On Random Reynolds Roughness

1987 ◽  
Vol 109 (3) ◽  
pp. 427-431 ◽  
Author(s):  
R. F. Gans
Keyword(s):  
Standard Deviation ◽  
Fourth Power ◽  
Smooth Base

Lubricant fluxes and lubrication forces have been calculated for statistical realizations of a piecewise planar slider running over a smooth base with an incompressible lubricant. The statistics of the response are not simply related to those of the roughness. The standard deviation of the force increases approximately as the fourth power of the roughness deviation for probable contact situations.

Nucleic Acid Molecules Prepared by Monolayer Techniques

1972 ◽  
Vol 30 ◽  
pp. 178-179
Author(s):  
Dimitrij Lang
Keyword(s):  
Electron Microscopy ◽  
Standard Deviation ◽  
Nucleic Acid ◽  
Cytochrome C ◽  
Nucleic Acids ◽  
Contour Length ◽  
Sample Standard Deviation ◽  
Molecular Weights ◽  
Length Measurements ◽  
Protein Monolayer

The success of the protein monolayer technique for electron microscopy of individual DNA molecules is based on the prevention of aggregation and orientation of the molecules during drying on specimen grids. DNA adsorbs first to a surface-denatured, insoluble cytochrome c monolayer which is then transferred to grids, without major distortion, by touching. Fig. 1 shows three basic procedures which, modified or not, permit the study of various important properties of nucleic acids, either in concert with other methods or exclusively:1) Molecular weights relative to DNA standards as well as number distributions of molecular weights can be obtained from contour length measurements with a sample standard deviation between 1 and 4%.

Reliability of the Minimum Masking Level as Outcome Variable in Tinnitus Clinical Research

2020 ◽  
Vol 29 (3) ◽  
pp. 429-435
Author(s):  
Patricia C. Mancini ◽  
Richard S. Tyler ◽  
Hyung Jin Jun ◽  
Tang-Chuan Wang ◽  
Helena Ji ◽  
...  
Keyword(s):  
Standard Deviation ◽  
High Frequency ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Outcome Variable ◽  
Reliable Estimate ◽  
Moderate Correlation ◽  
Trained Subjects ◽  
The Relationship ◽  
Minimum Intensity

Purpose The minimum masking level (MML) is the minimum intensity of a stimulus required to just totally mask the tinnitus. Treatments aimed at reducing the tinnitus itself should attempt to measure the magnitude of the tinnitus. The objective of this study was to evaluate the reliability of the MML. Method Sample consisted of 59 tinnitus patients who reported stable tinnitus. We obtained MML measures on two visits, separated by about 2–3 weeks. We used two noise types: speech-shaped noise and high-frequency emphasis noise. We also investigated the relationship between the MML and tinnitus loudness estimates and the Tinnitus Handicap Questionnaire (THQ). Results There were differences across the different noise types. The within-session standard deviation averaged across subjects varied between 1.3 and 1.8 dB. Across the two sessions, the Pearson correlation coefficients, range was r = .84. There was a weak relationship between the dB SL MML and loudness, and between the MML and the THQ. A moderate correlation ( r = .44) was found between the THQ and loudness estimates. Conclusions We conclude that the dB SL MML can be a reliable estimate of tinnitus magnitude, with expected standard deviations in trained subjects of about 1.5 dB. It appears that the dB SL MML and loudness estimates are not closely related.

Bedingungen für den Erfolg übergewichtiger und adipöser Kinder in einem ambulanten Programm zur Gewichtsreduktion durch Veränderungen des Lebensstils

2010 ◽  
Vol 38 (5) ◽  
pp. 351-360 ◽  
Author(s):  
Wilfried Pott ◽  
Georg Fröhlich ◽  
Özgür Albayrak ◽  
Johannes Hebebrand ◽  
Ursula Pauli-Pott
Keyword(s):  
Body Mass Index ◽  
Standard Deviation ◽  
Body Mass ◽  
Standard Deviation Score ◽  
Psychische Belastung ◽  
Deviation Score ◽  
Höheres Alter

Fragestellung: Es wurde der Frage nachgegangen, ob sich erfolgreiche Teilnehmer eines ambulanten familienzentrierten Gewichtskontrollprogramms durch spezifische familiäre und psychologische Charakteristiken auszeichnen. Einbezogen wurden die psychosoziale Risikobelastung der Familie, Depressivität und Bindungsstil der Hauptbezugsperson, der Body mass index (BMI) und der BMI-Standardabweichungswert («Standard deviation score», SDS) des teilnehmenden Kindes und der Familienmitglieder sowie die individuelle psychische Belastung des teilnehmenden Kindes. Methodik: Die Daten wurden per Interview und Fragebogen vor dem Behandlungsbeginn erhoben. Von 136 in das Programm aufgenommenen übergewichtigen und adipösen Kindern zwischen 7 und 15 Jahren beendeten 116 das 12-monatige Interventionsprogramm. Von diesen zeigten 100 (85,3 %) eine Reduktion des BMI-SDS und 79 (68.1 %) eine mehr als 5 %ige Reduktion des BMI-SDS. Diese «erfolgreichen» Kinder wurden mit 56 «nicht erfolgreichen» (Abbrecher und Kinder mit einer 5 %igen oder geringeren Reduktion des BMI-SDS) verglichen. Ergebnisse: Nicht erfolgreiche Kinder unterschieden sich von den erfolgreichen durch ein höheres Alter, eine höhere psychosoziale Risikobelastung, Depressivität und einen vermeidenden Bindungsstil der Mutter sowie durch das Vorhandensein adipöser Geschwister. In einer logistischen Regressionsanalyse zeigten sich mütterliche Depressivität und das Vorhandensein adipöser Geschwister als beste und voneinander unabhängige Prädiktoren. Schlussfolgerungen: Um die spezifischen Bedürfnisse der Familien zu erfüllen und einen Misserfolg zu verhindern, sollten zusätzliche Programmbausteine zur spezifischen Unterstützung von Jugendlichen mit adipösen Geschwistern und Müttern mit Depressionen und vermeidenden Bindungsstil entwickelt werden. Die Wirksamkeit dieser Module muss dann in weiteren Studien überprüft werden.

At Least One Standard Deviation Above the Mean

1969 ◽  
Vol 14 (9) ◽  
pp. 470-471
Author(s):  
M. DAVID MERRILL
Keyword(s):  
Standard Deviation ◽  
The Mean

Analysis of Myocardial Time-Activity Curves of 123l-Heptadecanoic Acid II. The Acquisition Time

1987 ◽  
Vol 26 (06) ◽  
pp. 248-252 ◽  
Author(s):  
M. J. van Eenige ◽  
F. C. Visser ◽  
A. J. P. Karreman ◽  
C. M. B. Duwel ◽  
G. Westera ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Acquisition Time ◽  
Half Time ◽  
Constant Ratio ◽  
Time Activity ◽  
Time Activity Curve ◽  
Time Value ◽  
Activity Curve ◽  
Low Amplitude ◽  
Parameter Values

Optimal fitting of a myocardial time-activity curve is accomplished with a monoexponential plus a constant, resulting in three parameters: amplitude and half-time of the monoexponential and the constant. The aim of this study was to estimate the precision of the calculated parameters. The variability of the parameter values as a function of the acquisition time was studied in 11 patients with cardiac complaints. Of the three parameters the half-time value varied most strongly with the acquisition time. An acquisition time of 80 min was needed to keep the standard deviation of the half-time value within ±10%. To estimate the standard deviation of the half-time value as a function of the parameter values, of the noise content of the time-activity curve and of the acquisition time, a model experiment was used. In most cases the SD decreased by 50% if the acquisition time was increased from 60 to 90 min. A low amplitude/constant ratio and a high half-time value result in a high SD of the half-time value. Tables are presented to estimate the SD in a particular case.

Using Connectionist Modules for Decision Support

1990 ◽  
Vol 29 (03) ◽  
pp. 167-181 ◽  
Author(s):  
G. Hripcsak
Keyword(s):  
Decision Support ◽  
Standard Deviation ◽  
Confidence Interval ◽  
Posterior Probability ◽  
Back Propagation ◽  
Connectionist Model ◽  
Test Set ◽  
The Third ◽  
Independent Test ◽  
Better Than

AbstractA connectionist model for decision support was constructed out of several back-propagation modules. Manifestations serve as input to the model; they may be real-valued, and the confidence in their measurement may be specified. The model produces as its output the posterior probability of disease. The model was trained on 1,000 cases taken from a simulated underlying population with three conditionally independent manifestations. The first manifestation had a linear relationship between value and posterior probability of disease, the second had a stepped relationship, and the third was normally distributed. An independent test set of 30,000 cases showed that the model was better able to estimate the posterior probability of disease (the standard deviation of residuals was 0.046, with a 95% confidence interval of 0.046-0.047) than a model constructed using logistic regression (with a standard deviation of residuals of 0.062, with a 95% confidence interval of 0.062-0.063). The model fitted the normal and stepped manifestations better than the linear one. It accommodated intermediate levels of confidence well.

The Frequency of Bleeding and Height of Adolescent Haemophiliacs

1979 ◽  
Vol 41 (02) ◽  
pp. 286-290 ◽  
Author(s):  
J L Bem ◽  
M J Painter ◽  
A Aronstam ◽  
J H Patrick ◽  
R E Newcombe
Keyword(s):  
Standard Deviation ◽  
Standard Deviation Score ◽  
Height Standard Deviation Score ◽  
Deviation Score

SummaryThe relation between the height of adolescent haemophiliacs and their bleeding frequency has been studied. 45 haemophiliacs aged 10-19 years were divided into 3 groups: small, medium and tall, using a Height Standard Deviation Score. The average bleeding frequency per 100 days in the group of small haemophiliacs was 8.71 ± SD 4.47, in the medium height group 10.18 ± SD 6.71, while the tall individuals bled in average 15.97 ± SD 3.15 every 100 days. There was no relationship between age and bleeding frequency.

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