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  • Application of Additive Technology in Precision Casting
    43-56
    Views:
    368

    In this paper the surface of the prepared test specimens had been examined with light microscopy and surface roughness measurements. In order to improve the surface smoothness of PLA specimens, application of ethyl acetate was required. After this surface treatment, microscopic images were taken again. The melting and decomposition temperatures of the materials had been determined using derivatography. The chosen method was precision casting with gypsum molding. Also, the plaster molds had been burnt out according to the predefined melting and firing diagram. The measurement series shows that the samples produced by 3D printing can also be used in the field of precision casting. They provide greater freedom of design, more sophisticated pieces, and prototypes can be finished in a shorter amount of time.

  • The Possibilities of Additive Manufacturing in Medical Use
    246-253
    Views:
    247

    Additive Manufacturing has been invented in 1981 at the University of Texas, and to this day it has grown to be the most versatile and promising manufacturing technology in the market, both the industry and health care system has noticed this. Additive Bio-Manufacturing (ABM) techniques, which can be used in health care, are highly in demand, and researches have been going on to make these technologies safer and even more versatile. For more utilization and versatility, special attention is required to develop new materials which can help in increasing the service life, bioactivity, cell growth along with the desired mechanical properties, and to find the right manufacturing parameters for creating optimal products. The aim of this review is to present the available main Additive Manufacturing technologies, and particularly the biomedical usability of Additive Manufacturing.

  • Connection Between Human Excreta and Global Warming
    139-154
    Views:
    332

    Our study would like to draw attention to an insufficiently investigated question: how human excreta and its different treatment methods are related to climate change. Human excreta is part of the biological cycle. Its CO2 content gets released to the atmosphere to some degree according to the treatment methods used. 40 55% of faeces’ and 11-17% of urine’s dry matter content is carbon (in the form of organic compounds). According to this, approximately 21-57 g/person carbon bound in organic compounds is produced daily, which means an emission of 58-183 million tons of carbon in the world annually in the form of human excreta. The environmental load of the widely spread flush toilet based water infrastructure is significant. However, neither the degree of CO2 emission caused by collection and treatment of waste water, nor wasting of organic and nutrient content of excreta are properly studied. Our study highlights the emission of CO2 caused by the energy demand of sewage water collection and treatment, by the oxidation of organic compounds of human excreta and by burning of methane produced as a result of anaerobic treatment of waste water sludge. Finally the possibility of utilization of human excreta by direct composting is presented, which technology has not significantly spread in the world yet.

  • Security and Risk management of Intelligent Integrated Institutes
    74-84
    Views:
    250

    The intelligent households are getting more and more popular beside the intelligent technologies. With all the advantages that this can provide, it brings the security risk of the information technology as well. We must deal with those dangers. We have to determine the risks so that we can make proper precautions. This article gives an effective guideline to achieve safety.

  • Engineering Spatial Ability and Spatial Geometry – Research Experiences 1.
    383-387
    Views:
    214

    Spatial visualization skills have an important role in teaching and learning of engineering studies. Many studies have shown that there are correlations between various measures of spatial skills and performance in particular Science, Technology, Engineering and Mathematics (STEM). Many engineering students have problems with imagining a spatial figure and therefore to solve the spatial geometry exercises, so development of spatial ability is very important. We have developed special tools and worksheets for development of spatial abilities

  • COVID-19 Pandemic Impact on Employees’ Physical Activity
    72-84
    Views:
    983

    Globalization and the recent explosive development of technology have significantly changed people’s lifestyles resulting in an increase in the number of people living a sedentary lifestyle. COVID-19 pandemic has exacerbated the situation and created an unprecedented situation in the world. In the present study, we investigate changes in the physical activity and sedentary behavior of adult workers caused by the coronavirus epidemic. In our online cross-sectional research, we used snowball methodology. The target group of the survey was adult workers. 108 people filled in the questionnaire, the majority (73.1%) are women, the average age is 37.18 years and most of them have higher degrees (Diploma: 74%, PhD: 14%). The present study revealed a decrease in physical activity and an increase in sedentary time for the employees in our study. Despite respondents detected a decrease in their physical activity, an increase was reported in the proportion of online training participants. The majority of respondents partially, or totally switched to work from home during the pandemic, which may further increase their sedentary lifestyle. We did not find significant differences among the domain of work and leisure time or occupational physical activity patterns. The workplace is a great opportunity for promoting physical activity and reducing sedentary time in the adult working population, therefore it would be important for organizations, decision-makers and health professionals to work on the design of strategies to these goals.

  • Dependence of the Passive Force Fp From the Revolutions, back Engagement of Cutting Edge Ae, Working Engagement of the Cutting Edge Ap During Milling
    72-79
    Views:
    311

    In this contribution is analysed the force component of final force (passive force) by peripheral milling operation. Therefore, the main parameters that had influence to independent variable were revolutions, back engagement of a cutting edge ae, working engagement of the cutting edge ap. The article deals with the issue of milling in material AlMgSi0.5 (aluminium alloy). Specifically evaluates the force component with respect to change of revolutions (4000/min., 5000/min., 6000/min.), working engagement of the cutting edge ap (1 mm, 2 mm, 3 mm) and back engagement of a cutting edge ae (5 mm, 10 mm, 15 mm). The Alfaflex process fluid with 7% concentration was supplied in an amount of about cca 10 l/min.

  • Solutions of Warehouse Technology in Connection with Management Decisions
    1-10
    Views:
    243

    The aim of the study is to analyse the effect of management decisions on space utilization of warehouses through two companies’ example. The only way to make good decisions is to take into consideration the possible effects of changes. One of the tire manufacturing companies managed to improve space utilization, caused not only time but cost reduction. On the contrary, a bad decision of a household chemical factory induced enormous problems in the material flow.

  • Possibilities of the Reclamation of Wastewater in Small Abattoirs Combined with Rainwater Harvesting
    115-125
    Views:
    209

    The purpose of the study is to review the extent to which waste water from small mobile slaughterhouses can be reclaimed along with the basic cases and the purpose for which this can be realized. Keeping the criteria of sustainability in mind, I identify the possible and at the same time reasonable combinations of technology, highlighting and presenting in more detail those that include the utilization of waste water and the utilization of rainwater. I will describe the limiting factors - site features, environmental protection and health regulations - which are decisive in which alternative can be chosen during a specific installation.

  • Requirements for Multicultural Competencies Defined by a Focus Group
    44-56
    Views:
    360

    Globalization, the spread of multinational companies and the enormous development of information technology can lead to a new trend in employers’ requirements. However, being employed by an international company is a real possibility for any employee in any part of the world. Even if they do not have to work abroad, employees may have to function in a multinational environment in their home countries. A favourable combination of intercultural competencies is a key factor in the selection and development of employees. A possible way of measuring these competencies can be the Multicultural Personality Questionnaire (MPQ). First of all,on the employers’ part, it is important to clarify the exact requirements and competencies (dimensions) to be able to draw up an ‘ideal profile’. We prepared two versions of the MPQ (91-item; 5-dimensional) and used them to test employers’ requirements in the selection process regarding the dimensions of cultural empathy, open-mindedness, social initiative, emotional stability and flexibility. This study describes the results of a focus group interview, which took place in 2017, revealing the importance of multicultural competencies from the employers’ point of view and examining the conditions of the adaptability of the two questionnaires. We used the focus group method to find out in what conditions the questionnaires canbe used in a selection process. What possibilities and limits are therefor using the direct five-dimensional questionnaire? What aspects do we need to take into consideration in expressing and interpreting the requirements in the results of the test?

  • Modern Applications of Aluminium Foams
    14-21
    Views:
    481

    The implementation of aluminium alloy foam has more and more attention. Application of closed cell aluminium foam has made an impact in automobile and aerospace applications where crash energy absorption, vibration and weight reduction are obligatory [1,2,3]. The aluminium alloy foam is an advanced lightweight material providing high strength and stiffness at relatively low density. The technological use of aluminium alloy foam is difficult with the currently available technologies. In the case of open cell aluminium foams, the most common research areas for application are heat exchanger components, filters and sound damping elements [3]. The manuscript focuses on the manufacturing techniques of the aluminium alloy foams according to the application areas. First step is the investigation of the requirements for the application: what are the loads and the circumstances and why can we use aluminium foams. Second step is the knowledge of the producing methods of the foam or the component. And the last step is the investigation of the possible testing methods.

  • Building’s Constructions and Structures. Part I. The Classification of Buildings by Supporting Structures
    56-78
    Views:
    473

    In the paper we deal with the structures interpreted among the buildings constructions. In the present, first part we classify the buildings constructions by their functions. Two main groups can be formed. Analysing supporting construction group can be shown that the building can be well classify by supporting constructions. The classification based on vertical supporting constructions like wall and column gives fourelement classification: wall frame, column frame, mixed frame and frame without vertical supporting constructions. This classification is very simple. Take into consideration of the buildings technology of walls and columns there can be given a classification whit more elements. Different subgroups can be interpreted using connections of walls and columns with floor construction in the certain groups.

  • What Drives The Diffusion of AI Recruitment Systems in Swiss HRM? The Importance of Technological Expertise, Innovative Climate, Competitive Pressure, Employees’ Expectations and Contextual Factors
    42-84
    Views:
    653

    This study examines organizational, environmental, and contextual factors influencing the diffusion of artificial intelligence recruitment systems in human resources management within Swiss organizations. Based on a survey provided to 324 private and public Swiss HR professionals, it explores how some technology-organization-environment theoretical framework predictors' as well as innovative climate provided by organizations influence the three stages – evaluation, adoption, and routinization ­– of diffusion of this innovation. To do this, the following article is based on a PLS-SEM structural equation model. Its main findings are that technological expertise, innovative climate, competitive pressure, and expectations regarding future use of the tool by organizations working in the same field are directly linked to the spread of this type of AI tool. However, public-sector organizations are more reluctant about using this type of tool. This aversion can, however, be moderated by an innovative climate and the fact that the HR function plays an active part in an organization's strategic direction. This said, this article makes a significant contribution to the literature about the diffusion of emerging technologies in organizations.

  • Analysis of the Policy Background of Transport Related Use of Renewable Energy
    124-129
    Views:
    251

    The EU energy policy prioritizes the following principles: sustainability, competitiveness and security of supply and addresses the reduction of greenhouse gas emissions as a priority. The related EU policy (including the White Paper on Transport) outlines these principles, identifies goals and opportunities for action. At company level methodological guidelines and standard procedures can be used to assess the carbon footprint of the organization, to generate efficiency goals and to prepare action plans. In the Hungarian policy framework, a comprehensive National Sustainable Development Framework Strategy defines the basic principles for the analysis of the sectorspecific or regional strategies. Sustainable Energy Action and Climate Plans (SECAPs) integrate energy and climate issues and include interventions and improvements for the better use of renewable energy sources in transport at municipal level. As a summary it can be stated that exploration of the policy background would needed to influence the use of renewable energy sources for transport and definition of the development goals can help economic organizations to transform their mobility patterns and reduce related carbon footprint.

  • Effect of the Changes in Bulk Density and Granulometric Properties on the Strength Properties of the Moulding Sand Mixtures
    116-122
    Views:
    363

    Foundry technology uses a lot of several natural materials. Sands use for preparing mixtures whereby making moulds or cores. Sand is defined as a granular, refractory major portion of mixture (90 – 98% in dependence on used binder). Sand properties depend on it has chemical and mineralogical composition; mainly particle size distribution and shape of grains and its size and sand surface texture. A comparative measurement of two quartz sand with different surface quality was carried out. Greensand mixtures were prepared to measure their permeability, compressive strength and wet tensile strength. The strength of sand mixtures has two main components. One of them is the cohesion of the binder; the other one is the adhesion between the binder and the foundry sand. The aim of this research is to determine the ratio of cohesion and adhesion within the strength values.

  • Designing Aspects and Classification of Bearing Industry Box Handling Apparatus
    325-334
    Views:
    253

    It has been an accepted tendency in the industrial practice since the last third of the 20th Century to decrease the living labour demand of the manufacturing processes. One of the main tools of it is the automation of production. In the design, the construction and the programming of the developed automata, the results of electronics, informatics and mechatronics can be used. All of the scientific fields mentioned above undergo intensive development. By the application of the results achieved in the design of the applications, the monotonous, dangerous and tiresome work not requiring expertise can be assigned to machines. In the longer run, the application of the automata is beneficial also in financial aspect, since the costs of living labour are continuously growing, while that of the mechatronic and technological devices show a rather decreasing tendency. Reliability is also an important aspect. It is well known for everyone that a well-designed and programmed automatic device performs its task without mistakes. If there is any objection or breakdown, on the basis of the currently valid safety technology rules, the machine stops, does not trigger any damage and after its repair, work can be continued.

  • Parametric Programming Applied to the Optimal Production Structure in Determining
    375-389
    Views:
    241

    The agricultural planning often the question arises, how the different input (fertilizer, feed, irrigation, etc) from what to use on a production (land, animals) unit basis, and to what intensity. The input transformational efficiency experiments by setting analysis and evaluation. For example examined the nutrient replenishers fertilization experiments, the effect of nutritional values of the feed on the body weight gain, milk production in animal experiments. The input input efficiency to the external environment (weather, soil conditions, unexpected events), the technology used and the biological factors both influence. The farmer must be chosen in each sector, taking into account the magnitude of these inputs and environmental requirements. The economic optimum is usually trying to approach the sectoral level, which serves as the basis for future planning data. The mathematical programming models using relatively simply and quickly determine the optimal production structure. The models provide the specific resource requirements for, and the limitations of the objective function coefficients are calculated on the basis of sectoral. This becomes a deterministic model, and we can get the appropriate sectoral analyzes outstanding results of production structures. Therefore the relationships within sectors directly incorporate mathematical programming model and corporate interests placed above the interests of the industry to determine the intensity of the sectoral inputs. in their article a fertiliser application example, we present the production structure and the plant production sector fertiliser input of a time optimization, in which the fertilizer for specified sectoral relationships appear in the model objective function.