Agnieszka Kujawińska

Ergonomics as Significant Factor of Sustainable Production

Europe 2020 is development strategy set by European Union for next decade. According to Jose Manuel Barroso (2014) in EU continuously changing intelligent and sustainable economy growth is needed as it is favorable not only to put attention and protection about natural environment and ecosystem but also to bigger proactive social commitment. Parallel work on these priorities should help EU organization as also member countries in economy prosperity grow in global perspective through increase of employment, productivity, social cohesion. Moreover it should be achieved also by negative influence on environment downscaling (especially in waste management) and bigger employers responsibility awareness of working conditions.

Statistical Approach to Making Decisions in Manufacturing Process of Floorboard

The study was conducted at a Polish company operating in the wood industry under the R&D project “Increasing the effectiveness of use of wood in manufacturing processes”, aimed at reducing raw material waste in the surface layer manufacturing process. Results of our studies on the improvement of the wet cutting technology are presented in this paper. Minimization of variability is the first step to reduce material consumption in the process of cutting wood into lamellas. Appropriate values of factors which significantly affect lamella thickness after the cutting operation can be determined through real-life experiments. The methodology is to improve and/or reduce operational allowances and to redesign the tolerance and machine parameters/setting.

Measurement System Analysis Combined with Shewhart’s Approach

The paper presents new procedure of methodology for statistical assessment of measurement systems variation (methodology known in the literature as Measurement Systems Analysis, MSA). This procedure allows for calculation and monitoring in real time (that is on-line) of measurement system (MS) characteristics which determine its usability for manufacturing process control. The presented solution pointed out the gap in process control, which consists in lack of methods for monitoring measurement processes in the on-line way. Their key point consists of taking samples that are also needed for the process control chart for the needs of the MSA method. This means that the samples are taken directly from the production line and during the production process. The method is combined with the standard procedure of statistical process control (SPC) with the use of process control charts. It is based on two control charts. The first one is called AD-chart (Average Difference chart) and it allows to estimate the variation between the operators and stability of the monitored measurement system. The second control chart illustrates the %R&R index (Repeatability and Reproducibility) and allows to monitor the MS capability.The paper also presents authors’ proposal of guidelines about the reference value for the %R&R index calculation and assessment. Recommendations and guidelines for choosing the reference value are based on two criteria: information about sample and manufacturing process variation and the purpose of using MS (product or process control).

The Role of Human Motivation in Quality Inspection of Production Processes

Despite fast technological progress, machine-oriented production solutions and more demanding customer needs still human presence in production is evident, important and needed. In quality inspection human uses own senses when deciding about products quality. Decisive step is then the most complex part of inspection with regard to big number of product attributes, variable attributes and often limited possibility to measure product characteristics. Attribute inspection is much more difficult than control based on measurements and figures. Effectiveness of attribute inspection is always lower than based on measurements due to risk of human mistake during inspection. It can appear two types of failures during inspection: defects overlooking, improper classification. Human is unreliable part of inspection. One of key factors influencing on inspection performance is motivation. Motivation types differs people. With regard to that fact it is stated that human motives investigation needs to be carried out already on personnel selection phase.

Soft Modelling-Based Methodology of Raw Material Waste Estimation

The paper looks at soft modelling-based estimation of raw material waste for various variants of a technological process under development. A methodology of assessment of new technology variants, in terms of minimization of the input material waste, is presented. Results of an analysis of variants of a new technology of manufacturing of the middle layer of a flooring board, carried out according to the developed methodology, are shown. The assessment is performed in an original software tool for waste simulation. It is shown that the developed methodology supports the estimation of material waste and assists in the selection of the optimal variant of the process, taking into consideration the constraints of the organization.

Organization of Visual Inspection and Its Impact on the Effectiveness of Inspection

The research presented in this paper was aimed to analyse and evaluate the impact of organizational factors on the effectiveness of visual inspection in the manufacturing of electronic systems for the automotive industry. The study was carried out according to the authors’ own methodology consisting of three stages: detailed description of the process, developing a study plan and analysis of the results. The experiment was conducted and influence of three factors: type of inspection, shift and type of defect, was taken into consideration and evaluated. Recommendations were made to improve the quality of such inspections that will lead to the improvement in the final quality of the product.

Methodology Supporting the Planning of Machining Allowances in the Wood Industry

The paper presents a methodology of determination of technological allowances in the manufacturing process of semi-products of deciduous timber (oak). Soft modelling has been proposed for the determination of allowances for the variability of consecutive technological processes caused by the material, machine, operator, measurement system and random factors. The proposed methodology has been applied in the technological process of manufacturing the surface layer of a floor board (lamella). The method of identification of a soft model for the process of cutting timber into lamellas has been presented. Twenty soft models have been identified and recommendations have been made, based on experiments, for reducing the variability and centering the process. The proposed process modelling method facilitates economic estimation of allowances, controlling the manufacturing process and forecasting its future condition. As a result of the research, the manufacturing capacity of lamellas of acceptable quality has been increased by ca. 30%.

Artificial Neural Networks as a Means for Making Process Control Charts User Friendly

The paper discusses usability of various pattern recognition methods, especially based on artificial neural networks for decision making support in process control chart analysis. Their effectiveness for detecting process instability is compared with the effectiveness of a human operator and of a widely accessed commercial statistical software. The results are verified on the basis of data obtained from real production processes.

Application of Cluster Analysis in Making Decision About Purchase of Additional Materials for Welding Process

The concept of Industry 4.0 requires a computerized manufacturing environment which permits to increase flexibility of processes, faster communication and integration of various areas of business operation. It also involves collecting and processing a lot of information in databases. In order for an enterprise to develop, it must be able to transform this data into useful knowledge. Extraction of knowledge from datasets is made possible by Data Mining methods. The paper presents an analysis of the use of Data Mining methods in support of purchases of manufacturing materials. The practical problem of selection of fluxing agents for Submerged Arc Welding (SAW) is solved by applying cluster analysis. The authors present the results of an analysis for 213 combinations of flux-welding wire, conducted by the hierarchical (Ward method) and non-hierarchical (generalized k-means method) cluster methods. The approach proves to be suitable for aiding the decision making process.

Improvement of Acceptance Sampling Inspection for the Operation of Sealing Packages

One of the many purposes for which data are gathered from manufacturing processes is assessment of these processes against predefined criteria. Assessment results are often used for monitoring and supervising the process based on a developed statistical model. This paper looks at the issue of selection of sample size for sampling inspection in the process of packaging medical products. Packaging is an important stage of manufacturing medical products, since the package ensures safety and sterility of the product. In the process of packaging medical products, the operation of sealing the package is of key importance in terms of following medical procedures. Tensile strength of the seal is the critical feature. This paper presents a case study in which an efficient statistical sampling plan was executed for the process of sealing medical packages which led to the saving of time as well as cost.