International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The reasons of unsuccessful capital investments, which provide activity of industrial enterprises have been studied. It has been found out that to ensure industrial enterprises` sustainability, it is important to have the reserve of effective investments ideas . It has been determined that when planning industrial enterprises` activities it is important to take into account the probability of investment forecasts. The principal algorithms for actions in the process of planning to eliminate various types of deviations of actual results of investment activity from predicted ones have been proposed.

Theoretical approaches to the investment process` nature definition and the order of investment process` stages have been analyzed. The main trends of enterprises` investment process` introduction have been specified. Dynamics of enterprises` investment process` have been identified. The main features of investment cycle and its liaison with scientific and technical progress have been marked. It has been suggested to study industries` investment attractiveness as integral characteristic of separate economic fields regarding development perspectives, investment yield, and level of investment risks. It has been found out that certain industries` investment attractiveness is evaluated amid enterprise`s investment strategy`s development and field diversification of the investment portfolio.

The paper presents a thermodynamic analysis of gas turbine with real open cycle. Gas turbine operates in combined heat and power (CHP) system. Analysis is provided by using measured operating parameters of operating mediums (air and combustion gases) in all required operating points. Cumulative real turbine developed power amounts 78611.63 kW. In the whole gas turbine process, the highest losses occur in combustion chambers during the heat supply process and amounts 13689.24 kW. Turbine power losses are equal to 7976.22 kW, while the turbo-compressor power losses amounts 4774.24 kW. While taking into account all analyzed gas turbine components, the highest efficiency of 90.79% has turbine, followed by combustion chambers which efficiency is equal to 89.01%. Turbo-compressor efficiency amounts 88.59% and the whole gas turbine cycle has efficiency equal to 33.15%.

The paper presents a thermodynamic analysis of gas turbine with real open cycle. Gas turbine operates in combined heat and power (CHP) system. Analysis is provided by using measured operating parameters of operating mediums (air and combustion gases) in all required operating points. Cumulative real turbine developed power amounts 78611.63 kW. In the whole gas turbine process, the highest losses occur in combustion chambers during the heat supply process and amounts 13689.24 kW. Turbine power losses are equal to 7976.22 kW, while the turbo-compressor power losses amounts 4774.24 kW. While taking into account all analyzed gas turbine components, the highest efficiency of 90.79% has turbine, followed by combustion chambers which efficiency is equal to 89.01%. Turbo-compressor efficiency amounts 88.59% and the whole gas turbine cycle has efficiency equal to 33.15%.

The paper presents analysis of industrial gas turbine and its upgrade with heat regenerator. Based on a gas turbine operational data from a thermal power plant (base process) it was investigated advantages and disadvantages of heat regenerator implementation in the gas turbine process. Regenerator efficiencies were varied between 75% and 95%. Heat regenerator causes decrease of gas turbine fuel consumption up to 0.621 kg/s with a simultaneous increase in gas turbine process efficiency up to 10.52%. The main disadvantages of heat regenerator implementation are decrease in turbine cumulative and useful power along with decrease in the cumulative amount of heat released from the process.

The basics of applying the torque method for kinematic and power analysis of planetary gear trains are presented. With the help of the method, the speed ratios and efficiency of a real planetary gearbox are determined when operating on different gears (speeds).

We reported the investigation the effect of the optical and recombination losses in solar cells (SCs) based on nCdS(ZnSe, ZnS)/p-Cu2ZnSn(S,Se)4 heterojunctions with n-ITO(ZnO) frontal charge-collecting contacts on the internal (Qint), external (Qext) quantum yields, short-circuit current density (Jsc) and maximum efficiency (η) of solar cells.

It has been created an algorithm that tracks the stages of constructing an independent chemical power source. It has been given consideration to the selection and design of the composite components, as well as the solving of construction tacks. Attention is paid to the mechanical-dynamic and climatic tests, which are carried out in order to prove the working capacity for both of the components and the whole unit as a final product.

The paper considers the need for designing a dispenser for automated delivery of concentrated feed of small ruminants. Provides an analysis of the criteria for choosing optimal of auger conveyor parameters to ensure the required dosing accuracy for the specific purpose.

The model for ergonomic research includes an analysis and evaluation of a number of factors arising from:

1) the human factor (the trainer and the trainee) the organization and the results of his operations (assessment of effectiveness, efficiency, and satisfaction)

2) the level of the management and improvement of the electronic environment -hardware and software;

3) the conditions in the school premises, laboratories, auditoriums, offices and others. The paper presents results from a study with university teaching staff and students from UCTM using a methodology specifically designed for an ergonomic study of e-learning.

Evaluation of public investment efficiency in macroeconomic terms has increased the attention of the researchers in recent years. In this paper we concentrating on the evaluation of public investment based on the impact they have on the economic indicators and specifically the growth of private investment. Public investment at national and local level have an important role in economic growth and particularly public infrastructure contributes in increasing private investment, in the developing economies. In this regard, in our paper we get in study investment in public infrastructure and their impact on the number of private businesses in the municipality of Saranda. In the first part of this paper is treated the theoretical aspect of public investment, identification of economic indicators and evaluation of public investment on the basis of these indicators. In the second part we have treated methodology for collecting and processing data. For the realization of our paper, we are based on a statistical study of secondary data and to process them is using linear regression model. Data analysis represents the third part of the study, namely the correlation analysis of independent variables and the construction and analysis of linear regression equation, which expresses the connection of independent variables with the dependent variable. The ratio of public investment in infrastructure to public investment total, represent independent variable with the more important that we have included in our study, interest rates and the index of economic freedom represents independent explanatory variables, while number of business entities represents the dependent variable.

Construction of condenser plays important role for efficient operation of energy systems. In this system a heat pipe is utilized for heat transfer. The condensation part of the heat pipe is situated on top of the heating zone. The condenser is placed in the heating zone and is used for efficient heat transfer from one medium to another. The thermal oil is used as cooling medium in the condenser. This paper analyzes the effect of different operation condition of thermal oil to thermal performance. From the collected results it is obvious that the larger mass flow and higher temperature cause better thermal performance and lower pressure drop.