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Assessment of Citizens’ Actions against Light Pollution with Guidelines for Future Initiatives
PublicationDue to the wide reach of media reports about scientific research and technological tools such as the world wide web (WWW), the Internet, and web browsers, citizens today have access to factual information about the negative impact of artificial light at night (ALAN) on their dark skies, and their health and well-being. This means they can now make educated decisions and take the necessary steps to help protect themselves and their...
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A novel concept of negative CO2 emission power plant for utilization of sewage sludge
PublicationCarbon Capture and Storage (CSS) technology is considered an important “bridge technology”, allowing effective abatement of CO2 emissions for power units using fossil fuels. However, if biomass is used in a power plant, equipped with CCS system, negative CO2 emissions can be achieved. In practice, wide development of such technologies would enable not only reduction of CO2 emissions, but also reversal of the harm done so far. In...
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Model Management for Low-Computational-Budget Simulation-Based Optimization of Antenna Structures Using Nature-Inspired Algorithms
PublicationThe primary objective of this study is investigation of the possibilities of accelerating nature-inspired optimization of antenna structures using multi-fidelity EM simulation models. The primary methodology developed to achieve acceleration is a model management scheme which the level of EM simulation fidelity using two criteria: the convergence status of the optimization algorithm, and relative quality of the individual designs...
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High frequency impulse ground penetrating radar application in assessment of interlayer connections
PublicationGround Penetrating Radar (GPR) technique is commonly used in the nondestructive evaluation of pavement structures. In particular, this method is used to estimate thicknesses of pavement layers as well as it can be utilized in advanced studies of pavement structures. The device presented in this paper comprise the high frequency impulse antennas that allow for investigating the interlayer zones in terms of their electromagnetic...
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Generalized Pareto ranking bisection for computationally feasible multi-objective antenna optimization
PublicationMulti-objective optimization (MO) allows for obtaining comprehensive information about possible design trade-offs of a given antenna structure. Yet, executing MO using the most popular class of techniques, population-based metaheuristics, may be computationally prohibitive when full-wave EM analysis is utilized for antenna evaluation. In this work, a low-cost and fully deterministic MO methodology is introduced. The proposed generalized...
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Simulation-driven design of compact ultra-wideband antenna structures
PublicationPurpose–The purpose of this paper is to investigate strategies and algorithms for expedited designoptimization and explicit size reduction of compact ultra-wideband (UWB) antennas.Design/methodology/approach–Formulation of the compact antenna design problem aiming atexplicit size reduction while maintaining acceptable electrical performance is presented. Algorithmicframeworks are described suitable for handling various design situations...
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Multi-objective design optimization of antenna structures using sequential domain patching with automated patch size deter-mination
PublicationIn this paper, a simple yet efficient and reliable technique for fully automated multi-objective design optimization of antenna structures using sequential domain patching (SDP) is discussed. The optimization procedure according to SDP is a two-step process: (i) obtaining the initial set of Pareto-optimal designs representing the best possible trade-offs between considered conflicting objectives, and (ii) Pareto set refinement...
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Rapid Multi-Criterial Antenna Optimization by Means of Pareto Front Triangulation and Interpolative Design Predictors
PublicationModern antenna systems are designed to meet stringent performance requirements pertinent to both their electrical and field properties. The objectives typically stay in conflict with each other. As the simultaneous improvement of all performance parameters is rarely possible, compromise solutions have to be sought. The most comprehensive information about available design trade-offs can be obtained through multi-objective optimization...
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Regionalna strategia w obszarze polityki rynku pracy w województwie pomorskim
PublicationCelem artykułu jest przedstawienie strategii i planów działań w obszarze rynku pracy przygotowanych przez władze samorządowe województwa pomorskiego.. Władze regionalne i lokalne województwa pomorskiego opracowały szereg dokumentów wytyczających główne kierunki polityki rynku pracy. Najważniejsze z nich to „Strategia rozwoju województwa pomorskiego do roku 2020” oraz „Regionalny Plan Działań na Rzecz Zatrudnienia dla województwa...
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Global Trends 2022
e-Learning CoursesThe course reflects on the different models of capitalism, starting with the debate on "Varieties of capitalism". It will deal with the relationships between historical dimension, juridical and economic cultures, institutions, financial markets and ownership structures in today's world economy. The aim of the course is trying to give an answer to a couple of very simple questions: why economic systems react in a different way...
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Adaptive prediction of stock exchange indices by state space wavelet networks
PublicationThe paper considers the forecasting of the Warsaw Stock Exchange price index WIG20 by applying a state space wavelet network model of the index price. The approach can be applied to the development of tools for predicting changes of other economic indicators, especially stock exchange indices. The paper presents a general state space wavelet network model and the underlying principles. The model is applied to produce one session...
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A study of concentration depolarization and quenching of photoluminescence of solutions
PublicationThe concentration-dependence of emission anisotropy r/r0 and quantum yield eta/eta0 of the photoluminescence of glycerol-water solutions of rhodamine B in two systems of viscosities 7.4 P and 0.72 P is investigated. The experimental data are compared with the new theory of concentraticn depolarization (J. Lumin., 5, 413 (1972)) and concentration quenching of photoluminescence (Acta Phys. Hungar., 30, 145 (1972)), which takes...
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Conducted emi propagation modelling in the wound components.
PublicationThe modelling of EMC behaviour of power electronics converters require specific models of devices which are adequate in a wide frequency range. A novel equivalent-circuit model of the inductor, suitable for EMC applications, has been developed and validated. The model can be used for the analyses of wounded components' behaviour in the conducted-EMI frequency range. The parameters of the proposed model can be evaluated based on...
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Sensorless IPMSM drive with rotor position estimator based on analysis of phase current derivatives
PublicationThis paper describes a sensorless Interior Permanent Magnet Synchronous Motor (IPMSM) drive designed for traction applications. Wide-speed sensorless operation is provided with the use of three methods of rotor position estimation designed for: a standstill, low- and high-speed range. The paper focuses on the high-speed estimation algorithm. The estimator uses the derivatives of motor phase currentsresulting from PWM modulation...
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Physical and Thermophysical Properties of 1-Hexyl-1,4-diaza[2.2.2]bicyclooctanium Bis(trifluoromethylsulfonyl)imide Ionic Liquid
PublicationOwing to their unique properties, ionic liquids (ILs) have become a real alternative to organic compounds. Nowadays, ILs are commonly used in a number of areas such as chemical synthesis and separation techniques. However, ionic liquids continue to have a limited applicability in industry because the information on their physical and chemical properties is not readily available. This paper presents, for the first time, the results...
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HYDRODYNAMIC THRUST BEARINGS WITH POLYMER LINING
PublicationPolymeric linings of sliding surfaces of the hydrodynamic bearings have been used successfully for over 50 years. Despite of their long history of operation and research, they have not become wide spread in industrial applications. This fact may be surprising, considering th e conclusions that have been published concerning bearing operation and design. This paper summarizes the current...
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Nonlinear Viscoelastic Properties of Polyurethane Nanocomposites
PublicationIn recent years, the nonlinear viscoelastic behaviors of elastomeric nanocomposites have been examined, especially for a wide range of rubbery composite (including natural rubber) materials. This chapter describes the influence of fillers and nanofillers on the nonlinear viscoelastic properties of elastomeric polyurethane systems. These filled elastomers (similar to the classic natural rubber reinforced elastomers), also exhibit...
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Identification and non-integer order modelling of synchronous machines operating as generator
PublicationThis paper presents an original mathematical model of a synchronous generator using derivatives of fractional order. In contrast to classical models composed of a large number of R-L ladders, it comprises half-order impedances, which enable the accurate description of the electromagnetic induction phenomena in a wide frequency range, while minimizing the order and number of model parameters. The proposed model takes into account...
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On the necessity of experimental verification of numerical results in biomedical applications
PublicationPorous structures made of metal or biopolymers with a structure similar in shape and mechanical properties to human bone can be easily produced by stereolitography techniques, e.g. selective laser melting (SLM). Numerical techniques, like finite element method (FEM) have great potential in testing new, even the most sophisticated designs, according to their mechanical properties, i.e. strength or stiffness. However, due to different...
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Performance of a hybrid microjet – microchannel cooling module
PublicationThe paper presents the experimental investigation of a microjet- microchannel cooling module. In which microjets of water are impinging into the microchannels and forming a liquid film on the impingement surface. Applied technology takes benefits from two very attractive heat removal techniques. When lminar jets are impinging on the surface have a very high kinetic energy at the stagnation point, also in microchannels boundary...
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Badania bioaktywności z wykorzystaniem komórek kościotwórczych na tytanie pokrytym chitozanem = Bioactivity studies using osteogenic cells on titanium coated with chitosan
PublicationChitosan is a natural polymer from the group of polysaccharides, which has found wide application in biomedical applications to induce bioactivity of implant. The studies described were carried out test imposition of chitosan membranes with varying degrees of deacetylation on the surface of titanium, and then check the bioactivity of the material in vitro, using osteogenic cells MC3T3-E1. Titanium surface before imposition of...
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Miniaturized Solid Phase Extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 1
PublicationSolid Phase Extraction (SPE) has been practiced in a modern form for more than half a century. It was constantly developing, driven by the analysts needs. These needs are coming from the importance to select an appropriate analytical method, which should have satisfactory accuracy, precision and sensitivity. In the case of sorbent-based microextraction techniques, the choice of miniaturized variants that meet these requirements...
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A method to synthesise groove cam Geneva mechanisms with increased dwell period
PublicationThe present study develops a method to synthesise the groove cam Geneva mechanism with increased dwell period. The main condition of the synthesis is to provide the desired law of motion of the wheel. Additional synthesis conditions are the limitation of the maximum pressure angle and the limitation of the minimum curvature radius of the cam profile. Unlike the conventional Geneva mechanisms, the synthesised groove cam Geneva mechanisms...
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Greening procedures and analytical parameters. The polychlorinated naphthalenes analysis in complex matrices as proof of concept
PublicationDue to the complexity of analytical procedures employed for the determination of wide spectrum of persistent organic pollutants (POPs), it is important to consider the green character of the applied protocols and propose the greenest solutions. In this review, the green aspects of several analytical procedures used for the determination of polychlorinated naphthalenes (PCNs) (as a representatives of POPs) in different types of...
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Analysis of Properties of an Active Linear Gesture Sensor
PublicationBasic gesture sensors can play a significant role as input units in mobile smart devices. However, they have to handle a wide variety of gestures while preserving the advantages of basic sensors. In this paper a user-determined approach to the design of a sparse optical gesture sensor is proposed. The statistical research on a study group of individuals includes the measurement of user-related parameters like the speed of a performed...
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Computing methods for fast and precise body surface area estimation of selected body parts
PublicationCurrently used body surface area (BSA) formulas give satisfactory results only for individuals with typical physique, while for elderly, obese or anorectic people accurate results cannot be expected. Particularly noteworthy are the results for individuals with severe obesity (body-mass index greater than 35 kg/m2), for which BSA estimation errors reached 80%. The main goal of our study is the development of precise BSA models for...
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Asynchronous WAM with Irregular Pulse Repetition
PublicationRadiolocation systems for aviation based on Multi-Lateration (MLAT) typically use a set of synchronised ground sensors to receive radio signals broadcast by onboard transmitters. In most cases, the sensor synchronisation in Wide Area Multi-Lateration Systems (WAM) is provided by Global Navigation Satellite System (GNSS) receivers. However, in the case of synchronisation failure, there is still a possibility to estimate the coordinates...
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Superconductivity in the superhard boride WB4.2
PublicationWe show that the superhard boride WB4.2 is a superconductor with a Tc of 2.05(5) K. Temperature-dependent magnetic susceptibility, electrical resistivity, and specific heat measurements were used to characterize the superconducting transition. The Sommerfeld constant γ for WB4.2 is 2.07(3) mJ mol−1 K−2 and the ΔC/γTc=1.56, which is somewhat higher than what is expected for weakly coupled Bardeen–Cooper–Schrieffer type superconductors....
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Prospects in elongation of railway transition curves
PublicationThe paper presents an analysis of the elongation of transition curves in relation to railway track alignment correction and modernisation. The analysis is based on numerical computations for a wide range of parameters describing a typical railway geometrical layout with transition curves. The differences between the horizontal ordinates of the existing layout and the layout with the elongated transition curves are evaluated and...
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The study of Arduino Uno feasibility for DAQ purposes
PublicationUsing microcontroller systems becomes a routine in various measurement and control tasks. Their wide availability together with a huge potential of extending their functionality by additional modules allows developing advanced measuring and monitoring systems by non-specialists. However, using popular example codes often leads the user to pass over or not to be aware of the limitations of the system and drawing too far-reaching...
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Business Sentiment Analysis. Concept and Method for Perceived Anticipated Effort Identification
PublicationRepresenting a valuable human-computer interaction interface, Sentiment Analysis (SA) is applied to a wide range of problems. In the present paper, the researchers introduce a novel concept of Business Sentiment (BS) as a measurement of a Perceived Anticipated Effort (PAE) in the context of business processes (BPs). BS is considered as an emotional component of BP task contextual complexity perceived by a process worker after reading...
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Artificial-Hand Technology—Current State of Knowledge in Designing and Forecasting Changes
PublicationThe subject of human-hand versatility has been intensively investigated for many years. Emerging robotic constructions change continuously in order to mimic natural mechanisms as accurately as possible. Such an attitude is motivated by the demand for humanoid robots with sophisticated end effectors and highly biomimic prostheses. This paper provides wide analysis of more than 80 devices that have been created over the last 40 years....
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Urchin-like TiO2 structures decorated with lanthanide-doped Bi2S3 quantum dots to boost hydrogen photogeneration performance
PublicationThe formation of heterojunctions between wide- and narrow-bandgap photocatalysts is commonly employed to boost the efficiency of photocatalytic hydrogen generation. Herein, the photoactivity of urchin-like rutile particles is increased by decorating with pristine as well as Er- or Yb-doped Bi2S3 quantum dots (QDs) at varied QD loadings (1–20 wt%) and doping degrees (1–15 mol%), and the best hydrogen evolution performance is achieved at...
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Review on Current Status of Echinocandins Use
PublicationFungal infections are rising all over the world every year. There are only five medical compound classes for treatment: triazoles, echinocandins, polyenes, flucytosine and allylamine. Currently, echinocandins are the most important compounds, because of their wide activity spectrum and much lower sides effects that may occur during therapy with other drugs. Echinocandins are secondary metabolites of fungi, which can inhibit the...
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Cognitive Systems, Concepts, Processes, and Techniques for the Age of Industry 4.0
PublicationThe aim of this Guest Edition of Cybernetics and Systems is to present a wide-ranging scale of concepts and processes being currently researched, developed, and evaluated in real life settings in anticipation of incoming Industry 4.0 era. With the fourth industrial revolution expectation, the broad spectrum of cognitive approaches have emerged as an attempt to mimic and augment, in some way, human intelligence. Intelligence, in...
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I, Robot: between angel and evil
PublicationThe boosting of most digital innovations within recent technology progress by artificial intelligence (AI) constitutes a growing topic of interest. Besides its technical aspects, increasing research activity may be observed in the domain of security challenges, and therefore of responsibility related to the controlled or hypothetically uncontrolled or autonomous emergence of AI solutions. Consequently, responsibility and ethics...
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Measurements of the Hydraulic Fluids Compressibility
PublicationPerformance of the hydrostatic high-pressure drive systems is affected by the changes of working fluid’s volume. Presence of air bubbles in the fluid cause this problem to be even more serious. To study this phenomenon precise measurements of fluid’s bulk modulus are necessary. Differ-ent measurement methods are applied, but they are either limited to low pressure range or give inaccurate results. To solve the problem the new...
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Novel 1,2,4-Oxadiazole Derivatives in Drug Discovery
PublicationAbstract: Five-membered 1,2,4-oxadiazole heterocyclic ring has received considerable attention because of its unique bioisosteric properties and an unusually wide spectrum of biological activities. Thus, it is a perfect framework for the novel drug development. After a century since the 1,2,4-oxadiazole have been discovered, the uncommon potential attracted medicinal chemists’ attention, leading to the discovery of a few presently...
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Polish tax reform "Polski Ład" – consequences of introducing changes on the example of selected flat-rate tax forms for micro and small companies
PublicationThis article describes aspects related to the introduction of the latest tax reform in Poland. The changes initiated in January 2022, under the name Polski Ład, concern a wide range of tax changes in Poland. Reform, in a broad sense, is a multidimensional government development program, which is primarily aimed at getting out of the crisis caused by the COVID-19 pandemic and a smooth transition to financing strategic goals in investment...
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Rare earth ions doped K 2 Ta 2 O 6 photocatalysts with enhanced UV–vis light activity
PublicationNew rare earth-doped K2Ta2O6 photocatalysts were successfully synthesized by hydrothermal method. The effect of dopant type (Y,Yb,Ho,Pr,Er) and amount of rare earth precursor (2,4,8 and 10 mol%) on the physicochemical and photocatalytic properties of RE-K2Ta2O6 have been investigated. All as-prepared materials were characterized by UV–vis diffuse reflectance spectroscopy, Brunauer-Emmett-Teller specific surface area measurement,...
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AFM investigation of electrode fabricated by 3D printing
Open Research Data3D printing, also known as additive manufacturing, has enjoyed great interest in recent years due to the versatility of this method of producing various shapes and details. Due to the possibility of precise control of the shape and composition of the printed elements, the discussed technique can be widely used in electrochemistry, including electrochemical...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen MIC1-MAG1-MIC3
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen MIC1-MAG1-ROP1
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen MIC1-MAG1-AMA1
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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A concept of Signal Equalization Method Based on Music Genre and the Listener's Room Characteristics
PublicationA research study that investigates the influence of the room acoustics environment on the frequency characteristic of the audio signal playback is presented. First, a novel spectral equalization method of the room acoustic conditions is introduced. On the basis of the frequency response of the room, a system for room acoustics compensation based on eight-band equalizer is proposed. The system settings depend on music genre. In...
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Phage-Directed Synthesis of Photoluminescent Zinc Oxide Nanoparticles under Benign Conditions
PublicationBiological systems, especially bacteriophages and peptides, are an attractive green alternative to other known methods of nanoparticle synthesis. In this work, for the first time, bacteriophages were employed to synthesize a specific peptide, capable of producing nanoparticles (NPs). Derivatives of M13 bacteriophage exposing a ZnO-binding peptide (TMGA-LGLKWPV) on either pIII or pVIII phage coat protein were constructed and used...
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Superconductivity in the Cu(Ir1-xPtx)2Se4 spinel
PublicationWe report the observation of superconductivity in the CuIr2Se4 spinel induced by partial substitution of Pt for Ir. The optimal doping level for superconductivity in Cu(Ir1-xPtx )2Se4 is x = 0.2, where Tc is 1.76 K. A superconducting Tc vs composition dome is established between the metallic, normal conductor CuIr2Se4 and semiconducting CuIrPtSe4. Electronic structure calculations show that the optimal Tc occurs near the electron count...
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Comparison of direct and inverse methods of satellite observations downscaling for the coastal zone area
PublicationThe Earth observation satellite imaging systems have known limitations, especially regarding their spatial and temporal resolution. Therefore, approaches which aim to combine data retrieved from sensors of higher temporal and lower spatial resolution with the data characterized by lower temporal but higher spatial resolution are of high interest. This allows for joint utilization of the advantages of both these types of sensors....
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Cost-Efficient Design Methodology for Compact Rat-Race Couplers
PublicationIn this article, a reliable and low-cost design methodology for simulation-driven optimization of miniaturized rat-race couplers (RRCs) is presented. We exploit a two-stage design approach, where a composite structure (a basic building block of the RRC structure) is first optimized using a pattern search algorithm, and, subsequently, the entire coupler is tuned by means of surrogate-based optimization (SBO) procedure. SBO is executed...
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Structure and paramagnetism in weakly correlated Y8Co5
PublicationWe report the basic physical properties of monoclinic Y8Co5 determined by means of magnetic susceptibility, electrical resistivity, and specific heat measurements. The crystal structure of Y8Co5 is monoclinic (P21/c) with lattice parameters a = 7.0582(6) Å, b = 7.2894(6) Å, c = 24.2234(19) Å, and β = 102.112(6)° as refined by using synchrotron powder x-ray diffraction data. The compound shows temperature independent paramagnetism...