The Six Sigma DMAIC can be considered a guide for problem solving and product or process improvement. The majority of companies start to implement Six Sigma using the DMAIC methodology. The paper deals with application of Six Sigma using the DMAIC methodology in the process of product quality control. The case study is oriented on the field of metallurgical operations. The goal of the Six Sigma project was to ensure the required metallurgic product quality and to avoid an increase in internal costs associated with poor product quality. In this case study, a variety of tools and techniques like flow chart, histogram, Pareto diagram, analysis of FMEA (Failure Mode and Effect Analysis) data, cause and effect diagram, logical analysis was used. The Sigma level has improved by approximately 13%. The achieved improvements have helped to reduce the quantity of defective products and the processing costs (technology for re-adjusting). Benefits resulting from the DMAIC implementation can be divided into three levels: the qualitative, economic and safety level.

The main task of safety and health at work is to protect the most important thing we have, the health of each of us. Employers are able to anticipate and prevent risks by properly implemented occupational safety and health management systems. The basic task of the article is to describe the history of safety management systems to identify the state of implementation of the ISO 45001 system in the world. Subsequently, the article describes the ISO 45001 standard from the perspective of the PDCA cycle and describes the benefits and importance of implementing the ISO 45001 standard. The conclusion of the article deals with the development trend of the occupational health and safety management system according to STN ISO 45001:2019 in the context of occupational accidents in the conditions of the Slovak Republic.

The literature regarding the Reverse Indentation Size Effect (RISE) is scarce, the occurrence of which is assumed for plastic materials, including metals. The content of this article is to study the relationship between applied load and measured values of the Vickers micro-hardness of 19 metals with different types of lattices, measured with a Hanemann tester. The values of the load ranged between 0.09807 N (10 g) and 0.9807 N (100 g). The size and character of the Indentation Size Effect (ISE) were evaluated by Meyer’s power law (index n), Proportional Specimen Resistance (PSR), and Hays—Kendall methods. Meyer’s index n ranged between 1.65 for Mo and 2.44 for Ni. A correlation was found between the micro-hardness and Meyer’s index for metals with FCC and HCP lattices. The measured value of Vickers micro-hardness is influenced by the size and nature of the ISE. If this is not taken into account, it may be misleading. For this reason, we recommend using the “true hardness”, determined by the presented method.

The main mission of the internal quality system in educational institutions is to develop the importance of quality in all processes, create suitable conditions for increasing the loyalty and professional development of faculty staff, continually improve student satisfaction, and achieve recognition of educational institutions in the eyes of the public. In the Introduction, this paper covers the current state of the field of quality assurance of higher education in Slovakia. Quality management models that can be used appropriately and effectively in university conditions are identified in the next section. The aim of this overview section was to summarize the advantages and disadvantages resulting from the implementation of quality management models. The paper also includes a case study in which selected models of quality management implemented at a private university in Slovakia are described, especially the process model ISO 9001 and the common assessment framework (CAF) model. The self-assessment within the CAF model was carried out by a questionnaire survey; the obtained data were assessed by classical CAF scoring. The aim of the self-assessment was to identify problem areas and opportunities for improvement and to propose corrective actions. The specifics of the implementation of quality management models at a private university and the benefits resulting from the application are also been defined at the end of the article.

The digital twin (DT) is undergoing an increase in interest from both an academic and industrial perspective. Although many authors proposed and described various frameworks for DT implementation in the manufacturing industry context, there is an absence of real-life implementation studies reported in the available literature. The main aim of this paper is to demonstrate feasibility of the DT implementation under real conditions of a production plant that is specializing in manufacturing of the aluminum components for the automotive industry. The implementation framework of the DT for engine block manufacturing processes consists of three layers: physical layer, virtual layer and information-processing layer. A simulation model was created using the Tecnomatix Plant Simulation (TPS) software. In order to obtain real-time status data of the production line, programmable logic control (PLC) sensors were used for raw data acquisition. To increase production line productivity, the algorithm for bottlenecks detection was developed and implemented into the DT. Despite the fact that the implementation process is still under development and only partial results are presented in this paper, the DT seems to be a prospective real-time optimization tool for the industrial partner.

European Union legislation requires organizations to assess their processes in the context of risk management. The main task of risk management is to manage all risks that can significantly affect the outcome of processes. The article is focused on risk evaluation in pressure leaching at elevated temperature using the method Fault Tree Analysis (FTA). The effectivity of pyrite and arsenic pyrite decomposition by oxidative pressure leaching is influenced by the duration of the process, by the temperature, concentration of the leaching solution and by a density of the slurry. It was found that, under equitable conditions, the arsenic pyrite decomposes more intensely than pyrite. Under laboratory conditions, leaching is performed in an autoclave. Due to the aggressive environment, increased pressure and temperature, process failure is possible. Its probability was calculated by FTA. It has been found that the probability of the top event in the examined process was disproportionately high (0.057) and represents an invitation to take corrective actions. The Monte Carlo method was used for the simulation of the effect the probability of basic events on the probability of the top event—the failure of the leaching process.