Decision Making in Manufacturing and Services

Assessment of the impact of 3D printed water-lubricated cutless bearings material on vibration parameters

Jędrzej Blaut — 2022-12-31

The tested bearings were subjected to equal loads and rotational speeds, using water as the lubricant. Analysis showed that they achieved the best vibration damping at lower speeds, between 600 and 1100 rpm. Comparative studies of bearings made of different materials, such as available on the market bearings made of rubber, bearings printed with a 3D printer from PETG, PLA, ABS or Tribo filament materials, revealed differences in their vibration damping ability and operational stability. Conclusions from the study suggest that higher vibration acceleration may increase the radius of the trajectory, which may affect the function and performance of the bearings. The importance of the operational stability of water-lubricated plain bearings cannot be assessed solely on the basis of the RMS of vibration acceleration or trajectory radius. Both of these parameters are crucial from the user's point of view, especially in the context of various applications such as electric boats.

Identification of key factors for the successful development of agricultural biogas plants in Poland

Grzegorz Ginda — 2022-12-31

In Poland, the potential for biogas production is high. important source of renewable energy and contributes to reducing the emissions of methane, a greenhouse gas. In this article, based on materials from the National Agricultural Advisory Centre (KOWR), literature, and statistical data, the implementation of the agrigas plant construction programme was evaluated in individual voivodeships. Based on the collected data, it was concluded that the most meaningful factors for the successful development of Polish agricultural biogas plants are biogas production technology, substrate availability, energy price from renewable energy sources, waste disposal costs, population density in the commune, and allocation of places in local spatial development plans (MPZP). DEMATEL technique was used to identify key development factors. The results of the study provide useful information for both government and local authorities in the search for effective ways to drive the sector's development.

Risk management in the heating industry

Natalia Iwaszczuk — 2022-12-31

The heating industry plays a very important role in countries with a cold and temperate climate. Together with the power industry, it determines the energy security of these countries. That is why it is so important to study the risks that threaten the stability of heating companies. The article identifies risks divided into three groups – general economic, industry and specific risks. A risk map was drawn up and a qualitative analysis of their impact for the aforementioned companies was carried out. Such a map is a helpful tool in making decisions related to risk management and ensuring the stability of the functioning of business entities.ul information for both government and local authorities in the search for effective ways to drive the sector’s development.

Heuristic algorithm for lot sizing and scheduling on identical parallel machines

Roger Książek — 2022-12-31

In this paper a newly developed heuristic algorithm for lotsizing and scheduling on identical parallel machines is presented. A basic concept and an aim of lotsizing and scheduling are described and clarified. Furthermore, models for considered problems for fixed and variable demand as well as for one and many identical parallel machines are presented. A concept and a formal description of newly developed heuristic algorithm is described. The paper includes in details the obtained results and solutions of conducted experiments and the description of used data sets.

Decision support for allocating farmed fish to customer orders using a bi-objective optimization model

Sunniva Haukvik Knudseth — 2022-12-31

Aquaculture is an important industry in certain coastal areas. Focusing on farming of salmon and trout, an operational planning problem arises with the goal of allocating supply of fish to demand expressed through customer orders. This paper provides a conceptual model of such a planning problem, defines a corresponding bi-objective mathematical programming model. The problem is novel with respect to the structure of the transportation of fish, and the rules for satisfying customer orders with respect to fish size, quality, certification, and health status. Computational experiments are conducted to gain further insights into the use of the provided model to provide support for planners involved in the operational decision making. Results indicate that the bi-objective optimization model can be useful in situations where supply is insufficient to cover all the demand within a given planning horizon.