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Abstract

This paper demonstrates kinematic analysis of multiple trailers on a tractor system for production logistics. The analysis concerned three different steering systems of the trailers: virtual clutch and drawbar system, conventional clutch and drawbar system, double Ackermann steering system. Designed kinematic models contain various variants of paths: turning at a constant value of the steering angle, changing the steering angle as a result of an approaching collision. Each of these variants also included driving in a straight line after a 90° turn. The validation of the developed kinematic model was done by using a real logistic train, which path was registered via aerial drone. For each of the developed kinematic models, a visualization of drive through the 90° turn was created.

Abstract

In this paper researches which focus on laser heat treatment of nickel-based alloys are reviewed. Studies published from 1970s until today are taken into consideration. Publications which focus on influence of laser thermal processing on surface layer condition both on solid materials and pre-deposited coatings are described. Laser technologies in which additional materials are delivered during the process are not considered. In order to focus on studies investigating microstructural changes resulting mainly from material remelting, laser shock processing is also disregarded.

Abstract

Geothermal investments change both the natural and the built environment. They affect water resources under the Earth’s surface as well as the natural landscape itself. Regulations of authority permit procedures apply to various subunits of the environment and occur at certain stages of the investment. This paper examines how transparent and consistent regulations are as well as what difficulties the investors could have during the different authorisation processes, which could influence the implementation of the project. Process analysis was used to examine domestic and international regulatory practices. We examine the stages where the required authorisation procedures for the construction of geothermal investments occur in the implementation process and what role the individual permits play in the process of the investment. The research found that the authorization process is extremely long and very complicated.

Abstract

The subject of the article is an attempt to determine the impact of the applied measurement strategy on the accuracy of the measurement result. This problem is particularly crucial when measuring large objects. In these cases, it is not always possible to provide ideal conditions for the submission of particular scans. It is necessary to adjust the strategy to specific imposed conditions defined by the geometry of the object and to the time frame of the measurement itself.

With regard to the above, an attempt was made to carry out a series of accuracy studies testing the structural light scanner while measuring elements of overall dimensions greater than the measuring capacity of the scanner. At the same time, various potential measuring strategies were simulated in practical applications. Our studies were conducted using a pre-designed test template with a defined distribution pattern of reference points and geometrical elements. Moreover, in order to make an in-depth investigation of the issue, some trials were undertaken with the use of limiting parameters. That means the scanner had both an excess and shortage of information required for a correct assembly of scans. Those scopes were taken into consideration in the study in order to use the acquired knowledge in practical measuring applications. Furthermore, conclusions from the conducted studies indicate peaks and troughs of respective measuring strategies with special care for determining relationships among the used strategies and the measuring accuracy parameters.

Abstract

The shape and type of chip give general information about the cutting process. This paper presents the results of testing the shape and type of chips of Ti6Al4V titanium alloy after it finishes turning. The process was carried out under dry, wet and MQL (Minimum Quantity Lubrication) conditions at variable cutting speeds and feed rates and a constant depth of cutting. For planning the tests, the PSI (Parameter Space Investigation) method was used, which allows the experiment to be carried out while minimizing the number of experience points. It was found that the cutting speed and feed affect the type and shape of the chip, and clear differences were observed between dry and wet cooling conditions, and MQL conditions. During turning, the intensity of the cutting speed and feed influence on the chip compression ratio was changed. It was similar for dry and wet cooling conditions but smaller for MQL conditions. The purpose of this research is to analyze the chip shaping when Ti6Al4V titanium alloy finishes turning under dry, wet and MQL cooling conditions.

Abstract

Ernő Foerk’s most well-known work in architectural circles is certainly the volume published in the reprint edition, which collects the material of the building surveys conducted by the students of the Hungarian Royal Public Higher Architectural Industrial School between 1912-1942. The introduction to each volume shows that he considered to document the buildings as the main task of the surveys - besides their role in education - and thus to serve the Hungarian culture. Architectural surveying is still one of the most important starting points for monument reconditioning. Ideally, the process of monument reconditioning consists of the following steps: Scientific Research - Pre-planning Technical Studies – Compilation of a Planning Program and Planning - Professional Authority Control (getting of building permission) – Building Construction Work and (Fine Art) Restoration - Maintenance. This paper presents the essential role of surveying in this process.

Abstract

After many years of intensive work the international experts from ISO TC 39 published the technical report called ISO TR 16907 “Machine tools – numerical compensation of geometric errors”. This document defines the terminology, presents benefits and limitations of numerical compensation of machine tools’ and measuring machines’ errors. It gives machines manufacturers and users vital information about how to use numerical compensation. In the context of those types of compensation defined in ISO TR 16907, this article shows rules of selecting models of Volumetric Error for three-axis machine tools. What is more, this paper presents some principles of reduction of these proposed models because of the functional tasks for machine tools. One of the obtained results is an array of reduced models for three-axis machine tools. This array determines the degree of detail of the model and the experimental research program that needs to be carried out in order to determine the Volumetric Error distribution.

Abstract

Ernő Foerk (1868-1934) born 150 years ago has significant oeuvre in the field of monument preservation and architectural education. As professor, one of his achievements was the organisation of summer survey camps named as ‘szünidei felvételek’ (vacation records) which was also accessible in published form. In the year of 1917 under his supervision, his students have surveyed all the scored Ottoman monuments of Hungary. In the following year these survey drawings were published with a brief summary of the history of Ottoman architecture in the territory of Hungary. Our paper is to submit the general circumstances of the Ottoman survey program supervised by Ernő Foerk with its historical background and the analysis of the methodology of the survey by the example of the türbe of Pécs.

Abstract

Present paper is about Ernő Foerk’s several architectural works which involved monument preservation. Questions about the theory and practice of monument preservation are surveyed, focusing on restoration and reconstruction in Hungary in the marked period.

Abstract

Architects Aladár Árkay and Ernő Foerk crossed the path reasonable few times, even though their course of life were parallel. Not only the place, but also the date of their birth were quite close. This fact will be the starting point to compare the two architects’ career.