bluuebunny/crossref_metadata_2025_split huggingface dataset:
Superharmonic instability for regularized long-wave models*
Authors: Bronski Jared C , Hur Vera Mikyoung , Lee Wester Samuel 
Published: November 2022

Abstract
We examine the spectral stability and instability of periodic traveling waves for regularized long-wave models. Examples include the regularized Boussinesq, Benney–Luke, and Benjamin–Bona–Mahony equations. Of particular interest is a striking new instability phenomenon—spectrum off the imaginary axis extending into infinity. The spectrum of the linearized operator of the generalized Korteweg–de Vries equation, for instance, lies along the imaginary axis outside a bounded set. The spectrum for a regularized long-wave model, by contrast, can vary markedly with the parameters of the periodic traveling waves. We perform rigorous spectral asymptotics for short wavelength perturbations to establish conditions under which the spectrum tends to infinity along the imaginary axis or some curve whose real part is nonzero. We conduct numerical experiments which corroborate our analytical findings.
Conditions for bound states of the pseudopotential with harmonic confinement in arbitrary dimensions
Authors: McKinney Lanie G , McKinney B A 
Published: November 2022

Abstract
We determine the conditions for bound states (E < 0) for arbitrary Cartesian dimension d using a shape-independent regularized pseudopotential with scattering length a for two cold particles in a harmonic trap. It is known for d ≤ 3 that the regularized pseudopotential supports one bound state for positive scattering length but does not support bound states for negative scattering length. We find that the usual (d ≤ 3) positive scattering length bound states rule holds for certain higher odd dimensions d = 4n + 3 (n = 0, 1, …), but the existence of pseudopotential bound states at other odd dimensions requires a negative scattering length. Specifically, bound states are allowed in higher dimensions d = 4n + 1 (n = 1, 2, …) but they require a negative scattering length, which suggests a universe in these dimensions might lead to different chemistry than d = 3. We derive analytical approximations for bound state (E < 0) and scattering (E > 0) energies for a harmonic trap perturbed by the pseudopotential in arbitrary dimensions.
Probabilistic risk assessment model for released tritium into the environment for CFETR
Authors: Liang Qingzhu , Xu Xinyan , Peng Changhong 
Published: November 2022

Abstract
The China Fusion Engineering Test Reactor (CFETR) is the next facility in the Chinese roadmap to realize sustainable-clean fusion energy. Because of the large tritium inventory of the CFETR, safety analyses are necessary. During the current design phase of the CFETR, performing the risk analysis of tritium released into the environment could reveal the design weaknesses and indicate improvements aimed at trtium risk (TR) reduction but also form a part of the licensing process for future CFETR construction and operation. Several CFETR safety analyses using deterministic approaches have been conducted, but relatively few studies based on probabilistic approaches are currently available. In this paper, a probabilistic risk assessment (PRA) model for tritium release into the environment for CFETR was proposed, in which the frequency and the radioactivity of the released tritium in accident sequences are considered. The event tree/fault tree (ET/FT) method was applied to investigate primary factors contributing to the tritium release into the environment and to estimate the frequency of accident sequences. We presented a model for preliminary and rapid assessment of the radioactivity of released tritium in accident sequences and developed a calculation code. The application process and validity of the model were demonstrated through the assessment of TR of the CFETR for selected postulated initiating events.
Optimization of irradiation configuration using spherical t-designs for laser-direct-drive inertial confinement fusion
Authors: Shvydky A. , Trickey W. , Maximov A.V. , Igumenshchev I.V. , McKenty P.W. , Goncharov V.N. 
Published: November 2022

Abstract
A new class of beam configurations is proposed for symmetric-direct-drive inertial confinement fusion laser systems. These configurations are based on spherical t-designs that are studied in spherical design theory in mathematics (Delsarte et al 1977 Geom. Dedicata
6 363). Employing t-design configurations offers elimination of spherical-harmonic intensity modulations for modes

ℓ
⩽
t

. Additionally, these configurations provide fast decay of intensity nonuniformities with increasing number of beams and symmetric intensity patterns on the surface of the target. Methods developed in spherical design theory offer a convenient, systematic way of obtaining beam configurations for an arbitrary number of beams.
Rational surfaces, flows and radial structure in the TJ-II stellarator
Authors: van Milligen B.Ph. , Voldiner I. , Carreras B.A. , García L. , Ochando M.A. 
Published: November 2022

Abstract
In this work, we report on the results obtained by measuring several turbulent quantities well inside the plasma edge by means of a Langmuir probe during dynamical rotational transform scans in the TJ-II stellarator, while applying a radial electric field to the edge plasma using a biasing probe. By calculating the intermittence parameter from floating potential measurements, we are able to identify a major low order rational surface and hence relate the probe measurements to the local value of the rotational transform. Based on the former, we are able to show that the poloidal plasma velocity (and hence radial electric field) has a significant radial structure that is clearly related to the rotational transform profile and in particular the lowest order rational surfaces in the range studied. The poloidal velocity is also affected by the edge biasing. The particle flux Γ was also found to exhibit a radial pattern, as did the flow shear suppression term

ω

E
×
B

, but the relation of the former to the low-order rational surfaces was less clear. We surmise that this lack of direct correspondence is due to an unknown term in the turbulence evolution equation: the instability growth rate, γ. We make use of a reduced Magnetohydrodynamic turbulence model to interpret the results. Overall, a picture is obtained in which the plasma self-organizes towards a state with a clear radial pattern of the radial electric field, in line with expectations from some numerical studies describing the spontaneous formation of an ‘E × B staircase’, consisting of alternating layers with fast and slow radial transport. In this state, the radial profiles of various quantities (density, temperature, pressure) will not be smooth.
Performance studies of Micromegas electronics in a high radiation environment at the CERN Gamma Irradiation Facility (GIF++)
Authors: Kolitsi Foteini , Alexopoulos Theodoros , Bita Daniel , Iakovidis George , Kitsaki Chara , Kyriakis-Bitzaros Efstathios , Mesolongitis Ioannis , Zachariadou Katerina 
Published: November 2022

Abstract
The ATLAS experiment at CERN undergoes a series of upgrades, in line with the upgrades (Phase-I and Phase-II) of the Large Hadron Collider (LHC), to cope with the steadily increasing instantaneous luminosity that ultimately is expected to reach 7.5×1034cm−2 s−1 at the High Luminosity LHC (HL-LHC) era. The most challenging upgrade project of the ATLAS experiment concerns its Muon Spectrometer’s inner wheel-shaped detection stations (Small Wheels) located close to and on either side of the pp beams’ interaction point. Another type of detection system (New Small Wheels) replaced the two Small Wheels so that the ATLAS maintains its performance while preserving the acceptance of critical physics signatures under the harsh conditions of higher data and radiation rates (up to 25kHz/cm2 at the HL-LHC accelerator). The NSWs are a complex detection system (each wheel comprises 2.4x106 readout channels)that employ two novel micro-pattern gaseous detector technologies, the Micromesh Gaseous Structure (Micromegas, MM) and the small strip Thin Gap Chambers (sTGCs), mainly to improve the trigger performance and to provide precise spatial measurements. New electronic boards residing on the detectors were designed and manufactured, hosting high radiation and magnetic field tolerant custom-made ASICs.This paper presents extensive tests carried out at the new CERN Gamma Irradiation Facility (GIF++) by combining a muon beam (of 12kHz) with a 137Cesium radiation source of adjustable rate (up to ten times the expected rate at the HL-LHC conditions), to assess the performance of the Micromegas chambers and their readout electronics. Data from NSW Micromegas modules of different detection areas, having different positions on the wheels, operating with different high voltage and filling gas have been read out and analyzed by placing the electronics on PCBs located at various distances from the pp beam pipe. The spatial resolution of the precision coordinate is found to be well below the required 100μm, and the excellent alignment of the precision layers has been verified. Results confirm that all types of Micromegas modules tested have a linear response up to a rate around four times the expected at HL-LHC.
Reply to Comment on ‘Egypt’s water budget deficit and suggested mitigation policies for the Grand Ethiopian Renaissance Dam filling scenarios’ by Kevin Wheeler et al’
Authors: Heggy Essam , Sharkawy Zane , Abotalib Abotalib Z 
Published: November 2022

Abstract
We thank Wheeler et al for positively confirming our results’ reproducibility; however, we show herein that their critique misrepresents the aim, approach, and interpretations reported in Heggy et al (2021 Environ. Res. Lett.
16 074022), which remain valid. The reply herein demonstrates that Wheeler et al incorrectly interpreted Heggy et al’s (2021 Environ. Res. Lett.
16 074022) estimates of the median unmitigated total water budget deficit for Egypt of 31 BCM yr−1 to be entirely caused by GERD. The comment overlooks the fact that this estimated value is the sum of Egypt’s existing intrinsic deficit (18.5 BCM yr−1), the initial reservoir seepage (2.5 BCM yr−1), and the median dam impoundment (9.5 BCM yr−1) under different GERD filling scenarios ranging from 2.5 to 29.6 years as shown in figure 2 and section 3.1 in Heggy et al (2021 Environ. Res. Lett.
16 074022). Consequently, our evaluation of the deficit was mistakenly deemed exaggerated as well as the socioeconomic impacts that rely on its estimate. These misinterpretations led to inappropriate comparisons between the results of the unmitigated total water budget deficit under the shortest filling scenario in Heggy et al (2021 Environ. Res. Lett.
16 074022) with longer ones from other studies that focus exclusively on GERD impoundment and assess the economic impacts of water shortage after applying several suggested mitigations that are not yet formally agreed upon, implemented, or budgeted. Instead, Heggy et al (2021 Environ. Res. Lett.
16 074022) provided a holistic evaluation of the current status of the total water budget deficit in Egypt (including intrinsic and GERD components) and its equivalent economic representation to support decision-makers in better implementing the fourth statement of the declaration of principles between the Nile’s riparian countries. The suggestion that the results of the unmitigated scenarios in Heggy et al (2021 Environ. Res. Lett.
16 074022) should match those of the mitigated ones cited in Wheeler et al is erroneous from both hydrological and policy perspectives.
Two deep learning-based bias-correction pathways improve summer precipitation prediction over China
Authors: Ling Fenghua , Li Yue , Luo Jing-Jia , Zhong Xiaohui , Wang Zhibin 
Published: November 2022

Abstract
As most global climate models (GCM) suffer from large biases in simulating/predicting summer precipitation over China, it is of great importance to develop suitable bias-correction methods. This study proposes two pathways of bias-correction with deep learning (DL) models incorporated. One is the deterministic pathway (DP), in which the bias correction is directly applied to the precipitation forecasts. The other one, namely the probability pathway (PP), corrects the forecasted precipitation anomalies using a conditional probability method before being added to the observational climatology. These two pathways have been applied to correct the precipitation forecasts based on a GCM prediction system Nanjing University of Information Science and Technology Climate Forecast System version 1.0 (NUIST-CFS1.0). The applications of DL models in the both pathways yield higher resolution of corrected predictions than the uncorrected ones. Both pathways improve summer precipitation predictions at 4-month lead. Moreover, the DP correction shows a better performance in predicting extreme precipitation, while the PP is proficient in correcting the spatial pattern of precipitation anomalies over China. The present results highlight the importance of the application of appropriate correction strategy for different prediction purposes.
Uncertainty constraints on economic impact assessments of climate change simulated by an impact emulator
Authors: Shiogama Hideo , Takakura Jun’ya , Takahashi Kiyoshi 
Published: November 2022

Abstract
Since many new generation Earth system models (ESMs) have been suggested to overestimate future global warming, the latest report of the Intergovernmental Panel on Climate Change used the constrained range of global warming instead of that in the raw ensemble. However, it is not clear how the constraints of climate change projections potentially reduce the uncertainty of impact assessments. Here, we show that the climate-related uncertainty of the economic impact of climate change in the world can be constrained. By applying an impact emulator, we estimate the economic impacts in nine sectors based on 67 ESMs’ future climate change projections and find that the impacts in eight sectors are closely related to the recent past trend of global mean temperature, which is the metric used for the constraint of global warming projections. Observational constraints lower the upper bound of the aggregate economic impact simulated by the single emulator from 2.9% to 2.5% of the world gross domestic product (the relative reduction of variance is 31%) under the medium greenhouse gas concentration scenarios. Our results demonstrate how advances in climate science can contribute to reducing climate-related uncertainties in impact assessments, while we do not examine uncertainties of emulators and impact models.
Quantum spin dynamics of quasi-one-dimensional Heisenberg-Ising magnets in a transverse field: confined spinons, E
8 spectrum, and quantum phase transitions
Authors: Amelin Kirill , Viirok Johan , Nagel Urmas , Rõõm Toomas , Engelmayer Johannes , Dey Tusharkanti , Agung Nugroho Agustinus , Lorenz Thomas , Wang Zhe 
Published: November 2022

Abstract
We report on high-resolution terahertz spectroscopic studies of quantum spin dynamics in the quasi-one-dimensional Ising-like ferromagnet CoNb2O6 and antiferromagnet BaCo2V2O8 as a function of an applied transverse magnetic field. In the ordered phases stabilized by inter-chain couplings, we reveal characteristics for confined spinon excitations, E
8 dynamical spectrum, and field-induced quantum phase transitions. The connections between these characteristic dynamical features are found in the field-dependent evolution of the excitation spectra.
Strong dispersion property for the quantum walk on the hypercube
Authors: Kokainis M , Prūsis K , Vihrovs J , Kashcheyevs V , Ambainis A 
Published: November 2022

Abstract
We show that the discrete time quantum walk on the Boolean hypercube of dimension n has a strong dispersion property: if the walk is started in one vertex, then the probability of the walker being at any particular vertex after O(n) steps is of an order

O
(

1.4818

−
n

)

. This improves over the known mixing results for this quantum walk which show that the probability distribution after O(n) steps is close to uniform but do not show that the probability is small for every vertex. Our result shows that quantum walk on hypercube is interesting for algorithmic applications which require fast dispersion over the state space.
An exact, time-dependent analytical solution for the magnetic field in the inner heliosheath
Authors: Röken Christian , Kleimann Jens , Fichtner Horst 
Published: November 2022

Abstract
We derive an exact, time-dependent analytical magnetic field solution for the inner heliosheath, which satisfies both the induction equation of ideal magnetohydrodynamics in the limit of infinite electric conductivity and the magnetic divergence constraint. To this end, we assume that the magnetic field is frozen into a plasma flow resembling the characteristic interaction of the solar wind with the local interstellar medium. Furthermore, we make use of the ideal Ohm’s law for the magnetic vector potential and the electric scalar potential. By employing a suitable gauge condition that relates the potentials and working with a characteristic coordinate representation, we thus obtain an inhomogeneous first-order system of ordinary differential equations for the magnetic vector potential. Then, using the general solution of this system, we compute the magnetic field via the magnetic curl relation. Finally, we analyze the well-posedness of the corresponding Dirichlet-type initial-boundary value problem, specify compatibility conditions for the initial-boundary values, and outline the implementation of initial-boundary conditions.
Theoretical study on fabrication of sub-wavelength structures via combining low-order guided mode interference lithography with sample rotation
Authors: Ren Yaqian , Wang Xiangxian , Di Xiujuan , Jia Tianxu , Chen Tianshan , Zhang Liping , Yang Hua , Qi Yunping , Tang Chaojun 
Published: November 2022

Abstract
Guided mode interference lithography based on a symmetric metal-cladding dielectric waveguide structure (a resist between two metal layers), is studied. The low-order guided modes in the waveguide structure excited by 325 nm laser, and then sub-wavelength gratings with half-periods of 47 nm (

λ

/6.91) and 60 nm (

λ

/5.42) can be obtained by excited TM0 and TE0 guided modes, respectively. Among them, the period of the sub-wavelength grating fabricated by TM0 guided mode interference is smaller, but it is limited by the thickness of resist. TE0 guided mode interference is more suitable for thick resist. On this basis, taking TM0 guided mode as an example, periodic sub-wavelength structures, such as square lattice and quasi-hexagonally close-packed structure, can be obtained by rotating and exposing the sample in different ways. The proposed method of combining guided mode interference lithography with sample rotation has simple operation and low cost, and provides a theoretical reference for fabricating two-dimensional sub-wavelength structures.
Validation of the current and pressure coupling schemes with nonlinear simulations of TAE and analysis on the linear stability of tearing mode in the presence of energetic particles
Authors: ZHANG Haowei , MA Zhiwei 
Published: November 2022

Abstract
Both current and pressure coupling schemes have been adopted in the hybrid kinetic–magnetohydrodynamic code CLT-K recently. Numerical equivalences between these two coupling schemes are strictly verified under different approximations. First, when considering only the perturbed distribution function of energetic particles (EPs), the equivalence can be proved analytically. Second, when both the variations of the magnetic field and the EP distribution function are included, the current and pressure coupling schemes numerically produce the same result in the nonlinear simulations. On this basis, the influences of co-/counter-passing and trapped EPs on the linear stabilities of the m/n = 2/1 tearing mode (TM) have been investigated (where m and n represent the poloidal and toroidal mode numbers, respectively). The results of scanning

β

h

of EPs show that the co-passing and trapped EPs are found to stabilize the TM, while the counter-passing EPs tend to destabilize the TM. The behind (de)stabilization mechanisms of the TM by EPs are carefully analyzed. Furthermore, after exceeding critical EP betas, the same branch of the high-frequency mode is excited by co-/counter-passing and trapped EPs, which is identified as the m/n = 2/1 energetic particle mode.
An experience based artificial neural network in the design optimization of steel frames
Authors: Jahjouh Mahmoud 
Published: November 2022

Abstract
The design of steel frames is an iterative process relying on the experience and decisions of the designer to achieve economical and safe designs. With recent advances in artificial intelligence, particularly, artificial neural networks, it became possible to train such networks to simulate an experienced designer. Thus, the aim of this contribution is to investigate the possibility of artificial neural networks gaining design experience and using such experience in predicting adequate and economical designs. To achieve this aim, an adaptive harmony search algorithm is used to obtain the optimum structural design of two-dimensional steel frames. Those designs are, in a sense, considered an experience, which are then used in training artificial neural networks. The trained networks are finally used in predicting the optimum solution of new problem variants. In total, 18684 samples based on 3114 two-dimensional frames were used to train multiple feed forward artificial neural networks, with a training, validation and testing ratios of 70%, 15% and 15%, respectively. The trained networks’ performance was verified, and used in design predictions on interpolated and extrapolated cases. Considering the designs suggested by the artificial neural networks, 99% were adequate in the case of network verification. Furthermore, 97% and 93% of designs were adequate in the case of interpolation and extrapolation. Thus, artificial neural networks are able to learn from the design experience and provide good approximations for designs of variants even outside the training set. Such findings encourage the development of artificial intelligence assisted design systems that are capable of suggesting optimum or near-optimum designs for two-dimensional frames. Also, it could encourage further research for three-dimensional steel frames and more complex steel structure systems.