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Wyniki wyszukiwania dla: VARIABLE KINEMATICS
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Photoluminescence Kinetics of YAG Crystals Activated with Ce, and Ce and Mg
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Kinetics and mechanism of the dehydrohalogenation of Ar2CHCX3 and Ar2CHCHX2 by strong N-bases
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Study of the Kinetics of Ammonia Synthesis and Decomposition on Iron and Cobalt Catalysts
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Kinetics studies of recrystallization process of metallic catalysts for ammonia synthesis
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Kinetics of photochromic reactions in a 10-membered dibenzoazo crown ether
PublikacjaPrzedstawiono rezultaty pomiarów kinetyki fotochromowych reakcji dla jednego z serii eterów koronowych zawierających fragment azobenzenowy. Badano 10-członową dibenzoazokoronę, która ulega odwracalnej foto i termicznej izomeryzacji, podobnie jak macierzysty azobenzen. Eksperymenty były prowadzone w matrycy pMMA. Reakcja izomeryzacji monitorowana była spektrofotometrycznie. Czynnik przedwykładniczy dla termicznej izomeryzacji cis-trans...
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A study of the kinetics of bismuth telluride synthesis by an oxide reduction method
PublikacjaThe kinetics of a reduction of bismuth and tellurium oxides in a hydrogen atmosphere, leading to the formation of thermoelectric bismuth telluride is investigated. The evaluation of the reaction kinetics was based on a thermogravimetric analysis performed in non-isothermal conditions. A non-parametric analysis method and the Friedman method were used for the evaluation of the data. Additionally, for a better understanding of the...
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Numerical solution of fractional neutron point kinetics in nuclear reactor
PublikacjaThis paper presents results concerning solutions of the fractional neutron point kinetics model for a nuclear reactor. Proposed model consists of a bilinear system of fractional and ordinary differential equations. Three methods to solve the model are presented and compared. The first one entails application of discrete Grünwald-Letnikov definition of the fractional derivative in the model. Second involves building an analog scheme...
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Kinetics of cross-linking processes of fast-curing polyurethane system
PublikacjaThis work focuses on the application of thermal analysis and kinetics investigations to analyze chemical processes during cross-linking of the complex fast-curing polyurethane system. Non-isothermal Differential Scanning Calorimetry (DSC) measurements were performed for both stoichiometric mixtures of polyol and isocyanate component and for mixture with large isocyanate excess. Isoconversional methods were used to calculate initial...
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Evaluation of selected diagnostic variables for the purpose of assessing the ageing effects in high-power IGBTs
PublikacjaPrzedstawiono metodę wyznaczania dwóch wskaźników diagnostycznych, które mogą być używane do oceny zużycia modułów IGBT dużej mocy. Proponowane podejście jest próbą zaadaptowania znanej z literatury metody laboratoryjnej do pracy bezpośrednio w układzie napędowym pojazdu trakcyjnego. Rozważane wskaźniki diagnostyczne to rezystancja cieplna między półprzewodnikiem a podstawą modułu oraz napięcie nasycenia kolektor-emiter IGBT....
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Do Existential Variables Mediate Between Religious-Spiritual Facets of Functionality and Psychological Wellbeing
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Unstructured finite-volume meshes for two-dimensional flow in variably saturated porous media
PublikacjaW pracy opisano rozwiązanie równania przepływu nienasyconego w ośrodkach porowatych z wykorzystaniem metody objętości skończonych. Przedstawiono różne sposoby tworzenia siatki numerycznej. Przeprowadzono analizę wpływu sposobu uśredniania współczynnika filtracji między sąsiednimi objętościami skończonymi na dokładność wyników.
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Approximate solutions of mixed problems for first order partial differential equations with deviated variables.
PublikacjaPraca traktuje o przybliżaniu rozwiązań klasycznych równańróżniczkowo-funkcyjnych cząstkowych pierwszego rzędu rozwiązaniamiukładów quasiliniowych równań różnicowych. Nowe podejście dorozwiązywania równań nieliniowych zawdzięczamy metodziequasilinearyzacji dla zagadnień początkowo - brzegowych z odchylonymargumentem. Dla przyrostów pochodnych funkcji danej zakładamy nieliniowe oszacowanie typu Perrona. Załączone są wyniki eksperymentów...
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Comparison of two methods for parameters selection of the proportional observer of induction motor state variables
PublikacjaArtykuł opisuje problemy odtwarzania prędkości obrotowej wału maszyny indukcyjnej przy wykorzystaniu estymatorów MRAS. Porównano dwie metody doboru wzmocnień obserwatora, analityczną i bazującą na algorytmach genetycznych
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Kinematyka jako odpowiedź na współczesną potrzebę tworzenia przestrzeni = KINEMATICS AS AN ANSWER TO THE CURRENT NEED TO CREATE A RE-CONFIGURABLE SPACE
PublikacjaPrzestrzeń re-konfigurowalna pojawiły się w sztuce i architekturze już w pierwszej połowie XX wieku jako forma odpowiedzi na na pytania, które stawia przed nią świat. Nasze życie i potrzeby zmieniają się niesamowicie dynamicznie. Postfordowski model społeczeństwa sprzyja generowaniu zjawisk, których jeszcze rok temu nie brano pod uwagę. Stąd architektura próbuje stanowić odpowiedź na problemy jeszcze niezaistniałe. Jedną z jej...
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Discussion of “Design Process of Asphalt Mixture Incorporating Compaction-Effort Variable” by Yining Zhang, Lijun Sun, and Dong Luo
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Variable-temperature X-ray diffraction study of structural parameters of NH---S hydrogen bonds in triethylammonium and pyridinium silanethiolates
PublikacjaHydrogen bonds in triethylammonium and pyridinium silanethiolate salts have been characterized by X-ray, FT–IR and NMR spectroscopies. DFT calculations reveal strongly asymmetric double-well minima at the potential energy curves of the studied compounds
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Cost‐efficient performance‐driven modelling of multi‐band antennas by variable‐fidelity electromagnetic simulations and customized space mapping
PublikacjaElectromagnetic (EM) simulations have become an indispensable tool in the design of contemporary antennas. EM‐driven tasks, for example, parametric optimization, entail considerable computational efforts, which may be reduced by employing surrogate models. Yet, data‐driven modelling of antenna characteristics is largely hindered by the curse of dimensionality. This may be addressed using the recently reported domain‐confinement...
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Variable‐fidelity modeling of antenna input characteristics using domain confinement and two‐stage Gaussian process regression surrogates
PublikacjaThe major bottleneck of electromagnetic (EM)-driven antenna design is the high CPU cost of massive simulations required by parametric optimization, uncertainty quantification, or robust design procedures. Fast surrogate models may be employed to mitigate this issue to a certain extent. Unfortunately, the curse of dimensionality is a serious limiting factor, hindering the construction of conventional data-driven models valid over...
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Knowledge-Based Expedited Parameter Tuning of Microwave Passives by Means of Design Requirement Management and Variable-Resolution EM Simulations
PublikacjaThe importance of numerical optimization techniques has been continually growing in the design of microwave components over the recent years. Although reasonable initial designs can be obtained using circuit theory tools, precise parameter tuning is still necessary to account for effects such as electromagnetic (EM) cross coupling or radiation losses. EM-driven design closure is most often realized using gradient-based procedures,...
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Elimination of Impulsive Disturbances From Stereo Audio Recordings Using Vector Autoregressive Modeling and Variable-order Kalman Filtering
PublikacjaThis paper presents a new approach to elimination of impulsive disturbances from stereo audio recordings. The proposed solution is based on vector autoregressive modeling of audio signals. Online tracking of signal model parameters is performed using the exponential ly weighted least squares algo- rithm. Detection of noise pulses an d model-based interpolation of the irrevocably distorted sampl es is realized using an adaptive, variable-order...
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Modelling a 6-dof manipulator using Matlab software
PublikacjaThis paper presents an alternative approach to modelling a revolute robot. The manipulator in question is Kuka KR 16-2. The main problem in robot modelling is a kinematic analysis. The revolute robot consist of six rotary joints (6-DOF) with base, shoulder, elbow and wirst. The kinematics problem is defined as a transformation from the cartesian space to the joint space. The Denavit- Hartenberg (D-H) model of representation was...
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Dark chocolate – a temptation harmful to health or a valuable component of diet?
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Chitosan as Valuable Excipient for Oral and Topical Carvedilol Delivery Systems
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The Most Valuable Global Brands and Condition of Economies: a Spatial Approach
PublikacjaResearch background: Brands are considered to be the most valuable asset of a company. Some of them achieve spectacular global results. The significance of global brands is proved by the fact that their value is often greater than the sum of all company’s net assets. Purpose of the article: The aim of this article is to highlight that brand value does not only create company’s value but also leverages economies. We claim that even though...
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The condition of economies. Do most valuable global brands matter?
PublikacjaResearch background: Brands are considered to be the most valuable asset of a company. Some of them achieve spectacular global results. The significance of global brands is proved by the fact that their value is often greater than the sum of all company’s net assets. Purpose of the article: The aim of this article is to highlight that brand value does not only create company’s value, but also leverages economies. The Authors claim...
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Energy and valuable organic products recovery from anaerobic processes
PublikacjaChapter 8 contains: Introduction, Energy balance in wastewater treatment plants and potential energy recovery, Potential valuable products recovery, Anaerobic processes focused on liquid products recovery; Anaerobic digestion (AD) processes focused on gaseous products recovery, Processes enhancing energy and valuable organic products recovery, Conclusions and perspectives. Anaerobic processes offer different pathways for the recovery...
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Sensitivity analysis of simple random beam models by means of Monte Carlo Methods using Variance Reductions Techniques
PublikacjaA probabilistic sensitivity analysis of two nonlinear bar structures is presented. The analysis is carried out on the basis of the Monte Carlo method. The imperfections of the structures and the applied loads are adapted as random variables. Based on all of the generated input variables, an output response of the system is sought. Afterwards, a coefficient responsible for the structure failure is calculated and the limit state...
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Kinetics of Flavoenzyme-Catalyzed Reduction of Tirapazamine Derivatives: Implications for Their Prooxidant Cytotoxicity
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Luminescence kinetics in silica gel doped with Tb3+ ions and ZnS:Mn2+ nanocrystals
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Kinetics and Mechanism of Potassium Persulphate/L-Serine Initiated Polymerization of Methylmethacrylate
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Novel investigation of pyrolysis mechanisms and kinetics for functional groups in biomass matrix
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Crystallization kinetics of poly(ethylene adipate) investigated by differential scanning calorimetry
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Cure kinetics of epoxy/MWCNTs nanocomposites: Isothermal calorimetric and rheological analyses
PublikacjaA combinatorial route has been applied in cure kinetics study of epoxy nanocomposites containing multi-walled carbon nanotubes (MWCNTs) based on differential scanning calorimetry and rheokinetic analyses under isothermal conditions. Pristine and amine-modified MWCNTs bearing primary and secondary amines were used at very low concentrations (0.1 and 0.3 wt.% based on epoxy weight). Model-free and model-fitting methods were applied...
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Cure kinetics of epoxy/MWCNTs nanocomposites: Nonisothermal calorimetric and rheokinetic techniques
PublikacjaNonisothermal calorimetric and isothermal rheokinetic analyses were used to study cure kinetics of epoxy/anhydride systems containing very low concentration of pristine and amine-functionalized multiwalled carbon nanotubes (MWCNTs). Isoconversional methods were applied in calorimetric modeling of cure kinetics. Eα vs. α dependency and autocatalytic nature of curing were identified for both types of nanocomposites by isoconversional...
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Nanocomposite of cement/graphene oxide – Impact on hydration kinetics and Young’s modulus
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Kinetics of aquation of [Co(ODA)(H2O)3] induced by Fe(III)
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Properties of a lithium solid electrolyte gas sensor based on reaction kinetics
PublikacjaW artykule przedstawiono zasadę działania, budowę i właściwości czujnika gazu na bazie elektrolitu stałego z mobilnymi jonami litu. Czujnik został przygotowany w technologii grubowarstwowej. Przedstawiono wyniki badań czujnika w mieszaninach gazów toksycznych.
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Kinetics of pollutants removal in hybrid treatment wetlands – Case study comparison
PublikacjaRecent years have seen an increasing interest in hybrid constructed wetland (HCW) systems for domestic sewage treatment. This paper is focused on kinetics of removal of the main pollutants occurring in wastewater i.e. organics expressed as chemical oxygen demand, biochemical oxygen demand and total nitrogen. The purpose of the article is to compare different HCW configurations in terms of mass removal rates (MRR) and removal rate...
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Thermal-Resistant Polyurethane/Nanoclay Powder Coatings: Degradation Kinetics Study
PublikacjaIn the present study, thermal degradation kinetics of polyurethane (PU) powder coatings reinforced with organo-modified montmorillonite (OMMT) was investigated. PU nanocomposites were prepared in different concentrations of 1, 3, and 5 wt.% of OMMT via the extrusion method. The microstructure of the nanocomposites was observed by scanning electron microscope (SEM) illustrating uniform dispersion of OMMT nano-clay platelets in the...
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Ab initio chemical kinetics of Isopropyl acetate oxidation with OH radicals
PublikacjaGlobal reactivity descriptors of isopropyl acetate (IPA) and thermo-kinetic aspects of its oxidation via OH radicals have been studied. Transition state theory (TST) was utilized to estimate the bimolecular rate constants. Ten oxidation pathways have been investigated, and all of them are exothermic. The potential energy diagram has been sketched using different pre- and post-reactive complexes for all reaction pathways. Rate coefficient...
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Genetic and lifestyle variables associated with homocysteine concentrations and the distribution of folate derivatives in healthy premenopausal women
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Set membership estimation of parameters and variables in dynamic networks by recursive algorithms with moving measurment window
PublikacjaW artykule rozważana jest łączna estymacja przedziałowa zmiennych i parametrów w złożonej sieci dynamicznej w oparciu niepewne modele parametryczne i ograniczoną liczbę pomiarów. Opracowany został rekursywny algorytm estymacji z przesuwnym oknem pomiarowym, odpowiedni dla monitorowania sieci on-line. Okno pomiarowe pozwala na stabilizowanie klasycznego algorytmu rekurencyjnego estymacji i znacznie poprawienie obcisłości estymat....
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PLS-Based and Regularization-Based Methods for the Selection of Relevant Variables in Non-targeted Metabolomics Data
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Fischer–Tropsch synthesis: Studies effect of reduction variables on the performance of Fe–Ni–Co catalyst
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A Comparison of Basic Training Variables in the Standard and Cambered Bar Bench Press Performed to Volitional Exhaustion
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Hydrological Excitations of Polar Motion Derived from Different Variables of Fgoals − g2 Climate Model
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Distribution of invasive Cylindrospermopsis raciborskii in the East-Central Europe is driven by climatic and local environmental variables
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Fast EM-Driven Nature-Inspired Optimization of Antenna Input Characteristics Using Response Features and Variable-Resolution Simulation Models
PublikacjaUtilization of optimization technique is a must in the design of contemporary antenna systems. Often, global search methods are necessary, which are associated with high computational costs when conducted at the level of full-wave electromagnetic (EM) models. In this study, we introduce an innovative method for globally optimizing reflection responses of multi-band antennas. Our approach uses surrogates constructed based on response...
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Fast tolerance-aware design optimization of miniaturized microstrip couplers using variable-fidelity EM simulations and re-sponse features
PublikacjaManufacturing 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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Comparison of the powers of energy losses in a variable capacity displacement pump determined without or with taking into account the power of hydraulic oil compression
PublikacjaPowers of energy losses in a variable capacity displacement pump are compared with or without taking into account the power of hydraulic oil compression. Evaluation of power of liquid compression in the pump was made possible by the use of method, proposed by the Author, of determining the degree of liquid aeration in the pump. In the method of determining the liquid aeration in the pump and of powers of volumetric losses of liquid...