Network enabled partial reconfiguration for distributed FPGA edge acceleration

Partial reconfiguration supports virtualisation of applications on FPGAs, enabling compute to dynamically adapt to workloads in distributed infrastructure and datecenters. While the latter often makes use of the PCIe interface and supporting infrastructure to allocate and load compute kernels via a host CPU, FPGAs are becoming increasingly popular as standalone resources in edge-computing, requiring them to manage ac- celerators autonomously. This paper presents a platform that supports the managing of accelerator bitstreams over the network interface on a Xilinx Zynq device without intervention by the Arm processor. We compare against traditional vendor provided PR management for both library accelerators and custom acceler- ators and show that we achieve a 29% decrease in reconfiguration trigger latency using this approach

An interval Kalman filter-based fuzzy multi-sensor fusion approach for fault-tolerant heading estimation of an autonomous surface vehicle

This article presents a novel fuzzy–logic based multi-sensor data fusion algorithm for combining heading estimates from three separate weighted interval Kalman filters to construct a robust, fault-tolerant heading estimator for the navigation of the Springer autonomous surface vehicle. A single, low-cost gyroscopic unit and three independent compasses are used to acquire data onboard the vehicle. The gyroscope data, prone to sporadic bias drifts, are fused individually with readings from each of the compasses via a weighted interval Kalman filter. Unlike the standard Kalman filter, the weighted interval Kalman filter is able to provide a robust heading estimate even when subject to such gyroscope bias drifts. The three ensuing weighted interval Kalman filter estimates of the vehicle’s heading are then fused via a fuzzy logic algorithm designed to provide an accurate heading estimate even when two of the three compasses develop a fault at any time. Simulations and real-time trials demonstrate the effectiveness of the proposed method. </jats:p

Demographic, health, physical activity, and workplace factors are associated with lower healthy working life expectancy and life expectancy at age 50

\ua9 The Author(s) 2024.Although retirement ages are rising in the United Kingdom and other countries, the average number of years people in England can expect to spend both healthy and work from age 50 (Healthy Working Life Expectancy; HWLE) is less than the number of years to the State Pension age. This study aimed to estimate HWLE with the presence and absence of selected health, socio-demographic, physical activity, and workplace factors relevant to stakeholders focusing on improving work participation. Data from 11,540 adults in the English Longitudinal Study of Ageing were analysed using a continuous time 3-state multi-state model. Age-adjusted hazard rate ratios (aHRR) were estimated for transitions between health and work states associated with individual and combinations of health, socio-demographic, and workplace factors. HWLE from age 50 was 3.3 years fewer on average for people with pain interference (6.54 years with 95% confidence interval [6.07, 7.01]) compared to those without (9.79 [9.50, 10.08]). Osteoarthritis and mental health problems were associated with 2.2 and 2.9 fewer healthy working years respectively (HWLE for people without osteoarthritis: 9.50 years [9.22, 9.79]; HWLE with osteoarthritis: 7.29 years [6.20, 8.39]; HWLE without mental health problems: 9.76 years [9.48, 10.05]; HWLE with mental health problems: 6.87 years [1.58, 12.15]). Obesity and physical inactivity were associated with 0.9 and 2.0 fewer healthy working years respectively (HWLE without obesity: 9.31 years [9.01, 9.62]; HWLE with obesity: 8.44 years [8.02, 8.86]; HWLE without physical inactivity: 9.62 years [9.32, 9.91]; HWLE with physical inactivity: 7.67 years [7.23, 8.12]). Workers without autonomy at work or with inadequate support at work were expected to lose 1.8 and 1.7 years respectively in work with good health from age 50 (HWLE for workers with autonomy: 9.50 years [9.20, 9.79]; HWLE for workers lacking autonomy: 7.67 years [7.22, 8.12]; HWLE for workers with support: 9.52 years [9.22, 9.82]; HWLE for workers with inadequate support: 7.86 years [7.22, 8.12]). This study identified demographic, health, physical activity, and workplace factors associated with lower HWLE and life expectancy at age 50. Identifying the extent of the impact on healthy working life highlights these factors as targets and the potential to mitigate against premature work exit is encouraging to policy-makers seeking to extend working life as well as people with musculoskeletal and mental health conditions and their employers. The HWLE gaps suggest that interventions are needed to promote the health, wellbeing and work outcomes of subpopulations with long-term health conditions

Modelling the costs and benefits of hybrid buses from a whole-life perspective

Hybrid electric-diesel engine technologies offer the potential to reduce fuel consumption in buses by around 40%. These savings can largely be attributed to regenerative braking – the ability to store in a battery energy that would otherwise have been lost under braking. Lower fuel consumption makes sense economically for bus operators through reduced running costs; hybrid engines have other wider benefits, though, such as reducing emissions and noise, and providing smoother acceleration and braking. The costs associated with hybrid technologies are significant, however, with hybrid vehicles currently costing around 50% more to buy than conventional buses. With Alexander Dennis and BAE Systems, UCL is conducting a three-year systems engineering research and development project to adapt and optimise hybrid buses for the UK and European market. This paper investigates one aspect of this project – the costs and benefits of introducing hybrid bus technologies from a whole-life perspective. We find that fuel and emissions savings alone do not provide a compelling case for hybrid buses based on current prices. However, as the cost of fuel rises, and when the social and environmental impacts of motor vehicle use are better accounted for, hybrid technology outperforms conventional diesel technology

Study of real-time fuel consumption model for large bulk carrier

With a 53,000-ton coastal bulk carrier as the selected ship, modelling and simulating of the ship real-time fuel consumption are carried out. Firstly, the on-board data collection system is introduced as well as the operational features of the selected ship. Then, based on the interaction relation of the hull-engine-propeller, the real-time fuel consumption model of the selected ship is developed using empirical formulas. Lastly, this model is simulated on the MATLAB/Simulink considering the impact of the random environmental factors, like, wind and wave. Comparison analysis between the simulated results and the actual measurement data is also carried out. The results indicate that the measured fuel consumption and speed shows a high degree of dispersion due to the Changeable working condition of the ship and the uncertainty existing in the on-board data monitoring system; the developed model has a good accuracy in predicting real-time fuel consumption. This research could help the ship manager to assess the likely fuel consumption level under different ocean environment

Build automation and runtime abstraction for partial reconfiguration on Xilinx Zynq UltraScale+

Partial reconfiguration (PR) is fundamental to build- ing adaptive systems on modern FPGA SoCs, where hardware can be adapted dynamically at runtime. Vendor supported reconfiguration is performance limited, drivers entail complex memory management, and software/hardware design requires detailed knowledge of the underlying hardware. This paper presents a collection of abstractions that provide high performance reconfiguration of hardware from within the Linux userspace, automating the process of building PR applications, and adding support for the Xilinx Zynq UltraScale+ architecture. We compare our abstractions against vendor tooling for PR management and open source tools supporting PR within Linux. Our tools provides automation and abstraction layers, from defining PR configurations through to compiling and packaging Linux with support for userspace PR control, targeted for non- experts

Dynamic ductile to brittle transition in a one-dimensional model of viscoplasticity

We study two closely related, nonlinear models of a viscoplastic solid. These models capture essential features of plasticity over a wide range of strain rates and applied stresses. They exhibit inelastic strain relaxation and steady flow above a well defined yield stress. In this paper, we describe a first step in exploring the implications of these models for theories of fracture and related phenomena. We consider a one dimensional problem of decohesion from a substrate of a membrane that obeys the viscoplastic constitutive equations that we have constructed. We find that, quite generally, when the yield stress becomes smaller than some threshold value, the energy required for steady decohesion becomes a non-monotonic function of the decohesion speed. As a consequence, steady state decohesion at certain speeds becomes unstable. We believe that these results are relevant to understanding the ductile to brittle transition as well as fracture stability.Comment: 10 pages, REVTeX, 12 postscript figure

Glasgow supported self-management trial (GSuST) for patients with moderate to severe COPD: randomised controlled trial

Objective To determine whether supported self management in chronic obstructive pulmonary disease (COPD) can reduce hospital readmissions in the United Kingdom

Cooling Fluids and Ambient Temperature: Sensitivity Performance of a Container Ship Organic Rankine Cycle Unit

The objective of this paper is to design organic Rankine cycle units that are cooled by air or seawater and show the changes in net power output and power requirement as the ambient air temperatures change both geographically and seasonally. The organic Rankine cycle unit uses the available waste heat from the scavenge air system for a 4,100 TEU container ship. This work uses a two-step single objective optimisation capable of selecting 14 design characteristics of the organic Rankine cycle unit and with the aim of minimising the vessel’s CO2 emissions. The work contributes to the study of off-design operation and different cooling fluids for marine waste heat recovery systems. The results show that the organic Rankine cycle unit is more adaptable to ambient air temperatures when using seawater as a cooling fluid while air is an attractive option for extremely low ambient temperatures

Evaluation of Electric-Turbo-Charging applied to Marine Diesel-Engines

Electro-Turbo-Compounding (ETC) is a system whereby energy contained in the hot gas of a diesel-engine exhaust is partially recovered through its conversion via a high-speed gas turbine driven alternator into electrical energy. ETC makes a diesel-engine system work more cleanly and effectively thereby improving power density and fuel efficiency. The technology is equally suited to new-build and retrofit applications. Applications to date have been extensive in the 150 kW – 2 MW range and the 10 MW – 20 MW but almost exclusive to shore-based power stations across the world. This paper reports on the progress of an Innovate UK funded project (2015-18) to develop ‘marinised’ units with partners UCL, Bowman Power Group Ltd., Lloyd’s Register and Rolls Royce PLC. With an expectation on the shipping industry (including naval ships) to reduce their carbon footprint the ETC is suitable for marine engineering application in those ships not easily able to use the conventional Rankine Cycle exhaust gas waste heat recovery system. The paper discussions include the design, modelling and practical testing approaches, results on performance for various arrangements for propulsion and electrical power, and importantly the integration challenge to ensure NOx Compliance and Certification. Within the paper discussion is also made about the financial aspects for propulsion and electric generation applications. The operating profile of different vessels gives different paybacks which are particularly favourable at times of rising fuel prices