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ConCeal: A Winograd Convolution Code Template for Optimising GCU in Parallel
No full textBy minimising arithmetic operations, Winograd convolution substantially reduces the computational complexity of convolution, a pivotal operation in the training and inference stages of Convolutional Neural Networks (CNNs). This study leverages the hardware architecture and capabilities of Shanghai Enflame Technology's AI accelerator, the General Computing Unit (GCU). We develop a code template named ConCeal for Winograd convolution with 3 × 3 kernels, employing a set of interrelated optimisations, including task partitioning, memory layout design, and parallelism. These optimisations fully exploit GCU's computing resources by optimising dataflow and parallelizing the execution of tasks on GCU cores, thereby enhancing Winograd convolution. Moreover, the integrated optimisations in the template are efficiently applicable to other operators, such as max pooling. Using this template, we implement and assess the performance of four Winograd convolution operators on GCU. The experimental results showcase that Conceal operators achieve a maximum of 2.04× and an average of 1.49× speedup compared to the fastest GEMM-based convolution implementations on GCU. Additionally, the ConCeal operators demonstrate competitive or superior computing resource utilisation in certain ResNet and VGG convolution layers when compared to cuDNN on RTX2080
Philosophy across borders:perspectives from contemporary theory, edited by Emma Ingala and Gavin Rae, New York, London, Routledge, 2025, 266 pp., ISBN 9781032462912
No full textThermal performance and flow characterization of oscillating heat pipe under ultrasonic field
No full textOscillating Heat Pipes (OHPs) are passive, wickless two-phase thermal devices which can be integrated into Ultrasonic Machining Systems (UMS) to stabilize operating temperatures, prevent performance degradation due to excessive heat, and improve both system stability and machining outcomes. Ultrasonic vibrations influence the heat transfer characteristics of OHPs, but the effects are not yet fully understood. This paper experimentally examines how an ultrasonic field affects the thermal performance of OHPs, focusing on temperature distribution and flow pattern changes to understand the heat transfer mechanisms. The study shows that the ultrasonic field can enhance the heat transfer coefficient of OHPs by almost 20%. This enhancement decreases as the operating temperature rises, with the greatest improvement at 70 °C. Further analysis reveals that ultrasonic field promotes a periodic steady-state operation inside the OHPs and characteristic periodic temperature signals. Additionally, ultrasonic cavitation enhances bubble formation and the phase change heat transfer within the OHPs, facilitating the development of flow pattern and promoting unidirectional circulation, both of which improve heat transfer. By integrating OHPs into UMS, operating temperatures can be better stabilized, leading to enhanced vibration stability in the UMS and improved surface quality of the workpiece
3D asymmetric loop thermosyphon under radial rotation:A novel method for enhanced heat transfer in grinding
No full textSymmetrical radial-rotating thermosyphons (SLTs) have been investigated as a means to enhance heat transfer during grinding, thereby preventing workpiece burns and improving overall process efficiency. These LTs feature channels with a uniform diameter, yet previous research has shown significant limitations under conditions of high centrifugal acceleration, which negatively impacts their heat transfer capability. Specifically, SLTs with uniform diameter channels experience flow stratification due to high centrifugal forces, causing a reduction in oscillatory motion and leading to reduced heat transfer efficiency. To address such limitations, a novel 3D asymmetric loop thermosyphon (ALT) with two different channel diameters is proposed. This asymmetric configuration induces an additional pressure difference, which appears to counteract the adverse effects of centrifugal forces, thereby sustaining oscillatory motion and enhancing heat transfer especially at higher rotational speeds. The thermal performance of the ALT is evaluated in terms of thermal resistance, temperature uniformity, and heat dissipation efficiency under a wide range of centrifugal accelerations and heat fluxes. Compared to SLT, at accelerations of 18g, 73.5g, and 165g, the novel ALT demonstrates a reduction in thermal resistance of 31 %, 43 %, and 44 %, respectively. The temperature uniformity is also improved compared to SLT by 37 %. Results also showed that the ALT works as an Oscillating Heat Pipe when the acceleration remains under 1.12g. These results indicate that the ALT effectively improves heat transfer performance by maintaining oscillatory motion and enhancing temperature uniformity, ultimately offering superior adaptability for high-speed grinding applications, ensuring more stable thermal management, reducing workpiece burns, and minimizing grinding wheel wear
Grassroots activism in wetland spaces; Ecological stewardship, regenerative praxis, creative imaginations
No full textWetlands epitomise 21st-century natures in transition. Subject to global ‘drain and reclaim’ strategies across the 20th century in support of agro-industrialisation processes accelerated by global wars and enabled through neo- classical economic discourses, around 60% of wetlands have been lost worldwide. Ther central importance as amorphous landforms, which store and sequester blue-green carbon, enable a wide variety of biodiversity, recycle nutrients, and purify air and water systems, are now recognised as intrinsic to regenerative strategies in response to climate breakdown. Despite this their entanglement in a range of extractative global processes continues unabated. Processes as diverse as lithium mining in the Atacama Desert, the exploitation of new oil and gas reserves in the Congo River basin and Caspian Sea, genocidal land-grabbing in the Iraqi marshes to speculative property financing in Jakarta, Bangkok, and New York have direct and irrefutable impacts on these diverse ecosystems right into the present. This chapter explores the varied and diverse activism responses by a wide range of global individuals, groups, and movements which seek to amplify and challenge the processes and power dynamics which are impacting upon and reshaping these wetland spaces. This illuminates the range of actions and intentions utilised by grassroots wetlands activists to usurp power – through direct action, regenerative praxis, quiet engagement, and inculcating other worldings through imaginative redirection and speculative animations
Is this the promised end? Low end theory, education and the illusion of survival
No full textWe inhabit end-times in which talk about the collapse of civilisation, history or humanity is everywhere, but we have been here before. This chapter builds on our previous analysis of the effects of the pandemic to explore further the ways in which current attempts to manipulate history and the rhetoric of apocalypse and survival offer an imperative for change. In order to assess our chances of survival, we reassess two previous “end-times” of revolution and upheaval: 1968 and 1989 and their effects on education in order to try to determine what we can learn from these events, particularly as actors in the field of education. The theoretical foundation for the analysis draws on the work of Benjamin, Baudrillard, Fisher, Nuttall and Jasen. Our concluding thoughts emphasise that education has an important role to play in understanding and unforgetting how what got to this position and how we can reconstitute and reactivate misplaced possibilities to try to ensure that survival is not an illusion
East Asian Design History Reader:Modernities and Formation of the Inter-East Asian Design, 1900-1945
No full textAssessing k-ε Family Turbulence Models for a Study of Sonic Jet Flow in a Quiescent Environment
No full textThis study evaluates the performance of k-ε turbulence models in simulating under-expanded sonic jet flows in a quiescent medium, with a particular focus on shock cell structures, turbulence intensity, and velocity profiles. Numerical simulations were conducted using explicit and implicit solvers with and without compressibility corrections, and the results were validated against data from the literature. The inclusion of compressibility corrections significantly improved the accuracy of the predicted shock cell structures, especially in the far field, where the oscillatory nature of the velocity and turbulence profiles was captured effectively. The analysis revealed that higher inlet turbulence intensity (10%) enhanced near-field mixing and momentum dissipation, while turbulence intensity converged in the far field regardless of initial conditions
Comparison of high-speed videography and phase Doppler anemometry applied to flat-fan sprays
No full textThis aim of this study is to investigate local droplet size and velocity distributions in a near two-dimensional quasi-steady flat-fan water spray injected under quiescent conditions. The objective is to provide accurate experimental data to validate the generalised Fully Lagrangian Approach (gFLA) model for polydisperse droplet flows. To achieve this, droplet size and velocity distributions were characterised using classical phase Doppler anemometry (PDA) and a recently-developed imaging framework based on high-speed shadowgraphy in conjunction with particle image velocimetry (PIV). The latter technique can also be referred to as high speed videography (HSV). Average horizontal velocity components obtained from both techniques are in good agreement within the main body of the spray. However, average vertical velocity components measured using HSV were consistently lower than those from PDA by up to 20%. This discrepancy is primarily attributed to the broader dynamic range of PDA, allowing it to capture a wider spectrum of velocities, whereas HSV is constrained by the temporal and spatial resolution of the optical setup. Both techniques showed that droplet number median diameter decreases downstream, due to secondary and tertiary atomisation, though PDA consistently reported larger values compared to HSV by up to 15%. These differences stem from the limited size range of each method, as HSV measures droplet diameters from 10–300 µm, while PDA is restricted to 2–120 µm. These findings highlight the importance of selecting an appropriate combination of measurement techniques for spray characterisation. PDA is well-suited for velocity measurements due to its high temporal resolution, while a hybrid approach incorporating both PDA and HSV for droplet size distributions offers a more comprehensive representation of the spray field