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Pedosphere 2011年第2期21卷 170-177页

作者： h.r.MOTAGhIAN j.MOhAMMADI Department of Soil Science Agriculture CollegeShahrekord UniversityShahrekord (Iran)

Several methods,including stepwise regression,ordinary kriging,cokriging,kriging with external drift,kriging with varying local means,regression-kriging,ordinary artificial neural networks,and kriging combined with artificial neural networks,were compared to predict spatial variation of saturated hydraulic conductivity from environmental *** methods except ordinary kriging allow for inclusion of secondary *** secondary spatial information used was terrain attributes including elevation,slope gradient,slope aspect,profile curvature and contour curvature.A multiple jackknifing procedure was used as a validation *** mean square error (rMSE) and mean absolute error (MAE) were used as the validation indices,with the mean rMSE and mean MAE used to judge the prediction *** performance by ordinary kriging was poor,indicating that prediction of saturated hydraulic conductivity can be improved by incorporating ancillary data such as terrain *** combined with artificial neural networks performed *** prediction models made better use of ancillary information in predicting saturated hydraulic conductivity compared with the competing *** combination of geostatistical predictors with neural computing techniques offers more capability for incorporating ancillary information in predictive soil *** is great potential for further research and development of hybrid methods for digital soil mapping.

关键词： digital elevation model geostatistics soil hydraulic properties spatial mapping

基于多参数MrI影像组学鉴别2 cm以下的小胰腺导管腺癌与神经内分泌肿瘤

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国际医学放射学杂志 2025年第1期 119-120页

作者： K.Shen W.j.Su C.M.Liang D.Shi j.h.Sun r.S.Yu 李晗

摘要目的评估基于Mr的影像组学分析在术前鉴别小尺寸（<2 cm）胰腺导管腺癌（PDAC）与神经内分泌肿瘤（PNET）中的应用。方法回顾性收集2个中心共计197例病

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Experimental Study of Forced Convective heat Transfer in a Copper Tube Using Three Types of Nanofluids

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Fluid Dynamics & Materials Processing 2025年第2期21卷 351-370页

作者： Zahraa N.hussain jamal M.Ali hasan S.Majdi Abbas j.Sultan h.Al-Naseri Department of Chemical Engineering University of Technology-IraqBaghdad10066Iraq Department of Chemical Engineering and Petroleum Industries Al-Mustaqbal UniversityBabylon51001Iraq Chemical Engineering Department College of EngineeringTikrit UniversityTikrit34001Iraq

The use of nanofluids as heat transfer media represents an innovative strategy to enhance heat transfer *** study investigates experimentally the turbulent convective heat transfer characteristics of waterbased nanofluids containing TiO_(2),CuO,and graphene nanoplatelet(GNP)nanoparticles as they flow through a copper *** the dynamic viscosity and thermal conductivity of these nanofluids were modeled and experimentally measured across varying nanoparticle concentrations(0.01,0.02,and 0.03 vol.%)and temperatures(25℃,35℃,and 45℃).The findings indicate that the behavior of nanofluids depends on the parameter used for comparison with the base ***,both the friction factor and heat transfer coefficient increase with higher nanoparticle volume concentrations at a constant reynolds *** results further reveal that the GNP/water nanofluid,with a volume concentration of 0.03%at 45℃,exhibit the highest Nusselt number,followed by the CuO/water and TiO_(2)/water nanofluids,with respective increases of 17.8%,11.09%,and 8.11%.

关键词： Nanofluid heat transfer coefficient thermal conductivity heat transfer enhancement

Generalizing plant–water relations to landscapes

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journal of Plant Ecology 2011年第1期4卷 101-113页

作者： r.h.Waring j.j.Landsberg College of Forestry Oregon State UniversityCorvallisOR 97331USA Withycombe Church LaneMt WilsonNSW 2786Australia

Aims Changing climate and land use patterns make it increasingly important that the hydrology of catchments and ecosystems can be reliably *** aim of this paper is to identify the biophysical factors that determine the rates of water vapor loss from different types of vegetation,and to seek,from an array of currently available satelliteborne sensors,those that might be used to initialize and drive landscape-level hydrologic *** Findings Spatial variation in the mean heights,crowd widths,and leaf area indices(LAI)of plant communities are important structural variables that affect the hydrology of *** stomatal conductance(G)imposes physiological limitation on transpiration by *** maximum value of G(Gmax)is closely linked to canopy photosynthetic capacity,which can be estimated via remote sensing of foliar chlorophyll or nitrogen *** be modeled as a nonlinear multipliable function of:(i)leaf–air vapor pressure deficit,(ii)water potential gradient between soil and leaves,(iii)photosynthetically active radiation absorbed by the canopy,(iv)plant nutrition,(v)temperature and(vi)the CO_(2) concentration of the *** surveys with Light Detection and ranging(LiDAr)and interferometric rADAr,along with high-resolution spectral coverage in the visible,near-infrared,and thermal infrared bands,provide,along with meteorological data gathered from weather satellites,the kind of information required to model seasonal and interannual variation in transpiration and evaporation from landscapes with diverse and dynamic vegetation.

关键词： canopy stomatal conductance plant water relations process-based models remote sensing

Microstructures in a carburized steel after isothermal pearlitic treatment

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journal of Materials Science & Technology 2023年第29期160卷 66-75页

作者： j.Abraham Mathews h.Farahani j.Sietsma r.h.Petrov M.G.Mecozzi M.j.Santofimia Department of Materials Science and Engineering Delft University of TechnologyMekelweg 22628 CDDelftThe Netherlands Tata Steel research&Development IJmuidenThe Netherlands Department of Electromechanical Systems and Metal EngineeringGhent UniversityTech Lane Ghent Science park-Campus A ZwijnaardeTechnologiepark 46Belgium

The influence of carbon concentration variations on pearlite formation(20 h at 600℃)in a case-carburized steel is *** resultant microstructure shows three distinct regions:carburized case,a transition region,and the original *** microstructural transition from the case to the core regions is observed to be relatively *** investigated region of the carburized case(0.9 wt.%C)con-tains two types of pearlite:ferrite+cementite and ferrite+M_(23)C_(6),where the pearlitic aggregate with M_(23)C_(6)shows faster formation *** kinetics of pearlite formation in the transition region(0.3 wt.%C)is very slow and is observed with only M_(23)C_(6)*** around 40%austenite decomposes into pearlite in the transition region,which,in comparison to the carburized case region of 0.9 wt.%C is a fraction that is lower by a factor of *** is absent in the investigated core region(0.16 wt.%C).The microstructure in this region is predominantly martensite and pro-eutectoid ferrite,with a fraction of ferrite well below the equilibrium *** formation in this region is limited by the redistribution of mainly Ni,Mn,and Cr,and their resulting solute drag effect on the austenite/ferrite interface.A ther-modynamic and kinetic argumentation of these observations is provided with the help of thermodynamic data,precipitation simulations,and a general mixed-mode Gibbs energy balance model.

关键词： Pearlite formation Carburized steel M 2_(3)C_(6)carbide Kinetics Solute drag

3D Micromechanical Modeling of Failure and Damage Evolution in Dual Phase Steel Based on a real 2D Microstructure

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Acta Mechanica Solida Sinica 2016年第1期29卷 95-110页

作者： M.r.Ayatollahi A.Ch.Darabi h.r.Chamani j.Kadkhodapour Fatigue and Fracture Lab. Center of Excellence in Experimental Solid Mechanics and DynamicsSchool of Mechanical EngineeringIran University of Science and Technology

A plate of dual phase steel was produced from low carbon steel with intercritical annealing treatment. Its optically determined surface microstructure was utilized to construct three different microstructural models. To describe the ductile damage in the ferritic matrix, the Gurson-Tvergaard-Needleman model was used with the failure in the martensite phase being ignored. The numerical results obtained for the mechanism of void initiation and coalescence were compared with the experimental observations. The numerical results obtained from the randomly extruded 3D model showed a significantly better agreement with the experimental ones than those obtained from the 2D model or the uniformly extruded 3D model.

关键词： dual phase steel 3D model microstructure micromechanical modeling GTN dam-age model

Cyclic behavior of reinforced sand under principal stress rotation

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journal of rock Mechanics and Geotechnical Engineering 2017年第4期9卷 585-598页

作者： Alaa h.j. Al-rkaby A. Chegenizadeh h.r. Nikraz Department of Civil Engineering School of Civil and Mechanical Engineering Curtin University Perth Australia

Although the cyclic rotation of the principal stress direction is important,its effect on the deformation behavior and dynamic properties of the reinforced soil has not been reported to *** carried out on large-scale hollow cylinder samples reveal that the cyclic rotation of the principal stress direction results in significant variations of strain components(ε,ε,εand γ) with periodic characteristics despite the deviatoric stress being constant during *** oscillation can be related to the corresponding variations in the stress components and the anisotropic fabric that rotate continuously along the principal stress *** under rotation appears to develop a plastic *** trends are observed for reinforced sand,but the shear interaction,the interlocking between particles and reinforcement layer,and the confinement result in significant reductions in the induced strains and associated irrecoverable plastic *** of the strains occur in the first cycle,and as the number of cycles increases,the presence of strains becomes very small,which is almost *** indicates that the soil has reached anisotropic critical state(ACS),where a stable structure is formed after continuous orientation,realignment and rearrangement of the particles accompanied with increasing cyclic *** in the range of 60°-135° produces more induced strains even in the presence of the reinforcement,when compared with other *** relates to the extension mode of the test in this range in which σ>σand to the relative approach between the mobilized plane and the weakest horizontal *** results in an increase in shear modulus while it appears to have no effect on the damping *** cycles of rotation result in an increase in shear modulus and lower damping ratio due to the densification that causes a decrease in shear strain and less dissipation of energy.

关键词： Cyclic rotation Principal stress direction reinforced sand Strain components Damping ratio Shear modulus

CONVErGENCE OF ADAPTIVE EDGE ELEMENT METhODS FOr ThE 3D EDDY CUrrENTS EQUATIONS

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journal of Computational Mathematics 2009年第5期27卷 657-676页

作者： r.h.W.hoppe j.Schberl Institut fur Mathematik Universitat AugsburgD-86159AugsburgGermanyand Department of MathematicsUniversity of HoustonHoustonTX 77204-3008USA Dept.for Mathematics CCES(Center for Computational Engineering Science) RWTH AachenD-52074 AachenGermany

We consider an Adaptive Edge Finite Element Method （AEFEM） for the 3D eddy currents equations with variable coefficients using a residual-type a posteriori error estimator. Both the components of the estimator and certain oscillation terms, due to the occurrence of the variable coefficients, have to be controlled properly within the adaptive loop which is taken care of by appropriate bulk criteria. Convergence of the AEFEM in terms of reductions of the energy norm of the discretization error and of the oscillations is shown. Numerical results are given to illustrate the performance of the AEFEM.

关键词： Adaptive edge elements 3D eddy currents equations Convergence analysis,Error and oscillation reduction residual type a posteriori error estimates.

FLOW STrESS MODEL FOr hArD MAChINING OF AISI h13 WOrK TOOL STEEL

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 741-748页

作者： h. Yan j. hua r. Shivpuri School of Mechanical-Electrical Engineering Nanchang University Nanchang 330029China The Ohio State University Columbus OH 43210 USA

An approach is presented to characterize the stress response of workpiece in hard machining, accounted for the effect of the initial workpiece hardness, temperature, strain and strain rate on flow stress. AISI h13 work tool steel was chosen to verify this methodology. The proposed flow stress model demonstrates a good agreement with data collected from published experiments. Therefore, the proposed model can be used to predict the corresponding flow stress-strain response of AISI h13 work tool steel with variation of the initial workpiece hardness in hard machining.

关键词： flow stress model hard machining AISI h13 work tool steel

Concentration and retention of ascorbic acid,carotenoids,and sugars in fresh-cut lettuce in modified atmosphere packaging

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horticultural Plant journal 2025年第1期11卷 303-313页

作者： jinita Sthapit Kandel Ivan Simko ryan j.hayes Beiquan Mou U.S.Department of Agriculture Agricultural Research ServiceSam Farr United States Crop Improvement and Protection Research Center1636 E.Alisal StreetSalinasCA93905USA U.S.Department of Agriculture Agricultural Research ServiceForage Seed and Cereal Research Unit3450 SW Campus WayCorvallisOR97331USA U.S.Department of Agriculture Agricultural Research ServiceSunflower and Plant Biology Research1616 Albrecht Blvd NFargoND58102USA

Fresh-cut lettuce is widely used in ready-to-eat salads sold in modified atmosphere packages (MAP).Even in MAP,fresh-cut lettuce has short shelf life that results in loss of *** cultivars exhibit genetic variation for shelf life in MAP,but their variation for nutrient retention is not *** accessions were evaluated for initial content of ascorbic acid (AsA),carotenoids,and sugars and their retention in *** with high content and/or good retention of one or more nutrients were *** romaine accession ‘Floricos’ had high levels of all the three *** with relatively high retention of all the three nutrients were ‘Salinas 88’,‘Siskiyou’,‘Solar’,SM09A,‘romance’,and ‘Green Towers’.romaine cultivars,‘Balady Barrage’,‘Green Towers’,and ‘Darkland’ had relatively high initial levels of all tested nutrients and good rate of their *** was no clear correlation between initial AsA/carotene concentrations and their retention rates,suggesting that besides content,retention of nutrients should also be a breeding target in a lettuce nutritional improvement *** analyses with the Pearson's correlation coefficient determined a negative relationship between tissue deterioration(AUDePS) and retention of all tested nutrients[r of-0.52 (Pr AsA,-0.27 (Pr total carotene,and-0.59 (Pr total sugars],suggesting that an increase in tissue deterioration intensifies nutrient ***-sense heritability (h^(2)) across the experiments was0.15 for AsA,0.23 for total carotene,and 0.50 for total *** of germplasm with high nutrient content,extended shelf life and good nutrient retention provides valuable information for the lettuce industry and associated breeding programs.

关键词： Lettuce Shelf life Nutrient retention Ascorbic acid Carotene Sugars