bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epidemic changepoint detection in the presence of nuisance changes
Authors: Juodakis Julius , Marsland Stephen 
Published: April 2022

AbstractMany time series problems feature epidemic changes—segments where a parameter deviates from a background baseline. Detection of such changepoints can be improved by accounting for the epidemic structure, but this is currently difficult if the background level is unknown. Furthermore, in practical data the background often undergoes nuisance changes, which interfere with standard estimation techniques and appear as false alarms. To solve these issues, we develop a new, efficient approach to simultaneously detect epidemic changes and estimate unknown, but fixed, background level, based on a penalised cost. Using it, we build a two-level detector that models and separates nuisance and signal changes. The analytic and computational properties of the proposed methods are established, including consistency and convergence. We demonstrate via simulations that our two-level detector provides accurate estimation of changepoints under a nuisance process, while other state-of-the-art detectors fail. In real-world genomic and demographic datasets, the proposed method identified and localised target events while separating out seasonal variations and experimental artefacts.
Surface ocean current variations in the North Pacific related to Arctic stratospheric ozone
Authors: Wang Tao , Tian Wenshou , Zhang Jiankai , Xu Mian , Lian Tao , Hu Dingzhu , Qie Kai 
Published: April 2022

AbstractUsing reanalysis datasets and a coupled general circulation model, the relationship between springtime Arctic total column ozone (TCO) and surface (5 m) ocean currents in the North Pacific is investigated. We found that as March Arctic TCO decreases, a statistically significant northwestward ocean current anomaly occurs in the northern North Pacific in surface layer, but an anomalous southward ocean current appears in the central North Pacific in April, and vice versa. The decreased Arctic TCO favors an enhanced Arctic stratospheric circulation, which tends to induce the tropospheric positive Arctic Oscillation anomaly with easterly anomalies over the midlatitude eastern Asia in late March through stratosphere-troposphere dynamical coupling. The easterly anomaly over eastern Asia in late March further extends eastward and induces an easterly anomaly over the midlatitude North Pacific, which favors negative North Pacific Oscillation (–NPO)-like circulation anomaly via anomalous zonal wind shear and the interactions between synoptic scale eddies and the mean flow in early-middle April. The –NPO anomaly forces anomalous northwestward/southward surface ocean currents in the northern/central North Pacific through direct friction of wind and the Coriolis force. Our coupled numerical simulations with high- and low-ozone scenarios also support that the Arctic stratospheric ozone affects the North Pacific surface ocean currents by NPO anomalies. Moreover, the ozone-related ocean current anomalies contribute to Victoria mode-like sea surface temperature anomalies in the North Pacific by horizontal heat advection. These results imply that Arctic ozone signal could be a predictor for variations of the North Pacific surface ocean currents.
Blitzschutz von Hochspannungs-Freiluftschaltanlagen – praktische Auslegung
Authors: Schober Bernhard , Schwalt Lukas , Pack Stephan 
Published: April 2022

ZusammenfassungDer Blitzschutz von Hochspannungs-Schaltanlagen liefert einen wesentlichen Beitrag für den zuverlässigen Betrieb unserer Hochspannungssysteme. Da Schaltanlagen die Knotenpunkte der elektrischen Verteil- und Übertragungsnetze darstellen, können direkte Blitzeinschläge zu Beeinträchtigungen der Versorgungssicherheit und des zuverlässigen Betriebs dieser Anlagen führen. In diesem Zusammenhang sind besonders Hochspannungs-Freiluftschaltanlagen den direkten Einwirkungen von Blitzentladungen ausgesetzt, da sich deren spannungsführende Anlagenteile im Freien und in exponierter Lage befinden. Der Blitzschutz von baulichen Anlagen und Personen ist in der Norm ÖVE/ÖNORM EN 62305‑3 definiert. Die Norm bietet unter anderem verschiedene Methoden für die Auslegung des Blitzschutzes und kann auch auf Freiluftschaltanlagen umgelegt werden. Andererseits werden in der Norm ÖVE/ÖNORM EN 61936‑1 die Anforderungen an Hochspannungsanlagen behandelt, wie beispielsweise Mindestabstände und Mindesthöhen von aktiven Teilen sowie die Definition einer Gefahrenzone. Am Beispiel der praktischen Auslegung des äußeren Blitzschutzes einer 380-kV-Hochspannungs-Freiluftschaltanlage werden beide Normen miteinander kombiniert.
Triggered Seismicity in a Flooded Former Coal Mining Basin (Gardanne Area, France)
Authors: Dominique Pascal , Aochi Hideo , Morel Jacques 
Published: April 2022

AbstractWe studied the correlation between seismicity and the water table level in an abandoned coal mine (Bouches-du-Rhône, France), closed in 2003, where groundwater has been pumped out since 2010 to prevent underground flooding. Microseismicity was first felt by the population in 2010 and a strongly felt seismic swarm occurred in November 2012. The origin of the seismicity was therefore questioned, in relation to both the potential instability of old, shallow galleries that might generate damage at the surface and a local seismic hazard assessment. A temporary dense seismic network in the area allowed us to analyse the spatial distribution of the seismicity in detail. Most of the seismicity was clearly located under the mine workings, highlighting that an existing fault system crossing the mining operation was being hydraulically activated, in accordance with the known tectonic extension regime. Our analysis clearly shows a spatiotemporal relationship between seismic migration and the level of the mine aquifer between 2013 and 2017. Thus, seismicity will persist with oscillations of the mining aquifer, depending on the pumping capacities and effective rainfall. Continuous hydraulic and seismic monitoring is necessary to better understand these phenomena and assess the associated risks.
Linear/Ridge expansions: enhancing linear approximations by ridge functions
Authors: Greif Constantin , Junk Philipp , Urban Karsten 
Published: April 2022

AbstractWe consider approximations formed by the sum of a linear combination of given functions enhanced by ridge functions—a Linear/Ridge expansion. For an explicitly or implicitly given objective function, we reformulate finding a best Linear/Ridge expansion in terms of an optimization problem. We introduce a particle grid algorithm for its solution. Several numerical results underline the flexibility, robustness and efficiency of the algorithm. One particular source of motivation is model reduction of parameterized transport or wave equations. We show that the particle grid algorithm is able to find a Linear/Ridge expansion as an efficient nonlinear model reduction.
Exploring the influence of a user-specific explainable virtual advisor on health behaviour change intentions
Authors: Abdulrahman Amal , Richards Deborah , Bilgin Ayse Aysin 
Published: April 2022

AbstractVirtual advisors (VAs) are being utilised almost in every service nowadays from entertainment to healthcare. To increase the user’s trust in these VAs and encourage the users to follow their advice, they should have the capability of explaining their decisions, particularly, when the decision is vital such as health advice. However, the role of an explainable VA in health behaviour change is understudied. There is evidence that people tend to change their intentions towards health behaviour when the persuasion message is linked to their mental state. Thus, this study explores this link by introducing an explainable VA that provides explanation according to the user’s mental state (beliefs and goals) rather than the agent’s mental state as commonly utilised in explainable agents. It further explores the influence of different explanation patterns that refer to beliefs, goals, or beliefs&goals on the user’s behaviour change. An explainable VA was designed to advise undergraduate students how to manage their study-related stress by motivating them to change certain behaviours. With 91 participants, the VA was evaluated and the results revealed that user-specific explanation could significantly encourage behaviour change intentions and build good user-agent relationship. Small differences were found between the three types of explanation patterns.
Self-organizing migrating algorithm: review, improvements and comparison
Authors: Skanderova Lenka 
Published: April 2022

AbstractThe self-organizing migrating algorithm (SOMA) is a population-based meta-heuristic that belongs to swarm intelligence. In the last 20 years, we can observe two main streams in the publications. First, novel approaches contributing to the improvement of its performance. Second, solving the various optimization problems. Despite the different approaches and applications, there exists no work summarizing them. Therefore, this work reviews the research papers dealing with the principles and application of the SOMA. The second goal of this work is to provide additional information about the performance of the SOMA. This work presents the comparison of the selected algorithms. The experimental results indicate that the best-performing SOMAs provide competitive results comparing the recently published algorithms.
Different perspectives on the b-plane: perturbation effects and use for resonant flyby design
Authors: Masat Alessandro , Romano Matteo , Colombo Camilla 
Published: April 2022

AbstractOrbital resonances can be leveraged in the mission design phase to target planets at different energy levels. On the other side, precise models are needed to predict possible threatening returns of natural and artificial objects closely approaching a target planet. To this aim, we propose a semi-analytic extension of the b-plane resonance model to account for perturbing effects inside the planet’s sphere of influence. We compute the actual values of the perturbing coefficients by means of precise numerical simulations, whereas their expression stems from the properties of hyperbolic trajectories and asymptotic planetocentric velocity vectors. We apply the proposed b-plane model to design ballistic resonant flybys by solving a multilevel mixed-integer nonlinear optimization problem.
Associations between steady-state pattern electroretinography and estimated retinal ganglion cell count in glaucoma suspects
Authors: Tirsi Andrew , Orshan Derek , Wong Benny , Gliagias Vasiliki , Tsai Joby , Obstbaum Stephen A. , Tello Celso 
Published: April 2022

AbstractPurposeTo estimate retinal ganglion cell (RGC) count in glaucoma suspects (GS) and ascertain its relationships with steady-state pattern electroretinography (ssPERG) parameters.MethodsIn this prospective cross-sectional study, 22 subjects (44 eyes) were recruited at the Manhattan Eye, Ear, and Throat Hospital. Subjects underwent complete eye examinations, optical coherence tomography, standard automated perimetry, and ssPERG testing. Eyes were divided into two groups based upon clinical data: healthy subjects and GS. RGC count was estimated using the combined structure–function index.ResultsEstimated RGC count, average retinal nerve fiber layer thickness (ARNFLT), and average ganglion cell layer and inner plexiform layer thickness (GCIPLT) were reduced in GS eyes (p ≤ 0.001for all parameters). Pearson correlations revealed that ssPERG magnitude and magnitudeD correlated with ARNFLT(r ≥ 0.53, p < 0.001), GCIPLT(r > 0.38, p < 0.011), and estimated RGC count(r > 0.46, p < 0.002).Six mediation analyses revealed that estimated RGC count mediated the relationships among ssPERG parameters, ARNFLT, and GCIPLT.ConclusionSteady-state PERG parameters demonstrated linear correlations with estimated RGC count. The associations among ssPERG parameters and structural measures were mediated by estimated RGC count.
Mobile-assisted language learning in Chinese higher education context: a systematic review from the perspective of the situated learning theory
Authors: Li Fan , Fan Si , Wang Yanjun 
Published: April 2022

AbstractRecent years have witnessed numerous systematic investigations on mobile-assisted language learning (MALL). However, very few research synthesis studies focused on the higher education context in mainland China. This paper provides a systematic review of the findings of 23 studies published between 2015 and 2020 in mainland China. The aim of this review is twofold: 1) to examine prevalent researched elements in extant MALL studies; and 2) to investigate ways in which the two original components of the Situated Learning Theory (SLT), including Legitimate Peripheral Participation and Communities of Practice (Lave & Wenger, 1991), have a bearing on MALL. This systematic review resulted in two major findings. First, five key researched elements were revealed, e.g., target language teaching areas, and adopted applications/software. Second, guided by the two original elements of SLT, four derived elements were identified, namely authenticity, social interactions and collaborations, apprenticeship learning, and beliefs and behaviours. The findings suggest the need to develop sound MALL pedagogies associated with sociocultural aspects of language learning in relevant contexts. This review study also provides insights into how Chinese language professionals and practitioners can improve curriculum design and resource development to adapt to future trends in MALL.
Teaching toddlers the meaning of numbers—connecting modes of mathematical representations in book reading
Authors: Björklund Camilla , Palmér Hanna 
Published: April 2022

AbstractIn this article, we direct attention to what becomes critical in teaching activities for toddlers (1–3-year-olds) to learn the meaning of numbers. One activity we thoroughly explore is interactive book reading, based on previous research indicating positive learning outcomes from this type of mathematical activity, as it has shown to simultaneously embrace the child’s perspective and encourage interaction and ‘number talk.’ A specially designed picture book presenting small quantities was developed, and variation theory principles were embedded in both the book design and the teaching acts. Through qualitative analyses, we aim to identify what is critical in the interactive book reading sessions for toddlers to discern essential aspects of numbers, with a specific focus on the conditions for making modes of representations into resources for learning. Preschool teachers frequently read the book to 27 toddlers over the course of a year. Video documentation of their reading sessions was analyzed, and exposed the significance of addressing the child’s perspective when choosing what representation to emphasize and in what ways connections within and between representations can be made. Thus, the study contributes knowledge on the teaching of numbers with toddlers, and problematizes as well as extends the potential of interactive book reading as a quality-enhancing educational tool.
Comparative Analysis of the Vocal Repertoires of the Indri (Indri indri) and the Diademed Sifaka (Propithecus diadema)
Authors: Valente Daria , Miaretsoa Longondraza , Anania Alessio , Costa Francesco , Mascaro Alessandra , Raimondi Teresa , De Gregorio Chiara , Torti Valeria , Friard Olivier , Ratsimbazafy Jonah , Giacoma Cristina , Gamba Marco 
Published: April 2022

AbstractStrepsirrhine vocalisations are extraordinarily diverse and cross-species comparisons are needed to explore how this variability evolved. We contributed to the investigation of primate acoustic diversity by comparing the vocal repertoire of two sympatric lemur species, Propithecus diadema and Indri indri. These diurnal species belong to the same taxonomic family and have similar activity patterns but different social structures. These features make them excellent candidates for an investigation of the phylogenetic, environmental, and social influence on primate vocal behavior. We recorded 3 P. diadema groups in 2014 and 2016. From 1,872 recordings we selected and assigned 3814 calls to 9 a priori call types, on the basis of their acoustic structure. We implemented a reproducible technique performing an acoustic feature extraction relying on frequency bins, t-SNE data reduction, and a hard-clustering analysis. We first quantified the vocal repertoire of P. diadema, finding consistent results for the 9 putatively identified call types. When comparing this repertoire with a previously published repertoire of I. indri, we found highly species-specific repertoires, with only 2% of the calls misclassified by species identity. The loud calls of the two species were very distinct, while the low-frequency calls were more similar. Our results pinpoint the role of phylogenetic history, social and environmental features on the evolution of communicative systems and contribute to a deeper understanding of the evolutionary roots of primate vocal differentiation. We conclude by arguing that standardized and reproducible techniques, like the one we employed, allow robust comparisons and should be prioritized in the future.
Exponentially Convergent Trapezoidal Rules to Approximate Fractional Powers of Operators
Authors: Aceto Lidia , Novati Paolo 
Published: April 2022

AbstractIn this paper we are interested in the approximation of fractional powers of self-adjoint positive operators. Starting from the integral representation of the operators, we apply the trapezoidal rule combined with a double-exponential transform of the integrand function. In this work we show how to improve the existing error estimates for the scalar case and also extend the analysis to operators. We report some numerical experiments to show the reliability of the estimates obtained.
Lipschitzness is all you need to tame off-policy generative adversarial imitation learning
Authors: Blondé Lionel , Strasser Pablo , Kalousis Alexandros 
Published: April 2022

AbstractDespite the recent success of reinforcement learning in various domains, these approaches remain, for the most part, deterringly sensitive to hyper-parameters and are often riddled with essential engineering feats allowing their success. We consider the case of off-policy generative adversarial imitation learning, and perform an in-depth review, qualitative and quantitative, of the method. We show that forcing the learned reward function to be local Lipschitz-continuous is asine qua noncondition for the method to perform well. We then study the effects of this necessary condition and provide several theoretical results involving the local Lipschitzness of the state-value function. We complement these guarantees with empirical evidence attesting to the strong positive effect that the consistent satisfaction of the Lipschitzness constraint on the reward has on imitation performance. Finally, we tackle a generic pessimistic reward preconditioning add-on spawning a large class of reward shaping methods, which makes the base method it is plugged into provably more robust, as shown in several additional theoretical guarantees. We then discuss these through a fine-grained lens and share our insights. Crucially, the guarantees derived and reported in this work are valid foranyreward satisfying the Lipschitzness condition, nothing is specific to imitation. As such, these may be of independent interest.
BV analysis of Polyakov and Nambu–Goto theories with boundary
Authors: Martinoli S. , Schiavina M. 
Published: April 2022

AbstractThe Batalin–Vilkovisky data for Polyakov string theory on a manifold with (non-null) boundary are shown to induce compatible Batalin–Fradkin–Vilkovisky data, thus allowing BV-quantisation on manifolds with boundary. On the other hand, the analogous formulation of Nambu–Goto string theory fails to satisfy the needed regularity requirements. As a by-product, a concise description is given of the reduced phase spaces of both models and their relation, for any target d-dimensional Lorentzian manifold.
Anime-to-real clothing: Cosplay costume generation via image-to-image translation
Authors: Tango Koya , Katsurai Marie , Maki Hayato , Goto Ryosuke 
Published: April 2022

AbstractCosplay has grown from its origins at fan conventions into a billion-dollar global dress phenomenon. To facilitate the imagination and reinterpretation of animated images as real garments, this paper presents an automatic costume-image generation method based on image-to-image translation. Cosplay items can be significantly diverse in their styles and shapes, and conventional methods cannot be directly applied to the wide variety of clothing images that are the focus of this study. To solve this problem, our method starts by collecting and preprocessing web images to prepare a cleaned, paired dataset of the anime and real domains. Then, we present a novel architecture for generative adversarial networks (GANs) to facilitate high-quality cosplay image generation. Our GAN consists of several effective techniques to bridge the two domains and improve both the global and local consistency of generated images. Experiments demonstrated that, with quantitative evaluation metrics, the proposed GAN performs better and produces more realistic images than conventional methods. Our codes and pretrained model are available on the web.
Restoring geomorphic integrity in urban streams via mechanistically-based storm water management: minimizing excess sediment transport capacity
Authors: Hawley Robert J. , Russell Kathryn , Taniguchi-Quan Kristine 
Published: April 2022

AbstractStream channel erosion, enlargement, and habitat degradation are ubiquitous in urban watersheds with conventional stormwater management that increase channel-eroding flows relative to undeveloped watersheds. Hydrologic-based restoration aims to discharge a more natural flow regime via stormwater management interventions. Whether such interventions facilitate geomorphic recovery depends, in part, on the degree to which they restrict discharges that would otherwise contribute to channel erosion. Erosion potential (E), the ratio of post-developed to predeveloped sediment transport capacity, provides a simplified, mechanistic framework to quantify the relative influence of stormwater interventions on the geomorphic effectiveness of the flow regime. This paper compiles ca. five years of data following stormwater-based interventions in three distinct settings in the United States and Australia to demonstrate how the E framework can elucidate the role of hydrologic restoration interventions in facilitating trajectories of geomorphic recovery (or lack thereof). In a previously developed watershed with unstable streams, substantial reductions in E in one stream coincided with a trajectory of geomorphic recovery, whereas the control stream without E-reducing interventions exhibited continued instability. Furthermore, a stream downstream of a greenfield development that optimized their stormwater control measures to match the sediment transport capacity of the predeveloped regime (E = 1) was able to maintain a recovery trajectory in a legacy-impacted setting that is otherwise highly susceptible to hydromodification. Streambed material size, channel evolution stage, and the hydrogeomorphic setting also likely affect the level of E reduction necessary to promote geomorphic recovery, with coarser-grained and over-widened streams potentially needing less reduction than finer-grained and more entrenched channels. Although available space and funding will limit the ability to fully reduce E in previously developed watersheds, these case studies underscore the value of using stormwater control measures to maximize reductions in E if geomorphic stability is a goal of stormwater interventions.