2018 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2018

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Modeling and MANOVA studies on toxicity and endocrine potential of packaging materials exposed to different extraction schemes
- Natalia Jatkowska
- Błażej Kudłak
- Stefan Tsakovski
- Galina Yotova
- Miroslava Nedyalkova
- Vasil Simeonov
- Anna Dołęga
- Jacek Namieśnik
2018 Pełny tekst ENVIRONMENTAL RESEARCH
The stability of the linings of packaging that is in contact with the goods stored has been of major concern during decades of the development of packaging materials. In this work, an attempt was undertaken to assess the applicability of using two bioassays (Microtox® and XenoScreen YES/YAS) in estimating the stability of packaging (cans, caps, multilayer material) and the impact of their degradation on the toxicity of some simulated media. The assessment of the impact of packaging storage conditions (temperature, disinfection, preservation, extracting and washing solvents) was planned and performed with i) regression modeling of the experimental effects on the ecotoxicity readings, ii) ANOVA and MANOVA estimation of the experimental conditions as significant factors affecting the toxicity results and iii) FTIR analysis of the packages. It is shown that the effects of temperature and extraction solvents could be quantitatively assessed by the agreement between all methods applied. It can be stated that temperature and acidity as well as the alcohol content in the sensitive media have the greatest impact on the toxicity of the extract and thus on the stability of the internal lining and the extractability of xenobiotics.
Modeling nitrous oxide production by a denitrifying-enhancedbiologically phosphorus removing (EBPR) activated sludge in thepresence of different carbon sources and electron acceptors
- Kamil Wiśniewski
- Maciej Kowalski
- Jacek Mąkinia
2018 WATER RESEARCH
In this study, the IWA Activated Sludge Model No. 2d (ASM2d) was expanded to identify the most important mechanisms leading to the anoxic nitrous oxide (N2O) production in the combined nitrogen (N) and phosphorus (P) removal activated sludge systems. The new model adopted a three-stage denitrification concept and was evaluated against the measured data from one/two-phase batch experiments carried out with activated sludge withdrawn from a local, large-scale biological nutrient removal wastewater treatment plant. The experiments were focused on investigating the effects of different external carbon sources (acetate, ethanol) and electron acceptors (nitrite, nitrate) on the mechanisms of N2O production in enhanced biological P removal by polyphosphate accumulating organisms (PAOs) and external carbon-based denitrification by ordinary heterotrophic organisms (OHOs). The experimental results explicitly showed that N2O production was predominantly governed by the presence of nitrite in the reactor regardless of the examined carbon source and the ratio COD/N in the reactor. The model was capable of accurately predicting (with R2 > 0.9) the behavior of not only N2O-N, but also NO3-N, NO2-N, soluble COD, and PO4-P. The simulation results revealed that only OHOs were responsible for N2O production, whereas the present denitrifying PAOs reduced only nitrate to nitrite.
Modeling of performance of a AUV vehicle towards limiting the hydro-acoustic field.
- Mirosław Gerigk
2018 Pełny tekst TransNav - The International Journal on Marine Navigation and Safety of Sea Transportation
Some results of research devoted to the modeling of a AUV-Stealth vehicle performance towards limiting its hydro-acoustic field are presented in the paper. At the beginning the AUV-Stealth autonomous underwater vehicle concept is described. Then the method of research is introduced. Next the key design drivers of the AUV-Stealth vehicle are presented. Between them are the AUV-Stealth hull form, arrangement of internal spaces, materials, hull covers, energy supply and propulsion system, etc. Some results of the hydrodynamic and stealth characteristics of the AUV-Stealth vehicle are briefly described. It is presented in the paper that the hull form, construction materials including the covers may affect the AUV-Stealth vehicle boundary layer and wake. This may create some problems of identification of the AUV-Stealth vehicle using a sonar or hydrophone. The final conclusions are presented.
Modeling of the Two-Dimensional Flow Caused by Sea Conditions and Wind Stresses on the Example of Dead Vistula
- Piotr Zima
2018 Pełny tekst Polish Maritime Research
The article presents the results of two-dimensional modeling of flows caused by the sea conditions and wind stresses on the example of Dead Vistula. Based on the available bathymetric data, a numerical model of the river section was created, which was supplemented with data on the position of the water table depending on hydrometeorological conditions. To describe the flow field in steady conditions, a simplified model of two-dimensional flow in the form of the bi-harmonic Helmholtz equation for the current function has been adopted, taking into account additional impacts caused by wind stresses on the water surface. Then the current function was converted into the velocity vector components. This equation, supplemented with appropriate boundary conditions, has been solved numerically using the finite difference method. On the basis of the available literature, 4 variants of hydrometeorological conditions were adopted, depending on the direction and strength of wind and sea conditions. The obtained results were compared with the results of published measurements taken on the studied section of the river. These calculations were the basis for the implementation of a two-dimensional model of the spread of pollutants in the studied section of the Dead Vistula.
Modelization of Nutrient Removal Processes at a Large WWTP Using a Modified ASM2d Model
- Jakub Drewnowski
- Jacek Mąkinia
- Lukasz Kopec
- Francisco-Jesus Fernandez-Morales
2018 Pełny tekst International Journal of Environmental Research and Public Health
The biodegradation of particulate substrates starts by a hydrolytic stage. Hydrolysis is a slow reaction and usually becomes the rate limiting step of the organic substrates biodegradation. The objective of this work was to evaluate a novel hydrolysis concept based on a modification of the activated sludge model (ASM2d) and to compare it with the original ASM2d model. The hydrolysis concept was developed in order to accurately predict the use of internal carbon sources in enhanced biological nutrient removal (BNR) processes at a full scale facility located in northern Poland. Both hydrolysis concepts were compared based on the accuracy of their predictions for the main processes taking place at a full-scale facility. From the comparison, it was observed that the modified ASM2d model presented similar predictions to those of the original ASM2d model on the behavior of chemical oxygen demand (COD), NH4-N, NO3-N, and PO4-P. However, the modified model proposed in this work yield better predictions of the oxygen uptake rate (OUR) (up to 5.6 and 5.7%) as well as in the phosphate release and uptake rates.
Modelling and simulation of GPU processing in the MERPSYS environment
- Tomasz Gajger
- Paweł Czarnul
2018 Pełny tekst Scalable Computing: Practice and Experience
In this work, we evaluate an analytical GPU performance model based on Little's law, that expresses the kernel execution time in terms of latency bound, throughput bound, and achieved occupancy. We then combine it with the results of several research papers, introduce equations for data transfer time estimation, and finally incorporate it into the MERPSYS framework, which is a general-purpose simulator for parallel and distributed systems. The resulting solution enables the user to express a CUDA application in a MERPSYS editor using an extended Java language and then conveniently evaluate its performance for various launch configurations using different hardware units. We also provide a systematic methodology for extracting kernel characteristics, that are used as input parameters of the model. The model was evaluated using kernels representing different traits and for a large variety of launch configurations. We found it to be very accurate for computation bound kernels and realistic workloads, whilst for memory throughput bound kernels and uncommon scenarios the results were still within acceptable limits. We have also proven its portability between two devices of the same hardware architecture but different processing power. Consequently, MERPSYS with the theoretical models embedded in it can be used for evaluation of application performance on various GPUs and used for performance prediction and e.g. purchase decision making.
Modelling Coarse Particulate Matter PM10 Concentration in the Tricity Area Using GIS
- Valentina Bresciani
- Chintankumar Padariya
- Marcin Kulawiak
2018
Environmental pollution is an issue of global concern, with Particulate Matter (PM) poisoning being a prime cause of lung cancer. This has led the European Commission to establish strict daily and annual PM concentration limits. The monitoring of air quality in major cities is the responsibility of European Member States. The Tricity, a 414.81 km 2 area in northern Poland, is monitored by a network of only 9 stations operated by the non-profit ARMAAG foundation. The stations provide hourly pollution and meteorological measurements in key areas of the Tricity, however the information regarding air quality in areas devoid of actual measurement stations must be obtained from other sources. The aim of the presented work is to relate the hourly PM10 concentrations in the Tricity area to other available data of various scale and resolution in order to provide a possibly accurate representation of air quality in the entire Tricity area.
Modelling of elastic wave propagation in a bolted joint using a thin layer of shell elements
- Rafał Kędra
- Magdalena Rucka
2018
There are many mathematical models describing the propagation of elastic waves through the imperfect boundary of two media. They were successfully applied to modelling of high frequency bulk waves and their interaction with local defects. On the other hand, the existing literature models of bolted connections ignore the aspect of imperfect connection between elements. Therefore, this paper presents the concept of application of a thin layer of shell finite elements to simulate disturbance propagation in a pretensioned bolted joint. The analyses were conducted in two stages. In the first stage, the contact analysis was made to determine the pressure distribution between the joined elements. Next, assuming linear relation between contact pressure and contact layer stiffness, dynamic explicit analysis was performed. The comparison between experimental and numerical results showed the possibility to apply this approach to more accurate modelling of elastic wave propagation.
Modelling of Objects Behaviour for Their Re-identification in Multi-camera Surveillance System Employing Particle Filters and Flow Graphs
- Karol Lisowski
- Andrzej Czyżewski
2018
An extension of the re-identification method of modeling objects behavior in muti-camera surveillance systems, related to adding a particle filter to the decision-making algorithm is covered by the paper. A variety of tracking methods related to a single FOV (Field of Vision) are known, proven to be quite different for inter-camera tracking, especially in case of non-overlapping FOVs. The re-identification methods refer to the determination of the probability of a particular object’s identity recognized by a pair of cameras. An evaluation of the proposed modification of the re-identification method is presented in the paper, which is concluded with an analysis of some comparison results brought by the methods implemented with and without a particle filter employment.
Modelling of performance of an AUV stealth vehicle. Design for operation.
- Mirosław Gerigk
2018
In the paper some results of research connected with modelling of performance and risk assessment of an AUV stealth vehicle are presented. A general approach to design of the stealth AUV autonomous underwater vehicle under consideration is introduced. The basic stealth characteristics of the AUV stealth vehicle are briefly described. The method of research is introduced. The AUV stealth vehicle concept is presented including the hull peculiarities. Between the results of research some basic stealth characteristics of the AUV stealth vehicle are presented. Some final remarks regarding the AUV stelath vehicle performance and its behaviour in the data operational conditions are given. The final conclusions are presented.
Modelling the loss of time caused by traffic incidents on motorways
- Krystian Birr
- Barbara Strzebrakowska
2018
For each road incident important factors like location, capacity reduction, traffic management, duration of road incidents and amount of traffic should be defined. All performer operations and effects of incidents affect the capacity of the road, average speed, time loss, vehicle queues and traffic jams. In the article road incidents were divided into planned and unexpected. Statistical analysis prepared using the database of traffic events which occurred on highways and expressways in Pomeranian Voivodeship is presented considering location of incidents on each road, frequency and duration of incidents and duration of rescue operation. Furthermore, the cases used to calibrate the model are characterised. Subsequently, the method of estimation of time loss resulting from incidents is presented. Within the methodology, mathematical and simulation models are distinguished. The tools for dynamic traffic modelling are also presented. In the last part of the article, the method of calculation value of time loss is presented. © 2018 The Authors, published by EDP Sciences.
Modelling the malware propagation in mobile computer devices
- María Signes-Pont
- Antonio Cortés-Castillo
- Higinio Mora-Mora
- Julian Szymański
2018 COMPUTERS & SECURITY
Nowadays malware is a major threat to the security of cyber activities. The rapid develop- ment of the Internet and the progressive implementation of the Internet of Things (IoT) increase the security needs of networks. This research presents a theoretical model of malware propagation for mobile computer devices. It is based on the susceptible-exposed- infected-recovered-susceptible (SEIRS) epidemic model. The scheme is based on a concrete connection pattern between nodes defined by both a particular neighbourhood which fixes the connection between devices, and a local rule which sets whether the link is infective or not. The results corroborate the ability of our model to perform the behaviour patterns provided by the ordinary differential equation (ODE) traditional method
Modelling Wetland Growing Season Rainfall Interception Losses Based on Maximum Canopy Storage Measurements
- Wojciech Ciężkowski
- Tomasz Edward Berezowski
- Małgorzata Kleniewska
- Sylwia Szporak-Wasilewska
- Jarosław Chormański
2018 Pełny tekst Water
This study estimates rainfall interception losses from natural wetland ecosystems based on maximum canopy storage measurements. Rainfall interception losses play an important role in water balance, which is crucial in wetlands, and has not yet been thoroughly studied in relation to this type of ecosystem. Maximum canopy storage was measured using the weight method. Based on these measurements, daily values of interception losses were estimated and then used to calculate long-term interception losses based on precipitation and potential evapotranspiration data for the 1971–2015 period. Depending mainly on the number of days with precipitation, the results show that total interception losses for the growing season as well as monthly interception losses are around 13% of gross rainfall. This value is similar to the values observed for some forests. Hence, interception losses should not be disregarded in hydrologic models of wetlands, especially because data trends in meteorological conditions (mainly number of days with precipitation) show that interception losses will increase in the future if those trends stay the same.
Modelowanie podziału zadań przewozowych w obszarach zurbanizowanych
- Krystian Birr
2018
Niniejsza rozprawa doktorska dotyczy problematyki modelowania podziału zadań przewozowych w procesie modelowania podróży. Wykonane analizy wykazały zasadność zastosowania dodatkowych czynników w modelowaniu wyboru środka transportu z uwagi na ich istotny wpływ na jakość modelu dla wybranych motywacji podróży. W pracy zawarto przykładowe modele uwzględniające każdy z analizowanych czynników. Z wykorzystaniem badań heurystycznych oraz wnioskowania rozmytego przeanalizowano możliwość uwzględnienia wpływu działań miękkich, wynikających z polityki transportowej w prognozowaniu podziału zadań przewozowych. Wykazano, że rozbudowa modeli stwarza możliwości wykonania prognoz uwzględniających zmiany w zakresie prognozowanych wartości dodatkowych zmiennych, opisujących uwarunkowania wpływające na wybór środka transportu. Ponadto uwzględnienie dodatkowych czynników w tym czynników jakościowych, związanych z działaniami miękkimi, pozwala na wykonanie analiz zróżnicowanych scenariuszy rozwoju analizowanego obszaru w zakresie polityki transportowej, stopnia rozwoju motoryzacji i innych elementów. W celu przedstawienia praktycznego zastosowania rozbudowanych modeli podziału zadań przewozowych, przedstawiono przykładowe wyniki analiz uwzględniających wybrane modele.
Modelowanie procesów biznesowych z wykorzystaniem narzędzi iGrafx Process 2015
- Marzena Grzesiak
2018
Książka przeznaczona jest dla studentów studiów ekonomicznych, w programie których znajdują się przedmioty związane z modelowaniem i symulacją procesów biznesowych, ale także dla analityków wykorzystujących narzędzia informatyczne do opisu i wizualizacji procesów. Poszczególne zagadnienia zostały zamknięte w 14 rozdziałach. W rozdziale 1 omówiono podstawowe zagadnienia definicyjne związane z podejściem procesowym oraz zarządzaniem procesami. Rozdział 2 został poświęcony kwestiom identyfikacji i klasyfikacji procesów oraz wdrażaniu podejścia procesowego. W rozdziale 3 poruszono tematykę modelowania procesów w organizacji oraz zaprezentowano potencjalne narzędzia informatyczne, jakie można w tym celu wykorzystać. Rozdziały 4-13 dotyczą budowy modelu przepływu procesu, definiowania jego parametrów, a następnie wnioskowania z danych umieszczonych w raporcie po przeprowadzeniu eksperymentu symulacyjnego. W tym celu wykorzystano narzędzia dostępne w programie iGrafx 2015. Rozdział 14 przedstawia realizację przykładowego zadania, począwszy od tworzenia diagramu przepływu procesu, a skończywszy na porównaniu wyników symulacji procesu dla dwóch scenariuszy.
Modelowanie procesu wrzenia i kondensacji w rozszerzonym zakresie ciśnień zredukowanych
- Blanka Jakubowska
2018
Niniejsza rozprawa doktorska ma na celu pokazanie wpływu uwzględnienia ciśnienia zredukowanego w analizowanym modelu opisują-cym współczynnik przejmowania ciepła na zbieżność z danymi eksperymentalnymi.Przedmiotem analizy jest półempiryczny model Mikielewicza w zastosowaniu do danych eksperymentalnych w kanałach konwencjonalnych i o małej średnicy płynów uznanych za perspektywiczne.W ramach realizowanych prac badawczych pozyskano i usystematyzowano bazę danych eksperymentalnych dla kanałów konwencjonalnych i o małej średnicy.Zebrana baza danych eksperymentalnych łącznie liczy około 3500 punktów eksperymentalnych dla CO2 oraz około 4150 punktów eksperymentalnych dla czynników:R600a, R290, R134a, R1234yf, amoniak, R152a, R245fa, R236fa oraz HFE7000.Przedstawiona w pracy analiza została przeprowadzona w oparciu o badania eksperymentalne dostępne w literaturze oraz w przypadku czynnika HFE7000 o własne badania eksperymentalne,które prowadzone były dla pełnego zakresu zmiany stopnia suchości oraz stosukowo szerokiego zakresu zmiany prędkości masowej. Następnie, opracowany został algorytm obliczeniowy w programie Excel, który umożliwia wyznaczenie współczynników regresji wielu zmiennych celem dopasowania bazy danych do postaci ogólnej korelacji na współczynniki przejmowania ciepła w przepływie dwufazowym dla różnych płynów perspektywicznych. Rozwijany od lat w KEiAP PG model wrzenia i kondensacji w przepływie do modelowania wymiany ciepła wykorzystuje wyrażenie opisujące opory przepływu dwufazowego.W przedstawionych w pracy obliczeniach wykorzystano do tego celu dziewięć modeli:Müllera–Steinhagen i Hecka, zmodyfikowaną zależność Müllera-Steinhagena i Hecka, Zhanga i Webba, Cioncoliniego i innych, Sempértegui-Tapii i Ribatskiego, Trana, Friedela, uwzględniającą wpływ efektów związanych z przyłożonym strumieniem ciepła oraz nową postać uwzględniającą wpływ ciśnienia zredukowanego. W kolejnym etapie, uwzględniono w algorytmie obliczeniowym wpływ efektów związanych z ciśnieniem zredukowanym. Ponadto, w pracy przedstawiono również algorytm doboru wartości wykładnika potęgowego dla nowego członu wprowadzonego do półemirycznej korelacji oraz przeprowadzono obliczenia w oparciu o zweryfikowany model i porównano uzyskane wyniki z posiadaną bazą danych, co ostatecznie pozwoliło na zaproponowanie nowej postaci korelacji pozwalającej na wyznaczenie współczynników przejmowania ciepła w przepływie dwufazowym, która w swoim opisie uwzględnia wpływ ciśnienia zredukowanego.
Modelowanie przepływu wody i powietrza w ośrodkach porowatych o zmiennym nasyceniu za pomocą równania Richardsa i modelu dwufazowego
- Witold Tisler
2018 Pełny tekst
W pracy zostały przedstawione symulacje numeryczne przepływu w gruntach nasyconych i nienasyconych bazujące na dwóch najbardziej rozpowszechnionych modelach matematycznych: równaniu Richardsa, gdzie przepływ powietrza jest pomijany i rozważa się tylko przepływ wody oraz modelu dwufazowym, w którym pod uwagę bierze się oba płyny. Rozwiązanie Richardsa jest bardziej uproszczone oraz zdecydowanie częściej stosowane w najpopularniejszych programach inżynierskich. Ponadto w pracy wykonano przegląd oraz zaproponowano klasyfikację problemów, w których przepływ fazy gazowej ma istotny wpływ na procesy zachodzące w ośrodku gruntowym.
Modern Material Solutions Applied in Pediatric Facilities
- Agnieszka Gębczyńska-Janowicz
- Bogusława Konarzewska
2018 Pełny tekst Architecture Civil Engineering Environment
New tendencies in forming of the health services functional buildings’ systems shaped along with the emergence of caring for patient’s mental condition in medical sciences. The interior design harmonized with the medical function became an incredibly important feature. This opened up new opportunities for the architecture of health care facilities. A positive architecture’s impact on the user’s well-being is remarkably important in the case of medical care units for youngest patients. For children contacts with clinics and hospitals implies the stress of separation from family and home environment as well as the fear of medical procedures that cause pain. Properly shaped space allows for the reduction of negative experiences linked with staying in a medical institution. It is worth looking at the contemporary material solutions that allow for the fulfillment of the required sanitary and hygienic standards, enabling at the same time to realize bold visions of pediatric medical facilities’ designers.
Modification of quaternary structure of Candida albicans GlcN-6-P synthase and its desensitization to inhibition by UDP-GlcNAc by site-directed mutagenesis
- Karolina Kwiatkowska-Semrau
- Marek Wojciechowski
- Iwona Gabriel
- Sara Crucho
- Sławomir Milewski
2018 BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS
Site-directed mutagenesis of the CaGFA1 gene encoding glucosamine-6-phosphate synthase from Candida albicans was performed. Desensitization of the enzyme to inhibition by UDPGlcNAc was achieved upon T487I and H492F substitutions at the UDP-GlcNAc binding site, exchange of D524, S525 and S527 for Ala at the dimer:dimer interface and construction of the tail-lock array (L434R and L460A) at the C-tail region. The first two sets if mutageneses but not the last one resulted in conversion of the tetrameric enzyme into its dimeric form. Evidence for links and communication between the UDP-GlcNAc binding site and the imer-dimer contact areas are presented. The CaGfa1-T487IH492F and CaGfa1-KHSH-D524AS525AS527A muteins are the first examples of the successful conversion of eukaryotic GlcN-6-P synthase into its prokaryotic-like version upon rational sitedirected mutagenesis.
Modifications of total synthesis of mycophenolic acid
- Grzegorz Cholewiński
- Magdalena Małachowska - Ugarte
- Agnieszka Siebert
- Michał Prejs
- Krystyna Dzierzbicka
2018 Pełny tekst Current Chemistry Letters
The total synthesis of mycophenolic acid (MPA), a potent immunosuppressant, was modified. The obtained mycophenolic acid was suitable for further preparation of new prospective immunosuppressants with improved therapeutic properties.