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Mathematical beauty and Palladian architecture:Measuring and comparing visual complexity and diversity

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Frontiers of Architectural Research 2024年第4期13卷 729-740页

作者： Ju Hyun Lee michael J.Ostwald School of Built Environment Faculty of ArtsDesign&ArchitectureThe University of New South WalesSydneyNSW 2052Australia

Palladio’s design principles,including proportion and harmony,have often been associated with mathematical definitions of ***,the geometric and semantic properties of his fac¸ades have rarely been analysed in a holistic *** is little evidence of how mathematical beauty may be embodied in his *** research investigates complexity(fractal dimension or d)and diversity(perplexity or PP)as aesthetic indices,aiming to capture distinct characteristics of Palladian *** d and PP values of 22 Palladian villa fac¸ades are measured and analysed,before being compared with those of three Renaissance facades by Sebastiano *** combination of d and PP captures the geometric and semantic aesthetic qualities of architectural ***,the developed scatter plot of d and PP results supports the identification of four distinct aesthetic types of Palladian fac¸ade *** novel combination of d and PP measures contributes to a better understanding of one definition of the mathematical beauty of architecture,wherein“the whole is other than the sum of the parts”in compositional terms(a famous Gestalt principle).Specifically,this research provides new mathematical insights into the visual character of Palladian architecture and compares two important measures thereof.

关键词： Palladian architecture Complexity diversity Mathematical beauty Perplexity Fac¸ade design

Spark plasma sintering of tungsten-based WTaVCr refractory high entropy alloys for nuclear fusion applications

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 146-154页

作者： Yongchul Yoo Xiang Zhang Fei Wang Xin Chen Xing-Zhong Li michael Nastasi Bai Cui department of Mechanical&Materials Engineering University of Nebraska-LincolnLincolnNE 68588USA Nebraska Center for Materials and Nanoscience University of Nebraska-LincolnLincolnNE 68588USA department of Nuclear Engineering Texas A&M UniversityCollege StationTX 77843USA

W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a powder metallurgy process combining mechanical alloying and spark plasma sintering (SPS). The SPSed samples contained two phases, in which the matrix is RHEA with a body-centered cubic structure, while the oxide phase was most likely Ta2VO6through a combined analysis of X-ray diffraction (XRd),energy-dispersive spectroscopy (EdS), and selected area electron diffraction (SAEd). The higher oxygen affinity of Ta and V may explain the preferential formation of their oxide phases based on thermodynamic calculations. Electron backscatter diffraction (EBSd) revealed an average grain size of 6.2μm. WTaVCr RHEA showed a peak compressive strength of 2997 MPa at room temperature and much higher micro-and nano-hardness than W and other W-based RHEAs in the literature. Their high Rockwell hardness can be retained to at least 1000°C.

关键词： refractory high entropy alloy plasma-facing material fusion reactor spark plasma sintering

direct Pointwise Comparison of FE Predictions to StereodIC Measurements:developments and Validation Using double Edge-Notched Tensile Specimen

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1263-1298页

作者： Troy Myers michael A.Sutton Hubert Schreier Alistair Tofts Sreehari Rajan Kattil department of Mechanical Engineering University of South CarolinaColumbiaSC29208USA Correlated Solutions Incorporated 121 Dutchman BlvdColumbiaSC29063USA

To compare finite element analysis(FEA)predictions and stereovision digital image correlation(StereodIC)strain measurements at the same spatial positions throughout a region of interest,a field comparison procedure is *** procedure includes(a)conversion of the finite element data into a triangular mesh,(b)selection of a common coordinate system,(c)determination of the rigid body transformation to place both measurements and FEA data in the same system and(d)interpolation of the FEA nodal information to the same spatial locations as the StereodIC measurements using barycentric *** an aluminum Al-6061 double edge notched tensile specimen,FEA results are obtained using both the von Mises isotropic yield criterion and Hill’s quadratic anisotropic yield criterion,with the unknown Hill model parameters determined using full-field specimen strain measurements for the nominally plane stress *** Hill’s quadratic anisotropic yield criterion,the point-by-point comparison of experimentally based full-field strains and stresses to finite element predictions are shown to be in excellent agreement,confirming the effectiveness of the field comparison process.

关键词： StereodIC spatial co-registration data transformation finite element simulations point-wise comparison of measurements and FEA predictions double edge notch specimen model validation

Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter

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Earth and Planetary Physics 2024年第1期8卷 173-183页

作者： Hyangpyo Kim Hyunju K.Connor Jaewoong Jung Brian M.Walsh david Sibeck Kip d.Kuntz Frederick S.Porter Catriana K.Paw U Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura michael Collier Space Research Institute Austrian Academy of Sciences8042 GrazAustria Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA National Aeronautics and Space Administration(NASA)Goddard Space Flight Center GreenbeltMaryland 20771USA Astronomy department University of Maryland College ParkCollege ParkMaryland 20742USA Center for Space Physics Boston UniversityBostonMassachusetts 02215USA department of Physics and Astronomy Johns Hopkins UniversityBaltimoreMaryland 21218USA Howard University WashingtonDC 20059USA

The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind *** suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray *** this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is *** assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause *** create synthetic soft X-ray images by using the Open Geospace General Circulation Model(OpenGGCM)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson *** then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea *** the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground *** method estimates RS with an accuracy ofd density exceeds>10 *** accuracy improves for greater solar wind densities and during southward interplanetary magnetic *** method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field ***,the technique will enable quantitative analysis of the magnetopause motion and help reveal the daysi

关键词： soft X-ray magnetopause reconnection low-pass filter LEXI SMILE

A three-dimensional feature extraction-based method for coal cleat characterization using X-ray μCT and its application to a Bowen Basin coal specimen

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 153-166页

作者： Yulai Zhang Matthew Tsang Mark Knackstedt michael Turner Shane Latham Euan Macaulay Rhys Pitchers ARC Training Centre for M3d Innovation Research School of PhysicsAustralian National UniversityCanberraACT2601Australia department of Materials Physics Research School of PhysicsAustralian National UniversityCanberraACT2601Australia Anglo American Steelmaking Coal BrisbaneQLD4000Australia SCT Operations Pty Ltd. WollongongNSW2500Australia

Cleats are the dominant micro-fracture network controlling the macro-mechanical behavior of *** understanding of the spatial characteristics of cleat networks is therefore important to the coal mining *** fracture networks(dFNs)are increasingly used in engineering analyses to spatially model fractures at various *** reliability of coal dFNs largely depends on the confidence in the input cleat *** of these parameters can be made from image-based three-dimensional(3d)characterization of coal cleats using X-ray micro-computed tomography(m CT).One key step in this process,after cleat extraction,is the separation of individual cleats,without which the cleats are a connected network and statistics for different cleat sets cannot be *** this paper,a feature extraction-based image processing method is introduced to identify and separate distinct cleat groups from 3d X-ray m CT ***(filters)representing explicit cleat features of coal are built and cleat separation is successfully achieved by convolutional operations on 3d coal *** new method is applied to a coal specimen with 80 mm in diameter and 100 mm in length acquired from an Anglo American Steelmaking Coal mine in the Bowen Basin,Queensland,*** is demonstrated that the new method produces reliable cleat separation capable of defining individual cleats and preserving 3d topology after ***-parallel fractures are also identified and separated,which has his-torically been challenging to delineate and rarely reported.A variety of cleat/fracture statistics is measured which not only can quantitatively characterize the cleat/fracture system but also can be used for dFN ***,variability and heterogeneity with respect to the core axis are *** heterogeneity is observed and suggests that the representative elementary volume(REV)of the cleat groups for engineering purposes may be a complex problem requ

关键词： Cleat separation Cleat statistics Feature extraction discrete fracture network(dFN)modeling

Review of Moirésuperconductivity and application of the Roeser-Huber formula

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Superconductivity 2024年第1期9卷 9-28页

作者： michael R.Koblischka Anjela Koblischka-Veneva Institute of Experimental Physics Saarland UniversityCampus C 6366123 SaarbrückenGermany

Moirésuperconductivity represents a new class of superconducting materials since the discovery of superconductivity in magic‐angle(1.1°)twisted bi‐layer graphene(MATBG),forming a Moirélattice with a much bigger crystal parameter as the original lattice constant of ***,experimentally changing the Moirétwist angle,0.93°≤Θ≤1.27,leads to a variation of the superconducting properties and enables a new way of engineering 2d superconducting *** of the robust superconducting state of MATBG as function of charge carrier density,temperature and applied magnetic fields are *** influence of the top/bottom hexagonal boron nitride layer thickness on the superconducting properties of MATBG was also demonstrated in the *** all fabricated MATBG devices,changing of the charge carrier density leads to the appearance of insulating,metallic and even ferromagnetic states,which separate several superconducting domes in the phase diagram(longitudinal resistance,Rxx,as function of temperature T and charge carrier density,n).Further works have considered MATBG combined with WSe2‐layers,twisted bi‐layer WSe2,magic‐angle trilayer graphene(MATTG),and most recently,four‐layer(MAT4G)and five‐layer(MAT5G)*** differences between the layered,cuprate high‐Tc superconductors and the Moirésuperconductors are compiled *** collected information is then used to apply the Roeser‐Huber formalism to Moiré‐type superconductivity to calculate the superconducting transition temperature,Tc,using only information of the Moirélattice and the electronic *** account for the different charge carrier densities in the experimental data sets and the low charge carrier mass demands that a new parameterηmust be introduced to the Roeser‐Huber formalism to enable the description of several superconducting domes found in the phase diagram for a given Moiré*** so,the calculated data fit well to the correlation curve defined within the Roeser‐Hube

关键词： MoiréSuperconductors Twisted bilayer graphene Magic angle Multilayer graphene stacks Superconducting transition temperature Roeser‐Huber formalism

dietary xylo‑oligosaccharides and arabinoxylans improved growth efficiency by reducing gut epithelial cell turnover in broiler chickens

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1325-1335页

作者： Carla Castro Shahram Niknafs Gemma Gonzalez‑Ortiz Xinle Tan michael R.Bedford Eugeni Roura Centre for Nutrition and Food Sciences Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandSt LuciaQLD 4072Australia AB Vista MarlboroughWiltshire SN84ANUK

Background One of the main roles of the intestinal mucosa is to protect against environmental ***-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in *** may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier *** aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction(AXRF)supplementation on gut func-tion and epithelial integrity in broiler *** A total of 128 broiler chickens(Ross 308)were assigned into one of two different dietary treatments for a period of 42 d:1)control diet consisting of a corn/soybean meal-based diet;or 2)a control diet supplemented with 0.5%XOS and 1%*** treatment was randomly distributed across 8 pens(n=8)with 8 chickens *** intake and body weight were recorded *** d 42,one male chicken per pen was selected based on aver-age weight and euthanized,jejunum samples were collected for proteomics *** dietary XOS/AXRF supplementation improved feed efficiency(Pd 1 to 42 compared to the con-trol *** analysis was used to understand the mechanism of improved efficiency uncovering 346 dif-ferentially abundant proteins(dAP)(Padjd chickens compared to the non-supplemented *** the jejunum,the dAP translated into decreased ATP production indicating lower energy expenditure by the tissue(e.g.,inhibition of glycolysis and tricarboxylic acid cycle pathways).In addition,dAP were associated with decreased epithelial cell differentiation,and migration by reducing the actin polymerization ***-ting the two main pathways together,XOS/AXRF supplementation may decrease around 19%the energy required for the maintenance of the gastrointestinal *** dietary XOS/AXRF supplementation improved gr

关键词： Actin Arabinoxylans Broiler Cell turnover Energy metabolism Jejunum Xylo-oligosaccharides

detailed characterization of kHz-rate laser-driven fusion at a thin liquid sheet with a neutron detection suite

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High Power Laser Science and Engineering 2024年第1期12卷 13-23页

作者： Benjamin M.Knight Connor M.Gautam Colton R.Stoner Bryan V.Egner Joseph R.Smith Chris M.Orban Juan J.Manfredi Kyle d.Frische michael L.dexter Enam A.Chowdhury Anil K.Patnaik department of Engineering Physics Air Force Institute of TechnologyWPAFBOHUSA Physics department Marietta CollegeMariettaOHUSA department of Physics The Ohio State UniversityColumbusOHUSA department of Materials Science and Engineering and Department of Electrical and Computer ScienceThe Ohio State UniversityColumbusOHUSA Intense Energy Solutions LLCPlain CityOHUSA

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mJ, 40 fs laser pulses on a thin(<1 μm) d_2O liquid sheet employing a measurement suite. At relativistic inte... 详细信息

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mJ, 40 fs laser pulses on a thin(d_2O liquid sheet employing a measurement suite. At relativistic intensity(~ 5 × 10^(18)W/cm^(2))and high repetition rate(1 kHz), the system produces deuterium±deuterium(d-d) fusion, allowing for consistent neutron generation. Evidence of d-d fusion neutron production is verified by a measurement suite with three independent detection systems: an EJ-309 organic scintillator with pulse-shape discrimination, a ~3He proportional counter and a set of 36 bubble detectors. Time-of-flight analysis of the scintillator data shows the energy of the produced neutrons to be consistent with 2.45 MeV. Particle-in-cell simulations using the WarpX code support significant neutron production from d-d fusion events in the laser±target interaction region. This high-repetition-rate laser-driven neutron source could provide a low-cost, on-demand test bed for radiation hardening and imaging applications.

关键词： high-repetition-rate laser-driven fusion laser-plasma interaction liquid target neutron detectors

Are there sex-based disparities in cataract surgery?

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： Matthew d.Geiger Anne M.Lynch Alan G.Palestine Nathan C.Grove Karen L.Christopher Richard S.davidson michael J.Taravella Naresh Mandava Jennifer L.Patnaik department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIM:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado School of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BCVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).Conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadjusted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adjustment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%CI=0.7-0.9,P=0.0005).The BCVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of Snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes