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Number of results: 45
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Abstract

There exist numerous modelling techniques and representation methods for digital control algorithms, aimed to achieve required system or process parameters, e.g. precision of process modelling, control quality, fulfilling the time constrains, optimisation of consumption of system resources, or achieving a trade-off between number of parameters. This work illustrates usage of Finite State Machines (FSM) modelling technique to solve a control problem with parameterized external variables. The structure of this work comprises six elements. The FSM is presented in brief and discrete control algorithm modelling is discussed. The modelled object and control problem is described and variables are identified. The FSM model is presented and control algorithm is described. The parameterization problem is identified and addressed, and the implementation in PLC programming LAD language is presented. Finally, the conclusion is given and future work areas are identified.
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Abstract

The purpose of the work was initial modification of the construction of a commercially produced heat exchanger – recuperator with CFD (computational fluid dynamics) methods, based on designs and process parameters which were provided. Uniformity of gas distribution in the space between the tubes of the apparatus as well as the pressure drop in it were taken as modification criteria. Uniformity of the gas velocity field between the tubes of the heat exchanger should cause equalization of the local individual heat transfer coefficient values and temperature value. Changes of the apparatus construction which do not worsen work conditions of the equipment, but cause savings of constructional materials (elimination or shortening some parts of the apparatus) were taken into consideration.
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Abstract

This paper examines the coverage of women’s health issues, preventive care and prophylaxis in 19th-century Polish popular medical periodicals, in particular Dziennik Zdrowia dla Wszystkich Stanów [ Journal of Health for all Social Classes] (1801–1802), Przyjaciel Zdrowia [ Health’s Friend] (1861–1863), Zdrowie [ Health] (1877/78–1880), and Lekarz [ The Physician] (1903/04–1904/05). The authors of this study try to find an answer to the question whether those periodicals did succeed in giving women’s health issues the rank and status warranted by their significance.
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Abstract

This article outlines the rise and development of popular science periodicals in Poland from the 18th century until 1939. Their history begins in 1758 with the publication of Nowe Wiadomości Ekonomiczne i Uczone [Latest Economic and Learned News]. Our corpus includes 128 periodicals representing a great diversity of formats and content.
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Abstract

The paper presents the possibilities of quantitative analysis of results obtained from CT examination of organs and anatomical structures of the upper respiratory tract. The presented results of the analysis were obtained using proprietary software developed in the MATLAB 2018b environment (Image Processing toolbox). The software enables to visualize the original results of CT scan and, after evaluating the visible structures, enables to select the area to be subjected to quantitative analysis. After the initial identification of an area of interest requiring detailed diagnostics, its volume and the surface areas of individual cross-sections are calculated in the area separated for examinations. A graphical presentation of the analysis results – the surface areas of selected cross-sections possible to visualize in two- and three-dimensional space – enables quick analysis of changes in the examined region.
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Abstract

In this paper we describe our own construction of a tuneable light source based on a set of light emitting diodes covering the visible spectrum using a homogenizing rod instead commonly used low energy-efficient integrating spheres. The expected prime application of the source is a medical endoscopic system, however it is possible to use it also for other purposes requiring both multispectral operation and a tuneable white light source. We describe the construction of the source and include precise characterization of the output white light – distribution of CCT, Duv, Δu′ v ′ and colour rendering indexes (Ra, R9, Rf , Rg) of light in several planes located at various distances. The obtained results prove that our source is characterized by very good colour rendition according to the Ra and Rf method for various correlated colour temperatures (2700–6500) K. As an example of application images of the Macbeth colour chart registered with an RGB camera included in the laboratory measurement stand are presented. The obtained results prove that, after whole system calibration, this source can be used in many applications, where evaluation of objects requires precise analysis of their colour and multispectral procedures.
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