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Abstract

The publication describes two ways of shopping, taking into account the CPI (Consumer Price Index) inflation rate. In the first case, changes in the sales price are made in a continuous manner in accordance with the inflation rate, and therefore it is better to make larger purchases. In the second case, it is better to carry out smaller purchases, because it is characterized by one-time adjustment of sales prices to the entire purchased a lot of goods. Both cases were verified based on the Solver tool, using non-linear, integer-based optimization. The final result was to determine the optimal purchase quantities with the minimum inventory costs.

Abstract

The basis for the functioning of every organization and achieving the set goals are employees. It is they who shape the image, create the organizational culture and reputation of the company in the environment. Their competences, knowledge and skills determine the efficiency and effectiveness of the organization’s operations. Thanks to their work, products and services are created that meet social needs and thus organizational progress. The aim of this work was to conduct research on the organization’s ability to identify and retain the best employees, the ability to promote desired attitudes and behaviors, as well as to create a friendly and rewarding work environment that are key factors for business success. Updating the knowledge possessed by employees and developing new skills is often crucial in keeping the organization on the market.

Abstract

The lack of a common methodology on compaction theory stimulates developers of road construction equipment to create various approximate methods for their calculation, the number of which, at the present time, is comparable with the nomenclature of the proposed designs of rollers. The article presents the analysis of the deformable shell behavior of a road roller, and the compacted material under its compacting roller, in a situation when a rigid circular shell of the roller is replaced by a forcefully deformable elliptical shape, which, unlike the circular design, allows variation, adjustment and optimization of the road roller impact on the material to be compacted.

Abstract

The production of two-wheeled rolling stock represents, at first glance, a simple assembly process that significantly affects the overall functionality and safety of the vehicle. This is due to residual stresses that arise after assembly by pressing the wheel on the axle. The state of stress after assembly remains in the design has a decisive influence on the load-bearing capacity of the two-wheel drive, its lifespan but also the transfer of the pulling force in the case of locomotives. Therefore, it is very important to find suitable methods for determining residual stresses. Numerical and experimental approaches are already in place to gain information on the state of stress after compression, or during a real operation. The developed techniques and tools for estimation of residual stresses in locomotive wheel treads based on the acoustoelasticity effect using electromagnetic acoustic transformation are described in the paper. The original results of residual stress measurement in the treads during a technological cycle of locomotive wheel pair manufacturing are presented.

Abstract

The aim of the present paper is to study the Galvanic Skin Response (GSR) level on subjects affected by stress. The device that we have used, connects to the people by finger electrodes to record GSR. The purpose was to find statistical differences between the activities (mental task, walking, sitting and to fill out a survey about their lives) and their stress level. During the experiment, it was found that the survey caused the source of high stress and increasing skin conductance was caused by sweat secretion (mental, physical activity). Is needed to work of collecting data from more subjects because GSR is depended on human behaviour, is variable upon many factors (their eating habits, their emotional state, their gender, their relationship with family, etc) and we need to build a substantial data set for a valid research.

Abstract

Methods of education applied at universities have a direct impact on matching of knowledge, skills, but also on the approach to the professional sphere of graduates, in relation to the needs and requirements of employers. It is particularly important in the case of Occupational Safety and Health field of study. Using the available means of technical and informational support of education, one should concentrate on shaping individual thinking. In times of rapid technological development, it is not the duplication that counts, but the creative thinking that must be accompanied by the ability to work in a group. And in this direction, according to the author, academic education should pursue. In the publication, the author analyses the applied methods of education. For this purpose, the results of the study of the participant’s observation, direct interviews with employees and employers, as well as the results of a survey conducted among students of the Czestochowa University of Technology, will be used. The analysis will be carried out in terms of the evaluation of applied methods of education - quality, usefulness, adjustment to expectations (students and employers), attractiveness of form and content.

Abstract

In according with the stated conception the purpose of the present work is the reconstruction of some of innumerable microstates of α phase of ferritic steels, definition of its macroparameters and their subsequent comparison with indicators of mechanical properties of industrially let out steels. The establishment of a correlation between the measured indicators of mechanical properties of already created materials and the calculated state parameters of their basic phase opens an opportunity of mechanical properties prediction of materials in dependence on their prehistory that as a matter of fact represents the central task of material science. Simulation of α-phase state of series of industrially let out ferritic steels and alloys is executed in the assumption of identity of its composition to composition of steel or alloy as a whole. The correlation between indicators of mechanical properties of steels and alloys and state parameters of their basic phase is traced.

Abstract

Problems related to work safety have been accompanying humanity since the dawn of time. In times before the Industrial Revolution, human and animal muscle strength was used to work, and “safe work” solutions were developed and introduced individually by the user or supervising the work. Only a change in the way work was done due to the industrial revolution, the introduction of new energy sources, the transformation of manufactories into factories and the birth of the working class brought about greater, concrete changes. It was at that time that various machines and devices began to be introduced into the workplace, which on the one hand improved work and on the other hand created more and more potentially dangerous situations. Security was started holistically and institutionally. With the transformation and return of capitalism, the subject of real work safety returned. Health and safety was to be not only a fashionable slogan, but a value that was supposed to guarantee profit – in accordance with the principle that accidents reduce productivity. It was also connected with the process of adapting Polish law in the field of health and safety to the law of the European Union (EU), which resulted from Poland’s pursuit of EU membership. Moreover, an important factor initiating these changes was the interest of enterprises in quality management systems compliant with the ISO 9000 series and environmental management systems compliant with the ISO 14000 series, and related attempts to adapt the system management concept to the area of occupational health and safety, resulting in PN-N standards 18000 series. This publication analyzes the new standard PN-ISO 45001:2018 – “Occupational health and safety management systems – Requirements with guidance for use” comparing it with the standard PN-N 18001:2004 – “Occupational health and safety management. Requirements”.

Abstract

Ischemic heart disease is the most common heart pathology in medical practice. Proper assessment of the size of myocardium injury and its consequences on the heart function is extremely important both for a correct drug therapy and for interventional approach. Most frequently the left ventricle is affected. The need for accurate evaluation of the impact of left ventricular myocardial damage has led to the development of new imaging techniques and improvement of the existing ones. At the moment the most commonly used imaging method for the assessment of left ventricular function is echocardiography. Cardiac Magnetic Resonance and nuclear tomography are precious imaging techniques as well. They are more expensive but bring valuable information when used in adequate situations.

Abstract

Incremental forming process is a relatively new process among researchers, which is yet to be implemented in automotive and aerospace industries. The researchers are studying various process strategies and methods to improve the geometrical accuracy of the parts obtained by incremental forming, because the geometry of the parts is one of the key factors holding back the process industrialization. One good method to investigate the benefits of a process strategy is by means of numerical analysis, from which the results obtained can confirm or disprove the gains of the researched strategy. The aim of this paper is to present the advantages of using a fluid under pressure as a supporting die instead of using a conventional fixed backing plate for the single point incremental forming process.