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The continuous urbanisation and increase in vehicle ownership have increasingly exacerbated traffic congestion problems. In this paper, we advocate the use of epidemic theory to model the spreading of traffic congestion in urban cities. Specifically, we use the Susceptible-Infected-Recovered (SIR) model but propose to explicitly consider the road network structure in the model to understand the contagion process of road congestion. This departs from the classical SIR model where homogeneous mixing based on the law of mass action is assumed. For this purpose, we adopt the N-intertwined modeling framework for the SIR model based on continuous-time Markov chain analysis. In our evaluation, we used two real-world traffic datasets collected in California and Los Angeles. We compare our results against both classical and average-degree-based SIR models. Our results show better agreement between the model and actual congestion conditions and shed light on how congestion propagates across a road network. We see the potential application of insights gained from this work on the development of traffic congestion mitigation strategies.

This paper addresses the crucial challenge of maintaining the directed graph topology in multi-robot systems, particularly when operating under limited field-of-view constraints and with a lack of communication among robots. Traditional methods for multi-robot coordination rely heavily on inter-robot communication, which may not always be feasible, particularly in constrained or hostile environments. Our work presents a novel distributed control algorithm that leverages Control Barrier Functions (CBFs) to maintain the graph topology of a multi-robot system based solely on local, onboard sensor data. This approach is particularly beneficial in situations where external communication channels are disrupted or unavailable. The key contributions of this research are threefold: First, we design a novel control algorithm that efficiently maintains the graph topology in multi-robot systems using CBFs, which operate on neighbor detection data. Second, we perform an experimental evaluation of the algorithm, demonstrating its efficacy in controlling the flight of a team of drones using only local robot data. Third, we apply our methodology to a distributed coverage control scenario, showing that our approach can effectively manage a multi-robot system using only local information.

The Internet of Things (IoT) is a paradigm that has been widely deployed in various areas, connecting commonly used devices, from home to industry and health, among others. IoT devices generally have a small amount of memory, low processing resources, and it is often required that they have low energy consumption. Therefore, one objective of this research is to try to take advantage of a classic cable communications standard, RS485, so as to allow the connection of simple devices to the TCP/IP network through an intermediary node. Thus, the IoT device would only require an asynchronous serial port and an interface to the electrical network. To that end, data transmission tests have been carried out over interfaces based on the THVD8000 integrated circuit. The achieved results encourage to continue working on this issue. [ABSTRACT FROM AUTHOR]

The semiconductor industry has seen significant technological advancements, leading to an increase in the number of processing cores in a system-on-chip (SoC). To facilitate communication among the numerous on-chip cores, a network-on-chip (NoC) is employed. One of the main challenges of designing NoCs is power management since the NoC consumes a significant portion of the total power of the SoC. Among the power-intensive components of the NoC, routers stand out. We observe that some power-intensive components of routers, responsible for implementing turn in the mesh topology, are underutilized compared to others. Therefore, we propose Tulip, a turn-free low-power network-in-chip, that avoids within-router turns by removing the corresponding components from the router structure. On a turn (e.g., at the end of the current dimension), Tulip forces the packet to be ejected and then reinjects it to the next dimension channel (i.e., the beginning of the path along the next dimension). Due to its deadlock-free nature, Tulip's scheme may be used orthogonally with any deterministic, partially-adaptive, and fully-adaptive routing algorithms, and can easily be extended for any n-dimensional mesh topology. Our analysis reveals that Tulip can reduce the static power and area by 24%−50% and 25%-55%, respectively, for 2D-5D mesh routers. [ABSTRACT FROM AUTHOR]