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关键词： 2-design   Flag-transitive   Automorphism group   Almost simple group  

摘要： Let D = (P, B) be a 2-(v, k, ?) design admitting a flag-transitive automorphism group G with gcd(v-1, k-1) = 3 or 4. We showed in [28, Theorems 1.2 and 1.3] that G is point-primitive and of affine or almost simple type, except when D is a unique 2-(25, 4, 12) or 2-(25, 4, 18) design. Let Soc(G) be a nonabelian simple group. In this paper, we prove that either G is 2-transitive or D is one of nine designs with known parameters. As a main result, we complete the classification of symmetric designs D. (c) 2026 Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Sulfuric acid   Liquid-liquid equilibrium   NRTL   Alcohols  

摘要： Liquid-liquid equilibrium (LLE) data were obtained for water + sulfuric acid + {1-butanol, isopentanol, 1-pentanol, or 1-heptanol} ternary systems at temperatures of 298.2 K and 323.2 K under atmospheric pressure (P approximate to 101.9 kPa). The immiscibility regions were experimentally identified through binodal curves using the cloud point method. Tie-line data were determined through direct sulfuric acid composition measurements and mass fraction calibration curves. Based on these data, distribution coefficients, alcohol selectivity and extraction percentage were calculated to evaluate the influence of different alcohols and temperature on sulfuric acid separation potential. Experimental LLE data were correlated using the Non-Random Two-Liquid model, presenting a root-mean-square deviation equal to 1.1768 % for all studied systems. The model also allowed the estimation of binodal curves and plait points. These results contribute to the understanding and optimization of solvent extraction processes involving sulfuric acid recovery in industrial water streams.

关键词： Tm fiber laser   High power fiber laser   Laser oscillator   Eye-safe wavelength  

摘要： We report a continuous-wave thulium (Tm)-doped fiber laser oscillator with >1 kW output power operating at 1940 nm under the optimized cooling condition. Using a water calorimetry method, the temperature increases and its impact on output power were experimentally investigated, confirming good agreement with theoretical predictions. To mitigate thermal effects on laser performance, a bi-directional pumping configuration was implemented, theoretically reducing the maximum Tm fiber temperature by similar to 40% compared to forward pumping. Under the optimized cooling condition, the Tm fiber laser yielded a maximum output power of 1032 W for an incident pump power of 1785 W, corresponding to a slope efficiency of 58.5%. A near-diffraction-limited beam quality was maintained at all power levels, along with excellent output stability.

关键词： 1-embeddable graph   torus   connectivity   perfect matching  

摘要： In this paper, we discuss optimal 1-toroidal graphs (abbreviated as O1TG which are drawn on the torus so that every edge crosses another edge at most once, and has n vertices and exactly 4n edges. We first consider connectivity of O1TGs, and give the characterization of O1TGs having connectivity exactly k for each k is an element of {4, 5, 6, 8}. In our argument, we also show that there exists no O1TG having connectivity exactly 7. Furthermore, using the result above, we discuss extendability of matchings, and give the characterization of 1-, 2-and 3-extendable O1TGs in turn.

关键词： Urban microclimate   Data homogenization   Geostatistical interpolation   Satellite-gauge integration   Variogram modeling   Ensemble regression  

摘要： This study presents the development of a 1-km resolution, daily gridded rainfall dataset for Greater Kuala Lumpur, Malaysia, covering the period 1975-2024. The study employed a robust multi-stage framework that included multivariate imputation with MICE and Random Forests, homogenization using the Standard Normal Homogeneity Test (SNHT and interpolation with auxiliary variables, including satellite-derived rainfall Global Satellite Mapping of Precipitation (GSMaP land surface temperature (LST and coastal proximity. Daily rainfall surfaces were generated using an automated external drift kriging framework that integrates the most relevant auxiliary variables as spatial predictors, featuring an adaptive variogram-fitting routine and a half-cell-shifted grid-alignment strategy that ensures stable interpolation and eliminates boundary-induced striping artifacts even under sparse gauge networks. Quantitative evaluation demonstrated high imputation accuracy, with Kling-Gupta Efficiency (KGE) reaching 0.94, R-2 values averaging 0.90, and percent bias (PBIAS) within +/- 5%. Homogenization corrected statistically significant breakpoints and eliminated artificial trends caused by station relocations and instrumentation changes. The final gridded product showed excellent spatial accuracy, with cross-validation R-2 values exceeding 0.97, KGE between 0.90 and 0.99, normalized RMSE (NRMSE) ranging from 0.05 to 0.15, and minimal bias across all years. Correlation analysis indicated that GSMaP (rho = 0.47) and LST (rho = 0.39) were more effective covariates than elevation (rho = -0.09) in the tropical urban setting. The dataset accurately reproduced key rainfall characteristics, including daily distributions (R-2 = 0.99 for <= 30 mm and 0.92 for >30 mm seasonal cycles (monthly deviation <10 mm and annual totals (errors within +/- 50-100 mm or <5%). It also preserved temporal trends and extreme-event frequencies, effectively capturing the observed increase in the frequency of heavy

关键词： Fiber combiner   Infrared   Chalcogenide glasses   Beam quality  

摘要： Fiber combiners (FCs which fuse multiple input fibers into a common output port, offer a strategic approach to scaling laser power and expanding spectral coverage, especially in the mid- and long-wave infrared (MWIR/LWIR) bands where individual laser performance is often limited. Chalcogenide glasses serve as ideal materials for such combiners due to their broad infrared transparency and superior thermal stability. However, fabricating FCs capable of withstanding high laser power while maintaining high beam quality remains challenging, particularly when targeting wavelengths beyond 8 mu m. Here, we present the first demonstration of a high-beam-quality 4 & times;1 fiber combiner based on Ge-As-Se glass, designed for MWIR/LWIR laser combination. The device integrates four few-mode input fibers (50 mu m core) into a multimode output fiber (150 mu m core) via an optimized taper geometry (transition region length L-t= similar to 10 mm, taper ratio R = similar to 4.6). The fabricated FC had a total length of similar to 60 cm. At 8.3 mu m, the combiner achieved a port transmission efficiency of 81.6% and maintained an output beam quality of M-2 = 3.62 under four-port excitation. Power combining at 2.1 mu m yielded 6.5 W from four 3.0-W inputs, corresponding to a power-combining efficiency of 82.7%. Furthermore, the combiner successfully synthesized a broadband spectrum by integrating discrete laser lines at 3.2, 4.6, 4.9, and 8.3 mu m. These results establish the few-mode Ge-As-Se fiber combiner as a promising platform that delivers both high-power combination and high beam quality across the MWIR and LWIR bands for advanced infrared photonic systems.

关键词： malignant melanoma   metastasis   neurofibromatosis type 1   von Recklinghausen's disease   autopsy   endoscopic image  

关键词： poverty reduction   decent work and economic growth   sustainable development   dynamic RDM-DDF DEA model  

摘要： Addressing regional disparities while pursuing sustainable development has become a critical policy challenge. This study develops a meta parallel two-stage dynamic range directional measure (RDM) directional distance function (DDF) data envelopment analysis (DEA) model to evaluate the efficiency of poverty reduction (SDG 1) and decent work and economic growth (SDG 8) across 30 provinces in China. Given uneven regional development, the provinces are grouped into eastern, central, and western regions, and kernel density estimation is employed to examine the spatial and temporal evolution of efficiency. The results indicate that 1) The overall efficiency is moderate, with an average score of 0.67, highest in the eastern region, followed by the western, and lowest in the central region. (2) The efficiency of SDG 8 (0.93) significantly exceeds that of SDG 1 (0.87 while the regional ranking remains consistent with the overall efficiency. (3) The technology gap among the three regions shows dynamic changes: the western region has overtaken the eastern region to become the most advanced. In contrast, the central region continues to lag, and its gap with the other regions is steadily widening.

关键词： 3D-printed   Hybrid composite   Indirect partial restoration   Digital workflow   Onlays  

摘要： Patients: A 22-year-old female patient presented with a lower right first molar exhibiting an extensive carious lesion beneath an old direct resin composite restoration. Radiographic evaluation revealed pulpal involvement with a periapical infection, accompanied by grade II mobility and a circumferential probing depth of <3 mm. The compromised molar rehabilitation was carried out using a multichromatic 3D-printed onlay. A fully digital workflow was employed, enabling the completion of the procedure in a single clinical session. Following endodontic and restorative treatments, intraoral scans were acquired using a Trios5 scanner. The restoration was digitally designed and 3D printed from STL files using the DWS Systems Dfab printer. The hybrid composite onlay was adhesively luted using a universal self-adhesive resin cement (Panavia SA, Kuraray). Clinical evaluations at 6 months and 1 year demonstrated favorable outcomes, with high patient satisfaction. Discussion: 3D printing represents a digital evolution in the fabrication of dental restorations, introducing an additive manufacturing approach distinct from the subtractive processes used in traditional CAD/CAM systems. In cases of severely compromised teeth, 3D-printed, adhesively bonded partial restorations represent a viable treatment option. The hybrid composite used in this study demonstrated favorable clinical and esthetic performance, enabling minimally invasive preparations while preserving sound tooth structure. Conclusions: Chairside 3D printing technology presents an alternative approach for the fabrication of indirect composite restorations in posterior teeth. Although 3D printing is not yet widely adopted in restorative dentistry, its versatility may offer significant advantages for both clinicians and patients in the production of indirect partial restorations.

关键词： Green's function   Fourier transformation   Generalized nonlinear wave equation   Nonlocal partial derivative formalism  

摘要： A generalized (2+1)-dimensional nonlinear wave equation is investigated within the framework of di-dressing method. By complexifying the temporal and spatial variables, a (4+2)-dimensional extension of this equation is derived. Through the introduction of two independent variables, the higher-dimensional equation is reduced to a generalized (3+1)-dimensional form. Based on this formulation, the di-dressing method is employed to construct solutions. The results provide an effective approach for studying higher-dimensional nonlinear wave equations and further demonstrate the applicability of the di-formalism in multidimensional integrable systems.