Danut Tokar - Academia.edu (original) (raw)

Papers by Danut Tokar

Revista Romana de Inginerie Civila/Romanian Journal of Civil Engineering, 2020

This paper presents the integrated photovoltaic panels (BIPV) in buildings. They have as their pr... more This paper presents the integrated photovoltaic panels (BIPV) in buildings. They have as their primary purpose the generation of electricity used as an energy resource for buildings or the distribution of energy in the national grid. These systems can provide cost savings on materials and electricity, reduce pollution and add to the architectural aspect of the building. Although these can be added to a structure as functional elements, the biggest challenge for these systems is their inclusion in the initial design of the building.

Economic Science for Rural Development, 2018

Among the issues of the public services of economic interest, the water supply of urban and rural... more Among the issues of the public services of economic interest, the water supply of urban and rural localities (areas where investment in this sector is limited) is of particular importance in maintaining social cohesion, raising the quality of life and ensuring sustainable development. The purpose of this analysis is to propose solutions for insuring and improving the water supply of isolated consumers in mountain rural areas, which is why a mountain tourist mountain hut has been chosen for this study. In this context, this paper addresses as a solution for the sustainable management of natural resources the use of rainwater. It is proposed to redesign the sanitary installation so that plumbing items that do not require drinking water can be fed through a separate installation. The proposed solutions are based on a comparative analysis of the microbiological parameters and the quality indicators between precipitation water and spring water with which the mountain hut is fed by an individual system. It is concluded that the recovery, storage and the use of the rainwater plays an important role in ensuring the supply of drinking water for the mountain cabin during periods when the water flow of the spring is low (in winter) and it contributes significantly to saving the freshwater resource in the area where the mountain hut is located.

5th International Multidisciplinary Scientific Conferences on SOCIAL SCIENCES and ARTS SGEM2018, Modern Science, 2018

ADRIANA TOKAR1*, ARINA NEGOITESCU2, MARIUS ADAM1, DANUT TOKAR2 1University Politehnica from Timis... more ADRIANA TOKAR1*, ARINA NEGOITESCU2, MARIUS ADAM1, DANUT TOKAR2 1University Politehnica from Timisoara, Civil Engineering Faculty, Department of Civil Engineering and Installations, 2 Traian Lalescu Str., 300223, Timisoara, Romania 2 University Politehnica from Timisoara, Faculty of Mechanical Engineering, Department of Mechanical Machinery, Equipment and Transport, 1 Mihai Viteazu Blv., 300222, Timisoara, Romania

IOP Conference Series: Materials Science and Engineering, 2021

Even though the science and technology in the field of energy production for buildings has reache... more Even though the science and technology in the field of energy production for buildings has reached an advanced stage of development, there is still a considerable part of the population who do not have access to electricity. Currently, renewable energy (Solar, Wind, Geothermal, Hydro, Wave energy, Biogas), are considered sources that will meet future energy requirements, but have geographical limitations, are not available throughout the territory and are difficult to integrate into energy systems due to of the unpredictable character, their functioning being determined by the weather conditions. Also, the power and efficiency of renewable energy systems are still limited. Given that gravity (the fundamental forces of nature) is available everywhere, regardless of the climatic conditions, it represents an inexhaustible source of energy. In the context of apocalyptic scenarios or cyberattacks on energy systems, gravitational electrical systems can offer solutions for restoring electr...

IOP Conference Series: Materials Science and Engineering, 2021

This paper presents the mathematical model and simulation of a thermal system for heating and sup... more This paper presents the mathematical model and simulation of a thermal system for heating and supplying hot water to industrial or residential consumers consisting of a heat exchanger on the heating circuit and a heat exchanger provided with an accumulation tank on the domestic hot water circuit, this scheme is generally adopted in the industrial thermal points and increasingly in module-type thermal points for residential consumers. The mathematical model is based on the mathematical equations describing this system and developed using the MATLAB - Simulink program. Thus, as a result of the simulations, we can see the evolutions in time of the water temperatures on the heating circuit and the domestic hot water circuit, as well as the quantity of heat delivered by them.

IOP Conference Series: Materials Science and Engineering, 2021

A better understanding of leak related effects has implications for pipe rehabilitation, system e... more A better understanding of leak related effects has implications for pipe rehabilitation, system economics, customer disruption, and environmental sustainability. Reducing leakage be a result of a well-suited preventive maintenance program. The purpose of this study is to inspect approximately 10% of the runouts (branch pipes) between the plumbing fixtures and the risers to estimate the extent of serious corrosion of the runouts that may cause leaks in the future. For collecting the site data for our study, we visited the building and investigated piping through 57 different access openings in 31 randomly selected apartments. These apartments were selected to allow observation of a variety of risers at varying elevations. We observed in about 20% of the runouts inspected, the remaining thickness of the steel pipe was less than 60% in the areas that we could access. The runouts are in danger of developing leaks. Because of the high potential cost of leaks and the possibility of that 2...

IOP Conference Series: Materials Science and Engineering, 2021

This paper is focused on a study between different heating systems commonly used in industrial in... more This paper is focused on a study between different heating systems commonly used in industrial installations. Industrial heating systems generally raise difficult problems in choosing the most economical system. If several solutions technically meet the requirements of the indoor climate, in terms of energy efficiency we must focus on the optimal solution. The study was conducted to choose the optimal heating solution for an industrial hall, from the point of view of evaluating the efficiency of the installation of an exhaust gas recirculation equipment. The heating of industrial premises generally raises difficult problems due to the diversity of the types of buildings encountered, the variety of activities carried out and the need to choose the most economical system, both in terms of investment and operation. The radiation heating system using natural gas offers the solution of this problem, in situations where the classic heating systems (hot air heating or static bodies) cannot...

The presence of harmonics in the electrical installations and in the electrical systems of power ... more The presence of harmonics in the electrical installations and in the electrical systems of power supply is due to the currents. Measuring the values of harmonic voltages and currents is very important, and the determined values must be explicitly specified as values of voltage and current. At present, the types of equipment that produce harmonics have increased so that careful consideration of the harmonics and their effects must be given. For this reason, the article presents an analysis of the electrical quantities related to the supply system for sterile speakers inside the Emergency Clinical Hospital for Children "Louis Țurcanu" in Timisoara. The measurements directly measured by the recording equipment are the currents and voltages, in instantaneous values, on the three phases of the input in the supply panel. The monitored sizes were transferred to the processing-evaluation-recording unit which provided information for evaluating the THD distortion factor.

20th International Scientific Conference "Economic Science for Rural Development 2019". Integrated and sustainable regional development. Marketing and sustainable consumption., May 8, 2019

The article addresses the concept of sustainable energy development and the need to promote it, p... more The article addresses the concept of sustainable energy development and the need to promote it, particularly in economically disadvantaged regions, to find optimal long-term solutions to conventional energy production. One of the sustainable development solutions of economically disadvantaged regions is the integration of renewable energy sources (RES) into existing energy systems. The proposed integration solutions were based on the analysis of the energy potential of a region in western Romania, a region economically disadvantaged by the closure of the mining and the thermal power plant (CET) existing in the area. The amount of energy required for installation to cover the electricity consumption of the population in the region was the basis for interpretations on the choice of RES solutions. The integration of RES in the context of sustainable development ensures the following: socioeconomic development of the regions, access to energy, energy security, reduction of polluting emissions and reduction of negative health effects. The purpose of this article is to bring to the attention of the local government the importance of the energy potential of the area and the opportunity for the economic recovery of the whole region, while reducing GHG emissions

IOP Conference Series: Materials Science and Engineering, 2019

Exceeding intermitence and the stochastic character associated with most renewable energy sources... more Exceeding intermitence and the stochastic character associated with most renewable energy sources in order to maintain the balance between generation and consumption require the most efficient energy storage methods. This balance is important to maintain the quality of the power supply by adjusting the frequency and voltage of the grid. Storage is the capture of the energy produced at a given time for later use. It is known that electricity cannot be stored directly unless it is stored in condenser batteries or in superconducting coils. Other methods of electricity storage presuppose the conversion of these into other forms of energy: mechanical storage, electrochemical storage. The optimization of RES operation and, implicitly, of the energy system implies the choice of a suitable conversion / storage system that must take into account a number of factors, such as: capacity and minimum storage time, loading and unloading conditions, minimum number of cycles download loading, power ...

Revista Romana de Inginerie Civila/Romanian Journal of Civil Engineering, 2020

This paper presents the integrated photovoltaic panels (BIPV) in buildings. They have as their pr... more This paper presents the integrated photovoltaic panels (BIPV) in buildings. They have as their primary purpose the generation of electricity used as an energy resource for buildings or the distribution of energy in the national grid. These systems can provide cost savings on materials and electricity, reduce pollution and add to the architectural aspect of the building. Although these can be added to a structure as functional elements, the biggest challenge for these systems is their inclusion in the initial design of the building.

Economic Science for Rural Development, 2018

Among the issues of the public services of economic interest, the water supply of urban and rural... more Among the issues of the public services of economic interest, the water supply of urban and rural localities (areas where investment in this sector is limited) is of particular importance in maintaining social cohesion, raising the quality of life and ensuring sustainable development. The purpose of this analysis is to propose solutions for insuring and improving the water supply of isolated consumers in mountain rural areas, which is why a mountain tourist mountain hut has been chosen for this study. In this context, this paper addresses as a solution for the sustainable management of natural resources the use of rainwater. It is proposed to redesign the sanitary installation so that plumbing items that do not require drinking water can be fed through a separate installation. The proposed solutions are based on a comparative analysis of the microbiological parameters and the quality indicators between precipitation water and spring water with which the mountain hut is fed by an individual system. It is concluded that the recovery, storage and the use of the rainwater plays an important role in ensuring the supply of drinking water for the mountain cabin during periods when the water flow of the spring is low (in winter) and it contributes significantly to saving the freshwater resource in the area where the mountain hut is located.

5th International Multidisciplinary Scientific Conferences on SOCIAL SCIENCES and ARTS SGEM2018, Modern Science, 2018

ADRIANA TOKAR1*, ARINA NEGOITESCU2, MARIUS ADAM1, DANUT TOKAR2 1University Politehnica from Timis... more ADRIANA TOKAR1*, ARINA NEGOITESCU2, MARIUS ADAM1, DANUT TOKAR2 1University Politehnica from Timisoara, Civil Engineering Faculty, Department of Civil Engineering and Installations, 2 Traian Lalescu Str., 300223, Timisoara, Romania 2 University Politehnica from Timisoara, Faculty of Mechanical Engineering, Department of Mechanical Machinery, Equipment and Transport, 1 Mihai Viteazu Blv., 300222, Timisoara, Romania

IOP Conference Series: Materials Science and Engineering, 2021

Even though the science and technology in the field of energy production for buildings has reache... more Even though the science and technology in the field of energy production for buildings has reached an advanced stage of development, there is still a considerable part of the population who do not have access to electricity. Currently, renewable energy (Solar, Wind, Geothermal, Hydro, Wave energy, Biogas), are considered sources that will meet future energy requirements, but have geographical limitations, are not available throughout the territory and are difficult to integrate into energy systems due to of the unpredictable character, their functioning being determined by the weather conditions. Also, the power and efficiency of renewable energy systems are still limited. Given that gravity (the fundamental forces of nature) is available everywhere, regardless of the climatic conditions, it represents an inexhaustible source of energy. In the context of apocalyptic scenarios or cyberattacks on energy systems, gravitational electrical systems can offer solutions for restoring electr...

IOP Conference Series: Materials Science and Engineering, 2021

This paper presents the mathematical model and simulation of a thermal system for heating and sup... more This paper presents the mathematical model and simulation of a thermal system for heating and supplying hot water to industrial or residential consumers consisting of a heat exchanger on the heating circuit and a heat exchanger provided with an accumulation tank on the domestic hot water circuit, this scheme is generally adopted in the industrial thermal points and increasingly in module-type thermal points for residential consumers. The mathematical model is based on the mathematical equations describing this system and developed using the MATLAB - Simulink program. Thus, as a result of the simulations, we can see the evolutions in time of the water temperatures on the heating circuit and the domestic hot water circuit, as well as the quantity of heat delivered by them.

IOP Conference Series: Materials Science and Engineering, 2021

A better understanding of leak related effects has implications for pipe rehabilitation, system e... more A better understanding of leak related effects has implications for pipe rehabilitation, system economics, customer disruption, and environmental sustainability. Reducing leakage be a result of a well-suited preventive maintenance program. The purpose of this study is to inspect approximately 10% of the runouts (branch pipes) between the plumbing fixtures and the risers to estimate the extent of serious corrosion of the runouts that may cause leaks in the future. For collecting the site data for our study, we visited the building and investigated piping through 57 different access openings in 31 randomly selected apartments. These apartments were selected to allow observation of a variety of risers at varying elevations. We observed in about 20% of the runouts inspected, the remaining thickness of the steel pipe was less than 60% in the areas that we could access. The runouts are in danger of developing leaks. Because of the high potential cost of leaks and the possibility of that 2...

IOP Conference Series: Materials Science and Engineering, 2021

This paper is focused on a study between different heating systems commonly used in industrial in... more This paper is focused on a study between different heating systems commonly used in industrial installations. Industrial heating systems generally raise difficult problems in choosing the most economical system. If several solutions technically meet the requirements of the indoor climate, in terms of energy efficiency we must focus on the optimal solution. The study was conducted to choose the optimal heating solution for an industrial hall, from the point of view of evaluating the efficiency of the installation of an exhaust gas recirculation equipment. The heating of industrial premises generally raises difficult problems due to the diversity of the types of buildings encountered, the variety of activities carried out and the need to choose the most economical system, both in terms of investment and operation. The radiation heating system using natural gas offers the solution of this problem, in situations where the classic heating systems (hot air heating or static bodies) cannot...

The presence of harmonics in the electrical installations and in the electrical systems of power ... more The presence of harmonics in the electrical installations and in the electrical systems of power supply is due to the currents. Measuring the values of harmonic voltages and currents is very important, and the determined values must be explicitly specified as values of voltage and current. At present, the types of equipment that produce harmonics have increased so that careful consideration of the harmonics and their effects must be given. For this reason, the article presents an analysis of the electrical quantities related to the supply system for sterile speakers inside the Emergency Clinical Hospital for Children "Louis Țurcanu" in Timisoara. The measurements directly measured by the recording equipment are the currents and voltages, in instantaneous values, on the three phases of the input in the supply panel. The monitored sizes were transferred to the processing-evaluation-recording unit which provided information for evaluating the THD distortion factor.

20th International Scientific Conference "Economic Science for Rural Development 2019". Integrated and sustainable regional development. Marketing and sustainable consumption., May 8, 2019

The article addresses the concept of sustainable energy development and the need to promote it, p... more The article addresses the concept of sustainable energy development and the need to promote it, particularly in economically disadvantaged regions, to find optimal long-term solutions to conventional energy production. One of the sustainable development solutions of economically disadvantaged regions is the integration of renewable energy sources (RES) into existing energy systems. The proposed integration solutions were based on the analysis of the energy potential of a region in western Romania, a region economically disadvantaged by the closure of the mining and the thermal power plant (CET) existing in the area. The amount of energy required for installation to cover the electricity consumption of the population in the region was the basis for interpretations on the choice of RES solutions. The integration of RES in the context of sustainable development ensures the following: socioeconomic development of the regions, access to energy, energy security, reduction of polluting emissions and reduction of negative health effects. The purpose of this article is to bring to the attention of the local government the importance of the energy potential of the area and the opportunity for the economic recovery of the whole region, while reducing GHG emissions

IOP Conference Series: Materials Science and Engineering, 2019

Exceeding intermitence and the stochastic character associated with most renewable energy sources... more Exceeding intermitence and the stochastic character associated with most renewable energy sources in order to maintain the balance between generation and consumption require the most efficient energy storage methods. This balance is important to maintain the quality of the power supply by adjusting the frequency and voltage of the grid. Storage is the capture of the energy produced at a given time for later use. It is known that electricity cannot be stored directly unless it is stored in condenser batteries or in superconducting coils. Other methods of electricity storage presuppose the conversion of these into other forms of energy: mechanical storage, electrochemical storage. The optimization of RES operation and, implicitly, of the energy system implies the choice of a suitable conversion / storage system that must take into account a number of factors, such as: capacity and minimum storage time, loading and unloading conditions, minimum number of cycles download loading, power ...