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Design centering of compact microwave components using response features and trust regions
PublicationFabrication tolerances, as well as uncertainties of other kinds, e.g., concerning material parameters or operating conditions, are detrimental to the performance of microwave circuits. Mitigating their impact requires accounting for possible parameter deviations already at the design stage. This involves optimization of appropriately defined statistical figures of merit such as yield. Alt-hough important, robust (or tolerance-aware)...
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Modelowanie przepływu ustalonego niejednostajnego w sieciach kanałów otwartych z uwzględnieniem obiektów hydrotechnicznych
PublicationW pracy sformułowano zagadnienie brzegowe dla równania energii opisującego przepływ ustalony niejednostajny i przedstawiono sposób jego rozwiązania przy pomocy metody różnicowej. Zaproponowana metoda obliczeń nadaje się do analizy przepływu w dendrycznych i pierścieniowych sieciach kanałów otwartych. Ponadto na przykładzie przelewu prostokątnego zaproponowano metodę uwzględnienia w obliczeniach zabudowy hydrotechnicznej. Słowa...
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Green Sample Collection
PublicationThe term of “green sample collection” is directly associated with both passive and dynamic analytical tools which allow for simultaneous management of the stage of collection and isolation and/or enrichment of a broad spectrum of chemical compounds from environmental samples. The use of passive sampling techniques at the stage of sample collection makes it possible to obtain in a simple yet inexpensive manner an analytical information...
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Application of Shape Memory Alloys in Retrofitting of Masonry and Heritage Structures Based on Their Vulnerability Revealed in the Bam 2003 Earthquake
PublicationFor decades, one of the most critical considerations of civil engineers has been the construction of structures that can sufficiently resist earthquakes. However, in many parts of the globe, ancient and contemporary buildings were constructed without regard for engineering; thus, there is a rising necessity to adapt existing structures to avoid accidents and preserve historical artefacts. There are various techniques for retrofitting...
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Low-Voltage Low-Power Filters with Independent ω0 and Q Tuning for Electronic Cochlea Applications
PublicationAn acoustic second-order low-pass filter is proposed for filter banks emulating the operation of a human cochlea. By using a special filter structure and an innovative quality (Q)-factor tuning technique, an independent change of the cutoff frequency (ω0) and the Q-factor with unchanged gain at low frequencies is achieved in this filter. The techniques applied result in a simple filter design with low Q-factor sensitivity to component...
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Controlling crystallites orientation and facet exposure for enhanced electrochemical properties of polycrystalline MoO3 films
PublicationThis study focuses on the development and optimization of MoO3 films on commercially available FTO substrates using the pulsed laser deposition (PLD) technique. By carefully selecting deposition conditions and implementing post-treatment procedures, precise control over crystallite orientation relative to the substrate is achieved. Deposition at 450 °C in O2 atmosphere results in random crystallite arrangement, while introducing...
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Triangulation-based Constrained Surrogate Modeling of Antennas
PublicationDesign of contemporary antenna structures is heavily based on full-wave electromagnetic (EM) simulation tools. They provide accuracy but are CPU-intensive. Reduction of EM-driven design procedure cost can be achieved by using fast replacement models (surrogates). Unfortunately, standard modeling techniques are unable to ensure sufficient predictive power for real-world antenna structures (multiple parameters, wide parameter ranges,...
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Design of reverse curves adapted to the satellite measurements
PublicationThe paper presents a new method for designing railway route in the direction change area adapted to the Mobile Satellite Measurements technique. The method may be particularly useful in the situations when both tangents cannot be connected in an elementary way using a circular arc with transition curves. Thus, the only solution would be the application of two circular arcs of opposite curvature signs, that is, the use of an inverse...
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Accurate simulation-driven modeling and design optimization of compact microwave structures
PublicationCost efficient design optimization of microwave structures requires availability of fast yet reliable replacement models so that multiple evaluations of the structure at hand can be executed in reasonable timeframe. Direct utilization of full-wave electromagnetic (EM) simulations is often prohibitive. On the other hand, accurate data-driven modeling normally requires a very large number of training points and it is virtually infeasible...
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Full scale CFD seakeeping simulations for case study ship redesigned from V-shaped bulbous bow to X-bow hull form
PublicationIncreasing propulsion efficiency, safety, comfort and operability are of the great importance, especially for small ships operating on windy sites like the North Sea and the Baltic Sea. Seakeeping performance of ships and offshore structures can be analysed by different methods and the one that is becoming increasingly important is CFD RANS. The recent development of simulation techniques together with rising HPC accessibility...
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Mechanical Behavior of Bi-Layer and Dispersion Coatings Composed of Several Nanostructures on Ti13Nb13Zr Alloy
PublicationTitanium implants are commonly used because of several advantages, but their surface modification is necessary to enhance bioactivity. Recently, their surface coatings were developed to induce local antibacterial properties. The aim of this research was to investigate and compare me-chanical properties of three coatings: multi-wall carbon nanotubes (MWCNTs), bi-layer composed of an inner MWCNTs layer and an outer TiO2 layer, and...
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Analytical procedures for the determination of surfactants in environmental samples
PublicationBecause of their specific physical and chemical properties (amphiphilicity, solubility in polar and nonpolar liquids, ability to form micelles, adsorption at phase boundaries, low toxicity) surfactants (surface-active compounds) are widely applied in industry and in the household. As their applications are on a very large scale, it has become necessary to acquire a more detailed understanding of their environmental fate.In the...
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Application of gas chromatography to the analysis of spirit-based alcoholic beverages
PublicationSpirit-based beverages are alcoholic drinks, which production processes are dependent on the type and origin of raw materials. The composition of this complex matrix is difficult to analyze and scientists commonly choose a gas chromatography techniques for this reason. With a wide selection of extraction methods and detectors it is possible to provide qualitative and quantitative analysis for many chemical compounds with a various...
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Combined Close Range Photogrammetry and Terrestrial Laser Scanning for Ship Hull Modelling
PublicationThe paper addresses the fields of combined close-range photogrammetry and terrestrial laser scanning in the light of ship modelling. The authors pointed out precision and measurement accuracy due to their possible complex application for ship hulls inventories. Due to prescribed vitality of every ship structure, it is crucial to prepare documentation to support the vessel processes. The presented methods are directed, combined...
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Real-Time Volatilomics: A Novel Approach for Analyzing Biological Samples
PublicationThe use of the ‘omics techniques in environmental research has become common-place. The most widely implemented of these include metabolomics, proteomics, genomics, and transcriptomics. In recent years, a similar approach has also been taken with the analysis of volatiles from biological samples, giving rise to the so-called ‘volatilomics’ in plant analysis. Developments in direct infusion mass spectrometry (DI-MS) techniques have...
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TECHNIKI CAD W INŻYNIERII ELEKTRYCZNEJ - WYBRANE ZAGADNIENIA
PublicationW pracy przedstawiono różne techniki CAD (ang. Computer Aided Design) wykorzystywane w inżynierii elektrycznej dla potrzeb komputerowego modelowania 3D przetworników elektromechanicznych. Wirtualne modele 3D różnych urządzeń są użyteczne nie tylko przy opracowywaniu dokumentacji technicznej ale są także wykorzystywane w obliczeniach inżynierskich:...
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Substrate-integrated waveguide (SIW) filter design using space mapping
PublicationIn this paper, we present a fast technique for an automated design of microwave filters in substrate integrated wave (SIW) technology. The proposed methodology combines the space mapping technique with a cost function defined using the location of complex zeros and poles of filter’s transfer and reflection function and uses a rectangular waveguide as a surrogate model. The effectiveness of the proposed technique is presented with...
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Adaptive Expectation Maximization Smoothing (AEMS) inverse technique forindirect fish target strenght estimation. W: [CD-ROM] Full Papers. 6th ICES Symposium on Acoustics in Fisheries and Aquatic Ecology. Montpellier, 10-14 June 2002. [Montpellier: Ifremer]**2002, [6 s.] 5 rys. bibliogr. 5 poz. Zastosowanie adaptacyjnej metody EMS do pośredniej estymacji siły celu ryb.
PublicationW pracy przedstawiono modyfikację statystycznej metody EMS (ang. Expecta-tion, Maximization, Smoothing) stosowanej w zagadnienia odwrotnych, polega-jącą na iteracyjnym rozwiązaniu równania Fredholma. Pokazano jej zastosowa-nie do pośredniej estymacji siły celu ryb stosowanej dla danych pozyskanychprzez hydroakustyczne systemy jednowiązkowe wykorzystywane w przeszukiwa-niach akustycznych. Wyniki porównano z rezultatami uzyskanymi...
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Modern solutions in the field of microextraction using liquid as a medium of extraction
PublicationThe monitoring of compounds present in samples at trace/ultra-trace level usually requires a preliminary step of isolation and/or enrichment of analytes. Against, sample preparation is considered as crucial part of whole analytical procedures, in particular in samples characterized by complex matrices composition. Several new miniaturized extraction techniques is introduced and extensively applied to different type of samples....
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Aerodynamic shape optimization by variable-fidelity computational fluid dynamics models: a review of recent progress
PublicationA brief review of some recent variable-fidelity aerodynamic shape optimization methods is presented.We discuss three techniques that—by exploiting information embedded in low-fidelity computationalfluid dynamics (CFD) models—are able to yield a satisfactory design at a low computational cost, usu-ally corresponding to a few evaluations of the original, high-fidelity CFD model to be optimized. Thespecific techniques considered here...
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Narzędzia treningu twórczości jako pomoc w kształceniu projektantów
PublicationKreatywność rozwijać. Na tym założeniu opiera się międzynarodowy program edukacyjny Odyssey of the Mind (Odyseja Umysłu). W programie zespoły młodych osób pracują metodą projektową, wykorzystując różnorodne techniki treningu twórczości, nad rozwiązaniem abstrakcyjnego problemu rozbieżnego. Część absolwentów programu wybiera kierunki kreatywne jako naturalną kontynuację procesu edukacji. Elementy treningu twórczości można wykorzystać...
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Shooting Gas Cylinders to Prevent Their Explosion in Fire
PublicationGas cylinders in general, and particularly cylinders containing acetylene, constitute a great potential danger to fire and rescue services involved in salvage operations. Experiments show that gas cylinders with acetylene, oxygen, hydrogen, CNG, LPG or CO2 may blow after short exposition to heat with very destructive effect as fragments of blown cylinder may fly even several hundred meters. In the case of acetylene the explosion...
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Review of historical buildings' foundations
PublicationThe paper presents in brief the history of foundation engineering with a particular regard to its development, applied techniques and materials. Different types of old foundations in relation to various soil conditions are considered. Basic methods of preservation of old foundations, with special emphasis given to their faults and advantages are discussed. Finally, some problems of the reuse of pre-existing foundations are raised....
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Integration of thermographic data with the 3D object model
PublicationThe aim of the paper is to present new method for merging the 3D model data of the measured object with thermograms. Our technique is based on the combination of visual 3D imaging technique and thermal imaging technique, which maps the 2D thermograms on to 3D anatomical mesh model. The combination of these imaging modalities allows the generation of combined 3D and thermal data from which thermal signatures can be verified and...
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A New Direct-Sequence Spread Spectrum Signal Detection Method for Underwater Acoustic Communications in Shallow-Water Channel
PublicationDirect-Sequence Spread Spectrum (DSSS) is one of the modulation and coding techniques used in Underwater Acoustic Communication (UAC) systems for reliable data transmision even at low signal levels. However, in a shallow water channel, there is a strong multipath propagation which causes a phase fluctuation of the received signal, affecting the performance of the spread-spectrum system. The article presents a differential method...
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Design specification management with automated decision-making for reliable optimization of miniaturized microwave components
PublicationThe employment of numerical optimization techniques for parameter tuning of microwave components has nowadays become a commonplace. In pursuit of reliability, it is most often carried out at the level of full-wave electromagnetic (EM) simulation models, incurring considerable computational expenses. In the case of miniaturized microstrip circuits, densely arranged layouts with strong cross-coupling effects make EM-driven tuning...
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Evaluation of high-frequency roughness measurement errors for composite and ceramic surfaces after machining
PublicationPrecise characterisation of surface topography is of the greatest importance since many factors directly affect the accuracy of the whole measurement process. In this paper, the variety of surface topographies from machined composite and ceramic workpieces was studied with a special emphasis on the measurement results. Surfaces were subjected to the ground diamond, honing and milling processes. Measurement results were analysed...
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Domain segmentation for low-cost surrogate-assisted multi-objective design optimisation of antennas
PublicationAbstract: Information regarding the best possible design trade-offs of an antenna structure can be obtained through multiobjective optimisation (MO). Unfortunately, MO is extremely challenging if full-wave electromagnetic (EM) simulation models are used for performance evaluation. Yet, for the majority of contemporary antennas, EM analysis is the only tool that ensures reliability. This study introduces a procedure for accelerated...
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From Structure to Luminescent Properties of B2O3-Bi2O3-SrF2 Glass and Glass-Ceramics Doped with Eu3+ Ions
PublicationGlass-ceramics with the composition B2O3 -Bi2O3 -SrF2 were synthesized by the conventional melt-quenching technique and subsequent crystallization of the parental glasses. The temperature at which the ceramization was carried out was selected based on differential scanning calorimetry (DSC) analysis. The structure of the studied materials and the formation of SrF2 nanocrystals were confirmed by the Fourier-transform infrared spectroscopy...
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Recent advances in rapid multiobjective optimization of expensive simulation models in microwave and antenna engineering by Pareto front exploration
PublicationPractical engineering design problems are inherently multiobjective, that is, require simultaneous control of several (and often conflicting) criteria. In many situations, genuine multiobjective optimization is required to acquire comprehensive information about the system of interest. The most popular solution techniques are populationbased metaheuristics, however, they are not practical for handling expensive electromagnetic...
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Rapid simulation-driven design of miniaturised dual-band microwave couplers by means of adaptive response scaling
PublicationOne of the major challenges in the design of compact microwave structures is the necessity of simultaneous handling of several objectives and the fact that expensive electromagnetic (EM) analysis is required for their reliable evaluation. Design of multi-band circuits where performance requirements are to be satisfied for several frequencies at the same time is even more difficult. In this work, a computationally efficient design...
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Mechatronic Design Towards Investigation of the Temporo-Mandibular Joint Behaviour
PublicationA significant problem of the temporo-mandibular joint (TMJ) research is lack of data concerning geometry and position of TMJ discs. It leads to necessity of developing a driving method of the process optimization, which is based on chosen techniques of mechatronic design. In particular, the latter concerns a technique of experimentally supported virtual prototyping. On this stage, the research is characterized by well-verified...
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CURRENT TRENDS IN RECYCLING OF PHOTOVOLTAIC SOLAR CELLS AND MODULES WASTE
PublicationIn comparison to other energy producing techniques, photovoltaics (PV) is one of the most promising options: no emission of any matter into the environment during operation; extremely long operation period (estimated average: 25 years), minimum maintenance, robust technique, aesthetic aspects. The use of photovoltaics is rapidly increasing, and the respective market is developing accordingly. Although PV manufacturing equipment...
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Recycling of Photovoltaic Solar Cells and Modules - Te State - Of - Art
PublicationIn comparison to other energy producing techniques, photovoltaics (PV) is one of the most promising options: no emission of any matter into the environment during operation; extremely long operation period (estimated average: 25 years), minimum maintenance, robust technique, aesthetic aspects. The use of photovoltaics is rapidly increasing, and the respective market is developing accordingly. Although PV manufacturing equipment...
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Enhancing Availability for Critical Services
PublicationTraditional approaches to provide classes of resilient service take the physical network availability as an input and then deploy redundancy and restoration techniques at various layers, often without full knowledge of mappings between layers. This makes it hard (and often inefficient) to ensure the high availability required by critical services which are typically a small fraction of the total traffic. Here, the innovative technique...
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Classification and fingerprinting of kiwi and pomelo fruits by multivariate analysis of chromatographic and spectroscopic data
PublicationThe fingerprinting capacity of two analytical techniques, HPLC and UV-Vis spectroscopy in the case of fruits samples (kiwi and pomelo) has been investigated. The multivariate exploratory techniques were used for sample discrimination according to the fruit species and subspecies. The combination of principal component analysis with linear discriminant analysis is opening new directions in the fingerprinting analysis. The classifications...
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Soft-decision schemes for radar estimation of elevation at low grazing angles
PublicationIn modern radars, the problem of estimating elevation angle at low grazing angles is typically solved using superresolution techniques. These techniques often require one to provide an estimate of the number of waveforms impinging the array, which one can accomplish using model selection techniques. In this paper, we investigate the performance of an alternative approach, based on the Bayesian-like model averaging. The Bayesian...
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Analysis of arsenic species in environmental samples
PublicationMany analytical methods for determining arsenic in various forms in environmental samples have been developed in recent years. The main objective of this review article is the presentation and comparison of the three principal techniques for the determination arsenic compounds, namely: hydride generation (HG), voltammetry and chromatography (liquid chromatography including high-performance liquid chromatography (HPLC), and gas...
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Real-time monitoring of volatiles and particles emitted from thermoplastic filaments during 3D printing
PublicationPresentation on the use of instrumental analytical techniques for the assessment of emission of volatiles and particulates during fdm 3d printing.
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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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Analysis of circular cavity with cylindrical objects
PublicationArtykuł opisuje analizę rozpraszania fali elektromagnetycznej na obiektach cylindrycznych rozmieszczonych dowolnie w strukturze rezonatora. Analiza oparta jest na metodzie dopasowania rodzajów. Dokładność i poprawność metody jest zweryfikowana poprzez porównanie uzyskanych wyników z wynikami otrzymanymi z metod alternatywnych i własnych pomiarów wykonanych układów.
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Projection framework for hybrid methods derived from finite difference operators in time and frequency domain
PublicationW artykule przedstawiono ogólną koncepcję tworzenia algorytmów hybrydowych na bazie operatorowego sformułowania metody różnic skończonych. Wykorzystano koncepcję projekcji ortogonalnej w przestrzeni skończeniewymiarowej w celu modyfilacji pierwotnego sformułowania.
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Equivalent spice circuits with guaranteed passivity from nonpassive models
PublicationW artykule przedstawiona została nowa technika wymuszania pasywności schematów zastępczych. Opracowana technika pozwala na konstrukcję schematów zastępczych bardzo złożonych układów, oraz pozwala na wymuszenie pasywności modelu tworzonego na podstawie danych niepasywnych.
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Quadratic programming approach to coupled resonator filter cad
PublicationArtykuł prezentuje technikę komputerowego wspomagania procesu projektowania filtrów zbliżeniowych. Polega ona na sformułowaniu macierzy sprzężeń jako problemu programowania kwadratowego (QP). Dzięki zdefiniowaniu procedury optymalizacyjnej jako problemu QP, przy założeniu liniowej zależności współczynników sprzężeń od wymiarów geometrycznych struktury, uzyskano znaczącą redukcję liczby pełnofalowych symulacji prowadzących do uzyskania...
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Transanal Endoscopic Microsurgery via TriPort Access System With No General Anesthesia and Without Sphincter Damage
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Dimensional Synthesis of Coupled-Resonator Pseudoelliptic Microwave Bandpass Filters with Constant and Dispersive Couplings
PublicationIn this paper, we propose a novel technique for the dimensional synthesis of coupled-resonator pseudoelliptic microwave filters with constant and dispersive couplings. The proposed technique is based on numerical simulations of small structures, involving up to two adjacent resonators, and it accounts for a loading effect from other resonators by replacing them with terminations coupled through appropriately scaled inverters. The...
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Simulating malware with MAlSim
PublicationThis paper describes MAlSim - Mobile Agent Malware Simulator - a mobile agent framework developed to address one of the most important problems related to the simulation of attacks against information systems, i.e. the lack of adequate tools for reproducing behaviour of malicious software (malware). The framework can be deployed over the network of an arbitrary information system and it aims at simulating behaviour of each instance...
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Efficient and Systematic Solution of Real and Complex Eigenvalue Problems Employing Simplex Chain Vertices Searching Procedure
PublicationW artykule zaprezentowano nowatorską metodę, pozwalającą w bardzo efektywny sposób rozwiązywać rzeczywiste i zespolone zagadnienia własne (które przekształcić można w równania nieliniowe) często spotykane w elektrodynamice obliczeniowej. Idea metody oparta jest o śledzenie miejsc zerowych otrzymanego równania nieliniowego. W proponowanej technice zastosowano regularne wielościany, budując z nich łańcuch (ścieżkę) poszukiwanych...
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Biomechanics of the front abdominal wall as a potential factorleading to recurrence with laparoscopic ventral hernia repair
PublicationThis study investigated the front abdominal wallto describe its elasticity in vivo and searched for elongationsthat possibly stretched an implanted mesh, therebycausing fixation failure and subsequent recurrence.To measure front abdominal wall elongations, amodel of fascia movements was created. Eight healthyvolunteers were measured during exercise to determine theextent of elongations in their front abdominal wall. Videoswere...
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Rapid Yield Estimation and Optimization of Microwave Structures Exploiting Feature-Based Statistical Analysis
PublicationIn this paper, we propose a simple, yet reliable methodology to expediteyield estimation and optimization of microwave structures. In our approach,the analysis of the entire response of the structure at hand (e.g., $S$-parameters asa function of frequency) is replaced by response surface modeling of suitablyselected feature points. On the one hand, this is sufficient to determinewhether a design satisfies given performance specifications....