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Formation of Oxide Layers with Femtosecond Laser on Steel Surfaces for Color Marking
174-178Views:215With the appearance of ultrashort pulse lasers, the researchers have begun working on various laser marking technology. Atmospheric heating and ablation of a surface induce laser coloration of metal surfaces. However, their application is still problematic today in the industry. With the appearance of femtosecond pulse lasers, a new concept became available for color marking. This concept is based on the formation of laser-induced periodic surface structures (LIPSS) on metal surfaces. The purpose of this article is to summarize the literature of laser color marking with ultrashort pulse lasers.
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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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The Pressure Characteristics of the Released Gases from Sand Cores
73-79Views:157The core packages used for the production of castings are generally made from cores of different quality (no- bake phenol, HB-phenol, and HB-furan) and resin quantity, to meet the various requirements for the casting. In our research, the effect of the amount of resin on the pressure of the gases evolved from the cores was investigated. Experiments have shown that increasing the amount of resin has a different effect on different binder systems.
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Examination of Infrared Tomato Drying
303-309Views:101Tomato is a highly perishable food, thus preservation is required to meet the continuous market demand compared to the unbalanced yearly production peak. The aim of this paper is to show a detailed insight into infraradiation based drying process. Furthermore, to widen the possible usage range of a well-known approximation method for describing the temporal moisture variation in function of process parameters. The mass decrease of tomato slices was examined, in function of specific radiation power, heat source and sample distance, in forced and natural airflow. Based on the results dimensionless moisture ratio change over time was fitted as an exponential function, which may be used in industrial drying process optimization.
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Modeling the Thermal Behavior of Permanent Magnet Synchronous Motors
466-477Views:155The aim of this study is to present a thermal analysis of a permanent magnet synchronous machine based on finite element method. The developed model can be used to predict temperature distribution inside the studied motor during the rated operation. Electromagnetic computation is carried out with the aid of two 2D finite-element (FE) simulations on the cross-section of the PM motor. To analyse the process of heat transfer in an electrical machine, empirical correlations are used to describe the convective heat transfer from the different surfaces of the PM motor. The heat transfer coefficient is determined using dimensionless numbers and Nusselt number. After the loss calculation, the temperatures of the machine are calculated by using 3D finite element method. The results obtained by the model are compared with experimental results from testing the prototype electric motor.
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Analysis of Vibration During Turning Process of Different Materials
200-205Views:132In this article, we would like to introduce the problems caused by vibrations in case of polymer turning processes. Nowadays there is a lot of research in this topic, to avoid the unnecessary phenomena of vibrations. The two most common methods are the Spindle Speed Variation (SSV), and the Vibration Assisted Machining (VAM). In case of SSV, the CNC machine can increase and decrease the speed of spindle continuously during turning which can significantly reduce the effects of chatter. This method is beneficial for longer workpieces when there is not any support except the chuck. Vibration-assisted machining can be used to minimise the problems caused by vibrations. VAM combines precision machining with small-amplitude tool vibration to improve the fabrication process. It has been applied to some processes ranging from turning, drilling to grinding. Based on the enumerated above we made some trial measurements about the basic vibrations of the turning tool shank. The tests were done on an NCT EUROturn-12B CNC machine which can found in the workshop of our institute. The tested material was Polyamide 6 because this is the most commonly used polymer in the industry. In the future, we would like to test some other basic and composite polymer materials too. The equipment was served by a specialist from SPM Budapest Kft. With these tests, our goal was to make sure that the equipment and the measuring setup are suitable for our future research.
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What Fields Can Technology Management be Applied to?
637-645Views:183There are two types of technology management definitions. The narrow ones only refer to business organizations, the broad ones refer to any kind of organizations, including non-profit and governmental organizations. By using the narrow definitions, the interest of the non-profit and governmental organizations cannot be attracted, they could think that they do not need to deal with technology management, but in reality they obviously use it. To avoid the undue failing to utilize technology management knowledge outside the business world the broad definitions are recommended.
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The Propensity for Mandatory Audit Rotation and its Impact on Earnings Management in Europe
222-233Views:274The doubt of investors for the accuracy of financial reporting statements and the credibility of external audit functions has becoming more and more severe in the recent years due to a variety of booming accounting scandals related to earnings management occurring around the world. To cope with these serious frauds in the world of financial market, many countries have adopted Mandatory Audit Rotation (MAR) rules. Although the MAR rule has been valid around European Union (EU) members since 2016, the effectiveness of this rule has not been examined in any academic papers yet. As a result, the aim of this study is to investigate the effectiveness and the necessity of the latest MAR rule in the EU by testing the influence of audit rotation activities and audit tenure on earnings management of companies in the STOXX Europe 600 Index. Practical implications of this study will not also prove whether companies in STOXX Europe 600 Index should be required to shorten their audit tenure by rotating their audit engagement more often in order to decline the degree of earnings management, but they will also help to strengthen support for the essentiality of MAR legislations in the EU if the result indicates that longer audit tenure actually leads to more earnings management of STOXX Europe 600 Index companies.
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Role of Biomass in Urban Energy Management
62-76Views:148When making decisions on the use of energy, both on building and on city level, biomass plays certainly a role in looking for sustainable solutions. This study starts with highlighting some key points regarding urban energy management, including world urbanization trends, heat island effect of big cities and energy hierarchy in energy management. With these in mind, it is worth considering, how the shading effect of surrounding biomass can mitigate the heating needs as a wind barrier in the winter or decrease the cooling load as shadowing element in the summer, both for buildings and whole cities. These can be further enhanced by biomass integrated in the buildings’ envelope: green roofs and green walls can have significant energy conservation effects, according the characteristics of their different types. Lastly, urban disposal of biomass can lead to renewable energy generation, both in case of biogas production and waste incineration. These shading, covering and fuel possibilities all underline the importance of biomass in urban energy management.
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Vehicle Dynamic Simulation Possibilities Using AVL Cruise M
309-323Views:220In most cases, when creating vehicle dynamics simulations, we need software that can speed up model creation and simulation. There are many programs on the market for this purpose, but they have different knowledge and user interfaces. We present in this article briefly introduces the use of one of the market's leading vehicle simulation software, the AVL Cruise M.
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Increasing the Life of Mulching Tools
414-421Views:133Areas after mining or calamity are not amenable to immediate afforestation and require some adjustment. After removal of wood biomass, the rest of the residue is scattered throughout the area. To modify them, Several methods can be used to remove it. The optimal conditions for the planting environment and the subsequent adaptation process of the planting can be achieved by its mechanical, biological, chemical treatment. The basic prerequisite for a successful renewal of forests is their release from undesirable increases, in some cases from foams (trees) from mining waste. The area is also released when forest nurseries, seed plantations, etc. are established. The main purpose of the release of surfaces is to achieve the maximum throughput of the area for the machines to be moved. They wear during work. Wearing is a permanently undesirable change in the surface due to the interaction of functional surfaces or functional surface and wear medium. A tool that does not have any editing can go into a state where it can no longer be used anymore. An experiment was carried out in which 9 new teeth were placed on the rotor of the crusher and their wear patterns were observed. The article shows the progress of tool wear over time.
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Floorball position and passive sports consumption in the light of a study
142-157Views:235Research and studies done on floorbal is usually associated with medical studies, however the research and analisys of other fields peakd little interest.Thus, the aim of the study was to present the situation of floorball in Hungary and to examine the opinion of passive sports consumers about the sport. Within this we deal with the competition system of our country and the organizational structure of the federation. In our primary research, from a viewer perspective, we were interviewed as passive consumers in a questionnaire survey about their relationship to floorball. In the questionnaire we discussed whether they had ever met this sport and whether they had seen it or what attracted them to the match. We also tested their willingness to pay. The results were compared with the opinion of one of the domestic leaders of the sport, which in many cases agreed with the results. The questionnaire was completed by 153 people, more than 95% of whom had heard of the sport and most had the opportunity to become familiar with floorball at primary school. 65% of those surveyed have already seen a live floorball match that they have mostly played with friends / acquaintances. This young sport can become more and more popular among young people, not only as a complementary sport.
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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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Use Design or Technology: The Antique Römer Glass
33-37Views:132In this paper, the Römer-glass are assessed as indicator of the technology and design by using a comparative method. We identifed their designing technology methods and associated them with manufacturing centres. All of them made from green forest glass and produced in northwestern and central Europe from around 1000-1700 AD. The Römer glass present dining traditions and habits in the middle ages, furthermore like a personal belongings can be associated with the presentation of social status or individual expression.
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Entrepreneur Willingness in Case of Students of University of Debrecen
181-194Views:215This article is about the entrepeneur willingness in case of the students of University of Debrecen. There was 500 participants in the paper and online based survey who could tell their opinion about entrepreneurship in Hungary, what difficulties are they seeing and which part of the economy is where they see opportunity to start their own business. The aim of this article is to get to know how many of them and with what rate would like to start their own business, while it is examined they are from which faculty of the University, what is their family background and these facts how effects on the individual if his or her family owns some kind of business.
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Relationship between the Lean and Agricultural Companies
370-381Views:192Eliminating losses is a daily challenge for both: companies and individuals in society. Whether through the production or office work, we are wasting the most important human needs: time and energy with useless things and processes. Both are an integral part of our daily lives and are particularly important for agricultural companies. In our study, we look at the relationship between Lean and agricultural companies. We outline the risks associated with these seven Lean Losses at these companies, and how these problems can be corrected and eliminated using current methods. Our research sheds light on how technological innovations affect and influence the position of companies in the market and in financial and human resources. We examine the benefits and drawbacks of the innovations applied and the Lean processes used, and how they affect the environment around them.
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Analysis of Differences Between Levelling Networks in the County of Hajdú-Bihar
84-92Views:62The height determination of control and detail points is essential during the process of planning and manufacturing in the practice of civil engineering. Planning maps are drawn for the former, while the intended plan is set out on the ground during manufacturing, and after the manufacturing the completed installation is mapped. Using the same reference system in all three steps, both horizontally and vertically, is recommended even though in some cases it is unavoidable to change from one reference level to another. Regardless of the fact that both refer to the mean sea level of the Baltic Sea, this can create difficulties, since the difference between the EOMA and Bendefy networks used in Hungary shows varying values depending on the geographical location. The aim of the analysis is to determine a constant difference regarding the analysed settlements based on the common points of the networks.
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Investigation of the Eigenfrequency of the Bending Vibration of the Beam Clamped at Both Ends Around the Principle Directions of Inertia Based on a Single-Degree Freedom Model and a Finite Element Method Analysis
69-79Views:215In this study, we have dealt with the calculation methods of the eigenfrequencies associated with the bending vibrations of rectangular-shaped beams clamped at both ends. Said eigenfrequencies were determined analytically in the single-degree of freedom model of the beam and the case of the three-dimensional solid and three-dimensional rod models by finite element modal vibration analysis. We presented the calculation method of the characteristics of the analytical model and then calculated the eigenfrequency for a concrete example. We have described the concept of modal characteristics, and in the following, we have determined its natural frequency based on the solid-beam and rod models of the former beam. We calculated and compared the solutions belonging to the models recorded in different ways in 11 additional cases of the presented methods.
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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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A study of pressure-sinkage relationship used in a tyre-terrain interaction
186-199Views:170The vehicle applies a normal load to the terrain, which causes sinkage and motion resistance. To forecast the normal pressure distribution on the interface of a vehicle–terrain and the tractive performance of a vehicle, the response of the terrain to normal load (which is characterized by pressure–sinkage relationship equations) must be measured. This paper presents the common conventional pressure sinkage models used in terramechanic and the modification that happened to this models. In addition the features of the new models.
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Measuring the Dynamic Characteristics of Electric Motors
359-364Views:133In our previous publications [1, 2], we described our vehicle dynamics simulation program which was developed in MATLAB environment. We also discussed its use for optimizing the technical parameters of electric driven vehicles. We detailed the model and simulation of the series wound DC motor which is part of the program. Besides, we described the experimental procedure by which we can determine the electromagnetic characteristics of the motor from the input parameters of the simulation program. In the present publication we deal with the determination of the dynamic characteristics of the motor (the moment of inertia of the rotor, bearing and brush resistance torques) experimentally. Knowing the above mentioned electromagnetic and dynamic characteristics, we can carry out the simulation of the motor and the results of the simulation can be compared to the results of the test measurements.
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Surface Activation of High Impact Polystyrene Substrate Using Dynamic Atmospheric Pressure Plasma
80-87Views:159Over the last decade, the number of researches has increased in the field of bonding technologies. Researchers attempt to improve surface adhesion properties by surface treatments. Adhesive bonding is one of these bonding techniques, where it is important to see what surfaces will be bonded. One such surface property is wetting, which can be improved by several types of surface treatment. In recent years, atmospheric pressure plasmas have appeared, with which research is ongoing on surface treatments. In our research, we will deal with the effects of plasma surface treatment at atmospheric pressure and its measurement. In addition, we summarize the theoretical background of adhesion, surface tension and surface treatment with atmospheric pressure plasma. Our goal is to improve adhesion properties and thus the adhesion quality.
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Knowledge of Control Methods and their Application in the Practice of Small and Medium Enterprises in the Northern Great Plain Region
441-452Views:401Like large companies, the small, and medium-sized businesses need also all the information to ensure the efficiency and effectiveness of their business by making sound management decisions. Compared to large companies, SMEs have significant development potential, which can be created in part by the companies themselves, possibly through the introduction of new-modern management - business administration methods or economic policy measures (= targeted and efficient support system), which, by stimulating R & D & I processes, serves to increase competitiveness and contribute more and proportionally to domestic GDP and exports. The analysis presented in the study covers the controlling knowledge of the leading SMEs of the Northern Great Plain Region, the conscious or unconscious application of controlling tools, the assessment of succession, customer and supplier valuation and certain areas of managerial accounting. Overall, it can be concluded from the small sample size that the use of controlling tools is proportional to the size of the business, but nevertheless, many mid-size business executives do not require the collection and analysis of insider information that could explicitly help decision making for example through advanced costing procedures.
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Casting Issues of Thick-Walled High Pressure Die Castings
159-166Views:156Die casting is a manufacturing process for producing accurately dimensioned, sharply defined, smooth or textured surface metal parts. It is accomplished by injecting liquid metal at fast velocity and under high pressure into reusable steel dies. Compared to other casting processes, die casting is at the top end of both velocity and pressure. The high velocity translates into a very turbulent flow condition. The process is often described as the shortest distance between raw material and the finished product.
Pre-fill is a process technique that is the result of significantly delaying the start of fast shot beyond the “metal at the gate” position. It can be stated as a percentage of cavity fill or as a distance beyond metal at the gate.
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Designing of Lab-scale Anaerobic Digester Equipped with Maxblend Impeller to Evaluate Effect of Mixing on Anaerobic Digestion
404-413Views:159Operational parameters can be easily controlled at lab scale experiments for an anaerobic digestion process. Our aim is to design a lab-scale digester equipped with an impeller to investigate how the geometry of impeller and different mixing modes effect the biogas yield of digester. Further, the methods of measuring the gas volume, gas composition, mixing intensity, torque, temperature are discussed in this article. The assembling of 4 liters digester is described which can be operated at various operating parameters which control the anaerobic digestion process. Mixing is very important to enhance efficiency of an anaerobic digester. To attain mixing Maxblend impeller is used in this lab-scale digester due to its better performance for mixing and power consumption. Various design consideration has been described.
