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Towards global coverage of gridded parameterization for CLImate GENerator(CLIGEN)

Big Earth Data 2024年第1期8卷 142-165页

作者： Andrew T.Fullhart Guillermo E.ponce-Campos Menberu B.Meles ryan p.mcgehee Haiyan Wei Gerardo Armendariz Shea Burns David C.Goodrich Southwest Watershed Research Center USDA-ARS TucsonAZUSA School of Natural Resources and the Environment University of ArizonaTucsonAZUSA Sustainable Agricultural Water Systems Unit USDA-ARS DavisCAUSA Agricultural and Biosystems Engineering Iowa State UniversityAmesIAUSA

Stochastic weather generators create time series that reproduce key weather dynamics present in long-term *** dataset detailed herein is a large-scale gridded parameterization for CLImate GENerator(CLIGEN)that fills spatial gaps in the coverage of existing regional CLIGEN parameterizations,thereby obtaining near-global availability of combined *** dataset primarily covers countries north of 40°latitude with 0.25°spatial *** CLIGEN parameters were estimated based on 20-year records from four popular global climate *** parameters were statistically downscaled to estimate point-scale values,while point-scale temperature and solar radiation parameters were approximated by direct calculation from high-resolution *** parameter values were used in some cases,such as with wind ***-validation was done to assess the downscaling approach for six precipitation parameters using known point-scale values from ground-based CLIGEN *** parameter values were derived from daily accumulation records at 7,281 stations and high temporal resolution records at 609 *** sensitive parameters,monthly average storm accumulation and maximum 30-minute intensity,were shown have RMSE values of 1.48 mm and 4.67 mm hr^(−1),*** precipitation and the annual number of days with precipitation occurrence were both within 5%of ground-based parameterizations,effectively improving climate data availability.

关键词： Agriculture climate hydrology soil erosion stochastic weather generator

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Calibration,validation,and evaluation of the Water Erosion prediction project(WEpp)model for hillslopes with natural runoff plot data

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International Soil and Water Conservation Research 2023年第4期11卷 669-687页

作者： Shuyuan Wang ryan p.mcgehee Tian Guo Dennis C.Flanagan Bernard A.Engel Department of Agricultural&Biological Engineering Purdue UniversityWest LafayetteIN47907USA USDA-Agricultural Research Service National Soil Erosion Research LaboratoryWest LafayetteIN47907USA

The Water Erosion prediction project(WEpp)model has been widely used for estimating runoff and soil *** evaluation of the latest version(version 2021.133)under a range of environmental conditions can provide confidence to its *** objectives of this study were to evaluate the WEpp model for runoff and soil loss predictions using 1159 plot years of rainfall-runoff events data from field experi-mental plots with various climates,soils,topographies,and *** runoff and soil loss predictions were compared to the observations before and after input parameter *** results showed good predictions of runoff and soil loss were obtained with both the uncalibrated and calibrated WEpp model for all considered scales with Nash-Sutcliffe model efficiencies(NSE)over *** calibration of input baseline effective hydraulic conductivity(k_(e)),baseline critical shear stress(τ_(c)),baseline rill erod-ibility(k_(r)),and baseline interrill erodibility(k_(i))improved WEpp model performance with NSE values of 0.98 and 0.91 for average annual runoff and soil loss predictions,*** WEpp model tended to underestimate the runoff and soil loss for large events with runoff over 100 mm and soil loss over 120t/*** event runoff and soil loss predictions(NSE ≥0.4)were obtained for the most common cropping/management systems considered,including corn,cotton,tilled fallow,and wheat after *** study illustrates the most recent WEpp model's performance for runoff and soil loss predictions,and provides a comprehensive set of results.

关键词： WEpp Runoff Soil loss Calibration Validation

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An updated isoerodent map of the conterminous United States

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International Soil and Water Conservation Research 2022年第1期10卷 1-16页

作者： ryan p.mcgehee Dennis C.Flanagan puneet Srivastava Bernard A.Engel Chi-Hua Huang Mark A.Nearing purdue University Agricultural and Biological Engineering225 South University StreetWest LafayetteIN47907USA United States Department of Agriculture-Agricultural Research Service National Soil Erosion Research Laboratory275 S Russell StWest LafayetteIN47907USA University of Maryland Agricultural Experiment StationSymons Hall7998 Regents DriveCollege ParkMD20742-3131USA purdue University Agricultural Administration Building615 West State StreetWest LafayetteIN47907-2053USAUnited States Department of Agriculture-Agricultural Research ServiceNational Soil Erosion Research Laboratory275 S Russell StWest LafayetteIN47907USA United States Department of Agriculture-Agricultural Research Service Southwest Watershed Research Center2000 E Allen RdTucsonAZ85719USA

Maps of erosivity,which are also commonly referred to as isoerodent maps,have played a critical role in soil conservation efforts in the United States and around the *** available erosivity maps for the United States are either outdated,conflict with erosivity benchmarking studies,or utilized less advanced spatial mapping ***,it is possible that the same underlying issues with US maps are impacting global maps as *** this study,we used more than 340015-min,fixed-interval precipitation gauges to update the isoerodent map of the conterminous United *** values were interpolated using universal kriging under several spatial model configurations and *** optimal spatial model was selected based on which result had the lowest sample variogram ***,erosivity,and erosivity density maps were compared to existing *** average annual and annual erosivity results were compared to high-quality erosivity benchmarking *** values from both RUSLE2 and panagos et al.(2017)were generally lower in the eastern United States and mixed in the western United States compared to our *** effects resulted in much greater erosivity differences in this study as compared to prior *** comparisons revealed that erosivity maps from this study and others were lower than the benchmark by 14%or more(up to 38%).These findings suggest current practices of storm omission and intensity dampening correction need to be revisited,especially in locations with relatively low-to-moderate rainfall erosivity such as the Midwest or Northeast United States,for example.

关键词： Erosion index Erosivity United States USLE RUSLE2 Soil loss

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A WEpp-Water Quality model for simulating nonpoint source pollutants in nonuniform agricultural hillslopes:Model development and sensitivity

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International Soil and Water Conservation Research 2023年第3期11卷 455-469页

作者： ryan pmcgehee Dennis CFlanagan Bernard AEngel Department of Agricultural and Biological Engineering Purdue University225 South University StreetWest LafayetteIN47907USA DA-Agricultural Research Service National SoilErosion Research Laboratory275 South Russell StreetWest LafayetteIN4797USA

The Water Erosion prediction project(WEpp)model code was modified extensively to support the simulation of nonpoint source(NpS)pollutant sourcing and transport in nonuniform hillslopes based on NpS science from the Soil and Water Assessment Tool(SWAT).This was accomplished utilizing WEpp's overland flow element(OFE)in place of SWAT's hydrologic response unit(HRU)construct which enabled more physically plausible routing within a *** addition,several improvements to the NpS code base were *** include:free-source format,modern-Fortran conventions,minor enhancements to NpS model science,and code *** manuscript documents all model development activities,presents a comparison of relevant WEpp and WEpp-WQ code bases,and performs a local sensitivity analysis of the final model code for the most important input parameters and *** results indicated that the model performed as expected according to its design and provided important insights for potential subsequent validation studies.

关键词： WEpp SWAT WEpp-WQ Water quality Nonpoint Sensitivity

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Gridded 20-year climate parameterization of Africa and South America for a stochastic weather generator (CLIGEN)

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Big Earth Data 2023年第2期7卷 349-374页

作者： Andrew Fullhart Guillermo E.ponce-Campos Menberu B.Meles ryan p.mcgehee Gerardo Armendariz paulo Tarso S.Oliveira Cristiano Das Neves Almeida José C.de Araújo Werner Nel David C.Goodrich Southwest Watershed Research Center USDA-ARS TucsonAZUSA School of Natural Resources and the Environment University of ArizonaTucsonAZUSA Sustainable Agricultural Water Systems Unit USDA-ARS DavisCAUSA Agricultural and Biological Engineering Purdue UniversityWest LafayetteINUSA Faculty of Engineering Architecture and Urbanism and GeographyFederal University of Mato Grosso do Sul(UFMS)Campo GrandeMSBrazil Water Resources and Environmental Engineering Laboratory Federal University of ParaíbaJoao PessoaPBBrazil Federal University of Fortaleza Department of Agricultural EngineeringFortalezaBrazil Department of Geography and Environmental Science University of Fort HareAliceSouth Africa

CLIGEN is a stochastic weather generator that creates statistically representative timeseries of daily and sub-daily point-scale weather variables from observed monthly statistics and other parameters. CLIGEN precipitation timeseries are used as climate input for various risk-assessment modelling applications as an alternative to observe long-term, high temporal resolution records. Here, we queried gridded global climate datasets (TerraClimate, ERA5, GpM-IMERG, and GLDAS) to estimate various 20-year climate statistics and obtain complete CLIGEN input parameter sets with coverage of the African and South American continents at 0.25 arc degree resolution. The estimation of CLIGEN precipitation parameters was informed by a ground-based dataset of >10,000 locations worldwide. The ground observations provided target values to fit regression models that downscale CLIGEN precipitation input parameters. Aside from precipitation parameters, CLIGEN’s parameters for temperature, solar radiation, etc. were in most cases directly calculated according to the original global datasets. Cross-validation for estimated precipitation parameters quantified errors that resulted from applying the estimation approach in a predictive fashion. Based on all training data, the RMSE was 2.23 mm for the estimated monthly average single-event accumulation and 4.70 mm/hr for monthly maximum 30-min intensity. This dataset facilitates exploration of hydrological and soil erosional hypotheses across Africa and South America.

关键词： Climate CLIGEN Africa South America

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Direct-to-indirect mapping for optimal low-thrust trajectories

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Astrodynamics 2024年第1期8卷 27-46页

作者： David Ottesen ryan p.Russell Department of Aerospace Engineering and Engineering Mechanics The University of Texas at AustinAustinTexas78712USA

Optimal,many-revolution spacecraft trajectories are challenging to solve.A connection is made for a class of models between optimal direct and indirect *** transfers that minimize thrust-acceleration-squared,primer vector theory maps direct,many-impulsive-maneuver trajectories to the indirect,continuous-thrust-acceleration *** mapping algorithm is independent of how the direct solution is obtained and requires only a solver for a boundary value problem and its partial derivatives.A Lambert solver is used for the two-body problem in this *** mapping is simple because the impulsive maneuvers and co-states share the same linear space around an optimal *** numerical results,the direct coast-impulse solutions are demonstrated to converge to the indirect continuous solutions as the number of impulses and segments *** two-body design space is explored with a set of three many-revolution,many-segment examples changing semimajor axis,eccentricity,and *** first two examples involve a small change to either semimajor axis or eccentricity,and the third example is a transfer to geosynchronous *** a single processor,the optimization runtime is seconds to minutes for revolution counts of 10 to 100,and on the order of one hour for examples with up to 500 *** of these thrust-acceleration-squared solutions are good candidates to start a homotopy to a higher-fidelity minimization problem with practical constraints.

关键词： direct optimization indirect optimization impulsive maneuvers Lambert's problem two-body dynamics primer vectortheory

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Machine learning-guided accelerated discovery of structure-property correlations in lean magnesium alloys for biomedical applications

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Journal of Magnesium and Alloys 2024年第6期12卷 2267-2283页

作者： Sreenivas Raguraman Maitreyee Sharma priyadarshini Tram Nguyen ryan McGovern Andrew Kim Adam J.Griebel paulette Clancy Timothy p.Weihs Department of Materials Science and Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Hopkins Extreme Materials Institute Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Department of Chemical and Biomolecular Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Translational Tissue Engineering Center Johns Hopkins School of Medicine400 N BroadwayBaltimore21231MDU.S.A Department of Biomedical Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Research and Development Fort Wayne Metals Research ProductsLLC9609 Ardmore AveFort Wayne46809INU.S.A Department of Mechanical Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A

Magnesium alloys are emerging as promising alternatives to traditional orthopedic implant materials thanks to their biodegradability,biocompatibility,and impressive mechanical ***,their rapid in-vivo degradation presents challenges,notably in upholding mechanical integrity over *** study investigates the impact of high-temperature thermal processing on the mechanical and degradation attributes of a lean Mg-Zn-Ca-Mn alloy,*** rapid,cost-efficient characterization methods like X-ray diffraction and optical microscopy,we swiftly examine microstructural changes post-thermal *** pearson correlation coefficient analysis,we unveil the relationship between microstructural properties and critical targets(properties):hardness and corrosion ***,leveraging the least absolute shrinkage and selection operator(LASSO),we pinpoint the dominant microstructural factors among closely correlated *** findings underscore the significant role of grain size refinement in strengthening and the predominance of the ternary Ca_(2)Mg_(6)Zn_(3)phase in corrosion *** suggests that achieving an optimal blend of strength and corrosion resistance is attainable through fine grains and reduced concentration of ternary *** thorough investigation furnishes valuable insights into the intricate interplay of processing,structure,and properties in magnesium alloys,thereby advancing the development of superior biodegradable implant materials.

关键词： Magnesium alloys Machine learning Corrosion Mechanical properties Rapid characterization

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Childhood opportunity and appropriate use of child safety restraints in motor vehicle collisions

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World Journal of pediatric Surgery 2024年第2期7卷 142-149页

作者： Stephanie Y Chen Iris Garcia Shadassa Ourshalimian Chantel Lowery pradip p Chaudhari ryan G Spurrier pediatric Surgery Children's Hospital Los AngelesLos AngelesCaliforniaUSA Injury prevention program Children's Hospital Los AngelesLos AngelesCaliforniaUSA Emergency and Transport Medicine Children's Hospital Los AngelesLos AngelesCaliforniaUSA pediatrics University of Southern California Keck School of MedicineLos AngelesCaliforniaUSA Surgery University of Southern California Keck School of MedicineLos AngelesCaliforniaUSA

Objectives Safety restraints reduce injuries from motor vehicle collisions(MVCs)but are often improperly applied or not *** Childhood Opportunity Index(COI)reflects social determinants of health and its study in pediatric trauma is *** hypothesized that MVC patients from low-opportunity neighborhoods are less likely to be appropriately *** A retrospective cross-sectional study was performed on children/adolescents≤18 years old in MVCs between January 1,2011 and December 31,*** were identified from the Children's Hospital Los Angeles trauma *** outcome was safety restraint use(appropriately restrained,not appropriately restrained).COI levels by home zip codes were stratified as very low,low,moderate,high,and very *** regression controlling for age identified factors associated with safety restraint *** Of 337 patients,73.9%were appropriately restrained and 26.1%were not appropriately *** with appropriately restrained patients,more not appropriately restrained patients were from low-COI(26.1%vs 20.9%),high-COI(14.8%vs 10.8%)and very high-COI(10.2%vs 3.6%)*** analysis demonstrated no significant associations in appropriate restraint use and *** was a non-significant trend that children/adolescents from moderate-COI neighborhoods were more likely than those from very low-COI neighborhoods to be appropriately restrained(OR=1.82,95%CI 0.78,4.28).Conclusion Injury prevention initiatives focused on safety restraints should target families of children from all neighborhood types.

关键词： MVC restrained neighborhood

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Temporally preserving Latent Variable Models:Offline and Online Training for Reconstruction and Interpretation of Fault Data for Gearbox Condition Monitoring

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Journal of Dynamics, Monitoring and Diagnostics 2024年第2期3卷 156-177页

作者： ryan Balshaw p.Stephan Heyns Daniel N.Wilke Stephan Schmidt Center for Asset Integrity Management Department of Mechanical and Aeronautical EngineeringUniversity of PretoriaPretoriaSouth Africa

Latent variable models can effectively determine the condition of essential rotating machinery without needing labeled *** models analyze vibration data via an unsupervised learning *** preservation is necessary to obtain an informative latent manifold for the fault diagnosis *** a temporalpreserving context,two approaches exist to develop a condition-monitoring methodology:offline and *** latent variable models,the available training modes are not *** many traditional methods use offline training,online training can dynamically adjust the latent manifold,possibly leading to better fault signature extraction from the vibration *** study explores online training using temporal-preserving latent variable *** online training,there are two main methods:one focuses on reconstructing data and the other on interpreting the data *** are considered to evaluate how they diagnose faults over *** two experimental datasets,the study confirms that models from both training modes can detect changes in machinery health and identify faults even under varying ***,the complementarity of offline and online models is emphasized,reassuring their versatility in fault *** the implications of the training approach and the available model formulations is crucial for further research in latent variable modelbased fault diagnostics.

关键词： Condition monitoring unsupervised learning latent variable models temporal preservation training approaches

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Characterizing objective and self-report habitual physical activity and sedentary time in outpatients with an acquired brain injury

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Sports Medicine and Health Science 2024年第4期6卷 338-343页

作者： Liam p.pellerine Katerina Miller ryan J.Frayne Myles W.O'Brien Division of Kinesiology School of Health and Human PerformanceFaculty of HealthDalhousie UniversityHalifaxNova ScotiaCanada Acquired Brain Injury NeuroCommons Nova Scotia Health AuthorityHalifaxNova ScotiaCanada School of physiotherapy(Faculty of Health)&Department of Medicine(Faculty of Medicine) Dalhousie UniversityHalifaxNova ScotiaCanada Geriatric Medicine Research Dalhousie University&Nova Scotia HealthHalifaxNova ScotiaCanada Centre de Formation Medicale Du Nouveau-Brunswick New Brunswick&Department of MedicineUniversite de SherbrookeSherbrookeQuebecCanada

Outpatients with an acquired brain injury(ABI)experience physical,mental,and social *** can be classified into two subgroups based on mechanism of injury:mild traumatic brain injury(mTBI;e.g.,concussion)and other ABI(e.g.,stroke,brain aneurysm,encephalitis).Our understanding of habitual activity levels within ABI populations is limited because they are often collected using self-report *** purpose of this study was to,1)describe the habitual activity levels of outpatients with ABI using objective and self-report monitoring,and 2)compare the activity levels of outpatients with mTBI *** *** outpatients with other ABI(mean±standard deviation:[58±13]years,9 females)and 12 outpatients with mTBI([48±11]years,9 females)wore a thigh-worn activpAL 24 h/day(h/day)for *** with ABI averaged(6.0±2.3)h/day of upright time,(10.6±2.2)h/day of sedentary time,(5.6±2.7)h/day in prolonged sedentary bouts>1 h,(5960±3037)steps/day,and(11±13)minutes/day(min/day)of moderate-vigorous physical activity(MVpA).There were no differences between activpAL-derived upright,sedentary,prolonged sedentary time,and physical activity between the mTBI and other ABI groups(all,p>0.31).Outpatients with ABI overestimated their MVpA levels(t138 min/week)and underestimated sedentary time(-4.3 h/day)compared to self-report(all,ppite self-reporting high activity levels,outpatients with ABI objectively exhibit highly inactive and sedentary *** habitual movement behaviours of our sample did not differ by mechanism of injury(i.e.,mTBI versus other ABI).Targeting reductions in objectively measured sedentary time are needed to progressively improve the habitual movement behaviours of outpatients with ABI.

关键词： Accelerometry Stroke Brain aneurysm Encephalitis Mild traumatic brain injury Rehabilitation

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