scholarly journals Categorization of Floods in the Opava River Basine

Geografie ◽  
2015 ◽  
Vol 120 (1) ◽  
pp. 84-100
Author(s):  
Jana Šmídová
Keyword(s):  
Cluster Analysis ◽  
Statistical Methods ◽  
River Basin ◽  
Time Distribution ◽  
Similarity Index ◽  
Common Features ◽  
Flood Regime ◽  
Index Flood ◽  
The Individual ◽  
Flood Waves

The paper summarizes our knowledge of the flood regime of the Opava river basin between 1960 and 2010. Emphasis is placed on the categorization of the individual components of the causes of flooding and the development of floods. Analogies were sought among floods based on their causal symptoms and the characteristics of the runoff response. Summer and winter categories of flood waves have been delineated via statistical methods, which characterize common features of floods by cluster analysis and similarity index. Flood episodes have been divided into nine groups (four types of winter- and five types of summer floods) based on the spatial and time distribution of rainfall, which is caused by specific atmospheric circulation and thus influences the development and formation of the flow waves.

Rainfall Time Distribution over the Wuliangsuhai Eastern River Basin

2014 ◽  
Vol 955-959 ◽  
pp. 1143-1146
Author(s):  
Yu Jin Zhang ◽  
Rui Hong Yu ◽  
Yun Hao ◽  
Huan Yang
Keyword(s):  
Statistical Methods ◽  
River Basin ◽  
Average Method ◽  
Time Distribution ◽  
Moving Average ◽  
Rate Of Change ◽  
Rainfall Data ◽  
Downward Trend

The 25 years of rainfall data in Wuliangsuhai eastern river basin from 1986 to 2010 are summarized and analyzed based on two statistical methods. The two statistical methods named moving average method and Cumulative Departure Curve are applied to make a conclusion that the rainfall in 25 years has a downward trend and the rate of change become high in new century.

scholarly journals Assessing the Pollution Level in the Kuban River Basin by Multivariate Cluster Analysis

2020 ◽  
Vol 17 (4) ◽  
pp. 73-80 ◽  
Author(s):  
Vera Snezhko ◽  
Dmitrii Benin ◽  
Artem Lukyanets ◽  
Larisa Kondratenko
Keyword(s):  
Cluster Analysis ◽  
River Basin ◽  
Ecological Status ◽  
Chemical System ◽  
Pollution Level ◽  
Multivariate Cluster Analysis ◽  
Water Chemical Composition ◽  
Aluminium Copper ◽  
Kuban River ◽  
Multivariate Cluster

Considering features of hydrological conditions for hydro-chemical system, this paper analyses the performance of the hydro-ecological status of the Kuban river basin.. The results of the study on water chemical composition depending on the distance from the source are presented. By comparing the results with the reference values of water quality, increased aluminium, zinc, and copper content was established. Respective dendrograms of hydro-ecological studies obtained according to performed analysis for the Kuban River and its tributaries are presented. The relevance of the findings received is p<0.0005 and the correlation coefficient corresponds to 0.935...1. The results of multivariate cluster analysis showed that the Kuban basin has an increased content of particular heavy metals such as aluminium, copper, and zinc.

scholarly journals Fully Data-Driven Pseudohealthy Synthesis for Planning Valve-Sparing Aortic Root Reconstruction using Conditional Variational Autoencoders

2020 ◽  
Vol 6 (3) ◽  
pp. 284-287
Author(s):  
Jannis Hagenah ◽  
Mohamad Mehdi ◽  
Floris Ernst
Keyword(s):  
Aortic Root ◽  
Similarity Index ◽  
Ground Truth ◽  
Representation Learning ◽  
Patient Specific ◽  
Ultrasound Images ◽  
Specific Geometry ◽  
The Individual ◽  
Native Root ◽  
Original Information

AbstractAortic root aneurysm is treated by replacing the dilated root by a grafted prosthesis which mimics the native root morphology of the individual patient. The challenge in predicting the optimal prosthesis size rises from the highly patient-specific geometry as well as the absence of the original information on the healthy root. Therefore, the estimation is only possible based on the available pathological data. In this paper, we show that representation learning with Conditional Variational Autoencoders is capable of turning the distorted geometry of the aortic root into smoother shapes while the information on the individual anatomy is preserved. We evaluated this method using ultrasound images of the porcine aortic root alongside their labels. The observed results show highly realistic resemblance in shape and size to the ground truth images. Furthermore, the similarity index has noticeably improved compared to the pathological images. This provides a promising technique in planning individual aortic root replacement.

Missing Data in Research on Youth and Family Programs

2021 ◽  
pp. 003329412110268
Author(s):  
Jaime Ballard ◽  
Adeya Richmond ◽  
Suzanne van den Hoogenhof ◽  
Lynne Borden ◽  
Daniel Francis Perkins
Keyword(s):  
Missing Data ◽  
Statistical Methods ◽  
Self Report ◽  
Program Participation ◽  
Multilevel Data ◽  
Individual Level ◽  
Level Data ◽  
Before And After ◽  
Post Test ◽  
The Individual

Background Multilevel data can be missing at the individual level or at a nested level, such as family, classroom, or program site. Increased knowledge of higher-level missing data is necessary to develop evaluation design and statistical methods to address it. Methods Participants included 9,514 individuals participating in 47 youth and family programs nationwide who completed multiple self-report measures before and after program participation. Data were marked as missing or not missing at the item, scale, and wave levels for both individuals and program sites. Results Site-level missing data represented a substantial portion of missing data, ranging from 0–46% of missing data at pre-test and 35–71% of missing data at post-test. Youth were the most likely to be missing data, although site-level data did not differ by the age of participants served. In this dataset youth had the most surveys to complete, so their missing data could be due to survey fatigue. Conclusions Much of the missing data for individuals can be explained by the site not administering those questions or scales. These results suggest a need for statistical methods that account for site-level missing data, and for research design methods to reduce the prevalence of site-level missing data or reduce its impact. Researchers can generate buy-in with sites during the community collaboration stage, assessing problematic items for revision or removal and need for ongoing site support, particularly at post-test. We recommend that researchers conducting multilevel data report the amount and mechanism of missing data at each level.

Abiding by the Law? Using Benford’s Law to Examine the Accuracy of Nonprofit Financial Reports

2019 ◽  
Vol 49 (3) ◽  
pp. 548-570 ◽  
Author(s):  
Heng Qu ◽  
Richard Steinberg ◽  
Ronelle Burger
Keyword(s):  
Statistical Methods ◽  
Organizational Level ◽  
Benford’S Law ◽  
Financial Reports ◽  
Forensic Accounting ◽  
Data Form ◽  
Benford's Law ◽  
Natural Data ◽  
The Individual ◽  
Academic Study

Benford’s Law asserts that the leading digit 1 appears more frequently than 9 in natural data. It has been widely used in forensic accounting and auditing to detect potential fraud, but its application to nonprofit data is limited. As the first academic study that applies Benford’s Law to U.S. nonprofit data (Form 990), we assess its usefulness in prioritizing suspicious filings for further investigation. We find close conformity with Benford’s Law for the whole sample, but at the individual organizational level, 34% of the organizations do not conform. Deviations from Benford’s law are smaller for organizations that are more professional, that report positive fundraising and administration expenses, and that face stronger funder oversight. We suggest improved statistical methods and experiment with a new measure of the extent of deviation from Benford’s Law that has promise as a more discriminating screening metric.

scholarly journals Reproductive biology of Rhaphiodon vulpinus (Ostariophysi: Cynodontidae) in the Tocantins River Basin, Brazil

2007 ◽  
Vol 5 (4) ◽  
pp. 479-484 ◽  
Author(s):  
Andréa L. Neuberger ◽  
Elineide E. Marques ◽  
Carlos S. Agostinho ◽  
Rafael J. de Oliveira
Keyword(s):  
River Basin ◽  
Reproductive Biology ◽  
Mean Value ◽  
Reproductive Period ◽  
Total Weight ◽  
Individual Female ◽  
Relative Fecundity ◽  
Mean Diameter ◽  
Tocantins River ◽  
The Individual

In order to evaluate aspects of the reproductive biology of Rhaphiodon vulpinus in the Upper and Middle Tocantins River, samples were taken monthly from October, 1999 through September, 2001, by means of gill nets. Males, which were more abundant than females (chi2 146.87: df=1: p<0.05), matured at a smaller size. The reproductive period of the species extended essentially from November through January, with a peak of activity in November. Fecundity, with an estimated mean value of 98,185 oocytes, varied from 38,177 to 215,841 oocytes, and it did not correlate with the length of the individual female analyzed (r=0.4663: p=0.206). Relative fecundity was 130.6 oocytes/g total weight. Mature oocytes had a mean diameter of 0.98 mm, corresponding to a volume of 0.50 mm³.

scholarly journals Farms Typologies and Their Impact on the Development of Rural Areas in Moldova

2018 ◽  
Vol 1 (1) ◽  
pp. 190-195
Author(s):  
Liliana Cimpoies ◽  
Elena Semionova
Keyword(s):  
Cluster Analysis ◽  
Rural Areas ◽  
Agricultural Production ◽  
Rural Economy ◽  
Family Farms ◽  
Market Place ◽  
Sustainable Rural Development ◽  
Different Types ◽  
The Individual ◽  
Academy Of Sciences

Abstract For Moldova’s agriculture are characterized the existence of many small family farms and only a small number of corporate holdings (limited liabilities companies, agricultural production cooperatives etc). Most of individual farms, small by size produce only for own family consumption and cannot find their way to the market place. The accentuated poverty makes rural economy to flow more and more to a natural subsistence economy, isolating itself from the market economy. The goal of this paper is to delimitate different types of farms based on selected indicators and to appreciate their level of development. Differences in farms levels of development are appreciated through cluster analysis. The research includes the analysis of farms survey data. This research was carried as a part of the Academy of Sciences project “Sustainable rural development in Republic of Moldova in the context of EU accession”. In the project were surveyed 938 individual farms from nine districts across the country. As a result, we distinguish three types of farms: natural, family and market household. The cluster analysis allows to characterize the farms level development, to determine the main priority directions, and to elaborate measures for the individual farms further sustainable development.

scholarly journals Psychophysiological features of fighters of different tactical styles of conducting competitive duels

2019 ◽  
Vol 5 (3) ◽  
pp. 63
Author(s):  
G.O. Ogar ◽  
E.I. Lewandowski
Keyword(s):  
Cluster Analysis ◽  
Hierarchical Cluster Analysis ◽  
Hierarchical Cluster ◽  
Test Results ◽  
Time Switching ◽  
The Individual ◽  
Switching Attention ◽  
Individual Training

<p><strong>Objective</strong>: To determine the psychophysiological features of skilled freestyle wrestlers with different tactical ways of fighting.</p><p><strong>Materials and Methods</strong>: The study involved 15 freestyle wrestlers who are students of the H.S. Skovoroda Kharkiv National Pedagogical University.  The athletes had experience in free-wrestling from 5 to 7 years, qualification of the  Meister kandidat (n = 6) and the 1st sports category (n = 9), age of the examinees - 17-21 years. With the help of V. Schulte's technique, testing of stability of attention and dynamics of efficiency of fighters was carried out. The indicators of switching and distribution of attention of the investigated by the method of FD were also tested. Humpback. A hierarchical cluster analysis of psychophysiological test results was conducted, according to which the investigated fighters were divided into two groups.</p><p> <strong>Results</strong>: According to the results of testing psychophysiological indicators, some differences were found between the groups. Cluster analysis of testing results of psychophysiological features of freestyle wrestlers divided the studied athletes into two groups. The first group includes fighters who lead competitive duels against defense, using mostly counter-attacks (defensive, counter-attacking style of conducting a competitive duel). The second group of investigated fighters included athletes, who are fighting in an active style (attacking style of running a competitive fight). The wrestlers of the second group, in terms of performance (p &lt;0.001) outperform the athletes of the first group. The first group studied showed a better time switching attention than their opponents (p&lt;0.05).</p><p><strong>Conclusions</strong>: The results of the study can be used in the individual training of fighters to determine the optimal tactical manner of the fight for specific athletes.</p>

scholarly journals Characteristics of multi-annual variation of precipitation in areas particularly exposed to extreme phenomena. Part 1. The upper Vistula river basin

2018 ◽  
Vol 49 ◽  
pp. 00121
Author(s):  
Bernard Twaróg
Keyword(s):  
Cluster Analysis ◽  
Data Analysis ◽  
River Basin ◽  
Spatial Resolution ◽  
Climate Changes ◽  
Annual Variation ◽  
Hydrological Cycle ◽  
Initial Section ◽  
Mean Values ◽  
Vistula River

The study contains an analysis of precipitation, covering multiple profiles and based on the GPCC database that provides monthly mean values for the territory upper Vistula catchment. The analysis includes data for the period 1901-2010 with a spatial resolution of 0.5° × 0.5° of geographic longitude and latitude. The initial section of the analysis contains an assessment of GPCC data accuracy for the territory of Poland and the period 1961-1990. The following sections include a data analysis in monthly profiles and hydrological cycle profiles, taking into account hydrological summer and hydrological winter. A cluster analysis is also included, with drought and flood periods indicated. The periodical nature of precipitation is assessed and the trends in climate changes calculated.

Superimposed non-stationary renewal processes

1971 ◽  
Vol 8 (01) ◽  
pp. 184-192 ◽  
Author(s):  
S. Blumenthal ◽  
J. A. Greenwood ◽  
L. Herbach
Keyword(s):  
Waiting Time ◽  
Time Distribution ◽  
Classical Result ◽  
Scale Parameter ◽  
Renewal Processes ◽  
Stationary Case ◽  
Waiting Time Distribution ◽  
Component Processes ◽  
The Individual

For superposition of independent, stationary renewal processes, it is well known that the distribution of waiting time between events for the superimposed process is approximately exponential if the number of processes involved is sufficiently large, (see Khintchine (1960), Ososkov (1956)). We assume that all component processes have the same age t, and we generalize the classical result to show that even for t finite (non-stationary case), the limiting waiting time distribution (as the number of processes increases) is exponential with a scale parameter which depends on t through the average of the individual process renewal densities.

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