bluuebunny/crossref_metadata_2025_split huggingface dataset:
State geometric adjustability for interval max‐plus linear systems
Authors: Yin Yingxuan , Chen Haiyong , Tao Yuegang 
Published: October 2024

AbstractThis article investigates the state geometric adjustability for interval max‐plus linear systems, which means that the state vector sequence is transformed into a geometric vector sequence by using the state feedback control. It is pointed out that the geometric state vector sequence and its common ratio are closely related to the eigenvectors and eigenvalues of the special interval state matrix, respectively. Such an interval state matrix is determined by the eigen‐robust interval matrix, which has a universal eigenvector relative to a universal eigenvalue. The state geometric adjustability is characterized by the solvability of interval max‐plus linear equations, and a necessary and sufficient condition for the adjustability is given. A polynomial algorithm is provided to find the state feedback matrix. Several numerical examples and simulations are presented to demonstrate the results. At the same time, the proposed method is applied for the regulation of battery energy storage systems to optimize the start time of executing tasks for all processing units in each activity.
Cooperative control of mixed vehicle platoon based on pinning consensus of heterogeneous multi‐agent system
Authors: Du Wenju , Ma Changxi , Zhang Jiangang 
Published: October 2024

AbstractThis paper proposes a longitudinal controller for the mixed vehicle platoon in the presence of driver response time‐delay and communication time‐delay based on the pinning consensus of heterogeneous multi‐agent system. Firstly, an adaptive pinning consensus control protocol and derive sufficient conditions for the heterogeneous non‐linear multi‐agent system are designed to achieve pinning consistency. Then, the heterogeneous characteristics of the vehicle are described based on the car‐following model, then the mixed vehicle platoon system model is constructed and a mixed vehicle platoon controller based on heterogeneous multi‐agent pinning consensus is proposed. Besides, the driver response time‐delay and communication time‐delay are introduced into the model, and a controller based on time‐delay heterogeneous multi‐agent pinning consensus is designed. Finally, the effectiveness of the proposed controller is verified by numerical simulations, and the effect of number of connected autonomous vehicle, different types of vehicle order, driver response time‐delay, communication time‐delay and the parameter of the controller on stability of mixed vehicle platoon is also quantitatively demonstrated.
Analysis of the possible detection of the pulsar wind nebulae of PSR J1208-6238, J1341-6220, J1838-0537, and J1844-0346
Authors: Zhang Wei , Torres Diego F. , García C. R. , Li J. , Mestre Enrique 
Published: October 2024

Context. Pulsar wind nebulae (PWNe) are a source of very high energy radiation that can reach up to tera-electron volts and even peta-electron volts. Our work uses the pulsar tree, a graph theory tool recently presented to analyze the pulsar population and select candidates of interest.
Aims. We aim to discover detectable PWNe. We also aim to test to what extent the pulsar tree is able to group detectable PWNe despite only considering the intrinsic properties of pulsars.
Methods. We selected four pulsars as tera-electron volt PWNe candidates based on their positions in the pulsar tree. Using observed and assumed ranges of values for relevant parameters, we anticipated the possible spectral energy distributions of the PWNe of four pulsars (PSR J1208-6238, J1341-6220, J1838-0537, and J1844-0346) via a detailed time-dependent leptonic model that was already found to be appropriate for describing almost all other detected nebulae.
Results. We estimated the likelihood of detection for the four candidates we studied by comparing the TeV fluxes predicted by the possible models with the sensitivities of different observatories. In doing so, we provide context for analyzing the advantages and caveats of using the pulsar tree position as a marker for properties that go beyond the intrinsic features of pulsars that are considered in producing the pulsar tree.
Temporal and chromatic variation of polarized scattered light in the outer disk of PDS 70
Authors: Ma J. , Ginski C. , Tazaki R. , Dominik C. , Schmid H. M. , Ménard F. 
Published: October 2024

Context. PDS 70 stands out as the only system hosting a protoplanetary disk and two confirmed planets undergoing formation. It is a unique target for characterizing the dust in this type of disk.
Aims. We aim to accurately measure the reflected polarized intensity and quantify the variability and asymmetry for PDS 70 across multiple epochs and wavelengths in the optical and near-infrared. We present new high-contrast polarimetric differential imaging observations of PDS 70, with the N_R filter on SPHERE/ZIMPOL.
Methods. We combined the new observation with archival data of the VLT/SPHERE instrument, spanning five wavelengths (N_R, VBB, J, H, and Ks) over seven epochs and eight years. For each observational epoch, we corrected the smearing effect due to finite instrument resolution, measured the azimuthal brightness profiles, and derived the intrinsic disk-integrated polarized reflectivity and the intrinsic brightness contrasts.
Results. With our homogeneous analysis of all available optical and near-infrared data sets of the disk around PDS 70, we find significant temporal variability of the integrated polarized reflectivity as well as the azimuthal brightness profile. This indicates variable shadowing on the outer disk by inner disk structures beyond the resolution limit of current imaging instruments. Despite these variabilities, we observe a systematic wavelength-dependent contrast between the near side and the far side of the inclined disk. These results underline the importance of considering both the shadowing effect from the inner disk and the surface geometry of the observed reflecting disk in the analysis and interpretation of observational data.
Revisiting the multi-planetary system of the nearby star HD 20794
Authors: Nari N. , Dumusque X. , Hara N. C. , Suárez Mascareño A. , Cretignier M. , González Hernández J. I. , Stefanov A. K. , Passegger V. M. , Rebolo R. , Pepe F. , Santos N. C. , Cristiani S. , Faria J. P. , Figueira P. , Sozzetti A. , Zapatero Osorio M. R. , Adibekyan V. , Alibert Y. , Allende Prieto C. , Bouchy F. , Benatti S. , Castro-González A. , D’Odorico V. , Damasso M. , Delisle J. B. , Di Marcantonio P. , Ehrenreich D. , Génova-Santos R. , Hobson M. J. , Lavie B. , Lillo-Box J. , Lo Curto G. , Lovis C. , A. P. Martins C. J. , Mehner A. , Micela G. , Molaro P. , Mordasini C. , Nunes N. , Palle E. , Quanz S.P. , Ségransan D. , Silva A. M. , Sousa S. G. , Udry S. , Unger N. , Venturini J. 
Published: November 2024

Context. Close-by Earth analogs and super-Earths are of primary importance because they will be preferential targets for the next generation of direct imaging instruments. Bright and close-by G-to-M type stars are preferential targets in radial velocity surveys to find Earth analogs. Their brightness allows us to achieve the best precision on RV measurements and search for signals with amplitudes of less than 1 m s−1.
Aims. We present an analysis of the RV data of the star HD 20794, a target whose planetary system has been extensively debated in the literature. The broad time span of the observations makes it possible to find planets with signal semi-amplitudes below 1 m s−1 in the habitable zone.
Methods. We analyzed RV datasets spanning more than 20 years. We monitored the system with ESPRESSO. We joined ESPRESSO data with the HARPS data, including archival data and new measurements from a recent program. We applied the post-processing pipeline YARARA to HARPS data to correct systematics, improve the quality of RV measurements, and mitigate the impact of stellar activity.
Results. We confirm the presence of three planets, with periods of 18.3142 ± 0.0022 d, 89.68 ± 0.10 d, and 647.6−2.7+2.5 d, along with masses of 2.15 ± 0.17 M⊕, 2.98 ± 0.29 M⊕, and 5.82 ± 0.57 M⊕ respectively. For the outer planet, we find an eccentricity of 0.45−0.11+0.10, whereas the inner planets are compatible with circular orbits. The latter is likely to be a rocky planet in the habitable zone of HD 20794. From the analysis of activity indicators, we find evidence of a magnetic cycle with a period of ~3000 d, along with evidence pointing to a rotation period of ~39 d.
Conclusions. We have determined the presence of a system of three planets orbiting the solar-type star HD 20794. This star is bright (V=4.34 mag) and close (d = 6.04 pc), and HD 20794 d resides in the stellar habitable zone, making this system a high-priority target for future atmospheric characterization with direct imaging facilities.
RETRACTED: Speckle-based adaptation concept of a compensation system for free-space optical communications
Authors: Al-Juboori Haider 
Published: October 2024

This article has been retracted because it substantially reflects a significant part of the content and some figures of the following original PhD thesis, without reference to it: “Advanced adaptive compensation system for free-space optical communications” by Carlos E. Carrizo, DOI: 10.5821/dissertation-2117-168867
The author admits that he inadvertently omitted to properly cite this reference, neither asked authorization for use. He sincerely apologizes for the oversight.
Retraction approved by the Editor and the Publisher on February 6, 2025.
Distal Aortic Events following Emergent Aortic Repair for Acute DeBakey Type I Aortic Dissection: An Inverse Probability of Treatment Weighting Analysis
Authors: Miyahara Shunsuke , Uchino Gaku , Nomura Yoshikatsu , Tanaka Hiroshi , Murakami Hirohisa 
Published: November 2024

Abstract
Objective The goal of this study is to examine early and midterm results after surgical treatment of acute DeBakey type I aortic dissection (AIAD) and the effect of the range of aortic arch replacement on overall survival and prevention of distal aortic events.
Methods Between March 2002 and July 2020, a total of 374 AIAD aortic repairs were reviewed. A total of 154 (41.2%) patients had total arch replacement (TAR), whereas 220 (58.8%) had hemi- or partial arch replacement (PAR).
Results Operative mortality did not show a significant difference (7.7% in PAR, 13.0% in TAR, p = 0.096). Survival at 5 years showed no difference (77.8% in TAR, 72.6% in PAR, p = 0.14). Freedom from reoperations and reinterventions, as well as composite aortic events in the distal aorta, were comparable across groups (p = 0.21, 0.84, and 0.91, respectively). The inverse probability of treatment weighting-adjusted model displayed higher 5-year freedom from reoperations and aortic events in the TAR group (p = 0.029 and 0.054, respectively).
Conclusion The extent of arch replacement is determined based on the patient background, making it difficult to compare the superiority of both surgical methods. However, TAR for appropriately selected patients may provide the benefit of avoiding aortic events in the long term.
Metamaterial unipolar quantum optoelectronics for mid-infrared free-space optics
Authors: Bonazzi T. , Dely H. , Didier P. , Gacemi D. , Fix B. , Beck M. , Faist J. , Harouri A. , Sagnes I. , Grillot F. , Vasanelli A. , Sirtori C. 
Published: November 2024

Free-space optical communications in the mid-infrared transparency windows (4–5 and 8–14 μm wavelength regions) is emerging as a viable solution for high bitrate data transmission. Unipolar quantum optoelectronics is the technology of choice for data communication in this wavelength region, thanks to the high frequency response of detectors and modulators. In this work, it is demonstrated that the performances of these devices can be substantially enhanced by embedding them into metamaterials. It is also shown that metamaterials have to be engineered differently in detectors than in modulators, as the role of light–matter interaction must be tuned adequately in the two devices. Metamaterial-enhanced performances allow the realization of data transmission with a record rate of 68 Gbit/s, while ensuring robustness and consistency, as it should be for real-world applications. These findings underscore the promising role of metamaterial-enhanced unipolar devices in advancing free-space optical communication systems.
Mechanical properties of (Ni, Fe)Cr2O4 polycrystal spinels studied by molecular dynamics simulations
Authors: Van Brutzel L. , Chartier A. 
Published: November 2024

The elastic moduli and mechanical properties at the onset of crack in nanocrystalline and nanoporous (Ni, Fe)Cr2O4 compounds with a spinel structure are investigated by molecular dynamics simulations. The polycrystalline structures generated contain nanograins from 2.5 to 30 nm in diameter. These structures are representative of the internal corrosion layer in nickel-based alloys. These simulations enabled us to establish the evolution of elastic moduli as a function of the composition, porosity, and grain size of the polycrystals. From this evolution, the initial database for the elastic properties of corrosion layers based on von Bertalanffy growth functions was determined. The onset of crack in polycrystals is also investigated via uniaxial tensile and shear deformation. Under shear deformation, flow stress as a function of grain size follows normal and inverse Hall–Petch regimes. The regime change occurs for grain sizes around 10 nm. For grain sizes under this threshold, shear banding involving collective translation and rotation of nanograins dominates the plastic deformation. For grain sizes greater than 10 nm, phase transition inside grains from a spinel to a post-spinel-like structure is observed as well. In that case, phase transition dominates the plastic deformation. Under uniaxial tensile deformation, intergranular decohesion occurs. The general law as a function of grain size for toughness, which is the material’s capacity to absorb elastic and plastic energy prior to failure, is also established.
Understanding melting behavior of aluminum clusters using machine learned deep neural network potential energy surfaces
Authors: Kumar Amit , Nagare Balasaheb J. , Sharma Raman , Kanhere Dilip G. 
Published: November 2024

Deep neural network-based deep potentials (DP), developed by Tuo et al., have been used to compute the thermodynamic properties of free aluminum clusters with accuracy close to that of density functional theory. Although Jarrold and collaborators have reported extensive experimental measurements on the melting temperatures and heat capacities of free aluminum clusters, no reports exist for finite-temperature ab initio simulations on larger clusters (N &gt; 55 atoms). We report the heat capacities and melting temperatures for 32 clusters in the size range of 48–342 atoms, computed using the multiple histogram technique. Extensive molecular dynamics (MD) simulations at twenty four temperatures have been performed for all the clusters. Our results are in very good agreement with the experimental melting temperatures for 19 clusters. Except for a few sizes, the interesting features in the heat capacities have been reproduced. To gain insight into the striking features reported in the experiments, we used structural and dynamical descriptors such as temperature-dependent mean squared displacements and the Lindemann index. Bimodal features observed in Al116 and the weak shoulder seen in Al52 are attributed to solid–solid structural transitions. In confirmation of the earlier reports, we observe that the behavior of the heat capacities is significantly influenced by the nature of the ground state geometries. Our findings show that the sharp drop in the melting temperature of the 56-atom cluster is a consequence of the change in the geometry of Al55. Mulliken population analysis of Al55 reveals that the charge-induced local electric field is responsible for the strong bonding between core and surface atoms, leading to the higher melting temperature. Our calculations do not support the lower melting temperature observed in experimental studies of Al69. Our results indicate that Al48 is in a liquid state above 600 K and does not support the high melting temperature reported in the experiment. It turns out that the accuracy of the DP model by Tuo et al. is not reliable for MD simulations beyond 750 K. We also report low-lying equilibrium geometries and thermodynamics of 11 larger clusters (N = 147–342) that have not been previously reported, and the melting temperatures of these clusters are in good agreement with the experimental ones.
Modified Debye–Hückel–Onsager theory for electrical conductivity in aqueous electrolyte solutions: Account of ionic charge nonlocality
Authors: Kalikin Nikolai N. , Budkov Yury A. 
Published: November 2024

This paper presents a mean field theory of electrolyte solutions, extending the classical Debye–Hückel–Onsager theory to provide a detailed description of the electrical conductivity in strong electrolyte solutions. The theory systematically incorporates the effects of ion specificity, such as steric interactions, hydration of ions, and their spatial charge distributions, into the mean-field framework. This allows for the calculation of ion mobility and electrical conductivity, while accounting for relaxation and hydrodynamic phenomena. At low concentrations, the model reproduces the well-known Kohlrausch’s limiting law. Using the exponential (Slater-type) charge distribution function for solvated ions, we demonstrate that experimental data on the electrical conductivity of aqueous 1:1, 2:1, and 3:1 electrolyte solutions can be approximated over a broad concentration range by adjusting a single free parameter representing the spatial scale of the nonlocal ion charge distribution. Using the fitted value of this parameter at 298.15 K, we obtain good agreement with the available experimental data when calculating electrical conductivity across different temperatures. We also analyze the effects of temperature and electrolyte concentration on the relaxation and electrophoretic contributions to total electrical conductivity, explaining the underlying physical mechanisms responsible for the observed behavior.
Tunable kHz distributed feedback fiber laser fabricated in 3D-printed glass
Authors: Maniewski Pawel , Flint Alex I. , Bannerman Rex H. S. , Lee Timothy , Beresna Martynas 
Published: November 2024

For short sections of fiber tailored to a specific application, fast laser-based manufacturing techniques can be considered as an attractive alternative to the often-cumbersome traditional manufacturing routes. With the use of high-power lasers, localized hot zones that are necessary for glass making can be obtained rapidly. For instance, laser-powder-deposition enables rapid fabrication of short, high gain fibers used in, e.g., distributed feedback fiber lasers (DFFLs). DFFLs offer sought after performance suitable for a broad range of applications in modern photonics, i.e., superior stability and narrower, single-frequency linewidth compared to conventional fiber lasers. Tunable, narrow laser sources with output in an eye-safe spectrum are desired for sensing, signal multiplexing, LIDAR systems, quantum applications, etc. In this work, we present DFFL obtained using laser-powder-deposition made Er-doped silica fiber. Milliwatt level, narrow line lasing (&lt;704 kHz, equipment limited) was obtained using a phase-shifted grating written in 16 mm long fiber. The backward slope efficiency was as high as 24% when pumping at 976 nm. The results presented in this work showcase new possibilities in fiber fabrication that were unlocked through laser-assisted additive manufacturing. This fiber laser sets the stage for the future of rapid fabrication of advanced fiber devices through unconventional manufacturing routes.
Exciton dynamics in CsPbBr3 single crystal: LT splitting energy, exciton–polariton dispersion, and biexciton binding energy
Authors: Shimosako Naoki , Kumamoto Mizuki , Muroga Yui , Liu Zihao , Sotome Masato , Kondo Takashi , Kunugita Hideyuki , Ema Kazuhiro 
Published: November 2024

Metal halide perovskite materials (MHPs) are promising for several applications due to their exceptional properties. Understanding excitonic properties is essential for exploiting these materials. For this purpose, we focus on CsPbBr3 single crystals, which have higher crystal quality, are more stable, and have no Rashba effect at low temperatures compared to other 3D MHPs. We have estimated exciton energy positions, longitudinal-transverse splitting energy, and damping energy using low-temperature reflection spectra. Under high excitation intensity, two biexciton emissions (M-emission) and exciton–exciton scattering emission (P-emission) were observed. We assign the two M-emissions to the emission to the states of longitudinal and transverse excitons, i.e., ML and MT emissions. From the energy position of the MT emission, the biexciton binding energy has been estimated to be ∼2 meV. By analyzing P-emission obtained from the back side of the sample, we have estimated the exciton binding energy to be 17.8–23.7 meV. This estimation minimizes the influence of the wavenumber distribution in the scattering process. In addition, time-resolved transmittance measurements using pulsed white light have revealed the group velocity dispersion. Comparing experimental results with theoretical calculations using the Lorentz model clarifies that exciton dynamics in CsPbBr3 can be described with a simple Lorentz model. These insights enhance the understanding of exciton behavior and support the development of exciton-based devices using MHPs.
Impact of chlorine substitution on valence orbitals and ionization dynamics in 3-chloropyridine: Insights from high-resolution vacuum ultraviolet mass-analyzed threshold ionization study
Authors: Park Sung Man , Kim Hyojung , Kwon Chan Ho 
Published: November 2024

In this study, the effects of chlorine substitution on the valence orbitals and electronic states of 3-chloropyridine (3-CP) were investigated utilizing high-resolution vacuum ultraviolet mass-analyzed threshold ionization (VUV-MATI) spectroscopy and computational methods. High-quality vibrational spectra were obtained from the VUV-MATI spectra of 3-CP isotopomers (35Cl and 37Cl), revealing high-quality vibrational spectra for the lowest cationic states. The adiabatic ionization energies (AIEs) of these isotopomers were accurately determined, providing detailed information about the electronic structure and ionization dynamics. Intense spectra peaks were linked with the D1 excited state of the 3-CP cation, with vibronic transitions in this state closely matching those predicted by Franck–Condon simulations. This provided insights into the cationic structure and the roles of the highest occupied molecular orbital (HOMO) and the HOMO-1. The HOMO was primarily a π orbital of the pyridine ring, while the HOMO-1 consisted of nonbonding orbitals. The AIEs suggested that meta-chlorine substitution stabilizes nonbonding orbitals less effectively than ortho substitution, indicating closely spaced electronic states in the 3-CP cation. Minor discrepancies in vibrational frequencies and intensities, particularly above 800 cm−1, suggested the presence of vibronic coupling, warranting further investigation. Overall, this study provided a comprehensive understanding of the vibronic and ionization properties of 3-CP, emphasizing the influence of the position of the chlorine substitution on molecular orbitals and the value of advanced theoretical and experimental approaches for analyzing the vibrational spectra of complex molecules.