Earlier Work Research Articles

From Circle to Cycloid: The Philosophical Value of Religious Cult in Maurice Blondel’s L’Action

This article explores Maurice Blondel’s (1861–1949) later notion of the “cycloid” of thought, particularly as this helps us to understand his earlier work L’Action (1893). The aim is to demonstrate how Blondel incorporates aspects of the Christian faith, particularly the Eucharist, into his philosophy without abrogating his “method of immanence”. In particular, the article shows how Blondel saw attention to the Christian spirit as essential to the development of a metaphysics that attends both to finite actions and to the action of God, actus purus.

Training Object Detectors from Scratch: An Empirical Study in the Era of Vision Transformer

AbstractModeling in computer vision has long been dominated by convolutional neural networks (CNNs). Recently, in light of the excellent performance of self-attention mechanism in the language field, transformers tailored for visual data have drawn significant attention and triumphed over CNNs in various vision tasks. These vision transformers heavily rely on large-scale pre-training to achieve competitive accuracy, which not only hinders the freedom of architectural design in downstream tasks like object detection, but also causes learning bias and domain mismatch in the fine-tuning stages. To this end, we aim to get rid of the “pre-train and fine-tune” paradigm of vision transformer and train transformer based object detector from scratch. Some earlier works in the CNNs era have successfully trained CNNs based detectors without pre-training, unfortunately, their findings do not generalize well when the backbone is switched from CNNs to a vision transformer. Instead of proposing a specific vision transformer based detector, in this work, our goal is to reveal the insights of training vision transformer based detectors from scratch. In particular, we expect those insights to help other researchers and practitioners, and inspire more interesting research in other fields, such as remote sensing, visual-linguistic pre-training, etc. One of the key findings is that both architectural changes and more epochs play critical roles in training vision transformer based detectors from scratch. Experiments on the MS COCO dataset demonstrate that vision transformer based detectors trained from scratch can also achieve similar performance to their counterparts with ImageNet pre-training.

High temperature tribological response of Fe-2Cu-0.8C-CaF2 self-lubricating composites at high speeds

In this work, Fe-2Cu-0.8C-CaF2 self-lubricating composites with calcium fluoride solid lubricant (3 □ 12 wt.%) were examined for their friction and wear at 5 and 10 m/s, at 500 °C. Addition of CaF2 decreased density and hardness of composites. During sliding, materials gained weight due to oxidation. Compared to the base matrix (Fe-2Cu-0.8C), composites showed lower weight gain and lower coefficient of friction. Increase in porosity with CaF2 content increased oxidation resulting in higher weight gain and increased friction due to wear debris abrasion. Increase in speed reduced weight gain due to higher material loss. Adhesion was the dominant wear mechanism in base matrix; delamination and wear debris abrasion in composites. Temperature rise at sliding surfaces was theoretically estimated. Increase in speed increased temperature, which reduced friction due to softening and shearing of solid lubricant. Composite with 3 wt.% CaF2 showed least surface damage and 6 wt.% showed lowest coefficient of friction, i.e., lower by 16% and 10% at 5, 10 m/s than base matrix. Tribological response of the composites to a broad range of applied parameters, viz. speed, load and temperature taken from earlier works and present work is briefly summarized. The study suggests the dominant role of CaF2 content and the wear debris in altering the tribological response. Further, the stability of the developed composites at high temperature and high load conditions was also established. The study suggests that the developed composites could serve high-load and high-temperature applications for heavy machinery such as bearings, shafts and gears.

An Overview of Maternity healthcare Monitoring in Developing Nations

A healthcare monitoring arrangement is essential for frequently monitoring a patient's health status. Specifically, maternal healthcare systems for tracking are utilized to evaluate the clinical status and monitor any abnormal condition changes during all three trimesters. This paper's objective is to conduct an extensive literature review and acknowledge earlier initiatives and studies conducted previously in maternal health care monitoring. This review focuses on accumulating information from earlier work and presents a general overview of previous studies concerning maternal health care monitoring (MHCM). The paper focuses on the maternal healthcare systems in developing countries accessed by pregnant women during the antenatal period. Furthermore, this paper highlights the challenges in the maternal health sector that include inadequate work conditions for health workers, home-based birth practices, long distances to healthcare facilities, and long waiting times in health facilities. The paper indicates the potential opportunities to strengthen maternal healthcare services and allow effective access to maternal healthcare facilities by pregnant women.

Labor organizing at chokepoints along Amazon’s supply chain: Locating geo-strategic nodes

Amazon seems to be creating a new hybrid model of capitalism combining some elements of classical Fordist vertical integration, or even the over hundred-year-old “Taylorism” of scientific management, with 21st century elements of labor “flexibility” and reliance on gig labor and subcontracting. This hybrid model offers opportunities for organized labor to gain a foothold within some of Amazon’s vertically integrated nodes as the firm lengthens its corporate commodity chain to grow increasingly close to consumers. Building on earlier work on opportunities for, and constraints on, labor in a variety of global commodity chains, our empirical cases examine how Amazon’s corporate strategies may open opportunities for labor in three illustrative cases ensconced in fulfillment centers—the Fordist vertical integration side of the model—in the Inland Empire and Otay Mesa (both in southern California) and Northern Kentucky.

The Weight of the World

ABSTRACT This essay focuses upon MIchel Serres’s etymological connection between peser (to weigh) and penser (to think, or judge). I take Serres to mean the weight of the world is a judging or rendering that takes place without human intention, but which places us into a new relation with the world itself. This shift occurs in his notion of the ‘parasite’ as ‘noise’, meaning the noise of the world in its complexity, and also as a ‘third’ that shifts the balance of relationships that compose the world. Such is the complexity of ‘things’: tangles of relations from which human experience and thinking first arise. The background noise of Serres’s earlier work is the confluence of science and violence whose emblematic event, its ‘third’, is the bombing of Hiroshima, whereas his later work concerns the noise of the climate crisis. In tracing this shift, I emphasize Serres’s identification with Hermes, the deliverer of messages. The point of messages is not to understand them but to receive their transmission. I suggest that Serres’s work is to intervene in this transmission: it is a parasitic performance aiming to deliver new messages and to change the balance in our relation to things.

One-Step Replica Symmetry Breaking of Random Regular NAE-SAT II

Continuing our earlier work in Nam et al. (One-step replica symmetry breaking of random regular NAE-SAT I, arXiv:2011.14270, 2020), we study the random regular k-nae-sat model in the condensation regime. In Nam et al. (2020), the (1rsb) properties of the model were established with positive probability. In this paper, we improve the result to probability arbitrarily close to one. To do so, we introduce a new framework which is the synthesis of two approaches: the small subgraph conditioning and a variance decomposition technique using Doob martingales and discrete Fourier analysis. The main challenge is a delicate integration of the two methods to overcome the difficulty arising from applying the moment method to an unbounded state space.

Significant Absences: Wittgenstein’s Philosophy of Silence and Joyce’s Poetics of the Unspoken


 
 
 This paper discusses an important phase in Ludwig Wittgenstein’s analytic philosophy through a comparative examination of the profound correspondences that exist between his concept of silence and the poetics of another crucial authorial figure of the 20th century: James Joyce. Based on the hypothesis that there are striking resemblances between their early works, that is, between Joyce’s realistic short-story collection Dubliners and Wittgenstein’s Tractatus Logico-Philosophicus, the article employs mostly close-reading, analytical-interpretative and comparative methods. It argues that silence was an intentional intellectual, aesthetic and ethical choice of both these authors, their way to preserve the autonomy of metaphysics and to honour the beauty of the unspoken.
 Starting from their common critical treatment of the habitual and largely alienated speech, the discussion connects Wittgenstein’s philosophical attitudes regarding the imprecision and inadequacy of every-day language and Joyce’s notion of ‘spiritual paralysis’ of the city-life, which he saw as the main motive for writing his collection about fin-desiècle Dublin. On the grounds of their shared views about the limits of words, behind which there are worlds that cannot be properly uttered, the idea of silence – or the highly significant narrative absence – grows to permeate the work of both. In the case of Wittgenstein, it is a call for a new philosophy, or anti-philosophy, which in negating metaphysics in effect preserves its independence from a discursive speech which cannot express it, whereas in the case of Joyce, correspondingly (and almost simultaneously), it is a quest for a new literary mode that will foreground a particular Modernist allusiveness, rhetoric of omission and deliberately incomplete, gnomonical narrative structures.
 
 

An undecidable statement regarding zero-sum games

In this paper, we give an example of a statement concerning two-player zero-sum games which is undecidable, meaning that it can neither be proven or disproven by the standard axioms of mathematics. Earlier work has shown that there exist “paradoxical” two-player zero-sum games with unbounded payoffs, in which a standard calculation of the two players' expected utilities of a mixed strategy profile yield a positive sum. We show that whether or not a modified version of this paradoxical situation, with bounded payoffs and a weaker measurability requirement, exists is an unanswerable question. Our proof relies on a mixture of techniques from set theory and ergodic theory.

Effect of size on expression of bistability in mouse spinal motoneurons.

Bistability in spinal motoneurons supports tonic spike activity in the absence of excitatory drive. Earlier work in adult preparations suggested that smaller motoneurons innervating slow antigravity muscle fibers are more likely to generate bistability for postural maintenance. However, whether large motoneurons innervating fast-fatigable muscle fibers display bistability is still controversial. To address this, we examined the relationship between soma size and bistability in lumbar (L4-L5) ventrolateral α-motoneurons of choline acetyltransferase (ChAT)-green fluorescent protein (GFP) and Hb9-GFP mice during the first 4 wk of life. We found that as neuron size increases, the prevalence of bistability rises. Smaller α-motoneurons lack bistability, whereas larger fast α-motoneurons [matrix metalloproteinase-9 (MMP-9)+/Hb9+] with a soma area ≥ 400 µm2 exhibit significantly higher bistability. Ionic currents associated with bistability, including the persistent Nav1.6 current, the thermosensitive Trpm5 Ca2+-activated Na+ current, and the slowly inactivating Kv1.2 current, also scale with cell size. Serotonin evokes full bistability in large motoneurons with partial bistable properties but not in small motoneurons. Our study provides important insights into the neural mechanisms underlying bistability and how motoneuron size correlates with bistability in mice.NEW & NOTEWORTHY Bistability is not a common feature of all mouse spinal motoneurons. It is absent in small, slow motoneurons but present in most large, fast motoneurons. This difference results from differential expression of ionic currents that enable bistability, which are highly expressed in large motoneurons but small or absent in small motoneurons. These results support a possible role for fast motoneurons in maintenance of tonic posture in addition to their known roles in fast movements.

Биографический миф о М. Горьком и художественная реальность: драматическая трилогия Н. Прибутковской «Три версии одной судьбы. Пьесы»

The aim of the research is to characterize the ways of interpreting biographical myths about M. Gorky based on the analysis of N. Pributkovskaya’s dramatic cycle “Three versions of one fate”. The origins of formation of the future writer’s worldview, his relationship with E. P. Peshkova, as well as the reasons for Gorky’s moral crisis in the last years of his life are developed as the debatable positions of Gorky’s biographical myth. The article deals with the main qualifiers of the artistic world of the plays, the logic of the plot of the trilogy, and the principles for selecting facts from the writer’s biography. Scientific novelty consists in introducing into scientific use the plays created using unpublished materials from M. Gorky’s personal correspondence, a comprehensive analysis of the trilogy as an artistic unity carried out for the first time, since there are currently no literary studies devoted to N. Pributkovskaya’s dramaturgy. As a result of the research, the specificity of the trilogy genre has been determined as a synthesis of various types of documentary nature: epistolary (human document), models of artistic personal identification (the writer’s early works), documentary topoi (Nizhny Novgorod at the end of the 19th century). It is shown that the subjectivity and evaluativeness of the author’s position appeals to the perceptive consciousness of the modern reader/viewer, indicating a change in the ontological status of Gorky’s myth.

Optical Properties of AgAu Alloy Clusters: Effect of Chemical Configuration along a Rearrangement Pathway

Gold and silver are, for all their chemical similarities, optically very different. Small Ag clusters show a localized surface-plasmon resonance (LSPR), whereas in Au clusters smaller than about 300 atoms, the resonance is absent due to the coupling with the interband transitions from the d electrons. This opens the possibility of tuning the cluster properties depending on their composition and chemical configuration. Earlier work on AgAu alloy clusters has shown that the outermost shell of atoms is crucial to their overall optical properties. In the present contribution, we consider the optical spectroscopic properties associated with the structural rearrangement in 55-atom AgAu alloy clusters in which the core transforms from pure silver to pure gold. Calculations using time-dependent density-functional theory are complemented by an in-depth study of the subtle effects that the chemical configuration has on the details of the materials’ d bands. Although the cluster surface remains alloyed, the geometrical changes translate into strong variations in the optical properties.

Multistate Compound Magnetic Tunnel Junction Synapses for Digital Recognition.

The quest to mimic the multistate synapses for bioinspired computing has triggered nascent research that leverages the well-established magnetic tunnel junction (MTJ) technology. Early works on the spin transfer torque MTJ-based artificial neural network (ANN) are susceptible to poor thermal reliability, high latency, and high critical current densities. Meanwhile, work on spin-orbit torque (SOT) MTJ-based ANN mainly utilized domain wall motion, which yields negligibly small readout signals differentiating consecutive states and has designs that are incompatible with technological scale-up. Here, we propose a multistate device concept built upon a compound MTJ consisting of multiple SOT-MTJs (number of MTJs, n = 1-4) on a shared write channel, mimicking the spin-based ANN. The n + 1 resistance states representing varying synaptic weights can be tuned by varying the voltage pulses (±1.5-1.8 V), pulse duration (100-300 ns), and applied in-plane fields (5.5-10.5 mT). A large TMR difference of more than 13.6% is observed between two consecutive states for the 4-cell compound MTJ, a 4-fold improvement from reported state-of-the-art spin-based synaptic devices. The ANN built upon the compound MTJ shows high learning accuracy for digital recognition tasks with incremental states and retraining, achieving test accuracy as high as 95.75% in the 4-cell compound MTJ. These results provide an industry-compatible platform to integrate these multistate SOT-MTJ synapses directly into neuromorphic architecture for in-memory and unconventional computing applications.

On quasicomplete k$k$‐surfaces in 3‐dimensional space‐forms

AbstractIn the study of immersed surfaces of constant positive extrinsic curvature in space‐forms, it is natural to substitute completeness for a weaker property, which we here call quasicompleteness. We determine the global geometry of such surfaces under the hypotheses of quasicompleteness. In particular, we show that, for , the only quasicomplete immersed surfaces of constant extrinsic curvature equal to in the 3‐dimensional space‐form of constant sectional curvature equal to are the geodesic spheres. Together with earlier work of the author, this completes the classification of quasicomplete immersed surfaces of constant positive extrinsic curvature in 3‐dimensional space‐forms.

Chemical mechanical polishing for indium bond pad damascene processing

We investigated chemical mechanical polishing (CMP) of indium, with the goal of obtaining indium bond pads for later cryo-3D integration of quantum computing-related chips, through bonding between these bond pads and indium bumps. Higher removal rates were obtained with soft CMP pads than with hard pads. The latter led to deep scratching, while this effect was much more limited for soft pad CMP. On patterned wafers, indium is cleared well in structured areas using soft pad CMP, leading to relatively high-quality indium surfaces inside bond pads, although corrosion might be of some concern. Pattern density uniformity was an important factor for within-die deviation in indium clearing time. Dishing was much more limited than in earlier work on indium polishing, while surface roughness was also found to be relatively limited. The obtained indium damascene bond pads may be suitable for 3D die-to-die and wafer-to-wafer bonding through indium pad-to-bump bonding.

A Source Identification Problem in a Bi-parabolic Equation: Convergence Rates and Some Optimal Results

This paper is concerned with identification of a spatial source function from final time observation in a bi-parabolic equation, where the full source function is assumed to be a product of time dependent and a space dependent function. Due to the ill-posedness of the problem, recently some authors have employed different regularization method and analysed the convergence rates. But, to the best of our knowledge, the quasi-reversibility method is not explored yet, and thus we study that in this paper. As an important implication, the Hölder rates for the apriori and aposteriori error estimates obtained in this paper improve upon the rates obtained in earlier works. Also, in some cases we show that the rates obtained are of optimal order. Further, this work seems to be the first one that has broaden the applicability of the problem by allowing the time dependent component of the source function to change sign. To the best of our knowledge, the earlier known work assumed the fixed sign of the time dependent component by assuming some bounded below condition.

Optimisation of Biogas Production in the Co-Digestion of Pre-Hydrodynamically Cavitated Aerobic Granular Sludge with Waste Fats

The characteristics of excess aerobic granular sludge, related to its structure and chemical composition, limit the efficiency of anaerobic digestion. For this reason, pre-treatment methods and compositions with other organic substrates are used. In earlier work, no attempt was made to intensify the methane fermentation of the excess aerobic granular sludge by adding fatty waste materials. The aim of the research was to determine the effects of co-digestion of pre-hydrodynamically cavitated aerobic granular sludge with waste fats on the efficiency of methane fermentation under mesophilic and thermophilic conditions. The addition of waste fats improved the C/N ratio and increased its value to 19. Under mesophilic conditions, the highest effects were observed when the proportion of volatile solids from waste fats was 25%. The amount of biogas produced increased by 17.85% and CH4 by 19.85% compared to the control. The greatest effects were observed in thermophilic anaerobic digestion at 55 °C, where a 15% waste fat content in volatile solids was ensured. This resulted in the production of 1278.2 ± 40.2 mL/gVS biogas and 889.4 ± 29.7 mL/gVS CH4. The CH4 content of the biogas was 69.6 ± 1.3%. The increase in biogas and CH4 yield compared to pure aerobic granular sludge anaerobic digestion was 34.4% and 40.1%, respectively. An increase in the proportion of waste fats in the substrate had no significant effect on the efficiency of methane fermentation. Strong positive correlations (R2 > 0.9) were observed between biogas and CH4 production and the C/N ratio and VS concentration.

A generating absorbing boundary condition for simulating wave interaction with maritime structures in current or at forward speed

The lack of suitable boundary conditions in practical surface wave simulations with maritime structures in current or at forward speed may cause energy in the computational domain to accumulate due to spurious wave reflection. The common way to prevent wave reflection is to use passive wave absorbers, such as damping zones or relaxation zones, which requires larger domains at the cost of computational effort. Our goal is to derive a local generating absorbing boundary condition (GABC) for long-crested irregular waves on top of a mean flow, using the flow to model the forward speed of a structure such as a ship. Earlier work has demonstrated that a local GABC for free surface waves has a performance similar to passive wave absorbers, but at a reduced computational effort. New in the present work is that we extend, verify and validate the GABC in the presence of a nonzero mean flow. The GABC is designed to be accurate for a range of wave components in irregular sea states, with the resulting reflection coefficients for each component lower than a chosen value, say 5%. Having used potential flow theory for its derivation means that the boundary should not be placed at the exact location where wave breaking is expected, such as very close to the structure in the domain, or in the surf zone in coastal modeling. For the application with ships in this article that does not pose a limitation. The performance is demonstrated for a range of dimensionless wave number between 0 and 6. Such a boundary condition is obtained through a rational approximation of the linear dispersion relation with a mean flow, in combination with vertical derivatives of the solution variables along the boundary. Local linearization means that the GABC incorrectly considers bound, nonlinear wave components to be freely propagating wave components. Bound components, however, tend to have smaller amplitudes and do not appear to affect performance for the considered cases. Results of simulations with regular and irregular waves, on top of flows with different magnitudes and directions, are found to agree with the theory. The main source of differences is the implementation of the second derivate in the GABC near the free surface. Simulations of a Wigley hull at forward speed in irregular waves are compared to an experiment that was conducted specifically for validating the ABC. The data of the experiment are available as open data through doi: 10.4121/21320604. The comparison between simulation and experiment demonstrates that the GABC with a mean flow can be applied not only for theoretical simulations with propagating waves, but also for more practical applications with a structure in the domain.

Modality matters: Three auditory conflict tasks to measure individual differences in attention control.

Early work on selective attention used auditory-based tasks, such as dichotic listening, to shed light on capacity limitations and individual differences in these limitations. Today, there is great interest in individual differences in attentional abilities, but the field has shifted towards visual-modality tasks. Furthermore, most conflict-based tests of attention control lack reliability due to low signal-to-noise ratios and the use of difference scores. Critically, it is unclear to what extent attention control generalizes across sensory modalities, and without reliable auditory-based tests, an answer to this question will remain elusive. To this end, we developed three auditory-based tests of attention control that use an adaptive response deadline (DL) to account for speed-accuracy trade-offs: Auditory Simon DL, Auditory Flanker DL, and Auditory Stroop DL. In a large sample (N = 316), we investigated the psychometric properties of the three auditory conflict tasks, tested whether attention control is better modeled as a unitary factor or modality-specific factors, and estimated the extent to which unique variance in modality-specific factors contributed incrementally to the prediction of dichotic listening and multitasking performance. Our analyses indicated that the auditory conflict tasks have strong psychometric properties and demonstrate convergent validity with visual tests of attention control. Auditory and visual attention control factors were highly correlated (r = .81)-even after controlling for perceptual processing speed (r = .75). Modality-specific attention control factors accounted for unique variance in modality-matched criterion measures, but the majority of the explained variance was modality-general. The results suggest an interplay between modality-general attention control and modality-specific processing.

Frontal midline theta transcranial alternating current stimulation enhances early consolidation of episodic memory

Evidence implicating theta rhythms in declarative memory encoding and retrieval, together with the notion that both retrieval and consolidation involve memory reinstatement or replay, suggests that post-learning theta rhythm modulation can promote early consolidation of newly formed memories. Building on earlier work employing theta neurofeedback, we examined whether theta-frequency transcranial alternating stimulation (tACS) can engender effective consolidation of newly formed episodic memories, compared with beta frequency stimulation or sham control conditions. We compared midline frontal and posterior parietal theta stimulation montages and examined whether benefits to memory of theta upregulation are attributable to consolidation rather than to retrieval processes by using a washout period to eliminate tACS after-effects between stimulation and memory assessment. Four groups of participants viewed object pictures followed by a free recall test during three study-test cycles. They then engaged in tACS (frontal theta montage/parietal theta montage/frontal beta montage/sham) for a period of 20 min, followed by a 2-h break. Free recall assessments were conducted after the break, 24 h later, and 7 days later. Frontal midline theta-tACS induced significant off-line retrieval gains at all assessment time points relative to all other conditions. This indicates that theta upregulation provides optimal conditions for the consolidation of episodic memory, independent of mental-state strategies.