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Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： m.B.KIRKHAm Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the moon or mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the moon and mars.

关键词： soils soil bases

Enhanced Wolf Pack Algorithm (EWPA) and Dense-kUNet Segmentation for Arterial Calcifications in mammograms

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Computers, materials & Continua 2024年第2期78卷 2207-2223页

作者： Afnan m.a.hassan College of Computing and Information Technology Shaqra UniversityShaqra11961Saudi Arabia

Breast Arterial Calcification(BAC)is a mammographic decision dissimilar to cancer and commonly observed in elderly *** identifying BAC could provide an expense,and be *** Deep Learning(DL)methods have been introduced for automatic BAC detection and quantification with increased ***,classification with deep learning had reached higher efficiency,but designing the structure of DL proved to be an extremely challenging task due to overfitting *** also is not able to capture the patterns and irregularities presented in the *** solve the overfitting problem.a. optimal feature set has been formed by Enhanced Wolf Pack Algorithm(EWPA),and their irregularities are identified by Dense-kUNet *** this paper,Dense-kUNet for segmentation and optimal feature has been introduced for classification(severe,mild,light)that integrates DenseUNet and *** bound links exist among adjacent modules,allowing relatively rough data to be sent to the following component and assisting the system in finding higher *** major contribution of the work is to design the best features selected by Enhanced Wolf Pack Algorithm(EWPA),and modified Support Vector machine(mSVm)based learning for classification.k-Dense-UNet is introduced which combines the procedure of Dense-UNet and kU-Net for image *** bound associations occur among nearby sections,allowing relatively granular data to be sent to the next subsystem.a.d benefiting the system in recognizing smaller *** proposed techniques and the performance are tested using several types of analysis techniques 826 filled digitized *** proposed method achieved the highest precision,recall,F-m.a.ure,and accuracy of 84.4333%,84.5333%,84.4833%,and 86.8667%when com.a.ed to other methods on the Digital Database for Screening mammography(DDSm).

关键词： Breast arterial calcification cardiovascular disease semantic segmentation transfer learning enhanced wolf pack algorithm.a.d modified support vector machine

^(4)He monolayer on graphene:a quantum monte Carlo study

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Communications in Theoretical Physics 2024年第9期76卷 149-157页

作者： S Yu m Boninsegni Department of Physics University of AlbertaEdmontonAlbertaT6G 2H5Canada

We revisit the problem of adsorption of a single^(4)He layer on graphene,focusing on the commensurate(C_(1/3))crystalline phase,specifically on whether it may possess a nonzero superfluid response,and on the existence of superfluid phases,either(metastable)liquid or vacancy-doped *** make use of canonical quantum monte Carlo simulations at zero and finite temperature,based on a realistic microscopic model of the *** results confirm the absence of any superfluid response in the commensurate crystal,and that no thermodynamically stable uniform phase exists at lower *** evidence of a possibly long-lived,metastable superfluid phase at C_(1/3)coverage is ***,the results of ground-state projection methods and finite-temperature simulations are entirely consistent.

关键词： superfluidity low-dimensional systems quantum monte Carlo helium supersolids

Effects of Andrade and Burgers rheologies on glacial isostatic adjustment modeling in Antarctica

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Geodesy and Geodynamics 2024年第5期15卷 429-440页

作者： Alexandre Boughanemi Anthony mémin UniversitéCôte d'Azur CNRSObservatoire de la Côte d'AzurIRDGéoazur250 rue Albert EinsteinSophia Antipolis 06560 ValbonneFrance

Variations in ice mass deform the Earth and modify its gravity field,a process known as Glacial Isostatic Adjustment(GIA).GIA in Antarctica remains poorly constrained due to the cumulative effect of past and present ice-mass changes,the unknown history of the past ice-mass change,and the uncertainties on the mechanical properties of the *** paper investigates the effect of using Andrade and Burgers viscoelastic rheologies,rather than the commonly used maxwell rheology,to model GIA-induced deformation in *** Love number and Green's function formalism.a.e used to compute the radial surface displacements and the gravity changes induced by the past and present ice-mass *** consider an Earth model whose elastic properties and radial structure are averaged from the Preliminary Reference Earth model and two viscosity profiles to account for the recently published results on the present ice-mass *** the three rheological laws affects the temporal response of the Earth differently,leading to smaller discrepancies than those induced by the two viscosity *** differences are the largest between maxwell and Burgers rheologies during the 100-1000 years following the beginning of the surface-mass *** show that using the Andrade and Burgers rheologies allows the Earth to respond on decennial to centennial time scales,up to 10 m more than *** only the recent ice-mass changes,the deformation rates derived from Burgers and Andrade rheologies are several times larger than those estimated by maxwell rheology.

关键词： GIA Antarctica modeling Rheology Displacement Viscosity GNSS

Increasing the maximum Capacity Path in a Network and Its Application for Improving the Connection Between Two Routers

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Tsinghua Science and Technology 2024年第3期29卷 753-765页

作者： Adrian m.Deaconu Javad Tayyebi Department of mathematics and Computer Science Transilvania University of BrasovBrasov 500036Romania Department of Industrial Engineering Birjand University of TechnologyBirjand 000097Iran

Abstract:This paper addresses the problem of improving the optimal value of the maximum Capacity Path(mCP)through expansion in a flexible network,and minimizing the involved *** only condition applied to the cost functions is to be non-decreasing *** is a non-restrictive condition,reflecting the reality in practice,and is considered for the first time in the ***,the total cost of expansion is a combination of max-type cost(e.g.,for supervision)and sum-type cost(*** building infrastructures,price of materials,price of labor,etc.).For this purpose,two types of strategies are combined:(l)increasing the capacity of the existing arcs,and(l)adding potential new *** different problems are introduced and *** the problems have immediate applications in Internet routing *** first one is to extend the network,so that the capacity of an mcP in the modified network becomes equal to a prescribed value,therefore the cost of modifications is minimized.A strongly polynom.a.-time algorithm is deduced to solve this *** second problem is a network expansion under a budget constraint,so that the capacity of an mcP is maximized.A weakly polynom.a.-time algorithm is presented to deal with *** the special case when all the costs are linear,a meggido's parametric search technique is used to develop an algorithm for solving the problem in strongly polynom.a. *** new approach has a time complexity of O(n^(4)),which is better than the time complexity of O(n4 log(n)of the previously known method from literature.

关键词： maximum Capacity Path(mCP) network expansion Internet routing polynom.a.-time algorithms

Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power Laser Science and Engineering 2024年第3期12卷 62-68页

作者： L.R.Yin X.F.Li Y.J.Gu N.Cao Q.Kong m.Büscher S.m.Weng m.Chen Z.m.Sheng Key Laboratory of Nuclear Physics and Ion-beam.a.plication(moE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina SANKEN(Institute of Scientific and Industrial Research) Osaka UniversityOsakaJapan Sichuan Research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für Laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key Laboratory for Laser Plasmas(moE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

magnesium oxide(mgO)nanoadsorbents in wastewater treatment:A comprehensive review

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Journal of magnesium.a.d Alloys 2024年第5期12卷 1709-1773页

作者： H.C.S.Perera V.Gurunanthanan Anoop Singh m.m.m.G.P.G.mantilaka G.Das Sandeep Arya Department of Physics Khalifa UniversityAbu Dhabi12788United Arab Emirates Postgraduate Institute of Science University of PeradeniyaPeradeniyaSri Lanka Department of Humanities and Sciences Guru Nanak Institutions Technical CampusIbrahimpatnamHyderabad501506India Centre for Global Health Research Saveetha Medical College and HospitalsSaveetha Institute of Medical and Technical SciencesChennai602105Tamil NaduIndia Department of Physics University of JammuJammu and Kashmir180006India

Wastewater contamination by heavy metals and synthetic dyes presents a significant environmental challenge,necessitating effective and sustainable separation *** review article provides a detailed examination of magnesium oxide(mgO)nanoparticles as an innovative nanoadsorbent for wastewater treatment,with a specific focus on heavy metal and dye *** review comprehensively explores various aspects of mgO nanoparticles,including their structural characteristics and synthesis *** article delves into the morphology and crystallographic arrangement of mgO nanoparticles,offering insights into their structural *** the complexity of adsorption processes,the review identifies and analyzes parameters influencing the adsorption efficiency of mgO nanoparticles,such as temperature,pH,contact time,initial concentration,and co-existing *** interplay between these parameters and the adsorption capability of mgO nanoparticles emphasizes the importance of optimizing operational ***,the review assesses various synthesis methods for mgO nanoparticles,including sol-gel,hydrothermal,precipitation,green synthesis,solvothermal,and template-assisted *** discusses the advantages,limitations,and resulting nanoparticle characteristics of each method,enabling readers to grasp the implications of synthesis processes on adsorption *** comprehensive review consolidates current insights into the effectiveness of mgO nanoparticles as a potent nanoadsorbent for removing heavy metals and dyes from wastewater covering a wide spectrum of aspects related to mgO ***,there is a need to investigate the use of mgO in the treatment of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatment applications in real-time.

关键词： mgO nanoparticles Nanoadsorbent Wastewater treatment Heavy metals Dye separation Adsorption Synthesis methods

The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming

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Applied mathematics and mechanics(English Edition) 2024年第4期45卷 711-724页

作者： F.JAZINI DORCHEH m.GHASSEmI Fuel Cells and Nano Systems(FCNS)Laboratory Department of Mechanical EngineeringK.N.Toosi University of TechnologyTehran 19697Iran

In recent decades,the importance of surface acoustic waves,as a biocom.a.ible tool to integrate with microfluidics,has been proven in various medical and biological *** numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the *** this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation *** the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load *** particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous *** is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation.

关键词： surface acoustic wave microfluidics numerical simulation particle tracing acoustic streaming

Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method

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Nuclear Science and Techniques 2024年第1期35卷 145-154页

作者： m.Hajipour G.R.Ansarifar Department of Nuclear Engineering Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

Nuclear power plants exhibit non-linear and time-variable ***,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWR)is a fourth-generation conceptual *** an SCWR,the non-linear dynamics of the reactor require a controller capable of control-ling the *** this study,a pressure-tube-type SCWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled *** an SCWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power *** point kinetics equations with three groups of delayed neutrons were used in the ***-order and classic sliding mode controllers were separately manufactured to control the plant and were com.a.ed with the PI controllers speci-fied in previous *** controlled parameters were reactor power,steam temperature,and ***,for these parameters,the PI controller had certain instabilities in the presence of *** classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering *** was highly accurate and stable and had a small computational *** reality,it followed the desired values without oscillations and chattering.

关键词： Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model