Volume 115 (2018): Edizione 12 (December 2018)

The article is devoted to the visual perception of selected architectonic objects and urban space in the health resort in Rabka-Zdrój. Eye-tracking research was presented in its theoretical aspect, and then results of research carried out using a stationary eye-tracker were also presented. An analysis of experiment results allowed for determining the usefulness of eye-tracking research in learning the range and manner of perceiving architectonic objects and urban spaces by people looking at them. The usefulness of the discussed research in working out assumptions and activities related to protecting historic objects and spaces as well as educational activities was indicated.

Futuristic concepts of housing environments show people, how it will be possible to live in the near future. These projects inspire engineers, scientists and researchers who bring modern technologies to life. It seems that technology is the key to solving the problems that humanity faces today. Housing environments need a new interpretation adapted to contemporary people who are looking for a new quality of living. In the article, the author will characterize futuristic visions of housing in the future, based on their location: on land, underground, in the air, under or on water.

The paper describes the forgotten realization of the forgotten creator – Edgar Kováts, a Polish architect of Hungarian origin, operating at the turn of the 19th and 20th centuries in Vienna, Zakopane and Lviv, the rector of the Lviv Polytechnic. The neo-baroque church in Mystków was the subject of research and inventory using a laser scanning as well as design work carried out by the author of this paper.

The article deals with the problem of increasing demand for modular buildings as an answer to the construction industry’s current situation. The author addresses the following question regarding the near future of the modular construction industry: How would it reflect on urban space, living space and the whole attitude toward modular construction issues? What is the role of the architect during the design–build process? Is it possible to make references to “beauty” in a modular construction context?

The paper presents results of numerical analysis of the gabion retaining wall stability. A few of the possible design variants were analyzed and the optimal one was chosen.

The specifics of a forecast fire development in a single fire compartment consisting of a shopping hall characterised by a large area and a relatively low height are analysed in this paper. The fire initiated locally, and after initiation, depending on the ventilation conditions in the zone, more or less intensively spread to the neighbouring areas with or without full development. The propagation of hot exhaust plume was simulated within the environment of the FDS computer code. Three formal models differing in zone size and stacking height have been subjected to analysis. The influence of automatically activated smoke vents has been accounted for.

The paper presents an example of the determination of moment resistance for a liner tray restrained by sheeting according to the rules given in standard PN-EN 1993-1-3 [12].

This paper presents an approximate method for a groundwater flow analysis in the case of a slope with vertical dewatering wells distributed equidistantly. Firstly, a multi-scale problem of flow to a drainage well is solved and flow model to a perforated tube with a filter screen is shown. Secondly, a method of building quasi-3D flow model of a slope with vertical dewatering wells using a technique of overlapped 2D mesh is shown. A short description of the implementation of this 2D/3D flow model for the ZSoil.PC code is given. The results of the described 2D/3D method are compared with a referential 3D analysis giving an acceptable level of agreement. Finally, the 2D/3D method of flow analysis is used in a two-phase (flow + deformation) formulation of a slope stability problem. The comparison of the results of these analyses with fully 3D (referential) analysis, on an example problem provides a very close accurate stability and deformation estimation; however, the computational time used for the 2D/3D analysis is significantly shorter than required by 3D analysis.

When observing the stability of suspended ceilings during operation, sometimes smaller failures are observed, up to disasters, even a few of considerable sizes and serious consequences. The aim of the article is to analyse the causes of damage to a suspended ceiling, with an area of approximately 500 m², as well as testing and checking the applied construction elements. In situ destructive tests as well as tests at the AGH laboratory were carried out. The analyses were carried out in accordance with PN/EN 13964: 2014 (E). It was found that the designed ceiling system solution was correct. Whereas in the performance, an improper spacing of hangers, even by more than 70% of the permissible spacing, and forbidden lengths of brackets from C60 profiles, were applied. Also, about 55% of the connectors had too small diameters of the ends of the mandrels, which allowed for the sliding of broken head and a sudden loss of carrying capacity of the hanger.

This paper presents a new method for passive current compensation of a real multiharmonic power source with the use of a four-terminal network. In contrast to a two-terminal compensator, a four-terminal-network compensator can fully separate the supply circuit from the load. This ensures optimal operating conditions for the source while keeping the voltage and load current unchanged. The source’s optimal working conditions mean that the source current reaches its minimal RMS value (becoming the so-called “active current”) while it transmits the desired active power to the load.

This article presents investigations performed on a 25 kV AC system with a Scott transformer simulation model. The model includes an energy quality parameter calculation algorithm with consideration to the train timetable. The simulation results enable an analysis of the energy quality parameters at the point of connection of the traction substation to the supplying grid. The presented tool enables the simultaneous calculation of voltage unbalance and harmonic content. The article presents the results of the energy quality analysis at the substation connection point for the specific location. The simulation results of the energy quality parameters are appraised on the basis of standard EN 50160:2010. The tool may prove helpful in the process of designing electrification systems, especially in the choice of traction transformer and power electronics device mitigating an imbalance and harmonic impact.

This paper presents considerations on selected methodological aspects of respirometric COD fractionation in industrial wastewater which may differ from more common applications of such methodology for municipal wastewater. This concerns: the presence of interfering substances; problems with the elimination of nitrification; the importance of recognising biomass metabolism; differences of growth coefficient; the inclusion of non-canonical COD fractions and toxic effects. The discussion is based on a literature review and the authors’ own experience. As a conclusion, a preparatory procedure is proposed to assure the correct performance of respirometric COD fractionation for industrial wastewater, especially for more complex chemical effluents.

This paper analyses the option of using pressure signal new descriptors for controlling a selected object. Pressure signal deviations from the pressure mean values were selected to be the example descriptors. Diesel fuelled with mineral- and bio-fuels was chosen to be the reference object. The in-cylinder pressure signal (p_c) was recorded during the combustion process.

The article presents problems of maintaining the Z-type supply pumps and network operated in ENEA Wytwarzanie Sp. z o.o. Heat Segment, Białystok Branch with the use of thermovision and vibrodiagnostic studies. The practical aim is to select parameters of the supply pumps (multistage) which ensure energy efficient operation despite a serious operational wear - a 20-year working period. Commissioning of a Z-type feed pump and thermovision tests of selected machine construction elements constituted the subject of the research.

This paper shows a parameters selection method providing an ablative laser treatment removal of materials. A laser for generating laser beams of ultraviolet light in picosecond pulses at a frequency to 400 kHz was used in the experiment. The quality of the marks was examined by scanning electron microscopy. On the basis of the analysis, it is recommended to conduct micromachining at a frequency of 100 kHz and exposure times within the range of 62.5 ms to 125 ms.

The paper presents selected test results of the PERKINS 1104D-E44TA engine, adjusted to being dual-fuelled with compressed natural gas and Diesel fuel. The tests were carried out with maximum possible dosing of natural gas and then with lowering its dosing by approximately half. The obtained test results were compared with the results of tests carried out when the engine was powered with Diesel fuel only.

The article presents a method for optimizing technological parameters utilizing the G. Taguchi procedure. Optimization algorithm of controlled variables was presented in order to obtain the greatest value of nanohardness, microhardness and elastic modulus.

The paper presents experimental results that concern cold longitudinal rolling of flat bars made from EN AW-6063 aluminium alloy. The investigations aimed at determining the impact of the degree of deformation of material on the forward slip. The forward slips were calculated from Fink’s, Drezden’s and Vinogradov’s formulae. On the basis of investigations of the cold longitudinal rolling of flat bars made from aluminium EN AW-6063, it was found that the forward slip increases with an increase in degree of deformation of material.

The paper presents the issue of boiling heat transfer enhancement with the use of different passive techniques, namely the application of wire mesh coatings, capillary porous layers, pin – fins and laser treatment. Enhanced boiling heat transfer has been described as well as the research data of the authors that deals with microstructural coatings. The conducted experimental tests confirm the possibility of increasing heat fluxes transferred at the same superheat value due to the use of heat transfer enhancing techniques.