2015 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2015

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INFLUENCE OF NANOPARTICLE CONCENTRATION ON THERMAL PROPERTIES OF THERMAL OIL-MWCNT NANOFLUID
- Janusz Cieśliński
- Katarzyna Ronewicz
2015
This paper deals with measurements of dynamic viscosity, thermal conductivity, electrical conductivity and pH of thermal oil-MWCNT (TO-MWCNT) nanofluid. Nanoparticles were tested at the concentration of 0.001%, 0.005%, 0.01%, 0.05%, and 0,1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. Thermal oil (TO) was selected as a base liquid, because of possible application in ORC systems as an intermediate heating agent [20]. The results obtained for tested nanofluids were compared with predictions made by use of existing models for liquid/solid particles mixtures.
Influence of pitting corrosion on fatigue and corrosion fatigue of ship and offshore structures. Part II: Load - pit crack interaction
- Marek Jakubowski
2015 Pełny tekst Polish Maritime Research
In the paper has been discussed influence of stresses on general corrosion rate and corrosion pit nucleation and growth rate, whose presence has been questioned by some authors but accepted by most of them. Influence of pit walls roughness on fatigue life of a plate suffering pit corrosion and presence of so called "non damaging" pits which never lead to initiation of fatigue crack, has been presented. Possibility of prediction of pit-to-crack transition moment by two different ways, i.e. considering pit as a stress concentrator or as an equivalent crack, has been analyzed. Also, influence of statisyical distribution of corrosion pits depth as well as anticorrosion protection on fatigue and corrosion fatigue of pitted elements, have been described.
INFLUENCE OF PRESERVATIVE ON THE TENSILE STRENGTH OF THE TISSUE OF PORCINE CIRCULATORY SYSTEM
- Kinga Dawidowska
- Alicja Stanisławska
2015 Pełny tekst Advances in Materials Science
Currently one of the leading causes of death worldwide is heart diseases which include calcification of heart valves and vascular aneurysm. There are many biomaterials that can substitute pathologically altered tissue, however, none of them is as perfect as native tissue. Currently, scientists are looking for new biomaterials that can be successfully implanted without exposing the patient to reoperation. Each material introduced into an organism must afford sufficient mechanical and biochemical properties and meet the criteria of the biomaterial. The most important mechanical properties include fatigue strength, longitudinal and transverse tensile strength and elastic modulus otherwise known as Young's modulus. Materials intended to take over the function of natural tissue materials should be characterized to the greatest extent by similar mechanical properties to them. Therefore this study provides an overview of selected methods for the tensile tests characterizing the mechanical properties of the heart valves, pericardium and porcine aortas. We also present results of our study of mechanical properties of natural porcine tissues.
Influence of reduction process on the structural and mechanical properties of (Pb,Bi)-(Si,Ge)-O oxide glasses
- Beata Bochentyn
2015 Pełny tekst Technical Issues
The effect of the reduction process in H2 at 380 °C on the microstructure and elemental composition of a glass Bi0.4Pb0.2Si0.4Ox has been investigated. It has been shown that after reduction a clearly separated top layer with a thickness of approx. 50 µm was formed on the surface of the sample. This layer is depleted of oxygen and has higher electrical conductivity than the interior of the glass. It has also been found that some granules of metallic bismuth with a diameter of tens to hundreds of nanometers were formed on the surface of the glass. Furthermore, depletion of lead was observed in these samples in relation to the initial stoichiometry of the glass prior to trial reduction.
Influence of Road Wetness on Tire-Pavement Rolling Resistance
- Jerzy Ejsmont
- Leif Sjogren
- Beata Świeczko-Żurek
- Grzegorz Ronowski
2015 Pełny tekst Journal of Civil Engineering and Architecture
Rolling resistance of tires is one of the most important factors influencing energy consumption of road vehicles, especially on rural roads. For practical reasons, most of rolling resistance measurements are usually performed for dry road conditions. Based on the fact that roads are wet during a considerable time over the year and as part of the projects MIRIAM, ROLRES and ROSANNE, the TUG (Technical University of Gdańsk) in Poland and VTI (Swedish National Road and Transport Research Institute) in Sweden carried out trailer rolling resistance measurements on wet road surfaces to investigate water film influence on rolling resistance on different pavements. A specially-designed trailer to measure rolling resistance has been used. The test sections were both rural roads and an abandoned airfield equipped with water film sensors mounted in the pavement. Results indicate strong influence of test speed and water film depth, as well as influence of surface texture. The increase of rolling resistance on wet surfaces is caused by both hydrodynamic phenomena and cooling effect of water that decreases tire temperature thus increasing rolling resistance.
Influence of sensor design and optical properties of tissue on the photoplethysmographic signal
- Agnieszka Gorczewska
2015
Photopletysmography and an associated technique called pulse oximetry are still explored due to the expectations that they give a lot of information about the state of the patient and, also, due to the fact that they are non invasive. Knowledge about the impact of various parameters on the measured signal leads to a faster and a more reliable way of analyzing measurement results and finding the dependencies between the involved factors. This study is an overview, where different factors which have an impact on measuring the PPG signal are presented. The factors related to the sensor structures, namely: wavelength, distance between the light source and the detector, mode of work: transmissive or reflective, are presented together with the light interactions with tissue described by absorption and scattering coefficients, the refractive index and the anisotropy factor.
Influence of separation gap on the structural response of colliding structures under earthquake excitation
- Barbara Sołtysik
- Robert Jankowski
2015
The high level of urbanization in the XXIst century forces the designers to design closely-separated structures and to take into account many factors influencing their response during seismic excitation, which are the most unpredictable loads which can affect civil engineering structures. Interactions between insufficiently adjacent buildings, known as the earthquake-induced structural pounding, may cause serious damage to the structures, leading even to its total collapse. The main reason of collisions between adjacent buildings during earthquakes, aside from insufficient distances between structures is related to the difference in dynamic parameters. The aim of this paper is to present the results of an experimental study of collisions due to insufficient separation gap between models of steel structures under earthquake excitation. To perform this study, models of three steel towers, with different dynamic parameters were constructed. To obtain the seismic excitation, the unidirectional shaking table, located at the Gdansk University of Technology (Poland), was used. To obtain different dynamic characteristics of structures, additional mass – concrete plates with the dimensions of 50x50x7 cm and 42.2 kg weight – were mounted at the top of each tower. In the experiment, two configurations of the towers were analyzed. The paper shows the results obtained for the configuration, in which two concrete plates were mounted at the top of external towers and only one concrete plate was mounted at the top of the middle tower. The influence of different separation gap (=0 mm, =20 mm, =40 mm, =60 mm) was taken into consideration. The results clearly indicate that insufficient in-between separation distance may result in interactions between buildings with different dynamic properties during earthquakes, leading to the change of their responses. The best behavior of structures has been observed for the case of zero gap size as well as when the gap size is large enough to prevent pounding.
Influence of Shunt Compensation with SVC Devices on Resonance Risk in Power Systems
- Robert Kowalak
- Robert Małkowski
- Stanisław Czapp
- Jacek Klucznik
- Zbigniew Lubośny
- Krzysztof Dobrzyński
2015
Many analyses are required to locate a new reactive power source in a power system. The choice of a location is a very complex matter which requires various aspects to be considered. Selecting a location also entails the necessity to assess it from the point of view of the selected compensator’s structure as well as the system’s performance in various states with the new device on. The paper presents the issues of assessing compensator location from the point of view of resonance phenomena. It indicates the factors which affect a circuit’s resonance conditions, including a change in network configuration and compensator’s structure.
Influence of Spatial Structures of 316L Stainless Steel on Its Cavitation Erosion Resistance
- Beata Śniegocka
- Marek Szkodo
- Jarosław Chmiel
2015 Solid State Phenomena
Cavitation erosion performance of modified macroscopic internal structure 316L stainless steel was investigated. The samples processed by means of SLM method were subjected to cavitation erosion test. The scanning electron microscope Philips 30/ESEM was used to examine morphology of eroded surface.
Influence of Staphylloccoccus bacteria adhesion on the degradation of the Ti6Al4V alloy
- Michał Bartmański
- Beata Świeczko-Żurek
- Andrzej Zieliński
2015 SYLWAN
The paper deals with bacteria adhesion and the degradation of the Ti6Al4V alloy
INFLUENCE OF TEMPERATURE ON THE ACTIVITY OF ANAMMOX GRANULAR BIOMASS - SHORT AND LONG-TERM ASPECT
- Dominika Sobotka
- Krzysztof Czerwionka
- Jacek Mąkinia
2015
The aim of this study was to determine a short-term and long-term effect of temperature on the anammox process rate and determination of temperature coefficients in the Arrhenius and Ratkowski equations. The short-term effects of temperature on the anammox biomass were investigated in batch tests at ten different temperatures in the range of 10-55 ̊C. The maximum rate 1.3 gN (gVSS·d)-1 observed at 40 ̊C. The minimum rate, close to 0 gN (gVSS·d)-1, was observed for the limit values of the analyzed temperature range, (10 and 55 ̊C). The activity tests done at 55 ̊C showed an irreversible loss of the activity due to the biomass lysis. Subsequently, a lab-scale SBR was operated at different temperatures (from 30 to 11 ̊C) to determine the long-term effects. The system was still successfully operated at 15 ̊C but when the temperature was decreased to 11 ̊C, nitrite started to accumulate and the system lost its stability.
INFLUENCE OF TEST CONDITIONS ON TYRE/ROAD NOISE MEASURED BY THE DRUM METHOD
- Jerzy Ejsmont
- Stanisław Taryma
- Beata Świeczko-Żurek
2015
Tyre/road noise is one of the most important environmental problems related to road traffic. Nowadays a few standard procedures of tyre/road noise measurements are in use. Unfortunately, measurement conditions specified within relevant standards are very different. For example, procedure described in ISO 11819-2 used for pavement investigations requires tyre load of 3200 N and capped inflation pressure of 200 kPa. At the same time ECE Regulation No. 117 requires tyre load based on the Load Index of the tyre and inflation pressure calculated according to a certain equation. In many studies it is speculated that such difference in load and inflation may result in serious differences of tyre ranking. Technical University of Gdansk performed drum measurements of tyre/road noise in order to clarify the situation. The drum method was selected as in comparison to the coast-by and trailer methods, it gives more freedom in adjusting load and inflation pressure. The measurements were performed on drum facilities covered with replica road surfaces including, among others, the replica of ISO 10844 reference surface. Test tyres included reference tyres specified in ISO 11819-2 and a few market tyres that are in use nowadays. Also a tyre specially designed for Electric Vehicles was tested. The paper presents both A-weighted overall noise levels and third octave band spectra.
Influences of grain shape and size distribution on permeability
- Nurullah Akbulut
- Mateusz Wiszniewski
- Ali Firat Cabalar
2015
The present study investigates the effects of shape and size distributions of grains on the coefficient of permeability (k). A series of constant head permeability tests were performed to characterize the coefficient of permeability. Three particle size ranges (4.75- 0.075, 1.18- 0.075 and 0.300-0.075 mm) of two different sands (Narli Sand, Crushed Stone Sand) having different shapes were tested in a constant head permeability testing apparatus at a relative density (Rd) of about 35% and, a constant room temperature (20oC). Some physical properties of the sands employed, such as median particle diameter (D50), effective particle diameter (D10) coefficient of uniformity (cu), and coefficient of curvature (cc), were the same for these two sands. Experimental results showed that the coefficient of permeability values of Crushed Stone Sand (CSS) was higher than those of Narli Sand (NS). Empirical equations derived by numerous researchers for the coefficient of permeability prediction have been implemented on the estimated permeability values obtained from the laboratory.
Information Logistics as a Paradigm
- Anna Bobkowska
2015 Pełny tekst Annals of Computer Science and Information Systems
This paper presents a paradigm-based approach to information logistics. The approach deals with extracting concepts specific to information logistics in categories typical to paradigms. The resulting description should be easily connected to complementary components which are based on other paradigms, e.g. business process management and information systems development. Empirical part aims at checking and enhancing features typical to information logistics. It is conducted with action research of applying information logistics paradigm in coordination of Erasmus+ program.
Information Retrieval in Wikipedia with Conceptual Directions
- Julian Szymański
2015
The paper describes our algorithm used for retrieval of textual information from Wikipedia. The experiments show that the algorithm allows to improve typical evaluation measures of retrieval quality. The improvement of the retrieval results was achieved by two phase usage approach. In first the algorithm extends the set of content that has been indexed by the specified keywords and thus increases the Recall value. Then, using the interaction with the user by presenting him so-called Conceptual Directions the search results are purified, which allows to increase Precision value. The preliminary evaluation on multi-sense test phrases indicates, that the algorithm is able to increase the Precision, within result set, without Recall loss. We also describe an additional method used for extending the result set based on creating cluster prototypes and finding the most similar, not retrieved content in text repository. In our demo implementation in the form of web portal, clustering has been used to present the search results organized in thematic groups instead of ranked list.
Information System for Drivers Within the Integrated Traffic Management System - TRISTAR
- Jacek Oskarbski
- Marcin Zawisza
- Michał Miszewski
2015
Advanced traveler information systems (ATIS) for drivers are a very important element of modern traffic management. In recent years ITS infrastructure is being developed also in Poland. It allows for delivering to drivers information related to the conditions in the road network through, inter alia, dedicated Variable Message Signs (VMS). Such information enables drivers to take decisions, contributing to improving the efficiency and safety of the transport system. They also allow to manage the traffic speed dynamically, taking into account weather conditions hazards, temporary disruptions or incidents. Paper provides an overview of different solutions for Advanced Traveler Information Systems in Poland. The place of ATIS in architecture of Tri-City TRISTAR system is described as well as the use of data, functions and algorithms that allow them to be implemented. Furthermore ATIS development plans and plans for research to be carried out to improve the functioning of the system are presented.
Infrastruktura dla Pomorskich Tras Rowerowych R-10 i R-9 o znaczeniu międzynarodowym. Opis założeń projektowych
- Ksenia Piątkowska
2015
Projekt koncepcji zagospodarowania rowerowych miejsc postojowych powstał w ramach przedsięwzięcia strategicznego "Pomorskie Trasy Rowerowe o znaczeniu międzynarodowym R-10 i Wiślana Trasa Rowerowa (R-9)", którego inicjatorem i koordynatorem był Departament Turystyki i Promocji Urzędu Marszałkowskiego Województwa Pomorskiego. Założeniem przedsięwzięcia było wybudowanie dwóch oznakowanych tras rowerowych z dedykowana infrastrukturą (m.in. tablice informacyjne, miejsca odpoczynku dla rowerzystów) o międzynarodowych standardach, dających możliwość certyfikacji szlaków jako Euro-Velo. Obszar objęty planowana inwestycją w przeważającej części jest terenem wiejskim, w znacznej części o charakterze rolniczym lub leśnym. Pierwszym etapem prac projektowych nad zdefiniowaniem fizycznego wyglądu komponentów infrastruktury przewidzianej przedsięwzięciem było stworzenie "Katalogu rozwiązań modułowej infrastruktury turystycznej rowerowych szlaków turystycznych", będącego zbiorem elementów małej architektury, rekomendowanych do zastosowania przy wykonywaniu rowerowych miejsc odpoczynku w poszczególnych gminach. Obiekty powstałe w wyniku prac nad Katalogiem są oryginalnymi formami autorstwa zespołu sformowanego przez specjalistów z zakresu Design Thinking, architektury, wzornictwa przemysłowego, grafiki i IT.
Infrastruktura logistyczna w morskich portach jachtowych
- Marcin Forkiewicz
2015 Logistyka
Niezbędnym czynnikiem, warunkującym realizację funkcji logistycznych morskich portów jachtowych w obsłudze jednostek pływających oraz żeglarzy jest odpowiednia infrastruktura techniczna. Ponadto procesy logistyczne w porcie są uwarunkowane relacją jacht żaglowy lub motorowy – port lub przystań jachtowa. Z drugiej strony, wykorzystanie infrastruktury w realizacji procesów logistycznych, w istotny sposób wpływa nie tylko na sprawność i niezawodność, ale także na efektywność świadczonych usług dla jachtów i żeglarzy – armatorów i przypływających gości. W artykule przeanalizowano logistyczną infrastrukturę morskich portów jachtowych, bazując na doświadczeniach krajowych i międzynarodowych.
Infrastruktura PL-LAB2020
- Artur Binczewski
- Bartosz Belter
- Łukasz Łopatowski
- Michał Giertych
- Wojciech Burakowski
- Halina Tarasiuk
- Andrzej Bęben
- Maciej Sosnowski
- Piotr Krawiec
- Janusz Granat
- Piotr Wiśniewski
- Wojciech Szymak
- Adam Grzech
- Paweł Świątek
- Patryk Schauer
- Radosław Adamkiewicz
- Józef Woźniak
- Krzysztof Gierłowski
- Wojciech Gumiński
- Krzysztof Nowicki
- Andrzej Chydzyński
- Błażej Adamczyk
- Dominik Samociuk
- Agnieszka Brachman
2015 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne
Przedstawiono infrastrukturę sieci badawczej PL-LAB2020. Zaprezentowano 7 laboratoriów badawczych PL-LAB umożliwiających prowadzenie badań w głównych ich obszarach zdefiniowanych dla programu Horyzont 2020. Przedstawiono szczegóły struktury operacyjnej PL-LAB2020 łączącej zasoby poszczególnych laboratoriów zlokalizowane w 6 ośrodkach naukowo-badawczych w jedno rozproszone środowisko badawcze. Ostatecznie pokazano, jak infrastruktura PL-LAB2020 została połączona z innymi sieciami badawczymi w Europie.
Inhibition of the granular anammox process by the high concentration of free ammonia.
- Dominika Sobotka
- Krzysztof Czerwionka
- Jacek Mąkinia
2015
High concentrations of ammonia and nitrite, typical for reject water treatment in the anammox process with the use of high temperatures and pH, may cause free ammonia (FA) inhibition. In this study, the inhibitory effect of FA on anammox process rate was investigated in a bench-scale sequencing batch reactor (SBR) with granular anammox biomass. Results of the study present that the anammox process could be successfully operated at an FA concentration below 4 mgN•L-1. The anammox process rate decreased almost immediately when FA concentration increased up to 10.6 mgN•L-1. Short-term high concentrations of FA had no effect on the qualitative and quantitative composition of the anammox bacteria population.