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The lighting requirements are subjective and one light setting cannot work for all. However, there is little work on developing smart lighting algorithms that can adapt to user preferences. To address this gap, this paper uses fuzzy logic and reinforcement learning to develop an adaptive lighting algorithm. In particular, we develop a baseline fuzzy inference system (FIS) using the domain knowledge, generating light recommendation based on a set of intuitive rules. These rules, derived from existing literature, are based on environmental conditions i.e. daily glare index, and user information including age, activity, and chronotype. Through a feedback mechanism, the user interacts with the algorithm, correcting the algorithm output to their preferences. We interpret these corrections as rewards to a Q-learning algorithm, which tunes the FIS parameters online to match the user preferences. The Q-learning is a model-free learning algorithm that learns to act optimally by interacting with the user and the rewards it receives. This allows the proposed algorithm to work in a model-free manner, effectively handling the uncertainties that might arise from the individualistic preferences of users. To the authors' best knowledge, this algorithm is pioneering work in designing intelligent algorithms for personalized lighting control, featuring several elements of novelty, including the number of environmental and user-related inputs, the continuous control of light intensity as opposed to common on/off control, and the ability to learn user preferences. The algorithm is implemented in a real aircraft cabin and is evaluated in an extensive user study. The implementation results demonstrate that the developed algorithm possesses the capability to learn user preferences while successfully adapting to a wide range of environmental conditions and user characteristics. This underscores its viability as a potent solution for intelligent light management, featuring advanced learning capabilities. • Intelligent lighting algorithm with the ability to learn from and adapt to user preferences. • A fuzzy inference system tunes lighting based on environment and user traits. • The developed algorithm is tested and verified via an in-depth user study. [ABSTRACT FROM AUTHOR]

Grid-interactive building control poses a critical challenge in the context of grid modernization and decarbonization. Recently, various artificial intelligence-based optimal control approaches have been proposed, providing innovative solutions to optimal building control problems. However, researchers and practitioners are now confronted with a dilemma when selecting appropriate control strategies, ranging from model-based (knowledge-incorporating) to learning-based (data-driven) approaches, and hybrid methods combining them. Although each algorithm in existing literature claims superiority over specific baselines, their performance has never been systematically compared and analyzed, owing to the absence of a unified platform for comprehensive evaluation. To fill this knowledge gap, we identify and implement all state-of-the-art approaches within a modular training and evaluation framework, assessing their efficacy in a grid-interactive building control problem. In this paper, we also introduce a streamlined hybrid method that complements existing hybrid approaches. Our comparative study reveals and quantifies the advantages of hybrid methods: on average, they achieve near-optimal control while requiring less than 14% of the online computation of traditional model-based methods. To achieve this performance, they need as few as 2% of the training samples of purely learning-based methods. Finally, we provide insights into the merits, limitations, and implementation of each method to help researchers better understand the state of the art and future directions. The software framework implemented in this study is open-sourced to facilitate future research. [ABSTRACT FROM AUTHOR]

Aeroengine fault detection is an important means to ensure flight safety. The application premise of data driven fault detection method is that all data come from the same distribution. However, this assumption is invalid in the actual engine fault detection, because the engine state will change with the increase of operating time, and the collected data will also have distribution differences. Due to the high cost of collecting engine data, it is difficult to collect enough data from the current state. Fortunately, transfer learning can transfer data information from other fields to the target field, thus alleviating the problem of data scarcity in the target domain. Therefore, from the idea of transfer learning, this paper proposes a cross domain aeroengine fault detection method, viz. transfer learning based on kernel perception algorithm with uneven margins (TL-KPAUM). The proposed method is divided into two stages. In the first stage, KPAUM is trained using the data in the source domain to extract the information in the source domain. In the second stage, the data in the target domain is used to realize the adaptation to the target domain. Compared with several baseline methods, TL-KPAUM has better performance when the amount of data in the target domain is small. Finally, using the simulation data of turbofan engine, the fault detection experiments of degraded state are designed, and the results show that this method is effective. [Display omitted] • A transfer learning algorithm is proposed for aeroengine fault detection. • The proposed method is applied to engine fault detection in different domains. • Simulation results show the effectiveness of this method compared with other methods. • The proposed method has good performance in the case of sparse data in the target domain. [ABSTRACT FROM AUTHOR]

Deep Reinforcement Learning systems are now a hot topic in Machine Learning for their effectiveness in many complex tasks, but their application in safety-critical domains (e.g., robot control or self-autonomous driving) remains dangerous without mechanism to detect and prevent risk situations. In Deep RL, such risk is mostly in the form of adversarial attacks, which introduce small perturbations to sensor inputs with the aim of changing the network-based decisions and thus cause catastrophic situations. In the light of these dangers, a promising line of research is that of providing these Deep RL algorithms with suitable defenses, especially when deploying in real environments. This paper suggests that this line of research could be greatly improved by the concepts from the existing research field of Safe Reinforcement Learning, which has been postulated as a family of RL algorithms capable of providing defenses against many forms of risks. However, the connections between Safe RL and the design of defenses against adversarial attacks in Deep RL remain largely unexplored. This paper seeks to explore precisely some of these connections. In particular, this paper proposes to reuse some of the concepts from existing Safe RL algorithms to create a novel and effective instance-based defense for the deployment stage of Deep RL policies. The proposed algorithm uses a risk function based on how far a state is from the state space known by the agent, that allows identifying and preventing adversarial situations. The success of the proposed defense has been evaluated in 4 Atari games. [ABSTRACT FROM AUTHOR]

Hyperparameter optimization is critical for the performance of machine learning algorithms. Significant efforts have been dedicated to improve the final accuracy of algorithm by hyperparameter tuning. However, some indicators (such as latency, cpu utilization) are also very important in the actual environment. In this paper, we propose a novel method EMORL (E ffective M ulti- O bjective R einforcement L earning) based on multi-objective reinforcement learning for hyperparameter optimization to solve the above limitations. Specifically, we extend hyperparameter optimization problem to the reinforcement learning framework and employ an agent to select hyperparameters sequentially, and design a scalarization function that combines accuracy and latency as a multi-objective reward to guide the policy update. To improve the efficiency of hyperparameter optimization, previously successful configuration is reused for reshaping the advantage function. In the experiment, we apply the proposed method to tune the hyperparameters of the eXtreme Gradient Boosting on 101 tasks and convolutional neural networks on 2 tasks. The experimental results demonstrate that the proposed method is better than other methods in most tasks, especially in terms of latency. In addition, we verify the various components of the proposed method through ablation experiments. [ABSTRACT FROM AUTHOR]