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THE STUDY OF WATER POLLUTION OF THE LOWER VISTULA RIVER BY PLASTIC PARTICLES
PublikacjaSince the beginning of widespread use of plastic its consumption and production has been constantly increasing. As a result of human activity part of waste ends up in our environment and is deposited in each of the elements of the biosphere. These impurities can be in the form of large elements, small particles fragmented to macroscopic level (pellets, facial scrub grains) and the microparticles visible under a microscope. Particularly...
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Przegląd systemów ładowania elektrycznych osobowych pojazdów i koncepcja dwukierunkowej ładowarki pokładowej
PublikacjaAktualnie trwa intensywny rozwój pojazdów elektrycznych (EV) i hybrydowych typu plug-in (PHEV) z pokładowymi bateriami akumulatorów. Badania w tej dziedzinie skupiają się na maksymalizowaniu sprawności oraz minimalizowaniu masy i objętości systemów ładowania baterii. W artykule przedstawiono podział systemów ładowania osobowych pojazdów typu EV/PHEV. Opisano systemy ładowania przewodowego z podziałem na ładowarki pokładowe i zewnętrzne, systemy...
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Visible light-induced photocatalytic reaction of gold-modified titanium(IV) oxide particles: action spectrum analysis
PublikacjaAnalizy spektrum działania wykazały, ze wzbudzenie powierzchniowego plazmonu złota inicjuje utlenianie 2-propanolu w świetle widzialnym w napowietrzonej zawiesinie tlenku(IV) tytanu zmodyfikowanego zlotem. Badania przeprowadzone z użyciem światła polichromatycznego wykazały, ze szybkość reakcji foto-utleniania zależy od właściwości tlenku(IV) tytanu, takich jak rozmiar ziaren, pola powierzchni właściwej, formy krystalicznej (anataz...
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Wielopoziomowe modelowanie ruchu - koncepcja i doświadczenia praktyczne
PublikacjaDoświadczenia z ostatnich lat na obszarze województwa pomorskiego wskazują, że na obszarze województwa pomorskiego stosowane są różne narzędzia prognozowania i analiz transportowych. Stosowane modele są niekompatybilne, opracowywane przy innych założeniach i co najgorzej produkowane prognozy i wyniki analiz znacznie różnią się między sobą. Biorą to pod uwagę Katedra Inżynierii Drogowej Politechniki Gdańskiej wyszła z inicjatywą...
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Modelling and Analysis of the Positioning Accuracy in the Loading Systems of Mobile Cranes
PublikacjaIn this work, the authors analyse the influence of the order and range of sequential movements of a crane's working members on the accuracy of the final cargo positioning. The analysis was conducted on the basis of a specially developed method in which the authors proposed the introduction of a geometrical indicator of positioning the load in the intermediate positions (after completing each movement sequence) and in the target...
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Concentration and sources of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in surface soil near a municipal solid waste (MSW) landfill
PublikacjaDue to a continuous demand of land for infrastructural and residential development there is a public concern about the condition of surface soil near municipal solid waste landfills. A total of 12 surface (0–20 cm) soil samples from a territory near a landfill were collected and the concentration of 16 PAHs and 7 PCB congeners were investigated in these samples. Limits of detection were in the range of 0.038–1.2 μg/kg for PAHs...
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Towards improved energy efficiency of future smart ships by application of advanced CFD simulations – case study
PublikacjaThe international trade plays crucial role in today’s globally developed world’s economy. Many people are unaware of the unimaginable volume of cargo being transported every year by oceans and seas. For most of the time invisible from land the shipping industry preserves its strong position of the most cost-efficient and environmental friendly mean of transport. However during last years the shipping industry is under great pressure...
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Determination of ionic conductivity in the Bi-Si-O and Pb-Si-O glasses
PublikacjaImpedance spectroscopy measurements in various gas atmospheres were carried out in order to explain the doubts about the type of carriers and the mechanism of electrical conductivity in Bi-Si-O and Pb-Si-O glasses. In bismuth silicate glass, a typical ionic conductivity with oxygen ions as charge carriers was observed. The level of electrical conductivity of the glass at 400 °C was 5 × 10−8 S·cm−1 , with the activation energy of...
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Analiza przyczyn zużywania się (uszkadzania) szyn w zależności od warunków techniczno – eksploatacyjnych toru
PublikacjaDiagnostyka nawierzchni kolejowej jest istotnym elementem składowym czynników wpływających na poprawę stanu technicznego infrastruktury kolejowej w Polsce. Monitorowanie zmian zachodzących na powierzchni tocznej szyn jest bardzo ważnym elementem w kontekście poziomu bezpieczeństwa przewozów prowadzonych transportem szynowym. W artykule przedstawiono niektóre z czynników wpływające na proces degradacji powierzchni tocznej szyn w...
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ANALYSIS OF IMPACT of SHIP model parameters on changes of control quality index in ship dynamic positioning system
PublikacjaIn this work there is presented an analysis of impact of ship model parameters on changes of control quality index in a ship dynamic positioning system designed with the use of a backstepping adaptive controller. Assessment of the impact of ship model parameters was performed on the basis of Pareto-Lorentz curves and ABC method in order to determine sets of the parameters which have either crucial, moderate or low impact on objective...
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Disaster-Resilient Routing Schemes for Regional Failures
PublikacjaLarge-scale natural disasters can have a profound effect on the telecommunication services in the affected geographical area. Hence, it is important to develop routing approaches that may help in circumventing damaged regional areas of a network. This prompted the development of geographically diverse routing schemes and also of disaster-risk aware routing schemes. A minimum-cost geodiverse routing, where a minimum geographical...
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Effective Permeability of Multi Air Gap Ferrite Core 3-Phase Medium Frequency Transformer in Isolated DC-DC Converters
PublikacjaThe magnetizing inductance of the medium frequency transformer (MFT) impacts the performance of the isolated dc-dc power converters. The ferrite material is considered for high power transformers but it requires an assembly of type “I” cores resulting in a multi air gap structure of the magnetic core. The authors claim that the multiple air gaps are randomly distributed and that the average air gap length is unpredictable at the...
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Propagation Characteristics of Partial Discharges in an Oil-Filled Power Transformer
PublikacjaPower transformers are among the most important assets in the power transmission and distribution grid. However, they suffer from degradation and possible faults causing major electrical and financial losses. Partial discharges (PDs) are used to identify the insulation health status and their degradation level. PDs are incipient, low-magnitude faults caused by localized dielectric breakdown. Those activities emit signals in many...
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Szybkie uziemniki do ograniczania skutków zwarć łukowych w okrętowych rozdzielnicach SN
PublikacjaW artykule scharakteryzowano moc i napięcie łuku, jak również przedstawiono model termodynamiczny służący do obliczania ciśnienia i temperatury gazów w otoczeniu łuku zwarciowego. Przedstawiono przykładowy układ elektrowni okrętowej i zasilania najważniejszych odbiorników na statku do przewozu gazu ziemnego w stanie ciekłym. Na podstawie parametrów prądnic i silników odbiorników zasilanych z rozdzielnicy głównej obliczono prądy...
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Isolation and characterization of Acid Soluble Collagen from the Skin of African Catfish (Clarias gariepinus), Salmon (Salmo salar) and Baltic cod (Gadus morhua)
PublikacjaAcid-soluble collagen (ASC) from the fish skin of African catfish (Clarias gariepinus), Salmon (Salmo salar) and Baltic cod (Gadus morhua) was extracted and characterized. The ASC extraction yield was 75%, 73% and 68%, respectively. The denaturation and melting temperatures of African catfish ASC (29.3°C and 100.0°C) were significantly higher than ASC of Salmon and Baltic cod (20.6°C and 90.5°C; 15.2°C and 86.7°C, respectively), assessed...
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Proces realizacji działań dotyczących miejskiego transportu ładunków
PublikacjaW artykule przedstawiono strukturę proces zarządzania realizacją działań dotyczących miejskiego transportu ładunków. Proces obejmuje etapy planowania, organizacji, realizacji i kontroli, przy czym szczególną uwagę poświęcono etapowi planowania. Jest to spowodowane zidentyfikowanymi na bazie doświadczeń zagranicznych problemami w praktycznej identyfikacji problemów związanych transportem ładunków poprzez podmioty odpowiedzialne...
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Organic Pollution in Surface Waters from the Fuglebekken Basin in Svalbard, Norwegian Arctic
PublikacjaThe Fuglebekken basin is situated in the southern part of the island of Spitsbergen (Norwegian Arctic), on the Hornsund fjord (Wedel Jarlsberg Land). Surface water was collected from 24 tributaries (B1-B24) and from the main stream water in the Fuglebekken basin (25) between 10 July 2009 and 30 July 2009. The present investigation reveals the results of the analysis of these samples for their PAH and PCB content. Twelve of 16 PAHs...
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|Analiza zmian funkcjonowania transportu zbiorowego wynikających z budowy węzłów integracyjnych
PublikacjaCoraz częstszym problemem zauważalnym podczas modernizacji lub przebudowy sieci transportowej miasta jest integrowanie środków transportu. Rozwiązaniem tej sytuacji jest budowa węzłów przesiadkowych umożliwiających lepszy dostęp do transportu publicznego. Niesie to za sobą skutki w postaci modyfikacji funkcjonowania linii transportu zbiorowego, co daje możliwość poszerzenia oferty przewozowej oraz efektywnego wykorzystania potencjału...
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TRANSPORT ZANIECZYSZCZEŃ, ZT; PG_00042395
Kursy OnlineProgram studiów obejmuje zajęcia z transportu zanieczyszczeń w wymiarze: 15 godzin wykładów, 15 godzin projektu/seminarium. Przedmiot może być zaliczony po osiągnięciu wszystkich efektów kształcenia przewidzianych przewodnikiem dydaktycznym (sylabusem). W trakcie semestru w obrębie przedmiotu student zapozna się z zagadnieniami związanymi z transportem, migracją zanieczyszczeń.
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Determination of flow properties of a serial connection of a directional control valve with (C=5.7, b=0.32) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> DCV -> ambient...
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Determination of flow properties of a serial connection of a directional control valve with (C=2.1, b=0.14) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> DCV -> ambient...
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Determination of flow properties of a serial connection of a pressure relief valve with (C=7.3, b=0.49) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a serial connection of a directional control valve with (C=2.8, b=0.25) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> DCV -> ambient...
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Determination of flow properties of a serial connection of a directional control valve with (C=5.5, b=0.37) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> DCV -> ambient...
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Determination of flow properties of a serial connection of a pressure relief valve with (C=6.4, b=0.45) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a serial connection of a pressure relief valve with (C=6.2, b=0.38) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a serial connection of a directional control valve with (C=2.4, b=0.26) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> DCV -> ambient...
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Determination of flow properties of a serial connection of a pressure relief valve with (C=3.3, b=0.40) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a serial connection of a directional control valve with (C=2.0, b=0.11) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> DCV -> ambient...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=6.40, b=0.45) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=3.30, b=0.40) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=7.30, b=0.49) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=5.50, b=0.37) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> DCV ->...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=2.40, b=0.26) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> DCV ->...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=2.80, b=0.25) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> DCV ->...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=2.00, b=0.11) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> DCV ->...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=2.10, b=0.14) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> DCV ->...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=6.20, b=0.38) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=5.70, b=0.32) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> DCV ->...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=5.30, b=0.38) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a parallel connection of two pneumatic elements with (C=4.40, b=0.42) and (C=6.00, b=0.25) from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of parallel connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in parallel. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a serial connection of a pressure relief valve with (C=4.4, b=0.42) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Determination of flow properties of a serial connection of a pressure relief valve with (C=5.3, b=0.38) and a air blow gun from changes in air pressure in a tank being emptied
Dane BadawczeThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a pressure relief valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> PRV -> ambient...
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Amphotericin B derivatives: novel strategy for the development of non-toxic, broad spectrum, fungicidal and overcoming multidrug resistance antifungal agents.
PublikacjaZaprezentowano porównawczą charakterystykę działania amfoterycyny B (AmB) oraz jej pochodnych o różnym stopniu selektywnej toksyczności na szczepy grzybów reperezentujących różne mechanizmy oporności. Były to mutanty C. albicans posiadające defekt w szlaku biosyntezy ergosterolu oraz wielolekooporne szczepy S. cerevisiae wyposażone w pompy eksportujące typu ABC i MFS. Badania obejmowały: 1)porównanie aktywności przeciwgrzybowej...
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Skutki zwarć łukowych w średnionapięciowych rozdzielnicach okrętowych z izolacją powietrzną
PublikacjaW artykule scharakteryzowano moc i napięcie łuku, jak również przedstawiono model termodynamiczny służący do obliczania ciśnienia i temperatury gazów w otoczeniu łuku zwarciowego. Przedstawiono przykładowy układ elektrowni okrętowej i zasilania najważniejszych odbiorników na statku do przewozu kontenerów, w tym 600 kontenerów chłodzonych. Na podstawie parametrów prądnic i silników, odbiorników zasilanych z rozdzielnicy głównej...
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The shape of an ROC curve in the evaluation of credit scoring models
PublikacjaThe AUC, i.e. the area under the receiver operating characteristic (ROC) curve, or its scaled version, the Gini coefficient, are the standard measures of the discriminatory power of credit scoring. Using binormal ROC curve models, we show how the shape of the curves affects the economic benefits of using scoring models with the same AUC. Based on the results, we propose that the shape parameter of the fitted ROC curve is reported...
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Sebastian Wilczewski dr inż.
OsobyDr inż. Sebastian Wilczewski jest zatrudniony na stanowisku adiunkta w Katedrze Zastosowań Informatyki w Zarządzaniu, Wydział Zarządzania i Ekonomii. Ponadto od ponad 20 lat pracuje w firmach informatycznych, gdzie zajmował stanowiska od inżyniera i konsultanta, poprzez stanowisko Project Managera, Portfolio Manager i Proces Ownera aż do stanowiska Team Leadera dla zespołu około 30 analityków IT. Zdobytą wiedzą i doświadczeniem...
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A novel dual-band rectifier circuit with enhanced bandwidth for RF energy harvesting applications
PublikacjaIn recent years, a rapid development of low-power sensor networks, enabling machine-to-machine communication in applications such as environmental monitoring, has been observed. Contemporary sensors are normally supplied by an external power source, typically in a form of a battery, which limits their lifespan and increases the maintenance costs. This problem can be addressed by harvesting and converting ambient RF energy into...
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Multi-transformer primary-side regulated flyback converter for supplying isolated IGBT and MOSFET drivers
PublikacjaThis paper presents primary-side voltage regulated multi-transformer quasi-resonant flyback converter (MTFC) for supplying isolated power switch drivers. The proposed topology offers distinct advantages over frequently used flyback converter possessing one high frequency transformer with isolated multiple outputs. Particularly, when a large number of separate dc supply units is required, then MTFC enables improved regular distribution...
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Induction Motor Multiscalar Model Based Sensorless Control Using Power Measurement
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