2018 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2018

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Shipping Safety Management on Polish Inland Waterways
- Patrycja Jerzyło
- Paulina Rekowska
- Kujawski Artur
2018 Archives of Transport System Telematics
Over the past years, the role of inland waterway transport has increased compared to other modes of transport. The increasing intensity of the inland vessel traffic significantly affects the safety of navigation. The article analyses the main causes of accidents and incidents that occurred on the Odra Waterway and Lower Vistula. The authors have classified those accidents and suggested possible directions for the development of inland waterway management in order to improve its efficiency. Navigationally critical areas in the lower section of the rivers Odra and Vistula have been indicated. These areas should be taken into account in long-term planning of the inland shipping development to ensure transport safety.
Shub’s conjecture for smooth longitudinal maps of S^m
- Grzegorz Graff
- Michał Misiurewicz
- Piotr Nowak-Przygodzki
2018 JOURNAL OF DIFFERENCE EQUATIONS AND APPLICATIONS
Let f be a smooth map of the m-dimensional sphere Sm to itself, preserving the longitudinal foliation. We estimate from below the number of fixed points of the iterates of f , reduce Shub’s conjecture for longitudinal maps to a lower dimensional classical version, and prove the conjecture in case m = 2 and in a weak form for m = 3.
Signal filtering method of the fast-varying diesel exhaust gas temperature
- Patrycja Puzdrowska
2018 Pełny tekst Combustion Engines
The paper presents the problem of the impact of external distortions originating on laboratory test stands on the results of measurements of fast-varying diesel exhaust gas temperature. It has been stressed how significant the aspect of the test stand adaptation is during an experiment to ensure the smallest possible impact. This paper, however, focuses on the methods of mathematical processing of a signal recorded during experimental research of a real object. The most significant parameter requiring filtering is the fast-varying exhaust gas temperature in the engine exhaust channel. Methods of mathematical processing adequate to this type of distorted signal have been presented, particularly those that can be used in the Matlab environment and consisting in averaging of the obtained curves of temperature changes. The results of the application of these methods have also been presented on actual curves recorded during laboratory tests and their evaluation has been made.
Simple Computational Methods in Predicting Limit Load of High-Strength Cold-Formed Sections due to Local Buckling: A Case Study
- Paweł Michał Bielski
- Leszek Samson
- Oskar Wysocki
- Jacek Czyżewicz
2018 Pełny tekst Polish Maritime Research
Cold-formed thin-walled sections are prone to local buckling caused by residual stresses, geometrical imperfections and inconsistency of material properties. We present a real case of buckling failure and conduct a numerical and experimental study aimed to identify methods capable of predicting such failures. It is important because designers of structures are getting more FEA-oriented and tend to avoid lengthy procedures of cold-formed structures design. Currently adopted methods are complicated and require patience and caution from a designer which is reasonable in case of the most important structural members but not necessarily so in ordinary design. Since it is important, we offer an insight into several FEA and manual methods which were sufficient to predict the failure while remaining fairly simple. Using a non-uniform partial safety factor was still necessary. We hope that this paper will be of interest for people performing a lot of routine analyses and worrying about reliability of their computations.
Simple Fractal Calculus from Fractal Arithmetic
- Diederik Aerts
- Marek Czachor
- Maciej Kuna
2018 Pełny tekst REPORTS ON MATHEMATICAL PHYSICS
Non-Newtonian calculus that starts with elementary non-Diophantine arithmetic operations of a Burgin type is applicable to all fractals whose cardinality is continuum. The resulting definitions of derivatives and integrals are simpler from what one finds in the more traditional literature of the subject, and they often work in the cases where the standard methods fail. As an illustration, we perform a Fourier transform of a real-valued function with Sierpiński-set domain. The resulting formalism is as simple as the usual undergraduate calculus.
Simplified method of applying loads to flat slab floor structural model
- Maciej Tomasz Solarczyk
- Andrzej Ambroziak
2018 Pełny tekst MATEC Web of Conferences
The article analyses the impact of the live load position on the surface of a reinforced concrete flat slab floor of 32.0 m × 28.8 m. Four variants of a live load position are investigated: located on the entire concrete slab, set in a chessboard pattern, applied by bands and imposed separately in each of the slab panels. Conclusions are drawn upon differences in bending moments, the time of calculation and the size of output files. The problems in the interpretation of results are presented too. A procedure is presented to model the reinforced concrete structures in computational programs. The recommendations of the Eurocodes are presented regarding to load combinations in the Ultimate Limit State (ULS). Convergence analysis of the finite element mesh is carried out to verify the obtained results. The law status on the implementation of the Building Information Modelling (BIM) technology in Poland points out significant time savings in the application of this technology.
Simulation of Life Raft Motions on Irregular Wave - An Analysis of Situations Leading to Raft Capsizing
- Olga Kazimierska
2018 Pełny tekst Polish Maritime Research
Successful rescue action at sea is based on a. o. a correct choice of rescue means and their reliability. Operational characteristics of life-saving appliances determine their performance in a given water area. Therefore they affect duration time of rescue action and decide this way on survival time of shipwrecked persons. This paper presents impact of characteristics of circular inflatable life rafts on their dynamics in a given sea environment. Particular issues dealing with raft motion were analyzed and their solutions were then presented in the form of computer programs built into MATLAB environment. The programs operate on the open choice basis– the user is requested to introduce data of a raft to be investigated. The program clearly informs which units should be used for the data. The obtained results allow to limit survivours searching area and simultaneously form the basis for working out a model of searched object drift motion. In this work the use was made of the results obtained from the KBN research project No. 4T12C03827 in which an attempt was made to analyzing capsize probability of a raft at given sea states. The raft investigated in the project is also used as a reference raft in the computer programs developed in this work.
Simulation of the Dynamics of Renewable Energy Sources with Energy Storage Systems
- Robert Małkowski
- Paweł Bućko
- Marcin Jaskólski
- Wojciech Pawlicki
- Alicja Stoltmann
2018
The intermittency of renewable energy sources (RES) constitutes a challenge for effective power system control. Fossil-fuel-based units offering ancillary power services to meet the short-term power imbalance are a financial and environmental burden for the society. Energy storage systems (ESS) can be the solution in view of the electricity market development and growing environmental concern. The major questions are, in what circumstances participation in the day-ahead market (DAM) by means of the RES-ESS co-operation is technically feasible and how to size ESS for PV participation in DAM. This paper is an attempt of addressing these questions. To provide the answer, the simulation model of solar power generation system with battery ESS (BESS) was developed using DIgSILENT Power Factory environment.
Simulation-driven size-reduction-oriented design of multi-band antennas by means of response features
- Sławomir Kozieł
- Adrian Bekasiewicz
2018 IET Microwaves Antennas & Propagation
This study addresses the problem of explicit size reduction of multi-band antennas by means of simulation-driven optimisation. The principal difficulty of electromagnetic (EM)-based miniaturisation of multi-band antennas is that several resonances have to be controlled independently (both in terms of their frequency allocation and depth) while attempting to reduce physical dimensions of the structure at hand. The design method of choice in this work is feature-based optimisation (FBO) framework. The methodology has been shown as appropriate for handling multi-band antenna responses. The primary objective of the optimisation process is the footprint area of the antenna. At the same time, design requirements pertinent to reflection characteristics are handled by means of a penalty function approach. The properties of the FBO framework, namely ‘flattening’ of the functional landscape, allows to keep the design optimisation costs at acceptable levels of few dozens of evaluation of the EM simulation model of the antenna. For the sake of demonstration, two antenna structures are considered, a dual-band patch antenna, and a triple-band dipole antenna. Considerable size-reduction ratios are achieved, over 50% and almost 30% for the first and the second structures, respectively. Numerical results are validated experimentally.
Simulations of freshwater lens recharge and salt/freshwater interfaces using the HYDRUS and SWI2 packages for MODFLOW
- Adam Szymkiewicz
- Anna Gumuła-Kawęcka
- Jirka Simunek
- Bertrand Leterme
- Sahila Beegum
- Beata Jaworska-Szulc
- Małgorzata Pruszkowska-Caceres
- Wioletta Gorczewska-Langner
- Rafael Angulo-Jaramillo
- Diederik Jacques
2018 Pełny tekst Journal of Hydrology and Hydromechanics
The paper presents an evaluation of the combined use of the HYDRUS and SWI2 packages for MODFLOW as a potential tool for modeling recharge in coastal aquife rs subject to saltwater intrusion. The HYDRUS package for MODFLOW solves numerically the one-dimensional form of the Richards equation describing water flow in variably- saturated media. The code computes groundwater recharge to or capillary rise from the groundwater table while considering weather, vegetation, and soil hydraulic property data. The SWI2 package represents in a simplified way variable-density flow associated with saltwater intrusion in coastal aquifers. Combining these two packages within the MODFLOW framework provides a more accurate description of vadose zone processes in subsurface systems with shallow aquifers, which strongly depend upon infiltration. The two packages were applied to a two-dimensional problem of recharge of a freshwater lens in a sandy peninsula, which is a typical geomorphologic form along the Baltic and the North Sea coasts, among other places. Results highlighted the sensitivity of calculated recharge rates to the temporal resolution of weather data. Using daily values of precipi tation and potential evapotranspiration produced average recharge rates more than 20% larger than those obtained with weekly or monthly averaged weather data, leading to different trends in the evolution of freshwater-saltwater interfaces. Root water uptake significantly influenced both the recharge rate and the position of the freshwater-saltwater interface. The results were less sensitive to changes in soil hydraulic parameters, which in our study were found to affect average yearly recharge rates by up to 13%.
Simultaneous determination of ibuprofen and its metabolites in complex equine urine matrices by GC-EI-MS in excretion study in view of doping control
- Emilia Waraksa
- Marzena Wójtowicz-zawadka
- Dorota Kwiatkowska
- Anna Jarek
- Anna Małkowska
- Robert Wrzesień
- Jacek Namieśnik
2018 JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
A novel assay for the simultaneous determination of ibuprofen (IBU) and its four probable metabolites, 1-hydroxyibuprofen (1-OH IBU), 2-hydroxyibuprofen (2-OH IBU), 3-hydroxyibuprofen (3-OH IBU) and carboxyibuprofen (CBX IBU) in equine urine samples with the application of Gas Chromatography-Electron Ionization-Mass Spectrometry (GC-EI-MS) has been developed and elaborated. The new approach for sample preparation including minimizing matrix effects by the application of weak cation exchange solid-phase extraction together with strong cation exchange solid-phase extraction has been applied. The GC-EI-MS method was validated to demonstrate specificity, matrix effect, linearity, limit of detection (LOD) and quantification (LOQ), precision, trueness, carry-over and stability by using the matrix-matched quality control samples. Additionally, extraction yield was evaluated. The assay achieved the LOQ of 1.75 μg mL−1, 0.62 μg mL−1, 4.15 μg mL−1, 0.58 μg mL−1 and 4.04 μg mL−1 for IBU, 1-OH IBU, 2-OH IBU, 3-OH IBU and CBX IBU, respectively. The developed method has been successfully applied to the excretion study in horses, in which a single oral IBU dose was administered to twelve horses (mares and geldings) and equine urine samples were collected for 5 or 6 days after the drug administration. Data on the detection and determination of three IBU metabolites, 2-OH IBU, 3-OH IBU and CBX IBU in equine urine samples has been presented for the first time. The obtained results indicated the rapid excretion of IBU and its metabolites that were detectable only in the first day after the drug administration. IBU was mainly the most abundant compound detected in equine urine samples (with two exceptions in the case of samples collected from two horses, for which the highest instrumental responses were obtained for CBX IBU). The received results have indicated that two major IBU metabolites, CBX IBU and 2-OH IBU can be important markers for the IBU abuse in view of doping control in equestrian sports.
Simultaneous grouping and ranking with combination of SOM and TOPSIS for selection of preferable analytical procedure for furan determination in food
- Renata Marcinkowska
- Stefan Tsakovski
- Aurore Lavanu
- Jacek Namieśnik
- Marek Tobiszewski
2018 TALANTA.The International Journal of Pure and Applied Analytical Chemistry
Novel methodology for grouping and ranking with application of self-organizing maps and multicriteria decision analysis is presented. The dataset consists of 22 objects that are analytical procedures applied to furan determination in food samples. They are described by 10 variables, referred to their analytical performance, environmental and economic aspects. Multivariate statistics analysis allows to limit the amount of input data for ranking analysis. Assessment results show that the most beneficial procedures are based on microextraction techniques with GC-MS final determination. It is presented how the information obtained from both tools complement each other. The applicability of combination of grouping and ranking is also discussed.
Single and Dual-GPU Generalized Sparse Eigenvalue Solvers for Finding a Few Low-Order Resonances of a Microwave Cavity Using the Finite-Element Method
- Adam Dziekoński
- Michał Mrozowski
2018 Pełny tekst RADIOENGINEERING
This paper presents two fast generalized eigenvalue solvers for sparse symmetric matrices that arise when electromagnetic cavity resonances are investigated using the higher-order finite element method (FEM). To find a few loworder resonances, the locally optimal block preconditioned conjugate gradient (LOBPCG) algorithm with null-space deflation is applied. The computations are expedited by using one or two graphical processing units (GPUs) as accelerators. The performance of the solver is tested for single and dual GPU hardware setups, making use of two types of GPU: NVIDIA Kepler K40s and NVIDIA Pascal P100s. The speed of the GPU-accelerated solvers is compared to a multithreaded implementation of the same algorithm using a multicore central processing unit (CPU, Intel Xeon E5-2680 v3 with twelve cores). It was found that, even for the least efficient setups, the GPU-accelerated code is approximately twice as fast as a parallel CPU-only implementation
Singlet Exciton Diffusion in Vacuum-Evaporated Films of Amine-Based Materials as Studied by Photocurrent and Photoluminescence Quenching Methods
- Daniel Karol Pelczarski
- Piotr Jerzy Grygiel
- Waldemar Stampor
2018 PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
The singlet exciton diffusion lengths are determined by the photoconductivity as well as the luminescence surface quenching technique, in vacuum‐evaporated layers of (4,4′,4″‐tris(N‐(3‐methylphenyl)‐N‐phenylylamino) triphenylamine) (m‐MTDATA), 4,4′,4″‐tris[2‐naphthyl(phenyl)amino] triphenylamine (2TNATA), and N,N′‐diphenyl‐N,N′‐bis(3‐methylphenyl)‐[1,1′‐biphenyl]‐4,4′‐diamine (TPD) which are frequently used for fabrication of electroluminescent and photovoltaic devices. The values are found to be as high as (30 ± 10) nm in 2TNATA and m‐MTDATA, as well as (46 ± 9) nm in TPD films. The corresponding singlet diffusion coefficients of the range between 1 × 10−3 and 1 × 10−2 cm2 s−1, according to a comprehensive study undertaken, are assigned to a sizable electronic coupling induced by strong interactions of intra‐ and inter‐molecular origin in the investigated materials.
Size effect in concrete under splitting tension
- Jan Suchorzewski
- Andrzej Tejchman-Konarzewski
2018
The size effect is a fundamental phenomenon in concrete materials. It denotes that both the nominal structural strength and material ductility always decrease with increasing element size under tension. In the paper splitting tensile tests on cylindrical concrete specimens with the different diameter were carried out. Two types of the loading strip (plywood board and steel cylinder) were used. The concrete strength and ductility decreased with increasing specimen diameter. For large concrete specimens a clear snap-back occurred. The experiments were simulated with the spherical discrete element method (DEM) under two-dimensional conditions. In the calculations, concrete was assumed as a four-phase composite material including aggregate, cement matrix, interfacial transitional zones (ITZs) and macro-voids. The process of micro- and macro-cracking was studied in detail for various failure modes. The macroscopic curves and shapes of cracks were directly compared with the laboratory test outcomes.
Size reduction of ultra-wideband antennas with efficiency and matching constraints
- Sławomir Kozieł
- Adrian Bekasiewicz
- Leifur Leifsson
2018 INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS
Antenna design is a multifaceted task that involves handling of various performance figures concerning both electrical performance of the structure as well as its geometry. Simultaneous control of several objectives through rigorous optimization is very challenging and virtually impossible through conventional approaches such as parameter sweeping. In this work, we investigate size reduction of ultra‐wideband antenna structures while taking into account the reflection response and total efficiency. Available design trade‐offs concerning the antenna footprint, its wideband matching, and efficiency are identified through numerical optimization. More specifically, the goal is to identify designs that exhibit the minimum possible footprint while maintaining the maximum in‐band reflection and average efficiency within the prescribed thresholds. This is realized by appropriate formulation of the objective function exploiting a penalty function approach. Our methodology is demonstrated using an ultra‐wideband monopole antenna example. As an extension, a 3‐objective Pareto set is further generated using surrogate modeling and multi‐objective evolutionary algorithm. A set of designs generated this way provides a designer with a comprehensive knowledge about the capabilities of a given antenna structure and facilitates a decision‐making process driven by a particular application and performance requirements
Skażenie powierzchni ścierniwem po obróbce przez docieranie zagrożeniem dla eksploatacji maszyn
- Adam Barylski
2018
Przedstawiono metodykę i wyniki ilościowych badań skażenie powierzchni mikroziarnami ściernymi oraz wpływ warunków obróbkowych na intensywność tego zjawiska. W badaniach wykorzystano mikroskopię skaningową i mikroanalizę rentgenowską.
Small city and a bridge. Landscape perspective
- Aleksandra Sas-Bojarska
2018
The aim of the paper is to present the problems connected with the location of big infrastructure objects; like bridges; in close neighbourhood to the small cities located in valuable environment and landscape; and the ways to minimize the potential threats. The case study of the small town Wyszogrod in central Poland will be presented to illustrate the values of the environment and landscape; which could have been easily destroyed by inadequate bridge project located in its surroundings. Complex environmental and landscape studies have been conducted within Environ-mental Impact Assessment (EIA). The results of the studies indicated that the environmental and landscape values could have been threatened; due to the technical parameters and the scale of the bridge and associated objects. The landscape impacts could be big scale; negative and non-reversible. During EIA a set of effective mitigation measures has been indicated. Due to them the project has been changed radically; what minimised environmental and landscape threats. The crucial conclusion is that Environmental Impact Assessment is a tool that can and should be used in controversial cases to predict potential negative changes and to avoid or lessen them. Described EIA was not only a formal procedure; but the process undertaken with the highest respect to environmental and landscape circumstances and visual quality of the space. The indirect; long-term; cumulative; permanent; irreversible and unavoidable landscape impacts have been described; as well as their spatial scope; scale; significance and the uncertainty of the prediction. This allowed to precise the adequate and effective mitigation measures to protect the unique character of the environment and landscape surrounding the city. The results of undertaken studies may serve as an excellent example in other cases; where new technical objects can destroy the relations between the city and its surroundings; especially regarding the landscape aspects.
Smart and resilient cities- new challanges for Polish cities in terms of 2020 energy efficiency and climate action
- Julia Kurek
2018
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. 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 Document-Centric Processing of Human Oriented Information Flows
- Magdalena Godlewska
2018 Pełny tekst COMPUTING AND INFORMATICS
Usually people prefer to focus on creative rather than repetitive and schematic work patterns. Still, they must spend a lot of time complying with the procedures, selecting the information they receive and repeatedly restoring the previous state of work. This paper proposes the Mobile INteractive Document architecture (MIND) - a document-centric uniform interface to provide both effective communication of content and coordination of activities performed on documents. MIND documents are proactive, capable of initiating process activities, interacting with individuals on their personal devices and migrating on their own between collaborators. Each MIND document is a mobile agent that has built-in migration policy to control its own workflow and services enabling proper processing of contained information. The architecture supports users in the implementation of procedures, and selection of services needed to work on the document. A Personal Document-Agent (PDA) is a further development of MIND aimed at preserving continuity of state of individuals' work to support their creativity and comfort of their daily work.