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Search results for: RESPONSE SURFACE METHODOLOGY
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Fast Multi-Objective Optimization of Narrow-Band Antennas Using RSA Models and Design Space Reduction
PublicationComputationally efficient technique for multi-objective design optimization of narrow-band antennas is presented. In our approach, the corrected low-fidelity antenna model (obtained through coarse-discretization EM simulations) is enhanced using frequency scaling and response correction, sampled, and utilized to obtain a fast response surface approximation (RSA) antenna surrogate. The RSA model is constructed in the reduced design space....
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Influence of selected CO2 absorption promoters on the characteristics of calcium carbonate particles produced by carbonation of the post-distillation liquid from the Solvay process
PublicationThe aim of this work is to compare the effect of selected process parameters, gas flow rate, CO2 absorption promoter concentration and its pKa, on the precipitation of CaCO3 by the gas-liquid method using a model post-distillation liquid from the Solvay process. To ensure effective capture of CO2, the absorption promoters used were ammonia, triethanolamine and triethylamine. The Box-Behnken Design was applied to plan the experiments....
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Study of a Multicriterion Decision-Making Approach to the MQL Turning of AISI 304 Steel Using Hybrid Nanocutting Fluid
PublicationThe enormous use of cutting fluid in machining leads to an increase in machining costs, along with different health hazards. Cutting fluid can be used efficiently using the MQL (minimum quantity lubrication) method, which aids in improving the machining performance. This paper contains multiple responses, namely, force, surface roughness, and temperature, so there arises a need for a multicriteria optimization technique. Therefore,...
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Rapid multi-objective antenna design using point-by-point Pareto set identification and local surrogate models
PublicationAntenna design is inherently a multicriterial problem.Determination of the best possible tradeoffs between conflicting objectives (a so-called Pareto front), such as reflection response, gain, and antenna size, is indispensable from the designer’s point of view, yet challenging when high-fidelity electromagnetic (EM) simulations are utilized for performance evaluation. Here, a novel and computationally...
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Mesoscopic impedance analysis of solid materials surface
PublicationSeveral techniques have been developed in order to characterize electrical properties of surfaces in micrometer/nanometer scale. Obtaining of the spatial distribution of sample resistance, capacitance or potential requires separate measurements performed in different scanning modes. On the other hand, analysis of the frequency response of investigated system enables determination of several physical quantities in single measurement...
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Rapid design of miniaturised branch-line couplers through concurrent cell optimisation and surrogate-assisted fine-tuning
PublicationIn this study, the authors introduce a methodology for low-cost simulation-driven design optimisation of highly miniaturised branch-line couplers (BLCs). The first stage of their design approach exploits fast concurrent optimisation of geometrically dependent, but electromagnetically isolated cells that constitute a BLC. The cross-coupling effects between the cells are taken into account in the second stage, where a surrogate-assisted...
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Zastosowanie metod doświadczalnych w charakterystyce właściwości przetwórczych regeneratów gumowych otrzymywanych w współbieżnej wytłaczarce dwuślimakowej
PublicationTermomechaniczną regenerację miału gumowego (GTR) prowadzono przy użyciu współbieżnej wytłaczarki dwuślimakowej. Zastosowanie metody powierzchni odpowiedzi RSM (ang.: Response Surface Methodology) pozwoliło na scharakteryzowanie wpływu warunków termomechanicznej regeneracji odpadów gumowych (temperatury cylindra wytłaczarki, prędkości obrotowej ślimaków oraz wydajności wytłaczania) na przebieg procesu regeneracji (moment obrotowy)...
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Studying the Effect of Working Conditions on WEDM Machining Performance of Super Alloy Inconel 617
PublicationWire electrical discharge machining (WEDM) has been for many years a precise and efficient non-conventional manufacturing solution in various industrial applications, mostly involving the use of hard-to machine materials like, among other, the Inconel super alloys. The focus of the present study is on exploring the effect of selected control parameters, including pulse duration, pulse-off time and the dielectric flow pressure on...
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Blowing Kinetics, Pressure Resistance, Thermal Stability, and Relaxation of the Amorphous Phase of the PET Container in the SBM Process with Hot and Cold Mold. Part I: Research Methodology and Results
PublicationThe technology of filling drinks without preservatives (such as fresh juices, iced tea drinks, vitaminized drinks) is carried out using hot filling. Mainly due to the production costs and lower carbon footprint, polyethylene terephthalate bottles, commonly called PET, are increasingly used in this technology. In this paper, the main aim is to describe the statistical analysis methodology of the influence of the temperature of the...
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Efficient Multi-Objective Simulation-Driven Antenna Design Using Co-Kriging
PublicationA methodology for fast multi-objective antenna optimization is presented. Our approach is based on response surface approximation (RSA) modeling and variable-fidelity electromagnetic (EM) simulations. In the design process, a computationally cheap RSA surrogate model constructed from sampled coarse-discretization EM antenna simulations is optimized using a multi-objective evolutionary algorithm. The initially determined Pareto...
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Fast surrogate-assisted simulation-driven design of compact microwave hybrid couplers
PublicationThis work presents a robust methodology for expedited simulation-driven design optimization of compact microwave hybrid couplers. The technique relies on problem decomposition, and a bot-tom–up design strategy, starting from the level of basic building blocks of the coupler, and finishing with a tuning procedure that exploits a fast surrogate model of the entire structure. The latter is constructed by cascading local response surface...
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An enhanced method in predicting tensile behaviour of corroded thick steel plate specimens by using random field approach
PublicationThe present work investigates the possibility of using random field techniques in modelling the mechanical behaviour of corroded thick steel plate specimens. The nonlinear Finite Element method, employing the explicit dynamic solver, is used to analyse the mechanical properties of typical specimens. A material model considering full nonlinearity is used to evaluate the stress-strain response. The influence of major governing parameters...
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Investigation of the Few‐Layer Black Phosphorus Degradation by the Photonic Measurements
PublicationFew-layer black phosphorus (FLBP) is a 2D material that gains worldwide interest for its possible applications, mainly in electronics and optoelec-tronics. However, as FLBP is prone to a degradation process under envi-ronmental conditions, there is a need for a monitoring method allowing investigation of its surface quality. Among many techniques, optoelectronic ones have unique advantages of fast response, non-contact, and non-invasive...
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Organic Vapor Sensing Mechanisms by Large-Area Graphene Back-Gated Field-Effect Transistors under UV Irradiation
PublicationThe gas sensing properties of graphene back-gated field-effect transistor (GFET) sensors toward acetonitrile, tetrahydrofuran, and chloroform vapors were investigated with the focus on unfolding possible gas detection mechanisms. The FET configuration of the sensor device enabled gate voltage tuning for enhanced measurements of changes in DC electrical characteristics. Electrical measurements were combined with a fluctuation-enhanced...
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Indirect Determination of MCPD Fatty Acid Esters in Lipid Fractions of Commercially Available Infant Formulas for the Assessment of Infants’ Health Risk
PublicationMCPD esters are intensively investigated food lipid contaminants for over a decade. Concern related to their presence in various types of food products is related to the fact that possible free MCPD release from its esterified form during digestion may lead to elevated daily intake of these toxicants.Special attention should be devoted into powdered infant formulas, which contain significant amounts of refined vegetable oils, likely...
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Reliability assessment of an OVH HV power line truss transmission tower subjected to seismic loading
PublicationThe study focuses on the reliability of a transmission tower OS24 ON150 + 10, an element of an OVH HV power line, under seismic loading. In order to describe the seismic force, the real-life recording of the horizontal component of the El Centro earthquake was adopted. The amplitude and the period of this excitation are assumed random, their variation is described by Weibull distribution. The possible space state of the phenomenon...
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Chromium‑based metal organic framework for pipette tip micro‑solid phase extraction: an effective approach for determination of methyl and propyl parabens in wastewater and shampoo samples
PublicationAbstract Background A chromium-based metal organic framework was synthesized and employed as an efficient sorbent for pipette tip micro-solid phase extraction and preconcentration of parabens from wastewater and shampoo samples up to sub-ppb level before their spectrophotometric analysis. Results Factors affecting preconcentration including volume and type of solvent, amount of sorbent, number of extraction, and volume and pH of...
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Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublicationSalting-out assisted liquid-liquid microextraction (SALLME) was integrated with the derivatization procedure to establish a one-step sample pre-treatment approach for rapid analysis of 14 biogenic amines (BAs) in fruit juices. The methodology consists of salting-out of analytes, derivatization with ethyl chloroformate (ECF), extraction with ethyl acetate (EtAc), and the analysis of the derivatized BAs using gas chromatography-mass...
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Investigation of the Effects of Tool Positioning Factors on Peak Temperature in Dissimilar Friction Stir Welding of AA6061-T6 and AA7075-T6 Aluminum Alloys
PublicationAmong the emerging new welding techniques, friction stir welding (FSW) is used frequently for welding high-strength aluminum alloys that are difficult to weld by conventional fusion-welding techniques. This paper investigated the effects of tool-positioning factors on the maximum temperature generated in the dissimilar FSW joint of AA6061-T6 and AA7075-T6 aluminum alloys. Three factors of plunge depth, tool offset, and tilt angle...
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Effect of rPET Content and Preform Heating/Cooling Conditions in the Stretch Blow Molding Process on Microcavitation and Solid-State Post-Condensation of vPET-rPET Blend: Part II—Statistical Analysis and Interpretation of Tests
PublicationThis research explores how varying proportions of virgin polyethylene terephthalate (vPET) and recycled polyethylene terephthalate (rPET) in vPET-rPET blends, combined with preform thermal conditions during the stretch blow molding (SBM) process, influence PET bottles’ microscopic characteristics. Key metrics such as viscosity, density, crystallinity, amorphous phase relaxation, and microcavitation were assessed using response...
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Application of chemometric modeling for ionic liquid-based ultrasonic-assisted dispersive liquid-liquid microextraction: Analysis of fosetyl-aluminum in fruit and vegetable samples
PublicationThis manuscript presents a new method for selective extraction and determination of fosetyl-aluminum in fruits and vegetable samples based on ultrasonic-assisted dispersive liquid-liquid microextraction method using ionic liquids (IL-UA-DLLME). A UV-Visible spectrophotometer was used for detection and quantification. Plants used for sample collection were grown under controlled conditions in a greenhouse. Central composite design...
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Computationally Efficient Multi-Objective Optimization of and Experimental Validation of Yagi-Uda Antenna
PublicationIn this paper, computationally efficient multi-objective optimization of antenna structures is discussed. As a design case, we consider a multi-parameter planar Yagi-Uda antenna structure, featuring a driven element, three directors, and a feeding structure. Direct optimization of the high-fidelity electromagnetic (EM) antenna model is prohibitive in computational terms. Instead, our design methodology exploits response surface...
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Phenolic compounds from Nerium oleander leaves: microwave assisted extraction, characterization, antiproliferative and cytotoxic activities
PublicationA microwave-assisted extraction (MAE) method was used for the extraction of phenolic compounds from Nerium oleander leaves. The influence of variables such as ethanol concentration, microwave power, irradiation time and liquid/solid ratio on polyphenol extraction was modelled using a second-order regression equation based on response surface methodology (RSM). The optimal conditions for MAE were: extraction solvent 35% ethanol...
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Hydrogen Production from Energy Poplar Preceded by MEA Pre-Treatment and Enzymatic Hydrolysis
PublicationThe need to pre-treat lignocellulosic biomass prior to dark fermentation results primarily from the composition of lignocellulose because lignin hinders the processing of hard wood towards useful products. Hence, in this work a two-step approach for the pre-treatment of energy poplar, including alkaline pre-treatment and enzymatic saccharification followed by fermentation has been studied. Monoethanolamine (MEA) was used as the...
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Effect of Tool Positioning Factors on the Strength of Dissimilar Friction Stir Welded Joints of AA7075-T6 and AA6061-T6
PublicationFriction Stir Welding (FSW) is a solid-state bonding technique. There are many direct and indirect factors affecting the mechanical and microstructural properties of the FSW joints. Tool offset, tilt angle, and plunge depth are determinative tool positioning in the FSW process. Investigating the effect of these factors simultaneously with other parameters such as process speeds (rotational speed and translational speed) and tool...
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Optimization of capillary isotachophoretic method for determination of major macroelements in blue honeysuckle berries (Lonicera caerulea L.) and related products
PublicationA reliable and repeatable isotachophoretic method for the simultaneous determination of K+, Na+, Ca2+, Mg2+ and ammonium in berries of different blue honeysuckle cultivars was developed. The usefulness of the complex-forming equilibria in determining the cations mentioned above was studied. The addition of 7.5 mM 18-crown-6 and 2 mM α-hydroxyisobutyric acid to sulfuric acid enhanced the separation capacity of the leading electrolyte....
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Multi-fidelity aerodynamic design trade-off exploration using point-by-point Pareto set identification
PublicationAerodynamic design is inherently a multi-objective optimization (MOO) problem. Determining the best possible trade-offs between conflicting aerodynamic objectives can be computationally challenging when carried out directly at the level of high-fidelity computational fluid dynamics simulations. This paper presents a computationally cheap methodology for exploration of aerodynamic design trade-offs. In particular, point-by-point...
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Data-Driven Surrogate-Assisted Optimization of Metamaterial-Based Filtenna Using Deep Learning
PublicationIn this work, a computationally efficient method based on data driven surrogate models is pro-posed for the design optimization procedure of a Frequency Selective Surface (FSS)-based filtering antenna (Filtenna). A Filtenna acts as a as module that simultaneously pre-filters unwanted sig-nals, and enhances the desired signals at the operating frequency. However, due to a typically large number of design variables of FSS unit elements,...
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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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Fast Multi-Objective Aerodynamic Optimization Using Sequential Domain Patching and Multifidelity Models
PublicationExploration of design tradeoffs for aerodynamic surfaces requires solving of multi-objective optimization (MOO) problems. The major bottleneck here is the time-consuming evaluations of the computational fluid dynamics (CFD) model used to capture the nonlinear physics involved in designing aerodynamic surfaces. This, in conjunction with a large number of simulations necessary to yield a set of designs representing the best possible...
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Quality control of cheese samples for the presence of natamycin preservative – A natural deep eutectic solvent (NADES) based extraction coupled with HPLC
PublicationA new protocol for the determination of natamycin – an antifungal agent used as a food preservative - in cheese samples – is described. This new method is based on a natural deep eutectic solvent (NADES) green extraction procedure. High-performance liquid chromatography (HPLC) was used for detection and quantification. NADESs with different molar ratios were evaluated for efficient and selective extraction. NADES made of thymol...
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Application of mechanistic and data-driven models for nitrogen removal in wastewater treatment systems
PublicationIn this dissertation, the application of mechanistic and data-driven models in nitrogen removal systems including nitrification and deammonification processes was evaluated. In particular, the influential parameters on the activity of the Nitrospira activity were assessed using response surface methodology (RSM). Various long-term biomass washout experiments were operated in two parallel sequencing batch reactor (SBR) with a different...
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New insights into modeling two-step nitrification in activated sludge systems – The effects of initial biomass concentrations, comammox and heterotrophic activities
PublicationIn this study, the conventional two-step nitrification model was extended with complete ammonia oxidation (comammox) and heterotrophic denitrification on soluble microbial products. The data for model calibration/validation were collected at four long-term washout experiments when the solid retention time (SRT) and hydraulic retention time (HRT) were progressively reduced from 4 d to 1 d, with mixed liquor suspended solids (MLSS)...
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Design of High-Performance Scattering Metasurfaces through Optimization-Based Explicit RCS Reduction
PublicationThe recent advances in the development of coding metasurfaces created new opportunities in realization of radar cross section (RCS) reduction. Metasurfaces, composed of optimized geometries of meta-atoms arranged as periodic lattices, are devised to obtain desired electromagnetic (EM) scattering characteristics. Despite potential benefits, their rigorous design methodologies are still lacking, especially in the context of controlling...
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Wyznaczanie odpływu ze zlewni niekontrolowanych Kanału Raduni podczas powodzi w 2001 r.
PublicationMetoda SCS (ang. Soil Conservation Service) pozwalająca wyznaczyć wysokość opadu efektywnego. Metoda geomorfologicznego hydrogramu jednostkowego do wyznaczenia hydrogramu odpływu ze zlewni niekontrolowanej. Aplikacja metody do sytuacji w zlewni Kanału Raduni na przykładzie powodzi z 2001 roku. Wyniki obliczeń dla potoków zasilających Kanał Raduni, odniesienie uzyskanych przepływów do dopływu z 2001 roku.
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Idea zastosowania sztucznej inteligencji w prognozowaniu wpływu drgań komunikacyjnych na odpowiedź dynamiczną budynków mieszkalnych
PublicationW poniższym artykule autorzy analizują wpływ drgań komunikacyjnych na budynki mieszkalne oraz metodykę pomiarową według PN-85 B-02170 [1]. Problemem badawczym jest opracowanie prostej metody prognozowania wpływu drgań na budynki mieszkalne w taki sposób, aby nie było konieczne przeprowadzanie pracochłonnych i kosztownych pomiarów polowych. W tym celu wykonano analizę przy użyciu algorytmów opartych na sztucznej inteligencji oraz...
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System Weryfikacji Autentyczności Podpisu Odręcznego
PublicationW referacie przedstawiono system statycznej i dynamicznej weryfikacji autentyczności podpisu odręcznego, składanego piórem biometrycznym, wyposażonym w 2 akcelerometry, 2 żyroskopy i 3 czujniki ścisku, na rezystancyjnej powierzchni dotykowej, łączącym się bezprzewodowo z urządzeniami komputerowymi. We wstępie przedstawiono architekturę sieciową wielomodalnego systemu biometrii. Przedstawiono warstwę sprzętową systemu weryfikacji...
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Oznaczanie tlenu – od metody Winklera do czujników enzymatycznych (Determination of oxygen – from Winkler Method to enzymatic sensor)
PublicationMonitoring of dioxygen levels is of utmost importance from the view-point of life processes, medical diagnostics, nutrition and chemical industries. In all these measurements both low and high levels of this element are important. The common methods for the determination of dioxygen are the Winkler method, Clark electrode and pulsoxymeters. A new, already strong field of research can be now recognized – the development of miniaturized...
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Asfalteny jako fazy stacjonarne w chromatografii cieczowej w normalnych układach faz
PublicationRozprawa doktorska dotyczy zbadania możliwości wykorzystania asfaltenów wydzielonych z: próżniowej pozostałości ropy naftowej, produktów jej utleniania i naturalnego asfaltu jako fazy stacjonarnej na powierzchni sorpcyjnej żelu krzemionkowego do rozdzielania nisko polarnych organicznych związków chemicznych w warunkach chromatografii cieczowej w normalnych układach faz, w odniesieniu do żelu krzemionkowego jako nośnika. Opracowano...
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Długie pociągi
PublicationWskazano, że przy wprowadzaniu długich pociągów pojawiają się możliwości, ale i ograniczenia różnej natury oraz problemy do rozwiązania. Inne w przypadku długich pociągów i inne w przypadku ciężkich pociągów. Pokazano długie pociągi, jako szansę na polepszenie bezpieczeństwa na drogach, poprzez ograniczenie na nich ruchu samochodów ciężarowych. Łatwiej będzie w praktyce realizować pomysł „Tiry na tory” Długie pociągi są szansą...
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Komputerowo wspomagana analiza elastycznych siłowników elektrostatycznych dla potrzeb implementacji w systemach mechatroniki
PublicationPrzeprowadzone badania naukowe rozpoczęto od szczegółowej analizy układu mechatronicznego dłoni robotycznych, powstałych na przestrzeni ostatnich 40 lat, w celu dokładnego rozpoznania ich głównych wymogów konstrukcyjnych i ograniczeń systemowych. Z uwagi na brak dostępnych narzędzi do symulacji omawianych siłowników, w rozprawie opracowano uniwersalne narzędzie – program do analizy numerycznej. U jego podstawy założono wykorzystanie...
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Oddziaływania taboru na mosty kolejowe przy zmiennych parametrach ruchu
PublicationW pracy poruszono zagadnienia związane z identyfikacją oraz modelowaniem układu dynamicznego most-pojazd ruchomy. Za element szczególnie istotny uznano czynnik obciążający. Opracowano i wdrożono metodykę identyfikacji cech dynamicznych rzeczywistego pojazdu szynowego. Eksperyment badawczy przeprowadzono dla jednostki trakcyjnej EN57, jednak nie ma żadnych ograniczeń w stosowaniu metody dla innego, konwencjonalnego taboru szynowego....
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Methodology for hospital design in architectural education
PublicationThe architecture of a hospital should be a response to strong user requirements. Recommendations on how to shape the environment of such facilities are highly complex, integrating guidelines from many fields of science. If contradictions between them exist, the designer is required to set priorities for spatial activities. This issue is particularly important during architectural education. The learning process should include projects...
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Wytwarzanie i modyfikacja powierzchni porowatych struktur tytanowych przeznaczonych na implanty
PublicationCelem pracy było wytworzenie stopu Ti-13Nb-13Zr z wykorzystaniem technologii selektywnego topienia laserowego (SLM) oraz jego biofunkcjonalizacja za pomocą utleniania mikrołukowego (MAO), a następnie określenie wpływu parametrów procesowych na właściwości otrzymanych materiałów pod kątem ich zastosowania na implanty. Oceniono wpływ napięcia, natężenia i czasu procesu MAO przeprowadzanego w elektrolicie zawierającym wapń i fosfor...
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Balance Between Creativity and Methodology in Software Projects
PublicationTaking into account trends of innovation in economy and increasing interest in applying creativity techniques in computer science, this paper focuses on relationship between creativity and methodology in software project. First, it extracts useful knowledge about creativity from creativity research. Then, it makes an attempt to combine creativity issues and dimensions with concepts from software project area. It presents also lessons...
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Quasi-Static Response
PublicationConcern for the quasi-static response of ship and offshore structures, as required for safety and serviceability assessments. Attention shall be given to uncertainty quantification of quasi-static load and response analysis approaches, and their limitations, including exact and approximate methods for derivation of different acceptance criteria.
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Methodology of Constructing and Analyzing the Hierarchical Contextually-Oriented Corpora
PublicationMethodology of Constructing and Analyzing the Hierarchical structure of the Contextually-Oriented Corpora was developed. The methodology contains the following steps: Contextual Component of the Corpora’s Structure Building; Text Analysis of the Contextually-Oriented Hierarchical Corpus. Main contribution of this study is the following: hierarchical structure of the Corpus provides advanced possibilities for identification of the...
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On the Bending of Multilayered Plates Considering Surface Viscoelasticity
PublicationWe discuss the bending resistance of multilayered plates taking into account surface/interfacial viscoelasticity. Within the linear surface viscoelasticity we introduce the surface/interfacial stresses linearly dependent on the history of surface strains. In order to underline the surface viscoelasticity contribution to the bending response we restrict ourselves to the elastic behaviour in the bulk. Using the correspondence principle...
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Methodology of the Morphometry Study on Baltic Herring
PublicationAcoustic techniques are used in the estimation of the abundance of Baltic herring. Investigations of the relationship between the Baltic herring individual target strength TS and the total fish length L, significant in the acoustic assessment, demonstrated its de-pendence on the study area location. It motivated the detailed analysis of the relationship between herring from the southern Baltic ICES Subdivisions 24, 25, and 26,...
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Transverse surface waves on a cylindrical surface with coating
PublicationWe discuss the propagation of transverse surface waves that are so-called whispering-gallery waves along a surface of an elastic cylinder with coating. The coating is modelled in the framework of linearized Gurtin–Murdoch surface elasticity. Other interpretations of the surface shear modulus are given and relations to so-called stiff interface and stiff skin model are discussed. The dispersion relations are obtained and analyzed.