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  • Comparison of oxidation procedures for removing neonicotinoid insecticides from model solutions
    91-98
    Views:
    87

    The main objective of this study is to remove three neonicotinoid insecticide agents (thiametoxam, acetamiprid, thiakloprid) from model solutions using ferrate and persulfate-based oxidation techniques. In our experiments, an analytical method was developed for HPLC-MS/MS coupled techniques and tests were performed to determine how the molar ratio of the starting target compound/oxidant affects the degree of removal of the target components.

  • An Analytical Solution for Static Problems of Cantilever Curved Beams with Variable Cross Sections
    226-233
    Views:
    136

    This paper gives an analytical method to obtain the deformation of a cantilever curved beam. The curved beam considered has circular centre line and the thickness of the cross section in radial direction depends on the circumferential coordinate. The kinematics of the Euler-Bernoulli beam model is used to formulate of governing equations. The curved homogeneous and isotropic elastic beam is fixed at the one of the end cross section and on the other end cross section is subjected to concentrated forces and a couple. A numerical example illustrates the applications of the derived formulae.

  • Vehicle Dynamic Simulation Possibilities Using AVL Cruise M
    309-323
    Views:
    194

    In 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.

  • Examination of Leadership Style with MLQ Among Small Enterprices in Szabolcs-Szatmár Bereg County
    36-47
    Views:
    781

    The Full Range of Leadership Model describes different behaviors and styles that differentiate leaders. Managers and leaders use each style, but not egally. The Multifactor Leadership Questionnaire (MLQ) measures the full spectrum of leadership styles. It is widely used by researchers and practitioners. In my paper, after a short theoretical review of the topic and the description of the styles, my empirical analysis is also presented. In my work I examined the leadership style of chief executives of small enterprises in Szabolcs-Szatmár-Bereg county, with MLQ.

  • Measuring the Dynamic Characteristics of Electric Motors
    359-364
    Views:
    105

    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.

  • Role of Lean and Agile Supply Chain Models for Pellet Fuel Technologies
    119-130
    Views:
    148

    Business organisations constantly strive to improve their processes, both internal and external. Within the supply chain of a product, different strategies can be applied. This paper aims to answer the basic questions like what is the core of lean and agile SCM strategies, what are the differences of the two models, and how can they be combined. This paper examines further, which of these SCM models and what elements of them can be applied for wood pellet supply chains, also examining the possibility of their combination. The result of these examinations is, that even though fuel pellets can be considered as simple commodity and not a very innovative product, diversity in input characteristics, optimization of fuel pellet technology process variables and changes in output market qualities and quantities need sometimes agile, flexible answer from pellet fuel SCM. The basically lean character of pellet fuel technologies and SCM can further enhanced by implementing agile SCM model elements, as is the increased integration of suppliers into the supply chain.

  • How Does Public Debt Change when the Next Crisis Comes - and It Will Come!/the Expected Evolution of Greece's State Debt in the Next Crisis Period/
    91-104
    Views:
    227

    It has recently been announced that Greece may withdraw from the Euro-Zone permanent rescue fund's aid program because it has successfully met the conditions imposed on it. Creditors and credit qualifiers also agreed that the Greek economy was on a good growth path. That is why there is a chance that by 2030 the current sovereign gross debt of 182.7 per cent of GDP will fall to 123.3 per cent. The author finds this statement unfoundedly optimistic. He argues that the Greek debt ratio – despite the current optimum economic fundamentals – does not seem to be sustainable. He sees greater probability that in the near future it will again be necessary to release some of the Greek debt. Debt reduction will also mean a new orderly state bankruptcy. The study seeks to highlight how vulnerable and risked the sustainability of current Greek debt financing. Using a macroeconomic model, it shows and justifies how the Greek sovereign debt changes in the case of a crisis that is only half the extent of the previous subprime crisis. If this happens, by 2023, the state debt will rise to more than double the national product, and by 2030 only to the present, otherwise critical, level. It follows that the high risk of financing Greek state debt remains unchanged.

  • Longitudinal Dynamic Simulation Possibilities of Vehicles Using AVL Cruise M
    743-748
    Views:
    231

    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.

  • New Method for Dynamic Tribological Test of Engineering Polymers
    25-29
    Views:
    116

    In this article, tribological tests of Polyamide 6 (PA 6), Ultra High Molecular Weight Polyethylene (UHMW PE) and Polyoxymethylene copolymer (POM C) by a new testing method is introduced. The tribometer used in the test is capable for pin-on-disc measuring within all possible layout known in tribology practice, otherwise can be modified into special model of fatigue sliding test. The pin was a specimen made from examined materials, always in contact with a rotating metal disc under a normal load, which is usually static. However, since vibration exists in every practical scene as an important phenomenon, for instance in turning process, we added vibration load into the test. The supplement load is generated by a special-designed vibrating machine. Then properties of examined materials can be studied more profoundly under vibration load. As a result, different value of friction coefficient in static and vibration load have been discovered and taken into comparison.

  • Survey of the Application Fields and Modeling Methods of Automotive Vehicle Dynamics Models
    196-209
    Views:
    201

    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.

  • Business Students’ Attitude to Social Responsibility
    1-10
    Views:
    260

    The companies’ most important goal is the satisfaction of consumers’ needs and the profitmaking. But nowadays the companies have to deal with the activity of corporate social responsibility, too. Therefore it can be interesting to research about the next questions: can ethics be taught? Do we have to teach ethics in the schools and especially in the business schools? What are the students’ attitudes toward the social responsibility? Are students sensitive and open-minded connection with this issues? The aims of the study were to examine responsible management attitudes among business students at the University of Debrecen (Faculty of Economics and Business). We draw their CSR pyramid (based on Carroll model) and present their opinion in reference to business education’s role in social issues.

  • The Impact of Optical Character Recognition Artificial Intelligence on the Labour Market
    9-16
    Views:
    349

    Because 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.

  • An Economical Mathematics Model
    39-44
    Views:
    83

    In the frame of the project NTP-NFTÖ-17-C-159, one of my main tasks is to present the possible applications of teaching mathematics in high schools and in higher education. Beside this, I would like to illustrate that, in many cases, how useful and, in certain cases, indispensable the use of mathemathical softwares is during the solution of a complex problem.

  • Survey of the Dynamic Modeling Methods of Light Vehicles
    723-727
    Views:
    208

    Vehicle dynamics models can be classified into two groups based on the model simplification. There are simplified models based on neglections, these models do not contain all body directions: longitudinal, lateral and vertical directions. There are several reasons for the simplification: control, estimation and analysis methods can be used only with simplified models, or another reason is the computational cost. Apart from simplified models, there are detailed/truth vehicle dynamics models which aim is to provide a virtual plant of the real vehicle for virtual prototype-based development. In this paper, some simplified vehicle models are presented, after a short introduction.

  • Analysis of Social Media Activities - Through the Examination of Handball Clubs Competing at Different Levels
    39-53
    Views:
    241

    In Hungary, handball enjoys special attention and support, this is true not only for our country, but also for Europe, and the sport is gaining more and more space worldwide. One of the biggest innovations of the last two decades is certainly social media, which has reformed the basic strategies related to information transfer and traditional marketing activities. The processes of content production on these platforms have radically changed, which every sports club should pay attention to, as they can gain significant advantages in terms of economics, marketing and community building if they are able to communicate well. Three sports clubs competing at different levels were compared during a qualitative study in terms of their social media marketing strategy activities, namely PICK Szeged, Balatonfüredi KSE – BFKA Balatonfüred and DEAC handball team. The basic concept of this research model was built on how the online marketing communication activities of club teams fighting for different professional goals at different levels differ from each other, as well as what are the development opportunities and aspects that can be used as effectively as possible on social media platforms. The handball club teams agreed on several research questions, but a significant difference could also be discovered in one area, in which the professionals responsible for social media disagreed or represented a different point of view. Looking at my results, it can be concluded that behind a successful online marketing strategy there is always serious preparation and planning work, as well as the diversification of content production on different platforms, because the consumer communities of the platforms are also different from each other.

  • Examining the Movement Differences in the Behavior of Normal and Rack Railway Vehicle
    96-103
    Views:
    259

    The rack railway is a special type of railroad. There weren”t much built worldwide, and their number is decreasing. Now, in Budapest, there is a possibility to create an interoperable vehicle, based upon the experience gained from the previously operated line, and all the research regarding its unique characteristics. One from the many important sector of its operation, is the rail/rack/vehicle system. Its mechanical model is far more complex than a traditional railroad vehicle. We will demonstrate its behaviorial differences from a traditional railroad vehicle.

  • Parameter Estimation of Drag Coefficient and Rolling Resistance of Vehicles Based on GPS Speed Data
    109-115
    Views:
    145

    In this paper, a parameter estimation method of the model-based design approach is applied to estimate the drag coefficient and the rolling resistance coefficient of a vehicle. In fact, a constant-force parameter (c_const) and a velocity-square-force parameter (c_square) are in the vehicle model, and these result in the sum force applied along the translational DOF that models the vehicle. It is only an assumption that the constant force is the rolling resistance and the force proportional to the square of the velocity is the drag force of the air. Only GPS speed data is used for the estimation process. The conclusion is that parameter estimation is a good alternative when expensive measurement devices are not available to measure the force losses separately and directly.

  • Micromechanical Model of Dry Friction Hybrid Polymer Composite Clutch Facings
    335-340
    Views:
    88

    Modelling the complex coupled thermomechanical and tribological contact of a dry friction clutch system between cast iron flywheel and scatter-wound hybrid composite clutch facing requires a thought through investigation of the friction material properties and behaviour. Challenges of the creation of a mechanical stiffness matrix for such a complex material are described in this paper along with simplification ideas and solutions.

  • Visual Analysis and Geometric Modeling of Metal Foams
    89-92
    Views:
    101

    The development of an efficient procedure for 3D modelling and finite element simulation of metal foams
    is one of the greatest challenges to engineer researchers nowadays. Creating 3D CAD model is alone a demanding
    engineering task due to its extremely complex geometry, and the proper finite element analysis process is still in the
    center of the research. The aim of this project is to analyze the related literature and to adapt the results may be
    considered.

  • Analysis of Activity Times in the Process of a Wooden Box Manufacturing
    475-484
    Views:
    119

    The main target of companies is to earn money and achieve profit. In order to fulfil these needs, companies have to reduce their costs. Cost reduction is often associated with bad quality products, but it could be done in a different way. Sometimes it is enough to examine only their own processes and then benefit from the process optimization, process improvement or process scheduling. In this article a case study is presented, in which the differences in a production scheduling are evaluated with the application of Monte-Carlo simulation and descriptive statistics. At the end of the paper the most efficient material sequence is selected at the manufacturing company by using weighted sum model

  • Digital Twin and Shadow in Smart Pork Fetteners
    515-520
    Views:
    274

    This paper introduces our ongoing research in the field of smart livestock farming. The base idea in this research is to take some industry based concepts, and adapt them into agriculture. In Industry we live the  fourth industrial revolution, which is not a technical, but an organization revolution. So in this concept there are two key ideas, which are digital twin, and digital shadow. This article is about creating digital twin and digital shadow of a modern pig fattener. These models are based on the literature, and are identified on the data shared in these. However, these models can’t be used on real systems before identifying them on the actual circumstances. At this stage of research only digital twin of the product was created, and only some aspects of it. This however can simulate an average porkers feed consumption, weight growth and calculate the weight on certain stages of breeding. Further development is ongoing and our target is to make a fully functional model of a pig fattener.

  • Kinematics and Control of a Planar Cable Robot
    88-95
    Views:
    131

    This paper deals with the kinematics and control of a planar cable robot [1], which is driven by four DC motors with gear. Cable robots are frequently used e.g., for the motion of cameras in sport halls and stadiums and also in high storage logistical systems [2]. Main goal of this research work is to design and build a test bench with low budget, which can model the motion of real life cable robots.

  • Floodresc – Disaster Management in case of Flooding in the Hernad Watershed
    181-187
    Views:
    96

    The aim of the Floodresc project is to develop a GIS based decision support system that can help the defense and rescue operations of the Disaster Management Directorate during any floods in the Hernád River. In the project, a geospatial database covering the entire river basin, a modeling application for predicting the extent of flooded areas in time, and a logistics model supporting defense-related transportation tasks will be developed.

  • Fémhabstruktúrák elemzése és geometriai modellezése
    145-152
    Views:
    121

    The development of an efficient procedure for 3D modelling and finite element simulation of metal foams is one of the greatest challenges to engineer researchers nowadays. Creating 3D CAD model is alone a demanding engineering task due to its extremely complex geometry, and the proper finite element analysis process is still in the center of the research. The aim of this project is to analyze the related literature and to adapt the results may be considered

  • Comparative Analysis of Collaborative Robots
    1-16
    Views:
    167

    In our study, we provided a comparison of four robot arms used in industry to determine  the most suitable model to adopt in university education. We investigated robot arms from the following manufacturers: ABB, Kuka, Universal Robots, and Techman Robot. The multi-criteria system was grounded on the important factor and experience. Following this, each aspect was ranked using the Analytical Hierarchy Process (AHP) method. In addition, the order among the four alternatives was established by using the Kesselring method. The present study describes a selection method for industrial robots in the academic area.

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