Consulta: subjectFacets:"Drift"
Registros recuperados: 10
Data/hora: 06/06/2024 07:53:19

Enhanced Arctic Sea Ice Drift Estimation Merging Radiometer and Scatterometer Data
Provedor de dados: 5
Autores: Ardhuin, Fanny; Ezraty, Robert.
Satellites enable daily and global coverage of the polar oceans and provide a unique monitoring capability of sea ice dynamics. Sea ice drift maps can be estimated in Arctic from several satellite sensors, particularly from scatterometers and radiometers. This study presents the benefits of combining single drift fields at the same resolution into a "merged" field, built at three-and six-day lags during winters with a 62.5-km resolution. It is shown that combining these drift fields not only increases the reliability of the displacement estimation and the number of estimated vectors to almost a full ice covered area but also expands the time period over which these estimations are reliable from freeze until the melt onset. The autumn-winter-spring sea ice...
Tipo: Text
Palavras-chave: Arctic; Advanced Scatterometer (ASCAT); Drift; Merging; Scatterometry; Sea ice.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00088/19895/17729.pdf

Validation of Arctic sea ice drift with IABP buoys
Provedor de dados: 5
Autores: Ardhuin, Fanny; Ezraty, Robert.
Satellites enable daily and global coverage of the polar oceans, providing an unique monitoring capability of sea ice dynamics over Arctic and Antarctic. Available geophysical parameters include ice concentration, extent, type and sea ice drift. Backscatter map from SeaWinds/QuikSCAT and brightness temperature maps from Special Sensor Microwave Imager (SSM/I) are available at a pixel resolution of 12,5 km from which ice drift can be estimated for each sensor. Since 1999, IFREMER makes available a "Merged" sea ice drift data set based on the combination of these drifts at 3 and 6-day lags at the grid resolution of 62,5 km. It has been demonstrated that combining these drifts increases the number of valid vectors.  In this paper, the validation of this...
Tipo: Text
Palavras-chave: Arctic; Buoys; Drift; Sea ice; AMSR E; Radiometer; Scatterometer; Arctique; Bouées; Dérive; Glaces de mer; AMSR E; Radiomètre; Diffusiomètre.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/acte-1292.pdf

Inusual arribazón de Sargassum fluitans (Børgesen) Børgesen en la costa  centro-sur de Cuba
Provedor de dados: 20
Autores: Moreira, A.; Alfonso, A.
Sargassum fluitans y Sargassum natans son macroalgas pardas holopelágicas que se pueden agregar para formar extensas  masas flotantes en la superficie del Atlántico Norte (Mar de los Sargazos). El presente trabajo describe la ocurrencia de una  excesiva arribazón de Sargassum fluitans en la costa este de la provincia de Cienfuegos, región centro-sur de Cuba, en mayo  de 2012. El mayor impacto de la arribazón por efecto mecánico sobre la costa fue reportado en el sector turístico. Se  observaron condiciones meteorológicas atípicas durante la arribazón de Sargassum.
Tipo: Journal Contribution
Palavras-chave: Drift; Algae resources.
Ano: 2013
URL: http://hdl.handle.net/1834/5248

Beyond selection
Provedor de dados: 97
Autores: VARGAS,ALEXANDER O.
It has been argued that the study of natural selection and quantitative genetics should have a central role in evolutionary thinking and undergraduate teaching in Chile. Extensive operational use of the concept of natural selection may seem consistent with this argument. However, advances of evolutionary knowledge in independent fields such as phylogenetic analysis, developmental evolution, and paleontology cannot be ignored. I argue here that the role of natural selection in contemporary evolutionary biology can be compared to that of Newtonian mechanics in contemporary physics: it can describe a given domain of observations, but it is insufficient to handle the different sources of evolutionary knowledge. Overemphasis on natural selection as the...
Tipo: Journal article
Palavras-chave: Evolution; History; Development; Epigenesis; Drift.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000400012

Photosynthetic activity of coffee after application of glyphosate subdoses - doi: 10.4025/actasciagron.v35i1.15440
Provedor de dados: 1
Autores: Carvalho, Felipe Paolinelli de; Universidade Federal de Viçosa; França, André Cabral; Universidade Federal dos Vales do Jequitinhonha e Mucuri; Lemos, Vinícius Teixeira; Universidade Federal de Lavras; Ferreira, Evander Alves; Universidade Federal dos Vales do Jequitinhonha e Mucuri; Santos, José Barbosa dos; Universidade Federal dos Vales do Jequitinhonha e Mucuri; Silva, Antonio Alberto da; Universidade Federal de Viçosa.
Farmers use non-selective herbicides, such as glyphosate, in directed applications to control weeds in coffee crops. Despite the precautions used during the application of herbicides, there are usually reports of poisoning in plantation areas. Moreover, it is fundamental to understand the effects of glyphosate on photosynthetic processes. The present study aimed to evaluate the characteristics associated with the photosynthetic activity in coffee cultivars subjected to doses of glyphosate. The experiment was conducted in a greenhouse using three varieties of coffee (Coffea arabica), including Acaiá (MG-6851), Catucaí Amarelo (2 SL) and Topázio (MG-1190), and three subdoses of glyphosate (0.0, 115.2 and 460.8 g ha-1) in a 3 x 3 factorial scheme. Herbicide...
Tipo: Pesquisa empírica
Palavras-chave: 5.01.03.00-8 herbicide; EPSPs; Coffea arabica; Photosynthetic rate; Drift Fitotecnia herbicide; EPSPs; Coffea arabica; Photosynthetic rate; Drift.
Ano: 2012
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/15440

Precision spray modeling using image processing and artificial neural network
Provedor de dados: 111
Autores: Azizpanah, Amir; Rajabipour, Ali; Alimardani, Reza; Kheiralipour, Kamran; Mohammadi, Vahid.
This study employed artificial neural network method for predicting the sprayer drift under different conditions using image processing technique. A wind tunnel was used for providing air flow in different velocities. Water Sensitive Paper (WSP) was used to absorb spray droplets and an automatic algorithm processed the images of WSPs for measuring droplet properties including volume median diameter (Dv0.5) and Surface Coverage Percent (SCP). Four Levenberg-Marqurdt models were developed to correlate the sprayer drift (output parameter) to the input parameters (height, pressure, wind velocity and Dv0.5). The ANN models were capable of predicting the output variables in different conditions of spraying with a high performance. Both models predicted the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sprayer; Drift; Image processing; Artificial Neural Network.
Ano: 2015
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3261

Design, construction and evaluation of a sprayer drift measurement system
Provedor de dados: 111
Autores: Azizpanah, Amir; Rajabipour, Ali; Alimardani, Reza; Kheiralipour, Kamran; Ghamari, Bahram; Mohammadi, Vahid.
Spray drift study for reducing environmental hazards and protecting crops is of high importance as the pesticides used today are more active and many are non-selective. Drift potential can be restricted by assessing and optimizing equipment design, application parameters, the liquid spray properties, type of formulation and environmental conditions. The aim of this research was to design, construct and assess an intelligent system to determine the level of the spraying drift. The main parts of the system were liquid supply mechanism, pipes and nozzles, a controlled pneumatic system to pressurize the liquid, a nozzle moving system with a controlling panel and a tunnel for wind providing and control. To assess the performance of sprayer and drift of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sprayer; Wind tunnel; Drift; Volumetric mean diameter.
Ano: 2015
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3308

Drift of ichthyoplankton in two channels of the Paraná River, between Paraná and Mato Grosso do Sul states, Brazil
Provedor de dados: 52
Autores: Bialetzki,Andréa; Sanches,Paulo Vanderlei; Cavicchioli,Maristela; Baumgartner,Gilmar; Ribeiro,Ricardo Pereira; Nakatani,Keshiyu.
Analysis of drift of ichthyoplankton in two channels in the River Paraná, Brazil, were made. Sampling was undertaken from October 1995 to April 1996 during nychthemeral cycles. Water samples were collected to determine several environmental variables. Eggs densities largely differed to layers, times of day and months. In both the channels, highest occurrence of eggs was detected between January and March; greater concentrations at the bottom, during night. With regard to larvae, densities were significantly different in channels, times of days and months. Maximum occurrences were seen in the right channel, in both layers, with largest capture between January and March. Surface of the both channels presented highest density of larvae during night. Water...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Drift; Ichthyoplankton; Paraná River.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89131999000100008

Evaluation of Low-Drift Nozzles in Agrochemical Applications in Orchards
Provedor de dados: 117
Autores: Behmer,Sergio; Di Prinzio,Alcides; Striebeck,Guillermina; Magdalena,Jorge.
Fruit production demands several phytosanitary treatments per year. The efficiency of these treatments is affected by product loss because of drift, a situation that is aggravated by frequent high winds and the presence of a substantial rural population. The objective of this study was to evaluate the distribution and to quantify product losses in fruit orchard applications. Fluorescent tracers with air-blast sprayers were applied, using air-induction hollow cone nozzles, compared to conventional hollow cone nozzles. To evaluate drift, pipes cleaner were placed on columns behind the adjacent row to the treated one, and for the losses under the tree, Petri dishes were located below the treated row; for the distribution in the tree, leaves were collected...
Tipo: Journal article
Palavras-chave: Orchards; Sprayers; Drift; Air-induction nozzles.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300017

Effect of Pressure on the Quality of Pesticide Application in Orchards
Provedor de dados: 117
Autores: Di Prinzio,Alcides; Behmer,Sergio; Magdalena,Jorge; Chersicla,Germán.
Only part of the active ingredient used in agrochemical applications in orchards is retained on the trees. The product that is not retained is lost as sedimentation in the soil and as drift, the latter being a major source of environmental pollution. Unfavorable atmospheric conditions affect the uniformity of distribution and increase product loss. This can be mitigated by the utilization of larger drops. The objective of the present work was to evaluate the effect of service pressure on distribution in the trees and product loss by using a conventional hydro pneumatic sprayer. A fluorescent tracer was applied on fruit trees by an airblast sprayer, with two treatments: high pressure (1800 kPa) and low pressure (500 kPa). Samples were collected from the...
Tipo: Journal article
Palavras-chave: Orchards; Sprayers; Drift; Service pressure.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400020