A route network planning method for urban air delivery

High-tech giants and start-ups are investing in drone technologies to provide urban air delivery service, which is expected to solve the last-mile problem and mitigate road traffic congestion. However, air delivery service will not scale up without proper traffic management for drones in dense urban environment. Currently, a range of Concepts...

Barrier Function-based Safe Reinforcement Learning for Formation Control of Mobile Robots

Distributed model predictive control (DMPC) concerns how to online control multiple robotic systems with constraints effectively. However, the nonlinearity, nonconvexity, and strong interconnections of dynamic system models and constraints can make the real-time and real-world DMPC implementations nontrivial. Reinforcement learning (RL)...

Logging Practices with Mobile Analytics: An Empirical Study on Firebase

Software logs are of great value in both industrial and open-source projects. Mobile analytics logging enables developers to collect logs remotely from their apps running on end user devices at the cost of recording and transmitting logs across the Internet to a centralised infrastructure.This paper makes a first step in characterising...

Spatial-temporal potential exposure risk analytics and urban sustainability impacts related to COVID-19 mitigation: A perspective from car mobility behaviour

Coronavirus disease-2019 (COVID-19) poses a significant threat to the population and urban sustainability worldwide. The surge mitigation is complicated and associates many factors, including the pandemic status, policy, socioeconomics and resident behaviours. Modelling and analytics with spatial-temporal big urban data are required to assist...

Characterization of an Acetone Detector based on a Suspended WO3-Gate AlGaN/GaN HEMT Integrated with Micro-heater

A suspended AlGaN/GaN high electron mobility transistor (HEMT) sensor with a tungsten trioxide (WO 3 ) nanofilm modified gate was microfabricated and characterized for ppm-level acetone gas detection. The sensor featured a suspended circular membrane structure and an integrated microheater to select the optimum working temperature. High working...

Determination of the intrinsic α/γ interface mobility during massive transformations in interstitial free Fe-X alloys

Kinetics of the austenite (γ) to ferrite (α) transformation and the reverse ferrite (α) to austenite (γ) transformation in a series of Fe-X (X = Ni, Mn and Co) binary alloys has been experimentally and theoretically investigated. A transition from partitioning to partitionless transformation has been predicted to occur during both the γ→α and...

Steering Micro-Robotic Swarm by Dynamic Actuating Fields

We present a general solution for steering microrobotic<br/>swarm by dynamic actuating fields. In our approach, the<br/>motion of micro-robots is controlled by changing the actuating<br/>direction of a field applied to them. The time-series sequence<br/>of actuating field’s directions can be computed automatically.<br/>Given a target position in...

Single-grain Si thin-film transistors on flexible polyimide substrate fabricated from doctor-blade coated liquid-Si

Solution process of silicon will provide high-speed transistor fabrication with low-cost by, for example, roll-to-roll process. In this paper, a low-temperature process (350?°C) is reported for fabrication of high-quality Si devices on a polyimide substrate from doctor-blade coated liquid-Si. With this method, different semiconductor devices...

X-ray investigation of buried SiGe islands for devices with strain-enhanced mobility

In this work self-organized SiGe islands are used as stressors for Si capping layers, which later act as carrier channels in field effect transistors. To be able to address individual islands and to obtain a sufficiently narrow distribution of their properties, the SiGe islands are grown by molecular beam epitaxy on prepatterned Si substrates,...