Technical Transactions. Vol. 4

Technical Transactions. Vol. 4

Type: Collection of magazine numbers
Release date

Collection items (21)


A mathematical model of accident event development in the construction industry

Hoła, Bożena, Szóstak, Mariusz
Article
2017
Accidents at work constitute a heavy psychological and economic burden for companies and societies. The vast majority of cases can be prevented by appropriate and effective preventive measures. Knowledge about the course of events, their causes and consequences is required in order to carry out such actions. The knowledge gained can provide a basis for drawing conclusions of a preventive nature. The article presents a mathematical model, which was used in the study of the phenomenon of accidents in the construction industry, and provides the test results that were obtained using 350 sample cases.

The pressure and the vibration measurement in automotive shock absorbers

Sikora, Marian
Article
2017
The purpose of this article was to develop a measurement system for analyzing the dynamic behavior of automotive hydraulic dampers as well as to examine the internal pressures in each hydraulic chamber of the damper. Dampers are one of the components of the vibration/noise system that originates at the contact point/surface between the wheel and the road, and then ends at the body of the vehicle. Specifically, dampers are often a source of flow-induced or motion-induced noise due to the operation of the valves. In this paper, measurement results are presented in the form of time histories of the internal pressures and piston rod acceleration, respectively. Fast Fourier Transform (FFT) graphs are also presented in order to identify the major components of the phenomena under investigation in a frequency domain.

1960’s polish modernistic industrial buildings today

Bardzińska-Bonenberg, Teresa
Article
2017
The 1960s in Poland was a period when formal boundaries of the Stalinist period were being shaken off. The economy, with its reliance on heavy industry, was in dire need of new production facilities, the shape of which was dictated by the available technology. The mounting restrictions imposed by the centrally controlled state and changing investment priorities did not affect production undertakings inasmuch as other construction industry disciplines. At that time, equipment and industrial unit designs were not subject to categorisation yet, and furthermore enjoyed privileged status when it came to acquiring building materials. Such a situation gave designers a free run at shaping their creations to accommodate technological requirements and in accordance with the modernistic line. Numerous outstanding examples of industrial architecture were created, constituting an important element of the Polish post-war architecture. Unfortunately, only a few survive to this day.

Light sources and their influence on vision organ

Otowski, Wojciech, Lewińska, Gabriela
Article
2017
The aim of the study was to compare light sources. The paper presents the spectrum of light intensity for natural and artificial sources. Analysis of the spectra was carried out because of their importance for the health of the eye.

Influence of non-uniformity of cracking on calculation of deflection of reinforced-concrete elements, according to Eurocode 2

Szeptyński, Paweł
Article
2017
Formulae for the deflection of two examples of isostatic systems (simply supported beam, cantilever) were derived, accounting for influence of distribution of bending moments on cracking and beam stiffness distribution, according to EC2. Numerical analysis of the problem for the same two examples as well as for two further hyperstatic systems was performed using an iterative FEM algorithm. The influence of nonuniformity of cracking on deflection and distribution of bending moments was shown to be negligible in typical practical design problems, therefore also an estimation of deflection on the basis of the distribution of bending moments and the value of the factor αk obtained from linear solution (before redistribution) is shown to be justified.

Mathematical modeling of heat and mass transfer of particles encapsulation in a fluidised bed

Lipin, Aleksandr G., Lipin, Andrey A., Wójtowicz, Ryszard
Article
2017
The mathematical model, which allows to predict changes of the coverage degree, the moisture content and temperature of particles in process time, was developed. Taking into account changes of the evaporation surface due to an increasing particles coverage degree in the encapsulation process allows to describe the evolution of particles parameters more adequately and to select of process rational parameters.

Technical Transactions. Vol. 4

Number of the magazine
2017

Challenges in takeoffs and cost estimating in the BIM technology, based on the example of a road bridge model

Gołaszewska, Małgorzata, Salamak, Marek
Article
2017
Technical and economic analysis of a construction project carried out using BIM can improve the process of cost-estimating at all stages of design and construction works. More and more designers choose to use BIM within a range of cost estimates; however, in contrast to design software, cost-analysing BIM software is less widespread and used. The following paper presents problems and issues that could be encountered while performing cost estimates and quantity takeoffs applying BIM tools on the example of a model of a road bridge.

Heat transfer during storage of hot liquid in the tank

Neupauer, Krzysztof, Kupiec, Krzysztof
Article
2017
In the article, a mathematical model of heat transfer in a storage tank for hot water with a non-uniform initial temperature is presented. The influence of the initial temperature distribution of the liquid in the tank and the influence of thermal resistance of the tank’s walls, bottom and cover on temperature profiles of the liquid in the tank and changes of these profiles in time were analysed. A good conformity of the results obtained based on the process model with the results of measurements of water temperatures carried out under laboratory conditions was obtained.

Generation of homo- and heterogeneous microcapsules and their application

Semba, Damian, Trusek-Hołownia, Anna
Article
2017
Microencapsulation is defined as a process during which the whole envelopment with (bio)catalysts, substrates etc. is included into hydrogel and/or surrounded by a porous polymeric membrane. However, the production of homogeneous, narrow size, distributed capsules is quite troublesome. The main problem is the way of obtaining a large number of capsules with a precisely predefined size. It is possible due to a device called an encapsulator. This equipment allows to produce homogeneous beads and core-shell systems with a predefined size in the range from 400 μm to 1600 μm, which is possible because of special nozzles with different diameters. There are a lot of microcapsule applications. In this paper, we would like to present the construction, principles of operation and selected applications of microencapsulation devices using the example of the BÜCHI–B390 encapsulator.