Random Errors in Localization of Landmarks in Postero-anterior Cephalograms

This review paper deals with the use of statistical methods to evaluate systematic and random errors associated with trigonometric parallaxes. First, systematic errors which arise when using trigonometric parallaxes to calibrate luminosity systems are discussed. Next, determination of the external errors of parallax measurement are reviewed. Observatory corrections are discussed. Schilt’s point, that as the causes of these systematic differences between observatories are not known the computed corrections can not be applied appropriately, is emphasized. However, modern parallax work is sufficiently accurate that it is necessary to determine observatory corrections if full use is to be made of the potential precision of the data. To this end, it is suggested that a prior experimental design is required. Past experience has shown that accidental overlap of observing programs will not suffice to determine observatory corrections which are meaningful.

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STUDY OF INACCURACY IN THE OPERATION OF THE MAIN CONTROLLER OF STB MACHINE

АГРАРНЫЙ ВЕСТНИК ВЕРХНЕВОЛЖЬЯ ◽

10.35523/2307-5872-2019-27-2-99-102 ◽

2019 ◽

Keyword(s):

Normal Distribution ◽

Stable Process ◽

Random Errors ◽

Actual Length ◽

Experimental Data Processing ◽

Set Up ◽

Main Regulator ◽

Transmission Gear ◽

Selection Of

At production of fabrics, including fabrics for agricultural purpose, an important role is played by the cor-rect adjustment of operation of machine main regulator. The quality of setup of machine main controller is determined by the proper selection of rotation angle of warp beam weaving per one filling thread. In the pro-cess of using the regulator as a result of mistakes in adjustment, wear of transmission gear and backlashes in connections of details there are random changes in threads length. The purpose of the article is the research of property of random errors of basis giving by STB machine regulator. Mistakes can be both negative, and positive. In case of emergence only negative or only positive mistakes operation of the machine becomes im-possible as there will be a consecutive accumulation of mistakes. As a result of experimental data processing for stable process of weaving and the invariable diameter of basis threads winding of threads it is revealed that the random error of giving is set up as linear function of the accidental length having normal distribution. Measurements of accidental deviations in giving of a basis by the main regulator allowed to construct a curve of normal distribution of its actual length for one pass of weft thread. The presented curve of distribution of random errors in giving of a basis is the displaced curve of normal distribution of the accidental sizes. Also we define the density of probability of normal distribution of basis giving errors connected with a margin er-ror operation of the main regulator knowing of which allows to plan ways of their decrease that is important for improvement of quality of the produced fabrics.

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ACCURACY RATING MEASUREMENT OF VIBRATION ELECTROMECHANICAL DEVICES

Issues of radio electronics ◽

10.21778/2218-5453-2019-7-42-45 ◽

2019 ◽

Vol 1 (7) ◽

pp. 42-45

Author(s):

V. A. Golubkov ◽

V. F. Shishlakov ◽

A. G. Fedorenko ◽

E. Yu. Vataeva

Keyword(s):

Technical Condition ◽

Rotor System ◽

Vibration Measurement ◽

Random Errors ◽

Mass Ratio ◽

Signal Flow Graph ◽

Bond Graphs ◽

Rotor Systems ◽

Electromechanical Devices ◽

Main Components

Electromechanical devices consist mainly of rotor systems. Vibration is the result of the interaction of the elements of the rotor system and is largely determined by the accuracy of manufacturing elements at the production stage and defects arising in the process of operation. The main components of the rotor systems that affect vibration are bearings. To determine the technical condition of the bearings and the service life of the rotor system, it is necessary to accurately measure the unobservable vibrations of the rotor. The article describes the model of the channel for measuring the vibration of an electromechanical system, built using the apparatus of bond graphs. The transfer function is obtained by analyzing the signal flow graph. The systematic and random errors of vibration measurement are analyzed depending on the mass ratio between the system case and the vibration transducer for various sensor masses and attachment rigidity.

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Duloxetine versus ‘active’ placebo, placebo or no intervention for major depressive disorder; a protocol for a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis

Systematic Reviews ◽

10.1186/s13643-021-01722-5 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Faiza Siddiqui ◽

Marija Barbateskovic ◽

Sophie Juul ◽

Kiran Kumar Katakam ◽

Klaus Munkholm ◽

...

Keyword(s):

Quality Of Life ◽

Systematic Review ◽

Sequential Analysis ◽

Citation Index ◽

Trial Sequential Analysis ◽

Random Errors ◽

Major Depressive ◽

Serious Adverse Events ◽

Meta Analyses

Abstract Background Major depression significantly impairs quality of life, increases the risk of suicide, and poses tremendous economic burden on individuals and societies. Duloxetine, a serotonin norepinephrine reuptake inhibitor, is a widely prescribed antidepressant. The effects of duloxetine have, however, not been sufficiently assessed in earlier systematic reviews and meta-analyses. Methods/design A systematic review will be performed including randomised clinical trials comparing duloxetine with ‘active’ placebo, placebo or no intervention for adults with major depressive disorder. Bias domains will be assessed, an eight-step procedure will be used to assess if the thresholds for clinical significance are crossed. We will conduct meta-analyses. Trial sequential analysis will be conducted to control random errors, and the certainty of the evidence will be assessed using GRADE. To identify relevant trials, we will search Cochrane Central Register of Controlled Trials, Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, PsycINFO, Science Citation Index Expanded, Social Sciences Citation Index, Conference Proceedings Citation Index—Science and Conference Proceedings Citation Index—Social Science & Humanities. We will also search Chinese databases and Google Scholar. We will search all databases from their inception to the present. Two review authors will independently extract data and perform risk of bias assessment. Primary outcomes will be the difference in mean depression scores on Hamilton Depression Rating Scale between the intervention and control groups and serious adverse events. Secondary outcomes will be suicide, suicide-attempts, suicidal ideation, quality of life and non-serious adverse events. Discussion No former systematic review has systematically assessed the beneficial and harmful effects of duloxetine taking into account both the risks of random errors and the risks of systematic errors. Our review will help clinicians weigh the benefits of prescribing duloxetine against its adverse effects and make informed decisions. Systematic review registration PROSPERO 2016 CRD42016053931

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Sensing, Actuation, and Control of the SmartX Prototype Morphing Wing in the Wind Tunnel

Actuators ◽

10.3390/act10060107 ◽

2021 ◽

Vol 10 (6) ◽

pp. 107

Author(s):

Nakash Nazeer ◽

Xuerui Wang ◽

Roger M. Groves

Keyword(s):

Wind Tunnel ◽

Optical Fibers ◽

Fiber Optic ◽

Experimental Testing ◽

Single Mode ◽

Fiber Optic Sensor ◽

Sensor Data ◽

Random Errors ◽

Morphing Wing ◽

Actuator Dynamics

This paper presents a study on trailing edge deflection estimation for the SmartX camber morphing wing demonstrator. This demonstrator integrates the technologies of smart sensing, smart actuation and smart controls using a six module distributed morphing concept. The morphing sequence is brought about by two actuators present at both ends of each of the morphing modules. The deflection estimation is carried out by interrogating optical fibers that are bonded on to the wing’s inner surface. A novel application is demonstrated using this method that utilizes the least amount of sensors for load monitoring purposes. The fiber optic sensor data is used to measure the deflections of the modules in the wind tunnel using a multi-modal fiber optic sensing approach and is compared to the deflections estimated by the actuators. Each module is probed by single-mode optical fibers that contain just four grating sensors and consider both bending and torsional deformations. The fiber optic method in this work combines the principles of hybrid interferometry and FBG spectral sensing. The analysis involves an initial calibration procedure outside the wind tunnel followed by experimental testing in the wind tunnel. This method is shown to experimentally achieve an accuracy of 2.8 mm deflection with an error of 9%. The error sources, including actuator dynamics, random errors, and nonlinear mechanical backlash, are identified and discussed.

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Impact of Carbohydrate Counting Error on Glycemic Control in Open-Loop Management of Type 1 Diabetes: Quantitative Assessment Through an in silico Trial

Journal of Diabetes Science and Technology ◽

10.1177/19322968211012392 ◽

2021 ◽

pp. 193229682110123

Author(s):

Chiara Roversi ◽

Martina Vettoretti ◽

Simone Del Favero ◽

Andrea Facchinetti ◽

Pratik Choudhary ◽

...

Keyword(s):

Type 1 Diabetes ◽

Glycemic Control ◽

In Silico ◽

Open Loop ◽

Random Errors ◽

Linear Regression Models ◽

Reference Case ◽

Counting Error ◽

The Impact

Background: In the management of type 1 diabetes (T1D), systematic and random errors in carb-counting can have an adverse effect on glycemic control. In this study, we performed an in silico trial aiming at quantifying the impact of different levels of carb-counting error on glycemic control. Methods: The T1D patient decision simulator was used to simulate 7-day glycemic profiles of 100 adults using open-loop therapy. The simulation was repeated for different values of systematic and random carb-counting errors, generated with Gaussian distribution varying the error mean from -10% to +10% and standard deviation (SD) from 0% to 50%. The effect of the error was evaluated by computing the difference of time inside (∆TIR), above (∆TAR) and below (∆TBR) the target glycemic range (70-180mg/dl) compared to the reference case, that is, absence of error. Finally, 3 linear regression models were developed to mathematically describe how error mean and SD variations result in ∆TIR, ∆TAR, and ∆TBR changes. Results: Random errors globally deteriorate the glycemic control; systematic underestimations lead to, on average, up to 5.2% more TAR than the reference case, while systematic overestimation results in up to 0.8% more TBR. The different time in range metrics were linearly related with error mean and SD ( R2>0.95), with slopes of [Formula: see text], [Formula: see text] for ∆TIR, [Formula: see text], [Formula: see text] for ∆TAR, and [Formula: see text], [Formula: see text] for ∆TBR. Conclusions: The quantification of carb-counting error impact performed in this work may be useful understanding causes of glycemic variability and the impact of possible therapy adjustments or behavior changes in different glucose metrics.

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Methods for estimating uncertainty in factor analytic solutions

Atmospheric Measurement Techniques ◽

10.5194/amt-7-781-2014 ◽

2014 ◽

Vol 7 (3) ◽

pp. 781-797 ◽

Cited By ~ 174

Author(s):

P. Paatero ◽

S. Eberly ◽

S. G. Brown ◽

G. A. Norris

Keyword(s):

Environmental Protection Agency ◽

Synthetic Data ◽

Analytic Solutions ◽

Data Sets ◽

Random Errors ◽

Data Set ◽

Factor Analytic ◽

Uncertainty Estimates ◽

Multilinear Engine ◽

Analytic Models

Abstract. The EPA PMF (Environmental Protection Agency positive matrix factorization) version 5.0 and the underlying multilinear engine-executable ME-2 contain three methods for estimating uncertainty in factor analytic models: classical bootstrap (BS), displacement of factor elements (DISP), and bootstrap enhanced by displacement of factor elements (BS-DISP). The goal of these methods is to capture the uncertainty of PMF analyses due to random errors and rotational ambiguity. It is shown that the three methods complement each other: depending on characteristics of the data set, one method may provide better results than the other two. Results are presented using synthetic data sets, including interpretation of diagnostics, and recommendations are given for parameters to report when documenting uncertainty estimates from EPA PMF or ME-2 applications.

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Combining Multiple Organizational-level Databases: An Empirical Evaluation of Different Matching Methods

Sociological Methods & Research ◽

10.1177/0049124120986184 ◽

2021 ◽

pp. 004912412098618

Author(s):

Tim de Leeuw ◽

Steffen Keijl

Keyword(s):

Empirical Evaluation ◽

Organizational Level ◽

Random Errors ◽

Data Set ◽

Future Studies ◽

Matching Methods ◽

Matching Process ◽

Significant Relationships ◽

Research Findings ◽

Insight Into

Although multiple organizational-level databases are frequently combined into one data set, there is no overview of the matching methods (MMs) that are utilized because the vast majority of studies does not report how this was done. Furthermore, it is unclear what the differences are between the utilized methods, and it is unclear whether research findings might be influenced by the utilized method. This article describes four commonly used methods for matching databases and potential issues. An empirical comparison of those methods used to combine regularly used organizational-level databases reveals large differences in the number of observations obtained. Furthermore, empirical analyses of these different methods reveal that several of them produce both systematic and random errors. These errors can result in erroneous estimations of regression coefficients in terms of direction and/or size as well as an issue where truly significant relationships might be found to be insignificant. This shows that research findings can be influenced by the MM used, which would argue in favor of the establishment of a preferred method as well as more transparency on the utilized method in future studies. This article provides insight into the matching process and methods, suggests a preferred method, and should aid researchers, reviewers, and editors with both combining multiple databases and describing and assessing them.

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Random errors in protein synthesis activate an age-dependent program of muscle atrophy in mice

Communications Biology ◽

10.1038/s42003-021-02204-z ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

James Moore ◽

Rashid Akbergenov ◽

Martina Nigri ◽

Patricia Isnard-Petit ◽

Amandine Grimm ◽

...

Keyword(s):

Protein Synthesis ◽

Muscle Atrophy ◽

Strength Analysis ◽

Dependent Manner ◽

Random Errors ◽

Age Related ◽

Related Phenotype ◽

Age Dependent ◽

Translation Accuracy ◽

Transcriptomic Changes

AbstractRandom errors in protein synthesis are prevalent and ubiquitous, yet their effect on organismal health has remained enigmatic for over five decades. Here, we studied whether mice carrying the ribosomal ambiguity (ram) mutation Rps2-A226Y, recently shown to increase the inborn error rate of mammalian translation, if at all viable, present any specific, possibly aging-related, phenotype. We introduced Rps2-A226Y using a Cre/loxP strategy. Resulting transgenic mice were mosaic and showed a muscle-related phenotype with reduced grip strength. Analysis of gene expression in skeletal muscle using RNA-Seq revealed transcriptomic changes occurring in an age-dependent manner, involving an interplay of PGC1α, FOXO3, mTOR, and glucocorticoids as key signaling pathways, and finally resulting in activation of a muscle atrophy program. Our results highlight the relevance of translation accuracy, and show how disturbances thereof may contribute to age-related pathologies.

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