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Two-Stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： F.Momo TEMGOUA L.Akana NGUIMDO DNJOMO Environmental Energy Technologies Laboratory(EETL) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of Legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta Function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(F-TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the Legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method Legendre polynomial optical thickness moments of specific intensity conversion function transmittance reflectance

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Approximate solution of Volterra-Fredholm integral equations using generalized barycentric rational interpolant

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 220-238页

作者： Hadis Azin Fakhrodin Mohammadi Department of Mathematics University of HormozganBandar AbbasP.O.Box 3995Iran

It is well-known that interpolation by rational functions results in a more accurate approximation than the polynomials ***,classical rational interpolation has some deficiencies such as uncontrollable poles and low convergence *** contrast with the classical rational interpolants,the generalized barycentric rational interpolants which depend linearly on the interpolated values,yield infinite smooth approximation with no poles in real *** this paper,a numerical collocation approach,based on the generalized barycentric rational interpolation and Gaussian quadrature formula,was introduced to approximate the solution of Volterra-Fredholm integral *** types of points in the solution domain are used as interpolation *** obtained numerical results confirm that the barycentric rational interpolants are efficient tools for solving Volterra-Fredholm integral ***,integral equations with Runge’s function as an exact solution,no oscillation occurrs in the obtained approximate solutions so that the Runge’s phenomenon is avoided.

关键词： Barycentric rational interpolation Volterra-Fredholm integral equations Gaussian quadrature Runge's phenomenon

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A Second-Order Image Denoising Model for Contrast Preservation

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1406-1427页

作者： Wei Zhu Department of Mathematics University of AlabamaBox 870350TuscaloosaAL35487USA

In this work,we propose a second-order model for image denoising by employing a novel potential function recently developed in Zhu(J Sci Comput 88:46,2021)for the design of a regularization *** to this new second-order derivative based regularizer,the model is able to alleviate the staircase effect and preserve image *** augmented Lagrangian method(ALM)is utilized to minimize the associated functional and convergence analysis is established for the proposed *** experiments are presented to demonstrate the features of the proposed model.

关键词： Image denoising Variational model Image contrast Augmented Lagrangian method(ALM)

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Development of sustainable thermal insulation based on bio-polyester filled with date pits

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Journal of Bioresources and Bioproducts 2024年第1期9卷 74-89页

作者： Amal Mlhem Thomas Teklebrhan Evenezer Bokuretsion Basim Abu-Jdayil Chemical&Petroleum Engineering Department United Arab Emirates UniversityPO Box 15551United Arab Emirates National Water and Energy Center United Arab Emirates UniversityPO Box 15551United Arab Emirates

Date palm pit(DPP)-filled poly(-hydroxybutyrate)(PHB)composites were prepared,evaluated,and characterized to determine their thermal insulation *** conductivity values ranged between 0.086 and 0.100 W/(m·K).At a maximum filler concentration(50%(w)),the specific heat capacity and thermal diffusivity were 1183 J/(kg·K)and 0.0689 mm^(2)/s,*** DPP increased the thermal stability,and the highest compressive strength obtained was 80 MPa at 30%filler *** PHB-DPP composites exhibited promising water absorption(less than 6%)and tensile strength(6-14 MPa).Date-pit-based PHB composites could be used in sustainable building engineering and cleaner production.

关键词： Green construction material Sustainable thermal insulator Date pit Polyhydroxybutyrate

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Bulk-boundary and RPS thermodynamics from topology perspective

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Chinese Physics C 2024年第9期48卷 244-253页

作者： Jafar Sadeghi Mohammad Reza Alipour Saeed Noori Gashti Mohammad Ali S.Afshar Department of Physics Faculty of Basic SciencesUniversity of Mazandaran P.O.Box 47416-95447BabolsarIran School of Physics Damghan UniversityP.O.Box ***DamghanIran

In this study,we investigate the bulk-boundary and restricted phase space(RPS)thermodynamics of Rissner-Nordstrom(R-N)AdS and 6-dimensional charged Gauss-Bonnet AdS black ***,we examine the topological characteristics of the considered black holes and compare them with the results of extended *** determine that the topological behavior of the bulk-boundary thermodynamics is the same as that of the extended thermodynamics,whereas the RPS thermodynamics exhibits a distinct ***,we demonstrate that within the RPS formalism,there is only one critical point with a topological charge of+1(Q_(t)=+1).Moreover,in the RPS formalism,the inclusion of higher-derivative curvature terms in the form of GaussBonnet gravity does not alter the topological classification of critical points in charged AdS black holes.

关键词： bulk-boundary restricted phase space topological charge thermodynamics

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Post processing of additive manufactured Mg alloys:Current status,challenges,and opportunities

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Journal of Magnesium and Alloys 2024年第4期12卷 1283-1310页

作者： Nooruddin Ansari Fatima Ghassan Alabtah Mohammad I.Albakri Marwan Khraisheh Mechanical Engineering Program Texas A&M University at QatarP.O.Box 23874DohaQatar

Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight *** are also drawing notable attention in the medical industries owing to their biodegradability and a lower elastic modulus comparable to *** ability to manufacture near-net shape products featuring intricate geometries has sparked huge interest in additive manufacturing(AM)of Mg alloys,reflecting a transformation in the manufacturing ***,AM of Mg alloys presents more formidable challenges due to inherent properties,particularly susceptibility to oxidation,gas trapping,high thermal expansion coefficient,and low solidification *** leads to defects such as porosity,lack of fusion,cracking,delamination,residual stresses,and inhomogeneity,ultimately influencing the mechanical,corrosion,and surface properties of AM Mg *** address these issues,post-processing of AM Mg alloys are often needed to make them suitable for *** present article reviews all post-processing techniques adapted for AM Mg alloys to date,including heat treatment,hot isostatic pressing,friction stir processing,and surface *** utilization of these methods within the hybrid AM process,employing interlayer post-processing,is also *** post-processing conditions are reported,and their influence on the microstructure,mechanical,and corrosion properties are ***,future prospects and research directions are proposed.

关键词： Magnesium alloy Additive manufacturing Post-processing Heat treatment HIP

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Quantum speedup and non-Markovianity of an atom in structured reservoirs:pseudomodes as a good description of environmental memory

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Communications in Theoretical Physics 2024年第8期76卷 60-66页

作者： Maryam Hadipour Soroush Haseli Saeed Haddadi Faculty of Physics Urmia University of TechnologyUrmiaIran School of Physics Institute for Research in Fundamental Sciences(IPM)PO Box 19395-5531TehranIran Faculty of Physics Semnan UniversityPO Box 35195-363SemnanIran

Following the recent paper(Teittinen et al 2019 New J. Phys. 21 123041), one can see that in general there is no simple relation between non-Markovianity and quantum speed limit. Here, we investigate the connection between quantum speed limit time and non-Markovianity of an atom in structured environments(reservoirs) whose dynamics is governed by an exact pseudomode master equation(Garraway 1997 Phys. Rev. A 55 2290). In particular, we find an inverse relation between them, which means that the non-Markovian feature of the quantum process leads to speedup of evolution. Thus, there is a link between quantum speedup and memory effects for specific cases of dynamical evolution. Our results might shed light on the relationship between the speedup of quantum evolution and the backflow of information from the environment to the system.

关键词： quantum speed limit non-Markovianity pseudomode method structured environments

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Restimate:Recovery Estimation Tool for Resilience Planning

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Journal of Safety Science and Resilience 2024年第1期5卷 47-63页

作者： Scott Miles Megan Ly Nick Terry Youngjun Choe Department of Human Centered Design&Engineering Campus Box 352315University of WashingtonSeattleWA 98195United States of America Department of Industrial&Systems Engineering Box 352650University of WashingtonSeattleWA 98195United States of America

The *** Institute of Standards and Technology(NIST)published the Community Resilience Planning Guide in *** NIST Guide advocates for a participatory process for developing a performance measurement framework for the jurisdiction’s resilience against a scenario *** framework centers around tables of expected and desired recovery times for selected community assets,such as electricity,water,and natural gas *** NIST Guide does not provide a method for estimating the expected recovery ***,building high-fidelity computer models for such estimations requires substantial resources that even larger ju-risdictions cannot *** most promising approach to recovery time estimation is to systematically use data elicited from people to tap into the wisdom of the(knowledgeable)*** paper describes a novel research-through-design project to enable the computer-supported elicitation of recovery time series *** work is the first in the literature to examine people’s ability to estimate recovery curves and how design in-fluences such *** main contribution to resilience planning is three-fold:development of a new elicitation tool called Restimate,understanding its potential user base,and providing insights into how it can facilitate resilience *** is the first tool to enable evidence-based expert elicitation in any community with limited resources for resilience *** resilience planning,those who facilitate high-stakes planning activities under large uncertainties(e.g.,mission-critical system design and planning)will benefit from a similar research-through-design process.

关键词： expert elicitation disaster natural hazard infrastructure community resilience restoration user-centered design computer-supported cooperative work

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Consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTECH 2024年第2期5卷 239-246页

作者： J.M.Lukasiewicz C.C.M.van de Wiel L.A.P.Lotz M.J.M.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically Modified Organisms Directive(2001/18/EC)in the European *** the proposal of the European Commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques Consumer transparency Plant products

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Particle size distribution in a multi-zone circulating fluidized bed polymerization reactor

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Particuology 2024年第10期93卷 291-299页

作者： Mohammadhossein Hadadiyan Navid Mostoufi Reza Marandi Process Design and Simulation Research Centre School of Chemical EngineeringCollege of EngineeringUniversity of TehranP.O.Box 11155-4563TehranIran Polymer Research Group Petrochemical Research and Technology CompanyNational Petrochemical CompanyP.O.Box 14358/84711TehranIran

This research focuses on modeling a multi-zone circulating reactor(MZCR)in the polypropylene production *** these reactors,designed for polyolefin production,small catalyst particles(20–300μm)initiate polymerization in the presence of monomer *** reactor consists of two main regions:the riser and the *** riser operates in the fast fluidization and the downer is in the moving bed *** the two-fluid model with the Eulerian-Eulerian approach,the dynamics of both solid and gas phases were modeled by applying Newton's laws of motion and assuming spherical *** population balance of particles within the reactor was also coupled with the equations of *** simultaneous solution of these equations provides valuable insights into particle and fluid behavior,revealing trends such as the growth of polymer ***,the impact of various operating conditions was *** study also examined the effects of design parameters(gas inlet velocity,average inlet diameter,and temperature)on the system *** instance,it was shown that in the case where the solid circulation flux is 30 kg/(m^(2) s)the velocity of particles in the bed increases from 0.4 at the inlet to 1.1 m/s in the fully developed zone,when it is 43 kg/(m^(2) s)the velocity of particles increases from 0.3 to 1.4 m/s,and when it is 55 kg/(m^(2) s),it is increased from 0.22 to 1.5 m/***,trends in particle size distribution based on temperature adjustments were *** study showed that higher temperatures accelerate the polymerization reaction rate,promoting faster growth kinetics and the formation of larger particles.

关键词： Fluidization Polymerization Gas-solid flow Multi-zone circulating reactor(MZCR) CFD-PBM Two-fluidmodel

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