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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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Design-Oriented Constrained Modeling of Antenna Structures
PublicationFast surrogate models are crucially important to reduce the cost of design process of antenna structures. Due to curse of dimensionality, standard (data-driven) modeling methods exhibit serious limitations concerning the number of independent geometry parameters that can be handled but also (and even more importantly) their parameter ranges. In this work, a design-oriented modeling framework is proposed in which the surrogate is...
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Pretreatment of Lignocellulosic Materials as Substrates for Fermentation Processes
PublicationLignocellulosic biomass is an abundant and renewable resource that potentially contains large amounts of energy. It is an interesting alternative for fossil fuels, allowing the production of biofuels and other organic compounds. In this paper, a review devoted to the processing of lignocellulosic materials as substrates for fermentation processes is presented. The review focuses on physical, chemical, physicochemical, enzymatic,...
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Framework for Structural Health Monitoring of Steel Bridges by Computer Vision
PublicationThe monitoring of a structural condition of steel bridges is an important issue. Good condition of infrastructure facilities ensures the safety and economic well-being of society. At the same time, due to the continuous development, rising wealth of the society and socio-economic integration of countries, the number of infrastructural objects is growing. Therefore, there is a need to introduce an easy-to-use and relatively low-cost...
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Parametric optimization of sandwich composite footbridge with U-shaped cross-section
PublicationParametric optimization of sandwich composite footbridge was presented in the paper. Composite footbridge has 14,5 m long and has U-shaped cross-section with inner dimensions 2,6 × 1,3 m. The sandwich structure in made from GFRP laminate as a faces and PET foam as a core. The aim of analysis was to minimize the mass of the new footbridge that can lead to minimize the cost of structure. After optimization was conducted, the new...
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Constrained aerodynamic shape optimization using neural networks and sequential sampling
PublicationAerodynamic shape optimization (ASO) involves computational fluid dynamics (CFD)-based search for an optimal aerodynamic shape such as airfoils and wings. Gradient-based optimization (GBO) with adjoints can be used efficiently to solve ASO problems with many design variables, but problems with many constraints can still be challenging. The recently created efficient global optimization algorithm with neural network (NN)-based prediction...
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A review on homogeneous and heterogeneous catalytic microalgal lipid extraction and transesterification for biofuel production
PublicationExtracting lipids from microalgal biomass presents significant potential as a cost-effective approach for clean energy generation. This can be achieved through the chemical conversion of lipids to produce fatty acid methyl esters via transesterification. The extraction mainly involves free fatty acids, phospholipids, and triglycerides, and requires less energy, making it an attractive option for satisfying the growing demand for...
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Ensuring sustainable development of urban public transport: A case study of the trolleybus system in Gdynia and Sopot (Poland)
PublicationElectromobility is a vital tool in reducing the environmental impact of transportation. A technologically mature means of public transport is the trolleybus. Based on a case study of the Polish cities of Gdynia and Sopot, this paper explores the factors that influence the development of the trolleybus system. Recent developments of in-motion charging (IMC) technology are analysed what provides a new analytical framework for the...
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Gelatin and gelatin/starch-based films modified with sorbitol for wound healing
PublicationGelatin-based films modified with sorbitol were produced from gelatin solution or gelatin/starch blends using a simple and low-cost solvent casting method, and subsequently, their physicochemical, mechanical, and biocompatibility properties were characterized. This work focused on developing and optimizing a biopolymeric blend to improve the pure biopolymers’ properties for potential biomedical applications such as wound dressing....
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Magnetic superhydrophobic melamine sponges for crude oil removal from water
PublicationThis paper proposes the preparation of a new sorbent material based on melamine sponges (MS) with superhydrophobic, superoleophilic, and magnetic properties. This study involved impregnating the surface of commercially available MS with eco-friendly deep eutectic solvents (DES) and Fe3O4 nanoparticles. The DES selection was based on the screening of 105 eutectic mixtures using COSMO-RS modeling. Other parameters affecting the efficiency...
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Cascaded Buck Hybrid Interlink Converter for Multiple-Input / Multiple-Output Operation
PublicationThe provision of isolated- and non-isolated DC output voltages by Power electronics power-conditioning devices in the recent ‘green-energy-revolution’ era is on course. In this paper, a structure for multi-input multi-output(MIMO) DC–DC buck converter is proposed to generate output voltages of varying levels with fewer component-count. The DC output voltage of each of the constituting buck converters can be used independently or...
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Beeswax And Palmitic Acid Utilization With Heat Pipes For Electronics Cooling
PublicationThis paper presents an experimental study of heat pipes supported by phase change materials (PCMs) coated at their adiabatic sections in application for electronics cooling. The PCMs investigated in this research were palmitic acid and beeswax, the latter being considered as a more cost-effective alternative. The study focused on three powers: 20W, 25W, and 30W. The experimental results revealed that the incorporation of palmitic...
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Active Kriging-based conjugate first-order reliability method for highly efficient structural reliability analysis using resample strategy
PublicationEfficient structural reliability analysis method is crucial to solving reliability analysis of complex structural problems. High-computational cost and low-failure probability problems greatly limit the efficiency in structural reliability analysis problems, causing the safety and reliability of the structure to be questioned. In this work, a highly efficient structural reliability analysis method coupling active Kriging algorithm...
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Machine-Learning Methods for Estimating Performance of Structural Concrete Members Reinforced with Fiber-Reinforced Polymers
PublicationIn recent years, fiber-reinforced polymers (FRP) in reinforced concrete (RC) members have gained significant attention due to their exceptional properties, including lightweight construction, high specific strength, and stiffness. These attributes have found application in structures, infrastructures, wind power equipment, and various advanced civil products. However, the production process and the extensive testing required for...
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DIGITAL HYDRAULICS CIRCUIT BASED ON PWM FUNCTION FOR CONTROLLING HYDRAULIC ACTUATOR POSITION
PublicationHydraulic systems are used in many different industries, such as multi-source hydrostatic drive systems. In traditional hydraulic systems, a proportional servo valve is used to control the position of hydraulic actuators. The low energy efficiency and high cost of these control valves are two major problems with these systems. Digital hydraulics is one of the most unique ideas on how to solve these problems. Researchers like digital...
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Advances in analysis, quantification and modelling of N2O emission in SBRs under various DO set points
PublicationNitrous oxide (N2O), considered a major greenhouse gas (GHG) in wastewater treatment plants (WWTPs), is produced during both nitrification and denitrification processes; hence, it needs to be controlled by internal and external strategies. Various factors, such as DO, temperature, and pH, could be incorporated into the mitigation of emissions in WWTPs. In this research, potential operational strategies were investigated in order...
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The Sonocatalytic Activation of Persulfates on Iron Nanoparticle Decorated Zeolite for the Degradation of 1,4-Dioxane in Aquatic Environments
PublicationIn the chemical industry, 1,4-diethylene dioxide, commonly called dioxane, is widely used as a solvent as well as a stabilizing agent for chlorinated solvents. Due to its high miscibility, dioxane is a ubiquitous water contaminant. This study investigates the effectiveness of catalyst- and ultrasound (US)-assisted persulfate (PS) activation with regard to degrading dioxane. As a first step, a composite catalyst was prepared using...
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The effect of hybridization of fire retarded epoxy/flax-cotton fiber laminates by expanded vermiculite: Structure-property relationship study
PublicationThe study describes the hybridization of epoxy/flax-cotton (EP/FF) composites containing ammonium polyphosphate (APP) with micrometric expanded vermiculite (VMT) (1–10 wt%). The efficiency of hybridization of flame retarded epoxy/flax-cotton composites was assessed by performing static tensile and flexural strength evaluation, supplemented by impact strength measurements of the composites. Moreover, thermal and thermomechanical...
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Hybrid Finite Element Method Development for Offshore Structures’ Calculation with the Implementation of Industry Standards
PublicationIn the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulationand evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modelingand solution rely on finite element methods and cover the simulation of the structure’s properties along with the influenceof the marine environment – sea currents, wave...
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Kriging metamodels and design re‐utilization for fast parameter tuning of antenna structures
PublicationThe paper addresses the problem of computationally efficient electromagnetic (EM)‐driven design closure of antenna structures. The foundations of the presented approach are fast kriging interpolation metamodels, utilized for two purposes: (a) producing a good starting point for further parameter tuning, and (b) yielding a reasonable Jacobian matrix estimate to jump‐start the optimization procedure. The models are rendered using...
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Chemical surface etching methods for ground tire rubber as sustainable approach for environmentally-friendly composites development– a review
PublicationGround tire rubber (GTR) has been used as a sustainable low-cost modifier in various composites. However, due to the hydrophobic nature of GTR, it is in compatible with most matrices and results in deterioration in both mechanical and physical properties of composites. This necessitates pre-modification of the powdered rubber to improve the interfacial bonding at the rubber-matric interface. The most common GTR modification research...
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Microgrid Energy Management System
PublicationIn the era of rapid development of "green energy” and storage devices, microgrids implemented in line with the concept of distributed generation can be an effective form of power management. There is a need for an efficient, optimal and reliable control of the combined infrastructure. The article presents a flexible, configurable microgrid's resources control system, which executes the task of meeting the electricity demand of...
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A Novel Coupling Matrix Synthesis Technique for Generalized Chebyshev Filters With Resonant Source–Load Connection
PublicationThis paper reports a novel synthesis method for microwave bandpass filters with resonant source–load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal coupling matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement...
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Quality Modeling in Grid and Volunteer-Computing Systems
PublicationA model of computational quality in large-scale computing systems was presented in the previous chapter of this book. This model describes three quality attributes: performance, reliability and energy efficiency. We assumed that all processes in the system are incessantly ready to perform calculations and that communication between the processes occurs immediately. These assumptions are not true for grid and volunteer computing...
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Engineering Au nanoparticle arrays on SiO2 glass by pulsed UV laser irradiation
PublicationWe study semi-regular arrays of Au nanoparticles (NP) obtained via UV laser irradiation of thin Au films on glass substrate. The NP structures are prepared from films of a thickness up to 60 nm produced by discharge sputtering or pulsed laser deposition, and annealed by nanosecond laser pulses at 266 or 308 nm, respectively, at fluencies in the range of 60-410 mJ/cm2. For the rare- and close-packed NP structures, consistent description...
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Methods for physical impairment constrained routing with selected protection in all-optical networks
PublicationIn this paper, we investigate the problem of survivable all-optical routing in WDM networks with physical impairments. One of the recent key issues in survivable optical network design refers to maximization of the ratio of routeable demands while keeping the overall network cost low. In WDM networks, this goal can be achieved by routing as many demands in all-optical way as possible. Based on the latest technical trends driven...
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Local-Global Space Mapping for Rapid EM-Driven Design of Compact RF Structures
PublicationIn this work, we introduce a robust and efficient technique for rapid design of compact RF circuits. Our approach exploits two-level space mapping (SM) correction of an equivalent circuit model of the structure under design. The first SM layer (local correction) is utilized to ensure good matching between the equivalent circuit and the electromagnetic model at the component level. On the other hand, the global correction allows...
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The contactless method of chip-to-chip high-speed data transmission monitoring
PublicationThis paper presents a technique of decoupling differential signals transmitted in a pair of microstrip lines on a printed circuit board (PCB), using dedicated coupler for high speed data transmission monitoring in chip-to-chip interconnections. The coupler used for signal probing is overlayed on the pair of microstrip lines under test, and provides a signal to the next blocks of the measurement system without disturbing transmission...
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Design Space Reduction for Expedited Multi-Objective Design Optimization of Antennas in Highly-Dimensional Spaces
PublicationA surrogate-based technique for efficient multi-objective antenna optimization is discussed. Our approach exploits response surface approximation (RSA) model constructed from low-fidelity antenna model data (here, obtained through coarse-discretization electromagnetic simulations). The RSA model enables fast determination of the best available trade-offs between conflicting design goals. The cost of RSA model construction for multi-parameter...
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An Application Supporting Gastroesophageal Multichannel Intraluminal Impedance-pH Analysis
PublicationDue to a significant rise in the number of patients diagnosed with diseases of the upper gastrointestinal tract and the high cost of treatment, there is a need to further research on one of the most popular diagnostic tests used in this case – esophageal Multichannel Intraluminal Impedance and pH measurement. This may lead to finding new diagnostically relevant information, used to quicken and improve the diagnostic procedure....
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Reliable routing and resource allocation scheme for hybrid RF/FSO networks
PublicationSignificant success of wireless networks in the last decade has changed the paradigms of communication networks design. In particular, the growing interest in wireless mesh networks (WMNs) is observed. WMNs offer an attractive alternative to conventional cable infrastructures, especially in urban areas, where the cost of new installations is almost prohibitive. Unfortunately, the performance of WMNs is often limited by the cluttered...
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Real-time simulator of agricultural biogas plant
PublicationThis article presents a real-time simulator of an agricultural biogas plant. The project contains biogas and biomass circuits simulation, as well as heating circuit simulation with a complete control system and visualization interface of the whole process. The software tool used to simulate the plant work is CFD (Computational Fluid Dynamics), which enables a user to create and test simulation objects based on fundamental physical...
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Reduction of noise and rolling resistance by horizontal grinding of asphalt pavements
PublicationGrinding of cement concrete pavements to reduce unevenness and noise is common since a long time. Grinding is then made with wheels equipped with diamond blades rotating in the vertical plane. This creates narrow vertical/longitudinal grooves in the pavement. It is not applied to asphalt pavements. In this paper an alternative type of grinding is studied. In this case plates with diamond heads rotate in the same plane as the pavement,...
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N-doped mesoporous carbon nanosheets obtained by pyrolysis of a chitosan–melamine mixture for the oxygen reduction reaction in alkaline media.
PublicationBy simple thermal decomposition of low-cost precursors (chitosan, melamine) in an inert atmosphere, nitrogen-doped porous carbonaceous materials were prepared. The samples pyrolyzed at 700 C are composed of mainly mesoporous nitrogen-doped carbon nanosheets and partially graphitized carbon. The nanosheets contain a disordered area due to the strain imposed by the presence of nitrogen and/or oxygen groups in their structure. Some...
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Expedited Gradient-Based Design Closure of Antennas Using Variable-Resolution Simulations and Sparse Sensitivity Updates
PublicationNumerical optimization has been playing an increasingly important role in the design of contemporary antenna systems. Due to the shortage of design-ready theoretical models, optimization is mainly based on electromagnetic (EM) analysis, which tends to be costly. Numerous techniques have evolved to abate this cost, including surrogate-assisted frameworks for global optimization, or sparse sensitivity updates for speeding up local...
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Preparation and Properties of Thermoplastic Polyurethane Composites Filled with Powdered Buckwheat Husks
PublicationBio-based fillers for the polymer composites are still interesting from the scientific and industrial point of view, due to their low cost and renewable nature. In this work partially green composites were obtained by the mixing of thermoplastic poly(ester-urethane) with the unmodified and modified (by acetylation) grinded buckwheat husks. Obtained biocomposites were characterized in the terms of their chemical structure (FTIR),...
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Pressure-induced flow processing behind the superior mechanical properties and heat-resistance performance of poly(butylene succinate)
PublicationWe propose a pressure-induced flow (PIF) processing method for the simultaneous enhancement of strength, toughness, and heat resistance of biodegradable poly(butylene succinate) (PBS). The pressure and temperature were systematically adjusted to optimize the tensile strength of PBS. Under the optimized processing conditions, the structured PBS was characterized by relatively high strength of 89.5 MPa, toughness of 21.4 kJ·m−2 ,...
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Super tough interpenetrating polymeric network of styrene butadiene rubber‐poly (methyl methacrylate) incorporated with general purpose carbon black ( N660 )
PublicationA classic set of polymeric interpenetrating polymeric network (IPN) microcomposites has been fabricated using an elastomer—styrene butadiene rubber [SBR], a thermoplastic poly(methyl methacrylate)-PMMA and with carbon black (CB)-N660 as a filler and reinforcing agent. This synthesized IPN composite can be promisingly employed as a toughened plastic and vibrational damper in a wide service range with excellent thermal stability,...
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Development of Safirinium dyes for new applications: fluorescent staining of bacteria, human kidney cells, and the horny layer of the epidermis
PublicationLow-molecular synthetic fluorophores are convenient tools in bioimaging applications. Several derivatives of Safirinium dyes as well as their reactive N-hydroxysuccinimide (NHS) esters bearing diverse substituents were synthesized and evaluated experimentally in terms of their lipophilicity by means of reverse-phase and immobilized artificial membrane high-performance liquid chromatography. Subsequently, the selected compounds...
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Numerical analysis of CO2-water separation in a horizontal double T-junction
PublicationCarbon dioxide is considered one of the main factors leading to global warming. Considering the significant impacts of CO2 on climate change, various technologies have been developed in recent decades to control carbon emission, such as for example CO2 capture and storage. The developed cycle of a negative CO2 emission power plant includes some devices, out of which, separator plays an indispensable role. To this end, T-junction...
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Constructing a map of an anonymous graph: applications of universal sequences
PublicationWe study the problem of mapping an unknown environmentrepresented as an unlabelled undirected graph. A robot (or automaton)starting at a single vertex of the graph G has to traverse the graph and return to its starting point building a map of the graph in the process. We are interested in the cost of achieving this task (whenever possible) in terms of the number of edge traversal made by the robot. Another optimization criteria...
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Maximum Power Point Technique (MPPT) for PV System Based on Improved Pert and Observe (P&O) Method with PI Controller
PublicationPhotovoltaic power generation system has key rule in electricity production. Although, it is clean renewable energy with unlimited resources but it has some drawbacks in efficiency. In order to maximize the efficiency, PV array must drive at maximum power point. For the reason so, several algorithms are used in PV system to track MPP and reduce the...
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Use of MAG1 recombinant antigen for diagnosis of Toxoplasma gondii infection in humans
PublicationPraca opisuje klonowanie, oczyszczanie oraz zastosowanie w immunodiagnostyce toksoplazmozy antygenu rekombinantowego macierzy cyst tkankowych (MAG1) Toxoplasma gondii. Zastosowany system ekspresyjny pozwolił uzyskać dużą ilość rekombinantowego antygenu, który następnie wykorzystano w teście ELISA do wykrywania specyficzych przeciwciał anty-T. gondii klasy IgG w surowicach pacjentów chorych na toksoplazmozę. W przeprowadzonych badaniach...
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an intelligent image processing sensor - the algorithm and the hardware implementation
PublicationW artykule przedstawiono algorytm przeznaczony do rozpoznawania obiektów ruchomych w obrazie do celu analizy ruchu pojazdów. Algorytm został zrealizowany w układzie FPGA.Ang.: This paper describes the idea and theimplementation of the robust algorithm dedicated toextraction of moving vehicles from real-time cameraimages for the evaluation of traffic parameters, suchas the number of vehicles, their direction of movementand their...
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A hybrid-mesh solution for coverage issues in WiMAX metropolitan area networks.
PublicationThe new WiMAX technology offers several advantages over the currently available (GSM or UMTS-based) solutions. It is a cost effective, evolving, and robust technology providing quality of service guarantees, high reliability, wide coverage and non-line-of-sight (NLOS) transmission capabilities. All these features make it particularly suitable for densely populated urban environments. In this paper we discuss the design and implementation...
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Aspekt ekonomiczny ogrzewania wolnostojącego budynku powietrzną pompą ciepła
PublicationArtykuł poświęcony ocenie ekonomicznej ogrzewania wolnostojącego budynku mieszkalnego z wykorzystaniem powietrznej pompy ciepła pracującej w systemie biwalentnym monoenergetycznym. Podstawę analizy stanowi projekt systemu ogrzewania oparty na sprężarkowej pompie ciepła typu powietrze - woda ( P-W ) dla wolnostojącego budynku mieszkalnego o powierzchni użytkowej 140 m2. Ocenę ekonomiczną tego rozwiązania przeprowadzono w oparciu...
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Zero-pole approach to computer aided design of in-line siw filters with transmission zeros
PublicationThis paper presents a design of a new type of in-line pseudo-elliptic filters implemented in substrate integrated waveguide(SIW) technology. To realize transmission zeros in in-line topology,frequency-dependent couplings were used. Such dispersive couplingswere implemented as shorted stubs. The design process startswith the generation of a suitable starting point. To this end, anapproximation of SIW as a rectangular waveguide is...
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Determinants of SME location in a suburban area: Evidence from the Gdańsk–Gdynia–Sopot metropolitan area.
PublicationGiven the importance of small and medium enterprises (SMEs) in the European economy, it is essential to have adequate information about the various factors that determine their choice of location. However, the size of a company is often an aspect not covered in theoretical studies and empirical research on industrial locations and urban planning. This article examines the place of residence...
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A memory efficient and fast sparse matrix vector product on a Gpu
PublicationThis paper proposes a new sparse matrix storage format which allows an efficient implementation of a sparse matrix vector product on a Fermi Graphics Processing Unit (GPU). Unlike previous formats it has both low memory footprint and good throughput. The new format, which we call Sliced ELLR-T has been designed specifically for accelerating the iterative solution of a large sparse and complex-valued system of linear equations arising...
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Estimation of DC motor parameters using a simple CMOS camera
PublicationDifferent components of control systems for mobile robots are based on dynamic models. In low-cost solutions such a robot is wheeled and equipped with DC motors, which have to be included in the model of the robot. The model is fairly simple but determination of its parameters needs not to be easy. For instance, DC motor parameters are typically identified indirectly using suitable measurements, concerning engine voltage, current,...