Summary Background The biological effects of noise depend on its physical parameters, combination with other hazards, the content of acoustic signals. This article aimed to analyze the difference in biological effects caused by the selection of nonverbal and verbal signals in conditions of a high level of work intensity. Methods Work conditions, physical characteristics of noise, levels of work intensity were studied among 75 telephone operators and 96 geophone operators. Levels of permanent hearing thresholds, evaluated by pure-tone audiometry, and results of self-estimation of operators’ health were compared. The contribution of the content of acoustic signals in the shifting of hearing thresholds was evaluated by the one-way analysis of variance. Results Selection of acoustic signals in the noise background (< 65 dB), in conditions of high work intensity, causes a significant increase of permanent hearing thresholds in both studied groups comparing to the non-noise exposed population. A combination of the high level of work intensity and distinguishing of nonverbal acoustic messages leads to significant deterioration of health resulting in decreasing of hearing sensitivity and a number of complaints on the state of health (p < 0.05). The content of acoustic signals significantly contributes to the biological effects of the nose. Conclusion Obtained results testify necessity to revise safe criteria of noise levels for workers, engaged in selection, recognition and distinguishing of acoustic messages in the noise background combined with a high level of work intensity. In case when the energy of the acoustic field cannot be reduced, occupational safety measures should focus on decreasing of work intensity.

Цель. Исследование влияния компонентного состава и технологических параметров формирования наносодержащих биополимерных пленок на их лечебные и физико-механические свойства. Материалы и методы. Изучали биополимерные пленки для лечения ран, содержащие желатин, поливиниловый спирт, глицерин, молочную кислоту, дистиллированную воду и нанооксид цинка, изготовленные при различных технологических режимах. Исследовали эластичность, время деградации, паропроницаемость пленок. Лечебные свойства пленок оценивали по результатам измерения диаметра защитного действия. Результаты. Лечебные свойства биополимерной пленки напрямую связаны с диаметром защитного действия. Исследованиями установлено, что диаметр защитного действия пленок, содержащих нанооксид цинка, растет как при увеличении соотношения концентраций компонентов смеси, так и при увеличении содержания нанооксида цинка, достигая при его содержании 197 мг максимума-20,5 мм. Увеличение времени выдержки при нагревании сначала приводит к снижению диаметра защитного действия, который достигает минимума, а в дальнейшем несколько увеличивается. Увеличение температуры нагревания отрицательно влияет на лечебные свойства пленки, что связано с уплотнением ее структуры. Время деградации пленки растет с увеличением соотношения концентраций компонентов, содержания нанооксида цинка и температуры нагревания смеси. Исследовано влияние состава и режимов получения биополимерной пленки на эластичность, время деградации и паропроницаемость. Введение в состав пленки нанооксида цинка сначала увеличивает ее паропроницаемость, которая после достижения максимума снижается. Биополимерная пленка − экологически безопасна, в результате ее деструкции выделяется вода и углекислый газ. Нанооксид цинка − слаботоксичное, неагрессивное соединение, присутствует в незначительном количестве в связанном состоянии в продуктах деструкции пленки. Заключение. Проведенные исследования показали, что лечебные свойства биополимерных пленок зависят от концентрации в них частиц нанооксида цинка. Деградация пленок обеспечивает дозированную доставку лекарств в область поражения. Ключевые слова: лечение ран, наносодержащие биополимерные пленки, лечебное действие, физикомеханические свойства, экологически безопасные полимеры, утилизация биополимеров Objective. To investigate the influence of component composition and technological parameters of the formation of nano-containing biopolymer films on their therapeutic and physico-mechanical properties. Methods. The authors studied nano-containing biopolymer films for wound treatment, which had contained gelatin, polyvinyl alcohol, glycerol, lactic acid, distilled water and zinc nano oxide with various technological mode manufactured. The studied options were as follows: elasticity, degradation time, vapor permeability of biopolymer films. Therapeutic properties of biopolymer films were evaluated based on the results of measuring the protective action diameter. Results. The biopolymer film treatment properties are directly related to the diameter of the protective action. It h...

No abstract

The primary objective of the paper was to determine the user based on its keystroke dynamics using the methods of machine learning. Such kind of a problem can be formulated as a classification task. To solve this task, four methods of supervised machine learning were employed, namely, logistic regression, support vector machines, random forest, and neural network. Each of three users typed the same word that had 7 symbols 600 times. The row of the dataset consists of 7 values that are the time period during which the particular key was pressed. The ground truth values are the user id. Before the application of machine learning classification methods, the features were transformed to z-score. The classification metrics were obtained for each applied method. The following parameters were determined: precision, recall, f1-score, support, prediction, and area under the receiver operating characteristic curve (AUC). The obtained AUC score was quite high. The lowest AUC score equal to 0.928 was achieved in the case of linear regression classifier. The highest AUC score was in the case of neural network classifier. The method of support vector machines and random forest showed slightly lower results as compared with neural network method. The same pattern is true for precision, recall and F1-score. Nevertheless, the obtained classification metrics are quite high in every case. Therefore, the methods of machine learning can be efficiently used to classify the user based on keystroke patterns. The most recommended method to solve such kind of a problem is neural network.

1 Івано-Франківський національний технічний університет нафти і газу, м. Івано-Франківськ, Україна 2 Івано-Франківський національний медичний університет, м. Івано-Франківськ, Україна ПЕРСПЕКТИВИ ЗАСТОСУВАННЯ ПОЛІМЕРНИХ ВІДХОДІВ ДЛЯ ПРИГОТУВАННЯ ПОЛЕГШЕНИХ ТАМПОНАЖНИХ РОЗЧИНІВМетою дослідження є отримання полегшених тампонажних розчинів, наповнених полімерними відходами для кріплення нафтових і газових свердловин. Задачеюпідвищення ступеня зчеплення полімерного наповнювача з цементною матрицею, що дасть змогу повною мірою використати переваги дисперсно-армованих композитів. Для створення полегшених тампонажних розчинів на основі цементу їх було наповнено полімерними відходами. Нарізані відходи, перед додаванням до цементу, механічно активували з одночасним введенням у процесі активації поверхнево-активної речовини. Досліджували суміші з додаванням попередньо подрібнених та механічно активованих відходів ПЕТФпляшок у кількості від 0,5 % до 16,5 % від маси цементу з кроком 0,25 % із додаванням поверхневоактивних речовин та змінній температурі. Дослідженнями встановлено: наповнювачі розміром до 0,5×10 мм, під впливом сегрегації та великої питомої поверхні, на яку осів цемент, опускаються на дно розчину; оптимальним є подрібнення наповнювача 0,3×8 мм; надлишок ПАР на поверхні наповнювача не підвищує зчеплення полімеру з цементним каменем, а сповільнює процес тужавіння та набирання міцності внаслідок виникнення процесу ковзання на поверхні полімеру. Перспективними дослідженнями є нанесення нанопокриття з ПАР на поверхню полімерного наповнювача, яке має виключити ковзання та збільшить адгезію полімеру до цементного каменю.Ключові слова: утилізація полімерів; тампонаж свердловин; армування бетонів; полімерні волокна.

The most hygienically safe process of recycling polymers is mechanical recycling, which does not cause the destruction of polymers, products of which dangerously affect all components of the environment and man. The purpose of the study is to predict the non-carcinogenic risk to public health from the production of mechanical processing of secondary polymers, depending on the presence or absence of the stage of mechanical activation in the processing process. Materials and methods: sanitary-epidemiological examination; risk assessment of dangerous factors for public health; instrumental assessment methods; statistical processing of results – determination of arithmetic mean values, standard error, quadratic deviation. Results and discussion. It is established that the total indicators of air pollution by polymer dust, nitrogen dioxide and carbon monoxide do not exceed the permissible level of pollution, and the degree of danger of this category of production is assessed as safe. Analysis of the obtained values of hazard coefficients of chemicals for the production of mechanical processing of secondary polymer raw materials without the stage of mechanical activation showed that the risk level for the maximum concentration of polymer dust and nitrogen dioxin at a distance of 25 m is assessed as alarming. The hazard factor for the maximum concentration of carbon monoxide at all distances studied did not exceed the permissible limits. For the production of mechanical processing of secondary polymer raw materials with the stage of mechanical activation, the level of risk for any of the test substances and at all distances studied did not exceed the allowable. Conclusion. Indices of danger of impact on individual organs and systems of the body (respiratory system, central nervous system, cardiovascular system, blood, eyes) of the investigated substances (polymer dust, nitrogen dioxide, carbon monoxide) at a distance of 50 m from the processing of secondary polymer raw materials without stages of mechanical activation are admissible, and for production with a stage of mechanical activation – minimum. It is established that according to the indicators of non-carcinogenic risk, sanitary-protection zone of production facilities for mechanical processing of secondary polymer raw materials without the stage of mechanical activation cannot be less than 50 m, and with the stage of mechanical activation can be reduced to 25 m

Annotation. The most hygienically safe process of recycling polymers is mechanical recycling, which does not cause the destruction of polymers, which dangerously affect all components of the environment and man. The purpose of the study is to assess the level of risk of adverse effects on the health of the population living under the influence of mechanical processing of secondary polymers, depending on the presence or absence of the stage of mechanical activation in the processing process. Research methods: sanitary-epidemiological examination; risk assessment of dangerous factors for public health; instrumental assessment methods; statistical processing of results – determination of arithmetic mean values, standard error, quadratic deviation. It was found that the total indicators of air pollution, calculated on the maximum concentrations of specific pollutants at distances for the processing of polymers without the stage of mechanical activation of 15 m – the level of pollution was assessed as alarming, and at distances of 25 and 50 m as acceptable. For the process of processing polymers with a stage of mechanical activation, at all distances from the emission source (15, 25 and 50 m) the level of contamination was assessed as acceptable. To assess the impact of air pollution in the area of impact of polymer processing on the health of the population, the risk factors for the development of non-carcinogenic effects are more informative than the indicators of pollution. The critical human organs and systems most affected by polymer processing are: the respiratory system, the cardiovascular system, the liver, the kidneys, the central nervous system, and the blood. In order to reduce the man-caused load of enterprises for mechanical processing of secondary polymer raw materials, it is necessary to introduce in-depth purification units for air emitted into the atmosphere and switch to safer fuels.

No abstract