Wyniki wyszukiwania - Biblioteka Nauki

1

Stabilization of Inertial Plant with Time Delay Using Fractional Order Controller

100%

Ruszewski A. , Nartowicz T.

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tom Vol. 5, no. 2

117-121

EN

The paper presents the problem of designing of a fractional order controller satisfying the conditions of gain and phase margins of the closed-loop system with time-delay inertial plant. The transfer function of the controller follows directly from the use of Bode's ideal transfer function as a reference transfer function for the open loop system. Using the classical D-partition method and the gain-phase margin tester, a simple computational method for determining stability regions in the controller parameters plane is given. An efficient analytical procedure to obtain controller parameter values for specified gain and phase margin requirements is also given. The considerations are illustrated by numerical examples computed in MATLAB/Simulink.

2

Transient vibration of unsteady linear closed loop systems

100%

Wittbrodt E. , Kaliński K. J.

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tom Vol. 47, iss. 3

247-268

EN

A problem if unsteady linear closed loop system vibration is formulated and solved in this paper. Proportional, ideal derivative and delayed feedback interaction is considered. The mixed method of rigid and deformable finite elements is extended by including coupling elements, and applied to modelling the system. An unconditionally stable numerical integration variant of the Newmark method is used for solving the problem. Special computer software is implemented and illustrative calculation of the traverse shaper's model are performed. Time and frequency plots for chosen generalised coordinates of the model and for several cases of the feedback interaction, are obtained as results.

3

Detector diode circuit noise measurement and power supply method selection for the fiber optic seismograph

75%

Niespodziany S. , Kurzych A. T. , Dudek M.

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tom Vol. 29, No. 2

71--79

EN

This paper investigates the noise levels present at various points in the FOSREM type fiber optic seismograph. The main aim of this research was to discover magnitudes of noise, introduced by various components of the analog and optical circuits of the device. First, the noise present in the electronic circuit without any optics connected is measured. Further experiments show noise levels including the detector diode not illuminated and illuminated. Additional tests were carried out to prove the necessity of analog circuitry shielding. All measurements were repeated using three powering scenarios which investigated the influence of power supply selection on noise. The results show that the electronic components provide a sufficient margin for the use of an even more precise detector diode. The total noise density of the whole device is lower than 4⋅10⁻⁷ rad/(s√Hz). The use of a dedicated Insulating Power Converter as a power supply shows possible advantages, but further experiments should be conducted to provide explicit thermic confirmation of these gains.

4

Cyrkularne modele biznesowe w miastach szwedzkich i holenderskich

63%

Świrk J.

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nr 3

52-60

EN

Contemporary problems related to the poor condition of our natural environment force changes in management models. The model that the economy has followed so far is a linear model - a highly consumption-based model that leads to an increased amount of waste and pollution, and consequently to not taking into account the interests of all stakeholders. As cities struggle with numerous problems (including a constantly growing population, pollution, demand for raw materials, etc.) they should change the way they are managed. The aim of the study is to identify which of them are most often used by these cities. The research questions asked in the article are: what is the role of the city as an authority in these models - is it an implementer or a recipient of circular models solutions? According to the current state of knowledge, is it possible to say that thanks to circular models used in cities the quality of life of residents is improving (from an environmental and social perspective)? The research method used was a review of professional literature (WoS and Scopus databases, as well as full-text databases), internet sources and reports. Three types of circular business models, in which Swedish and Dutch cities participate, were identified. The models that are used predominantly in cities in both Sweden and the Netherlands are models of sharing consumption. Cities as authorities assume different roles - they are both implementers and recipients of the models. It cannot be stated unequivocally that the introduction of circular business models in the current form has a positive effect on the quality of life in a city. Therefore, further research and experiments must be carried out, e.g. in the direction of expanding these models.

PL

Współczesne problemy związane ze złym stanem środowiska naturalnego wymuszają zmiany w modelach gospodarowania. Dotychczasowa gospodarka reprezentowała model liniowy – wysoce konsumpcyjny, prowadzący do wzrostu ilości odpadów i zanieczyszczeń, w konsekwencji do nieuwzględniania dobra wszystkich interesariuszy. Ponieważ miasta borykają się z wieloma problemami (m.in. stale rosnąca liczba ludności, zanieczyszczenia, zapotrzebowanie na surowce itp.), powinny zmienić sposób zarządzania. Celem artykułu jest próba identyfikacji cyrkularnych modeli biznesowych w miastach Szwecji i Holandii oraz wskazanie, które z nich są najczęściej wykorzystywane przez te miasta. Pytania badawcze zadane w artykule brzmią: 1. Jaką rolę odgrywa miasto jako władza w tych modelach (czy jest implementatorem czy odbiorcą rozwiązań modelu cyrkularnego)? 2. Czy zgodnie z obecnym stanem wiedzy można powiedzieć, że dzięki modelom cyrkularnym stosowanym w miastach poprawia się jakość życia mieszkańców (w sensie środowiskowym i społecznym)? Jako metodę badawczą zastosowano przegląd literatury fachowej (bazy WoS i Scopus, a także bazy pełnotekstowe), źródeł internetowych i raportów. Zidentyfikowano trzy rodzaje cyrkularnych modeli biznesowych, w których uczestniczą miasta szwedzkie i holenderskie: model z łańcuchem dostaw o obiegu zamkniętym, model systemu usług i model konsumpcji współdzielonej. W przeważającej mierze wykorzystywane są modele konsumpcji współdzielonej. Miasta jako władza przyjmują różne role – są zarówno implementatorami, jak i odbiorcami rozwiązań tych modeli. Nie można jednoznacznie stwierdzić, że wprowadzenie cyrkularnych modeli biznesowych w obecnej formie wpływa pozytywnie na jakość życia w mieście. Dlatego muszą być prowadzone dalsze badania i eksperymenty np. w kierunku rozbudowywania tychże modeli.

5

Fuzzy logic controller of the ventilation system

51%

Rinkevičiene R. , Kriaučiunas J.

Przegląd Elektrotechniczny

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2012

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tom R. 88, nr 7b

192-194

EN

This paper considers the closed loop model of ventilation system with induction motor drive. The Takagi-Sugeno fuzzy logic controller with PD created. Proposed fuzzy logic controller was created using Matlab and function ANFIS (adaptive neuro-fuzzy inference system).The ventilation system model was simulated with three types of different controllers: conventional PI (proportional-integral), PD (proportional-derivative) and Fuzzy logic PD controller. The advantages of created fuzzy logic controller and simulation results of proposed system were presented and analyzed.

PL

W pracy rozpatrzono model systemu wentylacyjnego ze sprzężeniem zwrotnym wykorzystującego silnik indukcyjny. Dla tego systemu stworzono sterownik PD w oparciu o zasady logiki rozmytej (fuzzy logic). Sterownik zrealizowano w środowisku Matlab-Simulink. Przedstawiono i przeanalizowano metodą symulacyjną podstawowe charakterystyki zaproponowanego sterownika.