Energy
Local Adaptivity of Gradient Boosting in Histogram Transform Ensemble Learning
In this paper, we propose a gradient boosting algorithm called \textit{adaptive boosting histogram transform} (\textit{ABHT}) for regression to illustrate the local adaptivity of gradient boosting algorithms in histogram transform ensemble learning. From the theoretical perspective, when the target function lies in a locally H\"older continuous space, we show that our ABHT can filter out the regions with different orders of smoothness. Consequently, we are able to prove that the upper bound of the convergence rates of ABHT is strictly smaller than the lower bound of \textit{parallel ensemble histogram transform} (\textit{PEHT}). In the experiments, both synthetic and real-world data experiments empirically validate the theoretical results, which demonstrates the advantageous performance and local adaptivity of our ABHT.
Renewable energy integration and microgrid energy trading using multi-agent deep reinforcement learning
Harrold, Daniel J. B., Cao, Jun, Fan, Zhong
In this paper, multi-agent reinforcement learning is used to control a hybrid energy storage system working collaboratively to reduce the energy costs of a microgrid through maximising the value of renewable energy and trading. The agents must learn to control three different types of energy storage system suited for short, medium, and long-term storage under fluctuating demand, dynamic wholesale energy prices, and unpredictable renewable energy generation. Two case studies are considered: the first looking at how the energy storage systems can better integrate renewable energy generation under dynamic pricing, and the second with how those same agents can be used alongside an aggregator agent to sell energy to self-interested external microgrids looking to reduce their own energy bills. This work found that the centralised learning with decentralised execution of the multi-agent deep deterministic policy gradient and its state-of-the-art variants allowed the multi-agent methods to perform significantly better than the control from a single global agent. It was also found that using separate reward functions in the multi-agent approach performed much better than using a single control agent. Being able to trade with the other microgrids, rather than just selling back to the utility grid, also was found to greatly increase the grid's savings.
Building Sustainable AI/ML Solutions in the Cloud with Federated Learning
Global warming is on the rise due to the presence of the highest levels of carbon dioxide, methane, and nitrous oxide levels compared to the past. Data Scientists, data engineers, and cloud experts all have come forward to create a more sustainable environment by following the best practices in Machine Learning. Machine Learning models create a detrimental effect on the environment when using substantial computational resources and energy while getting trained for thousands of hours on specialized hardware accelerators in data centers. The average temperature rise has been increasing steadily over the last 3 decades (from 1980), as illustrated in the figure below. All popular Meteorological agencies/bodies show similar trends, which have made environmentalists, geologists, and technology experts in different domains come forward and set certain standards for controlling the temperature rise.
Active Sensing for Search and Tracking: A Review
Varotto, Luca, Cenedese, Angelo, Cavallaro, Andrea
Active Position Estimation (APE) is the task of localizing one or more targets using one or more sensing platforms. APE is a key task for search and rescue missions, wildlife monitoring, source term estimation, and collaborative mobile robotics. Success in APE depends on the level of cooperation of the sensing platforms, their number, their degrees of freedom and the quality of the information gathered. APE control laws enable active sensing by satisfying either pure-exploitative or pure-explorative criteria. The former minimizes the uncertainty on position estimation; whereas the latter drives the platform closer to its task completion. In this paper, we define the main elements of APE to systematically classify and critically discuss the state of the art in this domain. We also propose a reference framework as a formalism to classify APE-related solutions. Overall, this survey explores the principal challenges and envisages the main research directions in the field of autonomous perception systems for localization tasks. It is also beneficial to promote the development of robust active sensing methods for search and tracking applications.
DNN-based Policies for Stochastic AC OPF
Gupta, Sarthak, Misra, Sidhant, Deka, Deepjyoti, Kekatos, Vassilis
A prominent challenge to the safe and optimal operation of the modern power grid arises due to growing uncertainties in loads and renewables. Stochastic optimal power flow (SOPF) formulations provide a mechanism to handle these uncertainties by computing dispatch decisions and control policies that maintain feasibility under uncertainty. Most SOPF formulations consider simple control policies such as affine policies that are mathematically simple and resemble many policies used in current practice. Motivated by the efficacy of machine learning (ML) algorithms and the potential benefits of general control policies for cost and constraint enforcement, we put forth a deep neural network (DNN)-based policy that predicts the generator dispatch decisions in real time in response to uncertainty. The weights of the DNN are learnt using stochastic primal-dual updates that solve the SOPF without the need for prior generation of training labels and can explicitly account for the feasibility constraints in the SOPF. The advantages of the DNN policy over simpler policies and their efficacy in enforcing safety limits and producing near optimal solutions are demonstrated in the context of a chance constrained formulation on a number of test cases.
Artificial intelligence: Friend or foe for building a better future? - Issuu
In 2015, Elon Musk, Bill Gates and the late Stephen Hawking were rather incongruously nominated for the 2015 Luddite Award -- an honor bestowed by the Information Technology & Information Foundation for "The Worst of the Year's Worst Innovation Killers." Musk, Gates and Hawking -- along with many others -- had expressed growing concerns over the potential risks of naรฏve and irresponsible developments in artificial intelligence, commonly referred to as AI. In spite of their collective technological optimism, the speed of recent advances had them running scared. Six years on, the debate over the potential risks of AI, and how to ensure its ethical and responsible development and use, is fiercer than ever -- so much so that the White House has just committed to developing a "bill of rights" to guard against the inappropriate use of AI and similarly powerful tech. Yet, as with many technology trends, the challenges and opportunities AI presents are more complex than they may at first seem.
Tech Predictions for 2022 and Beyond
We have reached an inflection point. After AWS pioneered cloud technology more than 15 years ago, cloud infrastructure has evolved to a place where we are seeing all parts of the cloud reach practically anywhere on the planet--and even into space. The cloud has allowed what was once science fiction to become science fact. Models and techniques in the artificial intelligence (AI) and machine learning (ML) realm have gotten better and better--so much so that we see glimpses of new kinds of use cases emerging that we previously only imagined in movies and comics. We are entering a phase where data is abundant, access to it is almost instantaneous, and our ability to make sense of it in new and subtle ways is practically automatic.
Controlling Smart Inverters using Proxies: A Chance-Constrained DNN-based Approach
Gupta, Sarthak, Kekatos, Vassilis, Jin, Ming
Coordinating inverters at scale under uncertainty is the desideratum for integrating renewables in distribution grids. Unless load demands and solar generation are telemetered frequently, controlling inverters given approximate grid conditions or proxies thereof becomes a key specification. Although deep neural networks (DNNs) can learn optimal inverter schedules, guaranteeing feasibility is largely elusive. Rather than training DNNs to imitate already computed optimal power flow (OPF) solutions, this work integrates DNN-based inverter policies into the OPF. The proposed DNNs are trained through two OPF alternatives that confine voltage deviations on the average and as a convex restriction of chance constraints. The trained DNNs can be driven by partial, noisy, or proxy descriptors of the current grid conditions. This is important when OPF has to be solved for an unobservable feeder. DNN weights are trained via back-propagation and upon differentiating the AC power flow equations assuming the network model is known. Otherwise, a gradient-free variant is put forth. The latter is relevant when inverters are controlled by an aggregator having access only to a power flow solver or a digital twin of the feeder. Numerical tests compare the DNN-based inverter control schemes with the optimal inverter setpoints in terms of optimality and feasibility.
Graph Neural Networks for Charged Particle Tracking on FPGAs
Elabd, Abdelrahman, Razavimaleki, Vesal, Huang, Shi-Yu, Duarte, Javier, Atkinson, Markus, DeZoort, Gage, Elmer, Peter, Hu, Jin-Xuan, Hsu, Shih-Chieh, Lai, Bo-Cheng, Neubauer, Mark, Ojalvo, Isobel, Thais, Savannah
The determination of charged particle trajectories in collisions at the CERN Large Hadron Collider (LHC) is an important but challenging problem, especially in the high interaction density conditions expected during the future high-luminosity phase of the LHC (HL-LHC). Graph neural networks (GNNs) are a type of geometric deep learning algorithm that has successfully been applied to this task by embedding tracker data as a graph -- nodes represent hits, while edges represent possible track segments -- and classifying the edges as true or fake track segments. However, their study in hardware- or software-based trigger applications has been limited due to their large computational cost. In this paper, we introduce an automated translation workflow, integrated into a broader tool called $\texttt{hls4ml}$, for converting GNNs into firmware for field-programmable gate arrays (FPGAs). We use this translation tool to implement GNNs for charged particle tracking, trained using the TrackML challenge dataset, on FPGAs with designs targeting different graph sizes, task complexites, and latency/throughput requirements. This work could enable the inclusion of charged particle tracking GNNs at the trigger level for HL-LHC experiments.
A Novel Deep Parallel Time-series Relation Network for Fault Diagnosis
Considering the models that apply the contextual information of time-series data could improve the fault diagnosis performance, some neural network structures such as RNN, LSTM, and GRU were proposed to model the industrial process effectively. However, these models are restricted by their serial computation and hence cannot achieve high diagnostic efficiency. Also the parallel CNN is difficult to implement fault diagnosis in an efficient way because it requires larger convolution kernels or deep structure to achieve long-term feature extraction capabilities. Besides, BERT model applies absolute position embedding to introduce contextual information to the model, which would bring noise to the raw data and therefore cannot be applied to fault diagnosis directly. In order to address the above problems, a fault diagnosis model named deep parallel time-series relation network(\textit{DPTRN}) has been proposed in this paper. There are mainly three advantages for DPTRN: (1) Our proposed time relationship unit is based on full multilayer perceptron(\textit{MLP}) structure, therefore, DPTRN performs fault diagnosis in a parallel way and improves computing efficiency significantly. (2) By improving the absolute position embedding, our novel decoupling position embedding unit could be applied on the fault diagnosis directly and learn contextual information. (3) Our proposed DPTRN has obvious advantage in feature interpretability. Our model outperforms other methods on both TE and KDD-CUP99 datasets which confirms the effectiveness, efficiency and interpretability of the proposed DPTRN model.