scholarly journals Peculiarity of theoretical distribution law selection by gas-insulated transformers external isolation calculation

2020 ◽  
Vol 3 (1) ◽  
pp. 10-14
Author(s):  
Liudmyla Zhorniak ◽  
Alexej Afanasiev ◽  
Valerii Poliakov ◽  
Zhanna Kulyk ◽  
Roman Kot ◽  
...  
Keyword(s):  
Theoretical Distribution ◽  
Distribution Law

Allocation of the wear of the main support of raba-man cylinders blocks

2020 ◽  
pp. 20-27
Author(s):  
Dar’ya A. Lebedeva ◽  
Vitaliy A. Zuyevskiy ◽  
Il’ya V. Romanov
Keyword(s):  
Statistical Processing ◽  
Integral Function ◽  
Distribution Functions ◽  
Theoretical Distribution ◽  
Research Purpose ◽  
Design Stage ◽  
Distribution Law ◽  
Statistical Series ◽  
Distribution Laws ◽  
Main Support

Wear of the main supports is a defect of many domestic and foreign engines. Statistical processing and selection of the theoretical distribution of the wear greatly simplifies the choice of recovery methods at the design stage. (Research purpose) The research purpose is choosing the theoretical law of wear allocation of the main supports of Raba-MAN cylinder blocks. (Materials and methods) Authors carried out statistical processing of micrometric data of the main supports of Raba-MAN cylinder blocks. Authors measured the diameters of the main supports of 40 cylinder blocks Raba-MAN three times with tightened fastening bolts with NI 100-160 GOST 868-82 micrometer with a step of 0.01 millimeters. Authors evaluated the match of experimental and theoretical distribution laws by Pearson’s criterion. (Results and discussion) The measurements results were summarized in a statistical series. The article presents a histogram of accumulated experimental probabilities and graphs of differential and integral distribution functions. It was found that the probability of matching of experimental and theoretical distribution laws for both laws is less than 10 percent. Article notes that the chosen distribution laws are not characterized by the presence of the second peak on the graph of the differential function, and the slope of the curve of integral function when approaching the last interval is much higher than the theoretical curves functions. (Conclusion) The maximum wear does not exceed 0.16 millimeters. Since the most common laws of normal distribution and Weibull distribution in statistical calculations are unsuitable in this case, additional research is required to select the theoretical distribution law.

Guaranteed values – the basis of the analysis of the quality of individual products

2019 ◽  
pp. 20-33
Author(s):  
D. N. Kalacheva
Keyword(s):  
Frequency Distribution ◽  
Distribution Law ◽  
Basic Characteristics ◽  
Definition Of

Herein, the main features and rules of using guaranteed values when analyzing the quality of rocket - space equipment products are considered. The definition of the guaranteed value and the form of its presentation is given. It is indicated that guaranteed value is distributed and is characterized by the frequency distribution law. The main methods of representation and conversion of guaranteed values are statistical. Examples of determining the basic characteristics of guaranteed values are given.

METHOD FOR ESTIMATING PARAMETERS OF GENERALIZED MODEL OF LUMINOSITY OF SPACE OBJECTS BASED ON DATA FROM DIFFERENT RANGES

2018 ◽  
pp. 57-62
Author(s):  
E. I. Gundrova ◽  
A. P. Lukyanov ◽  
A. V. Pruglo ◽  
S. S. Ravdin
Keyword(s):  
Phase Angle ◽  
Real Data ◽  
Model Data ◽  
Space Object ◽  
Distribution Law ◽  
Generalized Model ◽  
Measurement Results ◽  
Space Objects ◽  
Reference Distance

Previously, the authors have proposed a generalized model for estimating the distribution law parameters of luminosity of space objects, assuming that not only successful but also unsuccessful measurement results are taken into account. Estimation was done on the data of observations under similar conditions: phase angle, range, sensibility of the telescope. The algorithm under such limitations was tested on model data and real measurements. Therefore, obtained results showed that algorithm did not fit for cases of changing range of space objects. In this work, the new algorithm, that allows to merge information from different ranges to the observed space object, is proposed. In this case, luminosity values are reduced to the ones at a reference distance of 1000 km considering sensibility of the telescope. To obtain estimates of the parameters the Cramer-Mises-Smirnov criterion is used. This algorithm was tested on model data and results of its work on real data were obtained. The data showed correct work of the algorithm and also confirmed the practicability of organization the registration of unsuccessful measurements.

scholarly journals Research on road engineering detection method based on GPR technology

2020 ◽  
Vol 165 ◽  
pp. 04014
Author(s):  
Liu Tao ◽  
Li Jia ◽  
Zheng Zhi-gang ◽  
Huang Zhi ◽  
Jiang Jian ◽  
...  
Keyword(s):  
Parameter Setting ◽  
Non Destructive Testing ◽  
Practical Application ◽  
Distribution Law ◽  
Destructive Testing ◽  
Road Engineering ◽  
The Road ◽  
Image Optimization ◽  
Testing Technology ◽  
Non Destructive

GPR is an effective non-destructive testing technology. This paper introduces its composition principle and operation method, explains the process of parameter setting and image optimization, obtains the dielectric constant of 10000 points, compares it with the density, and then obtains the uniformity distribution law of construction quality based on image. By calibrating the thickness of the road surface, the effective detection of road diseases can be realized, and the theoretical basis and practical application conditions of GPR technology can be clarified.

scholarly journals Probability Characteristics, Area Reduction, and Wind Directionality Effects of Extreme Pressure Coefficients of High-Rise Buildings

2021 ◽  
Vol 11 (15) ◽  
pp. 7121
Author(s):  
Shouke Li ◽  
Feipeng Xiao ◽  
Yunfeng Zou ◽  
Shouying Li ◽  
Shucheng Yang ◽  
...  
Keyword(s):  
Probability Distribution ◽  
Pressure Coefficient ◽  
Wind Pressure ◽  
Extreme Pressure ◽  
Distribution Law ◽  
Distribution Fitting ◽  
Pressure Coefficients ◽  
High Rise ◽  
Area Reduction ◽  
The Mean

Wind tunnel tests are carried out for the Commonwealth Advisory Aeronautical Research Council (CAARC) high-rise building with a scale of 1:400 in exposure categories D. The distribution law of extreme pressure coefficients under different conditions is studied. Probability distribution fitting is performed on the measured area-averaged extreme pressure coefficients. The general extreme value (GEV) distribution is preferred for probability distribution fitting of extreme pressure coefficients. From the comparison between the area-averaged coefficients and the value from GB50009-2012, it is indicated that the wind load coefficients from GB50009-2012 may be non-conservative for the CAARC building. The area reduction effect on the extreme wind pressure is smaller than that on the mean wind pressure from the code. The recommended formula of the area reduction factor for the extreme pressure coefficient is proposed in this study. It is found that the mean and the coefficient of variation (COV) for the directionality factors are 0.85 and 0.04, respectively, when the orientation of the building is given. If the uniform distribution is given for the building’s orientation, the mean value of the directionality factors is 0.88, which is close to the directionality factor of 0.90 given in the Chinese specifications.

scholarly journals Statistical Law and Predictive Analysis of Compressive Strength of Cemented Sand and Gravel

2020 ◽  
Vol 27 (1) ◽  
pp. 291-298
Author(s):  
Shoukai Chen ◽  
Yongqiwen Fu ◽  
Lei Guo ◽  
Shifeng Yang ◽  
Yajing Bie
Keyword(s):  
Compressive Strength ◽  
Back Propagation ◽  
Back Propagation Neural Network ◽  
Predictive Analysis ◽  
Distribution Law ◽  
Data Set ◽  
Cemented Sand ◽  
Mix Proportion ◽  
Kolmogorov Smirnov ◽  
Sand And Gravel

AbstractA data set of cemented sand and gravel (CSG) mix proportion and 28-day compressive strength was established, with outliers determined and removed based on the Boxplot. Then, the distribution law of compressive strength of CSG was analyzed using the skewness kurtosis and single-sample Kolmogorov-Smirnov tests. And with the help of Python software, a model based on Back Propagation neural network was built to predict the compressive strength of CSG according to its mix proportion. The results showed that the compressive strength follows the normal distribution law, the expected value and variance were 5.471 MPa and 3.962 MPa respectively, and the average relative error was 7.16%, indicating the predictability of compressive strength of CSG and its correlation with the mix proportion.

Estimates of linkage disequilibrium and the recombination parameter determined from segregating nucleotide sites in the alcohol dehydrogenase region of Drosophila pseudoobscura.

Genetics ◽  
1993 ◽  
Vol 135 (2) ◽  
pp. 541-552 ◽  
Author(s):  
S W Schaeffer ◽  
E L Miller
Keyword(s):  
Linkage Disequilibrium ◽  
Alcohol Dehydrogenase ◽  
Distance Effect ◽  
Theoretical Distribution ◽  
Drosophila Pseudoobscura ◽  
Significant Linkage Disequilibrium ◽  
Effective Population ◽  
Nucleotide Distance ◽  
Significant Linkage ◽  
Recombination Parameter

Abstract The alcohol dehydrogenase (Adh) region of Drosophila pseudoobscura, which includes the two genes Adh and Adh-Dup, was used to examine the pattern and organization of linkage disequilibrium among pairs of segregating nucleotide sites. A collection of 99 strains from the geographic range of D. pseudoobscura were nucleotide-sequenced with polymerase chain reaction-mediated techniques. All pairs of the 359 polymorphic sites in the 3.5-kb Adh region were tested for significant linkage disequilibrium with Fisher's exact test. Of the 74,278 pairwise comparisons of segregating sites, 127 were in significant linkage disequilibrium at the 5% level. The distribution of five linkage disequilibrium estimators D(ij), D2, r(ij), r2 and D(ij) were compared to theoretical distributions. The observed distributions of D(ij), D2, r(ij) and r2 were consistent with the theoretical distribution given an infinite sites model. The observed distribution of D(ij) differed from the theoretical distribution because of an excess of values at -1 and 1. No spatial pattern was observed in the linkage disequilibrium pattern in the Adh region except for two clusters of sites nonrandomly associated in the adult intron and intron 2 of Adh. The magnitude of linkage disequilibrium decreases significantly as nucleotide distance increases, or a distance effect. Adh-Dup had a larger estimate of the recombination parameter, 4Nc, than Adh, where N is the effective population size and c is the recombination rate. A comparison of the mutation and recombination parameters shows that 7-17 recombination events occur for each mutation event. The heterogeneous estimates of the recombination parameter and the inverse relationship between linkage disequilibrium and nucleotide distance are no longer significant when the two clusters of Adh intron sites are excluded from analyses. The most likely explanation for the two clusters of linkage disequilibria is epistatic selection between sites in the cluster to maintain pre-mRNA secondary structure.

Sign in / Sign up

Export Citation Format

Share Document