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Energy-aware AI-driven Framework for Edge Computing-based IoT Applications
Get PDFThe significant growth in the number of Internetof- things (IoT) devices has given impetus to the idea of edge computing for several applications. In addition, energy harvestable or wireless-powered wearable devices are envisioned to empower the edge intelligence in IoT applications. However, the intermittent energy supply and network connectivity of such devices in scenarios including remote areas and hard-to-reach regions such as in-body applications can limit the performance of edge computing-based IoT applications. Hence, deploying stateof-the-art convolutional neural networks (CNNs) on such energy constrained devices is not feasible due to their computational cost. Existing model compression methods such as network pruning and quantization can reduce complexity, but these methods only work for fixed computational or energy requirements, which is not the case for edge devices with an intermittent energy source. In this work, we propose a pruning scheme based on deep reinforcement learning (DRL), which can compress the CNN model adaptively according to the energy dictated by the energy management policy and accuracy requirements for IoT applications. The proposed energy policy uses predictions of energy to be harvested and dictates the amount of energy that can be used by the edge device for deep learning inference. We compare the performance of our proposed approach with existing state-of-the-art CNNs and datasets using different filter-ranking criteria and pruning ratios.We observe that by using DRL driven pruning, the convolutional layers that consume relatively higher energy are pruned more as compared to their counterparts. Thereby, our approach outperforms existing approaches by reducing energy consumption and maintaining accuracy
Changing Tides or Freedom Fallacy? A Foucauldian Cautionary Reading of Women’s Professional Football’s Evolving Contexts
No full textA novel mid-infrared hollow waveguide gas sensor for measuring water vapor isotope ratios in the atmosphere
Get PDFA novel mid-infrared hollow waveguide gas sensor was developed to target H218O, H216O, H217O, and HDO absorption lines at 3662.9196, 3663.04522, 3663.32128, and 3663.84202 cm−1, respectively, based on wavelength modulation spectroscopy using a 2.73 µm distributed feedback diode laser. A hollow waveguide fiber with a 5-m length and 1-mm inner diameter was used for gas absorption. A dew point generator with liquid water with known water–isotope ratios was used to calibrate the sensor. Detection limits of 35.18 ppbv, 4.69 ppmv, 60.53 ppbv, and 3.88 ppbv were obtained for H218O, H216O, H217O, and HDO, respectively, in a 96-s integration time, which resulted in isotopic ratio measurement precision of 0.85‰, 0.57‰, and 10.48‰ for δ18O, δ17O, and δD, respectively. Field measurements of H218O, H216O, and H217O concentration were conducted on the Nanchang Hangkong University campus to evaluate sensor performance
Task-Load-Aware Game-Theoretic Framework for Wireless Federated Learning
Get PDFFederated learning (FL) can protect data privacy but has difficulties in motivating user equipment (UE) to engage in task training. This paper proposes a Bertrand-game based framework to address the incentive problem, where a model owner (MO) issues an FL task and the employed UEs help train the model by using their local data. Specially, we consider the impact of time-varying task load and channel quality on UE’s motivation to engage in the FL task. We adopt the finite-state discrete-time Markov chain (FSDT-MC) to predict these parameters during the FL task. Depending on the performance metrics set by the MO and the estimated energy cost of the FL task, each UE seeks to maximize its profit. We obtain the Nash equilibrium (NE) of the game in closed form, and develop a distributed iterative algorithm to find it. Finally, the simulation result verifies the effectiveness of the proposed approach
Paleoglaciology of the central East Antarctic Ice Sheet as revealed by blue-ice sediment
Get PDFWe present ∼100 cosmogenic surface exposure ages, including 75 new analyses, for a blue-ice moraine complex at Mt. Achernar, head of Law Glacier, in the central Transantarctic Mountains. The 10Be–3He–26Al ages along with previously-published boron concentrations chronicle past behavior of the East Antarctic Ice Sheet (EAIS) along the edge of the polar plateau since the sediments started to accumulate, around 0.5–1 Ma. Samples analyzed for 10Be from the Law Glacier surface record <100 years of exposure, indicating they likely have negligible inheritance when first exposed. The Law Glacier surface experienced relatively minor fluctuations in surface elevation throughout MIS 6 and 5, and likely during prior periods, as geomorphic features are intact and exposure ages are coherent on the moraine, ranging from ∼210 to ∼86 ka; respective means for MIS 5 till in two different areas are 106 ± 9.1 ka [n = 4 ages] and 106 ± 5.1 ka [n = 6]. Although we infer the Law Glacier has been relatively close to its current configuration generally since 0.5–1 Ma, disturbances to Achernar blue-ice moraine architecture seem apparent at times especially prior to the last two glacial cycles. The largest observed disturbance occurred when the nearby Lewis Cliffs Ice Tongue expanded either close to, or earlier than, 500-400 ka. A minimum ice thickness increase of 30 m is associated with the ∼20 ka blue-ice ridges, and a lateral moraine indicates the Law Glacier surface was ∼40–50 m higher at ∼9.2 ± 0.5 ka. Our findings support that lateral accretion over time formed the Mt. Achernar blue-ice moraine sequence, and by implication, other analogue Antarctic deposits. We interpret blue-ice moraines as representing, at times, relatively constant outlet glacier conditions and concur with prior studies that they reflect near-equilibrium forms. Blue-ice sediments are an underutilized and dateable paleoglaciologic and paleoclimate archive in Antarctica, including for former ice surface dynamics and possibly as a repository of old ice during periods such as MIS 5 and prior
Understanding the challenges and impact of training on referral of postnatal women to a community physical activity programme by health professionals: a qualitative study using the COM-B model
Get PDFObjective
To understand the value of training for health professionals for improving their ability to effectively refer postnatal women to a targeted community physical activity programme. The study also sought to understand challenges to effective referral of postnatal women from deprived areas.
Design, setting and participants
Semi-structured interviews were conducted in January-February 2020 with early years practitioners (n = 4), health visitors (n = 1) and community midwives (n = 2) who had participated in a training workshop implemented as part of a targeted community physical activity referral programme for postnatal women from deprived areas in the North East of England. Two follow up interviews were also conducted with one midwife and one early years practitioner during the Covid-19 pandemic. Data were analysed thematically and the Capability, Opportunity, Motivation, Behaviour (COM-B) model was employed to facilitate identification of the impact of training and the challenges in referral from the health professionals’ perspective.
Findings
The training increased capability to refer by improving knowledge and confidence of health professionals in being able to give appropriate guidance to postnatal women about physical activity without having to refer to other professionals. Health professionals reported adequate opportunities to engage with postnatal women, were motivated to refer and perceived this to be part of their role. The timing and method of message delivery were key contexts for perceived successful referral, particularly for midwives who wanted to ensure the messaging began in the antenatal period. Low staffing levels, limited interprofessional collaboration and finding strategies to engage women from deprived areas were key challenges to effective delivery of physical activity messages. These challenges were exacerbated during Covid-19, with increased mental health issues amongst postnatal women.
Key conclusions and implications for practice
Training health professionals for physical activity messaging can be a useful way to increase capability, opportunity, and motivation to refer to physical activity interventions for postnatal women in deprived areas to potentially increase physical wellbeing and reduce postnatal depression. The COM-B is a relevant framework to underpin training. A clearly identified referral pathway and staffing issues need to be addressed to improve referrals by health professionals
The Specific Evidence Rule: Reference Classes – Individuals – Personal Autonomy
Get PDFThis paper grapples with the issue of naked statistical evidence in general and the reference class problem (RCP) in particular. By analysing the reasoning patterns underlying the RCP, I will show, first, that the RCP rests on theoretical presuppositions which we are by no means bound to accept. Such a presupposition is is, what I will call, the wholesale approach in decision-making. Sec-ondly, I will show that the very effort to increase the level of precision to a maximum so that a refer-ence class contains a single member only is theoretically inconsistent insofar, as it deprives reference classes of their general (and thus scientific) character. Thereupon, I will argue, thirdly, that the de-cision to enact a specific evidence rule is a political one and reflects deep moral and jurisprudential values, not scientific propositions. Such a value is personal autonomy, which I go on to illuminate briefly. Whether the trier of fact will treat cases in a wholesale approach or not depends on consti-tutional arrangements and legal values putting emphasis on the individual and the latter’s dignity
More-than-human encounters with fish in the city: from careful angling practice to deadly indifference
Get PDFAngling is an immensely significant leisure practice that provides an important window onto the variable and selective ways humans value animals, and on how humans and animals variously affect each other’s lives. Through a novel ethnography of coarse angling practice, this paper focuses on the simultaneity of coarse fish as victims of human play and as biosocial actors with considerable affective power above and below water. We posit that paying close attention to the embodied and performative contexts of catching and caring for fish for leisure reveals deeply rooted passions and paradoxes that raise questions not only about angling but about the stark injustices within the spectrum of human-fish encounters. We conclude by asking whether angling should be consigned to history or whether anglers are important socio-ecological practitioners that could and should do more to challenge the cruelties and injustices within human-fish relations
The Water Absorption and Thermal Properties of Green Pterocarpus Angolensis (Mukwa)-Polylactide Composites
Get PDFThe water absorption, chemical resistance, and biological properties are contributing factors to the overall performance of bio-composites, especially for outdoor applications. The functional properties of bio-composites are dependent on the interfacial bonding mechanism, which is controlled by the surface modification and processing parameters of natural fibers. Therefore, this study aims to investigate the potential of enhancing the mukwa/polylactide (mukwa/PLA) interface through an economic and ecological surface modification of recycled mukwa wood fibers via alkali-laccase modification. The fabricated bio-composites intended for making durable farm poles for semi-arid conditions of Southern Africa were characterized via water absorption, chemical resistance, thickness swelling, hardness, and thermal properties. Less thickness swelling and water absorption were found on the alkali-laccase/PLA composites. The less-dense (1.09 g/cm3) alkali-laccase treated composites showed better chemical resistance. Much swelling of the composites was observed on the 40% nitric acid (HNO3), while 60%NaOH shrunk the composites and PLA by <3.5%. The laccase/PLA bio-composite showed a maximum thermal stability of 733 °C. The activation energy (Ea) optimized on the laccase/PLA composite with the highest of 104 kJ mol−1. Maximum crystallinity of 45.8% was achieved on the untreated/PLA composites. The alkali-laccase modification maximized the hardness of composites with 35.45 HV on alkali-laccase/PLA
An Active Bacterial Anti-adhesion Strategy Based on Directional Transportation of Bacterial Droplets Driven by Triboelectric Nanogenerators
Get PDFAn active bacterial anti-adhesion strategy based on directional transportation of bacterial droplets driven by a triboelectric nanogenerator (TENG) has not been reported to date, although passive defense approaches can prevent bacterial adhesion by regulating superwetting surfaces combined with incorporated antibacterial substances. Here a triboelectric nanogenerator driving droplet system (TNDDS) was built to drive directional transportation of bacterial droplets to be eliminated, which comprises TENG with periodical frictional Kapton film and aluminum foils and a superhydrophobic driving platform (SDP) with paralleled driving electrodes. The current generated by the TENG triboelectricity is transmitted to the paralleled driving electrodes to form an electric field driving the directional transportation of charged droplets. The critical value of the driven droplet volume on SDP is closely related to the distributed electrodes’ distance and width, and the driving distance of droplets is related to the number of electrodes. More crucially, TNDDS can actively drive the charged droplets of prepared triangular silver nanoprisms (Ag NPs) forward and back to mix with and remove a tiny bacterial droplet on an open SDP or in a tiny semi-enclosed channel. Bacteria could be killed by releasing Ag+ and effectively removed by TNDDS by regulating the motion direction. Generally, this approach offers a promising application for removing bacteria from material surfaces driven by TENG and opens a new avenue for bacterial anti-adhesion