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Temporal and elevation trends in rainfall erosivity on a 149 km2watershed in a semi-arid region of the American Southwest

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International Soil and Water conservation Research 2015年第2期3卷 77-85页

作者： Mark A.Nearingn carl L.Unkrich dave c.goodrich Mary H.Nichols Tim O.Keefer USDA-ARS Southwest Watershed Research center 2000 E Allen RoadTucsonAZ 85719USA

Temporal changes in rainfall erosivity can be expected to occur with changing climate and because rainfall amounts areknown to bein pait of afunction of elevation erosivity can be expected to be influenced by elevation as *** is particularly truein mountainous regions such as are found over much of the westem United *** objective of this study was to identify temporal and elevation trends in rainfall erosivity on a 149km^(2)(58 miles)watershed in a semi-arid region of southeastem Arizona Data from 84 rain gages forthe years 19602012 at elevations ranging from 1231 to 1644 m(40385394 ft)were used in the *** average annual erosivity over the watershed as a whole was 1104 MJ mm ha^(-1)h^(-1)yr^(-1)(65 hundreds of foot ton inch acrei h^(-1)yr^(-1)),and ranged from approximately 950 to 1225 MJ mm ha^(-1)h^(-1)yr^(-1)(56-72 hundreds of foot ton inch acre^(-1)h^(-1)yr^(-1)),with a statistical trend showing greater erosivity af the higher elevations No statistically significant temporal changes in annual or summer erosivities were *** result stands in contrast to fecent modeling studies of runoff and erosion in the area based on downscaled GcM information that project significant levels of erosivity changes over coming *** results are consistent with known orographic rainfall effects,but contrast with recent studies that presented projections of significant trends of increasing erosivity in the future based on downscaled GcM outputs for the area The results illustiate the need for testing and developing improved techniques to evaluate future erosion scenarios for purposes of making targeted soil conservation decisions Production and Hosting by Elsevier B.V on behalf of International Research and Training center on Erosion and Sedimentation and china Water and Power Press This is anopen access article under theccBY-Nc-ND licens(http://***/licenses/by-ncnd/4.0/).

关键词： climate change R-factor RUSLE Semiarid Soil erosion Walnut Gulch

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Atlas of precipitation extremes for South America and Africa based on depth-duration-frequency relationships in a stochastic weather generator dataset

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International Soil and Water conservation Research 2023年第4期11卷 726-742页

作者： Andrew Fullhart David c.goodrich Menberu B.Meles Paulo Tarso S.Oliveira cristiano das Neves Almeida Joséc.de Araújo Shea Burns Southwest Watershed Research center USDA-ARS 2000 E.Allen Rd.TucsonAZ85719United States Sustainable Agricultural Water Systems Unit USDA-ARS 239 Hopkins RoadDavisCA95616United States Faculty of Engineering Architecture and Urbanism and GeographyUniversidade Federal de Mato Grosso do SulCampo GrandeMS79070-900Brazil Water Resources and Environmental Engineering Laboratory Universidade Federal da ParaíbaJoao PessoaPB58051-900Brazil Department of Agricultural Engineering campus do Pici Fortaleza Universidade Federal do CearáFortaleza60020-181Brazil

Information about extreme rainfall is lacking in regions of South America and *** study attempts to fill this scientific gap by use of a gridded parameterization for the stochastic weather generator,cLIGEN,to map depth-duration-frequency(DDF)*** of 500-year point-scale precipitation time series generated at each grid point allowed maps of return period precipitation to be produced for a se-lection of sixteen durations ranging from 10-min to 1-year and for nine return periods from 2 to 500 *** generalized extreme value(GEV)probability distribution was fitted for all durations,and given GEV quantiles,an interpolation method was applied to produce maps at 0.1° resolution that better resolve small-scale spatial climate *** addition to uncertainties related to GEV fitting,this study quantifies prediction intervals based on ground *** validation was important for identifying biases in cLIGEN,although uncertainties were not always satisfactorily defined due to sampling design and other *** daily/multi-day durations,100 stations with daily observations and ≥50-year records were selected for validation against the 0.1° cLIGEN map series,resulting in a median and average absolute error of 13%and 16%,*** sub-daily durations,prediction errors were larger *** analogy using available *** established the degree of bias in cUGEN for sub-daily durations,and three records in Brazil with high temporal resolutions were used to confirm that applied bias adjustments resulted in error ranges similar to the daily/multi-day *** atlas is freely available for study of extreme precipitation.

关键词： Africa Depth-duration-frequency Extreme precipitation South America

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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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Evaluation of the cracking and aging susceptibility of asphalt mixtures using viscoelastic properties and master curve parameters

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第1期9卷 106-119页

作者： Runhua Zhang Jo E.Sias Eshan V.dave Department of civil and Environmental Engineering University of New HampshireDurhamNH 03824USA

Aging can significantly affect the performance of asphalt mixtures, causing increase in stiffness, reduction in relaxation capability and increase in cracking susceptibility. It is also well known that fundamental viscoelastic properties are used for design and modelling of asphalt mixtures and pavement structures to addressing rutting, fatigue and thermal cracking concerns. The objective of this paper is to study how the viscoelastic properties of asphalt mixture change over time, and evaluate and identify the cracking and aging susceptibility of asphalt mixtures with different mix variables during material selection and mixture design. Ten mixtures are evaluated using different laboratory conditioning protocols to simulate a range of aging levels in the field. The complex modulus test is then conducted on the lab aged mixtures to measure the viscoelastic properties in order to construct the dynamic modulus and phase angle master curves. The mixture Glover-Rowe(G-Rm) parameter and the shape parameters of the dynamic modulus and phase angle master curves, including inflection point frequency(-β/γ), difference between the glassy modulus and the inflection point modulus(γ), peak value of phase angle(a) and the horizontal position(frequency) of the peak phase angle value(c), are determined and evaluated for the mixtures with different aging conditions and mix variables. The study indicates the ability of the G-Rmparameter and all the master curve shape parameters to capture the effect of different aging conditions on linear viscoelastic mixture properties, as well as the cracking and aging susceptibility of asphalt mixtures.

关键词： Asphalt mixture Viscoelastic properties complex modulus and phase angle master curve Master curve shape parameters Aging susceptibility cracking susceptibility

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Microstructural characteristics and Mechanical Properties of Low-Alloy, Medium-carbon Steels After Multiple Tempering

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 74-88页

作者： Erfan Abbasi Quanshun Luo dave Owens Materials and Engineering Research Institute Sheffield Hallam University Tyzack Machine Knives Ltd

The microstructure and mechanical properties of NicrMoV-and NicrSi-alloyed medium-carbon steels were investigated after multiple tempering. After austenitising, the steels were hardened by oil quenching and subsequently double or triple tempered at temperatures from 250 to 500 °c. The samples were characterised using scanning electron microscopy and X-ray diffraction, while the mechanical properties were evaluated by Vickers hardness testing, V-notched charpy impact testing and tensile testing. The results showed that the retained austenite was stable up to 400 °c and the applied multiple tempering below this temperature did not lead to a complete decomposition of retained austenite in both steels. It was also found that the microstructure, hardness and impact toughness varied mainly as a function of tempering temperature,regardless of the number of tempering stages. Moreover, the impact toughness of NicrMoV steel was rather similar after single/triple tempering at different temperatures, while NicrSi steel exhibited tempered martensite embrittlement after single/double tempering at 400 °c. The observed difference was mainly attributed to the effect of precipitation behaviour due to the effect of alloying additions in the studied steels.

关键词： Medium-carbon steels Multiple tempering Alloying addition Mechanical properties Retained austenite Precipitation behaviour

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Age and outcomes of primary percutaneous intervention for ST elevation myocardial infarction in a tertiary center are we there yet？

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Journal of Geriatric cardiology 2015年第3期12卷 263-269页

作者： Vinoda Sharma Manivannan Srinivasan dave Smith Morriston cardiac center Swansea Wales United Kingdom

BackgroundPrimary 经皮的干预(PPcI ) 是为圣举起的选择的治疗心肌的梗塞(STEMI ) 但是柔韧的证据在老正在缺乏。我们比较了在不同年龄 quartiles 之间的 PPcI 结果(方照 1 c；60 年，方照 2 ≥；60 到 c；70 年... 详细信息

BackgroundPrimary 经皮的干预(PPcI ) 是为圣举起的选择的治疗心肌的梗塞(STEMI ) 但是柔韧的证据在老正在缺乏。我们比较了在不同年龄 quartiles 之间的 PPcI 结果(方照 1 <；60 年，方照 2 ≥；60 到 <；70 年，方照 3 ≥；70 到 <；80 年，方照 4 ≥；80 年).MethodsRetrospective 我们的 Morriston 第三级的心脏的中心(Abertawe 兄弟 Morgannwg 大学健康板) 的观察分析经历了 *** 434 病人，的有 STEMI 的从 2005 ～ 2010 的病人(13%) 57 在方照 4 (≥；80 年) 。在老年 quartiles，病人们多半是更少收到药 eluting stent (DES， P = 0.001 ) 或 glycoprotein IIb/IIIa 禁止者(GPI， P <；0.0001 ) 。年龄的增加与幸存的减少的时间被联系(β；系数：−； 0.192， t：−； 3.70， 95%cI：−； 4.91 到 −； 1.50， P <；0.0001 ) 这是心脏性的吃惊的存在(β；系数：−； 0.194， t = 3.77， 95%cI：−； 5.26 到 −； 1.65， P <；0.0001 ) 。GPI 的使用与幸存的增加的时间被联系(β；系数：0.138， t = 2.82， 95%cI：1.58-8.58， P = 0.005 ) 但是老年 quartiles 多半是更少收到 GPI (P <；0.0001 ) 。在里面医院死亡(1.8% 方照 1， 3.6% 方照 2， 10.9% 方照 3 和 12.3% 方照 4， P = 0.002 ) 并且 1 年的死亡(5.4% 方照 1， 5.5% 方照 2， 16.8% 方照 3 和 24.6% 方照 4， P <；0.0001，分别地) 在老年 *** 是显著地更高的短术语和中间的学期死亡被看见在在 PPcI 以后老。年龄和心脏性的吃惊是预示的因素。干预不应该独自基于年龄，关于预示的因素的了解能帮助改进管理。

关键词：介入治疗年龄预后分位数可信区间 PcI 老年人 GPI

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Accelerating material design with the generative toolkit for scientific discovery

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npj computational Materials 2023年第1期9卷 1649-1654页

作者： Matteo Manica Jannis Born Joris cadow Dimitrios christofidellis Ashish dave Dean clarke Yves Gaetan Nana Teukam Giorgio Giannone Samuel c.Hoffman Matthew Buchan Vijil chenthamarakshan Timothy Donovan Hsiang Han Hsu Federico Zipoli Oliver Schilter Akihiro Kishimoto Lisa Hamada Inkit Padhi Karl Wehden Lauren McHugh Alexy Khrabrov Payel Das Seiji Takeda John R.Smith IBM Research Europe-Zurich RüschlikonSwitzerland IBM Research-UK HursleyUK IBM Research-Yorktown Heights New YorkUSA IBM Research-Tokyo TokyoJapan IBM Research-Almaden San JoseUSA

With the growing availability of data within various scientific domains,generative models hold enormous potential to accelerate scientific *** harness powerful representations learned from datasets to speed up the formulation of novel hypotheses with the potential to impact material discovery *** present the Generative Toolkit for Scientific Discovery(GT4SD).This extensible open-source library enables scientists,developers,and researchers to train and use state-of-the-art generative models to accelerate scientific discovery focused on organic material design.

关键词： enable scientific formulation

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在海上航运中用于位置感知管理和控制系统的可重用c++类的开发(英文)

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Journal of Marine Science and Application 2012年第4期11卷 504-510页

作者： Dhiren dave Sanjay Nalbalwar Ashok Ghatol Department of Electronics & Telecommunication Engineering Dr. Babasaheb Ambedkar Technological University

Location aware management and location based automation are fast upcoming technologies which are facilitated by availability of reliable, accurate, and cheap global positioning systems and location based services. This paper discusses the development of c++ classes, which may be used for development of software for location aware management and control, specifically in merchant shipping, so as to provide improved safety, increased automation, prevention of pollution and reducing the work burden of the crew. The GPS is used in conjunction with the regionally accessible nested global shorelines (RANGS) dataset for this purpose. The design of two main c++ classes named cShorelines and cGPSInput have been discussed. A control system mandatory on all oil-tankers above 150 GRT (and few other vessels) called ODMcS has been made location aware using the novel software developed and the results obtained have been critically examined and presented.

关键词： GPS Location Aware control ODMcS RANGS

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Antioxidant potential and physicochemical properties of protein hydrolysates from body parts of North Atlantic sea cucumber(cucumaria frondosa)

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Food Production, Processing and Nutrition 2021年第1期3卷 48-69页

作者： Tharindu R.L.Senadheera Deepika dave Fereidoon Shahidi Department of Biochemistry Memorial University of NewfoundlandSt.John’sNL A1B 3X9Canada Marine Bioprocessing Facility Centre of Aquaculture and Seafood DevelopmentFisheries and Marine InstituteMemorial University of NewfoundlandSt.John’sNL A1C 5R3Canada

Protein hydrolysates were prepared from North Atlantic sea cucumber(cucumaria frondosa)body wall(BW),and processing by-product flower(FL)and internal organs(IN).Sea cucumber proteins from these three tissues were hydrolysed with selected endopeptidases and *** enzymes used were Alcalase(A),and corolase(c)as endopeptidases and Flavourzyme(F)with both endo-and exopeptidase *** were employed individually or in combination under controlled *** hydrolysates so prepared were subsequently analysed for their antioxidant potential and functionalities in food systems for the first *** treated with the combination of A and F exhibited the highest radical scavenging activity against DPPH and ABTS *** highest metal chelation activity was observed for samples hydrolysed with the combination of enzymes(c+F and A+F).All treatments inhibited beta-carotene bleaching in an oil-in-water emulsion and TBARS production in a meat model *** addition,sea cucumber protein hydrolysates were more than 75%soluble over a pH range of 2–*** proteins were also effective in enhancing water holding capacity in a meat model system compared to their untreated *** amino acids of sea cucumber protein hydrolysates had desirable profiles with glutamic acid as the predominant component in samples *** findings demonstrate the desirable functionalities of hydrolysates from North Atlantic sea cucumber and their potential for use as functional food ingredients.

关键词： Sea cucumber Protein hydrolysates Antioxidant activity Physicochemical properties

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Numerical investigation of the hydraulic fracturing mechanisms in oil sands

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Underground Space 2021年第2期6卷 195-216页

作者： Siavash Taghipoor Morteza Roostaei Arian Velayati Atena Sharbatian dave chan Alireza Nouri Department of civil and Environmental Engineering University of AlbertaCanada KGHM International 1010 Lorne StSudburyON P3C 4R9Canada RGL Reservoir Management Inc. 690842 StLeducAB T9E 0R8Canada

This paper presents a numerical investigation of hydraulic fracturing in oil sands during cold water injection by considering the aspects of both geomechanics and reservoir fluid *** to previous studies,the low shear strengths of unconsolidated or weakly consolidated sandstone reservoirs significantly influence the hydraulic fracturing ***,classical hydraulic fracture models cannot simulate the fracturing process in weak sandstone *** the current numerical models,the direction of a tensile fracture is predetermined based on in situ stress ***,the potential transformation of a shear fracture into a tensile fracture and the potential reorientation of a tensile fracture owing to shear banding at the fracture tip have not yet been addressed in the *** this study,a smeared fracture technique is employed to simulate tensile and shear fractures in oil *** model used combines many important fracture features,which include the matrix flow,poroelasticity and plasticity modeling,saturation-dependent permeability,gradual degradation of the oil sands as a result of dilative shear deformation,and the tensile fracturing and shear failure that occur with the simultaneous enhancement of ***,sensitivity analyses are also performed with respect to the reservoir and geomechanical parameters,including the apparent tensile strength and cohesion of the oil sands,magnitude of the minimum and maximum principal stress,absolute permeability and elastic modulus of the oil sands and ramp-up *** these analyses are performed to clarify the influences of these parameters on the fracturing response of the oil sands.

关键词： Smeared fracture Hydraulic fracturing Numerical simulation Oil sand

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