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Publikacje z roku 2016
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Simplified, multiregional fuzzy model of a nuclear power plant steam turbine
- Paweł Sokólski
- Tomasz Adam Rutkowski
- Kazimierz Duzinkiewicz
Power systems, including steam turbines and synchronous generators, are complex nonlinear systems with parameters varying over time. The paper presents the developed simplified, multiregional fuzzy model of the steam turbine of a nuclear power plant turbine generator set and compares the results with a full nonlinear model and commonly used linear input-output model of a steam turbine. The proposed model consist of series of linear input-output models defined for specific steam turbine operating points and one fuzzy switching module with Takagi-Sugeno reasoning interface. Provided simulation results indicate that the response of presented simplified fuzzy multiregional steam turbine model is very close to the reference nonlinear steam turbine model such that the maximum absolute error is around few percent for considered operating point changes, 30-100% of nominal mechanical power. Hence steam turbine model in such form may increase the accuracy of developed control algorithms, which use system model for adaptation or prediction purposes.
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Simplified probabilistic analysis of settlement of cyclically loaded soil stratum using point estimate method
- Jarosław Przewłócki
- Jarosław Górski
- Waldemar Świdziński
The paper deals with the probabilistic analysis of settlement of a non-cohesive soil layer subjected to cyclic loading. Originally, the settlement assessment is based on deterministic compaction model which requires integration of a set of differential equations. However, making use of the Bessel functions the settlement of the soil stratum can be calculated by means of simplified algorithm. The compaction model parameters were determined for the soil samples taken from the subsoil near Izmit Bay, Turkey. The computations were performed for various sets of random variables. The point estimate method was applied and the results were verified using the Monte Carlo method.
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Simplified saturation modelling in three-leg power transformer for the system stability analisys
- Filip Kutt
- Michał Michna
- Robert Małkowski
- Maciej Łosiński
The paper presents a simplified method for modelling non-linearity of the magnetic circuit of the power transformer. The saturation effect is implemented by describing the self and mutual inductances as a function of the magnetic flux. The most important element of this function is the saturation coefficient which is calculated based on transient state during the unloaded transformer switch on. The transformer model is described using the MAST hardware description language in Synopsys Saber simulator. Table Look-Up tool is used to define the saturation coefficient in function of the flux magnitude in per units. The simulation and measurements results were compared in order to verify modelling method
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Simplified stability analysis of steel cylindrical silos with corrugated walls and vertical columns
- Karol Rejowski
- Piotr Iwicki
In the paper a simplified stability analysis of steel cylindrical silos composed of corru¬gated walls and vertical open-sectional columns was proposed. The whole 3D silo was modeled as a single column resting on elastic foundation provided by the silo walls. In proposed formula for the calculation of the foundation stiffness the curvature of the silo walls was taken into account. Three different analyses were carried out using commercial FE package ABAQUS: linear buckling, dynamic with the geometric non-linearity and dynamic with the both geometric and material non-linearity. Axisymmetric and non axisymmetric loads imposed by a bulk solid following Eurocode 1 were considered. The calculated buck¬ling loads were compared with the permissible one given by Eurocode 3 and with results found for the whole silo modeled by shell elements.
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Simulation Model of IMS/NGN with Transport Stratum Based on MPLS Technology
- Sylwester Kaczmarek
- Łukasz Łuczaj
- Maciej Sac
In the paper we continue our research on traffic modelling in the Next Generation Network (NGN) architecture, which includes the IP Multimedia Subsystem (IMS) elements. A simulation model of a single NGN domain with transport stratum based on the Multiprotocol Label Switching (MPLS) technology is proposed, which allows evaluation of mean response time of this stratum. The simulation model is applied to verify the results obtained using the previously proposed analytical model.
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Simulation-driven design of compact ultra-wideband antenna structures
- Sławomir Kozieł
- Adrian Bekasiewicz
Purpose–The purpose of this paper is to investigate strategies and algorithms for expedited designoptimization and explicit size reduction of compact ultra-wideband (UWB) antennas.Design/methodology/approach–Formulation of the compact antenna design problem aiming atexplicit size reduction while maintaining acceptable electrical performance is presented. Algorithmicframeworks are described suitable for handling various design situations and involving simulationmodels without and with response gradients available. Numerical and experimental case studies areprovided demonstrating feasibility of solving real-world miniaturized antenna design tasks.Findings–It is possible, through appropriate combination of the global and local optimizationmethods, surrogate modeling techniques and response correction methods, to find optimumdimensions of antenna structures that minimize antenna size while maintaining acceptable electricalperformance. Design optimization can be performed at practically feasible computational costs.Research limitations/implications–The study summarizes recent advances in miniaturization-oriented design optimization of UWB antennas. The presented techniques reach far beyond thecommonly used design approaches based on parameter sweeps and similar hands-on methods,particularly in terms of automation, reliability, and reduction of the computational costs of thedesign processes.Originality/value–The proposed design problem formulation and algorithmic frameworks proveduseful for rapid design of compact UWB antenna structures, which is extremely challenging whenusing conventional methods. To the knowledge, this is the first attempt to efficient solving of this typeof design problems, especially in the context of explicit antenna size reduction.
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Single-Anchor Indoor Localization Using ESPAR Antenna
- Mateusz Rzymowski
- Przemysław Woźnica
- Łukasz Kulas
In this paper a new single-anchor indoor localization concept employing Electronically Steerable Parasitic Array Radiator (ESPAR) antenna has been proposed. The new concept uses a simple fingerprinting algorithm adopted to work with directional main beam and narrow minimum radiation patterns of ESPAR antenna that scans 360° area around the base station, while the signal strength received from a mobile terminal is being recorded for each configuration. The paper describes the antenna design, necessary fingerprinting algorithm expansion and shows measurements of the proof-of-concept prototype performed within the experimental set-up. Localization results obtained from indoor measurements indicate that the proposed concept can provide better results than the similar approach based on a switched beam antenna introduced in.
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Single-phase product obtained via crude glycerine depolymerisation of polyurethane elastomer: structure characterisation and rheological behaviour
- Patrycja Jutrzenka Trzebiatowska
- Janusz Datta
Polyurethane recycling is a topic of growing interest due to the increasing amount of polyurethanewaste. The main purpose of polyurethane feedstock recycling is to recover the starting polyol, a valuable material. In thiswork, amethod of polyurethane thermo-chemical recycling, glycerolysisbymeansof crude glycerine, is proposed. Themaineffort is focusedonthe employment of crude glycerine without purification from biodiesel production as a decomposing agent for polyurethane recycling. The influenceofpolyurethane-to-glycerinemass ratio (PU/GL)onchemical structurewas examined using Fourier transforminfrared (FTIR) and 1H NMR spectroscopies and gel permeation chromatography (GPC). Glass transition temperature (Tg) and thermal properties using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and also rheology were analysed. FTIR and 1HNMRanalyses of the glycerolysates showed peaks similar to those of virgin polyol. FromGPC chromatogramsitwas concluded thatglycerolysates are amixture of compoundswith different molecularweights, such as recoveredpolyol, urethane oligomers or carbamates. Glycerolysates indicated Tg in the range from −65 to −60 ∘C and, for high PU/GL ratio, a second Tg appeared. Thermal stability of glycerolysates increased with increasing PU/GL ratio. The molecular weight of glycerolysates ranged from 700 to 1020gmol−1 depending on PU/GL mass ratio. The semi-products were defined as non-Newtonian fluids, where viscosity depended on the shear rate. Crude glycerine, derived from biodiesel production, was successfully used in polyurethane decomposition, resulting in valuable semi-products.
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Situational Awareness Network for the Electric Power System: the Architecture and Testing Metrics
- Damiano Bolzoni
- Rafał Leszczyna
- Michał Wróbel
The contemporary electric power system is highly dependent on Information and Communication Technologies which results in its exposure to new types of threats, such as Advanced Persistent Threats (APT) or Distributed-Denial-of-Service (DDoS) attacks. The most exposed components are Industrial Control Systems in substations and Distributed Control Systems in power plants. Therefore, it is necessary to ensure the cyber security of this critical infrastructure and develop new cyber security technologies able to protect from advanced cyber threats. In this paper a pioneering Situation Awareness Network for the electric power system is presented together with a set of metrics for its testing..
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Size and mass minimization of capacitor bank in a power converter DC line of DC drive with closed loop control system with PWM and current limitation
- Pavel Borisov
- Nikolai Poliakov
- Ryszard Strzelecki
Paper deals with evaluation equations for power filter of AC-DC power converter which allows to provide size and mass minimization of capacitor bank in DC drive closed loop systems with PWM and current limitation. Reliability of provided equations is proved by simulation in MATLAB/Simulink
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Size-Reduction-Oriented Design of Compact CPW-Fed UWB Monopole Antenna
- Sławomir Kozieł
- Adrian Bekasiewicz
A structure and design optimization of compact CPW-fed UWB monopole antenna is presented. Explicit size reduction through constrained numerical optimization of all relevant geometry parameters of the structure leads to a very small footprint of only 321 mm2. At the same time, a very wide antenna bandwidth is achieved from 3.1 GHz to 17 GHz.
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SKANING LASEROWY JAKO TECHNOLOGIA WIELU ZASTOSOWAŃ - POMIARY GEODEZYJNE NA POTRZEBY ARCHITEKTÓW
- Anna Sobieraj-Żłobińska
- Jakub Szulwic
- Wioleta Błaszczak-bąk
- Ewa Minkowska
Skaning laserowy umożliwia pozyskanie chmury punktów, która może być opracowana i wykorzystana w różnych etapach inwestycji, od wykonywania prostych pomiarów na uzyskanym dzięki chmurze modelu lub na samej chmurze, po opracowywanie modeli cyfrowych zeskanowanych obiektów, ich wizualizacje i aranżacje wnętrz. W pracy przedstawiono możliwości zastosowania wyników naziemnego skanowania laserowego do opracowania projektu aranżacji wnętrza budynku o charakterze biurowym. Wymiarowanie obiektu zostało poprzedzone procesem wykrywania krawędzi i płaszczyzn w pozyskanych chmurach punktów. W ramach współpracy z architektem wykonany został projekt wnętrza.
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Skłonność do tworzenia pęknięć zimnych złączy ze stali ferrytyczno-austenitycznej typu dupleks 2205 przy spawaniu pod wodą metodą mokrą
- Karolina Prokop-Strzelczyńska
- Grzegorz Rogalski
Spawanie pod wodą stali ferrytyczno-austenitycznych typu dupleks budzi coraz szersze zainteresowanie. Wynika to z pilnej potrzeby opracowania spawalniczych technologii naprawczych rurociągów do transportu ropy naftowej eksploatowanych pod wodą. Do badań wykorzystano metodę mokrą przy zastosowaniu spawania elektrodami otulonymi (proces 111). Wykonano technologiczne próby Tekken pod wodą na głębokości 0,5 m oraz na powietrzu. Przeprowadzono badania metalograficzne makroskopowe i mikroskopowe, pomiary zawartości ferrytu oraz pomiary twardości złączy. Uzyskane wyniki badań wykazały, że spawanie stali dupleks pod wodą może prowadzić do formowania się pęknięć zimnych. W rozpatrywanym przypadku związane jest to z niestabilnością jarzenia się łuku.
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Skutki starzenia się społeczeństwa dla rynku pracy w Polsce - wybrane aspekty
- Marta Maier
Na przełomie XX i XXI wieku zjawisko starzenia się ludności postrzegane jest jako dominujący proces demograficzny, który odzwierciedla się w zmianie struktury wieku ludności i wzroście liczby osób starszych w ogólnej populacji. Rynek pracy stoi zatem przed koniecznością wprowadzenia głębokich reform o charakterze społeczno-gospodarczym umożliwiających dostosowanie do nowego otoczenia demograficznego. Polityka państwa musi odnaleźć drogę optymalnego rozwoju dla starzejącego się społeczeństwa w obliczu zmieniającej się struktury ludności. Celem artykułu jest przedstawienie konsekwencji procesu starzenia się społeczeństwa na rynek pracy w Polsce. Można zatem postawić tezę, że ma to wpływ na rynek pracy zarówno z punktu widzenia popytu (zwiększające się zapotrzebowanie na zawody wspierające seniorów w codziennym funkcjonowaniu) oraz podaży (kurczące się zasoby pracy). W artykule wykorzystano dane Głównego Urzędu Statystycznego odnoszące się do sytuacji demograficznej w Polsce.
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Sliding burnishing technology of holes in hardened steel
- Włodzimierz Przybylski
New technology with sliding burnishing of holes with cylindrical surface, made of hardened steel /60 HRC/, is presented in the paper.After burnishing operation on hole diameter 30 mm in satellite gear wheel the surface roughness parameter Ra=0,02-0,04 micrometers was obtained. The method and results of research as technological conclusion are presented.
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Sludge Treatment Reed Beds (STRBs) as a Eco-solution of Sludge Utilization for Local Wastewater Treatment Plants
- Katarzyna Kołecka
- Hanna Obarska-Pempkowiak
- Magdalena Gajewska
Sewage sludge is a by-product of wastewater treatment processes. In Poland, the amout of sewage sludge has been still growing in recent years, due to inhencement of pollutants removal in wastewater treatment plants (WWTPs). One of the systems used to transform sewage sludge into fertilizer is a technology called Sludge Treatment Reed Beds (STRBs). Reed systems are periodically irrigated with sewage sludge with a low dry matter content (from 0.5 to 1.5 % DM). The accumulation time of sludge necessary to achieve stabilization is approximately 10–15 years. Sludge is transformed into humus substances. After checking the microbiological and physico-chemical properties stabilized sludge can be used for agricultural purposes. In the recent years, Denmark, France and Germany have applied integrated technologies of dewatering and stabilization of sewage sludge in these systems. The aim of the study is to present: (i) general principles for the construction and for the design of reed systems for integrated dewatering and stabilization of sewage sludge, (ii) conditions of proper operation of the systems (iii) the economic and environmental aspects of using reed technology based on the literature and our own research. Conducted research confi rmed that sewage sludge dewatered and stabilized in STRBs can be used as fertilizer in agriculture.
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Small-Angle Neutron Scattering Study of the Structure of Mixed Micellar Solutions Based on Heptaethylene Glycol Monotetradecyl Ether and Cesium Dodecyl Sulfate
- Aldona Rajewska
- Krystyna Mędrzycka
- Elżbieta Hallmann
- D.v. Soloviov
The micellization in mixed aqueous systems based on a nonionic surfactant, heptaethylene glycol monotetradecyl ether (C14E7), and an anionic surfactant, cesium dodecyl sulfate, has been investigated by small-angle neutron scattering. Preliminary data on the behavior of the C14E7 aqueous solutions (with three concentrations, 0.17, 0.5, and 1%) mixed with a small amount of anionic surfactant, cesium dodecyl sulfate, are reported.
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Smart Cities System Design Method Based on Case Based Reasoning
- Cezary Orłowski
- Artur Ziółkowski
- Aleksander Orłowski
- Paweł Kapłański
- Tomasz Sitek
- Witold Pokrzywnicki
The objective of this paper is to present the results of research carried out to develop a design method for Smart Cities systems. The method is based on the analysis of design cases of Smart Cities systems in cities, the selection of the city appropriate to the requirements for implementation and application. The Case Based Reasoning method was used to develop the proposed design methodology, along with mechanisms of the conversion of project processes and roles to Rational Unified Processes (RUP). The prerequisite for the proposed method is that the enterprise manager must be knowledgeable about high-level Smart Cities system architecture and the design framework applied. The authors, being themselves knowledgeable about architecture of this kind and about project environments which implement KPI models, propose a generic solution applicable to any environments and system architectures.
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Smart Innovation Management in Product Life Cycle
- Mohammad Waris
- Cesar Sanin
- Edward Szczerbicki
The present paper proposes a framework for smart innovation management of the product using a Smart Knowledge Management System comprising Set of Experience Knowledge Structure (SOEKS) and Decisional DNA. This proposed system will allow the entrepreneurs and organizations to perform the innovation process technically and quickly as this framework will store knowledge as well as experiences of the past innovations done in various products. It will also consider the possibility of introducing the new technology into the product. In short it will act as the expert innovator capable of doing the innovation technically utilizing the past experiences and several possible options based on the priorities of the user.
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Smart sustainable cities : Reconnaissance Study
- Elsa Estevez
- Nuno Lopes
- Tomasz Janowski
The global urban population is expected to grow by 63 percent between 2014 and 2050 – compared to an overall global population growth of 32 percent during the same period. Megacities with over 20-million inhabitants will see the fastest increase in population – and at least 13 new megacities are expected by 2030, in addition to the 28 existing today. The fastest growing urban centres contain around one-million inhabitants, and are located in lower-middle-income countries in Asia and Africa. The anticipated growth of cities creates unprecedented sustainability challenges. Increasing demands for energy, water, sanitation, education, healthcare, housing, transport, and public services are testing the limits of city infrastructure. Smart Cities have emerged as a response to the challenges and opportunities created by rapid urbanization. Smart Cities deploy intelligent urban systems to serve socio-economic and ecological development, improve quality of life, and address the origins of social instability in cities. This report, produced by the United Nations University’s Operating Unit on Policy-Driven Electronic Governance, and funded by IDRC, examines how Smart Cities can advance sustainability in different development situations.