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The El Niño-Southern Oscillation (ENSO) Effects on Cowpea and Winter Wheat Yields in the Semi-Arid region of the Southern US

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Agricultural Sciences 2023年第2期14卷 154-175页

作者： Prem Woli Gerald r. Smith charles r. long Francis M. rouquette Jr. Texas A&M AgriLife research Center Overton TX USA

Information is limited on the effects of climate variability on cowpea (Vigna unguiculata L.) and winter wheat (Triticum aestivum L.) yields in the semiarid region of the southern US. Using the Decision Support System for Agrotechnology Transfer (DSSAT) crop model and weather data spanning 81 years, we assessed the impact of El Niño-Southern Oscillation (ENSO) on the grain yields of these crops in the Llano Estacado region of the southern US as affected by cowpea and wheat planting dates and N application rate. Simulated results showed that the El Niño phase of ENSO produced about 30% more yields of mono-cropped cowpea than those produced under the La Niña phase, especially with the cowpeas planted in July. The cowpea yields under El Niño were about 10% more than the 81-year average normal yield, whereas those under La Niña were about 20% less. At the N rates of 0, 50, and 100 kg·ha−1, regardless of wheat planting dates, the El Niño years produced, respectively, about 8%, 40%, and 60% higher wheat yields than those produced in the La Niña years, and about 5%, 20%, and 27% more than the 81-year average normal yield. In the La Niña years, the wheat yields at 0, 50, and 100 kg N ha−1 were, respectively, about 5%, 15%, and 20% less than the normal yield with similar N levels. The impact of ENSO on wheat yields under cowpea-wheat double-cropping systems was significant, especially for the wheat crops planted on October 15 (October 30) or later following the cowpea crops planted in June (July). At zero N, the mono-cropped wheat yields were not impacted by ENSO due to N limitation. However, the double-cropped wheat yields were impacted by ENSO even when no N fertilizer was applied due to high soil N status caused by N transfer from cowpea stover residues and roots. results indicated that management strategies need to be attentive to ENSO forecasts and adjust potential planting dates and N application rates with the ENSO phase to avert risks of crop fa

关键词： Climate Cowpea DSSAT Double-Crop El Niño ENSO Model Semi-Arid Wheat

Enhancing manual P-phase arrival detection and automatic onset time picking in a noisy microseismic data in underground mines

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International Journal of Mining Science and Technology 2018年第4期28卷 683-691页

作者： Mborah charles Ge Maochen Department of Mining and Nuclear Engineering Missouri University of Science and Technology

Accurate detection and picking of the P-phase onset time in noisy microseismic data from underground mines remains a big challenge. reliable P-phase onset time picking is necessary for accurate source location needed for planning and rescue operations in the event of failures. In this paper, a new technique based on the discrete stationary wavelet transform （DSWT）and higher order statist!cs, is proposed for processing noisy data from underground mines. The objectives of this method are to （1） Improve manual detection and tPicking of P-phase onset; and （ii） provide an automatic means of detecting and picking P-phase onset me accurately. The DSWT is first used to filter the signal over several scales. The manual P-phase onset detection and picking are then obtained by computing the signal energy across selected scales with frequency bands that capture the signal of interest. The automatic P-phase onset, on the other hand, is achieved by using skewness- and kurtosis-based criterion applied to selected scales in a time-frequency domain. The method was tested using synthetic and field data from an underground limestone mine. results were compared with results obtained by using the short-term to long-term average （STA/LTA） ratio and that by reference Ge et al. （2009）. The results show that the me!hod provides a more reliable estimate of the P-phase onset arrival than the STA]LTA method when the signal to noise ratio is very low. Also, the results obtained from the field data matched accurately with the results from reference Ge et al. （2009）.

关键词： Manual P-phase detection Automatic onset picking Noisy microseismic data Kurtosis Skewness

Alkali-thermal gasification and hydrogen generation potential of biomass

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 369-378页

作者： Alexander B. Koven Shitang S. Tong ramin r. Farnood charles Q. Jia Department of Chemical Engineering and Applied Chemistry University of Toronto Ontario M5S-3E5 Canada School of Chemistry and Chemical Engineering Wuhan University of Science and Technology Wuhan 430081 China

Generating hydrogen gas from biomass is one approach to lowering dependencies on fossil fuels for energy and chemical feedstock, as well as reducing greenhouse gas emissions. Using both equilibrium simulations and batch experiments with NaOH as a model alkaline, this study established the technical feasibility of converting various biomasses （e.g., glucose, cellulose, xylan and lignin） into H2-rich gas via catalyst-free, alkali-thermal gasification at moderate temperatures （as low as 300℃）. This process could produce more H2 with less carbon-containing gases in the product than other comparable methods. It was shown that alkali-thermal gasification follows CxHyO2 ＋ 2xNaOH ＋（x-z）H20 = （2x＋y/2-z）H2 ＋xNa2CO3, with carbonate being the solid product which is different from the one suggested in the literature. Moreover, the concept of hydrogen genera- tion potential （H2-GP）-the maximum amount of H2 that a biomass can yield, was introduced. For a given biomass CxHyO2, the H2-GP would be （2x ＋ y/2-z） moles of H2. It was demonstrated experimentally that the H2-GP was achievable by adjusting the amounts of H20 and NaOH, temperature and pressure. Keywords hydrogen generation potential, biomass, lignocellulose, alkali-thermal gasification, sodium hydroxide

关键词： hydrogen generation potential biomass lignocellulose alkali-thermal gasification sodium hydroxide

Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková S.Šašek J.Dittrich M.Knapek F.Lukáˇc D.Koutný J.Jaroš r.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SLM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SLM material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the SLM and SPS materials,*** corrosion resistance of the SPS material in 0.1 M NaCl solution was superior to the SLM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SLM *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength Corrosion resistance

Medium-chain fatty acids and monoglycerides as feed additives for pig production:towards gut health improvement and feed pathogen mitigation

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Journal of Animal Science and Biotechnology 2020年第3期11卷 611-625页

作者： Joshua A.Jackman rDean Boyd charles C.Elrod School of Chemical Engineering Sungkyunkwan UniversitySuwon 16419Republic of Korea Hanor Company FranklinKY 42134USA North Carolina State University RaleighNC 27695USA Natural Biologics Inc. NewfieldNY 14867USA Department of Animal Science Cornell UniversityIthacaNY 14853USA.

Ongoing challenges in the swine industry,such as reduced access to antibiotics and virus outbreaks(e.g.,porcine epidemic diarrhea virus,African swine fever virus),have prompted calls for innovative feed additives to support pig ***-chain fatty acids(MCFAs)and monoglycerides have emerged as a potential option due to key molecular features and versatile functions,including inhibitory activity against viral and bacterial *** this review,we summarize recent studies examining the potential of MCFAs and monoglycerides as feed additives to improve pig gut health and to mitigate feed *** molecular properties and biological functions of MCFAs and monoglycerides are first introduced along with an overview of intervention needs at different stages of pig *** latest progress in testing MCFAs and monoglycerides as feed additives in pig diets is then presented,and their effects on a wide range of production issues,such as growth performance,pathogenic infections,and gut health,are *** utilization of MCFAs and monoglycerides together with other feed additives such as organic acids and probiotics is also described,along with advances in molecular encapsulation and delivery ***,we discuss how MCFAs and monoglycerides demonstrate potential for feed pathogen mitigation to curb disease *** forward,we envision that MCFAs and monoglycerides may become an important class of feed additives in pig production for gut health improvement and feed pathogen mitigation.

关键词： Antibiotics Feed pathogen mitigation Growth promotion Gut health Immune enhancement MCFA Medium-chain fatty acids Monoglycerides

real-time flood forecast and flood alert map over the Huaihe river Basin in China using a coupled hydro-meteorological modeling system

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Science China(Technological Sciences) 2008年第7期51卷 1049-1063页

作者： LIN charles A. Department of Atmospheric and Oceanic Sciences and Global Environmental and Climate Change Centre McGill UniversityMontreal Canada H3A 2K6

A coupled hydro-meteorological modeling system is established for real-time flood forecast and flood alert over the Huaihe river Basin in China. The system consists of the mesoscale atmospheric model MC2 (Canadian Mesoscale Compressible Community) that is one-way coupled to the Chinese Xinanjiang distributed hydrological model, a grid-based flow routing model, and a module for acquiring real-time gauge precipitation. The system had been successfully tested in a hindcast mode using 1998 and 2003 flood cases in the basin, and has been running daily in a real-time mode for the summers of 2005 and 2006 over the Wangjiaba sub-basin of the Huaihe river Basin. The MC2 precipitation combined with gauge values is used to drive the Xinanjiang model for hydrograph prediction and production of flood alert map. The performance of the system is illustrated through an examination of real-time flood forecasts for the severe flood case of July 4―15, 2005 over the sub-basin, which was the first and largest flood event encountered to date. The 96-h forecasts of MC2 precipitation are first evaluated using observations from 41 rain gauges over the sub-basin. The forecast hydrograph is then validated with observations at the Wangjiaba outlet of the sub-basin. MC2 precipitation generally compares well with gauge values. The flood peak was predicted well in both timing and intensity in the 96-hour forecast using the combined gauge-MC2 precipitation. The real-time flood alert map can spatially display the propagation of forecast floods over the sub-basin. Our forecast hydrograph was used as opera-tional guidance by the Bureau of Hydrograph, Ministry of Water resources. Such guidance has been proven very useful for the Office of State Flood Control and Drought relief Headquarters in operational decision making for flood management. The encouraging results demonstrate the potential of using mesoscale atmospheric model precipitation for real-time flood forecast, which can result in a longer le

关键词： coupled hydro-meteorological modeling system flood forecast flood alert map MC2

Optimal product pricing and lot sizing decisions for multiple products with nonlinear demands

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Journal of Management Analytics 2016年第1期3卷 43-58页

作者： Naeem Bajwa Belleh Fontem charles r.Sox Department of Management College of BusinessUniversity of Arkansas at Little Rock2801 South University AvenueLittle RockArkansasUSA University of Mary Washington FredericksburgVirginiaUSA The University of Alabama TuscaloosaAlabamaUSA

Most manufacturing firms consider product pricing as a key strategic *** planning and scheduling,on the other hand,are mostly treated as a non-strategic *** businesses,therefore,follow some sequential decision-making process;where product prices are determined first and then operational plans are made to fulfill the resulting demand at the lowest possible *** this paper,we present a coordinated decision model approach for multiproduct pricing and lot sizing decisions for a manufacturer who has limited production *** the presented model is specific to demands that follow constant elasticity of the price,it can easily be extended to other convex demand *** show that a coordinated decision-making process where price and production plans are determined simultaneously may lead to substantially higher *** propose an efficient solution methodology for finding optimal prices and product quantities and use real-world data to demonstrate the applicability of this research.

关键词： pricing marketing and operations interface coordination non-linear programming

regeneration patterns of key pine species in a mixed-pine forest indicate a positive effect of variable retention harvesting and an increase in recruitment with time

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Forest Ecosystems 2020年第4期7卷 659-671页

作者： Priscilla A.Nyamai P.charles Goebel r.Gregory Corace III David M.Hix Natural resources Management Program Grand Valley State University1 Campus DrAllendaleMI 49401USA. Department of Forest Rangelandand Fire SciencesUniversity of Idaho875 Perimeter Drive MS 1133MoscowID 83844USA. Alpena-Montmorency Conservation District 1900 M-32 WAlpenaMI 49707USA. School of Environment and Natural resources The Ohio State University2021 Coffey RoadColumbusOH 43210USA.

Background:Many fire-dependent forests have experienced significant declines in species,structural,and functional *** changes are attributed in part to traditional management approaches that were dominated by even-aged regeneration methods such as *** retention harvesting(VrH)is an ecologically based forestry practice that involves retention of some mature overstory trees and other biological structures in the postharvest stand to emulate the effects of natural disturbance *** this study,we examined the effect of a VrH treatment on recruitment of historically dominant pine species and understory vegetation twoand six years after its implementation in a naturally regenerated mixed pine forest in the Upper Peninsula of Michigan,***:We found greater regeneration of red pine(Pinus resinosa L.)and eastern white pine(Pinus strobus L.)in VrH stands compared to the unharvested *** red pine recruitment was very low during the first 2 years,both species increased significantly from year two to year *** responses for the two species did not differ significantly between the aggregated and dispersed retention *** also found high recruitment of deciduous tree species,consisting primarily of sprouts,and red pine exhibited a negative correlation with these ***,time,and the interaction of treatment and time were significant factors in red pine *** had a strong effect on the understory vegetation,with significant decreases in shrubs and ferns over ***:The results suggest that VrH enhanced recruitment of red pine and eastern white pine and that this recruitment increased with *** identify competition from sprouts and unfavorable seedbed conditions as the main factors that limited recruitment of red pine during the first 2 *** reduce competing vegetation and improve seedbed conditions,we suggest following the VrH with a prescribed fire,mechanically removing s

关键词： Variable retention harvesting Aggregated retention Dispersed retention Mixed-pine forest Pinus resinosa Pinus strobus

Homological behavior of idempotent subalgebras and Ext algebras

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Science China Mathematics 2020年第2期63卷 309-320页

作者： Colin Ingalls charles Paquette School of Mathematics and Statistics Carleton UniversityOttawaON K1S 5E6Canada Department of Mathematics and Computer Science Royal Military College of CanadaKingstonON K7K 7B4Canada

Let A be a(left and right) Noetherian ring that is semiperfect. Let e be an idempotent of A and consider the ring Γ :=(1-e)A(1-e) and the semi-simple right A-module Se := e A/e rad A. In this paper, we investigate the relationship between the global dimensions of A and Γ, by using the homological properties of Se. More precisely, we consider the Yoneda ring Y(e) := Ext_A~*(Se, Se) of e. We prove that if Y(e) is Artinian of finite global dimension, then A has finite global dimension if and only if so does Γ. We also investigate the situation where both A and Γ have finite global dimension. When A is Koszul and finite dimensional, this implies that Y(e) has finite global dimension. We end the paper with a reduction technique to compute the Cartan determinant of Artin algebras. We prove that if Y(e) has finite global dimension, then the Cartan determinants of A and Γ coincide. This provides a new way to approach the long-standing Cartan determinant conjecture.

关键词： global dimension Noetherian ring semiperfect ring idempotent subalgebra Cartan determinant