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| Registros recuperados: 19 | |
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| Almeida,Niza Helena de; Nohama,Percy. |
| We present a proposal for evaluating and qualifying pH measuring devices based on the requirements of relevant standards. The proposal presented is based on ASTM E70, NBR 7353, JIS Z 8805, BS 3145, DIN 19268, NBR ISO 17025 and other standards, as well as the results of field research carried out in conjunction with professionals performing pH measurements in public health laboratories. Evaluation is performed by inspection of a form which records data from the measuring system. The form gives acceptable variations in the parameters being tested and allows a conclusion to be reached regarding acceptability of the system. Using the proposed protocol allows definition of suitable analysis criteria, while taking into account the influence pH measurement is... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Quality control; PH measurement; Instrumentation. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000200005 |
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| Silva,Irenilson M. da; Pandorfi,Héliton; Vasconcelos,Ângelo J. S. de; Laurenti,Renato; Guiselini,Cristiane. |
| Due to the importance of the environment on animal production and thus environmental control, the study aims to build a system for monitoring and control the meteorological variables, temperature and relative humidity, low cost, which can be associated with an evaporative cooling system (ECS). The system development included all the stages of assembly, test and laboratory calibration, and later the validation of the equipment carried in the field. The validation step showed results which allowed concluding that the system can be safely used in the monitoring of these variables. The controller was efficient in management of the microclimate in the waiting corral and allowed the maintenance of the air temperature within the comfort range for dairy cattle in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dairy cattle; Thermal comfort; Instrumentation. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000100001 |
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| Leite,Daniel M.; Fernandes,Haroldo C.; Teixeira,Mauri M.; Cecon,Paulo R.; Furtado Júnior,Marconi R.. |
| ABSTRACT The objective of this study was to evaluate and model the traction performance parameters of a tractor 4x2 FWD, according to the tractor speed, the internal pressure and the type of tires construction. For each type of tire construction was assembled an experiment in which we evaluated the influence of internal pressures of the front and rear tires and the speed of the mechanical assembly. It was found that the sliding of the diagonal run, presented significant effect in all variables analyzed, since the radial showed no influence of the factors evaluated. The power available in the drawbar was higher when the tractor was equipped for radial tires. The response variables, fuel consumption schedule and specific fuel consumption were more sensitive... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Harrow disc; Instrumentation; Traction performance. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000300484 |
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| Andre, Xavier; Moreau, Bertrand; Le Reste, Serge. |
| The scientific community observes the ocean for applications in the fields of oceanography and climate research. In order to recover in situ data, more than 3,000 profiling floats are operated in the framework of the Argo Program. Each float performs cycles between the sea surface and a depth of 2,000 meters. Scientific data are gathered while the float is travelling upward from the depths of the oceans, and are then transmitted via a satellite communication system at the end of each cycle. During its time at the surface, mainly dedicated to transmissions, the float is vulnerable and subject to drift, which limits its use in many studies. Moreover, transmission times are becoming longer due to a trend towards high resolution or multi-sensor profiles.... |
| Tipo: Text |
Palavras-chave: Buoy observations; In situ oceanic observations; Instrumentation; Sensors; Profilers; Oceanic. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00284/39519/38011.pdf |
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| Moore, Sw. |
| The physical structure of coral reefs, like that of rainforests and other spatially-complex ecosystems, modulates light, fluid flow, and other physical variables to create a spatially and temporally complex mosaic of microhabitats. Accurate and affordable methods for quantifying this spatio-temporal variation are required to address many basic and applied research questions related to the ecology and management of reefs. Recent advances in semiconductor electronics technology have made it easier and much less expensive to build small and reliable datalogging instruments, which can be deployed in arrays to record spatio-temporal patterns of ecologically-important variables. Suitable instruments are already commercially available for $100 (US) or less per... |
| Tipo: Text |
Palavras-chave: Instrumentation; Habitat; Écologie physique; Électronique; Instrumentation; Habitat characterization; Physical ecology; Electronics. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43592/44033.pdf |
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| Charrassin, J. -b.; Hindell, M.; Rintoul, S. R.; Roquet, Fabien; Sokolov, S.; Biuw, M.; Costa, D.; Boehme, L.; Lovell, P.; Coleman, R.; Timmermann, R.; Meijers, A.; Meredith, M.; Park, Y. -h.; Bailleul, F.; Goebel, M.; Tremblay, Y; Bost, C. -a.; Mcmahon, C. R.; Field, I. C.; Fedak, M. A.; Guinet, C. |
| Polar regions are particularly sensitive to climate change, with the potential for significant feedbacks between ocean circulation, sea ice, and the ocean carbon cycle. However, the difficulty in obtaining in situ data means that our ability to detect and interpret change is very limited, especially in the Southern Ocean, where the ocean beneath the sea ice remains almost entirely unobserved and the rate of sea-ice formation is poorly known. Here, we show that southern elephant seals (Mirounga leonina) equipped with oceanographic sensors can measure ocean structure and water mass changes in regions and seasons rarely observed with traditional oceanographic platforms. In particular, seals provided a 30-fold increase in hydrographic profiles from the sea-ice... |
| Tipo: Text |
Palavras-chave: Antarctic circumpolar current; Instrumentation; Marine predators; Ocean observation; Sea-ice modeling. |
| Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00241/35239/33750.pdf |
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| Reverdin, G.; Boutin, J.; Martin, N.; Lourenco, A.; Bouruet-aubertot, P.; Lavin, A.; Mader, J.; Blouch, P.; Rolland,; Gaillard, Fabienne; Lazure, Pascal. |
| The accuracy of temperature measurements from drifters is first examined for 16 drifters (manufactured either by Metocean Data Systems or by Pacific Gyre) deployed with two temperature sensors in the tropical or North Atlantic Ocean. One of these sensors is the SST thermistor commonly used on Surface Velocity Program (SVP) drifters since the late 1980s; whereas the other sensor is a platinum temperature probe associated with a Seabird conductivity cell. The authors find (for 19 separate deployments) an average positive offset of the SST thermistor measurements in 17 out of 19 cases, exceeding 0.1 degrees C in five instances. Among the five drifters that were at sea for a year or more, two present a large trend in this offset (0.10 degrees and -0.10 degrees... |
| Tipo: Text |
Palavras-chave: Temperature; Sea surface temperature; Instrumentation; Sensors. |
| Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00012/12327/9112.pdf |
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| Mensah, Vigan; Roquet, Fabien; Siegelman-charbit, Lia; Picard, Baptiste; Pauthenet, Etienne; Guinet, Christophe. |
| The effect of thermal mass on the salinity estimate from conductivity-temperature-depth (CTD) tags sensor mounted on marine mammals is documented, and a correction scheme is proposed to mitigate its impact. The algorithm developed here allows for a direct correction of the salinity data, rather than a correction of the sample's conductivity and temperature. The amplitude of the thermal mass-induced error on salinity and its correction are evaluated via comparison between data from CTD tags and from Sea-Bird Scientific CTD used as a reference. Thermal mass error on salinity appears to be generally O(10(-2)) g kg(-1), it may reach O(10(-1)) g kg(-1), and it tends to increase together with the magnitude of the cumulated temperature gradient (T-HP) within the... |
| Tipo: Text |
Palavras-chave: Data processing; In situ oceanic observations; Instrumentation; Sensors; Profilers; Oceanic. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00585/69697/67577.pdf |
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| Moreira,Wagner Henrique; Tormena,Cássio Antônio; Betioli Junior,Edner; Figueiredo,Getulio Coutinho; Silva,Álvaro Pires da; Giarola,Neyde Fabíola Balarezo. |
| The least limiting water range (LLWR) has been used as an indicator of soil physical quality as it represents, in a single parameter, the soil physical properties directly linked to plant growth, with the exception of temperature. The usual procedure for obtaining the LLWR involves determination of the water retention curve (WRC) and the soil resistance to penetration curve (SRC) in soil samples with undisturbed structure in the laboratory. Determination of the WRC and SRC using field measurements (in situ ) is preferable, but requires appropriate instrumentation. The objective of this study was to determine the LLWR from the data collected for determination of WRC and SRC in situ using portable electronic instruments, and to compare those determinations... |
| Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Water content; Instrumentation; Critical bulk density; Soil physical quality; Matric potential. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000600012 |
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| Ponciano,Isaac de M.; Miranda,Jarbas H. de; Cooke,Richard A.; Grah,Vanessa de F.; Silva,Alisson J. P. da. |
| ABSTRACT Despite the growing use of the time domain reflectometry (TDR) technique to monitoring ions in the soil solution, there are few studies that provide insight into measurement error. To overcome this lack of information, a methodology, based on the central limit theorem error, was used to quantify the uncertainty associated with using the technique to estimate potassium ion concentration in two soil types. Mathematical models based on electrical conductivity and soil moisture derived from TDR readings were used to estimate potassium concentration, and the results were compared to potassium concentration determined by flame spectrophotometry. It was possible to correct for random and systematic errors associated with TDR readings, significantly... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Central limit theorem; Instrumentation; Electrical conductivity. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000400343 |
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| Pessoa,José Dalton Cruz; Leeuwen,Johannes Van. |
| The kernel of the cutia nut (castanha-de-cutia, Couepia edulis (Prance) Prance) of the western Amazon, which is consumed by the local population, has traditionally been extracted from the nut with a machete, a dangerous procedure that only produces kernels cut in half. A shelling off machine prototype, which produces whole kernels without serious risks to its operator, is described and tested. The machine makes a circular cut in the central part of the fruit shell, perpendicular to its main axis. Three ways of conditioning the fruits before cutting were compared: (1) control; (2) oven drying immediately prior to cutting; (3) oven drying, followed by a 24-hour interval before cutting. The time needed to extract and separate the kernel from the endocarp and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Instrumentation; Nut; Kernel; Shelling; Extraction method; Amazon. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452006000200018 |
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| Registros recuperados: 19 | |
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