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Stochastic Rounding: Algorithms and Hardware Accelerator
No full textAlgorithms and a hardware accelerator for performing stochastic rounding (SR) are presented. The main goal is to augment the ARM M4F based multi-core processor SpiNNaker2 with a more flexible rounding functionality than is available in the ARM processor itself. The motivation of adding such functionality in hardware is based on our previous results showing improvements in numerical accuracy of ODE solvers in fixed-point arithmetic with SR, compared to standard round to nearest or bit truncation rounding modes. Performing SR purely in software can be expensive due to requirement of multiple masking and shifting instructions, and an addition operation per each rounding. Also, saturation of values is included since it usually follows rounding, which is common in fixed-point arithmetic due to a narrow dynamic range. The main intended use of the accelerator is to round fixed-point multiplier outputs, which are returned unrounded by the ARM processor in a wider fixed-point format than the arguments. The proposed accelerator is not specific to SpiNNaker, and is a generally applicable rounding unit provided a pseudo-random number generator is available that can supply random bits to it. Additionally, to the best of our knowledge, this is the first exploration of a rounding accelerator with a programmable bit position and multiple data type support
Diagrammatic Summaries for Neural Architectures
No full textThis paper advocates for diagrammatic summary publications for machine learning system architecture papers. We review existing diagram-centric scholarly practices, and summarise relevant studies on neural network system architecture diagrams. We subsequently propose three opportunities: Diagram guidelines, diagrammatic system summary publications, and the community creation of a formal diagram standards, which could be integrated with existing LaTeX + PDF publication processes
FuSeBMC: An Energy-Efficient Test Generator for Finding Security Vulnerabilities in C Programs
No full textWe describe and evaluate a novel approach FuSeBMC that exploits fuzzing and BMC engines to detect security vulnerability in C programs. It explores and analyzes the target C program by injecting labels that guide those engines to produce test-cases. FuSeBMC also exploits selective fuzzer to produce test-cases for the labels that fuzzing and BMC engines could not produce test-cases. Lastly, we manage each engine's execution time to improve FuSeBMC's energy consumption. As a result, FuSeBMC guides the fuzzing and BMC engines to explore more profound in the target C programs and then produce test-cases that achieve higher coverage with lower energy consumption to detect bugs efficiently. We evaluated FuSeBMC by participating in Test-Comp 2021 to test the ability of the tool in two categories of the competition, which are code coverage and bug detection. The competition results show that FuSeBMC performs well if compared to the state-of-the-art software testing tools. FuSeBMC achieved 3 awards in the Test-Comp 2021: first place in the Cover-Error category, second place in the Overall category, and third place in the Low Energy Consumption
Post-pandemic Patient Safety Culture: A Case from a large Metropolitan Hospital Group in Taiwan
No full textPatient safety is the core goal of medical institutions. The present study focuses on the patient safety culture and staff well-being admit the COVID-19 pandemic. 337 employees in a large metropolitan hospital group who had participated in the quality improvement interventions completed an anonymous questionnaire of patient safety culture and personal well-being. The multiple regression analyses indicated that managerial role, seniority, female gender and direct contact with patient were significantly related to the positive attitude on overall or certain di-mensions of safety culture. Multivariate analysis also found that dimensions of teamwork cli-mate, safety climate, job satisfaction, and stress recognition as patient safety culture predicted staff exhaustion. Finally, comparing with the available institutional historic data in 2018, the COVID group scored higher on the working condition dimension of patient safety culture, but lower on the stress recognition dimension. The COVID group also scored higher on exhaustion. In the post-pandemic era, there seems to be an improvement on certain aspect of the patient safety culture among hospital staff, and the improvement is more prevalent for managers. However, exhaustion is also a poignant problem for all employees. These findings can inform hospital decision-makers in planning and implementing future improvements of patient safety culture and promoting employee well-being and resilience. Our findings also reveal directions for future research
Cut-and-project quasicrystals, lattices, and dense forests
No full textDense forests are discrete subsets of Euclidean space which are uniformly close to all sufficiently long line segments. The degree of density of a dense forest is measured by its visibility function. We show that cut-and-project quasicrystals are never dense forests, but their finite unions could be uniformly discrete dense forests. On the other hand, we show that finite unions of lattices typically are dense forests, and give a bound on their visibility function, which is close to optimal. We also construct an explicit finite union of lattices which is a uniformly discrete dense forest with an explicit bound on its visibility
Reconstruction of the Spanish money supply, 1492-1810
No full textHow did the Spanish money supply evolve in the aftermath of the discovery of large amounts of precious metals in Spanish America? We synthesize the available data on the mining of precious metals and their international flow to estimate the money supply for Spain from 1492 to 1810. Our estimate suggests that the Spanish money supply increased more than ten-fold. Viewed through the equation of exchange this money supply increase can account for most of the price level rise in early modern Spain
<sup>23</sup>Na NMR T<sub>1</sub> relaxation measurements as a probe for diffusion and dynamics of sodium ions in salt-glycerol mixtures
No full textMixtures of sodium salts with oxygen-containing molecules are useful from the perspective of applications such as sodium ion batteries but also because they fill the gap between deep eutectic solvents and molten salt hydrates. In a previous work, the physical properties (such as diffusion coefficients, conductivity, viscosity and glass transition temperature) of four salts, namely Na2B4O7.10H2O, NaOAc.3H2O, NaBr, and NaOAc, were measured with glycerol. Pulsed-field gradient (PFG) NMR was also used to measure self-diffusion coefficients of 1H-bearing species. However, the technique was not able to measure diffusion of sodium ions due to the very fast NMR relaxation rate of such species, resulting in loss of PFG NMR signal. In the current work, this study is expanded to using 23Na T1 relaxation measurements, which under certain assumptions, can be translated into diffusion coefficients. Analysis of the physical properties is then correlated with self-diffusion coefficient measurements to elucidate information about structure and ionic mobility. It is shown that NaOAc.3H2O, NaBr and NaOAc fit models for ionic conductivity and diffusion, which are consistent with ionic liquids where charge transport is limited by ionic mobility rather than the number of charge carriers. The waters of hydration of NaOAc.3H2O do not appear to form a separate phase but instead are strongly coordinated to the cation. In contrast, Na2B4O7.10H2O appears to form a water-rich phase with enhanced sodium mobility
Global guideline for the diagnosis and management of rare yeast infections: An initiative of the ECMM in cooperation with ISHAM and ASM
No full textUncommon, or rare, yeast infections are on the rise given increasing numbers of immunocompromised and seriously-ill patients. The major pathogens include those of the genera Geotrichum, Saprochaete/Magnusiomyces and Trichosporon species as well as Kodamaea, Malassezia, Pseudozyma (Moesziomyces/Dirkmeia), Rhodotorula, Saccharomyces and Sporobolomyces species. A considered approach to the complex, multidisciplinary management of infections caused by these pathogens is essential to optimising patient outcomes; however current management guidelines are either region-specific or require updating. In alignment with the “One World–One Guideline” initiative to incorporate regional differences, experts from diverse geographic regions analysed the published literature describing the epidemiology and management of the above rare yeasts. This guideline summarizes the consensus recommendations with regards to the diagnostic and therapeutic options for these rare yeast infections with the intent of providing practical assistance in in clinical decision making. Because there is less clinical experience of rare yeast infections and studies on these were not randomized nor were groups compared, most recommendations are not robust in their validation but represent insights using expert opinions and in-vitro susceptibility results. We report in the present manuscript the key features of the epidemiology, diagnosis, antifungal susceptibility and treatment outcomes of Geotrichum, Saprochaete/Magnusiomyces and Trichosporon infections
Conditions and dynamics of magma storage in the Snæfellsnes volcanic zone, Western Iceland: insights from the Búðahraun and Berserkjahraun eruptions
No full textEstablishing the conditions and dynamics of pre-eruptive magma storage and transfer within transient transcrustal storage networks is a major focus of quantitative volcanic petrology. In Iceland, the behaviour, conditions and timescales of magmatic processes within on-rift plumbing systems are increasingly well constrained. However, relatively little is known about magma storage and transfer in off-rift zones, despite off-rift volcanoes being able to generate hazardous explosive eruptions after centuries or millennia of dormancy (e.g. 2010 AD Eyjafjallajökull; 1362 AD Öræfajökull; 3.0 ka, 4.2 ka and 1104 AD Hekla). We present a combined geochemical and geothermobarometric study of magma storage and transfer recorded in the products of the postglacial Búðahraun (~5.0-8.0 ka) and Berserkjahraun (~4.0 ka) eruptions within the Snæfellsnes volcanic zone. The eruption products contain diverse and compositionally heterogeneous macrocryst cargoes recording complex petrogenetic histories of crystal evolution and inheritance from different parts of the sub-volcanic plumbing systems. Geothermobarometry indicates two compositionally and thermally heterogeneous magma storage regions located in the lower (20±4 km) and upper-mid (11±3 km) crust. Crystallisation pressure and depth estimates coincide with comparable data from Vatnafell, a small sub-glacial table mountain (tuya) in the centre of the Snæfellsnes volcanic zone, indicating that the nature and conditions of magma storage have remained unchanged since the Upper Pleistocene. Trace element zoning of clinopyroxene macrocrysts indicates that mafic recharge into the upper-mid-crustal storage zone triggered the eruptions of Búðahraun and Berserkjahraun. Evidence for eruption-triggering mafic recharge and basaltic cannibalism involving the transfer and amalgamation of crystals with different evolutionary histories sets the Búðahraun and Berserkjahraun eruptions apart from other studied eruptions in Iceland. We propose that the compositional and textural diversity preserved within the crystal cargoes are a direct consequence of the reduced heat flow beneath the Snæfellsnes volcanic zone, which favours the formation of isolated melt pockets in which compositionally diverse macrocryst populations formed. Periodic flushes of primitive basaltic magma from depth promote widespread mixing with evolved melts, resulting in the assembly of crystals with diverse ancestries from different parts of the sub-volcanic systems. Insights gained from the diverse macrocryst cargoes of Búðahraun and Berserkjahraun and comparisons with recent off-rift volcanism in Iceland are essential for the development of future monitoring efforts and hazard evaluation. Although volcanism within the Snæfellsnes volcanic zone differs fundamentally from that in rift zones where eruptions are controlled by extensional spreading, magma ascent from depth still appears to follow pre-existing tectonic escape routes. This could result in extremely short advance warning times on the order of a few days
Fostering Energy Transition in Smart Cities: DLTs for Peer-to-Peer Electricity Trading
No full textThis paper explores the applications of Distributed Ledger Technologies (DLTs) in Peer-to-Peer (P2P) electricity trading. It highlights the challenges and trade-offs of applying three different DLTs: Blockchain, Directed Acyclic Graph (DAG), and Holochain. First, the study introduces the energy transition concept in the smart city context. Second, P2P electricity trading and its supporting trading mechanisms are introduced. Third, DLTs are defined and three different types of DLTs are introduced. Forth, possibilities, challenges, and consequences of applying DLTs in electricity trading are explained. Last, applying DLTs for P2P electricity trading from different aspects are discussed. This paper provides a benchmark for applying DLTs to foster energy transition in smart cities. It highlights how this type of technology can serve smart circular economy