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Topologically Correct Intersection Curves of Two Trimmed Quadrics with Tolerance Control

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Journal of Systems Science & Complexity 2024年第5期37卷 2207-2239页

作者： SHAO Wenbing CHEN Falai department of Mathematics University of Science and Technology of China

Surface/surface intersection is a fundamental problem in Compute Aided Design and Geometric Modeling since it is essential to solid modeling, numerically controlled machining, feature recognition, computer animation, etc. In practical applications, quadric surfaces, which are the most basic type of surfaces, are typically bounded surfaces trimmed by a sequence of planes. In this paper,a robust algorithm is proposed for computing the intersection curve segments of two trimmed quadrics based on the parametric representation of the intersection curves of two quadrics. The proposed algorithm guarantees correct topology and ensures that the approximation errors of the end points of the intersection curve segments are less than a given tolerance. The error control is based on an effective solution to a set of polynomial inequality system using the root isolation technique. Some examples are presented to validate the robustness and effectiveness of the proposed algorithm.

关键词： Polynomial inequality system root isolation surface/surface intersection tolerance control trimmed quadrics

Pullout of the Cylindrical Helicoidal Fiber

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Acta Mechanica Solida Sinica 2024年第3期37卷 444-456页

作者： Chenhan Hu Weihao Tao Hongjun Yu Qinghua Qin Jianshan Wang department of Mechanics Tianjin UniversityTianjin300054China department of Astronautic Science and Mechanics Harbin Institute of TechnologyHarbin150001China department of Materials Science Shenzhen MSU-BIT UniversityShenzhen518172China

The multi-layer cylindrical helicoidal fiber structure(MCHFS)exists widely in biological materials such as bone and wood at the *** typically function as reinforcing elements to enhance the toughness of *** this study,we establish a shear lag-based pullout model of the cylindrical helicoidal fiber(CHF)for investigating interlayer stress transfer and debonding behaviors,with implications regarding the underlying toughening mechanism of *** on the shear lag assumptions,analytical solutions for the stress and displacement fields of the MCHFS during the pullout are derived by considering the CHF as a cylindrically monoclinic material and verified through the 3D finite element *** is found that the helical winding of CHF results in both axial and hoop interlayer shear *** the helical winding angle and the elastic moduli of the fiber and matrix have significant influences on interlayer stress *** work reveals a new interlayer stress transfer mechanism in the MCHFS existing widely in biological materials.

关键词： Cylindrical helicoidal fiber structure Cylindrically monoclinic material Helical winding of fiber Pullout Interlayer stress transfer

Centered Waves for the Two-dimensional Pseudo-Steady van der Waals Gas Satisfied Maxwell's Law Around a Sharp Corner

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Chinese Annals of Mathematics,Series B 2024年第04期45卷 537-554页

作者： Shuangrong LI Wancheng SHENG department of Mathematics Shanghai University Shanghai 200444 China department of Mathematics Zhejiang University of Science and Technology department of Mathematics Newtouch Center for Mathematics of Shanghai University Shanghai University

In this paper, the authors study the centered waves for the two-dimensional(2D for short) pseudo-steady supersonic flow with van der Waals gas satisfied Maxwell's law around a sharp corner. In view of the initial value of the specific volume and the properties of van der Waals gas, the centered waves at the sharp corner are constructed by classification. It is shown that the supersonic incoming flow turns the sharp corner by a centered simple wave or a centered simple wave with right-contact discontinuity or a composite wave(jump-fan, fan-jump or fan-jump-fan), or a combination of waves and constant state. Moreover, the critical angle of the sharp corner corresponding to the appearance of the vacuum phenomenon is obtained.

关键词： Centered simple wave Composite wave Two-dimensional Euler equations Van der Waals gas

In situ digital testing method for quality assessment of soft soil improvement with polyurethane

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.F.Wang C.J.Wang W.V.Yue Z.J.Zhang Z.Q.Yue department of Civil Engineering China University of Geosciences (Beijing)BeijingChina department of Water Science and Engineering Zhengzhou UniversityZhengzhouChina department of Geotechnical Engineering Tongji UniversityShanghaiChina department of Civil Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improvement by penetration injection with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are verified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty *** tests,*** compressive strength(UCS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty *** UCS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ *** method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process Constant drilling speed Soil improvement Quality assessment

High-yield and rapid isolation of extracellular vesicles by flocculation via orbital acoustic trapping:FLOAT

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Microsystems & Nanoengineering 2024年第1期10卷 313-323页

作者： Joseph Rufo Peiran Zhang Zeyu Wang Yuyang Gu Kaichun Yang Joseph Rich Chuyi Chen Ruoyu Zhong Ke Jin Ye He Jianping Xia Ke Li Jiarong Wu Yingshi Ouyang Yoel Sadovsky Luke P.Lee Tony Jun Huang department of Mechanical Engineering and Materials Science Duke UniversityDurhamNCUSA department of Biomedical Engineering Duke UniversityDurhamNCUSA department of Obstetrics Gynecologyand Reproductive SciencesMagee-Womens Research InstituteUniversity of PittsburghPittsburghPAUSA department of Microbiology and Molecular Genetics School of MedicineUniversity of PittsburghPittsburghPAUSA Renal Division and Division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolBostonMAUSA department of Bioengineering Department of Electrical Engineering and Computer ScienceUniversity of CaliforniaBerkeleyBerkeleyCAUSA department of Biophysics Institute of Quantum BiophysicsSungkyunkwan UniversitySuwonKorea

Extracellular vesicles(EVs)have been identified as promising biomarkers for the noninvasive diagnosis of various ***,challenges in separating EVs from soluble proteins have resulted in variable EV recovery rates and low ***,we report a high-yield(>90%)and rapid(<10 min)EV isolation method called FLocculation via Orbital Acoustic Trapping(FLOAT).The FLOAT approach utilizes an acoustofluidic droplet centrifuge to rotate and controllably heat liquid *** adding a thermoresponsive polymer flocculant,nanoparticles as small as 20 nm can be rapidly and selectively concentrated at the center of the *** demonstrate the ability of FLOAT to separate urinary EVs from the highly abundant Tamm-Horsfall protein,addressing a significant obstacle in the development of EV-based liquid *** to its high-yield nature,FLOAT reduces biofluid starting volume requirements by a factor of 100(from 20 mL to 200µL),demonstrating its promising potential in point-of-care diagnostics.

关键词： trapping utilize separating

Wildfire severity alters soil microbial exoenzyme production and fungal abundances in the southern Appalachian Mountains

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Pedosphere 2024年第5期34卷 865-878页

作者： Megan L.SCHILL Richard BAIRD Shawn P.BROWN Allison M.VEACH department of Integrative Biology University of Texas at San Antonio Biochemistry Molecular Biology Entomology and Plant Pathology Department Mississippi State University department of Biological Sciences The University of Memphis

Climate change has increased drought frequency and duration that are exacerbated by increased temperatures globally. This effect has, and will continue,to increase fire occurrence across many regions of North America. In the southern Appalachian Mountains, wildfires with high burn severity occurred in 2016due to increased drought and human activity. To investigate the effects of burn severity on soil physicochemical properties, microbial extracellular enzyme production, and microbial abundances in a temperate region, surface soils (0–15 cm) were collected from two sites (the Great Smoky Mountains National Park in Tennessee and the Nantahala National Forest in North Carolina, USA) spanning lightly, moderately, and severely burned areas, accompanied by adjacent unburned locations that act as controls. The soil samples were collected at three time points between 2017 and 2019 (i.e., 0.5, 1, and 2.5 years post-fire)among burn severity plots. Total hydrolytic enzyme production varied over time, with severe burn plots having significantly lower enzyme production at 2.5years post-fire. Individual enzymes varied among burn severities and across time post-fire. Light burn plots showed greater carbon-specific (β-glucosidase and β-xylosidase) and phosphorus-specific (acid phosphatase) enzyme activities at 0.5 years post-fire, but this effect was transient. At 2.5 years post-fire, theβ-xylosidase and acid phosphatase activities were lower in severe or moderate burn plots relative to the controls. In contrast, the activity of nitrogen-specific enzyme leucyl aminopeptidase was the lowest in severe burn plots at 0.5 years post-fire, but was the lowest in light burn plots at 2.5 years post-fire. The fungi:bacteria ratio declined with burn severity, indicating that fungi are sensitive or less resilient to high burn severity during recovery. These results suggest that wildfires alter trajectories for soil microbial structure and function within a 2.5-year timeframe, which potentially

关键词： 16S rRNA burn severity extracellular enzyme fungi:bacteria ratio internal transcribed spacer microbial structure

Rbm8a regulates neurogenesis and reduces Alzheimer's disease-associated pathology in the dentate gyrus of 5×FAD mice

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Neural Regeneration Research 2024年第4期19卷 863-871页

作者： Chenlu Zhu Xiao Ren Chen Liu Yawei Liu Yonggang Wang department of Neurology Lanzhou University Second Hospital department of Neurology The First Affiliated Hospital of Nanchang University department of Neurology Xiaogan City Central Hospital Health Service department of the Guard Bureau of the General Office of the Central Committee of the Communist Party of China Headache Center Department of NeurologyBeijing Tiantan HospitalCapital Medical University

Alzheimer’s disease is a prevalent and debilitating neurodegenerative condition that profoundly affects a patient’s daily functioning with progressive cognitive decline,which can be partly attributed to impaired hippocampal *** in the hippocampal dentate gyrus is likely to persist throughout life but declines with aging,especially in Alzheimer’s *** evidence indicated that RNA-binding protein 8A(Rbm8a)promotes the proliferation of neural progenitor cells,with lower expression levels observed in Alzheimer’s disease patients compared with healthy *** study investigated the hypothesis that Rbm8a overexpression may enhance neurogenesis by promoting the proliferation of neural progenitor cells to improve memory impairment in Alzheimer’s ***,Rbm8a overexpression was induced in the dentate gyrus of 5×FAD mice to validate this *** Rbm8a levels in the dentate gyrus triggered neurogenesis and abated pathological phenotypes(such as plaque formation,gliosis reaction,and dystrophic neurites),leading to ameliorated memory performance in 5×FAD *** sequencing data further substantiated these findings,showing the enrichment of differentially expressed genes involved in biological processes including neurogenesis,cell proliferation,and amyloid protein *** conclusion,overexpressing Rbm8a in the dentate gyrus of 5×FAD mouse brains improved cognitive function by ameliorating amyloid-beta-associated pathological phenotypes and enhancing neurogenesis.

关键词： Adora2a Alzheimer’s disease astrocyte cAMP signaling pathway dentate gyrus dystrophic neurites microglia neurogenesis plaque Rbm8a

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Categorizing methods for integrating machine learning with executable specifications

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Science China(Information Sciences) 2024年第1期67卷 5-19页

作者： David HAREL Raz YERUSHALMI Assaf MARRON Achiya ELYASAF department of Computer Science and Applied Mathematics Weizmann Institute of Science department of Software and Information Systems Engineering Ben-Gurion University of the Negev

Deep learning(DL),which includes deep reinforcement learning(DRL),holds great promise for carrying out real-world tasks that human minds seem to cope with quite *** promise is already delivering extremely impressive results in a variety of ***,while DL-enabled systems achieve excellent performance,they are far from *** has been demonstrated,in several domains,that DL systems can err when they encounter cases they had not hitherto ***,the opacity of the produced agents makes it difficult to explain their behavior and ensure that they adhere to various requirements posed by human *** the other end of the software development spectrum of methods,behavioral programming(BP) facilitates orderly system development using self-standing executable modules aligned with how humans intuitively describe desired system *** this paper,we elaborate on different approaches for combining DRL with BP and,more generally,machine learning(ML) with executable specifications(ES).We begin by defining a framework for studying the various approaches,which can also be used to study new emerging approaches not covered *** then briefly review state-of-the-art approaches to integrating ML with ES,continue with a focus on DRL,and then present the merits of integrating ML with *** conclude with guidelines on how this categorization can be used in decision making in system development,and outline future research challenges.

关键词： machine learning artificial intelligence grey box learning domain knowledge rules behavioral programming deep reinforcement learning survey

Effects of multiple shapes for steady flow with transformer oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 373-388页

作者： M.RAHMAN M.TURKYILMAZOGLU Z.MUSHTAQ department of Mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan department of Mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity *** system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c MATLAB *** outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower *** the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom *** ranges of various parameters taken into account are Pr=6.2,Re=2,M=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number

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