2014 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2014

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Reduction of Tire Rolling Resistance by Optimization of Road Surfaces and Tires
- Beata Świeczko-Żurek
- Jerzy Ejsmont
- Grzegorz Ronowski
2014
During interaction between tire and road surface three very important phenomena are always in effect. One of them (very desirable) is friction that is important for traction, braking and cornering. Two other phenomena are not desirable at all, that is rolling resistance and noise. This paper discusses relations between road surface and tire parameters versus tire rolling resistance. Road surface texture, porosity, impedance, strength and wearing resistance must be optimized for the best performance in certain condition. Different requirements apply to tires and road surfaces intended for high speed roads and different characteristics are desirable for road surfaces and tires designed for low speed urban areas, especially where the traffic is composed with many low emission vehicles (LEV). The authors work on optimization of tires and road surfaces for LEV’s (hybrid and electric cars) within the Polish-Norwegian project LEO.
Reduction of vibrations of steel structure models with Polymeric Bearings - experimental study
- Tomasz Falborski
- Robert Jankowski
2014
Earthquake-induced ground motions are the most severe and unpredictable threats to the structures all around the world. Therefore, designing earthquake protective systems has become an extremely challenging problem in civil engineering. Base isolation is one of the most popular and widely adopted methods of protecting structures against earthquake forces. The present paper reports the results obtained from the shaking table experimental study, which was aimed to verify the effectiveness of the Polymeric Bearings (PB), as a proposal of a new base isolation system, in suppressing structural vibrations under strong ground motions. The dynamic behaviour of two steel structure models, both fixed-base and base-isolated, subjected to the El Centro earthquake, was studied. The reduction in lateral response was measured by comparing the peak accelerations recorded at the top floor of the analyzed models, with and without PBs. The results of the study indicate that installation of the PBs leads to significant improvement in dynamic response by suppressing structural vibrations under earthquake excitation.
Redukcja obciążeń odmorskich ścian falochronów pionowościennych przy zastosowaniu ścian ażurowych i komór wygaszających
- Aleksandra Wawrzyńska
- Waldemar Magda
2014 Pełny tekst Scientific Journal of Gdynia Maritime University
Poszukiwanie optymalnych rozwiązań w projektowaniu falochronów portowo-morskich stanowi ciągłe wyzwanie dla projektantów w dziedzinie hydrotechniki portowo-morskiej. W przypadku falochronów morskich jednym z decydujących czynników mających wpływ na wybór rodzaju konstrukcji jest uzyskanie maksymalnej możliwej redukcji obciążeń od falowania morskiego. Niniejsza praca poświęcona jest rozwiązaniom konstrukcyjnym skrzyń żelbetowych, w których zastosowano pionową ścianę ażurową oraz otwartą komorę wygaszającą. Sprawdzono wpływ zastosowania nowych rozwiązań konstrukcyjnych na redukcję obciążeń pionowych ścian falochronów morskich.
Reforms of Polish Antitrust Law: Closer to, or Further From, the European Model? Journal of European Competition Law and Practice
- Krystyna Kowalik-Bańczyk
2014 Journal of European Competition Law & Practice
The Polish Act on the Protection of Competition and Consumers has been recently amended. Changes include the introduction of a two-phase based merger control, a more efficient leniency program, and the administrative liability of individuals involved in antitrust agreements.
Regionalna strategia w obszarze polityki rynku pracy w województwie pomorskim
- Piotr Dominiak
- Małgorzata Gawrycka
2014 Polityka Społeczna
Celem artykułu jest przedstawienie strategii i planów działań w obszarze rynku pracy przygotowanych przez władze samorządowe województwa pomorskiego.. Władze regionalne i lokalne województwa pomorskiego opracowały szereg dokumentów wytyczających główne kierunki polityki rynku pracy. Najważniejsze z nich to „Strategia rozwoju województwa pomorskiego do roku 2020” oraz „Regionalny Plan Działań na Rzecz Zatrudnienia dla województwa pomorskiego”. Ich pozytywną cechą jest spójność wzajemna oraz z odpowiednimi dokumentami i planami centralnymi. Punktem wyjścia dla opracowania tych dokumentów i wynikającej z niej strategii w zakresie rynku pracy są dysproporcje rozwojowe występujące w województwie pomorskim. Rzutują one bardzo silnie na sytuację na lokalnych rynkach pracy, co wymaga zróżnicowanego podejścia m.in. do działań zmierzających do ograniczenia bezrobocia i zapobiegania marginalizacji niektórych grup społecznych.
REINFORCED CONCRETE SUPPORTING CONSTRUCTION OF THE STADIUM COVER FOR EURO 2012 IN GDAŃSK
- Ryszard Wojdak
2014
In the article structural issues that connected with the reinforced concrete supporting construction of the stadium roofing for EURO 2012 in Gdańsk were described. In the first part of the article the concept of stadium foundation were described. In the second the static - strength analysis for two variants fastening together individual foundation elements were made. The two assumed geometrically different concept of foundation were subjected to: dead load of the construction and service load, in which wind pressure coming from the structure of steel roofing was included. For individual schemes results were evaluated for bending moments in arrangements columns, beams and foundation elements, as well displacements and stresses in the earth under the beams and spot footing foundation of the columns.
Relacje jako element wartości dla klienta na przykładzie hoteli Grupy Hotelowej Orbis
- Edyta Gołąb-Andrzejak
2014 Pełny tekst PRACE NAUKOWE UNIWERSYTETU EKONOMICZNEGO WE WROCŁAWIU
W artykule poruszono kwestie związane z kształtowaniem wartości dla klienta hotelu w kontekście budowanych z nim związków lojalnościowych. Głównym celem było zbadanie znaczenia relacji w kształtowaniu wartości dla klienta. Rozważaniom przyświecał model wpływu relacji na wartość dla klienta, u którego podstaw leżało założenie, że wartość dostarczana klientowi decyduje o poziomie satysfakcji odczuwanej w kontaktach z przedsiębiorstwem. Klient usatysfakcjonowany zaś – w długiej perspektywie – staje się klientem lojalnym, z którym są budowane długotrwałe relacje. One zaś przekładają się na ocenę otrzymywanej wartości. Ponadto lojalny klient wyżej ocenia wartość dostarczaną mu przez usługodawcę, co w efekcie przekłada się na siłę budowanych z nim relacji. Obserwujemy tu swoistego rodzaju sprzężenie zwrotne. Na podstawie przeprowadzonych badań została podjęta próba wykazania, jak relacje budowane z gośćmi hotelowymi wpływają na wartość postrzeganą przez klienta. Badania przeprowadzono w wybranych hotelach trzygwiazdkowych Grupy Hotelowej Orbis.
Relation-based Wikipedia Search System for Factoid Questions Answering
- Adam Brzeski
- Tomasz Maria Boiński
2014 Pełny tekst International Journal of Innovative Research in Computer and Communication Engineering
In this paper we propose an alternative keyword search mechanism for Wikipedia, designed as a prototype solution towards factoid questions answering. The method considers relations between articles for finding the best matching article. Unlike the standard Wikipedia search engine and also Google engine, which search the articles content independently, requiring the entire query to be satisfied by a single article, the proposed system is intended to solve queries by employing information contained in multiple articles. Although still a keyword search, the method can be further employed in natural language questions answering, when accompanied with a question processing module. The method assumes that queries are formulated in a form of a list of Wikipedia articles. The possible solutions are then evaluated, however not by attempting to understand the meaning of the text, but by a simple method of estimating the distance between articles by measuring articles’ references or appearances in other articles, leading finally to returning a single article as an answer for the query.
Release and Transport of Toxic, Mobile Organic Compounds (Formaldehyde and Phenols) on an Arctic Glacier
- Krystyna Kozioł
- Marek Ruman
- Katarzyna Kozak
- Żaneta Polkowska
2014 Pełny tekst APCBEE Procedia
As a result of current deglaciation, the chemical cycles of many compounds, including toxic formaldehyde and phenols, are changing. However, the processes by which these chemicals are released have yet to be studied in situ. Here, we quantify fluxes of HCHO and phenols in a glacial catchment within one summer season, obtaining a net release from the glacier of 0.106 · 106 g formaldehyde and 0.255 · 106 g phenols, which can be interpreted as a combined result of summer deposition and glacier ice melt. Formaldehyde flux was shown to increase by 164% on a 250 m stretch of the stream flowing through an icing (an exposed former glacier bed area), whilst phenols have shown a smaller increase of 48%. Hence, the importance of glacial forefields in chemical cycle of toxic compounds is pronounced and requires further attention.
Reliable routing and resource allocation scheme for hybrid RF/FSO networks
- Jacek Rak
- Wojciech Molisz
2014
Significant success of wireless networks in the last decade has changed the paradigms of communication networks design. In particular, the growing interest in wireless mesh networks (WMNs) is observed. WMNs offer an attractive alternative to conventional cable infrastructures, especially in urban areas, where the cost of new installations is almost prohibitive. Unfortunately, the performance of WMNs is often limited by the cluttered RF spectrum and channel interference. Free space optical (FSO) technology is a possible solution for IP traffic connectivity, but weather-based disruptions, e.g., clouds, fog, and snow, highly affect the service availability in the network. However, FSO links can provide much higher data rates than RF links and do not interfere with RF links. In this paper, we first outline the important aspects that should be taken into account when determining allocation of network resources (link capacities) for the purpose of serving the demands. The latter part of the paper is to introduce the respective ILP model as well as heuristic algorithm to determine routing in hybrid RF/FSO networks with special focus on resistance of FSO links to weather-based disruptions.
Reliable underwater communication system for shallow coastal waters
- Jan Schmidt
2014 Pełny tekst HYDROACOUSTICS
This paper presents a reliable and robust low data rate spread spectrum approach which is implemented in the acoustic underwater communication system for shallow coastal waters. It shows operation assumptions of spread spectrum techniques based on the wellknown Shannon equation. It describes two methods of spread spectrum: frequency hopping spread spectrum and direct sequence spread spectrum; their block diagram and their characteristics are then listed to make comparisons. In short, adverse channel effect is analyzed on the expected operation of the system. I present the platform for the target implementation of the acoustic underwater communication system, which now has to allow continuous and easy development of stable algorithms.
Relikt ściany południowej wczesnogotyckiego budynku klasztornego dominikanów w Tczewie
- Piotr Samól
2014 Biuletyn Konserwatorski Województwa Pomorskiego
Artykuł dotyczy rozpoznania i analizy architektoniczno-historycznej odkrytego reliktu wolnostojącego klasztoru dominikanów w Tczewie (koniec XIII w.), który wraz z rozbudową kościoła (XIV w.) został wchłonięty przez obecną nawę. Obiekt obok kościoła św. Krzyża jest najstarszym rozpoznanym obiektem murowanym na terenie Tczewa.
Rendezvous of Distance-Aware Mobile Agents in Unknown Graphs
- Shantanu Das
- Dariusz Dereniowski
- Adrian Kosowski
- Przemysław Uznański
2014
We study the problem of rendezvous of two mobile agents starting at distinct locations in an unknown graph. The agents have distinct labels and walk in synchronous steps. However the graph is unlabelled and the agents have no means of marking the nodes of the graph and cannot communicate with or see each other until they meet at a node. When the graph is very large we want the time to rendezvous to be independent of the graph size and to depend only on the initial distance between the agents and some local parameters such as the degree of the vertices, and the size of the agent’s label. It is well known that even for simple graphs of degree Δ, the rendezvous time can be exponential in Δ in the worst case. In this paper, we introduce a new version of the rendezvous problem where the agents are equipped with a device that measures its distance to the other agent after every step. We show that these distance-aware agents are able to rendezvous in any unknown graph, in time polynomial in all the local parameters such the degree of the nodes, the initial distance D and the size of the smaller of the two agent labels l = min (l1, l2). Our algorithm has a time complexity of O(Δ(D + logl)) and we show an almost matching lower bound of Ω(Δ(D + logl/logΔ)) on the time complexity of any rendezvous algorithm in our scenario. Further, this lower bound extends existing lower bounds for the general rendezvous problem without distance awareness.
Rendezvous of Heterogeneous Mobile Agents in Edge-Weighted Networks
- Dariusz Dereniowski
- Łukasz Kuszner
- Adrian Kosowski
- Ralf Klasing
2014
We introduce a variant of the deterministic rendezvous problem for a pair of heterogeneous agents operating in an undirected graph, which differ in the time they require to traverse particular edges of the graph. Each agent knows the complete topology of the graph and the initial positions of both agents. The agent also knows its own traversal times for all of the edges of the graph, but is unaware of the corresponding traversal times for the other agent. The goal of the agents is to meet on an edge or a node of the graph. In this scenario, we study the time required by the agents to meet, compared to the meeting time T_OPT in the offline scenario in which the agents have complete knowledge about each others speed characteristics. When no additional assumptions are made, we show that rendezvous in our model can be achieved after time O(n T_OPT ) in a n-node graph, and that such time is essentially in some cases the best possible. However, we prove that the rendezvous time can be reduced to Θ(T_OPT) when the agents are allowed to exchange Θ(n) bits of information at the start of the rendezvous process. We then show that under some natural assumption about the traversal times of edges, the hardness of the heterogeneous rendezvous problem can be substantially decreased, both in terms of time required for rendezvous without communication, and the communication complexity of achieving rendezvous in time Θ(T_OPT ).
Renewable Energy Sources on the Polish Electrical Energy Market
- Paweł Bućko
2014 Pełny tekst Acta Energetica
Production of electricity from renewable energu sources in Poland is presented in the paper.The machanism of energy origin certifikates market and the proposal of mechanism modification are discused.
Reologia glikolizatów wytworzonych z odpadowych pianek polietero-uretanowych
- Ewa Głowińska
- Marcin Włoch
2014 Przemysł Chemiczny
Przedstawiono wyniki pomiarów reometrycznych glikolizatów wytwarzanych w procesie glikolizy piankowych odpadów polieterouretanowych. Glikolizy prowadzono przy stałym stosunku masowym odpadu do glikolu (6:1). Katalizatorem reakcji był octan potasu. Glikolizaty otrzymywano przy użyciu pięciu kolejnych glikoli począwszy od etano-1,2-diolu do heksano-1,6-diolu. Po zakończeniu glokolizy ze środowiska reakcji nie oddestylowywano pozostałości nieprzereagowanego glikolu. Zbadano wpływ glikolu na właściwości reologiczne glikolizatów poprzez wykreślenie krzywych płynięcia oraz krzywych lepkościowych. Dokonano opisu matematycznego charakterystyki reologicznej glikolizatów, poprzez dobór optymalnego modelu reologicznego wynikającego z korelacji punktów do krzywych obrazujących wpływ szybkości ścinania na zmiany lepkości glikolizatów. Wyniki z prac są istotne dla zapewnienia optymalnych warunków przetwórstwa glikolizatów z utworzonych z ich udziałem systemów poliuretanowych.
Reply to Maarit Johnson's Letter to the Editor
- Anna Maria Dåderman
- Beata Basińska
2014 Nordic Psychology
We wrote in response to the Letter to the Editor from Maarit Johnson regarding our article “Exploring the factor structure and the validity of the abbreviated Basic and Earning self-esteem Scales” (Dåderman & Basinska, 2013). We discussed two main issues: (a) the theory underlying the development of the longer (i.e., original) versions of the Basic and Earning SES, as well as the role of earning SE; and (b) the selection of items for the abbreviated scales.
Report vconcerning corrosion reasons of s/y Lunar hull surface and possible way of repair
- Jerzy Łabanowski
- Maria Głowacka
- Krzysztof Krzysztofowicz
2014
Dokonano oceny korozji kadłuba jednostki pływającej, przyczyn powstania korozji oraz zaproponowano sposoby naprawy miejsc skorodowanych.
Representation of magnetic hysteresis in single-phase transformer for circuit simulations
- Andrzej Wilk
2014
The paper presents a mathematical model for the hysteresis phenomenon in a multi-winding single-phase core type transformer. In the circuit transformer model, it is assumed that there is a flux common Φ to all windings as nonlinear and hysteretic function of the total currents Θ (Ampere turns) of all windings. To simulate magnetic behaviour of the iron core the feedback scalar Preisach model of hysteresis is developed. The Preisach Distribution Function (PDF) of the iron core material is approximated by functional series including two-dimensional Gauss expressions. Feedback function is represented by the third order polynomial. The hysteresis model has been successfully validated by comparing calculated and measured results of Φ-Θ hysteretic curve.
Resonance-Raman spectro-electrochemistry of intermediates in molecular artificial photosynthesis of bimetallic complexes
- Linda Zedler
- Julien Guthmuller
- Inês Rabelo
- Stephan Kupfer
- Sven Krieck
- Michael Schmitt
- Jürgen Popp
- Sven Rau
- Benjamin Dietzek
2014 CHEMICAL COMMUNICATIONS
The sequential order of photoinduced charge transfer processes and accompanying structure changes were analyzed by UV-vis and resonance-Raman spectroscopy of intermediates of a Ru(II) based photocatalytic hydrogen evolving system obtained by electrochemical reduction.