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Spatial variability of soil water erosion:Comparing empirical and intelligent techniques

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Geoscience Frontiers 2023年第1期14卷 1-16页

作者： ali Golkarian Khabat Khosravi Mahdi Panahi john j.Clague Department of Watershed Management Engineering Ferdowsi University of MashhadMashhadIran Department of Earth and Environment Florida International UniversityMiamiUSA Division of Smart Regional Innovation Kangwon National UniversityGangwon-do 24341Republic of Korea Department of Earth Sciences Simon Fraser UniversityBurnabyBCCanada

Soil water erosion(SWE)is an important global hazard that affects food availability through soil degradation,a reduction in crop yield,and agricultural land abandonment.A map of soil erosion susceptibility is a first and vital step in land management and soil *** machine learning(ML)algorithms optimized using the Grey Wolf Optimizer(GWO)metaheuristic algorithm can be used to accurately map SWE *** optimized algorithms include Convolutional Neural Networks(CNN and CNN-GWO),Support Vector Machine(SVM and SVM-GWO),and Group Method of Data Handling(GMDH and GMDH-GWO).Results obtained using these algorithms can be compared with the well-known Revised Universal Soil Loss Equation(RUSLE)empirical model and Extreme Gradient Boosting(XGBoost)ML tree-based *** apply these methods together with the frequency ratio(FR)model and the Information Gain Ratio(IGR)to determine the relationship between historical SWE data and controlling geo-environmental factors at 116 sites in the Noor-Rood watershed in northern *** SWE geo-environmental factors are classified in topographical,hydro-climatic,land cover,and geological *** next divided the SWE sites into two datasets,one for model training(70%of the samples=81 locations)and the other for model validation(30%of the samples=35 locations).Finally the model-generated maps were evaluated using the Area under the Receiver Operating Characteristic(AU-ROC)*** results show that elevation and rainfall erosivity have the greatest influence on SWE,while soil texture and hydrology are less *** CNN-GWO model(AU-ROC=0.85)outperformed other models,specifically,and in order,SVR-GWO=GMDH-GWO(AUC=0.82),CNN=GMDH(AUC=0.81),SVR=XGBoost(AUC=0.80),and *** on the RUSLE model,soil loss in the Noor-Rood watershed ranges from 0 to 2644 t ha^(-1)yr^(-1).

关键词： Soil erosion Machine learning RUSLE CNN-GWO Iran

THE IMPROVEMENT IN FRICTION AND WEAR RESISTANCE FORTa and Ta+C IMPLANTED Cr12 STEEL

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Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 137-140页

作者： j.H.Yang T.H.Zhang Nantong Inst of Technology Nantong China

Ta and C ions extracted from a MEVVA ion source were implanted into Cr12 steel, with an implantation dose of (1-5)ｘ1017cm-2, extraction acceleration 42kV, and average ion beam flux about 20-50μA·cm-2. Rutherford backscattering spectrum (RBS) was used to measure the surface composition after Ta and Ta+C implantation. Analysis of phase formed by Ta and C implantation was carried out by X-ray diffraction analysis (XRD). Experiment results showed that the wear rate of the implanted layer dropped 40% for Ta ion implantation and by a factor of 2.7 for Ta+C dual ion implantation. Ta+C dual ion implantation was found to reduce the friction coefficient of Cr12 steel. The wear mechanisms of the implanted layer were discussed.

关键词： wear resistance Cr12 steel ion implantation

Swampland dS conjecture in mimetic f(R,T)gravity

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Communications in Theoretical Physics 2022年第8期74卷 101-115页

作者： S Noori Gashti j Sadeghi S Upadhyay M R alipour Department of Physics Faculty of Basic SciencesUniversity of Mazandaran PO Box 47416-95447BabolsarIran Department of Physics K.L.S.CollegeNawadaBihar 805110India Department of Physics Magadh UniversityBodh GayaBihar 824234India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PuneMaharashtra 411007India School of Physics Damghan UniversityDamghan ***Iran

In this paper,we study a theory of gravity called mimetic f(R,T)in the presence of swampland dS *** this purpose,we introduce several inflation solutions of the Hubble parameter H(N)from f(R,T)=R+δT gravity model,in which R is Ricci scalar,and T denotes the trace of the energy–momentum ***,δand N are the free parameter and a number of e-fold,*** we calculate quantities such as potential,Lagrange multiplier,slow-roll,and some cosmological parameters such as nsand *** we challenge the mentioned inflationary model from the swampland dS *** discuss the stability of the model and investigate the compatibility or incompatibility of this inflationary scenario with the latest Planck observable data.

关键词： mimetic f(R,T)gravity Lagrange multiplier swampland conjecture

胰腺神经内分泌肿瘤门静脉期CT肿瘤/胰腺实质增强比的预后价值

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国际医学放射学杂志 2023年第3期 369-370页

作者： H.j.Park H.j.Kim j.H.Kim S.Y.Kim S.H.Choi j.H.Byun 程欣

摘要目的评估胰腺神经内分泌肿瘤（PanNEN）病人门静脉期CT肿瘤-胰腺实质增强比（CER on PVP）在预后方面的价值，并将其与当前常见的分级和分期系统进行比较。方

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Quintessence Cosmology with an Effective Λ-Term in Lyra Manifold

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Chinese Physics Letters 2015年第10期32卷 174-177页

作者： KhurshudyanM. Pasqua A Sadeghi j. Farahani H Chair of Theoretical Physics and Physics Teaching Methods Armenian State Pedagogical University Yerevan 375010 Republic of Armenia Department of Physics University of Trieste Trieste 234127 Italy Department of Physics University of Mazandaran Babolsar 47416-95447 Iran

We study quintessence cosmology with an effective A-term in Lyra manifold. We consider three different models by choosing variable A depending on time, the Hubble parameter and the energy density of dark matter and dark energy. Dark energy is assumed as quintessence which interacts with the dark matter. Using numerical analysis we investigate the behavior of cosmological parameters in three different models and compare our results with observational data. State-finder diagnostic is also performed for all models.

关键词： Quintessence Cosmology with an Effective Term in Lyra Manifold

A MONTE CARLO SIMULATION OF SECONDARY ELECTRON AND BACKSCATTERED ELECTRON IMAGES IN SCANNING ELECTRON MICROSCOPY

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 351-355页

作者： H.M.Li Z.j.Ding HefeiNationalLaboratoryforPhysicalSciencesatMicroscaleandDepartmentofPhysics UniversityofScienceandTechnologyofChinaHefei230026China

A new parallel Monte Carlo simulation method of secondary electron (SE) and back scattered electron images (BSE) of scanning electron microscopy (SEM) for a com plex geometric structure has been developed. This paper describes briefly the si mulation method and the modification to the conventional sampling method for the step length. Example simulation results have been obtained for several artifici al structures.

关键词： Monte Carlo SEM secondary electrons backscattered electrons,

Coating behavior and surface hardening of Pd_(77)Cu_6Si_(17) thin film metallic glass on AZ31 magnesium alloy

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 898-905页

作者： X.H.DU Y.C.CHANG H.j.PEI B.Y.CHEN M.C.KUO j.C.HUANG School of Materials Sciences and Engineering Shenyang Aerospace University Department of Materials and Optoelectronic Science National Sun Yat-Sen University Department of Materials Engineering Kun Shan University

Pd77Cu6Si17(PCS) thin film metallic glasses(TFMGs) with high glass forming ability and hardness were selected as a hard coating for improving the surface hardness of AZ31 magnesium alloy. Both microindentation and nanoindentation tests were conducted on specimens with various PCS film thicknesses from 30 to 2000 nm. The apparent hardness and the relative indentation depth(β) were integrated using a quantitative model. The interaction parameters involved and relative hardness values were extracted from iterative calculations. According to the results, surface hardness can be enhanced greatly by PCS TFMGs in the shallow region, followed by gradual decrease with increasing β ratio. In addition, specimens with thinner coatings(e.g., 200nm) showed greater substrate-film interaction and those with thick coatings(e.g., 2000nm) became prone to film cracking. The optimum TFMG coating thickness in this study was estimated to be around 200 nm.

关键词： Thin film metallic glass(TFMG) Magnesium alloy Sputtering process Nanoindentation Coating thickness

The practice of mine ventilation engineering

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International journal of Mining Science and Technology 2015年第2期25卷 165-169页

作者： Wallace Keith Prosser Brian Stinnette j.Daniel Mine Ventilation Services Inc.

The practice of ventilation is continually evolving with new technological advances developed in the mining *** recent years the advances in diesel engine technologies,ventilation modeling software,and ventilation management capacities have redefined the historical methods used to evaluate *** advances re-evaluate previous methods used to calculate the airflow requirements for the dilution of diesel exhaust *** software has become an integral part of planning and developing ventilation systems in partnership with graphical mine design software packages to generate realistic representations of the *** advances in ventilation control strategies through remote sensors and monitoring capabilities have been developed to results in cost *** there has been much advancement in mine ventilation technology,the practices and basic ventilation principals enacted through the ventilation engineer cannot be placated with technological advances only.

关键词：矿井通风工程实践技术进步合作伙伴关系建模软件评估系统柴油发动机矿业发展

Synthesis, characterization and oxidative activity of heteropolyanion pillared layered compound

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Chinese Science Bulletin 1997年第11期42卷 914-918页

作者： He, QL Gao, j Hu, CW Wang, EB NE NORMal UNIV DEPT CHEMCHANGCHUN 130024PEOPLES R CHINA

TRANSITION element trisubstituted and Ln bi-（1:11）series heteropolyanion with Keggin struc-ture are excellent catalyst with oxidizing *** they have some shortcomingssuch as poor stability and impossible recycle use when they are used in homogeneous ***（An-）,among hydroxides（LDHS）-like layers,having a general formula[M1-x2+Mx3+-

关键词： heteropolyanion pillared layered compound synthesis oxidative activity.