2019 - Repozytorium publikacji - Politechnika Gdańska

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DIAGNOSIS OF MALIGNANT MELANOMA BY NEURAL NETWORK ENSEMBLE-BASED SYSTEM UTILISING HAND-CRAFTED SKIN LESION FEATURES
- Michał Grochowski
- Agnieszka Mikołajczyk
- Arkadiusz Kwasigroch
2019 Pełny tekst Metrology and Measurement Systems
Malignant melanomas are the most deadly type of skin cancer but detected early have high chances for successful treatment. In the last twenty years, the interest of automated melanoma recognition detection and classification dynamically increased partially because of public datasets appearing with dermatoscopic images of skin lesions. Automated computer-aided skin cancer detection in dermatoscopic images is a very challenging task due to uneven datasets sizes, the huge intra-class variation with small interclass variation, and the existence of many artifacts in the image. One of the most recognized methods of melanoma diagnosis is the ABCD method. In the paper, we propose an extended version of this method and an intelligent decision support system based on neural networks that uses its results in a form of hand-crafted features. Automatic determination of the skin features used by the ABCD method is difficult due to the large diversity of images of various quality, the existence of hair, different markers and other obstacles. Therefore, it was necessary to apply advanced methods of preprocessing the images. The system is an ensemble of ten neural networks, working in parallel and one network using their results to generate a final decision. This system structure allowed us to increase the efficiency of the operation by several percentage points compared to a single neural network. The proposed system is trained on over 5000 and tested afterward on 200 skin moles. The presented system can be used as a decision support system for primary care physicians, as a system capable of self-examination of the skin with a dermatoscope and also as an important tool to improve biopsy decision making.
Diagnostic Model of Crankshaft Seals
- Piotr Bzura
2019 Pełny tekst Polish Maritime Research
T he paper presents a research stand being a diagnostic model of radial lip seals used, among others, on crankshafts of piston combustion engines in order to identify the correctness of their operation. The possibility of determining the technical condition of lip seals on the basis of the proposed coefficient of correctness of operation has been described. T he basic features of seals influencing their correctness of operation were also described, along with examples of determining the durability limits of lip seals. A modified version of the friction node of the T-02 four-ball apparatus is presented. It allows to check the correctness of sealing lips operation as well as to test the compatibility between the steel shaft, sealing lip and sealed lubricating oil. It was shown that the test results con-firmed the usefulness of the hypothesis that the quality of oil affects the durability of sealing lips and their coefficient of correctness. Additionally, attention was paid to the possibility of analyzing the pumping effect affecting the transition of the seal-shaft system from the state of partial suitability S2 to the state of full suitability S1 or to the state of unfitness S3, and because the change in the state of such a system is random, it requires a probabilistic analysis.
Diagnostics and monitoring of the longest span extradosed bridge in Europe
- Mikołaj Miśkiewicz
- Krzysztof Wilde
2019
The article presents complex diagnostic procedures applied for the purpose of behavior analysis of the extradosed bridge with the longest span in Europe that was built in 2018 in Poland. The system of health monitoring was used to: register internal forces in temporary supports, monitor concrete bonding, perform in situ diagnostics and operation tests. The bridge is a continuous four-span structure with spans theoretical lengths equaling: 132.5+206.0+206.0+132.5 m. During the construction of the bridge, two technical monitoring systems were used. As a consequence of their application, it was possible to carry out works with the lowest level of risk and therefore the work schedule was accelerated. The first of systems was designed to measure forces transferred to temporary supports during cantilever construction stages. The second system was designed to measure changes of the strength of curing concrete, after it was poured at the site, which allowed to speed up the removal of the scaffoldings and post-tension of cross section with cables. When the bridge was finished, a Structural Health Monitoring (SHM) system was installed and final acceptance tests were launched. The obtained results were used to validate theoretical assumptions done at the stage of the bridge structural design and provided insight into the complex bridge behavior.
Diagnostics of pillars in St. Mary’s Church (Gdańsk, Poland) using the GPR method
- Jacek Lachowicz
- Magdalena Rucka
2019 Pełny tekst International Journal of Architectural Heritage
The main goal of this study was non-destructive evaluation of pillars in the St. Mary’s Church (Gdańsk, Poland) using the ground penetrating radar (GPR) technique. The GPR inspection was conducted on four brick masonry pillars and five pillars strengthened by reinforced concrete jacketing. Data were acquired with a 2 GHz antenna along longitudinal and transverse profiles. The study involved the estimation of the electromagnetic wave velocity in both brick and concrete, the inspection of the internal structure of the pillars and the precise identification of reinforcement bars. To determine the wave velocity in bricks, a novel mathematical model was developed. Finite-difference time-domain (FDTD) simulations were used to verify and assess the feasibility of the proposed model. Finally, GPR maps were processed using the hyperbolic summation method to visualize the reinforcement distribution in the concrete jacket.
Diagonalized Macromodels in Finite Element Method for Fast Electromagnetic Analysis of Waveguide Components
- Krzysztof Nyka
2019 Pełny tekst Electronics
A new technique of local model-order reduction (MOR) in 3-D finite element method (FEM) for frequency-domain electromagnetic analysis of waveguide components is proposed in this paper. It resolves the problem of increasing solution time of the reduced-order system assembled from macromodels created in the subdomains, into which an analyzed structure is partitioned. This problem becomes particularly relevant for growing size and count of the macromodels, and when they are cloned in multiple locations of the structures or are used repeatedly in a tuning and optimization process. To significantly reduce the solution time, the diagonalized macromodels are created by means of the simultaneous diagonalization and subsequently assembled in the global system. For the resulting partially diagonal matrix, an efficient dedicated solver based on the Schur complement technique is proposed. The employed MOR method preserves frequency independence of the macromodels, which is essential for efficient diagonalization, as it can be performed once for the whole analysis bandwidth. The numerical validation of the proposed procedures with respect to accuracy and speed was carried out for varying size and count of macromodels. An exemplary finite periodical waveguide structure was chosen to investigate the influence of macromodel cloning on the resultant efficiency. The results show that the use of the diagonalized macromodels provided a significant solution speedup without any loss of accuracy
Diaminophosphinoboranes: effective reagents for phosphinoboration of CO2
- Natalia Szynkiewicz
- Anna Ordyszewska
- Jarosław Chojnacki
- Rafał Grubba
2019 Pełny tekst RSC Advances
The monomeric diaminophosphinoboranes readily react with CO2 under mild conditions to cleanly form products of the general formula R2P-C(=O)-O-B(NR2)2 in the absence of a catalyst. The isolated products from the CO2-phosphinoboration were fully characterized by NMR spectroscopy, IR spectroscopy, and X-ray diffraction. The mechanism of CO2 phosphinoboration with diaminophosphinoboranes was elucidated by DFT calculations.
Die Sandgrube „Köplitz“ – ein interessanter geologischer Aufschluss am Nordwestrand der Schmiedeberger Stauchendmoräne
- Roland Wimmer
- Ewa Wagner-Wysiecka
2019 Pełny tekst Mauritiana
Die Kiessandgrube Köplitz ermöglicht einen Einblick in die komplizierten, durch glazidynamische Überprägung gekennzeichneten geologischen Lagerungsverhältnisse im Bereich der Schmiedeberger Stauchendmoräne. Anhand neuer Geländedokumentationen wird ein kleiner Eindruck vom komplizierten injektiven „Fließfalten-Schuppenbau“ der Stauchendmoräne vermittelt. Die steil aufgerichteten, aus tertiären (Untermiozän bis Oligozän) und quartären (elster- bis saalekaltzeitlichen) Sedimenten bestehenden Schollenpakete streichen nahezu an der Geländeoberfläche aus. In den tertiären Ablagerungen wurden in den letzten Jahren wiederholt Einzelfunde von Bernstein gemacht. Sie wurden mittels der Infrarotspektroskopie untersucht.
Dietary antioxidants as a source of hydrogen peroxide
- Michalina Grzesik
- Grzegorz Bartosz
- Ireneusz Stefaniuk
- Monika Pichla
- Jacek Namieśnik
- Izabela Sadowska-Bartosz
2019 FOOD CHEMISTRY
Studies of 54 antioxidants revealed that 27 of them, mainly polyphenols, generated hydrogen peroxide (H2O2) when added to Dulbecco’s modified Eagle’s medium (DMEM), other media used for culture of mammalian and yeast cells and phosphate-buffered saline. The most active antioxidants were: propyl gallate (PG), (−)-epigallocatechin gallate (EGCG) and quercetin (Q). Chelex treatment and iron chelators decreased H2O2 generation suggesting that transition metal ions catalyze antioxidant autoxidation and H2O2 production. Green tea also generated H2O2; tea prepared on tap water generated significantly more H2O2 than tea prepared on deionized water. Ascorbic acid decreased H2O2 production although it generated H2O2 itself, in the absence of other additives. Lemon added to the tea significantly reduced generation of H2O2. Hydrogen peroxide generated in the medium contributed to the cytotoxicity of PG, EGCG and Q to human prostate carcinoma DU-145 cells, since catalase increased the survival of the cells subjected to these compounds in vitro.
Diethyl carbonate as a green extraction solvent for chlorophenol determination with dispersive liquid–liquid microextraction
- Marek Tobiszewski
- Weronika Zabrocka
- Marta Bystrzanowska
2019 Pełny tekst Analytical Methods
The principles of green analytical chemistry indicate that the search for greener organic solvents for extraction applications is crucial. In this study diethyl carbonate (DEC) is proved to be a green solvent, as it is relatively nontoxic, obtainable from renewable resources and biodegradable. Here it is applied as an extraction solvent for chlorophenol determination in water samples with dispersive liquid–liquid microextraction. The multiobjective optimization for 7 chlorophenols is done with the design of an experiment combined with Derringer's desirability function. The optimized parameters in the extraction step are 300 mL of DEC, 0.5 mL of methanol, 8 mL of water sample and 7.5% of inorganic salt addition. The values of LOQ are from 0.01 to 0.3 mg L1, and CVs are between 7.1 and 17.3% for 7 CPs. In this study DEC is proved to be a promising, green solvent, applicable in analytical extractions.
Differences between selected volatile aromatic compound concentrations in sludge samples in various steps of wastewater treatment plant operations
- Hubert Byliński
- Justyna Aszyk
- Paweł Kubica
- Małgorzata Szopińska
- Sylwia Fudala-Książek
- Jacek Namieśnik
2019 JOURNAL OF ENVIRONMENTAL MANAGEMENT
Sewage sludge, one of the main wastes generated during wastewater treatment, constitutes an important source of emissions of volatile chemical compounds such as volatile aromatic compounds These substances may undergo various changes as a result of operations and unit processes, which affects their concentrations in sewage sludge. An important factor determining the potential hazardousness of volatile organic compounds is the quality of wastewater delivered to wastewater treatment plants and the technical and equipment solutions applied to wastewater. In this study, a rapid and sensitive headspace gas chromatography method, coupled with tandem mass spectrometry using the standard addition method, was developed for the determination of selected volatile aromatic compounds in sewage sludge samples collected at different stages from three wastewater treatment plants located in Poland. This study attempted to assess the relationship between differences in the emissions of representative VACs and the given stage of the technological process within three analysed wastewater treatment plants. The highest concentration levels were determined for p-cresol, with concentrations ranging from 44.0*101±5.6*101 ng/g of sludge (sludge from aerobic chamber, wastewater treatment plant no.2) to 47.7*102±6.9*102 ng/g of sludge (sludge from aerobic chamber, wastewater treatment plant no.1), while the lowest concentration levels were observed for chlorobenzene, with concentrations ranging from 0.1300 ± 0.0030 ng/g of sludge (sludge from anaerobic chamber, wastewater treatment plant no.2), to 0.2606 ± 0.0046 ng/g of sludge (primary sludge, wastewater treatment plant no.1). The repeatability of the method was better than 10%, with accuracy levels in the ranges 89%–108%.Wastewater treatment technologies and residual sludge management in the selected wastewater treatment plantsinfluenced volatile aromatic compounds emission. Furthermore, the diversity of the wastewater quality, depending on the catchment area, is also an important factor determining the differentiation in volatile aromatic compounds emission. The microbial composition of raw wastewater highly influenced not only the treatment effectiveness of wastewater treatment plants but also the production of intermediate products, such as volatile aromatic compounds, which may contribute to odour emissions.
Digital Government as Implementation Means for Sustainable Development Goals
- Ignacio Marcovecchio
- Mamello Thinyane
- Elsa Estevez
- Tomasz Janowski
2019 Pełny tekst International Journal of Public Administration in the Digital Age
One of the challenges for implementing Sustainable Development Goals (SDGs) is the measurement of indicators that represent progress towards such goals. Measuring such progress enables data-driven decision-making and management of SDG-relevant projects and strategies. The premise of this research is that measuring such indicators depends on measuring so-called means of implementation, i.e. activities that directly contribute to the achievement of SDGs. Building on this premise, this article studies how the measurement of digital government (DG) can contribute to the measurement of SDGs. In particular, how the indicators originating in three DG measurement instruments can inform the SDG indicators. The main finding is an alignment matrix, showing how the DG indicators contribute with varying level of specificity to the measurement of 10 SDG indicators.
Dimethyl ether (DME) as potential environmental friendly fuel
- Patrycja Makoś
- Edyta Słupek
- Joanna Sobczak
- Dawid Zabrocki
- Jan Hupka
- Andrzej Rogala
2019 Pełny tekst E3S Web of Conferences
In recent years, there has been a growing interest in replacing petroleum fuels with so-called second generation environmental friendly fuels. Compared to traditional petroleum fuels dimethyl ether (DME) could be used as a clean high-efficiency compression ignition fuel with reduced particulate matter (PM), sulfur oxides (SOx), hydrocarbons (HC), carbon monoxide (CO) as well as combustion noise. Compared to some of the other leading alternative fuel candidates i.e., methane, methanol, ethanol, compressed natural gas, DME appears to have the largest potential impact on society including well-to-wheel greenhouse gas emissions, non-petroleum feedstocks, well-to-wheel efficiencies, fuel versatility, infrastructure, availability, economics, and safety and should be considered as the fuel of choice for eliminating the dependency on petroleum. This paper reviews the properties and the DME combustion effects on environmental and they were compared to diesel characteristic as well as the effect of blending DME with liquefied petroleum gas (LPG), conventional diesel fuel and biodiesel were discussed.
Diphosphination of CO2 and CS2 mediated by frustrated Lewis pairs - catalytic route to phosphanyl derivatives of formic and dithioformic acid
- Natalia Szynkiewicz
- Łukasz Ponikiewski
- Rafał Grubba
2019 Pełny tekst CHEMICAL COMMUNICATIONS
The first example of CO2 diphosphination is described. Reactions of unsymmetrical diphosphanes with CE2 (E = O, S) catalyzed by BPh3 insert a CE2 molecule into the P-P bond with formation of the products of the general formula R2P-E-C(=E)-PR2. The obtained CO2 adducts arise from synergistic interaction of diphosphane and borane with CO2 molecule.
Dirac fermions and possible weak antilocalization in LaCuSb2
- Juan Chamorro
- A. Topp
- Y. Fang
- Michał Winiarski
- C. R. Ast
- M. Krivenkov
- A. Varykhalov
- B. J. Ramshaw
- Leslie Schoop
- Tyrel McQueen
2019 Pełny tekst APL Materials
Layered heavy-metal square-lattice compounds have recently emerged as potential Dirac fermion materials due to bonding within those sublattices. We report quantum transport and spectroscopic data on the layered Sb square-lattice material LaCuSb2. Linearly dispersing band crossings, necessary to generate Dirac fermions, are experimentally observed in the electronic band structure observed using angle-resolved photoemission spectroscopy, along with a quasi-two-dimensional Fermi surface. Weak antilocalization that arises from two-dimensional transport is observed in the magnetoresistance, as well as regions of linear dependence, both of which are indicative of topologically nontrivial effects. Measurements of the Shubnikov–de Haas quantum oscillations show low effective mass electrons on the order of 0.065me, further confirming the presence of Dirac fermions in this material.
Discovering Rule-Based Learning Systems for the Purpose of Music Analysis
- Grazina Korvel
- Bożena Kostek
2019 Pełny tekst Journal of the Acoustical Society of America
Music analysis and processing aims at understanding information retrieved from music (Music Information Retrieval). For the purpose of music data mining, machine learning (ML) methods or statistical approach are employed. Their primary task is recognition of musical instrument sounds, music genre or emotion contained in music, identification of audio, assessment of audio content, etc. In terms of computational approach, music databases contain imprecise, vague and indiscernible data objects. Moreover, most of the machine learning algorithms outcomes are given as a black-box result. Also, underfitting or overfitting may occur, meaning that either the model description is not complex enough or the test set is too small or not sufficiently representative. Thus the goal is to generalize the model. To overcome some of these problems, rule-based systems may be used, e.g., based on rough set theory that shows the outcome in the form of rules interconnecting features retrieved from music. Thus, first, principles of rule-based classifiers and particularly rough sets (RS) are presented, showing their usability in the music domain. A potential of the rough set-based approach was shown in the context of music genre recognition. The results were analyzed in terms of the recognition rate and computation time efficiency.
Discovery of Stylistic Patterns in Business Process Textual Descriptions: IT Ticket Case
- Nina Rizun
- Aleksandra Revina
- Vera Maister
2019 Pełny tekst
Growing IT complexity and related problems, which are reflected in IT tickets,create a need for new qualitative approaches. The goal isto automate the extraction of main topics described in tickets in order to provide high quality support for the IT process workers and enablea smooth service delivery to the end user. Present paper proposes a method of knowledge extraction in a form of stylistic patterns in business process (BP) texts, here in incoming IT tickets texts. Hereby, the authors set an objective to predicttheir readability andperceivedcomplexityfor a process worker, what will influencefurther tasks execution. The results of experimental analysis of a data set of incoming ticket texts from anITIL-based Change Management process showed that the specificity of stylistic patterns expressing the readability of a ticket and perceived complexity could be identified with the help of proposed measures of the ticket length, parts-of-speech distributions and wording style (PDF) Discovery of Stylistic Patterns in Business Process Textual Descriptions: IT Ticket Case. Available from: https://www.researchgate.net/publication/331843977_Discovery_of_Stylistic_Patterns_in_Business_Process_Textual_Descriptions_IT_Ticket_Case [accessed Jun 23 2019].
Discussion on “Coupled effective stress analysis of insertion problems in geotechnics with the Particle Finite Element Method” by L. Monforte, M. Arroyo, J.M. Carbonell, and A. Gens
- Jakub Konkol
- Lech Bałachowski
2019 Pełny tekst COMPUTERS AND GEOTECHNICS
Addressed here is the Particle Finite Element Method (PFEM) modelling of undrained CPTu penetration with regard to a reference analytical solution based on the Spherical Cavity Expansion Method (SCEM). Also discussed is the choice of the soil model and its parameters. The effect of cone interface friction on CPTu simulation is analyzed in a series of penetration tests using Arbitrary Lagrangian-Eulerian (ALE) and Updated Lagrangian (UL) methods. The results of the simulations are compared with the Authors’ proposal.
Dispersive liquid-liquid microextraction combined with gas chromatography–mass spectrometry for in situ determination of biogenic amines in meat: Estimation of meat's freshness
- Wojciech Wojnowski
- Justyna Płotka-Wasylka
- Jacek Namieśnik
2019 Pełny tekst MICROCHEMICAL JOURNAL
A dispersive liquid-liquid microextraction (DLLME) gas chromatography–mass spectrometry (GC–MS) technique was developed for the determination of selected biogenic amines (BAs) in samples of poultry, pork and beef. Prior to the extraction process, an appropriate volume of sodium hydroxide solution was added to each of the portioned samples. Next, samples were homogenized, centrifuged and finally sonicated at an increased temperature. After another centrifugation, the supernatant was made up to 50 mL in a calibrated flask. Subsequently, 5 mL of supernatant was separately subjected to a derivatization and extraction procedure. A mixture of methanol (dispersive solvent; 210 μL), chloroform (extractive solvent; 300 μL), and isobutyl chloroformate (derivatizing reagent; 100 μL) was used in the extraction process together with an admixture of pyridine and HCl in order to eliminate the by-products. The application of the method enables fast derivatization and extraction of the BAs and a straightforward and rapid sample enrichment. It displayed good linearity, intra- and inter-day precision and good recoveries. The proposed methodology is characterized by low limits of detection and quantification (0.003–0.009 μg/g and 0.009–0.029 μg/g, respectively). The green character of the method was established based on the results of two tools, namely the Analytical Eco-Scale and GAPI. It was successfully used to analyse samples of poultry, porcine and bovine meat. Multivariate statistical data analysis was applied in order to evaluate the potential use of the determined BAs as spoilage markers of particular meat types.
Dissociative ionization dynamics of dielectric gas C3F7CN
- Milos Ranković
- J Chalabala
- Mateusz Zawadzki
- Jaroslav Kočišek
- Petr Slavíček
- Juraj Fedor
2019 PHYSICAL CHEMISTRY CHEMICAL PHYSICS
Fluoronitrile C3F7CN is a promising candidate for the replacement of SF6 dielectric gas in high-voltage insulation. We present a combined experimental and theoretical study on its ionization dynamics probed in the 0-100 eV energy range. We exploited the total ion collection technique to determine the absolute ionization cross section, mass spectrometry to determine the fragment branching ratios and ab initio nonadiabatic molecular dynamics to simulate the ionization process. The latter two approaches showed the dominating presence of the CF+3 cation over the whole electron energy range. The Binary-Encounter-Bethe (BEB) approximation reproduces experimental cross sections very well and reveals that the ionization from a surprisingly large number of orbitals contributes almost equally to the processes. We show that the initially populated cation excited states undergo an ultrafast internal conversion to the ground state where the dissociation into a single decay channel takes place. Implications for the use of C3F7CN as an insulating material are discussed.
Distortional buckling of composite thin-walled columns of a box-type cross section with diaphragms
- Czesław Szymczak
- Marcin Kujawa
2019 Pełny tekst ACTA MECHANICA
Distortional buckling of axially compressed columns of box-like composite cross sections with andwithout internal diaphragms is investigated in the framework of one-dimensional theory. The channel membersare composed of unidirectional fibre-reinforced laminate. Two approaches to the member orthotropic materialare applied: homogenization based on the theory of mixture and periodicity cells, and homogenization basedon the Voigt–Reuss hypothesis. The principle of stationary total potential energy is applied to derive thegoverning differential equation. The obtained buckling stress is valid in the linear elastic range of columnmaterial behaviour. Numerical examples address simply supported columns, and analytical critical stressformulas are derived. The analytical and FEM solutions are compared, and sufficient accuracy of the resultsis observed.