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Search results for: FEMTOSECOND PHENOMENA
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Cavitation Erosion – Phenomenon and Test Rigs
PublicationThe cavitation and cavitation erosion phenomenon have been shortly presented. The main four types of test rigs to investigate the cavitation erosion resistance have been shown. Each type of test design is described and an example of a design is shown. A special attention has been payed to the designs described in the International ASTM Standards: a vibratory design and a cavitating jet cell. There was shown that the design of a...
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Metal dusting phenomena of 501 AISI furnace tubes in refinery fractional distillation unit
PublicationThe purpose of this investigation was to conduct the failure analysis of 501 AISI furnace tubes places before distillation column in fractional distillation unit. The investigated furnace tubes were planned to work for ten years however after just two years of exploitation <30% of the material left. The observed corrosion process had the intense and complex character. The well-adhered shiny black deposits and deep, round pits were...
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Regulatory B Cells Involvement in Autoimmune Phenomena Occurring in Pediatric Graves’ Disease Patients
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Surface phenomena in discotic liquid crystals investigated using polarized FTIR transmission spectroscopy
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Parallel simulations of electrophysiological phenomena in myocardium on large 32 and 64-bit Linux clusters.
PublicationW pracy podjęto badania i przeprowadzono symulacje zjawisk elektrofizjologicznych w mięśniu sercowym z wykorzystaniem wytworzonego w tym celu oprogramowania równoległego opartego na MPI. Zaimplementowano i zbadano ulepszenia kodu prowadzące do uzyskania dobrej skalowalności oraz przeprowadzono testy wydajności na najnowszych 32 i 64-bitowych klastrach linuksowych. Praca stanowi próbę równoległej implementacji znanego podejścia...
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Standing Acoustic Waves and Relative Nonlinear Phenomena in a Vibrationally Relaxing Gas-Filled Resonator
PublicationStanding acoustic waves in one-dimensional resonator filled with vibrationally relaxing gas, are studied. Two regimes of excitation of molecular vibrational degrees of freedom are considered, equilibrium and nonequilibrium. The acoustic energy enlarges with time in the non-equilibrium regime and decreases otherwise before formation of discontinuity. After that, it decreases due to nonlinear absorption and tends to zero in equilibrium...
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THE POSSIBILITIES OF ESTIMATING THE RELIABILITY OF SHIP PIPELINES’ ELEMENTS INCLUDING DESTRUCTIVE PHENOMENA ACTING ON THEM
PublicationIn the article an approach to the problem of estimating reliability data based on physical models is proposed. The possibility of reliability assessment for selected elements of ship pipelines, based on the recognition of the destructive physical phenomena taking place in them, is discussed. To do this, an overview of these phenomena has been made. In addition, a preliminary review of existing measures of destruction of materials...
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Case studies of resonance phenomena in high voltage overhead power lines with shunt reactors
PublicationMisguided design of the towers of power transmission lines can lead to serious problems such as voltage asymmetry, overvoltages, electric arc extinction difficulties or resonance – in case of double circuit line with shunt reactors. The paper points out those threats on example of 400 kV double circuit overhead transmission line with shunt reactors.
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Artificial Neural Network in Forecasting the Churn Phenomena Among Costumers of IT and Power Supply Services
PublicationThis paper presents an attempt to use an artificial neural network to investigate the churn phenomenon among the customers of a telecommunications operator. An attempt was made to create a data model based on the customer lifetime value (CLV) rather than on activity alone. A multilayered artificial neural network was used for the experiments. The results yielded a 99% successful identification rate for customers in no danger of...
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Predicting Ice Phenomena in a River Using the Artificial Neural Network and Extreme Gradient Boosting
PublicationForecasting ice phenomena in river systems is of great importance because these phenomena are a fundamental part of the hydrological regime. Due to the stochasticity of ice phenomena, their prediction is a difficult process, especially when data sets are sparse or incomplete. In this study, two machine learning models—Multilayer Perceptron Neural Network (MLPNN) and Extreme Gradient Boosting (XGBoost)—were developed to predict...
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Thermal and Hydrodynamic Phenomena in the Stagnation Zone — Impact of the Inlet Turbulence Characteristics on the Numerical Analyses
PublicationOne of the methods of heat transfer enhancement is utilization of the turbulent impinging jets, which were recently applied, for example, in the heat exchangers. Their positive impact on the heat transfer performance was proven, but many questions related to the origin of this impact are still unanswered. In general, the wall-jet interaction and the near-wall turbulence are supposed to be its main reason, but their accurate numerical...
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Improving osteoblasts cells proliferation via femtosecond laser surface modification of 3D-printed poly-ε-caprolactone scaffolds for bone tissue engineering applications
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Study washboarding phenomenon in frame sawing machines
PublicationPraca dotyczy zjawiska washboarding cechującego się powstawaniem na piłowanej powierzchni sinusoidalnego profilu w przekroju poprzecznym i wzdłużnym. Wzór ten jest efektem drgań poprzecznych piły. Przedstawiono wyniki analiz teoretycznych oraz badań eksperymentalnych, w których wykazano, że zjawisko w przypadku pilarek ramowych jest efektem drgań wymuszonych brzeszczotu oraz regeneracji powstałej fali pierwotnej.
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Study washboarding phenomenon in fame sawing machines
PublicationPraca dotyczy zjawiska washboarding cechującego się powstawaniem na piłowanej powierzchni sinusoidalnego profilu w przekroju poprzecznym i wzdłużnym. Wzór ten jest efektem drgań poprzecznych piły. Przedstawiono wyniki analiz teoretycznych oraz badań eksperymentalnych, w których wykazano, że zjawisko w przypadku pilarek ramowych jest efektem drgań wymuszonych brzeszczotu oraz regeneracji powstałej fali pierwotnej.
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Bound entanglement for continuous variables is a rare phenomenon
PublicationWykazano, że splątanie związane w przypadku zmiennych ciągłych jest rzadkimfenomenem. W szczególności pokazano, że zbiór stanów niedestylowalnych jestnigdzie gęsty w zbiorze wszystkich stanów kwantowych. Poddano dyskusji splą-tanie związane w kontekście liczby Schmidta.
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The Urbanity Phenomenon – Tradition and New Cultural Iterations
PublicationCities that have managed to survive and rebuild lost urbanity do not close themselves towards new forms that are largely generated by culture. People are increasingly organized around common, local goals. They want to live in cities that open themselves up to differences, with culture as a tool for the revitalization of urbanity. Flexible management methods, tailored to the context and new needs, are therefore emphasized. Nowadays,...
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The use of terrestrial laser scanning in monitoring and analyses of erosion phenomena in natural and anthropogenically transformed areas
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Ion Exchange And Related Phenomena In Glass Periodical GRIN Matrices During The Mosaic-Assembling Technology
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Vivedenna dosovih vod u grunt = The rain - water management solutions basedon the seepage phenomena
PublicationWprowadzanie wód opadowych do gruntu. Rozwiązania o małej przepustowości, głównie do zastosowania w budynkach jednorodzinnych.
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Considerations about the applicability of the Reynolds equation for analyzing high-speed near field levitation phenomena
Publicationequation for analyzing near field levitation (NFL) phenomena. Two separate approaches were developed, experimentally verified, and applied to meet the research objective. One was based on the Reynolds equation and the other was based on general conservation equations for fluid flow solved using computational fluid dynamic (CFD). Comparing the calculation results revealed that, for certain operating conditions, differences in the...
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Two-phase flow phenomena assessment in minichannels for compact heat exchangers using image analysis methods
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The Co-Culture of Staphylococcal Biofilm and Fibroblast Cell Line: The Correlation of Biological Phenomena with Metabolic NMR1 Footprint
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Frequency and phase analysis of daily reprocessed solutions from selected EPN stations relating to geological phenomena,
PublicationThe main assumption of this research was to check and verify the behaviour of a few EPN (European Permanent Network) stations on both sides of the Teisseyre-Tornquist zone (T-T zone), which is located on Polish territory and crosses Poland almost in half. The selected EPN stations’ time series were a subject of frequency and phase analysis. The main purpose of the research was to verify if there is any correspondence between stations...
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Open Dialogue Approach – about the phenomenon of Scandinavian Psychiatry
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Evaluation of macroeconomic variables influencing the phenomenon of bankruptcies in Poland
PublicationW rozdziale tym przedstawiono ocenę zjawiska upadłości przedsiębiorstw w Polsce w latach 1991-2005. Autor przeanalizował wskaźnik natężenia upadłości oraz ilość wniosków upadłościowych. Oceniono również wpływ czynników makroekonomicznych na kształtowanie się zjawiska upadłości firm w Polsce. W rozdziale tym autor również przedstawił opracowane przez niego modele ekonometryczne prognozowania zarówno natężenia, jak i ilości wniosków...
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Networks Externalities as Social Phenomenon in the Process ICT Diffusion.
PublicationThis paper is designed to fill the gap in knowledge that we have identified regarding the process of diffusion of information and communication technologies and emerging network effects that significantly enhance spread of these technologies. We contribute to the present state of the art by examining the process of ICT diffusion in 50 countries, which in 2015 achieved highest ICT penetration rates.
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The model of photovoltaic phenomenon in thin inhomogeneously organic film
PublicationW pracy przedstawiono model zjawiska fotowoltaicznego w obecności gradientu pułapek nośników ładunku. Zakładając, że długość dyfuzji ekscytonów związana jest z koncentracją pułapek, wykazano, że napięcie fotowoltaiczne silnie zależy od gradientu koncentracji pułapek.
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An Experimental and Numerical Analysis of Water Hammer Phenomenon in Slurries
PublicationThe analysis of slurry transportation in pressure pipelines is important both from practical and theoretical point of view. Due to the nature of the medium, the number of problems arising in the course of design, operation, measurements and mathematical modeling is much higher compared to the cases where the flowing liquid is homogeneous. The equations describing the flow are more complex, and higher number of the parameters is...
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Structural changes of a simple peptide—Trpzip-1—in aqueous solutions and the corresponding hydration phenomena under the influence of temperature
PublicationTrpzip-1, a simple β-hairpin, is a rare example of peptide with stable secondary structure and can be a convenient model to study temperature-related processes that potential prion or amyloid proteins undergo. Although its sequence is simple, the exact processes which the peptide undergoes in aqueous solutions are quite complex and not well understood. The selection of well-established experimental (DSC, FTIR) and theoretical methods...
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Volterra series usefulness in modelling of the time-domain cross-talk phenomena in coupled microstrip lines with nonlinear termination
PublicationW pracy przedyskutowano możliwość wykorzystania szeregów Volterry do analizy zjawiska przesłuchu w sprzężonych liniach mikropaskowych z nieliniowym obciążeniem. Apracowano algorytm metody, zaś uzyskane wyniki numeryczne zweryfikowano poprzez porównania z wynikami badań eksperymentalnych linii obciążonych w torze transmisyjnym diodą Schottky'ego.
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Vivedenna dosovih vod u grunt = The rain - water management solutions basedon the seepage phenomena cz.2
PublicationWprowadzanie wód opadowych do gruntu. Rozwiązania o dużej przepustowości, do użycia w odwadnianiu dużych powierzchni.
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Chemometric determination of solute-affected solvent vibrational spectra as a superior way of information extraction on solute solvation phenomena
PublicationW pracy zaprezentowano dwie chemometryczne metody wyznaczania widm zaburzonych rozpuszczalnika oraz liczby cząsteczek zaburzonych, na podstawie zmierzonych serii wibracyjnych widm FT-IR roztworów substancji. Pierwsza z metod została stworzona na podstawie Namiarowej Analizy Faktorowej (ang. Target Factor Analysis). Druga z nich wykorzystuje algorytm izolacji widm czystych składników z serii widm mieszanin. Działanie obu metod zostało...
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Hula-hooping as an unusual cause of Koebner phenomenon in a psoriatic patient
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Phenomenon of Mobbing as IT Users Burnout Premises. Insight from Poland
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e-Commerce Websites and the Phenomenon of Dropshipping: Evaluation Criteria and Model
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The Effect of the Phenomenon of “Spectrum Leakage” on the Measurement of Power Quality Parameters
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Emotion Recognition - the need for a complete analysis of the phenomenon of expression formation
PublicationThis article shows how complex emotions are. This has been proven by the analysis of the changes that occur on the face. The authors present the problem of image analysis for the purpose of identifying emotions. In addition, they point out the importance of recording the phenomenon of the development of emotions on the human face with the use of high-speed cameras, which allows the detection of micro expression. The work that was...
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Occurrence of antimicrobial resistant bacteria in environment and the statistical analysis of this phenomenon
PublicationIntroduction: In this study the occurrence of antimicrobial resistance patterns among fecal indicators (Escherichia coli and Enterococcus spp.) was analyzed in water and wastewater samples. The trends in antimicrobial resistance were analyzed using basic statistical methods. Methods: Samples were obtained from two local watercourses (Oliwski Stream and Reda River) as well as from the wastewater treatment plant (WWTP) Gdansk - Wschod....
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A Critical Reanalysis of Uncontrollable Washboarding Phenomenon in Metal Band Sawing
PublicationThe article analyzes the cutting process of hard bars. Investigations conducted in industrial conditions demonstrated the presence of surface errors in the machined workpieces in the form of washboard patterns. The purpose of this study was to analyze the results of cutting on band sawing machines with different band saw blades. The cutting processes were conducted on three different horizontal band sawing machine types. Analyzed...
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Bioavailability of Tannins and Other Oligomeric Polyphenols: a Still to Be Studied Phenomenon
PublicationPurpose of Review Polyphenols are a group of plant secondary metabolites characterized with the presence ofmultiples of phenol structural units. Tannins are plant originated phenolic substances, which play an important role in plant defense system as well as have found applications in medicine, industry, and other fields of human activity. Despite these, the mechanisms of bioavailability of these substances are poorly studied and...
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Local Conformation and Cocrystallization Phenomena in Renewable Diaminoisoidide-Based Polyamides Studied by FT-IR, Solid State NMR, and WAXD
PublicationBiobased polyamides synthesized from diaminoisoidide (DAII), 1,4-diaminobutane, and sebacic acid are investigated by FT-IR, 13C{1H} magic-angle spinning/cross-polarization (CP/MAS) NMR spectroscopy, and WAXD. Their molecular conformation and mobility undergo distinct changes as a function of temperature and diaminoisoidide content in the compositions. The presence of randomly distributed diaminoisoidide (DAII) in the polyamides...
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Modeling of Electrodynamic Phenomena in an Ultra-Rapid Inductive–Dynamic Actuator as Applied to Hybrid Short-Circuit Breakers - A Review Study
PublicationThis article is a study of the research development of electrodynamic phenomena occurring in ultra-fast electrodynamic drives. These types of linear drives are among the fastest, not only because of the huge accelerations achieved, but, above all, because of the extremely short reaction time. For this reason, electrodynamic drives are used in hybrid short-circuit breakers. The phenomena occurring in this type of drive are actually...
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CLAY MINERALS – MINERALOGY AND PHENOMENON OF CLAY SWELLING IN OIL & GAS INDUSTRY
PublicationAmong the minerals found in the earth's crust, clay minerals are of the widest interest. Due to the specific properties such as plasticity, absorbing and catalytic properties clay minerals are used in many industries (oil & gas, chemistry, pharmacy, refractory technology, ceramics etc.). In drilling, a phenomenon of swelling clays is frequently observed. It has an important impact on the cementing quality. During the last few decades...
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LINEAR CHARACTERISTICS OF THE SLOSHING PHENOMENON FOR THE PURPOSE OF ON-BOARD SHIP'S STABILITY ASSESSMENT
PublicationThe paper presents results of experimental research and numerical simulations of the sloshing phenomenon. The research was focused on computation of the heeling moment affecting stability of a vessel. The proposed linearisation enables application of the results to the assessment of the ship's stability. The dependence of the heeling moment upon localisation of a tank in the ship's hull is analysed. The heeling moment obtained...
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Investigation of some magnetospheric phenomena of geomagnetic storm on March 17, 2013 based on observations from GNSS and NOAA-15 satellite
PublicationSubstantial variations of magnetospheric electron fluxes of low and intermediate energies at an altitude of ~ 800 km at different phases of the geomagnetic storm were investigated. The ionosphere and plasmasphere response was analyzed using TEC variation maps over the Central Europe. A concept of the connection of TEC variations above the Central Europe and spatially inhomogeneous fluxes of energetic particles is being proposed.
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The phenomenon of HbA1c stability and the risk of hypoglycemia in long-standing type 1 diabetes
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Flip-Flop Phenomenon in Epidural Sufentanil Pharmacokinetics: A Population Study in Children and Infants
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Experimental verification of natural convective heat transfer phenomenon from isothermal cuboids
PublicationArtykuł przedstawia wyniki badań eksperymentalnych konwekcyjnej wymiany ciepła od powierzchni izotermicznego prostopadłościanu o stosunkowo dużych rozmiarach (t.j. 1.5 m x1 m x 0.5 m). Celem tych badań było otrzymanie wyników, które można by porównać z otrzymanymi dla obiektu w mniejszej skali i prezentowano we wcześniejszych doniesieniach (Int. J. Heat Mass Transfer 46 (2003) 2169-2178). Rozwiązanie eksperymentalne przeprowadzono...
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Experimental and theoretical study of flow boiling and dryout phenomenon of ethanol in vertical minitubes
PublicationW ramach przeprowadzonych prac zaadoptowano istniejące stanowisko do badań laminarnej konwekcji wymuszonej, wrzenia w przepływie oraz wysychania filmu cieczy na ściance kanału wykorzystując etanol jako płyn roboczy. Przeprowadzono systematyczne badania wrzenia w przepływie dla dwóch średnic rur, tj. 1.15mm i 2.3mm. W badaniach wykorzystano najnowsze osiągnięcia z zakresu technik termowizyjnych celem znalezienia dokładnej lokalizacji...
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Water related esthetics - the phenomenon of new structure in the post industrial shipyard areas
PublicationDirection of the main movements that are made in the European cities determines not only structural but also an esthetic changes. Paper follows the topic of visual diversity of post industrial waterfront cities and it’s relation to the local identity and cultural changes that are provided. Reshaping of the cities continuously proceed. Are those changes related with industrial shipyard districts only economical and spatial or also...