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Search results for: conventional pid controller
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Compact 4 × 4 butler matrix with non‐standard phase differences for IoT applications
PublicationButler matrices represent a popular class of feeding networks for antenna arrays. Large dimensions and the lack of flexibility in terms of achievable output phase difference make conventional Butler structures of limited use for modern communication devices. In this work, a compact planar 4 × 4 matrix with non-standard relative phase shifts of –30º, 150º, –120º, and 60º has been proposed. The structure is designed to operate at...
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Isocyanate-Free Polyurethanes
PublicationIsocyanate-free polyurethanes (also called non-isocyanate polyurethanes, or NIPUs) are alternatives to the conventional (commercially used) polyurethanes synthesized using di- or polyisocyanates, polyols, and chain extenders with low molecular weight. The major routes of NIPUs’ synthesis involve polyaddition of cyclic carbonates and di- or polyamines, polycondensation of carbamates, and diols. The most important intermediates are...
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A Direct Modulation for Matrix Converters based on the Onecycle Atomic operation developed in Verilog HDL.
PublicationThis paper presents a fast direct Pulse Width Modulation (PWM) algorithm for the Conventional Matrix Converters (CMC) developed in Verilog Hardware Description language (HDL). All PWM duty cycle calculations are performed in one cycle by an atomic operation designed as a digital module using FPGA basic blocks. The algorithm can be extended to any number of output phase. The improved version of the discontinuous Direct Analytic...
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Surfactants application in sample preparation techniques: Insights, trends, and perspectives
PublicationSince the implementation of Green Chemistry into analytical practice, significant efforts have been made to improve the sustainability of chemical analysis. These include reducing the use of hazardous chemicals and solvents, minimizing waste, and improving energy efficiency. Surfactants can be applied in chemical analysis as an environmentally friendly alternative to conventional solvents and chemicals. The use of surfactants can...
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Bending and buckling formulation of graphene sheets based on nonlocal simple first-order shear deformation theory
PublicationThis paper presents a formulation based on simple first-order shear deformation theory (S-FSDT) for large deflection and buckling of orthotropic single-layered graphene sheets (SLGSs). The S-FSDT has many advantages compared to the classical plate theory (CPT) and conventional FSDT such as needless of shear correction factor, containing less number of unknowns than the existing FSDT and strong similarities with the CPT. Governing...
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Nanoparticles: Synthesis, characteristics, and applications in analytical and other sciences
PublicationNanoparticles (NPs) are widely employed in different research areas, ranging from analytical chemistry and environmental science to medicine, the agriculture and pharmaceutical industry. This is mainly due to the unique characteristics of NPs and the novelty they introduce in such applications. In analytical chemistry, the role of NPs can differ depending on the nature of the steps involved in analytical process. NPs are probably...
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Influence of anisotropic stiffness in numerical analyses of tunneling and excavation problems in stiff soils
PublicationIn the stiff overconsolidated soil deposits anisotropy influences small and intermediate strain stiffness and hence it has important impact on the results of discplacement preditcions in soil-structure modelling. The authors developed a cross-anisotropic soil model which combines both stress dependent and micro-structural anisotropy. The model is based on the anisotropic hyperelastic kernel for small strain stiffness. Reference...
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Robust Model Predictive Control for Autonomous Underwater Vehicle – Manipulator System with Fuzzy Compensator
PublicationThis paper proposes an improved Model Predictive Control (MPC) approach including a fuzzy compensator in order to track desired trajectories of autonomous Underwater Vehicle Manipulator Systems (UVMS). The tracking performance can be affected by robot dynamical model uncertainties and applied external disturbances. Nevertheless, the MPC as a known proficient nonlinear control approach should be improved by the uncertainty estimator...
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Removal of Pharmaceutically Active Compounds in Sequencing Batch Reactor
PublicationIn recent years, considerable attention was paid to the presence of organic micro-pollutants such as Active Pharmaceutical Ingredients (API) in the aquatic environment due to their negative impact on public health and aquatic ecosystems. Numerous papers have pointed out API presence as common constituents of effluents from Wastewater Treatment Plants (WWTPs). This is the result of various efficiencies of API removal by conventional...
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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...
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Influence of passive house technology on time and cost of construction investment
PublicationDue to the changes in the energy standards for housing in Poland there are many concerns. Is the standard required by the regulation achievable and if it is, then at what cost? There are many solutions to construct a building in line with the requirements of passive house technology. They are differentiated by price and time required for implementation. This study is based on the solution proposed by one of Polish companies, offering...
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A New Approach for the Mitigating of Flow Maldistribution in Parallel Microchannel Heat Sink
PublicationThe problem of flow maldistribution is very critical in microchannel heat sinks (MCHS). It induces temperature nonuniformity, which may ultimately lead to the breakdown of associated system. In the present communication, a novel approach for the mitigation of flow maldistribution problem in parallel MCHS has been proposed using variable width microchannels. Numerical simulation of copper made parallel MCHS consisting of 25 channels...
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Synthesis Methods and Favorable Conditions for Spherical Vaterite Precipitation: A Review
PublicationVaterite is the least thermodynamically stable anhydrous calcium carbonate polymorph. It exists very rare in nature, e.g. in some rock formations or as a component of biominerals produced by some fishes, crustaceans or birds. Synthetic vaterite particles are proposed as carriers of active substances in medicines, additive in cosmetic preparations as well as adsorbents. Also, their utilization as a pump for microfluidic flow is...
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NEW DESIGNS OF CENTRIFUGAL MAGNETIC FLUID SEALS FOR ROTATING SHAFTS IN MARINE TECHNOLOGY
PublicationThe centrifugal magnetic fluid seals have important advantage over the conventional centrifugal seals. They maintain very good sealing capacity at static, medium and high speeds of shaft rotation, with the increased seal lifetime, and minimum torque and static friction. These seals are particularly useful in cases when the angular shaft velocity varies and sometimes decreases to nearly or exactly zero, such as in flywheel applications,...
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Reliable low-cost surrogate modeling and design optimisation of antennas using implicit space mapping with substrate segmentation
PublicationAbstract: In this work, a reliable methodology for fast simulation-driven design optimisation of antenna structures is proposed. The authors’ approach exploits implicit space mapping (ISM) technology. To adopt it for handling antenna structures, they introduce substrate segmentation with separate dielectric permittivity value assigned for each segment as ISM preassigned parameters. At the same time, the coarse model for space mapping...
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Comparative study of operation of condensing and traditional boilers equipped with the ORC module for electricity generation
PublicationCondensing technology applied to boilers is to make full use of thermal energy contained in the fuel. That means that additionaly the heat from condensation of exhaust gases can be used for the purposes of heating the domestic hot water and to cover the demand for central heating. The study analyzed the operation of the "traditional" boiler equipped with the ORC module as the similar arrangement but with the condensing boiler....
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The effect of UV-C irradiation on lipids and selected biologically active compounds in human milk
PublicationThe effect of UV-C irradiation of human milk on lipid oxidation, content of antioxidants (vitamin C and catalase, CAT) and bactericidal compounds (lysozyme), as well as the total antioxidant capacity (TAC), of the breast milk was investigated. In parallel, the extent of inactivation of some bacteria was also determined. UV-C at doses from 85 to 740 J L−1 caused total inactivation of Escherichia coli and Staphylococcus aureus, but...
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Electronic structure and magnetism of samarium and neodymium adatoms on free-standing graphene
PublicationThe electronic structure of selected rare-earth atoms adsorbed on a free-standing graphene was investigated using methods beyond the conventional density functional theory (DFT+U, DFT +HIA, and DFT+ED). The influence of the electron correlations and the spin-orbit coupling on the magnetic properties has been examined. The DFT+U method predicts both atoms to carry local magnetic moments (spin and orbital) contrary to a nonmagnetic...
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Microstructure of barium-vanadate glasses
Open Research DataThe structure of barium-vanadate glasses was measured by SEM and XRD techniques. Samples of the composition of xBaO-(100-x)V2O5 where x= 30, 40 and 45 (in %mol) were prepared by the conventional melt quenching technique. Appropriate amounts of reagents: BaO (≥99.9%, P.P.H STANLAB Sp.J.) and V2O5 (≥99.9%, POCH) were thoroughly mixed in an agate mortar....
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Linear impedance of 10Na2O–60P2O5–30CaO glass measured with impedance spectroscopy method at low temperature region
Open Research DataThe linear electrical properties of 10Na2O–60P2O5–30CaO glass was measured by impedance spectroscopy method.
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Calculations of the resistance values of 20 thermistors at 0°C
Open Research DataThe presented data set is part of the research aimed at determining the actual characteristics of each thermistor in a package of twenty NTC10k type sensors.
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Bezpieczeństwo funkcjonalne i ochrona informacji w obiektach i systemach infrastruktury krytycznej - analiza i ocena
PublicationW niniejszym rozdziale monografii przedstawiono bardzo aktualną problematykę związaną z analizą bezpieczeństwa funkcjonalnego rozproszonych systemów sterowania i automatyki zabezpieczeniowej w obiektach infrastruktury krytycznej, wykorzystujących przemysłową sieć komputerową, z uwzględnieniem zagadnień ochrony informacji. W obiektach tego typu systemy sterowania i automatyki zabezpieczeniowej są projektowane jako systemy rozproszone,...
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Method of selective fading as a educational tool to study the behaviour of prestressed concrete elements under excess loading
PublicationPrestressed structures are a key to realization of the boldest architectural ideas, characteristic feature of prestressed structure is better use of concrete material properties by insertion of internal forces. Learning about pre-stressed reinforced concrete structures is an integral part of Graduate Studies Program in construction engineering. Know-how of geometry change patterns in prestressed concrete elements under certain...
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State-of-the-art framework for high-speed camera and photogrammetric use in geometry evaluation of prestressed concrete failure process
PublicationPrestressed structures are a key to the realization of the boldest architectural ideas, regardless of shape complexity, great height and large span. A characteristic feature of the prestressed structure is the better use of concrete material properties by insertion of internal forces. The internal forces are opposed to external loads effects (forces and deformations of structure). Prestressed reinforced concrete beams are characterized...
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Multifrequency Wideband Sonar Array
PublicationThis paper describes of new approach to Multifrequency Wideband Arrays (MWA),applied piezocomposite technologies of the array elements. MWA operating in transmitting(Tx) and receiving (Rx) mode on two or three bands, requires state-of-the-art technology andefficient array designing than conventional array in which separate arrays for every band oreven separate Tx and Rx transducers/arrays are used. The new piezocomposite elements...
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Application of atmospheric pressure microwave plasma source for hydrogen production from ethanol
PublicationIn contrast to conventional technologies of hydrogen production like water electrolysis or coal gasification we propose a method based on the atmospheric pressure microwave plasma. In this paper we present results of the experimental investigations of the hydrogen production from ethanol in the atmospheric pressure plasma generated in waveguidesupplied cylindrical type nozzleless microwave (915 MHz and 2.45 GHz) plasma source (MPS)....
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The quality of sewage sludge stabilized for a long time in reed basins
PublicationThe aim of the work was to determine changes of long-term sewage sludge quality stabilized in reed basins from 7-15 years. The following parameters were evaluated: dry matter and organic matter concentration, nitrogen, phosphorus, and selected heavy metal (Cd, Ni, Pb, Cr, Cu, Zn) fractions. The material for the investigations was collected from 4 reed basin systems (utilisated sewage sludge) located in conventional WWTPs in Denmark...
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Respiratory system modelling and simulation basing on the forced oscilation technique
PublicationConventional methods of testing lung functioning demand a specific respiratory action of the patient. In contrast, the forced oscillation technique (fot) provides measurements obtained with a minimal cooperation of the subject. The aim of this study is to verify the usefulness of the forced oscillation technique modelling in respiratory system diagnosing. in order to do it two models of fot measurements have been considered: the...
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Novel sorptive extraction techniques in bioanalysis evaluated by Blue Applicability Grade Index: The paradigm of fabric phase sorptive extraction and capsule phase microextraction
PublicationFabric phase sorptive extraction (FPSE) and capsule phase microextraction (CPME) are two sol-gel derived microextraction techniques that emerged in the last decade towards the minimization of the environmental impact of conventional sample preparation approaches. Complementary to the well-established green metric tools, Blue Applicability Grade Index (BAGI) was recently proposed for the evaluation of method’s practicability. In...
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Inorganic membrane: a game changer for gas separation and purification
PublicationThis review explores the advancements and remaining challenges in inorganic membrane science, particularly focusing on their potential for industrial applications. It delves into the fundamental principles of inorganic membrane design, fabrication, and characterization techniques. The review also critically analyzes key challenges faced by inorganic membranes, such as physical aging, plasticization, defective formation, and fouling....
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Nitrogen oxides removal from hydrogen flue gas using corona discharge in marine boilers: Application perspective
PublicationThis paper focuses on the combustion of hydrogen in boilers, as it appears to be a more effective method than using fuel cells for heating purposes due to higher boiler efficiency. One of the main disadvantages of hydrogen combustion in air is NOx formation. Therefore, the authors decided to introduce corona discharge as an inno- vative technique to clean hydrogen flue gas by effectively reducing NOx levels. The method involves...
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Low-cost multi-objective design of compact microwave structures using domain patching
PublicationA 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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Simultaneous determination of Na+, K+, Ca2+, Mg2+ and Cl- in unstimulated and stimulated human saliva using all solid state multisensor platform
PublicationHuman saliva is one of the body fluids which collection method is relatively simple and non-invasive. The article is dedicated to assess concentration (activity) of Na+, K+, Ca2+, Mg2+ and Cl- in fresh, unstimulated or stimulated human saliva samples using single solid contact ion-selective electrodes with conventional reference electrode and self-made multisensor platform (MP) equipped with ion-selective membranes for Na+, K+,...
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Direct Analysis of Samples of Various Origin and Composition Using Specific Types of Mass Spectrometry
PublicationOne of the major sources of error that occur during chemical analysis utilizing the more conventional and established analytical techniques is the possibility of losing part of the analytes during the sample preparation stage. Unfortunately, this sample preparation stage is required to improve analytical sensitivity and precision. Direct techniques have helped to shorten or even bypass the sample preparation stage; and in this...
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Shielded HMSIW-Based Self-Triplexing Antenna With High Isolation for WiFi/WLAN/ISM Band
PublicationThis article presents a novel design of a miniaturized self-triplexing antenna (STA) based on the shielded half-mode substrate integrated waveguide (S-HMSIW) for WiFi/WLAN/ISM-band applications. The S-HMSIW is constructed by assembling one row of vias and an open slot at the open-ended side of the conventional HMSIW. This configuration increases the quality factor and minimizes unwanted radiation loss, which allows for achieving...
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Frequency-Based Regularization for Improved Reliability Optimization of Antenna Structures
PublicationThe paper proposes a modified formulation of antenna parameter tuning problem. The main ingredient of the presented approach is a frequency-based regularization. It allows for smoothening the functional landscape of the assumed cost function, defined to encode the prescribed design specifications. The regularization is implemented as a special penalty term complementing the primary objective and enforcing the alignment of the antenna...
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Evaluation and start-up of an electro-Fenton-sequencing batch reactor for dairy wastewater treatment
PublicationThis study examined the performance of an integrated wastewater (WW) treatment system, namely an electro-Fenton (EF)-sequencing batch reactor (SBR), for dairy industry WW. The EF process was used as the first stage of the SBR. It degrades bio-refractory compounds via advanced oxidation processes, thereby resulting in the formation of simple biodegradable intermediates. Several factors, including the hydraulic retention time (HRT),...
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Robust-adaptive dynamic programming-based time-delay control of autonomous ships under stochastic disturbances using an actor-critic learning algorithm
PublicationThis paper proposes a hybrid robust-adaptive learning-based control scheme based on Approximate Dynamic Programming (ADP) for the tracking control of autonomous ship maneuvering. We adopt a Time-Delay Control (TDC) approach, which is known as a simple, practical, model free and roughly robust strategy, combined with an Actor-Critic Approximate Dynamic Programming (ACADP) algorithm as an adaptive part in the proposed hybrid control...
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The effect of beech wood (Fagus sylvatica L.) steaming process on the colour change versus depth of tested wood layer
PublicationThe results of experimental research on the colour changes of beech wood at different depths of the tested layer are presented. Beech wood (Fagus sylvatica L.) dried in a conventional kiln was tested. Half of the wood samples were steamed prior to the drying process. Colour changes were measured at various depths after the face milling process was used to remove the material to expose to the deeper surface. The colour changes were...
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Studies on the use of terrestrial laser scanning in the maintenance of buildings belonging to the cultural heritage
PublicationWithin the frames of the use of terrestrial laser scanning we find numerous examples of registration of building facilities, including also historical and valuable in their culture. In the case presented in this paper, at the root of the problem there is a preservation of the historic blacksmith's forge located in Gdansk Orunia. The facility dating from the early nineteenth century was intended to repair involving the complete...
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Stress-driven nonlocal elasticity for nonlinear vibration characteristics of carbon/boron-nitride hetero-nanotube subject to magneto-thermal environment
PublicationStress-driven nonlocal theory of elasticity, in its differential form, is applied to investigate the nonlinear vibrational characteristics of a hetero-nanotube in magneto-thermal environment with the help of finite element method. In order to more precisely deal with the dynamic behavior of size-dependent nanotubes, a two-node beam element with six degrees-of freedom including the nodal values of the deflection, slope and curvature...
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NbIr 2 B 2 and TaIr 2 B 2 – New Low Symmetry Noncentrosymmetric Superconductors with Strong Spin–Orbit Coupling
PublicationSuperconductivity was first observed more than a century ago, but the search for new superconducting materials remains a challenge. The Cooper pairs in superconductors are ideal embodiments of quantum entanglement. Thus, novel superconductors can be critical for both learning about electronic systems in condensed matter and for possible application in future quantum technologies. Here two previously unreported materials, NbIr2B2...
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Mössbauer Spectroscopy and Magnetoelectric Effect Studies of Multiferroic Ceramics Based on BiFeO<sub>3</sub>
PublicationIn this work the results of investigations for (BiFeO3)x(BaTiO3)1-x and Bi1-xNdxFeO3 solid solutions are described. Samples were prepared by the conventional solid-state sintering method. X-ray diffraction, 57Fe Mössbauer spectroscopy, and magnetoelectric effect measurements were applied as complementary methods to determine the structure and magnetic properties of materials. For (BiFeO3)x(BaTiO3)1-x solid solutions Mössbauer...
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Surrogate Modeling and Optimization Using Shape-Preserving Response Prediction: A Review
PublicationComputer simulation models are ubiquitous in modern engineering design. In many cases, they are the only way to evaluate a given design with sufficient fidelity. Unfortunately, an added computa-tional expense is associated with higher fidelity models. Moreover, the systems being considered are often highly nonlinear and may feature a large number of designable parameters. Therefore, it may be impractical to solve the design problem...
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Accelerated simulation-driven design optimisation of compact couplers by means of two-level space mapping
PublicationIn this study, the authors discuss a robust and efficient technique for rapid design of compact couplers. The approach exploits two-level space mapping (SM) correction of an equivalent circuit model of the coupler structure under design. The first SM layer (local correction) is utilised to ensure good matching between the equivalent circuit and the electromagnetic model at the component level. Subsequent global correction allows...
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STUDIES ON THE USE OF TERRESTRIAL LASER SCANNING IN THE MAINTENANCE OF BUILDINGS BELONGING TO THE CULTURAL HERITAGE
PublicationWithin the frames of the use of terrestrial laser scanning we find numerous examples of registration of building facilities, including also historical and valuable in their culture. In the case presented in this paper, at the root of the problem there is a preservation of the historic blacksmith’s forge located in Gdansk Orunia. The facility dating from the early nineteenth century was intended to repair involving the complete...
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Statistical analysis and robust design of circularly polarized antennas using sequential approximate optimization
PublicationIn 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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Multi-objective design optimization of antennas for reflection, size, and gain variability using kriging surrogates and generalized domain segmentation
PublicationCost-efficient multi-objective design optimization of antennas is presented. The framework exploits auxiliary data-driven surrogates, a multi-objective evolutionary algorithm for initial Pareto front identification, response correction techniques for design refinement, as well as generalized domain segmentation. The purpose of this last mechanism is to reduce the volume of the design space region that needs to be sampled in order...
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Selected Aspects of Biofuels Market and the Electromobility Development in Poland: Current Trends and Forecasting Changes
PublicationThis work presents basic information associated with markets of selected alternative fuels used in transport, such as methyl esters, conventional bioethanol and lignocellulosic bioethanol, and the market of electrical vehicles. Legal conditions, which stimulate development and regulate the mode of functioning of the liquid biofuel market until 2020 are discussed, based on provisions of EU directives. Data on biofuel production...
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Influence of reactive oxygen species during deposition of iron oxide films by high power impulse magnetron sputtering.
PublicationIron oxide films were deposited using high power impulse magnetron sputtering (HiPIMS) of an iron cathode in an argon/oxygen gas mixture at different gas pressures (0.5~Pa, 1.5~Pa, and 5.0~Pa). The HiPIMS system was operated at a repetition frequency $f = 100$~Hz with a duty cycle of 1~\%. A main goal is a comparison of film growth during conventional and electron cyclotron wave resonance-assisted HiPIMS. The deposition plasma...