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Search results for: MULTI-RESOLUTION ANALYSIS
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Rapid multi-objective simulation-driven design of compact microwave circuits
PublicationA methodology for rapid multi-objective design of compact microwave circuits is proposed. Our approach exploits point-by-point Pareto set identification using surrogate-based optimization techniques, auxiliary equivalent circuit models, and space mapping as the major model correction method. The proposed technique is illustrated and validated through the design of a compact rat-race coupler. A set of ten designs being trade-offs...
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Comparison of Algorithms for Profile-Based Alignment of Low Resolution MALDI-ToF Spectra
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Adjusted subpixel method enables optimisation of bronchial measurements in high-resolution CT
PublicationArtykuł przedstawia metodę korekcji pomiaru rozmiaru oskrzeli w techice HRCT. W celu walidacji metody zastosowano fantom. W efekcie opracowano metodę nieliniowej predykcji rzeczywistych rozmiarów ścianek małych oskrzeli w obrazach HRCT.
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Multi-layered mineral glass units used as viewport elements of underwater ship structures
PublicationIn the paper, Authors deals with viewport elements of underwater marine constructions. If a single-plate viewport constructions are considered, big thicknesses of the glass plate are required to resist the pressure. To build the viewports from the commercially accessible glass panes, multi-layered glass units are proposed in the paper. Numerical calculations are presented, summarized and compared with experimental tests. Focusing...
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Multi-Objective Design Optimization of Compact Quasi-Isotropic Dielectric Resonator Antenna
PublicationMulti-objective optimization of a quasi-isotropic dielectric resonator antenna (DRA) is presented. Utilization of variable-fidelity electromagnetic (EM) DRA models, response surface approximations, and response correction techniques, allows us to obtain—at a low computational cost—a set of alternative antenna designs representing the best possible trade-offs between three conflicting objectives: antenna size, its reflection response,...
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High gain/bandwidth off‑chip antenna loaded with metamaterial unit‑cell impedance matching circuit for sub‑terahertz near‑field electronic systems
PublicationAn innovative off-chip antenna (OCA) is presented that exhibits high gain and efficiency performance at the terahertz (THz) band and has a wide operational bandwidth. The proposed OCA is implemented on stacked silicon layers and consists of an open circuit meandering line. It is shown that by loading the antenna with an array of subwavelength circular dielectric slots and terminating it with a metamaterial unit cell, its impedance...
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A new type of (TiZrNbTaHf)N/MoN nanocomposite coating: Microstructure and properties depending on energy of incident ions
PublicationA novel (TiZrNbTaHf)N/MoN nanocomposite coatings, which consist of the nitride of the high-entropy alloy and the binary nitride, were synthesized by vacuum-arc deposition at various substrate biases. The elemental composition, chemical bonding state, phase structure, microstructure and mechanical properties of the coatings were studied by high-resolution experimental methods: SIMS, GDMS, XPS, XRD, HR-TEM and nano-indentation. It...
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Comparative Lipidomic Study of Human Milk from Different Lactation Stages and Milk Formulas
PublicationIn this report, we present a detailed comparison of the lipid composition of human milk (HM) and formula milk (FM) targeting different lactation stages and infant age range. We studied HM samples collected from 26 Polish mothers from colostrum to 19 months of lactation, along with FM from seven brands available on the Polish market (infant formula, follow-on formula and growing-up formula). Lipid extracts were analysed using liquid...
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An Instantaneous Engine Speed Estimation Method Using Multiple Matching Synchrosqueezing Transform
PublicationInstantaneous rotational speed measurement of the engine is crucial in routine inspection and maintenance of an automobile engine. Since the contact measurement of rotational speed is not always available, the vibration measurement has been used for noncontact rotational speed estimation methods. Unfortunately, the accuracy of the noncontact estimation methods by analyzing engine vibration frequency is not satisfactory due to the...
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New nanoadsorbent based on magnetic iron oxide containing 1,4,7,10-tetraazacyclododecane in outer chain (Fe3O4@SiO2-cyclen) for adsorption and removal of selected heavy metal ions Cd2+, Pb2+, Cu2+
PublicationMagnetic Fe3O4@SiO2-cyclen nanoparticles were prepared and used as adsorbent for Cd2+, Pb2+ and Cu2+ from aqueous solution removal process controlled with differential pulse anodic stripping voltammetry (DPASV) and hanging mercury drop electrode (HDME). Nanomaterial was synthesised in three-step process co-precipitation of Fe3O4 core, coating with silane and N-(3-(triethoxysilyl)propyl)-1,4,7,10-tetraazacyclododecane-1-carboxamide...
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Highly Occupied Surface States at Deuterium-Grown Boron-Doped Diamond Interfaces for Efficient Photoelectrochemistry
PublicationPolycrystalline boron-doped diamond is a promising material for high-power aqueous electrochemical applications in bioanalytics, catalysis, and energy storage. The chemical vapor deposition (CVD) process of diamond forma-tion and doping is totally diversified by using high kinetic energies of deu-terium substituting habitually applied hydrogen. The high concentration of deuterium in plasma induces atomic arrangements and steric...
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One More Step Towards a Circular Economy for Thermal Insulation Materials—Development of Composites Highly Filled with Waste Polyurethane (PU) Foam for Potential Use in the Building Industry
PublicationThe rapid development of the building sector has created increased demand for novel materials and technologies, while on the other hand resulting in the generation of a severe amount of waste materials. Among these are polyurethane (PU) foams, which are commonly applied as thermal insulation materials. Their management is a serious industrial problem, due to, for example, their complex chemical composition. Although some chemical...
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Neural Architecture Search for Skin Lesion Classification
PublicationDeep neural networks have achieved great success in many domains. However, successful deployment of such systems is determined by proper manual selection of the neural architecture. This is a tedious and time-consuming process that requires expert knowledge. Different tasks need very different architectures to obtain satisfactory results. The group of methods called the neural architecture search (NAS) helps to find effective architecture...
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Unveiling the Pool of Metallophores in Native Environments and Correlation with Their Potential Producers
PublicationFor many organisms, metallophores are essential biogenic ligands that ensure metal scavenging and acquisition from their environment. Their identification is challenging in highly organic matter rich environments like peatlands due to low solubilization and metal scarcity and high matrix complexity. In contrast to common approaches based on sample modification by spiking of metal isotope tags, we have developed a two-dimensional...
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In Situ Random Microseeding and Streak Seeding Used for Growth of Crystals of Cold-Adapted beta-D-Galactosidases: Crystal Structure of betaDG from Arthrobacter sp. 32cB
PublicationThere is an increasing demand for cold-adapted enzymes in a wide range of industrial branches. Nevertheless, structural information about them is still scarce. The knowledge of crystal structures is important to understand their mode of action and to design genetically engineered enzymes with enhanced activity. The most difficult task and the limiting step in structural studies of cold-adapted enzymes is their crystallization,...
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Application of multisensoral remote sensing data in the mapping of alkaline fens Natura 2000 habitat
PublicationThe Biebrza River valley (NE Poland) is distinguished by largely intact, highly natural vegetation patterns and very good conservation status of wetland ecosystems. In 2013⿿2014, studies were conducted in the upper Biebrza River basin to develop a remote sensing method for alkaline fen classification ⿿ a protected Natura 2000 habitat (code 7230) ⿿ using remote sensing technologies. High resolution airborne true colour (RGB) and...
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User experience evaluation study on the quality of 1K, 2K, and 4K H.265/HEVC video content
PublicationNowadays, most content creators focus on distributing rich media at the highest possible resolution. Currently, the majority of sold consoles, media players, computer hardware, as well as displays and TVs are advertised as 4K-compatible. The same trend is observed in the case of popular online streaming services and terrestrial TV broadcasts. Generally speaking, it is assumed that higher bitrates provide higher subjective judgements....
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Data fusion of sparse, heterogeneous, and mobile sensor devices using adaptive distance attention
PublicationIn environmental science, where information from sensor devices are sparse, data fusion for mapping purposes is often based on geostatistical approaches. We propose a methodology called adaptive distance attention that enables us to fuse sparse, heterogeneous, and mobile sensor devices and predict values at locations with no previous measurement. The approach allows for automatically weighting the measurements according to a priori...
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Rapid multi-objective optimization of antennas using nested kriging surrogates and single-fidelity EM simulation models
PublicationEver increasing performance requirements make the design of contemporary antenna systems a complex and multi-stage process. One of the challenges, pertinent to the emerging application areas but also some of the recent trends (miniaturization, demands for multi-functionality, etc.), is the necessity of handling several performance figures such as impedance matching, gain, or axial ratio, often over multiple frequency bands. 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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University Students’ Research on Artificial Intelligence and Knowledge Management. A Review and Report of Multi-case Studies
PublicationLeading technologies are very attractive for students preparing their theses as the completion of their studies. Such an orientation of students connected with professional experiences seems to be a crucial motivator in the research in the management and business areas where these technologies condition the development of professional activities. The goal of the paper is the analysis of students’ thesis topics defended in the last...
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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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Rapid multi-objective design optimization of miniaturized impedance transformer by Pareto front exploration
PublicationFast 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
PublicationMulti-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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Recent Advances in Accelerated Multi-Objective Design of High-Frequency Structures using Knowledge-Based Constrained Modeling Approach
PublicationDesign automation, including reliable optimization of engineering systems, is of paramount importance for both academia and industry. This includes the design of high-frequency structures (antennas, microwave circuits, integrated photonic components), where the appropriate adjustment of geometry and material parameters is crucial to meet stringent performance requirements dictated by practical applications. Realistic design has...
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Connectivity in Multi-Interface Networks
PublicationRozważano zagadnienie minimalizacji energii w sieciach bezprzewodowych bez infrastruktury, w których niektóre węzły są wyposażone w więcej, niż jeden interfejs. W przyjętym modelu sieci podano nowe algorytmy przybliżone oraz wyniki dotyczące złożoności obliczeniowej dla problemu najtańszej spójnej podsieci spinającej.
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The Workshop on Multi-Phase Flows
PublicationPrzedstawiono ideę warsztatów ''Modelowanie przepływów wielofazowych w układach termochemicznych'' - organizowanych corocznie - od 2000 roku, przez Podsekcję Przepływów Wielofazowych Komitetu Mechaniki PAN. Omówiono tematykę VI Warsztatów, które były poświęcone głównie metodom eksperymentalnym.
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A Multi-Fidelity Surrogate-Model-Assisted Evolutionary Algorithm for Computationally Expensive Optimization Problems
PublicationIntegrating data-driven surrogate models and simulation models of different accuracies (or fideli-ties) in a single algorithm to address computationally expensive global optimization problems has recently attracted considerable attention. However, handling discrepancies between simulation models with multiple fidelities in global optimization is a major challenge. To address it, the two major contributions of this paper include:...
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Multi-state vibronic interactions in the fluorobenzene radical cation: The importance of quadratic coupling terms
PublicationThe multi-mode multi-state vibronic interactions in the set of X^2B_1 - D^2A_1 electronic states of the monofluoro benzene radical cation are investigated theoretically, based on a quadratic vibronic coupling approach. The underlying ionization potentials and coupling constants are obtained from ab initio coupled-cluster calculations. Previous investigations (relying on the linear coupling approach) are extended by including all...
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Simulation-driven size-reduction-oriented design of multi-band antennas by means of response features
PublicationThis study addresses the problem of explicit size reduction of multi-band antennas by means of simulation-driven optimisation. The principal difficulty of electromagnetic (EM)-based miniaturisation of multi-band antennas is that several resonances have to be controlled independently (both in terms of their frequency allocation and depth) while attempting to reduce physical dimensions of the structure at hand. The design method...
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A high-accuracy complex-phase method of simulating X-ray propagation through a multi-lens system
PublicationThe propagation of X-ray waves through an optical system consisting of many X-ray refractive lenses is considered. For solving the problem for an electromagnetic wave, a finite-difference method is applied. The error of simulation is analytically estimated and investigated. It was found that a very detailed difference grid is required for reliable and accurate calculations of the propagation of X-ray waves through a multi-lens...
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Electricity demand prediction by multi-agent system with history-based weighting
PublicationEnergy and load demand forecasting in short-horizons, over an interval ranging from one hour to one week, is crucial for on-line scheduling and security functions of power system. Many load forecasting methods have been developed in recent years which are usually complex solutions with many adjustable parameters. Best-matching models and their relevant parameters have to be determined in a search procedure. We propose a hybrid...
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Multi-Fidelity Local Surrogate Model for Computationally Efficient Microwave Component Design Optimization
PublicationIn 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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Multi-mode vibronic interactions in the five lowest electronic states of the fluorobenzene radical cation
PublicationThe multi-mode vibronic interactions between the five lowest electronic states of the fluorobenzene radical cation are investigated theoretically, based on ab initio electronic structure data, and employing the linear vibronic coupling model. Low-energy conical intersections, and strong vibronic couplings are found to prevail within the set of X-A and B-C-D cationic states, while the interactions between these two sets of states...
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Charakterystyka odpadów wiertniczych powstających podczas wydobycia gazu z łupków
PublicationPodczas prac wiertniczych powstają różne rodzaje odpadów różniące się pod względem składu i właściwości. Urobek (tzw. zwierciny/zmielona skała z płuczką wiertniczą), powstający podczas wiercenia górotworu, jest często wykorzystywany do rekultywacji nieczynnych składowisk odpadów lub wyrobisk górniczych. Do podstawowych informacji niezbędnych dla szczegółowej charakterystyki geologicznej danego złoża zalicza się ilościowe metody...
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Multi-DBD plasma actuator for flow separation control around NACA 0012 and NACA 0015 airfoil models
PublicationIn this paper application of innovative multi-DBD plasma actuator for flow separation control is presented. The influence of the airflowgenerated by this actuator on the flow around NACA 0012 and NACA 0015 airfoil models was investigated. The results obtained from 2D PIVmeasurements showed that the multi-DBD actuator with floating interelectrode can be attractive for leading and trailing edge separation control.
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Framework of an Evolutionary Multi-Objective Optimisation Method for Planning a Safe Trajectory for a Marine Autonomous Surface Ship
PublicationThis paper represents the first stage of research into a multi-objective method of planning safe trajectories for marine autonomous surface ships (MASSs) involved in encounter situations. Our method applies an evolutionary multi-objective optimisation (EMO) approach to pursue three objectives: minimisation of the risk of collision, minimisation of fuel consumption due to collision avoidance manoeuvres, and minimisation of the extra...
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Investigation of Performance and Energy Consumption of Tokenization Algorithms on Multi-core CPUs Under Power Capping
PublicationIn this paper we investigate performance-energy optimization of tokenizer algorithm training using power capping. We focus on parallel, multi-threaded implementations of Byte Pair Encoding (BPE), Unigram, WordPiece, and WordLevel run on two systems with different multi-core CPUs: Intel Xeon 6130 and desktop Intel i7-13700K. We analyze execution times and energy consumption for various numbers of threads and various power caps and...
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Features of irregularity in examples of Polish multi-family architecture constructed in 2011–2021 and nominated for the Mies van der Rohe award
PublicationThis article is devoted to the analysis of contemporary Polish multi-family architecture in the context of aesthetic irregularity. The research was limited to constructions from 2011–2021 and nominated for the Mies van der Rohe award as the objects with the greatest potential impact on shaping further trends. In their research, the authors focused on searching for the features of irregularities, which, in their opinion, have become...
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Expedited constrained multi-objective aerodynamic shape optimization by means of physics-based surrogates
PublicationIn the paper, computationally efficient constrained multi-objective design optimization of transonic airfoil profiles is considered. Our methodology focuses on fixed-lift design aimed at finding the best possible trade-offs between the two objectives: minimization of the drag coefficient and maximization of the pitching moment. The algorithm presented here exploits the surrogate-based optimization principle, variable-fidelity computational...
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Multi-Objective Water Distribution Systems Control of Pumping Cost, Water Quality, and Storage-Reliability Constraints
PublicationThis work describes a multi-objective model for trading-off pumping cost and water quality for water distribution systems operation. Constraints are imposed on flows and pressures, on periodical tanks operation, and on tanks storage. The methodology links the multi-objective SPEA2 algorithm with EPANET, and is applied on two example applications of increasing complexity, under extended period simulation conditions and variable...
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Repeated Projectile Impact Tests on Multi-Layered FibrousCementitious Composites
PublicationThis research aims to experimentally evaluate the behaviour of multi-layered fibrous cementitious composites withintermediate Glass Fibre Meshes (GFM) under repeated projectile load. The impact load was subjected through a convexedge projectile needle at a low velocity on cylindrical specimens of three-layered fibrous cementitious composites, whichhave two different steel fibre distributions. In series A mixtures, a constant steel...
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Monitoring the gas turbine start-up phase on the platform using a hierarchical model based on Multi-Layer Perceptron networks
PublicationVery often, the operation of diagnostic systems is related to the evaluation of process functionality, where the diagnostics is carried out using reference models prepared on the basis of the process description in the nominal state. The main goal of the work is to develop a hierarchical gas turbine reference model for the estimation of start-up parameters based on multi-layer perceptron neural networks. A functional decomposition...
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On deterministic procedures for low-cost multi-objective design optimization of miniaturized impedance matching transformers
PublicationPurpose This paper aims to investigate deterministic strategies for low-cost multi-objective design optimization of compact microwave structures, specifically, impedance matching transformers. The considered methods involve surrogate modeling techniques and variable-fidelity electromagnetic (EM) simulations. In contrary to majority of conventional approaches, they do not rely on population-based metaheuristics, which permit lowering...
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Parallelization of Selected Algorithms on Multi-core CPUs, a Cluster and in a Hybrid CPU+Xeon Phi Environment
PublicationIn the paper we present parallel implementations as well as execution times and speed-ups of three different algorithms run in various environments such as on a workstation with multi-core CPUs and a cluster. The parallel codes, implementing the master-slave model in C+MPI, differ in computation to communication ratios. The considered problems include: a genetic algorithm with various ratios of master processing time to communication...
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Rapid multi-objective design optimisation of compact microwave couplers by means of physics-based surrogates
PublicationThe authors introduce a methodology for fast multi-objective design optimisation of miniaturised microwave couplers. The approach exploits the surrogate-based optimisation paradigm with an underlying low-fidelity model constructed from an equivalent circuit of the structure under consideration, corrected through implicit and frequency space mapping. A fast prediction tool obtained this way is subsequently optimised by a multi-objective...
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Informal employment in Poland: an empirical spatial analysis
PublicationThe main goal of our article is to bridge the gap in the regional analysis of informal employment in Poland and in particular to indicate the propensity for informal work in the working-age population, to test if informal activities are typical for marginalized people (less educated, unemployed, older) and to identify the regional and spatial heterogeneity in the propensity. We use data from the ‘Human Capital Balance 2010–2014’...
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Nested Kriging Surrogates for Rapid Multi-Objective Optimization of Compact Microwave Components
PublicationA procedure for rapid EM-based multi-objective optimization of compact microwave components is presented. Our methodology employs a recently developed nested kriging modelling to identify the search space region containing the Pareto-optimal designs, and to construct a fast surrogate model. The latter permits determination of the initial Pareto set, further refined using a separate surrogate-assisted process. As an illustration,...
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Dataset Characteristics and Their Impact on Offline Policy Learning of Contextual Multi-Armed Bandits
PublicationThe Contextual Multi-Armed Bandits (CMAB) framework is pivotal for learning to make decisions. However, due to challenges in deploying online algorithms, there is a shift towards offline policy learning, which relies on pre-existing datasets. This study examines the relationship between the quality of these datasets and the performance of offline policy learning algorithms, specifically, Neural Greedy and NeuraLCB. Our results...
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Multi-objective optimization of microwave couplers using corrected domain patching
PublicationPractical design of microwave components and circuits is a compromise between various, often conflicting objectives. In case of compact structures, the trade-offs are typically concerned with the circuit size and its electrical performance. Comprehensive information about the best possible trade-offs can be obtained by means of multi-objective optimization. In this paper, we propose a computationally efficient technique for identifying...