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Modeling neutral-atmospheric electromagnetic delays in a“big data”world

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Geo-Spatial Information Science 2018年第2期21卷 75-79页

作者： Marcelo c.santos Thalia Nikolaidou Department of Geodesy and Geomatics Engineering University of New BrunswickFrederictonCanada

If left unmodeled,the delay suffered by electromagnetic waves while crossing the neutral atmosphere negatively affects Global Navigation Satellite System *** modeling of the delay has been carried out by means of empirical models formulated based on climatological information or using information extracted from numerical weather prediction(NWP)*** paper explores the potential use of meteorological information of several types that will become available with the increasing number of sensors(e.g.a cell phone,or the thermometer of a nearby smart home)in *** can we make use of these potentially huge datasets,which may help to provide the best possible representation of the neutral atmosphere at any given time,as readily and as accurately as possible?This situation falls in the realm of Big Data.A few potential scenarios,a sequential improvement of Marini mapping function coefficients,a self-feeding NWP,and near real-time empirical model updates,are discussed in this *** pros and cons of each approach are discussed in comparison with what is done *** indicate that they have potential for a positive contribution.

关键词： Global navigation satellite system(GNSS) big data neutral atmosphere

Effect of age and different doses of dietary vitamin E on breast meat qualitative characteristics of finishing broilers

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Animal Nutrition 2021年第1期7卷 163-167页

作者： Vivian Vieira Francielle O.Marx Lucas S.Bassi Marley c.santos Alexandre Oba Simone Gisele de Oliveira Alex Maiorka Federal University of Paraná Curitiba80035-050Brazil State University of Londrina Londrina86055-900Brazil

The supplementation of vitamin E on broiler chicken diets is essential to the prevention of lipid oxidation reactions in the meat and improvement of meat *** objective of this study was to assess the effect of different doses of dietary vitamin E on breast meat quality of broiler chickens in the finishing *** doses of vitamin E were used(30,90,150,210,and 270 mg/kg feed)in broilers'diets from 42 to 54 d of age.A completely randomized design was conducted,followed by a split-plot,where the vitamin E dose was considered as the whole plot,and broilers'age at slaughter was the *** meat quality was assessed at 4 different ages(45,48,51,and 54 d old),using 50 birds per age,totaling 200 *** quality characteristics evaluated were:pH at 24 h post mortem,color(brightness,redness,and yellowness),water holding capacity,cooking loss,shear force,and lipid *** was no interaction between age and dose of vitamin E for meat quality characteristics(P>0.05).The age at slaughter had a quadratic effect(Pce value was higher in breast meat of birds slaughtered at later ages(Pct was *** increased linearly(Pcooking loss,and lipid *** this study,increasing vitamin E doses in the finishing period increased the brightness of broiler breast meat,whereas slaughtering at later ages resulted in greater meat pH and shear force value.

关键词： Alpha-tocopherol Broiler chicken Meat quality Oxidation Vitamin

Optimizing the use of open chambers to measure ammonia volatilization in field plots amended with urea

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Pedosphere 2021年第2期31卷 243-254页

作者： Márcio R.MARTINS Leonardo F.SARKIS Selenobaldo A.c.SANT’ANNA camila A.santos Karla E.ARAUJO Ricardo c.santos Ednaldo S.ARAÚJO Bruno J.R.ALVES claudia P.JANTALIA Robert M.BODDEY Mohammad ZAMAN Segundo URQUIAGA Embrapa Agrobiology Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Federal Rural University of Rio de Janeiro(UFRRJ) Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Agroscope Research Division Agroecology and EnvironmentClimate and Agriculture GroupReckenholzstrasse 191Zurich 8046(Switzerland) Soil and Water Management&crop Nutrition Joint FAO/IAEA Division of Nuclear Techniques in Food&AgricultureP.O.Box 100Vienna A-1400(Austria)

Measuring ammonia(NH_(3))volatilization from urea-fertilized soils is crucial for evaluation of practices that reduce gaseous nitrogen(N)losses in *** small area of chambers used for NH_(3)volatilization measurements compared with the size of field plots may cause significant errors if inadequate sampling strategies are *** aims were:i)to investigate the effect of using multiple open chambers on the variability in the measurement of NH_(3)volatilization in urea-amended field plots and ii)to define the critical period of NH_(3)-N losses during which the concentration of sampling effort is capable of reducing *** use of only one chamber covering 0.015%of the plot(51.84 m^(2))generates a value of NH_(3)-N loss within an expected margin of error of 30%around the true *** reduce the error margin by half(15%),3–7 chambers were required with a mean of 5 chambers per *** the sampling efforts in the first two weeks after urea application,which is usually the most critical period of N losses and associated errors,represents an efficient strategy to lessen uncertainty in the measurements of NH_(3)*** strategy enhances the power of detection of NH_(3)-N loss abatement in field experiments using chambers.

关键词： chamber method experimental error gas emission low-cost chamber nitrogen cycling nitrogen loss soil variability

capacitorless Solid-state Power Filter for Single-phase Dc-Ac converters

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cES Transactions on Electrical Machines and Systems 2024年第3期8卷 367-377页

作者： Haitham Kanakri Euzeli c.Dos santos Purdue University Electrical and Computer Engineering DepartmentIndianapolisIN46202 USA

converters rely on passive filtering as a crucial element due to the high-frequency operational characteristics of power *** filtering methods involve a dual inductor-capacitor(Lc)cell or an inductor-capacitor-inductor(LcL)***,capacitors are susceptible to wear-out mechanisms and failure ***,the necessity for monitoring and regular replacement adds to an elevated cost of ownership for such *** utilization of an active output power filter can be used to diminish the dimensions of the Lc filter and the electrolytic dc-link capacitor,even though the inclusion of capacitors remains an indispensable part of the *** paper introduces capacitorless solid-state power filter(SSPF)for single-phase dc-ac *** proposed configuration is capable of generating a sinusoidal ac voltage without relying on *** proposed filter,composed of a planar transformer and an H-bridge converter operating at high frequency,injects voltage harmonics to attain a sinusoidal output *** design parameters of the planar transformer are incorporated,and the impact of magnetizing and leakage inductances on the operation of the SSPF is *** analysis,supported by simulation and experimental results,are provided for a design example for a single-phase *** total harmonic distortion observed in the output voltage is well below the IEEE 519 *** system operation is experimentally tested under both steady-state and dynamic conditions.A comparison with existing technology is presented,demonstrating that the proposed topology reduces the passive components used for filtering.

关键词： Solid-state power filter(SSPF) capacitorless topology Active output power filter(AOF) Planar transformer Electrolytic capacitor Lifetime Wear-out mechanisms

comment on “constraining the smoothness parameter and dark energy using observational H(z) data”

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Research in Astronomy and Astrophysics 2011年第6期11卷 637-640页

作者： V.c.Busti R.c.santos Instituto de Astronomia Geofísica e Ciências AtmosféricasUniversidade de So PauloSo Paulo05508-090 SPBrazil Departamento de ciê ncias Exatas e da Terra Universidade Federal de So Paulo(UNIFESP)Diadema09972-270 SPBrazil

We discuss a recent analysis by Yu et al.[RAA 11,125（2011）] about constraints on the smoothness parameter α and dark energy models using observational H（z） *** is argued here that their procedure is conceptually inconsistent with the basic assumptions underlying the adopted Dyer-Roeder *** order to properly quantify the influence of the H（z） data on the smoothness parameter α,a χ2-test involving a sample of type Ia supernovae and H（z） data in the context of a flat ΛcDM model is *** result is confronted with an earlier approach discussed by santos et al.（2008） without H（z） *** the（Ωm,α） plane,it is found that such parameters are now restricted to be in the intervals 0.66 ≤ α ≤ 1.0 and 0.27 ≤ Ωm ≤ 0.37 within the 95.4 confidence level（2σ）,and,therefore,are fully compatible with the homogeneous *** basic conclusion is that a joint analysis involving H（z） data can indirectly improve our knowledge about the influence of the ***,this happens only because the H（z） data provide tighter constraints on the matter density parameter Ωm.

关键词： cosmology — dark energy — cosmological parameters

Unveiling an important interaction in forestry:Ectomyelois muriscis and Khaya grandifoliola cankers and tree growth

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Journal of Forestry Research 2021年第3期32卷 1287-1293页

作者： Lísias coelho AndréRTerra Nascimento jean carlos santos Vinícius Flabes Silva Instituto de ciências Agrárias Universidade Federal de UberlandiaUberlandiaBrazil Instituto de Biologia Universidade Federal de UberlandiaUberlandiaBrazil Departamento de Ecologia Universidade Federal de SergipeSergipeBrazil

African mahogany,Khaya grandifoliola ***.,is the most planted mahogany species in Brazil,and became the choice species when plantations of Brazilian mahogany,Swietenia macrophyla King became unsustainable due to their susceptibility to the shoot borer Hypsipyla grandella *** study evaluated plantation growth and the occurrence of cankers associated with Ectomyelois muriscis Dyar *** recorded plantation volume,survival,and canker incidence of a plantation established in 2010 at 6 m×5.5 m *** were collected and reared on canker bark fragments until final adult *** were frequently associated with Ectomyelois muriscis *** average incidence of the moth(2.9%)was not a significant concern,however,an extreme incidence of 45%would indicate that management strategies should be *** is the first report of Ectomyelois muriscis attacking the bark of Khaya grandifoliola in the cerrado biome.

关键词： African mahogany Stem cankers Potential pest Stand growth

The road to sustainable use and waste management of plastics in Portugal

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Frontiers of Environmental Science & Engineering 2022年第1期16卷 91-106页

作者： Joana c.Prata Ana LPatrício Silva Armando cDuarte Teresa Rocha-santos centre for Environmental and Marine Studies(cESAM)&Department of chemistry University of Aveiro3810-193 AveiroPortugal centre for Environmental and Marine Studies(cESAM)&Department of Biology University of Aveiro3810-193 AveiroPortugal

As a European Union(EU)member,Portugal must comply with reductions in plastic *** Portugal,the 330 items/100 m of beach litter,comprising up to 3.9 million pieces and of which 88%is plastic,is higher than the EU median(149 items/100 m)and must be reduced to 20 items/100 m(94%).Integrative measures are needed to reduce littering and improve plastics’use and disposal under the circular *** this 414 kt of plastic packaging waste,163 kt were declared plastic packaging,140 kt subjected to recycling,and 94 kt to energy *** current recycling rate of plastic packaging(34%)should be improved to reach EU recycling averages(42%)and goals and to provide widespread benefits,considering revenues of 167€/*** a net importer of waste,Portugal could benefit from the valorization of imported *** increased recycling,pyrolysis and gasification could provide short-term alternatives for producing value-added substances from plastic waste,such as hydrogen,consistent with the National Plan of Hydrogen and improving ongoing regulations on single-use *** manuscript provides an integrative view of plastics in Portugal,from use to disposal,providing specific recommendations under the circular economy.

关键词： Single-use plastics Plastic packaging Plastic waste Waste management Waste shipment Lightweight plastic bags

TODIM and TOPSIS with Z-numbers

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 283-291页

作者： Renato A.KROHLING André G.c.PAcHEcO Guilherme A.dos santos Department of Production Engineering Federal University of Espirito Santo Graduate Program in computer Science Federal University of Espirito Santo

In this paper, we present an approach that can handle Z-numbers in the context of multi-criteria decision-making problems. The concept of Z-number as an ordered pair Z=(A, B) of fuzzy numbers A and B is used, where A is a linguistic value of a variable of interest and B is a linguistic value of the probability measure of A. As human beings, we communicate with each other by means of natural language using sentences like "the journey from home to university most likely takes about half an hour." The Z-numbers are converted to fuzzy numbers. Then the Z-TODIM and Z-TOPSIS are presented as a direct extension of the fuzzy TODIM and fuzzy TOPSIS, respectively. The proposed methods are applied to two case studies and compared with the standard approach using crisp values. The results obtained show the feasibility of the approach.

关键词： Multi-criteria decision-making TODIM TOPSIS Fuzzy number Z-number

can small-scale altitudinal gradients predict spatial and temporal patterns in tropical forests?

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Journal of Forestry Research 2021年第5期32卷 1854-1865页

作者： Mariana caroline Moreira Morelli cléber Rodrigo de Souza jean Daniel Morel Vinícius Andrade Maia Alisson Borges Miranda santos Kaline Fernandes Miranda Rubens Manoel dos santos Forest Sciences Department Federal University of LavrasCampus UniversitárioCx.P.3037LavrasMGCEP 37200-000Brazil Department of Biology Federal University of LavrasCampus UniversitárioLavrasMGCEP 37200-000Brazil

In tropical montane forests,compositional and structural changes are commonly driven by broad-scale altitudinal ***,given the lack of knowledge on small-scale vegetation changes and temporal dynamics,we address the effects of small-scale variations in soil and altitude on tree community structure,temporal dynamics and phylogenetic diversity in a semi-deciduous tropical forest of the Atlantic Forest Domain,southeastern *** 2010 and 2015 we sampled thirty plots of 400 m^(2),set up along an altitudinal gradient between 1000 and 1500 m a.s.I..In each plot,we collected soil samples for chemical and textural *** fitted linear models to test the effects of altitude and soil on community dynamics and phylogenetic *** and soil explained the spatial variation in number of individuals and phylogenetic diversity *** lower to higher altitudes,we found decreasing fertility,increasing tree density and decreasing phylogenetic *** significantly influenced the increases in total biomass(from 240.9 to 255.4 t ha^(-1))and individual biomass(from 0.15 to 0.17 t)recorded in the *** while community temporal dynamics had rates of 1.96%for mortality,1.02%for recruitment,1.61%for biomass loss and 2.81%for biomass gain,none of them were explained by altitude or *** species substitution averaged0.1 in the ***,these results suggest that the small-scale variations in altitude and soil likely determine the conditions and resources that drive community assembly and structure,which are expressed by spatial variations along the altitudinal *** the same time,temporal patterns were not influenced by altitude-related environmental variation,resulting in a similar dynamic behaviour across the gradient,suggesting that broad-scale factors may play a more important role than local ones.

关键词： Fine-scale Semideciduous forests Montane forests Dynamic patterns