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Ultrasonic Powder Atomization for Additive Manufacturing
69-75Views:164The following article presents a special case of metal powder production, ultrasonic metal atomization. In this case, ultrasound technology is based on the capillary wave phenomenon. We verify the suitability of the produced powders for 3D metal printing with various tests. In the case of prints with a metal powder bed fusion (PBF), the properties of the raw material of the powder are extremely important. The main results of the tests carried out in the article (SEM images, EDS composition analysis, sieve analysis) were described.
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Why Public Sector Projects Fail or Succeed in Pakistan- A Model for Evaluating Impact of HR Management Practices on Project Success
77-90Views:319Employees are the most important assets of an organization. As quality human resources become scarce, companies need to pay more heed to the satisfaction and motivation of their employees. If employees are motivated towards work, then it is likely to yield better results. This study will examine the role of Human resource management (HRM) practices upon New product development (NPD). NPD involves technical, marketing, and financial risks organizations undertake for developing new products and services. Effective project planning and control are valuable for decision-making. The analysis of the impact of HRM practices on NPD, project success, and organizational benefit is based on data collected using a cross-sectional design via a survey questionnaire. The questionnaire consisted of items related to HR practices, New product development, Project Success, and Organizational benefits adapted from previous studies. Respondents working in 10 large-scale public sector projects executed by National Database & Registration Authority, Pakistan were selected for the study. Therefore, the results of the study can be generalized to similar projects executed by the public sector in Pakistan. From the findings of data analysis, it has been concluded that there is a significant association between HR practices and project success, but no significant relationship has been established between new product development and organizational benefit. Therefore, it can be concluded that HR management practices have a significant impact on public sector project success in the case of Pakistan.
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Analysis of Structural Strengths Applied the Cableway Group
62-66Views:67This paper will present the analysis of structural strengths for the cableway group. Three loading scenarios were analyzed. Each of these scenarios will be presented on the cableway group and explained with the intervening forces.
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Examination of preferences for pork meat and pork meat products among university students
131-141Views:178The purpose of this study was to examine the preferences for pork meat and pork meat products. The used sample (N=324) for the analysis came from the students of the University of Debrecen Faculty of Economics and Business. The survey was conducted by the form of online questionnaire. The results from data analyzes were based on descriptive statistics, cross-table and correlation analysis, Mann-Whitney and Kruskal-Wallis tests. Based on the results we can concluded that majority of consumers in the sample would be willing to pay more for hungarian and healthier products with less than 50%. Furthermore we can say that have a significant difference between men and women according all factors which used in analysis; have a significant difference between people with secondary and higher education according to perception of manufacturer/brand; have a significant difference between income level groups according to price and healthy eating.
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Risk Analysis of Food Retail Companies in Hungary’s Northern Great Plain Region
539-550Views:321Based on the financial ratios of analyzed companies we were performed a risk analysis, highlighting the degree of operational and financial leverages and the degree of combined leverage combining preceding ratios. We introduced a new aspect of the risk concept which began to spread in recent times. In the interest of to be able to analyse together cross-sectional and time series data, panel regression model was used. The panel regression is an extension of the multivariate linear regression interpreted as a multi-level model. In our study, the panel regression was used for analysis of food retailer companies, in the Northern Great Plain region's counties, in the period 2009-2014.
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Labour Economics - From the Technological Development Perspective
1-11Views:33The impact of technological advancements on the labor market and innovation processes is a critically important research area. The aim of this study is to examine the emergence and frequency of technological innovations in scientific publications, with a particular focus on the Journal of Labour Economics from 2000 to 2020. The research employs content analysis methods, searching for eight different terms and expressions related to technological development (e.g., technology, artificial intelligence, machine learning) across 1405 articles. The study also analyzes the number of occurrences and annual publication trends of these terms. A total of 9469 instances were identified, indicating that in 64,7% of the cases, at least one technological term appeared. An analysis of annual trends reveals an increase in the usage of certain keywords (technology, artificial intelligence, and machine learning). In a smaller subset of articles, only 1%, technological terms were mentioned at least 50 times. The results suggest that although the topic of technological development plays a significant role in labor market research, the frequency of its appearance and the depth of analysis vary considerably. The increase in the appearance of technological terms is predominantly observed in the fields of artificial intelligence and machine learning. These findings are specific to a single journal, indicating the need for further research involving other labor market journals to ensure representativeness.
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Material flows and stocks of a service company from Debrecen
313-321Views:234Over the past 25 years, many renowned scientists from a number of research institutes have developed a new research method, a new family of methodologies which is the MFA (Material Flow Analysis). The importance of MFA is given by the extent of excited material flows created by mankind. The basis of MFA's growing success is a radically new, interdisciplinary vision that requires collaboration between the natural and social sciences (ecology, thermodynamics, and economics), not only as an effective tool for examining material efficiency of production and environmental pressures, as well as the security of supply of the strategic material requirements of the system under investigation. In our article, we conduct an enterprise level analysis of the input and output side material flows and materials of a service company in Debrecen for 2018 using the MFA method. MFA indicators capture environmental pressures in a natural dimension, that is, in terms of mass, energy, or land, respectively, in terms of kilograms or tons, of the company's raw materials and their changes, or material inputs.
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The Analysis of the Seasonal Changes of Microbial Communities in the Activated Sludge of Small and Large Wastewater Treatment Plants
321-340Views:121In our research the seasonal changes of the microbial communities in the activated sludge of one large and two small wastewater treatment plants are observed and analysed. During the research, 14 months of data were processed. After the sample analysis and data processing, the research revealed the efficiency of the ecological system, and also showed the seasonal changes of the community structures. The results of the statistical analysis show, that the seasonality is less observable in the case of the larger system. Presumably, the larger bioreactors have more stable microbial composition. In addition, we searched for more connections between the components of the ecological system, the changing in the weather, and also in the efficiency in the process for treating wastewater.
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Co-authorship Network Analysis
76-84Views:155The methodological basis of research on networks is given by graph theory. During the network analysis we work with a big data population and we are mainly analysing the relationships of the actors, which can be visualized with the graph network. The analysis of social network is becoming more and more popular in academic life as well. Most of the co-authorship networks are built around a number of prestigious people who manage their own network as a central player creating cliques.
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Use of ANSYS Software for the Acetabular Cup Structure Analysis out of the Hip Implant
1-6.Views:347Modelling the hip implant has been one of the most important researches over the past few decades. In addition, using the ANSYS software for this purpose is well-known procedure to understand the real reaction of the hip implant parts during the daily life of the installed part. This study is to focus on the practical part of the use of ANSYS software to analyse the performance of the hip implant through the feature of structure analysis available in the ANSYS. The research applies the static loads behaviour only with the help of the static structural analysis to view the advantages and the disadvantages of every design, which helps us estimate the implant’s behaviour. The study investigates the optimization of the acetabular cup using the lattice optimization along with the infill option available in the ANSYS software in order to optimize the stress and the fixture of the cup inside the pelvis.
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Mechanical Design and Finite element Analysis for Acetabular cup
23-35Views:118Hip replacements typically consist of a four-part piece. Our research will focus primarily on the acetabular component. Several different types of materials can be used when creating a hip replacement implant ranging from plastic to titanium. Different materials are used to accommodate for allergic reactions or circumventing potential health risks. Aside from the material, the size of the components plays a factor in terms of durability; a larger diameter head might avoid dislodgement though it could increase wear and tear on the stems through constant friction. A patient’s force applied to the hip replacement is usually measured through a number of physical assessments. Finite element analysis (FEA), a computer-based method of data observation, allows for us to accurately simulate hip forces and their impact on the hip replacements. Through this, it becomes easier to predict and calculate the performance of specific designs. Generative systems can also be used to support performance analysis and optimization through assessing a multitude of cases, many of which apply in real-world scenarios. By applying both systems, we designed and modeled an acetabular cup that when measured decreased the mass from 129 grams initially down to 52 grams, a 60% decrease in total mass. Furthermore, the design we created lessened the trauma on the piece through distributing force across the entirety of the piece rather than specific segments only. This shows an increased durability and life expectancy when compared to usual acetabular cups.
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The Comparative Analysis of the Microbial Communities of Activated Sludge
87-101Views:147The composition of the microbial communities in the activated sludge was thought mostly chaotic and unpredictable, but due to the new studies and breakthroughs in the past decades, now it is known that specific, accidental and non-accidental factors are responsible for the structure of the microbial community. The aim of the study is to compare the microbial communities of activated sludge of one large and two small wastewater treatment plants. During our research 14 months of data were processed. After the sample analysis and data processing, the diversity and seasonal changes of the community structures revealed. The results of the statistical analysis show that the larger system has more diverse community structure.
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Statistical Evaluation of University Student’s Motivation and Personal Competency with Principal Component and Cluster Analysis
365-374Views:204The aim of the research is to do a statistical evaluation of agricultural and rural development engineer student’s motivation and personal competency. It sums up the late generation Y’s characteristics and challenges. To be a successful, graduated employee, not only the skill is needed but the personal competency as well. Altogether, 121 filled out questionnaires were collected from the students which were the prime source of the research. They had to evaluate influential factors to their motivation level and competence. The database was analyzed with descriptive statistic methods, principal component and cluster analysis. Studying the personal competency, five different factors were divided based on Belbin’s team roles and four clusters. The four clusters were established by the five factors. Analyzing the student’s educational motivation four different components were divided: the need of performance, social entertainment, the benefits of learning in the near future and the reach of the financial freedom. Based on the four components, generating clusters was not possible due to the significance level of the K-means cluster analysis because it was higher than 0,05 in every grouping variables.
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Defect Analysis of Bearings with Vibration Monitoring and Optical Methods
1-12Views:166Diagnosis of bearings with advanced methods gained remarkable roles in the previous years. This article focuses on the manufacturing defects and methods to reveal and classify them. During manufacturing several faults could emerge because of the grinding operation, tool wear and chatter vibration. Inproper handling of the bearing parts because of the collosion to each other and the storing box that causes deformation. To reveal these problems several methods are applied in industry. For deeper surface analysis nitric acid can be used to initate the finished surface of the roller then natrium-carbonate that nautralize the elements. Vibration analysis in its standard Fourier form is not a new achivement but other mathematical tools could be applied to condition monitoring such as wavelet transform. It is an efficient tool for analyzing the vibration signal of the bearings because it can detect the sudden changes and transient impulses in the signal caused by faults on the bearing elements. In this article five different wavelets, Daubechies, Gaussian, Coiflet, Mexican hat, Meyer are compared according to the Energy to Shannon Entropy ratio criteria to reveal their efficiency for fault detection.
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Financial Performance Measurement with the Use of Financial Ratios: Case of Mongolian Companies
20-32Views:292The aim of this paper is to examine the efficiency of Mongolian 100 public companies listed on Mongolian Stock Exchange (MSE) which are divided into 6 major sectors. This study conducts the performance of companies in terms of profitability by using three different output variables i.e., revenue, pretax profit and ROA (Return on Assets). In the beginning of this research, nine variables which are connected with profitability are chosen as output variables, while 24 variables expressing growth, financial structure, solvency, and turnover together with some fundamental financial data are chosen as input variables. 10 variables out of 24 input variables, which determine the financial structure, solvency, and profitability, are chosen as input variables based on the calculation of stepwise regression analysis. Stepwise regression, multi co-linearity analysis are made by SPSS and DEA (Data envelopment analysis) is evaluated by benchmarking package in R excel statistical program covering the period of 2012-2015. This paper uses the input-oriented version of DEA based on financial ratios and some crucial components of a financial statement. The results of DEA show that food and grocery sector was the most efficient, and mining sector was at the second place by its efficiency, while agriculture and service sector were the worse than other sectors.
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Investigating the Effects of Active Cooling in 3D Printing
39-47Views:1333D printing is an increasingly widespread manufacturing process. With the development of machines and materials, the technology is becoming more accessible and easier to use. However, the technology's specificities mean that it requires knowledge of manufacturing technology. In some cases, it is necessary to solidify the freshly deposited layers as soon as possible in the event of large overhangs. This can be achieved by active cooling, which in turn can affect the material properties of the part. This research investigates the effects of active cooling during production.
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Thermoelastic Problems of Multilayered Spherical Pressure Vessels Subjected to Axisymmetric Loading
106-115Views:111This paper deals with the linear thermoelastic analysis of functionally graded multilayered spherical bodies subjected to constant mechanical and thermal loading. The temperature field is arbitrary function of the radial coordinate, the material properties and the radial body force vary according to power law functions along the radius of the sphere. An analytical method is presented to calculate the displacements and stresses within the multilayered spherical body. The method is expanded to tackle the problem of spherical bodies made from radially graded materials with temperature dependent material properties. The results are compared to finite element simulations and other methods.
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Changeable requirements & Answers With a dynamic system in order to continual improvement of the environmental performance of a rubber industrial big company
81-90Views:110The topic of this article is the analysis of the changeable environmental requirements for the Environmental Management Systems (EMS) of the companies. The strengthened environmental criteria of the 21st century creates new challenges for the participants of the business sphere. In order to satisfy the criteria of the stakeholders, it is necessary to build out a - by the top management - preferred and proactive EMS that can contain also a life cycle thinking method. This logic is supported by the new ISO14001:2015 standard, too. In the first part of the article the stakeholder conception and the new standard model is presented based on literature analysis. The second part of the article presents an environmental management tool developed by a multinational, tyre company. The model combines the stakeholder conception, the requirements and the life cycle assessment (LCA) in order to respond to the new environmental management challenges. The last part of the article closes with the new development possibilities of the presented environmental management tool worked out by the author.
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Testing the Sametest-effect in a BSc-level Business Communication Course Examination
10-15Views:69Using secondary data, we empirically examine two biasing effects that may arise in the written evaluation of large groups of students. Suppose the students take the examination in consecutive groups, and we wish to avoid the distortion caused by tests of different difficulty. In that case, we can decide to use the same examination questions. However, the danger of the "same test effect" arises, according to which the group writing later can perform better if it receives information from the examinees in the previous round. Using the same examination tests cannot be recommended if that effect is significant. Another related potential phenomenon is the "revealed sameness effect". Accordingly, if the examinees are aware of the repetition of the questions, it significantly increases the scores of the following group. We tested these phenomena using the data of a three-round written examination. A previously published analysis of a larger sample found that the "same test effect" can be expected if the students decide in which round they take the examination. Since it was possible to freely register for the examination rounds for the assessment analyzed in this study, we assume that the "same test effect" will be significant. Based on the literature, we also expected that the "revealed sameness effect" would occur in the third round. The performed linear regression analysis (N=77) only found some weak evidence for the 'revealed sameness effect' but not for the 'same test effect'.
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Investigation of the Eigenfrequency of the Bending Vibration of the Beam Clamped at Both Ends Around the Principle Directions of Inertia Based on a Single-Degree Freedom Model and a Finite Element Method Analysis
69-79Views:184In this study, we have dealt with the calculation methods of the eigenfrequencies associated with the bending vibrations of rectangular-shaped beams clamped at both ends. Said eigenfrequencies were determined analytically in the single-degree of freedom model of the beam and the case of the three-dimensional solid and three-dimensional rod models by finite element modal vibration analysis. We presented the calculation method of the characteristics of the analytical model and then calculated the eigenfrequency for a concrete example. We have described the concept of modal characteristics, and in the following, we have determined its natural frequency based on the solid-beam and rod models of the former beam. We calculated and compared the solutions belonging to the models recorded in different ways in 11 additional cases of the presented methods.
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Knowledge of Control Methods and their Application in the Practice of Small and Medium Enterprises in the Northern Great Plain Region
441-452Views:368Like large companies, the small, and medium-sized businesses need also all the information to ensure the efficiency and effectiveness of their business by making sound management decisions. Compared to large companies, SMEs have significant development potential, which can be created in part by the companies themselves, possibly through the introduction of new-modern management - business administration methods or economic policy measures (= targeted and efficient support system), which, by stimulating R & D & I processes, serves to increase competitiveness and contribute more and proportionally to domestic GDP and exports. The analysis presented in the study covers the controlling knowledge of the leading SMEs of the Northern Great Plain Region, the conscious or unconscious application of controlling tools, the assessment of succession, customer and supplier valuation and certain areas of managerial accounting. Overall, it can be concluded from the small sample size that the use of controlling tools is proportional to the size of the business, but nevertheless, many mid-size business executives do not require the collection and analysis of insider information that could explicitly help decision making for example through advanced costing procedures.
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Introduction to Design and Analysis of Torsional Vibration Dampers in Vehicle Industry
310-324Views:323The crankshaft of today’s internal combustion engines with high performance output are exposed to harmful torsional oscillations originated from the unbalanced gas and inertial forces. To avoid the fatigue damage of engine components, caused by the undesired vibrations, torsional vibration dampers can be applied. Viscodampers are one type of the torsional vibration dampers, which operational fluid is silicone oil. For cost-effective R&D activities and production, finite element and finite volume numerical discretization methods based calculation techniques must be involved into the engineering work supported by the modern computer technology. The aim of this paper is to provide an insight into the multidisciplinary design and development process of visco-dampers in vehicle industry applications. Four different examples as structural, fatigue, CFD analyses and structural optimization have been introduced in the present work. It turned out from the static structural and fatigue analyses, that the investigated damper has safety factor over the limit for both static structural and fatigue analyses, so it is suitable for the given load conditions. In the structural optimization process 34.36% mass reduction has been achieved. According to the coupled fluid dynamic and heat transfer simulations a rather stagnating air zone evolved between the engine and the damper during the operation, which can cause efficiency reduction of cooling fins mounted onto the housing. In light of the numerical results, the suitable damper position has been determined for the highest heat transfer.
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Finite Element Analysis of Cellular Structures Using Ansys
197-204Views:221Additive manufacturing (AM) is a process in which the product is composed of overlapping layers of a material that is added using devices such as 3D printers. Its process has been evolving for decades and nowadays it can be used for several applications and with different materials. One modern usage is for medical and dental purposes. Since it became possible to print metal, it has been a good solution for bone implants, once it must be done with biomaterials and can now replicate the bone structure, for that unit cells should compose the implant. Both conditions are now possible to be achieved by AM, and the current study will analyze, using finite element method, the possibilities to create specimens for tests which the final product would result in a 3D printed bone implant.
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Építőipari kockázatok rétegei = Analysis of construction risks of layer
92-101Views:122Risk and uncertainty are subjects of philosophic and theoretic discussions long time ago. Both concepts have the intention that nature and effects of future happenings have to be analyzed and forecasted. Difference is though that analysis is possible by different means. Uncertainty is frightening and hard to be analyzed. On the other hand, risk is better served by data, easier to find a methodology that makes it a more acceptable and manageable object. Theoretic part of the article states that risk and uncertainty entitle a risk spectrum. The next statement is that this spectrum has layers piled on one on the other, from which risk and uncertainty are the ones on the sides.
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An Analysis of the Leisure Preference System of Students with Disabilities in the Light of a Study
98-115Views:675With the increase in the number of disabled people and people with disabilities, research on the target group of people with disabilities has gained momentum in recent decades. Research is very diverse, looking at the labor market situation of people with disabilities, their leisure-time habits, or the factors that support and inhibit their sport.
In our questionnaire research, the leisure and sporting habits of children with disabilities aged 8-18 are described and analyzed (N = 639). Data were processed with spss software, where basic statistics and contextual analysis were performed. The results confirm that passive activities (TV, listening to music) dominate the leisure activities of children with disabilities. Sports consumption (active and passive) was more prevalent among male respondents and less prominent among girls. In the motivation of sports, besides improving the state of health, entertainment and company appeared.
