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Analecta technica SzegedinensiaVol. 13. No. 1. (2019.)

Tartalom

  • Sándor Bodzás :

    Knowing of the geometric designing process of a straight bevel gear we have worked out a computer aided software with which this designing process could be eased. We have designed some bevel gear pairs having concrete geometry in the function of the modification of the number of teeth of the pinion and created the CAD (Computer Aided Designing) models of these gear pairs. After that the TCA (Tooth Contact Analysis) analysis could be followed. The load force have been situated on the top of the tooth edge on the tip circle. The established normal stress, normal elastic strain and normal deformation could be analyzed. Based on the results we can create the necessary diagrams and define the conclusions.

  • Zsuzsanna Bacsi ,
    Zsolt Hollósy :
    A yield stability index and its application for crop production11-20en [583.13 kB - PDF]EPA-02592-00012-0020

    A good crop production technology should provide high yields under varying environmental conditions, i.e. keep yield fluctuations small. The magnitude of fluctuations is usually measured by statistical indicators of average dispersion, e.g. the standard deviation. However, while many small fluctuations are usually well tolerated by the farmer, an extreme yield may be a serious risk factor. The present research introduces a yield stability index developed which measures the frequency of extremely high and extremely low yields. The index is tested for 10 countries and 18 crops for 2004-2016, comparing it to 1961-2000, pointing out possible agricultural policy implications.

  • Krisztián Attila Bakon ,
    Adrienn Skrop ,
    Szilárd Jaskó ,
    Tibor Holczinger :

    One of the new challenges of the 21st century is the Industry 4.0. Manufacturing companies moving away from mass production and getting closer to customized production and manufacturing of customized products through digitization. The expectations are high, meeting the requirements is a real challenge to industrial partners. In order to help meet the challenges the University of Pannonia Nagykanizsa Campus started to establish a fully automatized industrial laboratory. In this paper the architecture of the Industry 4.0 laboratory and the purpose of the Factory Subsystem is presented.

  • Ferenc Kis ,
    Nikola Maravić ,
    Szabolcs Kertesz ,
    Zita Istvan ©ereą :

    The aim of this study is to compare the environmental impact of liquid inverted sugar (77°Bx) produced with enzymatic hydrolysis of beet sugar and HFCS (75% DM) produced from corn in a wet milling process. Given the different sweetness equivalents of liquid inverted sugar (77°Bx) and HFCS (75% DM), the reference flows were defined as 900 kg of liquid inverted sugar or 1000 kg HFCS. The analysis was performed with the life cycle assessment (LCA) method focusing on the cradle-to-gate stage. The inventory data of liquid inverted sugar processing were supplied by a producer while the LCA of HFCS relies on secondary data (literature) which describes the material and energy flows associated with glucose production. Life cycle inventory of relevant inputs and outputs were available from the Ecoinvent 3.4 database. Environmental impacts were calculated with the ReCiPe 2016 (H) life cycle impact assessment (LCIA) method. LCA results have revealed that inverted liquid sugar has a lower impact in 14 out of the 18 analysed impact categories. Consumption of inverted liquid sugar (>77°Bx) instead of HFCS (75% DM) could lead to significant reduction in GHG emissions (by 38%), fossil energy (by 31%) and water (by 95%) consumption, and reduces the required land area by 67%.

  • Viktória Papp ,
    Sándor Beszédes ,
    Dóra Szalay :
    Mechanical and energy examination of different agripellets40-47en [589.34 kB - PDF]EPA-02592-00012-0050

    As an indirect consequence of climate change, the reduction of carbon dioxide emissions, the energy utilization of agricultural by-products will be increasingly emphasized in the future. Hungary has a large potential of agricultural residues of which is a big part could be used for energy purposes. Common feature of this by-products is that thay are originally difficult to handle and they have a small bulk density. Pellet production is one possible way to utilization, however the high ash content and low ash melting point cause problems in pellet burner equipments. Mixtures of different plant residues (wheat straw, rape seed stem, sunflower husk) and agripellets have different energetic and mechanical properties. Besides high ash content and low ash softening temperature, mechanical properties can also significantly affect the quality of pellets as well as the efficiency of firing. There were also significant differences in diameter, length, bulk density and mechanical durability of pellets.

  • Dániel Dorogi ,
    Betti Bolló ,
    Szilárd Szabó :

    In this study flow around an axial flow fan is investigated by the means of CFD computations using the commercial software package, ANSYS Fluent. The rotation speed of the impeller was set to the constant value of n = 2500min-1. The results obtained from the computation are validated against those from measurements; good agreements can be seen. The effects of two different external disturbances are analysed. First, the fan was place into a uniform stream where the free stream velocity is varied between U = 0 and 100 km/h. After that, a computation is carried out for U = 0 km/h where the half of the suction side of the fan was covered by a flat plate. The results showed that the fluid pressure and the aerodynamic force increases with the free stream velocity. Asymmetric pressure and fluid force distribution was identified when suction side of the fan was partially covered.

  • Nikolett Németh :

    There is a great variety of foods eaten. It is obvious that foods play a very important role in the daily lives of individual nations. Foods and meals, however, serve not only the living, but also fulfil other functions in the given society. For example, food expression may be part of a social class, reveal income conditions, and express identity. The investigation was carried out on the topic by a qualitative method, in the form of an in-depth interview. The interviews were conducted by master students of the Szent István University in the framework of Multicultural Management subject, with non-Hungarian origin. A total of 65 in-depth interviews were conducted between 2017 and 2018. Interviewees were members of 22 nationalities. During the investigations, the main questions were: What type of food do you consume the most? What factors do you take into consideration when choosing foods? What differences do you find in the habits of the different ethnic groups, especially with regard to their eating habits? Most of the interviewees are interested in compare their diet and cultural traditions to other nations’ and prefer local foods. The study proved that eating habits in Hungary have an impact on the eating habits of foreign students, and they change them in several elements. The study found that dietary choices are a complex decision that has a significant environmental and social impact but need to say, thanks to the strong cultural background the students can keep their sustainable eating values in abroad.

  • Titanilla Oravecz ,
    Ildikó Kovács :

    Aside from honey’s sweet and distinctive flavor, it can provide various human health benefits, which makes its market value favorable compared to those of other sweeteners. In the study, the purchase decision making process is examined through sensory experiments. The results are based on sensory analysis of 600 adult consumers, which show that, consumers’ demand for honey varies significantly according to the flavor, aroma, color, texture and price. The geographic location of the honey’s production and the product packaging are key factors for some consumer segments. Sensory differentiation and the evaluation of honey quality are different in the analyzed consumer segments, which are described in the study.

  • Dóra Szalay ,
    Szabolcs Kertész ,
    Andrea Vágvölgyi :

    Current forestry laws and regulations are not applicable to woody energy plantations. The cultivation technology used in these plantations differs from ones used in conventional forest management; thereby, specific legislation to regulate cultivation in woody energy plantations is required. Hungary passed its first regulations for woody energy plantations in 2007. The legislation addressed permitting, range of plantable species, planting procedures, cultivation, and plantation harvesting. The legislation overregulated coppice technology and only targeted roundwood energy plantation. The legislation does not mandate forest site surveys and its related expert opinions despite their importance in plantation establishment, particularly regarding tree species selection. The latest legislation, which improves earlier deficiencies and prescribes planting-execution plans for all plantations, came into effect 2017. Another important change is the industrial purpose categorization of woody plantations, which appeared beside coppice and roundwood energy plantations. In addition to raw material production, this type of plantation also increases the carbon sequestration of agriculture. The availability of financial resources heavily influenced plantation area size and planting intensity over the years. Investigating plantation tendencies provides an opportunity to identify forms of support that play an important role in creating the conditions for rational land use. Our research presents the effects these changes in legislation and financial support have had on energy plantations.