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Wyniki wyszukiwania dla: SIMULATION OF SHIP PROPULSION SYSTEM
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Low-Cost Modeling of Microwave Components by Means of Two-Stage Inverse/Forward Surrogates and Domain Confinement
PublikacjaFull-wave electromagnetic (EM) analysis is one of the most important tools in the design of modern microwave components and systems. EM simulation permits reliable evaluation of circuits at the presence of cross-coupling effects or substrate anisotropy, as well as for accounting for interactions with the immediate environment. However, repetitive analyses required by EM-driven procedures, such as parametric optimization or statistical...
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Safety assessment of a concrete viaduct damaged by vehicle impact and an evaluation of the repair
PublikacjaDamage to lower parts of viaducts caused by impact from under-passing high vehicles is relatively frequent. One such incident, in which a viaduct was damaged by the impact from a truck with an improperly assembled hydraulic crane, is considered in this work. The analysis is based on a detailed object damage evaluation, 3D laser scanning, and numerical simulations. The aim of the study is to accurately model the vehicle impact into...
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IP Core of Coprocessor for Multiple-Precision-Arithmetic Computations
PublikacjaIn this paper, we present an IP core of coprocessor supporting computations requiring integer multiple-precision arithmetic (MPA). Whilst standard 32/64-bit arithmetic is sufficient to solve many computing problems, there are still applications that require higher numerical precision. Hence, the purpose of the developed coprocessor is to support and offload central processing unit (CPU) in such computations. The developed digital...
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Simulating propagation of coherent light in random media using the Fredholm type integral equation
PublikacjaStudying propagation of light in random scattering materials is important for both basic and applied research. Such studies often require usage of numerical method for simulating behavior of light beams in random media. However, if such simulations require consideration of coherence properties of light, they may become a complex numerical problems. There are well established methods for simulating multiple scattering of light (e.g....
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Improved Modeling of Microwave Structures Using Performance-Driven Fully-Connected Regression Surrogate
PublikacjaFast replacement models (or surrogates) have been widely applied in the recent years to accelerate simulation-driven design procedures in microwave engineering. The fundamental reason is a considerable—and often prohibitive—CPU cost of massive full-wave electromagnetic (EM) analyses related to solving common tasks such as parametric optimization or uncertainty quantification. The most popular class of surrogates are data-driven...
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Wieloobszarowa regulacja systemu turbogeneratora elektrowni jądrowej =Multiregional control of nuclear power plant turbogenerator system
PublikacjaW artykule przedstawiono propozycję zaawansowanej struktury sterowania układem turbogeneratora w szerokim zakresie zmian zapotrzebowania na moc czynną. Dla potrzeb syntezy tej struktury wykorzystano nieliniowe, dynamiczne modele turbiny parowej i generatora synchronicznego współpracującego z systemem elektroenergetycznym. Zaproponowane algorytmy sterowania oparte są odpowiednio o wieloobszarowe regulatory rozmyte, z lokalnymi regulatorami...
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Modelowanie matematyczne górnej sieci trakcyjnej dla potrzeb diagnostyki odbieraków prądu
PublikacjaGórna sieć trakcyjna jest obecnie najbardziej skutecznym sposobem zasilania kolejowych pojazdów elektrycznych. Wzrost prędkości pojazdów zwiększa pobór mocy i wymaga zapewnienia właściwej współpracy odbieraków prądu pojazdów z siecią jezdną. Metody modelowania i projektowania wspomaganego komputerowo dla górnej sieci trakcyjnej są obecnie na całym świecie szeroko rozwijane. W artykule przedstawiono nowy model matematyczny elementów...
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On Decision-Making Strategies for Improved-Reliability Size Reduction of Microwave Passives: Intermittent Correction of Equality Constraints and Adaptive Handling of Inequality Constraints
PublikacjaDesign optimization of passive microwave components is an intricate process, especially if the primary objective is a reduction of the physical size of the structure. The latter has become an important design consideration for a growing number of modern applications (mobile communications, wearable/implantable devices, internet of things), where miniaturization is imperative due to a limited space allocated for the electronic circuitry....
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Electrochemical simulation of metabolism for antitumor-active imidazoacridinone C-1311 and in silico prediction of drug metabolic reactions
PublikacjaThe metabolism of antitumor-active 5-diethylaminoethylamino-8-hydroxyimidazoacridinone (C-1311) has been investigated widely over the last decade but some aspects of molecular mechanisms of its metabolic transformation are still not explained. In the current work, we have reported a direct and rapid analytical tool for better prediction of C-1311 metabolism which is based on electrochemistry (EC) coupled on-line with electrospray...
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Interworking and Cross-layer Service Discovery Extensions for IEEEE802.11s Wireless Mesh Standard
PublikacjaWith the rapid popularization of mobile end-user electronic devices wireless network technologies begin to play a crucial role as networks access technologies. While classic point-to-multipoint wireless access systems, based on fixed infrastructure of base stations providing access to clients, remain the main most popular solution, an increasing attention is devoted to wireless mesh systems, where each connecting client can extend...
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Service and Path Discovery Extensions for Self-forming IEEE 802.11s Wireless Mesh Systems
PublikacjaWith the rapid growth of the quantity and capabilities of end-user electronic devices, both stationary and mobile, they are employed in increasing number of applications. In this situation, wireless network technologies begin to play a crucial role as networks access technologies, as cable-based solutions tend to be of limited utility in case of easily portable or mobile devices. Resulting development of wireless technologies reached...
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Spatial aspects of urban air quality management: Estimating the impact of micro-scale urban form on pollution dispersion
PublikacjaUrban planning and design solutions affect urban ventilation conditions, thus mitigating the effects of atmospheric pollution. However, these findings are not being implemented in the planning practice to a sufficient extent, partly due to the lack of specific guidelines. Moreover, many urban air quality monitoring (AQM) sites have low represnentativeness and thus do not provide comprehensive data for effective urban air pollution control...
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Optimization-Based Robustness Enhancement of Compact Microwave Component Designs with Response Feature Regression Surrogates
PublikacjaThe ability to evaluate the effects of fabrication tolerances and other types of uncertainties is a critical part of microwave design process. Improving the immunity of the device to parameter deviations is equally important, especially when the performance specifications are stringent and can barely be met even assuming a perfect manufacturing process. In the case of modern miniaturized microwave components of complex topologies,...
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Performance-Driven Surrogate Modeling of High-Frequency Structures
PublikacjaThe development of modern high-frequency structures, including microwave and antenna components, heavily relies on full-wave electromagnetic (EM) simulation models. Notwithstanding, EM-driven design entails considerable computational expenses. This is especially troublesome when solving tasks that require massive EM analyzes, parametric optimization and uncertainty quantification be-ing representative examples. The employment of...
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Wybrane metody diagnostyki łożysk silników indukcyjnych oparte o pomiar prądu
PublikacjaW artykule zawarto przegląd wybranych metod diagnostyki łożysk silnika indukcyjnego, bazujących na pomiarach prądu zasilającego. Jedno z nowych rozwiązań przetwarzania sygnałów zostało zaadaptowane przez autorów do stosowanego przez nich systemu diagnostycznego. Wyniki wstępnych badań symulacyjnych zweryfikowanych badaniami na rzeczywistym obiekcie wskazują, że rozwiązanie to ułatwia diagnozowanie. Autorzy zamierzają prowadzić...
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Metoda diagnostyki cieplno-przepływowej turbin parowych wykorzystująca elementy algorytmów genetycznych
PublikacjaRozprawa doktorska poświęcona jest opisowi budowania metody diagnostyki cieplno-przepływowej z wykorzystaniem elementów algorytmów genetycznych. Do tworzenia założeń i algorytmów metody posłużono się przykładem funkcjonowania bloku elektrowni kondensacyjnej ze szczególnym uwzględnieniem układu łopatkowego turbiny parowej. Celem pracy jest zbudowanie metody diagnostyki cieplno-przepływowej. Zadaniem metody jest przeprowadzenie procesu...
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Przykłady realizacji i interpretacji wyników sondażowych pomiarów terenowych w czynnych systemach wodociągowych
PublikacjaW pracy przedstawiono przebieg realizacji i rezultaty sondażowych pomiarów terenowych w trzech układach dystrybucji wody o zróżnicowanym przewymiarowaniu sieci wodociągowej. Pomiary przeprowadzono w dążeniu do identyfikacji właściwości (cech) strukturalnych i funkcjonalnych układów po wieloletniej ich eksploatacji. Ustalenia te determinują opracowanie programu realizacji pomiarów dla potrzeb tarowania komputerowego modelu przepływu...
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Przykłady realizacji i interpretacji wyników sondażowych pomiarów terenowych w czynnych systemach dystrybucji wody
PublikacjaW pracy przedstawiono przebieg realizacji i rezultaty sondażowych pomiarów terenowych w trzech układach dystrybucji wody o zróżnicowanym przewymiarowaniu sieci wodociągowej. Pomiary przeprowadzono w dążeniu do identyfikacji właściwości (cech) strukturalnych i funkcjonalnych układów po wieloletniej ich eksploatacji. Ustalenia te determinują opracowanie programu realizacji pomiarów dla potrzeb tarowania komputerowego modelu przepływu...
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Cost-Efficient Globalized Parameter Optimization of Microwave Components through Response-Feature Surrogates and Nature-Inspired Metaheuristics
PublikacjaDesign of contemporary microwave devices predominantly utilizes computational models, including both circuit simulators, and full-wave electromagnetic (EM) evaluation. The latter constitutes the sole generic way of rendering accurate assessment of the system outputs that considers phenomena such as cross-coupling or radiation and dielectric losses. Consequently, for reliability reasons, the final tuning of microwave device parameters...
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Low-Cost Quasi-Global Optimization of Expensive Electromagnetic Simulation Models by Inverse Surrogates and Response Features
PublikacjaConceptual design of contemporary high-frequency structures is typically followed by a careful tuning of their parameters, predominantly the geometry ones. The process aims at improving the relevant performance figures, and may be quite expensive. The reason is that conventional design methods, e.g., based on analytical or equivalent network models, often only yield rough initial designs. This is especially the case for miniaturized...
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CO2 capture through direct-contact condensation in a spray ejector condenser and T- junction separator
PublikacjaThe design principle underlying the steam condensation and CO2 purification in a gas power plant with a focus on reducing CO2 emissions encompasses the deployment of a spray ejector condenser (SEC) and separator. This innovative system facilitates direct-contact condensation of steam with non-condensable gas (CO2) by inter acting with a spray of subcooled water, seamlessly integrated with a T-junction separator mechanism aimed...
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Influence of external walls' thermal capacitance on indoor thermal comfort
PublikacjaThe doctoral thesis presents the results of numerical investigations on the influence of walls’ thermal capacitance on indoor thermal comfort. A proper set of thermal parameters of a building structure can considerably limit the heating / cooling demand, and passively increase the indoor thermal comfort. However the effect of building thermal capacitance on indoor conditions is complex and not always beneficial. Among a great number...
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Numerical Issues and Approximated Models for the Diagnosis of Transmission Pipelines
PublikacjaThe chapter concerns numerical issues encountered when the pipeline flow process is modeled as a discrete-time state-space model. In particular, issues related to computational complexity and computability are discussed, i.e., simulation feasibility which is connected to the notions of singularity and stability of the model. These properties are critical if a diagnostic system is based on a discrete mathematical model of the flow...
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The hydrogen bond network structure within the hydration shell around simple osmolytes: Urea, tetramethylurea, and trimethylamine-N-oxide, investigated using both a fixed charge and a polarizable water model
PublikacjaDespite numerous experimental and computer simulation studies, a controversy still exists regarding the effect of osmolytes on the structure of surrounding water. There is a question, to what extent some of the contradictory results may arise from differences in potential models used to simulate the system or parameters employed to describe physical properties of the mixture and interpretation of the results. Bearing this in mind,...
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The hydrogen bond network structure within the hydration shell around simple osmolytes: Urea, tetramethylurea, and trimethylamine-N-oxide, investigated using both a fixed charge and a polarizable water model
PublikacjaDespite numerous experimental and computer simulation studies, a controversy still exists regarding the effect of osmolytes on the structure of surrounding water. There is a question, to what extent some of the contradictory results may arise from differences in potential models used to simulate the system or parameters employed to describe physical properties of the mixture and interpretation of the results. Bearing this in mind,...
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Energy consumption optimization in wastewater treatment plants: Machine learning for monitoring incineration of sewage sludge
PublikacjaBiomass management in terms of energy consumption optimization has become a recent challenge for developed countries. Nevertheless, the multiplicity of materials and operating parameters controlling energy consumption in wastewater treatment plants necessitates the need for sophisticated well-organized disciplines in order to minimize energy consumption and dissipation. Sewage sludge (SS) disposal management is the key stage of...
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On the influence of shell element properties on the response of car model in crash test
PublikacjaIt goes without saying that numerical simulations play important role in the modern engineering practice. Contemporary CAD environments combined with FEM solvers, along with computer power of modern processors, give the engineer fast and efficient tool. Ultimately, however it is the user alone who is responsible for the correctness of the results. As long as the FEM calculations remain in the sphere of academic exercise, the inevitable...
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Using LSTM networks to predict engine condition on large scale data processing framework
PublikacjaAs the Internet of Things technology is developing rapidly, companies have an ability to observe the health of engine components and constructed systems through collecting signals from sensors. According to output of IoT sensors, companies can build systems to predict the conditions of components. Practically the components are required to be maintained or replaced before the end of life in performing their assigned task. Predicting...
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A system for Direction-Of-Arrival estimation in ISM 2.4 GHz frequency band based on ESPAR antenna and SDR technology
PublikacjaDetermination of the direction of the signal arrival (DOA) finds many applications in various areas of science and industry. Knowledge of DOA is used, among others to determine the position of a satellite with a low Earth orbit (LEO), localization of people and things as well as in research of wireless communication systems, for instance the determination of the number of...
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Zintegrowane sterowanie systemami zaopatrzenia w wodę pitną
PublikacjaOptymalne ekonomicznie zaspokojenie w miastach bieżącego zapotrzebowania na wodę pitną tak, aby spełnione były wymagania jakości dostaw oraz jakości samej wody jest złożonym zadaniem. Zarówno aspekty aplikacyjne jak i teoretyczne tego problemu są przedmiotem intensywnych prac prowadzanych w sektorach naukowych i przemysłowych na całym świecie. Prace te finansowane są przez przemysł, komitety naukowe oraz Programy Ramowe Unii Europejskiej....
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The hybrid estimation algorithm for wastewater treatment plant robust model predictive control purposes at medium time scale
PublikacjaThe paper proposes an approach to designing the hybrid estimation algorithm/module (HEA) with moving measurements window for Wastewater Treatment Plant (WWTP) Robust Model Predictive Control (RMPC) purposes at medium time scale. The RMPC uses a dedicated grey-box model of biological reactor for the system outputs prediction purposes. The grey-box model parameters are dependant on the plant operating point. Hence, these parameters...