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Abstract

The Electrochemical discharge machining (ECDM) is a hybrid non-traditional process which is specifically used for machining of conducting as well as non-conducting materials. In this research work, the fabricated ECDM experimental setup was used to machine the Soda-lime glass material with Brass tool material. The experiments were done on Soda-lime glass material with the help of Taguchi L27 orthogonal array method and analysed by using MINITAB 17 software. The average hole diameter and average machined depth results were checked after ECDM drilling on Soda-lime glass material with considering the input process parameters such as an electrolyte concentration, voltage and rotation. The experimental results indicated that voltage was the most dominant factor for average machined depth followed by an electrolyte concentration and rotation speed. The rotation speed was the most dominant factor for average hole diameter followed by voltage and electrolyte concentration.

Abstract

The sliding strip of the current collector (pantograph) of a rail vehicle is an element directly cooperating with the catenary and is exposed to abrasion, electric discharge and various types of damage. It is therefore the most frequently replaced element. However, often sliding strips are exchanged before exceeding the limit thickness value, which increases the costs related to technical maintenance. Because the wear process is dependent on many factors, heuristic methods are necessary to predict the thickness of the sliding strip. Knowing the predicted thickness value, it will be possible to adapt the maintenance cycle. In the article, the results of simulations carried out based on the developed structure of the artificial neural network are also presented.

Abstract

The paper focuses attention on the problem of increased risks during the loading and unloading of railway tankers. To evaluate the risk which may occur during loading dangerous goods into tanker trains, the loading processes have been divided into seven stages. Based on HIRA risk analysis, for each stage of improvements, Quick Kaizen tasks were proposed. Special attention was paid to possible improvements in technical means, tools and processes. Thanks to the proposed improvements, it is possible to increase safety, not only during the loading of dangerous goods, but also in cases of loading and transportation of standard cargoes.

Abstract

Decision making in material selection plays important role in selecting appropriate material based on design and manufacturing attributes. Proposing a new material is always a challenging task so the researchers used Decision making assistance tools. In the Present paper the application of Multi-Attribute Decision Making (MADM) methods are applied to the piston material selection for optimal design process. Comparative study of subjective and objective criteria weights on selected MADM methods are done. Sensitivity analysis is conducted to prove the consistency in performance score ranking order as the criteria weights for each alternative varies.

Abstract

This article is aimed at providing a rationale for the need to introduce a new type of educational institution in Ukraine today, namely educational centers in the areas with challenging topography. This article identifies specific features of construction, given the difficult geographic topography and architectural environment of the educational institutions, and lists conditions impacting the volume and planning of educational facility construction. It defines how urban planning of school centers influence the areas with difficult topography and establishes their location type. The authors analyzed architectural and construction solutions for school centers in areas with challenging landscape. They have also identified form-shaping types of buildings and established the best slope ratio for each of the types.

Abstract

New trends in sustainable design contribute to prevention of the deterioration of the natural environment and they are focused on the optimisation of the indoor environment for the improvement of the human life quality. There are complementary goals of sustainable design – the comfort of architecture users, proper spatial planning, and, as a priority, taking into account the needs of both contemporary and future generations. These existential needs are connected with both local and global sozological problems. These are related to the continuing growth of irreversible changes to the environment, such as climate change, the disappearance of biodiversity, and the over-exploitation of nonrenewable sources of energy as result of shortsighted economy. These imply the necessity for the sozological education in all subjects of study and transdisciplinary training focused on the solving of problems associated with sustainable development.

Abstract

Chlorofluorocarbons and hydro chlorofluorocarbons (HCFCs) are replaced by hydroflourocarbons (HFCs) which is not harmful to the ozone layer. However, few of HFCs have a relatively high global warming potential (GWP) and are subject to further examination due to growing concerns about global climate change. The goal now is to find the next generation of environmentally sustainable work fluids with an insignificant direct environmental impact in terms of ozone depletion and global warming potential. This document introduces the mixture of low-GWP refrigerants like R440A, R430A, R1234ze (E)/152a (50:50 by mass), R290/600a (40/60), R290/600(60/40), R290/600(50/50), ARM 42,ARM 42a and AC5 are used to replace R-134a in a domestic refrigeration system without doing any modifications to the system. The performance of the refrigerator was observed in terms of volumetric cooling capacity, blower discharge temperature, and coefficient of performance, refrigeration effect and energy consumption of a blower.

Abstract

One of the key reasons behind the urban sprawl process is the desire to increase the quality of life by living in “better” conditions. “Smart growth” is an alternative concept for the extensive development of the city, integrating different ways of land development in a compact manner. The main current of the work is to reflect on the quality of life in the urban areas. The aim of research is to determine ways to “heal” the spatial development of urban and suburban areas under the existing conditions of increasing urban chaos. The interpretation of living conditions for particular social groups is needed to find solutions that increase the quality of life. The background to the research is an analysis of literature on the subject, the consideration of good examples and own observations.

Abstract

The results of research into two city gates, Kłodzka and Wodna (Water), and into the Rycerska (Knight’s) Tower in Bystrzyca Kłodzka are discussed in this paper. The research into the architecture of the three structures helped review the chronology of transformations they were subjected to between the beginning of the fourteenth century and the second half of the twentieth century. The city walls, together with the two gates and the tower, were probably erected by Alderman Jakub Rücker in the first half of the fourteenth century. All the towers were probably raised and converted in the fifteenth century and in around 1568, they were topped with masonry pyramid cupolas. The work performed in the nineteenth century was aimed at restoring the damaged elements and at introducing bells to the Rycerska (Knight’s) Tower. The conservation work conducted in the years 2013–2017 resulted in the restoration of the damaged details and in the enhancement of all of the structures’ features of historical value.

Abstract

The aim of this study was to document spatial changes in the size of the Spa Park in Inowrocław from the 19th century onwards based on archival maps as well as field research and observations of the current status. Towns providing a highly specialised health resort and spa services, such as Inowrocław, need large expanses of green areas as public spaces for outdoor therapy for spa town visitors and patients. In Inowrocław, this may not be limited only to the surroundings of the greatest asset of this spa town - its graduation towers. The fascinating history of the area and planning decisions concerning green areas over the years have brought many benefits to the town, which also extend outside the scope of health resort services. This article presents the multi-faceted changes and transformations of this area along with the plans and intended uses.