Wide Domain Research Articles

Correcting Hargreaves‐Samani formula using geographical coordinates and rainfall over different timescales

AbstractThe United Nations Food and Agricultural Organization (FAO) approved the Hargreaves‐Samani formula (HAR‐85) as an alternative to the standard Penman‐Monteith method (FAO‐PM) for estimating grass reference evapotranspiration (ETo). With much less data demand, HAR‐85 is unequivocally useful where meteorological variables are often scarce, incomplete or unavailable. Herein, we evaluate HAR‐85 against FAO‐PM across 2.505 million km2, representing Sudan and South Sudan and encompassing wide hydroclimate domains including the Nile River. We further propose simple year‐round and seasonal adjustment models to correcting HAR‐85 across the entire study area. The models express HAR‐85's error in multiple linear regressions in terms of latitude, longitude, altitude and/or monthly rainfall. Varying data periods, including odd, even and all years, are used in the evaluation and the adjustment models development and validation processes to investigate the influence of changing data period. A suit of eight performance indicators shows dependency of the original bias of HAR‐85 on the geographical location, monthly rainfall amount, season of the year and data period. All error indicators amplify southward from the hyper‐arid region to the dry sub‐humid zone. For example, the mean bias error (MBE) ranges from −0.51 to 1.29 mm/day, respectively. Study area‐wide, HAR‐85 least represents FAO‐PM during the hottest month and the transitional month (between the wet and dry‐cool seasons) with MBE of 0.65 and 0.70 mm/day, respectively. Conversely, it represents FAO‐PM the most in the wettest month, with smallest MBE of 0.32 mm/day. Beholding this spatiotemporal trait, the final yearly and seasonal adjustment models developed herein enormously moderate the predominant overestimation of the original HAR‐85. The former model explains 46.7% of the error variance whereas 36.9% to 62.3% of the variation in the error is explainable by the latter models. These adjustment models narrow the monthly MBE among the stations from −0.71‐2.17 to −0.80‐1.20 and −0.65‐0.99 mm/day, respectively. Without undermining the accuracy, the year‐round adjustment model can still be feasibly recommended for general use across the study area.

Analysis of Additional Damping Control Strategy and Parameter Optimization for Improving Small Signal Stability of VSC-HVDC System

The voltage source converter based high voltage direct current (VSC-HVDC) system is based on voltage source converter, and its control system is more complex. Also affected by the fast control of power electronics, oscillation phenomenon in wide frequency domain may occur. To address the problem of small signal stability of the VSC-HVDC system, a converter control strategy is designed to improve its small signal stability, and the risk of system oscillation is reduced by attaching a damping controller and optimizing the control parameters. Based on the modeling of the VSC-HVDC system, the general architecture of the inner and outer loop control of the VSC-HVDC converter is established; and the damping controllers for DC control and AC control are designed in the phase-locked loop and the inner and outer loop control parts respectively; the state-space state model of the control system is established to analyze its performance. And the electromagnetic transient simulation model is built on the PSCAD/EMTDC simulation platform to verify the accuracy of the small signal model. The influence of the parameters of each control part on the stability of the system is summarized. The main control parts affecting stability are optimized for the phenomenon of oscillation due to changes in operation mode occurring on the AC side due to faults and other reasons, which effectively eliminates system oscillation and improves system small signal stability, providing a certain reference for engineering design.

Propagation characteristics of longitudinal modes in dusty plasmas

The space-time correlation function has been obtained in strongly coupled dusty plasmas (SCDPs) using equilibrium molecular dynamics (EMD) simulations. The simulated results for three-dimensional (3D) SCDPs with suitable normalization are computed over a wide domain of plasma parameters (Γ, κ) in a microcanonical ensemble. The EMD simulations indicate that different modes of propagated wave in SCDPs are analyzed for four different values of wave number (k). New investigations of normalized longitudinal current correlation function CL(k, t) show that the amplitude of oscillation and frequency of propagated modes increase with an increase in k. The obtained results for longitudinal modes of oscillation indicate that the dust particles remain in damping behavior at the low Γ, damped oscillation with decreasing amplitude inside decaying exponential envelope at intermediate Г, and sinusoidal oscillation at high Г, depending on κ. The system size (N) does not significantly affect the propagated modes of oscillation, while the periodic oscillation shifts toward higher Γ with increasing N and κ. The computations show that normalized longitudinal CL(k, t) current correlation particularly depend on Coulomb coupling (Γ), Debye screening (κ), and wave number (k). In our simulations, the frequency and the amplitude of oscillation of the dust particles decrease with an increment of κ and system size (N), but the frequency increases and the amplitude decreases with increasing Γ, as expected. It has been demonstrated that the EMD method is used to study the different propagated modes in dusty plasma systems and can be used to predict the damping behavior, damped oscillation, and periodic phenomena in 3D strongly coupled SCDPs.

Examining the Threat of ChatGPT to the Validity of Short Answer Assessments in an Undergraduate Medical Program.

ChatGPT is an artificial intelligence model that can interpret free-text prompts and return detailed, human-like responses across a wide domain of subjects. This study evaluated the extent of the threat posed by ChatGPT to the validity of short-answer assessment problems used to examine pre-clerkship medical students in our undergraduate medical education program. Forty problems used in prior student assessments were retrieved and stratified by levels of Bloom's Taxonomy. Thirty of these problems were submitted to ChatGPT-3.5. For the remaining 10 problems, we retrieved past minimally passing student responses. Six tutors graded each of the 40 responses. Comparison of performance between student-generated and ChatGPT-generated answers aggregated as a whole and grouped by Bloom's levels of cognitive reasoning, was done using t-tests, ANOVA, Cronbach's alpha, and Cohen's d. Scores for ChatGPT-generated responses were also compared to historical class average performance. ChatGPT-generated responses received a mean score of 3.29 out of 5 (n = 30, 95% CI 2.93-3.65) compared to 2.38 for a group of students meeting minimum passing marks (n = 10, 95% CI 1.94-2.82), representing higher performance (P = .008, η2 = 0.169), but was outperformed by historical class average scores on the same 30 problems (mean 3.67, P = .018) when including all past responses regardless of student performance level. There was no statistically significant trend in performance across domains of Bloom's Taxonomy. While ChatGPT was able to pass short answer assessment problems spanning the pre-clerkship curriculum, it outperformed only underperforming students. We remark that tutors in several cases were convinced that ChatGPT-produced responses were produced by students. Risks to assessment validity include uncertainty in identifying struggling students and inability to intervene in a timely manner. The performance of ChatGPT on problems requiring increasing demands of cognitive reasoning warrants further research.

Mental health outcome in hospitalized COVID-19 patients: An observational analysis from North Indian tertiary care hospital

AimThe study investigate the severity of perceived stress and wide domains of psychiatric symptoms reported on initial screening in hospitalized patients of COVID-19 with a second aim to determine the role of sociodemographic factors and coping styles in the hospitalized patients of COVID-19. MethodTotal 224 patients of COVID-19 infection, hospitalized in various isolation facilities were assessed via web-based self-reported questionnaires on perceived stress scale, brief cope inventory, and DSM-5 crosscutting level-1 questionnaire. ResultsMajority of the patients reported moderate level of stress followed by mild and severe. Depression and Anxiety symptoms were most common psychopathologies though the patients have reported greater severity in various domains of psychiatric symptoms. Coping styles explains most of variance (64.8%) of the perceived stress. Similarly total PSS scores, coping styles, COVID-19 status and sociodemographic factors contributed significantly to the variance of all psychiatric symptoms. ConclusionFactors like female gender, being married, belonging to nuclear families, service class and urban domicile are the significant factors determining higher risk of stress and developing more psychopathologies. Furthermore, coping styles used by the patients have a greater moderating effect on mental health symptoms and their perceived stress which can be a major area for interventions to reduce the mental health morbidities.

Effect of annealing treatment on the magnetic properties with wide temperature range of Co-doped FeSi soft magnetic composites

Fe-Si-Co soft magnetic composites (SMCs) coated with silicone resin were successfully prepared in this work. The influences of annealing treatment on the temperature/frequency-dependent behaviors of magnetic properties for SMCs were studied by microstructureanalysis and loss separation. Results show that the core loss of Fe-6.5Si-1.0Co SMCs gradually decreases with annealing temperatures rising from 500 °C to 700 °C when measured at 50 kHz, while the core loss of Fe-6.5Si-3.0Co SMCs first decreases then increases. Meanwhile, the effective permeability Fe-6.5Si-1.0Co and Fe-6.5Si-3.0Co SMCs are significantly improved. Simultaneous optimization for core loss and effective permeability benefits from the residual stress relief and defect elimination induced by annealing. Fe-6.5Si-1.0Co SMCs annealed at 700 °C shows excellent comprehensiveperformances with core loss of 766.7 mW/cm3 and effective permeability of 112.3 measured at 0.1 T / 50 kHz. While annealing at excessive temperature causes the phase transition and change in resistance of silicone-resin coatings, leading to the rapid deterioration of the magnetic performances. As for the temperature characteristics, the Fe-Si-1.0Co SMCs also exhibits good stability for effective permeability and negative correlation for core loss with the measuring temperature ranging from −25 °C to 125 °C. This work may provide some theoretical support for the wide temperature domain application of the Co-doped FeSi SMCs.

Data- and theory-guided learning of partial differential equations using SimultaNeous basis function Approximation and Parameter Estimation (SNAPE)

Full-field discrete measurements of the continuous spatiotemporal response of physical processes often generate large datasets. Such continuous spatiotemporal dynamic models are represented by partial differential equations (PDEs). In the past, attempts have been made to identify the PDE models from the measured response by inferring its parameters via regression or deep learning-based techniques. But the previously presented regression-based methods fail to estimate the parameters of the higher-order PDE models in the presence of moderate noise. Likewise, the deep learning-based methods lack the much-needed property of repeatability and robustness in the identification of PDE models from the measured response. The proposed method of SimultaNeous Basis Function Approximation and Parameter Estimation (SNAPE) addresses such drawbacks by simultaneously fitting basis functions to the measured response and estimating the parameters of both ordinary and partial differential equations. The domain knowledge of the general multidimensional process is used as a constraint in the formulation of the optimization framework. The alternating direction method of multipliers (ADMM) algorithm is used to simultaneously optimize the loss function over the parameter space of the PDE model and coefficient space of the basis functions. The proposed method not only infers the parameters but also estimates a continuous function that approximates the solution to the PDE model. SNAPE not only demonstrates its applicability on various complex dynamic systems that encompass wide scientific domains including Schrödinger equation, chaotic duffing oscillator, and Navier–Stokes equation but also estimates an analytical approximation to the process response. The method systematically combines the knowledge of well-established scientific theories and the concepts of data science to infer the properties of the process from the observed data.

On a strengthening of the Blaschke–Leichtweiss theorem

The Blaschke–Leichtweiss theorem (Leichtweiss in Abh Math Semin Univ Hambg 75:257–284, 2005) states that the smallest area convex domain of constant width w in the 2-dimensional spherical space \({\mathbb {S}}^2\) is the spherical Reuleaux triangle for all \(0<w\le \frac{\pi }{2}\). In this paper we extend this result to the family of wide r-disk domains of \({\mathbb {S}}^2\), where \(0<r\le \frac{\pi }{2}\). Here a wide r-disk domain is an intersection of spherical disks of radius r with centers contained in their intersection. This gives a new and elementary proof of the Blaschke–Leichtweiss theorem. Furthermore, we investigate the higher dimensional analogue of wide r-disk domains called wide r-ball bodies. In particular, we determine their minimum spherical width (resp., inradius) in the spherical d-space \({\mathbb {S}}^d\) for all \(d\ge 2\). Also, it is shown that any minimum volume wide r-ball body is of constant width r in \({\mathbb {S}}^d\), \(d\ge 2\).

Effect of Different Anti-Stripping Agents on the Rheological Properties of Asphalt

Water damage is one of the main forms of early damage of highway asphalt pavement, which seriously affects the service performance of asphalt pavement. To address the problem of early water damage of asphalt pavement, the addition of anti-stripping agents in asphalt is an effective technical means. To further analyze the influence of anti-stripping agents on asphalt performance, Qingchuan rock asphalt, acylamine anti-stripping agent, fatty amine anti-stripping agent, rock asphalt + acylamine anti-stripping agent and rock asphalt + fatty amine anti-stripping agent were selected to modify the base asphalt. The rheological properties of modified asphalt were tested using a dynamic shear rheometer and bending beam rheometer. Combined with the mathematical-model-fitting test results of Sigmoidal, Burgers, viscoelastic continuum damage model (VECD), etc., the effects of different anti-stripping agents on the rheological properties of asphalt were evaluated through model parameters. The results showed that the Qingchuan rock asphalt could improve the high-temperature resistance to deformation of asphalt and improved the resistance to deformation of asphalt in a wide frequency domain but increased the risk of low-temperature cracking of asphalt. Acylamine anti-stripping agents and aliphatic amine anti-stripping agents reduced the elastic recovery ability and deformation resistance under a wide frequency domain of asphalt at high temperatures but enhanced the flexible deformation and ductility of asphalt at low temperatures. The compound anti-stripping agent not only improved the high-temperature deformation resistance of asphalt, but also improved the deficiency of rock asphalt’s low-temperature performance and effectively enhanced its performance.

Battery degradation diagnosis with field data, impedance-based modeling and artificial intelligence

• Electrode-level degradation diagnosis approach for lithium-ion batteries • Hybrid model integrates the battery impedance and OCV-reconstruction • Accurate parameter identification with artificial intelligence and field data • Accurate estimation of capacity fade, power fade, and degradation modes • Robustness analysis and data requirements analysis for cloud applications By collecting battery data from the field and building up the battery digital twin in the cloud, the degradation of batteries can be monitored online on the electrode level and the information regarding the degradation modes can be extracted from the data. Here, we present a degradation diagnosis framework for lithium-ion batteries by integrating field data, impedance-based modeling, and artificial intelligence, revolutionizing the degradation identification with accurate and robust estimation of both capacity and power fade together with degradation mode analysis. By integrating an impedance-based model and an open-circuit voltage reconstruction model, the hybrid model consists of parameters representing the change of impedance in a wide frequency domain and the change of open-circuit voltage during degradation. Based on the field data with low and high dynamics, the data-driven parameter identification method using a multi-step cuckoo search algorithm considering parameter sensitivity differences shows high accuracy and robustness in aging parameter estimation and degradation mode identification even under sensor noise. Furthermore, the data requirement for the battery digital twin in the sense of sampling rate was investigated considering degradation identification accuracy, computational cost, and data storage cost. This work highlights the opportunity in online electrode-level degradation diagnosis in the field through battery modeling and artificial intelligence.

Nanoarchitectonics of MnO2 nanotubes as sea urchin-like aggregates for dielectric response and microwave absorption with a wide concentration domain

Nanoarchitectonics of MnO2 nanotubes as sea urchin-like aggregates for dielectric response and microwave absorption with a wide concentration domain

Silane‐Mediated Expansion of Domains in Si‐Doped κ‐Ga2O3 Epitaxy and its Impact on the In‐Plane Electronic Conduction

AbstractUnintentionally doped (001)‐oriented orthorhombic κ‐Ga2O3 epitaxial films on c‐plane sapphire substrates are characterized by the presence of ≈ 10 nm wide columnar rotational domains that can severely inhibit in‐plane electronic conduction. Comparing the in‐ and out‐of‐plane resistance on well‐defined sample geometries, it is experimentally proved that the in‐plane resistivity is at least ten times higher than the out‐of‐plane one. The introduction of silane during metal‐organic vapor phase epitaxial growth not only allows for n‐type Si extrinsic doping, but also results in the increase of more than one order of magnitude in the domain size (up to ≈ 300 nm) and mobility (highest µ ≈ 10 cm2V−1s−1, with corresponding lowest ρ ≈ 0.2 Ωcm). To qualitatively compare the mean domain dimension in κ‐Ga2O3 epitaxial films, non‐destructive experimental procedures are provided based on X‐ray diffraction and Raman spectroscopy. The results of this study pave the way to significantly improved in‐plane conduction in κ‐Ga2O3 and its possible breakthrough in new generation electronics. The set of cross‐linked experimental techniques and corresponding interpretation here proposed can apply to a wide range of material systems that suffer/benefit from domain‐related functional properties.

A Composite Variable Structure PI Controller for Sensorless Speed Control Systems of IPMSM

In the speed control system of an Interior Permanent Magnet Synchronous Motor (IPMSM) without a speed sensor, PI controllers using only a fixed set of parameters cannot achieve accurate tracking of the estimated speed in a wide speed domain and also suffer from step response overshoot. This paper proposes a Compound Variable Structure PI (CVSPI) controller to improve the system control performance. It can choose whether to include an integral term according to the size of the system deviation to speed up the response. It also introduces a Model Reference Adaptive System (MRAS) speed observer in the controller to estimate the speed and adaptively adjust the size of the anti-integration saturation gain to improve the dynamic response following performance and immunity of the system. A feed-forward link is added for a given input differential to achieve an accurate answer to time-varying inputs. As the linear compensation matrix of the conventional MRAS is a unit matrix, the speed can only be accurately observed in a specific speed range. In this paper, a new linear compensation matrix is designed, and a new speed adaptive law is derived, allowing the improved MRAS to measure speed over a wide range accurately. Simulation results validate the excellent control performance of the CVSPI and the accuracy of the enhanced MRAS over a wide speed range.

Intervention research in health promotion: policy issues, the example of the ten-year cancer strategy in France

Abstract Prevention research covers a wide domain of studies, including identification of unknown risk factors for certain cancers, for example prostate cancer; or health promotion with approaches by population, by living environment or by territory. This research focuses in particular on identified carcinogenic factors (e.g. tobacco, alcohol, certain pesticides) but also on the causes of the prevalence of these factors in certain populations. PHIR makes it possible to meet these challenges. In 2010, the French National Cancer Institute was a pioneer in the development of PHIR in France and decided in 2021 to make it one of the spearheads of its ten-year strategy. This presentation will aim to give an account of this policy of developing RISP as a relevant tool for thinking about health promotion policies and actions, by targeting the issue of inequalities as one of the priority research objects as well as certain audiences (young people, vulnerable populations). The presentation will discuss four challenges for the implementation of this research policy: the development of the French scientific community in order to be able to respond to priority issues; the structuring and animation of this community; the evaluation of research projects and the mobilisation of a still timid global community; the articulation of academic and concrete/experiential knowledge. Through a concrete example of a national research development policy, the aim of this presentation is to help participants understand the challenges of RISP (its obstacles and levers, not limited to financial issues), the organisation of research, and the links between the actors involved (researchers and field workers, beneficiaries, health professionals). The first part will focus on identifying the participants’ representations of the obstacles to the development of RISP. The second part will be an interactive presentation of 12 minutes, the last 2-3 minutes will be devoted to final questions.

Collaborative Defense-GAN for protecting adversarial attacks on classification system

With rapid progress and significant successes in a wide domain of applications, deep learning has been extensively employed for solving complex problems. However, performance of deep learning has been vulnerable to well-designed samples, called adversarial samples. These samples are carefully designed to deceive the deep learning models without human perception. Therefore, vulnerability to adversarial attacks becomes one of the major concerns in life-critical applications of deep learning. In this paper, a novel approach to counter adversarial samples is proposed to strengthen the robustness of a deep learning model. The strategy is to filter the perturbation noise in adversarial samples prior to prediction. The proposed defense framework is based on DiscoGANs to discover the relation between attacker and defender characteristics. Attacker models are created to generate the adversarial samples from the training data, while the defender model is trained to reconstruct original samples from the adversarial samples. These two frameworks are trained to compete with each other in an alternating manner. The experimental results on different attack models are compared with popular defense mechanisms on three benchmark datasets. Our proposed method shows promising results and can improve the robustness on both white-box and black-box attacks including the computation time.

Experimental research on the stability margin of a variable geometry scramjet combustor in wide flight conditions

In this paper, aiming at the situation that when fixed geometry combustors are operating for extended periods under off-design performance characterization conditions, the high thrust cannot be provided during acceleration, a variable geometry scramjet combustor is designed and studied. The experimental study was carried out by the method of interval matching under the combined flight conditions of Mach 2.0/4.0/6.0 and equivalence ratios of 0.6/0.8/1.0/1.2. In this process, the ability of the variable geometry combustor that could continuously regulate the expansion ratio from 1.4 to 3.4 was used for optimum performance. The performance could be effectively optimized by matching the expansion ratio and combustor working conditions. The combustor stability margin δ was used to divide the high-performance region, low-performance region, and instability region under limited working conditions, by which the trend of regulation under the acceleration-cruise process was obtained. Increasing the operating Mach number in the matching intervals of the equivalence ratio to the expansion ratio promoted the movement of the main heat release zone and the increase in the peak pressure ratio. The regulating paths and performance boundary of the variable geometry combustor in a wide flight domain were obtained from a large amount of steady-state/dynamic experimental data.

A Comprehensive Radiative Magnetohydrodynamics Simulation of Active Region Scale Flux Emergence from the Convection Zone to the Corona

We present a comprehensive radiative magnetohydrodynamic simulation of the quiet Sun and large solar active regions. The 197 Mm wide simulation domain spans from 18(10) Mm beneath the photosphere to 113 Mm in the solar corona. Radiative transfer assuming local thermal equilibrium, optically thin radiative losses, and anisotropic conduction transport provide the necessary realism for synthesizing observables to compare with remote-sensing observations of the photosphere and corona. This model self-consistently reproduces observed features of the quiet Sun, emerging and developed active regions, and solar flares up to M class. Here, we report an overview of the first results. The surface magneto-convection yields an upward Poynting flux that is dissipated in the corona and heats the plasma to over 1 MK. The quiescent corona also presents ubiquitous propagating waves, jets, and bright points with sizes down to 2 Mm. Magnetic flux bundles emerge into the photosphere and give rise to strong and complex active regions with over 1023 Mx magnetic flux. The coronal free magnetic energy, which is approximately 18% of the total magnetic energy, accumulates to approximately 1033 erg. The coronal magnetic field is clearly non-force-free, as the Lorentz force needs to balance the pressure force and viscous stress as well as drive magnetic field evolution. The emission measure from to provides a comprehensive view of the active region corona, such as coronal loops of various lengths and temperatures, mass circulation by evaporation and condensation, and eruptions from jets to large-scale mass ejections.

Improved reduce-order modeling of bidirectional interleaved boost with coupled inductors converter

In this paper, an improved reduced-order average modeling method for the bidirectional interleaved boost with coupled inductors (BIBCI) converter is proposed, based on the PWM and phase-shift dual-degree-of-freedom modulation and traditional reduced-order average model. Considering the power loss of the coupled inductor, the core loss, and the parasitic parameters of the inductors, capacitors, and switches in the circuit topology, the new model reflects the dynamic performance of the converter in a wide frequency domain more accurately than the traditional model. The small-signal model and transfer function are further deduced to provide a basis for the design of closed-loop controllers and have good engineering practicability. According to voltage source load or resistive load, the double-loop or triple-loop controller is designed correspondingly. The two models are theoretically analyzed and compared, and the proposed controller is verified by a 1.5 kW prototype.

Hard antiphase domain boundaries in strontium titanate unravelled using machine-learned force fields

We investigate the properties of hard antiphase boundaries in ${\mathrm{SrTiO}}_{3}$ using machine-learned force fields. In contrast to earlier findings based on standard ab initio methods, for all pressures up to $120\phantom{\rule{0.16em}{0ex}}\mathrm{kbar}$ the observed domain wall pattern maintains an almost perfect N\'eel character in quantitative agreement with Landau-Ginzburg-Devonshire theory, and the in-plane polarization ${P}_{3}$ shows no tendency to decay to zero. Together with the switching properties of ${P}_{3}$ under reversal of the N\'eel order parameter component, this provides hard evidence for the presence of rotopolar couplings. The present approach overcomes the severe limitations of ab initio simulations of wide domain walls and opens avenues toward concise atomistic predictions of domain-wall properties even at finite temperatures.

Atomic-scale spin-wave polarizer based on a sharp antiferromagnetic domain wall

We theoretically study the scattering of spin waves from a sharp domain wall in an antiferromagnetic spin chain. While the continuum model for an antiferromagnetic material yields the well-known result that spin waves can pass through a wide domain wall with no reflection, here we show that, based on the discrete spin Hamiltonian, spin waves are generally reflected by a domain wall with a reflection coefficient that increases as the domain-wall width decreases. Remarkably, we find that, in the interesting case of an atomically sharp domain wall, the reflection of spin waves exhibits strong dependence on the state of circular polarization of the spin waves, leading to mainly reflection for one polarization while permitting partial transmission for the other, thus realizing an atomic-scale spin-wave polarizer. The polarization of the transmitted spin wave depends on the orientation of the spin in the sharp domain wall, which can be controlled by an external field or spin torque. Our utilization of a sharp antiferromagnetic domain wall as an atomic-scale spin-wave polarizer leads us to envision that ultra-small magnetic solitons such as domain walls and skyrmions may enable realizations of atomic-scale spin-wave scatterers with useful functionalities.