meuwly, M.
The value of uncertainty quantification on predictions for trained neural networks (NNs) on quantum chemical reference data is quantitatively explored. For this, the architecture of the PhysNet NN was suitably modified and the resulting model was evaluated with different metrics to quantify calibration, quality of predictions, and whether prediction error and the predicted uncertainty can be correlated. The results from training on the QM9 database and evaluating data from the test set within and outside the distribution indicate that error and uncertainty are not linearly related. The results clarify that noise and redundancy complicate property prediction for molecules even in cases for which changes - e.g. double bond migration in two otherwise identical molecules - are small. The model was then applied to a real database of tautomerization reactions. Analysis of the distance between members in feature space combined with other parameters shows that redundant information in the training dataset can lead to large variances and small errors whereas the presence of similar but unspecific information returns large errors but small variances. This was, e.g., observed for nitro-containing aliphatic chains for which predictions were difficult although the training set contained several examples for nitro groups bound to aromatic molecules. This underlines the importance of the composition of the training data and provides chemical insight into how this affects the prediction capabilities of a ML model. Finally, the approach put forward can be used for information-based improvement of chemical databases for target applications through active learning optimization.
OSU Uses AI to Save Bees - The Corvallis Advocate
Researchers in the Oregon State University College of Engineering have harnessed the power of artificial intelligence to help protect bees from pesticides. Cory Simon, assistant professor of chemical engineering, and Xiaoli Fern, associate professor of computer science, led the project, which involved training a machine learning model to predict whether any proposed new herbicide, fungicide or insecticide would be toxic to honey bees based on the compound’s molecular structure. The findings, featured on the cover of The Journal of Chemical Physics in a […]
Learning physics-informed simulation models for soft robotic manipulation: A case study with dielectric elastomer actuators
Lahariya, Manu, Innes, Craig, Develder, Chris, Ramamoorthy, Subramanian
Soft actuators offer a safe, adaptable approach to tasks like gentle grasping and dexterous manipulation. Creating accurate models to control such systems however is challenging due to the complex physics of deformable materials. Accurate Finite Element Method (FEM) models incur prohibitive computational complexity for closed-loop use. Using a differentiable simulator is an attractive alternative, but their applicability to soft actuators and deformable materials remains underexplored. This paper presents a framework that combines the advantages of both. We learn a differentiable model consisting of a material properties neural network and an analytical dynamics model of the remainder of the manipulation task. This physics-informed model is trained using data generated from FEM, and can be used for closed-loop control and inference. We evaluate our framework on a dielectric elastomer actuator (DEA) coin-pulling task. We simulate the task of using DEA to pull a coin along a surface with frictional contact, using FEM, and evaluate the physics-informed model for simulation, control, and inference. Our model attains < 5% simulation error compared to FEM, and we use it as the basis for an MPC controller that requires fewer iterations to converge than model-free actor-critic, PD, and heuristic policies.
Can we eliminate all of the single-use plastic? - Channel969
A brand new partnership goals to take an enormous chew out of the scourge of single-use plastic. With the assistance of some robots and economies of scale, it is a constructive step in an issue that appears wholly intractable. Compostable packaging firm Zume, which has innovated the manufacture of excessive output molded fiber packaging utilizing robots, is becoming a member of forces with sustainable packaging firm Transcend Packaging. By becoming a member of forces, the businesses try to rally an efficient base of capabilities and distribution to tackle the unfathomable may of the plastics business. At the moment, single-use plastic is a $320B business.