scholarly journals Statistical Tests for Extreme Precipitation Volumes

Mathematics ◽  
2019 ◽  
Vol 7 (7) ◽  
pp. 648 ◽  
Author(s):  
Victor Korolev ◽  
Andrey Gorshenin ◽  
Konstatin Belyaev
Keyword(s):  
Extreme Precipitation ◽  
Negative Binomial ◽  
Daily Precipitation ◽  
Statistical Tests ◽  
Real Data ◽  
Total Precipitation ◽  
The Novel ◽  
The Real ◽  
Precipitation Volume

The analysis of the real observations of precipitation based on the novel statistical approach using the negative binomial distribution as a model for describing the random duration of a wet period is considered and discussed. The study shows that this distribution fits very well to the real observations and generalized standard methods used in meteorology to detect an extreme volume of precipitation. It also provides a theoretical base for the determination of asymptotic approximations to the distributions of the maximum daily precipitation volume within a wet period, as well as the total precipitation volume over a wet period. The paper demonstrates that the relation of the unique precipitation volume, having the gamma distribution, divided by the total precipitation volume taken over the wet period is given by the Snedecor–Fisher or beta distributions. It allows us to construct statistical tests to determine the extreme precipitations. Within this approach, it is possible to introduce the notions of relatively and absolutely extreme precipitation volumes. An alternative method to determine an extreme daily precipitation volume based on a certain quantile of the tempered Snedecor–Fisher distribution is also suggested. The results of the application of these methods to real data are presented.

scholarly journals Probability Models and Statistical Tests for Extreme Precipitation Based on Generalized Negative Binomial Distributions

Mathematics ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 604 ◽  
Author(s):  
Victor Korolev ◽  
Andrey Gorshenin
Keyword(s):  
Negative Binomial ◽  
Daily Precipitation ◽  
Global Climate ◽  
Statistical Tests ◽  
Real Data ◽  
Total Precipitation ◽  
Climate Trends ◽  
Probability Models ◽  
Precipitation Volume ◽  
Precipitation Total

Mathematical models are proposed for statistical regularities of maximum daily precipitation within a wet period and total precipitation volume per wet period. The proposed models are based on the generalized negative binomial (GNB) distribution of the duration of a wet period. The GNB distribution is a mixed Poisson distribution, the mixing distribution being generalized gamma (GG). The GNB distribution demonstrates excellent fit with real data of durations of wet periods measured in days. By means of limit theorems for statistics constructed from samples with random sizes having the GNB distribution, asymptotic approximations are proposed for the distributions of maximum daily precipitation volume within a wet period and total precipitation volume for a wet period. It is shown that the exponent power parameter in the mixing GG distribution matches slow global climate trends. The bounds for the accuracy of the proposed approximations are presented. Several tests for daily precipitation, total precipitation volume and precipitation intensities to be abnormally extremal are proposed and compared to the traditional PoT-method. The results of the application of this test to real data are presented.

scholarly journals RELATION BETWEEN EXTENSIVE EXTREME PRECIPITATION IN POLAND AND ATMOSPHERIC CIRCULATION

2014 ◽  
Vol 33 (1) ◽  
pp. 115-129 ◽  
Author(s):  
Jakub Nowosad ◽  
Alfred Stach
Keyword(s):  
Seasonal Variation ◽  
Atmospheric Circulation ◽  
Coefficient Of Variation ◽  
Extreme Precipitation ◽  
Daily Precipitation ◽  
Precipitation Data ◽  
Precipitation Volume ◽  
Spatial Features ◽  
The Mean

Abstract The basic aim of this study was to find relations between the dates of occurrence and characteristics of extensive extreme daily (24-h) precipitation totals (EEDPTs) and pressure systems. The analysis was conducted on the basis of precipitation data from the multi-year period 1956-1980 and the Grosswetterlagen classification of circulation situations. EEDPTs were taken to embrace those cases of maximum annual daily precipitation totals that were registered on the same day at a minimum of 75 precipitation stations. In the years 1956-1980 there were 209 such events. The hypothesis about the effect of a circulation situation on the probability of occurrence of an EEDPT was verified in quantitative terms, the reference being both the entire multi-year period and the seasonal variation in the occurrence of precipitation of this type. Next, circulation situations were compared in terms of amount-related parameters of EEDPTs (mean precipitation, coefficient of variation), their spatial features (perimeter, area), and precipitation volume. The analyses performed show a statistically significant dependence between the atmospheric circulation and extensive extreme precipitation. It was demonstrated that there were circulation situations during which EEDPTs occurred much more often or much more rarely than over the entire multi-year period under study. Also identified was the connection of an atmospheric circulation with the mean amount, coefficient of variation and volume of extensive extreme precipitation.

scholarly journals Extreme Precipitation Changes in the Semiarid Region of Xinjiang, Northwest China

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Yanwei Zhang ◽  
Quansheng Ge ◽  
Minzhe Liu
Keyword(s):  
Extreme Precipitation ◽  
Daily Precipitation ◽  
Statistical Tests ◽  
Northwest China ◽  
Semiarid Region ◽  
Extreme Precipitation Events ◽  
Precipitation Records ◽  
Precipitation Changes ◽  
Climate Disasters ◽  
Precipitation Events

This study focuses on extreme precipitation changes in Xinjiang Province of Northwest China, which has experienced an increase in climate disasters in recent years. This paper investigates extreme precipitation events in Xinjiang, using 54 stations with daily precipitation records from the period 1961–2008. Different statistical tests and approaches were used to check the significance of trends of single and Xinjiang regionally aggregated precipitation series for intensity and in frequency. There were predominantly positive trends in annual maximum precipitation and a remarkable increment in the frequency of extreme precipitation over certain thresholds (from 10 to 40 mm). Although the series of frequencies exceeding thresholds had positive trends, only a minority were statistically significant. This lack of significance is because of the high variability of extreme precipitation in space and time. Thus, significant trends were evident when we assessed the extreme precipitation indicators of intensity and frequency at the regional level, both in intensity and frequency over thresholds, with a clearer signal in Xinjiang.

scholarly journals The image of a teenage girl in Chuck Palahniuk’s novel “Cursed”

Litera ◽  
2020 ◽  
pp. 28-43
Author(s):  
Inna Aleksandrovna Kurakova
Keyword(s):  
Future Development ◽  
Real World ◽  
Literary Analysis ◽  
The Novel ◽  
Teenage Girl ◽  
Dual Nature ◽  
The Real ◽  
Chuck Palahniuk ◽  
Inner World

The goal of this research is determination of specificity of the image of the heroine in the novel by a contemporary American writer Chuck Palahniuk “Cursed”. The article analyzes such aspects as the inner world of the character, relationship with parents, agemates and society in the two contrasting words: real world, during the lifetime of the heroine, and surreal, in hell, after her death. Detailed description of the character allows seeing two different guises of the heroine, while application of literary analysis allows analyzing the traits of the protagonist and place within the system of artistic world of Chuck Palahniuk’s prose. The paper presents a review of scientific pursuits of the Russian and foreign scholars dealing with the works of Chuck Palahniuk. The novelty of this research consists in determination of dual nature of the image of a teenager reflected in the two-world realm created by C. Palahniuk. The analysis demonstrated that in to contrasting worlds, the image of a teenager transforms and manifests differently. In the real world, it is a modest girl, with multiple feelings of inferiority, who has complicated relationships with parents and surrounding people. In the surreal world, she attains new traits, such as authoritativeness, courage, ability to maintain friendships. The conclusion is made that that Chuck Palahniuk creates two images of the heroine. Paradox lies in the fact that an unsuccessful individual in a real world becomes successful in the afterlife. Practical value of this article is defined by its contribution into the theory of literary image, particularly, future development of the methodology for studying the image of the character in transgressive prose.

scholarly journals An Alternative Index for the Contribution of Precipitation on Very Wet Days to the Total Precipitation

2014 ◽  
Vol 27 (4) ◽  
pp. 1365-1378 ◽  
Author(s):  
R. Leander ◽  
T. A. Buishand ◽  
A. M. G. Klein Tank
Keyword(s):  
Weibull Distribution ◽  
Extreme Precipitation ◽  
Daily Precipitation ◽  
Northern Europe ◽  
Precipitation Series ◽  
Total Precipitation ◽  
Southern Europe ◽  
Monthly Basis ◽  
Alternative Index ◽  
The Mean

Abstract Daily precipitation series from more than 1800 stations across Europe are analyzed for the fraction of the total precipitation due to very wet days: that is, days with precipitation amounts exceeding the 95th percentile. This fraction is calculated on a seasonal (3-monthly) basis for the period 1961–2010. A new index S95pTOT is introduced as an alternative to the frequently used index R95pTOT. Contrary to R95pTOT, which uses a fixed climatological 95th percentile, the new index assumes a separate 95th percentile for each year. Based on a Weibull distribution fit to the wet-day precipitation amounts, an analytical expression for S95pTOT is derived. It is shown that R95pTOT is strongly influenced by changes in the mean wet-day precipitation, whereas S95pTOT is more representative of changes in the distributional shape. The results for S95pTOT do not support the conclusion for a disproportional increase of extreme precipitation over northern Europe as was concluded from the trend in R95pTOT in earlier studies. Also, the contrast between trends in northern and southern Europe in winter is less pronounced for S95pTOT than for R95pTOT.

A novel method for the determination of linting propensity of paper

TAPPI Journal ◽  
2012 ◽  
Vol 11 (10) ◽  
pp. 9-17
Author(s):  
ALESSANDRA GERLI ◽  
LEENDERT C. EIGENBROOD
Keyword(s):  
Ash Content ◽  
The Novel ◽  
Offset Printing ◽  
Excellent Correlation ◽  
End Conditions ◽  
Bottom Side ◽  
Novel Method ◽  
Total Fraction

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.

Method of determination of the text direction on the image with the use of convolutional neural network

2020 ◽  
pp. 96-99
Author(s):  
P.L. Nikolaev
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Deep Neural Network ◽  
Binary Classification ◽  
Synthetic Data ◽  
Real Data ◽  
Method Of Determination ◽  
Classification Of Images

This article deals with method of binary classification of images with small text on them Classification is based on the fact that the text can have 2 directions – it can be positioned horizontally and read from left to right or it can be turned 180 degrees so the image must be rotated to read the sign. This type of text can be found on the covers of a variety of books, so in case of recognizing the covers, it is necessary first to determine the direction of the text before we will directly recognize it. The article suggests the development of a deep neural network for determination of the text position in the context of book covers recognizing. The results of training and testing of a convolutional neural network on synthetic data as well as the examples of the network functioning on the real data are presented.

Single Depth View Based Real-Time Reconstruction of Hand-Object Interactions

2021 ◽  
Vol 40 (3) ◽  
pp. 1-12
Author(s):  
Hao Zhang ◽  
Yuxiao Zhou ◽  
Yifei Tian ◽  
Jun-Hai Yong ◽  
Feng Xu
Keyword(s):  
Real Time ◽  
Synthetic Data ◽  
Real Data ◽  
Depth Image ◽  
Real Time System ◽  
The Real ◽  
Time Performance ◽  
Contact Constraint ◽  
Object Shapes ◽  
Object Interactions

Reconstructing hand-object interactions is a challenging task due to strong occlusions and complex motions. This article proposes a real-time system that uses a single depth stream to simultaneously reconstruct hand poses, object shape, and rigid/non-rigid motions. To achieve this, we first train a joint learning network to segment the hand and object in a depth image, and to predict the 3D keypoints of the hand. With most layers shared by the two tasks, computation cost is saved for the real-time performance. A hybrid dataset is constructed here to train the network with real data (to learn real-world distributions) and synthetic data (to cover variations of objects, motions, and viewpoints). Next, the depth of the two targets and the keypoints are used in a uniform optimization to reconstruct the interacting motions. Benefitting from a novel tangential contact constraint, the system not only solves the remaining ambiguities but also keeps the real-time performance. Experiments show that our system handles different hand and object shapes, various interactive motions, and moving cameras.

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