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1

Comparison of Colour Properties of Polypropylene and Poly-(Lactic) Acid Fibres Dyed With Photoluminescent Dye

Ujhelyiová Anna, Jančovičová Viera, Panák Ondrej, Hrabovská Veronika, Tomčíková Zita

Fibres & Textiles in Eastern Europe

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2022

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Vol. 30, no. 5

17-27

EN

Every manufacturer wants to protect their textile products and their brand. A possible solution is, for example, the insertion of fibres with special pigments visible under irradiation by UV light into the final product. The paper focused on the study of the structure and colourimetric properties of polypropylene (PP) and poly-(lactic) acid (PLA) fibres modified with photoluminescent dye and halloysite (HNT) modified with photoluminescent dye. The photoluminescent dye and HNT modified with photoluminescent dye affected the structure of PP and PLA fibres differently. Increasing the HNT content up to 0.15 % increased the orientation of the PP fibres. In the case of PLA fibres, the increased content of photoluminescent dye in PLA fibres increased their orientation in the observed concentration area. PLA-based knitted fabrics showed better light stability, where there was no visible degradation of the knitted fabric, only its darkening. Likewise, PLA-based knitted fabric showed luminescence in UV light even after accelerated light aging.

2

Struktura mechaniczna i układ sterowania zrobotyzowanym montażem astronomicznym

Kozłowski K., Pazderski D., Krysiak B., Jedwabny T., Kozłowski S., Brock S., Janiszewski D., Nowopolski K.

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2018

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z. 196

5--14

PL

Praca przedstawia ogólny opis dotyczący projektowania zrobotyzowanego montażu teleskopu astronomicznego klasy 0,5 m. Scharakteryzowano strukturę mechaniczną i elektryczną urządzenia oraz jego elementy pomiarowe. Następnie przedstawiono algorytm sterowania osią wykorzystujący aktywną kompensację zakłócenia. Wyniki śledzenia trajektorii złącza obrotowego zbadano eksperymentalnie również w odniesieniu do przestrzeni zewnętrznej.

EN

In this paper, a short description of a robotised mount of the 0.5 m class astronomical telescope is provided. Mechanical and electrical parts of the mount and its measuring system are discussed. Next, an algorithm designed for motion control which is based on the active disturbance rejection paradigm is considered. In order to illustrate the performance of the closed-loop system, experimental results of trajectory tracking in the joint and the task spaces are compared.

3

The impact of the wheel rim contact with the rail on energy consumption

Bryk K., Łukaszewski K.

Pojazdy Szynowe

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2017

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Nr 2

62--69

EN

The article presents studies on the effect of change of the wheel flange friction coefficient with the rail on the rail vehicle energy consumption. It describes how to simulate the phenomena analyzed on the basis of the dynamics of rigid bodies connected with elastic elements. The wheel rail contact was simulated using the FASTSIM contact algorithm. The results relating to the drive through track curves of varying radii were presented.

PL

W artykule zaprezentowano badania nad wpływem zmiany współczynnika tarcia styku obrzeża koła z szyną na zużycie energii przez pojazd szynowy. Opisano sposób symulowania analizowanego zjawiska w oparciu o dynamikę brył sztywnych połączonych elementami podatnymi. Styk koło szyna zasymulowano przy użyciu algorytmu kontaktu FASTSIM. Przedstawiono wyniki odnoszące się do przejazdu przez łuki toru o różnym promieniu.

4

Structure modeling of the CLAAS ARION 620 road-rail shunting tractor

Medwid M., Stawecki W., Czerwiński J., Jakuszko W., Kazimierczak E.

Pojazdy Szynowe

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2017

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Nr 2

1--14

EN

The article presents the third-generation road-rail shunting tractor based on the CLAAS ARION 620 agricultural tractor. The mechanical, hydraulic and pneumatic structure of the tractor, traction parameters on the track, built-in traction system and the draw and buffer gears give it the characteristics of a universal vehicle designed for driving on roads as well as rail tracks with a normal gauge of 1435 mm or the 1520 mm wide track or a normal and wide track.

PL

W artykule zaprezentowano ciągnik szynowo-drogowy trzeciej generacji wykonany na bazie ciągnika rolniczego CLAAS ARION 620. Przedstawiono strukturę mechaniczną, hydrauliczną i pneumatyczną ciągnika, parametry trakcyjne na torze, zabudowany szynowy układ jezdny oraz urządzenia pociągowo-zderzne nadające mu cechy pojazdu uniwersalnego przeznaczonego do jazdy po drogach kołowych i torach kolejowych o normalnym rozstawie 1435 mm i na torach szerokich 1520 mm oraz na torach normalnych i szerokich.

5

First principles studies of SnO at different structures

Erdem I., Hüseyin Kart H., Cagin T.

Archives of Materials Science and Engineering

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2010

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Vol. 45, nr 2

108-113

EN

Purpose: Structural and mechanical properties of the Sn (tin) based oxides SnO and SnO2 are investigated. The aim of this study to determine in which structural phase SnO is found and to calculate its elastic constants at different pressures. Design/methodology/approach: Calculations have been made for three different structures of SnO by density functional theory (DFT). The behavior of structural parameters (lattice constants, internal parameters) and bulk modulus under different pressures, and elastic constants are calculated by using ab initio calculations. Generalized Gradient Approximation (GGA) and Perdew-Burke-Ernzerhof (PBE) parameterization is used. Findings: All of six elastic constants of litharge SnO and three elastic constants of rocksalt structure of SnO are calculated for the first time in this study. Among three structures of SnO, namely, rocksalt, cesium chloride and tetragonal litharge, the most energetically favorable one is the litharge structure at ambient conditions. The calculation of enthalpies with respect to pressure shows that any phase transition from litharge to rocksalt structure does not occur by applying the pressures of up to 5 GPa to the systems. Equilibrium volume, energy and bulk modulus of rutile SnO2 are also calculated. Our results are compared with other available experimental data and theoretical results. Research limitations/implications: Computer calculation speeds and its information storage area are limitations, it will be possible to reach experimental results as near as in condition that they are improved. Practical implications: It is very difficult to measure elastic constants especially under high pressure experimentally. However, they are calculated by first principles calculations. Originality/value: Behavior of elastic constants and structural parameters under high pressures are determined for the first time in this study. Simulations can lead experimentalist to find new applications of these technologically important materials.

6

Magnetorheological dampers in vibration control of mechanical structures

Sapiński B.

Mechanics / AGH University of Science and Technology

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2009

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Vol. 28, no. 1

18-25

EN

The paper summarizes the experimental data gathered during the laboratory tests of vibration control of three mechanical structures utilizing magnetorheological (MR) dampers. The author's research program involved the investigations of the structures. The first application refers to vibration control in a driver's seat suspension (structure 1). The control objective is to reduce vertical acceleration of the driver. The second application covers vibration control in a pitch plane vehicle suspension (structure 2). The control objective is to reduce vertical and angular accelerations of the vehicle. The third application concerns vibration control of a suspended cable (structure 3). The control objective is to reduce transverse free vibrations of the cable. The obtained results demonstrate system performance improvement achieved through the control of MR damper(s).

PL

W artykule podsumowano wyniki badań laboratoryjnych prowadzonych pod kierunkiem autora nad sterowaniem drganiami trzech struktur mechanicznych z zastosowaniem tłumików magnetoreologicznych (MR). Pierwsza aplikacja dotyczyła sterowania drganiami zawieszenia fotela kierowcy (struktura 1). Celem sterowania była redukcja przyspieszenia drgań kierowcy. Druga aplikacja dotyczyła sterowania drganiami zawieszenia pojazdu (struktura 2). Celem sterowania była redukcja przyspieszenia drgań pionowych i kątowych pojazdu. Trzecia z aplikacji dotyczyła sterowania drganiami zawieszonej liny (struktura 3). Celem sterowania była redukcja drgań swobodnych liny. Wyniki eksperymentów wykazały skuteczność tłumików MR do sterowania drganiami badanych struktur.

7

An intelligent computing technique in identification problems

Orantek P.

Computer Assisted Mechanics and Engineering Sciences

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2006

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Vol. 13, No. 2

351-364

EN

The paper is devoted to the application of the evolutionary algorithms, gradient methods and artificial neural networks to identification problems in mechanical structures. The special intelligent computing technique (ICT) of global optimization is proposed. The ICT is based on the two-stage strategy. In the first stage the evolutionary algorithm is used as the global optimization method. In the second stage the special local method which combines the gradient method and the artificial neural network is applied. The presented technique has many advantages: (i) it can be applied to problems in which the sensitivity is very hard to compute, (ii) it allows shortening the computing time. The key problem of the presented approach is the application of the artificial neural network to compute the sensitivity analysis. Several numerical tests and examples are presented.

8

Modelowanie, analiza oraz synteza aktywnych układów mechanicznych

Buchacz A., Żurek K.

Zeszyty Naukowe. Mechanika / Politechnika Śląska

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2005

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z. 152

99-122

PL

Zasadniczym celem podejmowanej pracy jest opracowanie metody poszukiwania struktury oraz parametrów, czyli syntezy strukturalnej i parametrycznej dyskretnego modelu układu mechanicznego z elementami aktywnymi, na podstawie żądanych wymagań. Wymagania te dotyczą własności dynamicznych układu, a w szczególności ich widma częstości.

EN

The principal aim of the research taken is to work out a method of structure and parameters searching i.e. structural and parametric synthesis of discrete model of active mechanical system on the base of desired requirements. The requirements refer to dynamic features of the system, particularly their frequency spectrum.

9

Gridy obliczeniowe w zagadnieniach optymalizacji i identyfikacji układów mechanicznych

Kuś W.

Zeszyty Naukowe. Mechanika / Politechnika Śląska

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2005

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z. 152

41-57

PL

W artykule przedstawiono metodę optymalizacji i identyfikacji układów mechanicznych z wykorzystaniem algorytmów ewolucyjnych i gridów obliczeniowych. Przedstawiono przykłady numeryczne uzyskane z wykorzystaniem środowisk Condor oraz UNICORE.

EN

The optimization and identification of mechanical structures based on evolutionary algorithms and computational grids are presented in the paper. The numerical examples obtained using Condor and UNICORE environment are shown.

10

Identyfication pf loads in mechanical structures-helicopter case study

Uhl T.

Computer Assisted Mechanics and Engineering Sciences

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2002

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Vol. 9, No. 1

151-160

EN

This paper presents possibility of identification of loads in mechanical systems based on response measurements during operation. Information of loads is very useful in diagnostic process, if usage of structure is under investigation. State of the art in the field of loads identification is presented. The problem of load identification is defined, and some methods are presented. The paper is focused on the problem of loads identification based on measurements of process parameters or movement parameters for vehicles or airplanes. Two methods are applied to show applicability of this approach in industrial practice; neural network based method and regression model based method. A case study of identification of load of helicopter structure during flight is presented.

11

Realizacja fizyczna syntezowanej charakterystyki w ujęciu grafów

Buchacz A., Dymarek A., Dzitkowski T.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2001

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z. 17

13-18

PL

Przedstawiona praca dotyczy sformułowania zadania realizacji fizycznej poprzez graf, charakterystyki dynamicznej. Tak określony graf charakterystyki dynamicznej stanowi podstawę do przedstawienia struktury dynamicznej układu mechanicznego.

EN

The presented paper concerns the formulating the task of physical realization of a dynamical characteristics with the aid of a polar graph. The resulting polar graph of a dynamical characteristics is a basis of the presentation of the mechanical system dynamical structure.

12

Optimization of mechanical structures using interval analysis

Pownuk A.

Computer Assisted Mechanics and Engineering Sciences

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2000

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Vol. 7, No. 4

699-705

EN

The problem of optimal design consists in finding the optimum parameters according to a specified optimality criterion. Existing optimization methods [1,2] usually are not reliable or cannot use the nondifferentiable, not continuous objective functions or constraints. An interval global optimization method is very stable and robust, universally applicable and fully reliable. The interval algorithm guarantees that all stationary global solutions have been found. In this paper the algorithm is applied to optimization of mechanical systems, calculation of extreme values of mechanical quantities and to optimization of structures with uncertain parameters.

13

Analysis of linear mechanical structures with uncertainties by means of interval methods

Kulpa Z., Pownuk A., Skalna I.

Computer Assisted Mechanics and Engineering Sciences

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1998

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Vol. 5, nr 4

443-477

EN

One of the simplest ways of representation of uncertain or inexact data, as well as inexact computations with them, is based on interval arithmetic. In this approach, an uncertain (real) number is represented by an interval (a continuous bounded subset) of real numbers which presumably contains the unknown exact value of the number in question. Despite its simplicity, it conforms very well to many practical situations, like tolerance handling or managing rounding errors in numerical computations. Also, the so-called alfa-cut method of handling fuzzy sets membership functions is based on replacing a fuzzy set problem with a set of interval problems.