Reinforcement Learning
Cellular Network Capacity and Coverage Enhancement with MDT Data and Deep Reinforcement Learning
Skocaj, Marco, Amorosa, Lorenzo Mario, Ghinamo, Giorgio, Muratore, Giuliano, Micheli, Davide, Zabini, Flavio, Verdone, Roberto
Recent years witnessed a remarkable increase in the availability of data and computing resources in communication networks. This contributed to the rise of data-driven over model-driven algorithms for network automation. This paper investigates a Minimization of Drive Tests (MDT)-driven Deep Reinforcement Learning (DRL) algorithm to optimize coverage and capacity by tuning antennas tilts on a cluster of cells from TIM's cellular network. We jointly utilize MDT data, electromagnetic simulations, and network Key Performance indicators (KPIs) to define a simulated network environment for the training of a Deep Q-Network (DQN) agent. Some tweaks have been introduced to the classical DQN formulation to improve the agent's sample efficiency, stability, and performance. In particular, a custom exploration policy is designed to introduce soft constraints at training time. Results show that the proposed algorithm outperforms baseline approaches like DQN and best-fist search in terms of long-term reward and sample efficiency. Our results indicate that MDT-driven approaches constitute a valuable tool for autonomous coverage and capacity optimization of mobile radio networks.
Blockchain Framework for Artificial Intelligence Computation
Blockchain is an essentially distributed database recording all transactions or digital events among participating parties. Each transaction in the records is approved and verified by consensus of the participants in the system that requires solving a hard mathematical puzzle, which is known as proof-of-work. To make the approved records immutable, the mathematical puzzle is not trivial to solve and therefore consumes substantial computing resources. However, it is energy-wasteful to have many computational nodes installed in the blockchain competing to approve the records by just solving a meaningless puzzle. Here, we pose proof-of-work as a reinforcement-learning problem by modeling the blockchain growing as a Markov decision process, in which a learning agent makes an optimal decision over the environment's state, whereas a new block is added and verified. Specifically, we design the block verification and consensus mechanism as a deep reinforcement-learning iteration process. As a result, our method utilizes the determination of state transition and the randomness of action selection of a Markov decision process, as well as the computational complexity of a deep neural network, collectively to make the blocks not easy to recompute and to preserve the order of transactions, while the blockchain nodes are exploited to train the same deep neural network with different data samples (state-action pairs) in parallel, allowing the model to experience multiple episodes across computing nodes but at one time. Our method is used to design the next generation of public blockchain networks, which has the potential not only to spare computational resources for industrial applications but also to encourage data sharing and AI model design for common problems.
How Artificial Intelligence is Taught to Navigate Oceans
AZoRobotics speaks with Peter Gunnarson from Caltech about his research into using artificial intelligence (AI) to teach autonomous drones to navigate the ocean using ocean currents. An estimated 80% of the ocean is still unexplored, but our current methods for exploring the ocean are often expensive, such as with ship-based observations, or limited in capability, as with buoys. Instead, we are envisioning swarms of smart underwater robots that can navigate on their own, save energy by exploiting ocean currents, find optimal locations to gather data about the ocean and potentially follow and track marine life. This research aims to show how Reinforcement Learning could equip robots with the intelligence needed to accomplish these tasks on their own. With global exploration and sampling of the ocean, we may be able to gain a better understanding of the physics of the ocean and climate change.
A Globally Convergent Evolutionary Strategy for Stochastic Constrained Optimization with Applications to Reinforcement Learning
Diouane, Youssef, Lucchi, Aurelien, Patil, Vihang
Evolutionary strategies have recently been shown to achieve competing levels of performance for complex optimization problems in reinforcement learning. In such problems, one often needs to optimize an objective function subject to a set of constraints, including for instance constraints on the entropy of a policy or to restrict the possible set of actions or states accessible to an agent. Convergence guarantees for evolutionary strategies to optimize stochastic constrained problems are however lacking in the literature. In this work, we address this problem by designing a novel optimization algorithm with a sufficient decrease mechanism that ensures convergence and that is based only on estimates of the functions. We demonstrate the applicability of this algorithm on two types of experiments: i) a control task for maximizing rewards and ii) maximizing rewards subject to a non-relaxable set of constraints.
Natural Language Processing
Originally published on Towards AI the World's Leading AI and Technology News and Media Company. If you are building an AI-related product or service, we invite you to consider becoming an AI sponsor. At Towards AI, we help scale AI and technology startups. Let us help you unleash your technology to the masses. The recommendation systems (RS) are becoming an integral part of our daily lives. This means that we can obtain what we desire either through internet-accessible applications or on social media channels. Traditional views of the recommendation problem refer to it as a simple classification or prediction problem; however, recently new evidence indicates that it is essentially a sequential problem[1]. It can therefore be formulated as a Markov decision process (MDP) and reinforcement learning (RL) methods can be employed to resolve it [1]. RL algorithms play a crucial role as these algorithms are very advantageous to cope with the dynamic environment and large space [4]. Deep Reinforcement Learning (DRL), have enabled RL to be applied to the recommendation problem with massive states and action spaces. RL-based and DRL-based methods in a classified manner based on the specific RL algorithm, like Q-learning, SARSA, and REINFORCE, that is used to optimize the recommendation policy[2].
Reinforcement Learning Framework for Server Placement and Workload Allocation in Multi-Access Edge Computing
Mazloomi, Anahita, Sami, Hani, Bentahar, Jamal, Otrok, Hadi, Mourad, Azzam
Cloud computing is a reliable solution to provide distributed computation power. However, real-time response is still challenging regarding the enormous amount of data generated by the IoT devices in 5G and 6G networks. Thus, multi-access edge computing (MEC), which consists of distributing the edge servers in the proximity of end-users to have low latency besides the higher processing power, is increasingly becoming a vital factor for the success of modern applications. This paper addresses the problem of minimizing both, the network delay, which is the main objective of MEC, and the number of edge servers to provide a MEC design with minimum cost. This MEC design consists of edge servers placement and base stations allocation, which makes it a joint combinatorial optimization problem (COP). Recently, reinforcement learning (RL) has shown promising results for COPs. However, modeling real-world problems using RL when the state and action spaces are large still needs investigation. We propose a novel RL framework with an efficient representation and modeling of the state space, action space and the penalty function in the design of the underlying Markov Decision Process (MDP) for solving our problem.
How to train an AI to play any game
This is a short guide on how to train an AI to play an arbitrary videogame using reinforcement learning. It shows step-by-step how to set up your custom game environment and train the AI utilizing the Stable-Baselines3 library. I wanted to make this guide accessible, so the presented code is not fully optimized. You can find the source on my GitHub. Unlike its supervised and unsupervised counterparts, Reinforcement Learning (RL) is not about our algorithm learning some underlying truth from a static dataset, instead it interacts with its environment to maximize a reward function (quite similar to how animals are trained in real life with treats).
Selective Credit Assignment
Chelu, Veronica, Borsa, Diana, Precup, Doina, van Hasselt, Hado
Efficient credit assignment is essential for reinforcement learning algorithms in both prediction and control settings. We describe a unified view on temporal-difference algorithms for selective credit assignment. These selective algorithms apply weightings to quantify the contribution of learning updates. We present insights into applying weightings to value-based learning and planning algorithms, and describe their role in mediating the backward credit distribution in prediction and control. Within this space, we identify some existing online learning algorithms that can assign credit selectively as special cases, as well as add new algorithms that assign credit backward in time counterfactually, allowing credit to be assigned off-trajectory and off-policy.
How to Accelerate Deep Reinforcement Learning Training
From the depths of the oceans to the blackest outposts of space, robots go where we can't. They do the work that's too dangerous or impossible for people, including maintaining infrastructure in hard-to-reach places. In factories, robots help to increase quality and safety on the assembly line. Robots, especially industrial robotic arms, are great candidates for deep reinforcement learning. Deep reinforcement learning (DRL) uses experimentation to train a deep learning solution.