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

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

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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

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Physical habitat condition as a key tool to maintain freshwater biodiversity in neotropical artificial ponds

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Water Biology and Security 2023年第3期2卷 30-35页

作者： Marden S.Linares Livia B.dos santos Marcos callisto Jean c.santos Universidade Federal de Minas Gerais Instituto de Ciencias BiologicasDepartamento de GeneticaEcologia e EvoluçaoLaboratorio de Ecologia de BentosAv.Antonio Carlos 6627CEP 31270-901PampulhaBelo HorizonteMGBrazil Laboratorio de Macroecologia e conservaçao da Biodiversidade Departamento de Botanica e EcologiaUniversidade Federal do Mato GrossoAv.Fernando Correa da Costa2367Boa EsperançaCuiabaMato GrossoCEP 78060-900Brazil Programa de Pos-Graduaçao em ciencias Ambientais Instituto de Ciencias NaturaisHumanas e SociaisUniversidade Federal do Mato GrossoAvenida Alexandre Ferronato1200SinopMTCEP 78550-728Brazil Universidade Federal de Sergipe Departamento de EcologiaCampus Sao Cristovao-Cidade Universitaria Prof.Jose Aloísio de CamposCEP 49100-000Sao CristovaoSergipeBrazil

In areas highly affected by anthropogenic disturbances,artificial(human-made)freshwater ecosystems can provide habitat for maintaining and conserving regional freshwater *** assessed how the physical habitat of artificial ponds affected the structure of benthic macroinvertebrate *** do so,we tested two hypotheses.(1)Physical habitat disturbances are not detrimental to the diversity of nearby artificial ponds,and(2)Physical habitat disturbances do not cause significant shifts in taxonomic *** results rejected both null hypotheses,i.e.,macroinvertebrate diversity metrics correlated significantly and positively with Physical Habitat Integrity index scores,and only sites with high habitat condition scores were significantly associated with sensitive indicator *** results highlight the importance of maintaining physical habitat conditions for sustaining the ecological health of artificial ponds.

关键词： Bioindicators Ecosystem management Lentic ecosystems

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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

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Introducing System Identification Strategy into Model Predictive control

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Journal of Systems Science & complexity 2020年第5期33卷 1402-1421页

作者： WANG Jianhong ricardo A.Ramirez-Mendoza JORGE de J Lozoya santos School of Electronic Engineering and Automation Jiangri University of Science and TechnologyGanzhou343000China School of Engineering and Sciences Tecnologico de MonterreyMonterreyAve.Eugenio Garza Sada 2501MonterreyN.L.64849Merico

As system identification theory and model predictive control are belonged to two different research fields separately,so one gap exists between these two *** alleviate this gap between them,one new idea proposed in this paper is to introduce system identification theory into model predictive *** the most important element in model predictive control is the prediction of the output value for a nonlinear system,then the problem of deriving the prediction of the output value can be achieved by system identification *** specifically,a Bayesian approach is applied for the nonparametric estimation by modeling the prediction as realizations of zero mean random *** comparing this kind of prediction corresponding to this Bayesian approach and the former direct weight optimization identification for nonlinear system,the authors see that if the unknown weights are chosen appropriately,these two approaches are equivalent to each *** on the obtained prediction of the output value,the authors substitute this prediction of the output value into one cost function of model predictive control,and then a quadratic programming problem with inequality constraints is *** to solve this quadratic programming problem,a detailed process about how to derive its dual form is *** the dual problem has a simple constraint set,it is amenable to the use of the common Gauss-Seidel algorithm,whose convergence can be shown ***,one simulation example confirms the proposed theoretical results.

关键词： Equivalence model predictive control nonparametric estimation system identification

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Intelligent fault detection and location scheme for modular multi‐level converter multi‐terminal high‐voltage direct current

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High Voltage 2021年第1期6卷 125-137页

作者： Qingqing Yang Jianwei Li ricardo santos Kaijia Huang Petar Igic coventry University CoventryUK Department of Engineering Science University of OxfordOxfordUK centre of Engineering Federal University of ABCSanto AndreBrazil DTU Energy Technical University of DenmarkKongens LyngbyDenmark

In order to overcome the drawbacks of the conventional protection methods in high‐voltage direct current transmission lines, a deep learning approach is proposed that directly learn the fault conditions based on unsupervised feature extraction to the detection and location decision by leveraging the hidden layer activations of recurrent neural network. The deep‐recurrent neural network boosting with the gated recurrent unit compared with the long short‐term memory unit is used by analysing both the signal presented in time domain and frequency domain. The proposed method is tested based on a modular multilevel converter based four‐terminal high‐voltage direct current system. Various faults under different conditions were simulated against fault resistance, external faults and small disturbance immunity with the validity, and the simulation verified a high accuracy, robustness and fast results because of the utilization of characteristic feature extraction.

关键词： fault overcome high

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Urgent tracheostomy： four-year experience in a tertiary hospital

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World Journal of Emergency Medicine 2016年第3期7卷 227-230页

作者： Liliana costa ricardo Matos Sara Julio Fernando Vales Margarida santos Otorhinolaryngology Sao Joao Hospital Center Porto 4200-319 Portugal

BAcKGROUND: Urgent airway management is one of the most important responsibilities of otolaryngologists, often requiring a multidisciplinary approach. Urgent surgical airway intervention is indicated when an acute airway obstruction occurs or there are intubation difficulties. In these situations, surgical tracheostomy becomes extremely ***: We retrospectively studied the patients who underwent surgical tracheostomy from 2011 to 2014 by an otolaryngologist team at the operating theater of the emergency department of a tertiary hospital. Indications, complications and clinical evolution of the patients were ***: The study included 56 patients(44 men and 12 women) with a median age of 55 years. The procedure was performed under local anesthesia in 21.4% of the patients. Two(3.6%) patients were subjected to conversion from cricothyrostomy to tracheostomy. Head and neck neoplasm was indicated in 44.6% of the patients, deep neck infection in 19.6%, and bilateral vocal fold paralysis in 10.7%. Stridor was the most frequent signal(51.8%). Of the 56 patients, 15 were transferred to another hospital. Among the other 41 patients, 21 were decannulated(average time: 4 months), and none of them were cancer patients. complications occurred in 5(12.2%) patients: hemorrhage in 3, surgical wound infection in 1, and cervico-thoracic subcutaneous emphysema in 1. No death was related to the ***: Urgent tracheostomy is a life-saving procedure for patients with acute airway obstruction or with diffi cult intubation. It is a safe and effective procedure, with a low complication rate, and should be performed before the patient's clinical status turns into a surgical emergency situation.

关键词： Tracheostomy cricothryrostomy Stridor Airway obstruction

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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

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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

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Evolution of the Socio-cognitive Structure of Knowledge Management(1986–2015): An Author co-citation Analysis

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Journal of Data and Information Science 2019年第2期4卷 36-55页

作者： carlos Luis González-Valiente Magda León santos ricardo Arencibia-Jorge Biblioteca Nacional de cuba "José Martí" ave.Independencia Facultad de comunicación Universidad de la Habana San Pedro entre Ermita y Avenida Independencia Empresa de Tecnologías de la Información

Purpose: The evolution of the socio-cognitive structure of the field of knowledge management(KM) during the period 1986–2015 is described. Design/methodology/approach: Records retrieved from Web of Science were submitted to author co-citation analysis(AcA) following a longitudinal perspective as of the following time slices: 1986–1996, 1997–2006, and 2007–2015. The top 10% of most cited first authors by sub-periods were mapped in bibliometric networks in order to interpret the communities formed and their ***: KM is a homogeneous field as indicated by networks results. Nine classical authors are identified since they are highly co-cited in each sub-period, highlighting Ikujiro Nonaka as the most influential authors in the field. The most significant communities in KM are devoted to strategic management, KM foundations, organisational learning and behaviour, and organisational theories. Major trends in the evolution of the intellectual structure of KM evidence a technological influence in 1986–1996, a strategic influence in 1997–2006, and finally a sociological influence in 2007–*** limitations: Describing a field from a single database can offer biases in terms of output coverage. Likewise, the conference proceedings and books were not used and the analysis was only based on first authors. However, the results obtained can be very useful to understand the evolution of KM *** implications: These results might be useful for managers and academicians to understand the evolution of KM field and to(re)define research activities and organisational ***/value: The novelty of this paper lies in considering AcA as a bibliometric technique to study KM research. In addition, our investigation has a wider time coverage than earlier articles.

关键词： Knowledge management Bibliometrics Author co-citation analysis Knowledge domain visualization Social network analysis Intellectual structure

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