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Plasma Science and Technology 2017年第9期19卷 35-40页

作者： G c DAS Gyan Darshan Academy VIP RoadGuwahati-781022India

Based on quasipotential analysis, a plasma sheath is studied through the derivation of the Sagdeev potential equation in dusty plasma coexisting with adiabatically heated electrons and ions. Salient features as to the existence of sheaths are shown by solving the Sagdeev potential equation through the Runge–Kutta method, with appropriate consideration of adiabatically heated electrons and ions in the dynamical system. It has been shown that adiabatic heating of plasma sets a limit to the critical dust speed depending on the densities and Mach number, and it is believed that its role is very important to the sheath. One present problem is the contraction of the sheath region whereby dust grains levitated into the sheath lead to a crystallization similar to the formation of nebulons and are compressed to a larger chunk of the dust cloud by shrinking of the sheath. Our overall observations advance knowledge of sheath formation and are expected to be of interest in astroplasmas.

关键词： sheath heated dynamical Kutta Runge derivation shrinking coexisting grains compressed

Theoretical Model of Steel continuous casting Technology

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Journal of Iron and Steel Research International 2009年第1期16卷 12-16页

作者： c Gheorghies I crudu c Teletin c Spanu Faculty of Science Dunarea de JosUniversity of GalatiRO800008Romania Faculty of Mechanical Engineering Dunarea de JosUniversity of GalatiRO800008Romania

A theoretical model adapted for studying steel continuous casting technology was proposed. The model based on system theory contained input/output, command, and control parameters. The process was divided .into five stages, i. e. , tundish, mold, guiding system, guiding-drawing system, and guiding-drawing-soft reduction system. The model can be used to describe the physicochemical processes, thermal processes, chemical processes, and characteristics of the cast material according to the above-mentioned stages. It can also be applied to other metallurgical technologies and even to other industries （chemistry, food, etc. ）.

关键词： steel casting technology system theory modeling

Evidence-based guidelines for greener,healthier,more resilient neighbourhoods:Introducing the 3–30–300 rule

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Journal of Forestry Research 2023年第3期34卷 821-830页

作者： cecil c.Konijnendijk Nature Based Solutions Institute BarcelonaSpain

The important contributions of urban trees and green spaces to for example,climate moderation and public health have been *** paper discusses guidelines and norms that promote the benefi ts of viewing green,living amongst green,and having easy access to green spaces for recreational *** trees and other vegetation in sight from one’s home,place of work,or school has important mental health and performance benefi *** tree canopy cover is positively associated with cooling and other aspects of climate *** public green spaces in proximity to one’s home stimulates regular use of these areas and results in positive impacts on mental,physical,and social *** analyzing existing guidelines and rules for urban green space planning and provision,a new,comprehensive guideline is presented,known as the‘3–30–300 rule’for urban *** guideline aims to provide equitable access to trees and green spaces and their benefi ts by setting the thresholds of having at least 3 well-established trees in view from every home,school,and place of work,no less than a 30%tree canopy in every neighbourhood;and no more than 300 m to the nearest public green space from every *** implementation of this new guideline is discussed,as well as the advantages and disadvantages of using this evidence-based but also clear and simple rules.

关键词： climate adaptation Guidelines Public health Trees Urban forestry

Interfacial Instability of Two Bonded Elastic Bodies Driven by Interface or Bulk Residual Stress

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Acta Mechanica Solida Sinica 2023年第6期36卷 914-920页

作者： c.Q.Ru Department of Mechanical Engineering University of AlbertaEdmonton T6G 2G8Canada

Inspired by recent research interest in the interface wrinkling of bonded materials in diverse areas of 3D printing,the present work studies the interfacial instability of two bonded elastic bodies driven by negative interfacial tension or compressible bulk residual *** interfacial instability modes decaying exponentially with distance from the interface,the present model is formulated for two bonded elastic half-spaces with a planar interface under plane *** explicit expression is given for the wavenumber of interfacial instability driven by negative interfacial tension,and a critical condition is derived for interfacial instability driven by compressive bulk residual *** derived results are validated with comparison to known results on surface instability of an elastic half-space,and the role of shear modulus ratio and Poisson’s ratios of two bonded elastic bodies in interfacial instability,an issue to be addressed in literature,is studied with specific reference to material parameters used in some areas of 3D printing.

关键词： Interfacial tension Surface tension Interfacial instability 3D printing Interface wrinkling

ESTIMATOR cOMPETITION FOR POISSON PROBLEMS

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Journal of computational Mathematics 2010年第3期28卷 309-330页

作者： c.carstensen c.Merdon Humboldt-Universitt zu Berlin Department of computational Science and Engineering Yonsei University

We compare 13 different a posteriori error estimators for the Poisson problem with lowest-order finite element discretization. Residual-based error estimators compete with a wide range of averaging estimators and estimators based on local problems. Among our five benchmark problems we also look on two examples with discontinuous isotropic diffusion and their impact on the performance of the estimators. （Supported by DFG Research center MATHEON.）

关键词： Finite element methods A posteriori error estimators.

Stochastic contrast Measures for SAR Data: A Survey

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雷达学报（中英文） 2019年第6期8卷 758-781页

作者： Alejandro c.Frery La ccAN–Laboratório de computa??o científica e Análise Numérica Universidade Federal de Alagoas

“contrast”is an generic denomination for“difference”.Measures of contrast are a powerful tool in image processing and analysis,e.g.,in denoising,edge detection,segmentation,classification,parameter estimation,change detection,and feature *** present a survey on techniques that aim at measuring the contrast between(i)samples of SAR imagery,and(ii)samples and models,with emphasis on those that employ the statistical properties of the data.

关键词： contrast Divergence Entropy Geodesic distance Statistics Synthetic Aperture Radar(SAR)

Axisymmetric wetting of a liquid droplet on a stretched elastic membrane

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Applied Mathematics and Mechanics(English Edition) 2023年第6期44卷 997-1006页

作者： c.Q.RU Department of Mechanical Engineering University of AlbertaEdmontonAB T6G 2G8Canada

Wetting of a liquid droplet on another liquid substrate is governed by the well-known Neumann *** present work aims to develop an explicit modified version of the Neumann equations for axisymmetric wetting of a liquid droplet on a highly stretched elastic membrane of non-zero bending *** explicit modified form of the Neumann equations is derived to determine the two contact angles,which is reduced to Young's equation for a liquid droplet on a rigid membrane or to the Neumann equations for a liquid droplet on another liquid *** implications of the modified Neumann equations are examined by comparison with some previous results reported in the recent literature,particularly considering the ranges of material and geometrical parameters of the liquid droplet-membrane system which have not been recently addressed in the literature.

关键词： Neumann equation Young's equation liquid droplet membrane pretension

Effect of bio-tissue deformation behavior due to intratumoral injection on magnetic hyperthermia

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chinese Physics B 2023年第3期32卷 330-339页

作者：汤云东邹建 Rodolfo c.c.Flesch 金涛 college of Physics and Information Engineering Fuzhou UniversityFuzhou 350116China Departamento de Automação e Sistemas Universidade Federal de Santa Catarina88040-900 FlorianópolisSCBrazil college of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

Thermal damage of malignant tissue is generally determined not only by the characteristics of bio-tissues and nanoparticles but also the nanofluid concentration distributions due to different injection methods during magnetic *** latter has more advantages in improving the therapeutic effect with respect to the former since it is a determining factor for the uniformity of nanofluid concentration distribution inside the tumor *** study investigates the effect of bio-tissue deformation due to intratumoral injection on the thermal damage behavior and treatment temperature distribution during magnetic hyperthermia,in which both the bio-tissue deformation due to nanofluid injection and the mass diffusion after injection behavior are taken into *** nanofluid flow behavior is illustrated by two different theoretical models in this study,which are Navier–Stokes equation inside syringe needle and modified Darcy’s law inside *** diffusion behavior after nanofluid injection is expressed by a modified convection–diffusion equation.A proposed three-dimensional liver model based on the angiographic data is set to be the research object in this study,in which all bio-tissues are assumed to be deformable porous *** results demonstrate that the injection point for syringe needle can generally achieve the maximum value in the tissue pressure,deformation degree,and interstitial flow velocity during the injection process,all of which then drop sharply with the distance away from the injection *** addition to the bio-tissue deformation due to injection behavior,the treatment temperature is also highly relevant to determine both the diffusion duration and blood perfusion rate due to the thermal damage during the therapy.

关键词： tissue deformation thermal apoptosis analysis heat transfer mass transfer

Modeling the effects of salt concentration on aqueous and organic electrolytes

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npj computational Materials 2023年第1期9卷 546-552页

作者： Stephanie c.c.van der Lubbe Pieremanuele canepa Department of Materials Science and Engineering National University of Singapore9 Engineering Drive 1117575 SingaporeSingapore Department of chemical and Biomolecular Engineering National University of Singapore4 Engineering Drive 4117585 SingaporeSingapore Department of Electrical and computer Engineering and Texas center for Superconductivity University of HoustonHoustonTX 77204USA

Understanding the thermodynamic properties of electrolyte solutions is of vital importance for a myriad of physiological and technological *** mean activity coefficientγ±is associated with the deviation of an electrolyte solution from its ideal behavior and may be obtained by combining the Debye-Hückel(DH)and Born(B)***,the DH and B equations depend on the concentration and temperature-dependent static permittivity of the solutionεr(c,T)and the size of the solvated ions ri,whose experimental data is often not ***,we use a combination of molecular dynamics and density functional theory to predictεr(c,T)and ri,which enables us to apply the DH and B equations to any technologically relevant aqueous and nonaqueous electrolyte at any concentration and temperature of interest.

关键词： equations electrolyte apply

Spatial assessment of the areas sensitive to degradation in the rural area of the municipality (c)ukarica

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International Soil and Water conservation Research 2019年第1期7卷 71-80页

作者： Natalija Momirovi(c) Ratko Kadovi(c) Veljko Perovi(c) Milo(s)Marjanovi(c) Aleksandar Baumgertel Institute of Forestry Kneza Vi(s)eslava 311030 BelgradeSerbia Faculty of Forestry University of BelgradeKneza Vi(s)eslava 111030 BelgradeSerbia Institute for Biological Research'Sini(s)a Stankovi(c)' University of BelgradeBulevar despota Stefana 14211060 BelgradeSerbia Faculty of Mining and Geology University of BelgradeDu(s)ina 711000 BelgradeSerbia

In this paper,the assessment of the sensitivity of the soil in the rural area of (c)ukarica municipality to the processes of degradation is *** areas,especially in the vicinity of large cities,are exposed to numerous processes of degradation:soil erosion,urban and industrial zone expansion at the expense of fertile agricultural soils,activation of landslides and a number of other significant ecological *** on the characteristics of the research area,the MEDALUS (Mediterranean Desertification and Land Use) model was applied,and for the assessment of sensitivity to the processes of degradation the main quality indicators were considered:soil,climate,vegetation and *** each of the analyzed quality indicators,parameter groups were *** parameter is quantified according to the defined method by giving them a sensitivity coefficient between 1.0 and *** 10.0 has been applied to analyze and prepare layers of quality ***,the geometric mean for all four quality indicators was used to generate the map of environmental sensitivity to *** results obtained show that 41.54% of the study area is classified as critical;22.34% of the surface as fragile;8.47% of the areas are potentially endangered and 9.58% not threatened to degradation *** results have also shown that MEDALUS model is a functional tool for simulations which support sustainable land management in the areas prone to degradation.

关键词： MEDALUS Land degradation Landslides Human pressures GIS mapping