bluuebunny/crossref_metadata_2025_split huggingface dataset:
Memristor‐based disturbance rejection control for port‐Hamiltonian systems with locally fixed‐time convergence
Authors: Liu Xinggui , Zhao Mei 
Published: May 2022

AbstractThe memristor is added to the port‐Hamiltonian systems to improve the disturbance suppression performance in this paper. The concepts of locally fixed‐time stability and locally fixed‐time control of port‐Hamiltonian systems are presented. From this starting point, two novel memristor‐based locally fixed‐time controllers are designed to suppress the external disturbance of port‐Hamiltonian systems via the interconnection and damping assignment passivity‐based control technique. Comparing with the classical interconnection and damping assignment passivity‐based control methodology without memristor, there are some advantages. First, the settling‐time related to the memristor‐based controllers in stabilizing the same port‐Hamiltonian systems are shorter. Second, the memristor‐based controllers can make the oscillation in the case of the strong periodic disturbance be better suppressed. Theoretical analysis shows that the memristor‐based controller possesses good disturbance rejection performance owing to it can make the system states in a neighbourhood accelerate convergence to the desired equilibrium point. Two illustrative examples show that the theoretical results and the controllers designed in this paper work very well.
Scene classification for remote sensing images with self‐attention augmented CNN
Authors: Liu Zongyin , Dong Anming , Yu Jiguo , Han Yubing , Zhou You , Zhao Kai 
Published: May 2022

AbstractRemote sensing scene classification aims to automatically assign a specific semantic label to each image. It is challenging to classify remote sensing scene images due to the images' diversity and rich spatial information. Recently, convolutional neural networks have been widely used to overcome these difficulties, such as the famous Visual Geometry Group (VGG) network. However, the VGG network with local receptive fields cannot model the global information of remote sensing images well. It also needs a large number of parameters and floating point operations to achieve satisfactory accuracy. To overcome these challenges, we introduce the self‐attention mechanism to the VGG network. Specifically, we replace the last four convolutional layers in the VGG‐19 network with two cascaded self‐attention blocks, each consisting of two multi‐head self‐attention (MHSA) layers with the residual network structure. The new structure can simultaneously explore the local and global information from remote sensing scenes. Such improvements not only reduce model parameters but also improve the classification performance. The effectiveness of the proposed method is validated through experiments on four public data sets, i.e., NaSC‐TG2, WHU‐RS19, AID and EuroSAT.
Measuring precise radial velocities on individual spectral lines
Authors: Al Moulla K. , Dumusque X. , Cretignier M. , Zhao Y. , Valenti J. A. 
Published: May 2022

Context. To enable radial velocity (RV) precision on the order of ~0.1 m s−1 required for the detection of Earth-like exoplanets orbiting solar-type stars, the main obstacle lies in mitigating the impact of stellar activity.
Aims. This study investigates the dependence of derived RVs with respect to the formation temperature of spectral line segments.
Methods. Using spectral synthesis, we computed the stellar temperature below which 50% of the emergent flux originates for each observed wavelength point of unblended spectral lines. We then constructed RV time series for different temperature ranges using template matching.
Results. With HARPS-N solar data and HARPS α Cen B measurements, we demonstrate on time intervals of prominent stellar activity that the activity-induced RV signal has different amplitude and periodicity depending on the temperature range considered. We compare the solar measurements with simulated contributions from active surface regions seen in simultaneous images, and find that the suppression of convective motion is the dominant effect.
Conclusions. From a carefully selected set of spectral lines, we are able to measure the RV impact of stellar activity at various stellar temperatures ranges. We are able to strongly correlate the effect of convective suppression with spectral line segments formed in hotter temperature ranges. At cooler temperatures, the derived RVs exhibit oppositely directed variations compared to the average RV time series and stronger anticorrelations with chromospheric emission.
Detection of eccentric close-binary supermassive black holes with incomplete interferometric data
Authors: Kovačević Andjelka B. , Songsheng Yu-Yang , Wang Jian-Min , Popović Luka Č. 
Published: May 2022

Context.Recent studies have proposed that General Relativity Analysis via VLT InTerferometrY upgrade (GRAVITY+) on board the Very Large Telescope Interferometer (VLTI) is able to trace the circular orbit of the subparsec (≲0.1 pc) close-binary supermassive black holes (CB-SMBHs) by measuring the photo-centre variation of the hot dust emission. However, the CB-SMBHs orbit may become highly eccentric throughout the evolution of these objects, and the orbital period may be far longer than the observational time baseline.Aims.We investigate the problem of detecting the CB-SMBH with hot dust emission and high eccentricity (eCB-SMBH,e= 0.5) when the observed time baselines of their astrometric data and radial velocities are considerably shorter than the orbital period.Methods.The parameter space of the Keplerian model of theeCB-SMBH is large for exploratory purposes. We therefore applied the Bayesian method to fit orbital elements of theeCB-SMBH to combine radial velocity and astrometric data covering a small fraction of the orbital period.Results.We estimate that a number of potentialeCB-SMBH systems within reach of GRAVITY+ will be similar to the number of planned circular targets. We show that using observational time baselines that cover ≳10% of the orbit increases the possibility of determining the period, eccentricity, and total mass of aneCB-SMBH. When the observational time baseline becomes too short (~5%), the quality of the retrievedeCB-SMBH parameters degrades. We also illustrate how interferometry may be used to estimate the photo-centre at theeCB-SMBH emission line, which could be relevant for GRAVITY+ successors. Even if the astrometric signal foreCB-SMBH systems is reduced by a factor of√(1 - e2)compared to circular ones, we find that the hot dust emission ofeCB-SMBHs can be traced by GRAVITY+ at the elementary level.
The single supervisory mechanism and the European framework for the enforcement of competition law: a comparison between two models for economic governance in the EU
Authors: Annunziata Filippo , Maggiolino Mariateresa 
Published: May 2022

AbstractThis paper proposes to develop a parallel reading of the banking supervision system and the framework for the enforcement of competition law, with the purpose of setting out points of convergence and divergence between the two, analyzing their institutional architecture and various issues pertaining to the relevant, applicable law. This approach might prove fruitful for a better understanding of each of the two systems, and for filling the gaps left open and unresolved by legislative texts. It might also offer some contribution in view of a more general analysis of the key-issues that those who design the systems meant to govern the European economy should consider.
Dynamic mapping of cholera outbreak during the Yemeni Civil War, 2016–2019
Authors: Simpson Ryan B. , Babool Sofia , Tarnas Maia C. , Kaminski Paulina M. , Hartwick Meghan A. , Naumova Elena N. 
Published: May 2022

AbstractWidespread destruction from the Yemeni Civil War (2014–present) triggered the world’s largest cholera outbreak. We compiled a comprehensive health dataset and created dynamic maps to demonstrate spatiotemporal changes in cholera infections and war conflicts. We aligned and merged daily, weekly, and monthly epidemiological bulletins of confirmed cholera infections and daily conflict events and fatality records to create a dataset of weekly time series for Yemen at the governorate level (subnational regions administered by governors) from 4 January 2016 through 29 December 2019. We demonstrated the use of dynamic mapping for tracing the onset and spread of infection and manmade factors that amplify the outbreak. We report curated data and visualization techniques to further uncover associations between infectious disease outbreaks and risk factors and to better coordinate humanitarian aid and relief efforts during complex emergencies.
Photo-oxygenation of water media using photoactive plasmonic nanocomposites
Authors: Saratovskii A. S. , Senchik K. Yu. , Karavaeva A. V. , Evstropiev S. K. , Nikonorov N. V. 
Published: May 2022

Plasmonic nanocomposites ZnO–Ag and ZnO–SnO2–Ag(AgCl) were prepared by the polymer–salt method, and their structure and morphology were studied using XRD and SEM analyses. It was found that the addition of photoactive inorganic nanocomposites ZnO–Ag and ZnO–SnO2–Ag(AgCl) in pure water significantly enhances the effectiveness of its disinfection and purification during UV treatment and provides the effective water oxygenation. Oxygen photogeneration under blue light (λex. = 405 nm) can be related to the plasmon-excitation processes in ZnO–SnO2–Ag(AgCl) composites. Prepared composites demonstrate antibacterial activity against both Gram-positive and Gram-negative bacteria. The increase of Ag content in ZnO–Ag and ZnO–SnO2–Ag(AgCl) composites significantly enhances their antibacterial activity.
Yield, zinc efficiencies and biofortification of wheat with zinc sulfate application in soil and foliar nanozinc fertilisation
Authors: Jalal Arshad , Galindo Fernando Shintate , Freitas Leandro Alves , Oliveira Carlos Eduardo da Silva , Lima Bruno Horschut de , Pereira Íngrid Torres , Ferraz Graziela Franceschini , Souza Jeferson Silva de , Costa Kaway Nunes da , Nogueira Thiago Assis Rodrigues , Teixeira Filho Marcelo Carvalho Minhoto 
Published: May 2022

Context Agronomic biofortification of wheat (Triticum aestivum L.) with zinc (Zn) is an effective approach to increase grain Zn concentration and productivity and alleviate Zn malnutrition in humans. Foliar Zn application is an alternative strategy to endorse soil Zn deficiency with better grain Zn partitioning. Aims This study aimed to better understand dose management of soil and foliar Zn application in wheat for biofortification. Methods The objectives was to evaluate the effect of foliar applied nano Zn doses (0, 0.75, 1.5, 3 and 6 kg/ha (zinc oxide, ZnO) 50% at tillering and 50% at grain filling in combination) with soil Zn application (0 and 8 kg/ha, as zinc sulfate) on growth, nutrition, Zn use efficiencies, intake and yield biofortification of wheat in 2019 and 2020 under Brazilian savanna. Key results Combined foliar and soil Zn application increased shoot and grains Zn concentration and accumulation with greater dry matter (9.8 and 10.6%) and grain yield (9.8 and 11%) of wheat as compared to control in 2019 and 2020 respectively. Zinc use efficiency (ZnUE), Zn utilisation efficiency and applied Zn recovery improved with soil Zn application and 2.5 kg/ha foliar nano Zn, but decreased with further increase in foliar Zn application. Zn sulfate stood out for increasing crop productivity while foliar spray with nano Zn for better grains biofortification of wheat. Conclusions Soil Zn application along with 3 kg/ha of foliar nano Zn increased plant and grains Zn concentration and accumulation, dry matter, grain yield, Zn partitioning index and Zn intake in wheat in tropical conditions of Brazil. Implications The combined application of soil and foliar Zn in harsh tropical savannah condition could better improve Zn nutrition, crop growth, and productivity with better Zn biofortification and intake of wheat.
Evaluation of performance and stability of new sources for tolerance to post-emergence herbicides in lentil (
Authors: Balech Rind , Maalouf Fouad , Patil Somanagouda B. , Hejjaoui Kamal , Abou Khater Lynn , Rajendran Karthika , Rubiales Diego , Kumar Shiv 
Published: May 2022

Context Yield losses in lentil (Lens culinaris ssp. culinaris Medik.) caused by weeds are estimated at 20–80%. In the absence of effective broad-spectrum herbicides, the menace of weed has emerged as a serious yield constraint in lentil. Aims Identification of tolerance to two broad-spectrum post-emergence herbicides, imazethapyr and metribuzin. Methods 221 lentil accessions were screened at the experimental research station of the International Center for Agricultural Research in the Dry Areas, Terbol (Lebanon) over four crop seasons (2014/15–2018/19). During the 2014/15 season, a preliminary screening experiment was conducted with 221 lentil accessions in an alpha lattice design with two replications, where accessions were treated at the pre-flowering stage at 150% of the recommended dose of imazethapyr (112.5 g active ingredient/ha) or metribuzin (315 g active ingredient/ha). Based on the preliminary results, 38 accessions were selected for further evaluation. In subsequent testing, the selected accessions were screened at 100% and 150% of the recommended doses of imazethapyr or metribuzin. Key results Herbicide treatments delayed the flowering time and maturation of tested lentil accessions. The plant height of selected tolerant accessions was reduced by 15% and 8% in the plots treated by imazethapyr and metribuzin, respectively. Reduction index (RIsy) was an effective tool to select for herbicide tolerance. Stability analysis indicated that two accessions (IG4400 and IG5722) performed under high rainfall environments while two other accessions (IG323 and IG4605) were adapted to low rainfall environments. Conclusions Four accessions (IG323, IG5722, IG4400, IG4605) were identified as independently tolerant to metribuzin and imazethapyr. Implications The identified herbicide-tolerant accessions can be used to develop herbicide-tolerant cultivars.
Use words, not constructions!
Authors: Proisl Thomas 
Published: May 2022

AbstractThe aim of collostructional analysis or, more precisely, simple collexeme analysis, is to quantify the statistical association between a constructioncand a lexemelthat occurs in a particular slot of the construction. The analysis is based on2×2contingency tables that ought to represent a cross-classification of the units of analysis. So far, the units of analysis have been identified either as all constructions in the corpus or all instances of a classCof constructions to which constructioncbelongs. In practice, it is often not possible or feasible to identify these constructions. Therefore, the sample size is typically approximated by heuristic estimates. The bottom-right cell of the contingency table is most affected by these approximations. I suggest that the units of analysis be defined on the word level, instead, as the classWof word forms that satisfy the restrictions on the collexeme slot ofc.
Sustainable development matters for animals too: Governments have a responsibility to recognize that
Authors: Sebo Jeff , Verkuijl Cleo , José Hötzel Maria , Ploy Ploy , Bastos Lima Mairon , Green Jonathan 
Published: May 2022

Abstract
Animals matter for sustainable development, and sustainable development matters for animals. Yet animal welfare remains largely neglected in sustainable development governance. The 2030 Agenda for Sustainable Development aims to protect species, biodiversity, and habitats, but not individual animals. This June, governments will convene for the UN Stockholm+50 Conference, which marks 50 years of international environmental decision making. At this conference, governments have an opportunity to recognize the importance of animal welfare for sustainable development, and to aspire to harm animals less and benefit them more as part of sustainable development governance. We call on governments to take these steps for the sake of human and non-human animals alike.
L(1, d)-labeling number of direct product of two cycles
Authors: Wu Qiong , Shiu Wai Chee 
Published: May 2022

For positive number d, an L(1, d) -labeling f of G is an assignment of numbers to vertices of G such that |f(u) - f(v)| ≥ 1 if d(u, v) = 1, and |f(u) - f(v)| ≥ d if d(u, v) = 2. Then the span of f is the difference between the maximum and the minimum numbers assigned by f. The L(1, d) -labeling number of G, denoted by λ1,d (G), is the minimum span over all L(1, d) -labelings of G. In this paper, the authors give the L(1, d) -labeling numbers of the direct product of two cycles Cm and Cn for d ≥ 2 for some values of m and n. Some cases for 1 ≤ d <2 are also discussed.
Structure of skew cyclic codes over
Authors: Islam Habibul , Prakash Om 
Published: May 2022

In this paper, for any integer k > 1, we study skew cyclic codes of length n over , where uk = 0 and p is an odd prime. It is noted that the ring Rk is isomorphic to the quotient ring . We characterize skew cyclic codes of length n over Rk as free left Rk[x;θ] -submodules of Rk[x;θ]/〈xn - 1〉 and construct their generators and minimal generating sets. Also, an algorithm of encoding and decoding of these codes has been provided. Finally, some examples of optimal linear codes are given from Gray images of skew cyclic codes over Rk.
Three-dimensional mathematical modelling and dynamic analysis of freestanding triboelectric nanogenerators
Authors: Guo Xin , Shao Jiajia , Willatzen Morten , Yang Yi , Wang Zhong Lin 
Published: May 2022

Abstract
Energy harvesting system based on triboelectric nanogenerators (TENGs) has aroused wide interest from many researchers since it integrates multiple disciplines together including electromagnetics, electric circuit theory, materials science and mechanical engineering. Accurate modeling of a TENG is an indispensable part for revealing the relationships and interactions among physical quantities from different areas. Here, a three-dimensional mathematical model of a contact-mode freestanding TENGs (CF-TENGs) is built with a combination of physical abstraction and geometry configuration, which makes it possible to dynamically analyze the variations of the field and circuit quantities. An accurate Norton’s equivalent circuit model that consists of a current source in parallel with a pure capacitive reactance is proposed. Based on this model the reason for identifying the displacement current as the driving force of TENGs is elucidated, and quantitatively determine the current flowing through the external load resistor and the internal equivalent capacitor. More importantly, a universal dynamic simulation model consisting of a quasi-electrostatic model and a circuit model for the TENG-based energy harvesting system is presented. The presented composite model exhibits an obvious advantage in terms of revealing the dynamic output of TENGs with arbitrary geometry and charge distribution. Finally, based on the characteristics of linearity and time-invariance of the CF-TENG, general optimization strategies are pinpointed, which allow us to accurately predict the maximum output efficiency (close to 82.5%).
An improved Liouville type theorem for Beltrami flows
Authors: Wang Na , Zhang Zhibing 
Published: May 2022

Abstract
In this note, we improved the Liouville type theorem for the Beltrami flows. Two different methods are used to prove it, one is the monotonicity method, and another is proof by contradiction. The conditions that we proposed on Beltrami flows are significantly weaker than previously known conditions.
Stray neutron radiation exposures from proton therapy: physics-based analytical models of neutron spectral fluence, kerma and absorbed dose
Authors: Shrestha Suman , Newhauser Wayne D , Donahue William P , Pérez-Andújar Angélica 
Published: May 2022

Abstract

Objective. Patients who receive proton beam therapy are exposed to unwanted stray neutrons. Stray radiations increase the risk of late effects in normal tissues, such as second cancers and cataracts, and may cause implanted devices such as pacemakers to malfunction. Compared to therapeutic beams, little attention has been paid to modeling stray neutron exposures. In the past decade, substantial progress was made to develop semiempirical models of stray neutron dose equivalent, but models to routinely calculate neutron absorbed dose and kerma are still lacking. The objective of this work was to develop a new physics based analytical model to calculate neutron spectral fluence, kerma, and absorbed dose in a water phantom. Approach. We developed the model using dosimetric data from Monte Carlo simulations and neutron kerma coefficients from the literature. The model explicitly considers the production, divergence, scattering, and attenuation of neutrons. Neutron production was modeled for 120–250 MeV proton beams impinging on a variety of materials. Fluence, kerma and dose calculations were performed in a 30 × 180 × 44 cm3 phantom at points up to 43 cm in depth and 80 cm laterally. Main Results. Predictions of the analytical model agreed reasonably with corresponding values from Monte Carlo simulations, with a mean difference in average energy deposited of 20%, average kerma coefficient of 21%, and absorbed dose to water of 49%. Significance. The analytical model is simple to implement and use, requires less configuration data that previously reported models, and is computationally fast. This model appears potentially suitable for integration in treatment planning system, which would enable risk calculations in prospective and retrospective cases, providing a powerful tool for epidemiological studies and clinical trials.
Effects of plasma boundary shape on the βN
threshold in the suppression of tearing mode in toroidal tokamak plasmas with reversed magnetic shear
Authors: Wang H Y , Liu T , Liu Y Q , Wang Z X 
Published: May 2022

Abstract
The toroidal magnetohydrodynamic code MARS-F (Liu et al 2000 Phys. Plasmas
7 3681) is adopted to investigate the plasma boundary shape effect on the

β
N

threshold (

β
N

is the normalized plasma pressure) reported in (Liu et al 2017 Plasma Phys. Control. Fusion
59 065009) in reversed magnetic shear toroidal tokamak plasmas under different separations

Δ

r
s

between the two rational surfaces of the same helicity. The boundary shape effect is modeled via elongation

κ

and triangularity

δ

. Here, the study focuses on

n
=
1

cases (

n

is the toroidal mode number). In the small

Δ

r
s

regime, the critical value

β

N
c

increases as

κ

increases (without triangularity), and barely changes with triangularity (at small elongation). On the other hand, at large elongation (e.g.

κ

=
2

), the critical value of

β

N
c

decreases with increasing

δ

. The change in the

β

N
c

may be due to a change in the coupling strength between different poloidal harmonics, due to the fact that, besides

m
=
±
1

toroidal coupling (

m

is the poloidal mode number), a large elongation

κ

(or triangularity

δ

) can result in the

m
=
2

(

m
=
3

) equilibrium component and thus enhances the coupling between the

m

and

m
=
±
2

(

m
=
±
3

). In the large

Δ

r
s

regime, with increasing

κ

(without triangularity),

β

N
c

first slightly increases followed by a quick reduction. Moreover, as

δ

increases, the critical value

β

N
c

decreases at small elongation, and first increases followed by a decrease at large elongation (e.g.

κ
=
2

). Besides the change in the coupling strength between different poloidal harmonics, the change in the

β

N
c

in the large

Δ

r
s

regime is also related to the mode transition. The corresponding physics mechanisms underlying the shift of

β

N
c

due to the plasma boundary shape are all discussed in detail.