2019 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2019

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Sieć wielodomenowa wykorzystująca MPLS i SDN
- Krzysztof Zalewski
- Sylwester Kaczmarek
- Jacek Andrzej Litka
2019 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne
Technologia Wieloprotokołowej Komutacji Etykietowej (MPLS – MultiProtocol Label Switching) dostarcza odpowiednie mechanizmy wspierające proces zachowania jakości usług, jednak wymaga nadrzędnego elementu sterującego. Takim elementem może być kontroler zrealizowany w koncepcji Sieci Definiowanych Programowo (SDN – Software Defined Networking), wprowadzający abstrakcję, rozdzielającą płaszczyznę przekazywania od płaszczyzny sterowania. W niniejszym artykule przedstawiono sposób połączenia obu technologii w ramach jednej sieci wielodomenowej.
Signal Processing in the Investigation of Two-phase Liquid-gas Flow by Gamma-ray Absorption
- Robert Hanus
- Marcin Zych
- Marek Jaszczur
- Anna Szlachta
- Anna Golijanek-Jędrzejczyk
2019
n this paper, the use of the gamma-absorption method applied in the investigation of the two-phase liquid-gas flow in the pipeline is described. An example of its application to the air transported by water in a horizontal pipeline is evaluated. In the measurements, Am-241 radioactive sources and probes with Nal (Tl) scintillation crystals have been used. The signals from the radiometric set were used to determine the velocity of the dispersed phase, void fraction and for identification of flow regime. In the latter case, artificial neural networks were applied. Results of the selected experiments carried out on a laboratory stand are presented.
Signal Reconstruction from Sparse Measurements Using Compressive Sensing Technique
- Beata Pałczyńska
2019
The paper presents the possibility of applying a new class ofmathematical methods, known as Compressive Sensing (CS) for recovering thesignal from a small set of measured samples. CS allows the faithful recon-struction of the original signal back from fewer random measurements bymaking use of some non-linear reconstruction techniques. Since of all thesefeatures, CSfinds its applications especially in the areas where, sensing is timeconsuming or power constrained. An electromagnetic interference measurementis afield where the CS technique can be used. In this case, a sparse signaldecomposition based on matching pursuit (MP) algorithm, which decomposes asignal into a linear expansion of element chirplet functions selected from acomplete and redundant time-frequency dictionary is applied. The presentedpaper describes both the fundamentals of CS and how to implement MP for CSreconstruction in relation to non-stationary signals.
Signals features extraction in radioisotope liquid-gas flow measurements using wavelet analysis
- Robert Hanus
- Marcin Zych
- Barbara Wilk
- Marek Jaszczur
- Dariusz Świsulski
2019 Pełny tekst EPJ Web of Conferences
Knowledge of the structure of a flow is significant for the proper conduct of a number of industrial processes. In this case, a description of a two-phase flow regimes is possible by use of the time-series analysis in time, frequency and state-space domain. In this article the Discrete Wavelet Transform (DWT) is applied for analysis of signals obtained for water-air flow using gamma ray absorption. The presented method was illustrated by use data collected in experiments carried out on the laboratory hydraulic installation with a horizontal pipe, equipped with two Am-241 radioactive sources and scintillation probes with NaI(Tl) crystals. Signals obtained from detectors for slug, plug, bubble, and transitional plug – bubble flows were considered in this work. The recorded raw signals were analyzed and wavelet energy was extracted using multiresolution analysis. It was found that energies of wavelet approximation at 1-5 levels are useful to recognize the structure of the flow.
Similarities and differences in d6 low-spin ruthenium, rhodium and iridium half-sandwich complexes: synthesis, structure, cytotoxicity and interaction with biological targets
- Agnieszka Gilewska
- Barbara Barszcz
- Joanna Masternak
- Katarzyna Kazimierczuk
- Jerzy Sitkowski
- Joanna Wietrzyk
- Eliza Turlej
2019 Pełny tekst JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY
In this paper, we discussed the similarities and diferences in d6 low-spin half-sandwich ruthenium, rhodium and iridium complexes containing 2,2′-biimidazole (H2biim). Three new complexes, {[RuCl(H2biim)(η6 -p-cymene)]PF6}2·H2O (1), [(η5 - Cp)RhCl(H2biim)]PF6 (2), and [(η5 -Cp)IrCl(H2biim)]PF6 (3), were fully characterized by CHN, X-ray difraction analysis, UV–Vis, FTIR, and 1 H, 13C and 15N NMR spectroscopies. The complexes exhibit a typical pseudooctahedral piano-stool geometry, in which the aromatic arene ring (p-cymene or Cp) forms the seat, while the bidentate 2,2′-biimidazole and chloride ion form the three legs of the piano stool. Moreover, the cytotoxic activities of the compounds were examined in the LoVo, HL-60, MV-4-11, MCF-7 human cancer cell lines and BALB/3T3 normal mouse fbroblasts. Notably, the investigated complexes showed no cytotoxic efects towards the normal BALB/3T3 cell line compared to cisplatin, which has an IC50 value of 2.20 µg. Importantly, 1 displayed the highest activity against HL-60 (IC50 4.35 µg). To predict a binding mode, we explored the potential interactions of the metal complexes with CT-DNA and protein using UV absorption and circular dichroism. The obtained data suggest that the complexes could interact with CT-DNA via an outside binding mode. Moreover, binding of the complexes with the GSH via UV–Vis and ESI mass spectra was determined. Comparative studies have shown that the rhodium complex (2) is the most GSH reactive, which is probably responsible for its deactivation towards LoVo and MCF-7 tumour cells. The infuence of the metal ion on the biological activity of isostructural Rh(III) and Ir(III) complexes was an important goal of the presented investigation.
Simplified Map-based Selection of Optimal Spindle Speeds When Milling Complex Structures
- Krzysztof Jan Kaliński
- Marek Galewski
- Michał Mazur
2019 Pełny tekst
In the paper a method for selecting optimal spindle speeds for complex structures during milling operations is presented. It is based on the selection of the spindle speed in accordance with a simple equation resulting from the minimisation of vibration energy, which leads to the minimisation of the work of cut-ting forces presented in previous elaborations by the authors [1]. Optimal spindle speeds are obtained for many points selected on machined surface thanks to the results of the modal test. The effectiveness of the proposed method is verified based on the results of experimental research. Reduction of vibration level, improvement of surface quality and reduction of milling time were obtained.
Simulation of Direct-Sequence Spread Spectrum Data Transmission System for Reliable Underwater Acoustic Communications
- Iwona Kochańska
- Jan Schmidt
2019 Pełny tekst Vibrations in Physical Systems
Underwater acoustic communication (UAC) system designers tend to transmit as much information as possible, per unit of time, at as low as possible error rate. It is a particularly difficult task in a shallow underwater channel in which the signal suffers from strong time dispersion due to multipath propagation and refraction phenomena. The direct-sequence spread spectrum technique (DSSS) applied successfully in the latest standards of wireless communications, gives the chance of reliable data transmission with an acceptable error rate in a shallow underwater channel. It utilizes pseudo-random sequences to modulate data signals, and thus increases the transmitted signal resilience against the inter symbol interference (ISI) caused by multipath propagation. This paper presents the results of simulation tests of DSSS data transmission with the use of different UAC channel models using binary spreading sequences.
Simulations of air and water flow in a model dike during overflow experiments
- Witold Tisler
- Wioletta Gorczewska-Langner
- Leśniewska Danuta
- Maciejewski Stanisław
- Rafał Ossowski
- Adam Szymkiewicz
2019 Pełny tekst COMPUTATIONAL GEOSCIENCES
Flow in flood dikes, earth dams, and embankments occurs in variably saturated conditions, with pores of the earth material filled partly with water and partly with air. In routine engineering analysis, the influence of pore air is neglected and the air pressure is assumed equal to atmospheric. In some circumstances, for example, during overtopping of the dike by water, the effect of pore air on water flow and stability of the structure can be important. These features cannot be captured with the commonly used Richards equation. In this paper, we analyze earlier experiments on the overtopping of a model dike made of fine sand. During the experiments, a significant amount of air was trapped near the outer slope of the dike, which later escaped through a fracture formed in wet sand. The observations were compared with numerical simulations using the Richards equation and the two-phase immiscible flow model. The deformation and damage of the dike were not modelled, but the initial evolution of the entrapped air pressure (before damage occurred) was in a good agreement with two-phase flow simulations.
Singular Surface Curves in the Resultant Thermodynamics of Shells
- Violetta Konopińska-Zmysłowska
- Victor Eremeev
2019
Within six-parameter shells theory we discuss the governing equations of shells with material or non-material singular curves. By singular curve we mean a surface curve where are discontinuities in some surface fields. As an example we consider shells with junctions and shells undergoing stress-induced phase transitions.
Size effect in concrete beams under bending – influence of the boundary layer and the numerical description of cracks
- Ireneusz Marzec
- Jerzy Bobiński
2019 Pełny tekst MATEC Web of Conferences
In the paper the size effect phenomenon in concrete is analysed. The results of numerical simulations of using FEM on geometrically similar un-notched and notched concrete beams under bending are presented. Concrete beams of four different sizes and five different notch heights under three-point bending test were simulated. In total 18 beams were analysed. Two approaches were used to describe cracks in concrete. First, eXtended Finite Element Method (XFEM) describing cracks as discrete cohesive ones with bilinear softening was chosen. Alternatively, an elasto-plastic constitutive law with Rankine criterion, associated flow rule and bilinear softening was defined. In order to ensure mesh-independent FE results, a non-local theory in an integral format as a regularisation technique was applied in the softening regime. In both approaches the influence of the decrease of the material parameters (mainly fracture energy) in the boundary layer on obtained maximum loads was studied. Additionally the influence of the averaging method in non-local plasticity was also examined. Obtained results were compared with experimental outcomes available in literature.
Size Exclusion Coupled to Reversed Phase Liquid Chromatography for the Characterization of Cranberry Products
- Inal Bakhytkyzy
- Oscar Nuñez
- Javier Saurina
2019 Food Analytical Methods
A combination of solvent extraction, size exclusion purification, and reversed-phase liquid chromatography with UV absorption and fluorescence detection was here used for the determination of flavan-3-ols and related oligomeric compounds in cranberry products. The method relied on robust, simple, and inexpensive instrumental equipment present in most of routine analytical laboratories. Sample extracts in methanol/water/hydrochloric acid solution (60:39:1, v/v/v) were subjected to size-exclusion chromatography (SEC) using Sephadex LH-20 as the sorbent to separate simple phenolic and oligomeric components. As a novel aspect of this work, the implementation of the SEC process in a reusable packed column was practically and economically highly advantageous. Fractions were analyzed by reversed-phase chromatography using a C18 core-shell analytical column and 0.1% formic acid aqueous solution and methanol as the components of the mobile phase. Chromatograms were recorded by UV absorption spectroscopy at 280 nm and by fluorescence spectroscopy at λex 280 nm/λem 347 nm. The method was applied to the determination of flavan-3-ols in various cranberry samples. Catechin, epicatechin, and procyanidins A2 and B2 were found in different amounts depending on the cranberry varieties.
Size-Controlled Synthesis of Pt Particles on TiO2 Surface: Physicochemical Characteristic and Photocatalytic Activity
- Anna Zielińska-Jurek
- Zhishun Wei
- Marcin Janczarek
- Izabela Wysocka
- Kowalska Ewa
2019 Pełny tekst Catalysts
Different TiO2 photocatalysts, i.e., commercial samples (ST‐01 and P25 with minority of rutile phase), nanotubes, well‐crystallized faceted particles of decahedral shape and mesoporous spheres, were used as supports for deposition of Pt nanoparticles (NPs). Size‐controlled Pt NPs embedded in TiO2 were successfully prepared by microemulsion and wet‐impregnation methods. Obtained photocatalysts were characterized using XRD, TEM, X‐ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) specific surface area, DR/UV‐vis and action spectrum analysis. The effect of deposition method, amount of Pt precursor and TiO2 properties on size, distribution, and chemical states of deposited Pt NPs were investigated. Finally, the correlations between the physicochemical properties and photocatalytic activities in oxidation and reduction reactions under UV and Vis light of different Pt‐TiO2 photocatalysts were discussed. It was found that, regardless of preparation method, the photoactivity mainly depended on platinum and TiO2 morphology. In view of this, we claim that the tight control of NPs’ morphology allows us to design highly active materials with enhanced photocatalytic performance. Action spectrum analysis for the most active Pt‐modified TiO2 sample showed that visible light‐induced phenol oxidation is initiated by excitation of platinum surface plasmon, and photocatalytic activity analysis revealed that photoactivity depended strongly on morphology of the obtained Pt‐modified TiO2 photocatalysts
Skoczek narciarski, telemark, rysunek na papierze, tusz, 21 x 29 cm, 2017
- Patryk Różycki
2019
Skoczek narciarski, telemark, rysunek na papierze, tusz, 21 x 29 cm, 2017, wystawa kolekcji sztuki współczesnej Galerii Ul, z okazji pierwszych urodzin Galerii,
SMART AND RESILIENT CITIES – NEW CHALLENGES FOR POLISH CITIES IN TERMS OF 2020 BUILDING ENERGY EFFICIENCY AND CLIMATE CHANGE ACTION.
- Julia Kurek
2019
Global climate change action along with energy efficiency optimizations are becoming increasingly pressing principles in terms of moving towards sustainable development. As a member of EU and UN Poland is also obliged to follow restricted rules concerning energy efficiency of buildings which come to force in 2020. To meet new goals, innovative approaches - like moving towards smart and resilient cities -may be required. Through literature review method this article strives to identify main Polish cities challenges related to extreme weather events and air pollution along with identifying potentials in moving towards smart and resilient cities approaches. This paper provides theoretical approach on the background of climate change and energy efficiency aspects along with critical assessment of resilient and smart cities concepts as potential solutions for Polish cities in 2020. As a method in this article, literature review, statistical data analyzes were adopted, because they allowed the most to analyze the topic and reach to objective facts.
Smart Blue Cities
- Aleksander Orłowski
- Edward Szczerbicki
2019 Pełny tekst EUROPA XXI
This paper presents the concept of Smart Cities from the perspective of those located by water, considering if there are more major differences in the way the concept is implemented in coastal cities, as opposed to those located anywhere else. It proves possible to point to such differences, in relation to the three key areas of mobility, the environment and living. Further consideration is given to specific legal and cross-cultural challenges – like excessive tourism and issues of short-term rental – as these appear from the Smart City perspective; and relevant mobility challenges are also addressed. The article further refers to aspects the Smart City and Blue Growth concepts have in common, as well as to areas in which coordination of the two will be necessary. Ultimately, conclusions are arrived at on the basis of research results for 10 large cities in Poland, the readiness of their City Offices to implement the Smart City concept having been the subject of verification.
Smart Cities Concept: Smart Mobility Indicator
- Aleksander Orłowski
- Patrycja Romanowska
2019 Pełny tekst CYBERNETICS AND SYSTEMS
This work attempts to analyze problems resulting from the lack of possibility to assess the effectiveness of the implementation of “Smart Mobility” solutions, which represent one of the cornerstones of Smart Cities, from the point of view of city hall offices. The work presents existing Smart Mobility evaluation solutions, discusses their drawbacks, and then proposes a new indicator. The final part of the work presents assumptions with regard to the verification of the indicator and research work planned for the future.
Smart Virtual Product Development (SVPD) to Enhance Product Manufacturing in Industry 4.0
- Muhammad Ahmed
- Cesar Sanin
- Edward Szczerbicki
2019 Pełny tekst Procedia Computer Science
This paper presents a system capable of enhancing product development process for industrial manufactured products. This system is known as Smart Virtual Product Development (SVPD), and it helps in decision making by using explicit knowledge of formal decision events. It stores and reuses the past decisional events or sets of experiences related to different activities involved in industrial product development process i.e. product design, manufacturing, and product inspection. This system can be potentially used in large enterprises manufacturing a range of similar products in mass production, or a group of Small and medium enterprises (SMEs). This research shows that how product manufacturing can be enhanced by using SVPD in Industry 4.0, where cyber-physical systems have to play the key role. The analysis of basic concepts and implementation method proves that this is an expert system facilitating product manufacturing which can play a vital role towards Industry 4.0.
Smoothed transition curve for railways
- Władysław Koc
2019 Pełny tekst Przegląd Komunikacyjny
The work draws attention to the existing situation in the area of transition curves used in the geometric layouts of the railway track. Difficulties in the practical implementation and maintenance of very small horizontal ordinates of the transition curve and the ordinates of the gradient due to cant in the initial section, appearing on smooth transition curves, were indicated. The main reason for this situation was the excessive smoothing of the curvature in their initial section. Employing the method of curvature identification by differential equations, a new form of the curve was obtained, which was referred to as the "smoothed transition curve". A definite advantage of this curve was shown, from the implementation point of view, over representing the smooth transition curves of the Bloss curve. . It seems that it could successfully compete with the commonly used clothoid, to which it is similar in the initial section, while it differs significantly along its further length, especially in the final section, where it provides a gentle entry from the transition curve into a circular arc.
Social learning and knowledge flows in cluster initiatives, In: Sanz S.C., Blanco F.P., Urzelai B. (Eds). Human and Relational Resources (pp. 44-45). the 4th International Conference on Clusters and Industrial Districts CLUSTERING, University of Valencia, Spain, May 23–24 (ISBN: 978-84-09-11926-4).
- Małgorzata Rozkwitalska
- Anna Lis
2019
Purpose – The purpose of the paper is to explore how learning manifests and knowledge flows in cluster initiatives (CIs) due to interactions undertaken by their members. The paper addresses the research question of how social learning occurs and knowledge flows in CIs. Design/methodology/approach – The qualitative study of four cluster initiatives helped to identify various symptoms of social learning and knowledge flows in CIs. Findings – The study identifies four types of communities of practice in CIs: dead souls, participants, cooperators and locomotives. Additionally, it documents different manifestations of social learning and knowledge flows in each of them, namely one-way or two-way information transferring and raising awareness, demonstrating and inspiring, or motivating and educating, i.e. from the basic practice to the most advanced one. It also shows that while potentially every member of CIs has access to these practices, merely a limited number of members is actually involved. It may suggest that learning and knowledge flows in CIs are selective and some CIs’ members accept a more peripheral role in CIs. Research limitations/implications – The research shows the application of communities of practice theory to the analysis of CIs and learning and knowledge flows within them. 45 Nevertheless, the qualitative approach in the study does not allow for generalizing the findings. Practical implications – The study emphasizes that at each stage of the development of CIs, the learning process is carried out on the basis of interactions created among members. Therefore, it is important to support ‘soft’ forms of cooperation within CIs – involving members in activities as well as developing interactions. Originality/value – The research fills in the gap concerning symptoms of social learning and knowledge flows in CIs. It shows that selectiveness in this process can be observed. The study applies the community of practice approach to study the phenomenon of learning in CIs.
Soft Real-Time Communication with WebSocket and WebRTC Protocols Performance Analysis for Web-based Control Loops
- Tomasz Karla
- Jarosław Tarnawski
2019
The web browser has become an access window for content and services. The browser is available on almost any device connected to the network, regardless of its intended use: desktop, mobile device, computing server, e-book reader etc. Browsers are used by people to read news, contact the world, to check a bank account, register a visit at the doctor, watching video content, electronic purchases, using web versions of the office package, etc. Universal availability, uniformity and intuitive handling, independence from hardware and operating systems are advantages over executable programs. Current applications in the field of automation include, for example, the implementation of user interfaces to present the state of the process and to accept operators' instructions in the form of web pages. The article considers network services and web browser as elements of the control loop. At least soft real-time (RT) work is needed for such applications. With the development of network protocols, the issue of providing RT transmission has appeared. There are currently two leading protocols taking into account the time aspects: WebSocket and WebRTC. The article compares their properties (mainly communication delays) in various network configurations and assess their suitability as an infrastructure of control systems. Selected techniques allowing to handle with delays in control loops are presented. Two control loops (simple PID loop and a multidimensional DMC) on web platform case studies are presented.