Estimation of the extrapolation error in the calibration of type S thermocouples

2013 ◽  
Author(s):  
P. Giorgio ◽  
K. M. Garrity ◽  
M. Jiménez Rebagliati ◽  
J. García Skabar
Keyword(s):  
Extrapolation Error

scholarly journals Asymptotic behavior of the extrapolation error associated with the estimation of extreme quantiles

Extremes ◽  
2020 ◽  
Vol 23 (2) ◽  
pp. 349-380
Author(s):  
Clément Albert ◽  
Anne Dutfoy ◽  
Stéphane Girard
Keyword(s):  
Asymptotic Behavior ◽  
Extreme Quantiles ◽  
Extrapolation Error

Discussion on Extrapolation Error in Peak Floods for the Rivers Ganga and Yamuna

1998 ◽  
Vol 4 (2) ◽  
pp. 64-64
Author(s):  
Mohd Jamil ◽  
M. M. Ashhar ◽  
M. Muzzamil ◽  
G. Sharma ◽  
K. D. Nambudripad
Keyword(s):  
Extrapolation Error

scholarly journals Design of Tracking, Telemetry, Command (TT&C) and Data Transmission Integrated Signal in TDD Mode

2020 ◽  
Vol 12 (20) ◽  
pp. 3340
Author(s):  
Linshan Xue ◽  
Xue Li ◽  
Weiren Wu ◽  
Yikang Yang
Keyword(s):  
High Precision ◽  
Data Transmission ◽  
Measurement Technology ◽  
Complex Frequency ◽  
High Precision Measurement ◽  
Network Nodes ◽  
Time Frequency ◽  
Transmission Equipment ◽  
And Control ◽  
Extrapolation Error

For satellite or aircraft networks, tracking, telemetry, and control (TT&C) and data transmission between different nodes are necessary. Traditional measurement mostly adopts the frequency division duplex (FDD) mode and uses a continuous measurement system to achieve high-precision measurement. However, as the number of network nodes increases, the mode suffers from complex frequency domain allocation, and high-cost measurement and data transmission equipment is required. This paper proposes the integrated signal in time division duplex (TDD) mode to improve frequency utilization to address these circumstances. The proposed signal can transmit the TT&C and data at the same frequency. In addition, the high-precision time-frequency synchronization and relative measurement technology in the TDD mode for distributed spacecraft or aircraft networks are studied. The simulation results show that the signal can work normally when the Doppler extrapolation error is less than a quarter of the integration frequency. The distance extrapolation error should be less than a quarter of the length of a chip. The integrated signal reduces the frequency band occupation and realizes the integration of TT&C and data transmission. In addition, the measurement performance is reduced by only 2~3 dB compared with that of the traditional pure TT&C signal.

scholarly journals Monitoring geomagnetic information in the territory of Croatia

Geofizika ◽  
2019 ◽  
Vol 36 (1) ◽  
pp. 1-15
Author(s):  
Mario Brkić
Keyword(s):  
Annual Variation ◽  
Original Data ◽  
Time Span ◽  
Series Length ◽  
Annual Variations ◽  
Repeat Station ◽  
Observatory Data ◽  
Model Reliability ◽  
Processing Steps ◽  
Extrapolation Error

In orientation and navigation using compass, reliable map’s marginal information of Earth’s magnetic field declination and its annual variation, namely geomagnetic information (GI), is crucial. Monitoring geomagnetic information means observing declination and its annual variation and checking the reliability of the actual GI model. A typical way of monitoring GI across a national territory involves conducting periodic geomagnetic network surveys to assess and update the model. The objective of the paper was to investigate improving the GI model reliability when an earlier model’s error was raised to standard accuracy, and repeat station network surveys were not yet completed. A series of processing steps in modelling were revised to preserve the original data reliability. The partial 2008.5, 2009.5 and 2010.5 declination solutions were directly reduced to epoch 2015.0, and then to 2016.0, using the IGRF-12 model. The next step was to use 2016 and 2017 quiet daily declination means to estimate corresponding annual variations at surrounding observatories and repeat stations. Normal declination annual variation models were then built for further reductions to epoch 2017.0, and 2018.0, and for forward extrapolations. The quiet days observatory data were analysed to estimate the effect of the input time series length and linear extrapolated time span on forward extrapolation error. Thus, the reliability decline of the initial GI model slowed down in the sequence of models presented. The final GI2018v2 model, valid for 2018.0–2019.0, proved reliable in comparison to the repeat station declination observations of 2018.

scholarly journals Morphology of GPS and DPS TEC over an equatorial station: validation of IRI and NeQuick 2 models

2018 ◽  
Vol 36 (5) ◽  
pp. 1457-1469 ◽  
Author(s):  
Olumide Olayinka Odeyemi ◽  
Jacob Adeniyi ◽  
Olushola Oladipo ◽  
Olayinka Olawepo ◽  
Isaac Adimula ◽  
...  
Keyword(s):  
Solar Activity ◽  
Electron Content ◽  
Total Electron ◽  
Equatorial Station ◽  
Significant Percentage ◽  
Gps Tec ◽  
Rate Of Increase ◽  
June Solstice ◽  
Better Than ◽  
Extrapolation Error

Abstract. We investigated total electron content (TEC) at Ilorin (8.50∘ N 4.65∘ E, dip lat. 2.95) for the year 2010, a year of low solar activity in 2010 with Rz=15.8. The investigation involved the use of TEC derived from GPS, estimated TEC from digisonde portable sounder data (DPS), and the International Reference Ionosphere (IRI) and NeQuick 2 (NeQ) models. During the sunrise period, we found that the rate of increase in DPS TEC, IRI TEC, and NeQ TEC was higher compared with GPS TEC. One reason for this can be attributed to an overestimation of plasmaspheric electron content (PEC) contribution in modeled TEC and DPS TEC. A correction factor around the sunrise, where our finding showed a significant percentage deviation between the modeled TEC and GPS TEC, will correct the differences. Our finding revealed that during the daytime when PEC contribution is known to be absent or insignificant, GPS TEC and DPS TEC in April, September, and December predict TEC very well. The lowest discrepancies were observed in May, June, and July (June solstice) between the observed values and all the model values at all hours. There is an overestimation in DPS TEC that could be due to extrapolation error while integrating from the peak electron density of F2 (NmF2) to around ∼1000 km in the Ne profile. The underestimation observed in NeQ TEC must have come from the inadequate representation of contribution from PEC on the topside of the NeQ model profile, whereas the exaggeration of PEC contribution in IRI TEC amounts to overestimation in GPS TEC. The excess bite-out observed in DPS TEC and modeled TEC indicates over-prediction of the fountain effect in these models. Therefore, the daytime bite-out observed in these models requires a modifier that could moderate the perceived fountain effect morphology in the models accordingly. The daytime DPS TEC performs better than the daytime IRI TEC and NeQ TEC in all the months. However, the dusk period requires attention due to the highest percentage deviation recorded, especially for the models, in March, November, and December. Seasonally, we found that all the TECs maximize and minimize during the March equinox and June solstice, respectively. Therefore, GPS TEC and modeled TEC reveal the semiannual variations in TEC.

EXTRAPOLATION ERROR IN PEAK FLOODS FOR THE RIVERS GANGA AND YAMUNA

1998 ◽  
Vol 4 (1) ◽  
pp. 16-23
Author(s):  
Mohd. Jamil ◽  
M. M. Ashhar ◽  
M. Muzzammil ◽  
G. Sharma
Keyword(s):  
Extrapolation Error
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