Basic Statistical Properties of the Knot Efficiency

A knot is the weakest point of every rope, and the <i>knot efficiency</i> measures the portion of original rope strength taken away by the knot. Despite possible safety implications, surprisingly little attention has been paid to this life-critical quantity in research papers. Knot effic...

Full description

Bibliographic Details
Main Authors: Ján Šimon, Branislav Ftorek
Format: Article
Language:English
Published: MDPI AG 2022-09-01
Series:Symmetry
Subjects:
Online Access:https://www.mdpi.com/2073-8994/14/9/1926
_version_ 1797481874696699904
author Ján Šimon
Branislav Ftorek
author_facet Ján Šimon
Branislav Ftorek
author_sort Ján Šimon
collection DOAJ
description A knot is the weakest point of every rope, and the <i>knot efficiency</i> measures the portion of original rope strength taken away by the knot. Despite possible safety implications, surprisingly little attention has been paid to this life-critical quantity in research papers. Knot efficiency is directly immeasurable and the only way to obtain it is by calculation from rope breaking strength. However, this complication makes room for a wide spectrum of misleading concepts. The vast majority of authors do not treat knot efficiency as a random variable, and published results mostly suffer from incorrect statistical processing. The main goal of the presented paper is to fix this issue by proposing correct statistical tools needed for knot efficiency assessment. The probability density function of knot efficiency <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>ψ</mi><mo>(</mo><mi>η</mi><mo>)</mo></mrow></semantics></math></inline-formula> has been derived in general, as well as for normally distributed breaking strength. Statistical properties of knot efficiency PDF have been discussed, and a less complex approximation of knot efficiency PDF has been proposed and investigated.
first_indexed 2024-03-09T22:20:48Z
format Article
id doaj.art-09e374f5fb36421480b11965375c7e4d
institution Directory Open Access Journal
issn 2073-8994
language English
last_indexed 2024-03-09T22:20:48Z
publishDate 2022-09-01
publisher MDPI AG
record_format Article
series Symmetry
spelling doaj.art-09e374f5fb36421480b11965375c7e4d2023-11-23T19:13:21ZengMDPI AGSymmetry2073-89942022-09-01149192610.3390/sym14091926Basic Statistical Properties of the Knot EfficiencyJán Šimon0Branislav Ftorek1Faculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, SlovakiaFaculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, SlovakiaA knot is the weakest point of every rope, and the <i>knot efficiency</i> measures the portion of original rope strength taken away by the knot. Despite possible safety implications, surprisingly little attention has been paid to this life-critical quantity in research papers. Knot efficiency is directly immeasurable and the only way to obtain it is by calculation from rope breaking strength. However, this complication makes room for a wide spectrum of misleading concepts. The vast majority of authors do not treat knot efficiency as a random variable, and published results mostly suffer from incorrect statistical processing. The main goal of the presented paper is to fix this issue by proposing correct statistical tools needed for knot efficiency assessment. The probability density function of knot efficiency <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>ψ</mi><mo>(</mo><mi>η</mi><mo>)</mo></mrow></semantics></math></inline-formula> has been derived in general, as well as for normally distributed breaking strength. Statistical properties of knot efficiency PDF have been discussed, and a less complex approximation of knot efficiency PDF has been proposed and investigated.https://www.mdpi.com/2073-8994/14/9/1926knot efficiencyprobability density functioncumulative distribution functionstatistical properties
spellingShingle Ján Šimon
Branislav Ftorek
Basic Statistical Properties of the Knot Efficiency
Symmetry
knot efficiency
probability density function
cumulative distribution function
statistical properties
title Basic Statistical Properties of the Knot Efficiency
title_full Basic Statistical Properties of the Knot Efficiency
title_fullStr Basic Statistical Properties of the Knot Efficiency
title_full_unstemmed Basic Statistical Properties of the Knot Efficiency
title_short Basic Statistical Properties of the Knot Efficiency
title_sort basic statistical properties of the knot efficiency
topic knot efficiency
probability density function
cumulative distribution function
statistical properties
url https://www.mdpi.com/2073-8994/14/9/1926
work_keys_str_mv AT jansimon basicstatisticalpropertiesoftheknotefficiency
AT branislavftorek basicstatisticalpropertiesoftheknotefficiency