bluuebunny/crossref_metadata_2025 huggingface dataset:
Short-term fire forecast based on air state gain recurrence and zero-order brown model
Authors: Pospelov Boris , Rybka Evgenіy , Meleshchenko Ruslan , Krainiukov Olekcii , Biryukov Igor , Butenko Tetiana , Yashchenko Oleksandr , Bezuhla Yuliia , Karpets Kostiantyn , Vasylchenko Ruslan
Published: July 2021

Possibilities of parameterization of the zero-order Brown model for indoor air forecasting based on the current measure of air state gain recurrence are considered. The key to the zero-order parametric Brown forecasting model is the selection of the smoothing parameter, which characterizes forecast adaptability to the current air state gain recurrence measure. It is shown that for effective short-term indoor fire forecast, the Brown model parameter must be selected from the out-of-limit set defined by 1 and 2. The out-of-limit set for the Brown model parameter is an area of effective fire forecasting based on the measure of current indoor air state gain recurrence. Errors of fire forecast based on the parameterized zero-order Brown model in the case of the classical and out-of-limit sets of the model parameters are investigated using the example of ignition of various materials in a laboratory chamber. As quantitative indicators of forecast quality, the absolute and mean forecast errors exponentially smoothed with a parameter of 0.4 are investigated. It was found that for alcohol, the smoothed absolute and mean forecast errors for the classical smoothing parameter in the no-ignition interval do not exceed 20 %. At the same time, for the out-of-limit case, the indicated forecast errors are, on average, an order of magnitude smaller. Similar ratios for forecast errors remain in paper, wood and textile ignition. However, for the transition zone corresponding to the time of material ignition, a sharp decrease in the current measure of chamber air state gain recurrence is observed. It was found that for this zone, the smoothed absolute forecast error for alcohol is about 2 % if the model parameter is selected from the classical set. If the model parameter is selected from the out-of-limit set, the forecast error is about 0.2 %. The results generally demonstrate significant advantages of using the zero-order Brown parametric model with out-of-limit model parameters for indoor fire forecasting
Improving a model of object recognition in images based on a convolutional neural network
Authors: Knysh Bogdan , Kulyk Yaroslav
Published: July 2021

This paper considers a model of object recognition in images using convolutional neural networks; the efficiency of the model-based process involving the training of deep layers in convolutional neural networks has been studied. There are objective difficulties associated with determining the optimal characteristics of neural networks, so there is an issue related to retraining a neural network. Eliminating the retraining by determining only the optimal number of epochs is insufficient since it does not provide high accuracy.
The requirements for the set of images for model training and verification have been defined. These requirements are better met by the INRIA image set (France).
GoogLeNet (USA) has been established to be a trained model that can perform object recognition on images but the object recognition reliability is insufficient. Therefore, it becomes necessary to improve the effectiveness of object recognition in images. It is advisable to use the GoogLeNet architecture to build a specialized model that, by changing the parameters and retraining some layers, could allow for better recognition of objects in images.
Ten models were trained using the following parameters: learning speed, the number of epochs, an optimization algorithm, the type of learning speed change, a gamma or power coefficient, a pre-trained model.
A convolutional neural network has been developed to improve the precision and efficiency of object recognition in images. The optimal neural network training parameters were determined: training speed, 0.000025; the number of epochs, 100; a power coefficient, 0.25, etc. A 3 % increase in precision was obtained, which makes it possible to assert the proper choice of the architecture for the developed network and the selection of its parameters. That allows this network to be used for practical tasks of object recognition in images.
Building a model and an algorithm for modeling the movement of people carrying goods when they are evacuated from premises
Authors: Pankratov Alexander , Komyak Valentina , Kyazim Kyazimov Tahir oglu , Komyak Vladimir , Tarasenko Olexandr , Antoshkin Oleksiy , Mishcheriakov Iurii , Dolhodush Mykhailo
Published: July 2021

Evacuation is often the only way to save a person who is in a life-threatening situation. At present, evacuation software is used to simulate the movement of human flows, which does not always reflect the real processes of their movement. Therefore, it is a relevant task to build models for modeling the movement of human flows for different types of emergencies, different categories of human movement, and various spatial forms of their representation. Such a task arises when evacuating people from premises for various functional purposes.
During evacuation, people often carry some goods. When people move carrying some goods, their horizontal projection takes a more complex shape than an ellipse or circle considered in earlier studies. Moreover, in practice, there is often a task to model the movement of people taking into consideration the maximum permissible distances between them.
This paper reports the new quasi-phi functions of interaction between the ellipse and rectangle accounting for the maximum allowable distances between them. The proposed mathematical apparatus has made it possible to formalize the interaction between objects, thereby enabling the construction of a well-substantiated mathematical model, as well as the methods and algorithms for modeling the movement of people carrying some goods.
The possibility to simulate the movement of people with certain objects has shown taking into consideration the maximum permissible distances between them. A test example of the movement of people along four corridors was simulated, in each of which there were 28 people subsequently merging into one flow. Given the uniform distribution of three types of cargo: «backpacks», «suitcases», and «bags on wheels», the movement slowed down by about 4 %. When half of the evacuees had «bags on wheels» that can move away from people at arm’s length, the slowdown was about 6 %.
Formation of a complete stress-strain curve of concrete using digital image corellation
Authors: Blikharskyy Yaroslav , Pavliv Andrii
Published: July 2021

This paper reports the development and verification of a new procedure for formation of a complete stress-strain curve of concrete with a downward region of strain by using a digital image correlation method. A new technique to build spectle patterns on the surface of concrete is described. That makes it possible to accurately enough reproduce the spectle patterns on the surface of concrete and perform a high-quality analysis of strains involving digital image correlation. The advantages of this research technique have been established when predicting the formation of internal cracks in concrete followed by their propagation. In addition, using the digital image correlation methodology makes it possible to obtain strains of the entire studied plane of the sample at each stage of loading. This procedure provides an opportunity to investigate a change in strains and the movement of individual points or areas when studying concrete surfaces. That is a relevant issue as it enables more detailed diagnostics of existing reinforced concrete structures. To check the accuracy of this procedure application, a mechanical gauge with an accuracy of 0.001 mm was additionally installed. 2 high-speed monochrome CCD cameras with different lenses were used in determining concrete strains involving the digital image correlation technique. The deformations were controlled with a period of time every 250 ms. The load was controlled by an additional third camera with a speed of 50 frames/second. The result of the experimental study is the formed full concrete destruction diagram with a downward region of strain. The deviation of the results of strains based on the mechanical gauge with an accuracy of 0.001 mm with a base of 200 mm from those acquired by the digital image correlation procedure was mainly up to 10 %, which confirms the reliability of the results. The results of this work allow a more accurate calculation of reinforced concrete structures in the practice of design, inspection, or reinforcement of existing structures
Comparative investigation of different types of nickel foam samples for application in supercapacitors and other electrochemical devices
Authors: Kovalenko Vadym , Kotok Valerii
Published: July 2021

Nickel foam is widely used as a current lead/current collector and the basis of nickel hydroxide electrodes for various electrochemical devices – batteries, hybrid supercapacitors, devices for electrocatalytic oxidation of organic substances. The characteristics of commercial samples of nickel foam produced by Novomet-Perm (Russian Federation) obtained by electroless and then electrochemical nickel plating and Linyi Gelon LIB Co Ltd (China) obtained by electroless nickel plating were studied. The nature of passivity was determined by forming model samples of electrochemical and electroless nickel on a steel base. For the passive sample, activation was carried out by applying a layer of electrochemical nickel from an impact nickel plating solution. Activated, non-activated samples of nickel foam, as well as model samples, were studied by the methods of cyclic voltammetry and galvanostatic charge-discharge cycling in the supercapacitor mode. Comparative analysis of Chinese-made and Russian-made nickel foam samples showed significant passivity of the former – in cyclic voltammetry, the activity was 4.8 times lower, with galvanostatic charge-discharge cycling – 2.59 times lower. It was suggested that high passivity was determined by the fact that the sample consisted of Ni-P or Ni-B alloy. This assumption was proved by the method of natural simulation. The electrochemical activity of electroless nickel was 1.25 times lower than that of electrochemical nickel (according to cyclic voltammetry data) and 1.58 times lower (according to galvanostatic cycling data). For the first time, Chinese-made nickel foam (electroless nickel) was activated by applying a layer of electrochemical nickel from an impact nickel electrolyte. The high activation efficiency was shown as follows – on the cyclic curve, the specific current of the anodic peak increased 8.71 times, and with galvanostatic cycling, the increase in specific capacity was from 1.73 times (at i=120 mA/cm2) to 4.84 times (at i=20 mA/cm2)
Development of binary information compression methods based on the binomial numerical function
Authors: Kulyk Igor , Berezhna Olga , Novhorodtsev Anatoliy , Shevchenko Maryna
Published: July 2021

The application of data compression methods is an effective means of improving the performance of information systems. At the same time, interest is aroused to the methods of compression without information loss which are distinguished by their versatility, low needs of costs during implementation, and the possibility of self-control.
In this regard, the application of binomial numbering systems is promising. The numerical function of the binomial numbering system is used for compression. It makes it possible to put sequences in one-to-one compliance with their numbers. In this case, the transition from binary combinations to binomial numbers is used as an intermediate stage.
During the study, theorems were formulated that indicate properties of compressing and restoring the mappings as well as the ways of their implementation. Models of compression processes were obtained on the basis of a numerical function, both for the case of compressible equilibrium combinations and the case when sequences of a general form are to be compressed. The compression models include coding steps based on binary binomials.
The study results show the effectiveness of applying the compression based on the binomial numerical function. A 1.02 times increase in speed of information transmission through a communication channel was observed in the worst case and 18.29 times in the best case depending on the number of ones in 128-bit equilibrium combinations. The proposed methods are advantageous due to their high compression ratio (from 1.01 to 16 times for general 128-bit sequences) and versatility: combinations are compressed in which the number of ones is 75 % of their total variation range. The developed methods ensure control of errors during conversions. They are undemanding to computation resources and feature low implementation costs.
Building a model of the integrity of information resources within an enterprise management system
Authors: Ospanova Gulmira , Kukharenko Evgeniya , Ievlanov Maksym , Panforova Iryna
Published: July 2021

In addressing the integrity of documents in modern information systems, the focus is on protecting them from unauthorized user changes. At the same time, the solution to the problem of ensuring the preservation of the composition, content, and interaction of documents has almost not been considered. However, such a task often has to be solved during the operation of information systems, as well as enterprise management systems handling unstable business processes.
To address this issue, an approach has been proposed to unify solutions to the task related to the integrity of paper-based documents circulating within an enterprise management system, as well as electronic documents and stored information system data. The existing service registry models have been analyzed, aimed to formally describe the resources of the information system and an enterprise management system based on this information system. Models of elements of the unified information resource registry have been modified, and a model for ensuring the integrity of an enterprise's information resources has been developed. The proposed improvements make it possible to use current and multi-tested methods to address the integrity of information resources.
Experimental testing of improved models of a unified information resource registry has been carried out. The task of ensuring integrity was considered for a regulatory document that should change its name and its composition as a result of external and internal factors. It has been shown that the application of the proposed results makes it possible to solve the task of ensuring the integrity of information resources such as paper-based regulations of an enterprise management system, within the framework of a unified registry of information resources by existing database management systems
Influence of sesame flour on physicochemical properties of sour milk drinks
Authors: Qin Xuanxuan , Samilyk Maryna , Luo Yanghe , Sokolenko Viktoriia
Published: July 2021

This study aimed to investigate the technological properties of kefir fortified with defatted sesame flour (DSF). We have developed a recipe for producing kefir with the addition of 0, 2, 4, 6, 8 % DSF. The physicochemical parameters (pH, titratable acidity) and rheological properties (water-holding capacity, viscosity) of the samples within 28 days of storage were studied. All the samples were stored at a temperature of 4 °C. Nuclear magnetic resonance and chromatographic analysis were performed to determine the optimal shelf life of the product. It was found that fermentation ends on the seventh day of storage, while a low content of free water is observed. The recommended optimal storage time for kefir enriched with DSF is within 14 days. The introduction of 2 % DSF in kefir increases the content of vitamin E by three times (from 0.32 to 0.93 mg/100 g) and the content of proteins – by 1 % (from 3.36 to 4.3 %). The result showed that the pH value decreases with the introduction of DSF and is within the normal range during the entire storage period of the product (from 4.38 to 4.07). In this case, the total titratable acidity increases from 112.07 to 163.52 °T. An increase in viscosity (by 3 Pa∙s) and water-holding capacity (by almost 6 %) is observed with the addition of 2 % additive. Due to the high water-holding capacity and viscosity, dietary fiber content (up to 0.68 %), kefir supplemented with DSF showed high storage stability. The addition of 2 % DSF to kefir can increase the nutritional value and improve the structural stability of the product. DSF is a waste product with a bright prospect for use in the manufacture of fermented milk drinks
Design of systems for integrated processing of dairy raw materials in the cheese industry
Authors: Yatskov Mykola , Korchyk Natalia , Besediuk Volodymyr
Published: July 2021

For the functioning of integrated systems for processing dairy raw materials in the cheesemaking industry, it is proposed to consider the basic concepts of synthesis of production systems. In order to implement the concept of waste minimization, it is proposed to separate the industrial wastewater into flows based on the concentration and values of the main parameters, as well as to protect the cheese whey from entering the water treatment facilities and direct it for disposal. The possibilities of implementing the concepts of deep raw materials processing into a target product have been analyzed, as well as the full utilization of raw and auxiliary materials. To this end, an experimental study was performed on the extraction of protein clots and adjusting the buffer capacity of infant dairy products using cheese whey. The study results indicate the insufficient effect of extracting the protein clot from whey (5–50 %) by combining the thermal and chemical processes. It was established that the redox conditions of the medium, in terms of the Eh indicator, can significantly affect the results, in close connection with the pH parameter and the estimated value of rH2. It was found that the optimal conditions for the functioning of lactic acid microflora in the production of soft cheeses can be ensured by adjusting the Eh indicator through the introduction of whey of pH=4.4–4.6 units, Eh≤–0.1 V. Whey is introduced at the stage of dairy raw material fermentation, which creates optimal conditions for the formation of a clot until reaching rH2 in the range from −5 to –7, and increases the product output by 1.5–7 %. The results of the experimental study indicate the high potential of using whey desalinated by ion exchange in order to reduce the buffer capacity in terms of acidity and adjust the redox conditions for infant milk mixtures until achieving rH2=15.5–15.9. The research reported in this paper could be the basis for the further development of systems for the integrated processing of dairy raw materials in the cheesemaking industry
Advancing the multifactor model of Stochastic Frontier Analysis
Authors: Mitsel Arthur , Alimkhanova Aliya , Grigorieva Marina
Published: July 2021

The concept of efficiency is important in economic science; at present, its role in every sector of the economy is growing. Evaluating an enterprise’s efficiency makes it possible to implement a correct and profitable strategy of resource allocation, which shows its potential level Given an annual increase in the number of bankrupt enterprises, the issue of estimating the efficiency of enterprises is relevant for both their owners and managers, as well as for creditors. There are various methods and models for estimating the performance of enterprises. This work has assessed the efficiency of enterprises in the industrial sector over the period of 2017‒2018. Stochastic Frontier Analysis is based on the stochastic model of production function. The classic SFA method is based on the production function of the company, which relates the volume of output to the volume of resources consumed. At the same time, the SFA model uses several inputs (volumes of resources consumed) and only one output parameter ‒ the volume of production.
In order to achieve more precise results, a given model has been modified. The model allows several key financial indicators to be taken into consideration as outputs at the same time, based on which the financial activities of the studied economic entities are assessed. The result of the work involving open sources has revealed how the efficiency of different enterprises in the same industry changes over several years. It is shown that the modified Stochastic Frontier Analysis model could be used to assess financial stability and predict bankruptcy.
Determination of adhesion of the coating deposited by arc spraying with pulsation of atomizing air flow
Authors: Zakharova Iryna
Published: July 2021

During electric arc spraying, during the transfer of molten metal by air flow, there is a significant burnout of alloying elements with the formation of a large amount of oxides, which negatively affects the adhesion of the coating to the base. A solution to the problem of increasing the adhesion strength by using pulsation of the atomizing air flow is proposed. At the optimal frequency of the pulsed flow shut-off, the time of formation of liquid metal droplets at the ends of the electrodes coincides with the frequency of pulses of the spraying flow. As a result, the droplets acquire an optimal size, they are transported by an air flow with conservation of energy, a lower mass of oxygen and, as a consequence, a significant decrease in the oxidation of alloying elements in the sprayed material. The existing test methods of sprayed coatings for adhesion strength to the base are analyzed. The design of a modernized device for determining the adhesion strength is developed and described, which provides complex loading of the coating with a combination of tear-off and shear. The tests revealed a significant (up to two times) increase in the adhesion strength of aluminum, zinc-aluminum and steel (Sv08A) coatings applied with air pulsation. This is achieved by increasing the number of fusion zones of the coating particles between themselves and with the base. It is shown that the effect of the pulsation frequency on the adhesion strength changes along a curve with a maximum corresponding to a frequency of 70–80 Hz, regardless of the coating material. It has been established that the aluminum coating has an increased tendency to oxidation, as a result of which it is 15–20 % inferior to the zinc-aluminum coating in adhesion strength. The data obtained substantiate the use of the proposed spraying technology in production
Generalizing the sampling theorem for a frequency-time domain to sample signals under the conditions of a priori uncertainty
Authors: Kaliuzhnyi Mykola
Published: July 2021

The radio monitoring of radiation and interference with electronic means is characterized by the issue related to the structural-parametric a priori uncertainty about the type and parameters of the ensemble of signals by radio-emitting sources. Given this, it is a relevant task to devise a technique for the mathematical notation of signals in order to implement their processing, overcoming their a priori uncertainty in terms of form and parameters.
A given problem has been solved by the method of generalization and proof for the finite signals of the Whittaker-Kotelnikov-Shannon sampling theorem (WKS) in the frequency-time domain. The result of proving it is a new discrete frequency-temporal description of an arbitrary finite signal in the form of expansion into a double series on the orthogonal functions such as sinx/x, or rectangular Woodward strobe functions, with an explicit form of the phase-frequency-temporal modulation function. The properties of the sampling theorem in the frequency-time domain have been substantiated. These properties establish that the basis of the frequency-time representation is orthogonal, the accuracy of approximation by the basic functions sinx/x and rectangular Woodward strobe functions are the same, and correspond to the accuracy of the UCS theorem approximation, while the number of reference points of an arbitrary, limited in the width of the spectrum and duration, signal, now taken by frequency and time, is determined by the signal base.
The devised description of signals in the frequency-time domain has been experimentally investigated using the detection-recovery of continuous, simple pulse, and linear-frequency-modulated (LFM) radio signals. The constructive nature of the resulting description has been confirmed, which is important and useful when devising methods, procedures, and algorithms for processing signals under the conditions of structural-parametric a priori uncertainty.
Development of a solar element model using the method of fractal geometry theory
Authors: Budanov Pavlo , Kyrysov Ihor , Brovko Kostiantyn , Rudenko Dmytro , Vasiuchenko Pavlo , Nosyk Andrii
Published: July 2021

It is shown that in the existing models of the solar cell, assumptions were made about the ideally smooth surface topography, which had a significant impact on the calculation of the output parameters. It is proposed to take into account the real working area of the receiving surface of the solar cell to improve the accuracy, linearity and stability of the current-voltage characteristics. A geometric model of the structure of the receiving surface of a solar cell has been developed, which describes and takes into account geometric changes in the structure of a semiconductor conducting layer, in the presence of damaging defects in the form of local inhomogeneities, micropores and macrocracks. It was found that the receiving surface with damaging defects is a porous inhomogeneous structure and has fractal properties: self-similarity, invariance, scalability. It is proposed to determine the real working area, to use the method of the theory of fractal geometry and, as an effective quantitative parameter for assessing the change in fractal structure, to choose the value of the fractal dimension. The obtained analytical expressions for the improved model establish the relationship between the output parameters and determine the degree of filling of the current-voltage characteristic for the output power and efficiency. The computational experiment showed that the real area can be much less than the geometric area of the topological relief and is quantitatively related to the change in fractal dimension in the range from 2.31 to 2.63. The obtained data on the real area, when solving analytical expressions for the solar cell model, play an important role in ensuring the stability and linearity of the current-voltage characteristic, increasing its accuracy up to 5 %.
Development of a method for selected financing of scientific and educational institutions through targeted capital investment in the development of innovative technologies
Authors: Levchenko Iaroslava , Dmytriieva Oksana , Shevchenko Inna , Britchenko Igor , Kruhlov Vitalii , Avanesova Nina , Kudriavtseva Oksana , Solodovnik Olesia
Published: July 2021

The problem of supporting scientific and educational institutions is considered. A method of selective financing of scientific and educational institutions that create innovative technologies taking into account their investment in innovative developments is proposed. On the basis of statistical data on the indicators for assessing the activities of scientific and educational institutions and the indicator of the innovative potential of a scientific and educational institution from the production of innovations (PNn), their rating was calculated. The essence of PNn is to compare the indicators of the volumes of income of the special fund Dsfn and the volume of expenditures of the scientific and educational institution Vn.
In order to stimulate scientific and educational institutions to create innovative technologies, it was proposed to introduce targeted investments. The problem of quantifying the rate of premium on the basis of an integrated approach in terms of indicators of innovative potential from the production of innovations and the rating of a scientific and educational institution for 2 institutions (namely: K and H) has been solved. Institution K will receive a large increase, and institution N will receive a smaller increase, the value of which will be 56.23 % and 43.76 %, respectively. The results showed the independence of the indicator of the innovative potential of a scientific and educational institution from the production of innovations from the previous rating of a scientific and educational institution, or vice versa. The proposed methodology has been tested by an experimental method, targeted investments have been determined based on an integrated approach in terms of indicators of innovative potential and the rating of a scientific and educational institution.
This study is of practical interest to government authorities and grantors when allocating funds according to the vector of selective financing of scientific and educational institutions through targeted investments in the development of innovative technologies, and theoretically – to researchers dealing with issues of financial security, protectionism and public administration
Biopharmaceutical and rheometric studies in the development of a gel composition with dimethindene maleate
Authors: Popova Tetiana , Kukhtenko Halyna , Bevz Nataliia , Kukhtenko Oleksandr
Published: July 2021

Every year there is an increase in the number of cases of hypersensitivity to bites from various insects. A local allergic reaction to bites occurs within a few minutes and is accompanied by acute pain at the site of the bite, severe itching, hyperemia, the appearance of papules, tissue edema, and sometimes a small-point rash around. Considering the small number of drugs for local therapy of allergic manifestations and the unidirectional nature of their action, it is urgent to develop a drug containing the antihistamine dimethindene maleate and dexpanthenol, which plays the role of an anti-inflammatory, reparative and dermatoprotective substance.

The aim. The aim of the study is to substantiate the delivery system of dimethindene maleate and dexpanthenol based on biopharmaceutical and rheometric research methods.

Materials and methods. To determine the component composition of the active ingredient delivery system, the type of dimetindene maleate administration was substantiated by studying its solubility. As a delivery system for active pharmaceutical ingredients, hydrogels were considered, which were made using high-molecular compounds of various origins: a natural substance – xanthan gum, a semi-synthetic substance – gyroxypropyl methylcellulose, and a synthetic substance – carbomer. The rate of release of dimethindene maleate from hydrogels was estimated by studying the kinetics of release through a semipermeable membrane. The assessment of the viscoelastic properties of hydrogels was carried out by performing an oscillatory rheometry test, which makes it possible to quantitatively determine the viscous and elastic components, as well as to characterize the bioadhesive properties.

Results. Based on the results of studying the solubility of dimethindene maleate in hydrophilic non-aqueous solvents, it was determined that propylene glycol is optimal for ensuring the introduction of a substance into hydrogel bases as a solution. As a result of studying the kinetics of the release of dimethindene maleate from hydrogels, it was found that the use of carbomer as a delivery system provides the release of 28.33 % of dimethindene maleate, xanthan gum – 25 %, hydroxypropyl methylcellulose – 7.33 %. When studying the viscoelastic properties by determining the values ​​of the storage modulus G', the loss modulus G" and the damping (attenuation) factor tg δ, it was found that the carbomer-based hydrogel is a viscoelastic solid, the xanthan gum and hydroxypropyl methylcellulose-based hydrogels are a viscoelastic liquid. Bioadhesion on the surface of the skin during use has the advantage of carbomer hydrogel.

Conclusions. Based on the combination of biopharmaceutical and rheometric methods for substantiating the composition of the delivery system for dimetindene maleate and dexpanthenol, it is rational to use carbomer for further pharmacological and microbiological studies
A novel comparative chromatographic research of secoiridoid glycosides in two species of centaury herb
Authors: Gubar Svitlana , Materiienko Anna , Ivanauskas Liudas , Mishchenko Volodymyr , Vasylieva Olha , Georgiyants Victoriya
Published: July 2021

The aim: A novel comparative analysis of the secoiridoid glycosides composition in Centaurium erythraea Rafn. and Cеntaurium pulchellum (Sw.) Druce has being described. Swertiamarin has been chosen as an active marker and its comparative quantitative estimation in two species of the raw material has been carried out by HPLC method.
Materials and methods: The quantitative HPLC analysis of swertiamarin was conducted using a chromatographic column ACE 5 C18. Methanol and 0,5 % acetic acid aqueous solution were used as mobile phases; the chromatographic procedure was carried out in a gradient mode.
Results: The content of swertiamarin in the C. pulchellum herb ranges from 2.51 to 3.07 mg/100 mg. In that time swertiamarin content in C. erythraea herb varies and depends from 3.83 to 8.94 mg/100 mg. The content of swertiamarin in C. pulchellum herb is much lower than in C. erythraea herb. Taking into account this fact the possibility of using of C. pulchellum herb for medicine instead of C. erythraea herb must be proven additionally by biological experiments. Also it could be preliminary concluded that the most appropriate climate for swertiamarin accumulation in C. erythraea herb is located in Central and Eastern parts of Ukraine.
Conclusions: It was discovered that the main representative of secoiridoid glycosides in C. erythraea is swertiamarin when in C. pulchellum Druce that are represented by both sweroside and swertiamarin. A more perspective raw material – C. erythraea herb, according to the content of swertiamarin, was chosen
Substantiation of an approach to determination of ketoprofen macrogol 400 esters
Authors: Bezuglaya Elena , Zinchenko Igor , Lyapunov Nikolay , Vlasenko Hanna , Musatov Vladimir
Published: July 2021

The aim. The work is concerned with the substantiation of the approach to the identification and quantitative determination of ketoprofen macrogol 400 esters.
Materials and methods. Ketoprofen, macrogol 400, ketoprofen macrogol 400 ester (KM400E), as well as model cream-gels were studied by the following methods: absorption spectrophotometry ultraviolet (UV) and visible, high-performance liquid chromatography (HPLC), gas chromatography (GC), GC / mass spectrometry, nuclear magnetic resonance (NMR) spectrometry and thermogravimetry.
Results. It was found by GC and GC / mass spectrometry that the average molecular mass (Mr) of the test macrogol 400 is 383.50 and it contains oligomers with molecular masses from 150.17 to 546.65. KM400E, which is a mixture of esters of ketoprofen with macrogol oligomers, was synthesized. The formed esters were characterized by 1H NMR spectra. It was shown that the ratio of the average molecular mass of KM400E, calculated for monoesters, and the molecular mass of ketoprofen corresponds to the ratio of specific absorbances of solutions of ketoprofen and solutions of KM400E, this fact indicated the formation of monoesters. Taking into account the risk of variability of the fractional composition of macrogol 400 in different batches, it is advisable to quantify KM400E using ketoprofen reference standard (RS) and not KM400E RS. Using HPLC with diode array detection the peak of KM400E should be identified by the UV absorption spectrum with λmax≈255 nm, which is characteristic for ketoprofen, and the relative retention time (RRt) of the peak; KM400E should be quantified by the content of ketoprofen in this impurity.
During storage of model cream-gels the content of KM400E impurity is significantly lower than the content of ketoprofen propylene glycol ester (mixture of isomers).
Conclusions. The approach to the identification and quantitative determination of KM400E is substantiated. The analytical procedure for determination of KM400E impurity by HPLC with a diode array detection using ketoprofen RS was developed. Correctness of the procedure was proved by the results of the validation studies.
Determination of toxicological characteristics of a complex antiemeric drug based on maduramycin and nicarbazine
Authors: Dotsenko Roman , Vashchyk Yevheniia , Zakhariev Andriy , Zemlianskyi Andrii , Dotsenko Ekaterina , Seliukova Nataliia
Published: July 2021

The aim: to determine the parameters of acute toxicity of the preparative form of an antiemeric agent based on maduramycin and nicarbazine for white mice, white rats and guinea pigs with a single oral administration.

Materials and methods. Determination of acute toxicity of the formulation by oral administration was performed on 48 adult male mice, 48 adult nonlinear male rats, 48 adult male guinea pigs. To conduct an experiment on the principle analogues were formed seven experimental and one control group, 6 animal each. The dose of the formulation was calculated individually based on body weight values. It should be noted that the total volume of the emulsion of the formulation administered orally is not exceeded 1.0 cm3per 100 gram b. w.

Results. Toxicometric parameters of the formulation were calculated by the method of least squares for probit analysis of mortality curves. It was found that the LD50 of the preparative form of antiemeric agent for white mice for a single oral administration is 238.05±28.08 mg/kg, LD16 – 128.71 mg/kg, LD84 – 347.39 mg/kg, LD100 - 402, 06 mg/kg body weight, respectively.

LD50 of the preparative form of antiemeric agent for white rats with a single oral administration is 260.51±28.83 mg/kg, LD16 – 148.39 mg/kg, LD84 – 372.65 mg/kg, LD100 – 428.71 mg/kg body weight, respectively.

LD50 of the preparative form of antiemeric agent for guinea pigs for a single oral administration is 275±21.12 mg/kg, LD16 – 201.74 mg/kg, LD84 – 348.25 mg/kg, LD100 – 384.88 mg/kg body weight body respectively.

Conclusions. According to SOU 85.2-37-736: 2011 "Veterinary drugs. Determination of acute toxicity” preparative form of a complex antiemeric agent based on maduramycin and nicarbazine on the degree of toxicity can be attributed to moderately dangerous substances (3rd hazard class)
Study of the influence of the housing on the cooling efficiency of the piezoceramic electroacoustic Langevin-type transducer
Authors: Pershevska Liudmyla , Drozdenko Oleksandr , Drozdenko Kateryna , Leiko Oleksandr
Published: July 2021

The object of research is thermal processes in Langevin-type piezoceramic electroacoustic transducers (PET), taking into account the housing. The piezoceramic electroacoustic transducers heat up during operation. Overheating of the converter leads to negative consequences, accompanied by a change in the parameters, characteristics of the device, as well as the failure of the converter. Or limitation on the duration and mode of operation, output power, current, amplitude and speed of oscillation of the converter.
The paper investigates the effect of the housing on the temperature field of a Langevin-type PET by the finite element method, using modeling in SolidWorks. The results of temperature reduction of such cooling methods are shown:
– filling the housing cavity with electrical insulating liquid, gas, a mixture of thermal paste;
– use of holes in the housing;
– changing the shape of the rear cover to have radiator side fins, vertical radiator fins, cylindrical radiator fins;
– heat-resistant layer;
– use of active air cooling at three different speeds.
The most efficient 53 % and a uniform temperature field were found when filling with a mixture of thermal paste, but this solution is accompanied by additional experiments and a preparatory stage with the mixture. The cooling efficiency of 47 % was provided by active cooling – blowing with air, and this method requires additional equipment. Filling with insulating liquid gave a cooling efficiency of 27 % – an optimal result that does not require expensive investments. Slow blowing of the housing or adding only holes resulted in a decrease in the maximum heating temperature from 10 to 20 %, therefore, if the PET design allows the presence of holes, then it is necessary to rationally place them. Changing the shape of the back plate, heat-absorbing element, filling the housing with gas gave an efficiency decrease in the maximum temperature by 6–8 % compared to a closed housing with air.
The research results make it possible to choose the optimal option for reducing the heating temperature of the Langevin-type PET to increase its efficiency and long-term trouble-free operation.
Influence of bus service downtime in the transport interchange on the duration of inter-route transfer of passengers
Authors: Markevych Andrii , Vdovychenko Volodymyr , Ivanov Igor
Published: July 2021

The object of the study is the effect of the downtime of vehicles at stopping points on the duration of the route between passengers within the transport hub. As a controllable parameter that determines the conditions for synchronizing the presence of vehicles at stopping points and reproduces the characteristic effect on the weighted average time spent by passengers in transport hubs, the time of additional service downtime of vehicles is allocated. The simulation modeling and processing of the results obtained made it possible to establish the characteristic patterns of changes in the time spent by passengers in transport hubs for two types of routes with different volumes of passenger arrivals, the proportion of inter-route transfers and the interval of movement. It was found that for routes with scheduled arrivals more than 40 passengers and the specific gravity of inter-route transfers up to 45 %, the introduction of additional service downtime does not allow a positive effect on the duration of the stay of passengers in transport hubs. The implementation of service downtime is advisable for routes with an average volume of regular arrivals of passengers (up to 40 passengers) and a specific weight of inter-route transfers of more than 45 %. For such conditions, the regularities are described by a third-degree polynomial with the available characteristic period, which minimizes the function of the time spent by passengers. On the basis of the conducted experimental studies, it has been established that for routes with a specific gravity of a change from 45 % to 59 %, it is advisable to have a service downtime in the range of 1 minute up to 3 minutes, and for routes with a transfer rate of more than 59 % – within 2 minutes up to 5 minutes. The use of service downtime will increase the effectiveness of the synchronization of inter-route transfers in conditions of stochastic traffic and reduce the time spent by passengers in the transport interchange hub by 0.9–3.9 minutes (14–38 %) in comparison with the existing organization of interaction between the subjects of the route flow.
Analysis of the pectin extraction process at recycling of secondary material resources
Authors: Chabanova Oksana , Bondar Sergii , Kotliar Yevhenii , Nedobiychuk Tatiana , Verkhivker Yakiv
Published: July 2021

The object of research is the secondary material resources of processing plant and animal raw materials, namely fruit pomace and milk whey. One of the most problematic areas is that the waste of these industries has high rates of biological and chemical oxygen consumption of wastewater, which significantly impairs the operation of local and city treatment facilities. In addition, the parameters of extraction and determination of the quality indicators of the obtained product are not well defined. The processing of whey and pomace of fruit crops can reduce the environmental burden on the environment and increase the efficiency of technological processes through resource conservation and obtaining a surplus product. The problem is solved, in particular, by using the process of extracting plant waste using milk whey and the process of energy-saving membrane concentration.
In the course of the study, let’s use pectin-containing plant waste from juice production, namely watermelon, pumpkin, quince, beetroot, apple and a mixture of orange and tangerine pomace. The results obtained indicate that the process of extracting apple pomace with milk whey is promising, since the highest pectin content in the extract is established for apple pomace. The main amount of pectin substances passes into the extract starting from 75 minutes to 90 minutes. Extraction-hydrolysis for 2 hours at a temperature of 85 °C, pH=2–2.5 units determines the best results. Ultrafiltration of the obtained extract makes it possible to increase the pectin content up to 3.0 % with a protein content of more than 6.0 %. The membranes used in the experiment are characterized by high selectivity for protein and pectin. The fact is established that diafiltration makes it possible to effectively purify whey-pectin concentrates from ballast impurities with simultaneous enrichment of the concentrate with high-molecular components of whey. A technological scheme for the production of pectin-whey concentrate with high organoleptic and detoxification characteristics is proposed. The proposed technological process has a number of positive features, in particular, a high content of pectin substances, high value indicators, a significant reduction in the burden on the environment, economic benefits through energy conservation and obtaining a surplus product.
Transport modeling in the development of a complex transport scheme on the example of the city of Kyiv (Ukraine)
Authors: Humeniuk Oleksandra , Shapovalov Oleksij
Published: July 2021

The object of research is a complex transport scheme using the example of the city of Kyiv (Ukraine). The comprehensive transport scheme of the city of Kyiv provides for a variant design of the city’s transport system. In transport planning and design, for a qualitative assessment of planning decisions, predictive transport models of cities are most often used, which describe the macroscopic parameters of the traffic flow. The proposed options were tested on a transport model. The main task of this model is the modeling of transport correspondence, where the volume of traffic by public transport is about 80-90 % of the total volume of traffic. For this, a model was developed, with the help of which the level of loading of the main network, the volume of transport work, and the total number of passengers carried by public transport were analyzed. When choosing the optimal option, let’s took into account such parameters as the average speed of the traffic flow, general transport delays, and the total number of passengers transported by public transport. As well as the average distance of travel, the average time for the implementation of transport correspondence on public transport, the cost of unproductive loss of time by residents of the city, and so on.
Based on the results of transport modeling, the optimal option for the development of the city’s transport system was selected, which provides for the completion of the construction of existing road transport infrastructure facilities, the construction and development of the backbone network, systems outside the street rail transport, and optimization of the public transport route network. The complex transport scheme of the city of Kyiv, which was created using modern technologies in the field of transport modeling, allows to analyze and determine the effectiveness of the implementation of various measures for the development of the city’s transport infrastructure. Transport modeling has shown the feasibility of providing initial data for the feasibility study of investment projects, the arrangement of road transport infrastructure facilities, the improvement of traffic management schemes, the arrangement of new public transport routes.