Construction of A Method for Detecting Arbitrary Hazard Pollutants in the Atmospheric Air Based on the Structural Function of the Current Pollutant Concentrations

This paper reports the construction of a method for calculating the structural function within a moving window of the fixed size, based on measuring the vector of current concentrations of arbitrary air pollutants. The use of a moving window makes it possible to reveal the current moments of the emergence of inhomogeneities in the polluted atmosphere. In this case, the time shift of the structural function reveals the corresponding time scale of this heterogeneity. It has been shown that, in contrast to the known method, the proposed method makes it possible to reveal the dynamics of the levels and scales of local inhomogeneities of the polluted air using only the current measurements of concentration for an arbitrary number of pollutants. It is noted that the method does not use information about the current meteorological conditions of the atmosphere and the features of urban infrastructure near a pollution control point. Therefore, the method is universal; it could be applied to arbitrary control points of atmospheric pollution across various territories of states. The efficiency of the proposed method was tested using the example of actual measurements of the concentrations of urban air pollutants involving formaldehyde, ammonia, and nitrogen dioxide. The reported results generally indicate the applicability of the proposed method. It has been experimentally established that the method makes it possible to identify, in real time, the areas of local inhomogeneities characteristic of hazardous air pollution associated with the absence of dispersion and accumulation of pollutants in the air. In addition, the method makes it possible to detect in real time both the levels and the scale of inhomogeneities in the polluted atmosphere. It has been experimentally established that before the occurrence of the tested reliable emergency in a polluted atmosphere, the level of local heterogeneity was 0.015 units at its time scale corresponding to 8 counts. Next, by the time of the emergency, the level of heterogeneity decreased to 0.0025 units at the time scale corresponding to 2 counts. It has been experimentally established that for this case the forecast time of the occurrence of an emergency was 4 counts or 24 hour

Development of A Method for Detecting Dangerous States of Polluted Atmospheric Air Based on the Current Recurrence of the Combined Risk

A method has been developed to detect hazardous conditions of contaminated air in urban areas in real time for an arbitrary number of pollutants. The method is based on restoring the hidden dynamics of the combined risk of instantaneous action on the basis of the current measurements of the concentration of pollutants at the point of control. Other data on current conditions at the point of control are not used in the developed method. Therefore, the method, in contrast to known analogs, is universal and can be applied for arbitrary conditions and control points. At the same time, the restored dynamics of the level of the combined risk of instantaneous action makes it possible not only to identify dangerous conditions relating to contaminated atmospheric air but, on the basis of the current recurrence of combined risk levels, to assess the probability of detecting and predicting dangerous levels in the combined risk of instantaneous action in real time at the predefined point of control. Using the developed method at several control points in an arbitrary area would make it possible to determine the space-time distribution of the levels of the combined risk of instantaneous action of atmospheric pollution on the population within a territory. Experimental measurements of the concentration of formaldehyde, ammonia, and nitrogen dioxide in the atmosphere have been performed at the point of control within an industrial city with an air pollution level of 37 units on the AQC scale (USA). Based on the measurements, the method has been confirmed to be feasible. It was established that at the time of a credible dangerous event, the level of the combined risk of instantaneous action was approximately 10-3 with a single probability of this level. This level of the combined risk is about 105 times higher than the corresponding upper limit of permissible individual risk. It is shown that the maximum forecast time of the dangerous level of combined risk under the considered conditions does not exceed 18 hour

Development of the Correlation Method for Operative Detection of Recurrent States

The correlation method for operative detection of recurrent states in complex dynamical systems at irregular measurements was proposed. The concepts of correlation for the case of the vectors of states of the trajectory of dynamics of complex systems and estimates of vectors correlation for a fixed length fragment moving along the trajectory were generalized. The space with scalar product of states vectors is used to implement the method. Estimation of the magnitudes of correlations of state vectors makes it possible to interpret them as corresponding levels of energy interaction of states vectors and to detect degree of their recurrence. In this case, calculation of the magnitudes of correlation are carried out only based on the known measurements of the state vector and does not require determining the threshold and the method of distance calculation, traditionally used in the methods of recurrent plots. The efficiency of the proposed method was tested on a specific example of experimental data of the actual dynamics of the vector of states of pollution of the urban atmosphere. The following gas pollutants were considered as components of the vector of state: formaldehyde, ammonia and carbon dioxide. The obtained results in general indicate the efficiency of the proposed method. It was established experimentally that the correlation method in case of irregular measurements of atmospheric contaminations ensures the authenticity of detection of recurrent states, corresponding to maximum correlation of states. In this case, the correlation assessment should be conducted for a movable fragment of a trajectory of the states vector. The length of the fragment should not be more than 10 response

Use of Uncertainty Function for Identification of Hazardous States of Atmospheric Pollution Vector

The use of estimation of the values of the uncertainty function to identify hazardous states of an arbitrary atmospheric pollution vector is considered. At the same time, it is proposed to estimate the uncertainty function in a fixed-width window moving along the trajectory of the state vector. This allows not only identifying the occurrence of hazardous states of atmospheric pollution, but also determining their radial velocity relative to the monitoring post. Zero radial velocity of hazardous states of atmospheric pollution allows identifying current states of no pollution dispersion in the atmosphere. These states turn out to be especially dangerous, since they lead to the accumulation of pollution and an increase in their concentration in the atmosphere. Verification of the possibility of using the uncertainty function to identify hazardous states of the atmospheric pollution vector was carried out using experimental data. At the same time, formaldehyde, ammonia and carbon monoxide were considered as hazardous components of the state vector of atmospheric pollution. The verification results generally indicate the possibility of using the uncertainty function to identify hazardous states of the atmospheric pollution vector. The use of uncertainty function is found to be invariant with respect to the irregularity of recording of atmospheric pollution at stationary monitoring posts. It is shown that the use of uncertainty function enables the identification of hazardous states characterized not only by exceeding the maximum permissible concentrations, but also by the zero radial velocity relative to the monitoring point. It is experimentally found that in order to identify hazardous states of atmospheric pollution, the window length should be from 4 to 8 reading

Construction of A Method for Detecting Arbitrary Hazard Pollutants in the Atmospheric Air Based on the Structural Function of the Current Pollutant Concentrations

This paper reports the construction of a method for calculating the structural function within a moving window of the fixed size, based on measuring the vector of current concentrations of arbitrary air pollutants. The use of a moving window makes it possible to reveal the current moments of the emergence of inhomogeneities in the polluted atmosphere. In this case, the time shift of the structural function reveals the corresponding time scale of this heterogeneity. It has been shown that, in contrast to the known method, the proposed method makes it possible to reveal the dynamics of the levels and scales of local inhomogeneities of the polluted air using only the current measurements of concentration for an arbitrary number of pollutants. It is noted that the method does not use information about the current meteorological conditions of the atmosphere and the features of urban infrastructure near a pollution control point. Therefore, the method is universal; it could be applied to arbitrary control points of atmospheric pollution across various territories of states. The efficiency of the proposed method was tested using the example of actual measurements of the concentrations of urban air pollutants involving formaldehyde, ammonia, and nitrogen dioxide. The reported results generally indicate the applicability of the proposed method. It has been experimentally established that the method makes it possible to identify, in real time, the areas of local inhomogeneities characteristic of hazardous air pollution associated with the absence of dispersion and accumulation of pollutants in the air. In addition, the method makes it possible to detect in real time both the levels and the scale of inhomogeneities in the polluted atmosphere. It has been experimentally established that before the occurrence of the tested reliable emergency in a polluted atmosphere, the level of local heterogeneity was 0.015 units at its time scale corresponding to 8 counts. Next, by the time of the emergency, the level of heterogeneity decreased to 0.0025 units at the time scale corresponding to 2 counts. It has been experimentally established that for this case the forecast time of the occurrence of an emergency was 4 counts or 24 hour

Development of the Correlation Method for Operative Detection of Recurrent States

The correlation method for operative detection of recurrent states in complex dynamical systems at irregular measurements was proposed. The concepts of correlation for the case of the vectors of states of the trajectory of dynamics of complex systems and estimates of vectors correlation for a fixed length fragment moving along the trajectory were generalized. The space with scalar product of states vectors is used to implement the method. Estimation of the magnitudes of correlations of state vectors makes it possible to interpret them as corresponding levels of energy interaction of states vectors and to detect degree of their recurrence. In this case, calculation of the magnitudes of correlation are carried out only based on the known measurements of the state vector and does not require determining the threshold and the method of distance calculation, traditionally used in the methods of recurrent plots. The efficiency of the proposed method was tested on a specific example of experimental data of the actual dynamics of the vector of states of pollution of the urban atmosphere. The following gas pollutants were considered as components of the vector of state: formaldehyde, ammonia and carbon dioxide. The obtained results in general indicate the efficiency of the proposed method. It was established experimentally that the correlation method in case of irregular measurements of atmospheric contaminations ensures the authenticity of detection of recurrent states, corresponding to maximum correlation of states. In this case, the correlation assessment should be conducted for a movable fragment of a trajectory of the states vector. The length of the fragment should not be more than 10 response

Development of the Method of Operational Forecasting of Fire in the Premises of Objects Under Real Conditions

A method for operational forecasting of fires is proposed that enables the sequential implementation of five procedures. The method development is necessary to predict early fires in premises in order to take measures to prevent them from escalating into an uncontrolled combustion phase ‒ a fire. As a result of research, it was found that a short-term forecast of the recurrence of increments of the air conditions by one step, based on the current measure of recurrence, is an effective indicator of early fires in premises. At the same time, it was found that before the moment of ignition of the material, the state of the air environment is characterized by dynamic stability, which is described by an irregular and time-dependent random change in the recurrence of the states of the vector of current increments of the state of the air environment. The values of the indicated levels of recurrence of the state increments are determined by the probability levels of 0.67 and 0.1, respectively. The probability of recurrence of state increments of 0.67 is characteristic of a larger number of measured states. When the material is ignited, the dynamics of the probability of recurrence of state increments change abruptly. There is a transition from two to one level of recurrence, close to zero probability ‒ the loss of dynamic stability (in the region of count 250). Further dynamics are characterized by the appearance of separate random recurrent increments corresponding to the instability of the air environment in the premises. In the course of the experiment, it was found that the accuracy of predicting a fire by the proposed method ranges from 4.48 % to 12.79 %, which generally indicates its efficiency. The obtained data prove useful in the development of new systems that early warn of fire in premises, as well as in the modernization of existing systems and means of fire protection of premise