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The combustion of conventional Jet A, alongside two alternative jet fuels, C1 and C5, is simulated with Large Eddy Simulations (LES) in a generic single-cup spray combustor during idle and cruise conditions. The spray is modeled using Lagrangian particle tracking and the combustion chemistry of each fuel is modeled by skeletal reaction mechanisms. The volatility and atomizability of each fuel dire

Human–robot collaboration (HRC) in manufacturing environments requires that physical safety can be guaranteed. Control methods that implicitly regulate the interaction forces between a controlled robot and its environment, such as impedance control, are often used for safety in HRC. However, these methods could be complemented by restricting the robot operational space for additional safety guaran

In this paper, an iterative learning strategy was developed to improve trajectory tracking for an impedance-controlled robot manipulator. In this learning strategy, an update law was proposed to modify the Cartesian reference of an impedance controller. Also, the conditions that ensure its convergence considering the dynamics of the robot were derived. Finally, an experimental evaluation was perfo

Planning and navigation in real-time traffic is challenging, since the driving environment (e.g., road network and infrastructure) is complex and the accurate prediction of surrounding vehicles is hard. To address this, this paper proposes an environment and uncertainty-aware robust motion-planning strategy. The method achieves environment awareness by considering road-geometry constraints in the

Safe motion planning for robotic systems in dynamic environments is nontrivial in the presence of uncertain obstacles, where estimation of obstacle uncertainties is crucial in predicting future motions of dynamic obstacles. The worst case characterization gives a conservative uncertainty prediction and may result in infeasible motion planning for the ego robotic system. In this article, an efficie

Lean, premixed, swirl-stabilized flames are widely used in modern Dry Low Emissions gas turbine combustors; however, the turbulent combustion process under those conditions is known to be extremely sensitive and prone to instabilities. Numerical simulations can be a valuable tool in predicting the effects of alternative fuels; however, the sensitivity of the results to different models ought to be

Context Developing compilers and static analysis tools (“language tools”) is a difficult and time-consuming task. We have previously presented property probes, a technique to help the language tool developer build understanding of their tool. A probe presents a live view into the internals of the compiler, enabling the developer to see all the intermediate steps of a compilation or analysis rather

Background: Swimming ability among children in the city of Malmö, Sweden is strongly affected by socioeconomic differences. We investigated to what extent mediating health and lifestyle factors, such as children’s eating, sleeping and physical activity habits, as well as the characteristics of the social and working environment at both school and home, could explain the socioeconomic gradient in s

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are persistent substances with surfactant and repellent properties. Municipal drinking water contaminated with PFAS had been distributed for decades to one third of households in Ronneby, Sweden. The source was firefighting foam used in a nearby airfield since the mid-1980s. Clean water was provided from December 16, 2013.AIMS: The purpose was

Background: Impaired quadriceps muscle strength after anterior cruciate ligament reconstruction (ACLR) is associated with worse clinical outcomes and a risk of reinjuries. Yet, we know little about quadriceps muscle strength in patients reconstructed with a quadriceps tendon (QT) graft, which is increasing in popularity worldwide. Purpose: To describe and compare isokinetic quadriceps strength in

The PID controller is the by far most frequently employed type of controller. As you read, billions of digitally implemented PID controllers are running, shaping the dynamic behavior of anything from the fan speed in your laptop to safety-critical components in nuclear power plants. Given the abundance of commissioned PID controllers, it is surprisingly hard to find a single source that provides a

This paper introduces an improved method for real-time brain computer interface control. We demonstrate how Bayesian optimization and feedback can be used to achieve faster statistical convergence by controlling the sequence of stimuli shown in a brain computer interface based on a visual oddball paradigm.

With increased autonomy in marine vessels, autonomous surface vessels (ASVs) and conventionally manned vessels need to coexist at sea. Any relocation needs to include collision avoidance according to the traffic rules at sea, COLREGs. Here, a local collision-avoidance planner for an archipelago environment is presented. The optimization-based local planner presented considers a predefined nominal

Amid growing concerns about hardware security, comprehensive security testing has become essential for chip certification. This paper proposes a deep-testing method for identifying Trojans of particular concern to middle-to-high-end users, with a focus on illegal instructions. A hidden instruction Trojan can employ a low-probability sequence of normal instructions as a boot sequence, which is foll

Optimization of vehicle maneuvers using dynamic models in constrained spaces is challenging. Homotopic optimization, which has shown success for vehicle maneuvers with kinematic models, is studied in the case where the vehicle model is governed by dynamic equations considering road-tire interactions. This method involves a sequence of optimization problems that start with a large free space. By it

The potential of additional steering possibilities (like rear-wheel or all-wheel steering) is analyzed for critical situations to investigate possible safety improvements. For this purpose, a dynamic optimization problem is formulated to find the best possible maneuver. The optimization criterion is to maximize the entry speed into a constant radius 90°-curve. The optimization problem is solved fo

This paper addresses the path-tracking problem of time-optimal trajectories under model uncertainties, by proposing a real-time predictive scaling algorithm. The algorithm is formulated as a convex optimization problem, designed to balance the trade-off between improving feasibility and time optimality of a trajectory. The predicted trajectory is scaled based on the presence of path segments that

In this issue, “25 Years Ago” revisits the article “Out of Control Because of Harmonics: An Analysis of the Harmonic Response of an Inverter Locomotive,” by Erik Möllerstedt and Bo Bernhardsson, in IEEE Control Systems Magazine, vol. 20, no. 4, pp. 70–81. Below is an excerpt from the article.

This study investigates how changes in temperature affect the secondary organic aerosol (SOA) phase state. SOA was formed by α-pinene ozonolysis in an atmospheric simulation chamber at temperatures (T0) in the range of 257–283 K at RH0< 20%. After more than 14 h of SOA aging, one or more heating and cooling ramps were performed. Upon heating, we observe that the onset of evaporative SOA shrinkage

Open and shared government data and services offer an instrument for achieving innovation, interoperability, and transparency in public services but require relevant competency, resources, and culture to realise, something that the public sector actors often lack. In this case study, we exemplify how these challenges to data sharing may be tackled through horizontal coordination in the case of Tra