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Wielopoziomowy przekształtnik trakcyjny SiC z izolacją od sieci 3kV DC realizowaną za pomocą transformatorów 30kHz do napędów EZT
PublicationW referacie przedstawiono wielopoziomowy izolowany kaskadowy przekształtnik DC-AC z tranzystorami SiC MOSFET 1,2kV, przeznaczony do napędów elektrycznych zespołów trakcyjnych (EZT). Zaproponowana konstrukcja przekształtnika, przeznaczonego do pracy przy zasilaniu z sieci trakcyjnej 3kV DC, spełnia założenia energoelektronicznego transformatora trakcyjnego (z ang. Power Electronic Traction Transformer). Budowa modułowa z niskonapięciowych...
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Quechers sample preparation method variants for analysis of pesticide residues in fruits and vegetables
PublicationThis article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography coupled to MS or ECD for detection. The sample preparation approach is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged and safe. It is a combination of liquid-liquid...
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A Review: Structural Shape and Stress Control Techniques and their Applications
PublicationThis review article presents prior studies on controlling shape and stress in flexible structures. The study offers a comprehensive survey of literature concerning the adjustment and regulation of shape, stress, or both in structures and emphasizes such control’s importance. The control of systems is classified into three primary classes: nodal movement control, axial force control, and controlling the two classes concurrently....
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Implementation of high-precision computation capabilities into the open-source dynamic simulation framework YADE
PublicationThis paper deals with the implementation of arbitrary precision calculations into the open-source discrete element framework YADE published under the GPL-2+ free software license. This new capability paves the way for the simulation framework to be used in many new fields such as quantum mechanics. The implementation details and associated gains in the accuracy of the results are discussed. Besides the "standard" double (64 bits)...
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Investigation of the Effect of The Temperature and Magnetization Pattern on Flux Density, Instantaneous Torque, Unbalanced Magnetic Forces of a Surface Inset PMM
PublicationElectrical machines utilized in domestic applications such as ceiling fans should have low losses and cost. Permanent magnets are used instead of rotor excitation to reduce losses. Therefore, not only the losses of the rotor winding are eliminated, but also the efficiency of the machine is increased. A surface inset consequent pole (SICP) machine has also been used to reduce costs. Because less magnets are utilized in this structure....
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Fast Multi-Objective Optimization of Narrow-Band Antennas Using RSA Models and Design Space Reduction
PublicationComputationally efficient technique for multi-objective design optimization of narrow-band antennas is presented. In our approach, the corrected low-fidelity antenna model (obtained through coarse-discretization EM simulations) is enhanced using frequency scaling and response correction, sampled, and utilized to obtain a fast response surface approximation (RSA) antenna surrogate. The RSA model is constructed in the reduced design space....
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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....
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Verification of ESPAR Antennas Performance in the Simple and Calibration Free Localization System
PublicationThis paper presents the results of simulations and measurements of an indoor localization system that uses Electronically Steerable Parasitic Array Radiator (ESPAR) antennas with switched directional beam. Proposed antennas are dedicated for 2.4GHz ISM low-cost applications where determination of the incoming signal is required. The antennas performance is analyzed and verified with relation to positioning methods based on the...
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Methodological issues of functional safety and reliability assessment of critical systems in industrial hazardous plants
PublicationThe aim of this article is to identify and discuss some methodological issues that are of interest among functional safety specialists and experts after publication of the second edition of international standards IEC 61508 and IEC 61511, including the design and implementing the safety-related functions of higher safety integrity levels and protection layers. The basic role of safety-related systems is to reduce effectively and...
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Fast simulation-driven design optimization of UWB band-notch antennas
PublicationIn this letter, a simple yet reliable and automated methodology for rapid design optimization of ultra-wideband (UWB) band-notch antennas is presented. Our approach is a two-stage procedure with the first stage focused on the design of the antenna itself, and the secondstage aiming at identification of the appropriate dimensions of the resonator with the purpose of allocating the band-notch in the desired frequency range. For the...
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A New Coupler Concept for Contactless High-Speed Data Transmission Monitoring
PublicationThis paper presents a new concept of a couplerthat can be applied to high-speed data transmission contactlessmeasurements. The proposed approach is dedicated for differentialsignal transmission monitoring in microstrip coupled lineson printed circuit boards (PCBs). The coupler, produced on aseparate PCB, is overlayed on the transmission line with thedifferential signal and delivers decoupled differential signal tothe main measurement...
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Tuning matrix-vector multiplication on GPU
PublicationA matrix times vector multiplication (matvec) is a cornerstone operation in iterative methods of solving large sparse systems of equations such as the conjugate gradients method (cg), the minimal residual method (minres), the generalized residual method (gmres) and exerts an influence on overall performance of those methods. An implementation of matvec is particularly demanding when one executes computations on a GPU (Graphics...
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Taguchi sensors under temperature modulation
PublicationSemiconductor gas sensors are widely used in gas- analyzing applications for various gas species determination due to their low cost and possibility to detect number of different gases. However, one of the main problems with such sensors is their lack of selectivity. To overcome this issue different ap- proaches can be used. One of them is the operation with sensor temperature modulation combined with dedicated data process- ing...
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Expedited design of microstrip antenna subarrays using surrogate-based optimization
PublicationComputationally efficient simulation-driven design of microstrip antenna subarrays is presented. The proposed design approach aims at simultaneous adjustment of all relevant geometry parameters of the subarray, which allows us to take into account the effect of the feeding network on the subarray radiation pattern (in particular, the side lobe level, SLL). In order to handle a large number of variables involved in the design process,...
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ISSUES OF ECONOMIC ANALYSIS OF ELECTRIC ENERGY GENERATION IN A FLOATING POWER PLANT
PublicationThis article presents basic dependences for conducting a technical and economic analysis related with investment projects. It describes a combined system of a compression ignition engine and a steam turbine, whose aim, when placed on a floating platform, is to generate electric energy in the so-called distributed generation system. Such a system involves a reciprocating internal combustion engine and a connected steam turbine system...
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New oryginal generic technologies: A Polish R&D strategic implementation programme
PublicationPolands's pharmaceutical industry is of great significance to the whole economy. According to Forbs (2 October 2012), the cost of launching a new drug varies from USD 1 to 11 bilion. There is little Chance of a Polish pharmaceutical company developing an original drug due to financial reason.Many research teams in Poland take up research projects aimed at new biologically active compounds. But such an objective has no broader perspective,...
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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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Three-objective antenna optimization by means of kriging surrogates and domain segmentation
PublicationIn this paper, an optimization framework for multi-objective design of antenna structures is discussed which exploits data-driven surrogates, a multi-objective evolutionary algorithm, response correction techniques for design refinement, as well as generalized domain segmentation. The last mechanism is introduced to constrain the design space region subjected to sampling, which permits reduction of the number of training data samples...
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Rapid Design Tuning of Miniaturized Rat-Race Couplers Using Regression-Based Equivalent Network Surrogates
PublicationA simple technique for fast design tuning of compact rat-race couplers is presented. Our approach involves equivalent circuit representation, corrected by nonlinear functions of frequency with coefficients extracted through nonlinear regression. At the same time, the tuning process connects two levels of coupler representation: EM simulation of the entire circuit and re-optimization of the coupler building blocks (slow-wave cells...
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Rapid surrogate-assisted statistical analysis of compact microstrip couplers
PublicationIn this paper, a technique for low-cost statistical analysis and yield estimation of compact microwave couplers has been presented. The analysis is executed at the level of a fast surrogate model representing selected characteristic points of the coupler response that are critical to determine satisfaction/violation of the prescribed design specifications. Because of less nonlinear dependence of the characteristic points on geometry...
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Influence of Aggregating Window Size on Disparity Maps Obtained from Equal Baseline Multiple Camera Set (EBMCS)
PublicationThis paper is concerned with obtaining disparity maps on the basis of images from Equal Baseline Multiple Camera Set (EBMCS). EBMCS consists of a central camera and side cameras. Algorithms for obtaining disparity maps with the use of EBMCS take advantage of aggregating windows similarly to stereo matching algorithms for a stereo camera, a camera matrix or a camera array. The paper analyzes the influence of aggregating window size...
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Market Regeneration in Line with Sustainable Urban Development
PublicationThis article presents the study of the optimal design solutions for regeneration of marketplaces. It examines the design variants for the revitalisation of the marketplace, in particular, investment in their modernisation in order to find the most optimal model for transforming these public spaces to have a significant impact on the city’s development. The research is a comparative analysis of the implementation of regeneration...
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Recent and Emerging Applications of Graphene-based metamaterials in Electromagnetics
PublicationSurface Plasmon Polaritons (SPPs) operating in mid-infrared up to terahertz (THz) frequencies have been traditionally manufactured on expensive metals such as gold, silver, etc. However, such metals have poor surface confinement that limits the optical applications of SPPs. The invention of graphene is a breakthrough in plasmon-based devices in terms of design, fabrication and applications, thanks to its plasmonic wave distribution,...
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Application of deep eutectic solvents in bioanalysis
PublicationThe application of deep eutectic solvents (DESs) is sharply surging as a green alternative to conventional solvents due to their unique properties in terms of simplicity of preparation, designability and low cost. A great deal of attention has been paid to the application of these green solvents in analytical chemistry in recent years, and a lot of interesting work has been reported. This review summarizes the most relevant applications...
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Latest Insights on Novel Deep Eutectic Solvents (DES) for Sustainable Extraction of Phenolic Compounds from Natural Sources
PublicationPhenolic compounds have long been of great importance in the pharmaceutical, food, and cosmetic industries. Unfortunately, conventional extraction procedures have a high cost and are time consuming, and the solvents used can represent a safety risk for operators, consumers, and the environment. Deep eutectic solvents (DESs) are green alternatives for extraction processes, given their low or non-toxicity, biodegradability, and reusability....
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A Generalized SDP Multi-Objective Optimization Method for EM-Based Microwave Device Design
PublicationIn 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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Composites of tin oxide and different carbonaceous materials as negative electrodes in lithium-ion batteries
PublicationAbstract Tin and tin oxide have been considered as suitable materials with high theoretical capacity for lithium ion batteries. Their low cost, high safety and other technical benefits placed them as promising replacements for graphite negative electrodes. The problem to overcome with tin oxide, as well as with other metallic materials, is high volume changes during alloying/dealloying, subsequent pulverization, delamination from...
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Bacteriophages as Factories for Eu2O3 Nanoparticle Synthesis
PublicationThe use of phage display to identify peptides with an ability to bind and synthesize Eu2O3 nanoparticles is demonstrated in this report. This is the first report of modified phages specifically binding a lanthanide. The peptides exposed on virions revealed very strong binding to Eu2O3 nanoparticles and the ability to catalyze Eu2O3 nanoparticles’ formation from Eu(OH)3 and Eu(NO3)3 solutions. The luminescence emission spectrum...
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System architecture of an INSPIRE-compliant green cadastre system for the EU Member State of Poland
PublicationIn response to the need for a sustainable agricultural policy, which would support activities such as decision making in precise agriculture and mitigation of crop threats, a concept agricultural information system was developed for the area of Poland. This innovative concept, called Green Cadastre (GC), proposes to create a uniform system designed for use on a national scale by both state administration as well as local farmers....
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FORECASTING EXCHANGE RATES IN THE PROCESS OF THE ASSESSMENT OF CONSUMER RISK BANKRUPTCY IN CENTRAL EUROPE
PublicationThis paper focuses on the issue of forecasting the fluctuation of exchange rates as part of the early warning system against the risk of consumer bankruptcy. The author identified the main macroeconomic factors affecting the level of bankruptcies for households in Poland. The fluctuation of exchange rates, which directly affects the deterioration of the economic situation of borrowers who have opened credit accounts in a foreign...
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Complex Predictive Solution for Computerized Processes in Tire Industry
PublicationFollowing increasing market needs of productivity, cost reduction and safety requirements, computerized industry are faced to finding optimum between economic aspects of business and safety-related risk management. Modern factories equipped with computerized processes and extended diagnostic tools to support operator do not often use of all information’s which comes from the equipment. Some of the relations between the events are...
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GSADF test results for national art market (G-7 group) + selected investments
Open Research DataThe dataset contains data illustrating the results of detecting and data-stamping price explosivity periods in national art markets in G-7 countries with additional investments from a second group (MSCI, S&P 500, crude oil, gold and silver). The files contain:• 01_diagnostics_gsadf – summary of results for analysed time series.• 02_st_value...
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Surface modifcation of PMMA polymer detected by XPS
Open Research DataIn order to obtain the experimental specimens, four PMMA/PC61BM samples with the following mass proportions were prepared: 10%, 20%, 30%, and 40%. In addition, as a reference, a PMMA sample without PC61BM was prepared as well. For the fabrication process, PC61BM 99.5% (Solenne BV), chloroform HPLC (Sigma Aldrich), and PMMA (commercially available...
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Knowledge-based performance-driven modeling of antenna structures
PublicationThe importance of surrogate modeling techniques in the design of modern antenna systems has been continuously growing over the recent years. This phenomenon is a matter of practical necessity rather than simply a fashion. On the one hand, antenna design procedures rely on full-wave electromagnetic (EM) simulation tools. On the other hand, the computational costs incurred by repetitive EM analyses involved in solving common tasks...
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High-Efficacy Global Optimization of Antenna Structures by Means of Simplex-Based Predictors
PublicationDesign of modern antenna systems has become highly dependent on computational tools, especially full-wave electromagnetic (EM) simulation models. EM analysis is capable of yielding accurate representation of antenna characteristics at the expense of considerable evaluation time. Consequently, execution of simulation-driven design procedures (optimization, statistical analysis, multi-criterial design) is severely hindered by the...
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Chapter 11 – Application of Chemical Sensors and Sensor Matrixes to Air Quality Evaluation
PublicationIndoor and outdoor air quality is one of the key factors influencing human health. However, air quality evaluation is not easy task. Air is a complex system, which is subjected to changes even within short period of time. Progress in analytical methods and analytical tools provides increasingly more reliable information on the condition and quality of indoor and outdoor air. This progress, however, generates an increase in the...
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Fast multi-objective optimization of antenna structures by means of data-driven surrogates and dimensionality reduction
PublicationDesign of contemporary antenna structures needs to account for several and often conflicting objectives. These are pertinent to both electrical and field properties of the antenna but also its geometry (e.g., footprint minimization). For practical reasons, especially to facilitate efficient optimization, single-objective formulations are most often employed, through either a priori preference articulation, objective aggregation,...
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Selektywne chłodzenie mózgu noworodka po niedotlenieniu okołoporodowym. Cześć 3. Hybrydowy system selektywnego chłodzenia mózgu noworodka
PublicationZapoczątkowane brakiem tlenu procesy biochemiczne mają zgubne skutki dla układu nerwowego, w szczególności rozwijającego się. Hipotermia, czyli stan oziębienia poniżej pewnych wartości temperatur, spowalnia znacznie lub całkowicie wyhamowuje poszczególne reakcje, i to leży u podstaw jej własności neuroprotekcyjnych. Powyższe twierdzenie poparte licznymi faktami naukowymi leży u podstaw koncepcji selektywnego chłodzenia mózgu i...
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Temperature Sensors Based on Polymer Fiber Optic Interferometer
PublicationTemperature measurements are of great importance in many fields of human activities, including industry, technology, and science. For example, obtaining a certain temperature value or a sudden change in it can be the primary control marker of a chemical process. Fiber optic sensors have remarkable properties giving a broad range of applications. They enable continuous real-time temperature control in difficult-to-reach areas, in...
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The EU enlargement and domestic employment
PublicationThe study focuses on the interactions between EU member states' labor markets (manufacturing and tradable business services) over the period 1995-2005. We use recently released detailed sector level employment statistics, considering the effects of trade integration on the creation of links between labor force in ''Old'' and ''New'' partners in the enlarged EU. Empirical estimations show that the domestic demand for labor in the...
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Molecularly imprinted polymers based on deep eutectic solvents as a greenest materials for selective extraction of emerging contaminants from complex samples
PublicationSome of the reagents applied in the synthesis of molecularly imprinted polymers (MIPs) may impact on health and the environment. Thus, a new generation of promising green chemicals are nowadays introduced and investigated, including deep eutectic solvents (DESs). DESs seems to be a reasonable choice as they are characterized as non-toxic, low cost, easy to prepare and biodegradable chemicals. This review presents the information...
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Single-phase power electronics transformer with active functions for smart grid
PublicationThis paper presents the control of one cell of a modular single-phase power electronics transformer with active functions for meeting the smart grid concept. In this way, the converter could be used not only as a conventional transformer but also for grid such as reactive power, harmonic elimination and energy storage. The topology of the cell is composed by a bidirectional converter with three stages: a half bridge in the input...
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Guided waves for monitoring of plate structures with linear cracks of variable length
PublicationDamage occurring at the work of plate structures may grow to a considerable size. The joint action – the detection of a defect at the earliest possible stage, the monitoring of its growth and the determination of its critical size in the context of structural reliability allows optimizing the cost of the maintenance and repair of structural elements. Thus the development of monitoring systems for permanent observation of fault...
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3D porous graphene-based structures- synthesis and applications
PublicationPorous carbon-based materials are of the great industrial and academic interest due to their high surface area, low density, good electrical conductivity, chemical inertness and low cost of fabrication. Up to now, the main approach to obtain porous carbon structures has involved the pyrolysis of carbonaceous natural or synthetic precursors. After the isolation of graphene, the interest in 3D porous graphene-based structures (called...
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Optimization of Graphene Oxide Synthesis and Its Reduction
PublicationIn this article, we present the review of the chemical methods of synthesis of graphene oxide and its reduction in order to obtain the so-called reduced graphene oxide (rGO) whose properties are similar to those of pure graphene. We also present our experiments and the results in this field and the comparison of the efficiency of different methods of synthesis as well as the reduction of graphene oxide. To characterize the obtained...
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Efficient Multi-Objective Simulation-Driven Antenna Design Using Co-Kriging
PublicationA methodology for fast multi-objective antenna optimization is presented. Our approach is based on response surface approximation (RSA) modeling and variable-fidelity electromagnetic (EM) simulations. In the design process, a computationally cheap RSA surrogate model constructed from sampled coarse-discretization EM antenna simulations is optimized using a multi-objective evolutionary algorithm. The initially determined Pareto...
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Simulation-Based Design of Microstrip Linear Antenna Arrays Using Fast Radiation Response Surrogates
PublicationFast yet accurate technique for simulation-based design of linear arrays of microstrip patch antennas is presented. Our technique includes: (i) optimization of the corrected array factor of the antenna array under design for a phase excitation taper resulting in reduced side lobes; (ii) simulation-driven optimization of the array element for element dimensions resulting in matching at and about operational frequency, and (iii)...
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Analogue CMOS ASICs in Image Processing Systems
PublicationIn this paper a survey of analog application specific integrated circuits (ASICs) for low-level image processing, called vision chips, is presented. Due to the specific requirements, the vision chips are designed using different architectures best suited to their functions. The main types of the vision chip architectures and their properties are presented and characterized on selected examples of prototype integrated circuits (ICs)...
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Fast surrogate-assisted simulation-driven design of compact microwave hybrid couplers
PublicationThis work presents a robust methodology for expedited simulation-driven design optimization of compact microwave hybrid couplers. The technique relies on problem decomposition, and a bot-tom–up design strategy, starting from the level of basic building blocks of the coupler, and finishing with a tuning procedure that exploits a fast surrogate model of the entire structure. The latter is constructed by cascading local response surface...
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Dynamic soil improvement by hybrid technologies
PublicationHybrid method of subsoil improvement for road embankment foundation is described. This method is composed of two wellknown methods: dynamic replacement (DR) and microblasting (DDC) one (Deep Dynamic Compaction). The method was used for both the strengthening of the fully saturated organic subsoil as well as for acceleration of the consolidation of the organic layers. The practice ensures the expected results. A proper example on...