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Tendencje w projektowaniu mieszkań dla seniorów = Contemporary design trends in housing for seniors
Publikacjawe wspolczesnym społeczeństwie zaistniała paradoksalna sytuacja wyobcowania osób starszych z problematyki modelowania bezpiecznego i przyjaznego środowiska życia Na tym tle przedstawiono analizę wybranych realizacji z dziedziny budownictwa dla osób 60+ ( analizując kontekst sytuacyjny, krajobrazowy,walory funkcjonalne i uzytkowe,innowacyjnosć technologiczną, indywidualny wyraz architektoniczny projektów i realizacji polskich i...
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Novel structure and size-reduction-oriented design of microstrip compact rat-race coupler
PublikacjaIn this paper, a novel structure of a miniaturized microstrip rat-race coupler has been proposed. Surrogate-based optimization procedures are applied to explicitly reduce the coupler size while maintaining equal power split at the operating frequency of 1 GHz and sufficient bandwidth for return loss and isolation characteristics. The optimization is performed using the objective function with four penalty components. The footprint...
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Low-cost multi-objective design of compact microwave structures using domain patching
PublikacjaA good compromise between size and electrical performance is an important design consideration for compact microwave structures. Comprehensive information about size/performance trade-offs can be obtained through multi-objective optimization. Due to considerable electromagnetic (EM) cross-couplings in highly compressed layouts, the design process has to be conducted at the level of high-fidelity EM analysis which is computationally...
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Design and experimental investigations of a cylindrical microjet heat exchanger for waste heat recovery systems
PublikacjaCompact heat exchangers have more and more applications in many areas, including the HVAC, food and petrochemical industry. This paper describes the development of heat exchanger technology for waste heat recovery (WHR) from a range of processes. Case-study testing shows that the proposed heat exchanger can successfully enhance heat transfer and recover waste heat in a range of applications making them economically, environmentally and...
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Rapid multi-objective design optimization of miniaturized impedance transformer by Pareto front exploration
PublikacjaFast multi-objective optimization of compact impedance transformer is discussed. A set of alternative designs representing possible trade-offs between conflicting design criteria, i.e., electrical performance (here, wideband matching) and the structure size, is obtained through Pareto front exploration by means of surrogate-assisted methods.
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Cost-efficient multi-objective design optimization of antennas in highly-dimensional parameter spaces
PublikacjaMulti-objective optimization of antenna structures in highly-dimensional parameter spaces is investigated. For expedited design, variable-fidelity EM simulations and domain patching algorithm are utilized. The results obtained for a monopole antenna with 13 geometry parameters are compared with surrogate-assisted optimization involving response surface approximation modeling.
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User -friendly E-learning Platform: a Case Study of a Design Thinking Approach Use
PublikacjaE-learning systems are very popular means to support the teaching process today. These systems are mainly used by universities as well as by commercial training centres. We analysed several popular e-learning platforms used in Polish universities and find them very unfriendly for the users. For this reason, the authors began the work on the creation of a new system that would be not only useful, but also usable for students, teachers...
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Evolutionary design of combinational digital circuits: state of the art, main problems, and future trends
PublikacjaW artykule przedstawiono stan obecny, główne problemy oraz perspektywy dotyczące ewolucyjnego projektowania kombinacyjnych układów cyfrowych. Krótko scharakteryzowano istniejące algorytmy ewolucyjnego projektowania układów kombinacyjnych oraz przedstawiono ich ogólną koncepcję. wskazano również główne problemy tych algorytmów oraz potencjalne sposoby ich eliminacji.
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Programmable feedforward linearized CMOS OTA for fully differential continuous-time filter design
PublikacjaW artykule przedstawiono metodę linearyzacji wzmacniacza transkonduktancyjnego (OTA) CMOS z zastosowaniem sprzężenia w przód. Wzmacniacz zbudowany jest z użyciem prostych par różnicowych, wzmacniacza w pętli sprzężenia zwrotnego do samoregulacji transkonduktancji wzmacniaczy oraz liniowej rezystancji odniesienia (R). W wyniku uzyskano znaczną linaryzację charakterystyk przejściowych wzmacniacza OTA. Symulacje komputerowe SPICE...
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Design of high frequency OTA in 130nm CMOS technology with single 1.2v power supply
PublikacjaW artykule przedstawiono wzmacniacz transkonduktancyjny OTA zasilany niskim napięciem i przeznaczony do użycia w filtrach czasu ciągłego w zakresie wysokich częstotliwości przetwarzanych sygnałów. Stopień wejściowy zbudowany jest w oparciu o inwertery CMOS. Wartość transkonduktancji wzmacniacza jest przestrajana z wykorzystaniem efektu podłożowego tranzystorów. Omówiono również układ dostrajania wzmacniacza. Brak wewnętrznych węzłów...
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A decision-making module for aiding ship system automation design; A knowledge-based approach
PublikacjaZastosowanie elementów sztucznej inteligencji, w tym systemów z bazą wiedzy staje się coraz bardziej powszechne przy komputerowo wspomaganym projektowaniu. Proces projektowy związany jest z wieloma problemami decyzyjnymi, jak: wybór struktury podsystemu, podzespołów czy też elementów składowych. Z tego względu zdecydowano się opracować system z bazą wiedzy z modułem wspirającym proces podejmowania decyzji.W artykule przedstawiono...
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Influence of main design parameters of ship propeller shaft water-lubricated bearings on their properties
PublikacjaW artykule omówiono wpływ głównych parametrów konstrukcyjnych i eksploatacyjnych takich jak wielkość luzu łożyskowego, własności materiału panwi, stanu powierzchni skojarzenia ślizgowego oraz temperatury i zasolenia wody na nośność hydrodynamiczną łożyska okrętowego wału śrubowego smarowanego wodą.
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Equivalent axle load factors for design of rigid pavements derived from fatigue criteria
PublikacjaArtykuł przedstawia określenie współczynników równoważności osi dla nawierzchni sztywnych na podstawie kryteriów zmęczeniowych stosowanych w mechanistyczno-empirycznej metodzie projektowania nawierzchni drogowych. Przedstawiono kryteria zmęczeniowe z wybranych metod projektowania i analizy nawierzchni sztywnych. Kryteria te zostały użyte do wyprowadzenia wzorów do obliczania współczynników równoważności obciążenia osi. Stwierdzono,...
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A new design of the poded azimuth thruster for a diesel-hydraulic propulsion system of a small vessel
PublikacjaW artykule przedstawiono analizę różnych rodzajów okrętowych systemów napędowych z pędnikami azymutalnymi oraz rozwiązanie konstrukcyjne pędnika przeznaczonego dla małego statku z napędem diesel-hydraulicznym.Cechą charakterystyczna tego rozwiązania jest umieszczenie pod wodą głównego hydraulicznego silnika, napedzającego śrubę o skoku stałym mieszczoną w dyszy. Silnik zamocowany do gondoli połączonej sztywno z pionowową kolumną...
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An Automated Design of Substrate Integrated Waveguide Filters Based on Implicit Space Mapping Optimization
Publikacja -
Zero-pole approach to computer aided design of in-line siw filters with transmission zeros
PublikacjaThis paper presents a design of a new type of in-line pseudo-elliptic filters implemented in substrate integrated waveguide(SIW) technology. To realize transmission zeros in in-line topology,frequency-dependent couplings were used. Such dispersive couplingswere implemented as shorted stubs. The design process startswith the generation of a suitable starting point. To this end, anapproximation of SIW as a rectangular waveguide is...
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Passive Variable Fractional Delay Filter Design using Distributed Maximal Flatness Method
PublikacjaW pracy przedstawiono nową metodę projektowania pasywnych filtrów ułakowoopóźniających opartą na metodzie rozproszonej maksymalnej płaskości. W zaproponowane podejście jest uogólnieniem najbardziej popularnej metody projektowania filtrów maksymalnie płaskich - metody projektowania filtrów maksymalnie płaskich. Filtr maksymalnie płaski cechuje bardzo dobra jakość jedynie w wąskim paśmie wokół częstotliwości zerowej, ale jego istotną...
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A bisection‐based heuristic for rapid EM‐driven multiobjective design of compact impedance transformers
PublikacjaDesign of microwave structures is a multiobjective task where several conflicting requirements have to be considered at the same time. For contemporary circuits characterized by complex geometries, multiobjective optimization cannot be performed using standard population‐based algorithms due to high cost of electromagnetic (EM) evaluations. In this work, we propose a deterministic approach for fast EM‐driven multiobjective design...
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Constrained optimization for generating gain-bandwidth design trade-offs of wideband unidirectional antennas
PublikacjaBroadband unidirectional antennas realised in microstrip technology find applications in many wireless communication systems. One of their design challenges is the necessity of handling multiple performance figures which is difficult when using traditional design methods, largely based on parameter sweeping. This work presents a simple optimisation-based framework that permits generation of gain-bandwidth trade-off designs for...
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Reduced-cost design closure of antennas by means of gradient search with restricted sensitivity update
PublikacjaDesign closure, i.e., adjustment of geometry parameters to boost the performance, is a challenging stage of antenna design process. Given complexity of contemporary structures, reliable parameter tuning requires numerical optimization and can be executed using local algorithms. Yet, EM-driven optimization is a computationally expensive endeavour and reducing its cost is highly desirable. In this paper, a modification of the trust-region...
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Adaptabilność obiektów architektonicznych we współczesnym projektowaniu / The adaptability of architectural objects in contemporary design
PublikacjaThe article discusses the issue of adaptability - the ability to modify modern architectural objects to a changing context - as an important element of contemporary design. Adaptability can take on different forms. It is most commonly understood as a change in the architectural form in reaction to various stimuli from the environment through transformative structures, or as an object's ability to adapt to climatic conditions, providing...
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A design framework for rigorous constrained EM-driven optimization of miniaturized antennas with circular polarization
PublikacjaCompact radiators with circular polarization are important components of modern mobile communication systems. Their design is a challenging process which requires maintaining simultaneous control over several performance figures but also the structure size. In this work, a novel design framework for multi-stage constrained miniaturization of antennas with circular polarization is presented. The method involves sequential optimization...
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A Generalized SDP Multi-Objective Optimization Method for EM-Based Microwave Device Design
PublikacjaIn this article, a generalized sequential domain patching (GSDP) method for efficient multi-objective optimization based on electromagnetics (EM) simulation is proposed. The GSDP method allowing fast searching for Pareto fronts for two and three objectives is elaborated in detail in this paper. The GSDP method is compared with the NSGA-II method using multi-objective problems in the DTLZ series, and the results show the GSDP method...
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Multi-Fidelity Local Surrogate Model for Computationally Efficient Microwave Component Design Optimization
PublikacjaIn order to minimize the number of evaluations of high-fidelity (“fine”) model in the optimization process, to increase the optimization speed, and to improve optimal solution accuracy, a robust and computational-efficient multi-fidelity local surrogate-model optimization method is proposed. Based on the principle of response surface approximation, the proposed method exploits the multi-fidelity coarse models and polynomial interpolation...
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Domain segmentation for low-cost surrogate-assisted multi-objective design optimisation of antennas
PublikacjaAbstract: 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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Design and optimization of a novel miniaturized low-profile circularly polarized wide-slot antenna
PublikacjaThis paper presents a novel structure of a compact circularly polarized (CP) antenna. CP is obtained using a parasitic quasi-rectangular strip placed coplanar to the feedline. A ground plane perturbation combined with the asymmetric geometry of the coplanar waveguide ground planes is utilized to excite additional CP modes. All antenna dimensions are rigorously optimized to achieve the best possible performance in terms of the impedance...
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Statistical analysis and robust design of circularly polarized antennas using sequential approximate optimization
PublikacjaIn the paper, reliable yield estimation and tolerance-aware design optimization of circular polarization (CP) antennas is discussed. We exploit auxiliary kriging interpolation models established in the vicinity of the nominal design in order to speed up the process of statistical analysis of the antenna structure at hand. Sequential approximate optimization is then applied to carry out robust design of the antenna, here, oriented...
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Rapid design closure of microwave components by means of feature-based optimization and adjoint sensitivities
PublikacjaIn this article, fast design closure of microwave components using feature-based optimization (FBO) and adjoint sensitivities is discussed. FBO is one of the most recent optimization techniques that exploits a particular structure of the system response to “flatten” the functional landscape handled during the optimization process, which leads to reducing its computational complexity. When combined with gradient-based search involving...
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Regression points in non-intrusive polynomial chaos expansion method and D-optimal design
PublikacjaThe paper addresses selected issues of uncertainty quantification in the modelling of a system containing surgical mesh used in ventral hernia repair. Uncertainties in the models occur e.g. due to variability of abdominal wall properties among others. In order to include them, a non-intrusive regression-based polynomial chaos expansion method is employed. Its accuracy depends on the choice of regression points. In the study a relation...
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Expedited Design Closure of Antennas By Means Of Trust-Region-Based Adaptive Response Scaling
PublikacjaIn the letter, a reliable procedure for expedited design optimization of antenna structures by means of trust-region adaptive response scaling (TR-ARS) is proposed. The presented approach exploits two-level electromagnetic (EM) simulation models. A predicted high-fidelity model response is obtained by applying nonlinear frequency and amplitude correction to the low-fidelity model. The surrogate created this way is iteratively rebuilt...
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Design of a Shape-Memory-Alloy-Based Carangiform Robotic Fishtail with Improved Forward Thrust
PublikacjaShape memory alloys (SMAs) have become the most common choice for the development of mini- and micro-type soft bio-inspired robots due to their high power-to-weight ratio, ability to be installed and operated in limited space, silent and vibration-free operation, biocompatibility, and corrosion resistance properties. Moreover, SMA spring-type actuators are used for developing different continuum robots, exhibiting high degrees...
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Design and Implementation of Multi-Band Reflectarray Metasurface for 5G Millimeter Wave Coverage Enhancement
PublikacjaA compact low-profile multi-band millimeter-wave (mm-wave) reflectarray metasurface design is presented for coverage enhancement in 5G and beyond cellular communication. The proposed single-layer metasurface exhibits a stable reflection response under oblique incidence angles of up to 60o at 24 and 38 GHz, and transmission response at 30 GHz, effectively covering the desired 5G mm-wave frequency bands. The proposed reflectarray...
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TR-Based Antenna Design with Forward FD: The Effects of Step Size on the Optimization Performance
PublikacjaNumerical methods are important tools for design of modern antennas. Trust-region (TR) methods coupled with data-efficient surrogates based on finite differentiation (FD) represent a popular class of antenna design algorithms. However, TR performance is subject to FD setup, which is normally determined a priori based on rules-of-thumb. In this work, the effect of FD perturbations on the performance of TR-based design is evaluated...
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Design of hight voltage busbar: trade off between electrical field and stray inductance
PublikacjaArtykuł dotyczy optymalizacji konstrukcji i technologii szyny doprowadzenia zasilania do pojedynczej gałęzi falownika średniego napięcia. Dla szeregowego układu złożonego z trzech modułów elektroizolowanych (6 par tranzystorów i diod) rozważono warianty geometrii szyny zasilania przy uwzględnieniu wypadkowej indukcyjności obwodu komutacyjnego. Wyznaczono główne składniki indukcyjności rozproszenia oraz wykazano jej wpływ na przepięcia...
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Design of a Cellular Dual-Band Sticker Antenna for Thickness-Independent 3D-Printed Substrates
PublikacjaAdditive manufacturing technology provides high flexibility in designing custom enclosures for prototype devices such as nodes of distributed sensor networks. Although integration of components is desired from the perspective of sensor mobility, it might negatively affect the performance of radio-connectivity due to couplings between the antenna and system peripherals, as well as other unaccounted effects of the 3D printed enclosure....
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Polyether-block-amide PEBA membranes for gas separation and pervaporation; current design and applications
PublikacjaPolyether-block-amide (PEBA) membranes have attracted considerable attention for their exceptional efficacy in gas separation and pervaporation processes. This comprehensive review delves into the precise definition, distinguishing characteristics, and diverse applications of PEBA membranes over the past five years. A primary research objective focuses on enhancing gas separation efficiency, primarily through augmenting membrane...
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Nested Space Mapping Technique for Design and Optimization of Complex Microwave Structures with Enhanced Functionality
PublikacjaIn this work, we discuss a robust simulation-driven methodology for rapid and reliable design of complex microwave/RF circuits with enhanced functionality. Our approach exploits nested space mapping (NSM) technology, which is dedicated to expedite simulation-driven design optimization of computationally demanding microwave structures with complex topologies. The enhanced func-tionality of the developed circuits is achieved by means...
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EM-Driven Multi-Objective Optimization of Antenna Structures in Multi-Dimensional Design Spaces
PublikacjaFeasible 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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Design space reduction and variable-fidelity EM simulations for feasible Pareto optimization of antennas
PublikacjaA 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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Rapid EM-Driven Design of Compact RF Circuits By Means of Nested Space Mapping
PublikacjaA methodology for rapid design of RF circuits constituted by compact microstrip resonant-cells (CMRCs) is presented. Our approach exploits nested space mapping (NSM) technology, where the inner SM layer is used to correct the equivalent circuit model at the CMRC level, whereas the outer layer enhances the coarse model of the entire structure under design. We demonstrate that NSM dramatically improves performance of surrogate-based...
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Expedited EM-driven multi-objective antenna design in highly-dimensional parameter spaces
PublikacjaA 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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Simulation of fluid structure interaction in a novel design of high pressure axial piston pump
PublikacjaA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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Role patterns in IT projects teams - design of a selection module using fuzzy logic techniques
PublikacjaPresented paper introduces an approach based on usage of role patterns and modelling by the use of fuzzy logic tool for selection process with limitation to the area of IT projects environment. The article shows a concept of role patterns structures and their further usage in process of forming a fuzzy model dedicated to candidate assessment process support
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Local-Global Space Mapping for Rapid EM-Driven Design of Compact RF Structures
PublikacjaIn 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 biochemical multi-species quality model of a drinking water distribution system for simulation and design
PublikacjaDrinking Water Distribution Systems (DWDSs) play a key role in sustainable development of modern society. They are classified as critical infrastructure systems. This imposes a large set of highly demanding requirements on the DWDS operation and requires dedicated algorithms for on-line monitoring and control to tackle related problems. Requirements on DWDS availability restrict the usability of the real plant in the design phase....
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Research, theories and practical experience of therapeutic landscapes as a tool for urban open space design
PublikacjaThis paper reviews the research on therapeutic landscapes and discusses the design of urban parks and open green space. Firstly, the most relevant research on therapeutic landscapes is reviewed. Secondly, the practical experience of healing and therapeutic gardens is discussed. Finally, the conclusions leading to future use of therapeutic landscape concept in urban open space design are presented.
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Optimization of a Fabry-Perot Sensing Interferometer design for an optical fiber sensor of hematocrit level
PublikacjaContinuous measurement of the hemato crit level in blo o d can p otentially b e p erformed using optical bre sensors. The FabryPerot interferometric sensors are a promising candidate in this application. The most imp ortant step in the design of the sensor is design of the sensing interferometer. Adequate cavity length and high interference contrast are two most imp ortant requirements in this application. The design metho d of...
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Design considerations for compact microstrip resonant cells dedicated to efficient branch-line miniaturization
PublikacjaA conventional compact microstrip resonant cell (CMRC)has been thoroughly investigated to enhance its slow-wave properties and subsequently ensure an efficient miniaturization of a microstrip circuit. The geometry of a classic CMRC has been improved in terms of slowwave effect in two progressive steps: (i) a single-element topology has been replaced with a double-element one and (ii) a high-impedance section has been refined by...
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Space-mapping-based design flow of miniaturized broadband matching transformer with perforated metallization
PublikacjaA fast design procedure of unconventional passive components has been presented and experimentally validated on the basis of a wideband microstrip four-section matching transformer (50:6 OHm). A classic impedance matching circuit has been miniaturized by means of compact microstrip resonant cells (CMRCs) leading to a considerable length reduction (34%) together with minor degradation in its performance. The spacemapping-based design...
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Rapid design optimization of antennas using variable-fidelity EM models and adjoint sensitivities
PublikacjaPurpose – Development of techniques for expedited design optimization of complex and numerically expensive electromagnetic (EM) simulation models of antenna structures validated both numerically and experimentally. The paper aims to discuss these issues. Design/methodology/approach – The optimization task is performed using a technique that combines gradient search with adjoint sensitivities, trust region framework, as well as...