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Design of Experiments Application for Machining Process Analyse
257-265Views:266In this contribution are results from machining of the aluminium alloy by spiral router. The experiment was designed as full 3 - factors and 2-levels process and for evaluation of input factors to output parameters – Fx and Fy components were used Paret´s diagram and Lorentz´s line. The input parameters were: revolution speed (4000/min. and 6000/min.), working engagement of a cutting edge (depth of cut) ae (1 mm and 3 mm), back engagement of a cutting edge (with of cut) ap (5 mm and 15 mm) and down (climb) milling.
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Speed Variation along an Imposed Linear Trajectory, for Robotic Arms Motion
495-502Views:235The paper describes a method of speed (velocity) computation, named mixt profile, during a motion upon an imposed linear trajectory. The method assures an accurate positioning at the end of motion (movement), in a well determinate time lapse. The described method is linked with position vector computation, about a robotic arm.
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Investigation on Double Oxide Film Initiated Pore Formation in Aluminum Casting Alloys
141-153Views:595The most common, and in fact, the most deleterious defects of aluminum casting alloys are the so-called double oxide films or bifilms, which have a central role in porosity formation, as they can easily unfurl and inflate into pores during the solidification of the alloys. Sr addition is generally used in the foundry industry for the modification of the eutectic Si phase of hypoeutectic Al-Si alloys. However, Sr microalloying usually leads to an increased pore formation tendency. As bifilms are preferred sites for pore formation, it should be expected that Sr additions have a significant effect on the number and/or the structure of double oxide films present in the melt. In this work, the relationship between Sr-concentration and the susceptibility to pore formation has been investigated through the evaluation of melt quality of melts which had different levels of Sr. The bifilm content of the melts was investigated by the analysis of K-mold specimens and X-ray computed tomography (CT) of reduced pressure test (RPT) samples. It was found that liquid alloys with a higher Sr concentration had a significantly greater tendency to pore formation, which can be explained by the presence of a larger number of bifilm defects in the liquid alloy.
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Advancing Sustainable Waste Management through National Recycling Rate under SDG 12.5.1
61-72Views:567Solid waste management remains a pressing environmental challenge in both developed and developing nations. Recycling has been promoted globally as a key pathway to sustainability, yet recycling rates often provide only a partial picture of performance. In many contexts, challenges such as poorly regulated recycling policies, informal sector dominance, and practices that prioritize profit over environmental sustainability limit progress towards Sustainable Development Goal (SDG) 12.5.1, which tracks the national recycling rate. This study investigates the extent to which recycling rates reflect sustainable waste management and identifies the underlying factors that influence their effectiveness. The major objective of this study is to evaluate recycling rates as an indicator of sustainable waste management. This is further specified by: (i) examining recycling practices in selected countries (Germany, South Korea, USA, Brazil, and India), (ii) identifying key drivers and barriers that influence recycling performance, and (iii) assessing the implications of recycling rates for sustainable waste management systems. The study employed a mixed-methods approach, combining secondary data analysis, comparative country assessment, and policy review. Results show that recycling rates are useful but insufficient as a stand-alone measure of sustainability, since they are influenced by broader elements such as policy enforcement, economic incentives, public participation, and market structures. The findings highlight that Nigeria’s recycling rate remains significantly low compared to leading economies, underscoring the need for integrated waste management reforms. This research contributes to environmental management discourse by demonstrating that while recycling rates provide a benchmark for SDG 12.5.1 monitoring, they must be interpreted alongside contextual drivers to ensure meaningful progress towards sustainable waste management.
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Sustainable Energy in Aviation with Reverse FMEA Analyses
29-40Views:423This research aims to identify and evaluate the key challenges and obstacles hindering the adoption of sustainable energy in the aviation industry. The outcomes and insights derived from this research will be synthesized to provide a comprehensive overview of the opportunities and suggestions for the adoption of sustainable energy in the aviation industry. The objective of this study is to help the aviation industry’s shift toward more sustainable energy sources in order to reduce its environmental footprint and mitigate the effects of climate change.
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Potentiodynamic Study of the Effects of Nickel on The Electrodeposition of Zinc from Chloride Media
15-24Views:346Abstract. 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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Efficiency of the Machining Process of Circular Shapes by Electrical Discharge Technology
53-61Views:350Due to its high machining precision, EDM technology is nowadays very important in the production of high-precision parts for various industries. The high precision of the machined surface in combination with the ability to machine circular surfaces brings, in addition to several advantages, some negatives. The most significant negative of this machining technology is the relatively low productivity as well as the overall production efficiency. The latter is affected by many accompanying phenomena. The main accompanying phenomenon that contributes to the decline in the overall economic efficiency of EDM is the microgeometry errors that occur due to the non-homogeneity of the EDM process. Another accompanying negative phenomenon is the geometric accuracy errors of the machined surface, as a consequence of systematic destruction of the wire tool electrode, faulty interpolation in its guidance, and, last but not least, its vibration. These aspects consequently lead to the requirement for multiple applications of additional finishing cuts, which significantly reduces the overall economic efficiency of the machining process. Therefore, the experimental research aimed to search for options that can effectively help to achieve higher productivity but especially the overall economic efficiency of the machining process.
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Advancing Maintenance 4.0 through an Asset Management Framework: a South African Petrochemical Industry Case Study
1-20Views:280The rapid advancement of digital technologies has raised uncertainty about the adequacy of traditional maintenance models to meet Industry 4.0 requirements. This study develops and validates an asset management framework to support the South African petrochemical industry’s transition to Maintenance 4.0. The framework was validated through a quantitative survey conducted within a leading petrochemical company in South Africa, ensuring its practical applicability. Descriptive statistical analysis confirmed 15 of 17 framework characteristics and supported five of seven theoretical propositions. Key enablers of Maintenance 4.0 adoption include the integration of human intelligence, machine learning, and real-time data, as well as the role of organizational culture and asset resilience in shaping outcomes. The study offers both theoretical contributions and practical guidance for maintenance professionals seeking to align maintenance practices with Industry 4.0 principles, with relevance extending beyond the immediate case context.
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The Dynamic Effect of Trade Openness, Debt, and Foreign Investment in Ghana’s Economy: An ARDL Bound Testing Approach
94-112Views:510The impact of macroeconomic factors offers insight into the performance of an economy. This study investigates the dynamic short- and long-term effect of trade openness, external debt, and foreign direct investment (FDI) within Ghana's economy. Utilizing Autoregressive Distributed Lag (ARDL) bound testing and Granger causality analysis, the study examines data spanning from 1991 to 2022. The results of the ARDL cointegration test reveal a long-term relationship among the variables. However, in the short term, the findings present a mixed effect of FDI and trade openness, with both positive and negative impacts. In the long run, FDI and external debt exhibit a positive influence, whereas trade openness appears to impede economic growth. Furthermore, the Granger causality test identifies a unidirectional causality relationship between the variables and economic growth. The study suggests that the government implement investment-oriented and trade policies to stimulate economic growth.
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Investigating the Impact of Nature in Designing Cultural Environments for Children
244-256Views:383There is a tendency to communicate with nature in human beings as a set of emotional experiences. This study investigates the impact of organic architecture in creating cultural spaces for children. The concepts of nature, naturalist architecture and children educational psychology, from the perspective of scholars and researchers in this area are investigated. The children’s perception of nature and their feelings were assessed and one hundred forty respondents among the instructors of cultural centres in different regions of Tehran have answered the questionnaires. To investigate the hypotheses, Univariate T - test and F - test were applied. The results showed that the stimulation of the natural environment has a positive and meaningful effect on curiosity, participation, and fantasy in children, while they show their impressions of nature indirectly. Therefore, designing applicable spaces according to children’s physics, using appropriate colours and furniture as well as more environmentally-related spaces, can have positive effects on social participation, intuitive and verbal skills of the children.
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Adaptability of Powdered Activated Carbon Production from Ground Catering Waste Pyrolysis Coke
162-171Views:314Three mixture of catering waste was pyrolyzed at 650, 725 and 900 °C and the solid residue (coke) was examined for powdered activated carbon production. For this, the carbon content, iodine number, particle size distribution and scanning electron microscopic images were analysed. Based on the carbon content, these cokes are suitable for activated carbon production, which were 60-85 wt.% (depending on the base material and pyrolysis temperature). The studied cokes showed slightly porous structure with smooth surfaces. Because of this, the iodine number was mostly small (13-30). Based on the grinding experiments, 10 minutes of grinding was found to be optimal. After this grinding time, the reached iodine number of powdered activated carbon was 350-610.
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Ultrasonic Powder Atomization for Additive Manufacturing
69-75Views:548The 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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The Impact of labor Turnover on The Service Quality of Hotels
98-105Views:665This study aimed to know the dimensions of labor turnover (low morale, poor employees training, payment, job satisfaction) and study the effect of these dimensions on the quality of service in hotels. The results of multiple regression show that there is an effect of dimensions labor turnover on quality of service. Correlation between labor turnover and tangibility was the strongest and there is a moderate relationship between labor turnover and each of responsibility, reliability, assurance, and empathy.
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Structural Investigation of Granular Composites by Modern Methods
179-185Views:310Structural investigations of polymer-based particulate composites were carried out using modern test methods. We had composite sheets with different compositions and different injection molding speeds. In the polypropylene matrix, three types of glass beads were mixed in three weight percentages. In our investigations, the granular composites were studied with a widely used examination equipment, scanning electron microscope (SEM) and industrial computer tomography (CT) as a modern diagnostic tools. The purpose of the study was to investigate the distribution and interfacial adhesion of glass beads.
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Bekele Desta and M. Lunga: Analyzing Determinants of Construction Project Resilience and Success in Ethiopia: a Structural Equation Modelling Approach (PLS-SEM). International Journal of Engineering and Management Sciences. doi: 10.21791/IJEMS.2026.03
124-125Views:126In the original publication, the authors identified three errors.
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The Effect of Fluxes on the Melt Quality of AlSi7MgCu Alloy
372-380Views:399The presence of inclusions such as oxides, carbides or refractory particles can be harmful to the mechanical and surface characteristics of castings. Inclusion-rich metals result in lower fluidity and feeding capability during casting. Nowadays, solid fluxes are widely used in foundries in order to reduce the inclusion content of aluminium melts. In this study, the effect of four different fluxes on the melt quality was studied. First, the inclusion content of the flux-treated melt, and then the properties of the fluxes (i.e. chemical composition and melting temperature) were examined.
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Surface Quality of Carbide Metal After Electrical Discharge Machining
31-38Views:330Recently, the requirements for machining shape-complex products made of hard-to-machine materials, including carbide, have been increasing significantly. However, their machining is rather problematic. Additionally, a high-quality standard of the machined surface is generally required, not only in terms of roughness but also in terms of the geometric accuracy of the machined surface. All this while maintaining a high level of economy in the machining process. However, meeting these demanding requirements in real technical practice is not always an easy task. Moreover, in combination with modern machining processes, only a limited number of production technologies can meet this requirement. Therefore, due to the high demands placed on today's modern production and the required high standard of the machined surface, progressive EDM technology is increasingly finding its application. And it is through this progressive technology that it is possible to achieve relatively good success in carbide machining. The aim of this paper was therefore to describe in detail the results of an experimental investigation aimed at identifying the quality of the machined surface achieved in terms of the roughness parameters of the machined surface in the electrical discharge machining of selected types of carbides using a wire tool electrode.
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The Mechanical Properties of 3D Printed CuZn28 Brass Specimens with Different Orientations
253-259Views:442In this paper, the properties of CuZn28 brass raw material were presented. The 3D printed metal specimens are made from this material with different orientations. Their mechanical properties (tensile strength, yield strength) and elongation were investigated according to MSZ EN 6892-1: 2012 standard. The strength of the different printing directions is analyzed and it is determined which printing direction is the most favourable. Finally, the effect of the different printing directions upon the structure of the material is studied.
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Creativity and Innovation to Improve Processes in a Textile Industry
80-96Views:379In this scientific work, the My Creative Idea (MIC) program was created and developed in the Coteminas S.A. textile industry, distributed among the organization's units in the country with emphasis on the São Gonçalo do Amarante unit in the state of Rio Grande do Norte. The aim was to critically analyze the improvements of industrial-scale processes resulting from the creativity and innovation intrinsically incorporated and experienced daily in the program. Thus, the general objective of the work was to evaluate the improvements in the productive processes coming from an innovation program in a textile industry, considering as specific propositions with respect to calculating the gains with reduction of losses, cost of implementation of ideas and measure financial returns and evaluate employee satisfaction according to the program. Moreover, there was free access in the company to be able to collect valuable information that could formalize a robust database for later structuring of the document, as well as the application of action research in the form of questionnaires. Therefore, the results verified clarified and emphasized the program's aggregating character to the organization in a general way under aspects that approach the financial spheres, the quality, and the satisfaction and motivation of the employees involved in this whole scenario. I suggest continuing to work on a continuous improvement methodology to further enhance My Creative Idea over the years, as well as insert this method of work to units that have not incorporated this program into their business strategies.
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The Role of Quality 4.0 in Business Process Management: a Bibliometric Study
37-56Views:309Quality 4.0 builds on the principles of Industry 4.0 to improve quality management. Integrating Quality 4.0 into Business Process Management (BPM) examines how digital technologies enhance process efficiency and innovation. The main research question is how Quality 4.0 can be aligned with existing BPM frameworks and how the digital transformation of traditional quality management techniques facilitates efficiency. A bibliometric analysis was conducted using the Scopus database, employing keyword analysis, link mining techniques, and network mapping to identify research trends and gaps. The results show the main directions of research on integrating Quality 4.0 and BPM and highlight implementation barriers such as organizational resistance and the need for strategic alignment. The study also suggests directions for future investigation, including the development of standardized frameworks for evaluating digital BPM outcomes and exploring emerging debates around human-centric, sustainable, and resilient approaches reflected in Industry 5.0 and Quality 5.0.
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Trends in Greenhouse Gas Emissions and Renewable Energy Policies in the EU and USA, with Special Emphasis on the Transportation Sector
219-231Views:428The aim of this work is to review recent trends in the field of greenhouse gas (GHG) emissions and renewable energy policies of the European Union and the United States of America. During the last few decades, there was a significant shift within the political attitude towards these fields, therefore important changes were realized in the electricity production and the climate policy. In the present paper, we discuss the current situation focusing on the transportation segment.
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Bekele Desta and M. Lunga: Segmenting the Impact of Organizational Structure and Leadership on Project Resilient and Project Success in the Ethiopian Construction Industry: a FIMIX-PLS & PLS-POS Approach. International Journal of Engineering and Management Sciences. vol. 10, no. 3, pp. 73–103, doi: 10.21791/IJEMS.2025.17.
122-123Views:134In the original publication, the authors identified four errors.
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Mixing Power Requirement Determination in Agitated Drum Using Dimensional Analysis
76-88Views:504The mixing of granular materials in an agitated drum can be characterized by the dimensionless power equation. The equation was created by dimensional analysis, for which the parameters affecting the mixing power requirement were collected based on the literature. The most important of these are the rotational speed, the drum loading factor, the geometric and physical properties of the mixing drum and the granular materials. The dimensionless power equation is used to estimate with reasonable accuracy the Power number within the given range of applicability , which has been validated by measurements. From the Power number, the mixing power requirement of the mixed granular material can be calculated, which can be used as operational data for selecting the mixing motor.
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Operational Feasibility Assessment of Geothermal Heat Harnessing Systems
46-53Views:379Renewable energy sources are now essential to establish sustainable development. This paper examines one kind of source the geothermal energy. For geothermal energy when combined with a heat pump COP can be used for evaluation. For solely geothermal sources different approach is needed thus in the paper, a new geothermal heat production coefficient is used to examine the operational feasibility. For the assessment, many hypothetical buildings were created to model their heat demands. Two types of calculation methods are used for heat demand calculation. Based on the results, the maximum depth of a geothermal borehole and economically critical qualitative coefficient was concluded.
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Changes in the Financial Condition of Families in Hungary between 2000 and 2019
712-722Views:503The financial condition of families living on wages is function of many factors. It is determined, among other things, by the development of wages, social benefits, tax rates and the amount of allowances that can be granted. The part of the tax system that affects the largest segment of individuals changes every year, and even during the year, reducing predictability. In recent years, discussions over the taxes have shown that the rate of personal income tax cannot be evaluated separately from the social security contribution rate. Gross average earnings - on the grounds of raising the minimum wage and the guaranteed minimum wage - have more than four-times in nearly 20 years. However the rate of growth is higher in the average net earnings due to changes in the tax system. Compulsory determined wages increased to almost six-times over the years under investigated. But in 20 years, how much has the income situation of an average family living on a salary become more favourable or more unfavourable? In our study we are looking for an answer to how the increase in the minimum wage and the changes in the law how to have affected the livelihood.
