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Innovative Utilization Possibilities of Industrial Wastes from Hungary as Construction Industrial Material
203-212Views:125The research results carried out at the University of Miskolc Faculty of Earth Science and Engineering in the Center of Excellence of Sustainable Natural Resource Management show that the physical and mechanical properties of the construction industrial products (strength, compactness) made of waste sources can be controlled reasonably by the appropriate processing technologies and under optimized circumstances and characteristics (particle size distribution, specific surface area). It was established that beside the chemical activation, the mechanical activation of solids is an effective tool for improving the product characteristics. However, this modifies the physical as well as structural, mineralogical properties of the raw materials, therefore its determination is of great importance.
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Temporal Changes of Pyrite Oxidation Rate in Bolivian Sulphidic Mining Wastes
194-202Views:94Since the 70's, when huge sulphidic open pits were developed, the acidic rock drainage (ARD) become the leader problem of the sulphidic mining industry. Although the recycling is an essential technology, it cannot cover the demand alone, thus mining activity needs to continue. Acidity in mine drainage commonly requires most of the attention, but the main problem is the caused elevated level of metal mobility and leaching, which are generated by the increased rates of sulphide weathering under acidic conditions. The Itos mine is a polymetallic vein deposit in Bolivia, had been mined for silver and tin until 1990, leaving behind much and huge tailings and mine waste heaps, where quite often the pyrite content exceeds 10 %. Serious ARD effects take place in the mine waste heaps. These processes can be well characterized with the pH 1 or 2 of the seepage water, which forms serious alteration in the waste itself and the neighbouring rocks. In three consecutive years, the pyrite oxidation rate was investigated on the same 7 samples by humidity cell test. 5-6 months pauses were left between the humidity cell test periods, which mimics the alternation of wet and dry periods, typical for the place. The results give much more information, than the oxidation rate in the individual test periods, showing the changes by time. This applied method gave good result to characterize the behaviour of the waste in long-term. The column test was complemented with mineralogical analyses, such as electron probe micro analysis. The mineralogical and column test analyses show, that the changes of the pyrite oxidation rate split the samples into three different groups, one where the oxidation rate decreases, second where it increases with time and the third where oxidation rate is maximal and stays stable for several years.
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Operational Feasibility Assessment of Geothermal Heat Harnessing Systems
46-53Views:170Renewable energy sources are now essential to establish sustainable development. This paper examines one kind of source the geothermal energy. For geothermal energy when combined with a heat pump COP can be used for evaluation. For solely geothermal sources different approach is needed thus in the paper, a new geothermal heat production coefficient is used to examine the operational feasibility. For the assessment, many hypothetical buildings were created to model their heat demands. Two types of calculation methods are used for heat demand calculation. Based on the results, the maximum depth of a geothermal borehole and economically critical qualitative coefficient was concluded.
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Reduction of Energy Use for Heating in Detached Houses using Passive Technics
64-76Views:146Reduction of energy use in buildings continue to be one of the most important goals in this sector. The aim of our research was to analyse the effects on the heating energy demand of passive technics. In the case of a detached house the energy savings using mass wall, Trombe-Michel wall and sunspace was determined. The calculations have been performed in the case of a building with average thermophysical characteristics and in the case of a building having similar geometry but its external building elements fulfilling the requirements of nearly zero energy buildings. It was proven, that some of the mentioned technics may lead to higher energy demand for heating, so a complex energy analysis has to be carried out before implementing them.
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Improvement of High Strength Automotive Steels Wettability Properties Using CO2 Laser Surface Treatment
422-427Views:168As a result of stricter environmental and safety standards, vehicle manufacturers have to reduce the weight of the vehicles, because 10% weight loss cause 8-10% reduction of fuel consumption. To reduce car’s weight and increase safety, vehicle manufacturers use high-strength steels. Further weight reduction can be achieved by using corresponding bonding technology (soldering, sticking) and optimizing these technologies can increase the strength of the joints. According to literature research, the improvement of interface properties has a large effect on bonding technologies. In order to improve interface properties, we can use multiple surface treatments. In our research we investigate the effects of CO2 laser surface treatment on high strength steels, because CO2 lasers are often used in the vehicle industry. In order to detect the effect of surface treatment, we investigate the wettability of the treated and untreated steels. In our research we measure the surface tension of treated and untreated steels. Our main goal is to improve wettability properties thus the bonding technology. In our research we used DP 600 high strength steel sheet with the thickness of 1 mm. We cut the steel sheet to 25mm wide and 55mm long workpieces. Before the surface treatment, the workpieces had to be cleaned and degreased using methanol. We searched for parameters that do not cause any visible changes on the surfaces. Among the parameters of the treatment we were able to change the output power of the laser. We used contact angle measurement to examine the wettability.
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Analysis of Smart Photovolatic Systems
67-75Views:107Nowadays more attention should be paid to the electric power generation wi th renewables. The photovoltaic systems have several benefits. But this systems power output could drastically drop by numerous external phenome. To avoid these, we introduce the so called “TIGO” power opti mizing system features and the monitoring of the deployed system on an existing building. We examine the produced energy for a given time period.
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Effects of TIG Reheating on Duplex Stainless Steel Weld Microstructure
295-302Views:164Duplex stainless steels (DSS) gaining their excellent mechanical properties and corrosion resistance due to their austenitic-ferritic microstructure, ideally in the same amount. However, to keep this ideal phase ratio during arc welding is very difficult. Generally, the arc welding processes will result in more ferritic microstructure in the weld metal and in the heat affected zone, due to the rapid cooling. The ferritic microstructure can cause chromiumnitride precipitation, because the nitrogen solubility in ferrite phase is very low below 700 °C. These chromiumnitride precipitations can cause loss of corrosion resistance and mechanical properties. However, during subsequent reheating, the chromium-nitrides can dissolve and act as a secondary austenite nucleation site in the ferritic microstructure. In our research we welded DSS specimen autogenously, with tungsten inert gas welding using pure argon and 94 % argon + 6 % nitrogen as shielding gasses. In the first case the sub-sequent solid-state reheating caused 20 % increase in the austenite fraction of the weld metal but with the use of mixed shielding gas only 5 % increase.
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Wind Energy Harnessing Options at Buildings
51-58Views:106Our goal was to develop a wind turbine system which could be applied in urban areas where the wind power has low potential, such as the cities in the “Alföld” region. The proposed system is able to harness more wind power at lower wind velocity than the commonly used ones, by using advantageo us properties of the flow in tunnels.
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Numerical Model Analysis of Myring–Savonius wind turbines
180-185Views:193Nowadays the importance of renewable energy is growing, and the utilization of the low wind energy potential is getting crucial. There are turbines with low and high tip speed ratio. Turbines with low tip speed ratio such as the Savonius wind turbine can generate adequate amount of torque at low wind velocities. These types of turbines are also called drag machines. The geometry of the blade can greatly influence the efficiency of the device. With Computational Fluid Dynamics (CFD) method, several optimizations can be done before the production. In our paper the Savonius wind turbine blade geometry was based on the so-called Myring equation. The primary objective of this paper was to increase the power coefficient by modelling the effect of the wind on the turbine blade. For the sake of simplicity, a 2D cross-sectional area was investigated in the simulation with ANSYS CFX 19.1.
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Calculations of Performance Losses for Automobile Vehicles
210-218Views:221Vehicle-energetic-models are used to analyze the performances and when a comprehensive structure is established even optimization could be done. For these kinds of models, the losses of the vehicles have to be known. These losses could significantly effect of the vehicle fuel consumption. From these losses the rolling resistance, drive elements and aerodynamic drag are discussed. This paper reviews some of the literatures that describes the calculation methods and gives us some idea about the degree of their value. Our further goals are to have an UpToDate loss coefficient dataset and calculation methods for further vehicle-energetic modelling.
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„Forradalmi” változások a menedzsment területén
1-15Views:161Development of the Science and practical application of the results created big changes in the nontradicional areas too. The „Health industry” was developed. The results of the physics, chemistry, biology and mikroelektronics etc. helped to develop some new methods of diagnosis, operation etc. The „money industry” was developed too. Our opinion is, that the most important cause of the economic crisis is a non regulated well of the „money industry”. The „knowledge industry” was developed too. The „knowledge industry” contains all level of teaching and Research + Development + Innovation. Our analyze shows that the Innovation is the most important factor of the economic Development of Society. The new scientific results created big changes in area of the Management. The „Management Science” was developed as an independent area. Some management specialists developed some management methods (eg. Value Analysis, Risk Management, TRIZ, Lean methods etc.) for efficient allocation of sources.
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Numerical Model Analysis of Natural Gas Combustion Burners
67-71Views:159Traditional power plants still the dominating power source for all the major industries and powerdemanding facilities, the most crucial facility for the whole plant operations is the industrial boiler which generatessteam, heating energy or electrical power. Boilers generate energy by combustion. The improvement of combustion efficiency could greatly influence the energy consumption and will make the boiler more efficient and cleaner (less emissions), that’s why it is important to understand the combustion and thermal flow behaviours inside the boiler. Beside experimental testing, computational work nowadays becoming more and more important due to lower cost and acceptable accuracy with minimum error. With numerical calculations method, the computational model created by a Computational Fluid Dynamics (CFD) software could reduce a lot of trial and error on experimental work. In this paper utilizing the ANSYS FLUENT 19.1 software to make crate the combustion model. The ratio of air to fuel mixture, the equivalency factor, mass flow rate of the mixture, velocity, mass fractions of the mixture components (fuel and air) and their temperatures will serve as the input parameter while the exhaust gase component mass fraction, temperature, mass flow and velocity will be monitored.
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Development of Analysis of Loss Sources of Vehicles
733-737Views:199Vehicle fuel consumption can be significantly influenced by various types of losses such as loss from bearing, aerodynamic drag and rolling drag. It is important to highlight that fuel consumption reduction can be only achieved when those losses are reduced that are induced during the operation.
The aim of our work group is to define the calculation method and the magnitude of the losses of the vehicles. These parameters are intended to be serve as input parameters for future energetic modelling of vehicles.
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A vállalati vagyon és a finanszírozás összefüggései a vagyonértékelés szempontrendszere szerint
69-79Views:220The availability for financial sources can be the key factor of competitiveness of enterprises. Under favourable conditions it can result in not only economic growth and conjunctural effects but indirectly it also has a positive influence on social level as well. In the first part of the article we make an overview on enterprise financing in both social and economic context and try to give an overall concept. In the second part we analyse the framework of financing, discuss the national and international specifications of financing, and finally, in the third part we analyse the background of enterprise financing based on the principles of asset appraisal.
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Wind Tunnel Making in Practise
19-24Views:113In this paper, we examined the low speed wind-tunnels. Our goal is to construct an open flow system windtunnel that can be utilized in our measurements. To make such a wind-tunnel we needed to build a prototype and calibrated with the help of measurements. Than we determined the flow at the area of measurement. Finally results of the measurements satisfied our expectations. Although there is still much more in development that we would like to do based on the newly gained experience.
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Ecological Balance of the Life Cycle of the Battery Electric Vehicles
137-141Views:111The economic and ecological assessment of propulsions for mobil applications is based on the analysis oft he entire chain of energy transformation. In this regard, the ecological assessment oft he automobile is complemented by emissions created during its production and ist recycling. The following paper aims at promoting the understandig oft he underlying subject matter and to make the reader aware of relevant aspects that must be looked for in similar assessments. Understanding the discussed contex makes it possible to objectively asses the contribution of BEVs (battery electric vehicles) to the enviroment. The assessment provides hints thet help discover problem areas and assist in deducting goals and measures fort he strategy of emobility.
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The Impact of Optical Character Recognition Artificial Intelligence on the Labour Market
9-16Views:374Because of present day information technology, there is neither need to plant complicated computers for more millions price if we would like to process and store big amounts of data, nor modelling them. The microprocessors and CPUs produced nowadays by that kind of technology and calculating capacity could not have been imagined 10 years before. We can store, process and display more and more data. In addition to this level of data processing capacity, programs and applications using machine learning are also gaining ground. During machine learning, biologically inspired simulations are performed by using artificial neural networks to able to solve any kind of problems that can be solved by computers. The development of information technology is causing rapid and radical changes in technology, which require not only the digital adaptation of users, but also the adaptation of certain employment policy and labour market solutions. Artificial intelligence can fundamentally question individual labour law relations: in addition to reducing the living workforce, it forces new employee competencies. This is also indicated by the Supiot report published in 1998, the basic assumption of which was that the social and economic regulatory model on which labour law is based is in crisis.
