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Search results for: ELECTROMAGNETIC (EM) MODELING
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Fast Multi-Objective Antenna Design Through Variable-Fidelity EM Simulations
PublicationA technique for fast multi-objective antenna optimization is introduced. A kriging interpolation surrogate constructed from sampled coarse-mesh EM simulations is utilized by multi-objective evolutionary algorithm (MOEA) to obtain the initial Pareto front approximation. The surrogate is defined in a subset of the original design space, determined by means of independently optimized individual objectives. Response correction techniques...
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Signal propagation in electromagnetic media described by fractional-order models
PublicationIn this paper, signal propagation is analysed in electromagnetic media described by fractional-order (FO) models (FOMs). Maxwell’s equations with FO constitutive relations are introduced in the time domain. Then, their phasor representation is derived for one-dimensional case of the plane wave propagation. With the use of the Fourier transformation, the algorithm for simulation of the non-monochromatic wave propagation is introduced....
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Model of the double-rotor induction motor in terms of electromagnetic differential
PublicationThe paper presents a concept, a construction, a circuit model and experimental results of the double-rotor induction motor. This type of a motor is to be implemented in the concept of the electromagnetic differential. At the same time it should fulfill the function of differential mechanism and the vehicle drive. One of the motor shafts is coupled to the direction changing mechanical transmission. The windings of the external rotor...
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Inverse surrogate modeling for low-cost geometry scaling of microwave and antenna structures
PublicationPurpose–The purpose of this paper is to investigate strategies for expedited dimension scaling ofelectromagnetic (EM)-simulated microwave and antenna structures, exploiting the concept of variable-fidelity inverse surrogate modeling.Design/methodology/approach–A fast inverse surrogate modeling technique is described fordimension scaling of microwave and antenna structures. The model is established using referencedesigns obtained...
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Fast Multi-Objective Antenna Optimization Using Sequential Patching and Variable-Fidelity EM Models
PublicationIn this work, a technique for fast multi-objective design optimization of antenna structures is presented. In our approach, the initial approximation of the Pareto set representing the best possible trade-offs between conflicting design objectives is obtained by means of sequential patching of the design space. The latter is a stencil-based search that aims at creating a path that connects the extreme Pareto-optimal designs (obtained...
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Local-Global Space Mapping for Rapid EM-Driven Design of Compact RF Structures
PublicationIn this work, we introduce a robust and efficient technique for rapid design of compact RF circuits. Our approach exploits two-level space mapping (SM) correction of an equivalent circuit model of the structure under design. The first SM layer (local correction) is utilized to ensure good matching between the equivalent circuit and the electromagnetic model at the component level. On the other hand, the global correction allows...
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A systematic review on cellular responses of Escherichia coli to nonthermal electromagnetic irradiation
PublicationInvestigation of Escherichia coli under electromagnetic fields is of significance in human studies owing to its short doubling time and human‐like DNA mechanisms. The present review aims to systematically evaluate the literature to conclude causality between 0 and 300 GHz electromagnetic fields and biological effects in E. coli. To that end, the OHAT methodology and risk of bias tool were employed. Exponentially growing cells exposed...
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FDTD Method for Electromagnetic Simulations in Media Described by Time-Fractional Constitutive Relations
PublicationIn this paper, the finite-difference time-domain (FDTD) method is derived for electromagnetic simulations in media described by the time-fractional (TF) constitutive relations. TF Maxwell’s equations are derived based on these constitutive relations and the Grünwald–Letnikov definition of a fractional derivative. Then the FDTD algorithm, which includes memory effects and energy dissipation of the considered media, is introduced....
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Zero-Pole Electromagnetic Optimization
PublicationA fast technique for the full-wave optimization of transmission or reflection properties of general linear timeinvariant high-frequency components is proposed. The method is based on the zeros and poles of the rational function representing the scattering parameters of the device being designed and it is the generalization of the technique developed for the design by optimization of microwave filters. The performance of the proposed...
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A mechanistically approached review upon assorted cell lines stimulated by athermal electromagnetic irradiation
PublicationThe probable influence of electromagnetic irradiation on cancer treatment has been deduced from the interaction of artificial electromagnetic emissions with biological organisms. Nonetheless, the suspected health effects induced by electromagnetic-based technology imply that such a treatment may contaminate the adjacent healthy cells. Thus, gaining mechanistic insights into the problem is required to avoid athermal health hazards....
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FPGA-Based System for Electromagnetic Interference Evaluation in Random Modulated DC/DC Converters
PublicationField-Programmable Gate Array (FPGA) provides the possibility to design new “electromagnetic compatibility (EMC) friendly” control techniques for power electronic converters. Such control techniques use pseudo-random modulators (RanM) to control the converter switches. However, some issues connected with the FPGA-based design of RanM, such as matching the range of fixed-point numbers, might be challenging. The modern programming...
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Modeling of Human Tissue for Medical Purposes
PublicationThe paper describes the possibilities offered for medicine by modeling of human tissue using virtual and augmented reality. It also presents three proposals of breast modeling for the use in clinical practice. These proposals are the result of arrangements of medical and computer scientists team (the authors) and will be pursued and implemented in the near future. There is included also a brief description of the most popular methods...
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EM-Driven Multi-Objective Optimization of Antenna Structures in Multi-Dimensional Design Spaces
PublicationFeasible multi-objective optimization of antenna structures is presented. An initial set of Pareto optimal solutions is found using a multi-objective evolutionary algorithm (MOEA) working with a fast surrogate antenna model obtained by kriging interpolation of coarse-discretization EM simulation data. To make the surrogate construction computationally feasible in multi-dimensional design space, the space subset containing non-dominated...
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Expedited EM-driven multi-objective antenna design in highly-dimensional parameter spaces
PublicationA technique for low-cost multi-objective optimization of antennas in highly-dimensional parameter spaces is presented. The optimization procedure is expedited by exploiting fast surrogate models, including coarse-discretization EM antenna simulations and response surface approximations (RSA). The latter is utilized to yield an initial set of Pareto non-dominated designs which are further refined using response correction methods....
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Fundamentals of Data-Driven Surrogate Modeling
PublicationThe primary topic of the book is surrogate modeling and surrogate-based design of high-frequency structures. The purpose of the first two chapters is to provide the reader with an overview of the two most important classes of modeling methods, data-driven (or approx-imation), as well as physics-based ones. These are covered in Chap-ters 1 and 2, respectively. The remaining parts of the book give an exposition of the specific aspects...
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Smart Modeling of Maritime Vessels
PublicationCurrently, the market offers many visualization tools available to graphic designers, engineers, managers and academics working on maritime environments. The practice of visualization involves making and manipulating images that convey novel phenomena and ideas. Visual communication, together with virtual reality environments, is an emerging and rapidly evolving discipline. It brings great advantage over written word or voice alone,...
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Design space reduction and variable-fidelity EM simulations for feasible Pareto optimization of antennas
PublicationA computationally efficient procedure for multi-objective optimization of antenna structures is presented. In our approach, a response surface approximation (RSA) model created from sampled coarse-discretization EM antenna simulations is utilized to yield an initial set of Pareto-optimal designs using a multi-objective evolutionary algorithm. The final Pareto front representation for the high-fidelity model is obtained using surrogate-based...
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Quality of Raspberry Fruit (<em>Rubus idaeus</em> L.) Cultivated under Balanced Fertilization Conditions: Commodity Evaluation
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Signal Propagation in Electromagnetic Media Modelled by the Two-Sided Fractional Derivative
PublicationIn this paper, wave propagation is considered in a medium described by a fractional-order model, which is formulated with the use of the two-sided fractional derivative of Ortigueira and Machado. Although the relation of the derivative to causality is clearly specified in its definition, there is no obvious relation between causality of the derivative and causality of the transfer function induced by this derivative. Hence, causality...
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Multilevel model order reduction with generalized compression of boundaries for 3-d FEM electromagnetic analysis
PublicationThis paper presents a multilevel Model Order Reduction technique for a 3-D electromagnetic Finite Element Method analysis. The reduction process is carried out in a hierarchical way and involves several steps which are repeated at each level. This approach brings about versatility and allows one to efficiently analyze complex electromagnetic structures. In the proposed multilevel reduction the entire computational domain is covered...
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Performance‐driven modeling of compact couplers in restricted domains
PublicationFast surrogate models can play an important role in reducing the cost of EM-driven design closure of miniaturized microwave components. Unfortunately, construction of such models is challenging due to curse of dimensionality and wide range of geometry parameters that need to be included in order to make it practically useful. In this letter, a novel approach to design-oriented modeling of compact couplers is presented. Our method...
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Multimodal Genetic Algorithm with Phase Analysis to Solve Complex Equations of Electromagnetic Analysis
PublicationIn this contribution, a new genetic-algorithm-based method of finding roots and poles of a complex function of a complex variable is presented. The algorithm employs the phase analysis of the function to explore the complex plane with the use of the genetic algorithm. Hence, the candidate regions of root and pole occurrences are selected and verified with the use of discrete Cauchy's argument principle. The algorithm is evaluated...
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Electromagnetic metasurfaces and reconfigurable metasurfaces: a review
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Performance and operation of the CMS electromagnetic calorimeter
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Analysis of the usage possibility of the electromagnetic curtain
PublicationIn the article the definition of IED has been presented as well as its classification and countering methods. The concept of AEGIS device for neutralization of RCIED has been presented. The usage possibility of AEGIS device in civilian environments has been analy sed
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Improvement of impulse radio electromagnetic compatibility
PublicationPublikacja zawiera opis jednej z możliwych technik modyfikacji widma sygnału ultraszerokopasmowego radia impulsowego na przykładzie standardu IEEE 802.15.4a, opartą o zmianę struktury sekwencji generowanych impulsów o bardzo krótkim czasie trwania. Technika ta może zmniejszyć ryzyko wzajemnych zakłóceń pomiędzy nowymi urządzeniami ultraszerkopasmowymi a istniejącymi urządzeniami radiokomunikacji wąskopasmowej
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The method of detection of electromagnetic fields in ground
PublicationW prezentowanej metodzie, detekcja pola polega na pomiarach i analizie zmian rozkładu potencjału. Różnice potencjałów są mierzone jako napięcie pomiędzy elektrodami umieszczonymi w różnych pozycjach na powierzchni ziemi. Analiza tych napięć przy pomocy krótkoczasowej transformaty Fouriera STFT umożliwia wyznaczenie zmian spektralnej gęstości mocy sygnału w funkcji czasu. Ten rodzaj łącznej analizy czasowo-częstotliwościowej daje...
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Electromagnetic plane wave scattering from a cylindrical object with an arbitrary cross section using a hybrid technique
PublicationA hybrid technique combining finite-element and mode-matching methods for the analysis of scattering problems in open and closed areas is presented. The main idea of the analysis is based on the utilization of the finite-element method to calculate the post impedance matrix and combine it with external excitation. The discrete analysis, which is the most time- and memory-consuming, is limited here only to the close proximity of...
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Grand Challenges on the Theory of Modeling and Simulation
PublicationModeling & Simulation (M&S) is used in many different fields and has made many significant contributions. As a field in its own right, there have been many advances in methodologies and technologies. In 2002 a workshop was held in Dagstuhl, Germany, to reflect on the grand challenges facing M&S. Ten years on, a series of M& S Grand Challenge activities are marking a decade of progress and are providing an opportunity to reflect...
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Fundamentals of Physics-Based Surrogate Modeling
PublicationChapter 1 was focused on data-driven (or approximation-based) modeling methods. The second major class of surrogates are physics-based models outlined in this chapter. Although they are not as popular, their importance is growing because of the challenges related to construction and handling of approximation surrogates for many real-world problems. The high cost of evaluating computational models, nonlinearity of system responses,...
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Sparse autoregressive modeling
PublicationIn the paper the comparison of the popular pitch determination (PD) algorithms for thepurpose of elimination of clicks from archive audio signals using sparse autoregressive (SAR)modeling is presented. The SAR signal representation has been widely used in code-excitedlinear prediction (CELP) systems. The appropriate construction of the SAR model is requiredto guarantee model stability. For this reason the signal representation...
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Reliability Modeling for SPMD and DAC Applications in MERPSYS
PublicationIn this chapter we shall see a method for modeling of reliability of application execution in the MERPSYS system, and the results of reliability simulation of the same SPMD and DAC application which we have previously presented in this book. Unlike energy usage modeling and modeling of execution efficiency we could not compare the reliability model and simulation results to real experiment just because the experiment would last too...
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Fast EM-driven size reduction of antenna structures by means of adjoint sensitivities and trust regions
PublicationIn this letter, a simple yet robust and computationally efficient optimization technique for explicit size reduction of antenna structures is presented. Our approach directly handles the antenna size as the main design objective, while ensuring satisfactory electrical performance by means of suitably defined penalty functions. For the sake of accuracy, the antenna structure is evaluated using high-fidelity EM simulation. In order...
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Modeling BIM Objects From Point Clouds. Examples
PublicationThe article presents several ways to obtain BIM (Building Information Modeling) models from point clouds using standard commands in Revit 2018. In Revit geometric forms are possible to obtain in project, family or conceptual environments. Efficient modeling requires knowledge of methods of creating families and components in these environments and ways to combine them. Modeling methods with system and loadable families are presented,...
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Rapid dimension scaling of triple-band antennas by means of inverse surrogate modeling
PublicationGeometry scaling of antennas, i.e., finding optimum dimensions of the structure for given operating conditions and material parameters is an important yet challenging problem. In this paper, we discuss fast dimension scaling of triple-band antennas with respect to operating frequencies. We adopt the inverse surrogate modeling approach where the surrogate model is a function of the three operating frequencies of the antenna and...
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Adaptive Method for Modeling of Temporal Dependencies between Fields of Vision in Multi-Camera Surveillance Systems
PublicationA method of modeling the time of object transition between given pairs of cameras based on the Gaussian Mixture Model (GMM) is proposed in this article. Temporal dependencies modeling is a part of object re-identification based on the multi-camera experimental framework. The previously utilized Expectation-Maximization (EM) approach, requiring setting the number of mixtures arbitrarily as an input parameter, was extended with the...
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Cost-Efficient EM-Driven Size Reduction of Antenna Structures by Multi-Fidelity Simulation Models
PublicationDesign of antenna systems for emerging application areas such as the Internet of Things (IoT), fifth generation wireless communications (5G), or remote sensing, is a challenging endeavor. In addition to meeting stringent performance specifications concerning electrical and field properties, the structure has to maintain small physical dimensions. The latter normally requires searching for trade-off solutions because miniaturization...
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Expedite EM-driven generation of Pareto-optimal trade-off curves for variable-turn on-chip inductors
PublicationThis work presents a novel approach to computationally efficient Pareto front identification for variable-turn on-chip inductors. The final outcome is a set of solutions that correspond to the best trade-offs between conflicting design objectives. Here, we consider minimising inductor area and, simultaneously, maximising its quality factor, while maintaining a specified inductance value at a given operating frequency. As opposed...
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Lokalizacja rozjazdów w plikach wyników pomiarów uzyskiwanych z drezyny pomiarowej EM-120
PublicationPliki z wynikami pomiarów wykonywanych za pomocą drezyny pomiarowej EM-120 zawierają m.in. informacje o lokalizacji w torze lub jego pobliżu charakterystycznych punktów stałych: mostów, przejazdów kolejowo-drogowych, rozjazdów, semaforów i stacji. Dla oceny postępu degradacji toru w trakcie jego eksploatacji szczególne znaczenie mają informacje o położeniu rozjazdów. W referacie przedstawiono obecnie stosowany sposób wprowadzania...
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AEGIS – Mobile Device for Generating Electromagnetic Curtain for Special Applications and Countering the Threats of RCIED
PublicationIn the article the assumptions, design and realization of the technological demonstrator of a mobile device for generating an electromagnetic curtain (with a cryptonym AEGIS) were presented, both in the area of hardware and software. The device is designed to block the radio communication systems by which it is possible to detonate the Radio Controlled Improvised Explosive Devices (RCIEDs). The preliminary laboratory tests of the...
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Low-cost EM-Simulation-based Multi-objective Design Optimization of Miniaturized Microwave Structures
PublicationIn this work, a simple yet reliable technique for fast multi-objective design optimization of miniaturized microwave structures is discussed. The proposed methodology is based on point-by-point identification of a Pareto-optimal set of designs representing the best possible trade-offs between conflicting objectives such as electrical performance parameters as well as the size of the structure of interest. For the sake of computational...
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Software Modeling from the Perspective of Intuitive Information Processing
PublicationThere is psychological evidence that humans process information not only consciously but also intuitively. Intuitive information processing is present also during the activities related to software modeling. The goal of this paper is to analyze software modeling from the perspective of theories which describe intuitive (nonconscious, implicit) information processing. The paper includes presentation of relevant psychological theories,...
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On the EM algorithm for the estimation of speech AR parameters in noise
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Mechanika ogólna : Rozwiązywanie zagadnień z MATHCAD-em
PublicationW książce zaprezentowano nową metodę studiowania mechaniki, umożliwiającą kształtowanie intuicji inżynierskiej. W tym celu wykorzystano program MATHCAD, który usprawnia żmudne obliczenia i pozwala zaoszczędzić czas na dokładną analizę rozważanych zjawisk oraz otrzymanych wyników. Książka polecana studentom na zajęcia z mechaniki ogólnej oraz jako praktyczną pomoc przy wykonywaniu prac dyplomowych, a także inżynierom szukającym...
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Drgania mechaniczne : Rozwiązywanie zagadnień z MATHCAD-em
PublicationAutor proponuje jednoczesne poznawanie teorii drgań mechanicznych i wdrażanie jej do analizy własności dynamicznych układów mechanicznych. Stosuje do tego celu wspomaganie komputerowe za pomocą programu MATHCAD. Wyjaśnia naturę zjawiska drgań mechanicznych i jego znaczenie w technice oraz wpływ na środowisko. Prezentuje też wzorcowe programy pomocne przy samodzielnym programowaniu obliczeń. Podaje zasady tworzenia modeli dyskretnych...
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Diagonalized Macromodels in Finite Element Method for Fast Electromagnetic Analysis of Waveguide Components
PublicationA new technique of local model-order reduction (MOR) in 3-D finite element method (FEM) for frequency-domain electromagnetic analysis of waveguide components is proposed in this paper. It resolves the problem of increasing solution time of the reduced-order system assembled from macromodels created in the subdomains, into which an analyzed structure is partitioned. This problem becomes particularly relevant for growing size and...
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The use of the electromagnetic field in microbial process bioengineering
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Advanced Electromagnetic Metamaterials for Temperature Sensing Applications
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Time reconstruction and performance of the CMS electromagnetic calorimeter
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Design of electromagnetic shields for small electronic units.
PublicationSystemy elektroniczne, które przetwarzają informacje niejawną lub informację chronioną prawem, wymagają nie tylko jej szyfrowania, ale także zastosowania środków i metod minimalizacji ulotu elektromagnetycznego, jaki zawsze towarzyszy elektronicznemu przetwarzaniu informacji. Wymagania dotyczące tłumienia emisji promieniowanej i przewodzonej, w szczególności dotyczące przetwarzania i przesyłania informacji tajnej osiągają poziom...