large systematic error
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2020 ◽  
Vol 75 (1) ◽  
pp. 107-114
Author(s):  
Rasmus L. Pedersen ◽  
Anna-Lena Sahlberg ◽  
Dina Hot ◽  
Zhongshan Li

It has previously been demonstrated that the ratio of the degenerate four wave mixing signal from two hot water line groups near 3231 cm–1 can be used for seedless flame temperature measurements. This paper presents an investigation of the impact of saturation effects on the measured signal intensity from each line group, as well as an estimation of the accuracy of the method. The saturation effects observed here would result in a large systematic error if they are not taken into account when using the degenerate four-wave mixing intensity of these water line groups to calculate the flame temperature.


2020 ◽  
Vol 2020 (7) ◽  
Author(s):  
Yutaro Akahoshi ◽  
Sinya Aoki ◽  
Tatsumi Aoyama ◽  
Takumi Doi ◽  
Takaya Miyamoto ◽  
...  

Abstract We investigate the HAL QCD potential in $I=1$$\pi \pi$ scattering using the hybrid method for all-to-all propagators, in which a propagator is approximated by low eigenmodes, and the remaining high-eigenmode part is stochastically estimated. To verify the applicability of the hybrid method to systems containing quark creation$/$annihilation contributions such as the $\rho$ meson, we calculate the $I=1$$\pi\pi$ potential with the $(2+1)$-flavor gauge configurations on a $16^3 \times 32$ lattice with lattice spacing $a \approx 0.12$ fm and $(m_{\pi},m_{\rho}) \approx (870, 1230)$ MeV, in which the $\rho$ meson appears as a deeply bound state. While we find that the naive stochastic evaluations for quark creation$/$annihilation contributions lead to extremely large statistical fluctuations, additional noise reduction methods enable us to obtain a sufficiently precise potential, which shows a strong attractive force. We also confirm that the binding energy and $k^3 \cot \delta$ obtained from our potential are roughly consistent with an existing $\rho$ meson bound state, within the large systematic error associated with our calculation, whose possible origin is also discussed.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2245 ◽  
Author(s):  
Tomas Johannisson

Background.Different individuals have alpha waves with different wavelengths. The distribution of the wavelengths is assumed to be bell-shaped and smooth. Although this view is generally accepted, it is still just an assumption and has never been critically tested. When exploring the relationship between alpha waves and personality traits, it makes a huge difference if the distribution of the alpha waves is smooth or if specific groups of alpha waves can be demonstrated. Previous studies have not considered the possibility that specific groups of alpha waves may exist.Methods.Computerized EEGs have become standard, but wavelength measurements are problematic when based on averaging procedures using the Fourier transformation because such procedures cause a large systematic error. If the actual wavelength is of interest, it is necessary to go back to basic physiology and use raw EEG signals. In the present study, measurements were made directly from sequences of alpha waves where every wave could be identified. Personality dimensions were measured using an inventory derived from the International Personality Item Pool.Results.Recordings from 200 healthy individuals revealed that there are three main groups of alpha waves. These groups had frequencies around 8, 10, and 12 waves per second. The middle group had a bimodal distribution, and a subdivision gave a total of four alpha groups. In the center of each group, the degree of extraversion was high and the degree of neuroticism was low. Many small differences in personality traits were found when the centers were compared with one another. This gave four personality profiles that resemble the four classical temperaments. When people in the surrounding zones were compared with those in the centers, relatively large differences in personality traits were found.Conclusions.Specific groups of alpha waves exist, and these groups have to be taken into account when correlations are made to personality dimensions and temperament types. There is a link between alpha waves and personality traits, and this link implies that there is an underlying relationship. To explain the nature of this relationship, there are two hypotheses that can be applied. One of these deals with the general organization of the forebrain and the other explains why the brain generates alpha waves.


2008 ◽  
Vol 8 (21) ◽  
pp. 6375-6380 ◽  
Author(s):  
A. E. Bourassa ◽  
D. A. Degenstein ◽  
E. J. Llewellyn

Abstract. Recent work has shown that the retrieval of stratospheric aerosol vertical profiles is possible using limb scattered sunlight measurements at optical wavelengths. The aerosol number density profile is retrieved for an assumed particle size distribution and composition. This result can be used to derive the extinction at the measured wavelength. However, large systematic error can result from the uncertainty in the assumed size distribution when the result is used to estimate the extinction at other wavelengths. It is shown in this work that the addition of information obtained from the near infrared limb radiance profile at 1530 nm measured by the imaging module of the OSIRIS instrument yields an indication of the aerosol size distribution profile that can be used to improve the fidelity of the retrievals. A comparison of the estimated extinction profile at 1020 nm with two coincident occultation measurements demonstrates agreement to within approximately 15% from 12 to 27 km altitude.


2008 ◽  
Vol 132 (11) ◽  
pp. 1781-1785
Author(s):  
Stanley F. Lo ◽  
Bernadine Jendrzejczak ◽  
Basil T. Doumas

Abstract Context.—In 2003 the Chemistry Resource Committee of the College of American Pathologists introduced a commutable specimen in the Neonatal Bilirubin Surveys. This specimen was intended to help evaluate all bilirubin methods. Objective.—To evaluate the effect of commutable specimens on the performance of selected clinical analyzers in measuring neonatal bilirubin from 2003 through 2006. Design.—A human serum–based specimen enriched with unconjugated bilirubin in human serum has been included since 2003 in the Neonatal Bilirubin Surveys. The bilirubin values of these specimens were determined by the reference method and used to evaluate results reported by various chemistry analyzers. Results.—Coefficients of variation for College of American Pathologists All Data ranged from 4.9% to 6.2% for the Neonatal Bilirubin Survey. However, coefficients of variation for the 4 major instrument groups (Dimension, Olympus, Synchron, and Vitros), which report 65% of all results, varied from 2% to 3%. College of American Pathologists All Data mean bilirubin values were within 0.46 mg/dL (7.8 μmol/L) of the reference method mean in 2003; in subsequent years these differences became larger, peaking at 1.87 mg/dL (32 μmol/L) in 2005. Conclusions.—The large systematic error of bilirubin measurements is due primarily to failure of instrument manufacturers to produce reliable bilirubin calibrators. Primary calibrators should consist of human serum enriched with unconjugated bilirubin. Bilirubin values must be assigned by the reference method, the performance and robustness of which are reported in this article. Secondary calibrators distributed to users must be traceable to primary calibrators.


2008 ◽  
Vol 8 (1) ◽  
pp. 4001-4016 ◽  
Author(s):  
A. E. Bourassa ◽  
D. A. Degenstein ◽  
E. J. Llewellyn

Abstract. Recent work has shown that the retrieval of stratospheric aerosol vertical profiles is possible using limb scattered sunlight measurements at optical wavelengths. The aerosol number density profile is retrieved for an assumed particle size distribution and composition. This result can be used to derive the extinction at the measured wavelength. However, large systematic error can result from the uncertainty in the assumed size distribution when the result is used to estimate the extinction at other wavelengths. It is shown in this work that the addition of information obtained from the near infrared limb radiance profile at 1530 nm measured by the imaging module of the OSIRIS instrument yields an indication of the aerosol size distribution profile that can be used to improve the fidelity of the retrievals. A comparison of the estimated extinction profile at 1020 nm with coincident occultation measurements demonstrates agreement to within approximately 15% from 12 to 27 km altitude.


2003 ◽  
Vol 16 (14) ◽  
pp. 2385-2395 ◽  
Author(s):  
Robert E. Eskridge ◽  
James K. Luers ◽  
C. R. Redder

Abstract Inhomogeneities in U.S. radiosonde data that used the VIZ and Vaisala RS80 cannot be explained by radiation errors, which can be removed by the heat balance models. WMO intercomparision data, modeling results, temperature time series, and 1200 minus 0000 UTC temperature differences are examined to show that there appears to be an error in the U.S. RS80/RSN93 temperature correction software. Radiosonde soundings taken at U.S. stations that launch Vaisala RS80 radiosondes, which are integrated within the National Weather Service (NWS) Microcomputer Automatic Radio-Theodolite (Micro-ART) system, should not be used in climate studies since there is a large systematic error of unknown origin in the temperature data. This paper is the first of two and is primarily concerned with the midtroposphere. The second paper discusses the large unexplained 0000 and 1200 UTC differences in the stratosphere.


Metrologia ◽  
1996 ◽  
Vol 33 (2) ◽  
pp. 155-160 ◽  
Author(s):  
H Hanada ◽  
T Tsubokawa ◽  
S Tsuruta

1986 ◽  
Vol 109 ◽  
pp. 213-221
Author(s):  
C A Murray ◽  
P M Corben ◽  
R W Argyle

In continuation of a long term programme of measurement of parallaxes and proper motions in the South Galactic Cap from plates taken with the UK Schmidt Telescope and measured in GALAXY at RGO, data for some 800 red stars brighter than B = 17.5 have been derived from two independent plate series. The parallaxes obtained from unfiltered IIaO plates show a large systematic error depending on magnitude compared with those obtained from IIaD plates with GG 495 filter. After correction, the combined trigonometric parallaxes show very satisfactory agreement with photometric parallaxes, and the average r.m.s. error of a combined parallax is found to be about ±0″.012 both from internal and external evidence.


1980 ◽  
Vol 63 (2) ◽  
pp. 194-199 ◽  
Author(s):  
James M Vahl ◽  
Jean E Converse ◽  
◽  
A A Andreasen ◽  
J H Barnett ◽  
...  

Abstract Twenty-three laboratories analyzed 5 replicate wine samples according to a specified version of the Ripper direct iodometric titration for sulfur dioxide. Each sample was analyzed for (A) free S02, (B) total S02, and (C) iodine-reactive substances other than S02. Although variations of A with temperature and of A and B with time of analysis were anticipated, analysis of covariance showed no significant reduction in error when these variables were taken into account. Error did vary with S02 level and wine type, red vs white. Pooled estimates of precision (withinlaboratory error) in mg S02/L wine were, for white wine: (A) 3.3, (B) 10.4, (C) 1.9; for red wine: (A) 3.8, (B) 7.3, (C) 1.9. Pooled estimates of systematic (between-laboratory) error in mg SO2/L wine were, for white wine: (A) 2.7, (B) 16.6, (C) 2.1; for red wine: (A) 4.3, (B) 15.1, (C) 3.0. Although rapid and convenient, the Ripper method is severely limited by poor precision and large systematic error. The Ripper method is not recommended for adoption by the AOAC.


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