bluuebunny/crossref_metadata_2025_split huggingface dataset:
Remarks on the separation of Navier–Stokes flows
Authors: Bradshaw Zachary 
Published: August 2024

Abstract
Recently, strong evidence has accumulated that some solutions to the Navier–Stokes equations in physically meaningful classes are not unique. The primary purpose of this paper is to establish necessary properties for the error of hypothetical non-unique Navier–Stokes flows under conditions motivated by the scaling of the equations. Our first set of results show that some scales are necessarily active—comparable in norm to the full error—as solutions separate. ‘Scale’ is interpreted in several ways, namely via algebraic bounds, the Fourier transform and discrete volume elements. These results include a new type of uniqueness criteria which is stated in terms of the error. The second result is a conditional predictability criteria for the separation of small perturbations. An implication is that the error necessarily activates at larger scales as flows de-correlate. The last result says that the error of the hypothetical non-unique Leray–Hopf solutions of Jia and Šverák locally grows in a self-similar fashion. Consequently, within the Leray–Hopf class, energy can hypothetically de-correlate at a rate which is faster than linear. This contrasts numerical work on predictability which identifies a linear rate. Our results suggest that this discrepancy may be explained by the fact that non-uniqueness might arise from perturbation around a singular flow.
Scaling of the emission of low frequency radiation by transient surface currents in laser–solid interactions
Authors: Robinson A P L 
Published: August 2024

Abstract
It has been suggested that ‘transient surface currents’ caused by multi-MeV fast electrons can be responsible for the emission of low frequency radiation (e.g. in THz range) from ultra-intense laser–solid interactions. This mechanism has been analyzed, and analytic upper bounds on the intensity, electric field amplitude, and normalized vector potential have been developed and tested against 1D EM Particle-in-Cell simulations. The ‘transient surface current’ mechanism is effective and sufficiently efficient to fully account for all radiation that has been emitted in experiments so far.
Temperature- and gate voltage-dependent I–V modeling of GaN HEMTs based on ASM-HEMT
Authors: Zhou Ziwei , Liu Guipeng , Zhao Guijuan 
Published: August 2024

Abstract
In this paper, a temperature- and gate voltage-dependent current–voltage (I–V) model for gallium nitride (GaN) high electron mobility transistors (HEMTs) devices is studied. To help researchers and designers simulate devices in the absence of experimental data and improve the parameter extraction efficiency, the temperature and gate voltage dependence of mobility are discussed and incorporated into the proposed model, which is revised from the standard advanced SPICE model (ASM) for GaN HEMTs. The mobility variations with the gate voltage from −2 V to 6 V and the temperature from 10 K to 1000 K are analyzed. The simulation results of our model are compared with the standard ASM-HEMT model, and the output and transfer characteristics of the device from 270 K to 420 K are simulated. Therefore, our model may simulate various applications of GaN HEMTs at different gate voltages and temperatures in the early stages of design and research.
A comparative analysis of the tribological performance of coir, bamboo and wood filler reinforced polymer composites
Authors: Paul Rajdeep , Mahakur Vijay Kumar , Bhowmik Sumit 
Published: August 2024

Abstract
Researchers and academics are increasingly favoring natural fibres for incorporation into polymer composites on account of their ecological compatibility and longevity. The aim of this comparative study is to identify the optimal natural filler by AHP-TOPSIS approach by analyzing the tribological performance of three distinct natural fillers: coir, bamboo, and wood reinforced polymer composite. These filler materials are pre-treated by alkali treatment to increase the interlinking properties between filler and polymer. The outcome of these treatments on the composites’ physical and mechanical properties are investigated. Using a Pin-on-disk (POD) machine under dry, wet, and heated sliding contact conditions, different natural fillers’ effects on polymer wear and friction are examined. The wear rate and coefficient of friction (COF) were quantified as a function of the sliding distance (0–2000 m) under various normal loads (5–40 N). It was observed from the different experimental results that coir filler reinforced composite shows best wear resistance property whereas wood filler reinforced composite shows the least wear resistance composite. Results revealed that lower filler support and low load show better wear resistant property compared to the higher filler support and high load condition. When seen through a microscope, the worn surfaces of the composite material exhibit micro and macro fissures, as well as debonding and plastic deformation. The coir filler-based composite was found to be the best alternative using the AHP-TOPSIS method, with a closeness coefficient of 0.770023.
Design and analysis of discrete fractional-order chaotic map with offset-boosting behavior
Authors: Huang Lilian , Zheng Lei , Yang Yan , Yu Xihong , Li Chuang 
Published: August 2024

Abstract
Fractional calculus, as a more accurate tool for depicting the dynamics of complex systems, has been introduced into discrete chaotic maps. To further describe the offset-boosting behavior in discrete systems, a discrete fractional-order chaotic map (DFOCM) based on the Caputo difference operator is constructed. The mapping order of this fractional-order model controls the stability of the fixed point, thereby affecting the dynamic behavior of the map. The dynamics of DFOCM is studied using numerical simulation methods such as bifurcation diagrams and maximum Lyapunov exponents, revealing the presence of multistability. By comparing with integer-order map, it is found that DFOCM exhibit a larger chaotic region. Based on this, the difference between fractional order and integer order offset-boosting behavior is theoretically derived. Specifically, the offset-boosting behavior of fractional-order maps concerning mapping parameters is related to the initial state, which was further demonstrated through numerical simulations. SE complexity proves that the chaotic sequences generated by DFOCM have high unpredictability and pseudo-randomness. Finally, the proposed DFOCM is implemented on the DSP hardware platform, and the physical feasibility of numerical simulation is verified.
Optical soliton solutions of the nonlinear complex Ginzburg-Landau equation with the generalized quadratic-cubic law nonlinearity having the chromatic dispersion
Authors: Esen Handenur , Secer Aydin , Ozisik Muslum , Bayram Mustafa 
Published: August 2024

Abstract
In this study, we consider the complex Ginzburg-Landau equation with the generalized quadratic-cubic law of self-phase modulation. This model finds applications in various fields, such as the study of superconductivity, nonlinear optical phenomena, pattern formation, and designing photonic devices and systems. This manuscript successfully employs the new Kudryashov method to derive analytical solutions for complex Ginzburg-Landau equations with the generalized quadratic-cubic law of self-phase modulation. The 3D, contour, and 2D graphical representations of the acquired solutions are represented. Therefore, W-shaped, bright, and dark soliton structures are derived. Through rigorous analysis and interpretation, valuable insights into the influence of the parameters of the presented model on the soliton behavior are achieved.
Theoretical study of the MWCNT particle layer and size impact on sodium alginate heat transfer
Authors: Akinshilo A T , Folaranmi A , Ilegbusi A O 
Published: August 2024

Abstract
This paper theoretically studies the effects of the size of multiwalled carbon nanotube (MWCNT) nanoparticles and layers on the flow of sodium alginate (SA) base fluid in a vertical channel. The nanoparticles are used to improve the thermal characteristics of the base fluid. The nanolayer shows the relationship between the particles and the base fluid, justifying the rise in thermal conductivity, even at a low volume of the nanoparticle in the base fluid. The mechanics of the fluid through the channels are developed using nonlinear models of coupled higher order differentials analyzed using the adomian decomposition method, an analytical scheme. The nanolayer effect of MWCNT particles on pure sodium alginate enhances heat transfer by 31.83% upon a step increase of 0.4 from 0.2 nm. Additionally, the combined effects of the rheological parameters of particle size, radiation and shear stress lead to a high heat transfer rate. The results obtained from the analysis were verified with results obtained from the literature for simple conditions, which validated the analysis. The results of this study may provide meaningful insight into the physical application of the sodium alginate.
Multi-physics modeling of tungsten collector probe samples during the WEST C4 He campaign
Authors: Lasa A. , Blondel S. , Curreli D. , Drobny J. , Garcia W.A. , Gunn J. , Hayes A. , Lore J.D. , Renganathan A. , Tsitrone E. , Unterberg E. , Wirth B.D. 
Published: August 2024

Abstract
We describe the results of a multi-scale, multi-physics modeling assessment of SOLPS-ITER, hPIC2, RustBCA and Xolotl, in which five single-crystal tungsten (W) samples were placed in a reciprocating collector probe and exposed to helium (He) plasma in the WEST fusion device. In our models, we considered a pure (100 %) He plasma, as well as one with oxygen (O) present (95% He 5% O) corresponding to the impurity concentration estimated during the C4 He campaign in WEST. Our SOLPS simulations approximately match experimental reciprocating Langmuir probe plasma measurements of plasma density and temperature. Using these plasma parameters as input, hPIC2 and RustBCA predict that the presence of oxygen impurities lead to a 15%–20% decrease in ion and heat fluxes to the surface, and an order of magnitude higher sputtering yields (compared with a pure He plasma). Xolotl predictions for the response of tungsten to plasma surface interactions (PSIs) agree with experimental LAMS analysis, and indicate large near-surface He concentrations, which quickly decay with depth. Our model also shows an increasing role of erosion—in removing the near-surface He—with time. Overall, slightly higher retention is predicted for tungsten exposed to a pure He plasma, with the largest differences in the near-surface gas content caused by the large oxygen-induced erosion. This highlights the important role that impurities play in PSI. Therefore, future work will focus on providing a fully self-consistent description of oxygen (and oxides, etc.) in our models, through multi-species implementation in GITR and inclusion of oxygen and tungsten oxide formation in Xolotl.
Observation of tungsten emission spectra up to W46+ ions in the Large Helical Device and contribution to the study of high-Z impurity transport in fusion plasmas
Authors: Oishi Tetsutarou , Morita Shigeru , Kato Daiji , Murakami Izumi , Sakaue Hiroyuki A. , Goto Motoshi , Kawamoto Yasuko , Kawate Tomoko , Nishimura Ryota , Takahashi Hiroyuki , Tobita Kenji 
Published: August 2024

Abstract
Spectroscopic studies of emissions released from tungsten ions combined with a pellet injection technique have been conducted in Large Helical Device for contribution to the tungsten transport study in tungsten divertor fusion devices and for expansion of the experimental database of tungsten line emissions. The spectral intensities of W5+, W24+–W28+, W37+, W38+, W41+–W43+, W45+, and W46+ emission lines were measured simultaneously over a wide wavelength range from x-ray to visible. Time evolutions of the various tungsten line spectra indicate that the tungsten confinement time depends on the electron density of the plasma and is long in high density plasmas, on the order of seconds, and short in low density plasmas, on the order of sub-seconds. When the confinement time was long, the tungsten ions remained in the plasma until the end of the discharge, changing their dominant charge with the change in electron temperature. When the confinement time was short, the tungsten ions rapidly decreased in all charge states and disappeared. Space-resolved EUV and visible spectroscopy measurements have revealed that tungsten ions stayed in the core region of the plasma with changing their dominant charge state depending on the electron temperature in the discharges with the long confinement time. Detailed analysis of soft x-ray emission suggested that the confinement time increases with density and becomes saturated when the central electron density exceeds 2 × 1013 cm−3.
Formation of orientation-dependent surface morphologies on tungsten after low energy helium plasma exposure: multiscale characterization and new insights
Authors: Zhu Yi-Wen , Li Yu , Sun Yuhan , Liu Hao-Dong , Yang Xin , Cheng Long , Yuan Yue , Lu Guang-Hong , Luo Guang-Nan , Zhou Hai-Shan 
Published: August 2024

Abstract
In ITER, the helium (He) impurity produced by the deuterium-tritium reaction will bombard the tungsten (W) divertor armor at the strike points. Consequently, strong interaction occurs therein that both impact the performance of the plasmas and the lifetime of the divertor. Despite an ever-increasing understanding of this interaction, some experimental phenomena remain mysterious, especially the formation of orientation-dependent surface morphologies. Here, we combine multiscale experimental characterization and theoretical models to shed new light on this problem. After low-energy He plasma exposure in a linear plasma generator, the polycrystalline W surface developed various morphologies. Through electron backscatter diffraction analysis, we found that the {111} grains developed cube-corner structures, the {110} grains developed ripple structures, whereas the {100} grains remained smooth. Then, electron-transparent lamellae were extracted from such grains to observe the subsurface He bubbles by transmission electron microscopy. The volume density, size distribution, and depth range of the He bubbles weakly depend on the crystallographic orientation, suggesting that the migration of W atoms causes the morphology variety. Accordingly, we proposed a two-stage formation mechanism. First, W atoms generated by over-pressurized He bubbles glide on the slip plane and in the slip direction to reach the surface, forming characteristic patterns that are enclosed by the slip traces. Second, morphological instability drives the evolution of the surface patterns, in which the initial surface structure and surface self-diffusion kinetics mediate. The proposed mechanism has been incorporated into a topographical instability model to enable asemi-quantitative analysis. The obtained new insights are valuable to the impurity control of the core plasmas and the lifetime analysis of the divertor for ITER.
Fault diagnosis method for elevator carriages based on temporal generative federated distillation
Authors: Zhang Guowei , Li Cong , Sun Qi 
Published: August 2024

Abstract
Addressing the ‘data silo’ issue among different elevator operating units and the temporal correlations in elevator vibration signals, a novel small-sample fault diagnosis method for elevator carriages based on temporal generative federated distillation is proposed. This method incorporates a temporal generative adversarial network into Federated Distillation via Generative Learning (FedGen). FedGen combines federated learning, knowledge distillation, and generative models to enhance model aggregation efficiency while mitigating data heterogeneity. However, the original generative model struggles to maintain dynamic correlations between signals when extracting temporal features. Therefore, an improved Time Series Generative Adversarial Networks (TimeGAN) model is introduced, substituting the initial logarithmic loss function with a least squares error function, thereby enhancing training stability and data quality. This approach eliminates the need for proxy datasets in knowledge distillation, avoiding the loss of temporal information during central server feature extraction. Simulation results demonstrate that this method enables data sharing while protecting data privacy, and enhances model generalization capabilities.
Noncommutative Coordinates for Symplectic Representations
Authors: Alessandrini Daniele , Guichard Olivier , Rogozinnikov Eugen , Wienhard Anna 
Published: August 2024

We introduce coordinates on the spaces of framed and decorated representations of the fundamental group of a surface with nonempty boundary into the symplectic group

S
p
(
2
n
,

R

)

Sp(2n,\mathbf R)

. These coordinates provide a noncommutative generalization of the parametrizations of the spaces of representations into

S
L
(
2
,

R

)

SL(2,\mathbf R)

or

P
S
L
(
2
,

R

)

PSL(2,\mathbf R)

given by Thurston, Penner, Kashaev and Fock–Goncharov. On the space of decorated symplectic representations the coordinates give a geometric realization of the noncommutative cluster-like structures introduced by Berenstein–Retakh. The locus of positive coordinates maps to the space of framed maximal representations. We use this to determine an explicit homeomorphism between the space of framed maximal representations and a quotient by the group

O
(
n
)

O(n)

. This allows us to describe the homotopy type and, when

n
=
2

n=2

, to give an exact description of the singularities. Along the way, we establish a complete classification of pairs of nondegenerate quadratic forms.
A List of Early Modern Spanish Literary Texts with Black Characters
Authors: Berruezo-Sánchez Diana 
Published: August 2024

Abstract
This Appendix lists pieces of early modern Spanish literature that contain black characters. There have been several useful previous inventories, but the list here augments the former works by collecting the details of sixteenth- and seventeenth-century literary texts with black characters who have a voice, whether they have major or minor roles. The primary purpose of this chart is to provide not just numbers and bibliographic details but also a clear picture of the literary impact of early modern black Africans. The list itemises ninety pieces of literature, including poems, novels, short stories, and theatrical texts, which, along with the three hundred villancicos de negros explored in chapter 3 (including fourteen newly edited ones in Appendix C), make for a total of nearly four hundred literary texts depicting blackness—a remarkably large number that highlights the need for scholars to reconsider the reasons behind the trend.
Fourteen New Villancicos de Negros
Authors: Berruezo-Sánchez Diana 
Published: August 2024

Abstract
This Appendix offers the edition of fourteen villancicos de negros that have not yet been catalogued in a modern collection nor mentioned in major volumes about early modern Spanish villancicos. These editions and translations are sourced from a number of original seventeenth-century manuscripts at the Biblioteca Nacional de España and the Hispanic Society of America and contain villancicos de negros that were performed in Spain as early as 1616. These fourteen newly collected poems exhibit some of the most salient, well-known features of villancicos de negros, while providing further material for a more comprehensive picture of this important seventeenth-century genre. Each villancico is accompanied by an introduction showing features of black communities in early modern Spain discussed in the book.
Comparison of antigenicity between frozen section vs non−frozen section tissue blocks: An immunohistochemical study of antibodies commonly used in gynecologic pathology
Authors: Obaid Quratulain , Nadji Mehrdad , Schlumbrecht Matthew , Pinto Andre 
Published: August 2024

Abstract

Objectives
Frozen section (FS) is a technique widely used intraoperatively to render a preliminary histopathologic diagnosis, allowing for immediate decisions at the time of surgery. We aimed to investigate potential variations in tissue antigenicity induced by rapid freezing in a variety of gynecologic tumor samples.

Methods
A total of 177 FS and 177 non–frozen section (NFS) tissue slides were tested using a panel of immunostains commonly used in gynecologic pathology, including hormone receptors (estrogen receptor, progesterone receptor), HER2, mismatch repair proteins (MSH6, PMS2), programmed cell death 1 ligand 1 (PD-L1), p53, napsin A, and ɑ-methylacyl coenzyme-A racemase. Immunohistochemistry results were categorized as positive or negative, and positive cases were subsequently scored based on the distribution and intensity of the staining. Certain immunostains, such as HER2, PD-L1, and p53, were scored according to the established guidelines.

Results
The overall concordance between FS and NFS blocks was 87%; among the 13% of discrepant cases, most (10.7%) were classified as minor, with only quantitative differences without foreseeable clinical significance. In 2.3% of cases, there were major qualitative changes with potential impact on disease management.

Conclusions
We concluded that FS tissue blocks may, in most cases, safely be used for immunohistochemical studies because most discrepant cases showed only minor differences in staining, with no anticipated clinical significance. Nevertheless, for certain markers, including HER2, p53, and PMS2, a NFS block is preferred when that option is available.
Association of a novel restrictive housing diversion program with rates of mental health and self-injury in prison
Authors: Remch Molly , Swink Gregory , Mautz Charles , Austin Anna E , Naumann Rebecca B 
Published: August 2024

Abstract
Restrictive housing for control purposes (RHCP, a form of solitary confinement) is used in prisons in response to disruptive behaviors, including violence. North Carolina prisons introduced the rehabilitative diversion unit (RDU) in 2016 as an alternative to and stepdown from RHCP. We compared rates of psychiatric treatment and self-injury among men enrolled in the RDU and men eligible for the RDU but placed in RHCP. We used Poisson regression to calculate rate ratios (RRs) and 95% confidence intervals (CIs) for these outcomes, using inverse probability of treatment weights to adjust for confounders. The cohort included 1225 men in the RDU group and 3059 in the RHCP group. In RHCP, the adjusted psychiatric treatment rate was 2.6 times (95% CI, 1.8-3.8) and the adjusted self-injury incident rate was 1.2 times (95% CI, 0.6-2.8) that in RDU. Nearly all self-injury incidents in RDU occurred during “nonparticipating time” (ie, in a restrictive housing setting and not actively participating in RDU). After excluding nonparticipating time from the RDU group’s person time, the adjusted RR for self-injury incidents was 23.5 (95% CI, 8.6-64.2). These results further knowledge of potential benefits of diversion from restrictive housing. Continued development, implementation, and evaluation is needed.