scholarly journals Comparison of Iohexol Plasma Clearances Calculated From 5 Early-Compartment Correction Equations With Urinary Clearance of Iohexol

2020 ◽  
Vol 5 (10) ◽  
pp. 1842-1843
Author(s):  
Thomas Stehlé ◽  
Khalil El Karoui ◽  
Vincent Audard ◽  
Dominique Prié
Keyword(s):  
Correction Equations

scholarly journals Correction equations to estimate body fat with plicometer WCS dual hand

2017 ◽  
Vol 33 (4) ◽  
pp. 285-292
Author(s):  
Hiago Augusto Zonatto ◽  
Marcelo Romanovitch Ribas ◽  
Eduardo Bolicenha Simm ◽  
André Gonçalves de Oliveira ◽  
Julio Cesar Bassan
Keyword(s):  
Body Fat ◽  
Correction Equations

scholarly journals Laboratory Evaluations of Correction Equations with Multiple Choices for Seed Low-Cost Particle Sensing Devices in Sensor Networks

Sensors ◽  
2020 ◽  
Vol 20 (13) ◽  
pp. 3661 ◽  
Author(s):  
Wen-Cheng Vincent Wang ◽  
Shih-Chun Candice Lung ◽  
Chun Hu Liu ◽  
Chen-Kai Shui
Keyword(s):  
Sensor Networks ◽  
Low Cost ◽  
Before And After ◽  
Sensor Signals ◽  
Research Grade ◽  
Areas Of Interest ◽  
Equivalent Method ◽  
Correction Equations ◽  
Practical Recommendations

To tackle the challenge of the data accuracy issues of low-cost sensors (LCSs), the objective of this work was to obtain robust correction equations to convert LCS signals into data comparable to that of research-grade instruments using side-by-side comparisons. Limited sets of seed LCS devices, after laboratory evaluations, can be installed strategically in areas of interest without official monitoring stations to enable reading adjustments of other uncalibrated LCS devices to enhance the data quality of sensor networks. The robustness of these equations for LCS devices (AS-LUNG with PMS3003 sensor) under a hood and a chamber with two different burnt materials and before and after 1.5 years of field campaigns were evaluated. Correction equations with incense or mosquito coils burning inside a chamber with segmented regressions had a high R2 of 0.999, less than 6.0% variability in the slopes, and a mean RMSE of 1.18 µg/m3 for 0.1–200 µg/m3 of PM2.5, with a slightly higher RMSE for 0.1–400 µg/m3 compared to EDM-180. Similar results were obtained for PM1, with an upper limit of 200 µg/m3. Sensor signals drifted 19–24% after 1.5 years in the field. Practical recommendations are given to obtain equations for Federal-Equivalent-Method-comparable measurements considering variability and cost.

scholarly journals Behavior of the Correction Equations in the Jacobi–Davidson Method

2019 ◽  
Vol 2019 ◽  
pp. 1-4 ◽  
Author(s):  
Yuan Kong ◽  
Yong Fang
Keyword(s):  
Iteration Method ◽  
Convergence Property ◽  
Hermitian Matrices ◽  
Davidson Method ◽  
Different Types ◽  
Correction Equations

The Jacobi–Davidson iteration method is efficient for computing several eigenpairs of Hermitian matrices. Although the involved correction equation in the Jacobi–Davidson method has many developed variants, the behaviors of them are not clear for us. In this paper, we aim to explore, theoretically, the convergence property of the Jacobi–Davidson method influenced by different types of correction equations. As a by-product, we derive the optimal expansion vector, which imposed a shift-and-invert transform on a vector located in the prescribed subspace, to expand the current subspace.

scholarly journals Catch Characteristics of Precipitation Gauges in High-Latitude Regions with High Winds

2006 ◽  
Vol 7 (5) ◽  
pp. 984-994 ◽  
Author(s):  
Konosuke Sugiura ◽  
Tetsuo Ohata ◽  
Daqing Yang
Keyword(s):  
Wind Speed ◽  
High Latitude ◽  
Cold Climate ◽  
Strong Wind ◽  
Blowing Snow ◽  
High Wind ◽  
Wind Speeds ◽  
Solid Precipitation ◽  
High Winds ◽  
Correction Equations

Abstract Intercomparison of solid precipitation measurement at Barrow, Alaska, has been carried out to examine the catch characteristics of various precipitation gauges in high-latitude regions with high winds and to evaluate the applicability of the WMO precipitation correction procedures. Five manual precipitation gauges (Canadian Nipher, Hellmann, Russian Tretyakov, U.S. 8-in., and Wyoming gauges) and a double fence intercomparison reference (DFIR) as an international reference standard have been installed. The data collected in the last three winters indicates that the amount of solid precipitation is characteristically low, and the zero-catch frequency of the nonshielded gauges is considerably high, 60%–80% of precipitation occurrences. The zero catch in high-latitude high-wind regions becomes a significant fraction of the total precipitation. At low wind speeds, the catch characteristics of the gauges are roughly similar to the DFIR, although it is noteworthy that the daily catch ratios decreased more rapidly with increasing wind speed compared to the WMO correction equations. The dependency of the daily catch ratios on air temperature was confirmed, and the rapid decrease in the daily catch ratios is due to small snow particles caused by the cold climate. The daily catch ratio of the Wyoming gauge clearly shows wind-induced losses. In addition, the daily catch ratios are considerably scattered under strong wind conditions due to the influence of blowing snow. This result suggests that it is not appropriate to extrapolate the WMO correction equations for the shielded gauges in high-latitude regions for high wind speed of over 6 m s−1.

A Survey of Mathematical Correction Procedures in X-Ray Spectrometry

1975 ◽  
Vol 19 ◽  
pp. 1-17 ◽  
Author(s):  
Ronald Jenkins
Keyword(s):  
First Principles ◽  
Quantitative Data ◽  
Internal Standard ◽  
Characteristic Line ◽  
X Rays ◽  
Matrix Correction ◽  
Internal Standards ◽  
X Ray ◽  
Correction Equations ◽  
Secondary Fluorescence

X-ray spectrometry is an old technique dating back some sixty-odd years and although most of the early interest revolved around the qualitative aspects of the method it wasn't long before attempts were made to obtain quantitative data. One of the first recorded attempts was that by Coster and von Hevesey who in 1923 accurately determined the amount of hafnium in zirconium using tantalum as an internal standard. Glocker and Schreiber were the first to attempt calculation of X-ray characteristic line intensity from first principles although no attempt was made at that time to correct for secondary fluorescence. In von Hevesey's book, “Chemical Analysis by X-Rays,” published in 1932 , a whole chapter is devoted to what is called “Disturbing effects and their avoidance.” Among the effects discussed were primary and secondary absorbtion and third element effects. Matrix correction equations were developed although most of the quantitative work at that time was done using internal standards.

Globe Temperature and Its Measurement: Requirements and Limitations

2019 ◽  
Vol 63 (7) ◽  
pp. 743-758
Author(s):  
A Virgílio M Oliveira ◽  
António M Raimundo ◽  
Adélio R Gaspar ◽  
Divo A Quintela
Keyword(s):  
Forced Convection ◽  
Environmental Conditions ◽  
Response Times ◽  
Air Velocity ◽  
Globe Temperature ◽  
Different Diameters ◽  
Relative Differences ◽  
Correction Equations

Abstract This study addresses the measurement of the globe temperature. For this purpose, two globe thermometers with different diameters (50 and 150 mm) and a variety of thermal environmental conditions were considered. The assessments of the response times and of the influences of the globe diameter and the air velocity on the measured globe temperatures are discussed. The results of the response times clearly put in evidence that the values usually stated in the literature can be questioned and that longer measurement periods must be considered. In fact, response times >30 min were obtained in 68% of the tests performed. Moreover, differences >20ºC were obtained between the 150 and 50 mm sensors, highlighting the influence of the globe diameter. The analysis of the effect of the air velocity on the globe temperature shows mean relative differences >30% between tests in still air and with the higher air velocity considered (1.81 m s–1). On the basis of measurements carried out with the 50 mm globe, correction equations to the standard globe temperature for both natural and forced convection are proposed.

Temperature Correction on Falling Weight Deflectometer Measurements

2000 ◽  
Vol 1716 (1) ◽  
pp. 30-39 ◽  
Author(s):  
Dar-Hao Chen ◽  
John Bilyeu ◽  
Huang-Hsiung Lin ◽  
Mike Murphy
Keyword(s):  
Close Agreement ◽  
Temperature Correction ◽  
Falling Weight Deflectometer ◽  
Temperature Dependent ◽  
Different Seasons ◽  
Falling Weight ◽  
Correction Equations

Repeated falling weight deflectometer (FWD) tests were conducted at three sites. The tests were conducted at regular intervals for 2 to 3 consecutive days per location, and also done during different seasons in order that the widest possible range of temperatures could be obtained. The influence of cracks on temperature correction was also investigated. Temperature correction equations for deflection and moduli were developed so that users could be allowed to input their own reference temperatures. For all test pads, only the W1 and W2 deflections were found to be significantly affected by temperature. Comparisons with other reported temperature correction equations showed close agreement for deflection, but not for moduli. Tests were also run on cracked locations. Temperature did not affect the response of the cracked pavement as much as it did the intact pavement. Due to the different temperature-dependent characteristics of intact and cracked locations, the equations developed from the intact locations may not be used on cracked locations.

A PRIORI PRESSURE FIELD CONSTRUCTION ITERATIVE METHOD FOR THE SOLUTION OF THE STEADY-STATE NAVIER–STOKES EQUATIONS USING GENERAL FINITE-VOLUME CO-LOCATED GRIDS

2007 ◽  
Vol 04 (04) ◽  
pp. 567-601
Author(s):  
JOSE A. LAMAS
Keyword(s):  
Iterative Method ◽  
Pressure Field ◽  
Stokes Equations ◽  
A Priori ◽  
Mass Conservation ◽  
Momentum Conservation ◽  
Navier Stokes ◽  
Pressure Equation ◽  
Navier Stokes Equations ◽  
Correction Equations

An iterative method has been developed for the solution of the Navier–Stokes equations and implemented using finite volumes with co-located variable arrangement. A pressure equation is obtained combining algebraic momentum and mass conservation equations resulting in a self-consistent set of equations. An iterative procedure solves the pressure equation consistently with mass conservation and then updates velocities based on momentum equations without introducing velocity or pressure correction equations. The process is repeated until velocities satisfy both mass and momentum conservation. Tests demonstrate a priori pressure field solution consistent with mass conservation, and solution of hydrostatic problems in one iteration.

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