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Search results for: optimization of chemical processes
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On measurements applied in scientific researches of microwave heating processes
PublicationPrzedstawiono trudności techniczne wykonywania pomiarów w systemach gdzie stosuje się duże poziomy mocy mikrofalowej. Omówiono zasadę pracy do badania procesu grzania mikrofalowego oraz wybrane problemy występujące przy realizacji takiego systemu. Uzasadniono celowość prowadzenia przedstawionych rodzajów pomiarów w badaniach procesów grzania mikrofalowego materiałów.
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Methods of electrochemical noise analysis for investigation of corrosion processes
PublicationKorozja elektrochemiczna może być oceniana za pomocą przpływu ładunków między korodującym metalem a elektrolitem. Zwykle, przpływ ładunku obserwuje się w układzie trzech elektrod jako fluktuacje prądu i napięcia (szumy elektrochemiczne). Na podstawie analizy szumów elektrochemicznych można wykrywać różne rodzaje korozji. Korozja jednorodna jest oceniana za pomocą wartości rezystancji polaryzacyjnej występującej między metalem a...
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Electrochemical noise analysis methods for the investigation of corrpsion processes
PublicationProcesy korozji mogą być badane przez obserwacje przepływu ładunków między elektrolitem a korodującą elektrodą metalową. Przepływy te są obserwowane jako fluktuacje prądu i napięcia nazywane szumem elektrochemicznym. Różne rodzaje procesów korozji mogą być identyfikowane za pomocą szumów elektrochemicznych. Szybkość korozji jednorodnej jest określana przez estymację rezystancji polaryzacji występującej między elektrolitem a metalem....
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Planning and simulation studies of cellular-type manufacturing processes
PublicationZaproponowano metodę i algorytmy projektowania struktur organizacyjnych systemów wytwarzania typu gniazdowego, z wykorzystaniem zdefiniowanych modeli zapisu wiedzy technologicznej i zasad grupowej obróbki przedmiotów. Wyznaczono wskaźniki efektywności procesu grupowego przebiegającego w systemach gniazdowych z rozmieszczeniem komórkowym oraz funkcjonalnym stanowisk wg przyjętych formuł analitycznych. Zawarto wyniki zrealizowanych...
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Organic light-emitting diodes. Principles, characteristics and processes.
PublicationJest to pierwsze monograficzne opracowanie zjawiska elektroluminescencji w organicznych ciałach stałych. W sześciu rozdziałach książki opisano między innymi wytwarzanie stanów wzbudzonych w wyniku rekombinacji ładunku, sposoby zaniku stanów wzbudzonych i ich rozkład przestrzenny, elektryczne i optyczne własności organicznych diod elektroluminescencyjnych oraz procesy warunkujące wydajne świecenie takich diod.
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Positron-annihilation monitoring of reduction processes in conducting glasses.
PublicationW publikacji podano wyniki badań metodą anihilacji pozytronów szkieł bizmutowo-krzemianowych, bizmutowo-germanianowych i ołowiowo-krzemianowych. Stwierdzono istnienie defektów wywołanych redukcją w atmosferze wodoru. Przeprowadzono analizę głębokości występowania defektów oraz ich rozmiarów.
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A Novel Trust-Region-Based Algorithm with Flexible Jacobian Updates for Expedited Optimization of High-Frequency Structures
PublicationSimulation-driven design closure is mandatory in the design of contemporary high-frequency components. It aims at improving the selected performance figures through adjustment of the structure’s geometry (and/or material) parameters. The computational cost of this process when employing numerical optimization is often prohibitively high, which is a strong motivation for the development of more efficient methods. This is especially...
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Anna Zielińska-Jurek dr hab. inż.
People2018 DSc in technical sciences in the field of chemical technology Chemical Faculty, Gdansk University of Technology, Title: “Functionalized titanium(IV) oxide as a photocatalyst for environmental purification” 2011 Ph. D. in technical sciences in the field of chemical technology Chemical Faculty, Gdansk University of Technology, Title of the dissertation:...
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Optimization of the UNRES Force Field by Hierarchical Design of the Potential-Energy Landscape. 3. Use of Many Proteins in Optimization
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Design and optimization of IIR digital filters with non-standard characteristics using continuous ant colony optimization algorithm
PublicationW pracy przedstawiono metodę projektowania i optymalizacji stabilnych filtrów cyfrowych IIR o niestandardowych charakterystykach amplitudowych, przy zastosowaniu ''mrówkowego'' algorytmu optymalizującego ACO. W proponowanej metodzie (nazwanej ACO-IIRFD), wprowadzono dynamiczne zmiany parametrów. Dzięki tym zmianom parametrów filtru cyfrowego możliwe jest uzyskanie małych odchyłek charakterystyk między założonymi i aktualnymi....
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Collision‐Aware Routing Using Multi‐Objective Seagull Optimization Algorithm for WSN‐Based IoT
PublicationIn recent trends, wireless sensor networks (WSNs) have become popular because of their cost, simple structure, reliability, and developments in the communication field. The Internet of Things (IoT) refers to the interconnection of everyday objects and sharing of information through the Internet. Congestion in networks leads to transmission delays and packet loss and causes wastage of time and energy on recovery. The routing protocols...
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Minimizing Greenhouse Gas Emissions From Ships Using a Pareto Multi-Objective Optimization Approach
PublicationTo confront climate change, decarbonization strategies must change the global economy. According to statements made as part of the European Green Deal, maritime transport should also become drastically less polluting. As a result, the price of transport must reflect the impact it has on the environment and on health. In such a framework, the purpose of this paper is to suggest a novel method for minimizing emissions...
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New materials and technologies used in chemical equipment design
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Chemical structures and physical properties of cured segmental polyurethanes
PublicationPrzedmiotem badań były poliuretany (PUR) segmentowe otrzymywane w dwuetapowej syntezie oligomerycznego α,ω-dihydroksy(adypinianu etylenowo-butylenowego) oraz dwóch różnych aromatycznych diizocyjanianów: 4,4'-diizocyjanianu difenylenometanu (MDI) albo MDI modyfikowanego diizocyjanianem karbodiimidu. Na etapie przedłużania łańcucha, oprócz typowo używanego do tego celu 1,4-butanodiolu, stosowano triol - 1,3-dihydroksy-2-(hydroksymetyleno)propan...
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Ionization of tocopherols and tocotrienols in atmospheric pressure chemical ionization
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Chemical reactivity and antimicrobial activity of N-substituted maleimides
PublicationZsyntezowano kilkanaście N-podstawionych maleimidów, zawierających w swojej strukturze podstawniki o różnej wielkości i polarności.Maleimidy o charakterze obojętnym wykazywały silny efekt przeciwgrzybowy; ich aktywność przeciwbakteryjna była zróżnicowana. Niską aktywność przeciwbakteryjną, ale wysoką aktywność cytostatyczną stwierdzono dla maleimidów o charakterze zasadowym. Reaktywność chemiczna i lipofilowość miały wpływ na aktywność...
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The influence of glycols on thermal stability and chemical structure of glycolysates
PublicationW pracy omówiono wpływ glikoli (etano-1,2-diolu - heksano-1,6-diolu) na właściwości termiczne oraz budowę chemiczną glikolizatów. Analizy przeprowadzono dla półproduktów wytworzonych w jednym stosunku masowym odpadowego poliuretanu do glikolu wynoszącego 10:1.
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The Influence of Waste Expanded Perlite on Chemical Durability of Mortars
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Mechanical properties of dissimilar welded joints for chemical tankers
PublicationArtykuł przedstawia właściwości mechaniczne złączy różnoimiennych stali typu duplex oraz austenitycznej typu 316L otrzymanych za pomocą spawania automatycznego łukiem krytym. Wykazano możliwość wykorzystania wysokowydajnej metody SAW w miejsce dotychczas stosowanych metod GTAW i GMAW do spawania blach zbiorników statków do przewozu chemikaliów. Pomimo obawy uzyskania nieodpowiednich struktur złączy okazało się, że spawanie stali...
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Chemical instability of the cobalt oxyhydrate superconductor under ambientconditions.
PublicationPrzedstawiono badania dyfrakcyjne i termograwimetryczne uwodnionego, sodowo-kobaltowego tlenku nadprzewodzącego: NaxCoO2 yH2O (y=1.4). Materiał ten jest niestabilny już w temperaturze pokojowej i przechodzi w nowo odkrytą fazę = 0.6.
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Determination of Chemical Diffusion Coefficient of Lithium Ions in Ceramics Derived from Pyrolysed Poly(1,2-dimethylsilazane) and Starch
PublicationThe apparent chemical diffusion coefficient Li+ (DappLI+) in pyrolysed poly(1,2-dimethylsilazane)/starch (PSN/S) (weight ratio: 30/70) ceramic anode composite is determined by galvanostatic intermittent titration technique (GITT). The electrode material composition is C6.00N0.14H0.47O0.12Si0.13. The calculated values of DappLI+, depend on the applied potential, vary from 10-14 to 10-9 [cm2/s]. The diffusion coefficient of lithium...
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Ireneusz Czarnowski Prof.
PeopleIRENEUSZ CZARNOWSKI is a graduate of the Faculty of Electrical Engineering at Gdynia Maritime University. He gained a doctoral degree in the field of computer science at Poznan University of Technology and a postdoctoral degree in the field of computer science at Wroclaw University of Science and Technology. Since 1998 is associated with Gdynia Maritime University, currently is a professor of computer science in the Department...
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The Chemical and Biological Properties of Nanohydroxyapatite Coatings with Antibacterial Nanometals, Obtained in the Electrophoretic Process on the Ti13Zr13Nb Alloy
PublicationThe risk of an early inflammation after implantation surgery of titanium implants has caused the development of different antimicrobial measures. The present research is aimed at characterizing the effects of nanosilver and nanocopper dispersed in the nanohydroxyapatite coatings, deposited on the Ti13Zr13Nb alloy, and on the chemical and biological properties of the coatings.The one-stage deposition process was performed by the...
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The Specific Nature of Chemical Composition of Water from Volcanic Lakes Based on Bali Case Study
PublicationThe research area was localized in the Indonesian Archipelago, at the latitude of eight and nine degrees S on the one of the Lesser Sunda group island provinces, Bali (563,3 km2). Two massive calderas (Mount Batur 1717 m above sea level.; Mount Sangiyang 2093 m above sea level) are one of the most prominent landforms in the chain of volcanic mountain ranges of the Bali Island. Lake Batur (17,18 km2) and Batur Spring (which are...
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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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Integration of the sulfate reduction and anammox processes for enhancing sustainable nitrogen removal in granular sludge reactors
PublicationThe Anammox and Sulfate Reduction Ammonium Oxidation processes were compared in two granular sequencing batch reactors operated for 160 days under anammox conditions. It was hypothesized that increasing the concentration of SO42− may positively influence the rate of N removal under anaerobic conditions and it was tested whether SO42− reduction and anammox occur independently or are related to each other. The cooperation of N-S...
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Rapid Simulation-Driven Multiobjective Design Optimization of Decomposable Compact Microwave Passives
PublicationIn this paper, a methodology for fast multiobjective optimization of the miniaturized microwave passives has been presented. Our approach is applicable to circuits that can be decomposed into individual cells [e.g., compact microstrip resonant cells (CMRCs)]. The structures are individually modeled using their corresponding equivalent circuits and aligned with their accurate, EM simulated...
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Optimization of biocorrosion resistance and mechanical properties of PM Ti–XAl–2Fe–3Cu alloys by response surface methodology
PublicationIn the current study, the biocorrosion resistance and mechanical properties of the Ti–XAl–2Fe–3Cu (wt%) (X = 6, 4, 2 wt%) alloy produced by powder compact extrusion of blended elemental powders were optimized by using the response surface methodology in order to gain the best combination of processing parameters. To run the optimization process, central composite design with three equal levels of oxygen, hydrogen and aluminum was...
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Chemical-Assisted Mechanical Lapping of Thin Boron-Doped Diamond Films: A Fast Route Toward High Electrochemical Performance for Sensing Devices
PublicationThere is an urgent need for an effective and economically viable increase in electrochemical performance of boron-doped diamond (BDD) electrodes that are used in sensing and electrocatalytic applications. Specifically, one must take into consideration the electrode heterogeneity due to nonhomogenous boron-dopant distribution and the removal of sp2 carbon impurities saturating the electrode, without interference in material integrity....
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On Rapid Design Optimization and Calibration of Microwave Sensors Based on Equivalent Complementary Resonators for High Sensitivity and Low Fabrication Tolerance
PublicationThis paper presents the design, optimization, and calibration of multivariable resonators for mi-crowave dielectric sensors. An optimization technique for circular complementary split ring reso-nator (CC-SRR) and square complementary split ring resonator (SC-SRR) is presented to achieve the required transmission response in a precise manner. The optimized resonators are manufac-tured using a standard photolithographic technique...
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Testing Stability of Digital Filters Using Optimization Methods with Phase Analysis
PublicationIn this paper, novel methods for the evaluation of digital-filter stability are investigated. The methods are based on phase analysis of a complex function in the characteristic equation of a digital filter. It allows for evaluating stability when a characteristic equation is not based on a polynomial. The operation of these methods relies on sampling the unit circle on the complex plane and extracting the phase quadrant of a function...
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Chemical structures, rheological and physical properties of biopolyols prepared via solvothermal liquefaction of Enteromorpha and Zostera marina biomass
PublicationIn this work, liquefied biomass from the Baltic Sea was used for the preparation of rigid polyurethane (PUR) foams. The biomass contained 10 wt% of Enteromorpha macroalgae and 90 wt% of Zostera marina seagrass characterized by a high content of cellulose. The influence of time, temperature and the type of solvent on the efficiency of the liquefaction process and properties of biopolyols was determined. Obtained materials were analyzed...
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Development of Local IDF-formula Using Controlled Random Search Method for Global Optimization
PublicationThe aim of the study is to present the effective and relatively simple empirical approach to rainfall Intensity-Duration-Frequency-formulas development, based on Controlled Random Search (CRS) for global optimization. The approach is mainly dedicated to the cases in which the commonly used IDF-relationships do not provide satisfactory fit between simulations and observations, and more complex formulas with higher number of parameters...
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Efficient Surrogate Modeling and Design Optimization of Compact Integrated On-Chip Inductors Based on Multi-Fidelity EM Simulation Models
PublicationHigh-performance and small-size on-chip inductors play a critical role in contemporary radio-frequency integrated circuits. This work presents a reliable surrogate modeling technique combining low-fidelity EM simulation models, response surface approximations based on kriging interpolation, and space mapping technology. The reported method is useful for the development of broadband and highly accurate data-driven models of integrated...
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Chemical composition of La-Sr-Ce-Ni-Ti ceramics material measured by XPS method
Open Research DataLa-Sr-Ce-Ni-Ti (LSCNT) based ceramics sample was manufactured by standard solid state reaction.Prepared powder was pressed into pilled and sintered in a furnace in air atmosphere for 10h. Annealing temperature was 1200 Celsius degree. To calculate chemical composition and determine valence states of the elements, X-Ray photoemission spectroscopy (XPS)...
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Multicriteria Optimization Approach to Design and Operation of District Heating Supply System over its Life Cycle
PublicationDistrict Heating (DH) systems are commonly supplied using local heat sources. Nowadays, modern insulation materials allow for effective and economically viable heat transportation over long distances (over 20 km). In the paper a method for optimized selection of design and operating parameters of long distance Heat Transportation System (HTS) is proposed. The method allows for evaluation of feasibility and effectivity of heat transportation...
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FLUID BED COATING OF MINITABLETS AND PELLETS WITH OPTIMIZATION OF THE PROCESS BASED ON TAGUCHI METHOD
PublicationSmall particles like pellets are coated in fluid bed systems. This method can be also feasible for minitablets but the selection of optimal process parameters is complicated. The aim of the research was to optimize the coating process for minitablets and to compare the conditions required for pellets. Minimum fluidization velocities (umf) for 2.0 and 2.5 mm minitablets and 0.7-0.8 mm or 1.0-1.25 mm pellets were determined experimentally....
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Multimodal Particle Swarm Optimization with Phase Analysis to Solve Complex Equations of Electromagnetic Analysis
PublicationIn this paper, a new meta-heuristic method of finding roots and poles of a complex function of a complex variable is presented. The algorithm combines an efficient space exploration provided by the particle swarm optimization (PSO) and the classification of root and pole occurrences based on the phase analysis of the complex function. The method initially generates two uniformly distributed populations of particles on the complex...
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A design framework for rigorous constrained EM-driven optimization of miniaturized antennas with circular polarization
PublicationCompact radiators with circular polarization are important components of modern mobile communication systems. Their design is a challenging process which requires maintaining simultaneous control over several performance figures but also the structure size. In this work, a novel design framework for multi-stage constrained miniaturization of antennas with circular polarization is presented. The method involves sequential optimization...
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Application of the Optimization Methods to the Search of Marine Propulsion Shafting Global Equilibrium in Running Condition
PublicationFull film hydrodynamic lubrication of marine propulsion shafting journal bearings in running condition is discussed. Considerable computational difficulties in non-linear determining the quasi-static equilibrium of the shafting are highlighted. The approach using two optimization methods (the particle swarm method and the interior point method) in combination with the specially developed relaxation technique is proposed to overcome...
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Application of chiral chromatography for enantiomeric separation of currently used pesticides from various chemical groups
PublicationChiral pesticides account for more than 25 % of currently used pesticides and this ratio is still increasing. According to the number of chiral centers in the structure, a pesticide may consist of two or multiple enantiomers or stereoisomers. Studies into the stereoselective behaviour of pesticides started in the early 1990s and most research efforts focused on understanding the environmental fate and effects of these pesticides....
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Amperometric sensing of chemical oxygen demand at glassy carbon and silicon electrodes modified with boron-doped diamond
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Fast tolerance-aware design optimization of miniaturized microstrip couplers using variable-fidelity EM simulations and re-sponse features
PublicationManufacturing tolerances and other types of uncertainties may considerably affect operation and performance of microwave components and systems. Quantification of these effects is therefore an important part of the design process. It is even more important to obtain designs whose sensitivity to parameter deviations is reduced as much as possible. All of these require statistical analysis carried out at the level of electromagnetic...
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Local structural and chemical ordering of nanosized Pt(3±δ)Co probed by multiple-scattering x-ray absorption spectroscopy
PublicationThis work reports a detailed investigation of the local structure and chemical disorder of a Pt(3±δ)Co thin film and Pt(3±δ)Co nanoparticles. We have used a combination of techniques including x-ray absorption spectroscopy (XAS), x-ray diffraction (XRD), and high-resolution transmission electron microscopy (TEM). The important effect of chemical ordering on pair and three-atom configurations has been studied using computer simulations...
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Balanced Spider Monkey Optimization with Bi-LSTM for Sustainable Air Quality Prediction
PublicationA reliable air quality prediction model is required for pollution control, human health monitoring, and sustainability. The existing air quality prediction models lack efficiency due to overfitting in prediction model and local optima trap in feature selection. This study proposes the Balanced Spider Monkey Optimization (BSMO) technique for effective feature selection to overcome the local optima trap and overfitting problems....
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