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Six Sigma as a method of improving the quality of service process

Abstract

The objective of the analysis conducted and described in this paper has been to present the practical application of the Six Sigma method based on the DMAIC cycle in improving the quality of the service process. The first part of the article contains the theoretical framework of six sigma and the issue of using its tools in the aspect of services. Afterwards, there has been calculated the initial sigma value which indicated the need for improvement. Measurement phase has been developed by the value stream mapping, process FMEA and customer survey which results have been analyzed in Pareto chart and fishbone diagram. Improve phase includes the Impact&Effort Matrix and target sigma level that can be achieved as a result of failures reducing and service quality improvement.

Open access
Social engineering of human resources and provision of medical services on leadership styles in hospitals

Abstract

Paper present impact of human resources issues as well as issues related to provision of medical services on leadership styles in hospitals in Poland. In this study a descriptive research design was used and a quantitative research was conducted, which was based on the so-called BOST methodology. Surveys were conducted among department heads of 10 public hospitals of various referral systems from the Upper-Silesian Agglomeration providing various types of medical services (which shows a large variety of research sample) operating in Poland. The research showed that both improtance of service provision as well as human resources were not as important as they should be.

Open access
Surface Hardening Vs. Surface Embrittlement in Carburizing of Porous Steels

Abstract

Carburizing increases the contact fatigue resistance of sintered steels, but the surface hardening may result the formation of surface brittle cracks due to the combined effect of high hardness and porosity. The effect of carburizing on the embrittlement of the case of a 7.3 g/cm3 1.5%Mo - 0.25%C sintered steel was studied. The phenomenon was analyzed theoretically and verified by experiments. The resistance of the carburized steel to surface brittle cracking increases with the load bearing surface and the decrease of the maximum pore size, of the surface microhardness and the friction coefficient. The theoretical analysis was implemented in a design procedure for parts subject to contact stresses.

Open access
Hierarchic Optimization of Resource the Resources Allocation among the Units of Aviation Company

Abstract

This paper deals with the problem of optimal resource distribution in optimal way among the units of an aviation company. This task could be solved by using the method of dynamic programming. Using Mathcad 14 programming language, there was created a special program that allows to make corresponding calculations. The solution of the real task for an aviation company is observed in this paper as a numerical sample of limited resource distribution between the units of the company in order to get the maximum profit.

Open access
Airline Quality Assessment Methodology Taking Into Account the Flight Safety Level Based on Factor Analysis

Abstract

In this article, the authors offer a methodology for determining the quality of airline performance by taking into account the level of flight safety on the basis of factor analysis and the results of methodology approbation in the conditions of a functioning airline. The assessment of the level of airline performance quality taking into account the level of flight safety within a certain time span is rather sensitive, informative and reliable. They allow us to detect those changes in industrial and economic conditions and factors that are related to a certain degree of potential deterioration of flight safety. This creates conditions for revealing the tendencies towards the deterioration of flight safety at the stage of their origin, when they have not yet caused deep, irreversible changes in the flight safety of an airline.

Open access
Amorphous materials in the production of new implants

Abstract

Amorphous materials based on magnesium are new materials for potential biomedical application, especially for new implants, as they bear resemblance to titanium implants. Mg66Zn30Ca4 alloy has specific properties, especially mechanical and corrosive, therefore, it has biomedical application as its properties are better than that of other materials. The following paper describes amorphous alloy based on magnesium, properties and shows how to produce amorphous samples of Mg66Zn30Ca4.

Open access
The application of the FMEA method in the selected production process of a company

Abstract

The aim of this article is to show the use of the analysis of the failure causes and effects as a prevention tool in controlling the quality of a given production process in the company. The scope of the work covers an analysis of a selected process, definition of inconsistencies present in this process, and then the FMEA analysis. In the production company one should implement thinking and actions based on the so-called ‘quality loop’ – it is an interdependence model of the undertaken actions which affect the quality shaping. It is carried out from the possibility for identifying a customer’s requirements through a project, production process, up to the assessment of effective capability for meeting the defined requirements.

The application of such an approach enables to take the actions improving the operation of quality management in a systemic way.

Open access
Changes in hardness of magnesium alloys due to precipitation hardening

Abstract

This paper deals with the evaluation of changes in hardness of magnesium alloys during precipitation hardening that are nowadays widely used in different fields of industry. It focuses exactly on AZ31, AZ61 and AZ91 alloys. Observing material hardness changes serves as an effective tool for determining precipitation hardening parameters, such as temperature and time. Brinell hardness measurement was chosen based on experimental needs. There was also necessary to make chemical composition analysis and to observe the microstructures of tested materials. The obtained results are presented and discussed in this paper.

Open access
Influence of load and reinforcement content on selected tribological properties of Al/SiC/Gr hybrid composites

Abstract

Hybrid materials with the metal matrix are important engineering materials due to their outstanding mechanical and tribological properties. Here are presented selected tribological properties of the hybrid composites with the matrix made of aluminum alloy and reinforced by the silicon carbide and graphite particles. The tribological characteristics of such materials are superior to characteristics of the matrix – the aluminum alloy, as well as to characteristics of the classical metal-matrix composites with a single reinforcing material. Those characteristics depend on the volume fractions of the reinforcing components, sizes of the reinforcing particles, as well as on the fabrication process of the hybrid composites. The considered tribological characteristics are the friction coefficient and the wear rate as functions of the load levels and the volume fractions of the graphite and the SiC particles. The wear rate increases with increase of the load and the Gr particles content and with reduction of the SiC particles content. The friction coefficient increases with the load, as well as with the SiC particles content increase.

Open access