Assessment of the technical state and the possibility of its control for the further safe operation of building structures of mining facilities

The object of the study is the coefficients of asymmetry and excess of the selective distribution of hazardous parameters of the gas environment during material fires. The practical importance of the research lies in the use of measures of asymmetry and kurtosis for early detection of fires. The measures of asymmetry and kurtosis for sampling the final size of an arbitrary dangerous parameter of the gas environment are substantiated. The proposed measures make it possible to investigate the peculiarities of the coefficients of asymmetry and kurtosis in relation to the selective distribution of an arbitrary dangerous parameter of the gas environment. At the same time, it becomes possible to numerically determine the degree of difference of the sample distributions of dangerous parameters from the Gaussian, as well as the features of such measures. Experiments were conducted to determine the degree of asymmetry and excess of dangerous parameters of the gas environment in the laboratory chamber at the intervals of the absence and presence of ignition of the test materials. The obtained results indicate that on the intervals of absence and presence of fires, the selective distributions of dangerous parameters of the gas environment differ from the Gaussian distribution. Distributions are complex and individual in nature. Features of measures of asymmetry and kurtosis depend on the type of ignition material. It was established that the maximum values of the modulus of increase in the degree of asymmetry are characteristic for the carbon monoxide concentration (2.939) during the ignition of paper, for the smoke density (3.098) during the ignition of textiles, as well as for the temperature during the ignition of alcohol (7.163) and wood (1.06). It was determined that the maximum values of the modulus of excess measure increase are characteristic for smoke density (4.678) when paper, wood (1.652) and textiles (28.932) ignite, as well as for temperature (49.377) when alcohol ignites

Section: The Object Of the Study Is The Coefficients Of Asymmetry And...mentioning

confidence: 99%

Section: E D Esmentioning

confidence: 99%

Section: E D Esmentioning

confidence: 99%

See 1 more Smart Citation

Revealing the peculiarities of asymmetry and kurtosis coefficients of gas medium parameters in premises during fire

Pospelov,

Meleshchenko,

Bezuhla

et al. 2023

“…Usually, any threats and dangerous events are assessed by the level of damage they cause and the frequency of their occurrence. From the point of view of the maximum frequency of occurrence and the magnitude of damage, there are threats and dangerous events caused by fires in the premises (FP) [9]. Significant damage from FP is explained both by harm to human health [10,11] and to the objects themselves [12].…”

Section: Introductionmentioning

confidence: 99%

Revealing the peculiarities of average bicoherence of frequencies in the spectra of dangerous parameters of the gas environment during fire

Поспелов¹,

Andronov

Rybka

et al. 2023

The object of this study is a change in the hazardous parameters of the gas environment when materials are ignited in the premises. The subject is the features of the average bicoherence of the frequencies of the spectra of changes in the hazardous parameters of the gas environment when materials are ignited. The importance of such studies is based on the fact that the examined features can be used for the early detection of fires. The value of the average bicoherence is proposed to be determined for each frequency, taking into account the average value of the cosine argument of the complex bispectrum for a given frequency interval. It was established that the values of the average bicoherence of the spectrum of changes in the temperature of the gaseous medium in the interval of no ignition of the materials, averaged by frequency in the range of 0–2 Hz, lie in the range from ‒0.052 to ‒0.35. At the same time, the frequency-averaged values of mean bicoherence at the ignition interval of materials lie in the range of ‒0.128 to +0.155. Averaged in the frequency range of 0–2 Hz, the value of the mean bicoherence of the spectrum of changes in smoke density in the interval of absence of ignition of materials lies in the range from ‒0.018 to +0.568. In the presence of fires, this value is in the range from –0.244 to +0.23. At the same time, the average value of the average bicoherence of the spectrum of changes in the concentration of carbon monoxide of the gas medium for test materials, averaged in the range from 0 to 2 Hz, ranges from +0.016 to +0.109. In the case of ignition of materials, the average values range from +0.0007 to +0.053, except for ignition of wood (+0.117). In general, the revealed features of the average bicoherence of the frequency components of the spectra of changes in the hazardous parameters of the gas environment indicate the possibility of their use to identify fires and prevent fires

“…At the same time, the highest intensity of dangerous events is associated with fires (F) [3]. Such events pose both a serious threat to human life and cause partial or complete destruction of objects for various purposes [4]. Indirect factors of fire fighting, accompanying the processes of localization and elimination of fires, also negatively affect the environment.…”

Section: Introductionmentioning

confidence: 99%

Features of the coefficient of variation of parameters of the gas environment in fire in the premises

Pospelov,

Bezuhla,

Kozar

et al. 2023

The object of the study is the selective coefficient of variation of dangerous parameters of the gas environment during the ignition of materials. The measure of the sample coefficient of variation of an arbitrary hazardous parameter of the gas environment observed at an arbitrary time interval is substantiated. The representativeness error of the measure of the sampling coefficient of variation, which depends on the value of the measure and the sample size, was determined. The measure allows you to numerically determine its value for an arbitrary observation interval. The difference in the measure at the intervals corresponding to the reliable absence and occurrence of ignition allows to detect the occurrence of ignition of the material. According to the results of laboratory studies, the measures of the sample coefficient of variation for carbon monoxide concentration, smoke density, and temperature of the gas medium in the laboratory chamber at intervals of absence and appearance of ignition of alcohol, paper, wood, and textiles were determined. It was established that the dangerous parameters of the gas environment at the intervals of absence and presence of ignition are characterized by different values of the increase in the measure of the sample coefficient of variation. For example, it is determined that the ignition of alcohol causes the maximum increase in the measure for carbon monoxide concentration from 0.135 to 0.441, for smoke density from 0.629 to 0.805, and for temperature from 0.001 to 0.115. When paper catches fire, the measure for carbon monoxide concentration and temperature increases from 0.0026 to 0.140 and from 0.0019 to 0.05, respectively. When burning wood, the measure for carbon monoxide concentration and temperature increases from 0.0072 to 0.177 and from 0.0067 to 0.016, respectively. The obtained results, provided that the hazardous parameters of the gas environment in the premises are measured and the sample coefficient of variation is calculated in practice, make it possible to use them in the creation of early fire detection systems