a borítólapra  Súgó epa Copyright 
Analecta technica SzegedinensiaVol. 9. No. 1. (2015.)


  • S. Bodzás :

    The objective of this publication is creation of computer geometric models (CAD) of developed in Diósgyőri Machine Factory and using exact production geometry first produced (grinded) cylindrical worm gear drive having arched profile by Illés Dudás [3, 4, 5] for connection analysis, Finite Element Method analysis, etc. Since the worm and worm gear wrap each other, that is why the worm gear has to be produced by a tool geometry of which is similar to the worm geometry. Knowing of the Connection I. Statement tooth surface of driven element which is wrapped by driver element is defined by numerical calculations. The CAD model of the worm gear could be designed by adaptation of interpolating B – spline surface to the tooth surface points of worm gear.

    Keywords: worm, worm gear, hob, CAD, modelling

  • B. Zsótér ,
    R. Balog :

    In this article we studied one aspect of consumer’s habit, namely the consumption of mineral water in the middle of Hungary. We applied so-called multiple methodology during the field work. We carried out a questionnaire survey as main method of research in CBA-supermarkets of three different settlements. The major part of the consumers considered the price as the most important factor of purchase. They beleived the secret of the success of ’Mizse’ in it. The interest in the pack of 0.5 litre was surprisingly great. The product of this size of packing has been released later. Almost 58% of the costumers buying ’Mizes-water’ would certainly try the fizzy drink called ’Mizse-lemon soda’, too. The initial results echoe the need of further investigation.

    Keywords: mineral water, packaging, consumption behaviour, price, brand, factors influencing purchase

  • S. Raţiu ,
    V. Alexa ,
    I. Kiss :

    This paper presents an educational application, with practical realization, regarding the functionality simulation of a gasoline injection system using a computer and a peripheral afferent, along with its control circuit. The application replaces the ECU (Engine Control Unit) and controls a demo injection rail, equipped with four gasoline injectors with different shapes of flow. The equipment provides the flow shape visualisation and injection parameters change according to the engine load conditions, which can be simulated by the electronic equipment through the virtual interface. The system allows the determination of the gasoline amount injected by the various types of fuel injectors, in a certain period of time and at different pressures of the fuel, depending on the load and the speed of the engine.

    Keywords: gasoline injection, simulation, injection parameters

  • A. Czibolya ,
    E. Lendvai :
    Examination of foie gras consumption habits18-24en [359.15 kB - PDF]EPA-02592-00003-0040

    The goose liver is a special product produced by the force-fattened geese. The manufacturing process has thousands of years of history, which has grown to be a key sector for Hungary. First, we intended to get to know the producers side on force-feeding of geese in the past and present during our research – this serves as a basis of structured interviews with 10 workers in the administrating sector. On the other side, we investigated the consumers’ habits and opinions in relation with goose liver with a questionnaire. The first set of questions was directed specifically to consumer habits, including how often the product is consumed and why it is so. The second set of questions was intended to assess the knowledge on the process and other topic-related issues. Finally, we could establish that this type of products called ‘hungaricum’ is very important for Hungary because of the export and it also provides the basis for many farmers.

    Keywords: structured interview, questionnaire survey, consumers’ preferences, animal welfare

  • A. Papp ,
    J. Krisch :

    National and international surveys show that people still do not have appropriate knowledge of and attitude to food safety. Therefore more and more countries organize educational courses to improve skills and knowledge regarding food safety. In Hungary the National Curriculum 2012 contains the program for food safety education.

    The aim of our survey was investigation about knowledge and attitude of primary and secondary school students towards food safety. The questions, according to international surveys, fell into 5 categories: personal hygiene, keeping food at safe temperatures, adequate cooking, avoidance of cross-contamination, and safe source of foods. Statistical evaluation was done using SPSS 20 software. Significant differences were evaluated by logistic regression, Chi square test, and crossing table analysis.

    Results showed that there was no significant difference among primary school students regarding gender or residence (village or town) in knowledge of food safety. Their attitudes showed more significant divergence. Logistic regression investigation has showed that there was a good correlation between knowledge and attitude of personal and kitchen hygiene. In conclusion, our students have presented more or less the same results as the others from international questionnaires. Even though, we need to improve knowledge and skill in food safety.

    Keywords: attitude, food safety, knowledge, logistic regression, primary school, secondary school

  • N. M. Hromią ,
    V. L. Lazić ,
    D. Z. ©uput ,
    S. Z. Popović ,
    V. M. Tomović :

    Collagen casings are commercially used in sausage production. In this paper, collagen film that is used for sausage casings was laminated with chitosan film to produce barrier casing film.

    Chitosan coating was prepared by dissolving chitosan powder in 1% acetic acid. After dissolving chitosan, caraway essential oil, wetting agent Tween 20 and different amounts of beeswax, from 0 to 25 g were added to the solution. The solution was coated on collagen film surface in three layers, using a sponge brush to make laminated films. Films were air dried at temperature t =23 °C ± 2 °C. Uncoated collagen film was used as reference.

    Film thickness, water vapor barrier properties and FTIR spectra were determined. With growing amount of beeswax added to the chitosan layer, film thickness grew from 112 μm for laminated film with 5 g of beeswax to 225 μm for film with 25 g of beeswax, compared to 83 μm for collagen film. Water vapor barrier properties improved with growing amount of beeswax in chitosan layer, ranging from 130.71 g/m224h for laminated film with added 5 g of beeswax to 66.96 g/m224h for the film with 25 g of beeswax, compared to 290.64 g/m224h for collagen film. Addition of beeswax showed great potential in lowering water vapor permeability of laminated collagen-chitosan film. FTIR spectra could be used to determine quantitative law dependency between added amount of beeswax and spectra absorption values,as well as to prove compactness of chitosan-beeswax layer.

    Keywords: edible biofilms, chitosan, collagen casings, beeswax, characteristics

  • A. J. Czmerk :
    Increasing of stiffness of double-acting pneumatic cylinder39-45en [754.45 kB - PDF]EPA-02592-00003-0070

    Position keeping properties of actuators depend highly on their stiffness. The low stiffness of pneumatic systems is well known, which is disadvantageous during positioning and when a position has to be kept. It is one of the reasons why hydraulic systems have advantages over pneumatic systems when it comes to positioning tasks. This paper deals with the analysis of the passive stiffness of a double-acting cylinder. The stiffness of pneumatic cylinders is derived as a function of chamber pressures determined by the bulk modulus of pneumatic systems. The stiffness of a passive system of the chambers is written by the pressure change through small displacement of the piston and as a result of the restoring force. In case of the passive system the effect of the valve actuation is neglected. From the deduction it is clear that the stiffness of a cylinder changes along the stroke, dead volumes at the end positions play a relatively important role. The results are compared with the restoring forces of the piston seals and other sealing elements in the stiction region. The restoring effects of the elastic elements were determined by measurements.

    Keywords: pneumatic system, stiffness, friction, stiction

  • I. Kiss ,
    V. Alexa ,
    S. Raţiu :

    The developments of new and innovative materials are contributing significantly to the large scale such as automotive industry. Century by century uncountable inventions and developments were dedicated to synchronized technological advancement. Smart materials are highly efficient materials and their performance comes at high costs associated with the high level of R&D involved. Therefore, invention of these materials conceptualized to produce effective sensors and actuators according to the purpose. Some everyday items are already incorporating such smart materials, and the number of applications for them is growing steadily. Invention of functional and intelligent materials introduced new concept of intelligent infrastructure systems, autonomous systems, smart structures and robotics in the bygone years. Smart materials include the piezoelectric materials (PZT).

    Keywords: automotive industry; innovative technologies; sensors; smart materials; Lead Zirconate Titanates (PZT)

  • J. Szendrei ,
    E. Szűcs ,
    G. Grasselli :

    The most sustainable energy is the energy not used. Best way to (not) use energy is the proper design of a facility or an energy consuming system. The remaining energy needs have to be covered with energy utilisation of waste materials, renewable energy sources and, until the previous solutions are not sufficient to satisfy the energy demands, the last is the use of conventional fossil and nuclear energy sources. In terms of renewable energy, biomass has an important role today. However, there is a difference between available inputs and utilisation when considering biomass energy possibilities in rural and urban context. This paper suggests biomass energy possibilities that are recommendable in rural context: possibilities of solid biomass combustion, of liquid biofuels and of anaerobe digestion. Also important are possibilities of solid biomass combustion and wet biomass digestion for urban energy production, although with some remarks on system considerations of urban biomass. Most advanced solutions for sustainable management of biomass energy include circular systems, both in rural and urban context, as recommended.

    Keywords: biomass, energy, sustainable, urban, rural, circular economy

  • S. Nagy :

    Non-interacting magnetization Taylor expansions are calculated in 2D and 3D at high external field according to the vibrational model. In this approach all dipoles are moved as a linear pendulum independent from each other. The temperature is taken into account according to the equipartition theorem, thus all particles have the same kinetic energy: kBT/2 in 2D and kBT in 3D. The expansions valid only at high external magnetic field due to the linearisation of initial differential equation. On the second part of this paper the Maxwell-Boltzmann distribution is taken into account to determine the probability density function of the angular velocity. The ratio of the particles which has zero angular velocity in 2D is the maximum, in 3D is zero. Therefore the theoretical prediction is in better agreement with the exact formula of magnetization in 2D than in 3D. In this approach the effect of negative magnetization is able to come into existence in the non-interacting fluidum.

    Keywords: Langevin function, vibrational model, non-interacting magnetization, linear pendulum, 2D and 3D magnetization, negative magnetization