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  • Calculations of Performance Losses for Automobile Vehicles
    210-218
    Views:
    421

    Vehicle-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.

  • A study of pressure-sinkage relationship used in a tyre-terrain interaction
    186-199
    Views:
    392

    The 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.

  • Measuring the Dynamic Characteristics of Electric Motors
    359-364
    Views:
    334

    In 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.

  • Surface Activation of High Impact Polystyrene Substrate Using Dynamic Atmospheric Pressure Plasma
    80-87
    Views:
    341

    Over 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.

  • Knowledge of Control Methods and their Application in the Practice of Small and Medium Enterprises in the Northern Great Plain Region
    441-452
    Views:
    647

    Like 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.

  • Casting Issues of Thick-Walled High Pressure Die Castings
    159-166
    Views:
    306

    Die 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.

  • Designing of Lab-scale Anaerobic Digester Equipped with Maxblend Impeller to Evaluate Effect of Mixing on Anaerobic Digestion
    404-413
    Views:
    357

    Operational 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.

  • Specialties of First SMED in Pharmaceutical Manufacturing
    1-11
    Views:
    399

    Single Minute Exchange of Die (SMED) is considered as an effective lean management method increasingly used in pharmaceutical manufacturing. By reducing change-over times and costs, the successful implementation of the first SMEDs may bring a significant increase in terms of manufacturing flexibility. The purpose of this study is present the special factors that fundamentally determine SMEDs applied especially in the process of pharmaceutical manufacturing. By focusing on a well defined part of the pharmaceutical manufacturing process, lasting from Weighing and Measuring to the end of Tablet Pressing, the study also aims to highlight the benefits of SMED itself. The findings of the research are based on the practical experiences of four SMEDs implemented in various sections of production. According to the experiences and considering industrial specialties, the implementation of SMED has to harmonise with the requirements of Good Manufacturing Practices (GMP) which are representing the golden quality standards of pharmaceutical manufacturing.

  • Examination of preferences for pork meat and pork meat products among university students
    131-141
    Views:
    341

    The purpose of this study was to examine the preferences for pork meat and pork meat products. The used sample (N=324) for the analysis came from the students of the University of Debrecen Faculty of Economics and Business. The survey was conducted by the form of online questionnaire. The results from data analyzes were based on descriptive statistics, cross-table and correlation analysis, Mann-Whitney and Kruskal-Wallis tests. Based on the results we can concluded that majority of consumers in the sample would be willing to pay more for hungarian and healthier products with less than 50%. Furthermore we can say that have a significant difference between men and women according all factors which used in analysis; have a significant difference between people with secondary and higher education according to perception of manufacturer/brand; have a significant difference between income level groups according to price and healthy eating.

  • Longitudinal Dynamic Simulation Possibilities of Vehicles Using AVL Cruise M
    743-748
    Views:
    509

    For creating vehicle dynamic simulations, in most cases, an appropriate software is required to help the dynamic model design. For this purpose several kinds of software are available in the market with different properties and user interfaces. In this article a leading simulation software of the market, AVL Cruise M, is shortly presented.

  • Overview of the Appearance of Management Information Systems In Hungarian Higher Education through the Example of the University of Debrecen
    60-68
    Views:
    291

    In recent years, the ever-decreasing number of students in Hungarian higher education has created a serious competition between institutions, in which not only national but also foreign universities prove to be competitive. In order for national institutions to be able to compete adequately in this competition, managers need to be provided with well-structured, up-to-date information that can support decision-making. The management information system, which successfully adapted at the University of Debrecen, has been in operation for years and provides significant support in data reporting and ad hoc reporting, but there are still many opportunities for advancement. The study draws attention to the importance of management information systems through the example of the University of Debrecen.

  • Analysis of Differences Between Levelling Networks in the County of Hajdú-Bihar
    84-92
    Views:
    302

    The 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.

  • Survey of the Application Fields and Modeling Methods of Automotive Vehicle Dynamics Models
    196-209
    Views:
    505

    In this paper, a review is presented on automotive vehicle dynamics modeling. Applied vehicle dynamics models from various application fields are analyzed and classified in the first section. Vehicle dynamics models may be simplified because of different reasons: several control/estimation/analysis methods are suitable only for simplified models (e.g. using control-oriented models), or because of the computational cost. Detailed/truth models of vehicle dynamics represent another field of vehicle dynamics modeling, these models play an important role in the virtual prototyping of vehicles. In the second section, the main modeling considerations of vehicle dynamics are presented in longitudinal, lateral and vertical directions. Various physical effects must be considered in the case of vehicle dynamics modeling, a lot of these effects are significant only in a specific direction of the vehicle body, which is the main potential of model simplification. The section presents vehicle modeling considerations in all of the three translational directions of the vehicle body.

  • The Effect of MMS Lubrication on Surface Roughness During Machining
    452-457
    Views:
    228

    I display this paper the chipping front metal of cutting allocated geometric, considering particular the friction. I catch the attention energy's balance sheet someday metal of cutting, open one new direction the manufacture technology. I display this new direction's metal of cutting condition. but built I delineate his paper final division this new policy searching programme, consumed trial instruments as well as the evaluation's mode.

  • Synthesis of Polylactic Acid (PLA) by Polycondensation Method
    286-293
    Views:
    589

    The Polylactic acid (PLA) is compostable and natural renewable sourced plastic type. Its mechanical properties quite similar to the PET, therefore the PLA is a good alternative for strongly ruled food industrial application. The PLA only has one critical attribute – the relatively low glass transition temperature. According to the relevant literature the glass transition of PLA is in the range of 40-70°C. In light of this fact, this material can be used only in that segments of food industrial field where the packaging process temperature are under of the lower limit of Tg range. The actual Tg of a material is highly depends on the molar mass and material structure, therefore the molar mass and the structure of material should be designed according to the future requirements of application and procedures.

  • Optimization and Analysis of Structure about Lifting Device of Logistics Sorting
    425-431
    Views:
    308

    The lifting device of a logistics sorting machine needs high frequency upward and downward reciprocating motion therefore the cutting fork arms and matching parts of the shaft are often worn out. In this paper the problem of the shear fork types applied for the lifting mechanism is studied at first. Then the advanced numerical simulation software ANSYS adopted for the lifting mechanism of the shear fork type, and the means of virtual simulation is introduced. Hence the possible location of faults and fault modes are analysed. Then improving measures about the lifting mechanism of the logistics sorting machine are suggested.

  • Combustors with Low Emission Levels for Aero Gas Turbine Engines
    503-514
    Views:
    768

    The aircrafts are responsible for emitting several types of pollutants, especially the pollutants in the form of NOX, CO2, CO, UHC, SOX and Particulate Matter PM (smoke/soot). The impact of aviation emissions on the global is well known, where these emissions modify the chemical and microphysical properties of the atmosphere resulting in changes of earth’s climate system, which can ultimate in critical changes in our planet fragile ecosystem, also the pollutants produced by aircraft engines cause many health problems. This is why the International Civil Aviation Organisation (ICAO) is seriously seeking to control the emission levels by issuing new standards during the successive meetings of the Committee on Aviation Environmental Protection CAEP (CAEP/01 in 1986, CAEP/2, CAEP/4, CAEP/6, CAEP/8, etc). The new regulations include more stringent standards aimed to reduce emission levels, this led to increased interest in low emission technologies. In this paper, a comprehensive review of low emissions combustion technologies for modern aero gas turbines is represented. The current low emission technologies include the high Technologies Readiness Level (TRL) including RQL, TAPS, DAC and LDI. Also, there are advanced technologies at lower TRL including LPP, ASC and VGC.

  • Exhaust System Muffler Volume Optimization of Light Commercial passenger Car Using Transfer Matrix Method
    132-138
    Views:
    375

    Nowadays, the automotive industry is focused on weight and size reduction. Main advantage of this weight and size reduction are improving the fuel economy. The specific fuel consumption of a vehicle can be improved through e.g. downsizing area of heat loss, if we focus on vehicle with weight reduction. Weight reduction can be done by replacing material or by changing the size (dimensions) of components. In the present work we have focused on Audi A6 muffler, troubleshooting and optimizing the muffler by changing pipe length of inlet and outlet, also by replacing the original mesh plate to porous pipe. Based on optimization, prototype has been built with the help of 3D design tool CATIA V5 and the calculations of transmission loss (TL) have been performed by MATLAB. Plane wave-based models such as the transfer matrix method (TMM) can offer fast initial prototype solutions for muffler designers. The principles of TMM for predicting the transmission loss of a muffler was used. Result of this present study of an existing muffler has been analysed and then compared with vehicle level test observation data. Noise level have been optimized for new muffler design. Other literatures were played significant rule for validate our results.

  • Analysing the Possible Connection Between Dark Triad Personality Traits and Ethical Attitudes of University Students
    57-67
    Views:
    541

    In our paper we examined the possible connection between the Dark Triad personality traits and ethical attitudes among university students. The analysis of both topics has become the focus of interest in the past decades. Researchers consider the impact of many factors in the background of ethical attitudes and behavior. Among other things, personality is also a potential factor. The Dark Triad personality means the coexistence of the socially undesirable narcissism, Machiavellianism and psychopathy. Such people are characterized by self-love, aggression, the lack of guilt or conscience, so they are less likely to have ethical attitudes. In our research, this connection was examined by a questionnaire survey conducted among first year students of University of Debrecen Faculty of Natural Sciences and Technology and Faculty of Economics and Business. Respondents completed the validated Dirty Dozen questionnaire which was developed to measure Dark Triad personality and a questionnaire adapted from Lozier's research in which respondents were asked to evaluate school situations whether they are ethical or unethical and to what extent they are unethical. In our research, we were looking for significant relationships between the strength of the Dark Triad characteristics and the ethical judgment of situations. We also analyzed the differences between men and women and students of the two faculties.

  • Safety Index Based on Geometric Probability Is Proposed to Represent the Uncertainty of Soil Parameters for Spread Foundations
    43-52
    Views:
    345

    The overall factor of safety in geotechnics can be defined as the product of four partial factors of safety. One of these partial factors represents the uncertainty of the soil parameters. Based on geometric probability, a safety index is proposed to calculate the uncertainty of the soil parameters for spread foundations. Numerical examples have also been presented.

  • Simulation of Hot Rolling by Cellular Automata
    190-195
    Views:
    375

    Our research is focusing to one of the most complex and important production step of flat rolled products that is the simulation of hot rolling. During hot rolling two phenomena as work hardening and the process of regeneration of crystals has strong influence for physical properties of microstructure of aluminium alloys. It needs to be taken into account in case of rolling technology steps and development. When we talk about aluminium the dynamic softening in fact it is dynamic recovery that is followed by dynamic recrystallization. It goes in the same order of magnitude rate. But in steels the recovery has only a minor effect. Hot rolled and newly modified grain structure is influenced by these dynamic phenomena. Hot rolled grain structure goes through significant changes under further production steps like cold rolling and heat treatments. But aside from these intermediate production steps the microstructure that we get after hot rolling has significant effect for mechanical and grains structure of the final flat rolled product. Proper technology planning is essential that for cellular automata simulation method can ensure useable and good solution for the simulation of recrystallization.

  • Investigation of Aluminum Dross as a Potential Asphalt Filler
    445-451
    Views:
    328

    There is a great concern about utilizing different waste materials all over the world. Stockpiling in landfills is not a final solution, therefore researchers try to find alternative methods to utilize these materials [1-5]. One potential area may be road construction. Fillers are one of the most important components of asphalt pavements. It has a dual role. First of all, these fine grained mineral materials (d<0.063 mm) enhance the cohesion with bitumen. Second is to fill the gaps between the particles to produce more compact mixture [6]. The aim of this research is to reveal the possibility of utilization of aluminum dross as a potential asphalt filler. This material, which is a by-product of aluminum casting process, is produced in large quantities year by year and its storage in landfills is not a proper solution. Therefore, there is an increasing demand to utilize this material. During the research material structural tests were made, which can characterize the samples (limestone powder, dross), and the cohesion between bitumen and filler can also reveal. Particle size distribution, BET specific surface area and porosity were investigated. Scanning electron micrographs were taken and oil adsorption test were also made.

  • The Efficiency of Intellectual Capital as a Crucial Factor of Innovation
    419-428
    Views:
    436

    In today's global economy, there is a substantial shift from manufacturing to services, which challenges both economic policymakers, business stakeholders, owners, suppliers, competitors, and ordinary people: restructuring will encourage all economic players to learn how to adapt to new trends. That is why our research focuses on innovation and the ability of companies to create value. The IT sector is currently one of the fastest-growing and most innovative sectors within the service industry. The success of IT companies is greatly determined by their ability, how to make effective use of their intangible assets at their disposal, including intellectual capital, which is defined as a non-financial asset. So the question may arise: how is it possible to quantify and in monetary terms the intellectual capital of the companies to be examined? That is why, we calculated for the most successful Hungarian IT companies the widely recognized index, the VAICTM index, for which domestic calculations are not yet available. Indeed, this indicator eliminates the lack of information stemming from reporting standards by the methodology relying on publicly available financial reporting data. The indicator itself is a top indicator whose two main sub-indicators quantify the effectiveness of intellectual capital and physical capital.

  • Review on Construction Procedures of Driving Cycles
    266-285
    Views:
    487

    The goal of this paper is to give an overview of the literature of construction techniques of driving cycles. Our motivation for the overview is the future goal of constructing our own driving cycles for various types of vehicles and routes. This activity is part of a larger project focusing on determination of fuel and energy consumption by dynamic simulation of vehicles. Accordingly, the papers dealing with sample route determination, data collection and processing, driving cycle construction procedures, statistical evaluation of data are in our focus.

  • The Effect of annealing temperature on corrosion resistance and microstructure of Zr-Sn-Nb-Fe alloy
    420-424
    Views:
    280

    The Ti-2Al-2.5Zr titanium alloy plate in beta phase water quench at different times of the reentry after annealing is implemented while primary phase number and size distribution of samples are obtained. This research is carried out on corrosion behavior in 3.5% [mass fraction] NaCl solution. Experimental study showed that after the beta phase water quenching Ti-2Al-2.5Zr titanium alloyed after 500 oC annealing when partial recrystallization happened. There seems to be lots of tiny dispersion in the alloy that was annealed with its samples of six-party [HCP] structure of Ti, Zr, Al phase 2 with the dimension below 100 nm. Reaching 500 oC when the rate of annealing at a primary phase of the sample at 550 oC is low 90% of the primary phase is less than 100 nm. The changing of the rule of present decreasing also triggers little difference overall. Precipitation in the process of annealing Zr [Nb,Fe,Cr] 2is less that proves to be good for corrosion resistance.