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Mechanical Testing of 3D Metal Printed Stainless Steel Specimens
7-13.Views:90Additive manufacturing (AM) is a cutting-edge production method, which has come a long way since its first introduction in the ’80s. Back in the days its usage was very limited to stereolithography, and was only able to make weak structures, so it only worked for visualization. Four decades later it is one of the leading research fields in production areas, because of its flexibility and its ability to make almost any complex geometry. However, no matter how powerful it is, it is not omnipotent, there are certain size and shape restrictions even this method must apply to.
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Potentiodynamic Study of the Effects of Nickel on The Electrodeposition of Zinc from Chloride Media
15-24Views:106Abstract. The potentiodynamic experiments of the nickel effects on the zinc electrodeposition have been done to understand the impact of Ni impurities on the electrowinning of Zn from spent pickling liquor. The nickel chloride solutions of Ni concentrations 90 and 1 g/dm3 were used as the electrolytes. The latter was also mixed with 90 g/dm3 Zn in the experiments. All the runs were carried out at room temperature with 40 mV/s continuous polarization speed and with 1/s sampling rate. It was observed that nickel electrodeposition from chloride media containing 90 g/dm3 Ni started with the generation of hydrogen bubbles, entirely blocking the cathode surface. Only a slight current development was observed until the polarization potential ~ -0,8 V. The visual observation showed bubbles also formed at the anode, which may represent chlorine and/or oxygen evolution. While, in the electrodeposition of nickel with only 1 g/dm3 Ni concentration in the electrolyte, metal deposition was hardly observed, but visible hydrogen bubbles constantly blocked the cathode surface. A similar tendency was observed in the mixed-solution electrolysis cell; the initial tiny bubbles accumulated at the cathode surface more than in the pure Zn solution. The enhancement of H2 evolution indicates how nickel deposition may contribute to the loss of useful current in the process of Zn electrodeposition. The mass of nickel deposited from the mixed solutions significantly decreases as the Ni concentration decreases in the electrolyte, while the mass of deposited zinc is relatively constant. It means that the purity of the produced Zn is appreciably higher – with respect to Ni – if nickel is efficiently eliminated from the solution before electrowinning.
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Implementation of Lean management Practices in Azerbaijan (on the Example of a Private Company)
30-40Views:76Organizations are facing crucial modifications as global market and conditions change day after day. To keep up with fast changing realities, it’s important to apply innovation decisions to the current stage of organizations. Lean management consolidates tools and techniques to revert from traditional way of operating to the new human oriented one. In the carried-out research its outlined, human resources management plays a big role in spreading and supporting lean initiatives. It was suggested that, Lean and Human resources management are compatible and should work together to obtain sustainable success by implementation of an innovation approach such as Lean. Both lean management and human resource management focus on the same goals with different methods in terms of control of businesses. All positivist approaches and practices are included in these approaches and practices, which are developed with a focus on the interests of the community, in order for the process to be concluded positively. The employee-centred management approach of human resources management is crucial to lead and maintain good environment in the teams. For this reason, in the lean management philosophy, it is aware that the corporate structure has responsibilities in terms of training the employees, eliminating their problems and supporting them in struggling with the responsibilities they undertake. This paper is quantitative, online survey has been conducted with employees of a private company in Azerbaijan and results were analysed in statistical analysis software SPSS and relevant suggestions and recommendation were given for reorganization to enable lean friendly environment on a sample of the given company.
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Development and Characterization of Sisal Fiber Reinforced Polypropylene Composite Materials
348-358Views:337In most of the developing countries, plastic polypropylene is not fully recycled and converted in-to use after it is once used. Sisal fiber is also widely available in different developing countries like Ethiopia. Adding this two materials and developing automotive interior part was taken as a primary motive for it reduces cost and is environmentally friendly. Thus, the main purpose of this research is to develop composite material from natural fibre (sisal fiber) reinforced with recycled plastic waste (polypropylene) for interior automobile accessories specifically for internal door trim panel application. This research examines effect of fiber length, fiber loading and chemical treatment of fiber on the physical and chemical properties of the sisal fiber reinforced polypropylene (SFRPP) composite material. The waste polypropylene and the treated and untreated sisal fiber with variable length and weight ratio (fiber/matrix ratio) were mixed. Flammability of sisal fiber reinforced Polypropylene (SFRPP) composites material was examined by a horizontal burning test according to ASTM D635 and chemical resistance of the sisal fibre reinforced PP composites was studied using ASTM D543 testing method. The result on the flammability test shows that treated fiber has lower burning rate than untreated fiber and decreases with increase in fiber length and fiber loading. The resistance of the composites to water has increased as the fiber length increases and decreased as the fiber loading increase. Generally, SFRPP composite is found to have better resistance to water than NaOH and H2SO4 and treating the fiber has brought considerable improvement on chemical resistance of the composite. Fiber loading and fiber length has positive and negative effect on the flammability of the SFRPP composite respectively.
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Synthesis of Polylactic Acid (PLA) by Polycondensation Method
286-293Views:305The 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.
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Optimization and Analysis of Structure about Lifting Device of Logistics Sorting
425-431Views:147The 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.
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Combustors with Low Emission Levels for Aero Gas Turbine Engines
503-514Views:317The 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.
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Exhaust System Muffler Volume Optimization of Light Commercial passenger Car Using Transfer Matrix Method
132-138Views:172Nowadays, 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.
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Analysing the Possible Connection Between Dark Triad Personality Traits and Ethical Attitudes of University Students
57-67Views:304In 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.
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Safety Index Based on Geometric Probability Is Proposed to Represent the Uncertainty of Soil Parameters for Spread Foundations
43-52Views:94The 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.
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Simulation of Hot Rolling by Cellular Automata
190-195Views:184Our 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.
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Investigation of Aluminum Dross as a Potential Asphalt Filler
445-451Views:91There 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.
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The Efficiency of Intellectual Capital as a Crucial Factor of Innovation
419-428Views:231In 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.
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Review on Construction Procedures of Driving Cycles
266-285Views:269The 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.
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The Effect of annealing temperature on corrosion resistance and microstructure of Zr-Sn-Nb-Fe alloy
420-424Views:101The 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.
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The Role of Stocks in the Supply Chain
515-526Views:1079Az ellátási lánc teljesítményét nagymértékben befolyásolja a szereplők készleteinek összetétele, nagysága, rendelkezésre állása. A végső fogyasztókért vívott versenyben kiemelt szerepe van a kiszolgálási színvonalnak, hiszen az ellátási láncok ugyanazokért a fogyasztókért vívnak versenyt, és a fogyasztók döntése leginkább e két tényező, mint a készlet nagyága és a kiszolgálás minőségétől függ. A tanulmány a kkv-k logisztikai problémáit feltáró kutatás része, melynek célja rávilágítani a jellemző nehézségekre, és azokra a kihívásokra, amelyek legtöbbször elkerülik a logisztikai- vagy ellátási lánc vezetők figyelmét. A fejlődő kkv méretű vállalkozások versenyképessége - ami magába foglalja a költségek nagyságát is, kapcsolódva a K+F tevékenységhez vagy vállalat növekedéshez – a lekötött tőke mértékével arányosan változhat, melynek jelentős részét képezik a készletek. A kutatásban résztvevő vállalat, a Diego Kereskedelmi Kft. készletezési politikáján keresztül kerül elemzésre a készletek összetétele, illetve a velük kapcsolatos kockázatok, illetve félreértések. A tanulmány célja továbbá a helyes megoldások elősegítése, melyhez szorosan kapcsolódik (az itt tárgyalásra nem kerülő) Lean megoldások támogató szerepe.
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Neutral Inhomogeneity in Circular Cylinder Subjected to Axial Load on its Lateral Boundary
35-42Views:132In this paper we consider the problem of single circular elastic inhomogeneity embedded within a circular cylinder whose curved boundary surface is subjected to surface traction acting on axial direction. We investigate the displacement neutrality of the coupled system of host body and inclusion. Neutral inhomogeneity (inclusion) does not disturb the displacement, strain and stress fields in the host body. The deformation of the considered inhomogenneous cylinder is antiplane shear deformation.
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Development of Analysis of Loss Sources of Vehicles
733-737Views:151Vehicle fuel consumption can be significantly influenced by various types of losses such as loss from bearing, aerodynamic drag and rolling drag. It is important to highlight that fuel consumption reduction can be only achieved when those losses are reduced that are induced during the operation.
The aim of our work group is to define the calculation method and the magnitude of the losses of the vehicles. These parameters are intended to be serve as input parameters for future energetic modelling of vehicles.
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Utilisation and Quality Management of Power Plant Fly Ash
329-337Views:157Over the past decades, both the residential and industrial energy demand has increased due to the continuously growing consumption and production. As a large share of the electricity is still produced using fossil fuels, the utilisation of the by-products is a contemporary and pervasive issue. Fly ash is generated in large quantities in coal-fired power plants and has been proven to be an appropriate raw material for various industrial uses. Among others, it is applicable as an additive and lightweight aggregate in the cement and concrete industry, can be used for CO2 sequestration, glass foam production, catalyst production, or as a base material for geopolymers, as well. Geopolymers are inorganic polymers produced via the reaction between solid alumina and silica containing or alkali silicate materials in alkali media. Due to their numerous advantageous properties and wide variety of utilisation possibilities, research on fly ash base geopolymers became widespread topic. The quality of fly ash is determined by technical requirements, and the degree of quality control requirements depends on the final use. In certain fields of applications, standards and regulations have already been created to ensure the consistent quality of the final products made from fly ash, e.g. in the cement and concrete industry. There are various methods for fly ash processing, however, the methods to achieve the necessary properties are not standardised.
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Investigation of the Luxury Yachts Condition and Their Maintenance
95-105Views:129Surveying the condition of yachts and their maintenance is of great importance for their functionality and efficiency. Finding the right approaches, expertise at different levels, design benchmarking are essential for all yacht maintenance and security, resulting in crew and passenger safety. This report presents an evaluation and expertise in a real environment and documentation of decision-makers for the strength and functionality of a luxury motor yacht. For a good understanding of the problem, detailed photographic material has been documented showing in detail the required technical corrections. The research would be of interest to a wide range of yacht design and industry professionals, academic and research representatives, yacht users and all interested stakeholders.
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Why do not people attend football matches in Hungary?
11-22Views:253Both international and domestic research on passive sport consumption focuses on the motivations of fans. However in Hungary, unlike the examples of North America and Western Europe, we have to look for answers to the question of why people do not go to football matches. In order to find an answer to this question, we conducted an online survey with a number of items of 347 people. For the latter a scale measuring absence from sport consumption was used and the reliability of the scales was tested by Cronbach's alpha calculation. After our principal component analysis, we developed 5 internal and 5 external factors, on which we conduct hypothesis test along demographic and sports consumption variables. Based on our results, we have established that, contrary to public opinion, the low number of spectators in Hungarian football matches is not only and primarily due to unsucces and the low quality of matches. Our respondents are mostly kept away from stadiums by football-related government measures, as well as by preferring to participate in other recreational program opportunities.
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Rotational molding of plasma treated polyethylene/short glass fiber composites
103-108Views:141Rotational molding is a manufacturing technique for producing 3D hollow parts by adding plastic powder to a shell-like mold and rotating the mold while heating it with the powder. In contrary to the injection molding all the process operates at atmospheric pressure which makes reinforcement of the rotomolded product difficult. In this paper plasma treated PE and short glass fibers were dry mixed and used to produce composites by rotational molding process and characterized in terms of morphology and mechanical properties.
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Perceived Barriers to Youth Entrepreneurship in Pakistan and Hungary
382-391Views:119Entrepreneurship brings enormous benefits. It generates employment and helps in social and economic development. Ventures created through the youth entrepreneurship have enormous benefits. They generate employment, reduce poverty and unequitable distribution of wealth. These ventures do also help in social, economic and technological development. However, the youth faces several barriers to entrepreneurship. This study explores the personal & psychological, family related, institutional & regulatory, cultural & social, financial and market & knowledge barriers faced by the youth of Hungary and Pakistan. Qualitative research methodology was applied. Interviews at micro and meso levels were conducted from the young entrepreneurs and university professors of Pakistan and Hungary. Results indicate that Pakistan and Hungary have almost similar levels of Personal & Psychological barriers, however, the fear of failure is higher in Hungary than in Pakistan. Family related, cultural & social and market & knowledge barriers are higher in Pakistan for the youth entrepreneurship than Hungary. Institutional & regulatory and financial barriers are at medium levels in Pakistan. For Hungary, these are at low levels. The study has important implications for researchers, academicians, policy makers and for the young aspiring entrepreneurs.
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Interchange of Heat in Saw Disc Body During Cutting
488-494Views:101The paper presents the experimental results of a research aimed at the distribution of the temperature on the circular saw blade body. The temperature was measured at two distances from the centre of the circular saw blade body (70 mm, 140 mm) by means of an infrared thermometer. Two circular saw blades with the diameter of 350 mm and a variable adjustment of the body (with slots and without the coating, with both slots and coating) were used for the longitudinal sawing of the spruce wood (Picea excelsa) with the thickness of h = 37 mm. Feed speeds ware vf1 = 14 mpm, vf2 = 17 mpm and vf3 = 20 mpm. Cutting revolutions n = 4100 /min. were constant. The measured temperature was in the range from 21 °C till 27 °C. The highest measured temperatures were recorded on the circular saw blade with the slots and coating.
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A Debreceni Egyetem Gazdaságtudományi Karának Controlling és teljesítménymenedzsment szakirány kurzusainak értékelése
100-107Views:470It is of major importance for the Faculty of Economics and Business of the University of Debrecen to become familiar with the opinion of students about the education carried out at the University, therefore particular attention is given to the feedback of students related to education. Measurement and evaluation/reviews serve multiple purposes. Students may – if explicit written consent of the lecturer is provided – get to know the opinion of their fellow students about each course, lecturers may receive feedback about the reputation of their courses, the University and Faculties may acquire information about the overall opinion of their students about the training. Feedback is basically suitable for supporting the work aimed at the improvement of training quality. In the scope of present study the reviews submitted by the students of the Controlling and performance specialisation within the Management and Organisation course are introduced.
