Fine-Grained Prediction and Control of Covid-19 Pandemic in a City: Application to Post-Initial Stages

Predicting the evolution of the Covid-19 pandemic during its early phases was relatively easy as its dynamics were governed by few influencing factors that included a single dominant virus variant and the demographic characteristics of a given area. Several models based on a wide variety of techniques were developed for this purpose. Their prediction accuracy started deteriorating as the number of influencing factors and their interrelationships grew over time. With the pandemic evolving in a highly heterogeneous way across individual countries, states, and even individual cities, there emerged a need for a contextual and fine-grained understanding of the pandemic to come up with effective means of pandemic control. This paper presents a fine-grained model for predicting and controlling Covid-19 in a large city. Our approach borrows ideas from complex adaptive system-of-systems paradigm and adopts a concept of agent as the core modeling ion. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Adaptive Droplet Routing for MEDA Biochips via Deep Reinforcement Learning

Digital microfluidic biochips (DMFBs) based on a micro-electrode-dot-array (MEDA) architecture provide fine-grained control and sensing of droplets in real-time. However, excessive actuation of microelectrodes in MEDA biochips can lead to charge trapping during bioassay execution, causing the failure of microelectrodes and erroneous bioassay outcomes. A recently proposed enhancement to MEDA allows run-time measurement of microelectrode health information, thereby enabling synthesis of adaptive routing strategies for droplets. However, existing synthesis solutions are computationally infeasible for large MEDA biochips that have been commercialized. In this paper, we propose a synthesis framework for adaptive droplet routing in MEDA biochips via deep reinforcement learning (DRL). The framework utilizes the real-time microelectrode health feedback to synthesize droplet routes that proactively minimize the likelihood of charge trapping. We show how the adaptive routing strategies can be synthesized using DRL. We implement the DRL agent, the MEDA simulation environment, and the bioassay scheduler using the OpenAI Gym environment. Our framework obtains adaptive routing policies efficiently for COVID-19 testing protocols on large arrays that reflect the sizes of commercial MEDA biochips available in the marketplace, significantly increasing probabilities of successful bioassay completion compared to existing methods. © 2022 EDAA.