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Purpose. The study aims to investigate projects aimed at increasing the level of energy efficiency of public buildings using specialized software for dynamic energy modeling, DesignBuilder/EnergyPlus, for various levels of energy efficiency and integration of non-traditional and renewable energy sources. Methodology. In the process of researching the stated problem, the current regulatory framework of Ukraine, which describes and regulates approaches to assessing the energy efficiency of buildings and available software complexes, were analyzed. Proven specialized software for dynamic energy modeling of buildings (DesignBuilder/EnergyPlus) and non-traditional and renewable energy sources (PVSOL premium, TSOL) were used. Findings. During the research work, projects aimed at increasing the level of energy efficiency of a public building using different scenarios/levels of energy efficiency and integration of non-traditional and renewable energy sources were analyzed. The following scenarios were considered: actual, baseline, proposed, and enhanced proposed. For each scenario, indicators of final and primary energy consumption for heating, cooling, lighting, equipment, fans and pumps, hot water supply, as well as CO2 emissions and the potential for energy substitution from RES were analyzed. As a result of the implementation of measures provided for in the proposed scenario, the consumption of final energy can decrease by 58.6% compared to the baseline case, while the enhanced proposed scenario can increase these indicators to 62.6%. The coefficient of substitution of thermal energy by RES can be 22%, for electricity - 16% (enhanced proposed scenario). Scientific novelty. Dynamic energy modeling was used to calculate the level of energy efficiency of a public building for different scenarios, and modeling of the integration of non-traditional and renewable energy sources when replacing thermal and electrical energy was conducted. Practical value. As a result of the conducted research, the potential for saving final and primary energy, CO2 emissions when implementing various scenarios of projects aimed at increasing the level of energy efficiency and integrating RES was determined, allowing to make informed technical decisions during the comprehensive modernization of public buildings in Ukraine. [ABSTRACT FROM AUTHOR]

Due to the growing requirements for sustainable development and rational use of resources, especially in the context of the European Union's directives on energy efficiency in buildings, there is a growing attention to the development of solutions aimed at ensuring almost zero energy consumption in new public buildings. The article discusses the relevance of introducing energy-efficient technologies in public buildings in accordance with European energy efficiency standards. Particular emphasis is placed on the summer months, when intense solar radiation can lead to overheating of the premises, increased air conditioning costs, and negative impact on health and mood. In particular, the necessity of using passive methods, such as window shading, to reduce energy consumption and increase comfort in the summer months is dis-cussed. The object of the study is a preschool educational institution in Kyiv. The following factors are taken into ac-count in the study: heat gains from equipment, lighting, and people. Using Design-Builder software modeling, the energy demand for cooling and lighting energy consumption was estimated for the option with and without shading, including static shading and roller blinds. The results indicate that static shading is the most effective, and for the representative one reduces the energy consumption for cooling by 74.98 kWh compared to the option without shading, but at the same time leads to an increase in energy consumption for lighting by 4.63 kWh. It is noted that the installation of roller blinds on the inside may be the least efficient solution due to the increase in lighting costs and a slight decrease in energy consumption for cooling The impact of window orientation and shading location on efficiency is evaluated. In addition, the analysis of the effect of shading on radiant temperature shows that static shading contributes to lowering indoor temperatures, improving thermal comfort in summer. [ABSTRACT FROM AUTHOR]

The article discusses both a simpler dynamic model of a product market (referred to as the «web-like model») and a modified version of this model where sellers set the market price. These dynamic models are described using discrete firstorder difference equations and systems of difference equations. The study focuses on the importance of understanding dynamic market models for certain products, particularly the web and web-like market models with training, which are examined in the article. Based on certain assumptions (described further in the article), a Valsar interpretation of these models is provided: the market is regulated by an auctioneer who initially announces the product price, and then buyers and sellers execute agreements and communicate the results to the auctioneer in terms of supply and demand volumes. If the agreements are found to be imbalanced, the auctioneer adjusts the price in an attempt to restore market equilibrium. Final agreements are made once equilibrium is reached. The article considers cases where the initial point coincides or does not coincide with equilibrium, and analyzes the price and production volume trends in these scenarios. A formula is derived that determines the trajectory of price changes in the «spider model», indicating that the market price will fluctuate around the equilibrium price Additionally, a modifi cation of the simpler spider-like model is discussed, where sellers determine the market price by focusing on a weighted average value between demand and supply from the previous period. Similar to the web model, the equilibrium price is found. The article investigates the case when the initial point does not coincide with equilibrium and examines the trends of prices and production volumes in this scenario. Diff erent types of models are presented, and the properties of general solutions of diff erence equations and systems of diff erence equations that describe the web-like model and its modifi cation are analyzed [ABSTRACT FROM AUTHOR]

A retrospective review of the development of the theory and practical structures of electric machines with a three-degree-offreedom rotor (EMTR) at the Institute of Electrodynamics of the National Academy of Sciences of Ukraine. The applications of EMTR in surveillance, tracking and stabilization systems on moving objects are listed. The relevance of the development of such machines is shown. The disadvantages of the classical mathematical model of EMTR are noted and the need to develop a refined mathematical model due to the need to develop new technology, the emergence of new materials and electronic components, as well as the growth of computing capabilities. The two main known structures of EMTR are described and the advantages of the perspective structure chosen as the basic one are listed. The model of static three-dimensional magnetic field of EMTP and the associated dynamic model in the COMSOL Multiphisics environment are substantiated and constructed for the basic structure of EMTR. The connection between the magnetostatic problem and the rotor motion dynamics problem is ensured by the fact that the data of the calculated instantaneous characteristics are transmitted in the form of approximated dependences to the dynamic problem. In the mode of free rotation without losses, the dependences of the precession angle on time, amplitude and phase of the sinusoidal current of the control winding are calculated. High accuracy of observance of the direction of precession of the axis of the rotor at observance of the corresponding initial phase of sinusoidal current of a control winding is noted. The influence of rotation windings on the moment created by the control winding is investigated. References 7, figures 8, table 1. [ABSTRACT FROM AUTHOR]

In an atmosphere of market relations and the creation of a competitive environment, companies seeking to achieve competitive advantage are faced with the need to take into account consumer behavior in terms of economic exchange. The science of consumer behavior covers a wide range: it is the science of the processes that occur when individuals or groups choose and buy goods and services, use them and deprive them to meet their needs. The object of research is the dynamic behavior of consumers. The purpose of this study is to build a dynamic model that reflects the change in the actions of players depending on the change in their usefulness from the product over time in a limited market for material goods. The research methods of game theory, dynamic modeling, simulation modeling and scenario approach on the example of neoclassical model of equilibrium of goods in a limited market between a fixed number of players are used. The change of factors in time is taken into account. The problem of dynamic modeling is solved. A dynamic model was built that reflects the change in the actions of players depending on the change in their usefulness from the product over time in a limited market for material goods. With the help of the conducted research, several scenarios of consumer behavior were constructed. Namely, a symmetrical scenario, a scenario of cooperation of goals, and in the absence of cooperation. Compared, the efficiency of scenarios 1-2 is 92%, 2-3 is 68%, 1-3 is 63%. As you can see – partial cooperation on the goals of consumers reduces the utility rate slightly, but its total absence by more than a third. The adequacy of the use of this approach to modeling is analyzed and proved. It is established that not only players take part in the formation of the choice of a set of goods, due to changes in the usefulness of the product, but also the seller by changing the price. The seller, seeing the demand for his product, raises the price for it and vice versa, if none of the players bought k product, the seller is forced to reduce the price. This confirms the generally accepted economic theory of the balance of supply and demand in the market. But considered in terms of consumption by players. The behavior of players is compared, provided that the factors mentioned above are not taken into account, and their necessity in modeling is demonstrated. [ABSTRACT FROM AUTHOR]

Purpose of this study was to develop the main components of a model of an adaptive information system for predicting crop productivity. Methods. To conduct research on the establishment of the basic structural elements of an adaptive information model for predicting the productivity of basic crops used the method of constructing dynamic models. Results. A detailed analysis of conceptual approaches to the construction of mathematical agricultural models is carried out and the main advantages and disadvantages of modern analogues are established. It is determined that the adaptive information model is based solely on the needs of the plant and actually on the need to provide these needs with available resources in order to obtain consistently high yields with high quality indicators. The hardware and software complex must have a feedback relationship between its basic structural elements, because it significantly improves the accuracy of predicting plant productivity. Data based on the operation of certain mechanisms or indicators of weather conditions and their forecasts are used for decision making, however, if they are substantially changed, decisions about individual technology elements are reviewed. The software should be related to the economic part and should take into account market conditions and forecast data when making recommendations. In the case of low purchase prices for products, we recommend that certain agrotechnical operations (say vegetation feeding) be applied or not, in the case of significant change in growing conditions - when the application of these agro-measures will be ineffective due to the negative effects of drought, etc. Conclusions. Adaptive information system for forecasting productivity in the technological process of growing crops is formed on the basis of a model consisting of three modules of characteristics – the resultant and two components. At each subsequent stage of implementation of the model, the resulting feature becomes component, with the maximum contribution to the resulting feature of the next module.

The most common method of treating of the congenital funnelshaped chest is thoracoplasty method by D. Nuss. During this surgery, a significant mechanical effect is created on the ribs, sternum, spinal column, which act instantly and continuously for a long time and create new biomechanical conditions for the «chest -- rib -- spine» system. Objective. To construct a functional model of the chest with a spinal column, which takes into account the movements in the costal-vertebral joints, it allows modeling the funnel-shaped deformation in conditions close to the reality, its operative correction, predicting the results and choosing the optimal parameters of thoracoplasty. Methods. Normal and funnel-shaped chest models based on the articular connection of the ribs to the spine were created using SolidWorks. The main calculations were made using the ANSYS program. To estimate the stress-strain state (SSS), stresses are selected by Mises. Results. The created dynamic mathematical model of the chest makes it possible to conduct a reliable analysis of the biomechanical interaction of the plate with the chest, to analyze the stress-strain state of the constructed models in the norm, with and without taking into account the movements in the costal-vertebral joints. In addition, it allows to simulate the operation by D. Nuss and to study the biomechanical changes in conditions close to reality, occurring in the «chest -- rib -- spine» system, to determine the areas of maximum loads and safety boundaries. Conclusions. The reproduction of articular ribs rotation in the dynamic model changes the picture of the SSS distribution. In the case of modeling the correction of funnel-shaped deformation of the chest by the method by D. Nuss, the largest zone of stress concentration was found on the outer posterior surface of the sixth pair of ribs. The most tense vertebrae were ThV-- ThVI, but the maximum values did not exceed the permissible values. In the case of a lower plate conduction, the correction is achieved with better SSS values in the higher elements of the «chest -- ribs -- spine» system. [ABSTRACT FROM AUTHOR]

The methodology of political conflict analysis is studied in the context of using both general and special methods. Emphasis is placed on the information challenges of the modern political conflicts, due to the growing information impact on the course of political processes. Emphasis is placed on the need to use interdisciplinary research methods in response to growing information challenges. The essence of methods of content and event analysis, clustering and modeling of dynamic systems, swotand gap analysis, as well as game theory in the study of modern political processes is revealed. Examples and arguments on the need to use specialized interdisciplinary methods for qualitative and comprehensive analysis of the causes, motives of participants, the course of political conflicts and scenarios for their resolution are given. [ABSTRACT FROM AUTHOR]

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Purpose. Research of the problems in different types of energy efficiency projects in public, residential and manufacturing facilities buildings that are or can be made by students of energy specialties with using dynamic energy modeling software for buildings and renewable energy sources. Methods. In the process of researching the mentioned problems are considered examples of works using: mathematical modeling of heat transfer processes, energy balances and modeling software. The current Ukrainian legal base, which describes and regulates approaches for energy efficiency assessment of buildings, is analyzed also. Results. In the course of the research typical projects for improving of the energy efficiency level of public, residential and manufacturing facilities buildings are considered, conducted by the students of energy specialties with using software packages such as RETScreen, EnergyPlus, DesignBuilder, etc., the technical potential of the mentioned software packages are analyzed, the methods of processing of input data for some programs are considered, the main characteristics, advantages, disadvantages and difficulties that students face in making of energy modeling and analysis of results are presented. Scientific novelty. The existing experience of the energy modeling of buildings by students and the analysis of certain difficulties that arise in modeling is systematized, which allows to optimize the whole process of research of energy efficiency of buildings. The practical significance. As a result of the stated research the potential of using different software complexes for student training in energy modeling of buildings and analysis of the criteria of the energy efficiency of buildings in Ukraine was determined. [ABSTRACT FROM AUTHOR]

Purpose. Development and analysis of mathematical model of oscillation processes that occur during material processing in centrifugal drum washing machines, determination of absence conditions of contact deformations of working bodies and body of centrifugal machine. Methodology. The methods of mathematical and dynamic modeling of electromechanical systems using specialized software are used. Result of the study is the development and improvement of a dynamic model for the study of physical processes occurring in the oscillating suspension system of drum machines and centrifuges. A mathematical model (six degrees of freedom) was developed to describe the plane motion of the suspension of a drum machine. The conditions that are responsible for maintaining contact between the left and right body supports with the base are defined. The condition responsible for maintaining the friction bond between the housing and the base (floor) is also highlighted. Additionally, a check was made for the absence of collisions and shocks of the protruding elements of the spring-loaded tank counterbalance system with the lateral, lower and upper walls of the center of the centrifugal drum washer. Scientific novelty. The analytical expressions that determine the dependencies of forces affecting the working bodies of centrifugal automatic washing machines are obtained in the work. The data analysis software was used to check whether the friction connection between the base of the case and the floor is broken, and whether the legs of the case are detached from the floor. Practical significance. The results of the research can be used to develop designs of centrifugal machines of the same type for different industries or domestic applications. [ABSTRACT FROM AUTHOR]

Copyright of Financial & Credit Activity: Problems of Theory & Practice is the property of University of Banking of the National Bank of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Urgency of the research. The sphere of food provision of Ukraine represents a multidimensional space, the three sides of which the government-producer-consumer are constitute - the system triad. Systemic unity is explained by the integration of its components, since their stakeholders can play a simultaneously or sequentially double role in the market interaction process. This leads to a weakening of their interdependence, exacerbating the co-evolutionary imbalance of its constituents, which forms the preconditions for polarizing the interaction stakeholders of the market sides. Target setting. Reducing the density of economic ties between stakeholders reduces the sustainability of the food provision sphere, posing threats to food security. They are preceded by an imbalance of the stakeholders' economic interests, which necessitates the elaboration of a methodology for reconciling them. Actual scientific researches and issues analysis. Today, the opinions of scientists exploring the rationalization of market interaction are split in half. Some of them try to outline the conditions of optimal format of relations between market interactions' stakeholders in the, while others are focused on the design of harmonious markets. Uninvestigated parts of general matters defining. The results of scientific research are interpreted in the simulation or economic-mathematical models form. The research objective. To propose an algorithm for the synthesis of traditional methods with new knowledge and to construct of a harmonious food market dynamic model. The statement of basic materials. Given the macro-scale of scientific research, it is rational to combine optimization methods with simulation models. Cognitive maps should be built on the basis of multi-vector optimization, which will allow to establish causality of the economic processes and their effects. The whipping of the vector criterion into a global one should be supplemented with the simulation model Leebikh "barrel", which will make it possible to single out the most depressed ones. It is advisable to project a fair compromise on a systemic triad, combining it with the method of successive concessions. Conclusions. The algorithm of composing the scientific cognition methods allowed us to design a dynamic model of a harmonious market in the form of a triple integrated helix, capable of taking into account the co-evolution of its three sides. [ABSTRACT FROM AUTHOR]

Purpose. Generalization of dynamic researches of knitting mechanism of hosiery machinery for example of knitting needles for obtaining theoretical information on the spectrum of their loads, which are used in further calculations for fatigue longevity in deterministic and probabilistic aspects. Methodology. Is used the methods for describing and analyzing complex technical systems for audit of a set of dynamic calculations in the context of interaction knitting needles with various cams. Findings. Is considered the possibility of using dynamic models of needle interaction in the knitting system at the design stage for obtain a quantitative picture of their loading and determine the zone of rational design parameters of the system for a given fatigue longevity of needles. Originality. Is consists in subsequent development of theory and methodology for mathematical maintenance for the design of high-speed hosiery machinery. Is applies for complex assessment and analysis of the refined load spectrum for determination of longevity of knitting needles by the criterion of fatigue strength. Practical value. Are presented information that promotes a comprehensive approach to the analytical definition of the loads spectrum, which increases the quality and efficiency of project solutions for ensuring a given fatigue longevity of needles in a wide range of speed regimes of the hosiery machinery. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Economy is the property of Research Centre for Industrial Developmen Problems of Nas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The main aim of the work is development of the dynamic model with time-varying parameters. Empirical data is used to determine parameters of the model. Existing dynamic mathematical models of batch processes are thoroughly studied and analyzed. It is established that the usage of a time-varying aperiodic link significantly simplifies the calculation procedure that occurs in case of applying formal dynamic models. The advantage of applying the developed model with the time-varying aperiodic link compared to the other considered models is shown. As a result, the number of identified parameters is reduced and the sufficient accuracy of the model is provided due to the usage of methods based on the empirical data processing. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mechanical Engineering the National Technical University of Ukraine 'Kyiv Polytechnic Institute' is the property of National Technical University of Ukraine KPI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose. Working out of mathematical models of the speed-controlled induction electric drives ensuring joint consideration of transformers, motors and loadings, and also matching reducers and transformers, both in static, and in dynamic regimes for the analysis of their operating characteristics. Methodology. At mathematical modelling are considered functional, mass, dimensional and cost indexes of reducers and transformers that allows observing engineering and economic aspects of speed-controlled induction electric drives. The mathematical models used for examination of the transitive electromagnetic and electromechanical processes, are grounded on systems of nonlinear differential equations with nonlinear coefficients (parameters of equivalent circuits of motors), varying in each operating point, including owing to appearances of saturation of magnetic system and current displacement in a winding of a rotor of an induction motor. For the purpose of raise of level of adequacy of models a magnetic circuit iron, additional and mechanical losses are considered. Results. Modelling of the several speed- controlled induction electric drives, different by components, but working on a loading equal on character, magnitude and a demanded control range is executed. At use of characteristic families including mechanical, at various parameters of regulating on which performances of the load mechanism are superimposed, the adjusting characteristics representing dependences of a modification of electrical, energy and thermal magnitudes from an angular speed of motors are gained. Originality. The offered complex models of speed-controlled induction electric drives with matching reducers and transformers, give the chance to realize well-founded sampling of components of drives. They also can be used as the design models by working out of speed-controlled induction motors. Practical value. Operating characteristics of various speed-controlled induction electric drives are observed and depending on the chosen measure including measure of cost of losses of active energy, sampling of the best alternative of the drive is realized. [ABSTRACT FROM AUTHOR]

A dynamic model to investigate the electromechanical processes in multimass vibration devices with electromagnetic drive is proposed. The model is based on the interpolation of the results of magnetostatics numerical solution by finite element method and the differential equations describing the dynamics of electromagnetic and mechanical processes. The model takes into account the nonlinearity of the steel B-H curve, three-dimensional distribution of the magnetic field, leakage fluxes, eddy currents, hysteresis, oscillating masses elastic interaction, the viscous friction force, the mutual influence of electromagnetic and mechanical processes. The experimental investigation results confirm the adequacy of the dynamic model. [ABSTRACT FROM AUTHOR]

This paper considers general principles for constructing and investigating mathematical models of natural resources flow distribution along the energy network. Based on classical and generalized conservation laws we construct the complex of dynamic models for flow distribution in networks taking into account the ability to create reserves of energy resources and the uncertainty of information objectively inherent in large power systems. Also, we exemplify the issues of water traffic control in the channels of water irrigation systems and gas pipelines. The proposed approach is the most useful for long-term planning, but can be used in cases of the operational control of flow distribution in distribution systems subject to periodic measurement and specification of certain network parameters. [ABSTRACT FROM AUTHOR]