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Abstract

Designing and proper implementation of effective processes and providing the customer with high quality products undoubtedly determines the stable position on the market. The aim of the study was to analyse the cost and value of the technological process of doors in the context of creating added value and to identify unnecessary processes (not creating added value) in relation to which appropriate corrective actions could contribute to their elimination. Thanks to the application of remedial measures, consistent with the lean manufacturing concept, the study eliminated, among other things, operations related to unnecessary transport and storage of products, which resulted in both the reduction of time and costs of process implementation.

Abstract

The paper presents research on the near real-time atmospheric sounding system. The main objective of the research was the development and testing of the weather sounding system based on a weather balloon. The system contains a redundant system of radiosondes, a lifting platform containing weather balloon and a holding system as well as ground station. Several tests of the system were performed in August and September 2019. Altitude, reliability, resistance to weather conditions and data convergence were tested. During tests, new procedures for such missions were developed. The final test was performed for the ILR-33 Amber Rocket as a part of pre-launch procedures. The test was successful and allowed to use acquired atmospheric data for further processing. Several post-tests conclusions were drawn. The altitude of sounding by a weather balloon depends mostly on weather conditions, the amount of gas pumped and the weight of a payload. The launching place and experience of the crew play an important role in the final success of the mission, as well.

Abstract

Making a complex analysis of the problem in order to identify the root of its occurrence, is the process burdened with the risk of uncertainty. This risk is in case of the quality analysis, in which the choice and making a decision is not confirmed by reliable information (number). This risk is in case of the quality analysis, in which the choice and making a decision is not confirmed by reliable information (number). But these techniques do not include the risk of uncertainty, so their sequence should be expanded about the appropriate method, to take this into account. It was considered beneficial to demonstrate that this method is the Fuzzy Analytic Hierarchy Process method (FAHP). The aim of the study to implement the FAHP method in the sequence of traditional quality management techniques (Ishikawa diagram and 5Why method) and proposition new, not practiced yet the method to complex analysis of the problem and identify the root of its root cause. The subject of the study was the furniture front, on which the incompatibility was identified (shortened foil). From the categories to which the potential causes of the inadequate foil were assigned, by using the Ishikawa diagram and the FAHP method in an integrated manner, were defined the most important categories (method and machine) in a precise (numerical) way. Next, using the same tools, the relationship between the potential causes was analysed and selected the main causes of the problem. Then, by using the 5Why method the root of the problem was defined (lack of the new machine and failure to comply with labor standards). The obtained results could differ depending on the subjectivity, however, the method itself proved to be effective and can be used to solve other types of the problem.

Abstract

The use of cast aluminium has still increased, so have the mechanical property requirements. By casting and also in other metallurgical processes, the inclusions enter to the molten aluminium alloy and it exhibits poor ductility or toughness. It can cause a variety of problems in the manufacture of aluminium alloy castings. Therefore, the purification of the molten aluminium alloy is one of the most important processes for improving the quality of Al-products. Filters have been used for many years in order to improve the quality of castings. The inclusions in molten secondary AlSi7Mg0.3 cast were removed using depth filtration by ceramic foam filters of 20 ppi porosity. Were used 4 types of ceramic filters in 2 thicknesses (15 and 22 mm); Brinell hardness and porosity were measured. Quality of microstructure (occurrence of oxidic particles and larger non-metallic inclusions) was observed. Experimental results show that the insertion of ceramic filters into the inlet system has contributed primarily to a decrease in porosity. On the microstructure, the inclusion of filters was not significantly reflected.

Abstract

Presented paper concentrate on problems connected with the function of operation management within the company. Operation function is responsible for producing products and delivering services. But it needs support and input from others areas of the organization. The aim of the paper it to analyze on the basis on inter-national the main functions of operation management. We can distinguish seven main functions of operation management in the industrial enterprise: planning, scheduling, purchasing, controlling, quality control and inventory control. In each of those fields operations managers should conduct many decision affecting of-organization effectiveness.

Abstract

The presented paper considers a comparison of the traditional methods for the state maximal probability determination to the proposed hybrid probabilistic and variational concept. It is shown the advantages of the described multi-optional hybrid-effectiveness functions uncertainty measure conditional optimization doctrine in the sense of avoiding the traditional ways analytical complicatedness concerning the maximal probability of the possible state determination. The results of the numerical example are presented.

Abstract

The developing countries of Asia, are faced with rapid changes as far as the economic, political, socio-cultural factors are concerned. These changes require greater investment in basic and higher education, as well as development of skills, in order to support the transition to a high-tech, service-oriented economy. Today, most Asian countries are trying to solve these problems by restructuring or reforming their education systems. The following article discusses the state of educational processes in the technical fields of higher educational institutions of the countries of the Commonwealth of Independent States. The results of the study show a high level of development of government strategies to maintain technological modernization of the country.

Abstract

The article is in line with the contemporary interests of companies from the aviation industry. It describes thermoplastic material and inspection techniques used in leading aviation companies. The subject matter of non-destructive testing currently used in aircraft inspections of composite structures is approximated and each of the methods used is briefly described. The characteristics of carbon preimpregnates in thermoplastic matrix are also presented, as well as types of thermoplastic materials and examples of their application in surface ship construction. The advantages, disadvantages and limitations for these materials are listed. The focus was put on the explanation of the ultrasonic method, which is the most commonly used method during the inspection of composite structures at the production and exploitation stage. Describing the ultrasonic method, the focus was put on echo pulse technique and the use of modern Phased Array heads. Incompatibilities most frequently occurring and detected in composite materials with thermosetting and thermoplastic matrix were listed and described. A thermoplastic flat composite panel made of carbon pre-impregnate in a high-temperature matrix (over 300°C), which was the subject of the study, was described. The results of non-destructive testing (ultrasonic method) of thermoplastic panel were presented and conclusions were drawn.

Abstract

Noise generated by helicopters is one of the main problems associated with the operation of rotorcrafts. Requirements for reduction of helicopter noise were reflected in the regulations introducing lower limits of acceptable rotorcraft noise. A significant source of noise generated by helicopters are the main rotor and tail rotor blades. Radical noise reduction can be obtained by slowing down the blade tips speed of main and tail rotors. Reducing the rotational speed of the blades may decrease rotor thrust and diminish helicopter performance. The problem can be solved by attaching more blades to main rotor. The paper presents results of calculation regarding improvement of the helicopter performance which can be achieved for reduced rotor speed but with increased number of rotor blades. The calculations were performed for data of hypothetical light helicopter. Results of simulation include rotor loads and blade deformations in chosen flight conditions. Equations of motion of flexible rotor blades were solved using the Galerkin method which takes into account selected eigen modes of the blades. The simulation analyzes can help to determine the performance and loads of a quiet helicopter with reduced rotor speed within the operational envelope of helicopter flight states.