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Early Stages of RNA-Mediated Conversion of Human Prions
PublikacjaPrion diseases are characterized by the conversion of prion proteins from a PrPC fold into a disease-causing PrPSC form that is self-replicating. A possible agent to trigger this conversion is polyadenosine RNA, but both mechanism and pathways of the conversion are poorly understood. Using coarse-grained molecular dynamic simulations we study the time evolution of PrPC over 600 μs. We find that both the D178N mutation and interacting...
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Wykonanie prac związanych z oceną możliwości przejazdów pojazdów ponadnormatywnych przez most w ciągu drogi powiatowej Nowy Staw - Kącik
PublikacjaCelem ekspertyzy jest ocena możliwości przejazdów pojazdów ponadnormatywnych przez most w ciągu drogi powiatowej Nowy Staw - Kącik. Zakres opracowania obejmuje opis aktualnego stanu technicznego obiektu, prezentację analiz statyczno-wytrzymałościowych, wymiarowanie oraz orzeczenie dotyczące możliwości i warunków realizacji przejazdów.
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Numerical simulation of natural convection of Glycol-Al2O3 nanofluids from a horizontal cylinder
PublikacjaThis paper deals with natural convection around a circular cylinder with constant heat flux in a cavity using computational fluid dynamics. As fluids ethylene glycol and a mixture of ethylene glycol with Al2O3 nanoparticles (mass concentrations of nanoparticles: 0.1% and 1%) are chosen. Rayleigh number ranges from 3104 to 3105. The nanofluids are modeled with single-phase approach. For the investigated range of nanoparticle concentration, the...
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EXPERIMENTAL INVESTIGATION OF FREE CONVECTION OF GLYCOL-Al2O3 NANOFLUID FROM HORIZONTAL TUBE
PublikacjaNanofluids came to be seen as a new generation of coolants, both in single- and two phase systems. Furthermore, nanofluids or nanocomposites may be used as a media in a thermal energy storage (TES) in such systems as sensible heat storage (SHS) and phase change materials (PCM). In the SHS systems the dominating mechanism of the heat transfer is natural convection. However, in the literature only a few investigations of free convection...
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Free convection of water-Al2O3 nanofluid from horizontal porous coated tube
PublikacjaNanofluids are expected to enhance heat transfer in many thermal systems. Present efforts are concentrated on boiling heat transfer of nanofluids, although single phase convection is of key importance in various appliances such as car radiators or heating systems. This paper presents experimental results of heat transfer during free convection of water-Al3O3 nanofluid from horizontal tube covered with metallic porous coating. Contrary...
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Effect of the Geometrical Shape of a Partition on the Natural Convection of Two Fluids in a Separated Cavity
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Experimental investigation of forced convection of water/EGAl2O3 nanofluids inside horizontal tube
PublikacjaIn this paper, forced convection of water/EG-Al2O3 nanofluids inside horizontal stainless steel tube is studied experimentally. As base fluid served water/EG mixture of two ratios (60:50 and 50:50). Nanoparticle mass concentrations was 0.1% or and 1%. Transition and turbulent flow regimes were tested. Average heat transfer coefficient and pressure drop values were determined for nanofluids and compared to base fluids. Deterioration...
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Free convection of water-Al2O3 nanofluid from horizontal porous coated tube
PublikacjaThe main aim of the present study was to investigate the influence of nanoparticles on heat transfer coefficients during free convection of water-Al2O3 nanofluid from horizontal porous coated tube under atmospheric pressure for nanoparticle concentration of 0.01% by weight. Contrary to published data present study concerns on free convection of nanofluids in extensive, quiescent fluid.
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Numerical and experimental investigation of thermal convection near electric devices with vertical channels
PublikacjaThis paper presents the results of numerical and experimental investigation of thermal convection near heat emitting surfaces of an electric device. For the intensification of thermal convection, special vertical channels were formed near the heat emitting surfaces of the device. An experimental test has proved that there is an optimal length of the channels – thermal convection is the most intensive then. Air velocity vectors...
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Experimental investigation of forced convection of water-Al2O3 nanofluids inside horizontal tubes,
PublikacjaIn this paper, forced convection of water–Al2O3 nanofluids inside horizontal copper tube is studied experimentally. Experiments were conducted for three, i.e. 0.1%, 1% and 5% nanoparticle mass concentrations under transition and turbulent flow regimes. Average heat transfer coefficients and pressure drop values were determined and compared to distilled water. Enhancement of heat transfer for lower nanoparticle concentration and...
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Experimental investigation of free convection of glycol-Al2O3 nanofluid from horizontal tube
PublikacjaNanofluids came to be seen as a new generation of coolants, both in single- and two phase systems. Furthermore, nanofluids or nanocomposites may be used as a media in a thermal energy storage (TES) in such systems as sensible heat storage (SHS) and phase change materials (PCM). In the SHS systems the dominating mechanism of the heat transfer is natural convection. However, in the literature only a few investigations of free convection...
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Experimental Investigation of Free Convection Heat Transfer from Horizontal Cylinder to Nanofluids
PublikacjaThe results of free convection heat transfer investigation from a horizontal, uniformly heated tube immersed in a nanofluid are presented. Experiments were performed with five base fluids, i.e., ethylene glycol (EG), distilled water (W) and the mixtures of EG and water with the ratios of 60/40, 50/50, 40/60 by volume, so the Rayleigh (Ra) number range was 3 104 Ra 1.3 106 and the Prandtl (Pr) number varied from 4.4 to 176....
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Experimental Investigations of Forced Convection of Nanofluids in Smooth, Horizontal, Round Tubes: A Review
PublikacjaA comprehensive review of published works dealing with experimental studies of forced convection heat transfer of nanofluids is presented. The survey is limited to straight, smooth, and round tubes. Moreover, only mono nanofluids exhibiting Newtonian behaviour are considered. Works on experimental research of forced convection in tubes are presented in a chronological order in the first part of the article. In this part, attention...
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Sample Rate Conversion Based on Frequency Response Masking Filter
PublikacjaThe sample rate conversion with high resampling ratios requires low-pass digital filters with very narrow transition band which results in high computational complexity and makes filter design problematic. Therefore in this work we propose to use the FRM method, which breaks the filter with a narrow transition band into a group of filters with reduced design requirements. These decreases the number of non-zero coefficients and...
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On Sample Rate Conversion Based on Variable Fractional Delay Filters
PublikacjaThe sample rate conversion algorithm based on variable fractional delay filters is often used if the resampling ratio cannot be expressed as the ratio of small integer numbers or if it is not constant. The main advantage of such solution is that it allows for arbitrary resampling ratios which can even be changed during the resampling process. In this paper a discussion on influence of different approaches to fractional filter...
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Clinical and conventional pharmacy services in Polish hospitals: a national survey
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Comparative study of flow condensation in conventional and small diameter tubes
PublikacjaFlow boiling and flow condensation are often regarded as two opposite or symetrical phenomena. Their description however with a single correlation has yet to be suggested.In the case of flow boiling in minichannels there is mostly encountered the annular flow structure, where the buble generetion is not present. Similar picture holds for the case of inside tube condensation, where annular flow structure predominates. In such case...
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A Point Set Connection Problem for Autonomous Mobile Robots in a Grid
PublikacjaConsider an orthogonal grid of streets and avenues in a Manhattan-like city populated by stationary sensor modules at some intersections and mobile robots that can serve as relays of information that the modules exchange, where both module-module and module-robot communication is limited to a straight line of sight within the grid. The robots are oblivious and move asynchronously. We present a distributed algorithm that, given...
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A closed loop thermosyphon with conventional or minichannel based condenser and evaporator
PublikacjaPrzedstawiono uogólniony model termosyfonu, który może być rozpatrywany dla szeregu wariantów.Model opiera się na jednowymiarowych równanich masy, pędu i energii. Rozpatrzono dwa przypadki termosyfonu, tj. grzanie strony pionowej i chłodzenie strony pionowej oraz drugi, gdzie termosyfon jest ogrzewany na stronie pionowej a chłodzony na poziomej.
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Conventional and unconventional yeasts able to grow on rapeseed meal hydrolysates
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The Connection Betweenagrand SCCmecElements ofStaphylococcus aureusStrains and Their Response to Photodynamic Inactivation
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Growth and characterization of chalcopyrite nanocrystals: beyond conventional thin films
PublikacjaPrzedstawiona została sucha metoda wytwarzania na podłożach stałych kryształów chalkopirytu zawierających miedź z wykorzystaniem prekursorów metalicznych. Dzięki odpowiedniemu doborowi parametrów nakładania otrzymano zarówno nanokryształy oraz polikrystaliczne struktury submikronowe jak i makroskopowe klastry. Zamieszczona została charakterystyka wytworzonych materiałów otrzymana techniką mikroskopii skaningowej.
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Application of guided waves in the evaluation of steel-concrete adhesive connection
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Polarization Conversion of Solitons Propagating in Birefringent Microstructured Optical Fibers
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Performance of FAN conception of traffic control in IP QoS networks
PublikacjaIn this paper we present the architectural implementation of Flow Aware Networking (FAN), a new approach for realizing QoS guarantees in the Internet. We also propose FAN traffic control algorithm which performs traffic control on flow level. Using the proposed FAN node model, we conduct simulation research to prove if FAN can be a new approach for realizing QoS guarantees. The basis of this research is finding a way to guarantee...
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Fixed roof to shell connection in tank with an internal floating cover.
PublikacjaReferat dotyczy projektowania połączenia dachu stałego zbiornika walcowego z płaszczem w przypadku zastosowania wewnętrznego przekrycia pływającego. Zaproponowano zastosowanie dodatkowego pierścienia usztywniającego, zabezpieczającego górną krawędź płaszcza zbiornika. Wyniki analiz z zastosowaniem metody elementów skończonych zamieszczono w formie map naprężeń.
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Annual variations in the solar energy conversion efficiency in will coppice stand.
PublikacjaMonitorowano produkcyjność plantacji wiklinowych w Uppsali w Szwecji w latach 1985-1994. Okazało się, że największa sprawność przetwarzania energii słonecznej w biomasę ma miejsce w drugim i trzecim roku uprawy wiklinowej (około 1%), natomiast w pierwszym i w czwartym roku sprawność ta jest 2 razy niższa i wynosi około 0,5%. Dyskutuje się przyczyny takiej sytuacji.
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Conception of taking decisions with regard to reliability and safety of combustion engines
PublikacjaW referacie przedstawiono jedną z najprostszych sytuacji decyzyjnych, która może pojawić sie w czasie eksploatacji silników spalinowych. Zaproponowano możliwość podejmowania decyzji w takiej sytuacji. Wynika z niej, że nawet w złożonej sytuacji decyzyjnej rozpatrywanie oczekiwanych konsekwencji umożliwia bardzo łatwe przyporządkowanie każdemu rodzajowi decyzji, pojedynczej liczby oznaczającej wartość oczekiwaną konsekwencji. Umożliwia...
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On bounded load routings for modeling k-regular connection topologies
PublikacjaW pracy analizowane są problemy modelowania k-regularnych topologii sieci komputerowych z punktu widzenia routingu typu point-to-point. Zaprezentowane są algorytmy oraz przeprowadzona jest analiza złożoności obliczeniowej.
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The influence of brace to chord rotational connection stiffness on stability of the truss
PublikacjaThe paper is devoted to the numerical analysis of the roof truss subjected to upward wind loading and braced at the tensioned top chord. The linear buckling analysis were performed for the beam and shell model of the structure. As the result the influence of rotational connection stiffness between the brace and the top chord on the truss stability was appointed. The biaxial strength testing machine was used to conduct the experimental...
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Rotational stiffness of a connection made using a single prestressed bolt
PublikacjaThe often overlooked rotational stiffness of connections utilizing a single prestressed bolt leads to the common assumption of treating such connections as pinned or even modeling them as rigid. Nevertheless, considering the friction between interconnected elements, it is evident that the actual rotational stiffness lies between these simplified assumptions. This study is dedicated to quantifying this stiffness and addressing the...
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ASON/GMPLS connection control servers in virtual computer environment
PublikacjaIn the paper ASON/GMPLS connection control servers layer in the context of Next Generation Network (NGN) is described. The implementation of ASON/GMPLS connection control servers in virtual computer environment as well as performed measurements are presented. Some aspects of virtual environment installation are depicted. Remarks regarding application of the virtual computer environment to realization of communication between NGN...
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Conception for diagnosing SI engines fed with biofuel in operation conditions
PublikacjaThe article deals with the question of diagnosing the high power self ignition (SI) engines fed with pro-ecologic fuels in an aspect of appearing operation problems. There has been presented the specific of action and techno-operation profile of the combustion engine foreseen as an investigations object. The preliminary conception of diagnostic investigations of the engine 7L35MC type produced in H. Cegielski - Poznan S.A. factory...
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Comparative study of flow condensation in conventional and small diameter tubes
PublikacjaFlow boiling and flow condensation are often regarded as two opposite or symmetrical phenomena, however their description with a single correlation has yet to be suggested. In the case of flow boiling in minichannels there is mostly encountered the annular flow structure, where the bubble generation is not present. Similar picture holds for the case of inside tube condensation, where annular flow structure predominates. In such...
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Comparative study of flow condensation in conventional and small diameter tubes
PublikacjaIn the paper a method developed earlier by the first author is applied to calculations of heat transfer coefficient for inside tube condensation. The method has been verified using experimental data from literature on several fluids in different microchannels and compared to three well established correlations.
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Conception of interactive information and decision support system - model and evaluation
PublikacjaThis article presents conception of interactive information and decision support system for urban and industrial air quality management. The emphasis of the project is on real-time analysis and multi-media information, and support of distributed and mobile clients through the Internet.
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The categorization of the tourist services quality perception determinants in hierarchical conception
PublikacjaW niniejszym rozdziale zaprezentowano kategoryzację determinant percepcji jakości usług turystycznych. Omówione zostały główne grupy oraz determinanty elementarne z wykorzystaniem ujęcia modeli hierarchicznych.
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Offshore project management based on jack-up rig conversion
PublikacjaChapter presents aspects of Offshore project management during conversion drilling rig to accommodation rig in Batam Indonesia
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Application of guided waves in the evaluation of steel-concrete adhesive connection
PublikacjaThe aim of the paper is the application of guided waves in the evaluation of a condition state of adhesive connection between steel and concrete. The study concerns a push-out specimen consisting of two steel plates glued to opposite faces of a concrete cube with the use of structural adhesive. Wave propagation in the specimen without external load is investigated both experimentally and numerically. The second stage of the investigation...
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Modified Manganese Phosphate Conversion Coating on Low-Carbon Steel
PublikacjaConversion coatings are one of the primary types of galvanic coatings used to protect steel structures against corrosion. They are created through chemical reactions between the metal surface and the environment of the phosphating. This paper investigates the impact that the addition of new metal cations to the phosphating reaction environment has on the quality of the final coating. So far, standard phosphate coatings have contained...
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Synthesis and Characterization of Poly(zwitterionic) Structures for Energy Conversion and Storage
PublikacjaZwitterions are unique class of molecules that possess two functional groups bearing electric charges, one positive and second negative. This setup results in peculiar properties such as high water retention and anti-fouling capability. Therefore, zwitterionic coatings and gels are commonly applied in e.g. biosensing and bioelectronic devices. Despite those applications, there are other perspectives for zwitterionic materials....
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CFD analysis of natural convection between two superposed fluids: role of corrugated bottoms
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Intensification of thermal convection near electric devices using flat screens – computer modelling
PublikacjaIntensification of natural thermal convection near electric devices is possible by application of additional elements as screens creating convection canals close to the device. In the earlier authors paper the results of the analysis of thermal convection with the use of only one additional screen close to the electric device were presented. This paper presents computer modelling of thermal convection when two screens near the...
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Fermentative Conversion of Two-Step Pre-Treated Lignocellulosic Biomass to Hydrogen
PublikacjaFermentative hydrogen production via dark fermentation with the application of lignocellulosic biomass requires a multistep pre-treatment procedure, due to the complexed structure of the raw material. Hence, the comparison of the hydrogen productivity potential of different lignocellulosic materials (LCMs) in relation to the lignocellulosic biomass composition is often considered as an interesting field of research. In this study,...
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Enhanced energy conversion as a result of fluid-solid interaction in micro- and nanoscale
PublikacjaIt is known that nano- and micromechanics require new approaches to right describing of surface-like phenomena which lead to an enhanced energy conversion. In this work, a general form of surface forces that consist of a contribution from both the friction and mobility components has been extended to collect the effects of bulk and surface motion of a fluid. Quite similar impact can be observed for a solid-fluid mixture, where...
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VSC converters control for offshore wind farms HVDC grid connection
PublikacjaThe paper proposes a voltage sourced converter (VSC) new control method. A well-known in the electric power systems correlation between voltage angle and active power and correlation between voltage and reactive power is used instead of feedforward control. This allows for a fast and almost independent control of active and reactive power flow.
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Energy conversion in small water plants with variable speed PM generator
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Selected nutrients determining the quality of different cuts of organic and conventional pork
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Stress analysis in the steel tank shell at its connection with product pipeline
PublikacjaPrzeanalizowano zaburzenia stanu błonowego w powłoce zbiornika walcowego pionowego w strefie przyłączenia do płaszcza rurociągu produktowego
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Prefabricated structures under earthquake excitation: damage and failure of connection joints
PublikacjaCelem artykułu jest analiza zachowania się złączy pomiędzy elementami belkowymi a słupami w konstrukcjach prefabrykowanych poddanych obciążeniom dynamicznym powstającym podczas trzęsień ziemi. Wyniki przedstawione w pracy, uzyskane na podstawie badań numerycznych przeprowadzonych dla wybranego modelu konstrukcji, pokazują, iż złącza są najsłabszym elementem wymagającym zwrócenia szczególnej uwagi przy projektowaniu konstrukcji...