Energy
La veille de la cybersécurité
When a lifelike, Hanson Robotics robot named Sophia[1] was asked whether she would destroy humans, it replied, "Okay, I will destroy humans." Philip K Dick, another humanoid robot, has promised to keep humans "warm and safe in my people zoo." And Bina48, another lifelike robot, has expressed that it wants "to take over all the nukes." All of these robots were powered by artificial intelligence (AI)--algorithms that learn from data, make decisions, and perform tasks without human input or even, in some cases, human understanding. And while none of these AIs have followed through with their nefarious plots, some scientists, including the (late) physicist Stephen Hawking, have warned that super-intelligent, AI-powered computers could harbor and achieve goals that conflict with human life.
Physics-informed neural networks for non-Newtonian fluid thermo-mechanical problems: an application to rubber calendering process
Nguyen, Thi Nguyen Khoa, Dairay, Thibault, Meunier, Raphaël, Mougeot, Mathilde
Physics-Informed Neural Networks (PINNs) have gained much attention in various fields of engineering thanks to their capability of incorporating physical laws into the models. However, the assessment of PINNs in industrial applications involving coupling between mechanical and thermal fields is still an active research topic. In this work, we present an application of PINNs to a non-Newtonian fluid thermo-mechanical problem which is often considered in the rubber calendering process. We demonstrate the effectiveness of PINNs when dealing with inverse and ill-posed problems, which are impractical to be solved by classical numerical discretization methods. We study the impact of the placement of the sensors and the distribution of unsupervised points on the performance of PINNs in a problem of inferring hidden physical fields from some partial data. We also investigate the capability of PINNs to identify unknown physical parameters from the measurements captured by sensors. The effect of noisy measurements is also considered throughout this work. The results of this paper demonstrate that in the problem of identification, PINNs can successfully estimate the unknown parameters using only the measurements on the sensors. In ill-posed problems where boundary conditions are not completely defined, even though the placement of the sensors and the distribution of unsupervised points have a great impact on PINNs performance, we show that the algorithm is able to infer the hidden physics from local measurements.
Quantification of Deep Neural Network Prediction Uncertainties for VVUQ of Machine Learning Models
Recent performance breakthroughs in Artificial intelligence (AI) and Machine learning (ML), especially advances in Deep learning (DL), the availability of powerful, easy-to-use ML libraries (e.g., scikit-learn, TensorFlow, PyTorch.), and increasing computational power have led to unprecedented interest in AI/ML among nuclear engineers. For physics-based computational models, Verification, Validation and Uncertainty Quantification (VVUQ) have been very widely investigated and a lot of methodologies have been developed. However, VVUQ of ML models has been relatively less studied, especially in nuclear engineering. In this work, we focus on UQ of ML models as a preliminary step of ML VVUQ, more specifically, Deep Neural Networks (DNNs) because they are the most widely used supervised ML algorithm for both regression and classification tasks. This work aims at quantifying the prediction, or approximation uncertainties of DNNs when they are used as surrogate models for expensive physical models. Three techniques for UQ of DNNs are compared, namely Monte Carlo Dropout (MCD), Deep Ensembles (DE) and Bayesian Neural Networks (BNNs). Two nuclear engineering examples are used to benchmark these methods, (1) time-dependent fission gas release data using the Bison code, and (2) void fraction simulation based on the BFBT benchmark using the TRACE code. It was found that the three methods typically require different DNN architectures and hyperparameters to optimize their performance. The UQ results also depend on the amount of training data available and the nature of the data. Overall, all these three methods can provide reasonable estimations of the approximation uncertainties. The uncertainties are generally smaller when the mean predictions are close to the test data, while the BNN methods usually produce larger uncertainties than MCD and DE.
Reduced Optimal Power Flow Using Graph Neural Network
OPF problems are formulated and solved for power system operations, especially for determining generation dispatch points in real-time. For large and complex power system networks with large numbers of variables and constraints, finding the optimal solution for real-time OPF in a timely manner requires a massive amount of computing power. This paper presents a new method to reduce the number of constraints in the original OPF problem using a graph neural network (GNN). GNN is an innovative machine learning model that utilizes features from nodes, edges, and network topology to maximize its performance. In this paper, we proposed a GNN model to predict which lines would be heavily loaded or congested with given load profiles and generation capacities. Only these critical lines will be monitored in an OPF problem, creating a reduced OPF (ROPF) problem. Significant saving in computing time is expected from the proposed ROPF model. A comprehensive analysis of predictions from the GNN model was also made. It is concluded that the application of GNN for ROPF is able to reduce computing time while retaining solution quality.
When Being Soft Makes You Tough: A Collision-Resilient Quadcopter Inspired by Arthropods' Exoskeletons
de Azambuja, Ricardo, Fouad, Hassan, Bouteiller, Yann, Sol, Charles, Beltrame, Giovanni
Flying robots are usually rather delicate and require protective enclosures when facing the risk of collision, while high complexity and reduced payload are recurrent problems with collision-resilient flying robots. Inspired by arthropods' exoskeletons, we design a simple, open source, easily manufactured, semi-rigid structure with soft joints that can withstand high-velocity impacts. With an exoskeleton, the protective shell becomes part of the main robot structure, thereby minimizing its loss in payload capacity. Our design is simple to build and customize using cheap components (e.g. bamboo skewers) and consumer-grade 3D printers. The result is CogniFly, a sub-250g autonomous quadcopter that survives multiple collisions at speeds up to 7m/s. In addition to its collision-resiliency, CogniFly is easy to program using Python or Buzz, carries sensors that allow it to fly for approx. 17min without the need of GPS or an external motion capture system, has enough computing power to run deep neural network models on-board and was designed to facilitate integration with an automated battery swapping system. This structure becomes an ideal platform for high-risk activities (such as flying in a cluttered environment or reinforcement learning training) by dramatically reducing the risks of damaging its own hardware or the environment. Source code, 3D files, instructions and videos are available through the project's website (https://thecognifly.github.io).
Three opportunities of Digital Transformation: AI, IoT and Blockchain
Koomey's law This law posits that the energy efficiency of computation doubles roughly every one-and-a-half years (see Figure 1–7). In other words, the energy necessary for the same amount of computation halves in that time span. To visualize the exponential impact this has, consider the face that a fully charged MacBook Air, when applying the energy efficiency of computation of 1992, would completely drain its battery in a mere 1.5 seconds. According to Koomey's law, the energy requirements for computation in embedded devices is shrinking to the point that harvesting the required energy from ambient sources like solar power and thermal energy should suffice to power the computation necessary in many applications. Metcalfe's law This law has nothing to do with chips, but all to do with connectivity. Formulated by Robert Metcalfe as he invented Ethernet, the law essentially states that the value of a network increases exponentially with regard to the number of its nodes (see Figure 1–8).
Hot Robotics Symposium celebrates UK success
An internationally leading robotics initiative that enables academia and industry to find innovative solutions to real world challenges, celebrated its success with a Hot Robotics Symposium hosted across three UK regions last week. The National Nuclear User Facility (NNUF) for Hot Robotics is a government funded initiative that supports innovation in the nuclear sector by making world-leading testing facilities, sensors and robotic equipment easily accessible to academia and industry. Ground-breaking, impactful research in robotics and artificial intelligence will benefit the UK's development of fusion energy as safe, low carbon and sustainable energy source in addition to adjacent sectors such as nuclear decommissioning, space, and mobile applications. Visitors to UKAEA's RACE (UK Atomic Energy Authority / Remote Applications in Challenging Environments) in Oxfordshire, the University of Bristol facility in Fenswood Farm (North Somerset), and the National Nuclear Laboratory in Cumbria, were treated to a host of robots in action, tours and a packed speaker programme. A combination of robotic manipulators, ground, aerial and underwater vehicles along with deployment robots, plant mock-ups, and supporting infrastructure, were all showcased to demonstrate the breadth of the scheme.
Tensor Recovery Based on A Novel Non-convex Function Minimax Logarithmic Concave Penalty Function
Zhang, Hongbing, Liu, Xinyi, Liu, Chang, Fan, Hongtao, Li, Yajing, Zhu, Xinyun
Non-convex relaxation methods have been widely used in tensor recovery problems, and compared with convex relaxation methods, can achieve better recovery results. In this paper, a new non-convex function, Minimax Logarithmic Concave Penalty (MLCP) function, is proposed, and some of its intrinsic properties are analyzed, among which it is interesting to find that the Logarithmic function is an upper bound of the MLCP function. The proposed function is generalized to tensor cases, yielding tensor MLCP and weighted tensor $L\gamma$-norm. Consider that its explicit solution cannot be obtained when applying it directly to the tensor recovery problem. Therefore, the corresponding equivalence theorems to solve such problem are given, namely, tensor equivalent MLCP theorem and equivalent weighted tensor $L\gamma$-norm theorem. In addition, we propose two EMLCP-based models for classic tensor recovery problems, namely low-rank tensor completion (LRTC) and tensor robust principal component analysis (TRPCA), and design proximal alternate linearization minimization (PALM) algorithms to solve them individually. Furthermore, based on the Kurdyka-{\L}ojasiwicz property, it is proved that the solution sequence of the proposed algorithm has finite length and converges to the critical point globally. Finally, Extensive experiments show that proposed algorithm achieve good results, and it is confirmed that the MLCP function is indeed better than the Logarithmic function in the minimization problem, which is consistent with the analysis of theoretical properties.
Cruise begins charging fares for its driverless taxi service in San Francisco
GM's Cruise has started charging passengers for fully driverless rides in San Francisco. The company secured a driverless deployment permit from the California Public Utilities Commission (CPUC) earlier this month, making it the first in the industry to do so. That allows Cruise to charge for rides with no safety driver behind the wheel, though its vehicles are limited to select streets in the city. In addition, the company's paid passenger service can only operate from 10PM to 6AM, and its cars can only drive at a max speed of 30 mph. Another limitation is that its driverless vehicles aren't allowed on highways and can't operate during times of heavy fog and rain.
Operational Decisioning with AIoT and Intelligent Assets at Enterprise-Scale? IoTPractitioner.com The IoT Portal Platform
Every day, small and large companies alike make strategic and operational decisions that influences the bottom line. Strategic decisions are typically made by the C-suite, and these generally are one-off decisions that are made over time and only after careful study of curated information from several sources and consultation with experts. Examples of strategic decisions include mergers and acquisitions and large capital expenditures. Operational decisions on the other hand are made every day by workers and operations personnel. For small organizations, this can mean dozens, if not hundreds of decisions every day.