6,669 research outputs found

    Climatic variables and performance of center pivot at Cristalina, Goiás, Brazil

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    Objetivou-se, com este trabalho, avaliar o desempenho de um pivô central em função da velocidade do vento (VV), umidade relativa do ar (UR) e temperatura média do ar (T) e estabelecer um modelo estatístico para estimativa da eficiência de aplicação da água em função dessas variáveis independentes. Dados foram coletados nos períodos da manhã e tarde, em três épocas do ano (12 e 13/08/05; 22 e 23/09/05 e 27 e 28/10/05), considerando-se duas velocidades de deslocamento do equipamento, 50 e 100%. O delineamento experimental foi o de blocos ao acaso para o fator velocidade do pivô com o fator época do ano em subparcelas e se considerando o período do dia como repetição. A pressão média no final da linha lateral foi de 137,3 kPa e próxima ao valor previsto pelo fabricante, ou seja, de 127,5 kPa. A lâmina média aplicada foi de 12 e de 5,7 mm para as velocidades de 50 e 100%, respectivamente. Os coeficientes de uniformidade de Christiansen (CUC) calculados resultaram em valores considerados, na literatura, aceitáveis. As lâminas médias coletadas no período da manhã foram maiores que as coletadas no período da tarde. As variáveis independentes VV, T e UR, influenciaram o valor da eficiência de aplicação. _________________________________________________________________________________________ ABSRACTThis research aimed to evaluate center pivot performance as a function of wind speed (VV), relative humidity of air (UR) and mean air temperature (T) and establish a stochastic model to estimate application efficiency as a function of these independent variables. Data were collected, during the morning and the afternoon period, and during three times of the year (August, 12 and 13; September, 22 and 23; and October, 27 and 28, 2005), considering two speeds of outer driver unit (50 and 100%). A randomized block design was used for factor speed of outer driver with factor time of the year as a split plot of factor speed, and considering period of the day as replication. The mean pressure head at the end of the lateral was 137.3 kPa and close to the value predicted by the dealer of 127.5 kPa. The average water depths applied were 12 and 5.7 mm for 50 and 100% speed, respectively. Calculated Christiansen's uniformity coefficient (CUC) provided values considered in literature as standard. Average water depths collected in the morning period were greater than the ones collected in the afternoon. VV, T and UR independent variables influenced significantly water application efficiency values

    Power-law bounds for increasing subsequences in Brownian separable permutons and homogeneous sets in Brownian cographons

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    The Brownian separable permutons are a one-parameter family -- indexed by p∈(0,1)p\in(0,1) -- of universal limits of random constrained permutations. We show that for each p∈(0,1)p\in (0,1), there are explicit constants 1/2<α∗(p)≤β∗(p)<11/2 < \alpha_*(p) \leq \beta^*(p) < 1 such that the length of the longest increasing subsequence in a random permutation of size nn sampled from the Brownian separable permuton is between nα∗(p)−o(1)n^{\alpha_*(p) - o(1)} and nβ∗(p)+o(1)n^{\beta^*(p) + o(1)} with probability tending to 1 as n→∞n\to\infty. In the symmetric case p=1/2p=1/2, we have α∗(p)≈0.812\alpha_*(p) \approx 0.812 and β∗(p)≈0.975\beta^*(p)\approx 0.975. We present numerical simulations which suggest that the lower bound α∗(p)\alpha_*(p) is close to optimal in the whole range p∈(0,1)p\in(0,1). Our results work equally well for the closely related Brownian cographons. In this setting, we show that for each p∈(0,1)p\in (0,1), the size of the largest clique (resp. independent set) in a random graph on nn vertices sampled from the Brownian cographon is between nα∗(p)−o(1)n^{\alpha_*(p) - o(1)} and nβ∗(p)+o(1)n^{\beta^*(p) + o(1)} (resp. nα∗(1−p)−o(1)n^{\alpha_*(1-p) - o(1)} and nβ∗(1−p)+o(1)n^{\beta^*(1-p) + o(1)}) with probability tending to 1 as n→∞n\to\infty. Our proofs are based on the analysis of a fragmentation process embedded in a Brownian excursion introduced by Bertoin (2002). We expect that our techniques can be extended to prove similar bounds for uniform separable permutations and uniform cographs.Comment: New version before journal submissio

    Dense Circulant Lattices From Nonlinear Systems

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    Circulant lattices are those with a circulant generator matrix. They can be described by a basis containing a vector and its circular shifts. In this paper, we present certain conditions under which the norm expression of an arbitrary vector of a circulant lattice is substantially simplified, and then investigate some of the lattices obtained under these conditions. We exhibit systems of nonlinear equations whose solutions yield lattices as dense as DnD_n in odd dimensions.Comment: preprint, 21 pages, 5 figure

    The scaling limit of the volume of loop O(n) quadrangulations

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    We study the volume of rigid loop-O(n)O(n) quadrangulations with a boundary of length 2p2p in the critical non-generic regime. We prove that, as the half-perimeter pp goes to infinity, the volume scales in distribution to an explicit random variable. This limiting random variable is described in terms of the multiplicative cascades of Chen, Curien and Maillard arXiv:1702.06916, or alternatively (in the dilute case) as the law of the area of a unit-boundary γ\gamma-quantum disc, as determined by Ang and Gwynne arXiv:1903.09120, for suitable γ\gamma. Our arguments go through a classification of the map into several regions, where we rule out the contribution of bad regions to be left with a tractable portion of the map. One key observable for this classification is a Markov chain which explores the nested loops around a size-biased vertex pick in the map, making explicit the spinal structure of the discrete multiplicative cascade.Comment: 45 pages, 6 figures, comments welcome

    The Case for Public Interventions during a Pandemic

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    Funding Information: This work has been supported by Marie Skłodowska Curie Actions ITN AffecTech (ERC H2020 Project 1059 ID: 722022). Publisher Copyright: © 2022 by the authors.Within the field of movement sensing and sound interaction research, multi-user systems have gradually gained interest as a means to facilitate an expressive non-verbal dialogue. When tied with studies grounded in psychology and choreographic theory, we consider the qualities of interaction that foster an elevated sense of social connectedness, non-contingent to occupying one’s personal space. Upon reflection of the newly adopted social distancing concept, we orchestrate a technological intervention, starting with interpersonal distance and sound at the core of interaction. Materialised as a set of sensory face-masks, a novel wearable system was developed and tested in the context of a live public performance from which we obtain the user’s individual perspectives and correlate this with patterns identified in the recorded data. We identify and discuss traits of the user’s behaviour that were accredited to the system’s influence and construct four fundamental design considerations for physically distanced sound interaction. The study concludes with essential technical reflections, accompanied by an adaptation for a pervasive sensory intervention that is finally deployed in an open public space.publishersversionpublishe

    Aplicação do biopolímero de celulose como biossorvente alternativo na remoção do diclofenaco de sódio/ Application of cellulosis biopolymer as an alternative biosorbent in sodium diclophenac removal

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    A presença de medicamentos em corpos d'água recebeu atenção pela remoção incompleta através de processos convencionais de tratamento de águas residuais. Portanto, o presente trabalho tem como objetivo avaliar a capacidade de remoção de poluentes orgânicos (diclofenaco de sódio) utilizando o biopolímero de celulose in natura (CN) e celulose funcionalizada (CF) são determinados através dos parâmetros cinéticos dos modelos de isotermas de Langmuir e Freudlich. Além disso, a celulose foi quimicamente modificada com FeCl3 e foi caracterizada por porosimetria de N2, difração de raios X (DRX), espectroscopia no infravermelho por transformada de Fourier (FT-IR) e potencial zeta (PZ), a fim de avaliar suas propriedades estruturais os testes de adsorção foram realizados em reator batelada com uma concentração do fármaco (60 mg L-1) com 0,7 g L-1 do biossorvente, avaliando os parâmetros cinéticos.Os biossorventes apresentam características de materiais mesoporosos, com área específica considerável (205,9 m² g-1 e 304,2 m² g-1 para CN e CF, respectivamente), carga superficial negativa, presença de fases amorfa e cristalina e grupos funcionais característicos de celulose e hemicelulose. Os resultados mostraram que materiais alternativos de celulose podem ser utilizados como adsorventes no tratamento de efluentes do fármaco diclofenaco de sódio

    File Specification for the 7-km GEOS-5 Nature Run, Ganymed Release Non-Hydrostatic 7-km Global Mesoscale Simulation

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    This document describes the gridded output files produced by a two-year global, non-hydrostatic mesoscale simulation for the period 2005-2006 produced with the non-hydrostatic version of GEOS-5 Atmospheric Global Climate Model (AGCM). In addition to standard meteorological parameters (wind, temperature, moisture, surface pressure), this simulation includes 15 aerosol tracers (dust, sea-salt, sulfate, black and organic carbon), O3, CO and CO2. This model simulation is driven by prescribed sea-surface temperature and sea-ice, daily volcanic and biomass burning emissions, as well as high-resolution inventories of anthropogenic sources. A description of the GEOS-5 model configuration used for this simulation can be found in Putman et al. (2014). The simulation is performed at a horizontal resolution of 7 km using a cubed-sphere horizontal grid with 72 vertical levels, extending up to to 0.01 hPa (approximately 80 km). For user convenience, all data products are generated on two logically rectangular longitude-latitude grids: a full-resolution 0.0625 deg grid that approximately matches the native cubed-sphere resolution, and another 0.5 deg reduced-resolution grid. The majority of the full-resolution data products are instantaneous with some fields being time-averaged. The reduced-resolution datasets are mostly time-averaged, with some fields being instantaneous. Hourly data intervals are used for the reduced-resolution datasets, while 30-minute intervals are used for the full-resolution products. All full-resolution output is on the model's native 72-layer hybrid sigma-pressure vertical grid, while the reduced-resolution output is given on native vertical levels and on 48 pressure surfaces extending up to 0.02 hPa. Section 4 presents additional details on horizontal and vertical grids. Information of the model surface representation can be found in Appendix B. The GEOS-5 product is organized into file collections that are described in detail in Appendix C. Additional details about variables listed in this file specification can be found in a separate document, the GEOS-5 File Specification Variable Definition Glossary. Documentation about the current access methods for products described in this document can be found on the GEOS-5 Nature Run portal: http://gmao.gsfc.nasa.gov/projects/G5NR. Information on the scientific quality of this simulation will appear in a forthcoming NASA Technical Report Series on Global Modeling and Data Assimilation to be available from http://gmao.gsfc.nasa.gov/pubs/tm/
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